title: Tejashwi Yadav

text: Tejashwi Yadav was born in Gopalganj, Bihar on 9 November 1989 to Rabri Devi and Lalu Prasad Yadav, both of whom were members of the Bihar Legislative Assembly and later became the Chief Ministers of Bihar. He is one of 9 siblings (7 sisters and 2 brothers) among whom he is the youngest. He began his schooling in Patna and later moved to Delhi, accompanying his eldest sister Misa Bharti who was enrolled for an MBBS. In Delhi, Yadav initially attended Delhi Public School in Vasant Vihar for primary classes till Class V.


title: Tejashwi Yadav

text: His 7 sisters are Misa Bharti, Rohini, Chanda, Ragini, Hema, Anushka and Raj Lakshmi Yadav. Tej Pratap Yadav is his elder brother.


title: Tejashwi Yadav

text: Anushka Yadav is married to Chiranjeev Rao, while Raj Lakshmi Yadav is married to Tej Pratap Singh Yadav.


title: Tejashwi Yadav

text: According to his school teachers, he was a scrawny and shy child. He was also the school cricket team's captain. From Class VI onwards, he began attending Delhi Public School, R. K. Puram. The principal of the school described him as an introvert and a cricket enthusiast. He played in the school's cricket team and was selected for the U-15 cricket team of Delhi as an all rounder at the age of 13. According to his teammates, he had helped them win a number of tournaments during his first season, his team also included Virat Kohli as its captain. The U-15 team won the national championship where Yadav had a match winning partnership with Ishant Sharma in the finals. He dropped out of his school in Class X to pursue a sports career, and was eventually got into U-17 and U-19 cricket team of Delhi. Tejashwi was also selected in the list of standby players for the world cup winning U-19 Indian national cricket team, later in the same year.


title: Tejashwi Yadav

text: Yadav was contracted by the Delhi Daredevils for the 2008 Indian Premier League franchise. He remained in the reserve bench of the team in the entire seasons between 2008 and 2012.


title: Tejashwi Yadav

text: He was also selected for the state level Jharkhand cricket team in 2009. His professional cricket debut began with 4 Twenty20 matches primarily in the capacity of a bowler in the Syed Mushtaq Ali Trophy. Following which he was called for a first class game against Vidarbha cricket team at Dhanbad. He was fielded as the number 7 batsman and bowled in 5 overs. In 2010, he made his one-day debut in the Vijay Hazare Trophy and played two matches against Odisha cricket team and the Tripura cricket team respectively; his team lost the first match and won the second one, Yadav took a wicket against Tripura.


title: Tejashwi Yadav

text: By 2013, Yadav had retired from his cricket career. According to a 2013 article of the "Business Standard", "the stupefying talent soon gave way to a spate of middling performances, ensuring that his cricketing career never fully took off." According to his team coaches, he had the potential for success in his cricket career but was let down by the lack of adequate facilities for sportsmen in Bihar; the state also lacked a domestic cricket team which had caused Yadav to move to another state like most other Bihari players where local players were prioritised for playing matches.


title: Tejashwi Yadav

text: Since 2010, while still pursuing his cricket career, Yadav had begun campaigning for the Rashtriya Janata Dal. Following his advent into politics, he was credited for successfully modernising campaigning strategies and initiating digital outreach for the party. According to Rashtriya Janata Dal insiders, Yadav had also convinced Lalu Prasad to form a coalition with Nitish Kumar and his Janata Dal (United) following the poor performance of both the parties in the 2014 Indian general election in Bihar. Eventually an alliance was formed between the Janata Dal (United), Rashtriya Janata Dal and the Indian National Congress.


title: Tejashwi Yadav

text: In the 2015 Bihar Legislative Assembly election, Yadav stood as the candidate of the "Mahagathbandan" (Grand Alliance) from both the Raghopur was elected as the representative of the constituency. The election also resulted in an overwhelming majority for the alliance in the assembly, which led to Yadav being appointed as the Deputy Chief Minister of Bihar and received the portfolios of public works, forestry and environment in the 5th Nitish Kumar cabinet.


title: Tejashwi Yadav

text: In 2017, the Central Bureau of Investigation (CBI) filed a case and the Enforcement Directorate (ED) launched a probe in relation to money laundering in a 2004 corruption case involving the Indian Railway Catering and Tourism Corporation, against Yadav and other members of his family including his parents Rabri Devi and Lalu Prasad Yadav. This caused Nitish Kumar to pull the Janata Dal (United), out of the alliance and form a new government along with the Bharatiya Janata Party. Subsequently, Yadav became the leader of opposition owing to the Rashtriya Janata Dal being the largest party in the state legislature. In response to the case lodged against him, Yadav accused the Bharatiya Janata Party of abusing government machinery to carry out political schemes. In 2018, he was granted relief in the case by the Delhi High Court after he maintaining that he could not have played a role as the allegation was leveled on him at a time when he was only 14 years old.


title: Tejashwi Yadav

text: By March 2018, Yadav had become the de facto leader of the Rashtriya Janata Dal. Upon appointment, he issued an official apology addressing the people of Bihar for "lapses and mistakes" that may have been committed by the party during its tenure in the state government and that he himself was unaware of them being too young at the time. During his term as the leader of opposition, Yadav later became involved in organising food relief in the aftermath of the 2019 Bihar floods.


title: Tejashwi Yadav

text: Yadav led the Rashtriya Janata Dal in the 2020 Bihar Legislative Assembly elections, as the Chief Ministerial candidate of the Mahagathbandhan. The alliance won 110 seats in total out of 243, with RJD winning 75 seats, continuing to remain the single largest political party in Bihar. Since the majority required was 122, the alliance was unable to form the government, and Yadav was elected as the Leader of Opposition of Bihar.


title: Tejashwi Yadav

text: On 10 August 2022, he took oath as the Deputy Chief Minister of Bihar with Nitish Kumar taking oath as Chief Minister as part of the Mahagathbandan formed with RJD, Congress and other Opposition Parties.


title: Tejashwi Yadav

text: In 2008, Yadav became the subject of new reports following an altercation where he and his brother Tej Pratap Yadav were allegedly assaulted at a traffic stop by a group in a neighbouring car and were hospitalised for bruises as a result; in the aftermath the Railway Protection Force (RPF) personnel accompanying the two lodged a complaint to register the loss of weaponry. The group alleged that the two had harassed some girls while according to the RPF personnel, the group including both boys and girls had abused and assaulted the brothers and one of the RPF constables which led to the loss of his service revolver.


title: ZFS

text: ZFS (previously: Zettabyte File System) is a file system with volume management capabilities. It began as part of the Sun Microsystems Solaris operating system in 2001. Large parts of Solaris – including ZFS – were published under an open source license as OpenSolaris for around 5 years from 2005, before being placed under a closed source license when Oracle Corporation acquired Sun in 2009/2010. During 2005 to 2010, the open source version of ZFS was ported to Linux, Mac OS X (continued as MacZFS) and FreeBSD. In 2010, the illumos project forked a recent version of OpenSolaris, to continue its development as an open source project, including ZFS. In 2013, OpenZFS was founded to coordinate the development of open source ZFS. OpenZFS maintains and manages the core ZFS code, while organizations using ZFS maintain the specific code and validation processes required for ZFS to integrate within their systems. OpenZFS is widely used in Unix-like systems.


title: ZFS

text: The management of stored data generally involves two aspects: the physical volume management of one or more block storage devices such as hard drives and SD cards and their organization into logical block devices as seen by the operating system (often involving a volume manager, RAID controller, array manager, or suitable device driver), and the management of data and files that are stored on these logical block devices (a file system or other data storage).


title: ZFS

text: ZFS is unusual because, unlike most other storage systems, it unifies both of these roles and "acts as both the volume manager and the file system". Therefore, it has complete knowledge of both the physical disks and volumes (including their condition and status, their logical arrangement into volumes), and also of all the files stored on them. ZFS is designed to ensure (subject to suitable hardware) that data stored on disks cannot be lost due to physical errors or misprocessing by the hardware or operating system, or bit rot events and data corruption which may happen over time, and its complete control of the storage system is used to ensure that every step, whether related to file management or disk management, is verified, confirmed, corrected if needed, and optimized, in a way that storage controller cards and separate volume and file managers cannot achieve.


title: ZFS

text: ZFS also includes a mechanism for dataset and pool-level snapshots and replication, including snapshot cloning which is described by the FreeBSD documentation as one of its "most powerful features", having features that "even other file systems with snapshot functionality lack". Very large numbers of snapshots can be taken, without degrading performance, allowing snapshots to be used prior to risky system operations and software changes, or an entire production ("live") file system to be fully snapshotted several times an hour, in order to mitigate data loss due to user error or malicious activity. Snapshots can be rolled back "live" or previous file system states can be viewed, even on very large file systems, leading to savings in comparison to formal backup and restore processes. Snapshots can also be cloned to form new independent file systems. A pool level snapshot (known as a "checkpoint") is available which allows rollback of operations that may affect the entire pool's structure, or which add or remove entire datasets.


title: ZFS

text: In 1987, AT&T Corporation and Sun announced that they were collaborating on a project to merge the most popular Unix variants on the market at that time: Berkeley Software Distribution, UNIX System V, and Xenix. This became Unix System V Release 4 (SVR4). The project was released under the name Solaris, which became the successor to SunOS 4 (although SunOS 4.1."x" micro releases were retroactively named "Solaris 1").


title: ZFS

text: ZFS was designed and implemented by a team at Sun led by Jeff Bonwick, Bill Moore and Matthew Ahrens. It was announced on September 14, 2004, but development started in 2001. Source code for ZFS was integrated into the main trunk of Solaris development on October 31, 2005, and released for developers as part of build 27 of OpenSolaris on November 16, 2005. In June 2006, Sun announced that ZFS was included in the mainstream 6/06 update to Solaris 10.


title: ZFS

text: Solaris was originally developed as proprietary software, but Sun Microsystems was an early commercial proponent of open source software and in June 2005 released most of the Solaris codebase under the CDDL license and founded the OpenSolaris open-source project. In Solaris 10 6/06 ("U2"), Sun added the ZFS file system and during the next 5 years frequently updated ZFS with new features. ZFS was ported to Linux, Mac OS X (continued as MacZFS) and FreeBSD, under this open source license.


title: ZFS

text: The name at one point was said to stand for "Zettabyte File System", but by 2006, the name was no longer considered to be an abbreviation. A ZFS file system can store up to 256 quadrillion zettabytes (ZB).


title: ZFS

text: In September 2007, NetApp sued Sun claiming that ZFS infringed some of NetApp's patents on Write Anywhere File Layout. Sun counter-sued in October the same year claiming the opposite. The lawsuits were ended in 2010 with an undisclosed settlement.


title: ZFS

text: Ported versions of ZFS began to appear in 2005. After the Sun acquisition by Oracle in 2010, Oracle's version of ZFS became closed source and development of open-source versions proceeded independently, coordinated by OpenZFS from 2013.


title: ZFS

text: One major feature that distinguishes ZFS from other file systems is that it is designed with a focus on data integrity by protecting the user's data on disk against silent data corruption caused by data degradation, power surges (voltage spikes), bugs in disk firmware, phantom writes (the previous write did not make it to disk), misdirected reads/writes (the disk accesses the wrong block), DMA parity errors between the array and server memory or from the driver (since the checksum validates data inside the array), driver errors (data winds up in the wrong buffer inside the kernel), accidental overwrites (such as swapping to a live file system), etc.


title: ZFS

text: A 1999 study showed that neither any of the then-major and widespread filesystems (such as UFS, Ext, XFS, JFS, or NTFS), nor hardware RAID (which has some issues with data integrity) provided sufficient protection against data corruption problems. Initial research indicates that ZFS protects data better than earlier efforts.


title: ZFS

text: Within ZFS, data integrity is achieved by using a Fletcher-based checksum or a SHA-256 hash throughout the file system tree. Each block of data is checksummed and the checksum value is then saved in the pointer to that block—rather than at the actual block itself. Next, the block pointer is checksummed, with the value being saved at "its" pointer. This checksumming continues all the way up the file system's data hierarchy to the root node, which is also checksummed, thus creating a Merkle tree. In-flight data corruption or phantom reads/writes (the data written/read checksums correctly but is actually wrong) are undetectable by most filesystems as they store the checksum with the data. ZFS stores the checksum of each block in its parent block pointer so the entire pool self-validates.


title: ZFS

text: When a block is accessed, regardless of whether it is data or meta-data, its checksum is calculated and compared with the stored checksum value of what it "should" be. If the checksums match, the data are passed up the programming stack to the process that asked for it; if the values do not match, then ZFS can heal the data if the storage pool provides data redundancy (such as with internal mirroring), assuming that the copy of data is undamaged and with matching checksums. It is optionally possible to provide additional in-pool redundancy by specifying (or ), which means that data will be stored twice (or three times) on the disk, effectively halving (or, for , reducing to one third) the storage capacity of the disk. Additionally some kinds of data used by ZFS to manage the pool are stored multiple times by default for safety, even with the default copies=1 setting.


title: ZFS

text: If other copies of the damaged data exist or can be reconstructed from checksums and parity data, ZFS will use a copy of the data (or recreate it via a RAID recovery mechanism), and recalculate the checksum—ideally resulting in the reproduction of the originally expected value. If the data passes this integrity check, the system can then update all faulty copies with known-good data and redundancy will be restored.


title: ZFS

text: Consistency of data held in memory, such as cached data in the ARC, is not checked by default, as ZFS is expected to run on enterprise-quality hardware with error correcting RAM, but the capability to check in-memory data exists and can be enabled using "debug flags".


title: ZFS

text: For ZFS to be able to guarantee data integrity, it needs multiple copies of the data, usually spread across multiple disks. Typically this is achieved by using either a RAID controller or so-called "soft" RAID (built into a file system).


title: ZFS

text: While ZFS "can" work with hardware RAID devices, ZFS will usually work more efficiently and with greater data protection if it has raw access to all storage devices. ZFS relies on the disk for an honest view to determine the moment data is confirmed as safely written and it has numerous algorithms designed to optimize its use of caching, cache flushing, and disk handling.


title: ZFS

text: Disks connected to the system using a hardware, firmware, other "soft" RAID, or any other controller that modifies the ZFS-to-disk I/O path will affect ZFS performance and data integrity. If a third-party device performs caching or presents drives to ZFS as a single system without the low level view ZFS relies upon, there is a much greater chance that the system will perform "less" optimally and that ZFS will be less likely to prevent failures, recover from failures more slowly, or lose data due to a write failure. For example, if a hardware RAID card is used, ZFS may not be able to: determine the condition of disks; determine if the RAID array is degraded or rebuilding; detect all data corruption; place data optimally across the disks; make selective repairs; control how repairs are balanced with ongoing use; or make repairs that ZFS could usually undertake. The hardware RAID card will interfere with ZFS' algorithms. RAID controllers also usually add controller-dependent data to the drives which prevents software RAID from accessing the user data. In the case of a hardware RAID controller failure, it may be possible to read the data with another compatible controller, but this isn't always possible and a replacement may not be available. Alternate hardware RAID controllers may not understand the original manufacturer's custom data required to manage and restore an array.


title: ZFS

text: Unlike most other systems where RAID cards or similar hardware can offload resources and processing to enhance performance and reliability, with ZFS it is strongly recommended that these methods "not" be used as they typically "reduce" the system's performance and reliability.


title: ZFS

text: If disks must be attached through a RAID or other controller, it is recommended to minimize the amount of processing done in the controller by using a plain HBA (host adapter), a simple fanout card, or configure the card in JBOD mode (i.e. turn off RAID and caching functions), to allow devices to be attached with minimal changes in the ZFS-to-disk I/O pathway. A RAID card in JBOD mode may still interfere if it has a cache or, depending upon its design, may detach drives that do not respond in time (as has been seen with many energy-efficient consumer-grade hard drives), and as such, may require Time-Limited Error Recovery (TLER)/CCTL/ERC-enabled drives to prevent drive dropouts, so not all cards are suitable even with RAID functions disabled.


title: ZFS

text: Instead of hardware RAID, ZFS employs "soft" RAID, offering "RAID-Z" (parity based like RAID 5 and similar) and disk mirroring (similar to RAID 1). The schemes are highly flexible.


title: ZFS

text: RAID-Z is a data/parity distribution scheme like RAID-5, but uses dynamic stripe width: every block is its own RAID stripe, regardless of blocksize, resulting in every RAID-Z write being a full-stripe write. This, when combined with the copy-on-write transactional semantics of ZFS, eliminates the write hole error. RAID-Z is also faster than traditional RAID 5 because it does not need to perform the usual read-modify-write sequence.


title: ZFS

text: As all stripes are of different sizes, RAID-Z reconstruction has to traverse the filesystem metadata to determine the actual RAID-Z geometry. This would be impossible if the filesystem and the RAID array were separate products, whereas it becomes feasible when there is an integrated view of the logical and physical structure of the data. Going through the metadata means that ZFS can validate every block against its 256-bit checksum as it goes, whereas traditional RAID products usually cannot do this.


title: ZFS

text: In addition to handling whole-disk failures, RAID-Z can also detect and correct silent data corruption, offering "self-healing data": when reading a RAID-Z block, ZFS compares it against its checksum, and if the data disks did not return the right answer, ZFS reads the parity and then figures out which disk returned bad data. Then, it repairs the damaged data and returns good data to the requestor.


title: ZFS

text: RAID-Z and mirroring do not require any special hardware: they do not need NVRAM for reliability, and they do not need write buffering for good performance or data protection. With RAID-Z, ZFS provides fast, reliable storage using cheap, commodity disks.


title: ZFS

text: There are five different RAID-Z modes: "striping" (similar to RAID 0, offers no redundancy), "RAID-Z1" (similar to RAID 5, allows one disk to fail), "RAID-Z2" (similar to RAID 6, allows two disks to fail), "RAID-Z3" (a RAID 7 configuration, allows three disks to fail), and mirroring (similar to RAID 1, allows all but one disk to fail).


title: ZFS

text: The need for RAID-Z3 arose in the early 2000s as multi-terabyte capacity drives became more common. This increase in capacity—without a corresponding increase in throughput speeds—meant that rebuilding an array due to a failed drive could "easily take weeks or months" to complete. During this time, the older disks in the array will be stressed by the additional workload, which could result in data corruption or drive failure. By increasing parity, RAID-Z3 reduces the chance of data loss by simply increasing redundancy.


title: ZFS

text: ZFS has no tool equivalent to fsck (the standard Unix and Linux data checking and repair tool for file systems). Instead, ZFS has a built-in scrub function which regularly examines all data and repairs silent corruption and other problems. Some differences are:


title: ZFS

text: The official recommendation from Sun/Oracle is to scrub enterprise-level disks once a month, and cheaper commodity disks once a week.


title: ZFS

text: ZFS is a 128-bit file system, so it can address 1.84 × 10 times more data than 64-bit systems such as Btrfs. The maximum limits of ZFS are designed to be so large that they should never be encountered in practice. For instance, fully populating a single zpool with 2 bits of data would require 3×10 TB hard disk drives.


title: ZFS

text: With Oracle Solaris, the encryption capability in ZFS is embedded into the I/O pipeline. During writes, a block may be compressed, encrypted, checksummed and then deduplicated, in that order. The policy for encryption is set at the dataset level when datasets (file systems or ZVOLs) are created. The wrapping keys provided by the user/administrator can be changed at any time without taking the file system offline. The default behaviour is for the wrapping key to be inherited by any child data sets. The data encryption keys are randomly generated at dataset creation time. Only descendant datasets (snapshots and clones) share data encryption keys. A command to switch to a new data encryption key for the clone or at any time is provided—this does not re-encrypt already existing data, instead utilising an encrypted master-key mechanism.


title: ZFS

text: ZFS will automatically allocate data storage across all vdevs in a pool (and all devices in each vdev) in a way that generally maximises the performance of the pool. ZFS will also update its write strategy to take account of new disks added to a pool, when they are added.


title: ZFS

text: As a general rule, ZFS allocates writes across vdevs based on the free space in each vdev. This ensures that vdevs which have proportionately less data already, are given more writes when new data is to be stored. This helps to ensure that as the pool becomes more used, the situation does not develop that some vdevs become full, forcing writes to occur on a limited number of devices. It also means that when data is read (and reads are much more frequent than writes in most uses), different parts of the data can be read from as many disks as possible at the same time, giving much higher read performance. Therefore, as a general rule, pools and vdevs should be managed and new storage added, so that the situation does not arise that some vdevs in a pool are almost full and others almost empty, as this will make the pool less efficient.


title: ZFS

text: Pools can have hot spares to compensate for failing disks. When mirroring, block devices can be grouped according to physical chassis, so that the filesystem can continue in the case of the failure of an entire chassis.


title: ZFS

text: Storage pool composition is not limited to similar devices, but can consist of ad-hoc, heterogeneous collections of devices, which ZFS seamlessly pools together, subsequently doling out space to as needed. Arbitrary storage device types can be added to existing pools to expand their size.


title: ZFS

text: The storage capacity of all vdevs is available to all of the file system instances in the zpool. A quota can be set to limit the amount of space a file system instance can occupy, and a reservation can be set to guarantee that space will be available to a file system instance.


title: ZFS

text: ZFS uses different layers of disk cache to speed up read and write operations. Ideally, all data should be stored in RAM, but that is usually too expensive. Therefore, data is automatically cached in a hierarchy to optimize performance versus cost; these are often called "hybrid storage pools". Frequently accessed data will be stored in RAM, and less frequently accessed data can be stored on slower media, such as solid state drives (SSDs). Data that is not often accessed is not cached and left on the slow hard drives. If old data is suddenly read a lot, ZFS will automatically move it to SSDs or to RAM.


title: ZFS

text: ZFS caching mechanisms include one each for reads and writes, and in each case, two levels of caching can exist, one in computer memory (RAM) and one on fast storage (usually solid state drives (SSDs)), for a total of four caches.


title: ZFS

text: A number of other caches, cache divisions, and queues also exist within ZFS. For example, each VDEV has its own data cache, and the ARC cache is divided between data stored by the user and metadata used by ZFS, with control over the balance between these.


title: ZFS

text: In OpenZFS 0.8 and later, it is possible to configure a Special VDEV class to preferentially store filesystem metadata, and optionally the Data Deduplication Table (DDT), and small filesystem blocks. This allows, for example, to create a Special VDEV on fast solid-state storage to store the metadata, while the regular file data is stored on spinning disks. This speeds up metadata-intensive operations such as filesystem traversal, scrub, and resilver, without the expense of storing the entire filesystem on solid-state storage.


title: ZFS

text: ZFS uses a copy-on-write transactional object model. All block pointers within the filesystem contain a 256-bit checksum or 256-bit hash (currently a choice between Fletcher-2, Fletcher-4, or SHA-256) of the target block, which is verified when the block is read. Blocks containing active data are never overwritten in place; instead, a new block is allocated, modified data is written to it, then any metadata blocks referencing it are similarly read, reallocated, and written. To reduce the overhead of this process, multiple updates are grouped into transaction groups, and ZIL (intent log) write cache is used when synchronous write semantics are required. The blocks are arranged in a tree, as are their checksums (see Merkle signature scheme).


title: ZFS

text: An advantage of copy-on-write is that, when ZFS writes new data, the blocks containing the old data can be retained, allowing a snapshot version of the file system to be maintained. ZFS snapshots are consistent (they reflect the entire data as it existed at a single point in time), and can be created extremely quickly, since all the data composing the snapshot is already stored, with the entire storage pool often snapshotted several times per hour. They are also space efficient, since any unchanged data is shared among the file system and its snapshots. Snapshots are inherently read-only, ensuring they will not be modified after creation, although they should not be relied on as a sole means of backup. Entire snapshots can be restored and also files and directories within snapshots.


title: ZFS

text: Writeable snapshots ("clones") can also be created, resulting in two independent file systems that share a set of blocks. As changes are made to any of the clone file systems, new data blocks are created to reflect those changes, but any unchanged blocks continue to be shared, no matter how many clones exist. This is an implementation of the Copy-on-write principle.


title: ZFS

text: ZFS file systems can be moved to other pools, also on remote hosts over the network, as the send command creates a stream representation of the file system's state. This stream can either describe complete contents of the file system at a given snapshot, or it can be a delta between snapshots. Computing the delta stream is very efficient, and its size depends on the number of blocks changed between the snapshots. This provides an efficient strategy, e.g., for synchronizing offsite backups or high availability mirrors of a pool.


title: ZFS

text: Dynamic striping across all devices to maximize throughput means that as additional devices are added to the zpool, the stripe width automatically expands to include them; thus, all disks in a pool are used, which balances the write load across them.


title: ZFS

text: ZFS uses variable-sized blocks, with 128 KB as the default size. Available features allow the administrator to tune the maximum block size which is used, as certain workloads do not perform well with large blocks. If data compression is enabled, variable block sizes are used. If a block can be compressed to fit into a smaller block size, the smaller size is used on the disk to use less storage and improve IO throughput (though at the cost of increased CPU use for the compression and decompression operations).


title: ZFS

text: In ZFS, filesystem manipulation within a storage pool is easier than volume manipulation within a traditional filesystem; the time and effort required to create or expand a ZFS filesystem is closer to that of making a new directory than it is to volume manipulation in some other systems.


title: ZFS

text: Pools and their associated ZFS file systems can be moved between different platform architectures, including systems implementing different byte orders. The ZFS block pointer format stores filesystem metadata in an endian-adaptive way; individual metadata blocks are written with the native byte order of the system writing the block. When reading, if the stored endianness does not match the endianness of the system, the metadata is byte-swapped in memory.


title: ZFS

text: This does not affect the stored data; as is usual in POSIX systems, files appear to applications as simple arrays of bytes, so applications creating and reading data remain responsible for doing so in a way independent of the underlying system's endianness.


title: ZFS

text: Data deduplication capabilities were added to the ZFS source repository at the end of October 2009, and relevant OpenSolaris ZFS development packages have been available since December 3, 2009 (build 128).


title: ZFS

text: Effective use of deduplication may require large RAM capacity; recommendations range between 1 and 5 GB of RAM for every TB of storage. An accurate assessment of the memory required for deduplication is made by referring to the number of unique blocks in the pool, and the number of bytes on disk and in RAM ("core") required to store each record—these figures are reported by inbuilt commands such as codice_1 and codice_2. Insufficient physical memory or lack of ZFS cache can result in virtual memory thrashing when using deduplication, which can cause performance to plummet, or result in complete memory starvation. Because deduplication occurs at write-time, it is also very CPU-intensive and this can also significantly slow down a system.


title: ZFS

text: Other storage vendors use modified versions of ZFS to achieve very high data compression ratios. Two examples in 2012 were GreenBytes and Tegile. In May 2014, Oracle bought GreenBytes for its ZFS deduplication and replication technology.


title: ZFS

text: As described above, deduplication is usually "not" recommended due to its heavy resource requirements (especially RAM) and impact on performance (especially when writing), other than in specific circumstances where the system and data are well-suited to this space-saving technique.


title: ZFS

text: The authors of a 2010 study that examined the ability of file systems to detect and prevent data corruption, with particular focus on ZFS, observed that ZFS itself is effective in detecting and correcting data errors on storage devices, but that it assumes data in RAM is "safe", and not prone to error. The study comments that "a single bit flip in memory causes a small but non-negligible percentage of runs to experience a failure, with the probability of committing bad data to disk varying from 0% to 3.6% (according to the workload)", and that when ZFS caches pages or stores copies of metadata in RAM, or holds data in its "dirty" cache for writing to disk, no test is made whether the checksums still match the data at the point of use.


title: ZFS

text: Historically, ZFS has not shipped with tools such as fsck to repair damaged file systems, because the file system itself was designed to self-repair, so long as it had been built with sufficient attention to the design of storage and redundancy of data. If the pool was compromised because of poor hardware, inadequate design or redundancy, or unfortunate mishap, to the point that ZFS was unable to mount the pool, traditionally there were no tools which allowed an end-user to attempt partial salvage of the stored data. This led to threads in online forums where ZFS developers sometimes tried to provide ad-hoc help to home and other small scale users, facing loss of data due to their inadequate design or poor system management.


title: ZFS

text: Oracle Corporation ceased the public development of both ZFS and OpenSolaris after the acquisition of Sun in 2010. Some developers forked the last public release of OpenSolaris as the Illumos project. Because of the significant advantages present in ZFS, it has been ported to several different platforms with different features and commands. For coordinating the development efforts and to avoid fragmentation, OpenZFS was founded in 2013.


title: ZFS

text: According to Matt Ahrens, one of the main architects of ZFS, over 50% of the original OpenSolaris ZFS code has been replaced in OpenZFS with community contributions as of 2019, making “Oracle ZFS” and “OpenZFS” politically and technologically incompatible.


title: ZFS

text: In January 2010, Oracle Corporation acquired Sun Microsystems, and quickly discontinued the OpenSolaris distribution and the open source development model. In August 2010, Oracle discontinued providing public updates to the source code of the Solaris OS/Networking repository, effectively turning Solaris 11 back into a closed source proprietary operating system.


title: ZFS

text: In response to the changing landscape of Solaris and OpenSolaris, the illumos project was launched via webinar on Thursday, August 3, 2010, as a community effort of some core Solaris engineers to continue developing the open source version of Solaris, and complete the open sourcing of those parts not already open sourced by Sun. illumos was founded as a Foundation, the illumos Foundation, incorporated in the State of California as a 501(c)6 trade association. The original plan explicitly stated that illumos would not be a distribution or a fork. However, after Oracle announced discontinuing OpenSolaris, plans were made to fork the final version of the Solaris ON, allowing illumos to evolve into an operating system of its own. As part of OpenSolaris, an open source version of ZFS was therefore integral within illumos.


title: ZFS

text: ZFS was widely used within numerous platforms, as well as Solaris. Therefore, in 2013, the co-ordination of development work on the open source version of ZFS was passed to an umbrella project, "OpenZFS". The OpenZFS framework allows any interested parties to collaboratively develop the core ZFS codebase in common, while individually maintaining any specific extra code which ZFS requires to function and integrate within their own systems.


title: ZFS

text: "Note: The Solaris version under development by Sun since the release of Solaris 10 in 2005 was codenamed 'Nevada', and was derived from what was the OpenSolaris codebase. 'Solaris Nevada' is the codename for the next-generation Solaris OS to eventually succeed Solaris 10 and this new code was then pulled successively into new OpenSolaris 'Nevada' snapshot builds. OpenSolaris is now discontinued and OpenIndiana forked from it.


title: ZFS

text: A final build (b134) of OpenSolaris was published by Oracle (2010-Nov-12) as an upgrade path to Solaris 11 Express."


title: ZFS

text: List of Operating Systems, distributions and add-ons that support ZFS, the zpool version it supports, and the Solaris build they are based on (if any):


title: Gulliver's Travels (2010 film)

text: Gulliver's Travels is a 2010 American fantasy adventure comedy film directed by Rob Letterman in his live-action directorial debut, produced by John Davis and Gregory Goodman, written by Joe Stillman and Nicholas Stoller with music by Henry Jackman. It is very loosely based on Part One of the 1726 novel of the same name by Jonathan Swift, though the film takes place in the modern day. It stars Jack Black in the title role, Jason Segel, Emily Blunt, Amanda Peet, Billy Connolly, Chris O'Dowd, T.J Miller, James Corden and Catherine Tate, and is exclusively distributed by 20th Century Fox.


title: Gulliver's Travels (2010 film)

text: The film was theatrically released on December 25, 2010, in the United States. Even though the film received generally negative reviews, it earned $237.4 million on a $112 million budget. "Gulliver's Travels" was released on DVD and Blu-ray Disc on April 19, 2011, by 20th Century Fox Home Entertainment.


title: Gulliver's Travels (2010 film)

text: Deeply depressed at his dead-end job in the mail room of a New York City newspaper, Lemuel Gulliver decides to impress journalist Darcy Silverman. He convinces her he could write a report about his (false) extensive world "travels" saying his dream is to become a writer. After suffering writer's block and thinking that Darcy will not want to hang out with a "guy from the mailroom", Gulliver plagiarises a report from other publications on the internet. The next day, Darcy, impressed by his writing, presents Gulliver with a new task – to travel to the Bermuda Triangle and write an article about the legends of ships mysteriously disappearing there.


title: Gulliver's Travels (2010 film)

text: Upon arriving in Bermuda, Gulliver rents a ship and travels into the triangle. After falling asleep at the helm of his ship, Gulliver is caught in a freak storm and the ship is overwhelmed by a waterspout. Gulliver washes up unconscious on the shore of Lilliput, where he is immediately confirmed as a "beast" by the town's tiny people. After the citizens claim him to be dangerous because of his size, Gulliver is captured and imprisoned in a cave. There, he meets another prisoner named Horatio who was jailed by General Edward because he loves Princess Mary of Lilliput, despite Edward also pursuing her. After the island across from Lilliput, Blefuscia, orders some commandos to kidnap Princess Mary, Gulliver manages to break free of the plough-machine he is forced to work and then rescues the princess from being kidnapped. Gulliver also saves her father, King Theodore, from a fire by urinating on it.


title: Gulliver's Travels (2010 film)

text: Gulliver is declared a hero by Lilliput's citizens and lies that he is the President of Manhattan, says Yoda is his vice-president and a living legend in his homeland. Edward, however, becomes enraged due to the luxurious accommodations that have been built for Gulliver, and for being presented as an honorary general of the Lilliputian Army complete with uniform. The townspeople find Gulliver's boat and his things, when Gulliver receives angry voicemails from Darcy, who has to take his place and travel to Bermuda now, and she has found out about his plagiarism and now hates him. The next day, chaos ensues as the Blefuscian Navy lays siege to the city when Edward shuts down its defense system as an act of revenge for Gulliver's treatment. Gulliver defeats the armada, invulnerable to the cannonballs being fired at him (although he receives numerous welts on his stomach). Embarrassed once more, and with Mary no longer wanting to have anything to do with him, Edward defects to the Blefuscians and brings with him blueprints of a robot he had made from a page he'd seen from Gulliver's "" game manual. The Blefuscians secretly build the robot, with Edward as the pilot.


title: Gulliver's Travels (2010 film)

text: The Blefuscians invade Lilliput and the robot-wielding Edward makes Gulliver admit to the people that he is "just the guy from the mail-room" and nothing more. Edward banishes Gulliver to the shores of "the island where we dare not go" (Brobdingnag). There, he is snatched up by a "little" girl (Glumdalclitch) who towers over him. She captures him easily by trapping him inside a glass cup. When Gulliver wakes up, he finds himself in a pink dress in a bedroom of a doll house which begins to shake when the "little girl" pulls apart the wall of the bedroom who begins to stare emotionlessly and ominously at a tiny defenseless Gulliver. He then screams fearfully at the sight of the quiet giant "little" girl, she shoves a milk bottle in his mouth and forcefully feeds him excess milk. The girl treats him as a doll, playing with him roughly. Horatio, who has gone to find Gulliver after being spurned by Mary, reveals to Gulliver that Darcy was imprisoned by the Blefuscians after she was lost in the Bermuda Triangle in the same manner as Gulliver. Gulliver narrowly escapes with him, using a parachute that he took from the skeleton of a dead U.S. Air Force pilot sitting in the dollhouse.


title: Gulliver's Travels (2010 film)

text: Once again accepting a duel from Edward, this time not only for Lilliput's freedom but for its fate as well – as Edward threatens to destroy it should Gulliver fail – Gulliver ultimately defeats him with the assistance of Horatio, who disables the machine's electrocuting weapon. Horatio is hailed a hero and gets King Theodore's permission to court the princess. Edward, reaching the point of insanity, threatens to kill the princess, but the princess, finally having enough of Edward, punches the traitor in the face in frustration. When King Theodore decides to sentence all Blefuscians to the gallows or to prepare for war, Gulliver then helps to make peace between the rival island-nations by reciting Edwin Starr's "War" and he, along with Darcy, return to New York City on their repaired ship. The film ends with Gulliver, now a legitimate travel writer, taking Darcy to lunch while holding hands, after returning from another travel assignment.


title: Gulliver's Travels (2010 film)

text: In a January 2010 interview on "The Late Late Show with Craig Ferguson", Segel explained his character spends most of the film in Black's shirt pocket. The film features 7.1 surround audio in select theaters. The name of Liliput's rival country, Blefuscu, was also changed to Blefuscia. Filming of the Lilliput royal palace was at Blenheim Palace. Miniature 1:12 scale dolls' house furniture and accessories from Derbyshire firm The Dolls House Emporium were used to bring the movie alive with less need for special effects. Jonathan Swift, the original author of the novel that the film was loosely based on, is not mentioned during the credits, despite the titles mentioning that the film is not an original piece.


title: Gulliver's Travels (2010 film)

text: A soundtrack album of Henry Jackman's score was released by Varese Sarabande. Rock music and film themes that appear in the film include:


title: Gulliver's Travels (2010 film)

text: The official trailer for the film was released on June 3, 2010; and attached to "Marmaduke" a day after. The second trailer was released on November 5, 2010, and it is also attached with "Megamind". As a prize on the television show "", four of its contestants were able to watch the film before its release.


title: Gulliver's Travels (2010 film)

text: Originally scheduled for release on June 4, 2010, it was released on December 25, 2010. 20th Century Fox later announced on March 23, 2010, that the film would be converted to 3D. On December 13, 20th Century Fox announced that it would again move the release date, this time to December 25, 2010.


title: Gulliver's Travels (2010 film)

text: "Gulliver's Travels" was released on DVD and Blu-ray Disc on April 19, 2011, by 20th Century Fox Home Entertainment and it was released on Disney+ on May 21, 2021.


title: Gulliver's Travels (2010 film)

text: On review aggregation website Rotten Tomatoes, the film has an approval rating of 20% based on 120 reviews, with an average rating of 4.10/10. The site's critical consensus reads, "Though Jack Black is back doing what he does best, "Gulliver's Travels" largely fails to do any justice to its source material, relying instead on juvenile humor and special effects." On Metacritic, the film has a score of 33 out of 100 based on reviews from 32 critics, indicating "generally unfavorable reviews". Audiences polled by CinemaScore gave the film an average grade of "B−" on an A+ to F scale.


title: Gulliver's Travels (2010 film)

text: "The Hollywood Reporter" commented that "any sense of fun slowly drains away as the movie insists on highlighting effects over character and story" while "Time Out" gave it 2 out of 5 stars, commenting that the film "veers between the very mildly chucklesome and plain not funny." "The Christian Science Monitor" called it "a movie of such stupendous uninspiration" that it was "monumentally dreadful" and the "San Francisco Chronicle" called it "cute" but "sleep-inducing." "Slant Magazine" rated the film 1.5 out of 4 stars and "Empire" rated 2 out of 5 stars calling it "a low-grade comedy that'll have Jonathan Swift turning in his grave."


title: Gulliver's Travels (2010 film)

text: Other critics were less harsh, although still not praising of the film. Roger Ebert commented that knowing whom the film is for, and whom it is not for, might help viewers appreciate it. He awarded the film three out of four stars.


title: Gulliver's Travels (2010 film)

text: "Gulliver's Travels" opened to $6.3 million for its opening weekend, landing at #8 in the US; this ranks it as the 84th worst opening for a film with a wide release tracked by Box Office Mojo. The film grossed $42.8 million in the US and Canada and $194.6 million in other territories, for a worldwide total of $237.4 million against a production budget of $112 million.


title: Gulliver's Travels (2010 film)

text: Black received a Kids Choice Award nomination for favorite movie actor and lost to Johnny Depp's performance in "Alice in Wonderland".


title: Gulliver's Travels (2010 film)

text: Black was also nominated for a Golden Raspberry Award for Worst Actor, only to lose to Ashton Kutcher's performances in "Killers" and "Valentine's Day".


title: Designated Player Rule

text: The Designated Player Rule, nicknamed the Beckham Rule, allows Major League Soccer franchises to sign up to three players that would be considered outside their salary cap (either by offering the player higher wages or by paying a transfer fee for the player). The rule, which was adopted ahead of the 2007 MLS season, enables teams to compete for star players in the international football market. The rule is one of two mechanisms by which MLS teams may exceed their salary cap, the other being allocation money. As of December 2019, there have been 209 Designated Players in league history.


title: Designated Player Rule

text: The rule is informally named after David Beckham, in anticipation of MLS teams signing lucrative deals with internationally recognized players, after Beckham entered into negotiations to join the league. Beckham was the first player signed under this rule, signing a five-year contract with the Los Angeles Galaxy with a guaranteed annual salary of $6.5 million.


title: Designated Player Rule

text: The team salary cap was estimated to be around US$1.9 million in 2006, was $2.1 million in 2007, and was raised to $2.3 million for the 2008 season. As part of the 2010 Collective Bargaining Agreement between MLS and the MLS Players' Union, the 2010 salary cap was $2.55 million, with an automatic five percent increase each year until the expiration of the agreement at the end of the 2014 season.


title: Designated Player Rule

text: Starting with the 2012 season, the rule was changed with respect to younger players. MLS announced the changes in August 2011 after clubs expressed concern about signing young international players with no guarantees that they would develop into stars.


title: Designated Player Rule

text: The maximum budget charge for Designated Players over age 23 was increased to $368,750 for 2013, $387,500 in 2014, $436,250 in 2015, $457,500 in 2016, and $480,625 in 2017. The budget charge for those who join during the midseason transfer window has remained at one-half of the full-season cap charge since the inception of the rule. The budget charges for younger players have not changed since 2012.


title: Designated Player Rule

text: The rule is informally named after David Beckham, in anticipation of MLS teams signing lucrative deals with internationally recognized players of Beckham's caliber. Beckham was the first player to be signed under this rule, signing a lucrative contract with the Los Angeles Galaxy worth up to $250 million over five years, with direct guaranteed compensation from MLS and Galaxy at $6.5 million a year.


title: Jim Justice

text: James Conley Justice II (born April 27, 1951) is an American businessman and politician who has served as the 36th governor of West Virginia since 2017. Justice had a net worth of $1.2 billion in September 2018, making him the wealthiest person in West Virginia, though it has declined to $513.3 million as of October 2021. He inherited a coal mining business from his father and built a business empire with over 94 companies, including the Greenbrier, a luxury resort in White Sulphur Springs.


title: Jim Justice

text: In 2015, Justice announced his candidacy for governor in the 2016 West Virginia gubernatorial election. Although a registered Republican before running for governor, he ran as a Democrat and defeated the Republican nominee, Bill Cole. Less than seven months after taking office, Justice switched back to the Republican Party after announcing his plans at a rally with U.S. president Donald Trump in the state. In the 2020 gubernatorial race, he was reelected over Democratic challenger Ben Salango.


title: Jim Justice

text: James Conley Justice II was born in Charleston, West Virginia, the son of James Conley Justice and Edna Ruth ("née" Perry) Justice. Justice grew up in Raleigh County, West Virginia. He enrolled at the University of Tennessee on an athletic scholarship for golf, but transferred to Marshall University. At Marshall, he was a two-year captain on the Thundering Herd golf team. He earned his bachelor's degree and Master of Business Administration from Marshall.


title: Jim Justice

text: After college, Justice went into the family agriculture business. He founded Bluestone Farms in 1977, which now operates of farmland, and is the leading producer of grain on the East Coast of the United States. During that time, he also developed Stoney Brook Plantation, a 15,000-acre hunting and fishing preserve in Monroe County. Justice is a seven-time national corn growing champion. After his father's death in 1993, Justice inherited ownership of Bluestone Industries and Bluestone Coal Corporation. In 2009, he sold some of his coal business to the Russian company Mechel for $568 million. In 2015, after a huge drop in the price of coal led Mechel to close some of the mines, he bought the business back for $5 million. Since buying back the mine from Mechel, Justice reopened several of the mines and hired over 200 miners.


title: Jim Justice

text: Justice's mining companies have been scrutinized for alleged cases of safety violation and unpaid taxes; in 2016, "NPR" called him the nation's "top mine safety delinquent". Justice allegedly owed millions of dollars to the government in back taxes, and unpaid coal mining fees and fines: "His mining companies owe $15 million in six states, including property and minerals taxes, state coal severance and withholding taxes, and federal income, excise and unemployment taxes, as well as mine safety penalties, according to county, state and federal records." Two debt-related lawsuits were settled in 2019, and in 2020 mining companies Justice or his family owned agreed to pay $5 million in delinquent safety fines.


title: Jim Justice

text: According to a ProPublica investigation, Justice paid more than $128 million in judgments and settlements over his businesses' unpaid bills.


title: Jim Justice

text: Forbes estimates Justice's net worth at $513.3 million as of October 2021. Justice serves as the owner or chief executive officer of over 50 companies, including the Greenbrier in White Sulphur Springs, West Virginia, which he bought for $20.5 million in 2009, preventing its bankruptcy. He is in the process of building a new mountaintop golf course with golfers Jack Nicklaus, Gary Player, and Lee Trevino. Arnold Palmer was involved before his 2016 death.


title: Jim Justice

text: As of 2014, Justice owned 70 active mines in five states. His charitable activities have included $25 million for the James C. Justice National Scout Camp at The Summit Bechtel Family National Scout Reserve, $5 million for Marshall University, and $10 million to the Cleveland Clinic. Justice gives away more than $1 million in Christmas gifts annually through the Dream Tree for Kids campaign.


title: Jim Justice

text: Before taking office as governor, Justice resigned from all the executive positions he held. He placed his daughter Jill in charge of the Greenbrier and his son Jay in charge of his mining and agriculture businesses. He has said he will place all his assets in a blind trust, but that the process will take time because of their complexity. During the 2020 COVID-19 pandemic, Justice and his family's businesses received at least between $11 million and $24 million in aid through the Paycheck Protection Program. His luxury resort, the Greenbrier Hotel Corporation, received a loan of between $5 million and $10 million, but the company did not promise to retain any jobs in exchange for the aid.


title: Jim Justice

text: As governor of West Virginia, Justice is in charge of the state agencies that regulate many of his businesses.


title: Jim Justice

text: In 2015, Justice declared his candidacy for governor of West Virginia in the 2016 election as a member of the Democratic Party. He had been a registered member of the Republican Party until changing his registration in February 2015. This was his first time running for political office. In May 2016, Justice won the Democratic nomination for governor and ran against Republican nominee Bill Cole in the general election. On November 8, Justice won the election.


title: Jim Justice

text: In January 2019, Justice declared his candidacy for reelection. This time, he ran as a Republican, having changing his party registration after a 2017 rally with President Donald Trump. He defeated multiple challengers in the Republican primary.


title: Jim Justice

text: In the general election campaign, Justice focused on his COVID-19 response, the state's budget surplus, and his work on the substance abuse crisis. Several polls had him leading by a large margin over Kanawha County Commissioner Ben Salango in the months preceding Election Day. On November 3, 2020, he defeated Salango with over 63% of the vote to Salango's 30%. With his win, he became the first West Virginian Republican gubernatorial candidate to win since Cecil Underwood in 1996 and the first GOP incumbent to win a second term since Arch A. Moore Jr. in 1976.


title: Jim Justice

text: The United Mine Workers endorsed Salango after having endorsed Justice in 2016. But Justice was endorsed by the West Virginia Coal Association, which said he had "worked to protect the miners, increase coal production, and explore innovative ways to use coal for new products and downstream job opportunities".


title: Jim Justice

text: Justice took office as governor on January 16, 2017. He is known for using colorful metaphors and digs at political opponents.


title: Jim Justice

text: To improve West Virginia's budget situation, he has proposed raising the state's revenue by $450 million, primarily by increasing the consumer sales tax, reinstituting the business and occupation (B & O) tax, and establishing a "rich man's" tax. He also opposed plans to cut health and education spending. On April 13, 2017, while vetoing a budget bill passed by the West Virginia legislature, Justice said the bill was "nothing more than a bunch of political you-know-what" and showed a prop featuring bull feces on a print copy of the bill.


title: Jim Justice

text: On August 3, 2017, Justice announced that he had rejoined the Republican Party. He made the announcement at a rally hosted by President Donald Trump in Huntington and also confirmed his support for Trump. Justice said he was returning to the GOP because he could not support Trump as a member of the Democratic Party. The announcement came as a surprise to his own staff. This also made Justice the first Republican governor of West Virginia since Cecil Underwood in 2001.


title: Jim Justice

text: Even after switching to the Republican Party, Justice initially supported incumbent Democrat Joe Manchin for reelection in the 2018 Senate election in West Virginia. Later in the general election, Justice endorsed Republican Senate candidate Patrick Morrisey. In February 2021, when asked by "The New York Times" whether he planned to run against Manchin, Justice said, "No, I’m really not . . . [i]f I can continue to do good stuff for West Virginia, I’m going to do it, and then probably fade off into the sunset."


title: Jim Justice

text: In 2020, Justice signed into law the Critical Infrastructure Protection Act, which created felony penalties for protests targeting oil and gas facilities. The law, which was passed with the support of Dominion Energy, the West Virginia Oil and Natural Gas Association, and the American Fuel and Petrochemical Manufacturers trade association, was described by its sponsor John Kelly as having been "requested by the natural gas industry".


title: Jim Justice

text: In January 2022, Justice postponed his annual State of the State address because he had contracted COVID-19 and was isolating at home.


title: Jim Justice

text: Justice began his gubernatorial campaign and political career as a conservative Democrat. "Time" identified him as a moderate Democrat. He switched to the Republican Party a few months after taking office and declared his support for President Donald Trump.


title: Jim Justice

text: Justice campaigned and has governed with support for the coal industry. He does not support raising taxes but has supported increasing teachers' salaries, arguing that increased state revenue will pay for the increased budget spending. In 2017, Justice said that he opposed budget cuts and supported raising sales taxes. The libertarian Cato Institute gave Justice an "F" grade based on their positions, but Justice voiced his disagreement with the rating. Before Justice switched from a Democrat to a Republican, Senate President Mitch Carmichael called him "more Republican in his philosophies. Where he has gotten away from that a little bit is his tax-and-spend policies."


title: Jim Justice

text: In February 2021, Justice urged Senator Joe Manchin to vote for the $1.9 trillion stimulus package proposed by President Joe Biden, warning against being "fiscally responsible" and adding, "I don't really know exactly what the thinking could possibly be there. I mean, we got people that are really hurting."


title: Jim Justice

text: Justice had said that he does not support abortion, but that the Supreme Court had decided the issue. Later, he attended a rally supporting Amendment 1, a state constitutional amendment banning abortion once "Roe v. Wade" was overturned. He is considered pro-life and signed two anti-abortion bills into law.


title: Jim Justice

text: Justice supports gun ownership and limited gun laws. In 2018, he signed into a law a bill allowing gun owners to keep their guns locked in vehicles on their employers' property, a bill the NRA supported. He also signed a bill legalizing hunting on Sundays on private land.


title: Jim Justice

text: Justice supports West Virginia's Medicaid expansion, which was implemented by the previous governor under the Affordable Care Act.


title: Jim Justice

text: Justice has said that he respects the Supreme Court's decision on "Obergefell v. Hodges", which legalized same-sex marriage nationwide, and that it is settled law. In 2017, he opposed a bill that would have allowed businesses to refuse service to LGBTQ customers.


title: Jim Justice

text: According to the "Charleston Gazette–Mail", Justice has equivocated on the scientific consensus on global warming. In a 2016 interview with the paper, he said: "There's documentation that would give one concern, and I don't think you should ignore that. At the same time, I think there's an awful lot of research that still should be done . . . I surely wouldn't sit here and say I am a believer in global warming, but I wouldn't sit here and say that I am not concerned."


title: Jim Justice

text: At the beginning of his second term as governor, Justice said he was a believer in alternative energy, pointing to his welcoming of Clearway Energy Group to begin construction of a wind farm, which will increase state wind power by 15%. But he added, "it is frivolous for us to think that today our nation can go forward without coal or without gas. There will be a day we transition away from fossil fuels. But I frankly don’t believe that it is now."


title: Jim Justice

text: Despite being one of the poorest states in the nation, West Virginia was, early on, second only to Alaska in vaccine distribution for COVID-19. Since then, it has lagged behind the rest of the nation, ranking 40th in percentage of the population covered as of May 6, 2020. Justice encouraged West Virginians to get vaccinated with the slogan "Do It for Babydog", referring to his dog.


title: Jim Justice

text: Justice met his wife, Cathy ("née" Comer) in high school. They have two children. Justice and his wife are members of First Baptist Church in Beckley, a congregation of the American Baptist Churches USA. He is tall. Justice is a lifelong fan of the New Orleans Saints of the National Football League (NFL), and spent $30 million to develop a training facility for the team to use in 2014 at the Greenbrier. Until 2019, he hosted the Greenbrier Classic, a PGA Tour event, at the Greenbrier annually.


title: Jim Justice

text: Justice lives in Lewisburg, West Virginia. He was sued about his residency by former state house assistant minority whip Isaac Sponaugle on the basis that Justice did not live in the West Virginia Governor's Mansion in Charleston. The state constitution requires the governor to "reside at the seat of government", Charleston. The lawsuit was eventually put before the West Virginia State Supreme Court, which denied a motion for a writ of prohibition. Chief Justice Evan Jenkins defined "reside" in terms of statewide officeholders. On March 2, Justice resolved the lawsuit, agreeing to reside in Charleston and paying Sponaugle's legal fees.


title: Jim Justice

text: Since 1992, Justice has been president of Beckley Little League. His participation has helped the program expand to over 1,000 children playing on 80 teams.


title: Jim Justice

text: Having lived in Lewisburg since 2001, Justice has been the girls' basketball coach at Greenbrier East High School since 2003, winning the state championship in 2012. In 2011, he also became the head coach of the boys' basketball teams, a position from which he stepped down in September 2017. He was the only coach at the AAA level (the state's largest classification) to coach both the girls' and boys' basketball teams. Justice said that though he would put his business interests in a blind trust upon becoming governor, he would still coach basketball. Of the coaching position, he said, "There are three things I know that I can do, and that's shoot a shotgun, make a deal, and coach basketball. I'm excited about it." In February 2020, Justice apologized for calling the Woodrow Wilson High School girls' basketball players "a bunch of thugs" after a heated basketball game between Greenbrier East and Woodrow Wilson.


title: Old Course at St Andrews

text: The Old Course at St Andrews, also known as the Old Lady or the Grand Old Lady, is considered the oldest golf course.


title: Old Course at St Andrews

text: It is a public course over common land in St Andrews, Fife, Scotland and is held in trust by the St Andrews Links Trust under an act of Parliament. The Royal and Ancient Golf Club of St Andrews clubhouse sits adjacent to the first tee, although it is but one of many clubs (St Andrews Golf Club, The New Golf Club, St Regulus Ladies Golf Club and The St Rule Club are the others with clubhouses) that have playing privileges on the course, along with some other non-clubhouse owning clubs and the general public. Originally known as the "golfing grounds" of St Andrews, it was not until the New Course was opened in 1895 that it became known as the Old Course.


title: Old Course at St Andrews

text: The Old Course at St Andrews is considered by many to be the "home of golf" because the sport was first played on the Links at St Andrews in the early 15th century. Golf was becoming increasingly popular in Scotland until James II of Scotland banned the game in 1457 because he felt that young men were playing too much golf instead of practising their archery. The ban was upheld by James III, and remained in force until 1502, when James IV became a golfer himself and removed the ban.


title: Old Course at St Andrews

text: In 1552, Archbishop John Hamilton gave the townspeople of St Andrews the right to play on the links. In 1754, 22 noblemen, professors, and landowners founded the "Society of St Andrews Golfers". This society would eventually become the precursor to The R&A which is the governing body for golf everywhere outside of the United States and Mexico. St Andrews Links had a scare when they went bankrupt in 1797. The Town Council of St Andrews decided to allow rabbit farming on the golf course to challenge golf for popularity. Twenty years of legal battling between the golfers and rabbit farmers ended in 1821 when a local landowner and golfer named James Cheape of Strathtyrum bought the land and is credited with saving the links for golf.


title: Old Course at St Andrews

text: The course evolved without the help of any one architect for many years, though notable contributions to its design were made by Daw Anderson in the 1850s and Old Tom Morris (1865–1908), who designed the 1st and 18th holes. Originally, it was played over the same set of fairways out and back to the same holes. As interest in the game increased, groups of golfers would often be playing the same hole, but going in different directions.


title: Old Course at St Andrews

text: The Old Course was pivotal to the development of how the game is played today. For instance, in 1764, the course had 22 holes and the members would play the same hole going out and in with the exception of the 11th and 22nd holes. William St Clair of Roslin as the captain of "The Captain and Gentlemen Golfers" authorized changes to St Andrews on 4 October 1764. He decided that the first four and last four holes on the course were too short and should be combined into four total holes (two in and two out). St Andrews then had 18 holes and that was how the standard of 18 holes was created. Around 1863, Old Tom Morris had the 1st green separated from the 17th green, producing the current 18-hole layout with 7 double greens and 4 single greens. The Old Course is home of The Open Championship, the oldest of golf's major championships. The Old Course has hosted this major 30 times since 1873, most recently in 2022. The 30 Open Championships that the Old Course has hosted is more than any other course, and The Open is currently played there every five years.


title: Old Course at St Andrews

text: Bobby Jones (who later founded Augusta National) first played St Andrews in the 1921 Open Championship. During the third round, he infamously hit his ball into a bunker on the 11th hole. After he took four swings at the ball and still could not get out, he lost his temper and continued the round, but did not turn in his score card, disqualifying himself. However, he did continue to play in the fourth round. Six years later, when the Open Championship returned to St Andrews, Jones also returned. Not only did he win, he also became the first amateur to win back-to-back Open Championships. He won wire-to-wire, shooting a 285 (7-under-par), which was the lowest score at either a U.S. Open or Open Championship at the time. He ended up winning the tournament by a decisive six strokes.


title: Old Course at St Andrews

text: In 1930, Jones returned to St Andrews for the British Amateur. He won, beating Roger Wethered by a score of 7 and 6 in the final match. He subsequently won the other three majors, making him the only man in the history of the sport to win the Grand Slam. Jones went on to fall in love with the Old Course for the rest of his life. Years later, he said "If I had to select one course upon which to play the match of my life, I should have selected the Old Course." In 1958 the town of St Andrews gave Jones the key to the city; he was only the second American to receive the honour (after Benjamin Franklin in 1759). After he received the key, he said "I could take out of my life everything but my experiences here in St Andrews and I would still have had a rich and full life."


title: Old Course at St Andrews

text: ESPN has said of the course, "No other golf course has as many famous landmarks as (the Old Course) St. Andrews, its 112 bunkers and endless hills and hollows have been cursed for centuries, and many have their own names and legends." In 1949, the last bunker to be filled in on the course was Hull bunker on the 15th fairway.


title: Old Course at St Andrews

text: The Open has been staged at the Old Course at St Andrews 30 times. The following is a list of the champions:


title: Proboscidea

text: The Proboscidea (, from the Greek and the Latin "proboscis") are a taxonomic order of afrotherian mammals containing one living family (Elephantidae) and several extinct families. First described by J. Illiger in 1811, it encompasses the elephants and their close relatives. From the mid-Miocene onwards, most proboscideans were very large. The largest land mammal of all time may have been a proboscidean; "Palaeoloxodon namadicus" was up to at the shoulder and may have weighed up to , almost double the weight of some sauropods like "Diplodocus carnegii". The largest extant proboscidean is the African bush elephant, with a record of size of at the shoulder and . In addition to their enormous size, later proboscideans are distinguished by tusks and long, muscular trunks, which were less developed or absent in early proboscideans.


title: Proboscidea

text: Three species of elephant are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. Elephantidae is the only surviving family of the order Proboscidea; extinct members include the mastodons, gomphotheres and stegodonts. The family Elephantidae also contains several extinct groups, including the mammoths and straight-tusked elephants. The distinctive features of proboscideans include a trunk, tusks, and massive legs. Large ear flaps are present in some proboscideans, including elephants. Some also have tough but sensitive skin; others, like the woolly mammoth, have a coat. The trunk is used for breathing, bringing food and water to the mouth, and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. The pillar-like legs carry their great weight.


title: Proboscidea

text: The earliest known proboscidean is "Eritherium", followed by "Phosphatherium", a small animal about the size of a fox. Both date from late Paleocene deposits of Morocco.


title: Proboscidea

text: Proboscideans evolved in Africa, where they increased in size and diversity during the Eocene and early Oligocene. Proboscideans have evolved greatly over time through three major forms of radiation: radiation of primitive Lophodont forms, radiation of gomphotheres and stegodons, and radiation of elephantidae. These forms of radiation have illustrated that proboscideans characteristics such as trunk, large ears, and tusks have evolved and were appearing late in the modern form. Several primitive families from these epochs have been described, including the Numidotheriidae, Moeritheriidae, and Barytheriidae, all found exclusively in Africa. The Anthracobunidae from the Indian subcontinent were also believed to be a family of proboscideans, but were excluded from the Proboscidea by Shoshani and Tassy (2005) and have more recently been assigned to the Perissodactyla. When Africa became connected to Europe and Asia after the shrinking of the Tethys Sea, proboscideans migrated into Eurasia, with some families eventually reaching the Americas. Proboscideans found in Eurasia as well as Africa include the Deinotheriidae, which thrived during the Miocene and into the early Quaternary, "Stegolophodon", an early genus of the disputed family Stegodontidae; the highly diverse Gomphotheriidae and Amebelodontidae; and the Mammutidae, or mastodons.


title: Proboscidea

text: Most proboscideans are now extinct, including all species endemic to the Americas, Europe, and northern Asia. Many of these extinctions occurred during or shortly after the last glacial period. Recently extinct species include the gomphotheres in the Americas, the American mastodon of family Mammutidae in North America, numerous stegodonts in Asia, the mammoths throughout the Northern Hemisphere, and several species of dwarf elephants found on various islands scattered around the world.


title: Lists of extinct species

text: This page features lists of extinct species, organisms that have become extinct, either in the wild or completely disappeared from Earth.


title: Lists of extinct species

text: In actual theoretical practice, a species not definitely located in the wild in the last fifty years of current time is textually called "extinct".


title: Swing Low, Sweet Chariot

text: "Swing Low, Sweet Chariot" is an African-American spiritual song and one of the best-known Christian hymns. Originating in early oral and musical African-American traditions, the date it was composed is unknown. Performances by the Hampton Singers and the Fisk Jubilee Singers brought the song to the attention of wider audiences in the late 19th century. J. B. T. Marsh includes an early version of text and tune in his 1876 publication "The Story of the Jubilee Singers, with their Songs". The earliest known recording of "Swing Low, Sweet Chariot" was recorded in 1894, by the Standard Quartette.


title: Swing Low, Sweet Chariot

text: The song uses the theme of death to remind the audience of the glory that awaits in Heaven, when Christians believe they will transcend the earthly world of suffering and come to rest in their final home. Specifically, the text refers to the Old Testament account of the Prophet Elijah's ascent into Heaven by chariot.


title: Swing Low, Sweet Chariot

text: The stylistic elements and thematic content are highly typical to those of other spirituals. The song is characterized by its use of repetition as a key poetic element, powerful imagery, personal rhetoric, and potentially coded lyrics.


title: Swing Low, Sweet Chariot

text: "Swing Low, Sweet Chariot" was traditionally performed as a call-and response tune. Its free-form structure intentionally allows for improvisation and spur-of-the-moment changes made to bring the performers and audience to a state of ecstasy and connection with the Holy Spirit. The melody is pentatonic.


title: Swing Low, Sweet Chariot

text: In 2002, the US Library of Congress honored the song as one of 50 recordings chosen that year to be added to the National Recording Registry. It was also included in the list of "Songs of the Century", by the Recording Industry Association of America and the National Endowment for the Arts.


title: Swing Low, Sweet Chariot

text: "Swing Low, Sweet Chariot" was composed by Wallace Willis, a Choctaw freedman in the old Indian Territory in what is now Choctaw County, near the County seat of Hugo, Oklahoma sometime after 1865. He may have been inspired by the sight of the Red River, by which he was toiling, which reminded him of the Jordan River and of the Prophet Elijah being taken to heaven by a chariot (2 Kings 2:11). Some sources claim that this song and "Steal Away" (also sung by Willis) had lyrics that referred to the Underground Railroad, the freedom movement that helped black people escape from Southern slavery to the North and Canada.


title: Swing Low, Sweet Chariot

text: Alexander Reid, a minister at the Old Spencer Academy, a Choctaw boarding school, heard Willis singing these two songs and transcribed the words and melodies. He sent the music to the Jubilee Singers of Fisk University in Nashville, Tennessee. The Jubilee Singers popularized the songs during a tour of the United States and Europe.


title: Swing Low, Sweet Chariot

text: In 1939, Nazi Germany's Reich Music Examination Office added the song to a listing of "undesired and harmful" musical works.


title: Swing Low, Sweet Chariot

text: The song enjoyed a resurgence during the 1960s Civil Rights struggle and the folk revival; it was performed by a number of artists. Perhaps the most famous performance during this period was that by Joan Baez during the legendary 1969 Woodstock festival.


title: Swing Low, Sweet Chariot

text: Oklahoma State Senator Judy Eason McIntyre from Tulsa proposed a bill nominating "Swing Low, Sweet Chariot" as the Oklahoma State official gospel song in 2011. The bill was co-sponsored by the Oklahoma State Black Congressional Caucus. Oklahoma Governor Mary Fallin signed the bill into law on May 5, 2011, at a ceremony at the Oklahoma Cowboy Hall of Fame; making the song the official Oklahoma State Gospel Song.


title: Swing Low, Sweet Chariot

text: The content of the song is typical to the style of the spiritual in several ways: its use of imagery that provides a sense of immediacy to the historical and biblical past, the repetition of the key poetic element of the song (“Coming for to carry me home”), and the alteration between the refrain and the stanzas throughout.  The song alternates between first person and second person pronouns, stressing the relationship between the performer, the listener, and the events unfolding in the song. By directly calling to the listener in the second stanza (“If you get there before I do”) the audience is transformed into a creative device that serves to heighten the emotional urgency of the tune.


title: Swing Low, Sweet Chariot

text: The song was originally intended to be sung in a call-and-response, a format that draws from the heritage of African styles of music and is widely used in African-American churches today. A leader sings the differentiated lines, and the congregation replies “Coming for to carry me home” after each. This style of performing the spiritual can be heard in the existing recordings of the Fisk Jubilee Singers performing the tune. This call-and-response performance style is the most common form of spiritual.


title: Swing Low, Sweet Chariot

text: The simple, repetitive nature of the song, along with the fact that it was commonly performed without instrumental accompaniment, meant that spontaneous shifts in tempo, pitch, and emphasis were commonly made, leading the song in new and exciting directions intended to unify congregants with the Holy Spirit.


title: Swing Low, Sweet Chariot

text: Like other spirituals, “Swing Low Sweet Chariot” has been thought to contain coded meanings not immediately apparent to all listeners. American historian Charshee Charlotte Lawrence McIntyre argues that many spirituals make use of “metonymic devices,” or metaphors that have encoded meanings. She claims that throughout many traditional spirituals several recurring figures always carry a metonymic double meaning. These double meanings allowed enslaved people to safely communicate messages of hope, freedom, and specific plans for escape to one another under the watchful gaze of their captors. The double meanings encoded in “Swing Low, Sweet Chariot” are believed to be the Jordan River as representative of the first step to freedom from slavery, “home” as Africa, and Jesus as anyone who helps bring the enslaved to freedom. However, a definitive categorization of any such figures is impossible to make.


title: Swing Low, Sweet Chariot

text: A popular early recording was by the Fisk University Jubilee Quartet for Victor Records (No. 16453) on December 1, 1909, and two years later the Apollo Jubilee Quartette recorded the song on Monday, February 26, 1912, Columbia Records (A1169), New York City.


title: Swing Low, Sweet Chariot

text: Since then, numerous versions have been recorded including those by Bing Crosby (recorded April 25, 1938), Kenny Ball and His Jazzmen (included in the album "The Kenny Ball Show" – 1962), Louis Armstrong (for his album "Louis and the Good Book" – 1958), Sam Cooke (for his album "Swing Low" – 1961), Vince Hill (1993), Peggy Lee (1946), and Paul Robeson (recorded January 7, 1926 for Victor (No. 20068)).


title: Swing Low, Sweet Chariot

text: The jazz accordionist/composer John Serry Sr. recorded the composition with the jazz guitarist Tony Mottola


title: Swing Low, Sweet Chariot

text: as members of the Biviano Accordion & Rhythm Sextette in 1947 for Sonora Records on the album "Accordion Capers" (Sonora # MS 476).


title: Swing Low, Sweet Chariot

text: British rock musician Eric Clapton recorded a reggae version of the song for his 1975 studio album "There's One in Every Crowd". RSO Records released it with the B-side "Pretty Blue Eyes" as a seven-inch gramophone single in May the same year, produced by Tom Dowd. His version reached various singles charts, including Japan, the Netherlands, New Zealand and the United Kingdom.


title: Swing Low, Sweet Chariot

text: "Swing Low, Sweet Chariot" contains the lyrics, "I looked over Jordan and what did I see? Coming for to carry me home". Pink Floyd's 1977 song "Sheep", written by Roger Waters, makes reference to the song with the lyrics, "I've looked over Jordan and I have seen, things are not what they seem". A later 1992 song by Waters, "The Bravery of Being Out of Range", makes further reference to the song with the lyrics, "I looked over Jordan and what did I see? I saw a U.S. Marine in a pile of debris".


title: Swing Low, Sweet Chariot

text: "Swing Low, Sweet Chariot" has been sung by English rugby players and fans for some decades, and there are associated gestures, sometimes used in a drinking game, which requires those who wrongly perform the gestures to buy a round of drinks. Folk singer Joe Stead claimed he introduced it to the rugby fraternity as early as 1960 after hearing it from civil rights activist Paul Robeson. An article published in "Tatler" in 1966 described a "tradition" at the West Park bar at Twickenham of patrons singing the song whilst swaying as one, shoulder-to-shoulder. It became associated with the English national side, in particular, in 1988.


title: Swing Low, Sweet Chariot

text: The World Rugby Museum in 2020 unearthed archive footage of "Swing Low" being sung at Twickenham when Martin Offiah (nicknamed "Chariots" as a play-on-words referencing the 1981 film Chariots of Fire), played in the 1987 Middlesex Sevens tournament. The curator of the museum believes the crowd at Twickenham would already have known "Swing Low" because it had been sung in rugby clubs since the 1960s, with rude gestures illustrating the words.


title: Swing Low, Sweet Chariot

text: Coming into the last match of the 1988 season, against Ireland at Twickenham, England had lost 15 of their previous 23 matches in the Five Nations Championship. The Twickenham crowd had only seen one solitary England try in the previous two years and at half time against Ireland they were 0–3 down. However, during the second half England scored six tries to give them a 35–3 win. The official account of this occasion from England Rugby is that a group of fans from Market Bosworth rugby club in the West Stand started singing the song before it was taken up by the rest of the crowd. Another account states that a group of boys from Douai School were the ones in the crowd to begin singing the song before it was taken up by other fans. The song is still regularly sung at matches by English supporters.


title: Swing Low, Sweet Chariot

text: In 2020 the Rugby Football Union, in response to the increased interest in the Black Lives Matter movement after the murder of George Floyd, said it was "reviewing" fans' use of the song. Former rugby player Brian Moore and Prince Harry both argued that the song should no longer be sung in rugby contexts. Former Barbarian and Rugby League Hall of Fame player Martin Offiah shortly afterwards said that he thought the song should be retained as an opportunity to educate England's and other nationalities' rugby fans about racial discrimination and Black history. Former England player Maggie Alphonsi said "I think it's good the RFU are having a review, but I don't agree with it being banned". Prime Minister Boris Johnson said that the song should not be banned as people should "focus less on the symbols of discrimination".


title: Swing Low, Sweet Chariot

text: The song became the England Rugby World Cup theme for the 1991 Rugby World Cup, when performed by "Union featuring the England World Cup Squad". It reached number 16 on the UK singles chart.


title: Swing Low, Sweet Chariot

text: The song was then covered in 1995 for that year's tournament by British reggae duo China Black together with South African male choral group, Ladysmith Black Mambazo. It reached number 15 on the chart.


title: Swing Low, Sweet Chariot

text: 1999's tournament featured Russell Watson record a version (titled Swing Low '99) which had less success, only peaking at number 38 on the UK chart.


title: Swing Low, Sweet Chariot

text: The song enjoyed more success in 2003's tournament, but included the album "Homegrown", when recorded by UB40 and the United Colours of Sound. It originally peaked at number 23, but following England's victory in the tournament, the cover reached number 15. In the wake of the tournament, UB40 performed the song at a concert at the NEC Arena Birmingham that was attended by England rugby fans and captain Martin Johnson. The England national rugby union team returned from the 2003 Rugby World Cup triumph in Australia on a plane dubbed "Sweet Chariot".


title: Swing Low, Sweet Chariot

text: For the 2011 Rugby World Cup in New Zealand, all-girl group Our Lady Muse (O.L.M) released an England Rugby World Cup Song. An upbeat party anthem version of Swing Low, Sweet Chariot – The Song was premiered at the "Polo Rocks" concert in aid of The Prince's Trust.


title: Swing Low, Sweet Chariot

text: English singer Ella Eyre released a cover version of the song on September 7, 2015 as a digital download in association with England Rugby, to coincide with the 2015 Rugby World Cup, with the song raising money for England Rugby's All Schools programme. The song was produced by Glyn Aikins and Mojam, it peaked to number 134 on the UK Singles Chart and number 87 on the Scottish Singles Chart. A music video to accompany the release of "Swing Low, Sweet Chariot" was first released onto YouTube on September 10, 2015 at a total length of three minutes and ten seconds.


title: Swing Low, Sweet Chariot

text: Country and gospel artist, Josh Turner, released a cover of the song on the 2018 album, I Serve a Savior. The album was Turner's first release that contained mainly gospel music.


title: Poisson's equation

text: Poisson's equation is an elliptic partial differential equation of broad utility in theoretical physics. For example, the solution to Poisson's equation is the potential field caused by a given electric charge or mass density distribution; with the potential field known, one can then calculate electrostatic or gravitational (force) field. It is a generalization of Laplace's equation, which is also frequently seen in physics. The equation is named after French mathematician and physicist Siméon Denis Poisson.


title: Poisson's equation

text: Poisson's equation is formula_1 where formula_2 is the Laplace operator, and formula_3 and formula_4 are real or complex-valued functions on a manifold. Usually, formula_3 is given and formula_4 is sought. When the manifold is Euclidean space, the Laplace operator is often denoted as and so Poisson's equation is frequently written as formula_7


title: Poisson's equation

text: where the integral is over all of space. A general exposition of the Green's function for Poisson's equation is given in the article on the screened Poisson equation. There are various methods for numerical solution, such as the relaxation method, an iterative algorithm.


title: Poisson's equation

text: In the case of a gravitational field g due to an attracting massive object of density "ρ", Gauss's law for gravity in differential form can be used to obtain the corresponding Poisson equation for gravity,


title: Poisson's equation

text: Since the gravitational field is conservative (and irrotational), it can be expressed in terms of a scalar potential "Φ",


title: Poisson's equation

text: If the mass density is zero, Poisson's equation reduces to Laplace's equation. The corresponding Green's function can be used to calculate the potential at distance from a central point mass (i.e., the fundamental solution). In three dimensions the potential is


title: Poisson's equation

text: One of the cornerstones of electrostatics is setting up and solving problems described by the Poisson equation. Solving the Poisson equation amounts to finding the electric potential for a given charge distribution formula_16.


title: Poisson's equation

text: The mathematical details behind Poisson's equation in electrostatics are as follows (SI units are used rather than Gaussian units, which are also frequently used in electromagnetism).


title: Poisson's equation

text: Starting with Gauss's law for electricity (also one of Maxwell's equations) in differential form, one has


title: Poisson's equation

text: where formula_18 is the divergence operator, D = electric displacement field, and "ρ" = free charge volume density (describing charges brought from outside).


title: Poisson's equation

text: Assuming the medium is linear, isotropic, and homogeneous (see polarization density), we have the constitutive equation,


title: Poisson's equation

text: Substituting this into Gauss's law and assuming is spatially constant in the region of interest yields


title: Poisson's equation

text: where formula_21 is a total volume charge density. In electrostatics, we assume that there is no magnetic field (the argument that follows also holds in the presence of a constant magnetic field). Then, we have that


title: Poisson's equation

text: where is the curl operator. This equation means that we can write the electric field as the gradient of a scalar function (called the electric potential), since the curl of any gradient is zero. Thus we can write,


title: Poisson's equation

text: where the minus sign is introduced so that is identified as the electric potential energy per unit charge.


title: Poisson's equation

text: The derivation of Poisson's equation under these circumstances is straightforward. Substituting the potential gradient for the electric field,


title: Poisson's equation

text: Solving Poisson's equation for the potential requires knowing the charge density distribution. If the charge density is zero, then Laplace's equation results. If the charge density follows a Boltzmann distribution, then the Poisson-Boltzmann equation results. The Poisson–Boltzmann equation plays a role in the development of the Debye–Hückel theory of dilute electrolyte solutions.


title: Poisson's equation

text: Using Green's Function, the potential at distance from a central point charge (i.e., the Fundamental Solution) is:


title: Poisson's equation

text: which is Coulomb's law of electrostatics. (For historic reasons, and unlike gravity's model above, the formula_27 factor appears here and not in Gauss's law.)


title: Poisson's equation

text: The above discussion assumes that the magnetic field is not varying in time. The same Poisson equation arises even if it does vary in time, as long as the Coulomb gauge is used. In this more general context, computing is no longer sufficient to calculate E, since E also depends on the magnetic vector potential A, which must be independently computed. See Maxwell's equation in potential formulation for more on and A in Maxwell's equations and how Poisson's equation is obtained in this case.


title: Poisson's equation

text: Note that, for much greater than , the erf function approaches unity and the potential approaches the point charge potential


title: Poisson's equation

text: as one would expect. Furthermore, the error function approaches 1 extremely quickly as its argument increases; in practice for the relative error is smaller than one part in a thousand.


title: Poisson's equation

text: Surface reconstruction is an inverse problem. The goal is to digitally reconstruct a smooth surface based on a large number of points "p" (a point cloud) where each point also carries an estimate of the local surface normal n. Poisson's equation can be utilized to solve this problem with a technique called Poisson surface reconstruction.


title: Poisson's equation

text: The goal of this technique is to reconstruct an implicit function "f" whose value is zero at the points "p" and whose gradient at the points "p" equals the normal vectors n. The set of ("p", n) is thus modeled as a continuous vector field V. The implicit function "f" is found by integrating the vector field V. Since not every vector field is the gradient of a function, the problem may or may not have a solution: the necessary and sufficient condition for a smooth vector field V to be the gradient of a function "f" is that the curl of V must be identically zero. In case this condition is difficult to impose, it is still possible to perform a least-squares fit to minimize the difference between V and the gradient of "f".


title: Poisson's equation

text: In order to effectively apply Poisson's equation to the problem of surface reconstruction, it is necessary to find a good discretization of the vector field V. The basic approach is to bound the data with a finite difference grid. For a function valued at the nodes of such a grid, its gradient can be represented as valued on staggered grids, i.e. on grids whose nodes lie in between the nodes of the original grid. It is convenient to define three staggered grids, each shifted in one and only one direction corresponding to the components of the normal data. On each staggered grid we perform [trilinear interpolation] on the set of points. The interpolation weights are then used to distribute the magnitude of the associated component of "n" onto the nodes of the particular staggered grid cell containing "p". Kazhdan and coauthors give a more accurate method of discretization using an adaptive finite difference grid, i.e. the cells of the grid are smaller (the grid is more finely divided) where there are more data points. They suggest implementing this technique with an adaptive octree.


title: Mini–Mental State Examination

text: The Mini–Mental State Examination (MMSE) or Folstein test is a 30-point questionnaire that is used extensively in clinical and research settings to measure cognitive impairment. It is commonly used in medicine and allied health to screen for dementia. It is also used to estimate the severity and progression of cognitive impairment and to follow the course of cognitive changes in an individual over time; thus making it an effective way to document an individual's response to treatment. The MMSE's purpose has been not, on its own, to provide a diagnosis for any particular nosological entity.


title: Mini–Mental State Examination

text: Administration of the test takes between 5 and 10 minutes and examines functions including registration (repeating named prompts), attention and calculation, recall, language, ability to follow simple commands and orientation. It was originally introduced by Folstein "et al." in 1975, in order to differentiate organic from functional psychiatric patients but is very similar to, or even directly incorporates, tests which were in use previous to its publication. This test is not a mental status examination. The standard MMSE form which is currently published by Psychological Assessment Resources is based on its original 1975 conceptualization, with minor subsequent modifications by the authors.