title: Protein folding

text: Aggregated proteins are associated with prion-related illnesses such as Creutzfeldt–Jakob disease, bovine spongiform encephalopathy (mad cow disease), amyloid-related illnesses such as Alzheimer's disease and familial amyloid cardiomyopathy or polyneuropathy, as well as intracellular aggregation diseases such as Huntington's and Parkinson's disease. These age onset degenerative diseases are associated with the aggregation of misfolded proteins into insoluble, extracellular aggregates and/or intracellular inclusions including cross-β amyloid fibrils. It is not completely clear whether the aggregates are the cause or merely a reflection of the loss of protein homeostasis, the balance between synthesis, folding, aggregation and protein turnover. Recently the European Medicines Agency approved the use of Tafamidis or Vyndaqel (a kinetic stabilizer of tetrameric transthyretin) for the treatment of transthyretin amyloid diseases. This suggests that the process of amyloid fibril formation (and not the fibrils themselves) causes the degeneration of post-mitotic tissue in human amyloid diseases. Misfolding and excessive degradation instead of folding and function leads to a number of proteopathy diseases such as antitrypsin-associated emphysema, cystic fibrosis and the lysosomal storage diseases, where loss of function is the origin of the disorder. While protein replacement therapy has historically been used to correct the latter disorders, an emerging approach is to use pharmaceutical chaperones to fold mutated proteins to render them functional.


title: Protein folding

text: While inferences about protein folding can be made through mutation studies, typically, experimental techniques for studying protein folding rely on the gradual unfolding or folding of proteins and observing conformational changes using standard non-crystallographic techniques.


title: Protein folding

text: X-ray crystallography is one of the more efficient and important methods for attempting to decipher the three dimensional configuration of a folded protein. To be able to conduct X-ray crystallography, the protein under investigation must be located inside a crystal lattice. To place a protein inside a crystal lattice, one must have a suitable solvent for crystallization, obtain a pure protein at supersaturated levels in solution, and precipitate the crystals in solution. Once a protein is crystallized, X-ray beams can be concentrated through the crystal lattice which would diffract the beams or shoot them outwards in various directions. These exiting beams are correlated to the specific three-dimensional configuration of the protein enclosed within. The X-rays specifically interact with the electron clouds surrounding the individual atoms within the protein crystal lattice and produce a discernible diffraction pattern. Only by relating the electron density clouds with the amplitude of the X-rays can this pattern be read and lead to assumptions of the phases or phase angles involved that complicate this method. Without the relation established through a mathematical basis known as Fourier transform, the "phase problem" would render predicting the diffraction patterns very difficult. Emerging methods like multiple isomorphous replacement use the presence of a heavy metal ion to diffract the X-rays into a more predictable manner, reducing the number of variables involved and resolving the phase problem.


title: Protein folding

text: Fluorescence spectroscopy is a highly sensitive method for studying the folding state of proteins. Three amino acids, phenylalanine (Phe), tyrosine (Tyr) and tryptophan (Trp), have intrinsic fluorescence properties, but only Tyr and Trp are used experimentally because their quantum yields are high enough to give good fluorescence signals. Both Trp and Tyr are excited by a wavelength of 280 nm, whereas only Trp is excited by a wavelength of 295 nm. Because of their aromatic character, Trp and Tyr residues are often found fully or partially buried in the hydrophobic core of proteins, at the interface between two protein domains, or at the interface between subunits of oligomeric proteins. In this apolar environment, they have high quantum yields and therefore high fluorescence intensities. Upon disruption of the protein's tertiary or quaternary structure, these side chains become more exposed to the hydrophilic environment of the solvent, and their quantum yields decrease, leading to low fluorescence intensities. For Trp residues, the wavelength of their maximal fluorescence emission also depend on their environment.


title: Protein folding

text: Fluorescence spectroscopy can be used to characterize the equilibrium unfolding of proteins by measuring the variation in the intensity of fluorescence emission or in the wavelength of maximal emission as functions of a denaturant value. The denaturant can be a chemical molecule (urea, guanidinium hydrochloride), temperature, pH, pressure, etc. The equilibrium between the different but discrete protein states, i.e. native state, intermediate states, unfolded state, depends on the denaturant value; therefore, the global fluorescence signal of their equilibrium mixture also depends on this value. One thus obtains a profile relating the global protein signal to the denaturant value. The profile of equilibrium unfolding may enable one to detect and identify intermediates of unfolding. General equations have been developed by Hugues Bedouelle to obtain the thermodynamic parameters that characterize the unfolding equilibria for homomeric or heteromeric proteins, up to trimers and potentially tetramers, from such profiles. Fluorescence spectroscopy can be combined with fast-mixing devices such as stopped flow, to measure protein folding kinetics, generate a chevron plot and derive a Phi value analysis.


title: Protein folding

text: Circular dichroism is one of the most general and basic tools to study protein folding. Circular dichroism spectroscopy measures the absorption of circularly polarized light. In proteins, structures such as alpha helices and beta sheets are chiral, and thus absorb such light. The absorption of this light acts as a marker of the degree of foldedness of the protein ensemble. This technique has been used to measure equilibrium unfolding of the protein by measuring the change in this absorption as a function of denaturant concentration or temperature. A denaturant melt measures the free energy of unfolding as well as the protein's m value, or denaturant dependence. A temperature melt measures the denaturation temperature (Tm) of the protein. As for fluorescence spectroscopy, circular-dichroism spectroscopy can be combined with fast-mixing devices such as stopped flow to measure protein folding kinetics and to generate chevron plots.


title: Protein folding

text: The more recent developments of vibrational circular dichroism (VCD) techniques for proteins, currently involving Fourier transform (FT) instruments, provide powerful means for determining protein conformations in solution even for very large protein molecules. Such VCD studies of proteins can be combined with X-ray diffraction data for protein crystals, FT-IR data for protein solutions in heavy water (DO), or quantum computations.


title: Protein folding

text: Protein nuclear magnetic resonance (NMR) is able to collect protein structural data by inducing a magnet field through samples of concentrated protein. In NMR, depending on the chemical environment, certain nuclei will absorb specific radio-frequencies. Because protein structural changes operate on a time scale from ns to ms, NMR is especially equipped to study intermediate structures in timescales of ps to s. Some of the main techniques for studying proteins structure and non-folding protein structural changes include COSY, TOCSY, HSQC, time relaxation (T1 & T2), and NOE. NOE is especially useful because magnetization transfers can be observed between spatially proximal hydrogens are observed. Different NMR experiments have varying degrees of timescale sensitivity that are appropriate for different protein structural changes. NOE can pick up bond vibrations or side chain rotations, however, NOE is too sensitive to pick up protein folding because it occurs at larger timescale.


title: Protein folding

text: Because protein folding takes place in about 50 to 3000 s CPMG Relaxation dispersion and chemical exchange saturation transfer have become some of the primary techniques for NMR analysis of folding. In addition, both techniques are used to uncover excited intermediate states in the protein folding landscape. To do this, CPMG Relaxation dispersion takes advantage of the spin echo phenomenon. This technique exposes the target nuclei to a 90 pulse followed by one or more 180 pulses. As the nuclei refocus, a broad distribution indicates the target nuclei is involved in an intermediate excited state. By looking at Relaxation dispersion plots the data collect information on the thermodynamics and kinetics between the excited and ground. Saturation Transfer measures changes in signal from the ground state as excited states become perturbed. It uses weak radio frequency irradiation to saturate the excited state of a particular nuclei which transfers its saturation to the ground state. This signal is amplified by decreasing the magnetization (and the signal) of the ground state.


title: Protein folding

text: The main limitations in NMR is that its resolution decreases with proteins that are larger than 25 kDa and is not as detailed as X-ray crystallography. Additionally, protein NMR analysis is quite difficult and can propose multiple solutions from the same NMR spectrum.


title: Protein folding

text: In a study focused on the folding of an amyotrophic lateral sclerosis involved protein SOD1, excited intermediates were studied with relaxation dispersion and Saturation transfer. SOD1 had been previously tied to many disease causing mutants which were assumed to be involved in protein aggregation, however the mechanism was still unknown. By using Relaxation Dispersion and Saturation Transfer experiments many excited intermediate states were uncovered misfolding in the SOD1 mutants.


title: Protein folding

text: Dual polarisation interferometry is a surface-based technique for measuring the optical properties of molecular layers. When used to characterize protein folding, it measures the conformation by determining the overall size of a monolayer of the protein and its density in real time at sub-Angstrom resolution, although real-time measurement of the kinetics of protein folding are limited to processes that occur slower than ~10 Hz. Similar to circular dichroism, the stimulus for folding can be a denaturant or temperature.


title: Protein folding

text: The study of protein folding has been greatly advanced in recent years by the development of fast, time-resolved techniques. Experimenters rapidly trigger the folding of a sample of unfolded protein and observe the resulting dynamics. Fast techniques in use include neutron scattering, ultrafast mixing of solutions, photochemical methods, and laser temperature jump spectroscopy. Among the many scientists who have contributed to the development of these techniques are Jeremy Cook, Heinrich Roder, Harry Gray, Martin Gruebele, Brian Dyer, William Eaton, Sheena Radford, Chris Dobson, Alan Fersht, Bengt Nölting and Lars Konermann.


title: Protein folding

text: Proteolysis is routinely used to probe the fraction unfolded under a wide range of solution conditions (e.g. fast parallel proteolysis (FASTpp).


title: Protein folding

text: Single molecule techniques such as optical tweezers and AFM have been used to understand protein folding mechanisms of isolated proteins as well as proteins with chaperones. Optical tweezers have been used to stretch single protein molecules from their C- and N-termini and unfold them to allow study of the subsequent refolding. The technique allows one to measure folding rates at single-molecule level; for example, optical tweezers have been recently applied to study folding and unfolding of proteins involved in blood coagulation. von Willebrand factor (vWF) is a protein with an essential role in blood clot formation process. It discovered – using single molecule optical tweezers measurement – that calcium-bound vWF acts as a shear force sensor in the blood. Shear force leads to unfolding of the A2 domain of vWF, whose refolding rate is dramatically enhanced in the presence of calcium. Recently, it was also shown that the simple src SH3 domain accesses multiple unfolding pathways under force.


title: Protein folding

text: Biotin painting enables condition-specific cellular snapshots of (un)folded proteins. Biotin 'painting' shows a bias towards predicted Intrinsically disordered proteins.


title: Protein folding

text: Computational studies of protein folding includes three main aspects related to the prediction of protein stability, kinetics, and structure. A 2013 review summarizes the available computational methods for protein folding.


title: Protein folding

text: In 1969, Cyrus Levinthal noted that, because of the very large number of degrees of freedom in an unfolded polypeptide chain, the molecule has an astronomical number of possible conformations. An estimate of 3 or 10 was made in one of his papers. Levinthal's paradox is a thought experiment based on the observation that if a protein were folded by sequential sampling of all possible conformations, it would take an astronomical amount of time to do so, even if the conformations were sampled at a rapid rate (on the nanosecond or picosecond scale). Based upon the observation that proteins fold much faster than this, Levinthal then proposed that a random conformational search does not occur, and the protein must, therefore, fold through a series of meta-stable intermediate states.


title: Protein folding

text: The configuration space of a protein during folding can be visualized as an energy landscape. According to Joseph Bryngelson and Peter Wolynes, proteins follow the "principle of minimal frustration", meaning that naturally evolved proteins have optimized their folding energy landscapes, and that nature has chosen amino acid sequences so that the folded state of the protein is sufficiently stable. In addition, the acquisition of the folded state had to become a sufficiently fast process. Even though nature has reduced the level of "frustration" in proteins, some degree of it remains up to now as can be observed in the presence of local minima in the energy landscape of proteins.


title: Protein folding

text: A consequence of these evolutionarily selected sequences is that proteins are generally thought to have globally "funneled energy landscapes" (a term coined by José Onuchic) that are largely directed toward the native state. This "folding funnel" landscape allows the protein to fold to the native state through any of a large number of pathways and intermediates, rather than being restricted to a single mechanism. The theory is supported by both computational simulations of model proteins and experimental studies, and it has been used to improve methods for protein structure prediction and design. The description of protein folding by the leveling free-energy landscape is also consistent with the 2nd law of thermodynamics. Physically, thinking of landscapes in terms of visualizable potential or total energy surfaces simply with maxima, saddle points, minima, and funnels, rather like geographic landscapes, is perhaps a little misleading. The relevant description is really a high-dimensional phase space in which manifolds might take a variety of more complicated topological forms.


title: Protein folding

text: The unfolded polypeptide chain begins at the top of the funnel where it may assume the largest number of unfolded variations and is in its highest energy state. Energy landscapes such as these indicate that there are a large number of initial possibilities, but only a single native state is possible; however, it does not reveal the numerous folding pathways that are possible. A different molecule of the same exact protein may be able to follow marginally different folding pathways, seeking different lower energy intermediates, as long as the same native structure is reached. Different pathways may have different frequencies of utilization depending on the thermodynamic favorability of each pathway. This means that if one pathway is found to be more thermodynamically favorable than another, it is likely to be used more frequently in the pursuit of the native structure. As the protein begins to fold and assume its various conformations, it always seeks a more thermodynamically favorable structure than before and thus continues through the energy funnel. Formation of secondary structures is a strong indication of increased stability within the protein, and only one combination of secondary structures assumed by the polypeptide backbone will have the lowest energy and therefore be present in the native state of the protein. Among the first structures to form once the polypeptide begins to fold are alpha helices and beta turns, where alpha helices can form in as little as 100 nanoseconds and beta turns in 1 microsecond.


title: Protein folding

text: There exists a saddle point in the energy funnel landscape where the transition state for a particular protein is found. The transition state in the energy funnel diagram is the conformation that must be assumed by every molecule of that protein if the protein wishes to finally assume the native structure. No protein may assume the native structure without first passing through the transition state. The transition state can be referred to as a variant or premature form of the native state rather than just another intermediary step. The folding of the transition state is shown to be rate-determining, and even though it exists in a higher energy state than the native fold, it greatly resembles the native structure. Within the transition state, there exists a nucleus around which the protein is able to fold, formed by a process referred to as "nucleation condensation" where the structure begins to collapse onto the nucleus.


title: Protein folding

text: "De novo" or "ab initio" techniques for computational protein structure prediction can be used for simulating various aspects of protein folding. Molecular Dynamics (MD) was used in simulations of protein folding and dynamics in silico. First equilibrium folding simulations were done using implicit solvent model and umbrella sampling. Because of computational cost, ab initio MD folding simulations with explicit water are limited to peptides and very small proteins. MD simulations of larger proteins remain restricted to dynamics of the experimental structure or its high-temperature unfolding. Long-time folding processes (beyond about 1 millisecond), like folding of small-size proteins (about 50 residues) or larger, can be accessed using coarse-grained models.


title: Protein folding

text: Several large-scale computational projects, such as Rosetta@home, Folding@home and Foldit, target protein folding.


title: Protein folding

text: Long continuous-trajectory simulations have been performed on Anton, a massively parallel supercomputer designed and built around custom ASICs and interconnects by D. E. Shaw Research. The longest published result of a simulation performed using Anton is a 2.936 millisecond simulation of NTL9 at 355 K.


title: Victor Hugo (artist and window dresser)

text: Victor Hugo, born Victor Rojas, (1948–1994) was a Venezuelan-born American artist, window dresser, and partner of the designer Halston.


title: Victor Hugo (artist and window dresser)

text: Robb Hernandez wrote in 2019 that Hugo was born at the time of a military coup d'état in Caracas and emigrated with his mother to New York City around 1973.


title: Victor Hugo (artist and window dresser)

text: Hugo first encountered Halston while working as an escort to make ends meet as a student. Upon their relationship progressing from transactional to romantic, Hugo began doing displays for Halston's Madison Avenue store and later became one of Andy Warhol's assistants at The Factory where among other things he worked on the painter's oxidation paintings. He is said to have been the first window dresser to have incorporated Pop art into his designs. He was also a model for Warhol's "Torso" and "Sex Parts" series. In keeping with his energetic persona, Hugo was quoted in "Interview Magazine" (April 1975): “Perhaps you would describe me as jaded, darling, but I prefer to say that in living there is absolutely nothing that is bad. I can only say that I live fully 24 hours a day—and I regret nothing".


title: Victor Hugo (artist and window dresser)

text: When Studio 54 opened in 1977, Halston and Hugo immersed themselves in a hedonistic and partying lifestyle. Cocaine infused orgies were held at Halston's Upper East Side townhome with Warhol photographing the happenings from the sidelines. In his memoir, Bob Colacello described how Warhol often used Hugo to antagonize Halston: “Andy loved it when Victor showed up at [Studio] 54 in a jockstrap or at a Halston party in a Halston dress, in both cases much to Halston’s embarrassment...Victor later told me that Andy actually "paid" him to do these things”. He further stated that "Andy saw Victor as the perfect source for ideas: someone with a fertile imagination who didn't know what to do with it...The Venezuelan's own art was going nowhere: He signed rat traps and handed them out at parties; he dipped chickens' feet in red paint and called their footprints drawings". In 1978, the artist and videographer Anton Perich made a short film of Hugo destroying a Warhol painting as "a sacrifice".


title: Victor Hugo (artist and window dresser)

text: His intermittent relationship with Halston dissipated after about seventeen years. As Miller (2021) described, Hugo's ever-increasing drug addiction and tempestuous nature was a contributing factor to the couple's breakup. Hugo reportedly stole Warhol's works and Elsa Peretti's belongings to feed his drug habit. By 1988, Halston had been diagnosed with HIV and relocated soon after to San Francisco to be closer to his family. Despite their relationship having ended, Halston still continued to pay for Hugo's housing and other expenses. In 1989, Hugo had expressed dissatisfaction with how he was portrayed in "The Andy Warhol Diaries—"threatening to auction off any Warhol piece in his possession: "I feel like the Central Park jogger...I've been gang-raped and beaten by a dead person and bunch of thugs that work for him. It is the most vile, disgusting piece of pulp literature I have ever read..." Shortly before Halston's death in 1990, a contract was drawn up requiring that Hugo would not contest Halston's will nor cause any embarrassment to the estate. As Stein noted (2021), Hugo had signed a nondisclosure agreement in 1985 to not speak publicly about his relationship with Halston in return for a large monetary sum and some Warhol pieces. Bob Halston locked Hugo out of Halston's New York property after learning that Hugo had moved back in and was taking Halston's personal property.


title: Victor Hugo (artist and window dresser)

text: It was reported in 1993 that Hugo was working on an autobiography, though the project never came to fruition. In his 1997 book "The Last Party: Studio 54, Disco, and the Culture of the Night", Anthony Haden-Guest wrote how the artist Scott Covert encountered a homeless Hugo in December 1993 sleeping in a park after running out of money to stay at the Hotel Chelsea. Covert and fellow Hotel Chelsea resident Colleen Weinstein helped a cancer-stricken Hugo such as taking him to his hospital visits. When Hugo died in 1994 from AIDS-related complications, Covert and Weinstein did not have the funds to bury him and it took them two weeks to save up enough money. They buried him on Halston's birthday at an East Hampton cemetery.


title: Victor Hugo (artist and window dresser)

text: In September 2007, an exhibition of mannequins dressed by Hugo (from Warhol's collection) was held at the Milk Gallery in New York City. In 2010, Juliana Cairone used Hugo as an inspiration when creating a display to showcase her Halston clothing for sale. Hugo was featured in archive footage about his relationship with the designer in the 2019 documentary film "Halston". Among the interviewees was Sassy Johnson, and she gave the following assessment about Halston's relationship with Hugo: "My theory has always been that Halston came from an alcoholic family, that his father had a problem...[and] that Halston recreated his family life with Victor as the dysfunctional person who is constantly going to keep everything off balance". Gian Franco Rodríguez portrays Hugo in the 2021 Ryan Murphy produced Netflix television miniseries "Halston". To prepare for the role, Rodriguez conducted extensive research that included consulting with one of Hugo's friends.


title: Spencer Dinwiddie

text: Spencer Gray Dinwiddie (born April 6, 1993) is an American professional basketball player for the Dallas Mavericks of the National Basketball Association (NBA). He played college basketball for the Colorado Buffaloes and earned first-team all-conference honors in the Pac-12 as a sophomore in 2013. He missed most of his junior year after injuring his anterior cruciate ligament (ACL). Dinwiddie recovered and was selected by the Detroit Pistons in the second round of the 2014 NBA draft. After two seasons with the Pistons, he joined the Brooklyn Nets in December 2016 and played with them until being traded to the Washington Wizards in 2021. In February 2022, Dinwiddie was traded to the Dallas Mavericks.


title: Spencer Dinwiddie

text: At William Howard Taft High School, Dinwiddie was recognized as one of the greatest standout athletes since Jordan Farmar. He averaged 5.9 points and 4.1 assists as the starting point guard alongside a fellow 2014 draftee in DeAndre Daniels at the conclusion of his junior season. Dinwiddie maximized his game as he began his final year representing the school, averaging 11.2 points and 7.7 assists. He was one of the most skilled passers in school history, and became the John R. Wooden California High School Player of the Year in 2011. However, Long Beach Poly's Ryan Anderson was named California Mr. Basketball. Dinwiddie became just one of seven players that won the prestigious award as a senior. The powerful duo of Daniels and Dinwiddie won the city championship this season as well. This final season at Taft helped Dinwiddie gain the attention of colleges around the country. He chose to attend Colorado rather than Harvard, Oregon, Santa Clara, or UNLV.


title: Spencer Dinwiddie

text: Considered a three-star recruit by Rivals.com, Dinwiddie was listed as the No. 25-point guard and the No. 146 player in the nation in 2011.


title: Spencer Dinwiddie

text: In the first regular season game for Colorado, Dinwiddie made his collegiate debut in a 32-point victory over Fort Lewis with seven points and seven rebounds. He shot just 2-for-9 from the field. Dinwiddie reached double figures in his sixth appearance, which was against Georgia. This was the first time he had shot over .500 on field goals up till then. The California native led the team to this win and made three key free throws in the final seconds. Dinwiddie teamed with fellow freshman Askia Booker, forming another duo on his new team. They combined for 677 points, making school history by scoring over 250 points each. At the conclusion of the season, they were the only Buffaloes to do so. Dinwiddie became a member of the Pac-12 Conference Tournament Championship Team. He led Colorado in free throw percentage and ranked third among freshmen in that category. By the end of the regular season, Dinwiddie had helped the team earn its first NCAA men's basketball tournament berth since the 2002–03 season. Shooting three-pointers at .438 clip, Dinwiddie was named to the Pac-12 All-Freshman Team with Tony Wroten. He was the only Pac-12 freshman to have a field-goal percentage of over .400 total.


title: Spencer Dinwiddie

text: The departures of Carlon Brown and Nate Tomlinson were instrumental in Dinwiddie's breakout sophomore season, when he earned first-team All-Pac-12 honors. Leading the team in assists, they reached the NCAA men's basketball tournament for the second consecutive season, in which they reached the second round. It was the first time the team had reached back-to-back tournaments since the 1963 season. The Buffaloes won the 2012 Charleston Classic, in which Dinwiddie took the role as starting small forward in the final three rounds. He was just one of two players – the other being Askia Booker – to start all 33 games. By the end of the season, Booker and Dinwiddie became the highest sophomore scoring tandem in school history. Dinwiddie led the team in assists 20 times and was the top scorer on 15 different occasions. He recorded 29 points in a home win over Colorado State, which marked his own career-high scoring record. On February 10, 2012, Dinwiddie recorded a perfect game against Oregon State. He shot 6-for-6 from the field, 4-for-4 from beyond the arc, and 8-for-8 on free throws. This set the school record for most points scored without missing a single shot. He made the remark, "I see over people and I shoot over people... for the smaller point guards, they don't really get to contest me." The Taft graduate stood by the end of the season.


title: Spencer Dinwiddie

text: Dinwiddie continued to act as the leader of the Colorado Buffaloes men's basketball team through the beginning of his junior year. He helped the team win 14 of their first 16 regular season games, which made them one of the most successful underdogs in the country, most notably toppling the Kansas Jayhawks due to a game-winner from Askia Booker. Dinwiddie was considered the catalyst for the unanticipated run from his team, however. On November 21, 2012, he shot a career-best 14-for-15 from the free throw line against Santa Barbara. Colorado won each game in which their top scorer scored 20 or more points total.


title: Spencer Dinwiddie

text: On January 12, 2014, Dinwiddie suffered a career-threatening ACL injury against Washington, forcing him to sit out for the remainder of the season. As his junior season was cut short, the team finished the year just 23–12; their record was 14–2 while Dinwiddie was healthy. Dinwiddie reportedly made contact with Russ Paine, who helped Adrian Peterson recover from his ACL injury and become the 2012 NFL MVP.


title: Spencer Dinwiddie

text: On April 24, 2014, Dinwiddie declared for the NBA draft, foregoing his final year of college eligibility.


title: Spencer Dinwiddie

text: Dinwiddie was selected with the 38th overall pick by the Detroit Pistons in the 2014 NBA draft. He appeared in 34 games for the Pistons as a rookie, making one start and receiving two assignments to the Grand Rapids Drive, the Pistons' D-League affiliate. His lone start came on February 20, 2015, after a pair of trades left the Pistons short-handed. He had career highs of 12 points and nine assists in a 100–91 win over the Chicago Bulls. Eight days later, he scored a season-best 20 points to go with eight assists in 25 minutes off the bench in a 99–95 loss to the Washington Wizards.


title: Spencer Dinwiddie

text: The 2015–16 season saw Dinwiddie appear in just 12 regular-season games for the Pistons, after spending the majority of the season in the D-League with the Grand Rapids Drive. After back-up Steve Blake opened the season in a miserable shooting slump, Dinwiddie received his first opportunity of the season in the tenth game, scoring 17 points on November 15 in a 97–85 loss to the Los Angeles Lakers. However, after struggling in the next four games, he fell out of the rotation, compounded by Blake's form improvement and Brandon Jennings returning from injury. Dinwiddie played a season-high 29 minutes in the Pistons' regular-season finale on April 13, scoring 12 points in a 112–110 overtime win over the Cleveland Cavaliers. He then appeared in game two of the Pistons' 4–0 first-round playoff series loss to the Cavaliers.


title: Spencer Dinwiddie

text: On June 17, 2016, Dinwiddie was traded to the Chicago Bulls in exchange for Cameron Bairstow. He was waived by the Bulls on July 7, re-signed on July 28, and waived again on October 21 after appearing in five preseason games. He then spent the start of the 2016–17 season with Chicago's D-League affiliate team, the Windy City Bulls, averaging 19.4 points, 8.1 assists and 3.7 rebounds over 37.4 minutes in nine games.


title: Spencer Dinwiddie

text: On December 8, 2016, Dinwiddie signed with the Brooklyn Nets. On February 15, 2017, he scored 15 of his season-high 19 points in the fourth quarter of the Nets' 129–125 loss to the Milwaukee Bucks. On April 8, 2017, in a 107–106 win over the Chicago Bulls, Dinwiddie made four free throws in the final 13.6 seconds and finished with 19 points.


title: Spencer Dinwiddie

text: On October 25, 2017, Dinwiddie scored a career-high 22 points and hit the go-ahead 3-pointer with 43 seconds left to lift the Nets to a 112–107 win over the Cleveland Cavaliers. On October 29, he tied his career high with 22 points in a 124–111 loss to the Denver Nuggets. On November 17, he set a new career high with 25 points in a 118–107 win over the Utah Jazz. On December 14, he had 26 points in a 111–104 loss to the New York Knicks. On December 23, he tied his career high with 26 points in a 123–119 overtime loss to the Indiana Pacers. On January 3, 2018, he made the go-ahead jumper with 10.1 seconds left and tied his career high with 26 points, leading Brooklyn to a 98–97 victory over the Minnesota Timberwolves. On January 8, he set a new career high with 31 points in a 114–113 overtime loss to the Toronto Raptors. On January 12, he recorded a near triple-double with 20 points, 10 assists and nine rebounds in a 110–105 win over the Atlanta Hawks. On January 17, he had a career-high 13 assists in a 100–95 loss to the San Antonio Spurs. On February 17, Dinwiddie won the Skills Challenge at All-Star Weekend.


title: Spencer Dinwiddie

text: On November 25, 2018, Dinwiddie scored 31 points in a 127–125 loss to the Philadelphia 76ers. On December 12, he scored a career-high 39 points in a 127–124 win over the 76ers. On December 13, he signed a reported three-year, $34 million contract extension with the Nets. On December 26, he had 37 points and 11 assists off the bench in a 134–132 double-overtime win over the Charlotte Hornets. It was his third 30-point game off the bench, matching the franchise record set by Clifford T. Robinson in 1980–81. On January 16, 2019, he scored 25 of his 33 points in the fourth quarter and overtime of the Nets' 145–142 win over the Houston Rockets. On January 23, he scored a game-high 29 points in a 114–110 win over the Orlando Magic, thus scoring at least 25 points off the bench in 10 games, matching a franchise single-season record—Bubbles Hawkins set the mark during the Nets' inaugural NBA season in 1976–77. Two days later, it was revealed that a right thumb injury that he had originally hurt roughly two months earlier and had gotten progressively worse would require surgery, having suffered torn ligaments. He underwent surgery on January 28. He returned to action on March 1 after missing 14 games, scoring 15 points off the bench in a 123–112 loss to the Hornets. With 28 points against the Cavaliers on March 6, Dinwiddie had his 14th 20-point game off the bench to set a Nets single-season record—Darryl Dawkins, Purvis Short and Orlando Woolridge all had 13. With 23 points against the Hawks on March 9, Dinwiddie surpassed Armen Gilliam in 1993–94 with the most single-season points in a reserve role.


title: Spencer Dinwiddie

text: During the 2019–20 NBA season, Dinwiddie began the season as a reserve until Kyrie Irving injured his shoulder. On January 28, 2020, Dinwiddie switched his jersey number from 8 to 26 after the approval of the NBA, in honor of the late Kobe Bryant. On June 29, 2020, Dinwiddie announced that he had tested positive for COVID-19.


title: Spencer Dinwiddie

text: On December 27, 2020, Dinwiddie left the game between the Nets and the Charlotte Hornets with a suspected right knee strain, which was later revealed to be a season-ending partial ACL tear.


title: Spencer Dinwiddie

text: On August 6, 2021, Dinwiddie was acquired by the Washington Wizards via a sign-and-trade deal involving five teams, sending Russell Westbrook to the Los Angeles Lakers. Dinwiddie signed a three-year deal worth $54 million and a maximum of $60 million through incentives.


title: Spencer Dinwiddie

text: On February 10, 2022, Dinwiddie was traded, along with Dāvis Bertāns, to the Dallas Mavericks in exchange for Kristaps Porziņģis and a protected 2022 second-round pick. On March 5, Dinwiddie scored a season-high 36 points against the Sacramento Kings. On April 16, during Game 1 of the first round of the playoffs, he logged 22 points and eight assists in a 93–99 loss to the Utah Jazz.


title: Spencer Dinwiddie

text: In 2013, Dinwiddie was named to the USA Basketball Men's World University Games Team for the 2013 Summer Universiade in Kazan, Russia. He was one of three players on Team USA to start all eight games. He averaged 7.9 points and 2.6 rebounds per game and led Team USA with 44 assists (5.5 apg) and with 12 steals (1.5 spg).


title: Spencer Dinwiddie

text: Dinwiddie is the son of Malcolm and Stephanie Dinwiddie, and he has a younger brother, Taylor. Dinwiddie has a son with girlfriend Arielle Roberson, the sister of fellow NBA player André Roberson.


title: Big band

text: A big band or jazz orchestra is a type of musical ensemble of jazz music that usually consists of ten or more musicians with four sections: saxophones, trumpets, trombones, and a rhythm section. Big bands originated during the early 1910s and dominated jazz in the early 1940s when swing was most popular. The term "big band" is also used to describe a genre of music, although this was not the only style of music played by big bands.


title: Big band

text: Big bands started as accompaniment for dancing. In contrast to the typical jazz emphasis on improvisation, big bands relied on written compositions and arrangements. They gave a greater role to bandleaders, arrangers, and sections of instruments rather than soloists.


title: Big band

text: Big bands generally have four sections: trumpets, trombones, saxophones, and a rhythm section of guitar, piano, double bass, and drums. The division in early big bands, from the 1920s to 1930s, was typically two or three trumpets, one or two trombones, three or four saxophones, and a rhythm section of four instruments. In the 1940s, Stan Kenton's band used up to five trumpets, five trombones (three tenor and two bass trombones), five saxophones (two alto saxophones, two tenor saxophones, one baritone saxophone), and a rhythm section. Duke Ellington at one time used six trumpets. While most big bands dropped the previously common jazz clarinet from their arrangements (other than the clarinet-led orchestras of Artie Shaw and Benny Goodman), many Duke Ellington songs had clarinet parts, often replacing or doubling one of the tenor saxophone parts; more rarely, Ellington would substitute baritone sax for bass clarinet, such as in "Ase's Death" from Swinging Suites. Boyd Raeburn drew from symphony orchestras by adding flute, French horn, strings, and timpani to his band.


title: Big band

text: Jazz ensembles numbering eight (octet), nine (nonet) or ten (tentet) voices are sometimes called "little big bands".


title: Big band

text: Twenty-first century big bands can be considerably larger than their predecessors, exceeding 20 players, with some European bands using 29 instruments and some reaching 50.


title: Big band

text: It is useful to distinguish between the roles of composer, arranger and leader. The composer writes original music that will be performed by individuals or groups of various sizes, while the arranger adapts the work of composers in a creative way for a performance or recording. Arrangers frequently notate all or most of the score of a given number, usually referred to as a "chart". Bandleaders are typically performers who assemble musicians to form an ensemble of various sizes, select or create material for them, shape the music’s dynamics, phrasing, and expression in rehearsals, and lead the group in performance often while playing alongside them. Some bandleaders, such as Guy Lombardo, performed works composed by others (in Lombardo's case, often by his brother Carmen), while others, such as Maria Schneider, take on all three roles. In many cases, however, the distinction between these roles can become blurred. Billy Strayhorn, for example, was a prolific composer and arranger, frequently collaborating with Duke Ellington, but rarely took on the role of bandleader, which was assumed by Ellington, who himself was a composer and arranger.


title: Big band

text: Typical big band arrangements from the swing era were written in strophic form with the same phrase and chord structure repeated several times. Each iteration, or chorus, commonly follows twelve bar blues form or thirty-two-bar (AABA) song form. The first chorus of an arrangement introduces the melody and is followed by choruses of development. This development may take the form of improvised solos, written solo sections, and "shout choruses".


title: Big band

text: An arrangement's first chorus is sometimes preceded by an introduction, which may be as short as a few measures or may extend to a chorus of its own. Many arrangements contain an interlude, often similar in content to the introduction, inserted between some or all choruses. Other methods of embellishing the form include modulations and cadential extensions.


title: Big band

text: Some big ensembles, like King Oliver's, played music that was half-arranged, half-improvised, often relying on head arrangements. A head arrangement is a piece of music that is formed by band members during rehearsal. They experiment, often with one player coming up with a simple musical figure leading to development within the same section and then further expansion by other sections, with the entire band then memorizing the way they are going to perform the piece, without writing it on sheet music. During the 1930s, Count Basie's band often used head arrangements, as Basie said, "we just sort of start it off and the others fall in." Head arrangements were more common during the period of the 1930s because there was less turnover in personnel, giving the band members more time to rehearse.


title: Big band

text: Before 1910, social dance in America was dominated by steps such as the waltz and polka. As jazz migrated from its New Orleans origin to Chicago and New York City, energetic, suggestive dances traveled with it. During the next decades, ballrooms filled with people doing the jitterbug and Lindy Hop. The dance duo Vernon and Irene Castle popularized the foxtrot while accompanied by the Europe Society Orchestra led by James Reese Europe.


title: Big band

text: One of the first bands to accompany the new rhythms was led by a drummer, Art Hickman, in San Francisco in 1916. Hickman's arranger, Ferde Grofé, wrote arrangements in which he divided the jazz orchestra into sections that combined in various ways. This intermingling of sections became a defining characteristic of big bands. In 1919, Paul Whiteman hired Grofé to use similar techniques for his band. Whiteman was educated in classical music, and he called his new band's music symphonic jazz. The methods of dance bands marked a step away from New Orleans jazz. With the exception of Jelly Roll Morton, who continued playing in the New Orleans style, bandleaders paid attention to the demand for dance music and created their own big bands. They incorporated elements of Broadway, Tin Pan Alley, ragtime, and vaudeville.


title: Big band

text: Duke Ellington led his band at the Cotton Club in Harlem. Fletcher Henderson's career started when he was persuaded to audition for a job at Club Alabam in New York City, which eventually turned into a job as bandleader at the Roseland Ballroom. At these venues, which themselves gained notoriety, bandleaders and arrangers played a greater role than they had before. Hickman relied on Ferde Grofé, Whiteman on Bill Challis. Henderson and arranger Don Redman followed the template of King Oliver, but as the 1920s progressed they moved away from the New Orleans format and transformed jazz. They were assisted by a band full of talent: Coleman Hawkins on tenor saxophone, Louis Armstrong on cornet, and multi-instrumentalist Benny Carter, whose career lasted into the 1990s.


title: Big band

text: Swing music began appearing in the early 1930s and was distinguished by a more supple feel than the more literal of early jazz. Walter Page is often credited with developing the walking bass, though earlier examples exist, such as Wellman Braud on Ellington's "Washington Wabble" from 1927.


title: Big band

text: This type of music flourished through the early 1930s, although there was little mass audience for it until around 1936. Up until that time, it was viewed with ridicule and looked upon as a curiosity. After 1935, big bands rose to prominence playing swing music and held a major role in defining swing as a distinctive style. Western swing musicians also formed popular big bands during the same period.


title: Big band

text: There was a considerable range of styles among the hundreds of popular bands. Many of the better known bands reflected the individuality of the bandleader, the lead arranger, and the personnel. Count Basie played a relaxed, propulsive swing, Bob Crosby (brother of Bing), more of a dixieland style, Benny Goodman a hard driving swing, and Duke Ellington's compositions were varied and sophisticated. Many bands featured strong instrumentalists whose sounds dominated, such as the clarinets of Benny Goodman and Artie Shaw, the trombone of Jack Teagarden, the trumpet of Harry James, the drums of Gene Krupa, and the vibes of Lionel Hampton. The popularity of many of the major bands was amplified by star vocalists, such as Frank Sinatra with Tommy Dorsey, Helen O'Connell and Bob Eberly with Jimmy Dorsey, Ella Fitzgerald with Chick Webb, Billie Holiday and Jimmy Rushing with Count Basie, Dick Haymes and Helen Forrest with Harry James, Doris Day with Les Brown, and Peggy Lee with Benny Goodman. Some bands were "society bands" which relied on strong ensembles but little on soloists or vocalists, such as the bands of Guy Lombardo and Paul Whiteman.


title: Big band

text: A distinction is often made between so-called "hard bands", such as those of Count Basie and Tommy Dorsey, which emphasized quick hard-driving jump tunes, and "sweet bands", such as the Glenn Miller Orchestra and the Shep Fields Rippling Rhythm Orchestra. who specialized in less improvised tunes with more emphasis on sentimentality, featuring somewhat slower-paced, often heart-felt songs.


title: Big band

text: By this time the big band was such a dominant force in jazz that the older generation found they either had to adapt to it or simply retire. With no market for small-group recordings (made worse by a Depression-era industry reluctant to take risks), musicians such as Louis Armstrong and Earl Hines led their own bands, while others, like Jelly Roll Morton and King Oliver, lapsed into obscurity.


title: Big band

text: The major "black" bands of the 1930s included, apart from Ellington's, Hines's and Calloway's, those of Jimmie Lunceford, Chick Webb, and Count Basie. The "white" bands of Benny Goodman, Artie Shaw, Tommy Dorsey, Shep Fields and, later, Glenn Miller were more popular than their "black" counterparts from the middle of the decade. Bridging the gap to white audiences in the mid-1930s was the Casa Loma Orchestra and Benny Goodman's early band.


title: Big band

text: White teenagers and young adults were the principal fans of the big bands in the late 1930s and early 1940s. They danced to recordings and the radio and attended live concerts. They were knowledgeable and often biased toward their favorite bands and songs, and sometimes worshipful of famous soloists and vocalists. Many bands toured the country in grueling one-night stands. Traveling conditions and lodging were difficult, in part due to segregation in most parts of the United States, and the personnel often had to perform having had little sleep and food. Apart from the star soloists, many musicians received low wages and would abandon the tour if bookings disappeared. Sometimes bandstands were too small, public address systems inadequate, pianos out of tune. Bandleaders dealt with these obstacles through rigid discipline (Glenn Miller) and canny psychology (Duke Ellington).


title: Big band

text: Big bands uplifted morale during World War II. Many musicians served in the military and toured with USO troupes at the front, with Glenn Miller losing his life while traveling between shows. Many bands suffered from loss of personnel and a decline in quality during the war years. The 1942–44 musicians' strike worsened the situation. Vocalists began to strike out on their own. By the end of the war, swing was giving way to less danceable music, such as bebop. Many of the great swing bands broke up, as the times and tastes changed.


title: Big band

text: Many bands from the swing era continued for decades after the death or departure of their founders and namesakes, and some are still active in the 21st century, often referred to as "ghost bands", a term attributed to Woody Herman, referring to orchestras that persist in the absence of their original leaders.


title: Big band

text: Although big bands are identified with the swing era, they continued to exist after those decades, though the music they played was often different from swing. Bandleader Charlie Barnet's recording of "Cherokee" in 1942 and "The Moose" in 1943 have been called the beginning of the bop era. Woody Herman's first band, nicknamed the First Herd, borrowed from progressive jazz, while the Second Herd emphasized the saxophone section of three tenors and one baritone. In the 1950s, Stan Kenton referred to his band's music as "progressive jazz", "modern", and "new music". He created his band as a vehicle for his compositions. Kenton pushed the boundaries of big bands by combining clashing elements and by hiring arrangers whose ideas about music conflicted. This expansive eclecticism characterized much of jazz after World War II. During the 1960s and '70s, Sun Ra and his Arketstra took big bands further out. Ra's eclectic music was played by a roster of musicians from ten to thirty and was presented as theater, with costumes, dancers, and special effects.


title: Big band

text: As jazz was expanded during the 1950s through the 1970s, the Basie and Ellington bands were still around, as were bands led by Buddy Rich, Gene Krupa, Lionel Hampton, Earl Hines, Les Brown, Clark Terry, and Doc Severinsen. Progressive bands were led by Dizzy Gillespie, Gil Evans, Carla Bley, Toshiko Akiyoshi and Lew Tabackin, Don Ellis, and Anthony Braxton.


title: Big band

text: In the 1960s and 1970s, big band rock became popular by integrating such musical ingredients as progressive rock experimentation, jazz fusion, and the horn choirs often used in blues and soul music, with some of the most prominent groups including Chicago; Blood, Sweat and Tears; Tower of Power; and, from Canada, Lighthouse. The genre was gradually absorbed into mainstream pop rock and the jazz rock sector.


title: Big band

text: Other bandleaders used Brazilian and Afro-Cuban music with big band instrumentation, and big bands led by arranger Gil Evans, saxophonist John Coltrane (on the album "Ascension" from 1965) and bass guitarist Jaco Pastorius introduced cool jazz, free jazz and jazz fusion, respectively, to the big band domain. Modern big bands can be found playing all styles of jazz music. Some large contemporary European jazz ensembles play mostly avant-garde jazz using the instrumentation of the big bands. Examples include the Vienna Art Orchestra, founded in 1977, and the Italian Instabile Orchestra, active in the 1990s.


title: Big band

text: In the late 1990s, there was a swing revival in the U.S. The Lindy Hop became popular again and young people took an interest in big band styles again.


title: Big band

text: Big bands maintained a presence on American television, particularly through the late-night talk show, which has historically used big bands as house accompaniment. Typically the most prominent shows with the earliest time slots and largest audiences have bigger bands with horn sections while those in later time slots go with smaller, leaner ensembles.


title: Big band

text: Many college and university music departments offer jazz programs and feature big band courses in improvisation, composition, arranging, and studio recording, featuring performances by 18 to 20 piece big bands.


title: Big band

text: During the 1930s, Earl Hines and his band broadcast from the Grand Terrace in Chicago every night across America. In Kansas City and across the Southwest, an earthier, bluesier style was developed by such bandleaders as Bennie Moten and, later, by Jay McShann and Jesse Stone. By 1937, the "sweet jazz band" saxophonist Shep Fields was also featured over the airways on the NBC radio network in his "Rippling Rhythm Revue," which also showcased a young Bob Hope as the announcer. Big band remotes on the major radio networks spread the music from ballrooms and clubs across the country during the 1930s and 1940s, with remote broadcasts from jazz clubs continuing into the 1950s on NBC's "Monitor". Radio increased the fame of Benny Goodman, the "Pied Piper of Swing". Others challenged him, and battle of the bands became a regular feature of theater performances.


title: Big band

text: Gloria Parker had a radio program on which she conducted the largest all-girl orchestra led by a female. She led her Swingphony while playing marimba. Phil Spitalny, a native of Ukraine, led a 22-piece female orchestra known as Phil Spitalny and His Hour of Charm Orchestra, named for his radio show, "The Hour of Charm", during the 1930s and 1940s. Other female bands were led by trumpeter B. A. Rolfe, Anna Mae Winburn, and Ina Ray Hutton.


title: Big band

text: Big Bands began to appear in movies in the 1930s through the 1960s, though cameos by bandleaders were often stiff and incidental to the plot. Fictionalized biographical films of Glenn Miller, Gene Krupa, and Benny Goodman were made in the 1950s.


title: Big band

text: The bands led by Helen Lewis, Ben Bernie, and Roger Wolfe Kahn's band were filmed by Lee de Forest in his Phonofilm sound-on-film process in 1925, in three short films which are in the Library of Congress film collection.


title: Sphagnum

text: Sphagnum is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, peat moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of "Sphagnum" can store water, since both living and dead plants can hold large quantities of water inside their cells; plants may hold 16 to 26 times as much water as their dry weight, depending on the species. The empty cells help retain water in drier conditions.


title: Sphagnum

text: As sphagnum moss grows, it can slowly spread into drier conditions, forming larger mires, both raised bogs and blanket bogs. Thus, sphagnum can influence the composition of such habitats, with some describing sphagnum as 'habitat manipulators'. These peat accumulations then provide habitat for a wide array of peatland plants, including sedges and ericaceous shrubs, as well as orchids and carnivorous plants.


title: Sphagnum

text: "Sphagnum" and the peat formed from it do not decay readily because of the phenolic compounds embedded in the moss's cell walls. In addition, bogs, like all wetlands, develop anaerobic soil conditions, which produces slower anaerobic decay rather than aerobic microbial action. Peat moss can also acidify its surroundings by taking up cations, such as calcium and magnesium, and releasing hydrogen ions.


title: Sphagnum

text: Under the right conditions, peat can accumulate to a depth of many meters. Different species of "Sphagnum" have different tolerance limits for flooding and pH, so any one peatland may have a number of different "Sphagnum" species.


title: Sphagnum

text: Individual peat moss plants consist of a main stem, with tightly arranged clusters of branch fascicles usually consisting of two or three spreading branches and two to four hanging branches. The top of the plant, or capitulum, has compact clusters of young branches. Along the stem are scattered leaves of various shapes, named stem leaves; the shape varies according to species. The leaves consist of two kinds of cells: small, green, living cells (chlorophyllose cells), and large, clear, structural, dead cells (hyaline cells). The latter have the large water-holding capacity.


title: Sphagnum

text: "Sphagnum" have a distinct structure adapted to the watery habitats they live in. The water supports Sphagnum plants, making other strengthening structures unnecessary. The top of the plant is called the capitulum, a rosette of leaves which gather the majority of the plant's energy through photosynthesis. The main body consists of a stem and branches, with leaves also protruding from both the stem and the branches. The lowermost parts of the plant are dead but partially decomposed.


title: Sphagnum

text: "Sphagnum" has a distinctive cellular structure. Mosses have no vascular system to move water and nutrients around the plant. Thus tissues are thin and usually one cell thick to allow these to diffuse easily. "Sphagnum" mosses have two distinct cell types. There are normal photosynthesising cells with chlorophyll. Additionally there are larger Aline or retort cells. These are barrel shaped. They have pores and soak up water like a sponge. These unique cells mean "Sphagnum" can keep the habitat watery by releasing water to keep bogs waterlogged. Walker (2019) describes "Sphagnum" thus as 'habitat manipulators'.


title: Sphagnum

text: "Sphagnum", like all other land plants, has an alternation of generations; like other bryophytes, the haploid gametophyte generation is dominant and persistent. Unlike other mosses, the long-lived gametophytes do not rely upon rhizoids to assist in water uptake.


title: Sphagnum

text: "Sphagnum" species can be unisexual (male or female, dioecious) or bisexual (male and female gametes produced from the same plant; monoecious); In North America, 80% of "Sphagnum" species are unisexual.


title: Sphagnum

text: Gametophytes have substantial asexual reproduction by fragmentation, producing much of the living material in sphagnum peatlands.


title: Sphagnum

text: Swimming sperm fertilize eggs contained in archegonia that remain attached to the female gametophyte. The sporophyte is relatively short-lived, and consists almost entirely of a shiny green, spherical spore capsule that becomes black with spores. Sporophytes are raised on stalks to facilitate spore dispersal, but unlike other mosses, "Sphagnum" stalks are produced by the maternal gametophyte. Tetrahedral haploid spores are produced in the sporophyte by meiosis, which are then dispersed when the capsule explosively discharges its cap, called an operculum, and shoots the spores some distance. The spores germinate to produce minute protonemae, which start as filaments, can become thalloid, and can produce a few rhizoids. Soon afterwards, the protonema develops buds and these differentiate into its characteristic, erect, leafy, branched gametophyte with chlorophyllose cells and hyaline cells. This stage dominates the environment where "Sphagnum" grows, obliterating and burying the protonema and eventually building up into layers of dead moss called peat.


title: Sphagnum

text: Carpets of living "Sphagnum" may be attacked by various fungi, and one fungus that is also a mushroom, "Sphagnurus paluster", produces conspicuous dead patches. When this fungus and other agarics attack the protonema, "Sphagnum" is induced to produce nonphotosynthetic gemmae that can survive the fungal attack and months later germinate to produce new protonema and leafy gametophytes. It is unknown whether the leafy stage can produce such gemmae.


title: Sphagnum

text: Peat moss can be distinguished from other moss species by its unique branch clusters. The plant and stem color, the shape of the branch and stem leaves, and the shape of the green cells are all characteristics used to identify peat moss to species. "Sphagnum" taxonomy has been very contentious since the early 1900s; most species require microscopic dissection to be identified. In the field, most "Sphagnum" species can be identified to one of four major sections of the genus—classification and descriptions follow Andrus 2007 (Flora North America):


title: Sphagnum

text: The reciprocal monophyly of these sections and two other minor ones ("Rigida" and "Squarrosa") has been clarified using molecular phylogenetics. All but two species normally identified as "Sphagnum" reside in one clade; two other species have recently been separated into new families within the Sphagnales reflecting an ancestral relationship with the Tasmanian endemic "Ambuchanania" and long phylogenetic distance to the rest of "Sphagnum". Within main clade of "Sphagnum", phylogenetic distance is relatively short, and molecular dating methods suggest nearly all current "Sphagnum" species are descended from a radiation that occurred just 14 million years ago.


title: Sphagnum

text: "Sphagnum" mosses occur mainly in the Northern Hemisphere in peat bogs, conifer forests, and moist tundra areas. Their northernmost populations lie in the archipelago of Svalbard, Arctic Norway, at 81° N.


title: Sphagnum

text: In the Southern Hemisphere, the largest peat areas are in southern Chile and Argentina, part of the vast Magellanic moorland ("circa" 44,000 square km; 17,000 sq. mi.). Peat areas are also found in New Zealand and Tasmania. In the Southern Hemisphere, however, peat landscapes may contain many moss species other than "Sphagnum". "Sphagnum" species are also reported from "dripping rocks" in mountainous, subtropical Brazil.


title: Sphagnum

text: As with many other mosses, "Sphagnum" species disperse spores through the wind. The tops of spore capsules are only about 1 cm (") above ground, and where wind is weak. As the spherical spore capsule dries, the operculum is forced off, followed by a cloud of spores. The exact mechanism has traditionally attributed to a "pop gun" method using air compressed in the capsule, reaching a maximum velocity of 3.6 meters (12') per second, but alternative mechanisms have been recently proposed. High-speed photography has shown vortex rings are created during the discharge, which enable the spores to reach a height of 10 to 20 cm (4" to 8"), further than would be expected by ballistics alone. The acceleration of the spores is about 36,000G. Spores are extremely important in establishment of new populations in disturbed habitats and on islands.


title: Sphagnum

text: Human activities like slash-and-burn and cattle grazing are believed to promote the growth and expansion of Sphagnum moss. Oceanic islands such as the Faroe Islands, the Galápagos or the Azores have recorded a significant increase in their Sphagnum populations after human settlement.


title: Sphagnum

text: Decayed, dried sphagnum moss has the name of peat or peat moss. This is used as a soil conditioner which increases the soil's capacity to hold water and nutrients by increasing capillary forces and cation exchange capacity – uses that are particularly useful in gardening. This is often desired when dealing with very sandy soil, or plants that need increased or steady moisture content to flourish. A distinction is sometimes made between sphagnum moss, the live moss growing on top of a peat bog, and 'sphagnum peat moss' (North American usage) or 'sphagnum peat' (British usage), the latter being the slowly decaying matter underneath.


title: Sphagnum

text: Anaerobic acidic sphagnum bogs have low rates of decay, and hence preserve plant fragments and pollen to allow reconstruction of past environments. They even preserve human bodies for millennia; examples of these preserved specimens are Tollund Man, Haraldskær Woman, Clonycavan Man and Lindow Man. Such bogs can also preserve human hair and clothing, one of the most noteworthy examples being Egtved Girl, Denmark. Because of the acidity of peat, however, bones are dissolved rather than preserved. These bogs have also been used to preserve food. Up to 2000-year-old containers of butter or lard have been found.


title: Sphagnum

text: "Sphagnum" moss has been used for centuries as a dressing for wounds, including through World War I. Preparations using "Sphagnum" such as Sphagnol soap have been used for various skin conditions including acne, ringworm, and eczema. The soap was used by the British Red Cross during both World Wars to treat facial wounds and trench sores.


title: Sphagnum

text: Since it is absorptive and extremely acidic, it inhibits growth of bacteria and fungi, so it is used for shipping seeds and live plants.


title: Sphagnum

text: Peat moss is used to dispose of the clarified liquid output (effluent) from septic tanks in areas that lack the proper conditions for ordinary disposal means. It is also used as an environmentally friendly alternative to chlorine in swimming pool sanitation. The moss inhibits the growth of microbes and reduces the need for chlorine in swimming pools.


title: Sphagnum

text: In China, Japan and Korea, long strand dried sphagnum moss is traditionally used as a potting medium for cultivating Vanda falcata orchids.


title: Sphagnum

text: Several of the world's largest wetlands are sphagnum-dominated bogs, including the West Siberian Lowland, the Hudson Bay Lowland and the Mackenzie River Valley. These areas provide habitat for common and rare species. They also store large amounts of carbon, which helps reduce global warming.


title: Sphagnum

text: The U.S. gets up to 80% of sphagnum peat moss it uses from Canada. In Canada, the peat bog mass harvested each year is an estimated 1/60th of the mass that accumulates. About 0.02% of the 1.1 million km (422,000 square miles) of Canadian peat bog are used for peat moss mining. Some efforts are being made to restore peat bogs after peat mining, and some debate exists as to whether the peat bogs can be restored to their premining condition and how long the process takes. "The North American Wetlands Conservation Council estimates that harvested peatlands can be restored to 'ecologically balanced systems' within five to 20 years after peat harvesting." Some wetlands scientists assert that "a managed bog bears little resemblance to a natural one. Like tree farms, these peatlands tend toward monoculture, lacking the biodiversity of an unharvested bog."


title: Sphagnum

text: PittMoss, a peat moss alternative made from recycled newspaper, has emerged as a sustainable substitute in growing media. Coir has also been touted as a sustainable alternative to peat moss in growing media. Another peat moss alternative is manufactured in California from sustainably harvested redwood fiber. Semi-open cell polyurethane materials available in flaked and sheet stock are also finding application as sphagnum replacements with typical usage in green wall and roof garden substrates.


title: Sphagnum

text: In the 2010s, "Sphagnum" peat in Chile has begun to be harvested at a large scale for export to countries like Japan, South Korea, Taiwan and the United States. Given "Sphagnum"’s property to absorb excess water and release it during dry months harvesting of "Sphagnum", means that overexploitation may threaten the water supply in the fjords and channels of Chile. Extraction of "Sphagnum" in Chile is regulated by law since 2 August 2018. Since 2018 Chilean law allows only for the manual extraction of "Sphagnum" using only pitchforks or similar tools as an aid. In a given area (polygon) at least 30% of "Sphagnum" coverage has to be left unharvested. Harvested "Sphagnum" fibers may not exceed 15 cm (6") in length and the remaining "Sphagnum" after harvest may never have a length less than 5 cm (2") over the water table. In the regions of Los Ríos (40°S) and Los Lagos (41–43°S) the same plots may be harvested after 12 years, while further south in Aysén (44–48°S) and Magallanes (49–56°S) 85 years have to pass before the same area is harvested again.


title: Sphagnum

text: Harvesting aside, bogs where "Sphagnum" grows have also come under threat by the development of wind farms in cool humid areas such as the Cordillera del Piuchén where the San Pedro Wind Farm was constructed in the 2010s. The construction of each wind turbine usually implies the removal of vegetation and the alteration of the soil, changing by the way also of the local hydrology.


title: Sphagnum

text: Europe has a long history of the exploitation of peatlands. The Netherlands, for example, once had large areas of peatland, both fen and bog. Between 100 AD and the present, they were drained and converted to agricultural land. The English broadlands have small lakes that originated as peat mines.


title: Sphagnum

text: More than 90% of the bogs in England have been damaged or destroyed. A handful of bogs has been preserved through government buyouts of peat-mining interests. Over longer time scales, however, some parts of England, Ireland, Scotland, and Wales have seen expansion of bogs, particularly blanket bogs, in response to deforestation and abandonment of agricultural land.


title: Sphagnum

text: New Zealand has, like other parts of the world, lost large areas of peatland. The latest estimates for wetland loss in New Zealand are 90% over 150 years. In some cases, better care is taken during the harvesting of "Sphagnum" to ensure enough moss is remaining to allow regrowth. An 8-year cycle is suggested, but some sites require a longer cycle of 11 to 32 years for full recovery of biomass, depending on factors including whether reseeding is done, the light intensity, and the water table. This "farming" is based on a sustainable management program approved by New Zealand's Department of Conservation; it ensures the regeneration of the moss, while protecting the wildlife and the environment. Most harvesting in New Zealand swamps is done only using pitchforks without the use of heavy machinery. During transportation, helicopters are commonly employed to transfer the newly harvested moss from the swamp to the nearest road.


title: Bipartite graph

text: In the mathematical field of graph theory, a bipartite graph (or bigraph) is a graph whose vertices can be divided into two disjoint and independent sets formula_1 and formula_2, that is every edge connects a vertex in formula_1 to one in formula_2. Vertex sets formula_1 and formula_2 are usually called the "parts" of the graph. Equivalently, a bipartite graph is a graph that does not contain any odd-length cycles.


title: Bipartite graph

text: The two sets formula_1 and formula_2 may be thought of as a coloring of the graph with two colors: if one colors all nodes in formula_1 blue, and all nodes in formula_2 red, each edge has endpoints of differing colors, as is required in the graph coloring problem. In contrast, such a coloring is impossible in the case of a non-bipartite graph, such as a triangle: after one node is colored blue and another red, the third vertex of the triangle is connected to vertices of both colors, preventing it from being assigned either color.


title: Bipartite graph

text: One often writes formula_11 to denote a bipartite graph whose partition has the parts formula_1 and formula_2, with formula_14 denoting the edges of the graph. If a bipartite graph is not connected, it may have more than one bipartition; in this case, the formula_15 notation is helpful in specifying one particular bipartition that may be of importance in an application. If formula_16, that is, if the two subsets have equal cardinality, then formula_17 is called a "balanced" bipartite graph. If all vertices on the same side of the bipartition have the same degree, then formula_17 is called biregular.


title: Bipartite graph

text: When modelling relations between two different classes of objects, bipartite graphs very often arise naturally. For instance, a graph of football players and clubs, with an edge between a player and a club if the player has played for that club, is a natural example of an "affiliation network", a type of bipartite graph used in social network analysis.


title: Bipartite graph

text: Another example where bipartite graphs appear naturally is in the (NP-complete) railway optimization problem, in which the input is a schedule of trains and their stops, and the goal is to find a set of train stations as small as possible such that every train visits at least one of the chosen stations. This problem can be modeled as a dominating set problem in a bipartite graph that has a vertex for each train and each station and an edge for each pair of a station and a train that stops at that station.


title: Bipartite graph

text: A third example is in the academic field of numismatics. Ancient coins are made using two positive impressions of the design (the obverse and reverse). The charts numismatists produce to represent the production of coins are bipartite graphs.


title: Bipartite graph

text: In bipartite graphs, the size of minimum vertex cover is equal to the size of the maximum matching; this is Kőnig's theorem. An alternative and equivalent form of this theorem is that the size of the maximum independent set plus the size of the maximum matching is equal to the number of vertices. In any graph without isolated vertices the size of the minimum edge cover plus the size of a maximum matching equals the number of vertices. Combining this equality with Kőnig's theorem leads to the facts that, in bipartite graphs, the size of the minimum edge cover is equal to the size of the maximum independent set, and the size of the minimum edge cover plus the size of the minimum vertex cover is equal to the number of vertices.


title: Bipartite graph

text: Another class of related results concerns perfect graphs: every bipartite graph, the complement of every bipartite graph, the line graph of every bipartite graph, and the complement of the line graph of every bipartite graph, are all perfect. Perfection of bipartite graphs is easy to see (their chromatic number is two and their maximum clique size is also two) but perfection of the complements of bipartite graphs is less trivial, and is another restatement of Kőnig's theorem. This was one of the results that motivated the initial definition of perfect graphs. Perfection of the complements of line graphs of perfect graphs is yet another restatement of Kőnig's theorem, and perfection of the line graphs themselves is a restatement of an earlier theorem of Kőnig, that every bipartite graph has an edge coloring using a number of colors equal to its maximum degree.


title: Bipartite graph

text: According to the strong perfect graph theorem, the perfect graphs have a forbidden graph characterization resembling that of bipartite graphs: a graph is bipartite if and only if it has no odd cycle as a subgraph, and a graph is perfect if and only if it has no odd cycle or its complement as an induced subgraph. The bipartite graphs, line graphs of bipartite graphs, and their complements form four out of the five basic classes of perfect graphs used in the proof of the strong perfect graph theorem.


title: Bipartite graph

text: For a vertex, the number of adjacent vertices is called the degree of the vertex and is denoted formula_20. The degree sum formula for a bipartite graph states that


title: Bipartite graph

text: The degree sequence of a bipartite graph is the pair of lists each containing the degrees of the two parts formula_1 and formula_2. For example, the complete bipartite graph "K" has degree sequence formula_24. Isomorphic bipartite graphs have the same degree sequence. However, the degree sequence does not, in general, uniquely identify a bipartite graph; in some cases, non-isomorphic bipartite graphs may have the same degree sequence.


title: Bipartite graph

text: The bipartite realization problem is the problem of finding a simple bipartite graph with the degree sequence being two given lists of natural numbers. (Trailing zeros may be ignored since they are trivially realized by adding an appropriate number of isolated vertices to the digraph.)


title: Bipartite graph

text: The biadjacency matrix of a bipartite graph formula_15 is a (0,1) matrix of size formula_26 that has a one for each pair of adjacent vertices and a zero for nonadjacent vertices. Biadjacency matrices may be used to describe equivalences between bipartite graphs, hypergraphs, and directed graphs.


title: Bipartite graph

text: A hypergraph is a combinatorial structure that, like an undirected graph, has vertices and edges, but in which the edges may be arbitrary sets of vertices rather than having to have exactly two endpoints. A bipartite graph formula_15 may be used to model a hypergraph in which is the set of vertices of the hypergraph, is the set of hyperedges, and contains an edge from a hypergraph vertex to a hypergraph edge exactly when is one of the endpoints of . Under this correspondence, the biadjacency matrices of bipartite graphs are exactly the incidence matrices of the corresponding hypergraphs. As a special case of this correspondence between bipartite graphs and hypergraphs, any multigraph (a graph in which there may be two or more edges between the same two vertices) may be interpreted as a hypergraph in which some hyperedges have equal sets of endpoints, and represented by a bipartite graph that does not have multiple adjacencies and in which the vertices on one side of the bipartition all have degree two.


title: Bipartite graph

text: A similar reinterpretation of adjacency matrices may be used to show a one-to-one correspondence between directed graphs (on a given number of labeled vertices, allowing self-loops) and balanced bipartite graphs, with the same number of vertices on both sides of the bipartition. For, the adjacency matrix of a directed graph with vertices can be any (0,1) matrix of size formula_28, which can then be reinterpreted as the adjacency matrix of a bipartite graph with vertices on each side of its bipartition. In this construction, the bipartite graph is the bipartite double cover of the directed graph.


title: Bipartite graph

text: It is possible to test whether a graph is bipartite, and to return either a two-coloring (if it is bipartite) or an odd cycle (if it is not) in linear time, using depth-first search. The main idea is to assign to each vertex the color that differs from the color of its parent in the depth-first search forest, assigning colors in a preorder traversal of the depth-first-search forest. This will necessarily provide a two-coloring of the spanning forest consisting of the edges connecting vertices to their parents, but it may not properly color some of the non-forest edges. In a depth-first search forest, one of the two endpoints of every non-forest edge is an ancestor of the other endpoint, and when the depth first search discovers an edge of this type it should check that these two vertices have different colors. If they do not, then the path in the forest from ancestor to descendant, together with the miscolored edge, form an odd cycle, which is returned from the algorithm together with the result that the graph is not bipartite. However, if the algorithm terminates without detecting an odd cycle of this type, then every edge must be properly colored, and the algorithm returns the coloring together with the result that the graph is bipartite.


title: Bipartite graph

text: Alternatively, a similar procedure may be used with breadth-first search in place of depth-first search. Again, each node is given the opposite color to its parent in the search forest, in breadth-first order. If, when a vertex is colored, there exists an edge connecting it to a previously-colored vertex with the same color, then this edge together with the paths in the breadth-first search forest connecting its two endpoints to their lowest common ancestor forms an odd cycle. If the algorithm terminates without finding an odd cycle in this way, then it must have found a proper coloring, and can safely conclude that the graph is bipartite.


title: Bipartite graph

text: For the intersection graphs of formula_29 line segments or other simple shapes in the Euclidean plane, it is possible to test whether the graph is bipartite and return either a two-coloring or an odd cycle in time formula_30, even though the graph itself may have up to formula_31 edges.


title: Bipartite graph

text: Odd cycle transversal is an NP-complete algorithmic problem that asks, given a graph "G" = ("V","E") and a number "k", whether there exists a set of "k" vertices whose removal from "G" would cause the resulting graph to be bipartite. The problem is fixed-parameter tractable, meaning that there is an algorithm whose running time can be bounded by a polynomial function of the size of the graph multiplied by a larger function of "k". The name "odd cycle transversal" comes from the fact that a graph is bipartite if and only if it has no odd cycles. Hence, to delete vertices from a graph in order to obtain a bipartite graph, one needs to "hit all odd cycle", or find a so-called odd cycle transversal set. In the illustration, every odd cycle in the graph contains the blue (the bottommost) vertices, so removing those vertices kills all odd cycles and leaves a bipartite graph.


title: Bipartite graph

text: The "edge bipartization" problem is the algorithmic problem of deleting as few edges as possible to make a graph bipartite and is also an important problem in graph modification algorithmics. This problem is also fixed-parameter tractable, and can be solved in time formula_32, where "k" is the number of edges to delete and "m" is the number of edges in the input graph.


title: Bipartite graph

text: A matching in a graph is a subset of its edges, no two of which share an endpoint. Polynomial time algorithms are known for many algorithmic problems on matchings, including maximum matching (finding a matching that uses as many edges as possible), maximum weight matching, and stable marriage. In many cases, matching problems are simpler to solve on bipartite graphs than on non-bipartite graphs, and many matching algorithms such as the Hopcroft–Karp algorithm for maximum cardinality matching work correctly only on bipartite inputs.


title: Bipartite graph

text: As a simple example, suppose that a set formula_33 of people are all seeking jobs from among a set formula_34 of jobs, with not all people suitable for all jobs. This situation can be modeled as a bipartite graph formula_35 where an edge connects each job-seeker with each suitable job. A perfect matching describes a way of simultaneously satisfying all job-seekers and filling all jobs; Hall's marriage theorem provides a characterization of the bipartite graphs which allow perfect matchings. The National Resident Matching Program applies graph matching methods to solve this problem for U.S. medical student job-seekers and hospital residency jobs.


title: Bipartite graph

text: The Dulmage–Mendelsohn decomposition is a structural decomposition of bipartite graphs that is useful in finding maximum matchings.


title: Bipartite graph

text: Bipartite graphs are extensively used in modern coding theory, especially to decode codewords received from the channel. Factor graphs and Tanner graphs are examples of this. A Tanner graph is a bipartite graph in which the vertices on one side of the bipartition represent digits of a codeword, and the vertices on the other side represent combinations of digits that are expected to sum to zero in a codeword without errors. A factor graph is a closely related belief network used for probabilistic decoding of LDPC and turbo codes.


title: Bipartite graph

text: In computer science, a Petri net is a mathematical modeling tool used in analysis and simulations of concurrent systems. A system is modeled as a bipartite directed graph with two sets of nodes: A set of "place" nodes that contain resources, and a set of "event" nodes which generate and/or consume resources. There are additional constraints on the nodes and edges that constrain the behavior of the system. Petri nets utilize the properties of bipartite directed graphs and other properties to allow mathematical proofs of the behavior of systems while also allowing easy implementation of simulations of the system.


title: Bipartite graph

text: In projective geometry, Levi graphs are a form of bipartite graph used to model the incidences between points and lines in a configuration. Corresponding to the geometric property of points and lines that every two lines meet in at most one point and every two points be connected with a single line, Levi graphs necessarily do not contain any cycles of length four, so their girth must be six or more.


title: Spring roll

text: Spring rolls are rolled appetizers or dim sum commonly found in Chinese and other Southeast Asian cuisines. The kind of wrapper, fillings, and cooking technique used, as well as the name, vary considerably within this large area, depending on the region's culture.


title: Spring roll

text: Spring rolls were a seasonal food consumed during the spring, and started as a pancake filled with the new season's spring vegetables, a welcome change from the preserved foods of the long winter months.


title: Spring roll

text: In Chinese cuisine, spring rolls are savory rolls with cabbage and other vegetable fillings inside a thinly wrapped cylindrical pastry. They are usually eaten during the Spring Festival in mainland China, hence the name. Meat varieties, particularly pork, are also popular. Fried spring rolls are generally small and crisp. They can be sweet or savory; the former often with red bean paste filling, and the latter are typically prepared with vegetables. They are fully wrapped before being pan-fried or deep-fried.


title: Spring roll

text: Non-fried spring rolls are typically bigger and more savory. Unlike fried spring rolls, non-fried spring rolls are typically made by filling the wrapping with pre-cooked ingredients. Traditionally, they are a festive food eaten during the Cold Food Day festival and the Tomb Sweeping Day festival in spring to remember and pay respect to ancestors. The Hakka population sometimes also eat spring rolls on the third day of the third month of the lunar calendar (三月三 sān yuè sān). The wrappings can be a flour-based mix or batter.


title: Spring roll

text: Spring roll is a fried dish usually available as a dim sum. They typically contain minced pork, shredded carrot, bean sprouts and other vegetables served with dipping sauce.


title: Spring roll

text: In Taiwan, the most commonly eaten non-fried spring rolls are "popiah", called "rùn bǐng" () in Mandarin or "po̍h-piáⁿ" () in Hokkien. In northern Taiwan, the ingredients are generally flavored with herbs, stir-fried, and sometimes topped with a finely ground peanut powder before being wrapped. In southern Taiwan, the ingredients are generally boiled or blanched in plain water. Sometimes caster or super fine sugar is added along with the peanut powder before all the ingredients are wrapped.


title: Spring roll

text: "Lumpia" is the name for spring rolls in Indonesia and the Philippines, which was derived from Southern Chinese spring rolls. The name "lumpia" derives from Hokkien "lunpia" () and was introduced in the Philippine islands during the 17th century. It is a savoury snack made of thin crepe pastry skin enveloping a mixture of savoury fillings, consists of chopped vegetables; carrots, cabbages, green beans, bamboo shoots, banana heart and leeks, or sometimes also minced meat; chicken, shrimp, pork or beef. It is often served as an appetizer or snack, and might be served deep fried or fresh (unfried). In both Malaysia, Singapore and Thailand, it is called "popiah" similar as in Taiwan while in Myanmar, it is referred as "kawpyan" (ကော်ပြန့်).


title: Spring roll

text: In Cambodia it is called nem jien. It requires almost the same ingredients as the other recipes from its neighboring countries but Cambodians also use vermicelli noodles and taro root or daikon radish. Cambodians also make their own tangy dipping sauce to dip the spring rolls in.


title: Spring roll

text: The fried version with minced pork is called imperial rolls or "chả giò" (southern Vietnam), "nem cuốn", "chả cuốn" or "Nem rán" (northern Vietnam). They are often called "egg rolls" in Western countries, which is a misnomer. Central Vietnam has its own version of a fried roll called “ram”. Ram is always made from whole shell-on shrimp or chopped de-shelled shrimp and some green onions, wrapped in rice paper and deep fried. Ram, like most specialty food items from central Vietnam, are not widely available in Vietnamese restaurants overseas.


title: Spring roll

text: A Vietnamese imperial roll is different from a Chinese spring roll in that it is typically smaller and contains ground or chopped meats/seafood such as pork, crab, shrimp, chicken, taro or cassava, glass noodles, wood-ear fungi or oyster mushrooms, and shredded carrots. Rice paper is traditionally used as the wrappers. However, there are several Vietnamese restaurants in Western countries that may use Chinese spring roll wrappers due to the unavailability of rice paper or ease of use.


title: Spring roll

text: Spring rolls or summer rolls are a Vietnamese delicacy known as “gỏi cuốn”. Depending on region, salad rolls were made differently. Some vegetarian families make vegetarian spring rolls rather than meat spring rolls. However, the typical ingredients include slivers of cooked pork (most often cha pork sausages), shrimp, sometimes chicken or tofu, fresh herbs like basil or cilantro, lettuce, cucumbers, sometimes fresh garlic, chives, rice vermicelli, all wrapped in moistened rice paper. A typical “gỏi cuốn” may contain boiled pork, boiled rice noodle, cucumber, carrot and herb only. Fresh Vietnamese spring rolls can be made at home or found at Vietnamese restaurants and some grocery stores. They are served at room temperature with dipping sauce. Nước chấm, tương xào, or a hoisin peanut sauce are all common dipping sauces. A typical hoisin dipping sauce includes chili, hoisin sauce, peanut butter and sugar. A standard "nước mắm pha" (nước chấm) dipping sauce is composed of fish sauce, lime, garlic, sugar, and chilies or simply fish sauce, sugar and vinegar.


title: Spring roll

text: In Australia, a diverse range of authentic Asian cuisine is available due to immigration, multiculturalism, and the abundant fresh local produce. Both dim sims and Chiko Rolls were inspired by Chinese spring rolls.


title: Spring roll

text: Australians also have their own version of a spring roll that can be found in many fish and chip shops in Australia and also bought from a supermarket (Chiko Roll). Rather than using pastry with a rolling technique they have a more doughy texture.


title: Spring roll

text: In Austria and Germany, deep-fried spring rolls are called "Frühlingsrolle", while the Vietnamese salad rolls are called "Sommerrolle" ("summer roll"). The French call them "nem" for the fried ones, and "rouleaux de printemps" for the others, whereas in Poland they are known as "sajgonki", named after Saigon, the city from which many of the Vietnamese immigrants in Poland originated.


title: Spring roll

text: In the Netherlands and Belgium, spring rolls are known as "loempia" and are deep-fried or sometimes baked. They are thought to have been introduced by immigrants (including Chinese) from Indonesia, a former colony of the Netherlands. Loempias are filled with bean sprouts, chopped omelette, and sliced chicken or crab. It's also getting more common for loempias to appear with sweet and spicy sauce.


title: Spring roll

text: In the Nordic countries, they are known as "vårrullar/er" (Swedish/Norwegian), "forårsruller" (Danish), or "kevätkääryle" (Finnish).


title: Spring roll

text: In Brazil, spring rolls are called either "rolinhos-primavera" (), which is an approximate free translation from English, or as it is called in Japanese restaurants and among people who are used to the plate by the way it came to Brazil from Japanese immigrants, (). They can be found mostly in Chinese restaurants, usually served with a "molho agridoce" (sweet and sour sauce) to dip, usually bright red and hot, made with ketchup, vinegar, sugar and sometimes spices such as star anise, which accompanies some other kinds of dishes, and can include onion and sweet pepper. Some Japanese restaurants also serve spring rolls in Brazil, but generally plain or with soy sauce to dip ("molho agridoce" is also available in some). They are also found in buffet-like fast food restaurants, and can be called either by the Japanese or Brazilian Portuguese name, but most often the latter.


title: Spring roll

text: In Chile, spring rolls are called "arrollado primavera", and supermarkets, street vendors and Chinese restaurants sell them. (However, in other countries, "arrollado primavera" refers to a savory pinwheel-type roll made with thin sponge cake and should not be confused with the Chilean version.)


title: Spring roll

text: In Costa Rica, spring rolls are called in Spanish "rollito de primavera" ("little spring roll"), but is popular known as "Taco Chino" and is offered in almost all the Chinese restaurants as an entree or appetizer.


title: Spring roll

text: In Mexico, spring rolls are called "rollos primavera" (which translates directly to "spring rolls"), and are sold in many Chinese restaurants and fast-food establishments accompanied with sweet and sour or soy sauces. On the northwest border with the US, specially in Mexicali, Baja California, the spring rolls are known as "chunkun"; this name could be related to the Korean chungwon (춘권). They are deep-fried and they are usually served with ketchup topped with a dot of hot mustard as dipping sauce.


title: Spring roll

text: In Argentina and Uruguay, spring rolls are commonly known as "empanaditas chinas" (Chinese turnover) and also "arrolladitos primavera" (which translates directly to "spring rolls"), and supermarkets and Chinese restaurants sell them. They are a common treat carried by catering services, and usually served with a small bowl of sweet and sour sauce to dip them in.


title: Spring roll

text: In Venezuela, spring rolls are called "lumpia" as in the Philippines and Indonesia. Many Chinese restaurants sell them, and they are usually served with sweet and sour or soy sauce.


title: Boeing–Sikorsky RAH-66 Comanche

text: The Boeing–Sikorsky RAH-66 Comanche is an American stealth armed reconnaissance and attack helicopter designed for the United States Army. Following decades of development, the RAH-66 program was canceled in 2004 before mass production began, by which point nearly US$7 billion had been spent on the program.


title: Boeing–Sikorsky RAH-66 Comanche

text: During the early 1980s, the U.S. Army started to formulate requirements for the replacement of its helicopters then in service, which resulted in the launch of the Light Helicopter Experimental (LHX) program. Nearly a decade later, following the refinement of requirements, evaluation of submissions, and the rebranding of the program as the "Light Helicopter" (LH) program, during April 1991, the Army announced the selection of the Boeing–Sikorsky team's design as the contest winner, shortly after which a contract for construction of prototypes was awarded. The Comanche was to incorporate several advanced elements, such as stealth technologies, and a number of previously untried design features. Operationally, it was to employ advanced sensors in its reconnaissance role, in which it was intended to designate targets for the AH-64 Apache. It was also armed with one rotary cannon and could carry missiles and rockets in internal bays and optionally on stub wings for light attack duties.


title: Boeing–Sikorsky RAH-66 Comanche

text: Two RAH-66 prototypes were constructed and underwent flight testing between 1996 and 2004. On 1 June 2000, the program entered its $3.1 billion engineering and manufacturing development (EMD) phase. However, during 2002, the Comanche program underwent heavy restructuring; the number of Comanches that were to be purchased was cut to 650. At the time, the projected total cost for the full production of the Comanche in such numbers stood at $26.9 billion. As early as the late 1990s, the Government Accountability Office (GAO) had reported that it had "serious doubts" about the program, observing that the Comanche would "consume almost two thirds of the whole Aviation budget by Fiscal Year 2008". Multiple government agencies had acted to cut the number of Comanches on order, but, as a consequence of the heavy reductions to the numbers to be procured, the unit costs soared.


title: Boeing–Sikorsky RAH-66 Comanche

text: On 23 February 2004, the U.S. Army announced the termination of the Comanche program, stating they had determined that the RAH-66 would require numerous upgrades to be viable on the battlefield and that the service would instead direct the bulk of its rotary systems funds to renovating its existing attack, utility, and reconnaissance helicopters. The Army also announced new plans to accelerate the development of unmanned aerial vehicles (UAVs), which could also perform the scouting role intended for the Comanche, but with less risk. Since program cancellation, both of the prototypes have been placed on public display.


title: Boeing–Sikorsky RAH-66 Comanche

text: During 1982, the U.S. Army initiated the Light Helicopter Experimental (LHX) program with the aim of producing a replacement for several existing rotorcraft, including the UH-1, AH-1, OH-6, and OH-58 helicopters. Then in 1988 a formal request for proposal (RFP) was issued to various manufacturers; the requirement had evolved into a battlefield reconnaissance helicopter by this time. In October 1988, the Army announced two teams, these being Boeing–Sikorsky and Bell–McDonnell Douglas, received contracts to further develop their concepts. During the 1990s, the program's name was changed from LHX to simply "Light Helicopter" (LH). In April 1991, the Army awarded the Boeing–Sikorsky team a $2.8 billion contract to complete six prototypes. Later that month the helicopter was officially named "RAH-66 Comanche".