Overview of models.

There are many different learning styles models; one literature review identified 71 different models. Only a few models are described below.

David Kolb's model.

David A. Kolb's model is based on his experiential learning model, as explained in his book "Experiential Learning". Kolb's model outlines two related approaches toward grasping experience: "Concrete Experience" and "Abstract Conceptualization", as well as two related approaches toward transforming experience: "Reflective Observation" and "Active Experimentation". According to Kolb's model, the ideal learning process engages all four of these modes in response to situational demands; they form a learning cycle from experience to observation to conceptualization to experimentation and back to experience. In order for learning to be effective, Kolb postulated, all four of these approaches must be incorporated. As individuals attempt to use all four approaches, they may tend to develop strengths in one experience-grasping approach and one experience-transforming approach, leading them to prefer one of the following four learning styles:  Kolb's model gave rise to the Learning Style Inventory, an assessment method used to determine an individual's learning style. According to this model, individuals may exhibit a preference for one of the four styles — Accommodating, Converging, Diverging and Assimilating — depending on their approach to learning in Kolb's experiential learning model.  Although Kolb's model is widely accepted with substantial empirical support and has been revised over the years, a 2013 study pointed out that Kolb's Learning Style Inventory, among its other weaknesses, incorrectly dichotomizes individuals on the abstract/concrete and reflective/action dimensions of experiential learning (in much the same way as the Myers-Briggs Type Indicator does in a different context), and proposed instead that these dimensions be treated as continuous rather than dichotomous/binary variables.

Peter Honey and Alan Mumford's model.

Peter Honey and Alan Mumford adapted Kolb's experiential learning model. First, they renamed the stages in the learning cycle to accord with managerial experiences: "having" an experience, "reviewing" the experience, "concluding" from the experience, and "planning" the next steps. Second, they aligned these stages to four learning styles named:  These four learning styles are assumed to be acquired preferences that are adaptable, either at will or through changed circumstances, rather than being fixed personality characteristics. Honey and Mumford's Learning Styles Questionnaire (LSQ) is a self-development tool and differs from Kolb's Learning Style Inventory by inviting managers to complete a checklist of work-related behaviours without directly asking managers how they learn. Having completed the self-assessment, managers are encouraged to focus on strengthening underutilised styles in order to become better equipped to learn from a wide range of everyday experiences.  A MORI survey commissioned by The Campaign for Learning in 1999 found the Honey and Mumford LSQ to be the most widely used system for assessing preferred learning styles in the local government sector in the UK.

Learning modalities.

Walter Burke Barbe and colleagues proposed three learning modalities (often identified by the acronym VAK):  Barbe and colleagues reported that learning modality strengths can occur independently or in combination (although the most frequent modality strengths, according to their research, are visual or mixed), they can change over time, and they become integrated with age. They also pointed out that learning modality "strengths" are different from "preferences"; a person's self-reported modality preference may not correspond to their empirically measured modality strength. This disconnect between strengths and preferences was confirmed by a subsequent study. Nevertheless, some scholars have criticized the VAK model. Psychologist Scott Lilienfeld and colleagues have argued that much use of the VAK model is nothing more than pseudoscience or a psychological urban legend.

Neil Fleming's VAK/VARK model.

Neil Fleming's VARK model and inventory expanded upon earlier notions of sensory modalities such as the VAK model of Barbe and colleagues and the representational systems (VAKOG) in neuro-linguistic programming. The four sensory modalities in Fleming's model are:  Fleming claimed that visual learners have a preference for seeing (visual aids that represent ideas using methods other than words, such as graphs, charts, diagrams, symbols, etc.). Subsequent neuroimaging research has suggested that visual learners convert words into images in the brain and vice versa, but some psychologists have argued that this "is not an instance of learning styles, rather, it is an instance of ability appearing as a style". Likewise, Fleming claimed that auditory learners best learn through listening (lectures, discussions, tapes, etc.), and tactile/kinesthetic learners prefer to learn via experience—moving, touching, and doing (active exploration of the world, science projects, experiments, etc.). Students can use the model and inventory to identify their preferred learning style and, it is claimed, improve their learning by focusing on the mode that benefits them the most. Fleming's model also posits two types of multimodality. This means that not everyone has one defined preferred modality of learning; some people may have a mixture that makes up their preferred learning style.

Anthony Gregorc's model.

Anthony Gregorc and Kathleen Butler organized a model describing different learning styles rooted in the way individuals acquire and process information differently. This model posits that an individual's perceptual abilities are the foundation of his or her specific learning strengths, or learning styles.  In this model, there are two perceptual qualities: "concrete" and "abstract", and two ordering abilities: "random" and "sequential". Concrete perceptions involve registering information through the five senses, while abstract perceptions involve the understanding of ideas, qualities, and concepts which cannot be seen. In regard to the two ordering abilities, sequential ordering involves the organization of information in a linear, logical way, and random ordering involves the organization of information in chunks and in no specific order. The model posits that both of the perceptual qualities and both of the ordering abilities are present in each individual, but some qualities and ordering abilities are more dominant within certain individuals.  There are four combinations of perceptual qualities and ordering abilities based on dominance: "concrete sequential", "abstract random", "abstract sequential", and "concrete random". The model posits that individuals with different combinations learn in different ways—they have different strengths, different things make sense to them, different things are difficult for them, and they ask different questions throughout the learning process.  The validity of Gregorc's model has been questioned by Thomas Reio and Albert Wiswell following experimental trials. Gregorc argues that his critics have "scientifically-limited views" and that they wrongly repudiate the "mystical elements" of "the spirit" that can only be discerned by a "subtle human instrument".

Cognitive approaches.

Anthony Grasha and Sheryl Riechmann, in 1974, formulated the Grasha-Reichmann Learning Style Scale. It was developed to analyze the attitudes of students and how they approach learning. The test was originally designed to provide teachers with insight on how to approach instructional plans for college students. Grasha's background was in cognitive processes and coping techniques. Unlike some models of cognitive styles which are relatively nonjudgmental, Grasha and Riechmann distinguish between adaptive and maladaptive styles. The names of Grasha and Riechmann's learning styles are:  Aiming to explain why aptitude tests, school grades, and classroom performance often fail to identify real ability, Robert Sternberg listed various cognitive dimensions in his book "Thinking Styles". Several other models are also often used when researching cognitive styles; some of these models are described in books that Sternberg co-edited, such as "Perspectives on Thinking, Learning, and Cognitive Styles".

NASSP model.

In the 1980s, the National Association of Secondary School Principals (NASSP) formed a task force to study learning styles. The task force defined three broad categories of style—cognitive, affective, and physiological—and 31 variables, including the perceptual strengths and preferences from the VAK model of Barbe and colleagues, but also many other variables such as need for structure, types of motivation, time of day preferences, and so on. They defined a learning style as "a "gestalt"—not an amalgam of related characteristics but greater than any of its parts. It is a composite of internal and external operations based in neurobiology, personality, and human development and reflected in learner behavior."  According to the NASSP task force, styles are hypothetical constructs that help to explain the learning (and teaching) process. They posited that one can recognize the learning style of an individual student by observing his or her behavior. Learning has taken place only when one observes a relatively stable change in learner behavior resulting from what has been experienced.

Assessment methods.

Learning Style Inventory.

The Learning Style Inventory (LSI) is connected with David A. Kolb's model and is used to determine a student's learning style. Previous versions of the LSI have been criticized for problems with validity, reliability, and other issues. Version 4 of the Learning Style Inventory replaces the four learning styles of previous versions with nine new learning styles: initiating, experiencing, imagining, reflecting, analyzing, thinking, deciding, acting, and balancing. The LSI is intended to help employees or students "understand how their learning style impacts upon problem solving, teamwork, handling conflict, communication and career choice; develop more learning flexibility; find out why teams work well—or badly—together; strengthen their overall learning."  A completely different Learning Styles Inventory is associated with a binary division of learning styles, developed by Richard Felder and Linda Silverman. In Felder and Silverman's model, learning styles are a balance between pairs of extremes such as: Active/Reflective, Sensing/Intuitive, Verbal/Visual, and Sequential/Global. Students receive four scores describing these balances. Like the LSI mentioned above, this inventory provides overviews and synopses for teachers.

NASSP Learning Style Profile.

The NASSP Learning Style Profile (LSP) is a second-generation instrument for the diagnosis of student cognitive styles, perceptual responses, and study and instructional preferences. The LSP is a diagnostic tool intended as the basis for comprehensive style assessment with students in the sixth to twelfth grades. It was developed by the National Association of Secondary School Principals research department in conjunction with a national task force of learning style experts. The Profile was developed in four phases with initial work undertaken at the University of Vermont (cognitive elements), Ohio State University (affective elements), and St. John's University (physiological/environmental elements). Rigid validation and normative studies were conducted using factor analytic methods to ensure strong construct validity and subscale independence.  The LSP contains 23 scales representing four higher order factors: cognitive styles, perceptual responses, study preferences and instructional preferences (the affective and physiological elements). The LSP scales are: analytic skill, spatial skill, discrimination skill, categorizing skill, sequential processing skill, simultaneous processing skill, memory skill, perceptual response: visual, perceptual response: auditory, perceptual response: emotive, persistence orientation, verbal risk orientation, verbal-spatial preference, manipulative preference, study time preference: early morning, study time preference: late morning, study time preference: afternoon, study time preference: evening, grouping preference, posture preference, mobility preference, sound preference, lighting preference, temperature preference.

Other methods.

Other methods (usually questionnaires) used to identify learning styles include Neil Fleming's VARK Questionnaire and Jackson's Learning Styles Profiler. Many other tests have gathered popularity and various levels of credibility among students and teachers.

In the classroom.

Various researchers have attempted to hypothesize ways in which learning style theory can be used in the classroom. Two such scholars are Rita Dunn and Kenneth Dunn, who build upon a learning modalities approach.  Although learning styles will inevitably differ among students in the classroom, Dunn and Dunn say that teachers should try to make changes in their classroom that will be beneficial to every learning style. Some of these changes include room redesign, the development of small-group techniques, and the development of "contract activity packages". Redesigning the classroom involves locating dividers that can be used to arrange the room creatively (such as having different learning stations and instructional areas), clearing the floor area, and incorporating student thoughts and ideas into the design of the classroom.  Dunn and Dunn's "contract activity packages" are educational plans that use: a clear statement of the learning need; multisensory resources (auditory, visual, tactile, kinesthetic); activities through which the newly mastered information can be used creatively; the sharing of creative projects within small groups; at least three small-group techniques; a pre-test, a self-test, and a post-test.  Another scholar who believes that learning styles should have an effect on the classroom is Marilee Sprenger in "Differentiation through Learning Styles and Memory". She bases her work on three premises:  Sprenger details how to teach in visual, auditory, or tactile/kinesthetic ways. Methods for visual learners include ensuring that students can see words written, using pictures, and drawing timelines for events. Methods for auditory learners include repeating words aloud, small-group discussion, debates, listening to books on tape, oral reports, and oral interpretation. Methods for tactile/kinesthetic learners include hands-on activities (experiments, etc.), projects, frequent breaks to allow movement, visual aids, role play, and field trips. By using a variety of teaching methods from each of these categories, teachers cater to different learning styles at once, and improve learning by challenging students to learn in different ways.  James W. Keefe and John M. Jenkins have incorporated learning style assessment as a basic component in their "personalized instruction" model of schooling. Six basic elements constitute the culture and context of personalized instruction. The cultural components—teacher role, student learning characteristics, and collegial relationships—establish the foundation of personalization and ensure that the school prizes a caring and collaborative environment. The contextual factors—interactivity, flexible scheduling, and authentic assessment—establish the structure of personalization.  According to Keefe and Jenkins, cognitive and learning style analysis have a special role in the process of personalizing instruction. The assessment of student learning style, more than any other element except the teacher role, establishes the foundation for a personalized approach to schooling: for student advisement and placement, for appropriate retraining of student cognitive skills, for adaptive instructional strategy, and for the authentic evaluation of learning. Some learners respond best in instructional environments based on an analysis of their perceptual and environmental style preferences: most individualized and personalized teaching methods reflect this point of view. Other learners, however, need help to function successfully in "any" learning environment. If a youngster cannot cope under conventional instruction, enhancing his cognitive skills may make successful achievement possible.  Many of the student learning problems that learning style diagnosis attempts to solve relate directly to elements of the human information processing system. Processes such as attention, perception and memory, and operations such as integration and retrieval of information are internal to the system. Any hope for improving student learning necessarily involves an understanding and application of information processing theory. Learning style assessment can provide a window to understanding and managing this process.  At least one study evaluating teaching styles and learning styles, however, has found that congruent groups have no significant differences in achievement from incongruent groups. Furthermore, learning style in this study varied by demography, specifically by age, suggesting a change in learning style as one gets older and acquires more experience. While significant age differences did occur, as well as no experimental manipulation of classroom assignment, the findings do call into question the aim of congruent teaching–learning styles in the classroom.  Educational researchers Eileen Carnell and Caroline Lodge concluded that learning styles are not fixed and that they are dependent on circumstance, purpose and conditions.

Criticism.

Learning style theories have been criticized by many scholars and researchers. Some psychologists and neuroscientists have questioned the scientific basis for separating out students based on learning style. According to Susan Greenfield the practice is "nonsense" from a neuroscientific point of view: "Humans have evolved to build a picture of the world through our senses working in unison, exploiting the immense interconnectivity that exists in the brain." Similarly, Christine Harrington argued that since all students are multisensory learners, educators should teach research-based general learning skills.  Many educational psychologists have shown that there is little evidence for the efficacy of most learning style models, and furthermore, that the models often rest on dubious theoretical grounds. According to professor of education Steven Stahl, there has been an "utter failure to find that assessing children's learning styles and matching to instructional methods has any effect on their learning." Professor of education Guy Claxton has questioned the extent that learning styles such as VARK are helpful, particularly as they can have a tendency to label children and therefore restrict learning. Similarly, psychologist Kris Vasquez pointed out a number of problems with learning styles, including the lack of empirical evidence that learning styles are useful in producing student achievement, but also her more serious concern that the use of learning styles in the classroom could lead students to develop self-limiting implicit theories about themselves that could become self-fulfilling prophecies that are harmful, rather than beneficial, to the goal of serving student diversity.  Some research has shown that long-term retention can better be achieved under conditions that seem more difficult, and that teaching students only in their preferred learning style is not effective.  Psychologists Scott Lilienfeld, Barry Beyerstein, and colleagues listed as one of the "50 great myths of popular psychology" the idea that "students learn best when teaching styles are matched to their learning styles", and they summarized some relevant reasons not to believe this "myth".

Critique made by Coffield et al..

A 2004 non-peer-reviewed literature review by authors from the University of Newcastle upon Tyne criticized most of the main instruments used to identify an individual's learning style. In conducting the review, Frank Coffield and his colleagues selected 13 of the most influential models of the 71 models they identified, including most of the models cited on this page. They examined the theoretical origins and terms of each model, and the instrument that purported to assess individuals against the learning styles defined by the model. They analyzed the claims made by the author(s), external studies of these claims, and independent empirical evidence of the relationship between the learning style identified by the instrument and students' actual learning. Coffield's team found that none of the most popular learning style theories had been adequately validated through independent research.  One of the most widely known theories assessed by Coffield's team was the learning styles model of Dunn and Dunn. This model is widely used in schools in the United States, and 177 articles have been published in peer-reviewed journals referring to this model. The conclusion of Coffield and colleagues was: "Despite a large and evolving research programme, forceful claims made for impact are questionable because of limitations in many of the supporting studies and the lack of independent research on the model."  Coffield's team claimed that another model, Anthony Gregorc's Gregorc Style Delineator, was "theoretically and psychometrically flawed" and "not suitable for the assessment of individuals".

Critique of Kolb's model.

Mark K. Smith compiled and reviewed some critiques of Kolb's model in his article, "David A. Kolb on Experiential Learning". According to Smith's research, there are six key issues regarding the model:  The most recent work by Kolb that Smith cites is from 2005, and he does not address the changes in the 2015 edition of Kolb's book "Experiential Learning".

Other critiques.

Coffield and his colleagues and Mark Smith are not alone in their judgements. In 2005, Demos, a UK think tank, published a report on learning styles prepared by a group chaired by David Hargreaves that included Usha Goswami from the University of Cambridge and David Wood from the University of Nottingham. The Demos report said that the evidence for learning styles was "highly variable", and that practitioners were "not by any means always frank about the evidence for their work".  Cautioning against interpreting neuropsychological research as supporting the applicability of learning style theory, John Geake, Professor of Education at the UK's Oxford Brookes University, and a research collaborator with Oxford University's Centre for Functional Magnetic Resonance Imaging of the Brain, commented in 2005: "We need to take extreme care when moving from the lab to the classroom. We do remember things visually and aurally, but information isn't defined by how it was received."  The work of Daniel T. Willingham, a cognitive psychologist and neuroscientist, has argued that there is not enough evidence to support a theory describing the differences in learning styles amongst students. In his 2009 book "Why Don't Students Like School", he claimed that a cognitive styles theory must have three features: "it should consistently attribute to a person the same style, it should show that people with different abilities think and learn differently, and it should show that people with different styles do not, on average, differ in ability". He concluded that there are no theories that have these three crucial characteristics, not necessarily implying that cognitive styles don't exist but rather stating that psychologists have been unable to "find them". In a 2008 self-published YouTube video titled "Learning Styles Don't Exist", Willingham concluded by saying: "Good teaching is good teaching and teachers don't need to adjust their teaching to individual students' learning styles."  In 2019, the American Association of Anatomists published a study that investigated whether learning styles had any effect on the final outcomes of an anatomy course. The study found that even when being told they had a specific learning style, the students did not change their study habits, and those students that did use their theoretically dominant learning style had no greater success in the course; specific study strategies, unrelated to learning style, were positively correlated with final course grade.

2009 APS critique.

In late 2009, the journal "Psychological Science in the Public Interest" of the Association for Psychological Science (APS) published a report on the scientific validity of learning styles practices. The panel of experts that wrote the article, led by Harold Pashler of the University of California, San Diego, concluded that an adequate evaluation of the learning styles hypothesis—the idea that optimal learning demands that students receive instruction tailored to their learning styles—requires a particular kind of study. Specifically, students should be grouped into the learning style categories that are being evaluated (e.g., visual learners vs. verbal learners), and then students in each group must be randomly assigned to one of the learning methods (e.g., visual learning or verbal learning), so that some students will be "matched" and others will be "mismatched". At the end of the experiment, all students must sit for the same test. If the learning style hypothesis is correct, then, for example, visual learners should learn better with the visual method, whereas auditory learners should learn better with the auditory method. As disclosed in the report, the panel found that studies utilizing this essential research design were virtually absent from the learning styles literature. In fact, the panel was able to find only a few studies with this research design, and all but one of these studies were negative findings—that is, they found that the same learning method was superior for all kinds of students. Examples of such negative findings include the research of Laura J. Massa and Richard E. Mayer, as well as more recent research since the 2009 review.  Furthermore, the panel noted that, even if the requisite finding were obtained, the benefits would need to be large, and not just statistically significant, before learning style interventions could be recommended as cost-effective. That is, the cost of evaluating and classifying students by their learning style, and then providing customized instruction would need to be more beneficial than other interventions (e.g., one-on-one tutoring, after school remediation programs, etc.).  As a consequence, the panel concluded, "at present, there is no adequate evidence base to justify incorporating learning styles assessments into general educational practice. Thus, limited education resources would better be devoted to adopting other educational practices that have strong evidence base, of which there are an increasing number."  The article incited critical comments from some defenders of learning styles. "The Chronicle of Higher Education" reported that Robert Sternberg from Tufts University spoke out against the paper: "Several of the most-cited researchers on learning styles, Mr. Sternberg points out, do not appear in the paper's bibliography." This charge was also discussed by "Science", which reported that Pashler said, "Just so... most of [the evidence] is 'weak'." "The Chronicle" reported that even David A. Kolb partly agreed with Pashler; Kolb said: "The paper correctly mentions the practical and ethical problems of sorting people into groups and labeling them. Tracking in education has a bad history."

Subsequent critiques.

A 2015 review paper examined the studies of learning styles completed after the 2009 APS critique, giving particular attention to studies that used the experimental methods advocated for by Pashler et al. The findings were similar to those of the APS critique: the evidence for learning styles was virtually nonexistent while evidence contradicting it was both more prevalent and used more sound methodology. Follow-up studies concluded that learning styles had no effect on student retention of material whereas another explanation, dual coding, had a substantial impact on it and held more potential for practical application in the classroom.  A 2017 research paper from the UK found that 90% of academics agreed there are "basic conceptual flaws" with learning styles theory, yet 58% agreed that students "learn better when they receive information in their preferred learning style", and 33% reported that they used learning styles as a method in the past year. It concluded that it might be better to use methods that are "demonstrably effective".

Learning styles refer to a range of competing and contested theories that aim to account for differences in individuals' learning. The many theories share the proposition that humans can be classified according to their'style' of learning, but differ in how the proposed styles should be defined, categorized and assessed. A common concept is that individuals differ in how they learn.

通常认为大多数人都有自己一些特殊的认识事物、理解事物以及处理刺激或信息的模式。基于这一观念,“学习风格”的思想起源于1970年代,近年来获得普及。学习风格是假定能够使个人达到最佳学习状态的方法。这一理论提议教师应该评估其学生的学习风格,并使其课堂教学方法能够最适合每个学生的学习风格。


History.

1984–2001: Early years and growth.

Research In Motion Limited was founded in March 1984 by Mike Lazaridis and Douglas Fregin. At the time, Lazaridis was an engineering student at the University of Waterloo while Fregin was an engineering student at the University of Windsor. In 1988, RIM became the first wireless data technology developer in North America and the first company outside Scandinavia to develop connectivity products for Mobitex wireless packet-switched data communications networks. In 1990, RIM introduced the DigiSync Film KeyKode Reader. In 1991, RIM introduced the first Mobitex protocol converter. In 1992, RIM introduced the first Mobitex point-of-sale solution, a protocol converter box that interfaced with existing point-of-sale terminal equipment to enable wireless communication. In 1993, RIM introduced the RIMGate, the first general-purpose Mobitex X.25 gateway. In the same year, RIM launched Ericsson Mobidem AT and Intel wireless modem containing RIM modem firmware. In 1994, RIM introduced the first Mobitex mobile point-of-sale terminal. In the same year, RIM received the Emmy Award for Technical Innovation and the KPMG High Technology Award. In 1995, RIM introduced Freedom, the first Type II PCMCIA radio modem for Mobitex.  In 1995, RIM was

2001–2011: Global expansion and competition.

RIM soon began to introduce BlackBerry devices aimed towards the consumer market as well, beginning with the BlackBerry Pearl 8100the first BlackBerry phone to include multimedia features such as a camera. The introduction of the Pearl series was highly successful, as was the subsequent Curve 8300 series and Bold 9000. Extensive carrier partnerships fuelled the rapid expansion of BlackBerry users globally in both enterprise and consumer markets.  Despite the arrival of the first Apple iPhone in 2007, BlackBerry sustained unprecedented market share growth well into 2011. The introduction of Apple's iPhone on the AT&T network in the fall of 2007 in the United States prompted RIM to produce its first touchscreen smartphone for the competing network in 2008the BlackBerry Storm. The Storm sold well but suffered from mixed to poor reviews and poor customer satisfaction. The iPhone initially lagged behind the BlackBerry in both shipments and active users, due to RIM's head start and larger carrier distribution network. In the United States, the BlackBerry user base peaked at approximately 21 million users in the fall of 2010. That quarter, the company's global subscriber base stood at 36 million users. As the iPhone and Google Android accelerated growth in the United States, the BlackBerry began to turn to

2011–2015: Strategic changes and restructuring.

Slowing growth prompted the company to undertake a lay-off of 2,000 employees in the summer of 2011. In September 2011, the company's BlackBerry Internet Service suffered a massive outage, impacting millions of customers for several days. The outage embarrassingly occurred as Apple prepared to launch the iPhone 4S, causing fears of mass defections from the platform.  Shortly afterwards, in October 2011, RIM unveiled BBX, a new platform for future BlackBerry smartphones that would be based on the same QNX-based platform as the PlayBook. However, due to an accusation of trademark infringement regarding the name BBX, the platform was renamed BlackBerry 10. The task proved to be daunting, with the company delaying the launch in December 2011 to some time in 2012. On January 22, 2012, Mike Lazaridis and Jim Balsillie resigned as the CEOs of the company, handing the reins over to executive Thorsten Heins. On March 29, 2012, the company reported its first net loss in years. Heins set about the task of restructuring the company, including announcing plans to lay off 5,000 employees, replacing numerous executives, and delaying the new QNX-based operating system for phones ("BlackBerry 10") a second time into January 2013.

BlackBerry 10.

After much criticism and numerous delays, RIM officially launched BlackBerry 10 and two new smartphones based off the platform, the BlackBerry Z10 and Q10, on January 30, 2013. The BlackBerry Z10, the first BlackBerry smartphone running BlackBerry 10, debuted worldwide in January 2013, going on sale immediately in the U.K. with other countries following. A marked departure from previous BlackBerry phones, the Z10 featured a fully touch-based design, a dual-core processor, and a high-definition display. BlackBerry 10 had 70,000 applications available at launch, which the company expected would rise to 100,000 by the time the device made its debut in the United States. In support of the launch, the company aired its first Super Bowl television advertisement in the U.S. and Canada during Super Bowl XLVII. In discussing the decision to create a proprietary operating system instead of adopting an off-the-shelf platform such as Android, Heins noted, "If you look at other suppliers' ability to differentiate, there's very little wiggle room. We looked at it seriouslybut if you understand what the promise of BlackBerry is to its user base it's all about getting stuff done.

Prem-Watsa/Fairfax Deal.

Canada Pension Plan Investment Board's CEO Mark Wiseman stated that he would consider investing in BlackBerry if the company became private. Also on August 12, 2013, foremost shareholder Prem Watsa resigned from BlackBerry's board.  On September 20, 2013, the company announced it would lay off 4,500 staff and take a CAD$1 billion operating loss. Three days later, the company announced that it had signed a letter of intent to be acquired by a

John Chen Joins BlackBerry.

On November 4, 2013, the Fairfax Prem Watsa deal was scrapped in favor of a US$1 billion cash injection which, according to one analyst, represented the level of confidence BlackBerry's largest shareholder had in the company. At the same time, BlackBerry installed John Chen as CEO to replace the laid-off Heins. According to the Globe and Mail, BlackBerry's hope was that Chen, with his reputation as a turnaround artist, could save the company.  "John Chen knows how to manage a mobile company, and perhaps most importantly, can make things happen in the industry," J. Gold Associates Principal Analyst Jack Gold told the publication.  "We have begun moving the company to embrace a multi-platform, BYOD world by adopting a new mobility management platform and a new device strategy," Chen explained in an open letter published shortly after his appointment. "I believe in the value of this brand. With the right team and the right strategy in place, I am confident that

2015–present: Software transition.

In the first quarter of the 2015 fiscal year, Chen stated: "This is, of course, the very beginning of our task and we hope that we will be able to report better results going forward... We feel pretty good about where we are." "Quartz" reported that stock was up by 30 percent, compared to the same period in the previous year, while Chen expressed enthusiasm for the release of two new handsets, both with keyboards and touch screens, in the second half of 2014. Chen did not provide sales figures for the Z3 phone in Indonesia.  In September 2015, Chen unveiled the BlackBerry Priv, a keyboard-slider smartphone utilizing the Android operating system with BlackBerry-developed software enhancements, including a secure bootloader, full-disk encryption, integrity protection, and the BlackBerry HUB.

Strategic acquisitions.

During this time, BlackBerry also expanded its software and services offerings with several key acquisitions. These included file security firm WatchDox, crisis communications leader AtHoc, and rival EMM vendor Good Technology. The products offered by these firms were gradually re-branded and integrated into BlackBerry's own portfolio.  Trefis, an analyst team and Forbes contributor, called Good "a nice strategic fit for BlackBerry's software business", noting that the acquisition would "help improve BlackBerry's

Hardware licensing partnerships.

BlackBerry announced the DTEK50, a mid-range Android smartphone, on July 26, 2016. Unlike the Priv, the DTEK50 was a re-branded version of an existing smartphone, the Alcatel Idol 4 as manufactured by TCL Corporation, one of the company's hardware partners. It was to be the second-last phone ever developed in-house at BlackBerry, followed by the DTEK60 in October 2016 - on September 28, 2016, BlackBerry announced that it would cease in-house hardware development to focus on software, delegating development, design,

Cybersecurity consulting.

In February 2016, BlackBerry acquired UK-based cybersecurity firm Encription, with the intention of branching out into the security consulting business. It later released BlackBerry SHIELD, an IT risk

BlackBerry Secure.

On December 8, 2016, BlackBerry announced the release of BlackBerry Secure. Billed as a "comprehensive mobile security platform for the Enterprise of Things", BlackBerry Secure further deepens the integration between BlackBerry's acquisitions and its core portfolio. According to Forbes, it brings all of BlackBerry's products "under a single umbrella".  On February 7, 2017, BlackBerry announced the creation of the BBM Enterprise SDK, a Communication-Platform-as-a-Service development tool. The Enterprise SDK allows developers to incorporate BBM Enterprise's messaging functionality into their applications. It was released to BlackBerry's partners on February 21, 2017, and officially launched on June 12, 2017.  Also in February 2017, analyst firm 451 Research released a report on BlackBerry's improved financial position and product focus. The report identified BlackBerry's position in the Internet of Things and its device licensing strategy as strengths. The BBM Enterprise SDK was also highlighted, alongside several challenges still facing the company.

Financials.

Until 2013, the number of active BlackBerry users increased over time.  For the fiscal period in which the Apple iPhone was first released (in 2007), RIM reported a user base of 10.5 million BlackBerry subscribers.  At the end of 2008, when Google Android first hit the market, RIM reported that the number of BlackBerry subscribers had increased to 21 million.  In the fourth quarter of fiscal year ended March 3, 2012, RIM shipped 11.1 million BlackBerry smartphones, down 21 percent from the previous quarter and it was the first decline in the quarter covering Christmas since 2006. For its fourth quarter, RIM announced a net loss of US$125 million (the last loss before this occurred in the fourth quarter of the fiscal year 2005). RIM's loss of market share accelerated in 2011, due to the rapidly growing sales of Samsung and HTC Android handsets; RIM's annual market share in the U.S. dropped to just 3 percent, from 9 percent.  In the quarter ended June 28, 2012, RIM announced that the number of BlackBerry subscribers had reached 78 million globally. Furthermore, RIM reported its first quarter revenue for the 2013 fiscal year, showing that the company incurred a GAAP net loss of US$518 million for the quarter, and announced a plan to implement a US$1 billion cost-saving initiative. The company also announced the delay of the new BlackBerry 10 OS until the first quarter of 2013.  After the release of the Apple iPhone 5 in September 2012, RIM CEO Thorsten Heins announced that the number of global users was up to 80 million, which sparked a 7% jump in shares. On December 2, 2012, the company reported a decline in revenue of 5% from the previous quarter and 47% from the

Organizational changes.

Leadership changes.

The company was often criticized for its dual CEO structure. Under the original organization, Mike Lazaridis oversaw technical functions, while Jim Balsillie oversaw sales/marketing functions. Some saw this arrangement as a dysfunctional management structure and believed RIM acted as two companies, slowing the effort to release the new BlackBerry 10 operating system.  On June 30, 2011, an investor push for the company to split its dual-CEO structure was unexpectedly withdrawn after an agreement was made with RIM. RIM announced that after

Workforce reductions.

In June 2011, RIM announced its prediction that Q1 2011 revenue would drop for the first time in nine years, and also unveiled plans to reduce its workforce.  In July 2011, the company cut 2,000 jobs, the biggest lay-off in its history and the first major layoff since November 12, 2002 when the company laid off 10% of its workforce (200 employees). The lay-off reduced the workforce by around 11%, from 19,000 employees to 17,000.  On June 28, 2012, the company announced a planned workforce reduction of 5,000 by the end of

Stock fluctuations.

In June 2011, RIM stock fell to its lowest point since 2006. On December 16, 2011, RIM shares fell to their lowest price since January 2004. Overall in 2011, the share price tumbled 80 percent from January to December, causing its market capitalization to fall below book value. By March 2012, shares were worth less than $14, from a high of over $140 in 2008. From June 2008 to June 2011, RIM's shareholders lost almost $70 billion, or 82 percent, as the company's market capitalization dropped from $83 billion to $13.6 billion, the biggest decline among communications-equipment providers.  Shares price fell further on July 16, closing at $7.09 on the Toronto Stock Exchange, the lowest level since September 8, 2003, after a jury in California said RIM must pay $147.2 million as a result of a patent infringement judgment that was subsequently overturned.  On November 22, 2012, shares of RIM/BlackBerry surged 18%, the largest gain of the stock in over three years. This was due to National Bank of Canada analyst Kris Thompson's announcement that the new BB10 devices were expected to sell better than anticipated; along with raising the target stock price.  On June 28, 2013, after BlackBerry announced net losses of approximately $84 million, its shares plunged 28%.  On April 12, 2017, shares surged more than 19% as BlackBerry won an arbitration case against Qualcomm. It was decided that BlackBerry had been overpaying the company in royalty payments, and BlackBerry was awarded $814.9 million.

Rumoured Samsung buyout.

On January 14, 2015, in the final hour of trading in U.S. markets, Reuters published that Samsung was in talks with BlackBerry to buy the

Mobile OS Transition.

BlackBerry OS (Java).

The existing Java-based BlackBerry OS was intended to operate under much different, simpler conditions such as low powered devices, narrow network bandwidth, and high-security enterprises. However, as the needs of the mobile user evolved, the aging platform struggled with emerging trends like mobile web browsing, consumer applications, multimedia and touch screen interfaces. Users could experience performance issues, usability problems and instability.  The company tried to

BlackBerry Tablet OS (QNX).

The BlackBerry PlayBook was the first RIM product whose BlackBerry Tablet OS was built on QNX, launched in April 2011 as an alternative to the Apple iPad. However, it was criticized for having incomplete software (it initially lacked

BlackBerry 10 (QNX).

BlackBerry 10, a substantially updated version of BlackBerry Tablet OS intended for the next generation BlackBerry smartphones, was originally planned for release in early 2012. The company delayed

Android.

In September 2015, BlackBerry announced the Priv, a handset running Android 5.1.1 "Lollipop" (and compatible with an upgrade to Android Marshmallow). It is the first phone by the company not to run an in-house built operating system.  BlackBerry's Android is almost stock Android, with their own tweaks to improve productivity and security. BlackBerry has implemented some of the features of BlackBerry 10 within Android like BlackBerry Hub, BlackBerry Virtual Keyboard, BlackBerry Calendar, BlackBerry Contacts app etc.  On April 1, 2016, BlackBerry reported that it sold 600,000 phones in its fiscal fourth quarter, amid expectations of 750,000–800,000 handset sales for the

Acquisitions.

Through the years, particularly as the company evolved towards its new platform, BlackBerry has made numerous acquisitions of third-party companies and technology.

Slipstream Data Inc..

Slipstream Data Inc was a network optimization/data compression/network acceleration software company. BlackBerry acquired

Certicom.

Certicom Corp. is a cryptography company founded in 1985 by Gordon Agnew, Ron Mullin and Scott Vanstone.  The Certicom intellectual property portfolio includes over 350 patents and patents pending worldwide that cover key aspects of elliptic-curve cryptography (ECC): software optimizations, efficient hardware implementations, methods to enhance the security, and various cryptographic protocols.  The National Security Agency (NSA) has licensed 26 of Certicom's ECC patents as

Dash Navigation.

In June 2009, RIM announced they

Torch Mobile.

In August 2009, RIM acquired Torch Mobile, developer of Iris Browser, enabling the inclusion of a WebKit-based browser on their BlackBerry devices, which became the

DataViz.

On September 8, 2010, DataViz, Inc. sold their office suite Documents To Go and other assets to Research In

Viigo.

On March 26, 2010, the company announced its acquisition of Viigo, a Toronto-based company that

QNX.

RIM reached an agreement with Harman International on April 12, 2010, for RIM to acquire QNX Software Systems. The

The Astonishing Tribe.

The Astonishing Tribe (TAT), a user interface design company based in Malmö, Sweden, was acquired by the company on December 2,

JayCut.

In July 2011, RIM brought on JayCut, a Sweden-based company that

Paratek Microwave.

In March 2012, RIM acquired Paratek

Tungle.me.

On September 18, 2012, it was announced that the RIM social

Newbay.

In July 2011, RIM acquired NewBay, an Irish-based company that is an online

Scoreloop.

On June 7, 2011, Scoreloop was acquired by BlackBerry for US$71 million. It provided tools for adding

Gist.

Gist was acquired in February 2011, by BlackBerry. Gist is a tool that helps users to organise

Scroon.

BlackBerry Ltd. acquired Scroon in May 2013. The French startup manages Facebook, Twitter and other social-media accounts for large clients like luxury-good maker LVMH Moet Hennessy Louis Vuitton SA, wireless operator Orange SA (ORA) and Warner Bros. Entertainment.

Movirtu.

Movirtu was acquired in September 2014, by BlackBerry. Movirtu is a U.K. startup that allows multiple phone numbers to be

Secusmart.

Secusmart was acquired in September 2014. The German-based company was one of the steps to position BlackBerry as the most secure provider in the mobile market. Secusmart had the

WatchDox.

WatchDox was an Israel-based Enterprise File Synchronization and Sharing company which specialized in securing access to documents on a cloud

AtHoc.

On July 22, 2015, BlackBerry announced that

Good Technology.

On September 4, 2015, BlackBerry announced the acquisition of mobile security provider Good Technology for $425 million. On

Encription.

On February 24, 2016,

Cylance.

On November 16, 2018 Cylance was purchased for US$1.4 billion by BlackBerry Limited in an all cash deal. The technology behind

Software.

BlackBerry Unified Endpoint Manager (UEM).

An Enterprise Mobility Management platform that provides provisional and access control over smartphones, tablets, laptops, and desktops with support for all major platforms including iOS,

BlackBerry Dynamics (Formerly Good Dynamics).

A Mobile Application Management platform that manages and secures app data through application virtualization. The BlackBerry Dynamics suite of apps includes

BlackBerry Workspaces (Formerly WatchDox).

An Enterprise File Synchronization and Sharing (EFSS) platform,

BlackBerry 2FA (Formerly Strong Authentication).

A two-factor, certificate-based VPN authentication solution

BBM Enterprise.

An IP-based enterprise instant messaging platform that provides end-to-end encryption for voice, video, and text-based communication. On February 7, 2017, Blackberry released the

BlackBerry AtHoc.

An emergency communication system, AtHoc provides two-way messaging and notifications across a range of devices and platforms. On May 17, 2017, BlackBerry released AtHoc Account to help businesses more easily keep track of their staff in an emergency.

SecuSUITE.

An anti-eavesdropping solution that provides voice, data, and SMS encryption.

BlackBerry QNX.

A real-time embedded operating system, QNX drives multiple software systems in modern auto

Patent litigation.

Since the turn of the century, RIM has been embroiled in a series of suits relating to alleged patent infringement.

Glenayre Electronics.

In 2001, Research In Motion sued competitor Glenayre Electronics Inc. for patent infringement, partly in response to an earlier infringement

Good Technologies.

In June 2002, Research In Motion filed suit against 2000 start-up and competitor Good

Handspring.

On September 16, 2002, Research In Motion was awarded a patent pertaining to keyboard design on hand-held e-mail devices. Upon

NTP.

During the appeals, RIM discovered new prior art that raised a "substantial new question of patentability" and filed for a reexamination of the NTP patents in the United States Patent and Trademark Office. That reexamination was conducted separately to the court cases for infringement. In February 2006, the USPTO rejected all of NTP's claims in three disputed patents. NTP appealed the decision, and the reexamination

Xerox.

On July 17, 2003, while still embroiled in litigation with NTP and Good Technology, RIM filed suit against Xerox in the U.S.

Visto.

On May 1, 2006, RIM was sued by Visto for infringement of four patents. Though the patents were widely considered invalid and in the same veins

Motorola.

On January 22, 2010, Motorola requested that all BlackBerry smartphones be banned from being imported into the United States for infringing upon five of Motorola's patents. Their patents for "early-stage

Eatoni.

On December 5, 2011, Research In Motion obtained an order granting its motion to dismiss plaintiff Eatoni's claims that RIM violated Section 2 of the Sherman Antitrust Act and

Mformation.

In July 2012, a U.S. federal court jury awarded damages (later overturned) of $147 million against Research In Motion. The jury decided that Research In Motion had violated patents of Mformation and calculated damages of $8 each on 18.4 million units for royalties on

Qualcomm.

On May 26, 2017, BlackBerry announced that it had reached an agreement with Qualcomm Incorporated resolving all amounts payable in connection with the interim arbitration decision announced on April 12, 2017. Following a

Facebook.

On March 8, 2018, Blackberry Limited sued Facebook Inc. in federal court in Los Angeles. According to BlackBerry Limited, Facebook has built swaths of its empire on the

Controversies.

Stock option scandal settlement.

In 2007, co-CEO Jim Balsillie was forced to resign as chairman as the company announced a $250-million earnings restatement relating to mistakes in how it granted stock options. Furthermore, an internal review found that hundreds of stock-option grants had been backdated, timed to a low share price to make them more lucrative.  In January 2009, Canadian regulators stated that they were seeking a record penalty of US$80 million from the top two executives, co-CEOs Jim Balsillie and Mike Lazaridis. Furthermore, the Ontario Securities Commission (OSC) has pushed for Balsillie to pay the bulk of any penalty and relinquish his seat on

Environmental record.

In November 2011, RIM was ranked 15th out of 15 electronics manufacturers in Greenpeace’s re-launched Guide to Greener Electronics. The guide ranks manufacturers according to their policies and practices to reduce their impact on the climate, produce greener products, and make their operations more sustainable. RIM appeared for the first time in 2011 with a score of 1.6 out of 10. In the Energy section the company was criticized by Greenpeace for not seeking external verification for its data on

Anonymous open letter to management.

On June 30, 2011, an alleged anonymous senior RIM employee penned an open letter to the company's senior management. The

Service outages.

On October 10, 2011, RIM experienced one of the worst service outages in the company's history. Tens of millions of BlackBerry users in Europe, the Middle East, Africa, and North America were unable to receive or send emails and

Government access to communication.

After a four-year stand-off with the Indian government over access to RIM's secure networks, the company demonstrated a solution that can intercept consumer email and messaging

BlackBerry Limited is a Canadian multinational company specialising in enterprise software and the Internet of things. Originally known as Research In Motion (RIM), it is best known to the general public as the former developer of the BlackBerry brand of smartphones, and tablets. It transitioned to an enterprise software and services company under CEO John S. Chen. Its products are used by various businesses, car makers, and government agencies. They include BlackBerry Cylance's artificial intelligence based cyber-security solutions, the BlackBerry AtHoc emergency communication system (ECS) platform; the QNX real-time operating system; and BlackBerry Enterprise Server (BlackBerry Unified Endpoint Manager), a Unified Endpoint Management (UEM) platform. BlackBerry was founded in 1984 as Research In Motion by Mike Lazaridis and Douglas Fregin. In 1992, Lazaridis hired Jim Balsillie, and Lazaridis and Balsillie served as co-CEOs until January 22, 2012, when Thorsten Heins became president and CEO. In November 2013, John S. Chen took over as CEO. His initial strategy was to subcontract manufacturing to Foxconn, and to focus on software technology. Currently, his strategy includes forming licensing partnerships with device manufacturers such as TCL Communication and unifying BlackBerry's software portfolio.

黑莓公司(英语:BlackBerry Limited,前称英语:Research in Motion (RIM),意为「行动研究」),是加拿大的一家通信公司。由迈克·拉扎里迪斯与道格拉斯·弗莱根共同创立,总部位于加拿大安大略省的滑铁卢市。主要产品为手提通讯设备黑莓手机,QNX操作系统,及黑莓企业通讯系统(BlackBerry Enterprise Server)。其保安性能为产品的主要特点。消费者较为熟悉的黑莓手机,曾经是北美最受欢迎智能手机,广为行政人员爱戴。自苹果公司及谷歌加入竞争后,市场占有率已被抛离,2016年中国TCL公司取得BlackBerry全球授权,将由以下各家印度Optiemus、印尼BB Merah Putih及中国TCL,等3家各自独立分开制造生产与销售黑莓品牌的移动设备。2020年2月,TCL宣布将于2020年8月29日后不再生产、设计和销售黑莓手机。


Formation.

The pyranose ring is formed by the reaction of the hydroxyl group on carbon 5 (C-5) of a sugar with the aldehyde at carbon 1. This forms an intramolecular hemiacetal. If reaction is between the C-4 hydroxyl and the aldehyde, a furanose is formed instead. The pyranose form is thermodynamically more stable than the furanose form, which can be seen by the distribution of these two cyclic forms in solution.

History.

Hermann Emil Fischer won the Nobel Prize in Chemistry (1902) for his work in determining the structure of the -aldohexoses. However, the linear, free-aldehyde structures that Fischer proposed represent a very minor percentage of the forms that hexose sugars adopt in solution. It was Edmund Hirst and Clifford Purves, in the research group of Walter Haworth, who conclusively determined that the hexose sugars preferentially form a pyranose, or six-membered, ring. Haworth drew the ring as a flat hexagon with groups above and below the plane of the ring – the Haworth projection.  A further refinement to the conformation of pyranose rings came when Sponsler and Dore (1926) realized that Sachse’s mathematical treatment of six-membered rings could be applied to their X-ray structure of cellulose. It was determined that the pyranose ring is puckered, to allow all of the carbon atoms of the ring to have close to the ideal tetrahedral geometry.

Conformations.

This puckering leads to a total of 38 distinct basic pyranose conformations: 2 chairs, 6 boats, 6 skew-boats, 12 half-chairs, and 12 envelopes.  These conformers can interconvert with one another; however, each form may have very different relative energy, so a significant barrier to interconversion may be present. The energy of these conformations can be calculated from quantum mechanics; an example of possible glucopyranose interconversions is given.  The conformations of the pyranose ring are superficially similar to that of the cyclohexane ring. However, the specific nomenclature of pyranoses includes reference to the ring oxygen, and the presence of hydroxyls on the ring have distinct effects on its conformational preference. There are also conformational and stereochemical effects specific to the pyranose ring.

Nomenclature.

To name conformations of pyranose, first the conformer is determined. The common conformers are similar to those found in cyclohexane, and these form the basis of the name. Common conformations are chair (C), boat (B), skew (S), half-chair (H) or envelope (E). The ring atoms are then numbered; the anomeric, or hemiacetal, carbon is always 1. Oxygen atoms in the structure are, in general, referred to by the carbon atom they are attached to in the acyclic form, and designated O. Then:

NMR spectroscopy.

As shown by the relative structure energies in the diagram above, the chair structures are the most stable carbohydrate form. This relatively defined and stable conformation means that the hydrogen atoms of the pyranose ring are held at relatively constant angles to one another. Carbohydrate NMR takes advantage of these dihedral angles to determine the configuration of each of the hydroxyl groups around the ring.

Pyranose is a collective term for saccharides that have a chemical structure that includes a six-membered ring consisting of five carbon atoms and one oxygen atom. There may be other carbons external to the ring. The name derives from its similarity to the oxygen heterocycle pyran, but the pyranose ring does not have double bonds. A pyranose in which the anomeric OH at C(l) has been converted into an OR group is called a pyranoside.

吡喃糖(英语:Pyranose)是一种糖,用于总称碳水化合物所具有的化学结构,其中包含一个由5个碳原子和1个氧原子所组成的六元环状结构。可能会有其他的碳原子在环以外。吡喃糖是吡喃的衍生物,但是吡喃糖环没有双键。如果吡喃糖1号碳上的异头羟基已经变为OR基团则被称为吡喃糖苷。


Sanskrit.

In Vedic Sanskrit, the anusvāra (lit. "after-sound" or "subordinate sound") was an allophonic (derived) nasal sound.  The exact nature of the sound has been subject to debate. The material in the various ancient phonetic treatises points towards different phonetic interpretations, and these discrepancies have historically been attributed to either differences in the description of the same pronunciation or to dialectal or diachronic variation. In a 2013 reappraisal of the evidence, Cardona concludes that these reflect real dialectal differences.  The environments in which the anusvara could arise, however, were well defined. In the earliest Vedic Sanskrit, it was an allophone of /m/ at a morpheme boundary, or of /n/ within morphemes, when it was preceded by a vowel and followed by a fricative (). In later Sanskrit its use expanded to other contexts, first before /r/ under certain conditions, then, in Classical Sanskrit, before and. Later still, gave anusvara as an alternative pronunciation in word-final sandhi, and later treatises also prescribed it at morpheme junctions and within morphemes. In the later written language, the diacritic used to represent anusvara was optionally used to indicate a nasal stop having the same place of articulation as a following plosive.

Devanagari script.

In the Devanagari script, anusvara is represented with a dot ("bindu") above the letter (e.g. मं). In the International Alphabet of Sanskrit Transliteration (IAST), the corresponding symbol is ṃ ("m" with an underdot). Some transcriptions render notation of phonetic variants used in some Vedic shakhas with variant transcription (ṁ).  In writing Sanskrit, the anusvara is often used as an alternative representation of the nasal stop with the same place of articulation as the following plosive. For example, 'limb (of the body)' may be written with either a conjunct, अङ्ग "aṅga", or with an anusvara, अंग "aṃga". A variant of the anusvara, the anunāsika or 'candrabindu', was used more explicitly for nasalized vowels, as in अँश "aṃśa" for 'portion'.

Hindi.

In Standard Hindi, the is traditionally defined as representing a nasal consonant homorganic to a following plosive, in contrast to the (), which indicates vowel nasalization. In practice, however, the two are often used interchangeably.  The precise phonetic value of the phoneme, whether it is represented by or, is dependent on the phonological environment.  Word-finally it is realized as nasalization of the preceding vowel: ', "a well". It results in vowel nasalization also medially between a short vowel and a non-obstruent (' "a youth",'"a long-handled axe") and, in native words, between a long vowel and a voiceless plosive (' "tooth",'"a snake",'"tail").  It is pronounced as a homorganic nasal, with the preceding vowel becoming nasalized allophonically, in the following cases: between a long vowel and a voiced plosive (' "copper",'"silver"), between a long vowel and a voiceless plosive in loanwords (' "repressed",'"a bank",'), and between a short vowel and an obstruent (' "to support", "" "a chest").  The last rule has two sets of exceptions where the effects only a nasalization of the preceding short vowel. Words from the first set are morphologically derived from words with a long nasalized vowel (', "to be divided" from ', "to divide"; ', "irrigation" from ', "to irrigate"). In suchs cases, the vowel is sometimes denasalized (, instead of, ). The second set is composed of a few words like "(", "to arrive" and ', "to laugh").

Marathi.

In Marathi the anusvara is pronounced as a nasal that is homorganic to the following consonant (with the same place of articulation). For example, it is pronounced as the dental nasal न् before dental consonants, as the bilabial nasal म् before bilabial consonants, etc.

Nepali.

In Nepali, chandrabindu and anusvara have the same pronunciation similarly to Hindi. Therefore, there is a great deal of variation regarding which occurs in any given position. Many words containing anusvara thus have alternative spellings with chandrabindu instead of anusvara and vice versa.

Other Indic script languages.

Anusvara is used in other languages using Indic scripts as well, usually to represent suprasegmental phones (such as phonation type or nasalization) or other nasal sounds.

Bengali.

In the Bengali script, the anusvara diacritic (অনুস্বার "onushshar" in Bengali) is written as a circle above a slanted line (ং), and represents. It is used in the name of the Bengali language বাংলা. It has merged in pronunciation with the letter ঙ "ungô" in Bengali. Although the anusvara is a consonant in Bengali phonology, it is nevertheless treated in the written system as a diacritic in that it is always directly adjacent to the preceding consonant, even when consonants are spaced, apart in titles or banners: বাং-লা-দে-শ "bang-la-de-sh", not বা-ং-লা-দে-শ "ba-ng-la-de-sh" for বাংলাদেশ "Bangladesh" It is never pronounced with the inherent vowel "ô", and it cannot take a vowel sign (instead, the consonant ঙ "ungô" is used pre-vocalically).

Burmese.

In the Burmese script, the anusvara ( "auk myit" ) is represented as a dot underneath a nasalised final to indicate a creaky tone (with a shortened vowel). Burmese also uses a dot above to indicate the nasalized ending (called "Myanmar Sign Anusvara" in Unicode), called "thay thay tin" ()

Sinhala.

In the Sinhala script, the anusvara is not a nonspacing combining mark but a spacing combining mark. It has circular shape and follows its base letter ( ං). It is called in Sinhala, which means "dot". The anusvara represents at the end of a syllable. It is used in fact, in the name of the Sinhala language සිංහල. It has merged in pronunciation with the letter ඞ ṅa in Sinhala.

Telugu.

The Telugu script has full-zero (anusvāra) ం, half-zero (arthanusvāra) and "visarga" to convey various shades of nasal sounds. Anusvara is represented as a circle shape after a letter: క - ka and కం - kam.

Thai.

The equivalent of the anusvara in the Thai alphabet is the "nikkhahit", which is used when rendering Sanskrit and Pali texts. It is written as an open circle above the consonant (for example ) and its pronunciation depends on the following sound: if it is a consonant then the nikkhahit is pronounced as a homorganic nasal, and if it is at the end of a word it is pronounced as the velar nasal.

Anunasika.

Anunasika ("") is a form of vowel nasalization, often represented by an anusvara. It is a form of open mouthed nasalization, akin to the nasalization of vowels followed by "n" or "m" in Parisian French. When "n" or "m" follow a vowel, the "n" or "m" becomes silent and causes the preceding vowel to become nasal (pronounced with the soft palate extended downward so as to allow part or all of the air to leave through the nostrils). Anunasika is sometimes called a "subdot" because of its IAST representation.  In Devanagari and related orthographies, it is represented by the chandrabindu diacritic ("example": मँ ).  In Burmese, the anunasika, called () and represented as, creates the nasalized ending when it is attached as a dot above a letter. The anunasika represents the -m final in Pali.

Unicode.

Unicode encodes anusvara and anusvara-like characters for a variety of scripts:

Anusvara (Sanskrit: "") is a symbol used in many Indic scripts to mark a type of nasal sound, typically transliterated. Depending on its location in the word and the language for which it is used, its exact pronunciation can vary. In the context of ancient Sanskrit, "anusvara" is the name of the particular nasal sound itself, regardless of written representation.

随韵(anusvara、、IAST:""),是用于各种印度语言中的表示鼻音化的一种变音符号。依据 anusvara 在词中的位置和语言的不同,它的精确发音可能变化得非常大。


Early years.

Nigel Godrich was born in Westminster, London, the son of Victor Godrich, a BBC sound supervisor, and Brenda Godrich. He was educated at William Ellis School in North London, where he shared classes with his friend and future Zero 7 member Henry Binns. Godrich began playing guitar, inspired by Jimi Hendrix and Frank Zappa. He became interested in sound engineering and studied at the School of Audio Engineering. After graduating, Godrich became a junior staff member at the Audio One studio complex, working primarily as a tea boy.  After the closure of Audio One, Godrich became the house engineer at RAK Studios, where he became a tape operator for producer John Leckie, with whom he worked on albums by Ride and Denim. In 1995, Godrich left RAK to work with Binns on electronic dance music at their collective Shabang studio. Within six months he began working with mainstream acts including McAlmont & Butler.  Godrich credited producer Phil Thornalley for teaching him his craft. He named his "heroes" as Beatles producer George Martin, for "inventing the job", and Trevor Horn, for being "the thing that really made me sit up and listen".

Radiohead.

Godrich first worked with Radiohead when Leckie hired him to engineer two songs for their 1994 EP "My Iron Lung." The band nicknamed him "Nihilist", approving of his efforts to take their sound in new directions. He went on to engineer Radiohead's second album "The Bends" (1995), working under Leckie as producer. When Leckie left the studio to attend a social engagement, Radiohead and Godrich stayed to record B-sides; one of the songs intended for a B-side, "Black Star", was instead included on the album. In 1995, Godrich produced Radiohead's charity single "Lucky", plus the B-sides "Bishop's Robes" and "Talk Show Host", released on the "Street Spirit (Fade Out)" single.  Radiohead invited Godrich to produce their third album, "OK Computer" (1997). Working in improvised studios without supervision, he and the band learned as they went, and credited the open process with the record's success. In 2013, Godrich told the "Guardian": ""OK Computer" was such a big thing for me because I was given power for the first time. Some of these incredibly intelligent and insightful people said 'do what you want' to me so I worked my arse off for them and together we did something that represents where we all were at the time. And it stuck for some reason. People got it, so that changed my life."  Godrich has produced every Radiohead studio album since, and won the Grammy Award for Best Engineered Non-Classical Album for "Hail to the Thief" (2003). Godrich's father died during the recording of Radiohead's ninth album, "A Moon Shaped Pool" (2016); Godrich wrote: "Making this album was a very intense experience for me. I lost my dad in the process. Hence a large piece of my soul lives here in a good way."  In 2006, CBC described Godrich's longtime collaboration with Radiohead as "the most adventurous band-producer partnership in modern rock". He has been dubbed the "sixth member" of the band, in an allusion to George Martin being called the "Fifth Beatle". In 2016, Godrich said: "I can only ever have one band like Radiohead who I've worked with for this many years. That’s a very deep and profound relationship. The Beatles could only have ever had one George Martin; they couldn’t have switched producers halfway through their career. All that work, trust, and knowledge of each other would have been thrown out of the window and they’d have to start again."

Thom Yorke and Atoms for Peace.

Godrich has produced most of Radiohead singer Thom Yorke's solo work, including his albums "The Eraser "(2006), "Tomorrow's Modern Boxes "(2014) and "Anima" (2019). Yorke credits Godrich with helping edit his work, identifying which parts need improvement and which have potential. He gave the example of "Black Swan", a song from "The Eraser", which originally was "a six-minute load of crap, except for this one juicy bit, and [Godrich] goes past and goes, 'That bit. Fuck the rest.' Usually it's something like that."  In 2009, to perform songs from "The Eraser," Godrich and Yorke formed Atoms for Peace, with Godrich on guitar, keyboards and synthesisers. The band also includes bassist Flea of the Red Hot Chili Peppers, drummer Joey Waronker of Beck and R.E.M., and percussionist Mauro Refosco of Forro in the Dark. In February 2013, they released an album, "Amok", produced by Godrich, followed by a tour of Europe, the US and Japan.

Other projects.

Following his success with "OK Computer", Godrich mixed most of Natalie Imbruglia's hit album "Left of the Middle" (1997) and R.E.M.'s "Up" (1998). Godrich has collaborated with American singer-songwriter Beck several times, on "Mutations" (1998), "Sea Change" (2002) and "The Information" (2006). The first two of these albums, particularly "Sea Change", were noted for their atmospheric folk/pop sound, a major departure from the sample-heavy, spontaneous style Beck was known for. Godrich has also worked with Travis three times, producing their commercial breakthrough "The Man Who" (1999) and its followup "The Invisible Band" (2001), and co-producing "The Boy With No Name" (2007) with Brian Eno and Mike Hedges.  Godrich produced Pavement's final album "Terror Twilight" (1999), with Radiohead's Jonny Greenwood contributing harmonica on two tracks. In 2016, songwriter Stephen Malkmus described the album as "overproduced" and described conflicts with Godrich. In response, Godrich tweeted: "I literally slept on a friend's floor in NYC to be able to make that album." In 2001, Godrich remixed U2's "Walk On" for its single release, and also mixed and contributed production to Air's albums "Talkie Walkie" (2004) and "Pocket Symphony" (2007).  In 2002, Godrich was hired to produce the second album by the Strokes, but was fired when their work, according to the band, proved "soulless". Godrich said of the failed collaboration: "The problem there was that me and [singer Julian Casablancas] are just too similar, we're both control freaks. He wanted to do it his way, I wanted to do it my way, and obviously that's the point of me being there. And I'm saying 'Well, why am I here if you're not prepared to try and do it the way I want to do it?' We got on great, it was just one of those laughable things where it just doesn't work. I wanted them to change, and they didn't."  He produced the 20th anniversary version of "Do They Know It's Christmas?", released in December 2004, which also featured Yorke and Greenwood. Paul McCartney hired Godrich to produce his album "Chaos and Creation in the Backyard" (2005) after being recommended by Beatles producer George Martin. Godrich fired McCartney's touring band, and demanded that McCartney abandon songs Godrich found clichéd, over-sentimental, or subpar. The album was nominated for several Grammy Awards, including Album of the Year, and Godrich was nominated for Producer of the Year.  In 2010, Godrich worked with Beck to compose the score for "Scott Pilgrim vs. the World", his first film work. In October 2012, Godrich, along with Joey Waronker and singer Laura Bettinson, released an album as Ultraísta. In 2015, he produced the live album "", and made a cameo appearance as a Stormtrooper in "". He mixed the Red Hot Chili Peppers' eleventh studio album, "The Getaway" (2016). Godrich produced the fifth solo album by Roger Waters, "Is This the Life We Really Want?", released in June 2017. Godrich, a fan of Waters' work with Pink Floyd, was critical of Waters' previous solo work and felt his role as producer was to "encourage him, to push him a little bit".

"From the Basement" (2006–2009).

In September 2006, it was announced that Godrich, along with producer Dilly Gent, producer James Chads and John Woollcombe, were shooting the music series "From the Basement", filmed from London's Maida Vale Studios. The series was to focus on intimate, live performances by musicians without a host or an audience. Godrich told Pitchfork Media in an interview, "We've got a lot of people that I'd like to see on the show [that] we're talking to. [But] I don't want to mention their names. Obviously, I'm really interested to capture some really iconic, bigger names– really the whole point is to get people who are having their moment, to try and get a definitive record of what they're doing."  Godrich first conceived "From the Basement" as a means of authentically documenting music being made. Drawing further inspiration from British television music series "The Old Grey Whistle Test", Godrich came upon the idea of a television programme. Despite early reports, "From the Basement" did not initially appear on British television, because of not taking on corporate sponsors.  When the pilot was in production, "From The Basement" was to be an online programme only. However, this was not feasible as it did not generate enough money to produce the episodes to the quality level desired. Instead, the producers went to international TV networks to receive money up front to produce the series. The series did eventually air on television; the first UK broadcast was on Sky Arts on 1 December 2007, featuring four songs performed by Thom Yorke on 8 December 2007. The United States premiere was on Rave HD on 22 February 2008, followed by a run on Independent Film Channel, as part of the network's "Automat" block of television programmes in the autumn of 2008. On 3 November 2008, the series was released on DVD.

Nigel Timothy Godrich (born 28 February 1971) is an English record producer, recording engineer and musician. He is known for his work with the English rock band Radiohead, having produced all their studio albums since "OK Computer" (1997) and most of singer Thom Yorke's solo work. He is a member of Atoms for Peace (with Yorke) and Ultraísta. Godrich has also worked with acts including Beck, Paul McCartney, U2, R.E.M., Pavement and Roger Waters. He is the creator of the music webseries "From the Basement".

尼杰尔·蒂莫西·歌德里希(英语:Nigel Timothy Godrich,1971年-2月28日)是一位英国音乐制作人、音频工程师以及音乐人,以与电台司令的合作而闻名。他担任了乐队自《OK电脑》(1997)以来所有的录音室专辑的制作人,并像披头士乐队的制作人乔治·马丁那样拥有“乐队第六人”的名号。歌德里希与乐队主唱汤姆·约克在其个人作品中也有合作,同时还是原子和平乐队以及过激乐队的成员。与他合作过的音乐人及乐队还有贝克、保罗·麦卡特尼、U2以及R.E.M.等等。


Names.

Synonyms include α-toluic acid, benzeneacetic acid, alpha tolylic acid, 2-phenylacetic acid, and β-phenylacetic acid.

Occurrence.

Phenylacetic acid has been found to be an active auxin (a type of plant hormone), found predominantly in fruits. However, its effect is much weaker than the effect of the basic auxin molecule indole-3-acetic acid. In addition the molecule is naturally produced by the metapleural gland of most ant species and used as an antimicrobial. It is also the oxidation product of phenethylamine in humans following metabolism by monoamine oxidase and subsequent metabolism of the intermediate product, phenylacetaldehyde, by the aldehyde dehydrogenase enzyme; these enzymes are also found in many other organisms.

Preparation.

This compound may be prepared by the hydrolysis of benzyl cyanide:

Applications.

Phenylacetic acid is used in some perfumes, as it possesses a honey-like odor even in low concentrations. It is also used in penicillin G production and diclofenac production. It is also employed to treat type II hyperammonemia to help reduce the amounts of ammonia in a patient's bloodstream by forming phenylacetyl-CoA, which then reacts with nitrogen-rich glutamine to form phenylacetylglutamine. This compound is then excreted from the patient's body. It's also used in the illicit production of phenylacetone, which is used in the manufacture of methamphetamine.  The sodium salt of phenylacetic acid, sodium phenylacetate, is used as a pharmaceteutical drug for the treatment of urea cycle disorders, including as the combination drug sodium phenylacetate/sodium benzoate (Ammonul).  Phenylacetic acid is used in the preparation of several pharmaceutical drugs, including camylofin, bendazol, triafungin, phenacemide, lorcainide, phenindione, and cyclopentolate.

Phenylacetic acid (PAA; conjugate base phenylacetate), also known by various synonyms, is an organic compound containing a phenyl functional group and a carboxylic acid functional group. It is a white solid with a strong honey-like odor. Endogeneously, it is a catabolite of phenylalanine. As a commercial chemical, because it can be used in the illicit production of phenylacetone (used in the manufacture of substituted amphetamines), it is subject to controls in countries including the United States and China.

苯乙酸(英语:PAA, Phenylacetic acid),又名苯醋酸、苄基甲酸,是一种由苄基与羧基相连得到的羧酸,分子式为。室温下为白色有特殊气味的光泽片状或块状结晶,可溶于乙醇、乙醚。可由苯乙腈水解制备。为避免用于违法生产苯基丙酮,在美国和中国受到管制。