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Garlic fingers	Garlic fingers	Garlic fingers (French: Doigts à l'ail) known also as garlic cheese fingers are an Atlantic Canadian dish, similar to a pizza in shape and size and made with the same type of dough. Instead of being cut in triangular slices, they are presented in thin strips, or "fingers".Instead of the traditional tomato sauce and toppings of a pizza, garlic fingers consist of pizza dough topped with garlic butter, parsley, and cheese, which is cooked until the cheese is melted. Bacon bits are also sometimes added.
Garlic fingers	Garlic fingers	Garlic fingers are often eaten as a side dish with pizza, and dipped in donair sauce or marinara sauce.
Garlic fingers	Wisconsin-style cheese fries	In central Wisconsin and some other parts of the state, a similar dish is served, consisting of a pizza-like, typically thin crust topped with cheese and garlic butter or a garlic-butter-like mixture. It is cut into strips and often accompanied with marinara sauce. Called cheese fries and sometimes pizza fries or Italian fries, they are sold both in restaurants and in the frozen foods section of supermarkets.
CART Precision Racing	CART Precision Racing	CART Precision Racing is a racing video game developed by Terminal Reality and published by Microsoft Studios for Windows.
CART Precision Racing	Development	The game was showcased at E3 1997.
CART Precision Racing	Reception	GameSpot said for the PC, "CART Precision Racing raises the bar for serious racing simulations" and rated the game 8.5. GamePro contradicted that "while Microsoft has done an admirable job with its new CART Precision Racing, it falls short of becoming the new benchmark in racing games." They elaborated that the "quirky controls", confusing array of menu screens, long loading times, and sound card compatibility issues keep the player from feeling fully comfortable while playing the game. They cited the detailed graphics and inclusion of real tracks, drivers, teams, and sponsors as strong points of the game.Next Generation rated it four stars out of five, and stated that "it's a very fun game and an impressive first effort".CART Precision Racing tied with Baseball Mogul to win Computer Gaming World's 1997 "Sports Game of the Year" award. The editors wrote: "With state-of-the-art graphics, Internet play, and incredibly deep options that scale the game from novice play through hard-core realism, CART offers the spiffiest high-tech sports thrills of the year".
Model-driven application	Model-driven application	A model-driven application is a software application that the functions or behaviors are based on, or in control of, some evolutionary applied models of the target things to the application. The applied models are served as a part of the application system in which it can be changed at runtime. The target things are what the application deals with, such as the objects and affairs in business for a business application. Follows the definition of application in TOGAF, a model-driven business application could be described as an IT system that supports business functions and services running on the models of the (things in) business.
Model-driven application	History	The ideal of the architecture for a model-driven application was first put forward by Tong-Ying Yu on the Enterprise Engineering Forum in 1999, which have been studied and spread through some internet media for a long time. It had influence on the field of enterprise application development in China; there were successful cases of commercial development of enterprise/business applications in the architectural style of a model-driven application. Gartner Group carried out some studies into the subject in 2008; they defined the model-driven packaged applications as "enterprise applications that have explicit metadata-driven models of the supported processes, data and relationships, and that generate runtime components through metadata models, either dynamically interpreted or compiled, rather than hardcoded." The model-driven application architecture is one of few technology trends to driven the next generation of application modernization, that claimed by some industrial researchers in 2012.
Model-driven application	Instance	Business process management (BPM) is the significant practice to the model-driven application. According to the definition, a BPM system is model-driven if the functions are operated based on the business process models which are built and changed at the operational time but not the design or implementation time; the biggest advantage is that it can deal with the continuous changing of business process directly without modifying the code of the software.
Model-driven application	Notes	Note that it should be distinguished from the Model-Driven Architecture (MDA); the latter is a software design approach for the development of software systems and generally does not specify a specific system style or the runtime configuration.
Seven-segment display character representations	Seven-segment display character representations	The topic of seven-segment display character representations revolves around the various shapes of numerical digits, letters, and punctuation devisable on seven-segment displays. Such representation of characters is not standardized by any relevant entity (e.g. ISO, IEEE or IEC). Unicode provides encoding codepoint for segmented digits in Unicode 13.0 in Symbols for Legacy Computing block.
Seven-segment display character representations	Digit	Two basic conventions are in common use for some Arabic numerals: display segment A is optional for digit 6 (/), segment F for 7 (/), and segment D for 9 (/). Although EF () could also be used to represent digit 1, this seems to be rarely done if ever. CDEG () is occasionally encountered on older calculators to represent 0.
Seven-segment display character representations	Digit	In Unicode 13.0, 10 codepoints had been given for segmented digits 0–9 in the Symbols for Legacy Computing block:
Seven-segment display character representations	Alphabet	In addition to the ten digits, seven-segment displays can be used to show most letters of the Latin, Cyrillic and Greek alphabets including punctuation.
Seven-segment display character representations	Alphabet	One such special case is the display of the letters A–F when denoting the hexadecimal values (digits) 10–15. These are needed on some scientific calculators, and are used with some testing displays on electronic equipment. Although there is no official standard, today most devices displaying hex digits use the unique forms shown to the right: uppercase A, lowercase b, uppercase C, lowercase d, uppercase E and F. To avoid ambiguity between the digit 6 and the letter b the digit 6 is displayed with segment A lit.However, this modern scheme was not always followed in the past, and various other schemes could be found as well: The Texas Instruments seven-segment display decoder chips 7446/7447/7448/7449 and 74246/74247/74248/74249 and the Siemens FLH551-7448/555-8448 chips used truncated versions of "2", "3", "4", "5" and "6" for digits A–G. Digit F (1111 binary) was blank.
Seven-segment display character representations	Alphabet	Soviet programmable calculators like the Б3-34 instead used the symbols "−", "L", "C", "Г", "E", and " " (space) to display hexadecimal numbers above nine. (The Б3-34 character set allowed for a cross-alphabet display of the English word "Error" as either EГГ0Г or 3ГГ0Г, depending on the error, in all-numeric form during error messages.) Not all 7-segment decoders were suitable to display digits above nine at all. For comparison, the National Semiconductor MM74C912 displayed "o" for A and B, "−" for C, D and E, F, and blank for G.
Seven-segment display character representations	Alphabet	The CD4511 even just displayed blanks.
Seven-segment display character representations	Alphabet	The Magic Black Box, an electronic version of the Magic 8-Ball toy, used a ROM to generate 64 different 16-character alphanumeric messages on a LED display. It could not generate K, M, V, W, and X but it could generate a question mark.For the remainder of characters, ad hoc and corporate solutions dominate the field of using seven-segment displays to show general words and phrases. Such applications of seven-segment displays are usually not considered essential and are only used for basic notifications on consumer electronics appliances (as is the case of this article's example phrases), and as internal test messages on equipment under development. Certain letters (M, V, W, X in the Latin alphabet) cannot be expressed unambiguously at all due to either diagonal strokes, more than two vertical strokes, or inability to distinguish them from other letters, while others can only be expressed in either capital form or lowercase form but not both. The Nine-segment display, fourteen-segment display, sixteen-segment display or dot matrix display are more commonly used for hardware that requires the display of messages that are more than trivial.
Seven-segment display character representations	Examples	The following phrases come from a portable media player's seven-segment display. They give a good illustration of an application where a seven-segment display may be sufficient for displaying letters, since the relevant messages are neither critical nor in any significant risk of being misunderstood, much due to the limited number and rigid domain specificity of the messages. As such, there is no direct need for a more expressive display, in this case, although even a slightly wider repertoire of messages would require at least a 14-segment display or a dot matrix one.
Memorex	Memorex	Memorex Corp. began as a computer tape producer and expanded to become both a consumer media supplier and a major IBM plug compatible peripheral supplier. It was broken up and ceased to exist after 1996 other than as a consumer electronics brand specializing in disk recordable media for CD and DVD drives, flash memory, computer accessories and other electronics.
Memorex	History and evolution	Established in 1961 in Silicon Valley, Memorex started by selling computer tapes, then added other media such as disk packs. The company then expanded into disk drives and other peripheral equipment for IBM mainframes. During the 1970s and into the early 1980s, Memorex was worldwide one of the largest independent suppliers of disk drives and communications controllers to users of IBM-compatible mainframes, as well as media for computer uses and consumers. The company's name is a portmanteau of "memory excellence".
Memorex	History and evolution	Memorex entered the consumer media business in 1971 and started the ad campaign, first with its "shattering glass" advertisements and then with a series of legendary television commercials featuring Ella Fitzgerald. In the commercials, she would sing a note that shattered a glass while being recorded to a Memorex audio cassette. The tape was played back and the recording also broke the glass, asking "Is it live, or is it Memorex?" This would become the company slogan which was used in a series of advertisements released through 1970s and 1980s.
Memorex	History and evolution	In 1982, Memorex was bought by Burroughs for its enterprise businesses; the company’s consumer business, a small segment of the company’s revenue at that time was sold to Tandy. Over the next six years, Burroughs and its successor Unisys shut down, sold off or spun out the various remaining parts of Memorex.
Memorex	History and evolution	The computer media, communications and IBM end user sales and service organization were spun out as Memorex International. In 1988, Memorex International acquired the Telex Corporation becoming Memorex Telex NV, a corporation based in the Netherlands, which survived as an entity until the middle 1990s. The company evolved into a provider of information technology solutions including the distribution and integration of data network and storage products and the provision of related services in 18 countries worldwide. As late as 2006, several pieces existed as subsidiaries of other companies, see e.g., Memorex Telex Japan Ltd a subsidiary of Kanematsu or Memorex Telex (UK) Ltd. a subsidiary of EDS Global Field Services.Over time the Memorex consumer brand has been owned by Tandy, Handy Holdings and Imation. As of 2016, the Memorex brand is owned by Digital Products International (DPI).
Memorex	Timeline	1961 – Memorex is founded by Laurence L. Spitters, Arnold T. Challman, Donald F. Eldridge and W Lawrence Noon with Spitters as president. 1962 – Memorex is one of the early independent companies to ship computer tape. May 1965 – Memorex IPO's at $25 and closes at $32. 1966 – Memorex is first independent company to ship a disk pack.
Memorex	Timeline	Jun 1968 – Memorex is first to ship an IBM-plug-compatible disk drive 1970 – Memorex ships 1270 Communications Controller 1971 – With CBS Memorex forms CMX Systems, a company formed to design videotape editing systems Sep 1971 – Memorex launches its consumer tape business 1972 – Memorex launches its "Is it live, or is it Memorex?" campaign Apr 1981 – Burroughs acquires Memorex Apr 1982 – Burroughs sells Memorex consumer brand to Tandy May 1985 – Burroughs exits OEM disk drive business, selling sales and service to Toshiba Sep 1986 – Burroughs acquires Sperry and renames itself as Unisys Dec 1986 – Unisys spins off Memorex Media, Telecommunications and International businesses as Memorex International NV.
Memorex	Timeline	Jan 1988 – Memorex-Telex merger Dec 1988 – Unisys mainly shuts down large disk business and spins off service and repair as Sequel. Nov 1993 – Tandy sells Memorex consumer brand to Hanny Holdings of Hong Kong Oct 1996 – The U.S. operations of Memorex Telex NV filed for bankruptcy and with court approval were sold November 1, 1996. Jan 2006 – Imation acquires Memorex brand for $330 million. Jan 2016 – Imation closed on the sale of its Memorex trademark and two associated trademark licenses to DPI Inc., a St. Louis-based branded consumer electronics company for $9.4 million.
FindBugs	FindBugs	FindBugs is an open-source static code analyser created by Bill Pugh and David Hovemeyer which detects possible bugs in Java programs. Potential errors are classified in four ranks: (i) scariest, (ii) scary, (iii) troubling and (iv) of concern. This is a hint to the developer about their possible impact or severity. FindBugs operates on Java bytecode, rather than source code. The software is distributed as a stand-alone GUI application. There are also plug-ins available for Eclipse, NetBeans, IntelliJ IDEA, Gradle, Hudson, Maven, Bamboo and Jenkins.Additional rule sets can be plugged in FindBugs to increase the set of checks performed.
FindBugs	SpotBugs	SpotBugs is the spiritual successor of FindBugs, carrying on from the point where it left off with support of its community.
FindBugs	SpotBugs	In 2016, the project lead of FindBugs was inactive but there are many issues in its community so Andrey Loskutov gave an announcement to its community, and some volunteers tried creating a project with support for modern Java platform and better maintainability. In 2017 Sep, Andrey Loskutov again gave an announcement about the status of new community, then released SpotBugs 3.1.0 with support for Java 11 the new LTS, especially Java Platform Module System and invokedynamic instruction.
FindBugs	SpotBugs	There are also plug-ins available for Eclipse, IntelliJ IDEA, Gradle, Maven and SonarQube. SpotBugs also supports all of existing FindBugs plugins such as sb-contrib, find-security-bugs, with several minor changes. Applications SpotBugs have numerous areas of applications: Testing during a Continuous Integration or Delivery Cycle. Locating faults in an application. During a code review.
International Journal of Neuroscience	International Journal of Neuroscience	The International Journal of Neuroscience is a peer-reviewed scientific journal that publishes original research articles, reviews, brief scientific notes, case studies, letters to the editor, and book reviews concerned with all aspects of neuroscience and neurology.
International Journal of Neuroscience	Editors	The Editors-in-Chief of the International Journal of Neuroscience is Dr. Mohamad Bydon.
Morphosyntactic alignment	Morphosyntactic alignment	In linguistics, morphosyntactic alignment is the grammatical relationship between arguments—specifically, between the two arguments (in English, subject and object) of transitive verbs like the dog chased the cat, and the single argument of intransitive verbs like the cat ran away. English has a subject, which merges the more active argument of transitive verbs with the argument of intransitive verbs, leaving the object distinct; other languages may have different strategies, or, rarely, make no distinction at all. Distinctions may be made morphologically (through case and agreement), syntactically (through word order), or both.
Morphosyntactic alignment	Terminology	Arguments Dixon (1994) The following notations will be used to discuss the various types of alignment: S (from sole), the subject of an intransitive verb ; A (from agent), the subject of a transitive verb; O (from object), the object of a transitive verb. Some authors use the label P (from patient) for O.Note that while the labels S, A, O, and P originally stood for subject, agent, object, and patient, respectively, the concepts of S, A, and O/P are distinct both from the grammatical relations and thematic relations. In other words, an A or S need not be an agent or subject, and an O need not be a patient.
Morphosyntactic alignment	Terminology	In a nominative–accusative system, S and A are grouped together, contrasting O. In an ergative–absolutive system, S and O are one group and contrast with A. The English language represents a typical nominative–accusative system (accusative for short). The name derived from the nominative and accusative cases. Basque is an ergative–absolutive system (or simply ergative). The name stemmed from the ergative and absolutive cases. S is said to align with either A (as in English) or O (as in Basque) when they take the same form.
Morphosyntactic alignment	Terminology	Bickel & Nichols (2009) Listed below are argument roles used by Bickel and Nichols for the description of alignment types. Their taxonomy is based on semantic roles and valency (the number of arguments controlled by a predicate).
Morphosyntactic alignment	Terminology	S, the sole argument of a one-place predicate A, the more agent-like arguments of a two-place (A1) or three-place (A2) predicate O, the less agent-like argument of a two-place predicate G, the more goal-like argument of a three-place predicate T, the non-goal-like and non-agent-like argument of a three-place predicate Locus of marking The term locus refers to a location where the morphosyntactic marker reflecting the syntactic relations is situated. The markers may be located on the head of a phrase, a dependent, and both or none of them.
Morphosyntactic alignment	Types of alignment	Nominative–accusative (or accusative) alignment treats the S argument of an intransitive verb like the A argument of transitive verbs, with the O argument distinct (S = A; O separate) (see nominative–accusative language). In a language with morphological case marking, an S and an A may both be unmarked or marked with the nominative case while the O is marked with an accusative case (or sometimes an oblique case used for dative or instrumental case roles also), as occurs with nominative -us and accusative -um in Latin: Julius venit "Julius came"; Julius Brutum vidit "Julius saw Brutus". Languages with nominative–accusative alignment can detransitivize transitive verbs by demoting the A argument and promoting the O to be an S (thus taking nominative case marking); it is called the passive voice. Most of the world's languages have accusative alignment. An uncommon subtype is called marked nominative. In such languages, the subject of a verb is marked for nominative case, but the object is unmarked, as are citation forms and objects of prepositions. Such alignments are clearly documented only in northeastern Africa, particularly in the Cushitic languages, and the southwestern United States and adjacent parts of Mexico, in the Yuman languages.
Morphosyntactic alignment	Types of alignment	Ergative–absolutive (or ergative) alignment treats an intransitive argument like a transitive O argument (S = O; A separate) (see ergative–absolutive language). An A may be marked with an ergative case (or sometimes an oblique case used also for the genitive or instrumental case roles) while the S argument of an intransitive verb and the O argument of a transitive verb are left unmarked or sometimes marked with an absolutive case. Ergative–absolutive languages can detransitivize transitive verbs by demoting the O and promoting the A to an S, thus taking the absolutive case, called the antipassive voice. About a sixth of the world's languages have ergative alignment. The best known are probably the Inuit languages and Basque.
Morphosyntactic alignment	Types of alignment	Active–stative alignment treats the arguments of intransitive verbs like the A argument of transitives (like English) in some cases and like transitive O arguments (like Inuit) in other cases (Sa=A; So=O). For example, in Georgian, Mariamma imğera "Mary (-ma) sang", Mariam shares the same narrative case ending as in the transitive clause Mariamma c'erili dac'era "Mary (-ma) wrote the letter (-i)", while in Mariami iq'o Tbilisši revolutsiamde "Mary (-i) was in Tbilisi up to the revolution", Mariam shares the same case ending (-i) as the object of the transitive clause. Thus, the arguments of intransitive verbs are not uniform in its behaviour. The reasons for treating intransitive arguments like A or like O usually have a semantic basis. The particular criteria vary from language to language and may be either fixed for each verb or chosen by the speaker according to the degree of volition, control, or suffering of the participant or to the degree of sympathy that the speaker has for the participant.
Morphosyntactic alignment	Types of alignment	Austronesian alignment, also called Philippine-type alignment, is found in the Austronesian languages of the Philippines, Borneo, Taiwan, and Madagascar. These languages have both accusative-type and ergative-type alignments in transitive verbs. They are traditionally (and misleadingly) called "active" and "passive" voice because the speaker can choose to use either one rather like active and passive voice in English. However, because they are not true voice, terms such as "agent trigger" or "actor focus" are increasingly used for the accusative type (S=A) and "patient trigger" or "undergoer focus" for the ergative type (S=O). (The terms with "trigger" may be preferred over those with "focus" because these are not focus systems either; morphological alignment has a long history of confused terminology). Patient-trigger alignment is the default in most of these languages. For either alignment, two core cases are used (unlike passive and antipassive voice, which have only one), but the same morphology is used for the "nominative" of the agent-trigger alignment and the "absolutive" of the patient-trigger alignment so there is a total of just three core cases: common S/A/O (usually called nominative, or less ambiguously direct), ergative A, and accusative O. Some Austronesianists argue that these languages have four alignments, with additional "voices" that mark a locative or benefactive with the direct case, but most maintain that these are not core arguments and thus not basic to the system.
Morphosyntactic alignment	Types of alignment	Direct alignment: very few languages make no distinction among agent, patient, and intransitive arguments, leaving the hearer to rely entirely on context and common sense to figure them out. This S/A/O case is called direct, as it sometimes is in Austronesian alignment. Tripartite alignment uses a separate case or syntax for each argument, which are conventionally called the accusative case, the intransitive case, and the ergative case. The Nez Perce language is a notable example.
Morphosyntactic alignment	Types of alignment	Transitive alignment: certain Iranian languages, such as Rushani, distinguish only transitivity (in the past tense), using a transitive case for both A and O, and an intransitive case for S. That is sometimes called a double-oblique system, as the transitive case is equivalent to the accusative in the non-past tense.The direct, tripartite, and transitive alignment types are all quite rare. The alignment types other than Austronesian and Active-Stative can be shown graphically like this: In addition, in some languages, both nominative–accusative and ergative–absolutive systems may be used, split between different grammatical contexts, called split ergativity. The split may sometimes be linked to animacy, as in many Australian Aboriginal languages, or to aspect, as in Hindustani and Mayan languages. A few Australian languages, such as Diyari, are split among accusative, ergative, and tripartite alignment, depending on animacy.
Morphosyntactic alignment	Types of alignment	A popular idea, introduced in Anderson (1976), is that some constructions universally favor accusative alignment while others are more flexible. In general, behavioral constructions (control, raising, relativization) are claimed to favor nominative–accusative alignment while coding constructions (especially case constructions) do not show any alignment preferences. This idea underlies early notions of ‘deep’ vs. ‘surface’ (or ‘syntactic’ vs. ‘morphological’) ergativity (e.g. Comrie 1978; Dixon 1994): many languages have surface ergativity only (ergative alignments only in their coding constructions, like case or agreement) but not in their behavioral constructions or at least not in all of them. Languages with deep ergativity (with ergative alignment in behavioral constructions) appear to be less common.
Morphosyntactic alignment	Comparison between ergative-absolutive and nominative-accusative	The arguments can be symbolized as follows: O = most patient-like argument of a transitive clause (also symbolized as P) S = sole argument of an intransitive clause A = most agent-like argument of a transitive clauseThe S/A/O terminology avoids the use of terms like "subject" and "object", which are not stable concepts from language to language. Moreover, it avoids the terms "agent" and "patient", which are semantic roles that do not correspond consistently to particular arguments. For instance, the A might be an experiencer or a source, semantically, not just an agent.
Morphosyntactic alignment	Comparison between ergative-absolutive and nominative-accusative	The relationship between ergative and accusative systems can be schematically represented as the following: The following Basque examples demonstrate ergative–absolutive case marking system: In Basque, gizona is "the man" and mutila is "the boy". In a sentence like mutila gizonak ikusi du, you know who is seeing whom because -k is added to the one doing the seeing. So the sentence means "the man saw the boy". If you want to say "the boy saw the man", add the -k instead to the word meaning "the boy": mutilak gizona ikusi du.
Morphosyntactic alignment	Comparison between ergative-absolutive and nominative-accusative	With a verb like etorri, "come", there's no need to distinguish "who is doing the coming", so no -k is added. "The boy came" is mutila etorri da.
Morphosyntactic alignment	Comparison between ergative-absolutive and nominative-accusative	Japanese – by contrast – marks nouns by following them with different particles which indicate their function in the sentence: In this language, in the sentence "the man saw the child", the one doing the seeing ("man") may be marked with ga, which works like Basque -k (and the one who is being seen may be marked with o). However, in sentences like "the child arrived" ga can still be used even though the situation involves only a "doer" and not a "done-to". This is unlike Basque, where -k is completely forbidden in such sentences.
Kempe's universality theorem	Kempe's universality theorem	In 1876 Alfred B. Kempe published his article On a General Method of describing Plane Curves of the nth degree by Linkwork, which showed that for an arbitrary algebraic plane curve a linkage can be constructed that draws the curve. This direct connection between linkages and algebraic curves has been named Kempe's universality theorem that any bounded subset of an algebraic curve may be traced out by the motion of one of the joints in a suitably chosen linkage. Kempe's proof was flawed and the first complete proof was provided in 2002 based on his ideas.This theorem has been popularized by describing it as saying, "One can design a linkage which will sign your name!"Kempe recognized that his results demonstrate the existence of a drawing linkage but it would not be practical. He states It is hardly necessary to add, that this method would not be practically useful on account of the complexity of the linkwork employed, a necessary consequence of the perfect generality of the demonstration.
Kempe's universality theorem	Kempe's universality theorem	He then calls for the "mathematical artist" to find simpler ways to achieve this result: The method has, however, an interest, as showing that there is a way of drawing any given case; and the variety of methods of expressing particular functions that have already been discovered renders it in the highest degree probable that in every case a simpler method can be found. There is still, however, a wide field open to the mathematical artist to discover the simplest linkworks that will describe particular curves.
Kempe's universality theorem	Kempe's universality theorem	A series of animations demonstrating the linkwork that results from Kempe's universality theorem are available for the parabola, self-intersecting cubic, smooth elliptic cubic and the trifolium curves.
Kempe's universality theorem	Simpler drawing linkages	Several approaches have been taken to simplify the drawing linkages that result from Kempe's universality theorem. Some of the complexity arises from the linkages Kempe used to perform addition and subtraction of two angles, the multiplication of an angle by a constant, and translation of the rotation of a link in one location to a rotation of a second link at another location. Kempe called these linkages additor, reversor, multiplicator and translator linkages, respectively. The drawing linkage can be simplified by using bevel gear differentials to add and subtract angles, gear trains to multiply angles and belt or cable drives to translate rotation angles.Another source of complexity is the generality of Kempe's application to all algebraic curves. By focusing on parameterized algebraic curves, dual quaternion algebra can be used to factor the motion polynomial and obtain a drawing linkage. This has been extended to provide movement of the end-effector, but again for parameterized curves.Specializing the curves to those defined by trigonometric polynomials has provided another way to obtain simpler drawing linkages. Bezier curves can be written in the form of trigonometric polynomials therefore a linkage system can be designed that draws any curve that is approximated by a sequence of Bezier curves.
Kempe's universality theorem	Visualizations	Below is an example of a single-coupled serial chain mechanism, designed by Liu and McCarthy, used to draw the trifolium curve (left) and the hypocycloid curve (right). Using SageMath, their design was interpreted into these images. The source code can be found on GitHub.
Ynolate	Ynolate	Ynolates are chemical compounds with a negatively charged oxygen attached to an alkyne functionality. They were first synthesized in 1975 by Schöllkopf and Hoppe via the n-butyllithium fragmentation of 3,4-diphenylisoxazole.Synthetically, they behave as ketene precursors or synthons.
Unisys OS 2200 programming languages	Unisys OS 2200 programming languages	OS 2200 has had several generations of compilers and linkers in its history supporting a wide variety of programming languages. In the first releases, the Exec II assembler (SLEUTH) and compilers were used. The assembler was quickly replaced with an updated version (ASM) designed specifically for the 1108 computer and Exec 8 but the early compilers continued in use for quite some time.
Unisys OS 2200 programming languages	Universal Compiling System	The modern compiling system for OS 2200 is known as UCS, Universal Compiling System. The UCS architecture uses a common syntax analyzer, separate semantic front ends for each language and a common back-end and optimizer. There is also a common language runtime environment. The UCS system was developed starting in 1969 and initially included PL/I and Pascal. FORTRAN and COBOL were soon added. Ada was added later. The currently supported languages include COBOL, FORTRAN, C, and PLUS. PLUS, Programming Language for Unisys (originally UNIVAC) Systems, is a block structured language somewhat similar to Pascal which it predates.
Unisys OS 2200 programming languages	Legacy compilers	Previous PLUS, COBOL and FORTRAN compilers are also still supported. An even earlier FORTRAN compiler (FORTRAN V), while no longer supported, is still in use for an application developed in the 1960s in that language. Compilers previously existed for ALGOL, Simula, BASIC, Lisp, NELIAC, JOVIAL, and other programming languages that are no longer in use on the ClearPath OS 2200 systems.
Unisys OS 2200 programming languages	Assembler	The assembler, MASM, is heavily used both to obtain the ultimate in efficiency and to implement system calls that are not native to the programming language. Much of the MASM code in current use is a carryover from earlier days when compiler technology was not as advanced and when the machines were much slower and more constrained by memory size than today.
Unisys OS 2200 programming languages	Linking	There are two linking systems used. The collector (@MAP) combines the output relocatable elements of the basic-mode compilers and assemblers into an absolute element which is directly executable. While this linker is intended primarily to support basic mode, the relocatable and absolute elements may contain extended-mode as well. This is often the case when an existing application is enhanced to use extended mode or call extended mode libraries but still contains some basic mode code. The Exec is an example of such a program.
Unisys OS 2200 programming languages	Linking	The linker (@LINK) is the modern linking environment which combines object modules into a new object module. It provides both static and dynamic linking capabilities. The most common usage is to combine the object modules of a program statically but to allow dynamic linking to libraries.
Unisys OS 2200 programming languages	Java	OS 2200 provides a complete Java environment.
Unisys OS 2200 programming languages	Java	Java on OS 2200 has evolved from an interesting additional capability for small servlets and tools to a full environment capable of handling large applications. The Virtual Machine for the Java Platform on ClearPath OS 2200 JProcessor is a Linux port of the Oracle Corporation Java release. The environment includes a full J2EE application server environment using the Tomcat open source web server from the Apache Software Foundation and the JBoss application server. All of this has been integrated with the OS 2200 security, databases, and recovery environment.
Ancient TL	Ancient TL	Ancient TL is a peer-reviewed open-access scientific journal covering luminescence and electron spin resonance dating. It is published by the Luminescence Dosimetry Laboratory, Department of Physics, East Carolina University. The journal was established in 1977 by D.W. Zimmerman (Washington University in St. Louis). Since 2015 the journal has been available online only. The journal is community maintained and articles can be published and downloaded free of charge. Since 2020, articles are published under the Creative Commons licence CC BY 4.0.
Isotopes of gadolinium	Isotopes of gadolinium	Naturally occurring gadolinium (64Gd) is composed of 6 stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd, and 1 radioisotope, 152Gd, with 158Gd being the most abundant (24.84% natural abundance). The predicted double beta decay of 160Gd has never been observed; only a lower limit on its half-life of more than 1.3×1021 years has been set experimentally.Thirty-three radioisotopes have been characterized, with the most stable being alpha-decaying 152Gd (naturally occurring) with a half-life of 1.08×1014 years, and 150Gd with a half-life of 1.79×106 years. All of the remaining radioactive isotopes have half-lives less than 74.7 years. The majority of these have half-lives less than 24.6 seconds. Gadolinium isotopes have 10 metastable isomers, with the most stable being 143mGd (t1/2 = 110 seconds), 145mGd (t1/2 = 85 seconds) and 141mGd (t1/2 = 24.5 seconds).
Isotopes of gadolinium	Isotopes of gadolinium	The primary decay mode at atomic weights lower than the most abundant stable isotope, 158Gd, is electron capture, and the primary mode at higher atomic weights is beta decay. The primary decay products for isotopes lighter than 158Gd are isotopes of europium and the primary products of heavier isotopes are isotopes of terbium.
Isotopes of gadolinium	Isotopes of gadolinium	Gadolinium-153 has a half-life of 240.4 ± 10 days and emits gamma radiation with strong peaks at 41 keV and 102 keV. It is used as a gamma ray source for X-ray absorptiometry and fluorescence, for bone density gauges for osteoporosis screening, and for radiometric profiling in the Lixiscope portable x-ray imaging system, also known as the Lixi Profiler. In nuclear medicine, it serves to calibrate the equipment needed like single-photon emission computed tomography systems (SPECT) to make x-rays. It ensures that the machines work correctly to produce images of radioisotope distribution inside the patient. This isotope is produced in a nuclear reactor from europium or enriched gadolinium. It can also detect the loss of calcium in the hip and back bones, allowing the ability to diagnose osteoporosis.Gadolinium-148 would be ideal for radioisotope thermoelectric generators due to its 74-year half-life, high density, and dominant alpha decay mode. However, gadolinium-148 cannot be economically synthesized in sufficient quantities to power a RTG.
Shell growth in estuaries	Shell growth in estuaries	Shell growth in estuaries is an aspect of marine biology that has attracted a number of scientific research studies. Many groups of marine organisms produce calcified exoskeletons, commonly known as shells, hard calcium carbonate structures which the organisms rely on for various specialized structural and defensive purposes. The rate at which these shells form is greatly influenced by physical and chemical characteristics of the water in which these organisms live. Estuaries are dynamic habitats which expose their inhabitants to a wide array of rapidly changing physical conditions, exaggerating the differences in physical and chemical properties of the water.
Shell growth in estuaries	Shell growth in estuaries	Estuaries have large variation in salinity, ranging from entirely fresh water upstream to fully marine water at the ocean boundary. Estuarine systems also experience daily, tidal and seasonal swings in temperature, which affect many of the chemical characteristics of the water and in turn affect the metabolic and calcifying processes of shell-producing organisms. Temperature and salinity affect the carbonate balance of the water, influencing carbonate equilibrium, calcium carbonate solubility and the saturation states of calcite and aragonite. The tidal influences and shallow water of estuaries mean that estuarine organisms experience wide variations in temperature, salinity and other aspects of water chemistry; these fluctuations make the estuarine habitat ideal for studies on the influence of changing physical and chemical conditions on processes such as shell deposition. Changing conditions in estuaries and coastal regions are especially relevant to human interests, because about 50% of global calcification and 90% of fish catch occurs in these locations.A substantial proportion of larger marine calcifying organisms are molluscs: bivalves, gastropods and chitons. Cnidarians such as corals, echinoderms such as sea urchins, and arthropods such as barnacles also produce shells in coastal ecosystems. Most of these groups are benthic, living on hard or soft substrates at the bottom of the estuary. Some are attached, like barnacles or corals; some move around on the surface like urchins or gastropods; and some live inside the sediment, like most of the bivalve species.
Shell growth in estuaries	Shell growth in estuaries	Minute pelagic species in the phyla Foraminifera and Radiolaria also produce ornate calcareous skeletons. Many benthic mollusks have planktonic larvae called veligers that have calcareous shells, and these larvae are particularly vulnerable to changes in water chemistry; their shells are so thin that small changes in pH can have a large impact on their ability to survive. Some holoplankton (organisms that are planktonic for their full lives) have calcareous skeletons as well, and are even more susceptible to unfavorable shell deposition conditions, since they spend their entire lives in the water column.
Shell growth in estuaries	Details of carbonate usage	There are several variations in calcium carbonate (CaCO3) skeletons, including the two different crystalline forms, calcite and aragonite, as well as other elements which can become incorporated into the mineral matrix, altering its properties. Calcite is a hexagonal form of CaCO3 that is softer and less dense than aragonite, which has a rhombic form. Calcite is the more stable form of CaCO3 and is less soluble in water under standard temperature and pressure than aragonite, with a solubility product constant (Ksp) of 10−8.48 compared to 10−8.28 for aragonite. This means that a greater proportion of aragonite will dissolve in water, producing calcium (Ca2+) and carbonate (CO32−) ions. The amount of magnesium (Mg) incorporated into the mineral matrix during calcium carbonate deposition can also alter the properties of the shell, because magnesium inhibits calcium deposition by inhibiting nucleation of calcite and aragonite. Skeletons with significant amounts of magnesium incorporated into the matrix (greater than 12%) are more soluble, so the presence of this mineral can negatively impact shell durability, which is why some organisms remove magnesium from the water during the calcification process.
Shell growth in estuaries	Influencing factors	Food availability can alter shell growth patterns, as can chemical cues from predators, which cause clams, snails and oysters to produce thicker shells. There are costs to producing thicker shells as protection, including the energetic expense of calcification, limits on somatic growth, and reduced growth rates in terms of shell length. In order to minimize the significant energetic expense of shell formation, several calcifying species reduce shell production by producing porous shells or spines and ridges as more economical forms of predator defense.
Shell growth in estuaries	Influencing factors	Temperature and salinity also affect shell growth by altering organismal processes, including metabolism and shell magnesium (Mg) incorporation, as well as water chemistry in terms of calcium carbonate solubility, CaCO3 saturation states, ion-pairing, alkalinity and carbonate equilibrium. This is especially relevant in estuaries, where salinities range from 0 to 35, and other water properties such as temperature and nutrient composition also vary widely during the transition from fresh river water to saline ocean water. Acidity (pH) and carbonate saturation states also reach extremes in estuarine systems, making these habitats a natural testing ground for the impacts of chemical changes on the calcification of shelled organisms.
Shell growth in estuaries	Carbonate and shell deposition	Calcification rates are largely related to the amount of available carbonate (CO32−) ions in the water, and this is linked to the relative amounts of (and reactions between) different types of carbonate. Carbon dioxide from the atmosphere and from respiration of animals in estuarine and marine environments quickly reacts in water to form carbonic acid, H2CO3. Carbonic acid then dissociates into bicarbonate (HCO3−) and releases hydrogen ions, and the equilibrium constant for this equation is referred to as K1. Bicarbonate dissociates into carbonate (CO32−), releasing another hydrogen ion (H+), with an equilibrium constant known as K2. The equilibrium constants refer to the ratio of products to reactants produced in these reactions, so the constants K1 and K2 govern the relative amounts of different carbonate compounds in the water.
Shell growth in estuaries	Carbonate and shell deposition	H2CO3 ↔ H+ + HCO3− K1 = ([H+] x [HCO3−]) / [H2CO3] HCO3− ↔ H+ + CO32− K2 = ([H+] x [CO32−]) / [HCO3−] Since alkalinity, or acid-buffering capacity, of the water is regulated by the number of hydrogen ions that a cation can accept, carbonate (can accept 2 H+) and bicarbonate (can accept 1 H+) are the principal components of alkalinity in estuarine and marine systems. Since acidic conditions promote shell dissolution, the alkalinity of the water is positively correlated with shell deposition, especially in estuarine regions that experience broad swings in pH. Based on the carbonate equilibrium equations, an increase in K2 leads to higher levels of available carbonate and a potential increase in calcification rates as a result. The values for K1 and K2 can be influenced by several different physical factors, including temperature, salinity and pressure, so organisms in different habitats can encounter different equilibrium conditions. Many of these same factors influence solubility of calcium carbonate, with the solubility product constant Ksp expressed as the concentration of dissolved calcium and carbonate ions at equilibrium: Ksp = [Ca2+][CO32−]. Therefore, increases in Ksp based on differences in temperature or pressure or increases in the apparent solubility constant K’sp as a result of salinity or pH changes means that calcium carbonate is more soluble. Increased solubility of CaCO3 makes shell deposition more difficult, and so this has a negative impact on the calcification process.
Shell growth in estuaries	Carbonate and shell deposition	The saturation state of calcium carbonate also has a strong influence on shell deposition, with calcification only occurring when the water is saturated or supersaturated with CaCO3, based on the formula: Ω = [CO32−][Ca2+] / K’sp. Higher saturation states mean higher concentrations of carbonate and calcium relative to the solubility of calcium carbonate, favoring shell deposition. The two forms of CaCO3 have different saturation states, with the more soluble aragonite displaying a lower saturation state than calcite. Since aragonite is more soluble than calcite and solubility increases with pressure, the depth at which the ocean is undersaturated with aragonite (aragonite compensation depth) is shallower than the depth at which it is undersaturated with calcite (calcite compensation depth). As a result, aragonite-based organisms live in shallower environments. Calcification rate does not change much with saturation levels above 300%. Since saturation state can be affected by both solubility and carbonate ion concentrations, it can be strongly impacted by environmental factors such as temperature and salinity.
Shell growth in estuaries	Effect of temperature on calcification	Water temperatures vary widely on a seasonal basis in polar and temperate habitats, inducing metabolic changes in organisms exposed to these conditions. Seasonal temperature swings are even more drastic in estuaries than in the open ocean due to the large surface area of shallow water as well as the differential temperature of ocean and river water. During the summer, rivers are often warmer than the ocean, so there is a gradient of decreasing temperature towards the ocean in an estuary. This switches in the winter, with ocean waters being much warmer than river water, producing the opposite temperature gradient. Temperature is changing on a larger time scale as well, with predicted temperature changes slowly increasing both freshwater and marine water sources (though at variable rates), further enhancing the impact that temperature has on shell deposition processes in estuarine environments.
Shell growth in estuaries	Effect of temperature on calcification	Solubility product Temperature has a strong effect on the solubility product constants for both calcite and aragonite, with an approximately 20% decrease in K’sp from 0 to 25 °C. The lower solubility constants for calcite and aragonite with elevated temperature have a positive impact on calcium carbonate precipitation and deposition, making it easier for calcifying organisms to produce shells in water with lower solubility of calcium carbonate. Temperature can also influence the calcite:aragonite ratios, as aragonite precipitation rates are more strongly tied to temperature, with aragonite precipitation dominating above 6 °C.
Shell growth in estuaries	Effect of temperature on calcification	Saturation state Temperature also has a large impact on the saturation state of calcium carbonate species, as the level of disequilibrium (degree of saturation) strongly influences reaction rates. Comeau et al. point out that cold locations such as the Arctic show the most dramatic decreases in aragonite saturation state (Ω) associated with climate change. This particularly affects pteropods since they have thin aragonite shells and are the dominant planktonic species in cold Arctic waters. There is a positive correlation between temperature and calcite saturation state for the eastern oyster Crassostrea virginica, which produces a shell primarily composed of calcite. While oysters are benthic and use calcite instead of aragonite (like pteropods), there is still a clear increase in both calcite saturation level and oyster calcification rate at the higher temperature treatments.
Shell growth in estuaries	Effect of temperature on calcification	In addition to impacting the solubility and saturation state of calcite and aragonite, temperature can alter the composition of shell or calcified skeletons, especially influencing the incorporation of magnesium (Mg) into the mineral matrix. Magnesium content of carbonate skeletons (as MgCO3) increases with temperature, explaining a third of the variation in sea star Mg:Ca ratios. This is important because when more than 8-12% of a calcite-dominated skeleton is composed of MgCO3, the shell material is more soluble than aragonite. As a result of the positive correlation between temperature and Mg content, organisms that live in colder environments such as the deep sea and high latitudes have a lower percentage of MgCO3 incorporated into their shells.
Shell growth in estuaries	Effect of temperature on calcification	Even small temperature changes such as those predicted under global warming scenarios can influence Mg:Ca ratios, as the foraminiferan Ammonia tepida increases its Mg:Ca ratio 4-5% per degree of temperature elevation. This response is not limited to animals or open ocean species, since crustose coralline algae also increase their incorporation of magnesium and therefore their solubility at elevated temperatures.
Shell growth in estuaries	Effect of temperature on calcification	Shell deposition Between the effect that temperature has on Mg:Ca ratios as well as on solubility and saturation state of calcite and aragonite, it is clear that short- or long-term temperature variations can influence the deposition of calcium carbonate by altering seawater chemistry. The impact that these temperature-induced chemical changes have on shell deposition has been repeatedly demonstrated for a wide array of organisms that inhabit estuarine and coastal systems, highlighting the cumulative effect of all temperature-influenced factors.
Shell growth in estuaries	Effect of temperature on calcification	The blue mussel Mytilus edulis is a major space occupier on hard substrates on the east coast of North America and west coast of Europe, and the calcification rate of this species increases up to five times with rising temperature. Eastern oysters and crustose coralline algae have also been shown to increase their calcification rates with elevated temperature, though this can have varied effects on the morphology of the organism.Schone et al. (2006) found that the barnacle Chthamalus fissus and mussel Mytella guyanensis showed faster shell elongation rates at higher temperature, with over 50% of this variability in shell growth explained by temperature changes. The cowry (a sea snail) Monetaria annulus displayed a positive correlation between sea surface temperature (SST) and the thickness of the callus, the outer surface of juvenile shells.
Shell growth in estuaries	Effect of temperature on calcification	The predatory intertidal snail Nucella lapillus also develops thicker shells in warmer climates, likely due to constraints on calcification in cold water. Bivalve clams show higher growth rates and produce thicker shells, more spines, and more shell ornamentation at warmer, low latitude locations, again highlighting the enhancement of calcification as a result of warmer water and the corresponding chemical changes.The short-term changes in calcification rate and shell growth described by the aforementioned studies are based on experimental temperature elevation or latitudinal thermal gradients, but long-term temperature trends can also affect shell growth. Sclerochronology can reconstruct historical temperature data from growth increments in shells of many calcifying organisms based on differential growth rates at different temperatures. The visible markers for these growth increments are similar to growth rings, and are also present in fossil shells, enabling researchers to establish that clams such as Phacosoma balticum and Ruditapes philippinarum grew the fastest during times of warmer climate.
Shell growth in estuaries	Effect of salinity on calcification	Salinity refers to the water's "saltiness". In oceanography and marine biology, it has been traditional to express salinity not as a percent, but as permille (parts per thousand) (‰), which is approximately grams of salt per kilogram of solution. Salinity varies even more widely than temperature in estuaries, ranging from zero to 35, often over relatively short distances. Even organisms in the same location experience broad swings in salinity with the tides, exposing them to very different water masses with chemical properties that provide varying levels of support for calcification processes. Even within a single estuary, an individual species can be exposed to differing shell deposition conditions, resulting in varied growth patterns due to changes in water chemistry and resultant calcification rates.
Shell growth in estuaries	Effect of salinity on calcification	Magnesium:calcium ratios Salinity displays a positive correlation with magnesium:calcium (Mg:Ca) ratios, though shows only about half as much influence as temperature. Salinity in some systems can account for about 25% of the variation in Mg:Ca ratios, with 32% explained by temperature, but these salinity induced changes in shell MgCO3 incorporation are not due to differences in available magnesium. Instead, in planktonic foraminiferans, changes in salinity could hinder the internal mechanisms of magnesium removal prior to calcification. Foraminiferans are thought to produce calcification vacuoles that transport pockets of seawater to the calcification site and alter the makeup of the seawater and remove magnesium, a process that may be interrupted by high levels of salinity. Salinity can also affect the solubility of CaCO3, as shown by the following formulas relating temperature (T) and salinity (S) to K’sp, the apparent solubility product constant for CaCO3.K’sp(calcite) = (0.1614 + .05225 S – 0.0063 T) x 10−6K’sp(aragonite) = (0.5115 + .05225 S – 0.0063 T) x 10−6These equations show that temperature displays a negative relationship with K’sp, while salinity shows a positive relationship with K’sp (calcite and aragonite). The slopes of these lines are the same, with only the intercept changing for the different carbonate species, highlighting that at standard temperature and pressure, aragonite is more soluble than calcite. Mucci presented more complex equations relating temperature and salinity to K’sp, but the same general pattern appears.The increasing solubility of CaCO3 with salinity indicates that organisms in more marine environments would have difficulty depositing shell material if this factor was the only one influencing shell formation. Apparent solubility product is tied to salinity because of the ionic strength of the solution and the formation of cation-carbonate ion pairs that lower the amount of carbonate ions that are available in the water. This equates to the removal of the products from the equation for the dissolution of CaCO3 in water (CaCO3 ↔ Ca2+ + CO32−), which facilitates the forward reaction and favors the dissolution of calcium carbonate. This results in an apparent solubility product for CaCO3 that is 193 times higher in 35‰ seawater than in distilled water.
Shell growth in estuaries	Effect of salinity on calcification	Saturation state Salinity has a different effect on the saturation state of calcite and aragonite, causing increases in these values and in calcium concentrations with higher salinity, favoring the precipitation of calcium carbonate. Both alkalinity, or acid buffering capacity, and CaCO3 saturation state increase with salinity, which may help estuarine organisms to overcome fluctuations in pH that could otherwise negatively impact shell formation. However, river waters in some estuaries are oversaturated with calcium carbonate, while mixed estuarine water is undersaturated due to low pH resulting from respiration. Highly eutrophic estuaries support high amounts of planktonic and benthic animals that consume oxygen and produce carbon dioxide, which lowers the pH of estuarine waters and the amount of free carbonate. Therefore, even though higher salinity can cause increased saturation states of calcite and aragonite, there are many other factors that interact in this system to influence the shell deposition of estuarine organisms.
Shell growth in estuaries	Effect of salinity on calcification	Shell deposition All of these aspects of shell deposition are affected by salinity in different ways, so it is useful to examine the overall impact that salinity has on calcification rates and shell formation in estuarine organisms, especially in conjunction with temperature, which also affects calcification. Fish bones and scales are heavily calcified, and these parts of Arctic fish are about half as calcified (27% inorganic material) as those from fish in temperate (33%) and tropical (50%) environments. The benthic blue mussel Mytilus edulis also displayed an increase in calcification rate with salinity, showing calcification rates up to 5 times higher at 37‰ than 15‰.For oysters in Chesapeake Bay, salinity does not have an influence on calcification at high temperature (30 °C), but does significantly increase calcification at cooler temperature (20 °C). In the crustose coralline algae Phymatolithon calcareum, temperature and salinity showed an additive effect, as both of these factors increased the overall calcification rate of this encrusting alga. The gross effect of salinity on calcification is largely a positive one, as evidenced by the positive impact of salinity on calcification rates in diverse groups of species. This is likely a result of the increased alkalinity and calcium carbonate saturation states with salinity, which combine to decrease free hydrogen ions and increase free carbonate ions in the water. Higher alkalinity in marine waters is especially important since carbon dioxide produced via respiration in estuaries can lower pH, which decreases saturation states of calcite and aragonite and can cause CaCO3 dissolution. Because of lower salinity in fresher parts of estuaries, alkalinity is lower, increasing the susceptibility of estuarine organisms to calcium carbonate dissolution due to low pH. Increases in salinity and temperature can counteract the negative impact of pH on calcification rates, as they elevate calcite and aragonite saturation states and generally facilitate more favorable conditions for shell growth.
Shell growth in estuaries	Future changes	Shell growth and calcification rate are the cumulative outcome of the impacts of temperature and salinity on water chemistry and organismal processes such as metabolism and respiration. It has been established that temperature and salinity influence the balance of the carbonate equilibrium, the solubility and saturation state of calcite and aragonite, as well as the amount of magnesium that gets incorporated into the mineral matrix of the shell. All of these factors combine to produce net calcification rates that are observed under different physical and environmental conditions. Organisms from many phyla produce calcium carbonate skeletons, so organismal processes vary widely, but the effect of physical conditions on water chemistry impacts all calcifying organisms. Since these conditions are dynamic in estuaries, they serve as an ideal test environment to draw conclusions about future shifts in calcification rates based on changes in water chemistry with climate change.
Shell growth in estuaries	Future changes	Climate change With changing climate, precipitation is predicted to increase in many areas, resulting in higher river discharge into estuarine environments. In large estuaries such as the Chesapeake Bay, this could result in a large-scale decrease in salinity over hundreds of square kilometers of habitats and cause a decrease in alkalinity and CaCO3 saturation states, reducing calcification rates in affected habitats. Lower alkalinity and increased nutrient availability from runoff will increase biological activity, producing carbon dioxide and thus lowering the pH of these environments. This could be exacerbated by pollution that could make estuarine environments even more eutrophic, negatively impacting shell growth since more acidic conditions favor shell dissolution. However, this may be mitigated by increased temperature due to global warming, since elevated temperature result in lower solubility and higher saturation states for calcite and aragonite, facilitating CaCO3 precipitation and shell formation. Therefore, if organisms are able to adapt or acclimate to increased temperature in terms of physiology, the higher temperature water will be more conducive to shell production than current water temperature, at least in temperate regions.
Shell growth in estuaries	Future changes	Calcification rates The limiting factor in shell deposition may be saturation state, especially for aragonite, which is a more soluble and less stable form of CaCO3 than calcite. In 1998, the average global aragonite saturation state was 390%, a range commonly experienced since the last glacial period and a percentage above which calcification rates plateaued. However, there is a precipitous drop in calcification rate with aragonite saturation state dropping below 380%, with a three-fold decrease in calcification accompanying a drop to 98% saturation. By 2100, pCO2 of 560 and pH drop to 7.93 (global ocean average) will reduce the saturation state to 293%, which is unlikely to cause calcification decreases. The following 100–200 years may see pCO2 increase to 1000, pH drop to 7.71, and aragonite saturation state drop to 192, which would result in a 14% drop in calcification rate based on this alone. This could be exacerbated by low salinity from higher precipitation in estuaries, but could also be mitigated by increased temperature which could increase calcification rates. The interaction between pH, temperature and salinity in estuaries and in the world ocean will drive calcification rates and determine future species assemblages based on susceptibility to this change.
Shell growth in estuaries	Future changes	One problem with counting on increased temperature to counteract effects of acidification on calcification rate is the relationship between temperature and Mg:Ca ratios, as higher temperature result in higher amounts of magnesium incorporated into the shell matrix. Shells with higher Mg:Ca ratios are more soluble, so even organisms with primarily calcite (less soluble than aragonite) skeletons may be heavily impacted by future conditions.
Connectivism	Connectivism	Connectivism is a theoretical framework for understanding learning in a digital age. It emphasizes how internet technologies such as web browsers, search engines, wikis, online discussion forums, and social networks contributed to new avenues of learning. Technologies have enabled people to learn and share information across the World Wide Web and among themselves in ways that were not possible before the digital age. Learning does not simply happen within an individual, but within and across the networks. What sets connectivism apart from theories such as constructivism is the view that "learning (defined as actionable knowledge) can reside outside of ourselves (within an organization or a database), is focused on connecting specialized information sets, and the connections that enable us to learn more are more important than our current state of knowing". Connectivism sees knowledge as a network and learning as a process of pattern recognition. Connectivism has similarities with Vygotsky's zone of proximal development (ZPD) and Engeström's activity theory. The phrase "a learning theory for the digital age" indicates the emphasis that connectivism gives to technology's effect on how people live, communicate, and learn. Connectivism is an integration of principles related to chaos, network, complexity, and self-organization theories.
Connectivism	History	Connectivism was first introduced in 2004 on a blog post which was later published as an article in 2005 by George Siemens. It was later expanded in 2005 by two publications, Siemens' Connectivism: Learning as Network Creation and Downes' An Introduction to Connective Knowledge. Both works received significant attention in the blogosphere and an extended discourse has followed on the appropriateness of connectivism as a learning theory for the digital age. In 2007, Bill Kerr entered into the debate with a series of lectures and talks on the matter, as did Forster, both at the Online Connectivism Conference at the University of Manitoba. In 2008, in the context of digital and e-learning, connectivism was reconsidered and its technological implications were discussed by Siemens' and Ally.
Connectivism	Nodes and links	The central aspect of connectivism is the metaphor of a network with nodes and connections. In this metaphor, a node is anything that can be connected to another node such as an organization, information, data, feelings, and images. Connectivism recognizes three node types: neural, conceptual (internal) and external. Connectivism sees learning as the process of creating connections and expanding or increasing network complexity. Connections may have different directions and strength. In this sense, a connection joining nodes A and B which goes from A to B is not the same as one that goes from B to A. There are some special kinds of connections such as "self-join" and pattern. A self-join connection joins a node to itself and a pattern can be defined as "a set of connections appearing together as a single whole".The idea of organisation as cognitive systems where knowledge is distributed across nodes originated from the Perceptron (Artificial neuron) in an Artificial Neural Network, and is directly borrowed from Connectionism, "a software structure developed based on concepts inspired by biological functions of brain; it aims at creating machines able to learn like human".The network metaphor allows a notion of "know-where" (the understanding of where to find the knowledge when it is needed) to supplement to the ones of "know-how" and "know-what" that make the cornerstones of many theories of learning.
Connectivism	Nodes and links	As Downes states: "at its heart, connectivism is the thesis that knowledge is distributed across a network of connections, and therefore that learning consists of the ability to construct and traverse those networks". Principles Principles of connectivism include: Learning and knowledge rests in diversity of opinions. Learning is a process of connecting specialized nodes or information sources. Learning may reside in non-human appliances. Learning is more critical than knowing. Maintaining and nurturing connections is needed to facilitate continuous learning. When the interaction time between the actors of a learning environment is not enough, the learning networks cannot be consolidated. Perceiving connections between fields, ideas and concepts is a core skill. Currency (accurate, up-to-date knowledge) is the intent of learning activities. Decision-making is itself a learning process. Choosing what to learn and the meaning of incoming information is seen through the lens of a shifting reality. While there is a right answer now, it may be wrong tomorrow due to alterations in the information climate affecting the decision.
Connectivism	Teaching methods	Summarizing connectivist teaching and learning, Downes states: "to teach is to model and demonstrate, to learn is to practice and reflect."In 2008, Siemens and Downes delivered an online course called "Connectivism and Connective Knowledge". It covered connectivism as content while attempting to implement some of their ideas. The course was free to anyone who wished to participate, and over 2000 people worldwide enrolled. The phrase "Massive Open Online Course" (MOOC) describes this model. All course content was available through RSS feeds, and learners could participate with their choice of tools: threaded discussions in Moodle, blog posts, Second Life and synchronous online meetings. The course was repeated in 2009 and in 2011.
Connectivism	Teaching methods	At its core, connectivism is a form of experiential learning which prioritizes the set of formed by actions and experience over the idea that knowledge is propositional.
Connectivism	Criticisms	The idea that connectivism is a new theory of learning is not widely accepted. Verhagen argued that connectivism is rather a "pedagogical view."The lack of comparative literature reviews in Connectivism papers complicate evaluating how Connectivism relates to prior theories, such as socially distributed cognition (Hutchins, 1995), which explored how connectionist ideas could be applied to social systems. Classical theories of cognition such as activity theory (Vygotsky, Leont'ev, Luria, and others starting in the 1920s) proposed that people are embedded actors, with learning considered via three features – a subject (the learner), an object (the task or activity) and tool or mediating artifacts. Social cognitive theory (Bandura, 1962) claimed that people learn by watching others. Social learning theory (Miller and Dollard) elaborated this notion. Situated cognition (Brown, Collins, & Duguid, 1989; Greeno & Moore, 1993) alleged that knowledge is situated in activity bound to social, cultural and physical contexts; knowledge and learning that requires thinking on the fly rather than the storage and retrieval of conceptual knowledge. Community of practice (Lave & Wenger 1991) asserted that the process of sharing information and experiences with the group enables members to learn from each other. Collective intelligence (Lévy, 1994) described a shared or group intelligence that emerges from collaboration and competition.
Connectivism	Criticisms	Kerr claims that although technology affects learning environments, existing learning theories are sufficient. Kop and Hill conclude that while it does not seem that connectivism is a separate learning theory, it "continues to play an important role in the development and emergence of new pedagogies, where control is shifting from the tutor to an increasingly more autonomous learner." AlDahdouh examined the relation between connectivism and Artificial Neural Network (ANN) and the results, unexpectedly, revealed that ANN researchers use constructivism principles to teach ANN with labeled training data. However, he argued that connectivism principles are used to teach ANN only when the knowledge is unknown.

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