In object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state and implementations of behavior. In many languages, the class name is used as the name for the class, the name for the default constructor of the class, as the type of objects generated by instantiating the class; when an object is created by a constructor of the class, the resulting object is called an instance of the class, the member variables specific to the object are called instance variables, to contrast with the class variables shared across the class. In some languages, classes are only a compile-time feature, while in other languages classes are first-class citizens, are themselves objects. In these languages, a class that creates classes is called a metaclass. In casual use, people refer to the "class" of an object, but narrowly speaking objects have type: the interface, namely the types of member variables, the signatures of member functions, properties these satisfy.

At the same time, a class has an implementation, can create objects of a given type, with a given implementation. In the terms of type theory, a class is an implementation‍—‌a concrete data structure and collection of subroutines‍—‌while a type is an interface. Different classes can produce objects of the same type. A given class may have several different constructors. Types represent nouns, such as a person, place or thing, or something nominalized, a class represents an implementation of these. For example, a Banana type might represent the properties and functionality of bananas in general, while the ABCBanana and XYZBanana classes would represent ways of producing bananas; the ABCBanana class could produce particular bananas: instances of the ABCBanana class would be objects of type Banana. Only a single implementation of a type is given, in which case the class name is identical with the type name. Classes are composed from behavioral constituents. Programming languages that include classes as a programming construct offer support, for various class-related features, the syntax required to use these features varies from one programming language to another.

A class contains data field descriptions. These are field types and names that will be associated with state variables at program run time. In most languages, the structure defined by the class determines the layout of the memory used by its instances. Other implementations are possible: for example, objects in Python use associative key-value containers; some programming languages support specification of invariants as part of the definition of the class, enforce them through the type system. Encapsulation of state is necessary for being able to enforce the invariants of the class; the behavior of class or its instances is defined using methods. Methods are subroutines with the ability to operate on classes; these operations may alter the state of an object or provide ways of accessing it. Many kinds of methods exist; some types of methods are created and called by programmer code, while other special methods—such as constructors and conversion operators—are created and called by compiler-generated code.

A language may allow the programmer to define and call these special methods. Every class implements an interface by providing behavior. Structure consists of data and state, behavior consists of code that specifies how methods are implemented. There is a distinction between the definition of an interface and the implementation of that interface; some languages, provide features that separate interface and implementation. For example, an abstract class can define an interface without providing implementation. Languages that support class inheritance allow classes to inherit interfaces from the classes that they are derived from. For example, if "class A" inherits from "class B" and if "class B" implements the interface "interface B" "class A" inherits the functionality provided by "interface B". In languages that support access specifiers, the interface of a class is considered to be the set of public members of the class, including both methods and attributes. Object-oriented programming methodology dictates that the operations of any interface of a class are to be independent of each other.

It results in a layered design where clients of an interface use the methods declared in the interface. An interface places no requirements for clients to invoke the operations of one interface in any particular order; this approach has the benefit that client code can assume that t

Peter Dirck Keyser was a United States ophthalmologist. He studied at Delaware College until 1851, when he entered the chemical laboratory of Frederick A. Genth, there made analyses of minerals, the results of which were published in the American Journal of Science, were afterward incorporated in Dana's Mineralogy. In 1856 he pursued professional studies for two years. Soon after the beginning of the Civil War he became captain in the 91st Pennsylvania Regiment, served with the Army of the Potomac until after the Battle of Fair Oaks. Failing health led to his resignation, he returned to Germany, where he studied at the University of Munich, at that of Jena, receiving there the degree of M. D. in 1864. On his return to the United States, he was appointed acting assistant surgeon in the U. S. Army, was detailed to Cuyler Hospital in Germantown, Pennsylvania. In 1865 he resigned from the service to enter on his private practice. On April 15, 1865, Keyser was one of three co-Founders of the Military Order of the Loyal Legion of the United States, or MOLLUS.

It was the first post-Civil War veterans' organization, was open to men who had served in the suppression of the Rebellion and who had held a commission in the armed forces of the United States. He was assigned MOLLUS insignia number 00003; the organization exists today, composed of the descendants of those officers. He became director of the Philadelphia Ear Infirmary. In 1868 he delivered a course of lectures to physicians upon the accommodation and refraction of the eye, in 1870 he delivered the first regular course of clinical lectures on ophthalmology, given in Philadelphia, repeating the course in 1871-72. Keyser was elected ophthalmic surgeon to the medical department of the Philadelphia German Society in 1870, one of the surgeons to the Wills Ophthalmic Hospital in 1872. Keyser was a member of medical societies and of the Pennsylvania Historical Society, he was a contributor of medical papers to the journals of his profession both in the United States and Europe, his earlier works were on chemistry.

This article incorporates text from a publication now in the public domain: Wilson, J. G.. "Keyser, Peter Dirck". Appletons' Cyclopædia of American Biography. New York: D. Appleton

Arandic is a family of Australian Aboriginal languages consisting of several languages or dialect clusters, including the Arrernte group, Lower Arrernte, Pertame language and Kaytetye. Upper Arrernte dialect cluster, with five or six main dialects, with the most dominant being Central or Eastern Arrernte, spoken in and around Alice Springs itself. Lower Arrernte known as Alenjerrntarpe and Lower Southern Arrernte, was spoken by the people around the Finke River area, but it is now extinct; the last speaker was Brownie Doolan, from whom Gavan Breen managed to write up a dictionary of 1000 words. According to AIATSIS, this was a distinct language. Pertame known as Southern Arrernte, is from the country south of Alice Springs, along the Finke River and north-west of the location of speakers of Lower Arrernte. With only 20 fluent speakers left by 2018, the Pertame Project is seeking to retain and revive the language, headed by Pertame elder Christobel Swan. Renowned artist Erlikilyika was a Pertame speaker.

Ethnologue classes Pertame as a variant name for Lower Southern, but other sources vary in their classifications and descriptions of this language. Kaytetye, spoken near Barrow Creek and Tennant Creek by the Kaytetye people,) had only 120 speakers in the 2016 census, the number has been decreasing. There are differing opinions as to which are dialects and which separate languages, among linguists and among the Arrernte people themselves. Koch only distinguished Upper Arrernte and Katetye. Glottolog defines the Arandic group as comprising five Aranda dialects, plus two distinct languages and Lower Southern Aranda, an extinct language. Ethnologue defines eight Arandic languages and classifies them differently. Harold Koch "The Arandic subgroup of Australian languages". In Claire Bowern & Harold Koch, eds. Australian Languages: Classification and the Comparative Method. John Benjamins Publishing Company. Dixon, R. M. W.. Australian Languages: Their Nature and Development. Cambridge University Press

Armando Manuel de Barros Serra Marques Guedes is a political scientist, anthropologist and a former diplomat with expertise in international relations, political science and philosophy, diplomacy and defence, geopolitics. He is a professor of political science and international politics at the Universidade Nova de Lisboa, as well as the professor responsible for geopolitics at the Instituto Universitário Militar, Instituto de Estudos Superiores Militares. Marques Guedes was born in Lisbon, the son of Clara and Armando Manuel Marques Guedes, a notable Portuguese Constitutional Law Professor, the first President of the country's Constitutional Court. Born into a well-renowned family with strong academic roots, Marques Guedes was first grandson to Armando Marques Guedes, a Professor of Economics and the last Minister of Finance of Portugal's First Republic. One of his illustrious great-grand parents was José de Almeida e Silva, a famous painter as well as a professor at the Sociedade Nacional de Belas Artes, one of the founders of the Instituto Etnológico da Beira.

On his maternal side, this intellectual pattern is there too, with a lineage of academics with a Portuguese Sephardic Jewish background, that goes back for at least six generations since the mid-19th up to late-20th century, his ascendants having been trained at the Universidade de Coimbra. Marques Guedes was educated in an English school in Estoril, at Escola Salesiana in Estoril; when he was nine years old, he was sent to begin his secondary school in a French boarding school near Toulon, in southern France's L’Institution Saint Joseph – La Navarre, before returning to Portugal to conclude his high-school and pre-university training. For a year he dabbled in a specially selected twenty student national team of mathematics as he intended to become an astrophysicist and study at the Université de Louvain, in Belgium. However, he decided to read Humanities instead, he maintained an unflinching passion for cosmological subjects, adding to it another one: Ordovician palaeontology, an area in which he engages in published peer reviewed academic work for over two decades.

Marques Guedes attended the Instituto Superior de Ciências Sociais e Políticas, University of Lisbon, where he obtained his first degree in 1975, in administration. In 1976, he obtained a B. Sc. in social anthropology from the London School of Economics and Political Science. From London he moved to France, two years in 1978, he received a Diplôme en Anthropologie Sociale from the École des Hautes Études en Sciences Sociales, the EHESS, in Paris, with a thesis on Thai, Laotian and Vietnamese hunter-gatherers entitled La Ceinture Indochinoise de Chasseurs-Cueilleurs, his dissertation was awarded a prize that allowed him to maintain himself after the four-year Calouste Gulbenkian Foundation scholarship he received to go to both London and Paris. The prize was proposed and voted on by French historian Fernand Braudel and French anthropologist Maurice Godelier and formally handed to Marques Guedes by British historian Eric Hobsbawm, it allowed him to return to his London School of Economics alma mater.

At the LSE, Marques Guedes studied under Julian Pitt-Rivers, James Woodburn and Maurice Bloch, the latter two as his academic advisers. His student colleagues at the LSE included noted South-African born David Lan, filmmaker, theatre director, now at the helm of London's Young Vic Theater and of the Word Trade Centre arts hub in New York, Charlotte Seymour-Smith, daughter of the famous poet and literary critic Martin Seymour-Smith. At the EHESS, in Paris, he carried out research with Maurice Godelier. While in Paris, he attended the Collége de France mid to late 1970s weekly seminars of Michel Foucault and Claude Lévi-Strauss. All these maîtres-penseurs, albeit they developed different theoretical and methodological takes, were to exert a strong influence on Marques Guedes's theoretical leanings and preferences, the imprints of which are still felt in his contemporary academic productions. In July 1980, while pursuing PhD research in the Philippines, he was awarded a MPhil. in Social Anthropology by the London School of Economics.

He was at the time carrying out two and a half years of participant observation field research among the Atta, hunter-gatherer groups roaming the thick primary tropical rain-forests of Kalinga-Apayao, a province in the northernmost mountainous reaches of the Philippine archipelago, in the northeastern-most ranges of Luzon's Cordillera Central. During his thirty two months there he collected detailed ethnographic data on the religious and political aspects of the social life of the hitherto unstudied Atta pygmy Negrito nomads; the title of his thesis was Rituais igualitários. Ritos dos caçadores e recolectores Filipinas. After a stint of over a decade in which he left academia for a diplomatic posting in Angola, as the first Cultural Counsellor to the Portuguese Embassy in Luanda, Marques Guedes returned to Portugal in 1990 re-entering academic life. In 1996 he was awarded by the Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa a Portuguese PhD summa cum laude in Social and Cultural Anthropology.

In this work he looked at the manifold links between religio

Den Chai is a district in the southern part of Phrae Province, northern Thailand. In the reign of King Chulalongkorn, Tai people working at the gemstone mine at Doi Pok Ka Long robbed Mueang Phrae; the king ordered Phraya Surasak Montri to redress the wrongdoing. Phraya Surasak Montri based his camp in Ban Den Thap Chai. After he resolved the issue, the name of the camp became the village name; the village was upgraded to a tambon. During World War I an army base was in Den Chai, but was merged with the Lampang army base in 1933. Today it is the cavalry Phraya Chaiyabun camp. Den Chai was created as a minor district of Sung Men District on 24 January 1963, it was upgraded to a full district in 1965. Den Chai's importance grew. Neighboring districts are: Wang Chin and Sung Men of Phrae Province. National Highways Route 11 and 101 traverse Den Chai and there are regular trains to/from Bangkok daily at Den Chai Railway Station. About six kilometres from Den Chai Station in Ban Mae Phuak is Mae Phuak Station.

As of 2018, it is classified as a "train stop", not a "train station" by the State Railway of Thailand. The station building is unusual: it consists of twin two storey structures joined by a one-storey administrative office; the building was awarded a conservation award from the Association of Siamese Architects in 2016 and is now protected. The district is divided into five sub-districts. There are two townships: Den Chai covers parts of tambons Den Chai, Mae Chua, Pong Pa Wai. There are a further five tambon administrative organizations. Amphoe.com

Valarie Zeithaml is a marketing professor and author. She is the David S. Van Pelt Family Distinguished Professor of Marketing at Kenan-Flagler Business School, University of North Carolina at Chapel Hill. Zeithml is an expert in the area of services service quality. In the 1980s Zeithaml and her co-authors developed SERVQUAL, a quality management framework for services, she was named a Thomson Reuters Highly Cited Researcher in the report on "The World's Most Influential Scientific Minds." Zeithaml, Valarie. Driving Customer Equity: How Customer Lifetime Value is Reshaping Corporate Strategy. Harvard Business School Press. UNC profile