bluuebunny/crossref_metadata_2025 huggingface dataset:
Iuventius Celsus Titus Aufidius Hoenius Severianus, Publius
Authors: Janssen K. P. S.
Published: April 2016

Publius Iuventius Celsus Titus Aufidius Hoenius Severianus, also known as Celsus filius or Celsus the Younger, was a prominent jurist during the early second century ce. Holder of an important number of magistracies over the course of his illustrious career, including two consulships and the position of governor of both Thrace and the province of Asia, he was particularly favoured by emperor Hadrian, who made him a member of the consilium principis. He also acted as head of the Proculian school, a position previously held by his father. His works, particularly his Digesta, proved to be highly regarded by his fellow jurists as well as influential, as is shown by their frequent inclusion in Justinian’s collection of the same name. Celsus continues to have a reputation for both abrasiveness and originality, but he is best known for his definition of law as ‘the art of the good and just’ (ius est ars boni et aequi).
Judaea-Palaestina
Authors: Isaac Benjamin
Published: April 2016

Hebrew: יהודה = Yehuda; Greek: Ἰουδαία = Ioudaia; Latin: Iudaea. Judaea was subject to the Hellenistic kingdoms and then, for a period of time, was an independent kingdom. Subjugated by Rome, it was first a dependent kingdom, then annexed as a Roman province. After two serious rebellions, it was renamed Syria-Palaestina. The Roman garrison was increased in stages till there were two legions and a comparable number of auxiliaries. The most tangible long-term effect of their presence was the organization of a system of roads all over the province. Urbanization can be traced from the Hellenistic until the Byzantine period.
acoustics
Authors: Raffa Massimo
Published: April 2016

From the earliest stages of Greek thought, sound was thought to originate as the result of an impact between two objects. At first it was believed that the swiftness and force of the impact affected both volume and pitch; then it became clear that these were two different parameters. Pitch, in particular, was connected either to quantitative factors, such as the speed of the movement or the number of subsequent impacts, or to qualitative ones, like the idiotes (“peculiarity”) theorized by Theophrastus. The least investigated parameter of sound is timbre, which was usually attributed to the physical characteristics of the source.
Nemea
Authors: Shelton Kim
Published: April 2016

Nemea is a fertile upland valley in southern Corinthia where the Sanctuary of Zeus and its panhellenic festival with athletic games was founded in the 6th century bce. After a period of disruption in the Classical period, when the games were removed and celebrated in Argos, the later 4th century bce saw a renewal of the games at the site which underwent a substantial building program with a new temple, stadium, and facilities for athletes and festival participants. A hero shrine in the form of a tumulus was constructed in the southwestern part of the sanctuary in the Iron Age and was rebuilt with a stone perimeter wall in the late 4th century. The Nemea valley was occupied and farmed from prehistory through the medieval period when the pagan sanctuary was converted for Christian worship with the construction of a basilica from the spolia of the Temple of Zeus.
painting, Greek
Authors: Plantzos Dimitris
Published: April 2016

After a long hiatus following the collapse of the palatial civilizations of the Bronze Age, wall and panel painting was reintroduced to Greece during the Early Iron Age. The first archaeological finds date from the advanced 7th century bce and include mural fragments and clay plaques used to decorate temples. Early examples (down to the early 5th century bce) are polychrome, with strong outlines and flatly painted surfaces without any sense of volume or depth of field. Their themes are often taken from myth, contemporary warfare, and religious rituals; inscriptions are customarily used to name the figures or scenes depicted.

A series of breakthroughs occurred in the 5th century bce. Composition became more sophisticated, an innovation attributed to Polygnotus of Thasos; shading and tonal contouring were introduced toward the end of the century, allegedly invented by Apollodorus of Athens. Painters often acquired high social status, as we may infer from stories about Zeuxis of Heraclea or Parrhasius of Ephesus. According to later authorities, the 4th century bce saw the greatest achievements of Greek painting and some works from this era, mostly from burial monuments, survive. A series of tombs from Macedonian sites (chiefly those at Vergina, Lefkadia, and Thessaloniki) illustrate significant advancements in the balancing of light and shade and the rendering of three-dimensional space, even with respect to elements of landscape. Many of these inventions were attributed to Apelles of Cos, who acquired fame and wealth working for Alexander of Macedon. Painting was practiced widely in the Hellenistic world, and aspects of Greek iconography and style were later introduced to Roman Italy.
Paulinus of Nola, c. 352/3–c. 431 CE
Authors: Trout Dennis E.
Published: April 2016

Meropius Pontius Paulinus was a Gallo-Roman aristocrat whose social network, wealth, and education led him to the prestigious governorship of the Italian province of Campania. After returning to Gaul in the mid-380s, however, Paulinus abandoned his secular career and life-style, withdrawing in 395 to live as a monachus at the memorial shrine of the confessor Felix, just outside the Campanian town of Nola. From there he nurtured epistolary friendships with such leading literary and ecclesiastical figures of his day as Augustine, Jerome, and Sulpicius Severus, and managed the burgeoning cult of St. Felix. Paulinus’ surviving letters and poems, many devoted to the feast day of Felix, reveal his attitudes and values, illuminate his social and spiritual relationships, preserve vivid traces of the literary and aesthetic evolution of Latin literature under the influence of Christian ideas, and document the emergence of the late antique cult of the saints. All of this makes Paulinus a remarkable representative of many of the forces reshaping Roman society and religion in the later Empire.
Plato, life and work, c. 429–347 BCE
Authors: Annas Julia
Published: April 2016

Accounts of Plato’s life are elusive. We cannot use Plato’s life to contextualize his ideas because we have no firm grasp on the life. This suits Plato’s intent in using the dialogue form, in which he never appears as a participant. Influenced by Socrates, Plato never presents philosophical positions on his own authority but presents them as resulting from arguments and as being put forward for further argument. For Plato, it is only by philosophical engagement with an idea of his that you can come to accept it—if you do—in the right way, a way that eventually gives you knowledge of it.
policing, Greek
Authors: Harris Edward M.
Published: April 2016

Greek city-states made a strict distinction between public officials and private individuals and placed the main responsibility for policing crimes in the hands of officials. At Athens the Council of 500 and Areopagus had wide powers in detecting and punishing offenders; at Sparta the ephors exercised broad powers over citizens and perioikoi (members of a dependent community). There were many officials to police the Attic countryside. Greek city-states also had many officials to enforce market regulations and laws about buildings and to keep order in sanctuaries and in gymnasia. By contrast, private individuals were allowed to use deadly force in only a few very restricted circumstances.
Proba, Faltonia Betitia
Authors: Cullhed Sigrid Schottenius
Published: April 2016

Faltonia Betitia Proba (fl. late 4th century) was a Roman poet, writer of a Christian cento (Lat. for patchwork), which circulated in the Eastern and Western Empire toward the end of the 4th century. The work consists of 694 verses culled from Virgil’s Eclogues, Georgics, and Aeneid, narrating episodes from Genesis, Exodus, and the four Gospels. The narrative sections are interspersed with proems, interludes, and epilogues pervaded by a confessional and devotional theme. The declared intention of the poet is to relate the “mysteries of Virgil” (arcana . . . vatis, v.12) and to show that Virgil “sang about the pious feats of Christ” (Vergilium cecinisse . . . pia munera Christi v. 23). This makes Proba one of the first Roman poets to have actively appropriated Virgil as a Christian prophet.

There are over a hundred manuscripts containing Proba’s cento, the oldest of which date back to the 8th century, and a large number of early modern editions. Thanks to Giovanni Boccaccio’s De mulieribus claris (1374), Proba became important in the querelle des femmes as an example of an educated woman.
shipwrecks, ancient
Authors: Carlson Deborah N.
Published: April 2016

Underwater archaeology and the excavation of ships and boats inform us about the size, construction, lading, and operation of watercraft in the ancient Mediterranean. Their findspots include shallow coastal waters and rivers, deep waters of the open sea, and silted harbours. The vast majority of ancient shipwrecks that have survived were transporting cargoes of raw materials (metal and glass ingots, stone blocks), finished goods (ceramic tableware, stone sculpture, metal tools, weapons, and containers), as well as comestible (wine, oil, nuts, meat, etc.) or organic (pitch, tar) commodities typically carried inside two-handled clay transport jars called amphoras. Thorough excavation and analysis of ancient shipwrecks contribute to larger dialogues about maritime trade and the economy, construction techniques and technology, travel, and navigation.
Solon, Athenian politician and poet, late 7th century to early 6th century BCE
Authors: Harris Edward M.
Published: April 2016

Solon was an Athenian lawgiver who wrote poetry and enacted laws in 594/3 bce. He confronted a chaotic situation in Attica caused by violence and raids for plunder and slaves. Solon created four property classes and distributed power among various sections of society. His main aims were to prevent tyranny, the concentration of power in the hands of one man, and to strengthen formal institutions. Solon abolished enslavement for debt, gave all citizens the right to have their cases heard in court, and allowed all citizens to bring accusations on behalf of those who had been wronged. Solon did not enact a cancellation of debt but abolished payment for protection by poor citizens to local leaders. Finally, he legislated not only for the élite but for all citizens on a wide range of topics ranging from family and property to funerals and religion. It is difficult, however, to determine in many cases whether the laws attributed to him are genuine or not.
Thera
Authors: Manning Sturt W.
Published: April 2016

The volcano of Thera (Santorini) is the southernmost of the Cycladic islands in the Aegean and offered an important harbour and nexus of communication for the region. A rich archaeological history attesting to widespread contacts was dramatically abbreviated in the middle of the 2nd millennium bce when there was an enormous volcanic eruption that buried most of the island. This entombment, while ending life on the island for hundreds of years, preserved buildings, artefacts, and notably a large body of wall-paintings that form the greatest collection of prehistoric art from the region. Thera was resettled in the early Iron Age and is best known in classical literature for sending a colony to Cyrene (Libya). The ancient city of Thera has remains from the Geometric through the Roman period; the island was a naval base under the Ptolemaic Empire. Thera came to scholarly attention in the later 19th century ce when a combination of quarrying pumice on the island for use in the Suez Canal (1859–1869) and a set of small eruptions (1866–1870) attracted scientific attention and highlighted the buried archaeology.
Terentius Varro, Marcus
Authors: Kaster Robert A.
Published: April 2016

Varro (according to Petrarch) was “the third great light of Rome”—after Vergil and Cicero—and certainly Rome's greatest scholar. Though the great bulk of his work survives only in fragments, the quotations and paraphrases that those fragments preserve make his influence on subsequent writers evident: much of later Latin literature, from the Aeneid of Vergil down to St. Augustine's City of God, would look very different had they been unable to draw upon his learning. His writings covered nearly every branch of inquiry: history, geography, rhetoric, law, philosophy, music, medicine, architecture, religion, and more.
architects
Authors: Senseney John R.
Published: April 2016

Modern distinctions between architecture and engineering do not readily apply to the work of architects throughout Greek and Roman history. In the design of buildings, architects’ roles and approaches changed over time. In the Classical period, Greek architects’ design specifications may have determined the forms of individual elements. According to an alternative view, the on-site nature of architects’ work may have coincided with a design process that overlapped with construction, in which masons contributed to design in a collaborative way. Beyond architects’ traditional responsibility for supplying full-scale plastic and graphic models, design by way of reduced-scale drawing was well established by the Hellenistic period. The Imperial era exploitation of Roman concrete gave architects a greater ability to project volumes through reduced-scale drawing.

Alongside career architects, amateur architects from the social elite oversaw projects in service to their communities or for their own leisure or use. In the Archaic period, architects of monumental Greek temples were responsible for the building phases and machines used in the construction process, with an increasing focus on formal design during the Classical period. Architects travelling in pursuit of commissions spread architectural ideas and influences throughout antiquity. Architects of Ionian works may have arrived in Italy as early as the Archaic period. In the Middle Republic, the presence of Greek architects in Roman environs is reflected in textual sources as well as in the use of Greek marble, building types, and spatial layouts. Similarly, the Roman architect Cossutius worked in Hellenistic contexts during this same period.
Archytas of Tarentum
Authors: Huffman Carl
Published: April 2016

Archytas led the democratic Greek city-state of Tarentum and served as a successful general. He was a leading mathematician in the first half of the fourth century bce and a prominent Pythagorean philosopher. He famously sent a ship to save Plato from the Tyrant Dionysius I of Sicily, although his relationship to Plato was complex. Only four fragments of his genuine writings survive, but many fragments of works forged in his name are found among the Pythagorean pseudepigrapha. He solved the famous mathematical puzzle known as the duplication of the cube and gave a celebrated argument for the infinity of the universe. He was the foremost Pythagorean music theorist and devised mathematical descriptions of the musical scales of his day. He championed the four mathematical sciences that became the quadrivium of the Middle Ages. Anecdotes about him convey an ethics that values reason over pleasure and praises self-control.
materialism
Authors: Porter James I.
Published: April 2016

Materialism, the belief that matter is a primary constituent of reality, is a constant feature of ancient Greek and Roman thought, and also one of its most contested and productive ideas: matter was a never-ending source of fascination and ambivalence in antiquity, while modernity inherited these same obsessions. Homer is an intuitive materialist. Later philosophers were divided over the definition and value of matter. Because a “pure” definition of matter proved so difficult to maintain in any coherent fashion, cross-overs between materialism and immaterialism, mostly unacknowledged, were the rule in antiquity. Immaterialism gradually gained the upper hand, thanks to the offices of Platonism, then of Christianity, and, from the advent of the secular age, of classicism. But not even immaterialism could rid itself of the lures of matter. Only now are the attractions and complexities of matter and materialism in ancient thought and experience being appreciated once again.
Pulcheria, Roman Augusta, 414–453 CE
Authors: Elton Hugh
Published: April 2016

Pulcheria was a Roman empress in the early to mid-5th century ce, one of the sisters of the eastern Roman emperor Theodosius II (408–450). Pulcheria spent her entire life in Constantinople (modern Istanbul) and its suburbs where she was a prominent public figure. She has been described as being influential in the First Council of Ephesus in 431 and the Council of Chalcedon in 451, and as a significant founder of churches in Constantinople. Following the death of the childless Theodosius in 450, Marcian (450–457) became emperor and then married Pulcheria. Aged 55, Pulcheria died in Constantinople in July 453. Many ancient and modern interpretations of Pulcheria’s life rely heavily on later source material, with the result that she was more influential in historiography from the 6th century onward than in her own lifetime. She is portrayed very differently by two contemporary historians, Sozomen and Socrates Scholasticus. In Sozomen’s account, she is represented as managing the Roman Empire in the early part of Theodosius’ reign. Socrates Scholasticus, however, omits her from his history. These two different perspectives probably relate to conflict between Pulcheria and Eudocia, Theodosius’ wife from 421.
film and television
Authors: Cyrino Monica S.
Published: April 2016

Ancient Greece and Rome play starring roles as ideal sites for the iconic characters and plots that cinema and television use to depict the spectacle of the ancient world. The viewing audience is invited to experience the cinematic and televisual depiction of classical antiquity as it is deployed to accomplish a number of different objectives: the image of the ancient world on screen can be used to support contemporary political goals, to interrogate current social issues, or to engage in cultural debates about the modern world’s connection to the classical past. Since the ancient Greek and Roman worlds are frequently used as the visual and narrative backdrop for adventure and romance, the audience is often thrilled to view the luxury, decadence, and excess notoriously enjoyed by the uninhibited ancients. Viewers of films and television series about the ancient world remain engaged in a long and sometimes complex relationship with the representation of classical antiquity on screen, an engagement that has been well analyzed in the last few years by scholars and critics.
Plato, knowledge and its objects
Authors: Annas Julia
Published: April 2016

Plato’s interest in knowledge takes its start from Socrates’s concern to discover experts who understand their subject matter and can explain it. Throughout the dialogues it is developed in a variety of ways. The best known include: the idea in the Meno that understanding cannot be explained by our experience and so must be “recollected” by our soul before embodiment; the idea, developed in the Phaedo and Republic, that knowledge is a structured hierarchical whole, depending on the good; and the arguments about knowledge in these dialogues which lead to debates as to whether Plato does, or does not, hold that knowledge is only of Forms while our encounters with the world of our experience can produce only belief (the so-called two-worlds view).
annona (grain)
Authors: Erdkamp Paul
Published: April 2016

Imperial Rome was by far the largest city of its time, and feeding its populace—about one million according to most estimates—required an ever-watchful eye on the part of the authorities. The system supplying Rome, the armies, and some other cities with grain and other foodstuffs came to be known as the annona. The Roman authorities began to intervene directly in the food supply of the city of Rome in the mid-Republican period. A momentous step in this development was the introduction of the grain distribution (frumentatio) by C. Sempronius Gracchus in 123 bce. In the Principate, the annona became a central feature of the relationship between the emperor and the capital’s inhabitants. At the end of Augustus’s reign the office of the annona came to be headed by a praefectus annonae, who had recourse to a staff of subordinates in Rome, Ostia, and Puteoli. Apart from the produce of the imperial estates, Rome collected tax grain primarily in Sicily, Sardinia, and Africa, and from Augustus onwards in Egypt; Rome was then largely sustained by this flow of public grain. The main responsibility of the praefectus annonae was to administer the transportation by means of shipping contracts from the grain provinces to Rome and to curb fraud and speculation on the grain market. The prefect also offered legal support for private businessmen involved in the annona. Part of the public stock was distributed at the frumentationes, which fed a significant part, but not all, of the populace. When Constantinople was founded as a new capital by Constantine, Rome lost access to the Egyptian tax-grain and relied heavily on Africa for grain and olive oil. The system of the annona was enforced more strictly, and shippers involved in the food supply of Rome found themselves bound to their obligations to the annona. In the West, the system ended when Africa was conquered by the Vandals in 429 ce. In the East, Constantinople continued to rely on Egypt until it was conquered by the Persians in 617 ce.
Athenaeus (2) Mechanicus
Authors: Whitehead David
Published: April 2016

Athenaeus (2) Mechanicus is the named author of a surviving treatise On Machines; military ones, for use in siege-warfare. The work is addressed to a ‘Marcellus,’ and nowadays orthodoxy identifies him with M. Claudius Marcellus, the short-lived (42–23 bce) nephew & son-in-law of Augustus. That in turn makes it plausible that the writer himself is Athenaeus of Seleucia-on-the-Calycadnus, a Cilician Greek intellectual known to have been in Rome in the 20s, and a contemporary, in that milieu, of Vitruvius. There is indeed material common to A.’s treatise and to sections of Book 10 of Vitruvius' On Architecture—material that, it seems, they took from their teacher Agesistratus of (?)Rhodes.

Short and not always coherent though it is, the On Machines has a two-fold importance. One is in the material mentioned already: Athenaeus and Vitruvius in tandem (together with a middle-Byzantine version of the same material) provide a succinct but useful summary history of military machinery from its beginnings to the early Hellenistic period, highlighting especially the mechanici who served Alexander the Great. But beyond that, Athenaeus offers valuable insights into late-Hellenistic culture, when an educated dilettante felt entitled to make his own contribution to such a technical genre.
Voluntary International Migration
Authors: Money Jeannette , Kazemian Sara S. , Taylor Timothy W.
Published: April 2016

Although migration has been a human phenomenon from time immemorial, international migration in the contemporary sense is usually dated from the Treaty of Westphalia (1648), which created a state system and the concept of state sovereignty with the associated power to control borders. Migration is usually divided into two categories, “forced” and “voluntary.” This is a useful dividing line, even though it is widely acknowledged that migrants have multiple reasons for moving and that there is often no clear dividing line to distinguish “forced” versus “voluntary” migrants. This article covers only voluntary international migration, both short term and long term. It does not cover the research on forced migration flows (refugees and asylum seekers) as defined in the United Nations Convention and Protocol relating to the Status of Refugees (1951 and 1967). International migration—defined as individuals living outside their country of origin for more than one year—remains the exception rather than the rule. The decline of transportation and communication costs has increased human mobility, with international travel expanding exponentially since the Second World War. Although the absolute number of migrants continues to increase, as a proportion of the population, international migration has remained relatively stable, running around 3 percent of the global population. International migrants travel in all directions, with at least half moving within the Global South. However, the distribution of international migrants is not uniform; typically migrants move from poorer, more unstable states to wealthier, more stable states. And international migration has become a salient political issue virtually everywhere: in receiving societies, in sending societies, and even in transit societies. So a bibliographical article on the various dimensions of international migration is timely. In this second edition, updated through June 2019, the citations in each section have expanded and sections have been added to reflect the breadth and depth of contemporary research. Subsequent to the overview of international migration and migration processes, the literature is organized around six themes: the economic consequences of immigration; immigration control and enforcement; specific migration flows; immigrant incorporation; migration governance, including migrant rights; and linkages between international migration and other international issues, such as security, trade, aid, and development. This article reflects scholarship on international migration produced in the Global North and/or published in globally prominent scholarly journals. Additional resources, in regional or national journals and books, are often referenced in the articles and books cited in this bibliography.
Desegregation and Integration
Authors: Ayscue Jennifer , Frankenberg Erica
Published: April 2016

In the landmark 1954 Brown v. Board of Education case, the Supreme Court unanimously decided that racial segregation was unconstitutional and “inherently unequal.” At that time, desegregation efforts focused primarily on the South and the desegregation of black and white students. The South received attention because most of the seventeen states that had de jure, or legally sanctioned, segregation were located in the South; efforts were concentrated on black and white students because they comprised the majority of public school students at that time. Today, school segregation is a national issue that reaches across all regions of the country and stratifies what is now a multiracial student population by race, class, and language. School desegregation history in the United States is characterized by several decades of progress, peaking in the 1980s, and a subsequent retreat; this pattern is evident in both the judicial support of desegregation and the trends measuring progress in desegregation. Segregated schools are consistently linked to unequal educational opportunities and outcomes, while desegregated and diverse schools are associated with numerous benefits for students of all races. The causes of school segregation (and the re-segregation of previously desegregated schools) are complicated; they include residential segregation, legal constraints, termination of court orders, student assignment policies that deprioritize diversity, structural features of school and district boundaries, and unregulated forms of school choice. Given this complexity, it is not surprising that the policies for addressing segregation are similarly complex and must be carefully tailored to the local context and demography. Since the 1950s, school districts across the nation have implemented desegregation efforts in various ways, both voluntary and mandatory, with varying levels of success. However, creating and maintaining desegregation is not sufficient for truly achieving integration, which can occur through a comprehensive and deliberate structuring of classrooms and learning environments. “Desegregation” refers to a legal or political process of ending the separation and isolation of different racial and ethnic groups. Desegregation is achieved through court order or voluntary means. “Integration” refers to a social process in which members of different racial and ethnic groups experience fair and equal treatment within a desegregated environment. Integration requires further action beyond desegregation. This bibliography incorporates social science research from education, law, policy, and sociology to explore desegregation history, policies, trends, causes, and effects. It also reviews the arguments that have been made in opposition to desegregation.
Portable Technology Use in Special Education Programs and Services in the United States
Authors: Farmer Lesley
Published: April 2016

In the United States, the Individuals with Disabilities Education Act (IDEA) lists fourteen disabilities for which a student is eligible for special education services: autism, deaf-blindness, deafness, developmental delay, emotional disturbance, hearing impairment, intellectual disability, orthopedic impairment, other health impairment, specific learning disability, speech or language impairment, traumatic brain injury, visual impairment, and multiple disabilities. Services include individualized education programs consisting of assessments, interventions, and other related services. Technologies help level the learning playing field, as they can facilitate the person’s functional academic and social capabilities across settings. Particularly as technological options have increased, there is a greater possibility of matching the technology with the learning need. Thus, the intersection of assistive technology, portable devices, disabilities, K–16 communities, and special education results in the needed topic of portable technologies for formal special education. In addition, the geographic scope is largely the United States, with some Canadian overlap. The term “portable technology” generally denotes a stand-alone device that may be carried easily in one hand, such as a cell phone, small audio or video player, signal device, or laptop computer. Sometimes the terms “mobile” or “handheld” are used instead of “portable.” In educational circles, the term “mobile learning” (or “m-learning”) refers to learning activities in which the learner actively incorporates these portable or mobile devices. Therefore, for the purposes of this bibliography, computer peripherals, wheelchairs, and other appliances (such as cochlear implants) are excluded. The bibliography emphasizes fundamental texts, systematic literature reviews, and scholarly research mainly since 2016. For very similar studies, the most rigorous one was selected for inclusion; furthermore, pilot students’ single-subject cases were avoided. It should be noted that various usage studies constitute the majority of citations. Rigorous assessment concerning the impact of portable technologies on student success is uneven, and, in particular, postsecondary assessment of special education services using portable technologies is limited. Legislative history, often best archived on websites, provides legal context. Although many valuable organizations discuss portable technologies for special education, generally only research-centric ones are included in this bibliography; other resources in the bibliography, such as Grey House Publishing’s Complete Resource Guide for People with Disabilities (cited under Overviews) do list relevant organizations.
Angkor and Environs
Authors: Rooney Dawn F.
Published: April 2016

Angkor is the name of an ancient kingdom and capital of the Khmer Empire in northwestern Cambodia that flourished from the 9th century to the mid-15th century. At its peak of power in the 11th and 12th centuries, Angkor’s control extended beyond the borders of modern Cambodia over much of mainland Southeast Asia, including parts of Thailand, Malaysia, and Myanmar. Today, Angkor refers to a historical park encompassing an area of 77 square miles with ruins of some one hundred temples. Angkor is renowned for its art and architecture that was created during the Khmer Empire to honor the religious belief (Hinduism or Buddhism) of the reigning king. A vexing concern in researching the history of the Angkor kingdom is the scarcity of primary sources. As only one firsthand account of the period exists, knowledge of the ancient civilization derives from three other main sources for study: (1) more than 1,200 epigraphic inscriptions carved in sandstone on the temples in either Sanskrit or Khmer and translated into French or English that document the accomplishment of the kings; (2) sculpture, in stone and bronze; and (3) ruins of the monuments. After France established administrative control over Cambodia, Vietnam, and Laos by the end of the 19th century, the École Française d’Extrême-Orient was founded to study the history, language, and archaeology of the three countries known as Indochina. French administrators and scholars, therefore, were the first to publish research on Angkor. Their early work combines observations, local legends, and translations of inscriptions that were, at best, imperfect in the beginning. Diaries by early European travelers to Angkor in the first half of the 20th century constitute a firsthand source for impressions of the art and architecture of Angkor. Guidebooks written by French conservators of Angkor provide detailed and systematic descriptions of the temples. The closure of Cambodia for some twenty years (c. 1970–1990) due to the Pol Pot regime and the accompanying civil unrest curtailed research advances and study of the temples. Catalogues of public collections in museums published in the last decade of the 20th century and since 2000 have added substantially to knowledge of Khmer art. Recent research on the art and architecture of Angkor benefits from new technology, generous research grants, and international technical expertise. Classic publications by French scholars working at Angkor in the first half of the 20th century are cited in this article, but the emphasis is on research advances and scholarship since the 1950s.
Role of TET enzymes in DNA methylation, development, and cancer
Authors: Rasmussen Kasper Dindler , Helin Kristian
Published: April 2016

The pattern of DNA methylation at cytosine bases in the genome is tightly linked to gene expression, and DNA methylation abnormalities are often observed in diseases. The ten eleven translocation (TET) enzymes oxidize 5-methylcytosines (5mCs) and promote locus-specific reversal of DNA methylation. TET genes, and especially TET2, are frequently mutated in various cancers, but how the TET proteins contribute to prevent the onset and maintenance of these malignancies is largely unknown. Here, we highlight recent advances in understanding the physiological function of the TET proteins and their role in regulating DNA methylation and transcription. In addition, we discuss some of the key outstanding questions in the field.
Isolating Lysosomes from Rat Liver
Authors: Pryor Paul R.
Published: April 2016

This protocol describes the generation of a fraction enriched in lysosomes from rat liver. The lysosomes are rapidly isolated using density-gradient centrifugation with gradient media that retain the osmolarity of the lysosomes such that they are functional and can be used in in vitro assays.
Purification of Lysosomes Using Supraparamagnetic Iron Oxide Nanoparticles (SPIONs)
Authors: Rofe Adam P. , Pryor Paul R.
Published: April 2016

Lysosomes can be rapidly isolated from tissue culture cells using supraparamagnetic iron oxide particles (SPIONs). In this protocol, colloidal iron dextran (FeDex) particles, a type of SPION, are taken up by cultured mouse macrophage cells via the endocytic pathway. The SPIONs accumulate in lysosomes, the end point of the endocytic pathway, permitting the lysosomes to be isolated magnetically. The purified lysosomes are suitable for in vitro fusion assays or for proteomic analysis.
Quartz: structural and thermodynamic analyses across the α ↔ β transition with origin of negative thermal expansion (NTE) in β quartz and calcite
Authors: Antao Sytle M.
Published: April 2016

The temperature variation,T, of the crystal structure of quartz, SiO2, from 298 to 1235 K was obtained with synchrotron powder X-ray diffraction data and Rietveld structure refinements. The polymorphic transformation fromP3221 (low-T, α quartz) toP6222 (high-T, β quartz) occurs at a transition temperature,Ttr= 847 K. TheTvariations of spontaneous strains and several structural parameters are fitted to an order parameter,Q, using Landau theory. The change in Si atom coordinate, Six, givesTtr−Tc= 0.49 K, which indicates an α ↔ β transition that is weakly first order and nearly tricritical in character (Q4∝T). Strains give higherTtr−Tcvalues (≃ 7 K). Other fitted parameters are the oxygen Ozcoordinate, Si—Si distance, Si—O—Si and φ angles, and intensity of the (111) reflection,I111. In α quartz, the Si—Si distance increases withTbecause of cation repulsion, so the Si—O—Si angle increases (and φ decreases) and causes the thermal expansion of the framework structure that consists of corner-sharing distorted rigid SiO4tetrahedra. The Si—Si distances contract withTand cause negative thermal expansion (NTE) in β quartz because of increasing thermal librations of the O atom in the Si—O—Si linkage that occur nearly perpendicular to the Si—Si contraction. In calcite, CaCO3, the short Ca—Ca distance expands withT, but the next-nearest Ca—Ca distance, which is of equal length to theaaxis, contracts withTand causes NTE along theaaxis. The thermal librations of the atoms in the rigid CO3group increase withTalong thecaxis.
Resolving the structure of TiBe12
Authors: Jackson Matthew L , Burr Patrick A , Grimes Robin W
Published: April 2016

There has been considerable controversy regarding the structure of TiBe12, which is variously reported as hexagonal and tetragonal. Lattice dynamics simulations based on density functional theory (DFT) show the tetragonal phase space groupI4/mmmto be more stable over all temperatures, while the hexagonal phase exhibits an imaginary phonon mode, which, if followed, would lead to the cell adopting the tetragonal structure. We then report the predicted ground state elastic constants and temperature dependence of the bulk modulus and thermal expansion for the tetragonal phase.
Source Function applied to experimental densities reveals subtle electron-delocalization effects and appraises their transferability properties in crystals
Authors: Gatti Carlo , Saleh Gabriele , Lo Presti Leonardo
Published: April 2016

The Source Function (SF), introduced in 1998 by Richard Bader and Carlo Gatti, is succinctly reviewed and a number of paradigmatic applications toin vacuoand crystal systems are illustrated to exemplify how the SF may be used to discuss chemical bonding in both conventional and highly challenging cases. The SF enables the electron density to be seen at a point determined by source contributions from the atoms or a group of atoms of a system, and it is therefore well linked to the chemist's awareness that any local property and chemical behaviour is to some degree influenced by all the remaining parts of a system. The key and captivating feature of the SF is that its evaluation requires only knowledge of the electron density (ED) of a system, thereby enabling a comparison ofab initioand X-ray diffraction derived electron density properties on a common and rigorous basis. The capability of the SF to detect electron-delocalization effects and to quantify their degree of transferability is systematically explored in this paper through the analysis and comparison of experimentally X-ray derived Source Function patterns in benzene, naphthalene and (±)-8′-benzhydrylideneamino-1,1′-binaphthyl-2-ol (BAB) molecular crystals. It is shown that the SF tool recovers the characteristic SF percentage patterns caused by π-electron conjugation in the first two paradigmatic aromatic molecules in almost perfect quantitative agreement with those obtained fromab initioperiodic calculations. Moreover, the effect of chemical substitution on the degree of transferability of such patterns to the benzene- and naphthalene-like moieties of BAB is neatly shown and quantified by the observed systematic deviations, relative to benzene and naphthalene, of only those SF contributions from the substituted C atoms. Finally, the capability of the SF to reveal electron-delocalization effects is challenged by using a promolecule density, rather than the proper quantum mechanical density, to determine the changes in SF patterns along the cyclohexene, 1,3-cyclohexadiene and benzene molecule series. It is shown that, differently from the proper quantum density, the promolecular density is unable to reproduce the SF trends anticipated by the increase of electron delocalization along the series, therefore ruling out the geometrical effect as being the only cause for the observed SF patterns changes.
The Cambridge Structural Database
Authors: Groom Colin R. , Bruno Ian J. , Lightfoot Matthew P. , Ward Suzanna C.
Published: April 2016

The Cambridge Structural Database (CSD) contains a complete record of all published organic and metal–organic small-molecule crystal structures. The database has been in operation for over 50 years and continues to be the primary means of sharing structural chemistry data and knowledge across disciplines. As well as structures that are made public to support scientific articles, it includes many structures published directly as CSD Communications. All structures are processed both computationally and by expert structural chemistry editors prior to entering the database. A key component of this processing is the reliable association of the chemical identity of the structure studied with the experimental data. This important step helps ensure that data is widely discoverable and readily reusable. Content is further enriched through selective inclusion of additional experimental data. Entries are available to anyone through free CSD community web services. Linking services developed and maintained by the CCDC, combined with the use of standard identifiers, facilitate discovery from other resources. Data can also be accessed through CCDC and third party software applications and through an application programming interface.
The development and use of a crystallographic database
Authors: Görbitz Carl Henrik
Published: April 2016

To scientists working with small-molecule or organometallic compounds, the Cambridge Structural Database constitutes an extremely important tool for reference to individual crystal structures and as a data source for statistical investigations. The article by Groomet al.[(2016),Acta Cryst.B72, 171–179] provides updated information on the use, development and future of this database.
System model for analysing construction labour productivity
Authors: Tsehayae Abraham Assefa , Fayek Aminah Robinson
Published: April 2016

Purpose

Despite long-term, sustained research and industry practice, predicting construction labour productivity (CLP) using existing factor and activity modelling approaches remains a challenge. The purpose of this paper is to first demonstrate the limited usefulness of activity models and then to propose a system model approach that integrates factor and activity models for better prediction of CLP.

Design/methodology/approach

The system model parameters – comprising factors and practices – and work sampling proportions (WSPs) were identified from literature. Field data were collected from 11 projects over a span of 29 months. Activity models based on the relationship between CLP and WSPs were created, and their validity was tested using regression analysis for eight activities in the concreting, electrical and shutdown categories. The proposed system model was developed for concreting activity using the key influencing parameters in conjunction with WSPs.

Findings

The results of the regression analysis indicate that WSPs, like direct work, are not significantly correlated to CLP and fail to explain its variance. Evaluation of the system model approach for the concreting activity showed improved CLP prediction as compared to existing approaches.

Research limitations/implications

The system model was tested for concreting activity using data collected from six projects; however, further investigation into the model’s accuracy and efficacy using data collected from other labour-intensive activities is suggested.

Originality/value

This research establishes the role of WSPs in CLP modelling, and develops a system modelling approach to assist researchers and practitioners in the analysis of productivity-influencing parameters together with WSPs.
Reflecting on 10 years of focus on innovation, organisational learning and knowledge management literature in a construction project management context
Authors: Walker Derek H.T.
Published: April 2016

Purpose

This paper provides a brief critical analysis of how the focus on innovation diffusion, organisational learning and knowledge management has developed with an emphasis on the 2005-2015 period. The purpose of this paper is to provide a recent historic perspective on these concepts and suggest an integrated future focus for this research.

Design/methodology/approach

The paper identifies trends in how knowledge and learning is associated with innovation and experience based on a literature review.

Findings

The study of organisational learning and the management of knowledge and innovation diffusion is well-established in the construction and project management domains with two strongly emerging intertwined foci. On one hand, there has been a significant growing focus on learning through collaboration and the value of being a reflective practitioner. On the other hand, the exponential growth in the power of computing has led to “Big Data” reappearing to redefine data and information into pseudo-knowledge that is “blurring” the boundary of data, information and knowledge. Increasingly, we are likely to see effective innovation through more practical blending of these foci.

Originality/value

This provides a reflection on changing perspectives, on human and machine learning and knowledge management that may have a profound impact on future research themes.