University of Kent

First-principles simulation, meaning density-functional theory calculations with plane waves and pseudopotentials, has become a prized technique in condensed-matter theory. Here I look at the basics of the suject, give a brief review of the theory, examining the strengths and weaknesses of its implementation, and illustrating some of the ways simulators approach problems through a small case study. I also discuss why and how modern software design methods have been used in writing a completely new modular version of the CASTEP code. 1. Overview The simulator builds a model of a real system and explores its behaviour. The model is a mathematical one and the exploration is done on a computer, and in many ways simulation studies share the same mentality as experimental ones. However, in a simulation there is absolute control and access to detail, the ability to compute almost any observable, and given enough computer muscle, exact answers for the model. These strengths have been exploited for

BACKGROUND: CONSORT guidelines call for precise reporting of behavior change interventions: we need rigorous methods of characterizing active content of interventions with precision and specificity. OBJECTIVES: The objective of this study is to develop an extensive, consensually agreed hierarchically structured taxonomy of techniques [behavior change techniques (BCTs)] used in behavior change interventions. METHODS: In a Delphi-type exercise, 14 experts rated labels and definitions of 124 BCTs from six published classification systems. Another 18 experts grouped BCTs according to similarity of active ingredients in an open-sort task. Inter-rater agreement amongst six researchers coding 85 intervention descriptions by BCTs was assessed. RESULTS: This resulted in 93 BCTs clustered into 16 groups. Of the 26 BCTs occurring at least five times, 23 had adjusted kappas of 0.60 or above. CONCLUSIONS: "BCT taxonomy v1," an extensive taxonomy of 93 consensually agreed, distinct BCTs, offers a step change as a method for specifying interventions, but we anticipate further development and evaluation based on international, interdisciplinary consensus.

BACKGROUND: An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. METHODS: Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. RESULTS: There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): 'Knowledge', 'Skills', 'Social/Professional Role and Identity', 'Beliefs about Capabilities', 'Optimism', 'Beliefs about Consequences', 'Reinforcement', 'Intentions', 'Goals', 'Memory, Attention and Decision Processes', 'Environmental Context and Resources', 'Social Influences', 'Emotions', and 'Behavioural Regulation'. CONCLUSIONS: The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development.

Restricted maximum likelihood (REML) is now well established as a method for estimating the parameters of the general Gaussian linear model with a structured covariance matrix, in particular for mixed linear models. Conventionally, estimates of precision and inference for fixed effects are based on their asymptotic distribution, which is known to be inadequate for some small-sample problems. In this paper, we present a scaled Wald statistic, together with an F approximation to its sampling distribution, that is shown to perform well in a range of small sample settings. The statistic uses an adjusted estimator of the covariance matrix that has reduced small sample bias. This approach has the advantage that it reproduces both the statistics and F distributions in those settings where the latter is exact, namely for Hotelling T2 type statistics and for analysis of variance F-ratios. The performance of the modified statistics is assessed through simulation studies of four different REML analyses and the methods are illustrated using three examples.

We propose a new method for approximate Bayesian statistical inference on the basis of summary statistics. The method is suited to complex problems that arise in population genetics, extending ideas developed in this setting by earlier authors. Properties of the posterior distribution of a parameter, such as its mean or density curve, are approximated without explicit likelihood calculations. This is achieved by fitting a local-linear regression of simulated parameter values on simulated summary statistics, and then substituting the observed summary statistics into the regression equation. The method combines many of the advantages of Bayesian statistical inference with the computational efficiency of methods based on summary statistics. A key advantage of the method is that the nuisance parameters are automatically integrated out in the simulation step, so that the large numbers of nuisance parameters that arise in population genetics problems can be handled without difficulty. Simulation results indicate computational and statistical efficiency that compares favorably with those of alternative methods previously proposed in the literature. We also compare the relative efficiency of inferences obtained using methods based on summary statistics with those obtained directly from the data using MCMC.

The Fifth Edition of the 'Guide to Receptors and Channels' is a compilation of the major pharmacological targets divided into seven sections: G protein-coupled receptors, ligand-gated ion channels, ion channels, catalytic receptors, nuclear receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside suggestions for further reading. Available alongside this publication is a portal at http://www.GuideToPharmacology.org which is produced in close association with NC-IUPHAR and allows free online access to the information presented in the Fifth Edition.

BACKGROUND: Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. METHODS: ). For school-aged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). FINDINGS: From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. INTERPRETATION: The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity. FUNDING: UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union.

This article presents a critical review of Social Identity Theory[ Its major contributions to the study of inter`roup relations are discussed\ focusin`on its powerful explanations of such phenomena as in`roup bias\ responses of subordinate `roups to their unequal status position\ and intra`roup homo`eneity and stereotypin`[ In addition\ its stimulative role for theoretical elaborations of the Contact Hypothesis as a strate`y for improvin`inter`roup attitudes is noted[ Then _ve issues which have proved problematic for Social Identity Theory are ident! i_ed] the relationship between `roup identi_cation and in`roup bias^the self!esteem hypoth! esis^positivene`ative asymmetry in inter`roup discrimination^the effects of inter`roup similarity^and the choice of identity strate`ies by low!status `roups[ In a third section a future research a`enda for the theory is sketched out\ with _ve lines of enquiry noted as beinp articularly promisin`] expandin`the concept of social identity^predictin`comparison choice in inter`roup settin`s^incorporatin`affect into the theory^mana`in`social identities in multicultural settin`s^and inte`ratin`implicit and explicit processes[ The article concludes with some remarks on the potential applications of social identity principles[ Copyri`ht 1999 John Wiley + Sons\ Ltd[ New centuries*and new millennia even more so*often prompt re~ections on how far we have come and how far "and where# we have yet to go[ I want to use the opportunity provided by this Agenda 1999 series to engage in such a reappraisal of one of social psychology|s pre!eminent theoretical perspectives\ Social Identity Theory "SIT#[ I use the word {pre!eminent| advisedly because there can be no question that social identity concepts are widely di}used and extensively employed as explanatory tools throughout our discipline[ This can be seen from the frequency of references to SIT and related topics in our major journals which seem to have increased linearly over the past twenty years "Abrams + Hogg\ 0887^Brown + Capozza\ 1999#\ from the popularity of {social identity| as key words in conference proceedings on both sides of the Atlantic "e[g[ meetings of the European Association of Experimental

Almost 30 years ago, Hamachek (1978) suggested that 2 forms of perfectionism be distinguished, a positive form labeled "normal perfectionism" and a negative form labeled "neurotic perfectionism." Focusing on the positive, we present an overview of the different empirical conceptions of the 2 forms of perfectionism and a common framework for the 2 basic approaches: the dimensional approach differentiating 2 dimensions of perfectionism (perfectionistic strivings and perfectionistic concerns) and the group-based approach differentiating 2 groups of perfectionists (healthy perfectionists and unhealthy perfectionists). Moreover, we review the evidence demonstrating that (a) perfectionistic strivings are associated with positive characteristics and (b) healthy perfectionists show higher levels of positive characteristics compared to unhealthy perfectionists and nonperfectionists. Although questions on core facets, positive effects, and developmental antecedents of positive forms of perfectionism remain, our findings suggest that self-oriented perfectionistic strivings are positive, if perfectionists are not overly concerned about mistakes and negative evaluations by others.

In-fibre Bragg grating (FBG) sensors are one of the most exciting developments in the field of optical fibre sensors in recent years. Compared with conventional fibre-optic sensors, FBG sensors have a number of distinguishing advantages. Significant progress has been made in applications to strain and temperature measurements. FBG sensors prove to be one of the most promising candidates for fibre-optic smart structures. This article presents a comprehensive and systematic overview of FBG sensor technology regarding many aspects including sensing principles, properties, fabrication, interrogation and multiplexing of FBG sensors. It is anticipated that FBG sensor systems will be commercialized and widely applied in practice in the near future due to the maturity of economical production of FBGs and the availability of cost effective interrogation and multiplexing techniques.

The literature on fear of crime has grown rapidly in the last three decades. This paper examines the reasons for this growth and attempts to put some structure on the work to date. The inadequacies of measures of fear of crime are discussed and alternative approaches suggested. Alternative explanatory theories are compared and strategies for reducing fear reviewed.

Assessing Biodiversity Declines Understanding human impact on biodiversity depends on sound quantitative projection. Pereira et al. (p. 1496 , published online 26 October) review quantitative scenarios that have been developed for four main areas of concern: species extinctions, species abundances and community structure, habitat loss and degradation, and shifts in the distribution of species and biomes. Declines in biodiversity are projected for the whole of the 21st century in all scenarios, but with a wide range of variation. Hoffmann et al. (p. 1503 , published online 26 October) draw on the results of five decades' worth of data collection, managed by the International Union for Conservation of Nature Species Survival Commission. A comprehensive synthesis of the conservation status of the world's vertebrates, based on an analysis of 25,780 species (approximately half of total vertebrate diversity), is presented: Approximately 20% of all vertebrate species are at risk of extinction in the wild, and 11% of threatened birds and 17% of threatened mammals have moved closer to extinction over time. Despite these trends, overall declines would have been significantly worse in the absence of conservation actions.

Scholarly efforts to understand conspiracy theories have grown significantly in recent years, and there is now a broad and interdisciplinary literature. In reviewing this body of work, we ask three specific questions. First, what factors are associated with conspiracy beliefs? Our review of the literature shows that conspiracy beliefs result from a range of psychological, political, and social factors. Next, how are conspiracy theories communicated? Here, we explain how conspiracy theories are shared among individuals and spread through traditional and social media platforms. Next, what are the societal risks and rewards associated with conspiracy theories? By focusing on politics and science, we argue that conspiracy theories do more harm than good. We conclude by suggesting several promising avenues for future research.

The importance of tacit knowledge in organizational learning and innovation has become the focus of considerable attention in the recent literature. Our understanding of the nature of the links between tacit knowledge and organizational learning, however, has been hampered by the lack of a conceptual framework integrating micro-level learning activities with organizational forms and macro-level societal institutions. This paper seeks to achieve such an integrative task. It argues that there is an interactive relationship between dominant knowledge types and organizational forms. Further, the extent to which tacit knowledge constitutes the knowledge base of the firm, and how it is formed and used are powerfully shaped by the broader institutional context. The paper develops a four-fold typology at the cognitive, organizational and societal levels, as an analytical framework to explain the links between knowledge types, organizational forms and societal institutions. It shows how the three levels interact to shape the learning and innovative capabilities of firms. The theory developed in this paper represents the first attempt to integrate the diverse strands of literature and different levels of analysis into a single coherent framework.

This paper estimates the impact of foreign direct investment (FDI) on capital accumulation, and output and total factor productivity (TFP) growth in the recipient economy. Time series and panel data evidence are provided for a sample of OECD and non-OECD countries in the period 1970-90. Although FDI is expected to boost long-run growth in the recipient economy via technological upgrading and knowledge spillovers, it is shown that the extent to which FDI is growth-enhancing depends on the degree of complementarity and substitution between FDI and domestic investment.

For 10,000 years pigs and humans have shared a close and complex relationship. From domestication to modern breeding practices, humans have shaped the genomes of domestic pigs. Here we present the assembly and analysis of the genome sequence of a female domestic Duroc pig (Sus scrofa) and a comparison with the genomes of wild and domestic pigs from Europe and Asia. Wild pigs emerged in South East Asia and subsequently spread across Eurasia. Our results reveal a deep phylogenetic split between European and Asian wild boars ∼1 million years ago, and a selective sweep analysis indicates selection on genes involved in RNA processing and regulation. Genes associated with immune response and olfaction exhibit fast evolution. Pigs have the largest repertoire of functional olfactory receptor genes, reflecting the importance of smell in this scavenging animal. The pig genome sequence provides an important resource for further improvements of this important livestock species, and our identification of many putative disease-causing variants extends the potential of the pig as a biomedical model. This study presents the assembly and analysis of the genome sequence of a female domestic Duroc pig and a comparison with the genomes of wild and domestic pigs from Europe and Asia; the results shed light on the evolutionary relationship between European and Asian wild boars. The domestic pig (Sus scrofa) is an important livestock species, its genome shaped by thousands of years of domestication and, latterly, sophisticated breeding practices. A high-quality draft genome sequence for a female domestic Duroc pig is published in this issue of Nature, under the auspices of the Swine Genome Sequencing Consortium. Comparisons of the genomes of wild and domestic pigs shed light on the evolutionary relationship between European and Asian wild boars, and reveal the rapid evolution of genes involved in the immune response and in olfaction. The authors identify many possible disease-causing gene variants, increasing the potential of the pig as a biomedical model, and present a detailed analysis of endogenous porcine retroviruses, knowledge of which is important for the possible use of pigs in xenotransplantation.

This article surveys the latest developments in the literature on the impact of inward foreign direct investment (FDI) on growth in developing countries. In general, FDI is thought of as a composite bundle of capital stocks, know‐how, and technology, and hence its impact on growth is expected to be manifold and vary a great deal between technologically advanced and developing countries. The ultimate impact of FDI on output growth in the recipient economy depends on the scope for efficiency spillovers to domestic firms, by which FDI leads to increasing returns in domestic production, and increases in the value‐added content of FDI‐related production.

Introduction Recent decades have seen a major international effort to inventory tree communities in the Amazon Basin and Guiana Shield (Amazonia), but the vast extent and record diversity of these forests have hampered an understanding of basinwide patterns. To overcome this obstacle, we compiled and standardized species-level data on more than half a million trees in 1170 plots sampling all major lowland forest types to explore patterns of commonness, rarity, and richness. Methods The ~6-million-km 2 Amazonian lowlands were divided into 1° cells, and mean tree density was estimated for each cell by using a loess regression model that included no environmental data but had its basis exclusively in the geographic location of tree plots. A similar model, allied with a bootstrapping exercise to quantify sampling error, was used to generate estimated Amazon-wide abundances of the 4962 valid species in the data set. We estimated the total number of tree species in the Amazon by fitting the mean rank-abundance data to Fisher’s log-series distribution. Results Our analyses suggest that lowland Amazonia harbors 3.9 × 10 11 trees and ~16,000 tree species. We found 227 “hyperdominant” species (1.4% of the total) to be so common that together they account for half of all trees in Amazonia, whereas the rarest 11,000 species account for just 0.12% of trees. Most hyperdominants are habitat specialists that have large geographic ranges but are only dominant in one or two regions of the basin, and a median of 41% of trees in individual plots belong to hyperdominants. A disproportionate number of hyperdominants are palms, Myristicaceae, and Lecythidaceae. Discussion The finding that Amazonia is dominated by just 227 tree species implies that most biogeochemical cycling in the world’s largest tropical forest is performed by a tiny sliver of its diversity. The causes underlying hyperdominance in these species remain unknown. Both competitive superiority and widespread pre-1492 cultivation by humans are compelling hypotheses that deserve testing. Although the data suggest that spatial models can effectively forecast tree community composition and structure of unstudied sites in Amazonia, incorporating environmental data may yield substantial improvements. An appreciation of how thoroughly common species dominate the basin has the potential to simplify research in Amazonian biogeochemistry, ecology, and vegetation mapping. Such advances are urgently needed in light of the &gt;10,000 rare, poorly known, and potentially threatened tree species in the Amazon.

This article deals with the question of how migration has developed into a security issue in western Europe and how the European integration process is implicated in it. Since the 1980s, the political construction of migration increasingly referred to the destabilizing effects of migration on domestic integration and to the dangers for public order it implied. The spillover of the internal market into a European internal security question mirrors these domestic developments at the European level. The Third Pillar on Justice and Home Affairs, the Schengen Agreements, and the Dublin Convention most visibly indicate that the European integration process is implicated in the development of a restrictive migration policy and the social construction of migration into a security question. However, the political process of connecting migration to criminal and terrorist abuses of the internal market does not take place in isolation. It is related to a wider politicization in which immigrants and asylum‐seekers are portrayed as a challenge to the protection of national identity and welfare provisions. Moreover, supporting the political construction of migration as a security issue impinges on and is embedded in the politics of belonging in western Europe. It is an integral part of the wider technocratic and political process in which professional agencies – such as the police and customs – and political agents – such as social movements and political parties – debate and decide the criteria for legitimate membership of west European societies.

The International Union for Conservation of Nature (IUCN) Red List of Threatened Species was increasingly used during the 1980s to assess the conservation status of species for policy and planning purposes. This use stimulated the development of a new set of quantitative criteria for listing species in the categories of threat: critically endangered, endangered, and vulnerable. These criteria, which were intended to be applicable to all species except microorganisms, were part of a broader system for classifying threatened species and were fully implemented by IUCN in 2000. The system and the criteria have been widely used by conservation practitioners and scientists and now underpin one indicator being used to assess the Convention on Biological Diversity 2010 biodiversity target. We describe the process and the technical background to the IUCN Red List system. The criteria refer to fundamental biological processes underlying population decline and extinction. But given major differences between species, the threatening processes affecting them, and the paucity of knowledge relating to most species, the IUCN system had to be both broad and flexible to be applicable to the majority of described species. The system was designed to measure the symptoms of extinction risk, and uses 5 independent criteria relating to aspects of population loss and decline of range size. A species is assigned to a threat category if it meets the quantitative threshold for at least one criterion. The criteria and the accompanying rules and guidelines used by IUCN are intended to increase the consistency, transparency, and validity of its categorization system, but it necessitates some compromises that affect the applicability of the system and the species lists that result. In particular, choices were made over the assessment of uncertainty, poorly known species, depleted species, population decline, restricted ranges, and rarity; all of these affect the way red lists should be viewed and used. Processes related to priority setting and the development of national red lists need to take account of some assumptions in the formulation of the criteria.