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1.
Nonlinear Dynamics Psychol Life Sci ; 27(3): 319-350, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37429006

RESUMO

Theories and studies of corruption typically focus on individual ethics and agency problems in organizations. In this paper, we use concepts from complexity science to propose a process theory that describes how corruption risk emerges from conditions of uncertainty that are intrinsic in social systems and social interactions. We posit that our theory is valid across multiple levels of scale in social systems. We theorize that corruption involves dynamics that emerge when agents in a system take actions that exploit disequilibrium conditions of uncertainty and ethical ambiguity. Further, systemic corruption emerges when agent interactions are amplified locally in ways that create a hidden value sink which we define as a structure that extracts, or 'drains,' resources from the system for the exclusive use of certain agents. For those participating in corruption, the presence of a value sink reduces local uncertainties about access to resources. This dynamic can attract others to join the value sink, allowing it to persist and grow as a dynamical system attractor, eventually challenging broader norms. We close by identifying four distinct types of corruption risk and suggest policy interventions to manage them. Finally, we discuss ways in which our theoretical approach could motivate future research.

2.
Heredity (Edinb) ; 117(1): 51-61, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27142779

RESUMO

We develop a novel approach to identify regions of the genome underlying population genetic differentiation in any genetic data where the underlying population structure is unknown, or where the interest is assessing divergence along a gradient. By combining the statistical framework for genome-wide association studies (GWASs) with eigenvector decomposition (EigenGWAS), which is commonly used in population genetics to characterize the structure of genetic data, loci under selection can be identified without a requirement for discrete populations. We show through theory and simulation that our approach can identify regions under selection along gradients of ancestry, and in real data we confirm this by demonstrating LCT to be under selection between HapMap CEU-TSI cohorts, and we then validate this selection signal across European countries in the POPRES samples. HERC2 was also found to be differentiated between both the CEU-TSI cohort and within the POPRES sample, reflecting the likely anthropological differences in skin and hair colour between northern and southern European populations. Controlling for population stratification is of great importance in any quantitative genetic study and our approach also provides a simple, fast and accurate way of predicting principal components in independent samples. With ever increasing sample sizes across many fields, this approach is likely to be greatly utilized to gain individual-level eigenvectors avoiding the computational challenges associated with conducting singular value decomposition in large data sets. We have developed freely available software, Genetic Analysis Repository (GEAR), to facilitate the application of the methods.


Assuntos
Biologia Computacional/métodos , Genética Populacional , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Algoritmos , Evolução Molecular , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Reprodutibilidade dos Testes , Seleção Genética
3.
Mol Psychiatry ; 19(2): 253-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23358156

RESUMO

Intelligence in childhood, as measured by psychometric cognitive tests, is a strong predictor of many important life outcomes, including educational attainment, income, health and lifespan. Results from twin, family and adoption studies are consistent with general intelligence being highly heritable and genetically stable throughout the life course. No robustly associated genetic loci or variants for childhood intelligence have been reported. Here, we report the first genome-wide association study (GWAS) on childhood intelligence (age range 6-18 years) from 17,989 individuals in six discovery and three replication samples. Although no individual single-nucleotide polymorphisms (SNPs) were detected with genome-wide significance, we show that the aggregate effects of common SNPs explain 22-46% of phenotypic variation in childhood intelligence in the three largest cohorts (P=3.9 × 10(-15), 0.014 and 0.028). FNBP1L, previously reported to be the most significantly associated gene for adult intelligence, was also significantly associated with childhood intelligence (P=0.003). Polygenic prediction analyses resulted in a significant correlation between predictor and outcome in all replication cohorts. The proportion of childhood intelligence explained by the predictor reached 1.2% (P=6 × 10(-5)), 3.5% (P=10(-3)) and 0.5% (P=6 × 10(-5)) in three independent validation cohorts. Given the sample sizes, these genetic prediction results are consistent with expectations if the genetic architecture of childhood intelligence is like that of body mass index or height. Our study provides molecular support for the heritability and polygenic nature of childhood intelligence. Larger sample sizes will be required to detect individual variants with genome-wide significance.


Assuntos
Proteínas de Transporte/genética , Inteligência/genética , Herança Multifatorial , Adolescente , Criança , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Técnicas de Genotipagem , Humanos , Testes de Inteligência , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Característica Quantitativa Herdável , Software , População Branca/genética
4.
Int J Obes (Lond) ; 33(11): 1235-42, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19721450

RESUMO

OBJECTIVE: To identify common loci and potential genetic variants affecting body mass index (BMI, kg m(-2)) in study populations originating from Europe. DESIGN: We combined genome-wide linkage scans of six cohorts from Australia, Denmark, Finland, the Netherlands, Sweden and the United Kingdom with an approximately 10-cM microsatellite marker map. Variance components linkage analysis was carried out with age, sex and country of origin as covariates. SUBJECTS: The GenomEUtwin consortium consists of twin cohorts from eight countries (Australia, Denmark, the Netherlands, Finland, Italy, Norway, Sweden and the United Kingdom) with a total data collection of more than 500,000 monozygotic and dizygotic (DZ) twin pairs. Variance due to early-life events and the environment is reduced within twin pairs, which makes DZ pairs highly valuable for linkage studies of complex traits. This study totaled 4401 European-originated twin families (10,535 individuals) from six countries (Australia, Denmark, the Netherlands, Finland, Sweden and the United Kingdom). RESULTS: We found suggestive evidence for a quantitative trait locus on 3q29 and 7q36 in the combined sample of DZ twins (multipoint logarithm of odds score (MLOD) 2.6 and 2.4, respectively). Two individual cohorts showed strong evidence independently for three additional loci: 16q23 (MLOD=3.7) and 2p24 (MLOD=3.4) in the Dutch cohort and 20q13 (MLOD=3.2) in the Finnish cohort. CONCLUSION: Linkage analysis of the combined data in this large twin cohort study provided evidence for suggestive linkage to BMI. In addition, two cohorts independently provided significant evidence of linkage to three new loci. The results of our study suggest a smaller environmental variance between DZ twins than full siblings, with a corresponding increase in heritability for BMI as well as an increase in linkage signal in well-replicated regions. The results are consistent with the possibility of locus heterogeneity for some genomic regions, and indicate a lack of major common quantitative trait locus variants affecting BMI in European populations.


Assuntos
Índice de Massa Corporal , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 7/genética , Ligação Genética/genética , Locos de Características Quantitativas/genética , Gêmeos Dizigóticos/genética , Adulto , Idoso , Estudos de Coortes , Europa (Continente) , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Gêmeos/genética , População Branca/genética
5.
J Healthc Manag ; 54(3): 191-206; discussion 206-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19554799

RESUMO

Healthcare spending will exceed $4 trillion by 2017, a trend that is leading executives to implement information technology (IT) systems to contain these rising costs. Studies show that numerous factors determine the outcome and net benefits of IT in healthcare. However, what happens when a newly implemented IT system results in negative outcomes? We explore this question by examining a newly implemented IT system in a large hospital that was yielding none of the benefits for which its designers had hoped. Using an expanded set of analytic lenses, our in-depth study found that political issues were a major stumbling block to the implementation of this IT system, as the interests of IT managers were different from those of the system's users. In addition, cultural values among these stakeholders were not aligned. The new IT system carried very different meanings for these two key groups. These political and cultural issues, which reflect a broader set of factors than is commonly applied in IT or in management, led to specific recommendations designed to improve the system's viability and benefits. In a follow-up analysis we found that these alternative lenses helped increase the intended usage of the IT system by 16 percent in the first year, yielding a 20 percent improvement in performance. By better understanding the cultural and political significance of IT implementation, managers may thus improve the effectiveness of new information technologies for containing costs in hospitals.


Assuntos
Eficiência Organizacional , Sistemas de Informação Hospitalar/organização & administração , Comportamento do Consumidor , Implementação de Plano de Saúde , Hospitais de Ensino/organização & administração , New England , Cultura Organizacional , Inovação Organizacional
6.
Diabetologia ; 50(9): 1880-1888, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17624514

RESUMO

AIMS/HYPOTHESIS: The cluster of obesity, insulin resistance, dyslipidaemia and hypertension, called the metabolic syndrome, has been suggested as a risk factor for cardiovascular disease and type 2 diabetes. The aim of the present study was to evaluate whether there are common genetic and environmental factors influencing this cluster in a general population of twin pairs. MATERIALS AND METHODS: A multivariate genetic analysis was performed on nine endophenotypes associated with the metabolic syndrome from 625 adult twin pairs of the GEMINAKAR study of the Danish Twin Registry. RESULTS: All endophenotypes showed moderate to high heritability (0.31-0.69) and small common environmental variance (0.05-0.21). In general, genetic and phenotypic correlations between the endophenotypes were strong only within sets of physiologically similar endophenotypes, but weak to moderate for other pairs of endophenotypes. However, moderate correlations between insulin resistance indices and either obesity-related endophenotypes or triacylglycerol levels indicated that some common genetic backgrounds are shared between those components. CONCLUSIONS/INTERPRETATION: We demonstrated that, in a general population, the endophenotypes associated with the metabolic syndrome apparently do not share a substantial common genetic or familial environmental background.


Assuntos
Síndrome Metabólica/genética , Adulto , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Meio Ambiente , Feminino , Humanos , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Lipídeos/sangue , Lipoproteínas/sangue , Masculino , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/fisiopatologia , Fenótipo , Gêmeos Dizigóticos , Gêmeos Monozigóticos
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