75 research outputs found
Acute and chronic increases in predation risk affect the territorial behaviour of juvenile Atlantic salmon in the wild
Optimality models predict that territory size will decrease as the costs of defence increase. One poorly understood cost is predation risk, especially the relative influence of short- versus long-term increases in predation risk. Under natural conditions, we quantified the territorial behaviour of juvenile Atlantic salmon, Salmo salar, exposed to either acute or chronic increases in perceived predation risk. The effects of an acute increase in predation risk were assessed by exposing 18 young-of-the-year (YOY) Atlantic salmon to a control of stream water and to an alarm cue (i.e. conspecific skin extract) while monitoring their territorial behaviour. We investigated the effects of a chronic increase in perceived predation risk by quantifying the territorial behaviour of YOY salmon in control versus risky sections of seven sites, where we manipulated the perceived predation risk over a 4-week period by releasing stream water in control sections and alarm cue in risky sections. We found that salmon exposed to the alarm cue decreased the number of switches between foraging stations, but they did not change their territory size or foraging rate. As predicted, YOY salmon in risky sections had smaller territories than in control sections. However, their foraging rates and number of switches between foraging stations did not differ between treatments. Our study suggests that juvenile Atlantic salmon are sensitive to both acute and chronic increases in perceived predation risk under natural conditions, and support the predictions of optimality models that territory size decreases with increasing predation risk
Population density and territory size in juvenile rainbow trout, Oncorhynchus mykiss: implications for population regulation.
We manipulated population density of juvenile rainbow trout ( Oncorhynchus mykiss ) across a range of realistic densities in artificial stream channels, while controlling food abundance in two different ways: in Experiment 1, the total amount of food was held constant over a threefold increase in density, whereas in Experiment 2, the per capita amount of food was held constant over an eightfold increase in density. We tested the contrasting predictions that territory size (i) is not affected by population density; (ii) decreases with population density as 1/n, where n = the local population size; or (iii) decreases with population density but towards an asymptotic minimum size. In Experiment 1, territory size decreased with increasing population density. With the broader range of densities used in Experiment 2, territory size initially decreased with density and then leveled off at a minimum territory radius of 20â30 cm. Our results suggest an asymptotic minimum size of about 0.2 m2 for a 5 cm rainbow trout, similar to what is observed for high-density conditions in the wild. This minimum territory size could potentially set an upper limit on local population density and help regulate the population size of stream salmonids. </jats:p
Characteristics of strong midwifery leaders and enablers of strong midwifery leadership:An international appreciative inquiry
Objectives: This research aimed to identify the characteristics of strong midwifery leaders and explore how strong midwifery leadership may be enabled from the perspective of midwives and nurse-midwives globally. Design: In this appreciative inquiry, we collected qualitative and demographic data using a cross-sectional online survey between February and July 2022.Setting: Responses were received from many countries (n = 76), predominantly the United Kingdom (UK), Australia, the United States of America (USA), Canada, Uganda, Saudi Arabia, Tanzania, Rwanda, India, and Kenya. Participants: An international population (n = 429) of English-speaking, and ethnically diverse midwives (n = 211) and nurse-midwives (n = 218).Measurements: Reflexive thematic analysis was used to make sense of the qualitative data collected. Identified characteristics of strong midwifery leadership were subsequently deductively mapped to established leadership styles and leadership theories. Demographic data were analysed using descriptive statistics. Findings: Participants identified strong midwifery leaders as being mediators, dedicated to the profession, evidence-based practitioners, effective decision makers, role models, advocates, visionaries, resilient, empathetic, and compassionate. These characteristics mapped to compassionate, transformational, servant, authentic, and situational leadership styles. To enable strong midwifery leadership, participants identified a need for investment in midwivesâ clear professional identity, increased societal value placed upon the midwifery profession, ongoing research, professional development in leadership, interprofessional collaborations, succession planning and increased self-efficacy. Key conclusions and implications for practice: This study contributes to understandings of trait, behavioural, situational, transformational and servant leadership theory in the context of midwifery. Investing in the development of strong midwifery leadership is essential as it has the potential to elevate the profession and improve perinatal outcomes worldwide. Findings may inform the development of both existing and new leadership models, frameworks, and validated measurement tools
Characteristics of Strong Midwifery Leaders and Enablers of Strong Midwifery Leadership: An International Appreciative Inquiry
Objectives This research aimed to identify the characteristics of strong midwifery leaders and explore how strong midwifery leadership may be enabled from the perspective of midwives and nurse-midwives globally. Design In this appreciative inquiry, we collected qualitative and demographic data using a cross-sectional online survey between February and July 2022. Setting Responses were received from many countries (n=76), predominantly the United Kingdom (UK), Australia, the United States of America (USA), Canada, Uganda, Saudi Arabia, Tanzania, Rwanda, India, and Kenya. Participants An international population (n=429) of English-speaking, and ethnically diverse midwives (n=211) and nurse-midwives (n=218). Measurements Reflexive thematic analysis was used to make sense of the qualitative data collected. Identified characteristics of strong midwifery leadership were subsequently deductively mapped to established leadership styles and leadership theories. Demographic data were analysed using descriptive statistics. Findings Participants identified strong midwifery leaders as being mediators, dedicated to the profession, evidence-based practitioners, effective decision makers, role models, advocates, visionaries, resilient, empathetic, and compassionate. These characteristics mapped to compassionate, transformational, servant, authentic, and situational leadership styles. To enable strong midwifery leadership, participants identified a need for investment in midwivesâ clear professional identity, increased societal value placed upon the midwifery profession, ongoing research, professional development in leadership, interprofessional collaborations, succession planning and increased self-efficacy. Key conclusions and implications for practice This study contributes to understandings of trait, behavioural, situational, transformational and servant leadership theory in the context of midwifery. Investing in the development of strong midwifery leadership is essential as it has the potential to elevate the profession and improve perinatal outcomes worldwide. Findings may inform the development of both existing and new leadership models, frameworks, and validated measurement tools
Formar bem as mĂŁes para criar e educar boas crianças: as revistas portuguesas de educação familiar e a difusĂŁo da maternidade cientĂfica (1945-1958)
Este artigo tem como principal objetivo contribuir para a compreensĂŁo do processo de construção da maternidade cientĂfica em Portugal. Neste sentido, foi analisado um conjunto de artigos (n=628), publicados em revistas de educação familiar, entre 1945 e 1958. A anĂĄlise realizada permitiu compreender que as revistas analisadas contribuem para a difusĂŁo da maternidade cientĂfica, ou seja, da ideia de que a aquisição de conhecimento cientĂfico sobre a criação e educação das crianças Ă© elemento indispensĂĄvel ao adequado exercĂcio da função maternal. Observou-se, ainda, a existĂȘncia de diferentes estratĂ©gias de educação para a maternidade, Ă s quais estĂĄ subjacente um elemento de classe, assim como diferentes nĂveis de adesĂŁo, por parte das mulheres, Ă concepção de maternidade cientĂfica
A large-scale genome-wide association study meta-analysis of cannabis use disorder
Summary Background Variation in liability to cannabis use disorder has a strong genetic component (estimated twin and family heritability about 50â70%) and is associated with negative outcomes, including increased risk of psychopathology. The aim of the study was to conduct a large genome-wide association study (GWAS) to identify novel genetic variants associated with cannabis use disorder. Methods To conduct this GWAS meta-analysis of cannabis use disorder and identify associations with genetic loci, we used samples from the Psychiatric Genomics Consortium Substance Use Disorders working group, iPSYCH, and deCODE (20â916 case samples, 363â116 control samples in total), contrasting cannabis use disorder cases with controls. To examine the genetic overlap between cannabis use disorder and 22 traits of interest (chosen because of previously published phenotypic correlations [eg, psychiatric disorders] or hypothesised associations [eg, chronotype] with cannabis use disorder), we used linkage disequilibrium score regression to calculate genetic correlations. Findings We identified two genome-wide significant loci: a novel chromosome 7 locus (FOXP2, lead single-nucleotide polymorphism [SNP] rs7783012; odds ratio [OR] 1·11, 95% CI 1·07â1·15, p=1·84âĂâ10â9) and the previously identified chromosome 8 locus (near CHRNA2 and EPHX2, lead SNP rs4732724; OR 0·89, 95% CI 0·86â0·93, p=6·46âĂâ10â9). Cannabis use disorder and cannabis use were genetically correlated (rg 0·50, p=1·50âĂâ10â21), but they showed significantly different genetic correlations with 12 of the 22 traits we tested, suggesting at least partially different genetic underpinnings of cannabis use and cannabis use disorder. Cannabis use disorder was positively genetically correlated with other psychopathology, including ADHD, major depression, and schizophrenia. Interpretation These findings support the theory that cannabis use disorder has shared genetic liability with other psychopathology, and there is a distinction between genetic liability to cannabis use and cannabis use disorder. Funding National Institute of Mental Health; National Institute on Alcohol Abuse and Alcoholism; National Institute on Drug Abuse; Center for Genomics and Personalized Medicine and the Centre for Integrative Sequencing; The European Commission, Horizon 2020; National Institute of Child Health and Human Development; Health Research Council of New Zealand; National Institute on Aging; Wellcome Trust Case Control Consortium; UK Research and Innovation Medical Research Council (UKRI MRC); The Brain & Behavior Research Foundation; National Institute on Deafness and Other Communication Disorders; Substance Abuse and Mental Health Services Administration (SAMHSA); National Institute of Biomedical Imaging and Bioengineering; National Health and Medical Research Council (NHMRC) Australia; Tobacco-Related Disease Research Program of the University of California; Families for Borderline Personality Disorder Research (Beth and Rob Elliott) 2018 NARSAD Young Investigator Grant; The National Child Health Research Foundation (Cure Kids); The Canterbury Medical Research Foundation; The New Zealand Lottery Grants Board; The University of Otago; The Carney Centre for Pharmacogenomics; The James Hume Bequest Fund; National Institutes of Health: Genes, Environment and Health Initiative; National Institutes of Health; National Cancer Institute; The William T Grant Foundation; Australian Research Council; The Virginia Tobacco Settlement Foundation; The VISN 1 and VISN 4 Mental Illness Research, Education, and Clinical Centers of the US Department of Veterans Affairs; The 5th Framework Programme (FP-5) GenomEUtwin Project; The Lundbeck Foundation; NIH-funded Shared Instrumentation Grant S10RR025141; Clinical Translational Sciences Award grants; National Institute of Neurological Disorders and Stroke; National Heart, Lung, and Blood Institute; National Institute of General Medical Sciences.Peer reviewe
The genetic architecture of type 2 diabetes
The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of heritability. To test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole genome sequencing in 2,657 Europeans with and without diabetes, and exome sequencing in a total of 12,940 subjects from five ancestral groups. To increase statistical power, we expanded sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support a major role for lower-frequency variants in predisposition to type 2 diabetes
Shared genetic risk between eating disorder- and substance-use-related phenotypes:Evidence from genome-wide association studies
First published: 16 February 202
A large-scale genome-wide association study meta-analysis of cannabis use disorder
Background: Variation in liability to cannabis use disorder has a strong genetic component (estimated twin and family heritability about 50-70%) and is associated with negative outcomes, including increased risk of psychopathology. The aim of the study was to conduct a large genome-wide association study (GWAS) to identify novel genetic variants associated with cannabis use disorder.
Methods: To conduct this GWAS meta-analysis of cannabis use disorder and identify associations with genetic loci, we used samples from the Psychiatric Genomics Consortium Substance Use Disorders working group, iPSYCH, and deCODE (20 916 case samples, 363 116 control samples in total), contrasting cannabis use disorder cases with controls. To examine the genetic overlap between cannabis use disorder and 22 traits of interest (chosen because of previously published phenotypic correlations [eg, psychiatric disorders] or hypothesised associations [eg, chronotype] with cannabis use disorder), we used linkage disequilibrium score regression to calculate genetic correlations.
Findings: We identified two genome-wide significant loci: a novel chromosome 7 locus (FOXP2, lead single-nucleotide polymorphism [SNP] rs7783012; odds ratio [OR] 1·11, 95% CI 1·07-1·15, p=1·84 à 10-9) and the previously identified chromosome 8 locus (near CHRNA2 and EPHX2, lead SNP rs4732724; OR 0·89, 95% CI 0·86-0·93, p=6·46 à 10-9). Cannabis use disorder and cannabis use were genetically correlated (rg 0·50, p=1·50 à 10-21), but they showed significantly different genetic correlations with 12 of the 22 traits we tested, suggesting at least partially different genetic underpinnings of cannabis use and cannabis use disorder. Cannabis use disorder was positively genetically correlated with other psychopathology, including ADHD, major depression, and schizophrenia.
Interpretation: These findings support the theory that cannabis use disorder has shared genetic liability with other psychopathology, and there is a distinction between genetic liability to cannabis use and cannabis use disorder
Transancestral GWAS of alcohol dependence reveals common genetic underpinnings with psychiatric disorders
Liability to alcohol dependence (AD) is heritable, but little is known about its complex polygenic architecture or its genetic relationship with other disorders. To discover loci associated with AD and characterize the relationship between AD and other psychiatric and behavioral outcomes, we carried out the largest genome-wide association study to date of DSM-IV-diagnosed AD. Genome-wide data on 14,904 individuals with AD and 37,944 controls from 28 case-control and family-based studies were meta-analyzed, stratified by genetic ancestry (European, n = 46,568; African, n = 6,280). Independent, genome-wide significant effects of different ADH1B variants were identified in European (rs1229984; P = 9.8 x 10(-13)) and African ancestries (rs2066702; P = 2.2 x 10(-9)). Significant genetic correlations were observed with 17 phenotypes, including schizophrenia, attention deficit-hyperactivity disorder, depression, and use of cigarettes and cannabis. The genetic underpinnings of AD only partially overlap with those for alcohol consumption, underscoring the genetic distinction between pathological and nonpathological drinking behaviors.Peer reviewe
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