649 research outputs found
On the Estimation of the Short-Circuit Impedance of Power Transformers Using Fractional Order Calculus
This paper reports investigation on the estimation of the short circuit
impedance of power transformers, using fractional order calculus to analytically
study the influence of the diffusion phenomena in the windings. The aim is to better
characterize the medium frequency range behavior of leakage inductances of power
transformer models, which include terms to represent the magnetic field diffusion
process in the windings. Comparisons between calculated and measured values are
shown and discussed
Short-Circuit Impedance of Power Transformers: the Fractional Order Calculus Approach
First IFAC Workshop on Fractional Differentiation and Its Application - 19-21 July 2004, Enseirb, Bordeaux, France - FDA'04This paper reports investigation on the modeling of the short circuit
impedance of power transformers, using fractional order calculus, analyzing the
influence of the diffusion phenomena in the windings. This aims to better
characterize the medium frequency range behavior of leakage inductances of power
transformer models, which include terms to represent the magnetic field diffusion in
the windings. Calculated and measured values are shown and compared
Los médicos y la gestión del cuidado en servicios hospitalarios de urgencia: ¿un poder profesional amenazado?
O Kanban é um arranjo tecnológico de organização do cuidado hospitalar orientado para a gestão de leitos e da clínica, que visa à qualidade e integralidade da assistência, maior rotatividade dos leitos, com consequente redução do tempo de internação e custos hospitalares. O constante e atualizado acompanhamento do paciente, compartilhado pela equipe profissional em reuniões sistemáticas é seu elemento mais marcante e inovador. O objetivo foi caracterizar os prováveis impactos da adoção de tal arranjo no poder profissional (autonomia e autoridade) dos médicos. Estudo qualitativo em hospital de urgência-emergência municipal com uso das seguintes técnicas de produção de dados: etnografia do cotidiano do hospital, com observação e registro em diários de campo, e realização de seminários compartilhados entre pesquisadores e equipes. Os médicos valorizam o trabalho multiprofissional como um qualificador de sua prática, em uma linha auxiliar e complementar. Acresce que o Kanban tende a ser controlado por “híbridos” (médicos que acumulam funções gerenciais e clínicas) que traduzem sinergias entre “gestão clínica” e “gestão de leitos”. Assim, interferências no trabalho dos médicos não são exercidas de fora, e as suas decisões clínicas continuam a condicionar o trabalho dos demais grupos profissionais. Os médicos não percebem sua autoridade e autonomia ameaçadas pelo Kanban, dada a articulação entre a autoridade administrativa e a autoridade profissional. Contudo, aspectos relacionados à hibridização e estratificação interna da profissão médica precisam ser mais convocados para o debate do poder profissional em saúde.info:eu-repo/semantics/publishedVersio
Characterization of Mesocriconema species associated to Grapevine Decline Disease in Southern Brazil.
The grapevine decline disease (GDD) is a complex disease that causes substantial losses in grape production. Ring nematode (Mesocriconema xenoplax) is frequently detected in symptomatic vineyards. Unfortunately, this nematode is frequently mis-identifed due to its similarities with other species of this genus. In this study, the hypothesis was tested that there is a species complex of Mesocriconema associated with GDD in southern Brazil. This hypothesis was based on a previous result that identifed diferent Mesocriconema species in vineyards in southern Brazil including M. xenoplax, M. curvatum, M. rusticum, M. sphaerocephalum, M. ornatum, and another seven undefned species, using only morphometric data. This current study provides the frst characterization of Mesocriconema species associated with GDD, their distribution, and variability, through the use of morphological and molecular analysis in an integrative approach.Online First
What influences national and foreign physicians’ geographic distribution? An analysis of medical doctors’ residence location in Portugal
Background
The debate over physicians’ geographical distribution has attracted the attention of the
economic and public health literature over the last forty years. Nonetheless, it is still to date
unclear what influences physicians’ location, and whether foreign physicians contribute to fill
the geographical gaps left by national doctors in any given country. The present research sets
out to investigate the current distribution of national and international physicians in Portugal, with the objective to understand its determinants and provide an evidence base for policymakers to identify policies to influence it.
Methods
A cross-sectional study of physicians currently registered in Portugal was conducted to describe the population and explore the association of physician residence patterns with relevant personal and municipality characteristics. Data from the Portuguese Medical Council
on physicians’ residence and characteristics were analysed, as well as data from the National Institute of Statistics on municipalities’ population, living standards and health care network.
Descriptive statistics, chi-square tests, negative binomial and logistic regression modelling were applied to determine: (a) municipality characteristics predicting Portuguese and International physicians’ geographical distribution, and; (b) doctors’ characteristics that could
increase the odds of residing outside the country’s metropolitan areas.
Results
There were 39,473 physicians in Portugal in 2008, 51.1% of whom male, and 40.2% between
41 and 55 years of age. They were predominantly Portuguese (90.5%), with Spanish,
Brazilian and African nationalities also represented. Population, Population’s Purchasing
Power, Nurses per capita and Municipality Development Index (MDI) were the municipality
characteristics displaying the strongest association with national physicians’ location. For
foreign physicians, the MDI was not statistically significant, while municipalities’ foreign
population applying for residence appeared to be an additional positive factor in their location
decisions. In general, being foreigner and male resulted to be the physician characteristics
increasing the odds of residing outside the metropolitan areas. However, among the
internationals, older doctors were more likely to reside outside metropolitan areas. Being
Spanish or Brazilian (but not of African origin) was found to increase the odds of being based
outside the Lisbon and Oporto metropolitan areas.
Conclusions
The present study showed the relevance of studying one country’s physician population to
understand the factors driving national and international doctors’ location decisions. A more
nuanced understanding of national and foreign doctors’ location appears to be needed to
design more effective policies to reduce the imbalance of medical services across
geographical areas.The study was supported by a research grant from the Portuguese High Commission for Health to the International Health Department of the Institute of Hygiene and Tropical.
Medicine
Decline in Diarrhea Mortality and Admissions after Routine Childhood Rotavirus Immunization in Brazil: A Time-Series Analysis
A time series analysis by Manish Patel and colleagues shows that the introduction of rotavirus vaccination in Brazil is associated with reduced diarrhea-related deaths and hospital admissions in children under 5 years of age
Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics
A detailed study is presented of the expected performance of the ATLAS
detector. The reconstruction of tracks, leptons, photons, missing energy and
jets is investigated, together with the performance of b-tagging and the
trigger. The physics potential for a variety of interesting physics processes,
within the Standard Model and beyond, is examined. The study comprises a series
of notes based on simulations of the detector and physics processes, with
particular emphasis given to the data expected from the first years of
operation of the LHC at CERN
Decreased renal function in overweight and obese prepubertal children
BACKGROUND: Obesity is a potentially modifiable risk factor for the development and progression of kidney disease, both in adults and children. We aim to study the association of obesity and renal function in children, by comparing estimated glomerular filtration rate (eGFR) in nonoverweight and overweight/obese children. Secondarily, we aim to evaluate the accuracy of equations on eGFR estimation when compared to 24-h urinary creatinine clearance (CrCl).
METHODS: Cross-sectional study of 313 children aged 8-9 y, followed in the birth cohort Generation XXI (Portugal). Creatinine and cystatin C, GFR estimated by several formulas and CrCl were compared in 163 nonoverweight and 150 overweight/obese, according to World Health Organization growth reference.
RESULTS: Overweight/obese children had significantly lower eGFR, estimated by all methods, except for CrCl and revised Schwartz formula. Despite all children having renal function in the normal range, eGFR decreased significantly with BMI z-score (differences ranging from -4.3 to -1.1 ml/min/1.73 m(2) per standard deviation of BMI). The Zappitelli combined formula presented the closest performance to CrCl, with higher correlation coefficients and higher accuracy values.
CONCLUSION: Young prepubertal children with overweight/obesity already present significantly lower GFR estimations that likely represent some degree of renal impairment associated with the complex deleterious effects of adiposity
A de novo paradigm for male infertility
Funding Information: (DFG, CRU326) to C.F. and F.T. This project was also supported in part by funding from the Australian National Health and Medical Research Council (APP1120356) to M.K.O.B., by grants from the National Institutes of Health of the United States of America (R01HD078641 to D.F.C. and K.I.A., P50HD096723 to D.F.C.) and from the Biotechnology and Biological Sciences Research Council (BB/S008039/1) to D.J.E. Funding Information: We are grateful for the participation of all patients and their parents in this study. We thank Laurens van de Wiel (Radboudumc), Sebastian Judd-Mole (Monash University), Arron Scott and Bryan Hepworth (Newcastle University) for technical support, and Margot J Wyrwoll (University of Münster) for help with handling MERGE samples and data. This project was funded by The Netherlands Organization for Scientific Research (918-15-667) to J.A.V. as well as an Investigator Award in Science from the Wellcome Trust (209451) to J.A.V. a grant from the Catherine van Tussenbroek Foundation to M.S.O. a grant from MERCK to R.S. a UUKi Rutherford Fund Fellowship awarded to B.J.H. and the German Research Foundation Clinical Research Unit “Male Germ Cells” Publisher Copyright: © 2022, The Author(s).De novo mutations are known to play a prominent role in sporadic disorders with reduced fitness. We hypothesize that de novo mutations play an important role in severe male infertility and explain a portion of the genetic causes of this understudied disorder. To test this hypothesis, we utilize trio-based exome sequencing in a cohort of 185 infertile males and their unaffected parents. Following a systematic analysis, 29 of 145 rare (MAF < 0.1%) protein-altering de novo mutations are classified as possibly causative of the male infertility phenotype. We observed a significant enrichment of loss-of-function de novo mutations in loss-of-function-intolerant genes (p-value = 1.00 × 10−5) in infertile men compared to controls. Additionally, we detected a significant increase in predicted pathogenic de novo missense mutations affecting missense-intolerant genes (p-value = 5.01 × 10−4) in contrast to predicted benign de novo mutations. One gene we identify, RBM5, is an essential regulator of male germ cell pre-mRNA splicing and has been previously implicated in male infertility in mice. In a follow-up study, 6 rare pathogenic missense mutations affecting this gene are observed in a cohort of 2,506 infertile patients, whilst we find no such mutations in a cohort of 5,784 fertile men (p-value = 0.03). Our results provide evidence for the role of de novo mutations in severe male infertility and point to new candidate genes affecting fertility.publishersversionpublishe
A de novo paradigm for male infertility
Genetics of Male Infertility Initiative (GEMINI) consortium: Donald F. Conrad, Liina Nagirnaja, Kenneth I. Aston, Douglas T. Carrell, James M. Hotaling, Timothy G. Jenkins, Rob McLachlan, Moira K. O’Bryan, Peter N. Schlegel, Michael L. Eisenberg, Jay I. Sandlow, Emily S. Jungheim, Kenan R. Omurtag, Alexandra M. Lopes, Susana Seixas, Filipa Carvalho, Susana Fernandes, Alberto Barros, João Gonçalves, Iris Caetano, Graça Pinto, Sónia Correia, Maris Laan, Margus Punab, Ewa Rajpert-De Meyts, Niels Jørgensen, Kristian Almstrup, Csilla G. Krausz & Keith A. Jarvi.De novo mutations are known to play a prominent role in sporadic disorders with reduced fitness.
We hypothesize that de novo mutations play an important role in severe male infertility and
explain a portion of the genetic causes of this understudied disorder. To test this hypothesis, we
utilize trio-based exome sequencing in a cohort of 185 infertile males and their unaffected parents.
Following a systematic analysis, 29 of 145 rare (MAF < 0.1%) protein-altering de novo mutations
are classified as possibly causative of the male infertility phenotype. We observed a significant
enrichment of loss-of-function de novo mutations in loss-of-function-intolerant genes (p-value =
1.00 × 10−5) in infertile men compared to controls. Additionally, we detected a significant
increase in predicted pathogenic de novo missense mutations affecting missense-intolerant genes
(p-value = 5.01 × 10−4) in contrast to predicted benign de novo mutations. One gene we identify,
RBM5, is an essential regulator of male germ cell pre-mRNA splicing and has been previously
implicated in male infertility in mice. In a follow-up study, 6 rare pathogenic missense mutations
affecting this gene are observed in a cohort of 2,506 infertile patients, whilst we find no such
mutations in a cohort of 5,784 fertile men (p-value = 0.03). Our results provide evidence for the
role of de novo mutations in severe male infertility and point to new candidate genes affecting
fertility.This project was funded by The Netherlands Organization for Scientific Research (918-15-667) to J.A.V. as well as an Investigator Award in Science from the Wellcome Trust (209451) to J.A.V. a grant from the Catherine van Tussenbroek Foundation to M.S.O. a grant from MERCK to R.S. a UUKi Rutherford Fund Fellowship awarded to B.J.H. and the German Research Foundation Clinical Research Unit “Male Germ Cells” (DFG, CRU326) to C.F. and F.T. This project was also supported in part by funding from the Australian National Health and Medical Research Council (APP1120356) to M.K.O.B., by grants from the National Institutes of Health of the United States of America (R01HD078641 to D.F.C. and K.I.A., P50HD096723 to D.F.C.) and from the Biotechnology and Biological Sciences Research Council (BB/S008039/1) to D.J.E.info:eu-repo/semantics/publishedVersio
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