Mixture models for distance sampling detection functions

Funding: EPSRC DTGWe present a new class of models for the detection function in distance sampling surveys of wildlife populations, based on finite mixtures of simple parametric key functions such as the half-normal. The models share many of the features of the widely-used “key function plus series adjustment” (K+A) formulation: they are flexible, produce plausible shapes with a small number of parameters, allow incorporation of covariates in addition to distance and can be fitted using maximum likelihood. One important advantage over the K+A approach is that the mixtures are automatically monotonic non-increasing and non-negative, so constrained optimization is not required to ensure distance sampling assumptions are honoured. We compare the mixture formulation to the K+A approach using simulations to evaluate its applicability in a wide set of challenging situations. We also re-analyze four previously problematic real-world case studies. We find mixtures outperform K+A methods in many cases, particularly spiked line transect data (i.e., where detectability drops rapidly at small distances) and larger sample sizes. We recommend that current standard model selection methods for distance sampling detection functions are extended to include mixture models in the candidate set.Publisher PDFPeer reviewe

Infantile de novo primary antiphospholipid syndrome revealed by neonatal stroke

International audiencepas de résum

Combined low-carbohydrate diet and long-term exercise in hypoxia in type 2 diabetes: A randomized controlled trial protocol to assess glycemic control, cardiovascular risk factors and body composition

Background: Cardiovascular disease is the leading cause of mortality associated with diabetes, which is characterized by chronic hyperglycemia. Low-carbohydrate diet has gained popularity as an intervention in patients with type 2 diabetes mellitus, acting to improve glycemic profile and serum lipids. In its turn, exercise in hypoxia induces specific adaptations, mostly modulated via hypoxia-induced transcription factor signaling cascade, which increases with exposure to altitude, and promotes angiogenesis, glycogen supply, glucose tolerance, and raises GLUT-4 expression. Aim: Given that hyperglycemia decreases HIF-1 and it is better controlled when following a low-carbohydrate diet, this study aims to examine the hypothesis that a combination of both low-carbohydrate diet and chronic exercise in hypoxia in type 2 diabetes mellitus is associated with improved glycemic control and cardiovascular parameters, whose protocol is described. Methods: Patients with type 2 diabetes mellitus ( n=48) will be recruited and randomized into one of the three groups: (a) Control group: Control diet (low-fat and moderate-carbohydrate diet)+exercise in normoxia; (2) exercise in hypoxia group: Control diet+exercise in hypoxia; (3) intervention group: Low-carbohydrate diet (low-carbohydrate and high-fat diet)+exercise in hypoxia. Before and after 8 weeks of interventions, cardiopulmonary tests (Bruce protocol), body composition and blood pressure will be evaluated. Blood samples will be collected to measure hypoxia-induced transcription factor, C-reactive protein, glycemic and lipid profiles. Summary: This will be the first trial to examine the isolated and combined effect of chronic exercise in hypoxia and low-carbohydrate diet in type 2 diabetes mellitus. This trial will help to fill a significant research gap, guide future research and contribute to the combined nutrition and exercise approach to type 2 diabetes mellitus. </jats:p

Validation of the Subjective Happiness Scale in People with Chronic Kidney Disease

Objetivo: Validar as propriedades psicométricas da Subjective Happiness Scale (SHS) em pessoas com Doença Renal Crônica (DRC) em programa de hemodiálise. Método: Trata-se de um estudo metodológico. A amostra randomizada foi constituída por 171 pessoas com DRC submetida a hemodiálise em duas clinicas na região de Lisboa, Portugal. Os dados foram colhidos de maio a junho de 2015. Foram avaliadas as propriedades psicométricas: validade (construto, convergente e discriminativa), fidedignidade por meio da consistência interna (α de Cronbach) e estabilidade (Coeficiente de Correlação Intraclasse e Coeficiente de Correlação de Spearman-Brown). Resultados: Os resultados suportam a estrutura unifatorial, com uma confiabilidade (α=0,90). Além disso, esta escala está positivamente correlacionada com a Escala de Satisfação com a Vida (r=0,60; p<0,001), apoiando assim a sua validade de critério. Conclusões: A versão portuguesa da SHS é válida e reprodutível em pessoas com DRC.info:eu-repo/semantics/publishedVersio

Validación de la “Subjective Happiness Scale” en Personas con Enfermedad Renal Crónica

Objective: To explore the psychometric properties of the Subjective Happiness Scale (SHS) in patients with Chronic Kidney Disease (CKD) undergoing hemodialysis. Methods: This is a methodological study. The random sample included 171 patients with CKD under hemodialysis program in two clinics in the region of Lisbon, Portugal. Data was collected between May and June 2015. The following psychometric properties were evaluated: validity (construct, convergent and discriminant), reliability through internal consistency (Cronbach α) and stability (intraclass correlation coefficient and Spearman-Brown correlation coefficient). Results: The results support the unifactorial structure, with reliability (α = 0.90). In addition, this scale is positively correlated with the Satisfaction Life Scale (r = 0.60; p <0.001), supporting the validity criteria. Conclusions: The Portuguese version of the SHS is valid and reproducible in patients with CKD.info:eu-repo/semantics/publishedVersio

Higgs Messengers

We explore the consequences of the Higgs fields acting as messengers of supersymmetry breaking. The hidden-sector paradigm in the gauge mediation framework is relaxed by allowing two types of gauge-invariant, renormalizable operators that are typically discarded: direct coupling between the Higgses and supersymmetry breaking singlets, and Higgs-messenger mixing terms. The most important phenomenological consequence is a flavor-dependent shift in sfermion masses. This is from a one-loop contribution, which we compute for a general set of weak doublet messengers. We also study a couple of explicit models in detail, finding that precision electroweak constraints can be satisfied with a spectrum significantly different from that of gauge mediation.Comment: 20 pages, 5 figure

Gastric microbial community profiling reveals a dysbiotic cancer-associated microbiota

Objective Gastric carcinoma development is triggered by Helicobacter pylori. Chronic H. pylori infection leads to reduced acid secretion, which may allow the growth of a different gastric bacterial community. This change in the microbiome may increase aggression to the gastric mucosa and contribute to malignancy. Our aim was to evaluate the composition of the gastric microbiota in chronic gastritis and in gastric carcinoma. Design The gastric microbiota was retrospectively investigated in 54 patients with gastric carcinoma and 81 patients with chronic gastritis by 16S rRNA gene profiling, using next-generation sequencing. Differences in microbial composition of the two patient groups were assessed using linear discriminant analysis effect size. Associations between the most relevant taxa and clinical diagnosis were validated by real-time quantitative PCR. Predictive functional profiling of microbial communities was obtained with PICRUSt. Results The gastric carcinoma microbiota was characterised by reduced microbial diversity, by decreased abundance of Helicobacter and by the enrichment of other bacterial genera, mostly represented by intestinal commensals. The combination of these taxa into a microbial dysbiosis index revealed that dysbiosis has excellent capacity to discriminate between gastritis and gastric carcinoma. Analysis of the functional features of the microbiota was compatible with the presence of a nitrosating microbial community in carcinoma. The major observations were confirmed in validation cohorts from different geographic origins. Conclusions Detailed analysis of the gastric microbiota revealed for the first time that patients with gastric carcinoma exhibit a dysbiotic microbial community with genotoxic potential, which is distinct from that of patients with chronic gastritis.This research was supported by a Worldwide Cancer Research grant to CF and JCM (Reference 16-1352). RMF, JPM and IPR have fellowships from Fundacao para a Ciencia e a Tecnologia (FCT; SFRH/BPD/84084/2012, PD/BD/114014/2015 and SFRH/BD/110803/2015, respectively) through Programa Operacional Capital Humano (POCH) and the European Union. JPM's fellowship is in the framework of FCT's PhD Programme BiotechHealth (Ref PD/0016/2012). i3S-Instituto de Investigacao e Inovacao em Saude is funded by Fundo Europeu de Desenvolvimento Regional (FEDER) funds through the COMPETE 2020-Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through Fundacao para a Ciencia e a Tecnologia (FCT)/Ministerio da Ciencia, Tecnologia e Inovacao (POCI-01-0145-FEDER-007274)

Next-generation analysis of trypanosomatid genome stability and instability

No abstract available

Validation of the Personal Wellbeing Index in People with Chronic Kidney Disease

Objetivo: verificar las propiedades psicométricas del Índice de bien-estar personal (IBP) en personas con enfermedad renal crónica en programa de hemodiálisis. Método: Se trata de un estudio metodológico. La muestra aleatoria es constituida por 171 personas con Enfermedad Renal Crónica (ERC) sometida a hemodiálisis en dos clínicas en la región de Lisboa, Portugal. La recogida de datos fue realizada entre mayo y junio de 2015. Se evaluaron las propiedades psicométricas: validad (constructo, predictiva convergente, y discriminativa), confiabilidad por medio de la consistencia interna (α de Cronbach) y estabilidad (Coeficiente de Correlación de Spearman-Brown y Coeficiente de Correlación Intraclasse (CCI)). Resultados: El IBP presenta una dimensión ajustada a los datos. La satisfacción con la salud es lo que más contribuye para el IBP. Tiene validad convergente con Felicidad Subjetiva y Afecto Positivo y Afecto Negativo. Tiene poder discriminativo en la nacionalidad. El α Cronbach fue de 0,82. Teste Re-teste para cuestionario 0, 92 e CCI= 0,95, para entrevista 0,85 y CCI= 0,89. Conclusiones: La versión portuguesa del IBP es válida y reproducible en personas con ERC, tanto por cuestionario como por entrevista.info:eu-repo/semantics/publishedVersio

A Randomized Double-Blind Study Comparing the Efficacy and Safety of Orlistat Versus Placebo in Obese Patients with Mild to Moderate Hypercholesterolemia

INTRODUCTION: Obesity is a chronic disease and a serious health problem that leads to increased prevalence of diabetes, hypertension, dyslipidemia and gallbladder disease. OBJECTIVE: To evaluate the efficacy of orlistat for weight loss and improved lipid profile compared to placebo in obese patients with hypercholesterolemia, treated over a period of 6 months. METHODOLOGY: In a 6-month, multicenter (10 centers in Portugal), double-blind, parallel, placebo-controlled study, 166 patients, aged 18-65 years, body mass index (BMI) > or = 27 kg/m2, LDL cholesterol > 155 mg/dl, were randomized to a reduced calorie diet (600 kcal/day deficit) plus orlistat three times a day or placebo. Exclusion criteria included triglycerides > 400 mg/dl, severe cardiovascular disease, uncontrolled hypertension, type 1 or 2 diabetes under pharmacological treatment, and gastrointestinal or pancreatic disease. RESULTS: The mean difference in weight from baseline was 5.9% (5.6 kg) in the orlistat group vs. 2.3% (2.2 kg) in the placebo group. In the orlistat group 49% of patients achieved 5-10% weight loss and 8.8% achieved > 10%. The orlistat group showed a significant reduction in total and LDL cholesterol, with similar changes for HDL in both treatment groups. The frequency of gastrointestinal adverse events was slightly higher in the orlistat group than in the placebo group, leading to discontinuation in 7 patients. CONCLUSION: Treatment with orlistat plus a reduced calorie diet for 6 months achieved significant reductions in weight, BMI and lipid parameters