Taxas de erros de tipos I e II de procedimentos não paramétricos alternativos à ANOVA com dois fatores para dados discretos

Usualmente, nas alternativas à ANOVA paramétrica com dois fatores as observações são substituídas pelas suas ordens. No estudo do desempenho destas alternativas apenas têm sido consideradas distribuições contínuas. Contudo, quando os dados provêm de distribuições discretas propiciam a existência de muitos empates. Neste trabalho, recorrendo a um estudo por simulação, estudamos as taxas de erro de tipo I e II de várias dessas alternativas. Foram considerados delineamentos equilibrados com 2 fatores e dados provenientes de distribuições discretas. Os testes WTS e USP foram os que mostraram ser liberais. Os testes L de Puri & Sen e de van der Waerden não mostraram ter um bom desempenho

Taxas de erros de tipos I e II de alternativas não paramétricas à ANOVA com dois fatores: comparação entre delineamentos equilibrados e desequilibrados com dados discretos

A existência de observações empatadas pode infuenciar o desempenho dos procedimentos não paramétricos alternativos à ANOVA com dois fatores. Para comparamos o desempenho destas alternativas consideramos delineamentos equilibrados e desequilibrados, e que os dados são provenientes de distribuições discretas. Os nossos resultados mostram que o desempenho dos testes é afectado pelo tipo de delineamento (equilibrado ou desequilibrado), pelos efeitos presentes no modelo e pelo tamanho dos efeitos, e pela dimensão da amostra

Pinus pinea (L.) nut and kernel productivity in relation to cone, tree and stand characteristics

Pinus pinea stands have been identified as one of the target species for agroforestry systems in Europe. Its fruit yield is of importance to the local development, especially in the Mediterranean basin, due to its highly nutritional kernels and its economic value. The objectives of this study were to analyze the relation between pine nut and kernel weight and its efficiencies in relation to cone and tree traits for different stand structures. The statistical analysis was carried out with correlation, multiple correlation analysis, hurdle-gamma regression, principal component and cluster analysis, with a dataset of about 3300 cones collected in four plots and 3 years. The results indicate that pine nut and kernel and its efficiencies depend on stand structure, year and tree characteristics. The principal component analysis and the cluster analysis enabled the identification of four groups of trees related to the pine nut and kernel efficiencies. The higher efficiencies per tree are attained in stands managed for fruit production, increasing with the decrease of the density

Mechanical versus manual harvest of Pinus pinea cones

Umbrella pine cone production is an important forest non-wood product in Portugal,especially in the region of Alcácer do Sal, where it plays an important role to the local development. Traditionally umbrella pine cones are manually harvested, increasing production costs and, above all, with very high accident risk to the workers. The development of equipment for mechanical harvesting started in Italy in the 1980's. Studies report different values for harvesting efficiency and tree damage, the latter in terms of immature cones and branches detached. In this study a trunk shaker was used to evaluate mechanical harvesting both in terms of efficiency and tree damage induced by trunk vibration. In comparison to the manual process, time required for mechanised harvesting was about 1/15th of the time. The results revealed a mechanical harvesting efficiency higher than 86% with negligible tree damage. Inter-annual harvest efficiency variability was also observed

Role of omega-6 fatty acid metabolism in cardiac surgery postoperative bleeding risk

Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine. This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.Cardiac surgery is frequently associated with significant postoperative bleeding. Platelet-dysfunction is the main cardiopulmonary bypass (CPB)-induced hemostatic defect. Not only the number of platelets decreases, but also the remaining are functionally impaired. Although lipid metabolism is crucial for platelet function, little is known regarding platelet metabolic changes associated with CPB-dysfunction. Our aim is to explore possible contribution of metabolic perturbations for platelet dysfunction after cardiac surgery. Design: Prospective cohort study. Setting: Tertiary academic cardiothoracic-surgery ICU. Patients: Thirty-three patients submitted to elective surgical aortic valve replacement. Interventions: Samples from patients were collected at three time points (preoperative, 6- and 24-hr postoperative). Untargeted metabolic analysis using high-performance liquid chromatography-tandem mass spectrometry was performed to compare patients with significant postoperative bleeding with patients without hemorrhage. Principal component analyses, Wilcoxon matched-pairs signed-rank tests, adjusted to FDR, and pairwise comparison were used to identify pathways of interest. Enrichment and pathway metabolomic complemented the analyses. Measurements and main results: We identified a platelet-related signature based on an overrepresentation of changes in known fatty acid metabolism pathways involved in platelet function. We observed that arachidonic acid (AA) levels and other metabolites from the pathway were reduced at 6 and 24 hours, independently from antiagreggation therapy and platelet count. Concentrations of preoperative AA were inversely correlated with postoperative chest tube blood loss but were not correlated with platelet count in the preoperative, at 6 or at 24 hours. Patients with significant postoperative blood-loss had considerably lower values of AA and higher transfusion rates. Values of postoperative interleukin-6 were strongly correlated with AA variability. Conclusions and relevance: Our observations suggest that an inflammatory-related perturbation of AA metabolism is a signature of cardiac surgery with CPB and that preoperative levels of AA may be more relevant than platelet count to anticipate and prevent postoperative blood loss in patients submitted to cardiac surgery with CPB.info:eu-repo/semantics/publishedVersio

Genetic Characterization of Human T-Cell Lymphotropic Virus Type 1 in Mozambique: Transcontinental Lineages Drive the HTLV-1 Endemic

Human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of Adult T-Cell Leukemia/Lymphoma (ATL), the Tropical Spastic Paraparesis/HTLV-1-associated Myelopathy (TSP/HAM) and other inflammatory diseases, including dermatitis, uveitis, and myositis. It is estimated that 2–8% of the infected persons will develop a HTLV-1-associated disease during their lifetimes, frequently TSP/HAM. Thus far, there is not a specific treatment to this progressive and chronic disease. HTLV-1 has means of three transmission: (i) from mother to child during prolonged breastfeeding, (ii) between sexual partners and (iii) through blood transfusion. HTLV-1 has been characterized in 7 subtypes and the geographical distribution and the clinical impact of this infection is not well known, mainly in African population. HTLV-1 is endemic in sub-Saharan Africa. Mozambique is a country of southeastern Africa where TSP/HAM cases were reported. Recently, our group estimated the HTLV prevalence among Mozambican blood donors as 0.9%. In this work we performed a genetic analysis of HTLV-1 in blood donors and HIV/HTLV co-infected patients from Maputo, Mozambique. Our results showed the presence of three HTLV-1 clusters within the Cosmopolitan/Transcontinental subtype/subgroup. The differential rates of HIV-1/HTLV-1 co-infection in the three HTLV-1 clusters demonstrated the dynamic of the two viruses and the need for implementation of control measures focusing on both retroviruses

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe