1,920 research outputs found
Psychosocial aspects of caregivers of children with cancer: stress and coping
O objetivo deste estudo foi avaliar o nível de stress dos cuidadores de crianças com leucemia, suas estratégias de enfrentamento, bem como caracterizar a vivência afetiva frente ao adoecimento. Participaram vinte cuidadores de crianças, após um ano de tratamento. Utilizaram-se os instrumentos: Inventário de Sintomas de Stress para Adultos de Lipp, Inventário de Estratégias de Coping e um roteiro complementar. Encontrou-se stress em 50% dos participantes, predominância na fase de resistência e sintomatologia psicológica. Renda superior esteve associada a manifestações de stress (p=0,02). As estratégias de enfrentamento mais utilizadas foram: "resolução de problemas" e "fuga e esquiva". Maior utilização da estratégia de enfrentamento "aceitação de responsabilidade" associou-se à presença de stress (p=0,04) e não ser praticante de religião (p=0,003). A análise da entrevista possibilitou o agrupamento em quatro categorias. Conclui-se que o cuidador necessita de atenção, visando melhorar a qualidade de vida e um maior acolhimento à criança.The purpose of this study was to assess the level of stress experienced by caregivers of children with leukemia, the coping strategies they use and to characterize the affective experience towards falling ill. Twenty caregivers participated in the study, which took place one year after the children began treatment. The following instruments were used: Lipp's Adult Stress Symptoms Inventory, Coping Strategy Inventory, and a supplementary script. It was found that 50% of the participants experienced stress, most were in the resistance phase and showed psychological symptoms. Higher income was associated with stress (p=0.02). The major coping strategies used were "problem solving" and "escape and avoidance". A greater use of the "acceptance of responsibility" strategy was associated with the presence of stress (p=0.04) and not practicing a religion (p=0.003). The analysis of the interviews enabled a grouping into four categories. In conclusion, the caregiver needs support with a view to improving his/herquality of life and to making children feel more welcome.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Robust bootstrap: an alternative to bootstrapping robust estimators
There is a vast literature on robust estimators, but in some situations it is still not easy to make inferences, such as confidence regions and hypothesis testing. This is mainly due to the following facts. On one hand, in most situations, it is difficult to derive the exact distribution of the estimator. On the other one, even if its asymptotic behaviour is known, in many cases, the convergence to the limiting distribution may be rather slow, so bootstrap methods are preferable since they often give better small sample results. However, resampling methods have several disadvantages including the propagation of anomalous data all along the new samples. In this paper, we discuss the problems arising in the bootstrap when outlying observations are present. We argue that it is preferable to use a robust bootstrap rather than to bootstrap robust estimators and we discuss a robust bootstrap method, the Influence Function Bootstrap denoted IFB. We illustrate the performance of the IFB intervals in the univariate location case and in the logistic regression model. We derive some asymptotic properties of the IFB. Finally, we introduce a generalization of the Influence Function Bootstrap in order to improve the IFB behaviour.Fil: Amado, Conceicao. Universidade de Lisboa; PortugalFil: Bianco, Ana Maria. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Boente Boente, Graciela Lina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santalo". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santalo"; ArgentinaFil: Pires, Ana M.. Universidade de Lisboa; Portuga
Penalized robust estimators in sparse logistic regression
Sparse covariates are frequent in classification and regression problems where the task of variable selection is usually of interest. As it is well known, sparse statistical models correspond to situations where there are only a small number of nonzero parameters, and for that reason, they are much easier to interpret than dense ones. In this paper, we focus on the logistic regression model and our aim is to address robust and penalized estimation for the regression parameter. We introduce a family of penalized weighted M-type estimators for the logistic regression parameter that are stable against atypical data. We explore different penalization functions including the so-called Sign penalty. We provide a careful analysis of the estimators convergence rates as well as their variable selection capability and asymptotic distribution for fixed and random penalties. A robust cross-validation criterion is also proposed. Through a numerical study, we compare the finite sample performance of the classical and robust penalized estimators, under different contamination scenarios. The analysis of real datasets enables to investigate the stability of the penalized estimators in the presence of outliers.Fil: Bianco, Ana Maria. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Calculo. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Calculo; ArgentinaFil: Boente Boente, Graciela Lina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; ArgentinaFil: Chebi, Gonzalo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Robust consistent estimators for ROC curves with covariates
The Receiver Operating Characteristic (ROC) curve is a use-ful tool to measure the classification capability of a continuous variable to assess the accuracy of a medical test that distinguishes between two conditions. Sometimes, covariates related to the diagnostic variable may increase the discriminating power of the ROC curve. Due to the lack of stability of classical ROC curves estimators to outliers, we introduce a procedure to obtain robust estimators in presence of covariates. The considered proposal focusses on a semiparametric approach which robustly fits a location-scale regression model to the diagnostic variable and considers robust adaptive empirical estimators of the regression residuals. The uniform consistency of the proposal is derived under mild assumptions. A Monte Carlo study is carried out to compare the performance of the robust proposed estimators with the classical ones both, in clean and contaminated samples. A real data set is also analysed.Fil: Bianco, Ana Maria. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Calculo. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Calculo; ArgentinaFil: Boente Boente, Graciela Lina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: González Manteiga, Wenceslao. Universidad de Santiago de Compostela; Españ
Las problemáticas de género en nuestra práctica profesional como psicológos
Objetivos del taller:
- Reflexionar acerca del impacto que en el ejercicio de nuestra profesión cobran la reproducción de las categorías diferenciales con las que en nuestra sociedad son pensados hombres y mujeres.
- Reconocer como el conocimiento de las problemáticas y categorías referidas al género amplían nuestra comprensión y tratamiento de los padeceres de hombres y mujeres.
- Transformar nuestra práctica con la inclusión de los desarrollos de género para pasar de ser meros reproductores de desigualdades y violencias a ser agentes promotores de nuevas construcciones subjetivas.TalleresFacultad de Psicologí
Las problemáticas de género en nuestra práctica profesional como psicológos
Objetivos del taller:
- Reflexionar acerca del impacto que en el ejercicio de nuestra profesión cobran la reproducción de las categorías diferenciales con las que en nuestra sociedad son pensados hombres y mujeres.
- Reconocer como el conocimiento de las problemáticas y categorías referidas al género amplían nuestra comprensión y tratamiento de los padeceres de hombres y mujeres.
- Transformar nuestra práctica con la inclusión de los desarrollos de género para pasar de ser meros reproductores de desigualdades y violencias a ser agentes promotores de nuevas construcciones subjetivas.TalleresFacultad de Psicologí
Las problemáticas de género en nuestra práctica profesional como psicológos
Objetivos del taller:
- Reflexionar acerca del impacto que en el ejercicio de nuestra profesión cobran la reproducción de las categorías diferenciales con las que en nuestra sociedad son pensados hombres y mujeres.
- Reconocer como el conocimiento de las problemáticas y categorías referidas al género amplían nuestra comprensión y tratamiento de los padeceres de hombres y mujeres.
- Transformar nuestra práctica con la inclusión de los desarrollos de género para pasar de ser meros reproductores de desigualdades y violencias a ser agentes promotores de nuevas construcciones subjetivas.TalleresFacultad de Psicologí
Effects of ezetimibe on markers of synthesis and absorption of cholesterol in high-risk patients with elevated C-reactive protein
AbstractAimsHigh-risk subjects with elevated C-reactive protein (CRP) are at high risk for cardiovascular events and frequently require potent statins or combined lipid-lowering therapy to achieve lipid targets and decrease inflammation. Our study aimed at evaluating the effects of three lipid-modifying therapies on LDL-cholesterol, CRP levels and markers of cholesterol absorption and synthesis.Main methodsA prospective intervention study was performed in high cardiovascular risk individuals receiving atorvastatin 10mg daily for four weeks. Those with CRP≥2.0mg/L were randomized to another four-week treatment period with atorvastatin 40mg, ezetimibe 10mg or the combination of atorvastatin 40mg / ezetimibe 10mg. Lipids, markers of cholesterol absorption (campesterol and β-sitosterol), and synthesis (desmosterol), as well as CRP were quantified at baseline and end of study.Key findingsOne hundred and twenty two individuals were included. Atorvastatin alone or combined with ezetimibe reduced both LDL-cholesterol and CRP (P<0.002 vs. baseline; Wilcoxon); ezetimibe did not modify CRP. Ezetimibe-based therapies reduced absorption markers and their ratios to cholesterol (P<0.0001 vs. baseline, for all; Wilcoxon), whereas atorvastatin alone increased campesterol/cholesterol and β-sitosterol/cholesterol ratios (P<0.05 vs. baseline; Wilcoxon). In addition, ezetimibe also increased desmosterol and desmosterol/cholesterol ratio (P<0.0001 vs. baseline; Wilcoxon).SignificanceThese results contribute to understanding the link between cellular cholesterol homeostasis, inflammation and lipid-modifying therapies. Our findings highlight the broader benefit of combined therapy with a potent statin and ezetimibe decreasing inflammation, and preventing increase in cholesterol biosynthesis, an effect not observed with ezetimibe alone
New Route for Valorization of Oil Mill Wastes: Isolation of Humic-Like Substances to be Employed in Solar-Driven Processes for Pollutants Removal
[EN] The valorization of olive oil mill solid wastes (OMW) has been addressed by considering it as a possible source of humic-like substances (HLSs), to be used as auxiliary substances for photo-Fenton, employing caffeine as a target pollutant to test the efficiency of this approach. The OMW-HLS isolation encompassed the OMW basic hydrolysis, followed by ultrafiltration and drying. OMW-HLS structural features have been investigated by means of laser light scattering, fluorescence, size exclusion chromatography, and thermogravimetric analysis; moreover, the capability of OMW-HLS to generate reactive species under irradiation has been investigated using spin-trap electronic paramagnetic resonance. The caffeine degradation by means of photo-Fenton process driven at pH = 5 was significantly increased by the addition of 10 mg/L of OMW-HLS. Under the mechanistic point of view, it could be hypothesized that singlet oxygen is not playing a relevant role, whereas other oxidants (mainly OH center dot radicals) can be considered as the key species in promoting caffeine degradation.Authors want to acknowledge the financial support of Spanish Ministerio de Economia y Competitividad (CTQ2015-69832-C04) and European Union (645551-RISE-2014, MAT4-TREAT).García-Ballesteros, S.; Grimalt, J.; Berto, S.; Minella, M.; Laurenti, E.; Vicente Candela, R.; López Pérez, MF.... (2018). New Route for Valorization of Oil Mill Wastes: Isolation of Humic-Like Substances to be Employed in Solar-Driven Processes for Pollutants Removal. ACS Omega. 3(10):13073-13080. https://doi.org/10.1021/acsomega.8b01816S130731308031
Recommended from our members
Role of B lymphocytes in the infarcted mass in patients with acute myocardial infarction
Despite early reperfusion, patients with ST segment elevation myocardial infarction (STEMI) may present large myocardial necrosis and significant impairment of ventricular function. The present study aimed to evaluate the role of subtypes of B lymphocytes and related cytokines in the infarcted mass and left ventricular ejection fraction obtained by cardiac magnetic resonance imaging performed after 30 days of STEMI. This prospective study included 120 subjects with STEMI submitted to pharmacoinvasive strategy. Blood samples were collected in subjects in the first (D1) and 30th (D30) days post STEMI. The amount of CD11b+ B1 lymphocytes (cells/ml) at D1 were related to the infarcted mass (rho = 0.43; P=0.033), measured by cardiac MRI at D30. These B1 cells were associated with CD4+ T lymphocytes at D1 and D30, while B2 classic lymphocytes at day 30 were related to left ventricular ejection fraction (LVEF). Higher titers of circulating IL-4 and IL-10 were observed at D30 versus D1 (P=0.013 and P<0.001, respectively). Titers of IL-6 at D1 were associated with infarcted mass (rho = 0.41, P<0.001) and inversely related to LVEF (rho = -0.38, P<0.001). After multiple linear regression analysis, high-sensitivity troponin T and IL-6 collected at day 1 were independent predictors of infarcted mass and, at day 30, only HDL-C. Regarding LVEF, high-sensitivity troponin T and high-sensitivity C-reactive protein were independent predictors at day 1, and B2 classic lymphocytes, at day 30. In subjects with STEMI, despite early reperfusion, the amount of infarcted mass and ventricular performance were related to inflammatory responses triggered by circulating B lymphocytes
- …