Multivariate Birnbaum-Saunders Distributions: Modelling and Applications

Since its origins and numerous applications in material science, the Birnbaum–Saunders family of distributions has now found widespread uses in some areas of the applied sciences such as agriculture, environment and medicine, as well as in quality control, among others. It is able to model varied data behaviour and hence provides a flexible alternative to the most usual distributions. The family includes Birnbaum–Saunders and log-Birnbaum–Saunders distributions in univariate and multivariate versions. There are now well-developed methods for estimation and diagnostics that allow in-depth analyses. This paper gives a detailed review of existing methods and of relevant literature, introducing properties and theoretical results in a systematic way. To emphasise the range of suitable applications, full analyses are included of examples based on regression and diagnostics in material science, spatial data modelling in agricultural engineering and control charts for environmental monitoring. However, potential future uses in new areas such as business, economics, finance and insurance are also discussed. This work is presented to provide a full tool-kit of novel statistical models and methods to encourage other researchers to implement them in these new areas. It is expected that the methods will have the same positive impact in the new areas as they have had elsewhere

Improved Likelihood Inference in Birnbaum-Saunders Regressions

The Birnbaum-Saunders regression model is commonly used in reliability studies. We address the issue of performing inference in this class of models when the number of observations is small. We show that the likelihood ratio test tends to be liberal when the sample size is small, and we obtain a correction factor which reduces the size distortion of the test. The correction makes the error rate of he test vanish faster as the sample size increases. The numerical results show that the modified test is more reliable in finite samples than the usual likelihood ratio test. We also present an empirical application.Comment: 17 pages, 1 figur

Fast venomic analysis of Crotalus durissus terrificus from northeastern Argentina

The complete knowledge of the toxins that make up venoms is the base for the treatment of snake accidents victims and the selection of specimens for the preparation of venom pools for antivenom production. In this work, we used a fast and direct venomics approach to identify the toxin families in the C.d. terrificus venom, a Southern American Neotropical rattlesnake. The RP-HPLC separation profile of pooled venom from adult specimens followed by mass spectrometry analysis revealed that C.d. terrificus’ venom proteome is composed of 12 protein families, which are unevenly distributed in the venom, e.g., there are few major proteins in the venom's composition phospholipase A2, serine proteinase, crotamine and L-amino acid oxidase. At the same time, the proteome analysis revealed a small set of proteins with low quantity (less than 1.5%), both enzymes (metaloprotease, phospholipase B and 5′-nucleotidase) and proteins (Bradykinin potentiating and C-type natriuretic peptides, C-type lectin convulxin and nerve growth factor). To sum up, this research is the first venomic report of C.d.terrificus venom from Argentina. This proved to be crotamine positive venom that has a lower metalloprotease content than C.d. terrificus venoms from other regions. This information could be used in the discovery of future pharmacological agents or targets in antivenom therapy.Fil: Fusco, Luciano Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Química Básica y Aplicada del Nordeste Argentino. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura. Instituto de Química Básica y Aplicada del Nordeste Argentino; ArgentinaFil: Neto, Emidio B.. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; BrasilFil: Francisco, Aleff F.. Instituto de Biociencias; BrasilFil: Alfonso, Jorge. Fundación Oswaldo Cruz; BrasilFil: Soares, Andreimar. Fundación Oswaldo Cruz; BrasilFil: Pimenta, Daniel C.. Governo do Estado de Sao Paulo. Secretaria da Saude. Instituto Butantan; BrasilFil: Leiva, Laura Cristina Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Química Básica y Aplicada del Nordeste Argentino. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura. Instituto de Química Básica y Aplicada del Nordeste Argentino; Argentin

ASSOCIAÇÃO ENTRE LOMBALGIA CRÔNICA E DEPRESSÃO

A lombalgia com duração superior a 7-12 semanas é considerada crônica. Essa condição é reconhecida como um problema comum e que demanda altos custos em todo o mundo. É comum em pacientes portadores de dores lombares crônicas, a presença de depressão, ansiedade e distúrbios do sono. Embora não esteja claro que lombalgia crônica seja a causa base de depressão, é clara a associação entre elas. Esse estudo tem como objetivo identificar a influência da lombalgia crônica para o desenvolvimento de depressão e a frequência em que ocorre depressão nesses pacientes. A metodologia escolhida foi a revisão integrativa. Ao todo nove artigos foram selecionados. Sete estudos comprovaram a existência da relação entre lombalgia crônica e depressão. Nesses estudos podem-se encontrar resultados que variam de 4% a 69,7%. A promoção de saúde e prevenção da instalação das patologias crônicas de coluna, através de medidas simples de educação da população é a melhor forma de prevenção da instalação do quadro crônico

Guidelines for the use of human immunoglobulin therapy in patients with primary immunodeficiencies in Latin America

Antibodies are an essential component of the adaptative immune response and hold long-term memory of the immunological experiences throughout life. Antibody defects represent approximately half of the well-known primary immunodeficiencies requiring immunoglobulin replacement therapy. In this article, the authors review the current indications and therapeutic protocols in the Latin American environment. Immunoglobulin replacement therapy has been a safe procedure that induces dramatic positive changes in the clinical outcome of patients who carry antibody defects.Fil: Condino Neto, A.. Universidade de Sao Paulo; BrasilFil: Costa Carvalho, B. T.. Universidade Federal de Sao Paulo; BrasilFil: Grumach, A. S.. No especifíca;Fil: King, A.. No especifíca;Fil: Bezrodnik, Liliana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez". Área de Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Oleastro, M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Leiva, L.. Louisiana Tech University; Estados UnidosFil: Porras, O.. Hospital Nacional de Ninos ˜ Dr Carlos Sáenz Herrera"; Costa RicaFil: Espinosa Rosales, F. J.. Instituto Nacional de Pediatría; MéxicoFil: Franco, J. L.. Universidad de Antioquia; ColombiaFil: Sorensen, R. U.. Universidad de La Frontera; Chil

Controlling Size in Multicellular Organs: Focus on the Leaf

In leaves, cells get larger as cell division decreases or the ploidy increases. This might seem a logical response, but the controls are more complicated

PARTICIPAÇÃO DO PACIENTE COM DORES CRÔNICAS NA CONSTRUÇÃO DA CONDUTA MÉDICA E ADESÃO AO TRATAMENTO

No tratamento de dores crônicas é difícil a definição de um modelo específico para abordagem terapêutica, sendo importante a avaliação individual de cada paciente com participação ativa do mesmo. No Brasil, ainda são escassos os estudos sobre a participação do indivíduo na construção da conduta. O presente estudo teve como objetivo avaliar a associação entre a adesão à terapêutica prescrita e o grau de participação dos doentes na construção da conduta médica. Cerca de 87,5% dos pacientes que abandonaram um tratamento não haviam participado da construção do mesmo, o que denota uma correlação positiva entre os a autonomia e a adesão ao tratamento (p=0,004). Apesar da maioria dos pacientes terem conhecimento sobre detalhes da sua doença, ainda está instalado um modelo não participativo, que institui somente ao médico a tomada de decisão, já que estes não são questionados pelo médico quanto as suas necessidades e dificuldades

Study of the sensitisation process of a duplex stainless steel (UNS 1.4462) by means of confocal microscopy and localised electrochemical techniques

When duplex stainless steels are heated, they can become sensitised and intermetallic phases can appear. In this work, samples of duplex stainless steel, UNS 1.4462, have been heated (850 degrees C for 1 and 2 h) in a heating unit that can be accommodated to a confocal microscope in order to study the morphological changes in-situ. The electrochemical behaviour of the samples has been analysed by means of conventional and localised electrochemical techniques. According to the results, there is a general decrease in the steel resistance to localised corrosion; this decrease can be related to defects in the formed passive film.We wish to express our gratitude to MICINN (CTQ2009-07518), to Universitat Politecnica de Valencia (CEI-01-11), to the Generalitat Valenciana for its help in the CLSM acquisition (MY08/ISIRM/S/100), to Professor Alda Simoes and Andreia Marques for the help on LEIS measurements and to Dr. Asuncion Jaime for her translation assistance.Leiva García, R.; Fernandes, JS.; Muñoz-Portero, M.; Garcia-Anton, J. (2015). Study of the sensitisation process of a duplex stainless steel (UNS 1.4462) by means of confocal microscopy and localised electrochemical techniques. Corrosion Science. 94:327-341. https://doi.org/10.1016/j.corsci.2015.02.016S3273419