On unitarity of a linearized Yang-Mills formulation for massless and massive gravity with propagating torsion

A perturbative regime based on contortion as a dynamical variable and metric as a (classical) fixed background, is performed in the context of a pure Yang-Mills formulation for gravity in a $2+1$ dimensional space-time. In the massless case we show that the theory contains three degrees of freedom and only one is a non-unitary mode. Next, we introduce quadratical terms dependent on torsion, which preserve parity and general covariance. The linearized version reproduces an analogue Hilbert-Einstein-Fierz-Pauli unitary massive theory plus three massless modes, two of them represents non-unitary ones. Finally we confirm the existence of a family of unitary Yang-Mills-extended theories which are classically consistent with Einstein's solutions coming from non massive and topologically massive gravity. The unitarity of these YM-extended theories is shown in a perturbative regime. A possible way to perform a non-perturbative study is remarked.Comment: To appear in International Journal of Modern Physics

Pediculosis capitis en habitantes de una comunidad Indígena del estado Bolívar, Venezuela.

Pediculosis capitis is caused by Pediculus capitis, wingless insect that is specialized to live on the human scalp. This ectoparasitosis remains common today especially in children of school age and with socio sanitary deficiencies. The aim of this cross-sectional study, conducted in June 2014, was to determine the prevalence of head lice in people of the indigenous community “Itopoicon”, Bolívar State, Venezuela. After signing the informed consent, each participant filled a clinical epidemiological record and underwent an examination of the hair and scalp.La pediculosis capitis es producida por Pediculus capitis, un insecto áptero que se ha especializado a vivir en el cuero cabelludo humano. Esta ectoparasitosis sigue siendo común en la actualidad especialmente en niños en edad escolar y con deficiencias sociosanitarias. El objetivo de este estudio de tipo transversal, realizado en junio de 2014, fue determinar la prevalencia de pediculosis capitis en habitantes de la comunidad indígena “Itopoicon”, estado Bolívar, Venezuela. Previa firma del consentimiento informado, a cada participante se le llenó una ficha clínico-epidemiológica y se le realizó un examen del pelo y cuero cabelludo

An in vitro evaluation of standard rotational thromboelastography in monitoring of effects of recombinant factor VIIa on coagulopathy induced by hydroxy ethyl starch

BACKGROUND: Rotational thromboelastography (ROTEG) has been proposed as a monitoring tool that can be used to monitor treatment of hemophilia with recombinant factor VIIa (rFVIIa). In these studies special non-standard reagents were used as activators of the coagulation. The aim of this study was to evaluate if standard ROTEG analysis could be used for monitoring of effects of recombinant factor VIIa (rFVIIa) on Hydroxy Ethyl Starch-induced dilutional coagulopathy. METHODS: The study was performed in vitro on healthy volunteers. Prothrombin time (PT) and ROTEG analysis were performed after dilution with 33% hydroxy ethyl starch and also after addition of rFVIIa to the diluted blood. RESULTS: PT was impaired with INR changing from 0.9 before dilution to 1.2 after dilution while addition of rFVIIa to diluted blood lead to an overcorrection of the PT to an International Normalized Ratio (INR) value of 0.6 (p = 0.01). ROTEG activated with the contact activator ellagic acid was impaired by hemodilution (p = 0.01) while addition of rFVIIa had no further effects. ROTEG activated with tissue factor (TF) was also impaired by hemodilution (p = 0.01) while addition of rFVIIa lead to further impairment of the coagulation (p = 0.01). CONCLUSIONS: The parameters affected in the ROTEG analysis were Clot Formation Time and Amplitude after 15 minutes while the Clotting Time was unaffected. We believe these effects to be due to methodological problems when using standard activators of the coagulation in the ROTEG analysis in combination with rFVIIa

Lean manufacturing implementation proposal for small industries

The reduction of production costs has been widely used by companies as a way to increase their competitiveness. The Lean Manufacturing strategy accompanies this need in order to reduce waste in the production processes and, thus, increase the added value. Small companies differ from large companies because they have greater difficulties in introducing changes, associating concepts and accepting the need for transformation to remain competitive in the market. However, SMEs can also benefit from using the Lean methodology, which is a change of mindset, seeking customer satisfaction and reducing the cost generated by manufacturing process losses. The objective of this study was to develop a proposal for the implementation of Lean Manufacturing applicable to small companies in the metalworking sector, thus creating an instrument that allows the implementation of these production practices. Thereby, a broad literature review carried out, in order to verify and analyze the main existing implementation methods, as well as to identify the most appropriate approaches and tools for the context of SMEs. The proposal consists of an implementation structure, based on papers found in the literature, and the pilot structure divided into some main phases: (i) pre-implementation; (ii) implementation and (iii) post-implementation. The pilot structure went through an evaluation process, where area specialists were able to evaluate and make considerations, resulting in a proposed structure. According to the contributions made by the specialists, the structure subdivided into stages according to the PDCA methodology. It was then partially applied in a case study accomplished in an aluminum cookware manufacturer, located in the southwest of Paraná. Through the application, it was possible to visualize a real situation, identifying existing problems and wastes, proposing actions and solutions to obtain continuous improvement within this context. The preliminary results show that the proposed structure has a feasibility of implantation in the company, thus being able to collaborate for the development of a Lean culture, improving its operations in general.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)A redução dos custos de produção vem sendo amplamente utilizada pelas empresas como forma de aumentar sua competitividade. A estratégia Lean Manufacturing acompanha essa necessidade visando reduzir desperdícios nos processos produtivos e, assim, aumentando o valor agregado. As empresas de pequeno porte se diferenciam das grandes empresas pois possuem maiores dificuldades para introduzir mudanças, associar conceitos e aceitar a necessidade de transformação para permanecerem competitivas no mercado. No entanto, as PME’s também podem se beneficiar com a utilização da metodologia Lean, que consiste em uma mudança de mentalidade, buscando a satisfação do cliente e a diminuição do custo gerado pelas perdas decorrentes dos processos de fabricação. O objetivo deste estudo foi desenvolver uma proposta de implementação do Lean Manufacturing aplicável às empresas de pequeno porte do setor metalmecânico, criando assim um instrumento que possibilite a implantação destas práticas de produção. Inicialmente foi realizada uma ampla revisão de literatura, com o propósito de constatar e analisar os principais métodos de implementação existentes, bem como identificar as abordagens e ferramentas mais apropriadas para o contexto das PME’s. A proposta consiste em uma estrutura de implementação baseada em trabalhos encontrados na literatura, onde a estrutura proposta se divide em algumas fases principais: (i) pré-implementação, (ii) implementação e (iii) pós-implementação. A estrutura proposta foi avaliada por especialistas da área que a subdividiram em etapas seguindo a metodologia PDCA. Após, uma estrutura final de análise foi aplicada em uma empresa fabricante de panelas de alumínio, localizada no sudoeste do Paraná. Diante de uma situação real, foi possível identificar problemas e desperdícios existentes, propondo medidas e soluções para a obtenção de melhoria contínua dentro desse contexto. Os resultados preliminares demonstraram que a estrutura final possui viabilidade de implantação na empresa, podendo colaborar para o desenvolvimento de uma cultura Lean capaz de aprimorar seus processos

Pediculosis capitis en habitantes de una comunidad Indígena del estado Bolívar, Venezuela.

La pediculosis capitis es producida por Pediculus capitis, un insecto áptero que se ha especializado a vivir en el cuero cabelludo humano. Esta ectoparasitosis sigue siendo común en la actualidad especialmente en niños en edad escolar y con deficiencias sociosanitarias. El objetivo de este estudio de tipo transversal, realizado en junio de 2014, fue determinar la prevalencia de pediculosis capitis en habitantes de la comunidad indígena “Itopoicon”, estado Bolívar, Venezuela. Previa firma del consentimiento informado, a cada participante se le llenó una ficha clínico-epidemiológica y se le realizó un examen del pelo y cuero cabelludo