Desarrollo de tableros aglomerados compactos de cáscara de maní. Peanuts husks compact board development

El presente proyecto de investigación solicitado es continuacion de una línea de trabajo con insumos de desecho agroindustrial regional en la provincia de Cordoba. Prevé aportes que contribuyan a la sustentabilidad económica y social, y ambiental. Se trata de aportar valor agregado a importantes cantidades residuales de cascaras de mani. Además promueve la produccion de materiales y componentes de construcción de viviendas saludables y accesibles para sectores con necesidades sociohabitacionales.El deshecho de cáscara de maní constituye hoy en la provincia de Córdoba, un recurso sobre abundante no aprovechado en la escala en que se dispone. Existen desarrollos para su aprovechamiento - camadas de aves, alimento de ganado, carbon activado- , que no alcanzan a consumir las enormes cantidades de cascaras que se disponen hoy: alrededor de 250 000 Tn/ año. (La produccion anual de mani en caja en la provincia de Cordoba es estimada en 700.000 Tn/año)A partir de los resultados ya obtenidos con paneles livianos termoaislantes, utilizados en cielorrasos y tabiques divisorios, el nuevo trabajo de investigación y desarrollo se propone avanzar sobre las condiciones de produccion de tableros compactos, similares a los producidos comercialmente con residuos de la industria de la madera. Se estudiaran y experimentaran las propiedades de uso de resinas poliester, ureaformaldehido y fenolformaldehido, bajo condiciones de alta presion y temperatura. En la primera etapa (1º año) buscamos obtener nuevos materiales en escala de probetas.En una etapa siguiente (2º año), los nuevos materiales obtenidos serán aplicados al diseño de componentes de vivienda. Se estudiarán las posibilidades alternativas de empleo en relación a los parámetros de evaluación : peso, resistencia mecánica, aislación térmica, resistencia a la humedad, y al envejecimiento acelerado.En la última etapa (3º año) los resultados obtenidos serán aplicados en modelos de escala real y/o prototipos demostrativos para evaluar su puesta en servicio.

Mortalidade global e cardiovascular e fatores de risco de pacientes em hemodiálise

FUNDAMENTO: Mortalidade global e cardiovascular (CV) elevada de pacientes em hemodiálise. OBJETIVO: Avaliação da mortalidade global e CV e identificação do risco de pacientes em hemodiálise. MÉTODOS: Estudo observacional, prospectivo. Estudados 334 pacientes em três anos. Desfechos primários: mortalidade global e CV. Sobrevida avaliada pelo método de Kaplan-Meier. Identificação de variáveis de risco pela Regressão de Cox, bi e multivariada. RESULTADOS: Foram estudados 189 (56,6%) homens, idade 48,8 ± 14,2 anos, maioria de não brancos (295[88,3%]) e com escolaridade de 0 a menor que 8 anos (211[63,2%]). Mortalidade total de 21,6% (72/334), 50% sobrevivendo 146 meses, e mortalidade CV de 41,7%(30/72), 75% sobrevivendo 141 meses. Na análise bivariada, o RR de óbito não cardiovascular (ONCV) e CV aumentou com Idade >60 anos, Hb < 9,0 g/dl e glicemia de jejum >126 mg/dl; de ONCV apenas, com baixa escolaridade, viuvez, Hb<11,0 g/dl, Ht<33,0%, glicemia de jejum >100 mg/dl, produto Ca x P <42 e creatinina >9,2 mg/dl; diminuiu com PA>140/90 mmHg (antes da sessão de HD) e Ht>36%; de óbito CV apenas, aumentou com creatinina >9,4 mg/dl. Na análise multivariada, o RR de ONCV e CV aumentou com idade >60 anos e Hb<9 g/dl; o RR de óbito CV aumentou com glicemia>126 mg/dl e o de ONCV com taxa de remoção de ureia na hemodiálise (Kt/V) <1,2. CONCLUSÃO: A mortalidade global e CV de pacientes em hemodiálise é elevada. Os fatores de risco independentes para ONCV e CV foram idade >60 anos e Hb<9 g/dl, para óbito CV apenas glicemia >126 mg/dl e ONCV Kt/V<1,2. Vale assinalar a importância do monitoramento na correção e prevenção desses três últimos fatores.

An investigation into the temperature distribution resulting from cutting of compact bone using a reciprocating bone saw

Surgical procedures such as osteotomy and hip replacement involve the cutting of bone with the aid of various manual and powered cutting instruments including manual and powered bone saws. The basic mechanics of bone sawing processes are consistent with most other material sawing processes such as for wood or metal. Frictional rubbing between the blade of the saw and the bone results in the generation of localised heating of the cut bone. Research studies have been carried out which consider the design of the bone saw which deals with specifics of the saw teeth geometry and research which examines the effect of drilling operations on heating of the bone has shown that elevated temperatures will occur from frictional overheating. This overheating in localised areas is known to have an impact on the rate of healing of the bone post operation and the sharpness life of the blade. The purpose of this study was to measure the temperature at three zones at fixed intervals of 3mm, 6mm, and 9mm away from the cutting zone. It should be noted that it was the first time that this measurement technique was used to measure the temperature gradient through the bone specimen thereby establishing the extent to which clinicians are experiencing thermal injury during sawing of bone while using a reciprocating saw. The effect of various cutting feed rate on temperature elevation was also investigated in this research. The results showed that there will be a region of bone at least 9mm either side of the cutting blade experiencing thermal injury as temperatures in this region exceeded the threshold temperature of 44°C for necrosis (cell death).

Acoustic emission analysis of the effect of a 2D wedge shaped blade on the compact bone cutting process

Surgeons may use a number of cutting instruments such as osteotomes and chisels to cut bone during an operative procedure. The initial loading of cortical bone during the cutting process results in the formation of microcracks in the vicinity of the cutting zone with main crack propagation to failure occuring with continued loading. When a material cracks, energy is emitted in the form of Acoustic Emission (AE) signals that spread in all directions, therefore, AE transducers can be used to monitor the occurrence and development of microcracking and crack propagation in cortical bone. In this research, number of AE signals (hits) and related parameters including amplitude, duration and absolute energy (abs-energy) were recorded during the indentation cutting process by a wedge blade on cortical bone specimens. The cutting force was also measured to correlate between load-displacement curves and the output from the AE sensor. The results from experiments show AE signals increase substantially during the loading just prior to fracture between 90% and 100% of maximum fracture load. Furthermore, an amplitude threshold value of 64dB (with approximate abs-energy of 1500 aJ) was established to saparate AE signals associated with microcracking (41 – 64dB) from fracture related signals (65 – 98dB). The results also demonstrated that the complete fracture event which had the highest duration value can be distinguished from other growing macrocracks which did not lead to catastrophic fracture. It was observed that the main crack initiation may be detected by capturing a high amplitude signal at a mean load value of 87% of maximum load and unsteady crack propagation may occur just prior to final fracture event at a mean load value of 96% of maximum load. The author concludes that the AE method is useful in understanding the crack initiation and fracture during the indentation cutting process.

Preditores de função ventricular esquerda global na síndrome metabólica

FUNDAMENTO: A síndrome metabólica (SM) representa um conjunto de fatores de risco cardiovascular que agem de forma sinérgica. OBJETIVO: O objetivo desse estudo foi determinar quais parâmetros estavam associados de forma independente à função global do ventrículo esquerdo (VE) em indivíduos com SM, estimada através do índice Tei. MÉTODOS: O estudo incluiu 234 indivíduos com SM e 96 controles ajustados por idade. A SM foi definida pela presença de três ou mais critérios da ATP-NCEP III. Todos os indivíduos foram submetidos a testes laboratoriais e ecocardiograma bidimensional e com Doppler pulsátil e tecidual. Intervalos de tempo apropriados no Doppler tecidual para a estimativa do índice Tei também foram avaliados. RESULTADOS: O índice Tei estava aumentado em todos os indivíduos com SM (0,35 ± 0,05 vs 0,49 ± 0,10, p < 0,001). Análise de regressão múltipla dos parâmetros clínicos mostrou que a pressão arterial sistólica (β= 0,289, p < 0,001), glicemia de jejum (β= 0,205, p = 0,009), índice de massa do VE (β= 0,301, p < 0,001), E/e'septal (β= 0,267, p < 0,001) e e'septal (β= -0,176, p = 0,011) estavam independentemente associados com a função ventricular esquerda global estimada pelo índice Tei. CONCLUSÃO: A SM teve um impacto significante na função global do VE. A pressão arterial sistólica, glicemia de jejum, índice de massa do VE E/e'septal, e e'septal estavam independentemente associados com a função global do VE.

Hábitos Alimentares, Atividade Física e Escore de Risco Global de Framingham na Síndrome Metabólica

Fundamento: A síndrome metabólica é um transtorno complexo representado por um conjunto de fatores de risco cardiovascular. A adoção de um estilo de vida saudável está fortemente relacionada à melhora da Qualidade de Vida e interfere de forma positiva no controle dos fatores de risco presentes nessa condição clínica. Objetivo: Avaliar o efeito de um programa de modificação do estilo de vida sobre o Escore de Risco Cardiovascular Global de Framingham em indivíduos com síndrome metabólica. Método: Trata-se de uma subanálise de um ensaio clínico randomizado, controlado, cegado, com duração de três meses. Os participantes foram randomizados em quatro grupos: intervenção nutricional + placebo (INP), intervenção nutricional + suplementação de ácidos graxos ômega 3 (3 g/dia de óleo de peixe) (INS3), intervenção nutricional + atividade física + placebo (INEP) e intervenção nutricional + atividade física + suplementação de ácidos graxos ômega 3 (INES3). O Escore de Risco Cardiovascular Global de Framingham de cada indivíduo foi calculado antes e após a intervenção. Resultados: Participaram do estudo 70 indivíduos. Observou-se uma redução da média do escore após a intervenção de forma geral (p < 0,001). Obteve-se uma redução para risco intermediário em 25,7% dos indivíduos. Após a intervenção, observou-se redução significativa (p < 0,01) da "idade vascular", sendo esta mais expressiva nos grupos INP (5,2%) e INEP (5,3%). Conclusão: Todas as intervenções propostas produziram efeito benéfico para a redução do escore de risco cardiovascular. O presente estudo reforça a importância da modificação do estilo de vida na prevenção e no tratamento das doenças cardiovasculares.

On the provision of global public goods : experimental evidence on climate change mitigation issues

Magdeburg, Univ., Fak. für Wirtschaftswiss., Diss., 2011

Analysis, design, optimization and realization of compact high performance printed RF filters

Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2010

Collaboration process design for ideation in distributed environments : approaches to support collaborative ideation in global virtual groups using technological support

Magdeburg, Univ., Fak. für Informatik, Diss., 2012

power network concept : a theoretical and empirical approach to strategy in the global network economy

Magdeburg, Univ., Fak. für Wirtschaftswiss., Diss., 2014

Determinants of global color-based attention : insights from electromagnetic brain recording in humans

Otto-von-Guericke-Universität Magdeburg, Fakultät für Naturwissenschaften, Univ., Dissertation, 2015

Global literature of fiddler crabs, genus Uca (Decapoda, Ocypodidae): trends and future directions

Crabs of the genus Uca Leach, 1814 are characterized by having strong sexual dimorphism and a global distribution. Currently, 97 species have been described and analyzed under several aspects, including population ecology, physiology and ethology. However, there is no general summary of the information from the various literatures. The aim of this study is to perform a scientometric analysis of fiddler crab studies. For this we searched papers available in the Thomson ISI database that contained the words "Uca" OR "fiddler* crab*" between the years 1991 and 2007. For each paper, we researched and recorded the following characteristics: publication year; journal of publication; the first author's nationality; the country where the study was conducted; study type; species studied; and the work area. Our results indicated that there was no increase in the number of articles through the years considered. The Journal of Experimental Marine Biology and Ecology published most of the articles on Uca, indicating the importance of this group as a model for testing ecological hypotheses using experimental approaches. Our results also showed that United States had the highest number of authors and published studies on Uca, following the overall trend in dominance on scientific research. Furthermore, using models with three variables (per capita income, number of species of Uca and extent of coastal countries) we observed that, according to the Akaike Information Criterion, the per capita income was the most important correlate for the number of articles per country (both the author's country and country of study). Additionally, our results show that the species U. pugilator (distributed on the East Coast of the North American continent) was the species most singularly referenced in the papers considered. Moreover, our results indicate that most studies on Uca use a descriptive and local scale. The majority of papers in our literature search reflect studies in population biology, followed by behavioral and physiological characteristics.

The Phenomenon of international new ventures, global start-ups, and born-globals: what do we know after a decade (1993-2002) of exhaustive scientific inquiry?

In this paper, 27 studies from the last decade which deal more or less explicitly with the International New Venture, global start-up or born-global phenomenon are first identified, and then fully examined and critically assessed as a basis for obtaining an adequate view of the state-of-the-art of this increasingly important research avenue in the field of International Entrepreneurship (IE). The methodology used for this synthetic review allow us to analyze a number of recent, purposefully-chosen studies that are systematically compared along the following criteria: 1) main objective and type of research; 2) theoretical framework/s of reference, 3) methodological issues, and 4) main findings and/or conclusions. As a result of this literature review, a critical assessment follows in which the most relevant benefits and contributions as well as potential drawbacks, limitations or major discrepancies in the research activities conducted so far are discussed. Finally, some suggestions and implications are provided in the form of future research directions.

Global eriodicity and complete integrability of discrete dynamical systems

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