Characterization of polypropylene–polyethylene blends by temperature rising elution and crystallization analysis fractionation

The introduction of single-site catalysts in the polyolefins industry opens new routes to design resins with improved performance through multicatalyst-multireactor processes. Physical combination of various polyolefin types in a secondary extrusion process is also a common practice to achieve new products with improved properties. The new resins have complex structures, especially in terms of composition distribution, and their characterization is not always an easy task. Techniques like temperature rising elution fractionation (TREF) or crystallization analysis fractionation (CRYSTAF) are currently used to characterize the composition distribution of these resins. It has been shown that certain combinations of polyolefins may result in equivocal results if only TREF or CRYSTAF is used separately for their characterization

Ill-defined causes of death in Brazil: a redistribution method based on the investigation of such causes

OBJETIVO: Propor método de redistribuição de causas mal definidas de óbito baseado na investigação dessas causas. MÉTODOS: Foram analisados os resultados das investigações dos óbitos notificados como causas mal definidas (CMD) do capítulo XVIII da Classificação Estatística Internacional de Doenças (CID-10), no Sistema de Informações de Mortalidade em 2010. Os coeficientes de redistribuição foram calculados segundo a distribuição proporcional das causas mal definidas reclassificadas após investigação em qualquer capítulo da CID-10, exceto o capítulo XVIII, e utilizados para redistribuir as causas mal definidas não investigadas e remanescentes, segundo sexo e idade. O coeficiente de redistribuição-CMD foi comparado com dois métodos usuais de redistribuição: a) coeficiente de redistribuição-Total, baseado na distribuição proporcional de todas as causas definidas notificadas; b) coeficiente de redistribuição-Não externas, similar ao anterior, com exclusão das causas externas. RESULTADOS: Dos 97.314 óbitos por causas mal definidas notificados em 2010, 30,3% foram investigados. Desses, 65,5% foram reclassificados em causas definidas após investigação. As doenças endócrinas, transtornos mentais e causas maternas tiveram representação maior entre as causas mal definidas reclassificadas, ao contrário das doenças infecciosas, neoplasias e doenças do aparelho geniturinário, com proporções maiores entre causas definidas notificadas. As causas externas representaram 9,3% das causas mal definidas reclassificadas. A correção das taxas de mortalidade pelos critérios coeficiente de redistribuição-Total e coeficiente de redistribuição-Não externas aumentou a magnitude das taxas por fator relativamente semelhante para a maioria das causas, ao contrário do coeficiente de redistribuição-CMD, que corrigiu as diferentes causas de óbito com pesos diferenciados. CONCLUSÕES: A distribuição proporcional de causas entre as causas mal definidas reclassificadas após investigação não foi semelhante à distribuição original de causas definidas. Portanto, a redistribuição das causas mal definidas remanescentes com base nas investigações permite estimativas mais adequadas do risco de mortalidade por causas específicas.OBJECTIVE: To propose a method of redistributing ill-defined causes of death (IDCD) based on the investigation of such causes. METHODS: In 2010, an evaluation of the results of investigating the causes of death classified as IDCD in accordance with chapter 18 of the International Classification of Diseases (ICD-10) by the Mortality Information System was performed. The redistribution coefficients were calculated according to the proportional distribution of ill-defined causes reclassified after investigation in any chapter of the ICD-10, except for chapter 18, and used to redistribute the ill-defined causes not investigated and remaining by sex and age. The IDCD redistribution coefficient was compared with two usual methods of redistribution: a) Total redistribution coefficient, based on the proportional distribution of all the defined causes originally notified and b) Non-external redistribution coefficient, similar to the previous, but excluding external causes. RESULTS: Of the 97,314 deaths by ill-defined causes reported in 2010, 30.3% were investigated, and 65.5% of those were reclassified as defined causes after the investigation. Endocrine diseases, mental disorders, and maternal causes had a higher representation among the reclassified ill-defined causes, contrary to infectious diseases, neoplasms, and genitourinary diseases, with higher proportions among the defined causes reported. External causes represented 9.3% of the ill-defined causes reclassified. The correction of mortality rates by the total redistribution coefficient and non-external redistribution coefficient increased the magnitude of the rates by a relatively similar factor for most causes, contrary to the IDCD redistribution coefficient that corrected the different causes of death with differentiated weights. CONCLUSIONS: The proportional distribution of causes among the ill-defined causes reclassified after investigation was not similar to the original distribution of defined causes. Therefore, the redistribution of the remaining ill-defined causes based on the investigation allows for more appropriate estimates of the mortality risk due to specific causes

Trypanosoma cruzi Epimastigotes Are Able to Store and Mobilize High Amounts of Cholesterol in Reservosome Lipid Inclusions

Reservosomes are lysosome-related organelles found in Trypanosoma cruzi epimastigotes. They represent the last step in epimastigote endocytic route, accumulating a set of proteins and enzymes related to protein digestion and lipid metabolism. The reservosome matrix contains planar membranes, vesicles and lipid inclusions. Some of the latter may assume rectangular or sword-shaped crystalloid forms surrounded by a phospholipid monolayer, resembling the cholesterol crystals in foam cells.Using Nile Red fluorimetry and fluorescence microscopy, as well as electron microscopy, we have established a direct correlation between serum concentration in culture medium and the presence of crystalloid lipid inclusions. Starting from a reservosome purified fraction, we have developed a fractionation protocol to isolate lipid inclusions. Gas-chromatography mass-spectrometry (GC-MS) analysis revealed that lipid inclusions are composed mainly by cholesterol and cholesterol esters. Moreover, when the parasites with crystalloid lipid-loaded reservosomes were maintained in serum free medium for 48 hours the inclusions disappeared almost completely, including the sword shaped ones.Taken together, our results suggest that epimastigote forms of T. cruzi store high amounts of neutral lipids from extracellular medium, mostly cholesterol or cholesterol esters inside reservosomes. Interestingly, the parasites are able to disassemble the reservosome cholesterol crystalloid inclusions when submitted to serum starvation

The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation