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We report a multiplex family with a GATA1 gene mutation responsible for a massive fetal cerebral hemorrhage occurring at 36 weeks. Two other stillbirth cousins presented with fetal hydrops and congenital hemochromatosis' phenotype at 37 and 12 weeks of gestation. Molecular screening revealed the presence of a c.613G>A pathogenic allelic variation in exon 4 of GATA1 gene in the 3 male siblings and their carrier mothers. The diagnosis of a GATA1 gene mutation may be suspected in cases of male fetuses with intracerebral bleeding, particularly if a history of prior fetal loss(es) and mild maternal thrombocytopenia are also present.  相似文献   
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The tanning industry is one of the largest environmental polluters due to high generation waste in all production processes, but the tanning is particularly worrisome due to the use of significant amounts of chromium. Cr is an element potentially toxic to both health and the environment, depending on the concentration and the oxidation state. Cr(VI) can come in contact with human skin when using leather goods, which can cause allergies and dermatitis, besides being carcinogenic. Considering that approximately 90% of the world production of leather is performed with Cr salts, the determination of this element in leather is necessary to avoid exposure to the risks that the element can provide. The main goal of this study was the development of an alternative analytical method for the determination of Cr in leathers (ovine and bovine leather tanned with Cr and vegetable tannin) using wavelength dispersive X-ray fluorescence (WDXRF) for direct solid analysis. Besides performing analysis of the chemical composition and determination of Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Ni, Pb, Sb, Sr, Ti, and Zn in leather by inductively coupled plasma optical emission spectrometry (ICP OES). Principal component analysis (PCA) was also used in the evaluation of the WDXRF and ICP OES data sets. WDXRF calibration models for Cr presented satisfactory figures of merit and the analysis of the leathers revealed an alarming concentration of total Cr in the samples reaching 21,353 mg kg?1.  相似文献   
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Achieving ethically responsible decisions is crucial for the success of biodiversity conservation projects. We adapted the ethical matrix, decision tree, and Bateson's cube to assist in the ethical analysis of complex conservation scenarios by structuring these tools so that they can implement the different value dimensions (environmental, social, and animal welfare) involved in conservation ethics. We then applied them to a case study relative to the decision-making process regarding whether or not to continue collecting biomaterial on the oldest of the two remaining northern white rhinoceroses (Ceratotherium simum cottoni), a functionally extinct subspecies of the white rhinoceros. We used the ethical matrix to gather ethical pros and cons and as a starting point for a participatory approach to ethical decision-making. We used decision trees to compare the different options at stake on the basis of a set of ethical desiderata. We used Bateson's cube to establish a threshold of ethical acceptability and model the results of a simple survey. The application of these tools proved to be pivotal in structuring the decision-making process and in helping reach a shared, reasoned, and transparent decision on the best option from an ethical point of view among those available.  相似文献   
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Environmental Science and Pollution Research - The port regions of the Amazon are subject to environmental impacts high shipping traffic. In October 2015, a cargo ship containing 5000 oxen sank in...  相似文献   
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Environmental Science and Pollution Research - This research aimed to determine the water-sediment interaction (partition coefficient Kd) of trace element (Cd, Cu, total Cr, Pb, and Zn) in tropical...  相似文献   
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Solid state polymerizations (SSP) and the kinetic behavior in melt state of l-lactide polymerizations employing magnesium stearate as catalyst were investigated. The solid state polymerizations were carried out in two steps where pre-polymers were first prepared in melt polymerizations at 180 °C and the subsequent post-polymerizations were performed around the Tc of polylactide (PLA). In order to find the initial SSP conditions, kinetic profiles of melt polymerizations of l-lactide with magnesium stearate were determined. According to the kinetics data the melt polymerizations were found to be first order with respect to lactide as evident from a linear relationship of logarithmic variations of l-lactide concentration versus time using catalyst/monomer ratios of 1:500 and 1:5,000. When the catalyst content is increased to 1:100 the relationship loses its linearity due to fast propagation in the early stages of the reaction. From the GPC data it can be noted that the molecular weight of PLA can be increased by 5–17 times under the conditions established for our SSP experiments. A comparison between the two step solid state polymerizations and already reported melt polymerizations using the same catalyst showed that SSP furnished polymers with much lower amount of polymer degradation.  相似文献   
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