1,164 research outputs found
Electrodeposition of Zn-Mn alloys from recycling battery leach solutions in the presence of amines
The recovery of metal ions by electrodeposition from solutions resulting from
the lixiviation of spent Zn-MnO2 batteries was studied. It was attempted to
optimise the electrodeposition process, the selectivity of ion-separation, the
morphologic characteristics, and the anticorrosive and galvanic properties of
metallic deposits. The simultaneous deposition of zinc and manganese on
different ferrous substrates under various experimental conditions was tested.
This allowed us to access the efficiency of the electrodeposition, the morphology
and composition of the metallic deposits, as well as their performance as
galvanic coating layers. The effect of amine additives, namely, of methylamine
and ethylenediamine, on the properties of the coatings was also studied. It was
shown that the amines with buffering or passivating effects improve the
simultaneous deposition of Mn
Microstructural characterization and tribocorrosion behaviour of Al/Al3Ti and Al/Al3Zr FGMs
Al/Al3Ti and Al/Al3Zr functionally graded materials (FGMs) were manufactured through a centrifugal method from Al–5 mass % Ti and Al–5 mass % Zr, respectively. Applied centrifugal forces were 30, 60 and 120 G (units of gravity). Microstructural characterization was performed and the influence of the reinforcing phase on the tribocorrosion behaviour of the FGMs was investigated. An increase in both the particles volume fraction as well as their orientation in the outer regions of the FGMs was found as the applied centrifugal force increased. Better tribocorrosion behaviour was found in the samples containing the highest concentration of reinforcing particles. However the microstructure below the surface appears to influence the tribocorrosion behaviour.The authors gratefully acknowledge the financial support provided by "Tokai Region Nanotechnology Manufacturing Cluster in KNOWLEDGE CLUSTER INITIATIVE" by the Ministry of Education, Culture, Sports, Science and Technology of Japan. Acknowledgments are also due to "FCT", Portugal, through the project SFRH/BPD/5518/2001
Electrochemical routes for industrial synthesis
This review examines the reasons for increasing interest towards electrolyses by the chemical industry, reviews the electrochemical industries as most of them now exist, and provides a status report on the key technological advances which are occurring to meet present and future needs. Classical industries like those of chloroalkali, aluminium, p-aminophenol, adiponitrile, ethylene glycol, anthraquinone, perfluorinated products, glyoxylic acid and L-cysteine are initially covered. Considering the large amount of available publications in these topics of electrochemical engineering, the covered relevant information is treated at a scientific level, although in a simplified way. Then the paper deals with emerging inorganic and organic processes, e.g. electrosynthesis in ionic liquids and mediated electrochemical processes, and finishes by assessing what the future development trend might be given the electrochemical and non electrochemical competing influences. With this approach it is hoped to stimulate the interest of chemical engineers and scientists non-specialised in electrochemical routes, and to review some cutting edge research, particularly as far as electrosynthesis in ionic liquids is concerned
Hyperprolinemia as a clue in the diagnosis of a patient with psychiatric manifestations
Lately, microdeletions of the 22q region, responsible for DiGeorge syndrome or velocardiofacial syndrome, have been increasingly related to neuropsychiatric disorders including schizophrenia and bipolar disorder. These manifestations seem to be related to certain genes located in the hemideleted region such as the proline dehydrogenase (PRODH) and the catechol-o-methyltransferase (COMT) genes. We describe a teenager who started his adolescent psychiatric care presenting cognitive impairment, irritable mood and aggressive behaviour with schizophrenia-like symptoms that scored 153 in the Positive and Negative Symptoms Scale (PANSS) assessment. Worsening of symptoms when the patient was treated with valproic acid, and plasma aminoacids showing an increase in alanine and proline, suggested a mitochondrial involvement of the proline metabolic pathway. Mild dysmorphic features also suggested a possible 22q11 deletion syndrome that was confirmed. A mutation for Hyperprolinemia type I was also detected. Knowledge of the correct diagnosis was crucial for an adequate treatment.info:eu-repo/semantics/publishedVersio
Arsenic in Water Resources of the Southern Pampa Plains, Argentina
Confronted with the need for accessible sources of good quality water and in view of the fact that the threat to public health posed by arsenic occurs mainly through the ingestion of contaminated drinking water, the presence and distribution of arsenic was evaluated in the southern Pampa Plains of Bahía Blanca district in Argentina. The findings show variable concentrations of arsenic in a complex distribution pattern. Complementary information is provided on the behavior of the groundwater resource and its salinity in terms of dissolved ions. Groundwater is the most severely affected, 97% of the samples exceeding the guideline value for arsenic in drinking water as recommended by the WHO (Guidelines for Drinking Water Quality, 2004). and showing maximum concentrations of up to 0.30 mg/L. Informing those responsible for preventive medicine and alerting the community at large will facilitate measures to mitigate exposure and ensure the safety of drinking water
Bank vole prion protein extends the use of RT-QuIC assays to detect prions in a range of inherited prion diseases
The cerebrospinal fluid (CSF) real-time quaking-induced conversion assay (RT-QuIC) is an ultrasensitive prion amyloid seeding assay for diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) but several prion strains remain unexplored or resistant to conversion with commonly used recombinant prion protein (rPrP) substrates. Here, bank vole (BV) rPrP was used to study seeding by a wide range of archived post-mortem human CSF samples from cases of sporadic, acquired and various inherited prion diseases in high throughput 384-well format. BV rPrP substrate yielded positive reactions in 70/79 cases of sporadic CJD [Sensitivity 88.6% (95% CI 79.5-94.7%)], 1/2 variant CJD samples, and 9/20 samples from various inherited prion diseases; 5/57 non-prion disease control CSFs had positive reactions, yielding an overall specificity of 91.2% (95% CI 80.1-97.1%). Despite limitations of using post-mortem samples and our results' discrepancy with other studies, we demonstrated for the first time that BV rPrP is susceptible to conversion by human CSF samples containing certain prion strains not previously responsive in conventional rPrPs, thus justifying further optimisation for wider diagnostic and prognostic use
As alterações ao Regulamento de Atribuição de Bolsas de Estudo no período de 2010 a 2015: O impacto na realidade da UTAD
O estudo pretende analisar o impacto das alterações ao regulamento de atribuição das bolsas de estudos a estudantes do ensino superior, com especial enfoque na Universidade de Trás-os-Montes e Alto Douro (UTAD), no período compreendido entre o ano de 2010 a 2015. Modificações nos procedimentos de análise para a atribuição das bolsas de estudos são identificadas no estado da arte e trazem consequências para os estudantes que necessitam de garantias para verem atendidos os seus direitos no âmbito do acesso às políticas de apoio social no ensino superior. Propõe-se a construção de um quadro analítico sobre os motivos de indeferimento das
candidaturas à atribuição de bolsas de estudos e a sua influência sobre a taxa de cobertura, considerando o direito à formação superior no quadro da igualdade de oportunidades. Tendo como campo empírico os Serviços de Ação Social da Universidade de Trás-os-Montes e Alto Douro (SASUTAD) foi utilizada uma metodologia mista,
quantitativa e qualitativa. A metodologia quantitativa teve como material empírico dados secundários de séries
estatísticas longas (estatísticas oficiais). A análise qualitativa teve como procedimento a análise documental aos
documentos de gestão e a observação participante para contextualizar a intervenção dos assistentes sociais
vertidas através de relatórios de visitas domiciliárias e entrevistas a estudantes candidatos a bolsa de estudos.
Pretendemos que os resultados contribuam para a compreensão das consequências das alterações à regulamentação dos apoios sociais, sobretudo dos estudantes de grupos sociais vulneráveis, cujo apoio é
fundamental para a conclusão dos estudos no ensino superior.info:eu-repo/semantics/publishedVersio
Local Renal Circadian Clocks Control Fluid-Electrolyte Homeostasis and BP.
The circadian timing system is critically involved in the maintenance of fluid and electrolyte balance and BP control. However, the role of peripheral circadian clocks in these homeostatic mechanisms remains unknown. We addressed this question in a mouse model carrying a conditional allele of the circadian clock gene Bmal1 and expressing Cre recombinase under the endogenous Renin promoter (Bmal1(lox/lox)/Ren1(d)Cre mice). Analysis of Bmal1(lox/lox)/Ren1(d)Cre mice showed that the floxed Bmal1 allele was excised in the kidney. In the kidney, BMAL1 protein expression was absent in the renin-secreting granular cells of the juxtaglomerular apparatus and the collecting duct. A partial reduction of BMAL1 expression was observed in the medullary thick ascending limb. Functional analyses showed that Bmal1(lox/lox)/Ren1(d)Cre mice exhibited multiple abnormalities, including increased urine volume, changes in the circadian rhythm of urinary sodium excretion, increased GFR, and significantly reduced plasma aldosterone levels. These changes were accompanied by a reduction in BP. These results show that local renal circadian clocks control body fluid and BP homeostasis
REVIEW PAPER Inferred global connectivity of whale shark Rhincodon typus populations
Ten years have passed since the last synopsis of whale shark Rhincodon typus biogeography. While a recent review of the species' biology and ecology summarized the vast data collected since then, it is clear that information on population geographic connectivity, migration and demography of R. typus is still limited and scattered. Understanding R. typus migratory behaviour is central to its conservation management considering the genetic evidence suggesting local aggregations are connected at the generational scale over entire ocean basins. By collating available data on sightings, tracked movements and distribution information, this review provides evidence for the hypothesis of broad-scale connectivity among populations, and generates a model describing how the world's R. typus are part of a single, global meta-population. Rhincodon typus occurrence timings and distribution patterns make possible a connection between several aggregation sites in the Indian Ocean. The present conceptual model and validating data lend support to the hypothesis that R. typus are able to move among the three largest ocean basins with a minimum total travelling time of around 2-4 years. The model provides a worldwide perspective of possible R. typus migration routes, and suggests a modified focus for additional research to test its predictions. The framework can be used to trim the hypotheses for R. typus movements and aggregation timings, thereby isolating possible mating and breeding areas that are currently unknown. This will assist endeavours to predict the longer-term response of the species to ocean warming and changing patterns of human-induced mortality
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