912 resultados para Contribution margin


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The impact of effluent wastewaters from four different hospitals: a university (1456 beds), a general (350 beds), a pediatric (110 beds) and a maternity hospital (96 beds), which are conveyed to the same wastewater treatment plant (WWTP), was evaluated in the receiving urban wastewaters. The occurrence of 78 pharmaceuticals belonging to several therapeutic classes was assessed in hospital effluents and WWTP wastewaters (influent and effluent) as well as the contribution of each hospital in WWTP influent in terms of pharmaceutical load. Results indicate that pharmaceuticals are widespread pollutants in both hospital and urban wastewaters. The contribution of hospitals to the input of pharmaceuticals in urban wastewaters widely varies, according to their dimension. The estimated total mass loadings were 306 g d− 1 for the university hospital, 155 g d− 1 for the general one, 14 g d− 1 for the pediatric hospital and 1.5 g d− 1 for the maternity hospital, showing that the biggest hospitals have a greater contribution to the total mass load of pharmaceuticals. Furthermore, analysis of individual contributions of each therapeutic group showed that NSAIDs, analgesics and antibiotics are among the groups with the highest inputs. Removal efficiency can go from over 90% for pharmaceuticals like acetaminophen and ibuprofen to not removal for β-blockers and salbutamol. Total mass load of pharmaceuticals into receiving surface waters was estimated between 5 and 14 g/d/1000 inhabitants. Finally, the environmental risk posed by pharmaceuticals detected in hospital and WWTP effluents was assessed by means of hazard quotients toward different trophic levels (algae, daphnids and fish). Several pharmaceuticals present in the different matrices were identified as potentially hazardous to aquatic organisms, showing that especial attention should be paid to antibiotics such as ciprofloxacin, ofloxacin, sulfamethoxazole, azithromycin and clarithromycin, since their hazard quotients in WWTP effluent revealed that they could pose an ecotoxicological risk to algae.

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This paper reports a Scanning Electron Microscopy study of some samples from the leg 12, Deep Sea Drilling Project, sites 118 and 119. The chronostratigraphic distribution, the frequency of the species identified and the datation of the samples studied are presented. In accordance with the calcareous nannofossil zonation proposed by E. MARTINI (1971) the samples from site 118 are ascribed to the Upper Miocene while the samples from site 119 are located between the Lower (NN1) and the Upper Miocene (NN10).

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Onshore, the Piacenzianof the Mondego and Lower Tagus Tertiary basins comprises siliciclastic sediments deposited in shallow marine to continental environments. The outcrops of the deposits are relatively widespread in the Aveiro and Seuibal region. A lithostratigraphic synthesis based on the correlation of geological sections, is presented for the two basins. In general, the Piacenzian sediments display a regressive sucession. The Late Tortonian-Zanclean (?) confined drainage pattern changed at the beginning of Piazencian, to fluvial systems draining to the Atlantic, and capturing the drainage of the inner parts of the Hesperic Meseta. The Piacenzian sedimentary sequence post-dates one of the uprising phases during Neogene compression, recorded by a strong regional unconformity. Some local active faulting - as in Lousa, Rio Maior and Senibal- Pinhal Novo - allowed the local thickening of the sedimentary record. Later compressive tectonism continues to generate reverse faulting and diapiric reactivation, affecting those sediments. Currently, the Piacenzian deposits culminates the marginal piedmonts, widely eroded by the Quaternary fluvial dissection.

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The development and applications of thermoset polymeric composites, namely fibre reinforced plastics (FRP), have shifted in the last decades more and more into the mass market [1]. Despite of all advantages associated to FRP based products, the increasing production and consume also lead to an increasing amount of FRP wastes, either end-of-lifecycle products, or scrap and by-products generated by the manufacturing process itself. Whereas thermoplastic FRPs can be easily recycled, by remelting and remoulding, recyclability of thermosetting FRPs constitutes a more difficult task due to cross-linked nature of resin matrix. To date, most of the thermoset based FRP waste is being incinerated or landfilled, leading to negative environmental impacts and supplementary added costs to FRP producers and suppliers. This actual framework is putting increasing pressure on the industry to address the options available for FRP waste management, being an important driver for applied research undertaken cost efficient recycling methods. [1-2]. In spite of this, research on recycling solutions for thermoset composites is still at an elementary stage. Thermal and/or chemical recycling processes, with partial fibre recovering, have been investigated mostly for carbon fibre reinforced plastics (CFRP) due to inherent value of carbon fibre reinforcement; whereas for glass fibre reinforced plastics (GFRP), mechanical recycling, by means of milling and grinding processes, has been considered a more viable recycling method [1-2]. Though, at the moment, few solutions in the reuse of mechanically-recycled GFRP composites into valueadded products are being explored. Aiming filling this gap, in this study, a new waste management solution for thermoset GFRP based products was assessed. The mechanical recycling approach, with reduction of GFRP waste to powdered and fibrous materials was applied, and the potential added value of obtained recyclates was experimentally investigated as raw material for polyester based mortars. The use of a cementless concrete as host material for GFRP recyclates, instead of a conventional Portland cement based concrete, presents an important asset in avoiding the eventual incompatibility problems arisen from alkalis silica reaction between glass fibres and cementious binder matrix. Additionally, due to hermetic nature of resin binder, polymer based concretes present greater ability for incorporating recycled waste products [3]. Under this scope, different GFRP waste admixed polymer mortar (PM) formulations were analyzed varying the size grading and content of GFRP powder and fibre mix waste. Added value of potential recycling solution was assessed by means of flexural and compressive loading capacities of modified mortars with regard to waste-free polymer mortars.

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Coal contains trace elements and naturally occurring radionuclides such as 40K, 232Th, 238U. When coal is burned, minerals, including most of the radionuclides, do not burn and concentrate in the ash several times in comparison with their content in coal. Usually, a small fraction of the fly ash produced (2-5%) is released into the atmosphere. The activities released depend on many factors (concentration in coal, ash content and inorganic matter of the coal, combustion temperature, ratio between bottom and fly ash, filtering system). Therefore, marked differences should be expected between the by-products produced and the amount of activity discharged (per unit of energy produced) from different coal-fired power plants. In fact, the effects of these releases on the environment due to ground deposition have been received some attention but the results from these studies are not unanimous and cannot be understood as a generic conclusion for all coal-fired power plants. In this study, the dispersion modelling of natural radionuclides was carried out to assess the impact of continuous atmospheric releases from a selected coal plant. The natural radioactivity of the coal and the fly ash were measured and the dispersion was modelled by a Gaussian plume estimating the activity concentration at different heights up to a distance of 20 km in several wind directions. External and internal doses (inhalation and ingestion) and the resulting risk were calculated for the population living within 20 km from the coal plant. In average, the effective dose is lower than the ICRP’s limit and the risk is lower than the U.S. EPA’s limit. Therefore, in this situation, the considered exposure does not pose any risk. However, when considering the dispersion in the prevailing wind direction, these values are significant due to an increase of 232Th and 226Ra concentrations in 75% and 44%, respectively.

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A very important part of the globally produced energy is consumed in buildings, being an important share frequently used in the HVAC systems. These ones are increasing both in performance and in complexity, taking advantage from the use of the recent advances in mechanical and power electronic devices, particularly in the speed variation field. However the improved efficiency only occurs while the HVAC unit is working in the conditions specified by the manufacturer, otherwise the energy consumption raises to values considerably higher than the nominal ones. The adequate maintenance enforces the system to run on its nominal performance and the contrary has undesirable impact both in the performance and in the system expected life time. Therefore, HVAC field maintenance assumes a very important role in the global building sustainability concept. This work presents some results of an incorrect use of HVAC and the associated electric energy overconsumption that can assume values 50% higher than those that occur when the installation is operated according to the adequate maintenance plan.

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Dissertation presented to obtain the Ph.D degree in Biology.

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RESUMO: Fizemos uma análise da evolução do conceito de estigma, das suas correlações e das suas consequências e analisámos os instrumentos psicométricos utilizados para estudar experiências pessoais de estigma. Revimos os principais estudos de investigação sobre estigma em Portugal. Revimos, igualmente, os estudos relevantes utilizando o “Consumer Experiences of Stigma Questionnaire” (CESQ) e as propriedades psicométricas já documentadas. O nosso estudo teve como objetivos: explorar as experiências de estigma numa amostra portuguesa de pessoas com perturbação mental grave e contribuir para a documentação das propriedades psicométricas do “Consumer Experiences of Stigma Questionnaire” e para a validação da sua versão portuguesa. Fizemos um estudo transversal, descritivo e analítico, recolhemos dados sociodemográficos e clínicos e medimos as experiências de estigma e o funcionamento global. A frequência das respostas da secção de estigma foi semelhante à dos restantes estudos utilizando a CESQ. A frequência das respostas na secção de discriminação foi ligeiramente inferior à reportada noutros estudos. Verificámos a existência de uma associação entre a pontuação da subescala de discriminação, o sexo masculino e o facto de se viver na comunidade. A pontuação da subescala de discriminação está também correlacionada de forma positiva com o funcionamento global. Os alfas de Cronbach para a CESQ e para as suas subescalas foram considerados bons. Os coeficientes de correlação intraclasse foram igualmente considerados igualmente bons. Utilizando técnicas de análise fatorial, verificámos que a maior parte dos itens da CESQ se enquadrava em dois fatores, correspondendo sensivelmente às subescalas definidas previamente. Concluímos que o presente estudo explorou com sucesso a questão do estigma em Portugal, contribuindo em simultâneo para a validação do “Consumer Experiences of Stigma Questionnaire.--------------ABSTRACT: We reviewed the evolution of concept of stigma, its correlates and consequences, and analysed psychometric instruments that were used to study personal experiences of stigma. We provided an insight over research of stigma in Portugal. We reviewed relevant studies that use Consumer Experiences of Stigma Questionnaire and documented psychometric properties of this instrument. Our study aimed both to explore experiences of stigma in a Portuguese sample of people with severe mental illness and to contribute to the assessment of the psychometric properties of Consumer Experiences of Stigma Questionnaire and to the validation of its Portuguese translation. We performed a cross sectional descriptive and analytic study, collected socio-demographic data and measured experiences of stigma and global functioning. Frequency of responses regarding stigma section of CESQ matched previous studies using that scale. Frequency of responses in discrimination section was slightly lower than previously reported studies. We found an association between the discrimination score of CESQ and both male gender and living in the community. The discrimination score also positively correlated with global functioning. Cronbach alphas for CESQ and its subscales were good. Intraclass correlation coefficients for CESQ and stigma subscale were also good. Using factor analysis we found most of the items in CESQ would fit 2 factors, grossly corresponding to the previously defined subscales. We conclude that this study successfully explored stigma in Portugal, contributing in simultaneous to the validation of Consumer Experiences Questionnaire.

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This work aimed to contribute to drug discovery and development (DDD) for tauopathies, while expanding our knowledge on this group of neurodegenerative disorders, including Alzheimer’s disease (AD). Using yeast, a recognized model for neurodegeneration studies, useful models were produced for the study of tau interaction with beta-amyloid (Aβ), both AD hallmark proteins. The characterization of these models suggests that these proteins co-localize and that Aβ1-42, which is toxic to yeast, is involved in tau40 phosphorylation (Ser396/404) via the GSK-3β yeast orthologue, whereas tau seems to facilitate Aβ1-42 oligomerization. The mapping of tau’s interactome in yeast, achieved with a tau toxicity enhancer screen using the yeast deletion collection, provided a novel framework, composed of 31 genes, to identify new mechanisms associated with tau pathology, as well as to identify new drug targets or biomarkers. This genomic screen also allowed to select the yeast strain mir1Δ-tau40 for development of a new GPSD2TM drug discovery screening system. A library of unique 138 marine bacteria extracts, obtained from the Mid-Atlantic Ridge hydrothermal vents, was screened with mir1Δ-tau40. Three extracts were identified as suppressors of tau toxicity and constitute good starting points for DDD programs. mir1Δ strain was sensitive to tau toxicity, relating tau pathology with mitochondrial function. SLC25A3, the human homologue of MIR1, codes for the mitochondrial phosphate carrier protein (PiC). Resorting to iRNA, SLC25A3 expression was silenced in human neuroglioma cells, as a first step towards the engineering of a neural model for replicating the results obtained in yeast. This model is essential to understand the mechanisms of tau toxicity at the mitochondrial level and to validate PiC as a relevant drug target. The set of DDD tools here presented will foster the development of innovative and efficacious therapies, urgently needed to cope with tau-related disorders of high human and social-economic impact.

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Ce travail s'intéresse aux modalités d'émergence et d'institutionnalisation d'un nouveau régime de création artistique, plus connu sous le nom de «Nouveau cinéma suisse ».Dans les années 1960-1970, l'arrivée du Nouveau cinéma suisse a bouleversé les manières de faire du cinéma en Suisse et a attiré l'attention sur le septième art helvétique. Comment une innovation artistique parvient-elle à s'imposer ? Comment un consensus autour d'une nouvelle forme artistique et de son mode de production émerge et se stabilise-t-il ? Quel rôle jouent les acteurs et les institutions dans ce processus ? Enfin, quelles sont les relations entre cette situation en devenir et les oeuvres créées dans ces conditions ? Au delà dé ces interrogations, c'est un questionnement théorique, épistémologique qui a motivé cette recherche. A l'image de la sociologie elle-même, l'analyse sociologique de l'art a été traversée, ces dernières années, pas de nombreux débats. Trop souvent, la réflexion s'appuie - ou trébuche -sur des dichotomies convenues :analyse interne /externe de l'art, déterminisme /indétermination des acteurs, reflet /autonomie des oeuvres. Quels sont les outils et les approches que propose la discipline pour analyser un tel objet, quels enseignements peut-on titrer de leur mise à l'épreuve sur un cas concret ? Quel est le défi lancé par le Nouveau cinéma suisse à la sociologie de l'art ?Mais commençons par le début car le point initial de cette longue entreprise était en réalité tout autre.

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In the context of an autologous cell transplantation study, a unilateral biopsy of cortical tissue was surgically performed from the right dorsolateral prefrontal cortex (dlPFC) in two intact adult macaque monkeys (dlPFC lesioned group), together with the implantation of a chronic chamber providing access to the left motor cortex. Three other monkeys were subjected to the same chronic chamber implantation, but without dlPFC biopsy (control group). All monkeys were initially trained to perform sequential manual dexterity tasks, requiring precision grip. The motor performance and the prehension's sequence (temporal order to grasp pellets from different spatial locations) were analysed for each hand. Following the surgery, transient and moderate deficits of manual dexterity per se occurred in both groups, indicating that they were not due to the dlPFC lesion (most likely related to the recording chamber implantation and/or general anaesthesia/medication). In contrast, changes of motor habit were observed for the sequential order of grasping in the two monkeys with dlPFC lesion only. The changes were more prominent in the monkey subjected to the largest lesion, supporting the notion of a specific effect of the dlPFC lesion on the motor habit of the monkeys. These observations are reminiscent of previous studies using conditional tasks with delay that have proposed a specialization of the dlPFC for visuo-spatial working memory, except that this is in a different context of "free-will", non-conditional manual dexterity task, without a component of working memory.

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The identification of associations between interleukin-28B (IL-28B) variants and the spontaneous clearance of hepatitis C virus (HCV) raises the issues of causality and the net contribution of host genetics to the trait. To estimate more precisely the net effect of IL-28B genetic variation on HCV clearance, we optimized genotyping and compared the host contributions in multiple- and single-source cohorts to control for viral and demographic effects. The analysis included individuals with chronic or spontaneously cleared HCV infections from a multiple-source cohort (n = 389) and a single-source cohort (n = 71). We performed detailed genotyping in the coding region of IL-28B and searched for copy number variations to identify the genetic variant or haplotype carrying the strongest association with viral clearance. This analysis was used to compare the effects of IL-28B variation in the two cohorts. Haplotypes characterized by carriage of the major alleles at IL-28B single-nucleotide polymorphisms (SNPs) were highly overrepresented in individuals with spontaneous clearance versus those with chronic HCV infections (66.1% versus 38.6%, P = 6 × 10(-9) ). The odds ratios for clearance were 2.1 [95% confidence interval (CI) = 1.6-3.0] and 3.9 (95% CI = 1.5-10.2) in the multiple- and single-source cohorts, respectively. Protective haplotypes were in perfect linkage (r(2) = 1.0) with a nonsynonymous coding variant (rs8103142). Copy number variants were not detected. We identified IL-28B haplotypes highly predictive of spontaneous HCV clearance. The high linkage disequilibrium between IL-28B SNPs indicates that association studies need to be complemented by functional experiments to identify single causal variants. The point estimate for the genetic effect was higher in the single-source cohort, which was used to effectively control for viral diversity, sex, and coinfections and, therefore, offered a precise estimate of the net host genetic contribution.

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Beta-oxidation of the conjugated linoleic acid 9-cis,11-trans-octadecadienoic acid (rumenic acid) was analyzed in vivo in Saccharomyces cerevisiae by monitoring polyhydroxyalkanoate production in the peroxisome. Polyhydroxyalkanoate is synthesized by the polymerization of the beta-oxidation intermediates 3-hydroxyacyl-CoAs via a bacterial polyhydroxyalkanoate synthase targeted to the peroxisome. The amount of polyhydroxyalkanaote synthesized from the degradation of rumenic acid was found to be similar to the amount synthesized from the degradation of 10-trans,12-cis-octadecadienoic acid, oleic acid or 10-cis-heptadecenoic acid. Furthermore, the degradation of 10-cis-heptadecenoic acid was found to be unaffected by the presence of rumenic acid in the media. Efficient degradation of rumenic acid was found to be independent of the Delta(3,5),Delta(2,4)-dienoyl-CoA isomerase but instead relied on the presence of Delta(3),Delta(2)-enoyl-CoA isomerase activity. The presence of the unsaturated monomer 3-hydroxydodecenoic acid in polyhydroxyalkanoate derived from rumenic acid degradation was found to be dependent on the presence of a Delta(3),Delta(2)-enoyl-CoA isomerase activity. Together, these data indicate that rumenic acid is mainly degraded in vivo in S. cerevisiae through a pathway requiring only the participation of the auxiliary enzymes Delta(3),Delta(2)-enoyl-CoA isomerase, along with the enzyme of the core beta-oxidation cycle.