4,271 research outputs found

    Aplicação de sistema baseado em bainhas de pré-esforço ventiladas para redução do risco de fissuração de origem térmica do betão nas primeiras idades

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    A gestão do risco de fissuração de origem térmica durante as primeiras idades do betão é frequentemente a razão para que sejam adotados critérios conservativos no que diz respeito às alturas de betonagem a adotar em estruturas de grande volume. Por outro lado, a adoção de sistemas de pré ou pós-arrefecimento do betão para diminuir os efeitos do calor de hidratação acarreta normalmente consequências práticas e económicas que dificultam a sua aplicabilidade na generalidade das estruturas que poderiam beneficiar dessas técnicas. No presente artigo são estudados os efeitos da aplicação de um sistema de pós-arrefecimento do betão, com implementação acessível, baseado em bainhas de pré-esforço ventiladas, para redução do risco de fissuração na parede central de um descarregador de cheias. Em paralelo com a aplicação do sistema de arrefecimento foi efetuada uma caracterização térmica e mecânica do betão utilizado, bem como monitorização in-situ das temperaturas e extensões ocorridas. Adicionalmente foi efetuada uma simulação termo-mecânica para apoiar a compreensão dos efeitos do sistema de arrefecimento. Finalmente, com base nos trabalhos efetuados, são discutidas as limitações e possibilidades de aplicação prática desta técnica de arrefecimento

    Separate and combined effects of cyclic fasting and l-carnitine supplementation in red porgy (Pagrus pagrus, L. 1758)

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    We examined the e¡ects of cyclic fasting in red porgy (Pagrus pagrus) fed di¡erent dietary carnitine levels. Ju venile ¢sh (23.58 3.49 g) were divided into eight groups ^ four groups were fed every day to apparent sa tiation, while the other four were fasted for 7 days every 2 weeks. In each feeding regime, two replicates were fed an L-carnitine non-supplemented diet (46 mg kg 1 ) and the other two groups were fed an L-carnitine sup plemented diet (630 mg kg 1 ). Fish fed 630 mg L-carni tine accumulated two times more L-carnitine in muscle than ¢sh fed 46 mg L-carnitine. Cyclic fasting reduced the growth performance and lipid content in the liver. Carnitine supplementation did not a¡ect performance and body composition, but decreased the n-6 PUFA content. Moreover, the combined e¡ects of fasting and carnitine supplementation were observed on reducing the n-3 fatty acid content. Areas of steatosis were found in the livers of red porgy, but the results revealed that supplementation of L-carnitine in cyclic fasted ¢sh con tributed towards a lower degree of vacuolization than in ¢sh fed to apparent satiation. Regardless of the feed ing regime applied, the spleen of ¢sh fed the L-carni tine-supplemented diet was haemorrhagic and hyper activation of melanomacrophage cells was observed.info:eu-repo/semantics/publishedVersio

    Fibre Reinforced Polymer (FRP) connectors for Steel Fibre Reinforced Self-Compacting Concrete (SFRSCC) sandwich panels

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    Insulated sandwich wall panels are frequently composed of external concrete layers, mechanically connected through metallic connectors, such as trusses. Due to their high thermal conductivity, these connectors generally cause thermal bridges on the building envelope. In view of this problem, an innovative system is proposed where FRP connectors are used together with a thermal insulation layer. Steel Fibre Reinforced Self-Compacting Concrete (SFRSCC) wythes are also used to obtain panels that are both technically and economically advantageous. However, to present day there is no experimental data on the mechanical behaviour of the suggested connections. In this research, an experimental study is performed to characterize different types of FRP-SFRSCC connections under pull-out tests. Shear connection behaviour under monotonic loading is evaluated with slip controlled tests. Embedded and adhesively bonded connection solutions between SFRSCC layers and FRP connectors are studied.(undefined

    Autenticación mediante DNA barcoding de especies de meros legalmente protegidas y en peligro de extinción, sometidas a explotación pesquera, incluyendo el mero Goliat Epinephelus itajara

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    Fishing strategies are constantly changing to meet the needs for new or alternative food sources. Consequently, management of fishing activities regarding rates of exploitation is essential, as a number of resources have reached situations of overexploitation. The aim of the present study was to use DNA barcoding from the goliath grouper and other exploited epinephelids in order to provide procedures for DNA authentication to be used as evidence for combating putative illegal fishing. The species studied were Epinephelus adscensionis, Mycteroperca bonaci, Mycteroperca interstitialis, Epinephelus itajara, Mycteroperca venenosa, Epinephelus mystacinus, Dermatolepis inermis, Alphestes afer, Cephalopholis fulva, Mycteroperca acutirostris, Rypticus saponaceus, Mycteroperca marginata and Epinephelus morio. Four of these species are the main epinephelids fished in the Atlantic Ocean. Differential patterns of polymerase chain reaction–restriction fragment length polymorphism were obtained from the species and additional single nucleotide polymorphisms were also detected among the four main epinephelids studied. The procedures proved very efficient and we suggest their applicability to the other fish groups as a way to control illegal capture and retail around the world, especially in cases in which filleting and other forms of de-characterization cause a lack of morpho-anatomical key characters.Las estrategias de pesca cambian constantemente para satisfacer las necesidades de fuentes de alimento nuevas o alternativas. En consecuencia, a medida que los recursos alcanzan situaciones de sobreexplotación, resulta esencial establecer procedimientos de inspección de las actividades relacionadas con las tasas de explotación pesquera. El objetivo de este estudio es proponer el uso de la técnica de DNA barcoding para establecer la verificación de la identidad del mero Goliat y otros epinefélidos, a fin de utilizarlo como evidencia para combatir la pesca ilegal cuando se sospeche su ocurrencia. Las especies aquí estudiadas fueron Alphestes afer, Cephalopholis fulva, Dermatolepis inermis, Epinephelus adscensionis, E. itajara, E. morio, E. mystacinus, Mycteroperca acutirostris, M. bonaci, M. interstitialis, M. marginata, M. venenosa y Rypticus saponaceus de las cuales cuatro constituyen las más pescadas en el Océano Atlántico. Fueron encontrados patrones diferenciables de PCR-RFLPs para todas las especies y, además, fue posible detectar SNPs adicionales entre las cuatro especies más explotadas. Los procedimientos aquí empleados fueron muy eficaces por lo que sugerimos su aplicabilidad a otros grupos de peces como medida de control de la captura y comercialización ilegal a nivel mundial, particularmente en aquellos casos en los que el fileteado y otras formas de procesamiento que alteran las características anatómicas y morfológicas impiden su identificación

    The effects of different concentrations of the α2-Adrenoceptor Agonist Medetomidine on basal excitatory synaptic transmission and synaptic plasticity in hippocampal slices of adult mice

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    α2-Adrenoceptor agonists are used frequently in human and veterinary anesthesia as sedative/analgesic drugs. However, they can impair cognition. Little is known about the concentration-dependent effects of α2-adrenoceptor agonists on synaptic plasticity, the neurophysiological basis of learning and memory. Therefore, we investigated the effects of different concentrations of medetomidine, an α2-adrenoceptor agonist, on basal excitatory synaptic transmission and on 2 forms of synaptic plasticity: paired-pulse facilitation (PPF) and long-term potentiation (LTP).Funding: This work was supported by FCT (Lisbon, Portugal) and cofunded by COMPETE: 01-0124-FEDER-009497 (Lisbon, Portugal), through the project grants PTDC/CVT/099022/2008 and PTDC/SAU-NSC/122254/2010 and through a personal PhD grant (SFRH /BD/48883/2008) to Patrícia do Céu Oliveira Ribeiro and by QREN (09-68-ESR-FP-010).info:eu-repo/semantics/publishedVersio

    A Prediction Algorithm For Drug Response In Patients With Mesial Temporal Lobe Epilepsy Based On Clinical And Genetic Information

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Mesial temporal lobe epilepsy is the most common form of adult epilepsy in surgical series. Currently, the only characteristic used to predict poor response to clinical treatment in this syndrome is the presence of hippocampal sclerosis. Single nucleotide polymorphisms ( SNPs) located in genes encoding drug transporter and metabolism proteins could influence response to therapy. Therefore, we aimed to evaluate whether combining information from clinical variables as well as SNPs in candidate genes could improve the accuracy of predicting response to drug therapy in patients with mesial temporal lobe epilepsy. For this, we divided 237 patients into two groups: 75 responsive and 162 refractory to antiepileptic drug therapy. We genotyped 119 SNPs in ABCB1, ABCC2, CYP1A1, CYP1A2, CYP1B1, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, and CYP3A5 genes. We used 98 additional SNPs to evaluate population stratification. We assessed a first scenario using only clinical variables and a second one including SNP information. The random forests algorithm combined with leave-one-out cross-validation was used to identify the best predictive model in each scenario and compared their accuracies using the area under the curve statistic. Additionally, we built a variable importance plot to present the set of most relevant predictors on the best model. The selected best model included the presence of hippocampal sclerosis and 56 SNPs. Furthermore, including SNPs in the model improved accuracy from 0.4568 to 0.8177. Our findings suggest that adding genetic information provided by SNPs, located on drug transport and metabolism genes, can improve the accuracy for predicting which patients with mesial temporal lobe epilepsy are likely to be refractory to drug treatment, making it possible to identify patients who may benefit from epilepsy surgery sooner.121FAPESP [2013/07559-3]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Effect of different cleansers on the weight and ion release of removable partial denture: an in vitro study

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    OBJECTIVE: Removable partial dentures (RPD) require different hygiene care, and association of brushing and chemical cleansing is the most recommended to control biofilm formation. However, the effect of cleansers has not been evaluated in RPD metallic components. The aim of this study was to evaluate in vitro the effect of different denture cleansers on the weight and ion release of RPD. MATERIAL AND METHODS: Five specimens (12x3 mm metallic disc positioned in a 38x18x4 mm mould filled with resin), 7 cleanser agents [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) (control)] and 2 cobalt-chromium alloys [DeguDent (DD), and VeraPDI (VPDI)] were used for each experimental situation. One hundred and eighty immersions were performed and the weight was analyzed with a high precision analytic balance. Data were recorded before and after the immersions. The ion release was analyzed using mass spectrometry with inductively coupled plasma. Data were analyzed by two-way ANOVA and Tukey HSD post hoc test at 5% significance level. RESULTS: Statistical analysis showed that CT and MI had higher values of weight loss with higher change in VPDI alloy compared to DD. The solutions that caused more ion release were NaOCl and MI. CONCLUSIONS: It may be concluded that 0.05% NaOCl and Medical Interporous tablets are not suitable as auxiliary chemical solutions for RPD care
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