Análisis comparativo desde una perspectiva energética, económica y medioambiental de instalaciones térmicas en viviendas unifamiliares para aporte de calefacción y ACS

Este informe contiene el trabajo de fin de máster de Telmo Fernandez Intxaurrandieta, estudiante del máster de Eficiencia Energética y Sostenibilidad en Industria, Transporte, Edificación y Urbanismo en la Universidad del País Vasco (UPV). El proyecto trata de hacer un análisis comparativo desde una perspectiva energética, económica y medioambiental de instalaciones térmicas en viviendas unifamiliares para aporte de calefacción y ACS. En el informe se muestra cómo se ha implementado un escenario de simulación de diferentes sistemas de calefacción y ACS utilizando la herramienta HULC y su posterior análisis energético, económico y medioambiental

Depression and Oral FTC/TDF Pre-exposure Prophylaxis (PrEP) Among Men and Transgender Women Who Have Sex With Men (MSM/TGW).

We conducted a longitudinal and cross-sectional analysis of depressive symptomology in iPrEx, a randomized, placebo-controlled trial of daily, oral FTC/TDF HIV pre-exposure prophylaxis (PrEP) in men and transgender women who have sex with men. Depression-related adverse events (AEs) were the most frequently reported severe or life-threatening AEs and were not associated with being randomized to the FTC/TDF arm (152 vs. 144 respectively OR 0.66 95 % CI 0.35-1.25). Center for Epidemiologic Studies Depression scale (CES-D) and a four questions suicidal ideation scale scores did not differ by arm. Participants reporting forced sex at anal sexual debut had higher CES-D scores (coeff: 3.23; 95 % CI 1.24-5.23) and were more likely to have suicidal ideation (OR 2.2; 95 % CI 1.09-4.26). CES-D scores were higher among people reporting non-condom receptive anal intercourse (ncRAI) (OR 1.46; 95 % CI 1.09-1.94). We recommend continuing PrEP during periods of depression in conjunction with provision of mental health services

Ultrasound-Guided Radiofrequency Ablation of Chemodectomas in Five Dogs

Chemodectomas are low prevalence tumors with complex clinical management. Many present as an incidental finding however, in other dogs, they produce pericardial effusion and/or compression, leading to the appearance of severe clinical signs. There are currently several approaches: surgery, radiotherapy, stent placement and chemotherapy. This is the first description of percutaneous echo-guided radiofrequency ablation of aortic body tumors. This minimally invasive treatment is based on high frequency alternating electrical currents from an electrode that produces ionic agitation and generates frictional heat, causing coagulation necrosis. Five dogs with an echocardiographic and cytological diagnosis of chemodectoma underwent percutaneous echo-guided radiofrequency ablation. At the time of presentation, all the dogs showed clinical signs, such as ascites and/or collapse. There were no complications either during the procedure or in the following 24 hours. Rapid clinical improvement associated with a reduction in size and change in sonographic appearance of the mass were achieved with no complications. Six months follow-up was carried out in all dogs. A second percutaneous echo-guided RFA was performed eight months after the first procedure in one dog. Based on our experience, radiofrequency ablation seems to be a feasible and safe technique, making it a potential alternative therapeutic approach in the clinical management of aortic body tumors leading to severe clinical compromise

Residual stress evaluation in friction stir welds of inconel 625

A utilização de materiais nobres é requisito básico em aplicações onde existe um ambiente agressivo como na indústria do petróleo e nuclear. Neste panorama, a liga Inconel 625 é frequentemente utilizada como material de cladeamento no revestimento interno de dutos rígidos. Assim, as superligas de níquel exercem papel fundamental nos campos de exploração de águas profundas e, por isso, o conhecimento de métodos modernos de soldagem aplicados a estas ligas e suas consequências nos estados de tensões residuais é importante. Portanto, o presente trabalho faz uma avaliação das tensões residuais após a Soldagem por Fricção e Mistura Mecânica (SFMM) em chapas soldadas de Inconel 625. A união das chapas foi realizada com rotação da ferramenta 200 e 1200 rpm e velocidade de soldagem constante (1mm/s). As medições de tensões residuais na superfície das juntas soldadas foram investigadas através da técnica de difração de raios-X. Além disso, foram avaliadas as macroestruturas e o aporte térmico de acordo com os parâmetros de soldagem empregados. Embora não existam muitos trabalhos relacionados ao processo SFMM para ligas de Inconel, provavelmente devido à sua dificuldade de soldagem, tem sido percebido um aumento na aplicação da soldagem no estado sólido como excelente alternativa para as superligas à base de níquel. Os resultados mostraram que diferentes parâmetros de processo produziram juntas soldadas distintas e, consequentemente, variações na distribuição de tensões residuais. Por fim, um aumento na velocidade de rotação da ferramenta ocasionou um aumento nas tensões residuais na zona de mistura.The use of noble materials is a basic requirement in applications where an aggressive environment such as offshore industry and nuclear energy. In this scenario, the Inconel 625 is often used as clad material in rigid pipes. Thus, nickel superalloys play a fundamental role in the deepwater exploration fields and, therefore, understanding of modern welding methods applied to these alloys and their consequences in the residual stress states is very important. Hence, this work evaluates the residual stress distributions after Friction Stir Welding (FSW) applied on Inconel 625 sheets. FSW was performed with tool rotational speed in the range of 200 to 1200 rpm and welding speed constant. Measurements of superficial residual stresses were investigated by X-ray Diffraction. In addition, macrostructures and heat input were evaluated. Although there are only few reports related to FSW applied on Inconel alloys, probably due to this welding process difficulty, it has been regarded that there is cumulative application of a solid state welding as an excellent alternative for nickel superalloys. The results showed that different welding parameters produced distinctly welded joints and consequently changes in the residual stress distributions. Finally, an increase in the tool rotation speed increased the residual stress in the stir zone

Syphilis Predicts HIV Incidence Among Men and Transgender Women Who Have Sex With Men in a Preexposure Prophylaxis Trial

Background. Syphilis infection may potentiate transmission of human immunodeficiency virus (HIV). We sought to determine the extent to which HIV acquisition was associated with syphilis infection within an HIV preexposure prophylaxis (PrEP) trial and whether emtricitabine/tenofovir (FTC/TDF) modified that association. Methods. The Preexposure Prophylaxis Initiative (iPrEx) study randomly assigned 2499 HIV-seronegative men and transgender women who have sex with men (MSM) to receive oral daily FTC/TDF or placebo. Syphilis prevalence at screening and incidence during follow-up were measured. Hazard ratios for the effect of incident syphilis on HIV acquisition were calculated. The effect of FTC/TDF on incident syphilis and HIV acquisition was assessed. Results. Of 2499 individuals, 360 (14.4%) had a positive rapid plasma reagin test at screening; 333 (92.5%) had a positive confirmatory test, which did not differ between the arms (FTC/TDF vs placebo, P = .81). The overall syphilis incidence during the trial was 7.3 cases per 100 person-years. There was no difference in syphilis incidence between the study arms (7.8 cases per 100 person-years for FTC/TDF vs 6.8 cases per 100 person-years for placebo, P = .304). HIV incidence varied by incident syphilis (2.8 cases per 100 person-years for no syphilis vs 8.0 cases per 100 person-years for incident syphilis), reflecting a hazard ratio of 2.6 (95% confidence interval, 1.6–4.4; P < .001). There was no evidence for interaction between randomization to the FTC/TDF arm and incident syphilis on HIV incidence. Conclusions. In HIV-seronegative MSM, syphilis infection was associated with HIV acquisition in this PrEP trial; a syphilis diagnosis should prompt providers to offer PrEP unless otherwise contraindicated

Friction stir spot welding of a TRIP steel : microestructural characterization

Este trabalho tem como objetivo investigar a influência da velocidade de rotação (1.600 RPM e 2.400 RPM) no desenvolvimento microestrutural de um aço TRIP soldado a ponto por fricção e mistura mecânica. Após a execução das soldas, devido aos ciclos térmicos e deformações impostas pelo processo, são observadas três diferentes zonas nas juntas: a zona de mistura (ZM), a zona termomecanicamente afetada (ZTMA), e a zona termicamente afetada (ZTA). O aumento da velocidade de rotação causou um aumento na quantidade de ferrita alotriomorfa formada na ZM, assim como redução na quantidade e tamanho de bainita coalescida e martensita. Na ZTMA a microestrutura é constituída por ferrita, austenita, bainita coalescida e martensita. Enquanto que na ZTA1 a microestrutura é composta por ferrita e austenita retida em todas as velocidades usadas, na ZTA2 há maior transformação da austenita em bainita com o aumento da velocidade de rotação.The aim of this work is to verify the influence of the rotational speed (1600 and 2400 RPM) in the microstructural development of a friction stir spot welded TRIP steel. After the welding, due to the thermal cycles and deformations imposed by the process, three different zones are observed in the joints: the stir zone (SZ), the thermomecanically affected zone (TMAZ), and the heat affected zone (HAZ). The increase in the rotational speed caused an increase in the amount of allotriomorphic ferrite formed in the SZ, and a decrease in the amount and width of the coalesced bainite and martensite. In the TMAZ, the microstructure is composed by ferrite, austenite, coalesced bainite and martensite. While in the HAZ1 the microstructure is constituted by ferrite and retained austenite in all rotational speeds employed, in the HAZ2 there is an increase in the transformation of austenite into bainite by increasing the rotational speed

Coordinated waves of actomyosin flow and apical cell constriction immediately after wounding

© 2013 Antunes et al. This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 3.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/3.0/).Epithelial wound healing relies on tissue movements and cell shape changes. Our work shows that, immediately after wounding, there was a dramatic cytoskeleton remodeling consisting of a pulse of actomyosin filaments that assembled in cells around the wound edge and flowed from cell to cell toward the margin of the wound. We show that this actomyosin flow was regulated by Diaphanous and ROCK and that it elicited a wave of apical cell constriction that culminated in the formation of the leading edge actomyosin cable, a structure that is essential for wound closure. Calcium signaling played an important role in this process, as its intracellular concentration increased dramatically immediately after wounding, and down-regulation of transient receptor potential channel M, a stress-activated calcium channel, also impaired the actomyosin flow. Lowering the activity of Gelsolin, a known calcium-activated actin filament-severing protein, also impaired the wound response, indicating that cleaving the existing actin filament network is an important part of the cytoskeleton remodeling process.info:eu-repo/semantics/publishedVersio

Boletín meteorológico diario: Número 80 - 1981 Marzo 21

Soldagem a ponto por fricção é um processo que ocorre no estado sólido com alta eficiência energética, baixo custo de produção além de ser um processo ambientalmente limpo. Estes processos por fricção são uma alternativa a processos convencionais tais como solda ponto por resistência, rebitamento e prensagem a frio. A ausência de uma fase de fusão nesses processos elimina defeitos como porosidades, bolhas, rebaixos, inclusões e microestruturas indesejáveis, que frequentemente aparecem na solda e zonas afetadas pelo calor em processos de soldagem por fusão. O processo de SPFMM consiste em uma ferramenta, que é uma combinação de um pino e um ombro que em rotação, penetra nas chapas formando uma junta sobreposta. O contato do pino com regiões adjacentes e do ombro com a superfície superior da junta geram calor de fricção. Este calor de fricção promove a plastificação do material da junta, que ao mesmo tempo é misturado pelo pino consolidando, assim, a formação da junta. O objetivo do presente trabalho é avaliar a influência da utilização de diferentes perfis de ferramenta e diferentes velocidades de rotação sobre a soldagem e o comportamento mecânico de ligas de alumínio soldadas pelo processo de SPFMM. A caracterização metalúrgica foi feita através de microscopia ótica, lupa e eletrônica de varredura. A caracterização mecânica das juntas foi feita através de ensaios de cisalhamento, perfis de microdureza e monitoramento de torque e força durante o processo de soldagem. Ainda foram realizadas análises do fluxo de material durante o processo. Foi possível observar uma tendência de aumentar a resistência mecânica da junta com a utilização de velocidades de rotação mais elevadas em ambos os materiais. A utilização de ferramentas com diferentes perfis apresentou diferenças representativas, porém com muita dependência da combinação de velocidade de rotação, pino e ombro utilizados.Friction Stir Spot Welding is a process that occurs in solid state with high energy efficiency, low manufacture costs and environmentally friendly. These friction processes are an alternative to conventional processes like resistance spot welding, riveting and clinching. The absent of a fusion zone on these processes avoid defects like porosity, bubbles, recess, inclusions and undesired microstructures, that appears very often on weld metal and heat affected zones of fusion weld processes. The Friction Stir Spot Welding process (SPFMM- FSSW) consists in a rotating tool (pin and shoulder combined) that penetrates the overlap joint stirring the material and consolidating the joint. The contact of adjacent region of the tool generates the friction heating and, this heating, promotes the plasticization of the material that, at the same time, is stirred by the tool pin leaving a stir zone and a keyhole after process is finished. The aim of the present work is to evaluate the influence of tool profile and rotational speed on the mechanical and metallurgical behavior of friction stir spot welded AA6181-T4 aluminum alloy. The metallurgical characterization was performed through optical microscopy, stereoscope and scanning electron microscopy. The mechanical testing was made trough shear test, microhardness profile and torque/forces monitoring during the process. It was possible to observe a tendency of increasing in mechanical strength of the joint with applying higher rotational speed values. The utilization of different tool profiles presented significant differences, but, with much reliance of the rotational speed, pin and shoulder combination

Evaluaciòn ambientaldel terminal pesquero de santa rosa, provincia de Santa Elena

The Port of Santa Rosa belongs to Canton Salinas (village), province of Santa Elena, located between two ends, the first at the zone Petrópolis level and the second at the Primero de Enero neighborhood level. It is a community dedicated to the artisan fishing activity during most of the time, where the activity of the tourism has also been developed during the months of winter which is the sunny and beach seasonIt was possible to be known about the misstatement cause of our personal analysis of the compiled information and conversations that historically have been showing up in the port of Santa Rosa mainly salubrity, road planning and marine planning. In salubrity due all the activities of dispossession, cleaning and commercialization of the product is made mainly in the zone of the well-known beach “La Roca”. In road planning, cause all the activities of commercialization require of the motorized transport, plus the lack of infrastructure has got a mess of traffic in the rush hours. Finally, the marine planning does not exist The boats berth in the area in a random way which means a chaos between boats arriving and those that are bringing the broadside to bear and those that are in maintenance