Analysis of asymmetric T-stub components: experimental and numerical approach

Este artículo presenta el análisis mediante técnicas numéricas y experimentales de componentes T-equivalente asimétricas, refiriéndose ésta al posicionamiento de los pernos respecto al alma del perfil. El objetivo principal de realizar este análisis es el de evaluar la influencia de dicha asimetría en la rigidez y sobre todo en la resistencia final, y compararlas a las de componentes simétricas. Se definen dos modelos numéricos para analizar el comportamiento: uno matricial de barras rígidas y otro con elementos finitos sólidos. Los resultados obtenidos con ambos modelos se comparan con ensayos experimentales, tanto para para una componente simétrica como una asimétrica, obteniéndose un error menor del 10 % para el cálculo de la rigidez e inferior al 20% para la resistencia final. Se comprueba que, como cabía esperar, la asimetría repercute en una redistribución de la carga en los pernos, produciéndose un fallo prematuro del conjunto con respecto a la configuración simétrica. Por tanto, puede deducirse que los análisis numéricos realizados son capaces de cuantificar dicha redistribución.The analysis of asymmetric T-stub components by the position of bolts respect to the web, has been carried out using numerical and experimental approaches. The main objective of this analysis is to evaluate the influence of such asymmetry on the stiffness and strength. A matrix frame model with beam-column elements and rigid connections has been developed as well as with solid elements. Results obtained with these numerical models have been compared with those obtained from experimental tests carried out, for both symmetrical and asymmetrical components, obtaining errors below 10% for stiffness and lower than 20% for the final strength. It was found, as expected, that the asymmetry leads to a redistribution of the load on the bolts, causing premature failure of the assembly. Therefore the numerical analysis performed is capable of quantifying such redistribution.Peer Reviewe

A monolithic continuous-flow microanalyzer with amperometric detection based on the green tape technology

The development of micro total analysis systems (muTAS) has become a growing research field. Devices that include not only the fluidics and the detection system but also the associated electronics are reported scarcely in the literature because of the complexity and the cost involved for their monolithic integration. Frequently, dedicated devices aimed at solving specific analytical problems are needed. In these cases, low-volume production processes are a better alternative to mass production technologies such as silicon and glass. In this work, the design, fabrication, and evaluation of a continuous-flow amperometric microanalyzer based on the green tape technology is presented. The device includes the microfluidics, a complete amperometric detection system, and the associated electronics. The operational lifetime of the working electrode constitutes a major weak point in electrochemical detection systems, especially when it is integrated in monolithic analytical devices. To increase the overall system reliability and its versatility, it was integrated following an exchangeable configuration. Using this approach, working electrodes can be readily exchanged, according to the analyte to be determined or when their surfaces become passivated or poisoned. Furthermore, the electronics of the system allow applying different voltamperometric techniques and provide four operational working ranges (125, 12.5, 1.25, and 0.375 muA) to do precise determinations at different levels of current intensity.The authors would like to thank the Spanish MEC for its financial support through: Consolider-Ingenio 2010 (CSD2006-00012), TEC2006-13907-C04-04/MIC and CIT- 310200-2007-29

Cardio Balance

Seminario Desarrollo de Emprendedores. 2015. Carrera Medicina.. Docente Dra. Pilarte y Dr. Aguilar.Cardio Balance esta comprometido en desarrollar un servicio que satisfaga las necesidades básicas de los pacientes cardiópatas, a nivel de la prevención primaria y secundaria, sin objetivo lucrativo, solamente que sea auto-sostenible

Promover os direitos das crianças - apostar na construção de melhores políticas públicas para a criança

Comunicação apresentada no 3º Encontro de Conhecimento e Cooperação, INA, Lisboa, 17 de setembro de 201

Pandrug-Resistant Acinetobacter baumannii Causing Nosocomial Infections in a University Hospital, Taiwan

The rapid emergence (from 0% before 1998 to 6.5% in 2000) of pandrug-resistant Acinetobacter baumannii (PDRAB) was noted in a university hospital in Taiwan. To understand the epidemiology of these isolates, we studied 203 PDRAB isolates, taken from January 1999 to April 2000: 199 from 73 hospitalized patients treated at different clinical settings in the hospital and 4 from environmental sites in an intensive-care unit. Pulsed-field gel electrophoresis analysis and random amplified polymorphic DNA (RAPD) generated by arbitrarily primed polymerase chain reaction of these 203 isolates showed 10 closely related genotypes (10 clones). One (clone 5), belonging to pulsotype E and RAPD pattern 5, predominated (64 isolates, mostly from patients in intensive care). Increasing use of carbapenems and ciprofloxacin (selective pressure) as well as clonal dissemination might have contributed to the wide spread of PDRAB in this hospital

SCUBA divers as oceanographic samplers: The potential of dive computers to augment aquatic temperature monitoring

Monitoring temperature of aquatic waters is of great importance, with modelled, satellite and in-situ data providing invaluable insights into long-term environmental change. However, there is often a lack of depth-resolved temperature measurements. Recreational dive computers routinely record temperature and depth, so could provide an alternate and highly novel source of oceanographic information to fill this data gap. In this study, a citizen science approach was used to obtain over 7,000 scuba diver temperature profiles. The accuracy, offset and lag of temperature records was assessed by comparing dive computers with scientific conductivity-temperature-depth instruments and existing surface temperature data. Our results show that, with processing, dive computers can provide a useful and novel tool with which to augment existing monitoring systems all over the globe, but especially in under-sampled or highly changeable coastal environments

Pesquisa sobre eficiência energética: Um desenho metodológico de estudo teórico e prático para prédios e indústrias da Amazônia / Energy efficiency research: A methodological design of theoretical and practical study for buildings and industries in the Amazon

No presente trabalho os autores apresentam uma proposta de desenho metodológico teórica e prática para desenvolver pesquisa de análise da eficiência energética, aplicável a prédios e indústrias existentes na zona tropical da Amazônia, visando economia de energia e sustentabilidade ao meio ambiente. O desenho, que hierarquiza o conhecimento dos parâmetros da eficiência energética, pode ser utilizado como ferramenta de avaliações energéticas e como material complementar no ensino. Partindo de um estudo de caso, o trabalho se aprofunda na teoria-científica, a partir da utilização dos avanços atuais das técnicas de modelagem e simulação, com o auxílio dos meios informáticos existentes nas universidades e centros de pesquisas. Isto permitiu a otimização na obtenção de resultados, a divulgação e capacitação dos gestores, acarretando diminuição dos consumos energéticos de prédios e indústrias com menor impacto ao meio ambiente amazônico

Efficient unfolding pattern recognition in single molecule force spectroscopy data

BackgroundSingle-molecule force spectroscopy (SMFS) is a technique that measures the force necessary to unfold a protein. SMFS experiments generate Force-Distance (F-D) curves. A statistical analysis of a set of F-D curves reveals different unfolding pathways. Information on protein structure, conformation, functional states, and inter- and intra-molecular interactions can be derived.ResultsIn the present work, we propose a pattern recognition algorithm and apply our algorithm to datasets from SMFS experiments on the membrane protein bacterioRhodopsin (bR). We discuss the unfolding pathways found in bR, which are characterised by main peaks and side peaks. A main peak is the result of the pairwise unfolding of the transmembrane helices. In contrast, a side peak is an unfolding event in the alpha-helix or other secondary structural element. The algorithm is capable of detecting side peaks along with main peaks.Therefore, we can detect the individual unfolding pathway as the sequence of events labeled with their occurrences and co-occurrences special to bR\u27s unfolding pathway. We find that side peaks do not co-occur with one another in curves as frequently as main peaks do, which may imply a synergistic effect occurring between helices. While main peaks co-occur as pairs in at least 50% of curves, the side peaks co-occur with one another in less than 10% of curves. Moreover, the algorithm runtime scales well as the dataset size increases.ConclusionsOur algorithm satisfies the requirements of an automated methodology that combines high accuracy with efficiency in analyzing SMFS datasets. The algorithm tackles the force spectroscopy analysis bottleneck leading to more consistent and reproducible results

The role of climate, marine influence and sedimentation rates in late-Holocene estuarine evolution (SW Portugal)

Estuaries are sensitive to changes in global to regional sea level, to climate-driven variation in rainfall and to fluvial discharge. In this study, we use source and environmentally sensitive proxies together with radiocarbon dating to examine a 7-m-thick sedimentary record from the Sado estuary accumulated throughout the last 3.6 kyr. The lithofacies, geochemistry and diatom assemblages in the sediments accumulated between 3570 and 3240 cal. BP indicate a mixture between terrestrial and marine sources. The relative contribution of each source varied through time as sedimentation progressed in a low intertidal to high subtidal and low-energy accreting tidal flat. The sedimentation proceeded under a general pattern of drier and higher aridity conditions, punctuated by century-long changes of the rainfall regime that mirror an increase in storminess that affected SW Portugal and Europe. The sediment sequence contains evidence of two periods characterized by downstream displacement of the estuarine/freshwater transitional boundary, dated to 3570-3400 cal. BP and 3300-3240 cal. BP. These are intercalated by one episode where marine influence shifted upstream. All sedimentation episodes developed under high terrestrial sediment delivery to this transitional region, leading to exceptionally high sedimentation rates, independently of the relative expression of terrestrial/marine influences in sediment facies. Our data show that these disturbances are mainly climate-driven and related to variations in rainfall and only secondarily with regional sea-level oscillations. From 3240 cal. BP onwards, an abrupt change in sediment facies is noted, in which the silting estuarine bottom reaches mean sea level and continued accreting until present under prevailing freshwater conditions, the tidal flat changing to an alluvial plain. The environmental modification is accompanied by a pronounced change in sedimentation rate that decreased by two orders of magnitude, reflecting the loss of accommodation space rather than the influence of climate or regional sea-level drivers.FCT by Spanish Ministry of Science and Innovation [SFRH/BD/110270/2015, HAR2014-51830-P, HAR2011-29907-C03-00]FCTPortuguese Foundation for Science and Technology [PTDC/HISARQ/121592/2010]Instituto Dom Luiz-IDL [UID/GEO/50019/2013]info:eu-repo/semantics/publishedVersio

Health workers' perspectives on asthma care coordination between primary and specialised healthcare in the COVID-19 pandemic: a protocol for a qualitative study in Ecuador and Brazil.

INTRODUCTION: Asthma is a common long-term disorder and strategies to improve asthma control are still a challenge. Integrated delivery of health systems is critical for effective asthma care: there is limited information on experiences of care coordination for asthma from Latin America, especially on perspectives of health personnel and in the context of the COVID-19 pandemic. METHODS AND ANALYSIS: This protocol details a qualitative approach to analyse health workers' perspectives of healthcare coordination for asthma control during COVID-19 pandemic in Ecuador and Brazil, at primary and specialised levels, through in-depth semistructured interviews using a video communications platform. The analysis will identify knowledge and perspectives based on coordination of clinical information, clinical management and administrative coordination. Theoretical sampling will be used to obtain approximately equal numbers of women and men within each level of healthcare; data saturation will be used to determine sample size. Transcripts will be analysed using content-coding procedures to mark quotations related to major topics and subthemes included in the interview guide, and narrative analysis will be based on a theoretical framework for healthcare coordination to identify new themes and subthemes. ETHICS AND DISSEMINATION: Ethical approval was obtained from the ethics committees of Hospital General Docente Calderón, Quito, Ecuador; and Universidade Federal da Bahia, Salvador, Brazil. The findings of this study will be disseminated through peer-reviewed articles, conference presentations and condensed summaries for key stakeholders and partners