Heat treatment as a route to tailor the yield-damping properties in A356 alloys

A356 is a common industrial alloy due to its relatively good mechanical properties, reduced weight and capability be casted into complex structures. However, in order to display good static mechanical properties (e.g.elevated yield strength) it must be heat treated (usually T6), therefore, compromising its dynamic properties (e.g. damping ratio). This study analyses the role of such heat treatments in the overall microstructure of A356 poured in ceramic block, associating the morphology transformations with the internal mechanisms that enhance yield strength and reduce damping. It is suggested that these variables display an inverse proportionality and a linear model is determined for the design of alloys with tailored yield/damping by the use of different artificial ageing times.Supported by the project iRAIL Innovation in Railway Systems and Technologies Doctoral Programme funds and by national funds through FCT - Portuguese Foundation for Science and Technology and was developed on the aim of the Doctoral grant PD/ BD/114096/2015

Simple and complex modelling of timber-framed masonry walls in Pombalino buildings

Timber-framed masonry has been developed as an effective lateral-load resisting system in regions of high seismicity such as Southern Europe. A salient feature of the ‘last generation’ of timber-framed (TF) buildings is the presence of diagonal members that may consist of two diagonal braces. The present study focusses on alternative modelling procedures, ranging from simple to rather complex, for this interesting type of traditional structure. All models are applied to study the behaviour of full-scale specimens of diagonally-braced TF panels. The complex model is based on plasticity with contact surfaces for the connection between timber diagonals and masonry infills. A parametric analysis using this model shows that masonry infills affect only slightly the lateral force carried by this TF panel configuration. Furthermore, two simple modelling techniques are put forward for application in the analysis of large, realistic structures incorporating TF walls. The first one is directly connected to the complex modelling and is based on substructuring. A nine-step procedure is developed and is found to properly reproduce the response of the test specimens. The second simple model is a phenomenological one, developed on the basis of observed behaviour during tests and is a complete hysteretic model; however, for comparison purposes, all models are evaluated here with respect to the prediction of the envelope (pushover) curve for the walls tested under lateral loads

Transitions Between Preexposure Prophylaxis Eligibility States and HIV Infection in the Lisbon Cohort of HIV-Negative Men Who Have Sex With Men: A Multistate Model Analysis

We aimed to describe transitions between preexposure prophylaxis (PrEP) eligibility and human immunodeficiency virus (HIV) infection among HIV-negative men who have sex with men (MSM). We used data from 1,885 MSM, who had not used PrEP, enrolled in the Lisbon Cohort of MSM, with at least 2 consecutive measurements of PrEP eligibility from 2014–2020. A time-homogeneous Markov multistate model was applied to describe the transitions between states of PrEP eligibility—eligible and ineligible—and from these to HIV infection (HIV). The intensities of the transitions were closer for ineligible-to-eligible and eligible-to-ineligible transitions (intensity ratio, 1.107, 95% confidence interval (CI): 1.080, 1.176), while the intensity of the eligible-to-HIV transition was higher than that for ineligible-to–HIV transition (intensity ratio, 9.558, 95% CI: 0.738, 65.048). The probabilities of transitions increased with time; for 90 days, the probabilities were similar for the ineligible-to-eligible and eligible-to-ineligible transitions (0.285 (95% CI: 0.252, 0.319) vs. 0.258 (95% CI: 0.228, 0.287)), while the eligible-to-HIV transition was more likely than ineligible-to-HIV (0.004 (95% CI: 0.003, 0.007) vs. 0.001 (95% CI: 0.001, 0.008)) but tended to become closer with time. Being classified as ineligible was a short-term indicator of a lower probability of acquiring HIV. Once an individual moved to eligible, he was at a higher risk of seroconversion, demanding a timely delivery of PrEP.This work was supported by national funds of Fundação para a Ciência e Tecnologia (FCT), under the scope of the project UIDB/04750/2020—Research Unit of Epidemiology–Institute of Public Health of the University of Porto (EPIUnit). P.M. was the recipient of doctoral grant SFRH/BD/112867/2015, co-funded by the FCT and the Programa Operacional Capital Humano/Fundo Social Europeu. C.M. was supported by Portuguese funds through FCT within the Project UID/MAT/00013/2013

Isolamento de Toxoplasma gondii a partir de cérebro e músculo de gatos serologicamente positivos utilizando culturas celulares

O isolamento de Toxoplasma gondii é imprescindível quer para efeitos de diagnóstico definitivo da infecção, quer para estudos visando a genotipagem de estirpes circulantes, tanto nos animais como no ser humano. O bioensaio é presentemente considerado o método de eleição para isolamento de T. gondii de amostras biológicas, no entanto, para além de eticamente questionável, a inoculação em ratinho é dispendiosa e laboriosa. O ensaio in vitro utilizando culturas celulares é frequentemente mencionado como alternativa, contudo o investimento nesta área tem sido diminuto, sendo raros os trabalhos que referem o recurso a este método para isolamento de T. gondii a partir de tecidos animais. Este estudo teve como objectivo testar diferentes métodos de isolamento de T. gondii em culturas de células. Para a preparação dos inóculos, colhemos amostras de tecido cerebral e muscular (coração e membros) de 16 gatos serologicamente positivos, durante a necrópsia. O tecido cerebral foi homogeneizado com agulha e seringa em meio de cultura e o tecido muscular digerido numa solução de ácido clorídrico e pepsina. A inoculação dos homogeneizados de cérebro e músculo em culturas de células Vero resultou, respectivamente, numa taxa de isolamento de 37,5% (6/16) e 62,5% (10/16). A visualização microscópica de taquizoítos nas culturas celulares foi possível 5-14 dias pós-inoculação, utilizando homogeneizados de cérebro e 7-32 dias pós-inoculação, utilizando homogeneizados de tecido muscular. Todos os isolados foram confirmados por n-PCR visando a região ITS1 do rDNA de T. gondii

The SARS-CoV-2 Infection Among Students in the University of Porto: A Cross-Sectional Study

Objective: We aimed to quantify SARS-CoV-2 specific antibodies’ seroprevalence among university students in Porto. Methods: A rapid point of care testing for SARS-CoV-2 specific immunoglobulin (Ig) M and IgG antibodies was performed, and a questionnaire was applied to 6512 voluntary students from September to December 2020. We computed the apparent IgM, IgG, and IgM or IgG prevalence, and the true prevalence and 95% credible intervals (95% CI) using Bayesian inference. Results: We found an apparent prevalence (IgM or IgG) of 9.7%, the true prevalence being 7.9% (95% CI 4.9–11.1). Prevalence was significantly higher among males (10.9% vs. 9.2%), international students (18.1% vs. 10.4% local vs. 8.8% nationally displaced), and increased with age. Those with a known risk contact, that experienced quarantine, had symptoms, or a previous negative molecular test had a higher seroprevalence. Of the 91 (1.4%) students who reported a molecular diagnosis, 86.8% were reactive for IgM or IgG. Conclusion: Based on immunological evidence infection was 5.6-fold the reported molecular diagnosis. The higher seroprevalence among male, older, and international students emphasizes the importance of identifying particular groups. Copyright © 2022 Meireles, Costa, Novais, Miranda, Lopes, Severo and Barros.This study was funded by University of Porto and supported by national funds of Fundação para a Ciência e Tecnologia, under the scope of the projects UIDB/04750/2020—Research Unit of Epidemiology–Institute of Public Health of the University of Porto (EPIUnit) and LA/P/0064/2020–Laboratory for Integrative and Translational Research in Population Health (ITR). JPC was the recipient of PhD grant (DFA/BD/8562/2020) co-funded by the national funds of Fundação para a Ciência e Tecnologia and the Fundo Social Europeu

Principles of condom provision programs in prisons from the standpoint of European prison health experts: a qualitative study

Background Condom provision is one of the most effective harm reduction interventions to control sexually transmitted infections (STIs) including HIV/AIDS and viral hepatitis in prisons. Yet, very few countries around the world provide prisoners with condoms. The present study aimed to elucidate principles of effective prison-based condom programs from the perspective of European public health and prison health experts. Methods As a part of the “Joint Action on HIV and Co-infection Prevention and Harm Reduction (HA-REACT)” twenty-one experts from the field of prison health from eight European countries were invited to discuss the principles of condom provision programs in prisons within two focus groups. The audio records were transcribed verbatim, coded, categorized, and analyzed using thematic analysis method. Results Six components emerged from the analysis as essential for successful condom programs in prisons: (1) highlighting the necessity of condom provision in prisons, (2) engagement of internal and external beneficiaries in all stages of designing and implementing the program, (3) conducting a pilot phase, (4) condom program in a comprehensive package of harm reduction interventions, (5) vending machine as the best method of condom distribution in prisons and (6) assuring the sustainability and quality of the intervention. Conclusion Results of the present study can help prison health policy makers to design and conduct acceptable, accessible and high-quality prison-based condom provision programs, and consequently to mitigate the burden of STIs in prisons. Having access to high-quality healthcare services including condom provision programs is not only the right of prisoners to health, but also is a move towards achieving the sustainable development goal 3 of “leaving no one behind.”Open Access funding enabled and organized by Projekt DEAL

Retaining Expression on De-identified Faces

© Springer International Publishing AG 2017The extensive use of video surveillance along with advances in face recognition has ignited concerns about the privacy of the people identifiable in the recorded documents. A face de-identification algorithm, named k-Same, has been proposed by prior research and guarantees to thwart face recognition software. However, like many previous attempts in face de-identification, kSame fails to preserve the utility such as gender and expression of the original data. To overcome this, a new algorithm is proposed here to preserve data utility as well as protect privacy. In terms of utility preservation, this new algorithm is capable of preserving not only the category of the facial expression (e.g., happy or sad) but also the intensity of the expression. This new algorithm for face de-identification possesses a great potential especially with real-world images and videos as each facial expression in real life is a continuous motion consisting of images of the same expression with various degrees of intensity.Peer reviewe

Reviewing Treatment Options for Advanced Renal Cell Carcinoma: Is There Still a Place for Tyrosine Kinase Inhibitor (TKI) Monotherapy?

Renal cell carcinoma (RCC) comprises a highly heterogeneous group of kidney tumours built upon distinct genetic- and epigenetic-driven mechanisms and molecular pathways. Therefore, responsiveness to treatment is considerably variable across patients, adding an extra layer of complexity to the already challenging therapeutic decision process. The last decade brought an unprecedented shift in the medical approach to advanced or metastatic RCC; in fact, immunotherapy-based combinations have significantly transformed the therapeutic arsenal and clinical outcomes of these patients. These strategies were quickly adopted by international guidelines committees as the new standards of care. However, this enhanced efficacy comes at the expense of tolerability, with a predictable negative impact on patients' quality of life. Moreover, subgroup and post hoc analyses of the major clinical trials have shown that not all patients benefit equally from these innovative approaches. In this context, a group of experts on kidney cancer met and discussed the state of the art in the field, with a special emphasis on the appropriateness of using monotherapy with an anti-angiogenesis tyrosine kinase inhibitor (TKI) to treat specific subgroups of patients with RCC. This article reviews the main topics that were considered to be pertinent for that discussion and establishes the profile of patients for whom TKI monotherapy remains a sensible frontline option by avoiding overtreatment and an unnecessary exposure to treatment-related toxicity.info:eu-repo/semantics/publishedVersio