Thin corrugated-edge shells inspired by Nervi’s dome: Numerical insight about their mechanical behaviour

During the last decades, the constant evolution of the construction systems has led to the possibility of carrying out increasingly complex architectural project. Among the wide range of construction systems, thin concrete shells with corrugated-edge stand out for their relevance. In this paper, the mechanical behaviour of thin concrete corrugated-edge shell inspired by Nervi’s Flaminio dome has been analysed in detail, considering different load configurations (self-weight, uniform normal pressure and antisymmetric vertical load) and constraints (pure membrane vs. displacements restrained boundary conditions). Non-linear static analysis has been performed to assess the vertical load-bearing capacity of the corrugatededge shell considering a Concrete Damaged Plasticity (CDP) constitutive model and linear and non-linear buckling analyses have been carried out to evaluate the effects of the corrugation on buckling behaviour. The results obtained from linear and non-linear analyses have been compared with those obtained for a concrete thin smooth-edge shell having the same geometric global characteristics. The comparison highlighted improvements provided by corrugated-edge in terms of structural behaviour

Comparación de modelos sísmicos para un edificio histórico en mampostería

En este proyecto se ha considerado como caso de estudio un edificio histórico de mampostería en Cerdeña, Italia, cuyo modelado, análisis estático y sísmico han sido desarrollados. En este estudio se han empleado dos programas informáticos con distintos enfoques de modelización con el propósito de comparar y discutir los resultados. Como primer simulador del comportamiento de la estructura en mampostería se ha elegido SismiCad12, que es una suite de Elementos Finitos (FEM, por sus siglas en inglés) que permite modelar y analizar la mayoría de los tipos de estructuras 3D y es adecuado para estructuras de mampostería. Por otro lado, se ha aplicado un método de modelado diferente e innovador denominado Frame Macro Elements (FME) con el software 3Muri, diseñado específicamente para evaluar el comportamiento lineal, no lineal y sísmico de las estructuras en mampostería.  Suponiendo la misma hipótesis para construir el modelo 3D de la estructura en cada código, los resultados de los análisis estáticos muestran una diferente repartición de las cargas verticales en la estructura, las que son más realísticas en el modelado FEM. Este diferente criterio de evaluación de las cargas verticales lleva un mecanismo de “piso suave”   In this project, a historic masonry building in Sardinia, Italy has been considered as a case study for the comparison of two approaches for modeling, static and seismic analysis. Two software with different modeling approaches were employed with the purpose of comparing and discussing the results. SismiCad12 was used to simulate the structural behavior of the historic masonry building. SismiCad12 uses the Finite Element Method (FEM) that allows to model and analyze most types of 3D structures, and it is suitable for masonry structures. On the other hand, a different and innovative modeling approach called Frame Macro Elements (FME) was also applied using the 3Muri software, specially designed for assessing the linear, nonlinear, and seismic behavior of masonry structures.  Assuming the same hypothesis to construct the 3D model of the structure in each code, the results of the static analysis show a different distribution of the vertical loads in the structure, which are more realistic in the FEM modeling. This different criterion of evaluation of the vertical loads carries a mechanism of "soft floor" in the pushover analysis in the FEM modeling, and therefore, a lower ultimate displacement corresponding to the collapse of the structure. On the other hand, in dynamic analyzes, FME modeling is more receptive to reality, involving a massive percentage of masses participating in the first vibration modes

Structural Identification from Operational Modal Analysis: The Case of Steel Structures

In the case of old existing structures where the cultural value is very high, structural health analyses and investigations would be better performed without damages or service interruptions. Thus, modal analysis aimed at identifying eigenfrequencies and eigenmodes represents a very effective strategy to identify structural characteristics. In this paper, an innovative strategy to identify structural parameters exploiting the modal information obtained from operational modal analysis is proposed. The importance of the structural modeling in the problem formulation is highlighted. In the case of a simply supported beam, it was possible to assess the beam steel elastic modulus, while in the case of a cantilever beam, some constraint characteristics have been evaluated as well. In the steel frame case, the focus was on the constraint conditions of the structure determining the flexural stiffness of the springs representing the column base constraints. The method performances are promising for applications in larger structures such as bridges and buildings

A sulfur-based transport pathway in Cu^+-ATPases

Cells regulate copper levels tightly to balance the biogenesis and integrity of copper centers in vital enzymes against toxic levels of copper. P_(IB)‐type Cu^+‐ATPases play a central role in copper homeostasis by catalyzing the selective translocation of Cu^+ across cellular membranes. Crystal structures of a copper‐free Cu^+‐ATPase are available, but the mechanism of Cu^+ recognition, binding, and translocation remains elusive. Through X‐ray absorption spectroscopy, ATPase activity assays, and charge transfer measurements on solid‐supported membranes using wild‐type and mutant forms of the Legionella pneumophila Cu^+‐ATPase (LpCopA), we identify a sulfur‐lined metal transport pathway. Structural analysis indicates that Cu^+ is bound at a high‐affinity transmembrane‐binding site in a trigonal‐planar coordination with the Cys residues of the conserved CPC motif of transmembrane segment 4 (C382 and C384) and the conserved Met residue of transmembrane segment 6 (M717 of the MXXXS motif). These residues are also essential for transport. Additionally, the studies indicate essential roles of other conserved intramembranous polar residues in facilitating copper binding to the high‐affinity site and subsequent release through the exit pathway

Phenotypic miRNA Screen Identifies miR-26b to Promote the Growth and Survival of Endothelial Cells

Endothelial cell (EC) proliferation is a crucial event in physiological and pathological angiogenesis. MicroRNAs (miRNAs) have emerged as important modulators of the angiogenic switch. Here we conducted high-content screening of a human miRNA mimic library to identify novel regulators of EC growth systematically. Several miRNAs were nominated that enhanced or inhibited EC growth. Of these, we focused on miR-26b, which is a conserved candidate and expressed in multiple human EC types. miR-26b overexpression enhanced EC proliferation, migration, and tube formation, while inhibition of miR-26b suppressed the proliferative and angiogenic capacity of ECs. A combinatory functional small interfering RNA (siRNA) screening of 48 predicted gene targets revealed that miR-26b enhanced EC growth and survival through inhibiting PTEN expression. Local administration of miR-26b mimics promoted the growth of new microvessels in the Matrigel plug model. In the mouse model of hindlimb ischemia, miR-26b was found to be downregulated in endothelium in the first week following ischemia, and local overexpression of miR-26b improved the survival of capillaries and muscle fibers in ischemic muscles. Our findings suggest that miR-26b enhances EC proliferation, survival, and angiogenesis. miR-26b is a potential target for developing novel pro-angiogenic therapeutics in ischemic disease. Keywords: high content screen, miRNA mimic library, miR-26b, endothelial cells, cell growt

Quantum Computing for High-Energy Physics: State of the Art and Challenges. Summary of the QC4HEP Working Group

Quantum computers offer an intriguing path for a paradigmatic change of computing in the natural sciences and beyond, with the potential for achieving a so-called quantum advantage, namely a significant (in some cases exponential) speed-up of numerical simulations. The rapid development of hardware devices with various realizations of qubits enables the execution of small scale but representative applications on quantum computers. In particular, the high-energy physics community plays a pivotal role in accessing the power of quantum computing, since the field is a driving source for challenging computational problems. This concerns, on the theoretical side, the exploration of models which are very hard or even impossible to address with classical techniques and, on the experimental side, the enormous data challenge of newly emerging experiments, such as the upgrade of the Large Hadron Collider. In this roadmap paper, led by CERN, DESY and IBM, we provide the status of high-energy physics quantum computations and give examples for theoretical and experimental target benchmark applications, which can be addressed in the near future. Having the IBM 100 x 100 challenge in mind, where possible, we also provide resource estimates for the examples given using error mitigated quantum computing

Dark Matter and Neutrino Masses from Global U(1)B−LU(1)_{B-L} Symmetry Breaking

We present a scenario where neutrino masses and Dark Matter are related due to a global $U(1)_{B-L}$ symmetry. Specifically we consider neutrino mass generation via the Zee--Babu two-loop mechanism, augmented by a scalar singlet whose VEV breaks the global $U(1)_{B-L}$ symmetry. In order to obtain a Dark Matter candidate we introduce two Standard Model singlet fermions. They form a Dirac particle and are stable because of a remnant $Z_2$ symmetry. Hence, in this model the stability of Dark Matter follows from the global $U(1)_{B-L}$ symmetry. We discuss the Dark Matter phenomenology of the model, and compare it to similar models based on gauged $U(1)_{B-L}$. We argue that in contrast to the gauged versions, the model based on the global symmetry does not suffer from severe constraints from $Z'$ searches.Comment: minor improvements, matches published versio

Superior Effectiveness of Zidovudine Compared With Tenofovir When Combined With Nevirapine-based Antiretroviral Therapy in a Large Nigerian Cohort

Background. Despite sparse efficacy data, tenofovir–emtricitabine or tenofovir–lamivudine plus nevirapine is used in many resource-constrained settings. Methods. This retrospective cohort study included patients initiating nevirapine-based antiretroviral therapy (ART) with either tenofovir–emtricitabine or lamivudine (tenofovir group) or zidovudine–lamivudine (zidovudine group). Clinical, virologic, and immunologic evaluations were performed at baseline and every 6 months. Virologic failure was defined as 2 consecutive human immunodeficiency virus (HIV)-RNA values >1000 copies/mL. Patients were included from ART initiation until time of failure, regimen switch, discontinuation, or last HIV-RNA measurement. Cox proportional hazards regression was used to model factors influencing time to failure. Bias due to dependent censoring was investigated via inverse probability weighted pooled logistic regression. Results. A total of 5547 patients were evaluated; 1484 (26.8%) were in the tenofovir group and 4063 (73.2%) were in the zidovudine group. In the adjusted model, tenofovir regimen (hazard ratio [HR], 1.47; 95% confidence interval [CI], 1.21–1.79) and higher baseline log10 HIV-RNA (HR, 1.15; 95% CI, 1.03–1.28) were associated with virologic failure. Higher baseline log10 CD4+ cell count (HR, 0.50; 95% CI, .40–.63) and increasing age (HR, 0.98; 95% CI, .97–.99) decreased the risk of virologic failure. Inverse probability weighting results were consistent with the primary analysis. Conclusions. Compared with zidovudine–lamivudine, the use of tenofovir–lamivudine or emtricitabine in combination with nevirapine was a strong predictor of virologic failure in our cohort, which was not explained by other risk factors or criteria for regimen selection

What do they do after class? extra curriculum activities of medical students of ribeirão preto-University of São Paulo

Em 1999, o Programa Especial de Treinamento da Faculdade de Medicina de Ribeirão Preto, da Universidade de São Paulo realizou um estudo com 326 alunos, do primeiro ao quarto ano, com o objetivo de identificar e descrever as atividades extracurriculares desses alunos. Em 2002, o estudo foi repetido, utilizando-se o mesmo instrumento, aplicado em 360 alunos. Trata-se, portanto, de estudo transversal, cujas variáveis estudadas são: idade, sexo, ano do curso, atividades extracurriculares ligadas à FMRP-USP, motivo da pratica de tais atividades, horas despendidas com elas, grau de satisfação e motivo de satisfação e insatisfação. Do total de entrevistados, 64% são homens e 36% são mulheres. A média da idade é 20,7 anos e apenas 8% (29) não estavam engajados em nenhuma atividade extracurricular na época da entrevista. Das atividades mais freqüentadas estão as ligas (73%), os treinos esportivos (53%), os estágios em laboratório de iniciação científica (31,5%) e os plantões voluntários (31%). Das atividades não relacionadas à Faculdade, 36% referiram-se ao estudo de uma língua estrangeira e 24,5%, à música ou ao teatro. A maioria gasta, pelo menos, cinco horas semanais com essas atividades. Maior número de atividades foi encontrado, associado ao maior o tempo de permanência do aluno no curso médico (p=0,002), embora a carga horária da grade curricular também aumente com o passar do tempo. Embora não tenham sido encontradas grandes diferenças, ao compararmos os alunos entrevistados em 1999 e 2002, houve aumento significativo de participação em ligas, já que novas foram criadas no período.In 1999 the Special Training Programme of the Medical School of Ribeirão Preto conducted a study with 326 undergraduate students from the first to the fourth grade aiming to identify and describe their extra curriculum activities. In 2002 the study was repeated administering the same questionnaire among 360 students. It is, therefore, a cross-seccional study in which the variables are age, sex, grade of course, extra curriculum activities linked to the school, reasons for these activities, weekly hours spent with them, satisfaction levels and reasons for satisfaction or dissatisfaction. From the total of interviewees 64% are male and 36% female, the median age found was 20,7 years old and only 8% (29) of students are not enrolled in any extra curriculum activity at the time of the interview. Belonging to a study group named “leagues” (73%), practicing some sport (53%), developing research (31,5%) or voluntary medical night calls (31%) are amongst the most popular actitivies. Among the activities not linked to the school most students reported to study a foreign language (36%), music or theatre (24,5%). Most of them reported spending at least five hours per week with some of these activivies. Greater number of activities were found associated to higher grade at medical school (p=0,002) despite the increase of time in class. Although there were not found great differences among the students interviewed in 1999 and 2002, there was a significant increase of participation in “leagues” since new of them were created during this time