There is a strong trend in the photovoltaic inverter technology to use transformerless topologies in order to acquire higher efficiencies combining with very low ground leakage current. In this ...paper, a new topology, based on the H-bridge with a new ac bypass circuit consisting of a diode rectifier and a switch with clamping to the dc midpoint, is proposed. The topology is simulated and experimentally validated, and a comparison with other existing topologies is performed. High conversion efficiency and low leakage current are demonstrated.
Este artículo analiza Semillas de cambio (2009) y El retorno de un lago (2014) de la artista brasileña Maria Thereza Alves desde la perspectiva del posthumanismo propuesta por Rosi Braidotti (2019). ...Se postula la pertinencia de entender ambas obras de Alves como formas de memoria a partir del concepto de testimonio no humano, una propuesta amparada en una noción de estética según la cual ella es entendida como un régimen de lo sensible orientado a aumentar nuestras capacidades perceptivas. Dicho marco da la pauta para entender cómo las obras estudiadas trabajan con el agua en tanto un archivo cuyo rastro, si se emplean las herramientas adecuadas, permite enunciar desde el lenguaje del arte las huellas de las empresas colonizadoras y cómo éstas continúan operando en la actualidad.
Background Information
Autophagy is a conserved process that functions as a cytoprotective mechanism; it may function as a cell death process called programmed cell death type II. There is ...considerable evidence for the presence of autophagic cell death during oocyte elimination in prepubertal rats. However, the mechanisms involved in this process have not been deciphered.
Results
Our observations revealed autophagic cell death in oocytes with increased labeling of the autophagic proteins Beclin 1, light chain 3 A (LC3 A), and lysosomal‐associated membrane protein 1 (Lamp1). Furthermore, mTOR and phosphorylated (p)‐mTOR (S2448) proteins were significantly decreased in oocytes with increased levels of autophagic proteins, indicating autophagic activation. Moreover, phosphorylated protein kinase B (p‐AKT) was not expressed by oocytes, but mitogen‐activated protein kinase/extracellular signalregulated kinase (MAPK/ERK) signaling was observed. Additionally, selective and elevated mitochondrial degradation was identified in altered oocytes.
Conclusions
All these results suggest that mTOR downregulation, which promotes autophagy, could be mediated by low energy levels and sustained starvation involving the phosphoinositide 3‐kinase (PI3K)/AKT/mTOR and MAPK/ERK pathways.
Significance
In this work, we analyzed the manner in which autophagy is carried out in oocytes undergoing autophagic cell death by studying the behavior of proteins involved in different steps of the autophagic pathway.
Autophagy in oocytes from atretic follicles is influenced by nutrients limitation and energy lowering. TSC1‐TSC2 signaling pathway is influenced by pAkt reduction. TSC2 protein serves as an inhibitor of mammalian target of rapamycin (mTOR) signaling inducing low p‐Ulk1 (S757) to stimulate autophagy. Simultaneously, low energy levels induce AMPK to phosphorylate p‐Ulk1 (S555) to promote autophagy, by increasing Beclin 1, LC3 A, and Lamp1 proteins, and lowering p62 protein levels.
In the compromise model of continuous opinions proposed by Deffuant et al., the states of two agents in a network can start to converge if they are neighbors and if their opinions are sufficiently ...close to each other, below a given threshold of tolerance
ϵ
. In directed networks, if agent
i
is a neighbor of agent
j
,
j
need not be a neighbor of
i
. In Watts–Strogatz networks we performed simulations to find the averaged number of final opinions
〈
F
〉
and their distribution as a function of
ϵ
and of the network structural disorder. In directed networks
〈
F
〉
exhibits a rich structure, being larger than in undirected networks for higher values of
ϵ
, and smaller for lower values of
ϵ
.
Human tuberculosis (TB) caused by members of the
complex (MTBC) is the main cause of death among infectious diseases worldwide. Pulmonary TB (PTB) is the most common clinical phenotype of the ...disease, but some patients develop an extrapulmonary (EPTB) phenotype in which any organ or tissue can be affected. MTBC species include nine phylogenetic lineages, with some appearing globally and others being geographically restricted. EPTB can or not have pulmonary involvement, challenging its diagnosis when lungs are not implicated, thus causing an inadequate treatment. Finding evidence of a specific
genetic background associated with EPTB is epidemiologically relevant due to the virulent and multidrug-resistant strains isolated from such cases. Until now, the studies conducted to establish associations between
lineages and PTB/EPTB phenotypes have shown inconsistent results, which are attributed to the strain predominance from specific
lineages/sublineages in the samples analyzed and the use of low-resolution phylogenetic tools that have impaired sublineage discrimination abilities. The present work elucidates the relationships between the MTBC strain lineages/sublineages and the clinical phenotypes of the disease as well as the antibiotic resistance of the strains.
To avoid biases, we retrieved the raw genomic reads (RGRs) of all (
= 245) the
strains worldwide causing EPTB available in databases and an equally representative sample of the RGRs (
= 245) of PTB strains. A multiple alignment was constructed, and a robust maximum likelihood phylogeny based on single-nucleotide polymorphisms was generated, allowing effective strain lineage/sublineage assignment.
A significant Odds Ratio (OR range: 1.8-8.1) association was found between EPTB and the 1.1.1, 1.2.1, 4.1.2.1 and ancestral Beijing sublineages. Additionally, a significant association between PTB with 4.3.1, 4.3.3, and 4.5 and Asian African 2 and Europe/Russia B0/W148 modern Beijing sublineages was found. We also observed a significant association of Lineage 3 strains with multidrug resistance (OR 3.8; 95% CI 1.1-13.6), as well as between modern Beijing sublineages and antibiotic resistance (OR 4.3; 3.8-8.6). In this work, it was found that intralineage diversity can drive differences in the immune response that triggers the PTB/EPTB phenotype.
We consider an elastic helical medium whose tensor stiffness twirls uniformly along the helix axis. We are interested in analyzing the band structure when the whole material is externally forced to ...rotate around the helix axis to a fixed constant frequency. Departing from a general dynamic description of the elastic phenomena, we establish a set of equations for the displacement vector and the stress tensor. These equations allow us to calculate the band structure parametrized by the externally imposed rotating frequency. We find that the band structure strongly depends on the rotation frequency, and we show that backward and forward modes propagate differently, particularly for the longitudinal and right-polarized modes.
We have incorporated the latest release of the Padova models into the evolutionary synthesis code Starburst99. The Padova tracks were extended to include the full asymptotic giant branch (AGB) ...evolution until the final thermal pulse over the mass range 0.9-5 M sub( ). With this addition, Starburst99 accounts for all stellar phases that contribute to the integrated light of a stellar population with arbitrary age from the extreme-ultraviolet to the near-infrared. AGB stars are important for ages between 0.1 and 2 Gyr, with their contribution increasing at longer wavelengths. We investigate similarities and differences between the model predictions by the Geneva and the Padova tracks. The differences are particularly pronounced at ages >1 Gyr, when incompleteness sets in for the Geneva models. We also perform detailed comparisons with the predictions of other major synthesis codes and find excellent agreement. Our synthesized optical colors are compared to observations of old, intermediate-age, and young populations. Excellent agreement is found for the old globular cluster system of NGC 5128 and for old and intermediate-age clusters in NGC 4038/4039. In contrast, the models fail for red supergiant-dominated populations with subsolar abundances. This failure can be traced back to incorrect red supergiant parameters in the stellar evolutionary tracks. Our models and the synthesis code are publicly available as version 5.0 of Starburst99 at http://www.stsci.edu/science/starburst99.
This study discusses the impact of the vertical component of earthquake ground motion in the performance level of steel building subjected to earthquake excitations. Analyses are carried out for the ...strong column-weak beam philosophy because the structural performance is focused on these elements. A realistic steel frame is also considered to investigate the impact of including the seismic vertical component in the non-linear response of the building. The main findings of this study are: (1) When an analysis is performed by considering the horizontal and vertical components of ground motion acting simultaneously (near the causative fault), larger plastic rotations in the beams are obtained as compared to those resulting by considering only the horizontal component. (2) Due to the previous finding, if a codified criterion to inspect the steel beams performance in terms of the plastic rotation is considered, the beam performance could lie within a different acceptation criterion (i.e., from immediate occupancy to collapse prevention) if the vertical component is included in the analysis.
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