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241.
Felipe?A.?C.?VianaEmail author Raphael?T.?Haftka Layne?T.?Watson 《Structural and Multidisciplinary Optimization》2012,45(4):615-618
We demonstrate the use of multiple surrogates and kriging believer for parallelizing surrogate-based contour estimation. For
the demonstration example, we reduce wall clock time with minimal penalty in number of simulations. 相似文献
242.
Irina V. Milanova Felipe Correa-da-Silva Andries Kalsbeek Chun-Xia Yi 《International journal of molecular sciences》2021,22(6)
The prevalence of obesity has increased rapidly in recent years and has put a huge burden on healthcare worldwide. Obesity is associated with an increased risk for many comorbidities, such as cardiovascular diseases, type 2 diabetes and hypertension. The hypothalamus is a key brain region involved in the regulation of food intake and energy expenditure. Research on experimental animals has shown neuronal loss, as well as microglial activation in the hypothalamus, due to dietary-induced obesity. Microglia, the resident immune cells in the brain, are responsible for maintaining the brain homeostasis and, thus, providing an optimal environment for neuronal function. Interestingly, in obesity, microglial cells not only get activated in the hypothalamus but in other brain regions as well. Obesity is also highly associated with changes in hippocampal function, which could ultimately result in cognitive decline and dementia. Moreover, changes have also been reported in the striatum and cortex. Microglial heterogeneity is still poorly understood, not only in the context of brain region but, also, age and sex. This review will provide an overview of the currently available data on the phenotypic differences of microglial innate immunity in obesity, dependent on brain region, sex and age. 相似文献
243.
Jos R. Quintana Juan A. Ciller Felipe J. Serna 《Propellants, Explosives, Pyrotechnics》1992,17(3):106-109
Thermal behaviour of HMS/RDX mixtures is studied by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). It has been found that the temperature of polymorphic transformation of HMX shows an increase due to the presence of RDX. The enthalpies of the enothermic transformations depend on the composition of the mixture, and up to 30% RDX there is a linear relationship. The formation of an eutectic with a composition of 30/70 (HMX/RDX) is postulated to explain the melting processes. 相似文献
244.
Alma Rosa Lezama Toledo Germn Rivera Monroy Felipe Esparza Salazar Jea-Young Lee Shalini Jain Hariom Yadav Cesario Venturina Borlongan 《International journal of molecular sciences》2022,23(3)
Human lifestyle and dietary behaviors contribute to disease onset and progression. Neurodegenerative diseases (NDDs), considered multifactorial disorders, have been associated with changes in the gut microbiome. NDDs display pathologies that alter brain functions with a tendency to worsen over time. NDDs are a worldwide health problem; in the US alone, 12 million Americans will suffer from NDDs by 2030. While etiology may vary, the gut microbiome serves as a key element underlying NDD development and prognosis. In particular, an inflammation-associated microbiome plagues NDDs. Conversely, sequestration of this inflammatory microbiome by a correction in the dysbiotic state of the gut may render therapeutic effects on NDDs. To this end, treatment with short-chain fatty acid-producing bacteria, the main metabolites responsible for maintaining gut homeostasis, ameliorates the inflammatory microbiome. This intimate pathological link between the gut and NDDs suggests that the gut-brain axis (GBA) acts as an underexplored area for developing therapies for NDDs. Traditionally, the classification of NDDs depends on their clinical presentation, mostly manifesting as extrapyramidal and pyramidal movement disorders, with neuropathological evaluation at autopsy as the gold standard for diagnosis. In this review, we highlight the evolving notion that GBA stands as an equally sensitive pathological marker of NDDs, particularly in Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis and chronic stroke. Additionally, GBA represents a potent therapeutic target for treating NDDs. 相似文献
245.
Jeisson E.Otero-Leal John Cortés-Romero Efredy Delgado Aguilera Felipe Galarza-Jimenez Alexander Jimenez-Triana 《控制理论与技术(英文版)》2021,19(1):127-141
An adaptation of the active disturbance rejection control(ADRC)approach is applied to a fractional-order system with a flat output.Albeit the rather scarce info... 相似文献
246.
Caroline Busatta Vaz de Paula Seigo Nagashima Vanessa Liberalesso Mariana Collete Felipe Paes Gomes da Silva Alessandro Gonalves Gomes Oricil Giovanna Silva Barbosa Guilherme Vieira Cavalcante da Silva David Batista Wiedmer Felipe da Silva Dezidrio Lucia Noronha 《International journal of molecular sciences》2022,23(1)
Acute respiratory distress syndrome (ARDS) followed by repair with lung remodeling is observed in COVID-19. These findings can lead to pulmonary terminal fibrosis, a form of irreversible sequelae. There is evidence that TGF-β is intimately involved in the fibrogenic process. When activated, TGF-β promotes the differentiation of fibroblasts into myofibroblasts and regulates the remodeling of the extracellular matrix (ECM). In this sense, the present study evaluated the histopathological features and immunohistochemical biomarkers (ACE-2, AKT-1, Caveolin-1, CD44v6, IL-4, MMP-9, α-SMA, Sphingosine-1, and TGF-β1 tissue expression) involved in the TGF-β1 signaling pathways and pulmonary fibrosis. The study consisted of 24 paraffin lung samples from patients who died of COVID-19 (COVID-19 group), compared to 10 lung samples from patients who died of H1N1pdm09 (H1N1 group) and 11 lung samples from patients who died of different causes, with no lung injury (CONTROL group). In addition to the presence of alveolar septal fibrosis, diffuse alveolar damage (DAD) was found to be significantly increased in the COVID-19 group, associated with a higher density of Collagen I (mature) and III (immature). There was also a significant increase observed in the immunoexpression of tissue biomarkers ACE-2, AKT-1, CD44v6, IL-4, MMP-9, α-SMA, Sphingosine-1, and TGF-β1 in the COVID-19 group. A significantly lower expression of Caveolin-1 was also found in this group. The results suggest the participation of TGF-β pathways in the development process of pulmonary fibrosis. Thus, it would be plausible to consider therapy with TGF-β inhibitors in those patients recovered from COVID-19 to mitigate a possible development of pulmonary fibrosis and its consequences for post-COVID-19 life quality. 相似文献
247.
Anderson Luiz-Ferreira Maira Cola Victor Barbastefano Felipe Meira de-Faria Ana Beatriz A. de Almeida Elisangela Farias-Silva Tamara Regina Calvo Clélia A. Hiruma-Lima Wagner Vilegas Alba Regina M. Souza-Brito 《International journal of molecular sciences》2012,13(11):14973-14991
The present study evaluated the antiulcerogenic activity and mechanisms of the aqueous (AqF 100 mg/kg) and ethyl acetate (AcF 50 mg/kg) fractions from Indigofera truxillensis leaves. This dose was selected to assess its activity on ulcer healing and its action on gastric acid and mucus secretion, prostaglandin production and antioxidant enzyme activity (superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GSH-Rd)). Gastric ulcer was induced by absolute ethanol. Antisecretory action, mucus and prostaglandin production, healing and antioxidant enzyme activities were evaluated for both fractions. AqF and AcF significantly inhibited the gastric mucosal damage caused by ethanol. This effect was statistically significant at 100 and 50 mg/kg compared with the vehicle. Neither fraction interfered with gastric secretion. AcF increased the PGE2 production, and both fractions increased mucus production. l-NAME did not alter the gastroprotection exerted by the fractions, but N-ethylmaleimide attenuated only AcF. In the ischemia/reperfusion model both fractions inhibited the mucosal damage. AcF increased SOD, GSH-Px and GSH-Rd activity, but AqF increased only SOD and GSH-Px. In the acetic acid-induced ulcer model AcF only accelerated ulcer healing. These results showed that Indigofera truxillensis acted as a gastroprotective agent, stimulating protective factors and antioxidants enzymes. 相似文献
248.
Thermoplastic polyurethane synthesis with modified montmorillonite prepared by torque rheometry: Investigation of morphological,thermal, chemical,and physical properties 下载免费PDF全文
In this study, samples of thermoplastic polyurethane (TPU) were synthesized by reactive processing in an instrumented batch mixer with 0, 1, 2, 5, and 10 wt % of organophilic montmorillonite (OMMT) clay. Fourier transform infrared spectroscopy confirmed the obtainment of TPU. Transmission electron microscopy showed several types of clay dispersion. Analysis by X‐ray diffraction revealed modifications in the TPU microstructure, a reduction in the degree of crystallinity, and an increase in the crystal size. Dynamic mechanical properties showed that the incorporation of OMMT has a strong influence on the storage and loss moduli obtained for the TPU matrix. The incorporation of OMMT also altered the crystallization and thermal stability of the TPU. With the use of the Flynn–Wall–Ozawa method it was observed that the nanoclay had a higher apparent activation energy. The results obtained applying the Criado method indicated that the solid state reaction is essentially controlled by geometric contraction, random nucleation with one nucleus for each individual particle and diffusion. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42640. 相似文献
249.
Celia Castillo-Blas Consuelo Alvarez-Galvan Ines Puente-Orench Alba Garcia-Sanchez Freddy E.Oropeza Enrique Gutirrez-Puebla Angeles Monge Victor A.de la Pena-O'hea Felipe Gandara 《Nano Research》2021,14(2):493-500
The precise control on the combination of multiple metal atoms in the structure of metal-organic frameworks(MOFs)endowed by reticular chemistry,allows the obtaining of materials with compositions that are programmed for achieving enhanced reactivity.The present work illustrates how through the transformation of MOFs with desired arrangements of metal cations,multi-metal spinel oxides with precise compositions can be obtained,and used as catalyst precursor for the reverse water-gas shift reaction.The differences in the spinel initial composition and structure,determined by neutron powder diffraction,influence the overall catalytic activity with changes in the process of in s itu formation of active,metal-oxide supported metal nanoparticles,which have been monitored and characterized with in situ X-ray diffraction and photoelectron spectroscopy studies. 相似文献
250.
Goodman Lisa A.; Koss Mary P.; Fitzgerald Louise F.; Russo Nancy Felipe; Keita Gwendolyn Puryear 《Canadian Metallurgical Quarterly》1993,48(10):1054
This Psychology in the Public Forum section, authored by the American Psychological Association's Committee on Women in Psychology's Task Force on Male Violence Against Women and by Senator Joseph Biden, examines the prevalence, impact, and public policy dimensions of physical assault, sexual assault, and sexual harassment of women. This introduction reviews common themes that emerge from the articles that follow. It concludes by emphasizing that the problem of violence against women cannot be fully understood, let alone solved, by focusing exclusively on individual psychology. Only by changing the social and cultural institutions that have given rise to the problem can a lasting solution be achieved. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献