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排序方式: 共有2854条查询结果,搜索用时 15 毫秒
61.
Paola C. Bello-Medina Karina Corona-Cervantes Norma Gabriela Zavala Torres Antonio Gonzlez Marcel Prez-Morales Diego A. Gonzlez-Franco Astrid Gmez Jaime García-Mena Sofía Díaz-Cintra Gustavo Pacheco-Lpez 《International journal of molecular sciences》2022,23(15)
Alzheimer’s disease (AD) is a multifactorial pathology characterized by β-amyloid (Aβ) deposits, Tau hyperphosphorylation, neuroinflammatory response, and cognitive deficit. Changes in the bacterial gut microbiota (BGM) have been reported as a possible etiological factor of AD. We assessed in offspring (F1) 3xTg, the effect of BGM dysbiosisdysbiosis in mothers (F0) at gestation and F1 from lactation up to the age of 5 months on Aβ and Tau levels in the hippocampus, as well as on spatial memory at the early symptomatic stage of AD. We found that BGM dysbiosisdysbiosis with antibiotics (Abx) treatment in F0 was vertically transferred to their F1 3xTg mice, as observed on postnatal day (PD) 30 and 150. On PD150, we observed a delay in spatial memory impairment and Aβ deposits, but not in Tau and pTau protein in the hippocampus at the early symptomatic stage of AD. These effects are correlated with relative abundance of bacteria and alpha diversity, and are specific to bacterial consortia. Our results suggest that this specific BGM could reduce neuroinflammatory responses related to cerebral amyloidosis and cognitive deficit and activate metabolic pathways associated with the biosynthesis of triggering or protective molecules for AD. 相似文献
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63.
ABSTRACT In this paper, we present an aspect-oriented approach and propose a high-level language called SHL (Security Hardening Language) for the systematic security hardening of software. The primary contribution of this proposition is providing the software architects with the capabilities to perform security hardening by applying well-defined solutions and without the need to have expertise in the security solution domain. At the same time, the security hardening is applied in an organized and systematic way in order not to alter the original functionalities of the software. This is done by providing an abstraction over the actions required to improve the security of a program and adopting aspect-oriented programming to build and develop the solutions. SHL allows the developers to describe and specify the security hardening plans and patterns needed to harden systematically security into open source software. It is a minimalist language built on top of the current aspect-oriented technologies that are based on advice-poincut model and can also be used in conjunction with them. We explore the viability and relevance of our proposition by applying it into several security hardening case studies and presenting their experimental results. 相似文献
64.
Bassam Hammo Saleem Abuleil Steven Lytinen Martha Evens 《Computers and the Humanities》2004,38(4):397-415
The World Wide Web (WWW) today is so vast that it has become more and more difficult to find answers to questions using standard search engines. Current search engines can return ranked lists of documents, but they do not deliver direct answers to the user. The goal of Open Domain Question Answering (QA) systems is to take a natural language question, understand the meaning of the question, and present a short answer as a response based on a repository of information. In this paper we present QARAB, a QA system that combines techniques from Information Retrieval and Natural Language Processing. This combination enables domain independence. The system takes natural language questions expressed in the Arabic language and attempts to provide short answers in Arabic. To do so, it attempts to discover what the user wants by analyzing the question and a variety of candidate answers from a linguistic point of view. 相似文献
65.
Escalante A Giles-Gómez M Hernández G Córdova-Aguilar MS López-Munguía A Gosset G Bolívar F 《International journal of food microbiology》2008,124(2):126-134
In this study, the characterization of the bacterial community present during the fermentation of pulque, a traditional Mexican alcoholic beverage from maguey (Agave), was determined for the first time by a polyphasic approach in which both culture and non-culture dependent methods were utilized. The work included the isolation of lactic acid bacteria (LAB), aerobic mesophiles, and 16S rDNA clone libraries from total DNA extracted from the maguey sap (aguamiel) used as substrate, after inoculation with a sample of previously produced pulque and followed by 6-h fermentation. Microbiological diversity results were correlated with fermentation process parameters such as sucrose, glucose, fructose and fermentation product concentrations. In addition, medium rheological behavior analysis and scanning electron microscopy in aguamiel and during pulque fermentation were also performed. Our results showed that both culture and non-culture dependent approaches allowed the detection of several new and previously reported species within the alpha-, gamma-Proteobacteria and Firmicutes. Bacteria diversity in aguamiel was composed by the heterofermentative Leuconostoc citreum, L. mesenteroides, L. kimchi, the gamma-Proteobacteria Erwinia rhapontici, Enterobacter spp. and Acinetobacter radioresistens. Inoculation with previously fermented pulque incorporated to the system microbiota, homofermentative lactobacilli related to Lactobacillus acidophilus, several alpha-Proteobacteria such as Zymomonas mobilis and Acetobacter malorum, other gamma-Proteobacteria and an important amount of yeasts, creating a starting metabolic diversity composed by homofermentative and heterofermentative LAB, acetic and ethanol producing microorganisms. At the end of the fermentation process, the bacterial diversity was mainly composed by the homofermentative Lactobacillus acidophilus, the heterofermentative L. mesenteroides, Lactococcus lactis subsp. lactis and the alpha-Proteobacteria A. malorum. After a 6-h fermentation, 83.27% of total sugars detected after inoculation were consumed (228.4 mM hexose equivalents) and a carbon (C) recovery of 66.18% in fermentation products was estimated. They were produced 284.4 mM C as ethanol, 71.5 mM C as acetic acid and 19 mM C as lactic acid, demonstrating the presence of homo- and heterofermentative, acetic and alcoholic metabolisms in the final product. It was also found, after hydrolysis, that the exopolysaccharide produced during the fermentation was mainly composed by fructose residues, probably inulin or levan. 相似文献
66.
Torres Luis Vanderlei Naldi Marcos Antônio Zoqui Eugênio José 《Journal of Materials Science》2021,56(19):11541-11556
Journal of Materials Science - This study sought to analyze the semi-solid behavior of commercial 332 aluminum alloy during thixoforming in a mechanical eccentric press (thixoforging). The... 相似文献
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68.
J. Rodríguez‐Ramírez L. Mndez‐Lagunas A. Lpez‐Ortiz S. Sandoval Torres 《Journal of food science》2012,77(12):R146-R154
Abstract: This review presents the concepts involved in determining the density of foodstuffs, and summarizes the volumetric determination techniques used to calculate true density and apparent density in foodstuffs exposed to the drying process. The behavior of density with respect to moisture content (X) and drying temperature (T) is presented and explained with a basis in changes in structure, conformation, chemical composition, and second‐order phase changes that occur in the processes of mass and heat transport, as reported to date in the literature. A review of the empirical and theoretical equations that represent density is presented, and their application in foodstuffs is discussed. This review also addresses cases with nonideal density behavior, including variations in ρs and ρw as a function of the inside temperature of the material, depending on drying conditions (X, T). A compilation of studies regarding the density of dehydrated foodstuffs is also presented. 相似文献
69.
The aim of this paper is to examine how wine firms implement their marketing strategies based on the recognition of market opportunities by their Chief Executive Officers (CEOs). Firstly, we describe the marketing activities in 69 traditional Chilean wine firms. Then, in-depth interviews with CEOs of two wineries are analysed using cognitive maps to uncover the cognitive processes responsible for recognizing and executing market activities. Our findings indicate that there is a similar set of strategic resources across the wineries, but the CEOs’ different perceptions of the usefulness of these resources in the implementation of marketing strategies have led them to select diverse strategies to increasing both the price per bottle and wine sales. This paper makes two contributions. Firstly, we compare the benefit of implementing traditional and relational marketing strategies in the Chilean wine industry. Secondly, we show that the CEOs’ perception of feedback processes among the available resources affects the recognition of market opportunities and the marketing strategy in wine firms. 相似文献
70.
A total of 286 lactic acid bacteria isolated from goat’s dairy products in northwest of Argentina were characterized. Lactobacilli (38%) and cocci (62%) were identified according to morphological, physiological, and relevant technological properties. L. plantarum (14%) and Enterococcus (34%) were the predominant species. S. thermophilus, Pediococcus and L. plantarum were the highest acid producers. Eight strains of L. fermentum produced bacteriocins or metabolites similar to bacteriocins. The API-ZYM test was applied to 39 isolates. Eight strains were selected from their both technological properties and enzymatic activities for use as starter or adjunct culture in the manufacture of artisanal goat cheeses. 相似文献