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排序方式: 共有92条查询结果,搜索用时 15 毫秒
1.
The viability and β‐galactosidase activity of four Lactobacillus strains in milk drink containing gums during 28 days of refrigerated storage at 4 °C were assessed. The population of Lactobacillus rhamnosus GGB101 and Lactobacillus rhamnosus GGB103 were maintained, whereas the population of Lactobacillus reuteri DSM20016 and Lactobacillus reuteri SD2112 significantly decreased. The recommended level of 6 log CFU g?1 was exceeded for all tested trains throughout storage. The highest viable number of Lactobacillus rhamnosus GGB103 (8.76 ± 0.03 log CFU mL?1) was obtained in the product containing carrageenan–maltodextrin. The addition of guar–locust bean–carrageenan led to 20‐fold increase in the level of β‐galactosidase activity for L. rhamnosus GGB101 (1208 ± 2.12 Miller units mL?1) compared to the control (61 ± 2.83 Miller units mL?1). Our results suggested that gums could be added to milk to improve viability and enhance β‐galactosidase activity of Lactobacillus.  相似文献   
2.
The use of hydrogen as a fuel is increasing exponentially, and the most economical way to store and transport hydrogen for fuel use is as a high-pressure gas. Polymers are widely used for hydrogen distribution and storage systems because they are chemically inert towards hydrogen. However, when exposed to high-pressure hydrogen, some hydrogen diffuses through polymers and occupies the preexisting cavities inside the material. Upon depressurization, the hydrogen trapped inside polymer cavities can cause blistering or cracking by expanding these cavities. A continuum mechanics–based deformation model was deployed to predict the stress distribution and damage propagation while the polymer undergoes depressurization after high-pressure hydrogen exposure. The effects of cavity size, cavity location, and pressure inside the cavity on damage initiation and evolution inside the polymer were studied. The stress and damage evolution in the presence of multiple cavities was also studied, because interaction among cavities alters the damage and stress field. It was found that all these factors significantly change the stress state in the polymer, resulting in different paths for damage propagation. The effect of adding carbon black filler particles and plasticizer on the damage was also studied. It was found that damage tolerance of the polymer increases drastically with the addition of carbon black fillers, but decreases with the addition of the plasticizer.  相似文献   
3.
Adaptive perceptual color-texture image segmentation.   总被引:2,自引:0,他引:2  
We propose a new approach for image segmentation that is based on low-level features for color and texture. It is aimed at segmentation of natural scenes, in which the color and texture of each segment does not typically exhibit uniform statistical characteristics. The proposed approach combines knowledge of human perception with an understanding of signal characteristics in order to segment natural scenes into perceptually/semantically uniform regions. The proposed approach is based on two types of spatially adaptive low-level features. The first describes the local color composition in terms of spatially adaptive dominant colors, and the second describes the spatial characteristics of the grayscale component of the texture. Together, they provide a simple and effective characterization of texture that the proposed algorithm uses to obtain robust and, at the same time, accurate and precise segmentations. The resulting segmentations convey semantic information that can be used for content-based retrieval. The performance of the proposed algorithms is demonstrated in the domain of photographic images, including low-resolution, degraded, and compressed images.  相似文献   
4.
The mechanism behind the hypolipidemic effect of tetradecylthioacetic acid (CMTTD, a non-beta-oxidizable 3-thia fatty acid) was studied in hamsters fed a high cholesterol diet (2%), which resulted in hyperlipidemia. Treating hyperlipidemic hamsters with CMTTD resulted in a progressive hypocholesterolemic and hypotriacylglycerolemic effect. Decreased plasma cholesterol was followed by a 39% and 30% reduction in VLDL-cholesterol and LDL-cholesterol, respectively. In contrast, the HDL-cholesterol content was not affected, thus decreasing the VLDL-cholesterol/HDL-cholesterol and LDL-cholesterol/HDL-cholesterol ratios. 3-Hydroxy-3-methylglutaryl- (HMG) CoA reductase activity and its mRNA level were unchanged after CMTTD administration. Also, the LDL receptor and LDL receptor-related protein (LRP-4) mRNAs were unchanged. The decrease in plasma triacylglycerol was accompanied by a 45% and 56% reduction in VLDL-triacylglycerol and LDL-triacylglycerol, respectively. The hypolipidemic effect of CMTTD was followed by a 1.4-fold increase in mitochondrial fatty acid oxidation and a 2.3-fold increase in peroxisomal fatty acid oxidation. CMTTD treatment led to an accumulation of dihomo-gamma-linolenic acid (20:3n-6) in liver, plasma, very low density lipoprotein, and heart. Noteworthy, CMTTD accumulated more in the heart, plasma, and VLDL particles compared to the liver, and in the VLDL particle alpha-linolenic acid (18:3n-3) decreased whereas eicosatetraenoic acid (20:4n-3) increased. In addition, linoleic acid (18:2n-6) and the total amount of polyunsaturated fatty acids decreased, the latter mainly due to a decrease in n-6 fatty acids. The present data show that CMTTD was detected in plasma and incorporated into VLDL, liver, and heart. The relative incorporation (mol%) of CMTTD was heart > VLDL > liver. In conclusion, CMTTD causes both a hypocholesterolemic and hypotriacylglycerolemic effect in hyperlipidemic hamsters.  相似文献   
5.
Depression is a prominent complex psychiatric disorder, usually complicated through expression of comorbid conditions, with chronic pain being among the most prevalent. This comorbidity is consistently associated with a poor prognosis and has been shown to negatively impact patient outcomes. With a global rise in this condition presenting itself, the importance of discovering long-term, effective, and affordable treatments is crucial. Electroacupuncture has demonstrated renowned success in its use for the treatment of pain and is a widely recognized therapy in clinical practice for the treatment of various psychosomatic disorders, most notably depression. Our study aimed to investigate the effects and mechanisms of Acid-Saline (AS) inducing states of chronic pain and depression comorbidity in the cerebellum, using the ST36 acupoint as the therapeutic intervention. Furthermore, the role of TRPV1 was relatedly explored through the use of TRPV1−/− mice (KO). The results indicated significant differences in the four behavioral tests used to characterize pain and depression states in mice. The AS and AS + SHAM group showed significant differences when compared to the Control and AS + EA groups in the von Frey and Hargreaves’s tests, as well as the Open-Field and Forced Swimming tests. This evidence was further substantiated in the protein levels observed in immunoblotting, with significant differences between the AS and AS + SHAM groups when compared to the AS + EA and AS + KO groups being identified. In addition, immunofluorescence visibly served to corroborate the quantitative outcomes. Conclusively these findings suggest that AS-induced chronic pain and depression comorbidity elicits changes in the cerebellum lobules VI, VII, VIII, which are ameliorated through the use of EA at ST36 via its action on TRPV1 and related molecular pathways. The action of TRPV1 is not singular in CPDC, which would suggest other potential targets such as acid-sensing ion channel subtype 3 (ASIC3) or voltage-gated sodium channels (Navs) that could be explored in future studies.  相似文献   
6.
By a vote of 5–4 (with Justice Kennedy in the majority), the Supreme Court has reversed and remanded a regulation issued by the Environmental Protection Agency (EPA) under the Clean Air Act that limited emissions of mercury and other airborne toxics from electric power plants, because the agency failed to consider the costs of regulation at the start of the rulemaking process.1  相似文献   
7.
Yam (Dioscorea sp.) is a major source of food for millions of people in tropical and sub-tropical regions, especially in West and Central Africa where at least 60 million people depend on it. It is also a major source of income and an integral part of socio-cultural life. In addition to their food uses, some Dioscorea species are exploited for pharmaceutical products. Yam cultivation is undergoing intensification in many production zones leading to challenges in the management of soil fertility and structure, increasing pressure of diseases and pests (including weeds), and requirements for new varieties better suited to the changing biophysical and socio-economic circumstances. Greater attention also needs to be paid to raising labor productivity and improving access of producers to affordable and higher quality planting materials. These challenges, and the opportunities associated with the biology of the crop, need to be addressed more systematically and earnestly through collaborative research and development, and effective dissemination of the results to relevant stakeholders. The increasing capacity for, and international collaboration in, research and development on yam augur well for the future of the crop and the millions of people who depend on it.  相似文献   
8.
In this article, six faculty and students of color who participated in a panel discussion at a symposium during the National Multicultural Conference and Summit of 2003 talk about the barriers they encountered and continue to encounter in their graduate training and places of employment. They also discuss strategies they found to be effective, enhancing, and positive and suggest other possibilities. The contributors describe their relationships with dominant-group and minority peers and talk about how issues of social class, disability, and sexual orientation as well as color have been part of their experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Twenty-and 22-carbon fatty acids of the linoleic (n-6) and linolenic (n-3) acid families were measured in murine spermatogonia and preleptotene spermatocytes (early), pachytene primary spermatocytes (10) round spermatids (RS), condensing spermatids (CS) and Leydig cells enriched by staput velocity sedimentation at 1 G, followed by viable microflow sorting on the basis of light scatter and DNA content. 22: 5(n-6) increased progressively from 2 to 20% of total fatty acid in the progression of germinal cell differentiation, early »10»RS»CS, but decreased in mature sperm. The precursor 20:4(n-6) showed a roughly reciprocal relationship. 22:6(n-3) showed no significant correlation with cell type. 22:5(n-6) was found highest in triglycerides of later differentiation stages whereas 20:4(n-6) and 22:6(n-3) were found primarily in phospholipid in all cell fractions.  相似文献   
10.
Three cohorts of 10- to 14-year-old adolescents were sampled to obtain perceptions of their parents' conflict-resolution styles, their own conflict-resolution styles, and their behavioral adjustment, to test J. H. Grych and F. D. Fincham's (1990) cognitive-contextual model of the relationship of marital conflict to child adjustment. As found previously, boys and girls were not exposed to different levels or types of interparental conflict, although boys tended to blame themselves more. Adolescents' reports of their own conflict-resolution styles with siblings were clearly related to level and types of their more general adjustment levels. A series of regressions supported Grych and Fincham's model for internalizing problems (and avoidant resolution style) in adolescents; only minimal support was found with externalizing problems (and attacking resolution style). Gender-specific patterns of intergenerational transmission of resolution styles were found and are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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