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排序方式: 共有2304条查询结果,搜索用时 14 毫秒
1.
Daniela Frasca Maria Romero Alain Diaz Denisse Garcia Seth Thaller Bonnie B. Blomberg 《International journal of molecular sciences》2021,22(4)
Senescent cells accumulate in the adipose tissue (AT) of individuals with obesity and secrete multiple factors that constitute the senescence-associated secretory phenotype (SASP). This paper aimed at the identification of B cells with a SASP phenotype in the AT, as compared to the peripheral blood, of individuals with obesity. Our results show increased expression of SASP markers in AT versus blood B cells, a phenotype associated with a hyper-metabolic profile necessary to support the increased immune activation of AT-derived B cells as compared to blood-derived B cells. This hyper-metabolic profile is needed for the secretion of the pro-inflammatory mediators (cytokines, chemokines, micro-RNAs) that fuel local and systemic inflammation. 相似文献
2.
Load testing of applications is an important and costly activity for software provider companies. Classical solutions are very difficult to set up statically, and their cost is prohibitive in terms of both human and hardware resources. Virtualized cloud computing platforms provide new opportunities for stressing an application's scalability, by providing a large range of flexible and less expensive (pay‐per‐use model) computation units. On the basis of these advantages, load testing solutions could be provided on demand in the cloud. This paper describes a Benchmark‐as‐a‐Service solution that automatically scales the load injection platform and facilitates its setup according to load profiles. Our approach is based on: (i) virtualization of the benchmarking platform to create self‐scaling injectors; (ii) online calibration to characterize the injector's capacity and impact on the benched application; and (iii) a provisioning solution to appropriately scale the load injection platform ahead of time. We also report experiments on a benchmark illustrating the benefits of this system in terms of cost and resource reductions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
3.
Lai-Ying Leong Teck-Soon Hew Keng-Boon Ooi Alain Yee Loong Chong Voon-Hsien Lee 《Information & Management》2021,58(2):103416
This paper examines what influences trust in mobile social commerce environment. Drawing on trust-based acceptance model (i.e. cognitive and emotional trust) and online review features (i.e. profile photo, linguistic style, and reported experience), we examine how these factors affect trust in mobile social commerce. Hypotheses were tested using survey data. The results of our model showed that there are significant influences of profile photo, reported experience, cognitive, and emotional trust towards trust in ms-commerce. This work contributes to existing literature by examining the roles of previous trust in mobile payments and online reviews on trust in mobile social commerce. 相似文献
4.
Igboamalu Frank Nonso Ndjiongue Alain Richard Ferreira Hendrik Christoffel 《Telecommunication Systems》2020,73(4):521-530
Telecommunication Systems - Signals from indoor access points in a wireless fidelity suffer from high attenuation as a result of the thick walls and metal structures in the multilevel-storey... 相似文献
5.
Minh Lequan Rose Marie Lequan Kathleen Chane-ching Anne-claude Callier Marguerite Barzoukas Alain Fort 《Advanced functional materials》1992,1(5):243-247
Samples of {4-(dimethylamino) stilben Z & E 4'-yl} dimesityl borane (BNS) were synthesised and investigated for their non-linear optical properties. The results show that the quadratic hyperpolarisability of the Z-isomer is smaller than that of the E-isomer, the beta value found for the latter being as high as 60 × 10?30 esu. 相似文献
6.
Non-contact handling in microassembly: Acoustical levitation 总被引:1,自引:0,他引:1
Microassembly is currently of the utmost importance in industry. Nevertheless, the classical assembly processes are no longer usable for very small components, typically ranging from 10 m to 10 mm, since usually neglected surface forces disturb the handling task by inducing adhesion between the component and the gripper. A promising alternative to tackle surface forces consists in levitating the handled component. The various advantages of this contactless handling method are reviewed here and justify the choice of this approach. Consequently, the numerous physical principles suitable for contactless handling are briefly described together with their limitations. The evaluation shows that acoustic levitation is best fitted in the case of microassembly. A classification of literature applications is presented hereafter with special focus on acoustic levitation. Finally, the most common models of acoustical levitation are inspected in a general way. The described models come within the scope of non-linear acoustics. 相似文献
7.
Discusses problems involved in collecting data based on observation of small groups. The example of a study of manifestations of cooperation in groups of preschoolers (aged 21–57 mo) is used for illustration. Statistical treatment of observation data and global analysis of data are considered. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Frdric Ampe Alain Brauman Serge Treche Aurelien Agossou 《Journal of the science of food and agriculture》1994,65(3):355-361
Retting, a spontaneous and traditional fermentation of cassava roots in Central Africa, was optimised in terms of time and the quality of the end-product. Optimal conditions were achieved by using an experimental research methodology. Temperature is the most influential factor, with an optimum of 34°C for quicker retting. The roots should be peeled and soaked in water immediately after harvesting to increase the quality of cassava foods. Inoculation of water with juice from a prior retting helps in cassava detoxification but has no influence on the time or the quality of foo-foo. Foo-foo samples had the most favourable organoleptic quality when an incubation temperature of between 28 and 37°C was used. Using optimal conditions, retting time was reduced 3-fold, and foo-foo of high and constant quality could be processed. 相似文献
9.
10.
The ring-opening polymerization of hexamethylcyclodisilazane (D2NMe), initiated by methyl triflate in 1,2-dichloroethane, forms in the first, fast kinetic step both linear polymer and cyclic dimer (D4NMe). Subsequently a slow depolymerization process occurs leading to exclusively cyclotrisilazane (D3NMe). On the basis of kinetic measurements carried out using an adiabatic calorimetric technique and complementary experiments, mechanisms of both propagation, cyclization and back-biting reactions are proposed. The influence of the reaction temperature was also studied; it is demonstrated that, at low temperature, polymerization does not lead to cyclic oligomer formation. In such conditions, the polymerization presents a ‘living’ character. 相似文献