Mitochondria can power cells to life and death     

Nand K. Sah  Tarvinder K. Taneja  Seyed E. Hasnain 《Resonance》2000,5(4):74-84

Mitochondria serve as power houses of cells but they also possess ‘covered’ knives to kill the cells. A number of intrinsic and extrinsic factors exist which regulate cell killing by mitochondria. Caspases are comparable to a surgeon’s knife, which can be used to sculpt organisms, get rid of wayward, redundant and incorrigibly damaged cells, but can spell doom if not controlled properly.  相似文献   

Situational and personal influence on attitude change following ethnic contact     

Yehuda Amir  Chana Garti 《Int J Intercult Relat》1977,1(2):58-75

The study undertook to examine the validity in Israel of several conclusions reached by investigators in the United States on the effect of intergroup contact on change in ethnic attitudes, as well as to extend contact research to topics which heretofore have received only scant attention. There were 100 subjects: 12-year-old Israeli girls of different ethnic background, participating in a summer camp. Results indicated that (1) as a result of contact, a positive change in attitude of the high status towards the low-status group occurred with regard to people and activities both related and not related to the contact situation, (2) only subjects without previous ethnic contact showed changes, (3) enjoyment of the contact situation was related to attitude change, while (4) authoritarianism was not related to attitude change.  相似文献   

Threshold of Withdrawal from Schoolwork among Children of Divorced Parents     

Joseph Guttmann  Tova Amir  Michael Katz 《教育心理学》1987,7(4):295-302

Abstract The principal aim of the present study was to examine whether there is a difference of withdrawal threshold between children of divorced parents and children from intact families as regards schoolwork. Three different school‐type tests, designed to be long and frustrating, were administered to two groups of children. One group consisted of 31 children of divorced parents (15 boys and 16 girls); the second consisted of children from intact families and was of equal size and had a matching number of children of both sexes. There were three dependent variables: level of achievement, level of determination and the time spent on the test. The main results show that children of divorced parents have lower levels of achievement and lower withdrawal thresholds than do children from intact families. These findings are presented in the context of a consideration both of the children's experience and interpretation of their parents’ divorce and of the generalisability of the concept of withdrawal threshold.  相似文献   

An integrated group decision-making process for supplier selection and order allocation using multi-attribute utility theory and linear programming     

Amir Sanayei  S. Farid Mousavi  Ali Mohaghar 《Journal of The Franklin Institute》2008,345(7):731-747

Supplier selection is a complex multi-criteria problem including both quantitative and qualitative factors. In order to select the best suppliers it is necessary to make a trade-off between these factors, some of which may be in conflict and may also be uncertain. In this problem if suppliers have capacity or other different constraints, two problems will exist: which suppliers are best and how much should be purchased from each selected supplier.In this paper an integrated approach of multi-attribute utility theory (MAUT) and linear programming (LP) is proposed for rating and choosing the best suppliers and defining the optimum order quantities among selected ones in order to maximize total additive utility. A numerical example is proposed to illustrate an application of the proposed method.  相似文献   

Robust simultaneous fault detection and control for a class of nonlinear stochastic switched delay systems under asynchronous switching     

Hossein Shokouhi-Nejad  Amir Rikhtehgar Ghiasi  Mohammad Ali Badamchizadeh 《Journal of The Franklin Institute》2017,354(12):4801-4825

This paper concerns the simultaneous fault detection and control (SFDC) problem for a class of nonlinear stochastic switched systems with time-varying state delay and parameter uncertainties. The switching signal of detector/controller unit (DCU) is assumed to be with switching delay, which results in the asynchronous switching between the subsystems and DCU. By constructing a switching strategy depending on the state and switching delays, new sufficient conditions expressed by a set of linear matrix inequalities (LMIs) is derived to design DCU gains. This problem is formulated as an H_∞ optimization problem and both mean square exponential stability and fault detection of augmented system are considered. A numerical example is finally exploited to verify the effectiveness and potential of the achieved scheme.  相似文献   

Preparation,Characterization and Cytotoxic Effects of Pegylated Nanoliposomal Containing Carboplatin on Ovarian Cancer Cell Lines     

Meysam Ebrahimifar  Amir Nili-Ahmadabadi  Azim Akbarzadeh  Hasan Ebrahimi Shahemabadi  Majid Hasanzadegan  Hemen Moradi-Sardareh  Hassan Madadizadeh  Jalal Rezaee-diyan 《Indian journal of clinical biochemistry : IJCB》2017,32(2):230-234

Carboplatin is a chemotherapeutic agent used against various malignancies such as ovarian carcinoma. The aim of this study is to improve the therapeutic efficacy of carboplatin using pegylated liposomal nanocarriers. Nanoparticles were synthesized using thin film hydration technique and characterized for shape morphology, particle size, zeta potential and drug-release properties. In the next step, A2780S and A2780CP ovarian cancer cell lines were used to determine the efficacy of nanodrug by MTT assay. The particle size and zeta potential of nanodrug were measured 244.3 ± 19.6 nm and ?22.9 ± 1.7 mV, respectively. High encapsulation capacity (78.6 ± 3.7 %) confirmed the efficiency of technique. The cytotoxicity results also showed that nanodrug compared to free drug improve the efficacy of carboplatin against both A2780S (P < 0.01) and A2780CP (P < 0.05) cell lines. In conclusion, the findings of our study suggested pegylated liposomal nanocarriers are proper for carboplatin delivery to ovarian cancer cell lines A2780S and A2780CP.  相似文献   

Group status and attitude change in desegregated classrooms     

Yehuda Amir  Shlomo Sharan  Miriam Rivner  Rachel Ben-ari  Aharon Bizman 《Int J Intercult Relat》1979,3(2):137-152

One thousand thirty-three ninth-grade students from Western and Middle-Eastern ethnic background in 30 classrooms responded to a questionnaire assessing ethnic attitudes. The questionnaire was administered at the beginning and again at the end of these students' first year in ethnically desegregated classrooms. No marked changes in ethnic attitudes were noted as a function of the students' individual academic or social status in the classroom, but there were noteworthy changes associated with the relative status in the classroom occupied by the students' ethnic groups. Positive attitude change among Western (majority) students occurred when both ethnic groups in the classroom were of equal status, and when the MiddleEastern (minority) group was of superior academic status to the Western group. Positive change among the Middle-Eastern group occurred when it occupied superior status in the classroom.  相似文献   

AFAR: adaptive fuzzy ant-based routing for communication networks     

Seyed Javad Mirabedini  Mohammad Teshnehlab  M. H. Shenasa  Ali Movaghar  Amir Masoud Rahmani 《浙江大学学报(A卷英文版)》2008,9(12):1666-1675

We propose a novel approach called adaptive fuzzy ant-based routing （AFAR）, where a group of intelligent agents （or ants） builds paths between a pair of nodes, exploring the network concurrently and exchanging obtained information to update the routing tables. Routing decisions can be made by the fuzzy logic technique based on local information about the current network state and the knowledge constructed by a previous set of behaviors of other agents. The fuzzy logic technique allows multiple constraints such as path delay and path utilization to be considered in a simple and intuitive way. Simulation tests show that AFAR outperforms OSPF, AntNet and ASR, three of the currently most important state-of-the-art algorithms, in terms of end-to-end delay, packet delivery, and packet drop ratio. AFAR is a promising alternative for routing of data in next generation networks.  相似文献   

Development of a Virtual Three-Dimensional Assessment Scenario for Anatomical Education     

Katerina Bogomolova  Amir H. Sam  Adam T. Misky  Chinmay M. Gupte  Paul H. Strutton  Thomas J. Hurkxkens  Beerend P. Hierck 《Anatomical sciences education》2021,14(3):385-393

In anatomical education three-dimensional (3D) visualization technology allows for active and stereoscopic exploration of anatomy and can easily be adopted into medical curricula along with traditional 3D teaching methods. However, most often knowledge is still assessed with two-dimensional (2D) paper-and-pencil tests. To address the growing misalignment between learning and assessment, this viewpoint commentary highlights the development of a virtual 3D assessment scenario and perspectives from students and teachers on the use of this assessment tool: a 10-minute session of anatomical knowledge assessment with real-time interaction between assessor and examinee, both wearing a HoloLens and sharing the same stereoscopic 3D augmented reality model. Additionally, recommendations for future directions, including implementation, validation, logistic challenges, and cost-effectiveness, are provided. Continued collaboration between developers, researchers, teachers, and students is critical to advancing these processes.  相似文献   

High school preparation for college biology in Israel     

Pinchas Tamir  Ruth Amir  Rachel Nussinovitz 《Higher Education》1980,9(4):399-408

The study reports the results of a questionnaire on the opinions of biology, medical and agricultural students regarding the nature of the contribution of high school biology to their study of biology in the university. It was found that most students value the contribution of high school biology to their learning, understanding and retention of new material. Students who specialized in high school biology and who studied an inquiry-oriented program in high school had definite advantages over the others. High school experiences were found to influence achievement in college biology to the extent to which the university courses were based upon prior knowledge.  相似文献