Symmetry properties of tetraammine platinum（Ⅱ） with C2v and C4v point groups     

Moghani GA  Ashrafi AR  Hamadanian M 《Journal of Zhejiang University. Science. B》2005,6(3):222-226

Let G be a weighted graph with adjacency matrix A=[aij]. An Euclidean graph associated with a molecule is defined by a weighted graph with adjacency matrix D=[d/ij], where for i≠j, dij is the Euclidean distance between the nuclei i and j. In this matrix dij can be taken as zero if all the nuclei are equivalent. Otherwise, one may introduce different weights for different nuclei.Balasubramanian (1995) computed the Euclidean graphs and their automorphism groups for benzene, eclipsed and staggered forms of ethane and eclipsed and staggered forms of ferroeene. This paper describes a simple method, by means of which it is possible to calculate the automorphism group of weighted graphs. We apply this method to compute the symmetry of tetraammine platinum(Ⅱ) with C2v and C4v point groups.  相似文献   

Antagonistic interaction between <Emphasis Type="Italic">Trichoderma asperellum</Emphasis> and <Emphasis Type="Italic">Phytophthora capsici</Emphasis> in vitro     

Heng Jiang  Liang Zhang  Jing-ze Zhang  Mohammad Reza Ojaghian  Kevin D. Hyde 《Journal of Zhejiang University. Science. B》2016,17(4):271-281

Phytophthora capsici is a phytopathogen that causes a destructive pepper blight that is extremely difficult to control. Using a fungicide application against the disease is costly and relatively ineffective and there is also a huge environmental concern about the use of such chemicals. The genus Trichoderma has been known to have a potential biocontrol issue. In this paper we investigate the mechanism for causing the infection of T. asperellum against P. capsici. Trichoderma sp. (isolate CGMCC 6422) was developed to have a strong antagonistic action against hyphae of P. capsici through screening tests. The strain was identified as T. asperellum through using a combination of morphological characteristics and molecular data. T. asperellum was able to collapse the mycelium of the colonies of the pathogen through dual culture tests by breaking down the pathogenic hyphae into fragments. The scanning electron microscope showed that the hyphae of T. asperellum surrounded and penetrated the pathogens hyphae, resulting in hyphal collapse. The results show that seven days after inoculation, the hyphae of the pathogen were completely degraded in a dual culture. T. asperellum was also able to enter the P. capsici oospores through using oogonia and then developed hyphae and produced conidia, leading to the disintegration of the oogonia and oospores. Seven days after inoculation, an average 10.8% of the oospores were infected, but at this stage, the structures of oospores were still intact. Subsequently, the number of infected oospores increased and the oospores started to collapse. Forty-two days after inoculation, almost all the oospores were infected, with 9.3% of the structures of the oospores being intact and 90.7% of the oospores having collapsed.  相似文献   

Learning communities and fair trade in doctorates and development: report of a collaborative project     

Janinka Greenwood  Safayet Alam  Abu Nayeem Mohammad Salahuddin  Mollah Mohammed Haroon-Ar Rasheed 《Globalisation, Societies & Education》2016,14(1):49-67

This article reports the second stage of a study examining an academic partnership in which Bangladeshi doctoral students in a western university focus their research in the grounded context of Bangladesh and investigate the processes for change. After briefly outlining the previous published stage which examined the academic trade in higher education with developing countries, the article builds on the concept of fair academic trade to critically reflect on the development of a doctoral learning community, a publication project and three specific doctoral studies. The methodological approach is one of participatory action research, with focus on critical reflection on practice.  相似文献   

Learner satisfaction,engagement and performances in an online module: Implications for institutional e-learning policy     

Rajabalee  Yousra Banoor  Santally  Mohammad Issack 《Education and Information Technologies》2021,26(3):2623-2656

Education and Information Technologies - There has been debates related to online and blended learning from a perspective of learner experiences in terms of student satisfaction, engagement and...  相似文献   

Enumeration of lymphocyte subsets using flow cytometry: Effect of storage before and after staining in a developing country setting     

Sanju Jalla  Sunil Sazawal  Salkat Deb  robert E. Black  Satya Narayan Das  Archana Sarkar  Maharaj K. Bhan 《Indian journal of clinical biochemistry : IJCB》2004,19(2):95-99

Lymphocyte subset estimations by flow cytometry in population-based studies require transportation of samples from the field site to the laboratory. As samples arrive late in the day they have to wait overnight before being processed. The effect of two possible approaches, sample storage for 24 h before staining and immediate staining with analysis after 24 h and 48 h were evaluated. Two sets of experiments were performed with EDTA (ethylenediamine tetra-acetate) anticoagulated peripheral blood. In the first experiment, after collection, each sample was divided into two portions. One portion was stained at the time of blood collection and the other 24 h later after keeping it at room temperature (38–45°C). In the second experiment, blood samples were stained within 1–2 h. Each sample was analyzed immediately upon completion of staining process and subsequently after 24 h and 48 h of storage at 4°C. Results suggest that blood collected in EDTA can be processed using whole blood lysis method, after storage at room temperature (38–45°C) for 24 h with some but not significant alteration in T-cell subsets. Storage at 4°C after staining for 24 h results in a lesser and insignificant loss of cells or alteration of T-cell subsets and may be the method of choice.  相似文献   

THE EPISTEMIC VALUE OF CURIOSITY   总被引：1，自引：0，他引：1  

Frederick F. Schmitt  Reza Lahroodi 《Educational theory》2008,58(2):125-148

A bstract .  In this essay, Frederick Schmitt and Reza Lahroodi explore the value of curiosity for inquiry and knowledge. They defend an appetitive account of curiosity, viewing curiosity as a motivationally original desire to know that arises from having one's attention drawn to the object and that in turn sustains one's attention to it. Distinguishing curiosity from wonder, the authors explore several sources of the epistemic value of curiosity. First, curiosity is tenacious: curiosity whether a proposition is true leads to curiosity about related issues, thereby deepening our knowledge. Second, it is to some extent biased in favor of topics in which we already have a practical or epistemic interest. Third, and most important, curiosity is largely independent of our interests: it fixes our attention on objects in which we have no antecedent interest, thereby broadening our knowledge. Schmitt and Lahroodi elucidate the value of curiosity by outlining its role in levels of development — an approach indebted to John Dewey's explanation of the value of curiosity. Finally, they raise some questions about the implications of their account for educational practice.  相似文献   

Malaysian university students' attitudes to academic dishonesty and business ethics     

Zauwiyah Ahmad  Maimun Simun  Junaini Mohammad 《Asia Pacific Journal of Education》2008,28(2):149-160

Academic dishonesty is believed to have predictive ability for subsequent behaviours in the workplace. This study adds to the literature by investigating Malaysian business students' attitudes to academic dishonesty and their attitudes to ethics issues in business. This study also explores the association between these two constructs. The form of academic dishonesty being investigated here is related to assignments, quizzes, and examinations. Employing data collected from 153 business students from different academic years, this exploratory study concludes that business students may have found that some level of dishonesty is acceptable in some academic settings as well as in business settings. The study's outcomes highlight the possibility of using students' attitudes to academic dishonesty to explain their attitudes to ethics in business contexts. The findings of this study, to a certain extent, indicate that years spent in business education might contribute to such unfavourable attitudes. This exploratory study also draws attention to several issues related to the teaching of ethics within business education.  相似文献   

Effects of within-class ability grouping on social interaction,achievement, and motivation     

Mohammad?Saleh  Ard?W.?LazonderEmail author  Ton?De Jong 《Instructional Science》2005,33(2):105-119

This study examined how grouping arrangements affect students achievement, social interaction, and motivation. Students of high, average and low ability were randomly assigned to homogeneous or heterogeneous ability groups. All groups attended the same plant biology course. The main results indicate that low-ability students achieve more and are more motivated to learn in heterogeneous groups. Average-ability students perform better in homogeneous groups whereas high-ability students show equally strong learning outcomes in homogeneous and heterogeneous groups. Results on social interaction indicate that heterogeneous groups produce higher proportions of individual elaborations, whereas homogeneous groups use relatively more collaborative elaborations. In the discussion, these differences in social interaction are used to explain the differential effects of grouping arrangements on achievement scores. Practical implications are discussed and topics for further research are advanced.  相似文献   

A system operator theorem on positive real operators     

F.M. Reza 《Journal of The Franklin Institute》1983,316(3):279-290

A new theorem expands the domain of the scalar immittance functions Z(p) to the operator Z(T) where T(s) is an invertible linear passive n-port system. Elements R, L, C of Z(p) are replaced by operators RI, LT, and [CT] ^{- 1}. All frequency transformations may be considered contained in this theorem when T is a scalar.  相似文献   

Different effects of L-arginine on morphine tolerance in sham and ovariectomized female mice     

Karami R  Hosseini M  Khodabandehloo F  Khatami L  Taiarani Z 《Journal of Zhejiang University. Science. B》2011,12(12):1016-1023

Objective  

The roles of gonadal hormones and nitric oxide (NO) on the analgesic effects of morphine, tolerance to morphine, and their interactions have been widely investigated. In the present study, the effect of l-arginine (an NO precursor) on morphine tolerance in sham and ovariectomized (OVX) female mice was investigated.  相似文献