Identification of analytic signals

This paper is devoted to the identification of analytic signals and to find a solution to the following problem. Given a realization of an analytic signal, it is necessary to find the analytic function by which the signal is described. The proposed approach to this problem is based on relatively simple relationships existing between many analytic signals and their respective derivatives. These relationships are closely related to the properties of the dynamic systems which generate the signals under investigation. Simple identification procedures are described and tested by means of computer simulation.     

广东科技期刊稿约中的审稿时间的调查和分析

调查了广东部分科技期刊稿约中的审稿时间，发现其中存在一些问题亟待解决。解决问题的关键在于签订著作权合同。规范期刊社和作者之间的著作权关系，严格依法办事。     

Environment and Policy Factors Shaping Global E-Commerce Diffusion: A Cross-Country Comparison

This article examines the key global, environmental and policy factors that act as determinants of e-commerce diffusion. It is based on systematic comparison of case studies from 10 countries--Brazil, China, Denmark, France, Germany, Mexico, Japan, Singapore, Taiwan, and the United States. It finds that B2B e-commerce seems to be driven by global forces, whereas B2C seems to be more of a local phenomenon. A preliminary explanation for this difference is that B2B is driven by global competition and MNCs that "push" e-commerce to their global suppliers, customers, and subsidiaries. This in turn creates pressures on local companies to adopt e-commerce to stay competitive. In contrast, B2C is "pulled" by consumer markets, which are mainly local and therefore divergent. While all consumers desire convenience and low prices, consumer preferences and values, national culture, and distribution systems differ markedly across countries and define differences in local consumer markets. These findings support the transformation perspective about globalization and its impacts. In terms of policy, the case studies suggest that enabling policies such as trade and telecommunications liberalization are likely to have the biggest impact on e-commerce, by making ICT and Internet access more affordable to firms and consumers, and increasing pressure on firms to adopt e-commerce to compete. Specific e-commerce legislation appears not to have as big an impact, although inadequate protection for both buyers and sellers in some countries suggests that mechanisms need to be developed to ensure greater confidence in doing business online.     

Serum oestradiol in women with carcinomas of the breast and uterine cervix

Endogenous oestrogens are thought to be involved in breast cancer, but few studies could show the direct relationship between hormones and pathological process of the disease. In the present study, oestradiol was estimated in the serum of pre-and postmenopausal breast cancer patients along with normal healthy controls and patients with carcinoma of the uterine cervix which is not dependent on oestrogens. Premenopausal patients with breast cancer showed higher levels of oestradiol as compared to premenopausal control women as well as cervical cancer patients. Whereas, no statistically significant differences were observed in serum oestradiol levels amongst postmenopausal groups of breast cancer, cervical cancer and normal women. The result of the study reflects the association of oestradiol as well as its difference in the pathological events of pre and postmenopausal breast cancer.     

On the notions of ambiguity and information loss

One of the fundamental problems in information science is to distinguish various objects (such as books or journal articles) on the basis of associated values (such as authors and titles). Where the values fail to distinguish two distinct objects we say that the objects are ambigious under the given value assignment. To obtain a measure of ambiguity, it is only necessary to count the number of ways that the objects can be arranged for each set of ambiguous objects, multiply these counts and take logarithms. It is shown that such an approach leads to a measure in the formal sense and that the measure depends only on the definition of equality of values so that it can be simply extended to sets of values and ordered sets of values. It is also shown that it is possible to construct a function of ambiguity that one can call “information” and that the information loss that occurs when distinct values are grouped into equivalence classes (as in the use of search and sort keys) is also a measure. Finally, it is shown that ambiguity and information as here defined are directly related to Shannon's definition of “information” thus tieing this approach to that portion of information theory associated with the derivation of optimal distributions frequently used in information science models.     

Hyperlipidemia in guinea pigs induced by chronic vitamin C deficiency

Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood lipid profile which could promote atherogenesis.     

Study of adenosine deaminase activity in various arthritic conditions

Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis specially tubercular in initial stages.     

Promoting doctoral students' research self-efficacy: combining academic guidance with autonomy support

A diverse sample of doctoral students completed an on-line questionnaire assessing their supervisors' academic, personal and autonomy support and their research self-efficacy. The more task-related help and personal support students received, the more positively they evaluated their supervision. The degree to which supervisors encouraged students to think and act autonomously (autonomy support) was not uniquely associated with students' supervision satisfaction but predicted greater research self-efficacy. A combination of high levels of autonomy and academic support was associated with the highest levels of research self-efficacy, whereas when greater levels of personal support were accompanied by low levels of autonomy support, students reported lower research self-efficacy. These results indicate that effective doctoral supervision involves supporting students to voice and act on their own ideas while simultaneously providing guidance on how to complete research tasks.