2003国际橡塑展十二月北京举行展会规模再创高峰

<正> 被誉为大中华地区最具规模及最具代表性之国际塑橡展览会-‘第十七届中国国际塑料橡胶工业展览会’(简称‘2003国际橡塑展’)将于2003年12月4日至7日假北京中国国际展览中心举行。是次展会已是连续第十四年获得EUROMAP之中国独家赞助,多年来又得到多个海外及国内专业协会会之鼎力支持。 ‘国际橡塑展’自1983年举办至今,为中外从事塑料制品加工、原材料、助     

Dechlorination of polychlorinated biphenyls in industrial transformer oil by radiolytic and photolytic methods

Used electrical transformer oils containing low or high concentrations of polychlorinated biphenyls (PCBs) were treated using electron, gamma, and ultraviolet radiation, and the conditions for complete dechlorination were developed. Dechlorination was determined by analysis of the inorganic chloride formed and the concentrations of remaining PCBs. Transformer oil containing approximately 95 microg g(-1) PCB (approximately 3.5 mmol L(-1) Cl) is completely dechlorinated by irradiation with 600 kGy after the addition of 10% triethylamine (TEA). Transformer oil containing >800,000 microg g(-1) PCB (17.7 mol L(-1) Cl) requires an additional solvent to prevent solidification. When this oil is diluted with 2-propanol (2-PrOH) and TEA (v/v/v, 1/79/20), complete dechlorination is achieved with a dose of 2500 kGy. Ultraviolet photolysis of the same oil/2-PrOH/TEA solutions led to 90% dechlorination after exposure for 120 h in our experimental setup. Such yields were obtained by radiolysis with a dose of 2000 kGy (300 h in our Gammacell). Replacing TEA with KOH in 2-PrOH solutions greatly increases the yield of dechlorination in both the radiolytic and the photolytic experiments, demonstrating that a chain reaction plays a role in both of these treatment methods and suggesting that both methods deserve further consideration for large-scale application.     

Maternal folate supply and sex influence gene‐specific DNA methylation in the fetal gut

Scope : Epidemiological evidence supports the developmental origins of health and disease hypothesis that developmental under/over‐nutrition increases adulthood disease risk. Epigenetic markings are one potential mechanism mediating these effects. Altered folate supply may influence methyl group availability for DNA methylation. We reported low folate supply in utero was associated with reduced global DNA methylation in the murine small intestine of adult offspring. We hypothesised that aberrant methylation would be observed during early development. Methods and results : Female C57BL/6J mice were fed diets containing 2 mg folic acid/kg or 0.4 mg folic acid/kg 4 wk before mating and during pregnancy. At 17.5 day gestation, gene methylation in fetal gut was analysed by Pyrosequencing^®. Low folate reduced overall methylation of Slc394a by 3.4% (p=0.038) but did not affect Esr1 or Igf2 differentially methylated region (DMR) 1. There were sex‐specific differences in Slc394a and Esr1 methylation (2.4% higher in females (p=0.002); 4% higher in males (p=0.0014), respectively). Conclusion : This is the first study reporting causal effects of maternal folate depletion on gene‐specific methylation in fetal gut. These observations support reports that altered methyl donor intake during development affects DNA methylation in the offspring. The consequences of epigenetic changes for health throughout the life course remain to be investigated.     

Dietitians and eating disorders: an international issue

The prevalence of eating disorders is higher in university nutrition faculties than in other faculties. We examined beliefs about and approaches to eating disorders in nutrition education faculties around the world. We developed a questionnaire specifically for this project and distributed 664 copies electronically, using contact information obtained in collaboration with Dietitians of Canada and the International Confederation of Dietetic Associations. Using the 101 questionnaires returned from 14 countries, we found that 77% of respondents felt eating disorders are a concern among nutrition students; however, only 15% of programs had policies/procedures to help address these disorders. Forty-eight percent of respondents thought screening for eating disorders would be a good idea; however, 78% of them believed screening would involve ethical issues. In conclusion, eating disorders are a concern in nutrition faculties around the world, and while most feel something should be done, ethical dilemmas contribute to confusion over the best approach. More work is needed in this area.     

Blockade of NMDA receptors 2A subunit in the dorsal striatum impairs the learning of a complex motor skill.

Accumulating evidence proposes that the striatum, known to control voluntary movement, may also play a role in learning and memory. Striatum learning is thought to require long-lasting reorganization of striatal circuits and changes in the strength of synaptic connections during the memorization of a complex motor task. Whether the ionotropic glutamate receptor N-methyl-D-aspartate (NMDAR) contributes to the molecular mechanisms of these memory processes is still unclear. The aim of the present study was to investigate the role of striatal NMDAR and its subunit composition during the learning of the accelerating rotarod task in mice. To this end, we injected directly into the dorsal striatum of mice, via chronically implanted cannula, the NMDAR channel blocker MK-801 as well as the NR2A and NR2B subunit-selective antagonists NVP-AAM077 and Ro 25-6981, respectively, before rotarod training. There was no effect in the motor performances of mice treated with 1.0 μg/side of MK-801, 0.1 μg/side of NVP-AAM077, or 5 and 10 μg/side of Ro 25-6981. In contrast, injections of 2.5 and 5 μg/side of MK-801 or 0.5 and 1 μg/side of NVP-AAM077 impaired motor learning at Day 3 and 8. Interestingly, treatments with MK-801 and NVP-AAM077 did not alter the general motor capacities of mice as revealed by the stepping, wire suspension, and pole tests. Our study demonstrates that the NMDAR of the dorsal striatum contributes to motor learning, especially during the slow acquisition phase, and that NR2A subunits play a critical role in this process. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Analytical strategies for assessing comparability of biosimilars

Biosimilar products are required by regulatory authorities to have appropriate and comparable quality, safety and efficacy with a reference biologic product. The analytical techniques that are available to manufacturers of biosimilar medicines are well advanced and present a range of options to characterize the products and compare them with the relevant marketed reference product. This variety of analytical methods can be used to investigate the attributes of a candidate biosimilar and a reference biologic, and ensures that orthogonal methods can be deployed to characterize a single attribute, facilitating rigorous structural characterization and physicochemical evaluation. These analytical methodologies not only enable evidence for bio‐comparability to be amassed but also enable a developer of biosimilars to incorporate risk mitigation into the development strategy. This review discusses the analytical techniques available to support comparability testing, the handling of reference material and the strategic aspects to commercializing biosimilar or follow‐on biological medicinal products. Copyright © 2011 Society of Chemical Industry     

Exploring the relative impact of biological sex and masculinity–femininity values on information technology use

Previous studies in an e-commerce context suggest that there are biological differences (i.e. whether one is a man or a woman) with respect to perceptions of websites. In other research, there is evidence that psychological gender (i.e. values such as masculinity or femininity) likewise influences website perceptions. It is the aim of the current investigation to explore the possibility that both biological sex and psychological gender influence user perceptions, and to examine the predictive power of each on our model. To test these assumptions, we use an augmented technology acceptance model (TAM). To maximise variance in our sample, participants are selected from two countries that are significantly different in masculinity–femininity. As expected, psychological gender better predicted trust and TAM than biological sex. Moreover, this study validates that the masculinity–femininity dimension as originally developed by Hofstede [1980. Culture’s Consequences: International Differences in Work-Related Values. Beverly Hills, CA: Sage] can be separated into two scales – one each for masculinity and femininity. The results suggest the need for additional research into the differentiation between psychological gender and sex.