Epigenetic status of human embryonic stem cells

We examined the allele-specific expression of six imprinted genes and the methylation profiles of three imprinting control regions to assess the epigenetic status of human embryonic stem cells. We identified generally monoallelic gene expression and normal methylation patterns. During prolonged passage, one cell line became biallelic with respect to H19, but without loss of the gametic methylation imprint. These data argue for a substantial degree of epigenetic stability in human embryonic stem cells.     

In vitro inhibition of tRNA methyltransferases by queen substance, a pheromone of queen honeybees]

The Queen Substance 1, a pheromone of the queen Honeybee Apis mellifica is an in vitro inhibitor of E. coli B tRNA methylations. This activity is not specific of the methylase source, as inhibitions have been observed with preparations from queen honeybee ovaries, Rat liver or a Mouse plasmocytoma 1-adenine methylase. These results, together with preceding ones concerning t, t-farnesyl-acetone 3, are discussed.     

Biosynthesis of deuteriated amino acids byCandida lipolytica

Summary Biosynthesis of a whole series of deuteriated amino acids has been carried out, by cultivation of the yeastCandida lipolytica in an artificial medium composed of a deuterio-alkane, heavy water, water and some mineral salts.Acknowledgments. This work has been carried out with the aid of grants from The Swedish Medical Research Council. Thanks are due to Mr Nils Engström for his skilful technical assistance during the yeast growth, and to Mrs Monica Olsson for the Moore-Stein analysis.     

氯接触池中溶质输移与消毒过程的数值模拟

为使饮用水处理中氯接触池达到较高的掺混和消毒效率 ,提出一种数学模拟方法。采用二维水流动量方程和连续方程、自由氯的反应过程一阶动力学方程和细菌数量衰减过程的 Chick- Watson公式等组成的模型 ,计算了氯接触池中溶质输移与消毒过程。对 3种涡粘性湍流模型与 3种差分格式的不同组合下计算所得到的多组模拟结果进行了分析 ,并与试验数据进行了比较。研究表明 :通过数值方法对池内的水流紊动结构及自由氯输运、反应和细菌生灭等过程进行计算模拟 ,与仅依据不同设计方案所得滞留曲线进行评价的做法相比 ,更有利于比较内部细节的设计 ,方便地判定不同设计方案的运行效率     

When Research and Practice Collide: The Role of Action Research When There Is a Conflict of Interest with Stakeholders

This article discusses problematic aspects of the role of the action researcher when working with multiple stakeholders on a complex research project concerning regional development. The case presented here deals with the improvement of the regional innovation system in a small region in the south of Norway. The project resulted in a conflict between stakeholders and the action research (AR) team. We claim that when working in a regional context, the role of the action researcher is set to be a collaborator in a context of power play; the ultimate stakeholders must be defined as the citizens in that region. Therefore, in some situations the action researcher must have a legitimatised right to abandon collaboration and present a critical voice in the public deliberation. Strategic power play and strategic action by stakeholders represent a clear threat to the soft approach of collaboration, reflectivity, and democratic dialogue that AR represents. The ultimate challenge and obligation of the action researcher is to improve democracy in society in a long-term perspective through representing a critical capacity in the public deliberation.