大肠杆菌同义密码子重复序列中密码子的使用

以大肠杆菌基因组为样本,研究同义密码子重复序列与ORF全序列中各密码子相对使用频率的差异,分析同义密码子重复序列中密码子重复的偏好.结果表明部分密码子的使用与ORF全序列中的使用不同,并非所有密码子的使用与基因表达水平正相关;同义密码子重复序列中密码子重复具有偏好性,部分密码子重复在四联体中有位置偏好.同义密码子重复的最大长度与所编码的氨基酸亲疏水性质、简并度及构成密码子的碱基性质有关.     

作为方法论的经验主义——论维特根斯坦后期哲学反形而上学主张

维特根斯坦后期要贯彻的经验主义的原则是指:我们在语言活动中,借助于哲学上的全面综观态度,意识到语词的每一次使用的独特经验积累,以及这一次使用所具有用法的自明性。维特根斯坦后期比前期的经验主义较彻底,克服了前期的形而上学思想,由此提出其语言哲学的基本任务。     

Alternative Time Scales and Failure Time Models

In many reliability applications, there may not be a unique plausible scale in which to measure time to failure or assess performance. This is especially the case when several measures of usage are available on each unit. For example, the age, the total number of flight hours, and the number of landings are usage measures that are often considered important in aircraft reliability. Similarly, in medical or biological applications of survival analysis there are often alternative scales (e.g., Oakes, 1995). This paper considers the definition of a "good" time scale, along with methods of determining a time scale.     

贵阳方言的"下"xa13

汉语方言中,西部地区(包括西北和西南地区)方言中的"下",读音和语义有区别于其他汉语北方方言的共同特点.而在西南官话中,"下"更具有较高的一致性.本文描述分析贵阳方言的"下",具有西南官话一致性的同时,在词汇和语法意义方面有其自身特色.     

“者”字形义探微

“者”的本义历来众说纷纭,本文认为“者”当表“附著”义,并对“者”的演嬗和用法进行了探讨。     

简评《韦氏新世界美语词典》(第三版)

韦氏家族的新成员《韦氏新世界美语词典》(第三版 )是一部颇具特色的中型词典。它充分继承和发扬了韦氏词典的两大传统特色 ,即再现丰富的词源信息和标识美国用词 ,同时它在形式和内容方面还有一些新的特色 ,读者能够更加有效地使用该词典     

Using Cost Per Use to Assess Big Deals

This presentation from the 23rd North Carolina Serials Conference discussed the Carolina Consortium's recent consortium-wide analysis of its big deal ejournal packages, with cost per use as the primary metric. This session addressed the pros and cons of cost-per-use (CPU) data and considered how consortia and individual schools should best utilize the data. Bernhardt discussed how the Carolina Consortium gathered and analyzed CPU data and the impact the examination had on determining whether individual schools cancelled, renewed, or joined big deals. Seven schools were identified as having big deals with CPU higher than desired. Of those seven, four schools chose to renew their deals, while three chose to cancel. Bucknall determined that while CPU is an important metric to analyze in making renewal and cancellation decisions, it is not the only factor.     

Toward an Effective Design of Behavioral Health Care Delivery: An Empirical Analysis of Care for Depression

A criticism of behavioral health care delivery is that it has largely missed the social determinants of behavioral health disorders and their diagnosis. Toward addressing this criticism, this study evaluates the delivery of behavioral health care as a part of primary care operations. Focusing on the treatment of depression, the study results show that: (i) primary care clinics operating in communities with superior social environment characteristics are associated with improved depression outcomes in the short term, and (ii) psychosocial resources (social and emotional support) and the built environment (man‐made resources and infrastructure to support human activity) of primary care clinics are associated with sustaining the improvement in depression outcome in the long term. Centering our attention on IT‐enabled, evidence‐based, and affordable primary care as mechanisms that can enable the integration of behavioral and medical care delivery, the results suggest that IT‐enabled and evidence‐based primary care are associated with improvements in depression outcomes. We also find that the effect of improving the affordability of behavioral health care delivery depends on the community's socioeconomic status. Primary care clinics in socioeconomically disadvantaged communities practicing cost‐containment are associated with improvements in depression outcomes, and, therefore, can contribute toward reducing disparities in behavioral health care delivery. Counter to our original expectations, we find that the effect of evidence‐based care on improvements on depression outcomes increases as the availability of medically trained behavioral health care specialists practicing in a community increases lending support to concerns that primary care clinics in resource‐rich communities obtain greater benefit from quality improvement interventions.     

Incentive for Peer‐to‐Peer Knowledge Sharing among Farmers in Developing Economies

This study examines the peer‐to‐Peer interactions among farmers when both knowledge learning and sharing are available. We construct a stylized model in which heterogeneous farmers are endowed with their initial production capabilities and can post questions in the platform for help. A representative expert regularly monitors the forum and provides answers to the farmers’ questions, but may be non‐responsive sometimes due to the limited capacity. A knowledgeable core user (farmer) can choose to be silent or responsive, and is allowed to strategically determine the informativeness of her answers. The farmers face the minimum quantity restriction for attracting the buyers, and must make production before the time of sales. We show that in equilibrium the core user never provides answers that are more informative than the expert's, irrespective of her ex ante knowledge level. Redesigning or restructuring the platform does not help eliminate this inefficient knowledge provision. We also find that hiring more staff to frequently monitor the forum turns out to be detrimental for the peer‐to‐peer interactions. Moreover, the competition on knowledge sharing between the platform expert and the core user features strategic complementarity sometimes but strategic substitution at other times. Third, charging for the platform usage may discourage uninformative answers, but it could also discourage the core user from sharing knowledge with other farmers.     

古代汉语中"为动用法"与使动、意动用法的区别

古代汉语的"为动"与使动、意动用法有质的不同.为动句是用"主·谓·宾"结构("S+V+M")表示了"S+为+M+V"式表示的语文关系的内容,二者是同义句式,可以共时变换;在古代汉语中"主·谓·宾"结构具有多义性;使动、意动用法的句子中主、谓、宾之间的语义关系与为动句不同;使动、意动与为动同义变换的句式结构不同.