Cluster Monte Carlo and numerical mean field analysis for the water liquid-liquid phase transition

Using Wolff's cluster Monte Carlo simulations and numerical minimization within a mean field approach, we study the low temperature phase diagram of water, adopting a cell model that reproduces the known properties of water in its fluid phases. Both methods allow us to study the thermodynamic behavior of water at temperatures, where other numerical approaches - both Monte Carlo and molecular dynamics - are seriously hampered by the large increase of the correlation times. The cluster algorithm also allows us to emphasize that the liquid-liquid phase transition corresponds to the percolation transition of tetrahedrally ordered water molecules.     

Milgram, stress research, and the Institutional Review Board.

Comments on a recent attempted replication of the Milgram studies (Burger, January 2009) (see record 2008-19206-001). Over the last 20 years when lecturing to undergraduates, the author found that the students consistently and vehemently denied that similar results would be obtained “today.” They would note how much more independent individuals are now, how authority is not valued to the same extent that it was in the past, and so forth. Of course in the 1960s experts said the same things. No one predicted what happened then, and he doubts that many would have predicted what Burger (2009) found now. The author's comments, with one exception, are directed toward broader issues of the research enterprise relevant to concerns touched off by Milgram and subsequent practices of institutional review boards (IRBs). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attitudinal and motivational antecedents of participation in voluntary employee development activities.

This study investigated factors influencing ongoing participation in employee development activities. A multiple-indicator structural equation model building on the theory of planned behavior and prior employee development literature was tested with a survey across 4 organizations on 2 occasions. The model uses reactions to past participation and past supportiveness of the social and organizational environment as indirect antecedents of participation, filtered through their impact on attitudes and behavioral intentions toward future participation. Learning goal orientation also influenced attitudes toward participation. Whereas personal control over participation and higher levels of voluntariness were negatively related to participation, intentions to participate and availability of opportunities arose as strong predictors of higher participation rates. Many significant hypothesized paths were found, and 85% of the variance in participation was explained by the model variables. Increasing employee awareness of opportunities and managing positive attitudes toward those opportunities are recommended as key factors for increasing participation rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

让入门级图形制作告别消费级平台 惠普Z400工作站电脑

在我们以往的认知中,工作站电脑往往应用在电影渲染、矿产勘探、汽车设计等需要高性能计算机的行业,其价格也高高在上。其实工作站电脑当中也有定位于中小企业、甚至个人用户的入门级产品,我们本期要为大家介绍的惠普Z400就是其中代表。     

Stakeholder engagement in water governance as social learning: lessons from practice

ABSTRACT

The OECD Principles on Water Governance set out various requirements for stakeholder engagement. Coupled with conceptualizations of social learning, this article asks how we define and enact stakeholder engagement and explores the actual practice of engagement of stakeholders in three fields of water governance. The results suggest that a key consideration is the purpose of the stakeholder engagement, requiring consideration of its ethics, process, roles and expected outcomes. While facilitators cannot be held accountable if stakeholder engagement ‘fails’ in terms of social learning, they are responsible for ensuring that the enabling conditions for social learning are met.     

Measurement of asphaltene agglomeration from cold lake bitumen diluted with n-alkanes

A laser particle analyzer was used to study the formation of asphaltene agglomerates from Cold Lake bitumen due to the introduction of paraffinic diluents. The growth of the particles over time was investigated, and it was found that asphaltene particle growth is essentially an instantaneous process; that is, the final agglomerate size is reached within 5 seconds. The type of diluent used to precipitate the asphaltenes was determined to have a major effect on the size distribution of asphaltene agglomerates. The average particle size of asphaltene agglomerates ranged from 169 ptn for n-hexadecane to 299m for n-pentane. A relationship is shown to exist between the average particle size of asphaltene agglomerates and the carbon number of the diluent used.