Molecular characterisation of oxymethylene-linked poly(oxyethylene)

Tetraethylene glycol (TEG) or polyethylene glycol 200 (PEG200) was reacted with CH₂Br₂ in a modified Williamson synthesis to form oxymethylene-linked chains. Analytical and preparative gel permeation chromatography plus nuclear magnetic resonance spectroscopy were used to show that the product of reaction consisted of rings with degree of condensation n = 1?15 or more (i.e. 14 to 210 or more atoms in the rings formed from TEG) and chains with molecular weights up to 10⁶ and a wide molecular weight distribution.     

Perceived attitudes of schizophrenic inpatients in relation to rehospitalization.

Forty-nine schizophrenic inpatients who were ready for discharge completed the Influential Relationships Questionnaire. This instrument measures respondents' perceptions of three characteristic attitudes (care, overprotection, and criticism) demonstrated by two influential people in the patients' lives. The subjects were followed up for a 9-month period. Readmitted patients (N?=?21) rated the second-most-influential person higher on the Overprotection and Criticism scales and lower on the Care scale than did nonreadmitted patients (N?=?28). The implications of these findings in relation to rehospitalization are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

孟买和墨尔本：与交通可持续发展背道而驰

在大多数国家中，交通行业已成为目前温室气体排放增长最迅猛的来源。本文着眼于交通可持续发展和生态现代化问题，分析了孟买和墨尔本这两个城市在交通可持续发展与交通规划实践之间的矛盾，从而得出这样的结论：在自由化和竞争经济环境下的国家和城市之中，严重低估了在生态现代化实践中障碍和矛盾。     

Displacement Accuracy of Discontinuous Deformation Analysis Method Applied to Sliding Block

Discontinuous deformation analysis (DDA) is a discrete element method that was developed for computing large deformation in fractured rock masses. In this paper, we present an alternative derivation of the basic theory of DDA for planar (two-dimensional) problems, and we address the accuracy of the DDA method for sliding blocks using sensitivity analyses. Results of analyses with different parameters show that the residual and relative errors in the displacement of a frictional sliding block are controlled by the perturbation in the initial time steps of the simulation. In addition, we expose a systematic error induced by the DDA penalty formulation. Overall, the initial perturbation of the solution decreases with decreasing friction angle and increasing contact penalty and, counterintuitively, decreases with increasing time step size. All analyses show that the long runout behavior of the system trends toward the analytic solution, independent of the initial perturbation. The resulting precision of the long runout simulation is more than sufficient for all problems of engineering interest.     

On the Nature of Interaction Between Fullerene and Aniline

Interaction between fullerene C₆₀ and N,N-dialkyl-substituted anilines was studied by gas-liquid chromatography (GLC) and titration calorimetry. The GLC study was performed at 140-200°C in the poly(tetramethylbenzene) solvent with ultra-high solubility of C₆₀. No interaction of the C₆₀-aniline type was registered under such conditions. Calorimetric titration performed at 25°C in a non-aromatic solvent confirmed the lack of complex formation. Minute exoeffect registered is explained by suppressing of the rotation motion of the C₆₀ molecules accompanied by energy dissipation for the aniline environment.     

A Tribological Model for Chocolate in the Mouth: General Implications for Slurry-Lubricated Hard/Soft Sliding Counterfaces

We have investigated the rheological and lubrication properties of molten chocolate samples. To this end, a series of chocolate samples having various textural/compositional features have been prepared. The rheological properties of the chocolate samples are discussed in terms of the Casson model. The lubrication properties of the molten chocolate samples have been characterized by means of pin-on-disk tribometry. For the tribo-pairs, zirconia (ZrO₂) and poly(tetrafluoroethylene) (PTFE) have been used in all permutations for both slider (pin) and track (disk), providing the four tribo-pair combinations; ZrO₂/ZrO₂, PTFE/ZrO₂, ZrO₂/PTFE, and PTFE/PTFE. The results showed that both the rheological and lubrication properties of the chocolate samples are strongly influenced by the textural and compositional characteristics. The lubrication properties are further influenced by the choice of the tribo-pair. The different lubrication properties of the chocolate samples at different tribo-pairs are discussed in terms of particle behavior in the surrounding region of the inlet of the sliding tribo-pairs.     

The Dynamic Selection of Coordination Mechanisms

This paper presents and evaluates a decision making framework that enables autonomous agents to dynamically select the mechanism they employ in order to coordinate their inter-related activities. Adopting this framework means coordination mechanisms move from the realm of something that is imposed upon the system at design time, to something that the agents select at run-time in order to fit their prevailing circumstances and their current coordination needs. Using this framework, agents make informed choices about when and how to coordinate and when to respond to requests for coordination. The framework is empirically evaluated, in a grid world scenario, and we highlight those types of environments in which it is effective.     

Personality and the genetic risk for alcohol dependence.

The extent to which the genetic risk for alcohol dependence (AD) and conduct disorder (CD) and their common genetic risk overlap with genetic factors contributing to variation in dimensions of personality was examined in a study of 6,453 individuals from 3,383 adult male and female same-sex and unlike-sex twin pairs from the Australian Twin Registry. The associations between the personality dimensions of positive emotionality, negative emotionality, and AD and CD risk were modest, whereas the associations between behavioral undercontrol and AD and CD risk were substantially higher. Genetic influences contributing to variation in behavioral undercontrol accounted for about 40% of the genetic variation in AD and CD risk and about 90% of the common genetic risk for AD and CD. These results suggest that genetic factors contributing to variation in dimensions of personality, particularly behavioral undercontrol, account for a substantial proportion of the genetic diathesis for AD and most of the common genetic diathesis for AD and CD among both men and women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)