Three-dimensional instabilities and transition of steady and pulsatile axisymmetric stenotic flows

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Foreign national prisoners in the UK: explanations and implications

This article examines the rapid expansion of the foreign national prison population in the UK against a backdrop of public and political anxiety about immigration and crime. It explores official data considering some of the possible explanations for the growth in the number of foreign national prisoners and the implications this has for penal management. Whilst increases in both the number of foreign nationals entering the UK and the number of foreign nationals in UK prisons has strengthened the association between immigration and crime in the public imagination, there is little empirical evidence to suggest that foreign nationals are more dangerous than British nationals. Instead, the growth of the foreign national prison population appears to stem from a number of sources that may operate alone or in tandem

pH regulatory Na/H exchange by Amphiuma red blood cells.

In Amphiuma red blood cells, the Na/H exchanger has been shown to play a central role in the regulation of cell volume following cell shrinkage (Cala, P. M. 1980. Journal of General Physiology. 76:683-708.) The present study was designed to evaluate the existence of pH regulatory Na/H exchange in the Amphiuma red blood cell. The data illustrate that when the intracellular pHi was decreased below the normal value of 7.00, Na/H exchange was activated in proportion to the degree of acidification. Once activated, net Na/H exchange flux persisted until normal intracellular pH (6.9-7.0) was restored, with a half time of approximately 5 min. These observations established a pHi set point of 7.00 for the pH-activated Na/H exchange of Amphiuma red blood cell. This is in contrast to the behavior of osmotically shrunken Amphiuma red blood cells in which no pHi set point could be demonstrated. That is, when activated by cell shrinkage the Na/H exchange mediated net Na flux persisted until normal volume was restored regardless of pHi. In contrast, when activated by cell acidification, the Na/H exchanger functioned until pHi was restored to normal and cell volume appeared to have no effect on pH-activated Na/H exchange. Studies evaluating the kinetic and inferentially, the molecular equivalence of the volume and pHi-induced Amphiuma erythrocyte Na/H exchanger(s), indicated that the apparent Na affinity of the pH activated cells is four times greater than that of shrunken cells. The apparent Vmax is also higher (two times) in the pH activated cells, suggesting the involvement of two distinct populations of the transporter in pH and volume regulation. However, when analyzed in terms of a bisubstrate model, the same data are consistent with the conclusion that both pH and volume regulatory functions are mediated by the same transport protein. Taken together, these data support the conclusion that volume and pH are regulated by the same effector (Na/H exchanger) under the control of as yet unidentified, distinct and cross inhibitory volume and pH sensing mechanisms

Motivating masters

Motivation is the powerful inner force that drives all of our thoughts, feelings and actions. One of the critical differences between a champion athlete and an also-ran entails how they are able to maintain intensity of effort over time. Elite athletes such as 45-year-old sprinter Merlene Ottey, who competed in her 7th Olympics in Athens 2004, have the propensity to direct their energies extremely effectively. We will be examining how motivation contributes to success for masters athletes and suggest some motivational techniques which you can tailor to your athletes’ needs

Internet addiction and loneliness among children and adolescents in the education setting: an empirical pilot study

Research into various behavioural addictions has shown that such behaviour can negatively impact psychological wellbeing. One behavioural addiction that has been increasingly studied empirically is that of Internet Addiction (IA). Despite general consensus concerning the negative effects of IA on mental health and other indices of physical and psychosocial health, little research has been done in child and adolescent populations in specific contexts. The main objectives of this study were to (i) investigate the extent of problems caused by IA in children and adolescents, (ii) determine the socio-demographic and behavioural characteristics of children and adolescents with IA, and (iii) to provide a model capable of predicting IA in the educational context among the target population. A total of 131 Portuguese school children and adolescents participated in this study. Results indicated a relatively high incidence of IA in the sample (13%). Additionally, the correlational analyses revealed associations between IA and loneliness, social loneliness, and other variables related to the educational context. Results demonstrated that IA could be predicted using a model encompassing three variables (i.e., weekly Internet usage, loneliness, and classroom behaviour). Overall, the present findings corroborated results from other studies and added to the behavioural addiction literature by examining a younger cohort than previous empirical studies

Photoactive thin silver films by atmospheric pressure CVD

We report the visible and UV activity of thin silver films. The films are grown using a CVD process employing aqueous-based silver precursors, flame-assisted chemical vapour deposition. This approach overcomes many of the previously encountered limitations to silver deposition by employing an atmospheric pressure process, low-cost and low-toxicity precursors. The resultant films are assessed for activity using stearic acid destruction as a model compound. We also report on the addition of titania to these silver films to increase the potential functionality. This activity is also demonstrated, where the films appear largely transparent to the eye, further widening the potential application of this work. It is speculated that the nanoparticulate nature, of the CVD silver, is crucial in determining photoactivity

Spatial Pillage Game

A pillage game is a coalitional game as a model of Hobbesian anarchy. The spatial pillage game introduces a spatial feature into the pillage game. Players are located in regions and can travel from one region to another. The players can form a coalition and combine their power only within their destination regions, which limits the exertion of the power of each coalition. Under this spatial restriction, a coalition can pillage less powerful coalitions without any cost. The feasibility of pillages between coalitions determines the dominance relation that defines stable states in which powers among the players are endogenously balanced. With the spatial restriction, the set of stable states changes. However, if the players have forecasting ability, then the set of stable states does not change with the spatial restriction. Core, stable set, and farsighted core are adopted as alternative solution concepts.allocation by force, coalitional games, pillage game, spatial restriction, stable set, farsighted core