Impact of combination therapies on HIV risk perceptions and sexual risk among HIV-positive and HIV-negative gay and bisexual men.

The availability of improved HIV treatments may prompt reduced concern about HIV and sexual risk. Gay and bisexual men (N?=?554, 17% HIV-positive) completed measures of treatment attitudes, sexual risk, and assumptions regarding the infectiousness of sexual partners. A substantial minority reported reduced HIV concern related to treatment advances. Reduced HIV concern was an independent predictor of sexual risk, particularly among HIV-positive men. In response to hypothetical scenarios describing sex with an HIV-positive partner, participants rated the risk of unprotected sex to be lower if the partner was taking combination treatments and had an undetectable viral load, relative to scenarios with a seropositive partner not taking combination treatments. Prevention efforts must address attitudinal shifts prompted by recent treatment successes, stressing the continued importance of safer sex, and that an undetectable viral load does not eliminate infection risks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use it or lose it: Engaged lifestyle as a buffer of cognitive decline in aging?

Data from the Victoria Longitudinal Study were used to examine the hypothesis that maintaining intellectual engagement through participation in everyday activities buffers individuals against cognitive decline in later life. The sample consisted of 250 middle-aged and older adults tested 3 times over 6 years. Structural equation modeling techniques were used to examine the relationships among changes in lifestyle variables and an array of cognitive variables. There was a relationship between changes in intellectually related activities and changes in cognitive functioning. These results are consistent with the hypothesis that intellectually engaging activities serve to buffer individuals against decline. However, an alternative model suggested the findings were also consistent with the hypothesis that high-ability individuals lead intellectually active lives until cognitive decline in old age limits their activities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vibrational thermodynamics of materials

The literature on vibrational thermodynamics of materials is reviewed. The emphasis is on metals and alloys, especially on the progress over the last decade in understanding differences in the vibrational entropy of different alloy phases and phase transformations. Some results on carbides, nitrides, oxides, hydrides and lithium-storage materials are also covered.Principles of harmonic phonons in alloys are organized into thermodynamic models for unmixing and ordering transformations on an Ising lattice, and extended for non-harmonic potentials. Owing to the high accuracy required for the phonon frequencies, quantitative predictions of vibrational entropy with analytical models prove elusive. Accurate tools for such calculations or measurements were challenging for many years, but are more accessible today. Ab initio methods for calculating phonons in solids are summarized. The experimental techniques of calorimetry, inelastic neutron scattering, and inelastic X-ray scattering are explained with enough detail to show the issues of using these methods for investigations of vibrational thermodynamics. The explanations extend to methods of data analysis that affect the accuracy of thermodynamic information.It is sometimes possible to identify the structural and chemical origins of the differences in vibrational entropy of materials, and the number of these assessments is growing. There has been considerable progress in our understanding of the vibrational entropy of mixing in solid solutions, compound formation from pure elements, chemical unmixing of alloys, order-disorder transformations, and martensitic transformations. Systematic trends are available for some of these phase transformations, although more examples are needed, and many results are less reliable at high temperatures. Nanostructures in materials can alter sufficiently the vibrational dynamics to affect thermodynamic stability. Internal stresses in polycrystals of anisotropic materials also contribute to the heat capacity. Lanthanides and actinides show a complex interplay of vibrational, electronic, and magnetic entropy, even at low temperatures.A “quasiharmonic model” is often used to extend the systematics of harmonic phonons to high temperatures by accounting for the effects of thermal expansion against a bulk modulus. Non-harmonic effects beyond the quasiharmonic approximation originate from the interactions of thermally-excited phonons with other phonons, or with the interactions of phonons with electronic excitations. In the classical high temperature limit, the adiabatic electron-phonon coupling can have a surprisingly large effect in metals when temperature causes significant changes in the electron density near the Fermi level. There are useful similarities in how temperature, pressure, and composition alter the conduction electron screening and the interatomic force constants. Phonon-phonon “anharmonic” interactions arise from those non-harmonic parts of the interatomic potential that cannot be accounted for by the quasiharmonic model. Anharmonic shifts in phonon frequency with temperature can be substantial, but trends are not well understood. Anharmonic phonon damping does show systematic trends, however, at least for fcc metals.Trends of vibrational entropy are often justified with atomic properties such as atomic size, electronegativity, electron-to-atom ratio, and mass. Since vibrational entropy originates at the level of electrons in solids, such rules of thumb prove no better than similar rules devised for trends in bonding and structure, and tend to be worse. Fortunately, the required tools for accurate experimental investigations of vibrational entropy have improved dramatically over the past few years, and the required ab initio methods have become more accessible. Steady progress is expected for understanding the phenomena reviewed here, as investigations are performed with the new tools of experiment and theory, sometimes in integrated ways.     

Virtual Human versus Human Administration of Photographic Lineups

One solution to mistaken identification by a crime's victims and eyewitnesses is to use a virtual officer to conduct identification procedures. Results from a study comparing a virtual officer with a live human investigator indicate that the virtual officer performs comparably to the human in terms of identification accuracy, emotional affect, and ease of use.     

Stephen A. Mitchell (1946–2000).

Memorializes Stephen A. Mitchell, a teacher, administrator and practitioner in psychoanalysis and psychotherapy. Mitchell was a leading proponent of an integrative, relational perspective in psychoanalysis. Mitchell was sympathetic to the plight of psychologists and others excluded from established organizations, and he helped them to establish their own innovative training programs not only in the US but also abroad (e.g., Canada and Israel). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Systems analyses and the sustainable transfer of renewable energy technologies: A focus on remote areas of Africa

Sustainable energy provision is regarded as one of the most significant challenges facing the realm of development, especially in Africa where large proportions of the population still lack access to energy services. Although there have been much efforts to address these problems with renewable energy technologies, there have also been substantial failures and problems. The Intermediate Technology Development Group (ITDG) has developed a manual that seeks to address these implementation issues. The Renewable Energy for Sustainable Rural Livelihoods workgroup has also developed such a framework, termed SURE, which is a multi-criteria decision analysis modelling tool. Both of these frameworks rely heavily on the Sustainable Livelihoods Approach and emphasise the need to rigorously analyse the sub-systems where technologies are to be introduced. These two frameworks have been integrated and assessed in terms of their applicability for the South African rural renewable energy landscape through a Delphi study conducted with several experts in the energy sector. The results indicate that the integrated framework is suitable for the South African context, with additions to the ITDG and SURE frameworks suggested. Finally the paper highlights a potential concern in the South African renewable energy industry in that technology assessment methods that are utilised in practise do not incorporate the concepts of sustainability science adequately; this must be addressed through further case study research efforts.     

The perils of eclecticism as therapeutic orientation.

This current article discusses the "perils of eclecticism as therapeutic orientation". Although some who label themselves "eclectic" recognize the importance of a well-articulated theory in their work, the vast majority attempt to avoid theorizing. Their main fear appears to be that a theoretical system will bias their interpretations of clinical or empirical data and thus leave them inflexible and closed-minded. The present author appreciates the possibility of theoretical speculations becoming unmonitored biases, but eclectics must also appreciate that biases cannot be avoided, only the lack of monitoring can be avoided. In fact, to delude oneself into thinking that one has avoided biases is to guarantee that one is operating from an unmonitored bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

为孩子们工作

<正>在不影响紧邻的旧医院运行的前提下建造墨尔本皇家儿童医院,对工地上的8台塔式起重机是一个特殊的挑战。     

Root-metaphors for understanding: A framework for teachers and teacher educators of information and communication technologies

This paper argues for understanding ICT from the standpoint of philosophical world views. We present a framework, based on Pepper’s root-metaphors (Formism, Contextualism, Mechanism, Organicism, and Animism/Mysticism) and we illustrate the use of the framework by looking at a common example of ICT: e-mail. It is argued that such a framework is potentially helpful to ICT teachers, especially when they work with pre-service education students who are struggling with how to integrate ICT critically into their future classrooms.