Nash equilibrium strategies in discrete-time finite-horizon dynamic games with risk-and effort-averse players

The objective of this paper is to re-examine the risk-and effort attitude in the context of strategic dynamic interactions stated as a discrete-time finite-horizon Nash game. The analysis is based on the assumption that players are endogenously risk-and effort-averse. Each player is characterized by distinct risk-and effort-aversion types that are unknown to his opponent. The goal of the game is the optimal risk-and effort-sharing between the players. It generally depends on the individual strategies adopted and, implicitly, on the the players' types or characteristics.

Motion compensation strategies in magnetic resonance imaging.

Image quality in magnetic resonance imaging (MRI) is considerably affected by motion. Therefore, motion is one of the most common sources of artifacts in contemporary cardiovascular MRI. Such artifacts in turn may easily lead to misinterpretations in the images and a subsequent loss in diagnostic quality. Hence, there is considerable research interest in strategies that help to overcome these limitations at minimal cost in time, spatial resolution, temporal resolution, and signal-to-noise ratio. This review summarizes and discusses the three principal sources of motion: the beating heart, the breathing lungs, and bulk patient movement. This is followed by a comprehensive overview of commonly used compensation strategies for these different types of motion. Finally, a summary and an outlook are provided.

Withdrawal, "serosorting" and "strategic positioning": use of risk reduction strategies with casual sex partners in men who have sex with men (MSM) in Switzerland, 2007

Introduction: 1) Withdrawal before ejaculation, "serosorting" (to choose a partner of same serostatus) and "strategic positioning" (only insertive vs. only receptive role in anal sex according to serostatus) are known to be used by MSM as alternatives to condom use. 2) Despite their questionable levels of effectiveness they are collectively labelled as "risk reduction strategies" (RRS). Objectives: The aim of this study is to estimate the prevalence and factors related to RRS in men who report unprotected anal intercourse (UAI) with occasional partners in the last 12 months. Methods: 1) In 2007, a module on RRS was included in a repeated national survey conducted among readers of gay newspapers, members of gay organizations and visitors of gay websites (N=2953). 2) Using an anonymous self-completed questionnaire, participants were asked whether, with the aim of avoiding HIV infection, RRS were used with occasional partners. Analysis: 1) Prevalences were calculated in participants who reported UAI with occasional partners in the last 12 months (n=416). 2) A logistic regression was performed, using "at least one RRS" as dependent variable. Number of partners in the last 12 months, HIV-status and usual socio-demographic characteristics were used as independent factors. Result : 1) 70% (292/416) of the participants reporting UAI used at least one RRS when they had unprotected sex with casual partners in the last 12 months (Table 1). 2) Withrawal before ejaculation was the most frequently reported strategy, followed by serosorting and strategic positioning (Table 1). 3) Participants who reported at least one RRS were more likely to be over 30 years and to belong to a gay organisation. HIV-positive and non-tested participants were less likely to report RRS than HIV-negative participants (Table 2). Conclusions: 1) The majority of MSM who reported UAI in the last 12 months tried to reduce risk of HIV transmission by using specific strategies (withdrawal, serosorting, strategic positioning). It is not known, however, to what extent the use of these strategies was systematic. 2) It is necessary to provide MSM with balanced information on these strategies and their respective level of effectiveness. 3) It is important to monitor the use of RRS in HIV behavioural surveillance surveys in MSM.

Teacher strategies to elicit knowledge from students in the CLIL classroom: the purpose of questions in controlled patterns of teacher-student interaction

This Master Dissertation comprises two parts: a personal reflection and an empirical study. The personal reflection reviews the process of professionalization undergone by its author throughout the Master. The empirical study tackles teacher strategies to elicit knowledge from students in the CLIL classroom and more specifically the purpose of questions in controlled patterns of teacher-student interaction. The theories of relevant authors such as Vigotsky, Mercer and Tsui are used as a framework to analyze the data presented. The analysis shows the different strategies to elicit knowledge used by the teacher and the appropriateness of her questions in the analyzed interaction

The Rio de Janeiro HIV Vaccine Site: I. Recruitment Strategies and Socio-demographic Data of a HIV Negative Homosexual and Bisexual Male Cohort in Rio de Janeiro, Brazil

The initial effort of the Brazilian Ministry of Health to be an active partner in the world effort in the preparation of future accurate human immune deficiency virus (HIV) efficacy trials was the establishment of a multi-centered cohort of homosexual and bisexual men. An open cohort was established to determine the HIV incidence and the socio-behavioral aspects involved in Rio de Janeiro. A total of 318 potential participants, originated from multiple sources (health units, public information, snowball recruitment), were screened and recruitment became effective through the direct involvement of target communities (with the support of Non Governmental Organizations) and the population. Among this group, seropositivity for sexually transmitted diseases was high with 23, 32 and 46% for HIV, syphilis and hepatitis B, respectively. The socio-demographic data from the first 200 participants of this HIV negative cohort suggests that the cohort volunteers are an appropriate sample of the general male population of the State of Rio de Janeiro

Attenuation of colon inflammation through activators of the retinoid X receptor (RXR)/peroxisome proliferator-activated receptor gamma (PPARgamma) heterodimer. A basis for new therapeutic strategies.

The peroxisome proliferator-activated receptor gamma (PPARgamma) is highly expressed in the colon mucosa and its activation has been reported to protect against colitis. We studied the involvement of PPARgamma and its heterodimeric partner, the retinoid X receptor (RXR) in intestinal inflammatory responses. PPARgamma(1/)- and RXRalpha(1/)- mice both displayed a significantly enhanced susceptibility to 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis compared with their wild-type littermates. A role for the RXR/PPARgamma heterodimer in the protection against colon inflammation was explored by the use of selective RXR and PPARgamma agonists. TNBS-induced colitis was significantly reduced by the administration of both PPARgamma and RXR agonists. This beneficial effect was reflected by increased survival rates, an improvement of macroscopic and histologic scores, a decrease in tumor necrosis factor alpha and interleukin 1beta mRNA levels, a diminished myeloperoxidase concentration, and reduction of nuclear factor kappaB DNA binding activity, c-Jun NH(2)-terminal kinase, and p38 activities in the colon. When coadministered, a significant synergistic effect of PPARgamma and RXR ligands was observed. In combination, these data demonstrate that activation of the RXR/PPARgamma heterodimer protects against colon inflammation and suggest that combination therapy with both RXR and PPARgamma ligands might hold promise in the clinic due to their synergistic effects.

Strategies of use of a specific immunoglobulin-rich egg yolk powder in weaning piglets

Two experiments were performed to determine the best strategy of use of the product TRACTcare® 4P (ITPSA) (TC, specific immunoglobulin-rich egg yolk powder within an energetic fatty acid matrix) in piglets from weaning and for 6 weeks, in diets without or with inclusion of antibiotics. Each trial was performed with 144 piglets in 24 pens, in a completely randomized design blocked by initial body weight. Feeds were formulated according to animal requirements in two periods. In the first trial no antibiotics were included in the feeds and no room disinfection from previous trial was performed; treatments were: 1) Negative control (NC); 2) NC+TC on top of the feed within the hopper for the first 3 days on trial (30 g/pig×day), and eventually if diarrhea appeared (TCOT); 3) NC+TC ad libitum provided in an extra hopper within the pen (TCAL); and 4) NC+TC at 5 g/kg added to the feed in the mixer (TC5). In the second trial, treatments were: 1) Positive control: basal diet that included 250 mg/kg amoxiciline (BD)+100 mg/kg colistine (AC); 2) BD+2 g/kg TC (TC2A); 3) BD+5 g/kg TC (TC5A); and 4) BD+8 g/kg TC (TC8A). In diets without antibiotics, the product TC at 5 g/kg in the feed numerically improved BW by 8% compared to Control animals, while G:F was almost identical between both groups. When antibiotics were used in the feed, replacement of colistin at 100 mg/kg for TC at 2 g/kg in feed numerically improved the performance compared to Positive control animals (for the whole trial period ADG 8% better: 390 g vs. 361 g; G:F 1% better: 0.748 kg/kg vs. 0.742 kg/kg), possibly due to the stimulation of feed consumption at weaning. In both trials, the lower number of dead and culled animals from TC5 and TC2A together with higher BW represented an advantage over Control treatments of 6% to 10% animals more and 15% to 17% total BW more at the end of the trial.

IPH response to Department of the Environment, Heritage and Local Government and the Department for Regional Development Spatial Strategies

The remit of the Institute of Public Health in Ireland (IPH) is to promote cooperation for public health between Northern Ireland and the Republic of Ireland in the areas of research and information, capacity building and policy advice. Our approach is to support Departments of Health and their agencies in both jurisdictions, and maximise the benefits of all-island cooperation to achieve practical benefits for people in Northern Ireland and the Republic of Ireland. As an all-island body, the Institute of Public Health in Ireland particularly welcomes that the Framework for Collaboration has been co-produced by the Department for Regional Development and the Department of the Environment, Heritage and Local Government. In addition the Institute of Public Health welcomes a more holistic approach to spatial planning that takes into account the environment and sustainable economic development. A clean environment and a more equitable distribution of prosperity have associated health benefits, as outlined in the IPH’s Active travel – healthy lives (2011) and Health impacts of the built environment- a review (2006).

Strategies to promote translational research within the European Organisation for Research and Treatment of Cancer (EORTC) Head and Neck Cancer Group: a report from the Translational Research Subcommittee.

Head and neck squamous cell cancer (HNSCC) is the sixth leading cause of cancer-related deaths worldwide. These tumors are commonly diagnosed at advanced stages and mortality rates remain high. Even cured patients suffer the consequences of aggressive treatment that includes surgery, chemotherapy, and radiotherapy. In the past, in clinical trials, HNSCC was considered as a single disease entity. Advances in molecular biology with the development of genomic and proteomic approaches have demonstrated distinct prognostic HNSCC patient subsets beyond those defined by traditional clinical-pathological factors such as tumor subsite and stage [Cho W (ed). An Omics Perspective on Cancer Research. New York/Berlin: Springer 2010]. Validation of these biomarkers in large prospective clinical trials is required before their clinical implementation. To promote this research, the European Organisation for Research and Treatment of Cancer (EORTC) Head and Neck Cancer Program will develop the following strategies-(i) biobanking: prospective tissue collection from uniformly treated patients in the setting of clinical trials; (ii) a group of physicians, physician-scientists, and EORTC Headquarters staff devoted to patient-oriented head and neck cancer research; (iii) a collaboration between the basic scientists of the Translational Research Division interested in head and neck cancer research and the physicians of the Head and Neck Cancer Group; and (iv) funding through the EORTC Grant Program and the Network Core Institutions Consortium. In the present report, we summarize our strategic plans to promote head and neck cancer research within the EORTC framework.

Comparison of intervention strategies for control of Triatoma dimidiata in Nicaragua

The effectiveness of three operational strategies for the control of Triatoma dimidiata was compared by a field trial in the Department of Madriz, Nicaragua. One strategy involved full pretrial evaluation, followed by spraying of all houses irrespective of whether or not they had been found to be infested. The second strategy minimised the pretrial evaluation by considering the locality infested as soon as one house was found to be positive, followed by spraying all houses. The third strategy involved full pretrial evaluation, followed by spraying only those houses found to be positive. Evaluation after twelve months indicated that all three strategies were similarly effective, since all sprayed houses remained free of infestation. However, comparative estimates of the unit intervention costs indicated that strategies 1 and 2 were substantially less efficient than the third strategy of spraying only positive houses.

Staffing strategies in SME's: determinants of external recruitment and internal promotion

The purpose of this paper is to examine the determinants of use internal or external labour market to fill a firm vacancy in SME’s taking into account the differences existing among blue and white collar jobs. Following different theories we can identify three main reasons for use internal candidates rather than external ones‐ firm specific knowledge, adverse selection problems and motivation‐. However, there are others factors that might affect this choice but the last theories don’t take into account. In this paper we try to shed some light on what are these other factors that may affect firm decision to use internal or external labour market. Particularly we analyses the relationship among new technologies, innovation activity and firm location on the staffing strategy. The results shows difference behaviour on the decision to fill a vacancy using internal or external labour markets between manufacturing and service firms, and this decision depends not only on firm internal characteristics, like technological complexity or innovation activity, but also on firm location. The results also support the hypothesis of ports of entry especially in the manufacturing sector.