Mechanism of attenuation of angiotensin-II-induced protein degradation by insulin-like growth factor-I (IGF-I)

Insulin-like growth factor-I (IGF-I) has been shown to attenuate protein degradation in murine myotubes induced by angiotensin II through downregulation of the ubiquitin-proteasome pathway, although the mechanism is not known. Angiotensin II is known to upregulate this pathway through a cellular signalling mechanism involving release of arachidonic acid, activation of protein kinase Cα (PKCα), degradation of inhibitor-κB (I-κB) and nuclear migration of nuclear factor-κB (NF-κB), and all of these events were attenuated by IGF-I (13.2 nM). Induction of the ubiquitin-proteasome pathway has been linked to activation of the RNA-activated protein kinase (PKR), since an inhibitor of PKR attenuated proteasome expression and activity in response to angiotensin II and prevented the decrease in the myofibrillar protein myosin. Angiotensin II induced phosphorylation of PKR and of the eukaryotic initiation factor-2 (eIF2) on the α-subunit, and this was attenuated by IGF-I, by induction of the expression of protein phosphatase 1, which dephosphorylates PKR. Release of arachidonic acid and activation of PKCα by angiotensin II were attenuated by an inhibitor of PKR and IGF-I, and the effect was reversed by Salubrinal (15 μM), an inhibitor of eIF2α dephosphorylation, as was activation of PKCα. In addition myotubes transfected with a dominant-negative PKR (PKRΔ6) showed no release of arachidonate in response to Ang II, and no activation of PKCα. These results suggest that phosphorylation of PKR by angiotensin II was responsible for the activation of the PLA2/PKC pathway leading to activation of NF-κB and that IGF-I attenuates protein degradation due to an inhibitory effect on activation of PKR. © 2007 Elsevier Inc. All rights reserved.

Diseño de un plan estratégico de mercadotecnia para generar demanda en los productos y servicios que ofrece el mercado municipal de San Nicolás Lempa del municipio de Tecoluca, departamento de San Vicente.

Debido a que los objetivos con que fue ejecutado el proyecto del Mercado Municipal de San Nicolás Lempa no ha sido alcanzado, surge la necesidad de realizar una investigación orientada a identificar los factores que los han limitado. El problema fundamental son las bajas ventas que han obtenido los comerciantes desde su apertura, por lo que el grupo investigador ha diseñado un Plan Estratégico de Mercadotecnia con el cual se genere demanda en los productos y servicios que ofrece el mercado. Para recolectar la información que fue necesaria para el diseño del plan se utilizó el método científico y específicamente el deductivo (que parte de lo general a lo específico), la investigación realizada estuvo encaminada a obtener información objetiva y real de la situación actual. Las técnicas utilizadas para recopilar los datos fueron: La entrevista realizada a la Administradora del mercado y cuestionarios dirigidos a cada uno de los comerciantes que forman parte de la muestra del Mercado Municipal de San Nicolás Lempa. Además, para realizar la investigación de campo, también se hizo uso de cuestionarios dirigidos a los consumidores y a la competencia, así como la observación directa. Una vez recolectados los datos, tabulados y analizados se determinó que el principal factor que limita la afluencia de consumidores en el mercado se debe a la falta de transporte hacia dicho lugar y que no se ofrecen todos los productos que llenen sus expectativas y satisfagan sus necesidades, por lo que los comerciantes poseen incertidumbre, lo que les genera temor a invertir sus recursos en más productos. Por otra parte, el mercado no posee una filosofía enfocada a los consumidores, productos y necesidades que desea satisfacer y que a la vez sirva de lineamientos y orientación para cada una de las personas involucradas en el mismo. En cuanto a la competencia se observa que la ubicación es más estratégica y poseen precios semejantes a los del mercado. Una vez teniendo los resultados que la investigación requiere se procede al diseño del Plan Estratégico de Mercadotecnia en el cual se hace una propuesta de las estrategias que deben realizarse a corto y largo plazo, la mezcla de mercadotecnia, una misión y visión y la estructura organizativa adecuada para que cada una de las personas tenga claro cuáles son sus funciones así como saber a quién acudir en cualquier situación que se presente; finalmente, se hace alusión a la implementación, evaluación y control del plan.

Employing the five-factor mentoring instrument : analysing mentoring practices for teaching primary science.

Primary science education is a concern around the world and quality mentoring within schools can develop preservice teachers’ practices. A five-factor model for mentoring has been identified, namely, personal attributes, system requirements, pedagogical knowledge, modelling, and feedback. Final-year preservice teachers (mentees, n=211) from three Turkish universities were administered a previously validated instrument to gather perceptions of their mentoring in primary science teaching. ANOVA indicated that each of these five factors was statistically significant (p<.001) with mean scale scores ranging from 3.36 to 4.12. Although mentees perceived their mentors to provide evaluation feedback (95%), model classroom management (88%), guide their preparation (96%), and outline the science curriculum (92%), the majority of mentors were perceived not to assist their mentees in 10 of the 34 survey items. Professional development programmes that target the specific needs of these mentors may further enhance mentoring practices for advancing primary science teaching.

Combination strategies for a factor analysis phone-conditioned speaker verification system

This work aims to take advantage of recent developments in joint factor analysis (JFA) in the context of a phonetically conditioned GMM speaker verification system. Previous work has shown performance advantages through phonetic conditioning, but this has not been shown to date with the JFA framework. Our focus is particularly on strategies for combining the phone-conditioned systems. We show that the classic fusion of the scores is suboptimal when using multiple GMM systems. We investigate several combination strategies in the model space, and demonstrate improvement over score-level combination as well as over a non-phonetic baseline system. This work was conducted during the 2008 CLSP Workshop at Johns Hopkins University.

Confirmatory factor analysis of the Way of Coping Checklist-Revised (WCCL-R) in the Asian context

Industrial employment growth has been one of the most dynamic areas of expansion in Asia; however, current trends in industrialised working environments have resulted in greater employee stress. Despite research showing that cultural values affect the way people cope with stress, there is a dearth of psychometrically established tools for use in non-Western countries to measure these constructs. Studies of the "Way of Coping Checklist-Revised" (WCCL-R) in the West suggest that the WCCL-R has good psychometric properties, but its applicability in the East is still understudied. A confirmatory factor analysis (CFA) is used to validate the WCCL-R constructs in an Asian population. This study used 1,314 participants from Indonesia, Sri Lanka, Singapore, and Thailand. An initial exploratory factor analysis revealed that original structures were not confirmed; however, a subsequent EFA and CFA showed that a 38-item, five-factor structure model was confirmed. The revised WCCL-R in the Asian sample was also found to have good reliability and sound construct and concurrent validity. The 38-item structure of the WCCL-R has considerable potential in future occupational stress-related research in Asian countries.