22 research outputs found
Self-Etching-Induced Morphological Evolution of ZnO Microrods Grown on FTO Glass by Hydrothermal Method
The evolution of postpollination reproductive isolation in Costus
Reproductive isolation is critical to the diversification of species. Postpollination barriers may be important in limiting gene flow between closely related species, but they are relatively cryptic and their evolution is poorly understood. Here, we review the role of postpollination reproductive isolation in plants, including the various stages at which it operates and the hypotheses for how it may evolve. We then review empirical studies in the plant genus Costus, evaluating documented postpollination barriers in light of these hypotheses. We summarize isolation due to parental style length differences and present evidence supporting the hypothesis that the differences are in part a by-product of selection on floral morphology. Additionally, we show that reduced pollen adhesion, germination, and tube growth contribute to reproductive isolation between two closely related sympatric species of Costus. Geographic variation in the strength of these crossing barriers supports the hypothesis that they evolved under reinforcement, or direct natural selection to strengthen isolation
JNK/AP-1 activation contributes to tetrandrine resistance in T-cell acute lymphoblastic leukaemia
Polythiophene derivatives functionalized with maleimide moiety as pendant for bulk heterojunction photovoltaic cells
Medical studentsâ perceptions and attitudes about family practice: a qualitative research synthesis
<p>Abstract</p> <p>Background</p> <p>During the last decade medical students from most Western countries have shown little interest in family practice. Understanding the factors that influence medical students to choose family medicine is crucial.</p> <p>Objective</p> <p>To systematically review and synthesize published evidence about medical studentsâ attitudes and perceptions towards family practice.</p> <p>Methods</p> <p>A qualitative systematic review. The literature search was undertaken in July 2010 in PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Social Science Citation Index (SSCI), and ProQuest Dissertations & Theses. Two authors independently selected the studies for their inclusion and assessed their quality. The selected studies were thoroughly read. Key themes and categories were identified. A matrix was created for allowing the comparison of each theme across studies.</p> <p>Results</p> <p>Ten studies were finally included. Seven broad themes were identified across them: 1) Scope and context of practice was a broad theme comprising linked sub-themes: perception of a varied specialty, broad practice, holistic perspective and flexibility that allows having a family; 2) Lower interest or intellectually less challenging: treating common disease, repetitive, quasi administrative job; 3) Influence of role models, either positive and negative, and society: negative comments from other professionals, peers and family; 4) Lower prestige; 5) Poor remuneration; 6) Medical school influences, being important both the length and quality of the exposure; 7) Post graduate training, where the shorter duration and the lower intensity were perceived as positive aspects. After identifying these seven key themes, were also looked into patterns in the distribution of these themes among studies.</p> <p>Conclusions</p> <p>Our qualitative review provides a comprehensive picture of medical studentsâ attitudes towards family practice in the available literature. In general, although some students find family medicine appealing, it is regarded as a career of low interest and prestige. More research is needed on the influence of role models, medical school and post graduate training.</p