698 research outputs found

    Discrete Painleve system and the double scaling limit of the matrix model for irregular conformal block and gauge theory

    Full text link
    We study the partition function of the matrix model of finite size that realizes the irregular conformal block for the case of the N=2{\cal N}=2 supersymmetric SU(2)SU(2) gauge theory with Nf=2N_f =2. This model has been obtained in [arXiv:1008.1861 [hep-th]] as the massive scaling limit of the β\beta deformed matrix model representing the conformal block. We point out that the model for the case of β=1\beta =1 can be recast into a unitary matrix model with log potential and show that it is exhibited as a discrete Painlev\'{e} system by the method of orthogonal polynomials. We derive the Painlev\'{e} II equation, taking the double scaling limit in the vicinity of the critical point which is the Argyres-Douglas type point of the corresponding spectral curve. By the 00d-44d dictionary, we obtain the time variable and the parameter of the double scaled theory respectively from the sum and the difference of the two mass parameters scaled to their critical values.Comment: 12 pages; v2: references added; v3: accepted version for Physics Letters B; v4: minor corrections, published versio

    Revisão da literatura sobre formação continuada de professores de física

    Get PDF
    Pretendemos, no presente estudo, traçar um panorama dos resultados de pesquisas brasileiras recentes sobre a formação continuada dos professores de física e apontar aspectos de interesse para futuras pesquisas na área. Utilizando os descritores formação continuada de professores de física e aprendizagem de professores de física, fizemos um levantamento em teses, dissertações e artigos científicos e selecionamos 46 pesquisas, produzidas no período de 2010 a 2019. Agrupamos as pesquisas segundo suas características. Primeiro, as análises de formações continuadas que discutem com professores conteúdos de física e/ou uma forma de ensiná-lo (47,83% dos trabalhos). Segundo, as análises de formações continuadas em cursos de mestrado (15,22% dos trabalhos). Terceiro, os diagnósticos que apontam necessidades e/ou contribuições para as formações continuadas de professores de física (36,95% dos trabalhos). Em geral, as pesquisas são feitas com referenciais teórico-metodologicos diversificados e, em muitos casos, a formação continuada de professores de física alcança a eficácia desejada. Mas muito ainda precisa ser feito nessa direção, tanto no campo da prática quanto da investigação

    Effects of chronic testosterone administration on the degree of preference for a high-fat diet and body weight in gonadal-intact and ovariectomized female rats

    Get PDF
    Energy balance and reproductive functions are closely linked in some species. The sex hormones (estrogens and androgens) are involved in the regulation of appetite, metabolism, body weight (BW), and body composition in mammals. Previously, we showed that the effects of testosterone on BW, appetite, and fat weight were markedly affected by alterations to the gonadal hormonal milieu. In this study, we examined whether testosterone administration changes food preferences and whether these effects of testosterone depend on gonadal status in female rats. We also evaluated the underlying mechanisms responsible for these effects, focusing on hypothalamic inflammation and endoplasmic reticulum (ER) stress. In gonadal-intact (sham) female rats, chronic testosterone administration promoted a preference for a high-fat diet (HFD) and increased BW gain, fat weight, and adipocyte size, whereas no such effects were observed in ovariectomized (OVX) rats. Testosterone administration increased hypothalamic interleukin-1 mRNA expression in the sham rats, but not the OVX rats. On the contrary, testosterone administration decreased the hypothalamic mRNA levels of ER stress-response genes in the OVX rats, but not the sham rats. These testosterone-induced alterations in OVX rats might represent a regulatory mechanism for preventing hypothalamic inflammation and the overconsumption of a HFD. In conclusion, testosterone’s effects on food preferences and the subsequent changes were affected by gonadal status. Testosterone-induced changes in hypothalamic inflammatory cytokine production and ER stress might be related to these findings

    Pilot study of the optimal protocol of low dose step‐up follicle stimulating hormone therapy for infertile women

    Get PDF
    Purpose: To evaluate the optimized protocol of low dose follicle‐stimulating hormone (FSH) therapy that has a starting dose of 50 IU/62.5 IU with a small increment dose (12.5 IU) for women with World Health Organization (WHO) II ovulatory disorder and unexplained infertility. Methods: Anovulatory women with WHO group II ovulatory disorder (ovulation induction [OI] patients, n = 29), and with an unexplained infertility (ovarian stimulation [OS] patients, n = 21) were enrolled. The protocol of low dose step‐up FSH therapy was optimized for the starting dose as 50 IU (body mass index [BMI] < 20 group) and 62.5 IU (BMI ≥ 20 group) with the increment dose of 12.5 IU. Study outcomes were ovulation, monofollicular development and other variables. Results: In the OIpatients, the ovulation rate was 100% (BMI < 20 group) and 90.9% (BMI ≥ 20 group). Monofollicular development was 80.0% (BMI < 20) and 77.3% (BMI ≥ 20). The pregnancy rate was 60% (3/5 BMI < 20) and 18.2% (4/22 BMI ≥ 20). There was no multiple pregnancy. In the OSpatients, the ovulation rate was 100%. Monofollicular development was 85.7% (BMI < 20) and 76.6% (BMI ≥ 20). No pregnancy was achieved in the OSpatients. Conclusion: Optimized protocol of low dose FSH therapy setting a starting dose 50 IU/62.5 IU by BMI with an increment dose of 12.5 IU was safe and highly effective in WHO group II anovulatory patients. However, this protocol seemed uneffective for patients with unexplained infertility
    corecore