Optimal performance of voltage-probe quantum heat engines

The thermoelectric performance at a given output power of a voltage-probe heat engine, exposed to an external magnetic field, is investigated in linear irreversible thermodynamics. For the model, asymmetric parameter, general figures of merit and efficiency at a given output power are analytically derived. Results show a trade-off between efficiency and output power, and we recognize optimum-efficiency values at a given output power are enhanced compared to a B\"uttiker-probe heat engine due to the presence of a characteristic parameter, namely $d_m$. Moreover, similar to a B\"uttiker-probe heat engine, the universal bounds on the efficiency are obtained, and the efficiency at a given output power can exceed the Curzon-Ahlborn limit. These findings have practical implications for the optimization of realistic heat engines and refrigerators. By controlling the values of the asymmetric parameter, the figures of merit, and $d_m$, it may be possible to design more efficient and powerful thermoelectric devices.Comment: 14 pages including 6 multi-panel figure

The Effect of Fiscal Decentralization on Under-five Mortality in Iran: A Panel Data Analysis

Background: Fiscal Decentralization (FD) in many cases is encouraged as a strong means of improving the efficiency and equity in the provision of public goods, such as healthcare services. This issue has urged the researchers to experimentally examine the relationship between fiscal decentralization indicators and health outcomes. In this study we examine the effect of Fiscal Decentralization in Medical Universities (FDMU) and Fiscal Decentralization in Provincial Revenues (FDPR) on Under-Five Mortality Rate (U5M) in provinces of Iran over the period between 2007 and 2010. Methods: We employed panel data methods in this article. The results of the Pesaran CD test demonstrated that most of the variables used in the analysis were cross-sectionally dependent. The Hausman test results suggested that fixed-effects were more appropriate to estimate our model. We estimated the fixed-effect model by using Driscoll-Kraay standard errors as a remedy for cross-sectional dependency. Results: According to the findings of this research, fiscal decentralization in the health sector had a negative impact on U5M. On the other hand, fiscal decentralization in provincial revenues had a positive impact on U5M. In addition, U5M had a negative association with the density of physicians, hospital beds, and provincial GDP per capita, but a positive relationship with Gini coefficient and unemployment. Conclusion: The findings of our study indicated that fiscal decentralization should be emphasized in the health sector. The results suggest the need for caution in the implementation of fiscal decentralization in provincial revenues

The effects of letrozole-induced maternal hyperandrogenism on sexual behaviors, testicular histology, and serum biochemical traits in male offspring rats: An experimental study

Background: Intrauterine endocrine abnormalities have profound effects on the development of physiological disorders. Objective: This study aimed to assess the effects of in utero exposure to letrozole (an aromatase inhibitor) and its late consequences on the reproductive and metabolic performance of an adult male offspring. Materials and Methods: 15 pregnant Sprague-Dawley rats (8 wk, 155 gr) were randomly assigned into 5 experimental groups (n = 3/each) and orally received either letrozole at doses of 0.25, 0.75, 1.00, and 1.25 mg/kg body weight (BW) or vehicle (control) on the gestation days of 16, 17, and 18. Pregnancy outcome, sexual behaviors on postnatal day 60, serum biochemical features, and the histopathology of testes were assessed in male offspring. Results: Compared to control group, delayed labor (21.83 vs. 24.25, p < 0.0001) and reduced litter size (n = 12.25 vs. n = 2, p < 0.0001) were recorded in 1.25 mg/kg BW group. A reduction in high-density lipoprotein level and the elevation of testes weight, BW gain, anogenital distance, as well as the serum concentrations of testosterone, triglycerides, cholesterol, and glucose were observed in 1.25 mg/kg BW (p < 0.0001) and 1.00 mg/kg BW (p < 0.0001) groups in comparison to control. A larger number of anogenital female sniffing, pursuit, and mounting behaviors were also observed in 1.25 mg/kg BW group in comparison to control (p < 0.0001). Severe testicular defects including necrosis and disruption of the epithelium of seminiferous tubules, sloughing of epithelial cells, and spermatogenesis arrest were observed in letrozole-treated groups, in a dose-dependent manner. Conclusion: Maternal exposure to letrozole can adversely affect the reproductive and metabolic performance of male offspring rats, suggesting an incomplete sex differentiation. Key words: Androgens, Aromatase inhibitors, Rat, Sexual activities, Testes histopathology

The Effect of Fiscal Decentralization on Under-five Mortality in Iran: A Panel Data Analysis

Background: Fiscal Decentralization (FD) in many cases is encouraged as a strong means of improving the efficiency and equity in the provision of public goods, such as healthcare services. This issue has urged the researchers to experimentally examine the relationship between fiscal decentralization indicators and health outcomes. In this study we examine the effect of Fiscal Decentralization in Medical Universities (FDMU) and Fiscal Decentralization in Provincial Revenues (FDPR) on Under-Five Mortality Rate (U5M) in provinces of Iran over the period between 2007 and 2010. Methods: We employed panel data methods in this article. The results of the Pesaran CD test demonstrated that most of the variables used in the analysis were cross-sectionally dependent. The Hausman test results suggested that fixed-effects were more appropriate to estimate our model. We estimated the fixed-effect model by using Driscoll-Kraay standard errors as a remedy for cross-sectional dependency. Results: According to the findings of this research, fiscal decentralization in the health sector had a negative impact on U5M. On the other hand, fiscal decentralization in provincial revenues had a positive impact on U5M. In addition, U5M had a negative association with the density of physicians, hospital beds, and provincial GDP per capita, but a positive relationship with Gini coefficient and unemployment. Conclusion: The findings of our study indicated that fiscal decentralization should be emphasized in the health sector. The results suggest the need for caution in the implementation of fiscal decentralization in provincial revenues

Fungicidal effect of Origanum vulgare essential oil against Candida glabrata and its cytotoxicity against macrophages

Introduction: Candida glabrata is a yeast fungus regularly isolated from patients with impaired immunity who receive a routine antifungal therapy. Drug-resistant strains of C. glabrata have been emerged in recent years. The aim of this study was to examine the therapeutic efficacy Origanum vulgare essential oil (OVEO) against drug-resistant strains of C. glabrata and its cytotoxic effect on macrophages.Methods: Specimens were collected from mucosal surfaces of the oral cavity of medically approved oropharyngeal candidiasis (OPC) in HIV-positive patients and volunteered healthy individuals using sterile swabs or mouthwashes. In vitro antifungal susceptibility testing was done using microdilution and disc diffusion methods. Chemical composition of OVEO was determined using gas chromatography mass spectrometry. The cytotoxic effect of essential oil on macrophages was examined using tetrazolium dye (MTT).Results: Minimum inhibitory concentration (MIC) range of OVEO in healthy individuals and OPC patients was 150-200 and 150-250 &mu;g/mL, respectively. OVEO efficiently inhibited growth of resistant isolates. In isolates obtained from HIV patients, both MIC50 and MIC90 of OVEO were 200 &mu;g/mL while in healthy individuals were 150 and 200 &mu;g/mL, respectively. Moreover, OVEO induced significant reduction in proliferation of murine RAW264.7 and peritoneal macrophages in concentrations higher than 100 and 300 &mu;g/mL, respectively. Main constituents of OVEO were thymol (27.3), &gamma;-terpinene (20.7) and carvacrol (16.1).Conclusion: OVEO could be used as a fungicidal agent against fungal infections caused by azole-resistant C. glabrata. A combination therapy along with standard antifungals is suggested to avoid its cytotoxic effects.</p

Cancer Screening: Knowledge, Attitudes, and Practices among Healthcare Personnel

Background: It is crucial for medical personnel to be aware of cancer symptoms and engage in appropriate screening practices. This study aimed to investigate the knowledge of Iranian healthcare staff regarding cancer warning symptoms, their attitudes towards cancer risk factors, and their willingness to undertake cancer screening tests.Method: This cross-sectional study involved administering validated questionnaires to 145 medical staff. In addition to descriptive statistics, independent sample t-test and Analysis of Variance (ANOVA) were utilized to compare knowledge, attitudes, and performance of cancer screening tests. Pearson's correlation coefficient was used to determine the relationship between demographic and occupational variables and participants' knowledge and attitudes regarding cancer risk factors and screening practices.Results: The mean knowledge and attitude scores were 7.97 ± 2.01 and 35.41 ± 4.69, respectively. Among the 125 female participants aged 25-57 years, only 44% performed monthly breast self-examinations, 22.1% sought specialist physicians for breast cancer screening, and only 20.51% of female participants over the age of 40 underwent mammography. Regarding cervical cancer screening, 27.2% had undergone annual Pap smear tests, and 17.6% referred to a specialist for annual pelvic examinations. Among staff older than 45 years (24 participants), only one had undertaken an occult blood test and colonoscopy for colorectal cancer screening.Conclusion: Although most healthcare workers demonstrated awareness of cancer warning signs, they did not engage in regular preventive screening practices. Regular educational programs should be implemented to encourage healthcare personnel to perform routine cancer screening

Volume Changes After Traumatic Spinal Cord Injury in Animal Studies - A Systematic Review

There are limited data on the lesion volume changes following spinal cord injury (SCI). In this study, a meta-analysis was performed to evaluate the volume size changes of the injured spinal cord over time among animal studies in traumatic SCI. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a comprehensive electronic search of English literature of PubMed and EMBASE databases from 1946 to 2015 concerning the time-dependent changes in the volume of the spinal cord following mechanical traumatic SCI. A hand-search was also performed for non-interventional, non-molecular, and non-review studies. Quality appraisal, data extraction, qualitative and quantitative analyses were performed afterward. Of 11,561 articles yielded from electronic search, 49 articles were assessed for eligibility after reviewing of titles, abstracts, and references. Ultimately, 11 articles were eligible for quantitative synthesis. The ratio of lesion volume to spinal cord total volume increased over time. Avascularity appeared in spinal cord 4 hours after injury. During the first week, the spinal subarachnoid space decreased. The hemorrhagic lesion size peaked in 1 week and decreased thereafter. Significant loss of gray and white matter occurred from day 3 with a slower progression of white matter damage. Changes of lesion extent over time is critical in pathophysiologic processes after SCI. Early avascularity, rapid loss of gray matter, slow progression of white matter damage, and late cavitation are the pathophysiologic key points of SCI, which could be helpful in choosing the proper intervention on a timely basis

Social Skills in Preschool Children from Teachers’ Perspectives

Abstract: Preschool is one of the most important periods in a child’s life, and it can influence their social development. A lack of attention to this important life period can increase the risk of serious injuries to a child’s growth and development. The aim of this study was to examine the level of social skills in preschool children from teachers’ perspectives and investigate the relationship between social skills and the child’s environmental and cultural background. A cross-sectional study was conducted on 546 children studying in the preschool centers of Rasht city, Iran. They were selected using a multistage cluster sampling method. Data was gathered using the children’s and teachers’ demographic questionnaire and the Social Skills Rating System-Teachers (SSRS-T). Descriptive and inferential statistics were used for data analysis via SPSS software. It was found that the majority of children had moderate skills in terms of cooperation, assertion, self-control, and total social skills. Also, a statistically significant association was reported between total social skill scores and the mother’s age, mother’s education level, mother’s job, family’s income, teacher teaching experiences, and number of children in each classroom. The Iranian children were at a relatively low risk of problems with social skills. To improve children’s social skills, more attention should be paid to factors related to familial and socioeconomic status such as income, parents’ education level, maternal age, teacher’s selection for this age group, and number of children in each classroom