Effect of temperature, food availability, and estradiol injection on gametogenesis and gender in the pearl oyster Pinctada margaritifera

The black-lip pearl oyster Pinctada margaritifera is a protandrous hermaphrodite species. Its economic value has led to the development of controlled hatchery reproduction techniques, although many aspects remain to be optimized. In order to understand reproductive mechanisms and their controlling factors, two independent experiments were designed to test hypotheses of gametogenesis and sex ratio control by environmental and hormonal factors. In one, pearl oysters were exposed under controlled conditions at different combinations of temperature (24 and 28°C) and food level (10,000 and 40,000 cells mL−1); whereas in the other, pearl oysters were conditioned under natural conditions into the lagoon and subjected to successive 17β-estradiol injections (100 μg per injection). Gametogenesis and sex ratio were assessed by histology for each treatment. In parallel, mRNA expressions of nine marker genes of the sexual pathway (pmarg-foxl2, pmarg-c43476, pmarg-c45042, pmarg-c19309, pmarg-c54338, pmarg-vit6, pmarg-zglp1, pmarg-dmrt, and pmarg-fem1-like) were investigated. Maximum maturation was observed in the treatment combining the highest temperature (28°C) and the highest microalgae concentration (40,000 cells mL−1), where the female sex tended to be maintained. Injection of 17β-estradiol induced a significant increase of undetermined stage proportion 2 weeks after the final injection. These results suggest that gametogenesis and gender in adult pearl oysters can be controlled by environmental factors and estrogens. While there were no significant effects on relative gene expression, the 3-gene-pair expression ratio model of the sexual pathway of P. margaritifera, suggest a probable dominance of genetic sex determinism without excluding a mixed sex determination mode (genetic + environmental)

“NYAM CHIEM” RECONSTRUCTING AND PERFORMING NIGHTMARE: A DANCE RESEARCH IN PERFORMANCE OF SLEEP PARALYSIS.

This paper is a documentation of a practice-based dance work of the creative process, research and performance presentation of the piece “Nyam chiem.” This thesis examines the phenomenon of sleep paralysis through a personal reflexive research. The work challenges the notion that sleep paralysis is evil, revealing the phenomenon as a part of the human experience. The research is in two parts, practical and theory. The practical component includes; dance rehearsals, and staging of the piece as presentation. The theoretical component includes the documentation of the work in a written format capturing my personal stories, and salient issues arising from the process into a scholarly paper.

Factors that influence entrepreneurship activity by gender in the European Union

This research work aims to discuss the gender issue concerning entrepreneurship in European Union countries in a period of nine years, from 2007 to 2015, identifying the factors which drive individuals to be entrepreneurs. The study mainly concentrates on identifying and quantifying the personal, social, political and economic features which are motivating individuals, especially women, to be entrepreneurs, as well as the main difficulties they feel during the process of business creation. In order to explore the entrepreneurial activity across a set of developed countries the econometric methodology of panel data (in particular the fixed effects and random effects models) is applied to a data set of entrepreneurial statistical indicators calculated and made available by the Global Entrepreneurship Monitor. The results show that the knowledge of other start-up entrepreneurs, a desired career choice, the governmental support and the existence of public policies that promote entrepreneurship (specially within the framework of small and medium sized firms) and the transfer of R&D are factors influencing negatively on the rate of female entrepreneurship. None of the observed variables are barriers for male entrepreneurs. The perceived capabilities and opportunities, the entrepreneurial intention, the policies to lower taxes and bureaucracy and the social and cultural norms are identified drives for women for engaging in a process of running their own ventures. These findings offer a set of valid knowledge to understand which measures could be implemented or should be changed and improved at a political and managerial level for stimulating entrepreneurship, especially for women.

Differences by gender in barthel index change after stroke: a retrospective study in the Northeast Portugal

Foreseeing functional recovery after stroke plays a crucial role in planning rehabilitation programs. Objectives: To assess differences over time in functional recovery assessed through the Barthel Index (BI) rate of change (BIRC) between admission and discharge in stroke patients. Methods: This is a retrospective hospital-based study of consecutive patients with acute stroke admitted to a hospital in the Northeast Portugal between 2010 and 2014. BIRC was computed as the difference between the admission and discharge BI scores divided by time in days between these assessments. General linear model analysis stratiied by gender was used to know whether there was an increase in BIRC during time period under study. Adjusted regression coeficients and respective 95% conidence interval (95%CI) were obtained. Results: From 483 patients included in this analysis 59% (n = 285) were male. Among women, mean BIRC was 1.8 (± 1.88) units/ day in 2010 and reached 3.7 (± 2.80) units/day in 2014. Among men the mean BIRC in 2010 and in 2014 were similar being 3.2 (± 3.19) and 3.1 (± 3.31) units/day, respectively. After adjustment for age, BI at admission, type and laterality of stroke we observed an increase in BIRC over time among women such that mean BIRC in 2014 was 0.82 (95%: 0.48; 3.69) units higher than the one observed in 2010. No such increase in BIRC over time was observed among men. Conclusions: We observed an improvement in functional recovery after stroke but only among women. Our results suggest differences over time in clinical practice toward rehabilitation of women after stroke.

Moderating effects of gender in the relationships between daily stress, coping styles and hopelessness depression in adolescents

The hopelessness depression (HD) theory assumes a number of contributing factors to the development of hopelessness expectations and HD symptoms. Studies carried out to test HD theory have generally supported the prediction that a negative attributional style contributes to the development of hopelessness expectations and HD symptoms, although the evidence is less consistent for adolescents. Due to these inconsistent results, as well as the assumption advanced by HD theory that other factors aside from attributional style may contribute to the development of HD, in this study we examined the potential role of adolescents’ daily stress and coping styles as contributing factors to HD at these ages, and the effects of gender on these relationships. Seiffge-Krenke (1995) showed that stress in daily life plays a particularly relevant role during adolescence and described three coping styles used by adolescents to face daily stress: active and internal approach-oriented styles, which are considered functional and complementary, and avoidant style, considered dysfunctional. In this study, secondary students (N = 480; aged 13–17) completed the Hopelessness Scale (Beck, Weissman, Lester, & Trexler, 1974), the Hopelessness Depression Symptoms Questionnaire (Metalsky & Joiner, 1997), the Problem Questionnaire ((Seiffge-Krenke, 1995) and the Coping Across Situations Questionnaire (Seiffge-Krenke, 1995). To test the role of daily stress and coping styles in the prediction of hopelessness expectations and HD symptoms, two four-step hierarchical multiple regression analyses were conducted. In these analyses, gender was introduced first, daily stress was introduced second, the three coping styles were entered in a third step, and the moderating effects of gender on the associations of the predictor variables (daily stress and each coping style) with the criterion variables (hopelessness expectations or HD symptoms) were introduced in a fourth step. Results showed a moderating effect of gender on the relationship between daily stress and hopelessness expectations, which revealed a significant effect for boys despite the fact that girls experienced more daily stress than boys, thus suggesting an inoculation effect in girls. It was also found a gender-dependent role of coping styles in the prediction of HD symptoms, revealing a protective effect for the active style in girls and for the internal style in boys. This suggests that girls would benefit from being more action-prone and boys more reflection-prone in order to prevent HD. These findings indicate that programmes aimed to promote coping skills in adolescents would benefit from being gender-adapted.

The role of area-level deprivation and gender in participation in population-based faecal immunochemical test (FIT) colorectal cancer screening

This study aimed to investigate the effects of sex and deprivation on participation in a population-based faecal immunochemical test (FIT) colorectal cancer screening programme. The study population included 9785 individuals invited to participate in two rounds of a population-based biennial FIT-based screening programme, in a relatively deprived area of Dublin, Ireland. Explanatory variables included in the analysis were sex, deprivation category of area of residence and age (at end of screening). The primary outcome variable modelled was participation status in both rounds combined (with “participation” defined as having taken part in either or both rounds of screening). Poisson regression with a log link and robust error variance was used to estimate relative risks (RR) for participation. As a sensitivity analysis, data were stratified by screening round. In both the univariable and multivariable models deprivation was strongly associated with participation. Increasing affluence was associated with higher participation; participation was 26% higher in people resident in the most affluent compared to the most deprived areas (multivariable RR = 1.26: 95% CI 1.21–1.30). Participation was significantly lower in males (multivariable RR = 0.96: 95%CI 0.95–0.97) and generally increased with increasing age (trend per age group, multivariable RR = 1.02: 95%CI, 1.01–1.02). No significant interactions between the explanatory variables were found. The effects of deprivation and sex were similar by screening round. Deprivation and male gender are independently associated with lower uptake of population-based FIT colorectal cancer screening, even in a relatively deprived setting. Development of evidence-based interventions to increase uptake in these disadvantaged groups is urgently required.

Role of gender in transthyretin-related amyloidosis: an international perspective based on the Transthyretin Amyloid Outcomes Survey (THAOS)

Background. Transthyretin amyloidosis (ATTR) is an underdiagnosed disease caused by destabilization of transthyretin (TTR) due to pathogenic mutations (ATTRm) or aging (ATTRwt). We explored the role of gender in determining clinical picture using the largest available database on ATTR, the ongoing Transthyretin Amyloid Outcomes Survey (THAOS) international registry. Methods. Data through 1st April 2019 were explored. Symptomatic ATTRm (n=3737), asymptomatic ATTRm (n=644) and ATTRwt (n=874) patients were studied. Results. Male prevalence was 61% in the entire registry, 53% in ATTRm and 95% in ATTRwt. In the overall cohort, cardiac phenotype was more frequent in males (30.7% vs 10.5%, p<0.001). Among ATTRm, 72.3% of patients with amyloidotic cardiomyopathy (ATTR-CM) were males (p<0.001) but echocardiographic features showed no substantial gender differences. Sensory abnormalities (70.1% vs 64.1%, p<0.001), autonomic abnormalities (60% vs 48.5%, p<0.001) and walking disabilities were more frequent among ATTRm males. Carpal tunnel syndrome was more frequent in ATTRm males (18.6% vs 15.5%, p=0.014). In ATTRwt cohort, females had a more pronounced (but anyhow mild) walking disability. Male-to-female ratio varied within genotype, from 0.61 in Val30Met to 11.11 in ATTRwt; furthermore, males’ imbalance was more evident among symptomatic patients rather than in asymptomatic ones. Male gender, age at presentation and specific genotype were independently associated with the presence of ATTR-CM. Conclusions. In ATTR, cardiac involvement is more frequent in men, supporting the hypothesis that some biologic characteristics may “protect” from myocardial amyloid infiltration in women. Further investigations are needed to identify possible underlying protective mechanism and orient the research for innovative, gender-tailored therapeutic approaches.

Gender effects on performance in Bulgarian private enterprises

Many of the newly established private enterprises in transition economies in Central and Eastern Europe (CEE) are owned and managed by women (Degtiar, 2000). However, there are limited research and knowledge on gender, management, and organization in CEE (Metcalfe and Afanassieva, 2005) and, particularly, on the performance of female-owned companies. Sporadic empirical evidence shows that female-owned companies have worse performance than male-owned companies in transition economies (Drnovsek and Glas, 2006; Aidis, 2006). The purpose of this paper is twofold. First, we study the factors that affect the performance of female-owned companies in a transition context. Second, we compare how performance varies between female and male-owned businesses in such a context. Combining the Feminist Theory, the Institutional Theory, and the literature on determinants of firm performance, we derive hypotheses about the determinants of the performance of female-owned companies and about gender differences in performance. The proposed hypotheses are tested in a sample of 501 private Bulgarian companies. Our results indicate that a number of individual, organizational, and environmental characteristics are significant determinants of the performance of both female and male-owned companies. Although there are gender differences in performance, they disappear when other factors are controlled for. We conclude with some recommendations for policy implications and place the current results in respect to future research.

The impact of gender composition on team performance and decision-making: Evidence from the field

We investigate whether the gender composition of teams affect theireconomic performance. We study a large business game, played in groups ofthree, where each group takes the role of a general manager. There are twoparallel competitions, one involving undergraduates and the other involvingMBAs. Our analysis shows that teams formed by three women aresignificantly outperformed by any other gender combination, both at theundergraduate and MBA levels. Looking across the performancedistribution, we find that for undergraduates, three women teams areoutperformed throughout, but by as much as 10pp at the bottom and by only1pp at the top. For MBAs, at the top, the best performing group is two menand one woman. The differences in performance are explained bydifferences in decision-making. We observe that three women teams are lessaggressive in their pricing strategies, invest less in R&D, and invest more insocial sustainability initiatives, than any other gender combination teams.Finally, we find support for the hypothesis that it is poor work dynamicsamong the three women teams that drives the results.

Category fluency test: effects of age, gender and education on total scores, clustering and switching in Brazilian Portuguese-speaking subjects

Verbal fluency tests are used as a measure of executive functions and language, and can also be used to evaluate semantic memory. We analyzed the influence of education, gender and age on scores in a verbal fluency test using the animal category, and on number of categories, clustering and switching. We examined 257 healthy participants (152 females and 105 males) with a mean age of 49.42 years (SD = 15.75) and having a mean educational level of 5.58 (SD = 4.25) years. We asked them to name as many animals as they could. Analysis of variance was performed to determine the effect of demographic variables. No significant effect of gender was observed for any of the measures. However, age seemed to influence the number of category changes, as expected for a sensitive frontal measure, after being controlled for the effect of education. Educational level had a statistically significant effect on all measures, except for clustering. Subject performance (mean number of animals named) according to schooling was: illiterates, 12.1; 1 to 4 years, 12.3; 5 to 8 years, 14.0; 9 to 11 years, 16.7, and more than 11 years, 17.8. We observed a decrease in performance in these five educational groups over time (more items recalled during the first 15 s, followed by a progressive reduction until the fourth interval). We conclude that education had the greatest effect on the category fluency test in this Brazilian sample. Therefore, we must take care in evaluating performance in lower educational subjects.

Gender diversity and board performance: women's experiences and perspectives

Despite considerable progress that organizations have made during the past 20 years to increase the representation of women at board level, they still hold few board seats. Drawing on a qualitative study involving 30 companies with women directors in the United Kingdom, the United States, and Ghana, we investigate how the relationship between gender in the boardroom and corporate governance operates. The fi ndings indicate that the presence of a minority of women on the board has an insignifi cant effect on board performance. Yet the chairperson’s role is vital in leading the change for recruiting and evaluating candidates and their commitment to the board with diversity and governance in mind. Our study also sheds light on the multifaceted reasons why women directors appear to be resisting the discourse of gender quotas.