642 research outputs found

    Liouville theory and the Weil-Petersson geometry of moduli space: bordered, conic, and higher genus surfaces

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    Two-dimensional conformal field theory is a powerful tool to understand the geometry of surfaces. Here, we study Liouville conformal field theory in the classical (large central charge) limit, where it encodes the geometry of the moduli space of Riemann surfaces. Generalizing previous work, we employ this to study moduli spaces of higher genus surfaces, surfaces with boundaries, and surfaces with cone points. In each case, the knowledge of classical conformal blocks provides an extremely efficient approximation to the Weil-Petersson metric on moduli space. We find detailed agreement with analytic results for volumes and geodesic lengths on moduli space.Comment: 38 pages, 9 figure

    Multidimensional apathy in behavioural variant frontotemporal dementia, primary progressive aphasia and Alzheimer’s disease

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    Apathy is prevalent in dementia, such as behavioral variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA), and Alzheimer disease (AD). As a multidimensional construct, it can be assessed and subsumed under a Dimensional Apathy Framework. A consistent apathy profile in bvFTD and PPA has yet to be established. The aim was to explore apathy profiles and awareness in bvFTD, PPA, and AD. A total of 12 patients with bvFTD, 12 patients with PPA, 28 patients with AD, and 20 matched controls, as well as their informants/carers, were recruited. All participants completed the Dimensional Apathy Scale (DAS), assessing executive, emotional, and initiation apathy subtypes, a 1-dimensional apathy measure, depression measure, and functional and cognitive screens. Apathy subtype awareness was determined through DAS informant/carer and self-rating discrepancy. Apathy profile comparison showed patients with bvFTD had significantly higher emotional apathy than patients with AD (P <.01) and significantly higher apathy over all subtypes than patients with PPA (Ps <.05). Additionally, patients with bvFTD had significantly lower awareness for emotional apathy (P <.01) when compared to patients with AD and PPA. All patient groups had significant global apathy over all subtypes compared to controls. The emergent apathy profile for bvFTD seems to be emotional apathy (indifference or emotional/affective neutrality), with lower self-awareness in this subtype. Further, lower self-awareness for executive apathy (lack of motivation for planning, organization, or attention) differentiates bvFTD from PPA. Future research should investigate the cognitive and neural correlates as well as the practical impact of apathy subtypes

    Roles of spatial scale and rarity on the relationship between butterfly species richness and human density in South Africa

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    Wildlife and humans tend to prefer the same productive environments, yet high human densities often lead to reduced biodiversity. Species richness is often positively correlated with human population density at broad scales, but this correlation could also be caused by unequal sampling effort leading to higher species tallies in areas of dense human activity. We examined the relationships between butterfly species richness and human population density at five spatial resolutions ranging from 2' to 60' across South Africa. We used atlas-type data and spatial interpolation techniques aimed at reducing the effect of unequal spatial sampling. Our results confirm the general positive correlation between total species richness and human population density. Contrary to our expectations, the strength of this positive correlation did not weaken at finer spatial resolutions. The patterns observed using total species richness were driven mostly by common species. The richness of threatened and restricted range species was not correlated to human population density. None of the correlations we examined were particularly strong, with much unexplained variance remaining, suggesting that the overlap between butterflies and humans is not strong compared to other factors not accounted for in our analyses. Special consideration needs to be made regarding conservation goals and variables used when investigating the overlap between species and humans for biodiversity conservation.SM was supported by a postdoctoral fellowship from the University of Pretoria (www.up.ac. za), followed by one from the South African National Biodiversity Institute (www.sanbi.org.za). RA was supported by the National Research Foundation of South Africa (Grant 85802; www.nrf.ac.za). JFC was supported by a National Research Foundation of South Africa's Research Career Award Fellowship.http://www.plosone.orgam201

    Risk of hospital admission with covid-19 among teachers compared with healthcare workers and other adults of working age in Scotland, March 2020 to July 2021:population based case-control study

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    Objective: To determine the risk of hospital admission with covid-19 and severe covid-19 among teachers and their household members, overall and compared with healthcare workers and adults of working age in the general population. Design: Population based nested case-control study. Setting: Scotland, March 2020 to July 2021, during defined periods of school closures and full openings in response to covid-19. Participants: All cases of covid-19 in adults aged 21 to 65 (n=132 420) and a random sample of controls matched on age, sex, and general practice (n=1 306 566). Adults were identified as actively teaching in a Scottish school by the General Teaching Council for Scotland, and their household members were identified through the unique property reference number. The comparator groups were adults identified as healthcare workers in Scotland, their household members, and the remaining general population of working age. Main outcome measures: The primary outcome was hospital admission with covid-19, defined as having a positive test result for SARS-CoV-2 during hospital admission, being admitted to hospital within 28 days of a positive test result, or receiving a diagnosis of covid-19 on discharge from hospital. Severe covid-19 was defined as being admitted to intensive care or dying within 28 days of a positive test result or assigned covid-19 as a cause of death. Results: Most teachers were young (mean age 42), were women (80%), and had no comorbidities (84%). The risk (cumulative incidence) of hospital admission with covid-19 was &lt;1% for all adults of working age in the general population. Over the study period, in conditional logistic regression models adjusted for age, sex, general practice, race/ethnicity, deprivation, number of comorbidities, and number of adults in the household, teachers showed a lower risk of hospital admission with covid-19 (rate ratio 0.77, 95% confidence interval 0.64 to 0.92) and of severe covid-19 (0.56, 0.33 to 0.97) than the general population. In the first period when schools in Scotland reopened, in autumn 2020, the rate ratio for hospital admission in teachers was 1.20 (0.89 to 1.61) and for severe covid-19 was 0.45 (0.13 to 1.55). The corresponding findings for household members of teachers were 0.91 (0.67 to 1.23) and 0.73 (0.37 to 1.44), and for patient facing healthcare workers were 2.08 (1.73 to 2.50) and 2.26 (1.43 to 3.59). Similar risks were seen for teachers in the second period, when schools reopened in summer 2021. These values were higher than those seen in spring/summer 2020, when schools were mostly closed. Conclusion: Compared with adults of working age who are otherwise similar, teachers and their household members were not found to be at increased risk of hospital admission with covid-19 and were found to be at lower risk of severe covid-19. These findings should reassure those who are engaged in face-to-face teaching

    Мультипарадигмальний підхід до аналізу феномену нігілізму

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    У статті розглянуто нігілізм як неоднозначне й поліморфне поняття. Досліджено різні підходи до тлумачення та розв’язання питань, пов’язаних із нігілізмом. Розкрито людиномірність нігілізму в контексті відстеження варіативного смислового навантаження феномену. Встановлено, що нігілізм потрібно позиціонувати як спосіб пробудження людського духу, заперечення деструктивного конформізму й відсутності опору (пасивний песимізм).В статье рассмотрен нигилизм как неоднозначное и полиморфное понятие. Исследованы различные подходы к толкованию и решению вопросов, связанных с нигилизмом. Раскрыта человекомерность нигилизма в контексте отслеживания вариативной смысловой нагрузки феномена. Установлено, что нигилизм нужно позиционировать как способ пробуждения человеческого духа, отрицание деструктивного конформизма и отсутствия сопротивления (пассивный пессимизм).Nihilism is considered as ambiguous and polymorphic concept. Different approaches to the interpretation and solution of issues associated with nihilism are investigated. Human measurement of nihilism in the context of tracking meaning of varied semantic capacity of the phenomenon is revealed. It is determined that nihilism must be positioned as a way of awakening of the human spirit, denial of destructive conformism and absence of resistance (passive pessimism)

    Relation of severe COVID-19 in Scotland to transmission-related factors and risk conditions eligible for shielding support:REACT-SCOT case-control study

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    Abstract Background Clinically vulnerable individuals have been advised to shield themselves during the COVID-19 epidemic. The objectives of this study were to investigate (1) the rate ratio of severe COVID-19 associated with eligibility for the shielding programme in Scotland across the first and second waves of the epidemic and (2) the relation of severe COVID-19 to transmission-related factors in those in shielding and the general population. Methods In a matched case-control design, all 178,578 diagnosed cases of COVID-19 in Scotland from 1 March 2020 to 18 February 2021 were matched for age, sex and primary care practice to 1,744,283 controls from the general population. This dataset (REACT-SCOT) was linked to the list of 212,702 individuals identified as eligible for shielding. Severe COVID-19 was defined as cases that entered critical care or were fatal. Rate ratios were estimated by conditional logistic regression. Results With those without risk conditions as reference category, the univariate rate ratio for severe COVID-19 was 3.21 (95% CI 3.01 to 3.41) in those with moderate risk conditions and 6.3 (95% CI 5.8 to 6.8) in those eligible for shielding. The highest rate was in solid organ transplant recipients: rate ratio 13.4 (95% CI 9.6 to 18.8). Risk of severe COVID-19 increased with the number of adults but decreased with the number of school-age children in the household. Severe COVID-19 was strongly associated with recent exposure to hospital (defined as 5 to 14 days before presentation date): rate ratio 12.3 (95% CI 11.5 to 13.2) overall. The population attributable risk fraction for recent exposure to hospital peaked at 50% in May 2020 and again at 65% in December 2020. Conclusions The effectiveness of shielding vulnerable individuals was limited by the inability to control transmission in hospital and from other adults in the household. Mitigating the impact of the epidemic requires control of nosocomial transmission
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