561 research outputs found

    Coset Symmetries in Dimensionally Reduced Bosonic String Theory

    Get PDF
    We discuss the dimensional reduction of various effective actions, particularly that of the closed Bosonic string and pure gravity, to two and three dimensions. The result for the closed Bosonic string leads to coset symmetries which are in agreement with those recently predicted and argued to be present in a new unreduced formulation of this theory. We also show that part of the Geroch group appears in the unreduced duality symmetric formulation of gravity recently proposed. We conjecture that this formulation can be extended to a non-linear realisation based on a Kac-Moody algebra which we identify. We also briefly discuss the proposed action of Bosonic M-theory.Comment: Reference adde

    Accuracy of reporting food energy intake: Influence of ethnicity and body weight status in South African women

    Get PDF
    The current study sought to identify characteristics that may be associated with the misreporting of food energy intake (EI) in urban South African women. A total of 198 women (61 black, 76 of mixed ancestry, 61 white) completed a quantified food frequency questionnaire, from which daily energy and macronutrient intake were calculated. Body composition (body mass index [BMI], percentage of body fat), body image (Feel-Ideal Difference index and Body Shape questions) and socio-economic status (SES) (household density and asset index) were also measured. Food EI in relation to estimated basal metabolic rate ratio that was less than 1.05 represented under-reporting, whereas a ratio greater than 2.28 represented over-reporting. Results suggested that 26% of the participants under-reported, 64% adequately reported and 10% over-reported. Participants who under-reported had a higher BMI (p < 0.01) and higher percentage of body fat (p < 0.05) than those who adequately and over-reported. The majority of under-reporters were black (38%) versus 21% under-reporters of mixed ancestry and 20% white under-reporters (p < 0.01). Eighty-three per cent of black under-reporters were obese. On the other hand, a majority (63%) of overweight women of mixed ancestry and a majority (50%) of white normal-weight women under-reported their food EI. Under-reporters reported a lower intake of dietary fat (p < 0.01) and a higher intake of dietary protein (p < 0.01) than adequate or over-reporters. Food EI reporting was not influenced by SES or body image. In conclusion, results suggest that food EI reporting is influenced by body size, and may be ethnic-specific in South African women

    Precarious Work Schedules as a Source of Economic Insecurity and Institutional Distrust

    Get PDF
    Work schedules may fuel precariousness among U.S. workers by undermining perceptions of security, both economic and societal. Volatile hours, limited schedule input, and short advance notice are all dimensions of precarious work schedules. Our analyses suggest that scheduling practices that introduce instability and unpredictability into workers’ lives undermine perceptions of security in unique ways for hourly and salaried workers. Although the data suggest that precarious scheduling practices are widespread in the labor market, workers who are black, young, and without a college degree appear to be at highest risk. The findings highlight the importance of examining constellations of scheduling practices and considering the direction of work-hour fluctuations when investigating the ramifications of today’s scheduling practices for quality of employment and quality of life

    Gravitational theories coupled to matter as invariant theories under Kac-Moody algebras

    Get PDF
    Many recent researches indicate that several gravitational D-dimensional theories suitably coupled to some matter fields (including in particular pure gravity in D dimensions, the low energy effective actions of the bosonic string and the bosonic sector of M-theory) would be characterized by infinite dimensional Kac-Moody algebras G^{++} and G^{+++}. The possible existence of these extended symmetries motivates a development of a new description of gravitational theories based on these symmetries. The importance of Kac-Moody algebras and the link between the G^{+++}-invariant theories and the uncompactified space-time covariant theories are discussed.Comment: 7 pages, 1 figure, Contribution to the proceedings of the RTN project 'Constituents, Fundamental Forces and Symmetries of the Universe' conference in Napoli, October 9-13, 200

    Иерархическая организация мира, интеллект и сознание

    Get PDF
    Отказ от фиксированной сложности элементов нижележащих уровней позволил показать, что с точки зрения иерархической организации неживые тела, живые организмы и сознание существуют одинаковым образом, как физическая реальность. Такие свойства сознания, как целостность, контекстность, переживание и чувствование, можно описать только с позиции физического существования, но не формальных или алгоритмических систем. Делается вывод, что сознание не может быть получено с помощью машины Тьюринга и иных вычислительных систем, основанных на формальных принципах.Відмова від фіксованої складності елементів долішніх рівней дозволили показати, що з точки зору ієрархічної організації неживі тіла, живі організми та свідомість існують однаковим чином, як фізична реальність. Такі властивості свідомості, як цілісність, контекстність, переживання та почування, можливо описати лише за позиції фізичного існування, але не формальних або алгоритмічних систем. Робиться висновок, що свідомість не може бути отримана з допомогою машини Тьюрінгу і інших обчислювальних систем, заснованих на формальних принципах.Refusal from fixed complexity of elements of underlying levels has allowed to show that from the point of view of the hierarchical organization lifeless bodies, live organisms and consciousness exist equally, as a physical reality. Such properties of consciousness as integrity, contextual, and feeling it is possible to reproduce experience only from a position of physical existence, but not formal or algorithmic systems. The conclusion becomes that the consciousness cannot be received by means of the machine of the Turing and other computing systems based on formal principles

    Centralized injustices: understanding energy resilience in times of disruption in low-income settlements in Peru

    Get PDF
    What happens once people have electricity has received far less analytical and policy attention than the provision of the infrastructure itself. For low-income settlements that have gained a connection to the grid, energy access challenges can still prevail, keeping many inhabitants in energy poverty. This paper analyses energy practices in three low-income neighbourhoods in Lima, Peru, with particular attention to inhabitants’ responses in the face of the COVID-19 pandemic. In doing so, it seeks to draw lessons for energy policy and planning to enhance energy resilience in the transition towards more just and sustainable futures. Building on energy resilience scholarship and drawing links with justice debates, this paper discusses three community coping strategies: (1) fuel stacking; (2) collective practices and the shared economy; and (3) material and spatial changes. It analyses how these strategies relate to dominant policy directions, as well as their implications for energy resilience and justice more broadly

    Constraints on Automorphic Forms of Higher Derivative Terms from Compactification

    Full text link
    By dimensionally reducing the higher derivative corrections of ten-dimensional IIB theory on a torus we deduce constraints on the E_{n+1} automorphic forms that occur in d=10-n dimensions. In particular we argue that these automorphic forms involve the representation of E_{n+1} with fundamental weight \lambda^{n+1}, which is also the representation to which the string charges in d dimensions belong. We also consider a similar calculation for the reduction of higher derivative terms in eleven-dimensional M-theory.Comment: Minor corrections, to appear in JHE

    Diversity of fishing métier use can affect incomes and costs in small-scale fisheries

    Get PDF
    The implementation of an ecosystem based approach to fisheries management (EBFM) in multispecies fleets has the potential to increase fleet diversification strategies, which can reduce pressure on overexploited stocks. However, diversification may reduce the economic performance of individual vessels and lead to unforeseen outcomes. We studied the economic performance of different fleet segments and their fishing métiers in Wales (UK) to understand how the number of the métiers employed affects fishing income, operating costs and profit. For the small-scale segment more specialized fishers are more profitable and the diversity of métiers is limiting both the maximum expected income and profit but also on the operating costs. This last result may explain the propensity of fishers to increase the number of métiers for at least part of the studied fleet. Therefore, while for some vessels increasing the diversity of fishing métiers may be perceived to limit economic risk associated with the interannual variability of catches and prices and/or to reduce their operating costs, it can ultimately result in a less profitable activity than more specialised vessels.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    Fasting substrate oxidation in relation to habitual dietary fat intake and insulin resistance in non-diabetic women: a case for metabolic flexibility?

    Get PDF
    BACKGROUND: Metabolic flexibility described as "the capacity of the body to match fuel oxidation to fuel availability" has been implicated in insulin resistance. We examined fasting substrate oxidation in relation to dietary macronutrient intake, and markers of insulin resistance in otherwise healthy women, with and without a family history of diabetes mellitus (FH DM). METHODS: We measured body composition (dual x-ray absorptiometry), visceral and subcutaneous adipose tissue area (VAT, SAT, using Computerised Tomography), fasting [glucose], [insulin], [free fatty acids], [blood lipids], insulin resistance (HOMA-IR), resting energy expenditure (REE), respiratory exchange ratio(RER) and self-reported physical activity in a convenience sample of 180 women (18-45 yrs). A food frequency questionnaire was used to assess energy intake (EI) and calculate the RER: Food Quotient (FQ) ratio. Only those with EI:REE (1.05 -2.28) were included (N=140). Insulin resistance was defined HOMA-IR (>1.95). RESULTS: The Insulin Resistant (IR) group had higher energy, carbohydrate and protein intakes (p<0.05) and lower PA levels than Insulin Sensitive (IS) group (P<0.001), but there were no differences in RER or RER:FQ between groups. However, nearly 50% of the variance in HOMA-IR was explained by age, body fat %, VAT, RER:FQ and FH DM (adjusted R2=0.50, p<0.0001). Insulin-resistant women, and those with FH DM had a higher RER:FQ than their counterparts (p<0.01), independent of body fat % or distribution. CONCLUSION: In these apparently healthy, weight-stable women, insulin resistance and FH DM were associated with lower fat oxidation in relation to dietary fat intake, suggesting lower metabolic flexibility
    corecore