635 research outputs found

    Semi-direct Galois covers of the affine line

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    Let kk be an algebraically closed field of characteristic p>0p>0. Let GG be Z/ZZ/\ell Z semi-direct product Z/pZZ/pZ where \ell is a prime distinct from pp. In this paper, we study Galois covers ψ:ZPk1\psi:Z \to P^1_k ramified only over \infty with Galois group GG. We find the minimal genus of a curve ZZ that admits such a cover and show that it depends only on \ell, pp, and the order aa of \ell modulo pp. We also prove that the number of curves ZZ of this minimal genus which admit such a cover is at most (p1)/a(p-1)/a.Comment: minor changes in the contex

    Breakfast and exercise contingently affect postprandial metabolism and energy balance in physically active males

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    The present study examined the impact of breakfast and exercise on postprandial metabolism, appetite and macronutrient balance. A sample of twelve (blood variables n 11) physically active males completed four trials in a randomised, crossover design comprising a continued overnight fast followed by: (1) rest without breakfast (FR); (2) exercise without breakfast (FE); (3) breakfast consumption(1859 kJ) followed by rest (BR); (4) breakfast consumption followed by exercise (BE). Exercise was continuous, moderate-intensity running (expending approximately 2·9MJ of energy). The equivalent time was spent sitting during resting trials. A test drink (1500 kJ) was ingested on all trials followed 90 min later by an ad libitum lunch. The difference between the BR and FR trials in blood glucose time-averaged AUC following test drink consumption approached significance (BR: 4·33 (SEM 0·14) v. FR: 4·75 (SEM 0·16) mmol/l; P¼0·08); but it was not different between FR and FE (FE: 4·77 (SEM 0·14) mmol/l; P¼0·65); and was greater in BE (BE: 4·97 (SEM 0·13) mmol/l) v. BR(P¼0·012). Appetite following the test drink was reduced in BR v. FR (P¼0·006) and in BE v. FE (P¼0·029). Following lunch, the most positive energy balance was observed in BR and least positive in FE. Regardless of breakfast, acute exercise produced a less positive energy balance following ad libitum lunch consumption. Energy and fat balance is further reduced with breakfast omission. Breakfast improved the overall appetite responses to foods consumed later in the day, but abrogated the appetite suppressive effect of exercise

    Acute and chronic effects of multivitamin/mineral supplementation on objective and subjective energy measures

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    Background: Vitamins and minerals play an essential role within many cellular processes including energy production and metabolism. Previously, supplementation with a multivitamin/mineral (MVM) for ≥28 days resulted in improvements to cognition and subjective state. We have also demonstrated shifts in metabolism during cognitively demanding tasks following MVM in females, both acutely and following 8-week supplementation. The current study aimed to assess these effects further in males and females using metabolically challenging exercise and cognitive tasks. Methods: The current randomised, placebo-controlled, parallel groups study investigated the effects of a MVM complex in 82 healthy young (18-35y) exercisers. Subjective ratings and substrate metabolism were assessed during 30 min each of increasingly effortful incremental exercise and demanding cognitive tasks. Assessments took place on acute study days following a single dose (Day 1) of MVM, containing 3 times recommended daily allowance of water-soluble vitamins plus CoQ10, and following 4-week supplementation (Day 28). Results: Energy expenditure (EE) was increased during cognitive tasks following MVM across Day 1 and Day 28, with greater effects in males. In males, MVM also increased carbohydrate oxidation and energy expenditure during exercise across Day 1 and Day 28. In females, mental tiredness was lower during exercise; increases in physical tiredness following 30 min of exercise were attenuated; and stress ratings following cognitive tasks were reduced following MVM. In males, MVM only lowered mental tiredness following 10 min of exercise. These effects were apparent irrespective of day, but effects on mental tiredness were greater on Day 28. Ferritin levels were also higher on Day 28 in those receiving MVM. Conclusion: These findings extend on existing knowledge, demonstrating increased carbohydrate oxidation and increased energy expenditure in males following MVM supplementation for the first time. Importantly, they show modulation of energy expenditure and subjective tiredness following a single dose, providing further evidence for acute effects of MVM. Differential effects in men and women suggest that sex may play an important role in the effects of MVM on energy metabolism and should be considered in future research. Trial registration: ClinicalTrials.gov, NCT03003442. Registered 22nd November 2016 – retrospectively registere

    Transient Fragments in Outbursting Comet 17P/Holmes

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    We present results from a wide-field imaging campaign at the Canada-France-Hawaii Telescope to study the spectacular outburst of comet 17P/Holmes in late 2007. Using image-processing techniques we probe inside the spherical dust coma and find sixteen fragments having both spatial distribution and kinematics consistent with isotropic ejection from the nucleus. Photometry of the fragments is inconsistent with scattering from monolithic, inert bodies. Instead, each detected fragment appears to be an active cometesimal producing its own dust coma. By scaling from the coma of the primary nucleus of 17P/Holmes, assumed to be 1.7 km in radius, we infer that the sixteen fragments have maximum effective radii between ~ 10 m and ~ 100 m on UT 2007 Nov. 6. The fragments subsequently fade at a common rate of ~ 0.2 mag/day, consistent with steady depletion of ices from these bodies in the heat of the Sun. Our characterization of the fragments supports the hypothesis that a large piece of material broke away from the nucleus and crumbled, expelling smaller, icy shards into the larger dust coma around the nucleus.Comment: 41 pages, 12 figures. Accepted for publication by the Astronomical Journal

    The Interwoven Evolution of the Early Keyboard and Baroque Culture

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    The purpose of this paper is to analyze the impact that Baroque society had in the development of the early keyboard. While the main timeframe is Baroque, a few references are made to the late Medieval Period in determining the reason for the keyboard to more prominently emerge in the musical scene. As Baroque society develops and new genres are formed, different keyboard instruments serve vital roles unique to their construction. These new roles also affect the way music was written for the keyboard as well. Advantages and disadvantages of each instrument are discussed, providing an analysis of what would have been either accepted or rejected by Baroque culture. While music is the main focus, other fine arts are mentioned, including architecture, poetry, politics, and others. My research includes primary and secondary resources retrieved from databases provided by Cedarville University. By demonstrating the relationship between Baroque society and early keyboard development, roles and music, this will be a helpful source in furthering the pianist\u27s understanding of the instrument he or she plays. It also serves pedagogical purposes in its analysis of context in helping a student interpret a piece written during this time period with these early keyboard instruments
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