Łojasiewicz-Simon gradient inequalities for coupled Yang-Mills energy functionals

We prove Lojasiewicz–Simon gradient inequalities for coupled Yang–Mills energy functions using Sobolev spaces which impose minimal regularity requirements on pairs of connections and sections. The Lojasiewicz–Simon gradient inequalities for coupled Yang–Mills energy functions generalize that of the pure Yang–Mills energy function due to the first author (Feehan, 2014) for base manifolds of arbitrary dimension and due to R˚ade (1992, Proposition 7.2) for dimensions two and three

Lojasiewicz-Simon gradient inequalities for analytic and Morse-Bott functions on Banach spaces

We prove several abstract versions of the Lojasiewicz-Simon gradient inequality for an analytic functional on a Banach space that generalize previous abstract versions of this inequality, weakening their hypotheses and, in particular, the well-known infinite-dimensional version of the gradient inequality due to Lojasiewicz proved by Simon (1983). We also prove that the optimal exponent of the Lojasiewicz-Simon gradient inequality is obtained when the functional is Morse-Bott, improving on similar results due to Chill (2003, 2006), Haraux and Jendoubi (2007), and Simon (1996). In our article arXiv:1903.01953, we apply our abstract Lojasiewicz-Simon gradient inequalities to prove a Lojasiewicz-Simon gradient inequalities for the harmonic map energy functional using Sobolev spaces which impose minimal regularity requirements on maps between closed, Riemannian manifolds. Those inequalities for the harmonic map energy functional generalize those of Kwon (2002), Liu and Yang (2010), Simon (1983, 1985), and Topping (1997). In our monograph arXiv:1510.03815, we prove Lojasiewicz--Simon gradient inequalities for coupled Yang--Mills energy functions using Sobolev spaces which impose minimal regularity requirements on pairs of connections and sections. Those inequalities generalize that of the pure Yang--Mills energy function due to the first author (Theorems 23.1 and 23.17 in arXiv:1409.1525) for base manifolds of arbitrary dimension and due to Rade (1992) for dimensions two and three

Skill execution and sleep deprivation: effects of acute caffeine or creatine supplementation - a randomized placebo-controlled trial

<p>Abstract</p> <p>Background</p> <p>We investigated the effects of sleep deprivation with or without acute supplementation of caffeine or creatine on the execution of a repeated rugby passing skill.</p> <p>Method</p> <p>Ten elite rugby players completed 10 trials on a simple rugby passing skill test (20 repeats per trial), following a period of familiarisation. The players had between 7-9 h sleep on 5 of these trials and between 3-5 h sleep (deprivation) on the other 5. At a time of 1.5 h before each trial, they undertook administration of either: placebo tablets, 50 or 100 mg/kg creatine, 1 or 5 mg/kg caffeine. Saliva was collected before each trial and assayed for salivary free cortisol and testosterone.</p> <p>Results</p> <p>Sleep deprivation with placebo application resulted in a significant fall in skill performance accuracy on both the dominant and non-dominant passing sides (p < 0.001). No fall in skill performance was seen with caffeine doses of 1 or 5 mg/kg, and the two doses were not significantly different in effect. Similarly, no deficit was seen with creatine administration at 50 or 100 mg/kg and the performance effects were not significantly different. Salivary testosterone was not affected by sleep deprivation, but trended higher with the 100 mg/kg creatine dose, compared to the placebo treatment (p = 0.067). Salivary cortisol was elevated (p = 0.001) with the 5 mg/kg dose of caffeine (vs. placebo).</p> <p>Conclusion</p> <p>Acute sleep deprivation affects performance of a simple repeat skill in elite athletes and this was ameliorated by a single dose of either caffeine or creatine. Acute creatine use may help to alleviate decrements in skill performance in situations of sleep deprivation, such as transmeridian travel, and caffeine at low doses appears as efficacious as higher doses, at alleviating sleep deprivation deficits in athletes with a history of low caffeine use. Both options are without the side effects of higher dose caffeine use.</p

Προστασία Θαλασσίου Περιβάλλοντος απο Ναυτικά Ατυχήματα

Η ναυτιλία είναι γεμάτη από κινδύνους παρά τα υψηλά και συνεχώς αυξανόμενα πρότυπα ασφαλείας. Το ναυτικό ατύχημα είναι ένας όρος που χρησιμοποιείται για οποιοδήποτε ατύχημα προκαλεί οικονομική ζημία, είτε στη ζωή είτε στην περιουσία είτε και στις δύο περιπτώσεις. Διάφοροι κρίσιμοι παράγοντες παίζουν ρόλο στα ναυτικά ατυχήματα όπως οι φυσικές συνθήκες, οι τεχνικές αστοχίες, οι συνθήκες της διαδρομής, οι παράγοντες που σχετίζονται με το πλοίο, τα ανθρώπινα λάθη, οι παράγοντες που σχετίζονται με το φορτίο κτλ. Παραδείγματα κοινών ατυχημάτων αποτελούν η σύγκρουση πλοίων ή η επαφή τους, η ανατροπή, η διάρρηξη, η προσάραξη, η πυρκαγιά ή η έκρηξη σε αυτά, κ.λπ. Ως εκ τούτου, τα ναυτικά ατυχήματα ανά τύπο είναι αρκετά και οι επιπτώσεις τους στο θαλάσσιο περιβάλλον πολύ σημαντικές. Στην εργασία αυτή θα αναφερθούν τα πρότυπα που έχουν θεσπιστεί διεθνώς για τα πλοία, τους ναυτικούς και τη διαχείριση της ναυτιλίας με σκοπό την ασφάλεια της ναυτιλίας και την προστασία του θαλάσσιου περιβάλλοντος.Shipping is full of dangers despite high and ever-increasing security standards. Marine accident is a term used for any accident causing financial damage, either in life or in property, or in both cases. Several critical factors play a role in maritime accidents such as natural conditions, technical failures, route conditions, ship-related factors, human errors, cargo-related factors, etc. Examples of common accidents are ship collision or contact, overturning, burglary, earthing, fire or explosion in them, etc. As a result, maritime accidents by type are quite significant and their impact on the marine environment is very important. This work will report on the internationally established standards for ships, seafarers and maritime management for the safety of shipping and the protection of the marine environment