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This research investigates the influence of tibial rotations with knee flexion (KF) on the electromyographic (EMG) activities of hamstring muscles (HM) groups and the strength ratio between the medial and lateral rotation of the tibia. A cross-sectional design was employed to assess muscle activity, isometric strength and reliability. The research was conducted in a controlled laboratory environment. Thirty-six amateur male athletes were recruited as volunteers. The measures included peak muscle activity of the semitendinosus and biceps femoris long head, the knee flexors' isometric strength ratio and reliability. The isometric strength ratios of medial (MR) to lateral (LR) tibial rotations were 0.94 ± 0.17 at 90°, and 0.93 ± 0.10 at both 60° and 30° of KF angulation. Tibial position significantly influenced knee flexion strength as well as HM activity, irrespective of KF angulation. Specifically, biceps femoris activity increased by 33.6% in LR compared to MR, while semitendinosus activity increased by 22.6% in MR compared to LR. The Knee-Rotation test (KR-test) can be a valuable tool for evaluating both HM groups (ICC >0.87), and identifying the primary target for strengthening purposes during the injury prevention process. It provides insights for effective rehabilitation and training interventions. • Reliability was high (ICC >0.87) for the KR-test. • Tibial rotations affect the knee flexion isometric strength. • Hamstring muscle groups should be considered as two separate entities in an assessment perspective. • Lateral rotation constantly increases the biceps femoris muscle activity, but medial rotation does not statistically increases the semitendinosus muscle activity. • The isometric strength ratios of medial/lateral knee flexion strength were 0.94 ± 0.17 at 90° and 0.93 ± 0.10 at 60° and 30° of knee flexion angulation. [ABSTRACT FROM AUTHOR]

The surface and near surface structure of copper-indium-gallium-selenide (CIGS) absorber layers is integral to the producing a high-quality photovoltaic junction. By using X-ray absorption spectroscopy (XAS) and monitoring multiple elemental absorption edges with both theory and experiment, we are able to identify several features of the surface of CIGS as a function of composition and surface treatments. The XAS data shows trends in the near surface region of oxygen, copper, indium and gallium species as the copper content is varied in the films. The oxygen surface species are also monitored through a series of experiments that systematically investigates the effects of water and various solutions of: ammonium hydroxide, cadmium sulfate, and thiourea. These being components of cadmium sulfide chemical bath deposition (CBD). Characteristics of the CBD are correlated with a restorative effect that produces as normalized, uniform surface chemistry as measured by XAS. This surface chemistry is found in CIGS solar cells with excellent power conversion efficiency (

The Askling's H-test is considered a useful return to play criterion after a hamstring muscle injury (HMI). However, it assesses only the active and passive flexibility of posterior thigh muscles. This may lead the practitioner to underestimate a compensation or abnormal movement pattern. The aim of this study was to analyze these kinematic aspects and their reliability, and evaluate the hamstring (HM) and gluteus maximus (GM) muscles' activities. Twelve healthy male volunteers were tested during two session of three trials for passive and active tests. Dynamic flexibility (97.2 ± 6.0°) was significantly greater than the passive one (70.5 ± 14.7°) (p < 0.001), and good intra-individual reproductibility for most kinematic characteristics was observed. Biceps Femoris long head, semitendinosus and GM mean activities (20.1 ± 11.2%; 14.3 ± 7.3% and 25.2 ± 22.1%, respectively) were found to be low to moderate, indicating that only a moderate level of activity occurred during the active H-test, in comparison to other movements such as sprinting itself. In addition, the activity of the posterior thigh muscles during the active H-test appeared to be variable among the volunteers. These findings suggest that the H-test should be interpreted on an individual basis rather than relying on general characteristics, and be considered as an intermediate tool before more strenuous activities such as returning to sprint. With this comprehensive approach, clinicians can gain a more accurate understanding of their patients' progress and make more informed decisions about their readiness to return to play. • Dynamic flexibility was significantly greater than the passive one and good intra-individual reproductibility for most kinematic characteristics was observed. • Biceps Femoris long head, Semitendinosus and Gluteus Maximus mean activities were found moderate during the active H-test. • Posterior thigh muscles' recruitment pattern during the active H-test appeared to be variable among subjects. • H-test characteristics should be evaluated on an individual basis. [ABSTRACT FROM AUTHOR]

We study a one-component quaternionic wave equation which is relativistically covariant. Bilinear forms include a conserved four-vector current and an antisymmetric second rank tensor. Waves propagate within the light cone and there is a conserved quantity which looks like helicity. The principle of superposition is retained in a slightly altered manner. External potentials can be introduced in a way that allows for gauge invariance. There are some results for scattering theory and for two-particle wave functions as well as the beginnings of second quantization. However, we are unable to find a suitable Lagrangian or an energy-momentum tensor. (c) 2006 American Institute of Physics.

Extensive variational computations are reported for the ground state energy of the non-relativistic two-electron atom. Several different sets of basis functions were systematically explored, starting with the original scheme of Hylleraas. The most rapid convergence is found with a combination of negative powers and a logarithm of the coordinate s = r(1) + r(2). At N = 3091 terms we pass the previous best calculation (Korobov's 25 decimal accuracy with N = 5200 terms) and we stop at N = 10257 with E = -2.90372, 43770, 34119, 59831, 11592, 45194, 40444,... Previous mathematical analysis sought to link the convergence rate of such calculations to specific analytic properties of the functions involved. The application of that theory to this new experimental data leaves a rather frustrating situation, where we seem able to do little more than invoke vague concepts, such as "flexibility." We conclude that theoretical understanding here lags well behind the power of available computing machinery.

En dehors des piqûres d'hyménoptères apidés et vespidés, des piqûres ou morsures de nombreux autres arthropodes peuvent donner lieu à des réactions cliniques, de mécanisme allergique ou toxique. Des anaphylaxies ont été décrites avec d'autres hyménoptères comme les fourmis (par exemple la « fourmi de feu » Solenopsis invicta), avec des diptères comme les moustiques et les taons, des hétéroptères comme certaines punaises (« kissing bug », « bed bug »). Parmi les arachnides, des anaphylaxies sont décrites avec certaines espèces de tiques (Ixodes ricinus , Argas reflexus). Un nombre très limité d'espèces d'aranéides (araignées) peut être à l'origine de réactions d'envenimation potentiellement sévères. Le nombre d'espèces dangereuses parmi les scorpions est plus important, mais concerne plutôt l'aspect envenimation que l'aspect immunoallergique de ces réactions. Le traitement des réactions d'envenimation est complexe et l'adrénaline n'y est pas au premier plan. D'autres insectes (simulies, culicoïdes), voire des larves d'insectes (chenilles de lépidoptères), peuvent entraîner des réactions inflammatoires et allergiques, en général peu sévères, utiles à connaître en tant que diagnostic différentiel. Les acariens arboricoles peuvent aussi être à l'origine de manifestations respiratoires proches de celles rencontrées avec les acariens domestiques. Apart from apidae and vespidae hymenoptera stings, many other arthropods can cause clinical reactions, due to allergic or toxic mechanisms. Anaphylactic reactions have been described after stings from other hymenoptera such as ants (for example « imported fire ant ») or bites from diptera (such as mosquitoes or horseflies), heteroptera such as some bugs ("kissing bug", "bed bug"). Among arachnids, anaphylactic reactions have been described after tick bites (Ixodes ricinus , Argas reflexus). A very limited number of spider species can cause potentially serious toxic reactions, which are more frequent among scorpions, rather by envenomation than by immunologic reactions. Treatment of venom toxic reactions is complex and adrenalin does not play the major role. Other insect bites (simuliidae, culicoïdes), even insect larvae (lepidoptera caterpillars) can cause inflammatory and allergic reactions, not very serious usually, but important for differential diagnosis. Spider mites can also be source of respiratory diseases similar to the house dust mites-related diseases. [ABSTRACT FROM AUTHOR]