About the Evaluations of the Environmental Protection Activities’ Effectiveness

A few contemporary examples can be found in various publications to provoke a more profound reflection on the assessment of environmental action. Whatever methodology is used to determine the importance of all types of environmental activities and assess their effectiveness, specific approaches must be adopted. It is crucial to understand that “environmental activities” are not just an appendage to the science of “ecology.” They also represent a specific period in the development of the world, in the second part of the 20th century, during which specific assessments of the effectiveness of human activities are necessarily provided. The science of ecology usually deals with such concepts as biotic, abiotic, and anthropogenic factors. They should account for the specific conditions, impacts, and effects on ecosystems. However, such concepts are also used in other disciplines, which have interests in this field. Therefore, the material in this article will address some critical issues connected to the assessment of the effectiveness of environmental actions

IMPORTANCE OF ELBOW FLEXOR MUSCLE STRENGTH AND ENDURANCE IN SPORTS CLIMBING

The muscles that exert most during sport climbing are the finger flexors followed by elbow flexors (EF). Nevertheless, climbers’ EF strength and endurance have not been tested in an isolated manner and EF endurance has not been assessed at different relative intensities. Purpose: To determine the importance of EF maximal strength and endurance in sports climbing. Methods: Nine male sports climbers and a control group of seven male sports students performed an EF maximal strength (MS) test and four EF endurance tests representing isometric muscle contractions at 90%, 70%, 50% and 30% of the maximal voluntary contraction (MVC). Results: Sports climbers sustained longer than the controls at 70 % (39±11 versus 28±7 s; p=0.044, η2=0.259) and 50%MVC (57±10 versus 48±6 s; p=0.050, η2 =0.248). The highest effect size was estimated for the force-time integral related to body mass at 70% MVC (107±27 versus 75±18 N.s/kg; p=0.018, η2 = 0.338). The two groups did not differ in MS (313±52 versus 338±55 N; p=0.372) or MS related to body mass (4.6±0.6 versus 4.2±0.8 N/kg; p=0.623). Climbing ability significantly correlated only with MS related to body mass. The relationship between MS related to body mass and on sight ability was strong (r=0.806, p=0.016). Conclusion: EF strength and endurance appear to be key performance factors in sports climbing. Sports climbing demands a high level of EF endurance during muscle contractions of high intensity. An excessive increase of EF endurance would not necessary lead to a significant improvement in climbing ability. However, higher climbing ability demands increased EF maximal strength

Active recovery of the finger flexors enhances intermittent handgrip performance in rock climbers

This study aimed to (1) evaluate the effect of hand shaking during recovery phases of intermittent testing on the time–force characteristics of performance and muscle oxygenation, and (2) assess inter-individual variability in the time to achieve the target force during intermittent testing in rock climbers. Twenty-two participants undertook three finger flexor endurance tests at 60% of their maximal voluntary contraction until failure. Performances of a sustained contraction and two intermittent contractions, each with different recovery strategies, were analysed by time–force parameters and near-infrared spectroscopy. Recovery with shaking of the forearm beside the body led to a significantly greater intermittent test time (↑ 22%, P < .05), force–time integral (↑ 28%, P < .05) and faster muscle re-oxygenation (↑ 32%, P < .05), when compared to the hand over hold condition. Further, the ratio of intermittent to continuous test time distinguished specific aerobic muscular adaptations among sport climbers (2.02), boulderers (1.74) and lower grade climbers (1.25). Lower grade climbers and boulderers produced shorter duration contractions due to the slower development of target force during the intermittent test, indicating worse kinaesthetic differentiation. Both the type of recovery and climbing discipline determined muscle re-oxygenation and intermittent performance in rock climbers

Nanophenomena at surfaces: fundamentals of exotic condensed matter phenomena

This book presents the state of the art in nanoscale surface physics. It outlines contemporary trends in the field covering a wide range of topical areas: atomic structure of surfaces and interfaces, molecular films and polymer adsorption, biologically inspired nanophysics, surface design and pattern formation, and computer modeling of interfacial phenomena. Bridging 'classical' and 'nano' concepts, the present volume brings attention to the physical background of exotic condensed-matter properties. The book is devoted to Iwan Stranski and Rostislaw Kaischew, remarkable scientists, who playe

Forearm muscle oxygenation during sustained isometric contractions in rock climbers

Background. Bouldering and lead climbing are divergent disciplines of the sport of rock climbing. Bouldering moves are short and powerful, whilst sport climbing is longer and require a greater degree of endurance. Aim. The aim of this study was to compare forearm muscle oxygenation during sustained isometric contraction between lead climbers (LC) and boulderers (BO). Methods. Eight BO and twelve LC completed maximal finger flexor strength test and sustained contractions to exhaustion at 60% of maximum voluntary contraction (MVC). Differences between BO and LC in maximal strength, time to exhaustion, force time integral (FTI), and tissue oxygenation (SmO2) were assessed by t-test for independent samples. Results. LC showed significantly lower level of average tissue oxygenation (BO 38.9% SmO2, s = 7.4; LC 28.7% SmO2, s = 7.1) and maximal tissue deoxygenation (BO 25.6% SmO2, s = 8.2; LC 13.5% SmO2, s = 8.5). LC demonstrated significantly lower finger flexor strength (519 N, s = 72) than BO (621 N, s = 142). LC sustained a longer time of contraction (not significantly) (BO 52.2 s, s = 11.5; LC 60.6 s, s = 13) and achieved a similar value of FTI (BO 17421 Ns, s = 4291; LO 17476 Ns, s = 5036) in the endurance test. Conclusions. The results showed lower deoxygenation during sustained contraction in BO than LC despite similar FTI, indicating different local metabolic pathways in both groups

Shape changes of two-dimensional atomic islands and vacancy clusters diffusing on epitaxial (1 1 1) interfaces under the impact of an external force

International audienceSurface nanostructures migrate as a consequence of atomic diffusion. Under the effect of a force, arising for instance from an electric current or a thermal gradient (electromigration or thermomigration phenomena), the atomic diffusion is preferential in specific directions and affects the nanostructures making them move and change shape. In this work, based on Kinetic Monte Carlo simulations, we show the impact of an external force on the shapes of 2D atomic islands and vacancy clusters located on homoepitaxial (111) surfaces. At different temperatures, we identify critical values of the strength of the external force applied to the edge atoms, that lead to a series of transitions of the morphology of both islands and vacancy clusters from hexagonal to triangular-like shape. The shape variation is strongly dependent on the external force direction and on the step edge anisotropy