Temperature changes of selected body’s surfaces of handball players in the course of training estimated by thermovision,and the study of the impact of physiological and morphological factors on the skin temperature

1.

The aim of this study was to assess the temperature changes in the selected body surfaces (upper extremities—arm and forearm) in response to directed 90 min physical exercise as well as to analyse the impact of physiological and morphological factors on the dynamics of temperature changes.     

Effects of strength training with elastic band programme on fitness components in young female handball players: a randomized controlled trial

This study examined the effect of a 10-week programme of strength training with elastic band (STEB) on fitness components in young female handball players. Twenty-six young female handball players (aged 15.8 ± 0.2 years) from the same club participated in this study. They were randomly assigned between experimental (EG; n = 13) and control (CG; n = 13) groups. The EG performed the STEB, replacing some handball-specific drills in the regular handball training. The CG followed the regular handball training (i.e., mainly technical-tactical drills, small sided and simulated games, and injury prevention drills). Two-way analyses of variance were used to assess: handgrip; back extensor strength; medicine ball throw; 30 m sprint times; Modified Illinois change-of-direction (Illinois-MT); four jump tests: squat jump (SJ), countermovement jump (CMJ), countermovement jump with arm swing (CMJA) and five-jump test (5JT); static (Stork test) and dynamic balance (Y Balance Test); and repeated sprint T-test (RSTT). Results revealed significant gains in handgrip - right (p < 0.001, d = 1.75: large), handgrip - left (p < 0.001, d = 2.52: large), back extensor (p < 0.001, d = 2.01: large), and medicine ball throw (p = 0.002, d = 0.95: large) with EG compared to the CG. The EG also demonstrated greater improvement in sprint performance over 20 m (Δ = 10.6%, p = 0.001, d = 1.07: large) and 30 m (Δ = 7.2%, p < 0.0001, d = 1.56: large) compared to the CG. The EG showed better Illinois-MT (Δ = 5.6%, p = 0.034, d = 0.62: medium) compared to the CG. Further, EG posted significant improvements in the SJ (Δ = 17.3%, p = 0.048, d = 0.58: medium), CMJ (Δ = 17.7%, p = 0.017 d = 0.71: medium), and CMJA (Δ = 16.3%, p = 0.019, d = 0.69: medium) compared to the CG. Similarly, the EG exhibited significant improvement in RSTT best time [p = 0.025, d = 0.66 (medium)], RSTT mean time [p = 0.019, d = 0.69 (medium)] and RSTT total time [p = 0.019, d = 0.69 (medium)] compared to the CG. In conclusion, the 10-week STEB improved the physical abilities in young female handball players.     

Acute effects of dynamic versus foam rolling warm-up strategies on physical performance in elite tennis players

To date, there is a lack of information about the optimal conditions of the warm-up to lead to a better performance in elite tennis players. The aim of this study was to compare the effects of two different warm-up protocols (dynamic vs. self-myofascial release with foam rolling) on neuromuscular variables associated with physical determinants of tennis performance. Using a crossover randomised experimental design, eleven professional men tennis players (20.6 ± 3.5 years) performed either a dynamic warm-up (DWU) or a self-myofascial release with foam rolling (SMFR) protocol. DWU consisted of 8 min of dynamic exercises at increasing intensity and SMFR consisted of 8 min of rolling on each lower extremity unilaterally. Just before (baseline) and after completing warm-up protocols, players performed a countermovement jump (CMJ), the 5-0-5 agility test, a 10-m sprint test and the Straight Leg Raise and Thomas tests to assess range of motion. Compared to baseline, the DWU was more effective to reduce the time in the 5-0-5 test than SMFR (-2.23 vs. 0.44%, respectively, p = 0.042, ηp² = 0.19). However, both warm-up protocols similarly affected CMJ (2.32 vs. 0.61%, p = 0.373, ηp² = 0.04) and 10-m sprint time changes (-1.26 vs. 1.03%, p = 0.124, ηp² = 0.11). Changes in range of motion tests were also similar with both protocols (p = 0.448–1.000, ηp² = 0.00–0.02). Overall, both DWU and SMFR were effective to prepare well-trained tennis players for highly demanding neuromuscular actions. However, DWU offered a better preparation for performing change of direction and sprint actions, and hence, in high-performance tennis players, the warm-up should include dynamic exercises.     

Using matrix of thresholding partial correlation coefficients to infer regulatory network

DNA arrays measure the expression levels for thousands of genes simultaneously under different conditions. These measurements reflect many aspects of the underlying biological processes. A method based on the matrix of thresholding partial correlation coefficients (MTPCC) is proposed for network inference from expression profiles. It includes three main parts: (1) hierarchical cluster analysis, (2) cluster boundaries establishment, and (3) regulatory network inference. The method was applied to the expression data of 2467 genes in Saccharomyces cerevisiae measured under 79 different conditions [Eisen, M.B., Spellman, P.T., Brown, P.O., Botstein, D., 1998. Cluster analysis and display of genome-wide expression patterns. Proc. Natl. Acad. Sci. 95, 14863-14868]. Using hierarchical clustering and cluster boundaries establishment, the 2467 genes were grouped into 12 clusters. The expression profiles of each cluster were expressed as a set of expression levels average over the cluster that constituted genes of each condition. Then the expression data of these clusters were subjected to the analysis of partial correlation, and the significance of each element in the obtained partial correlation coefficient matrix (PCCM) was examined by a permutation test. The corresponding undirected dependency graph (UDG) was obtained as a model of the regulatory network of S. cerevisiae. The veracity of the network was evidenced by the consistency of our results with the collected results from experimental studies.     

Reliability and time-of-day effect on measures of change of direction deficit in young healthy physical education students

ABSTRACT

This study aimed to examine the reliability and the time-of-day effect of the 505 change of direction (CoD), 10-m sprint, and change of direction deficit test (CoDD). At two different time of days, 39 young diurnally active physical education male students performed different physical tests: 505 CoD, and sprint tests. Measurements were taken at two separate testing sessions, i.e. in the morning (07:00–08:30 h) and early evening (17:00–18:30 h) in a randomized and counter-balanced setting on nonconsecutive days in 21 of them (21.5 ± 1.5 y of age). The results showed that the 505 CoD test, 10-m sprint, and CoDD performances were a reliable test, and performances were better in the evening the 505 CoD, 10-m sprint, and CoDD testing provided reliable and sensitive scores. In addition, phase 2 showed that CoD, speed, and CoDD are affected by the time of day.     

The effect of time of day and recovery type after a football game on muscle damage and performance in anaerobic tests on young soccer players

The purpose of this study was to investigate the effect of time of day and different modalities of recovery (active vs. passive recovery) after intermittent exercise in young soccer players. In randomized order, 16 boys participated in the study, divided into two groups: passive recovery (PRG, n?=?8) and active recovery (ARG, n?=?8). Both groups performed tests at 07:00 and 17:00 h. The results showed that performance in the Sargent jump test (SJT), 10-m sprint, and agility were higher in the evening (17:00 h), around the presumed peak of body temperature. SJT and agility performance decreased after the match. The better performance in SJT and agility were found in ARG rather than PRG (p?p?p?p?p?p?相似文献   

Clinging ability is related to particular aspects of foot morphology in salamanders

The interaction between morphology, performance, and ecology has long been studied in order to explain variation in the natural world. Within arboreal salamanders, diversification in foot morphology and microhabitat use are thought to be linked by the impact of foot size and shape on clinging and climbing performance, resulting in an ability to access new habitats. We examine whether various foot shape metrics correlate with stationary cling performance and microhabitat to explicitly quantify this performance gradient across 14 species of salamander, including both arboreal and nonarboreal species. Clinging performance did not correlate with foot shape, as quantified by landmark‐based geometric morphometrics, nor with microhabitat use. Mass‐corrected foot centroid size and foot contact area, on the other hand, correlated positively with clinging performance on a smooth substrate. Interestingly, these foot variables correlated negatively with clinging performance on rough substrates, suggesting the use of multiple clinging mechanisms dependent upon the texture of the surface. These findings demonstrate that centroid size and foot contact area are more functionally relevant for clinging in salamanders than foot shape, suggesting that foot shape need not converge in order to achieve convergent performance. More broadly, our results provide an example of how the quantification of the performance gradient can provide the appropriate lens through which to understand the macroevolution of morphology and ecology.     

Delayed autumn phenology in the Northern Hemisphere is related to change in both climate and spring phenology

The timing of the end of the vegetation growing season (EOS) plays a key role in terrestrial ecosystem carbon and nutrient cycles. Autumn phenology is, however, still poorly understood, and previous studies generally focused on few species or were very limited in scale. In this study, we applied four methods to extract EOS dates from NDVI records between 1982 and 2011 for the Northern Hemisphere, and determined the temporal correlations between EOS and environmental factors (i.e., temperature, precipitation and insolation), as well as the correlation between spring and autumn phenology, using partial correlation analyses. Overall, we observed a trend toward later EOS in ~70% of the pixels in Northern Hemisphere, with a mean rate of 0.18 ± 0.38 days yr^?1. Warming preseason temperature was positively associated with the rate of EOS in most of our study area, except for arid/semi‐arid regions, where the precipitation sum played a dominant positive role. Interestingly, increased preseason insolation sum might also lead to a later date of EOS. In addition to the climatic effects on EOS, we found an influence of spring vegetation green‐up dates on EOS, albeit biome dependent. Our study, therefore, suggests that both environmental factors and spring phenology should be included in the modeling of EOS to improve the predictions of autumn phenology as well as our understanding of the global carbon and nutrient balances.     

长白山北坡林线灌木草本植物与岳桦的动态关系

本文以长白山北坡林线为研究区,调查125个样方内岳桦种群的径级结构与林线灌草植物的生态重要值。采用常规统计和聚类方法分析岳桦种群与8种常见灌草植物的动态特点,采用典型与单因子相关分析岳桦动态与林线灌草植物的变化关系。结果表明岳桦种群扩张带动林下灌草的相继移动,林线上侵不仅是单一乔木的变化,而是森林群落向苔原群落的入侵,从空间上挤占生态位的过程。另外,这种替代中各个成分变化也存在差异,由于各种植物在群落中的地位和生态竞争力的区别,在替代过程中不同植物变化也具有明显的异步性。     

Contrasting adaptation of two Eucalyptus subgenera is related to differences in respiratory metabolism

1. The largest eucalypt subgenus Symphyomyrtus survives and grows better in diverse native and exotic environments than the second largest subgenus Monocalyptus . Previously postulated reasons for this difference, including differential resistance to native insect pests and dependence on specific ectomycorrhizal symbiotic associations with soil fungi, do not fully explain the marked adaptive differentiation.
2. This work shows that differences between the subgenera in survival and growth performance are related to respiratory parameters. We propose that effects of climatic temperature on respiratory metabolism result in Symphyomyrtus being more successful than Monocalyptus in adapting to diverse environments. This suggests a new paradigm for adaptation and evolution of eucalypts.     

Vessel diameter is related to amount and spatial arrangement of axial parenchyma in woody angiosperms

Parenchyma represents a critically important living tissue in the sapwood of the secondary xylem of woody angiosperms. Considering various interactions between parenchyma and water transporting vessels, we hypothesize a structure–function relationship between both cell types. Through a generalized additive mixed model approach based on 2,332 woody angiosperm species derived from the literature, we explored the relationship between the proportion and spatial distribution of ray and axial parenchyma and vessel size, while controlling for maximum plant height and a range of climatic factors. When factoring in maximum plant height, we found that with increasing mean annual temperatures, mean vessel diameter showed a positive correlation with axial parenchyma proportion and arrangement, but not for ray parenchyma. Species with a high axial parenchyma tissue fraction tend to have wide vessels, with most of the parenchyma packed around vessels, whereas species with small diameter vessels show a reduced amount of axial parenchyma that is not directly connected to vessels. This finding provides evidence for independent functions of axial parenchyma and ray parenchyma in large vesselled species and further supports a strong role for axial parenchyma in long‐distance xylem water transport.     

Decrease in required coefficient of friction due to smaller lean angle during turning in older adults

We investigated age-related differences in the required coefficient of friction (RCOF) during 90° turning, the difference of RCOF during step and spin turn, and how affects observed differences. Sixteen healthy young and healthy older adults (eight men and eight women in each group) participated. Participants performed 90° step and spin turns to the right at a self-selected normal speed. Older adults turned with lower RCOF than the young adults during both step and spin turns. This was associated with reduced mediolateral (ML) RCOF component (RCOF_ML) for the older adults. Reduced RCOF_ML in older adults was associated with reductions in the ML component of the lean angle of the body during turning. This age-related gait changes during turning can be compensatory mechanisms that allowed older adults to turn while reducing the risk of slipping. Spin turns exhibited lower RCOF, resulting from significantly lower RCOF_ML, than step turns in young and older adults; thus, spin turning is a safer turning strategy for preventing lateral slips. This may suggest that, in older adults, slip prevention may take precedence over balance recovery after slips sustained during turning. These results illustrate a turning gait mechanism that helps prevent slips and falls, and how age affects this mechanism.     

海南三亚滨海雨林、半落叶季雨林到落叶季雨林的植物群落多样性及种间联结研究

为探索三亚沿海地区(自东向西)从滨海雨林过渡到半落叶季雨林、落叶季雨林的物种多样性及种间关系的变化趋势.该文采用植物群落学调查方法对三种植被类型进行群落调查,进一步使用物种丰富度指数(dGL)、Shannon-Wiener指数(H)、Simpson指数(P)和Pielou均匀度指数(E)来表征各植被类型的物种多样性水平...     

长白山阔叶红松林生态系统碳动态及其对气候变化的响应

应用基于干物质生产理论的过程模型（Sim-CYCLE）估算了1982—2003年间长白山阔叶红松林生态系统总第一生产力（GPP）、净第一生产力（NPP）、净生态系统生产力（NEP）及其季节动态变化以及碳储量（WE）、植物碳储量（WP）和土壤碳储量（WS）,并分析了这些指标在当前气候情景和碳平衡情况时的差异及其对未来气候变化情景的响应.结果表明：在当前气候情景下, 长白山阔叶红松林GPP、NPP和NEP分别为14.9、8.7和2.7 Mg C·hm^-2·a^-1,三者分别比实测值减少2.8 Mg C·hm^-2·a^-1、增加1.4 Mg C·hm^-2·a^-1和增加0.2 Mg C·hm^-2·a^-1;长白山阔叶红松林6—8月的NEP占全年总量的90%以上,其中,7月最高（1.23 Mg C·hm^-2·month^-1）;研究区WE、WP和WS分别为550.8、183.8和367.0Mg C·hm^-2,其与实测值均具有较高的一致性.从当前气候情景下到达碳平衡前,长白山阔叶红松林碳储量均有不同程度的增加,GPP和NPP分别为17.7和7.3 Mg C·hm^-2·a^-1,表明研究区碳“汇”的作用随着碳储量的增加逐渐减弱;温度增加2 ℃时,不利于长白山阔叶红松林GPP、NPP和NEP的增长,CO²浓度倍增则可有利地促进三者的增长,CO²浓度倍增、温度增加2 ℃对GPP、NPP和NEP增幅的影响与单纯CO₂浓度倍增的影响相似,气候变化情景对长白山阔叶红松林碳储量的影响规律与对生产力幅度的影响相同,这可能是生态系统生产力影响碳积累所致.     

The evolution of large brain size in birds is related to social,not genetic,monogamy

There are several hypotheses suggesting that social complexity, including pair bonding, is important in the evolution of increased brain size. I examined whether genetic or social monogamy was related to large brain size in birds. Recent work has indicated that the length and strength of pair bonds are associated with large brain size. I tested several hypotheses for the evolution of large brain size in 42 species of bird by including life history variables in a regression model. A test on 100 phylogenetic trees revealed no phylogenetic signal in brain size. Controlling for body size, a principal components analysis was run on the life history variables and degrees of extra‐pair paternity. The main principal component (PC1) was regressed on brain size revealing a strong, positive association. Social, but not genetic, monogamy was positively related to brain size. Large brain size is related to the selective pressures of procuring extra‐pair copulations whilst maintaining a social partnership. However, other life history variables also loaded positively and significantly on brain size. These results indicate that the evolution of large brain size in birds was driven by several important selective pressures. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 668–678.     

Pulmonary artery relative area change is inversely related to ex vivo measured arterial elastic modulus in the canine model of acute pulmonary embolization

A low relative area change (RAC) of the proximal pulmonary artery (PA) over the cardiac cycle is a good predictor of mortality from right ventricular failure in patients with pulmonary hypertension (PH). The relationship between RAC and local mechanical properties of arteries, which are known to stiffen in acute and chronic PH, is not clear, however. In this study, we estimated elastic moduli of three PAs (MPA, LPA and RPA: main, left and right PAs) at the physiological state using mechanical testing data and correlated these estimated elastic moduli to RAC measured in vivo with both phase-contrast magnetic resonance imaging (PC-MRI) and M-mode echocardiography (on RPA only). We did so using data from a canine model of acute PH due to embolization to assess the sensitivity of RAC to changes in elastic modulus in the absence of chronic PH-induced arterial remodeling. We found that elastic modulus increased with embolization-induced PH, presumably a consequence of increased collagen engagement, which corresponds well to decreased RAC. Furthermore, RAC was inversely related to elastic modulus. Finally, we found MRI and echocardiography yielded comparable estimates of RAC. We conclude that RAC of proximal PAs can be obtained from either MRI or echocardiography and a change in RAC indicates a change in elastic modulus of proximal PAs detectable even in the absence of chronic PH-induced arterial remodeling. The correlation between RAC and elastic modulus of proximal PAs may be useful for prognoses and to monitor the effects of therapeutic interventions in patients with PH.     

黄河上游不同干湿气候区植被对气候变化的响应

 研究气候变化背景下植被变化趋势及其与水热因子的关系, 对于黄河源区的生态恢复和生态建设具有重要意义。采用基于FAO Penman-Monteith的降水蒸散比来描述区域的干湿状况, 划分了黄河上游地区的干湿气候区。在此基础上, 利用AVHRR归一化植被指数(NDVI)和GLOPEM净初级生产力(NPP)数据集和同期的气候资料, 分析了黄河上游植被覆盖、植被生产力和气候变化的趋势, 探讨了不同干湿气候区影响植被变化的主要气候因子。结果表明, 研究区域东南部为半湿润气候区, 其余为半干旱气候区, 干湿气候分界线与450 mm降水等值线较接近; 1981–2006年区域气候趋于干暖化, 尤其是气温的升高趋势明显; 半湿润地区NDVI和NPP显著增加, 半干旱地区略有增加; 半湿润地区的NDVI多与气温显著正相关, 与降水量的相关性较弱, 气温是植被生长的主要气候制约因素; 半干旱地区的NDVI则与降水量的正相关性更强, 对降水量的变化较为敏感。NPP对气候变化的响应模式与NDVI相似。植被对气候变化的响应部分依赖于研究区域所具备的水热条件, 干湿气候划分有助于更好地解释植被对气候变化响应的空间差异。     

Binding of bivalent ions to actinomycete mannanase is accompanied by conformational change and is a key factor in its thermal stability

The study aimed to define the key factors involved in the modulation of actinomycete mannanases. We focused on the roles of carbohydrate-binding modules (CBMs) and bivalent ions. To investigate the effects of these factors, two actinomycete mannanase genes were cloned from Streptomyces thermoluteus (StManII) and Streptomyces lividans (SlMan). CBMs fused to mannanase catalytic domains do not affect the thermal stability of the proteins. CBM2 of StManII increased the catalytic efficiency toward soluble-mannan and insoluble-mannan by 25%–36%, and CBM10 of SlMan increased the catalytic efficiency toward soluble-mannan by 40%–50%. Thermal stability of wild-type and mutant enzymes was enhanced by calcium and manganese. Thermal stability of SlMandC was also slightly enhanced by magnesium. These results indicated that bivalent ion-binding site responsible for thermal stability was in the catalytic domains. Thermal stability of mannanase differed in the kinds of bivalent ions. Isothermal titration calorimetry revealed that the catalytic domain of StManII bound bivalent ions with a K_a of 5.39 ± 0.45 × 10³–7.56 ± 1.47 × 10³ M^− 1, and the catalytic domain of SlMan bound bivalent ions with a K_a of 1.06 ± 0.34 × 10³–3.86 ± 0.94 × 10³ M^− 1. The stoichiometry of these bindings was consistent with one bivalent ion-binding site per molecule of enzyme. Circular dichroism spectrum revealed that the presence of bivalent ions induced changes in the secondary structures of the enzymes. The binding of certain bivalent ion responsible for thermal stability was accompanied by a different conformational change by each bivalent ion. Actinomycete mannanases belong to GHF5 which contained various hemicellulases; therefore, the information obtained from mannanases applies to the other enzymes.     

Evolutionary potential of Chamaecrista fasciculata in relation to climate change. II. Genetic architecture of three populations reciprocally planted along an environmental gradient in the great plains

Climate change will test the evolutionary potential of populations. Information regarding the genetic architecture within and among populations is essential for prediction of evolutionary outcomes. However, little is known about the distribution of genetic variation for relevant traits in natural populations or alteration of genetic architecture in a changing environment. In this study, pedigreed families from three populations of the annual prairie legume Chamaecrista fasciculata were reciprocally transplanted in three environments across a broad latitudinal range in the Great Plains. The underlying premise of this work is that northern populations will in the future experience climates similar to current-day climates further south. Estimates of narrow-sense heritability ranged from 0.053 to 0.481, suggesting the potential for evolutionary change is possible for most traits. In general, the northern population harbored less genetic variation and had lower heritability for traits than the southern population. This population also experienced large reductions in fitness, as measured by estimated lifetime fecundity, when raised in either the intermediate or the southern climate, whereas the difference between the intermediate and southern population was less extreme. For fecundity, the pattern of cross-environment additive genetic correlations was antagonistic to evolutionary change in four of six cases when native and nonnative sites were compared. Six additional antagonistic positive correlations were found for the rate of phenological development and leaf thickness. Overall, the data suggest that if climate changes as predicted, the northern population will face a severe evolutionary challenge in the future because of low heritabilities, cross-environment genetic correlations antagonistic to selection, and demographic instability due to lower seed production in a hotter and drier climate.     

Decrease in membrane hydraulic conductance of rhizodermal cells under nitrate deficit is related to acidification at the root surface

Barley seedlings (Hordeum vulgare L.) were grown on porous plates submerged in Knop medium at pH 6.0 (control) and in a similar nutrient solution where NO ₃ ^? was replaced with Cl^? (treatment); in some treatments Mes buffer (10–20 mM, pH 6.0) was added to the medium. In the absence of buffer, the pH of the medium shifted towards the alkaline region in the presence of NO ₃ ^? and to the acidic region in the presence of Cl^?, with the total shift of no more than 0.3 pH units per day. The replacement of NO ₃ ^? with Cl^? (in a buffer-free medium) decreased the hydraulic membrane conductance of rhizodermal cells (L _p) within a 4-h period; after one day L _p settled at approximately 50% of its initial value observed in untreated plants. When the removal of nitrate from the medium was accompanied by the addition of buffer, no changes in L _p were observed over a 1-day period. The perfusion of external solution (at a rate of 10 mm/s) made it possible to control pH in the proximity to root surface (pH_s). These experiments showed that L _p was independent of the surface pH in the pH_s range 7.0–5.0, whereas at pH_s = 4.5 L _p decreased within 15 min to a steady-state level of about 50% of the control value. It is concluded that the reduction of L _p under nitrate deficit was related to acidification of the medium near the root surface. The acidic pH shift could be caused by the cessation of proton/nitrate symport and by activation of the plasmalemma H⁺-pump, related to changes in the cytosolic pH-stat.