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101.
102.
RG Lockie AB Schultz SJ Callaghan CA Jordan TM Luczo MD Jeffriess 《Biology of sport / Institute of Sport》2015,32(1):41-51
There is little research investigating relationships between the Functional Movement Screen (FMS) and athletic performance in female athletes. This study analyzed the relationships between FMS (deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise [ASLR]; trunk stability push-up; rotary stability) scores, and performance tests (bilateral and unilateral sit-and-reach [flexibility]; 20-m sprint [linear speed]; 505 with turns from each leg; modified T-test with movement to left and right [change-of-direction speed]; bilateral and unilateral vertical and standing broad jumps; lateral jumps [leg power]). Nine healthy female recreational team sport athletes (age = 22.67 ± 5.12 years; height = 1.66 ± 0.05 m; body mass = 64.22 ± 4.44 kilograms) were screened in the FMS and completed the afore-mentioned tests. Percentage between-leg differences in unilateral sit-and-reach, 505 turns and the jumps, and difference between the T-test conditions, were also calculated. Spearman''s correlations (p ≤ 0.05) examined relationships between the FMS and performance tests. Stepwise multiple regressions (p ≤ 0.05) were conducted for the performance tests to determine FMS predictors. Unilateral sit-and-reach positive correlated with the left-leg ASLR (r = 0.704-0.725). However, higher-scoring HS, ILL, and ASLR related to poorer 505 and T-test performance (r = 0.722-0.829). A higher-scored left-leg ASLR related to a poorer unilateral vertical and standing broad jump, which were the only significant relationships for jump performance. Predictive data tended to confirm the correlations. The results suggest limitations in using the FMS to identify movement deficiencies that could negatively impact athletic performance in female team sport athletes. 相似文献
103.
Cyril C. Grueter Bernard Chapais Dietmar Zinner 《International journal of primatology》2012,33(5):1002-1037
Multilevel (or modular) societies are a distinct type of primate social system whose key features are single-male–multifemale, core units nested within larger social bands. They are not equivalent to fission–fusion societies, with the latter referring to routine variability in associations, either on an individual or subunit level. The purpose of this review is to characterize and operationalize multilevel societies and to outline their putative evolutionary origins. Multilevel societies are prevalent in three primate clades: papionins, Asian colobines, and hominins. For each clade, we portray the most parsimonious phylogenetic pathway leading to a modular system and then review and discuss likely socioecological conditions promoting the establishment and maintenance of these societies. The multilevel system in colobines (most notably Rhinopithecus and Nasalis) has likely evolved as single-male harem systems coalesced, whereas the multilevel system of papionins (Papio hamadryas, Theropithecus gelada) and hominins most likely arose as multimale–multifemale groups split into smaller units. We hypothesize that, although ecological conditions acted as preconditions for the origin of multilevel systems in all three clades, a potentially important catalyst was intraspecific social threat, predominantly bachelor threat in colobines and female coercion/infanticide in papionins and humans. We emphasize that female transfers within bands or genetic relationships among leader males help to maintain modular societies by facilitating interunit tolerance. We still lack a good or even basic understanding of many facets of multilevel sociality. Key remaining questions are how the genetic structure of a multilevel society matches the observed social effort of its members, to what degree cooperation of males of different units is manifest and contributes to band cohesion, and how group coordination, communication, and decision making are achieved. Affiliative and cooperative interunit relations are a hallmark of human societies, and studying the precursors of intergroup pacification in other multilevel primates may provide insights into the evolution of human uniqueness. 相似文献
104.
THORSTEN E. E. GRAMS SILKE LAUTNER HUBERT H. FELLE RAINER MATYSSEK & JÖRG FROMM 《Plant, cell & environment》2009,32(4):319-326
Combining measurements of electric potential and pH with such of chlorophyll fluorescence and leaf gas exchange showed heat stimulation to evoke an electrical signal (propagation speed: 3–5 mm s−1 ) that travelled through the leaf while reducing the net CO2 uptake rate and the photochemical quantum yield of both photosystems (PS). Two-dimensional imaging analysis of the chlorophyll fluorescence signal of PS II revealed that the yield reduction spread basipetally via the veins through the leaf at a speed of 1.6 ± 0.3 mm s−1 while the propagation speed in the intervein region was c. 50 times slower. Propagation of the signal through the veins was confirmed because PS I, which is present in the bundle sheath cells around the leaf vessels, was affected first. Hence, spreading of the signal along the veins represents a path with higher travelling speed than within the intervein region of the leaf lamina. Upon the electrical signal, cytoplasmic pH decreased transiently from 7.0 to 6.4, while apoplastic pH increased transiently from 4.5 to 5.2. Moreover, photochemical quantum yield of isolated chloroplasts was strongly affected by pH changes in the surrounding medium, indicating a putative direct influence of electrical signalling via changes of cytosolic pH on leaf photosynthesis. 相似文献
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ALESSANDRA FIDELIS GERHARD E. OVERBECK VALÉRIO D. PILLAR JÖRG PFADENHAUER 《Austral ecology》2009,34(5):558-566
The role of facilitation in the structuring of plant communities has been often demonstrated in environments under high abiotic stress, especially in semi‐arid and arid ecosystems and high elevations. Few studies, however, analysed facilitation in systems that are highly productive and rich in species, which are thought to be theoretically unlikely to demonstrate strong effects of facilitation. Here, we investigate the importance of Eryngium horridum, a rosette species, on the maintenance of plant diversity in subtropical grasslands in southern Brazil. We evaluated facilitation in areas under two different types of management: abandonment and grazing. Plots were established in areas with and without individuals of E. horridum and all species were identified and had their cover estimated. The Relative Neighbour Effect index was calculated in order to verify the presence of competition or facilitation. Our results indicated facilitation in both abandoned and in grazed grasslands, but apparently through different mechanisms. In the first case, the plant's architecture opens the canopy and allows more light to reach small forbs in the grass matrix. In the second case, E. horridum appears to protect more palatable species from herbivores. Otherwise considered an obnoxious species, E. horridum plays an important ecological role in subtropical grasslands in southern Brazil by facilitating other species and consequently, increasing local richness. Areas with this rosette species are important sources of diaspores, which are able to colonize new open sites and thus, maintain biodiversity. 相似文献
108.
VANSELOW KLAUS HEINRICH; KOLBOWSKI J?RG; HANSEN ULF-PETER 《Journal of experimental botany》1989,40(2):247-256
Linearization is an efficient means of detecting individualcomponents in complex fluorescence induction curves. In a previousinvestigation based on sine-waves (Hansen, Kolbowski, and Dau,1987) the components related to the plastoquinone pool, thehigh-energy state of the thylakoid membrane and the state 1-state2 transition controller could be identified. In this paper,binary noise is used as an alternative input signal which canalso allow linearization by mathematical tools. Comparison withexperiments using sine-waves shows that curve-fitting of thenoise experiments yields the same data as the sine-wave analysis.Further, some additional components were revealed as labelledby the related time-constants whose values depended on lightintensity (e.g. 5, 15, 20, 70, 85, 550 s for spinach at 2.5W m2). The advantages of noise analysis are a shorter measuring time and the availability ofan on-line criterion which indicates when a sufficient signal-to-noiseratio is reached. Key words: Chlorophyll fluorescence, correlation functions, linearization, noise, spinach, time-constants 相似文献
109.
QIN LENG JÜRG SCHÖNENBERGER ELSE MARIE FRIIS fmls 《Botanical journal of the Linnean Society. Linnean Society of London》2005,148(4):377-407
Eight new species in seven new genera of follicular fruits are described from the Late Cretaceous of southern Sweden. They are Agapitocarpus emisxus , Chontrocarpus pachytoichus , Maiandrocarpus moirasmenus , Malliocarpus batrachoides , Mitocarpus elegans , Xylocarpus rhitidoides , Zeugarocarpus adroagathus and Z. leptoagathus . The fossil follicles are borne along infructescence axes or more commonly occur as isolated, dispersed fruits. Three genera, Maiandrocarpus , Mitocarpus and Zeugarocarpus , have follicles in distinct pairs borne spirally on an infructescence axis. Each follicle of a pair faces the axis with its ventral slit, which strongly indicates that the paired follicles were derived from two separate, monocarpellate flowers rather than from a single, bicarpellate flower. One genus ( Malliocarpus ) has follicles borne individually in the infructescence and three others ( Agapitocarpus , Chontrocarpus and Xylocarpus ) are known only as dispersed follicles. The paired follicles share many features with most of the dispersed follicles, including a sessile stigmatic area, a three-layered simple follicle wall, a simple vascular system composed of one dorsal and two lateral bundles, as well as a marginal-linear placentation bearing several anatropous ovules. Accordingly they are thought to belong to the same complex of taxa. The general structure of the fossils and comparison with modern angiosperms suggest that the fossils might represent an extinct lineage within or close to basal eudicots and many characters are shared with members of extant Proteaceae. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 377–407. 相似文献
110.
The Leapfrog Group, a consortium of more than 100 large employers, purchasing coalitions, and states that collectively provide health insurance to more than 33 million people, convened in 2000 with the goal of using market forces to improve the quality of healthcare. The resulting Leapfrog initiative suggested selective referral of complex procedures to high-volume hospitals and set volume thresholds for five procedures. This was based on the hypothesis that low-volume hospitals have higher mortality, which can be viewed in simplified statistical terms as the hypothesis that the binomial p is a decreasing function of n. The analysis of the correlation between hospitals' standardized mortality ratios (SMR, i.e., the ratio of observed to expected deaths) and hospitals' procedural volumes is revealing about the volume/mortality hypothesis. This presents an unusual pedagogic example in which the detection of correlation in the presence of nonlinear dependence is of primary interest, and thus the Pearson correlation is ideally suited. The frequently preferred nonparametric measures of bivariate association are inappropriate as they are unable to discriminate between correlation and dependence. 相似文献