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181.
While the importance of physical abilities and motor coordination is non-contested in sport, more focus has recently been turned toward cognitive processes important for different sports. However, this line of studies has often investigated sport-specific cognitive traits, while few studies have focused on general cognitive traits. We explored if measures of general executive functions can predict the success of a soccer player. The present study used standardized neuropsychological assessment tools assessing players' general executive functions including on-line multi-processing such as creativity, response inhibition, and cognitive flexibility. In a first cross-sectional part of the study we compared the results between High Division players (HD), Lower Division players (LD) and a standardized norm group. The result shows that both HD and LD players had significantly better measures of executive functions in comparison to the norm group for both men and women. Moreover, the HD players outperformed the LD players in these tests. In the second prospective part of the study, a partial correlation test showed a significant correlation between the result from the executive test and the numbers of goals and assists the players had scored two seasons later. The results from this study strongly suggest that results in cognitive function tests predict the success of ball sport players. 相似文献
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184.
Minttumaaria Hannonen & Liselotte Sundström 《Ethology : formerly Zeitschrift fur Tierpsychologie》2002,108(11):961-973
Understanding the determinants of reproductive skew (the partitioning of reproduction among co‐breeding individuals) is one of the major questions in social evolution. In ants, multiple‐queen nests are common and reproductive skew among queens has been shown to vary tremendously both within and between species. Proximate determinants of skew may be related to both queen and worker behaviour. Queens may attempt to change their reproductive share through dominance interactions, egg eating and by changing individual fecundity. Conversely, workers are in a position to regulate the reproductive output of queens when rearing the brood. This paper investigates queen behaviour at the onset of egg laying and the effect of queen fecundity and worker behaviour on brood development and reproductive shares of multiple queens in the ant Formica fusca. The study was conducted in two‐queen laboratory colonies where the queens produced only worker offspring. The results show that in this species reproductive apportionment among queens is not based on dominance behaviour and aggression, but rather on differences in queen fecundity. We also show that, although the queen fecundity at the onset of brood rearing is a good indicator of her final reproductive output, changes in brood composition occur during brood development. Our results highlight the importance of queen fecundity as a major determinant of her reproductive success. They furthermore suggest that in highly derived polygyne species, such as the Formica ants, direct interactions as a means for gaining reproductive dominance have lost their importance. 相似文献
185.
Liselotte Hardy Vicky Jespers Nassira Dahchour Lambert Mwambarangwe Viateur Musengamana Mario Vaneechoutte Tania Crucitti 《PloS one》2015,10(8)
Bacterial vaginosis (BV), a condition defined by increased vaginal discharge without significant inflammation, is characterized by a change in the bacterial composition of the vagina. Lactobacillus spp., associated with a healthy vaginal microbiome, are outnumbered by BV-associated organisms. These bacteria could form a polymicrobial biofilm which allows them to persist in spite of antibiotic treatment. In this study, we examined the presence of Gardnerella vaginalis and Atopobium vaginae in vaginal biofilms using Peptide Nucleic Acid (PNA) probes targeting these bacteria. For this purpose, we developed three new PNA probes for A. vaginae. The most specific A. vaginae probe, AtoITM1, was selected and then used in an assay with two existing probes, Gard162 and BacUni-1, to evaluate multiplex FISH on clinical samples. Using quantitative polymerase chain reaction (qPCR) as the gold standard, we demonstrated a sensitivity of 66.7% (95% confidence interval: 54.5% - 77.1%) and a specificity of 89.4% (95% confidence interval: 76.1% - 96%) of the new AtoITM1 probe. FISH enabled us to show the presence of a polymicrobial biofilm in bacterial vaginosis, in which Atopobium vaginae is part of a Gardnerella vaginalis-dominated biofilm. We showed that the presence of this biofilm is associated with high bacterial loads of A. vaginae and G. vaginalis. 相似文献
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187.
Liselotte M. Takken Beijersbergen 《Acta zoologica》2017,98(4):340-361
The results of a detailed morphological and pathological study on reindeer bones (Rangifer tarandus) from four medieval hunting stations on Hardangervidda are presented. As intensive marrow collecting left almost no bones intact, traditional sexing methods could only sparsely be applied. Alternative methods had to be explored to successfully assign the fragments to a sex. Employing linear discriminant analysis (LDA) on early‐ and non‐fusing skeletal elements, I have shown that (incomplete) calcanei, metapodia and phalanges I and II can be used successfully to assign a specimen to a sex and should no longer be excluded from osteometric analyses. Differences in the demographic compositions of the taphocoenoses lead to the assumption that hunters in the 11th century AD targeted large reindeer bucks, while at the 13th‐century sites, the complete biocoenose is represented, albeit in a different ratio. There seems to have been a shift in hunting technique: from selective hunting to mass hunting. Size wise, the reindeer from Hardangervidda were smaller than reindeer from contemporary assemblages from the Dovre area (central Norway), a population that is genetically different. Few pathologically affected bones were encountered in the material, but some cases of infections, bone lesions and a progressed osteosarcoma are described. 相似文献
188.
G. Arjen de Groot Carsten Nowak Tomaž Skrbinšek Liselotte W. Andersen Jouni Aspi Luca Fumagalli Raquel Godinho Verena Harms Hugh A.H. Jansman Olof Liberg Francesca Marucco Robert W. Mysłajek Sabina Nowak Małgorzata Pilot Ettore Randi Ilka Reinhardt Wojciech Śmietana Maciej Szewczyk Pierre Taberlet Carles Vilà Violeta Muñoz‐Fuentes 《Mammal Review》2016,46(1):44-59
- Following protection measures implemented since the 1970s, large carnivores are currently increasing in number and returning to areas from which they were absent for decades or even centuries. Monitoring programmes for these species rely extensively on non‐invasive sampling and genotyping. However, attempts to connect results of such studies at larger spatial or temporal scales often suffer from the incompatibility of genetic markers implemented by researchers in different laboratories. This is particularly critical for long‐distance dispersers, revealing the need for harmonized monitoring schemes that would enable the understanding of gene flow and dispersal dynamics.
- Based on a review of genetic studies on grey wolves Canis lupus from Europe, we provide an overview of the genetic markers currently in use, and identify opportunities and hurdles for studies based on continent‐scale datasets.
- Our results highlight an urgent need for harmonization of methods to enable transnational research based on data that have already been collected, and to allow these data to be linked to material collected in the future. We suggest timely standardization of newly developed genotyping approaches, and propose that action is directed towards the establishment of shared single nucleotide polymorphism panels, next‐generation sequencing of microsatellites, a common reference sample collection and an online database for data exchange.
- Enhanced cooperation among genetic researchers dealing with large carnivores in consortia would facilitate streamlining of methods, their faster and wider adoption, and production of results at the large spatial scales that ultimately matter for the conservation of these charismatic species.
189.
Climate Versus In-Lake Processes as Controls on the Development of Community Structure in a Low-Arctic Lake (South-West Greenland) 总被引:3,自引:0,他引:3
N. John Anderson Klaus P. Brodersen David B. Ryves Suzanne McGowan Liselotte S. Johansson Erik Jeppesen Melanie J. Leng 《Ecosystems》2008,11(2):307-324
The dominant processes determining biological structure in lakes at millennial timescales are complex. In this study, we used
a multi-proxy approach to determine the relative importance of in-lake versus indirect processes on the Holocene development
of an oligotrophic lake in SW Greenland (66.99°N, 50.97°W). A 14C and 210Pb-dated sediment core covering approximately 8500 years BP was analyzed for organic–inorganic carbon content, pigments, diatoms,
chironomids, cladocerans, and stable isotopes (δ13C, δ18O). Relationships among the different proxies and a number of independent controlling variables (Holocene temperature, an
isotope-inferred cooling period, and immigration of Betula nana into the catchment) were explored using redundancy analysis (RDA) independent of time. The main ecological trajectories in
the lake biota were captured by ordination first axis sample scores (18–32% variance explained). The importance of the arrival
of Betula (ca. 6500 years BP) into the catchment was indicated by a series of partial-constrained ordinations, uniquely explaining
12–17% of the variance in chironomids and up to 9% in pigments. Climate influences on lake biota were strongest during a short-lived
cooling period (identified by altered stable isotopes) early in the development of the lake when all proxies changed rapidly,
although only chironomids had a unique component (8% in a partial-RDA) explained by the cooling event. Holocene climate explained
less variance than either catchment changes or biotic relationships. The sediment record at this site indicates the importance
of catchment factors for lake development, the complexity of community trends even in relatively simple systems (invertebrates
are the top predators in the lake) and the challenges of deriving palaeoclimate inferences from sediment records in low-Arctic
freshwater lakes. 相似文献
190.
Bhave G Cummings CF Vanacore RM Kumagai-Cresse C Ero-Tolliver IA Rafi M Kang JS Pedchenko V Fessler LI Fessler JH Hudson BG 《Nature chemical biology》2012,8(9):784-790
Collagen IV comprises the predominant protein network of basement membranes, a specialized extracellular matrix, which underlie epithelia and endothelia. These networks assemble through oligomerization and covalent crosslinking to endow mechanical strength and shape cell behavior through interactions with cell-surface receptors. A recently discovered sulfilimine (S=N) bond between a methionine sulfur and hydroxylysine nitrogen reinforces the collagen IV network. We demonstrate that peroxidasin, an enzyme found in basement membranes, catalyzes formation of the sulfilimine bond. Drosophila peroxidasin mutants have disorganized collagen IV networks and torn visceral muscle basement membranes, pointing to a critical role for the enzyme in tissue biogenesis. Peroxidasin generates hypohalous acids as reaction intermediates, suggesting a paradoxically anabolic role for these usually destructive oxidants. This work highlights sulfilimine bond formation as what is to our knowledge the first known physiologic function for peroxidasin, a role for hypohalous oxidants in tissue biogenesis, and a possible role for peroxidasin in inflammatory diseases. 相似文献