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Coral Falco Octavio Alvarez Isabel Castillo Isaac Estevan Julio Martos Fernando Mugarra Antonio Iradi 《Journal of biomechanics》2009,42(3):242-248
Taekwondo, originally a Korean martial art, is well known for its kicks. One of the most frequently used kicks in competition is Bandal Chagui or roundhouse kick. Excellence in Taekwondo relies on the ability to make contact with the opponent's trunk or face with enough force in as little time as possible, while at the same time avoiding being hit. Thus, the distance between contestants is an important variable to be taken into consideration. Thirty-one Taekwondo athletes in two different groups (expert and novice, according to experience in competition) took part in this study. The purpose of this study was to examine both impact force and execution time in a Bandal Chagui or roundhouse kick, and to explore the effect of execution distance in these two variables. A new model was developed in order to measure the force exerted by the body on a load. A force platform and a contact platform were used to measure these variables. The results showed that there are no significant differences in terms of impact force in relation to execution distance in expert competitors. Significant and positive correlations between body mass and impact force (p<.01) seem to mean that novice competitors use their body mass to generate high impact forces. Significant differences were found in competitive experience and execution time for the three different distances of kicking considered in the study. Standing at a certain further distance from the opponent should be an advantage for competitors who are used to kick from a further distance in their training. 相似文献
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Carme Saurina Marc Saez Rafael Marcos-Gragera Maria Antònia Barceló Gemma Renart Carmen Martos 《Cancer epidemiology》2010,34(2):109-115
Objective: To assess the association between the incidence of larynx cancer and socioeconomic conditions in the province of Girona from a spatial viewpoint. Materials and methods: Incidence cases of larynx cancer (CL) in 1994–2004 were provided by the Girona Cancer Registry. A census tract (CT) was assigned to all patients. Socioeconomic data were extracted from the 2001 Census. A deprivation index for each CT was obtained by principal component analysis, using four socioeconomic indicators. The standardised incidence ratio (SIR) was calculated using the CL incidence rates in the men of the province of Girona assuming a Poisson distribution. Relative risk was obtained applying the Besag, York and Mollié model. The deprivation index was introduced into the model and was categorised in quartiles. Results: Four hundred and seventy-six incident cases in men were registered. CTs in the lowest deprivation index had a lower risk of larynx cancer, with a risk increase in the higher quartiles. In the highest quartile it was 1.91 times greater than in the lowest. This association was significant when the whole province was considered. Discussion: The deprivation index explains only part of the geographical variability of CL incidence. Other risk factors without spatial structure may contribute to this explaination. 相似文献
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Nikolay Vassilev Bettina Eichler-Löbermann Antonia Reyes Requena Vanessa Martos Ana Lopez Maria Vassileva 《Reviews in Environmental Science and Biotechnology》2016,15(4):627-638
Biodiesel derived from renewable biological sources has in recent years emerged as an alternative fuel for transportation sector. Similarly, glycerol, the main co-product of biodiesel production, has received considerable attention as feedstock for producing various value added products including biofertilizers. The aim of this review is to highlight the value-added utilization of glycerol as a substrate in fermentation processes for P-solubilization by free and immobilized cells and as a formulation agent in preparation of commercial products. In the majority of cases, glycerol demonstrates multiple traits and, therefore some routine techniques for P-solubilization when based on glycerol can be attractive from technical and economic point of view. 相似文献
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Parameters of exercise physiology were studied in nearly 300 subjects to resolve whether these indices were equally suitable under laboratory and field conditions to assess the level of physical fitness and optimum work load. Respiratory gas exchange, heart rate and exercise acidosis parameters were studied. The inference drawn on the basis of the obtained data has been that both the mode and the intensity of the imposed exercise exert significant influence on the variation of physiological parameters. During running either on the treadmill or in the field test, blood lactate levels were comparable, but performances related to these concentrations were not the same. When different modes of exercise were employed, also lactate levels differed between the laboratory and field studies. The performance of patients under or after exercise rehabilitation following acute myocardial infarction by using instrumental monitoring in the laboratory was found to excel that attained during rehabilitation exercise training. Any change in the level of physical fitness can only be reliably followed when physiological parameters are obtained with the same mode of exercise and intensity under the same environmental conditions. Modern training planning of sports and exercise should take into account the data derived from both the laboratory and the field studies concerning cardiorespiratory system and metabolism. 相似文献
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Vilmar Veldre Kessy Abarenkov Mohammad Bahram Florent Martos Marc-Andre Selosse Heidi Tamm Urmas Kõljalg Leho Tedersoo 《Fungal Ecology》2013,6(4):256-268
Fungi from the Ceratobasidiaceae family have important ecological roles as pathogens, saprotrophs, non-mycorrhizal endophytes, orchid mycorrhizal and ectomycorrhizal symbionts, but little is known about the distribution and evolution of these nutritional modes. All public ITS sequences of Ceratobasidiaceae were downloaded from databases, annotated with ecological and taxonomic metadata, and tested for the non-random phylogenetic distribution of nutritional modes. Phylogenetic analysis revealed six main clades within Ceratobasidiaceae and a poor correlation between molecular phylogeny and morphological–cytological characters traditionally used for taxonomy. Sequences derived from soil (representing putative saprotrophs) and orchid mycorrhiza clustered together, but remained distinct from pathogens. All nutritional modes were phylogenetically conserved in the Ceratobasidiaceae based on at least one index. Our analyses suggest that in general, autotrophic orchids form root symbiosis with available Ceratobasidiaceae isolates in soil. Ectomycorrhiza-forming capability has evolved twice within the Ceratobasidiaceae and it had a strong influence on the evolution of mycoheterotrophy and host specificity in certain orchid taxa. 相似文献
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Déquard-Chablat M Sellem CH Golik P Bidard F Martos A Bietenhader M di Rago JP Sainsard-Chanet A Hermann-Le Denmat S Contamine V 《Molecular biology and evolution》2011,28(7):2063-2075
An F(1)F(O) ATP synthase in the inner mitochondrial membrane catalyzes the late steps of ATP production via the process of oxidative phosphorylation. A small protein subunit (subunit c or ATP9) of this enzyme shows a substantial genetic diversity, and its gene can be found in both the mitochondrion and/or nucleus. In a representative set of 26 species of fungi for which the genomes have been entirely sequenced, we found five Atp9 gene repartitions. The phylogenetic distribution of nuclear and mitochondrial Atp9 genes suggests that their evolution has included two independent transfers to the nucleus followed by several independent episodes of the loss of the mitochondrial and/or nuclear gene. Interestingly, we found that in Podospora anserina, subunit c is exclusively produced from two nuclear genes (PaAtp9-5 and PaAtp9-7), which display different expression profiles through the life cycle of the fungus. The PaAtp9-5 gene is specifically and strongly expressed in germinating ascospores, whereas PaAtp9-7 is mostly transcribed during sexual reproduction. Consistent with these observations, deletion of PaAtp9-5 is lethal, whereas PaAtp9-7 deletion strongly impairs ascospore production. The P. anserina PaAtp9-5 and PaAtp9-7 genes are therefore nonredundant. By swapping the 5' and 3' flanking regions between genes we demonstrated, however, that the PaAtp9 coding sequences are functionally interchangeable. These findings show that after transfer to the nucleus, the subunit c gene in Podospora became a key target for the modulation of cellular energy metabolism according to the requirements of the life cycle. 相似文献