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71.
JC Barbero-Alvarez JV Subiela J Granda-Vera C Castagna M Gómez J Del Coso 《Biology of sport / Institute of Sport》2015,32(4):339-344
Despite its growing popularity, few studies have investigated specific physiological demands for elite female futsal. The aim of this study was to determine aerobic fitness in elite female futsal players using laboratory and field testing. Fourteen female futsal players from the Venezuelan National team (age =21.2±4.0 years; body mass =58.6±5.6 kg; height =161±5.0 cm) performed a progressive maximal treadmill test under laboratory conditions. Players also performed a progressive intermittent futsal-specific field test for endurance, the Futsal Intermittent Endurance Test (FIET), until volitional fatigue. Outcome variables were exercise heart rate (HR), VO2, post-exercise blood lactate concentrations ([La]b) and running speeds (km · h-1). During the treadmill test, VO2max, maximal aerobic speed (MAS), HR and peak [La]b were 45.3±5.6 ml · kg-1 · min-1, 12.5±1.77 km · h-1, 197±8 beats · min-1 and 11.3±1.4 mmol · l-1, respectively. The FIET total distance, peak running velocity, peak HR and [La]b were 1125.0±121.0 m, 15.2±0.5 km · h-1, 199±8 beats · min-1 and 12.5±2.2 mmol · l-1, respectively. The FIET distance and peak speed were strongly associated (r= 0.85-87, p < 0.0001) with VO2max and MAS, respectively. Peak HR and [La]b were not significantly different between tests. Elite female futsal players possess moderate aerobic fitness. Furthermore, the FIET can be considered as a valid field test to determine aerobic fitness in elite level female futsal players. 相似文献
72.
DNA hybridization evidence for the principal lineages of hummingbirds (Aves:Trochilidae) 总被引:3,自引:0,他引:3
The spectacular evolutionary radiation of hummingbirds (Trochilidae) has
served as a model system for many biological studies. To begin to provide a
historical context for these investigations, we generated a complete matrix
of DNA hybridization distances among 26 hummingbirds and an outgroup swift
(Chaetura pelagica) to determine the principal hummingbird lineages. FITCH
topologies estimated from symmetrized delta TmH-C values and subjected to
various validation methods (bootstrapping, weighted jackknifing, branch
length significance) indicated a fundamental split between hermit
(Eutoxeres aquila, Threnetes ruckeri; Phaethornithinae) and nonhermit
(Trochilinae) hummingbirds, and provided strong support for six principal
nonhermit clades with the following branching order: (1) a predominantly
lowland group comprising caribs (Eulampis holosericeus) and relatives
(Androdon aequatorialis and Heliothryx barroti) with violet-ears (Colibri
coruscans) and relatives (Doryfera ludovicae); (2) an Andean-associated
clade of highly polytypic taxa (Eriocnemis, Heliodoxa, and Coeligena); (3)
a second endemic Andean clade (Oreotrochilus chimborazo, Aglaiocercus
coelestis, and Lesbia victoriae) paired with thorntails (Popelairia
conversii); (4) emeralds and relatives (Chlorostilbon mellisugus, Amazilia
tzacatl, Thalurania colombica, Orthorhyncus cristatus and Campylopterus
villaviscensio); (5) mountain-gems (Lampornis clemenciae and Eugenes
fulgens); and (6) tiny bee-like forms (Archilochus colubris, Myrtis fanny,
Acestrura mulsant, and Philodice mitchellii). Corresponding analyses on a
matrix of unsymmetrized delta values gave similar support for these
relationships except that the branching order of the two Andean clades (2,
3 above) was unresolved. In general, subsidiary relationships were
consistent and well supported by both matrices, sometimes revealing
surprising associations between forms that differ dramatically in plumage
and bill morphology. Our results also reveal some basic aspects of
hummingbird ecologic and morphologic evolution. For example, most of the
diverse endemic Andean assemblage apparently comprises two genetically
divergent clades, whereas the majority of North American hummingbirds
belong a single third clade. Genetic distances separating some
morphologically distinct genera (Oreotrochilus, Aglaiocercus, Lesbia;
Myrtis, Acestrura, Philodice) were no greater than among congeneric
(Coeligena) species, indicating that, in hummingbirds, morphological
divergence does not necessarily reflect level of genetic divergence.
相似文献
73.
74.
Loss of phylogenetic information in chorion gene families of Bombyx mori gene conversion 总被引:1,自引:0,他引:1
Regier JC; Weigmann BM; Leclerc RF; Friedlander TP 《Molecular biology and evolution》1994,11(1):72-87
The silkmoth chorion has provided a stimulating model for the study of
evolution and developmental regulation of gene families. Previous attempts
at inferring relationships among chorion sequences have been based on
pairwise comparisons of overall similarity, a potentially problematic
approach. To remedy this, we identified the alignable regions of low
sequence variability and then analyzed this restricted database by
parsimony and neighbor-joining methods. At the deepest level, the chorion
sequence tree is split into two branches, called "alpha" and "beta." Within
each branch, early- and late-expressing genes each constitute monophyletic
groups, while the situation with middle-expressing genes remains uncertain.
The HcB gene family appears to be the most basal beta-branch group, but
this conclusion is qualified because the effect of gene conversion on
branching order is unknown. Previous studies by Eickbush and colleagues
have strongly suggested that ErA, HcA, and HcB families undergo gene
conversion within a gene family, whereas the ErB family does not. The
occurrence of conversion correlates with a particular tree structure;
namely, branch lengths are much greater at the base of the family than at
higher internodes and terminal branches. These observations raise the
possibility that chorion gene families are defined by gene conversion
events (reticulate evolution) rather than by descent with modification
(synapomorphy).
相似文献
75.
76.
Water quality and algal populations in the Vaal River Barrage Reservoir have been monitored extensively for many decades, because of its importance as a water source for the most densely populated area in South Africa. Although Aulacoseira granulata (Ehrenberg) Simonsen is frequently found and at it times dominates algal assemblages in the Barrage, Aulacoseira ambigua (F.Meister) Tuji & D.M.Williams has never before been recorded at this locality. During a countrywide proficiency-testing scheme for algae counting, coordinated by Rand Water, spiral-shaped diatom colonies with distinctly curved cells were detected during May 2015. Upon investigation, it was found that the spiral colonies were Aulacoseira ambigua f. japonica, its presence in the fresh waters of South Africa being recorded for the first time. Since their first appearance during May 2015, colonies of Aulacoseira ambigua f. japonica have been constantly present in the surface waters of the Barrage. Their presence at this site can be linked to increasing eutrophication in the Vaal River, because the spiral form is known to prefer eutrophic conditions. Centric diatoms rarely form spiral colonies and there is some confusion in the literature as to the identity of this particular form, therefore in this paper we discuss this taxon, its nomenclature and ecological significance. 相似文献
77.
Jin-Oh You Dariela Almeda George JC Ye Debra T Auguste 《Journal of biological engineering》2010,4(1):15
For years, the field of drug delivery has focused on (1) controlling the release of a therapeutic and (2) targeting the therapeutic
to a specific cell type. These research endeavors have concentrated mainly on the development of new degradable polymers and
molecule-labeled drug delivery vehicles. Recent interest in biomaterials that respond to their environment have opened new
methods to trigger the release of drugs and localize the therapeutic within a particular site. These novel biomaterials, usually
termed "smart" or "intelligent", are able to deliver a therapeutic agent based on either environmental cues or a remote stimulus.
Stimuli-responsive materials could potentially elicit a therapeutically effective dose without adverse side effects. Polymers
responding to different stimuli, such as pH, light, temperature, ultrasound, magnetism, or biomolecules have been investigated
as potential drug delivery vehicles. This review describes the most recent advances in "smart" drug delivery systems that
respond to one or multiple stimuli. 相似文献
78.
Laurie L Baker Rodrigo Wiff JC Quiroz Andrés Flores Renato Céspedes Mauricio A. Barrientos Vilma Ojeda Claudio Gatica 《Environmental Biology of Fishes》2014,97(10):1083-1093
The pink cusk-eel (Genypterus blacodes), a benthic-demersal fish confined to the southern hemisphere, supports an important commercial fishery in Chile where it is exploited over an extensive geographic area. Although the fishery was originally divided into a northern (41º28′–47º00′S) and southern (47º00′–57º00′S) zone for the purposes of fisheries management, recent studies have reported significant differences in life history parameters between these zones. Individuals from the southern zone reached larger asymptotic sizes and possessed higher survival rates compared to the northern zone. We estimate and compare the gonadosomatic index (GSI), shape of the maturity ogive, and length at 50 % maturity (L 50%) of female G. blacodes between management zones and across time using biological data collected from the industrial fleet between 1985 and 2009. Females in the northern zone had higher monthly mean GSI than females in the southern zone. Our analyses also revealed L 50% to be significantly higher in the southern zone than in the northern zone from 1985 to 2009. The significant differences in life-history traits between fishery management zones agree with the trade-offs predicted by Charnov’s life history theory. Together these results provide additional support for the hypothesis that two separate stocks exist and suggest that females from the northern zone have developed a life-history strategy, which favours early maturation and a proportionally greater investment in reproduction than females from the southern zone. 相似文献
79.
Frédéric D Chevalier Claudia LL Valentim Philip T LoVerde Timothy JC Anderson 《BMC genomics》2014,15(1)
Background
Identification of parasite genes that underlie traits such as drug resistance and host specificity is challenging using classical linkage mapping approaches. Extreme QTL (X-QTL) methods, originally developed by rodent malaria and yeast researchers, promise to increase the power and simplify logistics of linkage mapping in experimental crosses of schistosomes (or other helminth parasites), because many 1000s of progeny can be analysed, phenotyping is not required, and progeny pools rather than individuals are genotyped. We explored the utility of this method for mapping a drug resistance gene in the human parasitic fluke Schistosoma mansoni.Results
We staged a genetic cross between oxamniquine sensitive and resistant parasites, then between two F1 progeny, to generate multiple F2 progeny. One group of F2s infecting hamsters was treated with oxamniquine, while a second group was left untreated. We used exome capture to reduce the size of the genome (from 363 Mb to 15 Mb) and exomes from pooled F2 progeny (treated males, untreated males, treated females, untreated females) and the two parent parasites were sequenced to high read depth (mean = 95-366×) and allele frequencies at 14,489 variants compared. We observed dramatic enrichment of alleles from the resistant parent in a small region of chromosome 6 in drug-treated male and female pools (combined analysis: = 11.07, p = 8.74 × 10-29). This region contains Smp_089320 a gene encoding a sulfotransferase recently implicated in oxamniquine resistance using classical linkage mapping methods.Conclusions
These results (a) demonstrate the utility of exome capture for generating reduced representation libraries in Schistosoma mansoni, and (b) provide proof-of-principle that X-QTL methods can be successfully applied to an important human helminth. The combination of these methods will simplify linkage analysis of biomedically or biologically important traits in this parasite.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-617) contains supplementary material, which is available to authorized users. 相似文献80.
Rapid screening for phenotype-genotype associations by linear transformations of genomic evaluations
Jose L Gualdrón Duarte Rodolfo JC Cantet Ronald O Bates Catherine W Ernst Nancy E Raney Juan P Steibel 《BMC bioinformatics》2014,15(1)