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101.
D Deprez J Fransen M Lenoir RM Philippaerts R Vaeyens 《Biology of sport / Institute of Sport》2015,32(1):65-70
The aim of the study was to investigate test reliability of the Yo-Yo intermittent recovery test level 1 (YYIR1) in 36 high-level youth soccer players, aged between 13 and 18 years. Players were divided into three age groups (U15, U17 and U19) and completed three YYIR1 in three consecutive weeks. Pairwise comparisons were used to investigate test reliability (for distances and heart rate responses) using technical error (TE), coefficient of variation (CV), intra-class correlation (ICC) and limits of agreement (LOA) with Bland-Altman plots. The mean YYIR1 distances for the U15, U17 and U19 groups were 2024 ± 470 m, 2404 ± 347 m and 2547 ± 337 m, respectively. The results revealed that the TEs varied between 74 and 172 m, CVs between 3.0 and 7.5%, and ICCs between 0.87 and 0.95 across all age groups for the YYIR1 distance. For heart rate responses, the TEs varied between 1 and 6 bpm, CVs between 0.7 and 4.8%, and ICCs between 0.73 and 0.97. The small ratio LOA revealed that any two YYIR1 performances in one week will not differ by more than 9 to 28% due to measurement error. In summary, the YYIR1 performance and the physiological responses have proven to be highly reliable in a sample of Belgian high-level youth soccer players, aged between 13 and 18 years. The demonstrated high level of intermittent endurance capacity in all age groups may be used for comparison of other prospective young soccer players. 相似文献
102.
Lactobacillus buchneri is probably the most beneficial microorganism for efficient preservation of animal feed silages made from grass, maize and other plant material against aerobic spoilage. Its obligatory heterofermentative nature, acid resistance and robustness have drawn attention to this species for applications as silage starter culture as well as for genetic engineering. For the first time, two cryptic plasmids present in the same L. buchneri strain, L. buchneri CD034, were isolated, sequenced and characterized. The larger plasmid, designated pCD034-1 was found to be 3424 bp in length with a G + C content of 38.36%. The smaller plasmid, designated pCD034-2 was found to be 2707 bp in length with a G + C content of 38.60%. On both plasmids we predicted three open reading frames. On pCD034-1, ORF 1 encodes a putative replication protein which shares 99% identity with the RepA protein of a Lactobacillus plantarum derived pC194/pUB110-family plasmid. ORF 2 encodes a putative protein of unknown function. ORF 1 and ORF 2 of pCD034-2 correspond to RepA and RepB proteins similar to those of plasmid pLB4 from L. plantarum. ORF 3 of both plasmids encodes a putative mobilization protein similar to that of the pediococcal plasmid pF8801. Double strand origins, putative single strand origins and typical mobilization start signals were identified. Both plasmids were shown to be maintained at relatively high plasmid copy numbers. Two shuttle vectors carrying the origins of replication of pCD034-1 and pCD034-2 were constructed and used to successfully transform two other species isolated from the same environment. Hence, we consider the two novel L. buchneri plasmids a valuable resource for the generation of shuttle and expression vectors for LAB. 相似文献
103.
Kjellman BM Fredrikson M Glad-Mattsson G Sjöberg F Huss FR 《Annals of surgical innovation and research》2011,5(1):4-8
Background
Hypothermia in burns is common and increases morbidity and mortality. Several methods are available to reach and maintain normal core body temperature, but have not yet been evaluated in critical care for burned patients. Our unit's ordinary technique for controlling body temperature (Bair Hugger®+ radiator ceiling + bed warmer + Hotline®) has many drawbacks e.g.; slow and the working environment is hampered. The aim of this study was to compare our ordinary heating technique with newly-developed methods: the Allon?2001 Thermowrap (a temperature regulating water-mattress), and Warmcloud (a temperature regulating air-mattress).Methods
Ten consecutive burned patients (> 20% total burned surface area and a core temperature < 36.0°C) were included in this prospective, randomised, comparative study. Patients were randomly exposed to 3 heating methods. Each treatment/measuring-cycle lasted for 6 hours. Each heating method was assessed for 2 hours according to a randomised timetable. Core temperature was measured using an indwelling (bladder) thermistor. Paired t-tests were used to assess the significance of differences between the treatments within the patients. ANOVA was used to assess the differences in temperature from the first to the last measurement among all treatments. Three-way ANOVA with the Tukey HSD post hoc test and a repeated measures ANOVA was used in the same manner, but included information about patients and treatment/measuring-cycles to control for potential confounding. Data are presented as mean (SD) and (range). Probabilities of less than 0.05 were accepted as significant.Results
The mean increase, 1.4 (SD 0.6°C; range 0.6-2.6°C) in core temperature/treatment/measuring-cycle highly significantly favoured the Allon?2001 Thermowrap in contrast to the conventional method 0.2 (0.6)°C (range -1.2 to 1.5°C) and the Warmcloud 0.3 (0.4)°C (range -0.4 to 0.9°C). The procedures for using the Allon?2001 Thermowrap were experienced to be more comfortable and straightforward than the conventional method or the Warmcloud.Conclusions
The Allon?2001 Thermowrap was more effective than the Warmcloud or the conventional method in controlling patients' temperatures. 相似文献104.
105.
Florian Krammer Theresa Schinko Dieter Palmberger Christopher Tauer Paul Messner Reingard Grabherr 《Molecular biotechnology》2010,45(3):226-234
Virus-like particles (VLPs) consisting of the influenza A virus proteins haemagglutinin (HA) and matrix protein (M1) represent
a new alternative approach for vaccine design against influenza virus. Influenza VLPs can be fast and easily produced in sufficient
amounts in insect cells using the baculovirus expression system. Up to now, influenza VLPs have been produced in the Spodoptera frugiperda cell line Sf9. We compared VLP production in terms of yield and quality in two insect cell lines, namely Sf9 and the Trichoplusia ni cell line BTI-TN5B1-4 (High FiveTM). Additionally we compared VLP production with three different HAs and two different M1s from influenza H1 and H3 strains
including one swine-origin pandemic H1N1 strain. Comparison of the two cell lines showed dramatic differences in baculovirus
background as well as in yield and particle density. Taken together, we consider the establishment of the BTI-TN5B1-4 cell
line advantageous as production cell line for influenza VLPs. 相似文献
106.
An RGD-containing peptide, comprising 23 amino acids from the foot-and-mouth disease virus (FMDV) VP1 protein was engineered into the envelope of Autographa californica nuclear polyhedrosis virus surface (AcNPV) using two different display strategies. The RGD-motif is a well-described tripeptide, that by binding to cell surface integrins facilitates virus entry into cells. This epitope was displayed, either by directly modifying the native major envelope protein gp64 of AcNPV, or by incorporating a second, modified version of gp64 onto the virus surface. Transduction efficiencies of four mammalian cell lines were compared by detecting the expression of the reporter gene green fluorescent protein (gfp), delivered by the baculovirus genome. Our results showed that insertion of the RGD-peptide into the envelope protein gp64 leads to enhanced specific uptake of baculoviral particles in mammalian cells, only when a combination of wild-type and mutant gp64 was present on the viral surface. Whenever the RGD-peptide was directly inserted into the native gp64, the overall amount of gp64 envelope protein was diminished, leading to decreased viral uptake. 相似文献
107.
With the cancellation of fenamiphos in the near future, alternative nematode management tactics for plant-parasitic nematodes (PPN) on golf courses need to be identified. The use of entomopathogenic nematodes (EPN) has been suggested as one possible alternative. This paper presents the results of 10 experiments evaluating the efficacy of EPN at managing PPN on turfgrasses and improving turf performance. These experiments were conducted at various locations throughout Florida over the course of a decade. In different experiments, different EPN species were tested against different species of PPN. Separate experiments evaluated multiple rates and applications of EPN, compared different EPN species, and compared single EPN species against multiple species of PPN. In a few trials, EPN were associated with reductions in certain plant-parasite species, but in other trials were associated with increases. In most trials, EPN had no effect on plant parasites. Because EPN were so inconsistent in their results, we conclude that EPN are not acceptable alternatives to fenamiphos by most turf managers in Florida at this time. 相似文献
108.
Using inbreeding theory as applied to neutral alleles inherited maternally,
we generate expected probability distributions of times to identity by
descent for random pairs of mitochondrial genotypes within a population or
within an entire species characterized by high gene flow. For comparisons
with these expectations, empirical distributions of times to most recent
common ancestry were calculated (by conventional mtDNA clock calibrations)
from mtDNA haplotype distances observed within each of three vertebrate
species--American eels, hardhead catfish, and redwinged blackbirds. These
species were chosen for analysis because census population size in each is
currently large and because both genetic and life-history data are
consistent with the postulate that historical gene flow within these
species has been high. The observed molecular distances among mtDNA
lineages were two to three orders of magnitude lower than predicted from
census sizes of breeding females, suggesting that rate of mtDNA evolution
is decelerated in these species and/or that long-term effective population
size is vastly smaller than present-day population size. Several
considerations point to the latter possibility as most likely. The genetic
structure of any species is greatly influenced by historical demography;
even for species that are currently abundant, mtDNA gene lineages appear to
have been channeled through fairly small numbers of ancestors.
相似文献
109.
Georg Grabherr 《Plant Ecology》1980,41(2):111-120
Summary Variation in the dwarf shrub community Loiseleurio-Cetrarietum from Mt. Patscherkofel, Austria, was investigated using polar ordination, principal component analysis, hierarchical cluster analysis, and multiple correlation analysis. Comparison was made with existing data (relevé tables) from the Alps. In addition to phytosociological methods the canopy structure and the morphological variability of the dominant species Loiseleuria procumbens were studied. The result of the namerical phytosociological analyses yield 3 clusters representing: 1) A dense Loiseleuria carpet, 2) a Loiseleuria carpet damaged by erosion and 3) an open Loiseleuria community on skeletal soils. The first two communities can be combined as one type because of their canopy structure in the form of dense intertwined individual plants and because of the morphological uniformity of Loiseleuria, although in the second group there are species growing on erosion gaps and showing close floristic connections to the third group. The comparison of 140 relevés from the Alps proves that the Loiseleurio-Cetrarietum is characterized only by the dominance of Loiseleuria procumbens while the abundantly occurring lichens change in their species composition along the gradient of wind, and elevation. The open Loiseleuria community at the most extreme habitats (cluster 3) is regarded as a new association. Not only floristic but also physiognomical, morphological and ecophysiological evidence led to this conclusion. The name Gymnomitrio-Loiseleurietum (ass. prov.) is proposed. This plant community shows floristic and ecological correlations to the Diapensia-Loiseleuria-Cesiolichen community known from Scandinavia.Nomenclature of species follows Ehrendorfer (1973) (vascular plants), Poelt (1974) (lichens) and Gams (1973) (mosses).For PCA, hierarchical cluster analysis, and multiple correlation analysis, computer programs from the data bank system (AFO-data) of the Alpine Forschungsstelle Obergurgl, Austria were used. I am indebted to Dr. S. Pamer and P. Moser for their invaluable help. For polar ordination a separate program was developed (language: Simula, author: Dr. G. Knecht). I am also indebted to Dr. H. Hilscher for the translation of the text. 相似文献
110.
G. Grabherr 《Plant Ecology》1982,48(3):209-217
The long term effect of tourist trampling on a high altitudinal grassland (Caricion curvulae) in the Tyrolean Alps was investigated.Even under slight trampling the frequency of sensitive species decreases. The most sensitive species were found to be fruticose lichens, followed by mosses, some forbs and broadleaved grasses. Tolerant to trampling are the dominant species Carex curvula, and Ligusticum mutellina, which do not disappear completely even at a tourist frequency of 150 tourists per metre per day. Trampling increases soil bulk density moderately but has no marked effect on the soil water content.Comparison with high alpine sedge heath vegetation in North America shows a surprising uniformity of this vegetation type in response to trampling and also indicates that the common generalisation that alpine ecosystems are fragile and sensitive to disturbance does not hold true in this context. Furthermore these results represent evidence against the theory that ecosystems with low diversity are much more sensitive to arteficial impact than ecosystems with high diversity. However, if even the most resistant plants which are the dominant sedges are destroyed completely the rate of recovery is very low and may last for a long time. In the case of Carex curvula this is supported by the fact that it has very low seed production and grows mainly vegetatively. The rate of spread of the rhizome system of this species is 8 mm in 10 years. Similar figures may apply for the sedge species dominating in the alpine vegetation of North America. Thus fragility of this vegetation in regard to trampling does not mean low tolerance but low regeneration.Nomenclature of species follows Ehrendorfer (1973) for vascular plants and Poelt (1974) for lichens.The PCA calculations were done at the Computer laboratory of the University of Wales during a post doctoral stay at the School of Plant Biology in Bangor, U.K. I would like to record my thanks to Prof. Dr. P. Greig-Smith for fruitful discussions and reading the draft. 相似文献