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971.
Marco P.C. Marques Kieran Walshe Sean Doyle Pedro Fernandes Carla C.C.R. de Carvalho 《Process Biochemistry》2012,47(3):416-421
The use of high throughput strategies is of acknowledged relevance since the rational use of small-scale reactors, coupled with suitable analytic tools, is contributing to the acceleration of process development in several areas of biotechnology. These small-scale reactors are available in different working volumes and configurations, being useful in a wide array of applications, from cell screening to process optimization.The present work was focused on the development of a high-throughput strategy, combining microtiter plates and analytic methodologies, to screen an in-house library of environmental bacteria in order to identify good siderophore producers. From a library of roughly 500 marine microorganisms, it was possible to ultimately obtain 11 bacterial strains with high production capabilities. Two of them had not been previously identified as siderophore producers. The bioprocess was scaled-up from microtiter plates to a 5 L stirred tank reactor, while maintaining the overall volumetric productivity, using the kLa similarity as scale-up criterion.This novel approach is a suitable alternative to traditional screening tools. 相似文献
972.
Aim The study of geographical discontinuities in the distribution of genetic variability in natural populations is a central topic in both evolutionary and conservation research. In this study, we aimed to analyse (1) the factors associated with genetic diversity at the landscape spatial scale in the highly specialized grasshopper Mioscirtus wagneri and (2) to identify the relative contribution of alternative factors to the observed patterns of genetic structure in this species. Location La Mancha region, Central Spain. Methods We sampled 28 populations of the grasshopper M. wagneri and genotyped 648 individuals at seven microsatellite loci. We employed a causal modelling approach to identify the most influential variables associated with genetic differentiation within a multiple hypothesis‐testing framework. Results We found that genetic diversity differs among populations located in different river basins and decreases with population isolation. Causal modelling analyses showed variability in the relative influence of the studied landscape features across different spatial scales. When a highly isolated population is considered, the analyses suggested that geographical distance is the only factor explaining the genetic differentiation between populations. When that population is excluded, the causal modelling analysis revealed that elevation and river basins are also relevant factors contributing to explaining genetic differentiation between the studied populations. Main conclusions These results indicate that the spatial scale considered and the inclusion of outlier populations may have important consequences on the inferred contribution of alternative landscape factors on the patterns of genetic differentiation even when all populations are expected to similarly respond to landscape structure. Thus, a multiscale perspective should also be incorporated into the landscape genetics framework to avoid biased conclusions derived from the spatial scale analysed and/or the geographical distribution of the studied populations. 相似文献
973.
974.
Sérgio Marta Luís Silva Maria António Castro Pedro Pezarat-Correia Jan Cabri 《Journal of electromyography and kinesiology》2012,22(6):803-813
The aim of the study was to review systematically the literature available on electromyographic (EMG) variables of the golf swing. From the 19 studies found, a high variety of EMG methodologies were reported. With respect to EMG intensity, the right erector spinae seems to be highly activated, especially during the acceleration phase, whereas the oblique abdominal muscles showed moderate to low levels of activation. The pectoralis major, subscapularis and latissimus dorsi muscles of both sides showed their peak activity during the acceleration phase. High muscle activity was found in the forearm muscles, especially in the wrist flexor muscles demonstrating activity levels above the maximal voluntary contraction. In the lower limb higher muscle activity of the trail side was found. There is no consensus on the influence of the golf club used on the neuromuscular patterns described. Furthermore, there is a lack of studies on average golf players, since most studies were executed on professional or low handicap golfers.Further EMG studies are needed, especially on lower limb muscles, to describe golf swing muscle activation patterns and to evaluate timing parameters to characterize neuromuscular patterns responsible for an efficient movement with lowest risk for injury. 相似文献
975.
Marín PJ Santos-Lozano A Santin-Medeiros F Vicente-Rodriguez G Casajús JA Hazell TJ Garatachea N 《Journal of electromyography and kinesiology》2012,22(3):456-462
The current study examined the effects of whole-body vibration (WBV) on upper and lower body muscle activity during static muscle contractions (squat and bicep curls). The use of WBV accessories such as hand straps attached to the platform and a soft surface mat were also evaluated. Surface electromyography (sEMG) was measured for the medial gastrocnemius (MG), vastus lateralis (VL), and biceps brachii (BB) muscles in fourteen healthy older adults (74.8±4.5 years; mean±SD) with a WBV stimulus at an acceleration of 40 m s(-2) (30 Hz High, 2.5 mm or 46 Hz Low, 1.1 mm). WBV increased lower body (VL and MG) sEMG vs baseline (no WBV) though this was decreased with the use of the soft mat. The addition of the bicep curl with hand straps had no effect on lower body sEMG. WBV also increased BB sEMG vs baseline which was further increased when using the hand straps. There was no upper body effect of the soft mat. This study demonstrates WBV increases both lower and upper body muscle activity in healthy older adults. Moreover, WBV accessories such as hand straps attached to the platform or a soft surface mat may be used to alter exercise intensity. 相似文献
976.
Wilson JM Marin PJ Rhea MR Wilson SM Loenneke JP Anderson JC 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(8):2293-2307
The primary objective of this investigation was to identify which components of endurance training (e.g., modality, duration, frequency) are detrimental to resistance training outcomes. A meta-analysis of 21 studies was performed with a total of 422 effect sizes (ESs). Criteria for the study included were (a) compare strength training alone to strength plus endurance training (concurrent) or to compare combinations of concurrent training; (b) the outcome measures include at least one measure of strength, power, or hypertrophy; and (c) the data necessary to calculate ESs must be included or available. The mean ES for hypertrophy for strength training was 1.23; for endurance training, it was 0.27; and for concurrent training, it was 0.85, with strength and concurrent training being significantly greater than endurance training only. The mean ES for strength development for strength training was 1.76; for endurance training, it was 0.78; and for concurrent training, it was 1.44. Strength and concurrent training was significantly greater than endurance training. The mean ES for power development for strength training only was 0.91; for endurance training, it was 0.11; and for concurrent training, it was 0.55. Significant differences were found between all the 3 groups. For moderator variables, resistance training concurrently with running, but not cycling, resulted in significant decrements in both hypertrophy and strength. Correlational analysis identified significant negative relationships between frequency (-0.26 to -0.35) and duration (-0.29 to -0.75) of endurance training for hypertrophy, strength, and power. Significant relationships (p < 0.05) between ES for decreased body fat and % maximal heart rate (r = -0.60) were also found. Our results indicate that interference effects of endurance training are a factor of the modality, frequency, and duration of the endurance training selected. 相似文献
977.
Díaz V Peinado AB Vleck VE Alvarez-Sánchez M Benito PJ Alves FB Calderón FJ Zapico AG 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(8):2209-2219
This study investigated the changes in cardiorespiratory response and running performance of 9 male "Talent Identification" (TID) and 6 male Senior Elite (SE) Spanish National Squad triathletes during a specific cycle-run (C-R) test. The TID and SE triathletes (initial age 15.2 ± 0.7 vs. 23.8 ± 5.6 years, p = 0.03; V(O2)max 77.0 ± 5.6 vs. 77.8 ± 3.6 ml · kg(-1) · min(-1), nonsignificant) underwent 3 tests through the competitive period and the preparatory period, respectively, of 2 consecutive seasons: test 1 was an incremental cycle test to determine the ventilatory threshold (Th(vent)); test 2 (C-R) was 30-minute constant load cycling at the Th(vent) power output followed by a 3-km time-trial run; and test 3 (isolated control run [R]) was an isolated 3-km time-trial control run, in randomized counterbalanced order. In both seasons, the time required to complete the C-R 3-km run was greater than for R in TID (11:09 ± 00:24 vs. 10:45 ± 00:16 min:ss, p < 0.01 and 10:24 ± 00:22 vs. 10:04 ± 00:14, p = 0.006, for season 2005-2006 and 2006-2007, respectively) and SE (10:15 ± 00:19 vs. 09:45 ± 00:30, p < 0.001 and 09:51 ± 00:26 vs. 09:46 ± 00:06, p = 0.02 for season 2005-2006 and 2006-2007, respectively). Compared with the first season, the completion of the time-trial run was faster in the second season (6.6%, p < 0.01 and 6.4%, p < 0.01, for C-R and R tests, respectively) only in TID. Changes in post cycling run performance were accompanied by changes in pacing strategy, but there were only slight or nonsignificant changes in the cardiorespiratory response. Thus, the negative effect of cycling on performance may persist, independently of the period, over 2 consecutive seasons in TID and SE triathletes; however, improvements over time suggests that monitoring running pacing strategy after cycling may be a useful tool to control performance and training adaptations in TID. 相似文献
978.
To better understand the mating systems of majoid crabs, we studied the functional anatomy of the female reproductive systems of the spider crabs Leurocyclus tuberculosus and Libinia spinosa, comparing them with those of other Majoidea. Adult females were measured and dissected, and their reproductive systems described macroscopically and histologically. In females of both species, the seminal receptacles are paired globular structures of ecto‐mesodermal origin. The mesoderm‐derived region is lined by a stratified epithelium. The anchoring, proliferative, and secretory strata are clearly recognizable . The ectoderm‐derived region is lined by a simple cylindrical epithelium underlying a cuticle that increases in thickness toward the vagina. The transition between the ectoderm and mesoderm‐derived regions is abrupt, with differences between the studied species: Li. spinosa has a “velum,” whereas Le. tuberculosus presents prominent “folds.” In both species, the position in which the oviduct is connected to the seminal receptacles is intermediate between the dorsal and ventral types previously described in other eubrachyurans. The seminal receptacles of the studied species show four different conditions, which can be distinguished macroscopically based on their shape and amount of sperm stored. We compare our data with those from other Majoidea in an attempt to determine whether the morphology of the seminal receptacles is related to different mating strategies or behaviors. 相似文献
979.
Agustín Lahora Cano Pedro Sánchez Gómez Juan Francisco Jiménez Martínez 《Folia Geobotanica》2012,47(3):317-335
Currently, there are nine species classified within the genus Coronilla (Loteae, Fabaceae); however, some populations discovered in the province of Almería, SE Spain, have features that are not present, as a whole, in the other known species. These plants are related to Coronilla juncea and C. minima, although several features of branches, leaves, flowers and seeds (zigzag branches; fleshy, deciduous leaves without hyaline margin; connate reddish stipules; very narrow seeds with fluted foveolae) are usually recognized as belonging to distinct species. To clarify the taxonomic status of these populations, morphological and genetic studies have been performed. The results obtained suggest that their separate classification is appropriate. Accordingly, a new species, Coronilla talaverae, whose currently recorded range is restricted to three populations in southeastern Spain is described here. Regarding its risk of extinction, the IUCN red list criteria have been followed to assess its category, proposing the status EN B1ab(i,ii,iii,v)+2ab(i,ii,iii,v). In addition, an identification key is provided for the species of the genus Coronilla. 相似文献
980.
Suárez-Souto MA Lara-Padilla E Reyna-Garfias H Viloria M López-Sánchez P Rivera-Aguilar V Miliar-García Á Kormanovski A Domínguez-López ML Campos-Rodríguez R 《Journal of physiology and biochemistry》2012,68(2):163-173
Although caloric restriction (CR) apparently has beneficial effects on the immune system, its effects on the immunological
function of the intestinal mucosa are little known. The present study explored the effect of CR on the innate and adaptive
intestinal immunity of mice. Balb/c mice were either fed ad libitum (control) or on alternate days fed ad libitum and fasted
(caloric restriction). After 4 months, an evaluation was made of IgA levels in the ileum, the gene expression for IgA and
its receptor (pIgR), as well as the expression of two antimicrobial enzymes (lysozyme and phospholipase A2) and several cytokines
of the intestinal mucosa. CR increased the gene expression of lysozyme and phospholipase A2. The levels of IgA were diminished
in the ileum, which apparently was a consequence of the reduced transport of IgA by pIgR. In ileum, CR increased the gene
expression for most cytokines, both pro- and anti-inflammatory. Hence, CR differentially modified the expression of innate
and adaptive immunity mediators in the intestine. 相似文献