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1.
This opinion piece offers a commentary on the four papers that address the theme of the development of self and other understanding with a view to highlighting the important contribution of developmental research to understanding of mechanisms of social cognition. We discuss potential mechanisms linking self–other distinction and empathy, implications for grouping motor, affective and cognitive domains under a single mechanism, applications of these accounts for joint action and finally consider self–other distinction in group versus dyadic settings.  相似文献   
2.
The TGF-β1-Smad pathway is a well-known negative regulator of muscle growth; however, its potential role in resistance training-induced muscle hypertrophy is not clear. The present study proposed to determine whether and how this pathway may be involved in resistance training-induced muscle hypertrophy. Skeletal muscle samples were collected from the control, trained (RT), control + SB431542 (CITGF), and trained + SB431542 (RTITGF) animals following 3, 5, and 8 weeks of resistance training. Inhibition of the TGF-β1-Smad pathway by SB431542 augmented muscle satellite cells activation, upregulated Akt/mTOR/S6K1 pathway, and attenuated FOXO1 and FOXO3a expression in the CITGF group (all p < .01), thereby causing significant muscle hypertrophy in animals from the CITGF. Resistance training significantly decreased muscle TGF-β1 expression and Smad3 (P-Smad3S423/425) phosphorylation at COOH-terminal residues, augmented Smad2 (P-Smad2-LS245/250/255) and Smad3 (P-Smad3-LSer208) phosphorylation levels at linker sites (all p < .01), and led to a muscle hypertrophy which was unaffected by SB431542, suggesting that the TGF-β1-Smad signaling pathway is involved in resistance training-induced muscle hypertrophy. The effects of inhibiting the TGF-β1-Smad signaling pathway were not additive to the resistance training effects on FOXO1 and FOXO3a expression, muscle satellite cells activation, and the Akt/mTOR/S6K1 pathway. Resistance training effect of satellite cell differentiation was independent of the TGF-β1-Smad signaling pathway. These results suggested that the effect of the TGF-β1-Smad signaling pathway on resistance training-induced muscle hypertrophy can be attributed mainly to its diminished inhibitory effects on satellite cell activation and protein synthesis. Suppressed P-Smad3S423/425 and enhanced P-Smad2-LS245/250/255 and P-Smad3-LSer208 are the molecular mechanisms that link the TGF-β1-Smad signaling pathway to resistance training-induced muscle hypertrophy.  相似文献   
3.
Seven hundred and fifty-two rhizobacteria were isolated from 186 rhizosphere soil samples collected across tomato growing regions of Karnataka. Among them, 26% strains were Gram positive and other 74% were Gram negative and dominant being Bacillus and Pseudomonas. Sampling of different locations showed variation in species richness and diversity indices. Similarity matrix computed with Jaccard’s coefficient and principle coordinate analysis to correlate bacterial diversity revealed that rhizobacterial genera of Mysore, Mandya and Kolar soil samples were very closely related and rarefaction curve analysis indicated that these soil samples also harbored higher number of rhizobacteria which included all the genera studied. PGPR trait analysis revealed that most of the rhizobacteria were endowed with more than one beneficial trait which may act individually or simultaneously, and indole acetic acid production and phosphate solubilization are the two predominant traits exhibited by these rhizobacteria. Rhizobacterial isolates also showed a varied level of plant growth promotion traits and offered protection against fungal origin foliar and root pathogens. Among the nine regions studied, Mysore, Mandya and Kolar regions recorded higher percentage of promising PGPRs in comparison with other regions studied of Karnataka.  相似文献   
4.
The paper deals with the analysis of 2 × 2 table measures and describes several new possibilities for applying them. An estimate is given for HELLMICH's asymmetric K-measure and a possible extension of the contingency concept in a special 2×2 case is presented. The concept introduced and the recommended computer application of the 2×2 table measures is supported by new results obtained for the relationship between jaw joint pains and noises examined earlier by F. SCHMID and C. ZSCHEGE. With a larger number of observations the opportunity arises for a deeper analysis of this dental problem using path analysis. The plan of evaluation and the conncetion between the variables examined is illustrated by a path-diagram. The association tables determined on the basis of the (C) values introduced during the examination of jaw joint disturbances using association analysis draw attention to the special role of the left side of mastication. The paper raises ideas for further generalisations and indicates where further research is needed.  相似文献   
5.
The awareness of the importance of plant biodiversity has been considerably raised in both developed and developing countries over the last decade. Some of the debate has not been helpful in fostering collaboration or progress towards a more rational support network. The paper attempts to identify and categorize existing efforts in operation in a wide range of institutions and bodies ranging from essentially environmentally orientated to crop-based organizations. Current funding and training initiatives are discussed.  相似文献   
6.
An isolate (G15) of a bacterium, frequently isolated from roots of various plant species, was identified asSerratia plymuthica. At low temperature (viz. 2–8°C), the studied isolated readily produced a red pigment which proved useful in recognizing the bacteria on reisolation. In laboratory tests it exhibited strong antagonism againstBotrytis cinerea andGerlachia nivalis and moderate antagonism againstRhizoctonia solani, Fusarium culmorum andPythium sp. The bacterium significantly increased growth of lettuce plants when applied to the roots under non-sterile conditions in greenhouse tests. Various strains ofSerratia plymuthica are supposed to be common as rhizosphere bacteria under Swedish conditions.  相似文献   
7.
Twenty-four women completed a 20-week heavy-resistance weight training program for the lower extremity. Workouts were twice a week and consisted of warm-up exercises followed by three sets each of full squats, vertical leg presses, leg extensions, and leg curls. All exercises were performed to failure using 6-8 RM (repetition maximum). Weight training caused a significant increase in maximal isotonic strength (1 RM) for each exercise. After training, there was a decrease in body fat percentage (p less than 0.05), and an increase in lean body mass (p less than 0.05) with no overall change in thigh girth. Biopsies were obtained before and after training from the superficial portion of the vastus lateralis muscle. Sections were prepared for histological and histochemical examination. Six fiber types (I, IC, IIC, IIA, IIAB, and IIB) were distinguished following routine myofibrillar adenosine triphosphatase histochemistry. Areas were determined for fiber types I, IIA, and IIAB + IIB. The heavy-resistance training resulted in significant hypertrophy of all three groups: I (15%), IIA (45%), and IIAB + IIB (57%). These data are similar to those in men and suggest considerable hypertrophy of all major fiber types is also possible in women if exercise intensity and duration are sufficient. In addition, the training resulted in a significant decrease in the percentage of IIB with a concomitant increase in IIA fibers, suggesting that strength training may lead to fiber conversions.  相似文献   
8.
Effect of high-intensity endurance training on isokinetic muscle power   总被引:1,自引:0,他引:1  
The purpose of this study was to determine the effects of high-intensity endurance training on isokinetic muscle power. Six male students majoring in physical-education participated in high intensity endurance training on a cycle ergometer at 90% of maximal oxygen uptake (VO2max) for 7 weeks. The duration of the daily exercise session was set so that the energy expenditure equalled 42 kJ.kg-1 of lean body mass. Peak knee extension power was measured at six different speeds (30 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees, and 300 degrees.s-1) with an isokinetic dynamometer. After training, VO2max increased significantly from mean values of 51.2 ml.kg-1.min-1, SD 6.5 to 56.3 ml.kg-1.min-1, SD 5.3 (P less than 0.05). Isokinetic peak power at the lower test speeds (30 degrees, 60 degrees and 120 degrees.s-1) increased significantly (P less than 0.05). However, no significant differences in muscle peak power were found at the faster velocities of 180 degrees, 240 degrees, and 300 degrees.s-1. The percentage improvement was dependent on the initial muscle peak power of each subject and the training stimulus (intensity of cycle ergometer exercise).  相似文献   
9.
Differences between the effects of training at sea level and at simulated altitude on performance and muscle structural and biochemical properties were investigated in 8 competitive cyclists who trained for 3-4 weeks, 4-5 sessions/week, each session consisting of cycling for 60-90 min continuously and 45-60 min intermittently. Four subjects, the altitude group (AG), trained in a hypobaric chamber (574 torr = 2300 m above sea level), and the other four at sea level (SLG). Before and after training work capacity was tested both at simulated altitude (574 torr) and at sea level, by an incremental cycle ergometer test until exhaustion. Work capacity was expressed as total amount of work performed. Venous blood samples were taken during the tests. Leg muscle biopsies were taken at rest before and after the training period. AG exhibited an increase of 33% in both sea level and altitude performance, while SLG increased 22% at sea level and 14% at altitude. Blood lactate concentration at a given submaximal load at altitude was significantly more reduced by training in AG than SLG. Muscle phosphofructokinase (PFK) activity decreased with training in AG but increased in SLG. All AG subjects showed increases in capillary density. In conclusion, work capacity at altitude was increased more by training at altitude than at sea level. Work capacity at sea level was at least as much improved by altitude as by sea level training. The improved work capacity by training at altitude was paralleled by decreased exercise blood lactate concentration, increased capillarization and decreased glycolytic capacity in leg muscle.  相似文献   
10.
To compare the results obtained by incremental or constant work load exercises in the evaluation of endurance conditioning, a 20-week training programme was performed by 9 healthy human subjects on the bicycle ergometer for 1 h a day, 4 days a week, at 70-80% VO2max. Before and at the end of the training programme, (1) the blood lactate response to a progressive incremental exercise (18 W increments every 2nd min until exhaustion) was used to determine the aerobic and anaerobic thresholds (AeT and AnT respectively). On a different day, (2) blood lactate concentrations were measured during two sessions of constant work load exercises of 20 min duration corresponding to the relative intensities of AeT (1st session) and AnT (2nd session) levels obtained before training. A muscle biopsy was obtained from vastus lateralis at the end of these sessions to determine muscle lactate. AeT and AnT, when expressed as % VO2max, increased with training by 17% (p less than 0.01) and 9% (p less than 0.05) respectively. Constant workload exercise performed at AeT intensity was linked before training (60% VO2max) to a blood lactate steady state (4.8 +/- 1.4 mmol.l-1) whereas, after training, AeT intensity (73% VO2max) led to a blood lactate accumulation of up to 6.6 +/- 1.7 mmol.l-1 without significant modification of muscle lactate (7.6 +/- 3.1 and 8.2 +/- 2.8 mmol.kg-1 wet weight respectively). It is concluded that increase in AeT with training may reflect transient changes linked to lower early blood lactate accumulation during incremental exercise.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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