469 research outputs found
The effect of concurrent resistance training on upper body strength, sprint swimming performance and kinematics in competitive adolescent swimmers: a randomized controlled trial
This study aimed to examine the effect of 9 weeks of concurrent resistance training (CRT) between resistance on dry land (bench press (BP) and medicine ball throw) and resistance in water (water parachute and hand paddles) on muscle strength, sprint swimming performance and kinematic variables compared by the usual training (standard in-water training). Twenty-two male competitive swimmers participated in this study and were randomly allocated to two groups. The CRT group (CRTG, age = 16.5 ± 0.30 years) performed a CRT program, and the control group (CG, age = 16.1 ± 0.32 years) completed their usual training. The independent variables were measured pre-and post-intervention. The findings showed that the one-repetition maximum bench press (1RM BP) was improved only after a CRT program (d = 2.18; +12.11 ± 1.79%). Moreover, all sprint swimming performances were optimized in the CRT group (d = 1.3 to 2.61; â4.22 ± 0.18% to â7.13 ± 0.23%). In addition, the findings revealed an increase in velocity and stroke rate (d = 1.67, d = 2.24; 9.36 ± 2.55%, 13.51 ± 4.22%, respectively) after the CRT program. The CRT program improved the muscle strength, which, in turn, improved the stroke rate, with no change in the stroke length. Then, the improved stroke rate increased the swimming velocity. Ultimately, a faster velocity leads to better swim performancesinfo:eu-repo/semantics/publishedVersio
Effects of nitrogen rates on grain yield and nitrogen agronomic efficiency of durum wheat genotypes under different environments
Durum wheat is an important staple food crop in Tunisia and other Mediterranean
countries and is grown in various climatic conditions. Production and
yield are however severely limited not only by drought events but also by
reduced levels of nitrogen fertilisation. A study was carried out at two locations
in the sub-humid area of Tunisia: Mateur in 2009â10 and 2010â11 and Beja in
2011â12 and 2012â13 under rainfed conditions. Four durum wheat genotypes
(landraces: Bidi, Azizi; improved: Om Rabia, Khiar) were evaluated for nitrogen
agronomic efficiency and related agronomic traits under various nitrogen
rates: 0, 50, 100, 150, 200 and 250 kgNhaâ1, with three replications. There was
a significant interaction effect (P †0.001) environments Ă genotypes ĂN treatments
for grain yield (GY), biomass yield (BY), harvest index (HI), partial factor
productivity of applied nitrogen (PFPN) and nitrogen agronomic use efficiencies
(NAE). GY was the most affected trait by nitrogen applied showing an increase
of 94% under high N treatment (250 kgNhaâ1) compared to control plots without
N treatments. A significant linear regression exists between GY (0 N) and
GY for the different N rates (r =0.70; P < 0.001). This effect was more pronounced
for improved genotypes than landraces for all parameters excepting
BY and NAEBY. BY showed +11% increase in landraces than improved genotypes.
PFPN showed an average decrease of 65% under high-N fertilisation with
10% prevalence for improved genotypes. Landraces tend to promote vegetative
growth while grain filling efficiency was higher for improved genotype
The response to flexibility: country intervention choices in the first four rounds of the GAVI Health Systems Strengthening applications
Since December 2005 the GAVI Alliance (GAVI) Health Systems Strengthening (HSS) window has offered predictable funding to developing countries, based on a combined population and economic formula. This is intended to assist them to address system constraints to improved immunization coverage and health care delivery, needed to meet the Millennium Development Goals. The application process invites countries to prioritize specific system constraints not adequately addressed by other donors, and allows them to allocate their eligible funds accordingly. This article presents an analysis of the first four rounds of countries' funding applications. These requested funding for a variety of health system initiatives that reflected country-specific requirements, and were not limited to improving immunization coverage. Analyses identified a dominance of operational-level health service provision activities, and an absence of interventions related to demand and financing. While the proposed activities are only now being implemented, the results of this study provide evidence that the open application process employed by the HSS window has led to a shift in analysis and planningâfrom the programmatic to the systemicâin the countries whose applications have been approved. However, the proposed responses to identified constraints are dominated by short-term operational responses, rather than more complex, longer term approaches to health system strengthenin
Variation of Grain Yield, Grain Protein Content and Nitrogen Use Efficiency Components under Different Nitrogen Rates in Mediterranean Durum Wheat Genotypes
Nitrogen (N) is a crucial nutrient for plant growth and development. To optimize agricultural environments, N fertilizers represent a critical tool to regulate crop productivity. The improvement of nitrogen use efficiency (NUE) represents a promising tool that may enable cereal production to meet future food demand. Wheat reported contrasting behaviors in N utilization showing specific abilities depending on genotype. This study selected two landraces and two improved genotypes from Northern Africa to investigate grain yield (GY), grain protein content (GPC) and NUE. Plants were grown under three levels of N supply: 0, 75, 150 kg N haâ1 and for two consecutive years. Results reported a better NUE (0.40 kg.kg Nâ1) obtained under 150 kg N haâ1, while N utilization efficiency (NUtE) showed a 13% increase using 75 kg N haâ1 compared with 150 kg N haâ1. Under low nitrogen rate (0 N), crop N supply (CNS) and N uptake efficiency (NUpE) were shown as determinant factors for improved genotypes GY (R2 = 0.72), while NUtE represented the most determinant component for GPC in landraces (R2 = 0.92). Multivariate regression models explained the dependence in GPC on NUE, NUpE, and NUtE. In conclusion, our results recognize GPC and NUtE as suitable selection traits to identify durum wheat with higher NUE
Heat and Mass Transfer Enhancement in Absorption of Vapor in Laminar Liquid Film by Adding Nano-Particles
In this paper, a numerical study was performed. The effect of nanoparticles on the absorption of vapor into a liquid film of lithium bromide aqueous solution flowing down over a cooled vertical channel is examined. The present model uses the numerical finite volume method to solve the parabolic governing equations for two-dimensional and laminar flow. In this model, the cooling water flows countercurrent to a solution of concentrated lithium bromide mixed with the nanoparticles. The water vapor is then absorbed at the interface of the absorbent film and diffused into the binary nanofluid (water-LiBr+nanoparticles). The numerical results indicate that the mass and heat transfer in binary nanofluids are enhanced more than that in base fluid and the highest absorption mass flux is observed by adding argent (Ag) nanoparticles. The results of the effects of operating conditions show that the effectiveness of the nanofluid becomes higher than that with the base fluid when the Reynolds number and inlet concentration are lower and when the inlet temperature solution and inlet pressure are higher
Developmental variations in plasma leptin, leptin soluble receptor and their molar ratio in healthy infants
<p>Abstract</p> <p>Background</p> <p>Leptin and its soluble receptor (sOB-R) are important to regulation of body composition but there are no data on the developmental variations in these plasma variables and their relationship with body composition measurements,</p> <p>Methods</p> <p>Weight, length, and body composition (bone, fat and lean mass) by dual energy absorptiometry, and plasma variables were measured in healthy infants at 2, 4, 8 and 12 months.</p> <p>Results</p> <p>15 whites and 29 African Americans (21 males and 23 females) with mean birth weight 3357 +/- 45 (SEM) g and gestation of 39.3 +/- 0.17 weeks were studied. The overall Z score for weight, length and weight for length during the study were 0.00 +/- 0.15, -0.08 +/- 0.11 and 0.12 +/- 0.14 respectively. With increasing age, plasma leptin (1.0 to 18.2, median 5.5 ng/mL) and sOB-R:leptin molar ratio (10.1 to 247.4, median 59.9) were lowered (r = -0.47, p < 0.01; and r = -0.37, p < 0.05 respectively), best predicted by weight Z score and percentage of fat mass, and higher in African American and female. Presence of body composition measurements eliminated the race and gender effect on the plasma variables. Plasma sOB-R (49.5 to 173.9, median 81.3 ng/mL) did not change significantly with age and was correlated and predicted only by body composition measurements.</p> <p>Conclusion</p> <p>In healthy growing infants, plasma leptin but not sOB-R decreases with age. Gender, race and anthropometric measurements are additional physiological determinants predictive of plasma leptin and the receptor:ligand ratio. However, body composition is the only variable that can predict plasma leptin and its soluble receptor and the receptor: ligand ratio; and body composition measurements eliminated the race and gender effect on these plasma variables.</p
The Molecular Biology Database Collection: 2008 update
The Nucleic Acids Research online Molecular Biology Database Collection is a public repository that lists more than 1000 databases described in this and previous Nucleic Acids Research annual database issues, as well as a selection of molecular biology databases described in other journals. All databases included in this Collection are freely available to the public. The 2008 update includes 1078 databases, 110 more than the previous one. The links to more than 80 databases have been updated and 25 obsolete databases have been removed from the list. The complete database list and summaries are available online at the Nucleic Acids Research web site, http://nar.oxfordjournals.org/
Rhaponticum acaule (L) DC essential oil: chemical composition, in vitro antioxidant and enzyme inhibition properties
Background: α-glucosidase is a therapeutic target for diabetes mellitus (DM) and α-glucosidase inhibitors play a
vital role in the treatments for the disease. Furthermore, xanthine oxidase (XO) is a key enzyme that catalyzes
hypoxanthine and xanthine to uric acid which at high levels can lead to hyperuricemia which is an important cause
of gout. Pancreatic lipase (PL) secreted into the duodenum plays a key role in the digestion and absorption of fats.
For its importance in lipid digestion, PL represents an attractive target for obesity prevention.
Methods: The flowers essential oil of Rhaponticum acaule (L) DC (R. acaule) was characterized using gas
chromatography-mass spectrometry (GC-MS). The antioxidant activities of R. acaule essential oil (RaEO) were also
determined using 2,2â-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), reducing power,
phosphomolybdenum, and DNA nicking assays. The inhibitory power of RaEO against α-glucosidase, xanthine
oxidase and pancreatic lipase was evaluated. Enzyme kinetic studies using Michaelis-Menten and the derived
Lineweaver-Burk (LB) plots were performed to understand the possible mechanism of inhibition exercised by the
components of this essential oil.
Results: The result revealed the presence of 26 compounds (97.4%). The main constituents include germacrene D
(49.2%), methyl eugenol (8.3%), (E)-ÎČ-ionone (6.2%), ÎČ-caryophyllene (5.7%), (E,E)-α-farnesene (4.2%),
bicyclogermacrene (4.1%) and (Z)-α-bisabolene (3.7%). The kinetic inhibition study showed that the essential oil
demonstrated a strong α-glucosidase inhibiton and it was a mixed inhibitor. On the other hand, our results
evidenced that this oil exhibited important xanthine oxidase inhibitory effect, behaving as a non-competitive
inhibitor. The essential oil inhibited the turkey pancreatic lipase, with maximum inhibition of 80% achieved at
2 mg/mL. Furthermore, the inhibition of turkey pancreatic lipase by RaEO was an irreversible one.
Conclusion: The results revealed that the RaEO is a new promising potential source of antioxidant compounds,
endowed with good practical applications for human health.
Keywords: α-glucosidase, Antioxidant activity, Chemical composition, Pancreatic lipase inhibition, Rhaponticum
acaule essential oil, Xanthine oxidase
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