The effect of carbohydrate mouth rinse on maximal strength and strength endurance

It has been previously reported that carbohydrate (CHO) mouth rinse can improve exercise performance. The proposed mechanism involves increased activation of brain regions believed to be responsible for reward/motivation and motor control. Since strength-related performance is affected by central drive to the muscles, it seems reasonable to hypothesize that the positive CNS response to oral CHO sensing may counteract the inhibitory input from the muscle afferent pathways minimizing the drop in the central drive. The purpose of the current study was to test if CHO mouth rinse affects maximum strength and strength endurance performance. Twelve recreationally strength-trained healthy males (age 24.08 +/- 2.99 years; height 178.09 +/- 6.70 cm; weight 78.67 +/- 8.17 kg) took part in the study. All of the tests were performed in the morning, after an 8 h overnight fasting. Subjects were submitted to a maximum strength test (1-RM) and a strength endurance test (six sets until failure at 70% of 1-RM), in separate days under three different experimental conditions (CHO mouth rinse, placebo-PLA mouth rinse and control-CON) in a randomized crossover design. The CHO mouth rinse (25 ml) occurred before every attempt in the 1-RM test, and before every set in the endurance strength test. Blood glucose and lactate were measured immediately before and 5 min post-tests. There were no significant differences in 1-RM between experimental conditions (CHO 101 +/- 7.2 kg; PLA 101 +/- 7.4 kg; CON 101 +/- 7.2 kg; p = 0.98). Furthermore, there were no significance between trial differences in the number of repetitions performed in each set (p = 0.99) or the total exercise volume (number of repetitions x load lifted [kg]) (p = 0.98). A main effect for time (p < 0.0001) in blood lactate concentration was observed in both tests (1-RM and strength endurance). Blood glucose concentration did not differ between conditions. In conclusion, CHO mouth rinse does not affect maximum strength or strength endurance performance.

A special judo fitness test classificatory table

Background and Study Aim: Judo is very physiological demanding sport, but there are no many physical fitness specific tests. One of the most used specific judo tests is the Special Judo Fitness Test (SJFT) proposed by Sterkowicz ( 1995). Although this test has been used by many coaches in different countries no classificatory table was found to classify the judo athletes according to their results. Thus, the aim of this work was to present a classificatory table for this test. Material/Methods: For this purpose 141 judo athletes ( mean +/-standard deviation: 21.3+/-4.5years-old; 74.2+/-15.9 kg of body mass and 176.7+/-8.2 cm of height; judo ranking between 3(rd) kyu and 3(rd) dan) familiarized with the SJFT performed it once in order to provide data to establish a classificatory table. Results: After the analysis of data distribution a five scale table (20% for each classificatory category) was developed considering the variables used in the SJFT ( number of throws, heart rate after and 1 min after the test and index). Conclusions: The classificatory table can help coaches using the SJFT to classify their athletes` level and to monitor their physical fitness progress.

Physiological, performance, and nutritional profile of the Brazilian olympic wushu (kung-fu) team

Artioli, GG, Gualano, B, Franchini, E, Batista, RN, Polacow, VO, and Lancha, AH Jr. Physiological, performance, and nutritional profile of the Brazilian Olympic Wushu (kung-fu) team. J Strength Cond Res 23(1): 20-25, 2009-The purpose of the present study was to determine physiological, nutritional, and performance profiles of elite Olympic Wushu (kung-fu) athletes. Ten men and four women elite athletes took part in the study. They completed the following tests: body composition, nutritional assessment, upper-body Wingate Test, vertical jump, lumbar isometric strength, and flexibility. Blood lactate was determined at rest and after the Wingate Test. Blood lactate was also determined during a training session (combat and Taolu training). We found low body fat (men: 9.5 +/- 6.3%; women: 18.0 +/- 4.8%), high flexibility (sit-and-reach-men: 45.5 +/- 6.1 cm; women: 44.0 +/- 6.3 cm), high leg power (vertical jump-men: 37.7 +/- 8.4 cm; women: 32.3 +/- 1.1 cm), high lumbar isometric strength (men: 159 6 13 cm; women: 94 6 6 cm), moderate arm mean and peak power (Wingate Test-men: 4.1 +/- 0.4 and 5.8 +/- 0.5 W.kg(-1), respectively; women: 2.5 +/- 0.3 and 3.4 +/- 0.3 W.kg(-1), respectively), and elevated blood lactate after the Wingate Test (men: 10.8 +/- 2.0 mmol.L(-1); women: 10.2 +/- 2.0 mmol.L(-1)) and during training (combat: 12.0 +/- 1.8 mmol.L(-1); Taolu: 7.7 +/- 3.3 mmol.L(-1)). Men athletes consume a high-fat, low-carbohydrate diet, whereas women consume a moderate, high-carbohydrate diet. Energy consumption was markedly variable. In conclusion, Olympic Wushu seems to be a highly anaerobic-dependent combat sport. Low body fat, high flexibility, leg anaerobic power, isometric strength, and moderately high arm anaerobic power seem to be important for successful competitive performance.

A Semi-Tethered Test for Power Assessment in Running

We analyzed the usefulness of a semi-tethered field running test (STR) and the relationships between indices of anaerobic power, anaerobic capacity and running performance in 9 trained male sprinters (22.2 +/- 2.9 yrs, 176 +/- 1 cm, 68.0 +/- 9.4 kg). STR involved an all out 120 m run attached to an apparatus that enabled power calculation from force and velocity measures. Subjects also carried out a cycloergometer Win-gate Anaerobic Test (WT), an all out 300 m run and had accessed their maximal accumulated oxygen deficit (MAOD) on a treadmill. Peak and mean powers attained in STR (1 720 +/- 221 and 1 391 +/- 201 W) were greater but significantly related (r=0.82; P<0.01) to those in the WT (808 +/- 130 and 603 +/- 87 W). In addition, power measures derived from the STR were stronger related to running performance compared to those from the WT (r=0.81-0.94 vs. 0.68-0.84; P<0.05). Relationships between MAOD and most power indices were only weak to moderate. These results support the usefulness of STR for specific power assessment in field running and suggest that anaerobic power and capacity are not related entities, irrespective of having been evaluated using similar or dissimilar exercise modes.

An investigation of phosphate adsorption from aqueous solution onto hydrous niobium oxide prepared by co-precipitation method

The synthetic hydrous niobium oxide has been used for phosphate removal from the aqueous solutions. The kinetic data correspond very well to the pseudo second-order equation The phosphate removal tended. to increase with a decrease of pH. The equilibrium data describe very well the Langmuir isotherm. The peak appearing at 1050 cm(-1) in IR spectra after adsorption was attributed to the bending vibration of adsorbed phosphate. The adsorption capacities are high, and increased with increasing temperature. The evaluated Delta G degrees and Delta H degrees indicate the spontaneous and endothermic nature of the reactions. The adsorptions occur with increase in entropy (Delta S positive) value suggest increase in randomness at the solid-liquid interface during the adsorption. A phosphate desorbability of approximately 60% was observed with water at pH 12, which indicated a relatively strong bonding between the adsorbed phosphate and the sorptive sites on the surface of the adsorbent. (C) 2008 Elsevier B.V. All rights reserved.

An alternative application to the Portuguese agro-industrial residue: Wheat straw

The effects of alkaline treatments of the wheat straw with sodium hydroxide were investigated. The optimal condition for extraction of hemicelluloses was found to be with 0.50 mol/l sodium hydroxide at 55C for 2 h. This resulted in the release of 17.3% of hemicellulose (% dry starting material), corresponding to the dissolution of 49.3% of the original hemicellulose. The yields were determined by gravimetric analysis and expressed as a proportion of the starting material. Chemical composition and physico-chemical properties of the samples of hemicelluloses were elucidated by a combination of sugar analyses, Fourier transform infrared (FTIR), and thermal analysis. The results showed that the treatments were very effective on the extraction of hemicelluloses from wheat straw and that the extraction intensity (expressed in terms of alkali concentration) had a great influence on the yield and chemical features of the hemicelluloses. The FTIR analysis revealed typical signal pattern for the hemicellulosic fraction in the 1,200-1,000 cm(-1) region. Bands between 1,166 and 1,000 cm(-1) are typical of xylans.

Characterization of nickel-niobium composite electrocoatings

The electrodeposition of nickel based composites is been performed in order to improve properties of nickel layers, such as hardness, wear resistance, lubrication, corrosion resistance and catalytic activity. In the present work Nb powders (20 mu m average size) and Ni were codeposited on 1020 carbon steel by galvanostatic electrolysis of Watts bath, using 10, 20 and 40 mA/cm(2) cathodic current density and 240, 400 and 550 rpm electrolyte stirring rate. The morphology and texture of the coatings, Nb incorporated volume fraction, microhardness, adhesion to the substrate and corrosion behavior were evaluated. The Ni-Nb composite layers presented a rough morphology with randomly oriented Ni grains, whereas pure Ni coatings were smooth and showed highly preferred orientation in the [110] or [100] direction. The volume fraction of Nb in the composites determined by image analysis ranged from 8.5 to 19%. The 400 rpm stirring rate led to the highest Nb content (16 to 19016) for all current densities investigated The microhardness of the composite layers was higher than that of pure Ni coatings due to refining of Ni grains induced by incoporation of Nb particles. The adhesion of the coatings estimated qualitatively by bend test was found satisfactory. The Ni-Nb composites presented lower corrosion rate than Ni coatings in both 3% NaCl and 20% H2SO4 solutions.

Thermodynamic and kinetic investigations of phosphate adsorption onto hydrous niobium oxide prepared by homogeneous solution method

The adsorption kinetics of phosphate onto Nb(2)O(5)center dot nH(2)O was investigated at initial phosphate concentrations 10 and 50 mg L(-1). The kinetic process was described by a pseudo second-order rate model very well. The adsorption thermodynamics was carried out at 298, 308, 318, 328 and 338 K. The positive values of both Delta H and Delta S suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. Delta G values obtained were negative indicating a spontaneous adsorption process. The Langmuir model described the data better than the Freundlich isotherm model. The peak appearing at 1050 cm(-1) in IR spectra after adsorption was attributed to the bending vibration of adsorbed phosphate. The effective desorption could be achieved using water at pH 12. (C) 2010 Elsevier B.V. All rights reserved.

Adsorption kinetic, thermodynamic and desorption studies of phosphate onto hydrous niobium oxide prepared by reverse microemulsion method

A type of Nb(2)O(5)center dot 3H(2)O was synthesized and its phosphate removal potential was investigated in this study. The kinetic study, adsorption isotherm, pH effect, thermodynamic study and desorption were examined in batch experiments. The kinetic process was described by a pseudo-second-order rate model very well. The phosphate adsorption tended to increase with a decrease of pH. The adsorption data fitted well to the Langmuir model with which the maximum P adsorption capacity was estimated to be 18.36 mg-Pg(-1). The peak appearing at 1050 cm(-1) in IR spectra after adsorption was attributed to the bending vibration of adsorbed phosphate. The positive values of both Delta H degrees and Delta S degrees suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. Delta G degrees values obtained were negative indicating a spontaneous adsorption process. A phosphate desorbability of approximately 68% was observed with water at pH 12, which indicated a relatively strong bonding between the adsorbed phosphate and the sorptive sites on the surface of the adsorbent. The immobilization of phosphate probably occurs by the mechanisms of ion exchange and physicochemical attraction. Due to its high adsorption capacity, this type of hydrous niobium oxide has the potential for application to control phosphorus pollution.

Production, characterization and application of activated carbon from brewer`s spent grain lignin

Different types of activated carbon were prepared by chemical activation of brewer`s spent grain (BSG) lignin using H(3)PO(4) at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 degrees C), according to a 2(2) full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, and used for detoxification of BSG hemicellulosic hydrolysate (a mixture of sugars, phenolic compounds, metallic ions, among other compounds). BSG carbons presented BET surface areas between 33 and 692 m(2)/g, and micro- and mesopores with volumes between 0.058 and 0.453 cm(3)/g. The carbons showed high capacity for adsorption of metallic ions, mainly nickel, iron, chromium, and silicon. The concentration of phenolic compounds and color were also reduced by these sorbents. These results suggest that activated carbons with characteristics similar to those commercially found and high adsorption capacity can be produced from BSG lignin. (C) 2009 Elsevier Ltd. All rights reserved.

A novel electrocatalyst support with proton conductive properties for polymer electrolyte membrane fuel cell applications

The objective of this study is to graft the Surface of carbon black, by chemically introducing polymeric chains (Nafion (R) like) with proton-conducting properties. This procedure aims for a better interaction of the proton-conducting phase with the metallic catalyst particles, as well as hinders posterior support particle agglomeration. Also loss of active surface call be prevented. The proton conduction between the active electrocatalyst site and the Nafion (R) ionomer membrane should be enhanced, thus diminishing the ohmic drop ill the polymer electrolyte membrane fuel cell (PEMFC). PtRu nanoparticles were supported on different carbon materials by the impregnation method and direct reduction with ethylene glycol and characterized using amongst others FTIR, XRD and TEM. The screen printing technique was used to produce membrane electrode assemblies (MEA) for single cell tests in H(2)/air(PEMFC) and methanol operation (DMFC). In the PEMFC experiments, PtRu supported on grafted carbon shows 550 mW cm(-2) gmetal(-1) power density, which represents at least 78% improvement in performance, compared to the power density of commercial PtRu/C ETEK. The DMFC results of the grafted electrocatalyst achieve around 100% improvement. The polarization Curves results clearly show that the main Cause of the observed effect is the reduction in ohmic drop, caused by the grafted polymer. (C) 2009 Elsevier B.V. All rights reserved.

Flux Pinning Optimization of MgB(2) Bulk Samples Prepared Using High-Energy Ball Milling and Addition of TaB(2)

MgB(2) is considered to be an important conductor for applications. Optimizing flux pinning in these conductors can improve their critical currents. Doping can influence flux pinning efficiency and grain connectivity, and also affect the resistivity, upper critical field and critical temperature. This study was designed to attempt the doping of MgB(2) on the Mg sites with metal-diborides using high-energy ball milling. MgB(2) samples were prepared by milling pre-reacted MgB(2) and TaB(2) powders using a Spex 8000M mill with WC jars and balls in a nitrogen-filled glove box. The mixing concentration in (Mg(1-x)Ta(x))B(2) was up to x = 0.10. Samples were removed from the WC jars after milling times up to 4000 minutes and formed into pellets using cold isostatic pressing. The pellets were heat treated in a hot isostatic press (HIP) at 1000 degrees C under a pressure of 30 kpsi for 24 hours. The influence that milling time and TaB(2) addition had on the microstructure and the resulting superconducting properties of TaB(2)-added MgB(2) is discussed. Improvement J(c) of at high magnetic fields and of pinning could be obtained in milled samples with added TaB(2) The sample with added 5at.% TaB(2) and milled for 300 minutes showed values of J(c) similar to 7 x 10(5) A/cm(2) and F(p) similar to 14 GN/m(3) at 2T, 4.2 K. The milled and TaB(2)-mixed samples showed higher values of mu(0)H(irr) than the unmilled-unmixed sample.

Evaluation of Electrical Properties of Lap Joints for BSCCO and YBCO Tapes

The joint process between tapes of coated conductors is a critical issue for the most of the applications of high temperature superconductors (HTS). Using different fabrication techniques joints of YBCO coated superconductors were prepared and characterized through electrical measurements. For soldering material low melting point eutectic alloys, such as In-Sn (m.p. 116 degrees C) and Sn-Pb (m. p. 189 degrees C) were selected to prepare lap joints with effective length between 1 to 20 cm. The splice resistance and the critical current of the joints were evaluated by I-V curve measurements with the maximum current strength above the critical current, in order to evaluate the degree of degradation for each joint method. Pressed lap joints prepared with tapes without external reinforcement presented low resistance lap joint nevertheless some critical current degradation occurs when strong pressing is applied. When mechanical pressure is applied during the soldering process we can reduce the thickness of the solder alloy and a residual resistance arises from contributions of high resistivity matrix and external reinforcement. The lap joints for reinforced tape were prepared using two methods: the first, using ""as-supplied"" tape and the other after reinforcement-removal; in the latter case, the tapes were resoldered using Sn-Pb alloy. The results using several joint geometries, distinct surface preparation processes and different soldering materials are presented and analysed. The solder alloy with lower melting point and the longer joint length presented the smallest joint resistance.

Influence of laser surface texturing on surface microstructure and mechanical properties of adhesive joined steel sheets

This work discusses the resultant microstructure of laser surface treated galvanised steel and the mechanical properties of adhesively bonded surfaces therein. The surface microstructure obtained at laser intensities between 170 and 1700 MW cm 22 exhibit zinc melting and cavity formation. The wavy surface morphology of the treated surface exhibits an average roughness Ra between 1.0 and 1.5 mu m, and a mean roughness depth R(z) of 8.6 mu m. Atomic force microscopic analyses revealed that the R(z) inside the laser shot cavities increased from 68 to 243 nm when the incident laser intensity was increased from 170 to 1700 MW cm(-2). X-ray fluorescence analyses were used to measure Zn coating thicknesses as a function of process parameters. Both X-ray fluorescence and X-ray diffraction analyses demonstrated that the protective coating remains at the material surface, and the steel structure beneath was not affected by the laser treatment. Tensile tests under peel strength conditions demonstrated that the laser treated adhesively joined samples had resistance strength up to 88 MPa, compared to a maximum of only 23 MPa for the untreated surfaces. The maximum deformation for rupture was also greatly increased from 0.07%, for the original surface, to 0.90% for the laser treated surfaces.

Corrosion behavior of Ti-xNb-13Zr alloys in Ringer`s solution

Ti-6Al-4V alloy has been widely used in restorative surgery due to its high corrosion resistance and biocompatibility. Nevertheless, some studies showed that V and Al release in the organism might induce cytotoxic effects and neurological disorders, which led to the development of V-free alloys and both V- and Al-free alloys containing Nb, Zr, Ta, or Mo. Among these alloys, Ti-13Nb-13Zr alloy is promising due to its better biomechanical compatibility than Ti-6Al-4V. In this work, the corrosion behavior of Ti, Ti-6Al-4V, and Ti-xNb-13Zr alloys (x=5, 13, and 20) was evaluated in Ringer`s solution (pH 7.5) at 37 degrees C through open-circuit potential measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy. Spontaneous passivity was observed for all materials in this medium. Low corrosion current densities (in the order of 10(-7) A/cm(2)) and high impedance values (in the order of 10(5) Omega cm(2) at low frequencies) indicated their high corrosion resistance. EIS results showed that the passivating films were constituted of an outer porous layer (very low resistance) and an inner compact layer (high resistance), the latter providing the corrosion resistance of the materials. There was evidence that the Ti-xNb-13Zr alloys were more corrosion resistant than both Ti and Ti-6Al-4V in Ringer`s solution.