bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of aluminum nitride concentration on different physical properties of low density polyethylene based nanocomposites
Authors: Sohail Omer Bin , Bin-Dahman Osamah A. , Rahaman Mostafizur , Al-Harthi Mamdouh A. 
Published: February 2017

Abstract
In this study, blends of low-density polyethylene (LDPE)/aluminum nitride (AlN) ceramic nanocomposites have been prepared through melt blending technique. Increased loading of AIN leads to reduction in tensile properties but improvement in rheological property (storage modulus). The rheological behavior tends to become unique at higher frequencies (≥10 rad/s). Differential scanning calorimetry (DSC) results show that the total crystallinity has decreased with the increase in AlN loading in the composites. It is seen that there is an improvement in electrical conductivity, dielectric constant, and flammability properties with the addition of AlN in the nanocomposites. The experimental data of tensile modulus, electrical conductivity, and dielectric constant have been fitted with some available theoretical models to check the models’ applicability for the present composite systems. Results show that only Nicolais-Nicodemo model, McCullough model, and Rahaman-Khastgir model are applicable for predicting the tensile modulus, electrical conductivity, and dielectric constant of the composites, respectively.
Time reversal ultrasound focusing through multimode waveguides
Authors: Dawidowski David , Nauber Richard , Büttner Lars , Czarske Jürgen 
Published: February 2017

Abstract
Ultrasound imaging in harsh environments, such as the continuous steel casting process, benefits from a spatial separation of sensors and measuring volume to avoid damaging e.g. because of high temperatures. This can be achieved through acoustical multimode waveguides. To focus ultrasound in the measuring volume despite the complex sound propagation, we propose using the time reversal technique. We present numerical simulations and experiments using the phased array ultrasound Doppler velocimeter to focus through a water filled waveguide with a 64 element array. A resolution in the millimetre range is achieved for a 68 mm long waveguide.
In-Prozess-Charakterisierung
spiegelnder Oberflächen mit Laserstreulicht und leistungsfähiger
Hardware
Authors: Patzelt Stefan , Stehno Christian , Stöbener Dirk , Ströbel Gerald , Fischer Andreas 
Published: February 2017

Zusammenfassung
Laserstreulichtmessungen auf der Basis von
Specklekorrelationsverfahren charakterisieren Gestaltabweichung
opaker, technischer Oberflächen auf der Mikro- und
Nanometerskala. Anhand eines einzigen Streulichtbildes lässt sich
die Rauheit eines mit Laserlicht beleuchteten Oberflächenbereiches
mit mehreren Millimetern Durchmesser quantitativ bewerten. Mit hohen
Laser-Lichtleistungen, kurzen Belichtungszeiten und einer Kamera mit
hoher Bildrate lassen sich in laufenden Fertigungsprozessen
„scharfe“ Bilder erzeugen, die für die rauheitsbezogene
Bildauswertung geeignet sind. Die Bildauswertealgorithmen lassen sich
für die Implementierung auf einer leistungsfähigen Hardware
(FPGA – Field Programmable Gate Array) anpassen. Dies ermöglicht
fertigungsnahe und In-Prozess-Rauheitsmessungen an technischen
Oberflächen in Echtzeit mit einer Messrate von über
1,3 kHz und einer lückenlosen Oberflächenabdeckung von
nahezu 4 m2/min bei einer Bewegungsgeschwindigkeit von
1600 m/min. Der vorliegende Beitrag beschreibt den Aufbau und die
Funktionsweise eines In-Prozess-Laserstreulichtmesssystems für die
Charakterisierung schnell bewegter, spiegelnder Oberflächen und
stellt erste Messergebnisse vor.
Effect of Tip Configurations on Aerodynamic Performance of Variable Geometry Linear Turbine Cascade
Authors: Yue Guoqiang , Lin Hongfei , Jiang Yuting , Zheng Qun , Dong Ping 
Published: February 2017

Abstract
The variable geometry turbine (VGT) has been widely used in different fields due to its higher efficiency and lower fuel consumption at part-load. However, the flow field in a VGT is characterized by the leakage flow through the radial clearance of rotational vane compared with a general fixed vane turbine. Numerical simulations are conducted on a linear turbine cascade to reduce the leakage flow based on passive control method. The aerodynamic performances and flow fields are compared for four kinds of tip configuration firstly. Then, the effect of variable geometry on the linear turbine cascade aerodynamic performance is investigated for five installation angles ranging from –5 to 5 deg. In addition, the development patterns and trends of the tip leakage vortex and the passage vortex are analyzed. The results show that the squealer tip and the rotating axis have a significant impact on suppressing leakage flow. The leakage flow rate has a tendency to decrease, and the total pressure coefficient is gradually increased when installation angle ranges from –5 to 5 deg. The interactions between tip leakage vortex and passage vortex leads to the different trends on leakage flow at various installation angles and axial sections.
Facile Synthesis and Crystal Structure of [(PhSO2 N)2 WVI Cl2 (CH3CN)2] - the Oxidative Imination of W(CO)6 by N,N-Dichlorophenylsulphonamide
Authors: Roesky Herbert W. , Sundermeyer, Jörg , Schimkowiak Jürgen , Jones Peter G. , Noltemeyer Mathias , Schroeder Tina , Sheldrick George M. 
Published: February 2017

Abstract
The reaction of N,N-dichlorophenylsulphonamide with tungsten hexacarbonyl in refluxing CCl4 leads in good yield to the yellow polymeric complex [(PhSO2N)2WCl2]x, which may be converted to the octahedral nitrene complex [(PhSO2N)2WCl2(CH3CN)2] by recrystallisation from aceto­nitrile. Crystals of the acetonitrile complex are triclinic, space group P 1̅, a = 820.7(2), b = 1128.8(3), c = 1286.9(3) pm, α = 89.25(3), β = 89.54(3). γ = 72.67(2)°, Z = 2, R = 0.027 for 2527 unique observed reflections.
Accumulation of Volatile Flavour Compounds in Liquid Cultures of Kluyveromyces lactis Strains
Authors: Hanssen Hans-Peter , Sprecher Ewald , Klingenberg Andreas 
Published: February 2017

Abstract
The accumulation of volatile flavour constituents in liquid cultures of three Kluyveromyces lactis strains was studied after cultivation on defined culture media containing glucose as carbon source, yeast extract, vitamines, and different additional nitrogen compounds. Besides short-chain alcohols and esters (fruit esters), 2-phenylethyl alcohol, phenylacetaldehyde, and 2-phenylethyl esters could be identified by gas chromatography and coupled gas chromatography-mass spectrometry. Although the composition of these compounds was qualitatively comparable within the three strains investigated, quantitative differences were significant and strain-dependent reactions to the culture medium could be observed.
The Activity Profile of Elite Male Amateur Boxing After the 2013 Rule Changes
Authors: Davis Philip , Connorton Andrew J. , Driver Sonny , Anderson Sean , Waldock Robert 
Published: February 2017

Abstract
Davis, P, Connorton, AJ, Driver, S, Anderson, S, and Waldock, R. The activity profile of elite male amateur boxing after the 2013 rule changes. J Strength Cond Res 32(12): 3450–3455, 2018—An activity profile of competitive elite amateur boxing after the rule changes in 2013 was created from video footage to allow identification of the technical and tactical demands as well as differences between winners and losers. The study analyzed 50 World Championship bouts involving 60 male boxers (mean ± SD) of age: 23.5 ± 2.8 years, height: 176.2 ± 12.2 cm, and body mass: 71.7 ± 16.2 kg. The results establish that boxing at this level requires the ability to maintain an activity rate of ∼1.55 actions per second, consisting of ∼21 punches, ∼3.6 defensive movements, and ∼56 vertical hip movements all per-minute. Winners had a higher amount of straight punches and straight punches lead hand in round 1 (both p < 0.043) along with total punches landed in round 3 (p = 0.030). They also had a lower ratio of punches thrown to punches landed in round 3 and air punches as a percentage of missed in round 2 and 3 (both p < 0.015). The results suggest that a winning strategy must include the straight punch technique from both lead and rear hands and the ability to increase punching accuracy over subsequent rounds. Tactically, boxing has become long range with straight punches, increased defense and movement around the ring, in contrast to short-range hooks as seen pre-2013. These changes should be considered when creating new training strategies.
Influence of Environmental Conditions on Performance and Heart Rate Responses to the 30-15 Incremental Fitness Test in Rugby Union Athletes
Authors: Natera Alex O.W. , Jennings Jacob , Oakley Aiden J. , Jones Thomas W. 
Published: February 2017

Abstract
Natera, AOW, Jennings, J, Oakley, AJ, and Jones, TW. Influence of environmental conditions on performance and heart rate responses to the 30-15 incremental fitness test in rugby union athletes. J Strength Cond Res 33(2): 486–491, 2019—The purpose of this study was to examine the differences in performance and heart rate (HR) responses between a high heat outdoor condition (34.0° C, 64.1% humidity) and a temperate indoor condition (22.0° C, 50.0% humidity) during the 30-15 intermittent fitness test (30-15IFT). Eight highly trained Rugby Union players (28.1 ± 1.5 years, 181.4 ± 8.8 cm, 88.4 ± 13.3 kg) completed the 30-15IFT in 2 different temperature conditions. Dependent variables recorded and analyzed included: final running speed of the 30-15IFT, HR at rest (HR rest), maximum HR (Max HR), HR recovery, average HR (HR ave), and submaximal HR corresponding to 25, 50, and 75% of final test speed (HR 25%, HR 50%, and HR 75%) and HR at 13 km·h−1 (HR 13 km·h−1). Greater running speeds were achieved when the test was conducted indoors (19.4 ± 0.7 km·h−1 vs. 18.6 ± 0.6 km·h−1, p = 0.002, d = 1.67). Average HR and HR 13 km·h−1 were greater when the test was conducted outdoors (p ≤ 0.05, d > 0.85). Large effect sizes were observed for the greater HR at submaximal intensities (d > 0.90). The results of this study highlight the influence of temperature on 30-15IFT performance and cardiac responses. It is recommended that prescription of training based on 30-15IFT results reflects the temperature that the training will be performed in and that practitioners acknowledge that a meaningful change in assessment results can be the result of seasonal temperature change rather than training-induced change.
Movement Patterns and Muscle Damage During Simulated Rugby Sevens Matches in National Team Players
Authors: Pereira Lucas A. , Nakamura Fábio Y. , Moraes José E. , Kitamura Katia , Ramos Solange P. , Loturco Irineu 
Published: February 2017

Abstract
Pereira, LA, Nakamura, FY, Moraes, JE, Kitamura, K, Ramos, SP, and Loturco, I. Movement patterns and muscle damage during simulated rugby sevens matches in national team players. J Strength Cond Res 32(12): 3465–3474, 2018—The aim of this study was to analyze the match performance (i.e., distance covered in different intensities), signs of muscle damage (assessed by means of creatine kinase [CK] activity and rate of force development [RFD]), and neuromuscular fatigue (using linear sprint and vertical jump performances) after 3 single-day simulated matches performed by rugby sevens players from the Brazilian National team. Ten male rugby sevens players (25.2 ± 3.6 years; 88.7 ± 7.1 kg; 182.2 ± 6.3 cm) participated in this study. On the day before the matches, the athletes performed a 40-m sprint, a vertical jump assessment, and a maximal isometric force test. In the morning of the match day, blood samples were collected to analyze the CK activity. Afterward, 3 simulated rugby sevens' matches were performed with 2-hour intermission periods. The match performance (encompassing total distance and distance covered in different velocity ranges and body loads [BLs]) was obtained from global positioning system units. The statistical analysis was performed using a mixed model approach and the effect sizes (ESs) of the differences. The statistical significance level was set at p ≤ 0.05. Players were capable of maintaining the match performance when comparing the first and last games. Large (ES > 0.8) and significant (p ≤ 0.05) reductions were demonstrated in the total distance and BL when comparing the second with the first halves. Decrements in the explosive force capacity (assessed by means of RFD) and the squat jump (SJ) were noticed (ES varying from 0.55 to 1.14; p ≤ 0.05). The CK activity increased after the matches (ES = 1.29; p ≤ 0.05). The rugby sevens players were able to maintain the physical performance across 3 successive matches simulating the first day of a tournament. The augmented CK activity and the decreases in the SJ and RFD suggest that increased levels of muscle damage were experienced on the day after the matches. Therefore, the technical staff are encouraged to implement recovery strategies and planned substitutions during multiday tournaments to reduce the impact of accumulated fatigue and muscle damage on subsequent match performance. In addition, specific training strategies aimed at better simulating the match demands need to be implemented in the players' training routines.
Manifestations of Proprioception During Vertical Jumps to Specific Heights
Authors: Struzik Artur , Pietraszewski Bogdan , Kawczyński Adam , Winiarski Sławomir , Juras Grzegorz , Rokita Andrzej 
Published: February 2017

AbstractArtur, S, Bogdan, P, Kawczyński, A, Winiarski, S, Grzegorz, J, and Andrzej, R. Manifestations of proprioception during vertical jumps to specific heights.J Strength Cond Res31(6): 1694–1701, 2017—Jumping and proprioception are important abilities in many sports. The efficiency of the proprioceptive system is indirectly related to jumps performed at specified heights. Therefore, this study recorded the ability of young athletes who play team sports to jump to a specific height compared with their maximum ability. A total of 154 male (age: 14.8 ± 0.9 years, body height: 181.8 ± 8.9 cm, body weight: 69.8 ± 11.8 kg, training experience: 3.8 ± 1.7 years) and 151 female (age: 14.1 ± 0.8 years, body height: 170.5 ± 6.5 cm, body weight: 60.3 ± 9.4 kg, training experience: 3.7 ± 1.4 years) team games players were recruited for this study. Each participant performed 2 countermovement jumps with arm swing to 25, 50, 75, and 100% of the maximum height. Measurements were performed using a force plate. Jump height and its accuracy with respect to a specified height were calculated. The results revealed no significant differences in jump height and its accuracy to the specified heights between the groups (stratified by age, sex, and sport). Individuals with a higher jumping accuracy also exhibited greater maximum jump heights. Jumps to 25% of the maximum height were approximately 2 times higher than the target height. The decreased jump accuracy to a specific height when attempting to jump to lower heights should be reduced with training, particularly among athletes who play team sports. These findings provide useful information regarding the proprioceptive system for team sport coaches and may shape guidelines for training routines by working with submaximal loads.
Changes in Vertical and Joint Stiffness in Runners With Advancing Age
Authors: Powell Douglas W. , Williams D.S. Blaise 
Published: February 2017

Abstract
Powell, DW and Williams, DSB. Changes in vertical and joint stiffness in runners with advancing age. J Strength Cond Res 32(12): 3425–3431, 2018—Age-related changes in the neuromuscular system underlie reduced performance and injury but may be mitigated through regular physical activity. It was hypothesized that older (OLD) compared with young (YOUNG) adults would exhibit greater vertical and joint stiffness when running at 3.35 m·s−1. Nine YOUNG and 10 OLD runners performed over ground running trials while three-dimensional biomechanics were recorded. Ankle and knee joint angles, moments and stiffness values were compared between YOUNG & OLD. YOUNG had smaller vertical stiffness (p = 0.01; YOUNG: 32.8 ± 3.6; OLD: 38.1 ± 5.7) and greater joint stiffness than OLD at the ankle (p = 0.04; YOUNG: 0.134 ± 0.021; OLD: 0.118 ± 0.017) and knee (p = 0.01; YOUNG: 0.119 ± 0.016; OLD: 0.098 ± 0.014). YOUNG exhibited greater peak knee flexion angles (p = 0.04; YOUNG: 43.4 ± 6.5°; OLD: 39.1 ± 2.6°), and peak ankle plantarflexion (p = 0.02; YOUNG: −2.8 ± 0.4 Nm·kg−1; OLD: −2.5 ± 0.1 Nm·kg−1) and knee extension moments (p < 0.01; 2.6 ± 0.3 Nm·kg−1; OLD: 2.1 ± 0.2 Nm·kg−1) than OLD whereas no differences were observed in peak ankle dorsiflexion angles (p = 0.44; YOUNG: 23.6 ± 4.2°; OLD: 23.4 ± 2.1°). The findings of this study suggest that OLD compared with YOUNG adults adopt altered lower extremity biomechanics. These altered running biomechanics by seek to minimize the metabolic cost of running or may be a function of reduced lower extremity strength and power.
Intermittent but Not Continuous Static Stretching Improves Subsequent Vertical Jump Performance in Flexibility-Trained Athletes
Authors: Bogdanis Gregory C. , Donti Olyvia , Tsolakis Charilaos , Smilios Ilias , Bishop David J. 
Published: February 2017

Abstract
Bogdanis, GC, Donti, O, Tsolakis, C, Smilios, I, and Bishop, DJ. Intermittent but not continuous static stretching improves subsequent vertical jump performance in flexibility-trained athletes. J Strength Cond Res 33(1): 203–210, 2019—This study examined changes in countermovement jump (CMJ) height after an intermittent or a continuous static stretching protocol of equal total duration. Sixteen male, elite-level gymnasts performed 90 seconds of intermittent (3 × 30 seconds with 30 seconds rest) or continuous stretching (90 seconds) of the quadriceps muscle. A single-leg stretching and jumping design was used, with the contralateral limb serving as a control. The same individuals performed both conditions with alternate legs in a randomized, counterbalanced order. One-leg CMJ height was measured for the stretched and the control leg after warm-up, immediately after stretching, and at regular intervals for 10 minutes after stretching. Range of motion (ROM) of the hip and knee joints was measured before, after, and 10 minutes poststretching. Compared with the control leg, intermittent stretching increased CMJ height by 8.1 ± 2.0%, 4 minutes into recovery (2.2 ± 2.0 cm, 95% confidence interval [CI]: 1.0–3.4 cm, p = 0.001), whereas continuous stretching decreased CMJ height by 17.5 ± 3.3% immediately after (−2.9 ± 1.7 cm, 95% CI: −2.0 to −3.7 cm, p = 0.001) and by 12.0 ± 2.7% 1 minute after stretching (−2.2 ± 2.1 cm, 95% CI: −1.2 to −3.2 cm, p = 0.001). The increases in hip (2.9 and 3.6°, p = 0.001. d = 2.4) and knee joint ROM (5.1 and 6.1°, p = 0.001. d = 0.85) after the intermittent and continuous stretching protocols were not different. The opposite effects of intermittent vs. continuous stretching on subsequent CMJ performance suggests that stretching mode is an important variable when examining the acute effects of static stretching on performance in flexibility-trained athletes.
Effects of Exercise Induced Dehydration and Glycerol Rehydration on Anaerobic Power in Male Collegiate Wrestlers
Authors: McKenna Zachary J. , Gillum Trevor L. 
Published: February 2017

Abstract
McKenna, ZJ and Gillum, TL. Effects of exercise induced dehydration and glycerol rehydration on anaerobic power in male collegiate wrestlers. J Strength Cond Res 31(11): 2965–2968, 2017—Wrestlers attempting to reach a specific weight class often use rapid weight loss (RWL). Rapid weight loss is associated with high levels of dehydration, which may hinder athletic performance. Thus, there is a need for wrestlers to optimize rehydration after achieving a specific weight. We sought to observe the effects of RWL on anaerobic power and the impact of glycerol on rehydration and power in male collegiate wrestlers (n = 7, 19.75 ± 1.67 years, 76.8 ± 4.32 kg, 11.6 ± 4.32% body fat, 59.9 ± 6.42 ml·kg−1·min−1). Subjects were assessed for body mass (BM), hydration, and mean power output (Wmean) before exercise (pre), immediately after exercise (3% dehydrated), and 60 minutes after exercise (rehydrated). Participants ran at 70% of V̇o
2max in a heated room (30° C) until 3% BM loss (BML). Subjects rehydrated drinking either 26 ml·kg−1 of water (control) or a 3% glycerol (treatment) solution containing 26 ml·kg−1 of water and 1 g·kg−1 of glycerol. Participants lost 3.00 ± 0.31% (control) and 2.89 ± 0.26% (treatment) of their BM from the pre- to dehydrated conditions. Wmean (control: 659.29 ± 79.12, 651.43 ± 70.71, 659.71 ± 82.78; treatment: 647.71 ± 110.64, 644.57 ± 118.15, 638.14 ± 100.71) did not differ across time (p = 0.87) nor condition (p = 0.80). In addition, glycerol had no significant impact on acute hydration (control: urine-specific gravity [SG] = 1.019 ± 0.010; treatment: SG = 1.017 ± 0.017). These data show that 3% BML did not impair anaerobic performance, and furthermore that glycerol proved ineffective for rehydration in a match like scenario for the competing wrestler.
Comparison of Different Methods for the Swimming Aerobic Capacity Evaluation
Authors: Pelarigo Jailton G. , Fernandes Ricardo J. , Ribeiro João , Denadai Benedito S. , Greco Camila C. , Vilas-Boas João P. 
Published: February 2017

Abstract
Pelarigo, JG, Fernandes, RJ, Ribeiro, J, Denadai, BS, Greco, CC, and Vilas-Boas, JP. Comparison of different methods for the swimming aerobic capacity evaluation. J Strength Cond Res 32(12): 3551–3560, 2018—This study compared velocity (v) and bioenergetical factors using different methods applied for the swimming aerobic capacity evaluation. Ten elite female swimmers (17.6 ± 1.9 years, 1.70 ± 0.05 m, and 61.3 ± 5.8 kg) performed an intermittent incremental velocity protocol until voluntary exhaustion to determine the v associated with the individual anaerobic threshold (IAnT), ventilatory threshold (VT), heart rate threshold (HRT), lactate threshold fixed in 3.5 mmol·L−1 (LT3.5), and maximal oxygen uptake (V̇O2max). Two-to-three 30-minute submaximal constant tests for the v assessment at maximal lactate steady state (MLSS). The v, gas exchange, heart rate, and blood lactate concentration variables were monitored in all tests. The values of all parameters at the v corresponding to MLSS, IAnT, VT, and HRT were similar (p ≤ 0.05), with high agreement (r
2 > 0.400), except for carbon dioxide (V̇CO2) that was higher for MLSS compared with VT (p ≤ 0.05). However, the v at LT3.5 was higher when compared with other methods for v and bioenergetical factors. It is suggested that IAnT, VT, and HRT methods are better predictors of the intensity corresponding to the commonly accepted gold-standard method (i.e., MLSS) for the aerobic capacity evaluation compared with LT3.5.