741 research outputs found
PREPARATION AND EVALUATION OF EXTENDED RELEASE NIMESULIDE TABLET BASED ON DIFFUSION CONTROLLED MECHANISM
Now a days the concept of controlled release is quiet popular amongst the formulation scientists. The aim of thisstudy was to develop a once-daily sustained release matrix tablet of Nimesulide using hydroxyl propylmethylcellulose (HPMC K4M) as release controlling factor and to evaluate drug release parameters as per variousrelease kinetic models. The tablets were prepared using wet granulation method. Total of five batches were preparedfrom which two selected batches were further evaluated. Different dissolution models were applied to drug releasedata in order to evaluate release mechanisms and kinetics. The “n” Value of both batches indicates that the drugrelease mechanism follows “Anomalous Transport”. From all these data it is quite clear that batch F2 is optimized asits release kinetic was found to be as per Korsmeyer Peppas model rather than first order of F4
Spectral analysis of molecular resonances in erbium isotopes: Are they close to semi-Poisson?
We perform a thorough analysis of the spectral statistics of experimental
molecular resonances, of bosonic erbium Er and Er isotopes,
produced as a function of magnetic field() by Frisch et al. [Nature 507,
(2014) 475], utilizing some recently derived surmises which interpolate between
Poisson and GOE and without unfolding. Supplementing this with an analysis
using unfolded spectrum, it is shown that the resonances are close to
semi-Poisson distribution. There is an earlier claim of missing resonances by
Molina et al. [Phys. Rev. E 92, (2015) 042906]. These two interpretations can
be tested by more precise measurements in future experiments.Comment: 7 pages, 6 figure
Test–retest reliability of the magnitude and direction of asymmetry in the countermovement jump, drop jump, and countermovement rebound jump
This study aimed to investigate the test–retest reliability of three bilateral jump tests to assess asymmetry and determine the consistency of both the magnitude and direction of asymmetry between two testing sessions. Thirty-three participants performed the countermovement jump (CMJ), drop jump (DJ), and countermovement rebound jump (CMRJ—jump 1: CMRJ1; jump 2: CMRJ2) over two sessions. Inter-limb asymmetry was calculated for kinetic metrics, including the mean propulsive force, net braking impulse, and net propulsive impulse. Test reliability was computed using intraclass correlation coefficients (ICC), coefficients of variation (CV), and standard error of measurement. Furthermore, analysis of variance was used to determine the systematic bias between jump types and sessions. Kappa coefficients were utilised to assess the consistency of asymmetry favouring the same limb. Results showed poor to excellent reliability for all jump tests between sessions (ICC range = 0.19–0.99, CV range = 2.80–11.09%). A significantly higher magnitude of asymmetry was revealed for the net braking impulse during the DJ compared to the CMRJ2 (p ≥ 0.014, g ≤ 0.53). When computing the direction of asymmetry between test sessions, Kappa coefficients revealed that levels of agreement were substantial (Kappa = 0.63–0.70) for the CMJ, moderate to almost perfect (Kappa = 0.59–0.94) for the CMRJ1, moderate to almost perfect (Kappa = 0.58–0.81) for the DJ, and slight to moderate for the CMRJ2 (Kappa = 0.19–0.57). These results underscore the variable nature of both the magnitude and direction of asymmetry during jump testing. Thus, practitioners should carefully choose evaluation methods and metrics characterised by low variability to ensure robust asymmetry assessments
Effects of concurrent activation potentiation on countermovement jump performance
The purpose of this study was to assess the effects of concurrent activation potentiation (CAP) on countermovement jump (CMJ) performance. Twenty-four resistance trained males (mean ± SD, age 25 ± 4 years; body mass: 78.7 ± 10.3 kg) performed a CMJ on a force plate under four different conditions: a) a control condition where the CMJ was performed with hands on hips and lips pursed, thus preventing jaw or fist contraction from occurring, b) a jaw condition where the CMJ was performed with maximal contraction of the jaw, c) a fist condition where the CMJ was performed with maximal contraction of the fists, and d) a combined condition where the CMJ was performed with maximal contraction of both jaw and fists. Jump height (JH), peak force (PF), rate of force development (RFD) and time to peak force (TTPF) were calculated from the vertical force trace. There was no significant difference in PF (P = 0.88), TTPF (P = 0.96), JH (P = 0.45), or RFD (P = 0.06) between the four conditions. Effect size (ES) comparisons suggests a potential for the BOTH condition to augment both PF (2.4%; ES: 0.62) and RFD (9.9%; ES: 0.94) over NORM. It is concluded that CAP via singular and combined contractions has no significant impact on CMJ performance, however, substantial inter-individual variation in the response to CAP was observed and such techniques may therefore warrant consideration on an individual basis
Physical characteristics underpinning lunging and change of direction speed in fencing
Lunge velocity (LV) and change of direction speed (CODS) are considered fundamental to success during fencing competitions; investigating the physical characteristics that underpin these is the aim of this study. Seventy fencers from the British Fencing National Academy took part and on average (± SD) were 16.83 ± 1.72 years of age, 178.13 ± 8.91 cm tall, 68.20 ± 9.64 kg in mass and had 6.25 ± 2.23 years fencing experience. The relationship between anthropometric characteristics (height, arm-spam and adductor flexibility) and measures of lower-body power (bilateral and unilateral countermovement jump height and reactive strength index) were examined in their ability to influence LV and CODS. In testing the former, fencers lunged (over a self-selected distance) to and from a force plate, where front leg impact and rear leg propulsive force was quantified; the lunging distance was
divided by time to establish LV. CODS was measured over 12 m involving shuttles of between 2 and 4 m. Results revealed that LV and CODS averaged at 3.35 m/s and 5.45 s respectively and in both cases, standing broad jump was the strongest predictor
(r = 0.51 and -0.65 respectively) of performance. Rear leg drive and front leg impact force averaged at 14.61 N/kg and 3-times bodyweight respectively, with single leg jumps revealing an asymmetry favoring the front leg of 9%. In conclusion, fencers
should train lower-body power emphasizing horizontal displacement, noting that this seems to offset any advantage one would expect fencers of a taller stature to have. Also, the commonly reported asymmetry between legs is apparent from adolescence and thus also requires some attention
Heavy barbell hip thrusts do not effect sprint performance: an 8-week randomized–controlled study
The purpose of this study was to examine the effects of an 8-week barbell hip thrust strength training program on sprint performance. Twenty-one collegiate athletes (15 males and 6 females) were randomly assigned to either an intervention (n = 11, age 27.36 ± 3.17 years, height 169.55 ± 10.38 cm, weight 72.7± 18 kg) or control group (n = 10, age 27.2 ± 3.36 years, height 176.2 ± 7.94 cm, weight 76.39 ± 11.47 kg). 1RM hip thrust, 40m sprint time, and individual 10m split timings: 0-10, 10-20, 20-30, 30-40m, were the measured variables; these recorded at both the baseline and post testing time points. Following the 8-week hip thrust strength training intervention significantly greater 1RM hip thrust scores for the training group were observed (p 0.05, r = 0.05 – 0.37). No significant differences were seen for the control group for 1RM hip thrust (p = 0.106, d = 0.24 [mean difference 9.4 kg]) or sprint time (all sprint performance measures: p > 0.05, r = 0.13 – 0.47). These findings suggest that increasing maximum hip thrust strength through use of the barbell hip thrust does not appear to transfer into improvements in sprint performance in collegiate level athletes
Weightlifting: an applied method of technical analysis
Weightlifting is a highly technical sport which is governed by interactions of phases to optimise the load lifted. Given the technicality of the snatch and clean and jerk, understanding key stable components to identify errors and better prescribe relevant exercises are warranted. The aim of this article is to present an applied method of analysis for coaches that considers the biomechanical underpinnings of optimal technique through stable interactions of the kinetics and kinematics of the lifter and barbell at key phases of the lift. This paper will also look to discuss variable components which may differentiate between athletes and therefore provide a foundation in what to identify when coaching weightlifting to optimise load lifted whilst allowing for individual variances
Dynamics of order-disorder and complexity for interacting bosons in optical lattice
The present work reports on the dynamical measures of order, disorder and
complexity for the interacting bosons in optical lattice. We report results
both for the relaxed state as well as quench dynamics. Our key observations
are: (1) Lattice depth can be taken as order-disorder parameter. (2) The
superfluid to Mott insulator transition can be treated as `order-disorder'
transition. Our main motivation is to find how the system organize by itself
during quench and how it optimizes the complexity. We find dynamical measures
of order and disorder are more sensitive tool than entropy measures. We
specifically calculate the time scale of entry and exit of different phases
during time evolution. Initially the system exhibits collapse revival trend,
however gradually looses its ability to turn back to superfluid phase and
finally Settle to Mott insulator phase.Comment: 9 pages, 5 figure
Bivariate -distribution for transition matrix elements in Breit-Wigner to Gaussian domains of interacting particle systems
Interacting many-particle systems with a mean-field one body part plus a
chaos generating random two-body interaction having strength , exhibit
Poisson to GOE and Breit-Wigner (BW) to Gaussian transitions in level
fluctuations and strength functions with transition points marked by
and , respectively; . For these systems theory for matrix elements of one-body transition
operators is available, as valid in the Gaussian domain, with , in terms of orbitals occupation numbers, level densities and an
integral involving a bivariate Gaussian in the initial and final energies. Here
we show that, using bivariate -distribution, the theory extends below from
the Gaussian regime to the BW regime up to . This is well
tested in numerical calculations for six spinless fermions in twelve single
particle states.Comment: 7 pages, 2 figure
Do fencers require a weapon-specific approach to strength and conditioning training?
There are three types of weapon used in Olympic fencing: the foil, épée and sabre. The aim of this study was to determine if fencers exhibited different physical characteristics across weapons. Seventy-nine male (n = 46) and female (n = 33) national standard fencers took part in this study. Fencers from each weapon (male and female), i.e., épée (n = 19 and 10), foil (n = 22 and 14) and sabre (n = 13 and 10) were (mean ± SD) 15.9 ± 0.7 years of age, 178.5 ± 7.9 cm tall, 67.4 ± 12.2 kg in mass and had 6.3 ± 2.3 years fencing experience; all were in regular training (~ 4 times per week). Results revealed that across all performance tests (lower body power, reactive strength index, change of direction speed and repeat lunge ability) there was no significant difference between weapons (p = 3.66). Differences were found however, when comparing genders, with males performing significantly better during the countermovement jump (p = 0.001), reactive strength index (p = 0.002), change of direction speed (p < 0.001) and repeat lunge ability (p < 0.001). The former findings may be due to similarities in bout intensity and time, movement types (lunging and changing direction) and the need to execute competition actions as explosively as possible. Based on the findings of the current study, it could be indicated that épée, foil and sabre fencers do not require a weapon specific approach to strength and conditioning training. Each fencer should target the area they are weakest at, rather than the area that they feel best represents the unique demands of their weapon
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