Read by QxMD icon Read

high jump

U Buchenau
The highly viscous flow is due to thermally activated Eshelby transitions which transform a region of the undercooled liquid to a different structure with a different elastic misfit to the viscoelastic surroundings. A self-consistent determination of the viscosity in this picture explains why the average structural relaxation time is a factor of eight longer than the Maxwell time. The physical reason for the short Maxwell time is the very large contribution of strongly strained inherent states to the fluidity (the inverse viscosity)...
February 14, 2018: Journal of Chemical Physics
Yihua Ren, Wei Cui, Shuiqing Li
We report an electrohydrodynamic instability in a premixed stagnation flame under manipulations of a dc electric field. This instability occurs when the electric field strength is at a certain value below the breakdown threshold, which is 0.75 kV/cm in the experimental setup. Above this value the flame front suddenly transits from a substrate-stabilized near-flat shape to a nozzle-stabilized conical surface, accompanied by a jump in the electric current through the flame field. At the transition moment, the flame spontaneously propagates upstream to the nozzle while the flow velocity at the upstream of the flame front decreases to zero, as revealed by high-speed photographs and PIV measurements...
January 2018: Physical Review. E
Alain de Cheveigné, Dorothée Arzounian
Electroencephalography (EEG), magnetoencephalography (MEG) and related techniques are prone to glitches, slow drift, steps, etc., that contaminate the data and interfere with the analysis and interpretation. These artifacts are usually addressed in a preprocessing phase that attempts to remove them or minimize their impact. This paper offers a set of useful techniques for this purpose: robust detrending, robust rereferencing, outlier detection, data interpolation (inpainting), step removal, and filter ringing artifact removal...
February 12, 2018: NeuroImage
Knut Thomas Schneiker, Jackson James Fyfe, Francois Billaut, David John Bishop
PURPOSE: The effectiveness of contrast training (CST) for improving explosive exercise performance is modulated by various individual characteristics; however, further work is required to define these factors. METHODS: Sub-elite male Australian Football players [n = 22; age, 19 ± 2 y; body mass, 80.4 ± 9.4 kg; one-repetition maximum (1-RM) half squat, 172 ± 18 kg; mean ± SD] completed two experimental trials involving two sets of squat jumps (6 repetitions at 30% 1-RM) performed either alone (CTL condition) or after half squats (6 repetitions at 85% 1-RM; CST condition)...
February 13, 2018: Medicine and Science in Sports and Exercise
Sebastian Tomescu, Ryan Bakker, Tyson A C Beach, Naveen Chandrashekar
Estimation of muscle forces through musculoskeletal simulation is important in understanding human movement and injury. Unmatched filter frequencies used to low-pass filter marker and force platform data can create artifacts during inverse dynamics analysis, but their effects on muscle force calculations are unknown. The objective of this study was to determine the effects of filter cutoff frequency on simulation parameters and magnitudes of lower extremity muscle and resultant joint contact forces during a high-impact maneuver...
February 12, 2018: Journal of Applied Biomechanics
Athanasios Chatzinikolaou, Konstantinos Michaloglou, Alexandra Avloniti, Diamanda Leontsini, Chariklia K Deli, Dimitris Vlachopoulos, Luis Gracia-Marco, Sotirios Arsenis, Ioannis Athanailidis, Dimitrios Draganidis, Athanasios Z Jamurtas, Craig A Williams, Ioannis G Fatouros
PURPOSE: Τo investigate the effect of a complex, short-term strength/power training protocol on performance and body composition of elite early-adolescent soccer players. METHODS: Twenty-two players (14-15 years) were randomly assigned to (a) an experimental (EG, n=12, participated in a 5-week training protocol with traditional multi-joint power resistance exercises, Olympic-style lifts, plyometric drills and speed work, four times/week) or (b) a control group (CG, n=10)...
February 12, 2018: International Journal of Sports Physiology and Performance
Mathieu Lacome, Christopher Carling, Jean-Philippe Hager, Gerard Dine, Julien Piscione
PURPOSE: This study examined the effects of an intensified tournament on workload, perceptual and neuromuscular fatigue and muscle damage responses in an international under-20 rugby union team. METHODS: Players were subdivided into two groups according to match-play exposure time: high (HEG, n=13) and low (LEG, n=11). Measures monitored over the 19-day period included training session (n=10) and match (n=5) workload determined via global positioning systems and session ratings of perceived exertion (sRPE)...
February 12, 2018: International Journal of Sports Physiology and Performance
Rosario Martínez-Herrero, David Maluenda, Ignasi Juvells, Artur Carnicer
We introduce a new method for producing optical needles with tunable length and almost constant irradiance based on the evaluation of the on-axis power content of the light distribution at the focal area. According to theoretical considerations, we propose an adaptive modulating continuous function that presents a large derivative and a zero value jump at the entrance pupil of the focusing system. This distribution is displayed on liquid crystal devices using holographic techniques. In this way, a polarized input beam is shaped and subsequently focused using a high numerical aperture (NA) objective lens...
February 8, 2018: Scientific Reports
Anh D Phan, Kenneth S Schweizer
We generalize the force-level, microscopic, Nonlinear Langevin Equation (NLE) theory and its elastically collective generalization [elastically collective nonlinear Langevin equation (ECNLE) theory] of activated dynamics in bulk spherical particle liquids to address the influence of random particle pinning on structural relaxation. The simplest neutral confinement model is analyzed for hard spheres where there is no change of the equilibrium pair structure upon particle pinning. As the pinned fraction grows, cage scale dynamical constraints are intensified in a manner that increases with density...
February 7, 2018: Journal of Chemical Physics
Olivier Navaud, Adelin Barbacci, Andrew Taylor, John P Clarkson, Sylvain Raffaele
The range of hosts that a parasite can infect in nature is a trait determined by its own evolutionary history and that of its potential hosts. However, knowledge on host range diversity and evolution at the family level is often lacking. Here, we investigate host range variation and diversification trends within the Sclerotiniaceae, a family of Ascomycete fungi. Using a phylogenetic framework, we associate diversification rates, the frequency of host jump events, and host range variation during the evolution of this family...
February 8, 2018: Molecular Ecology
Ana Luiza Matias Correia, Filipe Dinato de Lima, Martim Bottaro, Amilton Vieira, Andrew Correa da Fonseca, Ricardo M Lima
The purpose of this study was to investigate the effects of a single-dose of β-hydroxy-β-methylbutyrate free acid (HMB-FA) supplementation on muscle recovery after a high-intensity exercise bout. Twenty-three trained young males were randomly assigned to receive either a single-dose supplementation of 3g of HMB-FA (n = 12; age 22.8 ± 3.0 years) or placebo (PLA; n = 11; age 22.9 ± 3.1 years). A muscle damage protocol was applied 60 minutes after supplementation, and consisted of seven sets of 20 drop jumps from a 60-cm box with 2-min rest intervals between sets...
February 8, 2018: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Dionysia Aravopoulou, Konstantinos Kyriakos, Anna Miasnikova, André Laschewsky, Christine M Papadakis, Apostolos Kyritsis
The thermoresponsive behavior of two diblock copolymers PS-b-PNIPAM and PS-b-PMDEGA, which both comprise a hydrophobic polystyrene block but different thermoresponsive blocks, also differing in length, poly(N-isopropylacrylamide) (PNIPAM) and poly(methoxy diethylene glycol acrylate) (PMDEGA), respectively, was comparatively investigated in a wide temperature range. Concentrated aqueous solutions containing 25 wt% polymer, were studied by small-angle X-ray scattering (SAXS), differential scanning calorimetry (DSC) and broadband dielectric spectroscopy (BDS)...
February 8, 2018: Journal of Physical Chemistry. B
Richard Busch, Michael Krause, Steve Coyle, Thomas Höche
Glancing-angle Ar+ broad ion beam erosion is widely used for the preparation of high-quality transmission electron microscopy (TEM) samples. However, low erosion rates and lack of site specificity are major drawbacks of the method. Being inexpensive and easy to use - in particular when compared to widely used focused ion beam preparation methods - overcoming these drawbacks would significantly improve many existing preparation workflows. We present a novel method for rapid and localized surface erosion which combines laser-machining preprocessing with broad ion beam etching...
January 31, 2018: Micron: the International Research and Review Journal for Microscopy
John J McMahon, Timothy J Suchomel, Jason P Lake, Paul Comfort
Two reactive strength index (RSI) variants exist, the RSI and RSI modified (RSImod) which are typically calculated during the drop jump (DJ) and countermovement jump (CMJ), respectively. Both RSI variants have been used to monitor athletes' ability to complete stretch-shortening cycle actions quickly, but they have never been compared. The purpose of this study was to determine if they yield relatable information about reactive strength characteristics. Male professional rugby league players (n = 21, age = 20...
February 1, 2018: Journal of Strength and Conditioning Research
Anthony M J Sanchez, Fabio Borrani
This study exanimated the effects of intermittent hypoxic training (IHT) conducted at a high level of hypoxia with recovery at ambient air on aerobic/anaerobic capacities at sea level and hematological variations. According to a double-blind randomized design, fifteen highly endurance-trained runners completed a 6-weeks regimented training with 3 sessions per week consisting of intermittent runs (6x work-rest ratio of 5':5') on a treadmill at 80-85% of maximal aerobic speed ([Formula: see text]). Nine athletes (hypoxic group, HG) performed the exercise bouts at FI02 = 10...
February 2, 2018: Journal of Sports Sciences
Todd J Leutzinger, Zachary M Gillen, Amelia M Miramonti, Brianna D McKay, Alegra I Mendez, Joel T Cramer
The purpose of the present study was to investigate differences among player positions at three grade levels in elite, collegiate-prospective American football players. Participants' data (n = 7,160) were analyzed for this study [mean height (Ht) ± standard deviation (SD) = 178 ± 7 cm, weight (Wt) = 86 ± 19 kg]. Data were obtained from 12 different high school American football recruiting combines hosted by Zybek Sports (Boulder, Colorado). Eight two-way (9x3) mixed factorial ANOVAs [position (defensive back (DB), defensive end (DE), defensive lineman (DL), linebacker (LB), offensive lineman (OL), quarterback (QB), running back (RB), tight end (TE), and wide receiver (WR) x grade (freshmen, sophomores, and juniors)] were used to test for differences among the mean test scores for each combine measure [Ht, Wt, 40-yard (40yd) dash, pro-agility drill (PA), L-cone drill (LC), vertical jump (VJ), and broad jump (BJ)]...
January 30, 2018: Journal of Strength and Conditioning Research
Deniz Balci, Menekse Ozcelik, Elvan Onur Kirimker, Arda Cetinkaya, Evren Ustuner, Mehmet Cakici, Bahadir Inan, Zekeriyya Alanoglu, Sadik Bilgic, Ahmet Ruchan Akar
BACKGROUND: Liver resection for intrahepatic cholangiocarcinoma (ICC) with invasion of the inferior vena cava (IVC) and hepatic veins (HV) is a challenging procedure. CASE PRESENTATION: We report a case of a 63-year-old woman with a 6-cm, centrally located liver mass. Her biochemistry results were normal except for a Ca19-9 level of 1199 U/ml. The liver biopsy was consistent with ICC and 60% macrosteatosis. Abdominal CT scans revealed a large central mass invading the left HV, middle HV and right HV, infringing on their junction with the vena cava...
January 31, 2018: BMC Surgery
Víctor Rouco, Davide Massarotti, Daniela Stornaiuolo, Gian Paolo Papari, Xavier Obradors, Teresa Puig, Francesco Tafuri, Anna Palau
High-resolution focused ion beam lithography has been used to fabricate YBa₂Cu₃O7-x (YBCO) wires with nanometric lateral dimensions. In the present work, we investigate Flux-flow instabilities in nanowires of different widths, showing sudden voltage switching jumps from the superconducting to the normal state. We present an extensive study on the temperature and field dependence of the switching characteristics which reveal that voltage jumps become less abrupt as the temperature increases, and disappear at the vortex-liquid state...
January 30, 2018: Materials
Cheng-Chen Hsu, Tsorng-Harn Fong, Hung-Ming Chang, Borcherng Su, Chung-Pu Chi, Nai-Wen Kan, Mei-Chich Hsu
A recent study reported that lower limb explosive power had no correlation with the 2D:4D ratio. However, many studies hypothesized that a lower 2D:4D ratio (reflecting a relative higher testosterone exposure) predicts higher physical fitness. The aim of this study is to replicate the study of explosive power and the 2D:4D ratio in a sample of Taiwanese children. A total of 541 Taiwanese prepubertal children (257 girls and 284 boys aged 9-10 years) participated in this study. This study analyzed the relationship between the 2D:4D ratio and explosive power...
January 29, 2018: Journal of Strength and Conditioning Research
Christopher J Clark, Jimmy A McGuire, Elisa Bonaccorso, Jacob S Berv, Richard O Prum
Phenotypic characters with a complex physical basis may have a correspondingly complex evolutionary history. Males in the 'bee' hummingbird clade court females with sound from tail-feathers, which flutter during display dives. On a phylogeny of 35 species, flutter sound frequency evolves as a gradual, continuous character on most branches. But on at least six internal branches fall two types of major, saltational changes: mode of flutter changes, or the feather that is the sound source changes, causing frequency to jump from one discrete value to another...
January 29, 2018: Evolution; International Journal of Organic Evolution
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"