Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields.

Kilowatt-class high-energy frequency conversion to 95 J at 10 Hz at 515 nm

We report on frequency doubling of high-energy,high repetition rate ns pulses from a cryogenically gas cooled multi-slab ytterbium-doped yttrium aluminum garnet laser system,Bivoj/DiPOLE,using a type-I phase matched lithium triborate crystal.We achieved conversion to 515 nm with energy of 95 J at repetition rate of 10 Hz and conversion efficiency of 79%.High conversion efficiency was achieved due to successful depolarization compensation of the fundamental input beam.

Optically monitoring and controlling nanoscale topography during semiconductor etching

We present epi-diffraction phase microscopy(epi-DPM)as a non-destructive optical method for monitoring semiconductor fabrication processes in real time and with nanometer level sensitivity.The method uses a compact Mach–Zehnder interferometer to recover quantitative amplitude and phase maps of the field reflected by the sample.The low temporal noise of 0.6 nm per pixel at 8.93 frames per second enabled us to collect a three-dimensional movie showing the dynamics of wet etching and thereby accurately quantify non-uniformities in the etch rate both across the sample and over time.By displaying a gray-scale digital image on the sample with a computer projector,we performed photochemical etching to define arrays of microlenses while simultaneously monitoring their etch profiles with epi-DPM.

Development of a 100 J,10 Hz laser for compression experiments at the High Energy Density instrument at the European XFEL

In this paper we review the design and development of a 100 J, 10 Hz nanosecond pulsed laser, codenamed DiPOLE100 X,being built at the Central Laser Facility(CLF). This 1 kW average power diode-pumped solid-state laser(DPSSL) is based on a master oscillator power amplifier(MOPA) design, which includes two cryogenic gas cooled amplifier stages based on DiPOLE multi-slab ceramic Yb:YAG amplifier technology developed at the CLF. The laser will produce pulses between 2 and 15 ns in duration with precise, arbitrarily selectable shapes, at pulse repetition rates up to 10 Hz, allowing real-time shape optimization for compression experiments. Once completed, the laser will be delivered to the European X-ray Free Electron Laser(XFEL) facility in Germany as a UK-funded contribution in kind, where it will be used to study extreme states of matter at the High Energy Density(HED) instrument.

Pushing the boundaries of diode-pumped solid-state lasers for high-energy applications

We report on the successful demonstration of a 150 J nanosecond pulsed cryogenic gas cooled,diode-pumped multi-slab Yb:YAG laser operating at 1 Hz.To the best of our knowledge,this is the highest energy ever recorded for a diodepumped laser system.