1,795 research outputs found
Ultrasonic tomographic imaging of defects in industrial materials
Ultrasonic tomography has been fairly widely applied for imaging of inhomogeneities in isotropic materials, particularly in the medical field, however, little success has been made in its application to industrial materials. This is largely due to the complex nature of ultrasonic wave propagation in these anisotropic materials. The three dimensional characteristics of ultrasonic wave propagation in anisotropic materials have been thoroughly studied for single crystals and also studied recently for different composites [1,2,3]. Understanding these characteristics provides the theoretical background for developing appropriate ultrasonic tomographic imaging methods for industrial materials
Cross-correlation analysis to quantify relative spatial distributions of fat and protein in super-resolution microscopy images of dairy gels
The advent of super-resolution microscopy allows microstructures of foods to be explored in new depths, which when coupled with quantitative image analysis can provide a powerful analytical tool. Herein, a methodology is presented and applied to use a 2D spatial cross-correlation analysis to investigate the relative spatial arrangement of protein and fat in acid induced whole milk gels where the milk is either non-homogenised or has been homogenised at either 10 or 25 MPa. Two-channel images were taken using super-resolution Stimulated Emission Depletion (STED) microscopy and confocal microscopy. A term has been derived to extract the typical distance from the fat droplet surface and to the local maximum protein distribution. The fat droplet size is determined through 2D spatial autocorrelation analysis. Methods of analysis are applied to global images and to region specific analysis focussing on individual fat droplets. Cross-correlation analysis has been empirically validated using generated images with precise spatial features corresponding to the features of interest in true microscopy images, over appropriate length scales. The protein microstructure, fat droplet size and distances between the fat droplets and protein network are characterised. There are significantly different distances between the fat droplets and protein network in the homogenised samples compared to the non-homogenised sample. The extracted separation distances are below the diffraction limit of light, highlighting the utility of super-resolution imaging
Acute Effects of Barbell Bouncing and External Cueing on Power Output in Bench Press Throw in Resistance-Trained Men.
The aims of this study were to compare power output during a bench press throw (BPT) executed with (BPT(bounce)) and without (BPT) the barbell bounce technique, and examine the effect of cueing different barbell descent velocities on BPT power output in resistance-trained males. In total, 27 males (age 23.1 ± 2.1 years; body mass 79.4 ± 7.4 kg; height 178.8 ± 5.5 cm; and 4.6 ± 1.9 years of resistance training experience) were recruited and attended one familiarization session and two experimental sessions (EXP 1 and EXP 2). The force–velocity profile during maximal BPT and BPT(bounce) (randomized order) under different loads (30–60 kg) was established (EXP 1), and the effect of varying external barbell descent velocity cues “slow, medium, and as fast as possible” (i.e., “fast”) on the power output for each technique (BPT and BPT(bounce)) was examined (EXP 2). Comparing two BPT techniques (EXP 1), BPT(bounce) demonstrated 7.9–14.1% greater average power (p ≤ 0.001, ES = 0.48–0.90), 6.5–12.1% greater average velocity (p ≤ 0.001, ES = 0.48–0.91), and 11.9–31.3% shorter time to peak power (p ≤ 0.001–0.05, ES = 0.33–0.83) across the loads 30–60 kg than BPT. The cueing condition “fast” (EXP 2) resulted in greater power outcomes for both BPT and BPT(bounce) than “slow.” No statistically significant differences in any of the power outcomes were observed between “medium” and “slow” cuing conditions for BPT (p = 0.097–1.000), whereas BPT(bounce) demonstrated increased average power and velocity under the “medium” cuing condition, compared to “slow” (p = 0.006–0.007, ES = 0.25–0.28). No statistically significant differences were observed in barbell throw height comparing BPT and BPT(bounce) under each cuing condition (p = 0.225–1.000). Overall, results indicate that both bouncing the barbell and emphasizing barbell descent velocity be considered to improve upper body power in athlete and non-athlete resistance-training programs
Imaging calcium in drosophila at egg activation
© 2016 Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.Egg activation is a universal process that includes a series of events to allow the fertilized egg to complete meiosis and initiate embryonic development. One aspect of egg activation, conserved across all organisms examined, is a change in the intracellular concentration of calcium (Ca2+) often termed a 'Ca2+ wave'. While the speed and number of oscillations of the Ca2+ wave varies between species, the change in intracellular Ca2+ is key in bringing about essential events for embryonic development. These changes include resumption of the cell cycle, mRNA regulation, cortical granule exocytosis, and rearrangement of the cytoskeleton. In the mature Drosophila egg, activation occurs in the female oviduct prior to fertilization, initiating a series of Ca2+-dependent events. Here we present a protocol for imaging the Ca2+ wave in Drosophila. This approach provides a manipulable model system to interrogate the mechanism of the Ca2+ wave and the downstream changes associated with it.This work was supported by the University of Cambridge, ISSF to T.T.W. [grant number 097814]
The Effects of Trunk Muscle Training on Physical Fitness and Sport-Specific Performance in Young and Adult Athletes: A Systematic Review and Meta-Analysis.
Background The role of trunk muscle training (TMT) for physical ftness (e.g., muscle power) and sport-specifc performance measures (e.g., swimming time) in athletic populations has been extensively examined over the last decades. However, a
recent systematic review and meta-analysis on the efects of TMT on measures of physical ftness and sport-specifc performance in young and adult athletes is lacking.
Objective To aggregate the efects of TMT on measures of physical ftness and sport-specifc performance in young and adult athletes and identify potential subject-related moderator variables (e.g., age, sex, expertise level) and training-related programming parameters (e.g., frequency, study length, session duration, and number of training sessions) for TMT efects.
Data Sources A systematic literature search was conducted with PubMed, Web of Science, and SPORTDiscus, with no date restrictions, up to June 2021.
Study Eligibility Criteria Only controlled trials with baseline and follow-up measures were included if they examined the efects of TMT on at least one measure of physical ftness (e.g., maximal muscle strength, change-of-direction speed (CODS)/
agility, linear sprint speed) and sport-specifc performance (e.g., throwing velocity, swimming time) in young or adult competitive athletes at a regional, national, or international level. The expertise level was classifed as either elite (competing at
national and/or international level) or regional (i.e., recreational and sub-elite).
Study Appraisal and Synthesis Methods The methodological quality of TMT studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. A random-efects model was used to calculate weighted standardized mean diferences (SMDs) between intervention and active control groups. Additionally, univariate sub-group analyses were independently computed for subject-related moderator variables and training-related programming parameters.
Results Overall, 31 studies with 693 participants aged 11–37 years were eligible for inclusion. The methodological quality of the included studies was 5 on the PEDro scale. In terms of physical ftness, there were signifcant, small-to-large efects of TMT on maximal muscle strength (SMD =0.39), local muscular endurance (SMD =1.29), lower limb muscle power (SMD=0.30), linear sprint speed (SMD =0.66), and CODS/agility (SMD =0.70). Furthermore, a signifcant and moderate TMT efect was found for sport-specifc performance (SMD=0.64). Univariate sub-group analyses for subject-related moderator variables revealed signifcant efects of age on CODS/agility (p=0.04), with signifcantly large efects for children (SMD=1.53, p=0.002). Further, there was a signifcant efect of number of training sessions on muscle power and linear sprint speed (p≤0.03), with signifcant, small-to-large efects of TMT for>18 sessions compared to≤18 sessions (0.45≤SMD≤0.84, p≤0.003). Additionally, session duration signifcantly modulated TMT efects on linear sprint speed, CODS/agility, and sport-specifc performance (p≤0.05). TMT with session durations≤30 min resulted in signifcant, large efects on linear sprint speed and CODS/agility (1.66≤SMD≤2.42, p≤0.002), whereas session durations>30 min resulted in signifcant, large efects on sport-specifc performance (SMD=1.22, p=0.008).
Conclusions Our fndings indicate that TMT is an efective means to improve selected measures of physical ftness and sportspecifc performance in young and adult athletes. Independent sub-group analyses suggest that TMT has the potential to improve CODS/agility, but only in children. Additionally, more (>18) and/or shorter duration (≤30 min) TMT sessions appear to be more efective for improving lower limb muscle power, linear sprint speed, and CODS/agility in young or adult competitive athletes.publishedVersio
Evaluation of the Inheritance of the Complex Vertebral Malformation Syndrome by Breeding Studies
To investigate the congenital complex vertebral malformation syndrome (CVM) in Holstein calves, two breeding studies were performed including 262 and 363 cows, respectively. Cows were selected from the Danish Cattle Database based on pedigree and insemination records. Selected cows were progeny of sires with an established heterozygous CVM genotype and pregnant after insemination with semen from another sire with heterozygous CVM genotype. Following calving the breeders should state, if the calf was normal and was requested to submit dead calves for necropsy. In both studies, significantly fewer CVM affected calves than expected were obtained; a finding probably reflecting extensive intrauterine mortality in CVM affected foetuses. The findings illustrate increased intrauterine mortality as a major potential bias in observational studies of inherited disorders
Parental Leave policies, gender equity and family well being in Europe: a comparative perspective
Leave policies and the protection of working parents' rights have changed significantly
in Europe during the last few decades. While policies introduced immediately
after World War II were largely based on a male-breadwinner model, the post-1970s
policies have recognised the increase in maternal employment, the growing diversity
of work/family arrangements and working parents' needs for state support in caring
for young children. Paid maternity leave and paid or unpaid parental leave are
now available throughout Europe - Western, Central and Eastern - and policy developments
have encouraged more gender-neutral leaves and longer periods of paid
leave (Deven and Moss 2005)
Intakes of culinary herbs and spices from a food frequency questionnaire evaluated against 28-days estimated records
<p>Abstract</p> <p>Background</p> <p>Worldwide, herbs and spices are much used food flavourings. However, little data exist regarding actual dietary intake of culinary herbs and spices. We developed a food frequency questionnaire (FFQ) for the assessment of habitual diet the preceding year, with focus on phytochemical rich food, including herbs and spices. The aim of the present study was to evaluate the intakes of herbs and spices from the FFQ with estimates of intake from another dietary assessment method. Thus we compared the intake estimates from the FFQ with 28 days of estimated records of herb and spice consumption as a reference method.</p> <p>Methods</p> <p>The evaluation study was conducted among 146 free living adults, who filled in the FFQ and 2-4 weeks later carried out 28 days recording of herb and spice consumption. The FFQ included a section with questions about 27 individual culinary herbs and spices, while the records were open ended records for recording of herbs and spice consumption exclusively.</p> <p>Results</p> <p>Our study showed that the FFQ obtained slightly higher estimates of total intake of herbs and spices than the total intake assessed by the Herbs and Spice Records (HSR). The correlation between the two assessment methods with regard to total intake was good (r = 0.5), and the cross-classification suggests that the FFQ may be used to classify subjects according to total herb and spice intake. For the 8 most frequently consumed individual herbs and spices, the FFQ obtained good estimates of median frequency of intake for 2 herbs/spices, while good estimates of portion sizes were obtained for 4 out of 8 herbs/spices.</p> <p>Conclusions</p> <p>Our results suggested that the FFQ was able to give good estimates of frequency of intake and portion sizes on group level for several of the most frequently used herbs and spices. The FFQ was only able to fairly rank subjects according to frequency of intake of the 8 most frequently consumed herbs and spices. Other studies are warranted to further explore the intakes of culinary spices and herbs.</p
- …