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To evaluate the concurrent validity and test–retest reliability of common movement, strength, and balance tests using portable uniaxial dual force plates. Repeated measures cross-sectional study. Sixteen healthy individuals participated in two testing sessions, where they performed 12 different movement, strength, and balance tests. Vertical ground reaction force and centre of pressure data were collected using the VALD ForceDecks simultaneously with ground-embedded laboratory force plates. Concurrent validity was assessed using root mean square error for raw time-series data and Bland–Altman plots for discrete metrics. Test–retest reliability was assessed using intraclass correlation coefficients and minimal detectable changes. ForceDecks recorded vertical ground reaction forces and center of pressure with high accuracy compared to laboratory force plates. The mean bias between systems was negligible (<2 N or 0.1 mm), with small limits of agreement (<5 N or 1 mm). Overall, 530/674 (79%) showed good or excellent validity (<10% difference) and 611/773 (79%) had good or excellent reliability (intraclass correlation coefficient >0.75). ForceDecks reliability was similar to laboratory force plates (<0.07 intraclass correlation coefficient median difference for all metrics). Portable uniaxial force plates record highly accurate vertical ground reaction forces and center of pressure during a range of movement, strength, and balance tests. The VALD ForcDecks are a valid and reliable alternative to laboratory force plates when strict standardized testing and data analysis procedures are followed. Users should be aware of the validity and reliability characteristics of the tests and metrics they choose. [ABSTRACT FROM AUTHOR]

Objective: Our objective was to audit the provision and utilization of HIV post-exposure prophylaxis (PEP) to child rape survivors in the Province of KwaZulu-Natal, South Africa. Methods: A prospective design was used to collect data from a convenience sample of 200 consecutive cases of child rape referred for medico-legal assessment to a state hospital located to the north of the City of Durban (South Africa) in the period October to December 2004. For each case, information was obtained regarding demographic characteristics of the child, the child's HIV status at presentation, any excluding factors for PEP therapy, and the extent of adherence to the antiretroviral therapy regimen. Results: One hundred and twenty children (60%) qualified for PEP provision, with children being excluded because they refused initial HIV testing (1.5%), tested HIV positive at presentation (6.5%), or because of delayed (greater than 72 hour) presentation (32%). Of the 113 children who were followed through the PEP provision system, 40 (35.4%) returned for the full 28-day course, and only 4 (3.5%) returned at both 3- and 6-month follow up. Conclusions: Adherence rates for PEP therapy following child rape in South Africa are extremely low, with low adherence rates being associated with a theoretical risk of both reduced efficacy and drug resistance. In this context, there is a need for further research designed to identify the reasons for such non-adherence as well as a need for secondary prevention programs designed to both encourage more immediate reporting of child rape and to increase adherence to the PEP regimen.

A survey of 284 university men in South Africa found that a history of child sexual abuse involving physical contact was associated with elevated scores on all subscales of the Brief Symptom Inventory, whereas a history of noncontact forms of abuse produced no significant abuse-related effects. (Author/JDD)

• Using 3D digital models was not detrimental to the comprehension of students. • 3D digital models were positively received by students. • Students reported 3D models improved their confidence. • Students responded most positively to the use of 3D models when used in conjunction with 2D images. • 3D digital models are recommended as supplements to and not replacements of traditional bone labs. Forensic anthropology has traditionally relied on two-dimensional (2D) images, such as photographs and sketches, to perform analyses, and disseminate findings. However, as 3D imaging technology advances, it has become more widely implemented into forensic anthropology analysis and practice. Teaching and learning in forensic anthropology still often relies on 2D images, but increasingly three-dimensional (3D) models are available to be used by students training in anatomy and osteology. Additionally, 3D models have been found to be beneficial to comprehension in other contexts within forensic anthropology, such as in the courtroom. The use of these models in the teaching of forensic anthropology is not yet widely implemented and more importantly, the impact on learning is not yet understood. The use of 3D imaging and visualisation in other educational contexts has seen positive results, for example in medical training. To explore this further, a study was conducted using an online activity to compare the comprehension scores of students educated using 2D textbook style images or 3D models on Sketchfab. The results showed that the use of 3D images was not detrimental to comprehension. Students using the 3D models were more consistent in their performance and reported an increase in confidence regardless of prior experience. The results of this study are of particular importance when distance learning due to the COVID-19 pandemic which means that students cannot always learn in a laboratory environment. [ABSTRACT FROM AUTHOR]

To compare lower limb strength and countermovement jump (CMJ) kinetics between elite female footballers with and without a history of anterior cruciate ligament reconstruction (ACLR), hamstring strain, or hip/groin injury. Cross-sectional. Field-based. 369 elite female Australian football, soccer and rugby league players aged 15–35. Isometric hip adductor and abductor strength, eccentric knee flexor strength, and CMJ vertical ground reaction forces, including between-leg asymmetry. Players reported their lifetime history of ACLR, and whether they had sustained a hamstring strain, or hip/groin injury in the previous 12-months. Players with a unilateral history of ACLR (n = 24) had significant between-leg asymmetry in eccentric knee flexor strength (mean = −6.3%, 95%CI = −8.7 to −3.9%, P <.001), isometric hip abductor strength (mean = −2.5%, 95%CI = −4.3 to −0.7%, P =.008), and CMJ peak landing force (mean = −5.5%, 95%CI = −10.9 to −0.1%, P =.046). Together, between-leg asymmetry in eccentric knee flexor strength, isometric hip abductor strength, and CMJ peak landing force distinguished between players with and without prior ACLR with 93% accuracy. Elite female footballers with a history of ACLR, but not hamstring or hip/groin injury, exhibit persistent between-leg asymmetries in lower limb strength and jump kinetics following a return to sport. • Elite female footballers with prior ACLR display chronic between-leg asymmetries in knee flexor strength, hip abductor strength, and jump-landing force. • Lower limb strength and jump kinetics are not impaired after hamstring or hip/groin injury. • These data may have implications for ACLR rehabilitation and return to sport criteria. [ABSTRACT FROM AUTHOR]

Reports experiences during a two-year period in introducing the computer to the laboratory and students to the computer as a laboratory instrument. Describes a working philosophy, data acquisition system, and experiments. Summarizes the laboratory procedures of nine experiments, covering mechanics, heat, electromagnetism, and optics. (YP)

Objectives: This study examined whether young (15-19 years old) high-performance netball players exhibit different landing mechanics compared to female controls who do not participate in sports requiring frequent landings.Design: Comparative, cross-sectional.Methods: Lower limb kinematics and kinetics from 23 youth high performance female netball players (age: 17.5±1.7 years, height: 1.77±0.06m, mass: 66.5±6.33kg, netball experience: 8.5±2.3 years) were compared to data from 23 females (age: 22.0±3.2 years, height: 1.70±0.05m, mass: 64.4±6.7kg) who were involved in competitive sport, but had minimal experience playing a jump-landing sport. The jump landing task required participants to perform a countermovement jump and grab a netball suspended at 85% of the participant's maximum jump height. On random trials the ball was raised rapidly to 100% maximum jump height as the participant initiated her jump.Results: The netball group landed with significantly less contribution from the knee extensors to total work for the non-preferred leg (P<0.001, ds=1.10) than the inexperienced group. Although no other significant differences were found between groups, there were several small to moderate differences in several of the key biomechanical variables identified as being risk factors for ACL injury or associated with ACL strain.Conclusions: Both groups had similar knee valgus and internal rotation angles and moments, with nearly all participants presenting with relatively poor frontal plane knee control. Overall, results suggest that experience playing a netball may not be enough to develop low-risk landing mechanics. [ABSTRACT FROM AUTHOR]

Describes an undergraduate experiment which measures the energy gap in silicon and germanium. Theory, procedure, and results of this experiment are included. (HM)

Objectives: We investigated the impact of a standing desk intervention on daily objectively monitored sedentary behavior and physical activity in 6th grade school students.Design: Cluster non-randomised controlled trial.Method: Two classes (intervention students: n=22 [aged 11.8±0.4years]; control students: n=27 [11.6±0.5years]) from a public school in Lisbon were selected. The intervention involved replacing traditional seated classroom desks for standing desks, for a total duration of 16 weeks, in addition to performing teacher training and holding education/motivation sessions with students and parents. Sedentary behavior (ActivPAL inclinometer) and physical activity (Actigraph GT3X+ accelerometer) were measured for seven days immediately before and after the intervention.Results: There were no differences in baseline behaviors between intervention and control groups (p>0.05). At follow-up (16 weeks), it was observed that the intervention group had decreased time spent sitting (total week: -6.8% and at school: -13.0% relative to baseline) and increased standing (total week: 16.5% and at school: 31.0%) based on inclinometer values (p-value for interaction group*time <0.05). No significant differences in activity outcomes were observed outside school time (week or weekend) between groups.Conclusion: We conclude that a 16 week classroom standing desk intervention successfully reduced sitting time and increase standing time at school, with no observed compensatory effects outside of school time. [ABSTRACT FROM AUTHOR]

This study was aimed to investigate associations between birth weight and multiple adiposity indicators in youth, and to examine potential mediating effects by biological maturation. This was a school-based study involving 981 Brazilian adolescents aged between 10 and 17 years. Birth weight was reported retrospectively by mothers. Maturation was estimated by age of peak height velocity. Adiposity indicators included body mass index (BMI), waist circumference and percent body fat estimated from triceps and subscapular skinfolds. Multilevel mediation analyses were performed using the Sobel test, adjusted for chronological age, gestational age, cardiorespiratory fitness and socio-economic status. Except for body fat in girls, biological maturation partly or fully mediated (P<0.05) positive relationships between birth weight with all other obesity indicators in both sexes with their respective values of indirect effects with 95% confidence intervals: BMI [boys: 0.44 (0.06–0.82); girls: 0.38 (0.13–0.64)], waist circumference [boys: 1.14 (0.22–2.05); girls: 0.87 (0.26–1.48)] and body fat [boys: 0.60 (0.13–1.07)]. To conclude, birth weight is associated with elevated obesity risk in adolescence and biological maturation seems to at least partly mediate this relationship. [ABSTRACT FROM PUBLISHER]

Almost 30 years ago, when the study of chromonic liquid crystals was in its infancy, Alfred Saupe and L.J. Yu investigated disodium cromoglycate using deuteron magnetic resonance spectroscopy. Among their findings were that the quadrupolar splitting of the D2O spectrum increased with decreasing temperature and that the addition of salt to the solution increased the temperature stability of the nematic phase. A good deal of research on chromonic liquid crystals has been reported since that time, and therefore a lot more is known. However, it is also interesting that some of the questions from that time remain unanswered. [ABSTRACT FROM AUTHOR]