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Problem: Since segment lengths of the lower extremities influence joint kinematics in multi-joint movements, anthropometric standardization seems necessary to study the force-length-velocity relationships of muscles in vivo. Mathematical approaches to calculate the needed linear velocities for the desired angular kinematics from individual anthropometric data exist and are in use. Nevertheless, this approach does not account for possible shifts due to cushion padding and soft tissue compression.Methods: 38 physical education students (31 male, 7 female, 244.32 years, 175.937.92 cm, 74.9310.86 kg) participated in this investigation. Knee-angles and angle-specific force during multi-joint isokinetic leg extensions derived from an anthropometric model were compared to corresponding knee angles and forces derived from optical marker tracking for two different linear velocities (0.1 m/s and 0.7 m/s).Results: The results show significant differences (p < 0.05) in knee angles and angle-specific forces for multi-joint isokinetic leg extensions with 0.1 m/s and no significant differences for movements with 0.7 m/s.Discussion: Studies investigating force-length-velocity relationships during multi-joint leg extensions should implement optical measurement to eliminate the effects of shifts due to cushion padding and soft tissue compression especially when working with slow linear velocities. The possibility of a device-specific correction for the anthropometric model should be addressed in further research.Key Words: Strength Testing, Force-Length Relationship, Force-Velocity Relationship

Problem: Sprinting represents a relevant task in many sports. The correlation of sprinting performance and squatting strength (1RM) has been shown in several investigations. Correlations with maximum strength in a linear isokinetic leg press are still pending. Since different devices produce different relationships and rotational isokinetic measurements show conflicting results, further evidence is needed.Methods: 23 male German junior elite volleyball players (16.721.07 years, 193.00.07 cm, 79.867.46 kg) were investigated. They performed sprints up to 30 meters and isokinetic leg press testing at 2 different velocities (0.1 m/s and 0.7 m/s). In the sprint the following times were recorded: 0-5m, 0-10m, 0-20m, 0-30m, 10-20m, 20-30m.Results: The strength tests revealed mean values of 4389.83 514.95 N (0.1 m/s) and 2690.83370.97 N (0.7 m/s), while the sprint test showed a mean performance of 4.340.17 s (30 m). Correlational analysis showed significant correlations (p

BackgroundFour large community-randomized trials examining universal testing and treatment (UTT) to reduce HIV transmission were conducted between 2012-2018 in Botswana, Kenya, Uganda, Zambia and South Africa. In 2014, the UNAIDS 90-90-90 targets were adopted as a useful metric to monitor coverage. We systematically review the approaches used by the trials to measure intervention delivery, and estimate coverage against the 90-90-90 targets. We aim to provide in-depth understanding of the background contexts and complexities that affect estimation of population-level coverage related to the 90-90-90 targets.MethodsEstimates were based predominantly on "process" data obtained during delivery of the interventions which included a combination of home-based and community-based services. Cascade coverage data included routine electronic health records, self-reported data, survey data, and active ascertainment of HIV viral load measurements in the field.ResultsThe estimated total adult populations of trial intervention communities included in this study ranged from 4,290 (TasP) to 142,250 (Zambian PopART Arm-B). The estimated total numbers of PLHIV ranged from 1,283 (TasP) to 20,541 (Zambian PopART Arm-B). By the end of intervention delivery, the first-90 target (knowledge of HIV status among all PLHIV) was met by all the trials (89.2%-94.0%). Three of the four trials also achieved the second- and third-90 targets, and viral suppression in BCPP and SEARCH exceeded the UNAIDS target of 73%, while viral suppression in the Zambian PopART Arm-A and B communities was within a small margin (~ 3%) of the target.ConclusionsAll four UTT trials aimed to implement wide-scale testing and treatment for HIV prevention at population level and showed substantial increases in testing and treatment for HIV in the intervention communities. This study has not uncovered any one estimation approach which is superior, rather that several approaches are available and researchers or policy makers seeking to measure coverage should reflect on background contexts and complexities that affect estimation of population-level coverage in their specific settings. All four trials surpassed UNAIDS targets for universal testing in their intervention communities ahead of the 2020 milestone. All but one of the trials also achieved the 90-90 targets for treatment and viral suppression. UTT is a realistic option to achieve 95-95-95 by 2030 and fast-track the end of the HIV epidemic.

Background Screening options for pancreatic ductal adenocarcinoma (PDAC) are limited. New-onset type 2 diabetes (NoD) is associated with subsequent diagnosis of PDAC in observational studies and may afford an opportunity for PDAC screening. We evaluated this association using a large administrative database. Methods Patients were identified using claims data from the OptumLabs® Data Warehouse. Adult patients with NoD diagnosis were matched 1:3 with patients without NoD using age, sex and chronic obstructive pulmonary disease (COPD) status. The event of PDAC diagnosis was compared between cohorts using the Kaplan–Meier method. Factors associated with PDAC diagnosis were evaluated with Cox's proportional hazards modeling. Results We identified 640 421 patients with NoD and included 1 921 263 controls. At 3 years, significantly more PDAC events were identified in the NoD group vs control group (579 vs 505; P  < 0.001). When controlling for patient factors, NoD was significantly associated with elevated risk of PDAC (HR 3.474, 95% CI 3.082–3.920, P  < 0.001). Other factors significantly associated with PDAC diagnosis were increasing age, increasing age among Black patients, and COPD diagnosis (P  ≤ 0.05). Conclusions NoD was independently associated with subsequent diagnosis of PDAC within 3 years. Future studies should evaluate the feasibility and benefit of PDAC screening in patients with NoD. [ABSTRACT FROM AUTHOR]

Surface phonon polaritons (SPhPs) are important building blocks of nanophotonics, as they enable strong light–matter interaction on the nanoscale, are well-suited for applications in the mid- to far-infrared regime, and can show low losses. SrTiO3 is an interesting material for SPhPs, because it allows for reversible, nonvolatile doping with free charge carriers via oxygen vacancies and for local switching with conductive AFM tips. As a result, SrTiO3 could enable programmable nanophotonics with tunable SPhPs and direct writing of metasurfaces. Surface polariton properties can be determined by mapping their real-space propagation using scattering-type scanning near-field optical microscopy (s-SNOM), which is sensitive to the high local electric fields with nanoscale lateral resolution. Low-confinement (LC) SPhPs with wavevectors close to that of free-space radiation, such as in SrTiO3 and the model polar dielectric SiC, can be difficult to investigate in s-SNOM due to interference effects with the incident illumination and fringe spacings exceeding the scan range or the size of the focus spot. Here, we present s-SNOM measurements of LC-SPhPs on SiC and SrTiO3 launched at gold stripes, retrieve physical quantities such as launching amplitude and phase, and show that they are influenced strongly by gold stripe geometry as well as illumination angle. Using two complementary measurements, we show a convenient way to determine the out-of-plane angle of the s-SNOM setup. Finally, we predict how control over the free charge carrier concentration in SrTiO3 could enable tunable LC-SPhPs, showing the potential of SrTiO3 for programmable nanophotonics. [ABSTRACT FROM AUTHOR]