A Pilot Study Comparing Muscle Activation and Kinematic Parameters Between Professional and Non-Professional Tennis Players

Tennis, a widely played sport across various age and skill groups, prompts continual skill improvement among competitive players seeking a competitive edge. This study explores two approaches for enhancing playing style: motion capture (MoCap) and surface electromyographic (sEMG) signals. The study addresses a gap in simultaneous examination of MoCap and entire dominant leg muscle activation, particularly concerning the influence of skill level and gender on various tennis strokes. To fill this void, the research records and analyzes MoCap and dominant leg sEMG data during serves and strokes on both court sides. The hypothesis posits differences in muscle activation and body mechanics between professional and non-professional players, as well as between male and female players. Recording employed XSENS MVN MoCap and an EMG system with WinDaq Pro Data Acquisition software. MoCap and sEMG data were recorded at rates of 60 Hz and 1200 Hz, respectively, focusing on seven target muscles on the dominant side. Gel-type electrodes were strategically placed on the skin for sEMG data collection and full body XSENS sensors were placed according to guidelines. Following comprehensive warm-up, baseline readings and various tennis strokes were recorded on both court sides. Data processing and analysis were conducted in MATLAB, encompassing filtering, rectification, interpolation, and visualization. The study\u27s findings contribute valuable insights into the relationship between motion and muscle activity in tennis, shedding light on skill-level and gender-related distinctions in player performance

All-Optical Nonzero-Field Vector Magnetic Sensor For Magnetoencephalography

We present the concept and the results of an investigation of an all-optical vector magnetic field sensor scheme developed for biological applications such as non-zero field magnetoencephalography and magnetocardiography. The scheme differs from the classical two-beam Bell-Bloom scheme in that the detecting laser beam is split into two beams, which are introduced into the cell in orthogonal directions, and the ratio of the amplitudes of the magnetic resonance signals in these beams and their phase difference are measured; strong optical pumping from the lower hyperfine level of the ground state ensures the resonance line narrowing, and detection in two beams is carried out in a balanced schemes by measuring the beam polarization rotation. The proposed sensor is compact, resistant to variations of parameters of laser radiation and highly sensitive to the angle of deflection of the magnetic field vector - with an estimated scalar sensitivity of the order of 16 fT/Hz1/2 in 8x8x8 mm3 cell, an angular sensitivity of 4x10-7 rad, or 0.08'', was demonstrated

Hydrogen-Bonded Complexes of Neutral Nitroxide Radicals with 2-Propanol Studied by Multifrequency EPR/ENDOR

The hydrogen bond plays a key role in weak directional intermolecular interactions. It is operative in determining molecular conformation and aggregation, and controls the function of many chemical systems, ranging from inorganic, organic to biological molecules. Although an enormous amount of spectroscopic information has been collected about hydrogen-bond formation between molecules with closed-shell electronic configuration, the details of such interactions between open-shell radicals and closed-shell molecules are still rare. Here we report on an investigation of hydrogen-bonded complexes between pyrroline-type as well as piperidine-type neutral nitroxide radicals and an alcohol, i.e., 2-propanol. These nitroxide radicals are commonly used as EPR spin labels and probes. To obtain information on the geometry of the complexes and their electronic structure, multi-resonance EPR techniques at various microwave frequencies (X-, Q-, W-band, 244 GHz) have been employed in conjunction with DFT calculations. The planar five-membered ring system of the pyrroline-type nitroxide radical was found to form exclusively well-defined in-plane σ-type hydrogen-bonded complexes with one 2-propanol molecule in the first solvation shell in frozen solution. The measured hyperfine parameters of the hydrogen-bridge proton and the internal magnetic parameters describing the electron Zeeman and the electron-nuclear hyperfine and nuclear quadrupole interactions are in good agreement with values predicted by state-of-the-art DFT calculations. In contrast, multi-resonance EPR on the non-planar six-membered ring system of the piperidine-type nitroxide radical (TEMPOL) reveals a more complex situation, i.e., a mixture of a σ-type with, presumably, an out-of-plane π-type complex, both present in comparable fraction in frozen solution. For TEMPOL, the DFT calculations failed to predict magnetic interaction parameters that are in good agreement with experiment, apparently due to the considerable flexibility of the nitroxide and hydrogen-bonded complex. The detailed information about nitroxide/solvent complexes is of particular importance for Dynamic Nuclear Polarization (DNP) and site-directed spin-labeling EPR studies that employ nitroxides as polarizing agents or spin labels, respectively

METROLOGICAL TRACEABILITY OF MOISTURE CONTENT MEASUREMENTS IN PLANT-ORIGIN BULK MATERIALS

This document explains advantages and disadvantages of the measurement methods for the moisture content determination of plant-based materials in order to identify the best one which can provide metrological traceability to SI units. The term “moisture” is generic and, to have proper Calibration and Measurement Capabilities (CMCs) and Certified Reference Materials (CRMs), a better specification of the measurand should be given. Currently, no CMCs for moisture content measurement in the plant-origin bulk materials, as well as respective CRMs, are available in the KCDB. Undoubtedly, those CMCs and CRMs are crucially needed to provide metrological traceability in this area

Hydrogen-bonded complexes of neutral nitroxide radicals with 2-propanol studied by multifrequency EPR/ENDOR

The hydrogen bond plays a key role in weak directional intermolecular interactions. It is operative in determining molecular conformation and aggregation, and controls the function of many chemical systems, ranging from inorganic, organic to biological molecules. Although an enormous amount of spectroscopic information has been collected about hydrogen-bond formation between molecules with closed-shell electronic configuration, the details of such interactions between open-shell radicals and closed-shell molecules are still rare. Here we report on an investigation of hydrogen-bonded complexes between pyrroline-type as well as piperidine-type neutral nitroxide radicals and an alcohol, i.e., 2-propanol. These nitroxide radicals are commonly used as EPR spin labels and probes. To obtain information on the geometry of the complexes and their electronic structure, multi-resonance EPR techniques at various microwave frequencies (X-, Q-, W-band, 244 GHz) have been employed in conjunction with DFT calculations. The planar five-membered ring system of the pyrroline-type nitroxide radical was found to form exclusively well-defined in-plane σ-type hydrogen-bonded complexes with one 2-propanol molecule in the first solvation shell in frozen solution. The measured hyperfine parameters of the hydrogen-bridge proton and the internal magnetic parameters describing the electron Zeeman and the electron-nuclear hyperfine and nuclear quadrupole interactions are in good agreement with values predicted by state-of-the-art DFT calculations. In contrast, multi-resonance EPR on the non-planar six-membered ring system of the piperidine-type nitroxide radical (TEMPOL) reveals a more complex situation, i.e., a mixture of a σ-type with, presumably, an out-of-plane π-type complex, both present in comparable fraction in frozen solution. For TEMPOL, the DFT calculations failed to predict magnetic interaction parameters that are in good agreement with experiment, apparently due to the considerable flexibility of the nitroxide and hydrogen-bonded complex. The detailed information about nitroxide/solvent complexes is of particular importance for Dynamic Nuclear Polarization (DNP) and site-directed spin-labeling EPR studies that employ nitroxides as polarizing agents or spin labels, respectively

Age-related differences in fixation gaze length while reading the news with negative text elements

The worldwide COVID-19 pandemic has led to the development of stress disorders and increased societal anxiety. The mass media is one of the most decisive factors leading to anxiety and stress in society during a pandemic. However, the mechanisms of mass media's stressogenic effects remain unclear. This study aimed to evaluate age-specific characteristics of gaze behavior related to the perception of anxiety-provoking information.  One hundred eighty-nine volunteers took part in the study – 164 participants aged between 17 and 22 years old (students, control group), 25 people aged between 59 and 71 (experimental group). We surveyed participants to determine their level of stress, depression, and anxiety and analyzed eye-tracking data during text perception by using the web eye-tracking technology EyePass. Results showed significant age-related differences in gaze behavior while reading texts with negative elements. Aged adults had shorter median fixation duration. There was no difference between groups in the number of fixations. We can assume that except age factor, other variables might have contributed to our result, namely the occupation of participants, professors at the Scientific and Educational Institute of Journalism, with developed professional skills (reading pattern, method of information perception) but from another side higher vulnerability to adverse COVID-19 outcomes compared to younger adults. Acknowledgements The authors of this article express their sincere gratitude to the National Research Foundation of Ukraine, thanks to whose financial and organizational support (grant “Stressogenic Elements of the Latent Impact of Real Media Reports on the COVID-19 Pandemic on Social Groups” No. 2020.01/0050), it became possible to conduct this study and publish the experimental results. Words of gratitude to the management and Scientific Council of the Foundation, curators of the project. Vast gratitude to the experts for their high evaluation of our project, thanks to whom our application won the competition. We want to express particular thanks to the management and our colleagues fromTaras Shevchenko National University of Kyiv, whose care and assistance contributed to the effective work within the project. Words of gratitude to colleagues and students who agreed to participate and actually contributed to the timely collection and processing of the experimental data. Disclosure Statement No potential conflict of interest was reported by the authors. Data Availability Statement The data that support the findings of this study are openly available in Mendeley Data https://doi.org/10.17632/rpytj9dkmx.3 * Corresponding author: Yurii Havrylets, 0000-0002-4899-5815 [email protected]

Making up Real Media Reports’ Sample on COVID-19 for Use in Experimental Studies

The article reveals the procedure of selecting real media reports (RMR) on the COVID-19 pandemic in experimental studies. We assumed that RMR during the pandemic and several lockdowns had a real impact on people from different social groups. To monitor messages about COVID-19, we used the online service "Software product LOOQME" The algorithm to form the RMR sample was as follows: (a) search for all media messages available on the platform, (b) analysis of selected RMR by online service, (c) forming of an experimental content sample and its embedding in the experiment. The method of selecting RMR considered in this article includes a theoretical rationale for RMR; broad thematic selection of RMR using media monitoring systems; forming an experimental content sample with the use of parameters and selection criteria; additional procedure for rating the selected RMR according to a particular criterion with the participation of experts

Does infant negative affect moderate the impact of parenting on effortful control? : a test of the differential susceptibility hypothesis

Committee members: Pittman, Laura D.; Shelleby, Elizabeth C.Advisor: Bridgett, David J.Includes illustrations.Includes bibliographical references.Parenting and early temperament characteristics have previously been shown to impact development of children's self-regulation, which is in turn linked to a variety of developmental outcomes. However, few studies have evaluated interactions between difficult temperament and parenting, and only four published studies have specifically tested whether infants' difficult temperament serves as a maker of differential susceptibility to parenting on self-regulatory development. The current study evaluated whether infant negative affectivity (NA) serves as a marker of differential susceptibility to positive and negative parenting on levels of effortful control (EC) at 18 months, which is at an earlier time point than has previously been tested. Using a sample of 179 mother-infant dyads, infant NA and parenting were evaluated when infants were 10 and 12 months, and EC was evaluated at 18 months using parent-report and observational measures. Results indicate that neither parenting nor infant NA have a significant direct impact on EC at 18 months, although a trend-level relationship between positive parenting and EC suggests that such relationships are emerging. None of the interactions between parenting and NA were found to support the differential susceptibility model, although a significant interaction between infant NA and intrusive, insensitive, and inconsistent parenting was found. However, this interaction suggests that infants low in NA benefit when exposed to intrusive, insensitive, and inconsistent parenting behaviors, which is inconsistent with the extant literature. Significant relationships were observed between covariates and EC such that having higher cumulative risk and being male were both negatively related to EC. It is likely that the lack of support for this study's hypotheses is due to the early time point at which EC was measured in this study, and that these factors have not yet had sufficient time to impact the neural structures underlying EC. Limitations and future directions are discussed.M.A. (Master of Arts

Towards a Practical Implementation of a Single-Beam All-Optical Non-Zero-Field Magnetic Sensor for Magnetoencephalographic Complexes

We present a single-beam all-optical two-channel magnetic sensor scheme developed for biological applications such as non-zero-field magnetoencephalography and magnetocardiography. The pumping, excitation and detection of magnetic resonance in two cells are performed using a single laser beam with time-modulated linear polarization: the linear polarization of the beam switches to orthogonal every half-cycle of the Larmor frequency. Light with such characteristics can be transmitted over a single-mode polarization-maintaining fiber without any loss in the quality of the polarization characteristics. We also present an algorithm for calculating optical elements in a sensor scheme, the results of measuring the parametric dependences of magnetic resonance in cells, and the results of direct testing of a sensor in a magnetic shield. We demonstrate sensitivity at the level of 20 fT/√Hz in one sensor channel in the frequency range of 80–200 Hz

Investigation of the Effect of Pulsed Power During Electrochemical Surface Modification of Aluminum and Titanium Alloy

PURPOSE: Aluminum and especially titanium alloy have become the focus of many studies due to their high strength to weight ratio and biocompatibility. Surgical implants need to have a hydrophilic nature when tissue growth is desired, while they need to be hydrophobic if tissue/microbial growth is not expected. Thus, there is a need to control the wettability of these metals. SUBJECTS: This study used a sodium chlorate electrolyte to control the wettability of 1 inch by 3 inch aluminum and titanium alloy samples using an electrochemical surface modification (ECSM) process. METHODS AND MATERIALS: Duty cycle, frequency, and ECSM duration were modified while voltage was held constant at 10 V. Duty cycles of 25%, 50%, 75%, and 100% (or DC) and frequencies of 1 kHz and 100 kHz were used. Time was changed to allow the samples to have an equal active time with 2000, 1000, 667, and 500 seconds for 25%, 50%, 75%, and 100% duty cycles, respectively. ANALYSES: A first principles based theoretical model was developed in this study to predict the pulse power setting needed to achieve the desired wettability in the samples by measuring the sample mass before and after ECSM. The model was validated with experimental results. RESULTS: The surface\u27s wettability switched from hydrophilic to hydrophobic after the sample was heated in a furnace. Both the metals showed a change in contact angle behavior after evaporation of the residual water. CONCLUSIONS: This study allows for the use of ECSM as a technique to modify the surface of implants with controlled wettability for improved osseointegration