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Foot position during landing directly influences knee mechanics. Thus, the purpose of this study was to determine success in practicing, repeating, and transferring a desired foot progression angle (FPA) during landing, as well as changes in knee mechanics. Twenty females were randomly assigned to a control or verbal instruction group. On day 1, each group performed 40 drop landings. The verbal instruction group was instructed to "Land with 30 degrees of external rotation" before every trial. Feedback was provided on a terminal schedule in the form of knowledge of FPA error. On day 2, retention was assessed with 5 drop landings, while transfer was assessed during a 2-step stop-jump landing. Repeated-measures analyses of variance (2 × 4 [group × time]) were used to assess the influence of verbal instruction on knee mechanics. Participants who received verbal instruction exhibited increased FPA. They also demonstrated increased initial contact knee abduction during acquisition and retention. For all participants, initial contact knee flexion increased, while peak knee adduction moment decreased during acquisition. While the verbal instruction cue was effective in promoting an increase in FPA and reducing some ACL injury risk factors during practice and retention, this cue may only be effective to tasks similar to what was practiced. [ABSTRACT FROM AUTHOR]

Spectra of the weakly bound H2O–O2 dimer are studied in the region of the H2O ν2 band using a tunable quantum cascade laser to probe a pulsed supersonic slit jet expansion. These are the first gas-phase infrared spectra of H2O–O2 and among only a few such results for O2-containing complexes. Almost 100 infrared lines are assigned based on the ground state combination differences from the microwave spectrum of H2O–O2. These lines belong to a main fundamental band, plus four combination bands lying 2 to 5 cm−1 above the fundamental. All correspond to the ortho-H2O (I = 1) nuclear spin species. Interpretation of the observed rotational levels is discussed. The original microwave analysis conflicts with the infrared results but can be corrected by changing the sign of a term or, better still, by using a published theory for weakly bound open shell complexes. The combination bands suggest that analogous ground state bands should be observable in the millimeter wave range. Many infrared transitions remain unassigned, including another extensive band apparently centered at 1603 cm−1, and some of these are probably due to the para-H2O spin species (I = 0). Splittings due to the unpaired O2 electron spin (S = 1), due to large amplitude tunneling motions, and due to a-axis rotational motion all have similar magnitudes for H2O–O2, so the resulting energy levels will be heavily mixed and not amenable to simple modeling. Accurate theoretical predictions of these effects should be possible for obtaining an enhanced understanding of the observed spectra. [ABSTRACT FROM AUTHOR]

In biological systems such as cells, the macromolecules, which are anisotropic particles, diffuse in a crowded medium. In the present work, we have studied the diffusion of spheroidal particles diffusing between cylindrical obstacles by varying the density of the obstacles as well as the spheroidal particles. Analytical calculation of the free energy showed that the orientational vector of a single oblate particle will be aligned perpendicular, and a prolate particle will be aligned parallel to the symmetry axis of the cylindrical obstacles in equilibrium. The nematic transition of the system with and without obstacles remained the same, but in the case of obstacles, the nematic vector of the spheroid system always remained parallel to the cylindrical axis. The component of the translational diffusion coefficient of the spheroidal particle perpendicular to the axis of the cylinder is calculated for the isotropic system, which agrees with analytical calculation. When the cylinders overlap such that the spheroidal particles can only diffuse along the direction parallel to the axis of the cylinder, we can observe dimensional confinement. This was observed by the discontinuous fall of the diffusion coefficient, when plotted against the chemical potential both for a single particle and for a finite volume fraction. The rotational diffusion coefficient quickly reached the bulk value as the distance between the obstacles increased in the isotropic phase. In the nematic phase, the rotational motion of the spheroid should be arrested. We observed that even though the entire system remained in the nematic phase, the oblate particle close to the cylinder underwent a flipping motion. The consequence is that when the rotational mean squared displacement was calculated, it showed a super-diffusive behavior even though the orientational self-correlation function never relaxed to zero, showing this to be a very local effect. [ABSTRACT FROM AUTHOR]

Atomistically detailed force field is employed to investigate the dynamics of a naturally abundant deep eutectic solvent at 328 K, composed of glucose, urea, and water in a 6:4:1 mass ratio. This study examines key dynamical processes, including translational motion, molecular reorientation, and hydrogen bond relaxation, with timescales ranging from a few picoseconds to a few nanoseconds. Characteristic times associated with the translational and the rotational motion increase with molecular size, i.e., water being the fastest and glucose the slowest. Jump length analysis shows that urea and glucose traverse fractions of their molecular diameters during jumps, suggesting gliding motion. We find that water molecules exhibit strong anisotropic reorientation, which is moderate for urea and nearly absent in the case of glucose molecules. Correlation analysis of analogous transport quantities among the constituents reveals that reorientation of the dipole axis is less coupled to the translational diffusion compared to the reorientation around the dipolar axis. Finally, we observe that hydrogen bond relaxation times for water and urea are highly dependent on the number of hydrogen bonds formed, while for glucose, the slower molecular motion influences its hydrogen-bond relaxation. [ABSTRACT FROM AUTHOR]

The open-source Python package, MRSimulator, is presented as a simple-to-use, fast, versatile, and extendable package capable of simulating one- and higher-dimensional Nuclear Magnetic Resonance (NMR) spectra under static, magic-angle, and variable-angle conditions. High benchmarks in spectral simulations are achieved by assuming that there are no degeneracies in the energy eigenstates, i.e., all dipolar couplings are in the weak limit and that there are no rotational resonances during evolution periods. Under these assumptions, the symmetry pathway formalism is exploited to reduce an NMR method applied to a spin system into a sum of individual transition pathways, whose signals are more efficiently calculated individually than as part of a full-density matrix simulation. To increase numerical efficiencies further, our approach restricts coherence transfer among transitions to pure rotations about an axis in the x–y plane of the rotating frame or through an artificial total mixing operation between selected transitions of adjacent free evolution periods. The assumptions used in this approach are valid for most commonly used solid-state NMR methods. Details of the implementation, along with example code usage, are given, including a least-squares spectral analysis. [ABSTRACT FROM AUTHOR]

The quantum anomalous Hall effect (QAHE) enables dissipation-free motion within its edge states, offering considerable potential for developments in the fields of electronics, phononics, and elastic waves. In this study, we introduce an elastic metamaterial designed to realize the QAHE at low frequencies. Our approach involves deploying a two-dimensional honeycomb spring-mass system on a rotating platform to break time-reversal symmetry via the Coriolis Force and incorporating local resonators to achieve low-frequency topological edge states. We begin by deriving the system's equations of motion through analytical rigid body dynamics. Subsequently, we apply Bloch wave solutions to establish the dispersion relations and identify the topological edge states. We then conduct numerical simulations to confirm the one-way transmission characteristics of these states. The addition of local resonators not only extends the frequency range of the topological edge states but also lowers the operational frequency of the system. This robust waveguide, capable of one-way transmission, has potential applications in directional transmission, vibration damping, noise reduction, and acoustic imaging. [ABSTRACT FROM AUTHOR]

Rotational and vibrational energy relaxation (RER and VER) of N2O embedded in xenon and SF6 environments ranging from the gas phase to the liquid, including the supercritical regime, is studied at a molecular level. Calibrated intermolecular interactions from high-level electronic structure calculations, validated against experiments for the pure solvents, were used to carry out classical molecular dynamics simulations corresponding to experimental state points for near-critical isotherms. The computed RER rates in low-density solvents of k rot Xe = (3.67 ± 0.25) × 1 0 10 s−1 M−1 and k rot S F 6 = (1.25 ± 0.12) × 1 0 11 s−1 M−1 compare well with the rates determined by the analysis of two-dimensional infrared experiments. Simulations find that an isolated binary collision description is successful up to solvent concentrations of ∼ 4 M. For higher densities, including the supercritical regime, the simulations do not correctly describe RER, probably due to the neglect of solvent–solute coupling in the analysis of the rotational motion. For VER, the near-quantitative agreement between simulations and pump–probe experiments captures the solvent density-dependent trends. [ABSTRACT FROM AUTHOR]

Rotational and vibrational energy relaxation (RER and VER) of N2O embedded in xenon and SF6 environments ranging from the gas phase to the liquid, including the supercritical regime, is studied at a molecular level. Calibrated intermolecular interactions from high-level electronic structure calculations, validated against experiments for the pure solvents, were used to carry out classical molecular dynamics simulations corresponding to experimental state points for near-critical isotherms. The computed RER rates in low-density solvents of k rot Xe = (3.67 ± 0.25) × 1 0 10 s−1 M−1 and k rot S F 6 = (1.25 ± 0.12) × 1 0 11 s−1 M−1 compare well with the rates determined by the analysis of two-dimensional infrared experiments. Simulations find that an isolated binary collision description is successful up to solvent concentrations of ∼ 4 M. For higher densities, including the supercritical regime, the simulations do not correctly describe RER, probably due to the neglect of solvent–solute coupling in the analysis of the rotational motion. For VER, the near-quantitative agreement between simulations and pump–probe experiments captures the solvent density-dependent trends. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the rotational load fatigue performance of different implant diameters and abutment platforms of a one-size implant-abutment (OSIA) connection system. Materials and Methods: Narrow-, regular-, and wide-diameter implants were tested with regular base (RB/WB) abutments of an OSIA system (BLX, Straumann). Wide-diameter implants (WDIs) were also tested with wide base (WB) abutments. This resulted in four test groups: (1) narrow-diameter implants (NDIs; 3.5 mm) with RB/WB abutments, (2) regular-diameter implants (RDIs; 4.0 mm) with RB/WB abutments, (3) WDIs (5.0 mm) with RB/WB abutments, and (4) WDIs (5.0 mm) with WB abutments. Each group tested five of their respective implants (n = 5). A rotational load fatigue machine applied a sinusoidally varying stress at a 45-degree angle, producing an effective bending moment of 35 Ncm at a frequency of 10 Hz in 20°C air. The number of cycles to failure was recorded, and the results were evaluated using two-way ANOVA. Failed specimens were examined with a scanning electron microscope (SEM) to evaluate the failure mode. Pristine specimens were sectioned to examine the implant-abutment connection. Results: All specimens in three of the test groups with RB/WB abutments failed within the range of 558,750 cycles to 4,497,619 cycles, while the WDI-WB test group reached the upper limit of 5 million cycles without failure. A significant difference was found between abutment platforms (P < .001). There were no significant differences found for implant diameters (P = .857). However, with a greater implant diameter, implant fracture was less common, and the failure location was more coronal. It was consistently at the implant platform level for the abutment and at the screw neck. Conclusions: For WDIs, WB abutments exhibited superior fatigue performance compared to RB/WB abutments and would be preferred in situations of high mechanical risk. Increasing the implant diameter, when used with RB/WB abutments, did not improve fatigue performance due to the one-size prosthetic connection; however, failures were less catastrophic and coronally located, which may be advantageous in managing failures. [ABSTRACT FROM AUTHOR]

We employ classical density-functional theory to investigate the phase diagram of an assembly of mutually penetrable, parallel ellipsoids interacting via the generalized exponential model of index four (GEM-4) pair potential. We show that the crystal phases of the system are obtained from those of the spherically symmetric GEM-4 model by rescaling the lattice vectors. Performing this rescaling in combination with an arbitrary rotation of the lattice leads to infinitely many different structures with the same free energy, thereby implying their infinite degeneracy. These findings generalize to non-zero temperature the results formerly obtained by us [Pini et al., J. Chem. Phys. 153, 164901 (2020)] for the ground state of a similar system of ellipsoids interacting via a Gaussian potential. According to the mean-field free-energy functional used here, our conclusions apply to soft-core potentials both when they form cluster crystals as the GEM-4 and when they form single-occupancy crystals as the Gaussian itself. [ABSTRACT FROM AUTHOR]

Magnetic force microscopy (MFM) is long established as a powerful tool for probing the local stray fields of magnetic nanostructures across a range of temperatures and applied stimuli. A major drawback of the technique, however, is that the detection of stray fields emanating from a sample's surface rely on a uniaxial vertical cantilever oscillation, and thus are only sensitive to vertically oriented stray field components. The last two decades have shown an ever-increasing literature fascination for exotic topological windings where particular attention to in-plane magnetic moment rotation is highly valuable when identifying and understanding such systems. Here, we present a method of detecting in-plane magnetic stray field components, by utilizing a split-electrode excitation piezo that allows the simultaneous excitation of a cantilever at its fundamental flexural and torsional modes. This allows for the joint acquisition of traditional vertical mode images and a lateral MFM where the tip–cantilever system is only sensitive to stray fields acting perpendicular to the torsional axis of the cantilever. [ABSTRACT FROM AUTHOR]

For floppy molecules showing internal rotations and/or large amplitude motions, curvilinear internal coordinates are known to be superior to rectilinear normal coordinates within vibrational structure calculations. Due to the myriad definitions of internal coordinates, automated and efficient potential energy surface generators necessitate a high degree of flexibility, supporting the properties arising from these coordinates. Within this work, an approach to deal with these challenges is presented, including key elements, such as the selection of appropriate fit functions, the exploitation of symmetry, the positioning of grid points, or elongation limits for different coordinates. These elements are tested for five definitions of curvilinear coordinates, with three of them being generated in an automated manner. Calculations for semi-rigid molecules, namely H2O, H2CO, CH2F2, and H2CNH, demonstrate the general functionality of the implemented algorithms. Additional calculations for the HOPO molecule highlight the benefits of these curvilinear coordinates for systems with large amplitude motions. This new implementation allowed us to compare the performance of these different coordinate systems with respect to the convergence of the underlying expansion of the potential energy surface and subsequent vibrational configuration interaction calculations. [ABSTRACT FROM AUTHOR]

Context: To stabilize the humeral head within the glenoid fossa during arm elevation, the rotator cuff muscles may contribute through internal and external rotation. The main purpose of the current study was to compare the acromiohumeral distance between athletes with primary subacromial impingement syndrome who received progressive resistance exercises consisting of either shoulder internal or external rotation. Design: A randomized and controlled clinical study. Methods: Thirty athletes with primary subacromial impingement syndrome were enrolled and randomly divided into 2 experimental groups. The progressive resistance exercise protocol in experimental group I comprised shoulder internal rotation, while in experimental group II consisted of shoulder external rotation. The experimental groups worked out 3 days a week for 6 weeks. The experimental groups were compared with the control group consisting of 15 healthy athletes. The acromiohumeral distance was measured before and after the intervention using an ultrasound machine under the passive and active across no arm elevation and 45°of arm elevation. Results: The acromiohumeral distance significantly increased in both experimental groups under the passive and active arm positions following the intervention (P <.001), with no significant differences detected between the experimental groups (P >.665). The paired comparisons of the acromiohumeral distance discrepancy indicated a significant difference between the control group and each experimental group under the active and passive arm positions (P <.001), while no significant difference was observed between the experimental groups (P >.999). Conclusions: The present study revealed, for the first time, that both progressive resistance exercise protocols involving either the shoulder internal or the external rotation increased the acromiohumeral distance in individuals with primary subacromial impingement syndrome and improved associated pain and disabilities. [ABSTRACT FROM AUTHOR]

Context: The best current evidence supports the effectiveness of neuromuscular training in reducing the risk of injury; however, the rate of anterior cruciate ligament (ACL) injuries is still high. Neurocognitive training (NT) has successfully improved biomechanical risk factors, but they have been considered in only a few studies. Objective: To review the literature to determine the effect of NT on biomechanical risk factors related to ACL injury in athletes. Evidence Acquisition: We searched PubMed, Google Scholar, Scopus, Science Direct, and the Physiotherapy Evidence Database from inception to August 2011. We included randomized controlled trials that used motor learning approaches and injury prevention programs to investigate kinematic and kinetic risk factors related to ACL injury. The quality of each clinical trial study was evaluated by the Physiotherapy Evidence Database scale. The eligibility criteria were checked based on the PICOS (population, intervention, comparison, outcome, and study type) framework. Evidence Synthesis: A total of 9 studies were included in the final analysis. Motor learning approaches include internal and external focus of attention, dual tasks, visual motor training, self-control feedback, differential learning, and linear and nonlinear pedagogy, combined with exercise programs. In most of the studies that used NT, a significant decrease in knee valgus; tibial abduction and external rotation; ground reaction force; and an increase in knee-, trunk-, hip-, and knee-flexion moment was observed. Conclusion: In classical NT, deviation from the ideal movement pattern especially emphasizing variability and self-discovery processes is functional in injury prevention and may mitigate biomechanical risk factors of ACL injuries in athletes. Practitioners are advised to use sport-specific cognitive tasks in combination with neuromuscular training to simulate loads of the competitive environment. This may improve ACL injury risk reduction and rehabilitation programs. [ABSTRACT FROM AUTHOR]

The generation of acoustic vortex beams has garnered significant research interest in recent years due to their diverse applications, including acoustic communication, particle manipulation, and biomedical ultrasound. However, incorporating more vortices and expanding the capacity of these beams and related devices in three dimensions remain challenging. In this study, we propose a phase-constrained iterative angular spectrum method for fabricating a 3D-printed holographic lens capable of reconstructing multi-vortex acoustic beams within a 3D volume. To evaluate the performance of the proposed lens, we conduct tests using both numerical simulations and practical underwater measurements. Furthermore, we demonstrate the transfer of acoustic angular momentum to two absorbent acoustic objects, achieving rotation of these objects with the performance influenced by vortices at target positions. The results indicate that the proposed method can generate multiple acoustic vortex beams within a 3D volume. This capability enhances the effectiveness and versatility of various applications, such as the manipulation of three-dimensional objects and high-density information transmission. [ABSTRACT FROM AUTHOR]

Molecular donor–acceptor (D–A) linked systems have attracted significant attention due to their potential to address D–A interactions in excited states. In these systems, it is crucial to understand the interplay between electrons and spin behaviors, atomic nucleus movements (including vibration, rotation, fluctuation, and transfer), and collective motion (electron–phonon coupling) over time. Through intentional manipulation of locally excited, charge-transfer excited, and charge-separated states, along with modulation of dynamic effects (enhancement or restraint), we expect to unlock the full potential of D–A systems for photofunctions in electronics, energy, healthcare, and functional materials. In this perspective, we present our recent examples of D–A linked systems and related ones that address the aforementioned issues as part of our "Dynamic Exciton" research project in Japan. [ABSTRACT FROM AUTHOR]

Molecular rotations influence numerous condensed matter phenomena but are often difficult to isolate in molecular dynamics (MD) simulations. This work presents a rotational/roto-translational constraint algorithm designed for condensed matter simulations. The method is based on the velocity Verlet scheme, ensuring a direct constraint on velocity and simplifying implementation within material simulation software packages. We implemented the algorithm in a customized version of a CP2K package and validated its effectiveness through MD simulations of molecule and crystal. The results demonstrate successful selective constraint of rotational and roto-translational motions, enabling stable long-term simulations. This capability opens avenues for studying rotation-related phenomena (e.g., paddle-wheel mechanism in solid-state electrolytes) and constrained sampling. [ABSTRACT FROM AUTHOR]

Purpose: This study assessed the reliability and load–velocity profiles of 3 different landmine-punch-throw variations (seated without trunk rotation, seated with trunk rotation, and standing whole body) with different loads (20, 22.5, and 25.0 kg), all with the dominant hand and nondominant hand. Methods: In a quasi-randomized order, 14 boxers (24.1 [4.3] y, 72.6 [10.1] kg) performed 3 repetitions of each variation with their dominant hand and their nondominant hand, with maximal effort and 3 minutes of interset rest. Peak velocity was measured via the GymAware Power Tool (Kinetic Performance Technologies). The interclass correlation coefficients and their 95% CIs were used to determine the intrasession reliability of each variation × load × hand combination. Additionally, a 2 (hand) × 3 (variation) repeated-measures analysis of variance assessed the load–velocity profile slope, and a 3 (variation) × 2 (hand) × 3 (load) repeated-measures analysis of variance assessed the peak velocity of each variation. Results: Most variations were highly reliable (intraclass correlation coefficient >.91), with the nondominant hand being as reliable or more reliable than the dominant hand. Very strong linear relationships were observed for the group average for each variation (R2 ≥.96). However, there was no variation × hand interaction for the slope, and there was no main effect for variation or hand. Additionally, there was no interaction for the peak velocity, but there were main effects for variation, hand, and load (P <.01). Conclusion: Each variation was reliable and can be used to create upper-body ballistic unilateral load–velocity profiles. However, as with other research on load–velocity profile, individual data allowed for more accurate profiling than group average data. [ABSTRACT FROM AUTHOR]

Applying an excess entropy scaling formalism to the coarse-grained (CG) dynamics of liquids, we discovered that missing rotational motions during the CG process are responsible for artificially accelerated CG dynamics. In the context of the dynamic representability between the fine-grained (FG) and CG dynamics, this work introduces the well-known Stokes–Einstein and Stokes–Einstein–Debye relations to unravel the rotational dynamics underlying FG trajectories, thereby allowing for an indirect evaluation of the effective rotations based only on the translational information at the reduced CG resolution. Since the representability issue in CG modeling limits a direct evaluation of the shear stress appearing in the Stokes–Einstein and Stokes–Einstein–Debye relations, we introduce a translational relaxation time as a proxy to employ these relations, and we demonstrate that these relations hold for the ambient conditions studied in our series of work. Additional theoretical links to our previous work are also established. First, we demonstrate that the effective hard sphere radius determined by the classical perturbation theory can approximate the complex hydrodynamic radius value reasonably well. Furthermore, we present a simple derivation of an excess entropy scaling relationship for viscosity by estimating the elliptical integral of molecules. In turn, since the translational and rotational motions at the FG level are correlated to each other, we conclude that the "entropy-free" CG diffusion only depends on the shape of the reference molecule. Our results and analyses impart an alternative way of recovering the FG diffusion from the CG description by coupling the translational and rotational motions at the hydrodynamic level. [ABSTRACT FROM AUTHOR]

Relief supply inventories are important in disaster response operations. To address the problem of dead stocks and avoid relief supply expiration, such inventories must be renewed periodically. Different from the traditional shelf-life rotation mechanism (i.e. renewal of the entire inventory at the expiration date), which pays more attention to decreasing the quantity of dead stocks, the novel period rotation mechanism that we design in this study will gradually rotate relief supplies according to their shelf life. We propose a mathematical programming model to minimise the total cost of relief organisations and conduct a case study and analyse the sensitivity of key parameters using real-world data. Results show that our rotation mechanism can substantially reduce the financial burden on relief organisations and improve the quality of relief supplies for victims. The novelty of our study includes: (1) We introduce a new approach that can rotate multiple times, through which we consider the quality of relief supplies; (2) We incorporate recycling and remanufacturing into the rotation process; and (3) We adopt an inductive reasoning method to develop the model with demand and time uncertainties. We prove the feasibility of our model and contributions of our study to humanitarian logistics practice and research. [ABSTRACT FROM AUTHOR]

The lifetime of a hydrogen bond between water and dimethyl sulfoxide (DMSO) is found to be considerably longer than that between two water molecules in neat water. This is counter-intuitive because the charge on the oxygen in DMSO is considerably less than that in water. Additionally, the strength of the water–dimethyl sulfoxide (w–D) hydrogen bond is found to be strongly composition dependent; the lifetime of the hydrogen bond is ten times larger at 30% than at very low concentrations. Using computer simulations, we perform microscopic structural and dynamic analysis to find that these anomalies arise at least partly from an "action-at-a-distance" effect where the attraction between the hydrophobic methyl groups results in the self-aggregation of DMSO molecules that "cages" both the rotational and linear motions of the molecules involved. This is reflected in the observed strong correlation of the lifetime with the local coordination number of the associated methyl groups. The elongated w–D h-bond lifetime causes a slowdown of collective dynamics and affects the lifetime of the w–w h-bond. This nonlinear feedback mechanism explains the strong composition dependence of viscosity and is anticipated to play a dominant role in many self-assemblies. Furthermore, the w–D hydrogen bond breaking mechanism changes from low to high DMSO concentration, a phenomenon not anticipated a priori. We introduce a new order parameter-based free energy surface of the bond breaking pathway. A two-dimensional transition state rate theory calculation is performed for the lifetime of the w–D h-bond that is found to be semi-quantitatively accurate. [ABSTRACT FROM AUTHOR]

In dense particle systems, the coupling of rotation and translation motion becomes intricate. Here, we report the results of confocal fluorescence microscopy where simultaneous recording of translational and rotational particle trajectories from a bidisperse colloidal dispersion is achieved by spiking the samples with rotational probe particles. The latter consist of colloidal particles containing two fluorescently labeled cores suited for tracking the particle's orientation. A comparison of the experimental data with event driven Brownian simulations gives insights into the system's structure and dynamics close to the glass transition and sheds new light onto the translation–rotation coupling. The data show that with increasing volume fractions, translational dynamics slows down drastically, whereas rotational dynamics changes very little. We find convincing agreement between simulation and experiments, even though the simulations neglect far-field hydrodynamic interactions. An additional analysis of the glass transition following mode coupling theory works well for the structural dynamics but indicates a decoupling of the diffusion of the smaller particle species. Shear stress correlations do not decorrelate in the simulated glass states and are not affected by rotational motion. [ABSTRACT FROM AUTHOR]

Context: Sport-specific adaptations in shoulder rotation range of motion (ROM) and the relationship with humeral torsion have been described in overhead-throwing sports. However, information is lacking for other shoulder-loading sports such as field hockey. Therefore, this study's purpose was to evaluate humeral torsion in elite, male field hockey players and explore its association with shoulder ROM. Design: Cross-sectional study. Methods: Twenty-five male, elite field hockey players were included. Humeral torsion and shoulder external and internal rotation ROM were evaluated bilaterally by ultrasound and an inclinometer smartphone application, respectively. Results: Field hockey players showed a significantly increased humeral retroversion on the dominant compared with the nondominant side (P <.001; Cohen d = 1.75), along with a significantly increased external (P =.004; Cohen d = −0.64) and decreased internal rotation ROM (P =.003; Cohen d = 0.65). This finding illustrates a shift in total shoulder rotational ROM arc. Correlation analysis showed a significant moderate association between the increased humeral retroversion and decreased internal rotation ROM on the dominant side (r =.523). Conclusions: Elite male field hockey athletes show sport-specific adaptations regarding humeral torsion and shoulder rotation ROM, similar to throwing athletes. These findings increase our insight into the field hockey athlete's shoulder, which is essential to optimize performance and assist in correctly interpreting shoulder rotational ROM measurements. [ABSTRACT FROM AUTHOR]

The rotational spectrum of an acrolein–formaldehyde complex has been characterized using pulsed jet Fourier transform microwave spectroscopy complemented with quantum chemical calculations. One isomer has been observed in pulsed jets, which is stabilized by a dominant O=C⋯O tetrel bond (n → π* interaction) and a secondary C–H⋯O hydrogen bond. Splittings arising from the internal rotation of formaldehyde around its C2v axis were also observed, from which its V2 barrier was evaluated. It seems that when V2 equals or exceeds 4.61 kJ mol−1, no splitting of the spectral lines of the rotational spectrum was observed. The nature of the non-covalent interactions of the target complex is elucidated through natural bond orbital analysis. These findings contribute to a deeper understanding on the non-covalent interactions within the dimeric complex formed by two aldehydes. [ABSTRACT FROM AUTHOR]

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Altering baseball pitching mechanics affects both performance and the risk of injury. The purpose of this study is to investigate the relationships of shoulder external over internal rotation ratio (SEIR) and other shoulder rotational properties during physical exam and biomechanics of pitching for 177 collegiate baseball pitchers. The shoulder range of motion was quantitatively measured using a custom-made wireless device. Pitching motion data were collected at 240 Hz, and a custom program was created to calculate the throwing arm motion and loading during baseball pitching. Linear regression and analysis of variance tests were performed to investigate the relationships between the shoulder physical exam outcomes and throwing arm biomechanics. SEIR had significant correlations with shoulder horizontal adduction angle at foot contact, maximum shoulder external rotation angle, maximum shoulder linear velocity, and elbow angle at ball release. SEIR groups had significant differences in shoulder proximal force, adduction torque, internal rotation torque, and horizontal adduction torque, and in elbow medial force and varus torque. Glenohumeral internal rotation deficit and total rotational motion deficit had no relationships with throwing arm motions or joint loadings. Shoulder health should be monitored to improve understanding of pitching mechanics in collegiate baseball pitchers. [ABSTRACT FROM AUTHOR]

Context: Piriformis syndrome is often associated with muscle spasms and shortening of the piriformis muscle (PM). Physical therapy, including static stretching of the PM, is one of the treatments for this syndrome. However, the effective stretching position ofthe PM is unclear in vivo. This study aimed to determine the effective stretching positions of the PM using ultrasonic shear wave elastography. Design: Observational study. Methods: Twenty-one healthy young men (22.7 [2.41 y) participated in this study. The shear elastic modulus of the PM was measured at 12 stretching positions using shear wave elastography. Three of the 12 positions were tested with maximum internal rotation at 0°, 20°, or 40° hip adduction in 90° hip flexion. Nine of the 12 positions were tested with maximum external rotation at positions combined with 3 hip-flexion angles (70°, 90°, and 110°) and 3 hip-adduction angles (0°, 20°, and 40°). Results.' The shear elastic modulus of the PM was significantly higher in the order of 40°, 20°, and 0° of adduction and higher in external rotation than in internal rotation. The shear elastic modulus of the PM was significantly greater in combined 110° hip flexion and 40° adduction with maximum external rotation than in all other positions. Conclusion.- This study revealed that the position in which the PM was most stretched was maximum external rotation with 110° hip ftexion and 40° hip adduction. [ABSTRACT FROM AUTHOR]

Molecular anisotropy plays an important role in the glass transition of a liquid. Recently, a novel bulk glass state has been discovered by optical microscopy experiments on suspensions of ellipsoidal colloids. "Liquid glass" is a disordered analog of a nematic liquid crystal, in which rotation motion is hindered but particles diffuse freely. Global nematic order is suppressed as clusters of aligned particles intertwine. We perform Brownian dynamics simulations to test the structure and dynamics of a dense system of soft ellipsoidal particles. As seen in the experiments and in accordance with predictions from the mode coupling theory, on the time scale of our simulations, rotation motion is frozen but translation motion persists in liquid glass. Analyses of the dynamic structure functions for translation and rotation corroborates the presence of two separate glass transitions for rotation and translation, respectively. Even though the equilibrium state should be nematic, aligned structures remain small and orientational order rapidly decays with increasing size. Long-wavelength fluctuations are remnants of the isotropic-nematic transition. [ABSTRACT FROM AUTHOR]

Microsolvation of the carbamate moiety delivers precise information on complexation effects on the N–C=O backbone and is of relevance to the peptide bond functionality. In this context, the mono-, di-, and trihydrated complexes of methyl carbamate have been studied in molecular expansion by high-resolution microwave spectroscopy, using chirped-pulse and Fabry–Perot resonator Fourier transform microwave instruments covering the frequency range from 2 to 18 GHz. From the rotational constants of the parent and the 18Ow substituted monoisotopologues, accurate values have been derived for the geometries of the hydrogen bond interactions. The nuclear quadrupole coupling constant χcc of the nitrogen nucleus provides a direct measure of complexation changes and decreases with the degree of hydration, whereas the hindered internal rotation barrier increases slightly with microsolvation. Both tendencies could have a common origin in the π-cooperative inductive effects as the microsolvation series progresses. All transitions are split by the internal rotation of the methyl top and the nuclear quadrupole coupling, and in the largest cluster, they are additionally split by an inversion motion. [ABSTRACT FROM AUTHOR]

We investigated the rotational spectrum of 2,5-dimethylfluorobenzene containing coupled large amplitude motions of two methyl groups in the frequency range from 2 to 26.5 GHz using a pulsed molecular jet Fourier transform microwave spectrometer. The internal rotation of two inequivalent methyl groups with low torsional barriers (around 16 and 226 cm−1) causes splittings of all rotational transitions into quintets with separations of up to hundreds of MHz between the torsional components. Spectral analysis and modeling of the observed splittings were performed using the programs XIAM and BELGI-Cs-2Tops, whereby the latter achieved measurement accuracy. The methyl internal rotation can be used to examine the electronic and steric environments around the methyl group because they affect the methyl torsional barrier. Electronic properties play a particularly important role in aromatic molecules in the presence of a π-conjugated double bond system. The experimental results were compared with those of quantum chemistry. Benchmark calculations resulted in the conclusion that the B3LYP-D3BJ/6-311++G(d,p) level of theory can be recommended for predicting rotational constants to guide the microwave spectral assignment of dimethylfluorobenzenes in particular and toluene derivatives in general. [ABSTRACT FROM AUTHOR]

Biased and accelerated molecular simulations (BAMS) are widely used tools to observe relevant molecular phenomena occurring on time scales inaccessible to standard molecular dynamics, but evaluation of the physical time scales involved in the processes is not directly possible from them. For this reason, the problem of recovering dynamics from such kinds of simulations is the object of very active research due to the relevant theoretical and practical implications of dynamics on the properties of both natural and synthetic molecular systems. In a recent paper [A. Rapallo et al., J. Comput. Chem. 42, 586–599 (2021)], it has been shown how the coupling of BAMS (which destroys the dynamics but allows to calculate average properties) with Extended Diffusion Theory (EDT) (which requires input appropriate equilibrium averages calculated over the BAMS trajectories) allows to effectively use the Smoluchowski equation to calculate the orientational time correlation function of the head–tail unit vector defined over a peptide in water solution. Orientational relaxation of this vector is the result of the coupling of internal molecular motions with overall molecular rotation, and it was very well described by correlation functions expressed in terms of weighted sums of suitable time-exponentially decaying functions, in agreement with a Brownian diffusive regime. However, situations occur where exponentially decaying functions are no longer appropriate to capture the actual dynamical behavior, which exhibits persistent long time correlations, compatible with the so called subdiffusive regimes. In this paper, a generalization of EDT will be given, exploiting a fractional Smoluchowski equation (FEDT) to capture the non-exponential character observed in the relaxation of intramolecular distances and molecular radius of gyration, whose dynamics depend on internal molecular motions only. The calculation methods, proper to EDT, are adapted to implement the generalization of the theory, and the resulting algorithm confirms FEDT as a tool of practical value in recovering dynamics from BAMS, to be used in general situations, involving both regular and anomalous diffusion regimes. [ABSTRACT FROM AUTHOR]

Two-level quantum systems are fundamental physical models that continue to attract growing interest due to their crucial role as a building block of quantum technologies. The exact analytical solution of the dynamics of these systems is central to control theory and its applications, such as that to quantum computing. In this study, we reconsider the two-state charge transfer problem by extending and using a methodology developed to study (pseudo)spin systems in quantum electrodynamics contexts. This approach allows us to build a time evolution operator for the charge transfer system and to show new opportunities for the coherent control of the system dynamics, with a particular emphasis on the critical dynamic region around the transition state coordinate, where the avoided crossing of the energy levels occurs. We identify and propose possible experimental implementations of a class of rotations of the charge donor (or acceptor) that endow the electronic coupling matrix element with a time-dependent phase that can be employed to realize controllable coherent dynamics of the system across the avoided level crossing. The analogy of these rotations to reference frame rotations in generalized semiclassical Rabi models is discussed. We also show that the physical rotations in the charge-transfer systems can be performed so as to implement quantum gates relevant to quantum computing. From an exquisitely physical–mathematical viewpoint, our approach brings to light situations in which the time-dependent state of the system can be obtained without resorting to the special functions appearing in the Landau–Zener approach. [ABSTRACT FROM AUTHOR]

Magnetic skyrmion bags are composite topological spin textures with arbitrary topological charges. Here, we computationally study the transient rotational motion of skyrmion bags, which is characterized by a global rotation of inner skyrmions around the central point. Distinct from conventional rotational modes found in skyrmions, the observed rotation is a forced motion associated with the breathing mode induced solely by vertical microwave fields. The driving force behind this rotation originates from the interactions between outer and inner skyrmions, with the angular velocity determined by the phase difference resulting from their asynchronous breathing behaviors. It is also found that skyrmion bags with larger skyrmion numbers are more conducive to the occurrence of the rotation. Our results are useful for understanding the cluster dynamics of complex topological spin textures driven by dynamic fields. [ABSTRACT FROM AUTHOR]

When polarized light is incident on a magnetic material, the magneto-optical Kerr effect (MOKE) rotates the polarization and induces ellipticity in the reflected light, which allows the magnetization direction to be probed optically. The Kerr rotation and ellipticity determine the magnitude of the effect and are usually measured using dedicated ellipsometers. Here, we demonstrate a simple method for extracting Kerr rotation and ellipticity in magnetic thin films using a conventional MOKE magnetometer consisting of two polarizers and a quarter waveplate. Using this technique, we report the longitudinal Kerr angle of BiYIG, GdCo, and TbCo. We additionally observe a linear decrease in polar complex Kerr angle magnitude in 3 nm GdCo films as the atomic fraction of Gd is increased. [ABSTRACT FROM AUTHOR]

Quantum state-to-state nonadiabatic dynamics of the charge transfer reaction H+ + NO(X2Π, vi = 1, 3, ji = 0, 1) → H + NO+(X1Σ+) has been studied based on the recently constructed diabatic potential energy matrix. It was found that the vibrational excitation of reactant NO inhibits the reactivity, while the rotational excitation of reactant NO has little effect on the reaction probability. These attributes were also observed in the semi-classical trajectory calculations employed in the adiabatic representation. Such an inhibitory effect of the vibrational excitation of reactant NO was owing to lower accessibility of the conical intersection and avoided crossing regions, which are located in the wells with respect to the Π diabat, as evidenced by the analysis of the population of the time-independent wave functions. Calculated vibrational state distributions of the product show that the decrease of the reaction mainly leads to the less formation of low vibrational states (vf < 6), and the product vibrational state distributions are more evenly populated for vi = 1 and 3, suggesting a non-statistical behavior. However, the overall shapes of the product rotational distributions remain unchanged, indicating that the redistribution of energy into the rotation of product NO is sufficient in the charge transfer process between H+ and NO. While the reaction is dominated by the forward and backward scattering in differential cross sections (DCSs), consistent with the complex-forming mechanism, a clear forward bias in the DCSs appears, indicating that the occurrence of the reaction is not sufficiently long to undergo the whole phase space of the interaction configurations. [ABSTRACT FROM AUTHOR]

Understanding water dynamics at charged interfaces is of great importance in various fields, such as catalysis, biomedical processes, and solar cell materials. In this study, we implemented molecular dynamics simulations of a system of pure water interfaced with Au electrodes, on one side of which 4-mercaptobenzonitrile (4-MBN) molecules are adsorbed. We calculated time correlation functions of various dynamic quantities, such as the hydrogen bond status of the N atom of the adsorbed 4-MBN molecules, the rotational motion of the water OH bond, hydrogen bonds between 4-MBN and water, and hydrogen bonds between water molecules in the interface region. Using the Luzar–Chandler model, we analyzed the hydrogen bond dynamics between a 4-MBN and a water molecule. The dynamic quantities we calculated can be divided into two categories: those related to the collective behavior of interfacial water molecules and the H-bond interaction between a water molecule and the CN group of 4-MBN. We found that these two categories of dynamic quantities exhibit opposite trends in response to applied potentials on the Au electrode. We anticipate that the present work will help improve our understanding of the interfacial dynamics of water in various electrolyte systems. [ABSTRACT FROM AUTHOR]

Prior studies have explored the relationship between knee valgus and musculoskeletal variables to formulate injury prevention programs, primarily for females. Nonetheless, there is insufficient evidence pertaining to professional male soccer players. Here, the aim was to test the correlation of lateral trunk inclination, hip adduction, hip internal rotation, ankle dorsiflexion range of motion, and hip isometric strength with knee valgus during the single-leg vertical jump test. Twenty-four professional male soccer players performed a single-leg vertical hop test, hip strength assessments, and an ankle dorsiflexion range of motion test. A motion analysis system was employed for kinematic analysis. Maximal isometric hip strength and ankle dorsiflexion range of motion were tested using a handheld dynamometer and a digital inclinometer, respectively. The correlation of peak knee valgus with peak lateral trunk inclination was.43 during the landing phase (P =.04) and with peak hip internal rotation was −.68 (P <.001). For knee valgus angular displacement, only peak lateral trunk inclination presented a moderate positive correlation (r =.40, P =.05). This study showed that trunk and hip kinematics are associated with knee valgus, which could consequently lead to increased knee overload in male professional soccer players following a unilateral vertical landing test. [ABSTRACT FROM AUTHOR]

We study a united-atom model of the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethyl)sulfonylamide to determine to what extent there exist curves in the phase diagram along which the microscopic dynamics are invariant when expressed in dimensionless, or reduced, form. The initial identification of these curves, termed isodynes, is made by noting that contours of reduced shear viscosity and reduced self-diffusion coefficient coincide to a good approximation. Choosing specifically the contours of reduced viscosity as nominal isodynes, further simulations were carried out for state points on these, and other aspects of dynamics were investigated to study their degree of invariance. These include the mean-squared displacement, shear-stress autocorrelation function, and various rotational correlation functions. These were invariant to a good approximation, with the main exception being rotations of the anion about its long axis. The dynamical features that are invariant have in common that they are aspects that would be relevant for a coarse-grained description of the system; specifically, removing the most microscopic degrees of freedom in principle leads to a simplification of the potential energy landscape, which allows for the existence of isodynes. [ABSTRACT FROM AUTHOR]

The existing early-warning methods primarily rely on detecting structural displacements which are often challenging to measure accurately in real fire scenarios. To develop innovative early-warning strategies, this paper experimentally and numerically investigates the fire-induced collapse of an 8 m × 6 m steel portal frame assembly. Detailed thermo-structural responses of the frame were measured and presented, including the displacements and rotations. The results revealed that the vertical mid-span displacement and horizontal displacement at the rafter end are key to developing an effective early-warning system. Structural rotations seem sensitive to structural deformation and emerges as a valuable safety indicator for structural systems. Furthermore, parametric analyses were carried out in order to investigate the effect of load ratio, fire protection and heating curve on key parameters of the structure subjected to fires. It is discovered that the increased load ratio can reduce the peak value of vertical displacement at the mid-span of the rafter. A rotational angle of 6° in the steel beams is optimal for predicting the collapse of steel portal frames in fire conditions. Based on the parametric studies, an innovative early-warning approach using rotational angles is proposed and validated against the test frame, demonstrating significant applicability and reliability. The rotation-based early-warning approach works in two distinct stages, being activated respectively by the maximum and zero rotational angles at the end of rafter. The early-time ratios for the respective warning stages are 0.65 and 0.88. For better precision and practical reliability, it is further recommended to combine the rotation-based and displacement-based approaches for the on-site early-warning of fire-induced collapse of portal frames. [ABSTRACT FROM AUTHOR]

This work presents a study on the formation of laboratory- scale fire whirls using forest fuels to replicate real-world fire whirls. A total of 48 experiments are conducted using three distinct types of forest fuels, namely Pinus Roxburghii, Shorea Robusta, and Grevillea Robusta, with three fuel pans of diameter 0.2 m, 0.3 m, and 0.4 m, respectively. Different characteristics such as Mass Burning Rate (MBR), Heat Release Rate (HRR), flame height, flame temperature, radiative heat flux and fire effluents are measured for a range of HRRs 40-346 kW and correlations are developed in terms of circulation and diameter. In comparison to free burning, the HRR was found to be increased by 300% with imposed rotation which was further increased up to 65% with fuel rotation. The flame heights are also increased by 30% in the case of imposed rotation and 40% with both imposed and fuel rotation. A detailed measurement of fire effluents revealed that their concentrations for fire whirls were reduced in the range of 50% to 400% compared to free burning fires. Furthermore, the developed correlations were applied to fire whirls of HRRs (up to ∼ 1900 kW) and their validity in predicting the characteristics was ensured. [ABSTRACT FROM AUTHOR]

This paper presents a new approach for designing a superstrate for the Fabry Pérot antenna, to achieve beam steering over the full azimuthal plane. The superstrate of the proposed antenna consists of a linearly graded metasurface (LgMS) and a constant phase partially reflecting surface (PRS). The hybrid metasurfaces offer gradual changes in the magnitude and phase of the reflection and transmission coefficient characteristics, which causes tilting of the main lobe direction.Further, the mechanical rotation of the superstrate structure in the azimuthal plane causes the main lobe direction to steer in the same plane. The proposed antenna operates from 4.33 GHz to 5.1 GHz with a maximum directivity of about 11 dBi and offers beam steering over complete azimuthal plane for frequencies below 4.8 GHz. The proposed structure can be used as a beam steering antenna for applications like air traffic control, satellite communication, shipboard communication, etc. [ABSTRACT FROM AUTHOR]

An underground excavation would lead to the redistribution of not only stress magnitude but also stress direction in the host rock mass. In this paper, an equation was derived to quantify the principal stress orientation rotation angle along the roadway radial direction. Besides, the principal stress orientation rotation gradient was analytically modelled followed by a sensitivity analysis of various influential factors on the principal stress orientation rotation. It was found that the principal stress orientation rotation angle tends to decrease as moving further radially into the rock mass from the excavation surface, where the principal stress rotation angle reaches its maximum value of 90°. Four zones have been classified according to the principal stress orientation rotation gradient including high-frequency , medium-frequency, low-frequency and no rotation zone. Finally, the numerical analysis confirmed the redistribution of the principal stress difference and the rotation angle and provided guidance for optimising the bolts setting angle. [ABSTRACT FROM AUTHOR]

This study investigated a capsule's powder evacuation behavior when rotating about its minor axis in a cross flow and considering the effects of rotation speed and flow rate on powder emission. The experimental platform, an optically accessible capsule chamber, was designed to uncover the independent effects of these variables by enabling high-speed imaging of the powder evacuation. The capsules were rotated at three speeds (1500, 2500, and 3650 RPM) and two constant flow rates, 30 SLPM and 60 SLPM (inlet velocity: 16.67 m/s and 33.33 m/s, respectively). Two powders were selected: a lactose carrier, Respitose (SV010, D50 = 104 µm) and Mannitol (D50 = 7 µm), the latter representing pure active pharmaceutical ingredient formulations that form agglomerates. In addition to imaging, the capsule was weighed before and after each device actuation to quantify powder emission. Increasing the flow rate was found to have the largest impact on the mass emitted from the capsule at all rotation speeds. The emitted mass for all cases was highly variable and influenced by the cohesiveness of the powder and subsequent blockage of the capsule aperture. The potential for blockage was more pronounced for mannitol at the high rotation speeds. Emitted dose over time was modeled using a natural logarithm function to describe the rate of emptying and demonstrate the advantage of increased flow rate and favorability of low/moderate rotation speeds. The study of powder size distribution during evacuation found no significant difference between flow conditions for mannitol, as dispersion was dominated by shearing at the capsule aperture. Copyright © 2025 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Nuclei in the rare-earth region are known to be strongly deformed and show rotational bands up to high spins. Ground state and high spin states of Yb and Er isotopes (N ≥ 100) have been studied using the Hartree–Fock–Bogoliubov approach as well as the projected shell model. A large number of quasiparticle bands are observed in these nuclei and the present study explores the possible origins of some of them. Projected shell model with variable pairing can provide a good description of the ground-state bands up to very high spins. [ABSTRACT FROM AUTHOR]

Nonspherical humeral head implants more closely resemble native humeral anatomy than spherical components and may better replicate native shoulder range of motion (ROM) and kinematics. The purpose of this study was to compare shoulder ROM and kinematics of a commercially available nonspherical humeral head implant with the native humeral head and a height matched, custom manufactured spherical implant. Six fresh frozen cadaveric shoulder specimens were used with a custom shoulder testing system. The native shoulder was tested in multiple positions under anatomic muscle loading. Each specimen was tested for ROM and glenohumeral joint kinematics by measuring the humeral head apex and humeral head center (HHC) translation per degree of rotation using a MicroScribe digitizer. Measurements were then repeated after implantation of a spherical and, subsequently, a nonspherical humeral head prothesis. The nonspherical implant had significantly more internal rotation (IR) compared to the spherical implant at 0° abduction (10.6 ± 6.2° more IR, P =.004, 95% confidence interval [CI]: −13.3, 34.5), 30° abduction (5.7 ± 2.8°, P =.009, 95% CI: −12.6, 24.0) and 60° abduction (6.8 ± 2.7°, P =.002, 95% CI: −8.3, 22.1) in the scapular plane, and 60° abduction (6.9 ± 2.0°, P =.031, 95% CI: −12, 25.6) in the coronal plane. The nonspherical implant had more IR than the native head at 60° of abduction in the scapular plane (7.0 ± 2.2° P =.002, 95% CI: −10.3, 24.3). The spherical head had less IR than the native head at 0° abduction (7.2 ± 4.8°, P =.031, 95% CI: 32.5, 18.1). There were no differences in humeral head apex translation per degree of rotation noted between the spherical implant or nonspherical implant and the native shoulder. The nonspherical head had less HHC translation than the native shoulder at 30° abduction in the forward flexion plane (P =.007); otherwise, there were no statistically significant differences in HHC translation between the native shoulder, the spherical head, and the nonspherical head. There was no significant difference observed between the average difference in anterior-posterior and superior-inferior radius of curvature of the nonspherical implants (2.0 ± 0.7 mm) and the native humeral heads (1.9 ± 1.3 mm) [ P =.926]. The results of this biomechanical study suggest that the commercially available nonspherical humeral head has improved IR when compared to a custom, height controlled spherical implant and offers ROM and kinematics similar to the native humeral head in a cadaveric model. [ABSTRACT FROM AUTHOR]