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With the proliferation of vehicular mobility traces because of inexpensive on-board sensors and smartphones, utilizing them to further understand road movements have become easily accessible. These huge numbers of vehicular traces can be utilized to determine where to enhance road infrastructures such as the deployment of electric vehicle (EV) charging stations. As more EVs are plying today's roads, the driving anxiety is minimized with the presence of sufficient charging stations. By correctly extracting the various transportation parameters from a given dataset, one can design an adequate and adaptive EV charging network that can provide comfort and convenience for the movement of people and goods from one point to another. In this study, we determined the possible EV charging station locations based on an urban city's vehicular capacity distribution obtained from taxi and ride-hailing mobility GPS traces. To achieve this, we first transformed the dynamic vehicular environment based on vehicular capacity into its equivalent urban single snapshot. We then obtained the various traffic zone distributions by initially utilizing k-means clustering to allow flexibility in the total number of wanted traffic zones in each dataset. In each traffic zone, iterative clustering techniques employing Density-based Spatial Clustering of Applications with Noise (DBSCAN) or clustering by fast search and find of density peaks (CFS) revealed various area separation where EV chargers were needed. Finally, to find the exact location of the EV charging station, we last ran k-means to locate centroids, depending on the constraint on how many EV chargers were needed. Extensive simulations revealed the strengths and weaknesses of the clustering methods when applied to our datasets. We utilized the silhouette and Calinski–Harabasz indices to measure the validity of cluster formations. We also measured the inter-station distances to understand the closeness of the locations of EV chargers. Our study shows how CFS + k-means clustering techniques are able to pinpoint EV charger locations. However, when utilizing DBSCAN initially, the results did not present any notable outcome. [ABSTRACT FROM AUTHOR]

The critical role of primary care clinicians (PCCs) in Alzheimer's disease (AD) prevention, diagnosis and management must evolve as new treatment paradigms and disease‐modifying therapies (DMTs) emerge. Our understanding of AD has grown substantially: no longer conceptualized as a late‐in‐life syndrome of cognitive and functional impairments, we now recognize that AD pathology builds silently for decades before cognitive impairment is detectable. Clinically, AD first manifests subtly as mild cognitive impairment (MCI) due to AD before progressing to dementia. Emerging optimism for improved outcomes in AD stems from a focus on preventive interventions in midlife and timely, biomarker‐confirmed diagnosis at early signs of cognitive deficits (i.e. MCI due to AD and mild AD dementia). A timely AD diagnosis is particularly important for optimizing patient care and enabling the appropriate use of anticipated DMTs. An accelerating challenge for PCCs and AD specialists will be to respond to innovations in diagnostics and therapy for AD in a system that is not currently well positioned to do so. To overcome these challenges, PCCs and AD specialists must collaborate closely to navigate and optimize dynamically evolving AD care in the face of new opportunities. In the spirit of this collaboration, we summarize here some prominent and influential models that inform our current understanding of AD. We also advocate for timely and accurate (i.e. biomarker‐defined) diagnosis of early AD. In doing so, we consider evolving issues related to prevention, detecting emerging cognitive impairment and the role of biomarkers in the clinic. [ABSTRACT FROM AUTHOR]

Surface diffusion rates have been simulated using classical molecular dynamics in a model of CO adsorbed on Ni(111). This paper describes the energy distribution among adsorbate modes at the transition state, energy relaxation after crossing the transition state, and correlations among adsorbate modes near the transition state. The adsorbate bending (frustrated rotation) mode is strongly coupled to lateral translational motion. This molecular mode provides an important source of energy for reaching the transition state to diffusion, and an important frictional force that dissipates excess lateral translational energy. In this model, the molecular bending mode is a more important source (and sink) of lateral translational energy than the surface at short times. This result is interpreted as a consequence of directional bonding to the surface, and it should be generally important in surface diffusion of chemisorbed molecules. [ABSTRACT FROM AUTHOR]

The reaction CH4+OH→CH3+H2O has been investigated by ab initio molecular orbital theory with a variety of basis sets and levels of correlation. At the highest level of basis set (Dunning’s correlation consistent) and highest level of correlation [QCISD(T)], the value of ΔH(0) is -13.44 kcal/mol and the classical barrier height is 6.62 kcal/mol which is reduced to 5.24 kcal/mol if zero point effects are included. Transition state theory is used to predict the rate constants and good agreement with the experimental values is found over a broad temperature range. [ABSTRACT FROM AUTHOR]

The aim of this study was to empirically examine the interaction of athlete-specific kinematic kinetic and strength asymmetry in sprint running. Bilateral ground reaction force and kinematic data were collected during maximal velocity (mean = 9.05 m/s) sprinting for eight athletes. Bilateral ground reaction force data were also collected while the same athletes performed maximal effort squat jumps. Using novel composite asymmetry scores, interactions between kinematic and kinetic asymmetry were compared for the group of sprinters. Asymmetry was greater for kinematic variables than step characteristics, with largest respective values of 6.68% and 1.68%. Kinetic variables contained the largest asymmetry values, peaking at >90%. Asymmetry was present in all kinematic and kinetic variables analyzed during sprint trials. However, individual athlete asymmetry profiles were reported for sprint and jump trials. Athletes' sprint performance was not related to their overall asymmetry. Positive relationships were found between asymmetry in ankle work during sprint running and peak vertical force ( r = 0.895) and power ( r = 0.761) during jump trials, suggesting that the ankle joint may be key in regulating asymmetry in sprinting and highlighting the individual nature of asymmetry. The individual athlete asymmetry profiles and lack of relationship between asymmetry of limb strength and sprint performance suggest that athletes are not 'limb dominant' and that strength imbalances are joint and task specific. Compensatory kinetic mechanisms may serve to reduce the effects of strength or biological asymmetry on the performance outcome of step velocity. [ABSTRACT FROM AUTHOR]

This paper evaluates the relationship of blood pressure (BP) levels at Women's Health Initiative (WHI) baseline, treatment of hypertension, and white matter abnormalities among women in conjugated equine estrogen (CEE) and medroxyprogesterone acetate and CEE-alone arms. The WHI Memory Study-Magnetic Resonance Imaging (WHIMS-MRI) trial scanned 1424 participants. BP levels at baseline were significantly positively related to abnormal white matter lesion (WML) volumes. Participants treated for hypertension but who had BP > or = 140/90 mm Hg had the greatest amount of WML volumes. Women with untreated BP > or = 140/90 mm Hg had intermediate WML volumes. Abnormal WML volumes were related to hypertension in most areas of the brain and were greater in the frontal lobe than in the occipital, parietal, or temporal lobes. Level of BP at baseline was strongly related to amount of WML volumes. The results of the study reinforce the relationship of hypertension and BP control and white matter abnormalities in the brain. The evidence to date supports tight control of BP levels, especially beginning at younger and middle age as a possible and perhaps only way to prevent dementia. [ABSTRACT FROM AUTHOR]

The Medical College of Wisconsin (MCW) and the Wisconsin Geriatric Education Center (WGEC) are committed to developing educational materials for primary care physicians in training. In response to the opportunity created by the Accreditation Council for Graduate Medical Education (ACGME) competency mandate, an MCW-led interdisciplinary working group has developed competency-linked video-based assessment tools for use in primary care residency training programs. Modeled after the Objective Structured Clinical Examinations (OSCE), used as part of the medical licensing examination process, we created geriatric-focused Objective Structured Video Examinations (OSVEs) as a strategy to infuse geriatrics into residency training. Each OSVE tool contains a 1-3 minute video trigger that is associated with a series of multiple choice and/or constructed response questions (e.g., fill in the blank). These questions assess residents' understanding of video-demonstrated ACGME competencies including professionalism, systems-based practice, communication, and practice-based learning. An instructor's guide and scoring key are provided for each tool. Response to the OSVEs has been overwhelmingly enthusiastic including greater than 90% commitment by statewide faculty to use the tools in residency training. [ABSTRACT FROM AUTHOR]

Reaction forces experienced by gymnasts swinging on the high bar may be determined indirectly using inverse dynamics analysis or may be measured using strain gauges. The accuracy of inverse dynamics analysis may be poor because of errors in the estimated inertia parameters and in the accelerations obtained from digitized data. On the other hand the use of strain gauges is not always possible in elite competition. This paper presents a method for estimating the reaction forces based on the linear displacements of the bar. The bar was modelled as a point mass attached to horizontal and vertical linear springs (obeying Hooke’s law) with stiffness coefficients determined from static loading. The stiffness coefficients of the bar were determined with three different tensions in the stabilizing cables of the high bar. A force and video analysis of backward giant circles was performed. Estimates for the reaction forces were obtained by multiplying the bar displacements from the video analysis by the stiffness coefficients determined from the static loadings. Comparisons were made between the estimated reaction forces and the reaction forces recorded using strain gauges attached to the high bar. Varying the tension in the stabilizing cables of the high bar did not effect the stiffness of the bar. Root mean squared differences between estimated and recorded reaction forces were on average within 99 N for three ‘regular’ and three ‘accelerated’ giant circles. This was less than 3.5% of the range of forces recorded. The bar displacement method was able to estimate the peak reaction forces to within 7% on average, which compares favourably with 24% reported by Gervais (1993) using inverse dynamics. [ABSTRACT FROM AUTHOR]

Photocell timing systems are used routinely to measure running speeds. In this study, the accuracy of such systems was evaluated using centre of mass speed estimates from three-dimensional video analysis as criteria. One subject ran at five nominal speeds (5-9 m . s-1) for each of five separations (1.6-2.4 m) between consecutive photocells. Running speeds were calculated from the photocell data using single beam and double beam systems. For single beam systems, the start of the first break of a beam and the start of the longest break of a beam were used as trigger criteria. For double beam systems, the first occurrence of both beams being broken and the start of the longest double break were used as trigger criteria. Root mean square speed errors were smaller for the double beam systems. The longest break criterion gave smaller root mean square errors than the first break criterion. In general, errors in speed were smaller for greater photocell separations. An error of 0.1 m . s-1 was achieved using a single beam system set at hip height with a longest break criterion for photocell separations of around two stride lengths. The advantage of using a double beam system is that it achieves this accuracy without the need to adjust photocell separation for different stride lengths. [ABSTRACT FROM AUTHOR]

The optimum pre-flight characteristics of the Hecht and handspring somersault vaults were determined using a two-segment simulation model. The model consisted of an arm segment and a body segment connected by a frictionless pin joint, simulating the vault from the Reuther board take-off through to landing. During horse contact, shoulder torque was set to zero in the model. Five independent pre-flight variables were varied over realistic ranges and an objective function was maximized to find the optimum pre-flight for each vault. The Hecht vault required a low trajectory of the mass centre during pre-flight, with a low vertical velocity of the mass centre and a low angular velocity of the body at horse contact. In contrast, the optimum handspring somersault required a high pre-flight trajectory, with a high angular velocity of the body and a high vertical velocity at horse contact. Despite the simplicity of the model, the optimum pre-flights were similar to those used in competitive performances. [ABSTRACT FROM AUTHOR]

Discusses several research paper presented during the Communications to the Annual Conference of the British Association of Sport and Exercise Science held in Worcester, England. Indirect estimation of peak cable tension during ring longswings; Effect of physical rehabilitation on neuromuscular performance of the knee joint.

The purpose of this study was to investigate the role of the biceps and triceps in rapid elbow extension during the ‘slice’ service in tennis. Six serves, performed by a top male county player (21 years) were studied. Simultaneous cine film (200 Hz) and electromyography (EMG) were used to collect the service data. Impact provided a sonic synchronizing trigger, with biceps and triceps data recorded for a 1 s period before and after the trigger point. Inertia data for the racket were directly determined by a pendulum technique and included in a three segment model of the server's arm. Maximum elbow extension velocities, for the six trials, averaged 44·1, (±3·9) rad7sol;s. Angular velocity values, in the range 24 to 52 rad/s have been reported in tennis and volleyball serving and badminton smashing. Values in excess of 20 rad/s are beyond the contractile velocity range of human skeletal muscle. The contribution of the triceps to rapid forearm extension is therefore questioned. Substantial biceps EMG activity was evident throughout the elbow extension phase, with the peak activity commencing just prior to impact. A powerful stabilizing co-contraction rather than a dominant muscle torque was thus evident at the elbow. Inverse dynamic analysis of the data supported this observation with large resultant internal joint forces, averaging 577 (± 57) N, acting across the elbow joint through impact. The current findings indicate that the triceps activity is more related to elbow stabilization than extension. [ABSTRACT FROM PUBLISHER]

Background Lower limb stability is pivotal to successful dynamic sporting movements, with poor stability during single leg tasks commonly associated with lower limb non-contact injuries. Objective This study investigated stance leg frontal plane stability during a lateral bound task. Design Players performed an infield clinical screening involving 10 alternating bounds from their left (LLEG) and right (RLEG) legs. Each bound comprised stabilisation (landing) and propulsion (lateral push off). 3D kinematic data for the stance leg (200 Hz) were captured using an automated system (CODAmotionTM) and a cluster marker set. Setting Professional footballers currently performing in the English Football League System performed the screening. Participants Five participants performed the screening. Intervention/Assessment of risk factors The independent variables in this study were the players involved. Main outcome measurements Absolute frontal plane sway (AFP-Sway) at the hip, knee and ankle were determined (Visual3DTM) and combined to provide a collective stance leg sway score (CSL-Sway) for each trial. Additionally, percentage contributions of AFP-Sway at each joint to CSL-Sway for all trials were determined and compared across players in each condition using one-way ANOVA. Results There were CSL-Sway differences between players within each condition, accounted for by additional motions at all three lower limb joints under LLEG conditions and only hip and knee joints under RLEG conditions. Percentage individual joint contributions to CSL-Sway differed between players at the knee and ankle joints under LLEG and all joints under RLEG conditions. Both conditions revealed two distinct bounding strategies with hip or combination of hip and ankle motions contributing the most to CSL-Sway. Conclusions Player differences in CSL-Sway, AFP-Sway and percentage joint contribution to CSL-Sway under both bounding conditions highlight the individualised nature of lateral bound strategies. Such objective assessment of stance leg stability may enable movement stability classification and ultimately aid injury risk identification. [ABSTRACT FROM PUBLISHER]