Continuous Motion Research Articles

A Novel Method for Tracking Neck Motions Using a Skin-Conformable Wireless Accelerometer: A Pilot Study

Introduction: Cervical spine disease is a leading cause of pain and disability. Degenerative conditions of the spine can result in neurologic compression of the cervical spinal cord or nerve roots and may be surgically treated with an anterior cervical discectomy and fusion (ACDF) in up to 137,000 people per year in the United States. A common sequelae of ACDF is reduced cervical range of motion (CROM) with patient-based complaints of stiffness and neck pain. Currently, tools for assessment of CROM are manual, subjective, and only intermittently utilized during doctor or physical therapy visits. We propose a skin-mountable acousto-mechanic sensor (ADvanced Acousto-Mechanic sensor; ADAM) as a tool for continuous neck motion monitoring in postoperative ACDF patients. We have developed and validated a machine learning neck motion classification algorithm to differentiate between eight neck motions (right/left rotation, right/left lateral bending, flexion, extension, retraction, protraction) in healthy normal subjects and patients. Methods: Sensor data from 12 healthy normal subjects and 5 patients were used to develop and validate a Convolutional Neural Network (CNN). Results: An average algorithm accuracy of 80.0 ± 3.8% was obtained for healthy normal subjects (94% for right rotation, 98% for left rotation, 65% for right lateral bending, 87% for left lateral bending, 89% for flexion, 77% for extension, 50% for retraction, 84% for protraction). An average accuracy of 67.5 ± 5.8% was obtained for patients. Discussion: ADAM, with our algorithm, may serve as a rehabilitation tool for neck motion monitoring in postoperative ACDF patients. Sensor-captured vital signs and other events (extubation, vocalization, physical therapy, walking) are potential metrics to be incorporated into our algorithm to offer more holistic monitoring of patients after cervical spine surgery.

Sonata Form as Temporal Process: the First Movement of Bruckner's Sixth symphony

ABSTRACTThe timeworn view that Bruckner's sonata form is a motionless architecture devoid of dynamic processes has long contributed his isolation from the mainstream post‐Beethovenian tradition. Taking inspiration from August Halm's (1914) and Ernst Kurth's (1925) approaches, which were aimed at overcoming this view, this article seeks to elucidate the processual aspects of Bruckner's symphonic form in light of recent theoretical developments in musical form. Specifically, it combines William Caplin's form‐functional theory (1998), especially its beginning–middle–end paradigm, with Matthew Arndt's (2018) reconception of formal functionality to construct a new framework for the analysis of Bruckner's symphonic forms.By way of an analytical case study of the first movement of Bruckner's Sixth Symphony, the article reveals that the expression of continuous motion occurring across discrete formal entities, often further dramatised by ‘wave dynamics’ (Kurth 1925), is fundamental to Bruckner's reinvigoration of sonata form's inherent temporal process in a post‐Romantic context. In the exposition, the inter‐thematic beginning, middle and end paradigms are redistributed to the three thematic groups, which express their unique temporal domain while delineating a continuous tonal journey from the home key to the subordinate key. The remainder of the movement articulates a gradual journey of homecoming, with each subsequent large‐scale part addressing previously suggested tonal implications. Ultimately, the modified form‐functional approach adopted in this study sheds light on Bruckner's exceptional care for formal syntax on various levels of structure, and its close association with an overarching, though unconventional, tonal plot.

CFD-DEM-based evaluation of main-channel sediment transport processes subject to supplement from a steep tributary

The accumulation of sediments within mountainous gullies serves as a significant source for the main channel. Understanding the transport characteristics is crucial for comprehending reach-scale sediment supply features and channel morphodynamics. This study addresses the previously unexplored challenges in accurately quantifying variations in sediment transport rates, particularly during critical transitions such as the mobilization of static sediment pulses into continuous motion. To accomplish this objective, a combined Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) computational framework is employed to directly simulate the detailed trajectories of all particles. After validating the CFD-DEM model, we examine the effects of three major influential factors (particle size, channel slope and channel width) on sediment transport characteristics. The results indicate that the sediment transport rate exhibits rapid rise to peak followed by gradual attenuation process, described by a long-tail effect. The cross-sectional averaged sediment transport rate positively correlates with the width of sediment transport belt. The downstream propagation of sediment is enhanced by steeper channel slope and narrower channel width. In addition, we find that cross-sectional averaged sediment transport rate controlled by these factors exhibits inherent self-similarity. The temporal variation of dimensionless sediment transport rate for a certain section can be modeled by a modified two-branch Weibull function encompasses three model parameters dependent on influential factors and longitudinal location. The parameter variation of the functional model, combined with linear variation of the three main influencing factors, provides support for explaining sediment transport processes in channels of dimensions different from those studied. These findings enhance the understanding of the formation and evolution mechanism of sediment transport induced by upstream loose deposit destruction.

Continuous‐dilated temporal and inter‐frame motion excitation feature learning for gait recognition

AbstractThe authors present global‐interval and local‐continuous feature extraction networks for gait recognition. Unlike conventional gait recognition methods focussing on the full gait cycle, the authors introduce a novel global‐ continuous‐dilated temporal feature extraction (TFE) to extract continuous and interval motion features from the silhouette frames globally. Simultaneously, an inter‐frame motion excitation (IME) module is proposed to enhance the unique motion expression of an individual, which remains unchanged regardless of clothing variations. The spatio‐temporal features extracted from the TFE and IME modules are then weighted and concatenated by an adaptive aggregator network for recognition. Through the experiments over CASIA‐B and mini‐OUMVLP datasets, the proposed method has shown the comparable performance (as 98%, 95%, and 84.9% in the normal walking, carrying a bag or packbag, and wearing coats or jackets categories in CASIA‐B, and 89% in mini‐OUMVLP) to the other state‐of‐the‐art approaches. Extensive experiments conducted on the CASIA‐B and mini‐OUMVLP datasets have demonstrated the comparable performance of our proposed method compared to other state‐of‐the‐art approaches.

The Philosophy of Probability Value Behavior: Fractions and Composite Probability Functions in the Continuous Case

This paper focuses on probability value behavior in the case of continuous sample space by employing fractions intervals and composite functions. The study evaluates value behavior rather than finding values directly, which involves utilization of some concepts from continuity, geometric probability, and measure theory. This paper primarily uses an experiment that contains two major events, head H and tail T, in all their occurrence phases. This spread in infinite and uncountable fractions by a continuous motion within intervals and in the predominant circumstances where events are probabilistic values. As a result, every circumstance reflects many important characteristics of probability theory. Among the main results, this paper provides proven propositions that help design experiments upon understanding the case nature, with some explanations to the existing relation between probability value and the case nature. Also, this paper provides a proven corollary that allows visualizing negative probability values as a particular trial. This in turn proposes necessary uses for the composite probability function P_j 〖(p〗_i). Moreover, this paper provides numerical explanations of limits, which can demonstrate the nature of P_j 〖(p〗_i), alongside some techniques. Also, this paper considered conditional probability through some corollaries and the possibility of using the non-negative function of the interval i, alongside many important results in form of discussions.

Vibration mitigation using dual-open and infilled trenches in layered soil media: Field tests and numerical simulations

Ground-borne vibrations are increasing at a rapid rate due to the rise in urban expansion and industrial activities. The current solution to mitigate the unwanted vibrations is limited to the use of single trenches that require unrealistic depths. This paper presents the possibilities of using dual open and infilled trenches to mitigate the vibrations generated due to continuous harmonic motions. Full-scale field tests and comprehensive numerical studies were performed to systematically design dual trenches. The field vibration tests were performed under a wide range of frequencies using the Lazan-type mechanical oscillator. Similarly, numerical studies have been performed using finite element analysis software, PLAXIS 2D. Expanded polystyrene (EPS) geofoams of different densities, bentonite, ceramsite, concrete, and sand-rubber mixture were used as the infill materials. The normalized depths of 0.40 and 0.50 were observed as the optimal values to reach an average amplitude reduction ratio (average ARR) of 0.25 for the dual open and EPS15-infilled trenches, respectively. The isolation efficiency of EPS15-infilled trenches was observed to be 178 % higher compared to the EPS48-infilled trenches. The performance difference between EPS15 and ceramsite-filled dual trenches was observed to be only 4 % in terms of average ARR, the former being superior.

Soft crawling robot integrated with liquid metal-based flexible strain sensor and closed-loop feedback control

Due to the inherent softness and adaptability, soft robots have shown great application prospects in medical rehabilitation, environmental exploration, and other fields. However, the unpredictable and complex behaviors of the elastic materials greatly increased the difficulty in the control of soft robots. This study proposed an integrated soft crawling robot (ISCR) with flexible strain sensors to achieve the closed-loop feedback control of motion. First, a flexible strain sensor was fabricated by injecting liquid metal (LM) into an elastomer with a wavy structure. The key performances of the sensor were investigated. The developed flexible strain sensor can achieve a high gauge factor of 2.07, a low hysteresis of 1.902%, a wide detection range of 150% strain, a low detection limitation as low as 0.4% strain change, and an excellent stability and durability, which fully satisfy the requirements for the proprioception of soft robots. We built a closed-loop feedback control system to achieve closed-loop control of the ISCR. Finally, we successfully realized the continuous motion of the ISCR under closed-loop control. We believe this work will be helpful for the development of automation and intelligence of soft crawling robots.

Increased lesion detectability in patients with locally advanced breast cancer—A pilot study using dynamic whole-body [18F]FDG PET/CT

BackgroundAccurate diagnosis of axillary lymph node (ALN) metastases is essential for prognosis and treatment planning in breast cancer. Evaluation of ALN is done by ultrasound, which is limited by inter-operator variability, and by sentinel lymph node biopsy and/or ALN dissection, none of which are without risks and/or long-term complications. It is known that conventional 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) has limited sensitivity for ALN metastases. However, a recently developed dynamic whole-body (D-WB) [18F]FDG PET/CT scanning protocol, allowing for imaging of tissue [18F]FDG metabolic rate (MRFDG), has been shown to have the potential to increase lesion detectability. The study purpose was to examine detectability of malignant lesions in D-WB [18F]FDG PET/CT compared to conventional [18F]FDG PET/CT.ResultsThis study prospectively included ten women with locally advanced breast cancer who were referred for an [18F]FDG PET/CT as part of their diagnostic work-up. They all underwent D-WB [18F]FDG PET/CT, consisting of a 6 min single bed dynamic scan over the chest region started at the time of tracer injection, a 64 min dynamic WB PET scan consisting of 16 continuous bed motion passes, and finally a contrast-enhanced CT scan, with generation of MRFDG parametric images. Lesion visibility was assessed by tumor-to-background and contrast-to-noise ratios using volumes of interest isocontouring tumors with a set limit of 50% of SUVmax and background volumes placed in the vicinity of tumors. Lesion visibility was best in the MRFDG images, with target-to-background values 2.28 (95% CI: 2.04–2.54) times higher than target-to-background values in SUV images, and contrast-to-noise values 1.23 (95% CI: 1.12–1.35) times higher than contrast-to-noise values in SUV images. Furthermore, five imaging experts visually assessed the images and three additional suspicious lesions were found in the MRFDG images compared to SUV images; one suspicious ALN, one suspicious parasternal lymph node, and one suspicious lesion located in the pelvic bone.ConclusionsD-WB [18F]FDG PET/CT with MRFDG images show potential for improved lesion detectability compared to conventional SUV images in locally advanced breast cancer. Further validation in larger cohorts is needed.Clinical trial registrationThe trial is registered in clinicaltrials.gov, NCT05110443, https://www.clinicaltrials.gov/study/NCT05110443?term=NCT05110443&rank=1.

Modeling Continuous Motion for 3D Point Cloud Object Tracking

The task of 3D single object tracking (SOT) with LiDAR point clouds is crucial for various applications, such as autonomous driving and robotics. However, existing approaches have primarily relied on appearance matching or motion modeling within only two successive frames, thereby overlooking the long-range continuous motion property of objects in 3D space. To address this issue, this paper presents a novel approach that views each tracklet as a continuous stream: at each timestamp, only the current frame is fed into the network to interact with multi-frame historical features stored in a memory bank, enabling efficient exploitation of sequential information. To achieve effective cross-frame message passing, a hybrid attention mechanism is designed to account for both long-range relation modeling and local geometric feature extraction. Furthermore, to enhance the utilization of multi-frame features for robust tracking, a contrastive sequence enhancement strategy is proposed, which uses ground truth tracklets to augment training sequences and promote discrimination against false positives in a contrastive manner. Extensive experiments demonstrate that the proposed method outperforms the state-of-the-art method by significant margins on multiple benchmarks.

Delayed surgical treatment of Pipkin type II fracture in a patient with infection COVID-19. A case report

A 25-year-old man with a hip dislocation and Pipkin II type femoral head fracture, whose surgical treatment was postponed for 15 days due to Covid 19 pandemic, is described. For 2 months after surgery, treatment was supported by therapy in a hyperbaric chamber and with a continuous passive motion (CPM) splint. Four months after surgery, bone fusion of the femoral head fracture was achieved with its normal revascularization. Two years after the operation, the patient was moving efficiently and had no complaints of hip pain. Delayed open reduction and internal fixation of the femoral head fracture resulted in a very good functional and radiological outcome.

Disc Degeneration and Cervical Spine Intervertebral Motion: A Cross-Sectional Study in Patients with Neck Pain and Matched Healthy Controls.

While neck pain can be defined in clinical terms, in most cases the underlying pathophysiology is largely unknown. Regional cervical spine range of motion is often found to be reduced in patients with neck pain compared to persons without pain although it is not clear if the decreased range is cause or effect. Less is known about the role of intervertebral kinematics and how that might be related to the presence of disc degeneration. In this study, the prevalence of intervertebral disc degeneration and continuous cervical intervertebral motion were both measured utilizing quantitative fluoroscopy (QF) in patients with subacute or chronic neck pain (n = 29) and gender-matched healthy controls (n = 30). A composite disc degeneration (CDD) score was calculated for each participant from the first, neutral, lateral fluoroscopic image. Intervertebral motion sharing parameters of motion-sharing inequality (MSI) and motion-sharing variability (MSV) were derived from the active cervical motion sequences obtained while patients were seated. The objective was to determine if average age, CDD, MSI, and MSV values were correlated and if there were differences in these variables between the neck pain group and the healthy control group. Correlation analysis was conducted for age, CDD, MSI, and MSV in each group. Age was moderately correlated with MSV in cervical spine extension in patients only (r = 0.63, p < 0.001). There were no significant differences in the prevalence of disc degeneration (CDD) between patients, who had on average mild pain and related disability, and healthy controls (median CDD 2 both groups, p = 0.94). There were also no significant differences in either flexion or extension intervertebral motion-sharing inequality or variability (MSI or MSV) between groups as measured during active cervical motion.

Gait pattern can alter aesthetic visual impression from a third-person perspective

Beauty is related to our lives in various ways and examining it from an interdisciplinary approach is essential. People are very concerned with their appearance. A widely accepted beauty ideal is that the thinner an individual is, the more beautiful they are. However, the effect of continuous motion on body form aesthetics is unclear. Additionally, an upright pelvic posture in the sagittal plane during walking seems to affect the aesthetic judgments of female appearance. We directly analyzed the influence of body form and walking pattern on aesthetic visual impressions from a third-person perspective with a two-way analysis of variance. Captured motion data for three conditions—upright pelvis, normal pelvis, and posteriorly tilted pelvic posture—were applied to each of three mannequins, representing thin, standard, and obese body forms. When participants watched stimulus videos of the mannequins walking with various postures, a significantly higher score for aesthetic visual impression was noted for an upright pelvic posture than for a posteriorly tilted pelvic posture, irrespective of body form (F(2, 119) = 79.89, p < 0.001, η2 = 0.54). These findings show that the third-person perspective of beauty can be improved even without being thin by walking with an upright pelvic posture.

Design of integral backstepping controller - sliding mode along with admittance controller of knee joint robot in the presence of noise

Robots are increasingly being used in rehabilitation to assist patients with physical disabilities, particularly the knee joint. Physiotherapists often practice the patient’s leg around the knee joint to strengthen the muscles. However, Continuous Passive Motion (CPM) devices face challenges such as lack of feedback and resistance. This thesis aims to address these issues by using admittance and impedance concepts to control the robot’s flexible behavior against individual foot forces. The research uses a combination of backstepping and admittance algorithms, Model Reference Adaptive Control (MRAC), Sliding-Backstepping and Admittance Control to create a soft interactive patient-robot interaction. The device is designed for both left and right legs.

Try This for Size: Multi-Scale Teleportation in Immersive Virtual Reality.

The ability of a user to adjust their own scale while traveling through virtual environments enables them to inspect tiny features being ant-sized and to gain an overview of the surroundings as a giant. While prior work has almost exclusively focused on steering-based interfaces for multi-scale travel, we present three novel teleportation-based techniques that avoid continuous motion flow to reduce the risk of cybersickness. Our approaches build on the extension of known teleportation workflows and suggest specifying scale adjustments either simultaneously with, as a connected second step after, or separately from the user's new horizontal position. The results of a two-part user study with 30 participants indicate that the simultaneous and connected specification paradigms are both suitable candidates for effective and comfortable multi-scale teleportation with nuanced individual benefits. Scale specification as a separate mode, on the other hand, was considered less beneficial. We compare our findings to prior research and publish the executable of our user study to facilitate replication and further analyses.

Newsworthy Nature: Capturing Exotic Birds in Buffon’s France

Abstract: Today, with the effects of climate change and the information revolution, nature is viewed as especially newsworthy. However, news about nature has a deeper history. An important precedent was Buffon’s popular ornithological project (1770s–80s). In its wake, the kingdom of France experienced an avalanche of newspaper reports on birds and public displays of reportedly exotic and rare birds found by amateurs. Though initially a top-down endeavor of knowledge production, Buffon’s project incited a burgeoning reading public to transform themselves from passive recipients of data about the natural world into active amateur scientists producing, perhaps for the first time, a network of actors who crowd-sourced knowledge about a natural species that was at once ubiquitous and in continuous motion. Compassing the global universe of birds was both an effect of, and a captivating metaphor for, the acceleration of social mobility and transnational networking in late eighteenth-century France.

Optimal Cooperative Eco-Driving of Multitrain With TLET Comprehensive System

Aiming to minimize the total electricity usage in realistic operation of urban rail transit (URT) trains, this paper establishes the coupled model for the train-line-electric network-timetable (TLET) comprehensive system, and proposes a multi-train cooperative eco-driving method to achieve the system energy optimal. The dynamic power flow within the DC railway system with multiple trains is analyzed by modeling the traction power supply system (TPSS), and an improved power flow calculation (PFC) method is proposed to calculate the dynamic power flow distribution. To achieve the total substation energy minimization, a space-time-speed (STS) three-dimensional network is presented to transform continuous train motion process into discrete states on space-speed plane, and a multiple individuals dynamic programming (MIDP) algorithm is throughly developed to cooperatively optimize the multi-train trajectories along the time horizon, with which the optimal speed profiles and timetables of each train can be obtained simultaneously. Moreover, a computationally efficient heuristic algorithm together with a train-to-train (T2T) communication policy are developed as a comparative study. Numerical experiment with field data from Guangzhou Metro Line 8 is implemented, to illustrate the energy-saving performance of the proposed methods.

A light-powered self-rotating liquid crystal elastomer drill

Self-oscillating systems can directly convert ambient energy to mechanical work, and new type self-oscillating systems are worth designing for applications in energy harvesters, engines, and actuators. Taking inspiration from the hand drill, we have developed a novel self-rotating drill system, which is consist of a turnplate and a liquid crystal elastomer (LCE) fiber under steady illumination. To investigate the self-rotating behaviors of the LCE drill, we have proposed a nonlinear theoretical model of the LCE drill under steady illumination based on the well-established dynamic LCE model. Numerical calculation reveals that the LCE drill can undergo a supercritical Hopf bifurcation between the static regime and the self-rotation regime. The self-rotation of drill originates from the contraction of winding portion of LCE fiber in illumination at winding state, and its continuous periodic motion is sustained by the interrelation between light energy and damping dissipation. The Hopf bifurcation conditions are also investigated in detail, as well as the vital system parameters affecting its frequency and amplitude. In contrast to the abundant existing self-oscillating systems, this self-rotating drill stands out due to its simple and lightweight structure, customizable dimensions, and high speed, and thus facilitates the design of compact and integrated systems, enhancing their applicability in microdevices and systems. This bears great significance in fields like micro-robotics, micro-sensors, and medical instruments, enabling the realization of smaller and higher-performance devices.

Investigating the impact of pillar shape on flexible erythrocyte separation through deterministic lateral displacement

The deterministic lateral displacement (DLD) method has gradually moved beyond the separation of spherical rigid particles and has been successfully applied to the field of biological cells, especially to the separation of disc-shaped flexible erythrocytes. Different shapes of micropillars in the DLD device significantly affect the sorting performance of erythrocytes. We investigated the effect of the flow field in the gap of micropillars of different shapes (circular, triangular, I-shaped) on the behavior of erythrocyte tumbling motion. The simulation results showed that in the I-shaped pillar DLD device, compared with the circular and triangular pillars, the erythrocytes exhibited a stable and continuous flipping motion during the movement along the array offset direction, which enabled the effective separation size to be maintained at a high level. In addition, the formula for calculating the critical diameter of the I-shaped pillar DLD array for separating erythrocytes was obtained by fitting, which provides strong support for a more efficient design of the I-shaped pillar DLD device dedicated to erythrocyte sorting.

Evaluation of cyclic fatigue behavior of RACE EVO rotary Files: In-vitro comparative study

IntroductionComparative evaluation of the newly introduced; RACE EVO file system to the currently well-performing file systems like HyFlex EDM OneFile, Vortex Blue, ProTaper Gold (PTG) with regards to the cyclic fatigue resistance. Materials&Methods.The endodontic rotary files under evaluation were segregated into four groups as follows:; RACE EVO, PTG, Vortex Blue, and HyFlex EDM OneFile. A detailed physical analysis of the cyclic fatigue resistance was performed in 15 files of each type (n = 60). Under the test conditions of 37 °C the test samples were subjected to continuous motion at the manufacturer recommended speed within an artificial curved canal until it fractured. For all the test samples, with the recording of time of fracture, calculation was done for number of cycles to fracture (NCF). In addition, the length of the fractured segment was determined. The fractured surface was further evaluated with scanning electron microscopic (SEM) images. ResultsHighest significance for NCF was seen in HyFlex EDM OneFile followed by the Vortex Blue, PTG, and; RACE EVO (p < 0.05) by analyzing the data statistically. Significant differences among the lengths of the fractured segments were evident among tested files, ranging between 4.73 and 6.3 mm (p < 0.05) with HyFlex EDM OneFile uniquely differentiating from the others showing the fracture at 6.3 mm. The common features of cyclic fatigue failure was further substantiated by SEM images. ConclusionsCompared to the HyFlex EDM OneFile, Vortex Blue, and PTG files; RACE EVO demonstrated significantly lower resistance to cyclic fatigue.

Effects of an Early Exercise Program with Cryotherapy on Range of Motion, Pain, Swelling, and Gait in Patients with Total Knee Arthroplasty: A Randomized Controlled Trial.

Background: This study aimed to investigate the effects of cryotherapy on range of motion, pain, swelling, and gait in patients who underwent total knee arthroplasty. Methods: Forty-three patients who underwent TKA (total knee arthroplasty) and met the inclusion criteria were randomly divided into two groups. The experimental (n = 21) and control (n = 22) groups underwent cryotherapy and non-cryotherapy treatments, respectively, six times a week for two weeks, and once each before and after exercise for 3 min. Both groups followed a similar initial rehabilitation exercise program using a continuous passive motion device. Results: The results showed a significant difference in knee flexion range of motion, pain, edema, and 10 MWT comparisons from pre- to post-test (p < 0.001). The above values were also significantly different in the comparison between the two groups (p < 0.05). Conclusions: Therefore, this study confirmed that an initial rehabilitation exercise program accompanied by cryotherapy could be an effective intervention method for range of motion, pain, edema, and walking in patients undergoing total knee arthroplasty.