Tracking Measurements Research Articles

Long-term Effectiveness and Outcome-Determining Factors of Arthroscopic Bankart Repair for Recreational Sports Population: An Assessment of 100 Patients With a Mean Follow-up of 12.7 Years

Background: A limited number of studies have reported the long-term effectiveness of and associated factors for recurrence of anterior shoulder instability after arthroscopic Bankart repair (ABR). Purpose: To report the long-term clinical outcomes after ABR in a recreational sports population and identify the associated factors that influence the final instability status. Study Design: Case series; Level of evidence, 4. Methods: A retrospective study was performed in patients treated with ABR between 2007 and 2013 by a single surgeon. Patient data, magnetic resonance imaging measurements of bone loss and glenoid track, and intra- and perioperative factors were analyzed. After a minimum follow-up of 10 years, patient-reported outcomes including the Western Ontario Shoulder Instability Index score, the Rowe score, the visual analog scale for pain and function, the American Shoulder and Elbow Surgeons score, and sports activity were assessed. The current instability status was classified into 3 groups: stable, apprehensive, and redislocated. These groups were statistically compared with respect to outcomes and associated factors. Results: A total of 100 patients with a mean age of 22.4 ± 5.5 years and a mean follow-up of 12.7 ± 2.1 years were included. At the final follow-up, 38 patients (38%) showed recurrent symptoms: 19 patients (19%) with subjective apprehension and 19 patients (19%) with redislocation, including 10 patients (10%) with revision surgery. At the final follow-up, the redislocated group showed the lowest patient-reported outcomes and return to sports (both P < .001). The apprehensive group also showed a lower Western Ontario Shoulder Instability Index score (P = .011), Rowe score (P = .003), American Shoulder and Elbow Surgeons score (P = .027), and return to sports (P = .005) than the stable group. Participation in contact sports (P = .026), glenoid bone loss (P = .005), size of Hill-Sachs lesion (P = .009), and off-track lesions (P = .016) were all associated with recurrent symptoms, whereas age <20 years (P = .012), participation in contact sports (P = .003), and off-track lesions (P = .042) were associated with redislocation. Conclusion: After long-term follow-up in a recreational sports population, ABR demonstrated a 19% rate of subjective apprehension and 19% rate of redislocation, with a gradual decline in clinical outcomes and sports activity over time. Therefore, candidates for ABR should be selected based on consideration of risk factors such as off-track lesions, age <20 years, and participation in contact sports.

Application of Rosette Quorum Sensing Inhibitor in Fish Preservation

This study screened fish derived spoilage bacteria as the research object, and a development approach was used to determine the inhibitory effect of rose polyphenols on the secretion of the quorum sensing (QS) signal molecule N-acyl homoserine lactone (AHLs) by fish spoilage bacteria. The effect of rose QS inhibitors applied to fish preservation coatings on the putrefaction of spoilage bacteria was studied by measuring the changes in texture, pH, and thiobarbituric acid reactive substances (TBARS) during the storage process of fish. The findings demonstrated that the dominant strain causing fish spoilage was Sphingomonaspaucimobilis, and rose polyphenols could significantly inhibit the ability of the spoilage bacteria to secrete AHLs. The application of different concentrations (1 and 2 mg/mL) of rose polyphenols in fish preservation coatings can slow down the growth of TBARS, and 2 mg/mL of rose polyphenols has a better inhibitory effect on the oxidation of fish fat, By measuring the L*, a*, and b* values of different treatment groups, it was found that the addition of rose polyphenols delayed the decrease of L* and the increase of a* value in fish meat, but had no significant effect on b* value, The 2 mg/mL rose polyphenol coating treatment group had the slightest pH change, according on tracking measurements of pH changes during fish storage. The sensory assessment results of fish meat from different treatment groups during storage showed that the 2 mg/mL rose polyphenol treatment group decreased the least among all treatment groups, which means applying it to the fish meat preservation coating can effectively delay the rate of quality decline during storage. The findings of this work may serve as a theoretical foundation for the use of naturally occurring rose polyphenols, a QS inhibitor, in the preservation of fish.

Railway sleeper vibration measurement by train‐borne laser Doppler vibrometer and its speed‐dependent characteristics

AbstractA train‐borne laser Doppler vibrometer (LDV) directly measures the dynamic response of railway track components from a moving train, which has the potential to complement existing train‐borne technologies for railway track monitoring. This paper proposes a holistic methodology to characterize train‐borne LDV measurements by combining computer‐aided approaches and real‐life measurements. The focus is on the speed‐dependent characteristics because the train speed affects the intensity of railway sleeper vibrations and the intensity of speckle noise, which further affects the quality and usability of the measured signals. First, numerical models are established and validated to simulate sleeper vibrations and speckle noise separately. Then, a vibration–noise separation method is proposed to effectively extract speckle noise and structural vibrations from LDV signals measured at different speeds. The parameters of the separation method are tuned using simulation signals. The method is then validated using laboratory measurements in a vehicle‐track test rig and applied to field measurements on a railway track in Rotterdam, the Netherlands. Further, the speed‐dependent characteristics of train‐borne LDV measurement are determined by analyzing the competition between sleeper vibrations and speckle noise at different speeds. Simulation and measurement results show that an optimal speed range yields the highest signal‐to‐noise ratio, which varies for different track structures, measurement configurations, and operational conditions. The findings demonstrate the potential of train‐borne LDV for large‐scale rail infrastructure monitoring.

Time-efficient etching of LR-115 SSNTD film for indoor radon, thoron quantification.

LR-115 Solid State Nuclear Track Detector (SSNTD) is commonly utilized for quantifying indoor radon-thoron levels, by tallying the tracks formed in the films by exposure to these gases. Conventionally, sodium hydroxide (NaOH) is used to etch LR-115 films for 90 min at 60°C. However, this study suggests a time-efficient alternative approach utilizing potassium hydroxide (KOH) as the etchant. In an initial investigation, the bulk etch rates of KOH were examined at different normalities and temperatures, revealing that KOH exhibited nearly double the bulk etch rates compared to NaOH. Subsequently, a specially designed controlled experiment was conducted to assess the efficacy of the technique by enumerating the tracks generated in the films. Both etchants demonstrated very similar track counts for identical controlled exposures, indicating the reliability of the method. A consistent behavior was observed in the real-case scenario of LR-115 films exposed indoors to alpha particles from radon and its decay products. In both experiments, the etching with KOH for 45 min gave track densities comparable to standard NaOH etching for 90 min, highlighting the time efficiency of this method. Investigations were carried out into track shape and size features, aspects crucial to the measurement technique, using microscopic imaging of samples treated with both etchants. Strikingly similar track shapes and sizes were observed, affirming the consistency in the track measurement technique. Collectively, these findings suggest that KOH etchant reduces the etching time, presenting itself as a time-efficient method for quantifying radon and thoron track density.

Noncoherent Channel Combining for GNSS Signal Tracking with an Adaptive Antenna Array

Adaptive antenna arrays are widely used to protect Global Navigation Satellite System (GNSS) receivers from interference. However, conventional blind anti-jamming array processing methods can cause satellite signal attenuation, which reduces signal tracking precision and measurement accuracy. To alleviate this problem, this paper proposes the noncoherent channel combining method for GNSS signal tracking with an adaptive antenna array. A two-stage processing architecture is applied in the proposed method, where the first stage implements interference suppression, and the second stage achieves noncoherent channel combining. The proposed method has the advantage of blind characteristics that can be implemented without any other auxiliary information. It also reveals a unified processing architecture for anti-jamming array processing methods. Thus, a detailed comparison and analysis of the proposed method with several typical blind anti-jamming methods is performed. Simulation results demonstrate the effectiveness of the proposed method and its superiority over existing methods in terms of tracking performance.

Rapid and Precise Measurement Method for Track Static Geometry of Large-Span Bridge Railway

Track geometry is an important parameter reflecting the safety of bridge railway, which is of great significance for the structure control of railway track. The measurement of track geometry is an indispensable part of structural health monitoring for bridge railway. However, existing methods for track static track geometry measurement are inadequate in terms of accuracy and efficiency. In order to improve the measurement method, this paper proposes a rapid and precise measurement method based on IMU/odometer aided by multiple total stations, which has the advantages of high efficiency, high accuracy, and is less affected by the environment. The proposed method uses a track measurement trolley (TMT) integrated with IMU and an odometer to collect railway track data on the bridge, and multiple total stations are used to synchronously measure the three-dimensional coordinates of the TMT. After coordinate system registration and time synchronisation, the data are then fused using a filtering algorithm to finally obtain the static geometry of the railway track. The proposed method was validated on the NanSha Port Railway Bridge across the Xijiang River in Foshan, China, and the results showed that the proposed method can make a single on-orbit measurement of a 1000 m length of large-span bridge railway track within half an hour, with an accuracy on the order of millimetres. The proposed method has obvious advantages in terms of efficiency and accuracy and is therefore an effective new measurement method with practical significance.

Assessment of environmental forensic indicator for anthropogenic groundwater contamination via target/suspect/nontarget analysis using HRMS techniques

This study compared target/suspect/nontarget analysis via liquid chromatography-high-resolution mass spectrometry (LC-HRMS) with traditional environmental forensic methods, specifically nitrate and its stable N isotope, in assessing groundwater pollution from livestock manure and agriculture. Using an in-house database of 1471 target and suspects, 35 contaminants (pesticides, veterinary drugs, surfactants) were identified, some uniquely linked to specific pollution sources, such as sulfamethazine and 4-formylaminoantipyrine in manure-affected areas. Pesticides were widespread, typically showing higher intensity in agricultural zones. On the other hand, the results of stable N isotope analysis (δ15N-NO3: 4.8 to 16.4‰) indicated the influence of human activities such as fertilizers, sewage, and manure in all sampling sites, including the control site far from the pollution sources and cannot differentiate the specific sources. The study underscores LC-HRMS's efficacy in different pollution sources, surpassing the limitations of stable N isotope analysis, and provides valuable insights for polluted groundwater source tracking strategies.

Research on High Speed Particle Tracking Measurement Method Based on Ultra High Speed Pulse Camera

Research on High Speed Particle Tracking Measurement Method Based on Ultra High Speed Pulse Camera

Autonomic and facial electromyographic responses to watching eyes.

We measured participants' psychophysiological responses and gaze behavior while viewing a stimulus person's direct and averted gaze in three different conditions manipulating the participants' experience of being watched. The results showed that skin conductance responses and heart rate deceleration responses were greater to direct than averted gaze only in the condition in which the participants had the experience of being watched by the other individual. In contrast, gaze direction had no effects on these responses when the participants were manipulated to believe that the other individual could not watch them or when the stimulus person was presented in a pre-recorded video. Importantly, the eye tracking measures showed no differences in participants' looking behavior between these stimulus presentation conditions. The results of facial electromyography responses suggested that direct gaze elicited greater zygomatic and periocular responses than averted gaze did, independent of the presentation condition. It was concluded that the affective arousal and attention-orienting indexing autonomic responses to eye contact are driven by the experience of being watched. In contrast, the facial responses seem to reflect automatized affiliative responses which can be elicited even in conditions in which seeing another's direct gaze does not signal that the self is being watched.

Large range automatic attitude measurement method for laser tracking measurement

Large range automatic attitude measurement method for laser tracking measurement

Enhancing the lifetime and vacuum tribological performance of PVD-MoS2 coatings by nitrogen modification

As a solid lubricant, MoS2 is used for reducing friction and wear in machine elements under challenging operating conditions. In application, service life is thus a decisive factor that depends on the coating. Here, the effect of gaseous nitrogen modification on the performance of physical vapor deposited MoS2 coatings has been studied under vacuum conditions. The coatings were modified chemically or in their structural design by varying the bias voltage alternately. Tribologically induced changes were identified in short-running and long-running intermittent ball-on-disc tests, while the lifetime was evaluated in ball-on-disc tests until coating failure, with a coefficient of friction value exceeding 0.3 defined as the failure criterion. Furthermore, the microstructure was investigated before and after tribological loading. It appeared from scanning electronic microscopic imaging, that nitrogen modification reduced the initial degree of porosity and material compacting occurred after a short tribological loading. Nanoindentation measurements in the wear track of the compacted coating supported these results by a significant increase in indentation hardness and indentation modulus. Overall, the improvement in lubrication performance due to nitrogen modification led to a significant extension of service life, whereas the chemical and structural modification exhibited the highest service life of the coating.

Youth Ending the HIV Epidemic (YEHE): Protocol for a pilot of an automated directly observed therapy intervention with conditional economic incentives among young adults with HIV.

Young adults have a disproportionately high rate of HIV infection, high rates of attrition at all stages of the HIV care continuum, and an elevated probability of disease progression and transmission. Tracking and monitoring objective measures of antiretroviral therapy (ART) adherence in real time is critical to bolster the accuracy of research data, support adherence, and improve clinical outcomes. However, adherence monitoring often relies on self-reported and retrospective data or requires additional effort from providers to understand individual adherence patterns. In this study, we will monitor medication-taking using a real-time objective measure of adherence that does not rely on self-report or healthcare providers for measurement. The Youth Ending the HIV Epidemic (YEHE) study will pilot a novel automated directly observed therapy-conditional economic incentive (aDOT-CEI) intervention to improve ART adherence among youth with HIV (YWH) in California and Florida who have an unsuppressed HIV viral load. The aDOT app uses facial recognition to record adherence each day, and then economic incentives are given based on a participant's confirmed adherence. We will enroll participants in a 3-month pilot study to assess the feasibility and acceptability of the aDOT-CEI intervention using predefined metrics. During and after the trial, a subsample of the pilot participants and staff/providers from participating AIDS Healthcare Foundation (AHF) clinics will participate in individual in-depth interviews to explore intervention and implementation facilitators and barriers. YEHE will provide data on the use of an aDOT-CEI intervention to improve adherence among YWH who are not virologically suppressed. The YEHE study will document the feasibility and acceptability and will explore preliminary data to inform a trial to test the efficacy of aDOT-CEI. This intervention has the potential to effectively improve ART adherence and virologic suppression among a key population experiencing health disparities. The trial registration number is NCT05789875.

Super-resolution imaging for the detection of low-energy ion tracks in fine-grained nuclear emulsions

We propose a new wide-field imaging method that exploits the Localized Surface Plasmon Resonance phenomenon to produce super-resolution images with an optical microscope equipped with a custom design polarization analyzer module. In this paper we describe the method and apply it to the analysis of low-energy carbon ion tracks implanted in a nuclear emulsion film. The result is then compared with the measurements of the same tracks carried out at an electronic microscope. The images set side by side show their close similarity. The resolution achieved with the current microscope setup is estimated to be about 50 nm.

Validation of cost-efficient EEG experimental setup for neural tracking in an auditory attention task

When individuals listen to speech, their neural activity phase-locks to the slow temporal rhythm, which is commonly referred to as “neural tracking”. The neural tracking mechanism allows for the detection of an attended sound source in a multi-talker situation by decoding neural signals obtained by electroencephalography (EEG), known as auditory attention decoding (AAD). Neural tracking with AAD can be utilized as an objective measurement tool for diverse clinical contexts, and it has potential to be applied to neuro-steered hearing devices. To effectively utilize this technology, it is essential to enhance the accessibility of EEG experimental setup and analysis. The aim of the study was to develop a cost-efficient neural tracking system and validate the feasibility of neural tracking measurement by conducting an AAD task using an offline and real-time decoder model outside the soundproof environment. We devised a neural tracking system capable of conducting AAD experiments using an OpenBCI and Arduino board. Nine participants were recruited to assess the performance of the AAD using the developed system, which involved presenting competing speech signals in an experiment setting without soundproofing. As a result, the offline decoder model demonstrated an average performance of 90%, and real-time decoder model exhibited a performance of 78%. The present study demonstrates the feasibility of implementing neural tracking and AAD using cost-effective devices in a practical environment.

Evaluation of bicyclist physiological response and visual attention in commercial vehicle loading zones

IntroductionWith growing freight operations throughout the world, there is a push for transportation systems to accommodate trucks during loading and unloading operations. Currently, many urban locations do not provide loading and unloading zones, which results in trucks parking in places that obstruct bicyclist’s roadway infrastructure (e.g., bicycle lanes). MethodTo understand the implications of these truck operations, a bicycle simulation experiment was designed to evaluate the impact of commercial vehicle loading and unloading activities on safe and efficient bicycle operations in a shared urban roadway environment. A fully counterbalanced, partially randomized, factorial design was chosen to explore three independent variables: commercial vehicle loading zone (CVLZ) sizes with three levels (i.e., no CVLZ, Min CVLZ, and Max CVLZ), courier position with three levels (i.e., no courier, behind the truck, beside the truck), and with and without loading accessories. Bicyclist’s physiological response and eye tracking were used as performance measures. Data were obtained from 48 participants, resulting in 864 observations in 18 experimental scenarios using linear mixed-effects models (LMM). ResultsResults from the LMMs suggest that loading zone size and courier position had the greatest effect on bicyclist’s physiological responses. Bicyclists had approximately two peaks-per-minute higher when riding in the condition that included no CVLZ and courier on the side compared to the base conditions (i.e., Max CVLZ and no courier). Additionally, when the courier was beside the truck, bicyclist’s eye fixation durations (sec) were one (s) greater than when the courier was located behind the truck, indicating that bicyclists were more alert as they passed by the courier. The presence of accessories had the lowest influence on both bicyclists’ physiological response and eye tracking measures. Practical ApplicationsThese findings could support better roadway and CVLZ design guidelines, which will allow our urban street system to operate more efficiently, safely, and reliable for all users.

Dynamic accommodation measurement using Purkinje reflections and machine learning

Quantifying eye movement is important for diagnosing various neurological and ocular diseases as well as AR/VR displays. We developed a simple setup for real-time dynamic gaze tracking and accommodation measurements based on Purkinje reflections, which are the reflections from front and back surfaces of the cornea and the eye lens. We used an accurate eye model in ZEMAX to simulate the Purkinje reflection positions at different focus distances of the eye, which matched the experimental data. A neural network was trained to simultaneously predict vergence and accommodation using data collected from 9 subjects. We demonstrated that the use of Purkinje reflection coordinates in machine learning resulted in precise estimation. The proposed system accurately predicted the accommodation with an accuracy better than 0.22 D using subject’s own data and 0.40 D using other subjects’ data with two-point calibration in tests performed with 9 subjects in our setup.

Comparison of Eye Tracking and Teller Acuity Cards for Visual Acuity Assessment in Pediatric Cortical/Cerebral Visual Impairment

To compare eye tracking and Teller acuity cards (TAC) for assessment of visual acuity in children with cortical, or cerebral, visual impairment (CVI). Reliability and validity study. We recruited 41 children with CVI from a single academic pediatric neuro-ophthalmology clinic. All children performed eye tracking to measure visual acuity, and 26 children completed TAC assessment by a masked examiner. Additionally, 2 pediatric neuro-ophthalmologists graded visual behavior using the 6-level Visual Behavior Scale (VBS). Eye tracking and TAC were performed at baseline and at 1 month. Test-retest reliability of eye tracking and TAC were assessed using the intraclass correlation coefficient (ICC). Eye tracking and TAC visual acuities were correlated with one another and VBS scores using the Spearman correlation coefficient. Test-retest reliability was excellent for eye tracking measurement of visual acuity (ICC = 0.81, P < .0001). For pediatric CVI, TAC test-retest reliability was fair (ICC = 0.42, P = .04). There was a moderate correlation between eye tracking and TAC (r = 0.43, P = .03) and between TAC and VBS score (r = 0.50, P = .009), and a strong correlation between eye tracking grating acuity and VBS score (r = 0.72, P < .0001). In our cohort of children with CVI, grating acuity measured by eye tracking demonstrated higher test-retest reliability and stronger correlation with pediatric neuro-ophthalmologic assessment of visual behavior than Teller acuity. Objective determination of gaze direction by an eye tracking camera may be more accurate than human assessment in this population. Future research is needed to determine the optimal methods of longitudinal assessment of visual function and functional vision in children with CVI.

Tracking and Tracing in Israel during COVID-19

Abstract In March 2020, the Israeli government decided that its internal security agency may collect, process, and use technological information measures to tackle the spread of COVID-19. This was done by tracking the cellphones of those who may have contracted the virus, along with obtaining details on those who were in proximity for more than fifteen minutes and fourteen days prior to the positive outcome of those traced. The article discusses the controversial track and trace measure and proposes an alternative model of using tracing technology, considering the obligation to preserve human life and the right to individual privacy among other rights and liberties. It is argued that measures infringing on the right to privacy must be effectively restricted in time and meet standards of necessity, proportionality, and scientific validity, as required by constitutional standards. The government needs to balance the right to health against the right to privacy.

Comparison of modern 3D measurement methods for special tasks of shipbuilding industry

Research presents modern technologies of 3D measurements in shipbuilding production parts. Special template of the keel detail was made for the research. The detail measurements with a laser tracker, laser scanning, industrial photogrammetry and handheld scanning are performed. Leica Absolute Tracker AT960-LR was used for Laser tracker measurements. Laser scanning was performed with Z+F Imager 5010. Nikon D2Xs photo camera was used for Industrial photogrammetry. Handheld scanner DPI-7 from DotProduct was also used for 3D measurements of the details. All collected data were imported into 3DReshaper software for comparison. The accuracy comparison for the specific equipment used in the study is performed. The recommendations for optimal equipment use and software products in this research are also included. The authors also present the assessment of the cost and time spent on the measurements.

Strong Resemblance between Surface and Deep Zonal Winds inside Jupiter Revealed by High-degree Gravity Moments

Jupiter’s atmosphere interior is a coupled fluid dynamical system strongly influenced by the rapid background rotation. While the visible atmosphere features east–west zonal winds on the order of ∼100 m s−1, zonal flows in the dynamo region are significantly slower, on the order of ∼cm s−1 or less, according to the latest magnetic secular variation analysis. The vertical profile of the zonal flows and the underlying mechanism remain elusive. The latest Juno radio tracking measurements afforded the derivation of Jupiter’s gravity field to spherical harmonic degree 40. Here, we use the latest gravity solution to reconstruct Jupiter’s deep zonal winds without a priori assumptions about their latitudinal profile. The pattern of our reconstructed deep zonal winds strongly resemble that of the surface wind within ±35° latitude from the equator, in particular the northern off-equatorial jet (NOEJ) and the southern off-equatorial jet. The reconstruction features larger uncertainties in the southern hemisphere due to the north–south asymmetric nature of Juno's trajectory. The amplitude of the reconstructed deep NOEJ matches that of the surface wind when the wind is truncated at a depth ∼2500 km, and becomes twice that of the surface wind if the truncation depth is reduced to ∼1500 km. Our analysis supports the physical picture in which a prominent part of the surface zonal winds extends into Jupiter’s interior significantly deeper than the water cloud layer.