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1.
Scand J Psychol ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38951995

ABSTRACT

Whether compensation serves as a motivational resource for employees is still a debated subject. It has been suggested that the effect of pay on motivation could be contingent on the satisfaction of the basic psychological needs as outlined by self-determination theory. The current research explored the role of amount of base pay as well as pay fairness discrepancy in relation to basic psychological need satisfaction, autonomous work motivation and, in turn, psychological well-being (i.e., vigor and emotional exhaustion), turnover intentions, and work performance. Managerial need support was also included in the model, so its mechanisms and its effects on the outcomes could be measured against those of pay. Using a combination of archival data and employees' self-reports from 593 Norwegian workers, results revealed that amount of base pay did not predict satisfaction of any of the basic needs, pay fairness discrepancy negatively predicted satisfaction of the needs for autonomy and relatedness and positively predicted satisfaction of the need for competence, whereas managerial need support significantly predicted satisfaction of all three needs. While there was no significant direct relation from amount of base pay to any of the outcomes, results showed a significant direct relation from managerial need support to psychological well-being (positive to vigor and negative to emotional exhaustion) and turnover intentions (negative). There was also a significant direct positive relation from pay fairness discrepancy to turnover intentions.

2.
Data Sci Sci ; 3(1)2024.
Article in English | MEDLINE | ID: mdl-38947225

ABSTRACT

In mediation analysis, the exposure often influences the mediating effect, i.e., there is an interaction between exposure and mediator on the dependent variable. When the mediator is high-dimensional, it is necessary to identify non-zero mediators M and exposure-by-mediator ( X -by- M ) interactions. Although several high-dimensional mediation methods can naturally handle X -by- M interactions, research is scarce in preserving the underlying hierarchical structure between the main effects and the interactions. To fill the knowledge gap, we develop the XMInt procedure to select M and X -by- M interactions in the high-dimensional mediators setting while preserving the hierarchical structure. Our proposed method employs a sequential regularization-based forward-selection approach to identify the mediators and their hierarchically preserved interaction with exposure. Our numerical experiments showed promising selection results. Further, we applied our method to ADNI morphological data and examined the role of cortical thickness and subcortical volumes on the effect of amyloid-beta accumulation on cognitive performance, which could be helpful in understanding the brain compensation mechanism.

3.
Z Med Phys ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38960810

ABSTRACT

PURPOSE: To apply velocity selective arterial spin labeling (VSASL) combined with a navigator-based (NAV) prospective motion compensation method for a free-breathing liver perfusion measurement without contrast agent. METHODS: Sinc-modulated Velocity Selective Inversion (sinc-VSI) pulses were applied as labeling and control pulses. In order to account for respiratory motion, a navigator was employed in the form of a single gradient-echo projection readout, located at the diaphragm along the inferior-superior direction. Prior to each transverse imaging slice of the spin-echo EPI based readouts, navigator and fat suppression were incorporated. Motion data was obtained from the navigator and transmitted back to the sequence, allowing real-time adjustments to slice positioning. The sinc-VSI without velocity-selective gradients during the control condition but with velocity-selective gradients along all three directions during labeling was chosen for the VSASL. The VSASL was compared with pseudo-continuous ASL (pCASL) methods, which selectively tagged the moving spins using a tagging plane placed at the portal vein and hepatic artery. RESULTS: The motion caused by respiratory activity was effectively computed using the navigator signal. The coefficients of variation (CoV) of average liver voxel in NAV were significantly decreased when compared to breath-hold (BH), with an average reduction of 29.4 ±â€¯18.44% for control images, and 29.89 ±â€¯20.83% for label images (p < 0.001). The resulting maps of normalized ASL signal (normalized to M0) showed significantly higher perfusion weightings in the NAV-compensated VSASL, when compared to the NAV-compensated pCASL techniques. CONCLUSIONS: This study demonstrates the feasibility of using a navigator-based prospective motion compensation technique in conjunction with VSASL for the measurement of liver perfusion without the use of contrast agents while allowing for free-breathing.

4.
Med Image Anal ; 97: 103254, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38968908

ABSTRACT

The present standard of care for unresectable liver cancer is transarterial chemoembolization (TACE), which involves using chemotherapeutic particles to selectively embolize the arteries supplying hepatic tumors. Accurate volumetric identification of intricate fine vascularity is crucial for selective embolization. Three-dimensional imaging, particularly cone-beam CT (CBCT), aids in visualization and targeting of small vessels in such highly variable anatomy, but long image acquisition time results in intra-scan patient motion, which distorts vascular structures and tissue boundaries. To improve clarity of vascular anatomy and intra-procedural utility, this work proposes a targeted motion estimation and compensation framework that removes the need for any prior information or external tracking and for user interaction. Motion estimation is performed in two stages: (i) a target identification stage that segments arteries and catheters in the projection domain using a multi-view convolutional neural network to construct a coarse 3D vascular mask; and (ii) a targeted motion estimation stage that iteratively solves for the time-varying motion field via optimization of a vessel-enhancing objective function computed over the target vascular mask. The vessel-enhancing objective is derived through eigenvalues of the local image Hessian to emphasize bright tubular structures. Motion compensation is achieved via spatial transformer operators that apply time-dependent deformations to partial angle reconstructions, allowing efficient minimization via gradient backpropagation. The framework was trained and evaluated in anatomically realistic simulated motion-corrupted CBCTs mimicking TACE of hepatic tumors, at intermediate (3.0 mm) and large (6.0 mm) motion magnitudes. Motion compensation substantially improved median vascular DICE score (from 0.30 to 0.59 for large motion), image SSIM (from 0.77 to 0.93 for large motion), and vessel sharpness (0.189 mm-1 to 0.233 mm-1 for large motion) in simulated cases. Motion compensation also demonstrated increased vessel sharpness (0.188 mm-1 before to 0.205 mm-1 after) and reconstructed vessel length (median increased from 37.37 to 41.00 mm) on a clinical interventional CBCT. The proposed anatomy-aware motion compensation framework presented a promising approach for improving the utility of CBCT for intra-procedural vascular imaging, facilitating selective embolization procedures.

5.
Anal Chim Acta ; 1316: 342820, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-38969422

ABSTRACT

This research presents an innovative reflective fiber optic probe structure, mutinously designed to detect H7N9 avian influenza virus gene precisely. This innovative structure skillfully combines multimode fiber (MMF) with a thin-diameter seven-core photonic crystal fiber (SCF-PCF), forming a semi-open Fabry-Pérot (FPI) cavity. This structure has demonstrated exceptional sensitivity in light intensity-refractive index (RI) response through rigorous theoretical and experimental validation. The development of a quasi-distributed parallel sensor array, which provides temperature compensation during measurements, has achieved a remarkable RI response sensitivity of up to 532.7 dB/RIU. The probe-type fiber optic sensitive unit, expertly functionalized with streptavidin, offers high specificity in detecting H7N9 avian influenza virus gene, with an impressively low detection limit of 10-2 pM. The development of this biosensor marks a significant development in biological detection, offering a practical engineering solution for achieving high sensitivity and specificity in light-intensity-modulated biosensing. Its potential for wide-ranging applications in various fields is now well-established.


Subject(s)
Biosensing Techniques , Influenza A Virus, H7N9 Subtype , Temperature , Biosensing Techniques/methods , Influenza A Virus, H7N9 Subtype/genetics , Influenza A Virus, H7N9 Subtype/isolation & purification , Optical Fibers , Limit of Detection , Fiber Optic Technology/methods , Animals , Genes, Viral
6.
Ultrasonics ; 142: 107387, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38971005

ABSTRACT

The ultrasonic pulse-echo technique is widely employed to measure the wall thickness reduction due to corrosion in pipelines. Ultrasonic monitoring is noninvasive and can be performed online to evaluate the structural health of pipelines. Although ultrasound is a robust technique, it presents two main difficulties arising from the temperature variation in the medium being monitored: the mechanical assembly must have high stability and the ultrasonic propagation velocity must take into account the temperature variation. In this paper, a detailed strategy is presented to compensate for changes in the propagation velocity whenever the temperature changes. The method is considered self-compensated because the calibration data is obtained from the ultrasonic signals captured using the pipe under evaluation. The analysis of systematic errors in the temperature compensation is presented, first considering that a reference initial pipe thickness is given, and second when a reference sound velocity is given. The technique was evaluated under laboratory conditions using a closed loop with accelerated corrosion through the use of continuous flow saline water containing sand. In this test, the ultrasonic results were compared with the traditional coupon method used to determine corrosion loss. The results show that the self-compensated method was able to compensate for temperature fluctuations, and the total thickness loss measured by the ultrasound technique was close to the value measured by the coupons. Finally, the measurement system was tested in a production pipeline exposed to sunlight. The results show that the self-compensated method can reduce the oscillations in the thickness loss readings, caused by temperature swings, but large temperature variations cannot be completely compensated for. This experiment also shows the effects of low mechanical stability, which caused completely invalid results.

7.
Public Health Nurs ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38967307

ABSTRACT

OBJECTIVE: To investigate the impact of yoga on successful aging based on the selection, optimization, and compensation model in elderly women. DESIGN: Quasi-experimental study. SAMPLE: Seniors' meeting points and parks and clubs for the old age pensioners of the ministry of education, ministry of healthcare, and the oil corporation in Shiraz, Iran. 68 elderly women within the age range of 60-86 years were divided into a yoga and a control group. MEASUREMENTS: The subjects in both groups were asked to complete the selection, optimization, and compensation model questionnaire before and after the intervention. Successful aging was measured using the selection, optimization, and compensation questionnaire. INTERVENTION: The yoga training program was implemented in 1-h sessions twice a week for eight weeks. RESULTS: After eight weeks of yoga training, the results showed a significant difference between the pretest and posttest successful aging total scores of the yoga group (P = .005). However, the difference between the yoga and control groups' posttest mean total scores was not significant (P = .601). CONCLUSION: Based on the results, it seems that yoga training can improve successful aging. Thus, yoga is recommended as an inexpensive and entertaining method.

8.
Insect Mol Biol ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949741

ABSTRACT

Transcriptomic data have been used to study sex chromosome dosage compensation (SCDC) in approximately 10 Lepidoptera ZW species, yielding a consensus compensation pattern of Z ≈ ZZ < AA . $$ \approx \mathrm{ZZ}<\mathrm{AA}. $$ It remains unclear whether this compensation pattern holds when examining more Lepidoptera ZW species and/or using proteomic data to analyse SCDC. Here we combined transcriptomic and proteomic data as well as transcriptional level of six individual Z genes to reveal the SCDC pattern in Helicoverpa armigera, a polyphagous lepidopteran pest of economic importance. Transcriptomic analysis showed that the Z chromosome expression of H. armigera was balanced between male and female but substantially reduced relative to autosome expression, exhibiting an SCDC pattern of Z ≈ ZZ < AA $$ \approx \mathrm{ZZ}<\mathrm{AA} $$ . When using H. amigera midgut proteomic data, the SCDC pattern of this species changed from Z ≈ ZZ < AA $$ \approx \mathrm{ZZ}<\mathrm{AA} $$ at transcriptomic level to Z = ZZ = AA at the proteomic level. RT-qPCR analysis of transcript abundance of six Z genes found that compensation for each Z gene could vary from no compensation to overcompensation, depending on the individual genes and tissues tested. These results demonstrate for the first time the existence of a translational compensation mechanism, which is operating in addition to a translational mechanism, such as has been reported in other lepidopteran species. And the transcriptional compensation mechanism functions to accomplish Z chromosome dosage balance between the sexes (M = F on the Z chromosome), whereas the translation compensation mechanism operates to achieve dosage compensation between Z chromosome and autosome (Z = AA).

9.
Obes Sci Pract ; 10(4): e775, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38979094

ABSTRACT

Background: Rising obesity rates in the workforce are accompanied by a hidden cost burden to employers due to work productivity loss. Understanding the impact of obesity on work productivity is essential for employers to provide tailored weight loss interventions in the workplace. Objectives: To measure work loss and associated productivity costs among employees with overweight/obesity compared with employees with normal weight. Methods: This retrospective cohort study used the MerativeTM MarketScan® Health and Productivity Management Database to identify adult employees with ≥1 diagnosis code reporting a body mass index (BMI) between 1/1/2015-12/31/2019. Based on the earliest BMI, employees were assigned to normal weight (BMI 19-24.9), overweight (BMI 25-29.9), obesity class 1 (BMI 30-34.9), obesity class 2 (BMI 35-39.9), and obesity class 3 (BMI ≥40) cohorts. Among employees with data for each work loss category (absenteeism, short-term disability [STD], long-term disability [LTD], worker's compensation [WC]) during the 12-month follow-up, the percentage of employees with work loss, number of hours/days lost, and associated productivity costs were reported. Results: 719,482 employees (normal weight: 106,631, overweight: 230,637, obesity class 1: 185,850, obesity class 2: 101,909, obesity class 3: 94,455) were included. Outcomes increased with each higher BMI category for the mean number of absence hours ([in order of BMI category]: 262, 273, 285, 290, 304) and percentage of employees with a claim (STD: 6.8%, 7.6%, 9.7%, 11.7%, 17.0%; LTD: 0.4%, 0.4%, 0.5%, 0.6%, 0.8%; WC: 2.7%, 2.8%, 3.4%, 3.6%, 3.5%). Estimated costs to the employer associated with absenteeism, STD, LTD, and WC were $1,036, $611, $38, and $95 higher per year (respectively) in the obesity class 3 cohort relative to the normal weight cohort. Conclusions: This real-world analysis demonstrated that employees with overweight/obesity had higher loss of work productivity compared with employees with normal weight. Further studies are warranted to determine the long-term impacts on work productivity loss if overweight and obesity are left untreated.

10.
Front Hum Neurosci ; 18: 1412921, 2024.
Article in English | MEDLINE | ID: mdl-38979100

ABSTRACT

Transcranial focused ultrasound enables precise and non-invasive manipulations of deep brain circuits in humans, promising to provide safe and effective treatments of various neurological and mental health conditions. Ultrasound focused to deep brain targets can be used to modulate neural activity directly or localize the release of psychoactive drugs. However, these applications have been impeded by a key barrier-the human skull, which attenuates ultrasound strongly and unpredictably. To address this issue, we have developed an ultrasound-based approach that directly measures and compensates for the ultrasound attenuation by the skull. No additional skull imaging, simulations, assumptions, or free parameters are necessary; the method measures the attenuation directly by emitting a pulse of ultrasound from an array on one side of the head and measuring with an array on the opposite side. Here, we apply this emerging method to two primary future uses-neuromodulation and local drug release. Specifically, we show that the correction enables effective stimulation of peripheral nerves and effective release of propofol from nanoparticle carriers through an ex vivo human skull. Neither application was effective without the correction. Moreover, the effects show the expected dose-response relationship and targeting specificity. This article highlights the need for precise control of ultrasound intensity within the skull and provides a direct and practical approach for addressing this lingering barrier.

11.
Cell Rep ; 43(7): 114456, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38990722

ABSTRACT

The rearrangement and expression of the immunoglobulin µ heavy chain (Igh) gene require communication of the intragenic Eµ and 3' regulatory region (RR) enhancers with the variable (VH) gene promoter. Eµ binding of the transcription factor YY1 has been implicated in enhancer-promoter communication, but the YY1 protein network remains obscure. By analyzing the comprehensive proteome of the 1-kb Eµ wild-type enhancer and that of Eµ lacking the YY1 binding site, we identified the male-specific lethal (MSL)/MOF complex as a component of the YY1 protein network. We found that MSL2 recruitment depends on YY1 and that gene knockout of Msl2 in primary pre-B cells reduces µ gene expression and chromatin looping of Eµ to the 3' RR enhancer and VH promoter. Moreover, Mof heterozygosity in mice impaired µ expression and early B cell differentiation. Together, these data suggest that the MSL/MOF complex regulates Igh gene expression by augmenting YY1-mediated enhancer-promoter communication.

12.
J Cogn Psychother ; 38(3): 227-242, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38991741

ABSTRACT

Increased emphasis has been placed on elucidating the contribution of client variables, such as treatment preference, to optimize evidence-based practice. This analog study sought to better understand variables associated with treatment preference using a convenience sample of college students (n = 54) who read brief descriptions of three interventions for negative thoughts-defusion, noticing, and restructuring. They rated each on acceptability and practicality and completed measures of cognitive fusion, emotional distress, and experiential avoidance as possible moderating variables. Restructuring was overwhelmingly preferred and rated as more acceptable than the two alternatives by both the overall sample and a distressed subsample. Preference for defusion or noticing was not predicted by ratings of acceptability or practicality but by elevated levels of cognitive fusion and emotional distress consistent with a compensation model. Limitations of the study and its implications for further research on psychotherapy preference and its integration within evidence-based practice are discussed.


Subject(s)
Patient Preference , Humans , Male , Female , Young Adult , Adult , Psychotherapy , Cognitive Behavioral Therapy
13.
Sci Rep ; 14(1): 16072, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38992076

ABSTRACT

Aiming at the problem of zero sequence voltage generated by unbalance parameters of line to ground, which affects arc suppression effect of grounding fault of controllable voltage source. By analyzing the influence of ground unbalance parameters on the arc suppression effect of controllable voltage source under different grounding modes, the mechanism of full compensation arc suppression based on zero sequence voltage of neutral point is revealed, and on this basis, a fully compensated arc suppression model of controllable voltage source controlled by double closed loop PI is established, and the deviation control is carried out by using the neutral voltage of distribution network and the voltage of fault phase supply. The residual voltage ring adopts the ground fault phase residual voltage for closed loop control. The simulation results show that the dual-closed-loop PI control algorithm can continuously stabilize the output waveform of the controllable voltage source. When the transition resistance is 0.1 ~ 10 kΩ, the residual voltage stabilization time of the independent controllable voltage source grounding method is 43 ms ~ 2.4 s, and the parallel arc suppression coil grounding method is 43 ms ~ 4.7 s. The proposed dual closed-loop PI control method for neutral point voltage deviation and fault residual voltage can stabilize the residual voltage of the grounded fault phase to below 10 V, forcing reliable arc extinction at the grounded fault point, exhibiting good stability. Low-voltage simulation tests have also proved the feasibility of the algorithm.

14.
Cell Genom ; : 100607, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38996479

ABSTRACT

Chondrichthyes is an important lineage to reconstruct the evolutionary history of vertebrates. Here, we analyzed genome synteny for six chondrichthyan chromosome-level genomes. Our comparative analysis reveals a slow evolutionary rate of chromosomal changes, with infrequent but independent fusions observed in sharks, skates, and chimaeras. The chondrichthyan common ancestor had a proto-vertebrate-like karyotype, including the presence of 18 microchromosome pairs. The X chromosome is a conversed microchromosome shared by all sharks, suggesting a likely common origin of the sex chromosome at least 181 million years ago. We characterized the Y chromosomes of two sharks that are highly differentiated from the X except for a small young evolutionary stratum and a small pseudoautosomal region. We found that shark sex chromosomes lack global dosage compensation but that dosage-sensitive genes are locally compensated. Our study on shark chromosome evolution enhances our understanding of shark sex chromosomes and vertebrate chromosome evolution.

15.
Magn Reson Med ; 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38997801

ABSTRACT

PURPOSE: Diffusion encoding gradient waveforms can impart intra-voxel and inter-voxel dephasing owing to bulk motion, limiting achievable signal-to-noise and complicating multishot acquisitions. In this study, we characterize improvements in phase consistency via gradient moment nulling of diffusion encoding waveforms. METHODS: Healthy volunteers received neuro ( N = 10 $$ N=10 $$ ) and cardiac ( N = 10 $$ N=10 $$ ) MRI. Three gradient moment nulling levels were evaluated: compensation for position ( M 0 $$ {M}_0 $$ ), position + velocity ( M 1 $$ {M}_1 $$ ), and position + velocity + acceleration ( M 1 + M 2 $$ {M}_1+{M}_2 $$ ). Three experiments were completed: (Exp-1) Fixed Trigger Delay Neuro DWI; (Exp-2) Mixed Trigger Delay Neuro DWI; and (Exp-3) Fixed Trigger Delay Cardiac DWI. Significant differences ( p < 0 . 05 $$ p<0.05 $$ ) of the temporal phase SD between repeated acquisitions and the spatial phase gradient across a given image were assessed. RESULTS: M 0 $$ {M}_0 $$ moment nulling was a reference for all measures. In Exp-1, temporal phase SD for G z $$ {G}_z $$ diffusion encoding was significantly reduced with M 1 $$ {M}_1 $$ (35% of t-tests) and M 1 + M 2 $$ {M}_1+{M}_2 $$ (68% of t-tests). The spatial phase gradient was reduced in 23% of t-tests for M 1 $$ {M}_1 $$ and 2% of cases for M 1 + M 2 $$ {M}_1+{M}_2 $$ . In Exp-2, temporal phase SD significantly decreased with M 1 + M 2 $$ {M}_1+{M}_2 $$ gradient moment nulling only for G z $$ {G}_z $$ (83% of t-tests), but spatial phase gradient significantly decreased with only M 1 $$ {M}_1 $$ (50% of t-tests). In Exp-3, M 1 + M 2 $$ {M}_1+{M}_2 $$ gradient moment nulling significantly reduced temporal phase SD and spatial phase gradients (100% of t-tests), resulting in less signal attenuation and more accurate ADCs. CONCLUSION: We characterized gradient moment nulling phase consistency for DWI. Using M1 for neuroimaging and M1 + M2 for cardiac imaging minimized temporal phase SDs and spatial phase gradients.

16.
Sensors (Basel) ; 24(13)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-39000925

ABSTRACT

Dark-and-weak-target simulators are used as ground-based calibration devices to test and calibrate the performance metrics of star sensors. However, these simulators are affected by full-field-of-view energy nonuniformity. This problem impacts the quality of output images and the calibration accuracy of sensors and inhibits further improvements in navigational accuracy. In the study reported in this paper, we sought to analyze the factors which affect full-field-of-view energy uniformity in dark-and-weak-target simulators. These include uneven irradiation in backlight sources, the leakage of light from LCD display panels, and the vignetting of collimating optical systems. We then established an energy transfer model of a dark-and-weak-target simulator based on the propagation of a point light source and proposed a self-adaptive compensation algorithm based on pixel-by-pixel fitting. This algorithm used a sensor to capture the output image of a dark-and-weak-target simulator and iteratively calculated the response error matrix of the simulator. Finally, we validated the feasibility and effectiveness of the compensation algorithm by acquiring images using a self-built test system. The results showed that, after compensating an output image of the dark-and-weak-target simulator, the grayscale standard display function (SDF) of the acquired sensor image was reduced by about 50% overall, so the acquisition image was more accurately compensated, and the desired level of grayscale distribution was obtained. This study provides a reference for improving the quality of output images from dark-and-weak-target simulators, so that the working environments of star sensors may be more realistically simulated, and their detection performance improved.

17.
Sensors (Basel) ; 24(13)2024 Jul 03.
Article in English | MEDLINE | ID: mdl-39001111

ABSTRACT

Space targets move in orbit at a very high speed, so in order to obtain high-quality imaging, high-speed motion compensation (HSMC) and translational motion compensation (TMC) are required. HSMC and TMC are usually adjacent, and the residual error of HSMC will reduce the accuracy of TMC. At the same time, under the condition of low signal-to-noise ratio (SNR), the accuracy of HSMC and TMC will also decrease, which brings challenges to high-quality ISAR imaging. Therefore, this paper proposes a joint ISAR motion compensation algorithm based on entropy minimization under low-SNR conditions. Firstly, the motion of the space target is analyzed, and the echo signal model is obtained. Then, the motion of the space target is modeled as a high-order polynomial, and a parameterized joint compensation model of high-speed motion and translational motion is established. Finally, taking the image entropy after joint motion compensation as the objective function, the red-tailed hawk-Nelder-Mead (RTH-NM) algorithm is used to estimate the target motion parameters, and the joint compensation is carried out. The experimental results of simulation data and real data verify the effectiveness and robustness of the proposed algorithm.

18.
ISA Trans ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-39013690

ABSTRACT

This study discusses a finite-time compensation tracking control method for a rehabilitative training walker. The dynamic model with input dead zone was constructed to describe the walker, and a finite-time disturbance forces observation method was proposed based on the impact mechanism on tracking performance. This approach is novel in that the disturbance forces were observed in reverse through their effects on tracking performance, thus successfully obtaining the disturbance forces of the walker. To ensure the practical finite-time stability of the system, the nonlinear finite-time compensation tracking controller with stochastic configuration networks (SCN) dead-zone estimation was built for the rehabilitative walker. Simulation results and comparative analyses confirmed that the proposed compensation control method effectively restrains dead zone and internal disturbance forces.

19.
Cureus ; 16(6): e62786, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39036179

ABSTRACT

Objectives This study aims to evaluate semicircular canal function using video head impulse test (vHIT) in patients with peripheral vestibular disorders without nystagmus. Methods Patients who underwent vHIT were enrolled in this study, and the proportion of abnormal findings on vHIT in patients without nystagmus was investigated. In addition, the results of vestibular testing were investigated in cases in which both vHIT and caloric testing were performed in patients without nystagmus. Results Forty-six patients (23.4%) of 197 patients who had no abnormal findings on the nystagmus tests, including the gaze nystagmus test, positional nystagmus test, and positioning nystagmus test, showed dysfunction in at least one semicircular canal on vHIT. The most frequent diagnosis was vestibular schwannoma (14/46, 30.4%), and cases with bilateral vestibular dysfunction were also included (12/46, 26.1%). A disorganized pattern of catch-up saccade was observed more frequently in patients with subjective symptoms of dizziness/vertigo compared to those without subjective symptoms. Although the sensitivity of vHIT was low compared to caloric testing, vHIT could detect isolated vertical canal dysfunction not detected by caloric testing. Conclusions vHIT is considered to be a useful test for patients without nystagmus, as vHIT could detect abnormalities in approximately one-quarter of patients without nystagmus. vHIT is considered to be one of the first tests to be performed following nystagmus testing, including the gaze nystagmus test, the positional nystagmus test, and the positioning nystagmus test. On the other hand, there are some cases in which vHIT shows no abnormality while caloric testing shows canal paresis. It is necessary to perform vHIT, bearing in mind that there are abnormalities that cannot be detected by vHIT alone.

20.
Article in English | MEDLINE | ID: mdl-39041598

ABSTRACT

OBJECTIVES: This study examines how older adults' (65 years old plus) daily activities shifted in the years around the coronavirus disease (COVID) pandemic. METHODS: Using data from American Time Use Survey, this study compares activities across the pre-pandemic (2019 to March 2020), early-pandemic (May to December 2020), and pandemic-normal (2021) periods. RESULTS: In the first year of the pandemic, there was less time spent on average on leisure outside the home, traveling, and with nonhousehold members, and more time alone and at home, compared with before the pandemic. Moving beyond averages, sequence and cluster analyses find 5 similar typologies of days across the three periods, characterized by days predominated by (a) housework, (b) leisure at home, (c) TV, (d) a combination of leisure at home and outside with TV, and (e) paid work. Duration of time across various daily activities differed, however, even for the same clusters. For example, in days predominated by indoor leisure, adults spent 405 min in this activity before the pandemic, 432 min during the early-pandemic period, and 549 min during the pandemic-normal period. We also observed changes in the proportion of older adults in each cluster. Across the pre-pandemic and early-pandemic periods, the proportion of days predominated by leisure at home increased (9.9%-17.9%) whereas the proportion belonging to days predominated by housework decreased (45.7%-17.6%). DISCUSSION: COVID-19 shifted the daily life of older adults, and our findings are consistent with selection, optimization, and compensation theory, documenting that older adult adapted across the first 2 years of the pandemic.


Subject(s)
Activities of Daily Living , COVID-19 , Leisure Activities , Humans , COVID-19/epidemiology , Aged , Female , Male , Aged, 80 and over , United States/epidemiology
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