Amplitude Deviation Research Articles

The Diurnal Variation in Mitochondrial Gene in Human Type 2 Diabetic Mesenchymal Stem Cell Grafts.

The application of regenerative therapy through stem cell transplantation has emerged as a promising avenue for the treatment of diabetes mellitus (DM). Transplanted tissue homeostasis is affected by disturbances in the clock genes of stem cells. The aim of this study is to investigate the diurnal variation in mitochondrial genes and function after transplantation of adipose-derived mesenchymal stem cells (T2DM-ADSCs) from type 2 diabetic patients into immunodeficient mice. Diurnal variation in mitochondrial genes was assessed by next-generation sequencing. As a result, the diurnal variation in mitochondrial genes showing troughs at ZT10 and ZT22 was observed in the group transplanted with adipose-derived mesenchymal stem cells derived from healthy individuals (N-ADSC). On the other hand, in the group transplanted with T2DM-ADSCs, diurnal variation indicative of troughs was observed at ZT18, with a large phase and amplitude deviation between the two groups. To evaluate the diurnal variation in mitochondrial function, we quantified mitochondrial DNA copy number using the Human mtDNA Monitoring Primer Set, measured mitochondrial membrane potential using JC-1, and evaluated mitophagy staining. The results showed a diurnal variation in mitochondrial DNA copy number, mitophagy, mitochondrial membrane potential, and NF-kB signaling in the N-ADSC transplant group. In contrast, no diurnal variation was observed in T2DM-ADSC transplants. The diurnal variation in mitochondrial function revealed in this study may be a new marker for the efficiency of T2DM-ADSC transplantation.

Pallidal and motor cortical interactions determine gait initiation dynamics in Parkinson's disease.

Gait initiation is a fundamental human task, requiring one or more anticipatory postural adjustments (APA) prior to stepping. Deviations in amplitude and timing of APAs exist in Parkinson's disease (PD), causing dysfunctional postural control which increases the risk of falls. The motor cortex and basal ganglia have been implicated in the regulation of postural control, however, their dynamics during gait initiation, relationship to APA metrics, and response to pharmacotherapy such as levodopa are unknown. To address these questions, we streamed electrocorticography (ECoG) potentials from the premotor and primary motor cortices, as well as local field potentials (LFPs) from the globus pallidus in five people with PD exhibiting gait and balance dysfunction during a cued gait initiation task. Amplitude and timing of APA were evaluated with force plates and synchronized to the neural data. Subjects performed gait initiation trials under ON and LOW levodopa conditions to assess effects of medication on APA metrics and underlying neural dynamics. All subjects demonstrated pallidal and cortical oscillatory changes during different phases of gait initiation. Grouped analysis revealed that from quiet standing to the first foot step, pallidal beta power showed stepwise decrease and broadband gamma power increases, whereas cortical potentials showed low frequency (theta, alpha, beta) power decrease during gait initiation, regardless of medication state. The pallidum and motor cortices also became increasingly coherent during gait initiation compared to quiet standing prior to APA onset. Using linear mixed models, we found that while pallidal gamma powers are predictive of APA scaling, pallidal-cortical coherence (theta, alpha, beta) and premotor-M1 gamma coherence are predictive of APA timing. Our study is the first detailed characterization of basal-ganglia cortical circuit dynamics during human gait initiation. We identified significant pallidal motor cortical power and coherence changes that underlie the amplitude and timing of APA which appear to be independent of medication states of the study subjects. Our results provide evidence for a model where synchronized premotor and motor cortical activities transiently couple with the globus pallidus to regulate the timing of postural responses, and local pallidal activity regulate the amplitude of postural changes during gait initiation. It suggests that abnormal pallidal outflow and synchronization between the pallidum and motor cortices may be a pathophysiological mechanism underlying disordered postural response in Parkinson's disease.

Middle and Long Latency Cutaneous Reflexes During the Stance Phase of Gait in Individuals with and Without Chronic Ankle Instability

Background/objectives: Lower limb cutaneous reflex amplitudes can modulate across gait, which helps humans adjust rhythmic motor outputs to maintain balance in an ever-changing environment. Preliminary evidence suggests people who suffer from repetitive ankle sprains and residual feelings of giving way demonstrate altered cutaneous reflex patterns in the gastrocnemius. However, before cutaneous reflex assessment can be implemented as a clinical outcome measure, there is a need to substantiate these early findings by measuring reflex amplitudes across longer latency periods and exploring the variability of reflexes within each subject. Methods: Forty-eight subjects with and without chronic ankle instability (CAI) walked on a treadmill at 4 km/h while activity of the lateral gastrocnemius (LG) was measured via surface electromyography. Non-noxious stimulations were elicited randomly to the ipsilateral sural nerve at the mid-stance phase of gait, and reflex amplitudes were calculated offline by comparing muscle activity during unstimulated and stimulated gait cycles. Two primary outcome measures were compared between groups at the middle latency (MLR: 80–120 ms) and late latency (LLR: 120–150 ms) time windows: (1) average reflex amplitudes and (2) standard deviation of reflex amplitudes for each subject across 10 trials. Results: Both groups demonstrated an equal amount of LG inhibition at the MLR and LG facilitation at the LLR. However, subjects with CAI showed significantly higher variability in LLR amplitude across trials than healthy controls. Conclusions: Increased variability of cutaneous reflex amplitudes may relate to symptoms associated with CAI. These findings suggest that reflex variability following sural nerve stimulation could serve as an objective measure to track treatment progress in patients with CAI, offering clinicians a new tool for conducting rehabilitation assessments in a controlled environment.

Assessment of Chromosome Oscillations in Mammalian Cells by Live Cell Imaging.

In metaphase, chromosomes undergo a back-and-forth movement between two spindle poles called chromosome oscillation. This dynamic is necessary to maintain the robustness of chromosome segregation. This chapter describes the materials and methods required to observe chromosome oscillation in mammalian cell lines and calculate the deviation of amplitude (DAP), which is used to quantify the degree of chromosome oscillation.

Central Retinal Thickness Variability as a Predictive Factor for Visual Acuity After Dexamethasone Implant in Retinal Vein Occlusion.

Investigate central retinal thickness (CRT) variability and changes in best-corrected visual acuity (BCVA) after 12 months in patients with retinal vein occlusion (RVO) treated with dexamethasone intravitreal implants. Post hoc analyses of two randomized trials in patients with macular edema associated with branch or central RVO treated with a 0.7-mg dexamethasone implant. Central retinal thickness standard deviation (CRT-SD) and central retinal thickness amplitude (CRT-A) were measures of variability. Analyses included multinomial and simple linear regression. In 400 patients, CRT-SD and CRT-A were significantly associated with central RVO, second dexamethasone implant, and baseline CRT. Baseline BCVA was associated with CRT-A. CRT-SD and CRT-A were significantly correlated with a 12-month change in BCVA (effect sizes of -0.032 and -0.013 letters/µm; P < 0.001). Patients in the highest CRT-SD quartile gained significantly fewer letters (+1.88 letters; 95% CI: -0.46 to 4.23). Greater CRT variability was associated with smaller BCVA improvements in patients with RVO treated with dexamethasone implants. [Ophthalmic Surg Lasers Imaging Retina 2024;55:722-729.].

Floor live load survey and modelling by house VR viewing and public registration information

Reliable live load value is a prerequisite for the safety design of civil structures, and the quantity of samples is the key data foundation for live load modelling. The traditional walk-in survey approach has encountered challenges such as low efficiency, high costs, and potential privacy concerns, resulting in a limited collection of live load samples and a halt in load surveys over the past three to four decades. To address these issues, this paper proposes a new online survey approach for floor live load sampling. The new approach uses a panoramic VR (virtual reality) house viewing system, available and open-access on many real estate trading websites, to collect load amplitude samples. Additionally, it utilizes public information systems, including real estate transactions and national enterprise credit system, to collect live load duration samples. The practical implementation of this novel approach yields a substantial volume of samples, with 1883 and 4676 load amplitude samples, and 121,561 and 46,353 duration samples obtained for office and residential buildings, respectively, constituting the largest live load sample set reported to date. Statistical analysis reveals that design live load values derived from the new samples are higher than the recommended values in the current code, due to a notable increase in the standard deviation of load amplitude and a significant decrease in the load duration. Overall, the proposed approach presents a novel, efficient, and convenient method for live load modelling.

Rayleigh wave-based monitoring of mortar coating and concrete core cracking on prestressed concrete cylinder pipe under external pressure using piezoelectric lead zirconate titanate

Prestressed concrete cylinder pipe (PCCP) is a critical type of pressure pipe widely used in major water conveyance projects worldwide. As essential components of a PCCP, the mortar coating and concrete core are directly linked to its operational safety. This study employed piezoelectric lead zirconate titanate (PZT) devices as transducers to generate excitation vibrations and measure the resulting Rayleigh waves, thereby providing a means to detect cracking in and monitor the health of the mortar coating and concrete core of a prototype 1400 mm inner-diameter PCCP under external pressure. First, a theoretical analysis was conducted to define the propagation laws of Rayleigh waves. Next, a finite element analysis was undertaken to identify the tensile regions of the PCCP mortar coating and concrete core when under external pressure applied along the length of the PCCP and thereby establish the locations for the PZT devices. Experiments were subsequently conducted by incrementally increasing the external pressure load from 0 to 700 kN while monitoring the cracking in the mortar coating and concrete core using sinusoidal excitation signals with frequencies of 5, 10, and 20 kHz. The voltage amplitudes measured at each external pressure load were analysed, confirming the Rayleigh wave propagation laws and revealing that the change in the measured voltage amplitude curve aligned with the experimental observations, thereby validating the proposed measurement method. Finally, the relative percentage deviation of amplitude (RPDA) and relative percentage deviation of energy (RPDE) damage indices were established based on the voltage measurements to further evaluate the damage state of the mortar coating and concrete core. The RPDA measured at an excitation frequency of 20 kHz was best for detecting cracks in the PCCP mortar coating, whereas the RPDA and RPDE measured at excitation frequencies of 20 and 10 kHz, respectively, were best for monitoring concrete core cracking.

Differentiating Postural and Kinetic Tremor Responses to Deep Brain Stimulation in Essential Tremor.

While deep brain stimulation (DBS) targeting the ventral intermediate nucleus (VIM) of thalamus or posterior subthalamic area (PSA) can suppress forms of action tremor in people with Essential Tremor, previous studies have suggested postural tremor may respond more robustly than kinetic tremor to DBS. In this study, we aimed to more precisely quantify the (1) onset/offset dynamics and (2) steady-state effects of VIM/PSA-DBS on postural and kinetic tremor. Tremor data from wireless inertial measurement units were collected from 11 participants with ET (20 unilaterally assessed DBS leads). Three postural hold tasks and one kinetic task were performed with stimulation turned off, in 2-min intervals after enabling unilateral DBS at the clinician-optimized DBS setting (15 min), and in 2-min intervals following cessation of DBS (5 min). At baseline, kinetic tremor had significantly higher amplitudes, standard deviation, and frequency than postural tremor (P < 0.001). DBS had a more robust acute effect on postural tremors (54% decrease, P < 0.001), with near immediate tremor suppression in amplitude and standard deviation, but had non-significant improvement of kinetic tremor on the population-level across the wash-in period (34% decrease). Tremor response was not equivalent between wash-in and wash-out timepoints and involved substantial individual variability including task-specific rebound or long wash-out effects. Programming strategies for VIM/PSA-DBS should consider the individual temporal and effect size variability in postural versus kinetic tremor improvement. Improved targeting and programming strategies around VIM and PSA may be necessary to equivalently suppress both postural and kinetic tremors.

A universal method for seizure onset zone localization in focal epilepsy using standard deviation of spike amplitude

BackgroundPrecisely localizing the seizure onset zone (SOZ) is critical for focal epilepsy surgery. Existing methods mainly focus on high-frequency activities in stereo-electroencephalography, but often fail when seizures are not driven by high-frequency activities. Recognized as biomarkers of epileptic seizures, ictal spikes in SOZ induce epileptiform discharges in other brain regions. Based on this understanding, we aim to develop a universal algorithm to localize SOZ and investigate how ictal spikes within the SOZ induce seizures. MethodsWe proposed a novel metric called standard deviation of spike amplitude (SDSA) and utilized channel-averaged SDSA to describe seizure processes and detect seizures. By integrating SDSA values in specific intervals, the score for each channel located within SOZ was calculated. Channels with high SOZ scores were clustered as SOZ. The localization accuracy was asserted using area under the receiver operating characteristic (ROC) curve. Further, we analyzed early ictal signals from SOZ channels and investigated factors influencing their duration to reveal the seizure inducing conditions. ResultsWe analyzed data from 15 patients with focal epilepsy. The channel-averaged SDSA successfully detected all 28 seizures without false alarms. Using SDSA integration, we achieved precise SOZ localization with an average area under ROC curve (AUC) of 0.96, significantly outperforming previous methods based on high-frequency activities. Further, we discovered that energy of ictal spikes in SOZ was concentrated at a specific frequency distributed in [6, 12 Hz]. Additionally, we found that the higher the energy per second in this frequency band, the faster ictal spikes could induce seizures. ConclusionThe SDSA metric offered precise SOZ localization with robustness and low computational cost, making it suitable for clinical practice. By studying the propagation patterns of ictal spikes between the SOZ and non-SOZ, we suggest that ictal spikes from SOZ need to accumulate energy at a specific central frequency to induce epileptic spikes in non-SOZ, which may have significant implications for understanding the seizure onset pattern.

A Computational Model of the Electrically or Acoustically Evoked Compound Action Potential in Cochlear Implant Users With Residual Hearing.

In cochlear implant users with residual acoustic hearing, compound action potentials (CAPs) can be evoked by acoustic (aCAP) or electric (eCAP) stimulation and recorded through the electrodes of the implant. We propose a novel computational model to simulate aCAPs and eCAPs in humans, considering the interaction between combined electric-acoustic stimulation that occurs in the auditory nerve. The model consists of three components: a 3D finite element method model of an implanted cochlea, a phenomenological single-neuron spiking model for electric-acoustic stimulation, and a physiological multi-compartment neuron model to simulate the individual nerve fiber contributions to the CAP. The CAP morphologies closely resembled those known from humans. The spread of excitation derived from eCAPs by varying the recording electrode along the cochlear implant electrode array was consistent with published human data. The predicted CAP amplitude growth functions largely resembled human data, with deviations in absolute CAP amplitudes for acoustic stimulation. The model reproduced the suppression of eCAPs by simultaneously presented acoustic tone bursts for different masker frequencies and probe stimulation electrodes. The proposed model can simulate CAP responses to electric, acoustic, or combined electric-acoustic stimulation. It considers the dependence on stimulation and recording sites in the cochlea, as well as the interaction between electric and acoustic stimulation in the auditory nerve. The model enhances comprehension of CAPs and peripheral electric-acoustic interaction. It can be used in the future to investigate objective methods, such as hearing threshold assessment or estimation of neural health through aCAPs or eCAPs.

Classifying physical activity levels using Mean Amplitude Deviation in adults using a chest worn accelerometer: validation of the Vivalink ECG Patch

BackgroundThe development of readily available wearable accelerometers has enabled clinicians to objectively monitor physical activity (PA) remotely in the community, a superior alternative to patient self-reporting measures. Critical to the value of these monitors is the ability to reliably detect when patients are undergoing ambulatory activity. Previous studies have highlighted the strength of using mean amplitude deviation (MAD) as a universal measure for analysing raw accelerometery data and defining cut-points between sedentary and ambulatory activities. Currently however there is little evidence surrounding the use of chest-worn accelerometers which can provide simultaneous monitoring of other physiological parameters such as heart rate (HR), RR intervals, and Respiratory Rate alongside accelerometery data. We aimed to calibrate the accelerometery function within the VivaLink ECG patch to determine the cut-point MAD value for differentiating sedentary and ambulatory activities.MethodsWe recruited healthy volunteers to undergo a randomised series of 9 activities that simulate typical free-living behaviours, while wearing a VivaLink ECG Patch (Campbell, California). MAD values were applied to a Generalised Linear Mixed Model to determine cut-points between sedentary and ambulatory activities. We constructed a Receiver Operating Characteristic (ROC) curve to analyse the sensitivity and specificity of the cut-off MAD value.ResultsEighteen healthy adults volunteered to the study and mean MAD values were collected for each activity. The optimal MAD cut-point between sedentary and ambulatory activities was 47.73mG. ROC curve analysis revealed an area under the curve of 0.99 (p < 0.001) for this value with a sensitivity and specificity of 98% and 100% respectively.ConclusionIn conclusion, the MAD cut-point determined in our study is very effective at categorising sedentary and ambulatory activities among healthy adults and may be of use in monitoring PA in the community with minimal burden. It will also be useful for future studies aiming to simultaneously monitor PA with other physiological parameters via chest worn accelerometers.

Experimental Evaluation of the Possibility of Through Defects Detection in Thermally Expanded Graphite Workpieces by Acoustic Method

The paper presents the results of evaluating the possibility of detecting defects (e.g., through holes) in workpieces made of thermally expanded graphite used as sealing materials using a non-contact air-coupled acoustic inspection system. The deviation of the acoustic signal amplitude when it passes through a sample of thermally expanded graphite in defective and defect-free regions is used as an informative parameter. The obtained dependences of the change in the amplitude of the passed signal through the sample on the size of the artificial through hole, density and thickness of the object showed a significant influence of these parameters on the detectability of the defect, which should be taken into account in the development of inspection technologies and in the process of its implementation. The change in the amplitude of the signal passed through the object directly depends on the increase in the parameters of the sample (density, thickness) and the size of the through hole, which increases the sensitivity of acoustic control and detectability of defects.On the basis of the obtained dependences the criteria for rejection of workpieces can be developed at the stage of production or immediately before manufacturing of their products. The influence of defect positioning relative to the acoustic axis of the transmitter-receiver system is shown, which leads to a decrease in the informative parameter, and consequently to a decrease in sensitivity. This dependence is characteristic for all thicknesses and densities of objects, as well as for all sizes of artificial through holes when control is carried out immediately after defect formation. When acoustic inspection is carried out some time after the defect formation, the maximum of this dependence may shift due to the shift of the amount of substance to fill the defect cavity, which is confirmed by microscopy. The obtained results can be used in the development of workpieces acoustic control parameters.

Study on radial deviation amplitude of out-of-roundness of resilient wheel installed on a subway vehicle based on vehicle operation safety regulation

Following the extensive use of resilient wheels on trams, several subways in China have also started to pre-launch testing of resilient wheels, while it remains to be at a beginning stage, the wheel maintenance during its long-term service has become a great concern by subway operators and wheel suppliers. An effort is presented in this paper, trying to provide an invaluable reference. Firstly, a metro vehicle-track dynamic system model fitted with the resilient wheels is built. Then, based on the operation safety index and current wheel re-profiling regulations, the influence of wheel axial and radial stiffness combination on radial deviation maximum of resilient wheel polygonization wear is analyzed. The equivalent stiffnesses of the resilient wheel involve the radial stiffness within 600 kN/mm and the axial stiffness within 100 kN/mm. The amplitude of polygonization below the 10th order on the resilient wheel is within 1 mm. A contour chart is drawn to present how the wheel weight reduction rate varies with wheel polygonization order and amplitude under different combinations of resilient wheel equivalent axial and radial stiffnesses. A series of contours is abstracted to query the amplitude limits of the polygonization of different orders on resilient wheels with different equivalent stiffnesses.

Variability of cortico-cortical evoked potentials in the epileptogenic zone is related to seizure occurrence.

Cortico-cortical evoked potentials (CCEPs) were described as reproducible during trains of single-pulse electrical stimulations (SPES). Still, few studies described a variability of CCEPs that was higher within the epileptogenic zone (EZ). This study aimed at characterizing the relationship of CCEP variability with the occurrence of interictal/ictal epileptiform discharges at the temporal vicinity of the stimulation, but not during the stimulation, by effective connectivity modifications. We retrospectively included 20 patients who underwent SPES during their stereo-electroencephalography (SEEG). We analyzed the variability of CCEPs by using the post-stimulation time course of intertrial standard deviation (amplitude) and the timing of peak amplitude signal of CCEP epochs (latency). Values were corrected for the Euclidian distance between stimulating/recording electrodes. Receiver operating characteristics curves were used to assess the relationship with the EZ. The link between CCEP variability and interictal discharges occurrence, seizure frequency prior to the SEEG recording, and number of seizures during SEEG recording was assessed with Spearman's correlations. A relationship was demonstrated between the EZ and both the distance-corrected latency variation (area under the curve (AUC): 0.73-0.74) and the distance-corrected amplitude variation (AUC: 0.71-0.72) and both were related with the occurrence of seizures. Seizures before/during SEEG impact the dynamics of effective connectivity within the epileptogenic network by reducing the variability of CCEP latency/amplitude when the seizure frequency increases. It suggests a strengthening of the epileptogenic network with the occurrence of many seizures. These findings stress the importance of early epilepsy surgery at a time when the network organization has not yet been complete.

Fault location method for new distribution networks based on waveform matching of time–frequency travelling waves

AbstractSome existing fault location methods for distribution networks rely too much on the local wave head information of the time or frequency domain signals, making it difficult to adapt to the increasingly complex structure and operating conditions of the distribution network after the new energy access. For improvement, the travelling wave (TW) time and frequency ranges that can effectively avoid waveform distortion caused by new energy access are analysed. The one‐to‐one matching relationship between the TW waveforms in these ranges and the fault positions is revealed. A fault TW time–frequency matrix with specific time and frequency windows is constructed, and a new distribution network fault location method is proposed based on the matching technique of waveform features, which realises the accurate fault location by exploring the proportionality between the cumulative trend of the matrix energy amplitude deviation and the fault point position. Simulation test results show that the proposed method is not affected by the complex structure of distribution networks such as new energy access and overhead‐cable line mixing on fault location and flexibly transforms the fault location problem into a time–frequency TW waveform matching problem, which improves the accuracy and robustness of the fault location for new distribution networks to a degree.

A novel computational signal processing framework towards multimodal vital signs extraction using neck-worn wearable devices

Pulse rate (PR) and respiratory rate (RR) are two of the most important vital signs. Monitoring them would benefit from easy-to-use technologies. Hence, wearable devices would, in principle, be ideal candidates for such systems. The neck, although highly susceptible to artifacts, presents an attractive location for a diverse pool of physiological biomarkers monitoring purposes such as airflow sensing in a non-obstructive manner. This paper presents a methodology for PR and RR estimation using photoplethysmography (PPG) and accelerometry (Acc) sensors placed on the neck. Neck PPG and Acc signals were recorded from 22 healthy participants for RR estimation, where the resting subjects performed guided breathing following a visual metronome. Neck PPG signals were obtained from 16 healthy participants who breathed through an altitude generator machine in order to acquire a wider range of PR readings while at rest. The proposed methodology was able to provide rate estimates via a combination of recursive FFT-based dominance scoring coupled with an exponentially weighted moving average (EWMA)-driven aggregation scheme. The recursion aimed at bypassing sudden intra-window amplitude deviations caused by momentary artifacts, while the EWMA-based aggregation was utilized for handling inter-window artifact-induced deviations. To further improve estimation stability and confidence, estimates were calculated in the form of rate bands taking into account the relevant clinically acceptable error margins, and results when considering rate values and rate bands are presented and discussed. The framework was able to achieve an overall pulse rate value accuracy of 93.67±7.64\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$93.67\\pm 7.64$$\\end{document}% within the clinically acceptable ± 5 BPM with reference to the gold-standard reference devices while providing an overall respiratory rate value accuracy within the clinically appropriate ± 3 BrPM of 94.94±3.56\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$94.94\\pm 3.56$$\\end{document}% with reference to the guiding visual metronome, and 88.4±7.63\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$88.4\\pm 7.63$$\\end{document}% with respect to the gold-standard reference device. The proposed methodology achieves acceptable PR and RR estimation capabilities, even when signals are acquired from an unusual location such as the neck. This work introduces novel ideas that can lead to the development of medical device outputs for PR and RR monitoring, especially capitalizing on the advantages of the neck as a multi-modal physiological monitoring location.

A comparative analysis of 24-hour movement behaviors features using different accelerometer metrics in adults: Implications for guideline compliance and associations with cardiometabolic health.

Movement behavior features such as time use estimates, average acceleration and intensity gradient are crucial in understanding associations with cardiometabolic health. The aim of this study was to 1) compare movement behavior features processed by commonly used accelerometer metrics among adults (i.e. Euclidian Norm Minus One (ENMO), Mean Amplitude Deviation (MAD) and counts per minute (CPM)), 2) investigate the impact of accelerometer metrics on compliance with movement behavior guidelines, and 3) explore potential variations in the association between movement behavior features and cardiometabolic variables depending on the chosen metric. This cross-sectional study collected movement behavior features (Actigraph GT3X+) and cardiometabolic variables. Accelerometer data were analyzed by four metrics, i.e. ENMO, MAD, and CPM vertical axis and CPM vector magnitude (GGIR). Intraclass correlations and Bland‒Altman plots identified metric differences for time use in single movement behaviors (physical activity, sedentary behavior), average acceleration and intensity gradient. Regression models across the four metrics were used to explore differences in 24-hour movement behaviors (24h-MBs; compositional variable) as for exploration of associations with cardiometabolic variables. Movement behavior data from 213 Belgian adults (mean age 45.8±10.8 years, 68.5% female) differed according to the metric used, with ENMO representing the most sedentary movement behavior profile and CPM vector magnitude representing the most active profile. Compliance rates for meeting integrated 24h-MBs guidelines varied from 0-25% depending on the metric used. Furthermore, the strength and direction of associations between movement behavior features and cardiometabolic variables (body mass index, waist circumference, fat% and HbA1c) differed by the choice of metric. The metric used during data processing markedly influenced cut-point dependent time use estimates and cut-point independent average acceleration and intensity gradient, impacting guideline compliance and associations with cardiometabolic variables. Consideration is necessary when comparing findings from accelerometry studies to inform public health guidelines.

Prediction of glaucoma progression by 24-h contact lens sensor profile in patients with normal-tension glaucoma

A single-center prospective cohort study was conducted to investigate whether intraocular pressure (IOP)-related 24-h contact lens sensor (CLS) profile parameters can help predict glaucoma progression in patients with normal-tension glaucoma (NTG). CLS measurements (Triggerfish; SENSIMED, Etagnières, Switzerland) at baseline without medication were performed for 24 h in one eye, following diurnal IOP measurements using Goldmann applanation tonometry at 3-h intervals. Glaucoma progression during the follow-up period of ≥ 2 years was determined based on the Guided Progression Analysis of Humphrey visual fields and/or structural progression using fundus photographs. Among 79 patients (mean values: follow-up periods, 48.1 months; age, 51.5 years; baseline IOP, 14.0 mmHg; mean deviation, − 6.04 dB), 23 showed glaucoma progression. A smaller standard deviation of nocturnal ocular pulse amplitude in the CLS profile, a larger range of diurnal IOP at baseline, and the presence of optic disc hemorrhage (DH) during the study period were significant risk factors for glaucoma progression in the multivariate Cox proportional hazards model (hazard ratio, 0.30/mVeq, 1.23/mmHg, and 4.37/presence of DH; P = 0.016, 0.017, and 0.001, respectively). CLS measurements may be useful for assessing the risk of future glaucoma progression in patients with NTG, providing supplementary information to routine IOP measurements.

Acute Effect of Imeglimin Add-on Therapy on 24-h Glucose Profile and Glycemic Variability in Patients with Type 2 Diabetes Receiving Metformin

Introduction: Imeglimin is a novel antidiabetic drug with insulinotropic and insulin-sensitizing effects that targets mitochondrial bioenergetics. We investigated acute effects of add-on therapy with imeglimin to preceding metformin on the 24-h glucose profile and glycemic variability assessed by continuous glucose monitoring (CGM) in patients with type 2 diabetes. Methods: We studied 30 outpatients with type 2 diabetes inadequately controlled with metformin. CGM was used for 14 days straight during the research period. Imeglimin 2,000 mg/day was started on day 7 after initiating CGM. Several CGM parameters were compared between days 4–6 (prior to imeglimin treatment) and 11–13 (following the initiation of imeglimin treatment). Results: After treatment with imeglimin, 24-h mean glucose was acutely decreased from 161.6 ± 48.0 mg/dL to 138.9 ± 32.2 mg/dL (p < 0.0001), while time in range (i.e., at a glucose level of 70–180 mg/dL) was significantly increased from 69.9 ± 23.9% to 80.6 ± 21.0% (p < 0.0001). Addition of imeglimin to metformin significantly decreased the standard deviation (SD) of 24-h glucose and mean amplitude of glycemic excursions, 2 indexes of glycemic variability. Baseline serum high-density lipoprotein (HDL) cholesterol was negatively correlated with changes in mean 24-h glucose (r = −0.3859, p = 0.0352) and those in SD (r = −0.4015, p = 0.0309). Conclusions: Imeglimin add-on therapy to metformin acutely lowered 24-h glucose levels and improved glycemic variability in patients with type 2 diabetes on metformin. A higher serum HDL cholesterol at baseline was associated with a better response to acute effects of imeglimin on 24-h glucose levels and glycemic variability.

A distributed coordinated control strategy for isolated AC microgrids based on consensus algorithm considering communication delay

AbstractIn the multi‐paralleled converter microgrid system, the traditional hierarchical control strategy can eliminate the bus voltage amplitude and frequency deviation from the rated value. However, isolated AC microgrids may face extreme scenarios such as communication delays and interruptions in data transmission due to the use of low‐bandwidth communication (LBC) lines. Additionally, the inconsistent line impedance of each distributed generation (DG) unit may result in the inaccurate division of reactive power in multi‐paralleled converter systems, thus affecting system stability. To address these issues, this paper presents a distributed coordinated control strategy for isolated AC microgrids based on the consensus algorithm. The proposed strategy first replaces LBC lines with a filter to alleviate the effects of communication delays. A small‐signal model is established in its state space, and stability of the microgrid system under the proposed control strategy is verified through eigenvalue analysis. Furthermore, based on the above theoretical analysis, a consensus algorithm is introduced, and a distributed control strategy for isolated AC microgrids based on the consensus algorithm is proposed to solve the issue of inaccurate equalization of the system's reactive power. Finally, factors that influence the dynamic convergence performance of the consensus algorithm are analyzed through simulation in PLECS software. Also, the maximum tolerable communication delays of the microgrid system under different communication topologies are also compared, and the system's robustness is evaluated under the condition of sudden communication interruption in a DG unit and sudden weather variation. These analyses confirmed the robustness of the proposed strategy against communication delays, output power fluctuation, and communication interruptions.