Single Control Research Articles

Quantifying Morphological Changes in Middle Trapezius With Ultrasonography and Histogram Matching for Participants With and Without Facioscapulohumeral Dystrophy

Objective: Echogenicity is a biomarker in facioscapulohumeral muscular dystrophy (FSHD). Currently, it is not possible to compare echogenicity values, derived using quantified muscle sonography capture, based on different equipment instrumentation settings. Image normalization, using histogram matching, could address this limitation. The aim of this study was to investigate the sensitivity of histogram matching, with trapezius muscle echogenicity values, in participants with and without FSHD. Materials and Methods: Sensitivity analysis of a single measurement timepoint case control study of participants with FSHD, using age- and gender-matched controls. Correlations between trapezius muscle echogenicity, muscle thickness, and shoulder range of movements were also completed. Results: Data were collected for 14 participants, seven with FSHD and seven controls. The cohort had a mean age of 41.6 years. The FSHD group echogenicity values (118.2) were higher than controls (42.3), respectively, as well as statistically significant ( p = .002). An overall variance of 6.2 (range = −2.9 to 15.4) was identified between the reference images. Echogenicity explained 81% of the variance in muscle thickness and 74% of the variance in range of movement muscle thickness was explained by 61% of the variance for range of movement. Conclusion: Histogram matching for comparison of echogenicity was required. Different reference images affect echogenicity values, but the variability was less than between group differences. Further longitudinal evaluation based on a larger sample of participants is needed.

MYH6 Variants Are Associated with Atrial Dysfunction in Neonates with Hypoplastic Left Heart Syndrome

Background: MYH6 variants are the most well-known genetic risk factor (10%) for hypoplastic left heart syndrome (HLHS) and are associated with decreased cardiac transplant-free survival. MYH6 encodes for α-myosin heavy chain (α-MHC), a contractile protein expressed in the neonatal atria. We therefore assessed atrial function in HLHS patients with MYH6 variants. Methods: We performed a retrospective, blinded assessment of pre-stage I atrial function using 2D speckle-tracking echocardiography (2D-STE). Variant carriers were control-matched based on AV valve anatomy, sex, and birth year. Studies were obtained postnatally from awake patients prior to surgical intervention. Right atrial (RA) and right ventricular (RV) strain and strain rate (SR) were measured from the apical four-chamber view. Results: A total of 19 HLHS patients with MYH6 variants had echocardiograms available; 18 were matched to two controls each, and one had a single control. RA active strain (ASct) was decreased in variant carriers (−1.41%, IQR −2.13, −0.25) vs. controls (−3.53%, IQR −5.53, −1.28; p = 0.008). No significant differences were identified in RV strain between the groups. RA reservoir strain (ASr) and conduit strain (AScd) positively correlated with heart rate (HR) in MYH6 variant carriers only (ASr R = 0.499, p = 0.029; AScd R = 0.469, p = 0.043). RV global longitudinal strain (GLS) as well as RV systolic strain (VSs) and strain rate (VSRs) correlated with HR in controls only (GLS R = 0.325, p = 0.050; VSs R = 0.419, p = 0.010; VSRs R = 0.410, p = 0.012). Conclusions: We identified functional consequences associated with MYH6 variants, a known risk factor for poor outcomes in HLHS. MYH6 variant carriers exhibit impaired RA contractility despite there being no differences in RV function between variant carriers and controls. MYH6 variants are also associated with an ineffective RA reservoir and conduit function at high heart rates, despite preserved RV diastolic function. RA dysfunction and reduced atrial “kick” may therefore be a significant contributor to RV failure and worse clinical outcomes in HLHS patients with MYH6 variants.

Repeated human cranial bone-derived mesenchymal stem cell transplantation improved electrophysiological recovery in a spinal cord injury rat model

Mesenchymal stem cell (MSC)-based therapy has been applied in several clinical trials of spinal cord injury (SCI). We have successfully established MSCs from human cranial bone and developed a longitudinal neuromonitoring technique for rodents. In addition to single transplantation, the potential of multiple transplantations has been suggested as a new therapeutic strategy. However, there are no reports on the electrophysiological effects of multiple MSC transplantations in SCI using transcranial electrical stimulation motor-evoked potentials (tcMEPs). Here, we aimed to elucidate the efficacy and mechanism of action of multiple MSC transplantations using tcMEPs. After establishing a weight-drop-induced SCI rat model, we performed repeated intravenous transplantation of human cranial bone-derived MSCs (hcMSCs) on days 1 and 3 post-SCI. Motor function and tcMEP recovery were evaluated 6 weeks post-transplantation. Tissue repair post-SCI was assessed using immunostaining for myelin and neurons in the injured posterior cord. Repeated hcMSC transplantation significantly improved motor function and electrophysiological recovery compared to single transplantation and control treatment. Repeated hcMSC transplantation promoted electrophysiological functional recovery by exerting a protective effect on the functional structure of pyramidal tract axons. Thus, acute-phase repeated transplantation could be a novel and effective therapeutic strategy for the clinical application of MSCs in SCI.

Chairperson Gender, Policy Compliance and ESG Performance of Family Firms

Compared to other types of companies, family businesses tend to be more dominated by the traditional notion of familialism, believing that women should be more responsible for handling family affairs rather than being involved in business operations and decision-making. Yet there is still a controversy about whether female chairpersonship is more favorable to enterprise development than male chairpersonship. Driven by the globalization process and sustainable development strategies, ESG has become an important indicator for evaluating corporate sustainability and social responsibility. This paper empirically investigates the effect and mechanism of the gender of the chairperson on the ESG performance of family firms by using A-share family firms in China from 2009 to 2022 as the research sample. The results show that female chairpersonship significantly enhances the ESG performance of family firms, and this facilitating effect mainly focuses on the social and governance dimensions, and policy compliance is an important reason why female chairpersonship promotes the ESG performance of family firms. The study also finds that female chairpersons contribute more to family firms’ ESG performance in family firms whose chairpersons are from outside the family, those are indirectly founded, those with a high degree of ownership and control rights disparity, and those with single actual controller. This paper provides a framework for the study of the gender of chairpersons on the ESG performance of family firms, and also provides useful references for the professional equality between males and females and the selection of chairpersons in the real economy.

PID control for the water-air hybrid aquatic-aerial vehicle’s exit based on simulated annealing genetic algorithm optimization

Abstract A hybrid aquatic-aerial vehicle is a special equipment with the ability to perform amphibious operations in water and air, and its control accuracy and stability during the water outflow process are crucial for ensuring the safety and operational efficiency of the vehicle. This article first constructs the kinematic and dynamic models of the hybrid aquatic-aerial vehicle and designs the basic control strategy based on a PID controller. Given the limitations of a single PID control strategy in specific contexts, this study proposes a PID controller based on genetic algorithm optimization and introduces a simulated annealing algorithm in the optimization process of the genetic algorithm to make the adjustment of controller parameters more precise and efficient. Through simulation verification, it was found that the optimized PID controller improved the performance of the aircraft during the outflow stage, indicating that this optimization control strategy has a positive impact on improving the operational performance of the aircraft.

Modeling and control of dynamical biomechanical arm systems with elastic joints sensitive to the effect of an external load

In this study, a biomechanical model mimicking the human hand-arm system under heavy disk excitation is developed to define the stability threshold between the preload vibration and the stress of the human hand-arm system. The fully electromechanical system, consisting of a DC motor, a transmission system, and three discrete masses representing the upper arm, forearm, and hand lifting a heavy disk, is connected by shock absorbers and various springs. The challenge of mimicking the angular activity of the elbow joint in torsion and flexion was also included to assess its contribution to system stability and to study the absorption of mechanical energy in the human hand-arm system. Finally, the movements of the model were described by a differential matrix equation, and its analysis facilitates the understanding of the threshold of the chaotic behaviors observed in an oscillating arms system. Specifically, it explores how the motion of a DC motor can be regulated using a single controller parameter within the context of a multi-degree-of-freedom human hand-arm system. The study uses numerical integrations to analyze system behaviors, with an emphasis on the use of frequency spectra, Poincaré maps, and bifurcation diagrams for visualization and interpretation. The results indicate that the system exhibits chaotic behavior when subjected to certain conditions, particularly when the mass load exceeds 35 kg. Imposing motion on the mass block further intensifies the chaos, leading to manifestations such as strong oscillations and frequency-synchronization effects. These characteristics, exhibited by the idealized model, which imitates the human body through a mechanical model and computation of the motions of the body, play a vital role in various fields of ergonomics and sports biomechanics. Understanding the dynamic behaviors of such systems, especially in response to varying conditions, has significant implications for engineering applications.

Seismic mitigation of porcelain cylindrical electrical equipment using synergistic concept with base isolation and tuned mass damper

Porcelain cylindrical electrical equipment (PCEEs), such as potential and current transformers, are critical components of electrical substations and essential to power supply networks. Nevertheless, previous strong earthquakes have rendered high vulnerability and poor performance of PCEE during seismic occurrences. To improve seismic performance of PCEE and alleviate adverse seismic impacts, an innovative synergistic mitigation method based on base isolation (BI) and tuned mass damper (TMD) was proposed and subsequently employed to PCEE. Combining BI with TMD allows for a greater utilization of each technology’s capabilities while also circumventing some of the limits of each. While TMD effectiveness is sensitive to input ground motion frequencies, BI could act as a filter to tune input frequency and help TMD fulfill better damping effectiveness. TMD could in return help BI achieve better stability under long-period dominant or pulse-like ground motions. The BI-TMD effectiveness and robustness were investigated using finite element modeling and nonlinear time history analysis. A comprehensive parametric study that considers variable PCEE frequencies, BI periods, TMD mass ratios, and TMD control frequencies was conducted. Results show that the proposed BI-TMD method can significantly enhance the effectiveness and robustness beyond BI single control in mitigating seismic responses of PCEE.

Preparation and excellent mechanical properties of nanocrystalline GW103K Mg alloy by HDDR technology

Grain size of GW103K Mg alloy powder were markedly refined to about 45 nm from 20 μm by an optimized hydrogenation-disproportionation-desorption-recombination (HDDR) process. By changing temperature, hydrogen pressure and time, the optimum hydrogenation conditions are explored by orthogonal design. Then the complete dehydrogenation process was determined by using single factor control variables. Furtherly, the HDDRed powder was spark plasma sintering (SPS) sintered and hot extruded to prepare GW103K alloy bulk. XRD, OM, scanning electron microscopy (SEM), and transmission electron microscope (TEM) were used to analyze the phase transformation and microstructure evolution, based on which the grain refining mechanism during the HDDR were discussed. The optimum HDDR parameters for preparing nanocrystalline Mg alloy powders are hydriding at 550 °C under 5 MPa hydrogen pressure for 24 h and dehydriding at 550 °C for 8 h in vacuum. The nanocrystalline GW103 alloy presents a notable dimensional stability and the grain size of the alloy bulk is 43 nm after SPS and hot extrusion. As a result, the nanocrystalline GW103K specimens exhibit excellent mechanical properties compared to the coarse-grained counterparts. Especially, the nanocrystalline GW103K alloy has a tensile elongation of 21.1% which is much more than those of the as-cast and as-extrusion alloys.

Direct Multi‐Thread Adaptive Control With Attracting Manifold Design

ABSTRACTThis article presents a novel multi‐thread attracting manifold (MTAM) adaptive control scheme. The novel contribution of this new controller lies in how the attracting manifold design method is spread across multiple estimates of the truth while simultaneously weighting between said individual estimates to arrive at an adaptive composite estimate which outperforms single thread adaptive controllers. A notable benefit of this new formulation is that it allows for both the weighting of multiple threads and monotonic decrease of parameter error to aid the performance of transient error dynamics, without arbitrarily increasing adaptation gains. The benefits of the proposed controller over existing adaptive control schemes are analyzed through two aerospace flight control applications from the literature.

Effectiveness of recombinant follicle-stimulating hormone treatment in patients with oligo-asthenospermia at different levels of DNA fragmentation index: A phase II clinical trial

Abstract Objective This study aimed to perform an evaluation of changes in spermogram parameters after follicle-stimulating hormone (FSH) therapy in infertile males having oligo-asthenospermia at different levels of DNA fragmentation index (DFI). Materials and methods Infertile men with oligo-asthenospermia, no underlying urogenital disease (such as varicocele), and medically fertile partners were enrolled over 1 year. Semen parameters, FSH, luteinizing hormone, and testosterone levels were determined; also, a Sperm DNA Fragmentation Assay Kit (Hamun Teb Pishro, Tehran, Iran) was used for determining sperm DFI at baseline .Participants were categorized into three groups based on DFI: DFI <15% (group 1), DFI of 15%–30% (group 2), and DFI >30% (group 3). All participants received subcutaneous recombinant FSH (150 mg every other day) for 6 months. Sperm specimens were tested 6 months after intervention (a single sperm control test). Results Sixty males whose average age was 28.4 years were enrolled. Only group 3 (poor fertility) exhibited a significant rise in sperm concentration (p = 0.001) and motility (p < 0.05) after FSH treatment. Group 1 (DFI <30 fertility) and group 2 (DFI of 15%–30%) showed increased mean sperm concentration and motility postintervention, although these alterations were not significantly different. Follicle-stimulating hormone levels increased significantly in all three groups after FSH administration. Serum luteinizing hormone and testosterone levels were not significantly increased in any of the groups. Conclusions FSH treatment improves sperm concentration and motility in men with oligo-asthenospermia, with significant improvements observed in men with DFI >30%. DNA fragmentation index can be a predictive indicator of response to FSH treatment in such patients.

Reverse Selection Designs for Accommodating Multiple Control Arms.

Evaluating a novel treatment in a randomized controlled trial requires comparison against existing therapies. If several existing therapies of similar benefit exist, the identification of a single control regimen may be difficult. For this situation, we propose a reverse selection design which, in its simplest form, includes a single experimental treatment arm and two control arms. Rather than carrying both control arms through the entire trial, the control arms are compared at an early interim analysis, ideally while accrual is ongoing. At this time, the worst-performing control arm is dropped and randomization continues to the remaining arms. At the end of the study, we compare the treatment to the remaining control arm. When no head-to-head comparison of the extant therapies is available or feasible, this design requires a smaller sample size than a traditional three-arm design or two sequential trials in which the extant therapies are compared and the better treatment is used in a subsequent trial as the control arm. This is because the final comparison is only between two arms and because the early interim analysis occurs prior to the end of accrual - yet with enough information such that any substantially better control arm will be selected. We evaluate the operating characteristics of a reverse selection design via simulation and show that it reduces the required sample size needed to compare the treatment against the best control, controls type I error, and likely selects the right control arm to use in the final analysis.

Renewable Energy System Optimization: Mppt Inverter Integration, Energy Storage Systems, And Its Impact on Sustainability and Efficiency Use Of Energy

Abstract: This study endeavors to enhance the utilization of solar panel energy by employing MPPT inverters and integrating energy storage systems. It will be conducted at the Renewable Energy Laboratory, Institute of Technology Sampling, spanning one academic year. Following an experimental research format with a single control group, measurements will be taken pre and post integration of MPPT inverters and energy storage systems to assess energy efficiency and supply stability. Primary data will be gathered from direct measurements of solar panels with integrated MPPT inverters and energy storage systems, encompassing energy production, supply fluctuations, and system stability. Data collection methods include direct measurements with state-of-the-art energy measurement equipment and interviews with renewable energy experts and technicians. Control of variables such as weather conditions and energy consumption will ensure information validity, while external validity will be bolstered by comparing findings with existing literature. Statistical analysis using advanced software will identify significant differences pre and post integration. Additionally, qualitative observations will be conducted to evaluate system stability and the impact of optimization on the sustainability and efficiency of renewable energy utilization.

Optimal and simultaneous synthesis of fractional order QFT controllers and prefilters for non-minimum phase hydro power systems

Abstract Ideally, the operating frequency of the power units, working in parallel, must not deviate from its nominal value. However, due to the dynamic nature of the load, operating frequency varies throughout the day; thus, the control of governors in the prime movers is essential to balance out the demand, and prevent any frequency deviation. To address this, present study investigates the design of optimal and robust quantitative feedback theory based (QFT) controllers and pre-filters for single area load frequency control of hydro power systems. Hydropower system model considered in the present study features a right-hand side zero, thus exhibiting non-minimum phase; these characteristics make the control more challenging. Also, the work investigates the optimal design of the QFT controllers and prefilters simultaneously by automating the loop shaping procedure, which else follows a sequential manual process on Nichols charts. The proposed automation also empowers the control designer to predefine the controller structure. In the present work the design of fractional order QFT controllers and pre-filters is considered. The study also compares the proposed work with the methods proposed in the existing literature as well as the optimal controllers obtained using the time domain indices. The obtained results establishes that the developed fractional QFT controller offers good tracking, stability, and robustness to disturbances when compared to existing approaches. The proposed fractional order QFT controllers offer the elimination of the overshoot and the undershoot from the closed loop response of the system; outperforms the existing controllers in terms of disturbance rejection; offers 0% steady-state deviation, while providing improved phase margin (60.1°) for enhanced stability compared to existing controllers. Also, the proposed QFT-GA attains the ideal values for both the peak complementary sensitivity functions; thus, establishing excellent robustness. Also, the proposed controllers ensure adequate tolerance to frequency deviation in case of load change.

Analysis and control design for input‐series output‐parallel multi‐channel inductive power transfer system

AbstractTo realize high‐power inductive power transfer (IPT) for fast charging of electric vehicles (EVs), an input‐series output‐parallel (ISOP) multi‐channel IPT system is analysed in this paper, and an output control strategy based on single neuron controller is proposed to improve the stability of the system. Firstly, the steady‐state operating conditions of ISOP‐IPT system is analysed based on different compensation networks which shows that the constant‐voltage‐output compensation networks are more suitable for the proposed circuit structure. Then, to improve the voltage equalization between channels, an open‐loop control method combining parameter design and phase‐shift control is proposed against different coil misalignments. At the same time, based on the single neuron controller, the system output closed‐loop control is realized without the need of accurate system modelling. Finally, a three‐channel ISOP‐IPT experimental system was constructed, which operated stably at 2.9 kW with a power efficiency of 93.38%. The system closed‐loop control with control time of 22 ms is realized. The voltage equalization control offset is less than 1%.

VMP: Versatile Motion Priors for Robustly Tracking Motion on Physical Characters

AbstractRecent progress in physics‐based character control has made it possible to learn policies from unstructured motion data. However, it remains challenging to train a single control policy that works with diverse and unseen motions, and can be deployed to real‐world physical robots. In this paper, we propose a two‐stage technique that enables the control of a character with a full‐body kinematic motion reference, with a focus on imitation accuracy. In a first stage, we extract a latent space encoding by training a variational autoencoder, taking short windows of motion from unstructured data as input. We then use the embedding from the time‐varying latent code to train a conditional policy in a second stage, providing a mapping from kinematic input to dynamics‐aware output. By keeping the two stages separate, we benefit from self‐supervised methods to get better latent codes and explicit imitation rewards to avoid mode collapse. We demonstrate the efficiency and robustness of our method in simulation, with unseen user‐specified motions, and on a bipedal robot, where we bring dynamic motions to the real world.

A novel satisfactory model predictive control based on current variance for high power three‐level‐NPC rectifiers

AbstractHere, a novel satisfactory model predictive control based on current variance (CV‐SMPC) is proposed for three level neutral point clamped (NPC) rectifiers. CV‐SMPC achieves global optimization of multiple control objectives rather than optimal control of a single control objective with the satisfaction interval. The current satisfaction interval is adjusted online based on the current variance in the CV‐SMPC. The relationship between the current total harmonic distortion (THD), switching frequency, and current variance is established through experimental investigation, enhancing the comprehensibility of control effects. In addition, three simplified sets of candidate vectors are proposed based on the voltage satisfaction interval, thereby reducing the computational burden. Furthermore, the control objectives are categorized into three levels and sequentially combined, eliminating the laborious process of adjusting the weighting factors. Finally, the experimental results conclusively demonstrate the exceptional control performance of CV‐SMPC in both steady‐state and dynamic processes.

Utilization of NIRS Monitor to Compare the Regional Cerebral Oxygen Saturation Between Dexmedetomidine and Propofol Sedation in Mechanically Ventilated Critically ill Patients with Sepsis- A Prospective Randomized Control Trial.

Delirium frequently occurs in the acute phase of sepsis and is associated with increased ICU and hospital length of stay, duration of mechanical ventilation, and higher mortality rates. We utilized the Near-Infrared Spectroscopy monitor to measure and compare the regional cerebral oxygen saturation in mechanically ventilated patients of sepsis receiving either dexmedetomidine or propofol sedation and assessed the association between delirium and regional cerebral oxygen saturation. A single center prospective randomized control trial conducted over a period of two years, 54 patients were included, equally divided between propofol and dexmedetomidine groups. Patients received a blinded study drug, propofol (10 mg/mL) or dexmedetomidine (5 mcg/mL) via infusion pump according to randomization. Infusion rates were adjusted every 10 min based on weight-based titration tables, aiming for target sedation (RASS -2 to 0). Management components included pain monitoring using the CPOT score and delirium assessment using CAM-ICU score. Dexmedetomidine group showed higher mean regional cerebral oxygen saturation as compared to propofol group (P = .036). No significant differences were found in mechanical ventilation or ICU stay durations, delirium-free days, or sedation cessation reasons. Delirium occurred in 36 patients, with lower mean regional cerebral oxygen saturation as compared to non-delirious patients. The dexmedetomidine group had higher regional cerebral oxygen saturation compared to the propofol group. Delirious patients showed lower cerebral oxygen saturation than non-delirious patients, suggesting a link between sedation type, cerebral oxygenation, and delirium.CTRI registration: REF/2021/11/048655 N.

Effect of herbal soup on immunological parameters of people living with HIV, Kenya - a parallel single blind randomized control trial

Effect of herbal soup on immunological parameters of people living with HIV, Kenya - a parallel single blind randomized control trial

Sequencing and phylogenetic analysis of the complete mitochondrial genome of the Eurasian Harvest Mouse (Micromys minutus) Pallas 1771 from China

This study aimed to examine the complete mitochondrial genome sequence of the Eurasian Harvest Mouse (Micromys minutus) through polymerase chain reaction. The mitochondrial genome of M. minutus was characterized as a circular, double-stranded DNA molecule, encompassing a total length of 16,239 bp. The mitochondrial genome composition of M. minutus was found to include 13 protein-coding genes, a single control region, 22 tRNA genes, 2 rRNA genes, and a origin of L-strand replication. The accurate identification, sequencing, and assembly of the M. minutus mitochondrial genome were successfully conducted in this study, providing a resource for the scientific community to accurately attribute the mitochondrial genome of this species.

The Eye and Nose Identification Chip Controller-Based on Robot Vision Using Weightless Neural Network Method

Increasingly advanced image analysis in computer vision, allowing computers to interpret, identify, and analyze pictures with accuracy comparable to humans. The availability of data sources in decimal, hexadecimal, or binary forms enables researchers to take the initiative in applying their study findings. Decimal formats are typically used on traditional computers like desktops and minicomputers, whereas hexadecimal and binary formats were utilized on single-chip controllers. Weightless Neural Network is a method that can be implemented in a single chip controller. The aim of this research is to develop a facial recognition system, for eye and mouth identification, that works in a single chip controller or also called a microcontroller. The suggested method is a Weightless Neural Network with Immediate Scan approach for processing and identifying eye and nose patterns. The data will be handled in many memory locations that are specifically designed to handle massive volumes of data. The data is made up of primary face data sheets and face input data. The data sets utilized are (x,y) pixels, and frame sizes range from 90x90 pixels to 110x110 pixels. Each face shot will be processed by selecting the region of the eyes and nose and saving it as an image file. The eye and nose will identify the face frame. Next, the photos will be converted to binary format. A magazine matrix will be used to transmit binary data from a minicomputer to a microcontroller via serial connection. Based on a known pattern, the resultant similarity accuracy is 83,08% for the eye and 84,09% for the sternum. In contrast, the similarity percentage for an eye ranges from 70% to 85% for an undefined pattern.