Motor Loss Research Articles

Experimental research on iron loss of high-speed spindle motor under variable frequency drive power supply

Experimental research on iron loss of high-speed spindle motor under variable frequency drive power supply

CNSC-06. NAVIGATING BRAIN CANCER: PATIENT STORIES AND MEDICAL BREAKTHROUGH

Abstract The complex interplay of genetic mutation, dys regulated signalling pathways, Epigenetic modifications and Interaction with tumor microenvironment are the major aggravating factors for Brain Tumors. Neurological complications involve Increased Intracranial pressure, Seizures, Motor and Sensory deficits, Aphasia, Hydrocephaly, Behavioral and personality changes, Cerebellar Symptoms. It is diagnosed in a sequential steps. Collecting good history from patient in primary then examining the patient all through and making some investigations to come to a final diagnosis. On asking history to a patient he complains of recurrent convulsions, Personality changes and some motor activity deficit and loss of few senses. On examination we can reveal defect in cranial nerve functions, Motor or sensory deficits, loss of reflexes and coordination. Then Investigations being the next step for diagnosis, We ask the patient to undergo for a test for Blood Biomarkers and CSF analysis in case of suspection of metastatic Brain tumors. Biopsy to obtain for Histopathological Examination. Histopathological examination is done for analysis of genetic mutations and molecular markers. The other imaging techniques like MRI, MRS, CT, PET, EEG are done. This gives a clear picture of what actually caused tumor and shows a way for treatment. Now the treatment involves both Medical and Surgical treatment. Medical treatment includes Chemotherapy along with radiation therapy where the drugs given are Temozolomide and targeted therapy included EGFR BRAF inhibitors for glioblastoma and low grade gliomas respectively. Tumor treating fields- Optune is given. Surgical treatment involves Craniotomy for removal of primary Brain tumors, Neuro Endoscopy if tumor is present in ventricles or base of Brain, Laser interstitial Thermal therapy for deap seated and recurrent brain tumors. This is all about the treatment and now the patient management is very important for further clinical help. Physical, occupational and speech therapy helps patients recover. Symptomatic approach for inoperable tumors Provide comprehensive support for patients nearing end of life, Emphasise confidence and Quality of life.

Design and Optimization of a Permanent Magnet Synchronous Motor for a Two-Dimensional Piston Electro-Hydraulic Pump

A two-dimensional (2D) piston electro-hydraulic pump has been proposed further to enhance the power density of the electro-hydraulic pump. The 2D piston pump, characterized by high power density and a slender shape, is embedded within the stator of the motor in a co-rotor configuration where the piston and the motor’s rotor are in tandem. The intimate design of the hydraulic pump and the motor results in a coupling between the two, with intricate relationships and influences existing between the geometric parameters of the piston pump and the dimensions of the motor’s rotor. Based on the operational requirements and structure of the 2D piston pump, a permanent magnet synchronous motor (PMSM) designed for use with a 2D piston electro-hydraulic pump is developed. This study examines the impact of the motor’s stator iron core geometric parameters on both the electromagnetic and mechanical properties of a PMSM and completes the necessary performance validations. The optimization objectives of the motor are determined through an analysis of the influence of the key parameters of the rotor and stator on torque, torque ripple, and motor loss. A surrogate optimization model is constructed using a metamodel of optimal prognosis (MOP) to optimize the torque, torque ripple, and motor loss. Evolutionary genetic algorithms are utilized to achieve the multi-objective optimization design. A finite element simulation is used to compare the electromagnetic performance of the initial motor and optimal motor. Based on the optimal motor parameters, a 2.5 kW motor prototype is manufactured, and the experimental results validate the feasibility and effectiveness of the motor design and optimization.

Dual Role of Ibuprofen and Indomethacin in Promoting Peripheral Nerve Regeneration In Vitro.

Peripheral nerve injuries (PNI) can result in significant losses of motor and sensory function. Although peripheral nerves have an innate capacity for regeneration, restoration of function after severe injury remains suboptimal. The gold standard for peripheral nerve regeneration (PNR) is autologous nerve transplantation, but this method is limited by the generation of an additional surgical site, donor-site morbidity, and neuroma formation at the site of harvest. Although targeted drug compounds have the potential to influence axonal growth, there are no drugs currently approved to treat PNI. Therefore, we propose to repurpose commonly used nonsteroidal anti-inflammatory drugs (NSAIDs) to enhance PNR, facilitating easier clinical translation. Additionally, calcium signaling plays a crucial role in neuronal connectivity and regeneration, but how specific drugs modulate this process remains unclear. We developed an in vitro hollow channel collagen gel platform that successfully supports neuronal network formation. This study evaluated the effects of commonly used NSAIDs, namely ibuprofen and indomethacin, in our in vitro model of axonal growth, regeneration, and calcium signaling as potential treatments for PNI. Our results demonstrate enhanced axonal growth and regrowth with both ibuprofen and indomethacin, suggesting a positive influence on PNR. Further, these drugs showed enhanced calcium signaling dynamics, which we posit is a crucial aspect for nerve repair. Taken together, these findings highlight the potential of ibuprofen and indomethacin to be used as treatment options for PNI, given their dual capability to promote axonal growth and enhance calcium signaling.

Cytosolic Phospholipase A2 in Infiltrating Monocyte-Derived Macrophages Does Not Impair Recovery After Spinal Cord Injury in Female Mice.

Spinal cord injury (SCI) leads to permanent motor and sensory loss that is exacerbated by intraspinal inflammation that persists months to years after injury. After SCI, monocyte-derived macrophages (MDMs) infiltrate the lesion to aid in myelin-rich debris clearance. During debris clearance, MDMs adopt a proinflammatory phenotype that exacerbates neurodegeneration and hinders recovery. The underlying cause of the lipid-mediated MDM phenotype shift is unclear. Our previous work suggests that cytosolic phospholipase A2 (cPLA2) plays a role in the proinflammatory potentiating effect of myelin on macrophages in vitro . Cytosolic phospholipase A2 (cPLA2) frees arachidonic acid from phospholipids, generating eicosanoids that play an important role in inflammation, immunity, and host defense. cPLA2 is expressed in macrophages along with multiple other cell types after SCI, and cPLA2 inhibition has been reported to both reduce and exacerbate secondary injury pathology recovery. The role of cPLA2 in MDMs after SCI is not fully understood. We hypothesize that cPLA2 activation in MDMs after SCI contributes to secondary injury. Here, we report that cPLA2 plays an important role in the myelin-induced inflammatory macrophage phenotype in vitro using macrophages derived from cPLA2 knockout bone marrow. Furthermore, to investigate the role of cPLA2 in MDMs after SCI, we generated female bone marrow chimeras using cPLA2 knock-out donors and assessed locomotor recovery using the Basso Mouse Scale (BMS), CatWalk gait analysis system, and horizontal ladder task over six weeks. We also evaluated tissue sparing and intralesional axon density six weeks after injury. cPLA2 KO chimeras did not display altered locomotor recovery or tissue pathology after SCI compared to WT chimera controls. These data suggest that although cPLA2 plays a critical role in myelin-mediated potentiation of proinflammatory macrophage activation in vitro , it may not contribute to secondary injury pathology in vivo after SCI.

Research on Performance of Interior Permanent Magnet Synchronous Motor with Fractional Slot Concentrated Winding for Electric Vehicles Applications

The fractional-slot, concentrated-winding, interior permanent magnet synchronous motor (FSCW IPMSM) has advantages, such as reducing motor copper consumption, improving flux-weakening capability, and motor fault tolerance, and has certain development potential in application fields such as electric vehicles. However, fractional-slot concentrated-winding motors often contain rich harmonic components due to their winding characteristics, leading to increased motor losses and back electromotive force harmonics, thereby affecting the efficiency and constant power speed regulation range of the motor. Based on this, this article first uses the winding function method to explore the inductance and saliency ratio of the interior permanent magnet synchronous motor with different slot pole combinations in the fractional-slot concentrated- winding of electric vehicles. Secondly, this article will establish a 2D finite element parameterized model to analyze and compare the performance of fractional-slot concentrated-winding motors with different slot pole combinations, including air gap magnetic density, back electromotive force distortion rate, overload multiple, and torque. The structural parameters of the motor were optimized with the objective of minimizing the torque ripple under the constraint of minimizing the average torque reduction. The motor slot width, permanent magnet angle, and permanent magnet pole arc angle were analyzed and optimized. The simulation results showed that 12 slots and 8 poles were the optimal design schemes, providing a theoretical basis for the selection of slot pole coordination in the fractional-slot concentrated-winding interior permanent magnet synchronous motor for electric vehicles.

Operational electricity cost reduction using real-time simulators

Ensuring the safe and cost-effective electricity transmission to consumers, along with the efficient and sustainable operation of power systems, has long been a primary objective for power system managers and operators. However, achieving optimal performance in a modern power system requires timely planning and operational optimal routines to be run within the realm of real-time simulation programs, and sometimes, the divergence becomes a problem with these developed routines. Despite extensive research aimed at advancing these objectives, the growing complexity of networks and their constraints has often led to the oversight of simultaneously considering both technical and economic aspects during operation. In this paper, an innovative real-time framework is introduced to reduce the operational costs of a power system swiftly. This framework addresses various nonlinear constraints, such as transmission losses, generation-consumption balance, power device limitations, and transient stability constraints, across various operational scenarios within a real-time simulator. This novel approach leverages scattered search and intentional contingencies within the network to pinpoint the optimal operating point, taking into account various network dynamics, including Automatic Voltage Regulators (AVR), governors, and tap of the transformers. The proposed method offers a fast and robust approach to identifying the most effective operating conditions for a power system. It incorporates considerations for sudden contingencies and extends capabilities through parallel simulations. It not only facilitates pre-determined preventive actions but also enables the adjustment of control parameters during post-contingency periods, such as fine-tuning of the active and reactive power generation of generators and adjusting the tap settings of transformers within power networks. Since the network simulation can be executed on distributed computers, referred to as ’Global,’ it is possible to achieve global network optimization. This approach allows for the consideration of grid networks, including renewable energy sources with models distributed through PCs. Also, it accounts for the induction motor losses within all factories involved in the global simulation. The results obtained from simulating the proposed method on a commercial real-time simulator demonstrate the superior effectiveness of the proposed framework compared to the existing methodologies, highlighting its potential to enhance the operational efficiency and economic viability of power systems.

Peripheral nerve grafting

Peripheral nerve lesions often lead to significant and permanent loss of motor and sensory function. The aim of peripheral nerve grafting is to bridge nerve defects. When tension-free nerve repair is not possible, peripheral nerve grafting is indicated. Local infection, insufficient soft tissue coverage, significant muscle atrophy or joint contraction in case of "motor" nerve grafting, lack of microsurgical instruments or experience, life-threatening injuries. Exposure and preparation of the nerve stumps. Choosing and preparation of the donor nerve. Approximation. Nerve repair. Nerve reconstruction must always be tension-free as nerve repair with tension frequently leads to disruption of nerve healing and poor functional outcome. Autologous nerve grafting from various donor sites leads to excellent functional results with little sensory deficits at the donor regions. Limited immobilization, physiotherapy, ergotherapy, regular clinical and neurological assessments. Outcome of peripheral nerve grafting may, for example, depend on defect length, caliber and quality of the injured nerve, quality of the donor nerve, microsurgical expertise of the surgeon, time of reconstruction, and age of the patient.

Comparison of Several Energy-Efficient Control Laws Using Energetic Macroscopic Representation for Electric Vehicles

Energy transition and decarbonization present significant challenges to transportation. Electric machines, such as motors and generators, are increasingly replacing internal combustion engines to reduce greenhouse gas emissions. This study focuses on enhancing the energy efficiency of electric machines used in vehicles, which are predominantly powered by batteries with limited energy capacity. By investigating various control strategies, the aim is to minimize energy losses and improve overall vehicle performance. This research examines two types of electric motors: Permanent Magnet Synchronous Motor (PMSM) and Induction Motor (IM). Real-time loss measurements were conducted during simulated driving cycles, including acceleration, constant speed, and braking phases, to mimic typical driving behavior. The simulation utilized characteristics from commercial vehicles, specifically the Renault Zoé and Bombardier eCommander, to assess the controls under different configurations. This study employed the Energetic Macroscopic Representation (EMR) formalism to standardize the analysis across different motors and controls. The results demonstrate significant loss reductions. The controls investigated in this study effectively reduce energy losses in electric motors, supporting their applicability in the automotive industry.

Effect of friction layer thickness on energy conversion efficiency of traveling wave rotary ultrasonic motor

Abstract Due to its compact size and resistance to electromagnetic interference. Applications for traveling wave rotary ultrasonic motors (TRUM) include robotic joint drives and aerospace.The motor’s energy conversion efficiency is impacted by the characteristics of the friction layer, yet the underlying mechanism influencing the efficiency remains unreported. Using the previously created finite element model, the mechanism via which the amount of thickness within the friction layer influences the motor output characteristics is examined.Analysis is done on the variations in motor loss, energy conversion efficiency, and input-output characteristics. The computation results show that when the friction layer is less than 0.4 mm, the machine’s output speed increases as the friction layer’s thickness decreases.The results of the calculation indicate that when the friction layer thickness is between 0.05 and 0.4 mm, the motor’s output torque and speed would drop. The findings indicate that the output torque and motor torque decrease as the friction layer thickness increases when it is between 0.05 and 0.4 mm. Both the viscoelastic losses and the motor’s energy conversion efficiency rise.Research shows that the friction layer thickness has a huge impact on the motor and cannot be ignored, providing a reference for the application of motors in industries such as robot joints.

Neuromuscular junction dysfunction in Lafora disease.

Lafora disease (LD), a fatal neurodegenerative disorder, is caused by mutations in the EPM2A gene encoding laforin phosphatase or NHLRC1 gene encoding malin ubiquitin ligase. LD symptoms include epileptic seizures, ataxia, dementia and cognitive decline. Studies on LD have primarily concentrated on the pathophysiology in the brain. A few studies have reported motor symptoms, muscle weakness and muscle atrophy. Intriguingly, skeletal muscles are known to accumulate Lafora polyglucosan bodies. Using laforin-deficient mice, an established model for LD, we demonstrate that LD pathology correlated with structural and functional impairments in the neuromuscular junction (NMJ). Specifically, we found impairment in NMJ transmission, which coincided with altered expression of NMJ-associated genes and reduced motor endplate area, fragmented junctions and loss of fully innervated junctions at the NMJ. We also observed a reduction in alpha-motor neurons in the lumbar spinal cord, with significant presynaptic morphological alterations. Disorganised myofibrillar patterns, slight z-line streaming and muscle atrophy were also evident in LD animals. In summary, our study offers insight into the neuropathic and myopathic alterations leading to motor deficits in LD.

Evaluation of Rehabilitation Techniques for Traumatic Ulnar Nerve Injuries After Surgical Repair: A Systematic Review.

Traumatic ulnar nerve injuries often result in significant loss of motor and sensory function, negatively impacting patients' quality of life. Physical rehabilitation is crucial for recovery, but standardized treatment protocols are lacking. This study aims to systematically review rehabilitation techniques to identify future research direction and improve existing protocols for ulnar nerve injury patients. PubMed, Embase, CINAHL, Cochrane CENTRAL, Web of Science, and Scopus were queried from inception until July 31, 2023. Articles containing axonotmesis or neurotmesis injuries of the ulnar nerve were included. Reviews, opinions, editorials, technical reports without clinical outcomes, conference abstracts, non-English text, nonhuman studies, and studies without adult patients were excluded. Three independent reviewers performed screening and data extraction using Covidence, and risk of bias assessments utilizing Cochrane and JBI tools. Because of article heterogeneity, a narrative review was conducted. The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database, registration number CRD42023442016. This systematic review included one randomized controlled trial and four observational studies (103 patients), which exhibited differences in study quality. Overall, motor and sensory outcomes improved after rehabilitation. Rehabilitation techniques varied widely, and early sensory reeducation appeared to improve sensory function. Only two studies included patient-reported outcomes. Diverse rehabilitation techniques are used to address ulnar nerve injuries. The low number of included studies, differences in study quality, and small sample size underscore the need for larger and more inclusive studies to improve functional recovery after ulnar nerve injuries. Future research should consider the impact of patient and injury characteristics to develop comprehensive treatment guidelines for these patients.

Thermodynamic performance and compression characteristics analysis of low GWP refrigerant in compressors: Experimental investigation and 0-D/3-D simulation

The utilization of low global warming potential (GWP) refrigerants is crucial for reducing greenhouse gas emissions. Among these alternatives for hydrofluorocarbons (HFCs), R290 stands out as a natural refrigerant with a low GWP value of 3. Therefore, it is beneficial to promote its widespread adoption and enhance the efficiency of compressors and their systems that utilize R290 to mitigate the greenhouse effect. The present study investigates and compares the thermodynamic performance and compression characteristics of a high-speed compressor employing R290 as a refrigerant with those of an R32 compressor. In contrast to previous studies, this paper presents a novel approach by developing validated the zero-dimensional (0-D) and three-dimensional (3-D) simulation model, along with experiments, to investigate the distribution of performance loss and suction-compression characteristics in high-speed R290 compressors. The results demonstrate that the R290 compressor exhibits superior volumetric efficiency, while excessive compression at high speeds leads to a noticeable reduction in indicated power. The combination of increased over-compression loss and motor loss at high speeds resulted in a 11.7% rise in input power, leading to an 8.4% decline in thermodynamic performance for the R290 compressor under standard heating compared to the R32 compressor.

MiR-NPs-RVG promote spinal cord injury repair: implications from spinal cord-derived microvascular endothelial cells

BackgroundSpinal cord injury (SCI) often leads to a loss of motor and sensory function. Axon regeneration and outgrowth are key events for functional recovery after spinal cord injury. Endogenous growth of axons is associated with a variety of factors. Inspired by the relationship between developing nerves and blood vessels, we believe spinal cord-derived microvascular endothelial cells (SCMECs) play an important role in axon growth.ResultsWe found SCMECs could promote axon growth when co-cultured with neurons in direct and indirect co-culture systems via downregulating the miR-323-5p expression of neurons. In rats with spinal cord injury, neuron-targeting nanoparticles were employed to regulate miR-323-5p expression in residual neurons and promote function recovery.ConclusionsOur study suggests that SCMEC can promote axon outgrowth by downregulating miR-323-5p expression within neurons, and miR-323-5p could be selected as a potential target for spinal cord injury repair.Graphical

Laser‐scribed graphene toward scalable fabrication of electrochemical paper-based devices for lidocaine detection in forensic and pharmaceutical samples

Lidocaine (LID), a tertiary amine drug, is widely used as a local anesthetic for topical anesthesia and also presents antiarrhythmic and analgesic properties. Given its use can induce a temporary loss of sensory, motor, and autonomic function, it has been associated with criminal instances of drug-facilitated sexual assault. Herein, we manufactured an electrochemical paper-based analytical device (ePAD) using the laser-scribed graphene (LSG) technique for LID detection in pharmaceutical and forensic applications. The paper-based devices were characterized by scanning electron microscopy (SEM) and Raman spectroscopy, confirming the porosity and graphene-derived nature of the LSG material. In addition, to enhance the electrocatalytic properties, the LSG electrode was modified with a nanocomposite based on the mixture of multi-walled carbon nanotubes (MWCNT) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). Electrochemical characterizations of the non-modified and MWCNT/PEDOT:PSS-modified electrodes by impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV), revealed the enhancement of the electrochemical properties of the modified electrode, providing higher detectability for LID detection. An analytical curve was built using DPV technique and exhibited a linear response in the concentration range of 31 to 248 µmol L−1 LID. The limits of detection (LOD) and quantification (LOQ) of the method were 0.72 µmol L−1 and 2.39 µmol L−1, respectively. The manufacturing reproducibility of the method was assessed by testing 8 sensors from different batches and provided a relative standard deviation (RSD) of 4.92 % (n = 8). The developed sensor was applied to LID determination in a commercial anesthetic sample and, as proof of the applicability of potential use in crime scenes of drug-facilitating crimes, we analyzed spiked LID in alcoholic drinks (vodka and tequila samples). The recovery percentages ranged from 79 % to 109 %, highlighting the practical use of our portable method for in-field analysis. In addition, four seized cocaine samples containing LID were successfully analyzed to demonstrate the potential use as a LID screening tool in street drug samples.

The Effect of Tissue Inhibitor of Metalloproteinases on Scar Formation after Spinal Cord Injury.

Spinal cord injury (SCI) often results in permanent loss of motor and sensory function. After SCI, the blood-spinal cord barrier (BSCB) is disrupted, causing the infiltration of neutrophils and macrophages, which secrete several kinds of cytokines, as well as matrix metalloproteinases (MMPs). MMPs are proteases capable of degrading various extracellular matrix (ECM) proteins, as well as many non-matrix substrates. The tissue inhibitor of MMPs (TIMP)-1 is significantly upregulated post-SCI and operates via MMP-dependent and MMP-independent pathways. Through the MMP-dependent pathway, TIMP-1 directly reduces inflammation and destruction of the ECM by binding and blocking the catalytic domains of MMPs. Thus, TIMP-1 helps preserve the BSCB and reduces immune cell infiltration. The MMP-independent pathway involves TIMP-1's cytokine-like functions, in which it binds specific TIMP surface receptors. Through receptor binding, TIMP-1 can stimulate the proliferation of several types of cells, including keratinocytes, aortic smooth muscle cells, skin epithelial cells, corneal epithelial cells, and astrocytes. TIMP-1 induces astrocyte proliferation, modulates microglia activation, and increases myelination and neurite extension in the central nervous system (CNS). In addition, TIMP-1 also regulates apoptosis and promotes cell survival through direct signaling. This review provides a comprehensive assessment of TIMP-1, specifically regarding its contribution to inflammation, ECM remodeling, and scar formation after SCI.

"White Cord Syndrome" as clinical manifestation of the spinal cord reperfusion syndrome: a systematic review of risk factors, treatments, and outcome.

Paralysis subsequent to spinal cord decompression in the cervical or thoracic region is infrequent, with White Cord Syndrome (WCS) being among its several causes. Due to WCS's infrequency, there exists a paucity of high-level evidence concerning its manifestations. Our primary objective is to systematically collate all documented WCS cases, discern prevalent risk and prognostic factors, appraise available treatment modalities, and evaluate patient outcomes. A systematic review was conducted following PRISMA guidelines. The search included PubMed, Scopus, Embase, and Web of Science databases. Inclusion criteria required studies to be written in English, be case reports, and contain data on clinical features, management, and treatment outcomes. Exclusion criteria excluded meta-analyses, reviews, editorials, letters, books, studies with insufficient clinical data, and studies not in English or with unavailable full texts. Grey literature was not actively pursued due to identification challenges, potentially introducing selection bias. Two authors independently evaluated papers based on criteria. Disagreements were resolved with a third author. Additionally, the included articles' references were screened for additional relevant articles. We found a total of 580 articles through our electronic search. After removing duplicates, 399 articles were screened. Out of the remaining 51 studies, 27 were included in the final quantitative analysis. The average age was 54 (3-79 years) with a male-to-female ratio of 2:1, 33% had OPLL, and Common medical histories were hypertension (30%), diabetes mellitus (20%), and previous ACDF surgery (8%). Of all Surgeries, 70% were done with a posterior approach and 30% with the anterior approach. 48% of cases used Intraoperative NeuroMonitoring(IONM), and Loss of Motor Evoked Potentials (MEP) occurred in 37% of cases. Patients received high-dose intravenous steroids. In 26% of cases, additional posterior cervical decompression was performed, and efforts were made to maintain mean arterial pressure above 85 mmHg in 37% of cases. Other medications were administered in 30% of cases. Over an average 26-week follow-up, 37% of patients had good recovery, 40% had partial recovery, and 23% showed no recovery. The average final Nurick grade was 3.2. WCS is a rare cause of postoperative neurological deficit following spinal cord decompression surgery. Risk factors for WCS include advanced age, extensive surgery, posterior approach for decompression, and the presence of OPLL. Treatment includes high-dose steroids, posterior cervical decompression, maintaining MAP over 85mmHg, rehabilitation, and sometimes neurotrophic drugs. Most patients can walk with or without assistance during follow-up, but around a quarter never regain neurological function. The only preoperative factor impacting outcomes is the preoperative neurological status (Nurick Grade).

Collagen protein-chitosan nerve conduits with neuroepithelial stem cells promote peripheral nerve regeneration

The peripheral nervous system consists of ganglia, nerve trunks, plexuses, and nerve endings, that transmit afferent and efferent information. Regeneration after a peripheral nerve damage is sluggish and imperfect. Peripheral nerve injury frequently causes partial or complete loss of motor and sensory function, physical impairment, and neuropathic pain, all of which have a negative impact on patients’ quality of life. Because the mechanism of peripheral nerve injury and healing is still unclear, the therapeutic efficacy is limited. As peripheral nerve injury research has processed, an increasing number of studies have revealed that biological scaffolds work in tandem with progenitor cells to repair peripheral nerve injury. Here, we fabricated collagen chitosan nerve conduit bioscaffolds together with collagen and then filled neuroepithelial stem cells (NESCs). Scanning electron microscopy showed that the NESCs grew well on the scaffold surface. Compared to the control group, the NESCs group contained more cells with bigger diameters and myelinated structures around the axons. Our findings indicated that a combination of chitosan-collagen bioscaffold and neural stem cell transplantation can facilitate the functional restoration of peripheral nerve tissue, with promising future applications and research implications.

Comparison and analysis of properties of V-type HV-LSPMSM with non-magnetic and magnetic-wedges

In order to improve the magnetic density distribution and torque ripple waveform of the motor and enhance its efficiency, the effect of slot wedge on motor performance is discussed in this paper. Taking 6 kV, 710 kW high-voltage line-start PMSM (HV-LSPMSM) as an example, the mathematical model is established, the influence mechanism of slot wedge on air gap density, loss, efficiency and torque ripple of motor is analyzed. The HV-LSPMSM prototype was manufactured, the deviations of several important motor parameters are less than 5% by comparing the test data and the finite element analysis (FEA) results, thus, the accuracy and reliability of the modified finite element model (FEM) are verified, it provides an experimental basis for further research on the effect of relative permeability variation on motor performance. The effects of nonmagnetic-wedges and magnetic-wedges on the motor’s performance are systematically compared. The research results show that compared with the non-magnetic wedges, the magnetic wedges are used to make the magnetic density more uniform, the eddy current loss with magnetic wedge (μ = 5) is reduced by 7.292 kW, and the motor efficiency is improved. The torque ripple rate with magnetic wedge (μ = 3) is reduced by 3.35%, and the torque waveform is significantly improved. And It is found that magnetic wedge (μ > 3) slowed down the iron loss reduction rate. The research provides an important theoretical and experimental basis for the design of HV-LSPMSM and the application of magnetic-wedge in motor.

Design of a Linear Motor: An Optimization Approach Considering Motor and Inverter Losses With Different Voltage Waveforms

Design of a Linear Motor: An Optimization Approach Considering Motor and Inverter Losses With Different Voltage Waveforms