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1.
Surgery ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38910046

RESUMO

BACKGROUND: Postoperative delirium is a severe complication of flap transplantation surgery, adversely affecting surgical prognoses. The intricate pathophysiology of postoperative delirium renders the elucidation of its risk factors challenging. This research aims to delineate the prevalence and the specific risk factors of postoperative delirium in patients with cancer undergoing free flap reconstruction through a systematic review and meta-analysis to enlighten proactive prevention measures. METHODS: The researchers systematically queried both the international and Chinese databases. Searches were performed for publications from inception until September 14, 2023, using the terms "free tissue flaps," "delirium," "neoplasms," and "risk factors." Data synthesis and statistical analysis were conducted using Stata SE (version 15.0) to calculate the combined effect size for identified risk factors. Reported outcomes included weighted mean differences or odds ratios with their respective 95% confidence intervals. RESULTS: Twelve case-control studies were included (ntotal = 3,256). Among them, 515 patients developed postoperative delirium after free flap surgery, compared with 2,741 patients who did not. The outcomes suggest that the risk factors include but are not limited to age, male, late neoplasm staging, use of hypnotic or antipsychotic, history of background diseases, psychiatric review, tracheotomy, and impaired wound healing. In contrast, early neoplasm staging and others are the protective factors with statistical significance. Multivariate analysis further identified significant correlations between preoperative albumin, perioperative blood transfusion, sleep disturbance, postoperative visual analog scale, postoperative albumin, smoking, and the appearance of postoperative delirium. CONCLUSION: The determined risk factors were grouped into preoperative, intraoperative, and postoperative categories substantiated by current data to present instructions for postoperative delirium prevention.

2.
Biomed Mater ; 19(4)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38901421

RESUMO

Nowadays, medical polyurethanes with favorable and durable antibacterial properties received more attention, because of avoiding repeated replacement of interventional materials and reducing patients' pain. In this thesis, non-soluble antibacterial polyurethane (NAPU) based on cation antibacterial mechanism was prepared by photo-grafting chitosan azide and heparin azide into polyurethane (PU). -NH3+of chitosan azide absorbed bacteria, inhibiting and breaking their mobility and structures. Heparin azide prevented cations from penetrating bacteria's membranes and inhibited their growth. The results showed that chitosan azide and heparin azide were successfully grafted into PU. The highest antibacterial rate was 92.07%, cytotoxicity grade ranging from 0-1 (RGR standard) and water contact angle exhibiting 60°, attributing to cation antibacterial effect and -OH existing. Tensile strength was up to 23.91 MPa and was suitable for using as medical materials. NAPU with long-lasting coating both possessed antibacterial properties and persistence, which can solve the problem of medical catheters' long-term using.


Assuntos
Antibacterianos , Azidas , Cátions , Quitosana , Heparina , Poliuretanos , Poliuretanos/química , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Heparina/química , Azidas/química , Teste de Materiais , Resistência à Tração , Escherichia coli/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Animais , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Camundongos , Solubilidade
3.
Intractable Rare Dis Res ; 13(2): 73-88, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38836174

RESUMO

Epidemiological data on rare diseases in China are currently limited. The objective of this study was to provide a comprehensive understanding of the prevalence and incidence of rare diseases by systematically analyzing the available epidemiological data. We conducted a comprehensive search of English and Chinese databases, the Incidence and Prevalence Database, the Chinese Rare Disease Guideline, and the Taiwan Health Promotion Administration from 2010 to 2023. We identified the top diseases and regions based on epidemiological data and present the maximum, minimum, and median prevalence and incidence values in tables and forest plots. 1,264 prevalence and incidence data were retrieved from 277 studies, guidelines and official websites, covering 110 rare diseases (53.1%) and 32 regions (94.1%). In terms of geographical regions, incidence or prevalence data were available for 32 regions (94.1%), excluding Tibet Hui Autonomous Region and Macao Special Administrative Region. In terms of rate, 60 and 77 out of 207 diseases (29.0% and 37.2%) had available incidence and prevalence data, respectively. Eight diseases had an incidence rate equal to or greater than that of 1,000 patients per million. The present study provides a comprehensive epidemiological analysis and valuable insights into the prevalence and incidence of rare diseases in China. Our findings underscore the pressing need for sustained drug research and medical support for individuals and families impacted by rare diseases.

4.
Front Pharmacol ; 15: 1398381, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38694924

RESUMO

Cardiovascular diseases (CVDs) are currently the leading cause of death worldwide. In 2022, the CVDs contributed to 19.8 million deaths globally, accounting for one-third of all global deaths. With an aging population and changing lifestyles, CVDs pose a major threat to human health. Mitochondria-associated endoplasmic reticulum membranes (MAMs) are communication platforms between cellular organelles and regulate cellular physiological functions, including apoptosis, autophagy, and programmed necrosis. Further research has shown that MAMs play a critical role in the pathogenesis of CVDs, including myocardial ischemia and reperfusion injury, heart failure, pulmonary hypertension, and coronary atherosclerosis. This suggests that MAMs could be an important therapeutic target for managing CVDs. The goal of this study is to summarize the protein complex of MAMs, discuss its role in the pathological mechanisms of CVDs in terms of its functions such as Ca2+ transport, apoptotic signaling, and lipid metabolism, and suggest the possibility of MAMs as a potential therapeutic approach.

5.
Genome Med ; 16(1): 3, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185709

RESUMO

Identifying pathogenic variants from the vast majority of nucleotide variation remains a challenge. We present a method named Multimodal Annotation Generated Pathogenic Impact Evaluator (MAGPIE) that predicts the pathogenicity of multi-type variants. MAGPIE uses the ClinVar dataset for training and demonstrates superior performance in both the independent test set and multiple orthogonal validation datasets, accurately predicting variant pathogenicity. Notably, MAGPIE performs best in predicting the pathogenicity of rare variants and highly imbalanced datasets. Overall, results underline the robustness of MAGPIE as a valuable tool for predicting pathogenicity in various types of human genome variations. MAGPIE is available at https://github.com/shenlab-genomics/magpie .


Assuntos
Genoma Humano , Aprendizado de Máquina , Humanos
6.
Adv Mater ; 36(21): e2312799, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38263756

RESUMO

It is challenging to detect and differentiate multiple diseases with high complexity/similarity from the same organ. Metabolic analysis based on nanomatrix-assisted laser desorption/ionization mass spectrometry (NMALDI-MS) is a promising platform for disease diagnosis, while the enhanced property of its core nanomatrix materials has plenty of room for improvement. Herein, a multidimensional interactive cascade nanochip composed of iron oxide nanoparticles (FeNPs)/MXene/gold nanoparticles (AuNPs), IMG, is reported for serum metabolic profiling to achieve high-throughput detection of multiple liver diseases. MXene serves as a multi-binding site and an electron-hole source for ionization during NMALDI-MS analysis. Introduction of AuNPs with surface plasmon resonance (SPR) properties facilitates surface charge accumulation and rapid energy conversion. FeNPs are integrated into the MXene/Au nanocomposite to sharply reduce the thermal conductivity of the nanochip with negligible heat loss for strong thermally-driven desorption, and construct a multi-interaction proton transport pathway with MXene and AuNPs for strong ionization. Analysis of these enhanced serum fingerprint signals detected from the IMG nanochip through a neural network model results in differentiation of multiple liver diseases via a single pass and revelation of potential metabolic biomarkers. The promising method can rapidly and accurately screen various liver diseases, thus allowing timely treatment of liver diseases.


Assuntos
Ouro , Hepatopatias , Nanopartículas Metálicas , Ouro/química , Hepatopatias/diagnóstico , Hepatopatias/metabolismo , Nanopartículas Metálicas/química , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Nanocompostos/química , Metabolômica/métodos , Ressonância de Plasmônio de Superfície/métodos , Biomarcadores/sangue
7.
Int J Pediatr Otorhinolaryngol ; 176: 111817, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38071836

RESUMO

PURPOSE: In recent years, 3D printing technology has been employed as a production method that builds materials layer upon layer, providing notable advantages in terms of individual customization and production efficiency. Autologous costal cartilage ear reconstruction has seen substantial changes due to 3D printing technology. In this context, this research evaluated the prospects and applications of 3D printing in ear reconstruction education, preoperative planning and simulation, the production of intraoperative guide plates, and other related areas. METHODOLOGY: All articles eligible for consideration were sourced through a comprehensive search of PubMed, the Cochrane Library, EMBASE, and Web of Science from inception to May 22, 2023. Two reviewers extracted data on the manufacturing process and interventions. The Cochrane risk of bias tool and Newcastle-Ottawa scale were used to assess the quality of the research. Database searching yielded 283 records, of which 24 articles were selected for qualitative analysis. RESULTS: The utilization of 3D printing is becoming increasingly widespread in autogenous costal cartilage ear reconstruction, from education to the application of preoperative design and intraoperative guide plates production, possessing a substantial influence on surgical training, the enhancement of surgical effects, complications reduction, and so forth. CONCLUSION: This study sought to determine the application value and further development potential of 3D printing in autologous costal cartilage ear reconstruction. However, there is a lack of conclusive evidence on its effectiveness when compared to conventional strategies because of the limited number of cohort studies and randomized controlled trials. Simultaneously, the evaluation of the effect lacks objective and quantitative evaluation criteria, with most of them being emotional sentiments and ratings, making it difficult to execute a quantitative synthetic analysis. It is hoped that more large-scale comparative studies will be undertaken, and an objective and standard effect evaluation system will be implemented in the future.


Assuntos
Cartilagem Costal , Procedimentos de Cirurgia Plástica , Humanos , Cartilagem Costal/transplante , Orelha Externa/cirurgia , Impressão Tridimensional , Cartilagem da Orelha/cirurgia
8.
Int J Pharm ; 650: 123660, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38072148

RESUMO

Overcoming the vaginal barrier to achieve sufficient drug penetration and retention is a huge obstacle for drug delivery in chemotherapeutics for cervical cancer. In this study, we investigate the feasibility of a novel composite nanocrystal/nanofiber system for improving the transmucus penetration and, thus, enhancing retention and drug delivery to the lesion of a cervicovaginal tumor. Herein, paclitaxel (PTX) was sequentially formulated in the form of nanocrystals, coated with polydopamine (PDA), and modified with PEG. The nanocrystals (NCs@PDA-PEG) were creatively fabricated to create a composite nanofibrous membrane (NCs@PDA-PEG NFs) by using an electrospinning technique. The morphology, size distribution, drug loading, encapsulation efficiency, X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectra, in vitro release, in vivo vaginal retention, apoptosis index, anti-tumor efficacy in a murine cervicovaginal tumor model, and local irritation were characterized. The NCs@PDA-PEG were formulated in a cube-like shape with an average size of 385.6 ± 35.47 nm; they were dispersed in electrospun nanofibers, and the drug loading was 7.94 %. The XRD curves indicated that the phase state of PTX changed after the creation of the nanocrystals. The FTIR spectra showed that the drug and the excipients were compatible with each other. In vitro delivery showed that the dissolution of PTX in the electrospun nanofibers was significantly faster than that when using bulk PTX. Compared with the PTX NC NFs, the NC@PDA-PEG NFs exhibited prolonged vaginal residence, superior transmucus penetration, minimal mucosal irritation, and significant tumor inhibition efficacy after the intravaginal administration of the NFs in tumor-bearing mice. In conclusion, by acting as novel pharmaceutical repositories, NCs@PDA-PEG NFs can be promising candidates for non-invasive local treatment, leading to efficient tumor inhibition in cervicovaginal cancer.


Assuntos
Nanofibras , Nanopartículas , Neoplasias , Feminino , Animais , Camundongos , Nanofibras/química , Polietilenoglicóis/química , Paclitaxel/química , Nanopartículas/química , Linhagem Celular Tumoral
9.
ACS Appl Mater Interfaces ; 15(42): 49653-49664, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37846868

RESUMO

Efficient thermal management is critical to ensure the safe and reliable operation of lithium-ion batteries (LIBs) as they are highly sensitive to temperature changes. Meanwhile, LIBs are exposed to various external forces during operation, such as vibration, shock, and oscillation, which may disrupt the physical and chemical processes inside the battery and lead to a decreased performance and shortened life. Here, we designed a phase change hydrogel (PCH) pad based on the polyurethane (PU) foam skeleton and demonstrated its effectiveness in efficient thermal management and improving antivibration performance. The thermal conductivity of the prepared composite is 0.65 W/(m·K), while the thermal contact resistance could decrease to ∼20 K·cm2/W under 60 °C. It exhibits a flexible contact transformation during the phase transition, resulting in enhanced interfacial heat transfer and storage rate, as well as improved resistance against external impacts. The temperature of the battery module wrapped with a composite plate decreases by 11.4 °C during the 6C discharge. Moreover, the additional heat generated by external vibration is only half that of the bare battery, and the temperature difference could reach 5.2 °C, demonstrating the effective buffering effect of PCH@PU in mitigating long-term discharge-induced increases in internal resistance. The developed PCH@PU, known for its exceptional thermal management and favorable antivibration performance, holds promising potential for widespread utilization in the field of power battery heat dissipation.

10.
J Nat Prod ; 86(10): 2333-2341, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37819880

RESUMO

Linaridins are a family of underexplored ribosomally synthesized and post-translationally modified peptides despite the prevalence of their biosynthetic gene clusters (BGCs) in microbial genomes, as shown by bioinformatic studies. Our genome mining efforts reveal that 96 putative oxidoreductase genes, namely, LinC, are encoded in linaridin BGCs. We heterologously expressed two such LinC-containing linaridin BGCs, yan and ydn, from Streptomyces yunnanensis and obtained three new linaridins, named yunnanaridins A-C (1-3). Their structures are characterized by Z-configurations of the dehydrobutyrines and the presence of a variety of epimerized amino acid residues. Yunnanaridin A (1) is the sixth member of the family of type-B linaridins, whereas yunnanaridins B (2) and C (3) represent the first examples of expressed type-C linaridins. Interestingly, heterologous expression of the same BGCs with LinC in-frame knockouts produced the same compounds. This work expands the structural diversity of linaridins and provides evidence for the notion that the widespread LinCs may not be involved in linaridin biosynthesis.


Assuntos
Biologia Computacional , Peptídeos , Peptídeos/química , Família Multigênica , Aminoácidos
11.
Ann Plast Surg ; 90(6): 539-546, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37157143

RESUMO

BACKGROUND: There is a lack of convenient and accurate objective methods to evaluate the clinical efficacy of thigh liposuction. METHODS: This retrospective study involved the 3-dimensional images of 19 patients who underwent bilateral thigh liposuction. Data such as volume change and volume change rate before and after surgery, circumference change, and circumference change rate of 3 planes (upper, middle, and lower) were analyzed. The correlation between body mass index and volume change rate and between preoperative circumference and circumference change rate of different planes were determined. RESULTS: There were significant differences between the preoperative and postoperative volume and circumference of 3 planes of 19 patients (38 thighs). The rate of change in total volume (16.90 ± 5.55%) correlated with the circumference change rate at the top of the thigh. There was also a linear relationship between body mass index and volume change rate, but not between preoperative circumference and circumference change rate. CONCLUSIONS: Three-dimensional imaging technology can accurately quantify the volume and circumference change of the thigh to objectively evaluate the clinical efficacy of thigh liposuction.


Assuntos
Lipectomia , Coxa da Perna , Humanos , Coxa da Perna/cirurgia , Lipectomia/métodos , Estudos Retrospectivos , Índice de Massa Corporal , Resultado do Tratamento
12.
Artigo em Inglês | MEDLINE | ID: mdl-37030862

RESUMO

View missing and label missing are two challenging problems in the applications of multi-view multi-label classification scenery. In the past years, many efforts have been made to address the incomplete multi-view learning or incomplete multi-label learning problem. However, few works can simultaneously handle the challenging case with both the incomplete issues. In this article, we propose a new incomplete multi-view multi-label learning network to address this challenging issue. The proposed method is composed of four major parts: view-specific deep feature extraction network, weighted representation fusion module, classification module, and view-specific deep decoder network. By, respectively, integrating the view missing information and label missing information into the weighted fusion module and classification module, the proposed method can effectively reduce the negative influence caused by two such incomplete issues and sufficiently explore the available data and label information to obtain the most discriminative feature extractor and classifier. Furthermore, our method can be trained in both supervised and semi-supervised manners, which has important implications for flexible deployment. Experimental results on five benchmarks in supervised and semi-supervised cases demonstrate that the proposed method can greatly enhance the classification performance on the difficult incomplete multi-view multi-label classification tasks with missing labels and missing views.

13.
Biomed Pharmacother ; 162: 114403, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37003034

RESUMO

OBJECTIVES: In the field of orthopedics, osteonecrosis of the femoral head (ONFH) is a common and refractory condition sometimes known as "immortal cancer" due to its complicated etiology, difficult treatment, and high disability rate. This paper's main goal is to examine the most recent literature on the pro-apoptotic effects of traditional Chinese medicine TCM monomers or compounds on osteocytes and to provide a summary of the potential signal routes. METHODS: The last ten years' worth of literature on ONFH as well as the anti-ONFH effects of aqueous extracts and monomers from traditional Chinese medicine were compiled. CONCLUSIONS: When all the relevant signal pathways are considered, the key apoptotic routes include those mediated by the mitochondrial pathway, the MAPK signaling pathway, the PI3K/Akt signaling pathway, the Wnt/-catenin signaling pathway, the HIF-1 signaling network, etc. As a result, we anticipate that this study will shed light on the value of TCM and its constituent parts for treating ONFH by inducing apoptosis in osteocytes and offer some guidance for the future development of innovative medications as anti-ONFH medications in clinical settings.


Assuntos
Necrose da Cabeça do Fêmur , Osteonecrose , Humanos , Osteócitos/metabolismo , Cabeça do Fêmur , Fosfatidilinositol 3-Quinases/metabolismo , Osteonecrose/metabolismo , Necrose da Cabeça do Fêmur/metabolismo , Via de Sinalização Wnt , Apoptose
14.
Sensors (Basel) ; 23(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36850419

RESUMO

High-resolution image transmission is required in safety helmet detection problems in the construction industry, which makes it difficult for existing image detection methods to achieve high-speed detection. To overcome this problem, a novel super-resolution (SR) reconstruction module is designed to improve the resolution of images before the detection module. In the super-resolution reconstruction module, the multichannel attention mechanism module is used to improve the breadth of feature capture. Furthermore, a novel CSP (Cross Stage Partial) module of YOLO (You Only Look Once) v5 is presented to reduce information loss and gradient confusion. Experiments are performed to validate the proposed algorithm. The PSNR (peak signal-to-noise ratio) of the proposed module is 29.420, and the SSIM (structural similarity) reaches 0.855. These results show that the proposed model works well for safety helmet detection in construction industries.

15.
Curr Probl Cardiol ; 48(3): 101539, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36528207

RESUMO

Heart failure (HF) and chronic obstructive pulmonary disease (COPD) are closely related in clinical practice. This study aimed to investigate the co-genetic characteristics and potential molecular mechanisms of HF and COPD. HF and COPD datasets were downloaded from gene expression omnibus database. After identifying common differentially expressed genes (DEGs), the functional analysis highlighted the critical role of extracellular matrix and ribosomal signaling pathways in both diseases. In addition, GeneMANIA's results suggested that the 2 diseases were related to immune infiltration, and CIBERSORT suggested the role of macrophages. We also discovered 4 TFs and 1408 miRNAs linked to both diseases, and salbutamol may positively affect them.


Assuntos
Insuficiência Cardíaca , MicroRNAs , Doença Pulmonar Obstrutiva Crônica , Humanos , Albuterol/uso terapêutico , Biologia Computacional , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/imunologia , MicroRNAs/genética , MicroRNAs/imunologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/imunologia
16.
Cogn Neurodyn ; 16(6): 1471-1483, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36408069

RESUMO

This brief presents the finite-time stabilization and fixed-time stabilization of multiple memristor-based neural networks (MMNNs) with nonlinear coupling. Under the retarded memristive theory, the generalized Lyapunov functional method, extended Filippov-framework and Laplacian matrix theory, we can realize both the finite-time stabilization and fixed-time stabilization problem of MMNNs by designing novel state-feedback controller and the corresponding adaptive controller with regulate parameters. Moreover, we assess the bounds of settling time for the both two kinds of stabilization respectively, and we deeply analyze the influence of initial desiring values and the linear growth condition of the controller on the system. Finally, the benefits of the proposed approach and the experimental analysis are demonstrated by numerical examples.

17.
Front Psychol ; 13: 919254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795447

RESUMO

The pandemic has impacted various industries, including the sports industry. However, corporate social responsibility (CSR) can mitigate the adverse effects of the crisis and promote the sports industry. To analyze the effect of CSR, the study examined the impact of perceived corporate social responsibility on injury prevention expectation, injury risk perception, and health up-gradation with the mediation of sports safety measures. There are 259 sportsmen of local sports bodies provided the data through a self-administered survey. Data analysis was conducted through Smart-PLS and SEM techniques. The outcome of the analysis showed that perceived corporate social responsibility leads to injury prevention expectation, injury risk perception, and health up-gradation. Also, the study found that sports safety measure mediates the relationship between perceived corporate social responsibility and injury prevention expectation, between perceived corporate social responsibility and injury risk perception, and between perceived corporate social responsibility and health up-gradation among sportsmen of local sports bodies. The theoretical implications were presented related to the significance of CSR and sports safety measure and their impact on sportsmen injury prevention expectation, health, and risk perception. The practical implications were related to the management of local sports bodies and how they can induce CSR initiatives and programs. Some limitations related to sample size, incorporating other variables, examining the model in other contexts, and using different study designs, have also been mentioned in the study.

19.
J Am Chem Soc ; 144(18): 8204-8213, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35471968

RESUMO

Aqueous-phase oxygen evolution reaction (OER) is the bottleneck of water splitting. The formation of the O-O bond involves the generation of paramagnetic oxygen molecules from the diamagnetic hydroxides. The spin configurations might play an important role in aqueous-phase molecular electrocatalysis. However, spintronic electrocatalysis is almost an uncultivated land for the exploration of the oxygen molecular catalysis process. Herein, we present a novel magnetic FeIII site spin-splitting strategy, wherein the electronic structure and spin states of the FeIII sites are effectively induced and optimized by the Jahn-Teller effect of Cu2+. The theoretical calculations and operando attenuated total reflectance-infrared Fourier transform infrared (ATR FT-IR) reveal the facilitation for the O-O bond formation, which accelerates the production of O2 from OH- and improves the OER activity. The Cu1-Ni6Fe2-LDH catalyst exhibits a low overpotential of 210 mV at 10 mA cm-2 and a low Tafel slope (33.7 mV dec-1), better than those of the initial Cu0-Ni6Fe2-LDHs (278 mV, 101.6 mV dec-1). With the Cu2+ regulation, we have realized the transformation of NiFe-LDHs from ferrimagnets to ferromagnets and showcase that the OER performance of Cu-NiFe-LDHs significantly increases compared with that of NiFe-LDHs under the effect of a magnetic field for the first time. The magnetic-field-assisted Cu1-Ni6Fe2-LDHs provide an ultralow overpotential of 180 mV at 10 mA cm-2, which is currently one of the best OER performances. The combination of the magnetic field and spin configuration provides new principles for the development of high-performance catalysts and understandings of the catalytic mechanism from the spintronic level.

20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(1): 75-83, 2022 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-35231968

RESUMO

Lower limb ankle exoskeletons have been used to improve walking efficiency and assist the elderly and patients with motor dysfunction in daily activities or rehabilitation training, while the assistance patterns may influence the wearer's lower limb muscle activities and coordination patterns. In this paper, we aim to evaluate the effects of different ankle exoskeleton assistance patterns on wearer's lower limb muscle activities and coordination patterns. A tethered ankle exoskeleton with nine assistance patterns that combined with differenet actuation timing values and torque magnitude levels was used to assist human walking. Lower limb muscle surface electromyography signals were collected from 7 participants walking on a treadmill at a speed of 1.25 m/s. Results showed that the soleus muscle activities were significantly reduced during assisted walking. In one assistance pattern with peak time in 49% of stride and peak torque at 0.7 N·m/kg, the soleus muscle activity was decreased by (38.5 ± 10.8)%. Compared with actuation timing, the assistance torque magnitude had a more significant influence on soleus muscle activity. In all assistance patterns, the eight lower limb muscle activities could be decomposed to five basic muscle synergies. The muscle synergies changed little under assistance with appropriate actuation timing and torque magnitude. Besides, co-contraction indexs of soleus and tibialis anterior, rectus femoris and semitendinosus under exoskeleton assistance were higher than normal walking. Our results are expected to help to understand how healthy wearers adjust their neuromuscular control mechanisms to adapt to different exoskeleton assistance patterns, and provide reference to select appropriate assistance to improve walking efficiency.


Assuntos
Exoesqueleto Energizado , Idoso , Tornozelo/fisiologia , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos/fisiologia , Eletromiografia , Marcha/fisiologia , Humanos , Contração Muscular , Músculo Esquelético/fisiologia , Caminhada/fisiologia
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