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Most studies investigate the cyclable capacity fading mechanism of Li-rich layered oxides (LLOs) from the microscopic structure level, lacking discussions about how the structure degradation influences the performance of the pouch cell precisely and quantitatively. Based on the analysis of the evolution of key parameters during the whole cycling period, a new transition-type fading mechanism is proposed. From the early-to-middle stage of the cycling period, polarization increases, most of which is interface-related, causing about 67% of the whole capacity loss. From the middle-to-late stage of the cycling period, active material losses turn out to be the dominating factor, inducing about 61% of the total capacity loss. Diffusion-related polarization, replacing the interface type, is responsible for most of the increased overpotential. Relative analysis confirms that during the early stage, the increase of the charge transfer resistance, induced by CEI (cathode electrolyte interface) growth and initial surface layered-structure degradation, is the main source of interface polarization. As the cycling evolves to the late stage, severe bulky structure degradation, including lattice-oxygen release, Li/Ni mixture and generation of a new spinel phase, turns out to be the major factor, causing further capacity fading.
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BACKGROUND: Wound treatment in emergency care requires the rapid assessment of wound size by medical staff. Limited medical resources and the empirical assessment of wounds can delay the treatment of patients, and manual contact measurement methods are often inaccurate and susceptible to wound infection. This study aimed to prepare an Automatic Wound Segmentation Assessment (AWSA) framework for real-time wound segmentation and automatic wound region estimation. METHODS: This method comprised a short-term dense concatenate classification network (STDC-Net) as the backbone, realizing a segmentation accuracy-prediction speed trade-off. A coordinated attention mechanism was introduced to further improve the network segmentation performance. A functional relationship model between prior graphics pixels and shooting heights was constructed to achieve wound area measurement. Finally, extensive experiments on two types of wound datasets were conducted. RESULTS: The experimental results showed that real-time AWSA outperformed state-of-the-art methods such as mAP, mIoU, recall, and dice score. The AUC value, which reflected the comprehensive segmentation ability, also reached the highest level of about 99.5%. The FPS values of our proposed segmentation method in the two datasets were 100.08 and 102.11, respectively, which were about 42% higher than those of the second-ranked method, reflecting better real-time performance. Moreover, real-time AWSA could automatically estimate the wound area in square centimeters with a relative error of only about 3.1%. CONCLUSION: The real-time AWSA method used the STDC-Net classification network as its backbone and improved the network processing speed while accurately segmenting the wound, realizing a segmentation accuracy-prediction speed trade-off.
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OBJECTIVE: Recently, some clinical studies have reported the use of an intramedullary nailing system for treating unstable femoral neck fractures or femoral neck fractures combined with femoral shaft fractures in young adults, and the results have indicated certain advantages. However, no study has investigated the mechanical properties of this method. We aimed to evaluate the mechanical stability and clinical efficacy of the Gamma nail combined with one cannulated compression screw (CCS) fixation for treating Pauwels type III femoral neck fracture in young and middle-aged adults. METHODS: This study consists of two parts: a clinical retrospective study and randomized controlled biomechanical test. Twelve adult cadaver femora were used to test and compare the biomechanical properties among three fixation methods: three parallel CCS (group A), Gamma nail (group B), and Gamma nail combined with one cannulated compression screw (group C). The single continuous compression test, cyclic load test, and ultimate vertical load test were used to evaluate the biomechanical performance of the three fixation methods. We also conducted a retrospective study of 31 patients with Pauwels type III femoral neck fractures, including 16 patients with fractures fixed with three parallel CCS (CCS group) and 15 patients with fractures fixed with Gamma nail combined with one CCS (Gamma nail + CCS group). The patients were followed up for at least 3 years, and all were evaluated for surgical time (from skin incision to closure), surgical blood loss, hospital stay, and the Harris hip score. RESULTS: In mechanical experiments, we have found that the mechanical advantages of Gamma nail fixation are not as good as those of conventional CCS fixation. However, the mechanical properties of Gamma nail fixation combined with one cannulated screw perpendicular to the fracture line are much better than those of Gamma nail fixation and CCS fixation. No significant difference was found in the incidence of femoral head necrosis and nonunion between the CCS and Gamma nail + CCS groups. Moreover, there was no statistically significant difference in the Harris hip scores between the two groups. One patient in the CCS group showed significant withdrawal of cannulated screws at 5 months after surgery, whereas in the Gamma nail + CCS group, all patients, including those with femoral neck necrosis, showed no loss of stability of the fixation. CONCLUSION: Among the two fixation methods evaluated in this study, Gamma nail combined with one CCS fixation showed better biomechanical properties and may reduce complications associated with unstable fixation devices.
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Fraturas do Colo Femoral , Fixação Interna de Fraturas , Pessoa de Meia-Idade , Adulto Jovem , Humanos , Fixação Interna de Fraturas/métodos , Seguimentos , Estudos Retrospectivos , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Resultado do TratamentoRESUMO
In this work, LaCoO3 and LaMnO3 perovskites with the higher specific surface area were synthesized using MOFs as precursor, then, the composite catalysts CeO2-LaCoxFeyO3 and CeO2-LaMnxFeyO3 were prepared by using CeO2 as support and Fe element doping LaCoO3 and LaMnO3, respectively. The as-prepared samples were characterized by XRD, SEM, XPS, H2-TPR, and N2 physisorption techniques. Subsequently, toluene was used as the probe molecule for volatile organic compounds (VOCs) to test the catalytic activity of these as-prepared catalysts. The results show that the initial reaction temperature for toluene oxidation on supported perovskite catalysts is lower. Among which, CeO2-LaCo0.25Fe0.75O3 (T90=215 °C, T90: the temperature corresponding to 90% conversion of toluene) and CeO2-LaMn0.25Fe0.75O3 (T90=205 °C) catalysts show the best catalytic performance. Therefore, the supported perovskite prepared in this study has the advantages of high specific surface area, abundant oxygen vacancies, and excellent oxygen mobility, which makes it exhibit better performance in VOCs catalytic oxidation.
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Óxidos , Tolueno , Oxirredução , OxigênioRESUMO
A three-dimensional g-C3N4/MWNTs/GO hybrid modified electrode was constructed as an electrochemical sensor for the simultaneous determination of ascorbic acid (AA), dopamine (DA) and uric acid (UA). Due to the high conductivity of MWCNTs and the strong synergy between g-C3N4 and GO, the combination of the three effectively improved the electrocatalytic activity of the modified electrode for the oxidation of AA, DA, and UA, and solved the problems such as overlapping anodic peaks. The electrochemical performance of the as-constructed sensor was investigated and optimized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The linear response range of AA, DA, and UA in the optimal condition was 0.2-7.5 mM, 2-100 µM, and 4-200 µM, respectively. The detection limits (S/N = 3) of AA, DA, and UA were 96, 0.22, and 1.36 µM, respectively. The recoveries of AA, DA and UA in serum samples from three groups were 92.82-106.50%, and the relative standard deviations were less than 2%. The results show that the as-constructed g-C3N4/MWNTs/GO modified electrode has the advantages of simplicity, high sensitivity and good selectivity, and can simultaneously determine AA, DA, and UA.
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Grafite , Ácido Úrico , Ácido Ascórbico , Dopamina , Técnicas Eletroquímicas/métodos , EletrodosRESUMO
Bone infection has always been the focus of orthopedic research. Mesenchymal stem cells (MSCs) are the natural progenitors of osteoblasts, and the process of osteogenesis is triggered in response to different signals from the extracellular matrix. MSCs exert important functions including secretion and immune regulation and also play a key role in bone regeneration. The biological behavior of MSCs in acute and chronic inflammation, especially the transformation between acute inflammation and chronic inflammation, has aroused great interest among researchers. This paper reviews the recent literature and summarizes the behavior and biological characteristics of MSCs in acute and chronic inflammation to stimulate further research on MSCs and treatment of bone diseases.
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Diferenciação Celular , Movimento Celular , Imunomodulação , Inflamação/fisiopatologia , Células-Tronco Mesenquimais/fisiologia , Osteogênese , Doença Aguda , Doenças Ósseas/fisiopatologia , Doença Crônica , Humanos , Infecções/fisiopatologia , Transdução de SinaisRESUMO
Background: Recent studies have suggested that proton pump inhibitors (PPIs) and histamine type 2 receptor antagonists (H2RAs) may increase the risk of fracture. We performed a meta-analysis to evaluate the risk of fracture with PPIs and H2RAs use in children and young adults. Methods: PubMed, EMBASE database, Cochrane Library, and Web of Science for relevant articles published before May 2021 were searched. We included all the observational studies reporting on the risk of fracture with acid-suppressive drug (PPIs and H2RAs) use in children and young adults. We calculated pooled risk ratios (RRs) for fracture using random-effects models and conducted subgroup analyses. Results: A total of six studies were included in our analysis. Pooled analysis of PPIs use showed significant risk for fracture (RR = 1.23; 95% CI, 1.12-1.34; I 2 = 79.3), but not significant for PPIs combined with H2RAs use (RR = 1.22; 95% CI, 0.94-1.60; I 2 = 44.0%), as well as for H2RAs use alone (RR = 1.08; 95% CI, 0.94-1.24; I 2 = 84.1%). Grouping of studies by region showed a significantly increased fracture risk with PPIs use in North America (RR = 1.24; 95% CI, 1.16-1.32; I 2 =0.0%) than in Europe (RR = 1.23; 95% CI, 1.00-1.52; I 2 = 94.6%) and Asia (RR = 1.10; 95% CI, 0.96-1.25). However, there was no significant association between the H2RAs use and the fracture risk in North America (RR = 1.08; 95% CI, 1.00-1.09; I 2 = 0.0%). Moreover, PPIs use showed an increased risk of fracture in women (RR = 1.13; 95% CI, 1.07-1.19; I 2 = 0.0%), whereas there was no significant association between the PPIs use and the risk of fracture in men (RR = 0.93; 95% CI, 0.66-1.31; I 2 = 0.0%). Conclusion: PPIs use alone could increase the risk of fracture in children and young adults, but not for PPIs combined with H2RAs use or H2RAs use alone. Clinicians should exercise caution when prescribing PPIs for patients.
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Background: Abnormal expression levels of microRNAs (miRNAs) were observed in ankylosing spondylitis (AS) in recent articles, suggesting that miRNAs may be used as biomarkers for AS diagnoses. In this paper, we conducted a meta-analysis to identify the overall diagnostic accuracy of miRNA biomarkers in AS patients. Methods: An extensive search was undertaken in PubMed, Embase, Cochrane databases, and Wan Fang database up to 30 December 2020 using the following key words: ("microRNAs" or "microRNA" or "miRNA" or "miR" or "RNA, Micro" or "Primary MicroRNA") and ("Spondylitis Ankylosing" or "Spondyloarthritis Ankylopoietica" or "Ankylosing Spondylarthritis" or "Ankylosing Spondylarthritides" or "Spondylarthritides Ankylosing" or "Ankylosing Spondylitis") and ("blood" or "serum" or "plasma"). Statistical evaluation of dysregulated miRNAs using the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the area under the curve (AUC). Results: Twenty-nine articles reporting on the miRNAs of AS were included. A total of 42 miRNAs were observed to be up-regulated and 45 miRNAs were down-regulated in the AS cases compared with the controls. Besides, 29 studies from nine articles were included in our meta-analysis. The pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0. 76 (95% CI, 0.70-0.81), 0.80 (95% CI, 0.74-0.85), 3.75 (95% CI, 2.82-5.01), 0.30 (95% CI, 0.24-0.39), 12.32 (95% CI, 7.65-19.83), 0.85 (95% CI, 0.81-0.88), respectively, suggesting a good diagnostic accuracy of miRNAs for AS. Conclusions: Circulating miRNAs are deregulated in AS patients. miRNAs may be used as a relatively non-invasive biomarkers for the detection of AS.
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Background: Osteomyelitis is an inflammatory process characterized by progressive bone destruction. Moreover, chronic bacterial osteomyelitis is regarded as a difficult-to-treat clinical entity due to its long-standing course and frequent infection recurrence. However, the role of genetic factors in the occurrence and development of bacterial osteomyelitis is poorly understood. Methods: We performed a systematic review to assess the frequency of individual alleles and genotypes of single-nucleotide polymorphisms (SNPs) among patients with bacterial osteomyelitis and healthy people to identify whether the SNPs are associated with the risk of developing bacterial osteomyelitis. Then, gene ontology and Kyoto Encyclopedia of Gene and Genomes analyses were performed to identify the potential biological effects of these genes on the pathogenesis of bacterial osteomyelitis. Result: Fourteen eligible studies containing 25 genes were analyzed. In this review, we discovered that the SNPs in IL1B, IL6, IL4, IL10, IL12B, IL1A, IFNG, TNF, PTGS2, CTSG, vitamin D receptor (VDR), MMP1, PLAT, and BAX increased the risk of bacterial osteomyelitis, whereas those in IL1RN and TLR2 could protect against osteomyelitis. The bioinformatic analysis indicated that these osteomyelitis-related genes were mainly enriched in inflammatory reaction pathways, suggesting that inflammation plays a vital role in the development of bacterial osteomyelitis. Furthermore, functional notation for 25 SNPs in 17 significant genes was performed using the RegulomeDB and NCBI databases. Four SNPs (rs1143627, rs16944, rs2430561, and rs2070874) had smaller scores from regulome analysis, implying significant biological function. Conclusion: We systematically summarized several SNPs linked to bacterial osteomyelitis and discovered that these gene polymorphisms could be a genetic factor for bacterial osteomyelitis. Moreover, further large-scale cohort studies are needed to enhance our comprehensive understanding of the development of osteomyelitis to provide earlier individualized preventions and interventions for patients with osteomyelitis in clinical practice.
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BACKGROUND: Acute compartment syndrome (ACS) is a potentially devastating condition. ACS is rare in the upper arm. CASE PRESENTATION: We report a case of acute compartment syndrome of the anterior compartment of the upper arm due to brachial muscle injury. The patient experienced abnormal progressive swelling and pain in his right upper arm, and passive pulling pain of the right wrist and right hand. It was highly suspected to be right upper arm compartment syndrome, and was confirmed by surgery. The patient transferred to the emergency operating room for fasciotomy that was performed under general anesthesia using the anterolateral approach. The brachial muscle was found to be heavily swollen and had the greatest tension. The brachial muscle fibers were split lengthwise, and a large amount of hematoma was cleared. The brachial muscles were injured and partly ruptured. After full decompression, a negative pressure drainage device was used to cover the wound in the first stage. Ten days after injury, the swelling of the affected limb subsided and the wound was sutured. The patient's limbs completely recovered to normal. The shoulder and elbow joints could move freely and the patient resumed normal farming work ability. CONCLUSION: Clinicians should fully recognize the fact that acute compartment syndrome can occur in the upper arm, rather than only the forearm and leg, and therefore avoid serious consequences caused by missed diagnosis and misdiagnosis.
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Braço , Síndromes Compartimentais , Síndromes Compartimentais/diagnóstico , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/cirurgia , Fasciotomia , Antebraço , Humanos , MúsculosRESUMO
BACKGROUND: Reconstruction of the coracoclavicular (CC) ligament using a single TightRope (ST) system has some complications. We attempted to use a double TightRope (DT) system to reduce complications and obtain the ideal therapeutic effect. PURPOSE: This investigation aimed to compare the ST and DT systems in terms of efficacy and safety in treating acromioclavicular (AC) joint dislocation. METHODS: Sixty-six cases of acute AC joint dislocation between January 2013 and January 2018 were retrospectively reviewed. All patients were divided into 2 groups based on treatment with the ST or DT system. Patients were evaluated radiologically and clinically using the Disability of Arm, Shoulder, and Hand, Constant, and visual analog scale scores as clinical outcome measures at 1 day, 3 weeks, 6 weeks, 3 months, 6 months, 1 year, and 2 years after surgery. The CC distance and displacement ratio were assessed radiologically. RESULTS: The mean follow-up period was 49 months. Satisfactory clinical outcomes were obtained after CC fixation in both groups. No intergroup difference was found regarding the visual analog scale (P = .80), Disability of Arm, Shoulder, and Hand (P = .42), or Constant score (P = .28) at 2 years. However, there was a significant difference in the displacement ratio at 6 weeks (P < .0001), 3 months (P < .0001), 6 months (P < .0001), 1 year (P < .0001), and 2 years (P < .0001) postoperatively between the 2 groups. There were 3 complications in the ST group, including 1 case of secondary coracoid fracture, 1 case of AC joint arthrosis combined with ossification of the CC ligaments, and 1 case of clavicular erosion. All complications occurred in the ST group. CONCLUSIONS: Both surgical methods are effective in treating AC joint dislocation, but the DT system is more reliable for reduction maintenance.
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Articulação Acromioclavicular , Luxações Articulares , Luxação do Ombro , Articulação Acromioclavicular/diagnóstico por imagem , Articulação Acromioclavicular/cirurgia , Clavícula , Humanos , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/cirurgia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Bone infection is difficult to cure, and relapse frequently occurs, which is a major treatment problem. One of the main reasons for the refractory and recurrent nature of bone infection is that bacteria, such as Staphylococcus aureus (S. aureus), can be internalized into osteoblasts after infecting bone tissue, thereby avoiding attack by the immune system and antibiotics. Understanding how bacteria (such as S. aureus) are internalized into osteoblasts is key to effective treatment. S. aureus is the most common pathogenic bacterium that causes bone infection. This paper reviews the literature, analyzes the specific process of osteoblastic S. aureus infection, and summarizes specific treatment strategies to improve bone infection treatment.
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Osteoblastos/microbiologia , Animais , Antibacterianos/uso terapêutico , Células Cultivadas , Humanos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/patogenicidadeRESUMO
Salinity is one of the major abiotic stress factors limiting rice production. Glabrousness is a trait of agronomic importance in rice (Oryza sativa L.). We previously found a single-gene recessive mutant sst, which displayed increased salt tolerance and glabrous leaf and glume without trichomes, and identified an SBP-box gene OsSPL10 as the candidate of the SST gene. In this study, OsSPL10-knockout and OsSPL10-overexpression mutants were created to check the function of the gene. The knockout mutants exhibited enhanced salt tolerance and glabrous leaves and glumes as expected, while the overexpression mutants showed opposite phenotypes, in which both salt sensitivity and trichome density on leaf and glume were increased. These results clearly confirmed that OsSPL10 is SST, and suggested that OsSPL10 controls the initiation rather than the elongation of trichomes. In addition, expression analysis indicated that OsSPL10 was preferentially expressed in young panicle and stem, and protein OsSPL10 was localized in nucleus. Taken together, OsSPL10 negatively controls salt tolerance but positively controls trichome formation in rice.
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Genes de Plantas , Oryza/genética , Oryza/fisiologia , Proteínas de Plantas/genética , Tolerância ao Sal/genética , Tricomas/crescimento & desenvolvimento , Sequência de Bases , Núcleo Celular/metabolismo , Edição de Genes , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/metabolismo , Mutação/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Tricomas/genéticaRESUMO
Shelterbelt system is one of the main components of cultivated slope land in rolling hill black soil region of Northeast China, which plays an important role in the control of gully erosion. Based on the Quickbird high-resolution remote sensing image and the digital elevation model (DEM), and combining with field survey data, this paper analyzed the effects of shelterbelt system in a small watershed of rolling hill black soil region in Heshan Farm of Heilongjiang Province on the control of gully erosion in the cultivated slope land, and put forward an optimized scheme for gully erosion control based on the features of gully erosion in the cultivated slope land and their relations with the distribution of the shelterbelt system. In the study area, the current distribution of the shelterbelt system promoted the occurrence and development of shallow gully and gully directly and indirectly. The proposed scheme for optimizing the distribution of the present shelterbelts included the adjustment of the direction of the shelterbelt perpendicular to the aspect of slope, the enhancement of the maintenance and regeneration of the shelterbelts to reduce the gaps of the shelterbelts, the increase of the shelterbelt number, and the decrease of the distances between shelterbelts. A method for calculating the shelterbelt number and the distances between the shelterbelts was also given. This study could provide scientific basis for the gully erosion control and the shelterbelts programming in the cultivated slope land of rolling hill black soil region.