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1.
BMC Public Health ; 24(1): 776, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38475781

RESUMO

BACKGROUND: The elderly, especially those with physical disabilities, often encounter barriers that prevent them from accessing outdoor activities. Their perceptions of the convenience of accessing outdoor activities may be influenced by various factors including their health, the social context, and/or planned behavior. This study aimed to develop predictive models that identify the principal determinants of perceived convenience among this demographic, and it also examined the disparities observed between genders. METHODS: This was a cross-sectional survey of 1216 community-dwelling older people with physical disabilities in rural China. Grounded on the rehabilitation concepts and the theory of planned behavior, structural equation models integrated health and social behavior factors were constructed to predict perceived convenience of accessing outdoor activities. The standardized coefficients explained the contributions of various factors to the variance. RESULTS: The final structural models demonstrated good fit for both female and male participants. Perceptions of the convenience of accessing outdoor activities among both women and men were directly impacted by their physical functioning and their intention to participate, and indirectly by medical expenditure, subjective norms, pain, and role limitation in emotional interactions. Positive mental health was more influential for women, while men were more influenced by subjective norms. CONCLUSIONS: Structural equation models have effectively predicted the self-reported convenience of accessing outdoor activities, underscoring the importance of functional and behavioral rehabilitation. Furthermore, gender-sensitive rehabilitation programs are advised to promote engagement in outdoor activities among elderly individuals with physical disabilities.


Assuntos
Pessoas com Deficiência , Intenção , Humanos , Masculino , Feminino , Idoso , Estudos Transversais , Pessoas com Deficiência/psicologia , Autorrelato , Modelos Teóricos , Inquéritos e Questionários
2.
Biomed Chromatogr ; 37(12): e5737, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37651996

RESUMO

Remibrutinib is a potent and highly selective covalent Bruton's tyrosine kinase inhibitor that is undergoing clinical development for the treatment of autoimmune diseases. The present study was undertaken to investigate the in vitro metabolism of remibrutinib and to propose its biotransformation pathways. The metabolites were generated by incubating remibrutinib (2 µm) with human and rat liver microsomes at 37°C for 30 min. Ultra-high-performance liquid chromatography combined with benchtop orbitrap high-resolution mass spectrometry was used to identify and characterize the metabolites of remibrutinib. Compound Discoverer software was employed to process the acquired data. In rat liver microsomes, a total of 18 metabolites have been identified and characterized among which three (M8, M12 and M13) were identified as the most abundant metabolites. In human liver microsomes, a total of 16 metabolites have been identified, and M8 and M12 were identified as the predominant metabolites. All the metabolites were nicotinamide adenine dinucleotide phosphate dependent. The major metabolic changes were found to be oxygenation, dealkylation, demethylation, epoxidation and hydrolysis. The present study comprehensively reports the in vitro metabolism of remibrutinib mentioning 20 metabolites. These findings will help investigation of remibrutinib disposition and safety evaluation.


Assuntos
Microssomos Hepáticos , Ratos , Humanos , Animais , Microssomos Hepáticos/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodos
3.
BMC Surg ; 23(1): 231, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37568142

RESUMO

INTRODUCTION: How to reconstruct the damaged fingertip is a clinical problem. Our team propose the theory of equivalent design and use the mini toenail flap pedicled with the hallux transverse artery and toe pulp vein transplantation technique to reconstruct Allen's type II fingertip injury. Thus, we perform the retrospective study to evaluate the effects of this technique on fingertip injury. MATERIALS AND METHODS: A retrospective analysis was performed on 56 patients admitted to our hospital from January 2015 to January 2020 who used equivalently designed miniature hallux toenail flaps for the plastic repair of fingertip damage. We recorded the size of the miniature hallux toenail flap, operation time, intraoperative blood loss, and complications and calculated the survival rate of the transplanted miniature hallux toenail flap. During routine follow-up after surgery, we recorded nail growth time and observed finger appearance. At the last time of follow-up, we recorded Semmes-Weinstein evaluating tactile sensation and Two-point discrimination testing (TPD). The efficacy was evaluated by Zook score evaluation. RESULTS: The size of the mini hallux toenail flap was 0.71 cm × 1.22 cm to 0.88 cm × 1.71 cm. The operation time was (3.54 ± 0.58) hours, the intraoperative blood loss was (20.66 ± 4.87) ml, and the survival rate of mini hallux toenail flaps was 100%. The postoperative follow-up time was (30.82 ± 11.21) months, and the total nail growth time was (9.68 ± 2.11) months. The average tactile sensation evaluated by the Semmes-Weinstein test was (0.32 ± 0.14) g, and the average TPD was (7.33 ± 1.02) mm. According to Zook score, the curative effect of fifty-six cases were all excellent or good with 100% excellent and good rate, and all patients had beautiful appearances and good function of damaged fingertips. CONCLUSIONS: Based on the equivalent design theory, the mini hallux toenail flap pedicled with the hallux transverse artery and toe pulp vein transplantation technique is an effective method to reconstruct Allen's type II fingertip injury with a beautiful appearance and good function. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Assuntos
Traumatismos dos Dedos , Hallux , Procedimentos de Cirurgia Plástica , Humanos , Hallux/cirurgia , Hallux/lesões , Unhas/cirurgia , Unhas/lesões , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Transplante de Pele/métodos , Traumatismos dos Dedos/cirurgia , Artérias/cirurgia , Resultado do Tratamento
4.
Plant J ; 104(5): 1285-1300, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32996179

RESUMO

An evaluation of combining ability can facilitate the selection of suitable parents and superior F1 hybrids for hybrid cotton breeding, although the molecular genetic basis of combining ability has not been fully characterized. In the present study, 282 female parents were crossed with four male parents in accordance with the North Carolina II mating scheme to generate 1128 hybrids. The parental lines were genotyped based on restriction site-associated DNA sequencing and 306 814 filtered single nucleotide polymorphisms were used for genome-wide association analysis involving the phenotypes, general combining ability (GCA) values, and specific combining ability values of eight fiber quality- and yield-related traits. The main results were: (i) all parents could be clustered into five subgroups based on population structure analyses and the GCA performance of the female parents had significant differences between subgroups; (ii) 20 accessions with a top 5% GCA value for more than one trait were identified as elite parents for hybrid cotton breeding; (iii) 120 significant single nucleotide polymorphisms, clustered into 66 quantitative trait loci, such as the previously reported Gh_A07G1769 and GhHOX3 genes, were found to be significantly associated with GCA; and (iv) identified quantitative trait loci for GCA had a cumulative effect on GCA of the accessions. Overall, our results suggest that pyramiding the favorable loci for GCA may improve the efficiency of hybrid cotton breeding.


Assuntos
Fibra de Algodão , Gossypium/genética , Polimorfismo de Nucleotídeo Único , Quimera , Regulação da Expressão Gênica de Plantas , Pleiotropia Genética , Genética Populacional , Genoma de Planta , Estudo de Associação Genômica Ampla , Gossypium/fisiologia , Haplótipos , Melhoramento Vegetal , Locos de Características Quantitativas
5.
Physiol Mol Biol Plants ; 27(12): 2849-2858, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35035140

RESUMO

Drought stress substantially influences the growth and development of many crops. The present study was conducted to investigate the effects of exogenous selenium on the growth, photosynthesis and antioxidant response of fragrant rice seedlings under drought stress. In a pot experiment, fragrant rice seedlings were subjected to drought stress (soil water potential was controlled at - 0.025 ± 5 MPa) and foliar application of selenium (Se) at 0, 10, 30, and 50 µmol L-1. Rice seedlings not exposed to drought stress and Se were used as control. Exposure of fragrant rice seedlings to drought stress resulted in significant (P < 0.05) decrease in fresh weight, dry weight, plant height and stem diameter relative to the control. Total chlorophyll, chlorophyll a, chlorophyll b and carotenoid were 20.54-27.24%, 20.82-26.83%, 19.45-29.07% and 21.49-29.17% lower with drought stress treatment compared to CK. Drought stress also significantly (P < 0.05) decreased net photosynthetic rate and soluble protein content. However, Se treatments (30 and 50 µmol L-1) substantially improved fresh weight and dry weight of fragrant rice seedlings under drought stress. Net photosynthetic rate, activities of antioxidant enzymes (GPX, SOD and CAT) and soluble protein content in rice seedlings under drought stress improved due to Se treatment. Higher transcript levels of antioxidant-related genes (GPX1, GPX4, CATA and CATC) were also observed with Se treatment.

6.
Chemphyschem ; 21(9): 908-915, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150322

RESUMO

For all-polymer solar cells which are composed of polymer donors and polymer acceptors, the effect of alkyl side chains on photovoltaic performance is a matter of some debate, and this effect remains difficult to forecast. In this concise contribution, we demonstrate that three alkyls namely branched alkyl 2-butyloctyl (2BO), long linear alkyl n-dodecyl (C12), and double-short linear alkyl n-hexyls (DC6) incorporated into the side chains of large bandgap polymer donor PBDT-TTz can induce considerable, of significance, and different electronic, optical, and morphological parameters. Systematic studies shed light on the critical role of the double-short linear alkyl n-hexyls (DC6) in (i) producing large ionization potential value, (ii) increasing propensity of the polymer to order along the π-stacking direction, (iii) generating polymer crystallites with more preferential "face-on" orientation, consequently, (iv) improvement of carriers transportation, (v) suppression of charge recombination, (vi) reduction of energy loss in all-polymer devices. In parallel, we unearth that the PBDT-TTz with double-short linear alkyl n-hexyls (DC6) represents the highest efficiency of 8.3 %, whereas, the other two PBDT-TTz analogues (2BO, C12) yield efficiencies of less than 3 % in optimized all-polymer solar cells. Though branched or long linear alkyl side chains (2BO, C12) have been applied to provide the solution processability of conjugated polymers, motifs bearing multiple short linear alkyl substituents (DC6) are proved critical to the development of high performing polymers.

7.
Bioorg Med Chem Lett ; 29(4): 681-683, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30611616

RESUMO

Lysine specific demethylase (LSD1) plays a pivotal role in epigenetic modulation of gene expression. Abberrant expression of LSD1 was associated with the progress and oncogenesis of multiple human cancers. Herein, we report the preliminary anti-LSD1 evaluation of the synthetic vanadium (V) complexes. Among them, complex 2 showed a moderate inhibitory effect against LSD1 with IC50 value of 19.0 µM, as well as good selectivity over MAO-A/B. Complex 2 is the first vanadium based LSD1 inhibitor, which provides a novel scaffold for the development of LSD1 inhibitor.


Assuntos
Histona Desmetilases/antagonistas & inibidores , Bases de Schiff/química , Compostos de Vanádio/química , Humanos , Ligantes , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
8.
BMC Genomics ; 19(1): 776, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30373509

RESUMO

BACKGROUND: Heterosis, a multigenic complex trait extrapolated as sum total of many phenotypic features, is widely utilized phenomenon in agricultural crops for about a century. It is mainly focused on establishing vigorous cultivars with the fact that its deployment in crops necessitates the perspective of genomic impressions on prior selection for metric traits. In spite of extensive investigations, the actual mysterious genetic basis of heterosis is yet to unravel. Contemporary crop breeding is aimed at enhanced crop production overcoming former achievements. Leading cotton improvement programs remained handicapped to attain significant accomplishments. RESULTS: In mentioned context, a comprehensive project was designed involving a large collection of cotton accessions including 284 lines, 5 testers along with their respective F1 hybrids derived from Line × Tester mating design were evaluated under 10 diverse environments. Heterosis, GCA and SCA were estimated from morphological and fiber quality traits by L × T analysis. For the exploration of elite marker alleles related to heterosis and to provide the material carrying such multiple alleles the mentioned three dependent variables along with trait phenotype values were executed for association study aided by microsatellites in mixed linear model based on population structure and linkage disequilibrium analysis. Highly significant 46 microsatellites were discovered in association with the fiber and yield related traits under study. It was observed that two-thirds of the highly significant associated microsatellites related to fiber quality were distributed on D sub-genome, including some with pleiotropic effect. Newly discovered 32 hQTLs related to fiber quality traits are one of prominent findings from current study. A set of 96 exclusively favorable alleles were discovered and C tester (A971Bt) posited a major contributor of these alleles primarily associated with fiber quality. CONCLUSIONS: Hence, to uncover hidden facts lying within heterosis phenomenon, discovery of additional hQTLs is required to improve fibre quality. To grab prominent improvement in influenced fiber quality and yield traits, we suggest the A971 Bt cotton cultivar as fundamental element in advance breeding programs as a parent of choice.


Assuntos
Heterogeneidade Genética , Gossypium/genética , Vigor Híbrido , Estudos de Associação Genética , Genótipo , Repetições de Microssatélites , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas , Característica Quantitativa Herdável
9.
Sensors (Basel) ; 18(4)2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29596330

RESUMO

This study proposes two models for precise time transfer using the BeiDou Navigation Satellite System triple-frequency signals: ionosphere-free (IF) combined precise point positioning (PPP) model with two dual-frequency combinations (IF-PPP1) and ionosphere-free combined PPP model with a single triple-frequency combination (IF-PPP2). A dataset with a short baseline (with a common external time frequency) and a long baseline are used for performance assessments. The results show that IF-PPP1 and IF-PPP2 models can both be used for precise time transfer using BeiDou Navigation Satellite System (BDS) triple-frequency signals, and the accuracy and stability of time transfer is the same in both cases, except for a constant system bias caused by the hardware delay of different frequencies, which can be removed by the parameter estimation and prediction with long time datasets or by a priori calibration.

10.
Mol Genet Genomics ; 292(6): 1267-1280, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28748394

RESUMO

Fiber yield and quality are the most important traits for Upland cotton (Gossypium hirsutum L.). Identifying high yield and good fiber quality genes are the prime concern of researchers in cotton breeding. Association mapping offers an alternative and powerful method for detecting those complex agronomic traits. In this study, 198 simple sequence repeats (SSRs) were used to screen markers associated with fiber yield and quality traits with 302 elite Upland cotton accessions that were evaluated in 12 locations representing the Yellow River and Yangtze River cotton growing regions of China. Three subpopulations were found after the estimation of population structure. The pair-wise kinship values varied from 0 to 0.867. Only 1.59% of the total marker locus pairs showed significant linkage disequilibrium (LD, p < 0.001). The genome-wide LD decayed within the genetic distance of ~30 to 32 cM at r 2 = 0.1, and decreased to ~1 to 2 cM at r 2 = 0.2, indicating the potential for association mapping. Analysis based on a mixed linear model detected 57 significant (p < 0.01) marker-trait associations, including seven associations for fiber length, ten for fiber micronaire, nine for fiber strength, eight for fiber elongation, five for fiber uniformity index, five for fiber uniformity ratio, six for boll weight and seven for lint percent, for a total of 35 SSR markers, of which 11 markers were associated with more than one trait. Among marker-trait associations, 24 associations coincided with the previously reported quantitative trait loci (QTLs), the remainder were newly identified QTLs/genes. The QTLs identified in this study will potentially facilitate improvement of fiber yield and quality in the future cotton molecular breeding programs.


Assuntos
Fibra de Algodão , Gossypium/genética , Desequilíbrio de Ligação , Locos de Características Quantitativas
11.
Sensors (Basel) ; 17(3)2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28273814

RESUMO

In this study, a unified model for BeiDou Navigation Satellite System (BDS) wide area and local area augmentation positioning based on raw observations has been proposed. Applying this model, both the Real-Time Kinematic (RTK) and Precise Point Positioning (PPP) service can be realized by performing different corrections at the user end. This algorithm was assessed and validated with the BDS data collected at four regional stations from Day of Year (DOY) 080 to 083 of 2016. When the users are located within the local reference network, the fast and high precision RTK service can be achieved using the regional observation corrections, revealing a convergence time of about several seconds and a precision of about 2-3 cm. For the users out of the regional reference network, the global broadcast State-Space Represented (SSR) corrections can be utilized to realize the global PPP service which shows a convergence time of about 25 min for achieving an accuracy of 10 cm. With this unified model, it can not only integrate the Network RTK (NRTK) and PPP into a seamless positioning service, but also recover the ionosphere Vertical Total Electronic Content (VTEC) and Differential Code Bias (DCB) values that are useful for the ionosphere monitoring and modeling.

12.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(5): 557-560, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38845507

RESUMO

Endothelial cells have important physiological functions and regulatory effects related to the occurrence and development of various diseases. Piezo1 is a mechanically sensitive ion channel protein, which is widely distributed in various tissues of the body and participates in the occurrence and development of various diseases. Piezo1 is highly expressed in endothelial cells and plays an important regulatory role in endothelial cell function. This article reviews the structure and function of Piezo1, the physiological function and pathological damage mechanism of endothelial cells, and the role of endothelial cell Piezo1 in various diseases, in order to understand the function and regulation mechanism of endothelial cell Piezo1, and provide new targets and strategies for the treatment of related diseases.


Assuntos
Células Endoteliais , Canais Iônicos , Canais Iônicos/metabolismo , Canais Iônicos/fisiologia , Humanos , Células Endoteliais/metabolismo
13.
Front Immunol ; 15: 1281263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38487535

RESUMO

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Due to its high infectivity, the pandemic has rapidly spread and become a global health crisis. Emerging evidence indicates that endothelial dysfunction may play a central role in the multiorgan injuries associated with COVID-19. Therefore, there is an urgent need to discover and validate novel therapeutic strategies targeting endothelial cells. PIEZO1, a mechanosensitive (MS) ion channel highly expressed in the blood vessels of various tissues, has garnered increasing attention for its potential involvement in the regulation of inflammation, thrombosis, and endothelial integrity. This review aims to provide a novel perspective on the potential role of PIEZO1 as a promising target for mitigating COVID-19-associated endothelial dysfunction.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Células Endoteliais , Inflamação , Endotélio , Canais Iônicos
14.
Front Immunol ; 15: 1328667, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576606

RESUMO

Sepsis remains a significant cause of mortality and morbidity worldwide, with limited effective treatment options. The T-cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) has emerged as a potential therapeutic target in various immune-related disorders. This narrative review aims to explore the role of TIM-3 in sepsis and evaluate its potential as a promising target for immunotherapy. We discuss the dynamic expression patterns of TIM-3 during sepsis and its involvement in regulating immune responses. Furthermore, we examine the preclinical studies investigating the regulation of TIM-3 signaling pathways in septic models, highlighting the potential therapeutic benefits and challenges associated with targeting TIM-3. Overall, this review emphasizes the importance of TIM-3 in sepsis pathogenesis and underscores the promising prospects of TIM-3-based immunotherapy as a potential strategy to combat this life-threatening condition.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Sepse , Humanos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Imunoterapia , Sepse/terapia , Transdução de Sinais
15.
IEEE Trans Cybern ; 53(2): 793-805, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35316207

RESUMO

Small sample size leads to low accuracy and poor generalization of industrial fault diagnosis modeling. Domain adaptation (DA) attempts to enhance small samples by transferring samples in other similar domains, but it has limited application in industrial fault diagnosis, since the differences in working conditions lead to large variations of fault samples. To address the above issues, this article proposes a heterogeneous sample enhancement network with lifelong learning (HSELL-Net). First, a heterogeneous DA subnet (HDA-subnet) is presented, in which the designed heterogeneous supporting domain ensures dimension alignment and the designed distribution jointly matching improves the performance of distribution matching; thus, fault samples from other working conditions can be employed to reliably enhance small samples. Second, a lifelong learning subnet (LL-subnet) is designed, in which the proposed Admixup and shared knowledge repository enable incremental samples to further enhance small samples without retraining the network. The two subnets are mutually embedded and reinforced to enhance the number and types of small samples; thus, the accuracy and generalization of fault diagnosis under industrial small samples are improved. Finally, benchmark simulated experiments and real-world application experiments are conducted to evaluate the proposed method. Experimental results show the HSELL-Net outperforms the existing works under industrial small samples.

16.
ISA Trans ; 142: 299-309, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37679275

RESUMO

This paper is devoted to the topology-based dynamic event-triggered leader-following consensus issue of general linear multi-agent systems under switching topological structures. The novel topology-based distributed dynamic event-triggered rule is formed, in which a topology-based dynamic auxiliary variable is introduced to reduce the conservatism and save resources. Under novel triggering rules, topology-based distributed event-triggered controllers are constructed. Different control gains are designed for different topological structures. Compared with existing works, conservatism is further reduced. Then the leader-following consensus is achieved with a global exponential convergence rate. Moreover, the average dwell time method is adopted to relax restrictions on the switching speed of topological structures and an original analytical thought is put forward to rule out the Zeno phenomenon concisely and clearly. Finally, two numerical examples and a realistic mass-spring system are utilized to verify the feasibility and superiority of the proposed theory.

17.
Anticancer Agents Med Chem ; 23(9): 999-1012, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36683373

RESUMO

Cancer drug resistance has always been a serious issue regarding cancer research and therapy. Different cancers undergo different mutations, which may cause suppression of tumor suppressor genes, inhibition of apoptosis, stimulation of drug resistance mediators, and exhaustion of the immune system. The modulation of pro-death and survival-related mediators is an intriguing strategy for cancer therapy. Several nature-derived molecules, e.g., quercetin, have shown interesting properties against cancer through the modulation of apoptosis and autophagy mediators. Such molecules, e.g., quercetin, have been shown to stimulate apoptosis and other types of cell death pathways in cancers via the modulation of ROS metabolism. Quercetin may affect immune system function and trigger the expression and activity of tumor suppressor genes. Furthermore, it may suppress certain multidrug resistance mechanisms in cancer cells. This paper aims to review the effects of quercetin on various cell death mechanisms such as apoptosis, autophagic cell death, senescence, ferroptosis, and others.


Assuntos
Neoplasias , Quercetina , Humanos , Quercetina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Morte Celular , Neoplasias/tratamento farmacológico , Apoptose , Autofagia , Linhagem Celular Tumoral
18.
Artigo em Inglês | MEDLINE | ID: mdl-37436860

RESUMO

Automatic defect detection plays an important role in industrial production. Deep learning-based defect detection methods have achieved promising results. However, there are still two challenges in the current defect detection methods: 1) high-precision detection of weak defects is limited and 2) it is difficult for current defect detection methods to achieve satisfactory results dealing with strong background noise. This article proposes a dynamic weights-based wavelet attention neural network (DWWA-Net) to address these issues, which can enhance the feature representation of defects and simultaneously denoise the image, thereby improving the detection accuracy of weak defects and defects under strong background noise. First, wavelet neural networks and dynamic wavelet convolution networks (DWCNets) are presented, which can effectively filter background noise and improve model convergence. Second, a multiview attention module is designed, which can direct the network attention toward potential targets, thereby guaranteeing the accuracy for detecting weak defects. Finally, a feature feedback module is proposed, which can enhance the feature information of defects to further improve the weak defect detection accuracy. The DWWA-Net can be used for defect detection in multiple industrial fields. Experiment results illustrate that the proposed method outperforms the state-of-the-art methods (mean precision: GC10-DET: 6.0%; NEU: 4.3%). The code is made in https://github.com/781458112/DWWA.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38048569

RESUMO

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) are favorable for all-solid-state lithium metal batteries (ASSLBs) to ensure safety and enhance energy density. However, their narrow work windows and unstable electrode/electrolyte interfaces hinder their practical application in high-voltage ASSLBs. Although introducing additives in SPEs has been proven to be effective to address the above issues, it could hardly optimize both cathode and anode interfaces by an individual additive. Herein, heterogeneously double-layer SPEs are constructed with two typical additives (LiPO2F2 and LiFSI), which are used to modify the LiNi0.6Co0.2Mn0.2O2 (NCM)-cathode/electrolyte interface (CEI) and lithium-anode/solid electrolyte interface (SEI), and further understand their respective mechanism in enhancing the capacity and cycling stability of ASSLBs. Specifically, LiPO2F2 not only leads to a uniform CEI layer to prevent the oxidation decomposition of PEO and LiTFSI but also ensures fast Li+ diffusion at high voltage (>3.9 V), improving the rate performances and life spans of the cells. The LiFSI contributes to a stable SEI layer with rich LiF, suppressing the growth of lithium dendrites and maximizing the specific capacity for ASSLBs. Integrating the advantages of the two functional molecules, the optimized ASSLB displays an excellent capacity of 141.4 mAh g-1 at 1C and an outstanding capacity retention of 81.6% after 400 cycles when using the NCM cathode, even reaching 154.2 mAh g-1 at 0.1 mA cm-2 with a high mass loading (6.4 mg cm-2). Additionally, the bilayer SPEs also match well with a LiFePO4 electrode with a high mass loading of 11.0 mg cm-2, displaying a high capacity of 155.7 mAh g-1 at 0.1 mA cm-2.

20.
Materials (Basel) ; 16(13)2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37445096

RESUMO

To improve the heat resistance of titanium alloys, the effects of Y content on the precipitation behavior, oxidation resistance and high-temperature mechanical properties of as-cast Ti-5Al-2.75Sn-3Zr-1.5Mo-0.45Si-1W-2Nb-xY (x = 0.1, 0.2, 0.4) alloys were systematically investigated. The microstructures, phase evolution and oxidation scales were characterized by XRD, Laser Raman, XPS, SEM and TEM. The properties were studied by cyclic oxidation as well as room- and high-temperature tensile testing. The results show that the microstructures of the alloys are of the widmanstätten structure with typical basket weave features, and the prior ß grain size and α lamellar spacing are refined with the increase of Y content. The precipitates in the alloys mainly include Y2O3 and (TiZr)6Si3 silicide phases. The Y2O3 phase has specific orientation relationships with the α-Ti phase: (002)Y2O3 // (1¯1¯20)α-Ti, [110]Y2O3 // [4¯401]α-Ti. (TiZr)6Si3 has an orientation relationship with the ß-Ti phase: (022¯1¯)(TiZr)6Si3 // (011)ß-Ti, [1¯21¯6](TiZr)6Si3 // [044¯]ß-Ti. The 0.1 wt.% Y composition alloy has the best high-temperature oxidation resistance at different temperatures. The oxidation behaviors of the alloys follow the linear-parabolic law, and the oxidation products of the alloys are composed of rutile-TiO2, anatase-TiO2, Y2O3 and Al2O3. The room-temperature and 700 °C UTS of the alloys decreases first and then increases with the increase of Y content; the 0.1 wt.% Y composition alloy has the best room-temperature mechanical properties with a UTS of 1012 MPa and elongation of 1.0%. The 700 °C UTS and elongation of the alloy with 0.1 wt.% Y is 694 MPa and 9.8%, showing an optimal comprehensive performance. The UTS and elongation of the alloys at 750 °C increase first and then decrease with the increase of Y content. The optimal UTS and elongation of the alloy is 556 MPa and 10.1% obtained in 0.2 wt.% Y composition alloy. The cleavage and dimples fractures are the primary fracture mode for the room- and high-temperature tensile fracture, respectively.

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