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The application of 2024 aluminum alloy (comprising aluminum, copper, and magnesium) in the aerospace industry is extensive, particularly in the manufacture of seats. However, this alloy faces challenges during laser powder bed fusion (PBF-LB/M) processing, which often leads to solidification and cracking issues. To address these challenges, LaB6 nanoparticles have been investigated as potential grain refiners. This study systematically examined the impact of adding different amounts of LaB6 nanoparticles (ranging from 0.0 to 1.0 wt.%) on the microstructure, phase composition, grain size, and mechanical properties of the composite material. The results demonstrate that the addition of 0.5 wt.% LaB6 significantly reduces the average grain size from 10.3 µm to 9 µm, leading to a significant grain refinement effect. Furthermore, the tensile strength and fracture strain of the LaB6-modified A2024 alloy reach 251 ± 2 MPa and 1.58 ± 0.12%, respectively. These findings indicate that the addition of appropriate amounts of LaB6 nanoparticles can effectively refine the grains of 2024 aluminum alloy, thereby enhancing its mechanical properties. This discovery provides important support for the broader application of 2024 aluminum alloy in the aerospace industry and other high-performance fields.
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Frozen shoulder (FS) manifests as progressively worsening pain and a reduction in shoulder range of motion (ROM). Salvianolic acid B (SaB) is recently expected to be used in the treatment of fibrosis diseases including FS. We firstly demonstrate that SaB can effectively hinder the progression of oxidative stress, inflammation, and pathological fibrosis within the synovial tissue in FS, potentially leading to the reduction or reversal of capsule fibrosis and joint stiffness. For further clinical application, we design and synthesize a novel, superior, antioxidant and antibacterial CSMA-PBA/OD-DA (CPDA) hydrogel for the delivery of SaB. In vitro experiments demonstrate that the CPDA hydrogel exhibits excellent biocompatibility and rheological properties, rendering it suitable for intra-articular injections. Upon injection into the contracted joint cavity of FS model rat, the SaB-CPDA hydrogel accelerate the recovery of ROM and exhibit superior anti-fibrosis effect, presenting the promise for the treatment of FS in vivo.
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PURPOSE: The purpose of this study was to investigate a 6-year change in cataract surgical coverage (CSC), effective cataract surgical coverage (eCSC), and visual outcomes in an elderly population in rural southern China. DESIGN: This is a prospective population-based study with a 6-year follow-up. METHODS: The study included rural residents aged 50 years and above in southern China with comprehensive eye examinations at baseline and follow-up in 2014 and 2020, respectively. RESULTS: Five thousand six hundred thirty-eight participants underwent baseline examinations (mean age 66.1±10.2 y, 50.8% women); and 3141 (64.9%) of 4841 eligible survivors attended the 6-year follow-up. Cataract surgical coverage was 41.7% and 40.6% at baseline and follow-up, respectively, while eCSC were 32.6% and 26.6%. In multivariate models, the 6-year likelihood of cataract surgery decreased with older age [odds ratio (OR)=0.97 per year, 95% confidence interval (CI): 0.94, 0.99, P =0.012] and worse baseline presenting uncorrected visual acuity (PVA) in the worse-seeing eye (OR=0.35 per unit logarithm of the minimum angle of resolution (logMAR), 95% CI: 0.25, 0.48, P <0.001), and increased with prior cataract surgical history at baseline (OR=3.88, 95% CI: 1.91, 7.09, P <0.001). The likelihood of receiving effective cataract surgery decreased with worse baseline PVA in the worse eye (OR=0.49 per unit logMAR, 95% CI: 0.24, 0.97, P =0.042) and better-seeing eye (OR=0.68 per unit logMAR, 95% CI: 0.48, 0.95, P =0.026). Posterior capsular opacification was the main reason for PVA <6/18, reporting it in logMAR (0.5) in operated eyes (38.4% at baseline; 28.1% at follow-up). CONCLUSIONS: World Health Organization has established a global target of increasing eCSC by 30% before 2030, but no increase was found in rural southern China between 2014 and 2020, let alone reaching the World Health Organization target of 56.3%. Strategies to improve surgery incidence should focus on older persons and those with worse preoperative PVA.
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Opacificação da Cápsula , Extração de Catarata , Catarata , Idoso , Humanos , Feminino , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Masculino , Estudos Prospectivos , Catarata/complicações , Catarata/epidemiologia , Olho , China/epidemiologiaRESUMO
OBJECTIVE: To investigate the relationships of serum visinin-like protein-1 (VILIP-1), neuron-specific enolase (NSE), and adiponectin (ADP) levels with postoperative cognitive dysfunction (POCD) in elderly patients undergoing general anesthesia and provide a reference for the prevention and treatment of POCD. METHODS: In this retrospective, observational study, 162 elderly patients who underwent general anesthesia were divided into POCD and non-POCD groups according to whether POCD occurred with 24 hours after surgery. Serum VILIP-1, NSE, and ADP levels were measured. RESULTS: Immediately after and 24 hours after surgery, serum VILIP-1 and NSE levels were significantly higher in the POCD group than in the non-POCD group, whereas serum ADP levels were significantly lower in the POCD group. Mini-mental state examination (MMSE) scores significantly differed between the two groups. At 24 hours after surgery, serum VILIP-1 and NSE levels were negatively correlated with MMSE scores in the POCD group, whereas serum ADP levels were positively correlated with MMSE scores in this group. CONCLUSION: Increased serum VILIP-1 and NSE levels and decreased serum ADP levels could be involved in the pathophysiology of POCD in elderly patients after general anesthesia. These serum markers could be used as indicators of POCD in elderly patients undergoing general anesthesia.
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Disfunção Cognitiva , Complicações Cognitivas Pós-Operatórias , Humanos , Idoso , Estudos Retrospectivos , Complicações Pós-Operatórias/diagnóstico , Fosfopiruvato Hidratase , Anestesia Geral/efeitos adversos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/diagnósticoRESUMO
As a major component of the cryosphere, permafrost plays important roles in the climate system and land surface processes of the Earth. Owing to the rapidly warming climate, permafrost over the globe has degraded in recent decades. However, quantifying the distribution and temporal changes in permafrost is challenging. In this study, we modified the widely used surface frost number model by considering the spatial distribution of soil hydrothermal properties and then revisited the spatiotemporal patterns of permafrost distribution and its changes during the past decades (1961-2017) in China. We found that the modified surface frost number model performs well in simulating permafrost extent in China, with the overall accuracy and kappa coefficients being 0.92 and 0.78 in the calibration (1980s) and 0.94 and 0.77 in the validation period (2000s). Based on the modified model, we also found that permafrost extent in China demonstrated a significant decreasing trend over the past decades, especially on the Qinghai-Tibet Plateau (QTP), with a trend of -1.15 × 104 km2/yr (P < 0.01). Moreover, there is a significant relationship between ground surface temperature and permafrost distribution area, with the R2 being 0.41, 0.42, and 0.77 in NE and NW China and on the QTP. The sensitivity of permafrost extent to ground surface temperature in NE China, NW China, and the QTP, respectively, was -8.56 × 104, -1.97 × 104, and -34.60 × 104 km2/°C, respectively. Permafrost degradation has accelerated since the late 1980s, possibly due to increased climate warming. This study is of great significance for improving permafrost distribution simulation at large spatial scales (trans-regional) and for offering vital information for adapting to climate change in cold regions.
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There are major differences in duration and scale at which limb development and regeneration proceed, raising the question to what extent regeneration is a recapitulation of development. We address this by analyzing skeletal elements using a combination of micro-CT imaging, molecular profiling and clonal cell tracing. We find that, in contrast to development, regenerative skeletal growth is accomplished based entirely on cartilage expansion prior to ossification, not limiting the transversal cartilage expansion and resulting in bulkier skeletal parts. The oriented extension of salamander cartilage and bone appear similar to the development of basicranial synchondroses in mammals, as we found no evidence for cartilage stem cell niches or growth plate-like structures during neither development nor regeneration. Both regenerative and developmental ossification in salamanders start from the cortical bone and proceeds inwards, showing the diversity of schemes for the synchrony of cortical and endochondral ossification among vertebrates.
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Osteogênese , Urodelos , Animais , Osso e Ossos , Cartilagem , Divisão Celular , MamíferosRESUMO
Sustainable, resilient urban water management is fundamental to good environmental and public health. As an interdisciplinary task, it faces enormous challenges from project complexity, network dynamics and the tacit nature of knowledge being communicated between actors involved in design, decisions and delivery. Among others, some critical and persistent challenges to the implementation of sustainable urban water management include the lack of knowledge and expertise, lack of effective communication and collaboration, and lack of shared understanding and context. Using the Chinese Sponge City programme as a case study, this paper draws on the perspectives of Polanyi and Collins to investigate the extent to which knowledge can be used and exchanged between actors. Using Collins' conceptualisation of the terrain of tacit knowledge, the study identifies the use of relational, somatic and collective tacit knowledge (CTK) in the Sponge City pilot project. Structured interviews with 38 people working on a Sponge City pilot project provided data that was rigorously analysed using qualitative thematic analysis. The paper is original in identifying different types of tacit knowledge in urban water management, and the potential pathways for information and messages being communicated between actors. The methods and results provide the groundwork for analysing the access and mobilisation of tacit knowledge in the Sponge City pilot project, with relevance for other complex, interdisciplinary environmental projects and programmes.
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Molecule like silver quantum clusters ([Agm]n+ QCs) exhibit an ultrasmall size confinement resulting in efficient broadband fluorescence. However, free [Agm]n+ QCs are also chemically active, so their stabilization is required for practical applications. We report in this work a phosphate oxyfluoride glass network enabled stabilization strategy of [Agm]n+ QCs. A series of silver-doped P2O5-ZnF2-xAg glasses were prepared by a conventional melt-and-quench method. The NMR and XPS results reveal that two types of [P(O,F)4] tetrahedrons (Q1, Q2) form chain structures and Zn(iv) connects [P(O,F)4] chains into a 3-dimension network in the glasses. The frameworks with limited void spaces were designed to restrict the polymerization degree, m, of [Agm]n+ QCs; the negatively charged tetrahedrons were designed to restrict the charge, n, of [Agm]n+ QCs. Through optical and mass spectroscopy studies, silver quantum clusters, [Ag2]2+ and [Ag4]2+, were identified to be charge compensated by [ZnO4] tetrahedrons and surrounded with [P(O,F)4] complex anions. The fluorescence thus gives high quantum efficiencies of 55.2% and 83.4%, for P2O5-ZnF2-xAg glass stabilized [Ag2]2+ and [Ag4]2+ QCs, respectively. This further reveals that the peak fixed fluorescence of [Ag2]2+ and [Ag4]2+ can be described by molecular fluorescence mechanisms. These are parity-allowed singlet-singlet transitions (S1 â S0), parity-forbidden triplet-singlet transitions (T1 â S0) and intersystem crossings between singlets (S1) and triplets (T1). The phonon coupled intersystem crossing between singlets (S1) and triplets (T1) determines the phosphate stabilized [Ag4]2+ QCs to exhibit a series of temperature dependent fluorescence behaviors. These include fluorescence intensity (at 50-200 K), intensity ratio (FIR) (at 50-200 K), peak shift (at 100-300 K) and lifetime (at 300-450 K) with maximum sensitivities of 1.27% K-1, 0.94% K-1, 0.29% K-1 and 0.41% K-1, respectively. Therefore, phosphate stabilized [Ag4]2+ QCs can be applied as temperature sensing probes, especially at low temperatures (10-300 K) and for color-based visualized temperature sensors.
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Lithium (Li) metal anode is a promising candidate for next-generation high capacity energy storage systems. Unfortunately, the uneven deposition/dissolution of Li metal hinders its wide applications. Herein, a robust and deformable polymer electrolyte film as the advanced protective layer on Li metal is developed by a simple tape-casting method, in which the polymer endows a comfortable interfacial contact as well as membrane flexibility to adapt the volume change, while the coordination between the polymer and Li salt provides fast Li+ ion diffusion channels. The modified Li metal anodes deliver a stable cycling over 1000 cycles under a high current density of 3 mA cm-2 in the ether-based electrolyte. The enhanced cycling performance at high current densities are mainly attributed to the Li plating occurred beneath the ion-conducting protective layer, which facilitates Li+ ion uniform distribution and further suppresses Li dendrite growth. Accordingly, constructing a polymer electrolyte protective film onto the Li metal anodes is a facile and low-cost methodology to drive the Li metal anode toward practical application.
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BACKGROUND: Premature ejaculation is a form of male sexual dysfunction. As people's lifestyle changes and the population ages, the incidence of premature ejaculation continues to increase. Many clinical trials have proven that Chinese medicine has a significant effect in the treatment of premature ejaculation. In this systematic review, we aim to evaluate the effectiveness and safety of Traditional Chinese medicine for premature ejaculation. METHODS: We will search for PubMed, Cochrane Library, AMED, EMbase, WorldSciNet; Nature, Science online and China Journal Full-text Database (CNKI), China Biomedical Literature CD-ROM Database (CBM), and related randomized controlled trials included in the China Resources Database. The time is limited from the construction of the library to April 2019. We will use the criteria provided by Cochrane 5.1.0 for quality assessment and risk assessment of the included studies, and use the Revman 5.3 and Stata13.0 software for meta-analysis of the effectiveness, recurrence rate, and symptom scores of premature ejaculation. ETHICS AND DISSEMINATION: This systematic review will evaluate the efficacy and safety of Traditional Chinese medicine for treating premature ejaculation. Because all of the data used in this systematic review and meta-analysis has been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process Trial. TRIAL REGISTRATION NUMBER: PROSPERO CRD42017065316.
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Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Ejaculação Precoce/tratamento farmacológico , China , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Projetos de PesquisaRESUMO
Salamanders exhibit an extraordinary ability among vertebrates to regenerate complex body parts. However, scarce genomic resources have limited our understanding of regeneration in adult salamanders. Here, we present the ~20 Gb genome and transcriptome of the Iberian ribbed newt Pleurodeles waltl, a tractable species suitable for laboratory research. We find that embryonic stem cell-specific miRNAs mir-93b and mir-427/430/302, as well as Harbinger DNA transposons carrying the Myb-like proto-oncogene have expanded dramatically in the Pleurodeles waltl genome and are co-expressed during limb regeneration. Moreover, we find that a family of salamander methyltransferases is expressed specifically in adult appendages. Using CRISPR/Cas9 technology to perturb transcription factors, we demonstrate that, unlike the axolotl, Pax3 is present and necessary for development and that contrary to mammals, muscle regeneration is normal without functional Pax7 gene. Our data provide a foundation for comparative genomic studies that generate models for the uneven distribution of regenerative capacities among vertebrates.
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Extremidades/fisiologia , Genoma/genética , MicroRNAs/genética , Pleurodeles/genética , Regeneração/genética , Ambystoma mexicanum/genética , Animais , Sistemas CRISPR-Cas , Elementos de DNA Transponíveis/genética , Células-Tronco Embrionárias/metabolismo , Edição de Genes , Perfilação da Expressão Gênica , Genômica , Músculo Esquelético/fisiologia , Fator de Transcrição PAX3/genética , Fator de Transcrição PAX7/genética , Proto-Oncogenes/genética , Regeneração/fisiologiaRESUMO
OBJECTIVE: To observe the expression mode and modulation effects of lncRNA-Paupar in the process of bupivacaine induced neurotoxicity. METHODS: Dorsal root ganglion (DRG) neurons were cultured and neurotoxicity model was produced on it. And the expression of lncRNA-Paupar was evaluated by qRT-PCR. Lnc-Paupar specific siRNA-P and random control group siRNA-C were constructed,200 nmol/L siRNA-P,siRNA-C were transfected into ganglion cells and the apoptosis rate of transfected cells were observed by TUNEL method. The JNK and phosphorylated JNK (p-JNK) protein expression were observed with Western blot,respectively. RESULTS: LncRNA-Paupar was significantly up-regulated during the process of bupivacaine induced neurotoxicity and siRNA mediated lncRNA-Paupar down-regulation protected DRG neurons cells from apoptosis. Both JNK and p-JNK protein were reduced in siRNA transfected cells exemplified by Western blot. CONCLUSION: LncRNA-Paupar could induced neurotoxicity through JNK pathway.
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Apoptose , Bupivacaína/toxicidade , Gânglios Espinais/citologia , Neurônios/efeitos dos fármacos , RNA Longo não Codificante/genética , Animais , Células Cultivadas , Regulação para Baixo , TransfecçãoRESUMO
A series of L-shaped ortho-quinone analogs were designed by analyzing the binding mode with NQO1. Metabolic studies demonstrated that compounds 2m, 2n and 2q exhibited higher metabolic rates than ß-lapachone. The docking studies, which supported the rationalization of the metabolic studies, constituted a prospective rational basis for the development of optimized ortho-quinone analogs. Besides, good substrates (2m, 2n and 2r) for NQO1 showed higher selective toxicity than ß-lapachone toward A549 (NQO1-rich) cancer cells versus H596 (NQO1-deficient) cells. Determination of superoxide (O2(â¢-)) production and in vitro cytotoxicity evaluation in the presence of the NQO1 inhibitor dicoumarol confirmed that the ortho-quinones exerted their antitumor activity through NQO1-mediated ROS production by redox cycling. It was suggested that the L-shaped quinone substrates for NQO1 possessed better specificity and safety than ß-lapachone.