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1.
Complement Ther Med ; 82: 103046, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38704101

RESUMO

BACKGROUND: Despite being widely applied in clinical practice, the wake-promoting effect of acupuncture in poststroke coma patients remains controversial. OBJECTIVE: This study aimed to evaluate the efficacy of acupuncture for the treatment of poststroke coma. METHODS: Randomized controlled trials (RCTs) of acupuncture for treating poststroke coma were identified in PubMed, Cochrane Library, EMBASE, CNKI, WanFang and VIP up to 25 November 2023. The main outcomes were Glasgow Coma Scale (GCS) score, National Institute of Health Stroke Scale (NIHSS) score, awakening ratio and clinically effective ratio. Stata 17 and Review Manager 5.4 software were used for mate analysis. RESULTS: A total of 34 RCTs involving 2757 patients were included. GCS (WMD = 1.78; 95% CI: 1.35 to 2.21) and NIHSS score (WMD = -2.84; 95% CI: -3.84 to -1.84) were significantly increased in acupuncture group compared with control group. Acupuncture combined with routine treatment may be better than routine treatment in improving the awakening ratio (RR= 1.65; 95% CI: 1.24 to 2.91) and the clinically effective ratio (RR= 1.20; 95% CI: 1.13 to 1.27). Some methodological flaws were identified in the included studies, including non-implementation of blinding, inappropriate disease assessment and heterogeneous interventions. CONCLUSIONS: The existing evidence suggests that acupuncture combined with conventional treatment may be an effective treatment for poststroke coma patients. In the meantime, more high-quality RCTs are needed to demonstrate these findings due to methodological weaknesses like randomization, blinding, heterogeneous interventions and long-term follow-up.

2.
Sci Rep ; 14(1): 11008, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744845

RESUMO

Multiple studies have shown knockdown of chromobox 7 (CBX7) promotes the regenerative capacity of various cells or tissues. We examined the effect of CBX7 on hepatocyte proliferation and liver regeneration after 2/3 hepatectomy in a mouse model. For in vitro experiments, NCTC 1469 and BNL CL.2 hepatocytes were co-transfected with siRNA-CBX7-1 (si-CBX7-1), siRNA-CBX7-2 (si-CBX7-2), pcDNA-CBX7, si-BMI1-1, si-BMI1-2, pcDNA-BMI1, or their negative control. For in vivo experiments, mice were injected intraperitoneally with lentivirus-packaged shRNA and shRNA CBX7 before hepatectomy. Our results showed that CBX7 was rapidly induced in the early stage of liver regeneration. CBX7 regulated hepatocyte proliferation, cell cycle, and apoptosis of NCTC 1469 and BNL CL.2 hepatocytes. CBX7 interacted with BMI1 and inhibited BMI1 expression in hepatocytes. Silencing BMI1 aggregated the inhibitory effect of CBX7 overexpression on hepatocyte viability and the promotion of apoptosis. Furthermore, silencing BMI1 enhanced the regulatory effect of CBX7 on Nrf2/ARE signaling in HGF-induced hepatocytes. In vivo, CBX7 silencing enhanced liver/body weight ratio in PH mice. CBX7 silencing promoted the Ki67-positive cell count and decreased the Tunel-positive cell count after hepatectomy, and also increased the expression of nuclear Nrf2, HO-1, and NQO-1. Our results suggest that CBX7 silencing may increase survival following hepatectomy by promoting liver regeneration.


Assuntos
Apoptose , Proliferação de Células , Hepatócitos , Regeneração Hepática , Fator 2 Relacionado a NF-E2 , Complexo Repressor Polycomb 1 , Transdução de Sinais , Animais , Complexo Repressor Polycomb 1/metabolismo , Complexo Repressor Polycomb 1/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Camundongos , Hepatócitos/metabolismo , Regeneração Hepática/genética , Apoptose/genética , Hepatectomia , Masculino , Inativação Gênica , Camundongos Endogâmicos C57BL , Fígado/metabolismo
3.
Sci Data ; 11(1): 492, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744849

RESUMO

Surface ozone is an important air pollutant detrimental to human health and vegetation productivity, particularly in China. However, high resolution surface ozone concentration data is still lacking, largely hindering accurate assessment of associated environmental impacts. Here, we collected hourly ground ozone observations (over 6 million records), remote sensing products, meteorological data, and social-economic information, and applied recurrent neural networks to map hourly surface ozone data (HrSOD) at a 0.1° × 0.1° resolution across China during 2015-2020. The coefficient of determination (R2) values in sample-based, site-based, and by-year cross-validations were 0.72, 0.65 and 0.71, respectively, with the root mean square error (RMSE) values being 11.71 ppb (mean = 30.89 ppb), 12.81 ppb (mean = 30.96 ppb) and 11.14 ppb (mean = 31.26 ppb). Moreover, it exhibits high spatiotemporal consistency with ground-level observations at different time scales (diurnal, seasonal, annual), and at various spatial levels (individual sites and regional scales). Meanwhile, the HrSOD provides critical information for fine-resolution assessment of surface ozone impacts on environmental and human benefits.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Ozônio , Ozônio/análise , China , Poluentes Atmosféricos/análise , Estações do Ano , Redes Neurais de Computação , Poluição do Ar/análise , Humanos
4.
Microcirculation ; : e12854, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690631

RESUMO

OBJECTIVE: Designing physiologically adequate microvascular trees is of crucial relevance for bioengineering functional tissues and organs. Yet, currently available methods are poorly suited to replicate the morphological and topological heterogeneity of real microvascular trees because the parameters used to control tree generation are too simplistic to mimic results of the complex angiogenetic and structural adaptation processes in vivo. METHODS: We propose a method to overcome this limitation by integrating a conditional deep convolutional generative adversarial network (cDCGAN) with a local fractal dimension-oriented constrained constructive optimization (LFDO-CCO) strategy. The cDCGAN learns the patterns of real microvascular bifurcations allowing for their artificial replication. The LFDO-CCO strategy connects the generated bifurcations hierarchically to form microvascular trees with a vessel density corresponding to that observed in healthy tissues. RESULTS: The generated artificial microvascular trees are consistent with real microvascular trees regarding characteristics such as fractal dimension, vascular density, and coefficient of variation of diameter, length, and tortuosity. CONCLUSIONS: These results support the adoption of the proposed strategy for the generation of artificial microvascular trees in tissue engineering as well as for computational modeling and simulations of microcirculatory physiology.

5.
Bioconjug Chem ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738511

RESUMO

Radiation therapy is one of the most common treatments for cancer. However, enhancing tumors' radiation sensitivity and overcoming tolerance remain a challenge. Previous studies have shown that the Ras signaling pathway directly influences tumor radiation sensitivity. Herein, we designed a series of Ras-targeting stabilized peptides, with satisfactory binding affinity (KD = 0.13 µM with HRas) and good cellular uptake. Peptide H5 inhibited downstream phosphorylation of ERK and increased radio-sensitivity in HeLa cells, resulting in significantly reduced clonogenic survival. The stabilized peptides, designed with an N-terminal nucleation strategy, acted as potential radio-sensitizers and broadened the applications of this kind of molecule. This is the first report of using stabilized peptides as radio-sensitizers, broadening the applications of this kind of molecule.

6.
Glob Chang Biol ; 30(5): e17303, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38741339

RESUMO

Nitrous oxide (N2O) emissions from livestock manure contribute significantly to the growth of atmospheric N2O, a powerful greenhouse gas and dominant ozone-depleting substance. Here, we estimate global N2O emissions from livestock manure during 1890-2020 using the tier 2 approach of the 2019 Refinement to the 2006 IPCC Guidelines. Global N2O emissions from livestock manure increased by ~350% from 451 [368-556] Gg N year-1 in 1890 to 2042 [1677-2514] Gg N year-1 in 2020. These emissions contributed ~30% to the global anthropogenic N2O emissions in the decade 2010-2019. Cattle contributed the most (60%) to the increase, followed by poultry (19%), pigs (15%), and sheep and goats (6%). Regionally, South Asia, Africa, and Latin America dominated the growth in global emissions since the 1990s. Nationally, the largest emissions were found in India (329 Gg N year-1), followed by China (267 Gg N year-1), the United States (163 Gg N year-1), Brazil (129 Gg N year-1) and Pakistan (102 Gg N year-1) in the 2010s. We found a substantial impact of livestock productivity, specifically animal body weight and milk yield, on the emission trends. Furthermore, a large spread existed among different methodologies in estimates of global N2O emission from livestock manure, with our results 20%-25% lower than those based on the 2006 IPCC Guidelines. This study highlights the need for robust time-variant model parameterization and continuous improvement of emissions factors to enhance the precision of emission inventories. Additionally, urgent mitigation is required, as all available inventories indicate a rapid increase in global N2O emissions from livestock manure in recent decades.


Assuntos
Gado , Esterco , Óxido Nitroso , Óxido Nitroso/análise , Esterco/análise , Animais , Poluentes Atmosféricos/análise
7.
Cell Commun Signal ; 22(1): 227, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38610001

RESUMO

BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors of the head and neck. Vasculogenic mimicry (VM) is crucial for tumor growth and metastasis and refers to the formation of fluid channels by invasive tumor cells rather than endothelial cells. However, the regulatory mechanisms underlying VM during the malignant progression of LSCC remain largely unknown. METHODS: Gene expression and clinical data for LSCC were obtained from the TCGA and Gene GEO (GSE27020) databases. A risk prediction model associated with VM was established using LASSO and Cox regression analyses. Based on their risk scores, patients with LSCC were categorized into high- and low-risk groups. The disparities in immune infiltration, tumor mutational burden (TMB), and functional enrichment between these two groups were examined. The core genes in LSCC were identified using the machine learning (SVM-RFE) and WGCNA algorithms. Subsequently, the involvement of bone morphogenetic protein 2 (BMP2) in VM and metastasis was investigated both in vitro and in vivo. To elucidate the downstream signaling pathways regulated by BMP2, western blotting was performed. Additionally, ChIP experiments were employed to identify the key transcription factors responsible for modulating the expression of BMP2. RESULTS: We established a new precise prognostic model for LSCC related to VM based on three genes: BMP2, EPO, and AGPS. The ROC curves from both TCGA and GSE27020 validation cohorts demonstrated precision survival prediction capabilities, with the nomogram showing some net clinical benefit. Multiple algorithm analyses indicated BMP2 as a potential core gene. Further experiments suggested that BMP2 promotes VM and metastasis in LSCC. The malignant progression of LSCC is promoted by BMP2 via the activation of the PI3K-AKT signaling pathway, with the high expression of BMP2 in LSCC resulting from its transcriptional activation by runt-related transcription factor 1 (RUNX1). CONCLUSION: BMP2 predicts poor prognosis in LSCC, promotes LSCC VM and metastasis through the PI3K-AKT signaling pathway, and is transcriptionally regulated by RUNX1. BMP2 may be a novel, precise, diagnostic, and therapeutic biomarker of LSCC.


Assuntos
Proteína Morfogenética Óssea 2 , Neoplasias de Cabeça e Pescoço , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core , Células Endoteliais , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Transdução de Sinais
8.
ACS Chem Biol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662199

RESUMO

Targeted protein degradation is becoming more and more important in the field of drug development. Compared with proteasomal-based degraders, lysosomal-based degraders have a broader target spectrum of targets, which have been demonstrated to have great potential, especially in degrading undruggable proteins. Recently, we developed a programmable and facile screening PROTAC development platform based on peptide self-assembly termed split-and-mix PROTAC (SM-PROTAC). In this study, we applied this technology for the development of lysosome-based degraders, named a split-and-mix chaperone-mediated autophagy-based degrader (SM-CMAD). We successfully demonstrated SM-CMAD as a universal platform by degrading several targets, including ERα, AR, MEK1/2, and BCR-ABL. Different from other lysosomal-based degraders, SM-CMAD was capable of facile screening with programmable ligand ratios. We believe that our work will promote the development of other multifunctional molecules and clinical translation for lysosomal-based degraders.

9.
Adv Sci (Weinh) ; : e2307754, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605600

RESUMO

Neoantigen peptides hold great potential as vaccine candidates for tumor immunotherapy. However, due to the limitation of antigen cellular uptake and cross-presentation, the progress with neoantigen peptide-based vaccines has obviously lagged in clinical trials. Here, a stapling peptide-based nano-vaccine is developed, comprising a self-assembly nanoparticle driven by the nucleic acid adjuvant-antigen conjugate. This nano-vaccine stimulates a strong tumor-specific T cell response by activating antigen presentation and toll-like receptor signaling pathways. By markedly improving the efficiency of antigen/adjuvant co-delivery to the draining lymph nodes, the nano-vaccine leads to 100% tumor prevention for up to 11 months and without tumor recurrence, heralding the generation of long-term anti-tumor memory. Moreover, the injection of nano-vaccine with signal neoantigen eliminates the established MC-38 tumor (a cell line of murine carcinoma of the colon without exogenous OVA protein expression) in 40% of the mice by inducing potent cytotoxic T lymphocyte infiltration in the tumor microenvironment without substantial systemic toxicity. These findings represent that stapling peptide-based nano-vaccine may serve as a facile, general, and safe strategy to stimulate a strong anti-tumor immune response for the neoantigen peptide-based personalized tumor immunotherapy.

10.
Carbohydr Polym ; 334: 122058, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553243

RESUMO

Global public health is seriously threatened by thrombotic disorders because of their high rates of mortality and disability. Most thrombolytic agents, especially protein-based pharmaceuticals, have a short half-life in circulation, reducing their effectiveness in thrombolysis. The creation of an intelligent drug delivery system that delivers medication precisely and releases it under regulated conditions at nearby thrombus sites is essential for effective thrombolysis. In this article, we present a unique medication delivery system (MCRUA) that selectively targets platelets and releases drugs by stimulation from the thrombus' microenvironment. The thrombolytic enzyme urokinase-type plasminogen-activator (uPA) and the anti-inflammatory medication Aspirin (acetylsalicylic acid, ASA) are both loaded onto pH-sensitive CaCO3/cyclodextrin crosslinking metal-organic frameworks (MC) that make up the MCRUA system. c(RGD) is functionalized on the surface of MC, which is functionalized by RGD to an esterification reaction. Additionally, the thrombus site's acidic microenvironment causes MCRUA to disintegrate to release uPA for thrombolysis and aiding in vessel recanalization. Moreover, cyclodextrin-encapsulated ASA enables the treatment of the inflammatory environment within the thrombus, enhancing the antiplatelet aggregation effects and promoting cooperative thrombolysis therapy. When used for thrombotic disorders, our drug delivery system (MCRUA) promotes thrombolysis, suppresses rethrombosis, and enhances biosafety with fewer hemorrhagic side effects.


Assuntos
Ciclodextrinas , Estruturas Metalorgânicas , Trombose , Humanos , Terapia Trombolítica , Ciclodextrinas/uso terapêutico , Fibrinolíticos/farmacologia , Fibrinolíticos/uso terapêutico , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Trombose/tratamento farmacológico , Aspirina/farmacologia , Oligopeptídeos
11.
Materials (Basel) ; 17(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473471

RESUMO

To investigate the influence of temperature and humidity variations on creep in high-performance concrete beams, beam tests were conducted in both natural and laboratory settings. The findings indicate that the variations in creep primarily stem from temperature changes, whereas humidity changes have little influence on fluctuations in both basic creep and total creep. The influence of humidity on creep is more strongly reflected in the magnitude of creep. Functions describing the influence of temperature and humidity on the creep behavior of high-performance concrete (HPC) subjected to fluctuating conditions are proposed. The findings were employed to examine creep deformation in engineering applications across four places. This study complements the correction method for the creep of members under fluctuating temperature and humidity. This research application can provide a basis for the calculation of the long-term deformation of HPC structures in natural environments.

12.
Meat Sci ; 213: 109481, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38461675

RESUMO

Beef is a popular meat product that can spoil and lose quality during postharvest handling and storage. This review examines different preservation methods for beef, from conventional techniques like low-temperature preservation, irradiation, vacuum packing, and chemical preservatives, to novel approaches like bacteriocin, essential oil, and non-thermal technologies. It also discusses how these methods work and affect beef quality. The review shows that beef spoilage is mainly due to enzymatic and microbial activities that impact beef freshness, texture, and quality. Although traditional preservation methods can extend beef shelf life, they have some drawbacks and limitations. Therefore, innovative preservation methods have been created and tested to improve beef quality and safety. These methods have promising results and potential applications in the beef industry. However, more research is needed to overcome the challenges and barriers for their commercialization. This review gives a comprehensive and critical overview of the current and emerging preservation methods for beef and their implications for the beef supply chain.


Assuntos
Conservação de Alimentos , Carne Vermelha , Animais , Bovinos , Conservação de Alimentos/métodos , Carne Vermelha/microbiologia , Armazenamento de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Microbiologia de Alimentos , Vácuo , Manipulação de Alimentos/métodos
13.
ACS Nano ; 18(10): 7633-7643, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38411092

RESUMO

The potential for optimizing ion transport through triply periodic minimal surface (TPMS) structures renders promising electrochemical applications. In this study, as a proof-of-concept, we extend the inherent efficiency and mathematical beauty of TPMS structures to fabricate liquid-crystalline electrolytes with high ionic conductivity and superior structural stability for aqueous rechargeable zinc-ion batteries. The specific topological configuration of the liquid-crystalline electrolytes, featuring a Gyroid geometry, enables the formation of a continuous ion conduction pathway enriched with confined water. This, in turn, promotes the smooth transport of charge carriers and contributes to high ionic conductivity. Meanwhile, the quasi-solid hydrophobic phase assembled by hydrophobic alkyl chains exhibits notable rigidity and toughness, enabling uniform and compact dendrite-free Zn deposition. These merits synergistically enhance the overall performance of the corresponding full batteries. This work highlights the distinctive role of TPMS structures in developing high-performance, liquid-crystalline electrolytes, which can provide a viable route for the rational design of next-generation quasi-solid-state electrolytes.

14.
BMC Public Health ; 24(1): 538, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383355

RESUMO

BACKGROUND: Large-scale outbreaks of scrub typhus combined with its emergence in new areas as a vector-borne rickettsiosis highlight the ongoing neglect of this disease. This study aims to explore the long-term changes and regional leading factors of scrub typhus in China, with the goal of providing valuable insights for disease prevention and control. METHODS: This study utilized a Bayesian space-time hierarchical model (BSTHM) to examine the spatiotemporal heterogeneity of scrub typhus and analyze the relationship between environmental factors and scrub typhus in southern and northern China from 2006 to 2018. Additionally, a GeoDetector model was employed to assess the predominant influences of geographical and socioeconomic factors in both regions. RESULTS: Scrub typhus exhibits a seasonal pattern, typically occurring during the summer and autumn months (June to November), with a peak in October. Geographically, the high-risk regions, or hot spots, are concentrated in the south, while the low-risk regions, or cold spots, are located in the north. Moreover, the distribution of scrub typhus is influenced by environment and socio-economic factors. In the north and south, the dominant factors are the monthly normalized vegetation index (NDVI) and temperature. An increase in NDVI per interquartile range (IQR) leads to a 7.580% decrease in scrub typhus risk in northern China, and a 19.180% increase in the southern. Similarly, of 1 IQR increase in temperature reduces the risk of scrub typhus by 10.720% in the north but increases it by 15.800% in the south. In terms of geographical and socio-economic factors, illiteracy rate and altitude are the key determinants in the respective areas, with q-values of 0.844 and 0.882. CONCLUSIONS: These results indicated that appropriate climate, environment, and social conditions would increase the risk of scrub typhus. This study provided helpful suggestions and a basis for reasonably allocating resources and controlling the occurrence of scrub typhus.


Assuntos
Tifo por Ácaros , Humanos , Tifo por Ácaros/epidemiologia , Teorema de Bayes , China/epidemiologia , Estações do Ano , Fatores Econômicos , Incidência
15.
iScience ; 27(3): 109195, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38420584

RESUMO

The interactions between human and natural systems and their effects have unforeseen results, particularly in the management of water resources. Using water stress mitigation as an example, a water resources management effect index (WRMEI) was created to quantitatively evaluate the trends of water management effects. This revealed that the WRMEI was decreasing due to the impact of the water resources management process. The findings demonstrate that water resources management has unintended effects: there was a gap between the expectation of water stress to be mitigated and the actual results of water stress increasing. That is caused by human activities in water utilization: (1) increasing available water resources from water transfer was not utilized sparingly in the receiving cities-increased water transfers from external sources increase domestic water consumption per capita; (2) improving water efficiency has a positive effect on mitigating water stress, but the population growth decreased the efficiency. It was concluded that much greater attention needs to be paid to water conservation in residential and living use to counter these unintended water management effects.

16.
Mol Plant ; 17(3): 438-459, 2024 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-38310351

RESUMO

The spike architecture of wheat plays a crucial role in determining grain number, making it a key trait for optimization in wheat breeding programs. In this study, we used a multi-omic approach to analyze the transcriptome and epigenome profiles of the young spike at eight developmental stages, revealing coordinated changes in chromatin accessibility and H3K27me3 abundance during the flowering transition. We constructed a core transcriptional regulatory network (TRN) that drives wheat spike formation and experimentally validated a multi-layer regulatory module involving TaSPL15, TaAGLG1, and TaFUL2. By integrating the TRN with genome-wide association studies, we identified 227 transcription factors, including 42 with known functions and 185 with unknown functions. Further investigation of 61 novel transcription factors using multiple homozygous mutant lines revealed 36 transcription factors that regulate spike architecture or flowering time, such as TaMYC2-A1, TaMYB30-A1, and TaWRKY37-A1. Of particular interest, TaMYB30-A1, downstream of and repressed by WFZP, was found to regulate fertile spikelet number. Notably, the excellent haplotype of TaMYB30-A1, which contains a C allele at the WFZP binding site, was enriched during wheat breeding improvement in China, leading to improved agronomic traits. Finally, we constructed a free and open access Wheat Spike Multi-Omic Database (http://39.98.48.156:8800/#/). Our study identifies novel and high-confidence regulators and offers an effective strategy for dissecting the genetic basis of wheat spike development, with practical value for wheat breeding.


Assuntos
Estudo de Associação Genômica Ampla , Triticum , Triticum/genética , Melhoramento Vegetal , Redes Reguladoras de Genes/genética , Multiômica , Fatores de Transcrição/genética
17.
J Org Chem ; 89(4): 2807-2811, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38324536

RESUMO

A new asymmetric synthesis of the A/E-ring fragment of C18-diterpenoid alkaloids is described. The crucial contiguous stereogenic centers at C4, C5, and C11 were established through an asymmetric Michael addition/allylation sequence. The unique azabicyclo[3.3.1]nonane motif (A/E rings) was assembled by employing ring-closing metathesis and Mitsunobu reaction as key strategies.

19.
Small ; : e2311578, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363013

RESUMO

Charging LiCoO2 to high voltages yields alluring specific capacities, yet the deleterious phase-transitions lead to significant capacity degradation. Herein, this study demonstrates a novel strategy to stabilize LiCoO2 at 4.6 V by doping with Er and Mg at the Li-site and Co-site, respectively, which is different from the traditional method of doping foreign elements solely at the Co-site. Theoretical calculations and experiments jointly reveal that the inclusion of Mg2+ -dopants at the Co-site curbs the hexagonal-monoclinic phase transitions ≈4.2 V. However, this unintentionally compromises the stability of lattice oxygen in LiCoO2 , exacerbating the undesired phase transition (O3 to H1-3) above 4.45 V. Fascinatingly, the introduction of Er3+ -dopants into Li-sites enhances the stability of lattice oxygen in LiCoO2 , effectively mitigating phase transitions above 4.45 V. Therefore, the Er, Mg co-doped LiCoO2 exhibits high stability over 500 cycles when tested in a half-cell with a cut-off voltage of 4.6 V. Furthermore, the Er, Mg-doped LiCoO2 //graphite pouch-type full cell demonstrates a high energy density of 310.8 Wh kg-1 , preserving 91.3% of its energy over 100 cycles.

20.
PLoS One ; 19(2): e0295263, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38354116

RESUMO

Most semantic segmentation works have obtained accurate segmentation results through exploring the contextual dependencies. However, there are several major limitations that need further investigation. For example, most approaches rarely distinguish different types of contextual dependencies, which may pollute the scene understanding. Moreover, local convolutions are commonly used in deep learning models to learn attention and capture local patterns in the data. These convolutions operate on a small neighborhood of the input, focusing on nearby information and disregarding global structural patterns. To address these concerns, we propose a Global Domain Adaptation Attention with Data-Dependent Regulator (GDAAR) method to explore the contextual dependencies. Specifically, to effectively capture both the global distribution information and local appearance details, we suggest using a stacked relation approach. This involves incorporating the feature node itself and its pairwise affinities with all other feature nodes within the network, arranged in raster scan order. By doing so, we can learn a global domain adaptation attention mechanism. Meanwhile, to improve the features similarity belonging to the same segment region while keeping the discriminative power of features belonging to different segments, we design a data-dependent regulator to adjust the global domain adaptation attention on the feature map during inference. Extensive ablation studies demonstrate that our GDAAR better captures the global distribution information for the contextual dependencies and achieves the state-of-the-art performance on several popular benchmarks.


Assuntos
Benchmarking , Equipamentos Médicos Duráveis , Semântica , Processamento de Imagem Assistida por Computador
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