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1.
Small ; 20(27): e2310915, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38267813

RESUMO

Lithium dendrites are easily generated for excessively-solved lithium ions (Li+) inside the lithium metal batteries, which will lead serious safety issues. In this experiment, carbon spheres (CS) are successfully anchored on TiO2 (CS@TiO2) in the hydrothermal polymerization, which is filtrated on the commercial PE separator (CS@TiO2@PE). The negative charge in CS can suppress random diffusion of anions through electrostatic interactions. Density functional theory (DFT) calculations show that CS contributes to the desolvation of Li+, thereby increasing the migration rate of Li+. Furthermore, TiO2 exhibits high affinity to liquid electrolytes and acts as a physical barrier to lithium dendrite formation. CS@TiO2 is a combination of the advantages of CS and TiO2. As results, the Li+ transference number of the CS@TiO2@PE separator can be promoted to 0.63. The Li||Li cell with the CS@TiO2@PE separator exhibits a stable cycle performance for more than 600 h and lower polarization voltage (17 mV) at 1 mA cm-2. The coulombic efficiency (CE) of the Li||Cu cells employe the CS@TiO2@PE separator is 81.63% over 130 cycles. The discharge capacity of LiFePO4||Li cells based on the CS@TiO2@PE separator is 1.73 mAh (capacity retention = 91.53% after 260 cycles). Thus, the CS@TiO2 layer inhibits lithium dendrite formation.

2.
Acta Biochim Biophys Sin (Shanghai) ; 56(6): 892-904, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38733164

RESUMO

Diabetes accelerates vascular senescence, which is the basis for atherosclerosis and stiffness. The activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and oxidative stress are closely associated with progressive senescence in vascular smooth muscle cells (VSMCs). The vascular protective effect of FGF21 has gradually gained increasing attention, but its role in diabetes-induced vascular senescence needs further investigation. In this study, diabetic mice and primary VSMCs are transfected with an FGF21 activation plasmid and treated with a peroxisome proliferator-activated receptor γ (PPARγ) agonist (rosiglitazone), an NLRP3 inhibitor (MCC950), and a spleen tyrosine kinase (SYK)-specific inhibitor, R406, to detect senescence-associated markers. We find that FGF21 overexpression significantly restores the level of catalase (CAT), vascular relaxation, inhibits the intensity of ROSgreen fluorescence and p21 immunofluorescence, and reduces the area of SA-ß-gal staining and collagen deposition in the aortas of diabetic mice. FGF21 overexpression restores CAT, inhibits the expression of p21, and limits the area of SA-ß-gal staining in VSMCs under high glucose conditions. Mechanistically, FGF21 inhibits SYK phosphorylation, the production of the NLRP3 dimer, the expression of NLRP3, and the colocalization of NLRP3 with PYCARD (ASC), as well as NLRP3 with caspase-1, to reverse the cleavage of PPARγ, preserve CAT levels, suppress ROSgreen density, and reduce the expression of p21 in VSMCs under high glucose conditions. Our results suggest that FGF21 alleviates vascular senescence by regulating the SYK-NLRP3 inflammasome-PPARγ-catalase pathway in diabetic mice.


Assuntos
Senescência Celular , Diabetes Mellitus Experimental , Fatores de Crescimento de Fibroblastos , Inflamassomos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular , Proteína 3 que Contém Domínio de Pirina da Família NLR , PPAR gama , Transdução de Sinais , Quinase Syk , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Quinase Syk/metabolismo , Quinase Syk/genética , PPAR gama/metabolismo , PPAR gama/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Inflamassomos/metabolismo , Camundongos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Masculino , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia
3.
Chem Biodivers ; 21(6): e202400507, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38606561

RESUMO

Three new C10 and C12 aliphatic δ-lactones (1-3), three new fatty acid methyl esters (4-6), and eight known compounds (7-14) were isolated from the marine Aureobasidium sp. LUO5. Their structures were established by detailed analyses of the NMR, HRESIMS, optical rotation, and ECD data. All isolates were tested for their inhibitory effects on nitric oxide production in LPS-induced BV-2 cells. Notably, compound 4 displayed the strongest inhibitory effect with the IC50 value of 120.3 nM.


Assuntos
Aureobasidium , Óxido Nítrico , Animais , Camundongos , Aureobasidium/química , Aureobasidium/metabolismo , Linhagem Celular , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Conformação Molecular , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Lactonas
4.
Nanotechnology ; 32(46)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34359059

RESUMO

The strain has been employed for controlled modification of electronical and mechanical properties of two-dimensional (2D) materials. However, the thermal strain-engineered behaviors of the CVD-grown MoS2have not been systematically explored. Here, we investigated the strain-induced structure and properties of CVD-grown triangular MoS2flakes by several advanced atomic force microscopy. Two different kinds of flakes with sharp-corner or vein-like nanostructures are experimentally discovered due to the size-dependent strain behaviors. The critical size of these two kinds of flakes can be roughly estimated at âˆ¼17µm. Within the small flakes, the sharp-corner regions show specific strain-modified properties due to the suffering of large tensile strain. While in the large MoS2flakes, the complicated vein-like nanoripple structures were formed due to the interface slipping process under the larger tensile strain. Our work not only demonstrates the size-specific strain behaviors of MoS2flakes but also sheds light on the artificial design and preparation of strain-engineered nanostructures for the devices based on the 2D materials.

5.
Inorg Chem ; 59(23): 17356-17363, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33210904

RESUMO

Scalable production and controlled doping of large-area two-dimensional transition-metal dichalcogenide films are fundamental steps toward their applications in electronic devices. Although a variety of methods for preparation of wafer-scale transition-metal dichalcogenide films have been developed, it is still challenging to realize homogeneous doping of the large-area films to modulate their electronic properties. In this paper, we report a new chemical vapor deposition (CVD) method for preparation of wafer-scale pristine and doped monolayer MoS2 films on 2-inch sapphire wafers. The molybdenum precursors are supplied in a "face-to-face" manner from a silica gel plate to the sapphire wafer, which guarantees uniform nucleation and growth of monolayer MoS2. This method can be used to prepare substitutionally doped monolayer MoS2 films. By using ReCl3 as the dopant precursor, we have obtained continuous Re-doped monolayer MoS2 films on sapphire wafers. Elemental analysis confirms successful Re-doping of the MoS2 film. Spherical aberration-corrected scanning transmission electron microscopy characterization reveals that the Re atoms are incorporated at the substitutional Mo sites in the MoS2 lattice. The incorporation of Re atoms leads to n-type doping of MoS2 as evidenced by Kelvin probe force microscope studies. Electrical measurements reveal that the transport properties of the Re-doped monolayer MoS2 is dramatically enhanced as compared with the pristine MoS2. The CVD method developed in this study can be applied to the production of a variety of two-dimensional transition-metal dichalcogenide films suitable for applications in electronic devices.

6.
Environ Monit Assess ; 192(9): 585, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32809133

RESUMO

Wetlands are carbon pools for terrestrial ecosystems and play an important role in the global carbon cycle. The Nanhui tidal flat is located at the Yangtze River estuary and has been disturbed by various human activities. However, the effect of human activities on the carbon accumulation capability and carbon storage of wetlands in the Nanhui tidal flat is poorly understood. In this study, the annual carbon accumulation capability and carbon storage of three types of Spartina alterniflora Loisel. wetlands in the Nanhui tidal flat, which were defined as a natural wetland, silt-promoting wetland, and artificial restored wetland, were evaluated by analyzing the plant carbon fixation capability, soil carbon emissions, and soil organic carbon (SOC) density. The results showed that the three wetlands all had a carbon sink effect and the natural wetland, artificial restored wetland, and silt-promoting wetland annually accumulated 7.94, 7.14, and 6.33 kg m-2 CO2, respectively. The existing SOC density in the subsurface soil (0-40 cm) in the natural wetland, silt-promoting wetland, and artificial restored wetland was 23.26, 17.95, and 12.21 kg m-2 CO2, respectively. The natural wetland, with no human disturbance, had a longer duration of waterlogging and greater tidal nutrition inputs than the other wetlands, resulting in a higher plant biomass and lower soil respiration (SR). It therefore had the strongest carbon accumulation capability and highest SOC storage.


Assuntos
Estuários , Áreas Alagadas , Carbono/análise , China , Ecossistema , Monitoramento Ambiental , Rios , Solo
7.
Sci Rep ; 14(1): 7393, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548831

RESUMO

Investigating the impact of train-induced vibration loads on soil hydraulic properties, this study conducted experiments using a self-designed indoor soil seepage platform that incorporates vibration loads. The experiments were complemented with scanning electron microscopy to analyze the influence of train-induced vibration loads on soil hydraulic conductivity and its evolutionary characteristics under different vibration frequencies. The experimental results indicated that as the vibration frequency increases from no vibration (0 Hz) to 20 Hz, the time required for the soil volumetric moisture content to reach its peak and stabilize decreases rapidly. However, after the vibration frequency exceeds 20 Hz, the rate at which the time required for the volumetric moisture content to reach its peak and stabilize decreases slows down. Furthermore, the soil pore water pressure increases with the increase in vibration frequency. At a vibration frequency of 80 Hz, the peak value of pore water pressure increases by 105% compared to the non-vibration state, suggesting that higher vibration frequencies promote the development and acceleration of soil pore moisture migration. Additionally, as the vibration frequency increases, the soil hydraulic conductivity initially experiences a rapid increase, with a growth rate ranging from 40.1 to 47.4%. However, after the frequency exceeds 20 Hz, this growth rate significantly decreases, settling to only 18.6% to 7.8%. When the soil was subjected to a vibration load, the scanning electron microscopy test revealed alterations in its pore structure. Micropores and small pores transformed into macropores and mesopores. Additionally, the microstructural parameters indicated that vibration load decreased the complexity of soil pores, thereby speeding up the hydraulic conduction process. This, in turn, affected the hydraulic properties of the soil and established a relationship between pore structure complexity and soil hydraulic properties.

8.
Eur J Prev Cardiol ; 31(5): 507-518, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37651722

RESUMO

AIMS: Isolated sinus node dysfunction (ISND) is a sinus node dysfunction without atrial fibrillation. A high risk of ischaemic stroke (IS) has been reported in ISND populations. However, current guidelines do not recommend anticoagulation in ISND management. P-wave indicates ISND-related atrial remodelling. P-wave indices and the CHA2DS2-VASc score may contribute to risk stratification for ISND-related IS. METHODS AND RESULTS: In this multi-centre longitudinal cohort, ISND patients were divided into development (n = 1185) and external validation (n = 988) cohorts. Ischaemic stroke prediction capacity of the P-combined score was assessed with regard to discrimination, calibration, and clinical effectiveness. The cut-off value of the score was confirmed by using a restricted cubic spline curve. One hundred and twenty-four (10.46%) ISND patients developed IS [1.63%/year; 95% confidence interval (CI): 1.49-1.78%/year] after a median 3.02-year follow-up in the development cohort. The P-wave terminal force in electrocardiogram-lead V1 (PTFV1) was the only significantly abnormal P-wave index (adjusted hazard ratio: 2.56; 95% CI: 1.72-3.80). Therefore, we incorporated the PTFV1 with the CHA2DS2-VASc score to generate a P-combined score. For a 5-year IS risk, the P-combined score improved Harrell's C-statistic (95% CI) from 0.678 (0.618-0.738) to 0.716 (0.657-0.774) and 0.747 (0.677-0.816) to 0.808 (0.747-0.868) in the development and validation cohorts, respectively, along with calibration and decision curve analyses. The cut-off value of the score was 3 in the development cohort and well-discriminated in the validation cohort. CONCLUSION: Chinese ISND patients have a higher IS risk than the general population. Compared with the CHA2DS2-VASc score, the PTFV1-combined CHA2DS2-VASc score shows a better risk-stratification capacity for ISND-related IS.


By screening the risk factors of ischaemic stroke for isolated sinus node dysfunction (sinus node dysfunction without atrial fibrillation), we developed and validated a new scoring system­P-combined score, which is a combination of an abnormal P-wave terminal force in electrocardiogram-lead V1 (PTFV1) and the CHA2DS2-VASc score. We constructed the P-combined score in the following way: abnormal PTFV1 (2 points), age (1 point for 65­74 years and 2 points for ≥75 years), sex (1 point for female), congestive heart failure (1 point), hypertension (1 point), diabetes mellitus (1 point), vascular disease (1 point), and thrombotic event (2 points). Based on our analysis, we found that the P-combined score showed a strong performance (with a C-statistic of 0.716 for 5 years), which was better than the CHA2DS2-VASc score (C-statistic of 0.678 for 5 years). We also found that the performance of the P-combined score was rigorous in an independent cohort from two external centres (with a C-statistic of 0.808 for 5 years) and outperformed the CHA2DS2-VASc score (C-statistic of 0.747 for 5 years).


Assuntos
Fibrilação Atrial , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/etiologia , Síndrome do Nó Sinusal , Fatores de Risco , Medição de Risco
9.
Endocrine ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914747

RESUMO

PURPOSE: Adrenal venous sampling (AVS) is recommended for subtyping primary aldosteronism (PA). However, in cases of PA, concurrent subclinical Cushing's syndrome (SCS) has the potential to confound AVS results. Pentixafor, a CXC chemokine receptor type 4-specific ligand, has been reported as a promising marker to evaluate functional nature of adrenal adenomas. This study aims to investigate the clinical value of Gallium-68 Pentixafor Positron Emission Tomography-Computed Tomography (68Ga-Pentixafor PET/CT) in the localization diagnosis of patients with PA plus SCS. METHODS: Two patients with a confirmed diagnosis of PA plus SCS underwent AVS and 68Ga-Pentixafor PET/CT. RESULTS: AVS results revealed no lateralization for both patients while 68Ga-Pentixafor PET/CT showed a unilateral adrenal nodule with increased uptake of 68Ga-Pentixafor. Unilateral adrenalectomy was performed based on the results of 68Ga-Pentixafor PET/CT. Subsequently, complete biochemical remission of autonomous aldosterone and cortisol secretion were achieved in both cases. CONCLUSIONS: 68Ga-Pentixafor PET/CT shows promising potential for the localization of aldosterone and cortisol co-secreting adrenal adenoma in patients with PA plus SCS.

10.
iScience ; 27(2): 108974, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38327790

RESUMO

In 2016, the Yangtze River Protection Strategy was proposed and a series of measures were applied to restore the health and function of the Yangtze River ecosystem. However, the impact of these measures on the carbon (C) sink capacity of the Yangtze River estuary wetlands has not been exhaustively studied. In this work, the effects of these measures on the C sink capacity of Yangtze River estuary wetlands were examined through the long-term monitoring of C fluxes, soil respiration, plant growth and water quality. The C flux of the Yangtze River estuary wetlands has become increasingly negative after the implementation of these measures, mainly owing to reduction in soil CO2 emission. The decrease in the chemical fertilizer release and returning farmland to wetland had led to the improvement of water quality in the estuary area, which further reduced soil heterotrophic microbial activity, and ultimately decreasing soil CO2 emissions of estuary wetlands.

11.
Sci Rep ; 14(1): 5383, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443410

RESUMO

Breast density, or the amount of fibroglandular tissue (FGT) relative to the overall breast volume, increases the risk of developing breast cancer. Although previous studies have utilized deep learning to assess breast density, the limited public availability of data and quantitative tools hinders the development of better assessment tools. Our objective was to (1) create and share a large dataset of pixel-wise annotations according to well-defined criteria, and (2) develop, evaluate, and share an automated segmentation method for breast, FGT, and blood vessels using convolutional neural networks. We used the Duke Breast Cancer MRI dataset to randomly select 100 MRI studies and manually annotated the breast, FGT, and blood vessels for each study. Model performance was evaluated using the Dice similarity coefficient (DSC). The model achieved DSC values of 0.92 for breast, 0.86 for FGT, and 0.65 for blood vessels on the test set. The correlation between our model's predicted breast density and the manually generated masks was 0.95. The correlation between the predicted breast density and qualitative radiologist assessment was 0.75. Our automated models can accurately segment breast, FGT, and blood vessels using pre-contrast breast MRI data. The data and the models were made publicly available.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Humanos , Feminino , Imageamento por Ressonância Magnética , Radiografia , Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem
12.
Front Public Health ; 11: 1072944, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844848

RESUMO

Background: With industrialization, urbanization, and modernization, mass sports have entered people's daily lives to maintain their health status. However, less attention has been paid to the heterogeneity and inequality of access to mass sports, especially in developing countries. This study aims to analyze the factors that affect mass sports participation in developing countries represented by China, and explain the changing trends and inequality in the class differentiation and mobility of public sports participation. Methods: The study selected the Chinese General Social Survey (CGSS) data in 2010 and 2018 as the research samples, and used an ordered Probit model and sub-sample regression to analyze the factors and trends of Chinese residents' mass sports participation and the influencing factors. By stratified three-stage probability sampling, the study obtained 4,940 valid responses, including 1,014 in CGSS 2010 and 3926 in CGSS 2018. Results: First, in terms of social factors, urban residents have a higher frequency of sports participation than rural residents. Second, regarding family factors, residents with higher social classes are more likely to participate in sports than those with lower social classes. Third, in terms of self-induced factors, the elderly are more motivated to exercise than the young. Residents with public-sector jobs, high incomes, and higher education levels are keener to participate in sports. Fourth, residents' mass sports participation rate has generally shown an upward trend over time. Fifth, with time changes, the sports participation rate varies between urban and rural areas, between ethnic minorities and Han ethnic, between old and young age groups, and between higher and lower education levels will continue to shrink, but differences between social classes will further increase over time. Conclusions: Our analysis demonstrated that hidden inequality existed in accessing mass sports participation in developing countries, and the self-induced characteristics were significantly correlated with the quality of sports participation. Future public sports policies should address the inequity to ensure equal access to affordable qualified personal mass sports.


Assuntos
Disparidades Socioeconômicas em Saúde , Esportes , Humanos , População do Leste Asiático , Classe Social
13.
Med Image Anal ; 87: 102836, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37201220

RESUMO

Automated tumor detection in Digital Breast Tomosynthesis (DBT) is a difficult task due to natural tumor rarity, breast tissue variability, and high resolution. Given the scarcity of abnormal images and the abundance of normal images for this problem, an anomaly detection/localization approach could be well-suited. However, most anomaly localization research in machine learning focuses on non-medical datasets, and we find that these methods fall short when adapted to medical imaging datasets. The problem is alleviated when we solve the task from the image completion perspective, in which the presence of anomalies can be indicated by a discrepancy between the original appearance and its auto-completion conditioned on the surroundings. However, there are often many valid normal completions given the same surroundings, especially in the DBT dataset, making this evaluation criterion less precise. To address such an issue, we consider pluralistic image completion by exploring the distribution of possible completions instead of generating fixed predictions. This is achieved through our novel application of spatial dropout on the completion network during inference time only, which requires no additional training cost and is effective at generating diverse completions. We further propose minimum completion distance (MCD), a new metric for detecting anomalies, thanks to these stochastic completions. We provide theoretical as well as empirical support for the superiority over existing methods of using the proposed method for anomaly localization. On the DBT dataset, our model outperforms other state-of-the-art methods by at least 10% AUROC for pixel-level detection.


Assuntos
Neoplasias da Mama , Mamografia , Humanos , Feminino , Mamografia/métodos , Aprendizado de Máquina , Neoplasias da Mama/diagnóstico por imagem
14.
Eur J Clin Nutr ; 77(3): 299-307, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36100703

RESUMO

BACKGROUND/OBJECTIVES: The evidence of relationship between dietary intake of folate, vitamin B6 and vitamin B12 and cardiovascular diseases (CVD) in UK populations is limited. We aimed to analyze the association of dietary intake of folate, vitamin B6, and vitamin B12 with CVD events [stroke, myocardial infarction (MI)] and CVD mortality. METHODS: We included 115,664 participants, aged 40-70 years, with no CVD events or cancer at baseline, enrolled between 2006 and 2010 and followed up to the end of 2018. Dietary intake was measured with an online 24-h dietary assessment. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the associations. RESULTS: After multivariate adjustment, higher dietary folate intake was inversely associated with CVDs with hazard ratios of 0.99, 0.92, and 0.88 in groups 2-4 compared with group 1 (the lowest group); inversely associated with stroke with hazard ratios of 0.94, 0.90, and 0.86 groups 2-4 compared to group 1 (lowest group); inversely associated with MI with hazard ratios of 1.01, 0.90 and 0.86 groups 2-4 compared to group 1 (lowest group); inversely associated with CVD mortality with hazard ratios of 0.95, 0.80 and 0.74 Groups 2-4 compared to group 1 (lowest group). Each tablespoon/day higher intake of raw vegetable intake, pieces/day higher intake of fresh fruit intake bowls/week higher intake of cereal intake, and g/day higher intake of dietary fiber were associated with higher intakes of folate every 0.02,0.06,0.05, and 0.08 SD, respectively. E-value analysis suggested robustness to unmeasured confounding. CONCLUSIONS: Each increase in folate intakes was related to 5% lower risks of total CVD events and 10% lower risks of CVD mortality. Our findings support that strengthening dietary folate intake as a primary prevention strategy for CVD events and CVD mortality.


Assuntos
Doenças Cardiovasculares , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Ácido Fólico , Vitamina B 6 , Estudos Prospectivos , Doenças Cardiovasculares/epidemiologia , Vitamina B 12 , Acidente Vascular Cerebral/epidemiologia , Infarto do Miocárdio/epidemiologia , Reino Unido/epidemiologia , Fatores de Risco
15.
Materials (Basel) ; 16(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37297267

RESUMO

In the construction process of an asphalt concrete impermeable core wall, the interlayer bonding of the core wall is the weak link of the core wall structure and also the focus of construction, so it is important to carry out research on the influence of interlayer bonding temperature on the bending performance of an asphalt concrete core wall. In this paper, we study whether asphalt concrete core walls could be treated with cold-bonding by fabricating small beam bending specimens with different interlayer bond temperatures and conducting bending tests on them at 2 °C. The effect of temperature variation on the bending performance of the bond surface under the asphalt concrete core wall is studied through experimental data analysis. The test results show that the maximum value of porosity of bituminous concrete specimens is 2.10% at lower bond surface temperature of -25 °C, which does not meet the specification requirement of less than 2%. The bending stress, strain, and deflection of bituminous concrete core wall increase with the increase of bond surface temperature, especially when the bond surface temperature is less than -10 °C. If the lower bonding surface temperature is less than 10 °C, the upper layer of asphalt mixture with large grain size aggregate cannot be effectively buried in the low bond surface, resulting in flat fracture and brittle damage to the specimen, which is detrimental to construction quality; therefore, the bonding surface should be heated so that the temperature of the bottom bonding surface is 30 °C. If the lower bonding surface temperature is 10 °C or above, no heating is required.

16.
BMJ Open ; 13(11): e076499, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37977871

RESUMO

OBJECTIVES: The role of cardiac arrhythmia in ischaemic stroke is widely studied, but the size of the stroke risk in patients with sinus node dysfunction (SND) with and without atrial fibrillation (AF) is unclear. This systematic review and meta-analysis aimed to compare the risk of stroke and its associated factors in patients with SND with and without AF. DESIGN: A systematic review and meta-analysis was conducted based on the Grading of Recommendations, Assessment, Development and Evaluation approach. DATA SOURCES: PubMed, EMBASE and Cochrane Database were searched until December 2022. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies that investigate stroke in patients with SND diagnosed with or without AF/atrial flutter. DATA EXTRACTION AND SYNTHESIS: Two independent authors screened studies for inclusion and extracted data. Literature quality assessment was performed using the Newcastle-Ottawa Scale and the Cochrane Collaboration Tool. The overall risk of stroke was estimated using the random-effects model. The generic inverse variance method was used to calculate the pooled estimates of stroke-associated factors. We performed a sensitivity analysis using a fixed-effects model. RESULTS: Of the 929 records retrieved, 6 papers (106 163 patients) met the inclusion criteria. The average yearly stroke incidence in patients with SND was 1.542% (95% CI: 1.334% to 1.749%). The stroke incidence was similar between the isolated SND (1.587%; 95% CI: 1.510% to 1.664%) and non-isolated (SND+AF) (1.660%; 95% CI: 0.705% to 2.615%) groups. AF (HR, 95% CI: 1.53 (1.01 to 2.33)), stroke/transient ischaemia attack/other thrombotic events (HR, 95% CI: 2.54 (1.14 to 5.69)), hypertension (HR, 95% CI: 1.51 (1.11 to 2.07)) and heart failure (HR, 95% CI: 1.41 (1.01 to 1.97)) were associated with stroke in the SND population. CONCLUSION: Our findings suggest that patients with SND carry a similar risk of stroke to those with combined SND and AF. Future studies are needed to investigate whether interventions targeting stroke prevention, such as anticoagulation therapy, can help to prevent stroke in patients with SND. PROSPERO REGISTRATION NUMBER: CRD42023408436.


Assuntos
Fibrilação Atrial , Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Síndrome do Nó Sinusal/diagnóstico , Síndrome do Nó Sinusal/epidemiologia , Síndrome do Nó Sinusal/terapia , Isquemia Encefálica/complicações , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/complicações , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/diagnóstico
17.
Med Image Anal ; 89: 102918, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37595404

RESUMO

Training segmentation models for medical images continues to be challenging due to the limited availability of data annotations. Segment Anything Model (SAM) is a foundation model trained on over 1 billion annotations, predominantly for natural images, that is intended to segment user-defined objects of interest in an interactive manner. While the model performance on natural images is impressive, medical image domains pose their own set of challenges. Here, we perform an extensive evaluation of SAM's ability to segment medical images on a collection of 19 medical imaging datasets from various modalities and anatomies. In our experiments, we generated point and box prompts for SAM using a standard method that simulates interactive segmentation. We report the following findings: (1) SAM's performance based on single prompts highly varies depending on the dataset and the task, from IoU=0.1135 for spine MRI to IoU=0.8650 for hip X-ray. (2) Segmentation performance appears to be better for well-circumscribed objects with prompts with less ambiguity such as the segmentation of organs in computed tomography and poorer in various other scenarios such as the segmentation of brain tumors. (3) SAM performs notably better with box prompts than with point prompts. (4) SAM outperforms similar methods RITM, SimpleClick, and FocalClick in almost all single-point prompt settings. (5) When multiple-point prompts are provided iteratively, SAM's performance generally improves only slightly while other methods' performance improves to the level that surpasses SAM's point-based performance. We also provide several illustrations for SAM's performance on all tested datasets, iterative segmentation, and SAM's behavior given prompt ambiguity. We conclude that SAM shows impressive zero-shot segmentation performance for certain medical imaging datasets, but moderate to poor performance for others. SAM has the potential to make a significant impact in automated medical image segmentation in medical imaging, but appropriate care needs to be applied when using it. Code for evaluation SAM is made publicly available at https://github.com/mazurowski-lab/segment-anything-medical-evaluation.


Assuntos
Neoplasias Encefálicas , Humanos , S-Adenosilmetionina , Tomografia Computadorizada por Raios X
18.
IEEE Trans Med Imaging ; 42(12): 3860-3870, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37695965

RESUMO

Anomaly detection (AD) aims to determine if an instance has properties different from those seen in normal cases. The success of this technique depends on how well a neural network learns from normal instances. We observe that the learning difficulty scales exponentially with the input resolution, making it infeasible to apply AD to high-resolution images. Resizing them to a lower resolution is a compromising solution and does not align with clinical practice where the diagnosis could depend on image details. In this work, we propose to train the network and perform inference at the patch level, through the sliding window algorithm. This simple operation allows the network to receive high-resolution images but introduces additional training difficulties, including inconsistent image structure and higher variance. We address these concerns by setting the network's objective to learn augmentation-invariant features. We further study the augmentation function in the context of medical imaging. In particular, we observe that the resizing operation, a key augmentation in general computer vision literature, is detrimental to detection accuracy, and the inverting operation can be beneficial. We also propose a new module that encourages the network to learn from adjacent patches to boost detection performance. Extensive experiments are conducted on breast tomosynthesis and chest X-ray datasets and our method improves 8.03% and 5.66% AUC on image-level classification respectively over the current leading techniques. The experimental results demonstrate the effectiveness of our approach.


Assuntos
Algoritmos , Redes Neurais de Computação , Aprendizado de Máquina Supervisionado
19.
Infect Drug Resist ; 16: 6807-6820, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37904831

RESUMO

Purpose: This paper aims to investigate the effect of Tounong San (TNS), a well-known traditional Chinese medicine prescription for suppurative infections, on the immune function. Methods: A suppurative infection model was established by injecting Staphylococcus aureus into subcutaneous tissue on the backs of rats. The expressions of CD68, CD163, CD31 and MPO in abscess tissues, phagocytosis rate and reactive oxygen species (ROS) of neutrophils in blood, phagocytosis function of peritoneal macrophages, and proliferation of blood lymphocytes, expression of IL-1, IL-6, CH50, TNF-α, IFN-γ, IgG, IgM in serum were detected at different time points. Results: On the 3rd day of medication, fibrinogen wrapped around the abscesses was visible in TNS groups, with an increase in new blood vessels and the expression of a large number of macrophages and neutrophils. On the 6th day, the pus of TNS groups diminished, and the number of new blood vessels reached its peak. On the 9th day, the abscesses disappeared in TNS groups, fewer new blood vessels, macrophages, and neutrophils were expressed, and more fibrocytes appeared and filled the original pus cavities. On the 3rd and 9th day of medication, the phagocytic rates of neutrophils and macrophages were significantly improved in TNS group, and the ROS content of neutrophils was increased on the 9th day. TNS has no effect on lymphocyte proliferation in vitro, but it can regulate the secretion of IgG and IgM by lymphocytes. TNS increases the level of IL-1, decreases the levels of IL-6 and TNF-α, and regulates the expressions of IFN-γ and CH50 in two ways. Conclusion: TNS can form fibrinogen-wrapped pus to prevent bacterial infection from going deeper, and to improve the phagocytic function of phagocytes, the secretion of lymphocytes, and the defense function of the complement system. Therefore, it is a competitive drug for the treatment of suppurative diseases.

20.
Environ Int ; 172: 107762, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36689865

RESUMO

Estuarine wetlands with high organic carbon (OC) accumulation rates due to their high plant biomass and interception of tide-derived OC are generally considered as large CO2 sinks. However, our previous study found that tidal OC input seems to stimulate soil CO2 emissions, potentially weakening CO2 sequestration in estuarine wetlands. To further verify this phenomenon, we first established a structural equation model, which confirmed a positive correlation between tidal OC input and soil organic carbon (SOC) and soil respiration. We then performed trace analysis to determine the stability of SOC derived from different sources and its effect on soil CO2 emissions by analyzing the input and retention of OC derived from tides and plants in the Yangtze Estuary wetlands. From upstream to downstream, as tidal OC input decreased, the relative retention ratio of the tidal OC in wetland soil increased from 1.259 to 2.148, whereas the relative retention ratio of plant OC in the soil decreased from 61.5% to 14.8%. Our findings indicated that the degradability of tidal OC was higher upstream than that downstream, but both inhibited plant OC degradation, thus providing an important reason for the higher CO2 emissions upstream of wetlands (with higher tidal OC input). In addition, the primarily contributor to CO2 (δ13) emissions' transforming from plant SOC (81.35%) to tidal SOC (91.18%) was an increase in organic matter input from the tide in a microcosm system. Consequently, a higher CO2 output than CO2 input (plant OC) due to the ready degradation of tidal OC consequently weakens the CO2 sequestration capacity of the estuarine wetlands. This phenomenon is cause for concern regarding the CO2 sink function of estuarine wetlands intercepting large amounts of organic matter.


Assuntos
Carbono , Áreas Alagadas , Carbono/análise , Dióxido de Carbono , Solo/química , Biomassa , Plantas , Sequestro de Carbono , China
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