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1.
Nanotechnology ; 35(33)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38744256

RESUMO

Secondary battery as an efficient energy conversion device has been highly attractive for alleviating the energy crisis and environmental pollution. Hierarchical porous carbon (HPC) materials with multiple sizes pore channels are considered as promising materials for energy conversion and storage applications, due to their high specific surface area and excellent electrical conductivity. Although many reviews have reported on carbon materials for different fields, systematic summaries about HPC materials for lithium storage are still rare. In this review, we first summarize the main preparation methods of HPC materials, including hard template method, soft template method, and template-free method. The modification methods including porosity and morphology tuning, heteroatom doping, and multiphase composites are introduced systematically. Then, the recent advances in HPC materials on lithium storage are summarized. Finally, we outline the challenges and future perspectives for the application of HPC materials in lithium storage.

2.
Pacing Clin Electrophysiol ; 47(1): 58-65, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38010824

RESUMO

BACKGROUND: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) is reported to reduce incident atrial fibrillation (AF) in patients with or without diabetes; however, its cardiovascular (CV) benefit for AF patients remains unclear. SS AIMS: To investigate the effect of SGLT2i on the incidence of CV events in patients with AF. METHODS: Six randomized controlled trials (RCTs) assessing the effects of SGLT2i on CV outcomes in patients with or without AF were included (PROSPERO: CRD 42023431535). The primary endpoint was the composite outcome of heart failure (HF) hospitalization and CV death. Additionally, we assessed the effects of treatment in prespecified subgroups on HF hospitalization, CV death, and all-cause mortality. RESULTS: Among 38,529 participants from all trials, 5018 patients with AF were treated with SGLT2i. The follow-up period of these trials ranged from 2.3 to 3.3 years. SGLT2i treatment was significantly associated with the risk reduction of primary endpoint in patients with AF (risk ratio [RR] 0.81, 95% confidence interval [CI] 0.74-0.88; p < 0.001), consistent with the finding in the general population (p for interaction = 0.76). SGLT2i was also associated with a consistent reduction in the risk of HF hospitalization in patients with AF (RR 0.76, 95% CI 0.69-0.84; p < 0.001) or not (RR 0.72, 95% CI 0.64-0.80; p < 0.0001), with no statistical difference between them (p for interaction = 0.41). Meta-regression further revealed no significant association between the prevalence of HF with reduced ejection fraction or diabetes and the effect size of SGLT2i. CONCLUSIONS: The treatment effects of SGLT2i were associated with a lower incidence of CV events, especially HF hospitalization, in patients with AF.


Assuntos
Fibrilação Atrial , Diabetes Mellitus , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Fibrilação Atrial/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia
3.
Pacing Clin Electrophysiol ; 47(4): 511-517, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38407298

RESUMO

BACKGROUND: Wearable devices based on the PPG algorithm can detect atrial fibrillation (AF) effectively. However, further investigation of its application on long-term, continuous monitoring of AF burden is warranted. METHOD: The performance of a smartwatch with continuous photoplethysmography (PPG) and PPG-based algorithms for AF burden estimation was evaluated in a prospective study enrolling AF patients admitted to Beijing Anzhen Hospital for catheter ablation from September to November 2022. A continuous Electrocardiograph patch (ECG) was used as the reference device to validate algorithm performance for AF detection in 30-s intervals. RESULTS: A total of 578669 non-overlapping 30-s intervals for PPG and ECG each from 245 eligible patients were generated. An interval-level sensitivity of PPG was 96.3% (95% CI 96.2%-96.4%), and specificity was 99.5% (95% CI 99.5%-99.6%) for the estimation of AF burden. AF burden estimation by PPG was highly correlated with AF burden calculated by ECG via Pearson correlation coefficient (R2 = 0.996) with a mean difference of -0.59 (95% limits of agreement, -7.9% to 6.7%). The subgroup study showed the robust performance of the algorithm in different subgroups, including heart rate and different hours of the day. CONCLUSION: Our results showed the smartwatch with an algorithm-based PPG monitor has good accuracy and stability in continuously monitoring AF burden compared with ECG patch monitors, indicating its potential for diagnosing and managing AF.


Assuntos
Fibrilação Atrial , Humanos , Fibrilação Atrial/diagnóstico , Fotopletismografia/métodos , Estudos Prospectivos , Sensibilidade e Especificidade , Algoritmos , Eletrocardiografia/métodos
4.
Biomacromolecules ; 24(12): 5859-5870, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-38015033

RESUMO

Nano scale topography scaffold is more bioactive and biomimetic than smooth fiber topographies. Tendon stem cells (TSCs) play important roles in the tendinogenesis of tendon tissue engineering, but the effects and mechanisms of nano topography on TSC behavior are still unclear. This study determined whether the morphology, proliferation, cytoskeleton, and differentiation of TSCs are affected by topography of scaffold in vitro. The porous PA56 scaffolds were prepared with different concentration ratios of glycerol as the molecular template by electrospinning. Its topological characteristics, hydrophilicity, and degradation properties varied with glycerol proportion and movement rate of the receiving plate. Porous fibers promoted the proliferation of TSCs and the number of TSCs varied with topography. Although there was no significant difference due to the small sample size, the number of pseudopodia and cell polarizability still showed differences among different topographies. The morphology of actin cytoskeleton of TSCs showed difference among cultured on porous fibers, smooth fibers, and in culture media with no fiber, suggesting the orientation growth of cells on porous fiber. Moreover, porous fibers promoted teno-lineage differentiation of TSCs by upregulating tendon-specific gene expression. These findings provide evidence that nano porous topography scaffold promotes TSC proliferation, cytoskeleton orientation, and tenogenic differentiation.


Assuntos
Glicerol , Nanoporos , Tendões , Células-Tronco , Engenharia Tecidual , Diferenciação Celular , Proliferação de Células
5.
Environ Sci Technol ; 57(17): 6965-6974, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37083304

RESUMO

Multiphase oxidative aging is a ubiquitous process for atmospheric organic aerosols (OA). But its kinetics was often found to be slow in previous laboratory studies where high hydroxyl radical concentrations ([•OH]) were used. In this study, we performed heterogeneous oxidation experiments of several model OA systems under varied aging timescales and gas-phase [•OH]. Our results suggest that OA heterogeneous oxidation may be 2-3 orders of magnitude faster when [•OH] is decreased from typical laboratory flow tube conditions to atmospheric levels. Direct laboratory mass spectrometry measurements coupled with kinetic simulations suggest that an intermolecular autoxidation mechanism mediated by particle-phase peroxy radicals greatly accelerates OA oxidation, with enhanced formation of organic hydroperoxides, alcohols, and fragmentation products. With autoxidation, we estimate that the OA oxidation timescale in the atmosphere may be from less than a day to several days. Thus, OA oxidative aging can have greater atmospheric impacts than previously expected. Furthermore, our findings reveal the nature of heterogeneous aerosol oxidation chemistry in the atmosphere and help improve the understanding and prediction of atmospheric OA aging and composition evolution.


Assuntos
Atmosfera , Atmosfera/análise , Atmosfera/química , Aerossóis/análise , Oxirredução
6.
Opt Express ; 30(11): 18836-18844, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221675

RESUMO

In this paper, a hollow-core anti-resonant fiber (HC-ARF) based light-induced thermoelastic spectroscopy (LITES) sensor is reported. A custom-made silica-based HC-ARF with length of 75 cm was used as light medium and gas cell. Compared to a traditional multi-pass cell (MPC), the using of HC-ARF is advantageous for reducing the sensor size and easing the optical alignment. A quartz tuning fork (QTF) with a resonant frequency of 32766.20 Hz and quality factor of 12364.20 was adopted as the thermoelastic detector. Acetylene (C2H2) and carbon monoxide (CO) with absorption lines located at 6534.37 cm-1 (1530.37 nm) and 6380.30 cm-1 (1567.32 nm) were chosen as the target gas to verify such HC-ARF based LITES sensor performance. It was found that this HC-ARF based LITES sensor exhibits excellent linearity response to the analyte concentrations. The minimum detection limit (MDL) for C2H2 and CO detections were measured as 4.75 ppm and 1704 ppm, respectively. The MDL for such HC-ARF based LITES sensor can be further improved by using a HC-ARF with long length or choosing an absorption line with strong strength.

7.
Environ Sci Technol ; 56(22): 15337-15346, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36282674

RESUMO

Limonene is an abundant monoterpene released into the atmosphere via biogenic emissions and biomass burning. However, the atmospheric oxidation and secondary organic aerosol (SOA) formation mechanisms of limonene, especially during nighttime, remain largely understudied. In this work, limonene was oxidized synergistically by ozone (O3) and nitrate radicals (NO3) in a flow tube reactor and a continuous flow stirred tank reactor. Upon oxidation, many highly oxidized organic nitrates and nitrooxy peroxy radicals (RO2) were observed in the gas phase within 1 min. Combining quantum chemical calculations with kinetic simulations, we found that the primary nitrooxy RO2 (C10H16NO5) through NO3 addition at the more substituted endocyclic double bond and at the exocyclic double bond (previously considered as minor pathways) can undergo autoxidation with rate constants of around 0.02 and 20 s-1 at 298 K, respectively. These pathways could explain a major portion of the observed highly oxidized organic nitrates. In the SOA, highly oxidized mono- and dinitrates (e.g., C10H17NO7-8 and C10H16,18N2O8-10) make up a significant contribution, highlighting nitrooxy RO2 autoxidation and sequential NO3 oxidation of limonene. The same organic nitrates are also observed in ambient aerosol during biomass burning and nighttime in the southeastern United States. Therefore, the present work provides new insights into the nighttime oxidation of limonene and SOA formation in the atmosphere.


Assuntos
Poluentes Atmosféricos , Ozônio , Limoneno , Nitratos/química , Poluentes Atmosféricos/análise , Aerossóis/química , Ozônio/química , Compostos Orgânicos , Óxidos de Nitrogênio
8.
Environ Sci Technol ; 56(12): 7761-7770, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35675110

RESUMO

Nitrogen-containing heterocyclic volatile organic compounds (VOCs) are important components of wildfire emissions that are readily reactive toward nitrate radicals (NO3) during nighttime, but the oxidation mechanism and the potential formation of secondary organic aerosol (SOA) and brown carbon (BrC) are unclear. Here, NO3 oxidation of three nitrogen-containing heterocyclic VOCs, pyrrole, 1-methylyrrole (1-MP), and 2-methylpyrrole (2-MP), was investigated in chamber experiments to determine the effect of precursor structures on SOA and BrC formation. The SOA chemical compositions and the optical properties were analyzed using a suite of online and offline instrumentation. Dinitro- and trinitro-products were found to be the dominant SOA constituents from pyrrole and 2-MP, but not observed from 1-MP. Furthermore, the SOA from 2-MP and pyrrole showed strong light absorption, while that from 1-MP were mostly scattering. From these results, we propose that NO3-initiated hydrogen abstraction from the 1-position in pyrrole and 2-MP followed by radical shift and NO2 addition leads to light-absorbing nitroaromatic products. In the absence of a 1-position hydrogen, NO3 addition likely dominates the 1-MP chemistry. We also estimate that the total SOA mass and light absorption from pyrrole and 2-MP are comparable to those from phenolic VOCs and toluene in biomass burning, underscoring the importance of considering nighttime oxidation of pyrrole and methylpyrroles in air quality and climate models.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Aerossóis/química , Poluentes Atmosféricos/análise , Carbono , Hidrogênio , Nitratos , Nitrogênio , Óxidos de Nitrogênio , Pirróis
9.
Sensors (Basel) ; 22(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36236522

RESUMO

Unmanned ground vehicles (UGVs) are making more and more progress in many application scenarios in recent years, such as exploring unknown wild terrain, working in precision agriculture and serving in emergency rescue. Due to the complex ground conditions and changeable surroundings of these unstructured environments, it is challenging for these UGVs to obtain robust and accurate state estimations by using sensor fusion odometry without prior perception and optimization for specific scenarios. In this paper, based on an error-state Kalman filter (ESKF) fusion model, we propose a robust lidar-inertial odometry with a novel ground condition perception and optimization algorithm specifically designed for UGVs. The probability distribution gained from the raw inertial measurement unit (IMU) measurements during a certain time period and the state estimation of ESKF were both utilized to evaluate the flatness of ground conditions in real-time; then, by analyzing the relationship between the current ground condition and the accuracy of the state estimation, the tightly coupled lidar-inertial odometry was dynamically optimized further by adjusting the related parameters of the processing algorithm of the lidar points to obtain robust and accurate ego-motion state estimations of UGVs. The method was validated in various types of environments with changeable ground conditions, and the robustness and accuracy are shown through the consistent accurate state estimation in different ground conditions compared with the state-of-art lidar-inertial odometry systems.


Assuntos
Algoritmos , Percepção , Movimento (Física) , Probabilidade , Fatores de Tempo
10.
Environ Sci Technol ; 55(10): 6700-6709, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33913707

RESUMO

α-Pinene ozonolysis is a key process that impacts the formation of new particles and secondary organic aerosol (SOA) in the atmosphere. The mechanistic understanding of this chemistry has been inconclusive despite extensive research, hindering accurate simulations of atmospheric processes. In this work, we examine the ozonolysis of two synthesized unsaturated carbonyl isomers (C11H18O) which separately produce the two Criegee intermediates (CIs) that would form simultaneously in α-pinene ozonolysis. Direct gas-phase measurements of peroxy radicals (RO2) from flowtube ozonolysis experiments by an iodide-adduct chemical ionization mass spectrometer suggest that the initial C10H15O4· RO2 from the CI with a terminal methyl ketone undergo autoxidation 20-fold faster than the CI with a terminal aldehyde and always outcompete the bimolecular reactions under typical laboratory and atmospheric conditions. These results provide experimental constraints on the detailed RO2 autoxidation mechanisms for understanding new particle formation in the atmosphere. Further, isomer-resolved characterization of the SOA formed from a continuous-flow stirred tank reactor using ion mobility spectrometry mass spectrometry suggests that the two structurally different CIs predominantly and unexpectedly form constituents with identical structures. These results open up possibilities of diverse isomerization pathways that the two CIs may undergo that form mutual products to a large extent toward their way forming the SOA. This work highlights new insights into α-pinene ozonolysis pathways and call for future studies to uncover the detailed mechanisms.


Assuntos
Poluentes Atmosféricos , Ozônio , Aerossóis , Monoterpenos Bicíclicos , Monoterpenos
11.
Neurosurg Rev ; 44(6): 3197-3207, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33864525

RESUMO

Few studies have examined the postoperative hemorrhage rate of cerebral arteriovenous malformations (AVMs) treated by embolization prior to stereotactic radiosurgery. The objective of this analysis was to compare the postoperative hemorrhage rate between AVMs treated with and those treated without preradiosurgery embolization. A systematic search of the PubMed and Embase databases was performed with no restriction on the publication period. Based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies with sufficient baseline and outcome data. The analysis was performed using Comprehensive Meta-Analysis (CMA) 2.0. Eleven studies comprising 2591 patients were eligible for analysis. There was no significant difference in the postoperative hemorrhage rate between patients who had undergone embolization followed by SRS and those who had undergone SRS alone (OR 1.140, 95% CI 0.851-1.526, p = 0.38). The obliteration rate was significantly lower in the E + SRS group than in the SRS group (OR 0.586, 95% CI 0.398-0.863, p = 0.007). No significant difference in permanent neurological deficits was identified between patients who had undergone embolization followed by SRS and those who had undergone SRS alone (OR 1.175, 95% CI 0.626-2.206, p = 0.616). Available data suggested that preradiosurgery embolization did not reduce the postoperative hemorrhage rate and resulted in a significantly lower obliteration rate than treatment with SRS alone.


Assuntos
Embolização Terapêutica , Malformações Arteriovenosas Intracranianas , Radiocirurgia , Embolização Terapêutica/efeitos adversos , Seguimentos , Humanos , Malformações Arteriovenosas Intracranianas/cirurgia , Hemorragia Pós-Operatória , Estudos Retrospectivos , Resultado do Tratamento
12.
Stroke ; 51(11): 3250-3263, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32921259

RESUMO

BACKGROUND AND PURPOSE: Although endovascular treatment (EVT) for acute ischemic stroke is classified as I evidence, outcomes after EVT in real-world practice appear to be less superior than those in randomized clinical trials (RCTs). Additionally, the effect of EVT is unclear compared with medical treatment (MT) for patients with mild symptoms defined by National Institutes of Health Stroke Scale score <6 or with severe symptoms defined by Alberta Stroke Program Early CT Score <6. METHODS: Literatures were searched in big databases and major meetings from December 6, 2009, to December 6, 2019, including RCTs and observational studies comparing EVT against MT for patients with acute ischemic stroke. Observational studies were precategorized into 3 groups based on imaging data on admission: mild stroke group with National Institutes of Health Stroke Scale score <6, severe stroke group with Alberta Stroke Program Early CT Score <6 or ischemic core ≥50 mL, and normal stroke group for all others. Outcome was measured as modified Rankin Scale score of 0 to 2, mortality at 90 days, and symptomatic intracranial hemorrhage (sICH) at 24 hours. RESULTS: Fifteen RCTs (n=3694) and 37 observational studies (n=9090) were included. EVT was associated with higher modified Rankin Scale 0 to 2 rate and lower mortality in RCTs and normal stroke group, whereas EVT was associated with higher sICH rate in normal stroke group, and no difference of sICH rate appeared between EVT and MT in RCTs. In severe stroke group, EVT was associated with higher modified Rankin Scale 0 to 2 rate and lower mortality, whereas no difference of sICH rate was found. In mild stroke group, there was no difference in modified Rankin Scale 0 to 2 rate between EVT and MT, whereas EVT was associated with higher mortality and sICH rate. CONCLUSIONS: Evidence from RCTs and observational studies supports the use of EVT as the first-line choice for eligible patients corresponding to the latest guideline. For patients with Alberta Stroke Program Early CT Score <6, EVT showed superiority over MT, also in line with the guidelines. On the contrary to the guideline, our data do not support EVT for patients with National Institutes of Health Stroke Scale score <6.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico/cirurgia , Trombectomia , Humanos , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/fisiopatologia , Mortalidade , Estudos Observacionais como Assunto , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia Trombolítica , Resultado do Tratamento
13.
Chem Res Toxicol ; 33(8): 2157-2163, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32618192

RESUMO

Recent reports have linked severe lung injuries and deaths to the use of e-cigarettes and vaping products. Nevertheless, the causal relationship between exposure to vaping emissions and the observed health outcomes remains to be elucidated. Through chemical and toxicological characterization of vaping emission products, this study demonstrates that during vaping processes, changes in chemical composition of several commonly used vape juice diluents (also known as cutting agents) lead to the formation of toxic byproducts, including quinones, carbonyls, esters, and alkyl alcohols. The resulting vaping emission condensates cause inhibited cell proliferation and enhanced cytotoxicity in human airway epithelial cells. Notably, substantial formation of the duroquinone and durohydroquinone redox couple was observed in the vaping emissions from vitamin E acetate, which may be linked to acute oxidative stress and lung injuries reported by previous studies. These findings provide an improved molecular understanding and highlight the significant role of toxic byproducts in vaping-associated health effects.


Assuntos
Benzoquinonas/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Hidroquinonas/efeitos adversos , Lesão Pulmonar/induzido quimicamente , Vaping/efeitos adversos , Vitamina E/efeitos adversos , Benzoquinonas/química , Benzoquinonas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Hidroquinonas/química , Hidroquinonas/metabolismo , Vitamina E/química , Vitamina E/metabolismo
14.
J Stroke Cerebrovasc Dis ; 29(10): 105122, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32912548

RESUMO

BACKGROUND: Endovascular treatment (EVT) is merely recommended as class of recommendation IIb for patients with ASPECTS <6 according to the American Heart Association guideline 2019. In addition, the best determined imaging technique for EVT in patient with ASPECTS<6 remains unknown. The objective of this study was to define the safety and efficacy of EVT for patients with ASPECTS<6 and investigate the superiority between MRI and CT for patient selection. METHODS: A systematic search of PubMed, EMBASE, The Cochrane Library and other additional sources was performed for studies published with no publication period. Our study was conducted corresponding to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRIMA) guidelines. The analysis was performed using the Comprehensive Meta-Analysis (CMA) 2.0. RESULTS: Five studies reporting data from 844 participants were included in our analysis according to the inclusion criteria. Consequently, EVT was associated with statistically significant higher functional independence compared with MT (OR 5.401, 95% CI 3.227-9.041). Whereas EVT was found to be related to lower mortality compared with MT based on eligible data (OR 0.461, 95% CI 0.329-0.647). No significant difference was identified in sICH between EVT and MT (OR 1.075, 95% CI 0.452-2.558). CONCLUSION: According to the results of our study, we suggested that EVT is a preferred therapy in ACS patients with ASPECTS<6 in consideration of efficacy and safety. Furthermore, MRI did not show superiority over CT as no statistical difference was detected in all subgroups.


Assuntos
Isquemia Encefálica/terapia , Circulação Cerebrovascular , Procedimentos Endovasculares , Hemorragias Intracranianas/terapia , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/mortalidade , Isquemia Encefálica/fisiopatologia , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/mortalidade , Hemorragias Intracranianas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
15.
J Phys Chem A ; 123(50): 10782-10792, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31765152

RESUMO

Oxidative aging of atmospheric organic aerosols (OA) substantially modifies their chemical compositions, physical properties, and hence the various environmental impacts. Here, we report observations of a previously unrecognized process leading to dimer formation during heterogeneous •OH-initiated oxidative aging of oxygenated OA. Isomer-resolved ion mobility mass spectrometry measurements and reaction-diffusion kinetic simulations are in good agreement, elucidating new mechanisms of dimerization by organic radical (i.e., peroxy and alkoxy radicals) cross reactions using glutaric acid as a surrogate oxygenated OA. These radical reactions are predicted to occur more prominently near the gas-particle interface following oxidation, especially in diffusion-limited viscous OA particles. Chemical structure analysis shows that esters dominate the detected dimers, followed by organic peroxides and ethers, highlighting the importance of acyl peroxy and acyloxy radicals. Simulations suggest that the reported dimer formation through the new interfacial mechanism could be appreciable under both laboratory and ambient conditions. Therefore, the dimers that are formed and enriched at the gas-particle interface are expected to play a crucial role in the effective reactivity, volatility, viscosity, and hygroscopicity of aged OA particles.

16.
Opt Express ; 26(17): 21606-21614, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30130864

RESUMO

In this paper, the optical fiber Fabry-Perot (F-P) interferometer based on phase-shifting technique and birefringence crystals is proposed and demonstrated. We use the characteristics of birefringence and four birefringence crystals with different thicknesses to obtain the quadrature phase-shifted signals, which are demodulated by phase-shifting technique. Two types of sensing interferometers are used in the experiment. One is the optical fiber F-P sensor and the other is composed of the fiber end face and the glass surface fixed on the nanopositioning stage. The experimental results show that the normalized standard deviation (SD) of the calibration microphone centerline is 1.97 and 2.63 times larger than the optical fiber F-P interferometer under the sinusoidal sonic signals of 21 kHz and 40 kHz, and the interferometer is effective in avoiding phase ambiguity. The proposed interferometer has high stability and can adapt to a larger measurement range.

17.
Heliyon ; 10(4): e25250, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384557

RESUMO

The excellent image-generation ability of generative adversarial networks (GANs) has been widely used. However, training a GAN requires large-scale data support, which hinders in-depth development. Therefore, the research on stable training of GANs under limited data conditions is helpful to further expand the application scenarios. To solve this problem, a new network based on a dual-ways discriminator structure is designed, used to eliminate the problem that a single discriminator model is prone to overfitting under the condition of limited data. Then, the problem that the traditional data augmentation strategy is limited to pixel space and lacks attention to the overall structure and contour of the image is analyzed. An adaptive dynamic data augmentation strategy based on the Laplace convolution kernel is proposed from the frequency domain space, which realizes the purpose of implicitly increasing the training data in the training process. This new designed module improves the performance of the generative adversarial network. Through extensive experiments, it was confirmed that the new network, named FD-GAN, achieved prefer image generation ability, and its Fid score reached 4.58, 12.007, and 10.382 in the AFHQ-Cat, AFHQ-Dog, and TankDataSet datasets, respectively.

18.
Prog Biophys Mol Biol ; 187: 36-50, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280492

RESUMO

Tissue repair and regeneration is a vital biological process in organisms, which is influenced by various internal mechanisms and microenvironments. Pulsed electromagnetic fields (PEMFs) are becoming a potential medical technology due to its advantages of effectiveness and non-invasiveness. Numerous studies have demonstrated that PEMFs can stimulate stem cell proliferation and differentiation, regulate inflammatory reactions, accelerate wound healing, which is of great significance for tissue regeneration and repair, providing a solid basis for enlarging its clinical application. However, some important issues such as optimal parameter system and potential deep mechanisms remain to be resolved due to PEMFs window effect and biological complexity. Thus, it is of great importance to comprehensively summarizing and analyzing the literature related to the biological effects of PEMFs in tissue regeneration and repair. This review expounded the biological effects of PEMFs on stem cells, inflammation response, wound healing and musculoskeletal disorders in order to improve the application value of PEMFs in medicine. It is believed that with the continuous exploration of biological effects of PEMFs, it will be applied increasingly widely to tissue repair and other diseases.


Assuntos
Campos Eletromagnéticos , Células-Tronco Mesenquimais , Diferenciação Celular , Cicatrização , Células-Tronco
19.
Front Endocrinol (Lausanne) ; 15: 1340644, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38405152

RESUMO

Background: Non-alcoholic fatty liver disease (NAFLD) is increasingly observed in non-obese individuals. The ZJU (Zhejiang University) index has been established as a new and efficient tool for detecting NAFLD, but the relationship between the ZJU index and NAFLD within non-obese individuals still remains unclear. Methods: A post-hoc evaluation was undertaken using data from a health assessment database by the Wenzhou Medical Center. The participants were divided into four groups based on the quartile of the ZJU Index. Cox proportional hazards regression, Kaplan-Meier analysis and tests for linear trends were used to evaluate the relationship between the ZJU index and NAFLD incidence. Subgroup analysis was conducted to test the consistency of the correlation between ZJU and NAFLD in subsgroups. Receiver operative characteristic (ROC) curve analysis was performed to evaluate the predictive performance of the ZJU index, compared with the Atherogenic index of plasma (AIP) and Remnant lipoprotein cholesterol (RLP-C) index. Results: A total of 12,127 were included in this study, and 2,147 participants (17.7%) developed NAFLD in 5 years follow-up. Participants in higher ZJU quartiles tended to be female and have higher liver enzymes (including ALP, GGT, ALT, AST), GLU, TC, TG, LDL and higher NAFLD risk. Hazard Ratios (HR) and 95% confidence intervals (CI) for new-onset NAFLD in Q2, Q3, and Q4 were 3.67(2.43 to 5.55), 9.82(6.67 to 14.45), and 21.67(14.82 to 31.69) respectively in the fully adjusted model 3. With increased ZJU index, the cumulative new-onset NAFLD gradually increased. Significant linear associations were observed between the ZJU index and new-onset NAFLD (p for trend all<0.001). In the subgroup analysis, we noted a significant interaction in sex, with HRs of 3.27 (2.81, 3.80) in female and 2.41 (2.21, 2.63) in male (P for interaction<0.01). The ZJU index outperformed other indices with an area under the curve (AUC) of 0.823, followed by AIP (AUC=0.747) and RLP-C (AUC=0.668). Conclusion: The ZJU index emerges as a promising tool for predicting NAFLD risk in non-obese individuals, outperforming other existing parameters including AIP and RLP-C. This could potentially aid in early detection and intervention in this specific demographic.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Feminino , Humanos , Masculino , Povo Asiático , China/epidemiologia , Incidência , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Prospectivos , Indicadores Básicos de Saúde
20.
J Am Coll Cardiol ; 83(20): 1957-1969, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38749614

RESUMO

BACKGROUND: It is still unclear whether small left ventricle (LV) is an adverse structural prognostic feature in patients with atrial fibrillation (AF). OBJECTIVES: The purpose of this study was to evaluate the association between small LV and risk of cardiovascular events in AF population. METHODS: From the China-AF registry, 7,764 patients with AF were enrolled and divided into groups with normal, small, and large LV size based on left ventricular end-diastolic dimension (LVEDD) measurement per the American Society of Echocardiography references. Cox models were used to assess the association between LV size or LVEDD with composite cardiovascular events (cardiovascular death, ischemic stroke or systemic embolism, or major bleeding). RESULTS: There were 308 (4.0%) participants assessed with small LV who were older, with lower body mass and blood pressure, and fewer comorbidities, and 429 (5.5%) were identified with large LV. Compared with the normal LV group, small LV and large LV were significantly associated with higher incidence of composite cardiovascular events (adjusted HR [aHR]: 1.54 [95% CI: 1.07-2.20] for small LV; aHR: 1.36 [95% CI: 1.02-1.81] for large LV) and cardiovascular death (aHR: 1.94 [95% CI: 1.14-3.28] for small LV; aHR: 1.83 [95% CI: 1.24-2.69] for large LV). Small LV was also associated with increased risk of major bleeding [aHR: 2.21 [95% CI: 1.01-4.86]). A U-shaped relationship between LVEDD and composite cardiovascular events was identified (Pnonlinear < 0.001). CONCLUSIONS: In a prospective AF cohort, small LV was independently associated with an increased risk of cardiovascular events, which needed consideration in risk stratification and management for patients with AF. (ChiCTR-OCH-13003729).


Assuntos
Fibrilação Atrial , Ventrículos do Coração , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , China/epidemiologia , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Tamanho do Órgão , Estudos Prospectivos , Sistema de Registros , Medição de Risco/métodos , Fatores de Risco
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