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1.
Opt Express ; 32(6): 9245-9254, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571163

RESUMO

As for the photonic interconnection based on the multiple-lane intensity modulation direct detection (IM-DD) transmission, both intra-channel inter-symbol-interference (ISI) originating from bandwidth constraint, and inter-channel performance discrepancy emerging from inter-channel component differences are the major bottleneck for the throughput enhancement. Here, we propose a pairwise Tomlinson-Harshima precoding (P-THP) scheme, in order to simultaneously deal with both intra-channel ISI and inter-channel performance discrepancy. The effective function of the proposed P-THP scheme is experimentally evaluated by transmitting 4-channel 81-GBaud PAM4 signals over 2 km standard single-mode fiber (SSMF). Compared with the conventional scheme with only applying THP on individual wavelength channel, the required optical received power (ROP) under the back-to-back (B2B) transmission can be reduced by 0.75∼1 dB with the help of proposed P-THP in different experimental component configurations, at the 7% hard decision forward error correction (HD-FEC) threshold of BER = 3.8 × 10-3. After the 2 km SSMF transmission, only the use of proposed P-THP can guarantee to reach the designated HD-FEC threshold, leading to a net rate of >600 Gbit/s.

2.
Opt Express ; 32(6): 9332-9342, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571170

RESUMO

We theoretically and experimentally verify that, the bidirectional hybrid-mode pumping scheme can address the optimization problem of trade-off between high gain and low differential modal gain (DMG) of four-mode erbium-doped fiber amplifier (4M-EDFA), in comparison with traditional both forward and backward hybrid-mode pumping scheme. It is noticed that, when the total pump power is fixed, the bidirectional hybrid-mode pumping scheme can not only achieve higher gain, but also suppress DMG due to different overlap integrals for the forward and backward pumping schemes. The bidirectional hybrid-mode pumped 4M-EDFA is developed with the forward pumping at LP02 mode and the backward pumping at LP21 mode, under a pump power ratio of 30%:70%. Thus, we can achieve an average gain of up to 21.16 dB and a low DMG of 0.43 dB at 1550 nm, and an average gain of up to 20.64 dB with a DMG of less than 1.6 dB over the C-band. In particular, the bidirectional hybrid-mode pumping scheme allows us to tailor the gain characteristics of the few-mode erbium-doped fiber amplifiers (FM-EDFAs), by adjusting the power ratio between forward and backward pumps.

3.
Mikrochim Acta ; 191(5): 232, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565740

RESUMO

A novel ternary heterojunction material In2O3/In2S3/ZnIn2S4 was synthesized, and a photoelectrochemical sensor was fabricated for the non-invasive test of dopamine (DA) in sweat. In2O3 multihollow microtubules were synthesized and then In2S3 was formed on their surface to construct a type-I heterojunction between In2S3 and In2O3. ZnIn2S4 was further introduced to form a Z-scheme heterojunction between In2S3/ZnIn2S4. Under photoexcitation, the photogenerated holes of In2O3 transferred to the valence band of In2S3, superimposed with the holes produced by In2S3, leads to a significantly higher photocatalytic oxidation capacity of In2O3/In2S3/ZnIn2S4 ternary composites than that of In2O3/In2S3. The Z-scheme heterojunction accelerates the transfer of photogenerated electrons accumulated on the type-I heterojunction. In the presence of DA, it is rapidly oxidized into polydopamine (PDA) by In2O3/In2S3, and the benzoquinone groups of PDA compete for the photogenerated electrons to reduce the current in the external circuit, whereby DA determination is achieved. Owing to the combination of type-I and Z-scheme heterojunction, the sensor showed extremely high sensitivity, with a detection limit of 3.94 × 10-12 mol/L. It is one of the most sensitive methods for DA detection reported and has been applied to the determination of DA in human sweat.


Assuntos
Dopamina , Suor , Humanos , Elétrons
4.
Int J Environ Health Res ; : 1-12, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647234

RESUMO

The relationship between fine particulate matter (PM2.5) and blood pressure (BP) is a controversial issue. We conducted a two-sample Mendelian randomization (MR) analysis and identified 58 genome-wide significant single-nucleotide polymorphisms associated with PM2.5 as instrument variables. Inverse-variance weighted (IVW) was used as the primary analysis approach. MR-Egger, weighted median, simple model, and weighted model methods were selected for quality control. We found a significant negative causal association of higher genetically predicted PM2.5 levels with lower systolic BP (SBP), while no causal relationship was identified between PM2.5 and diastolic BP (DBP). For each 1 standard deviation increase in genetically predicted PM2.5 levels, the beta value (95% CI) of SBP was -0.14 (-0.25, -0.03) for IVW (p=0.02), and -0.13 (-0.22, -0.04) for weighted median (p=0.005). Increased PM2.5 concentrations can lead to decreased SBP levels. Our findings provided novel insights into the controversial topic on the causal relationship between PM2.5 and BP.

5.
BMC Public Health ; 24(1): 1071, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632605

RESUMO

BACKGROUND: Inter-leg systolic blood pressure difference (ILSBPD) has emerged as a novel cardiovascular risk factor. This study aims to investigate the predictive value of ILSBPD on all-cause and cardiovascular mortality in general population. METHODS: We combined three cycles (1999-2004) of the National Health and Nutrition Examination Survey (NHANES) data. Levels of ILSBPD were calculated and divided into four groups based on three cut-off values of 5, 10 and 15mmHg. Time-to-event curves were estimated with the use of the Kaplan-Meier method, and two multivariable Cox proportional hazards regression models were conducted to assess the hazard ratios (HRs) and 95% confidence intervals (CIs) of all-cause and cardiovascular mortality associated with ILSBPD. RESULTS: A total of 6 842 subjects were included, with the mean (SD) age of 59.5 (12.8) years. By December 31, 2019, 2 544 and 648 participants were identified all-cause and cardiovascular mortality respectively during a median follow-up of 16.6 years. Time-to-event analyses suggested that higher ILSBPD was associated with increased all-cause and cardiovascular mortality (logrank, p < 0.001). Every 5mmHg increment of ILSBPD brings about 5% and 7% increased risk of all-cause and cardiovascular mortality, and individuals with an ILSBPD ≥ 15mmHg were significantly associated with higher incidence of all-cause mortality (HR 1.43, 95%CI 1.18-1.52, p < 0.001) and cardiovascular mortality (HR 1.73, 95%CI 1.36-2.20, p < 0.001) when multiple confounding factors were adjusted. Subgroup and sensitivity analysis confirmed the relationship. CONCLUSIONS: Our findings suggest that the increment of ILSBPD was significantly associated with higher risk of all-cause and cardiovascular mortality in general population.


Assuntos
Doenças Cardiovasculares , Humanos , Pessoa de Meia-Idade , Pressão Sanguínea/fisiologia , Inquéritos Nutricionais , Doenças Cardiovasculares/epidemiologia , Perna (Membro) , Fatores de Risco
6.
Artigo em Inglês | MEDLINE | ID: mdl-38596204

RESUMO

Background: Chronic obstructive pulmonary disease (COPD) is closely associated with frailty, and prevention of acute exacerbations is important for disease management. Moreover, COPD patients with frailty experience a higher risk of acute exacerbations. However, the frailty instruments that can better predict acute exacerbations remain unclear. Purpose: (1) To explore the factors influencing frailty and acute exacerbations in stable COPD patients, and (2) quantify the ability of multidimensional frailty instruments to predict acute exacerbations within 1 year. Patients and methods: In this retrospective longitudinal study, stable COPD patients were recruited from the outpatient department of Sichuan Provincial People's Hospital from July 2022 to June 2023. COPD patients reviewed their frailty one year ago and their acute exacerbations within one year using face-to-face interviews with a self-developed frailty questionnaire. Frailty status was assessed using the Frailty Index (FI), frailty questionnaire (FRAIL), and Clinical Frailty Scale (CFS). One-way logistic regression was used to explore the factors influencing frailty and acute exacerbations. Multivariate logistic regression was used to establish a prediction model for acute exacerbations, and the accuracy of the three frailty instruments was compared by measuring the area under the receiver operating characteristic curve (AUC). Results: A total of 120 individuals were included. Frailty incidence estimates using FI, FRAIL, and CFS were 23.3%, 11.7%, and 15.8%, respectively. The three frailty instruments showed consistency in COPD assessments (P<0.05). After adjusting for covariates, frailty reflected by the FI and CFS score remained an independent risk factor for acute exacerbations. The CFS score was the best predictor of acute exacerbations (AUC, 0.764 (0.663-0.866); sensitivity, 57.9%; specificity, 80.0%). Moreover, the combination of CFS plus FRAIL scores was a better predictor of acute exacerbations (AUC, 0.792 (0.693-0.891); sensitivity, 86.3%; specificity, 60.0%). Conclusion: Multidimensional frailty assessments could improve the identification of COPD patients at high risk of acute exacerbations and facilitate targeted interventions to reduce acute exacerbations in these patients.


Assuntos
Fragilidade , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Estudos Longitudinais , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Estudos Retrospectivos , Fatores de Risco
7.
Molecules ; 29(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611772

RESUMO

Developing high-efficiency membrane materials for the rapid removal of organic dyes is crucial but remains a challenge. Polyoxometalates (POMs) clusters with anionic structures are promising candidates for the removal of cationic dyes via electrostatic interactions. However, their shortcomings, such as their solubility and inability to be mass-produced, hinder their application in water pollution treatment. Here, we propose a simple and green strategy utilizing the room temperature stirring method to mass produce nanoscale polyoxometalate-based metal-organic frameworks (POMOFs) with porous rhomboid-shaped dodecahedral and hexagonal prism structures. The products were labeled as POMOF1 (POMOF-PW12) and POMOF2 (POMOF-PMo12). Subsequently, a series of x wt% POMOF1/PAN (x = 0, 3, 5, and 10) nanofiber membranes (NFMs) were prepared using electrospinning technology, where polyacrylonitrile (PAN) acts as a "glue" molecule facilitating the bonding of POMOF1 nanoparticles. The as-prepared samples were comprehensively characterized and exhibited obvious water stability, as well as rapid selective adsorption filtration performance towards cationic dyes. The 5 wt% POMOF1/PAN NFM possessed the highest removal efficiency of 96.7% for RhB, 95.8% for MB, and 86.4% for CV dyes, which realized the selective separation over 95% of positively charged dyes from the mixed solution. The adsorption mechanism was explained using FT-IR, SEM, Zeta potential, and adsorption kinetics model, which proved that separation was determined via electrostatic interaction, hydrogen bonding, and π-π interactions. Moreover, the POMOF1/PAN membrane presented an outstanding recoverable and stable removal rate after four cycles. This study provides a new direction for the systematic design and manufacture of membrane separation materials with outstanding properties for contaminant removal.

8.
Opt Express ; 32(5): 7136-7146, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439402

RESUMO

The Kramers-Kronig (KK) receiver has attracted much attention in short-range optical interconnection because of its ability to recover the phase of the signal from the intensity information through KK algorithm. In high-speed KK systems, such as virtual-carrier (VC) assisted ones, an alternating current (AC) coupled photo-detector (PD) is preferred due to relaxing the requirements of analog-to-digital converter (ADC) and electronic amplifier by filtering direct current (DC) component. However, the loss of the DC component will cause the KK algorithm to break down, so it is necessary to accurately recover DC value in the digital domain with multiple-sweep. In this paper, we propose what we believe is a novel non-sweep DC component estimation scheme based on optimized digital carrier-to-signal power ratio (OD-CSPR) method, which can accurately estimate the DC component with only 3-4 iterations in the scenario of VC-assisted KK receiver optical transmission. The scheme utilizes the one-dimensional search optimization algorithm based on golden section search and parabolic interpolation without sweeping. The simulation and experimental results of the proposed non-sweep OD-CSPR method show that the DC component can be estimated accurately in a large CSPR range, and the system performance is close to that of the conventional DC-sweep method. Compared with the typical defined digital CSPR (DD-CSPR) based optimization method, the proposed one can realize optical signal-to-noise ratio (OSNR) gains of 0.9 dB in the back-to-back (B2B) and 0.7 dB under 80 km fiber transmission scenarios respectively with a total bit rate of 160Gb/s.

9.
Eur J Nutr ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38478042

RESUMO

BACKGROUND: While folic acid (FA) is widely used to treat elevated total homocysteine (tHcy), promoting vascular health by reducing vascular oxidative stress and modulating endothelial nitric oxide synthase, the optimal daily dose and individual variation by MTHFR C677T genotypes have not been well studied. Therefore, this study aimed to explore the efficacy of eight different FA dosages on tHcy lowering in the overall sample and by MTHFR C677T genotypes. METHODS: This multicentered, randomized, double-blind, controlled clinical trial included 2697 eligible hypertensive adults with elevated tHcy (≥ 10 mmol/L) and without history of stroke and cardiovascular disease. Participants were randomized into eight dose groups of FA combined with 10 mg enalapril maleate, taken daily for 8 weeks of treatment. RESULTS: The intent to treat analysis included 2163 participants. In the overall sample, increasing FA dosage led to steady tHcy reduction within the FA dosing range of 0-1.2 mg. However, a plateau in tHcy lowering was observed in FA dose range of 1.2-1.6 mg, indicating a ceiling effect. In contrast, FA doses were positively and linearly associated with serum folate levels without signs of plateau. Among MTHFR genotype subgroups, participants with the TT genotype showed greater efficacy of FA in tHcy lowering. CONCLUSIONS: This randomized trial lent further support to the efficacy of FA in lowering tHcy; more importantly, it provided critically needed evidence to inform optimal FA dosage. We found that the efficacy of FA in lowering tHcy reaches a plateau if the daily dosage exceeds 1.2 mg, and only has a small gain by increasing the dosage from 0.8 to 1.2 mg. GOV IDENTIFIER: NCT03472508 (Registration Date: March 21, 2018).

10.
Foods ; 13(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38472767

RESUMO

Food provided a material foundation for the development of human society and was an important cornerstone for ensuring national security. The Chinese government has always attached great importance to food security, which is not only related to economic development and social stability but also to national security and self-reliance. As the core region for grain production and the supply of staple food in China, the major grain-producing areas account for 78.25% of the total national grain output, truly earning the title of China's "granary". Considering the establishment of 13 major grain-producing regions across the country in 2004 as a quasi-natural experiment, the impact of policies in major grain-producing regions on ensuring national food security is examined using a difference-in-differences method based on inter-provincial panel data for 30 provinces across the country from 1997 to 2020, and the mechanisms of their effects are further analyzed. The findings show that (1) the main producing-areas policy has a significant driving effect on China's food security, with an average annual increase of 0.0351 units in the food-security index, and the impact is expanding year by year. (2) The policy of the main grain-producing provinces mainly plays a role in guaranteeing food security by expanding the scale of grain cultivation and the scale of family land management in the main grain-producing provinces, and the scale effect of grain cultivation has a more significant impact. Further adjusting and improving the policy of the main grain-producing areas and expanding the scale-driven effect of this policy are of great significance for transforming agricultural production methods and realizing a strong agricultural country.

11.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474906

RESUMO

This paper proposes a wind-speed-adaptive resonant piezoelectric energy harvester for offshore wind energy collection (A-PEH). The device incorporates a coil spring structure, which sets the maximum threshold of the output rotational frequency, allowing the A-PEH to maintain a stable output rotational frequency over a broader range of wind speeds. When the maximum output excitation frequency of the A-PEH falls within the sub-resonant range of the piezoelectric beam, the device becomes wind-speed-adaptive, enabling it to operate in a sub-resonant state over a wider range of wind speeds. Offshore winds exhibit an annual average speed exceeding 5.5 m/s with significant variability. Drawing from the characteristics of offshore winds, a prototype of the A-PEH was fabricated. The experimental findings reveal that in wind speed environments, the device has a startup wind speed of 4 m/s, and operates in a sub-resonant state when the wind speed exceeds 6 m/s. At this point, the A-PEH achieves a maximum open-circuit voltage of 40 V and an average power of 0.64 mW. The wind-speed-adaptive capability of the A-PEH enhances its ability to harness offshore wind energy, showcasing its potential applications in offshore wind environments.

12.
Am J Chin Med ; 52(2): 513-539, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533568

RESUMO

Aging can cause degenerative changes in multiple tissues and organs. Gastrointestinal diseases and dysfunctions are common in the elderly population. In this study, we investigated the effects of Astragalus membranaceus polysaccharide (APS) and Astragalus membranaceus ethanol extract (AEE) on age-related intestinal dysfunction and gut microbiota dysbiosis in naturally aging mice. The energy expenditure and physical activity of 23-month-old C57BL6/J mice were recorded using a metabolic cage system. Pathological changes in the intestine were evaluated using Alcian blue staining. The protein levels of leucine-rich repeats containing G protein-coupled receptor 5 (Lgr5) and Stat3 in the small intestine were determined using immunohistochemistry. The intestinal cell migration distance was assessed using bromodeoxyuridine (BrdU) immunofluorescence staining. The gene transcription levels of intestinal stem cell (ISC) markers and ISC-related signaling pathways were detected using quantitative real-time PCR (qRT-PCR). Microbiota analysis based on 16S rDNA was performed to evaluate the composition of the gut microbiota. APS and AEE improved a series of aging phenotypes in female but not in male aging mice. APS and AEE ameliorate intestinal dysfunction and histopathological changes in aging mice. APS had a more significant anti-aging effect than AEE, particularly on intestinal dysfunction. APS promotes ISC regeneration by activating the IL-22 signaling pathway. Cohousing (CH) experiments further confirmed that APS induced the IL-22 signaling pathway by increasing the abundance of Lactobacillus, thereby promoting the regeneration of ISCs. Our results show that APS may serve as a promising agent for improving age-related intestinal dysfunction.


Assuntos
Astragalus propinquus , 60552 , Idoso , Humanos , Camundongos , Masculino , Feminino , Animais , Lactente , Pré-Escolar , Astragalus propinquus/química , Intestinos , Transdução de Sinais , Intestino Delgado , Células-Tronco , Polissacarídeos/farmacologia , Envelhecimento , Regeneração
13.
Insect Mol Biol ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549231

RESUMO

REPAT (response to pathogen) is an immune-associated gene family that plays important roles in insect immune response to pathogens. Although nine REPAT genes have been identified in Spodoptera frugiperda (Lepidoptera: Noctuidae) currently, their functions and mechanisms in the immune response to pathogens still remain unclear. Therefore, SfREPAT38, a pathogen response gene (REPAT) of S. frugiperda, was characterised and its function was analysed. The results showed that SfREPAT38 contains a signal peptide and a transcription activator MBF2 (multi-protein bridging factor 2) domain. Quantitative real-time polymerase chain reaction analysis showed that SfREPAT38 was highly expressed in the sixth-instar larvae (L6) and was the highest in expression in the midgut of L6. We found that the expression of SfREPAT38 could be activated by challenge with four microbial pathogens (Bacillus thuringiensis, Metarhizium anisopliae, Spodoptera exigua nuclearpolyhedrosis and Escherichia coli), except 12 h after E. coli infection. Furthermore, the SfREPAT38 expression levels significantly decreased at 24, 48 and 72 h after SfREPAT38 dsRNA injection or feeding. Feeding with SfREPAT38 dsRNA significantly decreased the weight gain of S. frugiperda, and continuous feeding led to the death of S. frugiperda larvae from the fourth day. Moreover, SfREPAT38 dsRNA injection resulted in a significant decrease of weight gain on the fifth day. Silencing SfREPAT38 gene down-regulated the expression levels of immune genes belonging to the Toll pathway, including SPZ, Myd88, DIF, Cactus, Pell and Toll18W. After treatment with SfREPAT38 dsRNA, S. frugiperda became extremely sensitive to the B. thuringiensis infection, and the survival rate dramatically increased, with 100% mortality by the eighth day. The weight of S. frugiperda larvae was also significantly lower than that of the control groups from the second day onwards. In addition, the genes involved in the Toll signalling pathway and a few antibacterial peptide related genes were down-regulated after treatment. These results showed that SfREPAT38 is involved in the immune response of S. frugiperda larvae through mediating Toll signalling pathway.

14.
Micromachines (Basel) ; 15(3)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38542561

RESUMO

Triboelectric nanogenerators (TENGs) can effectively collect low-frequency, disordered mechanical energy and are therefore widely studied in the field of ocean energy collection. Most of the rotary TENGs studied so far tend to have insufficient rotation, resulting in slow charge transfer rates in low-frequency ocean environments. For this reason, in this paper, we propose a wind-wave synergistic triboelectric nanogenerator (WWS-TENG). It is different from the traditional rotary TENGs based on free-standing mode in that its power generation unit has two types of rotors, and the two rotors rotate in opposite directions under the action of wind energy and wave energy, respectively. This type of exercise can more effectively collect energy. The WWS-TENG has demonstrated excellent performance in sea wind and wave energy harvesting. In the simulated ocean environment, the peak power can reach 13.5 mW under simulated wind-wave superposition excitation; the output of the WWS-TENG increased by 49% compared to single-wave power generation. The WWS-TENG proposal provides a novel means of developing marine renewable energy, and it also demonstrates broad application potential in the field of the self-powered marine Internet of Things (IoT).

15.
Comput Methods Programs Biomed ; 248: 108110, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452685

RESUMO

BACKGROUND AND OBJECTIVE: High-resolution (HR) MR images provide rich structural detail to assist physicians in clinical diagnosis and treatment plan. However, it is arduous to acquire HR MRI due to equipment limitations, scanning time or patient comfort. Instead, HR MRI could be obtained through a number of computer assisted post-processing methods that have proven to be effective and reliable. This paper aims to develop a convolutional neural network (CNN) based super-resolution reconstruction framework for low-resolution (LR) T2w images. METHOD: In this paper, we propose a novel multi-modal HR MRI generation framework based on deep learning techniques. Specifically, we construct a CNN based on multi-resolution analysis to learn an end-to-end mapping between LR T2w and HR T2w, where HR T1w is fed into the network to offer detailed a priori information to help generate HR T2w. Furthermore, a low-frequency filtering module is introduced to filter out the interference from HR-T1w during high-frequency information extraction. Based on the idea of multi-resolution analysis, detailed features extracted from HR T1w and LR T2w are fused at two scales in the network and then HR T2w is reconstructed by upsampling and dense connectivity module. RESULTS: Extensive quantitative and qualitative evaluations demonstrate that the proposed method enhances the recovered HR T2w details and outperforms other state-of-the-art methods. In addition, the experimental results also suggest that our network has a lightweight structure and favorable generalization performance. CONCLUSION: The results show that the proposed method is capable of reconstructing HR T2w with higher accuracy. Meanwhile, the super-resolution reconstruction results on other dataset illustrate the excellent generalization ability of the method.


Assuntos
Armazenamento e Recuperação da Informação , Médicos , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador
16.
Atherosclerosis ; : 117509, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38523002

RESUMO

BACKGROUND AND AIMS: Uncertainty of the causality determinations for ambient ozone (O3) on cardiovascular events is heightened by the limited understanding of the mechanisms involved in humans. We aimed to examine the pro-atherothrombotic impacts of O3 exposure and to explore the potential mediating roles of dysfunctional neutrophils, focusing on neutrophil extracellular traps (NETs). METHODS: A longitudinal panel study of 152 healthy adults was conducted in the cool to cold months with relatively low levels of O3 between September 2019 and January 2020 in Beijing, China. Four repeated measurements of indicators reflecting atherothrombotic balance and NETs were performed for each participant. RESULTS: Daily average exposure levels of ambient O3 were 16.6 µg/m3 throughout the study period. Per interquartile range increase in average concentrations of O3 exposure at prior up to 7 days, we observed elevations of 200.1-276.3% in D-dimer, 27.2-36.8% in thrombin-antithrombin complex, 10.8-60.3% in plasminogen activator inhibitor 1, 13.9-21.8% in soluble P-selectin, 16.5-45.1% in matrix metalloproteinase-8, and 2.4-12.4% in lipoprotein-associated phospholipase A2. These pro-atherothrombotic changes were accompanied by endothelial activation, lung injury, and immune inflammation. O3 exposure was also positively associated with circulating NETs indicators, including citrullinated histone H3, neutrophil elastase, myeloperoxidase, and double-stranded DNA. Mediation analyses indicated that NETs could mediate O3-associated pro-atherothrombotic responses. The observational associations remained significant and robust after controlling for other pollutants, and were generally greater in participants with low levels of physical activity. CONCLUSIONS: Ambient O3 exposure was associated with significant increases in NETs and pro-atherothrombotic potential, even at exposure levels well below current air quality guidelines of the World Health Organization.

17.
IEEE Trans Biomed Eng ; PP2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38457328

RESUMO

OBJECTIVE: Minimally invasive ultrasound ablation transducers have been widely studied. However, conventional designs are limited by the single working frequency, restricting their conformal ablation ability (i.e. ablation size and shape controllability). METHODS: New multi-frequency ultrasonic transducer design method is proposed based on the asymmetric backing layer, which divides the transducer into non-backing-layer region (i.e. front-piezoelectric region) and backing-layer region (i.e. front-piezoelectric-backing region) with multiple local thickness mode resonant frequencies. Ablation zone can be controlled by exciting the local resonance within or between the regions, and its control flexibility is further enhanced by driven under a multi-frequency modulation signal. Experiments and calculations are combined for verifying the proposal. RESULTS: The fabricated transducer with a Y-direction asymmetric backing layer shows five resonances, with two in each region and one resonance excited in both regions. Spatial ultrasound emission is demonstrated by acoustic measurements. Tissue ablation experiments verified spatial ablation zone control, and frequency modulation driving method enables the spatial transition of ablation zone from one region to the other, generating different ablation sizes and shapes. Finally, patient-specific simulations verified the effectiveness of conformal ablation. CONCLUSION: The proposed transducer enables flexible control of ablation zone. SIGNIFICANCE: This study demonstrates a new method for conformal tumor ablation.

18.
Harmful Algae ; 133: 102586, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38485436

RESUMO

The red Noctiluca scintillans (RNS) blooms often break out near Pingtan Island, in the northern Taiwan Strait from April to June. It is essential to gain insights into their formation mechanism to predict and provide early warnings for these blooms. Previous studies and observations showed that RNS blooms are the most likely to occur when winds are weak and shifting in direction. To explore this phenomenon further, we employed a high-resolution coastal model to investigate the hydrodynamics influencing RNS blooms around Pingtan Island from April to June 2022. The model results revealed that seawater exhibited weak circulation but strong stratification during RNS blooms. Residence time were examined through numerical experiments by releasing passive neutrally buoyant particles in three bays of Pingtan Island. The results showed a significantly longer residence time during RNS blooms, indicating reduced flushing capabilities within the bays, which could give RNS a stable environment to multiply and aggregate. This hydrodynamic condition provided a favorable basis for RNS blooms breakout near Pingtan Island. The shifts and weakening of the prevailing northeast wind contributed substantially to weakening the flow field around Pingtan Island and played a crucial role in creating the hydrodynamics conducive to RNS blooms. Our study offers fresh insights into the mechanisms underpinning RNS blooms formation near Pingtan Island, providing a vital framework for forecasting RNS blooms in this region.


Assuntos
Dinoflagelados , Monitoramento Ambiental , Taiwan , Monitoramento Ambiental/métodos , Estações do Ano , Surtos de Doenças
19.
Heliyon ; 10(3): e24837, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38314266

RESUMO

Background: Systemic immune-inflammation index (SII) is a novel biomarker of growing interest in predicting stroke. The aim of this study was to investigate its predictive value and explore its effect modification on folic acid supplement for stroke primary prevention in a Chinese population with hypertension. Methods: A total of 10,013 participants from the China Stroke Primary Prevention Trial with available neutrophil, platelet and lymphocyte count were included, including 5,019 subjects in the enalapril group and 4,994 in the enalapril-folic acid group. SII was calculated as (platelet × neutrophil)/lymphocyte. The primary endpoint was first stroke. Cox proportional hazards models were used to evaluate the association between SII and first stroke. Results: A U-shape association between SII and first stroke risk was observed in enalapril group. Compared with the reference group (Quartile 2: 335.1 to <443.9 × 109 cell/L), the adjusted HRs were 1.68 (95 % CI: 1.06-2.66, P = 0.027) in Quartile 1 (<335.1 × 109 cell/L), 1.43 (95 % CI: 0.90-2.27, P = 0.126) in Quartile 3 (443.9 to <602.6 × 109 cell/L), and 1.61 (95 % CI: 1.03-2.51, P = 0.035) in Quartile 4 (≥602.6 × 109 cell/L). There was no significant association between SII and first stroke in the enalapril-folic acid group, with adjusted HR of 0.92 (95%CI: 0.54-1.56, P = 0.749) in Quartile 1(<334.7 × 109 cell/L), 1.36 (95%CI: 0.84-2.21, P = 0.208) in Quartile 3 (446.2 to <595.2 × 109 cell/L), and 1.41 (95%CI: 0.87-2.27, P = 0.163) in Quartile 4 (≥595.2 × 109 cell/L). A remarkable interaction between baseline SII and folic acid supplement for stroke prevention was observed, with particularly reduced risk by 44 % (HR: 0.56; 95 % CI: 0.34-0.90; P = 0.018) in the lowest SII group (P for interaction = 0.041). Conclusions: Among Chinese adults with hypertension, both low and high SII at baseline predicted increased first stroke risk. And compensatory folic acid particularly reduced first stroke risk in the lowest SII subgroup.

20.
Analyst ; 149(7): 2023-2033, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38404152

RESUMO

A reduced graphene oxide/molybdenum selenosulfide (rGO/MoSSe) heterojunction was synthesized, and a molecularly imprinted photoelectrochemical sensor for the detection of chlortetracycline was prepared. MoSSe was grown in situ on rGO by a hydrothermal method to form an rGO/MoSSe heterojunction, which acts as the sensitive film of the sensor. Since rGO can promote electron transfer and effectively inhibit electron-hole recombination, it effectively reduces the recombination probability of electrons and holes and improves the photoelectric efficiency, thus enhancing the detection sensitivity of the PEC sensor. The rGO/MoSSe was immobilized on an FTO electrode, and molecularly imprinted polymers (MIPs) were prepared by electropolymerization on the rGO/MoSSe-modified FTO electrode with chlortetracycline as the template molecule and o-phenylenediamine as the functional monomer, so as to construct a molecularly imprinted photoelectrochemical (MIP-PEC) sensor. The determination of chlortetracycline was realized by the strategy of a "gate-controlled effect", and the detection range of the chlortetracycline concentration was 5.0 × 10-13-5 × 10-9 mol L-1 with a detection limit of 1.57 × 10-13 mol L-1. The sensor has been applied to the determination of chlortetracycline in animal-derived food samples.


Assuntos
Clortetraciclina , Grafite , Impressão Molecular , Animais , Molibdênio , Polímeros/química , Limite de Detecção , Eletrodos , Impressão Molecular/métodos , Técnicas Eletroquímicas/métodos
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