Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Asian Nat Prod Res ; : 1-20, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780602

RESUMO

In the current study, bioinformatics analysis of the hepatocellular carcinoma (HCC) dataset was conducted with the hepatoprotective effect of the Fuzheng Huayu (FZHY) capsule against the diethylnitrosamine-induced HCC progression analyzed. Eight cell clusters were defined and tanshinone IIA, arachidonic acid, and quercetin, compounds of the FZHY capsule, inhibit HCC progression-related fibrosis by regulating the expression of PLAU and IGFBP3. Combined with the ameliorative effect of the FZHY capsule against liver dysfunctions and expression of PLAU and IGFBP3, our study confirmed the effect of the FZHY capsule on inhibiting the fibrosis-associated HCC progression via regulating the expression of PLAU and IGFBP3.

2.
Opt Express ; 29(8): 11591-11604, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984936

RESUMO

Nonlinear Fourier transform, as a technique that has a great potential to overcome the capacity limit in fibre optical communication system, faces speed and accuracy bottlenecks in practice. Machine learning using convolutional neural networks shows great potential in NFT-based applications. We have developed a convolutional neural network for decoding information in NFT-based communication and numerically demonstrated its performance in comparison to a fast NFT algorithm. The comparison indicates the potential of conventional neural network to replace NFT calculations for decoding of information.

3.
Environ Sci Technol ; 55(18): 12261-12271, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34469681

RESUMO

Formation pathways and sources of atmosphere nitrate (NO3-) have attracted much attention as NO3- had detrimental effects on Earth's ecosystem and climate change. Here, we measured nitrogen (δ15N-NO3-) and oxygen (δ18O-NO3- and Δ17O-NO3-) isotope compositions in nitrate aerosols at the Qomolangma station (QOMS) over the Himalayan-Tibetan Plateau (HTP) to quantify the formation mechanisms and emission sources of nitrate at the background site. At QOMS, the enhanced NO3- concentrations were observed in the springtime. The average δ15N-NO3-, δ18O-NO3-, and Δ17O-NO3- values were 0.4 ± 4.9, 64.7 ± 11.5 and 27.6 ± 6.9‰, respectively. Seasonal variations of isotope ratios at QOMS can be explained by the different emissions and formation pathways to nitrate. The average fractions of NO2 + OH and N2O5 + H2O to nitrate production were estimated to be 43 and 52%, respectively, when the NO3 + hydrocarbon (HC)/dimethyl sulfide (DMS) (NO3 + HC/DMS) pathway was assumed to be 5%. Using stable isotope analysis in the R (SIAR) model, the relative contributions of biomass burning (BB), biogenic soil emission, traffic, and coal combustion to nitrate were estimated to be 28, 25, 24, and 23%, respectively, on yearly basis. By FLEXible PARTicle (FLEXPART) dispersion model, we highlighted that NOx from BB emission over South Asia that had undergone N2O5 + H2O processes enhanced the nitrate concentrations in the springtime over the HTP region.


Assuntos
Nitratos , Nitrogênio , Aerossóis , China , Ecossistema , Monitoramento Ambiental , Nitratos/análise , Nitrogênio/análise , Isótopos de Nitrogênio/análise , Isótopos de Oxigênio/análise , Tibet
4.
Neoplasma ; 68(5): 917-923, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33847131

RESUMO

Protein phosphatase 1H (PPM1H) is the metal-dependent protein phosphatase, however, its role in tumorigenesis and tumor progression remains controversial. Non-small-cell lung cancer (NSCLC) is the most common histological type of lung cancer but the expression and clinical significance of PPM1H in NSCLC is unknown. In our study, we detected the mRNA of PPM1H in 25 pairs of NSCLC tissues and their corresponding adjacent tissues with qRT-PCR. Moreover, we investigated PPM1H expression in 474 NSCLC tissues and divided them into subgroups with low and high PPM1H. We further evaluated its correlation with the clinicopathological factors. The correlation between PPM1H and other biomarkers involved in tumor progression including chromosome segregation 1-like protein (CSE1L), p53, and Ki67 was also estimated. In addition, the prognostic significance of PPM1H was investigated by univariate and multivariate analyses. The mRNA levels of PPM1H in NSCLCs were significantly higher than those in tumor-adjacent tissues. Patients with low and high PPM1H expression accounted for 54.64% (259/474) and 45.36% (215/474) respectively in all the NSCLCs. PPM1H expression (p=0.012), patients' sex (p=0.009), tumor size (p<0.001), histological grade (p=0.026), T stage (p=0.002), N stage (p<0.001), M stage (p=0.011), and TNM stage (p<0.001) were all associated with the poor prognosis. With multivariate analysis, PPM1H was determined as an independent prognostic factor of NSCLC (HR=1.42, 95% CI=1.14-1.75, p=0.001). Moreover, high PPM1H was significantly with high Ki67 (p=0.022), indicating the oncogenic role of PPM1H. PPM1H is an independent prognostic factor indicating an unfavorable prognosis of NSCLC. Our results indicated that PPM1H was an important supplement of NSCLC molecular profile and detecting PPM1H may help recognize the high-risk patients for further treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Fosfoproteínas Fosfatases , Prognóstico
5.
Anal Chem ; 92(21): 14373-14382, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33047954

RESUMO

Carbon content constitutes a major fraction of atmospheric particulate matter (PM) and directly influences the earth's climate and human health. The stable carbon isotope ratios (δ13C) can be used to track potential sources and atmospheric processes of carbonaceous aerosols. Previously, determination of δ13C was always conducted in offline carbonaceous aerosol samples. The poor time-resolution results cannot provide information regarding the temporal evolution of δ13C at a short-time scale. In this study, we developed a new system for online measurements of δ13C in atmospheric carbonaceous aerosols by combining a semicontinuous organic carbon/elemental carbon (OC/EC) analyzer and online cavity ring-down spectroscopy (CRDS) (OC/EC analyzer-CRDS). To provide better stability in the determination of δ13C, a carrier gas with CO2 (∼200 ppm) in "balance gas" was used, and Keeling analysis was employed to separate the δ13C signal of the sample from background CO2 gas. Our results showed that the accuracy and absolute precision of the δ13C measurements by the OC/EC analyzer-CRDS system were better than 0.1‰ and 0.5‰, respectively, for the samples containing carbon content more than 5 µg. Furthermore, we employed this system to monitor δ13C (δ13C-TC) in particulate total carbon (TC) with a time resolution of 2-4 h over Beijing in late summer and early autumn, 2019. During the sampling period, the TC concentrations varied from 0.1 to 12.0 µg m-3 with a mean value of 6.0 ± 2.4 µg m-3. The δ13C-TC ranged from -28.2 to -24.2‰ (mean value was -25.9 ± 0.9‰) without significant diurnal variations, suggesting similar contributing sources to TC. Comparing the δ13C signatures of different emissions, we found that liquid fuels and primary and secondary C3 plants were likely the dominant sources of particulate TC. Finally, we found that atmospheric heavy precipitation washed out the aged aerosols from the polluted air, resulting in significant depletion (∼2.4‰) of δ13C-TC in the atmosphere. This paper described a novel system for conducting online measurements of δ13C in atmospheric carbonaceous aerosols and provided us information to better understand the temporal evolution of emission sources and atmospheric processes of carbonaceous aerosols.


Assuntos
Atmosfera/química , Isótopos de Carbono/análise , Isótopos de Carbono/química , Análise Espectral/métodos , Aerossóis
6.
J Clin Lab Anal ; 34(7): e23293, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32157741

RESUMO

BACKGROUND: Atherosclerosis is the most frequent pathological process that causes cardiovascular diseases. OBJECTIVE: The present study aimed to confirm miRNAs associated with atherosclerosis and explore the molecular mechanism of miR-34c and its target high mobility group box protein 1 (HMGB1) in the control of growth of smooth muscle cells in the development of atherosclerosis. METHODS: Real-time PCR was firstly performed to confirm miRNA correlation with atherosclerosis, and computational analysis and luciferase assay were performed to explore the target of miR-34c, Western blot, and real-time PCR were also utilized to reveal the effect of whether high glucose (HG) and miR-34c affect miR-34c, HMGB1 levels, NF-κB p65 and TNF-α levels, and the role of miR-34c on vascular smooth muscle cells (VSMCs) viability induced by HG. Students' unpaired t test was performed to compare data between two groups. RESULTS: MiR-34c level was associated with atherosclerosis with different expression between VSMCs treated with high glucose or normal VSMCs. Then, HMGB1 is a virtual target of miR-34c with predicted binding site resided in HMGB1 3'UTR and further verified by that miR-34c remarkably reduced luciferase activity of wild HMGB1 3'UTR under a concentration-dependent fashion, and miR-34c cannot influence luciferase activity of mutant HMGB1 3'UTR. CONCLUSIONS: The results suggested miR-34c might be a novel therapeutic strategy in the management of atherosclerosis by suppressing the expression of HGMB1 and its downstream effectors.


Assuntos
Proteína HMGB1/genética , MicroRNAs/genética , Músculo Liso Vascular/citologia , Regiões 3' não Traduzidas , Proliferação de Células/genética , Sobrevivência Celular , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Glucose/farmacologia , Proteína HMGB1/metabolismo , Humanos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/efeitos dos fármacos , NF-kappa B/genética , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
Mol Plant Microbe Interact ; 31(2): 260-273, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29068240

RESUMO

Cutinases have been implicated as important enzymes during the process of fungal infection of aerial plant organs. The function of cutinases in the disease cycle of fungal pathogens that invade plants through the roots has been less studied. Here, functional analysis of 13 cutinase (carbohydrate esterase family 5 domain-containing) genes (VdCUTs) in the highly virulent vascular wilt pathogen Verticillium dahliae Vd991 was performed. Significant sequence divergence in cutinase family members was observed in the genome of V. dahliae Vd991. Functional analyses demonstrated that only VdCUT11, as purified protein, induced cell death and triggered defense responses in Nicotiana benthamiana, cotton, and tomato plants. Virus-induced gene silencing showed that VdCUT11 induces plant defense responses in Nicotiana benthamania in a BAK1 and SOBIR-dependent manner. Furthermore, coinfiltration assays revealed that the carbohydrate-binding module family 1 protein (VdCBM1) suppressed VdCUT11-induced cell death and other defense responses in N. benthamiana. Targeted deletion of VdCUT11 in V. dahliae significantly compromised virulence on cotton plants. The cutinase VdCUT11 is an important secreted enzyme and virulence factor that elicits plant defense responses in the absence of VdCBM1.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Gossypium/imunologia , Gossypium/microbiologia , Verticillium/enzimologia , Sequência de Aminoácidos , Regulação Fúngica da Expressão Gênica , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Nicotiana , Verticillium/metabolismo , Verticillium/patogenicidade , Virulência
8.
New Phytol ; 217(2): 756-770, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29084346

RESUMO

Verticillium dahliae isolates are most virulent on the host from which they were originally isolated. Mechanisms underlying these dominant host adaptations are currently unknown. We sequenced the genome of V. dahliae Vd991, which is highly virulent on its original host, cotton, and performed comparisons with the reference genomes of JR2 (from tomato) and VdLs.17 (from lettuce). Pathogenicity-related factor prediction, orthology and multigene family classification, transcriptome analyses, phylogenetic analyses, and pathogenicity experiments were performed. The Vd991 genome harbored several exclusive, lineage-specific (LS) genes within LS regions (LSRs). Deletion mutants of the seven genes within one LSR (G-LSR2) in Vd991 were less virulent only on cotton. Integration of G-LSR2 genes individually into JR2 and VdLs.17 resulted in significantly enhanced virulence on cotton but did not affect virulence on tomato or lettuce. Transcription levels of the seven LS genes in Vd991 were higher during the early stages of cotton infection, as compared with other hosts. Phylogenetic analyses suggested that G-LSR2 was acquired from Fusarium oxysporum f. sp. vasinfectum through horizontal gene transfer. Our results provide evidence that horizontal gene transfer from Fusarium to Vd991 contributed significantly to its adaptation to cotton and may represent a significant mechanism in the evolution of an asexual plant pathogen.


Assuntos
Fusarium/genética , Transferência Genética Horizontal , Genoma Fúngico , Genômica , Gossypium/microbiologia , Verticillium/genética , Verticillium/patogenicidade , Fatores de Virulência/metabolismo , Sequência de Bases , Evolução Molecular , Interações Hospedeiro-Patógeno/genética , Lactuca/microbiologia , Solanum lycopersicum/microbiologia , Família Multigênica , Filogenia , Especificidade da Espécie , Sintenia/genética , Virulência/genética
9.
Environ Microbiol ; 19(5): 1914-1932, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28205292

RESUMO

Glycoside hydrolase 12 (GH12) proteins act as virulence factors and pathogen-associated molecular patterns (PAMPs) in oomycetes. However, the pathogenic mechanisms of fungal GH12 proteins have not been characterized. In this study, we demonstrated that two of the six GH12 proteins produced by the fungus Verticillium dahliae Vd991, VdEG1 and VdEG3 acted as PAMPs to trigger cell death and PAMP-triggered immunity (PTI) independent of their enzymatic activity in Nicotiana benthamiana. A 63-amino-acid peptide of VdEG3 was sufficient for cell death-inducing activity, but this was not the case for the corresponding peptide of VdEG1. Further study indicated that VdEG1 and VdEG3 trigger PTI in different ways: BAK1 is required for VdEG1- and VdEG3-triggered immunity, while SOBIR1 is specifically required for VdEG1-triggered immunity in N. benthamiana. Unlike oomycetes, which employ RXLR effectors to suppress host immunity, a carbohydrate-binding module family 1 (CBM1) protein domain suppressed GH12 protein-induced cell death. Furthermore, during infection of N. benthamiana and cotton, VdEG1 and VdEG3 acted as PAMPs and virulence factors, respectively indicative of host-dependent molecular functions. These results suggest that VdEG1 and VdEG3 associate differently with BAK1 and SOBIR1 receptor-like kinases to trigger immunity in N. benthamiana, and together with CBM1-containing proteins manipulate plant immunity.


Assuntos
Glicosídeo Hidrolases/metabolismo , Gossypium/microbiologia , Nicotiana/microbiologia , Imunidade Vegetal/fisiologia , Receptores de Superfície Celular/metabolismo , Verticillium/patogenicidade , Morte Celular , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Verticillium/metabolismo , Fatores de Virulência/metabolismo
10.
Opt Express ; 24(8): 8832-47, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27137317

RESUMO

This paper examines the opportunities existing for engineering dispersion in non-silica whispering gallery mode microbubble resonators, for applications such as optical frequency comb generation. More specifically, the zero dispersion wavelength is analyzed as a function of microbubble diameter and wall thickness for several different material groups such as highly-nonlinear soft glasses, polymers and crystalline materials. The zero dispersion wavelength is shown to be highly-tunable by changing the thickness of the shell. Using certain materials it is shown that dispersion equalization can be realized at interesting wavelengths such as deep within the visible or mid-infrared, opening up new possibilities for optical frequency comb generation. This study represents the first extensive analysis of the prospects of using non-silica microbubbles for nonlinear optics.

11.
Opt Express ; 24(24): 27177-27183, 2016 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-27906292

RESUMO

We report mode-locked ~1550 nm output of transform-limited ~180 fs pulses from a large mode-area (diameter ~50 µm) guided-wave erbium fluorozirconate glass laser. The passively mode-locked oscillator generates pulses with 25 nm bandwidth at 156 MHz repetition rate and peak-power of 260 W. Scalability to higher repetition rate is demonstrated by transform-limited 410 fs pulse output at 1.3 GHz. To understand the origins of the broad spectral output, the laser cavity is simulated by using a numerical solution to the Ginzburg-Landau equation. This paper reports the widest bandwidth and shortest pulses achieved from an ultra-fast laser inscribed waveguide laser.

12.
Opt Lett ; 41(6): 1257-60, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26977683

RESUMO

We explore the scope for engineering dispersion in whispering gallery mode silica microbubbles for nonlinear applications, such as optical frequency comb generation. In particular, the zero dispersion wavelength is shown to be highly tunable by changing the thickness of the shell. Using a small diameter and small wall thickness, dispersion equalization within the visible is predicted. This opens up the possibility of realizing visible frequency combs for a range of different applications.


Assuntos
Microbolhas , Fenômenos Ópticos , Dióxido de Silício , Absorção de Radiação
13.
Med Sci Monit ; 22: 4066-4072, 2016 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-27794186

RESUMO

BACKGROUND The objective of this study was to investigate the molecular mechanism by which miR-637 interferes with the expression of CDK6, which contributes to the development of pulmonary hypertension (PH) with chronic obstructive pulmonary disease (COPD). MATERIAL AND METHODS We used an online miRNA database to identify CDK6 as a virtual target of miR-637, and validated the hypothesis using luciferase assay. Furthermore, we transfected SMCs with miR-637 mimics and inhibitor, and expression of CDK6 was determined using Western blot and real-time PCR. RESULTS In this study, we identified CDK6 as a target of miR-637 in smooth muscle cells (SMCs), and determined the expression of miR-637 in SMCs from PH patients with COPD and normal controls. We also identified the exact miR-637 binding site in the 3'UTR of CDK6 by using a luciferase reporter system. The mRNA and protein expression levels of CDK6 in SMCs from PH patients with COPD were clearly upregulated compared with the normal controls. Cells exposed to hypoxia also showed notably increased CKD6 mRNA and protein expression levels, and when treated with miR-637 or CDK6 siRNA, this increase in CKD6 expression was clearly attenuated. Additionally, cell viability and cell cycle analysis showed that hypoxia markedly increased viability of SMCs by causing an accumulation in S phase, which was relieved by the introduction of miR-637 or CDK6 siRNA. CONCLUSIONS Our study proved that the CDK6 gene is a target of miR-637, and demonstrated the regulatory association between miR-637 and CDK6, suggesting a possible therapeutic target for PH, especially in patients with COPD.


Assuntos
Quinase 6 Dependente de Ciclina/biossíntese , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Regiões 3' não Traduzidas , Estudos de Casos e Controles , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Quinase 6 Dependente de Ciclina/genética , Regulação para Baixo , Humanos , Hipertensão Pulmonar/enzimologia , Hipóxia/enzimologia , Hipóxia/genética , Hipóxia/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Cultura Primária de Células , RNA Mensageiro/metabolismo , RNA Interferente Pequeno
14.
Opt Express ; 22(22): 27643-54, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25401908

RESUMO

We numerically investigate nonlinear self-polarization flipping in a silicon waveguide. We identify specific silicon waveguide geometries that enhance this effect to facilitate its fabrication and experimental demonstration by varying various parameters such as fabrication distortion, waveguide loss, dispersion and laser noise to design the silicon waveguide. In optimized waveguides, we show that nonlinear self-polarization flipping can be observed with few tens of watts peak power pulses with widths as short as 60 ps and laser noise level as large as 7%.

15.
ACS Biomater Sci Eng ; 10(6): 4046-4058, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38722544

RESUMO

Cadmium poses a severe health risk, impacting various bodily systems. Monitoring human exposure is vital. Urine and blood cadmium serve as critical biomarkers. However, current urine and blood cadmium detection methods are expensive and complex. Being cost-effective, user-friendly, and efficient, visual biosensing offers a promising complement to existing techniques. Therefore, we constructed a cadmium whole-cell biosensor using CadR10 and deoxyviolacein pigment in this study. We assessed the sensor for time-dose response, specific response to cadmium, sensitivity response to cadmium, and stability response to cadmium. The results showed that (1) the sensor had a preferred signal-to-noise ratio when the incubation time was 4 h; (2) the sensor showed excellent specificity for cadmium compared to the group 12 metals and lead; (3) the sensor was responsive to cadmium down to 1.53 nM under experimental conditions and had good linearity over a wide range from 1.53 nM to 100 µM with good linearity (R2 = 0.979); and (4) the sensor had good stability. Based on the excellent results of the performance tests, we developed a cost-effective, high-throughput method for detecting urinary and blood cadmium. Specifically, this was realized by adding the blood or urine samples into the culture system in a particular proportion. Then, the whole-cell biosensor was subjected to culture, n-butanol extraction, and microplate reading. The results showed that (1) at 20% urine addition ratio, the sensor had an excellent curvilinear relationship (R2 = 0.986) in the range of 3.05 nM to 100 µM, and the detection limit could reach 3.05 nM. (2) At a 10% blood addition ratio, the sensor had an excellent nonlinear relationship (R2 = 0.978) in the range of 0.097-50 µM, and the detection limit reached 0.195 µM. Overall, we developed a sensitive and wide-range method based on a whole-cell biosensor for the detection of cadmium in blood and urine, which has the advantages of being cost-effective, ease of operation, fast response, and low dependence on instrumentation and has the potential to be applied in the monitoring of cadmium exposure in humans as a complementary to the mainstream detection techniques.


Assuntos
Técnicas Biossensoriais , Cádmio , Humanos , Cádmio/urina , Cádmio/sangue , Cádmio/análise , Técnicas Biossensoriais/métodos , Limite de Detecção
16.
Biosens Bioelectron ; 248: 115961, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38150800

RESUMO

Whole-cell biosensors could be helpful for in situ disease diagnosis. However, their use in analyzing biological samples has been hindered by unstable responses, low signal enhancement, and growth inhibition in complex media. Here, we offered a solution by building a visual whole-cell biosensor for urinary mercury determination. With deoxyviolacein as the preferred signal for the mercury biosensor for the first time, it enabled the quantitative detection of urinary mercury with a favorable linear range from 1.57 to 100 nM. The biosensor can accurately diagnose urine mercury levels exceeding the biological exposure index with 95.8% accuracy. Thus, our study provided a biosensing platform with great potential to serve as a stable, user-friendly, and high-throughput alternative for the daily monitoring or estimating of urinary mercury.


Assuntos
Técnicas Biossensoriais , Mercúrio , Humanos , Ensaios de Triagem em Larga Escala
17.
Opt Express ; 21(25): 31309-17, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-24514705

RESUMO

We report progress towards the realization of optical modulators based on electro-optic effects in soft glass fibres. A hybrid fabrication procedure was developed for producing microstructured lead silicate glass fibres with internal electrodes. Electro-optical characterization confirms experimentally that the enhanced nonlinear properties and superior isolation between the optical field and the electrodes make these fibres an ideal candidate platform for efficient electro-optical devices.


Assuntos
Eletrodos , Eletrônica/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Chumbo/química , Silicatos/química , Desenho de Equipamento , Análise de Falha de Equipamento
18.
Huan Jing Ke Xue ; 44(12): 6486-6494, 2023 Dec 08.
Artigo em Zh | MEDLINE | ID: mdl-38098377

RESUMO

As the main pollutants of secondary inorganic aerosols(SIAs) in fine particulate matter(PM2.5), aerosol ammonium(p-NH4+) plays a significant role in the formation of haze. However, the contribution ratio of each potential source of atmospheric NHx(p-NH4+ and NH3) still remains controversial. In this study, 3 h high-frequency PM2.5 samples were collected in Dongshan, Suzhou during winter and summer in 2015, respectively. Meanwhile, we determined concentrations and δ15N isotope ratios of total nitrogen(TN) and p-NH4+ and quantitatively analyzed formation processes and sources of p-NH4+ based on the Bayesian mixing model(SIAR). SO42-, NO3-, and NH4+ were the main water-soluble ions(WSIs) both in winter and summer, accounting for more than 70% in general. The concentration change trends of PM2.5, TN, and p-NH4+ were consistent, and the concentrations in winter were 2-3 times those in summer. The δ15N-NH4+ value was in direct proportion to the p-NH4+ concentration both in winter and summer. However, δ15N-NH4+ values in winter(-1.7‰±4.3‰) were lower than those in summer(7.8‰±5.9‰). This indicated that the differences in δ15N-NH4+ were caused by different contribution rates of each potential source within each season, whereas it was mainly led by nitrogen isotope fractionation during ammonium-ammonia gas particle distribution in different seasons. The SIAR model calculated that non-agricultural sources were the dominant source of p-NH4+ in Dongshan, with the contribution rate of 59% in winter and 69% in summer, which indicated that NH3 emitted by fossil fuel combustion more easily formed particle aerosol ammonium than that volatilized from agricultural sources.

19.
Biosensors (Basel) ; 13(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37998124

RESUMO

Dysregulated production of hydrogen sulphide in the human body has been associated with various diseases including cancer, underlining the importance of accurate detection of this molecule. Here, we report the detection of hydrogen sulphide using fluorescence-emission enhancement of two 1,8-naphthalimide fluorescent probes with an azide moiety in position 4. One probe, serving as a control, featured a methoxyethyl moiety through the imide to evaluate its effectiveness for hydrogen sulphide detection, while the other probe was modified with (3-aminopropyl)triethoxysilane (APTES) to enable direct covalent attachment to an optical fibre tip. We coated the optical fibre tip relatively homogeneously with the APTES-azide fluorophore, as confirmed via x-ray photoelectron spectroscopy (XPS). The absorption and fluorescence responses of the control fluorophore free in PBS were analysed using UV-Vis and fluorescence spectrophotometry, while the fluorescence emission of the APTES-azide fluorophore-coated optical fibres was examined using a simple, low-cost optical fibre-based setup. Both fluorescent probes exhibited a significant increase (more than double the initial value) in fluorescence emission upon the addition of HS- when excited with 405 nm. However, the fluorescence enhancement of the coated optical fibres demonstrated a much faster response time of 2 min (time for the fluorescence intensity to reach 90% of its maximum value) compared to the control fluorophore in solution (30 min). Additionally, the temporal evolution of fluorescence intensity of the fluorophore coated on the optical fibre was studied at two pH values (7.4 and 6.4), demonstrating a reasonable overlap and confirming the compound pH insensitivity within this range. The promising results from this study indicate the potential for developing an optical fibre-based sensing system for HS- detection using the synthesised fluorophore, which could have significant applications in health monitoring and disease detection.


Assuntos
Sulfeto de Hidrogênio , Humanos , Fibras Ópticas , Corantes Fluorescentes/química , Azidas , Espectrometria de Fluorescência
20.
J Geriatr Cardiol ; 20(4): 256-267, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37122993

RESUMO

OBJECTIVE: To evaluate the feasibility and tolerability of metoprolol standard dosing pathway (MSDP) in Chinese patients with acute coronary syndrome (ACS). METHODS: In this multicenter, prospective, open label, single-arm and interventional study that was conducted from February 2018 to April 2019 in fifteen Chinese hospitals. A total of 998 hospitalized patients aged ≥ 18 years and diagnosed with ACS were included. The MSDP was applied to all eligible ACS patients based on the standard treatment recommended by international guidelines. The primary endpoint was the percentage of patients achieving the target dose at discharge (V2). The secondary endpoints included the heart rate and blood pressure at V2 and four weeks after discharge (V4), and percentage of patients experiencing bradycardia (heart rate < 50 beats/min), hypotension (blood pressure < 90/60 mmHg) and transient cardiac dysfunction at V2 and V4. RESULTS: Of the 998 patients, 29.46% of patients achieved the target dose (≥ 95 mg/d) at V2. The total population was divided into two groups: target group (patients achieving the target dose at V2) and non-target group (patients not achieving the target dose at V2). There was significant difference in the reduction of heart rate from baseline to discharge in the two groups (-4.97 ± 11.90 beats/min vs. -2.70 ± 9.47 beats/min, P = 0.034). There was no significant difference in the proportion of bradycardia that occurred in the two groups at V2 (0 vs. 0, P = 1.000) and V4 (0.81% vs. 0.33%, P = 0.715). There was no significant difference in the proportion of hypotension between the two groups at V2 (0.004% vs. 0.004%, P = 1.000) and V4 (0 vs. 0.005%, P = 0.560). No transient cardiac dysfunction occurred in two groups during the study. A total of five adverse events (1.70%) and one serious adverse event (0.34%) were related to the pathway in target group. CONCLUSIONS: In Chinese ACS patients, the feasibility and tolerability of the MSDP have been proved to be acceptable.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA