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1.
Ecotoxicol Environ Saf ; 190: 110148, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31911388

RESUMO

Phthalate esters have raised public concerns owing to their effects on the environment and human health. We identified a novel phthalate-degrading hydrolase, EstJ6, from a metagenomic library using function-driven screening. Phylogenetic analysis indicated that EstJ6 is a member of family IV esterases. EstJ6 hydrolyzed various dialkyl and monoalkyl phthalate esters, and exhibited high hydrolytic activity (128 U/mg) toward dibutyl phthalate at 40 °C and pH 7.5. EstJ6 hydrolyzed not only common phthalate esters with simple side chains but also diethylhexyl phthalate and monoethylhexyl phthalate, which have complex and long side chains. Site-directed mutagenesis indicated that the catalytic triad residues of EstJ6 consists of Ser146, Glu240, and His270. EstJ6 is therefore a promising biodegradation enzyme, and our study illustrates the advantages of a metagenomic approach in identifying enzyme-coding genes for agricultural, food, and biotechnological applications.

2.
Environ Int ; 126: 228-233, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30822651

RESUMO

Human-induced climate change has accelerated in recent decades, causing adverse health effects. However, the impact of the changing climate on neurological disorders in the older population is not well understood. We applied time-varying Cox proportional hazards models to estimate the associations between hospital admissions for dementia and the mean and variability of summer and winter temperatures in New England. We estimated seasonal temperatures for each New England zip code using a satellite-based prediction model. By characterizing spatial differences and temporal fluctuations in seasonal temperatures, we observed a lower risk of dementia-associated hospital admissions in years when local temperatures in either summer (hazard ration [HR] = 0.98; 95% confidence interval [CI]: 0.96, 1.00) or winter (HR = 0.97; 95% CI: 0.94, 0.99) were higher than average, and a greater risk of dementia-associated admissions for older adults living in zip codes with higher temperature variations. Effect modifications by sex, race, age, and dual eligibility were considered to examine vulnerability of population subgroups. Our results suggest that cooler-than-average temperatures and higher temperature variability increase the risk of dementia-associated hospital admissions. Thus, climate change may affect progression of dementia and associated hospitalization costs.


Assuntos
Mudança Climática , Demência/epidemiologia , Hospitalização/estatística & dados numéricos , Temperatura Ambiente , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , New England/epidemiologia , Estações do Ano
3.
J Cancer Res Ther ; 14(4): 860-863, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29970666

RESUMO

Objective: This study was aimed to explore the expression level of long noncoding RNA H19 in the plasma of patients with nonsmall cell lung cancer (NSCLC) and its clinical significance. Methods: A total of 66 NSCLC patients (case group) and 31 patients with benign lung disease (control group) admitted from February 2015 to February 2017 were included in this study. Real-time polymerase chain reaction assay was applied to examine the relative expression level of long noncoding RNA H19 in the plasma of the two groups. The relationship between H19 expression and clinical, pathological features was explored. Receiver-operating characteristic (ROC) curve was applied to evaluate the clinical value of plasma H19 as a tumor marker in the auxiliary diagnosis of NSCLC. Results: The relative expression levels of plasma H19 inpatients from NSCLC group and benign lung disease group were 5.62 ± 2.02 (ΔCt) and 7.74 ± 2.75 (ΔCt), respectively. The NSCLC group presented with significantly higher levels than that of the benign disease group (P < 0.05). According to the median of relative expression level of 5.54, the plasma H19 of NSCLC patients was classified into low expression group ≥5.54 (n = 34) and high expression group <5.52 (n = 32). The relationship between the patients' clinical, pathological features, and the expression level of H19 was analyzed. The expression of H19 was not significantly correlated with the gender, age, clinical staging, tumor diameter, and pathological type of the patients (Pall > 0.05). With the serum H19 as a diagnosis reference, the diagnostic sensitivity of NSCLC was 67.74%, and the specificity was 63.08%. The area under the ROC curve was 0.73, and the diagnostic cutoff value was 6.62. Conclusion: Plasma level of H19 in NSCLC patients was significantly increased, which could be applied as a serological marker for the auxiliary diagnosis of NSCLC.


Assuntos
Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Ácidos Nucleicos Livres , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , Humanos , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Longo não Codificante/sangue , Curva ROC
4.
Appl Opt ; 56(32): 9098-9104, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29131199

RESUMO

In deterministic computer-controlled optical surfacing, accurate dwell time execution by computer numeric control machines is crucial in guaranteeing a high-convergence ratio for the optical surface error. It is necessary to consider the machine dynamics limitations in the numerical dwell time algorithms. In this paper, these constraints on dwell time distribution are analyzed, and a model of the equal extra material removal is established. A positive dwell time algorithm with minimum equal extra material removal is developed. Results of simulations based on deterministic magnetorheological finishing demonstrate the necessity of considering machine dynamics performance and illustrate the validity of the proposed algorithm. Indeed, the algorithm effectively facilitates the determinacy of sub-aperture optical surfacing processes.

5.
Opt Express ; 25(22): 26600-26614, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092149

RESUMO

Belt magnetorheological finishing (Belt-MRF) is a promising tool for large-optics processing. However, before using a spot, its shape should be designed and controlled by the polishing gap. Previous research revealed a remarkably nonlinear relationship between the removal function and normal pressure distribution. The pressure is nonlinearly related to the gap geometry, precluding prediction of the removal function given the polishing gap. Here, we used the concepts of gap slope and virtual ribbon to develop a model of removal profiles in Belt-MRF. Between the belt and the workpiece in the main polishing area, a gap which changes linearly along the flow direction was created using a flat-bottom magnet box. The pressure distribution and removal function were calculated. Simulations were consistent with experiments. Different removal functions, consistent with theoretical calculations, were obtained by adjusting the gap slope. This approach allows to predict removal functions in Belt-MRF.

6.
Appl Opt ; 55(22): 5814-20, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27505358

RESUMO

We develop a kind of magnetorheological (MR) polishing fluid for the fabrication of a silicon modification layer on a silicon carbide substrate based on chemical theory and actual polishing requirements. The effect of abrasive concentration in MR polishing fluid on material removal rate and removal function shape is investigated. We conclude that material removal rate will increase and tends to peak value as the abrasive concentration increases to 0.3 vol. %, and the removal function profile will become steep, which is a disadvantage to surface frequency error removal at the same time. The removal function stability is also studied and the results show that the prepared MR polishing fluid can satisfy actual fabrication requirements. An aspheric reflective mirror of silicon carbide modified by silicon is well polished by combining magnetorheological finishing (MRF) using two types of MR polishing fluid and computer controlled optical surfacing (CCOS) processes. The surface accuracy root mean square (RMS) is improved from 0.087λ(λ=632.8 nm) initially to 0.020λ(λ=632.8 nm) in 5.5 h total and the tool marks resulting from MRF are negligible. The PSD analysis results also shows that the final surface is uniformly polished.

7.
J Asthma ; 52(10): 981-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26300019

RESUMO

OBJECTIVE: There has been significant interest in the association between asthma and the polymorphisms of IL-17A and IL-17F for a period of time. This work aims to present a clearer relationship between asthma and the polymorphisms of IL-17A and IL-17F. METHOD: Searches were performed in Medline, EMBASE, and the Chinese National Knowledge Infrastructure (CNKI) databases. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the relationship between polymorphisms of IL-17A and IL-17F and asthma. RESULTS: Nine studies comprising 3650 asthmatics and 3370 controls were included in this meta-analysis for all single nucleotide polymorphisms (SNPs) (2-6 per SNP). Our study examined the polymorphisms of IL-17F rs1889570 (C/T) (CC versus TT: OR = 0.55, 95%CI = 0.41-0.75; CT versus TT: OR = 0.54, 95%CI = 0.40-0.72; CC/CT versus TT: OR = 0.55, 95%CI = 0.42-0.72; CC versus CT/TT, OR = 1.83, 95%CI = 1.39-2.41), IL-17A rs4711998(A/G) (AA/AG versus GG: OR = 0.67, 95%CI = 0.46-0.98), and IL-17A rs3819024(A/G) (AA versus GG: OR = 1.77, 95%CI = 1.39-2.25) and found they were significantly related to the risk of asthma. CONCLUSION: Our systematic review showed that IL-17F rs1889570(C/T), IL-17A rs4711998(A/G) and IL-17A rs3819024(A/G) may be potential risk factors for asthma susceptibility.


Assuntos
Asma/genética , Interleucina-17/genética , Grupo com Ancestrais do Continente Asiático , Asma/etnologia , Grupo com Ancestrais do Continente Europeu , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único
8.
Opt Express ; 22(16): 19262-76, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-25321011

RESUMO

With high-determinacy and no subsurface damage, Magnetorheological Finishing (MRF) has become an important tool in fabricating high-precision optics. But for large mirrors, the application of MRF is restricted by its small removal function and low material removal rate. In order to improve the material removal rate, shorten the processing cycle, we proposed a new MRF concept, named Belt-MRF to expand the application of MRF to large mirrors and made a prototype with a large remove function, using a belt instead of a very large polishing wheel to expand the polishing length. A series of experimental results on Silicon carbide (SiC) and BK 7 specimens and fabrication simulation verified that the Belt-MRF has high material removal rates, stable removal function and high convergence efficiency which makes it a promising technology for processing large aperture optical elements.

9.
PLoS One ; 9(5): e96111, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24798197

RESUMO

Effective assessments of air-pollution exposure depend on the ability to accurately predict pollutant concentrations at unmonitored locations, which can be achieved through spatial interpolation. However, most interpolation approaches currently in use are based on the Euclidean distance, which cannot account for the complex nonlinear features displayed by air-pollution distributions in the wind-field. In this study, an interpolation method based on the shortest path distance is developed to characterize the impact of complex urban wind-field on the distribution of the particulate matter concentration. In this method, the wind-field is incorporated by first interpolating the observed wind-field from a meteorological-station network, then using this continuous wind-field to construct a cost surface based on Gaussian dispersion model and calculating the shortest wind-field path distances between locations, and finally replacing the Euclidean distances typically used in Inverse Distance Weighting (IDW) with the shortest wind-field path distances. This proposed methodology is used to generate daily and hourly estimation surfaces for the particulate matter concentration in the urban area of Beijing in May 2013. This study demonstrates that wind-fields can be incorporated into an interpolation framework using the shortest wind-field path distance, which leads to a remarkable improvement in both the prediction accuracy and the visual reproduction of the wind-flow effect, both of which are of great importance for the assessment of the effects of pollutants on human health.


Assuntos
Monitoramento Ambiental/métodos , Modelos Químicos , Material Particulado/análise , Humanos
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