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1.
Sci Total Environ ; 902: 166008, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544440

RESUMO

Waste dolomite powder (WDP) is a byproduct obtained from dolomite quarries during the preparation of dolomite products. To study the re-utilisation of WDP, an eco-friendly cement-based material was prepared using WDP as a micro-aggregate. The effects of WDP on the early hydration process, microscale characteristics, and life-cycle assessment of cement paste are discussed in this study. The isothermal calorimetry results showed that the incorporating WDP in cement paste accelerated the early hydration process of cement according to the degree of reaction. In this case, the setting time of the cement pastes with WDP was shortened, and the early compressive strength was significantly improved. The results of X-ray diffraction and scanning electron microscopy analysis at early curing ages (1 and 3 d) showed changes in the peak intensity of ettringite and portlandite and a denser microstructure. Mercury intrusion porosimetry tests showed that the middle and large capillary pores were refined by the nucleation and filling effects of WDP. Based on environmental and economic evaluations, the utilisation of WDP reduced energy consumption, CO2 emissions, and economic costs. Compared to the sample without WDP, the energy consumption, CO2 emissions, and economic cost indices were 42 %, 42.69 %, and 39.4 % lower, respectively. Our results may provide valuable references for the re-utilisation of WDP in low-carbonation cement-based materials.

2.
Biomed Environ Sci ; 36(6): 490-500, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37424242

RESUMO

Objective: The study aimed to estimate the benchmark dose (BMD) of coke oven emissions (COEs) exposure based on mitochondrial damage with the mitochondrial DNA copy number (mtDNAcn) as a biomarker. Methods: A total of 782 subjects were recruited, including 238 controls and 544 exposed workers. The mtDNAcn of peripheral leukocytes was detected through the real-time fluorescence-based quantitative polymerase chain reaction. Three BMD approaches were used to calculate the BMD of COEs exposure based on the mitochondrial damage and its 95% confidence lower limit (BMDL). Results: The mtDNAcn of the exposure group was lower than that of the control group (0.60 ± 0.29 vs. 1.03 ± 0.31; P < 0.001). A dose-response relationship was shown between the mtDNAcn damage and COEs. Using the Benchmark Dose Software, the occupational exposure limits (OELs) for COEs exposure in males was 0.00190 mg/m 3. The OELs for COEs exposure using the BBMD were 0.00170 mg/m 3 for the total population, 0.00158 mg/m 3 for males, and 0.00174 mg/m 3 for females. In possible risk obtained from animal studies (PROAST), the OELs of the total population, males, and females were 0.00184, 0.00178, and 0.00192 mg/m 3, respectively. Conclusion: Based on our conservative estimate, the BMDL of mitochondrial damage caused by COEs is 0.002 mg/m 3. This value will provide a benchmark for determining possible OELs.


Assuntos
Coque , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Masculino , Feminino , Animais , Variações do Número de Cópias de DNA , Benchmarking , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , DNA Mitocondrial/genética , Dano ao DNA
3.
Front Physiol ; 13: 995575, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225296

RESUMO

Commercially wrist-worn devices often present inaccurate estimations of energy expenditure (EE), with large between-device differences. We aimed to assess the validity of the Apple Watch Series 6 (AW), Garmin FENIX 6 (GF) and Huawei Watch GT 2e (HW) in estimating EE during outdoor walking and running. Twenty young normal-weight Chinese adults concurrently wore three index devices randomly positioned at both wrists during walking at 6 km/h and running at 10 km/h for 2 km on a 400- meter track. As a criterion, EE was assessed by indirect calorimetry (COSMED K5). For walking, EE from AW and GF was significantly higher than that obtained by the K5 (p < 0.001 and 0.002, respectively), but not for HW (p = 0.491). The mean absolute percentage error (MAPE) was 19.8% for AW, 32.0% for GF, and 9.9% for HW, respectively. The limits of agreement (LoA) were 44.1, 150.1 and 48.6 kcal for AW, GF, and HW respectively. The intraclass correlation coefficient (ICC) was 0.821, 0.216 and 0.760 for AW, GF, and HW, respectively. For running, EE from AW and GF were significantly higher than the K5 (p < 0.001 and 0.001, respectively), but not for HW (p = 0.946). The MAPE was 24.4%, 21.8% and 11.9% for AW, GF and HW, respectively. LoA were 62.8, 89.4 and 65.6 kcal for AW, GF and HW, respectively. The ICC was 0.741, 0.594, and 0.698 for AW, GF and HW, respectively. The results indicate that the tested smartwatches show a moderate validity in EE estimations for outdoor walking and running.

4.
Ecotoxicol Environ Saf ; 182: 109453, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31349105

RESUMO

Telomeres are DNA-protein structures that protect chromosome ends from degradation and fusion, which are shortened by oxidative stress, for example air pollution including benzene, toluene, Coke Oven Emissions (COEs), and so on. As a biomarker of health and disease, telomere length is associated with cardiovascular, diabetes and cancers. The aim of this study was to estimate the effects of COEs exposure on telomere length and the benchmark dose (BMD) of COEs. A total of 542 coke oven workers and 235 healthy controls without exposure to toxicants were recruited. Quantitative PCR was used to determine the telomere length in human peripheral blood leukocytes DNA. Propensity scoring was used to match coke oven workers to healthy controls. Linear regression models and trend tests were used to the relationship between COEs exposure and telomere length. Telomere length in COEs exposed group 0.764 (0.536, 1.092) was significantly shorter than that in the control group 1.064(0.762, 1.438), (P < 0.001). There were significantly dose-response relationships between COEs exposure and telomere damage with telomere length as a biomarker. A BMDL value lower than the present occupational exposure limits (OELs) of COEs exposure was evaluated using the BMD approach in coke oven workers. Our results suggested that shorter telomere length is related to occupational exposure to COEs and the level of COEs exposure lower than the current national OELs in China and many other countries could induce telomere damage.


Assuntos
Poluentes Ocupacionais do Ar/análise , Coque/análise , Exposição Ocupacional/análise , Telômero/efeitos dos fármacos , Adolescente , Adulto , Poluentes Ocupacionais do Ar/toxicidade , Benchmarking , Biomarcadores/análise , Estudos de Casos e Controles , China , Coque/toxicidade , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Telômero/ultraestrutura , Adulto Jovem
5.
Ann Clin Lab Sci ; 47(5): 546-550, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29066480

RESUMO

It has been shown that the single nucleotide polymorphism (SNP) of the rs2735940 site in the human telomerase reverse transcriptase (hTERT) gene is associated with increased cancer risk. The traditional method to detect SNP genotypes is polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). However, there is a limitation to utilizing PCR-RFLP due to a lack of proper restriction enzyme sites at many polymorphic loci. This study used an improved PCR-RFLP method with a mismatched base for detection of the SNP rs2735940. A new restriction enzyme cutting site was created by created restriction site PCR (CRS-PCR), and in addition, the restriction enzyme MspI for CRS-PCR was cheaper than other enzymes. We used this novel assay to determine the allele frequencies in 552 healthy Chinese Han individuals, and found the allele frequencies to be 63% for allele C and 37% for allele T In summary, the modified PCR-RFLP can be used to detect the SNP of rs2735940 with low cost and high efficiency.


Assuntos
Predisposição Genética para Doença , Técnicas de Genotipagem , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Telomerase/genética , Adolescente , Adulto , Alelos , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/economia , Povo Asiático , China , Custos e Análise de Custo , Desoxirribonuclease HpaII/economia , Desoxirribonuclease HpaII/metabolismo , Feminino , Frequência do Gene , Estudos de Associação Genética/economia , Técnicas de Genotipagem/economia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Reação em Cadeia da Polimerase/economia , Telomerase/metabolismo , Fatores de Tempo , Adulto Jovem
6.
Infect Dis Poverty ; 5(1): 102, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27716342

RESUMO

BACKGROUND: This paper seeks to assess the function of malaria control consultation and service posts (MCCSPs) that are located on the border areas of Yunnan province, P.R. China, as a strategy for eliminating malaria among the mobile and migrant population in these areas. METHODS: A retrospective descriptive analytical study was conducted. Blood smear examinations conducted at all MCCSPs in Yunnan from 2008 to 2014 were analysed. A cross-sectional survey was conducted in 2014 to understand how the MCCSPs function and to elucidate the quality of the blood smear examinations that they conduct. RESULTS: Out of the surveyed MCCSPs, 66 % (39/59), 22 % (13/59), and 12 % (7/59) were attached to local township hospitals, village health clinics, and the county centre for disease control and prevention or private clinics, respectively. More than 64 % (38/59) of the posts' staff were part-time workers from township hospitals and village health facilities. Less than 31 % (18/59) of the posts' staff were full-time workers. A total of 35 positive malaria cases were reported from seven MCCSPs in 2014. Four MCCSPs were unable to perform their functions due to under staffing in 2014. There was a small fluctuation in blood smear examinations from January 2008 to June 2009, with two peaks during the period from July 2009 to October 2010. The number of blood smear examinations has been increasing since 2011. The yearly mean number of blood smear examinations in each post increased from 44 per month in 2011 to 109 per month in 2014, and the number of positive malaria cases detected by blood smear examinations has declined (χ 2 = 90.67, P = 0.000). The percentage of people from Yingjiang county getting blood smear examinations increased between 2008 and 2014, while percentages of the mobile population including Myanmar people, people from other provinces, and people from other Yunnan counties getting blood smear examinations decreased. CONCLUSION: MCCSPs face challenges in the phase of malaria elimination in Yunnan, China. New case detection strategies should be designed for MCCSPs taking into account the current trends of migration.


Assuntos
Instalações de Saúde/estatística & dados numéricos , Malária/prevenção & controle , Encaminhamento e Consulta/estatística & dados numéricos , Coleta de Amostras Sanguíneas/estatística & dados numéricos , China , Estudos Transversais , Humanos , Estudos Retrospectivos , Migrantes/estatística & dados numéricos
7.
Biochemistry (Mosc) ; 81(6): 624-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27301291

RESUMO

Protection of telomeres protein 1 (POT1) plays pivotal roles in protection of chromosome ends and regulation of telomere length with other telomere binding proteins; its genetic polymorphisms are associated with many diseases. In this study, we explored a novel PCR-RFLP method for typing the single nucleotide polymorphism (SNP) rs1034794 of the human POT1 gene. A new restriction enzyme site was introduced into a POT1 gene amplification product by created restriction site PCR (CRS-PCR). One primer was designed based on changed sequence; after PCR amplification, a new restriction enzyme site for AluI was introduced into the PCR products. One hundred and seventy eight samples from Han Chinese individuals were tested to evaluate this new method. The 3'-end of the forward primer was next to the polymorphic site, and the third base from the 3'-end was the mismatched base A. The final PCR product contained the AGCT sequence (AluI recognition site) when the ancestral POT1 alleles were amplified. The data obtained with the new method perfectly matched those obtained with the sequencing method. Thus, CRS-PCR is a new low-cost and high-efficiency alternative for rs1034794 typing.


Assuntos
Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Proteínas de Ligação a Telômeros/genética , Alelos , Povo Asiático/genética , Sequência de Bases , China , Análise Mutacional de DNA , Enzimas de Restrição do DNA/economia , Enzimas de Restrição do DNA/metabolismo , Genótipo , Humanos , Complexo Shelterina
8.
Ying Yong Sheng Tai Xue Bao ; 27(8): 2717-2728, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29733162

RESUMO

Quantitative assessment of urban thermal environment has become a focus for urban climate and environmental science since the concept of urban heat island has been proposed. With the continual development of space information and computer simulation technology, substantial progresses have been made on quantitative assessment techniques and methods of urban thermal environment. The quantitative assessment techniques have been developed to dynamics simulation and forecast of thermal environment at various scales based on statistical analysis of thermal environment on urban-scale using the historical data of weather stations. This study reviewed the development progress of ground meteorological observation, thermal infrared remote sensing and numerical simulation. Moreover, the potential advantages and disadvantages, applicability and the development trends of these techniques were also summarized, aiming to add fundamental knowledge of understanding the urban thermal environment assessment and optimization.


Assuntos
Cidades , Clima , Simulação por Computador , Temperatura Alta , Tecnologia de Sensoriamento Remoto , Tempo (Meteorologia)
9.
Huan Jing Ke Xue ; 30(10): 2872-8, 2009 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-19968100

RESUMO

Watershed models provide a cost-effective and efficient means of estimating the pollutant loadings entering surface waters, especially when combined with traditional water quality sampling and analyses. But there have often been questions about the accuracy or certainty of models and their predictions. The main goal of this study was to evaluate the performance of AnnAGNPS (Annualized AGricultural NonPoint Source)Pollution Model, in simulating runoff, sediment loading and nutrient loadings under Three Gorges Reservoir area. Most of model input parameters were sourced from Zigui Forest Ecology Station in Three Gorges Reservoir area, State Forestry Administration. Data year 2003 was used for calibration while data year 2004 was used for validation of the model. The whole evaluation consisted of determining the coefficient of determination (R2), Nash-Sutcliffe coefficient of efficiency (E), and the percentage volume error (VE). Results showed that the model predicted the daily runoff volume within the range of acceptable accuracy. The runoff on a daily basis was underpredicted by 5.0% with R2 of 0.93 (p < 0.05) during calibration and underpredicted by 6.7% with R2 of 0.90 (p < 0.05) during validation. But sediment loading was able to produce a moderate result. The model underpredicted the event-based sediment loading by 15.1% with R2 of 0.63 (p < 0.05) during calibration and 26.7% with R2 of 0.59 (p < 0.05) during validation. For the events of small magnitude, the model generally overpredicted sediment loading, while the opposite was true for larger events. Nitrogen loading prediction was slightly better with R2 = 0.68 (p < 0.05), and phosphorus loading performance was slightly poor with R2 = 0.65 (p < 0.05). In general, the model performs well in simulating runoff compare to sediment loading and nutrient loadings, and as a watershed management tools it can be used for Three Gorges Reservoir area conditions that with mixed types of land uses and steep slopes.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Monitoramento Ambiental , Modelos Teóricos , Árvores/crescimento & desenvolvimento , Poluição da Água/análise , China , Sedimentos Geológicos/química , Rios , Solo/análise , Movimentos da Água
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