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The risk of human exposure to particulate novel brominated flame retardants (NBFRs) in the atmosphere has received increasing attention from scientists and the public, but currently, there is no reliable approach to predict the intake of these compounds on the basis of their size distribution. Here, we develop a reliable approach to predict the size-dependent inhalation intake of particulate NBFRs, based on the gas/particle (G/P) partitioning behavior of the NBFRs. We analyzed the concentrations of eight NBFRs in 363 size-segregated particulate samples and 99 paired samples of gaseous and bulk particles. Using these data, we developed an equation to predict the G/P partitioning quotients of NBFRs in particles in different size ranges (KPi) based on particle size. This equation was then successfully applied to predict the size-dependent inhalation intake of particulate NBFRs in combination with an inhalation exposure model. This new approach provides the first demonstration of the effects of the temperature-dependent octanol-air partitioning coefficient (KOA) and total suspended particle concentration (TSP) on the intake of particulate NBFRs by inhalation. In an illustrative case where TSP = 100 µg m-3, inhalation intake of particulate NBFRs exceeded the intake of gaseous NBFRs when log KOA > 11.4.
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Retardadores de Llama , Atmósfera , Polvo/análisis , Monitoreo del Ambiente , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis , HumanosRESUMEN
OBJECTIVE: To explore the expression of T cell immunoglobulin and mucin domain protein 3 (Tim-3) on CD56(+) NK cells in peripheral blood and its correlation with liver fibrosis indicators in patients with advanced schistosomiasis. METHODS: Tim-3 expression on CD6(+) NK cells from 28 patients with advanced schistosomiasis and 30 healthy controls was determined by flow cytometry. The serum levels of IFN-y and IL-4 were detected by enzyme-linked immunosorbent assay (ELISA). Fibroscan analyzer was used for liver stiffness measurement (LSM) to determine the extent of liver fibrosis. Four serological indicators of liver fibrosis, collagen type III N-peptide (PIIP N-P), Laminin (LN), collagen IV (CIV) and hyaluronic acid (HA) were measured by the Automated Chemiluminescence Immunoassay Analyzer. RESULTS: Flow cytometry analysis showed that Tim-3 expression on CD56(+) NK cells in advanced schistosomiasis patients was (62.3±11.4)%, significantly higher than that (52.1±6.5)% (P< 0.01). In patients with advanced schistosomiasis and the healthy controls, the levels of PIIIP N-P were (86.5±29.5) ng/mL and (22.0±7.8) ng/mL, LN (49.3±21.5) ng/mL and (20.4±6.3) ng/mL, CIV (67.5±22.3) ng/mL and (22.0±3.9) ng/mL, HA (645.9±483.1) ng/mL and (54.7±27.7) ng/mL, respectively. There were significant differences in all these indicators between the two groups (P<0.05). The levels of IFN-y were (93.9?20.1) ng/L and (107.7?24.6) ng/L, and those of IL-4 were (46.6±11.8) ng/L and (28.9±8.9) ng/L respectively in patients with advanced schistosomiasis and the healthy controls, both with significant differences (P<0.05). Spearman nonparametric correlation analysis showed that Tim-3 expression on CD56(+) NK cells in patients was positively correlated with the levels of LSM, PIIIP N-P, LN, CIV and IL-4 (r=0.528-0.834, P<0.01), but negatively with serum IFN-y (r=-0.501, P<0.01). No correlation was found with the HA level (r=0.352, P>0.05). CONCLUSION: The expression of Tim-3 on peripheral CD56(+) NK cells increases in patients with advanced schistosomiasis compared with the healthy controls, and it positively correlates with the levels of LSM, PIIIP N-P, LN, CIV and IL-4, four indicators of liver fibrosis.
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Células Asesinas Naturales/metabolismo , Cirrosis Hepática/parasitología , Proteínas de la Membrana/metabolismo , Esquistosomiasis/metabolismo , Estudios de Casos y Controles , Colágeno Tipo IV/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Receptor 2 Celular del Virus de la Hepatitis A , Humanos , Ácido Hialurónico/metabolismo , Interferón gamma/sangre , Interleucina-4/sangre , Laminina/metabolismo , Cirrosis Hepática/metabolismo , Fragmentos de Péptidos/metabolismo , Procolágeno/metabolismoRESUMEN
Circular RNAs (CircRNAs) have been reported to play key roles in the progression of various cancers, including thyroid cancer (TC). Transcription factor 1 (SP1) promotes the development of thyroid cancer. This study aims at investigating the expression level of Circ0005654 in combination with Transcription factor1 (SP1) in patients with TC for diagnostic and therapeutic purposes. A total of 76 patients with thyroid cancer underwent radical surgery. Intraoperatively, thyroid cancer tissues and paired adjacent tissues and the corresponding clinicopathological data were collected. The expression of SP1 and ß-catenin in thyroid cancer and adjacent tissues was determined by immunohistochemistry (IHC) while the Circ0005654 expression level was measured by semiquantitative real-time polymerase chain reaction (sqRT-PCR). Then, we compared the variability of Circ0005654, SP1, and Wnt/ß-catenin expression in cancerous and adjacent tissues and determined the relationship between the correlation analysis and the clinicopathological features of the thyroid cancer patients. The diagnostic value of Circ0005654 in thyroid cancer tissues was analyzed with the help of the receiver operating characteristic (ROC) curve, counting the 3-year postoperative survival rate, and analyzing the effect of Circ0005654 and SP1 protein levels on the 3-year survival rate of the patients. sqRT-PCR showed that the expression level of Circ0005654 in thyroid cancer tissue was significantly higher than that of adjacent tissues. The area under the ROC of Circ0005654 was 0.9553, 95% confidence interval: (0.9211-0.9895) with a cutoff value of 0.7895, a sensitivity of 92.11%, and a specificity of 86.84%. The IHC results showed that the expression level of SP1, ß-catenin, and Wnt was higher in cancer tissues than in adjacent tissues; Circ0005654, SP1, Wnt/ß-catenin expression levels were associated with tumor diameter, lymph node metastasis, TNM stage, and envelope invasion (all P < .05). According to the Circ0005654 expression level in thyroid cancer tissue, the 3-year survival rate of the high expression group was 77.5% and 94.4% in the low expression group with a statistically significant difference; the 3-year survival rate of SP1 positive and negative patients was 78.6% and 100%, respectively, with the data being significantly different. Circ0005654 may serve as a potential biomarker for thyroid cancer diagnosis and may be involved in the development of thyroid cancer.
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Neoplasias de la Tiroides , beta Catenina , Humanos , Estudios de Casos y Controles , beta Catenina/genética , beta Catenina/metabolismo , Pronóstico , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/cirugía , Biomarcadores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Factor de Transcripción Sp1/genética , Factor de Transcripción Sp1/metabolismoRESUMEN
The floating catkins generated by willow and poplar trees have been criticized for spreading germ and causing fire for decades. It has been found that catkins are with a hollow tubular structure, which made us wonder if the floating catkins can adsorb atmospheric pollutions. Thus, we conducted a project in Harbin, China to investigate whether and how willow catkins could adsorb atmospheric polycyclic aromatic hydrocarbons (PAHs). The results suggest that both the catkins floating in the air and on the ground preferred to adsorb gaseous PAHs rather than particulate PAHs. Moreover, 3- and 4-ring PAHs were the dominating compositions adsorbed by catkins, which significantly increased with exposure time. The gas/catkins partition (KCG) was defined, which explained why 3-ring PAHs are more easily adsorbed by catkins than by airborne particles when their subcooled liquid vapor pressure is high (log PL > -1.73). The removal loading of atmospheric PAHs by catkins were estimated as 1.03 kg/year in the center city of Harbin, which may well explain the phenomenon that levels of gaseous and total (particle + gas) PAHs are relatively low in the months with catkins floating reported in peer-reviewed papers.
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OBJECTIVE: To evaluate the effect of comprehensive control strategy of schistosomiasis with emphasis on infection source control in Anhui province. METHODS: Forty endemic villages in Guichi district, Chizhou city, Anhui province were selected as national pilot villages in the years from 2006 to 2008, and another 10 provincial pilot villages were respectively selected from 10 highly endemic villages in 7 cities in 2007. The comprehensive infection source control measures, including "replace cattle with machines", "raise livestock in pens", "improve the sanitary toilets", "supply safe water " and so on were carried out among the above pilot villages. At the end of 2008, 13 national pilot villages and 6 provincial pilot villages were selected to investigate the popularity of schistosomiasis, and the effect of the comprehensive control strategy in those villages were compared. RESULTS: After implementing the comprehensive control strategy, the infectious rate of schistosomiasis in national pilot villages decreased from 4.57% (487/10 659) to 1.76% (147/8370), with the reduction rate at 61.49%, whose difference showed statistical significance (χ(2) = 115.16, P < 0.01); and the density of infected snails decreased from 0.0067/0.1 m(2) to 0.0008/0.1 m(2), the infectious rate of snails decreased from 0.28% to 0.04%, whose reduction rates were 88.06% and 85.71% respectively. While as to the provincial pilot villages, the infectious rate of schistosomiasis decreased from 1.27% (54/4254) to 0.21% (14/6592), with the reduction rate at 83.46%, whose difference showed statistical significance (χ(2) = 94.57, P < 0.01); and the density of infected snails decreased from 0.0025/0.1 m(2) to 0.0003/0.1 m(2), the infection rate of snails decreased from 0.13% to 0.05%, whose reduction rates were 88.00% and 61.54% respectively. CONCLUSION: The comprehensive control strategy with emphasis on infection source control implemented in marshland and lake regions can effectively control the transmission of schistosomiasis.
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Control de Infecciones/métodos , Esquistosomiasis/epidemiología , Esquistosomiasis/prevención & control , Caracoles/parasitología , Animales , China/epidemiología , Reservorios de Enfermedades/parasitología , Humanos , Ganado , Proyectos Piloto , Salud Rural , Esquistosomiasis/parasitologíaRESUMEN
OBJECTIVE: To analyze the impact of large hydraulic projects on schistosomiasis transmission and evaluate the transmission risk in potential endemic areas. METHODS: During 2008-2010, surveillance on risk factors related to schistosomiasis transmission and risk assessment were carried out in potential endemic sites in counties of Xuyu, Hongze, Jinhu, and Gaoyou in Jiangsu Province, Weishan County in Shangdong, Qianjiang City and Yiling District of Yichang City in Hubei, Juchao District of Chaohu City in Anhui Province, Wanzhou and Kaixian in Chongqing in Three Gorges Dam region or passed by South-to-North Water Diversion Project and Zhangjiagang City in Jiangsu Province located in lower reach of Yangtze River. At least one fixed and three temporary monitoring sites were set in each county (city or district). Local inhabitants aged 6-65 years old were screened by indirect haemagglutination assay (IHA) or ELISA, and the sero-positives were tested by Kato-Katz or miracidium hatching techniques to investigate possible infection in 2008. The endemic status of schistosomiasis in mobile population was surveyed every year during 2008-2010. Infection status in livestocks was surveyed in Juchao, Qianjiang, Gaoyou and Wanzhou Counties in 2008-2010. Oncomelania hupensis distribution was investigated in risky and suspicious areas. Snail spreading investigation was conducted through salvaging floater and snails-inducing by straw curtains in rivers connected with Yangtze River. RESULTS: 8 256 local inhabitants were investigated by serological tests with a positive rate of 0.7% (60/8 256). Among the 60 serologically positive subjects, 55 individuals were examined by stool examination but none of them was egg positive. The antibody prevalence rate of migrating population in 2008-2010 was 2.0%, 1.4%, and 1.7%, respectively, with no significant difference (chi2 = 3.57, P > 0.05). Among the serologically positive subjects, egg-positive cases were found in migrating population in Juchao District each year and one case was found in Jinhu County in 2010. Oncomelania snails were only found in in Jinhu and Gaoyou without infected ones. A lot of aquatic shell-fish and snails were collected in the water floater and straw curtain without Oncomelania snails. CONCLUSION: Schistosomiasis is not endemic in the original nonendemic areas in Three Gorges Dam region and areas passed by South-to-North Water Diversion Project until now, but potential risk of transmission exists. Long term surveillance scheme on schistosomiasis should be established with varied monitoring factors in different category areas.
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Ambiente , Esquistosomiasis Japónica/prevención & control , Animales , China/epidemiología , Humanos , Medición de Riesgo , Esquistosomiasis , Esquistosomiasis Japónica/epidemiología , Esquistosomiasis Japónica/transmisión , Caracoles/parasitologíaRESUMEN
Deep learning-based object counting models have recently been considered preferable choices for plant counting. However, the performance of these data-driven methods would probably deteriorate when a discrepancy exists between the training and testing data. Such a discrepancy is also known as the domain gap. One way to mitigate the performance drop is to use unlabeled data sampled from the testing environment to correct the model behavior. This problem setting is also called unsupervised domain adaptation (UDA). Despite UDA has been a long-standing topic in machine learning society, UDA methods are less studied for plant counting. In this paper, we first evaluate some frequently-used UDA methods on the plant counting task, including feature-level and image-level methods. By analyzing the failure patterns of these methods, we propose a novel background-aware domain adaptation (BADA) module to address the drawbacks. We show that BADA can easily fit into object counting models to improve the cross-domain plant counting performance, especially on background areas. Benefiting from learning where to count, background counting errors are reduced. We also show that BADA can work with adversarial training strategies to further enhance the robustness of counting models against the domain gap. We evaluated our method on 7 different domain adaptation settings, including different camera views, cultivars, locations, and image acquisition devices. Results demonstrate that our method achieved the lowest Mean Absolute Error on 6 out of the 7 settings. The usefulness of BADA is also supported by controlled ablation studies and visualizations.
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OBJECTIVE: To isolate and purify agglutinin from Oncomelania hupensis snail and determine its molecular weight. METHODS: Agglutinin was preliminarily isolated from snail tissue homogenate by 0%-40% saturated ammonium sulfate, and then successively purified with Sephadex G-75 gel filtration and Sepharose 4B affinity chromatography. Bradford assay was used to determine the protein content. The agglutination activity was determined by rabbit erythrocytes. The purity of agglutinin preparations was assessed by SDS-PAGE. The molecular weight of agglutinin subunit was determined by Sephadex G-75 gel filtration. RESULTS: The specific activity of snail tissue homogenate was 21.74 titer/mg. After ammonium sulfate precipitation, Sephadex G-75 gel filtration and Sepharose 4B affinity chromatography, the specific activity of snail agglutinin from the homogenate solution increased to 61.93 titer/mg, 75.89 titer/mg and 963.86 titer/mg, respectively. SDS-PAGE analysis indicated that snail agglutinin (M, 53,000) was purified by Sephadex G-75 gel filtration and Sepharose 4B chromatography. The molecular weight of the snail agglutinin produced by Sephadex G-75 gel filtration was Mr 78,000. CONCLUSION: Combined use of salt fractionation, gel filtration and affinity chromatography can be efficient for extraction and purification of agglutinin from Oncomelania hupensis species. The snail agglutinin is characterized as mono subunit protein with a molecular weight of Mr 78,000.
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Aglutininas/química , Aglutininas/aislamiento & purificación , Caracoles/química , Animales , China , Cromatografía de Afinidad , Peso MolecularRESUMEN
The objective of this study was to explore the differences of five methods for evaluating the PM retention capacity of leaves based on the same experimental materials and leaf area measurement method and to summarize the advantages and disadvantages of each method. In this study, four tree species (Pinus tabuliformis, Platycladus orientalis, Ginkgo biloba, and Platanus occidentalis), which are common in Beijing and have greatly different leaf characteristics, were selected as the research objects. The mass subtraction method (MS), the membrane filter method (MF), the aerosol regenerator method(AR), the scanning electron method (SEM), and the elution weighing method coupled with a particle size analysis based on ultrasonic cleaning (ultrasonic-EWPA) were used to evaluate the PM retention capabilities and characteristics of the leaves of the four tree species. The total time needed and the total cost were measured simultaneously during the evaluation process. The results showed that although the values of PM retention efficiency obtained by different methods were quite different, the ranks of the efficiency of four tree species obtained by different methods were the same or partially the same. Additionally, the results obtained by the methods with the same or similar principles were more overlapped (AR and SEM had the most overlapped results). In addition, 89% of the species ranks of the same index obtained by each method were P. orientalis > P. tabuliformis > P. occidentalis > G. biloba, and the remaining 11% were P. occidentalis > G. biloba > P. orientalis > P. tabuliformis. Among the five methods, ultrasonic-EWPA was the one with the largest number of indexes and the highest cost, and MS was the one with the least number of indexes and the lowest cost. The one that needed most time was MF, while the one that needed the least time was AR. ultrasonic-EWPA and SEM are high input and high output methods. That is to say, although they needed more time and cost, they can prove more information; however, MS was opposite, which resulted in less information but lower time and cost needed. So, it is suitable for roughly evaluating the total PM retention capacities of trees; MF had a medium amount of information, low cost, but required too much time, which needs to be weighed and balanced before selecting this method. The AR method had strict requirements for equipment and parameters and should be used with caution. The results of this study can provide a comprehensive and detailed scientific basis for researchers to choose specific methods in the future.
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Contaminantes Atmosféricos , Material Particulado , Contaminantes Atmosféricos/análisis , Beijing , Monitoreo del Ambiente , Material Particulado/análisis , Hojas de la Planta/químicaRESUMEN
Elimination of the intermediate snail host of Schistosoma is the most effective way to control schistosomiasis and the most important first step is to accurately identify the snail habitats. Due to the substantial resources required for traditional, manual snail-searching in the field, and potential risk of miss-classification of potential snail habitats by remote sensing, more convenient and precise methods are urgently needed. Snail data (N = 15,000) from two types of snail habitats (lake/marshland and hilly areas) in Anhui Province, a typical endemic area for schistosomiasis, were collected together with 36 environmental variables covering the whole province. Twelve different models were built and evaluated with indices, such as area under the curve (AUC), Kappa, percent correctly classified (PCC), sensitivity and specificity. We found the presence-absence models performing better than those based on presence-only. However, those derived from machine-learning, especially the random forest (RF) approach were preferable with all indices above 0.90. Distance to nearest river was found to be the most important variable for the lake/marshlands, while the climatic variables were more important for the hilly endemic areas. The predicted high-risk areas for potential snail habitats of the lake/marshland type exist mainly along the Yangtze River, while those of the hilly type are dispersed in the areas south of the Yangtze River. We provide here the first comprehensive risk profile of potential snail habitats based on precise examinations revealing the true distribution and habitat type, thereby improving efficiency and accuracy of snail control including better allocation of limited health resources.
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Ecosistema , Monitoreo del Ambiente/métodos , Caracoles/parasitología , Animales , China/epidemiología , Reservorios de Enfermedades/parasitología , Bosques , Sistemas de Información Geográfica , Lagos , Ríos , Imágenes Satelitales , Schistosoma , Esquistosomiasis/epidemiología , Sensibilidad y EspecificidadRESUMEN
We study the seasonal variations of δ13C ratios in aerosol fine particulate matter (PM2.5) using 91 PM2.5 samples collected from Xinxiang, China, during the summer and winter in 2017. Mass concentrations of total carbon (TC), water soluble ions, and stable carbon isotope ratios (δ13C) were determined. The mean concentrations of TC in the summer and winter were 11.78 µg·m-3 and 26.6 µg·m-3, respectively. The δ13C ratio in the summer ranged from -27.70 to -25.22. The daily δ13C ratio fluctuated in the first half of the summer months (mean -26.96), whereas the δ13C ratio in the second half of the summer was relatively stable (mean -25.69). The number of fires in the study area during the first half of the summer was quite different to the number during the second half of the summer, meanwhile, there was a positive correlation between the Knss+ concentration and the TC mass concentration (R2=0.62, P<0.01). This indicates that biomass burning most likely contributed to variations in δ13C. During the winter there was a significant negative correlation between winter RH and the TC/PM2.5 mass ratio (R2=0.68, P<0.01), which suggests that SOA growth was dominant in the early stage of haze development, whereas the pollution period was dominated by SIA components. The ratio of δ13C ranged from -26.72 to -23.49, and there was a difference between the variation of the δ13C ratio in haze episode (when it was mainly enriched in the development stage) to that in the stage dominated by depletion.
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Gas/particle (G/P) partition quotients of semi-volatile organic compounds (SVOCs) for bulk air have been widely discussed in experimental and theoretical contexts, but research on size-resolved G/P partition quotients (KPi) are scarce and limited in scope. To investigate G/P partition behavior of polybrominated diphenyl ethers (PBDEs) for size-segregated particles in the atmosphere, 396 individual size-segregated particulate samples (36 batches × 11 size-ranges), and 108 pairs of concurrent gaseous and bulk particulate samples were collected in Harbin, China. A steady-state equation based on bulk particles is derived to determine G/P partition quotients of PBDEs for size-segregated particles, which depends on the organic matter contents of size-segregated particles (fOMi). This equation can well predict KPi with knowledge of bulk partition quotient (KPS), ambient temperature, and fOMi, the results of which match well with monitoring data in Harbin and other published data collected in Shanghai and Guangzhou of China and Thessaloniki of Greece, and remedies a defect of over-estimate KPi for high-brominated PBDEs by the previous equation. In particular, the new equation contributes to obtaining the PBDEs concentrations in all atmospheric phase from partial phase, then provides a credible path to evaluate healthy exposure dose from the airborne PBDEs, by co-utilization with exposure models.
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In order to explore the characteristics of PM2.5 concentration and water-soluble inorganic ions in Zhengzhou City, a total of 170 PM2.5 samples were collected in the spring, summer, autumn, and winter seasons of 2016, with 30 days continuous sampling during each season. The mass concentration of PM2.5 was analyzed gravimetrically, water-soluble inorganic ions were determined by ion chromatography, and principle component analysis was employed for source apportionment. The results showed that the mass concentration of PM2.5 was 150.72µg·m-3 during the sampling period. The mass concentration was highest in winter and lowest in summer, and that of autumn is higher was higher than that of spring. The ions SO42-, NO3-, and NH4+ were the major WSIs found in PM2.5, accounting for 92.55%, 92.94%, 93.06%, and 93.15% of the total amount of the seven ions found in spring, summer, autumn, and winter, respectively. The anion-to-cation ratio was 0.886, which indicated that PM2.5 was slightly alkaline in Zhengzhou. Secondary inorganic species, including NH4+, NO3-, and SO42- were the major components of the water-soluble ions. These ions most likely existed in the form of NH4NO3 and (NH4)2SO4 during spring and summer, while they were present as NH4NO3, (NH4)2SO4 and NH4HSO4 in autumn. In addition to these three forms, NH4Cl or other forms may exist in winter. Industrial emissions, combustion, secondary transformation, soil, and construction dust were the major sources of the water-soluble ions in PM2.5.
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To study the interannual variations of chemical composition and source apportionment, a field campaign was carried out to collect the PM2.5 temperance sample during the winter of 2015 and the winter of 2016 in Xinxiang urban areas. PM2.5 mass concentration, metal elements, and the water-soluble ions were determined and meteorological factors were recorded simultaneously. The results showed that the daily mean concentrations of PM2.5 indicated serious pollution with values of 226 µg·m-3 and 224 µg·m-3 in 2015 and 2016, respectively. The Cd and Pb elements in PM2.5 were significantly enriched, with EF more than 1000. However, compared with 2015, the enrichment effect of most metal elements showed a trend of decrease in 2016. The water-soluble ions were mainly composed of SO42-, NO3-, and NH4+. The results showed a trade-off effect between metal elements and water-soluble ions in the two study periods. The results of PCA and PMF analyses show that there were four main emission sources in Xinxiang city in winter, namely dust, secondary source, industrial source, and fossil fuel combustion source. Moreover, the main sources of PM2.5 was the mixed source of soil and building dust and secondary aerosol pollution, with contributions of 37.46% and 34.94% in the winters of 2015 and 2016, respectively.
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To accurately and quantitatively evaluate the mass and particle size distribution of water-soluble and water-insoluble particulate matters (PM) on the surface of tree leaves, which would help to improve the accuracy of quantitative assessment of the retention ability of urban trees to atmospheric particles, we collected leaf samples from three broadleaved tree species [Ginkgo (Ginkgo biloba), Chinese scholar tree (Sophora japonica) and weeping willow (Salix babylonica)] and two conifer species [Chinese pine (Pinus tabuliformis) and China savin (Sabina chinensis)] 14 d after the rain (rainfall>15 mm). The PMs retained on leaves were collected by a succeeding procedure of washing + brushing (WC+BC) and ultrasonic cleaning (UC). Then, the extracts at each step were divided into water-soluble and water-insoluble PMs through centrifuge. The mass of water-soluble and water-insoluble particles were dry weighted. Then, the water-soluble and water-insoluble particles were dissolved by anhydrous ethanol and deionized water to measure the particle size distribution. The mass of water-soluble and water-insoluble particles with different particle sizes was calculated. Results showed that the mass (proportion) of water-soluble PMs retained on leaf surfaces of broad-leaved and conifer species were 480.61 (52.3%) and 438.91 (47.7%) mg·m-2, respectively, while that for water-insoluble PMs were 97.93 (12.0%) and 715.84 (88.0%) mg·m-2, respectively. The particle size distribution of water-soluble particles on the leaves of the five tree species showed the unimodal curve with mean size of 40.36 µm. Water-insoluble particles on leaves showed multimodal distribution, with mean size of 105.65 µm. S. japonica and G. biloba had higher PM retention ability in regions suffering with more water-soluble PM pollution, while S. chinensis had higher retention ability to water-insoluble PMs.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Hojas de la Planta/química , Árboles , China , Tamaño de la Partícula , AguaRESUMEN
To study the pollution characteristics, sources, and transportation process of PM2.5 and its chemical compositions in the Zhengzhou-Xinxiang region, PM2.5 samples were collected using a middle volume sampler, in Zhengzhou and Xinxiang urban areas for 30 consecutive days during the winter of 2016. The mass concentration of PM2.5 was measured gravimetrically. 17 trace metals were determined by inductively coupled plasma-mass spectrometry (ICP-MS), and 7 water-soluble ions were determined by ion chromatography. The enrichment factor (EF) method and principal component analysis were employed to determine the source apportionment. The results showed that the daily mean PM2.5 mass concentration during the winter sampling period of 2016 in Xinxiang and Zhengzhou was 223.87 µg·m-3 and 226.67 µg·m-3, respectively, which indicated that pollution levels were relatively high in both cities. The concentration of three macro elements (Al, Ca, and Fe) accounted for 50% of the total metal elements in both cities, while the heavy metals concentration was higher in Xinxiang than in Zhengzhou. The EFs of Cd, Ag, and Pb in Xinxiang were far higher than 1000, while only Cd was higher than 1000 in Zhengzhou. NO3-, SO42-, and NH4+ were the main ions in the two cities. They exceeded 94% of total water-soluble ions and existed in the forms of (NH4)2SO4 and NH4NO3. The principle component analysis showed that the main contributors to PM2.5 were a mixture of biomass combustion and secondary aerosol in Xinxiang, and a mixture of coal combustion and traffic emissions in Zhengzhou, accounting for 34.94% and 33.99% of total PM2.5 emissions, respectively.
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OBJECTIVE: To explore the risk factors of cerebral schistosomiasis japonica. METHODS: A total of 37 confirmed cases, diagnosed during 1999-2004 in Anhui Province, were involved in the study as case group. Three controls for each case were selected from the general population either without schistosomiasis, with chronic schistosomiasis or with acute schistosomiasis. The relevant risk factors on the disease were analyzed. RESULTS: Four factors with labour intensity, physical, economical and nutritional conditions before illness between case group and normal control group, 7 factors including epilepsy history, hypersensitivity, intensity and times of infection between case group and acute schistosomiasis control group, 10 factors including intensity of infection, times of infection and treatment between case group and chronic schistosomiasis control group, all showed statistical significance (p < 0.05) . Five factors showed statistical significance (p < 0.05) between case group and the 3 control groups. CONCLUSION: The intensity of schistosome infection and treatment history are the main risk factors for cerebral schistosomiasis, and the physical and psychosocial conditions of the patients show some effect on the disease.
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Encefalopatías/etiología , Encefalopatías/parasitología , Esquistosomiasis Japónica/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , China/epidemiología , Humanos , Persona de Mediana Edad , Factores de Riesgo , Adulto JovenRESUMEN
Anhui Province has been one of typical epidemic areas of schistosomiasis in East China as a wide range of large lake and marshland regions provide an ideal environment for growth and reproduction of the intermediate snail host. With the completion of the Yangtze River-Huaihe River Water Transfer Project (YHWTP), launched by the end of 2016, the epidemic areas are expected to expand and controlling schistosomiasis remains a challenge. Based on annual surveillance data at the county level in Anhui for the period 2006-2015, spatial and temporal cluster analyses were conducted to assess the pattern of risk through spatial (Local Moran's I and flexible scan statistic) and space-time scan statistic (Kulldorff). It was found that schistosomiasis sero-prevalence was dramatically reduced and maintained at a low level. Cluster results showed that spatial extent of schistosomiasis contracted, but snail distribution remained geographically stable across the study area. Clusters, both for schistosomiasis and snail presence, were common along the Yangtze River. Considering the effect of the ongoing YHWTP on the potential spread of schistosomiasis, Zongyang County and Anqing, which will be transected by the new water-transfer route, should be given a priority for strengthened surveillance and control. Attention should also be paid to Guichi since it is close to one of the planned inlets of the YHWTP.
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Ríos/parasitología , Esquistosomiasis Japónica/epidemiología , Caracoles/parasitología , Análisis Espacio-Temporal , Distribución Animal , Animales , Anticuerpos Antihelmínticos/sangre , China , Análisis por Conglomerados , Conservación de los Recursos Hídricos , Estudios Transversales , Humanos , Prevalencia , Schistosoma japonicum , Estudios Seroepidemiológicos , Encuestas y CuestionariosRESUMEN
Under a condition of good air quality (AQI:55-90, PM10:37-97 µg·m-3, PM2.5:17-76 µg·m-3), six groups of 54 samples were collected using an Andersen cascade impactor from both the indoor and outdoor stations in Beijing and Xinxiang from June to August in 2016. The samples were digested by microwave digestion, and nine heavy metal elements (Pb, Cr, Ni, Cu, Zn, As, Cd, Mn, and Co) in the atmospheric particles were determined with an inductively coupled plasma source mass spectrometer (ICP-MS). The results showed that the enrichment index (0-3) of most elements were low in both cities except for Cd[15.0 (Beijing) and 8.47 (Xinxiang)]. Cr, Co, Cu, and Mn in the atmospheric particles from Beijing park, Cd, Pb, and Mn in the atmospheric particles from the Beijing office, Cr, Co, Ni, and As in the atmospheric particles from Xinxiang park, and all nine heavy metal elements in the atmospheric particles from roads in both cities were found to be more concentrated in the coarse fractions; however, Pb, Zn, Cd, Ni, and As in the atmospheric particles from Beijing park, Co, Zn, Ni, Cr, As, and Cu in the atmospheric particles from the Beijing office, Pb, Zn, Cd, Cu, and Mn in the atmospheric particles from Xinxiang park, and all nine metal elements in the atmospheric particles from the Beijing office showed the opposite pattern. The result of a human health risk assessment indicated that the carcinogenic risk of the five carcinogenic elements were all less than 10-4, but a lower potential cancer risk would also occur under long term exposure. For the four non-carcinogenic elements (Pb, Zn, Mn, and Cu), the non-carcinogenic health risk values of Pb, Zn, Mn, and Cu in the atmospheric particulates in Beijing were all far less than 1, which means the corresponding non-carcinogenic risk was negligible; and, except for Mn, there was no obvious non-carcinogenic risk from Pb, Zn, and Cu in the atmospheric particles of Xinxiang.
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Contaminantes Atmosféricos/análisis , Metales Pesados/análisis , Beijing , Ciudades , Monitoreo del Ambiente , Humanos , Tamaño de la Partícula , Medición de RiesgoRESUMEN
OBJECTIVE: To investigate the possibility of spread of snails and transmission of schistosomiasis japonica due to the construction of water transfer project from Yangtze River to Huaihe River. METHODS: In order to understand the current endemic situation of schistosomiasis in the project area, the distribution of snails was surveyed by routine methods, level of anti-schistosome antibody in human sera was detected by indirect haemagglutination test (IHA), and the prevalence of schistosomiasis in cattle was detected by egg hatching method. The snail survival and reproduction were observed in Chaohu Lake area(experimental area) and a control area for one year. RESULTS: Snail density was high in two starting points, from where the water in Yangtze River will be directed to Huaihe River. In counties of Wuwei and Hexian, through which the project will be built, the positive rate of anti-schistosome antibody in residents was 22.11% (168/760) and 18.59% (37/199), schistosomiasis prevalence in cattle was 2.42% (9/371) and 0.2% (2/997), respectively. Schistosomiasis was also endemic in Juchao District of Chaohu City. Snails respectively from grassland and hilly area were collected and put in Chaohu Lake for breed and newborn snails were found one year later. During the egg-laying season, the survival rate of snails from grassland in 2 experiment areas and a control area was 11.3%-16.7%, 3.0%-20.8% and 4.7%-14.7% respectively (chi2 = 0.093, 0.760, P > 0.05; chi2 = 0.647, 0, P > 0.05), and that of snails from hilly area was 24.1%-44.4%, 37.8%-67.3% and 86.3%-93.1% respectively (chi2 = 9.575, 5.302, P < 0.05; chi2 = 56.863, 36.218, P < 0.05). There was no significant difference between the experimental area and the control area on the number of eggs in the ovaries of the same type female snails. CONCLUSION: The one-year observation reveals that the construction of the project might result in spread of snails and transmission of schistosomiasis japonica in the relevant areas.