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Electrocatalytic methods are valuable tools for addressing water pollution and scarcity, offering effective pollutant removal and resource recovery. To investigate the current status and future trends of electrocatalysis in wastewater treatment, a detailed analysis of 9417 papers and 4061 patents was conducted using scientometric methods. China emerged as the leading contributor to publications, and collaborations between China and the USA have emerged as the most frequent partnerships. Primary article co-citation clusters focused on oxygen evolution reaction and electrochemical oxidation, transitioning towards advanced oxidation processes ("persulfate activation"), and electrocatalytic reduction processes ("nitrate reduction"). Bifunctional catalysts, theoretical calculations, electrocatalytic combination technologies, and emerging contaminants were identified as current research hotspots. Patent analysis revealed seven types of electrochemical technologies, which were compared using SWOT analysis, highlighting electrochemical oxidation as prominent. The technological evolution presented the pathway of electro-Fenton to combined electrocatalytic technologies with biochemical processes, and finally to coupling with electrocoagulation. Standardized evaluation systems, waste resource utilization, and energy conservation were important directions of innovation in electrocatalytic technologies. Overall, this study provided a reference for researchers to understand the framework of electrocatalysis in wastewater treatment and also shed light on potential avenues for further innovation in the field.
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Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Poluentes Químicos da Água/análise , Eletrodos , Poluentes Ambientais/análise , Oxirredução , Purificação da Água/métodosRESUMO
BACKGROUND: Both infliximab (IFX) and fecal microbiota transplantation (FMT) have shown the efficacy for inflammatory bowel disease (IBD). However, there has no head-to-head study on the cost-value of the such treatments on IBD. This study aimed to compare the medical costs using IFX and the new method of FMT (washed microbiota transplantation [WMT]) in the long-term management for IBD under the current health economic condition in China. METHODS: Patients with IBD who underwent initial WMT via upper gastrointestinal endoscopy, mid-gut tube, or colonic transendoscopic enteral tubing at a university hospital between April 2013 and August 2021 and achieved the long-term sustainment with WMT or WMT combined with mesalazine until August 2022 were recruited in the real-world. The costs and hospitalizations were analyzed among two therapies mentioned above and IFX standard therapy. The charge of WMT was stable in the long term at our center, and the charge of IFX came from virtual statistics publicized by China Healthcare Security. RESULTS: Sixty eligible patients with IBD were included in the study. The long-term costs of patients using WMT monotherapy annually or per hospitalization were lower than those on WMT combined with mesalazine, respectively ( p < 0.001, respectively). The cumulative costs of IFX at the time of 0.52 and 0.85 years exceeded that of the above WMT, respectively ( p < 0.001, respectively). Besides, patients on WMT monotherapy paid 51.1 k CNY annually in the nonsustain phase but cut down the costs by 7.2 k CNY and duration of hospitalization by 5.1 days per hospitalization when reaching the goal of sustainment. CONCLUSION: This study demonstrated that WMT could dramatically reduce the cost and duration of hospitalizations in the long-term sustainment in the current Chinese IBD cohort. Compared with IFX, WMT could be a good way for the patients with IBD achieving long-term sustainment and saving medical costs.
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Doenças Inflamatórias Intestinais , Microbiota , Humanos , Infliximab/uso terapêutico , Infliximab/efeitos adversos , Mesalamina , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/induzido quimicamente , HospitalizaçãoRESUMO
The pyrethroids (PYRs) were extensively used to increase agriculture outputs. However, the cumulative exposures of PYRs would bring about potential risks through food intake. It is an urgent requirement to explore the cumulative exposures on the fruits and vegetables. In this study, a total of 1720 samples incorporating eight primary fruits and vegetables collected around China were investigated to assess the health risk for adults and children from eight PYRs. The relative potency factor (RPF) method was employed to reveal both chronic and acute cumulative exposure. As a result, the hazard index (HI) were 0.004 ~ 0.200% and 11.85 ~ 99.19% for chronic and acute cumulative dietary exposure, respectively. The national wide investigation indicated the cumulative assessments were not hazardous. Besides, the acute intake of pear, grape, and lettuce should be paid on more attention, particularly. This study provides compelling evidence to develop relative policy and regulation to improve the food quality and safety.
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Piretrinas , Verduras , Adulto , Criança , Humanos , Frutas/química , Piretrinas/análise , Exposição Dietética/análise , Medição de Risco , Contaminação de Alimentos/análiseRESUMO
OBJECTIVE: This study examined the dental care utilization and self-preserved dental health of Asian immigrants relative to non-immigrants in Canada. Factors associated with oral health-related disparities between Asian immigrants and other Canadians were further examined. METHODS: We analyzed 37,935 Canadian residents aged 12 years and older in the Canadian Community Health Survey 2012-2014 microdata file. Factors (e.g., demographics, socioeconomic status, lifestyles, dental insurance coverage, and year of immigration) associated with disparities in dental health (e.g., self-perceived teeth health, dental symptoms during past one month, and teeth removed due to decay in past one year) and service utilization (e.g., visiting dentist within the last three years, visiting dentist more than once per year) between Asian immigrants and other Canadians were examined using multi-variable logistic regression models. RESULTS: The frequency of dental care utilization was significantly lower in Asian immigrants than their non-immigrant counterparts. Asian immigrants had lower self-perceived dental health, were less likely to be aware of recent dental symptoms, and more likely to report tooth extractions due to tooth decay. Low education (OR = 0.42), male gender(OR = 1.51), low household income(OR = 1.60), non-diabetes(OR = 1.87), no dental insurance(OR = 0.24), short immigration length (OR = 1.75) may discourage Asian immigrants from dental care utilization. Additionally, a perceived lack of necessity to dentist-visiting was a crucial factor accounting for the disparities in dental care uptake between Asian immigrants and non-immigrants. CONCLUSION: Asian immigrants showed lower dental care utilization and oral health than native-born Canadians.
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Emigrantes e Imigrantes , Humanos , Masculino , Canadá , Nível de Saúde , Cobertura do Seguro , Odontólogos , Seguro OdontológicoRESUMO
The honeysuckle was widely appreciated as tea beverage owing to the biological activities and the unique aroma and flavor. It is in urgent requirement to explore the migration behavior and dietary exposure as the pesticide residues would bring about potential risks through honeysuckle intake. The optimized QuEChERS procedure coupled with the HPLC-MS/MS and GC-MS/MS methods were employed to determine 93 pesticide residues of seven classifications including carbamates, pyrethroid, triazoles, neonicotinoids, organophosphorus, organochlorine, and others for 93 honeysuckle samples from four primary production bases. As a result, 86.02% of the samples were contaminated by at least one pesticide. Unexpectedly, the banned pesticide of carbofuran was also identified. The migration behavior of metolcarb was the highest, whereas thiabendazole contributed less risk to the infusion with relative lower transfer rate. Both the chronic and acute exposure yielded low risk for human health with five high risk pesticides of dichlorvos, cyhalothrin, carbofuran, ethomyl, and pyridaben. Besides, this study provides foundation of dietary exposure risk assessment for honeysuckle and other likewise products.
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Carbofurano , Lonicera , Resíduos de Praguicidas , Praguicidas , Humanos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Lonicera/química , Carbofurano/análise , Exposição Dietética/análise , Praguicidas/análise , Medição de RiscoRESUMO
Management of patients with chronic diseases in rural areas and the use of medications need to be urgently addressed. Therefore, this study aimed to evaluate the efficacy of a family-involved smart medication management system for rural patients with chronic diseases. Between June and August 2021, 82 patients with chronic diseases were selected using convenience sampling from 2 county towns in Hebei Province, China. They were randomly divided into control (41 participants) and experimental (41 participants) groups. The control group was managed using a routine medication management model for chronic diseases. The experimental group was managed using a family-involved smart medication management system, in addition to the control group interventions. The groups were graded using the 8-item Morisky Medication Adherence Scale (MMAS-8), the Self-efficacy for Appropriate Medication Use Scale (SEAMS), the Medication Knowledge Assessment Questionnaire, and the Family Support Scale before the intervention and at 8 and 24 weeks after the intervention. Pre-intervention group differences were not statistically significant. At 8 weeks after the intervention, the control group showed no statistically significant differences in the MMAS-8, SEAMS, and Medication Knowledge Assessment scores pre-and post-intervention. These scores were higher in the experimental group than in the control group, with the post-intervention scores being higher than the pre-intervention scores. The MMAS-8, SEAMS, and Medication Knowledge Assessment scores for the experimental group were higher at 24 weeks than at 8 weeks; these scores were higher in the experimental group than in the control group. The experimental group also had higher family support scores than the control group; these scores were higher pre-intervention than post-intervention. A family-involved smart medication management system can effectively improve medication adherence, self-efficacy for appropriate medication use, medication knowledge assessment scores, and family support for rural middle-aged and older adult patients with chronic diseases.
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Conduta do Tratamento Medicamentoso , População Rural , Pessoa de Meia-Idade , Humanos , Idoso , Adesão à Medicação , Inquéritos e Questionários , Doença CrônicaRESUMO
Volatile organic compounds (VOCs) are toxic to the ecological environment. The emission of VOCs into the atmosphere has already caused attention. However, few studies focus on their regional effects on soil. As a major VOCs source in China, research on the effect of petrochemical industry on the environment is urgent and essential for regional control and industrial layout. This study established national VOCs emission inventory of five petrochemical sub-industries and spatial distribution based on consumption of raw material or products' yield and 28,888 factories. The VOCs emissions showed continuously increasing trend from 2008 to 2019, with cumulative 1.83 × 107 t, wherein these from rapid economic development zones accounted for 66.10%. The detected concentrations of VOCs in various industries combined with meteorological parameters were used in Resistance Model to quantify regional dry deposition. Higher concentrations of 111 VOC species were 238.27, 260.01, 207.54 µg·m-3 from large-scale enterprises for crude oil and natural gas extraction, oil processing, synthetic rubber and resin, leading to higher deposition ratios of 0.81%-0.94%, 0.70%-0.81%, 1.50%-1.75% in rapid economic development zones, respectively. The regional climate condition played a dominant role. Annual VOCs dry deposition amount in rapid economic development zones was calculated to be totally 6.38 × 103 t using obtained deposition ratios and emissions, with 3.21 × 103 t in Bohai Economic Rim (BER), 2.42 × 103 t in Yangtze River Economic Belt (YREB), 748.43 t in Pearl River Delta (PRD). Generally, crude oil and natural gas extraction, oil processing, synthetic rubber and resin contributed 13.09%, 57.77% and 29.14%, respectively. The proportion of synthetic rubber and resin for dry deposition increased by 5.04%-18.81% compared with VOCs emissions in BER and YREB. In contrast, it declined from 45.52% for emission to 29.86% for deposition due to absolute dominance of small-scale enterprises in PRD. Overall, VOCs control from oil processing was significant, especially in BER.
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Poluentes Atmosféricos , Petróleo , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Elastômeros , Monitoramento Ambiental , Gás Natural , Solo , Compostos Orgânicos Voláteis/análiseRESUMO
OBJECTIVE: The main responsibility of caring for patients with glioma is assumed by family caregivers who experience a considerable burden during the care process. This study aimed to investigate the level of caregiver burden and explore its associated factors among family caregivers of patients with glioma. METHODS: We conducted a cross-sectional study among 131 family caregivers of glioma patients from October 2017 to November 2019. We used the following measurement tools: a demographic questionnaire, the Zarit Burden interview (ZBI), the Hamilton anxiety and depression scale, and the family APGAR index. We used multiple linear regression analysis to determine the factors related to caregiver burden. RESULTS: The ZBI score for the family caregivers of glioma patients was 31.29 (SD = 13.54), and most caregivers (71.7%) reported moderate and severe caregiver burdens. Caregivers' daily sleep time and anxiety symptoms and patients' depressive symptoms independently predicted caregiver burden. CONCLUSIONS: Family caregivers of glioma patients experienced a moderate burden. Personalised psychological intervention and sleep health guidance for patients and caregivers should be considered to reduce family caregiver burden and enhance the quality of life and mental health of both patients and their caregivers.
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Cuidadores , Glioma , Sobrecarga do Cuidador , Efeitos Psicossociais da Doença , Estudos Transversais , Glioma/terapia , Humanos , Qualidade de Vida , Inquéritos e QuestionáriosRESUMO
Porcine circovirus type 2 (PCV2) is one of the smallest known animal viruses and is the main pathogen of PCV-associated diseases (PCVAD). Epidemiological surveillance results have shown that the PCV2 infection rate is on the rise in China, thus, PCV2 disease prevention and control has become a huge challenge for the Chinese swine industry. We collected clinical samples from multiple different provinces in China from 2018 to 2020 and found that the positive rate of PCV2 was 53% (3619/6872), identity between the cloned 62 ORF2 genes was 84.4-100% and identity between the cloned 62 ORF2 sequences and reference sequence was 72.9-99.8%. Genetic evolution analysis found that PCV2d accounted for 79% (49/62 samples), PCV2a for 12.9% (8/62 samples), PCV2b for 8% (5/62 samples), and PCV2c and PCV2e genotypes were not found. However, most commercial PCV2 subunit vaccines are based on the PCV2a genotype, and there are very few vaccines based on PCV2b or PCV2d. Therefore, the homologous and heterologous protection ability of PCV2b and PCV2d Cap proteins based on the baculovirus against the PCV2b and PCV2d infections was evaluated, which is expected to design and develop excellent PCV2 protein vaccine candidates. This study found that both PCV2b and PCV2d Cap proteins can increase the level of humoral immunity and cellular immune response in mice. Importantly, both PCV2b and PCV2d cap proteins can provide homologous and heterologous protection against the PCV2b and PCV2d viruses. Overall, this study provides a reference for the prevention and control of PCVAD in mainland China and the development of PCV2 vaccines.
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The spatial distribution uniformity of valuable medicines is the critical quality attribute in the process control of Tongren Niuhuang Qingxin Pills. With the real world sample of the mixed end-point powder of Tongren Niuhuang Qingxin Pills as the research object, hyperspectral imaging technology was used to collect a total of 32 400 data points with a size of 180 pix×180 pix. Spectral angle matching(SAM), classical least squares and mixed tuned matched filtering(MTMF) were used to identify the spatial distribution of rare medicines. MTMF model showed higher identification accuracy, therefore the spatial distribution of the blended intermediates was identified based on the MTMF model. The histogram method was also used to evaluate the spatial distribution uniformity of rare medicines. The results showed that the standard deviation was 4.78, 6.5, 3.48, 1.96, and 3.00 respectively for artificial bezoar, artificial musk, Borneol, Antelope horn and Buffalo horn; the variance was 22.8, 42.3, 12.1, 3.82, and 9.00, and the skewness was 1.26, 1.71, 0.06,-0.86, and 1.04, respectively. The final results showed that the most even blending was achieved in concentrated powder of Borneol, Antelope horn and Buffalo horn, followed by artificial bezoar, and last artificial musk. A visualization method was established for quality attributes of distribution uniformity in blending process of Tongren Niuhuang Qingxin Pills. It could provide evidences of quality control methods in the mixing process of big brand traditional Chinese medicine.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Pós , Controle de QualidadeRESUMO
For the field detection problems of critical quality attribute(CQA) of moisture content in traditional Chinese medicine(TCM) manufacturing process, big brand TCM Tongren Niuhuang Qingxin Pills were used as the carrier, to establish a moisture content NIR field detection model with or without cellophane in real world production with use of near infrared(NIR) spectroscopy combined with stoichiometry. With the moisture content determined by drying method as reference value, the partial least square method(PLS) was used to analyze the correlation between the spectrum and the moisture reference value. Then the spectral pretreatment methods were screened and optimized to further improve the accuracy and stability of the model. The results showed that the best quantitative model was developed by the spectral data pretreatment of standard normal variate(SNV) with the latent variable factor number of 2 and 7 of Tongren Niuhuang Qingxin Pills with or without cellophane samples. The prediction coefficient of determination(R_(pre)~2) and standard deviation of prediction(RMSEP) of the model with cellophane samples were 0.765 7 and 0.157 2%; R_(pre)~2 and RMSEP of the model without cellophane samples were 0.772 2 and 0.207 8%. The NIR quantitative models of moisture content of Tongren Niuhuang Qingxin Pills with and without cellophane both showed good predictive performance to realize the rapid, accurate and non-destructive quantitative analysis of moisture content in such pills, and provide a method for the field quality control of the critical chemical attributes of moisture in the manufacturing of big brand TCM.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Análise dos Mínimos Quadrados , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
Texture sensory attributes are the key items in quality control of Chinese medicinal honeyed pills. The purpose of this study is to develop a quality control method for assessing the texture sensory attributes of Chinese medicinal honeyed pills based on real-world Tongren Niuhuang Qingxin pilular masses and finished products. First, parameters of texture profile analysis(TPA) were optimized through single factor and central composite design(CCD) experiments to establish a detection method for texture sensory attri-butes of Tongren Niuhuang Qingxin Pills. The results showed that the established detection method was stable and reliable, with the optimal parameters set up as follows: deformation percentage of 70%, detection speed at 30 mm·min~(-1), and interval time of 15 s. Furthermore, 540 data points yielded form six texture sensory attributes of pills from 30 batches were subjected to multivariate statistical process control(MSPC) with Hotelling T~2 and squared prediction error(SPE) control charts to establish the quality control method of Tongren Niuhuang Qingxin Pills. This study is expected to provide a reference for improving the quality control system of Chinese medicinal honeyed pills.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Controle de QualidadeRESUMO
Identification of critical quality attribute(CQA) is crucial in quality control of Tongren Niuhuang Qingxin Pills(TRNHQXP). In this study, 661 active components in TRNHQXP were selected by liquid chromatography-mass spectrometry(LC-MS) and network pharmacology based on reported data and TCMSP, BATMAN-TCM, and TCMID databases, as well as mass spectrometry data, and 1 413 targets of the active components were obtained through SwissTargetPrediction. The 152 potential targets obtained from the intersection of predicted targets with 456 stroke targets underwent functional enrichment analysis by Metascape. The 27 Chinese medicinals in TRNHQXP were divided into four sets according to efficacies. Thirty-seven key targets in the blood-activating and stasis-resolving set and 41 in the tonifying set were screened out. On the basis of these potential key targets, 137 potential key CQA of TRNHQXP for stroke were reversely predicted. This study revealed the possible mechanism of TRNHQXP in treating stroke and established a modular identification method for the potential CQA of big brand traditional Chinese medicine(TCM) based on efficacies and chemical properties. Consequently, the CQA of TRNHQXP were identified by this method, which has provided a reference for the following experimental studies of CQA.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Cromatografia Líquida , Controle de QualidadeRESUMO
The chemical properties of characteristic components are significant to the manufacturing quality control of big brand traditional Chinese medicine. In this study, the Huangjing Zanyu Capsules were used as the research carrier to determine the content of five characteristic components including icraiin, emodin, schisandrin A, 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside, and osthole simultaneously by high-performance liquid chromatography(HPLC). The results showed that the chemical properties of five cha-racteristic components had a good linear relationship(r>0.999 9) within the quantitative range; the relative standard deviations(RSD) was 0.11%-2.0% and 0.25%-2.8% respectively for intra-day and inter-day precision; the RSD of repeatability was 1.8%-2.6%; the RSD of stability within 48 hours was 0.19%-2.8%, and the average recovery rate was 95.52%-100.1%, all meeting the requirements of pharmaceutical quantitative analysis. Additionally, the interval estimation method was used to directly reflect the distribution of samples with abnormal chemical properties of characteristic components, and the results showed ten samples were detected beyound the 95% control line of confidence level. Multivariate statistical process control(MSPC) method was used to monitor the abnormal samples of Huangjing Zanyu Capsules collectively, and the results showed that two samples were beyond the 95% control line of Hotelling's T~2 and three samples beyond the 95% control line of squared prediction error(SPE), indicating consistent quality control of Huangjing Zanyu Capsules. In conclusion, the proposed method is not only accurate and efficient but also a compensation for the traditional single-component quality control method, providing a scientific basis for the quality control in manufacturing process of Huangjing Zanyu Capsules. Furthermore, it could also serve as a reference method for the quality control in manufacturing big brand traditional Chinese medicine.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Cápsulas , Cromatografia Líquida de Alta Pressão , Controle de QualidadeRESUMO
With the rapid development of China's economy, volatile organic compounds (VOCs) as the precursor of smog and ozone are of increasing concern, especially in rapidly developing areas. This paper is a systematic analysis of VOCs emissions and distribution trends in 12 typical industrial sectors, garbage and wastewater treatment plants, comprehensive industrial parks, and residential districts in Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta Regions. The results show that pharmacy, rubber producing, as well as paint spraying are the top three industries among the 12 typical industries with the highest average VOCs emission concentrations at 541, 499, and 450 mg·m-3, respectively. By comparison, the average emission concentration of VOCs from the pharmaceutical industry in Yangtze River Delta and Beijing-Tianjin-Hebei Region was, respectively, about 112 and 1.00×103 mg·m-3. The paint spraying industry in the Pearl River Delta region has the highest emission rate with an average concentration of 1.04×103 mg·m-3. The investigation pertaining to the distribution of different VOCs categories indicates that highly toxic aromatics and halogenated hydrocarbons account for the highest emissions in paint spraying and pharmaceutical industries, reaching ratios of 55.99% and 26.57%, respectively. Additionally, among the three major economic zones, the VOCs concentration is the lowest in residential areas and comprehensive industrial parks in the Yangtze River Delta but the highest in the Beijing-Tianjin-Hebei Region, which is consistent with the distribution of industrial emissions in each region. Moreover, the research reveals that VOCs concentration in residential districts experienced a fluctuating reduction from 2002 to 2018. The significant reduction since 2016 suggests that formulated policies, laws and standards, along with the performed techniques have made significant contributions to the control of VOCs.
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In this study, a 2018 anthropogenic volatile organic compounds (VOCs) emission inventory in Hubei Province was conducted using the emission factor method based on activity levels of five sources. The emission characteristics and variation trends of process sources from 2009 to 2018 were further analyzed. Total anthropogenic VOCs emissions were 6.52×105 tons in Hubei Province, accounting for about 6.41% of the country's total omissions. The contributions of fossil combustion sources, process sources, solvent sources, mobile sources, and waste disposal sources were 3.26%, 76.39%, 4.54%, 14.72%, and 1.09%, respectively. Process sources involving 45 sub-categories of nine industries accounted for a significant proportion of VOCs emissions, with Wuhan and Yichang recording the highest VOCs emission levels. The VOCs emissions intensity of each city and state were analyzed based the level of economic activity and territorial area. Tianmen and Shennongjia had higher VOCs emissions per unit of GDP, while Wuhan, Ezhou, and Tianmen had higher VOCs emissions per unit area. Regarding process source contributions, VOCs emissions increased progressively to 2.45×105 tons in 2009 and then stabilized between 2015 and 2017 with maximum emissions of 7.01×105 tons. In 2018, VOCs emissions decreased to 4.98×105 tons. This trend was similar to national anthropogenic emissions. Two industrial sectors, namely chemical raw materials and rubber and plastics, were the main driving force with contributions of 33.85%-51.55% and 7.07%-38.13%, respectively. Among them, the production of chemicals and active pesticide and pharmaceutical ingredients played an important role in contributing to VOCs emissions, while emissions during foam plastics production varied greatly, increasing sharply to more than 2.00×104 tons in 2015-2017. Under the guidance of the relevant national and local policies, emissions from key industries were significantly reduced in Hubei Province.
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In order to understand the sources and distribution characteristics of hexachlorobutadiene (HCBD) in the Yangtze River Delta (YRD), Beijing-Tianjin-Hebei (BTH), and Pearl River Delta (PRD), the emission sources, as well as their distribution in water and soil were analyzed based on the production levels of chlorinated hydrocarbons and wastewater discharge in the three regions. The results showed that the by-products of trichloroethylene (TCE) and tetrachloroethylene (PCE) and wastewater treatment plants were the main sources of HCBD in the three regions. In 2018, the total emissions of HCBD from by-products of TCE and PCE in the three regions were 498.46 t, among which the proportion of by-products of TCE was 66.9%. The HCBD emissions of the three regional industrial and domestic wastewater treatment plants were 628.9 kg and 254.6 kg, respectively. The emissions of HCBD from hydrocarbon chlorination production and wastewater treatment plants in YRD were significantly higher at 497.8 t and 648 kg, respectively, while the emissions from the two sources in BTH were 0.37 t and 125 kg, respectively, and in PRD they were 0.29 t and 110.3 kg, respectively. The average concentrations of HCBD in the natural water of YRD, BTH and PRD were 0.35, 0.25, and 0.64 µg·L-1, respectively, and in the drinking water concentrations were 0.16, 0.09, and 0.04 µg·L-1, respectively. The overall level of HCBD in urban drinking water was relatively low. The concentrations of HCBD in industrial soil were significantly higher than in farmland soil, at 9.3-24.6 ng·g-1 and 0.13-2.67 ng·g-1, respectively. Similar to the situation in water bodies, HCBD pollution in the soil of YRD was the most serious, which was related to the fact that HCBD emissions in YRD were significantly higher than in BTH and PRD.
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Urban resource models increasingly rely on implicit network formulations. Resource consumption behaviours documented in the existing empirical studies are ultimately by-products of the network abstractions underlying these models. Here, we present an analytical formulation and examination of a generic demand-driven network model that accounts for the effectiveness of resource utilization and its implications for policy levers in addressing resource management in cities. We establish simple limiting boundaries to systems' resource effectiveness. These limits are found not to be a function of system size and to be simply determined by the system's average ability to maintain resource quality through its transformation processes. We also show that resource utilization in itself does not enjoy considerable size efficiencies with larger and more diverse systems only offering increased chances of finding matching demand and supply between existing sectors in the system.
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Volatile organic compounds (VOCs) are major contributors to air pollution. Based on the emission characteristics of 99 VOCs that daily measured at 10 am in winter from 15 December 2015 to 17 January 2016 and in summer from 21 July to 25 August 2016 in Beijing, the environmental impact and health risk of VOC were assessed. In the winter polluted days, the secondary organic aerosol formation potential (SOAP) of VOC (199.70 ± 15.05 µg/m3) was significantly higher than that on other days. And aromatics were the primary contributor (98.03%) to the SOAP during the observation period. Additionally, the result of the ozone formation potential (OFP) showed that ethylene contributed the most to OFP in winter (26.00% and 27.64% on the normal and polluted days). In summer, however, acetaldehyde was the primary contributor to OFP (22.00% and 21.61% on the normal and polluted days). Simultaneously, study showed that hazard ratios and lifetime cancer risk values of acrolein, chloroform, benzene, 1,2-dichloroethane, acetaldehyde and 1,3-butadiene exceeded the thresholds established by USEPA, thereby presenting a health risk to the residents. Besides, the ratio of toluene-to-benzene indicated that vehicle exhausts were the main source of VOC pollution in Beijing. The ratio of m-/p-xylene-to-ethylbenzene demonstrated that there were more prominent atmospheric photochemical reactions in summer than that in winter. Finally, according to the potential source contribution function (PSCF) results, compared with local pollution sources, the spread of pollution from long-distance VOCs had a greater impact on Beijing.
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Poluentes Atmosféricos/análise , Ozônio/análise , Compostos Orgânicos Voláteis/análise , Pequim , China , Monitoramento Ambiental , Medição de Risco , Estações do Ano , Emissões de Veículos/análiseRESUMO
A novel strategy of variable selection approach named dynamic backward interval partial least squares-competitive adaptive reweighted sampling (DBiPLS-CARS) was proposed in this study. Near-infrared data sets of three different agro-products, namely corn, crop processing lamina, and plant leaf samples, were collected to investigate the performance of the proposed method. Weak relevant variables were first removed by DBiPLS and a refined selection of the remaining variables was then conducted by CARS. The Monte Carlo uninformative variable elimination (MCUVE) was used as a classical beforehand uninformative variable elimination method for comparison. Results showed that DBiPLS can select informative variables more continuously than MCUVE. Some synergistic variables which may be omitted by MCUVE can be retained by DBiPLS. By contrast, MCUVE can hardly avoid the disturbance of certain weak relevant variables as a result of its calculation based on the full spectrum regression. Therefore, DBiPLS exhibited the advantage of removing the weak relevant variables before CARS, and simultaneously improved the prediction performance of CARS.