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1.
Sci Total Environ ; 927: 172167, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38580118

RESUMO

The improvement of food security and nutrition has attracted wide attention, and microalgae as the most promising food source are being further explored. This paper comprehensively introduces basic and functional nutrients rich in microalgae by elaborated tables incorporating a wide variety of studies and summarizes factors influencing their accumulation effects. Subsequently, multiple comparisons of nutrients were conducted, indicating that microalgae have a high protein content. Moreover, controllable production costs and environmental friendliness prompt microalgae into the list that contains more promising and reliable future food. However, microalgae and -based foods approved and sold are limited strictly, showing that safety is a key factor affecting dietary consideration. Notably, sensory profiles and ingredient clarity play an important role in improving the acceptance of microalgae-based foods. Finally, based on the bottleneck in the microalgae food industry, suggestions for its future development were discussed.


Assuntos
Microalgas , Inocuidade dos Alimentos , Nutrientes/análise , Valor Nutritivo
2.
Front Endocrinol (Lausanne) ; 14: 1271857, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38089605

RESUMO

Background: Insulin resistance (IR), a risk factor for cardiovascular diseases, has garnered significant attention in scientific research. Several studies have investigated the correlation between IR and coronary artery calcification (CAC), yielding varying results. In light of this, we conducted a systematic review to investigate the association between IR as evaluated by the homeostasis model assessment (HOMA-IR) and CAC. Methods: A comprehensive search was conducted to identify relevant studies in PubMed, Embase, Scopus, and Web of Science databases. In addition, preprint servers such as Research Square, BioRxiv, and MedRxiv were manually searched. The collected data were analyzed using either fixed or random effects models, depending on the heterogeneity observed among the studies. The assessment of the body of evidence was performed using the GRADE approach to determine its quality. Results: The current research incorporated 15 studies with 60,649 subjects. The analysis revealed that a higher category of HOMA-IR was associated with a greater prevalence of CAC in comparison to the lowest HOMA-IR category, with an OR of 1.13 (95% CI: 1.06-1.20, I2 = 29%, P < 0.001). A similar result was reached when HOMA-IR was analyzed as a continuous variable (OR: 1.27, 95% CI: 1.14-1.41, I2 = 54%, P < 0.001). In terms of CAC progression, a pooled analysis of two cohort studies disclosed a significant association between increased HOMA-IR levels and CAC progression, with an OR of 1.44 (95% CI: 1.04-2.01, I2 = 21%, P < 0.05). It is important to note that the strength of the evidence was rated as low for the prevalence of CAC and very low for the progression of CAC. Conclusion: There is evidence to suggest that a relatively high HOMA-IR may be linked with an increased prevalence and progression of CAC.


Assuntos
Doença da Artéria Coronariana , Hiperinsulinismo , Resistência à Insulina , Humanos , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Fatores de Risco , Homeostase
3.
Huan Jing Ke Xue ; 44(6): 3488-3499, 2023 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-37309965

RESUMO

Based on the concentration data of seven heavy metal elements[As, Cd, Cu, Pb, Hg, Ni, and Cr(Ⅵ)] in the surface soil of a typical industrial park in northwest China, the characteristics of heavy metal pollution in the industrial park were analyzed, and the ecological risk and pollution were evaluated using the potential ecological risk index and the index of geo-accumulation. The positive matrix factorization (PMF) model and random forest (RF) model were used for quantitative source analysis, and the emission data of sampling enterprises and empirical data of the source emission component spectrum were combined to identify the characteristic elements and determine the emission source category. The results showed that the heavy metals at all sampling points in the park did not exceed the second-class screening value of construction land in the soil pollution risk control standard for construction land (GB 36600-2018). However, compared with the local soil background values, five elements, excluding As and Cr, were enriched in different degrees, presenting slight pollution and moderate ecological risk (RI=250.04). Cd and Hg were the main risk elements of the park. The results of source analysis showed that the five main sources of pollution were fossil fuel combustion and chemical production sources (33.73%, 9.71%, total source contribution rate of PMF and RF, respectively; the same below), natural sources and waste residue landfill (32.40%, 40.80%), traffic emissions (24.49%, 48.08%), coal burning and non-ferrous metal smelting (5.43%, 0.11%), and electroplating and ore smelting (3.95%, 1.30%). The simulation R2 of the total variable of the two models were above 0.96, indicating that the models could predict heavy metals well. However, considering the actual situation of the number of enterprises in the park and roading density, the main pollution sources of soil heavy metals in the park should be industrial sources, and the simulation results of the PMF model were closer to the actual situation in the park.

4.
J Chem Theory Comput ; 18(6): 3795-3804, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35657167

RESUMO

Cluster expansion (CE) is a powerful theoretical tool to study the configuration-dependent properties of substitutionally disordered systems. Typically, a CE model is built by fitting a few tens or hundreds of target quantities calculated by first-principles approaches. To validate the reliability of the model, a convergence test of the cross-validation (CV) score to the training set size is commonly conducted to verify the sufficiency of the training data. However, such a test only confirms the convergence of the predictive capability of the CE model within the training set, and it is unknown whether the convergence of the CV score would lead to robust thermodynamic simulation results such as order-disorder phase transition temperature Tc. In this work, using carbon defective MoC1-x as a model system and aided by the machine-learning force field technique, a training data pool with about 13000 configurations has been efficiently obtained and used to generate different training sets of the same size randomly. By conducting parallel Monte Carlo simulations with the CE models trained with different randomly selected training sets, the uncertainty in calculated Tc can be evaluated at different training set sizes. It is found that the training set size that is sufficient for the CV score to converge still leads to a significant uncertainty in the predicted Tc and that the latter can be considerably reduced by enlarging the training set to that of a few thousand configurations. This work highlights the importance of using a large training set to build the optimal CE model that can achieve robust statistical modeling results and the facility provided by the machine-learning force field approach to efficiently produce adequate training data.

5.
Comput Intell Neurosci ; 2022: 5792694, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35769271

RESUMO

The development and spread of Internet technology have made it easier to find web servers. People can browse various websites to shop or pay for living expenses, which brings great convenience to life, but as a result, Internet security problems continue to appear. This article is based on a detailed theoretical analysis of mainstream algorithms, making an analysis of web logs which is of great significance and practical value. In addition, through reasoning analysis, technical support is provided for improving the weight factor of the KNN (K-nearest neighbor) algorithm, and the literature research method of the SVM-KNN hybrid algorithm and the KNN classifier is proposed. This paper conducts a detailed theoretical analysis based on the mainstream algorithms that are widely used in the current classification technology and integrates the mainstream classification algorithms in real-life applications and popularization, selecting the support vector machine and KNN calculation method. In the digital economy development model, although China has a large number of netizens, obvious late-comer advantages and institutional advantages as a guarantee, due to the constraints of two key factors, capital and technology, a series of social problems have also arisen. During the transformation of the digital economy, prominent digital security issues, high-risk vulnerabilities, and increasing number of cyber-attacks, along with uneven data quality levels and lagging laws and regulations, have brought many challenges and obstacles.


Assuntos
Inteligência Artificial , Máquina de Vetores de Suporte , Algoritmos , Análise por Conglomerados , Humanos , Internet
6.
Reprod Domest Anim ; 56(9): 1165-1175, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34008236

RESUMO

Reproductive performance is a key factor in determining the profitability of dairy farm, which is affected by many factors such as environment and diseases. Mastitis is a common and important disease, which has caused huge economic losses to the dairy industries worldwide. Mammary gland infection causes immune responses, resulting in the abnormal secretion of cytokines and hormones and abnormal function of the reproductive system such as the ovary, corpus luteum, uterus and embryo. Cows with mastitis have delayed oestrus, decreased pregnancy rate and increased risk of abortion. The adverse effects of mastitis on reproductive performance are affected by many factors, such as occurrence time, pathogen and cow factors. This paper primarily reviews the progress in the effects and mechanisms of mastitis on reproductive performance, with emphasis on maternal transcriptome, genomic analysis, epigenetic modification, microbiota, inflammatory regulation and immune evasion mechanism of mastitis, aiming to provide directions for the prevention and control of mastitis in the future.


Assuntos
Mastite Bovina/complicações , Mastite Bovina/patologia , Reprodução , Aborto Animal , Animais , Bovinos , Indústria de Laticínios/economia , Indústria de Laticínios/estatística & dados numéricos , Epigênese Genética , Feminino , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Gravidez , Taxa de Gravidez , Transcriptoma
7.
Asia Pac J Public Health ; 33(4): 378-387, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33593075

RESUMO

Toilet hygiene is an important preventive measure for infectious diseases, including severe acute respiratory syndrome (SARS) and COVID-19. This study explored public's opinions on improving toilet environment and hygiene practices in Hong Kong. A mixed-method approach was applied. We conducted 4 focus groups plus 3 individual interviews among the Hong Kong Chinese, followed by a questionnaire survey with 300 respondents recruited from various districts. Difference in response distributions between groups with different demographics was tested by Pearson χ2 test. Instead of advocating for advanced toilet facilities, respondents were mostly concerned about basic hygiene issues. Malfunctioning facilities resulting from poor toilet management, such as clogged toilets, stained facilities, and problematic flushing systems, were most cited as barriers to toilet hygiene practices. Three quarters of the survey respondents expressed concerns over worn and poorly maintained toilets, shortage of janitors, and cleansing supplies. However, respondents who were older (P < .001), less educated (P < .001), and had lower income (P = .001) were significantly more likely to find hygiene conditions in public toilets satisfactory. The findings reflected the substandard of the current provisions as a developed city in Asia. Enhanced efforts by the government to maintain basic toilet supplies and facilities is the key to improving public compliance to toilet hygiene practices.


Assuntos
Higiene/normas , Opinião Pública , Banheiros/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/prevenção & controle , Cidades , Controle de Doenças Transmissíveis , Feminino , Grupos Focais , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
8.
Oncol Rep ; 43(2): 405-414, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894341

RESUMO

Living tumors are of great scientific value for clinical medicine and basic research, especially for drug testing. An increasing number of drug tests fail due to the use of imperfect models. The aim of the present study was to develop a novel method combining vitrification­based cryopreservation of tumor biopsies and precision­cut slice cultivation for the assessment of anticancer drug responses. Biological characteristics of rectal cancer liver metastasis biopsies could be retained by vitrification­based cryopreservation. The patient­derived xenograft models were successfully established using both fresh and warmed biopsy tissues. Precision­cut slicing provided a similar three­dimensional architecture and heterogeneity to the original tumor. The positive drug responses in the xenograft model were consistent with those in precision­cut slice cultures in vitro. The present study demonstrated that live tumor biopsies could be preserved using vitrification­based cryopreservation. The warmed tissues developed xenograft tumors, which were also useful for either in vivo or in vitro anticancer drug testing. Precision­cut slices derived from the warmed tissues provided an efficient tool to assess anticancer drug response in vitro.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/patologia , Técnicas de Cultura de Tecidos/métodos , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biópsia , Criopreservação , Feminino , Humanos , Neoplasias Hepáticas/secundário , Masculino , Camundongos , Pessoa de Meia-Idade , Resultado do Tratamento , Vitrificação , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Environ Manage ; 249: 109396, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31472307

RESUMO

Lakes are regarded as copious antibiotic reservoirs because the antibiotics discharged by human activities mostly end up in lakes and further threaten the aqueous ecosystem. Antibiotic contamination in lakes is mostly attributed to wastewater treatment plant effluents, which change the water quality and pose ecological risks. This study investigated the concentration of 10 selected antibiotics in 17 lakes along the middle and lower reaches of the Yangtze River Basin. The correlation between antibiotics and water quality parameters were analyzed. Seven out of the 10 selected antibiotics were detected in almost all the 17 lakes with the highest concentration at 1139.40 ng/L. Sulfamethoxazole (SMZ) and erythromycin (ERY) had relatively higher concentration compared with other antibiotics. Antibiotic detection frequency was approximately 40%-100% in all 17 lakes. Ofloxacin (OFX) and naproxen (NPX) were negatively correlated (p < 0.05) with redox potential, indicating their oxidation potential in freshwater lakes. OFX showed high or medium short-term risks in some of the lakes and low or insignificant long-term risks in the corresponding lakes, respectively. In contrast, sulfadiazine and SMZ exerted low and medium short-term ecological risks and medium and high long-term risks, respectively. Roxithromycin (ROX) showed low short-term risk in seven of the 17 lakes and medium long-term risk in the corresponding lakes. NPX showed insignificant short-term and long-term risks in almost all the 17 lakes. This study fills the gap on antibiotic ecological risk assessment along the Yangtze River Basin and reveal the importance of SMZ control in the research area.


Assuntos
Rios , Poluentes Químicos da Água , Antibacterianos , China , Ecossistema , Monitoramento Ambiental , Humanos , Lagos , Medição de Risco
10.
Biotechnol Lett ; 41(8-9): 915-920, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31256272

RESUMO

OBJECTIVES: To develop an efficient, economical, and low-toxicity method for the extraction of RNA from animal cells to meet a basic requirement of biological research: the isolation of high-quality RNA. RESULTS: Guanidine hydrochloride was used as a lysis buffer and Na-acetate was used as a wash buffer to extract RNA fragments from TM3 Leydig cells and ovarian granulosa cells efficiently. The functionality of the extracted RNA samples was verified through polymerase chain reaction (PCR) and real-time fluorescence quantitative PCR (RT-PCR). PCR results showed that the normal DNA column-based method could guarantee RNA integrity and could be used to amplify gene fragments successfully. RT-PCR analysis showed that the RNA samples isolated through the proposed method could be used to detect the expression levels of steroidogenic acute regulatory protein and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1 mRNA in TM3 Leydig cells under induction by luteinizing hormone. The proposed method could be used to isolate RNA from mammalian cells and provided RNA yields of > 120 ng/5 × 106 cells. This method provided RNA with purities and yields that are sufficient for cDNA synthesis and PCR amplification in gene expression studies. CONCLUSIONS: The proposed RNA extraction method has the advantages of low toxicity, safe handling, and low cost. Isolation can be completed in 20 min. The proposed method can be used to extract RNA from various animal cell samples and is worth promoting.


Assuntos
Células da Granulosa/química , Células Intersticiais do Testículo/química , Biologia Molecular/métodos , RNA/isolamento & purificação , Animais , Feminino , Masculino , Mamíferos , Reação em Cadeia da Polimerase , RNA/genética
11.
J Clin Epidemiol ; 105: 125-135, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30278212

RESUMO

OBJECTIVES: To examine, through a cross-sectional survey, how well safety information was reported among drug systematic reviews predating PRISMA harms checklist and explore factors associated with better reporting. STUDY DESIGN AND SETTING: We searched PubMed to identify all systematic reviews published in the Cochrane Database of Systematic Review or the core clinical journals in 2015, one year before the PRISMA harms checklist was published. We randomly selected, in a 1:1 ratio, Cochrane and non-Cochrane systematic reviews assessing drug effects (including both efficacy and safety). We used the PRISMA harms checklist published in 2016 to assess the quality of reporting of drug safety information. Multivariable linear regression analyses were used to explore the association of six prespecified variables with more complete reporting of PRISMA harms items. RESULTS: We included 120 systematic reviews, including 60 Cochrane and 60 non-Cochrane reviews. Scores on the PRISMA harms checklist (23 items) were low (median 4, [first, third quartile: 2, 6]), with no difference between Cochrane and non-Cochrane reviews (4.5 [2, 7] vs. 4 [2.5, 5]; P = 0.29). Among all eligible reviews, only one item (i.e., state conclusions in coherence with the review findings) was reported adequately (proportion of adherence 81.6%); proportion of reporting for other items ranged from 1.7% to 68.3%. The four essential reporting items from PRISMA harms checklist were also poorly complied (proportion of adherence ranged from 1.7% to 9.2%). Multivariable linear regression analyses found no significant associations between any study characteristic and reporting on the PRISMA harms, likely because of limited variability in scores across studies. CONCLUSIONS: The reporting of safety information was poor both for Cochrane and non-Cochrane drug systematic reviews predating PRISMA harms checklist. The findings suggested a strong need to use the PRISMA harms checklist for reporting safety among drug systematic reviews.


Assuntos
Conduta do Tratamento Medicamentoso , Avaliação de Resultados em Cuidados de Saúde , Segurança do Paciente , Projetos de Pesquisa/normas , Revisões Sistemáticas como Assunto , Lista de Checagem/métodos , Estudos Transversais , Confiabilidade dos Dados , Humanos , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/normas
12.
BMJ Open ; 7(11): e017611, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29101139

RESUMO

OBJECTIVE: China is engaged in promoting community health services (CHS) nationwide. This study examines the public's views towards CHS and their utilisation of community-based and hospital-based outpatient services. DESIGN: A mixed methods study using qualitative interviews and a cross-sectional survey. STUDY SETTING AND PARTICIPANTS: The study was conducted among the public between September 2014 and September 2015 in Zhejiang province, China. Six focus groups and 13 individuals were interviewed. The questionnaire was completed by 1248 respondents (response rate: 83%). PRIMARY OUTCOME MEASURES: Utilisation of community-based and hospital-based outpatient services. RESULTS: Functions of CHS perceived by the public included provision of minor illness management, coordination, drug dispensing, follow-up care and patient education. However, many also showed a distrust in primary care providers' (PCPs) competence for confirming the initial diagnosis and management plan. As coordinators, PCPs' integrity was challenged, and PCPs were thought to be potential 'tuo er' (cunning agents who tried to lead patients to some notorious hospitals to make money). Survey results showed that 800 (64.1%) respondents visited hospital-based clinics and 688 (55.1%) visited CHS at least once in the past year. Compared with the uninsured group, those covered by Urban Resident Medical Insurance (adjusted OR (AOR)=1.95, 95% CI 1.24 to 3.07) and Urban Employee Medical Insurance (AOR=2.59, 95% CI 1.59 to 4.24) were more likely to use hospital-based services. Respondents who had a chronic condition were more likely than their counterparts to use both hospital-based services (AOR=1.72, 95% CI 1.18 to 2.49) and CHS (AOR=1.66, 95% CI 1.19 to 2.32). Income levels were positively associated with the likelihood of visiting hospital-based clinics (AOR=1.67, 95% CI 1.15 to 2.42) but negatively associated with the likelihood of using CHS (AOR=0.68, 95% CI 0.48 to 0.96). CONCLUSIONS: Demand of hospital-based outpatient services is much higher than the community-based outpatient services. Policy reformers need to take further actions to address the public distrust in PCPs to facilitate their gatekeeping role.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , Serviços de Saúde Comunitária/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde , Classe Social , Confiança , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial/economia , China , Serviços de Saúde Comunitária/economia , Estudos Transversais , Feminino , Grupos Focais , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
13.
Health Policy Plan ; 32(9): 1241-1247, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981666

RESUMO

Doctors' profit-oriented practices in public institutions were widespread in China. Two major targets of the healthcare reform launched in 2009 were to curb the profit-making practices in public institutions and to encourage the citizens to use primary care. After 6 years, the status of profit-orientation of public institutions remains unknown. Compared with hospitals, there is no trend of increasing use of primary care. Our study aimed to explore the status of profit-orientation of public institutions and patients' utilization preference. The impacts of guanxi (personal relationship) on patients' utilization of healthcare and doctors' practices were also explored. From September 2014 to September 2015, we conducted focus group and individual interviews, followed by a survey with doctors (n = 1111) in Hangzhou, Zhejiang province. Thematic analysis, independent t-test and Fisher's exact test were conducted to analyse the data. This study found that 36.8% of survey respondents needed to consider making profits for their institutions, especially the hospital specialists. A total of 38.5% and 40.7% thought that their practices led to patients' worries of unnecessary drugs and tests, respectively. Doctors attributed their profit-oriented practices to institutions' agenda setting, poor salary and an organizational bonus system. Their awareness of breaching medical ethics created a guilt feeling and frustration. Nearly 65.0% reported patients' preference for hospital-based care even for minor conditions and 76.2% if the patient was a child. Ineffective gate-keeping mechanism, weak primary care and mistrust in community-based care were major reasons. More specialists than primary care practitioners (41.0 vs 21.5%, P < 0.001) said that patients would use guanxi to gain better services and 64.5% of doctors reported better dedication when patients were somehow connected. In conclusion, profit-orientated practice widely exists in public institutions. Patients generally prefer hospital-based services. Guanxi, which affects both patients' and doctors' practices, is more often used to access hospital-based services.


Assuntos
Economia Hospitalar , Reforma dos Serviços de Saúde/economia , Preferência do Paciente/psicologia , Relações Médico-Paciente , Médicos/economia , Médicos/psicologia , Adulto , China , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Médicos/ética , Padrões de Prática Médica/economia , Atenção Primária à Saúde/economia , Inquéritos e Questionários
14.
Int J Qual Health Care ; 29(6): 867-873, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29025020

RESUMO

OBJECTIVE: Physicians' prescribing patterns may be influenced by how they perceive their patients' expectations of medical care. This study explored doctors' perceptions of patient expectations of medical care. DESIGN: Qualitative interviews and a cross-sectional survey (September 2014-September 2015). SETTING: Primary- and tertiary-care facilities in Zhejiang province, China. PARTICIPANTS: Primary care practitioners (PCPs) and hospital specialists. MAIN OUTCOMES: Perceived patients' expectations. RESULTS: Seven focus groups and 21 individuals were interviewed. Questionnaires were completed by 460 PCPs and 651 specialists (response rate: 78%). About 36.8% of doctors reported generating profit for the facility at which they practiced as a foremost consideration. Participants perceived patients as holding high expectations of clinical performance and use of medical products. Respondents perceived that their patients expected either drug prescriptions (48.2%) or intravenous (IV) therapy (45.2%). Perceived patient expectations of an arrangement of tests and consultation fee refunds if no prescriptions were made were reported by 29.7 and 22.7%, respectively. Doctors reported feeling undervalued and disrespected when patients requested consultation fee refunds. Compared to those who did not report a need for profit-making, doctors who did were significantly more likely to perceive that their patients expected medication-based treatments (AOR = 1.62, P < 0.001), IV therapy (AOR = 1.32, P = 0.037), the arrangement of tests (AOR = 2.06, P < 0.001), and consultation fee refunds when no prescriptions were made (AOR = 1.92, P < 0.001). CONCLUSIONS: Most doctors believed that patients had high expectations. Workplace profit-orientation demonstrated a strong association with doctors' perceptions.


Assuntos
Atitude do Pessoal de Saúde , Preferência do Paciente , Médicos/economia , Padrões de Prática Médica/economia , Administração Intravenosa/economia , Administração Intravenosa/psicologia , Adulto , China , Estudos Transversais , Economia Hospitalar , Feminino , Grupos Focais , Humanos , Masculino , Relações Médico-Paciente , Médicos/psicologia , Médicos de Atenção Primária/economia , Médicos de Atenção Primária/psicologia , Inquéritos e Questionários
15.
Chemosphere ; 150: 152-158, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26901471

RESUMO

Post aerobic digestion of anaerobically digested sludge (ADS) has been extensively applied to the wastewater treatment plants to enhance sludge reduction. However, the degradation of ADS in the post aerobic digester itself is still limited. In this work, an innovative free nitrous acid (HNO2 or FNA)-based pretreatment approach is proposed to improve full-scale ADS degradation in post aerobic digester. The post aerobic digestion was conducted by using an activated sludge to aerobically digest ADS for 4 days. Degradations of the FNA-treated (treated at 1.0 and 2.0 mg N/L for 24 h) and untreated ADSs were then determined and compared. The ADS was degraded by 26% and 32%, respectively, in the 4-day post aerobic digestion period while being pretreated at 1.0 and 2.0 mg HNO2-N/L. In comparison, only 20% of the untreated ADS was degraded. Economic analysis demonstrated that the implementation of FNA pretreatment can be economically favourable or not depending on the sludge transport and disposal cost.


Assuntos
Ácido Nitroso/química , Esgotos/análise , Águas Residuárias/química , Purificação da Água/métodos , Aerobiose , Anaerobiose , Austrália , Reatores Biológicos/microbiologia , Custos e Análise de Custo , Modelos Teóricos , Esgotos/química , Esgotos/microbiologia , Águas Residuárias/análise , Águas Residuárias/microbiologia , Purificação da Água/economia , Purificação da Água/instrumentação
16.
Bioresour Technol ; 182: 267-271, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25704100

RESUMO

Methane production from anaerobic digestion of waste activated sludge (WAS) is limited by the slow hydrolysis rate and/or poor methane potential of WAS. This study presents a novel pre-treatment strategy based on indigenous iron (in WAS) activated peroxidation to enhance methane production from WAS. Pre-treatment of WAS for 30 min at 50mg H2O2/g total solids (dry weight) and pH 2.0 (iron concentration in WAS was 7 mg/g TS) substantially enhanced WAS solubilization. Biochemical methane potential tests demonstrated that methane production was improved by 10% at a digestion time of 16d after incorporating the indigenous iron activated peroxidation pre-treatment. Model-based analysis indicated that indigenous iron activated peroxidation pre-treatment improved the methane potential by 13%, whereas the hydrolysis rate was not significantly affected. The economic analysis showed that the proposed pre-treatment method can save the cost by $112,000 per year in a treatment plant with a population equivalent of 300,000.


Assuntos
Ferro/química , Metano/biossíntese , Esgotos , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Fenômenos Bioquímicos , Biocombustíveis/economia , Custos e Análise de Custo , Peróxido de Hidrogênio/química , Hidrólise , Modelos Teóricos , Eliminação de Resíduos Líquidos/economia
17.
Sci Rep ; 5: 7516, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25559367

RESUMO

Improvement of sludge dewaterability is important for reducing the total costs for the treatment and disposal of sludge in wastewater treatment plants. In this study, we investigate the use of hydrogen peroxide as an oxidizing reagent for the conditioning of waste activated sludge. Significant improvement to sludge dewaterability was attained after the addition of hydrogen peroxide at 30 mg/g TS and 28 mg/g TS under acidic conditions (pH = 3.0), with the highest reduction of capillary suction time being 68% and 56%, respectively, for sludge containing an iron concentration of 56 mg Fe/g TS and 25 mg Fe/g TS, respectively. The observations were due to Fenton reactions between the iron contained in sludge (indigenous iron) and hydrogen peroxide. For the sludge with an insufficient level of indigenous iron, the addition of ferrous chloride was found to be able to improve the sludge dewaterability. The results firstly indicated that indigenous iron can be utilized similarly as the externally supplied iron salt to improve sludge dewaterability through catalyzing the Fenton reactions.


Assuntos
Compostos Ferrosos/química , Esgotos/química , Catálise , Peróxido de Hidrogênio/química , Ferro/química , Oxirredução , Eliminação de Resíduos Líquidos/economia , Água/química
18.
Bioresour Technol ; 177: 194-203, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25490102

RESUMO

An ozone/ultrasound lysis-cryptic growth technology combining a continuous flow anaerobic-anoxic-microaerobic-aerobic (AAMA+O3/US) system was investigated. Techno-economic evaluation and sludge lyses return ratio (r) optimization of this AAMA+O3/US system were systematically and comprehensively discussed. Economic assessment demonstrated that this AAMA+O3/US system with r of 30% (AAMA+O3/US2# system) was more economically feasible that can give a 14.04% saving of costs. In addition to economic benefits, a 55.08% reduction in sludge production, and respective 21.17% and 5.45% increases in TN and TP removal efficiencies were observed in this AAMA+O3/US2# system. Considering the process performances and economic benefits, r of 30% in AAMA+O3/US2# system was recommended. Excitation-emission matrix and Fourier transform infrared spectra analyses also proved that less refractory soluble microbial products were generated from AAMA+O3/US2# system. Improvement in 2,3,5-triphenyltetrazolium chloride electron transport system (TTC-ETS) activity in AAMA+O3/US2# further indicated that a lower sludge lyses return ratio stimulated the microbial activity.


Assuntos
Compostos Orgânicos/isolamento & purificação , Ozônio/química , Esgotos/química , Ultrassom/métodos , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Aerobiose , Compostos de Amônio/isolamento & purificação , Anaerobiose , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Transporte de Elétrons , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Sais de Tetrazólio/química , Fatores de Tempo
19.
Bioresour Technol ; 174: 103-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25463788

RESUMO

Improvement of sludge dewaterability is crucial for reducing the costs of sludge disposal in wastewater treatment plants. This study presents a novel method based on combined conditioning with zero-valent iron (ZVI) and hydrogen peroxide (HP) at pH 2.0 to improve dewaterability of a full-scale waste activated sludge (WAS). The combination of ZVI (0-750mg/L) and HP (0-750mg/L) at pH 2.0 substantially improved the WAS dewaterability due to Fenton-like reactions. The highest improvement in WAS dewaterability was attained at 500mg ZVI/L and 250mg HP/L, when the capillary suction time of the WAS was reduced by approximately 50%. Particle size distribution indicated that the sludge flocs were decomposed after conditioning. Economic analysis showed that combined conditioning with ZVI and HP was a more economically favorable method for improving WAS dewaterability than the classical Fenton reaction based method initiated by ferrous salts and HP.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Esgotos/química , Resíduos/análise , Purificação da Água/métodos , Água/química , Técnicas de Cultura Celular por Lotes , Floculação , Purificação da Água/economia
20.
Soc Sci Med ; 117: 134-41, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25063969

RESUMO

Like many other countries China is undergoing major health system reforms, with the aim of providing universal health coverage, and addressing problems of low efficiency and inequity. The first phase of the reforms has focused on strengthening primary care and improving health insurance coverage and benefits. The aim of the study was to explore the impacts of these reforms on healthworkers and service-users at township level, which has been the major target of the first phase of the reforms. From January to March 2013 we interviewed eight health officials, 80 township healthworkers and 80 service-users in eight counties in Zhejiang and Yunnan provinces, representing rich and poor provinces respectively. Thematic analysis identified key themes around the impacts of the health reforms. We found that some elements of the reforms may actually be undermining primary care. While the new health insurance system was popular among service-users, it was criticised for contributing to fast-growing medical costs, and for an imbalance of benefits between outpatient and inpatient services. Salary reform has guaranteed healthworkers' income, but greatly reduced their incentives. The essential drug list removed perverse incentives to overprescribe, but led to falls in income for healthworkers, and loss of autonomy for doctors. Serious problems with drug procurement also emerged. The unintended consequences have included a brain drain of experienced healthworkers from township hospitals, and patients have flowed to county hospitals at greater cost. In conclusion, in the short term resources must be found to ensure rural healthworkers feel appropriately remunerated and have more clinical autonomy, measures for containment of the medical costs must be taken, and drug procurement must show increased transparency and accountability. More importantly the study shows that all countries undergoing health reforms should elicit the views of stakeholders, including service-users, to avoid and address unintended consequences.


Assuntos
Atitude do Pessoal de Saúde , Reforma dos Serviços de Saúde , Atenção Primária à Saúde/estatística & dados numéricos , Serviços de Saúde Rural , Adulto , Atitude Frente a Saúde , China , Atenção à Saúde/economia , Feminino , Humanos , Seguro Saúde/economia , Entrevistas como Assunto , Masculino , Motivação , Serviços de Saúde Rural/economia , Serviços de Saúde Rural/estatística & dados numéricos
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