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1.
Sci Total Environ ; 897: 165345, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37414190

RESUMO

Considering the ubiquitous occurrences and ecotoxicity of phthalates (PAEs), it is essential to understand their sources, distribution, and associated ecological risks of PAEs in sediments to assess the environmental health of estuaries and support effective management practices. This study provides the first comprehensive dataset on the occurrence, spatial variation, inventory, and potential ecological risk assessment of PAEs in surface sediments of commercially and ecologically significant estuaries in the southeastern United States, Mobile Bay and adjoining eastern Mississippi Sound. Fifteen PAEs were widely detected in the sediments of the study region, with total concentrations varying between 0.02 and 3.37 µg/g. The dominance of low-molecular-weight (LMW) PAEs (DEP, DBP and DiBP) relative to high-molecular-weight (HMW) PAEs (DEHP, DOP, DNP) indicates that residential activities have stronger impacts than industrial activities on PAE distributions. The total PAE concentrations displayed an overall decreasing trend with increasing bottom water salinity, with the maximum concentrations occurring near river mouths. These observations suggest that river inputs were an important pathway by which PAEs were transported to the estuary. Linear regression models identified sediment adsorption (measured by total organic carbon and median grain size) and riverine inputs (measured by bottom water salinity) as significant predictors for the concentrations of LMW and HMW PAEs. Estimated 5-year total inventories of sedimentary PAEs in Mobile Bay and the eastern Mississippi Sound were 13.82 tons and 1.16 tons, respectively. Risk assessment calculations suggest that LMW PAEs posed a medium-to-high risk to sensitive aquatic organisms, and DEHP posed a low or negligible risk to the aquatic organisms. The results of this study provide important information needed for establishing and implementing effective practices for monitoring and regulating plasticizer pollutants in estuaries.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Poluentes Químicos da Água , Plastificantes , Dibutilftalato , Alabama , Ésteres , Medição de Risco , Água , Rios , Poluentes Químicos da Água/análise , China
2.
Ultrasound Med Biol ; 47(8): 2250-2257, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34020846

RESUMO

Our goal was to estimate the agreement between 360° 3-D transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI) of the vaginal invasion in cervical cancer and to discuss the clinical value of 360° 3-D TVUS. A total of 72 patients with untreated cervical cancer were included in the work. The percentage agreement between 2-D TVUS and MRI in assessing vaginal invasion (yes or no) was 77.8% (kappa, 0.400) and that between 360° 3-D TVUS and MRI was 97.2% (kappa, 0.873). The results of 2-D TVUS demonstrated the following agreement with those of MRI: 77.8% for the upper two-thirds of the vagina (kappa, 0.538), 83.3% for the lower third of the vagina (kappa, 0.471). The results of 360° 3-D TVUS demonstrated the following agreement with those of MRI: 95.8% for the upper two-thirds of the vagina (kappa, 0.907), 98.6% for the lower third of the vagina (kappa, 0.961). The results of 360° 3-D TVUS demonstrated good agreement with MRI, which is less costly and more readily available than MRI and should be considered in the pre-treatment work-up for cervical cancer.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Neoplasias do Colo do Útero/patologia , Vagina/patologia , Neoplasias Vaginais/diagnóstico por imagem , Neoplasias Vaginais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Ultrassonografia/métodos
3.
J Hazard Mater ; 397: 122744, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32361139

RESUMO

A two-stage desalination process was developed to achieve zero liquid discharge (ZLD) of flue gas desulfurization (FGD) wastewater by precipitating chloride as Friedel's salt. Influential factors for Friedel's salt precipitation, including dosage, reaction time, concentration of sulfate, were investigate by batch tests. Batch results showed that at calcium to aluminum molar ratio of 3.0, the optimal chloride removal and the highest crystallinity of Friedel's salt were obtained. Sulfate impeded Friedel's salt precipitation by competitive inhibition mechanism, and thus calcium sulfate removal was designed in advance of chloride removal. Batch results and long-term results of bench-scale experiments showed that magnesium and part of sulfate were effectively removed by lime addition in Stage I of the proposed process, and then the remaining sulfate and 48.1 % of chloride were precipitated as ettringite and Friedel's salt in Stage II. The effluent of the two-stage process was alkaline with low turbidity, and had considerable desulfurization capacity. Techno-economic evaluation showed that the two-stage process is technically feasible, economically viable and environmentally friendly technology for ZLD of FGD wastewater.

4.
J Environ Manage ; 235: 161-168, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30682668

RESUMO

Chemical cleaning wastewater (CCW) usually consists of pickling wastewater (PW) and alkaline cleaning wastewater (ACW), and the strategy of separate treatment or combined treatment affects pollutant removal efficiency and cost. In this study, separate and combined treatment of real PW and ACW generated from an on-site cleaning campaign were investigated. A neutralization - fluoride removal - coagulation - oxidation process was constructed for PW and mixed wastewater (MW) treatment, and operational conditions of each process were optimized. The optimal mixing ratio of PW and ACW in the primary neutralization tank was 3:7, which obtained a near neutral pH, efficient chromaticity and turbidity removal and good settling performance. The neutralized MW and PW were both adjusted pH to 9.5 to precipitate metal ions as hydroxides. After fluoride precipitated as CaF2, the fluoride removal rates of MW and PW were both 99.9%, respectively, and polyaluminum chloride was dosed to improve the settleability of CaF2. Then sodium hypochlorite oxidization was employed to remove NH3-N and soluble COD. Techno-economic analysis based on pilot-scale tests showed that separate treatment of PW and ACW obtained better effluent quality than combined treatment. The total cost of combined treatment (37.44 $/m3) was greatly higher than that of separate treatment of PW and ACW (18.20 $/m3). This study proposed a cost-effective strategy for CCW treatment, and suggested that neutralization with acidic or alkaline wastewater should be systematically considered for technical and economic feasibility.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Resíduos Industriais , Oxirredução , Eliminação de Resíduos Líquidos , Águas Residuárias
5.
J Hazard Mater ; 365: 572-580, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30469037

RESUMO

A novel sulfate removal process via ettringite precipitation was developed by dissolving ettringite and recycling Al3+ under low pH condition. Effects of solid to liquid ratios, pH and temperature on ettringite dissolution, Al recovery and transformation of precipitates were investigated by batch experiments. The optimum condition for Al recovery is pH =3.0, suspended solid of 9.8 g/L and temperature below 303 K. Ettringite dissolution consists of two stages, (i) rapid but inconsistent dissolution with the fastest release of sulfate, followed by calcium, and then Al(OH)63-; (ii) slow dissolution of Al(OH)63- core and gypsum precipitation. Dissolution of Al(OH)63- core follows the first-order kinetics with activation energy of 41.18 kJ/mol, while gypsum re-precipitation follows the second-order kinetics with activation energy of 26.36 kJ/mol. Long-term results of pilot-scale systems for treatment of real flue gas desulfurization wastewater showed that the process achieved sulfate removal of 98.3%-99.5% and Al recovery above 98.4%, and converted 98.8% sulfate in ettringite to CaSO4, which resulted in 66.0% of sludge reduction and improved sludge dewaterability. Economic evaluation shows that the process with Al recovery reduces cost of ettringite precipitation by 35.1%, and is highly feasible and cost-effective for industrial application of high-sulfate content wastewater treatment.

6.
Psychol Health Med ; 23(8): 934-951, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29353490

RESUMO

The aim of investigation is to explore the relationship between demands for lung cancer screening (LCS) and the constructs derived from the health belief model (HBM) in Hefei. The study collected data about socio-demographics, health beliefs in and demands for LCS during early June to later July 2015. By constructing a LCS demands HBM constructs, it calculated indices of demands for LCS (DSI) and HBM constructs, which include perceived risk (PR) and seriousness (PS) of the cancers; and perceived effectiveness (PE), benefits (PB) and difficulties (PD) of the screening. It also performed descriptive and multivariate regression analysis of the demands and the HBM constructs. The amount of 823 respondents participated and completed the survey. 6.4% of them had ever undertaken LCS, whereas 60.1% of them expressed willingness to accept the service of LCS if it is free. In multiple regression analysis which used weights in calculating the HBM construct indices, education displayed significant positive associations with DSI (p = .044), and most of HBM constructs indices (PSI, PRI, PBI, and PDI) were statistically significant with DSI (p < .05). HBM-based constructs regarding LCS have important effects on demands for the service, and may provide effective paths to cancer screening promotion.


Assuntos
Atitude Frente a Saúde , Detecção Precoce de Câncer , Neoplasias Pulmonares/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Idoso , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Percepção , Análise de Regressão , Inquéritos e Questionários
7.
Water Sci Technol ; 76(5-6): 1429-1435, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28953469

RESUMO

Flue gas desulfurization (FGD) wastewater treatment by conventional neutralization, chemical precipitation and coagulation process removes most suspended solids and heavy metals, and provides an effluent rich in calcium, alkalinity and chloride, which obstructs its reclamation and reuse but is in favor of phosphorus (P) precipitation. The goals of this study were to investigate feasibility of reusing FGD effluent as a calcium source for P removal from P-rich wastewater. Results revealed that increasing the volumetric ratio between FGD effluent and P-rich wastewater achieved higher pH value and Ca/P ratio, and thus enhanced P removal efficiency to 94.3% at the ratio of 40%. X-ray diffraction and scanning electron microscope analysis of harvested precipitates showed that increasing pH from 8 to 10 induced the conversion of hydroxyapatite to tri-calcium phosphate, and then to whitlockite. This study demonstrated that for reusing FGD effluent for P removal was highly feasible, both technically and economically. This process not only saves the cost of precipitants for P removal, but also provides an economical alternative for current zero liquid discharge technology for FGD wastewater, which requires high energy consumption and capital costs.


Assuntos
Cálcio/química , Fósforo/química , Águas Residuárias/química , Purificação da Água/economia , Precipitação Química , Conservação dos Recursos Naturais/economia , Metais Pesados , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
8.
Medicine (Baltimore) ; 96(27): e7396, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28682893

RESUMO

Caring for prolonged mechanical ventilation (PMV) patients imposes heavy psychological, physical, social, and financial burdens on caregivers. Currently, studies regarding the burden on caregivers of PMV patients are scant; therefore, the present study investigated the burden on caregivers of PMV patients.This cross-sectional study was approved by the Institutional Review Board of Zuoying Armed Forces General Hospital. A survey was conducted among the caregivers of PMV patients who were admitted to a chronic respiratory care ward (RCW) or were receiving home care from June to December 2010. The survey included basic demographic information of PMV patients and their caregivers and the Burden Assessment Scale scores for 4 domains comprising a total of 21 questions (physical burden, n = 5; psychological burden, n = 6; social burden, n = 6; financial burden, n = 4). Statistical analyses were conducted using the t test, 1-way analysis of variance with the Scheffé post hoc test, and the chi-square test, and P < .05 was considered statistically significant.A total of 160 caregivers (age, 50-53 years) were recruited (n = 80 each in the home care and RCW groups), and most of these caregivers were married women. Due to insufficient sleep, physical exhaustion, back pain, and caregiving, home caregivers had significantly higher physical burden levels than RCW caregivers (P < .01).Home caregivers experienced higher physical burden levels than RCW caregivers. Therefore, clinical and professional support must be provided to home caregivers of PMV patients.


Assuntos
Cuidadores , Efeitos Psicossociais da Doença , Respiração Artificial , Idoso , Dor nas Costas , Cuidadores/economia , Cuidadores/psicologia , Estudos Transversais , Família/psicologia , Fadiga , Feminino , Assistência Domiciliar/economia , Assistência Domiciliar/psicologia , Hospitalização/economia , Humanos , Masculino , Pessoa de Meia-Idade , Respiração Artificial/economia , Respiração Artificial/psicologia , Transtornos do Sono-Vigília , Fatores Socioeconômicos , Inquéritos e Questionários , Taiwan
9.
Eur Radiol ; 25(8): 2412-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25744624

RESUMO

OBJECTIVE: The purpose of this study was to determine the feasibility and the value of percutaneous ultrasound-guided subacromial bursography (PUSB) with contrast-enhanced ultrasound (CEUS) for assessment of rotator cuff tears. METHODS: Between January 2012 and September 2014, 2-D US and PUSB were prospectively performed in 135 patients with suspected rotator cuff tears from among 2,169 patients with clinically diagnosed subacromial impingement syndrome. Sixty-three patients who had undergone arthroscopy were included. The PUSB findings were compared with those from 2-D US using the McNemar test, with arthroscopy as a standard. RESULTS: Of a total of 19 full-thickness tears (FTTs), 2-D US correctly diagnosed 12 and PUSB correctly diagnosed 18 (P = 0.031). With regard to partial-thickness tears, 2-D US correctly diagnosed 31 and PUSB 35 of a total of 41 tears (P = 0.375).Accuracy in diagnosing FTTs was 81.0 % for 2-D US and 98.4 % for PUSB. 2-D US and PUSB yielded sensitivity of 63.2 % and 94.7 %, respectively, for full-thickness tears, with specificity of 88.6 % and 100.0 %, respectively. CONCLUSIONS: PUSB is a safe and feasible procedure, with greater sensitivity and specificity than 2D US in diagnosing FTTs As such, PUSB improves the value of ultrasound for assessing rotator cuff pathology. KEY POINTS: • PUSB allows new application of CEUS and offers a new form of bursography. • PUSB appears to facilitate diagnosis of full -thickness rotator cuff tears. • PUSB outlines the rotator cuff tears more clearly than 2-D US.


Assuntos
Microbolhas , Lesões do Manguito Rotador , Síndrome de Colisão do Ombro/diagnóstico por imagem , Adulto , Idoso , Artroscopia/métodos , Bolsa Sinovial/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia , Manguito Rotador/diagnóstico por imagem , Sensibilidade e Especificidade , Traumatismos dos Tendões/diagnóstico , Ultrassonografia de Intervenção/métodos
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