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1.
Clin Chem Lab Med ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38877871

RESUMO

Venous blood collection systems (VBCSs) are combinations of in-vitro diagnostics and medical devices, usually available as integrated set. However, purchasing and using a combination of devices from different sets is considered by clinical laboratories as an option to achieve specific sampling tasks or reduce costs. This systematic review aimed to retrieve available evidence regarding safety, efficacy, and economic aspects of VBCSs, focusing on differences between integrated and combined systems. The literature review was carried out in PubMed. Cited documents and resources made available by scientific organisations were also screened. Extracted evidence was clustered according to Quality/Efficacy/Performance, Safety, and Costs/Procurement domains and discussed in the current European regulatory framework. Twenty documents published between 2010 and 2021 were included. There was no evidence to suggest equivalence between combined and integrated VBCSs in terms of safety and efficacy. Scientific society's consensus documents and product standards report that combined VBCS can impact operators' and patients' safety. Analytical performances and overall efficacy of combined VBCSs are not guaranteed without whole system validation and verification. EU regulatory framework clearly allocates responsibilities for the validation and verification of an integrated VBCS, but not for combined VBCSs, lacking information about the management of product nonconformities and post-market surveillance. Laboratory validation of combined VBCS demands risk-benefit and cost-benefit analyses, a non-negligible organisational and economic burden, and investment in knowledge acquisition. Implications in terms of laboratory responsibility and legal liability should be part of a comprehensive assessment of safety, efficacy, and cost carried out during device procurement.

2.
J Environ Manage ; 330: 117129, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584456

RESUMO

The effectiveness of a three-stage pilot approach using adsorption (AD), electrocoagulation (EC) and biological (BIO) processes for the treatment of raw sanitary landfill leachate (SLL) was investigated. SLL is loaded with hazardous substances such as organic load and heavy metals with high ammonium nitrogen (NH4+-N) concentrations and is also produced in large quantities, causing serious risks to both living organisms and the environment. In this study, column adsorption experiments were initially performed to examine the removal of toxic NH4+-N using different initial NH4+-N concentrations and recirculation flow rates. The adsorption process was then examined as a pre-treatment step in two sequential treatment scenarios, i.e., AD-EC-BIO and AD-BIO-EC, to determine which achieved the highest removal of pollutants and leachate toxic potential, thus ensuring the biosafety of these processes during the release of the respective effluents into surface waters. The overall removal efficiencies of NH4+-N, color, dissolved chemical oxygen demand (d-COD), manganese (Mn), nickel (Ni), zinc (Zn) and iron (Fe) achieved after the application of the AD-EC-BIO system were 95.5 ± 0.1%, 98.8 ± 0.1%, 85.7 ± 0.8%, 100 ± 0.1%, 71.4 ± 1.7%, 63.8 ± 1.9% and 94.2 ± 0.2%, respectively, while the values for the AD-BIO-EC system were 98.5 ± 0.2%, 98.7 ± 0.1%, 85.7 ± 0.4%, 98.9 ± 1.2%, 67.7 ± 1.7%, 76.1 ± 1.6% and 94.8 ± 0.1%, respectively. In accordance with the latter, the assessment of leachate toxic potential using a Thamnocephalus platyurus bioassay revealed that the AD-EC-BIO system could be considered a promising treatment strategy for the purification of raw SLL.


Assuntos
Compostos de Amônio , Fenômenos Biológicos , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Adsorção , Eletrocoagulação , Análise da Demanda Biológica de Oxigênio
3.
Molecules ; 28(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37630339

RESUMO

The issue of food fraud has become a significant global concern as it affects both the quality and safety of food products, ultimately resulting in the loss of customer trust and brand loyalty. To address this problem, we have developed an innovative approach that can tackle various types of food fraud, including adulteration, substitution, and dilution. Our methodology utilizes an integrated system that combines laser-induced breakdown spectroscopy (LIBS) and Raman spectroscopy. Although both techniques emerged as valuable tools for food analysis, they have until now been used separately, and their combined potential in food fraud has not been thoroughly tested. The aim of our study was to demonstrate the potential benefits of integrating Raman and LIBS modalities in a portable system for improved product classification and subsequent authentication. In pursuit of this objective, we designed and tested a compact, hybrid Raman/LIBS system, which exhibited distinct advantages over the individual modalities. Our findings illustrate that the combination of these two modalities can achieve higher accuracy in product classification, leading to more effective and reliable product authentication. Overall, our research highlights the potential of hybrid systems for practical applications in a variety of industries. The integration and design were mainly focused on the detection and characterization of both elemental and molecular elements in various food products. Two different sets of solid food samples (sixteen Alpine-style cheeses and seven brands of Arabica coffee beans) were chosen for the authentication analysis. Class detection and classification were accomplished through the use of multivariate feature selection and machine-learning procedures. The accuracy of classification was observed to improve by approximately 10% when utilizing the hybrid Raman/LIBS spectra, as opposed to the analysis of spectra from the individual methods. This clearly demonstrates that the hybrid system can significantly improve food authentication accuracy while maintaining the portability of the combined system. Thus, the successful implementation of a hybrid Raman-LIBS technique is expected to contribute to the development of novel portable devices for food authentication in food as well as other various industries.


Assuntos
Queijo , Análise Espectral Raman , Contaminação de Medicamentos , Fraude , Indústrias
4.
Biotechnol J ; 19(4): e2300723, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622797

RESUMO

Polyurethane (PU) is a complex polymer synthesized from polyols and isocyanates. It contains urethane bonds that resist hydrolysis, which decreases the efficiency of biodegradation. In this study, we first expressed the amidase GatA250, and then, assessed the enzymatic characterization of GatA250 and its efficiency in degrading the polyester-PU. GatA250 degraded self-synthesized thermoplastic PU film and postconsumption foam with degradation efficiency of 8.17% and 4.29%, respectively. During the degradation, the film released 14.8 µm 4,4'-methylenedianiline (MDA), but 1,4-butanediol (BDO) and adipic acid (AA) were not released. Our findings indicated that GatA250 only cleaved urethane bonds in PU, and the degradation efficiency was extremely low. Hence, we introduced the cutinase LCC, which possesses hydrolytic activity on the ester bonds in PU, and then used both enzymes simultaneously to degrade the polyester-PU. The combined system (LCC-GatA250) had higher degradation efficiency for the degradation of PU film (42.2%) and foam (13.94%). The combined system also showed a 1.80 time increase in the production of the monomer MDA, and a 1.23 and 3.62 times increase in the production of AA and BDO, respectively, compared to their production recorded after treatment with only GatA250 or LCC. This study provides valuable insights into PU pollution control and also proposes applicable solutions to manage PU wastes through bio-recycling.


Assuntos
Compostos de Anilina , Hidrolases de Éster Carboxílico , Poliésteres , Poliuretanos , Poliésteres/química , Amidoidrolases
5.
Plants (Basel) ; 13(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38592888

RESUMO

Grassland covers approximately 17.4% of Europe's land area, stores about 20% of the world's soil carbon and has the potential to sequester carbon. With the help of sustainable management systems, grasslands could reduce greenhouse gases and act as a terrestrial sink for atmospheric CO2. In this study, we will investigate the effect of grassland management (cutting, grazing, and a combination of the two) and soil depth (0-10, 10-20, 20-30 cm) on the physical (volumetric water content-VWC, bulk density-BD, porosity-POR, mass consisting of coarse fragments-FC) and chemical properties of soil (organic carbon-SOC, inorganic carbon-SIC, total carbon-STC, total nitrogen-STN, organic matter-SOM, C/N ratio, pH) in Central European lowlands. The management system affected BD, SOC and STN and tended to affect VWC and STC in the first soil depth only. Grazing and the combined system stored greater amounts of STN, SOC and STC and had higher BDs at the surface (0-10 cm) compared to the cutting system. Most soil properties were influenced by soil depth, with C/N ratio and BD increasing and SOC, STC, STN, SOM, VWC and POR decreasing with depth. Our study highlights an opportunity for grassland users to improve soil quality, reduce fossil fuel usage and improve animal welfare through their management systems and argues that systems such as grazing and the combined system should be promoted to mitigate climate change.

6.
Ann Agric Environ Med ; 30(3): 455-461, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37772520

RESUMO

INTRODUCTION AND OBJECTIVE: The identification and understanding of interactions between contaminants present in sediments from stormwater and combined sewer systems is a prerequisite for their proper management, and provides a basis for developing effective strategies to minimize their negative impact on humans and the environment. The studypresents the method described in PN-EN 12457-2:2006 as a possible technique for studying the mobility of heavy metals in sediments from stormwater and combined sewer systems. MATERIAL AND METHODS: The presented PN-EN 12457-2:2006 method is a relatively simple technique for preparing extracts for the determination of heavy metals in sediments from stormwater and combined sewer systems, consisting of one-step leaching, which is quick to perform. In addition, it allows determination of the characteristics of the samples to be analyzed, and indicates procedures and tests for evaluating hazardous substances released from solid waste. RESULTS: The results of the concentrations of leached heavy metals: chromium, copper, nickel, lead and zinc, obtained in the study, corresponded to the concentrations of the exchange fraction of sludge when using the recommended method with sequential extraction (Student's t-test, p=0.263). In the literature review conducted, no papers were found on the application of the leaching method to prepare extracts for the determination of heavy metals in sediments from stormwater and combined sewer systems. CONCLUSIONS: The PN-EN 12457-2:2006 method is capable of providing important data on the potential risks to humans and the environment from the presence of contaminants in sewage sludge.

7.
Curr Drug Deliv ; 20(7): 943-950, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35611774

RESUMO

BACKGROUND: The combinatorial use of anticancer drugs, dual or multiple, with a specific nanocarrier is one of the most promising attempts in drug delivery. The current work reports potassium contained graphene oxide (K-GO) as a nanocarrier in the drug delivery system of two anticancer drugs, gefitinib (GEF) and camptothecin (CPT), simultaneously. METHODS: To characterize K-GO, K-GO-related single and combined drug systems, different techniques have been performed and studied using the following spectroscopic tools, such as Thermo Gravimetric Analysis (TGA 4000), UV-visible spectroscopy, Raman spectroscopy, and Transmission electron microscopy (TEM). The in vitro cytotoxicity tests of K-GO, single drug system, and the combined drug system were also performed in the human breast cancer MDA-MB-231 cells. RESULTS: The release profile of the dual drug conjugates grafted onto the surface of K-GO was found to be up to 38% in PBS solution over 72 hours. The percentage of MDA-MB-231 cell viability was about 18% when treated with K-GO-GEF-CPT combined system; for K-GO, K-GO-GEF, and K-GO-CPT, the cell viability was 79%, 31%, and 32%, respectively. CONCLUSION: We studied the loading, release, and delivery of two anticancer drugs onto the fluorescent nanocarrier. Features, such as superb aqueous solubility, excellent biocompatibility, richness in potassium, and fluorescent nature, which can monitor the delivery of drugs, make them a promising nanocarrier for single or multiple drug delivery. Furthermore, our novel findings revealed that the loading capacity and cytotoxicity of the combined drug-loaded system are superior to the capacity of the individual drug system for human breast cancer cells.


Assuntos
Antineoplásicos , Neoplasias da Mama , Grafite , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/química , Gefitinibe , Portadores de Fármacos/química
8.
Sci Total Environ ; 868: 161632, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36657675

RESUMO

Water resources of many rural areas are usually lakes or reservoirs, which can be easily affected by run-off, non-point source pollution and are often of poorer quality compared with urban water sources. Drinking water supply in remote rural areas usually suffers from various challenges, such as the high cost of construction and maintenance of centralized drinking water treatment plants and pipe networks, due to the dispersed nature of villages, which are often located in varied and complex topographies. In this study, a combined process comprising biological aerated filter (BAF) combined with ultrafiltration was developed to treat polluted reservoir water. Organic matter indexes, turbidity, and chroma were used as indicators for the evaluation of the system performance. In a long-term experiment lasting 260 days, the combined process was tested under different values of critical operational parameters, including filler types and empty bed contact time (EBCT). Furthermore, the microbial communities in different BAF reactors were carefully evaluated at different times, finding that microorganisms with specific functions were enriched in the various BAF reactors. The combined process reached 85.5 % removal rate of DOC with an EBCT of 45 min and using granule active carbon (GAC) as filler. Most of the effluents of BAF reactors met the requirements for drinking water in China. The combined system showed practical potential for polluted water treatment in some rural areas.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Ultrafiltração , Abastecimento de Água , Carvão Vegetal , Poluentes Químicos da Água/análise , Filtração
9.
Environ Sci Pollut Res Int ; 30(1): 1622-1639, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35921006

RESUMO

In this study, different K-nearest neighbors (KNN), support vector regression (SVR), decision tree (DT), and random forest (RF) algorithms integrated with the Bayesian optimization algorithm (BOP) have been applied as novel hybrid modeling/optimization tools to predict the total nitrogen in treated wastewater of Southern Tehran Wastewater Treatment Plant (STWWTP). In order to enhance the outcomes of hybrid models, the chosen sub-models (the best and least correlated hybrid models) were used to generate voting average and stacked regression ensemble models. Throughout the preprocessing step, two alternative scenarios were used to handle missing values from the samples, including elimination versus estimation via linear interpolation. The results of this research demonstrated that ensemble models were better than individual hybrid models, although not all ensemble models were superior to single models. The results also revealed that the stacking regression ensemble model using KNN-BOP and SVR-BOP as sub-models was the most superior model among the developed models, with the coefficient of determination (R2) = 0.640, root mean squared error (RMSE) = 2.378, and mean absolute error (MAE) = 1.838 on the test data. The best hybrid ensemble model that can accurately predict the concentration of total nitrogen (TN) in the effluent can give people a heads-up about water pollution caused by eutrophication before it gets bad.


Assuntos
Esgotos , Purificação da Água , Humanos , Nitrogênio , Teorema de Bayes , Irã (Geográfico) , Purificação da Água/métodos
10.
Water Environ Res ; 94(12): e10815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36514808

RESUMO

In this study, a combined system with simultaneous nitrification, denitrification, and phosphorus removal was operated in continuous low oxygen aeration mode, and the effect of lower oxygen aeration (dissolved oxygen [DO] 0.5-1.5 mg/L) on its performance was examined. The combined system consisted of sludge and high-efficiency biological packing and was operated using four carbon/nitrogen ratios (C/N) with being 10:1, 8:1, 6:1, 10:1. Experimental results showed that the combined system could perform an efficient nitrogen and phosphorus removal under low DO and C/N ratio of 8:1 condition, and removal efficiencies of chemical oxygen demand (COD), NH4 + -N, and PO4 3- -P were 80.01%, 99.03%, and 89.51%, respectively. High-throughput analysis indicated that the functional species of denitrifying bacteria, including Ferruginibacter Azospira, Comamonas, Bacilli, Hyphomicrobium, Thauera, and Comamonadaceae, were important participants in biological nutrient removal. Meanwhile, Acinetobacter was enriched in the combined system, which contributed to phosphorus removal. PRACTITIONER POINTS: A combined system was operated firstly under continuous low oxygen condition. The lower dissolved oxygen (DO) of the combined system was maintained at 0.50-1.5 mg/L level. The combined system could realize simultaneous phosphorus and nitrogen removal under C/N ratio of 8:1. Several functional bacteria were enriched in the coupled systems.


Assuntos
Nitrogênio , Fósforo , Humanos , Desnitrificação , Carbono , Eliminação de Resíduos Líquidos/métodos , Oxigênio , Reatores Biológicos/microbiologia , Nitrificação , Esgotos/microbiologia , Bactérias
11.
Environ Sci Pollut Res Int ; 26(22): 22756-22771, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172433

RESUMO

Giardia and Cryptosporidium have caused numerous outbreaks of diarrhea as a result of the ingestion of water contaminated with sewage. In Brazil, the efficiency of Giardia and Cryptosporidium removal by combined fixed-film systems has rarely been studied. The aims of the present study were therefore to verify the removal efficiency of Giardia and Cryptosporidium by a combined system (anaerobic/anoxic filter and aerated submerged biofilter) and to perform the genetic characterization of these parasites. The (oo)cysts were detected by centrifuge concentration and membrane filtration from raw sewage, effluents, adhered biomass, and sludge samples. Immunofluorescence assay and differential interference contrast microscopy were used for the visualization of the (oo)cysts. Nested PCR was applied to confirm Giardia and Cryptosporidium. Giardia and Cryptosporidium were detected in 27% and 5.5% of the 144 analyzed samples of raw sewage and effluents, respectively. A total of 33,000 cysts/L were recovered in the adhered biomass samples (n = 25) from different points of the aerated submerged biofilter, while 6000 oocysts/L were registered in a single point. An average of 11,800 cysts/L were found in the sludge samples (n = 5). The combined system exhibited a removal efficiency of Giardia cysts of 1.8 ± 1.0 log removal. The C and BIV assemblages of Giardia were identified in the raw sewage while AII was found in the treated effluent sample. It was not possible to calculate the removal efficiency of Cryptosporidium oocysts by the combined system. The combined system exhibited some potential as a suitable treatment for the removal of parasites from sewage.


Assuntos
Cryptosporidium , Giardia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/parasitologia , Animais , Brasil , Giardíase/epidemiologia , Hospitais , Oocistos , Esgotos/parasitologia
12.
Ultrasound Med Biol ; 44(3): 734-742, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29311005

RESUMO

We analyzed the performance of a mammographically configured, automated breast ultrasound (McABUS) scanner combined with a digital breast tomosynthesis (DBT) system. The GE Invenia ultrasound system was modified for integration with GE DBT systems. Ultrasound and DBT imaging were performed in the same mammographic compression. Our small preliminary study included 13 cases, six of whom had contained invasive cancers. From analysis of these cases, current limitations and corresponding potential improvements of the system were determined. A registration analysis was performed to compare the ease of McABUS to DBT registration for this system with that of two systems designed previously. It was observed that in comparison to data from an earlier study, the McABUS-to-DBT registration alignment errors for both this system and a previously built combined system were smaller than those for a previously built standalone McABUS system.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/instrumentação , Mamografia/métodos , Imagem Multimodal/métodos , Ultrassonografia Mamária/instrumentação , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Chemosphere ; 208: 793-799, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29906753

RESUMO

To exploit the advantages of less electron donor consumptions in partial-denitrification (denitratation, NO3- → NO2-) as well as less sludge production in autotrophic denitrification (AD) and anammox, a novel biological nitrogen removal (BNR) process through combined anammox and thiosulfate-driven denitratation was proposed here. In this study, the ratio of S2O32--S/NO3--N and pH are confirmed to be two key factors affecting the thiosulfate-driven denitratation activity and nitrite accumulation. Simultaneous high denitratation activity and substantial nitrite accumulation were observed at initial S2O32--S/NO3--N ratio of 1.5:1 and pH of 8.0. The optimal pH for the anammox reaction is determined to be 8.0. A sequential batch reactor (SBR) and an up-flow anaerobic sludge blanket (UASB) reactor were established to proceed the anammox and the high-rate thiosulfate-driven denitratation, respectively. Under the ambient temperature of 35 °C, the total nitrogen removal efficiency and capacity are 73% and 0.35 kg N/day/m3 in the anammox-SBR. At HRT of 30 min, the NO3- removal efficiency could achieve above 90% with the nitrate-to-nitrite transformation ratio of 0.8, implying the great potential to apply the thiosulfate-driven denitratation & anammox system for BNR with minimal sludge production. Without the occurrence of denitritation (NO2- → N2O → N2), theoretically no N2O could be emitted from this BNR system. This study could shed light on how to operate a high rate BNR system targeting to electron donor and energy savings as well as biowastes minimization and greenhouse gas reductions.


Assuntos
Desnitrificação , Nitrogênio/química , Esgotos/química , Tiossulfatos/química , Anaerobiose , Reatores Biológicos , Estudos de Viabilidade , Nitratos/química , Nitritos/química , Oxirredução
14.
Huan Jing Ke Xue ; 38(6): 2419-2428, 2017 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965361

RESUMO

As an effective technology for wastewater treatment, bio-filter has been widely used. Nevertheless, there is still a lack of systematic report on purification efficiency and influencing factors of combined bio-filters. To this end, a novel combined system that consisted of aerated vertical-flow filter (AVF) followed by baffled horizontal-flow filter (BHF) was designed. After setting a series of hydraulic loading rates (131, 94 and 60 mm·d-1) and diversion ratios (8:2、6:4、4:6), we comprehensively assessed the impact of running condition adjustment on treatment performance by multiple statistical analyses. The results showed that, the average removal rates of organic matter, ammonia nitrogen and dissolved nitrogen in AVF were all above 80%, while the average removal rates of ammonia nitrogen, total nitrogen and dissolved nitrogen in BHF were all below 40%. Different running conditions had a significant (P<0.05) impact on treatment performance. Meanwhile, there were significant differences in purification efficiency between the two different kinds of filters. Oxidative degradation was one of the main ways to remove organic matter in the two kinds of filters. There were obvious nitrification and denitrification processes within the two kinds of filters. Nitrification followed by denitrification was the main way to remove total nitrogen since ammonium occupied the most portion of total nitrogen in the synthetic wastewater. Meanwhile, the intensity of nitrification and denitrification in AVF was obviously higher than that in BHF. Phosphorus removal was mainly controlled by hydraulic loading rate, temperature, dissolved oxygen, organic matter, etc. This might indicate that microbial absorption was one of the main ways to remove phosphorus for the two filters. Compared to the sole AVF, the removal of total organic matter and total phosphorus in the combined system was increased by 4.4% and 23.2%, respectively, but the removal of total nitrogen was reduced by 12.1%. Reducing the diversion ratio was helpful to improve the denitrification intensity in BHF. However, due to the introduction of excessive ammonia from the raw wastewater, as well as the limited nitrification capacity in BHF, the removal rate of total nitrogen for the combined system was decreased. Therefore, according to the composition of treated raw wastewater, the control of appropriate diversion ratio, residence time and redox conditions inside the filter bed was the key to enhance the overall performance of the combined system.


Assuntos
Aquicultura , Desnitrificação , Nitrificação , Eliminação de Resíduos Líquidos , Purificação da Água , Amônia/isolamento & purificação , Reatores Biológicos , Filtração , Nitrogênio/isolamento & purificação , Águas Residuárias
15.
J Hazard Mater ; 314: 181-187, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27131458

RESUMO

In this work, a novel approach was applied to obtain the mineralization of 2-chlorophenol (2-CP) in an electrochemical-biological combined system where an electrocatalytic dehydrogenation process (reductive dechlorination) was coupled to a biological denitrification process. Reductive dechlorination of 2-CP was conducted in an ECCOCEL-type reactor on a Pd-Ni/Ti electrode at a potential of -0.40V vs Ag/AgCl(s)/KCl(sat), achieving 100 percent transformation of 2-CP into phenol. The electrochemically pretreated effluent was fed to a rotating cylinder denitrifying bioreactor where the totality of phenol was mineralized by denitrification, obtaining CO2 and N2 as the end products. The total time required for 2-CP mineralization in the combined electrochemical-biological process was 7.5h. This value is close to those previously reported for electrochemical and advanced oxidation processes but in this case, an efficient process was obtained without accumulation of by-products or generation of excessive energy costs due to the selective electrochemical pretreatment. This study showed that the use of electrochemical reductive pretreatment combined with biological processes could be a promising technology for the removal of recalcitrant molecules, such as chlorophenols, from wastewaters by more efficient, rapid, and environmentally friendly processes.


Assuntos
Biodegradação Ambiental , Clorofenóis/metabolismo , Halogenação , Reatores Biológicos , Eletrodos
16.
Water Res ; 104: 547-557, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27660914

RESUMO

Wet-weather discharges contribute to anthropogenic micropollutant loads entering the aquatic environment. Thousands of wet-weather discharges exist in Swiss sewer systems, and we do not have the capacity to monitor them all. We consequently propose a model-based approach designed to identify critical discharge points in order to support effective monitoring. We applied a dynamic substance flow model to four substances representing different entry routes: indoor (Triclosan, Mecoprop, Copper) as well as rainfall-mobilized (Glyphosate, Mecoprop, Copper) inputs. The accumulation on different urban land-use surfaces in dry weather and subsequent substance-specific wash-off is taken into account. For evaluation, we use a conservative screening approach to detect critical discharge points. This approach considers only local dilution generated onsite from natural, unpolluted areas, i.e. excluding upstream dilution. Despite our conservative assumptions, we find that the environmental quality standards for Glyphosate and Mecoprop are not exceeded during any 10-min time interval over a representative one-year simulation period for all 2500 Swiss municipalities. In contrast, the environmental quality standard is exceeded during at least 20% of the discharge time at 83% of all modelled discharge points for Copper and at 71% for Triclosan. For Copper, this corresponds to a total median duration of approximately 19 days per year. For Triclosan, discharged only via combined sewer overflows, this means a median duration of approximately 10 days per year. In general, stormwater outlets contribute more to the calculated effect than combined sewer overflows for rainfall-mobilized substances. We further evaluate the Urban Index (Aurban,impervious/Anatural) as a proxy for critical discharge points: catchments where Triclosan and Copper exceed the corresponding environmental quality standard often have an Urban Index >0.03. A dynamic substance flow analysis allows us to identify the most critical discharge points to be prioritized for more detailed analyses and monitoring. This forms a basis for the efficient mitigation of pollution.


Assuntos
Monitoramento Ambiental , Tempo (Meteorologia) , Cidades , Poluição Ambiental , Modelos Teóricos , Chuva , Movimentos da Água
17.
Biosens Bioelectron ; 49: 367-73, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23796536

RESUMO

A highly sensitive and selective molecularly imprinted (MIP) sensor combined with magnetic molecularly imprinted solid phase extraction (MMISPE) was developed for the determination of dibutyl phthalate (DBP) in complex matrixes. The magnetic molecularly imprinted polymer (MMIP) was synthesized as solid phase extraction (SPE) sorbet to extract DBP from complex matrixes and as sensing element to improve the selectivity of the imprinted sensor. The morphologies of MMIP and MIP-sensor were characterized by using scanning electron microscope (SEM) and transmission electron microscopy (TEM). The electrochemical performances of MIP-sensor were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The conditions of preconcentration, elution and electrochemical determination were studied in detail. Under the optimized experimental conditions, the response currents of the MIP-sensor exhibited a linear relationship towards DBP concentrations ranging from 1.0 × 10(-8)g/L to 1.0 × 10(-3)g/L. The limit of detection of the MMIP-sensor coupled with the MMISPE was calculated as 0.052 ng/L. The MMIP-sensor coupled with the MMISPE was applied to detect DBP in complex samples successfully.


Assuntos
Dibutilftalato/análise , Impressão Molecular/métodos , Plastificantes/análise , Extração em Fase Sólida/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção , Magnetismo/métodos
18.
Chemosphere ; 92(10): 1383-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23751125

RESUMO

To achieve better removal of NH4(+) and TP in wastewater, a new algae-bacteria combined system of Chlorella vulgaris and Bacillus licheniformis was investigated in a 6-d experiment. The results showed that 78% of NH4(+) could be removed in the combined system, while 29% in single algae system and only 1% in single bacteria system. Approximately 92% of TP was removed in the combined system, compared with 55% and 78% in single algae and bacteria system, respectively. B. licheniformis was proven to be a growth-promoting bacterium for C. vulgaris by comparing Chl a concentrations in the single and combined systems. In the removal process, pH of the combined system was observed to reduce significantly from 7.0 to 3.5. Whereas with pH regulated to 7.0, higher removal efficiencies of NH4(+) (86%) and TP (93%) were achieved along with the recovery of algal cells and the increase of Chl a. These results suggest that nutrients in wastewater can be removed efficiently by the algae-bacteria combined system and pH control is crucial in the process.


Assuntos
Bacillus/fisiologia , Chlorella vulgaris/fisiologia , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Águas Residuárias/análise , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Compostos de Amônio/isolamento & purificação , Compostos de Amônio/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Fósforo/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo
19.
Mem. Inst. Oswaldo Cruz ; 112(6): 403-410, June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-841808

RESUMO

BACKGROUND Enterocytozoon bieneusi are the most common microsporidia associated with different clinical manifestations such as diarrhoea, respiratory tract inflammation and acalculous cholecystitis, especially in immunocompromised patients. Infection usually occurs by ingestion of food and water contaminated with spores, but can also result from direct contact with spores through broken skin, eye lesions, and sexual transmission, depending on the microsporidian species. Although there are reports of E. bieneusi found in humans and animals in Brazil, there are no published studies of environmental samples examined by molecular methods. OBJECTIVES The purpose of this study was to verify the presence of E. bieneusi in raw sewage and treated effluent from a combined system by molecular methods. METHODS Raw sewage and treated effluent samples collected from a combined system were analysed for the presence of E. bieneusi using the internal transcriber spacer (ITS) region of E. bieneusi by nested polymerase chain reaction. FINDINGS The analysis revealed E. bieneusi presence and a novel genotype (EbRB) in one raw sewage sample and one treated effluent. MAIN CONCLUSIONS The presence of E. bieneusi in final effluent indicates that the combined system may not remove microsporidian spores. This study is the first report of E. bieneusi in environmental samples in Brazil.


Assuntos
DNA Fúngico/genética , Reação em Cadeia da Polimerase , Enterocytozoon/isolamento & purificação , Enterocytozoon/genética , Filogenia , Brasil , Análise de Sequência , Genótipo
20.
Eng. sanit. ambient ; 20(1): 103-110, Jan-Mar/2015. tab, graf
Artigo em Português | LILACS | ID: lil-750711

RESUMO

O estudo visou a investigação da degradação de formaldeído em um sistema combinado anaeróbio-aeróbio, de fluxo ascendente e com biomassa imobilizada, constituindo-se por um filtro anaeróbio seguido de biofiltro aerado submerso. As concentrações de formaldeído aplicadas ao sistema variaram de 26 a 1.055 mg HCHO.L-1, resultando em eficiências de remoção de formaldeído de 97±3% e de DQO de 90±6%. A partir dos resultados obtidos, conclui-se que o sistema combinado se apresentou adequado para o tratamento de esgoto sanitário contendo formaldeído, uma vez que além de eficiências de remoção representativas, apresentou estabilidade de operação durante o decorrer do estudo.


The study aimed to investigate the degradation of formaldehyde in an anaerobic-aerobic combined system, upflow and with immobilized biomass, consisting of an Anaerobic Filter (AF) followed by Aerated Submerged Biofilter (ASB). The concentrations of formaldehyde applied to the system ranged from 26 to 1,055 mg HCHO.L-1, resulted in a removal efficiency of formaldehyde of 97±3% and chemical oxygen demand (COD) of 90±6%. From the results, it is concluded that the combined system was suitable for treating wastewater containing formaldehyde, since besides representative removal efficiencies; operation was stable during the course of the study.

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