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This study explores how water content modulates the self-assembly and fluorescence behavior of a novel calixarene, C1. C1 forms large, flattened structures in pure THF, but water addition triggers a transition to smaller, unimodal clusters. A critical micellar concentration (CMC) is identified, decreasing with increasing water content. Fluorescence quenching is observed upon water addition, attributed to nonradiative deactivation. These findings highlight water as a key regulator of C1's assembly and fluorescence, paving the way for further development of water-responsive calixarene systems.
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Providencia rustigianii is potentially enteropathogenic in humans. Recently, we identified a P. rustigianii strain carrying a part of the cdtB gene homologous to that of Providencia alcalifacines that produces an exotoxin called cytolethal distending toxin (CDT), encoded by three subunit genes (cdtA, cdtB, and cdtC). In this study, we analyzed the P. rustigianii strain for possible presence of the entire cdt gene cluster and its organization, location, and mobility, as well as expression of the toxin as a putative virulence factor of P. rustigianii. Nucleotide sequence analysis revealed the presence of the three cdt subunit genes in tandem, and over 94% homology to the corresponding genes carried by P. alcalifaciens both at nucleotide and amino acid sequence levels. The P. rustigianii strain produced biologically active CDT, which caused distension of eukaryotic cell lines with characteristic tropism of CHO and Caco-2 cells but not of Vero cells. S1-nuclease digested pulsed-field gel electrophoresis followed by Southern hybridization analysis demonstrated that the cdt genes in both P. rustigianii and P. alcalifaciens strains are located on large plasmids (140 to 170 kb). Subsequently, conjugation assays using a genetically marked derivative of the P. rustigianii strain showed that the plasmid carrying cdt genes in the P. rustigianii was transferable to cdt gene-negative recipient strains of P. rustigianii, Providencia rettgeri, and Escherichia coli. Our results demonstrated the presence of cdt genes in P. rustigianii for the first time, and further showed that the genes are located on a transferable plasmid, which can potentially spread to other bacterial species.
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Escherichia coli , Providencia , Animais , Chlorocebus aethiops , Humanos , Providencia/genética , Células Vero , Células CACO-2 , Escherichia coli/genéticaRESUMO
BACKGROUND: Representative data describing serious infections in children aged ≥5 years and adults in Africa are limited. METHODS: We conducted population-based surveillance for pneumonia, meningitis, and septicemia in a demographic surveillance area in The Gambia between 12 May 2008 and 31 December 2015. We used standardized criteria to identify, diagnose, and investigate patients aged ≥5 years using conventional microbiology and radiology. RESULTS: We enrolled 1638 of 1657 eligible patients and investigated 1618. Suspected pneumonia, septicemia, or meningitis was diagnosed in 1392, 135, and 111 patients, respectively. Bacterial pathogens from sterile sites were isolated from 105 (7.5%) patients with suspected pneumonia, 11 (8.1%) with suspected septicemia, and 28 (25.2%) with suspected meningitis. Streptococcus pneumoniae (n = 84), Neisseria meningitidis (n = 16), and Staphylococcus aureus (n = 15) were the most common pathogens. Twenty-eight (1.7%) patients died in hospital and 40 (4.1%) died during the 4 months after discharge. Thirty postdischarge deaths occurred in patients aged ≥10 years with suspected pneumonia. The minimum annual incidence was 133 cases per 100 000 person-years for suspected pneumonia, 13 for meningitis, 11 for septicemia, 14 for culture-positive disease, and 46 for radiological pneumonia. At least 2.7% of all deaths in the surveillance area were due to suspected pneumonia, meningitis, or septicemia. CONCLUSIONS: Pneumonia, meningitis, and septicemia in children aged ≥5 years and adults in The Gambia are responsible for significant morbidity and mortality. Many deaths occur after hospital discharge and most cases are culture negative. Improvements in prevention, diagnosis, inpatient, and follow-up management are urgently needed.
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Meningites Bacterianas , Meningite , Pneumonia , Sepse , Criança , Humanos , Adulto , Lactente , Adolescente , Gâmbia/epidemiologia , Assistência ao Convalescente , Alta do Paciente , Meningites Bacterianas/epidemiologiaRESUMO
We conducted a genomic analysis of monkeypox virus sequences collected early in the 2022 outbreak, during July-August , in Washington, USA. Using 109 viral genomes, we found low overall genetic diversity, multiple introductions into the state, ongoing community transmission, and potential for co-infections by multiple strains.
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Monkeypox virus , Mpox , Humanos , Monkeypox virus/genética , Mpox/epidemiologia , Washington , Genômica , Surtos de DoençasRESUMO
BACKGROUND: Respiratory tract infections (RTIs) are the most common reason for prescribing antibiotics in general practice. The COVID-19 pandemic has impacted on antibiotic prescribing and delivery of primary care in Ireland. OBJECTIVES: To assess the quality of antibiotic prescribing, the impact of the COVID-19 pandemic and identify opportunities for antimicrobial stewardship (AMS) in Ireland. METHODS: Point prevalence audit surveys for RTI consultations were conducted as part of a European study at three time periods: January-February 2020, March-May 2020 and March-May 2021. Antibiotic prescribing was assessed and comparisons made between the three time periods. RESULTS: In total, 765 consultations were recorded, which were mainly face to face before the pandemic, but changed to predominantly remote consultations during the pandemic surveys in 2020 and 2021 (82% and 75%). Antibiotics were prescribed in 54% of RTI consultations before the pandemic. During pandemic surveys, this dropped to 23% in 2020 and 21% in 2021. There was a decrease in prescribing of Red (reserve) agents in 2021. Assessment against indication-specific quality indicators showed a high proportion of consultations for bronchitis and tonsillitis resulting in an antibiotic prescription (67% and 85%). Point-of-care testing (POCT) to aid diagnosis of RTIs were utilized in less than 1% of consultations. CONCLUSIONS: During the COVID-19 pandemic, there was a reduction in antibiotic prescribing. Opportunities identified to support AMS in primary care in Ireland are targeted initiatives to reduce antibiotic prescribing for bronchitis and tonsillitis and introducing POCT to support appropriate antibiotic prescribing.
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Bronquite , COVID-19 , Infecções Respiratórias , Tonsilite , Humanos , COVID-19/epidemiologia , Pandemias , Irlanda/epidemiologia , Prevalência , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/epidemiologia , Encaminhamento e Consulta , Antibacterianos/uso terapêutico , Atenção Primária à Saúde , Padrões de Prática Médica , Prescrição InadequadaRESUMO
Nickel-based oxides are selected for their inexpensive cost, well-defined redox activity, and flexibility in adjusting nanostructures via optimization of the synthesis process. This communique explores the field of energy storage for hydrothermally synthesized NiO/ZnO nanowires by analysing their capacitive behaviour. The p-type NiO was successfully built onto the well-ordered mesoporous n-type ZnO matrix, resulting in the formation of p-n heterojunction artefacts with porous nanowire architectures. NiO/ZnO nanowire-based electrodes exhibited much higher electrochemical characteristics than bare NiO nanowires. The heterojunction at the interface between the NiO and ZnO nanoparticles, their specific surface area, as well as their combined synergetic influence, are accountable for the high specific capacitance (Cs) of 1135 Fg-1at a scan rate of 5 mV s-1. NiO/ZnO nanowires show an 18% dip in initial capacitance even after 6000 cycles, indicating excellent capacitance retention and low resistance validated by electrochemical impedance spectroscopy. In addition, the specific capacitance, energy and power density of the solid state asymmetric capacitor that was manufactured by employing NiO/ZnO as the positive electrode and activated carbon as the negative electrode were found to be 87 Fg-1, 23 Whkg-1and 614 Wkg-1, respectively. The novel electrode based on NiO/ZnO demonstrates excellent electrochemical characteristics all of which point to its promising application in supercapacitor devices.
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Hippocampal sclerosis (HS) is often associated with gray-white matter blurring (GMB) of the anterior temporal lobe. In this study, twenty patients with unilateral temporal lobe epilepsy and HS were studied with 3 T MRI including T1 MP2RAGE and DTI/DMI sequences. Anterior temporal lobe white matter T1 relaxation times and diffusion measures were analyzed on the HS side, on the contralateral side, and in 10 normal controls. Resected brain tissue of three patients without GMB and four patients with GMB was evaluated ultrastructurally regarding axon density and diameter, the relation of the axon diameter to the total fiber diameter (G-ratio), and the thickness of the myelin sheath. Hippocampal sclerosis GMB of the anterior temporal lobe was related to prolonged T1 relaxation and axonal loss. A less pronounced reduction in axonal fraction was also found on imaging in GMB-negative temporal poles compared with normal controls. Contralateral values did not differ significantly between patients and normal controls. Reduced axonal density and axonal diameter were histopathologically confirmed in the temporopolar white matter with GMB compared to temporal poles without. These results confirm that GMB can be considered an imaging correlate for disturbed axonal maturation that can be quantified with advanced diffusion imaging.
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Epilepsia do Lobo Temporal , Doenças Neurodegenerativas , Substância Branca , Epilepsia do Lobo Temporal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Esclerose/complicações , Esclerose/patologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologiaRESUMO
OBJECTIVE: Provision of analgesia for injured children is challenging for Emergency Medical Services (EMS) clinicians. Little is known about the effect of prehospital analgesia on emergency department (ED) care. We aimed to determine the impact of prehospital pain interventions on initial ED pain scale scores, timing and dosing of ED analgesia for injured patients transported by EMS. METHODS: This is a planned, secondary analysis of a prospective multicenter cohort of children with actual or suspected injuries transported to one of 11 PECARN-affiliated EDs from July 2019-April 2020. Using Wilcoxon rank sum for continuous variables and chi-square testing for categorical variables, we compared the change in EMS-to-ED pain scores and timing and dosing of ED-administered opioid analgesia in those who did and those who did not receive prehospital pain interventions. RESULTS: We enrolled 474 children with complete prehospital and ED pain management data. Prehospital interventions were performed on 262/474 (55%) of injured children and a total of 88 patients (19%) received prehospital opioids. Children who received prehospital opioids with or without adjunctive non-pharmacologic pain management experienced a greater reduction in pain severity and were more likely to receive ED opioids in higher doses earlier and throughout their ED care. Non-pharmacologic pain interventions alone did not impact ED care. CONCLUSIONS: We demonstrate that prehospital opioid analgesia is associated with both a significant reduction in pain severity at ED arrival and the administration of higher doses of opioid analgesia earlier and throughout ED care.
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Serviços Médicos de Emergência , Manejo da Dor , Humanos , Criança , Analgésicos Opioides/uso terapêutico , Estudos Prospectivos , Serviço Hospitalar de Emergência , Dor/tratamento farmacológico , Analgésicos/uso terapêutico , Estudos RetrospectivosRESUMO
Propellant mass gauging under micro-gravity conditions is a challenging task due to the unpredictable position and shape of the fuel body inside the tank. Micro-gravity conditions are common for orbiting satellites and rockets that operate on limited fuel supplies. Capacitance sensors have been investigated for this task in recent years; however, the effect of various positions and shapes of the fuel body is not analyzed in detail. In this paper, we investigate this with various fill types, such as annular, core-annular, and stratified fills at different positions. We compare the performance among several curve-fitting-based approaches and a machine-learning-based approach, the latter of which offers superior performance in estimating the fuel content.
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Lately, semiconductor-membrane fuel cells (SMFCs) have attained significant interest and great attention due to the deliverance of high performance at low operational temperatures, <550 °C. This work has synthesized the nanocomposite core-shell heterostructure (TiO2 -SrTiO3 ) electrolyte powder by employing the simple hydrothermal method for the SMFC. The SrTiO3 was grown inâ situ on the surface of TiO2 to form a core-shell structure. A heterojunction mechanism based on the energy band structure is proposed to explain the ion transport pathway and promoted protonic conductivity. The core-shell heterostructure (TiO2 -SrTiO3 ) was utilized as an electrolyte to reach the peak power density of 951â mW cm-2 with an open-circuit voltage of 1.075â V at 550 °C. The formation of core-shell heterostructure among TiO2 and SrTiO3 causes redistribution of charges and establishes a depletion region at the interface, which confined the protons' transport on the surface layer with accelerated ion transport and lower activation energy. The current work reveals novel insights to understand enhanced proton transport and unique methodology to develop low-temperature ceramic fuel cells with high performance.
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The front cover artwork is provided by Prof. Faze Wang's group at the Southeast University. The built-in electric field created by the semiconductor heterostructure confines the proton transport on the surface layer of the nanocomposite core-shell heterostructure imparting faster ion transport and lower activation energy. Read the full text of the Research Article at 10.1002/cphc.202200170.
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BACKGROUND: Risankizumab has demonstrated efficacy and safety in patients with moderate-to-severe plaque psoriasis in randomized clinical trials. OBJECTIVES: To evaluate safety data from risankizumab psoriasis phase I-III clinical trials. METHODS: Short-term safety (through week 16) was analysed using integrated data from five phase II and III clinical trials. Long-term safety was evaluated using integrated data from 17 phase I-III completed and ongoing trials. RESULTS: Short-term safety analyses included 1306 patients receiving risankizumab 150 mg and 300 patients receiving placebo [402·2 and 92·0 patient-years (PY) of exposure, respectively]. Long-term analyses included 3072 risankizumab-treated patients (exposure: 7927 PY). The median (excluding four outliers) treatment duration was 2·9 years (range 2 days to 5·9 years). Exposure-adjusted adverse event rates did not increase with long-term treatment (318 vs. 171 events per 100 PY for short- and long-term analyses). With long-term risankizumab treatment, rates of serious adverse events were 7·8 per 100 PY, serious infections 1·2 per 100 PY, nonmelanoma skin cancer (NMSC) 0·7 per 100 PY, malignant tumours excluding NMSC 0·5 per 100 PY, and adjudicated major adverse cardiovascular events 0·3 per 100 PY, with no important identified risks. Limitations include that the study inclusion and exclusion criteria varied and that three studies enrolled ≤ 50 patients. CONCLUSIONS: Risankizumab demonstrated a favourable safety profile over short- and long-term treatment in patients with moderate-to-severe psoriasis.
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Anticorpos Monoclonais , Psoríase , Anticorpos Monoclonais/efeitos adversos , Ensaios Clínicos como Assunto , Humanos , Psoríase/tratamento farmacológico , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
OBJECTIVE: To assess national and regional trends and causes-specific distribution of maternal mortality in India. DESIGN: Nationally representative cross-sectional surveys. SETTING: All of India from 1997 to 2020. SAMPLE: About 10 000 maternal deaths among 4.3 million live births over two decades. METHODS: We analysed trends in the maternal mortality ratio (MMR) from 1997 through 2020, estimated absolute maternal deaths and examined the causes of maternal death using nationally representative data sources. We partitioned female deaths (aged 15-49 years) and live birth totals, based on the 2001-2014 Million Death Study to United Nations (UN) demographic totals for the country. MAIN OUTCOME MEASURES: Maternal mortality burden and distribution of causes. RESULTS: The MMR declined in India by about 70% from 398/100 000 live births (95% CI 378-417) in 1997-98 to 99/100 000 (90-108) in 2020. About 1.30 million (95% CI 1.26-1.35 million) maternal deaths occurred between 1997 and 2020, with about 23 800 (95% CI 21 700-26 000) in 2020, with most occurring in poorer states (63%) and among women aged 20-29 years (58%). The MMRs for Assam (215), Uttar Pradesh/Uttarakhand (192) and Madhya Pradesh/Chhattisgarh (170) were highest, surpassing India's 2016-2018 estimate of 113 (95% CI 103-123). After adjustment for education and other variables, the risks of maternal death were highest in rural and tribal areas of north-eastern and northern states. The leading causes of maternal death were obstetric haemorrhage (47%; higher in poorer states), pregnancy-related infection (12%) and hypertensive disorders of pregnancy (7%). CONCLUSIONS: India could achieve the UN 2030 MMR goals if the average rate of reduction is maintained. However, without further intervention, the poorer states will not. TWEETABLE ABSTRACT: We estimated that 1.3 million Indian women died from maternal causes over the last two decades. Although maternal mortality rates have fallen by 70% overall, the poorer states lag behind.
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Nascido Vivo/epidemiologia , Mortalidade Materna , Adolescente , Adulto , Feminino , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Gravidez , Adulto JovemRESUMO
Ecological restoration of coal mine degraded soils across arid and semi-arid environments worldwide remains particularly challenging. We used a combination of greenhouse and field experiments to assess the potential role of a woody species, Ulmus pumila, in the restoration of degraded soils associated with coal-mining activities in the northwest China. We investigated how various combinations of water-nitrogen-phosphorus (W-N-P) resources affect multiple growth parameters in U. pumila. We found that several plant growth traits significantly improved with W-N applications, regardless of P inputs. Moderate-to-highest W-N-P doses increased net photosynthesis and transpiration rates, water use efficiency, stomatal conductance, chlorophyll and carotenoid contents under greenhouse conditions. A combination of high W together with low N-P applications led to high relative water content and net photosynthetic rates under field conditions. Increasing of N-P doses under W-shortage condition, aided U. pumila to enhance osmotic adjustments by increasing contents of proline and soluble sugar and also boost the activity of superoxide dismutase, peroxidase and catalase in leaf tissues to reduce accumulation of reactive oxygen species and malondialdehyde content in all conditions of greenhouse and field. Our study is the first to assess the optimum W-N-P resources in U. pumila and demonstrate that optimum growth performance could be obtained under W supplements corresponding to 90 mm year-1, N and P at 110 and 45 kg ha-1, respectively, under field condition. These findings can have far reaching implications for vegetation restoration of degraded areas associated with coal-mining activities across arid and semi-arid regions worldwide.
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Carvão Mineral , Água , Nutrientes , Solo , MadeiraRESUMO
Objective: Linking emergency medical services (EMS) data to hospital outcomes is important for quality assurance and research initiatives. However, non-linkage due to missing or incomplete patient information may increase the risk of bias and distort findings. The purpose of this study was to explore if an optimization strategy, in addition to an existing linkage process, improved the linkage rate and reduced selection and information bias. Methods: 4,150 transported patients in a metropolitan EMS system in Alberta, Canada from 2016/17 were linked to two Emergency Department (ED) databases by a standard strategy using a unique health care number, date/time of ED arrival, and hospital name. An optimized strategy added additional linkage steps incorporating last name, year of birth, and a manual search. The strategies were compared to assess the rate of linkage, and to describe event and patient-level characteristics of unlinked records. Results: The standard strategy resulted in 3,650 out of 4,150 (88.0%) linked records (95% CI 86.9%-88.9%). Of the 500 non-linked records, an additional 381 were linked by the optimized strategy (n = 4,031/4,150 [97.1%; 95% CI: 96.6%-97.6%]). There were no false positive linkages. The highest linkage failure was in 25 to 34 year-old patients (n = 93/478, 19.5%), males (n = 236/1975, 12.0%), Echo level events (n = 15/77, 19.5%), and emergency transport (45/231, 19.5%). The optimized strategy improved linkage in these groups by 68.8% (64/93), 79.2% (187/236), 40.0% (6/15), and 51.1% (23/45) respectively. For dispatch card, the highest linkage failure occurred in Card 24-Pregnancy/Childbirth/Miscarriage (n = 30/44, 68.2%), Card 27-Stab/Gunshot/Penetrating Trauma (n = 6/17, 35.3%), and Card 9-Cardiac/Respiratory Arrest/Death (n = 12/46, 26.1%). The optimized strategy improved linkage by 10.0% (3/30), 83.3% (5/6), and 41.7% (5/12) respectively. For the 119 unlinked records, 71 (59.7%) had sufficient information for linkage, but no appropriately matching records could be found. Conclusion: An optimized sequential deterministic strategy linking EMS data to ED outcomes improved the linkage rate without increasing the number of false positive links, and reduced the potential for bias. Even with adequate information, some records were not linked to their ED visit. This study underscores the importance of understanding how data are linked to hospital outcomes in EMS research and the potential for bias.
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Serviços Médicos de Emergência , Ferimentos por Arma de Fogo , Masculino , Humanos , Adulto , Hospitais , Bases de Dados Factuais , Canadá , Serviço Hospitalar de EmergênciaRESUMO
Phaseolus vulgaris-Colletotrichum lindemuthianum is one among the oldest host and pathogen interface. Researchers have taken painstaking efforts across the world for understanding the dialogue during early and late phases of interaction. Collectively, these efforts resulted in the deluge of information that helped the researchers to underpin the interface. The latest molecular biology techniques furnished novel detection methods for the anthracnose pathogen, refined the understanding of pathogen population dynamics, and provided the insights on co-evolutionary common bean resistance and C. lindemuthianum virulence dynamics. One of the important breakthroughs came when the Phaseolus vulgaris and its corresponding anthracnose pathogen (C. lindemuthianum) genomes were decoded in 2014 and 2017, respectively. Availability of both the genomes yielded a significant genomic information that helped bean communities to fine map the economically important traits and to identify the pathogenicity determinants and effector molecules. The interface is in a continuous development as knowledge of the anthracnose resistance genes, their precise physical locations, and the identification of effector proteins; the fungus arsenals are being routinely updated. Hence, we revisited the interface and tried to provide an overview of host pathogen dialogue in the genomic era. Additionally, we compiled the sporadic information on this pathosystem from India and provided its futuristic road map to shape its research in the world and northern India, the major dry bean area in the country.
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Colletotrichum , Phaseolus , Genômica , Doenças das PlantasRESUMO
In the recent past, wastewater treatment processes performed a pivotal role in accordance with maintaining the sustainable environment and health of mankind at a proper hygiene level. It has been proved indispensable by government regulations throughout the world on account of the importance of preserving freshwater bodies. Human activities, predominantly from industrial sectors, generate an immeasurable amount of industrial wastewater loaded with toxic chemicals, which not only cause dreadful environmental problems, but also leave harmful impacts on public health. Hence, industrial wastewater effluent must be treated before being released into the environment to restrain the problems related to industrial wastewater discharged to the environment. Nowadays, biological wastewater treatment methods have been considered an excellent approach for industrial wastewater treatment process because of their cost-effectiveness in the treatment, high efficiency and their potential to counteract the drawbacks of conventional wastewater treatment methods. Recently, the treatment of industrial effluent through bioreactor has been proved as one of the best methods from the presently available methods. Reactors are the principal part of any biotechnology-based method for microbial or enzymatic biodegradation, biotransformation and bioremediation. This review aims to explore and compile the assessment of the most appropriate reactors such as packed bed reactor, membrane bioreactor, rotating biological contactor, up-flow anaerobic sludge blanket reactor, photobioreactor, biological fluidized bed reactor and continuous stirred tank bioreactor that are extensively used for distinct industrial wastewater treatment.
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Eliminação de Resíduos Líquidos , Purificação da Água , Anaerobiose , Reatores Biológicos , Humanos , Resíduos Industriais , Esgotos , Águas ResiduáriasRESUMO
Microbial fuel cell (MFC) is an emerging technology which has been immensely investigated for wastewater treatment along with electricity generation. In the present study, the treatment efficiency of MFC was investigated for hydrocarbon containing wastewater by optimizing various parameters of MFC. Mediator-less MFC (1·2 l) was constructed, and its performance was compared with mediated MFC with Escherichia coli as a biocatalyst. MFC with electrode having biofilm proved to be better compared with MFC inoculated with suspended cells. Analysis of increasing surface area of electrode by increasing their numbers indicated increase in COD reduction from 55 to 75%. Catholyte volume was optimized to be 750 ml. Sodium benzoate (0·721 g l-1 ) and actual common effluent treatment plant (CETP) wastewater as anolyte produced 0·8 and 0·6 V voltage and 89 and 50% COD reduction, respectively, when a novel consortium of four bacterial strains were used. Twenty MFC systems with the developed consortium when electrically connected in series-parallel connection were able to generate 2·3 V and 0·5 mA current. This is the first report demonstrating the application of CETP wastewater in the MFC system, which shows potential of the system towards degradation of complex organic components present in industrial wastewater.
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Fontes de Energia Bioelétrica , Purificação da Água , Biodegradação Ambiental , Fontes de Energia Bioelétrica/microbiologia , Eletricidade , Eletrodos , Benzoato de Sódio , Águas ResiduáriasRESUMO
Heavy metals-containing drinking water and wastewater are posing a severe threat to the environment, and living beings on land, air and water. Different conventional, advanced nanomaterials-based and biological method has been employed for the treatment of heavy metals. Among the biological methods, microalgae are an important group of micro-organisms that have numerous environmental applications and can remediate heavy metals from wastewater. Also, it has numerous advantages over conventional remediation processes. Microalgae cells can uptake the heavy metal via different physiological and biological methods and are utilized as a nutrient source to regulate its metabolic process for the production of biomass. Furthermore, the enhancement in heavy metal removal efficiency can be improved using different strategies such as immobilization of algal cells, development of algal consortia and designing of microalgae-based nanocomposite materials. Also, it can significantly contribute towards environmental sustainability and future. Thus, the review provides a critical overview of heavy metals and their existence along with their negative effects on humans. This review provides insight on recent advanced nanomaterial approaches for the removal of heavy metals, overviews of microalgae-based heavy metal uptake mechanisms and their potential for the amputation of different heavy metals. Furthermore, the special focus is on recent strategies that enhance heavy metal removal efficiency and contribute towards sustainability for the development of a microalgae-based future.
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Água Potável , Metais Pesados , Microalgas , Biodegradação Ambiental , Biomassa , Humanos , Metais Pesados/metabolismo , Microalgas/metabolismo , Águas ResiduáriasRESUMO
The industries and metropolitan wastes produced by anthropogenic activities are of great concern for nature as it causes soil contamination and deteriorate the environment. Plastic utilization is rapidly enhancing globally with passing days that last for a more extended period in the environment due to slow decomposition and natural degradation. Excessive use of polymer has risked the life of both marine, freshwater and terrestrial organisms. Lack of proper waste management and inappropriate disposal leads to environmental threats. Bioremediation processes involve microbes such as fungi, bacteria, etc. which contribute a crucial role in the breakdown of plastics. Extremophiles secrete extremozymes that are functionally active in extreme conditions and are highly crucial for polymer disaggregation in those conditions.