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1.
Appl Environ Microbiol ; 90(3): e0236523, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38407065

RESUMO

In our paper, we reported the bidirectional extracellular electron transfer capability of Geoalkalibacter halelectricus based on biochemical (i.e., with insoluble Fe-oxide and Fe(0)) and bioelectrochemical (i.e., with electrodes) experimental approaches. We noticed some issues and limitations of the methods and techniques that were used to analyze Fe species, particularly the reduced Fe ions in insoluble and precipitated Fe(II) minerals that led to incorrect interpretation of the results, specifically the reduction of Fe(III) to Fe(0) in this study. We were made aware of thermodynamic constraints that would make the biological reduction of Fe(III) to Fe(0) implausible. Hence, the conclusion about microbial Fe(III)-oxide reduction to Fe(0) is invalid. We also noticed errors in estimating the protein-based iron reduction/oxidation rates and faradic efficiencies, besides the limitations of the methods used for Fe analysis. For these reasons, we retract this article and sincerely apologize for the inconvenience it may have caused to the readers.

2.
Clin Infect Dis ; 77(Suppl 1): S38-S45, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37406039

RESUMO

BACKGROUND: Drug-resistant gram-negative (GN) pathogens are a common cause of neonatal sepsis in low- and middle-income countries. Identifying GN transmission patterns is vital to inform preventive efforts. METHODS: We conducted a prospective cohort study, 12 October 2018 to 31 October 2019 to describe the association of maternal and environmental GN colonization with bloodstream infection (BSI) among neonates admitted to a neonatal intensive care unit (NICU) in Western India. We assessed rectal and vaginal colonization in pregnant women presenting for delivery and colonization in neonates and the environment using culture-based methods. We also collected data on BSI for all NICU patients, including neonates born to unenrolled mothers. Organism identification, antibiotic susceptibility testing, and next-generation sequencing (NGS) were performed to compare BSI and related colonization isolates. RESULTS: Among 952 enrolled women who delivered, 257 neonates required NICU admission, and 24 (9.3%) developed BSI. Among mothers of neonates with GN BSI (n = 21), 10 (47.7%) had rectal, 5 (23.8%) had vaginal, and 10 (47.7%) had no colonization with resistant GN organisms. No maternal isolates matched the species and resistance pattern of associated neonatal BSI isolates. Thirty GN BSI were observed among neonates born to unenrolled mothers. Among 37 of 51 BSI with available NGS data, 21 (57%) showed a single nucleotide polymorphism distance of ≤5 to another BSI isolate. CONCLUSIONS: Prospective assessment of maternal GN colonization did not demonstrate linkage to neonatal BSI. Organism-relatedness among neonates with BSI suggests nosocomial spread, highlighting the importance of NICU infection prevention and control practices to reduce GN BSI.


Assuntos
Anti-Infecciosos , Doenças Transmissíveis , Infecção Hospitalar , Sepse , Recém-Nascido , Humanos , Feminino , Gravidez , Estudos Prospectivos , Unidades de Terapia Intensiva Neonatal , Infecção Hospitalar/epidemiologia , Preparações Farmacêuticas
3.
Appl Environ Microbiol ; : e0060923, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37681980

RESUMO

Bidirectional extracellular electron transfer (EET) is crucial to upholding microbial metabolism with insoluble electron acceptors or donors in anoxic environments. Investigating bidirectional EET-capable microorganisms is desired to understand the cell-cell and microbe-mineral interactions and their role in mineral cycling besides leveraging their energy generation and conversion, biosensing, and bio-battery applications. Here, we report on iron cycling by haloalkaliphilic Geoalkalibacter halelectricus via bidirectional EET under haloalkaline conditions. It efficiently reduces Fe3+ oxide (Fe2O3) to Fe0 at a 0.75 ± 0.08 mM/mgprotein/d rate linked to acetate oxidation via outward EET and oxidizes Fe0 to Fe3+ at a 0.24 ± 0.03 mM/mgprotein/d rate via inward EET to reduce fumarate. Bioelectrochemical cultivation confirmed its outward and inward EET capabilities. It produced 895 ± 23 µA/cm2 current by linking acetate oxidation to anode reduction via outward EET and reduced fumarate by drawing electrons from the cathode (‒2.5 ± 0.3 µA/cm2) via inward EET. The cyclic voltammograms of G. halelectricus biofilms revealed redox moieties with different formal potentials, suggesting the involvement of different membrane components in bidirectional EET. The cyclic voltammetry and GC-MS analysis of the cell-free spent medium revealed the lack of soluble redox mediators, suggesting direct electron transfer by G. halelecctricus in achieving bidirectional EET. By reporting on the first haloalkaliphilic bacterium capable of oxidizing and reducing insoluble Fe0 and Fe3+ oxide, respectively, this study advances the limited understanding of the metabolic capabilities of extremophiles to respire on insoluble electron acceptors or donors via bidirectional EET and invokes the possible role of G. halelectricus in iron cycling in barely studied haloalkaline environments. IMPORTANCE Bidirectional extracellular electron transfer (EET) appears to be a key microbial metabolic process in anoxic environments that are depleted in soluble electron donor and acceptor molecules. Though it is an ecologically important and applied microbial phenomenon, it has been reported with a few microorganisms, mostly from nonextreme environments. Moreover, direct electron transfer-based bidirectional EET is studied for very few microorganisms with electrodes in engineered systems and barely with the natural insoluble electron acceptor and donor molecules in anoxic conditions. This study advances the understanding of extremophilic microbial taxa capable of bidirectional EET and its role in barely investigated Fe cycling in highly saline-alkaline environments. It also offers research opportunities for understanding the membrane components involved in the bidirectional EET of G. halelectricus. The high rate of Fe3+ oxide reduction activity by G. halelectricus suggests its possible use as a biocatalyst in the anaerobic iron bioleaching process under neutral-alkaline pH conditions.

4.
Environ Microbiol ; 24(11): 5066-5081, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36066180

RESUMO

The extracellular electron transfer (EET)-capable electroactive microorganisms (EAMs) play crucial roles in mineral cycling and interspecies electron transfer in different environments and are used as biocatalysts in microbial electrochemical technologies. Studying EAMs from extreme environments is desired to advance the electromicrobiology discipline, understanding their unique metabolic traits with implications to extreme microbiology, and develop specific bioelectrochemical applications. Here, we present a novel haloalkaliphilic bacterium named Geoalkalibacter halelectricus SAP-1, isolated from a microbial electroactive biofilm enriched from the haloalkaline lake sediments. It is a rod-shaped Gram-negative heterotrophic anaerobe that uses various carbon and energy sources and respires on soluble and insoluble terminal electron acceptors. Besides 16S-rRNA and whole-genome sequence-based phylogeny, the GGDC values of 21.7%, ANI of 78.5%, and 2.77% genomic DNA GC content difference with the closest validly named species Geoalkalibacter ferrihydriticus (DSM 17813T ) confirmed its novelty. When grown with the solid-state electrode as the only electron acceptor, it produced 460 ± 23 µA/cm2 bioelectrocatalytic current, thereby confirming its electroactivity. Further electrochemical analysis revealed the presence of membrane redox components with a high formal potential, putatively involved in the direct mode of EET. These are distinct from EET components reported for any known electroactive microorganisms, including well-studied Geobacter spp., Shewanella spp., and Desulfuromonas acetexigens. The capabilities of G. halelectricus SAP-1 to respire on soluble and insoluble electron acceptors including fumarate, SO4 2- , Fe3+ , and Mn4+ suggests its role in cycling these elements in haloalkaline environments.


Assuntos
Geobacter , Shewanella , Elétrons , Geobacter/genética , Transporte de Elétrons , Shewanella/metabolismo , Minerais/metabolismo
5.
Pol J Radiol ; 87: e333-e347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35892068

RESUMO

In recent times, India has been in the midst of a notifiable epidemic of mucormycosis (a rare angio-invasive fungal infection), within the ongoing global coronavirus disease 2019 (COVID-19) pandemic. Epidemiological studies have reported the estimated prevalence of mucormycosis to be around 70 times higher in India as compared to the global data, even in the pre-COVID era. However, in the last 3 months, our city witnessed an unprecedented surge in cases of post-COVID-19-associated rhino-orbital-cerebral (ROC) mucormycosis. This pictorial review aims to illustrate the entire imaging spectrum of mucormycosis in the head-neck-face region. Along with the usual sites (nose, paranasal sinuses, orbits), this disease also involves the skull base, palate, temporal bone, and deep neck spaces. Many cases also demonstrated morbid and, at times, fatal intracranial and neurovascular complications. This review also aims to provide a structured reporting template that will prove useful to the radiologists interpreting imaging studies of ROC mucormycosis.

6.
Magn Reson Med ; 86(2): 725-737, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33665929

RESUMO

PURPOSE: To develop an image-based motion-robust diffusion MRI (dMRI) acquisition framework that is able to minimize motion artifacts caused by rigid and nonrigid motion, applicable to both brain and tongue dMRI. METHODS: We developed a novel prospective motion-correction technique in dMRI using a phase image-based real-time motion-detection method (PITA-MDD) with re-acquisition of motion-corrupted images. The prospective PITA-MDD acquisition technique was tested in the brains and tongues of volunteers. The subjects were instructed to move their heads or swallow, to induce motion. Motion-detection efficacy was validated against visual inspection as the gold standard. The effect of the PITA-MDD technique on diffusion-parameter estimates was evaluated by comparing reconstructed fiber tracts using tractography with and without re-acquisition. RESULTS: The prospective PITA-MDD technique was able to effectively and accurately detect motion-corrupted data as compared with visual inspection. Tractography results demonstrated that PITA-MDD motion detection followed by re-acquisition helps in recovering lost and misshaped fiber tracts in the brain and tongue that would otherwise be corrupted by motion and yield erroneous estimates of the diffusion tensor. CONCLUSION: A prospective PITA-MDD technique was developed for dMRI acquisition, providing improved dMRI image quality and motion-robust diffusion estimation of the brain and tongue.


Assuntos
Encéfalo , Imagem de Difusão por Ressonância Magnética , Algoritmos , Artefatos , Encéfalo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Movimento (Física) , Estudos Prospectivos , Língua/diagnóstico por imagem
7.
Biopolymers ; 112(8): e23465, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34242395

RESUMO

The efficient and low-cost way for gene mutation detection and identification are conducive for the detection of disease. Here, we report the electronic characteristics of the gene of breast cancer 1 in four common mutation types: duplication, single nucleotide variant, deletion, and indel. The electronic characteristics are investigated by the combination of density functional theory and non-equilibrium Green's function formulation with decoherence. The magnitude of conductance of these DNA molecules and mutational changes are found to be detectable experimentally. In this study, we also find the significant mutation type dependent on the change of conductance. Hence these mutations are expected to be identifiable. We find deletion type mutation shows the largest change in relative conductance (~97%), whereas the indel mutation shows the smallest change in relative conductance (~27%). Therefore, this work presents a possibility of electronic detection and identification of mutations in DNA, which could be an efficient method as compared to the conventional methods.


Assuntos
Neoplasias da Mama , Genes BRCA2 , Proteína BRCA1/genética , DNA/genética , Eletrônica , Feminino , Genes BRCA1 , Humanos , Mutação
8.
Mol Cell Biochem ; 476(3): 1599-1603, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33405086

RESUMO

DNA hydroxymethylation plays a very important role in some biological processes, such as DNA methylation process. In addition, its presence can also cause some diseases. In this paper, the electrical properties of cytosine hydroxymethylated (Chm) DNA sequences are studied. The density functional theory (DFT) and Landauer-Büttiker framework are used to study the decoherence conductance and transmission of the Chm strands in different configurations, which provides a theoretical basis for the detection of Chm. The results show that the conductance of the hydroxymethylated DNA strand is smaller than that of the native and methylated strands. The length dependence of the Chm strands is also studied. With the length increasing, the conductance becomes larger. This study shows that DNA methylation can be detected electrically.


Assuntos
Citosina/metabolismo , Metilação de DNA , DNA/química , 5-Metilcitosina , Biofísica , Eletrofisiologia , Epigênese Genética , Conformação Molecular , Solventes/química , Temperatura
9.
Reprod Domest Anim ; 55(8): 998-1010, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32515513

RESUMO

The region-specific expression of seminal proteins in testis and excurrent duct system determines the quality and function of the spermatozoa. In the present study, localization and expression of some of the seminal proteins such as insulin-like growth factor receptor 1ß (IGF-1Rß), phosphatidylethanolamine-binding protein 4 (PEBP4), α-tubulin and tissue factor pathway inhibitor 2 (TFPI2) were carried out in testis, excurrent duct system and spermatozoa of buffalo. IGF-1Rß was localized in the cells of the seminiferous tubules of the testis, except in primary spermatocytes. The PEBP4 was localized only in the elongated spermatid, whereas α-tubulin and TFPI2 proteins were localized in all cells of the seminiferous tubule including spermatocyte. In the buffalo spermatozoa, IGF-1Rß, PEBP4, α-tubulin and TFPI2 were localized in the acrosome region, the post-acrosomal region till the tail end, post-acrosome to the entire tail region and the equatorial region, respectively. The study indicates that IGF-1R, α-tubulin and PEBP4 proteins regulate spermatogenesis, whereas TFPI2 may be involved during the zona binding process of the buffalo spermatozoa.


Assuntos
Búfalos/fisiologia , Proteínas de Plasma Seminal/metabolismo , Espermatogênese/fisiologia , Testículo/metabolismo , Animais , Masculino , Análise do Sêmen , Túbulos Seminíferos , Espermatócitos/fisiologia
10.
Urol Int ; 99(1): 63-68, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28490036

RESUMO

INTRODUCTION: Penile fracture is a relatively common phenomenon. The main problem associated with this condition is the lack of patients' awareness on the urgency of the situation. This study reports the different modes of presentations and treatment results. MATERIALS AND METHODS: We reviewed 21 cases of penile fracture over 5 years. Parameters were mode of injury, age group, time interval before presentation, management, site of injury, urethral involvement, results, complications and erectile function at follow-up. RESULTS: The mean age of patients was 34 years, the mean time interval until presentation was 26 h. Cases involving the right corpus cavernosum comprised 57.14% and 42.85% were cases involving the left corpus cavernosum. Two patients had full circumferential urethral tear. Two patients developed wound infections and 2 patients developed mild penile curvature (<30°). These 4 patients had all presented late for treatment (>40 h). CONCLUSION: Urologists need to consider penile fracture a urological emergency and atypical presentations need to be considered when deciding on management.


Assuntos
Doenças do Pênis/etiologia , Pênis/lesões , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças do Pênis/diagnóstico por imagem , Doenças do Pênis/cirurgia , Ereção Peniana , Pênis/diagnóstico por imagem , Pênis/fisiopatologia , Pênis/cirurgia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Ruptura , Infecção da Ferida Cirúrgica/etiologia , Fatores de Tempo , Tempo para o Tratamento , Resultado do Tratamento , Procedimentos Cirúrgicos Urológicos Masculinos/efeitos adversos , Adulto Jovem
11.
Appl Environ Microbiol ; 82(1): 297-307, 2016 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26497463

RESUMO

Hydrocarbons released during oil spills are persistent in marine sediments due to the absence of suitable electron acceptors below the oxic zone. Here, we investigated an alternative bioremediation strategy to remove toluene, a model monoaromatic hydrocarbon, using a bioanode. Bioelectrochemical reactors were inoculated with sediment collected from a hydrocarbon-contaminated marine site, and anodes were polarized at 0 mV and +300 mV (versus an Ag/AgCl [3 M KCl] reference electrode). The degradation of toluene was directly linked to current generation of up to 301 mA m(-2) and 431 mA m(-2) for the bioanodes polarized at 0 mV and +300 mV, respectively. Peak currents decreased over time even after periodic spiking with toluene. The monitoring of sulfate concentrations during bioelectrochemical experiments suggested that sulfur metabolism was involved in toluene degradation at bioanodes. 16S rRNA gene-based Illumina sequencing of the bulk anolyte and anode samples revealed enrichment with electrocatalytically active microorganisms, toluene degraders, and sulfate-reducing microorganisms. Quantitative PCR targeting the α-subunit of the dissimilatory sulfite reductase (encoded by dsrA) and the α-subunit of the benzylsuccinate synthase (encoded by bssA) confirmed these findings. In particular, members of the family Desulfobulbaceae were enriched concomitantly with current production and toluene degradation. Based on these observations, we propose two mechanisms for bioelectrochemical toluene degradation: (i) direct electron transfer to the anode and/or (ii) sulfide-mediated electron transfer.


Assuntos
Biodegradação Ambiental , Deltaproteobacteria/metabolismo , Eletrodos , Sedimentos Geológicos/microbiologia , Enxofre/metabolismo , Tolueno/metabolismo , Anaerobiose , Carbono-Carbono Liases , Hidrocarbonetos/metabolismo , Sulfito de Hidrogênio Redutase/genética , Sulfito de Hidrogênio Redutase/metabolismo , Consórcios Microbianos/fisiologia , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sulfatos/metabolismo , Poluentes Químicos da Água/metabolismo
12.
Nanotechnology ; 27(4): 045201, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26657131

RESUMO

Semiconducting nanowire (NW) devices have garnered attention in self-powered electronic and optoelectronic applications. This work explores and exhibits, for the first time for visible light, clear evidence of the zero-biased optoelectronic switching in randomly dispersed Ge and Si NW networks. The test bench, on which the NWs were dispersed for optoelectronic characterization, was fabricated using a standard CMOS fabrication process, and utilized metal contacts with dissimilar work functions-Al and Ni. The randomly dispersed NWs respond to light by exhibiting substantial photocurrents and, most remarkably, demonstrate zero-bias photo-switching. The magnitude of the photocurrent is dependent on the NW material, as well as the channel length. The photocurrent in randomly dispersed GeNWs was found to be higher by orders of magnitude compared to SiNWs. In both of these material systems, when the length of the NWs was comparable to the channel length, the currents in sparse NW networks were found to be higher than those in dense NW networks, which can be explained by considering various possible arrangements of NWs in these devices.

13.
Environ Sci Technol ; 49(14): 8833-43, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26079858

RESUMO

The advent of renewable energy conversion systems exacerbates the existing issue of intermittent excess power. Microbial electrosynthesis can use this power to capture CO2 and produce multicarbon compounds as a form of energy storage. As catalysts, microbial populations can be used, provided side reactions such as methanogenesis are avoided. Here a simple but effective approach is presented based on enrichment of a robust microbial community via several culture transfers with H2:CO2 conditions. This culture produced acetate at a concentration of 1.29 ± 0.15 g L(-1) (maximum up to 1.5 g L(-1); 25 mM) from CO2 at a fixed current of -5 Am(-2) in fed-batch bioelectrochemical reactors at high N2:CO2 flow rates. Continuous supply of reducing equivalents enabled acetate production at a rate of 19 ± 2 gm(-2)d(-1) (projected cathode area) in several independent experiments. This is a considerably high rate compared with other unmodified carbon-based cathodes. 58 ± 5% of the electrons was recovered in acetate, whereas 30 ± 10% of the electrons was recovered in H2 as a secondary product. The bioproduction was most likely H2 based; however, electrochemical, confocal microscopy, and community analyses of the cathodes suggested the possible involvement of the cathodic biofilm. Together, the enrichment approach and galvanostatic operation enabled instant start-up of the electrosynthesis process and reproducible acetate production profiles.


Assuntos
Acetatos/metabolismo , Bactérias/metabolismo , Fontes de Energia Bioelétrica , Dióxido de Carbono/metabolismo , Técnicas Eletroquímicas/métodos , Bactérias/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Eletrodos , Concentração de Íons de Hidrogênio , Metano/metabolismo , Reprodutibilidade dos Testes
15.
J Magn Reson Imaging ; 40(2): 490-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24677517

RESUMO

PURPOSE: To compare the spatial accuracy of three typical active tracking sequences using a new, unique phantom design. MATERIALS AND METHODS: Three different tracking sequences (Single Echo, Dual Echo and Hadamard Multiplexed) were compared with each other in a phantom study with respect to their positional accuracy. A custom-built phantom was constructed to conduct the experiments with precise framework conditions which facilitated sufficient measurement accuracy. An electrophysiology catheter incorporating four micro-coils was used as an interventional device. Tracking profiles were acquired in all three spatial dimensions and validated against the distances that were measured by a Vernier caliper in combination with a three-dimensional reference scan. RESULTS: The Bland-Altman plots demonstrated that all three sequences show < 1.5 mm positional error. The measurement accuracy of Single Echo and Double Echo are prone to off-resonances, whereas Hadamard Encoding is immune to it. CONCLUSION: The developed phantom enabled the performance of objective measurements of the accuracy of different active tracking sequences. The proposed setup allows for objectively contrasting different methods for interventional procedures.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética Intervencionista/instrumentação , Imagem por Ressonância Magnética Intervencionista/métodos , Imagens de Fantasmas , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
16.
Org Biomol Chem ; 12(45): 9264-71, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25302765

RESUMO

The tert-alcohol and ionic liquid solvents in one molecule [mim-(t)OH][OMs] was immobilized on polystyrene and reported to be a highly efficient catalyst in aliphatic nucleophilic substitution using alkali metal salts. Herein, we investigated the catalytic activity of a new structurally modified polymer-supported tert-alcohol functionalized imidazolium salt catalyst in nucleophilic substitution of 2-(3-methanesulfonyloxypropyoxy)naphthalene as a model substrate with various metal nucleophiles. The tert-alcohol moiety of the ionic liquid with a hexyl chain distance from polystyrene had a better catalytic activity compared to the other resin which lacked an alkyl linker and tert-alcohol moiety. We found that the maximum [mim-(t)OH][OMs] loading had the best catalytic efficacy among the tested polystyrene-based ionic liquids (PSILs) in nucleophilic fluorination. The catalytic efficiency of the PS[him-(t)OH][OMs] as a phase transfer catalyst (PTC) was determined by carrying out various nucleophilic substitutions using the corresponding alkali metal salts from the third to sixth periodic in CH3CN or tert-BuOH media. The scope of this protocol with primary and secondary polar substrates containing many heteroatoms is also reported. This PS[him-(t)OH][OMs] catalyst not only enhances the reactivity of alkali metal salts and reduces the formation of by-products but also affords high yield with easy isolation.

17.
Environ Sci Technol ; 48(12): 7151-6, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24911921

RESUMO

Stainless steel (SS) can be an attractive material to create large electrodes for microbial bioelectrochemical systems (BESs), due to its low cost and high conductivity. However, poor biocompatibility limits its successful application today. Here we report a simple and effective method to make SS electrodes biocompatible by means of flame oxidation. Physicochemical characterization of electrode surface indicated that iron oxide nanoparticles (IONPs) were generated in situ on an SS felt surface by flame oxidation. IONPs-coating dramatically enhanced the biocompatibility of SS felt and consequently resulted in a robust electroactive biofilm formation at its surface in BESs. The maximum current densities reached at IONPs-coated SS felt electrodes were 16.5 times and 4.8 times higher than the untreated SS felts and carbon felts, respectively. Furthermore, the maximum current density achieved with the IONPs-coated SS felt (1.92 mA/cm(2), 27.42 mA/cm(3)) is one of the highest current densities reported thus far. These results demonstrate for the first time that flame oxidized SS felts could be a good alternative to carbon-based electrodes for achieving high current densities in BESs. Most importantly, high conductivity, excellent mechanical strength, strong chemical stability, large specific surface area, and comparatively low cost of flame oxidized SS felts offer exciting opportunities for scaling-up of the anodes for BESs.


Assuntos
Fontes de Energia Bioelétrica , Biofilmes/crescimento & desenvolvimento , Carbono/química , Eletricidade , Técnicas Eletroquímicas/métodos , Aço Inoxidável/química , Reatores Biológicos , Fibra de Carbono , Catálise , Eletrodos , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Oxirredução , Espectroscopia Fotoeletrônica , Análise Espectral Raman , Propriedades de Superfície
18.
Eur J Public Health ; 24(4): 561-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24850783

RESUMO

BACKGROUND: Exposure of young people to alcohol advertising is a risk factor for underage drinking. This study assessed youth exposure to television alcohol advertising in the UK, the Netherlands and Germany, from December 2010 to May 2011. METHODS: A negative binomial regression model predicted number of alcohol advertisements from the proportion of the television viewership in each age group. This allowed comparison of alcohol advertisement incidence for each youth age category relative to an adult reference category. RESULTS: In the UK, those aged 10-15 years were significantly more exposed to alcohol advertisements per viewing hour than adults aged ≥ 25 years [incidence rate ratio (IRR) = 1.11; 95% confidence interval (95% CI): 1.06, 1.18; P < 0.01]; in the Netherlands, those aged 13-19 years were more exposed per viewing hour than adults aged ≥ 20 years (IRR = 1.29; 95% CI: 1.19, 1.39; P < 0.01). Conversely, in Germany, those aged 10-15 years were less exposed to alcohol advertisements than adults aged ≥ 25 years (IRR = 0.79; 95% CI: 0.73, 0.85; P < 0.01). In each country, young children (aged 4-9 years in the UK and Germany, 6-12 years in the Netherlands) were less exposed than adults. CONCLUSION: Adolescents in the UK and the Netherlands, but not Germany, had higher exposure to television alcohol advertising relative to adults than would be expected from their television viewing. Further work across a wider range of countries is needed to understand the relationship between national policies and youth exposure to alcohol advertising on television.


Assuntos
Publicidade , Bebidas Alcoólicas , Adolescente , Adulto , Publicidade/estatística & dados numéricos , Fatores Etários , Bebidas Alcoólicas/estatística & dados numéricos , Criança , Pré-Escolar , Alemanha/epidemiologia , Humanos , Países Baixos/epidemiologia , Televisão/estatística & dados numéricos , Reino Unido/epidemiologia , Adulto Jovem
19.
J Minim Access Surg ; 10(3): 163-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25013337

RESUMO

Capsule endoscopy is a highly advanced, newer technology to look for small bowel diseases. But it has certain contraindications such as bowel narrowing, strictures that have to be ruled out on Barium studies or with computed tomography. We present a rare case of retention of endoscopic capsule even after ruling out stricture or bowel thickening on radiological imaging.

20.
Bioresour Technol ; 406: 130976, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38879056

RESUMO

This study aimed to understand the wastewater treatment and electricity generation performance besides the microbial communities of the integrated Hydroponics-Microbial Electrochemical Technology (iHydroMET) systems operated with water-saturated and water-unsaturated reactors. The organics removal was slightly higher in the water-unsaturated system (93 ± 4 %) than in the water-saturated system (87 ± 2 %). The total nitrogen removal and electric voltage were considerably higher in the water-saturated system (42 ± 5 %; 111 ± 8 V per reactor) than in the water-unsaturated system (18 ± 3 %; 95 ± 9 V per reactor). The enhanced organics and nitrogen removal and high voltage output in respective conditions were due to the dominance of polysaccharide-degrading aerobes (e.g., Pirellula), anammox bacteria (e.g., Anammoximicrobium), denitrifiers (e.g., Thauera and Rheinheimera), and electroactive microorganisms (e.g., Geobacter). The differential performance governed by distinct microbial communities under the tested conditions indicates that an appropriate balancing of water saturation and unsaturation in reactors is crucial to achieving optimum iHydroMET performance.

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