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1.
Zookeys ; 970: 51-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33024409

RESUMO

The greater wax moth, Galleria mellonella Linnaeus, is well known as a pest of honey bees and for the biodegradation of wax and polyethylene by their larvae. The genus Galleria has long been considered monotypic and found worldwide. A taxonomic study of the genus Galleria is presented based on morphological and molecular characters (COI, CAD, wg). A new species (Galleria similis Roh & Song, sp. nov.) is recognized on the Korean peninsula. The new species is superficially similar to G. mellonella but they can be separated by the structures of hindwing venation and male genitalia. Habitus photographs and illustrations of diagnostic characters are provided.

2.
Bioprocess Biosyst Eng ; 32(3): 389-95, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18751733

RESUMO

In a two-electrode system, freshwater sediment was used as a fuel to examine the relationship between current generation and organic matter consumption with different types of electrode. Sediment microbial fuel cells using porous electrodes showed a superior performance in terms of generating current when compared with the use of non-porous electrodes. The maximum current densities with thicker and thin porous electrodes were 45.4 and 37.6 mA m(-2), respectively, whereas the value with non-porous electrodes was 13.9 mA m(-2). The amount of organic matter removed correlated with the current produced. The redox potential in the anode area under closed-circuit conditions was +246.3 +/- 67.7 mV, while that under open-circuit conditions only reached -143.0 +/- 7.18 mV. This suggests that an application of this system in organic-rich sediment could provide environmental benefits such as decreasing organic matter and prohibiting methane emission in conjunction with electricity production via an anaerobic oxidation process.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Eletroquímica/instrumentação , Eletrodos , Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Chemosphere ; 186: 202-208, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28779595

RESUMO

A pilot-scale investigation of membrane-based aerobic digestion system dominated by endospore-forming bacteria was evaluated as one of the potential sludge treatment processes (STP). Most of the organic matter in the sludge was removed (90.1%) by the particular bacteria in the STP, which consisted of mixed liquor suspended solid (MLSS) contact reactor (MCR), MLSS oxidation reactor (MOR), and membrane bioreactor (MBR). The sludge was accumulated in the MBR without wasting, and then the effluent in STP was fed into the first step in water resource recovery facility (WRRF). According to the analysis of microbial communities in all reactors, various Bacillus species were present in the STP, mainly due to their intrinsic resistance to the extreme conditions. As the surviving Bacillus species might consume degraded microorganisms for their growth, these endospore-forming bacteria-based STP could be suitable for the sludge reduction when they operated for a long time.


Assuntos
Reatores Biológicos/microbiologia , Bactérias Formadoras de Endosporo/fisiologia , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Projetos Piloto
4.
Bioresour Technol ; 109: 308-11, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21724390

RESUMO

In this study, a novel algal biomass production method using a sediment microbial fuel cell (SMFC) system was assessed. Under the experimental conditions, CO(2) generation from the SMFC and its rate of increase were found to be dependent on the current generated from the SMFC. However, the CH(4) production rate from the SMFC was inhibited by the generation of current. When Chlorella vulgaris was inoculated into the cathode compartment of the SMFC and current was generated under 10 Ω resistance, biomass production from the anode compartment was observed to be closely associated with the rate of current generation from the SMFC. The experimental results demonstrate that 420 mg/L of algae (dry cell weight) was produced when the current from the SMFC reached 48.5 mA/m(2). Therefore, SMFC could provide a means for producing algal biomass via CO(2) generated by the oxidation of organics upon current generation.


Assuntos
Fontes de Energia Bioelétrica , Biomassa , Biotecnologia/métodos , Chlorella vulgaris/crescimento & desenvolvimento , Sedimentos Geológicos/microbiologia , Biotecnologia/instrumentação , Dióxido de Carbono/análise , Eletricidade , Metano/análise
5.
J Korean Neurosurg Soc ; 48(4): 354-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21113364

RESUMO

Partial thrombosis of giant aneurysms is not uncommon however, complete angiographic occlusion occurs less frequently. In the case of non-giant aneurysms, complete thrombosis and recanalization has been rarely reported. A 31-year-old man presented to the emergency department with sudden bursting headache. Brain computed tomography (CT) revealed diffuse subarachnoid hemorrhage on the left side. Both CT angiography (CTA) and digital subtraction angiography showed suspicion of small left anterior choroidal artery aneurysm. We performed surgical exploration. In the operation field, anterior choroidal artery aneurysm of 2 × 2 mm with broad neck and friable appearance was observed. Because we could not clip without sacrificing the anterior choroidal artery, we performed wrapping only. Follow up CTA after 7 months demonstrated 4 mm right internal carotid artery bifurcation aneurysm. The patient underwent aneurismal neck clipping. During the operation, 9 × 13 mm sized thrombosed aneurysm was detected and completely clipped. We initially thought this aneurysm to be a de novo aneurysm however, it was an aneurysm that had recanalized from a completely thrombosed aneurysm. This case report provides an insight into the potential for complete thrombosis and recanalization of non-giant aneurysms.

6.
Bioresour Technol ; 100(12): 3029-35, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19254835

RESUMO

The aim of this study was to evaluate limiting factors affecting electricity output from sediment microbial fuel cells (sediment MFCs). In laboratory tests, various factors likely to be encountered in field application were divided into controllable and uncontrollable ones. Based on the findings, it could be suggested that the sediment MFCs can be operated with an anode to cathode area ratio of at least 5:1 and at high external loads (1000 ohms) when the cathode is closely placed to the anode, though DO concentration at the cathode must be kept above 3 mg/l. Furthermore, no significant effect on current production over a prolonged period was observed within the sediment temperature range of 20-35 degrees C, but was negatively affected by lower temperatures (10 degrees C). These observations provide important factors with respect to the construction and operation of sediment MFCs at field sites, which will aid in maximizing electricity output.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Eletroquímica/instrumentação , Eletrodos , Sedimentos Geológicos/microbiologia , Desenho Assistido por Computador , Eletricidade , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Appl Microbiol Biotechnol ; 75(6): 1301-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17404727

RESUMO

This study shows the preparation and application of enzyme-nanofiber composites for long-term stable operation. The enzyme-nanofiber composite was prepared by coating an enzyme aggregate, the esterase from Rhizopus oryzae, on the surface of the nanofibers. After immobilization on the nanofiber, the apparent K ( m ) for the immobilized esterase was 1.48-fold higher than that of the free esterase, with values of 0.98 and 1.35 mM for the free and immobilized enzymes, respectively. It was found that enzyme-nanofiber was very stable, even when the fibers were shaken in glass vials, preserving 80% of the initial activity for 100 days. In addition, the enzyme-nanofiber composite was used repeatedly in 30 cycles of substrate hydrolysis and still remained active. Consequently, the esterase-nanofiber composite was employed within a continuous reactor system to evaluate its use in a long-term and stable continuous substrate hydrolysis reaction. It was found that the production of p-nitrophenol was stable for at least 400 h. This study demonstrates that the enzyme-nanofiber composite can be used in both repeated-batch mode and a continuous mode for a long-term stable operation.


Assuntos
Enzimas Imobilizadas/fisiologia , Esterases/fisiologia , Nanoestruturas , Reatores Biológicos , Estabilidade Enzimática , Maleatos , Poliestirenos , Rhizopus/enzimologia
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