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Sample records for combined plfa dgge

  1. Long-term impact of farm management and crops on soil microorganisms assessed by combined DGGE and PLFA analyses

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    Fabio eStagnari

    2014-12-01

    Full Text Available In the present study, long-term organic and conventional managements were compared at the experimental field of Monsampolo del Tronto (Marche region, Italy with the aim of investigating soil chemical fertility and microbial community structure. A polyphasic approach, combining soil fertility indicators with microbiological analyses (plate counts, PCR-denaturing gradient gel electrophoresis [DGGE] and phospholipid fatty acid analysis [PLFA] was applied. Organic matter, N as well as some important macro and micronutrients (K, P, Mg, Mn, Cu and Zn for crop growth, were more available under organic management. Bacterial counts were higher in organic management. A significant influence of management system and management x crop interaction was observed for total mesophilic bacteria, nitrogen fixing bacteria and actinobacteria. Interestingly, cultivable fungi were not detected in all analyzed samples. PLFA biomass was higher in the organic and Gram positive bacteria dominated the microbial community in both systems. Even if fungal biomass was higher in organic management, fungal PCR-DGGE fingerprinting revealed that the two systems were very similar in terms of fungal species suggesting that 10 years were not enough to establish a new dynamic equilibrium among ecosystem components. A better knowledge of soil biota and in particular of fungal community structure will be useful for the development of sustainable management strategies.

  2. Soil microbial community structure in diverse land use systems:A comparative study using Biolog,DGGE,and PLFA analyses

    Institute of Scientific and Technical Information of China (English)

    XUE Dong; YAO Huai-Ying; GE De-Yong; HUANG Chang-Yong

    2008-01-01

    Biolog,16S rRNA gene denaturing gradient gel electrophoresis (DGGE),and phospholipid fatty acid (PLFA) analyses were used to assess soil microbial community characteristics in a chronosequence of tea garden systems (8-,50-,and 90year-old tea gardens),an adjacent wasteland,and a 90-year-old forest.Biolog analysis showed that the average well color development (AWCD) of all carbon sources and the functional diversity based on the Shannon index decreased (P<0.05)in the following order:wasteland>forest>tea garden.For the DGGE analysis,the genetic diversity based on the Shannon index was significantly lower in the tea garden soils than in the wasteland.However,compared to the 90-year-old forest,the tea garden soils showed significantly higher genetic diversity.PLFA analysis showed that the ratio of Gram positive bacteria to Gram negative bacteria was significantly higher in the tea garden soils than in the wasteland,and the highest value was found in the 90-year-old forest.Both the fungal PLFA and the ratio of fungi to bacteria were significantly higher in the three tea garden soils than in the wasteland and forest,indicating that fungal PLFA was significantly affected by land-use change.Based on cluster analysis of the soil microbial community structure,all three analytical methods showed that land-use change had a greater effect on soil microbial community structure than tea garden age.

  3. Characterization of microbial communities in a pilot-scale constructed wetland using PLFA and PCR-DGGE analyses.

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    Jin, Guang; Kelley, Timothy R

    2007-09-01

    Phospholipid fatty acid (PLFA) analysis and 16S ribosomal DNA polymerase chain reaction amplification-denaturing gradient gel electrophoresis (PCR-DGGE) were used to determine microbial communities and predominant microbial populations in water samples collected from a pilot-scale constructed wetland system. This pilot-scale constructed wetland system consists of three types: subsurface-flow (SSF), surface-flow (SF) and a floating aquatic plant (FAP) system. Analysis of PLFA profiles indicated primarily eukaryotic organisms, including fungi, protozoa, and diatoms were observed in all three wetland systems. Biomarkers for Gram-negative bacteria were also detected in all samples analyzed while low proportions of biomarkers for Gram-positive bacteria were observed. Biomass content (total PFLA/sample) was highest in water samples collected from both SF and FAP system while highest metabolic activity was observed in FAP system. This is consistent with the observed highest metal removal rate in FAP system. Sequence analysis of the predominant PCR-DGGE DNA fragments showed 0.92 to 0.99 similarity indices to Beta-proteobacteria, Flavobacterium sp. GOBB3-206, Flexibacter-Cytophaga-Bacteroides group, and Gram-positive bacteria. Results suggest diverse microbial communities including microorganisms that may significantly contribute to biogeochemical elemental cycles.

  4. Utilization of low molecular weight organics by soil microorganisms: combination of 13C-labelling with PLFA analysis

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    Gunina, Anna; Dippold, Michaela; Kuzyakov, Yakov

    2014-05-01

    Microbial metabolisation is the main transformation pathway of low molecular weight organic substances (LMWOS), but detailed knowledge concerning the fate of LMWOS in soils is strongly limited. Considering that various LMWOS classes enter biochemical cycles at different steps, we hypothesise that the percentage of their LMWOS-Carbon (C) used for microbial biomass (MB) production and consequently medium-term stabilisation in soil is different. We traced the three main groups of LMWOS: amino acids, sugars and carboxylic acids, by uniformly labelled 13C-alanine, -glutamate, -glucose, -ribose, -acetate and -palmitate. Incorporation of 13C from these LMWOS into MB (fumigation-extraction method) and into phospholipid fatty acids (PLFAs) (Bligh-Dyer extraction, purification and GC-C-IRMS measurement) was investigated under field conditions 3 d and 10 d after LMWOS application. The activity of microbial utilization of LMWOS for cell membrane construction was estimated by replacement of PLFA-C with 13C. Decomposition of LMWOS-C comprised 20-65% of the total label, whereas incorporation of 13C into MB amounted to 20-50% of initially applied 13C on day three and was reduced to 5-30% on day 10. Incorporation of 13C-labelled LMWOS into MB followed the trend sugars > carboxylic acids > amino acids. Differences in microbial utilisation between LMWOS were observed mainly at day 10. Thus, instead of initial rapid uptake, further metabolism within microbial cells accounts for the individual fate of C from different LMWOS in soils. Incorporation of 13C from each LMWOS into each PLFA occurred, which reflects the ubiquitous ability of all functional microbial groups for LMWOS utilization. The preferential incorporation of palmitate can be attributed to its role as a direct precursor for many fatty acids (FAs) and PLFA formation. Higher incorporation of alanine and glucose compared to glutamate, ribose and acetate reflect the preferential use of glycolysis-derived substances in the FAs

  5. Microbial Pollution Tracking of Dairy Farm with a Combined PCR-DGGE and qPCR Approach.

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    Xi, Xiaoxia; Zhang, Jiachao; Kwok, Laiyu; Huo, Dongxue; Feng, Shuzhen; Zhang, Heping; Sun, Tiansong

    2015-12-01

    Animal husbandry is a traditional industry with regional characteristic in the Inner Mongolia of China. Recent years, animal breeding has been one of the main pollution sources in this area, followed by domestic sewage and industrial wastewater. The pollution of livestock farm feces may accelerate the development of pathogens and antibiotic resistance genes which pose health risks to humans and animals. In present research, culture-independent molecular ecological methods based on DGGE combined with qPCR were used to investigate the pollution to surrounding environment with different degrees of livestock farm. The cluster analysis of DGGE patterns showed that the livestock farm feces from point pollution source flowed with wastewater discharge has resulted in an impacted range of at least 3000 m, but it did not cause pollution to residential water delivered from upstream of sewage drain outlet. qPCR results revealed that 5 common pathogens (Escherichia coli, Enterococcus, Staphylococcus aureus, Shigella, and Salmonella) presented decreased trend as the sampled distance from point pollution source increased. Also, qPCR assays of 10 common antibiotic resistance genes (tetO, tetL, rpp, rpoB, sul2, sulA, floR, yidY, mphA, and ermC) which cause resistance to tetracycline, rifampicin, fluoroquinolone, quinolone, and erythromycin have been found in the environmental samples. This study clearly indicates the livestock farm discharge pollutants contaminated to the surrounding environment. Our data have provided important information to pollution control in the future.

  6. Microbial diversity in lake sediments detected by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    Xinqing ZHAO; Liuyan YANG; Can CHEN; Lin XIAO; Lijuan JIANG; Zhe MA; Haowei ZHU; Zhenyang YU; Daqiang YIN

    2008-01-01

    In this study,PCR-denaturing gradient gel electrophoresis (DGGE) was applied to analyze the microbial communities in lake sediments from Lake Xuanwu,Lake Mochou in Nanjing and Lake Taihu in Wuxi.Sediment samples from seven locations in three lakes were collected and their genomic DNAs were extracted.The DNA yields of the sediments of Lake Xuanwu and Lake Mochou were high (10 μg/g),while that of sediments in Lake Taihu was relatively low.After DNA purification,the 16S rDNA genes (V3 to V5 region) were amplified and the amplified DNA fragments were separated by parallel DGGE.The DGGE profiles showed that there were five common bands in all the lake sediment samples indicating that there were similarities among the populations of microorganisms in all the lake sediments.The DGGE profiles of Lake Xuanwu and Lake Mochou were similar and about 20 types of micro-organisms were identified in the sediment samples of both lakes.These results suggest that the sediment samples of these two city lakes (Xuanwu,Mochou) have similar microbial communities.However,the DGGE profiles of sediment samples in Lake Taihu were significantly differ-ent from these two lakes.Furthermore,the DGGE pro-files of sediment samples in different locations in Lake Taihu were also different,suggesting that the microbial communities in Lake Taihu are more diversified than those in Lake Xuanwu and Lake Mochou.The differences in microbial diversity may be caused by the different environmental conditions,such as redox potential,pH,and the concentrations of organic matters.Seven major bands of 16S rDNA genes fragments from the DGGE profiles of sediment samples were further re-amplified and sequenced.The results of sequencing analysis indicate that five sequences shared 99%-100% homology with known sequences (Bacillus and Brevibacillus,uncultured bacteria),while the other two sequences shared 93%-96% homology with known sequences (Acinetobacter,and Bacillus).The study shows that the PCR-DGGE tech

  7. 牙周牙髓联合病变菌群的PCR-DGGE分析%Bacterial analysis of combined periodontal-endodontic lesions using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE)

    Institute of Scientific and Technical Information of China (English)

    夏明慧; 亓庆国

    2012-01-01

    目的 利用变性梯度凝胶电泳(DGGE)技术观察牙周牙髓联合病变患牙牙周组织和根管中原始菌群分布状况及其异同,并通过克隆测序技术来试图探讨两部位可能存在的优势菌.方法 从13例牙周牙髓联合病变患牙分别采集患牙根尖1/3处牙周细菌和根管牙髓细菌,提取细菌总DNA,扩增16S rRNA基因可变区,再进行变性梯度凝胶电泳.应用SPSS17.0软件和Quantity One软件对DGGE图谱菌种条带进行统计学分析和聚类分析.对DGGE凝胶中有代表性的条带进行回收和克隆测序.结果 两取菌部位的菌种条带数间有明显的统计学差异(P<0.01),但二者之间无正相关性.二者间的相似系数为13.1% ~62.5%.牙周牙髓联合病变患牙根尖区1/3处牙周菌属可能有弯曲菌属(Campylobacter)、梭杆菌属(Fusobacterium)、奈瑟菌属(Neisseria)等,该处对应根管中菌属可能有优杆菌属(Mogibacterium)、棒状杆菌属(Corynebacterium)、放线菌属(Actinomyces)等.结论 牙周牙髓联合病变(牙周来源)中牙周组织和邻近根管牙髓组织中菌种在数目和结构上有明显不同.该病变牙周组织和根管中可能存在目前尚未被认知的优势菌种.%Objective To compare the bacterial community profiles present in periodontium and root canals of the same tooth diagnosed as combined periodontal-endodontic lesions by using denaturing gradient gel electrophoresis (DGGE).Methods Samples were collected from 13 extracted teeth with advanced periodontitis,endodontic samples from root tip 1/3 root canal,and periodontal samples from the corresponding neighboring periodontium.Genomic DNA was collected for the following universal bacterial primersPCR.The PCR products were then loaded on the DGGE gels to gain separate bands.The typical DGGE bands were excised,PCR-cloned and sequenced.Results The number of bands,which was indicative of the number of bacterial species,was compared intra-group (periodontal and

  8. PLFA profiles of drinking water biofilters with different acetate and glucose loadings.

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    Yu, Xin; Shi, Xu; Wei, Bo; Ye, Lin; Zhang, Shuting

    2009-08-01

    The biofilters fed with acetate or glucose and their phospholipid fatty acid (PLFA) profiles were investigated to observe the impact of organic matter concentrations on the microbial community structure in the drinking water production system. PLFA markers for bacteria were predominant in all of the biofilters and made up over half of the total PLFA content. PLFA diversity was compared and the biofilters fed with glucose had higher diversity. The Shannon-Wiener (or sometimes known as just Shannon diversity index) indices in the biofilters fed with acetate were from 0.68 to 0.97, while the indices in the biofilters fed with glucose were from 0.95 to 1.25. Principle components analysis showed that carbon sources and media depth were responsible for 68 and 17% of the total PLFA variance, respectively. The results indicated that PLFA analysis could be useful in illustrating microbial community structure in drinking water bioreactors, and microbial community structure was impacted by carbon substrates.

  9. Application of nested PCR-DGGE (denaturing gradient gel electrophoresis) for the analysis of ciliate communities in soils.

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    Shimano, Satoshi; Sambe, Mitsuo; Kasahara, Yasuhiro

    2012-01-01

    Ciliates play important roles as prey and predators in ecosystems. Changes in the ciliate community can affect the composition and population of microfauna and microflora in ecosystems. To investigate the structure of ciliate communities, we developed a nested PCR-DGGE method, which combines a universal eukaryotic-specific primer set in the first PCR step with a ciliate-specific primer set in the second PCR step, to amplify 18S rRNA genes from ciliates. The 300 bp DGGE fragments generated more bands on the gel than the 600 bp DGGE fragments. Prior to bead beating, DNA extraction of ciliates from soil samples was optimized with a combination of freeze-thaw cycles and ultrasonication. We applied this nested PCR-DGGE method to agricultural soils amended with 0, 120, 300, and 600 t ha⁻¹ year⁻¹ of livestock slurry. The results from the DGGE profiles and principal component analysis (PCA) revealed that the supplement of slurry to soils influenced the ciliate communities. From phylogenetic analysis, 108 DGGE bands were assigned to six classes, which included Spirotrichea and Colpodea, of the subphylum Intramacronucleata, and one class of the subphylum Postciliodesmatophora. These results indicated that a wide variety of taxonomic groups were detected by DGGE profiling. Thus, the nested PCR-DGGE method described here could clearly differentiate between ciliate communities within soil samples and allowed for the phylogenetic identification of these ciliates at the class level.

  10. Determination of microbial carbon sources and cycling during remediation of petroleum hydrocarbon impacted soil using natural abundance (14)C analysis of PLFA.

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    Cowie, Benjamin R; Greenberg, Bruce M; Slater, Gregory F

    2010-04-01

    In a petroleum impacted land-farm soil in Sarnia, Ontario, compound-specific natural abundance radiocarbon analysis identified biodegradation by the soil microbial community as a major pathway for hydrocarbon removal in a novel remediation system. During remediation of contaminated soils by a plant growth promoting rhizobacteria enhanced phytoremediation system (PEPS), the measured Delta(14)C of phospholipid fatty acid (PLFA) biomarkers ranged from -793 per thousand to -897 per thousand, directly demonstrating microbial uptake and utilization of petroleum hydrocarbons (Delta(14)C(PHC) = -1000 per thousand). Isotopic mass balance indicated that more than 80% of microbial PLFA carbon was derived from petroleum hydrocarbons (PHC) and a maximum of 20% was obtained from metabolism of more modern carbon sources. These PLFA from the contaminated soils were the most (14)C-depleted biomarkers ever measured for an in situ environmental system, and this study demonstrated that the microbial community in this soil was subsisting primarily on petroleum hydrocarbons. In contrast, the microbial community in a nearby uncontaminated control soil maintained a more modern Delta(14)C signature than total organic carbon (Delta(14)C(PLFA) = +36 per thousand to -147 per thousand, Delta(14)C(TOC) = -148 per thousand), indicating preferential consumption of the most modern plant-derived fraction of soil organic carbon. Measurements of delta(13)C and Delta(14)C of soil CO(2) additionally demonstrated that mineralization of PHC contributed to soil CO(2) at the contaminated site. The CO(2) in the uncontaminated control soil exhibited substantially more modern Delta(14)C values, and lower soil CO(2) concentrations than the contaminated soils, suggesting increased rates of soil respiration in the contaminated soils. In combination, these results demonstrated that biodegradation in the soil microbial community was a primary pathway of petroleum hydrocarbon removal in the PEPS system. This study

  11. Microbial utilization of sugars in soil assessed by position-specific labeling and compound-specific 13C-PLFA-analysis

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    Apostel, Carolin; Dippold, Michaela; Glaser, Bruno; Kuzyakov, Yakov

    2014-05-01

    For the transformation of low molecular weight organic substances (LMWOS) in soil, which is an important process in the turnover of organic matter, microbial utilization is one of the most important processes. Position-specific labeling combined with compound-specific 13C-PLFA-analysis allows a closer look on the mechanisms of LMWOS transformation in soil. We assessed short- (3 and 10 days) and long-term (half year) transformations of monosaccharides by adding position-specifically 13C labeled glucose and ribose to soil in a field experiment conducted on an agriculturally used luvisol located in north-western Bavaria. We quantified the microbial utilization of the different functional groups by 13C-analysis of microbial biomass with the chloroform-fumigation-extraction method (CFE). 13C-PLFA analysis enabled us to distinguish individual microbial groups and compare their C-utilization. Preferential degradation of glucoses C-3 and C-4 respectively C-1 position enabled differentiation between the two main hexose metabolic pathways - glycolysis and the pentose phosphate pathway. Microbial groups revealed different incorporation of specific C positions into their PLFA. The highest incorporation was reached by the prokaryotic gram- negative groups. The application of position-specifically labeled substances, coupled with compound-specific 13C-PLFA analysis opens a new way to investigate the microbial transformations of LMWOS in soil. Observing single C atoms and their utilization by specific microbial groups allow conclusions about the mechanisms and kinetics of microbial utilization and interaction between these groups and therefore will improve our understanding of soil carbon fluxes.

  12. Analysis of phospholipid fatty acids (PLFA) to characterize microbial communities in aquifers

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    Green, Christopher T.; Scow, Kate M.

    This paper reviews published applications of lipid-based biochemical techniques for characterizing microbial communities in aquifers and other deep subsurface habitats. These techniques, such as phospholipid fatty acid (PLFA) analysis, can provide information on a variety of microbial characteristics, such as biomass, physiology, taxonomic and functional identity, and overall community composition. In addition, multivariate statistical analysis of lipid data can relate spatial or temporal changes in microbial communities to environmental factors. The use of lipid-based techniques in the study of groundwater microbiology is advantageous because they do not require culturing and can provide quantitative data on entire communities. However, combined effects of physiological and phylogenetic changes on the lipid composition of a community can confound interpretation of the data, and many questions remain about the validity of various lipid techniques. Despite these caveats, lipid-based research has begun to show trends in community composition in contaminated and pristine aquifers that contribute to our understanding of groundwater microbial ecology and have potential for use in optimization of bioremediation of groundwater pollutants. Résumé Ce papier passe en revue les applications des techniques biochimiques basées sur les lipides pour caractériser les communautés microbiennes présentes dans les aquifères et dans les autres habitats souterrains profonds. Ces techniques, telles que l'analyse des acides gras phospholipidiques (PLFA), peuvent fournir des informations sur un ensemble de caractères microbiens, tels que la biomasse, la physiologie, l'identité taxonomique et fonctionnelle, et surtout la composition de la communauté. En outre, l'analyse statistique multivariée des données sur les lipides peut établir les liens entre des changements spatiaux ou temporels dans la communauté microbienne et des facteurs environnementaux. L'utilisation des

  13. Characterisation of prototype Nurmi cultures using culture-based microbiological techniques and PCR-DGGE.

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    Waters, Sinéad M; Murphy, Richard A; Power, Ronan F G

    2006-08-01

    Undefined Nurmi-type cultures (NTCs) have been used successfully to prevent salmonella colonisation in poultry for decades. Such cultures are derived from the caecal contents of specific-pathogen-free birds and are administered via drinking water or spray application onto eggs in the hatchery. These cultures consist of many non-culturable and obligately anaerobic bacteria. Due to their undefined nature it is difficult to obtain approval from regulatory agencies to use these preparations as direct fed microbials for poultry. In this study, 10 batches of prototype NTCs were produced using an identical protocol over a period of 2 years. Traditional microbiological techniques and a molecular culture-independent methodology, polymerase chain reaction combined with denaturing gradient gel electrophoresis (PCR-DGGE), were applied to characterise these cultures and also to examine if the constituents of the NTCs were identical. Culture-dependent analysis of these cultures included plating on a variety of selective and semi-selective agars, examination of colony morphology, Gram-staining and a series of biochemical tests (API, BioMerieux, France). Two sets of PCR-DGGE studies were performed. These involved the amplification of universal and subsequently lactic acid bacteria (LAB)-specific hypervariable regions of a 16S rRNA gene by PCR. Resultant amplicons were subjected to DGGE. Sequence analysis was performed on subsequent bands present in resultant DGGE profiles using the Basic Local Alignment Search Tool (BLAST). Microbiological culturing techniques tended to isolate common probiotic bacterial species from the genera Lactobacillus, Lactococcus, Bifidobacterium, Enterococcus, Clostridium, Escherichia, Pediococcus and Enterobacterium as well as members of the genera, Actinomyces, Bacteroides, Propionibacterium, Capnocytophaga, Proteus, and Klebsiella. Bacteroides, Enterococcus, Escherichia, Brevibacterium, Klebsiella, Lactobacillus, Clostridium, Bacillus, Eubacterium

  14. Analysis of unculturable bacterial communities in tea orchard soils based on nested PCR-DGGE.

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    Zhao, Juan; Wu, Xiaobing; Nie, Chuanpeng; Wu, Ting; Dai, Wanhong; Liu, Hui; Yang, Ruyi

    2012-05-01

    The bacterial communities in the soils from tea orchards and their adjacent wasteland in Anhui Province, China were analysed by nested PCR-DGGE technique combined with sequencing. DGGE profiles revealed that the DGGE patterns of different soils were similar to each other and the most intensely bands appeared in all lanes. The bacterial genetic diversity index of tea orchard soils was lower than that of wasteland. For the tea orchard soils, Shannon's diversity index decreased in the order: 45-year-old tea orchard >25-year-old tea orchard >7-year-old tea orchard >70-year-old tea orchard. The analysis of 16S rRNA gene sequences indicated that the fragments belong to Proteobacteria, Acidobacteria, TM7, Cyanobacteria and Firmicutes. A comprehensive analysis of the bacterial community structure in the tea orchard soils indicated the bacterial community was dominantly composed of Acidobacteria, followed by Proteobacteria (Gamma and Alpha), Firmicutes, Cyanobacteria and candidate division TM7. The RDA combined with UPGMA clustering analysis showed that the more similar the environmental variables were, the more similar the bacterial community structures in tea orchard soils were.

  15. Functional diversity of microbial communities in pristine aquifers inferred by PLFA- and sequencing-based approaches

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    Schwab, Valérie F.; Herrmann, Martina; Roth, Vanessa-Nina; Gleixner, Gerd; Lehmann, Robert; Pohnert, Georg; Trumbore, Susan; Küsel, Kirsten; Totsche, Kai U.

    2017-05-01

    Microorganisms in groundwater play an important role in aquifer biogeochemical cycles and water quality. However, the mechanisms linking the functional diversity of microbial populations and the groundwater physico-chemistry are still not well understood due to the complexity of interactions between surface and subsurface. Within the framework of Hainich (north-western Thuringia, central Germany) Critical Zone Exploratory of the Collaborative Research Centre AquaDiva, we used the relative abundances of phospholipid-derived fatty acids (PLFAs) to link specific biochemical markers within the microbial communities to the spatio-temporal changes of the groundwater physico-chemistry. The functional diversities of the microbial communities were mainly correlated with groundwater chemistry, including dissolved O2, Fet and NH4+ concentrations. Abundances of PLFAs derived from eukaryotes and potential nitrite-oxidizing bacteria (11Me16:0 as biomarker for Nitrospira moscoviensis) were high at sites with elevated O2 concentration where groundwater recharge supplies bioavailable substrates. In anoxic groundwaters more rich in Fet, PLFAs abundant in sulfate-reducing bacteria (SRB), iron-reducing bacteria and fungi increased with Fet and HCO3- concentrations, suggesting the occurrence of active iron reduction and the possible role of fungi in meditating iron solubilization and transport in those aquifer domains. In more NH4+-rich anoxic groundwaters, anammox bacteria and SRB-derived PLFAs increased with NH4+ concentration, further evidencing the dependence of the anammox process on ammonium concentration and potential links between SRB and anammox bacteria. Additional support of the PLFA-based bacterial communities was found in DNA- and RNA-based Illumina MiSeq amplicon sequencing of bacterial 16S rRNA genes, which showed high predominance of nitrite-oxidizing bacteria Nitrospira, e.g. Nitrospira moscoviensis, in oxic aquifer zones and of anammox bacteria in more NH4+-rich

  16. Comparison of PCR-DGGE and Nested-PCR-DGGE Approach for Ammonia Oxidizers Monitoring in Membrane Bioreactors’ Activated Sludge

    Directory of Open Access Journals (Sweden)

    Ziembińska-Buczyńska Aleksandra

    2014-12-01

    Full Text Available Nitritation, the first stage of ammonia removal process is known to be limiting for total process performance. Ammonia oxidizing bacteria (AOB which perform this process are obligatory activated sludge habitants, a mixture consisting of Bacteria, Protozoa and Metazoa used for biological wastewater treatment. Due to this fact they are an interesting bacterial group, from both the technological and ecological point of view. AOB changeability and biodiversity analyses both in wastewater treatment plants and lab-scale reactors are performed on the basis of 16S rRNA gene sequences using PCR-DGGE (Polymerase Chain Reaction – Denaturing Gradient Gel Electrophoresis as a molecular biology tool. AOB researches are usually led with nested PCR. Because the application of nested PCR is laborious and time consuming, we have attempted to check the possibility of using only first PCR round to obtain DGGE fingerprinting of microbial communities. In this work we are comparing the nested and non-nested PCR-DGGE monitoring of an AOB community and presenting advantages and disadvantages of both methods used. The experiment revealed that PCR technique is a very sensitive tool for the amplification of even a minute amount of DNA sample. But in the case of nested-PCR, the sensitivity is higher and the template amount could be even smaller. The nested PCR-DGGE seems to be a better tool for AOB community monitoring and complexity research in activated sludge, despite shorter fragments of DNA amplification which seems to be a disadvantage in the case of bacteria identification. It is recommended that the sort of analysis approach should be chosen according to the aim of the study: nested-PCR-DGGE for community complexity analysis, while PCR-DGGE for identification of the dominant bacteria.

  17. Assessing microbial utilization of free versus sorbed Alanine by using position-specific 13C labeling and 13C-PLFA analysis

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    Herschbach, Jennifer; Apostel, Carolin; Spielvogel, Sandra; Kuzyakov, Yakov; Dippold, Michaela

    2016-04-01

    Microbial utilization is a key transformation process of soil organic matter (SOM). Sorption of low molecular weight organic substances (LMWOS) to soil mineral surfaces blocks or delays microbial uptake and therefore mineralization of LMWOS to CO2, as well as all other biochemical transformations. We used position-specific labeling, a tool of isotope applications novel to soil science, combined with 13C-phospholipid fatty acid (PLFA) analysis, to assess microbial utilization of sorbed and non-sorbed Alanine in soil. Alanine has various functional groups enabling different sorption mechanisms via its positive charge (e.g. to clay minerals by cation exchange), as well as via its negative charge (e.g. to iron oxides by ligand exchange). To assess changes in the transformation pathways caused by sorption, we added uniformly and position-specifically 13C and 14C labeled Alanine to the Ap of a loamy Luvisol in a short-term (10 days) incubation experiment. To allow for sorption of the tracer solution to an aliquot of this soil, microbial activity was minimized in this subsample by sterilizing the soil by γ-radiation. After shaking, the remaining solutions were filtered and the non-sorbed Alanine was removed with Millipore water and then added to non-sterilized soil. For the free Alanine treatment, solutions with Alanine of similar amount and isotopic composition were prepared, added to the soil and incubated as well. The respired CO2 was trapped in NaOH and its 14C-activity was determined at increasing times intervals. Microbial utilization of Alanine's individual C positions was evaluated in distinct microbial groups classified by 13C-PLFA analysis. Sorption to soil minerals delayed respiration to CO2 and reduced initial respiration rate by 80%. Irrespective of sorption, the highest amount was respired from the carboxylic position (C-1), whereas the amino-bound (C-2) and the methylic position (C-3) were preferentially incorporated into PLFA of microorganisms due to the

  18. Investigation of petroleum residues and microbial PLFA in Barataria Bay sediments one year after the Deepwater Horizon oil spill

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    Clay, S.; Zimmerman, A. R.; Mahmoudi, N.; Silliman, B. R.; Slater, G. F.

    2012-12-01

    The Deepwater Horizon spill released crude oil into the Gulf of Mexico over a period of 3 months in 2010. Barataria Bay, Louisiana was among the most heavily impacted and extensively oil-contaminated coastlines. Studies conducted in the marshes show significant ecological and geologic effects from oil residues that reached the bay. Observation of the presence of an oil sheen associated with sediment disturbance raised the question as to whether petroleum residues were also present in the sediments of Barataria Bay. In order to address this question, six sediment cores were collected from non-oiled (#1 & 2) and oiled (#3-6) portions of Barataria Bay approximately one year after the Deepwater Horizon oil spill. Concentrations of n-alkanes, unresolved complex material (UCM) and polycyclic aromatic hydrocarbon (PAH) were determined in these upper sediments. In addition, concentrations of phospholipid fatty acids (PLFA) were determined to assess variations in microbial community abundance. Alkane concentrations ranged from 134 to 747 ng/g with chain lengths from C12 to C35. Most cores showed an odd over even preference (carbon preference index of 1.2 to 4.3) with highest concentrations of long chain compounds between C24 and C35 (average chain length 29 to 39), consistent with a terrestrial carbon source such as plant waxes. Core #6 however, in the southwest portion of the bay, had the lowest concentrations of alkanes, and shorter n-alkane chain lengths overall. Despite this difference, the core maintains a relatively high carbon preference index and average chain length compared to that which would be expected from oil contaminated sediments. Measured PAH concentrations were highly variable ranging from undetectable to 436 ng/g. These values are several orders of magnitude lower than what is generally seen in highly contaminated sediments. Further, UCM concentrations were negligible in the cores from the oiled regions. These findings suggest only a minimal presence of

  19. Diversity of bacterial population of table olives assessed by PCR-DGGE analysis.

    Science.gov (United States)

    Randazzo, Cinzia L; Ribbera, Angela; Pitino, Iole; Romeo, Flora V; Caggia, Cinzia

    2012-10-01

    Nocellara Etnea and Geracese table olives are produced according to traditional process, in which lactic acid bacteria (LAB) and yeasts are the dominant microorganisms. With the aim to evaluate the effect of selected starter cultures on dynamics of bacterial population during fermentation and on growth/survival of Listeria spp. artificially inoculated into the olive brine, a polyphasic approach based on the combination of culturing and PCR-DGGE analysis was applied. Plating results showed a different concentration of the major bacterial groups considered among cultivars and the beneficial effect of LAB starters, which clearly inhibited Enterobacteriaceae. Moreover, results indicated that the brine conditions applied did not support the growth/survival of Listeria monocytogenes strain, artificially inoculated, highlighting the importance of selecting right fermentation parameters for assuring microbiological safety of the final products. Comparison of DGGE profile of Nocellara Etnea and Geracese table olives, displayed a great difference among cultivars, revealing a wide biodiversity within Lactobacillus population during Geracese olives fermentation. Based on cloning and sequencing of the most dominant amplicons, the presence, among others, of Lactobacillus paracollinoides and Lactobacillus coryniformis in Geracese table olives was revealed in table olives for the first time.

  20. Application of a novel Paenibacillus-specific PCR-DGGE method and sequence analysis to assess the diversity of Paenibacillus spp. in the maize rhizosphere.

    NARCIS (Netherlands)

    da Silva, Katia Regina Araujo; Falcao Salles, Joana; Seldin, Lucy; van Elsas, Jan

    2003-01-01

    In this study, a Paenibacillus-specific PCR system, based on the specific primer PAEN515F in combination with bacterial primer R1401, was tested and used to amplify specific fragments of the 16S rRNA gene from rhizosphere DNA. The amplicons were used in a second (semi-nested) PCR for DGGE, in which

  1. Application of a novel Paenibacillus-specific PCR-DGGE method and sequence analysis to assess the diversity of Paenibacillus spp. in the maize rhizosphere

    NARCIS (Netherlands)

    Silva, da K.R.A.; Salles, J.F.; Seldin, L.; Elsas, van J.D.

    2003-01-01

    In this study, a Paenibacillus-specific PCR system, based on the specific primer PAEN515F in combination with bacterial primer R1401, was tested and used to amplify specific fragments of the 16S rRNA gene from rhizosphere DNA. The amplicons were used in a second (semi-nested) PCR for DGGE, in which

  2. Analysis of endophytic bacterial communities of potato by plating and denaturing gradient gel electrophoresis (DGGE) of 16S rDNA based PCR fragments

    NARCIS (Netherlands)

    Garbeva, P.; Overbeek, van L.S.; Vuurde, van J.W.L.; Elsas, van J.D.

    2001-01-01

    The diversity of endophytic bacterial populations of potato (Solanum tuberosum cv Desiree) was assessed using a combination of dilution plating of plant macerates followed by isolation and characterization of isolates, and direct PCR-DGGE on the basis of DNA extracted from plants. The culturable end

  3. Comparison of bacterial community structures in two systems of a sewage treatment plant using PCR-DGGE analysis

    Institute of Scientific and Technical Information of China (English)

    Abd El-Latif Hesham; Rong Qi; MinYang

    2011-01-01

    The combination of PCR amplification of 16S rRNA genes with denaturing gradient gel electrophoresis (DGGE) analysis was used to reveal the compositions and dynamics of bacterial communities in a sewage treatment plant with two systems,i.e.,an anoxicanaerobic-aerobic system (inverted A2O) and an anaerobic-anoxic-aerobic one (conventional A2O) over a period from February to July 2009,during which both systems experienced serious sludge bulking problems.The DGGE patterns showed that there were many common bands in both systems,suggesting the high similarity of bacterial communities of the two systems.Meanwhile,the moving window correlation analysis showed that the two systems experienced different microbial community structure changes during the period,which might be related with the different situations of the occurrence and disappearance of sludge bulking,as being reflected by sludge volume index (SVI) values.Major bands of DGGE patterns of sludge samples were further sequenced.Phylogenetic affiliation indicated that the majority of the sequences obtained were affiliated with Actinobacteria,Firmicutes,Bacteroidetes/Chlorobi group and α- and β-Proteobacteria.Two sequences showed high similarities to typical filamentous bacteria Microthrix parvicella and Nostocoida limicola I,indicating that these bacterial species have been involved in the sludge bulking problems.

  4. Identification of Biodegradation Pathways in a Multi-Process Phytoremediation System (MPPS) Using Natural Abundance 14C Analysis of PLFA

    Science.gov (United States)

    Cowie, B. R.; Greenberg, B. M.; Slater, G. F.

    2008-12-01

    Optimizing remediation of petroleum-contaminated soils requires thorough understanding of the mechanisms and pathways involved in a proposed remediation system. In many engineered and natural attenuation systems, multiple degradation pathways may contribute to observed contaminant mass losses. In this study, biodegradation in the soil microbial community was identified as a major pathway for petroleum hydrocarbon removal in a Multi-Process Phytoremediation System (MPPS) using natural abundance 14C analysis of Phospholipid Fatty Acids (PLFA). In contaminated soils, PLFA were depleted in Δ14C to less than -800‰, directly demonstrating microbial uptake and utilization of petroleum derived carbon (Δ14C = -992‰) during bioremediation. Mass balance indicated that more than 80% of microbial carbon was derived from petroleum hydrocarbons and a maximum of 20% was produced from metabolism of modern carbon sources. In contrast, in a nearby uncontaminated control soil, the microbial community maintained a nearly modern 14C signature, suggesting preferential degradation of more labile, recent carbon. Mass balance using δ13C and Δ14C of soil CO2 demonstrated that mineralization of petroleum carbon contributed 60-65% of soil CO2 at the contaminated site. The remainder was derived from atmospheric (27-30%) and decomposition of non- petroleum natural organic carbon (5-10%). The clean control exhibited substantially lower CO2 concentrations that were derived from atmospheric (55%) and natural organic carbon (45%) sources. This study highlights the value of using multiple carbon isotopes to identify degradation pathways in petroleum- contaminated soils undergoing phytoremediation and the power of natural abundance 14C to detect petroleum metabolism in natural microbial communities.

  5. Study of the bacterial diversity of foods: PCR-DGGE versus LH-PCR.

    Science.gov (United States)

    Garofalo, Cristiana; Bancalari, Elena; Milanović, Vesna; Cardinali, Federica; Osimani, Andrea; Sardaro, Maria Luisa Savo; Bottari, Benedetta; Bernini, Valentina; Aquilanti, Lucia; Clementi, Francesca; Neviani, Erasmo; Gatti, Monica

    2017-02-02

    The present study compared two culture-independent methods, polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and length-heterogeneity polymerase chain reaction (LH-PCR), for their ability to reveal food bacterial microbiota. Total microbial DNA and RNA were extracted directly from fourteen fermented and unfermented foods, and domain A of the variable regions V1 and V2 of the 16S rRNA gene was analyzed through LH-PCR and PCR-DGGE. Finally, the outline of these analyses was compared with bacterial viable counts obtained after bacterial growth on suitable selective media. For the majority of the samples, RNA-based PCR-DGGE revealed species that the DNA-based PCR-DGGE was not able to highlight. When analyzing either DNA or RNA, LH-PCR identified several lactic acid bacteria (LAB) and coagulase negative cocci (CCN) species that were not identified by PCR-DGGE. This phenomenon was particularly evident in food samples with viable loadsPCR was able to detect a higher number of peaks in the analyzed food matrices relative to species identified by PCR-DGGE. In light of these findings, it may be suggested that LH-PCR shows greater sensitivity than PCR-DGGE. However, PCR-DGGE detected some other species (LAB included) that were not detected by LH-PCR. Therefore, certain LH-PCR peaks not attributed to known species within the LH-PCR database could be solved by comparing them with species identified by PCR-DGGE. Overall, this study also showed that LH-PCR is a promising method for use in the food microbiology field, indicating the necessity to expand the LH-PCR database, which is based, up to now, mainly on LAB isolates from dairy products. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Changes in soil microbial community structure associated with two types of genetically engineered plants analyzing by PLFA

    Institute of Scientific and Technical Information of China (English)

    XUE Kai; LUO Hai-feng; QI Hong-yan; ZHANG Hong-xun

    2005-01-01

    With the rapid expansion of GEPs(genetically engineered plants), people are more and more concerned about the ecological risks brought by their release. Assessing the effect of GEPs on soil microbial ecology is indispensable to study their ecological risks. In our study, the phospholipids fatty acid(PLFA) method was used to analyze the microbial community of soil samples collected from fields with two types of GEPs-Bt transgenic corn and PVY(potato virus Y) cell protein gene transgenic potato. The principal components analysis(PCA) showed all controls were on the right of related GEPs samples along the PC1 (the first principal component) axis, which means a decrease of fungi in soils with genetically engineered crop since most of PLFAs that are strongly positively correlated with PC1 represent fungi. For samples collected from Bt transgenic cornfield, the ratios of gram-positive to gram-negative bacteria were less than those of controls. For samples of transgenic potato field, these ratios were lower than those of controls when soils were collected from deep layer(20-40 cm), but were higher when soils collected from surface layer(0-20 cm). For soils collected from 0-20 cm, the ratios of fungi to bacteria for all GEPs samples were at the same level. So were such rations for all controls. Changes of soil microbial community in two types of GEPs fields were detected in our study, but the causes and more information still needs further study.

  7. Using DGGE and 16S rRNA gene sequence analysis to evaluate changes in oral bacterial composition.

    Science.gov (United States)

    Chen, Zhou; Trivedi, Harsh M; Chhun, Nok; Barnes, Virginia M; Saxena, Deepak; Xu, Tao; Li, Yihong

    2011-01-01

    To investigate whether a standard dental prophylaxis followed by tooth brushing with an antibacterial dentifrice will affect the oral bacterial community, as determined by denaturing gradient gel electrophoresis (DGGE) combined with 16S rRNA gene sequence analysis. Twenty-four healthy adults were instructed to brush their teeth using commercial dentifrice for 1 week during a washout period. An initial set of pooled supragingival plaque samples was collected from each participant at baseline (0 h) before prophylaxis treatment. The subjects were given a clinical examination and dental prophylaxis and asked to brush for 1 min with a dentifrice containing 0.3% triclosan, 2.0% PVM/MA copolymer and 0.243% sodium fluoride (Colgate Total). On the following day, a second set of pooled supragingival plaque samples (24 h) was collected. Total bacterial genomic DNA was isolated from the samples. Differences in the microbial composition before and after the prophylactic procedure and tooth brushing were assessed by comparing the DGGE profiles and 16S rRNA gene segments sequence analysis. Two distinct clusters of DGGE profiles were found, suggesting that a shift in the microbial composition had occurred 24 h after the prophylaxis and brushing. A detailed sequencing analysis of 16S rRNA gene segments further identified 6 phyla and 29 genera, including known and unknown bacterial species. Importantly, an increase in bacterial diversity was observed after 24 h, including members of the Streptococcaceae family, Prevotella, Corynebacterium, TM7 and other commensal bacteria. The results suggest that the use of a standard prophylaxis followed by the use of the dentifrice containing 0.3% triclosan, 2.0% PVM/MA copolymer and 0.243% sodium fluoride may promote a healthier composition within the oral bacterial community.

  8. Dynamic changes of microbial community diversity in a photohydrogen producing reactor monitored by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    YING Yanling; LV Zhenmei; MIN Hang; CHENG Jun

    2008-01-01

    A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which corresponded to different running periods of the reactor. The optimal hydrogen producing community formed on day 10. Using DGGE analysis with the pufM gene fragments was superior to V3-16S rDNA region genes for detecting the dynamic variations of the photosynthetic bacteria population during hydrogen production. The comparative sequence analysis of excised DGGE bands showed the relationship between specific population structures and system performance. Rhodopseudomonas palustris was presumed as one of the dominant community members for hydrogen production in the reactor. The PCR-DGGE protocol was proven to be a good tool for monitoring the photohydrogen production in real time and offered the available information to improve the photohydrogen producing system.

  9. Approach to determine the diversity of Legionella species by nested PCR-DGGE in aquatic environments

    Science.gov (United States)

    Huang, Wen-Chien; Tsai, Hsin-Chi; Tao, Chi-Wei; Chen, Jung-Sheng; Shih, Yi-Jia; Kao, Po-Min; Huang, Tung-Yi; Hsu, Bing-Mu

    2017-01-01

    In this study, we describe a nested PCR-DGGE strategy to detect Legionella communities from river water samples. The nearly full-length 16S rRNA gene was amplified using bacterial primer in the first step. After, the amplicons were employed as DNA templates in the second PCR using Legionella specific primer. The third round of gene amplification was conducted to gain PCR fragments apposite for DGGE analysis. Then the total numbers of amplified genes were observed in DGGE bands of products gained with primers specific for the diversity of Legionella species. The DGGE patterns are thus potential for a high-throughput preliminary determination of aquatic environmental Legionella species before sequencing. Comparative DNA sequence analysis of excised DGGE unique band patterns showed the identity of the Legionella community members, including a reference profile with two pathogenic species of Legionella strains. In addition, only members of Legionella pneumophila and uncultured Legionella sp. were detected. Development of three step nested PCR-DGGE tactic is seen as a useful method for studying the diversity of Legionella community. The method is rapid and provided sequence information for phylogenetic analysis. PMID:28166249

  10. DGGE Analysis of Bacterial Community Structures of Salted Raphanus sativus L.%盐渍萝卜的细菌菌群结构 DGGE 分析

    Institute of Scientific and Technical Information of China (English)

    尹礼国; 高煜然; 李华兰; 马双艳; 魏劲松; 张其圣; 陈功; 吴正云; 张文学

    2015-01-01

    Salting is an effective technology for improving the development of Raphanus sativus L. industry chain.The bacterial community structures of salted Raphanus sativus L.and its salted water pickled for 178 days and 539 days are analyzed by denatured gradient gel electrophoresis (DGGE). The bacterial community structures are similar with each other.The dominant bacteria groups are all Lactobacillus in salted Raphanus sativus L.and salted water,the gene levels are various.The operation of DGGE is easy,the result could reveal the bacterial community structure,and the advantage of DGGE is unique in the study of bacterial community structure of salted Raphanus sativus L.%萝卜盐渍是一种有效的萝卜加工技术,对萝卜产业化发展具有十分重要的意义。采用变性梯度凝胶电泳技术(denatured gradient gel electrophoresis,DGGE)对腌渍178天与539天的盐渍萝卜及其盐渍水的细菌菌群结构分析表明,两种腌渍时间的盐渍萝卜的细菌菌群结构相似,优势菌群均为乳杆菌,基因水平上呈多样性。DGGE 操作简便,能够较好地反映盐渍萝卜的细菌菌群变化,在盐渍萝卜的细菌菌群结构分析中具有独特的优势。

  11. A methodology for a quantitative interpretation of DGGE with the help of mathematical modelling: application in biohydrogen production.

    Science.gov (United States)

    Tapia, Estela; Donoso-Bravo, Andres; Cabrol, Léa; Alves, Madalena; Pereira, Alcina; Rapaport, Alain; Ruiz-Filippi, Gonzalo

    2014-01-01

    Molecular biology techniques provide valuable insights in the investigation of microbial dynamics and evolution. Denaturing gradient gel electrophoresis (DGGE) analysis is one of the most popular methods which have been used in bioprocess assessment. Most of the anaerobic digestion models consider several microbial populations as state variables. However, the difficulty of measuring individual species concentrations may cause inaccurate model predictions. The integration of microbial data and ecosystem modelling is currently a challenging issue for improved system control. A novel procedure that combines common experimental measurements, DGGE, and image analysis is presented in this study in order to provide a preliminary estimation of the actual concentration of the dominant bacterial ribotypes in a bioreactor, for further use as a variable in mathematical modelling of the bioprocess. This approach was applied during the start-up of a continuous anaerobic bioreactor for hydrogen production. The experimental concentration data were used for determining the kinetic parameters of each species, by using a multi-species chemostat-model. The model was able to reproduce the global trend of substrate and biomass concentrations during the reactor start-up, and predicted in an acceptable way the evolution of each ribotype concentration, depicting properly specific ribotype selection and extinction.

  12. Application of PCR-DGGE in Research of Bacterial Diversity in Drinking Water

    Institute of Scientific and Technical Information of China (English)

    QING WU; XIN-HUA ZHAO; SHENG-YUE ZHAO

    2006-01-01

    Objective To analyze the structure of bacteria in drinking water by molecular biological techniques. Methods DNA of bacteria in drinking water was directly extracted without culture. 16S ribosomal DNA fragments, including V-6, -7, and -8regions, were amplified with universal primers (EUBf933GC and EUBr1387) and analyzed by DGGE. Results DGGE indicated that amplification products could be separated. The results showed that DGGE could be used in the separation of different microbial 16SrRNA genes extracted from drinking water. Though there were special bacteria in different water samples, the predominant bacteria were essentially the same. Three sequences of the reclaimed specific bands were obtained, and phylogenetic tree of these bands was made. Conclusion Bacterial diversity in drinking water is identified by molecular biological techniques.

  13. Community analysis of ammonia oxidizer in the oxygen-limited nitritation stage of OLAND system by DGGE of PCR amplified 16S rDNA Fragments and FISH

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dan; ZHANG De-min; LIU Yao-ping; CAO Wen-wei; CHEN Guan-xiong

    2004-01-01

    OLAND(oxygen limited autotrophic nitrification and denitrification) nitrogen removal system was constructed by coupling with oxygen limited nitritation stage and anaerobic ammonium oxidation stage. Ammonia oxidizer, as a kind of key bacteria in N cycle, plays an important role at the oxygen limited nitritation stage of OLAND nitrogen removal system. In this study, specific amplification of 16S rDNA fragment of ammonia oxidizer by nested PCR, separation of mixed PCR samples by denaturing gradient gel electrophoresis(DGGE), and the quantification of ammonia oxidizer by Fluorescence in situ hybridization(FISH) were combined to investigate the shifts of community composition and quantity of ammonia oxidizer of the oxygen limited nitritation stage in OLAND system. It showed that the community composition of ammonia oxidizer changed drastically when dissolved oxygen was decreased gradually, and the dominant ammonia oxidizer of the steady nitrite accumulation stage were completely different from that of the early stage of oxygen limited nitritation identified by DGGE . It was concluded that the Nitrosomonas may be the dominant genus of ammonia oxidizer at the oxygen limited nitritation stage of OLAND system characterized by nested PCR-DGGE and FISH, and the percentage of Nitrosomonas was 72.5% ( 0.8% of ammonia oxidizer at the steady nitrite accumulation stage detected by FISH.

  14. Spatial heterogeneity in a deep artificial lake plankton community revealed by PCR-DGGE fingerprinting

    Science.gov (United States)

    Li, Qiang; Zhao, Yue; Zhang, Xu; Wei, Yuquan; Qiu, Linlin; Wei, Zimin; Li, Fuheng

    2015-05-01

    To explore the spatial heterogeneity of plankton communities in a deep artificial lake (Songhua Lake, China), samples were collected at seven sites. Samples were investigated by denaturing gradient gel electrophoresis (DGGE) analysis of the PCR-amplified 16S and 18S rRNA genes and specific bands were sequenced. Cluster analysis of the DGGE profiles revealed that all of the samples grouped into two distinct clusters, in accordance with sampling site; while in each cluster, the divergence of sub-clusters correlated with sampling depth. Sequence analysis of selected dominant DGGE bands revealed that most sequenced phylotypes (84%) exhibited ≥97% similarity to the closest sequences in GenBank, and were affiliated with ten common freshwater plankton phyla ( Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Bacillariophyta, Pyrrophyta, Cryptophyta, Ciliophora, Stramenopiles, and Rotifera). Several of these groups are also found worldwide, indicating the cosmopolitan distribution of the phylotypes. The relationships between DGGE patterns and environmental factors were analyzed by redundancy analysis (RDA). The results suggested that, total nitrogen, nitrate, nitrite, ammonia, and CODMn concentrations, and water temperature were strongly correlated with the variation in plankton composition.

  15. Relating MEC population dynamics to anode performance from DGGE and electrical data

    NARCIS (Netherlands)

    Croese, Elsemiek; Keesman, Karel J.; Widjaja-Greefkes, (Aura) H. C. A.; Geelhoed, Jeanine S.; Plugge, Caroline M.; Sleutels, Tom H. J. A.; Stams, A; Euverink, Gert-Jan W.

    The microbial electrolysis cell (MEC) is a promising system for H-2 production, but little is known about the active microbial population in MEC systems. Therefore, the microbial community of five different MEC graphite felt anodes was analyzed using denaturing gradient gel electrophoresis (DGGE)

  16. PCR-DGGE analysis of nematode diversity in Cu-contaminated soil

    Institute of Scientific and Technical Information of China (English)

    WANG Shi-Bin; LI Qi; LIANG Wen-Ju; JIANG Yong; JIANG Si-Wei

    2008-01-01

    A wheat pot experiment was conducted under greenhouse conditions to assess the effect of copper contamination on soil nematode diversity by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method and morphological analysis.The soil was treated with CuSO4.5H2O at the following concentrations:0,50,100,200,400,and 800 mg kg-1 dry soil,and the soil samples were collected at wheat jointing and ripening stages.Nematode diversity index (H') from morphological analysis showed no difference between the control and the treated samples in either of the sampling dates.At the wheat ripening stage,nematode diversity obtained by the PCR-DGGE method decreased noticeably in the Cu800 treatment in comparison with the control.With optimization of the method of nematode DNA extraction,PCR-DGGE could give more information on nematode genera,and the intensity of the bands could reflect the abundance of nematode genera in the assemblage.The PCR-DGGE method proved promising in distinguishing nematode diversity in heavy metal contaminated soil.

  17. Relating MEC population dynamics to anode performance from DGGE and electrical data

    NARCIS (Netherlands)

    Croese, Elsemiek; Keesman, Karel J.; Widjaja-Greefkes, (Aura) H. C. A.; Geelhoed, Jeanine S.; Plugge, Caroline M.; Sleutels, Tom H. J. A.; Stams, A; Euverink, Gert-Jan W.

    2013-01-01

    The microbial electrolysis cell (MEC) is a promising system for H-2 production, but little is known about the active microbial population in MEC systems. Therefore, the microbial community of five different MEC graphite felt anodes was analyzed using denaturing gradient gel electrophoresis (DGGE) pr

  18. Microbial community analysis of shallow subsurface samples with PCR-DGGE

    Energy Technology Data Exchange (ETDEWEB)

    Itaevaara, M.; Suihko, M.-L.; Kapanen, A.; Piskonen, R.; Juvonen, R. [VTT Biotechnology, Espoo (Finland)

    2005-11-15

    This work is part of the site investigations for the disposal of spent nuclear fuel in Olkiluoto bedrock. The purpose of the research was to study the suitability of PCR-DGGE (polymerase chain reaction - denaturing gradient gel electrophoresis) method for monitoring of hydrogeomicrobiology of Olkiluoto repository site. PCR-DGGE method has been applied for monitoring microbial processes in several applications. The benefit of the method is that microorganisms are not cultivated but the presence of microbial communities can be monitored by direct DNA extractions from the environmental samples. Partial 16SrDNA gene sequence is specifically amplified by PCR (polymerase chain reaction) which detect bacteria as a group. The gene sequences are separated in DGGE, and the nucleotide bands are then cut out, extracted, sequenced and identified by the genelibraries by e.g. Blast program. PCR-DGGE method can be used to detect microorganisms which are present abundantly in the microbial communities because small quantities of genes cannot be separated reliably. However, generally the microorganisms involved in several environmental processes are naturally enriched and present as major population. This makes it possible to utilize PCRDGGE as a monitoring method. In this study, we studied the structure of microbial communities in ten ground water samples originating from Olkiluoto. Two universal bacterial primer sets were compared which amplified two different regions of the 16SrDNA gene. The longer sequence amplified resulted in fewer bands in DGGE, in addition there were problems with purification of the sequences after DGGE. The shorter sequence gave more bands in DGGE and more clear results without any amplification problems. Comparison of the sequences from the gene-libraries resulted in the detection of the same species by both primer sets, in addition some different species were detected. Several species were anaerobic bacteria, such as acetogenic and sulphate reducing

  19. Application of denaturing gradient gel electrophoresis (DGGE) to the analysis of endodontic infections.

    Science.gov (United States)

    Siqueira, José F; Rôças, Isabela N; Rosado, Alexandre S

    2005-11-01

    The recent expanding use of cultivation-independent techniques for bacterial identification is reliant on the lack of knowledge of the conditions under which most bacteria are growing in their natural habitat and the difficulty to develop culture media that accurately reproduce these conditions. A molecular method that has been recently used in several areas to examine the bacterial diversity living in diverse environments is the denaturing gradient gel electrophoresis (DGGE). In DGGE, polymerase chain reaction (PCR)-generated DNA fragments of the same length but with different base-pair sequences can be separated. Separation is based on electrophorectic mobility of a partially melted double-strand DNA molecule in polyacrylamide gels, which is decreased when compared with that of the completely helical form of the molecule. Molecules with different sequences may have a different melting behavior and will therefore stop migrating at different positions in the gel. Application of the PCR-DGGE method in endodontic research has revealed that there are significant differences in the predominant bacterial composition between asymptomatic and symptomatic cases. This suggests that the structure of the bacterial community can play a role in the development of symptoms. In addition, new bacterial phylotypes have been disclosed in primary endodontic infections. PCR-DGGE has also confirmed that intra-radicular infections are a common finding in root-filled teeth associated with persistent periradicular lesions. The microbiota in failed cases significantly vary from teeth to teeth, with a mean number of species far higher than previously shown by culturing approaches. Application of the PCR-DGGE technique in endodontic microbiology research has the potential to shed light on several aspects of the different types of endodontic infection as well as on the effects of treatment procedures with regard to infection control.

  20. An rpoB gene-based PCR-DGGE method for simultaneous detection of multiple Vibrio species

    Institute of Scientific and Technical Information of China (English)

    Luo Peng; Hu Chaoqun; Ren Chunhua; Zhang Lvping

    2008-01-01

    Using PCR-denaturing gradient gel electrophoresis (DGGE) targeting the RNA polymerase beta subunit (rpoB) gene, a simultaneous detection method for Vibrio species was established. rpoB gene-based PCR-DGGE was carried out with eight Vibrio Reference strains (each from different species), mixed sample (including these Vibrio Reference strains),two non Vibrio strains, four environmental Vibrio strains, and three unidentified environmental strains. For comparison, 16S rRNA gene-based PCR-DGGE of the eight Vibrio Reference strains was performed with universal primers. In addition, three unidentified strains were identified by 16S rRNA and gyrB gene sequencing and API20E system in order to confirm the accuracy of rpoB gene-based PCR-DGGE detection. Results revealed that rpoB-based PCR-DGGE could well discriminate eight Vibrio Reference strains and could not discriminate different strains within the same species. The bands derived from two non Vibrio strains could not match with any bands in Reference marker. Meanwhile, 16S rRNA gene-based DGGE failed to distinguish these Reference strains. Furthermore, four out of eight Vibrio species exhibited heterogenous bands in 16S rRNA gene-based DGGE. Sequencing and API 20E identification of unidentified strains coincided with the detection by rpoB gene-based PCR-DGGE. The results demonstrated that rpoB-based PCR-DGGE provided a rapid and efficient method for simultaneous detection of multiple Vibrio species, which can avoid the limitations inherent in 16S rRNA gene-based PCR-DGGE.

  1. Limited resolution of 16S rDNA DGGE caused by melting properties and closely related DNA sequences.

    Science.gov (United States)

    Kisand, Veljo; Wikner, Johan

    2003-08-01

    The phylogenetic affiliation of 91 operational taxonomic units, randomly sampled from three aquatic microcosm experiments, was investigated by two PCR based and one culture dependent method. The occurrence of multiple melting domains and poor coupling between Tm and DGGE retardation was demonstrated to cause poor resolution at the species level in PCR-DGGE analysis of microbial communities. We also showed that the problem of multiple melting domains was particularly prone for brackish water bacterioplankton in the Flavobacterium genus, providing characteristic band morphology for this genus. Banding patterns from DGGE analysis may therefore be misinterpreted in terms of the species richness in natural bacterial communities, when using commonly applied universal primers.

  2. Detection,isolation,and identification of cadmium-resistant bacteria based on PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study focused on the screening of cadmium-resistant bacterial strains from Pb-Zn tailing.We investigated the diversity of microbial community inhabiting Dong-san-cha Pb-Zn tailing in Beijing,China,by polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene of bacterial strain,and found two dominant strains in the DGGE profile.Using special culture media,We isolated two strong cadmium-resistant bacterial strains.On the basis of morphological,physiological,and biochemical characteristics,BIOLOG,and 16S rDNA sequencing,the two strains were identified as Bacillus cereus and Enterobaeter cloacae.Minimal inhibitory concentrations (MICs) of heavy metals for the bacteria were determined.E.cloacae showed higher MIC values for heavy metals and a larger range of antibiotic resistance than B.cereus.

  3. Characterization of spoilage bacteria in pork sausage by PCR-DGGE analysis

    Directory of Open Access Journals (Sweden)

    Francesca Silva Dias

    2013-09-01

    Full Text Available To investigate microbial diversity and identify spoilage bacteria in fresh pork sausages during storage, twelve industrial pork sausages of different trademarks were stored at 4 ºC for 0, 14, 28 and 42 days, 80% relative humidity and packaged in sterile plastic bags. Microbiological analysis was performed. The pH and water activity (a w were measured. The culture-independent method performed was the Polymerase Chain Reaction - Denaturing Gradient Gel Electrophoresis (PCR-DGGE. The culture-dependent method showed that the populations of mesophilic bacteria and Lactic Acid Bacteria (LAB increased linearly over storage time. At the end of the storage time, the average population of microorganisms was detected, in general, at the level of 5 log cfu g-1. A significant (P < 0.005 increase was observed in pH and a w values at the end of the storage time. The PCR-DGGE allowed a rapid identification of dominant communities present in sausages. PCR-DGGE discriminated 15 species and seven genera of bacteria that frequently constitute the microbiota in sausage products. The most frequent spoilage bacteria identified in the sausages were Lactobacillus sakei and Brochothrix thermosphacta. The identification of dominant communities present in fresh pork sausages can help in the choice of the most effective preservation method for extending the product shelf-life.

  4. Identification of msp1 Gene Variants in Populations of Meloidogyne incognita Using PCR-DGGE

    Science.gov (United States)

    Adam, Mohamed; Hallmann, Johannes; Heuer, Holger

    2014-01-01

    Effectors of root-knot nematodes are essential for parasitism and prone to recognition by adapted variants of the host plants. This selective pressure initiates hypervariability of effector genes. Diversity of the gene variants within nematode populations might correlate with host preferences. In this study we developed a method to compare the distribution of variants of the effector gene msp1 among populations of Meloidogyne incognita. Primers were designed to amplify a 234-bp fragment of msp1. Sequencing of cloned PCR products revealed five msp1 variants from seven populations that were distinguishable in their reproduction on five host plants. A protocol for denaturing gradient gel electrophoresis (DGGE) was developed to separate these msp1 variants. DGGE for replicated pools of juveniles from the seven populations revealed ten variants of msp1. A correlation between the presence of a particular gene variant and the reproductive potential on particular hosts was not evident. Especially race 3 showed substantial variation within the population. DGGE fingerprints of msp1 tended to cluster the populations according to their reproduction rate on pepper. The developed method could be useful for analyzing population heterogeneity and epidemiology of M. incognita. PMID:25276001

  5. Design and in vitro evaluation of new rpoB-DGGE primers for ruminants.

    Science.gov (United States)

    Perumbakkam, Sudeep; Craig, A Morrie

    2011-04-01

    Two new primer sets based on the rpoB gene were designed and evaluated with bovine and ovine rumen samples. The newly developed rpoB-DGGE primer set was used along with the 16S rRNA gene-V3, and another (old) rpoB-DGGE-based primer set from a previous study to in vitro compare the bovine and ovine rumen ecosystems. The results indicate a significant (Pprimers used in the analysis. Qualitative comparison of the data provides evidence for the presence of similar phyla profiles between the 16S rRNA gene and the newly developed rpoB primers. A comparison between the two rpoB-based primer sets (old and new) showed that the old rpoB-based primers failed to amplify phylum Bacteroidetes (a common phylum in the rumen) in both bovine and ovine rumen samples. The old and new rpoB-DGGE-based primers amplified a large number of clones belonging to phylum Proteobacteria, providing a useful insight into the microbial structure of the rumen. ChaoI, ACE, Simpson, and Shannon-Weaver index analysis estimated the bovine rumen to be more diverse than the ovine rumen for all three primer sets. These results provide a new insight into the community structure among ruminants using the newly developed primers in this study. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  6. Safety evaluation and bacterial community of kung-som using PCR-DGGE technique

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    Sutanate Saelao

    2016-08-01

    Full Text Available This study evaluates the safety of kung-som which was distributed in local markets and using PCR-DGGE technique to identify microflora in kung-som. Lactic acid bacteria (LAB were found at counts of more than 7 log CFU g-1 in all samples and the total viable counts were about 5-8 log CFU g-1 . Bacillus cereus and yeasts were detected at around 2 log CFU g-1 and 5-6log CFU g-1, respectively. For DGGE analysis, LAB and coagulase negative staphylococci (CNS bacteria dominated over other microorganisms. The sequencing of the DNA bands from DGGE gels corresponding to kung-som samples showed the presence of LAB as the major microflora in the products, namely: Lactobacillus farciminis, Lactobacillus plantarum, Lactococcus garvieae, Tetragenococcus halophilus and Weissella thailandensis. In addition, Staphylococcus carnosus was detected in kung-som as minor microflora. These dominant strains would allow the development of defined starter cultures for improving the quality of kung-som.

  7. Rhizosphere bacterial communities of potato cultivars evaluated through PCR-DGGE profiles Comunidades bacterianas associadas à rizosfera de cultivares de batata avaliadas por perfis de PCR-DGGE

    Directory of Open Access Journals (Sweden)

    Enderson Petrônio de Brito Ferreira

    2008-05-01

    Full Text Available The objective of this work was to determine the shifts on the PCR-DGGE profiles of bacterial communities associated to the rhizosphere of potato cultivars, in order to generate baseline information for further studies of environmental risk assessment of genetically modified potato plants. A greenhouse experiment was carried out with five potato cultivars (Achat, Bintje, Agata, Monalisa and Asterix, cultivated in pots containing soil from an integrated system for agroecological production. The experiment was conducted in a split plot randomized block design with five cultivars, three sampling periods and five replicates. Rhizosphere samples were collected in three sampling dates during plant development. DNA of rhizosphere microorganisms was extracted, amplified by PCR using bacterial universal primers, and analyzed through DGGE. Shifts on the rhizosphere bacterial communities associated to rhizosphere of different cultivars were related to both cultivar and plant age. Differences among rhizosphere bacterial communities were clearest at the earliest plant age, tending to decrease in later stages. This variation was detected among bacterial communities of the five tested cultivars. The characterization of soil microbial communities can be part of plant breeding programs to be used on studies of environmental risk assessment of genetically modified potatoes.O objetivo deste trabalho foi determinar as alterações nos perfis de PCR-DGGE das comunidades bacterianas associadas à rizosfera de cultivares de batata, para obter informações para futuros estudos de avaliação de risco ambiental de plantas de batatas geneticamente modificadas. Foi conduzido experimento em casa de vegetação com cinco cultivares de batata (Achat, Bintje, Ágata, Monalisa e Asterix, cultivadas em vasos com solo de um sistema integrado de produção agroecológica. O delineamento experimental foi o de blocos ao acaso, em parcelas subdivididas, com cinco cultivares, tr

  8. Bacteria abundance and diversity of different life stages of Plutella xylostella (Lepidoptera: Plutellidae), revealed by bacteria culture-dependent and PCR-DGGE methods.

    Science.gov (United States)

    Lin, Xiao-Li; Pan, Qin-Jian; Tian, Hong-Gang; Douglas, Angela E; Liu, Tong-Xian

    2015-03-01

    Microbial abundance and diversity of different life stages (fourth instar larvae, pupae and adults) of the diamondback moth, Plutella xylostella L., collected from field and reared in laboratory, were investigated using bacteria culture-dependent method and PCR-DGGE analysis based on the sequence of bacteria 16S rRNA V3 region gene. A large quantity of bacteria was found in all life stages of P. xylostella. Field population had higher quantity of bacteria than laboratory population, and larval gut had higher quantity than pupae and adults. Culturable bacteria differed in different life stages of P. xylostella. Twenty-five different bacterial strains were identified in total, among them 20 strains were presented in larval gut, only 8 strains in pupae and 14 strains in adults were detected. Firmicutes bacteria, Bacillus sp., were the most dominant species in every life stage. 15 distinct bands were obtained from DGGE electrophoresis gel. The sequences blasted in GenBank database showed these bacteria belonged to six different genera. Phylogenetic analysis showed the sequences of the bacteria belonged to the Actinobacteri, Proteobacteria and Firmicutes. Serratia sp. in Proteobacteria was the most abundant species in larval gut. In pupae, unculturable bacteria were the most dominant species, and unculturable bacteria and Serratia sp. were the most dominant species in adults. Our study suggested that a combination of molecular and traditional culturing methods can be effectively used to analyze and to determine the diversity of gut microflora. These known bacteria may play important roles in development of P. xylostella.

  9. Using Position-Specific 13C and 14C Labeling and 13C-PLFA Analysis to Assess Microbial Transformations of Free Versus Sorbed Alanine

    Science.gov (United States)

    Apostel, C.; Herschbach, J.; Bore, E. K.; Kuzyakov, Y.; Dippold, M. A.

    2015-12-01

    Sorption of charged or partially charged low molecular weight organic substances (LMWOS) to soil mineral surfaces delays microbial uptake and therefore mineralization of LMWOS to CO2, as well as all other biochemical transformations. We used position-specific labeling, a tool of isotope applications novel to soil sciences, to compare the transformation mechanisms of sorbed and non-sorbed alanine in soil. Alanine as an amino acid links C- and N-cycles in soil and therefore is a model substance for the pool of LMWOS. To assess transformations of sorbed alanine, we added position-specific and uniformly 13C and 14C labeled alanine tracer to soil that had previously been sterilized by γ-radiation. The labeled soil was added to non-sterilized soil from the same site and incubated. Soil labeled with the same tracers without previous sorption was prepared and incubated as well. We captured the respired CO2 and determined its 14C-activity at increasing time intervals. The incorporation of 14C into microbial biomass was determined by chloroform fumigation extraction (CFE), and utilization of individual C positions by distinct microbial groups was evaluated by 13C-phospholipid fatty acid analysis (PLFA). A dual peak in the respired CO2 revealed two sorption mechanisms. To compare the fate of individual C atoms independent of their concentration and pool size in soil, we applied the divergence index (DI). The DI reveals the convergent or divergent behavior of C from individual molecule positions during microbial utilization. Alanine C-1 position was mainly oxidized to CO2, while its C-2 and C-3 were preferentially incorporated in microbial biomass and PLFA. This indicates that sorption by the COOH group does not protect this group from preferential oxidation. Microbial metabolism was determinative for the preferential oxidation of individual molecule positions. The use of position-specific labeling revealed mechanisms and kinetics of microbial utilization of sorbed and non

  10. Stabilization of glucose-C in microbial cell membranes (PLFA) and cell walls (amino sugars) evaluated by 13C-labelling in a field experiment

    Science.gov (United States)

    Gunina, Anna; Kuzyakov, Yakov; Glaser, Bruno

    2015-04-01

    Microorganisms control carbon (C) cycle and strongly contribute to formation of soil organic matter. Strong differences in the turnover of microbial groups and cellular compounds complicate the assessment of their contribution to microbial food webs and C sequestration in soil in situ. The uptake and incorporation of 13C labeled glucose by microbial groups were traced during 50 days after the labeling under field conditions. 13C was analysed: i) in the cytosolic pool by chloroform fumigation extraction, ii) in cell membranes by phospholipid fatty acids (PLFA), iii) in cell walls by amino sugars, and iv) remaining in bulk soil. This allowed tracing C in microbial groups as well as cellular compounds. Mean residence times (MRT) of C in PLFA and the cytosol were 47 and 150 days, respectively. Such long cytosol MRT depends on its heterogeneous composition, which includes high and low molecular weight organics. Amino sugars were mainly originated from microbial residues and thus, observation periods higher than 1 year are required for estimation of their MRT. Relative 13C incorporation (13C portion in total pool C) was the highest for PLFAs (~1.5% at day 3), whereas 13C content of the cytosol and amino sugars was one and two orders of magnitude less, respectively. Relative 13C incorporation into amino sugars of living microorganisms showed only 0.57% on day 3. Therefore, the turnover of cell membrane components is two times faster than that of cell walls, even in living microorganisms. Both PLFAs and amino sugars showed that glucose C was preferentially used by bacteria. 13C incorporation into bacterial cell walls and membranes decreased with time, but increased or remained constant for fungi, reflecting faster turnover of bacteria than fungi. Consequently, bacteria contribute more to the decomposition of low molecular weight organics, whereas fungi consume bacterial products or necromass and contribute more to long-term C stabilisation. Thus, tracing of 13C in cellular

  11. Correlating phospholipid fatty acids (PLFA) in a landfill leachate polluted aquifer with biogeochemical factors by multivariate statistical methods

    DEFF Research Database (Denmark)

    Ludvigsen, Liselotte; Albrechtsen, Hans-Jørgen; Rootzén, Helle

    1997-01-01

    Different multivariate statistical analyses were applied to phospholipid fatty acids representing the biomass composition and to different biogeochemical parameters measured in 37 samples from a landfill contaminated aquifer at Grindsted Landfill (Denmark). Principal component analysis and corres......Different multivariate statistical analyses were applied to phospholipid fatty acids representing the biomass composition and to different biogeochemical parameters measured in 37 samples from a landfill contaminated aquifer at Grindsted Landfill (Denmark). Principal component analysis....... Partial least square analysis related the phospholipid fatty acids data to the biogeochemical parameters assuming linear relationships. After selection of the optimal phospholipid fatty acid combination by genetic algorithms, good partial least squares models with low prediction errors were gained...

  12. PCR-DGGE METHOD FOR MICROFLORA ALTERATION IN SHRIMP DIGESTIVE ORGAN FOLLOWING Lactobacillus ADMINISTRATION

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    Nunak Nafiqoh

    2013-06-01

    Full Text Available Recently, bacteria as probiotic usage in aquaculture are deeply investigated. Probiotic application in aquaculture leads to alteration in bacteria community within environment and inside digestive system of the host. However, the evidence of treated bacteria presence is very limit. This study was aimed to reveal the effectiveness of PCR-DGGE method to bring some evidence of the applied probiotic existence within aquatic organism. Two species of Lactobacillus were applied in this experiment. Litopenaeus vannamei was used as host for applied bacteria, L. vannamei was reared using natural sea water in the 45 cm x 15 cm x 25 cm aerated glass tank. Twice daily of enriched Artemia were gived as nutrition during experiment. The result showed that Lactobacillus represent higher in treatment group compare with control after 20 days treatment. In the other hand there was no different of bacteria number between two treated Lactobacillus. PCR-DGGE is a rapid and reliable method for bacteria detection within aquatic organism.

  13. PCR-DGGE Analysis: Unravelling Complex Mixtures of Badnavirus Sequences Present in Yam Germplasm.

    Science.gov (United States)

    Turaki, Aliyu A; Bömer, Moritz; Silva, Gonçalo; Kumar, P Lava; Seal, Susan E

    2017-07-11

    Badnaviruses (family Caulimoviridae, genus Badnavirus) have emerged as serious pathogens especially affecting the cultivation of tropical crops. Badnavirus sequences can be integrated in host genomes, complicating the detection of episomal infections and the assessment of viral genetic diversity in samples containing a complex mixture of sequences. Yam (Dioscorea spp.) plants are hosts to a diverse range of badnavirus species, and recent findings have suggested that mixed infections occur frequently in West African yam germplasm. Historically, the determination of the diversity of badnaviruses present in yam breeding lines has been achieved by cloning and sequencing of polymerase chain reaction (PCR) products. In this study, the molecular diversity of partial reverse transcriptase (RT)-ribonuclease H (RNaseH) sequences from yam badnaviruses was analysed using PCR-dependent denaturing gradient gel electrophoresis (PCR-DGGE). This resulted in the identification of complex 'fingerprints' composed of multiple sequences of Dioscorea bacilliform viruses (DBVs). Many of these sequences show high nucleotide identities to endogenous DBV (eDBV) sequences deposited in GenBank, and fall into six monophyletic species groups. Our findings highlight PCR-DGGE as a powerful tool in badnavirus diversity studies enabling a rapid indication of sequence diversity as well as potential candidate integrated sequences revealed by their conserved nature across germplasm.

  14. Improvement of DGGE analysis by modifications of PCR protocols for analysis of microbial community members with low abundance.

    Science.gov (United States)

    Wang, Yong-Feng; Zhang, Fang-Qiu; Gu, Ji-Dong

    2014-06-01

    Denaturing gradient gel electrophoresis (DGGE) is a powerful technique to reveal the community structures and composition of microorganisms in complex natural environments and samples. However, positive and reproducible polymerase chain reaction (PCR) products, which are difficult to acquire for some specific samples due to low abundance of the target microorganisms, significantly impair the effective applications of DGGE. Thus, nested PCR is often introduced to generate positive PCR products from the complex samples, but one problem is also introduced: The total number of thermocycling in nested PCR is usually unacceptably high, which results in skewed community structures by generation of random or mismatched PCR products on the DGGE gel, and this was demonstrated in this study. Furthermore, nested PCR could not resolve the uneven representative issue with PCR products of complex samples with unequal richness of microbial population. In order to solve the two problems in nested PCR, the general protocol was modified and improved in this study. Firstly, a general PCR procedure was used to amplify the target genes with the PCR primers without any guanine cytosine (GC) clamp, and then, the resultant PCR products were purified and diluted to 0.01 μg ml(-1). Subsequently, the diluted PCR products were utilized as templates to amplify again with the same PCR primers with the GC clamp for 17 cycles, and the products were finally subjected to DGGE analysis. We demonstrated that this is a much more reliable approach to obtain a high quality DGGE profile with high reproducibility. Thus, we recommend the adoption of this improved protocol in analyzing microorganisms of low abundance in complex samples when applying the DGGE fingerprinting technique to avoid biased results.

  15. Comparison of DNA extraction kits for PCR-DGGE analysis of human intestinal microbial communities from fecal specimens

    Directory of Open Access Journals (Sweden)

    Nakatsu Cindy H

    2010-05-01

    Full Text Available Abstract Background The influence of diet on intestinal microflora has been investigated mainly using conventional microbiological approaches. Although these studies have advanced knowledge on human intestinal microflora, it is imperative that new methods are applied to facilitate scientific progress. Culture-independent molecular fingerprinting method of Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis (PCR-DGGE has been used to study microbial communities in a variety of environmental samples. However, these protocols must be optimized prior to their application in order to enhance the quality and accuracy of downstream analyses. In this study, the relative efficacy of four commercial DNA extraction kits (Mobio Ultra Clean® Fecal DNA Isolation Kit, M; QIAamp® DNA Stool Mini Kit, Q; FastDNA® SPIN Kit, FSp; FastDNA® SPIN Kit for Soil, FSo were evaluated. Further, PCR-DGGE technique was also assessed for its feasibility in detecting differences in human intestinal bacterial fingerprint profiles. Method Total DNA was extracted from varying weights of human fecal specimens using four different kits, followed by PCR amplification of bacterial 16S rRNA genes, and DGGE separation of the amplicons. Results Regardless of kit, maximum DNA yield was obtained using 10 to 50 mg (wet wt of fecal specimens and similar DGGE profiles were obtained. However, kits FSp and FSo extracted significantly larger amounts of DNA per g dry fecal specimens and produced more bands on their DGGE profiles than kits M and Q due to their use of bead-containing lysing matrix and vigorous shaking step. DGGE of 16S rRNA gene PCR products was suitable for capturing the profiles of human intestinal microbial community and enabled rapid comparative assessment of inter- and intra-subject differences. Conclusion We conclude that extraction kits that incorporated bead-containing lysing matrix and vigorous shaking produced high quality DNA from human fecal

  16. PCR-DGGE analysis of the bacterial composition of a kaolin slurry showing altered rheology.

    Science.gov (United States)

    Papp, Ildikó; Balázs, Margit; Tombácz, Etelka; Babcsán, Norbert; Kesserű, Péter; Kiss, István; Szvetnik, Attila

    2012-04-01

    Kaolin is an important industrial raw material and a basis of a range of different products. Microbial spoilage is a detrimental process observed especially in kaolin slurries, leading to low quality products and economic loss. Although the alteration of kaolin slurries in ceramic industry was observed, the process and the microbial background have not been analyzed in details. This study provides the first data using a cultivation independent molecular biological approach (PCR-DGGE) regarding the bacterial composition of an altered kaolin slurry. The results show that potential exopolymer (EPS) producer bacteria (e.g. Acinetobacter, Pseudomonas) appear in the altered kaolin slurry, which may have an important role in the modification of kaolin slurries.

  17. Assessment of the bacterial community of soils contaminated with used lubricating oil by PCR-DGGE

    Directory of Open Access Journals (Sweden)

    Naruemon Meeboon

    2016-12-01

    Full Text Available The diversity of indigenous bacteria in three soils contaminated with used lubricating oil (ULO was determined and compared using molecular analysis of bacteria cultured during the enrichment process. Sequencing analyses demonstrated that the majority of the DGGE bands in enrichment cultures were affiliated with four phyla of the domain, Bacteria: α, β, γ- Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. Soil C had a higher ULO contamination level than soil A and B, which may explain why enrichment culture C had the greatest diversity of bacteria, but further studies would be needed to determine whether ULO concentration results in higher diversity of ULO-degraders in soils. The diversity of ULO-degraders detected in these three different soils suggests that biostimulation methods for increasing the activity of indigenous microorganisms may be a viable approach to bioremediation, and that future studies to determine how to increase their activity in situ are warranted.

  18. DGGE detection and screening of lignocellulolytic bacteria from the termite gut of Coptotermes formosanus

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    Mathew, G.M.

    2011-01-01

    Full Text Available Aims: Termites thrive in terrestrial ecosystems and play an important role in the bio-recycling of lignocellulose. The objective of this study is to isolate and detect bacteria from the termite gut of Coptotermes formosanus and to screen their various enzyme activities by qualitative methods. In addition, this study was aimed to isolate lignin and furfural tolerant strains for various industrial bioprocesses.Methodology and Results: In this study, 50 worker termites of Coptotermes formosanus were collected from dead trees, from a forest in Taichung, Taiwan in June 2008 and the composition of the microbial flora from the termite guts was analyzed by DGGE analysis. The results proved that anaerobic and facultatively anaerobic bacteria consisting of Acinetobacter, Bacteroides thetaiotaomicron, Escherichia coli, and Caulobacter readily existed in the guts of termites. Although the majority of these gut symbionts have not yet been cultivated or identified, some related bacteria were isolated. Two isolates 1-8 and 2-2 of Genus Bacillus, exhibited endocellulase, protease, lipase, amylase, peroxidase and lignin peroxidase activity. Under aerobic conditions, the growth density of isolate 1-8 cultured in 1000 ppm lignin containing MSM medium was two-folds higher than cultured in MSM medium without lignin. Furthermore, the isolate 1-8 was tolerant to 20 mM furfural supplemented in the MSM medium. HPLC analysis confirmed Bacillus isolate 1-8 could degrade up to 15 mM furfural.Conclusion, significance and impact of study: Hind gut bacteria from C. formosanus were detected by culture independent DGGE method. Also, Bacillus isolates 1-8 and 2-2 obtained by culture dependent methods could withstand higher concentration of furfural and as well as lignin. These isolates may be co-cultured with ethanologenic bacteria and be used as an industrial biocatalyst for biofuel production.

  19. Association study of Demodex bacteria and facial dermatoses based on DGGE technique.

    Science.gov (United States)

    Zhao, YaE; Yang, Fan; Wang, RuiLing; Niu, DongLing; Mu, Xin; Yang, Rui; Hu, Li

    2017-03-01

    The role of bacteria is unclear in the facial skin lesions caused by Demodex. To shed some light on this issue, we conducted a case-control study comparing cases with facial dermatoses with controls with healthy skin using denaturing gradient gel electrophoresis (DGGE) technique. The bacterial diversity, composition, and principal component were analyzed for Demodex bacteria and the matched facial skin bacteria. The result of mite examination showed that all 33 cases were infected with Demodex folliculorum (D. f), whereas 16 out of the 30 controls were infected with D. f, and the remaining 14 controls were infected with Demodex brevis (D. b). The diversity analysis showed that only evenness index presented statistical difference between mite bacteria and matched skin bacteria in the cases. The composition analysis showed that the DGGE bands of cases and controls were assigned to 12 taxa of 4 phyla, including Proteobacteria (39.37-52.78%), Firmicutes (2.7-26.77%), Actinobacteria (0-5.71%), and Bacteroidetes (0-2.08%). In cases, the proportion of Staphylococcus in Firmicutes was significantly higher than that in D. f controls and D. b controls, while the proportion of Sphingomonas in Proteobacteria was significantly lower than that in D. f controls. The between-group analysis (BGA) showed that all the banding patterns clustered into three groups, namely, D. f cases, D. f controls, and D. b controls. Our study suggests that the bacteria in Demodex should come from the matched facial skin bacteria. Proteobacteria and Firmicutes are the two main taxa. The increase of Staphylococcus and decrease of Sphingomonas might be associated with the development of facial dermatoses.

  20. Monitoring exogenous and indigenous bacteria by PCR-DGGE technology during the process of microbial enhanced oil recovery.

    Science.gov (United States)

    Wang, Jun; Ma, Ting; Zhao, Lingxia; Lv, Jinghua; Li, Guoqiang; Zhang, Hao; Zhao, Ben; Liang, Fenglai; Liu, Rulin

    2008-06-01

    A field experiment was performed to monitor changes in exogenous bacteria and to investigate the diversity of indigenous bacteria during a field trial of microbial enhanced oil recovery (MEOR). Two wells (26-195 and 27-221) were injected with three exogenous strains and then closed to allow for microbial growth and metabolism. After a waiting period, the pumps were restarted and the samples were collected. The bacterial populations of these samples were analyzed by denaturing gradient gel electrophoresis (DGGE) with PCR-amplified 16S rRNA fragments. DGGE profiles indicated that the exogenous strains were retrieved in the production water samples and indigenous strains could also be detected. After the pumps were restarted, average oil yield increased to 1.58 and 4.52 tons per day in wells 26-195 and 27-221, respectively, compared with almost no oil output before the injection of exogenous bacteria. Exogenous bacteria and indigenous bacteria contributed together to the increased oil output. Sequence analysis of the DGGE bands revealed that Proteobacteria were a major component of the predominant bacteria in both wells. Changes in the bacteria population in the reservoirs during MEOR process were monitored by molecular analysis of the 16S rRNA gene sequence. DGGE analysis was a successful approach to investigate the changes in microorganisms used for enhancing oil recovery. The feasibility of MEOR technology in the petroleum industry was also demonstrated.

  1. Transfer of bacteria between stainless steel and chicken meat: A CLSM and DGGE study of biofilms

    Directory of Open Access Journals (Sweden)

    Christine C. Gaylarde

    2016-08-01

    Full Text Available This study aimed to assess the interaction between bacteria and food processing surfaces using novel methods. Microbial cross contamination between stainless steel, a common food processing material, and raw chicken was studied using microbiological culture, specialized microscope and molecular techniques. Confocal laser scanning microscopy (CLSM allowed the visualization of biofilms containing single or dual species of Escherichia coli O157:H7, Salmonella typhimurium, Bacillus cereus, Staphylococcus aureus and Pseudomonas aeruginosa, formed after 6 days’ incubation on stainless steel or 4h on raw chicken. The results provided information on intra-biofilm location and stratification of species within dual species biofilms. Top-to-bottom Z-stack images revealed that, on both materials, S. typhimurium and E. coli attached concurrently, the former in greater numbers. E. coli and B. cereus segregated on steel, E. coli more frequent near the metal surface, B. cereus almost the only species in outer layers. Few cells of S. aureus, found at all depths, were seen in the 2.9 µm thick biofilm on steel with E. coli. Greatest attachment was shown by P. aeruginosa, followed by S. typhimurium, E. coli and finally Gram positive species. Large amounts of EPS in P. aeruginosa biofilms made visualization difficult on both materials, but especially on chicken meat, a limitation of this technique. Nevertheless, CLSM was useful for determining time sequence of adhesion and species makeup of thin biofilms. The technique showed that five min contact between bacterially-contaminated chicken and sterile steel resulted in greatest transfer of P. aeruginosa, followed by S. typhimurium. This was confirmed using DGGE. Gram positive bacteria transferred poorly. A biofilm containing 2.3 × 105  cfu·cm−2 B. cereus on steel transferred an undetectable number of cells to chicken after 5 min contact. This species was unable to form biofilm on chicken when incubated for 4 h

  2. Caracterização da comunidade bacteriana endofítica de citros por isolamento, PCR específico e DGGE Characterization of the endophytic bacterial community from citrus by isolation, specific PCR and DGGE

    Directory of Open Access Journals (Sweden)

    Paulo Teixeira Lacava

    2006-04-01

    Full Text Available O objetivo deste trabalho foi caracterizar a comunidade bacteriana endofítica de plantas assintomáticas (escapes e afetadas pela clorose variegada dos citros (CVC por meio de isolamento em meio de cultura, técnica de gradiente desnaturante em gel de eletroforese (DGGE e detecção de Methylobacterium mesophilicum e Xyllela fastidiosa por meio de PCR específico, para estudar esta comunidade e sua relação com a ocorrência da CVC. A análise da comunidade bacteriana via DGGE permitiu a detecção de X. fastidiosa, bem como Klebsiella sp. e Acinetobacter sp. como endófitos de citros. Foram observados também Curtobacterium sp., Pseudomonas sp., Enterobacter sp. e Bacillus spp. Utilizando primers específicos, Methylobacterium mesophilicum e X. fastidiosa também foram observadas, reforçando hipóteses de que estas bactérias podem estar interagindo no interior da planta hospedeira.The aim of this work was to characterize endophytic bacterial community of assintomatic (escape and Citrus Variegated Chlorosis (CVC-affected citrus plants using isolation in culture medium, denaturing gradient gel electrophoresis (DGGE technique and Methylobacterium mesophilicum as well as Xylella fastidiosa specific PCR, allowing to assess this community and its interactions with CVC. The study of bacterial community by DGGE analysis allowed the detection of X. fastidiosa, as well as Klebsiella sp. e Acinetobacter sp., which were not detected previously. Curtobacterium sp., Pseudomonas sp., Enterobacter sp. and Bacillus spp. were also observed as endophyte in citrus plants. Using specific primers Methylobacterium mesophilicum and X. fastidiosa were observed, reinforcing that these bacteria could interact inside the host plant.

  3. Identification of intestinal bacterial flora in Rhipicephalus microplus ticks by conventional methods and PCR-DGGE analysis.

    Science.gov (United States)

    Xu, Xing-Li; Cheng, Tian-Yin; Yang, Hu; Yan, Fen

    2015-06-01

    In this study, we have analyzed the intestinal microbial flora associated with Rhipicephalus microplus ticks using both culture-dependent and independent methods based on PCR and denaturing gradient gel electrophoresis (PCR-DGGE). The R. microplus ticks were collected from cattle and goats in Jiangxi, Hunan and Guizhou Provinces of China. Three distinct strains of bacteria were isolated using culture-dependent methods: Staphylococcus simulans, Bacillus subtilis and Bacillus flexus strain. Nineteen distinct DGGE bands were found using PCR-DGGE analysis, and their search for identity shows that they belonged to Rickettsiaceae, Xanthomonadaceae, Coxiella sp., Ehrlichia sp., Pseudomonas sp., Ehrlichia sp., Orphnebius sp., Rickettsia peacockii, Bacillus flexus. Rickettsia peacockii and Coxiella genus were the dominant strain of the R. microplus ticks from cattle, Pseudomonas sp. and B. flexus strain were the most common species in all tick samples from goats. Ehrlichia canis were detected only in R. microplus ticks from Yongshun area in Hunan Province. The results indicate that the intestinal microbial diversity of R. microplus ticks was influenced by tick hosts and local differences in the sampling location and these two aspects may affect transmission of pathogen to humans and animals.

  4. Fecal Microbiota in Healthy Subjects Following Omnivore, Vegetarian and Vegan Diets: Culturable Populations and rRNA DGGE Profiling.

    Directory of Open Access Journals (Sweden)

    Ilario Ferrocino

    Full Text Available In this study, the fecal microbiota of 153 healthy volunteers, recruited from four different locations in Italy, has been studied by coupling viable counts, on different microbiological media, with ribosomal RNA Denaturing Gradient Gel Electrophoresis (rRNA-DGGE. The volunteers followed three different diets, namely omnivore, ovo-lacto-vegetarian and vegan. The results obtained from culture-dependent and -independent methods have underlined a high level of similarity of the viable fecal microbiota for the three investigated diets. The rRNA DGGE profiles were very complex and comprised a total number of bands that varied from 67 to 64 for the V3 and V9 regions of the 16S rRNA gene, respectively. Only a few bands were specific in/of all three diets, and the presence of common taxa associated with the dietary habits was found. As far as the viable counts are concerned, the high similarity of the fecal microbiota was once again confirmed, with only a few of the investigated groups showing significant differences. Interestingly, the samples grouped differently, according to the recruitment site, thus highlighting a higher impact of the food consumed by the volunteers in the specific geographical locations than that of the type of diet. Lastly, it should be mentioned that the fecal microbiota DGGE profiles obtained from the DNA were clearly separated from those produced using RNA, thus underlining a difference between the total and viable populations in the fecal samples.

  5. Fecal Microbiota in Healthy Subjects Following Omnivore, Vegetarian and Vegan Diets: Culturable Populations and rRNA DGGE Profiling.

    Science.gov (United States)

    Ferrocino, Ilario; Di Cagno, Raffaella; De Angelis, Maria; Turroni, Silvia; Vannini, Lucia; Bancalari, Elena; Rantsiou, Kalliopi; Cardinali, Gianluigi; Neviani, Erasmo; Cocolin, Luca

    2015-01-01

    In this study, the fecal microbiota of 153 healthy volunteers, recruited from four different locations in Italy, has been studied by coupling viable counts, on different microbiological media, with ribosomal RNA Denaturing Gradient Gel Electrophoresis (rRNA-DGGE). The volunteers followed three different diets, namely omnivore, ovo-lacto-vegetarian and vegan. The results obtained from culture-dependent and -independent methods have underlined a high level of similarity of the viable fecal microbiota for the three investigated diets. The rRNA DGGE profiles were very complex and comprised a total number of bands that varied from 67 to 64 for the V3 and V9 regions of the 16S rRNA gene, respectively. Only a few bands were specific in/of all three diets, and the presence of common taxa associated with the dietary habits was found. As far as the viable counts are concerned, the high similarity of the fecal microbiota was once again confirmed, with only a few of the investigated groups showing significant differences. Interestingly, the samples grouped differently, according to the recruitment site, thus highlighting a higher impact of the food consumed by the volunteers in the specific geographical locations than that of the type of diet. Lastly, it should be mentioned that the fecal microbiota DGGE profiles obtained from the DNA were clearly separated from those produced using RNA, thus underlining a difference between the total and viable populations in the fecal samples.

  6. Microbial diversity of traditional Vietnamese alcohol fermentation starters (banh men) as determined by PCR-mediated DGGE.

    Science.gov (United States)

    Thanh, Vu Nguyen; Mai, Le Thuy; Tuan, Duong Anh

    2008-12-10

    The diversity of fungi and bacteria associated with traditional Vietnamese alcohol fermentation starters (banh men) was investigated by PCR-mediated DGGE. From 52 starter samples, 13 species of fungi (including yeasts) and 23 species of bacteria were identified. The fungal composition of the starters was consistent with little variation among samples. It consisted of amylase producers (Rhizopus oryzae, R. microsporus, Absidia corymbifera, Amylomyces sp., Saccharomycopsis fibuligera), ethanol producers (Saccharomyces cerevisiae, Issatchenkia sp., Pichia anomala, Candida tropicalis, P. ranongensis, Clavispora lusitaniae), and (opportunistic) contaminants (Xeromyces bisporus, Botryobasidium subcoronatum). The bacterial microflora of starters was highly variable in species composition and dominated by lactic acid bacteria (LAB). The most frequent LAB were Pediococcus pentosaceus, Lactobacillus plantarum, L. brevis, Weissella confusa, and W. paramesenteroides. Species of amylase-producing Bacillus (Bacillus subtilis, B. circulans, B. amyloliquefaciens, B. sporothermodurans), acetic acid bacteria (Acetobacter orientalis, A. pasteurianus), and plant pathogens/environment contaminants (Burkholderia ubonensis, Ralstonia solanacearum, Pelomonas puraquae) were also detected. Fungal DGGE was found to be useful for evaluating starter type and starter quality. Moreover, in view of the high biological diversity of these substrates, bacterial DGGE may be useful in determining the identity of a starter. The constant occurrence of opportunistic contaminants highlights the need for careful examination of the role of individual components in starters.

  7. Isolation of deoxynivalenol-transforming bacteria from the chicken intestines using the approach of PCR-DGGE guided microbial selection

    Directory of Open Access Journals (Sweden)

    Li Xiu-Zhen

    2010-06-01

    Full Text Available Abstract Background Contamination of grains with trichothecene mycotoxins, especially deoxynivalenol (DON, has been an ongoing problem for Canada and many other countries. Mycotoxin contamination creates food safety risks, reduces grain market values, threatens livestock industries, and limits agricultural produce exports. DON is a secondary metabolite produced by some Fusarium species of fungi. To date, there is a lack of effective and economical methods to significantly reduce the levels of trichothecene mycotoxins in food and feed, including the efforts to breed Fusarium pathogen-resistant crops and chemical/physical treatments to remove the mycotoxins. Biological approaches, such as the use of microorganisms to convert the toxins to non- or less toxic compounds, have become a preferred choice recently due to their high specificity, efficacy, and environmental soundness. However, such approaches are often limited by the availability of microbial agents with the ability to detoxify the mycotoxins. In the present study, an approach with PCR-DGGE guided microbial selection was developed and used to isolate DON -transforming bacteria from chicken intestines, which resulted in the successful isolation of several bacterial isolates that demonstrated the function to transform DON to its de-epoxy form, deepoxy-4-deoxynivalenol (DOM-1, a product much less toxic than DON. Results The use of conventional microbiological selection strategies guided by PCR-DGGE (denaturing gradient gel electrophoresis bacterial profiles for isolating DON-transforming bacteria has significantly increased the efficiency of the bacterial selection. Ten isolates were identified and isolated from chicken intestines. They were all able to transform DON to DOM-1. Most isolates were potent in transforming DON and the activity was stable during subculturing. Sequence data of partial 16S rRNA genes indicate that the ten isolates belong to four different bacterial groups

  8. Monitoring of changes in lactic acid bacteria during production of Thai traditional fermented shrimp (Kung-Som by culturing method and PCR-DGGE technique

    Directory of Open Access Journals (Sweden)

    Kanokwan Thongruck

    2017-02-01

    Full Text Available The lactic acid bacteria (LAB ecology of Kung-Som, a traditional Thai fermented shrimp, was investigated using culture-dependent and culture-independent methods. Kung-Som was fermented at room temperature under anaerobic condition for 7 days using autochthonous fermentation. The viable counts revealed a dominance of LAB, from the 16S rRNA gene V6-V8 sequence analysis of the isolates, Enterococcus faecalis, Enterococcus sanguinicola, Weissella cibaria, Weissella confusa, Enterococcus sp., Leuconostoc pseudomesenteroides and Lactobacillus plantarum were observed. The total microbial community was profiled without cultivation by analyzing the DNA that was directly extracted from the Kung-Som samples. The 16S rRNA gene V6-V8 regions were used as targets in the denaturing gradient gel electrophoresis (DGGE, profiling of the LAB. Pediococcus argentinicus, Lactococcus lactis subsp. lactis, Lactococcus garvieae, Lactobacillus curvatus, Lactobacillus sakei and Lact. plantarum were observed. Our results provide evidence of the necessity to combine the two methods for better description of microbial communities in Kung-Som fermentation.

  9. Effect of methamidophos on soil fungi community in microcosms by plate count, DGGE and clone library analysis

    Institute of Scientific and Technical Information of China (English)

    LI Xinyu; ZHANG Huiwen; WU Minna; ZHANG Yan; ZHANG Chenggang

    2008-01-01

    Methamidophos was widely used a pesticide in northern China. The potential influences of methamidophos on soil fungal community in black soil were assessed by plate count, 28S rDNA-PCR-DGGE, and clone library analysis. Three methamidophos levels (50, 150, and 250 mg/kg) were tested in soil microcosms. Results from plate count during a 60-d microcosm experiment showed that high concentrations of methamidophos (250 mg/kg) could significantly stimulate fungal populations. DCGE (denaturing gradient gel electrophoresis) fingerprinting patterns showed a significant difference between the responses of culturable and total fungi communities under the stress of methamidophos. Shannon diversity indices calculated from DGGE profiles indicated that culturable fungi in all microcosms with methamidophos treatment increased after 1 week of incubation. However, the diversity indices of total fungi decreased in the first week, as compared to the stimulation of culturable fungi. At the 8th week, however, all the microcosms treated by methamidophos were similar to the control microcosms in community structure as suggested by the Shannon diversity indices for both culturable and total fungi. In contrast, after 1 week the fungal structure of culturable and unculturable both were disturbed to different extent under the stresses of methamidophos by clustering analysis. Clone sequencing analysis indicated the stimulation of pathogenic and unculturable fungal populations by methamidophos treatment, suggetsing potential risks of plant disease outbreak.

  10. Comparison of ITS and 18S rDNA for estimating fungal diversity using PCR-DGGE.

    Science.gov (United States)

    Liu, Jie; Yu, Yaoyao; Cai, Zhang; Bartlam, Mark; Wang, Yingying

    2015-09-01

    Both the internal transcribed spacer (ITS) region and 18S rRNA genes are broadly applied in molecular fingerprinting studies of fungi. However, the differences in those two ribosomal RNA regions are still largely unknown. In the current study, three sets of most suitable subunit ribosomes in ITS and 18S rRNA were compared using denaturing gradient gel electrophoresis (DGGE) under the optimum experimental conditions. Ten samples from both aquatic and soil environments were tested. The results revealed that the ITS region produced range-weighted richness in the range 36-361, which was significantly higher than that produced by 18S rDNA. There was a similar tendency in terms of the Shannon-Weaver diversity index and community dynamics in both water and soil samples. Samples from water and soil were better separated using ITS than 18S rDNA in principal component analysis of DGGE bands. Our study suggests that the ITS region is more precise and has more potential than 18S rRNA genes in fungal community analysis.

  11. Monitoring impact of mefenacet treatment on soil microbial communities by PCR-DGGE fingerprinting and conventional testing procedures

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effect of acetanilide herbicide mefenacet on soil microbial communities was studied using paddy soil samples with different short-term treatments. The culturable bacteria (plate counts), dehydrogenase activity and changes in community structure(denaturing gradient gel electrophoresis (DGGE) analysis) were used for biological community assessments. Mefenacet was a significant stimulus to cultural aerobic bacteria and dehydrogenase activity while Sphingobacterium multivorum Y1, a bacterium efficiently degrading the mefenacet, only induced the increasing colony-forming unit (CFU) of bacteria but little effect on dehydrogenase activity during the whole experiment. The degree of similarity between the 16S rDNA profiles of the communities was quantified by numerically analyzing the DGGE band patterns. Similarity dendrograms showed that the microbial community structures of the mefenacet-treated and non-treated soils were not significantly different. But supplement ofS. multivorum Y1 could increase the diversity of the microbial community in the mefenacet-polluted paddy soil. This work is a new attempt to apply the S. multivorum Y1for remediation of the mefenacet-polluted environments.

  12. Approach to Analyze the Diversity of Myxobacteria in Soil by Semi-Nested PCR-Denaturing Gradient Gel Electrophoresis (DGGE) Based on Taxon-Specific Gene

    Science.gov (United States)

    Li, Baiyuan; Yao, Qing; Zhu, Honghui

    2014-01-01

    The genotypic diversity of insoluble macromolecules degraded myxobacteria, provided an opportunity to discover new bacterial resources and find new ecological functions. In this study, we developed a semi-nested-PCR-denaturing gradient gel electrophoresis (DGGE) strategy to determine the presence and genotypic diversity of myxobacteria in soil. After two rounds of PCR with myxobacteria-specific primers, an 194 bp fragment of mglA, a key gene involved in gliding motility, suitable for DGGE was obtained. A large number of bands were observed in DGGE patterns, indicating diverse myxobacteria inhabiting in soils. Furthermore, sequencing and BLAST revealed that most of the bands belonged to the myxobacteria-group, and only three of the twenty-eight bands belonged to other group, i.e., Deinococcus maricopensis. The results verified that myxobacterial strains with discrepant sequence compositions of gene mglA could be discriminated by DGGE with myxobacteria-specific primers. Collectively, the developed semi-nested-PCR-DGGE strategy is a useful tool for studying the diversity of myxobacteria. PMID:25280065

  13. PCR-DGGE analysis of intestinal bacteria and effect of Bacillus spp. on intestinal microbial diversity in kuruma shrimp ( Marsupenaeus japonicus)

    Science.gov (United States)

    Liu, Huaide; Liu, Mei; Wang, Baojie; Jiang, Keyong; Jiang, Shan); Sun, Shujuan; Wang, Lei

    2010-07-01

    In this study, the intestinal microbiota of kuruma shrimp ( Marsupenaeus japonicus) was examined by molecular analysis of the 16S rDNA to identify the dominant intestinal bacteria and to investigate the effects of Bacillus spp. on intestinal microbial diversity. Samples of the intestines of kuruma shrimp fed normal feed and Bacillus spp. amended feed. PCR and denaturing gradient gel electrophoresis (DGGE) analyses were then performed on DNA extracted directly from the guts. Population fingerprints of the predominant organisms were generated by DGGE analysis of the universal V3 16S rDNA amplicons, and distinct bands in the gels were sequenced. The results suggested that the gut of kuruma shrimp was dominated by Vibrio sp. and uncultured gamma proteobacterium. Overall, the results of this study suggest that PCR-DGGE is a possible method of studying the intestinal microbial diversity of shrimp.

  14. 饲喂蚕豆的草鱼肠道细菌群落的PCR-DGGE 分析%PCR-DGGE analysis of intestinal microecology of Ctenopharyngodon idellus fed with Vicia faba

    Institute of Scientific and Technical Information of China (English)

    吴康; 胡俊; 黄晓声; 夏虎; 陈亮; 李男; 张学振

    2014-01-01

    为探讨饲喂蚕豆( Vicia faba)对草鱼( Ctenopharyngodon idellus)肠道菌群的影响,采用PCR-DGGE技术比较了饲喂蚕豆的草鱼(脆肉鲩组)及饲喂配合饲料的草鱼(普通草鱼组)肠道微生物菌群的异同。结果显示, DGGE图谱上出现了20条明显条带,表明脆肉鲩组及普通草鱼组肠道中均存在大量细菌群落。对这20条条带测序后,获得了其中17条条带的序列,这17条条带中有9条是尚未被培养的细菌。经分析发现,这17条条带分属于变形菌门( Proteobacteria )、放线菌门( Actinobacteria )、厚壁菌门( Firmicutes )、拟杆菌门( Bacteroidetes )及未分类的细菌,其中变形菌门为两组肠道的优势菌。实验还发现,饲喂蚕豆对肠内容物菌群的影响大于对肠壁菌群的影响。结果表明,饲喂蚕豆不改变草鱼肠道菌群的种类,但对肠道菌群的相对丰度有一定影响。%To evaluate the effect of faba bean on intestinal flora , the intestinal microbiota of crisp grass carp group ( grass carp fed with faba bean ) and grass carp group ( grass carp fed with formula feed ) were investigated using 16S rDNA PCR denaturing gradient gel electrophoresis (PCR-DGGE) technology.Twenty DGGE bands appearing in DGGE fingerprint re-vealed that there were numerous intestinal microbiota in the two groups .Seventeen DGGE bands were successfully se-quenced.However, nine of these bands were classified as unculturable according to the phylogenetic analysis .The domi-nant bacteria in the fore-gut and mid-gut of the two groups all belonged to Proteobacteria , and other bacteria identified be-longed to actinobacteria, firmicutes, bacteroidetes and unclassified-bacteria.The result also showed that the influence caused by faba bean on intestinal microbiota was more remarkable in intestinal content than in intestinal wall .These results suggested that feeding faba bean did not change the microbial

  15. Dynamics of oral microbial community profiling during severe early childhood caries development monitored by PCR-DGGE.

    Science.gov (United States)

    Tao, Ye; Zhou, Yan; Ouyang, Yong; Lin, HuanCai

    2013-09-01

    To monitor the longitudinal changes in oral microbial diversity of children with severe early childhood caries (S-ECC) compared to caries free (CF) controls. Dental plaque samples of 12 children in each group at 8, 14, 20, 26 and 32 months of age were analysed. Total microbial genomic DNA was isolated from each sample, and PCR-denaturing gradient gel electrophoresis (DGGE) analyses were carried out. The number of bands was significantly higher in the CF group (18.17±4.91 bands) than in the S-ECC group (14.54±5.56 bands) at 32 months of age (Pdiversity. The overall composition of the microbiota is highly similar within an individual over time. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis (DGGE)

    Institute of Scientific and Technical Information of China (English)

    XING; Defeng; REN; Nanqi; GONG; Manli; LI; Jianzheng; LI; Q

    2005-01-01

    To study the structure of microbial communities in the biological hydrogen production reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (CSTR) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gradient gel electrophoresis (DGGE). The results of DGGE demonstrated that an obvious shift of microbial population happened from the beginning of star-up to the 28th day, and the ethanol type fermentation was established. After 28 days the structure of microbial community became stable, and the climax community was formed. Comparative analysis of 16S rDNA sequences from reamplifying and sequencing the prominent bands indicated that the dominant population belonged to low G+C Gram-positive bacteria (Clostridium sp. And Ethanologenbacterium sp.), β- proteobacteria (Acidovorax sp.), γ-proteobacteria (Kluyvera sp.), Bacteroides (uncultured bacterium SJA-168), and Spirochaetes (uncultured eubacterium E1-K13), respectively. The hydrogen production rate increased obviously with the increase of Ethanologenbacterium sp., Clostridium sp. And uncultured Spirochaetes after 21 days, meanwhile the succession of ethanol type fermentation was formed. Throughout the succession the microbial diversity increased however it decreased after 21 days. Some types of Clostridium sp. Acidovorax sp., Kluyvera sp., and Bacteroides were dominant populations during all periods of time. These special populations were essential for the construction of climax community. Hydrogen production efficiency was dependent on both hydrogen producing bacteria and other populations. It implied that the co-metabolism of microbial community played a great role of biohydrogen production in the reactors.

  17. Monitoring of microbial community structure and succession in the biohydrogen production reactor by denaturing gradient gel electrophoresis (DGGE).

    Science.gov (United States)

    Xing, Defeng; Ren, Nanqi; Gong, Manli; Li, Jianzheng; Li, Qiubo

    2005-04-01

    To study the structure of microbial communities in the biological hydrogen production reactor and determine the ecological function of hydrogen producing bacteria, anaerobic sludge was obtained from the continuous stirred tank reactor (CSTR) in different periods of time, and the diversity and dynamics of microbial communities were investigated by denaturing gradient gel electrophoresis (DGGE). The results of DGGE demonstrated that an obvious shift of microbial population happened from the beginning of star-up to the 28th day, and the ethanol type fermentation was established. After 28 days the structure of microbial community became stable, and the climax community was formed. Comparative analysis of 16S rDNA sequences from reamplifying and sequencing the prominent bands indicated that the dominant population belonged to low G+C Gram-positive bacteria (Clostridium sp. and Ethanologenbacterium sp.), beta-proteobacteria (Acidovorax sp.), gamma-proteobacteria (Kluyvera sp.), Bacteroides (uncultured bacterium SJA-168), and Spirochaetes (uncultured eubacterium E1-K13), respectively. The hydrogen production rate increased obviously with the increase of Ethanologenbacterium sp., Clostridium sp. and uncultured Spirochaetes after 21 days, meanwhile the succession of ethanol type fermentation was formed. Throughout the succession the microbial diversity increased however it decreased after 21 days. Some types of Clostridium sp. Acidovorax sp., Kluyvera sp., and Bacteroides were dominant populations during all periods of time. These special populations were essential for the construction of climax community. Hydrogen production efficiency was dependent on both hydrogen producing bacteria and other populations. It implied that the co-metabolism of microbial community played a great role of biohydrogen production in the reactors.

  18. 磷脂脂肪酸谱图分析方法及其在环境微生物学领域的应用%Applications of Phospholipid Fatty Acid (PLFA) Analysis in Environmental Microbial Study

    Institute of Scientific and Technical Information of China (English)

    李冬梅; 施雪华; 孙丽欣; 赵贞; 余敏; 欧阳红

    2012-01-01

    Traditional microbial identification and cluster analysis method is founded on the basis of the separation of microbial pure culture. Because more than 99% of micro-organisms can not be cultured in the natural environment, microbial analysis and research have many limitations. Compared with the traditional medium-based microbial separation technology as well as physiological methods and molecular biological methods, the Phospholipid Fatty Acid analysis which based on fatty acids as a biomarker is widely used in the research of environmental microbiology nowadays. This paper discusses the PLFA fingerprint analysis and its applications for environmental microbial studies, including identification of unknown microbes and assessment of microbial diversity.%传统的微生物鉴定和群落分析方法建立在微生物纯种培养分离的基础之上.但是在自然环境中,99% 以上的微生物未能通过人工培养,在微生物的分析和研究中存在很大的局限性.与传统的基于培养基的微生物分离技术以及生理学方法和分子生物学方法相比,基于现代生物化学技术——脂肪酸可作为生物标记物而发展起来的磷脂脂肪酸谱图分析方法(PLFA)具有不依赖于培养体系影响,能够直接有效地提供微生物群落中的信息;脂肪酸成分不受质粒数量的影响,试验结果客观、可靠;试验条件要求低、操作难度小、测试功能多;由脂肪酸谱图可以对整个微生物群落进行定量描述等诸多优点,在环境微生物学领域的应用日趋广泛.本文综述了PLFA谱图分析方法及其在环境微生物学领域的应用,包括在微生物检测、鉴定和微生物多样性研究中的应用.

  19. A PCR-DGGE method for detection and identification of Campylobacter, Helicobacter, Arcobacter and related Epsilobacteria and its application to saliva samples from humans and domestic pets

    DEFF Research Database (Denmark)

    Petersen, Randi Føns; Harrington, C. S.; Kortegaard, H. E.

    2007-01-01

    distinguished. This approach detected Epsilobacteria in all saliva samples collected from humans, cats and dogs, and identified Campylobacter concisus and/or Campylobacter gracilis in the human samples. The pet animal samples were taken from individuals with oral/dental diseases; PCR-DGGE identified up to four...

  20. 16S rRNA gene-based identification of bacteria in postoperative endophthalmitis by PCR-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) fingerprinting

    OpenAIRE

    Yendi Navarro-Noya; César Hernández-Rodríguez; Zenteno, Juan C.; Beatriz Buentello-Volante; Cancino-Díaz, Mario E.; Janet Jan-Roblero; Juan C. Cancino-Díaz

    2012-01-01

    Conventional microbiological culture techniques are frequently insufficient to confirm endophthalmitis clinical cases which could require urgent medical attention because it could lead to permanent vision loss. We are proposing PCR-DGGE and 16S rRNA gene libraries as an alternative to improve the detection and identification rate of bacterial species from endophthalmitis cases.

  1. Predominant Bacillus spp. in agricultural soil under different management regimes detected via PCR-DGGE

    NARCIS (Netherlands)

    Garbeva, P.; Veen, van J.A.; Elsas, van J.D.

    2003-01-01

    A PCR system for studying the diversity of species of Bacillus and related taxa directly from soil was developed. For this purpose, a specific 24-bp forward primer located around position 110 of the 16S ribosomal RNA gene was designed and combined with a reverse bacterial primer located at the end

  2. Intestinal microbial community diversity in neonatal necrotizing enterocolitis analyzed by PCR-DGGE%PCR-DGGE对新生儿坏死性小肠结肠炎肠道菌落结构及其动态性研究

    Institute of Scientific and Technical Information of China (English)

    郑树芳; 徐艳珍; 艾青; 余加林

    2012-01-01

    目的 探讨新生儿坏死性小肠结肠炎(NEC)患儿肠道菌落的结构和动态性变化.方法 从NEC疾病组(n=16例)及对照组(n=16例)的新生儿连续不同时间段的粪便提取肠道细菌总DNA,用357F-GC/518R引物扩增16S rDNA 的V3可变区,结合变性梯度凝胶电泳(DGGE)技术分析.结果 NEC组与对照组比较,肠道细菌菌落的Shannon指数相对较高(P<0.05),分布不均,波动明显,细菌的多样性高于对照组,细菌菌落多样性特征存在一定的差异.NEC组的Shannon指数在发病初期明显增多,随着疾病的治疗与恢复,呈先降后升的趋势(Shannon指数从大于或等于50降至小于或等于30以下然后波动回升至35左右),DGGE胶回收测序显示新生儿肠道优势菌群以肺炎克雷伯杆菌属、大肠埃希菌、肠球菌为主,NEC组与对照组细菌种类没有明显的区别,存在数量上的差异,显示了DGGE技术的优越性.结论 NEC患儿的肠道菌群失衡可能是NEC发病细菌感染的重要因素.%Objective To analysis intestinal bacterial community composition and dynamics of change in neonatal necrotizing en-terocolitis(NEC). Methods Total DNA of fecal intestinal bacteria was directly extracted from NEC diseases(n = 16) and the control group(n=16) of newborns continuously at different times using the 357F-GC and 518R primers amplified V3 variable region of the 16S rRNA gene,combined with denaturing gradient gel electrophoresis(DGGE). Results The NEC group compared with the control group,Shannon index of intestinal bacterial was relatively higher(P<0. 05) ,the uneven distribution of apparent fluctuations in the diversity of bacteria was higher than the control, there were some differences of bacterial colony diversity characteristics. Shannon index of NEC group increased significantly in the early stage, was down then up trend with the treatment of the disease and recovery (The Shannon index from ≥ 50 to ≤ 30 down and slowly rose to about 35) ,and

  3. Plankton community composition in the Three Gorges Reservoir Region revealed by PCR-DGGE and its relationships with environmental factors

    Institute of Scientific and Technical Information of China (English)

    YAN Qingyun; YU Yuhe; FENG Weisong; YU Zhigang; CHEN Hongtao

    2008-01-01

    To explore the relationships between community composition and the environment in a reservoir ecosystem,plankton communities from the Three Gorges Reservoir Region were studied by PCR-denaturing gradient gel electrophoresis fingerprinting.Bacterial and eukaryotic operational taxonomic units(OTUs),generated by DGGE analysis of the PCR-amplified 16S and 18S rRNA genes,were used as surrogates for the dominant "biodiversity units".OTU composition among the sites was heterogeneous;46.7% of the total bacterial OTUs (45)and 64.1% of the eukaryotic OTUs (39) were identified in less than half of the sampling sites.Unweighted pair group method with arithmetic averages (UPGMA) clustering of the OTUs suggested that the plankton communities in the Xiangxi Rive sites were not always significantly different from those from the Yangtze River sites,despite clear difierences in their environmental characterizations.Canonical correspondence analysis (CCA) Was applied to further investigate the relationships between OTU composition and the environmental factors.The first two CCA ordination axes suggested that the bacterial community composition was primadly correlated with the variables of NO3--N,dissolved oxygen (DO),and SiO32--Si,whereas,the eukaryotic community was mainly correlated with the concentrations of DO, PO43--P, and SiO32--Si.

  4. RT-PCR–DGGE Analysis to Elucidate the Dominant Bacterial Species of Industrial Spanish-Style Green Table Olive Fermentations

    Science.gov (United States)

    Benítez-Cabello, Antonio; Bautista-Gallego, Joaquín; Garrido-Fernández, Antonio; Rantsiou, Kalliopi; Cocolin, Luca; Jiménez-Díaz, Rufino; Arroyo-López, Francisco N.

    2016-01-01

    This paper describes the dominant bacterial species metabolically active through the industrial production of Spanish-style Manzanilla and Gordal olives. For this purpose, samples (brines and fruits) obtained at 0, 15, and 90 fermentation days were analyzed by a culture-independent approach to determine viable cells by reverse transcription of RNA and further PCR-DGGE analysis, detecting at least 7 different species. Vibrio vulnificus, Lactobacillus plantarum group, and Lactobacillus parafarraginis were present in samples from both cultivars; Lactobacillus sanfranciscensis and Halolactobacillus halophilus were detected only in Gordal samples, while Staphylococcus sp. was exclusively found at the onset of Manzanilla fermentations. Physicochemical data showed a typical fermentation profile while scanning electron microscopy confirmed the in situ biofilm formation on the olive epidermis. Different Bacillus, Staphylococcus, and Enterococcus species, not detected during the fermentation process, were also found in the solid marine salt used by the industry for preparation of brines. Elucidation of these non-lactic acid bacteria species role during fermentation is then an appealingly challenge, particularly regarding safety issues. PMID:27582739

  5. Denaturing gradient gel electrophoresis (DGGE as a powerful novel alternative for differentiation of epizootic ISA virus variants.

    Directory of Open Access Journals (Sweden)

    Marisela Carmona

    Full Text Available Infectious Salmon Anemia is a devastating disease critically affecting world-wide salmon production. Chile has been particularly stricken by this disease which in all cases has been directly related with its causative agent, a novel orthomyxovirus which presents specific and distinctive infective features. Among these, two molecular markers have been directly associated with pathogenicity in two of the eight RNA sub genomic coding units of the virus: an insertion hot spot region present in viral segment 5 and a Highly Polymorphic Region (HPR located in viral segment 6. Here we report the successful adaptation of a PCR-dependent denaturing gel electrophoresis technique (DGGE, which enables differentiation of selected reported HPR epizootic variants detected in Chile. At the same time, the technique allows us to distinguish one nucleotide differences in sequences associated with the intriguing, and still not well-understood, insertion events which tend to occur on RNA Segment 5. Thus, the versatility of the technique opens new opportunities for improved understanding of the complex biology of all ISA variants as well as possible applications to other highly variable pathogens.

  6. DGGE and real-time PCR analysis of lactic acid bacteria in bacterial communities of the phyllosphere of lettuce.

    Science.gov (United States)

    Zwielehner, Jutta; Handschur, Michael; Michaelsen, Astrid; Irez, Selen; Demel, Michael; Denner, Ewald B M; Haslberger, Alexander G

    2008-05-01

    Food associated indigenous microbial communities exert antagonistic effects on pathogens and may routinely deliver health relevant microorganisms to the GI tract. By using molecular, culture independent methods including PCR-DGGE of 16S rDNA-coding regions and real-time PCR (RT-PCR) as well as BIOLOG metabolic fingerprinting, microbial communities on lettuce were analyzed in samples from fields, from supermarkets and soil. Amplified 16S rRNA gene sequences (57.7%) could be assigned to species previously reported as typical for the phyllosphere including Pantoea agglomerans, Pseudomonas flavescens, Moraxella spp., and Mycobacterium spp. 71.8% of the sequences obtained represented so far undescribed taxa. Principal component analysis of BIOLOG metabolic profiles indicated a seasonal variation in the lettuce phyllosphere microbial community structure. Various lactic acid bacteria were detected including several Lactobacillus and Leuconostoc species in particular on lettuce from organic farming. By RT-PCR lactobacilli were found with a range of abundances from 1x10(4 )to 1x10(5 )copies/g lettuce. Considering the importance of salad in many diets lettuce may contribute to a constant supply with LAB.

  7. Bacterial Community Structure in a Mollisol Under Long-Term Natural Restoration, Cropping, and Bare Fallow History Estimated by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    WANG Guang-Hua; JIN Jian; LIU Jun-Jie; CHEN Xue-Li; LIU Ju-Dong; LIU Xiao-Bing

    2009-01-01

    Soil microbial biomass and community structures are commonly used as indicators for soil quality and fertility.A investigation was performed to study the effects of long-term natural restoration,cropping,and bare fallow managements on the soil microbial biomass and bacterial community structures in depths of 0-10,20-30,and 40-50 cm in a black soil (Mollisol).Microbial biomass was estimated from chloroform fumigation-extraction,and bacterial community structures were determined by analysis of 16S rDNA using polymerase chain reaction-denaturing gradient gel electrophoresis (PCRDGGE).Experimental results showed that microbial biomass significantly declined with soil depth in the managements of restoration and cropping,but not in the bare fallow.DGGE profiles indicated that the band number in top 0-10 cm soils was less than that in depth of 20-30 or 40-50 cm.These suggested that the microbial population was high but the bacterial community structure was simple in the topsoil.Cluster and principle component analysis based on DGGE banding patterns showed that the bacterial community structure was affected by soil depth more primarily than by managements,and the succession of bacterial community as increase of soil depth has a similar tendency in the three managements.Fourteen predominating DGGE bands were excised and sequenced,in which 6 bands were identified as the taxa of Verrucomicrobia,2 bands as Actinobacteria,2 bands as α-Proteobacteria,and the other 4 bands as δ-Proteobacteria,Acidobacteria,Nitrospira,and unclassified bacteria.In addition,the sequences of 11 DGGE bands were closely related to uncultured bacteria.Thus,the bacterial community structure in black soil was stable,and the predominating bacterial groups were uncultured.

  8. Succession of methanogenic archaea in rice straw incorporated into a Japanese rice field: estimation by PCR-DGGE and sequence analyses

    Directory of Open Access Journals (Sweden)

    Atsuo Sugano

    2005-01-01

    Full Text Available The succession and phylogenetic profiles of methanogenic archaeal communities associated with rice straw decomposition in rice-field soil were studied by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE analysis followed by 16S rDNA sequencing. Nylon bags containing either leaf sheaths or blades were buried in the plowed layer of a Japanese rice field under drained conditions during the off-crop season and under flooded conditions after transplanting. In addition, rice straw samples that had been buried in the rice field under drained conditions during the off-crop season were temporarily removed during spring plowing and then re-buried in the same rice field under flooded conditions at transplanting. Populations of methanogenic archaea were examined by amplification of the 16S rRNA genes in the DNA extracted from the rice straw samples. No PCR product was produced for samples of leaf sheath or blade prior to burial or after burial under drained conditions, indicating that the methanogen population was very small during decomposition of rice straw under oxic conditions. Many common bands were observed in rice straw samples of leaf sheath and blade during decomposition of rice straw under flooded conditions. Cluster analysis based on DGGE patterns divided methanogenic archaeal communities into two groups before and after the mid-season drainage. Sequence analysis of DGGE bands that were commonly present were closely related to Methanomicrobiales and Rice cluster I. Methanomicrobiales, Rice cluster I and Methanosarcinales were major members before the mid-season drainage, whereas the DGGE bands that characterized methanogenic archaeal communities after the mid-season drainage were closely related to Methanomicrobiales. These results indicate that mid-season drainage affected the methanogenic archaeal communities irrespective of their location on rice straw (sheath and blade and the previous history of decomposition

  9. 利用DGGE-菌落原位杂交法分离土壤中精喹禾灵降解菌%Isolation of Quizalofop-p-ethyl-degrading Bacteria from Soil by DGGE-Colony in situ Hybridization

    Institute of Scientific and Technical Information of China (English)

    吕欣; 彭霞薇; 呼庆; 马安周; 江泽平; 魏远

    2013-01-01

    Naturally occurring bacteria isolates capable of metabolizing pesticides have received considerable attention because they offer the possibility of both environmentally friendly and in situ remediation. The effect of herbicide quizalofop-p-ethyl on bacterial community in soil was analyzed using the technique of PCR-DGGE for isolating strains biodegrading quizalofop-p-ethyl. Results indicated that the soil bacterial community structures significantly changed after adding quizalofop-p-ethyl. The bacterial diversity of soil showed an increasing-decreasing-increasing trend. The largest changes occurred in the 9th day and then became stabilized. According to the sequencing results of bands in DGGE profiles, it inferred that members of bacterial genera Pseudomonas, Massilia and Burkholderia had tolerance to quizalofop-p-ethyl, and the potential for degradation. These microbial groups could be used to isolate and screen as the indigenous microbial resources to reduce pesticide residues. Digoxigenin-labeled probes had been synthesized based on the sequencing results of bands in the DGGE profiles, and three bacterial strains capable of biodegrading quizalofop-p-ethyl were isolated from soil by colony in situ hybridization technique. The strain named LI was able to utilize quizalofop-p-ethyl as the sole source of carbon. The strain was identified as Pseudomonas sp., based on the phylogenetic analysis of 16S rRNA. The degrading ability of strain L1 in minimal medium with quizalofop-p-ethyl was investigated by HPLC. The quizalofop-p-ethyl content decreased by almost 50% after 7 days, and the biomass of strain L1 increased while the content of quizalofop-p-ethyl was decreased. This confirmed that the strain L1 had the capacity of degradation. This result provided a basis for future research on degradation mechanism and functional genes.%从自然环境中分离到的可降解农药的土著微生物,因其对环境的友好性及原位修复的可行性,受到了高度关注.

  10. Perkinsus olseni and P. chesapeaki detected in a survey of perkinsosis of various clam species in Galicia (NW Spain) using PCR-DGGE as a screening tool.

    Science.gov (United States)

    Ramilo, Andrea; Pintado, José; Villalba, Antonio; Abollo, Elvira

    2016-01-01

    A survey on perkinsosis was performed involving 15 locations scattered along the Galician coast (NW Spain) and four clam species with high market value (Ruditapes decussatus, Ruditapes philippinarum, Venerupis corrugata and Polititapes rhomboides). The prevalence of Perkinsus parasites was estimated by PCR using genus-specific primers. The highest percentage of PCR-positive cases for perkinsosis corresponded to clams R. decussatus and V. corrugata, while lower values were detected in R. philippinarum and no case was found in P. rhomboides. The discrimination of Perkinsus species was performed by PCR-RFLP and by a new PCR-DGGE method developed in this study. Perkinsus olseni was identified in every clam species, except in P. rhomboides, using both PCR-DGGE and PCR-RFLP. Additionally, Perkinsus chesapeaki was only detected by PCR-DGGE infecting two Manila clams R. philippinarum from the same location, reporting the first case in Galicia. P. chesapeaki identification was further confirmed by in situ hybridisation assay and phylogenetic analysis of ITS region and LSU rDNA.

  11. 发酵乳中双岐杆菌种类快速识别%Rapid identification bifidobacterium in fermented milk products by PCR-DGGE analysis

    Institute of Scientific and Technical Information of China (English)

    王立平; 吴艳涛; 刘晓莉; 曹悦

    2012-01-01

    To establish a rapid identification method for bifidobacterium in fermented milk products.The use of Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis(PCR-DGGE) technique in identifying bifidobacterium present in commercial probiotic yoghurts dealed with pronase E was evaluated.Identification was achieved comparing the PCR-DGGE patterns obtained from the analysed products with the ladder bands.PCR-DGGE assays enabled identification of the species of bifidobacterium initially present in commercial fermented milk products and their accurate quantification with a detection threshold of 105 cells per mL of product.Established PCR-DGGE analysis method is situble for detection of bifidobacterium in commercial probiotic yoghurts.%建立发酵乳制品中双歧杆菌快速识别方法。采用酶解前处理法获取样品中菌体细胞,基于PCR-DGGE技术确定发酵乳中双歧杆菌种属。该方法能准确、快速鉴别双歧杆菌,检出限为105cfu/mL。该方法可用于发酵乳中双歧杆菌的准确识别。

  12. Phytoplankton diversity in the East China Sea and Yellow Sea measured by PCR-DGGE and its relationships with environmental factors

    Science.gov (United States)

    Sun, Jing; Yu, Zhigang; Gao, Yahui; Zhou, Qianqian; Zhen, Yu; Chen, Hongtao; Zhao, Liyuan; Yao, Qingzhen; Mi, Tiezhu

    2010-03-01

    Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversity of phytoplankton was characterized using cultivation-independent PCR-based denaturing gradient gel electrophoresis (DGGE). Groups resulting from unweighted pair-group method with arithmetic averages clustering of the DGGE profiles showed good consistency with the eco-environmental characteristics of the sea area they belonged to. Additionally, the clustering results based on DGGE fingerprinting and those based on morphological compositions were practically identical. The relationship of phytoplankton diversity to environmental factors was statistically analyzed. Temperature, dissolved inorganic nitrogen (DIN), and silicate-Si were found significantly related to the phytoplankton community composition. Canonical correspondence analysis (CCA) was performed to reveal the relationship between community composition and these three environmental factors. Generally, values of the ECS are clearly separated from those of the YS in the CCA biplot, due to mainly the effect of temperature and DIN.

  13. Changes in the composition of the bacterial flora on tray-packaged pork during chilled storage analyzed by PCR-DGGE and real-time PCR.

    Science.gov (United States)

    Jiang, Yun; Gao, Feng; Xu, XingLian; Ye, KePing; Zhou, GuangHong

    2011-01-01

    In this study, a polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) was used to investigate the changes in the composition of the bacterial population of tray-packaged pork during chilled storage. Relative quantitative real-time PCR was further used to evaluate the predominant spoilage bacteria obtained from DGGE analysis for their relative amount to the total bacteria in meat samples. DGGE analysis of the V3 and V6-V8 regions of the 16S rRNA gene showed that Pseudomonas were the predominant bacterial species at the end of the monitoring period. Real-time PCR expressed as the ΔΔC(T) method showed that the average 2(-ΔΔC)(T) values increased continually during the storage period from less than 0.001 at day 0 to 4.438 at the end of the monitoring, which indicated that the proportions of Pseudomonas within the total bacteria in meat samples increased. Both methods confirmed that Pseudomonas was the predominant spoilage bacteria. Practical Application: This study uses new techniques to identify bacteria in fresh retail pork and to follow changes in the bacterial population during 12 d refrigerated storage. Pseudomonads were found to increase with storage time, becoming the dominant flora after 12 d.

  14. PCR-DGGE法分析婴儿肠道菌群多样性%Diversity analysis of infant intestinal microflora by using PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    费鹏; 白洪健; 程述震; 曹飞扬; 郭鸰; 姜亦超; 苑秀娟; 江岩

    2013-01-01

    利用PCR-DGGE技术探究婴儿肠道菌群的多样性,为益生菌在婴儿配方乳粉中的应用提供理论依据.采用细菌的16S rDNA V3区通用引物,以15例食源性腹泻婴儿和15例健康婴儿粪便样本的总DNA为模板,PCR扩增后进行变形梯度凝胶电泳(DGGE)分析.结果表明:30份粪便样本的DGGE图谱均表现为高度多态性.食源性腹泻婴儿肠道菌群多样性与健康组婴儿肠道菌群多样性有明显差异,且食源性腹泻婴儿肠道菌群多样性较低.通过聚类分析和相似度分析,可以得出食源性腹泻婴儿的肠道菌群有高度的相似性,与健康婴儿的肠道菌群有明显的差异.PCR-DGGE技术可以初步分析婴儿肠道菌群的多样性,进而为婴儿配方乳粉的研制提供理论依据.%Purpose: The diversity of the infant intestinal microflora was analyzed by using the PCR-DGGE, providing theoretical basis for the application of probiotics in infant formula milk powder. Method: The universal primer of the bacterial 16S rDNA-V3 region was used as primer and the total DNA of food-bome diarrhea infants and health infants stool samples were used as a template. After PCR amplification, DGGE analysis was performed. Result: The DGGE profiles of the 30 stool samples were highly polymorphic. The diversity of the food-borne diarrhea infants was significantly different with healthy infants, and the Food-bome diarrhea infants had a lower intestinal diversity. By cluster analysis and similarity analysis, Can be drawn that the similarity of intestinal microflora of food-borne diarrhea infants was higher, and the intestinal microflora of food-bome diarrhea infants and healthy infants had obvious differences. Conclusion: PCR-DGGE technology can preliminary analyze the diversity of the infant intestinal microflora, providing theoretical basis for the application of probiotics in infant formula milk powder.

  15. PCR-DGGE

    African Journals Online (AJOL)

    Jane

    2011-05-23

    May 23, 2011 ... 1State Key Laboratory of Food Science and Technology, Nanchang, Jiangxi, 330047, China. 2Jiangxi-OAI Joint ... LAB, lactic acid bacteria; MRS, Man, Rogosa and Sharpe; YPD, yeast peptone .... thermophilusG1 (L1) also verified the high specific of ..... Inhibition and facilitation of nucleic acid amplification.

  16. Effect of Nitrogen Deposition on Soil Microbial Community Structure Determined with the PLFA Method%应用PLFA方法分析氮沉降对土壤微生物群落结构的影响

    Institute of Scientific and Technical Information of China (English)

    刘彩霞; 焦如珍; 董玉红; 孙启武; 刘少文

    2015-01-01

    Objective]Soil microbial community is a sensitive indicator of changes in soil quality and soil ecosystem. The changes in soil microbe community structure in response to simulated nitrogen deposition were investigated by phospholipids fatty acids ( PLFA) biomarkers. This study can be accurate to understand the effects of short-term nitrogen deposition on soil ecosystem,and hence predict the change of soil properties and plant growth. This study aims at providing microbial parameters and indicators for the sustainable management of artificial forest under nitrogen saturation condition,and would have guiding significance for the real-time control and governance of nitrogen deposition.[Method]In May 2013,we established 30 plots of 1 m × 1 m in a hectare of young Chinese fir forest,at the Shanxia forest farm in Fenyi,Jiangxi Province. Nitrogen loadings were designed at 5 levels such as N0,N1,N2,N3 and N4 at the doses of 0, 20,40,60 and 80 kg N·hm - 2 a - 1,respectively,with 2 nitrogen forms of NH4+-N (I) and NO3--N (II). After one year treatment,soil samples were collected with a soil drill. The fatty acid phospholipid was extracted with potassium hydroxide-methyl methanol solution,and assayed by Agilent 6850N with nineteen alkyl acid as internal standard. PLFA pattern was analyzed with the Sherlock MIS4. 5 system,before the fatty acid content was converted into the number of nmol·g -1 dry soil. [Result]A total of 72 PLFAs were detected,and among them the characteristic fatty acids were 36 kinds. The analysis on type and content of the characteristic fatty acids indicated that prokaryotic microorganism was the predominant group in the plot soil treated with all nitrogen treatments. In different nitrogen treatment plots,the range of soil microbial biomass with characteristics of total PLFAs content was 20 -44 nmol·g -1 . In deposition of ammonium nitrogen,the amount of total PLFAs,Gram-positive bacterial PLFAs and Gram-negative bacterial PLFAs in the soil were

  17. Application of PCR-denaturing-gradient gel electrophoresis (DGGE) method to examine microbial community structure in asparagus fields with growth inhibition due to continuous cropping.

    Science.gov (United States)

    Urashima, Yasufumi; Sonoda, Takahiro; Fujita, Yuko; Uragami, Atsuko

    2012-01-01

    Growth inhibition due to continuous cropping of asparagus is a major problem; the yield of asparagus in replanted fields is low compared to that in new fields, and missing plants occur among young seedlings. Although soil-borne disease and allelochemicals are considered to be involved in this effect, this is still controversial. We aimed to develop a technique for the biological field diagnosis of growth inhibition due to continuous cropping. Therefore, in this study, fungal community structure and Fusarium community structure in continuously cropped fields of asparagus were analyzed by polymerase chain reaction/denaturing-gradient gel electrophoresis (PCR-DGGE). Soil samples were collected from the Aizu region of Fukushima Prefecture, Japan. Soil samples were taken from both continuously cropped fields of asparagus with growth inhibition and healthy neighboring fields of asparagus. The soil samples were collected from the fields of 5 sets in 2008 and 4 sets in 2009. We were able to distinguish between pathogenic and non-pathogenic Fusarium by using Alfie1 and Alfie2GC as the second PCR primers and PCR-DGGE. Fungal community structure was not greatly involved in the growth inhibition of asparagus due to continuous cropping. By contrast, the band ratios of Fusarium oxysporum f. sp. asparagi in growth-inhibited fields were higher than those in neighboring healthy fields. In addition, there was a positive correlation between the band ratios of Fusarium oxysporum f. sp. asparagi and the ratios of missing asparagus plants. We showed the potential of biological field diagnosis of growth inhibition due to continuous cropping of asparagus using PCR-DGGE.

  18. Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

    Institute of Scientific and Technical Information of China (English)

    LIU Xin-chun; ZHANG Yu; YANG Min; WANG Zhen-yu; LV Wen-zhou

    2007-01-01

    The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis (DGGE) of nested polymerase chain reaction (nested PCR) amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria (AOB) species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.

  19. Diversity of thermophilic bacteria in raw, pasteurized and selectively-cultured milk, as assessed by culturing, PCR-DGGE and pyrosequencing.

    Science.gov (United States)

    Delgado, Susana; Rachid, Caio T C C; Fernández, Elena; Rychlik, Tomasz; Alegría, Angel; Peixoto, Raquel S; Mayo, Baltasar

    2013-10-01

    Thermophilic lactic acid bacteria (LAB) species, such as Streptococcus thermophilus, Lactobacillus delbrueckii and Lactobacillus helveticus, enjoy worldwide economic importance as dairy starters. To assess the diversity of thermophilic bacteria in milk, milk samples were enriched in thermophilic organisms through a stepwise procedure which included pasteurization of milk at 63 °C for 30 min (PM samples) and pasteurization followed by incubation at 42 °C for 24 h (IPM samples). The microbial composition of these samples was analyzed by culture-dependent (at 42 °C) and culture-independent (PCR-DGGE and pyrosequencing of 16S rRNA gene amplicons) microbial techniques. The results were then compared to those obtained for their corresponding starting raw milk counterparts (RM samples). Twenty different species were scored by culturing among 352 isolates purified from the counting plates and identified by molecular methods. Mesophilic LAB species (Lactococcus lactis, Lactococcus garvieae) were dominant (87% of the isolates) among the RM samples. However, S. thermophilus and Lb. delbrueckii were found to be the dominant recoverable organisms in both PM and IPM samples. The DGGE profiles of RM and PM samples were found to be very similar; the most prominent bands belonging to Lactococcus, Leuconostoc and Streptococcus species. In contrast, just three DGGE bands were obtained for IPM samples, two of which were assigned to S. thermophilus. The pyrosequencing results scored 95 operational taxonomic units (OTUs) at 3% sequence divergence in an RM sample, while only 13 were encountered in two IPM samples. This technique identified Leuconostoc citreum as the dominant microorganism in the RM sample, while S. thermophilus constituted more than 98% of the reads in the IPM samples. The procedure followed in this study allowed to estimate the bacterial diversity in milk and afford a suitable strategy for the isolation of new thermophilic LAB strains, among which adequate

  20. Deterioration to extinction of wastewater bacteria by non-thermal atmospheric pressure air plasma as assessed by 16S rDNA-DGGE fingerprinting

    Directory of Open Access Journals (Sweden)

    Wael Samir El-Sayed

    2015-10-01

    Full Text Available The impact of cold atmospheric plasma on the bacterial community structure of wastewater from two different industries was investigated by metagenomic-based PCR-DGGE utilizing 16S rRNA genes. Three doses of atmospheric pressure dielectric barrier discharge plasma were applied to wastewater samples on different time scales. DGGE revealed that the bacterial community gradually changed and overall abundance decreased to extinction upon plasma treatment. The bacterial community in food processing wastewater contained 11 key operational taxonomic units that remained almost completely unchanged when exposed to plasma irradiation at 75.5 mA for 30 or 60s. However, when exposure time was extended to 90s, only Escherichia coli, Coliforms, Aeromonas sp., Vibrio sp., and Pseudomonas putida survived. Only E. coli, Aeromonas sp., Vibrio sp. and P. putida survived treatment at 81.94 mA for 90s. Conversely, all bacterial groups were completely eliminated by treatment at 85.34 mA for either 60 or 90s. Dominant bacterial groups in leather processing wastewater also changed greatly upon exposure to plasma at 75.5 mA for 30 or 60s, with Enterobacter aerogenes, Klebsiella sp., Pseudomonas stutzeri and Acidithiobacillus ferrooxidans being sensitive to and eliminated from the community. At 90s of exposure, all groups were affected except for Pseudomonas sp. and Citrobacter freundii.

  1. Application of real-time PCR, DGGE fingerprinting, and culture-based method to evaluate the effectiveness of intrinsic bioremediation on the control of petroleum-hydrocarbon plume.

    Science.gov (United States)

    Kao, Chih-Ming; Chen, Colin S; Tsa, Fu-Yu; Yang, Kai-Hsing; Chien, Chih-Ching; Liang, Shih-Hsiung; Yang, Chin-an; Chen, Ssu Ching

    2010-06-15

    Real-time polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and the culture-based method were applied in the intrinsic bioremediation study at a petroleum-hydrocarbon contaminated site. The genes of phenol hydroxylase (PHE), ring-hydroxylating toluene monooxygenase (RMO), naphthalene dioxygenase (NAH), toluene monooxygenase (TOL), toluene dioxygenase (TOD), and biphenyl dioxygenase (BPH4) were quantified by real-time PCR. Results show that PHE gene was detected in groundwater contaminated with benzene, toluene, ethylbenzene, xylene isomers (BTEX) and methyl tert-butyl ether (MTBE), and this indicates that intrinsic bioremediation occurred at this contaminated site. Results from DGGE analyses reveal that the petroleum-hydrocarbon plume caused the variation in microbial communities. In this study, MTBE degraders including Pseudomonas sp. NKNU01, Bacillus sp. NKNU01, Klebsiella sp. NKNU01, Enterobacter sp. NKNU01, and Enterobacter sp. NKNU02 were isolated from the contaminated groundwater using the cultured-based method. Results from MTBE biodegradation experiment show that the isolated bacteria were affected by propane. This indicates that propane may influence the metabolic pathway of MTBE by these bacteria. Knowledge and comprehension obtained from this study will be helpful in evaluating the occurrence and effectiveness of intrinsic bioremediation on the remediation of petroleum-hydrocarbon contaminated groundwater.

  2. Comparison of bacterial community structures of terrestrial cyanobacterium Nostoc flagelliforme in three different regions of China using PCR-DGGE analysis.

    Science.gov (United States)

    Han, Pei-pei; Shen, Shi-gang; Jia, Shi-ru; Wang, Hui-yan; Zhong, Cheng; Tan, Zhi-lei; Lv, He-xin

    2015-07-01

    Filamentous Nostoc flagelliforme form colloidal complex, with beaded cells interacting with other bacteria embedded in the complex multilayer sheath. However, the species of bacteria in the sheath and the interaction between N. flagelliforme and associated bacteria remain unclear. In this study, PCR-denaturing gradient gel electrophoresis (DGGE) was used to investigate the bacterial communities of N. flagelliforme from three regions of China. DGGE patterns showed variations in all samples, exhibiting 25 discrete bands with various intensities. The diversity index analysis of bands profiles suggested the high similarity of bacterial communities to each other but also the dependence of microbial composition on each location. Phylogenetic affiliation indicated that the majority of the sequences obtained were affiliated with Actinobacteria, Cyanobacteria, Proteobacteria, Acidobacteria, Bacteroidetes, of which Cyanobacteria was dominant, followed the Proteobacteria. Members of the genus Nostoc were the most abundant in all samples. Rhizobiales and Actinobacteria were identified, whereas, Craurococcus, Caulobacter, Pseudomonas, Terriglobus and Mucilaginibacter were also identified at low levels. Through comparing the bacterial composition of N. flagelliforme from different regions, it was revealed that N. flagelliforme could facilitate the growth of other microorganisms including both autotrophic bacteria and heterotrophic ones and positively contributed to their harsh ecosystems. The results indicated N. flagelliforme played an important role in diversifying the microbial community composition and had potential application in soil desertification.

  3. Monitoring microbial community structure and succession of an A/O SBR during start-up period using PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    WANG Xiuheng; ZHANG Kun; REN Nanqi; LI Nan; REN Lijiao

    2009-01-01

    Polymerase chain reaction (PCR) - denaturing gradient gel electrophoresis (DGGE) protocol was employed for revealing microbial community structure and succession in a sequential anaerobic and aerobic reactor performing enhanced biological phosphorus removal (EBPR) during start-up period.High phosphorus removal was achieved after 15 d.On day 30, phosphorus removal efficiency reached to 83.2% and the start-up was finished.DGGE profiles of periodical sludge samples showed that dominant microbial species were 19 OTUs (operational taxonomy unit ).Unweighted pair-group method using Arithmetic averages (UPGMA clustering analysis revealed that rapid community succession correlated to lower phosphorus removal rate and higher phosphorus removal efficiency reflected on steady community structure.Sequencing results indicated that determined sequences (12 OTUs) belonged to proteobacterium, Actinobacteria, Gemmatimonadales and unaffiliate group.Proteobacterium, Tetrasphaera elongate and Gemmatimonas aurantiaca may act important roles in phosphorus removal.With little amount as known glycogen accumulating organisms, Candidatus Competibacter phosphatis still at accumulating-phase had limited influence on microbial community structure.When climax community was obtained, dominant microbes were 14 OTUs.Microbes in a large amount were uncultured bacterium, Thauera sp., uncultured γ-Proteobacterium and Tetrasphaera elongata.

  4. Cyanobacterial diversity shifts induced by butachlor in selected Indian rice fields in Eastern Uttar Pradesh and Western Bihar analyzed with PCR and DGGE.

    Science.gov (United States)

    Kumari, Nidhi; Narayan, Om Prakash; Rai, Lal Chand

    2012-01-01

    The present study examines the effects of 30 mg/kg butachlor on the cyanobacterial diversity of rice fields in Eastern Uttar Pradesh and Western Bihar in India. A total of 40 samples were grouped into three classes [(i) acidic, (ii) neutral, and (iii) alkaline soils], based on physicochemical and principle component analyses. Acidic soils mainly harbored Westillopsis, Trichormus, Anabaenopsis, and unicellular cyanobacteria; whereas Nostoc, Anabaena, Calothrix, Tolypothrix, and Aulosira were found in neutral and alkaline soils. Molecular characterization using 16S rRNA PCR and DGGE revealed the presence of 13 different phylotypes of cyanobacteria in these samples. Butachlor treatment of the soil samples led to the disappearance of 5 and the emergence of 2 additional phylotypes. A total of 40 DGGE bands showed significant reproducible changes upon treatment with butachlor. Phylogenetic analyses divided the phylotypes into five major clusters exhibiting interesting links with soil pH. Aulosira, Anabaena, Trichormus, and Anabaenopsis were sensitive to butachlor treatment, whereas uncultured cyanobacteria, a chroococcalean member, Westillopsis, Nostoc, Calothrix, Tolypothrix, Rivularia, Gloeotrichia, Fischerella, Leptolyngbya, and Cylindrospermum, appeared to be tolerant against butachlor at their native soil pH. Butachlor-induced inhibition of nitrogen fixation was found to be 65% (maximum) and 33% (minimum) in the soil samples of pH 9.23 and 5.20, respectively. In conclusion, low butachlor doses may prove beneficial in paddy fields having a neutral to alkaline soil pH.

  5. Changes in human fecal microbiota due to chemotherapy analyzed by TaqMan-PCR, 454 sequencing and PCR-DGGE fingerprinting.

    Directory of Open Access Journals (Sweden)

    Jutta Zwielehner

    Full Text Available BACKGROUND: We investigated whether chemotherapy with the presence or absence of antibiotics against different kinds of cancer changed the gastrointestinal microbiota. METHODOLOGY/PRINCIPAL FINDINGS: Feces of 17 ambulant patients receiving chemotherapy with or without concomitant antibiotics were analyzed before and after the chemotherapy cycle at four time points in comparison to 17 gender-, age- and lifestyle-matched healthy controls. We targeted 16S rRNA genes of all bacteria, Bacteroides, bifidobacteria, Clostridium cluster IV and XIVa as well as C. difficile with TaqMan qPCR, denaturing gradient gel electrophoresis (DGGE fingerprinting and high-throughput sequencing. After a significant drop in the abundance of microbiota (p = 0.037 following a single treatment the microbiota recovered within a few days. The chemotherapeutical treatment marginally affected the Bacteroides while the Clostridium cluster IV and XIVa were significantly more sensitive to chemotherapy and antibiotic treatment. DGGE fingerprinting showed decreased diversity of Clostridium cluster IV and XIVa in response to chemotherapy with cluster IV diversity being particularly affected by antibiotics. The occurrence of C. difficile in three out of seventeen subjects was accompanied by a decrease in the genera Bifidobacterium, Lactobacillus, Veillonella and Faecalibacterium prausnitzii. Enterococcus faecium increased following chemotherapy. CONCLUSIONS/SIGNIFICANCE: Despite high individual variations, these results suggest that the observed changes in the human gut microbiota may favor colonization with C. difficile and Enterococcus faecium. Perturbed microbiota may be a target for specific mitigation with safe pre- and probiotics.

  6. Effect of biocontrol agent Pseudomonas fluorescens 2P24 on soil fungal community in cucumber rhizosphere using T-RFLP and DGGE.

    Directory of Open Access Journals (Sweden)

    Guanpeng Gao

    Full Text Available Fungi and fungal community play important roles in the soil ecosystem, and the diversity of fungal community could act as natural antagonists of various plant pathogens. Biological control is a promising method to protect plants as chemical pesticides may cause environment pollution. Pseudomonas fluorescens 2P24 had strong inhibitory on Rastonia solanacearum, Fusarium oxysporum and Rhizoctonia solani, etc., and was isolated from the wheat rhizosphere take-all decline soils in Shandong province, China. However, its potential effect on soil fungal community was still unknown. In this study, the gfp-labeled P. fluorescens 2P24 was inoculated into cucumber rhizosphere, and the survival of 2P24 was monitored weekly. The amount decreased from 10(8 to 10(5 CFU/g dry soils. The effect of 2P24 on soil fungal community in cucumber rhizosphere was investigated using T-RFLP and DGGE. In T-RFLP analysis, principle component analysis showed that the soil fungal community was greatly influenced at first, digested with restriction enzyme Hinf I and Taq I. However, there was little difference as digested by different enzymes. DGGE results demonstrated that the soil fungal community was greatly shocked at the beginning, but it recovered slowly with the decline of P. fluorescens 2P24. Four weeks later, there was little difference between the treatment and control. Generally speaking, the effect of P. fluorescens 2P24 on soil fungal community in cucumber rhizosphere was just transient.

  7. Influences of Different DNA Polymerase for Denaturing Gradient Gel Electrophoresis(DGGE)%不同DNA聚合酶对PCR-DGGE技术的影响

    Institute of Scientific and Technical Information of China (English)

    张敏; 蔡俊鹏

    2011-01-01

    [目的]研究不同DNA聚合酶对PCR-DGGE技术的影响.[方法]选用3种不同的DNA聚合酶对单一的7株菌进行PCR扩增,通过DGGE图谱分析探讨不同的DNA聚合酶对PCR-DGGE技术的影响.[结果]用相同的DNA聚合酶1时,上游引物使用357F1比357F2的效果要好.当357F1作为上游引物时,DNA聚合酶2明显好于DNA聚合酶1,但仍有干扰结果出现;当357F2作为上游引物时,使用DNA聚合酶1和DNA聚合酶2都不能使各菌株分离开来.使用高质量的DNA聚合酶3时,上游引物所加入的无论是40 bp还是只有18 bp的"GC"夹,都能够使不同的DNA片段分离开来.[结论]不同的DNA聚合酶对PCR-DGGE技术的影响是很大的,选择合适的DNA聚合酶是至关重要的.%[ Objective ] The research aimed to study the influences of different DNA polymerase for DGGE. [ Method ] 7 strains were PCR amplified by using three different DNA polymerase ,through the analysis of profiles to compare the influence of different DNA polymerase for DGGE.[ Result] When using the same DNA polymerase 1, the effects of forward primer 357F1 was better than 357F2. When the forward primer was 357F1 ,the effects of DNA polymerase 2 was.better DNA polymerase l ,but still had interference. When the forward primer was 357F2,DNA polymerase 1 and DNA polymerase 2 could both separate 7 strains. When high quality DNA polymerase 3 was used,whatever the forward primer was 40 bp and 18 bp GC-clamp the DNA fragment could all be separated. [Conclusion] Different DNA polymerase has big influence on PCR- DGGE,and it is important to selecting suitable DNA polymerase.

  8. [Tracing the Fecal Contamination Sources Based on Bacteroides 16S rRNA PCR- DGGE in Karst Groundwater: Taking Laolongdong Underground River System, Nanshan, Chongqing as an Example].

    Science.gov (United States)

    Zhang, Hong; Jiang, Yong-jun; Zhang, Yuan-zhu; Duan, Yi-fan; Lü, Xian-fu; He, Qiu-fang

    2016-05-15

    Microbial contamination in karst groundwater continually increases and tracing the source researches has become a hot topic for international researchers. In this study, Laolongdong underground river at Nanshan, Chongqing was chosen as an example to adopt filter membrane methods to monitor the fecal microbial contaminations including the total bacterial concentration (TB), the total E. coli concentration (TE), the total fecal coliform (FC) and the total fecal Streptocoocci (FS). Bacteriodes was used as an indicator and PCR-DGGE analysis was used to trace fecal contamination sources in karst groundwater. The results suggested that groundwater in this area was seriously polluted by microbes from feces. The concentrations of microbial parameters exceeded limited levels greatly and the total bacterial amounts ranged 10-2.9 x 10⁷ CFU · mL⁻¹, the concentrations of E. coli were between 4.3-4.0 x 10⁵ CFU · mL⁻¹, the max concentration of FC was 1.1 x 10⁶ CFU · (100 mL)⁻¹ and the max concentration of FS was 1.1 x 10⁵ CFU · (100 mL)⁻¹. The FC/FS ratios were mostly over 2 which suggested that the main fecal source in groundwater was human feces. In addition, PCR-DGGE contrastive analysis of Bacteroides communities showed that the similarities between groundwater samples and human feces were in range of 7. 1% -69. 1% , and the similarity of the groundwater sample from Laolongdong underground river outlet was 69.1% . Bacteroides community similarities between groundwater samples and swine feces were in range of 1.1%-53.4%, and the similarity of Laolongdong underground river outlet was merely 1.5%. The similarity data implied that groundwater contamination resulted mainly from human feces, swine feces contamination composed part of animals' fecal contamination, and other animals' feces participated too. Furthermore, sequencing results of PCR-DGGE products revealed that most Bacteroides in groundwater originated from human intestinal tract and human feces.

  9. Review of Different DNA Extraction Methods in PCR-DGGE Technique%PCR-DGGE技术中不同DNA提取方法综述

    Institute of Scientific and Technical Information of China (English)

    高慧琴; 刘凌

    2011-01-01

    DNA提取是PCR-DGGE技术中首要而关键的一个步骤,不同的方法提取的DNA 产量和纯度等方面有差异,会对后续步骤产生很大影响.综述了目前广泛使用的DNA提取方法,以期为研究者提供参考.%DNA extraction is the primary and key step in PCR-DGGE, and the DNA extracted by different methods varies in yield and purity,which affects the following steps greatly. Here the widely-used DNA extraction methods are summarized so as to provide preference for researchers.

  10. Deterioration to extinction of wastewater bacteria by non-thermal atmospheric pressure air plasma as assessed by 16S rDNA-DGGE fingerprinting.

    Science.gov (United States)

    El-Sayed, Wael S; Ouf, Salama A; Mohamed, Abdel-Aleam H

    2015-01-01

    The use of cold plasma jets for inactivation of a variety of microorganisms has recently been evaluated via culture-based methods. Accordingly, elucidation of the role of cold plasma in decontamination would be inaccurate because most microbial populations within a system remain unexplored owing to the high amount of yet uncultured bacteria. The impact of cold atmospheric plasma on the bacterial community structure of wastewater from two different industries was investigated by metagenomic-based polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) utilizing 16S rRNA genes. Three doses of atmospheric pressure dielectric barrier discharge plasma were applied to wastewater samples on different time scales. DGGE revealed that the bacterial community gradually changed and overall abundance decreased to extinction upon plasma treatment. The bacterial community in food processing wastewater contained 11 key operational taxonomic units that remained almost completely unchanged when exposed to plasma irradiation at 75.5 mA for 30 or 60 s. However, when exposure time was extended to 90 s, only Escherichia coli, Coliforms, Aeromonas sp., Vibrio sp., and Pseudomonas putida survived. Only E. coli, Aeromonas sp., Vibrio sp., and P. putida survived treatment at 81.94 mA for 90 s. Conversely, all bacterial groups were completely eliminated by treatment at 85.34 mA for either 60 or 90 s. Dominant bacterial groups in leather processing wastewater also changed greatly upon exposure to plasma at 75.5 mA for 30 or 60 s, with Enterobacter aerogenes, Klebsiella sp., Pseudomonas stutzeri, and Acidithiobacillus ferrooxidans being sensitive to and eliminated from the community. At 90 s of exposure, all groups were affected except for Pseudomonas sp. and Citrobacter freundii. The same trend was observed for treatment at 81.94 mA. The variability in bacterial community response to different plasma treatment protocols revealed that plasma had a selective impact on bacterial

  11. A Comparison Between Denaturing Gradient Gel Electrophoresis and Denaturing High Performance Liquid Chromatography in Detecting Mutations in Genes Associated with Hereditary Non-Polyposis Colorectal Cancer (HNPCC and the Identification of 9 New Mutations Previously Unidentified by DGGE

    Directory of Open Access Journals (Sweden)

    Meldrum Cliff J

    2003-12-01

    Full Text Available Abstract Denaturing high performance liquid chromatography is a relatively new method by which heteroduplex structures formed during the PCR amplification of heterozygote samples can be rapidly identified. The use of this technology for mutation detection in hereditary non-polyposis colorectal cancer (HNPCC has the potential to appreciably shorten the time it takes to analyze genes associated with this disorder. Prior to acceptance of this method for screening genes associated with HNPCC, assessment of the reliability of this method should be performed. In this report we have compared mutation and polymorphism detection by denaturing gradient gel electrophoresis (DGGE with denaturing high performance liquid chromatography (DHPLC in a set of 130 families. All mutations/polymorphisms representing base substitutions, deletions, insertions and a 23 base pair inversion were detected by DHPLC whereas DGGE failed to identify four single base substitutions and a single base pair deletion. In addition, we show that DHPLC has been used for the identification of 5 different mutations in exon 7 of hMSH2 that could not be detected by DGGE. From this study we conclude that DHPLC is a more effective and rapid alternative to the detection of mutations in hMSH2 and hMLH1 with the same or better accuracy than DGGE. Furthermore, this technique offers opportunities for automation, which have not been realised for the majority of other methods of gene analysis.

  12. Design and application of specific 16S rDNA-targeted primers for assessing endophytic diversity in Dendrobium officinale using nested PCR-DGGE.

    Science.gov (United States)

    Yu, Jie; Zhou, Xiao-Feng; Yang, Sui-Juan; Liu, Wen-Hong; Hu, Xiu-Fang

    2013-11-01

    Novel specific 16S rDNA-targeted primers were successfully designed and applied to the characterization of endophytic diversity in Dendrobium officinale. Using the popular universal bacterial primers 27f/1492r, the fragments of chloroplast and mitochondrion 16S/18S rDNA were amplified from D. officinale. They shared high nucleotide identity with the chloroplast 16S rDNAs (99-100 %) and with the mitochondrion 18S rDNAs (93-100 %) from various plants, respectively, and both shared 73-86 % identities with the bacterial 16S rDNA sequences in GenBank. The current bacterial universal primers, including 27f/1492r, match well with the chloroplast and mitochondrion 16S/18S rDNAs, which accordingly renders these primers not useful for endophytic diversity analysis. Novel 16S rDNA-targeted primers fM1 (5'-CCGCGTGNRBGAHGAAGGYYYT-3') and rC5 (5'-TAATCCTGTTTGCTCC CCAC-3') were designed, which show good specificity compared to the 16S/18S rDNAs of D. officinale, and perfect universality within bacteria except for Cyanobacteria. The primers fM1/rC5, together with 515f-GC/rC5, which overlaps the whole V4 region of 16S rDNA, were subjected to nested polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) to analyze the diversity of endophytic bacteria in D. officinale from three different sources in China. The results showed diversities in roots and stems of the plants from all three locations. Altogether, 29 bands were identified as bacteria, with the dominant group being Proteobacteria and the dominant genus being Burkholderia, some of which commonly has the function of nitrogen fixation and thus may play potentially important roles in D. officinale. Therefore, the nested PCR-DGGE method based on the novel primers provides a good alternative for investigating the communities and roles of endophytes in D. officinale.

  13. 16S rRNA-based PCR-DGGE analysis of actinomycete communities in fields with continuous cotton cropping in Xinjiang, China.

    Science.gov (United States)

    Zhang, Wei; Long, XuanQi; Huo, XiangDong; Chen, YiFeng; Lou, Kai

    2013-08-01

    The purpose of this study was to examine the variations in the microbial community structure of soil actinomycetes in fields with continuous cropping of cotton in Xinjiang Autonomous Region, China. Soil samples were collected from four depths in fields with 7-year continuous cotton cropping. The community structure of soil actinomycetes was examined using the 16S rRNA-based polymerase chain reaction-density gradient gel electrophoresis (PCR-DGGE) techniques. The microbial diversity indices of the soil samples from different depths generally decreased along with the period of continuous cotton cropping. When the period of continuous cropping of cotton reached 5 years, the diversity indices rose again and gradually stabilized at a level slightly lower than that of soils with original ecology (i.e., 0-year cotton cropping). Cluster analysis showed that at the 1-20-cm depth, the actinomycete community structure of the soil subjected to 1-year cotton cropping was similar to that of soil subjected to 0-year cotton cropping, whereas that of soils after 3-year continuous cotton cropping showed high similarity. At the 21-40-cm depth, the actinomycete community structure showed various changes but generally recovered to its original pattern after repeated fluctuations. Principal component analysis showed that at the 1-30-cm depth, the actinomycete community structure varied similarly regardless of the period of continuous cotton cropping. In contrast, there were no clear actinomycete community structure variation trends at the 31-40-cm soil depth. Homology comparison of sequences recovered from the DGGE bands showed that the obtained sequences shared similarities >88 %. Alignment with the known homologous sequences indicated a lack of microorganisms related to soil-borne cotton diseases. Continuous cotton cropping exerted significant influences on the community structure of soil actinomycetes in Xinjiang Autonomous Region, which were largely determined by the soil depth and

  14. Monitoring of bioaerosol inhalation risks in different environments using a six-stage Andersen sampler and the PCR-DGGE method.

    Science.gov (United States)

    Xu, Zhenqiang; Yao, Maosheng

    2013-05-01

    Increasing evidences show that inhalation of indoor bioaerosols has caused numerous adverse health effects and diseases. However, the bioaerosol size distribution, composition, and concentration level, representing different inhalation risks, could vary with different living environments. The six-stage Andersen sampler is designed to simulate the sampling of different human lung regions. Here, the sampler was used in investigating the bioaerosol exposure in six different environments (student dorm, hospital, laboratory, hotel room, dining hall, and outdoor environment) in Beijing. During the sampling, the Andersen sampler was operated for 30 min for each sample, and three independent experiments were performed for each of the environments. The air samples collected onto each of the six stages of the sampler were incubated on agar plates directly at 26 °C, and the colony forming units (CFU) were manually counted and statistically corrected. In addition, the developed CFUs were washed off the agar plates and subjected to polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) for diversity analysis. Results revealed that for most environments investigated, the culturable bacterial aerosol concentrations were higher than those of culturable fungal aerosols. The culturable bacterial and fungal aerosol fractions, concentration, size distribution, and diversity were shown to vary significantly with the sampling environments. PCR-DGGE analysis indicated that different environments had different culturable bacterial aerosol compositions as revealed by distinct gel band patterns. For most environments tested, larger (>3 μm) culturable bacterial aerosols with a skewed size distribution were shown to prevail, accounting for more than 60 %, while for culturable fungal aerosols with a normal size distribution, those 2.1-4.7 μm dominated, accounting for 20-40 %. Alternaria, Cladosporium, Chaetomium, and Aspergillus were found abundant in most

  15. Determination of fruit origin by using 26S rDNA fingerprinting of yeast communities by PCR-DGGE: preliminary application to Physalis fruits from Egypt.

    Science.gov (United States)

    El Sheikha, Aly Farag; Condur, Ana; Métayer, Isabelle; Nguyen, Doan Duy Le; Loiseau, Gérard; Montet, Didier

    2009-10-01

    The determination of geographical origin is a demand of the traceability system of import-export food products. One hypothesis for tracing the source of a product is by global analysis of the microbial communities of the food and statistical linkage of this analysis to the geographical origin of the food. For this purpose, a molecular technique employing 26S rDNA profiles generated by PCR-DGGE was used to detect the variation in yeast community structures of three species of Physalis fruit (Physalis ixocarpa Brat, Physalis pubescens L, Physalis pruinosa L) from four Egyptian regions (Qalyoubia, Minufiya, Beheira and Alexandria Governments). When the 26S rDNA profiles were analysed by multivariate analysis, distinct microbial communities were detected. The band profiles of Physalis yeasts from different Governments were specific for each location and could be used as a bar code to discriminate the origin of the fruits. This method is a new traceability tool which provides fruit products with a unique biological bar code and makes it possible to trace back the fruits to their original location.

  16. Soil clone library analyses to evaluate specificity and selectivity of PCR primers targeting fungal 18S rDNA for denaturing-gradient gel electrophoresis (DGGE).

    Science.gov (United States)

    Takada Hoshino, Yuko; Morimoto, Sho

    2010-01-01

    We evaluated the fungal specificity and detection bias of four fungal 18S rRNA gene (18S rDNA) primer sets for denaturing-gradient gel electrophoresis (DGGE). We constructed and compared clone libraries amplified from upland and paddy field soils with each primer set (1, NS1/GCFung; 2, FF390/FR1-GC; 3, NS1/FR1-GC; and 4, NS1/EF3 for the first PCR and NS1/FR1-GC for the second PCR). Primer set 4 (for nested PCR) showed the highest specificity for fungi but biased specific sequences. Sets 1, 2, and 3 (for single PCR) amplified non-fungal eukaryotic sequences (from 7 to 16% for upland soil and from 20 to 31% for paddy field soil) and produced libraries with similar distributions of fungal 18S rDNA sequences at both the phylum and the class level. Set 2 tended to amplify more diverse fungal sequences, maintaining higher specificity for fungi. In addition, clone analyses revealed differences among primer sets in the frequency of chimeras. In upland field soil, the libraries amplified with primer sets 3 and 4, which targeted long fragments, contained many chimeric 18S rDNA sequences (18% and 48%, respectively), while the libraries obtained with sets 1 and 2, which targeted short fragments, contained fewer chimeras (5% and 10%, respectively).

  17. Isolation and identification of mycorrhizal fungi from Rhododendron hippophaeoides and application of DGGE%灰背杜鹃菌根真菌的分离与鉴定及DGGE的应用

    Institute of Scientific and Technical Information of China (English)

    刘振华; 李潞滨; 童方平; 姚娜

    2012-01-01

    应用传统的培养方法分离菌根真菌,应用ITS rDNA分子生物学手段,进行了菌株的分类鉴定,并结合DGGE(变性梯度凝胶电泳)技术对菌根真菌进行检测.传统培养得到了2种与杜鹃花菌根真菌亲缘关系十分密切的真菌,分别为Phialocephala fortinii和Epacris pulchella root associated fungus.DGGE(变性梯度凝胶电泳)技术检测到1种菌根真菌为Rhizoscyphus ericae.

  18. Isolation,Identification of Fermentation Microorganism in Capsicum chinense Based on PCR-DGGE%利用PCR-DGGE技术筛选分离海南黄帝椒产品微生物

    Institute of Scientific and Technical Information of China (English)

    李汉文; 诸葛斌; 方慧英; 孙进; 龚星慧; 诸葛健

    2012-01-01

    黄帝椒是海南特产高辣度辣椒。该研究以黄帝椒产品为原料,采用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)技术分析了其微生物种群关系,并结合传统平板筛选法进行菌种分离及鉴定,获得了海南特辣黄帝椒产品优势微生物。研究结果显示,海南黄帝椒产品平板筛选分离到了Pseudomonas stutzeri,Lactobacillus plantarum,Lactobacillus brevis等可培养的菌株;DGGE图谱中检测到了6个条带,其中,乳酸菌占总菌数的65%,处于最优势地位,假单胞菌占总菌数的16%,处于次要地位。该研究也首次提及了不同的微生物对黄帝椒产品的颜色、脆性的影响。%Capsicum chinense is a high pungency capsicum fruit specially produced in Hainan Province.A molecular biology method based on polymerase chain reaction(PCR) and denaturing gradient gel electrophoresis(DGGE) was developed to investigate bacterial community of Capsicum chinense,and the traditional isolation method was combined to acquire dominant microorganisms of Capsicum chinense.The results showed that Pseudomonas stutzeri,Lactobacillus plantarum,Lactobacillus brevis,which can be cultured,were screened in Capsicum chinense by traditional isolation method.The six bands'16S rDNA gene sequences were detected in Capsicum chinense by PCR-DGGE,among which Lactobacillus sp.was in a dominant position which is 65% of the total microorganisms.And Pseudomonas stutzeri is in a secondary position which is 16% of the total microorganisms.The browning and the softened coursed by microorganism is reported in Capsicum chinense for the first time.

  19. The Preliminary Analysis of Microflora in Dental Plaque of Twin Children by PCR-DGGE%PCR-DGGE初步分析双胞胎儿童牙菌斑细菌群落组成

    Institute of Scientific and Technical Information of China (English)

    陆剑; 相艳; 李宇红; 杜民权

    2012-01-01

    目的:应用PCR-DGGE技术对双胞胎儿童牙菌斑细菌群落组成进行初步分析.方法:牙菌斑样本取自6对双胞胎儿童,年龄3.5~5.5岁,共17份.分别提取细菌总DNA,PCR扩增16S rDNA V3可变区,产物经DGGE指纹图谱分析其组成.结果:DGGE图谱显示,无龋和患龋双胞胎儿童牙菌斑菌属分布存在差异.结论:PCR-DGGE技术可较直观、灵敏地反应牙菌斑菌属的组成情况.%Objective: To detect bacterial community in dental plaque of twin children by PCR-DGGE. Methods: A total of 17 samples were collected from 6 twins. PCR - based denaturing gradient gel electrophoresis surveys mi-crobial diversity by displaying PCR-generated 16S rDNA V3 fragment that migrate at different distances, reflecting the differences sequence of the fragment. Result: DGGE fingerprint patterns of dental plaque samples showed variation among them. Conclusion: PCR-DGGE method is a sensitive and effective approach to resolve the microflora structure of dental plaque.

  20. Effect of postharvest UV-C treatment on the bacterial diversity of Ataulfo mangoes by PCR-DGGE, survival of E. coli and antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Rocio eFernández-Suárez

    2013-06-01

    Full Text Available Since Mexico is the second largest exporter of mangoes, its safety assurance is essential. Research in microbial ecology and knowledge of complex interactions among microbes must be better understood to achieve maximal control of pathogens. Therefore, we investigated the effect of UV-C treatments on bacterial diversity of the Ataulfo mangoes surface using PCR-DGGE analysis of variable region V3 of 16S rRNA genes, and the survival of E. coli, by plate counting. The UV-C irradiation reduced the microbial load on the surface of mangoes immediately after treatment and the structure of bacterial communities was modified during storage. We identified the key members of the bacterial communities on the surface of fruits, predominating Enterobacter genus. Genera as Lactococcus and Pantoea were only detected on the surface of non-treated (control mangoes. This could indicate that these genera were affected by the UV-C treatment. On the other hand, the treatment did not have a significant effect on survival of E. coli. However, genera that have been recognized as antagonists against foodborne pathogens, were identified in the bands patterns. Also, phenolic compounds were determined by HPLC and antimicrobial activity was assayed according to the agar diffusion method. The main phenolic compounds were chlorogenic, gallic and caffeic acids. Mango peel methanol extracts (UV-C treated and control mangoes showed antimicrobial activity against strains previously isolated from mango, detecting significant differences (P<0.05 among treated and control mangoes after 4 and 12 days of storage. Ps. fluorescens and Ps. stutszeri were the most sensitive.

  1. Effect of postharvest UV-C treatment on the bacterial diversity of Ataulfo mangoes by PCR-DGGE, survival of E. coli and antimicrobial activity.

    Science.gov (United States)

    Fernández-Suárez, Rocío; Ramírez-Villatoro, Guadalupe; Díaz-Ruiz, Gloria; Eslava, Carlos; Calderón, Montserrat; Navarro-Ocaña, Arturo; Trejo-Márquez, Andrea; Wacher, Carmen

    2013-01-01

    Since Mexico is the second largest exporter of mangoes, its safety assurance is essential. Research in microbial ecology and knowledge of complex interactions among microbes must be better understood to achieve maximal control of pathogens. Therefore, we investigated the effect of UV-C treatments on bacterial diversity of the Ataulfo mangoes surface using PCR-DGGE analysis of variable region V3 of 16S rRNA genes, and the survival of E. coli, by plate counting. The UV-C irradiation reduced the microbial load on the surface of mangoes immediately after treatment and the structure of bacterial communities was modified during storage. We identified the key members of the bacterial communities on the surface of fruits, predominating Enterobacter genus. Genera as Lactococcus and Pantoea were only detected on the surface of non-treated (control) mangoes. This could indicate that these genera were affected by the UV-C treatment. On the other hand, the treatment did not have a significant effect on survival of E. coli. However, genera that have been recognized as antagonists against foodborne pathogens were identified in the bands patterns. Also, phenolic compounds were determined by HPLC and antimicrobial activity was assayed according to the agar diffusion method. The main phenolic compounds were chlorogenic, gallic, and caffeic acids. Mango peel methanol extracts (UV-C treated and control mangoes) showed antimicrobial activity against strains previously isolated from mango, detecting significant differences (P mangoes after 4 and 12 days of storage. Ps. fluorescens and Ps. stutszeri were the most sensitive.

  2. 香蕉植株内生细菌群落的PCR—DGGE分析%Analysis of entophytic bacteria community structure in banana by PCR- DGGE technique

    Institute of Scientific and Technical Information of China (English)

    刘菲菲; 李赤; 刘勇勤; 于莉

    2012-01-01

    以健康香蕉植株和感染香蕉枯萎病菌Fusarium oxysporum f.sp.cubense(FOC)后的香蕉植株的根茎叶组织为材料,提取样品中的总DNA,扩增细菌的16SrDNA的V-3可变区,对扩增产物进行DGGE电泳分析,并对其中18条优势条带进行切胶回收、克隆测序和系统发育分析。结果表明,香蕉健株与病株各组织中所含内生细菌的种群丰富度为根部〉假茎〉if片:感病植株组织内生细菌种类比健康植株丰富;BLAST结果为大部分克隆序列与已知细菌16SrDNA基因序列的同源性较高(94%~100%),分别归属于蓝细菌门(Cyanobacteria)、绿弯菌门(Chloroflexi)、放线菌门(Actinobacteria)、变形杆菌门(Proteobacterium)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和绿菌门(Chlorobi)7大类群;其中一个序列同源性较低(91%),可能代表新的分类单元。%The total genomic DNA was extracted from various tissues of both the healthy bananas and the ones which were infected with Fusarium oxysporum f. sp. cubense (FOC). Then the 16Sr DNA V3 frag- ment polymerase chain reaction products amplified from the total genomic DNA were analyzed by denatur- ing gradient gel eleetrophoresis (DGGE). The results of sequence analysis of the 18 DGGE dominant bands showed that the population abundance of endophytic bacteria contained in the healthy banana plants and the infected plants was different. The most abundant population was found in roots , the middle in the bulb tissue and the least in leaves; The abundance of endophytic bacteria increased after infection with FOC; And most of the sequences were phyl0genetically close to Cyanobacteria, Chloroflexi, Actinobacte- ria, Proteobacterium, Bacteroidetes, Firmicutes and Chlorobi ; But the homology for one of the sequences was only 91%. It may represent a new taxon.

  3. Influence of symbiotics on the bacterial community in the cecal contents of broilers analyzed by PCR-DGGE%PCR-DGGE技术分析合生素对肉仔鸡盲肠菌群结构的影响

    Institute of Scientific and Technical Information of China (English)

    杨会玲; 柳永; 许少春; 李艳丽; 许尧兴

    2012-01-01

    试验研究合生素对肉仔鸡盲肠微生物区系的影响.选择1日龄肉仔鸡450只,随机分成5个处理,分别饲喂基础日粮、基础日粮+抗生素、基础日粮+益生素、基础日粮+益生元、基础日粮+合生素,每个处理3个重复,每个重复30只鸡.在21,42日龄每个重复选择2只鸡,无菌采集盲肠内容物,提取细菌基因组总DNA,PCR扩增16s rDNA V3区,扩增产物经变性梯度凝胶电泳(DGGE)后分析细菌群落结构的变化.结果表明,在21,42日龄,日粮添加合生素处理组试验鸡盲肠DGGE条带数均高于其他处理组,合生素组试验鸡盲肠内容物菌群多样性高于其他试验组.序列分析发现肉仔鸡盲肠中特异条带主要来源于不可培养的拟杆菌属、普雷沃氏菌属、梭菌目细菌和其他大量种属关系未知的细菌.%The influence of synbiotics on the predominant bacteria community in the cecal content of broilers was e-yaluated. Four hundred and fifty one-year-old broilers were randomly divided into five treatments of basic diets and basic diets supplemented with antibiotics, probiotics, prebioticts, synbioticts, respectively. On day 21 and 42, two chickens of each replicate were randomly selected and killed, the cecal contents were sterilely collected, and total cellular DNA from the cecal digesta were extracted and purified for PCR-DGGE, then diversity of microbiota was analyzed after DGGE. The results showed the chickens fed with synbiotics showed a higher bacterial diversity and more DGGE bands compared with other treatments on day 21 and 42. The specificity bands of cecal were from uncultured Bacteroid-cdes, uncultured Prevotellaceae, uncultured Clostridiaks and plenty of uncultured bacterial without classification.

  4. Study on sediment microbial community structure in Litopenaeus vannamei ponds covered with a bottom plastic sheet using phospholipid fatty acid (PLFA) analysis%凡纳滨对虾覆膜养殖池塘沉积物微生物群落的磷脂脂肪酸谱图分析

    Institute of Scientific and Technical Information of China (English)

    翟海佳; 郑忠明; 金中文; 陆开宏; 孙芳; 汪洋; 李越蜀

    2011-01-01

    In order to better understand the important role of sediment microorganisms in material cycle and energy flow of aquaculture pond system, three shrimp (Litopenaeus vannamei) ponds covered with plastic sheet in the bottom in Hengshan, Ningbo were chosen and phospholipid fatty acid(PLFA) analysis methods were used to investigate the sediment microbial community structure and its relationship with physical-chemical factors during a three-month period (from June to September, 2010). The results showed that the sediment PLFAs were mainly contributed by the saturated fatty acid, branched fatty acid and monounsaturated fatty acid; the amount of polyunsaturated fatty acid and cyclopropane fatty acid was relatively smaller. The total microbial biomass, bacterial biomass and fungi biomass increased significantly with culture time. The principal component analysis (PCA) of the characteristic PLFAs in different periods showed the total of PCI and PC2 explained the composition of sediment microbial community structure of 81.4%. Although the majority of microorganisms in the sediment were bacteria, bacteria/fungi ratio decreased significantly with culture time due to the better adaptation of fungi to the sediment habitat. The ratios of G+/G- bacteria in the later culture period were smaller compared to the mid-period, but did not change obviously from later period to final-period. Redundancy analysis ( RDA) showed that the total microbial biomass, bacterial biomass and fungi biomass were significantly correlated with the total nitrogen and G + bacterium biomass, G - bacterium biomass were significantly correlated with the NO2- -N, NO3- -N. All of them were negatively correlated with the secchi depth (SD). The experimental results indicated that throughout the whole culture process, environmental factors of this new model ponds showed good consistency and stability. Simultaneously, the diversity of the sediment microbial community and the coordination between the structure

  5. 放牧与围栏内蒙古针茅草原土壤微生物生物量碳、氮变化及微生物群落结构PLFA分析%Analysis of Microbial Biomass C, N and Soil Microbial Community Structure of Stipa Steppes Using PLFA at Grazing and Fenced in Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    赵帅; 张静妮; 赖欣; 杨殿林; 赵建宁; 李刚; 邹雨坤

    2011-01-01

    Soil microbial biomass and community structure were analyzed by using chloroform-fumigation extraction and phospholipid fatty acid( PLFA ) methods, based on 3 different Stipe types(Stipa baicalensis meadow steppe, Stipa grandis typical steppe, and Stipa krylovii typical steppe) in Hulunbeier in Inner Mongolia. The results showed that there were significant differences in soil microbial biomass and community structure at grazing and fenced steppes inside and outside fence. Soil microbial biomass carbon, nitrogen content ranged from 166.6 mg·kg-1 to 703.5 mg·kg-1, 30.34 mg·kg-1 to 92.15 mg·kg-1, respectively. The analysis of Chloroform-fumigation extraction showed that the microbial biomass at Stipa baicalensis meadow steppe was largest, followed by Stipagrandis typical steppe, and the lowest was at Stipa krylovii typical steppe. The microbial biomass at the fenced plots in Stipa baicalensis meadow steppe and Stipa grandis typical steppe was significantly lower than that at the grazing plots, and there was no difference in Stipa krylovii typical steppe. The results of PLFAs displayed that Stipa communities in Inner Mongolia showed abundant species and quantity in soil microbial communities. Total 28 PLFAs biomarkers were detected in the soil samples, with saturated fatty acids and branched fatty acids accounting for 2/3, Stipa baicalensis meadow steppe had the highest content of fatty acid, being 27.3 nmol·g-1. The bacteria PLFAs and total PLFAs in the fenced plots were much higher than those at the grazing plots. The changes of fungi PLFAs varied with different grassland types. Grazing decreased significantly the ratio of gram-positive bacteria PLFAs/gram-negative bacterium PLFAs(GP PLFAs/GN PLFAs ) and remarkably increased the ratio of bacterial PLFAs/fnngi PLFAs except at Stipa krylovii typical steppe. Principal component analysis(PCA) indicated that soil microbial community structure was influenced by different regimes of grassland utilization, grazing

  6. Bulk soil and rhizosphere bacterial community PCR-DGGE profiles and beta-galactosidase activity as indicators of biological quality in soils contaminated by heavy metals and cultivated with Silene vulgaris (Moench) Garcke.

    Science.gov (United States)

    Martínez-Iñigo, M J; Pérez-Sanz, A; Ortiz, I; Alonso, J; Alarcón, R; García, P; Lobo, M C

    2009-06-01

    The biological quality of two heavy metal contaminated soils (soil C: Typic Calcixerept, pH 8.3 and soil H: Typic Haploxeraf, pH 7.3) was investigated after growing the metal-tolerant plant Silene vulgaris (Moench) Garcke for two vegetative periods. The activity of the enzyme beta-galactosidase, which is sensitive to the presence of contaminants in soil, and the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiles of 16S rRNA gene fragments of culturable bacteria from bulk soil and rhizosphere were determined. The microbial enzymatic activity was higher in planted soils than in bare soils at the contamination level of 600 mg of total heavy metals kg(-1) soil. After growing S. vulgaris, beta-galactosidase activity was almost recovered in the calcareous soil. In this soil new bands appeared in the PCR-DGGE profiles of the rhizosphere bacterial community as a response to the exposure to heavy metals.

  7. PCR-DGGE技术对传统发酵酱油的菌群分析%Analysis of Microbial Colonies in Traditional Fermented Soy Sauce by PCR-DGGE Technology

    Institute of Scientific and Technical Information of China (English)

    徐次刚; 周其洋; 赵丽云

    2014-01-01

    γ-aminobutyric acid (GABA)is an important non-protein amino acid .The studies show that GABA can generate in soy sauce fermentation process.In this study,we analyze microbial colonies in traditional fermented soy sauce by PCR-DGGE.The bacterial DGGE profiles of normal soy sauce and GABA elevated soy sauce have great differences,elevated GABA may arise from those bacteria.%γ-氨基丁酸(GABA)是一种重要的非蛋白质氨基酸。有研究表明,在酱油发酵过程中能产生GA-BA。研究利用PCR-DGGE技术分析了正常酱油和GABA升高酱油之间的菌群差异,发现两组样品之间微生物分布存在较大差异,升高的GABA可能来自于这些有差别的微生物。

  8. A preliminary application of PCR-DGGE technology to research the changes of oral microbial floras in chil-dr en with hand foot and mouth disease%PCR-DGGE 技术应用于手足口病儿童口腔微生物菌群变化的初步研究

    Institute of Scientific and Technical Information of China (English)

    施春梅; 周嫣; 方邦骞; 欧晓丽; 谢庆玲; 钟秀芬

    2015-01-01

    Objective To apply PCR-DGGE technology analysing changes of oral microbial floras in children with hand foot and mouth disease( HFMD) .Methods According to the random number table method,3 children with HFMD were randomly chosen and their saliva samples were collected;at the same time, saliva samples were collected from one normal child,and from one child with herpetic ginggivostomatitis(HGS).Samples′total DNA extraction of the microbial community were performed;taking it as template for amplification of 16 s rRNA V3 variable area, the structure of product by the DGGE fingerprint, and using UVIBAND/MAP software for comparing similarity index of the community fingerprint;the edge banding on swimming belt of DGGE fingerprint were excised from the gel for se-quencing, gene sequence analysis was performed, then the sample advantage bacterium group was obtained.Results The advantage bacterial colonies of HFMD group:Capnocytophaga, Selenomonas, Prevotella, TM7_genera_incertae_sedis, Streptococcus, Neisseria, Porphyromonas, Campylobacter, Campylobacter, Granulicatell-a, Leptotrichia, Veil-lonella, Bacteroides-like sp, Actinomyces, Fusobacterium.The advantage bacterial colonies of normal group: Veil-lonella, Capnocytophaga, Prevotella,Gemella , Porphyromonas, Ruminococcaceae, Lachnospiraceae, Selenomonas, Clostridium, Haemophilus.The advantage bacterial colonies of HGS group: Lactococcus,Prevotella.Conclusion The flora structure of HFMD group was more complex, and there was obvious difference in the flora structure between HFMD group and HGS group.%目的:应用PCR-DGGE技术对手足口病( HFMD)、疱疹性口腔炎( HGS)及正常儿童口腔微生物菌群变化进行初步分析,以期了解三者是否存在差异。方法按随机数字表法选择3例手足口病唾液样本,1例幼儿园正常儿童唾液以及1例疱疹性口腔炎患儿唾液。样本进行微生物群落总DNA的抽提;以此为模板扩增16S rRNA V3可变区,产物经DGGE

  9. 16S rRNA基因的PCR-DGGE技术分析逍遥散干预抑郁模型大鼠盲肠菌群的变化%Changes of cecum flora of depressive rats after Xiaoyaosan intervention by PCR-DGGE and 16S rRNA gene library analysis

    Institute of Scientific and Technical Information of China (English)

    沈小丽; 彭国茳; 孙海峰; 田俊生; 秦雪梅

    2015-01-01

    Objective To observe and identify the flora changes in chronic unpredictable mild stress( CUMS) model after intervened by drugs. Methods All SD rats were randomized into four groups:healthy control group, model group,Xiaoyaosan group and fluoxer-tine hydrochloride group. The depressive rat model was coupled by chronic unpredictable mild stress( CUMS) . The rats in healthy con-trol group and model group were given volumetric saline,while the rats in the other groups were given Xiaoyaosan and fluoxetine hydro-chloride at 1 d,respectively. The cecum was taken at 28 d and the genomic DNAs were extracted from all of samples. Denaturing gradi-ent gel electrophoresis(DGGE)fingerprints were constructed by PCR amplification of 16S rRNA V3 variable region. The PCR amplifica-tion product was mixed with competent cells of Escherichia coli DH5α, and formed white colonies were selected and identified. Re-sults The results of body weight and behavior indicated the CUMS model was successfully established, and the index of cecum showed that Xiaoyaosan improved the impact of caecum stimulated by chronic unpredictable mild stress. Combined with DGGE fingerprint of the cecum flora and the measured sequence,the analysis of similarity by the BLAST program showed that four kinds of dominant bacteria were screened, including Lachnospiraceae bacterium, Lactobacillus animali, Burkholderiales bacterium and Lactobacillus reuteri. Com-pared with normal control group,the abundance of Lachnospiraceae bacterium,Lactobacillus animali and Burkholderiales bacterium was enhanced in CUMS group, and the abundance of Lactobacillus reuteri was weakened. After administration of Xiaoyaosan, the abun-dance of Lactobacillus animali was enhanced, the abundance of Lachnospiraceae bacterium showed no significant change and others were not found. Conclusion The cecum flora of depressive rats change markedly by the analysis of DGGE. Xiaoyaosan can regulate the probiotics in cecum flora of depressive rats to

  10. Analysis of the saliva microbial community of chronic periodontitis patients with DGGE%运用DGGE分析慢性牙周炎患者唾液微生物群落结构

    Institute of Scientific and Technical Information of China (English)

    吴明桃; 徐晓; 陈慧; 庞小燕; 赵立平; 唐子圣

    2012-01-01

    Objective To analyze the saliva microflora of chronic periodontitis patients with DCGE. Methods Saliva samples were collected from 33 chronic periodontitis volunteers ( P Group) and 15 non-chronic periodontitis volunteers( NP Group). The total number of samples was 48. All the samples were analyzed with DGGE. Then the DGGE patterns were converted to digital information which was analyzed by three statistical methods "Principal Component Analysis"(PCA),'Cluster Analysis" and "Partial Least Squares"(PLS). Results According to PCA figures,we found that there were not significant differences between P Group and NP Group. Through Cluster Analysis ,we discovered that only a few samples formed clusters. In PLS figures,most of samples in the two groups formed two clusters except a few samples. Conclusions There are not significant differences in the saliva microflora between chronic periodontitis patients and non-chronic periodontitis patients, but there seems to be a tendency of differences.%目的 运用变性梯度凝胶电泳(Denaturing Gradient Gel Electrophoresis,DGGE)技术,分析慢性牙周炎患者唾液中微生物群落结构.方法 采集33名慢性牙周炎志愿者(P组)和15名非慢性牙周炎志愿者(NP组)唾液样本,共计48份.运用DGGE技术分析两组样本微生物群落结构,然后将DGGE凝胶图谱转化成数字信息,进行主成分分析(Principal Component Analysis,PCA)、聚类分析(Cluster Analysis)和偏最小二乘法(Partial Least Squares,PLS)分析.结果 PCA显示P组和NP组没有形成两个明显的聚类群;聚类分析显示两组大部分样本没有形成聚类现象,但少数样本形成聚类现象;PLS显示两组大部分样本形成聚类现象,仅少数样本没有形成聚类现象.结论 慢性牙周炎组和非慢性牙周炎组的唾液微生物群落结构没有显著差异,但存在产生差异的趋势.

  11. 应用巢式PCR-DGGE技术分析稻虱缨小蜂体内Wolbachia的多样性%Diversity of Wolbachia in Anagrus nilaparvatae (Hymenoptera:Mymaridae) analyzed using nested PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    刘淑平; 王新; 徐红星; 汤江武; 郑许松; 杨亚军; 吕仲贤

    2011-01-01

    The objective of this research is to analyze the diversity of Wolbachia in insects by using nested PCR-DGGE. Samples of Anagrus nilaparvatae, one of dominant egg parasitoids of rice planthoppers in Asian rice growth area, were collected from Hangzhou, China and the Philippines. After the total DNA was extracted, the 16S rDNA and wsp gene fragments of Wolbachia were amplified with nested PCR, and then analyzed using DGGE. The results showed that Wolbachia in A. Nilaparvatae were sensitively and exactly detected based on 16S rDNA gene, and the dominant bacteria in A. Nilaparvatae were Acinetobacter sp., Methylophilus sp., Acidovorax sp., Burkholderia sp. And Wolbachia sp. The analysis of wsp gene showed that Wolbachia in A. Nilaparvatae from Hangzhou belongs to group A, sub-group Mors, and that from the Philippines belongs to group A, sub-group Dro. The results suggest that nested PCR-DGGE is an effective molecular tool for detecting the diversity of Wolbachia in Anagrus sp., and the 16S rDNA gene fragment is the optimal biomarker for Wolbachia detection, while the wsp gene is the optimal biomarker for Wolbachia species identification and classification.%以采集自中国杭州和菲律宾的稻虱缨小蜂Anagrus nilaparvatae为研究对象,采用巢式PCR扩增Wolbachia的16S rDNA和wsp基因片段,并用DGGE分析稻虱缨小蜂体内Wolbachia的多样性.基于16S rDNA基因的分析结果准确地检测到稻虱缨小蜂体内细菌主要是Acinetobacter sp.,Methylophilus sp.,Acidovorax sp.,Burkholderia sp.和Wolbachia sp..基于wsp基因的分析结果显示,杭州种群感染的Wolbachia属于A组的Mors亚组,菲律宾种群感染的Wolbachia属于A组的Dro亚组.结果说明,巢式PCR-DGGE是寄生蜂体内Wolbachia检测和多样性分析的有效方法,其中16S rDNA基因是检测Wolbachia存在的较佳分子标记,wsp基因是Wolbachia多样性分析以及种属鉴定和分型的较佳分子标记.

  12. Analysis of Intestinal Bacterial Communities in Apriona germari Adult Based on PCR-DGGE Technology%利用PCR-DGGE技术分析桑天牛成虫肠道细菌菌群

    Institute of Scientific and Technical Information of China (English)

    李会平; 袁秀洁; 苏筱雨

    2012-01-01

    In order to acquire biodiversity information of intestinal microorganisms in Apriona germari adult, PCR-DGGE technology was employed to analyze the composition of microorganism populations and dominant bacteria in intestine of A. Germari adult. After genomic DNA extraction from bacteria in intestine of A. Germari adult, we amplified 16S rDNA V3 variable region by PCR with 27F/1495R and 27F/519r + GC universal primers and obtained an amplified product of around 500 bp, which was further isolated by denaturing gradient gel electrophoresis (DGGE). After dominant band a-nalysis, DNA recovery, cloning and sequencing, 8 bacterial strains were obtained. They belonged to Enterobacter, Acinetobacter, Escherichia, Citrobacter, Klebsiella, Shigella, Pantoea, Serratia respectively, among which the bacterial strain belonged to Klebsiella was the dominant strain, followed by the bacterial strain belonged to Serratia. Blast search with the obtained bacterial 16S rDNA sequences in GenBank database showed that there were 6 bacterial strains showing similarity over 97%, among which 5 bacterial strains were consistent with the classification by traditional methods. These results showed that PCR-DGGE technology based on 16S rDNA can be used to study biodiversity of intestinal microorganisms in A. Germari.%利用PCR-DGGE技术分析桑天牛成虫肠道菌群结构及优势菌群,获取桑天牛肠道微生物的多样性信息.从桑天牛成虫肠道中提取细菌基因组DNA,以细菌16S rDNA基因通用引物27F/1495R和27 F/519r+ GC进行V3可变区PCR扩增,将长约500 bp的扩增产物经变性梯度凝胶电泳(DGGE)分离后,进行优势条带分析、DNA回收、克隆、测序等,初步得到分别属于肠杆菌属(Enterobacter)、不动杆菌属(Acinetobacter)、埃希氏菌属(Escherichia)、志贺菌属(Citrobacter)、克雷伯氏菌属(Klebsiella)、柠檬酸菌属(Shigella)、泛菌属(Pantoea)和沙雷氏菌属(Serratia)的8个细菌菌株,其中优势细菌为克

  13. Analysis of 65 tuberous sclerosis complex (TSC) patients by TSC2 DGGE, TSC1/RSC2 MLPA, and TSC1 long-range PCR sequencing, and report of 28 novel mutations

    DEFF Research Database (Denmark)

    Rendtorff, Nanna D.; Bjerregaard, Bolette; Frödin, Morten

    2005-01-01

    Tuberous sclerosis complex (TSC) is a severe autosomal-dominant disorder characterized by the development of benign tumors (hamartomas) in many organs. It can lead to intellectual handicap, epilepsy, autism, and renal or heart failure. An inactivating mutation in either of two tumor-suppressor ge......Tuberous sclerosis complex (TSC) is a severe autosomal-dominant disorder characterized by the development of benign tumors (hamartomas) in many organs. It can lead to intellectual handicap, epilepsy, autism, and renal or heart failure. An inactivating mutation in either of two tumor...... for detecting mutations in TSC: a denaturing gradient gel electrophoresis (DGGE) analysis for small TSC2 mutations, a multiplex ligation-dependent probe amplification (MLPA) analysis for large deletions and duplications in TS1 or TSC2, and a long-range PCR(sequencing-based analysis for small TSC1 mutations...

  14. Analysis of 65 tuberous sclerosis complex (TSC) patients by TSC2 DGGE, TSC1/RSC2 MLPA, and TSC1 long-range PCR sequencing, and report of 28 novel mutations

    DEFF Research Database (Denmark)

    Rendtorff, Nanna D.; Bjerregaard, Bolette; Frödin, Morten;

    2005-01-01

    Tuberous sclerosis complex (TSC) is a severe autosomal-dominant disorder characterized by the development of benign tumors (hamartomas) in many organs. It can lead to intellectual handicap, epilepsy, autism, and renal or heart failure. An inactivating mutation in either of two tumor-suppressor ge......Tuberous sclerosis complex (TSC) is a severe autosomal-dominant disorder characterized by the development of benign tumors (hamartomas) in many organs. It can lead to intellectual handicap, epilepsy, autism, and renal or heart failure. An inactivating mutation in either of two tumor...... for detecting mutations in TSC: a denaturing gradient gel electrophoresis (DGGE) analysis for small TSC2 mutations, a multiplex ligation-dependent probe amplification (MLPA) analysis for large deletions and duplications in TS1 or TSC2, and a long-range PCR(sequencing-based analysis for small TSC1 mutations...

  15. Diversity Analysis of Intestinal Microlfora from Healthy Cow and Mastitis Cow by PCR-DGGE%PCR-DGGE法分析健康奶牛和乳房炎患牛肠道微生物菌群的多样性

    Institute of Scientific and Technical Information of China (English)

    赵洁; 马晨; 席晓敏; 王慧艳; 丁佳; 张和平

    2014-01-01

    In order to reveal the diversity and differences of cow with infectious mastitis and healthy cow intestinal microlfora, fecal samples of ten healthy cows and ten mastitis cows were collected in Inner Mongolia. Diversity of bacteria, Lactobacillus species and ciliate population was analyzed by denaturing gradient gel electrophoresis (DGGE). Intestinal microlfora of healthy cow and mastitis cow could be drawn with obvious differences by cluster analysis,similarity analysis and PLS-DA analysis. Compared with intestinal microflora of healthy cows, the diversity of Lactobacillus and ciliate of mastitis cows were lower. PCR-DGGE technology analyzed the diversity of intestinal microlfora and provided theoretical basis for treatment of disease by probiotic.%为了探究健康牛和乳房炎患牛肠道微生物多样性及其差异性,本试验采用PCR-DGGE技术对采自内蒙古的10头健康牛及10头患病牛粪便中的细菌、乳杆菌属及纤毛虫进行分析。通过聚类分析、相似性分析及PLS-DA分析可知,健康牛和患乳房炎牛肠道微生物菌群存在明显的差异性,与健康牛相比,乳房炎患牛肠道中乳杆菌和纤毛虫多样性明显较低。PCR-DGGE技术直观全面地分析了肠道微生物菌群的多样性,为后续益生菌治疗疾病试验提供理论依据。

  16. The Optimization of Bacterial Colonies PCR-DGGE Primers inPig Nasal Cavity%猪鼻腔中细菌菌落PCR-DGGE引物条件优化

    Institute of Scientific and Technical Information of China (English)

    陈江

    2015-01-01

    变性梯度凝胶电泳(Denaturing gradient gel electrophoresis, DGGE)技术是最先用于 DNA 突变检测的一种电泳技术。为获得最佳的PCR-DGGE上样模板,本实验分别采用十六烷基三甲基溴化铵(CTAB)法和Power Soil DNA Isolation Kit试剂盒抽提细菌基因组DNA,分别以Primer(338F/518R)/Primer(P2/P3)为16Sr DNA V3扩增引物,采用温度梯度PCR对引物扩增条件进行优化。结果显示:在Tm 56℃,通过CTAB法抽提细菌基因组DNA,采用primer(338F/518R)扩增16Sr DNA V3目的产物特异性最佳。%Denaturing gradient gel electrophoresis (DGGE) technology is the first electrophoresis technique to detect DNA mutations .In order to obtainthe optimalof PCR-DGGE template, cetyltrimethyl ammonium bromide (CTAB) method and the Power Soil DNA Isolation Kitare used to extractbacterialmetagenome. Besides, Primer(338F/518R)and Primer(P2/P3)were respectivelyused for 16Sr DNA V3 amplification, temperature gradient PCRwere optimizedfor primer amplification conditions. Results showed thatextracting bacteriametagenome by CTAB and usingprimer A (338 f / 518 r) , are the best way of 16Sr DNA amplification productin Tm 56℃.

  17. PCR-DGGE Analysis of Dominant Bacteria in Yak Meat during Chilled Storage%冷却牦牛肉贮藏过程中优势菌的PCR-变性梯度凝胶电泳分析

    Institute of Scientific and Technical Information of China (English)

    岑璐伽; 唐善虎; 郝小倩; 李雪; 邓宇

    2012-01-01

    In this study, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to investigate the changes in microbial diversity and dynamic changes of tray-packaged chilled yak meat during storage at 4 ℃. of Total bacterial DNA was directly extracted from meat samples. The touchdown PCR was applied to amplify the V3 region of the 16S rDNA gene before DGGE analysis. By analysis of the dynamic community directly obtained from the DGGE profiles and the DNA sequences of main bands, the predominant spoilage bacteria were found to be Pseudomonas sp., Lactococcus sp., Acinetobacter sp., Brochothrix thermosphacta and Enterobacteriaceae bacterium. Uncultured Citrobacter sp. and Staphylococcus sp. were also identified in this study.%应用聚合酶链式反应.变性梯度凝胶电泳(PCR.DGGE)技术,研究托盘保鲜膜包装的冷却牦牛肉在4℃贮藏过程中的微生物多样性及其动态变化。直接从样品中提取细菌总的DNA,采用降落PCR扩增168rDNA的V3可变区序列,再通过DGGE得到动态变化的指纹图谱,并对主要条带进行测序分析。结果表明:检测到的优势腐败菌为Pseudomonassp.(假单胞菌)、Lactococcus sp.(乳球菌)、Acinetobactersp.(不动杆菌)、Brochothrixthermosphacta(热死环丝菌)、Enterobacteriaceaebacterium(肠杆菌科细菌),此外还检测到UnculturedCitrobactersp.(非培养的柠檬酸杆菌)和Staphylococcussp.(葡萄球菌)。

  18. PCR-DGGE Analysis of Lactic Acid Bacterial Community Structure in Pickled Mustard Tuber%基于PCR-DGGE方法分析榨菜中乳酸菌群落结构

    Institute of Scientific and Technical Information of China (English)

    燕平梅; 乔宏萍; 赵文婧; 单树花; 王琪; 柴政; 陈燕飞

    2016-01-01

    为了深入了解榨菜中的乳酸菌多样性以及影响因素,以市场销售含有辣椒和不含辣椒两种袋装榨菜为研究对象,测定榨菜中的食盐浓度以及亚硝酸盐含量;通过变性梯度凝胶电泳(denaturing gradient gel electrophoresis, DGGE)法分离榨菜总微生物混合16S rDNA基因V7~V8片段,采用Quantity One软件分析乳酸菌物种丰富度、均匀度及物种多样性指数。结果表明:含辣椒的榨菜食盐浓度和亚硝酸盐含量均略低于不含有辣椒的榨菜;含有辣椒和不含辣椒的榨菜两者间物种多样性指数、丰富度和均匀度无显著差异(P>0.05)。通过回收DGGE电泳带,经克隆后测定碱基序列、与GenBank库序列对比鉴定,不含有辣椒的榨菜5条回收聚合酶链式反应(polymerase chain reaction,PCR)-DGGE泳带a、b、c、d、e经鉴定分别与Pediococcus argentinicus CRL 776、Uncultured Lactobacillus sp. isolate DGGE gel band lx12、Uncultured bacterium clone 11.02-12、Uncultured bacterium clone 11.02-9、Uncultured Lactobacillus sp. clone PxSC03相似度为98%、96%、97%、97%、97%。含有辣椒的榨菜4条回收PCR-DGGE泳带1、2、3、4经鉴定分别与Uncultured Lactobacillus sp.、Lactobacillus sakei A156、Lactobacillus sakei YY1、Lactobacillus sakei WJ1相似度为96%、97%、98%、97%。研究结果表明辣椒对榨菜中微生物群落结构无显著影响。%In order to understand the diversity of lactic acid bacteria in pickled mustard tuber and its influencing factors, two commercial bagged pickled mustard tubers (with and without hot pepper) were determined for the contents of salt and nitrite, and the V7-V8 region of total bacterial 16S rDNA sequences was separated by denaturing gradient gel electrophoresis (DGGE). Furthermore, the species richness, evenness and diversity of lactic acid bacteria were analyzed by the Quantity One software. Results indicated that the contents of salt and nitrite

  19. DGGE analysis of bacterial community structure in mandibular third molar pericoronitis%急性下颌智牙冠周炎菌群结构变性梯度凝胶电泳分析

    Institute of Scientific and Technical Information of China (English)

    张昕; 孙正; 谭亚军; 杨秋波

    2011-01-01

    目的 应用变性梯度凝胶电泳技术,分析急性下颌智牙冠周炎菌群结构.方法 采集29例急性下颌智牙冠周炎盲袋内细菌标本,提取细菌总DNA,巢式聚合酶链反应扩增全部细菌16S rDNA基因V2-V3可变区.变性梯度凝胶电泳对PCR扩增产物进行分离.应用BioNumerics软件对DGGE图像资料进行聚类分析,对比不同类别样本中的临床资料、条带数量和条带模式.结果 29例急性下颌智牙冠周炎细菌16S rDNA基因条带数量和条带模式存在不同.通过聚类分析可将临床样本聚为2组,2组间临床资料的差异没有统计学意义;但条带数量和相似系数均不同,差异具有统计学意义.结论 急性下颌智牙冠周炎临床状态基本相同,而菌群结构不同.DGGE技术和聚类分析可用于急性下颌智牙冠周炎细菌菌群结构的研究.%Objective To investigate the bacterial community structure in pericoronitis of the mandibular third molar. Methods Twenty-nine samples were taken from the pockets of pericoronitis of mandibular third molar in 29 patients. All DNA was extracted for a nested amplification of the V2-V3 hypervariable region of 16S ribosomal RNA gene ( 16S rDNA) with GC rich clamp at the 5'-end. PCR-generated DNA fragments of the same length but with different basepair sequences were separated by denaturing gradient gel electrophoresis ( DGGE). DGGE band patterns of 16S rDNA profiles were objectively digitized using BioNumerics software. Results Distinct band number and patterns were observed in all twenty-nine cases. Cluster analysis of DGGE band polymorphism clearly divided pericoronitis cases into two groups according to band patterns. The overall differences in the band number and patterns between cluster A and cluster B were statistically significant Conclusion Pericoronitis of the mandibular third molar presents the same symptoms whereas the structure of the bacterial community in pericoronitis cases are significantly

  20. 奶牛隐性乳房炎病原菌的分离鉴定与DGGE追溯%Isolation and Identification of the Cow Subclinical Mastitis Pathogens and DGGE Retrospective Analysis

    Institute of Scientific and Technical Information of China (English)

    高潮; 刘国庆; 连英琪; 朱明; 余晓峰; 张克春

    2013-01-01

    通过对隐性乳房炎病原菌的分离鉴定和药敏试验,以及对治疗前的奶样进行DGGE追溯性分析,研究乳房炎奶样中微生物区系结构对乳房炎的治疗和复发的影响.结果显示,引起奶牛隐性乳房炎的主要病原菌为大肠杆菌、金黄色葡萄球菌、无乳链球菌、表皮葡萄球菌以及克雷伯菌.通过对大肠杆菌性乳房炎奶样进行DGGE追溯性分析,发现乳房炎奶样中除大肠杆菌外,还有假单胞菌、芽孢杆菌、链球菌、沙雷氏菌等其他的致病菌,并且奶样中微生物区系结构与奶牛乳房炎的治愈时间和乳房炎复发有着紧密的联系,区系结构越复杂,治愈的时间越长,越容易复发,引起后期乳房炎复发的病原菌包含在治疗前的奶样中.%In order to clarify the impacts of microbial community structure in mastitis milk samples upon the treatment and recurrence of mastitis,in this study,we performed isolation,identification and susceptibility test of pathogenic bacteria of recessive mastitis and retrospective analysis of DGGE in milk samples before the treatment of mastitis.The results showed that the major pathogenic bacteria causing recessive mastitis in diary cattle were Escherichia coli,Staphylococcus aureus,Streptococcus agalactiae,Staphylococcus epidermidis and Klebsiella.Based on the retrospective analysis of DGGE in milk samples of E.coli mastitis,it was found that Pseudomonas,Bacillus,Streptococcus,Serratia and other pathogenic bacteria were detected in the milk samples except E.coli.In addition,the microbial community structure in milk samples indicated close relationship with the healing time and recurrence of cow mastitis.The more complicated the community structure,the more time it should cost for the mastitis to heal and the more opportunities there are for mastitis to recur.

  1. Analysis of Microbial Community Structures in Kefir Grains By PCR-DGGE Techniques%PCR-DGGE技术对中华开菲尔微生物菌群的分析

    Institute of Scientific and Technical Information of China (English)

    林晓珊; 阮征; 刘飞; 张毅

    2013-01-01

    The dynamic variation of microbial flora in kefir liquor during its fermentation was studied by PCR-DGGE technique.The analysis result showed that 3 different visible bands in bacteria community and only 1 band in yeast community were obtained in their electrophoresis pattern.Anaylsis of 16SrDNA sequence blast showed that these sequences of all 3 different visible bands had a high homology with the sequence of 16S rDNA of lactic acid bacteria (LAB).They belonged to Leuconostoc mesenteroides,Lactobacillus kefiranofacien and Lactobacillus kefir.The sequence of the band in yeast community had a high homology with the 16S rDNA of yeast Torulaspora delbrueckii.Yeast Torulaspora delbrueckii was,for the first time,found in kefir grains.%为了解中华开菲尔微生物菌群的结构特征,本论文运用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)技术对开菲尔菌株发酵过程中微生物菌群的结构变化进行了实验分析,结果表明:细菌菌群DGGE图谱上出现有三种不同迁移位置的斑带,而酵母菌群DGGE图谱上只有一条斑带;经过DNA序列的对比分析可知:细菌菌群分别为肠膜明串珠菌(Leuconostoc mesenteroides)、马乳样乳杆菌(Lactobacillus kefiranofaciens)和开菲尔乳杆菌(Lactobacillus kefir),它们的序列同源性都达到100%;酵母菌群为德尔布有孢圆酵母(Torulaspora delbrueckii),其序列同源性为99%.本论文首次报道了德尔布有孢圆酵母在开菲尔菌落中的存在.

  2. 圆白鲳消化道菌群PCR-DGGE基因指纹图谱构建%Construction of PCR-DGGE gene fingerprint for the gastrointestinal bacterial community in Ephippus orbis

    Institute of Scientific and Technical Information of China (English)

    周志刚; 石鹏君; 姚斌; 何夙旭

    2008-01-01

    采取免培养的16S rDNA梯度凝胶电泳(DGGE)技术对集约化海水网箱养殖圆白鲳Ephippus orbis(体重17.7±3.0 g)包括胃壁、胃内容物、肠壁及肠内容物在内的消化道菌群结构进行了初步分析.DGGE指纹图谱显示圆白鲳胃内容物、胃壁及肠壁有7条明显条带,肠内容物有6条明显条带,提示圆白鲳消化道可能存在着较丰富细菌群落;针对指纹图谱的聚类分析表明胃内容物及肠内容物细菌组成相似度最高达90.0%,而胃壁与肠壁的相似度相对较差达80%.半定量分析表明圆白鲳消化道菌群相对丰度的变异系数均大于47.4%,暗示圆白鲳消化道趋向于以一种或极少数种细菌占统治地位.

  3. 川纹笛鲷消化道优势菌群PCR-DGGE指纹图谱比较分析%Comparison of the PCR-DGGE fingerprints in the gastrointestinal predominant bacterial community in Lutjanus sebae

    Institute of Scientific and Technical Information of China (English)

    周志刚; 石鹏君; 姚斌; 何夙旭; 苏永全

    2008-01-01

    采用免培养的16S rDNA梯度凝胶电泳技术(DGGE)对集约化海水网箱养殖川纹笛鲷(Lutjanussebae)的消化道胃壁、胃内容物、肠壁、肠内容物优势菌群结构进行了比较分析.研究结果显示,川纹笛鲷消化道存在着丰富多样的细菌群落,对DGGE指纹图谱聚类分析表明菌群组成相似度高于55%,其中胃内容物及胃壁细菌组成相似度最高(90%),这可能与摄食饵料在消化道推移有关;而胃壁与肠壁相似度相对最差,可能反应了由于生理环境不同引起的宿主差异性.通过建立川纹笛鲷消化道16S rDNA-DGGE指纹图谱及比较分析,为澄清川纹笛鲷消化道微生物区系奠定了基础.

  4. Principle of DGGE and Its Application in Animal Gastrointestinal Microbiota System%DGGE技术的原理及其在动物胃肠道微生态系统研究中的应用

    Institute of Scientific and Technical Information of China (English)

    鲍新宇; 杨剑; 高新艳; 周勤飞; 王永才

    2011-01-01

    It is difficult to cultivate all flora in animal gastrointestinal tract by using traditional methods, so it is difficult to identify the difference of animal gastrointestinal microbes in each stage. Denaturing gradient gel electrophoresis (DGGE) can avoid the disadvantages of traditional methods and can confirm the difference in animal gastrointestinal microbiota system and the diversity of flora. The basic principle, advantages and disadvantages of DGGE and its application in animal gastrointestinal microbiota system were mainly summarized in this paper.%利用传统的培养方法很难将动物胃肠道的所有菌群进行培养,因此也很难鉴别各个时期动物胃肠道微生物之间的差异。变性梯度凝胶电泳(DGGE)技术可以避免传统方法的弊端,进而可以进一步确定动物胃肠道微生态系统的差别以及茵群的多样性。主要综述了DGGE技术的原理、优缺点以及在动物胃肠道微生态系统研究中的应用和前景。

  5. Impact of a probiotic, inulin, or their combination on the piglets' microbiota at different intestinal locations.

    Science.gov (United States)

    Sattler, V A; Bayer, K; Schatzmayr, G; Haslberger, A G; Klose, V

    2015-01-01

    Natural feed additives are used to maintain health and to promote performance of pigs without antibiotics. Effects of a probiotic, inulin, and their combination (synbiotic), on the microbial diversity and composition at different intestinal locations were analysed using denaturing gradient gel electrophoresis (DGGE), real-time PCR, and 16S rRNA gene pyrosequencing. Bacterial diversity assessed by DGGE and/or pyrosequencing was increased by inulin in all three gut locations and by the synbiotic in the caecum and colon. In contrast, the probiotic did only affect the microbiota diversity in the ileum. Shifts in the DGGE microbiota profiles of the caecum and colon were detected for the pro- and synbiotic fed animals, whereas inulin profiles were more similar to the ones of the control. 16S rRNA gene pyrosequencing revealed that all three additives could reduce Escherichia species in each gut location, indicating a potential beneficial effect on the gut microbiota. An increase of relative abundance of Clostridiaceae in the large intestine was found in the inulin group and of Enterococcaceae in the ileum of probiotic fed pigs. Furthermore, real-time PCR results showed that the probiotic and synbiotic increased bifidobacterial numbers in the ileum, which was supported by sequencing results. The probiotic and inulin, to different extents, changed the diversity, relative abundance of phylotypes, and community profiles of the porcine microbiota. However, alterations of the bacterial community were not uniformly between gut locations, demonstrating that functionality of feed additives is site specific. Therefore, gut sampling from various locations is crucial when investigations aim to identify the composition of a healthy gut microbiota after its manipulation through feed additives.

  6. DGGE Analysis of Fungi Community Structure,Isolation and Identification of Yeasts from Salted Raphanus sativus%盐渍白萝卜的真菌菌群结构DGGE分析及酵母菌分离鉴定

    Institute of Scientific and Technical Information of China (English)

    尹礼国; 马伟玲; 李文芳; 魏劲松; 张其圣; 罗青春; 陈功; 吴正云; 张文学

    2015-01-01

    The fungi communities of different salted Raphanus sativus are analyzed by denatured gradient gel electrophoresis (DGGE ).The dominant fungi groups of salted Raphanus sativus are Candida lactis-condensi,Candida versatilis,Candida sp.,Pichi sp.,the closest species are Candida lactis-condensi,Candida versatilis,Pichia membranifaciens,Debaryomyces hansenii.17 yeasts are isolated from salted Raphanus sativus by cultivation methods,and are identified by molecular biology methods,the strains are Pichi sp.,Pichia membranefaciens,and Debaryomyces hansenii.Candida lactis-condensi and Candida versatilis are not isolated with the cultivation methods.DGGE is a suitable tool for the analysis of fungi communities of salted Raphanus sativus,as it is more rapid and comprehensive than cultivation methods detection of species.%采用变性梯度凝胶电泳技术(denatured gradient gel electrophoresis,DGGE)对不同盐渍白萝卜样品的真菌菌群结构分析表明,犆犪狀犱犻犱犪犾犪犮狋犻狊-犮狅狀犱犲狀狊犻、犆犪狀犱犻犱犪狏犲狉狊犪狋犻犾犻狊、膜醭毕赤酵母(犘犻犮犺犻犪犿犲犿犫狉犪狀犻犳犪犮犻犲狀狊)、汉逊德巴氏酵母菌(犇犲犫犪狉狔狅犿狔犮犲狊犺犪狀狊犲狀犻犻)为盐渍萝卜的优势菌。通过传统分离培养技术从样品中分离到17株酵母菌,通过分子生物学鉴定为犘犻犮犺犻犪sp 。、膜醭毕赤酵母(犘犻犮犺犻犪犿犲犿犫狉犪狀犲犳犪犮犻犲狀狊)、德巴利酵母属(犇犲犫犪狉狔狅犿狔犮犲狊sp 。)。传统分离培养技术未分离到犆犪狀犱犻犱犪犾犪犮狋犻狊-犮狅狀犱犲狀狊犻,犆犪狀犱犻犱犪狏犲狉狊犪狋犻犾犻狊。DGGE技术能够快速高效、直观地反映盐渍白萝卜的菌群结构,结果合理。

  7. 利用PCR-DGGE分析海水浴场细菌多样性%Analysis of bacterial community diversity of marine bathing beach water by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    李江宇; 樊景凤; 穆贵强; 李洪波; 韩俊丽; 高小玉

    2013-01-01

    2011年5月,于大连星海浴场采集海水样品,采用PCR-DGGE技术分析其细菌多样性.分析结果表明:近排污口处水样细菌群落多样性较远排污口处高,细菌类群主要由厚壁菌门(53%)、变形菌门(26.7% ~ 29.4%)和拟杆菌门(17.6% ~20%)组成,其中可培养细菌类群序列占总细菌类群序列的64.7%~66.7%,离排污口较远处水样中可培养细菌类群中乳酸杆菌所占总测序序列的比例最高(13.3%),而近排污口处为弓形杆菌(11.8%)和梭菌(11.8%)最高.浴场中拟杆菌和嗜低温弓形菌(Arcobacter cryaerophilus)为优势菌,其中嗜低温弓形菌为致病菌,其他致病性细菌没有被检测到;由于DGGE有一定的基因含量检测限度,所以表明嗜低温弓形菌较其他可能存在于浴场中的致病菌的丰度高.%The bacterial community diversity of Xinghai Bathing Beach was analysed by PCR-DGGE in Dalian in May,2011.The bacterial diversity of water samples nearer from a off-shore sewage outfall was higher than other locations.Three bacteria phyla Firmicutes (53 %)、Proteobacteria (26.7% ~ 29.4%) and Bacteroidetes (17.6% ~ 20%) make up the majority of the predominant bacteria structure,Lactobacillus spp.(13.3%) in the water with a longer distance from the sewage outfall and Arcobacter spp.(11.8%) and Clostridium spp.(11.8%) in the water with a shorter distance from the sewage outfall were the predominant phyla of the cultured bacterial phyla which were 64.7% ~ 66.7% in the total bacterial phyla.Bacteroides sp.of the uncultured bacterial phyla and Arcobacter cryaerophilus of the cultured bacterial phyla were the predominant bacterial population,Arcobacter cryaerophilus of which was detected as a kind of pathogenic bacterium,the other pathogenic bacteria were not detected,which suggested that Arcobacter cryaerophilus may have a great richness than other pathogenic bacterium which possibly survived but not detected in the

  8. PCR-DGGE Analysis of the Microbial Diversity in Naturally Fermented Suan-cai from Northeast China%PCR-DGGE分析东北自然发酵酸菜中的微生物多样性

    Institute of Scientific and Technical Information of China (English)

    乌日娜; 于美玲; 孟令帅; 徐鑫; 岳喜庆; 武俊瑞

    2014-01-01

    为了探明传统的自然发酵酸菜中微生物的多样性和优势菌群,通过聚合酶链式反应-变性梯度凝胶电泳(polymerase chain reaction-denaturing gradient gel electrophoresis,PCR-DGGE)技术分析酸菜发酵过程中微生物群落动态变化.结果表明:东北自然发酵酸菜中的细菌种类比较丰富,真菌在酸菜中存在相对较少.东北自然发酵酸菜在发酵早期的活跃菌为明串珠菌(Leuconostoc sp.),而后是发酵产酸的嗜酸乳杆菌(L.acidophilus)、发酵乳杆菌(L.fermentum)和植物乳杆菌(L.plantarum),最后是由植物乳杆菌完成发酵过程.其中明串菌株为酸菜发酵前期优势细菌,植物乳杆菌为发酵中后期优势细菌,东北自然发酵酸菜发酵过程中主要真菌为汉逊德巴利酵母(Debaryomycs hansenii)、热带假丝酵母(Candida tropicalis)、扩展青霉(Penicillium expansum),真菌数量随发酵时间的增加而减少,且种类也随时间的变化而不断变化.

  9. Investigating the Diversity of Lactic Acid Bacteria in Tibetan Traditional Fermented Dairy Products by PCR-DGGE%PCR-DGGE法分析西藏传统发酵乳制品中乳酸菌的多样性

    Institute of Scientific and Technical Information of China (English)

    蒋厚阳; 陈芝兰; 赵国华; 杨吉霞

    2014-01-01

    目的:运用聚合酶链式反应和变性梯度凝胶电泳(polymerase chain reaction-denatured gradient gel electrophoresis,PCR-DGGE)技术分析西藏传绩发酵乳制品中乳酸菌的生物多样性.方法:从西藏8个牧区采集19份样品,提取样品总DNA,用巢式和降落PCR扩增16S rRNA的V3区段,对扩增产物做变性梯度凝胶电泳,用NTsys 2.10e软件分析条带的相似性,切胶回收条带并测序,鉴定菌种并构建系统进化树、分析优势菌种.结果:19份样品中的乳酸菌菌群组成包括Lactobacillus paracasei、Lactobacillus helveticus、Lactobacillus fermentum、Lactobacillus crispatus、Lactobacillus delbrueckii、Lactobacillus buchneri、Lactococcus raffinolactis、Leuconostoc mesenteroide、Lactobacillus plantarum、Pediococcus pentosaceus、Lactococcus lactis、Streptococcus thermophilus.综合样品和牧区的乳酸菌分布情况,确定Lactobacillus delbrueckii为优势菌种.结论:PCR-DGGE技术能够有效分析西藏地区发酵乳制品中乳酸菌的多样性.

  10. 循环水养殖系统生物滤池细菌群落的PCR-DGGE分析%PCR-DGGE analysis of bacterial communities in bio-filtors of re-circulating mariculture system

    Institute of Scientific and Technical Information of China (English)

    李秋芬; 傅雪军; 张艳; 马绍赛

    2011-01-01

    通过模拟实验对循环水养殖系统中不同初始NH+4-N浓度的生物滤池中生物膜上和水中的细菌数量及群落种类组成进行了研究.对成熟生物膜及水体样品中的异养菌、氨氧化菌、亚硝酸盐氧化菌的培养计数结果表明,随着生物滤池初始氨氮浓度增大,除异养细菌数量逐渐下降外,生物膜上的氨氧化菌和亚硝酸盐氧化菌数量呈逐渐增加趋势,且均高出水样3~4个数量级;同时对上述样品的16S rRNA基因片段的PCR扩增产物进行变性梯度凝胶电泳(DGGE)分析及其序列同源性分析的结果表明,生物膜和水中都有较高的细菌多样性,同一初始氨氮浓度的滤池中生物膜上的细菌多样性高于水中的.生物滤池中的细菌主要由拟杆菌门的黄杆菌纲和变形菌门的α-、β-、γ-变形菌纲的15种细菌组成.生物膜上的优势菌包括奥雷氏菌属、湖饲养者菌属、泥滩杆菌属、沉积杆菌属、雷辛格氏菌属、冷蛇形菌属和亚硝化单胞菌属等;水体中的优势菌则有明显差异,主要有蛋黄色杆菌属、Nautella,玫瑰杆菌属和一种硫氧化菌等.初始氨氮越高的滤池中,亚硝化单胞菌属的细菌在生物膜上所占比例越高,逐渐成为优势菌之一.实验证实,挂膜初期,提高水体中初始氨氮浓度,有利于硝化细菌的富集和固着,提高生物滤池的除氮效率.%The numbers and composition of bacterial communities in bio-filters of re-circulating mariculmre system were studied. The numbers of total beterotrophic bacteria, ammonium-oxidizing bacteria and nitrateoxidizing bacteria on the matured bio-film samples from the 4 bio-filters with different initial ammonianitrogen concentrations(1#,2#,3#,4#) and from the water sample (5#)of 3# bio-filter were counted. The results showed that, the numbers of ammonia-oxidizing bacteria and nitrate-oxidizing bacteria on the biofilms increased and the number of heterotrophic bacteria declined

  11. 应用PCR-DGGE法评价石斛多糖对肠道微生态失调的调节作用%Regulatory effects of dendrobium polysaccharides on intestinal dysbiosis: an evaluation by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    郭建壮; 成正祥; 祁冬冬; 马淑霞; 杜宁; 赵宏博; 杨景云

    2012-01-01

    目的 从微生态学角度研究石斛多糖治疗肠道微生态失调小鼠的作用及初步机制.方法 盐酸林可霉素灌胃制备肠道菌群失调小鼠模型,应用石斛多糖进行治疗,同时设正常对照组、丽珠肠乐组、阴性对照组,给药7d后处死小鼠,应用PCR-DGGE法检测肠道菌群丰富度、血清IL-2.结果 应用盐酸林可霉素灌胃3d后,小鼠肠道菌群丰富度、血清IL-2降低,持续治疗7d后,石斛多糖治疗小鼠肠道菌群丰富度、血清IL-2增高.结论 石斛多糖具有扶植肠道正常菌群生长,调整菌群失调,提高机体免疫力的作用.%Objective To explore the role and preliminary mechanism of Dendrobium Polysaccharides in treating mice intestinal microflora imbalance from a micro-ecological perspective. Methods Lincomycin hydrochloride was orally administered to induce intestinal microflora imbalance in the mice, after which the mice were treated with Dendrobium Polysaccharides. At the same time, the mice were randomly divided into normal control group, Oral Live Bifodobacterium preparation group and negative control group. After 7 days of treatment with various medicines , the mice were sacrificed and the PCR-DGGE and ELISA were used to detect intestinal flora richness and serum IL-2 respectively. Results After 3 days of oral administration of Lincomycin hydrochloride, there was a decrease in the intestinal flora richness and serum IL-2 of the mice. However, after 7 days of continuous treatment with Dendrobium Polysaccharides, an increase in the intestinal flora richness and serum IL-2 were observed. Conclusion Dendrobium Polysaccharide fosters the growth of normal intestinal flora, has a regulatory effect on intestinal flora, and improves immunity.

  12. Denitrification performance and microbial community structure of a combined WLA-OBCO system.

    Directory of Open Access Journals (Sweden)

    Tinglin Huang

    Full Text Available The contamination of surface water by nitrogen due to fertilizer application and discharge of wastewater is an increasingly serious problem. A multifunctional device, which combines water-lifting and aeration (WLA with oligotrophic biological contact oxidation (OBCO, was developed for pretreatment of raw water to reduce nitrogen. The performance of nitrogen removal and changes in microbial community structure were investigated. The results showed that the combined technique of WLA-OBCO was feasible, and that ammonium, nitrate, total nitrogen and total organic carbon were effectively removed. Meanwhile, nitrite was mostly undetectable. The PCR-DGGE and clone sequencing results revealed that α-proteobacterium was the largest bacterial group, and Pseudomonas strains Y3 and J8 were the dominant bacteria.

  13. 变性梯度胶电泳分析不同喂养方式对早产新生儿肠道菌群的影响%Study of intestinal microbiota between breast- feeding and formula- feeding premature neonates by PCR- DGGE

    Institute of Scientific and Technical Information of China (English)

    李秀云; 兰和魁; 王霞; 符薇; 严奇; 任大明

    2004-01-01

    目的采用变性梯度胶电泳方法(DGGE)研究喂养方式对早产新生儿肠道茵群的影响.方法收集同期6对新生儿1~21 d粪便,直接提取细菌总DNA,扩增16S rDNA V6~V8区后DGGE分离,测序并与EMBL核苷序列数据库进行比较.结果喂养前肠道菌群类似,以梭状芽孢杆菌、链球菌、克雷伯氏茵为主,开奶后母乳喂养儿以双歧杆茵为主,奶粉喂养儿肠道茵群显示其明显的多态性,有双歧杆菌、梭状芽孢杆菌、链球菌、大肠杆茵、克雷伯氏菌、韦荣氏茵、沙雷氏茵以及不经培养细菌.结论喂养方式对早产新生儿茵群的形成及演替有明显影响,PCR-DGGE在多态性,动力性,茵群的演进变化方面提供了更加准确的数据和补充资料.%Objective:To study the difference of intestinal microbiota between breast- feeding and formula feeding premature neonates. Methods:Total DNAs were extracted from the feces of two group neonates. Bacterial communities in two group infants were examined by PCR of 16S rDNA V6 - V8 regions and denaturing gradient gel electrophoresis (DGGE) and by analyzing the sequences of the ribotypes. Results: During the first few days of life the profiles of DGGE were simple, but they became more complex as the bacterial diversity increased with time, especially in formula - feeding infants. Species most closely related to the Bifidobaeterium dominated the intestinal microbiota in breast - feeding infants. Bacterial diversity were more marked in formola - feeding infants than breast - feeding. the bacteria identified included members of genera Bifidobacteria, Clostridium, E. coli, Streptococcus, Uncurtured bacteria, Klesiella, Veillonella, Uncultured fecal bacterium, Serratia. Conclusion: Feeding mode is a important factor affecting developmental intestinal microbiota in premature neonates. PCR - DGGE and 16S rDNA sequence analysis resulted in a dynamic description of bacterial ciloniztion in the infant intestinal

  14. Fungal communities structure during the pile-fermentation process of Fuzhuan brick tea by DGGE technology%用DGGE法初步解析茯砖茶渥堆发酵过程中真菌群落的结构

    Institute of Scientific and Technical Information of China (English)

    刘石泉; 胡治远; 赵运林

    2014-01-01

    为研究茯砖茶发花过程中真菌群落的结构和种类,对茯砖茶渥堆发酵过程中不同时间段黑毛茶样品中真菌群落的18S rDNA高变区进行扩增,对真菌18S rDNA变性梯度凝胶电脉(DGGE)图谱中的条带进行回收、克隆、测序和序列比对.结果表明:茯砖茶渥堆发酵过程中的真菌类型丰富,有好干性酵母(Wallemia sebi)、假丝酵母菌(Candida sp.)、热带假丝酵母(Candida tropicalis)、路德酵母(Lodderomyces sp.)、汉逊德巴利酵母(Debaryomyces hanseniO、毕赤酵母(Pichia kudriavzevii)、酿酒酵母(Saccharomyces cerevisiae)、隐球酵母(Cryptococcus sp.)、牧草红酵母(Rhodotorula graminis)、阿姆斯特丹散囊菌(Eurotium amstelodami)、灰绿曲霉(Aspergillus glaucus)、米赫根毛霉(Rhizomucor miehei)、微小根毛霉(Rhizomucor pusillus)、白地霉(Galactomyces geotrichum)、安大略假单胞菌(Candida ontarioensis)、真皮毛孢子菌(Trichosporon dermatis)、斜卧青霉(Penicillium decumbens)、曲霉(Aspergillus penicillioides)等真菌存在;以渥堆24 h为分界点,真菌群落结构在分界点前后变化较大;真菌群落多样性指数在渥堆0~16h呈升高趋势,>16~24h略有降低,>24h后继续升高,在渥堆后40h上升到最高水平2.348,而渥堆>40~48 h仍然维持在较高水平;在整个渥堆过程中,优势菌路德酵母、汉逊德巴利酵母和次优势菌阿姆斯特丹散囊菌均有出现,在渥堆后期出现了次优势菌好干性酵母、汉逊德巴利酵母和酿酒酵母;比对结果表明,渥堆过程中同时存在3株好干性酵母菌和7株阿姆斯特丹散囊菌,说明在渥堆发酵过程中优势菌种存在多样性.本研究结果表明,采用DGGE指纹图谱能全面、真实地反映茯砖茶渥堆发酵过程中真菌群落的结构和多样性变化.

  15. Analyses of soil fungal community succession under chlorpyrifos stress using PCR-DGGE%聚合酶链反应-变性梯度凝胶电泳分析在毒死蜱胁迫下土壤真菌群落结构演替

    Institute of Scientific and Technical Information of China (English)

    李艳丽; 陈列忠

    2013-01-01

    Chlorpyrifos (CP) is a broad-spectrum,moderately toxic organophosphorus insecticide.It is widely used throughout the world,especially in recent years with the restrictions or eliminations of highly toxic organophosphorus compounds.The fate of CP after a single application in soil and its effects on soil microbial population,microbial functional diversity,microbial respiration,and enzyme activities have been well investigated.However,the influence of CP application on the soil fungal community succession remains unknown.Denaturing gradient gel electrophoresis (DGGE) is currently used in the characterization of soil bacterial and fungal community.DGGE analysis can provide a picture composed of an array of bands with different intensities,and the banding patterns of DGGE are analyzed using Quantity One V4.62 software (Bio-Rad).An Excel worksheet was used to calculate the Shannon-Wiener index (H),and Matlab software (MathWorks) was performed to do principal component analysis (PCA) of DGGE data.The aim of this study was to assess the effect of CP application on soil fungal community using PCR-DGGE based on internal transcribed spacer (ITS) region and 28S rDNA amplification products.After preincubation in the dark for one week at 25 ℃,CP was applied to soils with a predetermined volume of their commercial formulation,following proper dilution with distilled water,to give a final concentration of 5 mg/kg corresponding to the recommended dose.Soil samples received the same amount of sterilized water without CP were used as controls.Each treatment was conducted thrice,and a total of six microcosms were prepared.At 1,7,15,30,45,and60 d after CP treatment,soil samples were collected to detect CP residue in the soil and to extract soil DNA for polymerase chain reaction (PCR)-DGGE analysis.The degradation curve of CP in soil showed that the CP residues in the soil samples were significantly decreased to 2.086,0.355,and 0.008 mg/kg respectively after 7,30 and 60 d of CP

  16. Effect of Lactobacillus plantarum on disordered intestinal flora of mice introduced by antibiotics using PCR-DGGE technology%用DGGE技术分析植物乳杆菌对小鼠肠道菌群失调的影响

    Institute of Scientific and Technical Information of China (English)

    李艺; 孟镇; 钟其顶; 仇凯; 熊正河; 栾同青; 张泽生

    2013-01-01

    This article's aim was to adopt PCR-DGGE method to study the effect of feeding Lactobacillus plantarum to antibiotic intestinal flora in mice on the gut microflora.Female KM mice were continuously fed with cefdinir solution for five days to cause antibiotic-associated intestinal flora in them,and then treated by oral gavage of Lactobacillus plantarum(109CFU/mL) for another 5 days.Feces were abstracted and 16S rDNAbased PCR-DGGE method was used to analyze the influence of Lactobacillus plantarum adjustment process on the microbial community structure and diversity.The main preponderant strips were rubber cutting cloned and sequenced.PCR-DGGE profiles showed that with the extension of the Lactobacillus plantarum feeding time,the richness of the mouse intestinal flora presented a gradual increase in the successionprocess.The richness index(18) and diversity index(2.75) of the intestinal flora after the mice were gavaged using Lactobacillus plantarum for fourth day were the same as the normal ones.DGGE profiles,sequencing results showed that plant lactobacillus control mice intestinal dysbacteriosis mainly manifested in two aspects:selective increase beneficial bacteria such as Bacteroides stercoris,Bacteroides uniformis strain of quantity.Inhibition of pathogenic bacteria such as Clostridium clostridioforme,Pseudomonas stutzeri growth,etc.Results showed that the Lactobacillus plantarum had adjustment effect on intestinal flora disorder caused by cefdinir.Establishment of PCR-DGGE method analysis methods were in order to monitor the dynamic changes of intestinal flora,and to lay the foundation for further study of probiotics on the mechanism of action of the intestinal flora.%采用PCR-DGGE方法研究植物乳杆菌对小鼠肠道失调菌群微生态的影响.选用昆明雌性小鼠建立小鼠抗生素相关性菌群失调模型,灌服植物乳杆菌菌液(109CFU/mL)5d,分离提取小鼠粪便中微生物群落的DNA,通过PCRDGGE技术分析植物乳杆菌调节

  17. Bacterial diversity in rhizosphere soil of soybean: A comparison of RISA, DGGE, and 2D-PAGE techniques%RISA、DGGE和2D-PAGE技术对大豆根际土壤细菌多样性分析的比较

    Institute of Scientific and Technical Information of China (English)

    李刚; 赵建宁; 文都日乐; 杨殿林

    2011-01-01

    采用基于PCR扩增的核糖体间隔区分析(RISA)、变性梯度凝胶电泳(DGGE)和双向电泳(2D-PAGE)3种分子生态学技术对大豆根际土壤细菌多样性比对分析.结果表明:2D-PAGE技术得到的土壤细菌多样性(基因点)最丰富,其次为DGGE技术(基因片段),RISA技术(基因片段)最低.RISA技术得到的条带数最少,但结果稳定性较高,并且实验操作比较简单;DGGE技术得到的条带数较多,具有较高的精度,但误差来源也最多;2D-PAGE技术作为一种新颖的土壤微生物研究方法,可以很好地解决其他2种技术分辨率低的缺点,能够获得丰富的土壤细菌多样性信息,在土壤微生物生态学研究中发挥重要作用,但与前2种技术相比,其操作比较复杂,条件要求相对比较严格.尽管存在不足,2D-PAGE技术在土壤微生物生态学研究领域中已显示出潜在的优势.%The PCR-based RISA, DGGE, and 2D-PAGE were adopted to analyze the bacterial diversity in thizosphere soil of soybean. Most abundant soil bacterial diversity was acquired by 2D-PAGE (gene spots) , followed by DGGE ( gene bands) , and by RISA ( gene bands). The RISA gave the fewest bands. but the result was more stable and the experimental operation was more easy; DGGE obtained more bands and showed good precision, but had more error sources; while 2D-PAGE as a novel soil microbial research method could overcome the low-resolution problem of the other two methods, achieve abundant information of soil bacterial diversity, and play an important role in the research of soil microbial ecology. However, the operation of 2DPAGE was more complicated and required strict conditions, compared with RISA and DGGE. In spite of these disadvantages, 2D-PAGE had shown potential advantages in the research field of soil microbial ecology.

  18. Combination analysis.

    Science.gov (United States)

    Tallarida, Ronald J

    2010-01-01

    This chapter describes quantitative methodology that is directed toward assessing interactions between a combination of agonist drugs that individually produce overtly similar effects. Drugs administered in combination may show exaggerated, reduced or predictable effects that are dependent on the specific drug pair and the doses of t h e constituents. The basisfor quantitating these unusual interactions is the concept of dose equivalence which, in turn, is determined from the individual drug dose-effect relations. A common analytical procedure that follows from dose equivalence uses a graph termed an isobologram. We present here an overview of the isobologram, its use and certain related methods that apply to classifying various drug interactions.

  19. Combining culture-dependent and -independent methodologies for estimation of richness of estuarine bacterioplankton consuming riverine dissolved organic matter.

    Science.gov (United States)

    Kisand, Veljo; Wikner, Johan

    2003-06-01

    Three different methods for analyzing natural microbial community diversity were combined to maximize an estimate of the richness of bacterioplankton catabolizing riverine dissolved organic matter (RDOM). We also evaluated the ability of culture-dependent quantitative DNA-DNA hybridization, a 16S rRNA gene clone library, and denaturing gradient gel electrophoresis (DGGE) to detect bacterial taxa in the same sample. Forty-two different cultivatable strains were isolated from rich and poor solid media. In addition, 50 unique clones were obtained by cloning of the bacterial 16S rDNA gene amplified by PCR from the community DNA into an Escherichia coli vector. Twenty-three unique bands were sequenced from 12 DGGE profiles, excluding a composite fuzzy band of the Cytophaga-Flavobacterium group. The different methods gave similar distributions of taxa at the genus level and higher. However, the match at the species level among the methods was poor, and only one species was identified by all three methods. Consequently, all three methods identified unique subsets of bacterial species, amounting to a total richness of 97 operational taxonomic units in the experimental system. The confidence in the results was, however, dependent on the current precision of the phylogenetic determination and definition of the species. Bacterial consumers of RDOM in the studied estuary were primarily both cultivatable and uncultivable taxa of the Cytophaga-Flavobacterium group, a concordant result among the methods applied. Culture-independent methods also suggested several not-yet-cultivated beta-proteobacteria to be RDOM consumers.

  20. Combination rules

    NARCIS (Netherlands)

    Holicky, M.; Vrouwenvelder, A.C.W.M.

    2002-01-01

    Load combinations specified in EN 1990 for verification of ultimate limit and serviceability limit states in conjunction with the partial factor method are discussed and illustrated by practical examples of typical civil structures. Alternative procedures to identify critical load cases are reviewed

  1. Antifungal combinations.

    Science.gov (United States)

    Vitale, Roxana G; Afeltra, Javier; Dannaoui, Eric

    2005-01-01

    The increase in fungal infections and the change in fungal epidemiology is caused by the extensive use of antifungal agents to treat fungal infections that are being diagnosed in severly immunocompromised hosts. In addition, opportunistic fungal infections resistant to antifungal drugs have become increasingly common, and the armamentarium for treatment remains limited. A possible approach to overcoming these problems is to combine antifungal drugs, especially if the mechanisms of action are different. The in vitro test is the first step to evaluate possible antifungal combinations. In this chapter, the three most frequently used metholodologies are described: checkerboard, E-test, and time-kill curves. The description of each technique and intrepretaion of the results are addressed in detail.

  2. Combining haplotypers

    CERN Document Server

    Kääriäinen, Matti; Lappalainen, Sampsa; Mielikäinen, Taneli

    2007-01-01

    Statistically resolving the underlying haplotype pair for a genotype measurement is an important intermediate step in gene mapping studies, and has received much attention recently. Consequently, a variety of methods for this problem have been developed. Different methods employ different statistical models, and thus implicitly encode different assumptions about the nature of the underlying haplotype structure. Depending on the population sample in question, their relative performance can vary greatly, and it is unclear which method to choose for a particular sample. Instead of choosing a single method, we explore combining predictions returned by different methods in a principled way, and thereby circumvent the problem of method selection. We propose several techniques for combining haplotype reconstructions and analyze their computational properties. In an experimental study on real-world haplotype data we show that such techniques can provide more accurate and robust reconstructions, and are useful for out...

  3. Combination Light

    Science.gov (United States)

    1990-01-01

    The Rayovac TANDEM is an advanced technology combination work light and general purpose flashlight that incorporates several NASA technologies. The TANDEM functions as two lights in one. It features a long range spotlight and wide angle floodlight; simple one-hand electrical switching changes the beam from spot to flood. TANDEM developers made particular use of NASA's extensive research in ergonomics in the TANDEM's angled handle, convenient shape and different orientations. The shatterproof, water resistant plastic casing also draws on NASA technology, as does the shape and beam distance of the square diffused flood. TANDEM's heavy duty magnet that permits the light to be affixed to any metal object borrows from NASA research on rare earth magnets that combine strong magnetic capability with low cost. Developers used a NASA-developed ultrasonic welding technique in the light's interior.

  4. Search Combinators

    CERN Document Server

    Schrijvers, Tom; Wuille, Pieter; Samulowitz, Horst; Stuckey, Peter J

    2012-01-01

    The ability to model search in a constraint solver can be an essential asset for solving combinatorial problems. However, existing infrastructure for defining search heuristics is often inadequate. Either modeling capabilities are extremely limited or users are faced with a general-purpose programming language whose features are not tailored towards writing search heuristics. As a result, major improvements in performance may remain unexplored. This article introduces search combinators, a lightweight and solver-independent method that bridges the gap between a conceptually simple modeling language for search (high-level, functional and naturally compositional) and an efficient implementation (low-level, imperative and highly non-modular). By allowing the user to define application-tailored search strategies from a small set of primitives, search combinators effectively provide a rich domain-specific language (DSL) for modeling search to the user. Remarkably, this DSL comes at a low implementation cost to the...

  5. Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

    Institute of Scientific and Technical Information of China (English)

    SU Zhen-cheng; ZHANG Hui-wen; LI Xin-yu; ZHANG Qin; ZHANG Cheng-gang

    2007-01-01

    Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha-and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.

  6. Combination of culture-independent and culture-dependent molecular methods for the determination of bacterial community of iru, a fermented Parkia biglobosa seeds.

    Science.gov (United States)

    Adewumi, Gbenga A; Oguntoyinbo, Folarin A; Keisam, Santosh; Romi, Wahengbam; Jeyaram, Kumaraswamy

    2012-01-01

    In this study, bacterial composition of iru produced by natural, uncontrolled fermentation of Parkia biglobosa seeds was assessed using culture-independent method in combination with culture-based genotypic typing techniques. PCR-denaturing gradient gel electrophoresis (DGGE) revealed similarity in DNA fragments with the two DNA extraction methods used and confirmed bacterial diversity in the 16 iru samples from different production regions. DNA sequencing of the highly variable V3 region of the 16S rRNA genes obtained from PCR-DGGE identified species related to Bacillus subtilis as consistent bacterial species in the fermented samples, while other major bands were identified as close relatives of Staphylococcus vitulinus, Morganella morganii, B. thuringiensis, S. saprophyticus, Tetragenococcus halophilus, Ureibacillus thermosphaericus, Brevibacillus parabrevis, Salinicoccus jeotgali, Brevibacterium sp. and uncultured bacteria clones. Bacillus species were cultured as potential starter cultures and clonal relationship of different isolates determined using amplified ribosomal DNA restriction analysis (ARDRA) combined with 16S-23S rRNA gene internal transcribed spacer (ITS) PCR amplification, restriction analysis (ITS-PCR-RFLP), and randomly amplified polymorphic DNA (RAPD-PCR). This further discriminated B. subtilis and its variants from food-borne pathogens such as B. cereus and suggested the need for development of controlled fermentation processes and good manufacturing practices (GMP) for iru production to achieve product consistency, safety quality, and improved shelf life.

  7. Combination of culture-independent and culture-dependent molecular methods for the determination of bacterial community of iru, a fermented Parkia biglobosa seeds.

    Directory of Open Access Journals (Sweden)

    Gbenga Adedeji Adewumi

    2013-01-01

    Full Text Available In this study, bacterial composition of iru produced by natural, uncontrolled fermentation of Parkia biglobosa seeds was assessed using culture-independent method in combination with culture-based genotypic typing techniques. PCR-denaturing gradient gel electrophoresis (DGGE revealed similarity in DNA fragments with the two DNA extraction methods used and confirmed bacterial diversity in the sixteen iru samples from different production regions. DNA sequencing of the highly variable V3 region of the 16S rRNA genes obtained from PCR-DGGE identified species related to Bacillus subtilis as consistent bacterial species in the fermented samples, while other major bands were identified as close relatives of Staphylococcus vitulinus, Morganella morganii, B. thuringiensis, Staphylococcus saprophyticus, Tetragenococcus halophilus, Ureibacillus thermosphaericus, Brevibacillus parabrevis, Salinicoccus jeotgali, Brevibacterium sp. and Uncultured bacteria clones. Bacillus species were cultured as potential starter cultures and clonal relationship of different isolates determined using amplified ribosomal DNA restriction analysis (ARDRA combined with 16S-23S rRNA gene internal transcribed spacer (ITS PCR amplification, restriction analysis (ITS-PCR-RFLP and randomly amplified polymorphic DNA (RAPD-PCR. This further discriminated Bacillus subtilis and its variants from food-borne pathogens such as Bacillus cereus and suggested the need for development of controlled fermentation processes and good manufacturing practices (GMP for iru production to achieve product consistency, safety quality and improved shelf life.

  8. Influence of Different DNA Extraction Methods on Microbial Diversity PCR-DGGE Detection of Culture Pond Sendiment%DNA不同提取方法对养殖池塘底泥细菌多样性PCR-DGGE检测的影响

    Institute of Scientific and Technical Information of China (English)

    王宇; 林文辉; 王亚军; 毕晔; 石存斌; 吴淑勤

    2009-01-01

    应用PCR-DGGE技术研究了养殖池塘底泥中细菌DNA 5种提取方法对细菌多样性检测的影响.结果显示:(1)DNA粗提液中腐殖酸与蛋白的纯度无正相关;(2)5种方法提取的DNA粗提液经过纯化后进行PCR均取得良好结果;(3)采用复合破壁方法提取养殖池塘底泥细菌DNA有利于显示细菌多样性;(4)DNA提取方法是影响池塘底泥细菌多样性PCR-DGGE结果的关键因素,与DNA的产量、纯度关系甚微;(5)5种方法相似性高达0.79,在对养殖池塘底泥细菌多样性进行粗略分析时均可使用;(6)本试验中,基于改进的Martin-Laurent法是用于养殖池塘底泥细菌多样性PCR-DGGE研究的较好的总DNA提取方法.%In this research, PCR - DGGE technique was used for studying five different extraction methods of microbial DNA of the pond sediment in difference of microbial diversities. The purpose is to try to find extraction methods of DNA which can be best used to objectively reflect the diversities and advantages of the bacteria of the pond sediment, and to evaluate comprehensively the five extraction methods. The results showed that: DNA in the crude extract of two humic acids and protein purity is of no positive correlation; the crude DNA extract of the five extraction methods, after purification, yields good results with PCR; broken composite method is used in the extraction of microbial DNA in the sediment ponds, helping enhance microbial diversity; DNA extraction method is the key factor of pond sediment microbial diversity by DGGE, and the diversity has poor relationship with the output and size of DNA; the similarity of the five ways is as high as 0.79, so it can be substituted for one another to conduct a rough analysis of mierobia] diversity; the improved Martin-Laurent Act is a better DNA extraction method for PCR -DGGE microbial diversity study in sediment ponds.

  9. Analgesic combinations

    Science.gov (United States)

    Raffa, Robert B.; Pergolizzi, Joseph V.; Tallarida, Ronald J.

    2010-01-01

    When the pathophysiology of a medical condition is multi-modal, i.e., related to multiple physiological causes or mediated by multiple pathways, the optimal strategy can be to use a drug or a combination of drugs that contribute multiple mechanisms to the therapeutic endpoint. In such situations, a rational multi-modal approach can also result in the fewest adverse effects. We discuss the quantitative analysis of multi-modal action using the treatment of pain as a practical example and give examples of its application to some widely used analgesic drugs. PMID:20338825

  10. Effects of organic amendments and mulches on soil microbial communities in quarry restoration under semiarid climate

    Science.gov (United States)

    Luna Ramos, Lourdes; Pastorelli, Roberta; Miralles Mellado, Isabel; Fabiani, Arturo; Bastida López, Felipe; Hernández Fernández, María Teresa; García Izquierdo, Carlos; Solé Benet, Albert

    2015-04-01

    respect to that of reference soil. Fungal communities could be divided into main groups according to the organic amendment. Within each group, GM amendment generated fungal community structures with lower similarities with respect to the other mulch treatments. In contrast to PLFA results, DGGE fingerprints revealed significant influence of the combination of organic amendments and mulches on diversity and composition of soil microbial communities.

  11. Analysis on the Bacterial Diversity in the Dynamic Fermentation System of Corn and Alfalfa Silage by PCR-DGGE%PCR-DGGE方法分析玉米及苜蓿青贮动态发酵体系中菌群多样性

    Institute of Scientific and Technical Information of China (English)

    韩吉雨; 王海荣; 侯先志; 杨凯; 赵子夫; 郭天龙

    2009-01-01

    [Objective] The aim was to discuss the dynamic fermentation process of corn silage and alfalfa silage.[Method] With corn and alfalfa as silage materials, the genome DNA from silage microbe was extracted by benzyl chloride method.The target fragment was amplified by using primers of P2f and P3r.The dynamic fermentation diversity of corn silage and alfalfa silage were studied by PCR-DGGE.[Result] The pH value of corn silage maintained in 4.0-4.5 and alfalfa silage maintained in 5.5-6.0 during fermentation process.PCR-DGGE analysis showed that the similarity of the 2 silages were all high between 0 and 1 d, 3 and 7 d, 20 and 60 d.The 2 silages had basically similar band types.Among them, the band 1, 3, 13, 14, 17, 21 and 22 belonged to all samples and the difference was only in brightness.DGGE result showed that most sequence represented lactic-acid bacteria, and the Lactobacillus was most, followed by Lactococcus and Weissella.[Conclusion] The research laid the foundation for preparation of silage additive.%[目的] 探讨玉米青贮和苜蓿青贮动态发酵过程.[方法] 以玉米和苜蓿为青贮原料,利用氯化苄方法对青贮中微生物基因组DNA进行提取,以P2f和P3r为引物扩增目的片段并利用PCR-DGGE方法对玉米青贮及苜蓿青贮进行动态发酵多样性研究.[结果] 玉米青贮的pH值在发酵过程中维持在4.0~4.5,而苜蓿青贮则维持在5.5~6.0.PCR-DGGE 分析显示2种物料青贮在0和1 d、3和7 d、20 和60 d相似性均很高,并且它们具有基本相似的谱带类型,其中条带 1、3、13、14、17、21、22为所有样品共有,只是亮度上有差异.DGGE研究结果表明大多数序列代表乳酸菌(LAB)类细菌,并以Lactobacillus 类最多;其次为Lactococcus和Weissella.[结论] 该研究为青贮添加剂的制作奠定基础.

  12. Impacts of methamidophos, copper, and their combinations on bacterial community structure and function in black soil

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Huiwen; ZHOU; Qixing; ZHANG; Qianru; ZHANG; Chengg

    2005-01-01

    The potential ecotoxicologial risks of methamidophos, copper, and their combinations on microbial community of black soil ecosystem in the Northeast China were assessed in species richness and structures by using 16S rDNA-PCR-DGGE analysis approach, and functional characteristics at community levels by using BIOLOGGN system analysis method as well as two conventional methods(DHA and SIR). All results of DGGE banding fingerprint patterns(amplified by bacterial specific 16S rDNA V3 high variable region universal primer) indicated that the species richness of bacterial community in tested soil was significantly decreased to different extents by using different concentrations of single methamidophos, copper, especially some of their combinations had worse effects than their corresponding single factors. In addition,the structures of soil bacterial community had been disturbed under all stresses applied in this study because of the enrichment of some species and the disappearance of other species from the bacterial community. The effects of the single factors with lower concentrations on the communiy structure were weaker than those with higher concentrations. Moreover, the bacterial community structures under the combined stresses of methamidophos and copper were significantly different from those of control and their corresponding single factors. The change of DHA and carbon source substrate utilizing fingerprint patterns based on BIOLOGGNsystem were two relatively sensitive directors corresponding to the stress presented in this study. Between methamodophos and copper, there happened the significant joint-toxic actions when they were used in combination on DHA and carbon source substrate utilizing fingerprint patterns of soil bacterial communities. The DHA of soil under the combined stresses was lower than that of the control and that under the single factors, and the BIOLOGGN substrate utilizing patterns of soil treated by combinations were distinctively

  13. 主养草鱼池塘三种混养模式下鱼类肠道菌群PCR-DGGE比较%Comparative on Fish Intestinal Microbiota from Three Polyculture Patterns in Mainly Cultural Grass Carp Pond by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    王琴; 熊邦喜; 朱玉婷; 施培松; 余育和

    2012-01-01

    消化道微生物在宿主生长、营养和健康等方面起到重要的作用.本实验采用基于PCR扩增的变性梯度凝胶电泳(PCR-DGGE)技术比较研究了主养草鱼(Ctenopharyngodon idellus)池塘三种不同混养模式下的鱼类肠道菌群差异.结果表明,三种混养模式下同种鱼的生长率出现显著性差异(P<0.05),而肠道细菌16SrDNA V3区特征片段PCR-DGGE指纹分析显示草鱼的肠道菌群相似性较高(>42.2%);投喂配合饲料的草鱼与摄食浮游生物的鲢(Hypophthalmichthys molitrix)、鳙(Aristichthys nobilis和匙吻鲟(Polyodon spathula)肠道菌群结构相差最大(<19%),鲢和鳙肠道菌群相似性较高(>41.6%),除模式Ⅱ鳙的肠道和匙吻鲟的胃菌群具有较高的相似性(>50.3%)外,匙吻鲟的消化道菌群和鲢鳙的相似性低.实验共回收测序了14条特定DGGE条带中的DNA片段,并进行系统进化分析,结果显示,这14条条带分别归属于4个细菌类群:变形细菌门(Proteobacteria),拟杆菌门(Bacteroidetes),厚壁菌门(Firmicutes)和梭杆菌门(Fusobacteria).研究结果为鱼类混养模式的优化,饲料研发和鱼病防治提供了基础参考资料.%The intestinal microbiota plays an important role in the growth, nutrition and well being of the host, and it would be necessary to know the microflora structure in the gastrointestinal tract and the influence factors. The present study used 16S Rdna polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) technology to investigate the intestinal microbiota diversity of fanned fishes from three polyculture patterns with grass caxp(Ctenopharyngodon idellus) as a major component. The results showed that there was significant differences among special growth rate of the same species from the different polyculture patterns after four months' cultivation and data analysis (P 42.2%) of grass carp intestinal bacteria in different polyculture patterns. The intestinal

  14. 利用PCR-DGGE方法研究添加复合菌剂对堆肥微生物群落的影响%Effects of Adding to Complex Bacteria on Microbial Community of Compost Assessed by PCR-DGGE Techniques

    Institute of Scientific and Technical Information of China (English)

    王晶; 许修宏

    2011-01-01

    为研究接种复合菌剂对堆肥微生物群落变化的影响,以奶牛粪便和稻草为原料进行堆肥试验,设添加复合菌剂BLD(由3株木质纤维素降解细菌组成,经测序鉴定分别为枯草芽孢杆菌、地衣芽孢杆菌、假单胞菌属中未鉴定种)和不加菌剂两个处理,利用传统平板培养与聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)方法相结合研究两种堆肥处理对微生物群落演替的影响.结果表明,基于传统培养方式,微生物数量呈升高-降低-升高-降低的趋势,且细菌数量明显大于真菌数量;DGGE图谱显示,两种堆肥处理的条带数呈现与传统培养相似的变化趋势.接种菌株在堆肥初期成功定殖,高温期成为优势菌株,降温期优势逐渐减弱.接种菌剂增加了堆肥中细菌数量,提高了堆肥微生物群落多样性,从而促进堆肥微生物群落演替,缩短堆肥腐熟时间.%In order to study the influence of inoculated strains on composting microbial community strcture, composting experiment was conducted, which used the cow dung and straw as raw materials. Two groups were designed, bacterial strains were added to one group(code name as BLD, which were composed of three kinds of strains, and sequencing showed that they were B. Subtilis, B.licheniformis and Pseu-domonas), the other was the control. Variation of microbial communities in inoculation and natural composts was studied with the traditional plate-count method and the PCR-DGGE technology. Results indicated that:based on the traditional method, the population of microbes showed wave-like fluctuation: up-down-up-down, and the total bacterial count was significantly more than fungi. The DGGE graphs showed similar trend. And the inoculated strains colonized successfully in the early stage of compost, they became the superior strains in the high temperature phase, the strength of bands reduced in the cooling and maturation phases. Inoculatation could increase the

  15. DNA Preparation for Analyzing Petroleum Contaminated Soil Microorganism by Denaturing Gradient Gel Electrophoresis (DGGE)%适用变性梯度凝胶电泳分析的石油污染土壤微生物DNA模板制备的研究

    Institute of Scientific and Technical Information of China (English)

    韦超英; 杨滨银; 方新湘; 娄恺; 晁群芳

    2011-01-01

    [目的]为了快速、简便和经济地获得理化性质不同的石油污染土壤中微生物总DNA,以用于后续微生物群落结构分析及动态监测.[方法]采用3种提取方法对石油污染土壤中细菌总DNA进行提取,并通过DNA产量、纯度、片段大小、基因组完整性等对提取得到的DNA质量进行评价;并对16S rDNA V3可变区的PCR扩增产物进行DGGE分析.[结果]采用3种方法均能从石油污染土壤中提取得到相应的细菌DNA片段,且针对同一种提取方法,土壤理化性质的差异对DNA提取效果影响不明显,但不同方法提取得到的DNA在浓度和纯度上存在明显差异.采用3种方法提取得到的DNA量分别可达98.3、79.9和43.8 ng/μl.[结论]选取方法1提取基因组DNA并进一步纯化,纯化后的DNA分别采用引物F27/R1492和F357/R518进行16S rDNA及116S rDNA V3可变区的扩增,获得了条带清晰、浓度高、无污染的DNA目的片段;对其PCR扩增产物进行DGGE分析,得到的DGGE图谱可直观反应石油污染土壤中微生物的多样性及优势种群.%[ Objective] In order to obtain total DNA in a rapid high-efficient and economic way from microorganism in petroleum contaminated soil with different properties. The total DNA can be used in the microbial community structural analysis and dynamic monitoring. [Methods] Three DNA extraction methods were used for isolation of total DNA form petroleum contaminated soil and the evaluation of DNA quality was based on the DNA yield, purity, fragment size and genome integrity. The amplification of 16S rDNA V3 variable region and the subsequent a-nalysis of amplified products by DGGE. [Result] The results showed that three methods can extract corresponding DNA fragment from samples , and for the same extraction method , different properties soil had no obvious effect on the DNA extraction; but different methods had obvious distinction in the concentration and purity of extracted DNA. The extracted

  16. Comparison of DGGE,T-RFLP and LH-PCR in the analysis of microbial community diversity for two kinds of activated sludges%DGGE、T-RFLP、LH-PCR对两种活性污泥的微生物种群多样性分析的比较

    Institute of Scientific and Technical Information of China (English)

    孙庆华; 柏耀辉; 赵翠; 温东辉; 唐孝炎

    2009-01-01

    采用基于PCR扩增的分子生态技术DGGE、T-RFLP和LH-PCR,对2种典型污水处理系统中的活性污泥(生活污泥、焦化污泥)进行微生物种群多样性分析;并以此比较3种技术的优劣,提出不同应用条件下研究方法的选择依据.根据实验结果:DGGE得到的条带较多,但误差来源也最多;T-RFLP技术较为灵敏,但需要选择适当的内切酶,严格控制酶切条件,并且文库比对误差较大;而LH-PCR操作简单,结果稳定性较高.虽然目前尚无法判断3种方法的准确性,但LHPCR在活性污泥的微生物种群多样性分析中已显示出潜在优势.%Using three PCR-based molecular ecological techniques,i.e.DGGE,T-RFLP and LH-PCR,the microbial community diversity of activated sludges from two typical wastewater treatment systems(domestic and coking)was investigated.The advantages and disadvantages of the three techniques were compared and the consideration of method selection under different conditions was suggested.DGGE displayed many bands,nevertheless.the sources of error were multiple.T-RFLP was sensitive,but it required suitable endonuclease and reaction condition,and the result from the T-RFLP phylogenetic assignment tool(PAT)was uncertainty to some extent.LH-PCR was characterized by simple operation and stable result.Under the existing technical level.it was still unable to determine the accuracy of the three techniques.However.LH-PCR had displayed a certain potential in the analysis of microbial community diversity for activated sludges.

  17. 应用PCR-DGGE指纹技术研究真空包装火腿切片贮藏过程中的微生物动态变化%Study of the dynamic changes of microorganisms in sliced vacuum-packed cooked ham during storage by PCR-DGGE fingerprinting

    Institute of Scientific and Technical Information of China (English)

    胡萍; 周光宏; 徐幸莲; 韩衍青; 徐宝财; 刘军昌

    2009-01-01

    应用16S rDNA变性梯度凝胶电泳(DGGE)指纹图谱和系统发育分析方法,揭示了火腿切片在真空包装、4 ℃贮藏条件下主要微生物的动态变化.直接从火腿中提取总的细菌DNA,用巢式PCR和降落PCR扩增16S rDNA V3可变区序列,再通过DGGE得到动态变化指纹图谱.DGGE图谱表明,产品在贮藏初期具有丰富的微生物群落,说明污染微生物的多样性,但经过一段时间后,只有少数种类细菌存活并最终成为主导菌群.DGGE优势条带经DNA序列分析表明,代表最相似菌为清酒乳杆菌(Lactobacillus sakei)和弯曲乳杆菌(Lactobacillus curvatus),其次是长膜明串珠菌(Leuconostoc mesenteroides)和非培养的明串珠菌(uncultured Leuconostoc).

  18. PCR-DGGE技术分析混菌发酵乳中马克斯克鲁维酵母与乳酸菌的相互作用%Application of PCR-DGGE to analyze the interaction between Kluyveromyces marxianus and the lactic acid bacteria during fermentation and storage process

    Institute of Scientific and Technical Information of China (English)

    范维; 李路; 姜铁民; 张彧; 闵伟红; 陈历俊

    2015-01-01

    利用变性梯度凝胶电泳(Denaturing Gradient Gel Electrophoresis,DGGE)技术,对混菌发酵及贮藏过程中马克斯克鲁维酵母与乳酸菌之间的相互作用进行分析,进而对整个过程中微生物优势菌群及其稳定性进行跟踪监测.结果表明:混菌发酵及贮藏过程中微生物组成比较稳定,优势菌为嗜热链球菌(Streptococcus thermophilus,ST);发酵过程中,马克斯克鲁维酵母(Kluyveromyces marxianus)的添加对乳酸菌生长起到促进作用,尤其是对保加利亚乳杆菌(Lactobacillus bulgaricus,LB)效果显著,贮藏期间该作用转变为抑制;整个过程乳酸菌的存在对酵母菌的生长具有一定的抑制作用.该研究可为深入探讨乳酸菌与酵母菌共同发酵机理及新型发酵乳制品的开发提供理论基础.

  19. Combination of culture-dependent and culture-independent molecular methods for the determination of lactic microbiota in sucuk.

    Science.gov (United States)

    Kesmen, Z; Yetiman, A E; Gulluce, A; Kacmaz, N; Sagdic, O; Cetin, B; Adiguzel, A; Sahin, F; Yetim, H

    2012-02-15

    In this study, the culture-dependent and culture-independent molecular methods were used for the identification of lactic acid bacteria (LAB) in sucuk a Turkish fermented dry sausage. On the one hand, the PCR-DGGE method targetting the V1 and V3 regions of 16S DNA was applied to DNA that was directly extracted from sucuk samples. On the other hand, rep-PCR fingerprinting was performed for the primary differentiation and grouping of the isolates, and the results were confirmed by sequencing of the 16S rDNA and 16S-23S rDNA intergenic spacer region. As a result of the PCR-DGGE analysis of all the samples, total 8 different lactic acid bacteria were identified, and Lactobacillus sakei, Lactobacillus curvatus and Weissella viridescens were the dominant microbiota among these bacteria. The culture-dependent approach indicated that the majority of the strains belonged to the Lactobacillus genera including Lb. sakei, Lactobacillus plantarum, Lb. curvatus, Lactobacillus brevis, Lactobacillus farciminis and Lactobacillus alimentarius. However, Leuconostoc and Weisella were also detected as minor genera. Again, Lactococcus piscium, Weissella halotolerans, Staphylococcus succinus and the comigrated Staphylococcus piscifermentans/Staphylococcus condimenti/Staphylococcus carnosus group were detected only with the culture-independent method while Lb. plantarum, Leuconostoc mesenteroides and Leuconostoc citreum were identified only by using the culture-dependent method. In the results, it was concluded that the combination of culture-dependent and culture-independent methods was necessary for reliable and detailed investigation of LAB communities in fermented food products.

  20. Analysis of Bacterial Diversity in Rumen of Sika Deer (Cervus nippon) fed Different Forages Using DGGE and T-RLFP%基于DGGE和T-RFLP分析采食不同粗饲料梅花鹿瘤胃细菌区系

    Institute of Scientific and Technical Information of China (English)

    李志鹏; 姜娜; 刘晗璐; 崔学哲; 荆祎; 杨福合; 李光玉

    2014-01-01

    D的各项指数相差较大而且梅花鹿C的指数低于梅花鹿A和B,表明同组不同个体之间存在差异。81、214、272和308 bp的T-RFs为OL组优势条带,90、95、175、273和274 bp的T-RFs为CS组优势条带,161、259、264、266和284 bp的T-RFs为共同条带。根据 MiCAⅢ结果,这些 T-RFs 代表细菌归类于拟杆菌门、厚壁菌门、变形菌门和酸杆菌门。T-RFs图谱聚类表明,4头梅花鹿T-RFs聚为两类,粗饲料来源影响梅花鹿瘤胃细菌T-RFs图谱特征,其中梅花鹿A、B和C的T-RFs特征条带图谱相似。【结论】Prevotella spp.是梅花鹿瘤胃优势细菌,但不同粗饲料影响梅花鹿瘤胃细菌区系组成。%[Objective]Bacterial communities play critical roles in the rumen fermentation of Sika deer (Cervus nippon), while the bacterial composition in the rumen of Sika deer is rarely reported. The objective of present study is to investigate the bacterial diversity in the rumen of Sika deer, which can provide a molecular basis for manipulation of rumen fermentation.[Method]Four two year old male rumen-cannulated Sika deers fed oak leaf (OL group, Sika deer A and B) and corn stover (CS group, Sika deer C and D) based diets were used in the present study. After 30 days of feeding, rumen contents including solid and liquid fractions were sampled, and the microbial genomic DNA was extracted. V3 region of ruminal bacterial 16S rRNA gene and 16S rRNA gene was amplified, which was used in the DGGE and T-RFLP analysis, respectively. The clustering analysis was applied to DGGE results. The dominant bands in DGGE profiles were obtained, and then used to clone sequencing in order to indentify the bacterial communities. The results of T-RFLP were also applied to clustering analysis, and the possible bacterial structure was speculated by Microbial Community AnalysisⅢ (MiCAⅢ) dataset. [Result]The clustering patterns of DGGE revealed that the similarity of bacterial diversity between CS

  1. 变性梯度凝胶电泳方法对慢性阻塞性肺疾病患者呼吸道菌群分析%Analysis of respiratory microbiota in patients with chronic obstructive pulmonary disease by DGGE

    Institute of Scientific and Technical Information of China (English)

    刘雪梅; 杨岚

    2013-01-01

    目的 对慢性阻塞性肺疾病(COPD)稳定期及COPD急性加重期(AECOPD)患者呼吸道菌群进行分析,了解疾病不同阶段的菌群分布特征和变化情况.方法 收集COPD稳定期、AECOPD患者及正常对照组痰标本,用变性梯度凝胶电泳(DGGE)方法分析三组样本的菌群分布情况,了解COPD患者呼吸道菌群分布、多样性及相似性等特征.结果 所有标本对应泳道都可见丰富条带.COPD稳定期组和正常对照组条带多样性类似,AECOPD组明显减少.COPD患者组条带亮度普遍较正常对照组高,部分条带在患者组与正常对照组间位置相同但前者亮度高,部分条带仅存在于患者组.部分条带在三组间位置相同,但亮度从正常对照组至AECOPD组逐渐增加.AECOPD组与稳定期组部分条带位置相同但前者亮度高,部分条带仅存在于AECOPD组.结论 COPD病程不同阶段呼吸道菌群分布及细菌负荷均发生了较大变化.%Objective Analyze the respiratory tract flora of patients with stable COPD and AECOPD,to see flora distribution characteristics and changes at different stages of the disease.Methods Using denaturing gradient gel electrophoresis (DGGE) technology to analyze the sputum samples from patients with stable COPD,AECOPD and normal controls,to see the characteristics of the distribution,diversity and similarity of respiratory tract flora of COPD patients.Results Rich bands were visible from all sputum samples corresponding lanes.The diversity of bands of stable COPD and normal controls was similar,while that of AECOPD patients was significantly reduced.The brightness of bands of COPD patients group were generally higher than that of normal control group.Some bands were in the same locations between the two groups,but the brightness of the COPD patients group was higher,and some were visible only in the COPD patients group.Some bands were in the same locations among the normal control group,stable COPD group and AECOPD group

  2. PCR-DGGE研究Carrousel2000氧化沟工艺调试过程中的微生物多样性%Application of PCR-DGGE to Study Microbial Diversity During the Operating of Carrousel 2000 Oxidation Ditch

    Institute of Scientific and Technical Information of China (English)

    许春红; 刘永德; 赵继红

    2011-01-01

    收集Carrousel 2000型氧化沟工艺启动过程中活性污泥样品,直接提取微生物的基因组DNA并纯化,然后对细菌16S rDNA的V,高变区进行PCR扩增和DGGE分离,通过比较DGGE图谱的相似性来研究工艺调试过程中微生物种群的变化情况.研究表明,活性污泥中具有非常丰富的微生物种群.调试初期水质波动对氧化沟中微生物种群的影响非常明显,但接种的成熟活性污泥中微生物种群能够很快适应新型氧化沟工艺的结构及水力特性.调试从4月开始,4月氧化沟中微生物种群相似性Cs最大值为68.9%,5~6月Cs最大值为70.8%,8月Cs最大值为73.0%,可见氧化沟中微生物种群相似性逐渐增加,直至稳定.在此过程中,系统对COD、氨氮的处理效果同步提高并趋于稳定.综合分析好氧活性污泥在氧化沟中驯化期为2个月.图4表4参12%To reveal microbial diversity of aerobic activated sludge in Carrousel 2000 oxidation ditch, the sludge in the startup of the oxidation ditch was sampled and their genomic DNA was extracted directly and purified, then the 16S rDNA genes (V3 region) were amplified, and denaturing gradient gel electrophoresis (DGGE) was used to detect microbial diversity of the sludge in oxidation ditch starting-up. The DGGE profiles revealed that microbial population in the activated sludge was very rich. Wastewater quality variation at initial stage had obvious effects on the microbial population in oxidation ditch till two months later. But the microbial population in inoculated activated sludge could adapt quickly to structure and hydraulic properties of the new oxidation ditch process. The operation started from April, and the maximal similarity coefficient of the microbial population in oxidation ditch was 68.9% in April, 70.8% from May to June, and 73.0% in August, respectively. This showed that the similarity coefficient of the microbial population increased gradually and remained stable. During

  3. Hydrocodone Combination Products

    Science.gov (United States)

    Codiclear DH® (as a combination product containing Guaifenesin, Hydrocodone) ... EndaCof XP® (as a combination product containing Guaifenesin, Hydrocodone) ... Entuss® (as a combination product containing Guaifenesin, Hydrocodone)

  4. Analysis of intestinal microecology of Litopenaeus vannamei in industrial aquaculture by RFLP and DGGE techniques%应用RFLP和DGGE技术分析工厂化养殖凡纳滨对虾肠道微生物群落特征

    Institute of Scientific and Technical Information of China (English)

    李玉宏; 柴鹏程; 胡修贵; 孙艳; 黄倢; 宋晓玲

    2014-01-01

    本研究应用PCR-RFLP(Polymerase Chain Reaction-Restriction Fragment Length Polymorphism)和PCR-DGGE(Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis)技术,对工厂化养殖的凡纳滨对虾肠道菌群进行多样性分析.RFLP结果显示,8月样品中不同的克隆子为5个,其中以不可培养细菌(Uncuhurable bacteria)为主要优势菌,其次为鲁杰氏菌属菌种Ruegeria spp.和Rhodobacterales spp..依据微生物多样性的覆盖率分析结果表明,所构建16S rDNA克隆文库的覆盖率为97.5%.10月样品中克隆子为8个,其中以不可培养细菌、芽孢杆菌属Bacillus spp.和弧菌属Vibrio spp.为主要优势菌属,其次为Photobacterium spp.和Neptunomonas spp.;所构建16S rDNA克隆文库的覆盖率为90.8%.应用DGGE分析8月和10月对虾肠道样品,菌群以不可培养细菌和弧菌属为主,其次为Streptomyces spp.、Ruegeria spp.、Enterococcus spp.和Photobacterium damselae.

  5. 基于PCR-DGGE指纹图谱川纹笛鲷及圆白鲳消化道壁优势菌群结构比较分析%COMPARISON OF THE PREDOMINANT BACTERIAL COMMUNITY STRUCTURE IN THE GASTROINTESTINAL WALL BETWEEN LUTJANUS SEBAE AND EPHIPPUS ORBIS BASED ON 16S rDNA PCR-DGGE FINGERPRINT

    Institute of Scientific and Technical Information of China (English)

    周志刚; 石鹏君; 姚斌; 何夙旭; 苏永全; 丁兆坤

    2007-01-01

    本文采用免培养的16S rDNA 梯度凝胶电泳技术(DGGE)对集约化海水网箱养殖川纹笛鲷Lutjanus sebae及圆白鲳Ephippus orbis消化道壁优势菌群结构进行了比较分析.研究结果显示川纹笛鲷及圆白鲳消化道壁存在着大量细菌群落,对DGGE指纹图谱聚类分析表明两种鱼肠道壁及胃壁菌群组成相似度高于50%,其中二者肠道壁细菌组成相似性最高(67%),这些可能与两种鱼养殖在同一水域、摄食相同饵料相关,另外通过软件对DGGE指纹带谱相对丰度分析表明同种鱼肠道壁及胃壁具有相同最大优势菌群.同时,两种鱼消化道壁之间在细菌多样性及相对丰度上亦存在明显区别,圆白鲳消化道壁细菌多样性要高于川纹笛鲷,这可能归因于川纹笛鲷与圆白鲳在天然环境中栖息地的差异性.本研究通过首次建立不同海水鱼消化道壁16S rDNA-DGGE指纹图谱及比较分析,为澄清海水鱼消化道壁微生物区系奠定基础.

  6. PCR-DGGE Analysis of the Effect of Natural Composite Preservative on Dynamic Changes of Microorganisms in Cutlassfish (Trichiurus haumela) during Cold Storage%PCR-DGGE指纹技术研究复合保鲜剂对冷藏带鱼贮藏期间微生物变化的影响

    Institute of Scientific and Technical Information of China (English)

    蓝蔚青; 谢晶

    2012-01-01

    为探讨复合保鲜剂的作用机理和延长水产品货架期,应用聚合酶链式反应(PCR).变性梯度凝胶电泳(DGGE)指纹技术研究复合保鲜剂对冷藏带鱼贮藏期间微生物种群多样性演替规律的影响。采用SDS(sodiumdodecylsulfate)化学裂解法,分别从对照组与复合保鲜剂处理组的冷藏带鱼中提取总细菌基因组DNA,同时进行16SrDNA的V3可变区PCR扩增,再通过DGGE得到动态变化的指纹图谱。DGGE图谱表明,产品在贮藏初期具有丰富的微生物群落,说明污染微生物的多样性,但经过一段时间后,只有少数种类细菌存活并最终成为主导菌群;通过对冷藏带鱼DGGE图谱上的主要条带进行测序分析,获得12种细菌。对照组与复合保鲜剂处理组在腐败后期的特定腐败微生物种类具有高度的相似性。嗜冷杆菌为带鱼贮藏初期的优势菌,随着贮藏时间的延长,希瓦氏菌与假单胞菌的比例逐渐增加,在贮藏过程中成为主要优势菌,荧光假单胞菌与弧菌在贮藏期间占有较大比例。同时,冷藏带鱼经复合保鲜剂处理后,其中的希瓦氏菌与假单胞菌受到明显抑制。%To clarify the mechanism of action of natural composite preservative (NCP) and prolong the shelf life of aquatic products, Polymerase chain reaction denaturing gradient gel eleetrophoresis (PCR-DGGE) fingerprinting was used to study the effect of an NCP consisting of chitosan, lysozyme and tea polyphenols in 1.0% acetic acid solution at respective concentrations of 10.0 g/L, 6 × 10^6 U/L and 3.0 g/L on the evolution of diversity of microbial populations in cutlassfish (Trichiurus haumela) during cold storage. SDS pyrolysis method was used for total genomic DNA extraction from control and NCP-treatment samples of cutlassfish, and the V3 variable regions of 16 S rDNA were subjected to PCR amplification for DGGE fingerprinting of dynamic changes. The

  7. 头孢噻肟污染条件下土壤呼吸、部分酶活性的短期响应及土壤细菌PCR-DGGE分析%Short-term response of soil microbial respiration, enzyme activities, bacteria population and PCR-DGGE profiles of bacterial communities to cefotaxime pollution

    Institute of Scientific and Technical Information of China (English)

    姚振飞; 魏松林; 梅丽娟; 胡健

    2013-01-01

    采用常规土壤酶活力测定方法、平板菌落计数法以及PCR-DGGE技术,分析头孢噻肟污染对土壤呼吸作用、部分酶活性、细菌数量以及细菌多样性的短期影响.结果表明:①头孢噻肟明显刺激处理后1~14 d土壤呼吸强度,处理21d后刺激作用消失;头孢噻肟明显提高处理后1、18 d土壤脲酶活性,处理后3、7d抑制作用明显;不同浓度头孢噻肟处理初期,土壤过氧化氢酶活力均受到抑制,随着培养时间的延长抑制率下降,并且低、中浓度头孢噻肟处理分别在处理后3、7d开始表现出对过氧化氢酶一定程度的刺激作用.②培养1~3 d,各处理对土壤细菌数量具有一定的刺激作用,7d后中、高浓度处理对土壤细菌有一定抑制作用,而18 d后各浓度处理土壤细菌数量基本恢复到对照水平.③采用Quantity One 4.6(Bio-Rad)软件,对PCR-DGGE图谱中各处理1、18 d条带进行分析,发现头孢噻肟处理对样品可检测条带数没有影响,但对处理初期细菌优势种群丰度产生影响,此后逐渐恢复到对照水平.总之,头孢噻肟污染对供试土壤微生物活性、细菌数量以及优势种群的丰度具有不同程度的短期影响,但随着时间的延长,影响逐渐消失.%The short-term effect of cefotaxime at three dosage levels:low (LC,10 mg · kg-1),medium (MC,50 mg · kg-1) and high (HC,200 mg· kg-1) on the soil microbial respiration,enzyme activities,bacteria population and PCR-DGGE profiles of bacterial communities were studied by general measuring methods of soil respiraition and enzyme activity,plate culture count methods and PCR-DGGE techniques.Results showed that:① The soil microbial respiration was significantly stimulated by cefotaxime treated after 1 to 14 days but turned to the normal level 21 days after treatment.The soil urease activity was significantly stimulated by cefotaxine treated after 1 day and 18 days but significantly inhibited after 3 days and 7

  8. Evaluation of denaturing gradient gel electrophoresis (DGGE) used ...

    African Journals Online (AJOL)

    user1

    2012-08-08

    Aug 8, 2012 ... systems. Therefore, three primer pairs that amplify different variable regions of the 16S rRNA gene (V1, ... ones include the selection of the primer system, the gradient .... some of the strains with sequence heterogeneity in the.

  9. Microbial community analysis in a combined anaerobic and aerobic digestion system for treatment of cellulosic ethanol production wastewater.

    Science.gov (United States)

    Shan, Lili; Yu, Yanling; Zhu, Zebing; Zhao, Wei; Wang, Haiman; Ambuchi, John J; Feng, Yujie

    2015-11-01

    This study investigated the microbial diversity established in a combined system composed of a continuous stirred tank reactor (CSTR), expanded granular sludge bed (EGSB) reactor, and sequencing batch reactor (SBR) for treatment of cellulosic ethanol production wastewater. Excellent wastewater treatment performance was obtained in the combined system, which showed a high chemical oxygen demand removal efficiency of 95.8% and completely eliminated most complex organics revealed by gas chromatography-mass spectrometry (GC-MS). Denaturing gradient gel electrophoresis (DGGE) analysis revealed differences in the microbial community structures of the three reactors. Further identification of the microbial populations suggested that the presence of Lactobacillus and Prevotella in CSTR played an active role in the production of volatile fatty acids (VFAs). The most diverse microorganisms with analogous distribution patterns of different layers were observed in the EGSB reactor, and bacteria affiliated with Firmicutes, Synergistetes, and Thermotogae were associated with production of acetate and carbon dioxide/hydrogen, while all acetoclastic methanogens identified belonged to Methanosaetaceae. Overall, microorganisms associated with the ability to degrade cellulose, hemicellulose, and other biomass-derived organic carbons were observed in the combined system. The results presented herein will facilitate the development of an improved cellulosic ethanol production wastewater treatment system.

  10. Birth control pills - combination

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000655.htm Birth control pills - combination To use the sharing features on ... both progestin and estrogen. What Are Combination Birth Control Pills? Birth control pills help keep you from ...

  11. Severe Combined Immunodeficiency (SCID)

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Severe Combined Immunodeficiency (SCID) SCID is a group of rare disorders ... life-saving treatments. Why Is the Study of Severe Combined Immunodeficiency (SCID) a Priority for NIAID? SCID is a ...

  12. Application of PCR-DGGE to analysis of microbial community structure in aerobic unit of A~2/O process%PCR-DGGE技术解析A~2/O工艺好氧单元中微生物群落结构

    Institute of Scientific and Technical Information of China (English)

    吕晶华; 马挺; 郑先强; 段云霞; 李召雨

    2012-01-01

    应用PCR-DGGE方法,追踪了汉沽工业废水处理中好氧工艺的活性污泥系统中微生物群落结构动态变化过程及其微生物群落结构组成。研究结果表明:系统中的微生物群落结构随水质变化而变化,随着培养时间的延长,微生物群落结构趋于稳定,分别属于5大类群,与γ、δ、α、ε变形杆菌(Proteobacterias)、芽孢杆菌(Bacilli)的亲缘关系较近。其中γ变形杆菌是该废水处理过程中的主要菌群,包括Pseudomonas sp.、Rheinheimera sp.、Citrobacter sp.、Klebsiella sp.、Enterbacte-riaceae、Stenotrophomonas maltophilia、Acinetobacter。在整个系统中uncultured Pseudomonas sp.、Halobacillus sp.、Pseudomonassp.、Pseudomonas stutzeri、Acinetobacter sp.可稳定存在于系统中,为该污水处理系统中的优势微生物。因此,提高Halobacillussp.、Pseudomonas sp.、Pseudomonas stutzeri、Acinetobacter sp.菌属在系统中的数量和质量,有利于提高废水生化处理的效果。%The dynamic process and the microbial community structure in the aerobic activated sludge system of the industrial wastewater treatment were traced by the PCR-DGGE technology.The results show that the microbial community structure changes with the water quality in the system and becomes stable as the incubation time increasing.The microbial community structure is mainly composed of five categories which respectively have close relationships with the γ,δ,α,ε Proteobacterias,Bacilli.γ Proteobacterium is the main microbial community,which including Pseudomonas sp.,Rheinheimera sp.,Citrobacter sp.,Klebsiella sp.,Enterbacteriaceae,Stenotrophomonas maltophilia,Acinetobacter.Five bacteria including uncultured Pseudomonas sp.,Halobacillus sp.,Pseudomonas sp.,Pseudomonas stutzeri,Acinetobacter sp.can exist stably in the system and become dominant microorganisms.So the effect of wastewater treatment can be improved by improving quantity and quality of the dominant

  13. COMBINE 2 seminar

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt; Jacobsen, Kim

    1995-01-01

    A seminar about the COMBINE project was described. Further, the project was described in generel, i.e. the COMBINE´s data model (IDM), the data exchange system (DES) and the different I/O-systems included in COMBINE 2......A seminar about the COMBINE project was described. Further, the project was described in generel, i.e. the COMBINE´s data model (IDM), the data exchange system (DES) and the different I/O-systems included in COMBINE 2...

  14. Embodied Conceptual Combination

    Directory of Open Access Journals (Sweden)

    Dermot eLynott

    2010-11-01

    Full Text Available Conceptual combination research investigates the processes involved in creating new meaning from old referents. It is therefore essential that embodied theories of cognition are able to explain this constructive ability and predict the resultant behaviour. However, by failing to take an embodied or grounded view of the conceptual system, existing theories of conceptual combination cannot account for the role of perceptual, motor and affective information in conceptual combination. In the present paper, we propose the Embodied Conceptual Combination (ECCo model to address this oversight. In ECCo, conceptual combination is the result of the interaction of the linguistic and simulation systems, such that linguistic distributional information guides or facilitates the combination process, but the new concept is fundamentally a situated, simulated entity. So, for example, a cactus beetle is represented as a multimodal simulation that includes visual (e.g., the shiny appearance of a beetle and haptic (e.g., the prickliness of the cactus information, all situated in the broader location of a desert environment under a hot sun, and with (at least for some people an element of creepy-crawly revulsion. The ECCo theory differentiates interpretations according to whether the constituent concepts are destructively, or nondestructively, combined in the situated simulation. We compare ECCo to other theories of conceptual combination, and discuss how it accounts for classic effects in the literature.

  15. Effective Nutritional Supplement Combinations

    Science.gov (United States)

    Cooke, Matt; Cribb, Paul J.

    Few supplement combinations that are marketed to athletes are supported by scientific evidence of their effectiveness. Quite often, under the rigor of scientific investigation, the patented combination fails to provide any greater benefit than a group given the active (generic) ingredient. The focus of this chapter is supplement combinations and dosing strategies that are effective at promoting an acute physiological response that may improve/enhance exercise performance or influence chronic adaptations desired from training. In recent years, there has been a particular focus on two nutritional ergogenic aids—creatine monohydrate and protein/amino acids—in combination with specific nutrients in an effort to augment or add to their already established independent ergogenic effects. These combinations and others are discussed in this chapter.

  16. 螺旋粉虱成虫体内细菌群落多样性的PCR-DGGE和16S rRNA文库序列分析%Bacterial community in Aleurodicus dispersus (Hemiptera: Aleyrodidae) estimated by PCR-DGGE and 16S rRNA gene library analysis

    Institute of Scientific and Technical Information of China (English)

    王甸洪; 吴伟坚; 符悦冠

    2012-01-01

    To understand the bacterial diversity and the dominant types of bacteria in the spiraling whitefly, Aleurodicus dispersus Russell, bacterial communities present in both sexes of A. dispersus collected from Psidium guajava in Hainan were characterized using 16S rDNA-polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rRNA gene clone libraries. The partial bacterial 16S rRNA gene fragment was amplified with PCR, and the clone libraries were constructed. Polymerase chain reaction-restriction fragment length polymorphism ( PCR-RFLP) was performed by digestion of the 16S rRNA gene, and each unique restriction fragment polymorphism pattern was designated as an operational taxonomic unit ( OUT ). A total of 10 OTUs were identified from samples of both sexes of A. dispersus. Phylogenetic trees of bacterial 16S rRNA nucleotide sequences were constructed. Phylogenetic analysis revealed that Zymobacter, Arsenophonus, Pantoea, and Pseudomonas are the most dominant groups in both male and female adults of A. dispersus. Candidatus Portiera aleyrodidarum and Arsenophonus sp., possibly the endosymbionts of A. dispersus, were detected in all samples. These bacteria may play synergetic roles in development, reproduction and sex-ratio control of the whitefly.%为了解螺旋粉虱Aleurodicus dispersus体内细菌多样性和主要优势菌群结构,用PCR-DGGE和16S rRNA文库对采白于海南省番石榴上螺旋粉虱雌、雄成虫体内的细菌群落进行了分析.用PCR扩增体内细菌16S rRNA基因,构建雌、雄虫克隆文库;再用限制性片段长度多态性(restriction fragment length polymorphism,RFLP)方法从文库中筛选不同16S rRNA基因图谱,根据图谱对克隆子进行分型.从螺旋粉虱雌、雄两个样品中共获得10种分类操作单元(operational taxonomic unit,OTUs).以16S rRNA基因为基础构建系统发育树,系统发育分析表明,螺旋粉虱雌、雄成虫体内优势菌群主要为发酵菌

  17. Microbial diversity in Diaphorina citri( Homoptera: Psyllidae) estimated by 16S rDNA analysis using DGGE and RFLP%基于16S rDNA序列的柑桔木虱体内共生菌多样性研究

    Institute of Scientific and Technical Information of China (English)

    殷幼平; 刘婷婷; 田圣超; 胡修峰; 吴东; 王中康

    2011-01-01

    昆虫消化道内是一个复杂的微生态系统,有大量的微生物存在.这些微生物对寄主发育、营养吸收和防御方面都起着重要的作用.本文利用基于16S rRNA基因的PCR-RFLP指纹图谱法和变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)的方法对柑桔黄龙病虫-媒柑桔木虱Diaphorina citri体内细菌菌群多样性进行了研究.经PCR-RFLP分析显示31条序列与变形菌门的假单胞菌科、肠杆菌科、黄单胞菌科、伯克氏菌科、立克次氏菌科和根瘤菌科细菌具有较高同源性.柑桔木虱内共生细菌的优势菌群依次为合胞体共生菌(syncytiumendosymbiont)(同源性99%,5条序列,分离频率31%)、Candidatus Carsonella ruddii和Mycetocyte内共生菌(同源性98%,5条序列,分离频率31%)以及亚洲韧皮杆菌(Candidatus Liberibacter asiaticus)和内共生菌Wolbachia.对柑桔木虱内生细菌16S rDNA V3区序列的PCR-DGGE分析,条带相似性的UPMAGA聚类分析表明,采自九里香Murraya paniculata的柑桔木虱内生细菌大多聚为一支,而来自柑桔的聚在另一支,说明寄主差异对柑桔木虱内生细菌菌群构成的影响大于地理位置的影响.将PCR-DGGE条带测序,序列经GenBank序列比对发现柑桔木虱内生细菌主要属于变形菌门假单胞菌科、立克次氏菌科、肠杆菌科、黄单胞菌科以及厚壁菌门链球菌科和芽孢杆菌科.合胞体共生菌(条带3-4)因其稳定存在于木虱体内且不随柑桔木虱寄主和地理位置的改变而变化,可能是柑桔木虱体内的优势共生菌;内共生细菌Wolbachia也在柑桔木虱内稳定存在,表明我国柑桔木虱感染Wolbachia是普遍现象.PCR-RFLP和PCR-DGGE两种方法相结合较好地反映了柑桔木虱内生细菌菌群的多样性,而且均显示出柑桔木虱内的合胞体共生菌是主要的优势菌群.

  18. Different methanotrophic potentials in stratified polar fjord waters (Storfjorden, Spitsbergen identified by using a combination of methane oxidation techniques

    Directory of Open Access Journals (Sweden)

    S. Mau

    2013-04-01

    Full Text Available The bacterially mediated aerobic methane oxidation (MOx is a key mechanism in controlling methane (CH4 emissions from the world's oceans to the atmosphere. In this study, we investigated MOx in the Arctic fjord Storfjorden (Spitsbergen by applying a combination of radio-tracer based incubation assays (3H-CH4 and 14H-CH4, stable C-CH4 isotope measurements, and molecular tools (16S rRNA DGGE-fingerprinting, pmoA- and mxaF gene analyses. Strofjorden is stratified in the summertime with melt water (MW in the upper 60 m of the water column, Arctic water (ArW between 60–100 m and brine-enriched shelf water (BSW down to 140 m. CH4 concentrations were supersaturated with respect to the atmospheric equilibrium (∼3 nM throughout the water column, increasing from ∼20 nM at the surface to a maximum of 72 nM at 60 m and decreasing below. MOx rate measurements at near in situ CH4 concentrations (here measured with 3H-CH4 raising the ambient CH4 pool by −1 at 60 m followed by a decrease in the deeper ArW/BSW. In contrast, rate measurements with 14H-CH4 at elevated CH4 concentrations (incubations were spiked with ∼450 nM of 14H-CH4, providing an estimate of the CH4 oxidation potential showed comparably low turnover rates (−1 at 60 m, but peaked in ArW/BSW at ∼100 m water depth, concomitant with increasing 14C-values in the residual CH4 pool. Our results indicate that the MOx community in the surface MW is adapted to relatively low CH4 concentrations. In contrast, the activity of the deep water MOx community is relatively low at the ambient, summertime CH4 concentrations but has the potential to increase rapidly in response to CH4 availability. A similar distinction between surface and deep water MOx is also suggested by our molecular analyses. Although, we found pmoA and maxF gene sequences throughout the water column attesting the ubiquitous presence of MOx communities in Storfjorden, deep water amplicons of pmoA and maxF were unusually long

  19. Resonant High Power Combiners

    CERN Document Server

    Langlois, Michel; Peillex-Delphe, Guy

    2005-01-01

    Particle accelerators need radio frequency sources. Above 300 MHz, the amplifiers mostly used high power klystrons developed for this sole purpose. As for military equipment, users are drawn to buy "off the shelf" components rather than dedicated devices. IOTs have replaced most klystrons in TV transmitters and find their way in particle accelerators. They are less bulky, easier to replace, more efficient at reduced power. They are also far less powerful. What is the benefit of very compact sources if huge 3 dB couplers are needed to combine the power? To alleviate this drawback, we investigated a resonant combiner, operating in TM010 mode, able to combine 3 to 5 IOTs. Our IOTs being able to deliver 80 kW C.W. apiece, combined power would reach 400 kW minus the minor insertion loss. Values for matching and insertion loss are given. The behavior of the system in case of IOT failure is analyzed.

  20. Severe Combined Immunodeficiency Disorders.

    Science.gov (United States)

    Chinn, Ivan K; Shearer, William T

    2015-11-01

    Severe combined immunodeficiency disorders represent pediatric emergencies due to absence of adaptive immune responses to infections. The conditions result from either intrinsic defects in T-cell development (ie, severe combined immunodeficiency disease [SCID]) or congenital athymia (eg, complete DiGeorge anomaly). Hematopoietic stem cell transplant provides the only clinically approved cure for SCID, although gene therapy research trials are showing significant promise. For greatest survival, patients should undergo transplant before 3.5 months of age and before the onset of infections. Newborn screening programs have yielded successful early identification and treatment of infants with SCID and congenital athymia in the United States.

  1. Combinators for Paraconsistent Attitudes

    DEFF Research Database (Denmark)

    Villadsen, Jørgen

    2001-01-01

    In order to analyse the semantics of natural language sentences a translation into a partial type logic using lexical and logical combinators is presented. The sentences cover a fragment of English with propositional attitudes like knowledge, belief and assertion. A combinator is a closed term...... used for embedded sentences expressing propositional attitudes, thereby allowing for inconsistency without explosion (also called paraconsistency), and is based on a few key equalities for the connectives giving four truth values (truth, falsehood, and undefinedness with negative and positive polarity...

  2. Lefunomide in combination therapy

    NARCIS (Netherlands)

    Kalden, J.R.; Smolen, J.S.; Emery, P.; Riel, P.L.C.M. van; Dougados, M.; Strand, C.V.; Breedveld, F.C.

    2004-01-01

    In most studies of disease modifying antirheumatic drug therapy, in combination with either leflunomide or biological agents, patients are given an additional agent after they have failed treatment with methotrexate (MTX). This review of clinical studies shows that leflunomide is clinically efficaci

  3. Combination treatment for hypertension

    African Journals Online (AJOL)

    On average, one in four adults has hypertension.1 This figure is higher in certain regions of the world, .... doses favours the development of diabetes and should be ... New and old evidence strongly supports combination treatment .... cardiovascular death, stroke and myocardial infarction, cognitive function and dementia.

  4. Coherently combining antennas

    Science.gov (United States)

    Dybdal, Robert B. (Inventor); Curry, Samuel J. (Inventor)

    2009-01-01

    An apparatus includes antenna elements configured to receive a signal including pseudo-random code, and electronics configured to use the pseudo-random code to determine time delays of signals incident upon the antenna elements and to compensate the signals to coherently combine the antenna elements.

  5. Why combine logics?

    NARCIS (Netherlands)

    Blackburn, P.; Rijke, M. de

    1995-01-01

    Combining logics has become a rapidly expanding enterprise that is inspired mainly by concerns about modularity and the wish to join together tailored made logical tools into more powerful but still manageable ones. A natural question is whether it offers anything new over and above existing standar

  6. Combination Chemotherapy for Influenza

    Directory of Open Access Journals (Sweden)

    Robert G. Webster

    2010-07-01

    Full Text Available The emergence of pandemic H1N1 influenza viruses in April 2009 and the continuous evolution of highly pathogenic H5N1 influenza viruses underscore the urgency of novel approaches to chemotherapy for human influenza infection. Anti-influenza drugs are currently limited to the neuraminidase inhibitors (oseltamivir and zanamivir and to M2 ion channel blockers (amantadine and rimantadine, although resistance to the latter class develops rapidly. Potential targets for the development of new anti-influenza agents include the viral polymerase (and endonuclease, the hemagglutinin, and the non-structural protein NS1. The limitations of monotherapy and the emergence of drug-resistant variants make combination chemotherapy the logical therapeutic option. Here we review the experimental data on combination chemotherapy with currently available agents and the development of new agents and therapy targets.

  7. Combined XRD and XAS

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlich, S.N.; Hanson, J.C.; Lopez Camara, A.; Barrio, L.; Estrella, M.; Zhou, G.; Si, R.; Khalid, S. & Wang, Q.

    2010-11-24

    X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) are complementary techniques for investigating the structure of materials. XRD probes long range order and XAFS probes short range order. We have combined the two techniques at one synchrotron beamline, X18A at the NSLS, allowing samples to be studied in a single experiment. This beamline will allow for coordinated measurements of local and long range structural changes in chemical transformations and phase transitions using both techniques.

  8. Combined XRD and XAS

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlich, S.N., E-mail: ehrlich@bnl.gov [NSLS, Brookhaven National Laboratory, Upton, NY 11973 (United States); Hanson, J.C.; Lopez Camara, A.; Barrio, L.; Estrella, M.; Zhou, G.; Si, R. [Chemistry Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Khalid, S. [NSLS, Brookhaven National Laboratory, Upton, NY 11973 (United States); Wang, Q. [Synchrotron Catalysis Consortium, University of Delaware, Newark, DE 19716 (United States)

    2011-09-01

    X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) are complementary techniques for investigating the structure of materials. XRD probes long range order and XAFS probes short range order. We have combined the two techniques at one synchrotron beamline, X18A at the NSLS, allowing samples to be studied in a single experiment. This beamline will allow for coordinated measurements of local and long range structural changes in chemical transformations and phase transitions using both techniques.

  9. Transfer function combinations

    KAUST Repository

    Zhou, Liang

    2012-10-01

    Direct volume rendering has been an active area of research for over two decades. Transfer function design remains a difficult task since current methods, such as traditional 1D and 2D transfer functions, are not always effective for all data sets. Various 1D or 2D transfer function spaces have been proposed to improve classification exploiting different aspects, such as using the gradient magnitude for boundary location and statistical, occlusion, or size metrics. In this paper, we present a novel transfer function method which can provide more specificity for data classification by combining different transfer function spaces. In this work, a 2D transfer function can be combined with 1D transfer functions which improve the classification. Specifically, we use the traditional 2D scalar/gradient magnitude, 2D statistical, and 2D occlusion spectrum transfer functions and combine these with occlusion and/or size-based transfer functions to provide better specificity. We demonstrate the usefulness of the new method by comparing to the following previous techniques: 2D gradient magnitude, 2D occlusion spectrum, 2D statistical transfer functions and 2D size based transfer functions. © 2012 Elsevier Ltd.

  10. Wind-hydro combinations

    Energy Technology Data Exchange (ETDEWEB)

    Stregger, D.L.; Fisher, W.H.

    1980-06-01

    A study was undertaken to investigate the technical and economic viability of a generalized system composed of a wind-electric and hydroelectric system interacting together to provide firm power to a grid, and to determine limits in the extent to which such a combination can be effected. Several scenarios were considered, including: a farm of horizontal axis wind turbines with various generator ratings, generating into a grid; the same wind turbine generator used to pump water into a hydroelectric plant reservoir; and a cursory examination of mechanical pumping with wind energy to increase the water supply of a hydroelectric project. The review of the state-of-the-art indicated that the scenarios investigated represent the most practical utility applications of wind-hydro combinations. The present state-of-the-art is more advanced for multi-megawatt horizontal axis tubines than for vertical axis wind turbines. The utilization factor, on a monthly determination, of the firm wind energy varies with the shape of the hydrograph, load and the wind regimes. Across Canada it was found to vary from a low of 79% to a maximum of 100%. The most important parameter in the economic evaluation of the break-even costs of wind-hydro generation is the cost of alternative supplies of energy. The regions of Canada where wind-hydro combinations appear to be within economic limits at present cost levels are Newfoundland, assuming a oil-fired thermal alternative, and isolated areas such as the Northwest Territories, assuming a diesel alternative. 67 refs., 12 figs., 13 tabs.

  11. Coherent laser beam combining

    CERN Document Server

    Brignon, Arnaud

    2013-01-01

    Recently, the improvement of diode pumping in solid state lasers and the development of double clad fiber lasers have allowed to maintain excellent laser beam quality with single mode fibers. However, the fiber output power if often limited below a power damage threshold. Coherent laser beam combining (CLBC) brings a solution to these limitations by identifying the most efficient architectures and allowing for excellent spectral and spatial quality. This knowledge will become critical for the design of the next generation high-power lasers and is of major interest to many industrial, environme

  12. Combine Harvester Simulator

    DEFF Research Database (Denmark)

    Vilmann, Ole; Sørlie, James Arnold

    1999-01-01

    A simulator for training pilots in the operation of a modern high-tech combine harvester is presented. The new simulator application is based on DMI´s well-known DMS maritime simulator architecture. Two major challenges have been encountered in the development of the simulator: 1) interfacing...... the simulator software and the harvester hardware, and 2) the visual image generation system. Aims of the project have been to promote technology transfer from DMI´s maritime simulator to new application areas, to develop a state-of-the-art pilot training environment, and to utilise the state......-of-the-art in objec-oriented graphics programming technologies....

  13. Optimal Antihypertensive Combination Treatments

    Directory of Open Access Journals (Sweden)

    Massimo Volpe

    2012-03-01

    Full Text Available Over the past three decades it has been consistently shown that optimal blood pressure (BP control significantly reduced cardiovascular (CV morbidity and mortality [1]. Despite solid evidence in favour of benefits derived from BP reductions, however, hypertension control in treated hypertensive patients remains suboptimal worldwide [2, 3]. In addition, proportions of diagnosed and treated hypertensive patients remain largely unchanged over the last two decades[4]. Multiple factors may be advocated to explain this observation, including variation in healthcare access and availability [5, 6], attitudes amongst clinicians towards hypertension [7, 8], inaccuracy in BP measurements [9] and underuse or under dosage of antihypertensive drugs in both monotherapy and in combination therapy [10, 11].On the basis of these considerations, it is beyond the aim of this article to discuss the socioeconomic impact on healthcare and BP measurement techniques. Instead it will seek to explain the importance of attaining early optimal BP control and the use of combination therapy as a new paradigm for the modern clinical management of hypertension.

  14. Combined solar collector

    OpenAIRE

    Voznyak, O.; Shapoval, S.; Pona, O.; Vengryn, I.

    2014-01-01

    In this article was analyzing the efficiency of the combined solar collector for heating buildings. This enhances the efficiency of solar system by increasing the area of the absorption of solar energy. There are describes the results of the research on solar radiation input on a combined solar collector. Проаналізовано ефективність використання комбінованого сонячного колектора для теплопостачання будівель. Він забезпечує підвищення ефективності геліосистеми за рахунок збільшення площі погли...

  15. Combining classical metrology models

    Directory of Open Access Journals (Sweden)

    Francisco Roldán

    2013-11-01

    Full Text Available The results obtained in the graphic analysis of the modulation of the Cuarto Real de Santo Domingo building in Granada, Spain, (ROLDÁN, 2011 have provided new insights to further approach the research on possible use the double-scale in historical monumental architecture. We propose the characterization of the singularities of the system, from the implications and graphic representation required by the metrological scheme identified, as well as the variety of typologies that are presented in their modular frames, and the iterative combination of two-scale modules which allow operational approximations to fractions and ratios not explicitly present in the system.

  16. Combined Heat and Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    At their 2007 Summit in Heiligendamm, G8 leaders called on countries to 'adopt instruments and measures to significantly increase the share of combined heat and power (CHP) in the generation of electricity.' As a result, energy, economic, environmental and utility regulators are looking for tools and information to understand the potential of CHP and to identify appropriate policies for their national circumstances. This report forms the first part of the response. It includes answers to policy makers' questions about the potential economic, energy and environmental benefits of an increased policy commitment to CHP. It also includes for the first time integrated IEA data on global CHP installations, and analyses the benefits of increased CHP investment in the G8+5 countries. A companion report will be produced later in 2008 to document best practice policy approaches that have been used to expand the use of CHP in a variety of countries.

  17. Combined PET/MRI

    DEFF Research Database (Denmark)

    Bailey, D. L.; Pichler, B. J.; Gückel, B.

    2015-01-01

    This paper summarises key themes and discussions from the 4th international workshop dedicated to the advancement of the technical, scientific and clinical applications of combined positron emission tomography (PET)/magnetic resonance imaging (MRI) systems that was held in Tübingen, Germany, from...... February 23 to 27, 2015. Specifically, we summarise the three days of invited presentations from active researchers in this and associated fields augmented by round table discussions and dialogue boards with specific topics. These include the use of PET/MRI in cardiovascular disease, paediatrics, oncology......, neurology and multi-parametric imaging, the latter of which was suggested as a key promoting factor for the wider adoption of integrated PET/MRI. Discussions throughout the workshop and a poll taken on the final day demonstrated that attendees felt more strongly that PET/MRI has further advanced in both...

  18. [Influence of Different Straws Returning with Landfill on Soil Microbial Community Structure Under Dry and Water Farming].

    Science.gov (United States)

    Lan, Mu-ling; Gao, Ming

    2015-11-01

    Based on rice, wheat, corn straw and rape, broad bean green stalk as the research object, using phospholipid fatty acid (PLFA) method, combining principal component analysis method to study the soil microbial quantity, distribution of flora, community structure characteristics under dry and water farming as two different cultivated land use types. The PLFA analysis results showed that: under dry farming, total PLFA quantity ranged 8.35-25.15 nmol x g(-1), showed rape > broad bean > corn > rice > wheat, rape and broad bean significantly increased total PLFA quantity by 1.18 and 1.08 times compared to the treatment without straw; PLFA quantity of bacterial flora in treatments with straws was higher than that without straw, and fungal biomass was significantly increased, so was the species richness of microbial community. Under water faming, the treatments of different straws returning with landfill have improved the PLFA quantity of total soil microbial and flora comparing with the treatment without straw, fungi significantly increased, and species richness of microbial communities value also increased significantly. Total PLFA quantity ranged 4.04-22.19 nmol x g(-1), showed rice > corn > wheat > broad bean > rape, which in rape and broad bean treatments were lower than the treatment without straw; fungal PLFA amount in 5 kinds of straw except broad bean treatment was significantly higher than that of the treatment without straw, bacteria and total PLFA quantity in broad bean processing were significantly lower than those of other treatments, actinomycetes, G+, G- had no significant difference between all treatments; rice, wheat, corn, rape could significantly increase the soil microbial species richness index and dominance index under water faming. The results of principal component analysis showed that broad bean green stalk had the greatest impact on the microbial community structure in the dry soil, rape green stalk and wheat straw had the biggest influence on

  19. Combined application of Triton X-100 and Sinorhizobium sp. Pb002 inoculum for the improvement of lead phytoextraction by Brassica juncea in EDTA amended soil.

    Science.gov (United States)

    Di Gregorio, Simona; Barbafieri, Meri; Lampis, Silvia; Sanangelantoni, Anna Maria; Tassi, Eliana; Vallini, Giovanni

    2006-04-01

    The process of EDTA-assisted lead phytoextraction from the Bovisa (Milan, Italy) brownfield soil was optimized in microcosms vegetated with Brassica juncea. An autochthonous plant growth-promoting rhizobacterium (PGPR), Sinorhizobium sp. Pb002, was isolated from the rhizosphere of B. juncea grown on the Pb-contaminated soil in presence of 2 mM EDTA. The strain was augmented (10(8) CFU g(-1) soil) in vegetated microcosms to stimulate B. juncea biomass production and, hence, its phytoextraction potential. Triton X-100 was also added to microcosms at 5 and 10 times the critical micelle concentration (cmc) to increase the permeability of root barriers to the EDTA-Pb complexes. Triton X-100 amendment determined an increase in Pb concentration within plant tissues. However it contextually exerted a phytotoxic effect. Sinorhizobium sp. Pb002 augmentation was crucial to plant survival in presence of both bioavailable lead and Triton X-100. The combination of the two treatments produced up to 56% increase in the efficiency of lead phytoextraction by B. juncea. The effects of these treatments on the structure of the soil bacterial community were evaluated by 16S rDNA denaturing gradient gel electrophoresis (DGGE).

  20. Identifying fermenting bacteria in anoxic tidal-flat sediments by a combination of microcalorimetry and ribosome-based stable-isotope probing.

    Science.gov (United States)

    Graue, Jutta; Kleindienst, Sara; Lueders, Tillmann; Cypionka, Heribert; Engelen, Bert

    2012-07-01

    A novel approach was developed to follow the successive utilization of organic carbon under anoxic conditions by microcalorimetry, chemical analyses of fermentation products and stable-isotope probing (SIP). The fermentation of (13) C-labeled glucose was monitored over 4 weeks by microcalorimetry in a stimulation experiment with tidal-flat sediments. Based on characteristic heat production phases, time points were selected for quantifying fermentation products and identifying substrate-assimilating bacteria by the isolation of intact ribosomes prior to rRNA-SIP. The preisolation of ribosomes resulted in rRNA with an excellent quality. Glucose was completely consumed within 2 days and was mainly fermented to acetate. Ethanol, formate, and hydrogen were detected intermittently. The amount of propionate that was built within the first 3 days stayed constant. Ribosome-based SIP of fully labeled and unlabeled rRNA was used for fingerprinting the glucose-degrading species and the inactive background community. The most abundant actively degrading bacterium was related to Psychromonas macrocephali (similarity 99%) as identified by DGGE and sequencing. The disappearance of Desulfovibrio-related bands in labeled rRNA after 3 days indicated that this group was active during the first degradation phase only. In summary, ribosome-based SIP in combination with microcalorimetry allows dissecting distinct phases in substrate turnover in a very sensitive manner.

  1. Combination of external loads

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S.; Tarp Johansen, N.J.; Joergensen, H. [Forskningscenter Risoe, Roskilde (Denmark); Gravesen, H.; Soerensen, S.L. [Carl Bro, Glostrup (Denmark); Pedersen, J. [Elsam Engineering, Fredericia (Denmark); Zorn, R.; Hvidberg Knudsen, M. [DHI Water and Environment, Hoersholm (Denmark); Voelund, P. [Energi E2, Koebenhavn (Denmark)

    2003-09-01

    The project onbectives have been: To improve and consequently opimise the basis for design of offshore wind turbines. This is done through 1) mapping the wind, wave ice and current as well as correlations of these, and 2) by clarifyring how these external conditions transform into loads. A comprehensive effort has been made to get a thorough understanding of the uncertainties that govern the reliability of wind turbines with respect to wind and wave loading. One of the conclusions is that the reliability of wind turbines is generally lower, than the average reliability of building structures that are subject not only to environmental loads, which are very uncertain, but also imposed loads and self weight, which are less uncertain than the environmental loads. The implication is that, at the moment lower load partial safety factors for onshore wind turbines cannot be recommended. For the combination of wind and wave design loads the problem is twofold: 1). A very conservative design will be generated by simply adding the individual wind and wave design loads disregarding the independence of the short-term fluctuations of wind and wave loads. 2). Characteristic values and partial safety factors for wind and wave loads are not defined similarly. This implies that the reliability levels of turbine support structures subject to purely aerodynamic loads and subject to purely hydrodynamic loads are not identical. For the problem of combining aerodynamic design loads and hydrodynamic design loads two results have been obtained in the project: 1). By simple means a site specific wave load safety factor rendering the same safety level for hydrodynamic loads as for aerodynamic loads is derived, and next, by direct square summation of extreme fluctuations, the wind and wave load safety factors are weighted. 2). Under the assumptions that a deep water site is considered and that the wave loading is a fifty-fifty mix of drag and inertia the same wind and wave load safety factor

  2. Biomass Gasification Combined Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Judith A. Kieffer

    2000-07-01

    Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

  3. Imidacloprid induces changes in the structure, genetic diversity and catabolic activity of soil microbial communities.

    Science.gov (United States)

    Cycoń, Mariusz; Markowicz, Anna; Borymski, Sławomir; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2013-12-15

    This is the first report describing the effect of imidacloprid applied at field rate (FR, 1 mg/kg of soil) and 10 times the FR (10*FR, 10 mg/kg of soil) on the structural, genetic and physiological diversity of soil bacterial community as determined by the phospholipid fatty acid (PLFA), the denaturing gradient gel electrophoresis (DGGE), and the community level physiological profile (CLPP) approaches. PLFA profiles showed that imidacloprid significantly shifted the microbial community structure and decreased the biomass of the total, bacterial and fungal PLFAs, however, this effect was transient at the FR dosage. The alterations in DGGE patterns caused by imidacloprid application, confirmed considerable changes in the overall richness and diversity of dominant bacteria. Although, as a result of imidacloprid application, the metabolic activity of microbial communities was generally lower, the richness and functional biodiversity of the soil microbial community were not negatively affected. In general, the analysis of the variance indicated that the measured parameters were significantly affected by treatment and the incubation time, however, the incubation time effect explained most of the observed variance. Imidacloprid degradation and the appearance of some new bands in DGGE profiles suggest the evolution of bacteria capable of degrading imidacloprid among indigenous microflora.

  4. Propagating Class and Method Combination

    DEFF Research Database (Denmark)

    Ernst, Erik

    1999-01-01

    This paper presents a mixin based class and method combination mechanism with block structure propagation. Traditionally, mixins can be composed to form new classes, possibly merging the implementations of methods (as in CLOS). In our approach, a class or method combination operation may cause any...... number of implicit combinations. For example, it is possible to specify separate aspects of a family of classes, and then combine several aspects into a full-fledged class family. The combination expressions would explicitly combine whole-family aspects, and by propagation implicitly combine the aspects...... for each member of the class family, and again by propagation implicitly compose each method from its aspects. As opposed to CLOS, this is type-checked statically; and as opposed to other systems for advanced class combination/ merging/weaving, it is integrated directly in the language, ensuring a clear...

  5. LIDAR COMBINED SCANNING UNIT

    Directory of Open Access Journals (Sweden)

    V. V. Elizarov

    2016-11-01

    Full Text Available Subject of Research. The results of lidar combined scanning unit development for locating leaks of hydrocarbons are presented The unit enables to perform high-speed scanning of the investigated space in wide and narrow angle fields. Method. Scanning in a wide angular field is produced by one-line scanning path by means of the movable aluminum mirror with a frequency of 20Hz and amplitude of 20 degrees of swing. Narrowband scanning is performed along a spiral path by the deflector. The deflection of the beam is done by rotation of the optical wedges forming part of the deflector at an angle of ±50. The control function of the scanning node is performed by a specialized software product written in C# programming language. Main Results. This scanning unit allows scanning the investigated area at a distance of 50-100 m with spatial resolution at the level of 3 cm. The positioning accuracy of the laser beam in space is 15'. The developed scanning unit gives the possibility to browse the entire investigated area for the time not more than 1 ms at a rotation frequency of each wedge from 50 to 200 Hz. The problem of unambiguous definition of the beam geographical coordinates in space is solved at the software level according to the rotation angles of the mirrors and optical wedges. Lidar system coordinates are determined by means of GPS. Practical Relevance. Development results open the possibility for increasing the spatial resolution of scanning systems of a wide range of lidars and can provide high positioning accuracy of the laser beam in space.

  6. Combination strategies for pain management.

    Science.gov (United States)

    Raffa, Robert B; Clark-Vetri, Rachel; Tallarida, Ronald J; Wertheimer, Albert I

    2003-10-01

    At least two factors relating to pain management using oral analgesics suggest that combination strategies merit consideration: many pains arise from more than one physiological cause and current analgesics have adverse effect profiles that might be reduced by combination with another agent in smaller doses or with less frequent dosing. In addition to increased convenience, combinations sometimes also result in the unexpected benefit of synergy. But not all pains, clinical settings or combinations merit the extra expense or other potential negative features of fixed-ratio products. This review examines the multiple basic science, clinical and pharmacoeconomic issues relating to analgesic combinations and the methodologies available for assessing these issues.

  7. Integrated coal gasification combined cycle

    Science.gov (United States)

    Richards, P. C.; Wijffels, J.-B.; Zuideveld, P. L.

    Features of the integrated coal gasification combined cycle power plants are described against the backdrop of the development and first commercial application of the shell coal gasification process. Focus is on the efficiency and excellent environmental performance of the integrated coal gasification combined power plants. Current IGCC projects are given together with an outline of some of the options for integrating coal gasification with combined cycles and also other applications of synthesis gas.

  8. Combined Environment Acoustic Chamber (CEAC)

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The CEAC imposes combined acoustic, thermal and mechanical loads on aerospace structures. The CEAC is employed to measure structural response and determine...

  9. Pseudomonas community structure and antagonistic potential in the rhizosphere : insights gained by combining phylogenetic and functional gene-based analyses

    NARCIS (Netherlands)

    Costa, Rodrigo; Gomes, Newton C. M.; Kroegerrecklenfort, Ellen; Opelt, Katja; Berg, Gabriele; Smalla, Kornelia

    2007-01-01

    The Pseudomonas community structure and antagonistic potential in the rhizospheres of strawberry and oilseed rape (host plants of the fungal phytopathogen Verticillium dahliae) were assessed. The use of a new PCR-DGGE system, designed to target Pseudomonas-specific gacA gene fragments in environment

  10. [Antilipemic agents in combined therapy].

    Science.gov (United States)

    Márk, László; Császár, Albert

    2002-08-25

    In the prevention of coronary heart disease the aim to achieve the target cholesterol and triglyceride levels and the maximal risk reduction leads to the combination of lipid lowering agents. The importance of the combination is supported by the fact that in monotherapy use of the high dose of the drugs, the lipid lowering effect is modest and the side effects are more frequent. The combined therapy is expected to be used more frequently despite the fact, that the improperly applied combination could have serious unfavourable effects. The authors review the advantages and drawbacks of the fibrate-statin combination, which could be used in the most frequent lipid abnormality, the high cholesterol and high triglyceride level, when the combination of micronized fenofibrate and fluvastatin is recommended. Beside the co-administration of other lipid lowering drugs (nicotine acid and resins), it is discussed the combination of statins and fibrates with a new, cholesterol absorption inhibitor, ezetimibe, a well tolerated drug with advantageous safety profile. Considering further metabolic risks the combination of lipid lowering drugs with glitazones, hormone replacement therapy, homocysteine reducing agents is as well highlighted.

  11. Revised Accounting for Business Combinations

    Science.gov (United States)

    Wilson, Arlette C.; Key, Kimberly

    2008-01-01

    The Financial Accounting Standards Board (FASB) has recently issued Statement of Financial Accounting Standards No. 141 (Revised 2007) Business Combinations. The object of this Statement is to improve the relevance, representational faithfulness, and comparability of reported information about a business combination and its effects. This Statement…

  12. Combination moisture and hydrogen getter

    Science.gov (United States)

    Harrah, L.A.; Mead, K.E.; Smith, H.M.

    1983-09-20

    A combination moisture and hydrogen getter comprises (a) a moisture getter comprising a readily oxidizable metal; and (b) a hydrogen getter comprising (1) a solid acetylenic compound and (2) a hydrogenation catalyst. A method of scavenging moisture from a closed container uses the combination moisture and hydrogen getter to irreversibly chemically reduce the moisture and chemically bind the resultant hydrogen.

  13. Oxycodone combinations for pain relief.

    Science.gov (United States)

    Raffa, R B; Pergolizzi, J V; Segarnick, D J; Tallarida, R J

    2010-06-01

    No single analgesic drug provides the perfect therapeutic/adverse effect profile for every pain condition. In addition to convenience and possibly improved compliance, a combination of analgesic drugs offers the potential, requiring verification, of providing greater pain relief and/or reduced adverse effects than the constituent drugs when used individually. We review here analgesic combinations containing oxycodone. We found surprisingly little preclinical information about the analgesic or adverse effect profiles of the combinations (with acetaminophen, paracetamol, nonsteroidal anti-inflammatory drugs, morphine, gabapentin or pregabalin). Clinical experience and studies suggest that the combinations are safe and effective and may offer certain advantages. As with all combinations, the profile of adverse effects must also be determined in order to provide the clinician with the overall benefit/risk assessment.

  14. Multidimensional Datawarehouse with Combination Formula

    CERN Document Server

    Warnars, Spits

    2010-01-01

    Multidimensional in data warehouse is a compulsion and become the most important for information delivery, without multidimensional Multidimensional in data warehouse is a compulsion and become the most important for information delivery, without multidimensional datawarehouse is incomplete. Multidimensional give ability to analyze business measurement in many different ways. Multidimensional is also synonymous with online analytical processing (OLAP). By using some concepts in datawarehouse like slice-dice,drill down and roll up will increase the ability of multidimensional datawarehouse. The research question and the discussing for this paper are how much deepest the multidimensional ability from each fact table in datawarehouse. By using the statistic combination formula we try to explore the combination that can be yielded from each dimension in hypercubes, the entire of dimensi combination, minimum combination and maximum combination.

  15. Microbial Biogeography along an Estuarine Salinity Gradient: Combined Influences of Bacterial Growth and Residence Time

    OpenAIRE

    Crump, Byron C.; Hopkinson, Charles S.; Sogin, Mitchell L.; Hobbie, John E

    2004-01-01

    Shifts in bacterioplankton community composition along the salinity gradient of the Parker River estuary and Plum Island Sound, in northeastern Massachusetts, were related to residence time and bacterial community doubling time in spring, summer, and fall seasons. Bacterial community composition was characterized with denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S ribosomal DNA. Average community doubling time was calculated from bacterial production ([14C]leucine incorpo...

  16. Combining norms to prove termination

    DEFF Research Database (Denmark)

    Genaim, S.; Codish, M.; Gallagher, John Patrick;

    2002-01-01

    of deriving automatically a candidate norm with which to prove termination. Instead of deriving a single, complex norm function, it is sufficient to determine a collection of simpler norms, some combination of which, leads to a proof of termination. We propose that a collection of simple norms, one for each...... of the recursive data-types in the program, is often a suitable choice. We first demonstrate the power of combining norm functions and then the adequacy of combining norms based on regular types....

  17. New combinations in African Sapindaceae

    DEFF Research Database (Denmark)

    Friis, Ib; Vollesen, Kaj; Verdcourt, Bernard

    1996-01-01

    Three new combinations are formally made: Allophylus rubifolius (A. Rich.) Engl. var. alnifolius (Baker) Friis & Vollesen, Allophylus rubifolius (A. Rich.) Engl. var. rhusiphyllus (Balf.f.) Froos & Vollesen and Haplocoelum folosum (Hiern) Bullock subsp. mombasense (Bullock) Verdc....

  18. The efficiency of combined machinings

    OpenAIRE

    2012-01-01

    This paper analyses the efficiency of the finish process applied in machining of hard surfaces, completed by grinding, hard turning and also by the combination of these two procedures, on the basis of time consumption.

  19. Autonomous grain combine control system

    Science.gov (United States)

    Hoskinson, Reed L.; Kenney, Kevin L.; Lucas, James R.; Prickel, Marvin A.

    2013-06-25

    A system for controlling a grain combine having a rotor/cylinder, a sieve, a fan, a concave, a feeder, a header, an engine, and a control system. The feeder of the grain combine is engaged and the header is lowered. A separator loss target, engine load target, and a sieve loss target are selected. Grain is harvested with the lowered header passing the grain through the engaged feeder. Separator loss, sieve loss, engine load and ground speed of the grain combine are continuously monitored during the harvesting. If the monitored separator loss exceeds the selected separator loss target, the speed of the rotor/cylinder, the concave setting, the engine load target, or a combination thereof is adjusted. If the monitored sieve loss exceeds the selected sieve loss target, the speed of the fan, the size of the sieve openings, or the engine load target is adjusted.

  20. Combined radar and telemetry system

    Energy Technology Data Exchange (ETDEWEB)

    Rodenbeck, Christopher T.; Young, Derek; Chou, Tina; Hsieh, Lung-Hwa; Conover, Kurt; Heintzleman, Richard

    2017-08-01

    A combined radar and telemetry system is described. The combined radar and telemetry system includes a processing unit that executes instructions, where the instructions define a radar waveform and a telemetry waveform. The processor outputs a digital baseband signal based upon the instructions, where the digital baseband signal is based upon the radar waveform and the telemetry waveform. A radar and telemetry circuit transmits, simultaneously, a radar signal and telemetry signal based upon the digital baseband signal.

  1. Combined cataract and strabismus surgery.

    Science.gov (United States)

    Gayton, J L; Ledford, J K

    1993-08-01

    A patient with cataracts and congenital exotropia underwent combined cataract and strabismus surgery OU. A lateral rectus recession plus an extracapsular cataract extraction with intraocular lens implantation was done OD first; three months later, this procedure was repeated OS. The patient's postoperative course was benign in both cases, and her strabismus resolved after the second operation. A combined surgical approach to cataracts and strabismus (where only a single muscle is involved) was safe and useful in restoring this patient's vision, binocularity, and appearance.

  2. COMBINED HEART-KIDNEY TRANSPLANTATION

    OpenAIRE

    V. N. Poptsov

    2016-01-01

    Combined heart-kidney transplantation may be performed in carefully selected patients with end-stage heart disease and renal failure. There are two types of combined transplantation of heart and kidney: 1) simultaneous heart-kidney transplantation (SHKT) from the same donor; 2) staged transplantation of heart and kidneys from two genetically different donors. The ISHLT registry in 2014 reported an increase in the number of SHKT over the years: from 22 in 1994 to 97 in 2012. World experience d...

  3. Intelligence Fusion for Combined Operations

    Science.gov (United States)

    1994-06-03

    doctrine on intelligence in combined operations, the lessons learned from the most recent combined operations, the current state of intelligence fision ...control of nuclear weapons and arms proliferation in the former Soviet Union.’ In Asia, the United States maintains a military presence in support of...emanating from other than nuclear or radioactive sources. Individual Reports Database - The portion of the LOCE database consisting of entity data records

  4. Combined sensor noise-immunity

    Institute of Scientific and Technical Information of China (English)

    Vladimir A. Shchurov; Alexander V. Shchurov

    2002-01-01

    The paper presents statistical analysis of combined sensor noise-immunity while recording fluctuating tone against underwater dynamic noise background. The experimental data used for the analysis have been collected by a pair of four-component combined sensors centered at two depths, 150 and 300 m in deep water. Expressions for combined sensor signalto-noise ratio (SNR) for cross-spectral levels of signal and noise for both wide and narrow frequency bands have been derived. A combined sensor gain has been introduced in terms of ordinary single-point coherence function between acoustic pressure and particle velocity in acoustic wave. The estimates obtained experimentally evidence that SNR for a combined sensor with multiplicative data processing may exceed SNR for a hydrophone-based sensor by 15 to 16 dB at most for the horizontal channel of the combined sensor, and by 30 dB at most for the vertical channel (when opposite energy flows of signal and noise compensate one another).

  5. COMBINE Archive Specification Version 1.

    Science.gov (United States)

    Bergmann, Frank T; Rodriguez, Nicolas; Le Novère, Nicolas

    2015-09-04

    Several standard formats have been proposed that can be used to describe models, simulations, data or other essential information in a consistent fashion. These constitute various separate components required to reproduce a given published scientific result. The Open Modeling EXchange format (OMEX) supports the exchange of all the information necessary for a modeling and simulation experiment in biology. An OMEX file is a ZIP container that includes a manifest file, an optional metadata file, and the files describing the model. The manifest is an XML file listing all files included in the archive and their type. The metadata file provides additional information about the archive and its content. Although any format can be used, we recommend an XML serialization of the Resource Description Framework. Together with the other standard formats from the Computational Modeling in Biology Network (COMBINE), OMEX is the basis of the COMBINE Archive. The content of a COMBINE Archive consists of files encoded in COMBINE standards whenever possible, but may include additional files defined by an Internet Media Type. The COMBINE Archive facilitates the reproduction of modeling and simulation experiments in biology by embedding all the relevant information in one file. Having all the information stored and exchanged at once also helps in building activity logs and audit trails.

  6. Combination trading with limit orders

    Directory of Open Access Journals (Sweden)

    Henry Schellhorn

    1997-01-01

    Full Text Available We model the exchange of commodities that are contingent upon each other, when traders place mostly limit orders. Examples include: 1 a market of financial futures where future spreads are also traded, 2 a market of mutual funds and stocks, 3 a market of options and stocks, under the viewpoint that they are both combinations of Arrow-Debreu securities. We prove that consistent prices are optimal. We develop a fixed-point algorithm to compute an optimal price and allocation. The algorithm combines ideas from contraction mapping theory and from homotopy theory. It is much faster than a traditional linear programming approach.

  7. SIMULATION OF THE COMBINED METHOD

    Directory of Open Access Journals (Sweden)

    Ilya Levin

    2011-10-01

    Full Text Available DDoS attacks have become one of the most dangerous issues in the Internet today. Because of theseattacks, legitimate users can not access the resources they need. In [1] authors proposeda combined method for tracing and blocking the sources of DDoS-attacks. The essence of the method isthat each router marks the network packet that passes through it using a random hash function from theset. At the receiving side this information is stored and used to filter unwanted traffic and traceback thesource of distributed attack. This article describes the simulation and its results of the combined method.

  8. Determining Covers in Combinational Circuits

    Directory of Open Access Journals (Sweden)

    Ljubomir Cvetkovic

    2011-05-01

    Full Text Available In this paper we propose a procedure for determining 0- or 1-cover of an arbitrary line in a combinational circuit. When determining a cover we do not need Boolean expression for the line; only the circuit structure is used. Within the proposed procedure we use the tools of the cube theory, in particular, some operations defined on cubes. The procedure can be applied for determining 0- and 1- covers of output lines in programmable logic devices. Basically, this procedure is a method for the analysis of a combinational circuit.

  9. H gas turbine combined cycle

    Energy Technology Data Exchange (ETDEWEB)

    Corman, J. [General Electric Co., Schenectady, NY (United States)

    1995-10-01

    A major step has been taken in the development of the Next Power Generation System - {open_quotes}H{close_quotes} Technology Combined Cycle. This new gas turbine combined-cycle system increases thermal performance to the 60% level by increasing gas turbine operating temperature to 1430 C (2600 F) at a pressure ratio of 23 to 1. Although this represents a significant increase in operating temperature for the gas turbine, the potential for single digit NOx levels (based upon 15% O{sub 2}, in the exhaust) has been retained. The combined effect of performance increase and environmental control is achieved by an innovative closed loop steam cooling system which tightly integrates the gas turbine and steam turbine cycles. The {open_quotes}H{close_quotes} Gas Turbine Combined Cycle System meets the goals and objectives of the DOE Advanced Turbine System Program. The development and demonstration of this new system is being carried out as part of the Industrial/Government cooperative agreement under the ATS Program. This program will achieve first commercial operation of this new system before the end of the century.

  10. Property Attribution in Combined Concepts

    Science.gov (United States)

    Spalding, Thomas L.; Gagné, Christina L.

    2015-01-01

    Recent research shows that the judged likelihood of properties of modified nouns ("baby ducks have webbed feet") is reduced relative to judgments for unmodified nouns ("ducks have webbed feet"). This modification effect has been taken as evidence both for and against the idea that combined concepts automatically inherit…

  11. Mode Combinations and International Operations

    DEFF Research Database (Denmark)

    Benito, Gabriel R. G.; Petersen, Bent; Welch, Lawrence S.

    2011-01-01

    reveals that companies tend to combine modes of operation; thereby producing unique foreign operation mode “packages” for given activities and/or countries, and that the packages are liable to be modified over time – providing a potentially important optional path for international expansion. Our data...

  12. Mode Combinations and International Operations

    DEFF Research Database (Denmark)

    Benito, Gabriel R. G.; Petersen, Bent; Welch, Lawrence S.

    2011-01-01

    reveals that companies tend to combine modes of operation; thereby producing unique foreign operation mode “packages” for given activities and/or countries, and that the packages are liable to be modified over time—providing a potentially important optional path for international expansion. The data show...

  13. A Radix-10 Combinational Multiplier

    DEFF Research Database (Denmark)

    Lang, Tomas; Nannarelli, Alberto

    2006-01-01

    reduces the number of partial product precomputations and uses counters to eliminate the need of the decimal equivalent of a 4:2 adder. The results of the implementation show that the combinational decimal multiplier offers a good compromise between latency and area when compared to other decimal multiply...

  14. Property Attribution in Combined Concepts

    Science.gov (United States)

    Spalding, Thomas L.; Gagné, Christina L.

    2015-01-01

    Recent research shows that the judged likelihood of properties of modified nouns ("baby ducks have webbed feet") is reduced relative to judgments for unmodified nouns ("ducks have webbed feet"). This modification effect has been taken as evidence both for and against the idea that combined concepts automatically inherit…

  15. Combined scleral buckling and phacoemulsification

    Directory of Open Access Journals (Sweden)

    Pukhraj Rishi

    2009-01-01

    Conclusion: Combined scleral buckling and phacoemulsification is a safe and effective procedure that spares the patient the burden of repeated surgeries. It may be considered as a treatment option in selected cases of rhegmatogenous retinal detachment with significant cataract with/without early PVR.

  16. Combination throttle and shutoff valve

    Science.gov (United States)

    Carriker, J. W.

    1972-01-01

    Combination of translating sleeve throttle valve and conventional poppet valve provides capability of shutting off flow completely by poppet and sleeve control of the rate of flow. Integration of the two concepts can be accomplished without difficulty and in a manner that requires a minimum of development.

  17. Diagnosis of severe combined immunodeficiency

    OpenAIRE

    Gennery, A; Cant, A

    2001-01-01

    Early diagnosis of severe combined immunodeficiency (SCID) is important to enable prompt referral to a supraregional centre for bone marrow transplantation before the occurrence of end organ damage secondary to infective complications. This review outlines clinical, microbiological, and immunopathological clues that aid the diagnosis of SCID and emphasises the multidisciplinary approach needed to diagnose and treat these infants.

  18. Airbreathing combined cycle engine systems

    Science.gov (United States)

    Rohde, John

    1992-01-01

    The Air Force and NASA share a common interest in developing advanced propulsion systems for commercial and military aerospace vehicles which require efficient acceleration and cruise operation in the Mach 4 to 6 flight regime. The principle engine of interest is the turboramjet; however, other combined cycles such as the turboscramjet, air turborocket, supercharged ejector ramjet, ejector ramjet, and air liquefaction based propulsion are also of interest. Over the past months careful planning and program implementation have resulted in a number of development efforts that will lead to a broad technology base for those combined cycle propulsion systems. Individual development programs are underway in thermal management, controls materials, endothermic hydrocarbon fuels, air intake systems, nozzle exhaust systems, gas turbines and ramjet ramburners.

  19. Pattern Recognition by Combined Invariants

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaohong; ZHAO Rongchun

    2001-01-01

    A feature-based recognition of objectsor patterns independent of their position, size, orien-tation and other variations has been the goal of muchrecent research. The existing approaches to invarianttwo-dimensional pattern recognition are useless whenpattern is blurred. In this paper, we present a novelpattern recognition system which can solve the prob-lem by using combined invariants as image features.The classification technique we choose for our systemis weighted normalized cross correlation. The mean ofthe intraclass standard deviations of the kth featureover the total number of prototypes for each class isused as a weighting factor during the classification pro-cess to improve recognition accuracy. The feasibilityof our pattern recognition system and the invarianceof the combined features with respect to translation,scaling, rotation and blurring are approved by numer-ical experiments on head images.

  20. Combined fertility and embryotoxicity study.

    Science.gov (United States)

    Reynaud, Lucie; Marsden, Edward

    2013-01-01

    Under normal circumstances, fertility and embryotoxicity studies are run separately according to the ICH S5(R2) guideline for the detection of toxicity to reproduction of medicinal products (1). However, the flexible approach of the S5(R2) guideline also allows the reproduction stages covered in the fertility and embryo-fetal development studies (stages A to D) to be combined into a single study design. The administration period covers the pre-mating and gestation phases through to closure of the hard palate. The principal advantages of the combined study include reductions in the number of animals required and cost. Although the rat is the routine species of choice, the mouse may also be used.

  1. Run 1 Higgs legacy combination

    CERN Document Server

    Donato, Silvio

    2016-01-01

    The total Higgs boson cross-section has been measured to be $1.09 \\pm 0.11$ the Standard Model prediction. The combination of the ATLAS and CMS results gives observed significances for the vector boson fusion production process and for the $H\\rightarrow \\tau \\tau$~decay of~$5.4$ and $5.5$~standard deviations, respectively. The data are consistent with the Standa...

  2. Combining different types of classifiers

    OpenAIRE

    Gatnar, Eugeniusz

    2008-01-01

    Model fusion has proved to be a very successful strategy for obtaining accurate models in classification and regression. The key issue, however, is the diversity of the component classifiers because classification error of an ensemble depends on the correlation between its members. The majority of existing ensemble methods combine the same type of models, e.g. trees. In order to promote the diversity of the ensemble members, we propose to aggregate classifiers of different t...

  3. Combining activity and economic efficiency

    DEFF Research Database (Denmark)

    Fersch, Barbara

    In the Danish welfare state, long-term care is a universal service that is run by the municipalities. The municipalities, although bound by a national legal framework, do have considerable autonomy concerning the concrete definition and organization of long-term care services. One of the newest “....... The paper provides a discourse analysis of the interviewees’ accounts, that shows how discourses on activity and economic efficiency have been combined in the Danish context....

  4. Radiosensitive Severe Combined Immunodeficiency Disease

    OpenAIRE

    Dvorak, Christopher C.; Cowan, Morton J.

    2010-01-01

    Inherited defects in components of the non-homologous end joining DNA repair mechanism produce a T-B-NK+ severe combined immunodeficiency disease (SCID) characterized by heightened sensitivity to ionizing radiation. Patients with the radiosensitive form of SCID may also have increased short- and long-term sensitivity to the alkylator-based chemotherapy regimens traditionally utilized for conditioning prior to allogeneic hematopoietic cell transplantation (HCT). Known etiologies of radiosensit...

  5. Combination chemoprevention with grape antioxidants.

    Science.gov (United States)

    Singh, Chandra K; Siddiqui, Imtiaz A; El-Abd, Sabah; Mukhtar, Hasan; Ahmad, Nihal

    2016-06-01

    Antioxidant ingredients present in grape have been extensively investigated for their cancer chemopreventive effects. However, much of the work has been done on individual ingredients, especially focusing on resveratrol and quercetin. Phytochemically, whole grape represents a combination of numerous phytonutrients. Limited research has been done on the possible synergistic/additive/antagonistic interactions among the grape constituents. Among these phytochemical constituents of grapes, resveratrol, quercetin, kaempferol, catechin, epicatechin, and anthocyanins (cyanidin and malvidin) constitute more than 70% of the grape polyphenols. Therefore, these have been relatively well studied for their chemopreventive effects against a variety of cancers. While a wealth of information is available individually on cancer chemopreventive/anti-proliferative effects of resveratrol and quercetin, limited information is available regarding the other major constituents of grape. Studies have also suggested that multiple grape antioxidants, when used in combination, alone or with other agents/drugs show synergistic or additive anti-proliferative response. Based on strong rationale emanating from published studies, it seems probable that a combination of multiple grape ingredients alone or together with other agents could impart 'additive synergism' against cancer. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Imagining a Stata / Python Combination

    Science.gov (United States)

    Fiedler, James

    2012-01-01

    There are occasions when a task is difficult in Stata, but fairly easy in a more general programming language. Python is a popular language for a range of uses. It is easy to use, has many high ]quality packages, and programs can be written relatively quickly. Is there any advantage in combining Stata and Python within a single interface? Stata already offers support for user-written programs, which allow extensive control over calculations, but somewhat less control over graphics. Also, except for specifying output, the user has minimal programmatic control over the user interface. Python can be used in a way that allows more control over the interface and graphics, and in so doing provide a roundabout method for satisfying some user requests (e.g., transparency levels in graphics and the ability to clear the results window). My talk will explore these ideas, present a possible method for combining Stata and Python, and give examples to demonstrate how this combination might be useful.

  7. A PCR-denaturing gradient gel electrophoresis (DGGE) approach to assess Fusarium diversity in asparagus

    NARCIS (Netherlands)

    Yergeau, E.; Filion, M.; Vujanovic, V.; St-Arnaud, M.

    2005-01-01

    In North America, asparagus (Asparagus officinalis) production suffers from a crown and root rot disease mainly caused by Fusarium oxysporum f. sp. asparagi and F. proliferatum. Many other Fusarium species are also found in asparagus fields, whereas accurate detection and identification of these org

  8. A PCR-denaturing gradient gel electrophoresis (DGGE) approach to assess Fusarium diversity in asparagus

    NARCIS (Netherlands)

    Yergeau, E.; Filion, M.; Vujanovic, V.; St-Arnaud, M.

    2005-01-01

    In North America, asparagus (Asparagus officinalis) production suffers from a crown and root rot disease mainly caused by Fusarium oxysporum f. sp. asparagi and F. proliferatum. Many other Fusarium species are also found in asparagus fields, whereas accurate detection and identification of these

  9. Combining Alphas via Bounded Regression

    Directory of Open Access Journals (Sweden)

    Zura Kakushadze

    2015-11-01

    Full Text Available We give an explicit algorithm and source code for combining alpha streams via bounded regression. In practical applications, typically, there is insufficient history to compute a sample covariance matrix (SCM for a large number of alphas. To compute alpha allocation weights, one then resorts to (weighted regression over SCM principal components. Regression often produces alpha weights with insufficient diversification and/or skewed distribution against, e.g., turnover. This can be rectified by imposing bounds on alpha weights within the regression procedure. Bounded regression can also be applied to stock and other asset portfolio construction. We discuss illustrative examples.

  10. [Combination chemotherapy of experimental leukemia].

    Science.gov (United States)

    Emanuel', N M; Konovalova, N P; D'iachkovskaia, R F

    1977-01-01

    In the present work an attempt was made to gain greater therapeutic effect of diazane coupled with adriamycin and sarcolysin. Leucemias L-1210 and La served as a model. In leucosis La diazane was injected once in 5 days. Either an additional injection of adriamycin two days prior to diazane injection or sarcolysin injected simultaneously with diazane enabled the authors to obtain a distinct synergestic effect. In leucemia L-1210 a simultaneous administration of diazane and sarcolysin also contributes to considerably longer survival of leucemic animals. Such combinations are likely to be promising in their clinical use.

  11. 16种EPA-PAHs复合污染土壤的菌群修复%Bioremediation of 16 EPA-PAHs combined contaminated-soil with microbial consortium

    Institute of Scientific and Technical Information of China (English)

    李政; 赵朝成; 张云波; 赵东风

    2012-01-01

    通过富集筛选获得一组PAHs降解混合菌群和3株降解单菌,利用变性梯度凝胶电泳(DGGE)技术分析混合菌群的组成,对16种多环芳烃(PAHs)复合污染土壤进行生物修复,同时考察混合菌群和单菌株在PAHs复合污染土壤中的生物修复效果.结果表明:混合菌群主要由3株已分离获得的降解单菌和5株未可分离培养的单菌组成;经过30 d的生物修复,混合菌群对土壤中总PAHs的降解率(54.17%)高于单一菌株(28.40%,31.95%,24.64%),并且对高相对分子质量PAHs的降解表现出了较大的优势,4环、5环、6环PAHs的降解率分别可达到71.26%、39.76%和42.86%;利用混合菌群来修复16种PAHs复合污染的土壤,可以避免一些未可分离培养的关键菌株的丢失,使PAHs的降解更加全面有效.%For bioremediation of polycyclic aromatic hydrocarbons ( PAHs) combined contaminated-soil, a microbial consortium and three strains were isolated from PAHs contaminated-soil containing sixteen US Environmental Protection Agency priority control PAHs. Denaturing gradient gel electrophoresis (DGGE) was used to analyze the structure of the microbial consortium , and the biodegradation effect of PAHs mixtures with the inoculation of mixed microbial consortium and single strain was studied. The results show that the consortium is mainly composed of three isolated strains and five uncultured bacterias. After 30 days bioremediation, the degradation efficiency of total PAHs by microbial consortium (54. 17% ) is higher than any single strain's (28. 40% ,31. 95% ,24. 64% ). Microbial consortium shows a great advantage in degradation of high relative molecular mass PAHs, and the degradation efficiencies of four-rings, five-rings and six-rings PAHs are 71. 26% , 39. 76% , 42. 86% , respectively. Microbial consortium is capable of degrading PAHs which can avoid the loss of key strains and has a good application prospect in the bioremediation of PAHs

  12. Radiation tolerant combinational logic cell

    Science.gov (United States)

    Maki, Gary R. (Inventor); Gambles, Jody W. (Inventor); Whitaker, Sterling (Inventor)

    2009-01-01

    A system has a reduced sensitivity to Single Event Upset and/or Single Event Transient(s) compared to traditional logic devices. In a particular embodiment, the system includes an input, a logic block, a bias stage, a state machine, and an output. The logic block is coupled to the input. The logic block is for implementing a logic function, receiving a data set via the input, and generating a result f by applying the data set to the logic function. The bias stage is coupled to the logic block. The bias stage is for receiving the result from the logic block and presenting it to the state machine. The state machine is coupled to the bias stage. The state machine is for receiving, via the bias stage, the result generated by the logic block. The state machine is configured to retain a state value for the system. The state value is typically based on the result generated by the logic block. The output is coupled to the state machine. The output is for providing the value stored by the state machine. Some embodiments of the invention produce dual rail outputs Q and Q'. The logic block typically contains combinational logic and is similar, in size and transistor configuration, to a conventional CMOS combinational logic design. However, only a very small portion of the circuits of these embodiments, is sensitive to Single Event Upset and/or Single Event Transients.

  13. Combination therapies in iron chelation

    Directory of Open Access Journals (Sweden)

    Raffaella Origa

    2014-12-01

    Full Text Available The availability of oral iron chelators and new non-invasive methods for early detection and treatment of iron overload, have significantly improved the life expectancy and quality of life of patients with b thalassemia major. However, monotherapy is not effective in all patients for a variety of reasons. We analyzed the most relevant reports recently published on alternating or combined chelation therapies in thalassemia major with special attention to safety aspects and to their effects in terms of reduction of iron overload in different organs, improvement of complications, and survival. When adverse effects, such as gastrointestinal upset with deferasirox or infusional site reactions with deferoxamine are not tolerable and organ iron is in an acceptable range, alternating use of two chelators (drugs taken sequentially on different days, but not taken on the same day together may be a winning choice. The association deferiprone and deferoxamine should be the first choice in case of heart failure and when dangerously high levels of cardiac iron exist. Further research regarding the safety and efficacy of the most appealing combination treatment, deferiprone and deferasirox, is needed before recommendations for routine clinical practice can be made.

  14. Performance of lazy combinator graph reduction

    NARCIS (Netherlands)

    Hartel, Pieter H.; Hartel, P.H.

    The performance of program-derived combinator graph reduction is known to be superior to that of graph reduction based on a fixed set of standard combinators. The major advantage of program-derived combinator reduction is that it uses less transient store than standard combinator reduction. We show

  15. Beam combination modes of the VLT

    Science.gov (United States)

    Merkle, Fritz

    The optical configuration of the ESO Very Large Telescope (VLT) is based on a linear array of 4 independently mounted 8-m telescopes. This concept allows a flexible and versatile use of the telescopes. They can be operated either independently or in various combination schemes. In the latter case, the light collected with the unit telescopes is fed via beam combination optics to the combined focus. The incoherent combination with a combined coude focus offers the light collecting power approximately equivalent to a 16-m single dish telescope. The efficiency of the combined foci operation is only given if the losses in the combining train are minimized.

  16. Combined processing of lead concentrates

    Science.gov (United States)

    Kubasov, V. L.; Paretskii, V. M.; Sidorin, G. N.; Travkin, V. F.

    2013-06-01

    A combined scheme of processing of lead concentrates with the production of pure metallic lead and the important components containing in these concentrates is considered. This scheme includes sulfating roasting of the lead concentrates and two-stage leaching of the formed cinder with the formation of a sulfate solution and lead sulfate. When transformed into a carbonate form, lead sulfate is used for the production of pure metallic lead. Silver, indium, copper, cadmium, nickel, cobalt, and other important components are separately extracted from a solution. At the last stage, zinc is extracted by either extraction followed by electrolytic extraction of a metal or the return of the forming solution of sulfuric acid to cinder leaching.

  17. Combined photoacoustic and ultrasound biomicroscopy.

    Science.gov (United States)

    Harrison, Tyler; Ranasinghesagara, Janaka C; Lu, Huihong; Mathewson, Kory; Walsh, Andrew; Zemp, Roger J

    2009-11-23

    We report on the development of an imaging system capable of combined ultrasound and photoacoustic imaging based on a fast-scanning single-element 25-MHz ultrasound transducer and a unique light-delivery system. The system is capable of 20 ultrasound frames per second and slower photoacoustic frame rates limited by laser pulse-repetition rates. Laser and ultrasound pulses are interlaced for co-registration of photoacoustic and ultrasound images. In vivo imaging of a human finger permits ultrasonic visualization of vessel structures and speckle changes indicative of blood flow, while overlaid photoacoustic images highlight some small vessels that are not clear from the ultrasound scan. Photoacoustic images provide optical absorption contrast co-registered in the structural and blood-flow context of ultrasound with high-spatial resolution and may prove important for clinical diagnostics and basic science of the microvasculature.

  18. Chemical and natural stressors combined:

    DEFF Research Database (Denmark)

    Gergs, André; Zenker, Armin; Grimm, Volker

    2013-01-01

    In addition to natural stressors, populations are increasingly exposed to chemical pollutants released into the environment. We experimentally demonstrate the loss of resilience for Daphnia magna populations that are exposed to a combination of natural and chemical stressors even though effects...... on population size of a single stressor were cryptic, i.e. hard to detect statistically. Data on Daphnia population demography and along with model-based exploration of our predator-prey system revealed that direct trophic interactions changed the population size-structure and thereby increased population...... vulnerability to the toxicant which acts in a size selective manner. Moreover, population vulnerability to the toxicant increases with predator size and predation intensity whereas indirect trait-mediated interactions via predator kairomones may buffer chemical effects to a certain extent. Our study...

  19. How rats combine temporal cues.

    Science.gov (United States)

    Guilhardi, Paulo; Keen, Richard; MacInnis, Mika L M; Church, Russell M

    2005-05-31

    The procedures for classical and operant conditioning, and for many timing procedures, involve the delivery of reinforcers that may be related to the time of previous reinforcers and responses, and to the time of onsets and terminations of stimuli. The behavior resulting from such procedures can be described as bouts of responding that occur in some pattern at some rate. A packet theory of timing and conditioning is described that accounts for such behavior under a wide range of procedures. Applications include the food searching by rats in Skinner boxes under conditions of fixed and random reinforcement, brief and sustained stimuli, and several response-food contingencies. The approach is used to describe how multiple cues from reinforcers and stimuli combine to determine the rate and pattern of response bouts.

  20. Combining supramolecular chemistry with biology.

    Science.gov (United States)

    Uhlenheuer, Dana A; Petkau, Katja; Brunsveld, Luc

    2010-08-01

    Supramolecular chemistry has primarily found its inspiration in biological molecules, such as proteins and lipids, and their interactions. Currently the supramolecular assembly of designed compounds can be controlled to great extent. This provides the opportunity to combine these synthetic supramolecular elements with biomolecules for the study of biological phenomena. This tutorial review focuses on the possibilities of the marriage of synthetic supramolecular architectures and biological systems. It highlights that synthetic supramolecular elements are for example ideal platforms for the recognition and modulation of proteins and cells. The unique features of synthetic supramolecular systems with control over size, shape, valency, and interaction strength allow the generation of structures fitting the demands to approach the biological problems at hand. Supramolecular chemistry has come full circle, studying the biology and its molecules which initially inspired its conception.

  1. Combined PET/MRI scanner

    Science.gov (United States)

    Schlyer, David; Woody, Craig L.; Rooney, William; Vaska, Paul; Stoll, Sean; Pratte, Jean-Francois; O'Connor, Paul

    2007-10-23

    A combined PET/MRI scanner generally includes a magnet for producing a magnetic field suitable for magnetic resonance imaging, a radiofrequency (RF) coil disposed within the magnetic field produced by the magnet and a ring tomograph disposed within the magnetic field produced by the magnet. The ring tomograph includes a scintillator layer for outputting at least one photon in response to an annihilation event, a detection array coupled to the scintillator layer for detecting the at least one photon outputted by the scintillator layer and for outputting a detection signal in response to the detected photon and a front-end electronic array coupled to the detection array for receiving the detection signal, wherein the front-end array has a preamplifier and a shaper network for conditioning the detection signal.

  2. Combined Shape and Topology Optimization

    DEFF Research Database (Denmark)

    Christiansen, Asger Nyman

    Shape and topology optimization seeks to compute the optimal shape and topology of a structure such that one or more properties, for example stiffness, balance or volume, are improved. The goal of the thesis is to develop a method for shape and topology optimization which uses the Deformable...... Simplicial Complex (DSC) method. Consequently, we present a novel method which combines current shape and topology optimization methods. This method represents the surface of the structure explicitly and discretizes the structure into non-overlapping elements, i.e. a simplicial complex. An explicit surface...... representation usually limits the optimization to minor shape changes. However, the DSC method uses a single explicit representation and still allows for large shape and topology changes. It does so by constantly applying a set of mesh operations during deformations of the structure. Using an explicit instead...

  3. Food combinations for cholesterol lowering.

    Science.gov (United States)

    Harland, Janice I

    2012-12-01

    Reducing elevated LDL-cholesterol is a key public health challenge. There is substantial evidence from randomised controlled trials (RCT) that a number of foods and food components can significantly reduce LDL-cholesterol. Data from RCT have been reviewed to determine whether effects are additive when two or more of these components are consumed together. Typically components, such as plant stanols and sterols, soya protein, β-glucans and tree nuts, when consumed individually at their target rate, reduce LDL-cholesterol by 3-9 %. Improved dietary fat quality, achieved by replacing SFA with unsaturated fat, reduces LDL-cholesterol and can increase HDL-cholesterol, further improving blood lipid profile. It appears that the effect of combining these interventions is largely additive; however, compliance with multiple changes may reduce over time. Food combinations used in ten 'portfolio diet' studies have been reviewed. In clinical efficacy studies of about 1 month where all foods were provided, LDL-cholesterol is reduced by 22-30 %, whereas in community-based studies of >6 months' duration, where dietary advice is the basis of the intervention, reduction in LDL-cholesterol is about 15 %. Inclusion of MUFA into 'portfolio diets' increases HDL-cholesterol, in addition to LDL-cholesterol effects. Compliance with some of these dietary changes can be achieved more easily compared with others. By careful food component selection, appropriate to the individual, the effect of including only two components in the diet with good compliance could be a sustainable 10 % reduction in LDL-cholesterol; this is sufficient to make a substantial impact on cholesterol management and reduce the need for pharmaceutical intervention.

  4. Coaxial combination of coherent laser beams

    Institute of Scientific and Technical Information of China (English)

    Hongcheng Dong; Xiao Li; Chaoyang Wei; Hongbo He; Yuanan Zhao; Jianda Shao; Zhengxiu Fan

    2009-01-01

    @@ Based on polarization state conversion, a technique for coaxially coherent combination of laser beams is introduced.Laser beams can be coaxially coupled into one beam with high combination efficiency and perfect beam quality.A polarized laser beam combination system based on master oscillator power amplifier (MOPA) configuration is developed and the efficiencies of both unit combination and the whole system are investigated.In the experiment of combining four beams with single longitudinal mode, a combination efficiency of 85.3% is achieved.It can be further enhanced by improving the stability of experimental environment and the quality of optical and mechanical components.

  5. Combined Reduced-Rank Transform

    Directory of Open Access Journals (Sweden)

    Anatoli Torokhti

    2006-04-01

    Full Text Available We propose and justify a new approach to constructing optimal nonlinear transforms of random vectors. We show that the proposed transform improves such characteristics of {rank-reduced} transforms as compression ratio, accuracy of decompression and reduces required computational work. The proposed transform ${mathcal T}_p$ is presented in the form of a sum with $p$ terms where each term is interpreted as a particular rank-reduced transform. Moreover, terms in ${mathcal T}_p$ are represented as a combination of three operations ${mathcal F}_k$, ${mathcal Q}_k$ and ${oldsymbol{varphi}}_k$ with $k=1,ldots,p$. The prime idea is to determine ${mathcal F}_k$ separately, for each $k=1,ldots,p$, from an associated rank-constrained minimization problem similar to that used in the Karhunen--Lo`{e}ve transform. The operations ${mathcal Q}_k$ and ${oldsymbol{varphi}}_k$ are auxiliary for f/inding ${mathcal F}_k$. The contribution of each term in ${mathcal T}_p$ improves the entire transform performance. A corresponding unconstrained nonlinear optimal transform is also considered. Such a transform is important in its own right because it is treated as an optimal filter without signal compression. A rigorous analysis of errors associated with the proposed transforms is given.

  6. Isolated and Combined Remethylation Disorders

    Directory of Open Access Journals (Sweden)

    Eva Richard PhD

    2017-01-01

    Full Text Available Genetic defects affecting the remethylation pathway cause hyperhomocysteinemia. Isolated remethylation defects are caused by mutations of the 5, 10-methylenetetrahydrofolate reductase (MTHFR, methionine synthase reductase (MTRR, methionine synthase (MTR, and MMADHC genes, and combined remethylation defects are the result of mutations in genes involved in the synthesis of either methylcobalamin or adenosylcobalamin, that is, the active cofactors of MTRR and methylmalonyl-CoA mutase. Diagnosis is based on the biochemical analysis of amino acids, homocysteine, propionylcarnitine, methylmalonic acid, S-adenosylmethionine, and 5-methylentetrahydrofolate in physiological fluids. Gene-by-gene Sanger sequencing has long been the gold standard genetic analysis for confirming the disorder and identifying the gene involved, but massive parallel sequencing is now being used to examine all those potentially involved in one go. Early treatment to rescue metabolic homeostasis is based on the following of an appropriate diet, betaine administration, and, in some cases, oral or intramuscular administration of vitamin B12 or folate. Elevated ROS levels, apoptosis, endoplasmic reticulum (ER stress, the activation of autophagy, and alterations in Ca2+ homeostasis may all contribute toward the pathogenesis of the disease. Pharmacological agents to restore the function of the ER and mitochondria and/or to reduce oxidative stress-induced apoptosis might provide novel ways of treating patients with remethylation disorders.

  7. Isolated and Combined Remethylation Disorders

    Directory of Open Access Journals (Sweden)

    Eva Richard PhD

    2017-01-01

    Full Text Available Genetic defects affecting the remethylation pathway cause hyperhomocysteinemia. Isolated remethylation defects are caused by mutations of the 5, 10-methylenetetrahydrofolate reductase (MTHFR , methionine synthase reductase (MTRR , methionine synthase (MTR , and MMADHC genes, and combined remethylation defects are the result of mutations in genes involved in the synthesis of either methylcobalamin or adenosylcobalamin, that is, the active cofactors of MTRR and methylmalonyl-CoA mutase. Diagnosis is based on the biochemical analysis of amino acids, homocysteine, propionylcarnitine, methylmalonic acid, S-adenosylmethionine, and 5-methylentetrahydrofolate in physiological fluids. Gene-by-gene Sanger sequencing has long been the gold standard genetic analysis for confirming the disorder and identifying the gene involved, but massive parallel sequencing is now being used to examine all those potentially involved in one go. Early treatment to rescue metabolic homeostasis is based on the following of an appropriate diet, betaine administration, and, in some cases, oral or intramuscular administration of vitamin B 12 or folate. Elevated ROS levels, apoptosis, endoplasmic reticulum (ER stress, the activation of autophagy, and alterations in Ca 2+ homeostasis may all contribute toward the pathogenesis of the disease. Pharmacological agents to restore the function of the ER and mitochondria and/or to reduce oxidative stress-induced apoptosis might provide novel ways of treating patients with remethylation disorders.

  8. Radiosensitive Severe Combined Immunodeficiency Disease

    Science.gov (United States)

    Dvorak, Christopher C.; Cowan, Morton J.

    2009-01-01

    Synopsis Inherited defects in components of the non-homologous end joining DNA repair mechanism produce a T-B-NK+ severe combined immunodeficiency disease (SCID) characterized by heightened sensitivity to ionizing radiation. Patients with the radiosensitive form of SCID may also have increased short- and long-term sensitivity to the alkylator-based chemotherapy regimens traditionally utilized for conditioning prior to allogeneic hematopoietic cell transplantation (HCT). Known etiologies of radiosensitive SCID include deficiencies of Artemis, DNA Ligase IV, DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and Cernunnos-XLF, all of which have been treated with HCT. Because of their sensitivity to certain forms of chemotherapy, the approach to donor selection and type of conditioning regimen utilized for a radiosensitive SCID patient requires careful consideration. Significantly more research needs to be done in order to determine the long-term outcomes of radiosensitive SCID patients following HCT, as well as to discover novel non-toxic approaches to HCT that might benefit those with intrinsic radio- and chemo-sensitivity, as well as potentially all patients undergoing an HCT. PMID:20113890

  9. Improving Writing with Sentence Combining Exercises.

    Science.gov (United States)

    Nutter, Norma; Safran, Joan

    1984-01-01

    Sentence-combining exercises, which require students to combine simple sentences in any way they wish, have helped learning disabled elementary children improve skills in writing, reading, and spelling. The exercises are flexible, motivating, and simple to design. (CL)

  10. New taxa and combinations in Rutaceae

    NARCIS (Netherlands)

    Kaastra, R.C.

    1977-01-01

    New taxa and combinations are published here in anticipation of the revision of the Rutaceae-Pilocarpinae to be published in the near future (thesis, and in Flora Neotropica). Two new combinations of species excluded from subtribe Pilocarpinae are added.

  11. Combining multiple classifiers for age classification

    CSIR Research Space (South Africa)

    Van Heerden, C

    2009-11-01

    Full Text Available The authors compare several different classifier combination methods on a single task, namely speaker age classification. This task is well suited to combination strategies, since significantly different feature classes are employed. Support vector...

  12. Locations of Combined Sewer Overflow Outfalls

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer identifies the locations of Combined sewer overflow outfalls. Combined sewer systems are sewers that are designed to collect rainwater runoff,...

  13. Efficient Web Services Policy Combination

    Science.gov (United States)

    Vatan, Farrokh; Harman, Joseph G.

    2010-01-01

    Large-scale Web security systems usually involve cooperation between domains with non-identical policies. The network management and Web communication software used by the different organizations presents a stumbling block. Many of the tools used by the various divisions do not have the ability to communicate network management data with each other. At best, this means that manual human intervention into the communication protocols used at various network routers and endpoints is required. Developing practical, sound, and automated ways to compose policies to bridge these differences is a long-standing problem. One of the key subtleties is the need to deal with inconsistencies and defaults where one organization proposes a rule on a particular feature, and another has a different rule or expresses no rule. A general approach is to assign priorities to rules and observe the rules with the highest priorities when there are conflicts. The present methods have inherent inefficiency, which heavily restrict their practical applications. A new, efficient algorithm combines policies utilized for Web services. The method is based on an algorithm that allows an automatic and scalable composition of security policies between multiple organizations. It is based on defeasible policy composition, a promising approach for finding conflicts and resolving priorities between rules. In the general case, policy negotiation is an intractable problem. A promising method, suggested in the literature, is when policies are represented in defeasible logic, and composition is based on rules for non-monotonic inference. In this system, policy writers construct metapolicies describing both the policy that they wish to enforce and annotations describing their composition preferences. These annotations can indicate whether certain policy assertions are required by the policy writer or, if not, under what circumstances the policy writer is willing to compromise and allow other assertions to take

  14. Combining fluorescence and bioluminescence microscopy.

    Science.gov (United States)

    Goda, Kazuhito; Hatta-Ohashi, Yoko; Akiyoshi, Ryutaro; Sugiyama, Takashi; Sakai, Ikuko; Takahashi, Takeo; Suzuki, Hirobumi

    2015-08-01

    Bioluminescence microscopy has revealed that gene expression in individual cells can respond differently to the same stimulus. To understand this phenomenon, it is important to sequentially observe the series of events from cellular signal transduction to gene expression regulated by specific transcription factors derived from signaling cascades in individual cells. However, these processes have been separately analyzed with fluorescence and bioluminescence microscopy. Furthermore, in culture medium, the background fluorescence of luciferin-a substrate of luciferase in promoter assays of gene expression in cultured cells-confounds the simultaneous observation of fluorescence and bioluminescence. Therefore, we optimized conditions for optical filter sets based on spectral properties and the luciferin concentration based on cell permeability for fluorescence observation combined with bioluminescence microscopy. An excitation and emission filter set (492-506 nm and 524-578 nm) was suitable for green fluorescent protein and yellow fluorescent protein imaging of cells, and >100 μM luciferin was acceptable in culture medium based on kinetic constants and the estimated intracellular concentration. Using these parameters, we present an example of sequential fluorescence and bioluminescence microscopic observation of signal transduction (translocation of protein kinase C alpha from the cytoplasm to the plasma membrane) coupled with activation of gene expression by nuclear factor of kappa light polypeptide B in individual cells and show that the gene expression response is not completely concordant with upstream signaling following stimulation with phorbol-12-myristate-13-acetate. Our technique is a powerful imaging tool for analysis of heterogeneous gene expression together with upstream signaling in live single cells.

  15. An Action Analysis for Combining Partial Evaluation

    Institute of Scientific and Technical Information of China (English)

    廖湖声

    2000-01-01

    This paper proposes an action analysis for implementing combining partial evaluation efficiently. By analyzing the results of binding time analysis, operations, which should be used in the combining partial evaluation, are determined in advance, so that the computation in the combination of specialized programs is reduced effectively.

  16. Statistical combination of experimental results in ATLAS

    CERN Document Server

    Gadatsch, Stefan; The ATLAS collaboration

    2016-01-01

    The combination of experimental results requires a careful statistical treatment. We review the methods and tools used in ATLAS for the statistical combination of measurements and of limits on new physics. We highlight the methods used in the recent combination of ATLAS and CMS measurements of the Higgs boson production/decay rates and the constraints on the Higgs coupling parameters.

  17. 7 CFR 4280.193 - Combined funding.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Combined funding. 4280.193 Section 4280.193... Efficiency Improvements Program Section D. Combined Funding § 4280.193 Combined funding. The requirements for... if the project meets the requirements specified in § 4280.109. (b) Funding. Funding provided...

  18. 49 CFR 387.305 - Combination vehicles.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Combination vehicles. 387.305 Section 387.305 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... § 387.305 Combination vehicles. The following combinations will be regarded as one motor vehicle...

  19. Systemic combination treatment for psoriasis: a review

    DEFF Research Database (Denmark)

    Jensen, Peter; Skov, Lone; Zachariae, Claus

    2010-01-01

    exist for the use of systemic combination therapy. Therefore, our aim was to review the current literature on systemic anti-psoriatic combination regimens. We searched PubMed and identified 98 papers describing 116 studies (23 randomized) reporting on the effect of various systemic combination...

  20. Firey linear combinations of convex bodies

    Institute of Scientific and Technical Information of China (English)

    XIONG Ge; XIAO Qi-ming; CHEUNG Wing-Sum

    2009-01-01

    For convex bodies, the Firey linear combinations were introduced and studied in several papers. In this paper the mean width of the Firey linear combinations of convex bodies is studied, and the lower bound of the mean width of the Firey linear combinations of convex body and its polar body is given.

  1. Identification, isolation and quantification of representative bacteria from fermented cassava dough using an integrated approach of culture-dependent and culture-independent methods.

    Science.gov (United States)

    Miambi, Edouard; Guyot, Jean-Pierre; Ampe, Frédéric

    2003-04-25

    The use of denaturing gradient gel electrophoresis (DGGE) and traditional culture-depending methods for examining the bacterial community of traditional cassava starch fermentation were investigated. It appeared that DGGE profiles of total DNA of cassava dough exhibited 10 distinguishable bands. In contrast, DGGE fingerprints of bacteria recovered from enrichment cultures of fermented dough gave variable profiles containing fewer bands. Bands corresponding to five bacterial species detected by direct PCR-DGGE of total DNA from of cassava dough were also observed in DGGE patterns of enrichment cultures. Eighteen strains were isolated from cultures selected on the basis of their DGGE banding patterns. Assessment of bacterial identification by 16S rDNA sequence similarity revealed that band comigration implied sequence identity. Comparison of 16S rDNA sequences of excised DGGE bands and recovered pure culture isolates with those in GENBANK and the RDP databases revealed that representative bacteria of fermented cassava dough were Lactobacillus and Pediococcus species as well as species of Clostridium, Propionibacterium and Bacillus. Some Lactobacillus species detected in dough samples by sequence analysis of DGGE bands were not recovered in any of the five culture media and conditions used. On the other hand, some species recovered as pure cultures from enrichments were not detected by direct DGGE analysis of total bacterial DNA from cassava dough. Our results provide evidence of the necessity to combine both culture-dependent and culture-independent methods for better description of microbial communities in indigenous cassava starch fermentations.

  2. Different selective effects on rhizosphere bacteria exerted by genetically modified versus conventional potato lines.

    Directory of Open Access Journals (Sweden)

    Armando Cavalcante Franco Dias

    Full Text Available BACKGROUND: In this study, we assessed the actively metabolizing bacteria in the rhizosphere of potato using two potato cultivars, i.e. the genetically-modified (GM cultivar Modena (having tubers with altered starch content and the near-isogenic non-GM cultivar Karnico. To achieve our aims, we pulse-labelled plants at EC90 stage with (13C-CO2 and analysed their rhizosphere microbial communities 24 h, 5 and 12 days following the pulse. In the analyses, phospholipid fatty acid/stable isotope probing (PLFA-SIP as well as RNA-SIP followed by reverse transcription and PCR-DGGE and clone library analysis, were used to determine the bacterial groups that actively respond to the root-released (13C labelled carbonaceous compounds. METHODOLOGY/PRINCIPAL FINDINGS: The PLFA-SIP data revealed major roles of bacteria in the uptake of root-released (13C carbon, which grossly increased with time. Gram-negative bacteria, including members of the genera Pseudomonas and Burkholderia, were strong accumulators of the (13C-labeled compounds at the two cultivars, whereas Gram-positive bacteria were lesser responders. PCR-DGGE analysis of cDNA produced from the two cultivar types showed that these had selected different bacterial, alpha- and betaproteobacterial communities at all time points. Moreover, an effect of time was observed, indicating dynamism in the structure of the active bacterial communities. PCR-DGGE as well as clone library analyses revealed that the main bacterial responders at cultivar Karnico were taxonomically affiliated with the genus Pseudomonas, next to Gluconacetobacter and Paracoccus. Cultivar Modena mainly attracted Burkholderia, next to Moraxella-like (Moraxellaceae family and Sphingomonas types. CONCLUSIONS/SIGNIFICANCE: Based on the use of Pseudomonas and Burkholderia as proxies for differentially-selected bacterial genera, we conclude that the selective forces exerted by potato cultivar Modena on the active bacterial populations differed

  3. A simple remedy against artifactual double bands in denaturing gradient gel electrophoresis

    NARCIS (Netherlands)

    Janse, I.; Bok, J.M.; Zwart, G.

    2004-01-01

    Denaturant gradient gel electrophoresis (DGGE) is a widely used method for mutation analysis and for studies of microbial diversity. Particular combinations of target gene fragments and primers may give rise to erroneous DGGE profiles. We report on a very straightforward means to eliminate the

  4. [FIXED COMBINATION ATORVASTATIN-EZETIMIBE (ATOZET®)].

    Science.gov (United States)

    Scheen, A J

    2016-01-01

    Cardiovascular prevention in subjects at high or very high risk requires a drastic reduction in LDL cholesterol according to the concept "the lower, the better". The combination of an inhibitor of cholesterol synthesis and a selective inhibitor of intestinal absorption results in a complementary and synergistic LDL-lowering activity. Besides a first fixed combination ezetimibe-simvastatin (Inegy®), a new fixed combination is presented, Atozet® that combines atorvastatin and ezetimibe. Because atorvastatin is more potent than simvastatin, this novel fixed combination should facilitate reaching therapeutic goals in terms of LDL cholesterol amongst patients with severe hypercholesterolaemia and/or at high or very high cardiovascular risk.

  5. Design of photonic crystal splitters/combiners

    Science.gov (United States)

    Kim, Sangin; Park, Ikmo; Lim, Hanjo

    2004-10-01

    Photonic band gap (PBG) structures or photonic crystals have attracted a lot of interest since one of their promising applications is to build compact photonic integrated circuits (PIC). One of key components in PICs is a 1 x 2 optical power splitter or a 2 x 1 combiner. Design of 1 x 2 optical power splitters based on photonic crystal has been investigated by several research groups, but no attention has been paid to the design of 2 x 1 optical combiners. In conventional dielectric waveguide based circuits, optical combiners are obtained just by operating the splitters in the opposite direction and the isolation between two input ports in the combiners is naturally achieved. In photonic crystal based circuits, however, we have found that reciprocal operation of the splitters as combiners will not provide proper isolation between the input ports of the combiners. In this work, microwave-circuit concept has been adopted to obtain isolation between two input ports of the combiner and compact optical power splitters/combiners of good performance have been designed using 2-D photonic crystal. Numerical analysis of the designed splitters/combiners has been performed with the finite-difference time-domain method. The designed splitters/combiners show good isolation between input ports in combiner operation with small return losses.

  6. Signatures of Autotrophic and Heterotrophic Metabolic Activity in Enrichment Cultures from a Sulphur Oxidizing Acid Mine Site

    Science.gov (United States)

    Slater, G. F.; Bernier, L.; Cowie, B. R.; Warren, L. A.

    2006-12-01

    Delineating the role of microorganisms in geochemical processes of interest in natural environments requires the development of tools that provide the ability to distinguish amongst microbial activity associated with different metabolic guilds. The gap between phylogenetic characterization and phenotypic understanding remains, underscoring the need to consider alternative methods. Compound specific analysis of cellular components has the potential to differentiate between active metabolic processes supporting microbial communities and may be especially useful in extreme environments. The goal of this study was to determine whether the phospholipids fatty acid (PLFA) distribution and isotopic signatures associated with autotrophs and heterotrophs enriched from an acid mine drainage (AMD) system differed, and further whether natural consortial autotrophic isolates showed similar signatures to autotrophic pure strains of Acidithiobacillus ferrooxidans and A. thiooxidans. Two distinct initial enrichments with tetrathionate and CO2 yielded primarily autotrophic (95%) Acidithiobaccillus spp. sulphur oxidizing communities. The remaining microbial members of theses enrichments (subculture of the consortial isolates in a medium amended with glucose but without tetrathionate selectively resulted in their visible growth. PLFA profiles and δ13C signatures from autotrophic (1) natural enrichments, pure cultures of (2) A. ferrooxidans and (3) A. thiooxidans were similar, but collectively differed from those of the natural heterotrophic enrichment cultures. The PLFA profiles for the heterotrophic communities were made up of primarily (88-99%) C16:0 and two isomers of C18:1. In contrast, the autotrophic communities had high proportions of C16:1 (up to 18%) as well as cyclo C17 and cyclo C19 PLFA that combined comprised 18 to 58% of the observed PLFA. The δ13C signatures of the PLFA also differed strongly between the two trophic levels. The δ13C of the autotrophic PLFA, - 24 to

  7. COMBINED DAMAGE FRACTURE CRITERIA FOR PIEZOELECTRIC CERAMICS

    Institute of Scientific and Technical Information of China (English)

    Yang Xinhua; Chen Chuanyao; Hu Yuantai; Wang Cheng

    2005-01-01

    Mechanical and electrical damages are introduced to study the fracture mechanics of piezoelectric ceramics in this paper. Two kinds of piezoelectric fracture criteria are established using the method of least squares combined with a damage analysis of the well-known piezoelectric fracture experiments of Park and Sun's. One is based on a linear combination of the mechanical and electrical damages and the other on their nonlinear combination. When the combined damage D is up to its critical value Dc, piezoelectric fracture occurs. It is found from the qualitative comparison of the numerical results with the experimental data that the nonlinearly combined damage fracture criterion can give a better prediction of piezoelectric fracture. And it is concluded from the nonlinearly combined damage fracture criterion that a negative electric field impedes fracture whereas the effect of a positive electric field on fracture depends on its magnitude.

  8. Strategy application, observability, and the choice combinator.

    Energy Technology Data Exchange (ETDEWEB)

    Winter, Victor Lono (University of Nebraska at Omaha)

    2004-03-01

    In many strategic systems, the choice combinator provides a powerful mechanism for controlling the application of rules and strategies to terms. The ability of the choice combinator to exercise control over rewriting is based on the premise that the success and failure of strategy application can be observed. In this paper we present a higher-order strategic framework with the ability to dynamically construct strategies containing the choice combinator. To this framework, a combinator called hide is introduced that prevents the successful application of a strategy from being observed by the choice combinator. We then explore the impact of this new combinator on a real-world problem involving a restricted implementation of the Java Virtual Machine.

  9. Using Combinational Circuits for Control Purposes

    Directory of Open Access Journals (Sweden)

    Maher A. Nabulsi

    2009-01-01

    Full Text Available Problem statement: Combinational circuits are used in computers for generating binary control decisions and for providing digital components for data processing. Approach: The use of combinational circuits and logic gates to control other circuits was discussed. Different systems that use logic gates, multiplexers, decoders and encoders to control different circuits were presented. This study presented a design and implementation of some combinational circuits such as a decoder, an encoder, a multiplexer, a bus system and read/write memory operations. Results: When we connected some types of combinational circuits to the inputs/outputs of digital circuit, these combinational circuits can help us to manage and flow a different types of control signals through a large digital circuit. Conclusion: Many combinational circuits had a good function which can be used for controlling different parts of any digital system and they produce a suitable way to transfer a control signals between different digital components of any large digital system.

  10. Systemic combination treatment for psoriasis: a review

    DEFF Research Database (Denmark)

    Jensen, Peter; Skov, Lone; Zachariae, Claus

    2010-01-01

    Psoriasis is a chronic inflammatory skin disease, which affects approximately 2.6% of the population in Northern Europe and Scandinavia. In order to achieve disease control, combinations of systemic treatments are sometimes needed for variable time periods. However, no evidence-based guidelines...... exist for the use of systemic combination therapy. Therefore, our aim was to review the current literature on systemic anti-psoriatic combination regimens. We searched PubMed and identified 98 papers describing 116 studies (23 randomized) reporting on the effect of various systemic combination...

  11. New nomenclatural combinations in Pseuduvaria (Annonaceae)

    NARCIS (Netherlands)

    Su, Yvonne C.F.; Saunders, Richard M.K.

    2001-01-01

    New nomenclatural combinations are validated for Pseuduvaria oxycarpa (transferred from Mitrephora) and P. luzonensis, P. unguiculata and P. pamattonis (all transferred from Orophea). All names are lectotypified.

  12. Combined Pharmacologic Therapy in Postmenopausal Osteoporosis.

    Science.gov (United States)

    Shen, Yang; Gray, Dona L; Martinez, Dorothy S

    2017-03-01

    Antiresorptive agents for treating postmenopausal osteoporosis include selective estrogen receptor modulator (SERM), bisphosphonates and denoumab. Teriparatide is the only Food and Drug Administration-approved anabolic agent. Synergistic effects of combining teriparatide with an antiresorptive agent have been proposed and studied. This article reviews the trial designs and the outcomes of combination therapies. Results of the combination therapy for teriparatide and bisphosphonates were mixed; while small increases of bone density were observed in the combination therapy of teriparatide and estrogen/SERM and that of teriparatide and denosumab. Those clinical studies were limited by small sample sizes and lack of fracture outcomes.

  13. Adding source positions to the IVS Combination

    Science.gov (United States)

    Bachmann, S.; Thaller, D.

    2016-12-01

    Simultaneous estimation of source positions, Earth orientation parameters (EOPs) and station positions in one common adjustment is crucial for a consistent generation of celestial and terrestrial reference frame (CRF and TRF, respectively). VLBI is the only technique to guarantee this consistency. Previous publications showed that the VLBI intra-technique combination could improve the quality of the EOPs and station coordinates compared to the individual contributions. By now, the combination of EOP and station coordinates is well established within the IVS and in combination with other space geodetic techniques (e.g. inter-technique combined TRF like the ITRF). Most of the contributing IVS Analysis Centers (AC) now provide source positions as a third parameter type (besides EOP and station coordinates), which have not been used for an operational combined solution yet. A strategy for the combination of source positions has been developed and integrated into the routine IVS combination. Investigations are carried out to compare the source positions derived from different IVS ACs with the combined estimates to verify whether the source positions are improved by the combination, as it has been proven for EOP and station coordinates. Furthermore, global solutions of source positions, i.e., so-called catalogues describing a CRF, are generated consistently with the TRF similar to the IVS operational combined quarterly solution. The combined solutions of the source positions time series and the consistently generated TRF and CRF are compared internally to the individual solutions of the ACs as well as to external CRF catalogues and TRFs. Additionally, comparisons of EOPs based on different CRF solutions are presented as an outlook for consistent EOP, CRF and TRF realizations.

  14. Multimorbidity Combinations and Disability in Older Adults.

    Science.gov (United States)

    Quiñones, Ana R; Markwardt, Sheila; Botoseneanu, Anda

    2016-06-01

    Multimorbidity (multiple co-occurring chronic diseases) is associated with greater likelihood of disability and mortality, above and beyond the risk attributable to individual diseases. This study identifies prevalent multimorbidity patterns and evaluates their association with disability among U.S. older adults. Prospective cohort study using longitudinal Health and Retirement Study data (2010-2012). We included 8,782 participants aged 65 years and older and used negative binomial models to examine prospective disability, measured by the combined activities of daily living-instrumental activities of daily living index. Multimorbidity was defined as the co-occurring combination of at least two of the following chronic diseases: hypertension, cardiovascular disease, lung disease, diabetes, cancer, arthritis, stroke, cognitive impairment, or high depressive symptoms (CES-D score ≥ 4). We found 291 unique disease combinations with 1 to 1,167 older adults per disease combination. The three most prevalent combinations were: (a) hypertension and arthritis (n = 1,167); (b) hypertension, arthritis, and cardiovascular disease (n = 510); and (c) hypertension, arthritis, and diabetes (n = 430). Only one of the prevalent combinations included depressive symptoms (in combination with arthritis, hypertension; n = 129). This group showed the highest level of activities of daily living-instrumental activities of daily living disability compared to healthy participants or participants with a single disease (either included in the combination or different from diseases in the combination) even after adjusting for age, gender, education, race/ethnicity, and body mass index. Clinicians stand to gain from a better understanding of which disease combinations are more and less disabling among older adults. Understanding how multimorbidity combinations relate to functional status is an important step towards reducing disability and sustaining independent living among older adults.

  15. Results from combined CMS-TOTEM data

    CERN Document Server

    Sen, Sercan

    2016-01-01

    The combined data taking of the CMS and TOTEM experiments allows to characterize hadronic final states in an extremely wide pseudo-rapidity range and opens up a window to a rich diffractive/forward physics program. In this paper, the trigger strategy of the common data taking is described, and the physics results from combined CMS-TOTEM data is presented.

  16. 27 CFR 6.93 - Combination packaging.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Combination packaging. 6..., DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exceptions § 6.93 Combination packaging. The act by an industry member of packaging and distributing distilled spirits, wine, or malt beverages in...

  17. Fused combiners for photonic crystal bers

    DEFF Research Database (Denmark)

    Noordegraaf, Danny

    The work presented in this Ph.D. thesis focuses on the fabrication of fused combiners for high-power fiber lasers and amplifiers. The main focus of the Ph.D. project was to further develop the fused pump combiners for airclad photonic crystal bers (PCFs), and implement a signal feed...

  18. Convergence analysis of combinations of different methods

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Y. [Clarkson Univ., Potsdam, NY (United States)

    1994-12-31

    This paper provides a convergence analysis for combinations of different numerical methods for solving systems of differential equations. The author proves that combinations of two convergent linear multistep methods or Runge-Kutta methods produce a new convergent method of which the order is equal to the smaller order of the two original methods.

  19. A linear combination of modified Bessel functions

    Science.gov (United States)

    Shitzer, A.; Chato, J. C.

    1971-01-01

    A linear combination of modified Bessel functions is defined, discussed briefly, and tabulated. This combination was found to recur in the analysis of various heat transfer problems and in the analysis of the thermal behavior of living tissue when modeled by cylindrical shells.

  20. Safety considerations with fenofibrate/simvastatin combination.

    Science.gov (United States)

    Filippatos, Theodosios D; Elisaf, Moses S

    2015-01-01

    Fenofibrate/simvastatin combination is useful for patients with mixed dyslipidemia. Aim of this review is to critically present the safety aspects of the fenofibrate/simvastatin combination. Current evidence regarding the adverse effects of fenofibrate/simvastatin combination is critically presented based on the results of large randomized controlled trials and other relevant studies. Additionally, clinical pharmacology, drug interactions and the effects of fenofibrate and simvastatin on metabolic variables and cardiovascular risk are briefly described. Large randomized clinical trials show that the combined administration of fenofibrate with simvastatin is not associated with significantly increased incidence of serious adverse events compared with simvastatin monotherapy. The incidence of rhabdomyolysis is slightly increased with fibrate/statin combination compared with monotherapy but the actual risk is very low. Although fenofibrate increases creatinine and homocysteine serum levels, the incidence of diabetic nephropathy and thrombotic events was not significantly increased with fenofibrate/simvastatin combination compared with simvastatin monotherapy in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) Lipid trial. Furthermore, a decrease in albuminuria was observed with fenofibrate in the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) and ACCORD Lipid trials. Overall, the combined administration of fenofibrate with simvastatin appears to be safe, unless clinicians give fenofibrate/simvastatin combination to patients with predisposing risk factors for the occurrence of adverse events.

  1. Multimedia: How to Combine Language and Visuals

    Directory of Open Access Journals (Sweden)

    Holger Horz

    2008-08-01

    Full Text Available In the last decade, advanced computer technology has allowed for development of information systems and learning environments that combine language with other forms of human communication in innovative ways. Language in the form of written texts, for example, can be combined not only with static pictures or graphs as in printed material, but also with animation or video.

  2. Building program understanding tools using visitor combinators

    NARCIS (Netherlands)

    Deursen, A. van; Visser, J.M.W.

    2002-01-01

    Program understanding tools manipulate program representations, such as abstract syntax trees, control-flow graphs, or data-flow graphs. This paper deals with the use of visitor combinators to conduct such manipulations. Visitor combinators are an extension of the well-known visitor design

  3. Combining Neural Networks for Skin Detection

    CERN Document Server

    Doukim, Chelsia Amy; Chekima, Ali; Omatu, Sigeru

    2011-01-01

    Two types of combining strategies were evaluated namely combining skin features and combining skin classifiers. Several combining rules were applied where the outputs of the skin classifiers are combined using binary operators such as the AND and the OR operators, "Voting", "Sum of Weights" and a new neural network. Three chrominance components from the YCbCr colour space that gave the highest correct detection on their single feature MLP were selected as the combining parameters. A major issue in designing a MLP neural network is to determine the optimal number of hidden units given a set of training patterns. Therefore, a "coarse to fine search" method to find the number of neurons in the hidden layer is proposed. The strategy of combining Cb/Cr and Cr features improved the correct detection by 3.01% compared to the best single feature MLP given by Cb-Cr. The strategy of combining the outputs of three skin classifiers using the "Sum of Weights" rule further improved the correct detection by 4.38% compared t...

  4. Combined cycles with gas turbine engines

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, Y.S.H.; Akyurt, M. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Mechanical Engineering Dept.)

    1994-03-01

    Simple cycle gas turbine engines suffer from limited efficiencies and consequential dominance of fuel prices on generation costs. Combined cycles, however. exploit the waste heat from exhaust gases to boost power output, resulting in overall efficiencies around 50%, which are significantly above those of steam power plants. This paper reviews various types of combined cycles, including repowering, integrated gasification and other advanced systems. (author)

  5. [Age peculiarities of combined maxillofacial injuries treatment].

    Science.gov (United States)

    Kharitonov, D Iu

    2008-01-01

    Experience of help to 399 patients with combined craniofacial traumas of different age groups was shown. Some algorithm of help to such patients was suggested, interaction of craniofacial trauma components were demonstrated. Some scheme of pathogenetic based treatment of patients with combined craniofacial injuries was grounded upon it.

  6. The GRAVITY integrated optics beam combination

    Science.gov (United States)

    Jocou, L.; Perraut, K.; Nolot, A.; Berger, J. P.; Moulin, T.; Labeye, P.; Lacour, S.; Perrin, G.; Lebouquin, J. B.; Bartko, H.; Thiel, M.; Eisenhauer, F.

    2010-07-01

    Gravity is a 2nd generation interferometric instrument for VLTI. It will combine 4 telescopes in dual feed in the K band to study general relativity effects around the Galactic Center black hole. The concept of Gravity is based on two equivalent beam combiner instruments: the scientific one fed by the science target (Sgr A*) and the fringe tracker fed by a bright reference star (See Gillessen et al.1). Both beam combination instruments are based on silica on silicon integrated optics (IO) component glued to fluoride glass fiber array. The beam combiners are implemented in a cryogenic vessel cooled at 200°K and back-illuminated by a high power laser used for metrology (Bartko et al.2). This paper is dedicated to the description of the development of the integrated beam combiner assembly.

  7. Dynamic Bayesian Combination of Multiple Imperfect Classifiers

    CERN Document Server

    Simpson, Edwin; Psorakis, Ioannis; Smith, Arfon

    2012-01-01

    Classifier combination methods need to make best use of the outputs of multiple, imperfect classifiers to enable higher accuracy classifications. In many situations, such as when human decisions need to be combined, the base decisions can vary enormously in reliability. A Bayesian approach to such uncertain combination allows us to infer the differences in performance between individuals and to incorporate any available prior knowledge about their abilities when training data is sparse. In this paper we explore Bayesian classifier combination, using the computationally efficient framework of variational Bayesian inference. We apply the approach to real data from a large citizen science project, Galaxy Zoo Supernovae, and show that our method far outperforms other established approaches to imperfect decision combination. We go on to analyse the putative community structure of the decision makers, based on their inferred decision making strategies, and show that natural groupings are formed. Finally we present ...

  8. Crankshaft position sensing with combined starter alternator

    Science.gov (United States)

    Brandenburg, Larry Raymond; Miller, John Michael

    2000-06-13

    A crankshaft position sensing apparatus for use with an engine (16) having a combined starter/alternator assembly (18). The crankshaft position sensing apparatus includes a tone ring (38) with a sensor (36) and bandpass filter (46), having a cylinder identification input from a camshaft sensor (48), and a gain limiter (54). The sensing apparatus mounts near the rotor (30) of the combined starter/alternator assembly (18). The filtered crankshaft position signal can then be input into a vehicle system controller (58) and an inner loop controller (60). The starter/alternator assembly (18) in combination with an internal combustion engine is particularly useful for a hybrid electric vehicle system.

  9. Beam combining of quantum cascade laser arrays.

    Science.gov (United States)

    Lee, Benjamin G; Kansky, Jan; Goyal, Anish K; Pflügl, Christian; Diehl, Laurent; Belkin, Mikhail A; Sanchez, Antonio; Capasso, Federico A

    2009-08-31

    Wavelength beam combining was used to co-propagate beams from 28 elements in an array of distributed-feedback quantum cascade lasers (DFB-QCLs). The beam-quality product of the array, defined as the product of near-field spot size and far-field divergence for the entire array, was improved by a factor of 21 by using wavelength beam combining. To demonstrate the applicability of wavelength beam combined DFB-QCL arrays for remote sensing, we obtained the absorption spectrum of isopropanol at a distance of 6 m from the laser array.

  10. Combined Sparsifying Transforms for Compressive Image Fusion

    Directory of Open Access Journals (Sweden)

    ZHAO, L.

    2013-11-01

    Full Text Available In this paper, we present a new compressive image fusion method based on combined sparsifying transforms. First, the framework of compressive image fusion is introduced briefly. Then, combined sparsifying transforms are presented to enhance the sparsity of images. Finally, a reconstruction algorithm based on the nonlinear conjugate gradient is presented to get the fused image. The simulations demonstrate that by using the combined sparsifying transforms better results can be achieved in terms of both the subjective visual effect and the objective evaluation indexes than using only a single sparsifying transform for compressive image fusion.

  11. Combination solar photovoltaic heat engine energy converter

    Science.gov (United States)

    Chubb, Donald L.

    1987-01-01

    A combination solar photovoltaic heat engine converter is proposed. Such a system is suitable for either terrestrial or space power applications. The combination system has a higher efficiency than either the photovoltaic array or the heat engine alone can attain. Advantages in concentrator and radiator area and receiver mass of the photovoltaic heat engine system over a heat-engine-only system are estimated. A mass and area comparison between the proposed space station organic Rankine power system and a combination PV-heat engine system is made. The critical problem for the proposed converter is the necessity for high temperature photovoltaic array operation. Estimates of the required photovoltaic temperature are presented.

  12. Combined algorithms in nonlinear problems of magnetostatics

    Energy Technology Data Exchange (ETDEWEB)

    Gregus, M.; Khoromsky, B.N.; Mazurkevich, G.E.; Zhidkov, E.P.

    1988-05-09

    To solve boundary problems of magnetostatics in unbounded two- or three-dimensional regions, we construct combined algorithms based on a combination of the method of boundary integral equations with the grid methods. We study the question of substantiation of the combined method in nonlinear magnetostatic problems without the preliminary discretization of equations and give some results on the convergence of iterative processes that arise in nonlinear cases. We also discuss economical iterative processes and algorithms that solve boundary integral equations on certain surfaces. Finally, examples of numerical solutions of magnetostatic problems that arose when modelling the fields of electrophysical installations are given, too. 14 refs., 2 figs.

  13. NFL Combine Athletic Performance after ACL Reconstruction

    National Research Council Canada - National Science Library

    Marshall, Nathan E; Keller, Robert A; Mehran, Nima; Austin, William; Moutzouros, Vasilios

    2016-01-01

    Objectives: The purpose of this study was to determine the functional performance of NFL combine participants after ACL reconstruction compared with an age-, size-, and position-matched control group...

  14. Ameliorative Effects of Herbal Combinations in Hyperlipidemia

    Directory of Open Access Journals (Sweden)

    Nishant P. Visavadiya

    2011-01-01

    Full Text Available The roots of Glycyrrhiza glabra, Withania somnifera, Asparagus racemosus, and Chlorophytum borivilianum and seeds of Sesamum indicum are ayurvedic medicinal plants used in India to treat several ailments. Our previous studies indicated that these plants possess hypolipidemic and antioxidant potential. The present study was aimed at investigating the composite effects of these plants on hypercholesterolemic rats. Three different combinations (5 gm%, given for four weeks used in this study effectively reduced plasma and hepatic lipid profiles and increased fecal excretion of cholesterol, neutral sterol, and bile acid along with increasing the hepatic HMG-CoA reductase activity and bile acid content in hypercholesterolemic rats. Further, all three combinations also improved the hepatic antioxidant status (catalase, SOD, and ascorbic acid levels and plasma total antioxidant capacity with reduced hepatic lipid peroxidation. Overall, combination I had the maximum effect on hypercholesterolemic rats followed by combinations II and III due to varying concentrations of the different classes of phytocomponents.

  15. Current update on combined hepatocellular-cholangiocarcinoma

    Directory of Open Access Journals (Sweden)

    Suresh Maximin

    2014-01-01

    Combined hepatocellular cholangiocarcinoma tends to present with an more aggressive behavior and a poorer prognosis than either hepatocellular carcinoma or cholangiocarcinoma. An accurate preoperative diagnosis and aggressive treatment planning can play crucial roles in appropriate patient management.

  16. Optimizing sales areas of combined transport chains

    Directory of Open Access Journals (Sweden)

    Philip Michalk

    2013-12-01

    Full Text Available Background: Combined transport chains (such as intermodal transport, have certain advantages. The main advantage from customer points of view is the possibility to bundle freight and thereby decrease transport costs. On the other hand, a combined transport chain can cause longer transport times, due to the necessary transshipment processes. Methods: The area around a terminal, in which a combined service has favourable properties to a customer in comparison to a direct transport, can be understood as a sales-area, in which a combined transport product is marketable. The aim of this paper was to find a method to determine the best shape and size of this area. Results and conclusions: The paper at hand lined out a method in order to calculate such a sales area and determine which geographical points around a terminal have an advantage in comparison to a direct transport service.

  17. Combined photoultrasonic treatment of infected wounds

    Science.gov (United States)

    Zharov, Vladimir P.; Menyaev, Yulian A.; Kalinin, Konstantin L.; Zmievskoy, Gregory N.; Velsher, Leonid Z.; Podkolzin, Alexander A.; Stakhanov, Mikhail L.; Gorchak, Yury Y.; Sarantsev, V. P.

    2001-05-01

    A new combined photoultrasonic (CPUS) technology for the treatment of infected wounds is suggested. The CPUS principal operation is based on the topical application of a photosensitizer followed by light irradiation in combination with low frequency ultrasonic (US) treatment of wounds. In CPUS, two methods - photodynamic (PDT) and ultrasonic therapies supplement each other beneficially and in conjunction provide a significant effect of deep suppurative inflammatory wounds treatment. The main advantages of the new technology are the combined application of an antibiotic solution and photodynamic therapy to destroy antibiotic- resistant microorganisms, an effective mixing of a photosensitizer in the wound, the US enhancement of photosensitizer impregnation into the membranes of bacteria, the US clearing of wound surface from necrotic products, an increased effective light dose exposure in the whole volume of the deep wound when the light does not penetrate totally inside the wound, an additional bactericidal effect under the US impact, and the combined effect of CPUS activation of the immune system.

  18. Combination Classes and "Hora de comunicacion."

    Science.gov (United States)

    Eldredge, Dee L.

    1989-01-01

    Ways to combine small classes of higher education students studying Spanish at various levels are described, including judicious use of language laboratories, staggering of the different level groups, and rotation of activities geared toward students' individual proficiency levels. (CB)

  19. Novel Combination Chemotherapy for Localized Ewing Sarcoma

    Science.gov (United States)

    In this clinical trial, researchers will test whether the addition of the drug combination vincristine, topotecan, and cyclophosphamide to a standard chemotherapy regimen improves overall survival in patients with extracranial Ewing

  20. Power combining considerations for Prometheus TWTAs

    Science.gov (United States)

    Komm, David S.; Smith, S. K.; Menninger, W. L.

    2005-01-01

    This slide presentation reviws the planning for a nuclear-electric spacecraft. It includes information concerning one considered mission, communications requirements, power combining, four-beam cluster antenna, and amplitude and phase variations.

  1. OT-Combiners Via Secure Computation

    DEFF Research Database (Denmark)

    Harnik, Danny; Ishai, Yuval; Kushilevitz, Eyal

    2008-01-01

    An OT-combiner implements a secure oblivious transfer (OT) protocol using oracle access to n OT-candidates of which at most t may be faulty. We introduce a new general approach for combining OTs by making a simple and modular use of protocols for secure computation. Specifically, we obtain an OT......, in a network consisting of a single OT-channel. Our approach applies both to the “semi-honest” and the “malicious” models of secure computation, yielding the corresponding types of OT-combiners. Instantiating our general approach with secure computation protocols from the literature, we conceptually simplify......-combiner from any instantiation of the following two ingredients: (1) a t-secure n-party protocol for the OT functionality, in a network consisting of secure point-to-point channels and a broadcast primitive; and (2) a secure two-party protocol for a functionality determined by the former multiparty protocol...

  2. Effects of pioglitazone in familial combined hyperlipidaemia.

    NARCIS (Netherlands)

    Abbink-Zandbergen, E.J.; Graaf, J. de; Haan, J.H.A. de; Heerschap, A.; Stalenhoef, A.F.H.; Tack, C.J.J.

    2006-01-01

    OBJECTIVES: Familial combined hyperlipidaemia (FCH) is associated with insulin resistance. We hypothesized that pioglitazone treatment of FCH patients might increase insulin sensitivity, but may also improve serum lipid levels, body fat distribution, intramyocellular lipids (IMCL) and endothelial fu

  3. Combination Classes and "Hora de comunicacion."

    Science.gov (United States)

    Eldredge, Dee L.

    1989-01-01

    Ways to combine small classes of higher education students studying Spanish at various levels are described, including judicious use of language laboratories, staggering of the different level groups, and rotation of activities geared toward students' individual proficiency levels. (CB)

  4. Combined Control Scheme for Monitoring Quality Characteristics

    Directory of Open Access Journals (Sweden)

    Adekeye K.S.

    2014-07-01

    Full Text Available In the literature, the Exponentially Weighted Moving Average (EWMA and Exponentially Weighted Moving Variance (EMWV control schemes have been used separately to monitor the process average and process variability respectively. Here the two are combined and applied on simulated process with different level of variation. The control limit interval (CLI and the average run length (ARL were evaluated for the combined chart. The combined chart performed better than the two independently. Furthermore, an algorithm was developed for the two control charts and implemented on visual basic VB6.0. The obtained results show that the combined EWMA and EWMV control chart is very sensitive in detecting shift in production process and every shift in the process mean is always preceded by shift in the process variability.

  5. Comparison of accounting methods for business combinations

    Directory of Open Access Journals (Sweden)

    Jaroslav Sedláček

    2012-01-01

    Full Text Available The revised accounting rules applicable to business combinations in force on July1st 2009, are the result of several years efforts the convergence of U.S. and International Committee of the Financial Accounting Standards. Following the harmonization of global accounting procedures are revised and implemented also Czech accounting regulations. In our research we wanted to see how changes can affect the strategy and timing of business combinations. Comparative analysis is mainly focused on the differences between U.S. and international accounting policies and Czech accounting regulations. Key areas of analysis and synthesis are the identification of business combination, accounting methods for business combinations and goodwill recognition. The result is to assess the impact of the identified differences in the reported financial position and profit or loss of company.

  6. Target recognition based on modified combination rule

    Institute of Scientific and Technical Information of China (English)

    Chen Tianlu; Que Peiwen

    2006-01-01

    Evidence theory is widely used in the field of target recognition. The invalidation problem of this theory when dealing with highly conflict evidences is a research hotspot. Several alternatives of the combination rule are analyzed and compared. A new combination approach is proposed. Calculate the reliabilities of evidence sources using existing evidences. Construct reliabilities judge matrixes and get the weights of each evidence source. Weight average all inputted evidences. Combine processed evidences with D-S combination rule repeatedly to identify a target. The application in multi-sensor target recognition as well as the comparison with typical alternatives all validated that this approach can dispose highly conflict evidences efficiently and get reasonable recognition results rapidly.

  7. Determination of hormonal combination for increased multiplication ...

    African Journals Online (AJOL)

    ACSS

    multiplication of tissue culture potato plantlets. F. Nuwagira1,3, S.B. ... are genotype dependant. The use of higher .... hormonal combinations and the interaction showed no ..... PhD Thesis, ... Environment and Industrial Innovation. Volume 12.

  8. Beam Combination for Sparse Aperture Telescopes Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is for funding to continue development of an alternative beam combiner for Stellar Imager (SI), a 30-aperture, interferometric telescope chosen as one...

  9. Combining Stocks and Flows of Knowledge

    DEFF Research Database (Denmark)

    Ambos, Tina C.; Nell, Phillip Christopher; Pedersen, Torben

    2013-01-01

    While previous research has mostly focused on either knowledge stocks or knowledge flows, our study is among the first to integrate these perspectives in order to shed light on the complementarity effects of different types of knowledge stocks and flows in the multinational corporation (MNC...... of complementarity create benefits for these units, but that the effects from intra-functional combinations of knowledge stocks and flows are significantly stronger than from cross-functional combinations....

  10. A Shrinkage Estimator for Combination of Bioassays

    Institute of Scientific and Technical Information of China (English)

    Jian Xiong; D.G. Chen; Zhen-hai Yang

    2007-01-01

    A shrinkage estimator and a maximum likelihood estimator are proposed in this paper for combination of bioassays. The shrinkage estimator is obtained in closed form which incorporates prior information just on the common log relative potency after the homogeneity test for combination of bioassays is accepted. It is a practical improvement over other estimators which require iterative procedure to obtain the estimator for the relative potency. A real data is also used to show the superiorities for the newly-proposed procedures.

  11. PROBLEMATIC ISSUES OF COMBINED INTESTINAL INFECTIONS

    Directory of Open Access Journals (Sweden)

    V. V. Shkarin

    2016-01-01

    Full Text Available The  article  presents the  possible combinations of intestinal   infections of  various   etiologies, some   pathogenetic, clinical  and  epidemiological features and  problems of epidemiological surveillance and  control  of  associated infections.  Details  the  combination of typhoid fever,  shigelloses, salmonelloses, yersiniosis, pseudotuberculosis, rotavirus and norovirus infections between itself  and  other  infectious and parasitic diseases. Discusses the clinical  and  epidemiological features different combinations of intestinal infections. It is shown  that  the proportion of combined intestinal infections  can reach  to 48.9±3.3% in the structure of all associated  infections. The proportion of combination of two intestinal  infections pathogens was  29,2±6,5%, 3 agents and 10,3±4,3% and  4 pathogens and  5,9±11,6 percent. In the overall structure of the combination of intestinal anthroponoses with anthroponoses was 61,9±5,3%, anthroponoses with zoonoses was 31,1±5,0%, the other combinations (zoonoses and  zoonoses, zoonoses and  sapronoses, antroponoses with zoonoses and  sapronoses of  7,0±9,3  percent. The  article raises  the  question of  the  need to  introduce into  existing regulatory framework the  new  scientific data  on the  whole range of features of the epidemiology of intestinal infections combined.

  12. RF waveguide phase-directed power combiners

    Energy Technology Data Exchange (ETDEWEB)

    Nantista, Christopher D.; Dolgashev, Valery A.; Tantawi, Sami G.

    2017-05-02

    High power RF phase-directed power combiners include magic H hybrid and/or superhybrid circuits oriented in orthogonal H-planes and connected using E-plane bends and/or twists to produce compact 3D waveguide circuits, including 8.times.8 and 16.times.16 combiners. Using phase control at the input ports, RF power can be directed to a single output port, enabling fast switching between output ports for applications such as multi-angle radiation therapy.

  13. [Combined radio- and chemotherapy of anal cancer].

    Science.gov (United States)

    Dobrowsky, W

    1986-05-30

    The treatment regime in anal carcinoma is changing from being a mainly surgical problem. Combined radio-chemotherapy is of increasing interest as treatment of choice. The new treatment modality, including chemotherapy with Mitomycin C and 5-fluorouracil combined with percutaneous and interstitial radiotherapy is presented. The treatment regimes performed at the University Department for Radiotherapy and Radiobiology Vienna is discussed with regard to tolerance, side effects and local control.

  14. Analytic image concept combined to SENSE reconstruction

    OpenAIRE

    Yankam Njiwa, J; Baltes, C.; Rudin, M.

    2011-01-01

    Two approaches of reconstructing undersampled partial k-space data, acquired with multiple coils are compared: homodyne detection combined with SENSE (HM_SENSE) and analytic image reconstruction combined with SENSE (AI_SENSE). The latter overcomes limitations of HM_ SENSE by considering aliased images as analytic thus avoiding the need for phase correction required for HM_SENSE. MATERIALS AND METHODS: In vivo imaging experiments were carried out in male Lewis rats using both gradient echo...

  15. Holographic Combiners for Head-Up Displays

    Science.gov (United States)

    1977-10-01

    AFAL-TR-77 -110 S HOLOGRAPHIC COMBINERS FOR HEAD-UP DISPLAYS S Radar and Optics Division Environmental Research Institute of Michigan P.O. Box 8618...to 200. SECURITY CLASSIFICATION OF THIS PAGE(RWihen Data Entered) FOREWORD This report was prepared by the Radar and Optics Division of the...with fringes parallel to the surface......31 Figure 13. Raytrace through the F-4 HUD with a holographic combiner

  16. Combined treatment for complex intracranial aneurysm

    OpenAIRE

    Chiriac A.; Ion Georgiana; Dobrin N.; Iencean St.M.; Poeata I.

    2015-01-01

    Complex aneurysms often cannot be completely excluded by a single approaches. Today successful treatment of these lesions requires a combination between microsurgical and endovascular techniques. Planning of combined treatment require a very good understanding of aneurysm anatomy and a close collaboration between neurosurgeon and neuroendovascular interventionist. Endovascular coiling can usually be used as early treatment for a partially aneurysm occlusion including the ruptured area and fol...

  17. Automatic Synthesis of Multilevel Combinational Logic

    DEFF Research Database (Denmark)

    Andersen, Anders C.; Madsen, Jan; Madsen, J.R.

    1989-01-01

    This paper describes a system for the synthesis of multilevel combinational logic, transforming functional description into mask layout. The system includes a logic synthesis part, partly consisting of tools developed at Eindhoven University of Technology, which has been interfaced to the layout...... synthesis part in the CATOE-system, developed at the DesignCenter of Electronics Institute. The various steps in the transformation are presented together with a complete design example, implementing a multi-output combinational decoder function....

  18. Combined surface and volumetric occlusion shading

    KAUST Repository

    Schott, Matthias O.

    2012-02-01

    In this paper, a method for interactive direct volume rendering is proposed that computes ambient occlusion effects for visualizations that combine both volumetric and geometric primitives, specifically tube shaped geometric objects representing streamlines, magnetic field lines or DTI fiber tracts. The proposed algorithm extends the recently proposed Directional Occlusion Shading model to allow the rendering of those geometric shapes in combination with a context providing 3D volume, considering mutual occlusion between structures represented by a volume or geometry. © 2012 IEEE.

  19. Combining calcium imaging with other optical techniques.

    Science.gov (United States)

    Canepari, Marco; Zecevic, Dejan; Vogt, Kaspar E; Ogden, David; De Waard, Michel

    2013-12-01

    Ca(2+) imaging is a commonly used approach for measuring Ca(2+) signals at high spatial resolution. The method is often combined with electrode recordings to correlate electrical and chemical signals or to investigate Ca(2+) signals following an electrical stimulation. To obtain information on electrical activity at the same spatial resolution, Ca(2+) imaging must be combined with membrane potential imaging. Similarly, stimulation of subcellular compartments requires photostimulation. Thus, combining Ca(2+) imaging with an additional optical technique facilitates the study of a number of physiological questions. The aim of this article is to introduce some basic principles regarding the combination of Ca(2+) imaging with other optical techniques. We discuss the design of the optics, the design of experimental protocols, the optical characteristics of Ca(2+) indicators used in combination with an optical probe, and the affinity of the Ca(2+) indicator in relation to the type of measurement. This information will enable the reader to devise an optimal strategy for combined optical experiments.

  20. SPS solid state antenna power combiner

    Science.gov (United States)

    Fitzsimmons, G. W.

    1980-01-01

    A concept for a solar power satellite antenna power combiner which utilizes solid state dc-rf converters is described. To avoid the power combining losses associated with circuit hybrids it is proposed that the power from multiple solid state amplifiers be combined by direct coupling of each amplifier's output to the radiating antenna structure. The selected power-combining antenna consists of a printed (metalized) microstrip circuit on a ceramic type dielectric substrate which is backed by a shallow lightweight aluminum cavity which sums the power of four microwave sources. The antenna behaves like two one-half wavelength slot-line antennas coupled together via their common cavity structure. A significant feature of the antenna configuration selected is that the radiated energy is summed to yield a single radiated output phase which represents the average insertion phase of the four power amplifiers. This energy may be sampled and, by comparison with the input signal, one can phase error correct to maintain the insertion phase of all solid state power combining modules at exactly the same value. This insures that the insertion phase of each SPS power combining antenna module is identical. An experiment verification program is described.

  1. Combination therapy in hypertension: An update

    Directory of Open Access Journals (Sweden)

    Kalra Sanjay

    2010-06-01

    Full Text Available Abstract Meticulous control of blood pressure is required in patients with hypertension to produce the maximum reduction in clinical cardiovascular end points, especially in patients with comorbidities like diabetes mellitus where more aggressive blood pressure lowering might be beneficial. Recent clinical trials suggest that the approach of using monotherapy for the control of hypertension is not likely to be successful in most patients. Combination therapy may be theoretically favored by the fact that multiple factors contribute to hypertension, and achieving control of blood pressure with single agent acting through one particular mechanism may not be possible. Regimens can either be fixed dose combinations or drugs added sequentially one after other. Combining the drugs makes them available in a convenient dosing format, lower the dose of individual component, thus, reducing the side effects and improving compliance. Classes of antihypertensive agents which have been commonly used are angiotensin receptor blockers, thiazide diuretics, beta and alpha blockers, calcium antagonists and angiotensin-converting enzyme inhibitors. Thiazide diuretics and calcium channel blockers are effective, as well as combinations that include renin-angiotensin-aldosterone system blockers, in reducing BP. The majority of currently available fixed-dose combinations are diuretic-based. Combinations may be individualized according to the presence of comorbidities like diabetes mellitus, chronic renal failure, heart failure, thyroid disorders and for special population groups like elderly and pregnant females.

  2. Forecast Combination under Heavy-Tailed Errors

    Directory of Open Access Journals (Sweden)

    Gang Cheng

    2015-11-01

    Full Text Available Forecast combination has been proven to be a very important technique to obtain accurate predictions for various applications in economics, finance, marketing and many other areas. In many applications, forecast errors exhibit heavy-tailed behaviors for various reasons. Unfortunately, to our knowledge, little has been done to obtain reliable forecast combinations for such situations. The familiar forecast combination methods, such as simple average, least squares regression or those based on the variance-covariance of the forecasts, may perform very poorly due to the fact that outliers tend to occur, and they make these methods have unstable weights, leading to un-robust forecasts. To address this problem, in this paper, we propose two nonparametric forecast combination methods. One is specially proposed for the situations in which the forecast errors are strongly believed to have heavy tails that can be modeled by a scaled Student’s t-distribution; the other is designed for relatively more general situations when there is a lack of strong or consistent evidence on the tail behaviors of the forecast errors due to a shortage of data and/or an evolving data-generating process. Adaptive risk bounds of both methods are developed. They show that the resulting combined forecasts yield near optimal mean forecast errors relative to the candidate forecasts. Simulations and a real example demonstrate their superior performance in that they indeed tend to have significantly smaller prediction errors than the previous combination methods in the presence of forecast outliers.

  3. Simultaneous laparoscopic multi-organ resection combined with colorectal cancer: Comparison with non-combined surgery

    Institute of Scientific and Technical Information of China (English)

    Hye Jin Kim; Gyu-Seog Choi; Jun Seok Park; Soo Yeun Park; Soo Han Jun

    2012-01-01

    AIM:To access the short-term outcomes of simultaneous laparoscopic surgery combined with resection for synchronous lesions in patients with colorectal cancer.METHODS:Between March 1996 and April 2010 prospectively collected data were reviewed from 93 consecutive patients who had colorectal cancer and underwent simultaneous multiple organ resection (combined group) and 1090 patients who underwent conventional laparoscopic right hemicolectomy or laparoscopic low/anterior resection for colorectal cancer (non-combined group).In the combined group,there were nine gastric resections,three nephrectomies,nine adrenalectomies,56 cholecystectomies,and 21 gynecologic resections.In addition,five patients underwent simultaneous laparoscopic resection for three organs.The patient demographics,intra-operative outcomes,surgical morbidity,and short-term outcomes were compared between the two groups (the combined and non-combined groups).RESULTS:There were no significant differences in the clinicopathological variables between the two groups.The operating time was significantly longer in the combined group than in the non-combined group,regardless of tumor location (laparoscopic right hemicolectomy and laparoscopic low/anterior resection groups; P =0.048 and P < 0.001,respectively).The other intraoperative outcomes,such as the complications and open conversion rate,were similar in both groups.The rate of post-operative morbidity in the combined group was similar to the non-combined group (combined vs non-combined,15.1% vs 13.5%,P =0.667).Oncological safety for the colon and synchronous lesions were obtained in the combined group.CONCLUSION:Simultaneous laparoscopic multiple organ resection combined with colorectal cancer is a safe and feasible option in selected patients.

  4. Combined precut in difficult biliary cannulation

    Directory of Open Access Journals (Sweden)

    Jesús Espinel-Díez

    2013-06-01

    Full Text Available Aim: precut sphincterotomy refers to a variety of endoscopic techniques that are used in order to access the bile duct when conventional methods of cannulation have failed. There are not significant data (such as efficacy, safety about the use of different techniques of precutting at the same session. We have described our experience with combined precut sphincterotomy (CPS and we have compared our results to the use of an isolated precut. Patients and methods: we have performed 247 precuts of a total of 2.390 ERCPs. Patients were distributed according to the type of precut practiced: Needle-knife, transpancreatic and combined precut sphincterotomies. "Combined precut" consisted in performing first a transpancreatic sphincterotomy and, if the access was not achieved, then performing a needle-knife sphincterotomy in the same session. The data about safety and efficacy were prospectively collected. The complications were defined according to the consensus criteria. Results: we performed precutting techniques in 247 patients. Needle-knife, transpancreatic, and combined precuts were performed in 125 (6.9%, 74 (4.1% and 48 (2.6% patients, respectively. Bile duct cannulation was successful in 48 patients (100% in the group of combined precut, 121 patients (96.8% in the transpancreatic group, and 67 patients (90.5% in the needle-knife group (p = 0.03. There were not differences in complications rates between the three groups. There was no pancreatitis in the combined precut group. The complications were successfully managed with conservative treatment. Conclusions: combined precut sphincterotomy seems to be a safe and successful technique in those cases of difficult bile duct cannulation.

  5. A cost-minimization analysis of combination therapy in hypertension: fixed-dose vs extemporary combinations

    Directory of Open Access Journals (Sweden)

    Marco Bellone

    2013-12-01

    Full Text Available BACKGROUND: Cardiovascular disease management and prevention represent the leading cost driver in Italian healthcare expenditure. In order to reach the target blood pressure, a large majority of patients require simultaneous administration of multiple antihypertensive agents.OBJECTIVE: To assess the economic impact of the use of fixed dose combinations of antihypertensive agents, compared to the extemporary combination of the same principles.METHODS: A cost minimization analysis was conducted to determine the pharmaceutical daily cost of five fixed dose combinations (olmesartan 20 mg + amlodipine 5 mg, perindopril 5 mg + amlodipine 5 mg, enalapril 20 mg + lercanidipine 10 mg, felodipine 5 mg + ramipril 5 mg, and delapril 30 mg + manidipine 10 mg compared with extemporary combination of the same principles in the perspective of the Italian NHS. Daily acquisition costs are estimated based on current Italian prices and tariffs.RESULTS: In three cases the use of fixed‑dose combination instead of extemporary combination induces a lower daily cost. Fixed combination treatment with delapril 30 mg + manidipine 10 mg induces greater cost savings for the National Health System (95,47 €/pts/year, as compared to free drugs combination therapy.CONCLUSIONS: Compared with free drug combinations, fixed‑dose combinations of antihypertensive agents are associated with lower daily National Health Service acquisition costs.http://dx.doi.org/10.7175/fe.v14i4.886

  6. Amodiaquine and Ciprofloxacin Combination in Plasmodiasis Therapy

    Directory of Open Access Journals (Sweden)

    Peace Mayen Edwin Ubulom

    2015-01-01

    Full Text Available Objective. The study was designed to determine the efficacy of combined Amodiaquine and Ciprofloxacin in plasmodiasis therapy. Method. The in vivo antiplasmodial effect of different dosage levels of Amodiaquine, Ciprofloxacin, and their combinations against Plasmodium berghei berghei was evaluated using Swiss albino mice. Results. Amodiaquine (a known antiplasmodial agent had a fairly significant antiplasmodial effect reducing the parasites for every 100 red blood cells (RBC from 66 to 16 (75.75% at the tolerable dosage level of 7.5 mg/kg body weight while Ciprofloxacin (an antibiotic known to have antimalarial effect showed an insignificant antiplasmodial effect reducing the parasites for every 100 RBC from 65 to 64 (1.53% at the tolerable dosage level of 10.7 mg/kg body weight. Conversely, the combination therapy of Amodiaquine and Ciprofloxacin had a significant antiplasmodial effect at all the doses administered. The combination of 7.5 mg/kg of Amodiaquine and 12.8 mg/kg of Ciprofloxacin, however, showed the most significant antiplasmodial effect of the doses used reducing the number of parasites per 100 RBC from 60 to 10 (83.33%. Conclusions. Appropriate Amodiaquine and Ciprofloxacin combination will be effective for the treatment of malaria and better than either Amodiaquine or Ciprofloxacin singly at their recommended dosage levels.

  7. Amodiaquine and Ciprofloxacin Combination in Plasmodiasis Therapy.

    Science.gov (United States)

    Ubulom, Peace Mayen Edwin; Udobi, Chinweizu Ejikeme; Madu, Mark Iheukwumere

    2015-01-01

    Objective. The study was designed to determine the efficacy of combined Amodiaquine and Ciprofloxacin in plasmodiasis therapy. Method. The in vivo antiplasmodial effect of different dosage levels of Amodiaquine, Ciprofloxacin, and their combinations against Plasmodium berghei berghei was evaluated using Swiss albino mice. Results. Amodiaquine (a known antiplasmodial agent) had a fairly significant antiplasmodial effect reducing the parasites for every 100 red blood cells (RBC) from 66 to 16 (75.75%) at the tolerable dosage level of 7.5 mg/kg body weight while Ciprofloxacin (an antibiotic known to have antimalarial effect) showed an insignificant antiplasmodial effect reducing the parasites for every 100 RBC from 65 to 64 (1.53%) at the tolerable dosage level of 10.7 mg/kg body weight. Conversely, the combination therapy of Amodiaquine and Ciprofloxacin had a significant antiplasmodial effect at all the doses administered. The combination of 7.5 mg/kg of Amodiaquine and 12.8 mg/kg of Ciprofloxacin, however, showed the most significant antiplasmodial effect of the doses used reducing the number of parasites per 100 RBC from 60 to 10 (83.33%). Conclusions. Appropriate Amodiaquine and Ciprofloxacin combination will be effective for the treatment of malaria and better than either Amodiaquine or Ciprofloxacin singly at their recommended dosage levels.

  8. Energy Analysis in Combined Reforming of Propane

    Directory of Open Access Journals (Sweden)

    K. Moon

    2013-01-01

    Full Text Available Combined (steam and CO2 reforming is one of the methods to produce syngas for different applications. An energy requirement analysis of steam reforming to dry reforming with intermediate steps of steam reduction and equivalent CO2 addition to the feed fuel for syngas generation has been done to identify condition for optimum process operation. Thermodynamic equilibrium data for combined reforming was generated for temperature range of 400–1000°C at 1 bar pressure and combined oxidant (CO2 + H2O stream to propane (fuel ratio of 3, 6, and 9 by employing the Gibbs free energy minimization algorithm of HSC Chemistry software 5.1. Total energy requirement including preheating and reaction enthalpy calculations were done using the equilibrium product composition. Carbon and methane formation was significantly reduced in combined reforming than pure dry reforming, while the energy requirements were lower than pure steam reforming. Temperatures of minimum energy requirement were found in the data analysis of combined reforming which were optimum for the process.

  9. A combined cycle engine test facility

    Energy Technology Data Exchange (ETDEWEB)

    Engers, R.; Cresci, D.; Tsai, C. [General Applied Science Laboratories Inc., Ronkonkoma, NY (United States)

    1995-09-01

    Rocket-Based Combined-Cycle (RBCC) engines intended for missiles and/or space launch applications incorporate features of rocket propulsion systems operating in concert with airbreathing engine cycles. Performance evaluation of these types of engines, which are intended to operate from static sea level take-off to supersonic cruise or accerlerate to orbit, requires ground test capabilities which integrate rocket component testing with airbreathing engine testing. A combined cycle engine test facility has been constructed in the General Applied Science Laboratories, Inc. (GASL) Aeropropulsion Test Laboratory to meet this requirement. The facility was designed to support the development of an innovative combined cycle engine concept which features a rocket based ramjet combustor. The test requirements included the ability to conduct tests in which the propulsive force was generated by rocket only, the ramjet only and simultaneous rocket and ramjet power (combined cycle) to evaluate combustor operation over the entire engine cycle. The test facility provides simulation over the flight Mach number range of 0 to 8 and at various trajectories. The capabilities of the combined cycle engine test facility are presented.

  10. CHARACTERISTIC OF ECONOMIC ASSESSMENT OF COMBINE HARVESTERS

    Directory of Open Access Journals (Sweden)

    Bershickiy Y. I.

    2015-09-01

    Full Text Available We have highlighted the importance of ensuring a rational nomenclative and quantity structure of agricultural equipment for the timely and quality harvest of grain and cereal crops in agricultural organizations in southern Russia. The article shows the difficulty of choosing a certain trademark of combine harvester for the acquisition of a variety of domestic and foreign farm machine that implemented in the domestic market of agricultural machinery. We have considered different directions of price and operating characteristic of a combine harvester made by different manufacturers. We have also proved the exclusively importance and need for correct comparative economic assessment in conditions abatement of the national currency rate and a prices increase for imported equipment of mechanization, revealed methodical characteristic of technologic and economic evaluation of harvesting equipment, based on the calculation of unit (1 hectare harvest area of aggregate costs, including the costs of exploitation a combine and additional costs caused to losses crops in the process of harvesting as design features of the machines. Comparative economic analysis of the most sold combine harvesters made by domestic and foreign manufacturers in the Russian market was carried out. We have proved the economic efficiency of the acquisition of domestic combine harvesters under current assessment at correlation prices for domestic and imported equipment of mechanization

  11. Multivariate search for differentially expressed gene combinations

    Directory of Open Access Journals (Sweden)

    Klebanov Lev

    2004-10-01

    Full Text Available Abstract Background To identify differentially expressed genes, it is standard practice to test a two-sample hypothesis for each gene with a proper adjustment for multiple testing. Such tests are essentially univariate and disregard the multidimensional structure of microarray data. A more general two-sample hypothesis is formulated in terms of the joint distribution of any sub-vector of expression signals. Results By building on an earlier proposed multivariate test statistic, we propose a new algorithm for identifying differentially expressed gene combinations. The algorithm includes an improved random search procedure designed to generate candidate gene combinations of a given size. Cross-validation is used to provide replication stability of the search procedure. A permutation two-sample test is used for significance testing. We design a multiple testing procedure to control the family-wise error rate (FWER when selecting significant combinations of genes that result from a successive selection procedure. A target set of genes is composed of all significant combinations selected via random search. Conclusions A new algorithm has been developed to identify differentially expressed gene combinations. The performance of the proposed search-and-testing procedure has been evaluated by computer simulations and analysis of replicated Affymetrix gene array data on age-related changes in gene expression in the inner ear of CBA mice.

  12. On the Combination Procedure of Correlated Errors

    CERN Document Server

    Erler, Jens

    2015-01-01

    When averages of different experimental determinations of the same quantity are computed, each with statistical and systematic error components, then frequently the statistical and systematic components of the combined error are quoted explicitly. These are important pieces of information since statistical errors scale differently and often more favorably with the sample size than most systematical or theoretical errors. In this communication we describe a transparent procedure by which the statistical and systematic error components of the combination uncertainty can be obtained. We develop a general method and derive a general formula for the case of Gaussian errors with or without correlations. The method can easily be applied to other error distributions, as well. For the case of two measurements, we also define disparity and misalignment angles, and discuss their relation to the combination weight factors.

  13. On the combination procedure of correlated errors

    Energy Technology Data Exchange (ETDEWEB)

    Erler, Jens [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Mexico D.F. (Mexico)

    2015-09-15

    When averages of different experimental determinations of the same quantity are computed, each with statistical and systematic error components, then frequently the statistical and systematic components of the combined error are quoted explicitly. These are important pieces of information since statistical errors scale differently and often more favorably with the sample size than most systematical or theoretical errors. In this communication we describe a transparent procedure by which the statistical and systematic error components of the combination uncertainty can be obtained. We develop a general method and derive a general formula for the case of Gaussian errors with or without correlations. The method can easily be applied to other error distributions, as well. For the case of two measurements, we also define disparity and misalignment angles, and discuss their relation to the combination weight factors. (orig.)

  14. Generating Combinations by Three Basic Operations

    Institute of Scientific and Technical Information of China (English)

    Yong-xi Cheng

    2007-01-01

    We investigate the problem of listing combinations using a special class of operations, prefix shifts. Com- binations are represented as bitstrings of O's and l's, and prefix shifts are the operations of rotating some prefix of a bitstring by one position to left or right. We give a negative answer to an open problem asked by F. Ruskey and A. Williams (Generating combinations by prefix shifts, In Proc. Llth Annual International Computing and Combinatorics Conference 2005, LNCS 3595, Springer, 2005, pp.570~576), that is whether we can generate combinations by only using three very basic prefix shifts on bitstrings, which are transposition of the first two bits and the rotation of the entire bitstring by one position in either direction (I.e., applying the permutations σ2, σn and σn1- to the indices of the bitstrings).

  15. A universal combination treatment for vaginitis.

    Science.gov (United States)

    Bornstein, Jacob; Zarfati, Doron

    2008-01-01

    We compared a novel vaginal tablet consisting of 100 mg of clotrimazole and 100 mg of metronidazole ('Clo-Met') to a 100-mg clotrimazole tablet in the treatment of vaginitis. A multicenter, double-blind, randomized controlled study. Women with vaginal discharge and diagnosed as suffering from vaginitis caused by Trichomonas vaginalis, bacterial vaginosis or Candida albicans, or any combination of the three, and who had not received treatment for vaginitis during the previous month, were studied. 165 patients were enrolled into the study--84 into the combined therapy group, and 81 into the clotrimazole group. In women with Candida vaginitis, Clo-Met was more effective than clotrimazole treatment (p vaginal tablet consisting of clotrimazole and metronidazole is therapeutically effective in candidal vaginitis. The effectiveness of Clo-Met on bacterial vaginosis, T. vaginalis infection as well as on vaginal infections due to a combination of these microorganisms should be studied further.

  16. Combination of measurements and the BLUE method

    CERN Document Server

    Lista, Luca

    2016-01-01

    The most accurate method to combine measurement from different experiments is to build a combined likelihood function and use it to perform the desired inference. This is not always possible for various reasons, hence approximate methods are often convenient. Among those, the best linear unbiased estimator (BLUE) is the most popular, allowing to take into account individual uncertainties and their correlations. The method is unbiased by construction if the true uncertainties and their correlations are known, but it may exhibit a bias if uncertainty estimates are used in place of the true ones, in particular if those estimated uncertainties depend on measured values. In those cases, an iterative application of the BLUE method may reduce the bias of the combined measurement.

  17. Combining abilities of silage maize grain yield

    Directory of Open Access Journals (Sweden)

    Živanović Tomislav

    2005-01-01

    Full Text Available The aim of the present study was to evaluate the following parameters of maize grain yield: variability of inbred lines and their diallel hybrids superior-parent heterosis and general and special combining abilities. According to obtained results of the two-year study, it can be concluded that variability of this trait is significantly affected by a genotype, year and their interaction. As expected, hybrids had higher average grain yields than inbreds due to the depression of this trait that occurs in inbreds during inbreeding. The highest average value of heterosis for gain yield was detected in the hybrid ZPLB405 x ZPLB406 (123.0% and 178.1% in 1997 and 1998, respectively. The estimation of combining abilities was done on the basis of diallel hybrids after the method established by Griffing, 1956 (method II, mathematical model I. The analysis of variance of combining ability for grain yield indicated highly significant values of GCA and SCA for the observed trait in both study years. Grain yield inheritance was more affected by non-additive genes (dominance and epistasis as indicated by the GCA to SCA ratio that was smaller than unity. The inbreds ZPLB401 and ZPLB406 had high GCA effects, while the hybrid combinations ZPLB40Î x ZPLB402, ZPLB401 x ZPLB403, ZPLB401 x ZPLB405, ZPLB402 x ZPLB406, ZPLB403 x ZPLB406, ZPLB404 x ZPLB406, ZPLB405 x ZPLB406 had high SCA effects in both study years. These hybrid combinations include one parent with high GCA effects and other with low GCA effects. Furthermore, there are combinations ZPLB402 x ZPLB405, ZPLB403 x ZPLB405 and ZPLB404 x ZPLB405 with significant SCA effects that include parents with low GCA effects. This is probably the result of the additive type (additive x additive of interaction between parents.

  18. Optimizing neurotrophic factor combinations for neurite outgrowth

    Science.gov (United States)

    Deister, C.; Schmidt, C. E.

    2006-06-01

    Most neurotrophic factors are members of one of three families: the neurotrophins, the glial cell-line derived neurotrophic factor family ligands (GFLs) and the neuropoietic cytokines. Each family activates distinct but overlapping cellular pathways. Several studies have shown additive or synergistic interactions between neurotrophic factors from different families, though generally only a single combination has been studied. Because of possible interactions between the neurotrophic factors, the optimum concentration of a factor in a mixture may differ from the optimum when applied individually. Additionally, the effect of combinations of neurotrophic factors from each of the three families on neurite extension is unclear. This study examines the effects of several combinations of the neurotrophin nerve growth factor (NGF), the GFL glial cell-line derived neurotrophic factor (GDNF) and the neuropoietic cytokine ciliary neurotrophic factor (CNTF) on neurite outgrowth from young rat dorsal root ganglion (DRG) explants. The combination of 50 ng ml-1 NGF and 10 ng ml-1 of each GDNF and CNTF induced the highest level of neurite outgrowth at a 752 ± 53% increase over untreated DRGs and increased the longest neurite length to 2031 ± 97 µm compared to 916 ± 64 µm for untreated DRGs. The optimum concentrations of the three factors applied in combination corresponded to the optimum concentration of each factor when applied individually. These results indicate that the efficacy of future therapies for nerve repair would be enhanced by the controlled release of a combination of neurotrophins, GFLs and neuropoietic cytokines at higher concentrations than used in previous conduit designs.

  19. Efficient power combiner for THz radiation

    Directory of Open Access Journals (Sweden)

    Hamide Seidfaraji

    2016-08-01

    Full Text Available Most dangerous explosive materials, both toxic and radioactive, contain nitrogen salts with resonant absorption lines in the frequency range 0.3-10 THz. Therefore, there has been growing interest in remotely detecting such materials by observing the spectrum of reflected signals when the suspicious material is interrogated by THz radiation. Practical portable THz sources available today generate only 20–40 mW output power. This power level is too low to interrogate suspicious material from a safe distance, especially if the material is concealed. Hence, there is a need for sources that can provide greater power in the THz spectrum. Generating and extracting high output power from THz sources is complicated and inefficient. The efficiency of vacuum electronic microwave sources is very low when scaled to the THz range and THz sources based on scaling down semiconductor laser sources have low efficiency as well, resulting in the well known “THz gap.” The reason for such low efficiencies for both source types is material losses in the THz band. In this article an efficient power combiner is described that is based on scaling to higher frequencies a microwave combiner that increases the output power in the THz range of interest in simulation studies. The proposed power combiner not only combines the THz power output from several sources, but can also form a Gaussian wavebeam output. A minimum conversion efficiency of 89% with cophased inputs in a lossy copper power combiner and maximum efficiency of 100% in a Perfect Electric Conductor (PEC-made power combiner were achieved in simulations. Also, it is shown that the TE01 output mode is a reasonable option for THz applications due to the fact that conductive loss decreases for this mode as frequency increases.

  20. Wind turbine blade testing under combined loading

    DEFF Research Database (Denmark)

    Roczek-Sieradzan, Agnieszka; Nielsen, Magda; Branner, Kim;

    2011-01-01

    The paper presents full-scale blade tests under a combined flap- and edgewise loading. The main aim of this paper is to present the results from testing a wind turbine blade under such conditions and to study the structural behavior of the blade subjected to combined loading. A loading method using...... anchor plates was applied, allowing transverse shear distortion. The global and local deformation of the blade as well as the reproducibility of the test was studied and the results from the investigations are presented....

  1. Combining seismology and spectropolarimetry of hot stars

    CERN Document Server

    Neiner, Coralie; Mathis, Stéphane; Degroote, Pieter

    2014-01-01

    Asteroseismology and spectropolarimetry have allowed us to progress significantly in our understanding of the physics of hot stars over the last decade. It is now possible to combine these two techniques to learn even more information about hot stars and constrain their models. While only a few magnetic pulsating hot stars are known as of today and have been studied with both seismology and spectropolarimetry, new opportunities - in particular Kepler2 and BRITE - are emerging and will allow us to rapidly obtain new combined results.

  2. Combined algebraic and multiplicative properties near zero

    CERN Document Server

    De, Dibyendu

    2012-01-01

    It was proved that whenever $\\mathbb{N}$ is partitioned into finitely many cells, one cell must contain arbitrary length arithmetic and geometric progression nicely intertwined, so that one cell must be rich in the sense of containing substantial combined additive and multiplicative properties. Further it is known that IP$^*$ and central$^*$ sets are also rich in substantial combined additive and multiplicative properties but not partition regular. In this article we prove that these types of results also hold near zero for dense subsemigroups $S$ of $((0,\\infty),+)$ for which $(S\\cap(0,1),\\cdot)$.

  3. Combined air and water pollution control system

    Science.gov (United States)

    Wolverton, Billy C. (Inventor); Jarrell, Lamont (Inventor)

    1990-01-01

    A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

  4. PANSAID - PAracetamol and NSAID in combination

    DEFF Research Database (Denmark)

    Thybo, Kasper Højgaard; Hägi-Pedersen, Daniel; Wetterslev, Jørn

    2017-01-01

    BACKGROUND: Effective postoperative pain management is essential for the rehabilitation of the surgical patient. No 'gold standard' exists after total hip arthroplasty (THA) and combinations of different nonopioid medications are used with virtually no evidence for additional analgesic efficacy...... compared to monotherapy. The objective of this trial is to investigate the analgesic effects and safety of paracetamol and ibuprofen alone and in combination in different dosages after THA. METHODS: PANSAID is a placebo-controlled, parallel four-group, multicentre trial with centralised computer...

  5. Combined treatment for complex intracranial aneurysm

    Directory of Open Access Journals (Sweden)

    Chiriac A.

    2015-06-01

    Full Text Available Complex aneurysms often cannot be completely excluded by a single approaches. Today successful treatment of these lesions requires a combination between microsurgical and endovascular techniques. Planning of combined treatment require a very good understanding of aneurysm anatomy and a close collaboration between neurosurgeon and neuroendovascular interventionist. Endovascular coiling can usually be used as early treatment for a partially aneurysm occlusion including the ruptured area and followed by definitive clipping. On the other hand microsurgical clipping also can be used as first treatment for complex aneurysm neck reconstruction, allowing successful secondary placement of coils inside the remnant aneurysm sac

  6. Maximisation of Combined Cycle Power Plant Efficiency

    Directory of Open Access Journals (Sweden)

    Janusz Kotowicz

    2015-12-01

    Full Text Available The paper presents concepts for increasing the efficiency of a modern combined cycle power plant. Improvement of gas turbine performance indicators as well as recovering heat from the air cooling the gas turbine’s flow system enable reaching gross electrical efficiencies of around 65%. Analyses for a wide range of compressor pressure ratios were performed. Operating characteristics were developed for the analysed combined cycle plant, for different types of open air cooling arrangements of the gas turbine’s expander: convective, transpiration and film.

  7. On combining significances. Some trivial examples

    CERN Document Server

    Krasnikov, N V

    2010-01-01

    For Poisson distribution $Pois(n, \\lambda)$ with $\\lambda \\gg 1$, $n \\gg 1$ we propose to determine significance as $S = \\frac{n_{obs}-\\lambda}{\\sqrt{\\lambda}}$. The significance $S$ coincides up to sign with often used significance. For experiments which measure the same quantities the natural but not unique rule for significance combining is $S_{comb}(S_1, S_2) = \\frac{S_1\\sigma_1+S_2\\sigma_2}{\\sqrt{\\sigma^2_1+\\sigma^2_2}}$, where $\\sigma_1$ and $\\sigma_2$ are variations. We also propose the rule for significances combining for the case with systematic errors.

  8. [Combined treatment: regimens, indications and safety profile].

    Science.gov (United States)

    Muñiz Grijalvo, Ovidio; Villar Ortiz, Jose

    2013-01-01

    Statins are the current basis of lipid-lowering therapy, despite which may have limitations on efficacy and safety. In high risk patients who do not achieve current lipid goals, in those intolerant to statins or those with atherogenic dyslipidemia, it is possible combine two or more lipid lowering drugs, including statins, ezetimibe, bile acid sequestrants, fibrates, niacin and prescription omega-3 fatty acids. However, for most of these combination therapies pivotal data on clinical outcomes are still lacking. Copyright © 2013 Elsevier España, S.L. and SEA. All rights reserved.

  9. INCREASING COMBINATIONAL CIRCUIT PERFORMANCE VIA PIPELINING

    Directory of Open Access Journals (Sweden)

    Yu. V. Pottosin

    2013-01-01

    Full Text Available The question of increasing performance of a device with no memory, which develops a sequence of discrete signals, is considered. A problem is set to divide a given multilevel combinational circuit into a given number of cascades with registers providing pipeline-wise development of incoming signals. To solve this problem we use a model based on representation of combinational circuit as a directed graph. In the process of solving this problem, the frequency of incoming signals is established. This frequency must be as high as possible.

  10. Combined GMSK Communications and PN Ranging

    Science.gov (United States)

    Orr, Richard; Divsalar, Dariush

    2008-01-01

    A document discusses a method by which GMSK (Gaussian minimum shift keying) modulation and a pseudonoise (PN) ranging signal may be combined. By isolating the in-phase and quadrature components after carrier lock, and extracting their low-pass and band-pass filtered components, there is enough information available to both demodulate data and track the PN signal. The proposed combined GMSK communications and PN ranging is one potential approach to address emerging requirements for simultaneous high data rate communications from and tracking of vehicles in deep space or at the Moon.

  11. FAST CORRELATION ATTACKS ON BLUETOOTH COMBINER

    Institute of Scientific and Technical Information of China (English)

    Ma Weiju; Feng Dengguo

    2006-01-01

    A simple fast correlation attack is used to analysis the security of Bluetooth combiner in this paper.This attack solves the tradeoff between the length of the keystream and the computing complexity needed to recover the secret key. We give the computing complexities of the attack algorithm according to different lengths of the known keystream. The result is less time-consuming than before. It is also shown that the security of the modified Bluetooth combiner by Hermelin and Nyberg is not significantly enhanced.

  12. 75 FR 17138 - Combined Notice of Filings

    Science.gov (United States)

    2010-04-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings March 26, 2010. Take notice that the Commission... Gas Transmission, LLC submits Eleventh Revised Sheet 4G.02 to its FERC Gas Tariff, Fourth...

  13. 75 FR 32935 - Combined Notice of Filings

    Science.gov (United States)

    2010-06-10

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings June 1, 2010. Take notice that the...: Kinder Morgan Interstate Gas Transmission LLC submits Twenty-seventh Revised Sheet No 4G.01 to its...

  14. 75 FR 1764 - Combined Notice of Filings

    Science.gov (United States)

    2010-01-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings January 4, 2010. Take notice that the Commission... Revised Sheet 4G.01 et al. to FERC Gas Tariff, Fourth Revised Volume 1A, to be effective 1/1/10....

  15. Asymptotic Distributions for Tests of Combined Significance.

    Science.gov (United States)

    Becker, Betsy Jane

    This paper discusses distribution theory and power computations for four common "tests of combined significance." These tests are calculated using one-sided sample probabilities or p values from independent studies (or hypothesis tests), and provide an overall significance level for the series of results. Noncentral asymptotic sampling…

  16. Isolepis tenella, a New Combination in Cyperaceae

    NARCIS (Netherlands)

    Muthama Muasya, A.; Simpson, D.; Smets, E.

    2006-01-01

    Since the publication of a monograph on Isolepis (Cyperaceae) in 2002, further data on the genus have been collected, necessitating additional nomenclatural change. Isolepis is a predominantly southern hemisphere genus with high species diversity in South Africa and Australia. A new combination is m

  17. Chasing megawatts in combined cycle plants

    Energy Technology Data Exchange (ETDEWEB)

    Koch, J. [Power Plant Performance Specialist, Lansdowne, PA (United States); DeGeeter, S. [Ocean State Power, Harrisville, RI (United States); Haynes, C.J. [New England Power Co., Somerset, MA (United States)

    1996-05-01

    Combined cycle owners do not have to accept that combined cycle performance must degrade over time. Through low cost testing using existing instrumentation, a method is presented to identify causes for lost generation. A 500 MW combined cycle plant, with two STAG 207EA units, had lost 17 MW since initial operation, and found that: Gas side fouling on A four HRSG`s accounted for 8 MW of the total loss LP steam turbine efficiency was below design on one unit, contributing 3 MW Condenser air removal was poor on both units, a loss of an additional 2 MW Compressor and turbine section efficiency losses on 2 of 4 GT`s cost over 4 MW The test also revealed that the other two GT`s, both cooling towers, and one of the two steam turbines, were performing at or near design. Thus far 3 MW has been recovered, with planning underway for recovery of another 3 MW. The remaining 11 MW, though not immediately recoverable, will be the focus of planning for the next major outage. This simple method can be used at any combined cycle using existing instrumentation, with minimal intrusion on daily operations. The use of redundant measurements and uncertainty analysis assures valid and useful results.

  18. Combined PET/MR imaging in neurology

    DEFF Research Database (Denmark)

    Andersen, Flemming Littrup; Ladefoged, Claes Nøhr; Beyer, Thomas

    2014-01-01

    AIM: Combined PET/MR systems have now become available for clinical use. Given the lack of integrated standard transmission (TX) sources in these systems, attenuation and scatter correction (AC) must be performed using the available MR-images. Since bone tissue cannot easily be accounted for duri...

  19. Sensitivity of Interstitial combined Chemotherapy against Glioma

    Institute of Scientific and Technical Information of China (English)

    WANG Ming-sheng; LIN Jian-ying; ZHOU Guo-sheng; ZHANG Xin-zhong

    2006-01-01

    Objective To investigate the inhibitory effects of combination chemotherapy of Carboplatin(CBP) ,Teniposide (Vm-26) ,Methasquin(MTX),and Nimodipine(NIM) on glioma,and to explore the sensitivity of glioma cells to different treatment regimens so as to provide some clues for clinical usage of interstitial combination chemotherapy. Methods MTT assay and 3H-TdR incorporation assay were performed to evaluate the inhibitory effects upon the proliferation of glioma cells,and to compare the sensitivity of glioma cells to administration of CBP,Vm-26, MTX, and NIM with that of the administration of CBP + NIM, Vm-26 + NIM, MTX + NIM, CBP + Vm-26 + MTX, or CBP + Vm-26 + MTX + NIM respectively. Results The inhibition rate of CBP + Vm-26 + MTX + NIM combination administration against glioma cells was 96.64%,which was higher than that of CBP + NIM (69.03%), Vm-26 + NIM (71.53%), MTX + NIM (52. 75% ), CBP + Vm-26 + MTX(78.59%)(P<0.01),and the dosage of CBP,Vm-26,and MTX was declined to 1/10 ~ 1/100 that of respective use of CBP,Vm-26,and MTX. Conclusions The curative effects of combination administration of CBP,Vm-26, MTX, and NIM was much better than that of respective administration,suggesting a higher inhibition rate and a lower dosage use.

  20. Combined Heat and Power and Emissions Trading

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The aim of this IEA Information Paper is to help policy makers and other stakeholders understand the challenges facing the incorporation of high efficiency combined heat and power (CHP) into greenhouse gas (GHG) Emissions Trading Schemes (ETSs) -- and to propose options for overcoming them.

  1. 76 FR 69260 - Combined Notice of Filings

    Science.gov (United States)

    2011-11-08

    ... Transmission, LLC. Description: ConEd 2011-11-01 Release to Infinite Energy to be effective 11/1/2011. Filed... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings November 2, 2011. Take notice that the...

  2. American Holidays: Culture and Language Learning Combined.

    Science.gov (United States)

    Wylie, Grace Scott

    Suggestions for combining cultural exposure and language instruction through class activities geared to American holidays are outlined. General information about gathering holiday-related realia and instructional materials from local newspapers and magazines is provided, and four specific holidays are highlighted. For each holiday, sources of…

  3. Combining Qualitative and Quantitative Data: An Example.

    Science.gov (United States)

    Sikka, Anjoo; And Others

    Methodology from an ongoing research study to validate teaching techniques for deaf and blind students provides an example of the ways that several types of quantitative and qualitative data can be combined in analysis. Four teacher and student pairs were selected. The students were between 14 and 21 years old, had both auditory and visual…

  4. Radiotherapy versus combined modality in early stages

    DEFF Research Database (Denmark)

    Specht, L.; Carde, P.; Mauch, P.;

    1992-01-01

    In early stage Hodgkin's disease the optimal choice of treatment for the individual patient is still an unresolved issue. So far, twenty-two randomized trials of radiotherapy alone versus radiotherapy plus combination chemotherapy have been carried out worldwide. The preliminary results of a glob...

  5. Combinations of bacterial species in endodontic infections

    NARCIS (Netherlands)

    Peters, LB; Wesselink, P.R.; van Winkelhoff, AJ

    2002-01-01

    Aim This study was undertaken to investigate combinations of bacteria found in root-canal infections of teeth with periapical bone destruction without clinical signs and symptoms. Methodology Endodontic samples from 58 root canals were cultured anaerobically and microorganisms were counted and ident

  6. A Test of the Combined Effects Model.

    Science.gov (United States)

    Kimsey, William D.; And Others

    Two waves of telephone interviews with a sample of 141 voters were used in a study of political communication effects during the 1974 congressional election in the Illinois 24th Congressional District. Seven variables specified by the combined-effects model were derived from the interviews and factor analyzed. Two factors were found and…

  7. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  8. Combined treatment in punctate inner choroidopathy

    Directory of Open Access Journals (Sweden)

    Terelak-Borys B

    2016-09-01

    Full Text Available Barbara Terelak-Borys, Katarzyna Zagajewska, Irmina Jankowska-Lech, Piotr Tesla, Iwona Grabska-Liberek Department of Ophthalmology, Centre of Postgraduate Medical Education, Prof W Orlowski Clinical Hospital, Warsaw, Poland Purpose: The purpose of this study was to describe a combination treatment for choroidal neovascular (CNV membrane, secondary to punctate inner choroidopathy (PIC.Patient and methods: A 44-year-old female patient was diagnosed with PIC complicated by the development of recurrent juxtafoveal neovascular membrane. The treatment included a sequence of monotherapy regimens: systemic steroid therapy, photodynamic therapy, and intravitreal injections of vascular endothelial growth factor (VEGF inhibitor (anti-VEGF. Owing to the CNV membrane resistance to various types of monotherapy, a combination treatment consisting of local injections of steroid underneath the Tenon’s capsule and intravitreal anti-VEGF injections was used.Results: Systemic steroid therapy resulted in rapid local improvement with a very short remission period. No positive effects of photodynamic therapy were observed. Sequential anti-VEGF injections led to remission periods of several months. Permanent regression of CNV membrane was achieved following combined local application of steroid and intravitreal anti-VEGF injections.Conclusion: A combination treatment including steroid and anti-VEGF medication characterized by anti-inflammatory and antiangiogenic effects may be a very beneficial option for the treatment of recurrent CNV membrane as a complication of PIC. Keywords: punctate inner choroidopathy, neovascular membrane, anti-VEGF injections, photodynamic therapy, steroids

  9. LU's Combined Acupuncture Techniques for Diarrhea

    Institute of Scientific and Technical Information of China (English)

    LI Yan-fang; CHEN Chen; NI Zhi-zhen; ZHONG Chen; XIAO Yuan-chun

    2003-01-01

    @@ Diarrhea refers to frequent discharge of loose, even watery stool. In clinic, we used the famous acupuncturist LU Shou-yan's combined acupuncture techniques of along-against, lifting-thrusting and quickslow reinforcing and reducing to treat diarrhea. Now it is reported as follows.

  10. Cotard syndrome with catatonia: Unique combination

    Directory of Open Access Journals (Sweden)

    Aniruddha Basu

    2013-01-01

    Full Text Available Cotard syndrome is a rare psychiatric condition characterized by extreme nihilistic delusions. Catatonia though common, its combination with the Cotard syndrome is exceeding rare and more so the response with the pharmacotherapy as in our case. Since, both are found in organic conditions the importance of studying such a case is to understand the underlying neurobiologic determinants.

  11. Synergistic drug combinations improve therapeutic selectivity

    Science.gov (United States)

    Lehàr, Joseph; Krueger, Andrew S.; Avery, William; Heilbut, Adrian M.; Johansen, Lisa M.; Price, E. Roydon; Rickles, Richard J.; Short, Glenn F.; Staunton, Jane E.; Jin, Xiaowei; Lee, Margaret S.; Zimmermann, Grant R.; Borisy, Alexis A.

    2009-01-01

    Prevailing drug discovery approaches focus on compounds with molecular selectivity, inhibiting disease-relevant targets over others in vitro. However in vivo, many such agents are not therapeutically selective, either because of undesirable activity at effective doses or because the biological system responds to compensate. In theory, drug combinations should permit increased control of such complex biology, but there is a common concern that therapeutic synergy will generally be mirrored by synergistic side-effects. Here we provide evidence, from 94,110 multi-dose combination experiments representing diverse disease areas and large scale flux balance simulations of inhibited bacterial metabolism, that multi-target synergies are more specific than single agent activities to particular cellular contexts. Using an anti-inflammatory combination, we show how multi-target synergy can achieve therapeutic selectivity in animals through differential target expression. Synergistic combinations can increase the number of selective therapies using the current pharmacopeia, and offer opportunities for more precise control of biological systems. PMID:19581876

  12. Combining Phonics: Approaches for Problem Readers.

    Science.gov (United States)

    Gillis, M. K.

    1982-01-01

    A method of teaching phonics to primary grade disabled readers which combines analytic, synthetic, and linguistic methods is described. The method involves starting with sight words, starting phonics synthetically with consonants, teaching other consonants analytically, adapting linguistic methods for vowels, and encouraging the use of context.…

  13. Choosing a combined oral contraceptive pill

    OpenAIRE

    2015-01-01

    The combined oral contraceptive pill is an effective contraceptive method which can also offer other benefits. However, other contraceptive options should be discussed. If the pill is the chosen method, prescribe a pill with the lowest effective dose of oestrogen and progestogen.

  14. UV-T-RH combined environmental testing

    Science.gov (United States)

    Gonzalez, C. C.

    1986-01-01

    A combined environmental aging chamber was developed at the Jet Propulsion Laboratory (JPL). The chamber has an ultraviolet (UV) light source that can be varied between 1 to 2 suns, temperature control from -40 to +175 C, and adjustable humidity. Results from two initial aging experiments (Tedlar and amorphous silicon colar cells) were presented.

  15. Urban Runoff and Combined Sewer Overflow.

    Science.gov (United States)

    Field, Richard; Gardner, Bradford B.

    1978-01-01

    Presents a literature review of wastewater treatment, covering publications of 1976-77. This review includes areas such as: (1) urban runoff quality and quantity; (2) urban hydrology; (3) management practices; and (4) combined sewer overflows. A list of 140 references is also presented. (HM)

  16. Equivalence Checking of Hierarchical Combinational Circuits

    DEFF Research Database (Denmark)

    Williams, Poul Frederick; Hulgaard, Henrik; Andersen, Henrik Reif

    1999-01-01

    This paper presents a method for verifying that two hierarchical combinational circuits implement the same Boolean functions. The key new feature of the method is its ability to exploit the modularity of circuits to reuse results obtained from one part of the circuits in other parts. We demonstrate...... our method on large adder and multiplier circuits....

  17. Theories to be combined and contrasted

    DEFF Research Database (Denmark)

    Lindenskov, Lena; Tonnesen, Pia Beck; Weng, Peter;

    2015-01-01

    for Tidlig Matematikindsats Til Marginalgrupper). The paper tells the story of how networking strategies have informed the design of TMTM: one strategy is combining elements from the two paradigms; another strategy is contrasting elements from the paradigms. The two constructs ‘the six stages...

  18. Features in visual search combine linearly.

    Science.gov (United States)

    Pramod, R T; Arun, S P

    2014-04-08

    Single features such as line orientation and length are known to guide visual search, but relatively little is known about how multiple features combine in search. To address this question, we investigated how search for targets differing in multiple features (intensity, length, orientation) from the distracters is related to searches for targets differing in each of the individual features. We tested race models (based on reaction times) and co-activation models (based on reciprocal of reaction times) for their ability to predict multiple feature searches. Multiple feature searches were best accounted for by a co-activation model in which feature information combined linearly (r = 0.95). This result agrees with the classic finding that these features are separable i.e., subjective dissimilarity ratings sum linearly. We then replicated the classical finding that the length and width of a rectangle are integral features-in other words, they combine nonlinearly in visual search. However, to our surprise, upon including aspect ratio as an additional feature, length and width combined linearly and this model outperformed all other models. Thus, length and width of a rectangle became separable when considered together with aspect ratio. This finding predicts that searches involving shapes with identical aspect ratio should be more difficult than searches where shapes differ in aspect ratio. We confirmed this prediction on a variety of shapes. We conclude that features in visual search co-activate linearly and demonstrate for the first time that aspect ratio is a novel feature that guides visual search.

  19. How Not to Combine RC4 States

    DEFF Research Database (Denmark)

    Banik, Subhadeep; Jha, Sonu

    2015-01-01

    Over the past few years, an attractive design paradigm has emerged, that aims to produce new stream cipher designs, by combining one or more independently produced RC4 states. The ciphers so produced turn out to be faster than RC4 on any software platform, mainly because the average number...

  20. A combined Richter's and de Garengeot's hernia

    Directory of Open Access Journals (Sweden)

    Hau D. Le

    2014-01-01

    CONCLUSION: Combined de Garengeot's and Richter's hernias are rare, represent a significant diagnostic challenge, and should be repaired urgently to prevent ischemic bowel, or limit contamination if ischemia is already present. Use of computed tomography will likely lead to increased pre-operative diagnosis of this rare entity.

  1. PHARMACOECONOMIC ANALYSIS OF ANTIHYPERTENSIVE DRUG COMBINATIONS USE

    Directory of Open Access Journals (Sweden)

    E. I. Tarlovskaya

    2015-09-01

    Full Text Available Aim. To pursue pharmacoeconomic analysis of two drug combinations of ACE inhibitor (enalapril and diuretic.Material and methods. Patients with arterial hypertension degree 2 and diabetes mellitus type 2 without ischemic heart disease (n=56 were included into the study. Blood pressure (BP dynamics and cost/effectiveness ratio were evaluated.Results. In group A (fixed combination of original enalapril/hydrochlorothiazide 61% of patients achieved target BP level with initial dose, and the rest 39% of patients – with double dose. In group B (non-fixed combination of generic enalapril/indapamide 60% of patients achieved the target BP with initial dose of drugs, 33% - with double dose of ACE inhibitor, and 7% - with additional amlodipine administration. In patients of group A systolic BP (SBP reduction was 45.82±1.23 mm Hg by the 12th week vs. 40.0±0.81 mm Hg in patients of group B; diastolic BP (DBP reduction was 22.47±1.05 mm Hg and 18.76±0.70 mm Hg, respectively, by the 12th week of treatment. In the first month of treatment costs of target BP achievement was 298.62 rubles per patient in group A, and 299.50 rubles – in group B; by the 12th week of treatment – 629.45 and 631.22 rubles, respectively. Costs of SBP and DBP reduction by 1 mm Hg during 12 weeks of therapy were 13 and 27 rubles per patient, respectively, in group A, and 16 and 34 rubles per patient, respectively, in group B.Conclusion. The original fixed combination (enalapril+hydrochlorothiazide proved to be more clinically effective and more cost effective in the treatment of hypertensive patients in comparison with the non-fixed combination of generic drugs (enalapril+indapamide.

  2. PHARMACOECONOMIC ANALYSIS OF ANTIHYPERTENSIVE DRUG COMBINATIONS USE

    Directory of Open Access Journals (Sweden)

    E. I. Tarlovskaya

    2014-01-01

    Full Text Available Aim. To pursue pharmacoeconomic analysis of two drug combinations of ACE inhibitor (enalapril and diuretic.Material and methods. Patients with arterial hypertension degree 2 and diabetes mellitus type 2 without ischemic heart disease (n=56 were included into the study. Blood pressure (BP dynamics and cost/effectiveness ratio were evaluated.Results. In group A (fixed combination of original enalapril/hydrochlorothiazide 61% of patients achieved target BP level with initial dose, and the rest 39% of patients – with double dose. In group B (non-fixed combination of generic enalapril/indapamide 60% of patients achieved the target BP with initial dose of drugs, 33% - with double dose of ACE inhibitor, and 7% - with additional amlodipine administration. In patients of group A systolic BP (SBP reduction was 45.82±1.23 mm Hg by the 12th week vs. 40.0±0.81 mm Hg in patients of group B; diastolic BP (DBP reduction was 22.47±1.05 mm Hg and 18.76±0.70 mm Hg, respectively, by the 12th week of treatment. In the first month of treatment costs of target BP achievement was 298.62 rubles per patient in group A, and 299.50 rubles – in group B; by the 12th week of treatment – 629.45 and 631.22 rubles, respectively. Costs of SBP and DBP reduction by 1 mm Hg during 12 weeks of therapy were 13 and 27 rubles per patient, respectively, in group A, and 16 and 34 rubles per patient, respectively, in group B.Conclusion. The original fixed combination (enalapril+hydrochlorothiazide proved to be more clinically effective and more cost effective in the treatment of hypertensive patients in comparison with the non-fixed combination of generic drugs (enalapril+indapamide.

  3. Pegvisomant and cabergoline combination therapy in acromegaly.

    Science.gov (United States)

    Bernabeu, I; Alvarez-Escolá, C; Paniagua, A E; Lucas, T; Pavón, I; Cabezas-Agrícola, J M; Casanueva, F F; Marazuela, M

    2013-03-01

    Combination with cabergoline may offer additional benefits to acromegalic patients on pegvisomant monotherapy. We evaluated the safety and efficacy profile of this combination and investigated the determinants of response. An observational, retrospective, cross-sectional study. Fourteen acromegalic patients (9 females), who were partially resistant to somatostatin analogs and on pegvisomant monotherapy. Cabergoline was added because of the presence of persistent mildly increased IGF-I. The mean follow-up time was 18.3 ± 10.4 months. The efficacy and safety profile was assessed. The influence of clinical and biochemical characteristics on treatment efficacy was studied. IGF-I levels returned to normal in 4 patients (28%) at the end of the study. In addition, some decline in IGF-I levels was observed in a further 5 patients. The % IGF-I decreased from 158 ± 64% to 124 ± 44% (p = 0.001). The average change in IGF-I was -18 ± 27% (range -67 to +24%). Lower baseline IGF-I (p = 0.007), female gender (p = 0.013), lower body weight (p = 0.031), and higher prolactin (PRL) levels (p = 0.007) were associated with a better response to combination therapy. There were no significant severe adverse events. Significant tumour shrinkage was observed in 1 patient. Combination therapy with pegvisomant and cabergoline could provide better control of IGF-I in some patients with acromegaly. Baseline IGF-I levels, female gender, body weight, and PRL levels affect the response to this combination therapy.

  4. Towards combined global monthly gravity field solutions

    Science.gov (United States)

    Jaeggi, Adrian; Meyer, Ulrich; Beutler, Gerhard; Weigelt, Matthias; van Dam, Tonie; Mayer-Gürr, Torsten; Flury, Jakob; Flechtner, Frank; Dahle, Christoph; Lemoine, Jean-Michel; Bruinsma, Sean

    2014-05-01

    Currently, official GRACE Science Data System (SDS) monthly gravity field solutions are generated independently by the Centre for Space Research (CSR) and the German Research Centre for Geosciences (GFZ). Additional GRACE SDS monthly fields are provided by the Jet Propulsion Laboratory (JPL) for validation and outside the SDS by a number of other institutions worldwide. Although the adopted background models and processing standards have been harmonized more and more by the various processing centers during the past years, notable differences still exist and the users are more or less left alone with a decision which model to choose for their individual applications. This procedure seriously limits the accessibility of these valuable data. Combinations are well established in the area of other space geodetic techniques, such as the Global Navigation Satellite Systems (GNSS), Satellite Laser Ranging (SLR), and Very Long Baseline Interferometry (VLBI). Regularly comparing and combining space-geodetic products has tremendously increased the usefulness of the products in a wide range of disciplines and scientific applications. Therefore, we propose in a first step to mutually compare the large variety of available monthly GRACE gravity field solutions, e.g., by assessing the signal content over selected regions, by estimating the noise over the oceans, and by performing significance tests. We make the attempt to assign different solution characteristics to different processing strategies in order to identify subsets of solutions, which are based on similar processing strategies. Using these subsets we will in a second step explore ways to generate combined solutions, e.g., based on a weighted average of the individual solutions using empirical weights derived from pair-wise comparisons. We will also assess the quality of such a combined solution and discuss the potential benefits for the GRACE and GRACE-FO user community, but also address minimum processing

  5. Monitoring Biological Activity at Geothermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Peter Pryfogle

    2005-09-01

    The economic impact of microbial growth in geothermal power plants has been estimated to be as high as $500,000 annually for a 100 MWe plant. Many methods are available to monitor biological activity at these facilities; however, very few plants have any on-line monitoring program in place. Metal coupon, selective culturing (MPN), total organic carbon (TOC), adenosine triphosphate (ATP), respirometry, phospholipid fatty acid (PLFA), and denaturing gradient gel electrophoresis (DGGE) characterizations have been conducted using water samples collected from geothermal plants located in California and Utah. In addition, the on-line performance of a commercial electrochemical monitor, the BIoGEORGE?, has been evaluated during extended deployments at geothermal facilities. This report provides a review of these techniques, presents data on their application from laboratory and field studies, and discusses their value in characterizing and monitoring biological activities at geothermal power plants.

  6. Combination N-Way Power Divider/Combiner and Noninvasive Reflected Power Detection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An N-way RF/microwave power divider/combiner utilizes one input and N outputs, or conversely N inputs and one output to divide (or combine) RF/microwave power while...

  7. Further development of mathematical description for combined toxicity: A case study of lead–fluoride combination

    Directory of Open Access Journals (Sweden)

    Vladimir G. Panov

    2015-01-01

    Full Text Available In this article, we check and develop further some postulates of the theory and mathematical modeling of combined toxic effect that we proposed earlier [1]. To this end, we have analyzed the results of an experiment on rats exposed during 6 weeks to repeated intraperitoneal injections of lead acetate, sodium fluoride or both. The development of intoxication was estimated quantitatively with 54 functional, biochemical and morphometric indices. For mathematical description of the effect that lead and fluorine doses produced alone or in combination, we used a response surface regression model containing linear and cross terms (hyperbolic paraboloid. It is shown that the combination of lead and fluoride features the same 10 types of combined effect that we found previously for the lead and cadmium combination. Special attention is given to indices on which lead and fluorine produce an opposite effect.

  8. Further development of mathematical description for combined toxicity: A case study of lead-fluoride combination.

    Science.gov (United States)

    Panov, Vladimir G; Katsnelson, Boris A; Varaksin, Anatoly N; Privalova, Larisa I; Kireyeva, Ekaterina P; Sutunkova, Marina P; Valamina, Irene E; Beresneva, Olga Yu

    2015-01-01

    In this article, we check and develop further some postulates of the theory and mathematical modeling of combined toxic effect that we proposed earlier [1]. To this end, we have analyzed the results of an experiment on rats exposed during 6 weeks to repeated intraperitoneal injections of lead acetate, sodium fluoride or both. The development of intoxication was estimated quantitatively with 54 functional, biochemical and morphometric indices. For mathematical description of the effect that lead and fluorine doses produced alone or in combination, we used a response surface regression model containing linear and cross terms (hyperbolic paraboloid). It is shown that the combination of lead and fluoride features the same 10 types of combined effect that we found previously for the lead and cadmium combination. Special attention is given to indices on which lead and fluorine produce an opposite effect.

  9. Joint detection and combining schemes in MIMO-HARQ systems

    Institute of Scientific and Technical Information of China (English)

    XIE Gang; XIONG Fang; ZHAO Yi; LIU Yuan-an

    2007-01-01

    This article mainly investigates the combining schemes for hybrid automatic retransmission request (HARQ) protocols in multiple-input multiple-output (MIMO) wireless communication systems. A novel scheme, which joins MIMO detection and HARQ combining, called mid-combining, is presented in this article. Based on the position of HARQ combining, we classify the HARQ combining schemes into three types, named pre-combining, mid-combining, and post-combining. The simulation results show that mid- combining can increase the system throughput for all SNRs.

  10. A Novel in situ Trigger Combination Method

    CERN Document Server

    Buzatu, Adrian; Krumnack, Nils; Yao, Wei-Ming

    2012-01-01

    Searches for rare physics processes using particle detectors in high-luminosity colliding hadronic beam environments require the use of multi-level trigger systems to reject colossal background rates in real time. In analyses like the search for the Higgs boson, there is a need to maximize the signal acceptance by combining multiple different trigger chains when forming the offline data sample. In such statistically limited searches, datasets are often amassed over periods of several years, during which the trigger characteristics evolve and their performance can vary significantly. Reliable production cross-section measurements and upper limits must take into account a detailed understanding of the effective trigger inefficiency for every selected candidate event. We present as an example the complex situation of three trigger chains, based on missing energy and jet energy, to be combined in the context of the search for the Higgs (H) boson produced in association with a W boson at the Collider Detector at F...

  11. Estimation of combined sewer overflow discharge

    DEFF Research Database (Denmark)

    Ahm, Malte; Thorndahl, Søren Liedtke; Nielsen, Jesper Ellerbæk;

    2016-01-01

    Combined sewer overflow (CSO) structures are constructed to effectively discharge excess water during heavy rainfall, to protect the urban drainage system from hydraulic overload. Consequently, most CSO structures are not constructed according to basic hydraulic principles for ideal measurement...... weirs. It can, therefore, be a challenge to quantify the discharges from CSOs. Quantification of CSO discharges are important in relation to the increased environmental awareness of the receiving water bodies. Furthermore, CSO discharge quantification is essential for closing the rainfall-runoff mass......-balance in combined sewer catchments. A closed mass-balance is an advantage for calibration of all urban drainage models based on mass-balance principles. This study presents three different software sensor concepts based on local water level sensors, which can be used to estimate CSO discharge volumes from hydraulic...

  12. Combination radial and thrust magnetic bearing

    Science.gov (United States)

    Blumenstock, Kenneth A. (Inventor)

    2002-01-01

    A combination radial and thrust magnetic bearing is disclosed that allows for both radial and thrust axes control of an associated shaft. The combination radial and thrust magnetic bearing comprises a rotor and a stator. The rotor comprises a shaft, and first and second rotor pairs each having respective rotor elements. The stator comprises first and second stator elements and a magnet-sensor disk. In one embodiment, each stator element has a plurality of split-poles and a corresponding plurality of radial force coils and, in another embodiment, each stator element does not require thrust force coils, and radial force coils are replaced by double the plurality of coils serving as an outer member of each split-pole half.

  13. Combining resummed Higgs predictions across jet bins

    Energy Technology Data Exchange (ETDEWEB)

    Boughezal, Radja [Argonne National Laboratory, IL (United States). High Energy Physics Division; Liu, Xiaohui; Petriello, Frank [Argonne National Laboratory, IL (United States). High Energy Physics Division; Northwestern Univ., Evanston, IL (United States). Dept. of Physics and Astronomy; Tackmann, Frank J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Walsh, Jonathan R. [California Univ., Berkeley, CA (United States). Ernest Orlando Lawrence Berkeley Laboratory; California Univ., Berkeley, CA (United States). Center for Theoretical Physics

    2013-12-15

    Experimental analyses often use jet binning to distinguish between different kinematic regimes and separate contributions from background processes. To accurately model theoretical uncertainties in these measurements, a consistent description of the jet bins is required. We present a complete framework for the combination of resummed results for production processes in different exclusive jet bins, focusing on Higgs production in gluon fusion as an example. We extend the resummation of the H+1-jet cross section into the challenging low transverse momentum region, lowering the uncertainties considerably. We provide combined predictions with resummation for cross sections in the H+0-jet and H+1-jet bins, and give an improved theory covariance matrix for use in experimental studies. We estimate that the relevant theoretical uncertainties on the signal strength in the H{yields}WW{sup *} analysis are reduced by nearly a factor of 2 compared to the current value.

  14. Analysis of fractals with combined partition

    Science.gov (United States)

    Dedovich, T. G.; Tokarev, M. V.

    2016-03-01

    The space—time properties in the general theory of relativity, as well as the discreteness and non-Archimedean property of space in the quantum theory of gravitation, are discussed. It is emphasized that the properties of bodies in non-Archimedean spaces coincide with the properties of the field of P-adic numbers and fractals. It is suggested that parton showers, used for describing interactions between particles and nuclei at high energies, have a fractal structure. A mechanism of fractal formation with combined partition is considered. The modified SePaC method is offered for the analysis of such fractals. The BC, PaC, and SePaC methods for determining a fractal dimension and other fractal characteristics (numbers of levels and values of a base of forming a fractal) are considered. It is found that the SePaC method has advantages for the analysis of fractals with combined partition.

  15. On Conservation Equation Combinations and Closure Relations

    Directory of Open Access Journals (Sweden)

    William G. Gray

    2014-07-01

    Full Text Available Fundamental conservation equations for mass, momentum and energy of chemical species can be combined with thermodynamic relations to obtain secondary forms, such as conservation equations for phases, an internal energy balance and a mechanical energy balance. In fact, the forms of secondary equations are infinite and depend on the criteria used in determining which species-based equations to employ and how to combine them. If one uses these secondary forms in developing an entropy inequality to be used in formulating closure relations, care must be employed to ensure that the appropriate equations are used, or problematic results can develop for multispecies systems. We show here that the use of the fundamental forms minimizes the chance of an erroneous formulation in terms of secondary forms and also provides guidance as to which secondary forms should be used if one uses them as a starting point.

  16. Wideband unbalanced waveguide power dividers and combiners

    Energy Technology Data Exchange (ETDEWEB)

    Halligan, Matthew; McDonald, Jacob Jeremiah; Strassner, II, Bernd H.

    2016-05-17

    The various technologies presented herein relate to waveguide dividers and waveguide combiners for application in radar systems, wireless communications, etc. Waveguide dividers-combiners can be manufactured in accordance with custom dimensions, as well as in accordance with waveguide standards such that the input and output ports are of a defined dimension and have a common impedance. Various embodiments are presented which can incorporate one or more septum(s), one or more pairs of septums, an iris, an input matching region, a notch located on the input waveguide arm, waveguide arms having stepped transformer regions, etc. The various divider configurations presented herein can be utilized in high fractional bandwidth applications, e.g., a fractional bandwidth of about 30%, and RF applications in the Ka frequency band (e.g., 26.5-40 GHz).

  17. Drug Combinations: Tests and Analysis with Isoboles.

    Science.gov (United States)

    Tallarida, Ronald J

    2016-03-18

    Described in this unit are experimental and computational methods to detect and classify drug interactions. In most cases, this relates to two drugs or compounds with overtly similar effects, e.g., two analgesics or two anti-hypertensives. From the dose-response data of the individual drugs, it is possible to generate a curve, the isobole, which defines all dose combinations that are expected to yield a specified effect. The theory underlying the isobole involves the calculation of doses of drug A that are effectively equivalent to doses of drug B with that equivalence determining whether the isobole is linear or nonlinear. In either case, the isobole allows for a comparison with actual combination effects making it possible to determine whether the interaction is synergistic, additive, or sub-additive. Actual as well as illustrative data are employed to demonstrate experimental design and data analysis.

  18. Screening for severe combined immunodeficiency in neonates

    Directory of Open Access Journals (Sweden)

    Kelly BT

    2013-09-01

    Full Text Available Brian T Kelly,1 Jonathan S Tam,1 James W Verbsky,1,2 John M Routes1,2 1Department of Pediatrics, 2Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI, USA Abstract: Severe combined immunodeficiency (SCID is a rare disease that severely affects the cellular and humoral immune systems. Patients with SCID present with recurrent or severe infections and often with chronic diarrhea and failure to thrive. The disease is uniformly fatal, making early diagnosis essential. Definitive treatment is hematopoietic stem cell transplantation, with best outcomes prior to 3.5 months of age. Newborn screening for SCID using the T-cell receptor excision circle assay has revolutionized early identification of infants with SCID or severe T-cell lymphopenia. Keywords: severe combined immunodeficiency, T-cell receptor excision circle, newborn screening, primary immunodeficiency

  19. Fatal combination of moclobemide overdose and whisky.

    Science.gov (United States)

    Bleumink, G S; van Vliet, A C M; van der Tholen, A; Stricker, B H Ch

    2003-03-01

    The antidepressant moclobemide (Aurorix) is a reversible inhibitor of monoamine oxidase-A. Pure moclobemide overdose is considered to be relatively safe. Mixed drug overdoses including moclobemide are potentially lethal, especially when serotonergical drugs are involved. So far, only one fatality due to moclobemide mono-overdose has been reported. We report here on a fatality following the ingestion of a moclobemide overdose in combination with half a bottle of whisky. Although dietary restrictions during moclobemide therapy are not considered necessary, the combination of large quantities of moclobemide and tyramine-containing products seems to be lethal, probably because monoamine oxidase-A selectivity is overwhelmed after massive overdoses. Since there is no specific antidote and treatment is only symptomatic, the severity of an overdose with moclobemide must not be underestimated.

  20. Combination HIV prevention: significance, challenges, and opportunities.

    Science.gov (United States)

    Kurth, Ann E; Celum, Connie; Baeten, Jared M; Vermund, Sten H; Wasserheit, Judith N

    2011-03-01

    No single HIV prevention strategy will be sufficient to control the HIV pandemic. However, a growing number of interventions have shown promise in partially protecting against HIV transmission and acquisition, including knowledge of HIV serostatus, behavioral risk reduction, condoms, male circumcision, needle exchange, treatment of curable sexually transmitted infections, and use of systemic and topical antiretroviral medications by both HIV-infected and uninfected persons. Designing the optimal package of interventions that matches the epidemiologic profile of a target population, delivering that package at the population level, and evaluating safety, acceptability, coverage, and effectiveness, all involve methodological challenges. Nonetheless, there is an unprecedented opportunity to develop "prevention packages" that combine various arrays of evidence-based strategies, tailored to the needs of diverse subgroups and targeted to achieve high coverage for a measurable reduction in population-level HIV transmission. HIV prevention strategies that combine partially effective interventions should be scaled up and evaluated.

  1. Pneumonia in immunocompetent patients: combination antibiotic therapy.

    Science.gov (United States)

    Salva, S; Borgatta, B; Rello, J

    2014-04-01

    Pneumonia's burden is still important worldwide not only because of its high incidence and mortality, but also for the elevated costs related to it. Despite the concerted efforts to reduce the incidence of sepsis-related complications, they continue to represent a major human and economic burden. The cornerstone of sepsis management is early appropriate empiric broad spectrum antibiotics, resuscitation, and source control. The association between inappropriate use of antibiotics and increased mortality is the rationale for the use of empiric antibiotic combination therapy in critically ill patients. The aim of this manuscript was to discuss recent literature regarding the management of severe pneumonia, both community-acquired and hospital-acquired/ventilator-associated, in critically ill patients. Use of combination therapy is warranted in severe infections with shock; considerations should be made on the importance of optimal antibiotic administration and adverse reactions, thus providing guidance for a rational use of antibiotics.

  2. Suction caissons subjected to monotonic combined loading

    DEFF Research Database (Denmark)

    Penzes, P.; Jensen, M.R.; Zania, Varvara

    2016-01-01

    Suction caissons are being increasingly used as offshore foundation solutions in shallow and intermediate water depths. The convenient installation method through the application of suction has rendered this type of foundation as an attractive alternative to the more traditional monopile foundation...... for offshore wind turbines. The combined loading imposed typically to a suction caisson has led to the estimation of their bearing capacity by means of 3D failure envelopes. This study aims to analyse the behaviour of suction caissons for offshore wind turbines subjected to combined loading. Finite element...... of the constitutive soil model is examined. The failure envelopes of a single suction caisson obtained by the numerical models are in good agreement with the corresponding ones suggested by closed-form expressions....

  3. [Switching and combining strategies of antidepressant medications].

    Science.gov (United States)

    Charpeaud, Thomas; Moliere, Fanny; Bubrovszky, Maxime; Haesebaert, Frédéric; Allaïli, Najib; Bation, Rémy; Nieto, Isabel; Richieri, Raphaëlle; Saba, Ghassen; Bellivier, Frank; Bennabi, Djamila; Holtzmann, Jérôme; Camus, Vincent; Courtet, Philippe; Courvoisier, Pierre; d'Amato, Thierry; Doumy, Olivier; Garnier, Marion; Bougerol, Thierry; Lançon, Christophe; Haffen, Emmanuel; Leboyer, Marion; Llorca, Pierre-Michel; Vaiva, Guillaume; El-Hage, Wissam; Aouizerate, Bruno

    2016-03-01

    Switching antidepressant medication may be helpful in depressed patients having no benefit from the initial antidepressant treatment. Before considering switching strategy, the initial antidepressant treatment should produce no therapeutic effect after at least 4 weeks of administration at adequate dosage. Choosing an antidepressant of pharmacologically distinct profile fails to consistently demonstrate a significant superiority in terms of effectiveness over the switching to another antidepressant within the same pharmacological class. Augmenting SSRI/SNRIs with mirtazapine/mianserin has become the most recommended strategy of antidepressant combinations. Augmenting SSRI with tricyclic drugs is now a less recommended strategy of antidepressant combinations given the increased risk for the occurrence of pharmacokinetic drug-drug interactions and adverse effects.

  4. Combining ability of twelve maize populations

    Directory of Open Access Journals (Sweden)

    Vacaro Elton

    2002-01-01

    Full Text Available Genetic progress depends on germplasm quality and breeding methods. Twelve maize populations and their crosses were evaluated to estimate combining ability and potential to be included as source populations in breeding programs. Plant height, point of insertion of the first ear, number of ears per plant, number of grains per ear, root and stalk lodging and grain yield were studied in two locations in Brazil, during the 1997/98 season. Genotype sum of squares was divided into general (GCA and specific (SCA combining ability. Results indicated the existence of genetic divergence for all traits analyzed, where additive effects were predominant. The high heterosis levels observed, mainly in Xanxerê, suggested the environmental influence on the manifestation of this genetic phenomenon. Populations revealed potential to be used in breeding programs; however, those more intensively submitted to selection could provide larger genetic progress, showing the importance of population improvement for the increment of the heterosis in maize.

  5. Consensus paper: combining transcranial stimulation with neuroimaging

    DEFF Research Database (Denmark)

    Siebner, Hartwig R; Bergmann, Til O; Bestmann, Sven

    2009-01-01

    In the last decade, combined transcranial magnetic stimulation (TMS)-neuroimaging studies have greatly stimulated research in the field of TMS and neuroimaging. Here, we review how TMS can be combined with various neuroimaging techniques to investigate human brain function. When applied during...... neuroimaging (online approach), TMS can be used to test how focal cortex stimulation acutely modifies the activity and connectivity in the stimulated neuronal circuits. TMS and neuroimaging can also be separated in time (offline approach). A conditioning session of repetitive TMS (rTMS) may be used to induce...... information obtained by neuroimaging can be used to define the optimal site and time point of stimulation in a subsequent experiment in which TMS is used to probe the functional contribution of the stimulated area to a specific task. In this review, we first address some general methodologic issues that need...

  6. Combined interventional therapies of hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jun Qian; Gan-Sheng Feng; Thomas Vogl

    2003-01-01

    Hepatocellular carcinoma (HCC) is one of the most commonmalignancies in the world, responsible for an estimated one million deaths annually. It has a poor prognosis due to its rapid infiltrating growth and complicating liver cirrhosis.Surgical resection, liver transplantation and cryosurgery are considered the best curative options, achieving a high rate of complete response, especially in patients with small HCC and good residual liver function. In nonsurgery, regional interventional therapies have led to a major breakthrough in the management of unresectable HCC, which include transarterial chemoembolization (TACE), percutaneous ethanol injection (PEI), radiofrequency ablation (RFA), microwave coagulation therapy (MCT), laser-induced thermotherapy (LITT), etc. As a result of the technical development of locoregional approaches for HCC during the recent decades,the range of combined interventional therapies has been continuously extended. Most combined multimodal interventional therapies reveal their enormous advantages as compared with any single therapeutic regimen alone,and play more important roles in treating unresectable HCC.

  7. Dechlorination by combined electrochemical reduction and oxidation

    Institute of Scientific and Technical Information of China (English)

    CONG Yan-qing; WU Zu-cheng; TAN Tian-en

    2005-01-01

    Chlorophenols are typical priority pollutants listed by USEPA (U.S. Environmental Protection Agency). The removal of chlorophenol could be carried out by a combination of electrochemical reduction and oxidation method. Results showed that it was feasible to degrade contaminants containing chlorine atoms by electrochemical reduction to form phenol, which was further degraded on the anode by electrochemical oxidation. Chlorophenol removal rate was more than 90% by the combined electrochemical reduction and oxidation at current of 6 mA and pH 6. The hydrogen atom is a powerful reducing agent that reductively dechlorinates chlorophenols. The instantaneous current efficiency was calculated and the results indicated that cathodic reduction was the main contributor to the degradation of chlorophenol.

  8. Thermodynamic Analysis of Combined Cycle Power Plant

    Directory of Open Access Journals (Sweden)

    A.K.Tiwari,

    2010-04-01

    Full Text Available Air Bottoming Cycle (ABC can replace the heat recovery steam generator and the steam turbine of the conventionalcombined cycle plant. The exhaust energy of the topping gas turbine of existing combine cycle is sent to gas-air heat exchange, which heats the air in the secondary gas turbine cycle. In 1980’s the ABC was proposed as an alternative for the conventional steam bottoming cycle. In spite of the cost of reducing hardware installations it could achieve a thermal efficiency of 80%. The complete thermodynamic analysis of the system has been performed by using specially designed programme, enabling the variation of main independent variables. The result shows the gain in net work output as well as efficiency of combined cycle is 35% to 68%.

  9. Combined Spinal Epdiural Anaesthesia: Single Space Technique

    Directory of Open Access Journals (Sweden)

    Khairat Mohd, Shigufta Qazi, Showkat Hussain

    2005-10-01

    Full Text Available A study of single space combined spinal epidural (CSE block was carried out in 30 patients forlower extremity orthopaedic surgery. Hyperbaric bupivacaine (0.5% was used for subarachanoidblock and (0.25% isobaric bupivacaine was given through epidural catheter for “top-up” doses tofacilitate surgery and for postoperative analgesia. Operative conditions were described as excellentin 73.33% patients, good in 23.33% patients and fair 3.33% patients. Similarly post operativeanalgesia was excellent in 70%, good in 26.66% and fair in 3.33% cases. Intra operative complicationslike hypotension < 80mm Hg occurred in 3.33% patients and < 90 mmHg in 10% patients. No postspinal headache or neurological complications were seen. CSE anaesthesia appears to combine thereliability of spinal and the flexibility of epidural block while their drawbacks are minimized.

  10. Combined additive manufacturing approaches in tissue engineering.

    Science.gov (United States)

    Giannitelli, S M; Mozetic, P; Trombetta, M; Rainer, A

    2015-09-01

    Advances introduced by additive manufacturing (AM) have significantly improved the control over the microarchitecture of scaffolds for tissue engineering. This has led to the flourishing of research works addressing the optimization of AM scaffolds microarchitecture to optimally trade-off between conflicting requirements (e.g. mechanical stiffness and porosity level). A fascinating trend concerns the integration of AM with other scaffold fabrication methods (i.e. "combined" AM), leading to hybrid architectures with complementary structural features. Although this innovative approach is still at its beginning, significant results have been achieved in terms of improved biological response to the scaffold, especially targeting the regeneration of complex tissues. This review paper reports the state of the art in the field of combined AM, posing the accent on recent trends, challenges, and future perspectives.

  11. Combined spinal intramedullary arteriovenous malformation and lipomyelomeningocele

    Energy Technology Data Exchange (ETDEWEB)

    Weon, Y.C.; Roh, H.G.; Byun, H.S. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology, Seoul (Korea); Chung, J.I. [Medimoa Hospital, Department of Radiology, Seoul (Korea); Eoh, W. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea)

    2005-10-01

    Combined spinal arteriovenous malformation and lipomyelomeningocele are extremely rare. We present a rare combined case of a lipomyelomeningocele with an intramedullary arteriovenous malformation (AVM) occurred at the L3-L4 level in a 30-year-old man who suffered from low back pain radiating to the lower extremities, dysuria, and frequency for 5 years. The MR studies showed an intradural mass with high-signal intensity on both T1-weighted and T2-weighted images, intermingled with multiple signal-void structures. The mass extended extradurally toward a subcutaneously forming fatty mass on the patient's back. Spinal angiography showed an AVM supplied by the radiculopial branches of the lumbar arteries and drained by tortuous, dilated, perimedullary veins. Endovascular embolization and surgical resection were performed. (orig.)

  12. Solids separation efficiency of combined sewer overflows.

    Science.gov (United States)

    Luyckx, G; Vaes, G; Berlamont, J

    2005-01-01

    The removal of sewer solids at combined sewer overflow locations depends on the flow patterns inside the overflow structure on the one hand and on the sediment characteristics on the other hand. Flow conditions can be described by the residence time distribution; sewer sediments can be characterised by their settling velocity distribution. The combination of both distributions leads to a dimensionless efficiency curve, which gives the removal efficiency as a function of the Hazen number. For field conditions this efficiency curve is mainly influenced by the settling velocity distribution of the sewer sediments and, as a consequence, nearly identical efficiency curves are found for different types of prototype CSO structure. For design purposes, a methodology using return frequency analysis is proposed.

  13. Combined Heavy Metal Pollution in Red Soil

    Institute of Scientific and Technical Information of China (English)

    CHENHUAIMAN; ZHENGCHNURONG

    1996-01-01

    The effects of combined heavy metal pollution of red soil on the growth of wetland rice and the transfer of Pb,Cd,Cu and Zn from soil into plants were sudied by greenhouse pot experiment,The results showed that the plantyields were markedly affected by heavy metals,with the exception of Pb,in soils under the experimental conditions,without taking into consideration all the interactions among the elements.The concentrations of the elemets in plants were mainly affected by the specific element added to the soil.The effect of interactions among the heavy metals was very significant either on plant yields or on the concentration of the elements in plants.The risk assessment of a combined pollution by heavy metals in the soil is discussed preliminarily in terms of the relative pollution equivalent.

  14. Combining cluster number counts and galaxy clustering

    CERN Document Server

    Lacasa, Fabien

    2016-01-01

    We present a detailed modelling of the joint covariance matrix between cluster number counts and the galaxy angular power spectrum. To this end, we use a Halo Model framework complemented by a Halo Occupation Distribution model (HOD), and we work in full-sky. We demonstrate the importance of accounting for non-Gaussianity to produce accurate covariance predictions, as the Gaussian part of the covariance can in fact become subdominant in certain configurations. We discuss in particular the case of the super-sample covariance (SSC), including the effects of galaxy shot-noise, halo second order bias and non-local bias, and demonstrating interesting mathematical properties. Using the joint covariance matrix and a Fisher matrix methodology, we examine the prospects of combining these two probes to constrain cosmological and HOD parameters. We find that the combination indeed results in noticeable better constraints, in particular because the cross-covariance introduces a synergy between the probes on small scales....

  15. Dyschromia related to severe combined immunodeficiency.

    Science.gov (United States)

    Maldonado-Cid, Paola; Noguera-Morel, Lucero; Moreno-Alonso-de-Celada, Ricardo; De-Lucas-Laguna, Raúl; Feito-Rodríguez, Marta; Beato-Merino, Maria José; Casado-Jiménez, Mariano

    2013-12-01

    Severe combined immunodeficiency includes a group of diseases characterized by different inherited immunological defects. A 4-month-old girl diagnosed with Omenn syndrome, a subtype of severe combined immunodeficiency presenting with generalized erythroderma, was referred to our hospital for an allogeneic stem cell transplantation. Days before transplantation, she developed hyperpigmented macules that increased in number in the following months. As the erythroderma resolved after transplantation, diffuse hypopigmentation was simultaneously noted together with the expansion of hyperpigmented lesions. Cutaneous biopsy samples were taken at different moments, showing features of Omenn syndrome at first, and 2 months later changes consistent with hypopigmentation and repigmentation were observed. Although pigmentary disorders are rarely described in this context, these must be taken into account as a possible alternative diagnosis to graft-versus-host disease and toxicoderma in immunosuppressed patients.

  16. Object attributes combine additively in visual search.

    Science.gov (United States)

    Pramod, R T; Arun, S P

    2016-01-01

    We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes.

  17. Non-target impact of fungicide tetraconazole on microbial communities in soils with different agricultural management.

    Science.gov (United States)

    Sułowicz, Sławomir; Cycoń, Mariusz; Piotrowska-Seget, Zofia

    2016-08-01

    Effect of the fungicide tetraconazole on microbial community in silt loam soils from orchard with long history of triazole application and from grassland with no known history of fungicide usage was investigated. Triazole tetraconazole that had never been used on these soils before was applied at the field rate and at tenfold the FR. Response of microbial communities to tetraconazole was investigated during 28-day laboratory experiment by determination of changes in their biomass and structure (phospholipid fatty acids method-PLFA), activity (fluorescein diacetate hydrolysis-FDA) as well as changes in genetic (DGGE) and functional (Biolog) diversity. Obtained results indicated that the response of soil microorganisms to tetraconazole depended on the management of the soils. DGGE patterns revealed that both dosages of fungicide affected the structure of bacterial community and the impact on genetic diversity and richness was more prominent in orchard soil. Values of stress indices-the saturated/monounsaturated PLFAs ratio and the cyclo/monounsaturated precursors ratio, were almost twice as high and the Gram-negative/Gram-positive ratio was significantly lower in the orchard soil compared with the grassland soil. Results of principal component analysis of PLFA and Biolog profiles revealed significant impact of tetraconazole in orchard soil on day 28, whereas changes in these profiles obtained for grassland soil were insignificant or transient. Obtained results indicated that orchards soil seems to be more vulnerable to tetraconazole application compared to grassland soil. History of pesticide application and agricultural management should be taken into account in assessing of environmental impact of studied pesticides.

  18. Importance of inoculum properties on the structure and growth of bacterial communities during Recolonisation of humus soil with different pH.

    Science.gov (United States)

    Pettersson, Marie; Bååth, Erland

    2013-08-01

    The relationship between community structure and growth and pH tolerance of a soil bacterial community was studied after liming in a reciprocal inoculum study. An unlimed (UL) humus soil with a pH of 4.0 was fumigated with chloroform for 4 h, after which soil was experimentally limed (EL) to a pH of 7.6. Both the UL and the EL soil were then reciprocally inoculated with UL soil or field limed (FL) soil with a pH of 6.2. The FL soil was from a 15-year-old experiment. The structural changes were measured on both bacteria in soil and on bacteria able to grow on agar plates using phospholipids fatty acid (PLFA) and denaturing gradient gel electrophoresis (DGGE) analysis. The developing community pH tolerance and bacterial growth were also monitored over time using thymidine incorporation. The inoculum source had a significant impact on both growth and pH tolerance of the bacterial community in the EL soil. These differences between the EL soil inoculated with UL soil and FL soil were correlated to structural changes, as evidenced by both PLFA and DGGE analyses on the soil. Similar correlations were seen to the fraction of the community growing on agar plates. There were, however, no differences between the soil bacterial communities in the unlimed soils with different inocula. This study showed the connection between the development of function (growth), community properties (pH tolerance) and the structure of the bacterial community. It also highlighted the importance of both the initial properties of the community and the selection pressure after environmental changes in shaping the resulting microbial community.

  19. Characterization of humus microbial communities in adjacent forest types that differ in nitrogen availability.

    Science.gov (United States)

    Leckie, S E; Prescott, C E; Grayston, S J; Neufeld, J D; Mohn, W W

    2004-07-01

    To address the link between soil microbial community composition and soil processes, we investigated the microbial communities in forest floors of two forest types that differ substantially in nitrogen availability. Cedar-hemlock (CH) and hemlock-amabilis fir (HA) forests are both common on northern Vancouver Island, B.C., occurring adjacently across the landscape. CH forest floors have low nitrogen availability and HA high nitrogen availability. Total microbial biomass was assessed using chloroform fumigation-extraction and community composition was assessed using several cultivation-independent approaches: denaturing gradient gel electrophoresis (DGGE) of the bacterial communities, ribosomal intergenic spacer analysis (RISA) of the bacterial and fungal communities, and phospholipid fatty acid (PLFA) profiles of the whole microbial community. We did not detect differences in the bacterial communities of each forest type using DGGE and RISA, but differences in the fungal communities were detected using RISA. PLFA analysis detected subtle differences in overall composition of the microbial community between the forest types, as well as in particular groups of organisms. Fungal PLFAs were more abundant in the nitrogen-poor CH forests. Bacteria were proportionally more abundant in HA forests than CH in the lower humus layer, and Gram-positive bacteria were proportionally more abundant in HA forests irrespective of layer. Bacterial and fungal communities were distinct in the F, upper humus, and lower humus layers of the forest floor and total biomass decreased in deeper layers. These results indicate that there are distinct patterns in forest floor microbial community composition at the landscape scale, which may be important for understanding nutrient availability to forest vegetation.

  20. Dextromethorphan and Quinidine Combination for Heroin Detoxification

    OpenAIRE

    2008-01-01

    Dextromethorphan (DM) is a low-affinity, non-competitive NMDA receptor antagonist that has shown promise in pre-clinical and preliminary clinical studies for the reduction of opioid withdrawal symptoms, but when used at higher doses, it is associated with deleterious side effects attributed to its metabolite, dextrorphan. A clinical trial was therefore conducted to test the withdrawal-suppressant effect of a combination of dextromethorphan with quinidine (DM/Q). Quinidine inhibits the metabol...

  1. Inpainting with sparse linear combinations of exemplars

    Energy Technology Data Exchange (ETDEWEB)

    Wohlberg, Brendt [Los Alamos National Laboratory

    2008-01-01

    We introduce a new exemplar-based inpainting algorithm based on representing the region to be inpainted as a sparse linear combination of blocks extracted from similar parts of the image being inpainted. This method is conceptually simple, being computed by functional minimization, and avoids the complexity of correctly ordering the filling in of missing regions of other exemplar-based methods. Initial performance comparisons on small inpainting regions indicate that this method provides similar or better performance than other recent methods.

  2. Combined production of broilers and fruits

    OpenAIRE

    Lindhard Pedersen, H.; Olsen, A.; Pedersen, B; Korsgaard, M.; Horsted, K

    2004-01-01

    Combined production of broilers and fruit trees is a subject often discussed in organic fruit production in Denmark. Very little research has been carried out on this type of production system. In organic production in Denmark, nearly no pesticides are allowed, so the need for alternative pest control is large. Apple sawfly (Hoplocampa testudinea) and pear midge (Contarinia pyrivora) cause big crop losses in apples and pears respectively, in unsprayed organic fruit production. ...

  3. Chapter 23: Combined Heat and Power

    Energy Technology Data Exchange (ETDEWEB)

    Simons, George [Itron, Davis, CA (United States); Barsun, Stephan [Itron, Davis, CA (United States)

    2016-11-01

    This protocol defines a combined heat and power (CHP) measure as a system that sequentially generates both electrical energy and useful thermal energy from one fuel source at a host customer's facility or residence. This protocol is aimed primarily at regulators and administrators of ratepayer-funded CHP programs; however, project developers may find the protocol useful to understand how CHP projects are evaluated.

  4. Screening for severe combined immunodeficiency in neonates

    OpenAIRE

    Kelly BT; Tam JS; Verbsky JW; Routes JM

    2013-01-01

    Brian T Kelly,1 Jonathan S Tam,1 James W Verbsky,1,2 John M Routes1,2 1Department of Pediatrics, 2Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI, USA Abstract: Severe combined immunodeficiency (SCID) is a rare disease that severely affects the cellular and humoral immune systems. Patients with SCID present with recurrent or severe infections and often with chronic diarrhea and failure to thrive. The disease is uniformly fatal, making early diag...

  5. Center for Hypersonic Combined Cycle Flow Physics

    Science.gov (United States)

    2015-03-24

    team of expert experimentalists and numerical and chemical kinetic modelers. Flowfields were examined in the turbine /ramjet dual inlet mode transition...at the University of Virginia for extensive data acquisition using various techniques, including OH PLIF, CARS , TDLAS, TDLAT and SPIV. It was...SUBJECT TERMS Hypersonic combined cycle propulsion, turbine /ram dual-inlet transition, ram/scram dual-mode transition, hypervelocity regime, RANS, Hybrid

  6. Combination prediction method of chaotic time series

    Institute of Scientific and Technical Information of China (English)

    ZHAO DongHua; RUAN Jiong; CAI ZhiJie

    2007-01-01

    In the present paper, we propose an approach of combination prediction of chaotic time series. The method is based on the adding-weight one-rank local-region method of chaotic time series. The method allows us to define an interval containing a future value with a given probability, which is obtained by studying the prediction error distribution. Its effectiveness is shown with data generated by Logistic map.

  7. Combination Therapy for Diabetic Macular Edema

    Directory of Open Access Journals (Sweden)

    Dinah Zur

    2012-01-01

    Full Text Available Diabetic macular edema is a main reason for visual loss in diabetic patients. Until recent years, macular laser photocoagulation was the only available therapy. The awareness that inflammation is an important factor in the pathogenetic process of DME gave reason for intravitreal treatment with corticosteroids. The introduction of anti-VEGF drugs brought a revolutionary change in the treatment of DME. This paper will review the important clinical trials with an emphasis on combination therapies.

  8. [Combination therapy of chronic bacterial prostatitis].

    Science.gov (United States)

    Khryanin, A A; Reshetnikov, O V

    2016-08-01

    The article discusses the possible etiological factors in the development of chronic bacterial prostatitis. The authors presented a comparative long-term analysis of morbidity from non-viral sexually transmitted infections (STIs) in Russia. Against the background of general decline in STIs incidence, a significant percentage of them is made up by urogenital trichomoniasis. The findings substantiated the advantages of combination therapy (ornidazole and ofloxacin) for bacterial urinary tract infections.

  9. Surgical and Prosthetic Rehabilitation of Combination Syndrome

    Directory of Open Access Journals (Sweden)

    Paolo Carlino

    2014-01-01

    Full Text Available The aim of this report is to analyze the clinical symptoms, ethologic factors, and prosthetic rehabilitation in a case of Combination Syndrome (CS. The treatment of CS can be conventional or surgical, with or without the bone reconstruction of maxilla. The correct prosthetic treatment helps this kind of patients to restore the physiologic occlusion plane to allow a correct masticatory and aesthetic function. Management of this kind of patients can be a challenge for a dental practitioner.

  10. FOXN1 deficient nude severe combined immunodeficiency

    OpenAIRE

    Rota, Ioanna A.; Dhalla, Fatima

    2017-01-01

    Nude severe combined immunodeficiency is a rare inherited disease caused by autosomal recessive loss-of-function mutations in FOXN1. This gene encodes a transcription factor essential for the development of the thymus, the primary lymphoid organ that supports T-cell development and selection. To date nine cases have been reported presenting with the clinical triad of absent thymus resulting in severe T-cell immunodeficiency, congenital alopecia universalis and nail dystrophy. Diagnosis relies...

  11. Early diagnosis of severe combined immunodeficiency syndrome.

    OpenAIRE

    Hague, R A; Rassam, S; Morgan, G; Cant, A. J.

    1994-01-01

    Infants with severe combined immunodeficiency syndrome (SCIDS) have a greatly improved prognosis if diagnosed and treated before they develop overwhelming infection. Clinical and laboratory data on 45 patients with SCIDS were retrospectively reviewed to assess the value of absolute lymphocyte counts in making an early diagnosis. Ninety infants matched for age, sex, and presenting symptoms were used as controls. Thirteen (29%) infants with SCIDS were diagnosed at birth as previous siblings had...

  12. Prenatal exclusion of severe combined immunodeficiency

    OpenAIRE

    Levinsky, R J; Linch, D. C.; Beverly, C L; Rodeck, C.

    1982-01-01

    By analysing leucocyte subpopulations with monoclonal antisera, we have shown that the diagnosis of severe combined immunodeficiency can be made soon after birth. The technique of staining has been adapted for small blood samples, and normal ranges of leucocyte subpopulations have been established for fetal blood taken from mid-trimester pregnancies. Using this information, we gave prenatal advice to an at risk family and predicted that the pregnancy would be normal; this was confirmed after ...

  13. A new combination in Erica (Ericaceae

    Directory of Open Access Journals (Sweden)

    Boratynski, A.

    2010-12-01

    Full Text Available A new nomenclatural status and combination is proposed for Erica cinerea var. numidica. New data about the morphology, chorology and ecology of this taxon are given.Se propone un nuevo estatus y combinación nomenclatural para Erica cinerea var. numidica. Se aportan nuevos datos sobre la morfología, corología y ecología de este taxón.

  14. Combined photovacuum therapy of copulative dysfunction

    Science.gov (United States)

    Menyaev, Yulian A.; Zharov, Vladimir P.; Mishanin, Evgeniy A.; Kuzmich, Aleksandr P.; Bessonov, Sergey E.

    2006-02-01

    One of the important problems of modern medicine is treatment of urogenital diseases. 1-2 There is a set of the treatment methods for such problems, but any of them does not obey the modern physicians completely. 3-4 Our aim is to present the new combined therapeutic apparatus called "Yarovit" (produced in Russia, in collaboration between Bauman Moscow State University of Technology and Scientific Production Association and Medical Center "Yarovit") which successfully applied in clinics for cure the patients with copulative dysfunction diseases. 5-6 At this apparatus "Yarovit" (description model have abbreviation AMVL-0 1) there is a combination of vacuum decompression (0.1-0.4 kgs/cm2) and light emitting diodes matrix system (660 nm, 1-3 mW/cm2). In treatment procedure apparatus can be applied together with expanded module "Intratherm" (39 °C on average), which has rectal heating elements. The latest clinical studies were made together with volunteer participation of more then one hundred patients, and received results showed the good dynamic of healing. That let to conclude these combinations of physical therapeutic methods supplement each other and in conjunction provides a significant clinical effect. The further developments of such apparatuses are discussed.

  15. Regulatory requirements for marketing fixed dose combinations

    Directory of Open Access Journals (Sweden)

    B G Jayasheel

    2010-01-01

    Full Text Available The development of fixed-dose combinations (FDCs is becoming increasingly important from a public health perspective. FDCs have advantages when there is an identifiable patient population for whom treatment with a particular combination of actives in a fixed ratio is safe and effective and when all of the actives contribute to the overall therapeutic effect. Such combinations of drugs are particularly useful in the management of chronic diseases. In addition, there can be real clinical benefits in the form of increased efficacy and/or a reduced incidence of adverse effects. Additional advantages of FDCs are potentially lower costs of manufacturing compared to the costs of producing separate products administered concurrently, simpler logistics of distribution and reduced development of resistance in the case of antimicrobials. Above all, FDC therapy reduces pill burden and improves medication compliance. Although, FDCs seem to be ideal under certain pre-defined circumstances, if a dosing adjustment is warranted, there may not be an FDC available in the most appropriate strength for the patient and if an adverse drug reaction occurs from using an FDC, it may be difficult to identify the active ingredient responsible for causing the reaction. Appendix VI of Schedule Y (Drugs & Cosmetics Rules 1945, India states the requirements for marketing approval of various types of FDCs. The same is further elaborated in this article to provide a detailed guidance including the clinical trial requirements. However, the heterogeneity of the therapeutic field makes it difficult to develop a standard guidance document.

  16. The 2004 ATLAS Combined Test Beam

    CERN Multimedia

    The ATLAS CTB Team, .

    2004-01-01

    In the year 2004, ATLAS has been involved in a huge combined test beam (CTB) effort in H8. A complete slice of the barrel detector and of the Muon End-cap has been tested, with the following clear goals: pre-commission the final elements and study the detector performance in a realistic combined data taking. Thanks to this experience, a lot of expertise in the operations has been acquired and much data (~ 4.6 TB of data, ~ 90 million events on castor) has been collected and is already under analysis. The CTB has been characterized by different phases with an incremental presence of sub-detectors modules and associated DAQ infrastructure, as well as incremental improvement of analysis tools for prompt data certification. The physics goals of the CTB have been defined in consultation with the physics coordinator, all the sub-detector representatives and the combined performance group representative. With all these indications, a detailed run plan day-by-day schedule was defined before the CTB start and was foll...

  17. Maps of combined geohazards for regional planning

    Science.gov (United States)

    Hanisch, J.

    2003-04-01

    Geohazard maps have turned out to be an extremely useful tool for urban and regional planning purposes. The planners have the opportunity to recognize at first glance where, e.g., frequent landsliding has to be expected. These maps usually cover only one type of natural or geological risks, such as, landslides, earthquakes or thunder-storms. As most of the natural hazards are connected with other threatening natural events (earthquakes with landslides, volcanic eruptions with lahars, thunder-storms with floods, landslides and debris flows) a new semi-quantitative approach is made to show all kinds of geohazards and their combinations in one map. For each kind of hazard a ranking has to be elaborated resulting in hazard zones. The overlay of these individual hazard zone maps (e.g. earthquake zones and areas with landslide susceptibility zones) results in combined hazard maps. The combination with zones of (human) vulnerability provides the final risk zones for the politicians and planners. The use of GIS is a matter of course.

  18. Correcting and combining time series forecasters.

    Science.gov (United States)

    Firmino, Paulo Renato A; de Mattos Neto, Paulo S G; Ferreira, Tiago A E

    2014-02-01

    Combined forecasters have been in the vanguard of stochastic time series modeling. In this way it has been usual to suppose that each single model generates a residual or prediction error like a white noise. However, mostly because of disturbances not captured by each model, it is yet possible that such supposition is violated. The present paper introduces a two-step method for correcting and combining forecasting models. Firstly, the stochastic process underlying the bias of each predictive model is built according to a recursive ARIMA algorithm in order to achieve a white noise behavior. At each iteration of the algorithm the best ARIMA adjustment is determined according to a given information criterion (e.g. Akaike). Then, in the light of the corrected predictions, it is considered a maximum likelihood combined estimator. Applications involving single ARIMA and artificial neural networks models for Dow Jones Industrial Average Index, S&P500 Index, Google Stock Value, and Nasdaq Index series illustrate the usefulness of the proposed framework.

  19. Combined effects of radiation and trauma

    Science.gov (United States)

    Messerschmidt, Otfried

    Injuries, caused by both whole-body irradiation and wounds or burns, have been relatively little studied. Possibly because many investigators think that these injuries are just modified radiation-induced diseases for which the same treatment principles are valid. Other authors had the impression that, for instance, the radiation burn trauma is a new kind of disease which differs significantly from either radiation syndrome alone or from burn disease. There are many experimental data on animals which suggest that the pathology of combined injuries differs significantly from that of radiation-induced disease or of thermal or mechanical traumas. Wounds or burns which, in general, do not cause septicaemia could become entrance ports for bacteria when animals are exposed to whole-body irradiation. Thrombocytopenia is the reason for hemorrhages in wounds. The susceptibility to shock is increased considerably in combined injuries and the formation of callus in the bone fractures is significantly delayed. The healing of wounds and burns in the initial phase of the radiation syndrome does not always differ from healing in the non-irradiated organism. However, a few days or weeks later very serious wound infections and hemorrhages can occur. The additional injuries almost always worsen the development and prognosis of radiation-induced disease. The recommended treatment for combined injuries will differ in many respects from the treatment of wounds and burns or the radiation syndrome.

  20. Combining classifiers for robust PICO element detection

    Directory of Open Access Journals (Sweden)

    Grad Roland

    2010-05-01

    Full Text Available Abstract Background Formulating a clinical information need in terms of the four atomic parts which are Population/Problem, Intervention, Comparison and Outcome (known as PICO elements facilitates searching for a precise answer within a large medical citation database. However, using PICO defined items in the information retrieval process requires a search engine to be able to detect and index PICO elements in the collection in order for the system to retrieve relevant documents. Methods In this study, we tested multiple supervised classification algorithms and their combinations for detecting PICO elements within medical abstracts. Using the structural descriptors that are embedded in some medical abstracts, we have automatically gathered large training/testing data sets for each PICO element. Results Combining multiple classifiers using a weighted linear combination of their prediction scores achieves promising results with an f-measure score of 86.3% for P, 67% for I and 56.6% for O. Conclusions Our experiments on the identification of PICO elements showed that the task is very challenging. Nevertheless, the performance achieved by our identification method is competitive with previously published results and shows that this task can be achieved with a high accuracy for the P element but lower ones for I and O elements.

  1. Gasification combined cycle power generation - process alternatives

    Energy Technology Data Exchange (ETDEWEB)

    Kurkela, E.; Korhonen, M.

    1988-01-01

    Interest in Integrated Gasification Combined Cycle (IGCC) power plants has recently increased also in Finland. The IGCC systems offer the potential of superior efficiency and environmental performance over conventional pulverized coal or peat fired boilers. Potential applications are both large-scale electricity production from coal and medium-scale combined heat and electricity production. In the latter case, the gasification process should also be applicable to peat and wood. Several IGCC processes have been developed in USA and in Europe. These processes differ from each other in many respects. Nearest to commercialization are processes, which employ oxygen gasification and cold gas cleanup. The Cool Water plant, which was brought into operation in 1984 in USA, has demonstrated the feasibility of an IGCC system using Texaco entrained-bed gasifier. Several pressurized fluidized-bed and fixed-bed gasification processes have also reached a pilot or demonstration stage with a wide variety of coals from lignite to hard coal. Pressurized fluidized-bed gasification of peat (Rheinbraun-HTW-process) will also be demonstrated at the peat ammonia plant of Kemira Oy, which will be commissioned in 1988 in Oulu, Finland. Oxygen gasification and cold gas cleanup are, however, economically viable only in large-scale applications. Technology is being developed to simplify the IGCC system, in order to reduce its capital costs and increase its efficiency. Air gasification combined with ho gas cleanup seems to have a great potential of improving the competitiveness of the IGCC system.

  2. Combined PET/CT in oncology

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Keon Wook [National Cancer Center, Goyang (Korea, Republic of)

    2002-02-01

    Presently, PET is widely used in oncology, but suffers from limitations of poor anatomical information. To compensate for this weakness, a combined PET/CT has been developed by Professor Townsend at the University of Pittsburgh Medical Center. The prototype was designed as PET and CT components combined serially in a gantry. The CT images provide not only accurate anatomical location of the lesions but also transmission map for attenuation correction. More than 300 cancer patients have been studied with the prototype of PET/CT since July, 1998. The PET/TC studies affected the managements in about 20{approx}30% of cancer patients. These changes are a consequence of the more accurate localization of functional abnormalities, and the distinction of pathological from normal physiological uptake. Now a variety of combined PET/CT scanners with high-end PET and high-end CT components are commercially available. With the high speed of multi-slice helical CT, throughput of patient's increases compared to conventional PET. Although some problems (such as a discrepancy in breathing state between the two modalities) still remain, the role of PET/CT in oncology is very promising.

  3. Unsupervised Retinal Vessel Segmentation Using Combined Filters.

    Directory of Open Access Journals (Sweden)

    Wendeson S Oliveira

    Full Text Available Image segmentation of retinal blood vessels is a process that can help to predict and diagnose cardiovascular related diseases, such as hypertension and diabetes, which are known to affect the retinal blood vessels' appearance. This work proposes an unsupervised method for the segmentation of retinal vessels images using a combined matched filter, Frangi's filter and Gabor Wavelet filter to enhance the images. The combination of these three filters in order to improve the segmentation is the main motivation of this work. We investigate two approaches to perform the filter combination: weighted mean and median ranking. Segmentation methods are tested after the vessel enhancement. Enhanced images with median ranking are segmented using a simple threshold criterion. Two segmentation procedures are applied when considering enhanced retinal images using the weighted mean approach. The first method is based on deformable models and the second uses fuzzy C-means for the image segmentation. The procedure is evaluated using two public image databases, Drive and Stare. The experimental results demonstrate that the proposed methods perform well for vessel segmentation in comparison with state-of-the-art methods.

  4. Unsupervised Retinal Vessel Segmentation Using Combined Filters.

    Science.gov (United States)

    Oliveira, Wendeson S; Teixeira, Joyce Vitor; Ren, Tsang Ing; Cavalcanti, George D C; Sijbers, Jan

    2016-01-01

    Image segmentation of retinal blood vessels is a process that can help to predict and diagnose cardiovascular related diseases, such as hypertension and diabetes, which are known to affect the retinal blood vessels' appearance. This work proposes an unsupervised method for the segmentation of retinal vessels images using a combined matched filter, Frangi's filter and Gabor Wavelet filter to enhance the images. The combination of these three filters in order to improve the segmentation is the main motivation of this work. We investigate two approaches to perform the filter combination: weighted mean and median ranking. Segmentation methods are tested after the vessel enhancement. Enhanced images with median ranking are segmented using a simple threshold criterion. Two segmentation procedures are applied when considering enhanced retinal images using the weighted mean approach. The first method is based on deformable models and the second uses fuzzy C-means for the image segmentation. The procedure is evaluated using two public image databases, Drive and Stare. The experimental results demonstrate that the proposed methods perform well for vessel segmentation in comparison with state-of-the-art methods.

  5. A review of combinations of electrokinetic applications.

    Science.gov (United States)

    Moghadam, Mohamad Jamali; Moayedi, Hossein; Sadeghi, Masoud Mirmohamad; Hajiannia, Alborz

    2016-12-01

    Anthropogenic activities contaminate many lands and underground waters with dangerous materials. Although polluted soils occupy small parts of the land, the risk they pose to plants, animals, humans, and groundwater is too high. Remediation technologies have been used for many years in order to mitigate pollution or remove pollutants from soils. However, there are some deficiencies in the remediation in complex site conditions such as low permeability and complex composition of some clays or heterogeneous subsurface conditions. Electrokinetic is an effective method in which electrodes are embedded in polluted soil, usually vertically but in some cases horizontally, and a low direct current voltage gradient is applied between the electrodes. The electric gradient initiates movement of contaminants by electromigration (charged chemical movement), electro-osmosis (movement of fluid), electrolysis (chemical reactions due to the electric field), and diffusion. However, sites that are contaminated with heavy metals or mixed contaminants (e.g. a combination of organic compounds with heavy metals and/or radionuclides) are difficult to remediate. There is no technology that can achieve the best results, but combining electrokinetic with other remediation methods, such as bioremediation and geosynthetics, promises to be the most effective method so far. This review focuses on the factors that affect electrokinetic remediation and the state-of-the-art methods that can be combined with electrokinetic.

  6. Genetic compatibility determines endophyte-grass combinations.

    Directory of Open Access Journals (Sweden)

    Kari Saikkonen

    Full Text Available Even highly mutually beneficial microbial-plant interactions, such as mycorrhizal- and rhizobial-plant exchanges, involve selfishness, cheating and power-struggles between the partners, which depending on prevailing selective pressures, lead to a continuum of interactions from antagonistic to mutualistic. Using manipulated grass-endophyte combinations in a five year common garden experiment, we show that grass genotypes and genetic mismatches constrain genetic combinations between the vertically (via host seeds transmitted endophytes and the out-crossing host, thereby reducing infections in established grass populations. Infections were lost in both grass tillers and seedlings in F(1 and F(2 generations, respectively. Experimental plants were collected as seeds from two different environments, i.e., meadows and nearby riverbanks. Endophyte-related benefits to the host included an increased number of inflorescences, but only in meadow plants and not until the last growing season of the experiment. Our results illustrate the importance of genetic host specificity and trans-generational maternal effects on the genetic structure of a host population, which act as destabilizing forces in endophyte-grass symbioses. We propose that (1 genetic mismatches may act as a buffering mechanism against highly competitive endophyte-grass genotype combinations threatening the biodiversity of grassland communities and (2 these mismatches should be acknowledged, particularly in breeding programmes aimed at harnessing systemic and heritable endophytes to improve the agriculturally valuable characteristics of cultivars.

  7. On Coding Non-Contiguous Letter Combinations

    Directory of Open Access Journals (Sweden)

    Frédéric eDandurand

    2011-06-01

    Full Text Available Starting from the hypothesis that printed word identification initially involves the parallel mapping of visual features onto location-specific letter identities, we analyze the type of information that would be involved in optimally mapping this location-specific orthographic code onto a location-invariant lexical code. We assume that some intermediate level of coding exists between individual letters and whole words, and that this involves the representation of letter combinations. We then investigate the nature of this intermediate level of coding given the constraints of optimality. This intermediate level of coding is expected to compress data while retaining as much information as possible about word identity. Information conveyed by letters is a function of how much they constrain word identity and how visible they are. Optimization of this coding is a combination of minimizing resources (using the most compact representations and maximizing information. We show that in a large proportion of cases, non-contiguous letter sequences contain more information than contiguous sequences, while at the same time requiring less precise coding. Moreover, we found that the best predictor of human performance in orthographic priming experiments was within-word ranking of conditional probabilities, rather than average conditional probabilities. We conclude that from an optimality perspective, readers learn to select certain contiguous and non-contiguous letter combinations as information that provides the best cue to word identity.

  8. Reports from the Combined Performance Working Groups

    CERN Multimedia

    S. Haywood

    The main goal of the Combined Performance Groups is to study the detector performance for physics, as well as to monitor the effect of changes to the detector layout and the evolution of the software. The groups combine the expertise available in several different subdetectors. In addition, they are responsible for developing combined reconstruction algorithms and are involved in the calibration of energy scales and optimising resolutions. For the Workshop, the four groups made a real effort to compare the reconstruction in Athena (the "New" C++ software framework) and Atrecon (the "Old" software used for the TDR studies). b-tagging Working Group: Over the last few months, the description of the Inner Detector in the simulation has become more realistic, following the evolution of the detector design. This has caused the amount of material in the simulation to increase and the Pixel B-layer has been moved to a larger radius to allow for a wider beam-pipe. Nevertheless, the good performance of the b-tagging (...

  9. PCR-DGGE method to assess the diversity of BTEX mono-oxygenase genes at contaminated sites

    NARCIS (Netherlands)

    Hendrickx, B; Dejonghe, W; Faber, F; Boenne, W; Bastiaens, L; Verstraete, W; Top, EM; Springael, D

    2006-01-01

    tmoA and related genes encode the alpha-subunit of the hydroxylase component of the major group (subgroup 1 of subfamily 2) of bacterial multicomponent mono-oxygenase enzyme complexes involved in aerobic benzene, toluene, ethylbenzene and xylene (BTEX) degradation. A PCR-denaturing gradient gel elec

  10. Artisanal and experimental Pecorino Siciliano cheese: Microbial dynamics during manufacture assessed by culturing and PCR-DGGE analyses

    NARCIS (Netherlands)

    Randazzo, C.L.; Vaughan, E.E.; Caggia, C.

    2006-01-01

    Traditional artisanal Pecorino Siciliano (PS) cheeses, and two experimental PS cheeses were manufactured using either raw or pasteurised ewes' milk with the addition of starter cultures. The bacterial diversity and dynamics of the different cheese types were evaluated both by culturing and character

  11. ARISA and DGGE as fingerprinting techniques for assessing bacterial community structure in the rumen of small ruminants

    OpenAIRE

    Saro, C.; Molina Alcaide, E.; Ranilla, María José; Abecia, L.; Carro Travieso, Mª Dolores

    2014-01-01

    Trabajo presentado al Proceedings of the 30th Biennial Conference of the Australian Society of Animal Production 2014. Harnessing the Ecology and Physiology of Herbivores (Camberra, Australia, 8 al 12 septiembre, 2014).

  12. DGGE based whole-gene mutation scanning of the dystrophlin gene in Duchenne and Becker muscular dystrophy patients

    NARCIS (Netherlands)

    Hofstra, RMW; Mulder, IM; Vossen, R; de Koning-Gans, PAM; Kraak, M; Ginjaar, IB; van der Hout, AH; Bakker, E; Buys, CHCM; van Essen, AJ; den Dunnen, JT

    2004-01-01

    Duchenne and Becker muscular dystrophy (DMD and BMD) are caused by mutations in the dystrophin gene. Large rearrangements in the gene are found in about two,thirds of DMD patients, with similar to60% carrying deletions and 5-10% carrying duplications. Most of the remaining 30-35% of patients are exp

  13. Assessment of nematode biodiversity using DGGE of 18S rDNA following extraction of nematodes from soil

    NARCIS (Netherlands)

    Foucher, A.L.J.L.; Bongers, A.M.T.; Noble, L.R.; Wilson, M.J.

    2004-01-01

    Soil nematodes are both taxonomically and functionally diverse, respond quickly to soil perturbation and have much potential as indicators of soil health. However, because of the perceived difficulty of identifying nematodes to species level morphologically, they are frequently neglected in soil eco

  14. Microbial degradation of 4-monobrominated diphenyl ether in an aerobic sludge and the DGGE analysis of diversity.

    Science.gov (United States)

    Chen, Chun-Yao; Wang, Chun-Kang; Shih, Yang-Hsin

    2010-07-01

    Polybrominated diphenyl ethers (PBDEs) were applied as flame retardant additives in polymers for many plastic and electronic products. Due to their ubiquitous distribution in the environment, potential toxicity to human and tendency for bioaccumulation, PBDEs have raised public safety concern. In this study we examined the degradation of 4-monobrominated diphenyl ether (4-BDE) in aerobic sludge, as a model for PBDE biodegradation. Degradation of 4-BDE was observed in aerobic sludge. Co-metabolism with toluene or diphenyl ether facilitated 4-BDE biodegradation in terms of kinetics and efficiency. Diphenyl ether seems to perform slightly better as an auxiliary carbon source than toluene in facilitating 4-BDE degradation. During the experiment we identified diphenyl ether by gas chromatography/mass spectrometry(GC/MS), which indicates that an anaerobic debromination has occurred. Bacterial community composition was monitored with denaturing gradient gel electrophoresis. The fragments enriched in 4-BDE-degrading aerobic sludge samples belong to presumably a novel anaerobic Clostridiales species distantly related to all known debrominating microbes. This suggests that 4-BDE biodegradation can occur in anaerobic micro-niche in an apparently aerobic environment, by a previously unknown bacterial species. These findings can provide better understandings of biodegradation of brominated diphenyl ethers and can facilitate the prediction of the fate of PBDEs in the environment.

  15. Bacterial community analysis in chlorpyrifos enrichment cultures via DGGE and use of bacterial consortium for CP biodegradation.

    Science.gov (United States)

    Akbar, Shamsa; Sultan, Sikander; Kertesz, Michael

    2014-10-01

    The organophosphate pesticide chlorpyrifos (CP) has been used extensively since the 1960s for insect control. However, its toxic effects on mammals and persistence in environment necessitate its removal from contaminated sites, biodegradation studies of CP-degrading microbes are therefore of immense importance. Samples from a Pakistani agricultural soil with an extensive history of CP application were used to prepare enrichment cultures using CP as sole carbon source for bacterial community analysis and isolation of CP metabolizing bacteria. Bacterial community analysis (denaturing gradient gel electrophoresis) revealed that the dominant genera enriched under these conditions were Pseudomonas, Acinetobacter and Stenotrophomonas, along with lower numbers of Sphingomonas, Agrobacterium and Burkholderia. Furthermore, it revealed that members of Bacteroidetes, Firmicutes, α- and γ-Proteobacteria and Actinobacteria were present at initial steps of enrichment whereas β-Proteobacteria appeared in later steps and only Proteobacteria were selected by enrichment culturing. However, when CP-degrading strains were isolated from this enrichment culture, the most active organisms were strains of Acinetobacter calcoaceticus, Pseudomonas mendocina and Pseudomonas aeruginosa. These strains degraded 6-7.4 mg L(-1) day(-1) of CP when cultivated in mineral medium, while the consortium of all four strains degraded 9.2 mg L(-1) day(-1) of CP (100 mg L(-1)). Addition of glucose as an additional C source increased the degradation capacity by 8-14 %. After inoculation of contaminated soil with CP (200 mg kg(-1)) disappearance rates were 3.83-4.30 mg kg(-1) day(-1) for individual strains and 4.76 mg kg(-1) day(-1) for the consortium. These results indicate that these organisms are involved in the degradation of CP in soil and represent valuable candidates for in situ bioremediation of contaminated soils and waters.

  16. DGGE analysis of buffalo manure eubacteria for hydrogen production: effect of pH, temperature and pretreatments.

    Science.gov (United States)

    Carillo, Petronia; Carotenuto, Claudia; Di Cristofaro, Filomena; Kafantaris, Ioannis; Lubritto, Carmine; Minale, Mario; Morrone, Biagio; Papa, Stefania; Woodrow, Pasqualina

    2012-12-01

    Buffalo dung is a low-cost substrate with plenty of carbohydrates, an optimal carbon/nitrogen ratio, and a rich microbial flora, and could become a valuable source of biogas. Therefore, in the present study we compared the type and amount of specific eubacteria to the different configurations of pH, temperature and thermal pretreatment after fermentation in batch reactors in order to understand the suitability of buffalo manure for hydrogen production. The phylogenetic structure of the microbial community in fermentation samples was studied using denaturing gradient gel electrophoresis to generate fingerprints of 16S rRNA genes. The sequences analysis revealed abundance of the phyla Bacteroidetes and Firmicutes, and in particular of the order Clostridiales. Very active hydrogen producing bacteria belonging to Clostridium cellulosi species were identified demonstrating the suitability of this substrate to produce hydrogen. Moreover, a large fraction of 16S-rDNA amplicons could not be assigned to lower taxonomic ranks, demonstrating that numerous microorganisms involved in anaerobic fermentation in digesters or bioreactors are still unclassified or unknown.

  17. Combined Hormonal Birth Control: Pill, Patch, and Ring

    Science.gov (United States)

    ... AQ FREQUENTLY ASKED QUESTIONS FAQ185 CONTRACEPTION Combined Hormonal Birth Control: Pill, Patch, and Ring • What are combined hormonal birth control methods? • How do combined hormonal methods prevent pregnancy? • ...

  18. [Diagnosis of pancreatic injuries in closed combined trauma].

    Science.gov (United States)

    Panasenko, S I; Baramiia, N M; Dorosh, V M

    2003-08-01

    Problems of diagnosis of the closed pancreatic injury (CPI) in combined trauma are discussed. The CPI peculiarity in closed combined trauma is the absence of pathognomonic symptoms. Rational application of instrumental diagnostic methods permits to diagnose CPI in combined trauma.

  19. Fixed Dose Combination for TB treatment

    Directory of Open Access Journals (Sweden)

    Tjandra Y. Aditama

    2003-06-01

    Full Text Available According to the World Health Organization, a third of the world’s population is infected with tuberculosis. The disease is responsible for nearly 2 million deaths each year and over 8 million were developing active diseases. Moreover, according to WHO (2000, tuberculosis deaths are estimated to increase to 35 million between 2000-2020. The majority of tuberculosis patients worldwide are still treated with single drugs, or with 2-drug fixed-dose combinations (FDCs. To improve tuberculosis treatment, 2- and 3-drug FDCs were recommended by the World Health Organization (WHO as part of the DOTS strategy. Since 1999 a 4-drug FDC was included on the WHO Model List of Essential Drugs. Today, FDCs are important tools to further improve the quality of care for people with TB, and accelerate DOTS expansion to reach the global TB control targets. Fixed dose combination TB drugs could simplifies both treatment and management of drug supply, and may prevent the emergence of drug resistance .Prevention of drug resistance is just one of the potential benefits of the use of FDCs. FDCs simplify administration of drugs by reducing the number of pills a patient takes each day and decreasing the risk of incorrect prescriptions. Most tuberculosis patients need only take 3–4 FDCs tablets per day during the intensive phase of treatment, instead of the 15–16 tablets per day that is common with single-drug formulations It is much simpler to explain to patients that they need to take four tablets of the same type and colour, rather than a mixture of tablets of different shapes, colours and sizes. Also, the chance of taking an incomplete combination of drugs is eliminated, since the four essential drugs are combined into one tablet. FDCs are also simpler for care-givers as they minimize the risk of confusion. Finally, drug procurement, in all its components (stock management, shipping, distribution, is simplified by FDCs. Adverse reactions to drugs are not more

  20. Combining disparate data for decision making

    Science.gov (United States)

    Gettings, M. E.

    2010-12-01

    Combining information of disparate types from multiple data or model sources is a fundamental task in decision making theory. Procedures for combining and utilizing quantitative data with uncertainties are well-developed in several approaches, but methods for including qualitative and semi-quantitative data are much less so. Possibility theory offers an approach to treating all three data types in an objective and repeatable way. In decision making, biases are frequently present in several forms, including those arising from data quality, data spatial and temporal distribution, and the analyst's knowledge and beliefs as to which data or models are most important. The latter bias is particularly evident in the case of qualitative data and there are numerous examples of analysts feeling that a qualitative dataset is more relevant than a quantified one. Possibility theory and fuzzy logic now provide fairly general rules for quantifying qualitative and semi-quantitative data in ways that are repeatable and minimally biased. Once a set of quantified data and/or model layers is obtained, there are several methods of combining them to obtain insight useful in decision making. These include: various combinations of layers using formal fuzzy logic (for example, layer A and (layer B or layer C) but not layer D); connecting the layers with varying influence links in a Fuzzy Cognitive Map; and using the set of layers for the universe of discourse for agent based model simulations. One example of logical combinations that have proven useful is the definition of possible habitat for valley fever fungus (Coccidioides sp.) using variables such as soil type, altitude, aspect, moisture and temperature. A second example is the delineation of the lithology and possible mineralization of several areas beneath basin fill in southern Arizona. A Fuzzy Cognitive Map example is the impacts of development and operation of a hypothetical mine in an area adjacent to a city. In this model