These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Whole-genome analysis of porcine epidemic diarrhea virus (PEDV) from eastern China.  

PubMed

The complete genome sequence of a porcine epidemic diarrhea virus variant, strain SHQP/YM/2013, from China was determined and compared with those of other porcine epidemic diarrhea viruses. The full-length genome was 28,038 nucleotides (nt) in length without the poly (A) tail, and it was similar to that of other reported PEDV strains, with the characteristic gene order 5'-replicase (1a/1b) -S-ORF3-E-M-N-3'. Nucleotide sequence analysis based on individual virus genes indicated a close relationship between the S gene of SHQP/YM/2013 and those of the four Korean field strains from 2008-2009. Its ORF3 gene, however, fell into three groups. Recent prevalent Chinese PEDV field isolates were divided between group 1 and group 3, which suggests that the recent prevalent Chinese PEDV field isolates represent a new genotype that differs from the genotype that includes the vaccine strains. Based on phylogenetic analysis of the M gene, ORF3 gene and S gene, our study demonstrated that prevalent PEDV isolates in China may have originated from Korean strains. This report describes the complete genome sequence of SHQP/YM/2013, and the data will promote a better understanding of the molecular epidemiology and genetic diversity of PEDV field isolates in eastern China. PMID:24818713

Yang, De-Quan; Ge, Fei-Fei; Ju, Hou-Bin; Wang, Jian; Liu, Jian; Ning, Kun; Liu, Pei-Hong; Zhou, Jin-Ping; Sun, Quan-Yun

2014-10-01

2

Cell culture isolation and sequence analysis of genetically diverse US porcine epidemic diarrhea virus strains including a novel strain with a large deletion in the spike gene.  

PubMed

The highly contagious and deadly porcine epidemic diarrhea virus (PEDV) first appeared in the US in April 2013. Since then the virus has spread rapidly nationwide and to Canada and Mexico causing high mortality among nursing piglets and significant economic losses. Currently there are no efficacious preventive measures or therapeutic tools to control PEDV in the US. The isolation of PEDV in cell culture is the first step toward the development of an attenuated vaccine, to study the biology of PEDV and to develop in vitro PEDV immunoassays, inactivation assays and screen for PEDV antivirals. In this study, nine of 88 US PEDV strains were isolated successfully on Vero cells with supplemental trypsin and subjected to genomic sequence analysis. They differed genetically mainly in the N-terminal S protein region as follows: (1) strains (n=7) similar to the highly virulent US PEDV strains; (2) one similar to the reportedly US S INDEL PEDV strain; and (3) one novel strain most closely related to highly virulent US PEDV strains, but with a large (197aa) deletion in the S protein. Representative strains of these three genetic groups were passaged serially and grew to titers of ?5-6log10 plaque forming units/mL. To our knowledge, this is the first report of the isolation in cell culture of an S INDEL PEDV strain and a PEDV strain with a large (197aa) deletion in the S protein. We also designed primer sets to detect these genetically diverse US PEDV strains. PMID:25217400

Oka, Tomoichiro; Saif, Linda J; Marthaler, Douglas; Esseili, Malak A; Meulia, Tea; Lin, Chun-Ming; Vlasova, Anastasia N; Jung, Kwonil; Zhang, Yan; Wang, Qiuhong

2014-10-10

3

Distinct Characteristics and Complex Evolution of PEDV Strains, North America, May 2013-February 2014  

PubMed Central

Porcine epidemic diarrhea virus (PEDV), which emerged in the United States in 2013, has spread throughout North America. Limited availability of PEDV complete genomes worldwide has impeded our understanding of PEDV introduction into the United States. To determine the relationship between the North American strains and global emerging and historic PEDV strains, we sequenced and analyzed complete genomes of 74 strains from North America; the strains clustered into 2 distinct clades. Compared with the initially reported virulent US PEDV strains, 7 (9.7%) strains from 4 states contained insertions and deletions in the spike gene (S INDELs). These S INDEL strains share 99.8%–100% nt identity with each other and 96.2%–96.7% nt identity with the initial US strains. Furthermore, the S INDEL strains form a distinct cluster within North American clade II, sharing 98.6%–100% nt identity overall. In the United States, the S INDEL and original PEDV strains are co-circulating and could have been introduced simultaneously. PMID:25279722

Vlasova, Anastasia N.; Wang, Qiuhong; Culhane, Marie R.; Rossow, Kurt D.; Rovira, Albert; Collins, James; Saif, Linda J.

2014-01-01

4

Transverse Magnetic Field Propellant Isolator  

NASA Technical Reports Server (NTRS)

An alternative high voltage isolator for electric propulsion and ground-based ion source applications has been designed and tested. This design employs a transverse magnetic field that increases the breakdown voltage. The design can greatly enhance the operating range of laboratory isolators used for high voltage applications.

Foster, John E.

2000-01-01

5

Isolation and characterization of porcine epidemic diarrhea viruses associated with the 2013 disease outbreak among swine in the United States.  

PubMed

Porcine epidemic diarrhea virus (PEDV) was detected in May 2013 for the first time in U.S. swine and has since caused significant economic loss. Obtaining a U.S. PEDV isolate that can grow efficiently in cell culture is critical for investigating pathogenesis and developing diagnostic assays and for vaccine development. An additional objective was to determine which gene(s) of PEDV is most suitable for studying the genetic relatedness of the virus. Here we describe two PEDV isolates (ISU13-19338E and ISU13-22038) successfully obtained from the small intestines of piglets from sow farms in Indiana and Iowa, respectively. The two isolates have been serially propagated in cell culture for over 30 passages and were characterized for the first 10 passages. Virus production in cell culture was confirmed by PEDV-specific real-time reverse-transcription PCR (RT-PCR), immunofluorescence assays, and electron microscopy. The infectious titers of the viruses during the first 10 passages ranged from 6 × 10(2) to 2 × 10(5) 50% tissue culture infective doses (TCID50)/ml. In addition, the full-length genome sequences of six viruses (ISU13-19338E homogenate, P3, and P9; ISU13-22038 homogenate, P3, and P9) were determined. Genetically, the two PEDV isolates were relatively stable during the first 10 passages in cell culture. Sequences were also compared to those of 4 additional U.S. PEDV strains and 23 non-U.S. strains. All U.S. PEDV strains were genetically closely related to each other (?99.7% nucleotide identity) and were most genetically similar to Chinese strains reported in 2011 to 2012. Phylogenetic analyses using different genes of PEDV suggested that the full-length spike gene or the S1 portion is appropriate for sequencing to study the genetic relatedness of these viruses. PMID:24197882

Chen, Qi; Li, Ganwu; Stasko, Judith; Thomas, Joseph T; Stensland, Wendy R; Pillatzki, Angela E; Gauger, Phillip C; Schwartz, Kent J; Madson, Darin; Yoon, Kyoung-Jin; Stevenson, Gregory W; Burrough, Eric R; Harmon, Karen M; Main, Rodger G; Zhang, Jianqiang

2014-01-01

6

Gradient isolator for flow field of fuel cell assembly  

DOEpatents

Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions.

Ernst, William D. (Troy, NY)

1999-01-01

7

Gradient isolator for flow field of fuel cell assembly  

DOEpatents

Isolator(s) include isolating material and optionally gasketing material strategically positioned within a fuel cell assembly. The isolating material is disposed between a solid electrolyte and a metal flow field plate. Reactant fluid carried by flow field plate channel(s) forms a generally transverse electrochemical gradient. The isolator(s) serve to isolate electrochemically a portion of the flow field plate, for example, transversely outward from the channel(s), from the electrochemical gradient. Further, the isolator(s) serve to protect a portion of the solid electrolyte from metallic ions. 4 figs.

Ernst, W.D.

1999-06-15

8

Expression and Purification of the scFv from hybridoma cells secreting a monoclonal antibody against S PROTEIN of PEDV.  

PubMed

The variable regions of the heavy chain (VH) and light chain (VL) were amplified by RT-PCR from the hybridoma 6E6, which secretes the monoclonal antibody against PEDV S protein. The VL and VH amplicons were combined using SOE-PCR by a 12 amino acid flexible linker (SSGGGGSGGGGS), which produced the scFv gene (named scFv/6E6). After sequence analysis, the scFv/6E6 gene was cloned into the prokaryotic expression vector pGEX-6p-1 with a GST-tag. The recombinant scFv/6E6 protein was successfully expressed in recombinant Escherichia coli by IPTG induction. Moreover, the recombinant scFv/6E6 protein was purified from the inclusion body form by the gel-cutting measure followed by electroelution and dialysis. The recombinant scFv/6E6 protein reported here will provide some basis for further antiviral drug research based on the scFv molecule. PMID:23600505

Zhu, Qinghe; Guo, Donghua; Feng, Li; Sun, Dongbo

2013-02-01

9

Expression and Purification of the scFv from Hybridoma Cells Secreting a Monoclonal Antibody Against S Protein of PEDV  

PubMed Central

The variable regions of the heavy chain (VH) and light chain (VL) were amplified by RT-PCR from the hybridoma 6E6, which secretes the monoclonal antibody against PEDV S protein. The VL and VH amplicons were combined using SOE-PCR by a 12 amino acid flexible linker (SSGGGGSGGGGS), which produced the scFv gene (named scFv/6E6). After sequence analysis, the scFv/6E6 gene was cloned into the prokaryotic expression vector pGEX-6p-1 with a GST-tag. The recombinant scFv/6E6 protein was successfully expressed in recombinant Escherichia coli by IPTG induction. Moreover, the recombinant scFv/6E6 protein was purified from the inclusion body form by the gel-cutting measure followed by electroelution and dialysis. The recombinant scFv/6E6 protein reported here will provide some basis for further antiviral drug research based on the scFv molecule. PMID:23600505

Zhu, Qinghe; Guo, Donghua; Feng, Li

2013-01-01

10

In Vitro Susceptibilities of Mycoplasma hyopneumoniae Field Isolates  

PubMed Central

The in vitro susceptibilities of 21 Mycoplasma hyopneumoniae field isolates were determined using a broth microdilution technique. One isolate showed acquired resistance to lincomycin, tilmicosin, and tylosin, while five isolates were resistant to flumequine and enrofloxacin. Acquired resistance against these antimicrobials in M. hyopneumoniae field isolates was not reported previously. PMID:15504886

Vicca, J.; Stakenborg, T.; Maes, D.; Butaye, P.; Peeters, J.; de Kruif, A.; Haesebrouck, F.

2004-01-01

11

Isolated Attosecond Pulses using a Detuned Second-harmonic Field  

SciTech Connect

Calculations are presented for the generation of an isolated attosecond pulse in a multicycle two-color strong-field regime. We show that the recollision of the electron wave packet can be confined to half an optical cycle using pulses of up to 40 fs in duration. The scheme is proven to be efficient using two intense beams, one producing a strong field at {omega} and the other a strong field detuned from 2{omega}. The slight detuning {delta}{omega} of the second harmonic is used to break the symmetry of the electric field over many optical cycles and provides a coherent control for the formation of an isolated attosecond pulse.

Merdji, Hamed; /Saclay /SLAC, PULSE; Auguste, Thierry; Boutu, Willem; Caumes, J.-Pascal; Carre, Bertrand; /Saclay; Pfeifer, Thomas; Jullien, Aurelie; Neumark, Daniel M.; Leone, Stephen R.; /UC, Berkeley /LBL, Berkeley

2007-11-07

12

Concentration- and time-response characteristics of plaque isolates of Agrotis ipsilon multiple nucleopolyhedrovirus derived from a field isolate.  

PubMed

Plaque isolates derived from the Illinois field isolate of Agrotis ipsilon multiple nucleopolyhedrovirus are distinguished by the presence or absence of a small deletion in the baculovirus egt (ecdysteroid UDP-glucosyltransferase) coding sequence. In concentration-response and time-response bioassays with both plaque and field isolates, plaque isolates with a mutated egt gene were less pathogenic against A. ipsilon larvae than other isolates, but killed larvae faster. Mixed infections with isolates representing the two different egt genotypes caused the same level of mortality as the field isolate and a plaque isolate with a wild-type egt gene. PMID:23220242

Harrison, Robert L

2013-02-01

13

Immunogenicity and protective efficacy of recombinant S1 domain of the porcine epidemic diarrhea virus spike protein.  

PubMed

Porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric pathogen of swine. Acute PEDV outbreaks have continually emerged in most swine-producing Asian countries and, recently, in the United States, causing significant economic losses in the pig industry. The spike (S) protein of PEDV is a type 1 transmembrane envelope glycoprotein and consists of the S1 and S2 domains, which are responsible for virus binding and fusion, respectively. Since the S1 domain is involved in a specific high-affinity interaction with the cellular receptor and induction of neutralizing antibody in the natural host, it is a primary target for the development of effective vaccines against PEDV. In this study, a codon-optimized PEDV S1 gene containing amino acid residues 25-738 was synthesized based on a multiple alignment of the S amino acid sequences of PEDV field isolates and used to establish a stable porcine cell line constitutively expressing the PEDV S1 protein. The purified recombinant S1 protein was found to mediate highly potent antibody responses in immunized rabbits. The antibodies strongly recognized the recombinant S1 protein from cell lysates and supernatants of S1-expressing cells, whereas they bound weakly to the authentic S protein of PEDV vaccine strain SM98-1. Furthermore, a serum neutralization test revealed that the rabbit antisera completely inhibit infection of the PEDV vaccine strain at a serum dilution of 1:16. We then tested the ability of vaccination with the recombinant S1 protein to protect piglets against PEDV. Late-term pregnant sows were inoculated intramuscularly with the purified S1 protein, and the outcome was investigated in passively immunized suckling piglets after a virulent PEDV challenge. The results showed that vaccination with S1 protein efficiently protected neonatal piglets against PEDV. Our data suggest that the recombinant S1 protein shows potential as an effective and safe subunit vaccine for PED prevention. PMID:25008896

Oh, Jongsuk; Lee, Kyung-Won; Choi, Hwan-Won; Lee, Changhee

2014-11-01

14

Genetic diversity of Mycosphaerella graminicola isolates from a single field.  

PubMed

Septoria tritici blotch caused by Mycosphaerella graminicola is currently one of the most economically damaging diseases on wheat crops worldwide. Two hundred and sixty single-conidial isolates of this fungus were sampled in April 2012 in the Nord-Pas de Calais region (France). They have all been collected from 13 distinct plots in a single field. The corresponding isolates were then fingerprinted using 8 microsatellite markers in order to assess the genetic diversity and population structure of M. graminicola at the single field scale. The results revealed a high genotypic diversity within the collected population, with the detection of 83% of unique haplotypes among the isolates tested (clonal fraction = 17%). A high genic diversity was also found as indicated by the Nei's index value (0.50) and strong allele diversity obtained (number of alleles per locus ranged from 7 to 17, with an average of 10 alleles per locus). Further analyses showed a low population differentiation (G(ST) = 0.08) and a high gene flow (Nm = 5.64) between the 13 sampled plots. Our study suggests that sexual reproduction, by its frequency, plays a major role in the genetic diversification of M. graminicola at the field level and in the distribution and homogenization of this diversity in the field via wind-born ascospores. PMID:25151819

Siah, A; Reignault, Ph; Halama, P

2013-01-01

15

Change in antimicrobial susceptibility of Mycoplasma gallisepticum field isolates.  

PubMed

This study compares the antimicrobial susceptibility over time between two groups of Mycoplasma gallisepticum (MG) isolates from the same geographical area. Minimum inhibitory concentration of 13 antimicrobials was determined against two groups of MG isolates from chickens. Group 1 strains (n=22) were isolated in 2004-2005 while group 2 strains (n=7) were isolated in 2007-2008. Minimum inhibitory concentration 50 for group 1 versus group 2 was 4/4, 0.5/0.5, ? 0.031/? 64, ? 0.031/2, ? 0.031/0.125, 1/0.5, 1/1, ? 0.031/? 0.031, ? 0.031/2, ? 0.031/2, 1/4, ? 0.031/0.062, and 0.062/2 ?g/ml against gentamicin, spectinomycin, erythromycin, tilmicosin, tylosin, florfenicol, thiamphenicol, tiamulin, ciprofloxacin, enrofloxacin, chlortetracycline, doxycycline, and oxytetracycline, respectively. There was a statistically significant increase in resistance of group 2 to erythromycin, tilmicosin, tylosin, ciprofloxacin, enrofloxacin, chlortetracycline, doxycycline, and oxytetracycline. This dramatic increase in resistance against 8 antimicrobials belonging to three different families of antimicrobials in a relatively short period of time appears to be rare and of concern. The cause of this increased resistance observed in group 2 of MG isolates was not determined and should be further investigated. Monitoring of MG field strain susceptibility is highly recommended to implement successful treatment and prophylaxis programs in endemic areas. PMID:21382675

Gharaibeh, Saad; Al-Rashdan, Mohammad

2011-06-01

16

Formation, evolution and properties of isolated field elliptical galaxies  

NASA Astrophysics Data System (ADS)

We study the properties, evolution and formation mechanisms of isolated field elliptical (IfE) galaxies. We create a `mock' catalogue of IfE galaxies from the Millennium Simulation Galaxy Catalogue, and trace their merging histories. The formation, identity and assembly redshifts of simulated isolated and non-isolated elliptical galaxies are studied and compared. Observational and numerical data are used to compare age, mass and the colour-magnitude relation. Our results, based on simulation data, show that almost 7 per cent of all elliptical galaxies brighter than -19mag in B band can be classified as IfE galaxies. Results also show that isolated elliptical galaxies have a rather flat luminosity function; a number density of ~3 × 10-6h3Mpc-3mag-1, throughout their B-band magnitudes. IfE galaxies show bluer colours than non-isolated elliptical galaxies and they appear younger, in a statistical sense, according to their mass-weighted age. IfE galaxies also form and assemble at lower redshifts compared to non-isolated elliptical galaxies. About 46 per cent of IfE galaxies have undergone at least one major merging event in their formation history, while the same fraction is only ~33 per cent for non-isolated ellipticals. Almost all (~98 per cent) isolated elliptical galaxies show merging activity during their evolution, pointing towards the importance of mergers in the formation of IfE galaxies. The mean time of the last major merging is at z ~ 0.6 or 6Gyr ago for isolated ellipticals, while non-isolated ellipticals experience their last major merging significantly earlier at z ~ 1.1 or 8Gyr ago. After inspecting merger trees of simulated IfE galaxies, we conclude that three different, yet typical, formation mechanisms can be identified: solitude, coupling and cannibalism. Our results also predict a previously unobserved population of blue, dim and light galaxies that fulfil observational criteria to be classified as IfE galaxies. This separate population comprises ~26 per cent of all IfEs.

Niemi, Sami-Matias; Heinämäki, Pekka; Nurmi, Pasi; Saar, Enn

2010-06-01

17

Extensive population synthesis of isolated neutron stars with field decay  

E-print Network

We perform population synthesis studies of different types of neutron stars taking into account the magnetic field decay. For the first time, we confront our results with observations using {\\it simultaneously} the Log N -- Log S distribution for nearby isolated neutron stars, the Log N -- Log L distribution for magnetars, and the distribution of radio pulsars in the $P$ -- $\\dot P$ diagram. We find that our theoretical model is consistent with all sets of data if the initial magnetic field distribution function follows a log-normal law with $ \\sim 13.25$ and $\\sigma_{\\log B_0}\\sim 0.6$. The typical scenario includes about 10% of neutron stars born as magnetars, significant magnetic field decay during the first million years of a NS life. Evolutionary links between different subclasses may exist, although robust conclusions are not yet possible. We apply the obtained field distribution and the model of decay to study long-term evolution of neuton stars till the stage of accretion from the interstellar medium....

Popov, S B; Miralles, J A; Pons, J A; Posselt, B

2010-01-01

18

Field isolations of Dirofilaria from mosquitoes in Alabama.  

PubMed

Field collections of mosquitoes were made April-September 1977 and 1978 in the immediate vicinity of a hunting-dog kennel where the dogs had a chronic history of heartworm infection. Among 19 mosquito species taken in light-trap collections, only Aedes sticticus, Ae. vexans, and Anopheles punctipennis were found infected with what were presumed to be D. immitis larvae. Based on natural infection rates and the relative abundance of these three host species, An. punctipennis and Ae. sticticus appear to be among the most important vectors of dog heartworm at this site. Despite its greater abundance, Ae. vexans apparently plays a comparatively lesser role in D. immitis transmission owing to low natural infection rates and the development of only a few filariae per host. All Dirofilaria isolations were made in April, May, and June, suggesting that transmission may occur primarily during the spring and early summer in this area. PMID:7365629

Buxton, B A; Mullen, G R

1980-02-01

19

Bacillus huizhouensis sp. nov., isolated from a paddy field soil.  

PubMed

A Gram-stain positive, facultative aerobic bacterium, designated as strain GSS03(T), was isolated from a paddy field soil. The cells were observed to be endospore forming, rod-shaped and motile with flagella. The organism was found to grow optimally at 35 °C at pH 7.0 and in the presence of 1 % NaCl. The strain was classified as a novel taxon within the genus Bacillus on the basis of phenotypic and phylogenetic analyses. The closest phylogenetic relatives were identified as Bacillus psychrosaccharolyticus DSM 6(T) (97.61 %), Bacillus muralis DSM 16288(T) (97.55 %), Bacillus asahii JCM 12112(T) (97.48 %), Bacillus simplex DSM 1321(T) (97.48 %) and "Bacillus frigoritolerans" DSM 8801(T) (97.38 %). The menaquinone was identified as MK-7, the major cellular fatty acid was identified as anteiso-C15:0 and the major cellular polar lipids as phosphatidylethanolamine, phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and three unknown polar lipids. The DNA G+C content was determined to be 40.2 mol%. The DNA-DNA relatedness with the closest relatives was below 48 %. Therefore, on the basis of all the results, strain GSS03(T) is considered to represent a novel species within the genus Bacillus, for which the name Bacillus huizhouensis sp. nov. is proposed. The type strain is GSS03(T) (=KCTC 33172(T) =CCTCC AB 2013237(T)). PMID:24903955

Li, Jibing; Yang, Guiqin; Wu, Min; Zhao, Yong; Zhou, Shungui

2014-08-01

20

Studies of resistance to anticoccidials in Eimeria field isolates and pure Eimeria strains.  

PubMed

Ten Eimeria field isolates from North Germany were studied in battery tests for sensitivity to selected anticoccidials. A high percentage of the Eimeria field isolates (9 out of 10) showed resistance to anticoccidials, mostly multiple resistance. Partial or complete resistance to maduramicin was found in 7 field isolates, to monensin in 6, to salinomycin in 5, to nicarbazin in 8, to halofuginone in 7, to robenidine and toltrazuril in 1, and to diclazuril in 2 field isolates. Multiple resistance had developed in 7 of the 10 isolates. Cross-resistance between maduramicin, monensin, and salinomycin occurred in 5 Eimeria isolates. One isolate showed cross-resistance between diclazuril and toltrazuril. From the resistant isolates 15 pure E. acerculina and 5 pure E. brunetti strains were obtained by single oocyst infections. Seven of the E. acerculina and 4 of the E. brunetti strains showed resistance or partial resistance that was also present in the original isolate. Ten of 11 resistant strains were multiply resistant. PMID:9187026

Stephen, B; Rommel, M; Daugschies, A; Haberkorn, A

1997-04-01

21

Genetic analysis of mycobacterium avium subspecies paratuberculosis reveals sequence and epigenetic variation among field isolates  

E-print Network

GENTIC ANLYSI OF Mycobacterium avium subspecis partuberculosi REVALS EQUENCE AND EPIGENTIC VARITION AMONG FIELD ISOLATES A Dissertation by BRIAN JAMES O?SHEA Submited to the Ofice of Graduate Studies of Txas A&M University in partil... fulfilment of the rquirmnts for the dgre of DOCTR OF PHILOSPHY Decmber 207 Major Subject: Vetrinary Microbilogy GENTIC ANLYSI OF Mycobacterium avium subspecis partuberculosi REVALS EQUENCE AND EPIGENTIC VARITION AMONG FIELD ISOLATES...

O'Shea, Brian James

2009-05-15

22

Evaluation of bradyrhizobia strains isolated from field-grown soybean plants in Argentina as improved inoculants  

Microsoft Academic Search

Bradyrhizobium strains were isolated from nodules obtained from field-grown soybean plants sampled in 12 soybean production locations in Argentina. These fields had been annually cropped with soybean and did not show decreases in yields even though they had been neither N-fertilized nor inoculated for at least the last 5 years. We hypothesized that the isolated strains maintained high competitiveness and efficiency

Mariana Melchiorre; Marcos J. de Luca; Gustavo Gonzalez Anta; Paola Suarez; Ramiro Lascano; Roberto W. Racca

2011-01-01

23

Comparative Analysis of the Genomes of Two Field Isolates of the Rice Blast Fungus Magnaporthe oryzae  

PubMed Central

Rice blast caused by Magnaporthe oryzae is one of the most destructive diseases of rice worldwide. The fungal pathogen is notorious for its ability to overcome host resistance. To better understand its genetic variation in nature, we sequenced the genomes of two field isolates, Y34 and P131. In comparison with the previously sequenced laboratory strain 70-15, both field isolates had a similar genome size but slightly more genes. Sequences from the field isolates were used to improve genome assembly and gene prediction of 70-15. Although the overall genome structure is similar, a number of gene families that are likely involved in plant-fungal interactions are expanded in the field isolates. Genome-wide analysis on asynonymous to synonymous nucleotide substitution rates revealed that many infection-related genes underwent diversifying selection. The field isolates also have hundreds of isolate-specific genes and a number of isolate-specific gene duplication events. Functional characterization of randomly selected isolate-specific genes revealed that they play diverse roles, some of which affect virulence. Furthermore, each genome contains thousands of loci of transposon-like elements, but less than 30% of them are conserved among different isolates, suggesting active transposition events in M. oryzae. A total of approximately 200 genes were disrupted in these three strains by transposable elements. Interestingly, transposon-like elements tend to be associated with isolate-specific or duplicated sequences. Overall, our results indicate that gain or loss of unique genes, DNA duplication, gene family expansion, and frequent translocation of transposon-like elements are important factors in genome variation of the rice blast fungus. PMID:22876203

Li, Zhigang; Hu, Songnian; Yao, Nan; Dean, Ralph A.; Zhao, Wensheng; Shen, Mi; Zhang, Haiwang; Li, Chao; Liu, Liyuan; Cao, Lei; Xu, Xiaowen; Xing, Yunfei; Hsiang, Tom; Zhang, Ziding; Xu, Jin-Rong; Peng, You-Liang

2012-01-01

24

Isolation and Expulsion of Divergences in Quantum Field Theory  

E-print Network

Divergences that arise in the quantization of scalar quantum field models by means of a lattice-space functional integration may be attributed to a single integration variable, and this fact is demonstrated by showing that if the integrand for that single integration variable is appropriately changed, then a perturbation expansion becomes order-by-order finite and divergence free. The paper concludes with a brief review of a current proposal of how an auxiliary, nonclassical potential added to the lattice action of a relativistic scalar field quantization may automatically render an analogous change of the integrand, and thus may lead, as well, to nontrivial and divergence-free results.

John R. Klauder

1995-10-11

25

Field experiment on transpiration from isolated urban plants  

Microsoft Academic Search

The effect of pot plant density on plant transpiration rate was examined in a series of field experiments. Three spatial densities were created using 203 nearly homogeneous pot plants; the ratios of plant separation to plant height were 0Ð25, 0Ð5, and 3 for the 'high,' 'medium,' and 'low' groups respectively. The daily transpiration rate of 55 pot plants was measured

Aya Hagishima; Ken-Ich Narita; Jun Tanimoto

2007-01-01

26

Isolation of Gravity Effects on Diffusion Flames by Magnetic Field  

Microsoft Academic Search

We present the experimental demonstration of the ability of magnetic field to remove buoyancy effects on flames. The experiment\\u000a consists to observing the shape and colour changes of a laminar jet diffusion flame located in the air-gap of a Bitter magnet\\u000a able to delivering up 650 T2\\/m in magnetic gradient intensity. At some critical (predicted theoretically) value of the upward magnetic

Fouad Khaldi; Karim Messadek; Adel Mustapha Benselama

2010-01-01

27

Full field imaging of isolated metallic nano objects  

NASA Astrophysics Data System (ADS)

Since the detection of nanoparticles is a major issue in nano sciences, we have developed two instruments for the fast imaging of individual nano objects. The first one is based on a spatial modulation of the sample using an incoherent dark field illumination and a multiplexed lock in detection. The second instrument uses digital heterodyne holography. Both instruments make it possible to achieve a high signal-to-noise ratio and therefore to detect very low signal.

Absil, E.; Tessier, G.; Fournier, D.; Gross, M.; Atlan, M.

2009-07-01

28

Molecular Characterization of Acquired Enrofloxacin Resistance in Mycoplasma synoviae Field Isolates  

PubMed Central

The in vitro activity of enrofloxacin against 73 Mycoplasma synoviae field strains isolated in Israel and Europe was determined by broth microdilution. Decreased susceptibility to enrofloxacin was identified in 59% of strains, with the MICs ranging from 1 to >16 ?g/ml. The estimated MIC50 and MIC90 values for enrofloxacin were 2 and 8 ?g/ml, respectively. Moreover, this study showed that 92% of recent Israeli field isolates (2009 to 2011) of M. synoviae have MICs of ?2 ?g/ml to enrofloxacin. Comparison of the quinolone resistance-determining regions (QRDRs) in M. synoviae isolates revealed a clear correlation between the presence of one of the amino acid substitutions Asp79-Asn, Thr80-Ala/Ile, Ser81-Pro, and Asp84-Asn/Tyr/His of the ParC QRDR and decreased susceptibility to enrofloxacin (MIC, ?1 ?g/ml). Amino acid substitutions at positions GyrA 87, GyrB 401/402, and ParE 420/454 were also identified, but there was no clear-cut correlation with susceptibility to enrofloxacin. Comparison of vlhA molecular profiles revealed the presence of 9 different genotypes in the Israeli M. synoviae field isolates and 10 genotypes in the European isolates; only one vlhA genotype (type 4) was identified in both cohorts. Based on results of vlhA molecular typing, several mechanisms for emergence and dissemination of Israeli enrofloxacin-resistant M. synoviae isolates are suggested. PMID:23612192

Gerchman, I.; Mikula, I.; Gobbo, F.; Catania, S.; Levisohn, S.

2013-01-01

29

Differentiation of field isolates and vaccine strains of infectious laryngotracheitis virus by DNA sequencing.  

PubMed

Two different regions of the infected cell protein 4 (ICP4) gene of infectious laryngotracheitis virus (ILTV) were amplified and sequenced for characterization of field isolates and tissue culture-origin (TCO) and chicken embryo-origin (CEO) vaccine strains. Phylogenetic analysis of the two regions showed differences in nucleotide and amino acid sequences between field isolates and attenuated vaccines. The PCR-RFLP results were identical to those obtained by DNA sequencing and validated their use to differentiate ILTV strains. The approach using the sequencing of the two fragments of the ICP4 gene showed to be an efficient and practical procedure to differentiate between field isolates and vaccine strains of ILTV. PMID:19747995

Chacón, Jorge Luis; Ferreira, Antonio J Piantino

2009-11-12

30

Quantitative Field Testing Heterodera glycines from Metagenomic DNA Samples Isolated Directly from Soil under Agronomic Production  

PubMed Central

A quantitative PCR procedure targeting the Heterodera glycines ortholog of the Caenorhabditis elegans uncoordinated-78 gene was developed. The procedure estimated the quantity of H. glycines from metagenomic DNA samples isolated directly from field soil under agronomic production. The estimation of H. glycines quantity was determined in soil samples having other soil dwelling plant parasitic nematodes including Hoplolaimus, predatory nematodes including Mononchus, free-living nematodes and biomass. The methodology provides a framework for molecular diagnostics of nematodes from metagenomic DNA isolated directly from field soil. PMID:24587100

Li, Yan; Lawrence, Gary W.; Lu, Shien; Balbalian, Clarissa; Klink, Vincent P.

2014-01-01

31

Detection and Isolation Techniques for Methanogens from Microbial Mats (in the El Tatio Geyser Field, Chile)  

Microsoft Academic Search

Isolating methanogenic archea from an extreme environment such as El Tatio (high altitude, arid climate) gives insight to the methanogenic taxas able to adapt and grow under extreme conditions. The hydrothermal waters at El Tatio geyser field demonstrate extreme geochemical conditions, with discharge water from springs and geysers at local boiling temperature (85° C) with high levels of arsenic and

E. Z. Pearson; M. A. Franks; P. Bennett

2010-01-01

32

Responses of broiler chickens orally challenged with Clostridium perfringens isolated from field cases of necrotic enteritis  

Microsoft Academic Search

The present study examines the responses of broiler chickens to oral administration of Clostridium perfringens freshly isolated from field cases of necrotic enteritis (NE). The challenge studies included long-term exposure and short-term exposure, factored in with dietary and management variables including high levels of dietary components such as fish meal, meat meal, abrupt change of feed, and fasting. In the

A. A. Olkowski; C. Wojnarowicz; M. Chirino-Trejo; M. D. Drew

2006-01-01

33

Evaluating the Resistance of Eimeria Spp. Field Isolates to Anticoccidial Drugs Using Three Different Indices  

PubMed Central

Background In this study, the presence of resistance to diclazuril, amprolium+ethopabate and salinomycin, representing some of the commonest anticoccidials in Iran's poultry industry, against three mixed Eimeria field isolates were investigated. Methods Three Eimeria field isolates, collected from typical broiler farms in Iran, were propagated once, inoculated to 480 broilers, comprising 30 chicks in each treatment. The non-medicated or medicated diets containing one of the above mentioned anticoccidials were provided ad-lib. Drug efficacy was determined using the Global index (GI), Anticoccidial Sensitivity Test (AST) and Optimum Anticoccidial Activity (OAA). Results None of the field isolates were fully sensitive to the selected anticoccidials. All isolates showed reduced sensitivity/partial resistance to salinomycin. Resistance to amprolium+ethopabate was evident and partial to complete resistance was recorded for diclazuril. Conclusion Limited efficacy of the selected anticoccidials is obvious. Considering the cost of continuous use of anticoccidials in the field, altering the prevention strategy and rotation of the anticoccidials with better efficacy, would prevent further economic losses induced by coccidiosis. PMID:23914236

Arabkhazaeli, F; Modrisanei, M; Nabian, S; Mansoori, B; Madani, A

2013-01-01

34

RubberBand: Augmenting Teacher's Awareness of Spatially Isolated Children on Kindergarten Field Trips  

E-print Network

benefits to the children, stimulating self-motivation, creativity, and long-lasting memories [10-specific educational goals, and making proper interventions for children in need. Even the temporary disappearanceRubberBand: Augmenting Teacher's Awareness of Spatially Isolated Children on Kindergarten Field

35

Optimum design of bridges with superelastic-friction base isolators against near-field earthquakes  

NASA Astrophysics Data System (ADS)

The seismic response of a multi-span continuous bridge isolated with novel superelastic-friction base isolator (S-FBI) is investigated under near-field earthquakes. The isolation system consists of a flat steel-Teflon sliding bearing and a superelastic NiTi shape memory alloy (SMA) device. Sliding bearings limit the maximum seismic forces transmitted to the superstructure to a certain value that is a function of friction coefficient of sliding interface. Superelastic SMA device provides restoring capability to the isolation system together with additional damping characteristics. The key design parameters of an S-FBI system are the natural period of the isolated, yielding displacement of SMA device, and the friction coefficient of the sliding bearings. The goal of this study is to obtain optimal values for each design parameter by performing sensitivity analyses of the isolated bridge. First, a three-span continuous bridge is modeled as a two-degrees-of-freedom with S-FBI system. A neuro-fuzzy model is used to capture rate-dependent nonlinear behavior of SMA device. A time-dependent method which employs wavelets to adjust accelerograms to match a target response spectrum with minimum changes on the other characteristics of ground motions is used to generate ground motions used in the simulations. Then, a set of nonlinear time history analyses of the isolated bridge is performed. The variation of the peak response quantities of the isolated bridge is shown as a function of design parameters. Also, the influence of temperature variations on the effectiveness of S-FBI system is evaluated. The results show that the optimum design of the isolated bridge with S-FBI system can be achieved by a judicious specification of design parameters.

Ozbulut, Osman E.; Hurlebaus, Stefan

2010-04-01

36

In vitro activity of pyronaridine against field isolates and reference clones of Plasmodium falciparum.  

PubMed

Pyronaridine, a 9-substituted 1-aza-acridine, was assayed for in vitro activity against clinical and field isolates as well as characterized clones of Plasmodium falciparum. The in vitro antimalarial activity of pyronaridine was compared to activities of standard antimalarials against multidrug-resistant isolates of P. falciparum from eastern and northern Thailand using an assay based on the inhibition of schizont maturation. Isolates from eastern Thailand (n = 30) were susceptible to pyronaridine (IC50 8.40 nM), mefloquine (IC50 6.97 nM), and amodiaquine (IC50 12.7 nM) and resistant to chloroquine (IC50 361 nM), quinine (IC50 388 nM), and pyrimethamine (IC50 11,800 nM). The isolates from northern Thailand (n = 7) showed no statistical difference in susceptibility to pyronaridine (IC50 10.1 nM), amodiaquine (IC50 7.29 nM), and mefloquine (IC50 5.48 nM); however, isolates were significantly more susceptible to chloroquine (IC50 167 nM), quinine (IC50 248 nM), and pyrimethamine (IC50 1,980 nM). These data suggest a lack of cross-resistance between pyronaridine and either chloroquine, quinine, or pyrimethamine. Using the same assay system the in vitro activity of pyronaridine was evaluated against isolates from treatment failures of mefloquine or enpiroline from eastern Thailand. The IC50 values for mefloquine against five recrudescent isolates were significantly higher (IC50 16.4 nM) than the field isolates collected from the same region (IC50 6.97 nM); however, there was no significant difference in the pyronaridine susceptibility between the isolates from the field study (IC50 8.89 nM) and the isolates from the treatment failures (IC50 8.40 nM). These observations suggest a lack of cross-resistance to mefloquine following treatment failure with either mefloquine or enpiroline.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3277460

Childs, G E; Häusler, B; Milhous, W; Chen, C; Wimonwattrawatee, T; Pooyindee, N; Boudreau, E F

1988-01-01

37

Molecular Analysis of Mycobacterium avium Isolates by Using Pulsed-Field Gel Electrophoresis and PCR  

PubMed Central

Genetic relationships among 46 isolates of Mycobacterium avium recovered from 37 patients in a 2,500-bed hospital from 1993 to 1998 were assessed by pulsed-field gel electrophoresis (PFGE) and PCR amplification of genomic sequences located between the repetitive elements IS1245 and IS1311. Each technique enabled the identification of 27 to 32 different patterns among the 46 isolates, confirming that the genetic heterogeneity of M. avium strains is high in a given community. Furthermore, this retrospective analysis of sporadic isolates allowed us (i) to suggest the existence of two remanent strains in our region, (ii) to raise the question of the possibility of nosocomial acquisition of M. avium strains, and (iii) to document laboratory contamination. The methods applied in the present study were found to be useful for the typing of M. avium isolates. In general, both methods yielded similar results for both related and unrelated isolates. However, the isolates in five of the six PCR clusters were distributed among two to three PFGE patterns, suggesting that this PCR-based method may have limitations for the analysis of strains with low insertion sequence copy numbers or for resolution of extended epidemiologic relationships. PMID:10405383

Pestel-Caron, Martine; Graff, Gabriel; Berthelot, Gilles; Pons, Jean-Louis; Lemeland, Jean-Francois

1999-01-01

38

Comparison of Pseudomonas aeruginosa isolates from mink by serotyping and pulsed-field gel electrophoresis.  

PubMed

Isolates of Pseudomonas aeruginosa from clinical infections in mink were subjected to serotyping and pulsed-field gel electrophoresis (PFGE) using SpeI. A total of 212 isolates of P. aeruginosa from the year 1998 to 2001 were included in this study: 168 isolates from mink obtained from 74 farm outbreaks of haemorrhagic pneumonia. Isolates from mink were separated into 34 distinct clones by PFGE subtyping. All isolates from mink infected during the same farm outbreak were identical, except in one case where two different strains were isolated from mink obtained from the same farm outbreak. P. aeruginosa of specific PFGE types were found to cause clusters of outbreaks on several farms within a few weeks of each other. However, PFGE types of strains causing clusters of farm outbreaks changed from year to year. These results suggest that some outbreaks of haemorrhagic pneumonia are caused by pathogenic strains of P. aeruginosa spread between farms and animals either mechanically, or through feed or water from a common source, rather than by random nosocomial infections with strains from the farm environment. PMID:12814891

Hammer, Anne Sofie; Pedersen, Karl; Andersen, Thomas Holmen; Jørgensen, Jens Christian; Dietz, Hans Henrik

2003-07-17

39

The impact of a magnetic field on ferromagnetic materials isolated using ultraviolet laser ablation  

NASA Astrophysics Data System (ADS)

Laser ablation technology is used to isolate magnetic material to generate a local magnetic field effect. The impact of an induced magnetic field is enhanced by using the external magnetic field and can be widely employed to collect magnetic particles and position biomolecular in the bio-examination field. In addition, the magnetic field is affected and induced by the thermal stress produced after energy is exerted on the materials. Therefore, this study presents the phase of induced magnetic field (PIMF) of ferromagnetic film (Ni—1-?m thick) isolated using a 355-nm pulsed ultraviolet laser. In the experiment, three patterns comprising the following shapes and various isolated angle were designed for testing: hexagon (type I, 120°), L shape (type II, 90°), and cross shape (type III, 90°). The magnetic force microscopy image showed that when the isolating angle decreased, the PIMF increased, the value of which at the periphery of the corner of the type I and II patterns was -3.96° and -4.09°, respectively. In addition, by increasing the ablation time and residual thermal stress remaining in the material to increase the impact of the material's properties when laser scanning speed was reduced from 1,000 to 500 mm/s, the PIMF value increased from -4.09° to -5.82°. The PIMF value of the type III pattern increased to -9.87° because the residual thermal stress was twice that of the type II pattern. In the future, the experimental results can be used as a helpful reference for controlling magnetic particles in biomedical chips.

Tsai, Hsin-Yi; Yang, Ching Ching; Yang, Chih-Chung; Hsiao, Wen-Tse; Huang, Kuo-Cheng

2014-10-01

40

A new spiroplasma isolate from the field cricket (Gryllus bimaculatus) in Taiwan.  

PubMed

We briefly described the morphology and transmission pathway of a Spiroplasma sp. isolated from the field cricket, Gryllus bimaculatus in Taiwan, followed by the phylogenetic analysis based on the 16S rRNA gene sequence. The cricket spiroplasma infected the hemolymph, gut, muscle tissues and tracheal cells; therefore we suggest that the pathogen invaded tissues and organs from the hemolymph through the tracheal system and the endoplasmic reticular system. Based on 16S rRNA gene sequences and the phylogeny, this spiroplasma was most closely related to Spiroplasma platyhelix (Identity=95%) isolated from the dragonfly Pachydiplax longipennis and belongs to the Ixodetis clade. PMID:24801581

Nai, Yu-Shin; Su, Ping-Yi; Hsu, Yu-Hsiang; Chiang, Ching-Hao; Kim, Jae Su; Chen, Yue-Wen; Wang, Chung-Hsiung

2014-07-01

41

The genomic RNA1 and RNA2 sequences of the tobacco rattle virus isolates found in Polish potato fields.  

PubMed

Four tobacco rattle virus (TRV) isolates were identified from tobacco bait seedlings planted in soil samples from Polish potato fields. Sequence analysis of the genomic RNA1 of the isolates revealed significant similarity to the isolates Ho and AL recently found in Germany. Multiple sequence alignments of the genomic RNA2 indicated that the two isolates from northern Poland (Deb57 and Slu24) are in a cluster with the isolates PSG and PLB found in the Netherlands. The remaining two isolates, from central Poland (11r21 and Mlo7), are in a distinct group with the unique isolate SYM found in England. The RNA2 sequences of the studied isolates range from 1998 nt to 2739 nt in length, and all carry deletions of the 2b and/or 2c genes. The isolate Mlo7 has an atypical RNA2 structure, having its cp gene located in its central region. PMID:24637409

Yin, Zhimin; Pawe?kowicz, Magdalena; Michalak, Krystyna; Chrzanowska, Miros?awa; Zimnoch-Guzowska, Ewa

2014-06-24

42

Degradation of simazine by microorganisms isolated from soils of Spanish olive fields.  

PubMed

The capability of the microbial flora isolated from an olive field soil from Andalusia to mineralize simazine has been analyzed. From this soil, a group of bacteria capable of degrading 60 mg simazine litre(-1) in less than a week has been isolated. These microorganisms showed a low capacity for degrading this herbicide to carbon dioxide. When total DNA was isolated from this group of bacteria, we were able to detect by PCR the presence of only the atzC and the trzN genes. Some components of this bacterial population have been identified by sequencing of specific fragments from bacterial 16S rDNA, including Variovorax sp, Pseudoxanthomonas mexicana Thierry et al, Acidovorax sp and Methylopila capsulata Doronina et al. These data suggest that this consortium of bacteria performs an incomplete degradation of the simazine PMID:16007568

Santiago-Mora, Raquel; Martin-Laurent, Fabrice; de Prado, Rafael; Franco, Antonio R

2005-09-01

43

Bioremediation of hydrocarbon contaminated-oil field drill-cuttings with bacterial isolates  

Microsoft Academic Search

The effectiveness of 2 bacterial isolates (Bacillus subtilis and Pseudomonas aeruginosa) in the restoration of oil-field drill-cuttings contaminated with polycyclic aromatic hydrocarbons (PAHs) was studied. A mixture of 4 kg of the drill-cuttings and 0.67 kg of top-soil were charged into triplicate plastic reactors labeled A1 to A3, B1 to B3, C1 to C3 and O1 to O3. These were

Reuben N. Okparanma; Josiah M. Ayotamuno; Peremelade P. Arak

2009-01-01

44

Environmental factors affecting in vitro nitrogenase activity of cyanobacteria isolated from rice-fields  

Microsoft Academic Search

The nitrogen-fixing capacity of four cyanobacterial strains was tested in relation to heterotrophic ability, tolerance to combined nitrogen and adaptive capacity to changes in light intensity and pH. Strains (Anabaena variabilis UAM 202;Calothrix marchica UAM 214;Nodularia spumigena UAM 204,Nostoc punctiforme UAM 205) were isolated from the rice-fields of Valencia (Spain).C. marchica, was the only strain able to grow and to

Carlos Prosperi; Luis Boluda; Celina Luna; Eduardo Fernandez-Valiente

1992-01-01

45

Hy-wire and fast electric field change measurements near an isolated thunderstorm, appendix C  

NASA Technical Reports Server (NTRS)

Electric field measurements near an isolated thunderstorm at 6.4 km distance are presented from both a tethered balloon experiment called Hy-wire and also from ground based fast and slow electric field change systems. Simultaneous measurements were made of the electric fields during several lightning flashes at the beginning of the storm which the data clearly indicate were cloud-to-ground flashes. In addition to providing a comparison between the Hy-wire technique for measuring electric fields and more traditional methods, these data are interesting because the lightning flashes occurred prior to changes in the dc electric field, although Hy-wire measured changes in the dc field of up to 750 V/m in the direction opposite to the fair weather field a short time later. Also, the dc electric field was observed to decay back to its preflash value after each flash. The data suggest that Hy-wire was at the field reversal distance from this storm and suggest the charge realignment was taking place in the cloud with a time constant on the order of 20 seconds.

Holzworth, R. H.; Levine, D. M.

1983-01-01

46

Characterisation of macrocyclic lactone resistance in two field-derived isolates of Cooperia oncophora.  

PubMed

The anthelmintic sensitivity of two field-derived isolates (designated FI001 and FI004) of cattle nematodes from beef farms in Scotland were investigated in a controlled efficacy test (CET). Efficacies of ivermectin pour-on (IVM-PO), IVM injectable (IVM-INJ) and moxidectin pour-on (MOX-PO) formulations were assessed. In each group, five helminth-naïve calves were infected experimentally with 50,000 third stage larvae from either isolate and administered with anthelmintic at the manufacturers' recommended dose rate 28 days later. For each isolate, nematode burdens were compared between treatment and control groups to determine efficacy. Nematode species composition, based on data derived from the untreated control groups' burden estimations, were 39 and 14% Cooperia oncophora and 61 and 86% Ostertagia ostertagi for isolates FI001 and FI004, respectively. Macrocyclic lactone resistance in C. oncophora was confirmed for both FI001 and FI004 isolates. Efficacies (as determined by nematode burden analysis) of 4, 21 and 31% for FI001, and 10, 1 and 74% for FI004, were obtained for IVM-INJ, IVM-PO and MOX-PO, respectively. Efficacy based on faecal egg count reduction at seven days post anthelmintic administration were 8, 99 and 100% for FI001, and 37, 20 and 100% for FI004 for IVM-INJ, IVM-PO and MOX-PO, respectively. In summary, this study details two macrocyclic lactone resistant isolates of C. oncophora obtained from cattle from two distinct geographical locales in the UK. PMID:22884912

Bartley, D J; McArthur, C L; Devin, L M; Sutra, J F; Morrison, A A; Lespine, A; Matthews, J B

2012-12-21

47

Detection and Isolation Techniques for Methanogens from Microbial Mats (in the El Tatio Geyser Field, Chile)  

NASA Astrophysics Data System (ADS)

Isolating methanogenic archea from an extreme environment such as El Tatio (high altitude, arid climate) gives insight to the methanogenic taxas able to adapt and grow under extreme conditions. The hydrothermal waters at El Tatio geyser field demonstrate extreme geochemical conditions, with discharge water from springs and geysers at local boiling temperature (85° C) with high levels of arsenic and low DIC levels. Despite these challenges, many of El Tatio’s hundred plus hydrothermal features host extensive microbial mat communities, many showing evidence of methanogenesis. When trying to isolate methanogens unique to this area, various approaches and techniques were used. To detect the presence of methanogens in samples taken from the field, dissolved methane concentrations were determined via gas chromatography (GC) analysis. Samples were then selected for culturing and most probable number (MPN) enumeration, where growth was assessed using both methane production and observations of fluorescence under UV light. PCR was used to see if the archeal DNA was apparent directly from the field, and shotgun cloning was done to determine phylogenetic affiliation. Several culturing techniques were carried out in an attempt to isolate methanogens from samples that showed evidence of methanogenesis. The slant culturing method was used because of the increased surface area for colonization combined with the relative ease of keeping anaerobic. After a few weeks, when colonies were apparent, some were aseptically selected and inoculated to observe growth in a liquid media containing ampicillin to inhibit bacterial growth. Culturing techniques proved successful after inoculation, showing a slow growth of methanogens via GC and autofluorescence. Further PCR tests and subsequent sequencing were done to confirm and identify isolates.

Pearson, E. Z.; Franks, M. A.; Bennett, P.

2010-12-01

48

Device Isolation in Hybrid Field-Effect Transistors by Semiconductor Micropatterning Using Picosecond Lasers  

NASA Astrophysics Data System (ADS)

A solid-state picosecond laser is used to ablate semiconductor thin films in spatially localized areas, providing an alternative to device isolation strategies based on chemical or ion etching techniques. Field-effect transistors (FETs) of emerging organic and inorganic materials often utilize a continuous semiconductor film and an array of top-contact electrodes. Electrically isolating individual FET components from other circuit elements is essential in order to reduce parasitic capacitances and unwanted current pathways, both to improve device performance and to enable the observation of new or enhanced physical phenomena. We pattern FET arrays with ultrafast-pulse-duration (1.5 ps) and low-fluence (0.09 J cm-2) optical pulses using the fundamental wavelength (1030 nm) of an Yb-YAG laser. We investigate two representative semiconductor materials. First, zinc oxide (ZnO) is deposited onto Si /SiO2 substrates by sol-gel methods and used to create n-channel FETs with aluminum top electrodes. Isolation of individual FETs enables the clear observation of photomodulation of the FET device parameters via photoinduced electron donation from an adsorbed chromophore. The second system comprises thin-film bilayers of tellurium and organic semiconductor molecules sequentially vapor-deposited onto Si /SiO2 substrates, with gold electrodes deposited last. Charge carrier mobility is maintained for devices isolated by picosecond lasers, but leakage currents through the FET dielectric are drastically reduced.

Ireland, Robert M.; Liu, Yu; Spalenka, Josef W.; Jaiswal, Supriya; Fukumitsu, Kenshi; Oishi, Shingo; Saito, Hiroshi; Ryosuke, Mochizuki; Evans, Paul G.; Katz, Howard E.

2014-10-01

49

Field studies on two rock phosphate solubilizing actinomycete isolates as biofertilizer sources  

NASA Astrophysics Data System (ADS)

Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively. The beneficial effects of the microbial organic fertilizer are discussed. Justification for more intensive research on rock phosphate organic fertilizer is highlighted.

Mba, Caroline C.

1994-03-01

50

Generation of isolated sub-10-attosecond pulses in spatially inhomogenous two-color fields.  

PubMed

We present a theoretical investigation of high-order harmonic generation in spatially inhomogeneous two-color laser fields by solving three dimensional time dependent Schrödinger equation. The cutoff in the harmonic spectra can be significantly extended by means of our proposed method (i.e., from helium interacting with the plasmon-enhanced two-color laser fields), and an ultrabroad supercontinuum up to 1.5 keV is generated by selecting proper carrier-envelope phase of the controlling field. Moreover, classical trajectory extraction, time-dependent ionization and recombination rates, and time-frequency analyses are used to explain the generation of this ultrabroadband supercontinuum. As a result, an isolated 8.8 attosecond pulse can be generated directly by the superposition of the supercontinuum harmonics. PMID:25401647

Cao, Xu; Jiang, Shicheng; Yu, Chao; Wang, Yunhui; Bai, Lihua; Lu, Ruifeng

2014-10-20

51

First clinical isolates of Cronobacter spp. (Enterobacter sakazakii) in Argentina: characterization and subtyping by pulsed-field gel electrophoresis.  

PubMed

Cronobacter species are opportunistic pathogens associated with severe infections in neonates and immunocompromised infants. From January 2009 through September 2010, two cases of neonatal infections associated with Cronobacter malonaticus and one case associated with Cronobacter sakazakii, two of them fatal, were reported in the same hospital. These are the first clinical isolates of Cronobacter spp. in Argentina. The objective of this work was to characterize and subtype clinical isolates of Cronobacter spp. in neonate patients, as well as to establish the genetic relationship between these isolates and the foodborne isolates previously identified in the country. Pulsed-field gel electrophoresis analysis showed a genetic relationship between the C. malonaticus isolates from two patients. Different results were found when the pulsed-field gel electrophoresis patterns of clinical isolates were compared with those deposited in the National Database of Cronobacter spp. PMID:24165138

Asato, Valeria C; Vilches, Viviana E; Pineda, María G; Casanueva, Enrique; Cane, Alejandro; Moroni, Mirian P; Brengi, Silvina P; Pichel, Mariana G

2013-01-01

52

Near-field Holographic Retrieval of an Isolated Subwavelength Hole in a Thin Metallic Film  

E-print Network

Using a holographic approach, we experimentally study the near-field intensity distribution of light squeezed through an isolated subwavelength plasmonic hole in a thin metallic film. Our experiments revealed an in-plane electric dipole moment excited near the isolated hole. By analyzing the fringe patterns formed between the in-plane dipole and plane wave illumination, both the transmission coefficient and phase shift of the dipole can be retrieved. We also observed opposite phases of the excited dipoles from the subwavelength dent and protrusion in the metallic film, in good agreement with the prediction from our model. Our approach can be used to study the microscopic process of the light-structure interaction for the plasmonic and nanophotonic systems with potential applications in high density optical data storages.

Xu, Jun; Fang, Nicholas X

2014-01-01

53

Sequence conservation in field and experimental isolates of Borna disease virus.  

PubMed Central

Coding and noncoding sequences were analyzed from field and experimental isolates of Borna disease virus. For a 24-kDa protein, maximum divergence was 1.5% at the predicted amino acid level and 3.1% at the nucleotide level. For a 40-kDa protein, maximum divergence was 1.1% at the predicted amino acid level and 4.1% at the nucleotide level. The highest variability in sequence (10%) was found in a 40-nucleotide stretch of genomic RNA between coding sequences for the 40- and 24-kDa proteins. The degree of sequence conservation in these isolates, passaged in various host species in vivo and in vitro over a period of 64 years, is unusual for negative-strand RNA viruses. PMID:8254777

Schneider, P A; Briese, T; Zimmermann, W; Ludwig, H; Lipkin, W I

1994-01-01

54

Breakdown characteristics of an isolated conducting object in a uniform electric field  

NASA Technical Reports Server (NTRS)

A laboratory experiment was conducted to determine the physical processes involved in the electrical breakdown of a particular spark gap arrangement. The gap consists of an isolated conducting ellipsoid located midway between two large flat electrodes. Gradual increase of the applied electric field, E, in the gap produces corona on the ellipsoid tips followed by flashover in a leader-arc sequence. The leader phase consists of the abrupt formation of ionized channels which partially bridge the gap and then decay prior to the arc. Measurements of dE/dt and of current were made, and photographs were taken with an image converter. Experimental parameters are listed.

Grothaus, M. G.; Trost, T. F.

1986-01-01

55

[Wind tunnel experiment on canopy structural parameters of isolated tree and wind velocity field characters nearby].  

PubMed

The canopy structural parameters(porosity beta and permeability alpha) of isolated tree, and the wind velocity field character nearby were analyzed by wind tunnel experiment. The results show that alpha and beta fitted the function of alpha = beta 0.6, and the wind velocity nearby decreased in ellipsoid contour. The contour increased with increasing tree height and canopy width, and decreased with increasing permeability (or porosity). The isotach became the shape of ellipses or elliptic segments in horizontal and vertical plans. PMID:11767595

Guan, D; Zhu, T

2000-04-01

56

Comparison of Haemophilus parasuis reference strains and field isolates by using random amplified polymorphic DNA and protein profiles  

PubMed Central

Background Haemophilus parasuis is the causative agent of Glässer’s disease and is a pathogen of swine in high-health status herds. Reports on serotyping of field strains from outbreaks describe that approximately 30% of them are nontypeable and therefore cannot be traced. Molecular typing methods have been used as alternatives to serotyping. This study was done to compare random amplified polymorphic DNA (RAPD) profiles and whole cell protein (WCP) lysate profiles as methods for distinguishing H. parasuis reference strains and field isolates. Results The DNA and WCP lysate profiles of 15 reference strains and 31 field isolates of H. parasuis were analyzed using the Dice and neighbor joining algorithms. The results revealed unique and reproducible DNA and protein profiles among the reference strains and field isolates studied. Simpson’s index of diversity showed significant discrimination between isolates when three 10mer primers were combined for the RAPD method and also when both the RAPD and WCP lysate typing methods were combined. Conclusions The RAPD profiles seen among the reference strains and field isolates did not appear to change over time which may reflect a lack of DNA mutations in the genes of the samples. The recent field isolates had different WCP lysate profiles than the reference strains, possibly because the number of passages of the type strains may affect their protein expression. PMID:22703293

2012-01-01

57

Molecular characteristics of Polish field strains of Marek's disease herpesvirus isolated from vaccinated chickens  

PubMed Central

Background Twenty-nine Marek's disease virus (MDV) strains were isolated during a 3 year period (2007-2010) from vaccinated and infected chicken flocks in Poland. These strains had caused severe clinical symptoms and lesions. In spite of proper vaccination with mono- or bivalent vaccines against Marek's disease (MD), the chickens developed symptoms of MD with paralysis. Because of this we decided to investigate possible changes and mutations in the field strains that could potentially increase their virulence. We supposed that such mutations may have been caused by recombination with retroviruses of poultry - especially reticuloendotheliosis virus (REV). Methods In order to detect the possible reasons of recent changes in virulence of MDV strains, polymerase chain reaction (PCR) analyses for meq oncogene and for long-terminal repeat (LTR) region of REV were conducted. The obtained PCR products were sequenced and compared with other MDV and REV strains isolated worldwide and accessible in the GeneBank database. Results Sequencing of the meq oncogene showed a 68 basepair insertion and frame shift within 12 of 24 field strains. Interestingly, the analyses also showed 0.78, 0.8, 0.82, 1.6 kb and other random LTR-REV insertions into the MDV genome in 28 of 29 of strains. These genetic inserts were present after passage in chicken embryo kidney cells suggesting LTR integration into a non-functional region of the MDV genome. Conclusion The results indicate the presence of a recombination between MDV and REV under field conditions in Polish chicken farms. The genetic changes within the MDV genome may influence the virus replication and its features in vivo. However, there is no evidence that meq alteration and REV insertions are related to the strains' virulence. PMID:21320336

2011-01-01

58

Pulsed-field gel electrophoresis for isolation of full-length phytoplasma chromosomes from plants.  

PubMed

Pulsed-field gel electrophoresis (PFGE) is a powerful technique for genomic studies of unculturable plant-pathogenic phytoplasmas, which enables separation of full-length phytoplasma chromosomes from contaminating host plant nucleic acids. The PFGE method described here involves isolation of phytoplasmal DNA from high-titer phytoplasma-infected herbaceous plants using a phytoplasma enrichment procedure, embedding of phytoplasma chromosomes in agarose blocks, and separation of entire phytoplasma chromosomes from contaminating host plant nucleic acids by electrophoresis. Full-length phytoplasma chromosomes are resolved as single, discrete bands in the gel. The identity of these bands can be confirmed by Southern blot hybridization using a ribosomal DNA fragment as a probe. The method does not utilize gamma-irradiation to linearize phytoplasma chromosomes prior to electrophoresis. PMID:22987433

Marcone, Carmine

2013-01-01

59

Isolation and identification of a lethal rhabdovirus from farmed rice field eels Monopterus albus.  

PubMed

We provide the first description of a virus responsible for a systemic hemorrhagic disease causing high mortality in farmed rice field eels Monopterus albus in China. Typical signs exhibited by the diseased fish were extensive hemorrhages in the skin and viscera and some neurological signs, such as loss of equilibrium and disorganized swimming. Histopathological examination revealed various degrees of necrosis within the spleen and liver. Virus isolation was attempted from visceral tissues of diseased fish by inoculation on 6 fish cell lines. Typical cytopathic effects (CPE) were produced in bluegill fry (BF2) cells, so this cell line was chosen for further isolation and propagation of the virus. Electron microscopy observation showed that the negative stained viral particles had the characteristic bullet shape of rhabdoviruses and an estimated size of 60 × 120 nm. We therefore tentatively refer to this virus as Monopterus albus rhabdovirus (MoARV). Molecular characterization of MoARV, including sequence analysis of the nucleoprotein (N), phosphoprotein (P), and glycoprotein (G) genes, revealed 94.5 to 97.3% amino acid similarity to that of Siniperca chuatsi rhabdovirus. Phylogenetic analysis based on the amino acid sequences of N and G proteins indicated that MoARV should be a member of the genus Vesiculovirus. Koch's postulates were fulfilled by infecting healthy rice field eels with MoARV, which produced an acute infection. RT-PCR analysis demonstrated that MoARV RNA could be detected in both naturally and experimentally infected fish. The data suggest that MoARV was the causative pathogen of the disease. PMID:24191997

Ou, Tong; Zhu, Ruo-Lin; Chen, Zhong-Yuan; Zhang, Qi-Ya

2013-11-01

60

De Novo Assembly of a Field Isolate Genome Reveals Novel Plasmodium vivax Erythrocyte Invasion Genes  

PubMed Central

Recent sequencing of Plasmodium vivax field isolates and monkey-adapted strains enabled characterization of SNPs throughout the genome. These analyses relied on mapping short reads onto the P. vivax reference genome that was generated using DNA from the monkey-adapted strain Salvador I. Any genomic locus deleted in this strain would be lacking in the reference genome sequence and missed in previous analyses. Here, we report de novo assembly of a P. vivax field isolate genome. Out of 2,857 assembled contigs, we identify 362 contigs, each containing more than 5 kb of contiguous DNA sequences absent from the reference genome sequence. These novel P. vivax DNA sequences account for 3.8 million nucleotides and contain 792 predicted genes. Most of these contigs contain members of multigene families and likely originate from telomeric regions. Interestingly, we identify two contigs containing predicted protein coding genes similar to known Plasmodium red blood cell invasion proteins. One gene encodes the reticulocyte-binding protein gene orthologous to P. cynomolgi RBP2e and P. knowlesi NBPXb. The second gene harbors all the hallmarks of a Plasmodium erythrocyte-binding protein, including conserved Duffy-binding like and C-terminus cysteine-rich domains. Phylogenetic analysis shows that this novel gene clusters separately from all known Plasmodium Duffy-binding protein genes. Additional analyses showing that this gene is present in most P. vivax genomes and transcribed in blood-stage parasites suggest that P. vivax red blood cell invasion mechanisms may be more complex than currently understood. The strategy employed here complements previous genomic analyses and takes full advantage of next-generation sequencing data to provide a comprehensive characterization of genetic variations in this important malaria parasite. Further analyses of the novel protein coding genes discovered through de novo assembly have the potential to identify genes that influence key aspects of P. vivax biology, including alternative mechanisms of human erythrocyte invasion. PMID:24340114

Hester, James; Chan, Ernest R.; Menard, Didier; Mercereau-Puijalon, Odile; Barnwell, John; Zimmerman, Peter A.; Serre, David

2013-01-01

61

Chlorhexidine Digluconate Effects on Planktonic Growth and Biofilm Formation in Some Field Isolates of Animal Bacterial Pathogens  

PubMed Central

Background: To study chlorhexidine digluconate disinfectant effects on planktonic growth and biofilm formation in some bacterial field isolates from animals. Objectives: The current study investigated chlorhexidine digluconate effects on planktonic growth and biofilm formation in some field isolates of veterinary bacterial pathogens. Materials and Methods: Forty clinical isolates of Escherichia coli, Salmonella serotypes, Staphylococcus. aureus and Streptococcus agalactiae (10 isolates for each) were examined for chlorhexidine digluconate effects on biofilm formation and planktonic growth using microtiter plates. In all of the examined strains in the presence of chlorhexidine digluconate, biofilm development and planktonic growth were affected at the same concentrations of the disinfectant. Results: Chlorhexidine digluconate inhibited the planktonic growth of different bacterial species at sub-MICs. But they were able to induce biofilm development of the E. coli, Salmonella spp., S. aureus and Str. agalactiae strains. Conclusions: Bacterial resistance against chlorhexidine is increasing. Sub-MIC doses of chlorhexidine digluconate can stimulate the formation of biofilm strains. PMID:24872940

Ebrahimi, Azizollah; Hemati, Majid; Habibian Dehkordi, Saeed; Bahadoran, Shahab; Khoshnood, Sheida; Khubani, Shahin; Dokht Faraj, Mahdi; Hakimi Alni, Reza

2014-01-01

62

Paenibacillus ginsengisoli sp. nov., a novel bacterium isolated from soil of a ginseng field in Pocheon province, South Korea  

Microsoft Academic Search

A Gram-positive, aerobic or facultative anaerobic, motile, spore-forming bacterial strain, designated Gsoil 1638T, was isolated from a soil sample of a ginseng field in Pocheon province (South Korea), and was characterized taxonomically\\u000a by using a polyphasic approach. It grew well on nutrient agar medium, utilized a fairly narrow spectrum of carbon sources\\u000a and tolerated 10% NaCl. The isolate was positive

Myungjin Lee; Leonid N. Ten; Sang-Hoon Baek; Wan-Taek Im; Zubair Aslam; Sung-Taik Lee

2007-01-01

63

Assessment of Southern blot ribotyping for differentiation of Leptospira strains isolated from field rats.  

PubMed

A Southern blot ribotyping based on EcoRV and HindIII digestion with two 16S and 23S rDNA probes for differentiating 27 Leptospira serovars was developed. The results between ribotyping and serotyping among 40 leptospiral strains isolated from field rats trapped in the northeastern region of Thailand during 1999-2000, were compared. A combination of Southern blot ribotyping, using EcoRV or HindIII digestion with both 16S and 23S rDNA as the probes, successfully typed 27 Leptospira serovars into 24 ribotypes with the discriminatory index (D) values of 0.99. The 16S- and 23S-EcoRV ribopatterns produced 17 and 9 profiles, respectively, with D values of 0.95 and 0.63, respectively. Ribopatterns of HindIII from both specific probes yielded 17 patterns. The D values of 16S- and 23S-HindIII ribopatterns were 0.94 and 0.93, respectively. With EcoRV digestion, the 16S rDNA probe was more discriminative than the 23S rDNA probe for differentiating Leptospira serovars. Moreover, the 16S-EcoRV (11 profiles), 16S-HindIII (11 profiles), and 23S-HindIII (10 profiles) ribopatterns produced higher numbers of distinct and unique profiles than the 23S-EcoRV (5 profiles). The results showed 100% concordance between ribotyping and serotyping, leading to all 40 isolates being successfully typed. The current study revealed that ribotyping as a quick and powerful tool for differentiating Leptospira serovars, has potential value in epidemiological studies. PMID:17346835

Kositanont, Uraiwan; Chotinantakul, Kamonnaree; Phulsuksombati, Duangporn; Tribuddharat, Chanwit

2007-05-01

64

Plasmodium falciparum Field Isolates Commonly Use Erythrocyte Invasion Pathways That Are Independent of Sialic Acid Residues of Glycophorin A  

PubMed Central

Erythrocyte invasion by malaria parasites is mediated by specific molecular interactions. Sialic acid residues of glycophorin A are used as invasion receptors by Plasmodium falciparum. In vitro invasion studies have demonstrated that some cloned P. falciparum lines can use alternate receptors independent of sialic acid residues of glycophorin A. It is not known if invasion by alternate pathways occurs commonly in the field. In this study, we used in vitro growth assays and erythrocyte invasion assays to determine the invasion phenotypes of 15 P. falciparum field isolates. Of the 15 field isolates tested, 5 multiply in both neuraminidase and trypsin-treated erythrocytes, 3 multiply in neuraminidase-treated but not trypsin-treated erythrocytes, and 4 multiply in trypsin-treated but not neuraminidase-treated erythrocytes; 12 of the 15 field isolates tested use alternate invasion pathways that are not dependent on sialic acid residues of glycophorin A. Alternate invasion pathways are thus commonly used by P. falciparum field isolates. Typing based on two polymorphic markers, MSP-1 and MSP-2, and two microsatellite markers suggests that only 1 of the 15 field isolates tested contains multiple parasite genotypes. Individual P. falciparum lines can thus use multiple invasion pathways in the field. These observations have important implications for malaria vaccine development efforts based on EBA-175, the P. falciparum protein that binds sialic acid residues of glycophorin A during invasion. It may be necessary to target parasite ligands responsible for the alternate invasion pathways in addition to EBA-175 to effectively block erythrocyte invasion by P. falciparum. PMID:10531229

Okoyeh, Jude Nnaemeka; Pillai, C. R.; Chitnis, Chetan E.

1999-01-01

65

Field Studies Reveal Strong Postmating Isolation between Ecologically Divergent Butterfly Populations  

PubMed Central

Gene flow between populations that are adapting to distinct environments may be restricted if hybrids inherit maladaptive, intermediate phenotypes. This phenomenon, called extrinsic postzygotic isolation (EPI), is thought to play a critical role in the early stages of speciation. However, despite its intuitive appeal, we know surprisingly little about the strength and prevalence of EPI in nature, and even less about the specific phenotypes that tend to cause problems for hybrids. In this study, we searched for EPI among allopatric populations of the butterfly Euphydryas editha that have specialized on alternative host plants. These populations recall a situation thought typical of the very early stages of speciation. They lack consistent host-associated genetic differentiation at random nuclear loci and show no signs of reproductive incompatibility in the laboratory. However, they do differ consistently in diverse host-related traits. For each of these traits, we first asked whether hybrids between populations that use different hosts (different-host hybrids) were intermediate to parental populations and to hybrids between populations that use the same host (same-host hybrids). We then conducted field experiments to estimate the effects of intermediacy on fitness in nature. Our results revealed strong EPI under field conditions. Different-host hybrids exhibited an array of intermediate traits that were significantly maladaptive, including four behaviors. Intermediate foraging height slowed the growth of larvae, while intermediate oviposition preference, oviposition site height, and clutch size severely reduced the growth and survival of the offspring of adult females. We used our empirical data to construct a fitness surface on which different-host hybrids can be seen to fall in an adaptive valley between two peaks occupied by same-host hybrids. These findings demonstrate how ecological selection against hybrids can create a strong barrier to gene flow at the early stages of adaptive divergence. PMID:21048982

McBride, Carolyn S.; Singer, Michael C.

2010-01-01

66

Field studies reveal strong postmating isolation between ecologically divergent butterfly populations.  

PubMed

Gene flow between populations that are adapting to distinct environments may be restricted if hybrids inherit maladaptive, intermediate phenotypes. This phenomenon, called extrinsic postzygotic isolation (EPI), is thought to play a critical role in the early stages of speciation. However, despite its intuitive appeal, we know surprisingly little about the strength and prevalence of EPI in nature, and even less about the specific phenotypes that tend to cause problems for hybrids. In this study, we searched for EPI among allopatric populations of the butterfly Euphydryas editha that have specialized on alternative host plants. These populations recall a situation thought typical of the very early stages of speciation. They lack consistent host-associated genetic differentiation at random nuclear loci and show no signs of reproductive incompatibility in the laboratory. However, they do differ consistently in diverse host-related traits. For each of these traits, we first asked whether hybrids between populations that use different hosts (different-host hybrids) were intermediate to parental populations and to hybrids between populations that use the same host (same-host hybrids). We then conducted field experiments to estimate the effects of intermediacy on fitness in nature. Our results revealed strong EPI under field conditions. Different-host hybrids exhibited an array of intermediate traits that were significantly maladaptive, including four behaviors. Intermediate foraging height slowed the growth of larvae, while intermediate oviposition preference, oviposition site height, and clutch size severely reduced the growth and survival of the offspring of adult females. We used our empirical data to construct a fitness surface on which different-host hybrids can be seen to fall in an adaptive valley between two peaks occupied by same-host hybrids. These findings demonstrate how ecological selection against hybrids can create a strong barrier to gene flow at the early stages of adaptive divergence. PMID:21048982

McBride, Carolyn S; Singer, Michael C

2010-01-01

67

Studies on the bacteria isolated anaerobically from paddy field soil III. Production of fatty acids and ammonia by Clostridium species  

Microsoft Academic Search

The volatile fatty acids produced by the representative strains of clostridia isolated from paddy field soil were surveyed. All the strains, except Cl. tertium, utilized only amino acids as the sole source of energy for growth. All of them produced acetic and butyric acids, and some of them produced propionic acid in addition. Iso-valeric and iso-butyric acids were also produced,

Kiyoshi Takeda; Choseki Furusaka

1975-01-01

68

Reaction of Brassica juncea (Indian Mustard) Lines to Australian Isolates of Leptosphaeria maculans under Glasshouse and Field Conditions  

Microsoft Academic Search

Brassica juncea (Indian mustard) lines from diverse geographical locations around the world and from Australian breeding programs were screened for resistance to the blackleg fungus, Leptosphaeria maculans, in both glasshouse and field trials. The five Australian L. maculans isolates used in glasshouse trials could be classified into two groups; those that attacked all B. juncea lines, and those that attacked

Agus Purwantara; Phillip A. Salisbury; Wayne A. Burton; Barbara J. Howlett

1998-01-01

69

Complete genome sequence of an Indian field isolate of classical Swine Fever virus belonging to subgenotype 1.1.  

PubMed

We report the complete genome sequence of an Indian field isolate of classical swine fever virus (CSFV) belonging to predominant subgenotype 1.1 prevalent in India. This report will help in understanding the molecular diversity of CSFV strains circulating worldwide and to select and develop a suitable vaccine candidate for classical swine fever (CSF) control in India. PMID:25278522

Kamboj, Aman; Patel, Chhabi L; Chaturvedi, V K; Saini, Mohini; Gupta, Praveen K

2014-01-01

70

Brevibacillus ginsengisoli sp. nov., a denitrifying bacterium isolated from soil of a ginseng field.  

PubMed

A Gram-positive, rod-shaped, spore-forming bacterium, Gsoil 3088T, was isolated from soil from a ginseng field in Pocheon Province in South Korea and characterized in order to determine its taxonomic position. On the basis of 16S rRNA gene sequence similarity, strain Gsoil 3088T was shown to belong to the family Paenibacillaceae, being related to Brevibacillus centrosporus (96.6%), Brevibacillus borstelensis (96.3%), Brevibacillus parabrevis (96.1%), Brevibacillus formosus (96.1%), Brevibacillus brevis (96.1%) and Brevibacillus laterosporus (96.0%). The phylogenetic distances from other validly described species within the genus Brevibacillus were greater than 4.0% (i.e. there was less than 96.0% similarity). The G+C content of the genomic DNA was 52.1 mol%. Phenotypic and chemotaxonomic data (major menaquinone, MK-7; fatty acid profile, iso-C15:0, iso-C14:0 and anteiso-C15:0) supported the affiliation of strain Gsoil 3088T to the genus Brevibacillus. The results of physiological and biochemical tests allowed strain Gsoil 3088T to be distinguished genotypically and phenotypically from Brevibacillus species with validly published names. Strain Gsoil 3088T, therefore, represents a novel species of the genus Brevibacillus, for which the name Brevibacillus ginsengisoli sp. nov. is proposed. The type strain is Gsoil 3088T (=KCTC 13938T=LMG 23403T). PMID:17082408

Baek, Sang-Hoon; Im, Wan-Taek; Oh, Hyun Woo; Lee, Jung-Sook; Oh, Hee-Mock; Lee, Sung-Taik

2006-11-01

71

Agromyces arachidis sp. nov. Isolated from a Peanut (Arachis hypogaea) Crop Field  

PubMed Central

A Gram-positive, yellowish bacterium strain AK-1T was isolated from soil sample collected from peanut (Arachis hypogaea) crop field and studied by using a polyphasic approach. The organism had morphological and chemotaxonomic properties consistent with its classification in the genus Agromyces. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain AK-1T was closely related to Agromyces aurantiacus (98.6%) followed by Agromyces soli (98.3%), Agromyces tropicus (97.6%), Agromyces ulmi (97.3%), Agromyces flavus (97.2%), and Agromyces italicus (97.0%), whereas the sequence similarity values with respect to the other Agromyces species with validly published names were between 95.3 and 96.7?%. However, the DNA-DNA hybridization values obtained between strain AK-1T and other related strains were well below the threshold that is required for the proposal of a novel species. The DNA G + C content of the strain is 71.8?mol%. The above data in combination with the phenotypic distinctiveness of AK-1T clearly indicate that the strain represents a novel species, for which the name Agromyces arachidis sp. nov. is proposed. The type strain is AK-1T (=MTCC 10524T = JCM 19251T). PMID:24348566

Kaur, Chandandeep; Pinnaka, Anil Kumar; Singh, Nitin Kumar; Bala, Monu

2013-01-01

72

Laboratory and field evaluation of selective media for isolation of group B streptococci.  

PubMed Central

Problems encountered with currently recommended selective media for group B streptococci (GBS) (selective broth medium and CNA agar) prompted a searach for alternative culture methods in ongoing epidemiological studies. Previously recommended inhibitory agents were tested in vitro. Gentamicin, alone or in combination with nalidixic acid, proved inhibitory for many GBS strains. Among other agents tested, polymyxin was most complementary to the gram-negative spectrum of nalidixic acid, without compromising GBS growth. Crystal violet provided the simplest, most economical staphylococcal inhibitor. Broth and agar media, constituted with these three agents and designated NPC, were evaluated in vitro and in field studies. This investigation represents the first direct comparison of broth media containing inhibitory agents for the preferential isolation of GBS. In maternal colonization studies, NPC broth proved superior to Todd-Hewitt broth containing nalidixic acid and gentamicin at concentrations employed in the previously described selective broth medium (95% versus 59% recovery). Our comparisons were done without added sheep blood since GBS grow well in Todd-Hewitt broth. NPC broth proved more sensitive than NPC agar for detecting GBS colonization in newborns. The NPC agar medium was useful for further purification of broth cultures and quantitative culture techniques. PMID:379037

Gray, B M; Pass, M A; Dillon, H C

1979-01-01

73

Isolated thermal neutron stars, SGRs and AXPs: propellers and early accretors with conventional magnetic fields?  

E-print Network

The similarity of rotation periods from three interesting classes of neutron stars, the anomalous X-ray pulsars (AXPs), the soft gamma ray repeaters (SGRs) and the dim isolated thermal neutron stars (DTNs) suggests a common mechanism with an asymptotic spindownphase, extending through the propeller and early accretion stages. The DTNs are interpreted as sources in the propeller stage. Their low luminosities arise from frictional heating in the neutron star. SGRs and AXPs are accreting at $\\dot{M} \\sim 10^{15} gm/s $. The limited range of near equilibrium periods corresponds to a limited range of mass inflow rates $\\dot{M}$. For lower rates the source of mass inflow may be depleted before the asymptotic stage is reached, while sources with higher $\\dot{M}$ or later ages possess circumstellar material that is optically thick to electron scattering, destroying the X-ray beaming and the modulation at the rotation period. The model works with conventional magnetic fields of 10$^{11}-10^{12}$ G, obviating the need to postulate magnetars. Frequently sampled timing observations of AXPs, SGRs and DTNs can distinguish between this explanation and the magnetar model.

M. Ali Alpar

1999-12-10

74

Paludibacter jiangxiensis sp. nov., a strictly anaerobic, propionate-producing bacterium isolated from rice paddy field.  

PubMed

A mesophilic, obligately anaerobic, propionate-producing fermentative bacterium, designated strain NM7(T), was isolated from rural rice paddy field. Cells of strain NM7(T) are Gram-negative, non-motile, non-spore-forming, short rods, and negative for catalase. The strain grew optimally at 37 °C (the range for growth 15-40 °C) and pH 7.0 (pH 5.0-7.5). The strain could grow fermentatively on various sugars, including arabinose, xylose, fructose, galactose, glucose, mannose, cellobiose, lactose, maltose, sucrose, pectin and starch. The main end products of glucose fermentation were acetate and propionate. Yeast extract was not required but stimulated the growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite, and Fe(III) nitrilotriacetate were not used as terminal electron acceptors. The G+C content of genomic DNA was 42.8 mol%. The major cellular fatty acids were C15:0, anteiso-C15:0, C16:0, and C17:0. The most abundant polar lipid of strain NM7(T) was phosphatidylethanolamine. 16S rRNA gene sequence analysis revealed that it belongs to the family Porphyromonadaceae of the phylum Bacteroidetes. The closest recognized species was Paludibacter propionicigenes (91.4 % similarity in 16S rRNA gene sequence). A novel species, Paludibacter jiangxiensis sp. nov., is proposed to accommodate strain NM7(T) (=JCM 17480(T) = CGMCC 1.5150(T) = KCTC 5844(T)). PMID:24419224

Qiu, Yan-Ling; Kuang, Xiao-Zhu; Shi, Xiao-Shuang; Yuan, Xian-Zheng; Guo, Rong-Bo

2014-03-01

75

Arthrobacter ginsengisoli sp. nov., isolated from soil of a ginseng field.  

PubMed

A Gram-staining-positive, catalase-positive, oxidase-negative, non-motile, non-flagellate and rod-shaped bacterium, was designated as DCY81(T), and isolated from soil of a ginseng field in Pocheon province, Republic of Korea. The 16S rRNA gene sequence analysis revealed that strain DCY81(T) belonged to the genus Arthrobacter. Major fatty acid was anteiso-C15:0, while major polar lipids were diphosphatidyglycerol, phatidyglycerol, phosphatidylinositol, monogalactosyldiacylglycerol (GL1), and dimannosyldiacylglycerol (GL2). The dominant quinone was MK-9(H2). The peptidoglycan type was A3? with an L-Lys-L-Ala-L-Thr-L-Ala interpeptide bridge. The DNA-DNA hybridization relatedness between strain DCY81(T) and Arthrobacter siccitolerans LMG 27359(T) (98.2 %), Arthrobacter sulfonivorans JCM 13520(T) (97.81 %), Arthrobacter scleromae DSM 17756(T) (97.59 %), Arthrobacter oxydans KCTC 3383(T) (97.3 %) was 39.1 ± 0.2, 62.2 ± 1.6, 36.8 ± 1.1 and 48.3 ± 1.6 %, respectively which show that the genotypic separation of strain DCY81(T) from the closest reference strain of the genus Arthrobacter. The DNA G+C content was 65.2 mol%. The genotypic analysis, physiological, and chemotaxonomic results indicate that strain DCY81(T) represents a novel species of the genus Arthrobacter. Therefore, Arthrobacter ginsengisoli sp. nov., is proposed as the type strain (=KCTC 29225(T) = JCM 19357(T)). PMID:25150449

Siddiqi, Muhammad Zubair; Kim, Yeon-Ju; Hoang, Van-An; Siddiqi, Muhammad Hanif; Huq, Md Amdadul; Yang, Deok-Chun

2014-12-01

76

Improved protocol for isolation of Campylobacter spp. from retail broiler meat and use of pulsed field gel electrophoresis for the typing of isolates.  

PubMed

To improve the detection of Campylobacter spp. in retail broiler meat, a reference method (R subsamples) based on the enrichment of 25 g of meat in Bolton broth at 42°C under microaerobiosis was compared with an alternative method (A subsamples) consisting in the rinsing of meat samples for 30s in buffered peptone water with antimicrobials with incubation at 42°C under aerobiosis. One piece of meat (breasts, tenderloins and thighs) was rinse in experiment 1 (A1) and two pieces in experiment 2 (A2). Campylobacter spp. were isolated on agar plates and identified by PCR. Retail samples in Alabama had less prevalence (P ? 0.05) than samples in the state of Washington. The percentage of positive was higher (P ? 0.05) in A than in R subsamples and rinsing two pieces of meat yielded the highest percentage of positive subsamples. R subsamples showed variations in the prevalence by product. However, A subsamples had similar prevalence of positives among products compare to the result from reference method. More Campylobacter coli isolates were collected in A2 subsamples. Pulse field gel electrophoresis (PFGE) was used as subtyping method to study the genome similarity among the isolates from all methods. A larger diversity of isolates were detected by PFGE in A2 subsamples. Denaturing gradient gel electrophoresis analysis suggested that the initial bacterial populations of the meat samples impact the final bacterial profile after enrichment. Rinsing broiler meats was less time consuming, required less sample preparation and was more sensitive than the reference method for the isolation of naturally occurring Campylobacter spp. This new method could help with epidemiological and intervention studies to control Campylobacter spp. PMID:23545445

Oyarzabal, Omar A; Williams, Aretha; Zhou, Ping; Samadpour, Mansour

2013-10-01

77

Pedobacter seoulensis sp. nov., isolated from soil of a bamboo field.  

PubMed

A Gram-stain negative, strictly aerobic, motile by gliding, rod-shaped and yellow pigmented strain THG-G12T was isolated from soil of a bamboo field in Seoul, Republic of Korea. Strain THG-G12T was observed to grow well at 20–28 °C and pH 7.0–7.5 in the absence of NaCl on nutrient agar. Based on 16S rRNA gene sequence comparisons, strain THG-G12T was found to be most closely related to Pedobacter ginsengisoli Gsoil 104T (97.5 % sequence similarity), Pedobacter steynii WB2.3-45T (97.4 %), Pedobacter metabolipauper WB2.3-71T (97.2 %), Pedobacter nyackensis NWG-II14T (97.2 %), Pedobacter caeni LMG 22862T (97.1 %) and Pedobacter duraquae WB2.1-25T (97.0 %), but DNA relatedness between strain THG-G12T and its phylogenetically closest neighbours was below 9.5 %. The G+C content of the genomic DNA was determined to be 39.9 mol%. The only isoprenoid quinone detected in strain THG-G12T was menaquinone-7 (MK-7). The major component in the polyamine pattern was sym-homospermidine. The major polar lipids were found to be phosphatidylethanolamine, unidentified phosphoglycolipids, unidentified aminophosphoglycolipids, unidentified aminolipids and unidentified lipids. Strain THG-G12T showed the presence of two ceramide phosphorylethanolamines (CerPE-2? and CerPE-2?), dihydrosphingosines and an unidentified ceramide as the major ceramide. The major fatty acids were identified as summed feature 3 (as defined by the MIDI system; C16:1 ?7c and/or C16:1 ?6c) and iso-C15:0. These data support the affiliation of strain THG-G12T to the genus Pedobacter. The results of physiological and biochemical tests enabled strain THG-G12T to be differentiated genotypically and phenotypically from the recognized species of the genus Pedobacter. Therefore, the novel isolate represents a novel species, for which the name Pedobacter seoulensis sp. nov. is proposed, with THG-G12T as the type strain (=KACC 17529T =JCM 19363T). PMID:24659428

Ngo, Hien T T; Son, Heung-Min; Park, Sang-Yong; Kim, Ki-Young; Yi, Tae-Hoo

2014-05-01

78

Genomic relatedness among Actinobacillus pleuropneumoniae field strains of sterotypes 1 and 5 isolated from healthy and diseased pigs.  

PubMed Central

Forty-four Actinobacillus pleuropneumoniae isolates recovered from both healthy and diseased pigs were characterized by random amplified polymorphic DNA analysis (RAPD), pulsed field gel electrophoresis (PFGE) and apx toxin gene typing. Nine RAPD types and 14 PFGE patterns were identified. No common RAPD or PFGE patterns were found between strains of serotype 1 and those of serotype 5. The RAPD analysis indicated that the 15 serotype 1 strains isolated from diseased pigs were assigned to 4 RAPD types, with 66% of strains characterized by the same RAPD type. By contrast, the 5 strains of serotype 1 isolated from healthy carriers were dispersed in 4 RAPD types. These data suggest that the diversity of strains isolated from healthy pigs could be higher than that of strains recovered from diseased pigs. In addition, all serotype 5 strains exhibited a unique RAPD type. Unlike RAPD, PFGE analysis allowed discrimination among isolates of serotype 1 and among those of serotype 5. All but 3 isolates showed the same apx genotype as their respective serotype reference strain. These data indicate that RAPD analysis is a valuable rapid tool for routine subtyping of strains of serotype 1. For strains of serotype 5, a combination of several typing methods, such as PFGE and apx gene typing, is needed to provide useful information on the molecular epidemiology of swine pleuropneumonia. Images Figure 1. Figure 3. PMID:10480458

Chatellier, S; Harel, J; Dugourd, D; Chevallier, B; Kobisch, M; Gottschalk, M

1999-01-01

79

Resistance to anticoccidial drugs of Dutch avian Eimeria spp. field isolates originating from 1996, 1999 and 2001.  

PubMed

Fifteen Eimeria spp. field isolates sampled on Dutch broiler farms were subjected to an Anticoccidial Sensitivity Test (AST) in a battery cage study. Four isolates dated from 1996, another four from 1999 and the last seven isolates from 2001. The selected anticoccidial drugs were monensin, narasin, salinomycin, lasalocid, nicarbazin, diclazuril, halofuginone, maduramicin and meticlorpindol/methylbenzoquate. Maduramicin and halofuginone were not included in the ASTs of 1999 and 2001, while meticlorpindol/methylbenzoquate was not tested in 1996 and 1999. Eimeria acervulina present in each of the four 1996 field isolates showed resistance for almost all products tested except maduramicin (1/4) and salinomycin (114), which appeared to be reduced sensitive. In 1999 the same species presented a similar resistance pattern for most products, although reduced sensitivity occurred for salinomycin (1/4), and sensitivity was found for diclazuril (2/4), monensin (1/4) and narasin (1/4). In the year 2001 increased sensitivity to various products was found. Higher sensitivity was found for meticlorpindol/ methylbenzoquate (7/7) and salinomycin and narasin (both 4/7), followed by nicarbazin (3/7) and monensin (2/7). Reduced sensitivity was found for monensin (3/7), lasalocid (2/7), salinomycin and narasin (1/7). E. maxima was only found in one field isolate per year. The E. maxima from 1996 was resistant to all products except narasin (sensitive) and halofuginone (reduced sensitive). In 1999 this species was reduced sensitive to narasin and lasalocid, showing resistance for the other products. The strain originating from the 2001 isolate was reduced sensitive to most products except monensin and narasin (resistant). Full sensitivity was found for meticlorpindol/ methylbenzoquate. E. tenella was present in one isolate of 1996, two of 1999 and four isolates of 2001. The AST of 1996 showed reduced sensitivity for nicarbazin, and sensitive to narasin, maduramicin and halofuginone. All other products showed resistance. In 1999 both strains showed resistance to all products tested. For the year 2001 full sensitivity was found to meticlorpindol/methylbenzoquate. Sensitivity was also found for salinomycin (1/4), nicarbazin (2/4), diclazuril (2/4) and lasalocid (2/4), monensin (1/4) and narasin (1/4). Reduced sensitivity was found for nicarbazin (1/4), lasalocid (1/4) and narasin (1/4). The different resistance patterns of Dutch coccidiosis isolates and resistance of coccidia in general is discussed. PMID:17585463

Peek, H W; Landman, W J M

2003-08-01

80

Heterogeneity of molecular resistance patterns in antimony-resistant field isolates of Leishmania species from the western Mediterranean area.  

PubMed

Antimonials remain the first-line treatment for the various manifestations of leishmaniasis in most areas where the disease is endemic, and increasing cases of therapeutic failure associated with parasite resistance have been reported. In this study, we assessed the molecular status of 47 clinical isolates of Leishmania causing visceral and cutaneous leishmaniasis from Algeria, Tunisia, and southern France. In total, we examined 14 genes that have been shown to exhibit significant variations in DNA amplification, mRNA levels, or protein expression with respect to resistance to antimonials. The gene status of each clinical isolate was assessed via qPCR and qRT-PCR. We then compared the molecular pattern against the phenotype determined via an in vitro sensitivity test of the clinical isolates against meglumine antimoniate, which is considered the reference technique. Our results demonstrate significant DNA amplification and/or RNA overexpression in 56% of the clinical isolates with the resistant phenotype. All clinical isolates that exhibited significant overexpression of at least 2 genes displayed a resistant phenotype. Among the 14 genes investigated, 10 genes displayed either significant amplification or overexpression in at least 1 clinical isolate; these genes are involved in several metabolic pathways. Moreover, various gene associations were observed depending on the clinical isolates, supporting the multifactorial nature of Leishmania resistance. Molecular resistance features were found in the 3 Leishmania species investigated (Leishmania infantum, Leishmania major, and Leishmania killicki). To our knowledge, this is the first report of the involvement of molecular resistance genes in field isolates of Leishmania major and Leishmania killicki with the resistance phenotype. PMID:24913173

Jeddi, Fakhri; Mary, Charles; Aoun, Karim; Harrat, Zoubir; Bouratbine, Aïda; Faraut, Françoise; Benikhlef, Rezika; Pomares, Christelle; Pratlong, Francine; Marty, Pierre; Piarroux, Renaud

2014-08-01

81

[Typing of Shigella sonnei strains isolated in some provinces of Turkey using antimicrobial resistance and pulsed field gel electrophoresis methods].  

PubMed

Shigella species may lead to large epidemics owing to their low infective doses and frequent transmission from person to person with high secondary attack rates. Shigella sonnei is one of the most prevalent causative agent of infectious gastroenteritis in developing and developed countries and it is the most frequently reported Shigella serotype from Turkey in recent years. The aim of this study was to determine the types of S. sonnei strains isolated in different provinces of Turkey [in Marmara earthquake regions (Izmit, n=5; Adapazari, n=6; Yalova, n=2) in 1999 and in Ankara (n=17) in 1997, 2000 and 2001] according to their antimicrobial resistance and pulsed field gel electrophoresis (PFGE) patterns. All isolates were found sensitive to gentamicin, ceftriaxone, imipenem, nalidixic acid and ciprofloxacin. Twenty three (76.6%) of isolates were found resistant to streptomycin, 21 (70%) to trimethoprim-sulfamethoxazole, 20 (66.6%) to tetracycline, 6 (20%) to ampicillin, 3 (10%) to ampicillin/sulbactam and 1 (3.3%) to chloramphenicol. Three (%10) isolates were detected as intermediate susceptible to tetracycline and cefoperazone, while four isolates (13.3%) were susceptible to all antimicrobial agents tested. A total of nine different patterns were obtained according to antimicrobial resistance patterns. PFGE was performed by Xbal restriction enzyme. Isolates were grouped into A (n=24) and B (n=6) main PFGE types and into 13 closely or possibly related types. A total of 15 different PFGE patterns were identified among the isolates. It was determined that isolates from the same clone disseminated in Ankara during the years 2000-2001. Overall, different clones of S. sonnei strains were in dissemination in the provinces included. This study indicated that different S. sonnei clones were in circulation in Turkey and these results constitute the basic molecular preliminary data for the National Enteric Pathogens Laboratory Network in Turkey. PMID:19149077

Akçali, Alper; Levent, Belkis; Akba?, Efsun; Esen, Berrin

2008-10-01

82

Dyella ginsengisoli sp. nov., isolated from soil of a ginseng field in South Korea.  

PubMed

A Gram-negative, aerobic, yellow-pigmented, non-spore-forming, motile, rod-shaped bacterium, designated strain Gsoil 3046(T), was isolated from soil from a ginseng field in Pocheon Province, South Korea, and was characterized taxonomically by using a polyphasic approach. A comparative analysis of 16S rRNA gene sequences revealed that strain Gsoil 3046(T) belongs to the family Xanthomonadaceae in the Gammaproteobacteria. The greatest sequence similarity was found with respect to Dyella koreensis KCTC 12359(T) (97.7 %), Dyella japonica IAM 15069(T) (97.4 %), Frateuria aurantia DSM 6220(T) (96.7 %), Fulvimonas soli LMG 19981(T) (96.2 %) and Luteibacter rhizovicinus DSM 16549(T) (96.0 %). The phylogenetic distances from other recognized species within the family Xanthomonadaceae, including Dyella yeojuensis KACC 11405(T), were greater than 4.0 % (i.e. the sequence similarities were less than 96.0 %). DNA-DNA hybridization experiments showed that the levels of DNA-DNA relatedness between strain Gsoil 3046(T) and its phylogenetically closest neighbours were below 25 %. The G+C content of the genomic DNA was 66.6 mol%. In addition, the presence of ubiquinone Q-8 as the predominant respiratory quinone, iso-C(17 : 1)omega9c, iso-C(16 : 0), iso-C(15 : 0) and iso-C(17 : 0) as the major cellular fatty acids and iso-C(13 : 0) 3-OH and iso-C(11 : 0) 3-OH as the major hydroxy fatty acids supported the affiliation of strain Gsoil 3046(T) to the genus Dyella. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 3046(T) represents a novel species in the genus Dyella, for which the name Dyella ginsengisoli sp. nov. is proposed. The type strain is Gsoil 3046(T) (=KCTC 12599(T)=DSM 18387(T)). PMID:19244422

Jung, Hae-Min; Ten, Leonid N; Kim, Kyoung-Ho; An, Dong Shan; Im, Wan-Taek; Lee, Sung-Taik

2009-03-01

83

Pusillimonas ginsengisoli sp. nov., isolated from soil of a ginseng field.  

PubMed

Two novel strains of Gram-negative, non-sporulating, short rod-shaped, motile bacteria, designated DCY25T and DCY28, were isolated from soil of a ginseng field in South Korea and characterized in order to determine their taxonomic position. 16S rRNA gene sequence analysis showed that strains DCY25T and DCY28 belonged to the Betaproteobacteria, the highest sequence similarities being found with Pusillimonas noertemannii BN9T (96.9%), Bordetella trematum DSM 11334(T) (95.9%), Achromobacter denitrificans DSM 30026T (95.9%), Achromobacter insolitus LMG 6003T (95.8%) and Pigmentiphaga kullae K24T (95.5%). Chemotaxonomic data revealed that both strains DCY25T and DCY28 possessed ubiquinone Q-8. Fatty acid analysis of strain DCY25T demonstrated the presence of 19:0 cyclo omega8c (22.8%) and 16:0 (16.6%). The polar lipid profiles of strains DCY25T and DCY28 included phosphatidylethanolamine, phosphatidylglycerol, two unknown aminolipids and diphosphatidylglycerol. The G+C contents of strains DCY25T and DCY28 were 57.3 and 57.2 mol%, respectively. DNA-DNA relatedness values, biochemical and physiological characteristics strongly supported the genotypic and phenotypic differentiation of strains DCY25T and DCY28 from Pusillimonas noertemannii. Therefore, strains DCY25T and DCY28 should be classified in a novel species, for which the name Pusillimonas ginsengisoli sp. nov. is proposed. The type strain is DCY25T (=KCTC 22046T =JCM 14767T); strain DCY28 (=KCTC 22047=JCM 14768) is a reference strain. PMID:19749028

Srinivasan, Sathiyaraj; Kim, Myung Kyum; Sathiyaraj, Gayathri; Kim, Yeon-Ju; Yang, Deok-Chun

2010-08-01

84

Use of the Chrome Azurol S Agar Plate Technique To Differentiate Strains and Field Isolates of Rhizobium leguminosarum biovar trifolii.  

PubMed

Identification of Rhizobium and Bradyrhizobium strains and especially of indigenous isolates continues to be one of the major difficulties associated with competition studies. Because there is no universally accepted method, the method of choice depends on preference, experience, and equipment. Here, an agar plate technique was used to distinguish strains and field isolates of Rhizobium leguminosarum biovar trifolii to provide a basis for identifying nodule occupants in further competition studies. A rapid plate technique, based on differential growth characteristics, complements other techniques such as serological reactions, particularly when antisera cross-react with nonhomologous strains. The technique involves culturing strains and isolates on chrome azurol S agar. Although similar responses were observed among some strains, the response was highly reproducible and was considered an ideal complementary technique used in conjunction with serological procedures. Strains with similar responses could often be differentiated by varying media components, such as the source of carbon. PMID:16347877

Ames-Gottfred, N P; Christie, B R; Jordan, D C

1989-03-01

85

Symbiotic Characteristics of Rhizobium leguminosarum bv. trifolii Isolates Which Represent Major and Minor Nodule-Occupying Chromosomal Types of Field-Grown Subclover (Trifolium subterraneum L.) †  

PubMed Central

The symbiotic effectiveness and nodulation competitiveness of Rhizobium leguminosarum bv. trifolii soil isolates were evaluated under nonsoil greenhouse conditions. The isolates which we used represented both major and minor nodule-occupying chromosomal types (electrophoretic types [ETs]) recovered from field-grown subclover (Trifolium subterraneum L.). Isolates representing four ETs (ETs 2, 3, 7, and 8) that were highly successful field nodule occupants fixed between 2- and 10-fold less nitrogen and produced lower herbage dry weights and first-harvest herbage protein concentrations than isolates that were minor nodule occupants of field-grown plants. Despite their equivalent levels of abundance in nodules on field-grown subclover plants, ET 2 and 3 isolates exhibited different competitive nodulation potentials under nonsoil greenhouse conditions. ET 3 isolates generally occupied more subclover nodules than isolates belonging to other ETs when the isolates were mixed in 1:1 inoculant ratios and inoculated onto seedlings. In contrast, ET 2 isolates were less successful at nodulating under these conditions. In many cases, ET 2 isolates required a numerical advantage of at least 6:1 to 11:1 to occupy significantly more nodules than their competitors. We identified highly effective isolates that were as competitive as the ET 3 isolates despite representing serotypes that were rarely recovered from nodules of field-grown plants. When one of the suboptimally effective isolates (ET2-1) competed with an effective and competitive isolate (ET31-5) at several different inoculant ratios, the percentages of nodules occupied by the former increased as its numerical advantage increased. Although subclover yields declined as nodule occupancy by ET2-1 increased, surprisingly, this occurred at inoculant ratios at which large percentages of nodules were still occupied by ET31-5. PMID:16349172

Leung, K.; Wanjage, F. N.; Bottomley, P. J.

1994-01-01

86

Quantitative Field Testing Rotylenchulus reniformis DNA from Metagenomic Samples Isolated Directly from Soil  

PubMed Central

A quantitative PCR procedure targeting the ?-tubulin gene determined the number of Rotylenchulus reniformis Linford & Oliveira 1940 in metagenomic DNA samples isolated from soil. Of note, this outcome was in the presence of other soil-dwelling plant parasitic nematodes including its sister genus Helicotylenchus Steiner, 1945. The methodology provides a framework for molecular diagnostics of nematodes from metagenomic DNA isolated directly from soil. PMID:22194958

Showmaker, Kurt; Lawrence, Gary W.; Lu, Shien; Balbalian, Clarissa; Klink, Vincent P.

2011-01-01

87

Isolation of Buggy Creek Virus (Togaviridae: Alphavirus) From Field-Collected Eggs of Oeciacus vicarius (Hemiptera: Cimicidae)  

PubMed Central

Alphaviruses (Togaviridae) rarely have been found to be vertically transmitted from female arthropods to their progeny. We report two isolations of Buggy Creek virus (BCRV), an ecologically unusual alphavirus related to western equine encephalomyelitis virus, from field-collected eggs of cimicid swallow bugs (Oeciacus vicarius Horvath), the principal vector for BCRV. Ten percent of egg pools were positive for BCRV, and we estimated minimum infection rates to be 1.03 infected eggs per 1,000 tested. The results show potential vertical transmission of BCRV, represent one of the few isolations of any alphavirus from eggs or larvae of insects in the field, and are the first report of any virus in the eggs of cimicid bedbugs. The specialized ecological niche of BCRV in swallow bugs and at cliff swallow (Petrochelidon pyrrhonota Vieillot) nesting sites may promote vertical transmission of this virus. PMID:19351091

Brown, Charles R.; Moore, Amy T.; Young, Ginger R.; Padhi, Abinash; Komar, Nicholas

2009-01-01

88

Isolation of Buggy Creek virus (Togaviridae: Alphavirus) from field-collected eggs of Oeciacus vicarius (Hemiptera: Cimicidae).  

PubMed

Alphaviruses (Togaviridae) rarely have been found to be vertically transmitted from female arthropods to their progeny. We report two isolations of Buggy Creek virus (BCRV), an ecologically unusual alphavirus related to western equine encephalomyelitis virus, from field-collected eggs of cimicid swallow bugs (Oeciacus vicarius Horvath), the principal vector for BCRV. Ten percent of egg pools were positive for BCRV, and we estimated minimum infection rates to be 1.03 infected eggs per 1,000 tested. The results show potential vertical transmission of BCRV, represent one of the few isolations of any alphavirus from eggs or larvae of insects in the field, and are the first report of any virus in the eggs of cimicid bedbugs. The specialized ecological niche of BCRV in swallow bugs and at cliff swallow (Petrochelidon pyrrhonota Vieillot) nesting sites may promote vertical transmission of this virus. PMID:19351091

Brown, Charles R; Moore, Amy T; Young, Ginger R; Padhi, Abinash; Komar, Nicholas

2009-03-01

89

Some properties of pea enation mosaic virus isolated from field pea and broad bean plants in Bohemia  

Microsoft Academic Search

Pea enation mosaic virus (PEMV) was isolated from disea sed field pea (Pisum sativum L.ssp. arvense A.Gr.) and broad bean (Faba vulgaris Moench) plants grown as filed crops at Bohumilice in Bohemia. The virus proved to be pathogenic for the following plant species:Pisum sativum L. cv. Raman,Faba vulgaris Moench,Lens culinaris Med.,Vicia sativa L.,Lathyrus odoratus L.,Glycine soja L.,Phaseolus vulgaris L.,Chenopodium amaranticolor

M. Musil; Olga Lešková

1969-01-01

90

Dyella kyungheensis sp. nov., isolated from soil of a cornus fruit field.  

PubMed

A Gram-reaction-negative, aerobic, motile by one polar flagellum, yellow-pigmented, rod-shaped bacterium, designated strain THG-B117(T), was isolated from soil of a cornus fruit field of Hoengseong province in South Korea and its taxonomic position was investigated by a polyphasic study. Strain THG-B117(T) grew well at 25-30 °C and at pH 6.0-8.0 in the absence of NaCl on nutrient agar. On the basis of 16S rRNA gene sequence similarity, strain THG-B117(T) was shown to belong to the family Xanthomonadaceae and be related to Dyella japonica XD53(T) (98.7?% similarity), Dyella terrae JS14-6(T) (98.0?%), Dyella koreensis BB4(T) (96.9?%), Dyella soli JS12-10(T) (96.9?%) and Dyella thiooxydans ATSB10(T) (96.7?%). DNA-DNA hybridization experiments showed that DNA relatedness between strain THG-B117(T) and its phylogenetically closest neighbours was below 45.1?%. The G+C content of the genomic DNA of strain THG-B117(T) was 64.8 mol%. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, unidentified aminolipids, unidentified aminophospholipids and unidentified phospholipids. Phenotypic and chemotaxonomic data (major ubiquinone was Q-8, and major fatty acids were iso-C15?:?0, iso-C16?:?0, iso-C17?:?0 and iso-C17?:?1?9c) supported the affiliation of strain THG-B117(T) with the genus Dyella. The results of physiological and biochemical tests suggested that strain THG-B117(T) was different genotypically and phenotypically from recognized species of the genus Dyella, and represents a novel species of this genus. The name Dyella kyungheensis sp. nov. is proposed, with the type strain THG-B117(T) (?=?KACC 16981(T)?=?JCM 18747(T)). PMID:23667147

Son, Heung-Min; Yang, Jung-Eun; Yi, Eun-Ji; Park, YongJin; Won, Kyung-Hwa; Kim, Ju-Han; Han, Chang-Kyun; Kook, MooChang; Yi, Tae-Hoo

2013-10-01

91

Flavobacterium aquaticum sp. nov., isolated from a water sample of a rice field.  

PubMed

Strain JC164(T) was isolated from a water sample from a rice field at Jamdih, Mau, Uttar Pradesh, India. Colonies of strain JC164(T) were brown-yellow and cells were Gram-stain-negative. Catalase, oxidase and amylase were present. iso-C(15:0), iso-C(16:0), iso-C15?1 G, iso-C(15:0) 3-OH and iso-C(14:0) were the predominant fatty acids with minor amounts of iso-C(16:0) 3-OH, anteiso-C(15:0), C(16:0), iso-C(16:1) H, iso-C(14:0) 3-OH and iso-C(13:0). Strain JC164(T) contained phosphatidylethanolamine and a few unidentified lipids (L1, L3 and L6) as major polar lipids. Bacteriohopane derivative 1 (BHD1) and diplopterol (DPL) were the major hopanoids. ?-Carotene was one among the several spirilloxanthin series carotenoids present in strain JC164(T). Genomic DNA G+C content was 39.6 mol%. 16S rRNA gene sequence comparisons indicated that strain JC164(T) represents a member of the genus Flavobacterium (family Flavobacteriaceae, class Flavobacteriia). The most closely related taxa to strain JC164(T) were Flavobacterium sasangense YC6274(T) (98.5%), Flavobacterium cucumis R2A45-3(T) (98.1%), Flavobacterium cheniae NJ-26(T) (97.2%) and the novel strain possessed <95.1% sequence similarity with other members of the genus Flavobacterium. However, strain JC164(T) showed 12.5 ± 2, 13.6 ± 1 and 17.4 ± 2% genomic DNA association (based on DNA-DNA hybridization) with Flavobacterium sasangense KCTC 22246(T), Flavobacterium cucumis DSM 18830(T) and Flavobacterium cheniae CGMCC 1.6844(T), respectively. The distinct genomic difference and morphological, physiological and chemotaxonomic differences from the previously described taxa support the classification of strain JC164(T) as a representative of a novel species of the genus Flavobacterium, for which the name Flavobacterium aquaticum sp. nov. is proposed. The type strain is JC164(T) (?=?KCTC 32196(T)?=?CGMCC 1.12398=LMG 27251(T)). PMID:23543500

Subhash, Y; Sasikala, Ch; Ramana, Ch V

2013-09-01

92

Aquaporin 2 Mutations in Trypanosoma brucei gambiense Field Isolates Correlate with Decreased Susceptibility to Pentamidine and Melarsoprol  

PubMed Central

The predominant mechanism of drug resistance in African trypanosomes is decreased drug uptake due to loss-of-function mutations in the genes for the transporters that mediate drug import. The role of transporters as determinants of drug susceptibility is well documented from laboratory-selected Trypanosoma brucei mutants. But clinical isolates, especially of T. b. gambiense, are less amenable to experimental investigation since they do not readily grow in culture without prior adaptation. Here we analyze a selected panel of 16 T. brucei ssp. field isolates that (i) have been adapted to axenic in vitro cultivation and (ii) mostly stem from treatment-refractory cases. For each isolate, we quantify the sensitivity to melarsoprol, pentamidine, and diminazene, and sequence the genomic loci of the transporter genes TbAT1 and TbAQP2. The former encodes the well-characterized aminopurine permease P2 which transports several trypanocides including melarsoprol, pentamidine, and diminazene. We find that diminazene-resistant field isolates of T. b. brucei and T. b. rhodesiense carry the same set of point mutations in TbAT1 that was previously described from lab mutants. Aquaglyceroporin 2 has only recently been identified as a second transporter involved in melarsoprol/pentamidine cross-resistance. Here we describe two different kinds of TbAQP2 mutations found in T. b. gambiense field isolates: simple loss of TbAQP2, or loss of wild-type TbAQP2 allele combined with the formation of a novel type of TbAQP2/3 chimera. The identified mutant T. b. gambiense are 40- to 50-fold less sensitive to pentamidine and 3- to 5-times less sensitive to melarsoprol than the reference isolates. We thus demonstrate for the first time that rearrangements of the TbAQP2/TbAQP3 locus accompanied by TbAQP2 gene loss also occur in the field, and that the T. b. gambiense carrying such mutations correlate with a significantly reduced susceptibility to pentamidine and melarsoprol. PMID:24130910

Graf, Fabrice E.; Ludin, Philipp; Wenzler, Tanja; Kaiser, Marcel; Brun, Reto; Pyana, Patient Pati; Buscher, Philippe; de Koning, Harry P.; Horn, David; Maser, Pascal

2013-01-01

93

Evaluation of an in vitro assay system for drug susceptibility of field isolates of Plasmodium falciparum from southern Thailand.  

PubMed

An in vitro assay system has been developed to evaluate the susceptibility of field isolates of Plasmodium falciparum to standard and new antimalarials. The assay used drugs which were serially diluted in the field and determined effective drug concentrations by quantitating schizont maturation after a variable incubation period. Based on the ID50 values, a series of isolates from Yala in southern Thailand were shown to be resistant to chloroquine (187 nM) but only moderately resistant to amodiaquine (23.7 nM), a structurally related 4-aminoquinoline. Five aminocarbinols were evaluated. The parasites were resistant to quinine (219 nM), but comparatively much more susceptible to mefloquine (9.04 nM), halofantrine (1.23 nM), and enpiroline (6.23 nM). The isolates were also relatively sensitive to WR 194,965 (9.04 nM). Two dihydrofolate reductase inhibitors (WR 99,210 and pyrimethamine) were tested. The isolates were comparatively sensitive to a dihydrotriazine, WR 99,210 (2.85 nM). The in vitro values for pyrimethamine (1,870 nM) were higher than the values for the other drugs tested, but were less than values from other regions of Thailand. As compared to a survey conducted in this region four years previously, values for chloroquine, pyrimethamine, amodiaquine, and mefloquine have remained relatively unchanged. However, there was a greater than 20-fold rise in the susceptibility values for quinine, suggesting the introduction of quinine-resistant isolates from eastern Thailand into southern Thailand during this period. PMID:3277459

Childs, G E; Wimonwattrawatee, T; Pooyindee, N

1988-01-01

94

Effective Preparation of Plasmodium vivax Field Isolates for High-Throughput Whole Genome Sequencing  

PubMed Central

Whole genome sequencing (WGS) of Plasmodium vivax is problematic due to the reliance on clinical isolates which are generally low in parasitaemia and sample volume. Furthermore, clinical isolates contain a significant contaminating background of host DNA which confounds efforts to map short read sequence of the target P. vivax DNA. Here, we discuss a methodology to significantly improve the success of P. vivax WGS on natural (non-adapted) patient isolates. Using 37 patient isolates from Indonesia, Thailand, and travellers, we assessed the application of CF11-based white blood cell filtration alone and in combination with short term ex vivo schizont maturation. Although CF11 filtration reduced human DNA contamination in 8 Indonesian isolates tested, additional short-term culture increased the P. vivax DNA yield from a median of 0.15 to 6.2 ng µl?1 packed red blood cells (pRBCs) (p?=?0.001) and reduced the human DNA percentage from a median of 33.9% to 6.22% (p?=?0.008). Furthermore, post-CF11 and culture samples from Thailand gave a median P. vivax DNA yield of 2.34 ng µl?1 pRBCs, and 2.65% human DNA. In 22 P. vivax patient isolates prepared with the 2-step method, we demonstrate high depth (median 654X coverage) and breadth (?89%) of coverage on the Illumina GAII and HiSeq platforms. In contrast to the A+T-rich P. falciparum genome, negligible bias was observed in coverage depth between coding and non-coding regions of the P. vivax genome. This uniform coverage will greatly facilitate the detection of SNPs and copy number variants across the genome, enabling unbiased exploration of the natural diversity in P. vivax populations. PMID:23308154

Auburn, Sarah; Marfurt, Jutta; Maslen, Gareth; Campino, Susana; Ruano Rubio, Valentin; Manske, Magnus; MacHunter, Barbara; Kenangalem, Enny; Noviyanti, Rintis; Trianty, Leily; Sebayang, Boni; Wirjanata, Grennady; Sriprawat, Kanlaya; Alcock, Daniel; MacInnis, Bronwyn; Miotto, Olivo; Clark, Taane G.; Russell, Bruce; Anstey, Nicholas M.; Nosten, Francois; Kwiatkowski, Dominic P.; Price, Ric N.

2013-01-01

95

Field collection and genetic classification of tick-borne Rickettsiae and Rickettsiae-like pathogens from South Texas: Coxiella burnetii isolated from field-collected Amblyomma cajennense.  

PubMed

We are reporting the first known isolation of the Q-fever agent Coxiella burnetii from field-collected cayenne ticks Amblyomma cajennense in North America. Q-fever affects a number of domestic ungulates where it can lead to abortion in sheep and goats. There is far less known about the disease's effects on wild species, primarily because of the tendency of the disease to self resolve and to provide long-term immunity to subsequent infections. The first recovery of C. burnetii in North America was from the tick species Dermacentor andersoni. Since the original isolation C. burnetii has been recovered from five other North American tick species. The currently accepted mode for the majority of human infections is inhalation. The Centers for Disease Control and Prevention, Division of Viral and Rickettsial Diseases, Rickettsial Zoonoses Branch asserts the Q-fever agent as requiring as few as one organism to cause disease via inhalation in susceptible humans. However, with more and more isolations from ticks, evidence linking C. burnetii and ticks is mounting. The true role of tick species as competent vectors is still unconfirmed. Preemptive field collections of possible vector arthropods, hosts, and reservoirs can provide invaluable baseline environmental data that will prove supportive in follow-up studies and abatement efforts. PMID:19120212

Sanders, David M; Parker, Jill E; Walker, Wes W; Buchholz, Matt W; Blount, Keith; Kiel, Johnathan L

2008-12-01

96

Genetic polymorphism of merozoite surface protein-1 and merozoite surface protein-2 in Plasmodium falciparum field isolates from Myanmar  

PubMed Central

Background Merozoite surface protein-1 (MSP-1) and MSP-2 of Plasmodium falciparum are potential vaccine candidate antigens for malaria vaccine development. However, extensive genetic polymorphism of the antigens in field isolates of P. falciparum represents a major obstacle for the development of an effective vaccine. In this study, genetic polymorphism of MSP-1 and MSP-2 among P. falciparum field isolates from Myanmar was analysed. Methods A total of 63 P. falciparum infected blood samples, which were collected from patients attending a regional hospital in Mandalay Division, Myanmar, were used in this study. The regions flanking the highly polymorphic characters, block 2 for MSP-1 and block 3 for MSP-2, were genotyped by allele-specific nested-PCR to analyse the population diversity of the parasite. Sequence analysis of the polymorphic regions of MSP-1 and MSP-2 was also conducted to identify allelic diversity in the parasite population. Results Diverse allelic polymorphism of MSP-1 and MSP-2 was identified in P. falciparum isolates from Myanmar and most of the infections were determined to be mixed infections. Sequence analysis of MSP-1 block 2 revealed that 14 different alleles for MSP-1 (5 for K1 type and 9 for MAD20 type) were identified. For MSP-2 block 3, a total of 22 alleles (7 for FC27 type and 15 for 3D7 type) were identified. Conclusion Extensive genetic polymorphism with diverse allele types was identified in MSP-1 and MSP-2 in P. falciparum field isolates from Myanmar. A high level of mixed infections was also observed, as was a high degree of multiplicity of infection. PMID:20478015

2010-01-01

97

Degradation of Phenanthrene by Bacterial Strains Isolated from Soil in Oil Refinery Fields in Korea  

Microsoft Academic Search

The degradation of phenanthrene, a model PAH compound, by microorganisms either in the mixed culture or individual strain, isolated from oil-contaminated soil in oil refinery vicinity sites, was examined. The effects of pH, temperature, initial concentration of phenanthrene, and the addition of carbon sources on biodegradation potential were also investigated. Results showed that soil samples collected from four oil refinery

JEONG-DONG KIM; SU-HYEUN SHIM; CHOUL-GYUN LEE

2005-01-01

98

POPULATION SYNTHESIS OF YOUNG ISOLATED NEUTRON STARS: THE EFFECT OF FALLBACK DISK ACCRETION AND MAGNETIC FIELD EVOLUTION  

SciTech Connect

The spin evolution of isolated neutron stars (NSs) is dominated by their magnetic fields. The measured braking indices of young NSs show that the spin-down mechanism due to magnetic dipole radiation with constant magnetic fields is inadequate. Assuming that the NS magnetic field is buried by supernova fallback matter and re-emerges after accretion stops, we carry out a Monte Carlo simulation of the evolution of young NSs, and show that most of the pulsars have braking indices ranging from –1 to 3. The results are compatible with the observational data of NSs associated with supernova remnants. They also suggest that the initial spin periods of NSs might occupy a relatively wide range.

Fu, Lei; Li, Xiang-Dong, E-mail: lixd@nju.edu.cn [Department of Astronomy, Nanjing University, Nanjing 210093 (China)

2013-10-01

99

New isolated gate bipolar transistor two-quadrant chopper power supply for a fast field cycling nuclear magnetic resonance spectrometer  

NASA Astrophysics Data System (ADS)

This work, presents, for the first time, an Isolated Gate Bipolar Transistor (IGBT) two-quadrant chopper power supply for a fast field cycling (FFC) nuclear magnetic resonance spectrometer. This power supply was designed to achieve a maximum current of 200 A with good efficiency, low semiconductor losses, low cost, and easy maintenance. Both energy storage circuits and dumping circuits are used to obtain switching times less than 2 ms between field levels in agreement with the FFC technique specifications. The current ripple at high currents is better than 1×10-4 and presents a specific shape which can be used for additional compensation using auxiliary circuits. The implemented power supply was tested and been continuously operating with a home-built FFC solenoidal magnet, associated cooling system, and rf units for fields between 0 and 0.2 T.

Sousa, D. M.; Marques, G. D.; Sebastião, P. J.; Ribeiro, A. C.

2003-10-01

100

Efficacy of commercial canarypox vaccine for protecting Hawai'i 'Amakihi from field isolates of Avipoxvirus  

USGS Publications Warehouse

At least three variants of avian pox virus are present in Hawai‘i - Fowlpox from domestic poultry and a group of genetically distinct viruses that cluster within two clades (Pox Variant 1 and Pox Variant 2) that are most similar to Canarypox based on DNA sequence of the virus 4b core protein gene. We tested whether Hawai‘i ‘Amakihi can be protected from wild virus isolates with an attenuated live Canarypox vaccine that is closely related to isolates that cluster within clade 1 (Pox Variant 1) based on sequence of the attenuated Canarypox virus 4b core protein. Thirty-one (31) Hawai`i ‘Amakihi (Hemignathus virens) with no prior physical evidence of pox infection were collected on Mauna Kea from xeric, high elevation habitats with low pox prevalence and randomly divided into two groups. One group of 16 was vaccinated with Poximmune C® while the other group received a sham vaccination with virus diluent. Four of 15 (27%) vaccinated birds developed potentially life-threatening disseminated lesions or lesions of unusually long duration, while one bird never developed a vaccine-associated lesion or "take". After vaccine-associated lesions healed, vaccinated birds were randomly divided into three groups of five and challenged with either a wild isolate of Fowlpox, a Hawai`i `Amakihi isolate of a Canarypox-like virus from clade 1 (Pox Variant 1) or a Hawai`i `Amakihi isolate of a Canarypox-like virus from clade 2 (Pox Variant 2). Similarly, three random groups of five unvaccinated ‘Amakihi were challenged with the same virus isolates. Vaccinated and unvaccinated ‘Amakihi challenged with Fowlpox had transient infections with no clinical signs of infection. Mortality in vaccinated ‘Amakihi that were challenged with Pox Variant 1 and Pox Variant 2 ranged from 0% (0/5) for Pox Variant 1 to 60% (3/5) for Pox Variant 2. Mortality in unvaccinated ‘Amakihi ranged from 40% (2/5) for Pox Variant 1 to 100% (5/5) for Pox Variant 2. While the vaccine provided some protection against Pox Variant 1, serious side effects and low efficacy against Pox Variant 2 make it risky to use in captive or wild honeycreepers.

Atkinson, Carter T.; Wiegand, Kimberly C.; Triglia, Dennis; Jarvi, Susan I.

2010-01-01

101

Genetic Analysis of Fenhexamid-Resistant Field Isolates of the Phytopathogenic Fungus Botrytis cinerea? †  

PubMed Central

The hydroxyanilide fenhexamid, one of the latest antibotrytis fungicides, active especially against leotiomycete plant-pathogenic fungi, inhibits 3-ketoreductase of the C-4-demethylation enzyme complex during ergosterol biosynthesis. We isolated Botrytis cinerea strains resistant to various levels of fenhexamid from French and German vineyards. The sequence of the gene encoding 3-ketoreductase, erg27, varied according to levels of resistance. Highly resistant isolates, termed HydR3+, all presented a modification of the phenylalanine at the C terminus of the putative transmembrane domain at position 412, either to serine (85% of the isolates), to isoleucine (11.5% of the isolates), or to valine (3.5% of the isolates). The introduction of the \\documentclass[10pt]{article} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{pmc} \\usepackage[Euler]{upgreek} \\pagestyle{empty} \\oddsidemargin -1.0in \\begin{document} \\begin{equation*}erg27^{HydR3^{+}}\\end{equation*}\\end{document} allele into a fenhexamid-sensitive strain by means of a replicative plasmid conferred fenhexamid resistance on the resulting transformants, showing that the mutations at position 412 are responsible for fenhexamid resistance. Weakly to moderately resistant isolates, termed HydR3?, showed different point mutations between the strains in the sequenced regions of the erg27 gene, corresponding to amino acid changes between positions 195 and 400 of the protein. The \\documentclass[10pt]{article} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{pmc} \\usepackage[Euler]{upgreek} \\pagestyle{empty} \\oddsidemargin -1.0in \\begin{document} \\begin{equation*}erg27^{HydR3^{-}}\\end{equation*}\\end{document} alleles on the replicative vector introduced into a sensitive strain did not confer resistance to fenhexamid. Genetic crosses between HydR3? and sensitive strains showed strict correlation between the sequenced mutation in the erg27 gene and the resistance phenotypes, suggesting that these mutations are linked to fenhexamid resistance. The HydR3 mutations possibly modify the affinity of the 3-ketoreductase enzyme for its specific inhibitor, fenhexamid. PMID:18779358

Fillinger, Sabine; Leroux, Pierre; Auclair, Christiane; Barreau, Christian; Al Hajj, Charbel; Debieu, Daniele

2008-01-01

102

Infection dynamics and acute phase response of an Actinobacillus pleuropneumoniae field isolate of moderate virulence in pigs.  

PubMed

Actinobacillus pleuropneumoniae, the causative agent of porcine contagious pleuropneumonia (PCP), causes significant economic losses associated mainly with growth stunting of animals. Although serotypes can be distinguished according to their virulence, most of the studies are focused in A. pleuropneumoniae infections with virulent serotypes. There is little information regarding the role of acute phase proteins (APPs) and proinflammatory cytokines in infections with isolates of mild or moderate virulence. Thus, the present study aims to evaluate the kinetics of infection with an A. pleuropneumoniae serotype 6 (Ap6) field isolate of moderate virulence and the changes in the serum concentration of specific antibodies and different APPs and proinflammatory cytokines. Control animals showed no clinical signs or lesions throughout the study. Infected animals showed increased rectal temperature, respiratory distress and depression from 24hpi, and typical gross and microscopic lesions of PCP from 6hpi onwards. Ap6 was isolated from nasal swabs of four out of five inoculated animals at 24hpi, and from nasal swabs, tonsil and lung samples from all inoculated animals at 72hpi. Specific antibodies against Ap6 or changes in the serum concentration of IL-1?, IL-10 and TNF-? were not detected throughout the study. The serum concentration of IL-6 increased from 6hpi as well as serum A amyloid, C-reactive protein and haptoglobin from 24hpi onwards. Our results highlight the onset of the acute phase response after the infection with a field isolate of A. pleuropneumoniae of moderate virulence from 24hpi onwards which may be of interest in the study of the pathogenesis of this disease. PMID:25201629

Gómez-Laguna, Jaime; Islas, Armando; Muñoz, Dennis; Ruiz, Alvaro; Villamil, Aura; Carrasco, Librado; Quezada, Manuel

2014-10-10

103

MAGNETIC FIELD IN THE ISOLATED MASSIVE DENSE CLUMP IRAS 20126+4104  

SciTech Connect

We measured polarized dust emission at 350 {mu}m toward the high-mass star-forming massive dense clump IRAS 20126+4104 using the SHARC II Polarimeter, SHARP, at the Caltech Submillimeter Observatory. Most of the observed magnetic field vectors agree well with magnetic field vectors obtained from a numerical simulation for the case when the global magnetic field lines are inclined with respect to the rotation axis of the dense clump. The results of the numerical simulation show that rotation plays an important role on the evolution of the massive dense clump and its magnetic field. The direction of the cold CO 1-0 bipolar outflow is parallel to the observed magnetic field within the dense clump as well as the global magnetic field, as inferred from optical polarimetry data, indicating that the magnetic field also plays a critical role in an early stage of massive star formation. The large-scale Keplerian disk of the massive (proto)star rotates in an almost opposite sense to the clump's envelope. The observed magnetic field morphology and the counterrotating feature of the massive dense clump system provide hints to constrain the role of magnetic fields in the process of high-mass star formation.

Shinnaga, Hiroko; Phillips, Thomas G. [California Institute of Technology Submillimeter Observatory, 111 Nowelo Street, Hilo, HI 96720 (United States); Novak, Giles [Department of Physics and Astronomy, Northwestern University, 633 Clark Street Evanston, IL 60208 (United States); Vaillancourt, John E. [Stratospheric Observatory for Infrared Astronomy, Universities Space Research Association, NASA Ames Research Center, Moffet Field, CA 94035 (United States); Machida, Masahiro N. [Department of Earth and Planetary Sciences, Faculty of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Kataoka, Akimasa [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Tomisaka, Kohji [National Astronomical Observatory of Japan and Department of Astronomy, School of Physical Sciences, Graduate University for Advanced Studies (SOKENDAI), Osawa 2-21-1, Mitaka, Tokyo 181-8588 (Japan); Davidson, Jacqueline; Houde, Martin [School of Physics, University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Perth (Australia); Dowell, C. Darren [Jet Propulsion Laboratory, California Institute of Technology, MS 169-506, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Leeuw, Lerothodi [SETI Institute, 515 North Whisman Avenue, Mountain View, CA 94043 (United States)

2012-05-10

104

Identification of a novel equine infectious anemia virus field strain isolated from feral horses in southern Japan.  

PubMed

Although equine infectious anemia (EIA) was described more than 150 years ago, complete genomic sequences have only been obtained from two field strains of EIA virus (EIAV), EIAV(Wyoming) and EIAV(Liaoning). In 2011, EIA was detected within the distinctive feral Misaki horse population that inhabits the Toi-Cape area of southern Japan. Complete proviral sequences comprising a novel field strain were amplified directly from peripheral blood of one of these EIAV-infected horses and characterized by nucleotide sequencing. The complete provirus of Miyazaki2011-A strain is 8208 bp in length with an overall genomic organization typical of EIAV. However, this field isolate possesses just 77.2 and 78.7?% nucleotide sequence identity with the EIAV(Wyoming) and EIAV(Liaoning) strains, respectively, while similarity plot analysis suggested all three strains arose independently. Furthermore, phylogenetic studies using sequences obtained from all EIAV-infected Misaki horses against known viral strains strongly suggests these Japanese isolates comprise a separate monophyletic group. PMID:23100364

Dong, Jian-Bao; Zhu, Wei; Cook, Frank R; Goto, Yoshitaka; Horii, Yoichiro; Haga, Takeshi

2013-02-01

105

Comparison and genomic sizing of Escherichia coli O157:H7 isolates by pulsed-field gel electrophoresis.  

PubMed Central

Genomic DNAs of Escherichia coli O157:H7 strains isolated from patients and food samples were analyzed by pulsed-field gel electrophoresis. The rare-cutting endonucleases SfiI and XbaI generated 6 and 10 distinct genomic profiles, respectively, for the 22 strains analyzed, indicating that this technique may find application for epidemiologic studies. Summation of XbaI fragments from five E. coli O157:H7 strains estimated the genomic length at ca. 4.7 Mb. Images PMID:8215383

Harsono, K D; Kaspar, C W; Luchansky, J B

1993-01-01

106

Paralcaligenes ureilyticus gen. nov., sp. nov. isolated from soil of a Korean ginseng field  

Microsoft Academic Search

A bacterial strain, designated GR24-5T, was isolated from soil cultivated with Korean ginseng. Cells were Gram-negative, strictly aerobic, catalase- and oxidase-positive,\\u000a non-spore-forming motile rods. Based on the 16S rRNA gene sequence, strain GR24-5T could be assigned to the family Alcaligenaceae. Strain GR24-5T showed the highest sequence similarities with Parapusillimonas granuli Ch07T (97.1%), Pusillimonas noertemannii BN9T (96.9%), Pigmentiphaga kullae DSM 13608T

Soo-Jin Kim; Seung-Hee Yoo; Hang-Yeon Weon; Yi-Seul Kim; Rangasamy Anandham; Jang-Sun Suh; Soon-Wo Kwon

2011-01-01

107

Isolated-core excitations in strong electric fields. III. The Ba 6p{sub j}nk series  

SciTech Connect

The cross section for isolated-core excitation (ICE) of barium 6p{sub j}n{sup '}k{sup '} autoionizing states from 6snk Stark levels has been measured as a function of applied electric-field strength. For the most part, states that are well mixed by the applied field have nearly Lorentzian line shapes indicating predominant ICE of a single autoionizing resonance with n{sup '}=n and k{sup '}=k. Small non-Lorentzian shake-up features in the wings of the lines are examined in detail using high laser power to depletion broaden the main resonance and amplify the wings of the line shapes. While analogous shake-up features in zero-field ICE spectra are easily described theoretically, attempts to reproduce the spectra observed in a field generally fail to provide good agreement. Finally, significant differences in excitation of Ba{sup +} 6p{sub 1/2} rather than Ba{sup +} 6p{sub 3/2} cores are observed. (c) 2000 The American Physical Society.

Jones, R. R. [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)] [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States); Lyons, B. J. [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)] [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States); Baig, M. A. [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)] [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States); Djambova, Svetlana T. [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)] [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States); Gallagher, T. F. [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)] [Department of Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)

2000-09-01

108

WIPP (Waste Isolation Pilot Plant) horizon free field fluid transport characteristics  

SciTech Connect

This report describes the first attempt to measure the free field brine transport characteristics of the host rock. The data, which have been used to estimate the brine permeability, also suggest free field pore pressure values. One borehole was located in a competent predominantly halite bed with the test region positioned approximately nine meters from the rib. A second borehole intersected Marker Bed 139, which is a one meter thick fractured predominantly anhydrite layer. For this second borehole, the test region was positioned approximately 12 meters from the invert/rib intersection. A description of the tests provided in Section 2. Data obtained during these tests are described in Section 3. Analysis of these data and the associated uncertainties inherent in the data interpretation are presented in Section 4. Test results are given in Section 5. Conclusions are provided in Section 6. 13 refs., 65 figs.

Peterson, E.W.; Lagus, P.L.; Lie, K.

1987-12-01

109

Discovery of a candidate old, isolated neutron star in the field of a galactic cirrus cloud  

NASA Technical Reports Server (NTRS)

New x-ray optical, and radio observations of the bright, unidentified x-ray source MS 0317.7-6647 are presented suggesting that this source is a likely compact stellar remnant. As part of the Einstein Extended Medium Sensivity Survey, this source was discovered serendipitously in the Einstein Imaging Proportional Counter pointing towards the nearby (4.5 Mpc) spiral galaxy NGC 1313. The very high x-ray to optical flux ratio, pointlike ROSAT HRI detection, and extremely soft component in the x-ray spectrum of MS 0317.7-6647 eliminate all the usual classes of optical counterparts to faint x-ray sources except for a very massive x-ray binary (and black hole candidate) in NGC 1313, a nearby, companionless pulsar similar to Geminga, or a very nearby ( approximately 100 pc) isolated, old neutron star slowly accreting interstellar matter onto its magnetic poles. The presence of an IR cirrus cloud which shadows the approximately 0.25 keV x-ray background in this direction supports the latter possibilty.

Stocke, John T.; Wang, Q. Daniel; Perlman, Eric S.; Donahue, Megan E.; Schachter, Jonathan F.

1995-01-01

110

Field and laboratory testing of seal materials proposed for the Waste Isolation Pilot Plant  

SciTech Connect

The Small Scale Seal Performance Tests (SSSPT) were a series of in situ tests designed to evaluate the feasibility of various materials for sealing purposes. Testing was initiated in 1985 and concluded in 1995. Materials selected for the SSSPT included salt-saturated concrete, a 50%/50% mixture of crushed salt and bentonite, bentonite, and crushed salt. This paper presents a summary of the SSSPT field program, results of the in situ testing, and a discussion of post-testing laboratory studies of salt-saturated concrete. Results of the SSSPT support the use of salt-saturated concrete, compacted bentonite clay, and compacted crushed salt as sealing materials for the WIPP.

Knowles, M.K. [Sandia National Labs., Albuquerque, NM (United States); Howard, C.L. [RE/SPEC, Inc., Carlsbad, NM (United States)

1996-02-05

111

Pseudoxanthomonas icgebensis sp. nov., isolated from the midgut of Anopheles stephensi field-collected larvae.  

PubMed

A Gram-negative, aerobic, golden yellow, rod-shaped bacterium, a strain designated ICGEB-L15(T), was isolated from the larval midgut of Anopheles stephensi captured in District Jhajjar, Haryana, India. The strain ICGEB-L15(T) grows at 30-50°C (optimum 30-37°C), pH 6.5-8.5 (optimum 7.0-8.0) and in the presence of 2% NaCl. The major fatty acids were iso-C(15:0) (22.5% of total fatty acid), anteiso-C(15:0) (16.5%), iso-C(17:1) 9c (10.3%), iso-C(16:0) (7.3%), C(16:0) (6.1%), and iso-C(11:0) (5.3%). The strain showed the highest 16S rRNA gene sequence similarities with the type strains Pseudoxanthomonas daejeonensis KCTC 12207(T) (97.4%), Pseudoxanthomonas kaohsiungensis J36(T) (97.17%), and Pseudoxanthomonas mexicana AMX 26B(T) (97.11%). The DNA relatedness between ICGEB-L15(T) and Pseudoxanthomonas daejeonensis KCTC 12207(T), Pseudoxanthomonas kaohsiungensis J36(T) and Pseudoxanthomonas mexicana AMX 26B(T) was 24.5%, 28.2%, and 33.6%, respectively. The G+C content of genomic DNA was 69.9 mol%. The major isoprenoid quinone of strain ICGEB-L15(T) was Q-8. The strain ICGEB-L15(T) represents a novel species of the genus Pseudoxanthomonas based on physiological, biochemical and phylogenetic properties; therefore, the name Pseudoxanthomonas icgebensis sp. nov. is proposed. The type strain is ICGEB-L15(T) (=KACC 14090(T) =DSM 22536(T)). PMID:21046337

Rani, Asha; Sharma, Anil; Adak, Tridibes; Bhatnagar, Raj K

2010-10-01

112

Paralcaligenes ureilyticus gen. nov., sp. nov. isolated from soil of a Korean ginseng field.  

PubMed

A bacterial strain, designated GR24-5(T), was isolated from soil cultivated with Korean ginseng. Cells were Gram-negative, strictly aerobic, catalase- and oxidase-positive, non-spore-forming motile rods. Based on the 16S rRNA gene sequence, strain GR24-5(T) could be assigned to the family Alcaligenaceae. Strain GR24-5(T) showed the highest sequence similarities with Parapusillimonas granuli Ch07(T) (97.1%), Pusillimonas noertemannii BN9(T) (96.9%), Pigmentiphaga kullae DSM 13608(T) (96.5%), and Castellaniella defragrans 54Pin(T) (96.3%). Strain GR24-5(T) demonstrated a low DNA-DNA relatedness (23%) with P. granuli Ch07(T). The major respiratory quinone is ubiquinone 8 (Q-8) and the major fatty acids are C(16:0), C(17:0) cyclo, and summed feature 1 (C(14:0) 3-OH/iso-C(16:1) I/C(12:0) aide). Putrescine, spermidine, and 2-hydroxyputrescine are the major polyamines. The major polar lipids are phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, di-phosphatidylglycerol, and an unknown aminophospholipid. Polar lipid patterns of strain GR24-5(T) were unique in having a large amount of phosphatidylmethylethanolamine. Based on phylogenetic analysis and physiological and biochemical characteristics, strain GR245(T) represents a novel genus and species, for which the name Paralcaligenes ureilyticus gen. nov., sp. nov. is proposed. The type strain of P. aralcaligenes ureilyticus is GR24-5(T) (=KACC 13888 =DSM 24591(T)). PMID:21717340

Kim, Soo-Jin; Yoo, Seung-Hee; Weon, Hang-Yeon; Kim, Yi-Seul; Anandham, Rangasamy; Suh, Jang-Sun; Kwon, Soon-Wo

2011-06-01

113

Limited diversity of measles field isolates after a national immunization day in Burkina Faso: progress from endemic to epidemic transmission?  

PubMed

Despite recent National Immunization Days in Burkina Faso, the rural province of Houët reported >400 measles cases in 2001 (82% not vaccinated). Phylogenetic analysis of 58 measles virus field isolates plus the first sequences from the Democratic Republic of the Congo and the Republic of Congo are reported. All viruses were genotype B3, which is common in the region. In Houët, there were two geographically confined genetic variants, suggesting two independent importation events. Strain diversity in Houët (1.5%) and the Congos was limited in comparison with Ibadan, Nigeria (4.6%), where measles is endemic. Strain variability, assessed by heteroduplex mobility assay, confirmed these findings. Despite large local pools of susceptible persons even after several rounds of vaccination, the limited strain diversity suggests that parts of rural Burkina Faso may be moving from an endemic to an epidemic transmission pattern of measles virus. PMID:12721926

Mulders, Mick N; Nebie, Yacouba K; Fack, Fred; Kapitanyuk, Tetyana; Sanou, Oumar; Valéa, Dianne C; Muyembe-Tamfum, Jean-Jacques; Ammerlaan, Wim; Muller, Claude P

2003-05-15

114

Better than 10 mA field emission from an isolated structure emitter of a metal oxide/CNT composite.  

PubMed

An isolated structure emitter is presented that can deliver a field emission better than 10 mA, a level that is by far the highest ever reported. A composite of CNT (carbon nanotube) and WO(3) is used to grow the point emitter by a crystal-like growth technique. The head of the grown needle that is the emitter is removed by electric discharge machining (EDM). The EDM treatment not only controls the length of the emitter as desired but also makes the tip of the emitter uniform. The thermal heat due to EDM treatment leads to the formation of a tungsten carbide phase, which results in a 3 orders of magnitude reduction in contact resistance. The point emitter is robust in its stability, as evidenced by its on-time resilience against a severe bias test. PMID:21171631

Kim, Wal Jun; Lee, Jeong Seok; Lee, Seung Min; Song, Ki Young; Chu, Chong Nam; Kim, Yong Hyup

2011-01-25

115

In vitro sensitivity testing of Leishmania clinical field isolates: preconditioning of promastigotes enhances infectivity for macrophage host cells.  

PubMed

Diagnostic material from patients with leishmaniasis is generally available as promastigotes, and proper testing for susceptibility to first-line drugs by the intracellular amastigote assay is frequently hampered by the poor infectivity of the promastigotes for the macrophage host cell. Several conditions for optimization of the in vitro metacyclogenesis and cell infectivity of Leishmania donovani, L. guyanensis, and L. braziliensis field strains obtained from patients receiving standard antimony medication were investigated. Triggering log-phase promastigotes to become amastigote-like by increasing the temperature or acidifying the culture medium was not successful. Adequate metacyclogenesis and the highest levels of macrophage infection were obtained after 5-day-old late-log-phase promastigote cultures were preconditioned at 25 degrees C to pH 5.4 for 24 h in Schneider's medium prior to infection. The susceptibility assay with primary peritoneal mouse macrophages included pentavalent antimony (Sb(V); sodium stibogluconate), trivalent antimony (Sb(III); potassium antimonyl tartrate), miltefosine, and the experimental drug PX-6518. All strains were sensitive to miltefosine (50% inhibitory concentration [IC(50)] < 10 microM) and PX-6518 (IC(50) < 2 microg/ml) but showed distinct susceptibility to Sb(V) and/or Sb(III), depending on whether they were derived from cured, relapse, or nonresponder patients. Within the available set of Leishmania species and strains, simultaneous Sb(V)-Sb(III) resistance was clearly associated with treatment failure; however, a larger set of isolates is still needed to judge the predictive value of Sb(V)-Sb(III) susceptibility profiling on treatment outcome. In conclusion, the proposed conditioning protocol further contributes toward a more standardized laboratory model for evaluation of the drug sensitivities of field isolates. PMID:19752271

da Luz, Raquel Inocêncio; Vermeersch, Marieke; Dujardin, Jean-Claude; Cos, Paul; Maes, Louis

2009-12-01

116

In Vitro Susceptibility of Field Isolates of Leishmania donovani to Miltefosine and Amphotericin B: Correlation with Sodium Antimony Gluconate Susceptibility and Implications for Treatment in Areas of Endemicity  

Microsoft Academic Search

Indian Leishmania donovani isolates (n 19) from regional zones representing various levels of antimony resistance displayed significantly (P < 0.01) correlated results with respect to in vitro susceptibility to the antileishmanial drugs sodium antimony gluconate, amphotericin B, and Miltefosine, raising the possibility of cross-resistance mechanisms operating in the field isolates. The results of gene expression analysis of LdMT and LdRos3

Dhiraj Kumar; Arpita Kulshrestha; Ruchi Singh; Poonam Salotra

2009-01-01

117

Comparison of Staphylococcus aureus Isolates from Bovine and Human Skin, Milking Equipment, and Bovine Milk by Phage Typing, Pulsed-Field Gel Electrophoresis, and Binary Typing  

PubMed Central

Staphylococcus aureus isolates (n = 225) from bovine teat skin, human skin, milking equipment, and bovine milk were fingerprinted by pulsed-field gel electrophoresis (PFGE). Strains were compared to assess the role of skin and milking equipment as sources of S. aureus mastitis. PFGE of SmaI-digested genomic DNA identified 24 main types and 17 subtypes among isolates from 43 herds and discriminated between isolates from bovine teat skin and milk. Earlier, phage typing (L. K. Fox, M. Gershmann, D. D. Hancock, and C. T. Hutton, Cornell Vet. 81:183-193, 1991) had failed to discriminate between isolates from skin and milk. Skin isolates from humans belonged to the same pulsotypes as skin isolates from cows. Milking equipment harbored strains from skin as well as strains from milk. We conclude that S. aureus strains from skin and from milk can both be transmitted via the milking machine, but that skin strains are not an important source of intramammary S. aureus infections in dairy cows. A subset of 142 isolates was characterized by binary typing with DNA probes developed for typing of human S. aureus. Typeability and overall concordance with epidemiological data were lower for binary typing than for PFGE while discriminatory powers were similar. Within several PFGE types, binary typing discriminated between main types and subtypes and between isolates from different herds or sources. Thus, binary typing is not suitable as replacement for PFGE but may be useful in combination with PFGE to refine strain differentiation. PMID:12409348

Zadoks, R. N.; van Leeuwen, W. B.; Kreft, D.; Fox, L. K.; Barkema, H. W.; Schukken, Y. H.; van Belkum, A.

2002-01-01

118

Seismic Protection of Bridge Structures Using Shape Memory Alloy-Based Isolation Systems against Near-Field Earthquakes  

E-print Network

-dependent material response while it remains simple enough to carry out numerical simulations. Next, parametric studies are conducted to investigate the effectiveness of two SMA-based isolation systems, namely superelastic-friction base isolator (S-FBI) system...

Ozbulut, Osman Eser

2012-02-14

119

Higher incidence of Eimeria spp. field isolates sensitive for diclazuril and monensin associated with the use of live coccidiosis vaccination with paracox-5 in broiler farms.  

PubMed

Twenty European Eimeria spp. field isolates were subjected to an anticoccidial sensitivity test (AST). The anticoccidial drugs tested were diclazuril (Clinacox) and monensin (Elancoban). The assay was performed in a battery cage trial. Infected medicated birds were compared with an unmedicated control group. Coccidial lesion scores and oocyst shedding were used as parameters. The results of the AST show that resistance is common amongst coccidiosis field isolates, especially Eimeria acervulina (68% and 53% resistance for diclazuril and monensin, respectively). Resistance is less frequent amongst Eimeria maxima (38% and 50% resistance for diclazuril and monensin, respectively) and Eimeria tenella isolates (23% and 38% resistance for diclazuril and monensin, respectively). A highly significant influence of the coccidiosis prevention program (live coccidiosis vaccination with Paracox-5 vs. anticoccidial drugs in feed) on the sensitivity patterns of Eimeria spp. field isolates for both diclazuril (P= 0.000) and monensin (P= 0.001) was found. Further, when looking at the single species and each anticoccidial drug level, significantly more sensitivity of E. acervulina for monensin (P= 0.018), E. maxima for diclazuril (P = 0.009), and E. tenella for diclazuril (P = 0.007) was found in isolates originating from vaccinated flocks. Moreover, for E. acervulina and diclazuril, E. maxima and monensin, and E. tenella and monensin a trend toward higher sensitivity of isolates for these products was found when live coccidiosis vaccination was applied. The present study shows that sensitivity for the anticoccidial drugs diclazuril and monensin is more frequent in Eimeria spp. field isolates originating from broiler farms where a coccidiosis vaccination policy is followed. PMID:17039846

Peek, H W; Landman, W J M

2006-09-01

120

Plasmid Profile and Pulsed-Field Gel Electrophoresis Analysis of Salmonella enterica Isolates from Humans in Turkey  

PubMed Central

This study was conducted for typing Salmonella enterica subspecies enterica strains in Turkey using pulsed–field gel electrophoresis (PFGE) and plasmid DNA profile analysis. Fourty-two strains were isolated from clinical samples obtained from unrelated patients with acute diarrhea. The samples were collected from state hospitals and public health laboratories located at seven provinces in different regions of Turkey at different times between 2004 and 2010. The strains were determined to belong to 4 different serovars. The Salmonella enterica strains belonged to the serovars Salmonella Enteritidis (n?=?23), Salmonella Infantis (n?=?14), Salmonella Munchen (n?=?2), and Salmonella Typhi (n?=?3). Forty-two Salmonella enterica strains were typed with PFGE methods using XbaI restriction enzyme and plasmid analysis. At the end of typing, 11 different PFGE band profiles were obtained. Four different PFGE profiles (type 1, 4, 9, and 10) were found among serotype S. Enteritidis species, 3 different PFGE profiles (type 3, 5, 6) were found among S. Infantis species, 2 different PFGE profiles were found among S. Typhi species (type 2 and 11), and 2 different PFGE profiles were found among S. Munchen species (type 7, 8). The UPGMA dendrogram was built on the PFGE profiles. In this study, it was determined that 4 strains of 42 Salmonella enterica strains possess no plasmid, while the isolates have 1–3 plasmids ranging from 5.0 to 150 kb and making 12 different plasmid profiles (P1–P12). In this study, we have applied the analysis of the PFGE patterns and used bioinformatics methods to identify both inter and intra serotype relationships of 4 frequently encountered serotypes for the first time in Turkey. PMID:24852084

Ozdemir, Kerem; Acar, Sumeyra

2014-01-01

121

Complete Genome Sequence of a Field Strain of Peste des Petits Ruminants Virus Isolated during 2010-2014 Epidemics in Senegal  

PubMed Central

Peste des petits ruminants virus (PPRV) infection is expanding and results in regular epizootic activities in Africa, the Middle East, and Asia. Here, we report the complete genome sequence of a field strain of PPRV isolated in Senegal (SnDk11I13) in 2013.

Salami, Habib; Croville, Guillaume; Kwiatek, Olivier; Mariette, Jerome; Klopp, Christophe; Valiere, Sophie; Guerin, Jean-Luc; Lo, Moustapha; Thiongane, Yaya; Albina, Emmanuel

2014-01-01

122

Insecticide Resistance Alleles Affect Vector Competence of Anopheles gambiae s.s. for Plasmodium falciparum Field Isolates  

PubMed Central

The widespread insecticide resistance raises concerns for vector control implementation and sustainability particularly for the control of the main vector of human malaria, Anopheles gambiae sensu stricto. However, the extent to which insecticide resistance mechanisms interfere with the development of the malignant malaria parasite in its vector and their impact on overall malaria transmission remains unknown. We explore the impact of insecticide resistance on the outcome of Plasmodium falciparum infection in its natural vector using three An. gambiae strains sharing a common genetic background, one susceptible to insecticides and two resistant, one homozygous for the ace-1R mutation and one for the kdr mutation. Experimental infections of the three strains were conducted in parallel with field isolates of P. falciparum from Burkina Faso (West Africa) by direct membrane feeding assays. Both insecticide resistant mutations influence the outcome of malaria infection by increasing the prevalence of infection. In contrast, the kdr resistant allele is associated with reduced parasite burden in infected individuals at the oocyst stage, when compared to the susceptible strain, while the ace-1R resistant allele showing no such association. Thus insecticide resistance, which is particularly problematic for malaria control efforts, impacts vector competence towards P. falciparum and probably parasite transmission through increased sporozoite prevalence in kdr resistant mosquitoes. These results are of great concern for the epidemiology of malaria considering the widespread pyrethroid resistance currently observed in Sub-Saharan Africa and the efforts deployed to control the disease. PMID:23704944

Alout, Haoues; Ndam, Nicaise Tuikue; Sandeu, Marcel Maurice; Djegbe, Innocent; Chandre, Fabrice; Dabire, Roch Kounbobr; Djogbenou, Luc Salako; Corbel, Vincent; Cohuet, Anna

2013-01-01

123

Research Article Isolation and Characterization of a Novel Facultative Anaerobic Filamentous Fungus from Japanese Rice Field Soil  

E-print Network

novel filamentous fungus strain designated RB-1 was isolated into pure culture from Japanese rice field soil through an anaerobic role tube technique. The strain is a mitosporic fungus that grows in both aerobic and strict anaerobic conditions using various mono-, di-, tri-, and polysaccharides with acetate and ethanol productions. The amount of acetate produced was higher than that of ethanol in both aerobic and anaerobic cultures. The characteristic verrucose or punctuate conidia of RB-1 closely resembled thoseofsomestrainsofthegenusThermomyces, a thermophilic or mesophilic anamorphic ascomycete. However, based on phylogenetic analysis with the small subunit (SSU) and large subunit (LSU) rDNA sequences, RB-1 was characterized as a member of the class Lecanoromycetes of the phylum Ascomycota. Currently, RB-1 is designated as an anamorphic ascomycete and is phylogenetically considered an incertae sedis within the class Lecanoromycetes. Copyright © 2009 Akio Tonouchi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1.

Akio Tonouchi

124

Insecticide resistance alleles affect vector competence of Anopheles gambiae s.s. for Plasmodium falciparum field isolates.  

PubMed

The widespread insecticide resistance raises concerns for vector control implementation and sustainability particularly for the control of the main vector of human malaria, Anopheles gambiae sensu stricto. However, the extent to which insecticide resistance mechanisms interfere with the development of the malignant malaria parasite in its vector and their impact on overall malaria transmission remains unknown. We explore the impact of insecticide resistance on the outcome of Plasmodium falciparum infection in its natural vector using three An. gambiae strains sharing a common genetic background, one susceptible to insecticides and two resistant, one homozygous for the ace-1(R) mutation and one for the kdr mutation. Experimental infections of the three strains were conducted in parallel with field isolates of P. falciparum from Burkina Faso (West Africa) by direct membrane feeding assays. Both insecticide resistant mutations influence the outcome of malaria infection by increasing the prevalence of infection. In contrast, the kdr resistant allele is associated with reduced parasite burden in infected individuals at the oocyst stage, when compared to the susceptible strain, while the ace-1 (R) resistant allele showing no such association. Thus insecticide resistance, which is particularly problematic for malaria control efforts, impacts vector competence towards P. falciparum and probably parasite transmission through increased sporozoite prevalence in kdr resistant mosquitoes. These results are of great concern for the epidemiology of malaria considering the widespread pyrethroid resistance currently observed in Sub-Saharan Africa and the efforts deployed to control the disease. PMID:23704944

Alout, Haoues; Ndam, Nicaise Tuikue; Sandeu, Marcel Maurice; Djégbe, Innocent; Chandre, Fabrice; Dabiré, Roch Kounbobr; Djogbénou, Luc Salako; Corbel, Vincent; Cohuet, Anna

2013-01-01

125

A new senescence-inducing mitochondrial linear plasmid in field-isolated Neurospora crassa strains from India.  

PubMed

Several field-collected strains of Neurospora crassa from the vicinity or Aarey, Bombay, India, are prone to precocious senescence and death. Analysis of one strain, Aarely-1e, demonstrated that the genetic determinants for the predisposition to senescence are maternally inherited. The senescence-prone strains contain a 7-kb, linear, mitochondrial DNA plasmid, maranhar, which is not present in long-lived isolates from the same geographical location. The maranhar plasmid has inverted terminal repeats with protein covalently bound at the 5' termini. Molecular hybridization experiments have demonstrated no substantial DNA sequence homology between the plasmid and the normal mitochondrial (mtDNA) and nuclear genomes of long-lived strains of N. crassa. Integrated maranhar sequences were detected in the mtDNAs of two cultures derived from Aarey-1e, and mtDNAs with the insertion sequences accumulated during subculturing. Nucleotide sequence analysis of cloned fragments of the two insertion sequences demonstrates that they are flanked by long inverted repeats of mtDNA. The senescence syndrome of the maranhar strains, and the mode of integration of the plasmid, are reminiscent of those seen in the kalilo strains of N. intermedia. Nonetheless, there is no detectable nucleotide sequence homology between the maranhar and kalilo plasmids. PMID:1648454

Court, D A; Griffiths, A J; Kraus, S R; Russell, P J; Bertrand, H

1991-02-01

126

Cloning and expression of an antifungal chitinase gene of a novel Bacillus subtilis isolate from Taiwan potato field.  

PubMed

A chitinase producing Bacillus subtilis CHU26 was isolated from Taiwan potato field. This strain exhibited a strong extra-cellular chitinase activity on the colloidal chitin containing agar plate, and showed a potential inhibit activity against phytopathogen, Rhizoctonia solani. The gene encoding chitinase (chi18) was cloned from the constructed B. subtilis CHU26 genomic DNA library. The chi18 consisted of an open reading frame of 1791 nucleotides and encodes 595 amino acids with a deduced molecular weight of 64kDa, next to a promoter region containing a 9 base pair direct repeat sequence (ATTGATGAA). The deduced amino acid sequence of the chitinase from Bacillus subtilis CHU26 exhibits 62% and 81% similarity to those from B. circulans WL-12 and B. licheniformis, respectively. Subcloned chi18 into vector pGEM3Z and pYEP352 to construct recombinant plasmid pGCHI18 and pYCHI18, respectively, chitinase activity could be observed on the colloidal chitin agar plate from recombinant plasmid containing Escherichia coli transformant. Cell-free culture broth of pYCHI18 containing E. coli transformant decreased R. solani pathogenic activity more than 90% in the antagonistic test on the radish seedlings (Raphanus sativus Linn.). PMID:18824348

Yang, Chi-Yea; Ho, Yi-Cheng; Pang, Jen-Chieh; Huang, Shiang-Suo; Tschen, Johannes Seng-Ming

2009-02-01

127

The Cytochrome P450 Lanosterol 14?-Demethylase Gene Is a Demethylation Inhibitor Fungicide Resistance Determinant in Monilinia fructicola Field Isolates from Georgia? †  

PubMed Central

Resistance in Monilinia fructicola to demethylation inhibitor (DMI) fungicides is beginning to emerge in North America, but its molecular basis is unknown. Two potential genetic determinants of DMI fungicide resistance including the 14?-demethylase gene (MfCYP51) and the ATP-binding cassette transporter gene MfABC1, were investigated in six resistant (DMI-R) and six sensitive (DMI-S) field isolates. No point mutations leading to an amino acid change were found in the MfCYP51 gene. The constitutive expression of the MfCYP51 gene in DMI-R isolates was significantly higher compared to DMI-S isolates. Gene expression was not induced in mycelium of DMI-R or DMI-S isolates treated with 0.3 ?g of propiconazole/ml. A slightly higher average MfCYP51 copy number value was detected in DMI-R isolates (1.35) compared to DMI-S isolates (1.13); however, this difference could not be verified in Southern hybridization experiments or explain the up to 11-fold-increased MfCYP51 mRNA levels in DMI-R isolates. Analysis of the upstream nucleotide sequence of the MfCYP51 gene revealed a unique 65-bp repetitive element at base pair position ?117 from the translational start site in DMI-R isolates but not in DMI-S isolates. This repetitive element contained a putative promoter and was named Mona. The link between Mona and the DMI resistance phenotype became even more apparent after studying the genetic diversity between the isolates. In contrast to DMI-S isolates, DMI-R isolates contained an MfCYP51 gene of identical nucleotide sequence associated with Mona. Still, DMI-R isolates were not genetically identical as revealed by Microsatellite-PCR analysis. Also, real-time PCR analysis of genomic DNA indicated that the relative copy number of Mona among DMI-S and DMI-R isolates varied, suggesting its potential for mobility. Interestingly, constitutive expression of the MfABC1 gene in DMI-R isolates was slightly lower than that of DMI-S isolates, but expression of the MfABC1 gene in DMI-R isolates was induced in mycelium after propiconazole treatment. Therefore, the MfABC1 gene may play a minor role in DMI fungicide resistance in M. fructicola. Our results strongly suggest that overexpression of the MfCYP51 gene is an important mechanism in conferring DMI fungicide resistance in M. fructicola field isolates from Georgia and that this overexpression is correlated with Mona located upstream of the MfCYP51 gene. PMID:18024679

Luo, Chao-Xi; Schnabel, Guido

2008-01-01

128

Diversity of pulsed-field gel electrophoresis pulsotypes, serovars, and antibiotic resistance among Salmonella isolates from wild amphibians and reptiles in the California Central Coast.  

PubMed

A survey of cold-blooded vertebrates and associated surface waters in a produce-growing region on the Central California Coast was done between May and September 2011 to determine the diversity of Salmonella. Samples from 460 amphibians and reptiles and 119 water samples were collected and cultured for Salmonella. Animals sampled were frogs (n=331), lizards (n=59), newts (n=5), salamanders (n=6), snakes (n=39), and toads (n=20). Salmonella was isolated from 37 individual animals, including frogs, lizards, snakes, and toads. Snakes were the most likely to contain Salmonella, with 59% testing positive followed by 15.3% of lizards, 5% of toads, and 1.2% of frogs. Fifteen water samples (12.6%) were positive. Twenty-two different serovars were identified, and the majority of isolates were S. enterica subsp. IIIb, with subsp. I, II, and IIIa also found. The serovar isolated most frequently was S. enterica subsp. IIIb 16:z??:e,n,x,z??, from snakes and frogs in five different locations. S. enterica subsp. I serovar Typhimurium and the monophasic I 6,8:d:- were isolated from water, and subspecies I Duisburg and its variants were found in animals and water. Some samples contained more than one type of Salmonella. Analysis of pulsed-field gel electrophoresis pulsotypes indicated that some strains persisted in animals and water collected from the same location. Sixty-six isolates displayed antibiotic resistance, with 27 isolates resistant to more than one antibiotic, including a subspecies IIIb isolate from snake having resistance to five different antibiotics. Twenty-three isolates were resistant to more than one class of antibiotic, and six isolates were resistant to three classes. While these subspecies of IIIa and IIIb cause fewer instances of human illness, they may serve as reservoirs of antibiotic resistance, determinants in the environment, and be sources of contamination of leafy greens associated with product recalls. PMID:23577627

Gorski, Lisa; Jay-Russell, Michele T; Liang, Anita S; Walker, Samarpita; Bengson, Yingjia; Govoni, Jessica; Mandrell, Robert E

2013-06-01

129

High Genetic Diversity of Enterococcus faecium and Enterococcus faecalis Clinical Isolates by Pulsed-Field Gel Electrophoresis and Multilocus Sequence Typing from a Hospital in Malaysia  

PubMed Central

Little is known on the genetic relatedness and potential dissemination of particular enterococcal clones in Malaysia. We studied the antibiotic susceptibility profiles of Enterococcus faecium and Enterococcus faecalis and subjected them to pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). E. faecium and E. faecalis displayed 27 and 30 pulsotypes, respectively, and 10 representative E. faecium and E. faecalis isolates (five each) yielded few different sequence types (STs): ST17 (2 isolates), ST78, ST203, and ST601 for E. faecium, and ST6, ST16, ST28, ST179, and ST399 for E. faecalis. Resistance to tazobactam-piperacillin and ampicillin amongst E. faecium isolates was highly observed as compared to E. faecalis isolates. All of the isolates were sensitive to vancomycin and teicoplanin. The presence of epidemic and nosocomial strains of selected E. faecium STs: 17, 78, and 203 and E. faecalis ST6 as well as high rates of resistance to multiple antibiotics amongst E. faecium isolates is of a particular concern. PMID:23819125

Weng, Poh Leng; Ramli, Ramliza; Shamsudin, Mariana Nor; Cheah, Yoke-Kqueen; Hamat, Rukman Awang

2013-01-01

130

Overexpression of ShCYP51B and ShatrD in Sclerotinia homoeocarpa isolates exhibiting practical field resistance to a demethylation inhibitor fungicide.  

PubMed

We investigated genetic factors that govern the reduced propiconazole sensitivity of Sclerotinia homoeocarpa field isolates collected during a 2-year field efficacy study on dollar spot disease of turf in five New England sites. These isolates displayed a >50-fold range of in vitro sensitivity to a sterol demethylation inhibitor (DMI) fungicide, propiconazole, making them ideal for investigations of genetic mechanisms of reduced DMI sensitivity. The CYP51 gene homolog in S. homoeocarpa (ShCYP51B), encoding the enzyme target of DMIs, is likely a minor genetic factor for reduced propiconazole sensitivity, since there were no differences in constitutive relative expression (RE) values and only 2-fold-higher induced RE values for insensitive than for sensitive isolate groups. Next, we mined RNA-Seq transcriptome data for additional genetic factors and found evidence for the overexpression of a homolog of Botrytis cinerea atrD (BcatrD), ShatrD, a known efflux transporter of DMI fungicides. The ShatrD gene showed much higher constitutive and induced RE values for insensitive isolates. Several polymorphisms were found upstream of ShatrD but were not definitively linked to overexpression. The screening of constitutive RE values of ShCYP51B and ShatrD in isolates from two golf courses that exhibited practical field resistance to propiconazole uncovered evidence for significant population-specific overexpression of both genes. However, linear regression demonstrated that the RE of ShatrD displays a more significant relationship with propiconazole sensitivity than that of ShCYP51B. In summary, our results suggest that efflux is a major determinant of the reduced DMI sensitivity of S. homoeocarpa genotypes in New England, which may have implications for the emergence of practical field resistance in this important turfgrass pathogen. PMID:22798361

Hulvey, Jon; Popko, James T; Sang, Hyunkyu; Berg, Andrew; Jung, Geunhwa

2012-09-01

131

Isolation and Characterization of Methanothermobacter crinale sp. nov., a Novel Hydrogenotrophic Methanogen from the Shengli Oil Field?†  

PubMed Central

Syntrophic acetate oxidation coupled with hydrogenotrophic methanogenesis is an alternative methanogenic pathway in certain thermophilic anaerobic environments such as high-temperature oil reservoirs and thermophilic biogas reactors. In these environments, the dominant thermophilic methanogens were generally related to uncultured organisms of the genus Methanothermobacter. Here we isolated two representative strains, Tm2T and HMD, from the oil sands and oil production water in the Shengli oil field in the People's Republic of China. The type strain, Tm2T, was nonmotile and stained Gram positive. The cells were straight to slightly curved rods (0.3 ?m in width and 2.2 to 5.9 ?m in length), but some of them possessed a coccal shape connecting with the rods at the ends. Strain Tm2T grew with H2-CO2, but acetate is required. Optimum growth of strain Tm2T occurred in the presence of 0.025 g/liter NaCl at pH 6.9 and a temperature of 65°C. The G+C content of the genomic DNA was 40.1 mol% ± 1.3 mol% (by the thermal denaturation method) or 41.1 mol% (by high-performance liquid chromatography). Analysis of the 16S rRNA gene sequence indicated that Tm2T was most closely related to Methanothermobacter thermautotrophicus ?HT and Methanothermobacter wolfeii VKM B-1829T (both with a sequence similarity of 96.4%). Based on these phenotypic and phylogenic characteristics, a novel species was proposed and named Methanothermobacter crinale sp. nov. The type strain is Tm2T (ACCC 00699T = JCM 17393T). PMID:21705537

Cheng, Lei; Dai, Lirong; Li, Xia; Zhang, Hui; Lu, Yahai

2011-01-01

132

Realistic modeling of entorhinal cortex field potentials and interpretation of epileptic activity in the guinea pig isolated brain preparation  

PubMed Central

Mechanisms underlying epileptic activities recorded from entorhinal cortex (EC) were studied through a computational model based on review of cytoarchitectonic and neurobiological data about this structure. The purpose of this study is to describe and use this model to interpret epileptiform discharge patterns recorded in an experimental model of ictogenesis (guinea-pig isolated brain perfused with bicuculline). A macroscopic modeling approach representing synaptic interactions between cells subpopulations in the EC was chosen for its adequacy to mimic field potentials reflecting overall dynamics rising from interconnected cells populations. Therefore, intrinsic properties of neurons were not included in the modeling design. Model parameters were adjusted from an identification procedure based on quantitative comparison between real and simulated signals. For both EC deep and superficial layers, results show that the model generates very realistic signals regarding temporal dynamics, spectral features and cross-correlation values. These simulations allowed us to infer information about the evolution of synaptic transmission between principal cell and interneuronal populations and about connectivity between deep and superficial layers during the transition from background to ictal activity. In the model, this transition was obtained for increased excitation in deep versus superficial layers. Transitions between epileptiform activities (interictal spikes, fast onset activity (25Hz), ictal bursting activity) were explained by changes of parameters mainly related to GABAergic interactions. Notably, the model predicted an important role of GABAa,fast and GABAb receptor-mediated inhibition in the generation of ictal fast onset and burst activities, respectively. These findings are discussed with respect to experimental data. PMID:16598061

Labyt, Etienne; Uva, Laura; De Curtis, Marco; Wendling, Fabrice

2006-01-01

133

Polyclonal infections due to Mycobacterium avium complex in patients with AIDS detected by pulsed-field gel electrophoresis of sequential clinical isolates.  

PubMed Central

Invasive infection with organisms of the Mycobacterium avium complex (MAC) is common among patients with advanced human immunodeficiency virus infection. In previous studies, we analyzed multiple individual colonies of MAC isolated from specimens obtained at the same time and observed that 14 to 20% of patients are simultaneously infected with more than one strain. In this study, we examined sequential isolates from 12 patients with AIDS who had two or more MAC isolates available from clinical specimens collected more than 1 week apart; the intervals between the first and last specimens ranged from 8 to 192 (median, 46) days. For each isolate, restriction digests of genomic DNA were analyzed by pulsed-field gel electrophoresis; DNA was prepared by using a protocol, described here in detail, which had been optimized for conditions of bacterial growth and lysis. The pulsed-field gel electrophoresis analysis identified four patients (33%) infected with two different MAC strains. Both M. avium and M. intracellulare were cultured from blood specimens from two patients. In each of the four patients, the second strain was identified from a culture taken within 14 days of the initial study isolate, and in three of these patients, the first strain was detected again in a subsequent culture. These observations suggest that the presence of two different strains among isolates from sequential cultures may reflect ongoing polyclonal infection. We conclude that polyclonal infection with MAC is common among patients with AIDS. The identification of such infections may be critical in the development of effective treatments. Images PMID:7929773

Slutsky, A M; Arbeit, R D; Barber, T W; Rich, J; von Reyn, C F; Pieciak, W; Barlow, M A; Maslow, J N

1994-01-01

134

Repression of Flagella Is a Common Trait in Field Isolates of Salmonella enterica Serovar Dublin and Is Associated with Invasive Human Infections  

PubMed Central

The nontyphoidal Salmonella enterica serovar Dublin is adapted to cattle but infrequently infects humans, very often resulting in invasive infections with high levels of morbidity and mortality. A Salmonella-induced intestinal acute inflammatory response is postulated as a mechanism to prevent bacterial dissemination to systemic sites. In S. enterica serovar Typhimurium, flagella contribute to this response by providing motility and FliC-mediated activation of pattern recognition receptors. In this study, we found 4 Salmonella enterica isolates, with the antigenic formula 9,12:?:?, that, based on fliC sequence and multilocus sequence type (MLST) analyses, are aflagellate S. Dublin isolates. Interestingly, all were obtained from human bloodstream infections. Thus, we investigated the potential role of flagella in the unusual invasiveness exhibited by S. Dublin in humans by analyzing flagellation and proinflammatory properties of a collection of 10 S. Dublin human clinical isolates. We found that 4 of 7 blood isolates were aflagellate due to significantly reduced levels of fliC expression, whereas all 3 isolates from other sources were flagellated. Lack of flagella correlated with a reduced ability of triggering interleukin-8 (IL-8) and CCL20 chemokine expression in human intestinal Caco-2 cells and with reduced early inflammation in the ceca of streptomycin-pretreated C57/BL6 mice. These results indicate that flagella contribute to the host intestinal inflammatory response to Salmonella serovar Dublin and suggest that their absence may contribute to its systemic dissemination through dampening of the gut immune response. Analysis of FliC production in a collection of cattle isolates indicated that the aflagellate phenotype is widely distributed in field isolates of S. Dublin. PMID:24421045

Sasias, Sebastian; Martinez, Araci; Betancor, Laura; Estevez, Veronica; Scavone, Paola; Bielli, Alejandro; Sirok, Alfredo; Chabalgoity, Jose Alejandro

2014-01-01

135

Field Induced Evolution of Regular and Random 2D Domain Structures and Shape of Isolated Domains in LiNbO3 and LiTaO3  

Microsoft Academic Search

The shapes of isolated domains produced by application of the uniform external electric field in different experimental conditions were investigated experimentally in single crystalline lithium niobate LiNbO3 and lithium tantalate LiTaO3. The study of the domain kinetics by computer simulation and experimentally by polarization reversal of the model structure using two-dimensional regular electrode pattern confirms applicability of the kinetic approach

A. I. Lobov; V. Ya. Shur; I. S. Baturin; E. I. Shishkin; D. K. Kuznetsov; A. G. Shur; M. A. Dolbilov; K. Gallo

2006-01-01

136

Pulsed-Field Gel Electrophoresis Typing of Oxacillin-Resistant Staphylococcus aureus Isolates from the United States: Establishing a National Database  

Microsoft Academic Search

Received 2 June 2003\\/Returned for modification 10 July 2003\\/Accepted 22 August 2003 Oxacillin-resistant Staphylococcus aureus (ORSA) is a virulent pathogen responsible for both health care- associated and community onset disease. We used SmaI-digested genomic DNA separated by pulsed-field gel electrophoresis (PFGE) to characterize 957 S. aureus isolates and establish a database of PFGE patterns. In addition to PFGE patterns of

Linda K. McDougal; Christine D. Steward; George E. Killgore; Jasmine M. Chaitram; Sigrid K. McAllister; Fred C. Tenover

2003-01-01

137

Stability and fitness of pyraclostrobin- and boscalid-resistant phenotypes in field isolates of Botrytis cinerea from apple.  

PubMed

Phenotype stability, fitness, and competitive ability of pyraclostrobin- and boscalid-resistant isolates of Botrytis cinerea from apple were investigated. Stability of resistance was determined after consecutive transfers on potato dextrose agar (PDA) or being cycled on apple fruit. In vitro fitness components mycelial growth, osmotic sensitivity, conidial germination, and sporulation were evaluated on agar media. Pathogenicity, virulence and sporulation on apple fruit were evaluated at both 20 and 0°C. Competition between fungicide-resistant and -sensitive isolates on apple fruit also was evaluated. Resistance to the two fungicides was retained at levels similar to that of the initial generation after 20 and 10 transfers on PDA and five and three disease cycles on apple fruit at 20 and 0°C, respectively. Great variability in individual fitness components tested was observed among isolates within the same phenotype groups either sensitive or resistant to the fungicides but, when compared as phenotype groups, there were no significant differences in the mean values of these fitness components between resistant and sensitive phenotypes except that the phenotype resistant only to boscalid produced fewer conidia in vitro than sensitive isolates. Resistant isolates were as pathogenic and virulent on apple fruit as sensitive isolates. There was no significant correlation between the values of individual fitness components tested and the level of resistance to pyraclostrobin or boscalid, except that virulence at 20°C positively correlated with the level of resistance to the two fungicides. The final frequency of pyraclostrobin-resistant individuals in the populations was significantly decreased compared with the initial generation and no boscalid-resistant individuals were detected after four disease cycles on apple fruit inoculated with a pair mixture of a dual-sensitive isolate and one isolate each of the three phenotypes resistant to pyraclostrobin, boscalid, or both. The results suggest that resistance of B. cinerea to pyraclostrobin and boscalid was stable in the absence of the fungicides and that resistance to the two fungicides did not significantly impair individual fitness components tested. However, both pyraclostrobin- and boscalid-resistant isolates exhibited competitive disadvantage over the dual-sensitive isolate on apple fruit. PMID:21692646

Kim, Y K; Xiao, C L

2011-11-01

138

A New Approach to Isolating External Magnetic Field Components in Spacecraft Measurements of the Earth's Magnetic Field Using Global Positioning System observables  

NASA Technical Reports Server (NTRS)

We review the problem of separating components of the magnetic field arising from sources in the Earth's core and lithosphere, from those contributions arising external to the Earth, namely ionospheric and magnetospheric fields, in spacecraft measurements of the Earth's magnetic field.

Raymond, C.; Hajj, G.

1994-01-01

139

Application of Pulsed-Field Gel Electrophoresis and Binary Typing as Tools in Veterinary Clinical Microbiology and Molecular Epidemiologic Analysis of Bovine and Human Staphylococcus aureus Isolates  

PubMed Central

Thirty-eight bovine mammary Staphylococcus aureus isolates from diverse clinical, temporal, and geographical origins were genotyped by pulsed-field gel electrophoresis (PFGE) after SmaI digestion of prokaryotic DNA and by means of binary typing using 15 strain-specific DNA probes. Seven pulsed-field types and four subtypes were identified, as were 16 binary types. Concordant delineation of genetic relatedness was documented by both techniques, yet based on practical and epidemiological considerations, binary typing was the preferable method. Genotypes of bovine isolates were compared to 55 previously characterized human S. aureus isolates through cluster analysis of binary types. Genetic clusters containing strains of both human and bovine origin were found, but bacterial genotypes were predominantly associated with a single host species. Binary typing proved an excellent tool for comparison of S. aureus strains, including methicillin-resistant S. aureus, derived from different host species and from different databases. For 28 bovine S. aureus isolates, detailed clinical observations in vivo were compared to strain typing results in vitro. Associations were found between distinct genotypes and severity of disease, suggesting strain-specific bacterial virulence. Circumstantial evidence furthermore supports strain-specific routes of bacterial dissemination. We conclude that PFGE and binary typing can be successfully applied for genetic analysis of S. aureus isolates from bovine mammary secretions. Binary typing in particular is a robust and simple method and promises to become a powerful tool for strain characterization, for resolution of clonal relationships of bacteria within and between host species, and for identification of sources and transmission routes of bovine S. aureus. PMID:10790124

Zadoks, Ruth; van Leeuwen, Willem; Barkema, Herman; Sampimon, Otlis; Verbrugh, Henri; Schukken, Ynte Hein; van Belkum, Alex

2000-01-01

140

Variation in permissiveness for broad-host-range plasmids among genetically indistinguishable isolates of Dickeya sp. from a small field plot.  

PubMed

Phytopathogenic populations need genetic flexibility to adapt to continually improving plant defences. The gene pool transferred by broad-host-range plasmids provides genetic variation for the population. However, a population has to balance this benefit with the risk of acquiring deleterious foreign DNA. This could be achieved by modulating the ratio of individuals with high or low permissiveness to broad-host-range plasmids. We investigated whether plasmid uptake varied among genetically indistinguishable isolates of Dickeya sp. from a 400 m(2) field plot. The transfer frequencies of broad-host-range IncP-1 plasmids from Escherichia coli to Dickeya differed significantly among isolates. The transfer frequencies for plasmids pTH10 and pB10 of the divergent alpha- and beta-subgroups of IncP-1, respectively, correlated well. Strains that differed in permissiveness for these plasmids by orders of magnitude were not distinguishable by other phenotypic traits analysed, by genomic fingerprints or hrpN gene sequences. Such strains were isolated in close vicinity and from different plots of the field, indicating a reasonably fast genetic mechanism of switching between low and high permissiveness. PMID:20455941

Heuer, Holger; Ebers, Jonas; Weinert, Nicole; Smalla, Kornelia

2010-07-01

141

Pulsed-field gel electrophoresis profile homogeneity of Mycobacterium avium subsp. paratuberculosis isolates from cattle and heterogeneity of those from sheep and goats  

PubMed Central

Background Mycobacterium avium subsp. paratuberculosis (Map) causes paratuberculosis in animals and is suspected of causing Crohn's Disease in humans. Characterization of strains led to classify paratuberculosis isolates in two main types, cattle type strains, found affecting all host species, and sheep type strains, reported affecting mainly sheep. In order to get a better understanding of the epidemiology of paratuberculosis a large set of Map isolates obtained from different species over the last 25 years have been characterized. Five-hundred and twenty isolates from different hosts (cattle, sheep, goats, bison, deer and wild boar) and origins had been cultured and typed by IS1311 restriction-endonuclease-analysis. Two-hundred and sixty-nine isolates were further characterized by pulsed-field gel electrophoresis (PFGE) using SnaBI and SpeI endonucleases. Differences in strain isolation upon various media conditions were also studied. Results All bovines, 4 and 26% of Spanish sheep and goats, respectively, and the deer and wild boar studied, carried IS1311-Cattle type strains. IS1311-Sheep type encompassed 96% and 74% of Spanish sheep and goats, and all three Portuguese sheep. Thirty-seven distinct multiplex PFGE profiles were found, giving 32 novel profiles. Profiles 2-1 and 1-1 accounted for the 85% of cattle isolates. Ten distinct profiles were detected in Spanish sheep, none of them with an incidence higher than 25%. Profile 16-11 (43%) and another three profiles were identified in Spanish caprine cultures. The hierarchical analysis, clustered all profiles found in cattle, "wild" hosts and some small ruminants within the same group. The other group included 11 profiles only found in Spanish sheep and goats, including Spanish pigmented profiles. Differences in growth requirements associated with isolate genotype were observed. Conclusion Cattle in Spain are infected with cattle type strains, while sheep and goats are mainly infected with sheep type strains. Although 7H9 broth based culture media seem to broadly cover the growth requirements of most Map strains, the use of various solid media is recommended to reduce any recovery biases. High genetic homogeneity of isolates from cattle, and heterogeneity of those from sheep and goats have been detected. PMID:17352818

Sevilla, Iker; Garrido, Joseba M; Geijo, Marivi; Juste, Ramon A

2007-01-01

142

Comparison of Two Multilocus Variable-Number Tandem-Repeat Methods and Pulsed-Field Gel Electrophoresis for Differentiating Highly Clonal Methicillin-Resistant Staphylococcus aureus Isolates?  

PubMed Central

In the United Kingdom, EMRSA-15 and EMRSA-16 account for the majority (?90%) of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infections. Currently, the standard typing technique, pulsed-field gel electrophoresis (PFGE), is laborious and insufficient for discriminating between closely related subtypes of EMRSA-15 and -16. The objective of the present study was to compare the usefulness of multilocus variable-number tandem-repeat fingerprinting (MLVF) and multilocus variable-number tandem-repeat analysis (MLVA) with PFGE for subtyping these highly clonal MRSA lineages. A panel of 85 MRSA isolates (41 EMRSA-15, 20 EMRSA-16, and 24 MRSA isolates with diverse PFGE patterns) was investigated. In addition, a further 29 EMRSA-15s with identical PFGE patterns from two geographically linked but epidemiologically distinct outbreaks and several sporadic cases were analyzed. PFGE, MLVF, and MLVA resolved 66 (Simpson's index of diversity [SID] = 0.984), 51 (SID = 0.95), and 42 (SID = 0.881) types, respectively, among the 85 MRSA isolates. MLVF was more discriminatory than MLVA for EMRSA-15 and -16 strains, but both methods had comparable discriminatory powers for distinguishing isolates in the group containing diverse PFGE types. MLVF was comparable to PFGE for resolving the EMRSA-15s but had a lower discriminatory power for the EMRSA-16s. MLVF and MLVA resolved the 29 isolates with identical PFGE patterns into seven and six subtypes, respectively. Importantly, both assays indicated that the two geographically related outbreaks were caused by distinct subtypes of EMRSA-15. Taken together, the data suggest that both methods are suitable for identifying and tracking specific subtypes of otherwise-indistinguishable MRSA. However, due to its greater discriminatory power, MLVF would be the most suitable alternative to PFGE for hospital outbreak investigations. PMID:20702668

Holmes, A.; Edwards, G. F.; Girvan, E. K.; Hannant, W.; Danial, J.; Fitzgerald, J. R.; Templeton, K. E.

2010-01-01

143

Comparison of multilocus sequence typing, pulsed-field gel electrophoresis, and antimicrobial susceptibility typing for characterization of Salmonella enterica serotype Newport isolates.  

PubMed

In the United States, multidrug-resistant phenotypes of Salmonella enterica serotype Newport (commonly referred to as MDR-AmpC) have emerged in animals and humans and have become a major public health problem. Although pulsed-field gel electrophoresis (PFGE) is the current "gold standard" typing method for Salmonella, multilocus sequence typing (MLST) may be more relevant to investigations exploring evolutionary and population biology relationships. In this study, 81 Salmonella enterica serotype Newport isolates from humans, food animals, and retail foods were examined for antimicrobial susceptibility and characterized using PFGE and MLST of seven genes, aroC, dnaN, hemD, hisD, purE, sucA, and thrA. Forty-nine percent of the isolates were resistant to nine or more of the tested antimicrobials. Salmonella isolates displayed resistance most often to sulfamethoxazole (57%), streptomycin (56%), tetracycline (56%), ampicillin (52%), and ceftiofur (49%) and, to a lesser extent, to kanamycin (19%), trimethoprim-sulfamethoxazole (17%), and gentamicin (11%). A total of 43 PFGE patterns were generated using XbaI, indicating a genetically diverse population. The largest PFGE cluster contained isolates from clinically ill swine, cattle, and humans. MLST resulted in 12 sequence types (STs), with one type encompassing 62% of the strains. Ten new sequence types and one novel allele type were identified. Furthermore, MLST typing showed that strains closely related by PFGE clustered in major STs, whereas more distantly related strains were separated into two clusters by PFGE. The results of this study demonstrated that the MLST scheme employed here clustered S. enterica serovar Newport isolates in distinct molecular populations, and strain discrimination was enhanced by combining PFGE, antimicrobial susceptibility, and MLST results. PMID:16825363

Harbottle, H; White, D G; McDermott, P F; Walker, R D; Zhao, S

2006-07-01

144

Serogrouping and pulsed-field gel electrophoresis analysis of Listeria monocytogenes isolates from cases of human infection in Hungary 2004–2012 molecular typing of Listeria monocytogenes in Hungary.  

PubMed

Eighty isolates of Listeria monocytogenes cultured from human infections in Hungary between 2004 and 2012 were serotyped by the PCR technique of Doumithet al. [9] and characterised by pulsed-field gel electrophoresis (PFGE). Most of the isolates belonged to two serogroups: 53 isolates (66.3%) to serovar group 4b,4d,4e and 21isolates (25.8%) to serogroup 1/2a,3a. Although many pulsotypes were identified a particular pulsotype proved highly excelling comprising of 31 isolates after digestion by both ApaI and AscI restriction enzymes. All strains from this pulsotype belonged toserovar group 4b,4d,4e. Interestingly 24% of isolates from invasive samples(cerebrospinal fluid, blood) belonged to two distinct pulsotypes in the less common serovar group 1/2a,3a. Several small clusters of cases caused by isolates with identical pulsotypes were identified. PMID:25046881

Pászti, Judit; Király, Józsefné; Füzi, Miklós

2014-03-01

145

Characterization of plant-growth promoting diazotrophic bacteria isolated from field grown Chinese cabbage under different fertilization conditions  

Microsoft Academic Search

Diazotrophic bacteria isolated from the rhizosphere of Chinese cabbage were assessed for other plant growth promoting characteristics\\u000a viz., production of IAA, ethylene, ACC deaminase, phosphate solubilization, and gnotobiotic root elongation. Their effect on inoculation\\u000a to Chinese cabbage was also observed under growth chamber conditions. A total of 19 strains that showed higher nitrogenase\\u000a activity identified by 16S rRNA gene sequence

Woo-Jong Yim; Selvaraj Poonguzhali; Munusamy Madhaiyan; Pitchai Palaniappan; M. A. Siddikee; Tongmin Sa

2009-01-01

146

[Ilha Grande Lazaretto: isolation, imprisonment, and surveillance in the fields of health care and politics (1884-1942)].  

PubMed

The Ilha Grande pest house, located on the coast of Rio de Janeiro state, was built in 1884 to control the spread of epidemics via Brazilian ports. Separated from the continent, the buildings that housed patients could be kept under constant surveillance. Isolation regimens differed in accordance with the class on which passengers had traveled. The complex was used at different times as a military prison and eventually deactivated. In 1942, it was restored and became the Cândido Mendes Penal Colony. PMID:18450303

dos Santos, Myrian Sepúlveda

2007-01-01

147

Sensitivity of rhabdomyosarcoma and guinea pig embryo cell cultures to field isolates of difficult-to-cultivate group A coxsackieviruses.  

PubMed Central

Forty-two difficult-to-cultivate group A coxsackieviruses (i.e., group A types other than A7, A9, and A16), collected primarily from throat swab specimens of patients suffering from fever, pharyngitis, lymphadenopathy, and cough during the 1986 enterovirus season, were isolated in less than 24-h-old suckling mice. Thirty-six moribund mice were sacrificed and autopsied, and then their brains and back musculature were inoculated into rhabdomyosarcoma (RD), guinea pig embryo (GPE), rhesus monkey kidney (RhMk) and human carcinoma of the larynx (HEp-2) cell cultures. Twelve of the 36 suckling mice isolates were adapted to grow in RD and GPE cells after two passes and have been identified in RD cells by type-specific antisera as group A coxsackievirus types A2, A4, and A8. Three passes in RhMk or HEp-2 cell cultures were insufficient to affect a discernible cytopathic effect. Coxsackievirus types A1, A19, and A22, unable to grow in any of the four cell cultures tested, were identified by virus neutralization in suckling mice. These data denote the efficacy of suckling mice for the isolation of difficult-to-cultivate group A coxsackieviruses. Images PMID:2842370

Lipson, S M; Walderman, R; Costello, P; Szabo, K

1988-01-01

148

Weed hosts of Verticillium dahliae in cotton fields in Turkey and characterization of V. dahliae isolates from weeds  

Microsoft Academic Search

A weed survey conducted in 2004 and 2005 in Aydin province of Turkey showed that Solanum nigrum, Xanthium strumarium, Amaranthus retroflexus, Portulaca oleracea, Sonchus oleraceus and Datura stramonium were the most prevalent weeds in the cotton fields exhibiting Verticillium wilt. Verticillium dahliae Kleb. was recovered from A. retroflexus and X. strumarium in those cotton fields. This is the first report

Ayhan Yildiz; M. Nedim Do?an; Özhan Boz; Seher Benlio?lu

2009-01-01

149

Salmonella Cerro isolated over the past twenty years from various sources in the US represent a single predominant Pulsed-Field Gel Electrophoresis type  

PubMed Central

Salmonella Cerro prevalence in US dairy cattle has increased significantly during the past decade. Comparison of 237 Salmonella isolates collected from various human and animal sources between 1986 and 2009 using pulsed- field gel electrophoresis, antimicrobial resistance typing, and spvA screening, showed very limited genetic diversity, indicating clonality of this serotype. Improved subtyping methods are clearly needed to analyze the potential emergence of this serotype. Our results thus emphasize the critical importance of population-based pathogen surveillance for the detection and characterization of potentially emerging pathogens, and caution to critically evaluate the adequacy of diagnostic tests for a given study population and diagnostic application. PMID:21349663

Hoelzer, K.; Cummings, K.J.; Wright, E.M.; Rodriguez-Rivera, L.D.; Roof, S.E.; Moreno Switt, A.I.; Dumas, N; Root, T.; Schoonmaker-Bopp, D.J.; Grohn, Y.T.; Siler, J.D.; Warnick, L.D.; Hancock, D.D.; Davis, M.A.; Wiedmann, M.

2011-01-01

150

Analysis of the Genome of a Korean Isolate of the Pieris rapae Granulovirus Enabled by Its Separation from Total Host Genomic DNA by Pulse-Field Electrophoresis  

PubMed Central

Background Most traditional genome sequencing projects involving viruses include the culture and purification of the virus particles. However, purification of virions may yield insufficient material for traditional sequencing. The electrophoretic method described here provides a strategy whereby the genomic DNA of the Korean isolate of Pieris rapae granulovirus (PiraGV-K) could be recovered in sufficient amounts for sequencing by purifying it directly from total host DNA by pulse-field gel electrophoresis (PFGE). Methodology/Principal Findings The total genomic DNA of infected P. rapae was embedded in agarose plugs, treated with restriction nuclease and methylase, and then PFGE was used to separate PiraGV-K DNA from the DNA of P. rapae, followed by mapping of fosmid clones of the purified viral DNA. The double-stranded circular genome of PiraGV-K was found to encode 120 open reading frames (ORFs), which covered 92% of the sequence. BLAST and ORF arrangement showed the presence of 78 homologs to other genes in the database. The mean overall amino acid identity of PiraGV-K ORFs was highest with the Chinese isolate of PiraGV (?99%), followed up with Choristoneura occidentalis ORFs at 58%. PiraGV-K ORFs were grouped, according to function, into 10 genes involved in transcription, 11 involved in replication, 25 structural protein genes, and 15 auxiliary genes. Genes for Chitinase (ORF 10) and cathepsin (ORF 11), involved in the liquefaction of the host, were found in the genome. Conclusions/Significance The recovery of PiraGV-K DNA genome by pulse-field electrophoretic separation from host genomic DNA had several advantages, compared with its isolation from particles harvested as virions or inclusions from the P. rapae host. We have sequenced and analyzed the 108,658 bp PiraGV-K genome purified by the electrophoretic method. The method appears to be generally applicable to the analysis of genomes of large viruses. PMID:24391907

Jo, Yong Hun; Patnaik, Bharat Bhusan; Kang, Se Won; Chae, Sung-Hwa; Oh, Seunghan; Kim, Dong Hyun; Noh, Mi Young; Seo, Gi Won; Jeong, Heon Cheon; Noh, Ju Young; Jeong, Ji Eun; Hwang, Hee Ju; Ko, Kisung; Han, Yeon Soo; Lee, Yong Seok

2013-01-01

151

Geometric Morphometrics of Nine Field Isolates of Aedes aegypti with Different Resistance Levels to Lambda-Cyhalothrin and Relative Fitness of One Artificially Selected for Resistance  

PubMed Central

Aedes aegypti, a mosquito closely associated with humans, is the principal vector of dengue virus which currently infects about 400 million people worldwide. Because there is no way to prevent infection, public health policies focus on vector control; but insecticide-resistance threatens them. However, most insecticide-resistant mosquito populations exhibit fitness costs in absence of insecticides, although these costs vary. Research on components of fitness that vary with insecticide-resistance can help to develop policies for effective integrated management and control. We investigated the relationships in wing size, wing shape, and natural resistance levels to lambda-cyhalothrin of nine field isolates. Also we chose one of these isolates to select in lab for resistance to the insecticide. The main life-traits parameters were assessed to investigate the possible fitness cost and its association with wing size and shape. We found that wing shape, more than wing size, was strongly correlated with resistance levels to lambda-cyhalothrin in field isolates, but founder effects of culture in the laboratory seem to change wing shape (and also wing size) more easily than artificial selection for resistance to that insecticide. Moreover, significant fitness costs were observed in response to insecticide-resistance as proved by the diminished fecundity and survival of females in the selected line and the reversion to susceptibility in 20 generations of the non-selected line. As a practical consequence, we think, mosquito control programs could benefit from this knowledge in implementing efficient strategies to prevent the evolution of resistance. In particular, the knowledge of reversion to susceptibility is important because it can help in planning better strategies of insecticide use to keep useful the few insecticide-molecules currently available. PMID:24801598

Jaramillo-O., Nicolas; Fonseca-Gonzalez, Idalyd; Chaverra-Rodriguez, Duverney

2014-01-01

152

Geometric morphometrics of nine field isolates of Aedes aegypti with different resistance levels to lambda-cyhalothrin and relative fitness of one artificially selected for resistance.  

PubMed

Aedes aegypti, a mosquito closely associated with humans, is the principal vector of dengue virus which currently infects about 400 million people worldwide. Because there is no way to prevent infection, public health policies focus on vector control; but insecticide-resistance threatens them. However, most insecticide-resistant mosquito populations exhibit fitness costs in absence of insecticides, although these costs vary. Research on components of fitness that vary with insecticide-resistance can help to develop policies for effective integrated management and control. We investigated the relationships in wing size, wing shape, and natural resistance levels to lambda-cyhalothrin of nine field isolates. Also we chose one of these isolates to select in lab for resistance to the insecticide. The main life-traits parameters were assessed to investigate the possible fitness cost and its association with wing size and shape. We found that wing shape, more than wing size, was strongly correlated with resistance levels to lambda-cyhalothrin in field isolates, but founder effects of culture in the laboratory seem to change wing shape (and also wing size) more easily than artificial selection for resistance to that insecticide. Moreover, significant fitness costs were observed in response to insecticide-resistance as proved by the diminished fecundity and survival of females in the selected line and the reversion to susceptibility in 20 generations of the non-selected line. As a practical consequence, we think, mosquito control programs could benefit from this knowledge in implementing efficient strategies to prevent the evolution of resistance. In particular, the knowledge of reversion to susceptibility is important because it can help in planning better strategies of insecticide use to keep useful the few insecticide-molecules currently available. PMID:24801598

Jaramillo-O, Nicolás; Fonseca-González, Idalyd; Chaverra-Rodríguez, Duverney

2014-01-01

153

Implementation of an indoxacarb susceptibility monitoring program using field-collected German cockroach isolates from the United States.  

PubMed

Indoxacarb, a sodium channel-blocking insecticide, has been in widespread use for German cockroach control in the United States since 2006. A two-tiered indoxacarb susceptibility monitoring strategy was previously developed as a first step toward determining indoxacarb susceptibility levels in German cockroach field populations. This strategy entails: (tier 1) testing field-collected populations in vial bioassays at two diagnostic concentrations; and (tier 2) testing populations at three diagnostic doses in oral (feeding) bioassays with treated bait matrix. In the current study the two-tiered technique was implemented to evaluate field (n = 14) and susceptible laboratory (n = 2) strains collected from 13 different U.S. locations. Our hypothesis was that at least some of the field-collected populations would display significant survivorship in both bioassays relative to susceptible laboratory populations. In agreement with this hypothesis, significantly reduced susceptibility was detected in 13 and 7 field strains with vial and feeding bioassays, respectively. In general, the lower number of strains displaying reduced susceptibility in feeding bioassays (seven strains) supports previous findings that indoxacarb is more toxic via ingestion. Although these findings suggest a reduced risk for resistance selection via feeding on indoxacarb-containing baits, they also suggest a need for proactive resistance management with respect to both spray and bait products. PMID:23786086

Gondhalekar, Ameya D; Scherer, Clay W; Saran, Raj K; Scharf, Michael E

2013-04-01

154

Are isolated wetlands isolated?  

USGS Publications Warehouse

While federal regulations during the past 10 years have treated isolated wetlands as unconnected to aquatic resources protected by the Clean Water Act, they provide critical ecosystem services to society that extend well beyond their wetland boundaries. The authors offer well-documented examples from the scientific literature on some of the ecosystem services provided by isolated wetlands to society and other ecosystems.

Smith, Loren M.; Euliss, Ned H.; Haukos, David A.

2011-01-01

155

Field application of the Numobag as a portable disposable isolation unit and for treating chemical, radiological or biologically induced wounds.  

SciTech Connect

Numotech Inc. has developed the Numobag{trademark}, a disposable, lightweight, wound healing device which produces Topical Hyperbaric Oxygen Therapy (THOT). The Numobag{trademark} is cost effective and has been clinically validated to heal large skin lesions rapidly and has proven to arrest wound advancement from several insidious forms of biological attack including dermal anthrax, small pox, necrotizing fasciitis etc. The Numobag{trademark} can treat mass casualties wounded by chemical/radiological burns or damaging biological exposures. The Numobag{trademark} can be a frontline tool as an isolation unit, reducing cross-contamination and infection of medical personnel. The heightened oxygen content kills organisms on the skin and in the wound, avoids expensive hospital trash disposal procedures, and helps the flesh heal. The Numobag{trademark} requires high purity oxygen. Numotech Inc. is teaming with Sandia National Laboratories and Spektr Conversion in Russia to develop a cost effective, portable, low power oxygen generator.

Miller, Keith A.; Felton, Robert; Vaughan, Courtenay Thomas

2005-04-01

156

Phylogenetic comparison of the S3 gene of United States prototype strains of bluetongue virus with that of field isolates from California.  

PubMed Central

To better define the molecular epidemiology of bluetongue virus (BTV) infection, the genetic characteristics and phylogenetic relationships of the S3 genes of the five U.S. prototype strains of BTV, the commercially available serotype 10 modified live virus vaccine, and 18 field isolates of BTV serotypes 10, 11, 13, and 17 obtained in California during 1980, 1981, 1989, and 1990 were determined. With the exception of the S3 gene of the U.S. prototype strain of BTV serotype 2 (BTV 2), these viruses had an overall sequence homology of between 95 and 100%. Phylogenetic analyses segregated the prototype U.S. BTV 2 strain to a unique branch (100% bootstrap value), whereas the rest of the viruses clustered in two main monophyletic groups that were not correlated with their serotype, year of isolation, or geographical origin. The lack of consistent association between S3 gene sequence and virus serotype likely is a consequence of reassortment of BTV gene segments during natural mixed infections of vertebrate and invertebrate hosts. The prototype strain of BTV 13, which is considered an introduction to the U.S. like BTV 2, presents an S3 gene which is highly homologous to those of some isolates of BTV 10 and especially to that of the vaccine strain. This finding strongly suggests that the U.S. prototype strain of BTV 13 is a natural reassortant. The different topologies of the phylogenetic trees of the L2 and S3 genes of the various viruses indicate that these two genome segments evolve independently. We conclude that the S3 gene segment of populations of BTV in California is formed by different consensus sequences which cocirculate and which cannot be grouped by serotype. PMID:8764098

de Mattos, C C; de Mattos, C A; MacLachlan, N J; Giavedoni, L D; Yilma, T; Osburn, B I

1996-01-01

157

Prevalence of Clostridium botulinum in Finnish Trout Farms: Pulsed-Field Gel Electrophoresis Typing Reveals Extensive Genetic Diversity among Type E Isolates  

PubMed Central

The distribution of Clostridium botulinum serotypes A, B, E, and F in Finnish trout farms was examined. A total of 333 samples were tested with a neurotoxin-specific PCR assay. C. botulinum type E was found in 68% of the farm sediment samples, in 15% of the fish intestinal samples, and in 5% of the fish skin samples. No other serotypes were found. The spore counts determined by the most-probable-number method were considerably higher for the sediments than for the fish intestines and skin; the average values were 2,020, 166, and 310 C. botulinum type E spores kg?1, respectively. The contamination rates in traditional freshwater ponds and marine net cages were high, but in concrete ponds equipped with sediment suction devices the contamination rates were significantly lower. Pulsed-field gel electrophoresis (PFGE) typing of 42 isolates obtained in this survey and 12 North American reference strains generated 28 pulsotypes upon visual inspection, suggesting that there was extensive genetic diversity and that the discriminatory power of PFGE typing in C. botulinum type E was high. A numerical analysis of SmaI-XmaI macrorestriction profiles confirmed these findings, as it divided the 54 isolates into 15 clusters at a similarity level of 76%. For this material, this level of similarity corresponded to a three-band difference in the macrorestriction profiles, which indicated that there is no genotypic proof of a close epidemiological relationship among the clusters. PMID:9797260

Hielm, Sebastian; Bjorkroth, Johanna; Hyytia, Eija; Korkeala, Hannu

1998-01-01

158

Permethrin resistance variation and susceptible reference line isolation in a field population of the mosquito, Culex quinquefasciatus (Diptera: Culicidae).  

PubMed

This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCq(G0) , and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCq(G0) strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCq(G8) mosquitoes were examined in the larvae of 3 strains (susceptible S-Lab, parental HAmCq(G0) and permethrin-selected highly resistant HAmCq(G8) ) and 8 HAmCq(G0) single-egg raft colonies, covering a range of levels of susceptibility/resistance to permethrin and exhibiting different variations in the expression of A and/or T alleles at the L-to-F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L-to-F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S-Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population: individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms-either elevated levels of P450 gene expression, or L-to-F mutations in the sodium channel, or both. PMID:24357606

Yang, Ting; Liu, Nannan

2014-10-01

159

Microbial Corrosion in Linepipe Steel Under the Influence of a Sulfate-Reducing Consortium Isolated from an Oil Field  

NASA Astrophysics Data System (ADS)

This work investigates microbiologically influenced corrosion of API 5L X52 linepipe steel by a sulfate-reducing bacteria (SRB) consortium. The SRB consortium used in this study was cultivated from a sour oil well in Louisiana, USA. 16S rRNA gene sequence analysis indicated that the mixed bacterial consortium contained three phylotypes: members of Proteobacteria ( Desulfomicrobium sp.), Firmicutes ( Clostridium sp.), and Bacteroidetes ( Anaerophaga sp.). The biofilm and the pits that developed with time were characterized using field emission scanning electron microscopy (FE-SEM). In addition, electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and open circuit potential (OCP) were used to analyze the corrosion behavior. Through circuit modeling, EIS results were used to interpret the physicoelectric interactions between the electrode, biofilm and solution interfaces. The results confirmed that extensive localized corrosion activity of SRB is due to a formed biofilm in conjunction with a porous iron sulfide layer on the metal surface. X-ray diffraction (XRD) revealed semiconductive corrosion products predominantly composed of a mixture of siderite (FeCO3), iron sulfide (Fe x S y ), and iron (III) oxide-hydroxide (FeOOH) constituents in the corrosion products for the system exposed to the SRB consortium.

AlAbbas, Faisal M.; Williamson, Charles; Bhola, Shaily M.; Spear, John R.; Olson, David L.; Mishra, Brajendra; Kakpovbia, Anthony E.

2013-11-01

160

Fields  

Microsoft Academic Search

The authors discuss the application of different statistical tests to the study of the spatial distribution of quasars. Applications to data sets of optically selected quasars lead to the detection of a clustering at a typical scale of 10 arcmin. Furthermore, the spatial distribution of quasars in a field around NGC 450 shows a deviation from randomness, towards clustering, at

E. Gosset; J. Surdej; J. P. Swings

1988-01-01

161

Atomic interferometer measurements of Berry and Aharonov-Anandan phases for isolated spins S>(1)/(2) nonlinearly coupled to external fields  

NASA Astrophysics Data System (ADS)

In a recent paper we have studied the peculiar features of the Berry and Aharonov-Anandan geometric phases for isolated spins S?1. We have assumed that they are submitted to a dipole and quadrupole coupling to external E and B fields with the mild restriction E·B=0. This implies discrete symmetries leading to remarkable simplifications of the geometry and algebra involved. The aim of the present work is to describe realistic proposals, within the realm of atomic physics, for the verification of some of our most significant theoretical predictions. There are several challenges to be overcome. For alkali-metal atoms, most commonly used in atomic interferometers, the only practical way to generate quadrupole coupling, with a strength comparable to the dipole one, is the ac Stark effect induced by a nearly resonant light beam. One then has to face the instability of the“dressed” atom hyperfine (hf) level, a candidate for our isolated spin. One deleterious effect is the apparition of an imaginary part in the quadrupole to dipole coupling strength ratio, ?. Fortunately we have found a simple way to get rid of I(?) by an appropriate detuning. We are left with an unstable isolated spin. This implies an upper bound to the quantum cycle duration Tc. In the case of the Berry’s phase, Tc has a lower bound due to the necessity of keeping the nonadiabatic corrections below a predefined level. We have found a compromise in the case of the F=2,m=0 Rb87 ground-state hf level. This is our candidate for the measurement of the somewhat “exotic” Berry’s phase acquired by the S=2,m=0 state at the end of a quantum cycle involving a rotation of ? of the E field—in practice, the linear polarization of the dressing beam —about the B field direction. We have found a way to implement, in a Ramsey-type interferometric measurement, the procedures aimed at controlling the nonadiabatic corrections, as described in detail in our previous theoretical paper. A numerical simulation of our experimental proposal shows that a 0.1% accurate determination of Berry’s phase, free of nonadiabatic corrections, can be achieved. Measurements could also be considered for cold Cr52 chromium atoms with S=3, where values of ??1 can be obtained with an instability smaller than in the Rb87 case, due to a more favorable spectroscopic structure. The F=1,m=1 hf level of the Rb87 ground state offers the opportunity to extend the measurement of Aharonov-Anandan’s phases beyond the case S=(1)/(2). We construct, using “light shift,” the Hamiltonian H?(t) generating a closed circuit in the density-matrix space which satisfies at any time the “parallel transport” condition, thus making the quantum cycle free from the adiabaticity condition. We also consider the case of half-integer spins (e.g., Hg201, Ba135, and Ba137), with their own specific features. We show how the difference of Berry’s phases for states S=(3)/(2) and S=(1)/(2), with m=(1)/(2), can be exploited to achieve a holonomic maximum entanglement of three qubits.

Bouchiat, Marie-Anne; Bouchiat, Claude

2011-05-01

162

Three species of Borrelia burgdorferi sensu lato (B. burgdorferi sensu stricto, B afzelii, and B. garinii) identified from cerebrospinal fluid isolates by pulsed-field gel electrophoresis and PCR.  

PubMed Central

A total of 36 European Borrelia burgdorferi sensu lato cerebrospinal fluid isolates (mainly from southern Germany) were analyzed by pulsed-field gel electrophoresis (PFGE) for large restriction fragment pattern (LRFP) and linear plasmid profiles. Analyzing this large panel of isolates, we detected all three species of B. burgdorferi sensu lato pathogenic for humans in cerebrospinal fluid from patients with Lyme neuroborreliosis by PFGE typing after MluI digestion: 21 B. garinii (58%), 10 B. afzelii (28%), and 4 B. burgdorferi sensu stricto (11%) strains as well as 1 isolate with bands characteristic of both B. afzelii and B. garinii. Species classification by PFGE typing was confirmed by 16S rRNA-specific PCR. Eighteen isolates (11 B. garinii, 6 B. afzelii, and 1 B. burgdorferi sensu stricto isolate) were further characterized by LRFP with four different restriction enzymes (ApaI, KspI, SmaI, and XhoI). All B. afzelii isolates showed identical patterns for each restriction enzyme group. Considerable heterogeneity was demonstrated within the B. garinii group. Subsequent analysis of plasmid profiles revealed only marginal differences for B. afzelii strains but different patterns for B. garinii isolates. In one B. afzelii strain we found a linear plasmid of about 110 kbp not described before. LRFP analysis by PFGE is a suitable tool for the molecular characterization of B. burgdorferi sensu lato strains and allows determination not only of the species but also of the subtypes within B. garinii. PMID:8727878

Busch, U; Hizo-Teufel, C; Boehmer, R; Fingerle, V; Nitschko, H; Wilske, B; Preac-Mursic, V

1996-01-01

163

Benchmark Database on Isolated Small Peptides Containing an Aromatic Side Chain: Comparison Between Wave Function and Density Functional Theory Methods and Empirical Force Field  

SciTech Connect

A detailed quantum chemical study on five peptides (WG, WGG, FGG, GGF and GFA) containing the residues phenylalanyl (F), glycyl (G), tryptophyl (W) and alanyl (A)—where F and W are of aromatic character—is presented. When investigating isolated small peptides, the dispersion interaction is the dominant attractive force in the peptide backbone–aromatic side chain intramolecular interaction. Consequently, an accurate theoretical study of these systems requires the use of a methodology covering properly the London dispersion forces. For this reason we have assessed the performance of the MP2, SCS-MP2, MP3, TPSS-D, PBE-D, M06-2X, BH&H, TPSS, B3LYP, tight-binding DFT-D methods and ff99 empirical force field compared to CCSD(T)/complete basis set (CBS) limit benchmark data. All the DFT techniques with a ‘-D’ symbol have been augmented by empirical dispersion energy while the M06-2X functional was parameterized to cover the London dispersion energy. For the systems here studied we have concluded that the use of the ff99 force field is not recommended mainly due to problems concerning the assignment of reliable atomic charges. Tight-binding DFT-D is efficient as a screening tool providing reliable geometries. Among the DFT functionals, the M06-2X and TPSS-D show the best performance what is explained by the fact that both procedures cover the dispersion energy. The B3LYP and TPSS functionals—not covering this energy—fail systematically. Both, electronic energies and geometries obtained by means of the wave-function theory methods compare satisfactorily with the CCSD(T)/CBS benchmark data.

Valdes, Haydee; Pluhackova, Kristyna; Pitonak, Michal; Rezac, Jan; Hobza, Pavel

2008-03-13

164

Listeria monocytogenes Biofilm-Associated Protein (BapL) May Contribute to Surface Attachment of L. monocytogenes but Is Absent from Many Field Isolates?  

PubMed Central

Listeria monocytogenes is a food-borne pathogen capable of adhering to a range of surfaces utilized within the food industry, including stainless steel. The factors required for the attachment of this ubiquitous organism to abiotic surfaces are still relatively unknown. In silico analysis of the L. monocytogenes EGD genome identified a putative cell wall-anchored protein (Lmo0435 [BapL]), which had similarity to proteins involved in biofilm formation by staphylococci. An insertion mutation was constructed in L. monocytogenes to determine the influence of this protein on attachment to abiotic surfaces. The results show that the protein may contribute to the surface adherence of strains that possess BapL, but it is not an essential requirement for all L. monocytogenes strains. Several BapL-negative field isolates demonstrated an ability to adhere to abiotic surfaces equivalent to that of BapL-positive strains. BapL is not required for the virulence of L. monocytogenes in mice. PMID:18515491

Jordan, Suzanne J.; Perni, Stefano; Glenn, Sarah; Fernandes, Isabel; Barbosa, Manuela; Sol, Manuela; Tenreiro, Rogerio P.; Chambel, Lelia; Barata, Belarmino; Zilhao, Isabel; Aldsworth, Timothy G.; Adriao, Andreia; Faleiro, M. Leonor; Shama, Gilbert; Andrew, Peter W.

2008-01-01

165

Overview of the data-acquisition system (including shielding, isolation and grounding) on the Beta II field-reversed plasma-gun experiment  

SciTech Connect

Computer-supported acquisition, analysis, and storage of mirror fusion experimental data requires the solution of several problems. The data must be gathered with a minimum amount of noise, and transients must be excluded from the computer so that it can function properly. On Beta II (which was an experiment to produce field-reversed plasma rings from a coaxial plasma gun) the diagnostic system was planned to provide the shielding and isolation necessary to solve these two problems. The Beta II system has been in operation for about two years and provides 300-channel capacity, CAMAC interfaced, to a Hewlett Packard 21MX computer. The system routinely handles signals ranging from 1 mV to 50 kV, with bandwidths from .05 Hz to 10 MHz. The data are captured by transient recorders during a shot, then transferred to the computer. The computer stores the data on disc for immediate processing and on tape for long-term storage. Processed data from any number of channels (usually 20 to 30) is plotted between shots for immediate review. The rest of the data is processed and plotted during off hours.

Bell, H.H. Jr.

1981-07-01

166

The rph1 Gene Is a Common Contributor to the Evolution of Phosphine Resistance in Independent Field Isolates of Rhyzopertha Dominica  

PubMed Central

Phosphine is the only economically viable fumigant for routine control of insect pests of stored food products, but its continued use is now threatened by the world-wide emergence of high-level resistance in key pest species. Phosphine has a unique mode of action relative to well-characterised contact pesticides. Similarly, the selective pressures that lead to resistance against field sprays differ dramatically from those encountered during fumigation. The consequences of these differences have not been investigated adequately. We determine the genetic basis of phosphine resistance in Rhyzopertha dominica strains collected from New South Wales and South Australia and compare this with resistance in a previously characterised strain from Queensland. The resistance levels range from 225 and 100 times the baseline response of a sensitive reference strain. Moreover, molecular and phenotypic data indicate that high-level resistance was derived independently in each of the three widely separated geographical regions. Despite the independent origins, resistance was due to two interacting genes in each instance. Furthermore, complementation analysis reveals that all three strains contain an incompletely recessive resistance allele of the autosomal rph1 resistance gene. This is particularly noteworthy as a resistance allele at rph1 was previously proposed to be a necessary first step in the evolution of high-level resistance. Despite the capacity of phosphine to disrupt a wide range of enzymes and biological processes, it is remarkable that the initial step in the selection of resistance is so similar in isolated outbreaks. PMID:22363668

Mau, Yosep S.; Collins, Patrick J.; Daglish, Gregory J.; Nayak, Manoj K.; Pavic, Hervoika; Ebert, Paul R.

2012-01-01

167

Biodegradation of alachlor in liquid and soil cultures under variable carbon and nitrogen sources by bacterial consortium isolated from corn field soil  

PubMed Central

Alachlor, an aniline herbicide widely used in corn production, is frequently detected in water resources. The main objectives of this research were focused on isolating bacterial consortium capable of alachlor biodegradation, assessing the effects of carbon and nitrogen sources on alachlor biodegradation and evaluating the feasibility of using bacterial consortium in soil culture. Kavar corn field soil with a long history of alachlor application in Fars province of Iran has been explored for their potential of alachlor biodegradation. The influence of different carbon compounds (glucose, sodium citrate, sucrose, starch and the combination of these compounds), the effect of nitrogen sources (ammonium nitrate and urea) and different pH (5.5-8.5) on alachlor removal efficiency by the bacterial consortium in liquid culture were investigated. After a multi-step enrichment program 100 days of acclimation, a culture with the high capability of alachlor degradation was obtained (63%). Glucose and sodium citrate had the highest alachlor reduction rate (85%). Alachlor reduction rate increased more rapidly by the addition of ammonium nitrate (94%) compare to urea. Based on the data obtained in the present study, pH of 7.5 is optimal for alachlor biodegradation. After 30 days of incubation, the percent of alachlor reduction were significantly enhanced in the inoculated soils (74%) as compared to uninoculated control soils (17.67%) at the soil moisture content of 25%. In conclusion, bioaugmentation of soil with bacterial consortium may enhance the rate of alachlor degradation in a polluted soil. PMID:23452801

2013-01-01

168

Virulence of Mexican isolates of entomopathogenic fungi (Hypocreales: Clavicipitaceae) upon Rhipicephalus=Boophilus microplus (Acari: Ixodidae) larvae and the efficacy of conidia formulations to reduce larval tick density under field conditions.  

PubMed

The first objective was laboratory evaluation of the virulence of 53 Mexican isolates of fungi against larvae of Rhipicephalus (Boophilus) microplus. Thirty-three isolates of Metarhizium anisopliae var. anisopliae (Metschnickoff) Sorokin (Hypocreales: Clavicipitaceae) and 20 isolates of Isaria (Paecilomyces) fumosorosea (fumosoroseus) (Wize) (Eurotiales: Trichomaceae) were tested on 7-day-old larvae under laboratory conditions. Larvae were immersed in a suspension containing 10(8)conidia/mL and the CL(50) values were estimated. Then, field tests were conducted to determine the efficacy of formulations of the isolate with the highest virulence. M. anisopliae (Ma 14 isolate) was formulated with four carriers: Tween, Celite, wheat bran, and Citroline (mineral oil) and applied on pasture beds of Cynodon plectostachyus (L.), at a dose of 2 x 10(9)CFU/m(2). In the first trial, M. anisopliae was applied on plots naturally infested with larvae; in the second trial, tick populations in the experimental plots were eliminated and then re-infested with 20,000 7-day-old larvae. In the laboratory, all M. anisopliae isolates infected larvae with a mortality range between 2 and 100%; also, 13 of 20 I. fumosorosea isolates caused mortality rates between 7 and 94%. In the first field trial, 14 days post-application, conidial formulations in Celite and wheat bran caused 67.8 and 94.2% population reduction, respectively. In the second trial, the Tween formulation caused the highest larval reduction, reaching up to 61% (28 days post-application). Wheat bran formulation caused 58.3% larval reduction (21 days post-application) and was one of the most effective. The carriers and emulsifiers have a large impact on the effectiveness of conidial formulations. PMID:20359827

Angel-Sahagún, C A; Lezama-Gutiérrez, R; Molina-Ochoa, J; Pescador-Rubio, A; Skoda, S R; Cruz-Vázquez, C; Lorenzoni, A G; Galindo-Velasco, E; Fragoso-Sánchez, H; Foster, J E

2010-06-24

169

Use of restriction fragment length polymorphisms resolved by pulsed-field gel electrophoresis for subspecies identification of mycobacteria in the Mycobacterium avium complex and for isolation of DNA probes.  

PubMed Central

Mycobacterial strains from the Mycobacterium avium complex were compared with each other and with Mycobacterium phlei isolates by restriction endonuclease digestion of chromosomal DNA with SspI and analysis by pulsed-field gel electrophoresis. Characteristic profiles were observed for known typed strains, and five groups were identified. Primary bovine isolates identified as Mycobacterium paratuberculosis by classical methods were shown to fall into both the M. paratuberculosis- and M. avium-like groups. M. paratuberculosis 18 was in the latter category. Two Mycobacterium intracellulare strains of different Schaefer serotypes had different digestion profiles. In addition, this system was exploited for the preparation of DNA probes by the isolation, digestion, and subcloning of DNA fragments separated by pulsed-field gel electrophoresis. Probe JC12 hybridized only to M. avium complex strains, but not to M. phlei, showing characteristic hybridization profiles for each of the groups previously identified by pulsed-field gel electrophoresis. The approach taken in the study lends itself to the comparative analysis of members of the M. avium complex and to the isolation and characterization of DNA probes with specificity for these mycobacteria. Images PMID:1352787

Coffin, J W; Condon, C; Compston, C A; Potter, K N; Lamontagne, L R; Shafiq, J; Kunimoto, D Y

1992-01-01

170

PHYSICAL REVIEW A 89, 023431 (2014) Generation of isolated sub-20-attosecond pulses from He atoms by two-color midinfrared laser fields  

E-print Network

28 February 2014) We propose an efficient method for the generation of ultrabroadband supercontinuum to the production of an ultrabroadband supercontinuum. As a result, an isolated 18-attosecond pulse can be generated for the efficient generation of an ultrabroadband supercontinuum and an isolated ultrashort attosecond laser pulse

Chu, Shih-I

171

Duganella sacchari sp. nov. and Duganella radicis sp. nov., two novel species isolated from rhizosphere of field-grown sugar cane.  

PubMed

Two strains, designated Sac-22(T) and Sac-41(T), were isolated from rhizosphere soil and rhizoplane of field-grown sugar cane clone Co86032. Comparative 16S rRNA gene sequence analysis showed a clear affiliation of these two bacteria with the class Betaproteobacteria, their closest relatives being Pseudoduganella violaceinigra and Duganella zoogloeoides with 16S rRNA gene sequence pairwise similarities of 96.4-97.2?% to the two novel strains. Strains Sac-22(T) and Sac-41(T) shared a 16S rRNA gene sequence similarity value of 97.6?%. Cells of the two strains were Gram-reaction-negative, aerobic, motile and rod-shaped. Ubiquinone (Q-8) was the respiratory quinone and the predominant polar lipids consisted of phosphatidylglycerol and phosphatidylethanolamine. The main cellular fatty acids were C16?:?0, C16?:?1?7c/iso-C15?:?0 2-OH, C17?:?0 cyclo, C10?:?0 3-OH and C12?:?0. The DNA G+C content of the genomic DNA was 56.4 mol% for strain Sac-22(T) and 54.9 mol% for strain Sac-41(T). Based on the results of 16S rRNA gene sequence analysis and physiological and biochemical characterization, that differentiated strains Sac-22(T) and Sac-41(T) from all recognized species of the genus Duganella, it was concluded that strains represent two novel species in the genus Duganella for which the names Duganella sacchari sp. nov. (type strain Sac-22(T)?=?KCTC 22381(T)?=?NCIMB 14475(T)) and Duganella radicis sp. nov. (type strain Sac-41(T)?=?KCTC 22382(T)?=?NCIMB 14476(T)) are proposed. PMID:22753524

Madhaiyan, M; Poonguzhali, S; Saravanan, V S; Hari, K; Lee, K-C; Lee, J-S

2013-03-01

172

The role of nanominerals and mineral nanoparticles in the transport of toxic trace metals: Field-flow fractionation and analytical TEM analyses after nanoparticle isolation and density separation  

NASA Astrophysics Data System (ADS)

Nanominerals and mineral nanoparticles from a mining-contaminated river system were examined to determine their potential to co-transport toxic trace metals. A recent large-scale dam removal project on the Clark Fork River in western Montana (USA) has released reservoir and upstream sediments contaminated with toxic trace metals (Pb, As, Cu and Zn), which had accumulated there as a consequence of more than a century and a half of mining activity proximal to the river's headwaters near the cities of Butte and Anaconda. To isolate the high-density nanoparticle fractions from riverbed and bank sediments, a density separation with sodium polytungstate (2.8 g/cm3) was employed prior to a standard nanoparticle extraction procedure. The stable, dispersed nanoparticulate fraction was then analyzed by analytical transmission electron microscopy (aTEM) and flow field-flow fractionation (FlFFF) coupled to both multi-angle laser light scattering (MALLS) and high-resolution, inductively coupled plasma mass spectrometry (HR-ICPMS). FlFFF analysis revealed a size distribution in the nano range and that the elution profiles of the trace metals matched most closely to that for Fe and Ti. aTEM confirmed these results as the majority of the Fe and Ti oxides analyzed were associated with one or more of the trace metals of interest. The main mineral phases hosting trace metals are goethite, ferrihydrite and brookite. This demonstrates that they are likely playing a significant role in dictating the transport and distribution of trace metals in this river system, which could affect the bioavailability and toxicity of these metals.

Plathe, Kelly L.; von der Kammer, Frank; Hassellöv, Martin; Moore, Johnnie N.; Murayama, Mitsuhiro; Hofmann, Thilo; Hochella, Michael F.

2013-02-01

173

Identification and Characterization of a New Erythromycin Biosynthetic Gene Cluster in Actinopolyspora erythraea YIM90600, a Novel Erythronolide-Producing Halophilic Actinomycete Isolated from Salt Field  

PubMed Central

Erythromycins (Ers) are clinically potent macrolide antibiotics in treating pathogenic bacterial infections. Microorganisms capable of producing Ers, represented by Saccharopolyspora erythraea, are mainly soil-dwelling actinomycetes. So far, Actinopolyspora erythraea YIM90600, a halophilic actinomycete isolated from Baicheng salt field, is the only known Er-producing extremophile. In this study, we have reported the draft genome sequence of Ac. erythraea YIM90600, genome mining of which has revealed a new Er biosynthetic gene cluster encoding several novel Er metabolites. This Er gene cluster shares high identity and similarity with the one of Sa. erythraea NRRL2338, except for two absent genes, eryBI and eryG. By correlating genotype and chemotype, the biosynthetic pathways of 3?-demethyl-erythromycin C, erythronolide H (EH) and erythronolide I have been proposed. The formation of EH is supposed to be sequentially biosynthesized via C-6/C-18 epoxidation and C-14 hydroxylation from 6-deoxyerythronolide B. Although an in vitro enzymatic activity assay has provided limited evidence for the involvement of the cytochrome P450 oxidase EryFAc (derived from Ac. erythraea YIM90600) in the catalysis of a two-step oxidation, resulting in an epoxy moiety, the attempt to construct an EH-producing Sa. erythraea mutant via gene complementation was not successful. Characterization of EryKAc (derived from Ac. erythraea YIM90600) in vitro has confirmed its unique role as a C-12 hydroxylase, rather than a C-14 hydroxylase of the erythronolide. Genomic characterization of the halophile Ac. erythraea YIM90600 will assist us to explore the great potential of extremophiles, and promote the understanding of EH formation, which will shed new insights into the biosynthesis of Er metabolites. PMID:25250723

Chen, Dandan; Feng, Junyin; Huang, Lei; Zhang, Qinglin; Wu, Jiequn; Zhu, Xiangcheng; Duan, Yanwen; Xu, Zhinan

2014-01-01

174

Terrimicrobium sacchariphilum gen. nov., sp. nov., an anaerobic bacterium of the class 'Spartobacteria' in the phylum Verrucomicrobia, isolated from a rice paddy field.  

PubMed

A strictly anaerobic, mesophilic, carbohydrate-fermenting bacterium, designated NM-5T, was isolated from a rice paddy field. Cells of strain NM-5(T) were Gram-stain-negative, non-motile, non-spore-forming, short rods (0.5-0.7 µm×0.6-1.2 µm). The strain grew optimally at 37 °C (growth range 20-40 °C) and pH 7.0 (pH 5.5-8.0). The strain could grow fermentatively on arabinose, xylose, fructose, galactose, glucose, ribose, mannose, cellobiose, lactose, maltose and sucrose. The main end-products of glucose fermentation were acetate and propionate. Organic acids, alcohols and amino acids were not utilized for growth. Yeast extract was not required but stimulated the growth. Nitrate, sulfate, thiosulfate, elemental sulfur, sulfite, and Fe (III) nitrilotriacetate were not used as terminal electron acceptors. The DNA G+C content was 46.3 mol%. The major cellular fatty acids were iso-C14:0, C18:0 and C16:0. 16S rRNA gene sequence analysis revealed that strain NM-5T belongs to the class 'Spartobacteria', subdivision 2 of the bacterial phylum Verrucomicrobia. Phylogenetically, the closest species was 'Chthoniobacter flavus' (89.6% similarity in 16S rRNA gene sequence). A novel genus and species, Terrimicrobium sacchariphilum gen. nov., sp. nov., is proposed. The type strain of the type species is NM-5T (=JCM 17479T=CGMCC 1.5168T). PMID:24535138

Qiu, Yan-Ling; Kuang, Xiao-zhu; Shi, Xiao-shuang; Yuan, Xian-zheng; Guo, Rong-bo

2014-05-01

175

Fitness and competitive ability of Botrytis cinerea field isolates with dual resistance to SDHI and QoI fungicides, associated with several sdhB and the cytb G143A mutations.  

PubMed

Respiration inhibitors such as the succinate dehydrogenase inhibitors (SDHIs) and the quinone outside inhibitors (QoIs) are fungicide classes with increasing relevance in gray mold control. However, recent studies have shown that dual resistance to both fungicide classes is a common trait in Botrytis cinerea populations from several hosts throughout the world. Resistance of B. cinerea to SDHIs is associated with several mutations in the sdhB, sdhC, and sdhD genes, while resistance to QoIs, in most cases, is associated with the G143A mutation in the cytb gene. The objective of the current study was to investigate the fitness and the competitive ability of B. cinerea field strains possessing one of the H272Y/R/L, N230I, or P225F sdhB substitutions and the G143A mutation of cytb. Fitness parameters measured were (i) mycelial growth and conidia germination in vitro, (ii) aggressiveness and sporulation capacity in vivo, (iii) sclerotia production in vitro and sclerotia viability under different storage conditions, and (iv) sensitivity to oxidative stress imposed by diquat treatments. The competitive ability of the resistant isolates was measured in the absence and presence of the SDHI fungicides boscalid and fluopyram selection pressure. The measurements of individual fitness components showed that the H272R/G143A isolates had the lower differences compared with the sensitive isolates. In contrast, the groups of H272Y/L/G143A, N230I/G143A, and P225F/G143A isolates showed reduced fitness values compared with the sensitive isolates. Isolates possessing only the cytb G143A substitution did not show any fitness cost. The competition experiments showed that, in the absence of fungicide selection pressure, after four disease cycles on apple fruit, the sensitive isolates dominated in the population in all the mixtures tested. In contrast, when the competition experiment was conducted under the selection pressure of boscalid, a gradual decrease in the frequency of sensitive isolates was observed, whereas the frequency of H272L and P225F isolates was increased. When the competition experiment was conducted in the presence of fluopyram, the sensitive isolates were eliminated even after the first disease cycle and the P225F mutants dominated in the population. Such results suggest that the sdhB mutations may have adverse effects on the mutants. The observed dominance of sensitive isolates in the competition experiments conducted in the absence of fungicides suggest that the application of SDHIs in alternation schemes may delay the selection or reduce the frequency of SDHI-resistant mutants. PMID:24168041

Veloukas, T; Kalogeropoulou, P; Markoglou, A N; Karaoglanidis, G S

2014-04-01

176

Polymorphic Amplified Typing Sequences and Pulsed-Field Gel Electrophoresis Yield Comparable Results in the Strain Typing of a Diverse Set of Bovine Escherichia coli O157:H7 Isolates  

PubMed Central

Polymorphic amplified typing sequences (PATS), a PCR-based Escherichia coli O157:H7 (O157) strain typing system, targets insertions-deletions and single nucleotide polymorphisms at XbaI and AvrII restriction enzyme sites, respectively, and the virulence genes (stx1, stx2, eae, hlyA) in the O157 genome. In this study, the ability of PATS to discriminate O157 isolates associated with cattle was evaluated. An in-depth comparison of 25 bovine O157 isolates, from different geographic locations across Northwest United States, showed that about 85% of these isolates shared the same dendogram clade by PATS and pulsed-field gel electrophoresis (PFGE), irrespective of the restriction enzyme sites targeted. The Pearson's correlation coefficient, r, calculated at about 0.4, 0.3, and 0.4 for XbaI-based, AvrII-based and combined-enzymes PATS and PFGE similarities, respectively, indicating that these profiles shared a good but not high correlation, an expected inference given that the two techniques discriminate differently. Isolates that grouped differently were better matched to their locations using PATS. Overall, PATS discriminated the bovine O157 isolates without interpretive biases or sophisticated analytical software, and effectively complemented while not duplicating PFGE. With its quick turnaround time, PATS has excellent potential as a convenient tool for early epidemiological or food safety investigations, enabling rapid notification/implementation of quarantine measures. PMID:23049559

Kudva, Indira T.; Davis, Margaret A.; Griffin, Robert W.; Garren, Jeonifer; Murray, Megan; John, Manohar; Hovde, Carolyn J.; Calderwood, Stephen B.

2012-01-01

177

Genetic heterogeneity of Indian field isolates of foot-and-mouth disease virus serotype O as revealed by partial sequencing of 1D gene  

Microsoft Academic Search

The sequence of 165 nucleotides at the 3? end of the 1D gene, determined from RT–PCR amplified cDNA fragments, of 25 type O strains isolated from different parts\\/regions of India during 1987–1995 and the vaccine strain (R2\\/75) currently in use in India were subjected to phylogenetic analysis. One isolate from the neighbouring country Nepal was also included in the study.

B. Pattnaik; R. Venkataramanan; C. Tosh; A. Sanyal; D. Hemadri; A. R. Samuel; N. J. Knowles; R. P. Kitching

1998-01-01

178

Comparison of Multiple-Locus Variable-Number Tandem-Repeat Analysis with Pulsed-Field Gel Electrophoresis, spa Typing, and Multilocus Sequence Typing for Clonal Characterization of Staphylococcus aureus Isolates  

Microsoft Academic Search

Multiple-locus variable-number tandem-repeat analysis (MLVA), a new PCR-based method of typing Staph- ylococcus aureus, was compared to pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing (MLST) on a group of 59 S. aureus (mostly methicillin-resistant) clinical isolates. The aim of the study was to establish possible criteria of clustering MLVA patterns and to check concordance levels between the

Natalia Malachowa; Artur Sabat; Marek Gniadkowski; Jolanta Krzyszton-Russjan; Joanna Empel; Jacek Miedzobrodzki; Klaudia Kosowska-Shick; Peter C. Appelbaum; Waleria Hryniewicz

2005-01-01

179

Evidence for high genetic diversity of NAD1 and COX1 mitochondrial haplotypes among triclabendazole resistant and susceptible populations and field isolates of Fasciola hepatica (liver fluke) in Australia.  

PubMed

In recent years, the global incidence of Fasciola hepatica (liver fluke) infections exhibiting resistance to triclabendazole (TCBZ) has increased, resulting in increased economic losses for livestock producers and threatening future control. The development of TCBZ resistance and the worldwide discovery of F. hepatica population diversity has emphasized the need to further understand the genetic structure of drug susceptible and resistant Fasciola populations within Australia. In this study, the genetic diversity of liver flukes was estimated by sequencing mitochondrial DNA (mtDNA) encoding the NAD1 (530 bp) and COX1 (420 bp) genes of 208 liver flukes (F. hepatica) collected from three populations: field isolates obtained from abattoirs from New South Wales (NSW) and Victoria (Vic); three TCBZ-resistant fluke populations from NSW and Victoria; and the well-established TCBZ-susceptible Sunny Corner laboratory isolate. Overall nucleotide diversity for all flukes analysed of 0.00516 and 0.00336 was estimated for the NAD1 and COX1 genes respectively. Eighteen distinct haplotypes were established for the NAD1 gene and six haplotypes for the COX1 gene, resulting in haplotype diversity levels of 0.832 and 0.482, respectively. One field isolate showed a similar low level of haplotype diversity as seen in the Sunny Corner laboratory isolate. Analysis of TCBZ-resistant infrapopulations from 3 individual cattle grazing one property revealed considerable sequence parasite diversity between cattle. Analysis of parasite TCBZ-resistant infrapopulations from sheep and cattle revealed haplotypes unique to each host, but no significant difference between parasite populations. Fst analysis of fluke populations revealed little differentiation between the resistant and field populations. This study has revealed a high level of diversity in field and drug resistant flukes in South-Eastern Australia. PMID:24360656

Elliott, T; Muller, A; Brockwell, Y; Murphy, N; Grillo, V; Toet, H M; Anderson, G; Sangster, N; Spithill, T W

2014-02-24

180

A second RGD motif in the 1D capsid protein of a SAT1 type foot-and-mouth disease virus field isolate is not essential for attachment to target cells  

Microsoft Academic Search

The amino acid sequence motif Arg-Gly-Asp (RGD), located in the surface-exposed ?G-?H loop of the 1D protein of different serotypes and subtypes of foot-and-mouth disease virus (FMDV), is highly conserved and participates in binding of FMDV to susceptible cells. Previous sequence analyses of the 1D-encoding region of a FMDV serotype SAT1 field isolate from Namibia (NAM\\/307\\/98) indicated the presence of

P. Storey; J. Theron; F. F. Maree; H. G. O’Neill

2007-01-01

181

Comparative Studies of Mutations in Animal Isolates and Experimental In Vitro and In Vivo-Selected Mutants of Salmonella spp. Suggest a Counterselection of Highly Fluoroquinolone-Resistant Strains in the Field  

Microsoft Academic Search

The occurrence of mutations in the genes coding for gyrase (gyrA and gyrB) and topoisomerase IV (parE and parC )o fSalmonella typhimurium experimental mutants selected in vitro and in vivo and of 138 nalidixic acid-resistant Salmonella field isolates was investigated. The sequencing of the quinolone resistance-determin- ing region of these genes in highly fluoroquinolone-resistant mutants (MICs of 4 to 16

ETIENNE GIRAUD; ANNE BRISABOIS; JEAN-LOUIS MARTEL; ELISABETH CHASLUS-DANCLA

1999-01-01

182

Azole-Resistant Aspergillus fumigatus Isolate with the TR34/L98H Mutation in Both a Fungicide-Sprayed Field and the Lung of a Hematopoietic Stem Cell Transplant Recipient with Invasive Aspergillosis  

PubMed Central

A French farmer developed invasive aspergillosis with azole-resistant Aspergillus fumigatus with the TR34/L98H mutation following a hematopoietic stem cell transplantation. He had worked in fungicide-sprayed fields where a non-genetically related A. fumigatus TR34/L98H isolate was collected. If azole resistance detection increases, voriconazole as first-line therapy might be questioned in agricultural areas. PMID:24554754

Rocchi, Steffi; Daguindau, Etienne; Grenouillet, Frederic; Deconinck, Eric; Bellanger, Anne-Pauline; Garcia-Hermoso, Dea; Bretagne, Stephane; Reboux, Gabriel

2014-01-01

183

Flavobacterium oryzae sp. nov., isolated from a flooded rice field, and emended descriptions of Flavobacterium flevense, Flavobacterium yonginense and Flavobacterium myungsuense.  

PubMed

A bacterial strain, designated Jyi-05(T), was isolated from a flooded rice field and characterized using a polyphasic taxonomic approach. Cells of strain Jyi-05(T) were Gram-stain-negative, strictly aerobic, bright-yellow-pigmented rods that were motile by gliding. Growth occurred at 10-30 °C (optimum 30 °C), at pH 6.5-7.5 (optimum pH 7.0) and with 0-2?% (w/v) NaCl (optimum 1?%, w/v, NaCl). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain Jyi-05(T) belonged to the genus Flavobacterium and was most closely related to Flavobacterium flevense DSM 1076(T) with sequence similarity of 97.6?%. Strain Jyi-05(T) contained iso-C15?:?0 (16.6?%), anteiso-C15?:?0 (10.8?%), summed feature 3 (C16?:?1?7c and/or C16?:?1?6c; 10.3?%), iso-C17?:?0 3-OH (9.2?%), C16?:?0 (7.3?%) and iso-C15?:?0 3-OH (7.2?%) as the predominant fatty acids. The major isoprenoid quinone was MK-6. The polar lipid profile consisted of phosphatidylethanolamine and several uncharacterized aminophospholipids and phospholipids. The major polyamine was homospermidine. The genomic DNA G+C content of strain Jyi-05(T) was 34.2 mol%. The DNA-DNA relatedness of strain Jyi-05(T) with respect to recognized species of the genus Flavobacterium was less than 70?%. On the basis of the phylogenetic inference and phenotypic data, strain Jyi-05(T) should be classified as a novel species, for which the name Flavobacterium oryzae sp. nov. is proposed. The type strain is Jyi-05(T) (?=?BCRC 80522(T)?=?LMG 27292(T)?=?KCTC 32240(T)). Emended descriptions of Flavobacterium flevense, Flavobacterium yonginense and Flavobacterium myungsuense are also presented. PMID:25106925

Chen, Wen-Ming; Chen, Jhen-Ci; Sheu, Shih-Yi

2014-11-01

184

Direct comparison of the histidine-rich protein-2 enzyme-linked immunosorbent assay (HRP-2 ELISA) and malaria SYBR green I fluorescence (MSF) drug sensitivity tests in Plasmodium falciparum reference clones and fresh ex vivo field isolates from Cambodia  

PubMed Central

Background Performance of the histidine-rich protein-2 enzyme-linked immunosorbent assay (HRP-2 ELISA) and malaria SYBR Green I fluorescence (MSF) drug sensitivity tests were directly compared using Plasmodium falciparum reference strains and fresh ex vivo isolates from Cambodia against a panel of standard anti-malarials. The objective was to determine which of these two common assays is more appropriate for studying drug susceptibility of “immediate ex vivo” (IEV) isolates, analysed without culture adaption, in a region of relatively low malaria transmission. Methods Using the HRP-2 and MSF methods, the 50% inhibitory concentration (IC50) values against a panel of malaria drugs were determined for P. falciparum reference clones (W2, D6, 3D7 and K1) and 41 IEV clinical isolates from an area of multidrug resistance in Cambodia. Comparison of the IC50 values from the two methods was made using Wilcoxon matched pair tests and Pearson’s correlation. The lower limit of parasitaemia detection for both methods was determined for reference clones and IEV isolates. Since human white blood cell (WBC) DNA in clinical samples is known to reduce MSF assay sensitivity, SYBR Green I fluorescence linearity of P. falciparum samples spiked with WBCs was evaluated to assess the relative degree to which MSF sensitivity is reduced in clinical samples. Results IC50 values correlated well between the HRP-2 and MSF methods when testing either P. falciparum reference clones or IEV isolates against 4-aminoquinolines (chloroquine, piperaquine and quinine) and the quinoline methanol mefloquine (Pearson r?=?0.85-0.99 for reference clones and 0.56-0.84 for IEV isolates), whereas a weaker IC50 value correlation between methods was noted when testing artemisinins against reference clones and lack of correlation when testing IEV isolates. The HRP-2 ELISA produced a higher overall success rate (90% for producing IC50 best-fit sigmoidal curves), relative to only a 40% success rate for the MSF assay, when evaluating ex vivo Cambodian isolates. Reduced sensitivity of the MSF assay is likely due to an interference of WBCs in clinical samples. Conclusions For clinical samples not depleted of WBCs, HRP-2 ELISA is superior to the MSF assay at evaluating fresh P. falciparum field isolates with low parasitaemia (<0.2%) generally observed in Southeast Asia. PMID:23849006

2013-01-01

185

Isolations of Jamestown Canyon virus (Bunyaviridae: Orthobunyavirus) from field-collected mosquitoes (Diptera: Culicidae) in Connecticut, USA: a ten-year analysis, 1997-2006.  

PubMed

Jamestown Canyon virus (JCV) (Bunyaviridae: Orthobunyavirus) is a mosquito-borne zoonosis belonging to the California serogroup. It has a wide geographic distribution, occurring throughout much of temperate North America. White-tailed deer, Odocoileus virginianus are the principal amplification hosts, and boreal Aedes and Ochlerotatus mosquitoes are the primary vectors. A 10-year study was undertaken to identify potential mosquito vectors in Connecticut, quantify seasonal prevalence rates of infection, and define the geographic distribution of JCV in the state as a function of land use and white-tailed deer populations, which have increased substantially over this period. Jamestown Canyon virus was isolated from 22 mosquito species. Five of them, Ochlerotatus canadensis, Oc. cantator, Anopheles punctipennis, Coquillettidia perturbans, and Oc. abserratus were incriminated as the most likely vectors, based on yearly isolation frequencies and the spatial geographic distribution of infected mosquitoes. Jamestown Canyon virus was isolated from Oc. canadensis more consistently and from a greater range of collection sites than any other species. Frequent virus isolations were also made from Aedes cinereus, Aedes vexans, and Oc. sticticus, and new North American isolation records were established for Anopheles walkeri, Culex restuans, Culiseta morsitans, Oc. sticticus, Oc. taeniorhynchus, and Psorophora ferox. Other species from which JCV was isolated included C. melanura, Oc. aurifer, Oc. communis, Oc. excrucians, Oc. provocans, Oc. sollicitans, Oc. stimulans, Oc. triseriatus, and Oc. trivittatus. Jamestown Canyon virus was widely distributed throughout Connecticut and found to consistently circulate in a diverse array of mosquito vectors. Infected mosquitoes were collected from June through September, and peak infection rates paralleled mosquito abundance from mid-June through mid-July. Infection rates in mosquitoes were consistent from year to year, and overall virus activity was directly related to local mosquito abundance. Infected mosquitoes were equally distributed throughout the state, irrespective of land use, and infection rates were not directly associated with the abundance of white-tailed deer, possibly because of their saturation throughout the region. PMID:18386967

Andreadis, Theodore G; Anderson, John F; Armstrong, Philip M; Main, Andrew J

2008-04-01

186

Reduction of sidewall defect induced leakage currents by the use of nitrided field oxides in silicon selective epitaxial growth isolation for advanced ultralarge scale integration  

Microsoft Academic Search

Defects in the near sidewall region in selective epitaxial growth of silicon have prevented its widespread use as a viable dielectric isolation technology. The main cause of these defects has been demonstrated to be thermal stress due to mismatch in the coefficient of thermal expansion between silicon and silicon dioxide. This article presents the detailed electrical characterization of these sidewall

R. Bashir; T. Su; J. M. Sherman; G. W. Neudeck; J. Denton; A. Obeidat

2000-01-01

187

Comparative analysis of Mycobacterium avium subsp. paratuberculosis isolates from cattle, sheep and goats by short sequence repeat and pulsed-field gel electrophoresis typing  

Microsoft Academic Search

BACKGROUND: Mycobacterium avium subsp. paratuberculosis (Map) causes the chronic enteritis called paratuberculosis mainly in cattle, sheep and goats. Evidences that point out an association between Map and Crohn's Disease in humans are increasing. Strain differentiation among Map isolates has proved to be difficult and has limited the study of the molecular epidemiology of paratuberculosis. In order to asses the usefulness

Iker Sevilla; Lingling Li; Alongkorn Amonsin; Joseba M Garrido; Maria V Geijo; Vivek Kapur; Ramón A Juste

2008-01-01

188

Isolated Malignant Melanoma Metastasis to the Pancreas  

PubMed Central

Summary: Malignant melanomas rarely develop isolated pancreatic metastases. We describe a unique patient who is still alive 22 years following an isolated pancreatic melanoma metastasis, and we review the sparse literature in the field.

Krag, Christen; Geertsen, Poul; Jakobsen, Linda P.

2013-01-01

189

Pulsed-Field Gel Electrophoresis (PFGE) Analysis of Temporally Matched Listeria monocytogenes Isolates from Human Clinical Cases, Foods, Ruminant Farms, and Urban and Natural Environments Reveals Source-Associated as Well as Widely Distributed PFGE Types? †  

PubMed Central

A total of 495 temporally and geographically matched Listeria monocytogenes isolates from human clinical cases, foods, ruminant farms, and urban and natural environments were used to investigate L. monocytogenes pulsed-field gel electrophoresis (PFGE) type diversity. Two-enzyme (AscI and ApaI) PFGE discriminated 310 PFGE types and exhibited higher overall discriminatory power (Simpson's index of discrimination [D] = 0.995) than either EcoRI ribotyping (D = 0.950) or AscI or ApaI single-enzyme PFGE (D = 0.992 for both). Seven PFGE types showed significant associations with specific sources, including one and four PFGE types, respectively, associated with human clinical cases and foods. Spatial analysis of 13 PFGE types occurring >5 times showed that two PFGE types were specific to a single processing facility each, where they appear to have persisted over time. Nine PFGE types were geographically widespread and occurred among isolates from multiple sources. For example, a PFGE type that matched isolates from listeriosis outbreaks in Los Angeles and Switzerland occurred among isolates from farms (n = 7), human clinical cases (n = 4), environmental sources (n = 3), and foods (n = 1). Our data indicate that (i) PFGE is highly discriminatory for the subtyping of L. monocytogenes, (ii) some L. monocytogenes PFGE types are associated with specific sources, and (iii) some L. monocytogenes PFGE types are widely distributed and appear to be stable and pandemic. Large PFGE type databases representing isolates from different sources are thus needed to appropriately interpret subtype data in epidemiological investigations and to identify common as well as source-specific PFGE types. PMID:17202278

Fugett, Eric B.; Schoonmaker-Bopp, Dianna; Dumas, Nellie B.; Corby, Joseph; Wiedmann, Martin

2007-01-01

190

Prevalence of Stx Phages in Environments of a Pig Farm and Lysogenic Infection of the Field E. coli O157 Isolates with a Recombinant Converting Phage  

Microsoft Academic Search

The prevalence and nature of Shiga toxin (Stx)-producing Escherichia coli (STEC) and Stx phage were investigated in 720 swine fecal samples randomly collected from a commercial breeding pig farm\\u000a in China over a 1-year surveillance period. Eight STEC O157 (1.1%), 33 STEC non-O157 (4.6%), and two stx-negative O157 (0.3%) isolates were identified. Fecal filtrates were screened directly for Stx phages

Yaxian Yan; Yibo Shi; Dongmei Cao; Xiangpeng Meng; Luming Xia; Jianhe Sun

2011-01-01

191

Isolated thallus-associated compounds from the macroalga Fucus vesiculosus mediate bacterial surface colonization in the field similar to that on the natural alga  

Microsoft Academic Search

This study investigated whether surface-associated compounds isolated from the macroalga Fucus vesiculosus had the potential to mediate microbial and\\/or macrobial epibiosis similar to that on the natural alga. To selectively yield thallus-associated compounds and avoid contamination by intracellular algal compounds, cell lysis was monitored by surface microscopy of algal cells and chemical profiling of algal surface extracts by coupled gas

Tim Lachnit; Martin Wahl; Tilmann Harder

2010-01-01

192

Social isolation.  

PubMed

Social species, by definition, form organizations that extend beyond the individual. These structures evolved hand in hand with behavioral, neural, hormonal, cellular, and genetic mechanisms to support them because the consequent social behaviors helped these organisms survive, reproduce, and care for offspring sufficiently long that they too reproduced. Social isolation represents a lens through which to investigate these behavioral, neural, hormonal, cellular, and genetic mechanisms. Evidence from human and nonhuman animal studies indicates that isolation heightens sensitivity to social threats (predator evasion) and motivates the renewal of social connections. The effects of perceived isolation in humans share much in common with the effects of experimental manipulations of isolation in nonhuman social species: increased tonic sympathetic tonus and HPA activation; and decreased inflammatory control, immunity, sleep salubrity, and expression of genes regulating glucocorticoid responses. Together, these effects contribute to higher rates of morbidity and mortality in older adults. PMID:21651565

Cacioppo, John T; Hawkley, Louise C; Norman, Greg J; Berntson, Gary G

2011-08-01

193

Social isolation  

PubMed Central

Social species, by definition, form organizations that extend beyond the individual. These structures evolved hand in hand with behavioral, neural, hormonal, cellular, and genetic mechanisms to support them because the consequent social behaviors helped these organisms survive, reproduce, and care for offspring sufficiently long that they too reproduced. Social isolation represents a lens through which to investigate these behavioral, neural, hormonal, cellular, and genetic mechanisms. Evidence from human and nonhuman animal studies indicates that isolation heightens sensitivity to social threats (predator evasion) and motivates the renewal of social connections. The effects of perceived isolation in humans share much in common with the effects of experimental manipulations of isolation in nonhuman social species: increased tonic sympathetic tonus and HPA activation, and decreased inflammatory control, immunity, sleep salubrity, and expression of genes regulating glucocorticoid responses. Together, these effects contribute to higher rates of morbidity and mortality in older adults. PMID:21651565

Cacioppo, John T.; Hawkley, Louise C.; Norman, Greg J.; Berntson, Gary G.

2011-01-01

194

Negotiating the radiologically isolated syndrome.  

PubMed

Multiple sclerosis, always challenging, hands down a particular gauntlet with the concept of the radiologically isolated syndrome. This article discusses what it is, recent developments in the field and how these patients should be managed. PMID:25291606

Cummings, A; Chataway, J

2014-10-01

195

Isolation, Pathogenicity and Safety of Curvularia eragrostidis Isolate QZ-2000 as a Bioherbicide Agent for Large Crabgrass (Digitaria sanguinalis)  

Microsoft Academic Search

A pathogen isolated from lesions on blighted leaves of crabgrass in three different locations of China was identified as Curvularia eragrostidis. Isolate QZ-2000 was the most virulent of six isolates tested. Experiments on morphology, pathogenicity, effect of environmental factors, and host-range of isolate QZ-2000 were conducted in the laboratory, greenhouse and field to assess the potential of this isolate as

Yunzhi Zhu; Sheng Qiang

2004-01-01

196

Multiple strain infections and high genotypic diversity among Mycobacterium avium subsp. paratuberculosis field isolates from diseased wild and domestic ruminant species in the eastern Alpine region of Austria.  

PubMed

Johne's disease, or paratuberculosis, is a chronic fatal ruminant gastroenteritis caused by Mycobacterium avium subspecies paratuberculosis (MAP) whose foodborne zoonotic potential and association with Crohn's disease are still under debate. The disease is widespread but its epidemiology and epizootiology remains elusive. Wildlife is suspected to play a major role. After a surge in MAP seroprevalence in Austrian cattle, paratuberculosis was declared a notifiable disease in Austria in 2006. At the same time a rise in MAP cases in wild ruminant populations in the Austrian province of Styria was reported. All five autochthonous ruminants were affected. Genetic analysis of isolates, yielded numerous genotypes (>15) and several multiple strain infections (15%) across host species. Identical MIRU-VNTR profiles were identified in different species and sampling locations. On the other hand varying MIRU-VNTR profiles were revealed at the same location and in conspecifics. Our data, taken together with earlier epidemiological studies on MAP and other mycobacteria, raised concerns about the organisms' ecology. Constraints regarding in vitro culture of this highly fastidious organism potentially bias our current understanding of its epidemiology. We suggest that MAP infections could be polyclonal and question the informative value of genotyping a single MAP colony derived from a single specimen for epidemiological analysis of MAP. PMID:24270014

Gerritsmann, H; Stalder, G L; Spergser, J; Hoelzl, F; Deutz, A; Kuebber-Heiss, A; Walzer, C; Smith, S

2014-01-01

197

Visible optical isolator using ZnSe  

NASA Technical Reports Server (NTRS)

A compact Faraday effect optical isolator was constructed for visible wavelengths and tested at 5145 A. The nonreciprocal element of the isolator was polycrystalline zinc selenide placed in the magnetic field of a permanent magnet. For 5145 A the isolator had a 2.06-dB insertion loss and a 25.5-dB isolation. Indices of refraction and Verdet constants were measured for zinc selenide in the wavelength region from 4700 to 6300 A.

Wunderlich, J. A.; Deshazer, L. G.

1977-01-01

198

Atomically thin nonreciprocal optical isolation.  

PubMed

Optical isolators will play a critical role in next-generation photonic circuits, but their on-chip integration requires miniaturization with suitable nonreciprocal photonic materials. Here, we theoretically demonstrate the thinnest possible and polarization-selective nonreciprocal isolation for circularly polarized waves by using graphene monolayer under an external magnetic field. The underlying mechanism is that graphene electron velocity can be largely different for the incident wave propagating in opposite directions at cyclotron frequency, making graphene highly conductive and reflective in one propagation direction while transparent in the opposite propagation direction under an external magnetic field. When some practical loss is introduced, nonreciprocal isolation with graphene monolayer still possesses good performance in a broad bandwidth. Our work shows the first study on the extreme limit of thickness for optical isolation and provides theoretical guidance in future practical applications. PMID:24569672

Lin, Xiao; Wang, Zuojia; Gao, Fei; Zhang, Baile; Chen, Hongsheng

2014-01-01

199

Isolating Triggered Star Formation  

SciTech Connect

Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to 'field' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than 'field' galaxies is primarily a selection effect. We use our simulations to devise a means to select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N= 2 halos) and to select a control sample of isolated galaxies (N= 1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M{sub B,j} {le} -19 and obtain the first clean measure of the typical fraction of galaxies affected by triggered star formation and the average elevation in the star formation rate. We find that 24% (30.5 %) of these L* and sub-L* galaxies in isolated 50 (30) h{sup -1} kpc pairs exhibit star formation that is boosted by a factor of {approx}> 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. Our orbit models suggest that 12% (16%) of 50 (30) h{sup -1} kpc close pairs that are isolated according to our definition have had a close ({le} 30 h{sup -1} kpc) pass within the last Gyr. Thus, the data are broadly consistent with a scenario in which most or all close passes of isolated pairs result in triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding the importance of triggered star formation in a cosmological context.

Barton, Elizabeth J.; Arnold, Jacob A.; /UC, Irvine; Zentner, Andrew R.; /KICP, Chicago /Chicago U., EFI; Bullock, James S.; /UC, Irvine; Wechsler, Risa H.; /KIPAC, Menlo

2007-09-12

200

Isolation of a wheat (Triticum aestivum L.) mutant in ABA 8?-hydroxylase gene: effect of reduced ABA catabolism on germination inhibition under field condition  

PubMed Central

Pre-harvest sprouting, the germination of mature seeds on the mother plant under moist condition, is a serious problem in cereals. To investigate the effect of reduced abscisic acid (ABA) catabolism on germination in hexaploid wheat (Triticum aestivum L.), we cloned the wheat ABA 8?-hydroxyase gene which was highly expressed during seed development (TaABA8?OH1) and screened for mutations that lead to reduced ABA catabolism. In a screen for natural variation, one insertion mutation in exon 5 of TaABA8?OH1 on the D genome (TaABA8?OH1-D) was identified in Japanese cultivars including ‘Tamaizumi’. However, a single mutation in TaABA8?OH1-D had no clear effect on germination inhibition in double haploid lines. In a screen for a mutation, one deletion mutant lacking the entire TaABA8?OH1 on the A genome (TaABA8?OH1-A), TM1833, was identified from gamma-ray irradiation lines of ‘Tamaizumi’. TM1833 (a double mutant in TaABA8?OH1-A and TaABA8?OH1-D) showed lower TaABA8?OH1 expression, higher ABA content in embryos during seed development under field condition and lower germination than those in ‘Tamaizumi’ (a single mutant in TaABA8?OH1-D). These results indicate that reduced ABA catabolism through mutations in TaABA8?OH1 may be effective in germination inhibition in field-grown wheat. PMID:23641187

Chono, Makiko; Matsunaka, Hitoshi; Seki, Masako; Fujita, Masaya; Kiribuchi-Otobe, Chikako; Oda, Shunsuke; Kojima, Hisayo; Kobayashi, Daisuke; Kawakami, Naoto

2013-01-01

201

Isolation of a wheat (Triticum aestivum L.) mutant in ABA 8'-hydroxylase gene: effect of reduced ABA catabolism on germination inhibition under field condition.  

PubMed

Pre-harvest sprouting, the germination of mature seeds on the mother plant under moist condition, is a serious problem in cereals. To investigate the effect of reduced abscisic acid (ABA) catabolism on germination in hexaploid wheat (Triticum aestivum L.), we cloned the wheat ABA 8'-hydroxyase gene which was highly expressed during seed development (TaABA8'OH1) and screened for mutations that lead to reduced ABA catabolism. In a screen for natural variation, one insertion mutation in exon 5 of TaABA8'OH1 on the D genome (TaABA8'OH1-D) was identified in Japanese cultivars including 'Tamaizumi'. However, a single mutation in TaABA8'OH1-D had no clear effect on germination inhibition in double haploid lines. In a screen for a mutation, one deletion mutant lacking the entire TaABA8'OH1 on the A genome (TaABA8'OH1-A), TM1833, was identified from gamma-ray irradiation lines of 'Tamaizumi'. TM1833 (a double mutant in TaABA8'OH1-A and TaABA8'OH1-D) showed lower TaABA8'OH1 expression, higher ABA content in embryos during seed development under field condition and lower germination than those in 'Tamaizumi' (a single mutant in TaABA8'OH1-D). These results indicate that reduced ABA catabolism through mutations in TaABA8'OH1 may be effective in germination inhibition in field-grown wheat. PMID:23641187

Chono, Makiko; Matsunaka, Hitoshi; Seki, Masako; Fujita, Masaya; Kiribuchi-Otobe, Chikako; Oda, Shunsuke; Kojima, Hisayo; Kobayashi, Daisuke; Kawakami, Naoto

2013-03-01

202

Isolated optical vortex knots  

NASA Astrophysics Data System (ADS)

Natural and artificially created light fields in three-dimensional space contain lines of zero intensity, known as optical vortices. Here, we describe a scheme to create optical beams with isolated optical vortex loops in the forms of knots and links using algebraic topology. The required complex fields with fibred knots and links are constructed from abstract functions with braided zeros and the knot function is then embedded in a propagating light beam. We apply a numerical optimization algorithm to increase the contrast in light intensity, enabling us to observe several optical vortex knots. These knotted nodal lines, as singularities of the wave's phase, determine the topology of the wave field in space, and should have analogues in other three-dimensional wave systems such as superfluids and Bose-Einstein condensates.

Dennis, Mark R.; King, Robert P.; Jack, Barry; O'Holleran, Kevin; Padgett, Miles J.

2010-02-01

203

Study of the Bioremediation of Atrazine under Variable Carbon and Nitrogen Sources by Mixed Bacterial Consortium Isolated from Corn Field Soil in Fars Province of Iran  

PubMed Central

Atrazine herbicide that is widely used in corn production is frequently detected in water resources. The main objectives of this research were focused on assessing the effects of carbon and nitrogen sources on atrazine biodegradation by mixed bacterial consortium and by evaluating the feasibility of using mixed bacterial consortium in soil culture. Shiraz corn field soil with a long history of atrazine application has been explored for their potential of atrazine biodegradation. The influence of different carbon compounds and the effect of nitrogen sources and a different pH (5.5–8.5) on atrazine removal efficiency by mixed bacterial consortium in liquid culture were investigated. Sodium citrate and sucrose had the highest atrazine biodegradation rate (87.22%) among different carbon sources. Atrazine biodegradation rate decreased more quickly by the addition of urea (26.76%) compared to ammonium nitrate. Based on the data obtained in this study, pH of 7.0 is optimum for atrazine biodegradation. After 30 days of incubation, the percent of atrazine reduction rates were significantly enhanced in the inoculated soils (60.5%) as compared to uninoculated control soils (12%) at the soil moisture content of 25%. In conclusion, bioaugmentation of soil with mixed bacterial consortium may enhance the rate of atrazine degradation in a highly polluted soil. PMID:23533452

Nasseri, Simin; Hashemi, Hassan

2013-01-01

204

Field and laboratory investigations of coring-induced damage in core recovered from Marker Bed 139 at the waste isolation pilot plant underground facility  

SciTech Connect

A combined laboratory and field investigation was carried out to determine the extent of coring-induced damage done to samples cored from Marker Bed 139 at the WIPP site. Coring-induced damage, if present, has the potential to significantly change the properties of the material used for laboratory testing relative to the in situ material properties, resulting in misleading conclusions. In particular, connected, crack-like damage could make the permeability of cored samples orders of magnitude greater than the in situ permeabilities. Our approach compared in situ velocity and resistivity measurements with laboratory measurements of the same properties. Differences between in situ and laboratory results could be attributed to differences in the porosity due to cracks. The question of the origin of the changes could not be answered directly from the results of the measurements. Pre-existing cracks, held closed by the in situ stress, could open when the core was cut free, or new cracks could be generated by coring-induced damage. We used core from closely spaced boreholes at three orientations (0{degree}, {plus_minus}45{degrees} relative to vertical) to address the origin of cracks. The absolute orientation of pre-existing cracks would be constant, independent of the borehole orientation. In contrast, cracks induced by coring were expected to show an orientation dependent on that of the source borehole.

Holcomb, D.J.; Zeuch, D.H.; Morin, K.; Hardy, R.; Tormey, T.V.

1995-09-01

205

Standardization and international multicenter validation of a PulseNet pulsed-field gel electrophoresis protocol for subtyping Shigella flexneri isolates.  

PubMed

Shigella flexneri is one of the agents most frequently linked to diarrheal illness in developing countries and often causes outbreaks in settings with poor hygiene or sanitary conditions. Travel is one of the means by which S. flexneri can be imported into developed countries, where this pathogen is not commonly seen. A robust and discriminatory subtyping method is needed for the surveillance of S. flexneri locally and regionally, and to aid in the detection and investigation of outbreaks. The PulseNet International network utilizes standardized pulsed-field gel electrophoresis (PFGE) protocols to carry out laboratory-based surveillance of foodborne pathogens in combination with epidemiologic data. A multicenter validation was carried out in nine PulseNet laboratories located in North and South America, Europe, and Asia, and it demonstrated that a new protocol is highly robust and reproducible for subtyping of S. flexneri. This protocol, already approved for PulseNet laboratories, applies NotI and XbaI as primary and secondary restriction enzymes, respectively, under electrophoresis conditions of initial switch time of 5 s to final switch time of 35 s, at 6 volts/cm. PMID:22506731

Pichel, Mariana; Brengi, Silvina P; Cooper, Kara L F; Ribot, Efrain M; Al-Busaidy, Suleiman; Araya, Pamela; Fernández, Jorge; Vaz, Tania Ibelli; Kam, Kai Man; Morcos, Myriam; Nielsen, Eva M; Nadon, Celine; Pimentel, Guillermo; Pérez-Gutiérrez, Enrique; Gerner-Smidt, Peter; Binsztein, Norma

2012-05-01

206

ISOLATION OF PIG ROTAVIRUS IN FRANCE IDENTIFICATION AND EXPERIMENTAL INFECTIONS  

E-print Network

ISOLATION OF PIG ROTAVIRUS IN FRANCE IDENTIFICATION AND EXPERIMENTAL INFECTIONS G. CORTHIER J piglets with field rotavirus isolates. Bacteria-free isolates were inoculated orally to 6 piglets (2 per%mmuno%gie 78850 Thiverval-Grignon, France Résumé ISOLEMENT DE ROTAVIRUS D'ORIGINE PORCINE EN FRANCE

Paris-Sud XI, Université de

207

Rhabdothermus arcticus gen. nov., sp. nov., a member of the family Thermaceae isolated from a hydrothermal vent chimney in the Soria Moria vent field on the Arctic Mid-Ocean Ridge.  

PubMed

A novel thermophilic member of the family Thermaceae, designated strain 2M70-1(T), was isolated from the wall of an active white smoker chimney collected in the Soria Moria vent field at 71 °N in the Norwegian-Greenland Sea. Cells of the strain were Gram-negative, non-motile rods. Growth was observed at 37-75 °C (optimum 65 °C), at pH 6-8 (optimum pH 7.3) and in 1-5?% (w/v) NaCl (optimum 2.5-3.5?%). The isolate was aerobic but could also grow anaerobically using nitrate or elemental sulfur as electron acceptors. The strain was obligately heterotrophic, growing on complex organic substrates like yeast extract, Casamino acids, tryptone and peptone. Pyruvate, acetate, butyrate, sucrose, rhamnose and maltodextrin were used as complementary substrates. The G+C content of the genomic DNA was 68 mol%. Cells possessed characteristic phospholipids and glycolipids. Major fatty acids constituted saturated and unsaturated iso-branched and saturated anteiso-branched forms. Menaquinone 8 was the sole respiratory lipoquinone. Phylogenetic analysis of 16S rRNA gene sequences placed the strain in the family Thermaceae in the phylum 'Deinococcus-Thermus', which is consistent with the chemotaxonomic data. On the basis of phenotypic and phylogenetic data, strain 2M70-1(T) (?=?JCM 15963(T) ?=?DSM 22268(T)) represents the type strain of a novel species of a novel genus, for which the name Rhabdothermus arcticus gen. nov., sp. nov. is proposed. PMID:20935086

Steinsbu, Bjørn O; Tindall, Brian J; Torsvik, Vigdis L; Thorseth, Ingunn H; Daae, Frida L; Pedersen, Rolf B

2011-09-01

208

Drop-on-Demand Single Cell Isolation and Total RNA Analysis  

E-print Network

Technologies that rapidly isolate viable single cells from heterogeneous solutions have significantly contributed to the field of medical genomics. Challenges remain both to enable efficient extraction, isolation and ...

Moon, Sangjun

209

Supersymmetric isolated horizons  

E-print Network

We construct a covariant phase space for rotating weakly isolated horizons in Einstein-Maxwell-Chern-Simons theory in all (odd) $D\\geq5$ dimensions. In particular, we show that horizons on the corresponding phase space satisfy the zeroth and first laws of black-hole mechanics. We show that the existence of a Killing spinor on an isolated horizon in four dimensions (when the Chern-Simons term is dropped) and in five dimensions requires that the induced (normal) connection on the horizon has to vanish, and this in turn implies that the surface gravity and rotation one-form are zero. This means that the gravitational component of the horizon angular momentum is zero, while the electromagnetic component (which is attributed to the bulk radiation field) is unconstrained. It follows that an isolated horizon is supersymmetric only if it is extremal and nonrotating. A remarkable property of these horizons is that the Killing spinor only has to exist on the horizon itself. It does not have to exist off the horizon. In addition, we find that the limit when the surface gravity of the horizon goes to zero provides a topological constraint. Specifically, the integral of the scalar curvature of the cross sections of the horizon has to be positive when the dominant energy condition is satisfied and the cosmological constant $\\Lambda$ is zero or positive, and in particular rules out the torus topology for supersymmetric isolated horizons (unless $\\Lambda<0$) if and only if the stress-energy tensor $T_{ab}$ is of the form such that $T_{ab}\\ell^{a}n^{b}=0$ for any two null vectors $\\ell$ and $n$ with normalization $\\ell_{a}n^{a}=-1$ on the horizon.

Tomas Liko; Ivan Booth

2007-12-19

210

Isolated sleep paralysis  

MedlinePLUS

Sleep paralysis - isolated; Parasomnia - Isolated sleep paralysis ... Episodes of isolated sleep paralysis last from a few seconds to 1 or 2 minutes in which the person is unable to move or speak. ...

211

Isolation and characterization of a heavy metal-resistant Burkholderia sp. from heavy metal-contaminated paddy field soil and its potential in promoting plant growth and heavy metal accumulation in metal-polluted soil  

Microsoft Academic Search

A heavy metal-resistant bacterial strain was isolated from heavy metal-contaminated soils and identified as Burkholderia sp. J62 based on the 16S rDNA gene sequence analysis. The heavy metal- and antibiotic resistance, heavy metal solubilization of the isolate were investigated. The isolate was also evaluated for promoting plant growth and Pb and Cd uptakes of the plants from heavy metal-contaminated soils

Chun-yu Jiang; Xia-fang Sheng; Meng Qian; Qing-ya Wang

2008-01-01

212

Isolated Northern Dunes  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

This VIS image was taken at 81 degrees North latitude during Northern spring. In this region, the dunes are isolated from each other. The dunes are just starting to emerge from the winter frost covering appearing dark with bright crests. These dunes are located on top of ice.

Image information: VIS instrument. Latitude 82.1, Longitude 191.3 East (168.7 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2005-01-01

213

Isolated neutron stars in the galaxy: from magnetars to antimagnetars  

SciTech Connect

Using the model with decaying magnetic fields it is possible to describe with one smooth (log-Gaussian) initial magnetic field distribution three types of isolated neutron stars: radiopulsar, magnetars, and cooling close-by compact objects. The same model is used here to make predictions for old accreting isolated neutron stars. It is shown that using the updated field distribution we predict a significant fraction of isolated neutron stars at the stage of accretion despite long subsonic propeller stage.

Boldin, P. A., E-mail: boldin.pavel@gmail.com [Moscow Engineering Physics Institute (State University) (Russian Federation); Popov, S. B., E-mail: polar@sai.msu.ru [Moscow State University, Sternberg Astronomical Institute (Russian Federation)

2012-07-15

214

Xylanibacter oryzae gen. nov., sp. nov., a novel strictly anaerobic, Gram-negative, xylanolytic bacterium isolated from rice-plant residue in flooded rice-field soil in Japan.  

PubMed

A strictly anaerobic, xylanolytic bacterium, strain KB3(T), isolated from rice-plant residue in flooded anoxic rice-field soil in Japan, was characterized phenotypically and phylogenetically. Cells were Gram-negative, non-motile, non-spore-forming, short to filamentous rods. Growth of the strain was remarkably stimulated by the addition of haemin to the medium. The novel strain utilized various sugars including xylan, xylose, pectin and carboxymethylcellulose and produced acetate, propionate and succinate with a small amount of malate. Propionate production was stimulated by the addition of a B-vitamin mixture or cobalamin to the medium. The novel strain was slightly acidophilic with an optimum pH 5.7-6.2 and the optimum growth temperature was 30 degrees C. Oxidase, catalase and nitrate-reducing activities were negative. Aesculin was hydrolysed. The major cellular fatty acids were anteiso-C(15 : 0) and iso-3-OH C(17 : 0). The major respiratory quinones were menaquinones MK-12(H(2)) and MK-13(H(2)). The genomic DNA G+C content was 43.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequence placed the strain in the phylum Bacteroidetes. The closest related species was Prevotella bivia with a 16S rRNA gene sequence similarity of 89.5 %. Prevotella albensis and Prevotella oulorum were the next closest recognized species with sequence similarities of 89.1 %. Based on a comprehensive examination of the differences in phylogenetic, ecological, physiological and chemotaxonomic characteristics of strain KB3(T) and those of related species, a novel genus and species, Xylanibacter oryzae gen. nov., sp. nov., is proposed to accommodate strain KB3(T). The type strain of the novel species is KB3(T) (=JCM 13648(T)=DSM 17970(T)). PMID:16957124

Ueki, Atsuko; Akasaka, Hiroshi; Suzuki, Daisuke; Hattori, Satoshi; Ueki, Katsuji

2006-09-01

215

Sequence Analysis of the 144-Kilobase Accessory Plasmid pSmeSM11a, Isolated from a Dominant Sinorhizobium meliloti Strain Identified during a Long-Term Field Release Experiment†  

PubMed Central

The genome of Sinorhizobium meliloti type strain Rm1021 consists of three replicons: the chromosome and two megaplasmids, pSymA and pSymB. Additionally, many indigenous S. meliloti strains possess one or more smaller plasmids, which represent the accessory genome of this species. Here we describe the complete nucleotide sequence of an accessory plasmid, designated pSmeSM11a, that was isolated from a dominant indigenous S. meliloti subpopulation in the context of a long-term field release experiment with genetically modified S. meliloti strains. Sequence analysis of plasmid pSmeSM11a revealed that it is 144,170 bp long and has a mean G+C content of 59.5 mol%. Annotation of the sequence resulted in a total of 160 coding sequences. Functional predictions could be made for 43% of the genes, whereas 57% of the genes encode hypothetical or unknown gene products. Two plasmid replication modules, one belonging to the repABC replicon family and the other belonging to the plasmid type A replicator region family, were identified. Plasmid pSmeSM11a contains a mobilization (mob) module composed of the type IV secretion system-related genes traG and traA and a putative mobC gene. A large continuous region that is about 42 kb long is very similar to a corresponding region located on S. meliloti Rm1021 megaplasmid pSymA. Single-base-pair deletions in the homologous regions are responsible for frameshifts that result in nonparalogous coding sequences. Plasmid pSmeSM11a carries additional copies of the nodulation genes nodP and nodQ that are responsible for Nod factor sulfation. Furthermore, a tauD gene encoding a putative taurine dioxygenase was identified on pSmeSM11a. An acdS gene located on pSmeSM11a is the first example of such a gene in S. meliloti. The deduced acdS gene product is able to deaminate 1-aminocyclopropane-1-carboxylate and is proposed to be involved in reducing the phytohormone ethylene, thus influencing nodulation events. The presence of numerous insertion sequences suggests that these elements mediated acquisition of accessory plasmid modules. PMID:16672515

Stiens, M.; Schneiker, S.; Keller, M.; Kuhn, S.; Puhler, A.; Schluter, A.

2006-01-01

216

Base isolation case study  

E-print Network

The primary objective of this thesis is the introduction of the current code, ASCE 7-05 into the base isolation design and the analysis of base isolation response due to seismic forces. An eight story irregular structure ...

Ching, Kenneth A. (Kenneth Apostol)

2008-01-01

217

Integrated optical isolators  

E-print Network

Introduction: Optical isolators are important components in lasers. Their main function is to eliminate noise caused by back-reflections into these lasers. The need for integrated isolators comes from the continuing growth ...

Zaman, Tauhid R

2005-01-01

218

Analog signal isolation techniques  

SciTech Connect

This paper discusses several techniques for isolating analog signals in an accelerator environment. The techniques presented here encompass isolation amplifiers, voltage-to-frequency converters (VIFCs), transformers, optocouplers, discrete fiber optics, and commercial fiber optic links. Included within the presentation of each method are the design issues that must be considered when selecting the isolation method for a specific application.

Beadle, E.R.

1992-01-01

219

Analog signal isolation techniques  

SciTech Connect

This paper discusses several techniques for isolating analog signals in an accelerator environment. The techniques presented here encompass isolation amplifiers, voltage-to-frequency converters (VIFCs), transformers, optocouplers, discrete fiber optics, and commercial fiber optic links. Included within the presentation of each method are the design issues that must be considered when selecting the isolation method for a specific application.

Beadle, E.R.

1992-12-31

220

Plastic Fiber Optical Isolator and Current Sensor  

Microsoft Academic Search

The Verdet constant of poly-alpha-methylstyrene fiber doped with a biphenyl compound showed a value beyond 0.09 min\\\\cdotOe-1\\\\cdotcm-1 at 488 nm. The optical fiber isolator for the 488-nm laser, which was constructed using the above plastic fiber and a pulse magnetic field, had about 20-dB isolation. This plastic fiber could also be used as an optical sensor head for monitoring higher

Shinzo Muto; Nobuo Seki; Takashi Suzuki; Toru Tsukamoto

1992-01-01

221

Seismic assessment of bridge structures isolated by a shape memory alloy/rubber-based isolation system  

NASA Astrophysics Data System (ADS)

This paper explores the effectiveness of shape memory alloy (SMA)/rubber-based isolation systems for seismic protection of bridges against near-field earthquakes by performing a sensitivity analysis. The isolation system considered in this study consists of a laminated rubber bearing, which provides lateral flexibility while supplying high vertical load-carrying capacity, and an auxiliary device made of multiple loops of SMA wires. The SMA device offers additional energy dissipating and re-centering capability. A three-span continuous bridge is modeled with the SMA/rubber-based (SRB) isolation system. Numerical simulations of the bridge are conducted for various near-field ground motions that are spectrally matched to a target design spectrum. The normalized forward transformation strength, forward transformation displacement and pre-strain level of the SMA device, ambient temperature and the lateral stiffness of the rubber bearings are selected as parameters of the sensitivity study. The variation of the seismic response of the bridge with the considered parameters is assessed. Also, the performance of the SRB isolation system with optimal design parameters is compared with an SMA-based sliding isolation system. The results indicate that the SRB isolation system can successfully reduce the seismic response of highway bridges; however, a smart isolation system that combines sliding bearings together with an SMA device is more efficient than the SRB isolation system.

Ozbulut, Osman E.; Hurlebaus, Stefan

2011-01-01

222

Genetic and antigenic variability in bovine viral diarrhea virus (BVDV) isolates from Belgium  

Microsoft Academic Search

This report describes the genetic and antigenic variability of bovine viral diarrhea virus strains isolated in Belgium. Part of the 5? untranslated region and the 5? end of the gp53 (E2) coding sequence were amplified by PCR and sequenced. Phylogenetic analysis showed that most field isolates segregated into genotypes Ib or II. Only one out of 28 field isolates belonged

B. Couvreur; C. Letellier; A. Collard; P. Quenon; P. Dehan; C. Hamers; P.-P. Pastoret; P. Kerkhofs

2002-01-01

223

Cell isolation and culture.  

PubMed

Cell isolation and culture are essential tools for the study of cell function. Isolated cells grown under controlled conditions can be manipulated and imaged at a level of resolution that is not possible in whole animals or even tissue explants. Recent advances have allowed for large-scale isolation and culture of primary C. elegans cells from both embryos and all four larval stages. Isolated cells can be used for single-cell profiling, electrophysiology, and high-resolution microscopy to assay cell autonomous development and behavior. This chapter describes protocols for the isolation and culture of C. elegans embryonic and larval stage cells. Our protocols describe isolation of embryonic and L1 stage cells from nematodes grown on high-density NA22 bacterial plates and isolation of L2 through L4 stage cells from nematodes grown in axenic liquid culture. Both embryonic and larval cells can be isolated from nematode populations within 3 hours and can be cultured for several days. A primer on sterile cell culture techniques is given in the appendices. PMID:23430760

Zhang, Sihui; Kuhn, Jeffrey R

2013-01-01

224

Interpersonal Exchange in Isolation.  

National Technical Information Service (NTIS)

The study explored interpersonal exchange in isolated and non-isolated groups. Nine dyads formed at different levels on need achievement, need dominance, need affiliation and dogmatism worked out lived in a small room for ten days, with no outside contact...

I. Altman, W. W. Haythorn

1965-01-01

225

MOX Fabrication Isolation Considerations  

SciTech Connect

This document provides a technical position on the preferred level of isolation to fabricate demonstration quantities of mixed oxide transmutation fuels. The Advanced Fuel Cycle Initiative should design and construct automated glovebox fabrication lines for this purpose. This level of isolation adequately protects the health and safety of workers and the general public for all mixed oxide (and other transmutation fuel) manufacturing efforts while retaining flexibility, allowing parallel development and setup, and minimizing capital expense. The basis regulations, issues, and advantages/disadvantages of five potential forms of isolation are summarized here as justification for selection of the preferred technical position.

Eric L. Shaber; Bradley J Schrader

2005-08-01

226

Assessment of the biocontrol potential of a Trichoderma viride isolate  

Microsoft Academic Search

A previous paper reported on the establishment of a field and fungal cellar trial set up to determine the biocontrol potential of a specific Trichoderma isolate against wood decay fungi. This paper reports on the analyses used to examine the protective effect of the selected isolate, and presents results indicating an initial protective effect against both basidiomycetes and soft rot

Heather L. Brown; Alan Bruce; Harry J. Staines

1999-01-01

227

Isolated vascular vertigo.  

PubMed

Strokes in the distribution of the posterior circulation may present with vertigo, imbalance, and nystagmus. Although the vertigo due to a posterior circulation stroke is usually associated with other neurologic symptoms or signs, small infarcts involving the cerebellum or brainstem can develop vertigo without other localizing symptoms. Approximately 11% of the patients with an isolated cerebellar infarction present with isolated vertigo, nystagmus, and postural unsteadiness mimicking acute peripheral vestibular disorders. The head impulse test can differentiate acute isolated vertigo associated with cerebellar strokes (particularly within the territory of the posterior inferior cerebellar artery) from more benign disorders involving the inner ear. Acute audiovestibular loss may herald impending infarction in the territory of anterior inferior cerebellar artery. Appropriate bedside evaluation is superior to MRIs for detecting central vascular vertigo syndromes. This article reviews the keys to diagnosis of acute isolated vertigo syndrome due to posterior circulation strokes involving the brainstem and cerebellum. PMID:25328871

Lee, Hyung

2014-09-01

228

Isolated Vascular Vertigo  

PubMed Central

Strokes in the distribution of the posterior circulation may present with vertigo, imbalance, and nystagmus. Although the vertigo due to a posterior circulation stroke is usually associated with other neurologic symptoms or signs, small infarcts involving the cerebellum or brainstem can develop vertigo without other localizing symptoms. Approximately 11% of the patients with an isolated cerebellar infarction present with isolated vertigo, nystagmus, and postural unsteadiness mimicking acute peripheral vestibular disorders. The head impulse test can differentiate acute isolated vertigo associated with cerebellar strokes (particularly within the territory of the posterior inferior cerebellar artery) from more benign disorders involving the inner ear. Acute audiovestibular loss may herald impending infarction in the territory of anterior inferior cerebellar artery. Appropriate bedside evaluation is superior to MRIs for detecting central vascular vertigo syndromes. This article reviews the keys to diagnosis of acute isolated vertigo syndrome due to posterior circulation strokes involving the brainstem and cerebellum. PMID:25328871

2014-01-01

229

Isolation of Human Eosinophils  

PubMed Central

Highly purified eosinophils can be isolated from peripheral blood by negative selection using an antibody-based magnetic negative selection protocol. The basic protocol describes a sequential fractionation of peripheral blood in which CD16+ granulocytes are enriched first from whole blood, followed by isolation of eosinophils. This technique is easy to use, fast, and highly reproducible. Support protocols describe a staining methods that can be used to evaluate the purity of eosinophils and differentiation from other leukocyte populations. PMID:22855360

Akuthota, Praveen; Shamri, Revital; Weller, Peter F.

2013-01-01

230

Isolated sleep paralysis  

PubMed Central

Sleep paralysis (SP) is a cardinal symptom of narcolepsy. However, little is available in the literature about isolated sleep paralysis. This report discusses the case of a patient with isolated sleep paralysis who progressed from mild to severe SP over 8 years. He also restarted drinking alcohol to be able to fall asleep and allay his anxiety symptoms. The patient was taught relaxation techniques and he showed complete remission of the symptoms of SP on follow up after 8 months. PMID:20711316

Sawant, Neena S.; Parkar, Shubhangi R.; Tambe, Ravindra

2005-01-01

231

Characterization of Salmonella Typhimurium isolates associated with septicemia in swine  

PubMed Central

Salmonella Typhimurium is frequently isolated from pigs and may also cause enteric disease in humans. In this study, 33 isolates of S. Typhimurium associated with septicemia in swine (CS) were compared to 33 isolates recovered from healthy animals at slaughter (WCS). The isolates were characterized using phenotyping and genotyping methods. For each isolate, the phage type, antimicrobial resistance, and pulsed-field gel electrophoresis (PFGE) DNA profiles were determined. In addition, the protein profiles of each isolate grown in different conditions were studied by Coomassie Blue-stained sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblot. Various phage types were identified. The phage type PT 104 represented 36.4% of all isolates from septicemic pigs. Resistance to as many as 12 antimicrobial agents, including some natural resistances, was found in isolates from CS and WCS. Many genetic profiles were identified among the PT 104 phage types. Although it was not possible to associate one particular protein with septicemic isolates, several highly immunogenic proteins, present in all virulent isolates and in most isolates from clinically healthy animals, were identified. These results indicated that strains associated with septicemia belong to various genetic lineages that can also be recovered from asymptomatic animals at the time of slaughter. PMID:20357952

Bergeron, Nadia; Corriveau, Jonathan; Letellier, Ann; Daigle, France; Quessy, Sylvain

2010-01-01

232

Comparison of dynamic response of isolated and non-isolated continuous girder bridges subjected to near-fault ground motions  

Microsoft Academic Search

The dynamic response of seismic isolated continuous girder bridges subjected to either near-fault or far-field ground motions is compared to the non-isolated ones. Near-fault earthquake ground motion data are collected from the 1999 Taiwan Chi-Chi earthquake. The earthquake data recorded at the same sites from other events serve as far-field ground motions. Typical three-span continuous concrete box girder bridges designed

Wen-I Liao; Chin-Hsiung Loh; Bor-Han Lee

2004-01-01

233

Combination field plate\\/field ring termination structures for integrated power devices  

Microsoft Academic Search

The issues associated with termination structure design for vertical, integrated power devices are defined. The interaction of the oxide thickness running over the device isolation and the breakdown voltage of the device is explored. In light of these constraints, a comparison of single field plate, two-level field plate, field ring only, and combination field plate\\/field ring termination structures is performed.

S. L. Kosier; A. Wei; M. A. Shibib; J. C. Desko; R. D. Schrimpf; K. F. Galloway; K. C. Yau

1993-01-01

234

Comparative evaluation of an automated ribotyping system versus pulsed-field gel electrophoresis for epidemiological typing of clinical isolates of Escherichia coli and Pseudomonas aeruginosa from patients with recurrent gram-negative bacteremia  

Microsoft Academic Search

Ribotyping and macrorestriction analysis of chromosomal DNA using pulsed-field gel electrophoresis (PFGE) are among the more useful molecular epidemiologic typing methods. Because these techniques are labor intensive, automation of one or more steps may allow clinical laboratories to apply molecular typing methods. We compared the recently developed automated ribotyping system, the RiboPrinter™ Microbial Characterization System (DuPont), with PFGE as a

M. A. Pfaller; C. Wendt; R. J. Hollis; R. P. Wenzel; S. J. Fritschel; J. J. Neubauer; L. A. Herwaldt

1996-01-01

235

A novel approach for the isolation of the sound and pseudo-sound contributions from near-field pressure fluctuation measurements: analysis of the hydroacoustic and hydrodynamic perturbation in a propeller-rudder system  

NASA Astrophysics Data System (ADS)

The main scope of the present work is to investigate the mechanisms underlying the hydroacoustic and hydrodynamic perturbations in a rudder operating in the wake of a free running marine propeller. The study consisted of detailed near-field pressure fluctuation measurements which were acquired on the face and back surfaces of the rudder, at different deflection angles. To this aim, a novel wavelet-filtering procedure was applied to separate and analyze distinctly the acoustic and hydrodynamic components of the recorded near-field pressure signals. The filtering procedure undertakes the separation of intermittent pressure peaks induced by the passage of eddy structures, interpreted as pseudo-sound, from homogenous background fluctuations, interpreted as sound. The use of wavelet in the filtering procedure allows to overcome the limitations of the earlier attempts based on frequency (wave number) band-pass filtering, retrieving the overall frequency content of both the acoustic and the hydrodynamic components and returning them as independent signals in the time domain. Acoustic and hydrodynamic pressure distributions were decomposed harmonically and compared to the corresponding topologies of the vorticity field, derived from earlier LDV measurements performed by Felli and Falchi (Exp Fluids 51(5):1385-1402, 2011). The study highlighted that the acoustic perturbation is mainly correlated with the unsteady load variations of the rudder and to the shear layer fluctuations of the propeller streamtube. Conversely, the dynamics of the propeller tip and hub vortices underlies the hydrodynamic perturbation.

Felli, Mario; Grizzi, Silvano; Falchi, Massimo

2014-01-01

236

Influenza virus isolation.  

PubMed

The isolation of influenza viruses is important for the diagnosis of respiratory diseases in lower animals and humans, for the detection of the infecting agent in surveillance programs, and is an essential element in the development and production of vaccine. Since influenza is caused by a zoonotic virus it is necessary to do surveillance in the reservoir species (aquatic waterfowls), intermediate hosts (quails, pigs), and in affected mammals including humans. Two of the hemagglutinin (HA) subtypes of influenza A viruses (H5 and H7) can evolve into highly pathogenic (HP) strains for gallinaceous poultry; some HP H5 and H7 strains cause lethal infection of humans. In waterfowls, low pathogenic avian influenza (LPAI) isolates are obtained primarily from the cloaca (or feces); in domestic poultry, the virus is more often recovered from the respiratory tract than from cloacal samples; in mammals, the virus is most often isolated from the respiratory tract, and in cases of high pathogenic avian influenza (HPAI) from the blood and internal organs of infected birds. Virus isolation procedures are performed by inoculation of clinical specimens into embryonated eggs (primarily chicken eggs) or onto a variety of primary or continuous tissue culture systems. Successful isolation of influenza virus depends on the quality of the sample and matching the appropriate culture method to the sample type. PMID:22528151

Krauss, Scott; Walker, David; Webster, Robert G

2012-01-01

237

Fasciola hepatica: histological demonstration of apoptosis in the reproductive organs of flukes of triclabendazole-sensitive and triclabendazole-resistant isolates, and in field-derived flukes from triclabendazole-treated hosts, using in situ hybridisation to visualise endonuclease-generated DNA strand breaks.  

PubMed

Investigation of the triclabendazole (TCBZ) resistance status of populations of Fasciola hepatica in field cases of fasciolosis, where treatment failure has been reported, can be supported by histological examination of flukes collected from recently treated hosts. In TCBZ-sensitive flukes (TCBZ-S) exposed to TCBZ metabolites for 1-4days in vivo, but not in TCBZ-resistant flukes (TCBZ-R), morphological changes suggestive of apoptosis occur in cells undergoing meiosis or mitosis in the testis, ovary and vitelline follicles. In order to verify or refute the contention that efficacy of TCBZ treatment is associated with apoptosis in the reproductive organs of flukes, histological sections of TCBZ-S (Cullompton isolate) flukes and TCBZ-R (Sligo isolate) flukes were subjected to the TdT-mediated dUDP nick end labelling (TUNEL) in situ hybridisation method, a commercially available test specifically designed to label endonuclease-induced DNA strand breaks associated with apoptosis. Additionally, sections of in vivo-treated and untreated flukes originating from field outbreaks of suspected TCBZ-S and TCBZ-R fasciolosis were labelled by the TUNEL method. It was found that in treated TCBZ-S flukes, strong positive labelling indicating apoptosis was associated with morphologically abnormal cells undergoing mitosis or meiosis in the testis, ovary and vitelline follicles. Background labelling in the positive testis sections was attributed to heterophagy of cell debris by the sustentacular tissue. The triggering of apoptosis was probably related to failure of spindle formation at cell division, supporting the contention that TCBZ inhibits microtubule formation. In treated TCBZ-R (Sligo Type 1) flukes, and in treated flukes from field outbreaks of suspected TCBZ-R fasciolosis, no significant labelling was observed, while sections of fluke derived from a field case of fasciolosis where TCBZ resistance was not suspected were heavily labelled. Light labelling was associated with the testis of untreated Cullompton (TCBZ-S) and Sligo Type 2 (TCBZ-R) flukes, which exhibit abnormal spermatogenesis and spermiogenesis, respectively. This was attributed to apoptosis and to heterophagy of effete germ line cells by the sustentacular tissue. It is concluded that demonstration of apoptosis by in situ hybridisation using the TUNEL method on sections of 1-4days in vivo TCBZ-treated F. hepatica can contribute to the diagnosis of TCBZ resistance in field outbreaks of fasciolosis. PMID:23062689

Hanna, R E B; Forster, F I; Brennan, G P; Fairweather, I

2013-01-31

238

Nucleic acid isolation process  

DOEpatents

A method is provided for isolating DNA from eukaryotic cell and flow sorted chromosomes. When DNA is removed from chromosome and cell structure, detergent and proteolytic digestion products remain with the DNA. These products can be removed with organic extraction, but the process steps associated with organic extraction reduce the size of DNA fragments available for experimental use. The present process removes the waste products by dialyzing a solution containing the DNA against a solution containing polyethylene glycol (PEG). The waste products dialyze into the PEG leaving isolated DNA. The remaining DNA has been prepared with fragments containing more than 160 kb. The isolated DNA has been used in conventional protocols without affect on the protocol.

Longmire, Jonathan L. (Los Alamos, NM); Lewis, Annette K. (La Jolla, CA); Hildebrand, Carl E. (Los Alamos, NM)

1990-01-01

239

Nucleic acid isolation  

DOEpatents

A method is provided for isolating DNA from eukaryotic cell and flow sorted chromosomes. When DNA is removed from chromosome and cell structure, detergent and proteolytic digestion products remain with the DNA. These products can be removed with organic extraction, but the process steps associated with organic extraction reduces the size of DNA fragments available for experimental use. The present process removes the waste products by dialyzing a solution containing the DNA against a solution containing polyethylene glycol (PEG). The waste products dialyze into the PEG leaving isolated DNA. The remaining DNA has been prepared with fragments containing more than 160 kb. The isolated DNA has been used in conventional protocols without effect on the protocol.

Longmire, J.L.; Lewis, A.K.; Hildebrand, C.E.

1988-01-21

240

High voltage gas isolator  

NASA Technical Reports Server (NTRS)

An isolator is provided which has an inlet at ground electrical potential which receives gas, and which has an outlet at a high electrical potential through which gas is discharged, the isolator being compactly and simply constructed while providing a long narrow path that minimizes the possibility of electrical breakdown through the gas. The isolator includes a first element forming a cylindrical core and a cup-shaped second element forming a sleeve portion that closely receives the core. The core has a helical groove on its outside to form a passage between the groove and the inner walls of the sleeve. The core also has a vertical hole extending to the bottom of the core and a radial groove in the bottom of the core that extends between the hole and the bottom of the helical groove.

Brophy, John R. (Inventor)

1988-01-01

241

Clinical, pathological and antigenic aspects of bovine viral diarrhea virus (BVDV) type 2 isolates identified in Brazil  

Microsoft Academic Search

Nucleotide sequencing and phylogenetic analysis of Brazilian bovine viral diarrhea virus (BVDV) field isolates identified four viruses belonging to the genotype 2. Comparison of 5? UTR sequences from these isolates to those of North American BVDV type 2 revealed genomic variations that correlated with the geographic origins of the isolates. Two of the Brazilian type 2 viruses were isolated from

E. F Flores; L. H. G. V Gil; S. A Botton; R Weiblen; J. F Ridpath; L. C Kreutz; C Pilati; D Driemeyer; V Moojen; A. C Wendelstein

2000-01-01

242

Review on Recent Advances in the Analysis of Isolated Organelles  

PubMed Central

The analysis of isolated organelles is one of the pillars of modern bioanalytical chemistry. This review describes recent developments on the isolation and characterization of isolated organelles both from living organisms and cell cultures. Salient reports on methods to release organelles focused on reproducibility and yield, membrane isolation, and integrated devices for organelle release. New developments on organelle fractionation after their isolation were on the topics of centrifugation, immunocapture, free flow electrophoresis, flow field-flow fractionation, fluorescence activated organelle sorting, laser capture microdissection, and dielectrophoresis. New concepts on characterization of isolated organelles included atomic force microscopy, optical tweezers combined with Raman spectroscopy, organelle sensors, flow cytometry, capillary electrophoresis, and microfluidic devices. PMID:23107131

Satori, Chad P.; Kostal, Vratislav; Arriaga, Edgar A.

2012-01-01

243

Genetic diversity of Gallibacterium anatis isolates from different chicken flocks.  

PubMed

Amplified fragment length polymorphisms (AFLPs) were used to characterize the genotypic diversity of a total of 114 Gallibacterium anatis isolates originating from a reference collection representing 15 biovars from four countries and isolates obtained from tracheal and cloacal swab samples of chickens from an organic, egg-producing flock and a layer parent flock. A subset of strains was also characterized by pulsed-field gel electrophoresis and biotyping. The organic flock isolates were characterized by more than 94% genetic similarity, indicating that only a single clone was apparent in the flock. The layer parent flock isolates were grouped into two subclusters, each with similarity above 90%. One subcluster contained only tracheal isolates, while the other primarily included cloacal isolates. In conclusion, we show that AFLP analysis enables fingerprinting of G. anatis, which seems to have a clonal population structure within natural populations. There was further evidence of clonal lineages, which may have adapted to different sites within the same animal. PMID:12791918

Bojesen, Anders Miki; Torpdahl, Mia; Christensen, Henrik; Olsen, John Elmerdahl; Bisgaard, Magne

2003-06-01

244

Isolated Fallopian Tube Torsion  

PubMed Central

Isolated torsion of the Fallopian tube is a rare gynecological cause of acute lower abdominal pain, and diagnosis is difficult. There are no pathognomonic symptoms; clinical, imaging, or laboratory findings. A preoperative ultrasound showing tubular adnexal masses of heterogeneous echogenicity with cystic component is often present. Diagnosis can rarely be made before operation, and laparoscopy is necessary to establish the diagnosis. Unfortunately, surgery often is performed too late for tube conservation. Isolated Fallopian tube torsion should be suspected in case of acute pelvic pain, and prompt intervention is necessary. PMID:23984132

Kardakis, S.; Barranca, A.; Vitelli, A.; Amore, I.; Trento, F.; Caccia, G.

2013-01-01

245

Detection of antibodies against porcine epidemic diarrhea virus in serum and colostrum by indirect ELISA.  

PubMed

An indirect porcine epidemic diarrhea virus (PEDV) anti-immunoglobulin (Ig) G ELISA based on the S1 portion of the spike protein was validated and compared with an indirect immunofluorescence assay. In serum samples from experimentally infected pigs (n?=?35), anti-IgG PEDV antibodies were detected as early as 7 days post-infection. In field serum samples (n?=?239), the diagnostic sensitivity of the S1 ELISA was 100% and the diagnostic specificity was 94%. The S1 ELISA showed no cross-reactivity with antibodies against other porcine coronaviruses. Colostrum samples (n?=?133) were also tested for anti-PEDV IgG and IgA. The diagnostic sensitivity was 92% for IgG and 100% for IgA, and the diagnostic specificity was 90% for IgG and 99.4% for IgA. These data suggest that the S1 ELISA is a sensitive and specific test that could also be used to evaluate PEDV colostral immunity. PMID:25135339

Gerber, Priscilla F; Gong, Qiaoling; Huang, Yao-Wei; Wang, Chong; Holtkamp, Derald; Opriessnig, Tanja

2014-10-01

246

The genotypic characterization of Cronobacter spp. isolated in China.  

PubMed

Cronobacter spp. (Enterobacter sakazakii) is an important pathogen contaminating powdered infant formula (PIF). To describe the genotypic diversity of Cronobacter isolated in China, we identified the isolates using fusA allele sequencing, and subtyped all of the isolates using pulsed-field gel electrophoresis (PFGE), multi-locus sequence typing (MLST), and multiple-locus variable-number tandem-repeat analysis (MLVA). A total of 105 isolates were identified, which included C. sakazakii (58 isolates), C. malonaticus (30 isolates), C. dublinensis (11 isolates), C. turicensis (5 isolates), and C. muytjensii (1 isolate). These isolates were showed to have 85 PFGE-patterns, 71 sequence types (STs), and 55 MLVA-patterns. Comparisons among the three molecular subtyping methods revealed that the PFGE method was the most distinguishable tool in identifying clusters of Cronobacter spp. through DNA fingerprinting, and MLST method came second. However, ESTR-1, ESTR-2, ESTR-3, and ESTR-4 were not effective loci for subtyping Cronobacter spp. such that the MLVA method requires further improvement. PMID:25029018

Cui, Jinghua; Du, Xiaoli; Liu, Hui; Hu, Guangchun; Lv, Guoping; Xu, Baohong; Yang, Xiaorong; Li, Wei; Cui, Zhigang

2014-01-01

247

Breaking Down Racial Isolation.  

ERIC Educational Resources Information Center

Describes the "Across the Lines" project involving an interchange between students and teachers of two racially isolated schools in the Hartford (Connecticut) area. A racial mix of 50/50 was achieved through planned science museum visits, randomly paired pen pals, and an MCI electronic mail connection between schools. (MLH)

Foster, Lloyd A.

1989-01-01

248

Reproductive Isolation in Angiosperms  

NSDL National Science Digital Library

This resource is a suitable exercise for use in plant reproductive biology laboratory courses. Its purpose is to illustrate mechanisms of isolation in angiosperms by the species Silene by observing the success or failure of inter-specific pollination. This lab exercise is also suitable for courses in plant biology, concepts of the biological species or botany, and evolution.

Alexander F. Motten (Duke University;)

1996-01-01

249

Scalable statistical bug isolation  

Microsoft Academic Search

We present a statistical debugging algorithm that isolates bugs in programs containing multiple undiagnosed bugs. Earlier statistical algorithms that focus solely on identifying predictors that correlate with program failure perform poorly when there are multiple bugs. Our new technique separates the effects of different bugs and identifies predictors that are associated with individual bugs. These predictors reveal both the circumstances

Ben Liblit; Mayur Naik; Alice X. Zheng; Alexander Aiken; Michael I. Jordan

2005-01-01

250

Chemical Kinetics: Isolation Method  

NSDL National Science Digital Library

This site offers an interactive tutorial that guides the student through the Method of Isolation used for the determination of chemical reaction rate laws and rate constants. This tutorial is coupled to others to further guide the student to a better understanding of chemical kinetics.

Blauch, David N.

251

Biological Isolation Garment  

NASA Technical Reports Server (NTRS)

A spinoff of astronaut's biological garment will allow hospital patients who are highly vulnerable to infection to leave their sterile habitats for several hours, carrying their germ free environment with them. Garments can be used in any of some 200 hospitals where isolation rooms are installed to treat leukemia.

1976-01-01

252

Diversity of salmonella isolates from central Florida surface waters.  

PubMed

Identification of Salmonella serotypes is important for understanding the environmental diversity of the genus Salmonella. This study evaluates the diversity of Salmonella isolates recovered from 165 of 202 Central Florida surface water samples and investigates whether the serotype of the environmental Salmonella isolates can be predicted by a previously published multiplex PCR assay (S. Kim, J. G. Frye, J. Hu, P. J. Fedorka-Cray, R. Gautom, and D. S. Boyle, J. Clin. Microbiol. 44:3608-3615, 2006, http://dx.doi.org/10.1128/JCM.00701-06). Multiplex PCR was performed on 562 Salmonella isolates (as many as 36 isolates per water sample) to predict serotypes. Kauffmann-White serogrouping was used to confirm multiplex PCR pattern groupings before isolates were serotyped, analyzed by pulsed-field gel electrophoresis, and assayed for antimicrobial susceptibility. In 41.2% of the Salmonella-positive water samples, all Salmonella isolates had identical multiplex PCR patterns; in the remaining 58.8%, two or more multiplex PCR patterns were identified. Within each sample, isolates with matching multiplex PCR patterns had matching serogroups. The multiplex patterns of 495 isolates (88.1%) did not match any previously reported pattern. The remaining 68 isolates matched reported patterns but did not match the serotypes for those patterns. The use of the multiplex PCR allowed the number of isolates requiring further analysis to be reduced to 223. Thirty-three Salmonella enterica serotypes were identified; the most frequent included serotypes Muenchen, Rubislaw, Anatum, Gaminara, and IV_50:z4,z23:-. A majority (141/223) of Salmonella isolates clustered into one genotypic group. Salmonella isolates in Central Florida surface waters are serotypically, genotypically, and phenotypically (in terms of antimicrobial susceptibility) diverse. While isolates could be grouped as different or potentially the same using multiplex PCR, the multiplex PCR pattern did not predict the Salmonella serotype. PMID:25172861

McEgan, Rachel; Chandler, Jeffrey C; Goodridge, Lawrence D; Danyluk, Michelle D

2014-11-01

253

Dynamics of the isolated galaxy CIG 0314  

E-print Network

In the context of the AMIGA project, we used Fabry-Perot observations in order to study the dynamics of the ionised gas in the isolated galaxy CIG 0314. From the Halpha observations, we could obtain the velocity field and rotation curve of the galaxy. A detail analysis of the velocity field is done in order to understand the kinematics of the gas to gather clues on the mechanisms which favour or inhibit star formation, in particular along the bar. The visible and dark matter content can be reached, as well as an estimation of the mass of the galaxy.

Verley, S; Repetto, P; Gabbasov, R; Verdes-Montenegro, L; Bergond, G; Fuentes-Carrera, I; Durbala, A

2009-01-01

254

DNA Isolation from Onion  

NSDL National Science Digital Library

Many students find studying DNA difficult because it is so small that the concepts are quite abstract. This lab enables students to work with DNA concretely by easily isolating chromosomal DNA using the same basic tools and methods that scientists use. The lab is a good introduction to using pipets and to using the metric system. If the chemistry of the solutions is taught it is also a great practical application.

Kate Dollard (Cambridge Rindge and Latin REV)

1994-07-30

255

Mechanical beam isolator  

SciTech Connect

Back-reflections from a target, lenses, etc. can gain energy passing backwards through a laser just like the main beam gains energy passing forwards. Unless something blocks these back-reflections early in their path, they can seriously damage the laser. A Mechanical Beam Isolator is a device that blocks back-reflections early, relatively inexpensively, and without introducing aberrations to the laser beam.

Post, R.F.; Vann, C.S.

1996-10-01

256

Assessment of Waveguide Vibration Isolator.  

National Technical Information Service (NTIS)

A method is proposed for comparing the dynamic performance of different types of vibration isolators, and relies on having equal compression ratios of the rubber elements. The method is used to compare a waveguide vibration isolator with a blank vibration...

J. D. Dickens

1999-01-01

257

Methicillin-resistant Staphylococcus aureus (MRSA) isolated at Fukuoka University Hospital and hospitals and clinics in the Fukuoka city area  

Microsoft Academic Search

Bacteriological and epidemiological studies were carried out on 106 isolates of methicillin-resistant Staphylococcus aureus (MRSA) isolated at our hospital (56 isolates) and from 15 other hospitals and clinics (50 isolates) in the Fukuoka city area. Strains were studied regarding coagulase-type, ?-lactamase production, and antimicrobial susceptibility; genotype studies used pulsed-field gel electrophoresis (PFGE) with cluster analysis. The majority of isolates produced

Seiji Takeda; Kakuko Yasunaka; Kenji Kono; Kikuo Arakawa

2000-01-01

258

Characterization of toxin plasmids in Clostridium perfringens type C isolates.  

PubMed

Clostridium perfringens type C isolates cause enteritis necroticans in humans or necrotizing enteritis and enterotoxemia in domestic animals. Type C isolates always produce alpha toxin and beta toxin but often produce additional toxins, e.g., beta2 toxin or enterotoxin. Since plasmid carriage of toxin-encoding genes has not been systematically investigated for type C isolates, the current study used Southern blot hybridization of pulsed-field gels to test whether several toxin genes are plasmid borne among a collection of type C isolates. Those analyses revealed that the surveyed type C isolates carry their beta toxin-encoding gene (cpb) on plasmids ranging in size from ?65 to ?110 kb. When present in these type C isolates, the beta2 toxin gene localized to plasmids distinct from the cpb plasmid. However, some enterotoxin-positive type C isolates appeared to carry their enterotoxin-encoding cpe gene on a cpb plasmid. The tpeL gene encoding the large clostridial cytotoxin was localized to the cpb plasmids of some cpe-negative type C isolates. The cpb plasmids in most surveyed isolates were found to carry both IS1151 sequences and the tcp genes, which can mediate conjugative C. perfringens plasmid transfer. A dcm gene, which is often present near C. perfringens plasmid-borne toxin genes, was identified upstream of the cpb gene in many type C isolates. Overlapping PCR analyses suggested that the toxin-encoding plasmids of the surveyed type C isolates differ from the cpe plasmids of type A isolates. These findings provide new insight into plasmids of proven or potential importance for type C virulence. PMID:20823204

Gurjar, Abhijit; Li, Jihong; McClane, Bruce A

2010-11-01

259

Numerical investigation of smart base isolation system employing MR elastomer  

NASA Astrophysics Data System (ADS)

This paper evaluates the dynamic performance of a newly proposed smart base isolation system employing Magneto-Rheological Elastomers (MREs). MREs belong to a class of smart materials whose elastic modulus or stiffness can be adjusted by varying the magnitude of the magnetic field. The base isolation systems are considered as one of the most effective devices for vibration reduction of civil engineering structures in the event of earthquakes. The proposed base isolation system strives to enhance the performance of the conventional base-isolation system by using controllable MREs. To validate the effectiveness of the MRE-based isolation system, an extensive simulation study has been performed using a five degree-of-freedom structure under several historical earthquake excitations. The results show that the proposed system outperformed the conventional system in reducing the responses of the structure in all the seismic excitations considered in the study.

Usman, M.; Sung, S. H.; Jang, D. D.; Jung, H. J.; Koo, J. H.

2009-02-01

260

Direct cardiotoxic effects of cocaine and cocaethylene on isolated cardiomyocytes  

Microsoft Academic Search

We investigated the cardiotoxic effects of cocaine and cocaethylene on the Ca2+ flux responsible for excitation-contraction coupling in isolated ventricular rat myocytes. We simultaneously measured intracellular Ca2+ transients and cell length in isolated cardiac myocytes loaded with a fluorescent Ca2+ indicator, indo-1, during electrical field stimulation at 1 Hz. The cell length was estimated by video dimension analysis. We also

Hongcheng Bai; Kinya Otsu; Mohammed Nasimul Islam; Hisanaga Kuroki; Masaru Terada; Michihiko Tada; Choei Wakasugi

1996-01-01

261

Mycobacteria isolated from exotic animals.  

PubMed

Mycobacteria were isolated from 263 of 474 specimens submitted from captive exotic (nondomesticated) animals over a 5-year period. Mycobacterium avium was isolated from 128 animals originating in 13 states and the District of Columbia; serotype 1 accounted for 65 of the isolations. Mycobacterium bovi was isolated from 74 animals in 7 zoos, 7 game parks, and 4 primate colonies in 1, states: Mycobacterium tuberculosis was isolated from 29 animals originating 9 stats; and Mycobacterium fortuitum, Mycobacterium chelonei, Mycobacterium scrofulaceum, and Mycobacterium spp. The widespread occurrence of tuberculosis in exotic animals maintained in captivity emphasizes the public health importance of these infections. PMID:406254

Thoen, C O; Richards, W D; Jarnagin, J L

1977-05-01

262

The NASA Langley Isolator Dynamics Research Lab  

NASA Technical Reports Server (NTRS)

The Isolator Dynamics Research Lab (IDRL) is under construction at the NASA Langley Research Center in Hampton, Virginia. A unique test apparatus is being fabricated to support both wall and in-stream measurements for investigating the internal flow of a dual-mode scramjet isolator model. The test section is 24 inches long with a 1-inch by 2-inch cross sectional area and is supplied with unheated, dry air through a Mach 2.5 converging-diverging nozzle. The test section is being fabricated with two sets (glass and metallic) of interchangeable sidewalls to support flow visualization and laser-based measurement techniques as well as static pressure, wall temperature, and high frequency pressure measurements. During 2010, a CFD code validation experiment will be conducted in the lab in support of NASA s Fundamental Aerodynamics Program. This paper describes the mechanical design of the Isolator Dynamics Research Lab test apparatus and presents a summary of the measurement techniques planned for investigating the internal flow field of a scramjet isolator model.

Middleton, Troy F.; Balla, Robert J.; Baurle, Robert A.; Humphreys, William M.; Wilson, Lloyd G.

2010-01-01

263

Geological problems in radioactive waste isolation  

SciTech Connect

The problem of isolating radioactive wastes from the biosphere presents specialists in the fields of earth sciences with some of the most complicated problems they have ever encountered. This is especially true for high level waste (HLW) which must be isolated in the underground and away from the biosphere for thousands of years. Essentially every country that is generating electricity in nuclear power plants is faced with the problem of isolating the radioactive wastes that are produced. The general consensus is that this can be accomplished by selecting an appropriate geologic setting and carefully designing the rock repository. Much new technology is being developed to solve the problems that have been raised and there is a continuing need to publish the results of new developments for the benefit of all concerned. The 28th International Geologic Congress that was held July 9--19, 1989 in Washington, DC provided an opportunity for earth scientists to gather for detailed discussions on these problems. Workshop W3B on the subject, Geological Problems in Radioactive Waste Isolation -- A World Wide Review'' was organized by Paul A Witherspoon and Ghislain de Marsily and convened July 15--16, 1989 Reports from 19 countries have been gathered for this publication. Individual papers have been cataloged separately.

Witherspoon, P.A. (ed.)

1991-01-01

264

Giardia isolates from primates and rodents display the same molecular polymorphism as human isolates.  

PubMed

Five Giardia isolates from primates and rodents were grown axenically and compared by different electrophoretic techniques. One isolate from a lemur (slow loris) contained a dsRNA virus also found in some of the Giardia of human origin. Using ethidium bromide stained gels and also Southern blots hybridized with a rDNA probe, two profiles of restriction fragment length polymorphism were found in the animal Giardia, which are identical to two profiles found previously in strains of human origin. Isoenzyme and total protein patterns obtained with agarose isoelectric focusing divided the strains in the same two groups. With pulsed field gradient gel electrophoresis, the isolates showed 6-8 chromosomal bands but none of the band patterns were identical. The size of the chromosomes varied from 0.8 to over 3.0 Mb. A ribosomal DNA probe hybridized with different bands. PMID:1968225

De Jonckheere, J F; Majewska, A C; Kasprzak, W

1990-02-01

265

Identification of the main toxins isolated from Fusarium oxysporum f. sp. pisi race 2 and their relation with isolates' pathogenicity.  

PubMed

Fusarium oxysporum f. sp. pisi (Fop) is a pathogen of field pea inducing severe vascular wilt worldwide. Plant resistance to races 1, 5, and 6, producing wilt symptoms, is conferred by a single dominant gene, while resistance to race 2, which gives near-wilt symptoms, have been recently showed to be quantitative. Among the virulence factors reported to play a role in the infection process, toxin production is one of the best studied. Thus, five race 2 isolates have been investigated for toxin production in vitro and their relation to isolates' pathogenicity. All the isolates produced different amounts of fusaric and 9,10-dehydrofusaric acids. The content of the two toxins has been quantitated and correlated with the pathogenicity and aggressiveness of isolates on field pea. Results suggested that toxin production is an important determinant of Fop race 2 pathogenicity. PMID:24568659

Bani, Moustafa; Rispail, Nicolas; Evidente, Antonio; Rubiales, Diego; Cimmino, Alessio

2014-03-26

266

Isolated Coccygeal Tuberculosis  

PubMed Central

Isolated tuberculosis of the coccyx is extremely rare. A 35-year-old man presented with a 3-month history of coccygeal and gluteal pain. Computed tomography and magnetic resonance imaging revealed osseous destruction and a large enhancing mass involving the coccyx with anterior and posterior extension. Pathologic examination of the surgical specimen revealed necrosis, chronic granulomatous inflammation, and multinucleated giant cells consistent with tuberculosis. This case highlights the importance of considering tuberculosis as a diagnosis even though unusual sites are involved. PMID:23323174

Kim, Do Un; Ju, Chang IL

2012-01-01

267

Investigation of mercury thruster isolators  

NASA Technical Reports Server (NTRS)

Mercury ion thruster isolator lifetime tests were performed using different isolator materials and geometries. Tests were performed with and without the flow of mercury through the isolators in an oil diffusion pumped vacuum facility and cryogenically pumped bell jar. The onset of leakage current in isolators occurred in time intervals ranging from a few hours to many hundreds of hours. In all cases, surface contamination was responsible for the onset of leakage current and subsequent isolator failure. Rate of increase of leakage current and the leakage current level increased approximately exponentially with isolator temperature. Careful attention to shielding techniques and the elimination of sources of metal oxides appear to have eliminated isolator failures as a thruster life limiting mechanism.

Mantenieks, M. A.

1973-01-01

268

Statistical comparison of isolated and non-isolated auroral substorms  

NASA Astrophysics Data System (ADS)

We present results from a superposed epoch analysis of the morphology and energy deposition of isolated and non-isolated auroral substorms. The study is based on auroral data acquired by the global ultraviolet imager (GUVI) on board the TIMED satellite and a total number of 13717 geomagnetic bay onsets identified with magnetometer data from SuperMAG and published previously by Newell and Gjerloev [2011]. Here the isolated substorms are those having separation of two consecutive onsets no less than 3 hours. While the three phases substorm are clearly shown in both isolated and non-isolated substorms, there are noticeable differences between the two types of substorms: (1) In the growth phase, the nighttime auroral power slightly increases for both types of substorms; isolated (non-isolated) substorms are associated with smaller (greater) nighttime auroral power; (2) In the expansion phase, substorm energy release is greater and more explosive for isolated than non-isolated substorms; (3) The recovery phase period is longer for isolated than for non-isolated substorms; (4) The winter-to-summer auroral power ratio is approximately constant throughout the three substorm phases and the ratio is larger for isolated (30%) than for non-isolated (20%) substorms. We also found that the polar cap area increases during the growth phase until ~10 min prior to the magnetic substorm onset and decreases rapidly after onset. The decrease is associated with the closure of the nightside auroral oval associated with substorm expansion. We found most of these differences can be related to the differences in their solar wind driving. We will present the results in detail and make a conclusion.

Liou, K.; Newell, P. T.; Zhang, Y.; Paxton, L. J.

2012-12-01

269

Carbon nanotube-based field ionization vacuum  

E-print Network

We report the development of a novel micropump architecture that uses arrays of isolated vertical carbon nanotubes (CNT) to field ionize gas particles. The ionized gas molecules are accelerated to and implanted into a ...

Jang, Daniel, M. Eng. Massachusetts Institute of Technology

2012-01-01

270

Field Notes  

USGS Multimedia Gallery

The Field Records Collection has many materials types including: field notebooks, sketches, annotated maps, unpublished manuscripts, plane-table sheets, annotated aerial photographs, sample analysis, stratigraphic columns, lithologic logs, and geologic cross sections. Materials in the Field Records ...

2009-04-09

271

Relatedness of Listeria monocytogenes Isolates Recovered from Selected Ready-To-Eat Foods and Listeriosis Patients in the United States  

PubMed Central

Pulsed-field gel electrophoresis and serotyping were performed for 544 isolates of Listeria monocytogenes, including 502 isolates recovered from contaminated samples from 31,705 retail ready-to-eat (RTE) food products and 42 isolates recovered from human cases of listeriosis. The isolates were from Maryland (294 isolates) and California (250 isolates) and were collected in 2000 and 2001. The isolates were placed into 16 AscI pulsogroups (level of relatedness within each group, ?66%), 139 AscI pulsotypes (levels of relatedness, ?25% to 100%), and eight serotypes (serotypes 1/2a, 1/2b, 1/2c, 3a, 3b, 4b, 4c, and 4d). The most frequently found pulsotypes belonged to either pulsogroup A (150 food isolates plus 4 clinical isolates) or pulsogroup B (104 food isolates plus 5 clinical isolates). The majority of the 502 food isolates were either serotype 1/2a (298 isolates) or serotype 1/2b (133 isolates), whereas the majority of the 42 clinical isolates were either serotype 1/2a (19 isolates) or serotype 4b (15 isolates). Additionally, 13 clinical isolates displayed pulsotypes also found in food isolates, whereas the remaining 29 clinical isolates displayed 24 unique pulsotypes. These data indicate that most (86%) of the L. monocytogenes subtypes found in the RTE foods sampled belonged to only two serotypes and that 90% of the isolates displayed 73 pulsotypes, with 107 isolates displaying pulsotype 1. These data should help define the distribution and relatedness of isolates found in RTE foods in comparison with isolates that cause listeriosis. PMID:16332793

Gilbreth, Stefanie Evans; Call, Jeff E.; Wallace, F. Morgan; Scott, Virginia N.; Chen, Yuhuan; Luchansky, John B.

2005-01-01

272

Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea  

PubMed Central

The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

2014-01-01

273

Isolated neutron stars discovered by ROSAT  

E-print Network

ROSAT has discovered a new group of isolated neutron stars characterized by soft black-body like spectra (kT ~ 50-120 eV), apparent absence of radio emission and no association with supernovae remnants. So far only six such sources are known. A small fraction of these stars exhibit X-ray pulsations with relatively long periods of the order of 10 sec. Two very different mechanisms may be envisaged to explain their properties. The neutron stars may be old and re-heated by accretion from the ISM in which case their population properties could provide information on past stellar formation and secular magnetic field decay. Alternatively, this group may at least partly be made of relatively young cooling neutron stars possibly descendant from magnetars. We review the last observational results and show how they can shed light on the evolutionary path of these new objects within the whole class of isolated neutron stars.

C. Motch

2000-08-30

274

Mosser Damper: Steam turbine isolation damper  

SciTech Connect

Ecolaire Corp. has designed, fabricated and installed a new type of isolation damper which provides alternatives to customary new power plant design and upgrades. Through the combined efforts of two experienced product groups, Ecolaire Corp. has successfully proved that a steam turbine can be isolated from the main condenser without taking the condenser out of service or requiring auxiliary condensing equipment. Ecolaire Heat Transfer, an international supplier of steam surface condensers, and Mosser Damper, supplier of flue gas dampers for wet flue gas desulfurization applications and other harsh environments have combined their technologies and field experiences to develop a guillotine damper which allows personnel to access the interior of the steam turbine while the main condenser continues to operate. The cooperation between product groups was critical in achieving a design for the application which addresses the varying equipment arrangements and operating conditions.

Fehnel, G.N.; Finelli, P.M. [Ecolaire Corp., Easton, PA (United States)

1994-12-31

275

The Role of Social Isolation in Suicide.  

ERIC Educational Resources Information Center

Reviews the literature which relates to the role of social isolation in suicide. Major areas reviewed include theories on suicide and social isolation, measures of social isolation, and empirical studies which concern the relationship of social isolation to suicide. (Author)

Trout, Deborah L.

1980-01-01

276

Genetics Home Reference: Isolated growth hormone deficiency  

MedlinePLUS

... definitions Reviewed February 2012 What is isolated growth hormone deficiency? Isolated growth hormone deficiency is a condition ... against infection (agammaglobulinemia). How common is isolated growth hormone deficiency? The incidence of isolated growth hormone deficiency ...

277

Stiffness controllable isolation system for near-fault seismic isolation  

Microsoft Academic Search

A seismic structure isolated by a conventional passive isolation system is usually a long-period structural system with a fixed fundamental vibration frequency. Even though conventional isolation systems may effectively mitigate the dynamic responses of structures in a regular earthquake, they may also encounter a low-frequency resonance problem when subjected to a near-fault earthquake that usually has a long-period pulse-like waveform.

Lyan-Ywan Lu; Ging-Long Lin; Tzu-Ching Kuo

2008-01-01

278

Isolated resonator gyroscope with isolation trimming using a secondary element  

NASA Technical Reports Server (NTRS)

The present invention discloses a resonator gyroscope including an isolated resonator. One or more flexures support the isolated resonator and a baseplate is affixed to the resonator by the flexures. Drive and sense elements are affixed to the baseplate and used to excite the resonator and sense movement of the gyroscope. In addition, at least one secondary element (e.g., another electrode) is affixed to the baseplate and used for trimming isolation of the resonator. The resonator operates such that it transfers substantially no net momentum to the baseplate when the resonator is excited. Typically, the isolated resonator comprises a proof mass and a counterbalancing plate.

Challoner, A. Dorian (Inventor); Shcheglov, Kirill V. (Inventor)

2006-01-01

279

Dim Isolated Neutron Stars, Cooling and Energy Dissipation  

E-print Network

The cooling and reheating histories of dim isolated neutron stars(DINs) are discussed. Energy dissipation due to dipole spindown with ordinary and magnetar fields, and due to torques from a fallback disk are considered as alternative sources of reheating which would set the temperature of the neutron star after the initial cooling era. Cooling or thermal ages are related to the numbers and formation rates of the DINs and therefore to their relations with other isolated neutron star populations. Interaction with a fallback disk, higher multipole fields and activity of the neutron star are briefly discussed.

M. Ali Alpar

2006-09-07

280

Genetic characterization of Mycobacterium avium isolates recovered from humans and animals in Australia.  

PubMed Central

Genetic relationships amongst 115 mainly Australian isolates of Mycobacterium avium were assessed using multilocus enzyme electrophoresis (MEE). The isolates were divided into 58 electrophoretic types (ETs), with a mean genetic diversity of 0.29. Isolates from humans were closely related to but distinct from those cultured from birds, whilst some porcine isolates belonged to the same ETs as certain human isolates. Pulsed field gel electrophoresis (PFGE) was used to differentiate related isolates, and those from birds and some from other animals, including pigs, were distinguished from the human isolates. The results of MEE and PFGE suggested that certain strains of M. avium may be transmitted between birds and pigs, but there was no clear evidence of transmission to humans. The serovar of the M. avium isolates was not obviously related to their ET assignment or their PFGE type. Images Fig. 2 PMID:8626003

Feizabadi, M. M.; Robertson, I. D.; Cousins, D. V.; Dawson, D.; Chew, W.; Gilbert, G. L.; Hampson, D. J.

1996-01-01

281

Material isolation enclosure  

SciTech Connect

This invention is comprised of an enclosure similar to a glovebox for isolating materials from the atmosphere, yet allowing a technician to manipulate the materials and also apparatus which is located inside the enclosure. A portion of a wall of the enclosure is comprised of at least one flexible curtain. An opening defined by a frame is provided for the technician to insert his hands and forearms into the enclosure. The frame is movable in one plane, so that the technician has access to substantially all of the working interior of the enclosure. As the frame is moved by the technician, while he accomplishes work inside the enclosure, the curtain moves such that the only opening through the enclosure wall is the frame. In a preferred embodiment, where a negative pressure is maintained inside the enclosure, the frame is comprised of airfoils so that turbulence is reduced, thereby enhancing material retention within the box.

Martell, C.J.; Dahlby, J.W.; Gallimore, B.F.; Comer, B.E.; Stone, W.A.; Carlson, D.O.

1991-03-12

282

Field Experiences  

NSDL National Science Digital Library

Field observations and field experiences have traditionally been at the core of geoscience instruction. This session was designed to allow the entire GSA community to come together to share and discuss both traditional and emerging roles of field experiences in teaching geosciences. This site provides a searchable collection of posters about field experiences from a session at the 2004 GSA annual meeting.

283

Isolation Procedures for Farrowing Operations  

E-print Network

to be the acclimatization period of isolation. These ?natural vaccination? and ?sentinel animal? techniques are effective methods for stimulating immunity in replacement animals against disease-causing microorganisms in the herd. If a ?sentinel? cull animal gets sick... breeding swine is to prevent the herd from being exposed to new disease-causing organisms. During the isolation period, keep feed and water free of antibacterial agents to avoid ?covering up? signs of disease. If breed- ing swine in isolation become sick...

Lawhorn, D. Bruce

2002-01-31

284

Dissemination of clonal Salmonella enterica serovar Typhimurium isolates causing salmonellosis in Mauritius.  

PubMed

Salmonella enterica serotype Typhimurium is one of the leading causes of salmonellosis in Mauritius, where it has also been associated with outbreaks of foodborne illness. However, little is known about its molecular epidemiology in the country. This study was therefore undertaken to investigate the clonality and source of Salmonella Typhimurium in Mauritius by studying human, food, and poultry isolates by pulsed-field gel electrophoresis (PFGE) and antibiotic minimum inhibitory concentration determination. Forty-nine isolates collected between 2008 and 2011 were analyzed, including 25 stool isolates from foodborne illness outbreaks and sporadic gastroenteritis cases, four blood isolates, one postmortem colon isolate, 14 food isolates, and five poultry isolates. All isolates were pansusceptible to the 16 antibiotics tested, except for two isolates that were resistant to sulfamethoxazole and trimethoprim. Overall characterization of the isolates by PFGE digested with XbaI and BlnI resulted in eight different patterns. The largest of the clusters in the composite dataset consisted of 20 isolates, including two raw chicken isolates, four poultry isolates, and nine human stool isolates from two outbreaks. A second cluster consisted of 18 isolates, of which 12 originated from human blood and stool samples from both sporadic and outbreak cases. Six food isolates were also found in this cluster, including isolates from raw and grilled chicken, marlin mousse, and cooked pork. One poultry isolate had a closely related PFGE pattern. The results indicate that one clone of Salmonella Typhimurium found in poultry has been causing outbreaks of foodborne illness in Mauritius and another clone that has caused many cases of gastrointestinal illness and bacteremia in humans could also be linked to poultry. Thus, poultry appears to be a major reservoir for Salmonella Typhimurium in Mauritius. Initiating on-farm control strategies and measures against future dissemination may substantially reduce the number of cases of salmonellosis in the country. PMID:23705985

Issack, Mohammad I; Garcia-Migura, Lourdes; Ramsamy, Veemala D; Svendsen, Christina A; Pornruangwong, Srirat; Pulsrikarn, Chaiwat; Hendriksen, Rene S

2013-07-01

285

Clinical Isolates of Streptococcus pneumoniae with Different Susceptibilities to Ceftriaxone and Cefotaxime  

PubMed Central

Ceftriaxone and cefotaxime are extended-spectrum cephalosporins previously demonstrated to possess very similar in vitro activities against Streptococcus pneumoniae. Anecdotal reports of isolates with divergent in vitro susceptibilities to ceftriaxone and cefotaxime have been published. To determine the prevalence of pneumococcal isolates with divergent ceftriaxone and cefotaxime susceptibilities, we tested 1,000 clinical isolates collected by U.S. laboratories in 2001-2002 by broth microdilution and E-test. The percentages of isolates susceptible to ceftriaxone and cefotaxime were significantly different by both broth microdilution (98.6 and 96.6%, respectively; P < 0.05) and E-test (98.3 and 95.8%; P < 0.001). The differences observed were due solely to the activities of the two agents against penicillin-resistant isolates. Twenty-six of 188 penicillin-resistant isolates (13.8%) demonstrated different ceftriaxone and cefotaxime MIC interpretative phenotypes when tested by broth microdilution; 18 isolates were concurrently ceftriaxone susceptible and cefotaxime intermediate, 6 were ceftriaxone intermediate and cefotaxime resistant, and 2 were ceftriaxone susceptible and cefotaxime resistant (1.1% of penicillin-resistant isolates; 0.2% of all isolates tested). Sixteen of the 26 isolates (65%) were from southern U.S. states. The 26 isolates had serogroups and serotypes (6, 9, 14, 19, and 23) commonly associated with penicillin-resistant isolates; SmaI pulsed-field gel electrophoresis identified 18 isolates (69%) dispersed among five subtype groups and 8 isolates that were unrelated to any of the other isolates. We conclude that certain isolates of penicillin-resistant pneumococci are less susceptible to cefotaxime than to ceftriaxone and that these isolates are not the result of the spread of a single clone. Whether such isolates have increased in prevalence over time remains unknown. PMID:14506024

Karlowsky, James A.; Jones, Mark E.; Draghi, Deborah C.; Sahm, Daniel F.

2003-01-01

286

Isolation and confinement - Considerations for colonization  

NASA Technical Reports Server (NTRS)

This paper discusses three types of isolation (sensory/perceptual, temporal, and social) that could adversely affect mankind in space. The literature dealing with laboratory and field experiments relevant to these areas is summarized and suggestions are given for dealing with these problems within the space colony community. Also, consideration is given to the potential effects of physical confinement and the need for usable space. Finally, a modification of Maslow's hierarchy of needs is proposed as a theoretical framework to understand and investigate mankind's psychological needs in space.

Akins, F. R.

1978-01-01

287

Help for the Isolated Physics Teacher  

NASA Astrophysics Data System (ADS)

The feeling of professional loneliness that comes from being the only physics teacher in a school is one of the many reasons new physics teachers choose to leave the field. This interactive discussion will detail some of the ways that our institutions and we as individuals can provide meaningful support for isolated physics teachers. We will share ideas, including physics-based student challenges/competitions and regular local meetings of a local Physics Teacher Alliance, that provide opportunities for teachers to share experiences, test new lesson ideas, and simply spend more time with people who understand the punchline to a geeky joke.

Gelderman, Richard; Selway, James

2012-02-01

288

Porcine Epidemic Diarrhea Virus RNA Present in Commercial Spray-Dried Porcine Plasma Is Not Infectious to Na?ve Pigs  

PubMed Central

Porcine epidemic diarrhea virus emerged in North America in April 2013 and has since been identified in 30 U.S. States, Canada and Mexico. The rapid spread of PEDV has raised concerns about the role of feed and particularly pork-by-product components such as spray-dried porcine plasma (SDPP) in PEDV transmission. The aim of this study was to determine the infectivity of PEDV RNA present in commercial SDPP. Specifically, 40 3-week-old PEDV naïve pigs were randomly assigned to one of five treatment groups. At day post inoculation (dpi) 0, NEG-CONTROL pigs were sham-inoculated, PEDV-CONTROL pigs received cell culture propagated PEDV, and SDPP-CONTROL pigs were switched to a diet with 5% SDPP containing 5.1±0.1 log10 PEDV RNA copies/g. To evaluate a potential positive effect of anti-PEDV antibodies in SDPP on PEDV challenge, four days prior to PEDV challenge the pigs in the SDPP-PEDV group were switched to and remained on a 5% SDPP diet through dpi 28. Another group, EGG-PEDV, was orally administered a commercial egg-derived liquid PEDV globulin product from dpi -4 through 6. All PEDV-CONTROL pigs began shedding PEDV in feces by dpi 3 and seroconverted between dpi 7 and 14, whereas pigs in NEG-CONTROL and SDPP-CONTROL groups remained PEDV RNA negative and did not seroconvert to PEDV for the study duration. This indicates no evidence of infectivity of the PEDV RNA in the SDPP lot utilized. Furthermore, under the study conditions SDPP or egg-derived liquid PEDV globulin addition did not significantly alter PEDV-shedding or overall disease course after experimental challenge. PMID:25116479

Opriessnig, Tanja; Xiao, Chao-Ting; Gerber, Priscilla F.; Zhang, Jianqiang; Halbur, Patrick G.

2014-01-01

289

Field-tunable probe for combined electric and magnetic field measurements  

Microsoft Academic Search

A method to measure the magnitude and phase of electric and magnetic fields with a single probe is presented. The optically-based probe, consisting of a hybrid combination of gallium arsenide followed by terbium gallium garnet, employs the Pockels effect to measure electric fields and the Faraday effect to measure magnetic fields. Isolation between the two effects is achieved via external

Ronald M. Reano; John F. Whitaker; Linda P. B. Katehi

2002-01-01

290

Associations between the Genotypes of Staphylococcus aureus Bloodstream Isolates and Clinical Characteristics and Outcomes of Bacteremic Patients  

Microsoft Academic Search

We investigated associations between the genotypic and phenotypic features of Staphylococcus aureus blood- stream isolates and the clinical characteristics of bacteremic patients enrolled in a phase III trial of S. aureus bacteremia and endocarditis. Isolates underwent pulsed-field gel electrophoresis, PCR for 33 putative virulence genes, and screening for heteroresistant glycopeptide intermediate S. aureus (hGISA). A total of 230 isolates (141

Tahaniyat Lalani; Jerome J. Federspiel; Helen W. Boucher; Thomas H. Rude; In-Gyu Bae; Michael J. Rybak; Giang T. Tonthat; G. Ralph Corey; Martin E. Stryjewski; George Sakoulas; Vivian H. Chu; Jeff Alder; Judith N. Steenbergen; Steven A. Luperchio; Marilyn Campion; Christopher W. Woods; Vance G. Fowler

291

Methicillin-Resistant Staphylococcus saprophyticus Isolates Carrying Staphylococcal Cassette Chromosome mec Have Emerged in Urogenital Tract Infections  

Microsoft Academic Search

Staphylococcus saprophyticus is a uropathogenic bacterium that causes acute uncomplicated urinary tract infections, particularly in female outpatients. We investigated the dissemination and antimicrobial suscepti- bilities of 101 S. saprophyticus isolates from the genitourinary tracts of patients in Japan. Eight of these isolates were mecA positive and showed -lactam resistance. Pulsed-field gel electrophoresis showed that only some isolates were isogenic, indicating

Masato Higashide; Makoto Kuroda; C. T. N. Omura; M. Kumano; S. Ohkawa; S. Ichimura; T. Ohta

2008-01-01

292

Oropouche virus isolation, southeast Brazil.  

PubMed

An Oropouche virus strain was isolated from a novel host (Callithrix sp.) in Arinos, Minas Gerais State, southeastern Brazil. The virus was identified by complement fixation test and confirmed by reverse transcription-polymerase chain reaction. Phylogenetic analysis identified this strain as a genotype III isolate previously recognized only in Panama. PMID:16318707

Nunes, Márcio Roberto Teixeira; Martins, Lívia Carício; Rodrigues, Sueli Guerreiro; Chiang, Jannifer Oliveira; Azevedo, Raimunda do Socorro da Silva; da Rosa, Amelia P A Travassos; Vasconcelos, Pedro Fernando da Costa

2005-10-01

293

Characterization of Borrelia lusitaniae Isolates Collected in Tunisia and Morocco  

PubMed Central

Borrelia lusitaniae is a species within the complex Borrelia burgdorferi sensu lato and is infrequently isolated in Europe. In contrast, this species is by far the most predominant in North Africa and in Portugal. In this study, we analyzed the genetic diversity, at several loci, of a large population of isolates from free-living Ixodes ricinus ticks collected in Tunisia and Morocco. We found a moderate diversity of the whole genome by using pulsed-field gel electrophoresis as well as in the ospA gene sequences, compared to a high level of strain homogeneity in the small noncoding ribosomal spacer. In contrast, a high diversity of this locus has been previously reported for Portuguese isolates. We hypothesize that B. lusitaniae strains isolated in North Africa constitute a clone of Portuguese origin. PMID:15814970

Younsi, Hend; Sarih, M'Hammed; Jouda, Fatima; Godfroid, Edmond; Gern, Lise; Bouattour, Ali; Baranton, Guy; Postic, Daniele

2005-01-01

294

[Molecular comparison of Legionella pneumophila serogroup 1 isolated in Tunisia].  

PubMed

Legionella pneumophila is a common cause of hospital and community-acquired pneumonia, being transmitted by inhalation of aqueous aerosols. Most outbreaks are linked to contaminated hot water systems and cooling towers. Our study was about the molecular typing of 35 strains of L. pneumophila including four clinical isolates and 31 environmental strains isolated from the distribution systems of 14 hotels. Among the clinical strains, two have the same pattern, however, all were different from the studied environmental strains. For the 31 environmental strains, ten patterns were obtained. Among which, a same pulsotype was found for four strains isolated from four different establishments. In addition, two different pulsotypes were found for strains isolated from the same establishment. The pulsed-field gel electrophoresis showed the existence of various patterns. Although cases of legionellosis were declared in these hotels, there are no epidemiological links between the clinical and environmental strains. PMID:18191502

Mehiri-Zghal, E; Essalah, L; Ghariani, A; Mahjoubi, W; Reyrolle, M; Meugnier, H; Forey, F; Jarraud, S; Freney, J; Etienne, J; Slim-Saidi, L

2008-07-01

295

Salmonella enterica isolated from wildlife at two Ohio rehabilitation centers.  

PubMed

Between May and September 2004, fecal samples from various wildlife species admitted to two rehabilitation centers in Ohio were cultured for Salmonella enterica and Escherichia coli O157:H7. Eight of 71 (11%) samples, including specimens from three opossums (Didelphis virginiana), two gray squirrels (Sciurus carolinensis), a woodchuck (Marmota monax), a Harris hawk (Parabuteo unicinctus), and a screech owl (Otus asio) tested positive for Salmonella serovars Braenderup, Senftenberg, Oranienburg, and Kentucky. The Salmonella Oranienburg isolates were indistinguishable by pulsed-field gel electrophoresis. Most isolates were susceptible to commonly used antibiotics; however, the Salmonella Kentucky isolate was resistant to multiple beta-lactam antibiotics (amoxicillin/clavulanic acid and ampicillin), cefoxitin, and ceftiofur, a third-generation cephalosporin. Escherichia coli O157:H7 was not isolated from any sample. Transmission of Salmonella from wildlife may occur between animals at rehabilitation centers. PMID:17939349

Jijón, Steffani; Wetzel, Amy; LeJeune, Jeffrey

2007-09-01

296

ISOLATION OF EPIDERMAL DESMOSOMES  

PubMed Central

A method is reported for the isolation of desmosomes in a high yield and of a purity suitable for biochemical analysis. The procedure utilizes the selective solubilizing action of citric acid-sodium citrate (CASC) buffer, pH 2.6, on the non-cornified layers of cow nose epidermis, followed by discontinuous sucrose density gradient centrifugation. Electron microscopy with both thin sections of pellets and unfixed spread preparations reveals that after centrifugation, desmosomes are located mainly at the 55–60% sucrose interface. In the desmosome preparation thus obtained, the characteristic desmosome structure is well preserved, showing the midline, unit membranes, and dense plaques. Furthermore, removal of the epidermal filament bundles by the solubilizing action of CASC buffer has revealed a finely filamentous layer on the cytoplasmic surface of the plaques. The dimensions, location, and appearance of this layer correspond with those of the "connecting component" which has been previously suggested as being responsible for the attachment of epidermal filament bundles to the desmosome. PMID:4138144

Skerrow, Christine J.; Matoltsy, A. Gedeon

1974-01-01

297

New ventilated isolation cage.  

PubMed

A multifunction lid has been developed for a commercially available transparent animal cage which permits feeding, watering, viewing, long-term holding, and local transport of laboratory rodents on experiment while isolating the surrounding environment. The cage is airtight except for its inlet and exhaust high-efficiency particulate air filters, and it is completely steam-sterilizable. Opening of the cage's feed and water ports causes an inrush of high velocity air which prevents back-migration of aerosols and permits feeding and watering while eliminating need for chemical vapor decontamination. Ventilation system design permits the holding in adjacent cages of animals infected with different organisms without danger of cross-contamination; leaves the animal room odor-free; reduces required bedding changes to twice a month or less, and provides investigators with capability to control precisely individual cage ventilation rates. Forty-eight cages can be conveniently placed on a standard NIH "shoebox" cage rack (60 inches wide x 28 inches deep x 74 inches high) fitted with a simple manifold exhaust system. The entire system is mobile, requiring only an electrical power outlet. Principal application of the caging system is in the area of preventing exposure of animal caretakers to pathogenic substances associated with the animal host, and in reducing handling of animals and their exposure to extraneous contamination. PMID:5659368

Cook, R O

1968-05-01

298

Spacetime near isolated and dynamical trapping horizons  

NASA Astrophysics Data System (ADS)

We study the near-horizon spacetime for isolated and dynamical trapping horizons (equivalently marginally outer trapped tubes). The metric is expanded relative to an ingoing Gaussian null coordinate and the terms of that expansion are explicitly calculated to second order. For the spacelike case, knowledge of the intrinsic and extrinsic geometry of the (dynamical) horizon is sufficient to determine the near-horizon spacetime, while for the null case (an isolated horizon) more information is needed. In both cases spacetime is allowed to be of arbitrary dimension and the formalism accommodates both general relativity as well as more general field equations. The formalism is demonstrated for two applications. First, spacetime is considered near an isolated horizon and the construction is both checked against the Kerr-Newman solution and compared to the well-known near-horizon limit for stationary extremal black hole spacetimes. Second, spacetime is examined in the vicinity of a slowly evolving horizon and it is demonstrated that there is always an event horizon candidate in this region. The geometry and other properties of this null surface match those of the slowly evolving horizon to leading order and in this approximation the candidate evolves in a locally determined way. This generalizes known results for Vaidya as well as certain spacetimes known from studies of the fluid-gravity correspondence.

Booth, Ivan

2013-01-01

299

Reactor core isolation cooling system  

DOEpatents

A reactor core isolation cooling system includes a reactor pressure vessel containing a reactor core, a drywell vessel, a containment vessel, and an isolation pool containing an isolation condenser. A turbine is operatively joined to the pressure vessel outlet steamline and powers a pump operatively joined to the pressure vessel feedwater line. In operation, steam from the pressure vessel powers the turbine which in turn powers the pump to pump makeup water from a pool to the feedwater line into the pressure vessel for maintaining water level over the reactor core. Steam discharged from the turbine is channeled to the isolation condenser and is condensed therein. The resulting heat is discharged into the isolation pool and vented to the atmosphere outside the containment vessel for removing heat therefrom. 1 figure.

Cooke, F.E.

1992-12-08

300

Multiple locus variable number tandem repeat analysis of Mycoplasma bovis isolated from local and imported cattle.  

PubMed

Mycoplasma bovis is an important and emerging pathogen of cattle. In this study, multiple locus variable number tandem repeat (VNTR) analysis was used to differentiate M. bovis type strain PG45 and 68 M. bovis field isolates, including 34 isolates from calves imported to Israel from Australia, Lithuania and Hungary in the period 2006-2011, 32 isolates from mastitic dairy cows in Israel in the period 2000-2011, one isolate from the pneumonic lungs of a calf in Israel in 2010 and one isolate from frozen bull semen in Israel in 2008. A total of 35 VNTR types were distinguished, including three, eight and 10 different VNTR types among isolates from calves imported from Australia, Hungary and Lithuania, respectively, and 17 VNTR types among isolates from dairy cows in Israel. The VNTR types in isolates from Lithuanian calves were not identified among isolates from Israeli dairy cows. VNTR type XX, present in the Hungarian group, was identified in one Israeli mastitis-associated isolate. A cluster of 16 M. bovis isolates from Israeli dairy cows possessed the same VNTR type III as three Australian isolates from a single shipment of calves in 2006. The other cluster of isolates contained M. bovis strain 883, isolated from a mastitic cow, strain 72236, isolated from a calf with pneumonia, two isolates from calves imported from Australia to the same farm 3 months previously and four isolates from calves in quarantine imported to Israel from Australia in 2009-2010. Multiple locus VNTR analysis is a useful tool for understanding the movement and spread of strains of M. bovis within and across international boundaries. PMID:23639372

Amram, Eytan; Freed, Mor; Khateb, Nihaya; Mikula, Inna; Blum, Shlomo; Spergser, Joachim; Sharir, Beny; Ozeri, Roni; Harrus, Shimon; Lysnyansky, Inna

2013-08-01

301

VARIABILITY IN VIRULENCE OF HETEROBASIDION ANNOSUM ISOLATES FROM PONDROSA AND JEFFREY PINE IN AREAS OF HIGH AND LOW PHOTOCHEMICAL AIR POLLUTION  

EPA Science Inventory

Virulence of Heterobasidion annosum isolates from different geographic locations throughout California was evaluated by inoculation of ponderosa pine trees in the field and seedlings in the greenhouse. Tests were designed to compare isolates obtained from areas of chronic photoch...

302

Isolated horizons in higher dimensional Einstein Gauss Bonnet gravity  

Microsoft Academic Search

The isolated horizon framework was introduced in order to provide a local description of black holes that are in equilibrium with their (possibly dynamic) environment. Over the past several years, the framework has been extended to include matter fields (dilaton, Yang Mills etc) in D = 4 dimensions and cosmological constant in D >= 3 dimensions. In this paper, we

Tomás Liko; Ivan Booth

2007-01-01

303

Isolation and Characterization of Cytotoxic, Aggregative Citrobacter freundii  

Microsoft Academic Search

Citrobacter freundii is an infrequent but established cause of diarrhea in humans. However, little is known of its genetic diversity and potential for virulence. We analyzed 26 isolates, including 12 from human diarrheal patients, 2 from human fecal samples of unknown diarrheal status, and 12 from animals, insects, and other sources. Pulsed field gel electrophoresis using XbaI allowed us to

Li Bai; Shengli Xia; Ruiting Lan; Liyun Liu; Changyun Ye; Yiting Wang; Dong Jin; Zhigang Cui; Huaiqi Jing; Yanwen Xiong; Xuemei Bai; Hui Sun; Jin Zhang; Lei Wang; Jianguo Xu

2012-01-01

304

Successive Emergence of Extended-Spectrum  -Lactamase-Producing and Carbapenemase-Producing Enterobacter aerogenes Isolates in a University Hospital  

Microsoft Academic Search

Sixty-two clinical isolates of Enterobacter aerogenes resistant to expanded-spectrum cephalosporins were collected between July 2003 and May 2005. Among these isolates, 23 (37.1%) were imipenem (IPM) susceptible, and 39 (62.9%) were IPM insusceptible, of which 89.7% (35\\/39) were resistant and 10.3% (4\\/39) were inter- mediate. Isolate genotypes were compared by pulsed-field gel electrophoresis. Of 62 isolates, 48 belonged to epidemic

M. Biendo; B. Canarelli; D. Thomas; F. Rousseau; F. Hamdad; C. Adjide; G. Laurans; F. Eb

2008-01-01

305

Phylogenetic analysis of trichloroethylene-degrading bacteria newly isolated from soil polluted with this contaminant  

Microsoft Academic Search

Five methanotrophs (strains 18-2, EB1, KSWIII, KSPIII and KSPIII) and three aromatic compound oxidizers (strains KP22, KP24 and KT1) were isolated from the natural field polluted with trichloroethylene (TCE). Phylogenetic analysis based on 16S rRNA gene sequence suggested that all of the isolates belonged to the class Proteobacteria. Two of the methanotrophic isolates, strains 18-2 and EB1, were closely related

Satoshi Hanada; Toru Shigematsu; Katsutoshi Shibuya; Masahiro Eguchi; Takeshi Hasegawa; Fusako Suda; Yoichi Kamagata; Takahiro Kanagawa; Ryuichiro Kurane

1998-01-01

306

Isolation and Physiology of Bacteria from Contaminated Subsurface Sediments? †  

PubMed Central

The majority of environmental microorganisms cannot be grown by traditional techniques. Here we employed, and contrasted with conventional plating, an alternative approach based on cultivation of microorganisms inside diffusion chambers incubated within natural samples, followed by subculturing in petri dishes. Using this approach, we isolated microorganisms from subsurface sediments from the Field Research Center (FRC) in Oak Ridge, TN. The sediments were acidic and highly contaminated with uranium, heavy metals, nitrate, and organic pollutants. Phylogenetic analysis of 16S rRNA gene sequences revealed clear differences between diversity of isolates obtained by the diffusion chamber approach and those obtained by conventional plating. The latter approach led to isolation of members of the Alpha- and Gammaproteobacteria, Actinobacteria, and Verrucomicrobia. Isolates obtained via the diffusion chamber approach represented the Alpha-, Beta-, and Gammaproteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes. Notably, one-third of the isolates obtained by the new method were closely related to species known from previous molecular surveys conducted in the FRC area. Since the initial growth of microorganisms inside diffusion chambers occurred in the presence of the environmental stress factors, we expected the isolates we obtained to be tolerant of these factors. We investigated the physiologies of selected isolates and discovered that the majority were indeed capable of growth under low pH and/or high concentrations of heavy metals and nitrate. This indicated that in contrast to conventional isolation, the diffusion chamber-based approach leads to isolation of species that are novel, exhibit tolerance to extant environmental conditions, and match some of the species previously discovered by molecular methods. PMID:20870785

Bollmann, Annette; Palumbo, Anthony V.; Lewis, Kim; Epstein, Slava S.

2010-01-01

307

Characterization of Newcastle disease virus isolated from northern pintail (Anas acuta) in Japan.  

PubMed

A field isolate of Newcastle disease virus (NDV) isolated from northern pintail (Anas acuta) in Tohoku district, northeast Japan, was characterized. Phylogenetic analysis of the fusion protein indicated that the isolate belonged to genotype I and was closely related to isolates from the Far East corresponded to the migration route for this bird species. The isolate had the typical avirulent cleavage site of the fusion protein (112)GKQGR*L(117). In addition, pathogenicity tests indicated the isolate to have avirulent characteristics. However, the isolate has been shown to cause fusion cytopathic effects and form plaques on chicken embryo fibroblasts (CEF) in the absence of trypsin. The present results suggest that the CEF-adapted NDV, which is avirulent, is circulating among waterfowl populations. PMID:18176032

Sakai, Kouji; Sakabe, Genki; Tani, Orie; Watanabe, Yuko; Jahangir, Alam; Nakamura, Masayuki; Takehara, Kazuaki

2007-12-01

308

Essential points of conformal vector fields  

NASA Astrophysics Data System (ADS)

An essential point of a conformal vector field ? on a conformal manifold (M,c) is a point around which the local flow of ? preserves no metric in the conformal class c. It is well-known that a conformal vector field vanishes at each essential point. In this note we show that essential points are isolated. This is a generalization to higher dimensions of the fact that the zeros of a holomorphic function are isolated. As an application, we show that every connected component of the zero set of a conformal vector field is totally umbilical.

Belgun, Florin; Moroianu, Andrei; Ornea, Liviu

2011-03-01

309

Bacillus pumilus SAFR-032 isolate  

NASA Technical Reports Server (NTRS)

The present invention relates to discovery and isolation of a biologically pure culture of a Bacillus pumilus SAFR-032 isolate with UV sterilization resistant properties. This novel strain has been characterized on the basis of phenotypic traits, 16S rDNA sequence analysis and DNA-DNA hybridization. According to the results of these analyses, this strain belongs to the genus Bacillus. The GenBank accession number for the 16S rDNA sequence of the Bacillus pumilus SAFR-032 isolate is AY167879.

Venkateswaran, Kasthuri J. (Inventor)

2007-01-01

310

Relationship between the Original Multiply Resistant South African Isolates of Streptococcus pneumoniae from 1977 to 1978 and Contemporary International Resistant Clones  

Microsoft Academic Search

High-level penicillin G-resistant as well as multidrug-resistant Streptococcus pneumoniae isolates were first described in South Africa in 1977. The relationship between these original multidrug-resistant South African isolates and other resistant clones was investigated. Twenty-six representative isolates isolated from initial outbreaks in South Africa from 1977 to 1978 were characterized by multilocus sequence typing and pulsed-field gel electrophoresis. Twenty-one isolates were

Ralf ReneReinert; Michael R. Jacobs; Peter C. Appelbaum; Saralee Bajaksouzian; Soraia Cordeiro; Mark van der Linden; Adnan Al-Lahham

2005-01-01

311

Paramyxovirus type 1 infections of racing pigeons: 1 characterisation of isolated viruses  

Microsoft Academic Search

Viruses isolated from field outbreaks of disease in racing pigeons in continental Europe and Great Britain were shown to be identical by serological tests using conventional chicken antisera and mouse monoclonal antibodies. The pigeon viruses showed high levels of cross-reaction to Newcastle disease virus (NDV) in haemagglutination inhibition tests and Madin-Darby bovine kidney cells infected with pigeon virus isolates bound

DJ Alexander; PH Russell

1984-01-01

312

Pathogenic variation among isolates of Pyricularia oryzae affecting rice, wheat, and grasses in Brazil  

Microsoft Academic Search

Rice blast caused by Pyricularia oryzae occurs on wheat under natural field conditions in Brazil. Isolates of P. oryzae collected from rice, wheat and grass weeds Digitaria sanguinalis, Rhynchelytrum roseum, Pennisetum setosum and Eleusine indica were tested for virulence to 30 rice, five wheat and one barley cultivars. All isolates from rice, wheat and grass weeds were pathogenic to the

A. S. Prabhu; M. C. Filippi; N. Castro

1992-01-01

313

Helicopter gearbox isolation using periodically layered fluidic isolators  

NASA Astrophysics Data System (ADS)

In rotorcraft transmissions, vibration generation by meshing gear pairs is a significant source of vibration and cabin noise. This high-frequency gearbox noise is primarily transmitted to the fuselage through rigid connections, which do not appreciably attenuate vibratory energy. The high-frequency vibrations typically include discrete gear-meshing frequencies in the range of 500--2000 Hz, and are often considered irritating and can reduce pilot effectiveness and passenger comfort. Periodically-layered isolators were identified as potential passive attenuators of these high frequency vibrations. Layered isolators exhibit transmissibility "stop bands," or frequency ranges in which there is very low transmissibility. An axisymmetric model was developed to accurately predict the location of these stop bands for isolators in compression. A Ritz approximation method was used to model the axisymmetric elastic behavior of layered cylindrical isolators. This model of layered isolators was validated with experiments. The physical design constraints of the proposed helicopter gearbox isolators were then estimated. Namely, constraints associated with isolator mass, axial stiffness, geometry, and elastomeric fatigue were determined. The passive performance limits of layered isolators were then determined using a design optimization methodology employing a simulated annealing algorithm. The results suggest that layered isolators cannot always meet frequency targets given a certain set of design constraints. Many passive and active design enhancements were considered to address this problem, and the use of embedded inertial amplifiers was found to exhibit a combination of advantageous effects. The first benefit was a lowering of the beginning stop band frequency, and thus a widening of the original stop band. The second was a tuned absorber effect, where the elastomer layer stiffness and the amplified tuned mass combined to act as a vibration absorber within the stop band. The use of embedded fluid elements was identified as an efficient means of implementing inertial amplification. When elastomer layers are compressed quasi-statically, the actual measured axial stiffness is quite higher the than one-dimensional stiffness predicted on the basis of a Young's modulus. Because of this effect, layered isolators can be designed to accommodate the high axial stiffnesses required for helicopter gearbox supports, while also providing broadband high frequency attenuation.

Szefi, Joseph Thomas

2003-07-01

314

Flight representative positive isolation disconnect  

NASA Technical Reports Server (NTRS)

Resolutions were developed for each problem encountered and a tradeoff analysis was performed to select a final configuration for a flight representative PID (Positive Isolation Disconnect) that is reduced in size and comparable in weight and pressure drop to the developmental PID. A 6.35 mm (1/4-inch) line size PID was fabricated and tested. The flight representative PID consists of two coupled disconnect halves, each capable of fluid isolation with essentially zero clearance between them for zero leakage upon disconnect half disengagement. An interlocking foolproofing technique prevents uncoupling of disconnect halves prior to fluid isolation. Future development efforts for the Space Shuttle subsystems that would benefit from the use of the positive isolation disconnect are also recommended. Customary units were utilized for principal measurements and calculations with conversion factors being inserted in equations to convert the results to the international system of units.

Rosener, A. A.; Jonkoniec, T. G.

1977-01-01

315

Study of base isolation systems  

E-print Network

The primary objective of this investigation is to outline the relevant issues concerning the conceptual design of base isolated structures. A 90 feet high, 6 stories tall, moment steel frame structure with tension cross ...

Manarbek, Saruar

2013-01-01

316

Genetics Home Reference: Isolated hyperchlorhidrosis  

MedlinePLUS

... molecule (bicarbonate ion) and a positively charged hydrogen atom (known as a proton). The presence of protons ... glossary definitions help with understanding isolated hyperchlorhidrosis? acidity ; atom ; autosomal ; autosomal recessive ; bicarbonate ; Ca ; cell ; chloride ; dehydration ; ...

317

Isolation of Lignocellulose Transforming Microbes.  

National Technical Information Service (NTIS)

Research demonstrated that a Basidiomycete fungus, Irpex lacteus, isolated from active galleries of the beetle Xyloterinus politus in Quercus (oak) trees, degraded approximately five times as much lignin from the standard hardwood substrate, No. 002 wood,...

D. M. Norris

1980-01-01

318

Isolated Singularities and Series Expansions  

NSDL National Science Digital Library

Using Maple or Mathmatica, learner should be able to experiment with Taylor and Laurent series commands in a computer algebra system and to explore the behavior of differentiable functions near isolated singularities.

Smith, David

2002-01-12

319

GONOCOCCAL SURVEILLANCE ISOLATE PROJECT (GSIP)  

EPA Science Inventory

The Gonococcal Isolate Surveillance Project (GISP) is a collaborative project to monitor antimicrobial resistance in Neisseria gonorrhoeae in the United States. The database is a sentinel surveillance system of 26 clinics for sexually transmitted diseases (STDs) and 5 regional la...

320

A fundamental oscillatory state of isolated rodent hippocampus  

PubMed Central

Population neuronal rhythms of various frequencies are observed in the rodent hippocampus during distinct behavioural states. However, the question of whether the hippocampus exhibits properties of spontaneous rhythms and population synchrony in isolation has not been definitively answered. To address this, we developed a novel preparation for studying neuronal rhythms in a relatively large hippocampal tissue in vitro. We isolated the whole hippocampus from mice up to 28 days postnatal age, removing the dentate gyrus while preserving the functional CA3-to-CA1 connections. Placing the hippocampal isolate in a perfusion chamber for electrophysiological assessment extracellular recordings from the CA1 revealed rhythmic field potential of 0.5 to ? 4 Hz that occurred spontaneously and propagated along the ventro-dorsal hippocampal axis. We provide convergent evidence, via measurements of extracellular pH and K+, recordings of synaptic and intracellular activities and morphological assessments, verifying that these rhythms were not the consequence of hypoxia. Data obtained via simultaneous extracellular and patch clamp recordings suggest that the spontaneous rhythms represent a summation of GABAergic IPSPs originating from pyramidal neurons, which result from synchronous discharges of GABAergic inhibitory interneurons. Similar spontaneous field rhythms were also observed in the hippocampal isolate prepared from young gerbils and rats. Based on these data, we postulate that the spontaneous rhythms represent a fundamental oscillatory state of the hippocampal circuitry isolated from extra-hippocampal inputs. PMID:11956340

Wu, Chiping; Shen, Hui; Luk, Wah Ping; Zhang, Liang

2002-01-01

321

Isolated sphenoidal sinusitis in children  

Microsoft Academic Search

Acute isolated infectious sphenoiditis is an uncommon, potentially dangerous condition which is often misdiagnosed because\\u000a of its nonspecific symptoms and paucity of clinical signs. We present eight children with isolated sphenoiditis who were managed\\u000a in our medical centre during the last 2 years and review the literature. All the patients were adolescents or pre-adolescents\\u000a and all experienced moderate to severe

Y. Haimi-Cohen; J. Amir; A. Zeharia; Y. Danziger; N. Ziv; M. Mimouni

1999-01-01

322

Isolation of ambient aerosols of known critical supersaturation: the differential critical supersaturation separator (DSCS)  

E-print Network

A field-deployable instrument has been developed that isolates from an ambient aerosol population only those particles that have critical supersaturations, Sc, within a narrow, user-specified, range. This Differential Critical Supersaturation...

Osborn, Robert John

2007-09-17

323

Genetic diversity of Brucella abortus isolates as determined by amplified fragment length polymorphism (AFLP) analysis  

E-print Network

with the powerful Bionumerics software package to determine the genetic relationships between B. abortus field isolates, collected from infections in wild herds of elk and bison to achieve a better understanding of the molecular diversity and evolution of B. abortus...

Bliss, Katherine Ann

2013-02-22

324

A magnetic non-reciprocal isolator for broadband terahertz operation  

PubMed Central

A Faraday isolator is an electromagnetic non-reciprocal device, a key element in photonics. It is required to shield electromagnetic sources against the effect of back-reflected light, as well as to limit the detrimental effect of back-propagating spontaneous emissions. A common isolator variant, the circulator, is widely used to obtain a complete separation between forward- and backward-propagating waves, thus enabling the realization of a desired transfer function in reflection only. Here we demonstrate a non-reciprocal terahertz Faraday isolator, operating on a bandwidth exceeding one decade of frequency, a necessary requirement to achieve isolation with the (few-cycle) pulses generated by broadband sources. The exploited medium allows a broadband rotation, up to 194°/T, obtained using a SrFe12O19 terahertz-transparent permanent magnet. This in turn enables the design of a stand-alone complete terahertz isolator without resorting to an external magnetic field bias, as opposed to all the optical isolators realized so far. PMID:23463001

Shalaby, Mostafa; Peccianti, Marco; Ozturk, Yavuz; Morandotti, Roberto

2013-01-01

325

Passive vibration isolation using a Roberts linkage  

NASA Astrophysics Data System (ADS)

The article present an ultralow frequency passive vibration isolation device as part of the preisolation stage for the Australian International Gravitational Observatory (AIGO). This isolator is based on the Roberts linkage and simulates a very long radius conical pendulum to provide two-dimensional isolation. It is designed as the second horizontal isolation component of the preisolator and it will support the remaining four isolation stages of the AIGO vibration isolator chain. A description of the device together with a theoretical model and its measured isolation performance are presented. With the current setup, we obtained 32 dB of isolation at 1 Hz.

Garoi, F.; Winterflood, J.; Ju, L.; Jacob, J.; Blair, D. G.

2003-07-01

326

Diversity of endophytic fungi isolated from korean ginseng leaves.  

PubMed

We investigated the diversity of the foliar endophytes of Korean ginseng. Endophytic fungi were isolated from healthy leaves of mountain-cultivated ginseng (MCG) and field-cultivated ginseng (FCG) at 4 sites in Chungbuk Province. A total of 24 species of fungal endophytes were identified using molecular approaches. Additionally, the diversity of these endophytic fungi was compared between MCG and FCG. The major isolated endophytes were Edenia gomezpompae and Gibberella moniliformis in the MCG and FCG samples, respectively. The results suggest that ginseng endophytes have different community structures in different environments, and this understanding may prove useful in ginseng cultivation. PMID:25071383

Eo, Ju-Kyeong; Choi, Min-Seok; Eom, Ahn-Heum

2014-06-01

327

Diversity of Endophytic Fungi Isolated from Korean Ginseng Leaves  

PubMed Central

We investigated the diversity of the foliar endophytes of Korean ginseng. Endophytic fungi were isolated from healthy leaves of mountain-cultivated ginseng (MCG) and field-cultivated ginseng (FCG) at 4 sites in Chungbuk Province. A total of 24 species of fungal endophytes were identified using molecular approaches. Additionally, the diversity of these endophytic fungi was compared between MCG and FCG. The major isolated endophytes were Edenia gomezpompae and Gibberella moniliformis in the MCG and FCG samples, respectively. The results suggest that ginseng endophytes have different community structures in different environments, and this understanding may prove useful in ginseng cultivation. PMID:25071383

Eo, Ju-Kyeong; Choi, Min-Seok

2014-01-01

328

Field Trip.  

ERIC Educational Resources Information Center

Reports the results of a field trip to measure the intensity of electromagnetic fields generated by electronic devices in the home, in cars, at work, outside, and in places people visit during the day. Found that a person gets more intense exposure while working at a computer than by living next to an electrical substation. (MDH)

Sanders, Bill

1993-01-01

329

Magnetic Fields  

NSDL National Science Digital Library

This page and its annex describes, in trivial terms, the physics of magnetic fields and the history of its discovery. Included is the work of Halley, Oersted, Ampere and Maxwell. It also describes a way of demonstrating it in the classroom, using a vu-graph projector. Later sections #5, #5a and #6 extend this to magnetic field lines and electromagnetism.

Stern, David

2005-01-04

330

Molecular epidemiology and clinical implications of metallo-?-lactamase-producing Pseudomonas aeruginosa isolated from urine.  

PubMed

We conducted a study on molecular epidemiology and clinical implications of metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa isolated from urine. Over a 10-year period from 2001 through 2010, a total of 92 MBL-producing P. aeruginosa urine isolates were collected from patients (one isolate per patient) who were admitted to 5 hospitals in Okayama Prefecture, Japan. When cross-infection was suspected in the hospital, pulsed-field gel electrophoresis was performed. In the resulting dendrogram of 79 MBL-producing P. aeruginosa urine isolates, no identical isolates and 7 pairs of isolates with >80% similarity were found. The biofilm-forming capabilities of 92 MBL-producing P. aeruginosa urine isolates were significantly greater than those of 92 non-MBL-producing urine isolates in a medium of modified artificial urine. The imipenem resistance transferred in 16 of 18 isolates tested, and these frequencies were in the range of 10?³ to 10??. All of 18 isolates tested belonged to internationally spread sequence type 235 and had 3 gene cassettes of antimicrobial resistance genes in the class 1 integron. The strong biofilm-forming capabilities of MBL-producing P. aeruginosa urine isolates could be seriously implicated in nosocomial infections. To prevent spread of the organism and transferable genes, effective strategies to inhibit biofilm formation in medical settings are needed. PMID:24743784

Sako, Shinichi; Kariyama, Reiko; Mitsuhata, Ritsuko; Yamamoto, Masumi; Wada, Koichiro; Ishii, Ayano; Uehara, Shinya; Kokeguchi, Susumu; Kusano, Nobuchika; Kumon, Hiromi

2014-01-01

331

Dielectrophoretic isolation and detection of cfc-DNA nanoparticulate biomarkers and virus from blood.  

PubMed

Dielectrophoretic (DEP) microarray devices allow important cellular nanoparticulate biomarkers and virus to be rapidly isolated, concentrated, and detected directly from clinical and biological samples. A variety of submicron nanoparticulate entities including cell free circulating (cfc) DNA, mitochondria, and virus can be isolated into DEP high-field areas on microelectrodes, while blood cells and other micron-size entities become isolated into DEP low-field areas between the microelectrodes. The nanoparticulate entities are held in the DEP high-field areas while cells are washed away along with proteins and other small molecules that are not affected by the DEP electric fields. DEP carried out on 20 ?L of whole blood obtained from chronic lymphocytic leukemia patients showed a considerable amount of SYBR Green stained DNA fluorescent material concentrated in the DEP high-field regions. Whole blood obtained from healthy individuals showed little or no fluorescent DNA materials in the DEP high-field regions. Fluorescent T7 bacteriophage virus could be isolated directly from blood samples, and fluorescently stained mitochondria could be isolated from biological buffer samples. Using newer DEP microarray devices, high-molecular-weight DNA could be isolated from serum and detected at levels as low as 8-16 ng/mL. PMID:23436471

Sonnenberg, Avery; Marciniak, Jennifer Y; McCanna, James; Krishnan, Rajaram; Rassenti, Laura; Kipps, Thomas J; Heller, Michael J

2013-04-01

332

Demonstration of an optical isolator by use of a nonreciprocal phase shift.  

PubMed

The experimental study of an optical isolator by use of a nonreciprocal phase shift is demonstrated. The isolator has an optical interferometer composed of tapered couplers, nonreciprocal phase shifters, and a reciprocal phase shifter. The isolator, designed for a 1.55-microm wavelength, was fabricated to investigate the characteristics of each component. The branching and coupling characteristics of the tapered coupler were measured. The nonreciprocal and reciprocal phase shifts were also evaluated. By applying an external magnetic field to the interferometer, we confirmed the nonreciprocal phase shift in the interferometric isolator. PMID:18324294

Yokoi, H; Mizumoto, T; Takano, T; Shinjo, N

1999-12-20

333

Root Galling and Reproduction of Meloidogyne incognita Isolates from Texas on Resistant Cotton Genotypes.  

PubMed

Several cotton genotypes with resistance to Meloidogyne incognita have been released in recent years. To estimate the durability of this resistance, galling severity on these resistant genotypes by M. incognita was measured. Nematode isolates (115 total) were collected from cotton fields in 14 Texas counties in August and September 1996 and 1997. Four additional isolates from Maryland, Mississippi, and North Carolina were also tested. The isolates were evaluated in 12 greenhouse experiments for their ability to gall roots of the resistant cotton genotypes M315, Acala NemX, and Stoneville LA887 and the susceptible cultivar Deltapine 90. Numbers of galls on each genotype by each isolate were counted 60 days after inoculation with 10,000 eggs/plant. M315 consistently had the fewest galls for each nematode isolate, whereas Deltapine 90 had the greatest number of galls. Numbers of galls on NemX and LA887 were usually intermediate and more variable. For each separate experiment, analysis of variance indicated that the effects of nematode isolates, cotton genotypes, and isolate-genotype interaction were significant (P < 0.05). In two of the experiments, nematode reproduction was also measured and galling was positively correlated (r = 0.68 and 0.86) with egg production by M. incognita. Nematode isolates from one field exhibited higher root galling and reproduction (P < 0.05) on resistant genotypes than other isolates, suggesting a need for gene deployment systems that will enhance the durability of resistance. PMID:19271003

Zhou, E; Wheeler, T A; Starr, J L

2000-12-01

334

Passive vibration isolation using a Roberts linkage  

Microsoft Academic Search

The article present an ultralow frequency passive vibration isolation device as part of the preisolation stage for the Australian International Gravitational Observatory (AIGO). This isolator is based on the Roberts linkage and simulates a very long radius conical pendulum to provide two-dimensional isolation. It is designed as the second horizontal isolation component of the preisolator and it will support the

F. Garoi; J. Winterflood; L. Ju; J. Jacob; D. G. Blair

2003-01-01

335

Bacteria isolated from amoebae/bacteria consortium  

DOEpatents

New protozoan derived microbial consortia and method for their isolation are provided. Consortia and bacteria isolated therefrom are useful for treating wastes such as trichloroethylene and trinitrotoluene. Consortia, bacteria isolated therefrom, and dispersants isolated therefrom are useful for dispersing hydrocarbons such as oil, creosote, wax, and grease.

Tyndall, R.L.

1995-05-30

336

Social Recovery by Isolation-Reared Monkeys  

Microsoft Academic Search

Total social isolation of macaque monkeys for at least the first 6 months of life consistently produces severe deficits in virtually every aspect of social behavior. Experiments designed to rehabilitate monkeys reared in isolation are described. While young isolates exposed to equal-age normal peers achieved only limited recovery of simple social responses, some mothers reared in isolation eventually exhibited acceptable

Harry F. Harlow; Stephen J. Suomi

1971-01-01

337

Entropy of isolated horizons revisited  

SciTech Connect

The decade-old formulation of the isolated horizon classically and within loop quantum gravity, and the extraction of the microcanonical entropy of such a horizon from this formulation, is reviewed, in view of recent renewed interest. There are two main approaches to this problem: one employs an SU(2) Chern-Simons theory describing the isolated horizon degrees of freedom, while the other uses a reduced U(1) Chern-Simons theory obtained from the SU(2) theory, with appropriate constraints imposed on the spectrum of boundary states ''living'' on the horizon. It is shown that both these ways lead to the same infinite series asymptotic in the horizon area for the microcanonical entropy of an isolated horizon. The leading area term is followed by an unambiguous correction term logarithmic in area with a coefficient -(3/2), with subleading corrections dropping off as inverse powers of the area.

Basu, Rudranil; Kaul, Romesh K.; Majumdar, Parthasarathi [SN Bose National Centre for Basic Sciences, Kolkata 700 098 (India); Institute of Mathematical Sciences, Chennai 600 113 (India); Saha Institute of Nuclear Physics, Kolkata 700 064 (India)

2010-07-15

338

Perceived Social Isolation and Cognition  

PubMed Central

Social species, from Drosophila melanogaster to Homo sapiens, fare poorly when isolated. Homo sapiens, an irrepressibly meaning-making species, are, in normal circumstances, dramatically affected by perceived social isolation. Research indicates that perceived social isolation (i.e., loneliness) is a risk factor for, and may contribute to, poorer overall cognitive performance, faster cognitive decline, poorer executive functioning, more negativity and depressive cognition, heightened sensitivity to social threats, a confirmatory bias in social cognition that is self-protective and paradoxically self-defeating, heightened anthropomorphism, and contagion that threatens social cohesion. These differences in attention and cognition impact emotions, decisions, behaviors, and interpersonal interactions that may contribute to the association between loneliness and cognitive decline and between loneliness and morbidity more generally. PMID:19726219

Cacioppo, John T.; Hawkley, Louise C.

2009-01-01

339

Reactor steam isolation cooling system  

SciTech Connect

This patent describes a reactor steam isolation cooling system. It comprises: a containment building having a containment wall; a reactor pressure vessel disposed inside the containment building and including a nuclear reactor core therein operable for generating reactor steam; an isolation pool disposed outside the containment building and adjacent to the containment wall and containing pool water; an isolation condenser including: a plurality of parallel heat pipes; a tube sheet disposed between the hot and cold tubes and through which the heat pipes are disposed in sealing contact therewith; and means for selectively channeling the reactor steam from the pressure vessel between the hot tubes of the evaporator assembly for removing heat therefrom to form reactor condensate.

Dillmann, C.W.

1992-10-27

340

Perceived social isolation and cognition.  

PubMed

Social species, from Drosophila melanogaster to Homo sapiens, fare poorly when isolated. Homo sapiens, an irrepressibly meaning-making species, are, in normal circumstances, dramatically affected by perceived social isolation. Research indicates that perceived social isolation (i.e. loneliness) is a risk factor for, and may contribute to, poorer overall cognitive performance, faster cognitive decline, poorer executive functioning, increased negativity and depressive cognition, heightened sensitivity to social threats, a confirmatory bias in social cognition that is self-protective and paradoxically self-defeating, heightened anthropomorphism and contagion that threatens social cohesion. These differences in attention and cognition impact on emotions, decisions, behaviors and interpersonal interactions that can contribute to the association between loneliness and cognitive decline and between loneliness and morbidity more generally. PMID:19726219

Cacioppo, John T; Hawkley, Louise C

2009-10-01

341

Floral odour and reproductive isolation in two species of Silene.  

PubMed

Mechanisms preventing interspecific pollination are important in closely related plant species, in particular when post-zygotic barriers are weak or absent. We investigated the role of floral odour in reproductive isolation between the two closely related species Silene latifolia and S. dioica. First, we tested whether floral odour composition and emission differed between the species. We found significant odour differences, but contrary to expectations, both species showed a rhythmic emission of the same compounds between day and night. Second, in a field experiment, odour of the two species was made more similar by applying phenylacetaldehyde to flowers. This manipulation led to higher pollen-analogue transfer between species, revealing that floral odour differences are important for maintaining reproductive isolation. We conclude that differences in single key compounds can reduce pollen transfer across species boundaries by pollinators and demonstrate that odour differences are an important component of premating floral isolation between closely related plant species. PMID:18031491

Waelti, M O; Muhlemann, J K; Widmer, A; Schiestl, F P

2008-01-01

342

Attosecond nonlinear optics using gigawatt-scale isolated attosecond pulses  

PubMed Central

High-energy isolated attosecond pulses required for the most intriguing nonlinear attosecond experiments as well as for attosecond-pump/attosecond-probe spectroscopy are still lacking at present. Here we propose and demonstrate a robust generation method of intense isolated attosecond pulses, which enable us to perform a nonlinear attosecond optics experiment. By combining a two-colour field synthesis and an energy-scaling method of high-order harmonic generation, the maximum pulse energy of the isolated attosecond pulse reaches as high as 1.3??J. The generated pulse with a duration of 500?as, as characterized by a nonlinear autocorrelation measurement, is the shortest and highest-energy pulse ever with the ability to induce nonlinear phenomena. The peak power of our tabletop light source reaches 2.6?GW, which even surpasses that of an extreme-ultraviolet free-electron laser. PMID:24158092

Takahashi, Eiji J.; Lan, Pengfei; Mucke, Oliver D.; Nabekawa, Yasuo; Midorikawa, Katsumi

2013-01-01

343

Interactions of cadmium, zinc, and phosphorus in marine Synechococcus : field uptake, physiological and proteomic studies  

E-print Network

A combination of uptake field studies on natural phytoplankton assemblages and laboratory proteomic and physiological experiments on cyanobacterial isolates were conducted investigating the interactions of cadmium (Cd), ...

Cox, Alysia Danielle

2011-01-01

344

[Neuronal activity of the "isolated hippocampus"].  

PubMed

Spontaneous and evoked activity of the field CA1 neurones were investigated in long-lasting experiments on unanesthetized rabbits with "isolated hippocampus" (destruction of both septal and perforant path's afferents). Testing by various sensory stimuli as well as by electrical stimulation of Schaffer's collateral's, subiculum, posterior cingulate cortex, neocortex and midbrain reticular formation was used. The sensory reactions were virtually absent during first 1--2 weeks after the operation, but by the 4--6th week the level of reactivity became normal (65--70%). The first sensory reactions encountered were of diffuse tonic type; later on complex patterned on-responses appeared. The sources of hippocampal reactions, the possibility of plastic rearrangement of synapses and the absence of intrinsinc ability for generation of the theta-activity are discussed. PMID:654577

Brazhnik, E S; Vinogradova, O S

1978-01-01

345

Soot agglomeration in isolated, free droplet combustion  

NASA Technical Reports Server (NTRS)

Under the conditions of an isolated, free droplet experiment, hollow, carbonaceous structures, called soot spheres, were observed to form during the atmospheric pressure, low Reynolds number combustion of 1-methylnaphthalene. These structures which are agglomerates composed of smaller spheroidal units result from both thermophoretic effects induced by the envelope flame surrounding each drop and aerodynamic effects caused by changes in the relative gas/drop velocities. A chemically reacting flow model was used to analyze the process of sootshell formation during microgravity droplet combustion. The time-dependent temperature and gas property field surrounding the droplet was determined, and the soot cloud location for microgravity combustion of n-heptane droplets was predicted. Experiments showed that the sooting propensity of n-alkane fuel droplets can be varied through diluent substitution, oxygen-index variations, and ambient pressure reductions.

Choi, M. Y.; Dryer, F. L.; Green, G. J.; Sangiovanni, J. J.

1993-01-01

346

Microwave effects on isolated chick embryo hearts  

SciTech Connect

This study was designed to examine the effects of microwaves on the electric activity of hearts as a means of elucidating interactive mechanisms of nonionizing radiation with cardiac tissue. Experiments were performed on isolated hearts of 9-12-day-old chick embryos placed in small petri dishes. Oxygenated isotonic Ringer's solution at 37 degrees C permitted heart survival. Samples were irradiated at 2.45 GHz with a power density of 3 mW/cm2. The heart signal was detected with a glass micropipet inserted into the sinoatrial node and examined by means of a Berg-Fourier analyzer. Pulsed microwaves caused the locking of the heartbeat to the modulation frequency, whereas continuous wave irradiation might have induced slight bradycardia. Pulsed fields induced stimulation or regularization of the heartbeat in arrhythmia, fibrillation, or arrest of the heart.

Caddemi, A.; Tamburello, C.C.; Zanforlin, L.; Torregrossa, M.V.

1986-01-01

347

Field Guides  

NSDL National Science Digital Library

This reference includes individual titles of note along with the most popular field guide series. For each guide, the author, publisher, and publication date are given. The diverse list has 17 individual titles, which cover everything from wildflowers in the Colorado mountains and insects north of Mexico to the natural history of vacant lots. There are detailed descriptions of four of the most popular field guide series: Audubon Society Guides, Golden Guides, Peterson Guides, and Stokes Nature Guide Series.

348

Double-gated isolated vertically aligned carbon nanofiber field emission and field ionization arrays  

E-print Network

Electron impact ionization (ElI) is used extensively in mass spectrometry for gas-phase analytes. Due to the significant amount of fragmentation generated by ElI, the spectrum is usually very noisy. In addition, the ...

Chen, Liang-Yu, 1979-

2007-01-01

349

Genetic diversity among Borrelia burgdorferi isolates from wood rats and kangaroo rats in California.  

PubMed Central

Twenty-nine Borrelia burgdorferi isolates, obtained from dusky-footed wood rats (Neotoma fuscipes) and California kangaroo rats (Dipodomys californicus) in California, were analyzed genetically. Chromosomal DNA was examined by restriction endonuclease analysis (REA) and gene probe restriction fragment length polymorphism. Pulsed-field gel electrophoresis was used to analyze the plasmid profiles of the isolates. REA, the method with the greatest discrimination, disclosed 24 distinct restriction patterns among the 29 isolates. These restriction patterns were sorted into four restriction fragment length polymorphism groups on the basis of their gene hybridization patterns. Results of the REA and plasmid profile analysis supported this grouping. The degree of genetic diversity among Californian isolates demonstrated by our findings is greater than that previously reported among other groups of North American isolates and is similar or greater than the diversity reported among European isolates. Images PMID:7905880

Zingg, B C; Brown, R N; Lane, R S; LeFebvre, R B

1993-01-01

350

Selected fault testing of electronic isolation devices used in nuclear power plant operation  

SciTech Connect

Electronic isolation devices are used in nuclear power plants to provide electrical separation between safety and non-safety circuits and systems. Major fault testing in an earlier program indicated that some energy may pass through an isolation device when a fault at the maximum credible potential is applied in the transverse mode to its output terminals. During subsequent field qualification testing of isolators, concerns were raised that the worst case fault, that is, the maximum credible fault (MCF), may not occur with a fault at the maximum credible potential, but rather at some lower potential. The present test program investigates whether problems can arise when fault levels up to the MCF potential are applied to the output terminals of an isolator. The fault energy passed through an isolated device during a fault was measured to determine whether the levels are great enough to potentially damage or degrade performance of equipment on the input (Class 1E) side of the isolator.

Villaran, M.; Hillman, K.; Taylor, J.; Lara, J.; Wilhelm, W. [Brookhaven National Lab., Upton, NY (United States)

1994-05-01

351

Molecular characterization of methicillin-resistant Staphylococcus aureus isolated from a Brazilian university hospital.  

PubMed

The aim of this study was to perform SCCmec typing in Staphylococcus aureus isolates and to characterize the clonal profile of these isolates. Forty-six mecA gene-positive strains isolated between 2002 and 2006 were submitted to antimicrobial resistance testing by the E-test, SCCmec typing by multiplex PCR, and clonal profile analysis by pulsed-field gel electrophoresis. Forty-one (89.1%) isolates were typed as SCCmec III and five (10.9%) as SCCmec IV. Four circulating clones were detected, one of them comprising isolates related to the Brazilian epidemic clone. This clone was detected throughout the study period. The SCCmec III isolates were associated with a high rate of multidrug resistance and clonal dissemination of methicillin-resistant S. aureus in the wards of the University Hospital of the Botucatu School of Medicine, Universidade Estadual Paulista. PMID:24389283

Martins, André; Riboli, Danilo Flávio Moraes; Pereira, Valéria Cataneli; Cunha, Maria de Lourdes Ribeiro de Souza da

2014-01-01

352

Random Fields  

NASA Astrophysics Data System (ADS)

Random variation over space and time is one of the few attributes that might safely be predicted as characterizing almost any given complex system. Random fields or "distributed disorder systems" confront astronomers, physicists, geologists, meteorologists, biologists, and other natural scientists. They appear in the artifacts developed by electrical, mechanical, civil, and other engineers. They even underlie the processes of social and economic change. The purpose of this book is to bring together existing and new methodologies of random field theory and indicate how they can be applied to these diverse areas where a "deterministic treatment is inefficient and conventional statistics insufficient." Many new results and methods are included. After outlining the extent and characteristics of the random field approach, the book reviews the classical theory of multidimensional random processes and introduces basic probability concepts and methods in the random field context. It next gives a concise amount of the second-order analysis of homogeneous random fields, in both the space-time domain and the wave number-frequency domain. This is followed by a chapter on spectral moments and related measures of disorder and on level excursions and extremes of Gaussian and related random fields. After developing a new framework of analysis based on local averages of one-, two-, and n-dimensional processes, the book concludes with a chapter discussing ramifications in the important areas of estimation, prediction, and control. The mathematical prerequisite has been held to basic college-level calculus.

Vanmarcke, Erik

1983-03-01

353

[Isolated giant hydatid in kidney].  

PubMed

Cyst hydatid of the kidney is parasitic condition caused by Echinococcus granulosus and identified in many countries, especially associated with sheep farming. Echinococcal larvae enter the bloodstream using the digestive system and invade any organs in the human body. The urinary system is the third most common area affected by parasitic infection after liver and lungs, but isolated renal involvement is a very rare situation, even in endemic areas. ?n our case, we aimed to report a 57-year-old female patient with an 18-centimeter isolated renal cyst hydatid treated by retroperitoneal nephrectomy. The diagnosis was based on imaging findings and confirmed by histopathologically. PMID:25016121

Ozgör, Faruk; Erbin, Akif; Berbero?lu, Ahmet Yalç?n; Binbay, Murat; Sar?lar, Omer; Müslümano?lu, Ahmet Yaser

2014-06-01

354

Isolation of DNA and RNA.  

PubMed

Blood samples for most coagulation tests are collected into 3.8% trisodium citrate in a ratio of 1 part anticoagulant to 9 parts blood. Whole-blood samples for DNA isolation can be stored at -50°C and the DNA prepared at a later stage. A more convenient method requiring less freezer space is to store buffy coats-the interface between the red cells and the plasma that is seen following centrifugation of whole blood. This latter method also allows isolation of the plasma fraction. PMID:21340978

Perry, D J

1999-01-01

355

Holden Crater Dune Field  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

A common location for dune fields on Mars is in the basin of large craters. This dune field is located in Holden Crater at 25 degrees South atitude.

Image information: VIS instrument. Latitude -25.5, Longitude 326.8 East (33.2 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2005-01-01

356

Biodiversity of Clostridium botulinum Type E Strains Isolated from Fish and Fishery Products  

PubMed Central

The genetic biodiversity of Clostridium botulinum type E strains was studied by pulsed-field gel electrophoresis (PFGE) with two macrorestriction enzymes (SmaI-XmaI and XhoI) and by randomly amplified polymorphic DNA (RAPD) analysis with two primers (OPJ 6 and OPJ 13) to characterize 67 Finnish isolates from fresh fish and fishery products, 15 German isolates from farmed fish, and 10 isolates of North American or North Atlantic origin derived mainly from different types of seafood. The effects of fish species, processing, and geographical origin on the epidemiology of the isolates were evaluated. Cluster analysis based on macrorestriction profiles was performed to study the genetic relationships of the isolates. PFGE and RAPD analyses were combined and resulted in the identification of 62 different subtypes among the 92 type E isolates analyzed. High genetic biodiversity among the isolates was observed regardless of their source. Finnish and North American or North Atlantic isolates did not form distinctly discernible clusters, in contrast with the genetically homogeneous group of German isolates. On the other hand, indistinguishable or closely related genetic profiles among epidemiologically unrelated samples were detected. It was concluded that the high genetic variation was probably a result of a lack of strong selection factors that would influence the evolution of type E. The wide genetic biodiversity observed among type E isolates indicates the value of DNA-based typing methods as a tool in contamination studies in the food industry and in investigations of botulism outbreaks. PMID:10224001

Hyytia, Eija; Hielm, Sebastian; Bjorkroth, Johanna; Korkeala, Hannu

1999-01-01

357

Molecular Characterization of Pigmented and Nonpigmented Isolates of Mycobacterium avium subsp. paratuberculosis  

PubMed Central

Five pigmented isolates of Mycobacterium avium subsp. paratuberculosis were examined by pulsed-field gel electrophoresis (PFGE), IS900 restriction fragment length polymorphism (IS900-RFLP), and IS1311 polymorphism analysis using PCR. All of the pigmented isolates exhibited one of three distinct PFGE profiles with SnaBI, designated 9, 10, and 11, and with SpeI, designated 7, 8, and 9, which generated three multiplex profiles designated [9-7], [10-8], and [11-9]. All of the pigmented isolates had the same IS900-RFLP BstEII and PvuII profiles. The IS900-RFLP BstEII profile was new, but the IS900-RFLP PvuII profile corresponded to PvuII type 6 of a sheep strain described by Cousins and colleagues (D. V. Cousins, S. N. Williams, A. Hope, and G. J. Eamens, Aust. Vet. J. 78:184-190, 2000). IS1311-PCR analysis typed all of the pigmented isolates as sheep (S) strains. The genetic relationship between pigmented and nonpigmented isolates was investigated by using multiplex PFGE data from the analysis of both the 5 pigmented isolates and 88 nonpigmented isolates of M. avium subsp. paratuberculosis from a variety of host species and geographic locations. It was possible to classify the isolates into two distinct types designated type I, comprising the pigmented isolates, and type II, comprising the nonpigmented isolates, which exhibit a very broad host range. PMID:11980962

Stevenson, Karen; Hughes, Valerie M.; de Juan, Lucia; Inglis, Neil F.; Wright, Frank; Sharp, J. Michael

2002-01-01

358

High Frequency of Acinetobacter soli among Acinetobacter Isolates Causing Bacteremia at a Tertiary Hospital in Japan  

PubMed Central

Acinetobacter baumannii is generally the most frequently isolated Acinetobacter species. Sequence analysis techniques allow reliable identification of Acinetobacter isolates at the species level. Forty-eight clinical isolates of Acinetobacter spp. were obtained from blood cultures at Tohoku University Hospital. These isolates were identified at the species level by partial sequencing of the RNA polymerase ?-subunit (rpoB), 16S rRNA, and gyrB genes. Then further characterization was done by using the PCR for detection of OXA-type ?-lactamase gene clusters, metallo-?-lactamases, and carO genes. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing were also performed. The most frequent isolate was Acinetobacter soli (27.1%). Six of the 13 A. soli isolates were carbapenem nonsusceptible, and all of these isolates produced IMP-1. PFGE revealed that the 13 A. soli isolates were divided into 8 clusters. This study demonstrated that A. soli accounted for a high proportion of Acinetobacter isolates causing bacteremia at a Japanese tertiary hospital. Non-A. baumannii species were identified more frequently than A. baumannii and carbapenem-nonsusceptible isolates were found among the non-A. baumannii strains. These results emphasize the importance of performing epidemiological investigations of Acinetobacter species. PMID:24403303

Yano, Hisakazu; Kanamori, Hajime; Inomata, Shinya; Aoyagi, Tetsuji; Hatta, Masumitsu; Gu, Yoshiaki; Tokuda, Koichi; Kitagawa, Miho; Kaku, Mitsuo

2014-01-01

359

Isolation and Characterization of Glycopeptide-Resistant Enterococci from Hospitalized Patients over a 30-Month Period  

PubMed Central

In February 1996, a Hospital Infection Control Practices Advisory Committee-style screening program was commenced to isolate and subsequently characterize glycopeptide-resistant enterococci (GRE) from patients at a hospital trust in Glasgow, Scotland. Over the next 30 months, GRE were isolated from 154 patients. GRE were isolated from patients in traditionally high-risk areas such as the renal unit and intensive care unit and also in areas considered to be lower risk, including medical wards and associated long-stay geriatric hospitals. The majority (90%) of isolates were Enterococcus faecium vanB. The remaining isolates consisted of seven E. faecalis (vanA), three E. gallinarum (vanC), and a further six E. faecium (five vanA, one both vanA and vanB) isolates. Analysis of SmaI-digested DNA by pulsed-field gel electrophoresis revealed that 34 of 40 (85%) VanB E. faecium isolates were identical or closely related, while 11 of 13 (85%) VanA GRE were distinct. High-level aminoglycoside resistance was seen in less than 8% of isolates. VanB E. faecium isolates were almost uniformly resistant to ampicillin and tetracycline. In this study, GRE have been isolated over a prolonged period from a broad range of patients. Glycopeptide resistance within the study hospital trust appeared to be mainly due to the clonal dissemination of a single strain of E. faecium VanB. PMID:10834962

Nelson, R. R. S.; McGregor, K. F.; Brown, A. R.; Amyes, S. G. B.; Young, H.-K.

2000-01-01

360

Clinical and molecular epidemiology of hospital Enterococcus faecalis isolates in eastern France.  

PubMed

OBJECTIVE: To report on the occurrence of Enterococcus faecalis hospital isolates obtained during 1 year in hospitals in the Franche-Comté region of France. METHODS: Clinical isolates of E. faecalis of different antibiotic susceptibility phenotypes from hospitalized patients were characterized by pulsed-field gel electrophoresis. Patients with positive cultures were investigated by three case-control studies to identify risk factors for colonization/infection. RESULTS: The crude incidence of colonization/infection was 2.37%, and 4-day and 7-day colonization rates after admission were 10.0% and 6.36%, respectively. The rates of high-level resistance to kanamycin (HLKR) and to gentamicin (HLGR) were 47.1% and 7.1%, respectively. No isolate was resistant to glycopeptides or produced beta-lactamase. The 209 hospital isolates obtained during the study yielded 98 major DNA patterns, of which two were major epidemic patterns including HLKR isolates. No single factor was significantly associated with colonization/infection by HLKR isolates. The length of hospitalization before isolation was associated with colonization by HLGR isolates. CONCLUSIONS: The isolation frequency of E. faecalis strains with acquired resistance to aminoglycoside antibiotics, and the wide dissemination of resistant strains with characteristics that allow them to persist and spread, argue for further large prospective surveys of clinical isolates of E. faecalis in hospitals. PMID:11856239

Mulin, Blandine; Bailly, Pascale; Thouverez, Michelle; Cailleaux, Vincent; Cornette, Christian; Dupont, Marie-Jeanne; Talon, Daniel

1999-03-01

361

Community-associated Methicillin-resistant Staphylococcus aureus Isolates and Healthcare-Associated Infections1  

PubMed Central

We noted a marked increase in healthcare-associated (HA) methicillin-resistant Staphylococcus aureus (MRSA) infections caused by isolates phenotypically consistent with community-associated (CA)-MRSA strains. To study this trend, we retrospectively examined all HA-MRSA isolates from patients in our institution during 1999–2004. An isolate was considered an SCCmecIV phenotype if it had antimicrobial drug susceptibilities consistent with typical CA-MRSA isolates. Our phenotypic definition was validated in a limited subset of isolates by SCCmec genotype, pulsed-field gel electrophoresis, and multilocus sequence typing. Among 352 patients with HA-MRSA isolates, SCCmecIV phenotype increased from 17% in 1999 to 56% in 2003 (p<0.0001). Antimicrobial drug-susceptibility phenotype and genotype were consistent in 21 (91%) of 23 isolates. In a multivariate model, the SCCmec type IV phenotype was independently associated with wound culture source, later year of collection, and MRSA isolated earlier during hospitalization. In conclusion, MRSA isolates phenotypically similar to CA strains have become the predominant isolates associated with HA-MRSA in our hospital. PMID:17479885

Maree, Cynthia L.; Daum, Robert S.; Boyle-Vavra, Susan; Matayoshi, Kelli

2007-01-01

362

Primary isolation of shiga toxigenic from environmental sources.  

PubMed

Since the time of the first microbe hunters, primary culture and isolation of bacteria has been a foundation of microbiology. Like other microbial methods, bacterial culture and isolation methodologies continue to develop. Although fundamental concepts like selection and enrichment are as relevant today as they were over 100 yr ago, advances in chemistry, molecular biology and bacterial ecology mean that today's culture and isolation techniques serve additional supporting roles. The primary isolation of Shiga toxigenic (STEC) from environmental sources relies on enriching the target while excluding extensive background flora. Due to the complexity of environmental substrates, no single method can be recommended; however, common themes are discussed. Brilliant Green Bile Broth, with or without antibiotics, is one of many broths used successfully for selective STEC enrichment. Stressed cells may require a pre-enrichment recovery step in a nonselective broth such as buffered peptone water. After enrichment, immunomagnetic separation with serotype specific beads drastically increases the chances for recovery of STEC from environmental or insect sources. Some evidence suggests that acid treating the recovered beads can further enhance isolation. Although it is common in human clinical, food safety, and water quality applications to plate the recovered beads on Sorbitol MacConkey Agar, other chromogenic media, such as modified CHROMagar, have proven helpful in field and outbreak applications, allowing the target to be distinguished from the numerous background flora. Optimum conditions for each sample and target must be determined empirically, highlighting the need for a better understanding of STEC ecology. PMID:24216409

Durso, Lisa M

2013-09-01

363

High performance millimeter-wave microstrip circulators and isolators  

NASA Technical Reports Server (NTRS)

Millimeter wave systems, phased array antennas, and high performance components all require wideband circulators (and isolators) to perform diplexing and switching, to improve isolation and Voltage Standing Wave Ratio (VSWR), and to construct IMPATT diode reflection amplifiers. Presently, most of the millimeter-wave circulators and isolators are available in the configurations of waveguide or stripline, both of which suffer from the shortcomings of bulky size/weight, narrow bandwidth, and poor compatibility with monolithic millimeter-wave integrated circuits (MMIC). MMW microstrip circulators/isolators can eliminate or improve these shortcomings. Stub-tuned microstrip circulator configuration were developed utilizing the electromagnetic fields perturbation technique, the adhesion problems of microstrip metallization on new ferrite substrate were overcome, the fabrication, assembly, packaging techniques were improved, and then successfully designed, fabricated a Ka band circulator which has isolation and return loss of greater than 16dB, insertion loss less than 0.7dB. To assess the steady and reliable performance of the circulator, a temperature cycling test was done over the range of -20 to +50 C for 3 continuous cycles and found no significant impact or variation of circulator performance.

Shih, Ming; Pan, J. J.

1990-01-01

364

Are Small, Isolated Wetlands Expendable?  

Microsoft Academic Search

What is most evident in the recent debate concerning new wetland regulations drafted by the U.S. Army Corps of Engineers is that small, isolated wetlands will likely continue to be lost. The critical biological question is whether small wetlands are expendable, and the fundamental issue is the lack of biologically rele- vant data on the value of wetlands, especially so-called

Raymond D. Semlitsch; J. Russell Bodie

1998-01-01

365

Breaking the Barriers of Isolation.  

ERIC Educational Resources Information Center

Discusses the College of Eastern Utah's San Juan Center for Higher Education which was designed to serve San Juan County's isolated and economically disadvantaged population. Describes the diverse educational needs of county residents, the center's administration, cooperative arrangements, the use of community facilities and itinerant instructors,…

Potter, Van

1980-01-01

366

Isolated Singularities and Series Expansions  

NSDL National Science Digital Library

Created by Lang Moore and David Smith for the Connected Curriculum Project, the purposes of this module are to experiment with Taylor and Laurent series commands in a computer algebra system and to explore the behavior of differentiable functions near isolated singularities. This is one within a much larger set of learning modules hosted by Duke University.

Moore, Lang; Smith, David

2010-06-30

367

Mitochondria: isolation, structure and function  

PubMed Central

Abstract Mitochondria are complex organelles constantly undergoing processes of fusion and fission, processes that not only modulate their morphology, but also their function. Yet the assessment of mitochondrial function in skeletal muscle often involves mechanical isolation of the mitochondria, a process which disrupts their normally heterogeneous branching structure and yields relatively homogeneous spherical organelles. Alternatively, methods have been used where the sarcolemma is permeabilized and mitochondrial morphology is preserved, but both methods face the downside that they remove potential influences of the intracellular milieu on mitochondrial function. Importantly, recent evidence shows that the fragmented mitochondrial morphology resulting from routine mitochondrial isolation procedures used with skeletal muscle alters key indices of function in a manner qualitatively similar to mitochondria undergoing fission in vivo. Although these results warrant caution when interpreting data obtained with mitochondria isolated from skeletal muscle, they also suggest that isolated mitochondrial preparations might present a useful way of interrogating the stress resistance of mitochondria. More importantly, these new findings underscore the empirical value of studying mitochondrial function in minimally disruptive experimental preparations. In this review, we briefly discuss several considerations and hypotheses emerging from this work. PMID:21708903

Picard, Martin; Taivassalo, Tanja; Gouspillou, Gilles; Hepple, Russell T

2011-01-01

368

Anaphylaxis in Isolated Rabbit Lungs  

Microsoft Academic Search

Lungs from rabbits sensitized to ovalbumin or bovine ?-globulin were isolated and perfused with autologous blood. The response to antigen challenge via the perfusate was immunologically specific and characterized by a marked increase in perfusion resistance, a moderate increase in airway resistance and a small decrease in lung compliance. The response could also be elicited by specific antigen challenge in

T. S. Hakim; C. A. Dawson; V. L. Moore; J. J. Barboriak

1978-01-01

369

Resisting an Isolated Learning Discourse  

ERIC Educational Resources Information Center

The primary objective of this paper is to suggest that researchers on workplace learning avoid an isolated learning discourse. The point at issue is that being a learner is just one aspect of people's sometimes complicated lives in the workplace, and that people may sometimes--for good reasons--resist a learning discourse if it is linked…

Tanggaard, Lene

2009-01-01

370

Isolation and identification among cockle isolates of Vibrio vulnificus isolated from Selangor, Malaysia  

NASA Astrophysics Data System (ADS)

Vibrio vulnificus infections are worldwide public health problems associated with illnesses resulting from consumption of raw or partially cooked seafood. The aim of this study was to investigate the presence and identification of V. vulnificus in cockles from local wet (40) and supermarkets (38) from Selangor, Malaysia from July 2013 to February 2014. A total of 78(n=78) cockle were examined for the presence of V. vulnificus and at about 32% (25/78) cockle samples were positive to this bacterium. Colonies morphological observation and biochemical characterization for those isolates showed 60% (15/78) of isolates were classified as biotype 1 and 40% (10/78) belong to biotype 2.

Kurdi Al-Dulaimi, Mohammed M.; Mutalib, Sahilah Abd.; Ghani, Ma`aruf Abd.

2014-09-01

371

Genotypic Characterization of Streptococcus infantarius subsp. coli Isolates from Sea Otters with Infective Endocarditis and/or Septicemia and from Environmental Mussel Samples  

PubMed Central

Pulsed-field gel electrophoresis (PFGE) was used to type 128 Streptococcus infantarius subsp. coli isolates from sea otters and mussels. Six SmaI PFGE groups were detected, with one predominant group representing 57% of the isolates collected over a wide geographic region. Several sea otter and mussel isolates were highly related, suggesting that an environmental infection source is possible. PMID:23052307

Counihan-Edgar, Katrina L.; Gill, Verena A.; Doroff, Angela M.; Burek, Kathleen A.; Miller, Woutrina A.; Shewmaker, Patricia L.; Jang, Spencer; Goertz, Caroline E. C.; Tuomi, Pamela A.; Miller, Melissa A.; Jessup, David A.

2012-01-01

372

Cardiogenic Field  

NSDL National Science Digital Library

This simple FlashTM animation depicts development of the cardiogenic field in the trilaminar germ disc. It begins with a ventral view of a bilaminar disc with a transparent endoderm. Clicking causes the embryo to advance through the trilaminar stage showing mesenchymal cells invaginating though the primitive streak and spreading throughout the germ disc. Cardiogenic mesoderm cells are color coded red, other mesoderm cells are green. This allows users to see how the first cells to invaginate through the streak are specified to form the cardiogenic field and heart.

PhD Jack D Thatcher (West Virginia School of Osteopathic Medicine Structural Biology)

2009-11-20

373

Vector Fields  

NSDL National Science Digital Library

Vector fields are vectors which change from point to point. A standard example is the velocity of moving air, in other words, wind. For instance, the current wind pattern in the San Francisco area can be found at . This site has a 2-dimensional representation; careful reading of the webpage will tell you at what elevation the wind is shown. How would you represent a vector field in 3 dimensions? What features are important? Some simple examples are shown. Each can be rotated by clicking and dragging with the mouse. Explore!

Ay, Tevian

2006-01-01

374

Degradation of atrazine by an acclimatized soil fungal isolate  

Microsoft Academic Search

A fungal strain able to use atrazine (2-chloro-4-ethylamino-5-isopropylamino-1,3,5-triazine) as a source of nitrogen was isolated from a corn field soil that has been previously treated with the herbicide. This strain was purified and acclimatized to atrazine at a higher level in the laboratory. A supplemented N was required to trigger the reaction. Atrazine was degraded at a faster rate in

Shashi B. Singh; Shashi P. Lal; Shashi Pant; Gita Kulshrestha

2008-01-01

375

Isolation and structure revision of pepluane diterpenoids from euphorbia peplus  

PubMed

A new pepluane diterpene polyester (2) was isolated from a CH2Cl2 extract of the whole, undried plant of Euphorbia peplus, together with the known compound 1. The structures were established by high-field spectroscopic methods, including 2D NMR techniques, and by X-ray crystallography, and the stereostructure of the first member of the pepluane diterpenoids (1) was revised. PMID:9917293

Hohmann; G nther G; Vasas; Kalman; Argay

1999-01-01

376

Isolation and Molecular Characterization of Leptospira interrogans and Leptospira borgpetersenii Isolates from the Urban Rat Populations of Kuala Lumpur, Malaysia  

PubMed Central

Rats are considered the principal maintenance hosts of Leptospira. The objectives of this study were isolation and identification of Leptospira serovars circulating among urban rat populations in Kuala Lumpur. Three hundred urban rats (73% Rattus rattus and 27% R. norvegicus) from three different sites were trapped. Twenty cultures were positive for Leptospira using dark-field microscopy. R. rattus was the dominant carrier (70%). Polymerase chain reaction (PCR) confirmed that all isolates were pathogenic Leptospira species. Two Leptospira serogroups, Javanica and Bataviae, were identified using microscopic agglutination test (MAT). Pulsed-field gel electrophoresis (PFGE) identified two serovars in the urban rat populations: L. borgpetersenii serovar Javanica (85%) and L. interrogans serovar Bataviae (15%). We conclude that these two serovars are the major serovars circulating among the urban rat populations in Kuala Lumpur. Despite the low infection rate reported, the high pathogenicity of these serovars raises concern of public health risks caused by rodent transmission of leptospirosis. PMID:23358635

Benacer, Douadi; Zain, Siti Nursheena Mohd; Amran, Fairuz; Galloway, Renee L.; Thong, Kwai Lin

2013-01-01

377

Arun field  

SciTech Connect

The Arun field is a giant gas-condensate field operated by Mobil and Pertamina with over 20,000 acres of closure at the top of the Arun reservoir. A middle-shelf patch reef complex of early to middle Miocene age is the producing facies at the Arun field. About 1,100 ft of porous limestones, encased in shales, create a stratigraphic trap for overpressure hydrocarbons. Three main carbonate lithologies were encountered during the examination of over 4,300 ft of core; (1) a reef facies consisting of vuggy, coral encrusting, red-algal boundstones, (2) a near-reef facies consisting of foraminiferal, mixed-skeletal packstones with gravel-size coral fragments, and (3) an interreef lagoonal facies consisting of benthonic-foram packstones. Twenty-two species of corals have been identified from Arun reef facies; major reef-forming coals, listed in order of decreasing abundance, are Porites cf P. Lutes, Cyphastrea microphthalma, Astreopora myriophthalma, Styloconiella gunetheri, Porites solida, and Acropora ssp. The Arun reef is comprised of limestones (with minor amounts of dolomite). No shale beds occur in the sequence, and all carbonate facies are in communication. A pervasive microporosity, occurring throughout the Arun Limestone, results from meteoric alteration of original carbonate mud to form a microrhombic porosity that accounts for about three-fourths of the field's total porosity.

Jordan, C.F. Jr.; Abdullah, M.

1988-01-01

378

Field Biology  

NSDL National Science Digital Library

This field biology class uses a service-learning project instead of a course term paper. The students worked with 4th and 5th graders at a local school to teach them skills in wildflower and fern identification, and then to help them implement a nature trail, which will be accessible to the greater community.

Course taught by Nancy Prentiss, University of Maine-Farmington, prentiss@maine.edu. Example compiled by Suzanne Savanick, Science Education Resource Center, ssavanic@carleton.edu.

379

Geochemical assessment of nuclear waste isolation. Report of activities during fiscal year 1982  

SciTech Connect

The status of the following investigations is reported: canister/overpack-backfill chemical interactions and mechanisms; backfill and near-field host rock chemical interactions mechanisms; far-field host rock geochemical interactions; verification and improvement of predictive algorithms for radionuclide migration; and geologic systems as analogues for long-term radioactive waste isolation.

Not Available

1983-07-01

380

Endophytic Bradyrhizobium spp. isolates from sugarcane obtained through different culture strategies.  

PubMed

Brazilian sugarcane has been shown to obtain part of its nitrogen via biological nitrogen fixation (BNF). Recent reports, based on the culture independent sequencing of bacterial nifH complementary DNA (cDNA) from sugarcane tissues, have suggested that members of the Bradyrhizobium genus could play a role in sugarcane-associated BNF. Here we report on the isolation of Bradyrhizobium spp. isolates and a few other species from roots of sugarcane cultivar RB867515 by two cultivation strategies: direct isolation on culture media and capture of Bradyrhizobium spp. using the promiscuous legume Vigna unguiculata as trap-plant. Both strategies permitted the isolation of genetically diverse Bradyrhizobium spp. isolates, as concluded from enterobacterial repetitive intergenic consensus polymerase chain reaction (PCR) fingerprinting and 16S ribosomal RNA, nifH and nodC sequence analyses. Several isolates presented nifH phylotypes highly similar to nifH cDNA phylotypes detected in field-grown sugarcane by a culture-independent approach. Four isolates obtained by direct plate cultivation were unable to nodulate V.?unguiculata and, based on PCR analysis, lacked a nodC gene homologue. Acetylene reduction assay showed in vitro nitrogenase activity for some Bradyrhizobium spp. isolates, suggesting that these bacteria do not require a nodule environment for BNF. Therefore, this study brings further evidence that Bradyrhizobium spp. may play a role in sugarcane-associated BNF under field conditions. PMID:24992534

Rouws, Luc Felicianus Marie; Leite, Jakson; de Matos, Gustavo Feitosa; Zilli, Jerri Edson; Coelho, Marcia Reed Rodrigues; Xavier, Gustavo Ribeiro; Fischer, Doreen; Hartmann, Anton; Reis, Verônica Massena; Baldani, José Ivo

2014-08-01

381

Etiological differences between the isolated lateral ventricle and the isolated fourth ventricle  

Microsoft Academic Search

Objective  To determine if an etiological difference exists between isolation of the lateral ventricle and isolation of the fourth ventricle after ventricular shunting.Methods  Cases of symptomatic isolation of the lateral and fourth ventricles were reviewed retrospectively. The ages at presentation of ventricular isolation, the time course to development of isolation, the number of shunt surgeries leading up to symptomatic isolation, the types

Beng Ti Ang; Paul Steinbok; D. Douglas Cochrane

2006-01-01

382

Gauge Field Optics with Anisotropic Media  

E-print Network

By considering gauge transformations on the macroscopic Maxwell's equations, a two dimensional gauge field, with its pseudo magnetic field in the real space, is identified as tilted anisotropy in the constitutive parameters. We show that optical spin Hall effect and one-way edge states become possible simply by using anisotropic media with broadband response. The proposed gauge field also allows us to design an optical isolator based on the Aharonov-Bohm effect. Our approach will be useful in spoof magneto-optics with arbitrary magnetic fields mimicked by metamaterials with subwavelength unit cells. It also serves as a generic way to design polarization-dependent devices.

Liu, Fu

2014-01-01

383

Warm inflation in presence of magnetic fields  

E-print Network

We present preliminary results on the possible effects that primordial magnetic fields can have for a warm inflation scenario, based on global supersymmetry, with a new-inflation-type potential. This work is motivated by two considerations: first, magnetic fields seem to be present in the universe on all scales, which rises the possibility that they could also permeate the early universe; second, the recent emergence of inflationary models where the inflaton is not assumed to be isolated but instead it is taken as an interacting field, even during the inflationary expansion. The effects of magnetic fields are included resorting to Schwinger proper time method.

Gabriella Piccinelli; Angel Sanchez; Alejandro Ayala; Ana Julia Mizher

2013-11-03

384

Nili Patera Dune Field  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

This VIS image shows a dune field within Nili Patera, the northern caldera of a large volcanic complex in Syrtis Major.

Image information: VIS instrument. Latitude 9, Longitude 67 East (293 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2005-01-01

385

Crater Floor Dune Field  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site]

Our topic for the weeks of April 4 and April 11 is dunes on Mars. We will look at the north polar sand sea and at isolated dune fields at lower latitudes. Sand seas on Earth are often called 'ergs,' an Arabic name for dune field. A sand sea differs from a dune field in two ways: 1) a sand sea has a large regional extent, and 2) the individual dunes are large in size and complex in form.

Our final dune image shows a small dune field inside an unnamed crater south of Nili Fossae.

Image information: VIS instrument. Latitude 20.6, Longitude 79 East (281 West). 19 meter/pixel resolution.

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

2005-01-01

386

Characterization of Clostridium perfringens isolates from healthy turkeys and from turkeys with necrotic enteritis.  

PubMed

Clostridium perfringens is an important bacterial pathogen, especially in poultry, where it can lead to both subclinical and clinical disease. The aim of this study was to present data on pathological findings at outbreaks of necrotic enteritis (NE) in turkey production in Finland during the period from 1998 to 2012. Furthermore, C. perfringens isolates from healthy and diseased turkeys were characterized and their genetic diversity was investigated using pulsed-field gel electrophoresis (PFGE). Isolates (n = 212) from birds with necrotic gut lesions and from healthy flocks of 30 commercial turkey farms were characterized for the presence of cpa, cpb, iA, etx, cpb2, and cpe and netB genes. A total of 93 C. perfringens isolates, including 55 from birds with necrotic gut lesions and 38 from healthy birds from 13 different farms, were analyzed with PFGE. All contract turkey farmers (n = 48) of a turkey company that produces 99% of domestic turkey meat in Finland were interviewed about background information, management at the farm, and stress factors related to NE outbreaks. Pulsed-field gel electrophoresis analysis with SmaI restriction enzyme resulted in 30 PFGE patterns among the 92 C. perfringens isolates of high diversity. Out of all isolates, 212 (100%) were ?-toxin-positive and one isolate (0.5%) was both ?- and ?2 toxin-positive. Fourteen isolates (6.6%) were necrotic enteritis toxin B (NetB) positive; all were recovered from turkeys with NE. In none of the isolates obtained from healthy turkeys was the netB toxin identified. In conclusion, a high diversity of C. perfringens isolates from turkeys with different health status was shown. All isolates produced ? toxin, whereas only low percentages of isolates carried the netB toxin gene. The role of the netB toxin in NE in turkeys needs to be further investigated. PMID:23776261

Lyhs, U; Perko-Mäkelä, P; Kallio, H; Brockmann, A; Heinikainen, S; Tuuri, H; Pedersen, K

2013-07-01

387

Compression and self-entanglement of single DNA molecules under uniform electric field  

E-print Network

We experimentally study the effects of a uniform electric field on the conformation of single DNA molecules. We demonstrate that a moderate electric field (~200 V/cm) strongly compresses isolated DNA polymer coils into ...

Tang, Jing

388

Complexity and Diversity of Klebsiella pneumoniae Strains with Extended-Spectrum  -Lactamases Isolated in 1994 and 1996 at a Teaching Hospital in Durban, South Africa  

Microsoft Academic Search

b-Lactamase production was investigated in cultures of 25 Klebsiella pneumoniae isolates isolated at a hospital in Durban, South Africa, in 1994 and 1996. Twenty of these isolates gave ceftazidime MIC\\/ceftazidime plus clavulanate MIC ratios of >8, implying production of extended-spectrum b-lactamases (ESBLs), and DNA sequencing identified an ESBL gene (blaTEM-53) in a further two isolates. Pulsed-field gel electrophoresis (PFGE) defined

SABIHA Y. ESSACK; LUCINDA M. C. HALL; DEVADAS G. PILLAY; MARGARET LYNN MCFADYEN; DAVID M. LIVERMORE

2001-01-01

389

Surveillance of Carbapenem-Resistant Pseudomonas aeruginosa Isolates from Puerto Rican Medical Center Hospitals: Dissemination of KPC and IMP18  -Lactamases  

Microsoft Academic Search

During a 6-month period, 37\\/513 (7.2%) Pseudomonas aeruginosa isolates belonging to 13 pulsed-field gel electrophoresis (PFGE) groups from Puerto Rican hospitals were carbapenem nonsusceptible. Seven of 37 isolates from four PFGE groups carried blaIMP-18, and 25\\/37 isolates from seven PFGE groups carried blaKPC. The results indicated the clonal spread of blaKPC-positive P. aeruginosa isolates into several Puerto Rican hospitals and

Daniel J. Wolter; Noha Khalaf; Iraida E. Robledo; Guillermo J. Vazquez; Maria I. Sante; Edna E. Aquino; Richard V. Goering; Nancy D. Hanson

2009-01-01

390

Sleuthing the Isolated Compact Stars  

NASA Astrophysics Data System (ADS)

In the early 1990's, isolated thermally-emitting neutron stars accreting from the interstellar medium were predicted to show up in their thousands in the ROSAT soft X-ray all-sky survey. The glut of sources would provide unprecedented opportunities for probing the equation of state of ultra-dense matter. Only seven objects have been firmly identified to date. The reasons for this discrepency are discussed and recent high resolution X-ray spectroscopic observations of these objects are described. Spectra of the brightest of the isolated neutron star candidates, RX J1856.5-3754, continue to present interpretational difficulties for current neutron star model atmospheres and alternative models are briefly discussed. RX J1856.5-3754 remains a valid quark star candidate.

Drake, J. J.

2004-08-01

391

Heterogeneity of koala retrovirus isolates.  

PubMed

Koala retrovirus (KoRV) is a gammaretrovirus which may induce immune suppression, leukemia and lymphoma in koalas. Currently three KoRV subgroups (A, B, and J) have been reported. Our phylogenetic analysis suggests that KoRV-B and KoRV-J should be classified as the same subgroup. In long terminal repeat (LTR), a KoRV-B isolate has four 17 bp tandem repeats named direct repeat (DR)-1, while a KoRV-J isolate (strain OJ-4) has three 37 bp tandem repeats named DR-2. We also found that the promoter activity of the KoRV-J strain OJ-4 is stronger than that of original KoRV-A, suggesting that KoRV-J may replicate more efficiently than KoRV-A. PMID:24239536

Shimode, Sayumi; Nakagawa, So; Yoshikawa, Rokusuke; Shojima, Takayuki; Miyazawa, Takayuki

2014-01-01

392

Isolated congenital left ventricular diverticulum  

Microsoft Academic Search

Two cases of isolated left ventricular diverticulum are presented. A 12-year-old boy and a 7-year-old girl, both asymptomatic, were admitted to our Department for evaluation of an abnormal electrocardiogram and an abnormal cardiac silhouette, respectively. Both patients had the diagnosis confirmed by cardiac catheterization and angiography and underwent successful surgical correction of the abnormality. We discuss the diagnosis, prognosis, and

G. Pomé; G. Vignati; L. Mauri; M. Morello; A. Figini; A. Pellegrini

1995-01-01

393

Prevalence of Group A Streptococcal Carriers in Asymptomatic Children and Clonal Relatedness among Isolates in Malatya, Turkey  

Microsoft Academic Search

In our study, the prevalence of nasopharyngeal Streptococcus pyogenes was 130 (14.3%) of 909 healthy children. Isolates were found to be susceptible to all antibiotics tested. Pulsed-field gel electrophoresis and arbitrarily primed PCR revealed that 34 (32.4%) of the 105 isolates and 41 (40.6%) of the 101 isolates typed, respectively, were clonally indistinguishable. Streptococcus pyogenes group A streptococcus (GAS) strains

Riza Durmaz; Bengul Durmaz; Mehmet Bayraktar; Ibrahim Halil Ozerol; Mahmut Tayyar Kalcioglu; Elif Aktas; Zeynep Cizmeci

394

Prevalence of Group A Streptococcal Carriers in Asymptomatic Children and Clonal Relatedness among Isolates in Malatya, Turkey  

Microsoft Academic Search

In our study, the prevalence of nasopharyngeal Streptococcus pyogenes was 130 (14.3%) of 909 healthy children. Isolates were found to be susceptible to all antibiotics tested. Pulsed-field gel electrophoresis and arbitrarily primed PCR revealed that 34 (32.4%) of the 105 isolates and 41 (40.6%) of the 101 isolates typed, respectively, were clonally indistinguishable. Streptococcus pyogenes group A streptococcus (GAS) strains

Riza Durmaz; Bengul Durmaz; Mehmet Bayraktar; Ibrahim Halil Ozerol; Mahmut Tayyar Kalcioglu; Elif Aktas; Zeynep Cizmeci

2003-01-01

395

Isolated renal cells and uses thereof  

US Patent & Trademark Office Database

The invention is directed to isolated renal cells, including tubular and erythropoietin (EPO)-producing kidney cell populations, and methods of isolating and culturing the same, as well as methods of treating a subject in need with the cell populations.

2012-11-27

396

Isolation of cellulolytic actinomycetes from marine sediments  

SciTech Connect

The cellulolytic activity of 36 actinomycetes strains isolated from marine sediments was investigated by the cellulose-azure method. Approximately 50% of the isolates exhibited various degrees of cellulolytic activity. 13 references.

Veiga, M.; Esparis, A.; Fabregas, J.

1983-07-01

397

The Victoria Isolation Scale, Form A  

ERIC Educational Resources Information Center

The authors administered the Isolation Symptomatology Questionnaire to persons living in Antarctica who were either well or maladjusted to their environment. Eliminating those items not discriminating between the two groups, the authors constructed a new isolation scale. (SE)

Taylor, A. J. W.; Feletti, Grahame I.

1976-01-01

398

Isolation and characterization of bovine parainfluenza virus type 3 from water buffaloes (Bubalus bubalis) in Argentina  

PubMed Central

Background Parainfluenza virus type 3 (PIV3) was isolated from dairy buffaloes (Bubalus bubalis) naturally affected with respiratory and reproductive clinical conditions. Results Examination of nasal and vaginal swabs collected from 12 diseased buffaloes led to the isolation of three paramyxovirus isolates from two animals. Antigenic, morphological and biological characteristics of these three isolates were essentially similar to those of members of the Paramyxoviridae family. Antigenic analysis by direct immunofluorescence and cross neutralization test placed these isolates together with bovine parainfluenza virus type 3 (BPIV3). Nucleotide and amino acid phylogenetic analysis of partial matrix gene sequences of the buffalo isolates and six field BPIV3 isolates from bovines in Argentina were studied. Buffalo isolates were similar to genotype B (BPIV3b) while the six BPIV3 isolates were similar to genotypes A (BPIV3a) and C (BPIV3c). Conclusions This is the first characterization of BPIV3 in water buffalo. According to the samples analyzed, in Argentina, the genotype B was found in buffalo and the genotypes A and C were found in cattle. PMID:22716217

2012-01-01

399

Molecular characterization of vancomycin-resistant Enterococcus faecium isolated from intensive care units.  

PubMed

To assess the molecular characterization of disseminated vancomycin-resistant enterococci (VRE) in the intensive care units, 546 enterococci isolates were collected from different clinical samples in a prospective observational study. The results showed that a total number of 33 isolates (6 %) were resistant to vancomycin. Most of the VRE isolates 11 (34 %) were isolated from intensive care units (ICUs). 18 (55 %) VRE isolates were obtained from urinary tract infections. The results from pulsed-field gel electrophoresis showed five common types (CT) and 13 single types (ST) among the VRE isolates. The analysis showed two and one major CTs and ST among the ICUs isolates, respectively. Tn1546 transposon was analyzed using ClaI-digested long PCR (L-PCR) RFLP followed by sequencing. The results showed the presence of two different lineages of transposon among the two clonal groups. Lineage 1 with the arrangement of Tn1546 prototype in the first clonal group and the second lineage with 13 kb harboring two insertion sequences, IS1216 V and IS1542. DNA hybridization showed that vanA gene in all VRE isolates, with an exception of one isolate, was present in the same location on the genome. Overall, the results suggest that a few VRE clonal types were disseminated in ICUs in hospitals in Iran which were able to transfer their vanA with high conjugation frequency. PMID:24399362

Talebi, Malihe; Sadeghi, Javad; Pourshafie, Mohammad R

2014-05-01

400

Molecular Characterization of Streptococcus agalactiae Isolated from Bovine Mastitis in Eastern China  

PubMed Central

One hundred and two Streptococcus agalactiae (group B streptococcus [GBS]) isolates were collected from dairy cattle with subclinical mastitis in Eastern China during 2011. Clonal groups were established by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE), respectively. Capsular polysaccharides (CPS), pilus and alpha-like-protein (Alp) family genes were also characterized by molecular techniques. MLST analysis revealed that these isolates were limited to three clonal groups and were clustered in six different lineages, i.e. ST (sequence type) 103, ST568, ST67, ST301, ST313 and ST570, of which ST568 and ST570 were new genotypes. PFGE analysis revealed this isolates were clustered in 27 PFGE types, of which, types 7, 8, 14, 15, 16, 18, 23 and 25 were the eight major types, comprising close to 70% (71/102) of all the isolates. The most prevalent sequence types were ST103 (58% isolates) and ST568 (31% isolates), comprising capsular genotype Ia isolates without any of the detected Alp genes, suggesting the appearance of novel genomic backgrounds of prevalent strains of bovine S. agalactiae. All the strains possessed the pilus island 2b (PI-2b) gene and the prevalent capsular genotypes were types Ia (89% isolates) and II (11% isolates), the conserved pilus type providing suitable data for the development of vaccines against mastitis caused by S. agalactiae. PMID:23874442

Yang, Yongchun; Liu, Yinglong; Ding, Yunlei; Yi, Li; Ma, Zhe; Fan, Hongjie; Lu, Chengping

2013-01-01

401

Human isolates of Listeria monocytogenes in Sweden during half a century (1958-2010).  

PubMed

SUMMARY Isolates of Listeria monocytogenes (n = 932) isolated in Sweden during 1958-2010 from human patients with invasive listeriosis were characterized by serotyping and pulsed-field gel electrophoresis (PFGE) (AscI). Of the 932 isolates, 183 different PFGE types were identified, of which 83 were each represented by only one isolate. In all, 483 serovar 1/2a isolates were distributed over 114 PFGE types; 90 serovar 1/2b isolates gave 32 PFGE types; 21 serovar 1/2c isolates gave nine PFGE types; three serovar 3b isolates gave one PFGE type; and, 335 serovar 4b isolates gave 31 PFGE types. During the 1980s in Sweden, several serovar 4b cases were associated with the consumption of European raw soft cheese. However, as cheese-production hygiene has improved, the number of 4b cases has decreased. Since 1996, serovar 1/2a has been the dominant L. monocytogenes serovar in human listeriosis in Sweden. Therefore, based on current serovars and PFGE types, an association between human cases of listeriosis and the consumption of vacuum-packed gravad and cold-smoked salmon is suggested. PMID:24480252

Lopez-Valladares, G; Tham, W; Parihar, V Singh; Helmersson, S; Andersson, B; Ivarsson, S; Johansson, C; Ringberg, H; Tjernberg, I; Henriques-Normark, B; Danielsson-Tham, M-L

2014-11-01

402

Acinetobacter kookii sp. nov., isolated from soil.  

PubMed

Two Gram-stain-negative, non-fermentative bacterial strains, designated 11-0202(T) and 11-0607, were isolated from soil in South Korea, and four others, LUH 13522, LUH 8638, LUH 10268 and LUH 10288, were isolated from a beet field in Germany, soil in the Netherlands, and sediment of integrated fish farms in Malaysia and Thailand, respectively. Based on 16S rRNA, rpoB and gyrB gene sequences, they are considered to represent a novel species of the genus Acinetobacter. Their 16S rRNA gene sequences showed greatest pairwise similarity to Acinetobacter beijerinckii NIPH 838(T) (97.9-98.4?%). They shared highest rpoB and gyrB gene sequence similarity with Acinetobacter johnsonii DSM 6963(T) and Acinetobacter bouvetii 4B02(T) (85.4-87.6 and 78.1-82.7?%, respectively). Strain 11-0202(T) displayed low DNA-DNA reassociation values (<40?%) with the most closely related species of the genus Acinetobacter. The six strains utilized azelate, 2,3-butanediol, ethanol and dl-lactate as sole carbon sources. Cellular fatty acid analyses showed similarities to profiles of related species of the genus Acinetobacter: summed feature 3 (C16?:?1?7c, C16?:?1?6c; 24.3-27.2?%), C18?:?1?9c (19.9-22.1?%), C16?:?0 (15.2-22.0?%) and C12?:?0 (9.2-14.2?%). On the basis of the current findings, it is concluded that the six strains represent a novel species, for which the name Acinetobacter kookii sp. nov. is proposed. The type strain is 11-0202(T) (?=?KCTC 32033(T)?=?JCM 18512(T)). PMID:23950148

Choi, Ji Young; Ko, Gwangpyo; Jheong, Weonghwa; Huys, Geert; Seifert, Harald; Dijkshoorn, Lenie; Ko, Kwan Soo

2013-12-01

403

Isolation of an alkaloid from Cassia occidentalis  

E-print Network

)ect: Biochemistry THE ISOLATION OF AN ALKALOID FROM CASSIA OCCIDENTALIS A Thesis Larry Ellis Puleo Approved as to style and oontent by: hairman o mmit e M ber Hea o partment Member ACKNOWLEDGEMENT 8 The writer wishes to express hie appreciationt To Dr. B... Scheme Page II Toxicity of various fractions of Cassia occidentalis 20 LIST OF FIGURES Figure 1 Mass Speotrum of the Isolated Compound 2 Infrared Speotrum of the Isolated Com- pound Ultraviolet Absorption Speotrum oi the Isolated Compound...

Puleo, Larry Ellis

2012-06-07

404

Photonic Magnetic Field Sensor  

NASA Astrophysics Data System (ADS)

Small, in-line polarization rotators or isolators to reduce feedback in fiber optic links can be the basis for excellent magnetic field sensors. Based on the giant magneto-optical (GMO) or Faraday effect in iron garnets, they with a magnetic field of a few hundred Gauss, (20 mT) for an interaction length for an optical beam of a few millimeters achieve a polarization rotation or phase shift of 45 deg (1/8 cycle). When powered by a small laser diode, with the induced linear phase shift recovered at the shot noise limit, we have demonstrated sensitivities at the 3.3 nT/Hz1/2 level for frequencies from less than 1 Hz to frequencies into the high kHz range. Through further improvements; an increase in interaction length, better materials and by far the greatest factor, the addition of a flux concentrator, sensitivities at the pT/Hz1/2 level appear to be within reach. We will detail such a design and discuss the issues that may limit achieving these goals.

Wyntjes, Geert

2002-02-01

405

Total main rotor isolation system analysis  

NASA Technical Reports Server (NTRS)

The requirements for a preliminary design study and verification procedure for a total main rotor isolation system at n/rev are established. The system is developed and analyzed, and predesign drawings are created for an isolation system that achieves over 95 percent isolation of all six degrees of freedom.

Halwes, D. R.

1981-01-01

406

Seismic, shock, and vibration isolation - 1988  

SciTech Connect

This book contains papers presented at a conference on pressure vessels and piping. Topics covered include: Design of R-FBI bearings for seismic isolation; Benefits of vertical and horizontal seismic isolation for LMR nuclear reactor units; and Some remarks on the use and perspectives of seismic isolation for fast reactors.

Chung, H. (Argonne National Lab., Argonne, IL (US)); Mostaghel, N. (Univ. of Utah, Salt Lake City, UT (US))

1988-01-01

407

Noninvasive diagnosis of isolated right ventricular infarction  

SciTech Connect

A rare case of isolated right ventricular infarction (RVI) is described. The lack of clinical and electrocardiographic findings characteristic of isolated RVI makes this pathology a diagnostic challenge. The role of the radionuclide scintigraphic procedures as a single possible tool for the diagnosis of isolated RVI is emphasized.