BackgroundThe pathogenicity of Plasmodium falciparum is in part due to the ability of the parasitized red blood cell (pRBC) to adhere to intra-vascular host cell...Full Text Available
BackgroundIndividuals living in malaria endemic areas generally harbour multiple parasite strains. Multiplicity of infection (MOI) can be an indicator of immune status. However,...Full Text Available
Mechanisms for differential regulation of gene expression may underlie much of the phenotypic variation and adaptability of malaria parasites. Here we describe transcriptional variation among culture-adapted...Full Text Available
Cytoadherence or sequestration is essential for the pathogenesis of the most virulent human malaria species, Plasmodium falciparum (P. falciparum). Similar to leukocyte-endothelium...Full Text Available
The methanol and aqueous extracts of 10 plant species (Acacia nilotica, Azadirachta indica, Carissa edulis, Fagaropsis angolensis, Harrissonia abyssinica, Myrica salicifolia, Neoboutonia macrocalyx, Strychnos heningsii, Withania somnifera and Zanthoxylum usambarensis) used to treat malaria in Meru and Kilifi Districts, Kenya, were tested for brine shrimp lethality and in vitro anti-plasmodial activity against chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum (NF54 and ENT30). Of the plants tested, 40% of the methanol extracts were toxic to the brine shrimp (LD5050N. macrocalyx had the highest toxicity to brine shrimp nauplii (LD50 21.04+-1.8mg/ml). Methanol extracts of the rest of the plants exhibited mild or no brine shrimp toxicity (LD50>50mg/ml). The aqueo...
Expression of the nitrate assimilation nir operon in the filamentous, heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120 requires the action of both the...Full Text Available
Effect of strain rate, temperature and grain size in the climb-controlled dislocation creep region for AZ31 magnesium alloy was examined at lower temperature of {proportional_to}473 K. The flow stress was not affected by the difference in grain size. The strain rate sensitivity, m, was obtained 0.14 and 0.2 at low temperatures in high strain rate and at high temperature in low strain rate, respectively. It was found that the notion of effective diffusivity could express the dominant diffusion process during climb-controlled dislocation creep behavior uniquely. (orig.)
General expressions for the interlattice displacements of the A-15 structure compounds are obtained in terms of the strain components making use of the deformation theory. The nature of the interlattice displacements of all the 8 atoms in the unit cell is discussed. It is found that the interlattice displacements occur in such a way that the pair of atoms along any linear chain move in opposite directions with equal magnitudes. Expression for the strain energy of these compounds is developed using deformation theory and this is compared with the strain energy expression from continuum theory to obtain the elastic constants. The theoretical values of the elastic constants fairly agree with the experimental values for V_3Si, V_3Ge and Nb_3Sn. (author).
General expressions for the interlattice displacements of the A-15 structure compounds are obtained in terms of the strain components making use of the deformation theory. The nature of the interlattice displacements of all the 8 atoms in the unit cell is discussed. It is found that the interlattice displacements occur in such a way that the pair of atoms along any linear chain move in opposite directions with equal magnitudes. Expression for the strain energy of these compounds is developed using deformation theory and this is compared with the strain energy expression from continuum theory to obtain the elastic constants. The theoretical values of the elastic constants fairly agree with the experimental values for V3Si, V3Ge and Nb3Sn.
BackgroundPlasmodium falciparum morbid and fatal risks are considerably higher in areas supporting parasite prevalence ≥25%, when compared with low transmission...Full Text Available
BackgroundNaturally acquired immune responses against sexual stages of P. falciparum can reduce the transmission of malaria from humans to mosquitoes. These antigens...Full Text Available
The in vivo sensitivity of Plasmodium falciparum to chloroquine and sulfadoxine/pyrimethamine was evaluated in children under 5 years of age in two areas of southern Nigeria in 1987. A modification...Full Text Available
Plasmodium falciparum, the causative agent of human malaria, invades host erythrocytes using several proteins on the surface of the invasive merozoite, which have been proposed...Full Text Available
BackgroundPregnant women are more susceptible to severe Plasmodium falciparum malaria, which can lead to poor maternal and fetal outcomes. Few data exist on the...Full Text Available
A serodiagnostic test has been developed for the detection of Plasmodium falciparum in infected blood. Using parasite antigens and infected red blood cells from in vitro...Full Text Available
The extensive diversity of Plasmodium falciparum antigens is a major obstacle to a broadly effective malaria vaccine but population genetics has rarely been used to guide vaccine design....Full Text Available
There is growing epidemiological and molecular evidence that ABO blood group affects host susceptibility to severe Plasmodium falciparum infection. The high frequency of common...Full Text Available
The malaria parasite Plasmodium falciparum utilizes molecules present on the surface of uninfected red blood cells (RBC) for rosette formation, and a dependency on ABO antigens has...Full Text Available
Naturally acquired immunity to Plasmodium falciparum malaria in malaria holoendemic areas is characterized by the gradual, age-related development of protection against high-density...Full Text Available
Abs are central to malaria immunity, which is only acquired after years of exposure to Plasmodium falciparum (Pf). Despite the enormous worldwide burden of malaria,...Full Text Available
The rice blast resistance (R) gene Pi-ta mediates gene-for-gene resistance against strains of the fungus Magnaporthe grisea that express avirulent...Full Text Available
This article describes the molecular cloning and expression of a hemolysin gene from a serotype 1 strain of Actinobacillus pleuropneumoniae. The hemolysin was a thermolabile protein with an apparent...Full Text Available
We previously demonstrated the ability to create engineered arteries by carefully controlling the mechanical environment of intact arteries perfused ex vivo, yielding engineered arteries...Full Text Available
Uncoupling protein 2 (UCP2) maps to a region on distal mouse chromosome 7 that has been linked to the phenotypes of obesity and type II diabetes. We recently reported that UCP2 expression is increased...Full Text Available
We cloned and sequenced structural gene choM, which encodes an insecticidally active cholesterol oxidase in Streptomyces sp. strain A19249. The primary translation product was predicted to be a 547-amino-acid...Full Text Available
A chromosomally located β-lactamase gene, cloned and expressed in Escherichia coli from a reference strain of the enterobacterial species Kluyvera cryocrescens,...Full Text Available
The effect of particle/matrix interface debonding on composites consisting of elastic particles and viscoelastic matrix is studied. The interface debonding is represented by a nonlinear cohesive law for the high explosive PBX 9501. The Mori-Tanaka method gives the constitutive relation of the composite in terms of the properties of elastic particles, viscoelastic matrix, and nonlinear cohesive law for interfaces. For the example of a composite with spherical particles subject to hydrostatic tension, simple analytical expressions of the composite stress-strain relation are obtained. The strain rate and temperature have strong effects on the composite behavior. High strain rate and low temperature give high strength of the composite. However, the rate and temperature effects decrease as the ...
Two sequences with homology to a thioredoxin oligonucleotide probe were detected by Southern blot analysis of Anabaena sp. strain PCC 7120 genomic DNA. One of the sequences was shown to code for a protein...Full Text Available
We report that expression of a nearly full-length cDNA clone of the L-A double-stranded RNA virus causes virus loss in a wild-type strain of Saccharomyces cerevisiae. We show that in this system exclusion...Full Text Available
Locomotion is a complex behavior affected by many different brain- and spinal cord systems, as well as by variations in the peripheral nervous system. Recently, we found increased gene expression for EphA4, a gene intricately involved in motor neuron development, between high-active parental strain C57BL/6J and the low-active chromosome substitution strain 1 (CSS1). CSS1 mice carry chromosome 1 from A/J mice in a C57BL/6J genetic background, allowing localization of quantitative trait loci (QTL) on chromosome 1. To find out whether differences in motor neuron anatomy, possibly related to the changes in EphA4 expression, are involved in the motor activity differences observed in these strains, motor performance in various behavioral paradigms and anatomical differences in the ventral roots ...
When the foundations of the building are designed and worked, the prediction calculation of immediate settlement of the building exercised practically is to calculate assuming the earth is a linear elastic body, but the actual stress-strain relationship of the earth is nonlinear and rigidity of the earth becomes lower as strain (or stress) increases. Hence in order to grasp the actual settling behavior of the earth, it is necessary to elucidate the nonlinear relationship between stress and strain. In this article, a prediction method of building settlement is introduced which uses an analytical technique of the multi-layered earth by the linear elasticity theory and takes into consideration strain dependency of rigidity of the earth. Part of the conclusion is as follows which has been obtained by studying the settling behaviors observed in examples of vertical loading tests of the pile foundations and ...
BackgroundPlasmodium falciparum is the most malignant agent of human malaria. It belongs to the taxon Laverania, which includes other ape-infecting Plasmodium...Full Text Available
With the spread of chloroquine resistant Plasmodium falciparum the control of malaria has become increasingly complex. In recent years, particular concern has arisen over how best to prevent malaria...Full Text Available
Abstract Strains of Pseudomonas syringae are effective in controlling postharvest diseases of citrus fruits, and antagonistic activity has been correlated with in vitro production of lipodepsipeptides. Additionally, biocontrol agents can induce a range of defence mechanisms of resistance in citrus tissue that result in a broad spectrum of metabolic modifications, such as systemic acquired resistance, induced systemic resistance and production of reactive oxygen species. The aim of this study was to evaluate the expression of syringomycin (syrB1) and syringopeptin (sypA) synthetase genes from P.syringae pv. syringae biocontrol strains in vitro on different culture media and in vivo on citrus fruits (Citrus sinensis cv. Tarocco) during the interaction with Penicillium digitatum by quantitati...
Several lines of evidence are presented that indicate that the level of tetracycline resistance of Esherichia coli strains harboring plasmid pBR322 varies according to whether the SOS system of the host bacteria has been induced. These include use of strains in which the SOS system is expressed constitutively (lexA def.), is thermoinducible (recA441) or noninducible (lexA ind-), or is highly repressed (multiple copies of lexA+). Similar induction was observed with the product of another plasmid gene, beta-lactamase. The amounts of extractable plasmid DNA were also increased by SOS induction, and we propose that the SOS-induced increases in levels of tetracycline resistance and beta-lactamase activity are due to an increased plasmid copy number.
The expression of motor activity levels in response to novel situations is under complex genetic and environmental control. Several genetic loci have been implicated in the regulation of this behavioral phenotype, but their relationship to epigenetic and epistatic interactions is relatively unknown. Here, we report on a quantitative trait locus (QTL) on mouse chromosome 1 for novelty-induced motor activity in the open field, using chromosome substitution strains derived from a high active host strain (C57BL/6J) and a low active donor strain (A/J). The QTL for open field (horizontal distance moved) peaked at the location of Kcnj9, however, QTL detection was initially masked by an interplay of both grandparent genetic origin and genetic co-factors influencing behavior on chromosome 1. Our fi...
Mesenchymal stem cells (MSCs) are a potential source of smooth muscle cells (SMCs) for constructing tissue-engineered vascular grafts. However, the details of how specific combinations of vascular microenvironmental factors regulate MSCs are not well understood. Previous studies have suggested that both mechanical stimulation with uniaxial cyclic strain and chemical stimulation with transforming growth factor {beta}1 (TGF-{beta}1) can induce smooth muscle markers in MSCs. In this study, we investigated the combined effects of uniaxial cyclic strain and TGF-{beta}1 stimulation on MSCs. By using a proteomic analysis, we found differential regulation of several proteins and genes, such as the up-regulation of TGF-{beta}1-induced protein ig-h3 (BGH3) protein levels by TGF-{beta}1 and up-regulation of calponin 3 protein level by cyclic strain. At the gene expression level, BGH3 was induced by TGF-{beta}1, ...
The aim of the present study is to identify and characterize the antimalrial agents from traitional Sudanese medicinal plants. 49 plants parts representing 26 species from 15 families were extracted and screened for their in vitro antimalrial activity using P. falciparumstrain 3D7 which is chloroquine sensitive and Dd2 strain which is chloroquine resistant and pyrimethamine sensitive.The plant species investigated exhibited diverse botanical families. They includes Annonaceae, Aristolochiaceae, Asteraceae, Balantiaceae, Caesalpiniceae, Celasteraceae, Cucurbitaceae, Fabaceae, Graminae, Meliaceae, Myrtaceae, Polygonaceae, Rubiaceae, Rutaceae, and simaroubaceae. The evaluation of these plants for their antimalarial activity and their effect on lymphocyte proliferation was carried out. 57 extracts were tested on the chloroquine sensitive strain (3D7). Where 34 extracts (59%) exhibited significant activity ...
The metabolism of pentose-phosphate was investigated in Plasmodium falciparum-infected normal and glucose-6-phosphate dehydrogenase (G6PD)-deficient human red blood cells in vitro. 5'-Phosphoribosyl-1-pyrophosphate...Full Text Available
To evaluate the reactivity of the recombinant proteins expressed in Escherichia coli strain BL21(DE3), a Western blot assay was performed by using a panel of 78 serum samples obtained,...Full Text Available
The gene encoding N epsilon-(indole-3-acetyl)-L-lysine synthetase, iaaL, from Pseudomonas savastanoi was localized within a 4.25-kilobase EcoRI fragment derived from pIAA1 of oleander strain EW 2009....Full Text Available
We analyzed 43 CTX-M-15–producing Escherichia coli isolates and 6 plasmids encoding the blaCTX-M-15 gene from Canada, India, Kuwait, France, Switzerland,...Full Text Available
A chromosome-encoded β-lactamase gene, cloned and expressed in Escherichia coli from Kluyvera georgiana reference strain CUETM 4246-74 (DSM 9408), encoded the...Full Text Available
Previous research utilizing the AcB/BcA recombinant congenic strains (RCS) of mice mapped provisional quantitative trait loci (QTLs) for the psychostimulant effects of nicotine to multiple regions on chromosomes 7, 11, 12, 14, 16, and 17. The current study was designed to confirm these QTLs in an A/J (A)??C57Bl/6J (B6) F2 cross and a panel of B6.A chromosome substitution strains (CSS). The panel of B6.A CSS consists of 21 strains, each carrying a different A/J chromosome on a B6 background. The A??B6 F2, CSS, A, and B6 mice were tested for sensitivity to the effects of nicotine on locomotor activity using a computerized open-field apparatus. In A??B6 F2 mice two QTLs were identified which confirm those previously observed in the AcB/BcA RCS. Significant differences in the expression of ...
Summary Background There is a need for new artemisinin-based combination therapies that are convenient, effective, and safe. We compared the efficacy and safety of pyronaridine-artesunate with that of artemether-lumefantrine for treatment of uncomplicated P falciparum malaria. Methods This phase 3, parallel-group, double-blind, randomised, non-inferiority trial was undertaken in seven sites in Africa and three sites in southeast Asia. In a double-dummy design, patients aged 3-60 years with uncomplicated P falciparum malaria were randomly assigned in a 2:1 ratio to receive pyronaridine-artesunate once a day or artemether-lumefantrine twice a day, orally for 3 days, plus respective placebo. Randomisation was done by computer-generated randomisation sequence in blocks of nine by study centre....
We report a search for small RNAs (sRNAs) in the low-GC, gram-positive human pathogen Streptococcus pneumoniae. Based on bioinformatic analyses by Livny et al. (J. Livny, A. Brencic, S. Lory, and M. K. Waldor, Nucleic Acids Res. 34:3484-3493, 2006), we tested 40 candidates by Northern blotting and confirmed the expression of nine new and one previously reported (CcnA) sRNAs in strain D39. CcnA is one of five redundant sRNAs reported by Halfmann et al. (A. Halfmann, M. Kovacs, R. Hakenbeck, and R. Bruckner, Mol. Microbiol. 66:110-126, 2007) that are positively controlled by the CiaR response regulator. We characterized 3 of these 14 sRNAs: Spd-sr17 (144 nucleotides [nt]; decreased in stationary phase), Spd-sr37 (80 nt; strongly expressed in all growth phases), and CcnA (93 nt; induced by competence stimulatory peptide). Spd-sr17 and CcnA likely fold into structures containing single-stranded regions between hairpin ...
Using the complete genome of Plasmodium falciparum 3D7 which has 14 chromosomes as an example, we have examined the distribution functions for the amount of C or G and A or T consecutively...Full Text Available
BackgroundArtemisinin-based combination therapy, currently considered the therapy of choice for uncomplicated Plasmodium falciparum malaria in endemic countries,...Full Text Available
BackgroundImproving the understanding of childhood malarial anaemia may help in the design of appropriate management strategies.MethodsA...Full Text Available
The development of rapid and specific diagnostic tests to identify individuals infected with malaria is of paramount importance in efforts to control the severe public health impact of this disease....Full Text Available
BackgroundAn artemisinin-based combination therapy, artesunate (AS) plus sulphadoxine-pyrimethamine (SP), was compared to SP monotherapy to provide evidence of further treatment...Full Text Available
BackgroundIn sub-Saharan Africa, Plasmodium falciparum malaria in pregnancy presents an enormous diagnostic challenge. The epidemiological and clinical relevance...Full Text Available
Merozoite surface proteins have been implicated in the initial attachment to the host red blood cell membrane that begins the process of invasion, an important step in the life cycle of the malaria...Full Text Available
BackgroundObtaining single parasite clones is required for many techniques in malaria research. Cloning by limiting dilution using microscopy-based assessment for parasite growth...Full Text Available
Cerebral malaria is the most severe complication of human infection with Plasmodium falciparum. It was shown that Plasmodium berghei ANKA-induced cerebral malaria was...Full Text Available
BackgroundBlood group O has been significantly associated with increased placental malaria infection in primiparae and reduced risk of infection in multiparae in the Gambia, an area...Full Text Available
Using the phasmid vector pSL5, the genomic DNA fragment of T. aquaticus YT1 which contained the thermostable DNA polymerase (Taq-polymerase) gene was cloned. The BglII fragment of this genome locus was subcloned in the BamHI site of the pUC19 plasmid. To optimize the Taq-polymerase gene expression in E. coli cells, the gene was cloned in the correct reading frame regarding the initiation ATG codon of the pPR-TGATG-1 expression vector. The gene expression in this vector was controlled by the phage lambda PR promoter and the temperature-sensitive phage lambda repressor. We used PCR to amplify the short 5'-end fragment of the Taq-polymerase gene coding for the part into which an artificial SacI site was introduced. This site has been used for cloning the PCR product into the pPR-TGATG-1 vector, and the missing gene part was cloned into the KpnI site of the PCR product from the natural cloned gene. The cells of the E. coli ...
This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.
Abstract Alkali tolerance and the mechanism of microcystin (MC) degradation were investigated in the MC-degrading bacterial species, Sphingopyxis sp. C-1, to better understand the increased MC degradation under the alkaline conditions that arise during the disappearance of water blooms. MC-degrading bacteria harbour mlrA, mlrB and mlrC that encode MC-degrading enzymes. Sphingopyxis sp. C-1 also possesses these genes, as well as the mlrD gene that has been assumed to encode MC and its degradation transporter. This study demonstrated that MC degradation activity was promoted by the intermittent addition of microcystin-LR (MCLR) to cultures of strain C-1. That the expression of mlrA, mlrB and mlrC is induced by MCLR also was indicated, whereas that of mlrA and mlrB is induced by the MCLR degr...
Metabolic engineering of photosynthetic organisms is required for utilization of light energy and for reducing carbon emissions.Control of transcriptional regulators is a powerful approach for changing cellular dynamics, because a set of genes is concomitantly regulated. Here, we show that overexpression of a group 2 ? factor, SigE, enhances the expressions of sugar catabolic genes in the unicellular cyanobacterium, Synechocystis sp. PCC 6803. Transcriptome analysis revealed that genes for the oxidative pentose phosphate pathway and glycogen catabolism are induced by overproduction of SigE. Immunoblotting showed that protein levels of sugar catabolic enzymes, such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glycogen phosphorylase, and isoamylase, are increased. Glycogen levels are reduced in the SigE-overexpressing strain grown under light. Metabolome analysis revealed that metabolite levels of the TCA cycle and ...
The usual method of introducing engineers to the concept of dislocations and their role in plastic flow is to compare an estimate of the theoretical strength of solid (of order {micro}/30 where {micro} is the shear modulus) and the observed strength of either single crystals ({mu}/10{sup 4}) or practical engineering material such as structural steels where the yield stress in shear is of order {mu}/10{sup 3}. However, if one considers the problem in reverse, one can consider the accumulation of dislocations as an important mechanism by which one can produce engineering materials in which the strength level approaches the theoretical strength. If one assumes that the flow stress can be expressed in terms of te mean free path between stored dislocations or as the square root of the global dislocation density, then one can see the influence of dislocation density in a diagrammatic form. It is clear that the strengthening by dislocation accumulation due to large ...
We have previously shown that avian reovirus (ARV) #sigma#A and #sigma#NS proteins possess dsRNA and ssRNA binding activity and suggested that there are two epitopes on #sigma#A (I and II) and three epitopes (A, B, and C) on #sigma#NS. To further define the location of epitopes on #sigma#A and #sigma#NS proteins and to further elucidate the biological functions of these epitopes by using monoclonal antibodies (MAbs) 62, 1F9, H1E1, and 4A123 against the ARV S1133 strain, the full-length and deletion fragments of S2 and S4 genes of ARV generated by polymerase chain reaction (PCR) were cloned into pET32 expression vectors and the fusion proteins were overexpressed in Escherichia coli BL21 strain. Epitope mapping using MAbs and E. coli-expressed deletion fragments of #sigma#A and #sigma#NS of the ARV S1133 strain, synthetic peptides, and the cross reactivity of MAbs to heterologous ARV ...
To assess the influence of a live attenuated oral vaccine against porcine post-weaning colibacillosis (PWC) induced by enterotoxigenic Escherichia coli (ETEC) on mucosal lymphoid cell CD45 isoforms expression, experimental group of weaned pigs (n=6) was immunized orally with F4ac+ non-ETEC strain (day 0) and challenged with F4ac+ ETEC strain 7 days latter. Non-immunized ETEC-infected pigs (n=6) served as control. All pigs were killed on post-challenge day 7. The small intestine was excised for isolation of jejunal lamina propria (JLP) and ileal Peyer's patch (IPP) lymphocytes and immunohistochemical studies. The results obtained by immunophenotyping of isolated cells show that the proportion of CD45RA+ and CD45RC+ JLP, but not IPP, cells were higher in the non-ETEC-immunized ETEC-infected pigs versus non-immunized infected. Additionally, while CD45RA+ JLP cells increased only slightly, the expression of ...
Two plasmids which express either nearly intact or truncated filamentous hemagglutinin (FHA) from Bordetella pertussis and which are marked with a tetracycline resistance (Tcr) gene were transformed into Salmonella dublin SL1438, an aroA deletion mutant intended for use as an attenuated oral vaccine against salmonellosis. These S. dublin recombinants, when fed to mice, induced serum immunoglobulin, immunoglobulin M (IgM), and sometimes IgA antibody responses to FHA and S. dublin. In addition, IgA antibodies against FHA were found in gut wash fluids. S. dublin carrying pDB2300, a multicopy plasmid encoding truncated FHA protein, induced a better antibody response than did S. dublin carrying pDB2000, a low-copy-number plasmid encoding full-sized FHA. Administration of tetracycline to mice enhanced the stability of recombinant plasmids, and tetracycline-treated mice developed higher anti-FHA titers. Although neither strain examined is suitable for ...
Biosorption is presented as an alternative choice to traditional physicochemical means for removing toxic metals from groundwater and wastewaters. Removal of lead (Pb) from solutions was studied using Escherichia coli (parental) and Vitreoscilla hemoglobin (VHb)-expressing E. coli (transformed) cells. Pb biosorption was increased in bacterial hemoglobin-expressing E. coli cells grown in Luria broth B containing different concentrations of Pb{sup 2+}. The maximum Pb{sup 2+} biosorption of transformed and parental cells was determined to be 612 and 370 {mu}g Pb/g biomass, respectively. The inhibitory effect of Pb{sup 2+} on the parental strain was determined at 10 ppm. However, in transformed cells, Pb{sup 2+} was lethal at 100 ppm. The optimum aeration required for the transformed cells was lower than that for the parental strain on a growth yield basis. A linear correlation was established between the ...
In order to achieve efficient d-lactic acid fermentation from a mixture of xylose and glucose, the xylose-assimilating xylAB operon from Lactobacillus pentosus (PXylAB) was introduced into an l-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum (?ldhL1-xpk1::tkt-?xpk2) strain in which the phosphoketolase 1 gene (xpk1) was replaced with the transketolase gene (tkt) from Lactococcus lactis, and the phosphoketolase 2 (xpk2) gene was deleted. Two copies of xylAB introduced into the genome significantly improved the xylose fermentation ability, raising it to the same level as that of ?ldhL1-xpk1::tkt-?xpk2 harboring a xylAB operon-expressing plasmid. Using the two-copy xylAB integrated strain, successful homo-d-lactic acid production was achieved from a mixture of 25?g/l xylos...
The response regulator protein is a core element of two-component signaling pathway. In this study, we investigated functions of BRRG-1 of Botrytis cinerea, a gene that encodes a putative response regulator protein, which is homologous to Rrg-1 in Neurospora crassa. The BRRG-1 gene deletion mutant ?Brrg1-62 was unable to produce conidia. The mutant showed increased sensitivity to osmotic stress mediated by NaCl and KCl, and to oxidative stress generated by H2O2. Additionally, the mutant was more sensitive to the fungicides iprodione, fludioxonil, and triadimefon than the parental strain. Western-blot analysis showed that the Bos-2 protein, the putative downstream component of Brrg-1, was not phosphorylated in the ?Brrg1-62. Real-time polymerase chain reaction assays showed that expression ...
Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization ...
This study describes the role of "inflammatory" oxidized (Ox) phospholipids in regulation of rahU (PA0122) expression and biofilm formation in Pseudomonas aeruginosa (383) wild type (rahU+) and rahU mutant (rahU-) strains. Functional analysis of RahU protein from P. aeruginosa in presence of Ox-phospholipids show: (a) LysoPC modulates RahU gene/and protein expression in rahU+ cells; (b) rahU promoter activity is increased by lysoPC and inhibited by PAPC, Ox-PAPC and arachidonic acid; the latter inhibitory effect can be reversed by lysoPC, which was enzymatically derived from PAPC; (c) biofilm formation increased in rahU- cells as compared to rahU+; and (d) inhibition of rahU promoter activity by PAPC and AA (but not lysoPC) showed significantly augmented biofilm formation in rahU+ but not ...
BackgroundThe Plasmodium falciparum pre-erythrocytic stage candidate vaccine RTS,S is being developed for protection of young children against...Full Text Available
BackgroundThe present study evaluated the SD Bioline Malaria Ag 05FK40 (SDFK40), a three-band RDT detecting Plasmodium falciparum-specific parasite lactate dehydrogenase...Full Text Available
BackgroundSeveral studies have demonstrated the efficacy of artemisinin-combination therapy (ACT) across malaria zones of the world. Fixed dose ACT with shorter courses and fewer...Full Text Available
The entire genome of rabies virus vaccine strain Flury-LEP-C, a Chinese variant of the rabies virus vaccine strain Flury-LEP, was sequenced. The overall length of the genome of Flury-LEP-C strain was...Full Text Available
A strain of Neurospora crassa was isolated by training the mould to grow on media containing high concentrations of Co2+. This strain, the CoRstrain, exhibited...Full Text Available
In experiments designed to detect new mutations affecting hemoglobin, we irradiated the male or female parent in reciprocal crosses of two mouse strains that differ in alleles at the hemoglobin (Hba, Hbb) loci as well as at five other specific loci. Offspring were analyzed for hemoglobin properties (electrophoretic pattern, solubility, crystal pattern), serum albumin differences, erythrocyte lysis, reticulocyte count, and external appearance. Five hemoglobin variants were found among the mutants. In three, the genetic contribution from the irradiated father was not expressed with regard to the #alpha#-chain; one carried a tandem duplication (the first known case in the mouse) involving Hbb; and one probably resulted from double nondisjunction of chromosome 7. The finding that major chromosome aberratios can mimic hemoglobin mutations indicates the need, in similar experiments, to follow F_1 screening with thorough cytogenetic analysis. The ...
An on-line cell disruption system for at-line monitoring of the intracellular concentration of recombinant human superoxide dismutase (rhSOD) in a genetically modified Escherichia coli strain, HMS174(DE3) (pET11a/rhSOD), in bioreactor cultivations is described. The sampled bacteria were disrupted on-line by rapid mixing with a nonionic detergent. The recombinant protein content of the lysed bacterial sample was quantitated by a subsequent surface plasmon resonance biosensor with a specific monoclonal antibody. Extraction efficiency of the monitoring system was optimized with respect to the flow rate ratio of the cell suspension and the detergent at relevant cell densities with the aim to attain rapid monitoring. Monitoring was demonstrated for a shake flask culture and a glucose-limited fed-batch cultivation. The results are compared with a traditional enzyme-linked immunosorbent assay method showing a correlation coefficient of R2 = 0.97. Extraction efficiency of ...
First results on the effects of strain on transient enhanced diffusion and deactivation of As-implanted ultrashallow junctions are presented. A significant effect of strain on the magnitude and timescale of transient enhanced diffusion is observed, which is consistent with the stabilization of interstitial-type defects by tensile strain. Our results show no significant impact of strain on As electrical activity during the deactivation timescale accessed in this study.
The neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene structure. The murine {alpha}7 shares amino acid identity of 99% and 93% with the rat and human {alpha}7 ...
Bombyx mandarina nucleopolyhedrovirus (BomaNPV) is a variant of Bombyx mori nucleopolyhedrovirus (BmNPV). BomaNPV S1 strain has been reported to be significantly less virulent than the BmNPV T3 strain via the oral infection route in B. mori larvae, but other features of S1 including budded virus (BV) infectivity and virus propagation in cultured cells are still unknown. In this study, we compared BV infectivity of S1 and T3 in B. mori larvae and cultured cells. Larval bioassays by intrahemocoelic BV injection revealed that the median lethal dose of S1's BV was approximately three times lower than that of T3. In addition, S1 produced more BVs and occlusion bodies (OBs) in the hemolymph of B. mori larvae compared with T3. Furthermore, we observed that the locomotion was enhanced earlier and the median lethal time was shorter in S1-infected larvae compared with those in T3-infected larvae. Western blot analysis of S1- and T3-infected BmN cells ...
Delta-hemolysin of coagulase-negative staphylococcal strains was immunologically identical to delta-hemolysin of Staphylococcus aureus (Newman) but distinct from delta-hemolysin from a canine strain...Full Text Available
Muscular fatigue in the training athlete or military recruit has been hypothesized to cause increased bone strain that may contribute to the development of a stress fracture. Under normal circumstances, muscles exert a protective effect by contracting to reduce bending strains on cortical bone surfaces. In vivo strain studies in dogs show that muscle fatigue following strenuous exercise elevates bone strain and changes strain distribution. However, a similar experiment has yet to be performed in humans. The purpose of this work was to test the hypothesis in humans that strenuous fatiguing exercise causes an elevation in bone strain. It was also hypothesized that this elevation is greater in younger people than in older people due to the decline in muscle strength and endurance that normally occurs with age. To test these hypotheses, strain ...
Observations made during biochemical and toxicological studies of the housefly, in which the WHO standard reference (SR) strain was used as a standard, indicated that this strain differs from other...Full Text Available
Strains in multivalley semiconductors can destroy the strict equivalence of the valleys that is demanded by cubic symmetry. Significant changes in the properties of a semiconductor may result. A proposed implementation of quantum computing with donor atoms in silicon would suffer from alterations of the donor wave functions caused by strains that are produced by fabrication processes. Deliberately straining the silicon to an extent that removed all but one valley from participation in the lowest donor state, would prevent further changes in the wave function by strain. The strain required can be achieved with established technology for depositing silicon on SiGe alloys. (author)
A {lambda}gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. ...
A #lambda#gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. ...
In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herval mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Stimulation of macrophage cell line with herval extracts with the treatments of recombinant interferon-{gamma} resulted in increased nitric oxide synthesis in a dose-dependent ...
In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herbal mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts (Him-I, Him-II) which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Some fractions of Him-I and Him-II increased the proliferation of bone marrow cells irradiated {gamma}-ray(4Gray). Stimulation of macrophage cell line with herval ...
... charge carriers in strained p-Ge in crossed electric and magnetic fields was studied by means of measurements of spontaneous radiation intensity. ...
Ether extracts of cultures of 29 strains representing 6 species of Bacillus, and of individual strains of Escherichia coli, Aerobacter aerogenes, and Pseudomonas...Full Text Available
A new area-wide pest control strategy using the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), genetically transformed with a conditionally lethal gene, is under development. Conditional lethality of several transgenic pink bollworm strains was demonstrated in a series of laboratory rearing experiments. Pink bollworms were transformed with genetic constructs using the RIDL technology (Release of Insects with a Dominant Lethal gene) for development of an autocidal biological control system for possible supplement or replacement of radiation based sterile insect release. LA1124 is a lethal construct controlled by a tetracycline repressible transactivator protein (tTA), in which binding of tTA to its specific target sequence tetO drives production of more tTA. In the absence of tetracycline, this leads to lethality by high expression of tTA. When tetracycline is present, tTA does not bind tetO, and so the positive ...
Newly hatched chicks were dosed orally with a Salmonella typhimurium wild-type strain, an S. enteritidis wild-type strain, and a genetically defined S. enteritidis aroA vaccine candidate, strain CVL30....Full Text Available
High strain fatigue problem in steam turbine. Cyclic stress strain hysteresis loops and stress relaxation behaviour in 16 h dwell period tests. Variation of stress and strain during tests under nominally strain controlled conditions. Definition of test conditions and of criteria for crack initiation and failure. Comparison of reverse bend and push pull failure data. (orig.) 891 RW/orig. 892 RKD.
A prototype hydride storage bed, using LaNi{sub 4.25}Al{sub 0.75} as the storage material, was fitted with strain gages to measure strains occurring in the stainless steel bed vessel caused by expansion of the storage powder upon uptake of hydrogen. The strain remained low in the bed as hydrogen was added, up to a bed loading of about 0.5 hydrogen to metal atom ratio (H/M). The strain then increased with increasing hydrogen loading ({approximately} 0.8 H/M). Different locations exhibited greatly different levels of maximum strain. In no case was the design stress of the vessel exceeded.
Effect of strain and temperature on high temperature deformation properties of an alpha + beta titanium alloy Ti-6Al-4V has been investigated in the temperature range 800 to 910 deg. C by using the method of cross head speed cycling. On the basis of flow stress strain rate-strain rate sensitivity data and microstructural studies of the undeformed and deformed regions of tensile test pieces, both strain introduced hardening and softening effects were observed during the course of deformation which could be associated with grain coarsening and refining respectively. (author)
Ethnobotanical and chemotaxonomical studies for antiparasitic activity of Colombian Annonaceae were carried out. In vitro antiprotozoal activity of 36 extracts obtained from six different species was determined against promastigotes of three Leishmania species, epimastigotes of Trypanosoma cruzi and both chloroquine sensitive (F32) and resistant (W2) Plasmodium falciparum. Cytotoxic activity was evaluated in U-937 cells. Active extracts were selected according their selectivity index (SI). Extracts from Annona muricata, Rollinia exsucca, Rollinia pittieri and Xylopia aromatica were active against Leishmania spp. and Trypanosoma cruzi showing IC50 values lower than 25mg/ml. Hexane extract from Rollinia pittieri leaves was the most selective against Trypanosoma cruzi and Leishmania spp. (IS=...
Hole mobility changes under uniaxial and combinational stress in different directions are characterized and analyzed by applying additive mechanical uniaxial stress to bulk Si and SiGe-virtual-substrate-induced strained-Si (s-Si) p-MOSFETs (metal-oxide-semiconductor field-effect transistors) along (110) and (100) channel directions. In bulk Si, a mobility enhancement peak is found under uniaxial compressive strain in the low vertical field. The combination of (100) direction uniaxial tensile strain and substrate-induced biaxial tensile strain provides a higher mobility relative to the (110) direction, opposite to the situation in bulk Si. But the combinational strain experiences a gain loss at high field, which means that uniaxial compressive strain may still be a better choice. The mobility enhancement of SiGe-induced strained p-MOSFETs ...
Shewanella oneidensis MR-1 is a model environmental organism that possesses diverse respiratory capacities, including the ability to reduce soluble Cr(VI) to sparingly soluble, less toxic Cr(III). Effective bioremediation of Cr-contaminated sites requires knowledge of the molecular mechanisms and regulation of heavy metal resistance and biotransformation by dissimilatory metal-reducing bacteria. Towards this goal, our ERSP-funded work is focused on the identification and functional analysis of genes/proteins comprising the response pathways for chromate detoxification and/or reduction. Previous transcriptomic profiling and whole-cell proteomic analyses implicated the involvement of a functionally undefined DNA-binding response regulator (SO2426) and a putative azoreductase (SO3585) in the chromate stress response of MR-1. Here we describe a detailed functional analysis of SO2426 and SO3585 in order to begin to understand the role of these proteins in the cellular response to chromate. ...
Reactions on the ionizing radiation of 14 Cladosporium cladosporioides strains were studied. Only 5 of them displayed radiotropizm. The ability of C. cladosporioides strains 4 and 5 with positive radiotropizm and museum C. cladosporioides strain 396 and its alb-mutant SM without positive radiotropizm to destruct radioactive particles of Chernobyl and explosion origin was studied. Two ways of radioactive particles destruction by C. cladosporioides were established, one of them is a direct way by fungal overgrowth of hot particles and the second one an indirect way only by fungal metabolites. Mycelium of the studied C. cladosporioides strains sorbed radionuclides from radioactive particles during cultivation on the liquid and agarized media. No certain inclinations of the individual strains to accumulation of radionuclides 137Cs or 152Eu were ascertained. PMID:12664550
Mediterranean mariculture uses imported strains of marine phytoplankton, raising questions of ecological risk and ability to adapt to local conditions for mass culture outdoors. In this context, we report here on the mass-culture potential and chemical composition of six strains of Prasinophyceae (five strains of Tetraselmis sp. and one Pyramimonas sp.) isolated from a Greek coastal lagoon. Proximate composition had a pattern of 10?20% ash, 35?65% protein, 6?10% lipids, and 25?45% other organics including carbohydrates. The amino acid profiles were typical for the marine representatives of the class. All strains had a high PUFA content with dominant the ?3 fraction in four of them. The fatty acid profiles indicated a Tetraselmis strain with high EPA (14%) and a Pyramimonas strain with high...
Nineteen fungal strains having an ability to oxidize elemental sulfur in mineral salts medium were isolated from deteriorated sandstones of Angkor monuments. These fungi formed clearing zone on agar medium supplemented with powder sulfur due to the dissolution of sulfur. Representative of the isolates, strain THIF01, was identified as Fusarium solani on the basis of morphological characteristics and phylogenetic analyses. PCR amplification targeting 16S rRNA gene and analyses of full 16S rRNA gene sequence indicated strain THIF01 harbors an endobacterium Bradyrhizobium sp.; however, involvement of the bacterium in the sulfur oxidation is still unclear. Strain THIF01 oxidized elemental sulfur to thiosulfate and then sulfate. Germination of the spores of strain THIF01 was observed in a liqui...
Abstract:- Campylobacter jejuni-is the leading cause of bacterial diarrheal illness worldwide. Many strains are now becoming multidrug resistant. Apple-based edible films containing carvacrol and cinnamaldehyde were evaluated for bactericidal activity against antibiotic resistant and susceptible-C. jejuni-strains on chicken. Retail chicken breast samples inoculated with D28a and H2a (resistant strains) and A24a (a sensitive strain) were wrapped in apple films containing cinnamaldehyde or carvacrol at 0.5%, 1.5%, and 3% concentrations, and then incubated at 4 or 23 C for 72 h. Immediately after wrapping and at 72 h, samples were plated for enumeration of viable-C. jejuni. The antimicrobial films exhibited dose- and temperature-dependent bactericidal activity against all strains. Films with ...
A factor produced by plerocercoids of the tapeworm Spirometra mansonoides is similar to human growth hormone (hGH) in that it stimulates body growth, binds to hGH receptors, cross-reacts with anti-hGH antibodies, and has lactogenic and insulin-like activities. The purpose of this study was to determine whether plerocercoid growth factor (PGF) is similar to hGH in expressing diabetogenic activity in the genetically obese (ob/ob) mouse. To determine an effective dose for use in the obese mice, the ability of daily injections of PGF to stimulate growth of phenotypically normal mice of the same strain was assessed in a 10-day weight gain assay. Injections of PGF stimulated a dose-dependent weight gain (r = 0.83) and 25 ng eq/day of PGF stimulated a response not significantly different from that produced by 100 micrograms of bovine growth hormone/day. Diabetogenicity was assessed using fasting blood glucose and glucose tolerance tests in obese mice ...
Viscoelasticity of gel films prepared from solvent-soluble constituents without ash of coal using the mixed solvent of carbon disulfide and N-methyl-2-pyrrolidinone (CS2-NMP) was measured to study the network structure of the constituents. In experiment, Upper Freeport coal and Zao Zhuang coal were used as specimens. Viscoelasticity of various gels with different weight fractions of solvent was measured by creep measurement under a fixed load and stress-strain analysis under variable loads. In the 2nd and 3rd creep measurements, although no large changes in elastic strain and viscoelastic strain were found, viscous strain gradually decreased with an increase in viscosity. In the case of small weight fraction of solvent, small viscous strain and viscoelastic strain were found, while slightly large elastic strain was found. It was thus ...
The genome sequence of the Mamavirus, a new Acanthamoeba polyphaga mimivirus strain, is reported. With 1,191,693 nt in length and 1,023 predicted protein-coding genes, the Mamavirus...Full Text Available
Strong inhibitory effects of the anionic surfactant linear alkylbenzene sulfonate (LAS) on four strains of autotrophic ammonia-oxidizing bacteria (AOB) are reported. Two Nitrosospira...Full Text Available
Mouse genetic resources include inbred strains, recombinant inbred lines, chromosome substitution strains, heterogeneous stocks, and the Collaborative Cross (CC). These resources were generated through...Full Text Available
Virulent strains of Newcastle disease virus ([NDV] also known as avian paramyxovirus type 1) can be discriminated from low-virulence strains by the presence of multiple basic amino acid residues at...Full Text Available
BackgroundThere has been considerable effort to discover plant-derived antibacterials against methicillin-resistant strains of Staphylococcus aureus (MRSA) which...Full Text Available
Although genetic engineering techniques for baker's yeast might improve the yeast's fermentation characteristics, the lack of scientific data on the survival of such strains in natural environments...Full Text Available
A total of 262 strains of Staphylococcus aureus isolated from the mammary gland of dairy cows were examined for the production of alpha-hemolysin. Strains were cultured in a liquid medium of casein...Full Text Available
1. The penicillinases formed by penicillinase-constitutive mutant strains from two closely related varieties (749 and 6346) of Bacillus licheniformis have been isolated, characterized...Full Text Available
Plasmid transfer between strains of Bacillus thuringiensis subsp. israelensis was studied under a range of environmentally relevant laboratory conditions in vitro,...Full Text Available
Some strains of Bradyrhizobium japonicum have the ability to catabolize indole-3-acetic acid (IAA). Examination of this catabolism in strain 110 by in vivo experiments has revealed an enzymatic activity...Full Text Available
An outbreak with a multiresistant Klebsiella pneumoniae (MRKP) strain among seven patients admitted to the adult intensive care unit (ICU) of a regional teaching hospital in The Netherlands...Full Text Available
A new strain of mouse hepatitis virus (MHV) was isolated from pooled gut suspensions from an epizootic of lethal enteritis in newborn mice. Negative-contrast electron microscopy showed an abundance...Full Text Available
A technique is described for displaying distinct tissue layers of large blood vessel walls as well as measuring their mechanical strain. The technique is based on deuterium double-quantum-filtered (DQF)...Full Text Available
OBJECTIVES. In this study we tested the association between occupational stress--as measured by job demands, decision latitude, and job strain--and hypertension in a population of 1396 Black and White...Full Text Available
Scytalidium thermophilum isolates in culture, as well as the endogenous strain(s) in mushroom compost, were inactivated at 70°C. This temperature was used to pasteurize composts...Full Text Available
Dramatic differences in the height of lima beans (Phaseolus lunatus L.) treated with two different Rhizobium strains were studied. Lima beans were grown in Perlite...Full Text Available
A series of cyclic strain controlled tests have been carried out at 600/sup 0/C on three high temperature austenitic iron-based alloys, AISI type 316 stainless steel, Alloy 800 H and Sandvik 253 MA. The tests were carried out under constant total strain control using a constant strain rate of 0.005 s/sup -1/. By considering the changes in modulus throughout the life of each specimen it was found that damage evolution could be successfully predicted as a function of plastic strain range despite the fact that each alloy had been chosen because of a different stress response at 600/sup 0/C. Although each alloy accumulated fatigue damage in a similar manner the longer lives of Sandvik 253 MA and Alloy 800 H at a given total strain range were due to a smaller plastic strain component and a reduced stage I crack propagation rate. In the 253 MA alloy, slip was ...
Campylobacter is one of the leading causes of food-borne gastroenteritis and has a high prevalence in poultry. Campylobacter jejuni subsp. jejuni 327 is a subspecies...Full Text Available
BackgroundEscherichia coli strain EL350 contains chromosomally integrated phage lambda Red recombinase genes enabling this strain to be used for modifying the sequence...Full Text Available
The hypothesis, that a decrease in metabolic rate mediates the life span prolonging effect of caloric restriction (CR), was tested using two strains of mice, one of which, C57BL/6, exhibits...Full Text Available
The soil-isolated strain XP was identified as Rhodococcus erythropolis. R. erythropolis XP could efficiently desulfurize benzonaphthothiophene, a complicated model sulfur compound that...Full Text Available
In an attempt to establish if cross protection can be induced by different strains of Haemophilus parasuis, three groups of 12 gnotobiotic pigs were immunized each with an aluminum hydroxide adsorbed...Full Text Available
A strain from human diarrhea originally identified as Campylobacter mucosalis (NCTC 12408) was examined by using 64 phenotypic characters. The similarity of this strain to 297 isolates of Campylobacter,...Full Text Available
Rhesus monkeys were infected with strains of Schistosoma mansoni from Puerto Rico, St Lucia, Brazil, and Tanzania. Monkeys were killed 11-14 weeks after exposure to 600-650 cercariae....Full Text Available
Mice were killed 7, 11, 19, and 27 weeks after infection with strains of Schistosoma mansoni from Puerto Rico, Brazil, St Lucia, and Tanzania. The percentage recovery of adult worms...Full Text Available
BackgroundThe purpose of this study was to examine the influence of proximal retrograde intramedullary nail position on proximal femoral strain, since stress risers...Full Text Available
Arsenic is one of the most important global environmental pollutants. Here we show that the cyanobacterium Synechocystis sp. strain PCC 6803 contains an arsenic and antimony resistance...Full Text Available
BackgroundType A1 Clostridium botulinum strains are a group of Gram-positive, spore-forming anaerobic bacteria that produce a genetically, biochemically, and biophysically...Full Text Available
In the cyanobacterium Anabaena sp. strain PCC 7120, open reading frames (ORFs) alr3026, alr3027, and all3028 encode a tripartite ATP-independent...Full Text Available
The full-length gene encoding the histone deacetylase (HDAC)-like amidohydrolase (HDAH) from Bordetella or Alcaligenes (Bordetella/Alcaligenes) strain...Full Text Available
Strain rate effects for the high strength, metastable beta-titanium alloy Ti-8Mo-8V-2Fe-3Al are assessed in terms of tensile and fracture toughness behavior. It is shown that as the strain rate increases the yield strength, ultimate tensile strength, and ductility also increase. As a result of the decrease in the amount of intergranular fracture as the strain rate is increased, the dynamic fracture toughness values K/sub Id/ are greater than those obtained under static conditions as given by K/sub Q/.
High temperature deformation behavior of an alpha + beta titanium alloy Ti-3Al-4V has been investigated at 910 deg. C. by using the method of cross head speed cycling. On the basis of flow stress, strain rate and strain rate sensitivity data, the alloy was found to exhibit strain hardening at this temperature which resulted in degradation in superplastic properties of the alloy. A high beta-phase volume fraction and grain-growth in both alpha and beta phases were considered responsible for the observed hardening effect. (author)
runs are necessary, provision shall be made for expansion joints, motion of the units, or similar compensation to ensure that no excessive strains are ...
The strain gradient crystal plasticity theory is applied to study the deformation of planar single crystal with a void under a nominally uniaxial tension. The crystal theory assumes elevated strain hardening due to slip gradients and has a constitutive length scale. The effects of the void size with respect to the constitutive length scale on the single crystal deformation are investigated.
Megasphaera elsdenii is a lactate-fermenting, obligately anaerobic bacterium commonly present in the gastrointestinal tracts of mammals, including humans. Swine M. elsdenii strains were previously shown to have high levels of tetracycline resistance (MIC = 64->256 micro g/ml) and to carry mosaic (re...
A cosmid library of DNA from colicin Js-sensitive enteroinvasive Escherichia coli (EIEC) strain O164 was made in colicin Js-resistant strain E. coli VCS257, and colicin...Full Text Available
Comparison of the embryolethality of monomeric "2"3"9Pu injected at 9 days of gestation demonstrated that the sensitivity of Charles River CD strain was greater than that of Hilltop Wistar rats. Subsequent comparisons showed that rats derived from the Hilltop Fischer strain were more sensitive than the Wistar and, although not directly compared, more sensitive than the CD.
A mutant strain of Saccharomyces cerevisiae (D10-ER1) has been isolated after a two-step mutagenesis of strain 4059-358D (SUC 1) using ethyl methane sulfonate. Cells of this new strain produced a level...Full Text Available
We have measured the oxygen positions in LaNiO{sub 3} films to elucidate the coupling between epitaxial strain and oxygen octahedral rotations. The oxygen positions are determined by comparing the measured and calculated intensities of half-order Bragg peaks, arising from the octahedral rotations. Combining ab initio density-functional calculations with these experimental results, we show how strain systematically modifies both bond angles and lengths in this functional perovskite oxide.
Two clinical strains of Escherichia coli (2138) and Enterobacter cloacae (7506) isolated from the same patient in France and showing resistance to extended-spectrum...Full Text Available
The dissimilatory metal reducing bacterium Shewanella sp. strain HN-41 was first reported to produce novel photoactive As-S nanotubes via reduction of As(V) and S(2)O(3)(2-) under anaerobic conditions. Here we report the draft genome sequence and annotation of strain HN-41. PMID:21868804
This paper describes the anelastic strain recovery and the strain hardening of amorphous metals and presents the experimental result that creep deformation is represented by a viscoelastic model consisting of rheological elements. Materials studied were 80Pd--20Si, 80Fe--13P--7C, and 60 Cu--40 Zr. (DLC)
Synthetic gene networks can be used to control gene expression and cellular phenotypes in a variety of applications. In many instances, however, such networks can behave unreliably due to gene expression...Full Text Available
The effect of growth phase on expression of virulence-associated factors was studied by Northern hybridization in an M1T1 clinical isolate of Streptococcus pyogenes. Expression of M...Full Text Available
Aim—To study p53 expression in relation to proliferative status in normal and nondysplastic, dysplastic and malignant lesions of the oral mucosa.Method—The...Full Text Available
BackgroundCells dynamically adapt their gene expression patterns in response to various stimuli. This response is orchestrated into a number of gene expression modules consisting...Full Text Available
BackgroundMicroRNAs (miRNAs) are non-coding RNAs that regulate gene expression by binding to the messenger RNA (mRNA) of protein coding genes. They control gene expression by either...Full Text Available
The protein kinase CK2 (formerly casein kinase II) is thought to be involved in light-regulated gene expression in plants because...Full Text Available
We develop a statistical framework to study the relationship between chromatin features and gene expression. This can be used to predict gene expression of protein coding genes, as well as microRNAs....Full Text Available
The aim of this study was to survey the expression of an embryonic cytokine gene, MK, in the normal organs and neoplastic tissues of adults. Northern analysis showed that MK mRNA was exclusively expressed...Full Text Available
Gene expression is a fundamentally stochastic process, with randomness in transcription and translation leading to significant cell-to-cell variations in mRNA and protein levels. This variation...Full Text Available
HypothesisBiomarkers, commonly expressed in breast cancer cells, may be correlated with their expression in breast skin of the same subjects.MethodsThe...Full Text Available
PurposeTo analyze the expression of apoptosis and cell proliferation molecules in pterygium tissues of Chinese patients.MethodsThirty-three pterygia...Full Text Available
Cis-acting regulatory sequences are required for the proper temporal and spatial control of gene expression. Variation in gene expression is highly heritable and a significant determinant...Full Text Available
The local strain and texture in Al interconnect wires have been investigated using white and monochromatic x-ray microbeams on the MHATTCAT undulator beam line at the Advanced Photon Source. Intergrain and intragrain orientations were obtained with ~0.01 degree sensitivity using white beam measurements on wide Al pads (~100 Mu-m) and thin (2 Mu-m) Al wires. Orientation changes of up to 1 degree were found within individual grains of the (111) textured Al interconnects. Deviatoric strain measurements indicate small intragranular strain variations, but intergranular strain variations were found to be quite large.
Strain transient dip tests have been conducted on two commercial heats of Alloy 800 at 922 K. Tests were conducted on both a servo-controlled hydraulic machine and a specially designed dip test machine. Using measured maximum strain changes during dips allowed unambiguous definition of a kinematic variable. The several other methods of interpreting dip test data by attempting to measure strain rates shortly after the unloading decrements were found not to be satisfactory. The nature of the instantaneous unloading strains and the strain transients following unloading are also discussed in terms of the mechanisms of deformation in Alloy 800. 9 figures, 3 tables.
The present study describes the screening of five lactic acid bacteria (LAB) for use as probiotics based on their competitive adhesion and production of antagonistic substances against some fish pathogens. A reduction of adhesion of all pathogenic strains tested was obtained with three of the LAB strains (Lactococcus lactis subsp. lactis CLFP100, Lactococcus lactis subsp. cremoris CLFP102 and Lactobacillus curvatus CLFP150). With the exception of fish pathogens Flavobacterium psychrophilum and Renibacterium salmoninarum that were not inhibited by LAB strains, production of antagonistic compounds by all tested LAB was observed against at least one of the indicator strains. Based on mucus adhesion, competitive exclusion, and suppression of fish pathogen growth, the selected LAB strains can b...
Summary The antigenic relationship between the phocine distemper virus (PDV) strain causing the epidemic in 2002 and the PDV strain of 1988, canine distemper virus from two dogs and one marten, and one measles virus strain was investigated in vivo and in vitro using monospecific polyclonal and monoclonal antibodies directed against five different proteins of canine or phocine distemper virus (N, P, M, F, H). Epitopic mapping revealed no difference between the PDV strains causing the epidemics in 1988 or 2002. However, the use of these antibodies allowed discrimination between different morbilliviruses including a vaccine strain of canine distemper virus. The major differences among the investigated morbilliviruses were found in the H protein.
A new evaluation of the 1% time strain limit for creep strength and the isochronous stress/strain relationship was to be undertaken for the type 800 alloy, based on up to date experimental data. After the evaluation of the 1% time strain limit curves and time fracture curves of individual melts, multilinear regression analyses were made to clear up the relationship between parameters of the creep behaviour such as creep strength, 1% time strain limit and time fracture strain on the one hand and metallurgical parameters such as C, Ti, Al, Ni, Cr contents or grain size and type of manufacture, on the other hand. Based on the knowledge gained from these calculations, new limits were determined for HTR material specifications for variants of the 800 alloy of the Rk, NT, DE, and HT type. (orig./DG).
Ga{sub 0.6}In{sub 0.4}P/(Al{sub 0.8}Ga{sub 0.2}){sub 0.4}In{sub 0.6}P strain-compensated multiple quantum wells (SCMQW) and Ga{sub 0.5}In{sub 0.5}P/(Al{sub 0.4}Ga{sub 0.6}){sub 0.5}In{sub 0.5}P unstrained MQW were grown by MOVPE to investigate the shift of photoluminescence (PL) peak wavelength and the carrier lifetime caused by strain effect in SCMQW. The PL peaks of SCMQW and unstrained MQW were 608 and 628 nm, respectively. From the rocking curve of SCMQW, it indicated that the active layers of SCMQW were not zero net strain. The residual strain caused the emission intensity of SCMQW to be about four times weaker than that of unstrained MQW. The carrier lifetimes of SCMQW and unstrained MQW were measured to be 3 and 6.02 ns, respectively. It was conjectured that the residual strain in SCMQW induced a decrease in the carrier lifetime by a factor of two with respect to that of ...
Ga_0_._6In_0_._4P/(Al_0_._8Ga_0_._2)_0_._4In_0_._6P strain-compensated multiple quantum wells (SCMQW) and Ga_0_._5In_0_._5P/(Al_0_._4Ga_0_._6)_0_._5In_0_._5P unstrained MQW were grown by MOVPE to investigate the shift of photoluminescence (PL) peak wavelength and the carrier lifetime caused by strain effect in SCMQW. The PL peaks of SCMQW and unstrained MQW were 608 and 628 nm, respectively. From the rocking curve of SCMQW, it indicated that the active layers of SCMQW were not zero net strain. The residual strain caused the emission intensity of SCMQW to be about four times weaker than that of unstrained MQW. The carrier lifetimes of SCMQW and unstrained MQW were measured to be 3 and 6.02 ns, respectively. It was conjectured that the residual strain in SCMQW induced a decrease in the carrier lifetime by a factor of two with respect to that of unstrained MQW.
A mutation to tetracycline sensitivity in a resistant strain of Streptococcus pneumoniae was shown by several criteria to be due to a point mutation in the conjugative o(cat-tet) element found in the chromosomes of strains derived from BM6001, a clinical strain resistant to tetracycline and chloramphenicol. Strains carrying the mutation were transformed back to tetracycline resistance with the high efficiency of a point marker by donor deoxyribonucleic acids from its ancestral strain and from nine other clinical isolates of pneumococcus and by deoxyribonucleic acids from Group D Streptococcus faecalis and Group B Streptococcus agalactiae strains that also carry conjugative tet elements in their chromosomes. It was not transformed to resistance by tet plasmid deoxyribonucleic acids from either gram-negative or gram-positive species, except for one that carried ...
Bacterial attachment-effacement (att-eff) is emerging as an important virulence characteristic common to both enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC). The contribution of the plasmid-encoded EPEC adherence factor to the production of mucosal lesions and diarrhea was investigated in gnotobiotic piglets. Bacterial att-aff in the intestinal mucosa of piglets infected with plasmid-cured EPEC strain E2348/69 (O127) was indistinguishable from that in piglets infected with the parent strain, but the distribution of lesions was different; it occurred in the small intestines of 6 of 7 piglets infected with the parent strain compared with only 2 of 11 (P = 0.006) infected with the plasmid-cured strain. Plasmid-encoded factors in EPEC and EHEC strains did not appear to contribute to bacterial competition with normal gut microflora. Of 13 ...
In this study, isothermal torsion tests were carried out on magnesium AZ31B alloy under constant strain rate conditions, in the range of 250 to 400 C at 0.01, 0.1, and 1.0 s{sup -1}. Alloy flow stress dependence on strain rate and temperature can be described by a power law with activation energy of 130 kJ/mol. Microstructural examination of hot deformed samples shows very fine recrystallized grains decorating grain boundaries of larger gains in the form of a necklace. These fine grains are produced by dynamic recrystallization at the grain boundaries of original grains. Microstructure evolution, based on samples quenched at different strain levels, indicates that increasing deformation strain has little effect on recrystallized grain size but widens the recrystallized region, with full recrystallization achieved at a certain high strain level. Recrystallized grain size increases ...
Axial strain characterization was completed for a Nb{sub 3}Sn conductor from Lawrence Livermore National Lab used in a transverse stress test of a cable-in-conduit conductor. The effect of axial strain on the critical current of the LLNL Nb{sub 3}Sn test strand was measured at magnetic fields from 8 T to 22 T. The conductor specifications are shown in Table 3, and the measured data are shown in Table 4. The data are presented graphically in Figs. 5 through 7. The I{sub c} and J{sub c} values are based on an electric field criterion (E{sub c}) of 2 {mu}V/cm. The zero-strain 12 T value of J{sub c} at 12 T was 0.39 GA/m{sup 2}. The irreversible strain limit was quite high, 1.0 strain, and the compressive prestrain was relatively low at 0.27%. Fracture strain was 1.10%.
The low-cycle fatigue properties of the ferritic-martensitic steels MANET I and II and F82H-mod, have been investigated at a temperature of 200 C. The strain-controlled fatigue has been performed with strain ranges between 0,4% and 1,0% and at a strain rate of 8.10{sup -4} s{sup -1}. The steel F82H-mod, is characterised by a higher plastic strain amplitude compared to MANET I and II. Some of the specimens have beenirradiated with a 104 MeV {alpha}-particle beam. The homogeneous implantation of 400 appm He leads to a hardening of the material. At the beginning of the fatigue tests the stress response of the irradiatedspecimens is higher compared to the unirradiated specimens. In general, thematerial shows softening during fatigue. The softening of irradiated material, which is fatigue tested with a high total strain amplitude, is higher than that of the unirradiated material. The ...
Infant mice were used to measure the amount of fluid accumulation (enterosorption) in the intestinal tract after oral inoculation of a porcine strain of enteropathogenic Escherichia coli (K88-+, Ent-+). Significant reduction in the amount of fluid found in the intestinal tract was observed if the mice were first inoculated with a K88-possessing, non-enterotoxigenic strain of E. coli. The protection provided is thought to be due to specific competition for attachment sites on cells of the small intestine. PMID:1095492
Superplastic deformation behavior in an alpha + beta titanium alloy Ti-3A-4V has been investigated by using the method of cross head speed cycling in the temperature range 750-910 /sup 0/C. On the basis of flow stress-strain rate-strain rate sensitivity data, the alloy was found to be superplastic in the entire temperature range studied. Optimum superplasticity was observed in the strain-rate range 3 x 10/sup -5/ sec./sup -1/ to 6 x 10/sup -5/ and at the highest temperature of 910 deg. C. (author).
Simplified strain-based fracture mechanics equations, established for external surface cracked pipelines subjected to an external bending load, are presented and used in probabilistic assessment of a pipeline girth weld. The model takes into account several parameters, such as variation in crack depth, crack length, internal pressure and material hardening. The critical strain from ductile tearing in the cracked pipeline is found by using the tangency criterion. The reliability problem is solved using first and second order reliability methods for different pipe dimensions and load levels.
A plane stress constitutive relation is developed for laminate composites undergoing matrix cracking and therefore displaying significant nonlinear stress-strain behavior. The constitutive relation is similar in some respects to a phenomenological theory of plasticity in that it is fit to data from uniaxial tests. The constitutive equations are specialized to brittle matrix composites (especially CMCs) in the form of cross-piles and quasi-isotropic laminates. Several problems involving stress redistribution at holes and notches due to nonlinear stress-strain behavior are investigated with the aid of the constitutive law.
During spring and autumn, the total number of amoebae and the number of acanthamoeba species able to grow at 37 degrees C were determined in six thermally polluted factory discharges and the surrounding surface waters. The isolated Acanthamoeba strains were studied for growth in axenic medium, cytopathic effect in Vito cell cultures, and virulence in mice. Although more amoebae were isolated in autumn, the number of Acanthamoeba species was lower than in spring, when the percent of pathogenic strains among the isolates was highest. Higher concentrations of amoebae were found in warm discharges, and more virulent strains occurred in thermal discharges than in surface waters.
The effect of elastic and plastic strains on the magnetic properties of ferrite-pearlite steels has been studied. It has been shown that the sensitivity to elastic-tensile and bending strains is four to five times greater for remnant magnetization than for coercive force. In order to determine the degree of cold plastic deformation of high-carbon steels, a two-parametric testing technique based on the use of remnant magnetization and coercive force was suggested. An MMT-2 device was recommended for measurement of the required parameters.
In the tests, the effects of the overhang length on the pipe whip behavior of the pipe-restraints system were studied by measuring the strains and deformations of the test pipe and restraints, and the restraints forces. The equation for predicting the maximum strain at the outer surface of the pipe was derived using a static equilibrium condition. The calculated maximum strains at the outer surface of the pipe agree fairly well with experimental data. The dynamic response analysis of the pipe-restraints system was conducted by the finite element program ADINA. The applicability of the ADINA program to the pipe whip analysis is made clear through this analysis.
White beam Laue micro-diffraction was performed on directionally solidified, single-crystal Mo pillars in the as-grown state, after focused ion beam (FIB) milling and after pre-straining. The Laue diffraction peaks from the as-grown pillars are very sharp and show no broadening, similar to those from single-crystal Si wafers. Significant broadening and streaking of the peaks occurred after FIB milling and pre-straining, indicative of the damage these treatments induce in the nearly perfect crystal structure of the directionally solidified Mo pillars.
The study is concerned with the combined effect of high pressure and shear strain on the properties of the A-15 intermetallics Nb3Sn and Nb3Al0.75Ge0.25. The properties discussed are the superconducting transition temperature, the width and intensity of the X-ray diffraction lines, and the width and shape of the Mossbauer absorption lines. It is shown that the combined effect of high pressure and shear strain leads to an intense generation of defects in polycrystalline specimens; the size of the ordered regions does not exceed 300 A even under the least severe conditions. 5 references.
Micro-compression specimens, 1O-15{mu}m in diameter by 20-30{mu}m in height, were produced from individual parent grains in a polycrystalline U-13at%Nb shape-memory alloy using the focused ion beam (FIB) technique. The specimens were tested in a nanoindentation instrument with a flat diamond tip to investigate stress-strain behavior as a function of crystallographic orientation. The results are in qualitative agreement with a single-crystal accommodation strain (Bain strain) model of the shape-memory effect for this alloy.
The effects of eight chemicals on the inactivation rate of ultraviolet radiation on the colony building capabilities of two strains of Saccharomyces cervisae - a wild type strain and a mutant deficient in excision repair - were studied. The insecticide methoxychlor, the herbicide 2,4-dichlorophenoxyacetic acid, the fungicide pentachlorophenol and its metabolite tetrachlorohydroquinone, as well as the chemicals acrylonitrile and 2,3-dichloro-1-propene have no significant impact on the effects of UV radiation in Saccharomyces cerevisae. Depending on the concentration, trichloroethylene increases the sensitivity to UV radiation. The herbicide paraquat provides efficient protection against UV radiation at concentrations where a toxic effect cannot be observed even without UV. The results were rather similar for both strains. (orig.).
There are currently no accepted industry standards for the tensile strain limits of girth welds. This paper investigated the behavior of girth welds with buried defects subjected to high longitudinal strains caused by soil movement. A strain design methodology based on a crack driving method was used to examine the factors influencing stain limits along with a constraint-sensitive fracture mechanics approach. No strength undermatching was used in the welds, and the defect location had no influence on crack driving force. The weld joint was assumed to have uniform tensile properties. A 3D finite element (FE) model was used to simulate pipe behavior. Symmetric boundary conditions were imposed on the symmetry planes, and uniform remote axial displacement was applied as the primary loading. Automated data processing routines were developed to extract and analyze the data. The crack driving force was computed directly from a ...
The development of several DDT-resistant strains of Anopheles atroparvus is described. They were selected by larval treatment only (RL), selection of larval and adult females (RLAF),...Full Text Available
By tests about pipe failure under extreme bending, moment at cross sections affected by circumferential cracks, admissible strains for securing the integrity in the area of a flow link are indicated. These are 7% for austenic and ferritic materials in the undisturbed cross section. From d/t-ratios of 20 onwards the strains are limited by pipe bulging on the pressure-load side. In this connection, circumferential flaws do not have any influence on the behaviour on the strained side, when their expansion does not exceed the investigated limitis of <60 circumferential expansion and crack depth of 0,3 t. (orig.)
The extent (density and diameter) of the native (preexisting) collateral circulation in healthy tissues and the capacity of collaterals to enlarge/remodel in obstructive arterial disease are important...Full Text Available
Sandia National Laboratories has erected a research oriented, 34- meter diameter, Darrieus vertical axis wind turbine near Bushland, Texas. This machine, designated the Sandia 34-m VAWT Test Bed, is equipped with a large array of strain gauges that have been placed at critical positions about the blades. This manuscript details a series of four-point bend experiments that were conducted to validate the output of the blade strain gauge circuits. The output of a particular gauge circuit is validated by comparing its output to equivalent gauge circuits (in this stress state) and to theoretical predictions. With only a few exceptions, the difference between measured and predicted strain values for a gauge circuit was found to be of the order of the estimated repeatability for the measurement system.
To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3?mg/kg, and 1, 3 and 10?mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain diffe...
... rate on the tensile properties of SA-106 carbon steel pipe, in support of analysis and experimental modeling of postulated pipe whip in nuclear ...
The growth and properties of Si{sub 1{minus}y}C{sub y} and Si{sub 1{minus}x{minus}y}Ge{sub x}C{sub y} alloys pseudomorphically strained on Si(001) will be reviewed. Although the bulk solubility of carbon in silicon is small, epitaxial layers with more than 1 at.% C can be fabricated. The relation between substitutional and interstitial carbon incorporation will be presented. Substitutionally incorporated C atoms allow strain manipulation, including the growth of strain-free or inversely strained Si{sub 1{minus}x{minus}y}Ge{sub x}C{sub y} layers. The mechanical properties, microscopic structure, thermal stability, as well as the influence of C atoms on band structure will be discussed.
The effect of different media and pH on the formation of amylase by Aspergillus oryzae EI 212 is described. Depending upon the composition of the medium and growth...Full Text Available
A strain of Pseudomonas syringae was recently identified as the cause of a new foliar blight of impatiens. The bacterium was resistant to copper compounds, which are used on a variety...Full Text Available
Individual strains of the plant pathogenic bacterium Pseudomonas syringae vary in their ability to produce toxins, nucleate ice, and resist antimicrobial compounds. These phenotypes...Full Text Available
Toxigenic Clostridium sordellii strains are increasingly recognized to cause highly lethal infections in humans that are typified by a toxic shock syndrome (TSS). Two glucosylating toxins, lethal toxin (TcsL) and hemorrhagic toxin (TcsH) are believed to be important in the pathogenesis of TSS. While non-toxigenic strains of C. sordellii demonstrate reduced cytotoxicity in vitro and lower virulence in animal models of infection, there are few data regarding their behavior in humans. Here we report a non-TSS C. sordellii infection in the context of a polymicrobial bacterial cholangitis. The C. sordellii strain associated with this infection did not carry either the TcsL-encoding tcsL gene or the tcsH gene for TcsH. In addition, the strain was neither cytotoxic in vitro nor lethal in a murine...
This study was focused on the possibility to inactivate thermosensitive Listeria monocytogenes ATCL3C 7644 and thermoresistant 56 Ly strain by Na-Chlorophyllin (Na-Chl)-based photosensitization in vitro and on the surface of packaging. Comparative analysis of antimicrobial efficiency of photosensitization with conventional surface cleaning was performed. Data indicate that both Listeria strains, after incubation with Na-Chl and following illumination (l=400nm, 20mWcm-2), were inactivated by 7 log in vitro. This treatment cleaned both Listeria strains from packaging surfaces. Comparative analysis indicates that washing with water diminishes pathogens by less than 1 log, 200ppm Na-hypochlorite by 1.7 log, Na-Chl-based photosensitization by 4.5 log. Listeria biofilms were totally removed from...
Enterococci are mostly isolated from urinary tract infections (UTIs). Increasing antibiotic resistance affects the success rate in empirical treatment, thus makes antibiotic susceptibility tests important. The aim of this study was to determine the species distribution and resistance patterns of Enterococcus strains isolated from urine samples to antibacterial agents including fosfomycin in a teaching hospital, Istanbul. The identification of 100 Enterococcus strains were determined by using conventional methods and API 20 Strep (bioMerieux France). The susceptibility testing was performed by disk diffusion and Etest. The majority of isolates were E. faecalis (67%), followed by E. faecium (33%). The ratio of E. faecalis to E. faecium was 2.03/1. E. faecalis and E. faecium strains were resi...
Polymer matrix composites are presently used in many fields due to their excellent mechanical properties such as high specific strength and stiffness. However, not much is known of these composites' response to impact loading, which usually occurs at strain rates much higher than the strain rates used to measure the quasi-static mechanical properties of materials. The use of static properties in the study of structures that undergo dynamic loading can produce excessive design weight or cause unexplained and untimely failure. The studies included in this dissertation provide the results of Split Hopkinson Pressure Bar experiments to determine the ultimate compressive strength and strain of composites at high strain rates. Most researchers are using specimens with different dimensions and geometry. For this reason, it is difficult to compare results of tests done by different people. Herein, the Split ...
In the present article, the study to examine the ability of free-living amoebae (FLA) to serve as vectors of cryptosporidia is presented. Ten strains of different free-living amoebae of the FLA collection of the Parasitology Lab at Koblenz were cultivated in the presence of Cryptosporidium parvum oocysts. After phagocytosis and ingestion, the oocysts could be found in food vacuoles within the cytoplasm of the trophozoites of two different FLA strains. The uptake and the transport of the oocysts within the trophozoites could be demonstrated in an Acanthamoeba sp. (group II) strain (maximum, three oocysts; average, one oocyst) as well as in a Thecamoeba quadrilineata strain (maximum, 15 oocysts; average, eight oocysts), with the help of light microscopy. We found that these free-living amoeb...
The varestraint cracking test was carried out to assess the hot cracking tendency of alloy 800 at different welding conditions and augmented strain levels. The test results revealed that the hot cracking susceptibility of alloy 800 increases with increasing the heat input and augmented strain levels. This emphasizes the role of constraint either internally induced or externally applied to the welded structure. A cracking threshold or the minimum augmented strain ([epsilon][sub min]) below which no hot cracking takes place has been found to be 0.25 for alloy 800. Also, the Critical Strain Rate to Time (CSS) required to cause cracking was found to be 6.42x10[sup -3] sec[sup -1] at welding condition of 100 Amp, 13 Volt and 140 mm/min. (author).
The varestraint cracking test was carried out to assess the hot cracking tendency of alloy 800 at different welding conditions and augmented strain levels. The test results revealed that the hot cracking susceptibility of alloy 800 increases with increasing the heat input and augmented strain levels. This emphasizes the role of constraint either internally induced or externally applied to the welded structure. A cracking threshold or the minimum augmented strain (#epsilon#_m_i_n) below which no hot cracking takes place has been found to be 0.25 for alloy 800. Also, the Critical Strain Rate to Time (CSS) required to cause cracking was found to be 6.42x10"-"3 sec"-"1 at welding condition of 100 Amp, 13 Volt and 140 mm/min. (author).
Two strains of Rhizobium: Rhizobium Tropici and Mesorhizobium Ciceri nodulating respectively common bean and chickpea were treated by gamma irradiation (60Co) source. Radiosensibility analysis showed that 800 Gy was the biggest dose supported by these two strains. We isolated gamma irradiated resistant strain in order to select mutant of them which can supported salt stress and phosphorus deficiency. Salinity analysis showed that Mesorhizobium Ciceri 835 strain, can tolerate up to 18g/l (273 mM NaCl) of salt, whereas, their irradiation mutants tolerate salinity up to 33g/l (564mM. NaCl) Rhizobium Tropici CIAT899 can survive at 20g/l (342 mM) either for control strain or mutants. Analysis of phosphorus deficiency showed that either Rhizobium Tropici CIAT899, or Mesorhizobium Ciceri 835 can survive in medium without phosphore. Our results permit us to screen mutants tolerant to these ...
Results of investigation on the effect of microstructure and deformation conditions (temperature and strain rate) on flow stress and critical strain in two phase #alpha# + #beta# titanium alloy Ti-6Al-5Mo-5V-1Cr-1Fe is presented in the paper. The alloy is deformed or torsional plastometer at temperature range 1073-1173 K and at the strain rate #epsilon# = 0.04-4.0 s"-"1. Sequential deformation at 1173 K at the strain rate of 0.4 s"-"1 was also performed with holding times in the range 1-100 s. The fraction of dynamically and metadynamically recrystallized #beta# phase was determined on the basis of results of sequential deformation test. Microstructure was examined using LM and TEM techniques. (author)
Studies were carried out on the decolorization of textile azo dyes by newly isolated halophilic and halotolerant bacteria. Among the 27 strains of halophilic and halotolerant bacteria isolated from effluents of textile industries, three showed remarkable ability in decolorizing the widely utilized azo dyes. Phenotypic characterization and phylogenetic analysis based on 16S rDNA sequence comparisons indicate that these strains belonged to the genus Halomonas. The three strains were able to decolorize azo dyes in a wide range of NaCl concentration (up to 20%w/v), temperature (25-40degreeC), and pH (5-11) after 4 days of incubation in static culture. They could decolorize the mixture of dyes as well as pure dyes. These strains also readily grew in and decolorized the high concentrations of dy...
As adulterated and substituted Chinese medicinal materials are common in the market, therapeutic effectiveness of such materials cannot be guaranteed. Identification at species-, strain- and locality-levels,...Full Text Available
Brucella melitensis is a Gram-negative coccobacillus bacteria belonging to the Alphaproteobacteria subclass. It is an important zoonotic pathogen that causes brucellosis, a disease affecting sheep, cattle, and sometimes humans. The B. melitensis strain M5-90, a live attenuated vaccine cultured from the B. melitensis virulent strain M28, has been an effective tool to control brucellosis in goats and sheep in China. Here we report the complete genome sequences of B. melitensis M28 and M5-90, strains with different virulence backgrounds, which will serve as a valuable reference for future studies. PMID:21478357
Many high-strain-rate compression measurements (2000 per second) using a specially designed split Hopkinson pressure bar (SHPB) for the plastic-bonded explosive PBX9501 have been reported in the literature, but there is a sparsity of data for a United Kingdom polymer-bonded explosives (PBX) known as EDC37. Both EDC37 and PBX9501 are cyclotetramethylenetetranitramine-based (HMX-based) PBXs with high filler contents. The binder systems for the PBXs are very different: EDC37 consists of a nitroplasticized nitrocellulose and PBX9501 a nitroplasticized ESTANE. PBX9501 exhibits nearly invariant fracture strains of ?1.5?pct as a function of temperature at high strain rates, whereas EDC37 fails at ?2 to 2.5?pct. The maximum compressive strengths for both PBXs were measured at 150?Mpa at ?55??C, bu...
Mexico is located in a transition zone between the Nearctic and Neotropical biogeographical regions and contains a rich and unique biodiversity. A total of 496 Bacillus thuringiensis...Full Text Available
We compared the incidence of nasopharyngeal colonization by Streptococcus pneumoniae, the serotypes causing mucosal and invasive diseases, and the antibiotic resistance of these strains...Full Text Available
... view on the utility of such attacks, see JH Rothschild, Tomorrow's Weapons ... Aum Shinrikyo may have had a stolen vaccine anthrax strain incapable ...
In this study, bacterial strains were investigated in order to determine their heavy metal tolerance. The bacterial strains were identified as Bacillus cereus and Bacillus pumilus. In the batch system, the effects of operating variables such as solution pH, initial metal concentration, contact time, and adsorbent dosage were investigated. Both isolates were highly resistance to copper and lead in comparison with the control strain examined. The adsorption capacities of B. cereus and B. pumilus were found to be 22.1mg/g and 28.06mg/g, respectively. The biosorption follows pseudo-second order kinetics and the isotherm fits well to the Langmuir isotherm model. In column experiments, the biosorption was fitted well by the Thomas model. The breakthrough and exhaustion capacity of each biosorben...
The susceptibility of 19 isolates of Haemophilus ducreyi from a recent chancroid outbreak and four reference strains was determined in vitro to 13 antimicrobial agents. The rabbit intradermal...Full Text Available
Staphylococcus aureus isolates and 2 USA300 ATCC type strains for susceptibility to bacitracin and neomycin contained in over-the-counter antibacterial ointments. Resistance to...
... F ? (28.3)(108) in an isotherme.l deformation with stationary principal axes of strain rate, but the component might be as small as F2= (19-3)(100) ...
Eight culture-collection yeast strains of various species and five newly isolated stains were tested for both growth in olive oil extraction effluents and fermentation of the sugars in the same media. The culture-collection yeast strains did not grow in an effluent containing 2.86% sugar (w/v), 8 g/litre phenolic substances, 4.58 g/litre titratable acidity and pH 4.96, whereas the newly isolated strains of Torulopsis sp. MK-1, Saccharomyces norbensis MC-1, S. oleaceus MC-2 and S. oleaginosus grew well and fermented the sugars. In the medium mentioned above, they produced alcohol in amounts of 1.63 to 1.38%, respectively. None of the yeasts grew in an olive oil extraction effluent vacuum-concentrated to over 13-14% of dry matter. The strain of T. sp. MK-1 showed a higher stability.
The ability of a number of mycobacteria and some of their components to activate complement was examined. Mycobacterium bovis BCG (Glaxo strain), Mycobacterium leprae, Mycobacterium lepraemurium, and...Full Text Available
Activation energy values for high temperature deformation of a beta -titanium alloy Ti-10V were determined from the flow stress strain rate data taken from the second increasing strain rate cycles, in order to find the rate controlling mechanism. Although the data obtained from first increasing strain rate cycles are considered most appropriated by the author in a previous study due to obvious reasons, the values obtained in present work are again indicative of lattice self diffusion in beta -phase as the rate controlling mechanism for this alloy and nevertheless suggest that two different activation energy values for a deformation process could be possible in a given temperature range, depending upon the data. (author)
Retroelements constitute a large part of the human genome. These sequences are mostly silenced in normal cells, but genome-wide DNA hypomethylation in cancers might lead to their re-expression. Whether this re-expression really occurs in human cancers is largely unkown. We therefore investigated expression and DNA methylation of several classes of retroelements in human prostate cancer tissues and cell lines by quantitative reverse transcription-polymerase chain reaction and pyrosequencing, respectively. The most striking finding was strong and generalized increased expression of the HERV-K_22q11.23 provirus in cancers, including de novo expression of a spliced accessory Np9 transcript in some tumors. In parallel, DNA methylation in the long terminal repeat (LTR) decreased. Conversely, HER...
Phospholipase D (PLD) has been recognized as a regulator of cell proliferation and tumorigenesis, but little is known about the molecules regulating PLD expression. Thus, the identification of small molecules inhibiting PLD expression would be an important advance in PLD-mediated physiology. Quercetin, a ubiquitous bioactive flavonoid, is known to inhibit proliferation and induce apoptosis in a variety of cancer cells. In the present study, we examined the effect of quercetin on the expression of PLD in U87 glioma cells. Quercetin significantly suppressed the expression of PLD1 at the transcriptional level. Moreover, quercetin abolished the protein expression of PLD1 in a time and dose-dependent manner, as well as inhibited PLD activity. Quercetin suppressed NFkB-induced PLD1 expression vi...
The bifunctional wax ester synthase/acyl coenzyme A (acyl-CoA):diacylglycerol acyltransferase (WS/DGAT) from Acinetobacter sp. strain ADP1 (formerly Acinetobacter calcoaceticus...Full Text Available
A factor which agglutinated the spores of Ceratocystis fimbriata in the presence of Ca2+ was purified from sweet potato (Ipomea batatas Lam cv. Norin[1]) root. Element composition of the purified factor was as follows; analysis found: C (29.8%), H (3.97%), O (65.34%), N (0.81%): calculated for C43H69O70N1: C (30.02%), H (4.01%), O (65.15%), N (0.81%). The factor was mainly composed of galacturonic acid (53% of dry weight) and contained arabinose, fucose, and unidentified component as minor components. The factor also agglutinated A-, B-, AB-, and O types of human erythrocytes to almost the same degree in the presence of Ca2+. The differential spore-agglutinating activity of the factor depended on the pH of the assay medium; it agglutinated similarly the germinated spores of sweet potato and coffee strains at pH 7.5 and 5.5, whereas it displayed a distinct differential agglutinating activity at pH 6.5. The factor was assayed for spore-agglutinating activity at pH ...
Previously it was shown that the host-range gene of the Bratislava strain of avain sarcoma virus (B77 virus) spontaneously mutates with a very high rate. The wild-type B77 virus called B77 virus-II,...Full Text Available
The ERA strain of rabies virus was propagated in a baby hamster kidney cell line (BHK-21/C13). The viral titer was 10(1.8) tissue culture infective doses (TCID) higher than that of commercial ERA vaccine....Full Text Available
Time resolved phase transition and strain experiments have been performed on the millisecond time scale using a Bragg-edge transmission technique that has been developed at the Los Alamos National Laboratory. The precision with which lattice parameters can be determined from edge positions is sufficient to perform high-resolution strain measurements in uniaxial stress.
Time resolved phase transition and strain experiments have been performed on the millisecond time scale using a Bragg-edge transmission technique that has been developed at the Los Alamos National Laboratory. The precision with which lattice parameters can be determined from edge positions is sufficient to perform high-resolution strain measurements in uniaxial stress.
Vibrio cholerae 638 (El Tor, Ogawa), a new CTXΦ-negative hemagglutinin/protease-defective strain that is a cholera vaccine candidate, was examined for safety and immunogenicity...Full Text Available
The organization of lin genes and IS6100 was studied in three strains of Sphingomonas paucimobilis (B90A, Sp+, and UT26) which degraded hexachlorocyclohexane...Full Text Available
The capacity of bones to adjust their mass and architecture to withstand the loads of everyday activity derives from the ability of their resident cells to respond appropriately to the strains engendered....Full Text Available
Understanding the mechanical properties of biomedical devices is critical in predicting and preventing their failure in the body. Such knowledge is essential, for example, in the design of biomedical stents, which must undergo repeated strain over their ten year lifetimes without breaking. Computational models are used to predict mechanical response of a device, but these models are not complete; there are significant deviations from the predictions, especially when devices are subjected to repeated multi-axial loads. Improving these models requires comparisons with actual measurements of strained nitinol. Local measurements of the full strain tensor can be made using X-ray diffraction techniques, but they are currently limited to materials whose grain size is larger than the X-ray beam size or require several diffraction patterns produced by rotation of the sample. Nitinol stents are nanocrystalline, with grains smaller ...
Ditercalinium, an antitumor bifunctional intercalator which forms a high affinity reversible complex with DNA, was found to be specifically cytotoxic for polA and lig7 E. coli strains. In the polA strain,...Full Text Available
In order to investigate the extrusion characteristics of magnesium alloy (AZ31), a computer simulation was attempted. Tensile properties of as-cast billet with different strain rates were incorporated into the simulation. The results showed a great change in distribution of stress and strain at near die region by the ram travel. It was found that the average grain size at longitudinal edge of the extruded sheet was smaller than that at center region, which might be attributed to recrystallization caused by severe plastic deformation. (orig.)
A nationwide surveillance for antimicrobial susceptibility in Escherichia coli strains isolated from food-producing animals in Japan was conducted from 1999 to 2002. Eighteen cefazolin-resistant...Full Text Available
Fifteen strains of CDC group 1 coryneform and biochemically similar bacteria were isolated from clinical specimens. Of the 15 strains isolated, 11 were derived from abscesses and purulent lesions, mostly...Full Text Available
Earlier we have shown that exogenous expression of HIPPI, a molecular partner of Huntingtin interacting protein HIP-1, induces apoptosis and increases expression of caspases-1, -8 and -10 in HeLa and...Full Text Available
BackgroundHigh complexity is considered a hallmark of living systems. Here we investigate the complexity of temporal gene expression patterns using the concept of Permutation Entropy...Full Text Available
Many of the gene products that participate in nitrogen metabolism are sensitive to nitrogen catabolite repression (NCR), i.e., their expression is decreased to low levels when readily used nitrogen...Full Text Available
BackgroundPeroxiredoxins (Prxs) have recently been suggested to have a role in tumorigenesis.MethodsWe studied the expression of Prx I-VI and their...Full Text Available
In rats, expression of the immediate early gene, c-fos observed in the brain following male copulatory behavior relates mostly to the detection of olfactory information originating...Full Text Available
Although genetically identical for autosomal Chrs (Chr), male and female preimplantation embryos could display sex-specific transcriptional regulation. To illustrate sex-specific differences at the...Full Text Available
alpha-actinins are actin microfilament crosslinking proteins. Vertebrate actinins fall into two classes: the broadly-expressed actinins 1 and 4 (actn1 and actn4)...Full Text Available
PurposeIn our previous studies we showed that upregulating claudin-6 (CLDN6) expression may contribute to preventing breast cancer, and that 17β-estradiol induces a concentration-...Full Text Available
Previous studies have been conducted in gene expression profiling to identify groups of genes that characterize the colorectal carcinoma disease. Despite the success of previous attempts to identify...Full Text Available
PurposeNocturnal rhythms of gene expression in the retina are known to be both darkness- and circadian clock-dependent, but their role and cellular location are not well defined....Full Text Available
Sensory neurons in aging mammals undergo changes in anatomy, physiology and gene expression that correlate with reduced sensory perception. In this study we compared young and aged mice to identify...Full Text Available
Gene expression is a unique way of characterizing how cells and organisms adapt to changes in the external environment. The measurements of gene expression levels upon exposure to a chemical can be...Full Text Available
Increased intrauterine prostaglandin (PG) production is crucial for the initiation of parturition. To investigate the mechanisms controlling intrauterine PG synthesis, we examined the expression of...Full Text Available
AIM: To investigate the role of metallothionein in colorectal tumours and the possible relation with other factors associated with tumour progression: expression of cathepsin D (CD), CD44, p53, Rb,...Full Text Available
Expressed emotion measures, encompassing dimensions of criticism (CRIT), and emotional overinvolvement (EOI) are increasingly being used to assess the parent–child relationship in child...Full Text Available
We have used Western blot analysis and immunocytochemistry to determine the effect of dietary K intake on the expression of protein kinase C (PKC) isoforms in the kidney. Western blot has demonstrated...Full Text Available
The ability to achieve tumor selective expression of therapeutic genes is an area that needs improvement for cancer gene therapy to be successful. One approach to address this is through the...Full Text Available
OBJECTIVE—Identification of arterial genes and pathways altered in obesity and diabetes.RESEARCH DESIGN AND METHODS—Aortic gene expression profiles of...Full Text Available
Male transgenic mice expressing the polyomavirus middle T (PyV-MT) gene exhibited growth and developmental abnormalities in prostatic and other urogenital epithelium. Expression of PyV-MT was directed...Full Text Available
Endothelial cells and mural cells (smooth muscle cells, pericytes, or fibroblasts) are known to communicate with one another. Their interactions not only serve to support fully functional blood...Full Text Available
AimsThe aims of the study were to study the effect of pre-operative treatment on the expression of tumour-related proteins and to correlate the expression of these...Full Text Available
The ToxRS system in Vibrio cholerae plays a central role in the modulation of virulence gene expression in response to environmental stimuli. An integration of multiple signalling inputs...Full Text Available
AbstractIntrathymic expression of tissue-restricted antigens (TRAs) has been viewed as the key element in the induction of central tolerance and recently, a central role for the autoimmune...Full Text Available
BackgroundCD26 (dipeptidyl peptidase IV, DPPIV) is a 110 kDa surface glycoprotein expressed in most normal tissues, and is a potential novel therapeutic target for selected cancers....Full Text Available
BackgroundGene expression profiling and the analysis of protein-protein interaction (PPI) networks may support the identification of disease bio-markers and potential drug targets....Full Text Available
Hormone potency depends on receptor availability, regulated via gene expression and receptor trafficking. To ascertain how central leptin receptors are regulated, the effects of leptin challenge, high-fat...Full Text Available
The aim of the present study was to identify specific behavioral patterns that contribute to diminished estrus expression in lame cows. Behavioral scan and focal sampling were used to examine...Full Text Available
BackgroundRecent data show aberrant and altered expression of regulatory noncoding micro (mi) RNAs in prostate cancer (PCa). A large number of miRNAs are encoded in organized intronic...Full Text Available
Exploring the possibility of enhancing the properties of baculoviruses as biological control agents of insect pests, we tested the effect of expressing an insect gene (jhe) encoding juvenile hormone...Full Text Available
BackgroundThe immunoregulatory enzyme indoleamine 2,3-dioxygenase, which catalyzes the conversion of tryptophan into kynurenine, is expressed in a significant subset of patients...Full Text Available
To gain insight into ATP-binding cassette transporter A1 (ABCA1) function and its potential role in AD pathology, we analyzed the expression of the cholesterol transporter ABCA1...Full Text Available
IntroductionPrevious observations suggest that active systemic juvenile idiopathic arthritis (sJIA) is associated with a prominent erythropoiesis gene-expression signature. The aim...Full Text Available
BackgroundASCL1 role in pancreatic endocrine tumourigenesis has not been established. Recently it was suggested that ASCL1 negatively controls expression of the...Full Text Available
BackgroundThe hard clam, Mercenaria mercenaria, has been affected by severe mortality episodes associated with the protistan parasite QPX (Quahog Parasite Unknown)...Full Text Available
Optimal sample handling techniques for tissue preparation and storage, RNA extraction and quantification, and target gene detection are crucial for reliable gene expression analysis. Methods...Full Text Available
Two heterologous expression systems using thioredoxin (trxA) as a gene fusion part in Escherichia coli were developed to produce recombinant pediocin PA-1. Pediocin...Full Text Available
The availability of full genome sequences has allowed the construction of microarrays, with which screening of the full genome for changes in gene expression is possible. This method can provide a wealth...Full Text Available
The results of a study of the expression of embryonic hemoglobin genes in mice which show an imbalance of alpha and non-alpha chain synthesis are reported. (ACR)
Human endometrium resists embryo implantation except during the 'window of receptivity'. A change in endometrial gene expression is required for the development of receptivity. Uterine calbindin-D28k...Full Text Available
Infection with the Ad5-SVR4 virus was used to introduce the large T antigen encoding region of the SV40 virus into bovine and human corneal endothelial cells. Expression of large T antigen occurred...Full Text Available
To study the expression of Fc receptors in human alveolar macrophages (AM), the cells were collected from 12 healthy controls and 22 patients with sarcoidosis and the activity involved in binding to...Full Text Available
PknB is a member of the newly discovered eukaryotic-like protein serine/threonine kinase (PSTK) family of proteins. The pknB gene was cloned and expressed in Escherichia coli....Full Text Available
Zygotes of fucoid algae have long been studied as a paradigm for cell polarity. Polarity is established early in the first cell cycle and is then expressed as localized growth and invariant cell division....Full Text Available
Phox2b-expressing neurons of the retrotrapezoid nucleus (RTN) located in the ventrolateral brainstem are sensitive to changes in PCO2/pH, have excitatory projections...Full Text Available
We developed mice with germline endogenous expression of oncogenic Hras to study effects on development and mechanisms of tumor initiation. They had high perinatal mortality, abnormal...Full Text Available
Pseudomonas mandelii liquid cultures were studied to determine the effect of pH and temperature on denitrification gene expression, which was quantified by quantitative reverse transcription-PCR....Full Text Available
Normal mouse epidermis constitutively expresses prostaglandin-H synthase 1 (PGHS-1) but no PGHS-2. Acute inflammation and epidermal hyperplasia, (hyperplastic transformation), as evoked in adult mouse...Full Text Available
BackgroundThough long known to affect smooth muscle biology, recent studies indicate that phosphodiesterase 5 (PDE5) is also expressed in myocardium. Recognizing that the regulation...Full Text Available
Systemic administration of lipopolysaccharide (LPS), which causes endotoxemia and systemic inflammation, has been reported to induce expression of the gene for type II inducible nitric oxide synthase...Full Text Available
BackgroundThe aim of the study was to develop a virtual microscopy enabled method for assessment of Ki-67 expression and to study the prognostic value of the automated analysis in...Full Text Available
Lymphocytes from patients with insulin-dependent diabetes mellitus (IDDM), a chronic autoimmune disease, have recently been shown to have decreased surface expression of MHC class I antigens. Since...Full Text Available
SummaryHuman skin expresses elements of the hypothalamo-pituitary-adrenal (HPA) axis including pro-opiomelanocortin (POMC), corticotropin releasing hormone (CRH), the CRH receptor-1...Full Text Available
Histone Arg methylation and Lys acetylation have been found to cooperatively regulate the expression of p53 target genes. Peptidylarginine deiminase 4 (PAD4) is an enzyme that citrullinates...Full Text Available
The cDNA encoding the B chain of the plant toxin ricin has been cloned and expressed in monkey kidney COS-M6 cells. The recombinant B chain was detected by labeling the transfected cells with [35S]methionine...Full Text Available
AIM: To investigate the relation of Fas and Fas ligand (FasL) protein expression with carcinogenesis and metastasis of gastric carcinoma.METHODS: Immunohistochemistry was used to detect Fas and...Full Text Available
Astrocytes have long been perceived only as structural and supporting cells within the central nervous system (CNS). However, the discovery that these glial cells may potentially express receptors capable...Full Text Available
The human CYP3A subfamily is of interest due to its multiplicity, activity toward known carcinogens, and extrahepatic expression. In situ hybridisation analysis of formalin fixed, routinely processed...Full Text Available
Recombinant biotin-binding phages were affinity-selected from a random peptide library expressed on the surface of filamentous phage. Phage binding to biotinylated proteins was half-maximally inhibited...Full Text Available
Antisense radiopharmaceuticals could be used to image gene expression in the brain in vivo, should these polar molecules be made transportable through the blood–brain barrier....Full Text Available
Rapid development in genomics in recent years has allowed the simultaneous measurement of the expression levels of thousands of genes using DNA microarrays. This has offered tremendous potential...Full Text Available
BackgroundGATA-2 is a transcription factor required for hematopoietic stem cell survival as well as for neuronal development in vertebrates. It has been shown that specific expression...Full Text Available
Gene expression profiling has played an important role in cancer risk classification and has shown promising results. Since gene expression profiling often involves determination of a set of...Full Text Available
Uniaxial low-cycle fatigue and creep-fatigue tests have been carried out on hollow alloy 800 specimens that were filled with steam. Two testing temperatures were employed, each with its own steam condition. These temperatures and steam conditions were 650/sup 0/F with saturated steam (5% liquid, 95% vapor) and 1200/sup 0/F with superheated steam at 2200 psi. The low-cycle fatigue tests were carried out at both 650/sup 0/F and 1200/sup 0/F by cycling the strain between equal tensile and compressive magnitudes until specimen failure or until it was no longer practical to continue the test. The creep-fatigue tests were carried out to failure by cycling the strain in the same fashion as in the low-cycle fatigue tests but with holds imposed at either the peak tensile strain or the peak compressive strain or at both peak tensile and compressive strains in each loading cycle.
Metastable austenitic steels show excellent mechanical properties, such as high strength combined with excellent ductility and toughness due to martensitic transformation under mechanical loading (transformation induced plasticity effect). A good energy consumption, and, in the case of high-alloyed metastable austenitic steels, a high corrosion resistance, increase the potential of these materials for diverse applications, also in regard of safety requirements. Up to now, numerous wrought alloys were investigated concerning mechanical behaviour, TRIP-effect, martensitic transformation behaviour and modelling of transformation kinetics or stress-strain behaviour. New high alloyed cast CrMnNi-steels, developed at Technical University Bergakademie Freiberg, provide the chance to reduce processing steps, production time and costs. In order to understand the influence of temperature on the martensitic phase transformation behaviour and therefore on mechanical properties ...
Electron spin polarization in excess of 70% has been observed in photoemission from a 0.1 #mu#m-thick epitaxial layer of In_xGa_1_-_xAs with x #approx# 0.13 grown on a GaAs substrate. Under these conditions, the epitaxial layer is expected to be highly strained by the 0.9% lattice mismatch, as confirmed by x-ray diffractometer measurements of the lattice parameter. The electron polarization and the quantum efficiency have been measured as a function of the excitation photon energy from 1.25 to 2.0 eV. A significant enhancement of the electron polarization occurs in the vicinity of 1.33 eV where the expected strain-induced level splitting permits optical excitation of a single band transition. Measurements made on a control sample of 1.14 #mu#m thickness, significantly larger than the critical thickness for pseudomorphic strain, show no polarization enhancement. These measurements represent the first observation of ...
The strain dependence of Si-Ge interdiffusion in epitaxial Si/Si{sub 1-y}Ge{sub y}/Si heterostructures on relaxed Si{sub 1-x}Ge{sub x} substrates has been studied using secondary ion mass spectrometry, Raman spectroscopy, and simulations. At 800 and 880 deg. C, significantly enhanced Si-Ge interdiffusion is observed in Si/Si{sub 1-y}Ge{sub y}/Si heterostructures (y=0.56, 0.45, and 0.3) with Si{sub 1-y}Ge{sub y} layers under compressive strain of -1%, compared to those under no strain. In contrast, tensile strain of 1% in Si{sub 0.70}Ge{sub 0.30} layer has no observable effect on interdiffusion in Si/Si{sub 0.70}Ge{sub 0.30}/Si heterostructures. These results are relevant to the device and process design of high mobility dual channel and heterostructure-on-insulator metal oxide semiconductor field effect transistors.
Material testing of SPF-sheet is usually done with coupon hot tensile testing. The optimum range of strain rates is determined with stepped strain tests. To overcome the problem of very few available testing facilities and time consuming and costly procedure, cone cup testing has been developed since long. This test can be generated directly in the workshop, no machining of samples is necessary and it is very much related to the real SPF-process. The analysis of suitable temperature and strain rate is done by simple measurement of resulting cone height. This paper describes a unique and novel variant of the above mentioned baseline design. It provides on-line data of the actual status of the cone cup forming resulting from the applied, constant pressure. Strain rate variations as a result from texture or from the alloy-related behaviour is detectable. Thinning and ...
An internal-tin-process Nb{sub 3}Sn conductor, which is a prototype for the International Thermonuclear Experimental Reactor (ITER), was tested. The axial strain measurements were made over a range of magnetic fields from 15 to 25 T. The conductor specifications are given in Table 5, and the measured data are presented in Table 6 and Figs. 8 through 10. The I{sub c} and J{sub c} values are based on an electric field criterion (E{sub c}) of 2 {mu}V/cm. The results show a zero-strain 15 T value of J{sub c} (referred to the noncopper area) which was 0.50 GA/m{sup 2} and a peak (strain-free) J{sub c} value of 0.55 GA/m{sup 2}. The irreversible strain limit was reasonably high, 0.92%, and the compressive prestrain was 0.28%. The sample did not fracture until 1.09% strain.
Microstructural evolution due to thermal effects was studied in micro solder joints (55 {+-} 5 {micro}m). The composition of the Sn/Pb solder studied was found to be hypereutectic with a tin content of 65--70 wt%.This was determined by Energy Dispersive X-ray analysis and confirmed with quantitative stereology. The quantitative stereological value of the surface-to-volume ratio was used to characterize and compare the coarsening during thermal cycling from 0--160 C to the coarsening during annealing at 160 C. The initial coarsening of the annealed samples was more rapid than the cycled samples, but tapered off as time to the one-half as expected. Because the substrates to which the solder was bonded have different thermal expansion coefficients, the cycled samples experienced a mechanical strain with thermal cycling. The low-strain cycled samples had a 2.8% strain imposed on the solder and failed by 1,000 cycles, despite ...
The paper examines the influence of various total strain amplitudes and mean strains on the cyclic deformation processes in GGG-60 at temperatures of 20 C, 350 C, and 500 C ,the total strain amplitudes being varied between 1.0 permille {<=}{epsilon}{sub a,t}{<=}3.8 permille , and the mean strains between -4.0 permille {<=}{epsilon}{sub m,t}{<=}4.0 permille . - [Deutsch] In der Arbeit wird der Einfluss unterschiedlicher Totaldehnungsamplituden und Mitteldehnungen auf das Wechselverformungsverhalten von GGG-60 bei Temperaturen von 20 C, 350 C und 500 C untersucht. Dabei werden die Totaldehnungsamplituden zwischen 1,0 permille {<=} {epsilon}{sub a,t} {<=} 3,8 permille und die Mitteldehnungen zwischen -4,0 permille {<=} {epsilon}{sub m,t} {<=} 4,0 permille variiert. (orig./MM)
Fingerprinting of Penicillium crustosum strains was performed using different phenotypic characteristics. Seven strains of this extremely homogenous species were selected; of these, five originated from geographical locations characterized by low temperatures, and one from a location with a low water activity. Principal component analysis (PCA) was performed using micromorphological data, temperature- and water-dependent growth rates, and extrolite profiles obtained by HPLC analysis. The micromorphological data were less informative, while the growth-rate data were informative only if the strains investigated already showed slight adaptations to the selected external parameter. In contrast, PCA analyses of the extrolite data showed groupings of the strains according to their origins and known physiological differences. These groupings are in full agreement with the clustering obtained by previous ...
Water and mud samples were collected from canals and rivers which were adjacent to outlets discharging warm water of 3 power plants in Berlin. Downstream samples from 1 bathing resort were also collected. Free living amoebae were isolated from 138 water and 69 mud samples. From these respectively 156 and 73 strains could be cultured and were administered intranasally to mice for pathogenicity tests. Two Acanthamoeba strains from water and 7 from mud could be reisolated from mouse brain and or lungs, although no pathological disorders could be observed. Five Naegleria strains were negative in mouse inoculation tests. Four Acanthamoeba strains which were positive in mice were cultured at + 45 degrees C; no cytopathogenic effects were observed in tissue cultures. Acanthamoeba infective for mice could also be isolated from samples at low water temperatures. Further investigations have to show, whether ...
Escherichia coli B and K-12 are equally susceptible to the bacteriostatic effects of aerobic paraquat, but they differed strikingly when the lethality of paraquat was evaluated. E. coli B suffered an apparent loss of viability when briefly exposed to paraquat, whereas E. coli K-12 did not. This difference depended on the ability of the B-strain, but not the K-12 strain, to retain internalized paraquat; the B strain was killed on aerobic tryptic soy-yeast extract plates during the incubation which preceded the counting of colonies. This difference in retention of paraquat between strains was demonstrated by delayed loss of viability, by growth inhibition, and by cyanide-resistant respiration after brief exposure to paraquat, washing, and testing in fresh medium. This difference was also shown by using ({sup 14}C)paraquat. This previously unrecognized difference between E. coli B and K-12 has been the ...
The mechanical behaviour of wrought magnesium alloy AZ31 has been characterised by tensile testing at room temperature. Tests were carried out at various strain rates between 0.00003 s{sup -1} and 0.01 s{sup -1} on material which had been extruded to a bar of approximately 6 mm thick, and 80 mm wide. Specimens were machined from three orientations relative to the extrusion direction: parallel, perpendicular, and 45 from the extrusion direction. Significant variations of the properties were observed depending on the extrusion orientation and strain rate. At all strain rates the yield stress declined as the test orientation was rotated away from the extrusion direction. Parallel to the extrusion direction, the yield stress was found to increases markedly with increasing strain rate, whereas at 45 and 90 a lesser influence of strain rate was observed. The work hardening exponent was ...
We demonstrate that expression of the UGA1, CAN1, GAP1, PUT1, PUT2, PUT4, and DAL4 genes is sensitive to nitrogen catabolite repression. The expression of all these genes, with the exception of UGA1...Full Text Available
Here, we provide the first study of prolactin (PRL) and prolactin receptor (PRLR) expression during the nonseasonal murine hair cycle, which is, in contrast to sheep, comparable with the human scalp...Full Text Available
We have developed a new expression vector, pcIts ind+, based upon the powerful rightward promoter of bacteriophage lambda, which is controlled by a temperature-sensitive...Full Text Available
Purpose The paired-like homeodomain transcription factor 2 (PITX2) gene encodes a transcription factor controlled by the WNT/Dvl/CTNNB1 and Hedgehog/TGFB pathways in the pathogenesis of colorectal cancer (CRC). Although PITX2 is reportedly involved in various functions, including tissue development by controlling cell growth, its significance in CRC remains unclear. We report our findings regarding abnormal PITX2 expression in human CRC. Methods PITX2 expression was evaluated in 5 human CRC cell lines and 92 primary CRC samples. Cell growth was evaluated after inhibition of PITX2 expression or after exogenous introduction of PITX2. Results PITX2 expression was seen in all the five CRC cell lines. The study of tissue samples indicated that PITX2 expression was significantly higher in cancer...
We studied the strain introduced in a Si(111) substrate due to MeV ion implantation using extremely asymmetric x-ray diffraction and measured the rocking curves of asymmetrical 113 diffraction for the Si substrates implanted with a 1.5 MeV Au"2"+ ion at fluence values of 1x10"1"3, 5x10"1"3, and 1x10"1"4/cm"2. The measured curves consisted of a bulk peak and accompanying subpeak with an interference fringe. The positional relationship of the bulk peak to the subpeak and the intensity variation of those peaks with respect to the wavelengths of the x rays indicated that crystal lattices near the surface were strained; the lattice spacing of surface normal (111) planes near the surface was larger than that of the bulk. Detailed strain profiles along the depth direction were successfully estimated using a curve-fitting method based on Darwin's dynamical diffraction theory. Comparing the shapes of resultant ...
Abstract Purpose: To describe the pattern of expression of the cyclin-dependent kinase inhibitors (CDKIs) p16, p21 and p27, and the cell cycle in SRA 01/04 cells relative to contact inhibition. Methods: SRA 01/04 cells were grown to overconfluence under normal conditions. At various phases of the cell growth, cells were assayed by flow cytometry and Western blotting for the expression of CDKIs. Results: Expression of p16 was detected from early logarithmic growth to stationary phases, during which the number of cells in G0/G1 increased from 46 to 69%. Expression of p21 was detected only during the overgrowth phase, when 60% of the cells were in G0/G1. Expression of p27 was not observed in SRA 01/04 cells. Conclusions: p16 expression was likely mediated by G0/G1 arrest to induce contact inh...
The type III secretion system among Gram-negative bacteria is known to deliver effectors into host cell to interfere with host cellular processes. The type III secretion system in Yersina, Pseudomonas and Enterohemorrhagic Escherichia coli have been well documented to be involved in the bacterial pathogenicity. The existence of type III secretion system has been demonstrated in neuropathogenic E. coli K1 strains. Here, it is observed that the deletion mutant of type III secretion system in E. coli strain EC10 exhibited defects in the invasion and intracellular survival in Acanthamoeba castellanii (a keratitis isolate) compared to its parent strain. Next, it was determined whether type III secretion system plays a role in E. coli K1 survival inside Acanthamoeba during the encystment process...
Material test results are presented for the mechanical behavior of Nylon 66 in compression. Static compression modes include direct compression, stress relaxation and creep. Dynamic direct compression results are included. Tests are performed at atmospheric pressure; strain rates range from 10/sup /minus/4/sec to 10/sup 2/sec; temperatures are 20, 65, 110, 150 and 200/degree/C; moisture levels are 0% (dry), 2% and 6% (saturated); true strains to /minus/0.25 are imposed. Our empirical Temperature-Moisture equivalence of 14/degree/C per 1% moisture is discussed with respect to the /open quotes/free volume/close quotes/ concept.
There have been many stress measurements on welds by neutron diffraction over the past 20 years but there are still a number of serious experimental issues that are often not addressed. The primary fact is that the microstructure generally changes across the weld and accompanying this may be a change in the concentration of strengthening elements in solution. This will lead to a shift in lattice spacing which may be incorrectly interpreted as a strain. Secondly, a gradient of plastic deformation near the weld may be expected. Since plastic deformation by application of a stress always generates intergranular (type-2) strains this may lead to a range of intergranular effects superposed on the conventional weld-related strains. The effects are illustrated by neutron diffraction studies of Zr-4, ferritic and austenitic welds where chemistry, intergranular effects and crystallographic texture can all play a role.
Humic acids are considered problematically in drinking water because it can react readily with chlorine to form carcinogen compounds and its biological removal is much recommended. The scanning electron microscopy morphologies and optical parameters observed for natural humic acids (NHAs) extracted from different soils at Mitidja plain (Algeria) made them different from the commercial ones. Three of the most active strains of 19 actinomycetes were isolated and selected from surface soils at this plain. These strains were identified based on cultural characteristics and chemotaxonomic analysis and classified in the genus Streptomyces. Growth of these strains was assured on a poor liquid medium containing NHAs as carbon and nitrogen sources and degradation occur only in the presence of gluco...
The authors have shown that toxicity of paraquat for Escherichia coli is increased over 1-fold in strains defective in the biosynthesis of spermidine compared to isogenic strains containing spermidine. The increased sensitivity of these spermidine-deficient mutants to paraquat is eliminated by growth in medium containing spermidine or by endogenous supplementation of spermidine by the use of a speE"+D"+ plasmid. No paraquat toxicity is seen in the absence of oxygen, even in amine-deficient strains, indicating that superoxide is the agent responsible for the increased toxicity. However, the specific mechanisms responsible for the increased paraquat toxicity in the spermidine-deficient mutants remain to be determined. The marked sensitivity to paraquat of E. coli deficient in spermidine is of particular interest, since such mutants have no other phenotypic properties that can be easily assayed. This increased sensitivity has ...
Electron-spin polarization in excess of 70% has been observed in photoemission from a 0.1-#mu#m-thick epitaxial layer of In_xGa_1_-_xAs with x#approx#0.13 grown on a GaAs substrate. Under these conditions, the epitaxial layer is expected to be highly strained by the 0.9% lattice mismatch. The electron polarization and the quantum efficiency have been measured as a function of the excitation photon energy from 1.25 to 2.0 eV. A significant enhancement of the electron polarization occurs in the vicinity of 1.33 eV where the expected strain-induced level splitting permits optical excitation of a single-band transition.
The growth of thin Pd[sub 2]Si films on Si(111) surfaces is studied using [ital in] [ital situ] transmission electron microscope under ultrahigh vacuum conditions. No immediate reaction of deposited Pd with Si is observed at room temperature. At [similar to]200 [degree]C, uniform Pd[sub 2]Si films can be formed. The thin Pd[sub 2]Si films are found to grow into strained islands at elevated temperatures. Interfacial misfit dislocations associated with interfacial steps propagate across the strained islands, causing the islands to grow layer-by-layer at the interface. The strain fields associated with the misfit dislocations are believed to be responsible for this behavior.
This paper describes a nonlinear dynamic analysis of TVA high energy line pipe whip tests using the ABAQUS-EPGEN code. The analysis considers the effects of large deformation and strain rate on resisting moment and energy absorption capability. The numerical results of impact forces, impact velocities, pipe strains, and reaction forces at pipe supports are compared to the TVA test data. The calculated pipe whip impact time and forces are also compared with those predicted using current industry practice. The calculated pipe support reaction forces are found to be in good agreement with the TVA test data except for some peak values at the very beginning of the pipe break. These peaks are believed to be due to stress wave propagation which cannot be addressed by the ABAQUS code. Both elbow crushing and strain rate have been approximately simulated. The effects are found to be important for pipe whip impact evaluation.
Abstract Host-microorganism interactions in the intestinal tract are complex, and little is known about specific nonpathogenic microbial factors triggering host responses in the gut. In this study, mannose-specific interactions of Lactobacillus plantarum 299v with jejunal epithelium were investigated using an in situ pig Small Intestinal Segment Perfusion model. The effects of L. plantarum 299v wild-type strain were compared with those of two corresponding mutant strains either lacking the gene encoding for the mannose-specific adhesin (msa) or sortase (srtA; responsible for anchoring of cell surface proteins like Msa to the cell wall). A slight enrichment of the wild-type strain associated with the intestinal surface could be observed after 8 h of perfusion when a mixture of wild-type and...
Silicon layered structures containing porous silicon modified with various thermal treatments and epitaxial layers deposited on porous layers were studied with a number of complementary X-ray diffraction methods using synchrotron source. The methods of characterization included recording of rocking curves for reflections with various asymmetry as well as projection, section and micro-Laue topography. It was found that oxidizing and sintering of porous silicon seriously modified the strains in the porous layer and in some cases even inverting the sense of strain with respect to that in initially formed porous layer. Consequently the deposited epitaxial layer usually was not laterally coherent with the substrate. Some of investigated layers were not stable in time and after few months period exhibited significant lost of coherence of porous skeleton. (author)
The development of a twinned microstructure in hexagonal close-packed rolled magnesium compressed in the in-plane direction has been monitored in situ with neutron diffraction. The continuous conversion of the parent to daughter microstructure is tracked through the variation of diffraction peak intensities corresponding to each. Approximately 80% of the parent microstructure twins by 8% compression. Elastic lattice strain measurements indicate that the stress in the newly formed twins (daughters) is relaxed relative to the stress field in the surrounding matrix. However, since the daughters are in a plastically 'hard' deformation orientation, they quickly accumulate elastic strain as surrounding grains deform plastically. Polycrystal modeling of the deformation process provides insight about the crystallographic deformation mechanism involved.
A new test methodology is described which allows access to loading rates that lie between split Hopkinson bar and shock-loading techniques. Gas gun experiments combined with velocity interferometry techniques have been used to experimentally determine the intermediate strain-rate loading behavior of Coors AD995 alumina and Cercom silicon-carbide rods. Graded-density materials have been used as impactors; thereby eliminating the tension states generated by the radial stress components during the loading phase. Results of these experiments demonstrate that the time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod. This allows access to intermediate loading rates over 5 x 10{sup 3}/s to a few times 10{sup 4}/s.
Dynamic development of new grain boundaries was studied in compression of a magnesium alloy AZ31 with initial grain sizes (D{sub 0}) of 22 {mu}m and 90 {mu}m at a temperature of 673 K. Kink bands are evolved near corrugated grain boundaries and in grain interiors at low strains accompanied with new fine grains. Kink bands are developed often perpendicular to the basal plane. The boundary misorientation of kink band as well as the volume fraction of new grains increases rapidly with increasing strain and approaches a saturation value in high strain. New fine grains are developed faster with decrease in the D{sub 0}. It is concluded that new grain evolution is controlled by a deformation-induced continuous reaction, i.e. continuous dynamic recrystallization (DRX). (orig.)
High temperature deformation behavior of an alpha + beta titanium alloy Ti-3Al-2.5V has been investigated in the temperature range 830 deg. C to 910 deg. C by using the method of cross head speed cycling. On the basis of flow stress-strain rate and strain rate sensitivity data, it was found that the alloy exhibits a hardening effect in the entire temperature range studied, amount of hardening being significant at the highest test temperature of 910 deg. C which resulted in a degradation of superplastic properties of the alloy. Grain growth in beta-phase due to strain was considered responsible for the hardening effect observed.
Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the polymorphs'' of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes worm holes'' in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100[degrees]C lock in the mechanical twins.
Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the ``polymorphs`` of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes ``worm holes`` in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100{degrees}C lock in the mechanical twins.
The function of selenium in an organism is mediated mostly by selenoproteins including glutathione peroxidase. Glutathione peroxidase is a potent anti-oxidative enzyme, scavenging a variety of peroxides. The green alga Scenedesmus quadricauda was used to investigate the relationship between the toxicity of selenium and the glutathione peroxidase activity. Selenium resistant strains SeIV and SeVI were synchronized and grown in high concentrations of Se (selenite or selenate). As a measure of selenium toxicity the EC50 values were determined. During growth of the untreated wild type, glutathione peroxidase activity increased slightly and then declined gradually until the end of the cell cycle. A similar pattern was observed in untreated resistant strains and when resistant strains were grown...
Prepulse inhibition (PPI) is a measure of sensorimotor gating, a pre-attentional inhibitory brain mechanism that filters extraneous stimuli. Prepulse inhibition is correlated with measures of cognition and executive functioning, and is considered an endophenotype of schizophrenia and other psychiatric illnesses in which patients show PPI impairments. As a first step toward identifying genes that regulate PPI, we performed a quantitative trait locus (QTL) screen of PPI phenotypes in a panel of mouse chromosome substitution strains (CSSs). We identified five CSSs with altered PPI compared with the host C57BL/6J strain: CSS-4 exhibited decreased PPI, whereas CSS-10, -11, -16 and -Y exhibited higher PPI compared with C57BL/6J. These data indicate that A/J chromosomes 4, 10, 11, 16 and Y harbor...
This paper presents experimental and analytical results of pipe whip tests performed under PWR LOCA conditions using a test pipe of 4-inch diameter and U-shaped restraints. In the tests, the effects of the overhang length on the pipe whip behavior of the piperestraints system were studied by measuring the strains and deformations of the test pipe and restraints, and the restraints forces. The equation for predicting the maximum strain at the outer surface of the pipe was derived using a static equilibrium condition. The calculated maximum strains at the outer surface of the pipe agree fairly well with experimental data. The dynamic response analysis of the pipe-restraints system was conducted by the finite element program ADINA. The applicability of the ADINA program to the pipe whip analysis is made clear through this analysis.
The evolution of intergranular lattice strains in a textured, forged bar (Bar) sample of the #alpha# - #beta# titanium alloy Ti-6Al-4V has been characterised using in situ X-ray diffraction. A two-phase elastic-plastic self-consistent (EPSC) model has been developed to rationalise the results. Of the orientations analysed, it is found that the #left brace#2 0 0#right brace# #beta# orientation is the most compliant and that load partitions to this orientation during plasticity. The results from the bar material have then been used to predict the response of unidirectionally rolled plate (UD) Ti-6Al-4V. It is predicted that the residual lattice strains in the #left brace#101-bar0#right brace# and #left brace#112-bar0#right brace# orientations will be significantly higher in the UD material.
Genes for chloramphenicol resistance, Cm(r) and tetracycline resistance, Tc(r), which are present as heterologous insertions in the chromosomes of some clinical isolates of Streptococcus pneumoniae (pneumococcus) and derivative strains, were transferred at a low frequency to other pneumococci by a DNase-resistant filter mating process that resembles conjugation. Cotransfer of Cm(r) and Tc(r) was the most common event. Neither the donor strains nor the transconjugants contained detectable plasmids. Transconjugants acted as donors for transformation and for filter mating and had properties similar to those of the parent strain. The presence of the conjugative plasmid pIP501 in the donor did not appear to influence the transfer properties of the Cm(r) or Tc(r) determinants.
In this study, experiments were performed for pipe whip phenomena simulation. The analytical method was developed by combining several kinds of elements in ABAQUS computer code, standard version 5.2 . The transient analytical and the experimental results of the pipe whip test using 6 inch diameter pipe and U-shaped restraints are presented. It is shown that the adequate clearance decreases the restraint strains. As the overhang length increased, the maximum strain of restraints decreased. When the impact force increased, the maximum restraint strain increased slightly. The analytical models simulate the experimental impact phenomena very precisely, with slight conservatism. It is verified that the analytical method developed is very suitable to pipe whip phenomena analysis in nuclear power plants. 6 refs., 10 figs., 1 tab.
Pathogenic strains of Vibrio cholerae are lysogens of the filamentous phage CTXφ, which carries the genes for cholera toxin (ctxAB). We found that the titers...Full Text Available
Genetic studies of nicotine addiction in mice have utilized the oral self-administration model. However, it is unclear if strain differences in nicotine consumption are influenced by variation in bitter...Full Text Available
Strain F, a recently isolated ruminal bacterium, grew rapidly with glutamate or glutamine as an energy source in the presence but not the absence of Na. Monensin, a Na+/H+ antiporter, completely inhibited...Full Text Available
Rhizobium leguminosarum, biovar viceae, strain RCC1001 contains two glutamine synthetase activities, GSI and GSII. We report here the identification of glnA, the structural gene for GSI. A 2 kb fragment...Full Text Available
BackgroundAKXD recombinant inbred strains of mice have proven to be very useful in the identification of potential oncogenes and tumor suppressors involved in the development of...Full Text Available
The mouse is the leading organism for disease research. A rich resource of genetic variation occurs naturally in inbred and special strains owing to spontaneous mutations. However, one can also obtain...Full Text Available
The activities of some semisynthetic penicillins and cephalosporins have been tested against clinical strains of Staphylococcus aureus. The apparent activity in vitro varies with the method of testing...Full Text Available
Several dissimilatory, sulfate-reducing bacteria were isolated from the rumen fluid of sheep fed purified diets containing sulfate. One isolate, strain D, was selected for characterization. This organism...Full Text Available
In recent years, the interest in the use of bacteria for biological control of plant-pathogenic fungi has increased. We studied the possible side effects of coating barley seeds with the antagonistic...Full Text Available
BackgroundHyaluronic acid capsule plays a key role in Streptococcus pyogenes virulence. Circulation of mucoid or highly encapsulated strains has been related to...Full Text Available
Twelve Salmonella typhimurium strains resistant to broad-spectrum cephalosporins were isolated from cases of gastroenteritis during 1996 to 1998 in Russia, Hungary, and Greece. Resistance...Full Text Available
We ran a comparative analysis of all patients for whom a positive culture of Mycobacterium tuberculosis complex was available between April 2004 and October 2005 and whose HIV serology...Full Text Available
Mouse lines with behavioral phenotypes relevant to symptoms in neurodevelopmental disorders may provide models to test hypotheses about disease etiology and to evaluate potential treatments....Full Text Available
BackgroundThe Streptococcus pyogenes (group A streptococci, GAS) two-component signal transduction system CovRS has been described to be important for pathogenesis...Full Text Available
Septa can be demonstrated in sections of Escherichia coli strains B and B/r after fixation with acrolein and glutaraldehyde. The septum consists of an ingrowth of the cytoplasmic membrane...Full Text Available
The purpose of this study was to determine the occurrence and genotypic relatedness of Salmonella enterica isolates recovered from feed and fecal samples in commercial swine production...Full Text Available
Ninety percent of foxes fed commercial ERA vaccine in a specially designed bait developed rabies serum neutralizing antibodies. The vaccine bait did not cause clinical signs of rabies when consumed...Full Text Available
The ruminal selenomonad strain H18 grew rapidly (mu = 0.50 h-1) in a defined medium containing glucose, ammonia, purified amino acids, and sodium (95 mM); little if any ammonia was utilized as a nitrogen...Full Text Available
A copper-resistant strain (09906) of Pseudomonas fluorescens that was isolated from a citrus grove soil is being investigated as a biological control agent for Phytophthora root rot. Since citrus grove...Full Text Available
To evaluate the role of putative group A streptococcal virulence factors in the initiation of skin infections, we compared the adherence of a wild-type M49-protein skin-associated strain to that of...Full Text Available
Reverse genetics technology so far established for measles virus (MeV) is based on the Edmonston strain, which was isolated several decades ago, has been passaged in nonlymphoid cell lines, and is no...Full Text Available
Human cytomegalovirus (HCMV) in clinical material cannot replicate efficiently in vitro until it has adapted by mutation. Consequently, wild-type HCMV differ fundamentally from the passaged strains...Full Text Available
The activity of mice in their home cage is influenced greatly by the cycle of light and dark. In addition, home-cage activity shows remarkable time-dependent changes that result in a prominent temporal...Full Text Available
The properties of an atypical Brucella strain isolated from lymph node tissue of a cow slaughtered as a brucellosis reactor were examined. The organism was Gram negative and highly pleomorphic, existing...Full Text Available
A Monascus pilosus strain was selected for production of intracellular α-galactosidase. Optimum conditions for mycelial growth and enzyme induction were determined. Galactose...Full Text Available
In 2006, 3,531 fecal samples were collected from patients with diarrhea in Henan Province, China. A total of 467 (13.2%) Shigella strains were isolated and serotyped. Seventy-one...Full Text Available
Increase usage of magnesium components in the portable electronics industries has propelled considerable research interest on the development of magnesium forging. There have been some studies done in the area of sheet metal forming and forging of axis-symmetrical parts of magnesium alloys but there are very little work done on the plane strain backward extrusion of magnesium alloy. This paper deals with the analysis of plane strain extrusion of magnesium alloy, AZ31, using numerical modeling at different extrusion conditions of temperatures and friction coefficients. A commercially available finite element package, ANSYS/LSDYNA, was used in the finite element analysis. FE simulated results, material deformation, punch force and stress/strain distributions, were compared with actual experimental data. From the numerical analysis, a decrease in forging temperature from 300 C to 250 C will lead to a moderate increase in ...
Previous studies with a limited number of strains have indicated that there are two genotypes of yellow fever (YF) virus in Africa, one in west Africa and the other in east and central Africa. We have...Full Text Available
In vitro phagocytosis and intracellular survival of Campylobacter jejuni strain 2964 in mononuclear phagocytes were studied. The following three types of mononuclear phagocytes were used: a J774G8 peritoneal...Full Text Available
AbstractGenetic-variant analysis of rabies viruses provides the most sensitive epidemiologic tool for following the spread and persistence of these viruses in their wildlife hosts. Since...Full Text Available
The human opportunistic pathogen Pseudomonas aeruginosa strain PA14 is a multihost pathogen that can infect Arabidopsis. We found that PA14 pathogenesis in Arabidopsis involves the...Full Text Available
The clotting activity of Staphylococcus aureus strain 104 was purified 46,000-fold, but absolute purity was not achieved. Carbohydrate content of the purified material was not more than 5%. Elution...Full Text Available
A strain of Chromobacterium violaceum has been isolated which produces bacteriophage tail-like particles in high numbers. The extracellular morphology and the intracellular arrangement...Full Text Available
Mutant strains of the yeast Saccharomyces cerevisiae which lack functional Cu,Zn superoxide dismutase (SOD-1) do not grow aerobically unless supplemented with methionine. The molecular basis of this...Full Text Available
Three clinical strains (Escherichia coli Rio-6, E. coli Rio-7, and Enterobacter cloacae Rio-9) collected in 1996 and 1999 from hospitals in Rio de...Full Text Available
The effect of different nitrogen compounds on the induction of reduced nicotinamide adenine dinucleotide phosphate-nitrate reductase was examined in Neurospora crassa. Whereas in the wild-type strain...Full Text Available
Forty-eight mutants unable to reduce nitrate were isolated from "cowpea" Rhizobium sp. strain 32Hl and examined for nitrogenase activity in culture. All but two of the mutants had nitrogenase activity...Full Text Available
The studies reported here used genetic differences in susceptibility of C57BL/6N and C3H/HeN mice and exacerbation of the disease by nitrogen dioxide (NO/sub 2/) as tools in assessing the role of early host responses in the pathogenesis of MRM. The two strains did not differ in susceptibility to infection, but C3H/HeN mice were more susceptible to and had increased severity of lung lesions 14 days after intranasal inoculation as determined by 50% biological endpoints and morphometric analysis of tissues. Exposure to NO/sub 2/ for 4 hours prior to exposure to infectious aerosols exacerbated murine respiratory mycoplasmosis (MRM) by 7 days after exposure in both mouse strains. NO/sub 2/ appeared to affect host lung defense mechanisms responsible for limiting mycoplasmal growth in the lungs. The NO/sub 2/ exposure concentration required for this effect varied with the genetic background of the host, the dose of mycoplasmas administered, and the ...
Vulnerability to abused drugs is influenced by multiple genes unique to each drug as well as to risk genes for polydrug abuse. If several inbred mouse strains respond to different drugs similarly,...Full Text Available
BackgroundHepatitis A virus (HAV) strains detected in environmental and clinical samples were analysed to characterize the genotypes of HAV circulating in Greece. Fifty (50) sewage...Full Text Available
The overall objective of this project was to use molecular genetics to develop strains of bacteria with enhanced ability to remove sulfur from coal, and to obtain data that will allow the performance and economics of a coal biodesulfurization process to be predicted. (VC)
Purpose:Methicillin-resistant Staphylococcus aureus (MRSA) strains are commonly classified as hospital-acquired (HA) or community-acquired (CA). Typical HA-MRSA...Full Text Available
Escherichia coli strains producing extended-spectrum β-lactamases (ESBLs) are a major problem in many different hospitals worldwide, causing outbreaks as well as sporadic infections....Full Text Available
There has been great interest in understanding the methods by which collagen-based load-bearing tissue is constructed, grown and maintained in vertebrate animals. To date, the responsibility for this...Full Text Available
The authors calculated the stress-strain relation for elastomeric foam from an ab initio theory, which shows that the plateau and densification regions should be described by a hyperbola. The theory seems to agree reasonably well with experiment.
Enteropathogenic bacteria was isolated from 131 of 447 (29.4%) neotropical Panamanian lizards belonging to 34 species of seven families. Overall, 147 strains of bacteria were isolated comprising 26...Full Text Available
A Legionella-like organism (strain 1087-AZ-H) was isolated from a pleural-fluid specimen from a renal transplant patient undergoing immunosuppressive therapy. Growth characteristics and gas-liquid chromatography...Full Text Available
A Legionella-like organism, strain 1677-MI-H, was isolated from the bronchoscopy washings of a patient with pneumonia who had a 2-year history of progressive, chronic lymphocytic leukemia. The growth...Full Text Available
Three Legionella-like organisms were isolated from water from the cooling towers of two Australian institutions. The strains grew on buffered charcoal-yeast extract (BCYE) agar but not on BCYE agar...Full Text Available
A single large plasmid was isolated from multiplasmid-harboring strains Rhizobium leguminosarum 1001 and R. trifolii 5. These single plasmids, as well as the largest plasmid detectable in R. phaseoli...Full Text Available
To assess the practical significance of reported increases in the prevalence of vancomycin-susceptible strains of Neisseria gonorrhoeae on isolation of this organism, antibiotic-free chocolate agar...Full Text Available
Tetracycline-resistant Lactococcus lactis strains originally isolated from Polish raw milk were analyzed for the ability to transfer their antibiotic resistance genes in vitro, using...Full Text Available
Tarapur Atomic Power Station 3 and 4 is a 540 MWe Pressurized Heavy Water Reactor. It uses 37 - element natural Uranium dioxide (UO_2) fuel pellets encapsulated inside the cylindrical sheath and are welded to the end plate at each end. During an postulated accident in which part of the fuel bundle are exposed to very high temperature (no means of heat removal) and other are at lower temperature (coolant temperature) possibility of failure of end plate weld due of thermal stresses developed by these relative temperature cannot be ruled out. In this report an attempt is made to study behaviour of fuel bundle under different temperature loading. Modelling of 37 element fuel bundle was done in ANSYS FEM. System was analysed for various sets of temperature loading. The system was analysed for plasticity and creep as material nonlinearity. The total strain, creep strain and stress increase as the temperature increases in upper portion of fuel bundle ...
Four of seven human male subjects developed full penile erections when exposed to erotically stimulating motion pictures. Changes in penile size were detected by a mercury strain gauge transducer and...Full Text Available
The effectiveness of chemotherapy in human schistosomiasis varies from one area to another, and limited data from experimentally infected animals suggest inherent differences in the susceptibility...Full Text Available
The AKR mouse strain is characterized by a high incidence of spontaneous thymic lymphoma that appears in older animals (greater than 6 months of age) and is associated with novel provirus integrations...Full Text Available
Damage to the anterior talofibular ligament (ATFL) and cacaneofibular ligament (CFL) during ankle sprain may be linked to the development of osteoarthritis. Altered tibiotalar kinematics have...Full Text Available
This study investigated the impact of lifelong sedentariness on skeletal muscle mass and mitochondrial function. Thirty C57BL/6 strain mice (2 months) were randomly divided into three groups (young-Y;...Full Text Available
Isogenic strains containing insertional disruptions of 10 Haemophilus influenzae Rd genes were investigated for their effects on the susceptibility of the organism to various classes...Full Text Available
A nodulation plasmid, pRtr-514a, of molecular size 180 megadaltons (Mdal) was identified in Rhizobium trifolii strain NZP514. This plasmid was absent in both spontaneous and heat-cured Nod- derivatives...Full Text Available
Supercoiled double-stranded DNA molecules (plasmids) were isolated from plants infected with three laboratory strains of western aster yellows mycoplasma-like organism (AY-MLO) by using cesium chloride-ethidium...Full Text Available
Promising approaches to produce higher alcohols, e.g., isobutanol, using Escherichia coli have been developed with successful results. Here, we translated the isobutanol process from shake flasks to a 1-L bioreactor in order to characterize three E. coli strains. With in situ isobutanol removal from the bioreactor using gas stripping, the engineered E. coli strain (JCL260) produced more than 50?g/L in 72?h. In addition, the isobutanol production by the parental strain (JCL16) and the high isobutanol-tolerant mutant (SA481) were compared with JCL260. Interestingly, we found that the isobutanol-tolerant strain in fact produced worse than either JCL16 or JCL260. This result suggests that in situ product removal can properly overcome isobutanol toxicity in E. coli cultures. The isobutanol prod...
A novel, quantitative method for detecting poly-3-hydroxybutyrate (PHB) amounts in viable cells was developed to allow for high-throughput screening of mutant libraries. The staining technique was demonstrated...Full Text Available
In chemostat culture, the virulence of two strains of Legionella pneumophila was shown to be significantly (P < 0.05) reduced when the culture temperature was lowered from 37 to 24 degrees C....Full Text Available
A Staphylococcus strain was inoculated on the top and cut surfaces of freshly baked Southern custard pies which were then packaged in a pasteboard carton and held at 30 C. Daily plate...Full Text Available
Clindamycin concentrations in gingival crevicular fluid and in blood were determined over a 7-h period and were related to the minimal inhibitory concentrations of this agent for 340 bacterial strains...Full Text Available
Francisella tularensis requires iron (Fe) for growth, but the biologic sources of Fe for this organism are largely unknown. We found that Francisella sp. growing in...Full Text Available
It was found that neither the enzymes of the grapes nor those of wine yeast Saccharomyces ellipsoideus strain 223 attacked the higher polysaccharides present in corn syrups. The alcohol...Full Text Available
Various factors affecting the aggregation of Actinomyces naeslundii strain 12104 were studied. When the pH of glucose-supplemented growth medium fell below 5.5, the cells aggregated and formed microbial...Full Text Available
Excitonic transitions in metalorganic vapor phase epitaxially grown In_xGa_1_-_xP/In_0_._4_8(Al_0_._7Ga_0_._3)_0_._5_2P strained single quantum-well structures are characterized using low-temperature photoluminescence and photoluminescence excitation (PLE) spectroscopies. The structures consist of several uncoupled quantum wells with thicknesses between 1.2 and 11.3 nm, and compositions x of 0.48 (nominally lattice matched) and 0.56 (#approx#0.6% biaxial compressive strain). The photoluminescence spectra exhibit intense peaks over the wavelength range 550--650 nm, with linewidths between 7 and 23 meV depending on the well thickness. The PLE spectra reveal strong heavy-hole and light-hole transitions, as well as higher-order (n=2) transitions in the thicker wells. The heavy-hole/light-hole splitting shows little dependence on well thickness in the strained structures, indicating a relatively large conduction band offset of ...
Highly pathogenic avian influenza and in particular the H5N1 strain has resulted in the culling of millions of birds and continues to pose a threat to poultry industries worldwide. The recent outbreak...Full Text Available
A Klebsiella pneumoniae epidemic strain that coproduced carbapenemase KPC-2 (K. pneumoniae carbapenemase 2) and 16S rRNA methylase ArmA has emerged in Poland. Four...Full Text Available
Phagocytosis and intracellular killing of two strains of Escherichia coli and a Staphylococcus saprophyticus by polymorphonuclear neutrophils (PMN) in pooled sterile urine at three osmolalities (800,...Full Text Available
Chemoprevention strategies to prevent the development of lung cancer in at-risk individuals are a key component in disease management. In addition to being highly effective, an ideal chemopreventive...Full Text Available
Microstructure evolution under hot deformation was investigated in compression of a magnesium alloy AZ31 at 673 K (0.73T{sub m}). Two kinds of samples were machined along the parallel and transverse direction of the extruded rods. New fine grains are evolved at corrugated grain boundaries at low strains and developed rapidly in grain interiors in the medium range of strain, finally leading to a roughly full evolution of equiaxial fine grains. Kink bands are evolved at corrugated grain boundaries and in grain interiors at low strains. The boundary misorientation of kink band increases rapidly with increasing strain. These characteristics of new grain evolution process are not changed by the orientation of the samples, while the flow behaviors clearly depend on it. It is concluded that new grain evolution can be controlled by a deformation-induced continuous reaction resulting in grain fragmentation by ...
Current methods for drug susceptibility testing of Mycobacterium tuberculosis are either costly or slow. As the prevalence of multidrug-resistant strains increases, the need for fast,...Full Text Available
Haemophilus parasuis causes polyserositis in swine. Fifteen serovars have been characterized by immunodiffusion test, but many field strains are not typeable. Isolates (n...Full Text Available
The hierarchical arrangement of collagen and mineral into bone tissue presumabley maximizes fracture resistance with respect to the predominant strain mode in bone. Thus, the ability of cortical...Full Text Available
Splenectomy or pretreatment of adult hamsters with cyclophosphamide (Cytoxan) increased the lethality of the TC-83 vaccine strain of Venezuelan encephalitis virus (VEE), inoculated subcutaneously, from 12% for normal hamsters to 75 and 76% respectively. A...
Potential uses of foliage and bark wastes of E. ('Mysore') hybrid in southern India for the production of cineole and oxalic acid respectively are discussed. Only certain strains are cineole-rich and these are being successfully propagated vegetatively at the authors' laboratory.
BackgroundThe emergence of plasmid-mediated carbapenemases, such as NDM-1 in Enterobacteriaceae is a major public health issue. Since they mediate resistance to...Full Text Available
The most characteristic features of the Lyme disease pathogens, the Borrelia burgdorferi sensu lato (s.l.) group, are their ability to invade tissues and to circumvent the immune defenses...Full Text Available
Penicillium crustosum is common in food and feed both in subtropical and temperate regions. Recently, it has also been found occurring frequently in glacier ice, sea ice and sea water of Arctic regions of Svalbard. The aim of the study was to compare isolates of the same fungal species from widely different habitats and geographic regions to see if the nutritional physiology and the profile of secondary metabolites were consistent or depended on the isolation source. All 121 strains examined produced the following families of secondary metabolites: penitrems (100%), roquefortines (100%), terrestric acids (99.2%) and viridicatols (100%), whereas 81 of 83 Arctic isolates additionally produced andrastin A. However, only 8 of 38 non-Arctic isolates produced detectable andrastin A. The quantitative profiles of 96 strains were compared using cluster, principal component and correspondence analyses. There was no clear grouping of Arctic versus ...
In 2000 to 2001, 2003 to 2004, and 2005 to 2006, three outbreaks of Salmonella enterica serovar Enteritidis were linked with the consumption of raw almonds. The S....Full Text Available
Hexachlorocyclohexane (HCH) has been used extensively against agricultural pests and in public health programs for the control of mosquitoes. Commercial formulations of HCH consist of a mixture of four...Full Text Available
Carbohydrate/citrate cometabolism in Lactococcus lactis results in the formation of the flavor compound acetoin. Resting cells of strain IL1403(pFL3) rapidly consumed citrate while...Full Text Available
Regulation of glucose isomerase synthesis was studied in Thermoanaerobacter strain B6A, which fermented a wide variety of carbohydrates including glucose, xylose, lactose, starch, and...Full Text Available
The effects of sennosides on colonic motility were investigated in eight conscious dogs chronically fitted with two strain gauge transducers in the proximal colon, an intracolonic silicone catheter...Full Text Available
This book contains over 20 selections. Some of the titles are: Continuum damage mechanics studies on the dynamic fracture of concrete; Dynamic compressive strength of cementitious materials; Rate-sensitivity of mode I and mode II fracture concrete; and An impact damage model of concrete.
A total of 150 strains of staphylococci, clinically isolated, were tested for sensitivity to ovotransferrin (conalbumin). Among these, all the 50 coagulase-positive, mannitol-positive, and deoxyribonuclease-positive...Full Text Available
We report a patient with neonatal meningitis caused by a CTX-M-1–producing Escherichia coli K1 strain. The influence of CTX-M production on virulence was investigated in cell...Full Text Available
The pharynx is the primary reservoir for strains of group A Streptococcus (GAS) associated both with pharyngitis (streptococcal sore throat) and with invasive or “flesh-eating”...Full Text Available
Biodegradation/solubilization of coal is described. The degradation of dibenzothiophene by two bacterial strains is reported. The effects of adding salicylate to the treatments was also investigated. 2 figs., 5 tabs. (CBS)
Abstract A bacteriocin-producing Streptococcus bovis strain (HC5) outcompeted a sensitive strain (JB1) before it reached stationary phase (pH 6.4), even though it grew 10% slower and cell-free bovicin HC5 could not yet be detected. The success of bacteriocin-negative S. bovis isolates was enhanced by the presence of another sensitive bacterium (Clostridium sticklandii SR). PCR based on repetitive DNA sequences indicated that S. bovis HC5 was not simply transferring bacteriocin genes to S. bovis JB1. When the two S. bovis strains were coinoculated into minimal medium, bacteriocin-negative isolates predominated, and this effect could be explained by the longer lag time (0.5 vs. 1.5 h) of S. bovis HC5. If the glucose concentration of the minimal medium was increased from 2 to 7 mg mL-1, the e...
An assay to measure the rate of enzymatic formation of 3-methylindole (3MI) from indoleacetic acid (IAA) in Lactobacillus sp. strain 11201 was developed. The reaction mixture contained 50 micrograms...Full Text Available
A total of 193 bacterial strains were tested for their susceptibilities to 14 antimicrobial agents. Penicillin G was active at 2 U/ml against 98% of the oral isolates. Other antibiotics with good activity...Full Text Available
The Wistar Kyoto (WKY) rat strain is a putative genetic model of comorbid depression and anxiety. Previous research showing increased κ-opioid receptor (KOR)...Full Text Available
A strain of Vibrio sp. isolated from marine sediments produced large quantities of bright red pigments that could be used to dye many fibers including wool, nylon, acrylics,...Full Text Available
BackgroundThe Gram-negative, xylem-limited phytopathogenic bacterium Xylella fastidiosa is responsible for causing economically important diseases in grapevine,...Full Text Available
To study the occurrence and distribution of various strains of Haemophilus parasuis in southern Ontario swine, organisms isolated from healthy swine, from specific pathogen-free and conventional herds,...Full Text Available
Enzootic Glassers's disease was investigated to study the epidemiology of the disease strains on a farm where it presented a problem. Restriction endonuclease fingerprinting (REF) analysis technique...Full Text Available
The sensitivities to cefuroxime and cephradine of potentially pathogenic bacteria isolated in two British general hospitals comprising 900 beds have been assessed. In a three-month period 2537 strains...Full Text Available
Reciprocal mass crosses and back-crosses were performed between two homogeneous strains of the housefly (Musca domestica L.), representing the extremes in susceptibility and resistance...Full Text Available
Plumbagin is found in many herbal plants and inhibits the growth of various bacteria. Escherichia coli strains are relatively resistant to this drug. The mechanism of resistance is...Full Text Available
BackgroundCompared to outbred Sprague Dawley (SD) rats, inbred Brown Norway (BN) rats exhibit less prepulse inhibition of startle (PPI) at long prepulse intervals,...Full Text Available
The distribution of 20 variable regions resulting from insertion-deletion events in the genomes of the tubercle bacilli has been evaluated in a total of 100 strains of Mycobacterium tuberculosis,...Full Text Available
The possibility of improving the cold formability of wrought magnesium alloys is considered in light of their good hot forming characteristics. Magnesium alloy AZ31B sheet is selected as a model system. Parameters affecting formability, such as strain hardening rate, strain rate sensitivity, and the degree of anisotropy are examined systematically by conducting tensile tests over a range of temperatures (room temperature to 250 C) and strain rates (1 x 10{sup -5} to 0.1 s{sup -1}). The plastic anisotropy and deformation texture evolution are examined in samples aligned with the sheet rolling and transverse directions. Polycrystal plasticity simulations using a viscoplastic self-consistent (VPSC) formulation are used to model the observed anisotropy and texture evolution. The adjustable parameters in the model are the relative critical resolved shear stresses of the dislocation mechanisms known to operate within magnesium. ...
A flexible, steerable tube (distal end) of an endoscope for the application in the laparoscopic surgery has been analyzed by means of the finite-element-method (FEM). The unusual mechanical and thermal features of the used shape memory alloy (SMA) of NiTi were taken in account. The analyses showed that the strains remain in the super-elastic region up to the maximum bending of 90 and no plastic deformations occur. The application of the shape optimization (CAO) made possible finding the optimal structure of the distal end and therefore powerful reducing the maximum strains in the critical regions. (orig.)
The deferred luminescence (isothermal luminescence -ITL- and thermoluminescence - RTL) emitted by Chlorella cells after #gamma# irradiation at 77 K has been investigated. The decay kinetics of ITL as well as the effect of illumination of both ITL and RTL show that trapped electrons take part in the recombination reactions which give rise to both emissions, and that ITL can be attributed to electron tunnelling. Most strains of Chlorella studied present similar RTL glow curves, the only exceptions found being Chlorella vulgaris (green and bleached strains).
It is postulated that a break of a thin-walled pipe does not cause a subsequent break in the pipe in the vicinity of a plastic hinge even when the wall is weakened by a 60 circumferential crack of a depth of 30% of the wall thickness on the tension side. This pipe behavior is the result of plastic buckling in the compression side and applies to pipes of diameter-to-thickness ratio larger than 20. For this type of pipe, the axial strains decrease with increasing diameter-to-thickness ratio in the tension side. As the pipe is only loaded in one direction, there is no cyclic behavior that can trigger a subsequent break. (orig.)
The excess energy of several III-V and II-VI strained-layer semiconductor superlattices (AC)_p(BC)_p is studied as a function of the repeat period p and orientation G=[001], [110], [111], and [201], using first-principles calculations. We discover a number of universal features, including the predicted instability for nearly all p's and G's with respect to bulk disproportionation, the identification of chalcopyrite as a metastable ordered structure, and the stability of all thin epitaxial [110] and [201] and most common-anion [001] superlattices relative to coherent phase separation.
We investigate the formation of nanostructures in 2D strained alloys on face centered cubic (111) surfaces by means of equilibrium Monte Carlo simulations. In the framework of an off-lattice model, we consider one monolayer of two bulk-immiscible adsorbates A and B with negative and positive misfit relative to the substrate, respectively. Simulations show that the adsorbates partly self-organize into island or stripe-like patterns. We show how these structures depend on the relative misfits, interaction, and concentration of components. The morphology is quite different for phase separation and intermixing regimes.
A hysteretic subcritical period-doubling bifurcation is observed in the nonlinear strain dynamics of a magnetostrictive oscillator. The dynamic strain response of the magnetostrictive oscillator was observed with a high-resolution fiber optic interferometer. The effects of low-frequency modulation and band-limited stochastic fluctuations on such a bifurcation are investigated. Power spectral density measurements show that for an optimal value of externally injected noise the signal-to-noise ratio of a low-frequency modulation signal is enhanced by greater than 14 dB, thus indicating the first experimental observation of stochastic resonance near a bistable period-doubling bifurcation. 10 refs., 7 figs.
An Al-5%Mg-0.18%Mn-0.2%Sc-0.08%Zr-0.002%Be was subjected to equal-channel angular extrusion up to true strains of #approx#3 and #approx#8, that resulted in the formation of partially recrystallized and fully recrystallized structure, respectively. It was shown that the alloy with partially recrystallized structure exhibits highest strength and ductility. The material with fully recrystallized structure showed lowest fatigue crack growth rate and highest value of fracture toughness. Reasons of this unusual effect of microstructure on crack propagation resistance under fatigue are discussed.
In acute liver failure following hepatitis, toxic insults, or after major liver surgery, there is an increased bacterial translocation from the gut. This may explain some of the infectious complications seen in these conditions. To elucidate mechanisms and find possible preventive measures, we investigated the effect of rectal administration of arginine and probiotic bacteria (Lactobacillus spp.) on bacterial translocation and the extent of liver failure. Sprague-Dawley rats were used and five different Lactobacillus strains (Lb. reuteri R2LC, Lb. rhamnosus DSM 6594 (= strain 271), Lb. plantarum DSM 9843 (= strain 299v), Lb. fermentum 8704:3 (= strain 245), and Lb. reuteri (= strain 108) were administered rectally once daily for 8 days with and without 2% arginine. Acute liver injury (ALI) was induced on the eighth day by intraperitoneal injection of D-galactosamine (1.1 g/kg body ...
We demonstrated direct assimilation of cellooligosaccharide using Escherichia coli displaying beta-glucosidase (BGL). BGL from Thermobifida fusca YX (Tfu0937) was displayed on the E. coli cell surface using a novel anchor protein named Blc. This strain was grown successfully on 0.2% cellobiose, and the optical density at 600 nm (OD(600)) was 1.05 after 20 h. PMID:21742905
''Paraquat lung'' which is complicated with paraquat poisoning has been a lethal pulmonary pathology presenting intra-alveolar fibrosis, but an effective therapy has not been developed so far. We hypothesized that the type II alveolar cells producing surfactant were damaged by paraquat which was actively accumulated through out the blood by alveolar epithelial cells. To prove this hypothesis, we examined the effect of an intratracheal administration of an artificial lung surfactant (surfacten, Mitsubishi Tanabe Pharma Corporation, Osaka) on mortality in a model of murine paraquat poisoning. Paraquat was given intramuscularly 3 days after the intratracheal surfactant administration. The mice used were C57BL/6J strain and Balb/C strain. The lethal dose, 50% (LD50), of paraquat was about 28 mg/kg in the C57BL/6J strain and about 9 mg/kg in the Balb/C strain, respectively. Mortalities of paraquat poisoning ...
An experimental technique has been developed to examine the interaction between deformation and the exposure of certain high temperature structural alloys to oxidizing molten salt environments. The experimental program involved performing a series of long-term tensile tests over a wide range of strain rates. Fracture strain reduction in area and ultimate strength (UTS) were monitored as parameters indicative of an alloy's susceptibility to environmental degradation. For Incoloy Alloy 800 tested at 600/sup 0/C in the salt medium and at initial strain rates between 2 x 10/sup -7/ sec/sup -1/ and 1 x 10/sup -5/ sec/sup -/1 no appreciable loss of ductility, as measured by reduction in area, was observed relative to control specimens tested in air at the same temperature and strain rates. Similarly, fracture strain and UTS were essentially unaffected by exposure to the oxidizing ...
Dynamic recrystallization (DRX) is the main softening mechanism of magnesium alloy AZ31B in hot deformation. Theoretically, in the flow rule the atomic diffusibility and the driving force of dislocation migration are dependent on the temperature, and the dislocation density and the cumulation of grain boundary energy are dependent on the strain rate. The peak stress will appear when the flow driving force and resistance force reach a balance, after which the stress descending will take place due to recrystallization fraction. Since the DRX is a thermally activated process, the recrystallized volume fraction can be regarded as the function of strain through Avrami equation. Based on this idea, the paper proposes a new constitutive model characterizing dynamic recrystallization for magnesium alloy AZ31B. The model is described by a peak stress and a strain softening rate, in which the peak stress depends only on ...