WorldWideScience
1

Bacterial chemoreceptors: high-performance signaling in networked arrays  

UK PubMed Central (United Kingdom)

Chemoreceptors are crucial components in the bacterial sensory systems that mediate chemotaxis. Chemotactic responses exhibit exquisite sensitivity, extensive dynamic range and precise adaptation....Full Text Available

2008-01-01

2

Surface structure recognized for covalent modification of the aspartate receptor in chemotaxis.  

UK PubMed Central (United Kingdom)

The aspartate receptor involved in chemotaxis is modified by methyl esterification at four distinct glutamate residues during the adaptive response of this receptor. To explain the high degree of specificity...Full Text Available

1986-09-01

3

Quantitation of microbial products and their effectiveness in enhanced oil recovery. Final report  

Energy Technology Data Exchange (ETDEWEB)

A three-dimensional, three-phase, multiple-component numerical simulator was developed to investigate transport and growth of microorganisms in porous media and the impacts of microbial activities on oil recovery. The microbial activities modeled in this study included: (1) growth, retention, chemotaxis, and end product inhibition of growth, (2) the formation of metabolic products, and (3) the consumption of nutrients. Major mechanisms for microbial enhanced oil recovery (MEOR) processes were modeled as follows: (1) improvement in sweep efficiency of a displacement process due to in situ plugging of highly-permeable production zones by cell mass or due to improved mobility control achieved by increasing the viscosity of the displacing fluid with a biopolymer, and (2) solubilization and mobilization of residual oil in porous media due to the reduction of the interfacial tension between oleic and aqueous phases by the production of a biosurfactant. The numerical ...

1995-02-01

4

Quantification of antibiotic drug potency by a two-compartment radioassay of bacterial growth  

Energy Technology Data Exchange (ETDEWEB)

The two-compartment radioassay for microbial kinetics based on continuous measurement of the {sup 14}CO{sub 2} released by bacterial metabolism of 14C-labeled substrate offers a valuable approach to testing the potency of antimicrobial drugs. By using a previously validated radioassay with gram-positive and gram-negative bacteria, a group of protein synthesis inhibitors was evaluated for their effect on microbial growth kinetics. All tested drugs induced changes in both the slopes and intercepts of the growth curves. An exponential growth model was applied to quantify the drug effect on the processes of bacterial {sup 14}CO{sub 2} liberation and cell generation. The response was measured in terms of a generation rate constant. A linear dependence of the generation rate constant on the dose of spectinomycin was observed with Escherichia coli. Sigmoidal-shaped curves were found in the assays of chloramphenicol and ...

1990-06-01

5

Involvement of the chemokine-like receptor GPR33 in innate immunity?  

UK PubMed Central (United Kingdom)

Chemokine receptors control leukocyte chemotaxis and cell-cell communication but have also been associated with pathogen entry. GPR33, an orphan member of the chemokine-like receptor family,...Full Text Available

2010-05-28

6

Eosinophils Utilize Multiple Chemokine Receptors for Chemotaxis to the Parasitic Nematode Strongyloides stercoralis  

UK PubMed Central (United Kingdom)

Protective innate immunity to the nematode Strongyloides stercoralis requires eosinophils in the parasite killing process. Experiments were performed to determine if an extract of S....Full Text Available

2009-10-01

7

A discrete cell model with adaptive signalling for aggregation of Dictyostelium discoideum.  

UK PubMed Central (United Kingdom)

Dictyostelium discoideum (Dd) is a widely studied model system from which fundamental insights into cell movement, chemotaxis, aggregation and pattern formation can be gained. In this system aggregation...Full Text Available

1997-03-29

8

Bacterial conjunctivitis  

UK PubMed Central (United Kingdom)

Clinical questionWhat is the best treatment for bacterial conjunctivitis?ResultsTopical antibiotics expedite recovery from bacterial conjunctivitis....Full Text Available

2010-01-01

9

Abnormalities of polymorphonuclear leukocyte function associated with a heritable deficiency of high molecular weight surface glycoproteins (GP138): common relationship to diminished cell adherence.  

UK PubMed Central (United Kingdom)

Investigations of polymorphonuclear leukocyte (PMN) function were performed in a 5-yr-old white female with delayed umbilical cord separation, impaired pus formation, and a severe defect of PMN chemotaxis....Full Text Available

1984-08-01

10

Simultaneous quantitative measurement of biodegradability and toxicity of environmental chemicals  

International Nuclear Information System (INIS)

Investigations were made on the biodegradability and bacterial toxicity of chemicals. The intention was to obtain data necessary for estimating and judging the behaviour of these chemicals during aerobic biological waste water treatment. The course of biodegradation and toxicity with time and concentration could be measured, quantified and described. As test procedure, the respirometric dilution method was used. This method is based on a die away test with continuous measuring of the oxygen used for biochemical oxidation processes. The course of the oxygen demand with time and concentration shows the biodegradation and toxicity patterns of the tested chemical. A variety of household and industrial chemicals were investigated. One group of substances were microbiocides, some of which showed toxic effects at concentrations less than 20 mg/l while others were biodegradable even at concentrations of 200 mg/l. Another group of test chemicals were ...

1994-04-01

11

Factors Linked to Bacterial Vaginosis in Nonpregnant Women  

UK PubMed Central (United Kingdom)

Objectives. The purposes of this study were to test the hypothesis that vaginal douching is linked to bacterial vaginosis in both symptomatic and asymptomatic women and to identify...Full Text Available

2001-10-01

16

Impregnation of silver nanoparticles into bacterial cellulose for antimicrobial wound dressing  

British Library Electronic Table of Contents (United Kingdom)

Bacterial cellulose was produced by Acetobacter xylinum (strain TISTR 975). Bacterial cellulose is an interesting material for using as a wound dressing since it provides moist environment to a wound resulting in a better wound healing. However, bacterial cellulose itself has no antimicrobial activity to prevent wound infection. To achieve antimicrobial activity, silver nanoparticles were impregnated into bacterial cellulose by immersing bacterial cellulose in silver nitrate solution. Sodium borohydride was then used to reduce the absorbed silver ion (Ag+) inside of bacterial cellulose to the metallic silver nanoparticles (Ag0). Silver nanoparticles displayed the optical absorption band around 420nm. The red-shift and broadening of the optical absorption band was observed when the mole rat...

2008-01-01

17

The effect of aqueous composition on diffusion coefficient in bentonite  

International Nuclear Information System (INIS)

The diffusion coefficients (De) in bentonite were measured to understand and quantify the influence of groundwater chemistry such as ionic strength and to quantify the alteration of smectite mineralogical transformations. (author)

2009-12-01

18

Toll-like receptor 2 polymorphism and gram-positive bacterial infections after liver transplantation  

British Library Electronic Table of Contents (United Kingdom)

Abstract Toll-like receptor 2 (TLR2) is an immune sensor for gram-positive bacterial cell wall components. Single-nucleotide polymorphisms (SNPs) in the TLR2 gene that impair its function may, therefore, influence the risk and outcomes of gram-positive bacterial infections. In a cohort of 694 liver transplant recipients, we assessed the TLR2 SNP that is translated into an amino acid substitution of arginine for glutamine at position 753 (R753Q), and we found that its presence was associated with the clinical characteristics and outcomes of gram-positive bacterial infections. The proportions of patients with the TLR2 R753Q SNP did not significantly differ between those with gram-positive bacterial infections and those without gram-positive bacterial infections (9.6% versus 9.6%, P = 0.999)....

2011-01-01

19

Ovis aries CR4 is involved in Mannheimia haemolytica leukotoxin-induced cytotoxicity  

British Library Electronic Table of Contents (United Kingdom)

Pneumonia caused by Mannheimia haemolytica is an important disease of domestic sheep (DS, Ovis aries) and cattle (BO). M. haemolytica is a normal commensal of the upper respiratory tract in ruminants, but during stress and viral infection it breaches the host innate mucosal defense and descents into lungs causing fibrinous pleuropneumonia. Leukotoxin (Lkt) produced by M. haemolytica is cytolytic to all subsets of ruminant leukocytes. Earlier, we and others have shown that DS and BO LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) can mediate Lkt-induced cytolysis. It is not clear whether CR4 (CD11c/CD18), which is involved in chemotaxis, phagocytosis and regulates host immune response can also mediate Lkt-induced cytolysis in ruminants. The host innate immune response to M. haemolytica is poorly ...

2010-01-01

20

The bacterial signal indole increases epithelial-cell tight-junction resistance and attenuates indicators of inflammation  

UK PubMed Central (United Kingdom)

Interkingdom signaling is established in the gastrointestinal tract in that human hormones trigger responses in bacteria; here, we show that the corollary is true, that a specific bacterial signal,...Full Text Available

2010-01-05

21

The Mammalian Neuroendocrine Hormone Norepinephrine Supplies Iron for Bacterial Growth in the Presence of Transferrin or Lactoferrin  

UK PubMed Central (United Kingdom)

Norepinephrine stimulates the growth of a range of bacterial species in nutritionally poor SAPI minimal salts medium containing 30% serum. Addition of size-fractionated serum components to SAPI...Full Text Available

2000-11-01

22

Studying bacterial transcriptomes using RNA-seq  

UK PubMed Central (United Kingdom)

Genome-wide studies of bacterial gene expression are shifting from microarray technology to second generation sequencing platforms. RNA-seq has a number of advantages over hybridization-based techniques,...Full Text Available

2010-10-01

23

Stable-Carbon-Isotope Composition of Fatty Acids in Hydrothermal Vent Mussels Containing Methanotrophic and Thiotrophic Bacterial Endosymbionts  

UK PubMed Central (United Kingdom)

Fatty acid biomarker analysis coupled with gas chromatography-isotope ratio mass spectrometry was used to confirm the presence of methanotrophic and thiotrophic bacterial endosymbionts in the tissues...Full Text Available

1998-01-01

24

Separation of the bacterial species, Escherichia coli, from mixed-species microbial communities for transcriptome analysis  

UK PubMed Central (United Kingdom)

BackgroundThe study of bacterial species interactions in a mixed-species community can be facilitated by transcriptome analysis of one species in the community using cDNA microarray...Full Text Available

25

Sensitivity of Freshly Isolated Bacterial Pathogens to Certain Antibiotics and Nitrofurazone  

UK PubMed Central (United Kingdom)

The results of antibiotic tests on bacterial pathogens freshly isolated from avian tissues and bovine milk are presented. Coliform isolates from the avian species showed an increased resistance to...Full Text Available

1969-01-01

26

Racial differences in cervical cytokine concentrations between pregnant women with and without bacterial vaginosis  

UK PubMed Central (United Kingdom)

We have examined the association between cytokine, chemokine and growth factor concentrations with bacterial vaginosis (BV) in pregnant white and black women. A nested case-control analysis...Full Text Available

2008-07-01

27

Pretreatment with the gram-positive bacterial cell wall molecule peptidoglycan improves bacterial clearance and decreases inflammation and mortality in mice challenged with Pseudomonas aeruginosa  

UK PubMed Central (United Kingdom)

The objective of this study was to determine if inflammatory tolerance and enhancement of innate immune function could be induced by the gram-positive cell wall component peptidoglycan (PGN)....Full Text Available

2008-10-01

28

Persistence of Free-Living Protozoan Communities across Rearing Cycles in Commercial Poultry Houses ?  

UK PubMed Central (United Kingdom)

The introduction and survival of zoonotic bacterial pathogens in poultry farming have been linked to bacterial association with free-living protozoa. To date, however, no information is available on...Full Text Available

2011-03-01

29

Pericardiectomy for Pleuropericardial Effusion Complicating Bacterial Pneumonia  

UK PubMed Central (United Kingdom)

Severe pericardial effusion is a rare complication of bacterial pneumonia and it usually disappears under medical treatment. Herein we report a case of a girl with a congenital immunodeficient syndrome...Full Text Available

2010-01-01

30

Nonlinearity in bacterial population dynamics: Proposal for experiments for the observation of abrupt transitions in patches  

UK PubMed Central (United Kingdom)

An explicit proposal for experiments leading to abrupt transitions in spatially extended bacterial populations in a Petri dish is presented on the basis of an exact formula obtained through an analytic...Full Text Available

2008-12-02

31

Neonatal E. coli infection alters glial, cytokine, and neuronal gene expression in response to acute amphetamine in adolescent rats  

UK PubMed Central (United Kingdom)

Neonatal bacterial infection in rats alters the responses to a variety of subsequent challenges later in life. Here we explored the effects of neonatal bacterial infection on a subsequent drug...Full Text Available

2010-04-19

32

Lethal protein produced in response to competition between sibling bacterial colonies  

UK PubMed Central (United Kingdom)

Sibling Paenibacillus dendritiformis bacterial colonies grown on low-nutrient agar medium mutually inhibit growth through secretion of a lethal factor. Analysis of secretions reveals...Full Text Available

2010-04-06

33

Interactions of Antibiotics and Methanolic Crude Extracts of Afzelia Africana (Smith.) Against Drug Resistance Bacterial Isolates  

UK PubMed Central (United Kingdom)

Infection due to multidrug resistance pathogens is difficult to manage due to bacterial virulence factors and because of a relatively limited choice of antimicrobial agents. Thus, it is imperative to...Full Text Available

34

Improved Understanding of the Bacterial Vaginal Microbiota of Women before and after Probiotic Instillation  

UK PubMed Central (United Kingdom)

The vaginal bacterial microbiota of 19 premenopausal women was examined by PCR-denaturing gradient gel electrophoresis (DGGE) and sequencing of the V2-V3 region of the 16S rRNA gene. Ten of the women...Full Text Available

2003-01-01

35

IL-6-Dependent Mucosal Protection Prevents Establishment of a Microbial Niche for Attaching/Effacing Lesion-Forming Enteric Bacterial Pathogens1  

UK PubMed Central (United Kingdom)

Enteric infections with attaching/effacing lesion-inducing bacterial pathogens are a worldwide health problem. A murine infection model with one such pathogen, Citrobacter rodentium,...Full Text Available

2008-05-15

36

Generation of Novel Bacterial Regulatory Proteins That Detect Priority Pollutant Phenols  

UK PubMed Central (United Kingdom)

The genetic systems of bacteria that have the ability to use organic pollutants as carbon and energy sources can be adapted to create bacterial biosensors for the detection of industrial pollution....Full Text Available

2000-01-01

37

FIRST TRIMESTER BACTERIAL VAGINOSIS, INDIVIDUAL MICROORGANISM LEVELS AND RISK OF SECOND TRIMESTER PREGNANCY LOSS AMONG URBAN WOMEN  

UK PubMed Central (United Kingdom)

ObjectiveTo examine the role of first trimester bacterial vaginosis (BV) and level of BV-associated microorganisms diagnosed using the Nugent’s Gram stain...Full Text Available

2007-11-01

38

Evaluations of bacterial contaminated full thickness burn wound healing in Sprague Dawley rats Treated with Tualang honey  

UK PubMed Central (United Kingdom)

Aim:The effect of Tualang honey on wound healing in bacterial contaminated full-thickness burn wounds was evaluated in 36 male Sprague Dawley rats.Materials...Full Text Available

2011-01-01

39

Euryarchaeal ?-CASP Proteins with Homology to Bacterial RNase J Have 5?- to 3?-Exoribonuclease Activity*  

UK PubMed Central (United Kingdom)

In the Archaea only a handful of ribonucleases involved in RNA processing and degradation have been characterized. One potential group of archaeal ribonucleases are homologues of the bacterial RNase...Full Text Available

2010-06-04

40

Comparison of oral and vaginal metronidazole for treatment of bacterial vaginosis in pregnancy: impact on fastidious bacteria  

UK PubMed Central (United Kingdom)

BackgroundBacterial vaginosis (BV) is a common condition that is associated with preterm birth and acquisition of complex communities of vaginal bacteria that include several fastidious...Full Text Available

41

Comparative genomics of the bacterial genus Listeria: Genome evolution is characterized by limited gene acquisition and limited gene loss  

UK PubMed Central (United Kingdom)

BackgroundThe bacterial genus Listeria contains pathogenic and non-pathogenic species, including the pathogens L. monocytogenes and L. ivanovii,...Full Text Available

42

Bacterial Particle Endocytosis by Epithelial Cells Is Selective and Enhanced by Tumor Necrosis Factor Receptor Ligands?  

UK PubMed Central (United Kingdom)

Bacterial pathogens use virulence strategies to invade epithelial barriers, but active processes of epithelial cells may also contribute to the endocytosis of microbial particles. To focus on the latter,...Full Text Available

2009-03-01

43

Bacterial Oxidation of Sulfide Minerals in Column Leaching Experiments at Suboptimal Temperatures  

UK PubMed Central (United Kingdom)

The purpose of the work was to quantitatively characterize temperature effects on the bacterial leaching of sulfide ore material containing several sulfide minerals. The leaching was tested at eight...Full Text Available

1992-02-01

44

Bacterial Fouling in a Model Core System  

UK PubMed Central (United Kingdom)

We have used a sintered glass bead core to simulate the spaces and surfaces of reservoir rock in studies of the bacterial plugging phenomenon that affects waterflood oil recovery operations. The passage...Full Text Available

1985-03-01

45

Bacterial Competition for Human Nasal Cavity Colonization: Role of Staphylococcal agr Alleles  

UK PubMed Central (United Kingdom)

We examined the bacterial aerobic nasal flora of 216 healthy volunteers to identify potential competitive interactions among different species, with special emphasis on the influence of staphylococcal...Full Text Available

2003-01-01

46

Bacterial Artificial Chromosome Mutagenesis Using Recombineering  

UK PubMed Central (United Kingdom)

Gene expression from bacterial artificial chromosome (BAC) clones has been demonstrated to facilitate physiologically relevant levels compared to viral and nonviral cDNA vectors. BACs are large enough...Full Text Available

2011-01-01

47

Association between bacterial vaginosis or chlamydial infection and miscarriage before 16 weeks' gestation: prospective community based cohort study  

UK PubMed Central (United Kingdom)

ObjectivesTo assess whether bacterial vaginosis or chlamydial infection before 10 weeks' gestation is associated with miscarriage before 16 weeks.DesignProspective...Full Text Available

2002-12-07

48

Application of tumor, bacterial and parasite susceptibility assays to study immune alterations induced by environmental chemicals  

UK PubMed Central (United Kingdom)

Model systems to study the effects of chemicals of environmental concern on bacterial and parasitic diseases as well as the immunosurveillance and destruction of transplantable tumor cells were described...Full Text Available

1982-02-01

49

ACCEPTABILITY OF A SELF-SAMPLING TECHNIQUE TO COLLECT VAGINAL SMEARS FOR GRAM STAIN DIAGNOSIS OF BACTERIAL VAGINOSIS  

UK PubMed Central (United Kingdom)

To diagnose asymptomatic bacterial vaginosis (BV), self-sampled vaginal smears were collected during a study of risk factors for preterm birth in African American women. More than 90% of those...Full Text Available

2004-01-01

50

A bacterial amber suppressor in Saccharomyces cerevisiae is selectively recognized by a bacterial aminoacyl-tRNA synthetase.  

UK PubMed Central (United Kingdom)

Little is known about the conservation of determinants for the identities of tRNAs between organisms. We showed previously that Escherichia coli tyrosine tRNA synthetase can charge the Saccharomyces...Full Text Available

1990-04-01

54

Effects of timber extraction on herb diversity in the Little Tennessee watershed.  

Science.gov (United States)

... study is to collect data in previously harvested timber stands to quantify the differences in herbaceous diversity ... ...

55

User`s guide and documentation manual for microbial transport simulator  

Energy Technology Data Exchange (ETDEWEB)

The microbial transport simulator (MTS) is a three-dimensional, three-phase, multiple-component numerical model that permits the study of the transport of microorganisms and nutrients in porous media. Microbial parameters incorporated into MTS include: Microbial growth and decay, microbial deposition, chemotaxis, diffusion, convective dispersion, tumbling, and nutrient consumption. Governing equations for microbial and nutrient transport are coupled with continuity and flow equations under conditions appropriate for a black oil reservoir. The model`s mathematical formulations and preparation procedures of data files for conducting simulations using MTS are described. A general background of microbial transport simulation is given in Section I and the governing equations, mechanisms, and numerical solutions of MTS are given in Section II. Explanations for preparing an input data file with reservoir and microbial transport data are described in Section III, and ...

1993-10-01

56

Quantitative variations in the vaginal bacterial population associated with asymptomatic infections: a real-time polymerase chain reaction study.  

Science.gov (United States)

The real-time polymerase chain reaction (PCR) quantification of several vaginal bacterial groups in healthy women and patients developing asymptomatic bacterial vaginosis (BV) and candidiasis (CA) was performed. Statistical analysis revealed that the BV condition is characterised by a great variability among subjects and that it is associated with a significant increase of Prevotella, Atopobium, Veillonella and Gardnerella vaginalis, and a drop in Lactobacillus. On the contrary, the vaginal microflora of healthy women and patients developing CA was found to be homogeneous and stable over time. PMID:18762999

2008-09-02

57

Quantitative variations in the vaginal bacterial population associated with asymptomatic infections: a real-time polymerase chain reaction study  

British Library Electronic Table of Contents (United Kingdom)

The real-time polymerase chain reaction (PCR) quantification of several vaginal bacterial groups in healthy women and patients developing asymptomatic bacterial vaginosis (BV) and candidiasis (CA) was performed. Statistical analysis revealed that the BV condition is characterised by a great variability among subjects and that it is associated with a significant increase of Prevotella, Atopobium, Veillonella and Gardnerella vaginalis, and a drop in Lactobacillus. On the contrary, the vaginal microflora of healthy women and patients developing CA was found to be homogeneous and stable over time.

2009-01-01

58

Acceleration of Emergence of Bacterial Antibiotic Resistance in Connected Microenvironments.  

Science.gov (United States)

The emergence of bacterial antibiotic resistance is a growing problem, yet the variables that influence the rate of emergence of resistance are not well understood. In a microfluidic device designed to mimic naturally occurring bacterial niches, resistance of Escherichia coli to the antibiotic ciprofloxacin developed within 10 hours. Resistance emerged with as few as 100 bacteria in the initial inoculation. Whole-genome sequencing of the resistant organisms revealed that four functional single-nucleotide polymorphisms attained fixation. Knowledge about the rapid emergence of antibiotic resistance in the heterogeneous conditions within the mammalian body may be helpful in understanding the emergence of drug resistance during cancer chemotherapy. PMID:21940899

2011-09-23

59

Small Regulatory RNA and Legionella pneumophila  

UK PubMed Central (United Kingdom)

Legionella pneumophila is a gram-negative bacterial species that is ubiquitous in almost any aqueous environment. It is the agent of Legionnaires’ disease, an acute and often...Full Text Available

61

J ji Y - NASA Technical Reports Server  

Science.gov (United States)

could be attributed either to removal of bacterial competition. (the reason for adding antibiotics before adding additional carbon and ...

62

Interaction of legionella pneumophila and helicobacter pylori with bacterial species isolated from drinking water biofilms  

UK PubMed Central (United Kingdom)

BackgroundIt is well established that Legionella pneumophila is a waterborne pathogen; by contrast, the mode of Helicobacter pylori transmission...Full Text Available

63

Expression and regulation of the NALP3 inflammasome complex in periodontal diseases  

UK PubMed Central (United Kingdom)

Periodontitis is an infectious process characterized by inflammation affecting the supporting structures of the teeth. Porphyromonas gingivalis is a major oral bacterial species implicated...Full Text Available

2009-09-01

65

Diversity of Dominant Bacterial Taxa in Activated Sludge Promotes Functional Resistance following Toxic Shock Loading  

British Library Electronic Table of Contents (United Kingdom)

Examining the relationship between biodiversity and functional stability (resistance and resilience) of activated sludge bacterial communities following disturbance is an important first step towards developing strategies for the design of robust biological wastewater treatment systems. This study investigates the relationship between functional resistance and biodiversity of dominant bacterial taxa by subjecting activated sludge samples, with different levels of biodiversity, to toxic shock loading with cupric sulfate (Cu[II]), 3,5-dichlorophenol (3,5-DCP), or 4-nitrophenol (4-NP). Respirometric batch experiments were performed to determine the functional resistance of activated sludge bacterial community to the three toxicants. Functional resistance was estimated as the 30?min IC50 or th...

2011-01-01

66

CURRICULUM VITAE  

Science.gov (United States)

... 84. Fields BS, Haupt T, Davis JP, Arduino MJ, Butler JC. Pontiac fever due to Legionella micdadei from a whirlpool spa: Possible role of bacterial endotoxin. ...

67

Bacterial flora-typing with targeted, chip-based Pyrosequencing  

UK PubMed Central (United Kingdom)

BackgroundThe metagenomic analysis of microbial communities holds the potential to improve our understanding of the role of microbes in clinical conditions. Recent, dramatic improvements...Full Text Available

68

Bacterial body plans  

UK PubMed Central (United Kingdom)

The bacterium Serratia marcescens produces a plethora of multicellular shapes of different colorations on solid substrates, allowing immediate visual detection of varieties. Such a...Full Text Available

2008-07-01

69

Antimicrobial activity and mechanism of action of Nu-3, a protonated modified nucleotide  

UK PubMed Central (United Kingdom)

Background"Nubiotics" are synthetic oligonucleotides and nucleotides with nuclease-resistant backbones, and are fully protonated for enhanced ability to be taken up by bacterial...Full Text Available

70

Alpha-toxin of Staphylococcus aureus.  

UK PubMed Central (United Kingdom)

Alpha-toxin, the major cytotoxic agent elaborated by Staphylococcus aureus, was the first bacterial exotoxin to be identified as a pore former. The protein is secreted as a single-chain, water-soluble...Full Text Available

1991-12-01

71

9902631 - Lysozyme - NASA  

Science.gov (United States)

Protein isolated from hen egg-white and functions as a bacteriostatic enzyme by degrading bacterial cell walls. First enzyme ever characterized by protein ...

72

Newer systems for bacterial resistances to toxic heavy metals.  

UK PubMed Central (United Kingdom)

Bacterial plasmids contain specific genes for resistances to toxic heavy metal ions including Ag+, AsO2-, AsO4(3-), Cd2+, Co2+, CrO4(2-), Cu2+, Hg2+, Ni2+, Pb2+, Sb3+, and Zn2+. Recent progress with...Full Text Available

1994-09-01

73

Nature of plant stimulators in the production of Acetobacter xylinum ({open_quotes}Tea fungas{close_quotes}) biofilm used in skin therapy  

Energy Technology Data Exchange (ETDEWEB)

Caffeine and related xanthines were identified as potent stimulators for the bacterial cellulose production in A. xylinum. These compounds are present in several plants whose infusions are useful as culture-medium supplements for this acetobacterium. The proposed target for these native purine-like inhibitory substances is the novel diguanyl nucleotide phosphodiesterase(s) that participates in the bacterial cellulogenic complex.

1991-12-31

74

Crystal Structure of the Mycobacterium fortuitum Class A ?-Lactamase: Structural Basis for Broad Substrate Specificity  

UK PubMed Central (United Kingdom)

β-Lactamases are the main cause of bacterial resistance to penicillins and cephalosporins. Class A β-lactamases, the largest group of β-lactamases, have been found in many bacterial...Full Text Available

2006-07-01

75

Introduction of microbial nutrients in a nuclear fuel waste disposal vault as a result of excavation and operation activities  

International Nuclear Information System (INIS)

A nuclear fuel waste disposal vault would not likely be a sterile environment. Bacterial activity would be expected in those areas of the vault conducive to bacterial life, i.e., where effects of heat, moisture content, radiation and compaction would not prevent or severely restrict bacterial life and where suitable and sufficient nutrients would be present. An inventory of bacterial nutrients that would be emplaced 'intentionally' with vault materials (fuel waste, waste containers, buffer and backfill materials) has been made previously. This report assesses bacterial nutrients that would be added 'inadvertently' to a vault in the form of residues of materials used to excavate and operate a vault. Measurements of blasting material residues in the various water supplies, excavated broken rock (muck) and in cores drilled in old and new tunnel walls were made at AECL's Underground ...

1987-08-27

76

Bacterial Pili exploit integrin machinery to promote immune activation and efficient blood-brain barrier penetration.  

Science.gov (United States)

Group B Streptococcus (GBS) is the leading cause of meningitis in newborn infants. Bacterial cell surface appendages, known as pili, have been recently described in streptococcal pathogens, including GBS. The pilus tip adhesin, PilA, contributes to GBS adherence to blood-brain barrier (BBB) endothelium; however, the host receptor and the contribution of PilA in central nervous system (CNS) disease pathogenesis are unknown. Here we show that PilA binds collagen, which promotes GBS interaction with the ?(2)?(1) integrin resulting in activation of host chemokine expression and neutrophil recruitment during infection. Mice infected with the PilA-deficient mutant exhibit delayed mortality, a decrease in neutrophil infiltration and bacterial CNS dissemination. We find that PilA-mediated virulence is dependent on neutrophil influx as neutrophil depletion results in a decrease in BBB permeability and GBS-BBB penetration. Our results suggest that the ...

2011-09-06

77

Nature and distribution of mucosal lesions associated with enteropathogenic and enterohemorrhagic Escherichia coli in piglets and the role of plasmid-mediated factors.  

Science.gov (United States)

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 strains belonging to five EPEC serogroups, O55, O142, O26, ...

1989-04-01

78

Effect of Lactobacillus supplementation with and without arginine on liver damage and bacterial translocation in an acute liver injury model in the rat.  

Science.gov (United States)

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 weight), and samples were collected after 24 and 48 hours. ...

1997-03-01

79

Quantifying Risk Factors for Human Brucellosis in Rural Northern Tanzania  

UK PubMed Central (United Kingdom)

BackgroundBrucellosis is a zoonosis of veterinary, public health and economic significance in most developing countries. Human brucellosis is a severely debilitating disease that...Full Text Available

80

Particle-Gas Dynamics and Primary Accretion - Space Science and ...  

Science.gov (United States)

the revealed stage of T Tauri star evolution, is only a mere shadow of its former self. Once primary accretion starts, one has the (poorly quantified) ...

81

In vivo range of motion of the lumbar spinous processes  

UK PubMed Central (United Kingdom)

The study design included an in vivo laboratory study. The objective of the study is to quantify the kinematics of the lumbar spinous processes in asymptomatic patients during un-restricted functional...Full Text Available

2009-09-01

82

A Caution Against Interpreting and Quantifying Oyster Habitat Loss from Historical Surveys  

Science.gov (United States)

... surveys, and increasing interest in both developing an oyster aquaculture industry and scaling up restoration efforts by federal, ... ...

83

The mammalian neuroendocrine hormone norepinephrine supplies iron for bacterial growth in the presence of transferrin or lactoferrin.  

Science.gov (United States)

Norepinephrine stimulates the growth of a range of bacterial species in nutritionally poor SAPI minimal salts medium containing 30% serum. Addition of size-fractionated serum components to SAPI medium indicated that transferrin was required for norepinephrine stimulation of growth of Escherichia coli. Since bacteriostasis by serum is primarily due to the iron-withholding capacity of transferrin, we considered the possibility that norepinephrine can overcome this effect by supplying transferrin-bound iron for growth. Incubation with concentrations of norepinephrine that stimulated bacterial growth in serum-SAPI medium resulted in loss of bound iron from iron-saturated transferrin, as indicated by the appearance of monoferric and apo- isoforms upon electrophoresis in denaturing gels. Norepinephrine also caused the loss of iron from lactoferrin. The pharmacologically inactive metabolite norepinephrine 3-O-sulfate, by contrast, did not result in ...

2000-11-01

84

Thermokinetic investigation of effects of carbon source on petroleum bacterial growth  

Energy Technology Data Exchange (ETDEWEB)

The growth power-time curves of a strain of petroleum bacteria, B-2, in various kinds of cultures containing different kinds of carbon sources, glucose, n-tetradecane, n-hexadecane and n-octadecane, and different kinds of microemulsions have been determined by using a 2277 Thermal Activity Monitor. The curves showed a single peak for cultures containing a single carbon source, glucose, and two peaks for cultures containing two kinds of carbon sources, glucose and one of the n-alkanes. The first peak indicated that bacteria grew by consuming glucose and the second peak indicated that bacteria grew by consuming n-alkane. The curves were complex when the bacterium grows in a microemulsion culture. According to a kinetic equation of bacterial growth under limited conditions, the rate constants of bacterial growth were obtained. The results showed that the microemulsion culture was more appropriate to bacteria to grow on n-alkanes.

2002-02-07

85

The utilization of polysaccharides by heterotrophic bacterioplankton in the Bay of Biscay (North Atlantic Ocean)  

British Library Electronic Table of Contents (United Kingdom)

This study investigates the turnover of polysaccharides by heterotrophic bacterioplankton in the northern Bay of Biscay, a productive marine system on the continental margin of the temperate Atlantic Ocean. Bacterial biomass production (BBP) near the surface ranged from 0.5 to 25.7 nmol C L?1 h?1 during small phytoplankton blooms in May and June that occurred after the main spring bloom. A direct relationship between BBP and total polysaccharides strongly suggests the dependence of bacterial growth on the availability of semi-labile organic matter. Concentrations of combined glucose as well as rate constants of extracellular glucosidase activity and glucose uptake were determined to estimate the actual carbon fluxes from bacterial polysaccharide turnover. Results reveal that ...

2011-01-01

86

Bacterial vaginosis and other asymptomatic vaginal infections in pregnancy.  

Science.gov (United States)

Preterm birth is a common cause of neonatal morbidity and mortality. Many asymptomatic genital infections have been associated with preterm birth, but attempts to determine a causal relationship between specific infections and preterm birth have been disappointing. Treatment trials of specific infections have generally failed to show a positive effect, and in some trials have shown a deleterious effect. Although there is a strong association between the presence of bacterial vaginosis and Trichomonas vaginalis in pregnancy and preterm birth, randomized treatment trials have failed to show a benefit of treatment of these organisms. Treatment of asymptomatic bacterial vaginosis or T. vaginalis to prevent preterm birth is not warranted. PMID:12112946

2001-08-01

87

Bacterial adhesion reduction on a biocompatible Si^+ ion implanted austenitic stainless steel  

British Library Electronic Table of Contents (United Kingdom)

The colonization of an implant surface by bacteria is an extremely important medical problem, which often leads to the failure of medical devices. Modern surface modification techniques, such as ion implantation, can confer to the surfaces very different properties from those of the bulk underlying material. In this work, austenitic stainless steel 316 LVM has been superficially modified by Si^+ ion implantation. The effect of surface modification on the biocompatibility and bacterial adhesion to 316 LVM stainless steel has been investigated. To this aim, human mesenchymal stem cells (hMSCs), as precursor of osteoblastic cells, and bacterial strains relevant in infections related to orthopedic implants, i.e., Staphylococcus aureus and Staphylococcus epidermidis, have been assayed. For the ...

2011-01-01

88

Allelochemicals produced by Caribbean macroalgae and cyanobacteria have species-specific effects on reef coral microorganisms  

British Library Electronic Table of Contents (United Kingdom)

Coral populations have precipitously declined on Caribbean reefs while algal abundance has increased, leading to enhanced competitive damage to corals, which likely is mediated by the potent allelochemicals produced by both macroalgae and benthic cyanobacteria. Allelochemicals may affect the composition and abundance of coral-associated microorganisms that control host responses and adaptations to environmental change, including susceptibility to bacterial diseases. Here, we demonstrate that extracts of six Caribbean macroalgae and two benthic cyanobacteria have both inhibitory and stimulatory effects on bacterial taxa cultured from the surfaces of Caribbean corals, macroalgae, and corals exposed to macroalgal extracts. The growth of 54 bacterial isolates was monitored in the presence of l...

2011-01-01

89

Worlds within worlds: evolution of the vertebrate gut microbiota  

UK PubMed Central (United Kingdom)

Here we use published 16S rRNA gene sequences to compare the bacterial assemblages associated with humans, other mammals, other metazoa, and free-living microbial communities spanning a range...Full Text Available

2008-10-01

90

Transcriptome Profiling of a Toxic Dinoflagellate Reveals a Gene-Rich Protist and a Potential Impact on Gene Expression Due to Bacterial Presence  

UK PubMed Central (United Kingdom)

BackgroundDinoflagellates are unicellular, often photosynthetic protists that play a major role in the dynamics of the Earth's oceans and climate. Sequencing of dinoflagellate nuclear...Full Text Available

91

The inhibition of staphylococcus epidermidis biofilm formation by vancomycin-modified titanium alloy and implications for the treatment of periprosthetic infection  

UK PubMed Central (United Kingdom)

Peri-prosthetic infections are notoriously difficult to treat as the biomaterial implant is ideal for bacterial adhesion and biofilm formation, resulting in decreased antibiotic sensitivity....Full Text Available

2008-12-01

92

The antimicrobial resistance patterns and associated determinants in Streptococcus suis isolated from humans in southern Vietnam, 1997-2008  

UK PubMed Central (United Kingdom)

BackgroundStreptococcus suis is an emerging zoonotic pathogen and is the leading cause of bacterial meningitis in adults in Vietnam. Systematic data on the antimicrobial...Full Text Available

93

The Subtilisin-Like Protease AprV2 Is Required for Virulence and Uses a Novel Disulphide-Tethered Exosite to Bind Substrates  

UK PubMed Central (United Kingdom)

Many bacterial pathogens produce extracellular proteases that degrade the extracellular matrix of the host and therefore are involved in disease pathogenesis. Dichelobacter nodosus...Full Text Available

2010-11-01

94

Single-Step Production of a Recyclable Nanobiocatalyst for Organophosphate Pesticides Biodegradation Using Functionalized Bacterial Magnetosomes  

UK PubMed Central (United Kingdom)

Enzymes are versatile catalysts in laboratories and on an industrial scale; improving their immobilization would be beneficial to broadening their applicability and ensuring their (re)use. Lipid-coated...Full Text Available

95

Seasonal and Spatial Variability of Bacterial and Archaeal Assemblages in the Coastal Waters near Anvers Island, Antarctica  

UK PubMed Central (United Kingdom)

A previous report of high levels of members of the domain Archaea in Antarctic coastal waters prompted us to investigate the ecology of Antarctic planktonic prokaryotes. rRNA hybridization...Full Text Available

1998-07-01

96

Relationship between Hydroxy Fatty Acids and Prostaglandin E2 in Gingival Tissue  

UK PubMed Central (United Kingdom)

Bacterial hydroxy fatty acids and alpha-hydroxy fatty acids have been demonstrated in complex lipid extracts of subgingival plaque and gingival tissue. However, little is known about the relationship...Full Text Available

1998-12-01

97

Pseudomonas aeruginosa selective adherence to and entry into human endothelial cells.  

UK PubMed Central (United Kingdom)

The pathogenesis of Pseudomonas aeruginosa disseminated infections depends on bacterial interaction with blood vessels. We have hypothesized that in order to traverse the endothelial barrier, bacteria...Full Text Available

1994-12-01

98

Plant and algal interference in bacterial beta-D-galactosidase and beta-D-glucuronidase assays.  

UK PubMed Central (United Kingdom)

Several commonly occurring freshwater and marine plants and algae were screened for beta-D-galactosidase and beta-D-glucuronidase activities by using a 60-min enzyme assay based on the hydrolysis by...Full Text Available

1994-11-01

99

Parallel Evolution of a Type IV Secretion System in Radiating Lineages of the Host-Restricted Bacterial Pathogen Bartonella  

UK PubMed Central (United Kingdom)

Adaptive radiation is the rapid origination of multiple species from a single ancestor as the result of concurrent adaptation to disparate environments. This fundamental evolutionary process is considered...Full Text Available

2011-02-01

100

Overexpression of bacterial ethylene-forming enzyme gene in Trichoderma reesei enhanced the production of ethylene  

UK PubMed Central (United Kingdom)

In order to efficiently utilize natural cellulose materials to produce ethylene, three expression vectors containing the ethylene-forming enzyme (efe) gene from Pseudomonas...Full Text Available

101

OmpA of Uropathogenic Escherichia coli Promotes Postinvasion Pathogenesis of Cystitis?  

UK PubMed Central (United Kingdom)

Type 1 pilus directs bladder epithelial binding and invasion by uropathogenic Escherichia coli (UPEC) in the initial stage of cystitis, but the bacterial determinants of postinvasion...Full Text Available

2009-12-01

102

Occurrence and distribution of bacterial indicators and pathogens in canal communities along the Texas coast.  

UK PubMed Central (United Kingdom)

Increased construction of residential canal communities along the southern coastline of the United States has led to a concern about their impact on water quality. Pollution of such dead-end canals...Full Text Available

1977-08-01

103

Nuclear receptor ERR? and coactivator PGC-1? are effectors of IFN-?-induced host defense  

UK PubMed Central (United Kingdom)

Macrophage activation by the proinflammatory cytokine interferon-γ (IFN-γ) is a critical component of the host innate response to bacterial pathogenesis. However, the precise nature...Full Text Available

2007-08-01

104

Molecular Evidence of Bartonella Infection in Domestic Dogs from Algeria, North Africa, by Polymerase Chain Reaction (PCR)  

UK PubMed Central (United Kingdom)

Bartonella species are being recognized as important bacterial human and canine pathogens, and are associated with multiple arthropod vectors. Bartonella DNA extracted...Full Text Available

2010-08-05

105

Modification of Spatial Distribution of 2,4-Dichlorophenoxyacetic Acid Degrader Microhabitats during Growth in Soil Columns  

UK PubMed Central (United Kingdom)

Bacterial processes in soil, including biodegradation, require contact between bacteria and substrates. Knowledge of the three-dimensional spatial distribution of bacteria at the microscale is necessary...Full Text Available

2004-05-01

106

Measurement of the Water Potential of Stored Potato Tubers 1  

UK PubMed Central (United Kingdom)

A method of measuring the water potential of stored potato tubers (Solanum tuberosum L.) was needed to investigate the relationship of bacterial soft rot in tubers to water potential....Full Text Available

1985-11-01

107

LOUSE-BORNE BACTERIAL PATHOGENS IN LICE (PHTHIRAPTERA) OF RODENTS AND CATTLE FROM EGYPT  

Science.gov (United States)

... were erroneous. The oriental rat flea, Xenopsylla cheopis Rothschild, is considered to be the primary vector of ... laboratory and production of Weigl's exanthematous typhus vaccine. In Maintenance of hum...

108

Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction  

UK PubMed Central (United Kingdom)

BackgroundThe maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters...Full Text Available

109

Insights into Genome Plasticity and Pathogenicity of the Plant Pathogenic Bacterium Xanthomonas campestris pv. vesicatoria Revealed by the Complete Genome Sequence  

UK PubMed Central (United Kingdom)

The gram-negative plant-pathogenic bacterium Xanthomonas campestris pv. vesicatoria is the causative agent of bacterial spot disease in pepper and tomato plants, which leads to economically...Full Text Available

2005-11-01

110

Induction of nonspecific tolerance to endotoxins reduces the alveolar bone resorption in ligature-treated rats.  

UK PubMed Central (United Kingdom)

Previous experimental data from various laboratories indicate that endotoxin of gram-negative oral microorganisms might be one of the most important bacterial products involved in bone resorption during...Full Text Available

1983-02-01

111

In vivo expression and mitochondrial targeting of yeast apoiso-1-cytochrome c fusion proteins.  

UK PubMed Central (United Kingdom)

To define the import pathway for apoiso-1-cytochrome c in vivo, the coding region for bacterial chloramphenicol acetyltransferase (CAT) or yeast copper metallothionein (CuMT) was fused to the carboxy...Full Text Available

1990-11-01

112

Identification of plasmid and Bacillus subtilis chromosomal recombination sites used for pE194 integration.  

UK PubMed Central (United Kingdom)

The plasmid pE194 (3.7 kilobases) is capable of integrating into the genome of the bacterial host Bacillus subtilis in the absence of the major homology-dependent RecE recombination system. Multiple...Full Text Available

1989-05-01

114

Heavy metals alter the electrokinetic properties of bacteria, yeasts, and clay minerals.  

UK PubMed Central (United Kingdom)

The electrokinetic patterns of four bacterial species (Bacillus subtilis, Bacillus megaterium, Pseudomonas aeruginosa, and Agrobacterium radiobacter), two yeasts (Saccharomyces cerevisiae and Candida...Full Text Available

1992-05-01

115

Gingival crevicular fluid levels of clindamycin compared with its minimal inhibitory concentrations for periodontal bacteria.  

UK PubMed Central (United Kingdom)

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

1981-05-01

116

Genomic Evidence for the Evolution of Streptococcus equi: Host Restriction, Increased Virulence, and Genetic Exchange with Human Pathogens  

UK PubMed Central (United Kingdom)

The continued evolution of bacterial pathogens has major implications for both human and animal disease, but the exchange of genetic material between host-restricted pathogens is rarely considered....Full Text Available

2009-03-01

117

Genome-Wide Transcriptional Response of Chemostat-Cultured Escherichia coli to Zinc  

UK PubMed Central (United Kingdom)

Zinc is an essential trace metal ion for growth, but an excess of Zn is toxic and microorganisms express diverse resistance mechanisms. To understand global bacterial responses to excess Zn, we conducted...Full Text Available

2005-02-01

118

Genetic Heterogeneity in Severe Congenital Neutropenia: How Many Aberrant Pathways Can Kill a Neutrophil?  

UK PubMed Central (United Kingdom)

Purpose of reviewSevere congenital neutropenia (SCN) is a primary immunodeficiency in which lack of neutrophils causes inadequate innate immune host response to bacterial...Full Text Available

2007-12-01

119

Genetic Evidence for Inhibition of Bacterial Division Protein FtsZ by Berberine  

UK PubMed Central (United Kingdom)

BackgroundBerberine is a plant alkaloid that is widely used as an anti-infective in traditional medicine. Escherichia coli exposed to berberine form filaments, suggesting...Full Text Available

120

Factors Affecting Daughter Cells' Arrangement during the Early Bacterial Divisions  

UK PubMed Central (United Kingdom)

On agar plates, daughter cells of Escherichia coli mutually slide and align side-by-side in parallel during the first round of binary fission. This phenomenon has been previously attributed...Full Text Available

121

Evaluating the Involvement of Alternative Sigma Factors SigF and SigG in Clostridium perfringens Sporulation and Enterotoxin Synthesis?  

UK PubMed Central (United Kingdom)

Clostridium perfringens type A food poisoning is the second most commonly identified bacterial food-borne illness. Sporulation contributes to this disease in two ways: (i) most food-poisoning...Full Text Available

2010-10-01

122

Endometrial biopsy in Holstein-Friesian dairy cows. III. Bacteriological analysis and correlations with histological findings.  

UK PubMed Central (United Kingdom)

This study examines the results of bacterial culture from 159 endometrial biopsy samples from 97 commercial dairy cows and correlations between bacteriological and histological findings. Bacteria were...Full Text Available

1991-04-01

123

Endogenous Nitric Oxide Protects Bacteria Against a Wide Spectrum of Antibiotics  

UK PubMed Central (United Kingdom)

Bacterial nitric oxide synthases (bNOS) are present in many Gram-positive species and have been demonstrated to synthesize NO from arginine in vitro and in vivo. However, the physiological role...Full Text Available

2009-09-11

124

Effect of Wastewater Treatment Plant Effluent on Microbial Function and Community Structure in the Sediment of a Freshwater Stream with Variable Seasonal Flow?  

UK PubMed Central (United Kingdom)

We investigated the effects of wastewater treatment plant (WWTP) discharge on the ecology of bacterial communities in the sediment of a small, low-gradient stream in South Australia. The quantification...Full Text Available

2008-05-01

125

Effect of Feeding Cows Genetically Modified Maize on the Bacterial Community in the Bovine Rumen?  

UK PubMed Central (United Kingdom)

Rumen-cannulated cows (n = 4) were fed successively silage made from either conventional or genetically modified (GM) maize. Results revealed no effects of GM maize on the dynamics...Full Text Available

2007-12-01

126

Distribution Frequency of Pathogenic Bacteria Isolated from Cutaneus Leishmaniasis Lesions  

UK PubMed Central (United Kingdom)

Cutaneous leishmaniasis (CL) is a parasitic disease characterized by single or multiple ulcerations. Secondary bacterial infections are one of the complications that can increase the tissue destruction...Full Text Available

2008-09-01

127

Distinct signatures of diversifying selection revealed by genome analysis of respiratory tract and invasive bacterial populations  

UK PubMed Central (United Kingdom)

Many pathogens colonize different anatomical sites, but the selective pressures contributing to survival in the diverse niches are poorly understood. Group A Streptococcus (GAS) is...Full Text Available

2011-03-22

128

Display of Recombinant Proteins on Bacillus subtilis Spores, Using a Coat-Associated Enzyme as the Carrier?  

UK PubMed Central (United Kingdom)

The display of proteins such as feed enzymes at the surface of bacterial spore systems has a great potential use for animal feed. Feed enzymes increase the digestibility of nutrients, leading to greater...Full Text Available

2010-09-01

129

Detection of Streptococcus mutans Genomic DNA in Human DNA Samples Extracted from Saliva and Blood  

UK PubMed Central (United Kingdom)

Caries is a multifactorial disease, and studies aiming to unravel the factors modulating its etiology must consider all known predisposing factors. One major factor is bacterial colonization,...Full Text Available

2011-01-01

130

Detection of Atopobium vaginae in Postmenopausal Women by Cultivation-Independent Methods Warrants Further Investigation  

UK PubMed Central (United Kingdom)

We sequenced 16S rRNA genes from the vaginal swab contents of a postmenopausal woman with asymptomatic bacterial vaginosis (BV). Sequences from Atopobium vaginae were the most commonly...Full Text Available

2004-04-01

131

Delineating Bacteriostatic and Bactericidal Targets in Mycobacteria Using IPTG Inducible Antisense Expression  

UK PubMed Central (United Kingdom)

In order to identify novel high value antibacterial targets it is desirable to delineate whether the inactivation of the target enzyme will lead to bacterial death or stasis. This knowledge is particularly...Full Text Available

132

Biotransformation of Explosives by the Old Yellow Enzyme Family of Flavoproteins  

UK PubMed Central (United Kingdom)

Several independent studies of bacterial degradation of nitrate ester explosives have demonstrated the involvement of flavin-dependent oxidoreductases related to the old yellow enzyme (OYE) of yeast....Full Text Available

2004-06-01

133

Biological processing and interactions with coal: Summary of activities for the period January 1, 1988--March 31, 1988  

Science.gov (United States)

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)

1988-01-01

134

Binary Bacterial Toxins: Biochemistry, Biology, and Applications of Common Clostridium and Bacillus Proteins  

UK PubMed Central (United Kingdom)

Certain pathogenic species of Bacillus and Clostridium have developed unique methods for intoxicating cells that employ the classic enzymatic “A-B” paradigm for protein toxins. The binary...Full Text Available

2004-09-01

135

Bacterial response to siderophore and quorum-sensing chemical signals in the seawater microbial community  

UK PubMed Central (United Kingdom)

BackgroundOceans are iron-deficient and nutrient-poor environments. These conditions impart limitations on our understanding of and our ability to identify microorganisms from the...Full Text Available

136

Bacterial lipopolysaccharide induces an endocrine switch from prostaglandin F2? to prostaglandin E2 in bovine endometrium  

UK PubMed Central (United Kingdom)

Escherichia coli infection of the endometrium causes uterine disease after parturition and is associated with prolonged luteal phases of the ovarian cycle in cattle. Termination...Full Text Available

2009-04-01

137

Bacterial infections in suspected cutaneous leishmaniasis lesions.  

UK PubMed Central (United Kingdom)

In Iran, microscopic examination of skin scrapings from 2202 individuals with clinically diagnosed cutaneous leishmaniasis (CL) lesions revealed the presence of amastigotes in 1123 cases (51.0%). Bacteriological...Full Text Available

1990-01-01

138

Bacterial indicators of risk of diarrhoeal disease from drinking-water in the Philippines.  

UK PubMed Central (United Kingdom)

Inadequate measures of water quality have been used in many studies of the health effects associated with water supplies in developing countries. The present 1-year epidemiological-microbiological study...Full Text Available

1991-01-01

139

Bacterial glycolipids and analogs as antigens for CD1d-restricted NKT cells  

UK PubMed Central (United Kingdom)

The CD1 family of proteins binds self and foreign glycolipids for presentation to CD1-restricted T cells. To identify previously uncharacterized active CD1 ligands, especially those of microbial origin,...Full Text Available

2005-02-01

140

Association of Nasophyaryngeal Bacterial Colonization during Upper Respiratory Tract Infection and the Development of Acute Otitis Media  

UK PubMed Central (United Kingdom)

Acute Otitis Media occurs mostly after upper respiratory tract infection; the causative bacteria are those colonized in the nasopharynx. We studied 709 URI episodes and found that children with...Full Text Available

2008-02-15

141

Association between skin diseases and severe bacterial infections in children: case-control study  

UK PubMed Central (United Kingdom)

BackgroundSepsis or bacteraemia, however rare, is a significant cause of high mortality and serious complications in children. In previous studies skin disease or skin infections...Full Text Available

142

Antimicrobial susceptibilities of bacteria associated with periodontal disease.  

UK PubMed Central (United Kingdom)

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

1983-03-01

143

Analysis of the Sulfate-Reducing Bacterial and Methanogenic Archaeal Populations in Contrasting Antarctic Sediments  

UK PubMed Central (United Kingdom)

The distribution and activity of communities of sulfate-reducing bacteria (SRB) and methanogenic archaea in two contrasting Antarctic sediments were investigated. Methanogenesis dominated in freshwater...Full Text Available

2003-06-01

144

Allosteric regulation of glycerol kinase by enzyme IIIglc of the phosphotransferase system in Escherichia coli and Salmonella typhimurium.  

UK PubMed Central (United Kingdom)

The mechanism by which enzyme IIIglc of the bacterial phosphotransferase system regulates the activity of crystalline glycerol kinase from Escherichia coli has been studied, and the inhibitory effects...Full Text Available

1985-05-01

145

Adrenaline modulates the global transcriptional profile of Salmonella revealing a role in the antimicrobial peptide and oxidative stress resistance responses  

UK PubMed Central (United Kingdom)

BackgroundThe successful interaction of bacterial pathogens with host tissues requires the sensing of specific chemical and physical cues. The human gut contains a huge number of...Full Text Available

146

Actinobacillus actinomycetemcomitans Lipopolysaccharide-Mediated Experimental Bone Loss Model for Aggressive Periodontitis  

UK PubMed Central (United Kingdom)

BackgroundBacterial constituents, such as Gram-negative derived lipopolysaccharide (LPS), can initiate inflammatory bone loss through induction of host-derived inflammatory...Full Text Available

2007-03-01

147

Acetic Acid Bacterial Biota of the Pink Sugar Cane Mealybug, Saccharococcus sacchari, and Its Environs  

UK PubMed Central (United Kingdom)

Saccharococcus sacchari is the primary colonizer of the developing “sterile” tissue between the leaf sheath and stem of sugar cane. The honeydew secreted by the mealybugs...Full Text Available

1990-03-01

148

ADP-Glucose Pyrophosphorylase, a Regulatory Enzyme for Bacterial Glycogen Synthesis  

UK PubMed Central (United Kingdom)

The accumulation of α-1,4-polyglucans is an important strategy to cope with transient starvation conditions in the environment. In bacteria and plants, the synthesis of glycogen and starch occurs...Full Text Available

2003-06-01

149

A report of clinical trial conducted on Toto ointment and soap products.  

UK PubMed Central (United Kingdom)

OBJECTIVE: The efficacy of Toto ointment and soap on common skin disorders was tested. METHODOLOGY: A cohort of Nigerians with common skin conditions such as fungal and bacterial skin infections, scabies,...Full Text Available

2003-01-01

150

A Marker-Dense Physical Map of the Bradyrhizobium japonicum Genome  

UK PubMed Central (United Kingdom)

Bacterial artificial chromosome (BAC) clones are effective mapping and sequencing reagents for use with a wide variety of small and large genomes. This report describes the development of a physical...Full Text Available

2001-08-01

151

A Coxiella burnetti repeated DNA element resembling a bacterial insertion sequence.  

UK PubMed Central (United Kingdom)

A DNA fragment located on the 3' side of the Coxiella burnetii htpAB operon was determined by Southern blotting to exist in approximately 19 copies in the Nine Mile I genome. The DNA sequences of this...Full Text Available

1992-09-01

152

Effect of tetracycline hydrochloride treatment on the critical thermal maximum of common shiners  

Energy Technology Data Exchange (ETDEWEB)

The transfer of fish from field to laboratory facilities or their propagation in closed or restricted systems frequently results in bacterial infection and ultimately large-scale mortality. In attemps to alleviate this problem, we have added tetracycline hydrochloride to the water prophylactically (pretreating tanks before wild fish were added) and therapeutically (treating tanks after bacterial outbreaks were detected.) In the present study, we examined the effect of tetracyline hydrochloride on the critical thermal maximum (CTM) of the common shiner (Notropis cornutus).

1980-01-01

153

Safety calculation for an underground repository for radioactive waste: the first objective of the alliances calculation software platform  

International Nuclear Information System (INIS)

The aim of the safety calculation is to quantify through numerical modelling the radiological impact (molar flow, human dose) of a potential repository for radioactive waste on the Meuse/Haute Marne site at Bure. A selection process is underway for safety scenarios and their phenomenological and numerical conceptual models upstream from the safety calculation. This involves defining and quantifying the geometric and dimensional representations of the repository for each scenario plus the physical, mathematical and numerical models that reflect its behaviour and the uncertainties associated with all the parameters required to quantify the impact. A summary will be given of these various aspects. The numerical simulations are then performed on the Alliances platform which integrates the various computer codes required for the physical representation of the system. (authors)

2005-03-14

154

Efficient methodologies for sensitive HIV-1 RNA quantitation from plasma and vaginal secretions  

British Library Electronic Table of Contents (United Kingdom)

Background: Quantifying HIV levels in mucosal secretions is essential to study compartmentalized expression of HIV and facilitate development of intervention strategies to prevent disease progression and transmission. Objectives: To develop a sensitive, reliable, and cost-effective technique to quantify HIV from blood and vaginal secretions that is compatible with efficient implementation in clinical research environments. Study design: A sensitive, reliable, internally-controlled real-time reverse transcriptase (RT) PCR assay, which uses the HIV-1 pol gene as a target (Hpol assay) was developed to quantify HIV levels in plasma and genital secretions, and compared to the widely used Roche Amplicor(TM) HIV-1 Monitor assay. In addition, a simplified method of sample collection and processing...

2009-01-01

155

Characterization and uncertainty analysis of VOCs emissions from industrial wastewater treatment plants  

British Library Electronic Table of Contents (United Kingdom)

Air toxics from the industrial wastewater treatment plants (IWTPs) impose serious health concerns on its surrounding residential neighborhoods. To address such health concerns, one of the key challenges is to quantify the air emissions from the IWTPs. The objective here is to characterize the air emissions from the IWTPs and quantify its associated uncertainty. An IWTP receiving the wastewaters from an airplane maintenance facility is used for illustration with focus on the quantification of air emissions for benzyl alcohol, phenol, methylene chloride, 2-butanone, and acetone. Two general fate models, i.e., WATER9 and TOXCHEM+V3.0 were used to model the IWTP and quantify the air emissions. Monte Carlo and Bootstrap simulation were used for uncertainty analysis. On average, air emissions fr...

2010-01-01

156

Expression of bacterial luciferase in eukaryotic cells  

International Nuclear Information System (INIS)

Expression of Bacterial luciferase enzyme (lux) in mammalian cells would be a powerful bioreporter protein system for in vivo imaging because eukaryotic luciferases need expensive substrates. However, only a few efforts have been made to express bacterial luciferase enzyme in mammalian cells. As the result of this, we attempted to construct bicistronic vector including two bacterial luciferase genes (LuxA and LuxB) for assessing the potential to be visualized in vitro or in vivo by optical imaging system after transfection to mammalian cells. We designed and synthesized luxA and luxB genes from Photorhabdus Luminescens. To co-express both luxA and luxB genes from a single promoter, we cloned as a bicistronic transcript fused with an internal ribosomal entry site (IRES). This bicistronic transcript was transfected by Superfect to HEK 293T cell line. We also transfected lux A and lux B vector to HEK 293T cells separately. To ...

2005-11-18

157

Xylem Embolism in Response to Freeze-Thaw Cycles and Water Stress in Ring-Porous, Diffuse-Porous, and Conifer Species 1  

UK PubMed Central (United Kingdom)

Vulnerability to xylem embolism by freeze-thaw cycles and water stress was quantified in ring-porous (Quercus gambelii Nutt.), diffuse-porous (Populus tremuloides Michx.,...Full Text Available

1992-10-01

158

Variability In Motor Learning: Relocating, Channeling and Reducing Noise  

UK PubMed Central (United Kingdom)

Variability in motor performance decreases with practice but is never entirely eliminated, due in part to inherent motor noise. The present study develops a method that quantifies how performers...Full Text Available

2009-02-01

159

Transcription induces strand-specific mutations at the 5? end of human genes  

UK PubMed Central (United Kingdom)

A regional analysis of nucleotide substitution rates along human genes and their flanking regions allows us to quantify the effect of mutational mechanisms associated with transcription in germ line...Full Text Available

2008-08-01

160

Three-Dimensional Traction Force Microscopy: A New Tool for Quantifying Cell-Matrix Interactions  

UK PubMed Central (United Kingdom)

The interactions between biochemical processes and mechanical signaling play important roles during various cellular processes such as wound healing, embryogenesis, metastasis, and cell migration. While...Full Text Available

161

The effect of maternal anthropometric characteristics and social factors on gestational age and birth weight in Sudanese newborn infants  

UK PubMed Central (United Kingdom)

BackgroundIn Africa low birth weight (LBW) (<2500 g), is the strongest determinant of infant morbidity and mortality. The aim of this study was to quantify the effect of...Full Text Available

162

The Trade-Off between Costs and Outcomes: The Case of Acute Myocardial Infarction  

UK PubMed Central (United Kingdom)

ObjectiveTo investigate and to quantify the relationship between hospital costs and health outcomes for patients with acute myocardial infarction (AMI) in Veterans Health Administration...Full Text Available

2010-12-01

163

Quantifying the accuracy of automated structure segmentation in 4D CT images using a deformable image registration algorithm  

UK PubMed Central (United Kingdom)

Four-dimensional (4D) radiotherapy is the explicit inclusion of the temporal changes in anatomy during the imaging, planning, and delivery of radiotherapy. One key component of 4D radiotherapy planning...Full Text Available

2008-04-01

164

Quantifiable Biomarkers of Normal Aging in the Japanese Medaka Fish (Oryzias latipes)  

UK PubMed Central (United Kingdom)

BackgroundSmall laboratory fish share many anatomical and histological characteristics with other vertebrates, yet can be maintained in large numbers at low cost for lifetime studies....Full Text Available

165

Proteome-wide Anti-HCV and Anti-HIV Antibody Profiling for Predicting and Monitoring Response to HCV Treatment in HIV Co-infected Patients  

UK PubMed Central (United Kingdom)

We quantified antibody responses to the HCV proteome that are associated with sustained virologic response (SVR) in HIV/HCV co-infected patients treated with pegylated interferon and ribavirin....Full Text Available

2010-09-15

166

Prevalence and trends of selected urologic conditions for VA healthcare users  

UK PubMed Central (United Kingdom)

BackgroundConducted as part of the Urologic Diseases in America project whose aim was to quantify the burden of urologic diseases on the American public, this study focuses on Veterans...Full Text Available

167

Predictive Value of Kushida Index and Acoustic Pharyngometry for the Evaluation of Upper Airway in Subjects With or Without Obstructive Sleep Apnea  

UK PubMed Central (United Kingdom)

Acoustic pharyngometry is a relatively new noninvasive method that quantifies geometrically complexed pharyngeal dimensions. Our study aimed to investigate the predictability and usefulness of acoustic...Full Text Available

2004-10-01

168

Predicting Airborne Particle Levels Aboard Washington State School Buses  

UK PubMed Central (United Kingdom)

School buses contribute substantially to childhood air pollution exposures yet they are rarely quantified in epidemiology studies. This paper characterizes fine particulate matter (PM2.5)...Full Text Available

2008-10-01

169

Physical fitness and occupational demands of the Belfast ambulance service.  

UK PubMed Central (United Kingdom)

The objectives of this study were to evaluate the current fitness of an area ambulance service based in Belfast and to quantify the physiological demands of accident and emergency work. From a total...Full Text Available

1991-09-01

170

Physical Morphology and Quantitative Characterization of Chemical Changes of Weathered PVC/Pine Composites.  

Science.gov (United States)

This study investigated weathering effects on polyvinyl chloride (PVC) based wood plastic composites (WPC), with a focus on the color and structure that is attributed to the material composition. It is directed towards quantifying the main chemical modifi...

2009-01-01

171

Online quasi-continuous measurement of organic acids in the atmosphere  

Energy Technology Data Exchange (ETDEWEB)

The concentration of some organic acids in the atmosphere was determined using a wet effluent diffusion denuder-aerosol collector coupled with Ion Chromatography. Three organic acids and four inorganic anions were identified and quantified in the air sample, taken from the backyard of PSI. (author)

2002-03-01

172

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI  

UK PubMed Central (United Kingdom)

Spinal cord injury (SCI) is a debilitating disorder, which produces profound deficits in volitional motor control. Following medical stabilization, recovery from SCI typically involves long term rehabilitation....Full Text Available

173

In situ nanoindentation in a transmission electron microscope  

Science.gov (United States)

This dissertation presents the development of the novel mechanical testing technique of in situ nanoindentation in a transmission electron microscope (TEM). This technique makes it possible to simultaneously observe and quantify the mechanical behavior of nano-scale volumes of solids.

2002-12-02

174

Heritability of Lumbar Trabecular Bone Mechanical Properties in Baboons  

UK PubMed Central (United Kingdom)

Genetic effects on mechanical properties have been demonstrated in rodents, but not confirmed in primates. Our aim was to quantify the proportion of variation in vertebral trabecular bone mechanical...Full Text Available

2010-03-01

175

Evaluation of patients' assessment of day hospital care.  

UK PubMed Central (United Kingdom)

The method of linear analogue self-assessment (LASA) was used to quantify the views concerning day care which were held by patients attending a geriatric day hospital. The results suggest that day hospitals...Full Text Available

1977-09-01

176

Evaluating the Nickel Content in Metal Alloys and the Threshold for Nickel-Induced Allergic Contact Dermatitis  

UK PubMed Central (United Kingdom)

Many patients are currently suffering from nickel (Ni)-induced allergic contact dermatitis (ACD). There have been few Korean studies dealing with the threshold of Ni-induced ACD and quantifying the...Full Text Available

2008-04-01

177

Elevated Levels of Volatile Organic Carcinogen and Toxicant Biomarkers in Chinese Women Who Regularly Cook at Home  

UK PubMed Central (United Kingdom)

BackgroundEpidemiologic studies associate lung cancer in non-smoking Chinese women with Chinese-style wok cooking. Our goal was to quantify carcinogen and toxicant...Full Text Available

2010-05-01

178

Effect of pH and Temperature on Denitrification Gene Expression and Activity in Pseudomonas mandelii?  

UK PubMed Central (United Kingdom)

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

2009-06-01

179

Effect of Breast Milk Lead on Infant Blood Lead Levels at 1 Month of Age  

UK PubMed Central (United Kingdom)

Nursing infants may be exposed to lead from breast milk, but relatively few data exist with which to evaluate and quantify this relationship. This route of exposure constitutes a potential infant hazard...Full Text Available

2004-10-01

180

Detection and Analysis of Tumor Fluorescence Using a Two-Photon Optical Fiber Probe  

UK PubMed Central (United Kingdom)

The utility of a two-photon optical fiber fluorescence probe (TPOFF) for sensing and quantifying tumor fluorescent signals was tested in vivo. Xenograft tumors were developed in athymic mice using MCA207...Full Text Available

2004-06-01

181

Deploying Flowbee Tripod  

USGS Gallery

As part of an investigation of the mechanisms of coastal change in the Carolinas (http://woodshole.er.usgs.gov/project-pages/cccp/index.html), instrumented tripods were deployed on Diamond Shoals near Cape Hatteras, NC. These tripods recorded data quantifying the currents, waves, turbidity, temperat...

2010-01-26

182

Comparison of Optical and SEM BSE Imaging Techniques for Quantifying Alpha-Beta Titanium Alloy Microstructures (Preprint).  

Science.gov (United States)

Quantitative metallography is often used to confirm the proper processing of aerospace metallic materials. A microstructural feature of great importance for titanium alloys processed in the alpha-beta phase field is the volume fraction of primary alpha. S...

2006-01-01

183

Community-based incidence of acute renal failure  

UK PubMed Central (United Kingdom)

There is limited information about the true incidence of acute renal failure (ARF). Most studies could not quantify disease frequency in the general population as they are hospital-based and...Full Text Available

2007-07-01

184

Augmenting Clinical Evaluation of Hemiparetic Arm Movement With a Laboratory-Based Quantitative Measurement of Kinematics as a Function of Limb Loading  

UK PubMed Central (United Kingdom)

BackgroundKinematic and kinetic measurements used in laboratory settings can quantify upper extremity movement impairment following stroke, but their relationship...Full Text Available

2008-01-01

185

Alcohol-folate interactions in women's oral cancer risk: A prospective cohort study  

UK PubMed Central (United Kingdom)

BackgroundThe aim of this cohort study was to quantify the effect of alcohol in the risk of oral cancer in different strata of folate intake, controlling for known...Full Text Available

2010-10-01

186

A field study on the effects of dietary monensin on milk production and milk composition in dairy cows  

UK PubMed Central (United Kingdom)

The objectives of this study were to quantify the effect of 16 ppm of dietary monensin on milk production and composition of dairy cows, and to investigate factors having a potential impact on this...Full Text Available

2010-04-01

187

Seismic and Rockphysics Diagnostics fo Multiscale Reservoir Textures  

Energy Technology Data Exchange (ETDEWEB)

We have continued to finish up our work on analyzing relationships between elastic properties and rock microstructure. We have worked on theoretical models for the effects of sorting and packing on elastic moduli and seismic velocities. After analyzing the scanning acoustic images of shales to quantify textures at different scales, we are now using theoretical inclusion models to quantify the elastic property variation with texture. In the closing phases of this project most of our efforts are now focused on writing up the results and preparing the final reports.

2005-02-01

188

Correlations in Werner States  

International Nuclear Information System (INIS)

Werner states are paradigmatic examples of quantum states and play an innovative role in quantum information theory. In investigating the correlating capability of Werner states, we find the curious phenomenon that quantum correlations, as quantified by the entanglement of formation, may exceed the total correlations, as measured by the quantum mutual information. Consequently, though the entanglement of formation is so widely used in quantifying entanglement, it cannot be interpreted as a consistent measure of quantum correlations per se if we accept the folklore that total correlations are measured (or rather upper bounded) by the quantum mutual information.

2008-02-15

189

A framework for the financial evaluation of household biogas plants in India  

Energy Technology Data Exchange (ETDEWEB)

A generalised procedure for quantifying the benefits of household biogas plants is presented. The sensitivity of the procedure to the uncertainty in input prices is reduced through the assumption of incremental benefits from the biogas plant. These benefits are quantified in terms of the quantity of fuelwood for which the biogas substitutes in cooking, the quantity of kerosene replaced through the use of biogas for lighting and the diesel fuel displaced through the use of a biogas fuelled dual-fuel engine for motive power. Sensitivity of the monetary benefits for these parameters is examined in order to identify variables which influence the viability of the technology to the end user. (author).

1990-01-01

190

Steady-state levels of G-protein beta-subunit expression are regulated by treatment of cells with bacterial toxins  

International Nuclear Information System (INIS)

Cultures of 3T3-L1 cells were incubated with either 10 ng/ml cholera toxin or 10 ng/ml pertussis toxin from 4 days prior to the initiation of differentiation and throughout the subsequent incubation. Toxin concentrations were sufficient to completely prevent the labelling of alpha-subunits with ["3"2P]NAD"+ and pertussis toxin and to prevent by more than 90% the labelling with ["3"2P]NAD"+ and cholera toxin in membranes prepared from these cells. Neither toxin prevented the differentiation to the adipocyte phenotype. Neither toxin prevented the increases in the relative amounts of G-proteins which occur upon differentiation. Both toxins dramatically decreased the amount of beta-subunits. As measured by quantitative immunoblotting with antisera specific for both the 35 kDa and 36 kDa beta-subunits, levels of beta-subunit were decreased by more than 50% of steady-state level of control cells. Thus, bacterial toxins which modifies G-protein alpha-subunits are capable ...

1987-06-07

191

Comparison of newer synthetic and biological wound dressings.  

Science.gov (United States)

In 18 piglets, weighing 10-15 kg, third-degree burns or full-thickness skin excisions of 4 X 4 cm were inflicted. The effect of five dressing materials on adhesiveness to the wounds, appearance, conformability, wound contraction, bacterial count, and morphology of the wound was studied at the end of the seventh and fourteenth days without dressing changes. In 11 piglets with a burn wound, the most adherent dressing was collagen sponge(CS), followed by polyurethane sponge (PU), pigskin xenograph (PS), and xeroform. CS more effectively debrided the wound from coagulated necrotic tissue than the other dressings. Wound contraction was maximal with CS dressing (52%), followed by PU (44%), xeroform (32%), and PS (27%). In another seven piglets with full-thickness excised wounds, a velour dressing made of polytetrafluoroethylene (PTFE) or PU adhered significantly more than CS or PS. Wound contraction was greater with CS (37%) or PTFE (35%) than with PS (23%) or PU (18%). ...

1981-06-01

192

Analysis of S-adenosylmethionine and related sulfur metabolites in bacterial isolates of Pseudomonas aeruginosa (BAA-47) by liquid chromatography/electrospray ionization coupled to a hybrid linear quadrupole ion trap and Fourier transform ion cyclotron resonance mass spectrometry  

British Library Electronic Table of Contents (United Kingdom)

A comprehensive and highly selective method for detecting in bacterial supernatants a modified sulfur nucleoside, S-adenosyl-L-methionine (SAM), and its metabolites, i.e., S-adenosylhomocysteine (SAH), adenosine (Ado), 5prime-deoxy-5prime-methylthioadenosine (MTA), adenine (Ade), S-adenosyl-methioninamine (dcSAM), homocysteine (Hcy) and methionine (Met), was developed. The method is based on reversed-phase liquid chromatography with positive electrospray ionization (ESI+) coupled to a hybrid linear quadrupole ion trap (LTQ) and 7-T Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). A gradient elution was employed with a binary solvent of 0.05 M ammonium formate at pH 4 and acetonitrile. The assay involves a simultaneous cleanup of cell-free bacterial broths by solid-pha...

2009-01-01

193

Effects of human serum on bacterial competition with neutrophils for molecular oxygen.  

Science.gov (United States)

A dialyzable factor(s) in human serum is known to stimulate gonococcal oxygen consumption. Its effect on other human pathogens was investigated. A 10% serum solution increased peak O2 consumption for Escherichia coli and Staphylococcus aureus to 157% (P less than 0.05) and 199% (P less than 0.02), respectively, of their O2 consumption when suspended in Hanks balanced salt solution, compared with a 356% increase for Neisseria gonorrhoeae with serum. Dialyzed serum lacked stimulatory capacity. Bacteria, serum, and neutrophils are often incubated to evaluate neutrophil bactericidal activity. Samples of 10(8) N. gonorrhoeae, S. aureus, and E. coli turned resazurin colorless (anaerobic conditions, Eh less than -42 mV) after 7.4, 13.3, and 15.1 min, respectively. Because neutrophil formation of reactive oxygen intermediates requires ambient O2, the effect of live bacteria and serum on this process was explored. After 5 min of incubation of 10(8) N. gonorrhoeae or S. aureus in 10% normal or ...

1986-06-01

194

Vaginal Matrix Metalloproteinase Levels in Pregnant Women With Bacterial Vaginosis  

British Library Electronic Table of Contents (United Kingdom)

Objective To compare matrix metalloproteinase (MMP)-8 and MMP-9 levels in the vaginal secretions of pregnant women with or without asymptomatic bacterial vaginosis (BV). Methods In this study, vaginal levels and molecular forms of MMP-8 and MMP-9 were studied in 36 pregnant women between 28 and 34 weeks of gestation with asymptomatic BV and 41 pregnant women, matched for gestational age, without BV. Results Vaginal MMP-8 concentrations were significantly higher (P = .023) in BV-positive women. There was no significant difference in MMP-9 levels between healthy pregnant controls and BV-positive pregnant women. The presence of MMP-8 was confirmed by a 38-kd band on Western blots. Conclusions Our findings show that BV is associated with increased levels of MMP-8 in vaginal fluid. Increased pr...

2006-01-01

195

Testing an agent-based model of bacterial cell motility: How nutrient concentration affects speed distribution  

British Library Electronic Table of Contents (United Kingdom)

We revisit a recently proposed agent-based model of active biological motion and compare its predictions with own experimental findings for the speed distribution of bacterial cells, Salmonella typhimurium. Agents move according to a stochastic dynamics and use energy stored in an internal depot for metabolism and active motion. We discuss different assumptions of how the conversion from internal to kinetic energy d(v) may depend on the actual speed, to conclude that d 2 v ? with either ? = 2 or 1 ? < 2 are promising hypotheses. To test these, we compare the model?s prediction with the speed distribution of bacteria which were obtained in media of different nutrient concentration and at different times. We find that both hypotheses are in line with the experimental observations, with ? bet...

2011-01-01

196

Synergistic interaction of eugenol with antibiotics against Gram negative bacteria  

British Library Electronic Table of Contents (United Kingdom)

Eugenol, the principal chemical component of clove oil from Eugenia aromatica has been long known for its analgesic, local anesthetic, anti-inflammatory, and antibacterial effects. The interaction of the eugenol with ten different hydrophobic and hydrophilic antibiotics was studied against five different Gram negative bacteria. The MIC of the combination was found to decrease by a factor of 5-1000 with respect to their individual MIC. This synergy is because of the membrane damaging nature of eugenol, where 1mM of its concentration is able to damage nearly 50% of the bacterial membrane. Eugenol was also able to enhance the activities of lysozyme, Triton X-100 and SDS in damaging the bacterial cell membrane. The hydrophilic antibiotics such as vancomycin and b-lactam antibiotics which have ...

2009-01-01

197

Susceptibility to invasive bacterial infections in children with sickle cell disease  

British Library Electronic Table of Contents (United Kingdom)

Individuals with sickle cell disease (SCD) demonstrate an increased susceptibility to invasive bacterial infections (IBI). The most common organisms causing IBI are Streptococcus pneumoniae, nontyphi Salmonella species and Haemophilus influenzae type b (Hib). IBI are the most common causes of death in children below 5 years of age with SCD. Increased susceptibility to IBI is because of several factors including dysfunctional antibody production and opsonophagocytosis as well as defective splenic clearance. Early diagnosis of Hib and pneumococcal infections combined with antibiotic prophylaxis and immunization programs, could lead to significant improvements in mortality, especially in Africa. Pediatr Blood Cancer. 2010;55:401-406. Copyright 2010 Wiley-Liss, Inc.

2010-01-01

198

Regulation and secretion of Xanthomonas virulence factors  

British Library Electronic Table of Contents (United Kingdom)

Abstract Plant pathogenic bacteria of the genus Xanthomonas cause a variety of diseases in economically important monocotyledonous and dicotyledonous crop plants worldwide. Successful infection and bacterial multiplication in the host tissue often depend on the virulence factors secreted including adhesins, polysaccharides, LPS and degradative enzymes. One of the key pathogenicity factors is the type III secretion system, which injects effector proteins into the host cell cytosol to manipulate plant cellular processes such as basal defense to the benefit of the pathogen. The coordinated expression of bacterial virulence factors is orchestrated by quorum-sensing pathways, multiple two-component systems and transcriptional regulators such as Clp, Zur, FhrR, HrpX and HpaR. Furthermore, virule...

2010-01-01

199

Nationwide surveillance of bacterial respiratory pathogens conducted by the Japanese Society of Chemotherapy in 2008: general view of the pathogens? antibacterial susceptibility  

British Library Electronic Table of Contents (United Kingdom)

For the purpose of nationwide surveillance of the antimicrobial susceptibility of bacterial respiratory pathogens collected from patients in Japan, the Japanese Society of Chemotherapy conducted a third year of nationwide surveillance during the period from January to April 2008. A total of 1,097 strains were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections. Susceptibility testing was evaluable with 987 strains (189 Staphylococcus aureus, 211 Streptococcus pneumoniae, 6 Streptococcus pyogenes, 187 Haemophilus influenzae, 106 Moraxella catarrhalis, 126 Klebsiella pneumoniae, and 162 Pseudomonas aeruginosa). A total of 44 antibacterial agents, including 26 ?-lactams (four penicillins, three penicillins in combination with ?-lacta...

2011-01-01

200

Leaching of zinc sulfide by Thiobacillus ferrooxidans: Bacterial oxidation of the sulfur product layer increases the rate of zinc sulfide dissolution at high concentrations of ferrous ions  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the results of leaching experiments conducted with and without Thiobacillus ferroxidans at the same conditions in solution. The extent of leaching of ZnS with Bacteria is significantly higher than that without bacteria at high concentrations of ferrous ions. A porous layer of elemental sulfur is present on the surfaces of the chemically leached particles, which no sulfur is present on the surfaces of the bacterially leached particles. The analysis of the data using the shrinking-core model shows that the chemical leaching of ZnS is limited by the diffusion of ferrous ions through the sulfur product layer at high concentrations of ferrous ions. The analysis of the data shows that diffusion through the product layer does not limit the rate of dissolution when bacteria are present. This suggests that the action of T.ferroxidans in oxidizing the sulfur formed on the particle surface is to remove the barrier to diffusion by ferrous ions.

1999-12-01

201

In situ synthesis of silver chloride nanoparticles into bacterial cellulose membranes  

British Library Electronic Table of Contents (United Kingdom)

In situ synthesis of silver chloride (AgCl) nanoparticles was carried out under ambient conditions in nanoporous bacterial cellulose (BC) membranes as nanoreactors. The growth of the nanoparticles was readily obtained by alternating dipping of BC membranes in the solution of silver nitrate or sodium chloride followed by a rinse step. X-ray diffraction (XRD) patterns indicated the existence of AgCl nanoparticles in the BC and scanning electron microscopy (SEM) images showed that the AgCl nanoparticles well dispersed on the surface of BC and penetrated into the BC network. The AgCl nanoparticle-impregnated BC membranes exhibited high hydrophilic ability and strong antimicrobial activity against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). The preparative proced...

2009-01-01

202

Comparison of iodine and glutaraldehyde as surface disinfectants for red porgy (Pagrus pagrus) and white sea bream (Diplodus sargus sargus) eggs  

British Library Electronic Table of Contents (United Kingdom)

Abstract The efficacy of iodine and glutaraldehyde as fish egg surface disinfectants were assessed in red porgy (Pagrus pagrus) and white sea bream (Diplodus sargus sargus) eggs, two species of interest for Mediterranean aquaculture. Iodine was effective in reducing the bacterial load of the 1-day-old eggs when applied at 50 mg L-1 for 5 min. The same concentration did not cause any significant change in hatching success or survival of the larvae for the first 5 days. Glutaraldehyde failed to reduce the bacterial load of the fish eggs at concentrations that were safe for the eggs (100 mg L-1 for 5 min), as it had a significant effect in preventing hatching of the developed embryo. Disinfecting 0-day-old eggs with iodine resulted in a significant reduction of hatching percentage, while larv...

2007-01-01

203

Biosorption of lead from aqueous solutions by Bacillus strains possessing heavy-metal resistance  

British Library Electronic Table of Contents (United Kingdom)

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...

2011-01-01

204

Aerogels from Unaltered Bacterial Cellulose: Application of scCO2 Drying for the Preparation of Shaped, Ultra-Lightweight Cellulosic Aerogels  

British Library Electronic Table of Contents (United Kingdom)

Bacterial cellulose produced by the gram-negative bacterium Gluconacetobacter xylinum was found to be an excellent native starting material for preparing shaped ultra-lightweight cellulose aerogels. The procedure comprises thorough washing and sterilization of the aquogel, quantitative solvent exchange and subsequent drying with supercritical carbon dioxide at 40 degreeC and 100 bar. The average density of the obtained dry cellulose aerogels is only about 8 mg cm-3 which is comparable to the most lightweight silica aerogels and distinctly lower than all values for cellulosic aerogels obtained from plant cellulose so far. SEM, ESEM and nitrogen adsorption experiments at 77 K reveal an open-porous network structure that consists of a comparatively high percentage of large mesopores and small...

2010-01-01

205

Ability of a ?minimum?? microbial food web model to reproduce response patterns observed in mesocosms manipulated with N and P, glucose, and Si  

British Library Electronic Table of Contents (United Kingdom)

We compared an idealised mathematical model of the lower part of the pelagic food web to experimental data from a mesocosm experiment in which the supplies of mineral nutrients (nitrogen and phosphorous), bioavailable dissolved organic carbon (BDOC, as glucose), and silicate were manipulated. The central hypothesis of the experiment was that bacterial consumption of BDOC depends on whether the growth rate of heterotrophic bacteria is limited by organic-C or by mineral nutrients. In previous work, this hypothesis was examined qualitatively using a conceptual food web model. Here we explore the extent to which a ?simplest possible?? mathematical version of this conceptual model can reproduce the observed dynamics. The model combines algal?bacterial competition for mineral nutrients (phosphor...

2007-01-01

206

[Intraspecies antagonism of Sh. flexneri in an HEp-2 cell line model].  

Science.gov (United States)

The authors describe an effect of suppression of invasion of the guinea pig eye conjunctiva and the HEp-2 epithelial cells by virulent Sh. flexneri bacilli, with a simultaneous administration of the same dose of avirulent shigella mutants, genetically connected with them. The data of morphological study and experiments with 3H-glucose labeled shigellae carried out on the cell species model indicated that the bacterial competition for the specific sites for absorption on the epithelial cells underlay the observed phenomenon. PMID:331774

1977-06-01

207

Vertical and Horizontal Variations in the Physiological Diversity of the Aerobic Chemoheterotrophic Bacterial Microflora in Deep Southeast Coastal Plain Subsurface Sediments  

UK PubMed Central (United Kingdom)

Aerobic chemoheterotrophic bacteria were isolated from surface soils and coastal plain subsurface (including deep aquifer) sediments (depths to 265 m) at a study site near Aiken, S.C., by plating on...Full Text Available

1989-05-01

208

The hrpK Operon of Pseudomonas syringae pv. tomato DC3000 Encodes Two Proteins Secreted by the Type III (Hrp) Protein Secretion System: HopB1 and HrpK, a Putative Type III Translocator  

UK PubMed Central (United Kingdom)

Pseudomonas syringae is a gram-negative bacterial plant pathogen that is dependent on a type III protein secretion system (TTSS) and the effector proteins it translocates into plant...Full Text Available

2005-01-01

209

The ecological role of bacteriocins in bacterial competition.  

Science.gov (United States)

Bacteriocins are an abundant class of antimicrobial molecules that appear to mediate population dynamics within species. The bacteriocins of Escherichia coli have served as a model for exploring the ecological role of these potent toxins. Studies suggest that colicins provide a competitive edge in nutrient-poor environments and that there might be a trade-off between the costs and benefits of colicin production. PMID:10203843

1999-03-01

210

Stabilization of Plutonium in Subsursface Environments via Microbial Reduction and Biofilm Formation  

Energy Technology Data Exchange (ETDEWEB)

Our work is towards mechanistically understanding interactions of unsaturated bacterial biofilms and their extracellular polymeric substances (EPS) with actinide metals and metal surrogates under vadose zone conditions. Because metal contaminants in the vadose zone co-occur with organic pollutants, some of our work has included experiments with organic pollutants.

2005-06-01

211

Prevalence of Actinobacillus pleuropneumoniae, Actinobacillus suis, Haemophilus parasuis, Pasteurella multocida, and Streptococcus suis in representative Ontario swine herds  

UK PubMed Central (United Kingdom)

Tonsillar and nasal swabs were collected from weanling pigs in 50 representative Ontario swine herds and tested for the presence of 5 important bacterial upper respiratory tract pathogens. All but 1...Full Text Available

2008-04-01

212

Phase transitions in multiplicative competitive processes  

Science.gov (United States)

We introduce a discrete multiplicative process as a generic model of competition. Players with different abilities successively join the game and compete for finite resources. Emergence of dominant players and evolutionary development occur as a phase transition. The competitive dynamics underlying this transition is understood from a formal analogy to statistical mechanics. The theory is applicable to bacterial competition, predicting novel population dynamics near criticality.

2005-07-01

213

Nod2 sensing of lysozyme-digested peptidoglycan promotes macrophage recruitment and clearance of S. pneumoniae colonization in mice.  

Science.gov (United States)

Streptococcus pneumoniae colonizes the mucosal surface of the human upper respiratory tract. A colonization event is gradually cleared through phagocytosis by monocytes/macrophages that are recruited to the airway lumen. Here, we sought to define the bacterial and host factors that promote monocyte/macrophage influx and S. pneumoniae clearance using intranasal bacterial challenge in mice. We found that the recruitment of monocytes/macrophages required their expression of the chemokine receptor CCR2 and correlated with expression of the CCR2 ligand CCL2. Production of CCL2 and monocyte/macrophage recruitment were deficient in mice lacking digestion of peptidoglycan by lysozyme (LysM) and cytosolic sensing of the products of digestion by Nod2. Ex vivo macrophages produced CCL2 following bacterial uptake, digestion by LysM, and sensing of peptidoglycan by Nod2. Sensing of digested peptidoglycan by Nod2 also required the ...

2011-08-15

214

Mutations Affecting Motifs of Unknown Function in the Central Domain of Nitrogen Regulatory Protein C  

UK PubMed Central (United Kingdom)

The positive control function of the bacterial enhancer-binding protein NtrC resides in its central domain, which is highly conserved among activators of ς54 holoenzyme. Previous...Full Text Available

1999-09-01

215

Isolation of a bacterial host selective for bacteriophage T4 containing cytosine in its DNA.  

UK PubMed Central (United Kingdom)

An Escherichia coli B strain, B834 galU56, has been isolated which supports growth of bacteriophage T4 with cytosine in its DNA while restricting growth of T4 with hydroxymethylcytosine. This host is...Full Text Available

1978-09-01

216

Intrahepatic cholangiocarcinoma presenting as liver abscess: report of two cases  

International Nuclear Information System (INIS)

Intrahepatic cholangiocarcinoma is the second most common primary malignant hepatic neoplasm. We describe two cases of intrahepatic cholangiocarcinoma which initially presented as liver abscess both clinically and radiologically. Mucin-hypersecretion from the tumor cells and extensive necrosis or secondary bacterial infection was responsible for the radiologic appearance of a liver abscess.=20

1998-10-01

217

Intracellular activity of the peptide antibiotic NZ2114: studies with Staphylococcus aureus and human THP-1 monocytes, and comparison with daptomycin and vancomycin  

DEFF Research Database (Denmark)

Staphylococcus aureus survives inside eukaryotic cells. Our objective was to assess the activity of NZ2114, a novel peptidic antibiotic, against intracellular S. aureus in comparison with established antistaphylococcal agents acting on the bacterial envelope with a distinct mechanism.

2010-01-01

218

First Outbreak of Multidrug-Resistant Klebsiella pneumoniae Producing both SHV-12-Type Extended-Spectrum ?-Lactamase and DHA-1-Type AmpC ?-Lactamase at a Korean Hospital  

UK PubMed Central (United Kingdom)

PurposeCoexistence of different classes of β-lactamases in a single bacterial isolate may pose diagnostic and therapeutic challenges. We investigated a spread of Klebsiella...Full Text Available

2008-02-29

219

Detection of Atopobium vaginae in postmenopausal women by cultivation-independent methods warrants further investigation.  

Science.gov (United States)

We sequenced 16S rRNA genes from the vaginal swab contents of a postmenopausal woman with asymptomatic bacterial vaginosis (BV). Sequences from Atopobium vaginae were the most commonly detected. In a survey of 35 other postmenopausal women, this organism was detected in 44% with BV but not in any subjects deemed healthy. PMID:15071062

2004-04-01

220

Campylobacter jejuni, C. coli, and C. lari naturally present in Leghorn laying hens and the antibiotic resistance profiles of these organisms  

Science.gov (United States)

Campylobacter spp. are present in the intestinal tract and internal tissues of broiler breeder and broiler chickens. Campylobacter spp. are known to cause acute bacterial gastroenteritis in humans and raw poultry products have been implicated as a significant source of these infections. The object...

221

Blockade of catecholamine-induced growth by adrenergic and dopaminergic receptor antagonists in Escherichia coli O157:H7, Salmonella enterica and Yersinia enterocolitica  

UK PubMed Central (United Kingdom)

BackgroundThe ability of catecholamines to stimulate bacterial growth was first demonstrated just over a decade ago. Little is still known however, concerning the nature of the putative...Full Text Available

222

A modeling study by response surface methodology and artificial neural network on culture parameters optimization for thermostable lipase production from a newly isolated thermophilic Geobacillus sp. strain ARM  

UK PubMed Central (United Kingdom)

BackgroundThermostable bacterial lipases occupy a place of prominence among biocatalysts owing to their novel, multifold applications and resistance to high temperature and other...Full Text Available

223

Subclinical interstitial lung involvement in rheumatic diseases. Correlations of high-resolution Computed Tomography patterns with functional and cytologic findings  

International Nuclear Information System (INIS)

The aims of this study were to quantify the severity and extent of subclinical interstitial lung disease as depicted on HRCT and to study the relationship between the patterns of lung disease quantified by HRCT and the functional parameters and bronchoalveolar lavage findings in patients with rheumatic diseases. The results confirm that HRCT is a sensitive tool in detecting interstitial lung disease in patients with rheumatic diseases with no signs and symptoms of pulmonary involvement. The relationship between the different HRCT patterns and bronchoalveolar lavage cell profiles can identify patients at higher risk of developing irreversible lung fibrosis. A long-term, prospective follow-up study is needed to determine whether these patients will develop over pulmonary disease.

1999-01-01

224

Quantifying the thermal flowering rates of eighteen species of annual bedding plants  

British Library Electronic Table of Contents (United Kingdom)

The effect of mean daily air temperature (MDT) on flowering rate (the reciprocal of days to flower) was quantified for 18 species of annual bedding plants. Plants were grown in environmental growth chambers at constant air temperature set points of 5, 7.5, 10, 15, 25, or 30^oC and under an irradiance of 160-180mmolm^-^2s^-^1, with a 16-h photoperiod. Nonlinear mathematical equations were developed to predict the effect of MDT on flowering rate and to estimate the base, optimum, and maximum temperatures (Tmin, Topt, and Tmax), which are the temperatures at which flowering rates are zero (low temperature), maximal, and zero once again (high temperature), respectively. The estimated Tmin varied among species and ranged from 1.1^oC in French marigold (Tagetes patula L.) to 9.9^oC in angelonia ...

2011-01-01

225

Methods for proving the equivalency of detonator performance  

Energy Technology Data Exchange (ETDEWEB)

One of the challenges facing engineers is developing newer, safer detonators that are equivalent to devices currently in use. There is no clear consensus on an exact method for drawing equivalence of detonators. This paper summarizes our current efforts to develop diagnostics addressing various aspects of detonator design to better quantify and prove equivalency. We consider various optical techniques to quantify the output pressure and output wave shape. The development of a unique interpretation of streak camera breakouts, known as the apparent center of initiation, will be discussed as a metric for detonation wave shape. Specific examples apply these techniques to the comparison of a new laser-driven detonator with an existing exploding bridgewire (EBW) detonator. Successes and short-comings of the techniques will be discussed.

2009-01-01

226

Mapping burned areas and burn severity patterns in SW Australian eucalypt forest using remotely-sensed changes in leaf area index  

British Library Electronic Table of Contents (United Kingdom)

Remote sensing is the most practical method available to managers of fire-prone forests for quantifying and mapping fire impacts. Differenced Normalised Burn Ratio (?NBR) is among the most widely used spectral indices for the mapping of burn severity but is difficult to interpret in terms of fire-related changes in key biophysical attributes and processes. We propose to quantify burn severity as a change in the leaf area index (?LAI) of a stand. LAI is a key biophysical attribute of forests, and is central to understanding their water and carbon cycles. Previous studies have suggested that changes in canopy LAI may be a major contributor to ?NBR and to the composite burn index (CBI) that is frequently used in combination with the NBR to assess burn severity on the ground. We applied remote...

2008-01-01

227

Language morphology offset: Text classification on a Croatian-English parallel corpus  

British Library Electronic Table of Contents (United Kingdom)

We investigate how, and to what extent, morphological complexity of the language influences text classification using support vector machines (SVM). The Croatian-English parallel corpus provides the basis for direct comparison of two languages of radically different morphological complexity. We quantified, compared, and statistically tested the effects of morphological normalisation on SVM classifier performance based on a series of parallel experiments on both languages, carried over a large scale of different feature subset sizes obtained by different feature selection methods, and applying different levels of morphological normalisation. We also quantified the trade-off between feature space size and performance for different levels of morphological normalisation, and compared the resul...

2008-01-01

228

Example of second-law efficiency of solar-thermal cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

Properly quantified performance of a solar-thermal cavity receiver must not only account for the energy gains and losses as dictated by the First Law of thermodynamics, but it must also account for the quality of that energy. Energy quality can only be determined from the Second Law. In this paper, an equation developed for the Second-Law efficiency of a cavity receiver is presented as an evolution from the definition of available energy or ''availability'' (occasionally called exergy). The variables required are all either known or readily determined. The importance of considering the Second-Law is emphasized by a comparison of the First- and Second-Law efficiencies around an example of data collected from two receivers that were designed for different purposes, where the attempt was made to demonstrate that a Second-Law approach to quantifying the performance of a solarthermal cavity receiver lends more ...

1986-02-01

229

Environmental costs and benefits case study: nuclear power plant. Quantification and economic valuation of selected environmental impacts/effects. Final report  

International Nuclear Information System (INIS)

This case study is an application, to a nuclear power plant, of the methodology for quantifying environmental costs and benefits, contained in the regional energy plan, adopted in April, 1983, by the Northwest Power Planning Council, pursuant to Public Law 96-501.The study is based on plant number 2 of the Washington Public Power Supply System (WNP-2), currently nearing completion on the Hanford Nuclear Reservation in eastern Washington State. This report describes and documents efforts to quantify and estimate monetary values for the following seven areas of environmental effects: radiation/health effects, socioeconomic/infrastructure effects, consumptive use of water, psychological/health effects (fear/stress), waste management, nuclear power plant accidents, and decommissioning costs. 103 references.

230

Dialysis membrane for separation on microchips  

Energy Technology Data Exchange (ETDEWEB)

Laser-induced phase-separation polymerization of a porous acrylate polymer is used for in-situ fabrication of dialysis membranes inside glass microchannels. A shaped 355 nm laser beam is used to produce a porous polymer membrane with a thickness of about 15 .mu.m, which bonds to the glass microchannel and forms a semi-permeable membrane. Differential permeation through a membrane formed with pentaerythritol triacrylate was observed and quantified by comparing the response of the membrane to fluorescein and fluorescently tagging 200 nm latex microspheres. Differential permeation was observed and quantified by comparing the response to rhodamine 560 and lactalbumin protein in a membrane formed with SPE-methylene bisacrylamide. The porous membranes illustrate the capability for the present technique to integrate sample cleanup into chip-based analysis systems.

2010-07-13

231

Blood flow quantification with MRI using the phase mapping method. Moeglichkeiten und Grenzen der Blutflussquantifizierung peripherer arterieller Gefaesse mit der MRT unter Anwendung des Phase-Mapping-Verfahrens  

Energy Technology Data Exchange (ETDEWEB)

MRT is able to demonstrate arteries while MR angiography can quantify blood flow by a non-invasive method. In the present paper blood flow measurements were carried out in four selected cases on the basis of phase mapping. In 3 patients with lesions in the pelvis or thigh, angiography was performed in order to localise the stenosis or occlusion and this was followed by qantitative blood flow measurements. The results showed that angiography may not always provide all necessary information concerning a haemodynamically significant stenosis. The method may also be used for quantifying blood flow in the renal arteries and that it has significant advantages over the colour Doppler method. (orig.).

1992-08-01

232

A novel method for quantifying scanner instability in fMRI  

British Library Electronic Table of Contents (United Kingdom)

Abstract A method was developed to quantify the effect of scanner instability on functional MRI data by comparing the instability noise to endogenous noise present when scanning a human. The instability noise was computed from agar phantom data collected with two flip angles, allowing for a separation of the instability from the background noise. This method was used on human data collected at four 3 T scanners, allowing the physiological noise level to be extracted from the data. In a -well-operating- scanner, the instability noise is generally less than 10% of physiological noise in white matter and only about 2% of physiological noise in cortex. This indicates that instability in a well-operating scanner adds very little noise to functional MRI results. This new method allows researcher...

2011-01-01

233

A new method for quantifiable and controlled dosage of particulate matter for in vitro studies: The electrostatic particulate dosage and exposure system (EPDExS)  

British Library Electronic Table of Contents (United Kingdom)

An exposure chamber is described for the quantifiable addition of fine and ultrafine aerosol particulate matter directly to cells and used to demonstrate the in vitro cytotoxicity of fine 1,4-naphthoquinone particles to murine lung epithelial cells. The electrostatic particulate dosage and exposure system (EPDExS) operates on the principle of electrostatic precipitation and is shown to deposit fine and ultrafine aerosol particles directly to cells with 100% efficiency for particle diameters in the range of 40-530nm. This range is not limited by the EPDExS, but rather by the aerosolization method used for this study. Numbers of particles deposited onto the cells are counted with a condensation particle counter, negating any need to calculate or estimate particle exposure. The process of par...

2008-01-01

234

Summary of Omega West Reactor, Level 1, probabilistic risk assessment  

International Nuclear Information System (INIS)

This paper reports on a Level 1 PRA performed on the Omega West Reactor at Los Alamos National Laboratory. A Master Logic Diagram was used to identify possible initiating events. A chi-square distribution was used to quantify initiating event frequencies given that no initiating events have occurred in 30 years of OWR operation. The PRA results are presented as both probability density function and cumulative distribution function curves.

1990-10-04

235

Secondary co-refining of petroleum and coal distillates, and the evaluation of coal cleaning in coal liquefaction  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a research and development project to quantify the effects of cleaning the coal feed on the yield patterns and processing rates for the Liquid Solvent Extraction (LSE) direct coal liquefaction process and to obtain information on the effect of the co-refining of coal-derived and petroleum distillates to premium transport fuels. 6 refs., 25 figs., 40 tabs.

1992-12-31

236

Quantifying octahedral rotations in strained perovskite oxide films.  

Energy Technology Data Exchange (ETDEWEB)

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.

2010-07-20

237

Petroleum waxes in solvent systems  

Energy Technology Data Exchange (ETDEWEB)

Wax appearance temperature (WAT) of three petroleum waxes in different solvent systems under varying thermal conditions has been determined. It is observed that this temperature mainly is a function of the concentration of the wax and the solubility parameter ([delta]) of the solvent taken. This dependence of WAT has been quantified in terms of these variables in the form of mathematical equation and nomographs. (orig.)

1994-01-01

238

PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk  

Energy Technology Data Exchange (ETDEWEB)

Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

2010-03-15

239

Measurement and apportionment of radon source terms for modeling indoor environments  

Energy Technology Data Exchange (ETDEWEB)

This research has two main goals; (1) to quantify mechanisms for radon entry into homes of different types and to determine the fraction of indoor radon attributable to each source and (2) to model and calculate the dose (and therefore alpha particle fluence) to cells in the human and animal tracheobronchial tree that is pertinent to induction of bronchogenic carcinoma from inhaled radon daughters.

1990-01-01

240

Levels and distribution of BCNU in GBM tumors following intratumoral injection of DTI-015 (BCNU-ethanol)  

UK PubMed Central (United Kingdom)

The alkylation products formed by in vitro treatment of DNA with tritium-labeled 1,3-bis(2-chloroethyl)-1-nitrosourea (3H-BCNU) were identified and quantified. Twelve adducts were resolved...Full Text Available

2007-01-01

241

Experts' discussion on the possibility of quantification of the radiation hazard  

International Nuclear Information System (INIS)

Due to the intensity and vast number of subjects, this Bremen experts' discussion, too, could discuss only part of the problem of the possibilitiy to quantify the radiation hazard. One preliminary result is that there is no scientific proof of the harmlessness of radiation exposure during normal operation of a nuclear power plant, either within the plant or in its vicinity. Other results are that some important questions can not be answered yet, and that there are important hints on the dangers even of low radiation doses. (GL).

1978-01-01

242

Effects of 2 commercially-available 9-way killed vaccines on milk production and rectal temperature in Holstein-Friesian dairy cows.  

UK PubMed Central (United Kingdom)

Veterinarians and farmers employing multivalent killed vaccines in lactating dairy cows have reported transient losses in milk production. Few studies have quantified this loss. In this report, effects...Full Text Available

2001-10-01

243

Effectiveness of information provision in reducing risks to the environment  

Environmental Research Database

DescriptionAs part of a wider effort to develop new approaches to evaluating and quantifying the benefits of chemicals regulation, this project will review the effectiveness of existing information provision tools (such as classification and labelling for hazardous properties) in terms of affecting user behaviour. As some EC legislation relating to regulation of chemicals has been in place for some time, an assumption is made that the information provided by it is leading to an improvement in the way chem [continued...

2005-01-30

244

Complex fractal dimensions describe the hierarchical structure of diffusion-limited-aggregate clusters  

Energy Technology Data Exchange (ETDEWEB)

We analyze large diffusion-limited aggregates and uncover a {ital discrete} scaling invariance in their inner structure, which can be quantified by the introduction of a set of {ital complex} fractal dimensions. We provide a theoretical framework and prediction of their values based on renormalization group theory and a previous wavelet analysis. {copyright} {ital 1996 The American Physical Society.}

1996-01-01

245

Clinical helical tomotherapy commissioning dosimetry  

International Nuclear Information System (INIS)

Helical tomotherapy presented many unique dosimetric challenges and solutions during the initial commissioning process, and some of them are presented. The dose calculation algorithm is convolution/superposition based. This requires that the energy fluence spectrum and magnitude be quantified. The methodology for doing so is described. Aspects of the energy fluence characterization that are unique to tomotherapy are highlighted. Many beam characteristics can be measured automatically by an included megavoltage computed tomography imaging system. This greatly improves data collection efficiency.

2003-12-01

246

Temperature and controlled atmosphere effects on efficacy of Muscodor albus as a biofumigant  

British Library Electronic Table of Contents (United Kingdom)

Biofumigation with Muscodor albus was investigated to control four fungal decay pathogens (Phytophthora erythroseptica, Sclerotinia sclerotiorum, Botrytis cinerea and Penicillium expansum) and four bacterial pathogens (Erwinia carotovora pv. carotovora, Pseudomonas fluorescens, Escherichia coli, Listeria innocua) in controlled atmosphere conditions (regular air (20.8% O2+0.03% CO2), high CO2 (20.8% O2+15% CO2) or low O2 (1% O2+0.03% CO2)). In vitro experiments involved 48h exposure to M. albus at 3degreeC or 20degreeC, in vivo experiments involved 72h exposure to M. albus at 3degreeC. In vitro biofumigation with M. albus in regular air at 20degreeC killed all the pathogens. Bacterial growth was best controlled by M. albus at 20degreeC regardless of atmospheric conditions whereas fungal gro...

2008-01-01

247

Sulfur and carbon cycling in a flue gas desulfurization sludge disposal site.  

Science.gov (United States)

Products of a power plant flue gas desulfurization scrubber are discharged into a pond as sludge consisting of calcite (initial delta13C 3.2-3.8 per thousand), gypsum (initial delta34S 7.6-8.6 per thousand), and aqueous solution. Reducing conditions exist below a boundary that appears to move vertically as a function of changes in pond water level. Under reducing conditions, bacteria partially reduce aqueous sulfate to low-delta34S sulfide, consuming organic carbon and generating low-delta13C bicarbonate. Under oxidizing conditions, sulfide is converted to sulfate, leading to calcite dissolution, gypsum precipitation, and isotopic re-equilibration of remaining calcite with dissolved bicarbonate near the pond surface. The gypsum has delta34S near 6 per thousand, and calcite has delta13C as low as -1.7 per thousand; the changes from initial values correspond to predictions based on isotopic balance and reaction stoichiometry. The pond largely contains the products of ...

2003-04-01

248

Impact of Bifidobacterium animalis subsp. lactis BB-12 and, Lactobacillus acidophilus LA-5-containing yoghurt, on fecal bacterial counts of healthy adults  

British Library Electronic Table of Contents (United Kingdom)

This randomized, placebo-controlled, double blind, parallel dose-response study investigated the impact of 4-week commercial yoghurt consumption supplemented with Bifidobacterium animalis subsp. lactis (BB-12) and Lactobacillus acidophilus (LA-5) on fecal bacterial counts of healthy adults. Fifty-eight volunteers were randomly assigned to three different groups: 1. placebo (no probiotic, no starter and no green tea extract); 2. Yoptimal (10^9cfu/100g of BB-12 and LA-5 and 40mg of green tea extract) and 3. Yoptimal-10 (10^1^0cfu/100g of BB-12, 10^9cfu/100g of LA-5 and 40mg of green tea extract). These yoghurt products also contained Lactobacillus delbrueckii subsp. bulgaricus (10^7cfu/100g) and Streptococcus thermophilus (10^1^0cfu/100g). The quantitative PCR (qPCR) results showed that ther...

2011-01-01

249

Geochemical study on origin of natural gases in Japanese oil and gas fields  

Energy Technology Data Exchange (ETDEWEB)

The origin of natural gas in the Japanese oil and gas fields are geochemically studied. Samples are taken from structural natural gas, surface gas seepage, water-dissolved natural gas and coal-field gas of the Japan Sea coast area. The origins of primary hydrocarbons are classified into bacteria gas and thermogenic gas, the latter being subclassified into gas in oil production zone with the per million deviation of the carbon isotope (/sup 13/C/sup 1/) of methane less than -35 and those gases with maturity higher than this. Surface gas seepage is subjected to migration and bacterial oxidation. Coal gas is similar to oil gas. The CO/sub 2/ concentration is 0 - 2% and /sup 13/CO/sub 2/ deviations from -30 - +30. The origin can be barely estimated from the isotopic composition because of the wide secondary change in the composition. The origin and migration of gas from the gas field of northern Niigata are not similar to those in the southern area, which consist of a ...

1988-05-01

250

Effect of clindamycin treatment on vaginal inflammatory markers in pregnant women with bacterial vaginosis and a positive fetal fibronectin test  

British Library Electronic Table of Contents (United Kingdom)

Objective To compare the levels of interleukin (IL)-1?, IL-6, and matrix metalloproteinase (MMP)-8 in the vaginal secretions of pregnant women with a positive fetal fibronectin (fFN) test result with or without asymptomatic bacterial vaginosis (BV) before and after treatment with oral clindamycin. Methods A prospective cohort study was conducted among 43 pregnant women with a positive fFN test result. All patients were treated with clindamycin, and the pre- and post-treatment levels of IL-1?, IL-6, and MMP-8 were compared. Results Before treatment, levels of IL-1? and MMP-8 were significantly higher in women with BV compared with women without BV (P<0.05). Vaginal levels of IL-1? and IL-6, but not MMP-8, decreased after treatment in pregnant women with BV. Conclusions The inability of clin...

2009-01-01

251

Complete genome sequence of Conexibacter woesei type strain (ID131577T)  

Energy Technology Data Exchange (ETDEWEB)

The genus Conexibacter (Monciardini et al. 2003) represents the type genus of the family Conexibacteraceae (Stackebrandt 2005, emend. Zhi et al. 2009) with Conexibacter woesei as the type species of the genus. C. woesei is a representative of a deep evolutionary line of des-cent within the class Actinobacteria. Strain ID131577T was originally isolated from temperate forest soil in Gerenzano (Italy). Cells are small, short rods that are motile by peritrichous fla-gella. They may form aggregates after a longer period of growth and, then as a typical charac-teristic, an undulate structure is formed by self-aggregation of flagella with entangled bacteri-al cells. Here we describe the features of the organism, together with the complete sequence and annotation. The 6,359,369 bp long genome of C. woesei contains 5,950 protein-coding and 48 RNA genes and is part of the Genomic Encyclopedia of Bacteria and Archaea project.

2010-01-01

252

Use of the K88 antigen for in vivo bacterial competition with porcine strains of enteropathogenic Escherichia coli.  

Science.gov (United States)

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

1975-07-01

253

The wavelength dependence of ultraviolet enhanced reactivation in a mammalian cell-virus system  

International Nuclear Information System (INIS)

The effect of UV radiation in the wavelength region 230 nm to 302 nm on the ability of an irradiated mammalian cell to reactivate UV-irradiated mammalian virus was tested. An action spectrum for radiation enhanced reactivation (RER) is presented. The shape of the action spectrum points to a combined nucleic acid-protein target for UV radiation effects on this cellular parameter. An analysis of the results of others involving the biochemical and photobiological events involved in RER does not allow us to distinguish which macromolecule is the major contributor to this effect. Studies involving an analogous phenomenon in bacteris (Weigle reactivation) imply that RER and WR amy involve similar mechanisms. (author).

254

Mineral biotechnology. Microbial aspects of mineral beneficiation, metal extraction, and environmental control  

Energy Technology Data Exchange (ETDEWEB)

Papers in this book illustrate the utility of mineral biotechnology with respect to biobeneficiation, bioleaching, bioremediation and biomineralization. Papers of particular interest to the coal industry include: depression of pyrite flotation by yeast and bacteris (S.K. Kawatra and T.C. Eisele); desulfurization of coal by microbial flotation in a semicontinuous system (T. Nagaoka and others); biochemical removal of HAP precursors from coal - INEEL slurry column testing (K.S. Noah and G.J. Olson); microorganisms, biotechnology and acid rock drainage - emphasis on passive-biological control and treatment methods (N. Kuyucak); and utility of bioreagents in mineral processing (P. Somasundaran and others).

2001-07-01

255

Effect of microwaves on microorganisms in foods  

Energy Technology Data Exchange (ETDEWEB)

The microbial safety of foods cooked in microwave ovens was investigated. The mechanisms of microwave destruction of microorganisms were examined. Effects of time and temperature on microorganisms in different food systems were described. Studies showed that: microwave heating of food is more ''''food dependent'' than conventional heating; recommended microwave treatment time for some foods may not destroy high levels of bacteria; use of microwaves in combination with conventional heating methods results in more uniform heating of foods and destruction of bacteria; and microwaves exert different killing effects on individual bacterial species. (78 references, 2 tables)

1980-08-01

256

Dipyrone-induced changes in DNA repair and other cell membrane associated processes in Escherichia coli  

Energy Technology Data Exchange (ETDEWEB)

The analgesic, dipyrone (1,phenyl-2,3-dimethyl-5-pyrazolone-4-methylamino methane sulphonate sodium), at 20 mM concentration, inhibited the rejoining of single-strand scissions in DNA of Escherichia coli B/r cells induced by 20 krad gamma-radiation. The chemical altered the cell membrane structure as evidenced from the uptake of acriflavin, the efflux of potassium ions from the bacterial cells and the inhibition of alkaline phosphatase-a cell membrane associated enzyme. (author). 18 refs., 6 figures.

1982-09-01

257

Dipyrone-induced changes in DNA repair and other cell membrane associated processes in Escherichia coli  

International Nuclear Information System (INIS)

The analgesic, dipyrone (1,phenyl-2,3-dimethyl-5-pyrazolone-4-methylamino methane sulphonate sodium), at 20 mM concentration, inhibited the rejoining of single-strand scissions in DNA of Escherichia coli B/r cells induced by 20 krad gamma-radiation. The chemical altered the cell membrane structure as evidenced from the uptake of acriflavin, the efflux of potassium ions from the bacterial cells and the inhibition of alkaline phosphatase-a cell membrane associated enzyme. (author).

258

Characterisation of anti-Staphylococcus aureus activity of quercetin  

British Library Electronic Table of Contents (United Kingdom)

Summary Although many antibiotics are available for the treatment of bacterial infections, the emergence and global spread of antibiotic-resistant bacteria is a community-wide problem. To overcome this problem, we must explore alternative antimicrobials. This study investigated the antibacterial properties of quercetin, a flavonoid present in vegetables and fruits. Quercetin was tested against gram-positive and gram-negative bacteria and was found to exert selective antibacterial activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), and Staphylococcus epidermidis. Some clinical MRSA strains showed remarkable susceptibility to quercetin. In combination with antibiotics, such as oxacillin, ampicillin, vancomycin, gentamicin, and erythromycin, quercetin sho...

2010-01-01

259

X-ray absorption spectroscopy of bacterial sulfur globules  

Energy Technology Data Exchange (ETDEWEB)

Sulfur K-edge X-ray absorption spectroscopy is a powerful in situ probe of sulfur biochemistry in intact cells and tissues. Under favorable circumstances the technique can provide quantitative information on the chemical identify of the sulfur species that are present in a sample. Prange et al. have recently reported an X-ray absorption spectroscopic study of bacterial sulfur storage globules. Unfortunately there are substantial problems with the experimental technique employed that, they contend, lead to completely erroneous conclusions. In the more recent of their two papers Prange et al. employed a curve-fitting method similar to that used by us (for more than 10 years). In essence, the method employs simply fitting a linear combination of the spectra of standard compounds to that of the unknown, in this case cultures of bacterial cells. This type of analysis can provide quantitative estimates of the individual sulfur types in the sample, ...

2002-08-01

260

The association of asymptomatic bacterial vaginosis with upper genital tract infection.  

Science.gov (United States)

Objective: To determine whether asymptomatic bacterial vaginosis (BV) is associated with upper genital tract inflammation or bacterial colonization.Methods: Fifty nonpregnant women with intact uteri who planned to undergo gynecologic surgery and had no recent symptoms of vaginal infection were enrolled. We obtained a vaginal swab for Gram stain, endocervical swab for chlamydia and gonorrhea DNA probe testing, and Pipelle endometrial biopsy for aerobic and anaerobic cultures and histology. We correlated surgical findings and histology of available surgical specimens with the microbiologic results. The diagnosis of BV was made according to Speigel's criteria. Bacteria isolated from the uterus were classified as high virulence versus low virulence. Contingency tables were analyzed using the chi-square or Fisher Exact tests.Results: Twenty-one of 50 patients had BV on Gram stain, 3 had intermediate BV, and 3 had unreadable slides. Eleven patients ...

1998-07-01

261

Nonphotochemical Hole-Burning Studies of Energy Transfer Dynamics in Antenna Complexes of Photosynthetic Bacteria  

Energy Technology Data Exchange (ETDEWEB)

This thesis contains the candidate's original work on excitonic structure and energy transfer dynamics of two bacterial antenna complexes as studied using spectral hole-burning spectroscopy. The general introduction is divided into two chapters (1 and 2). Chapter 1 provides background material on photosynthesis and bacterial antenna complexes with emphasis on the two bacterial antenna systems related to the thesis research. Chapter 2 reviews the underlying principles and mechanism of persistent nonphotochemical hole-burning (NPHB) spectroscopy. Relevant energy transfer theories are also discussed. Chapters 3 and 4 are papers by the candidate that have been published. Chapter 3 describes the application of NPHB spectroscopy to the Fenna-Matthews-Olson (FMO) complex from the green sulfur bacterium Prosthecochloris aestuarii; emphasis is on determination of the low energy vibrational structure that is important for ...

2002-06-27

262

Isolation of imidacloprid degrading bacteria from industrial sites  

International Nuclear Information System (INIS)

Immidacloprid is a cyclodiene organochlorine used as an insecticide all over the world and possessing a serous environmental threat. It is mostly used for cotton insects (bollworm, aphid and white fly). For isolation of imidacloprid degrading bacteria, two soil samples were collected from industrial contaminated sites of Kala Shah Kahu district sheikupura, having ten year history of use. Soil samples were analyzed by measuring pH and electric conductivity. The isolation of imidacroprid degrading bacteria was performed by enrichment technique. Eight bacterial strains, S/sub 1-a/ S/2-2-b/ S/2-c/ S/2-d/ S/2-e/ S/sub 2-f/ and S/sub 2-g/ and S/sub e-a/ were isolated on the basis of their colony morphologies. The purified colonies were characterized morphologically, physiologically and biochemically. Gram staining was done and Gram negative strain were confirmed on MacConkey agar and Eosin Methylene Blue. Bacterial strains were also checked for ...

263

Bacterial radiosensitization by using radiation processing in combination with essential oil: Mechanism of action  

Energy Technology Data Exchange (ETDEWEB)

Spice extracts under the form of essential oils were tested for their efficiency to increase the relative radiosensitivity of Listeria monocytogenes and Escherichia coli O157H7 in culture media. The two pathogens were treated by gamma-irradiation alone or in combination with oregano essential oil to evaluate their mechanism of action. The membrane murein composition, and the intracellular and extracellular concentration of ATP was determined. The bacterial strains were treated with two irradiation doses: 1.2 kGy to induce cell damage and 3.5 kGy to cause cell death for L. monocytogenes. A dose of 0.4 kGy to induce cell damages, 1.1 kGy to obtain viable but nonculturable (VBNC) state and 1.3 kGy to obtain a lethal dose was also applied on E. coli O157H7. Oregano essential oil was used at 0.020% and 0.025% (w/v), which is the minimum inhibitory concentration (MIC) for L. monocytogenes. For E. coli O157H7, a concentration of 0.006% and 0.025% (w/v) which is the ...

2009-07-15

264

The effects of surface damage on RF cavity operation  

Energy Technology Data Exchange (ETDEWEB)

We describe a model of damage in rf cavities and show how this damage can limit cavity operation. We first present a review of mechanisms that may or may not affect the ultimate fields that can be obtained in rf cavities, assuming that mechanical stress explains the triggers of rf breakdown events. We present a method of quantifying the surface damage caused by breakdown events in terms of the spectrum of field enhancement factors, Beta, for asperities on the surface. We then model an equilibrium that can develop between damage and conditioning effects, and show how this equilibrium can determine cavity performance and show experimental evidence for this mechanism. We define three functions that quantify damage, and explain how the parameters that determine this performance can be factored out and measured. We then show how this model can quantitatively explain the dependence of cavity performance on material, frequency, pulse length, gas, ...

2006-04-14

265

The effect of welding parameters on hydrogen distribution in pipeline welds  

Energy Technology Data Exchange (ETDEWEB)

There is currently considerable interest in identifying and quantifying the effects of welding procedure parameters and steel composition factors on the risk of cracking in pipeline girth welds that may be experienced during winter construction. Although low ambient temperatures, that may be experienced during winter construction, are generally assumed to increase the risk of cracking there has been little work to quantify the effects and to suggest how welding procedures should be modified for winter conditions. The present work was undertaken to calculate the effects of changes in welding parameters on the thermal cycle and the diffusion of hydrogen for a typical pipeline girth weld. A simple analytical method and the finite element method (FEM) were used. Both methods gave similar results but the simple method was very sensitive to the value of heat transfer coefficient. The results showed that the relation between the hydrogen diffusion ...

1990-03-01

266

The Effects of Exurbanization on Bird and Macro invertebrate Communities in Deciduous Forests on the Cumberland Plateau, Tennessee  

International Nuclear Information System (INIS)

To investigate the potential causes of changes to bird communities in exurban areas, we examined the relationship between bird and macro invertebrate communities in exurbanized forest. We randomly located sampling points across a gradient of exurbanization. We used point counts to quantify bird communities and sweep netting, soil cores, pitfalls, and frass collectors to quantify macro invertebrates. Bird communities had higher richness and abundance in exurban areas compared to undeveloped forests, and lost some species of conservation concern but gained others. The macro invertebrate community was slightly more abundant in exurban areas, with a slight shift in taxonomic composition. The abundance of macro invertebrates in soil cores (but not pitfalls) predicted the abundance of ground-foraging birds. The abundance of macro invertebrates in sweep nets was not associated with the abundance of aerial insectivore birds. Exurbanization therefore ...

267

Second-law efficiency of solar-thermal cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

Properly quantified performance of a solar-thermal cavity receiver must not only account for the energy gains and losses as dictated by the First Law of thermodynamics, but it must also account for the quality of that energy. However, energy quality can only be determined from the Second Law. In this paper an equation for the Second-Law efficiency of a cavity receiver is derived from the definition of available energy or availability (occassionally called exergy), which is a thermodynamic property that measures the maximum amount of work obtainable when a system is allowed to come into unrestrained equilibrium with the surrounding environment. The fundamental concepts of the entropy and availability of radiation are explored from which a convenient relationship among the reflected cone half angle, the insolation, and the concentrator geometric characteristics is developed as part of the derivation of the Second-Law efficiency. A comparison is made between First- ...

1983-10-01

268

Quantification of the local glucose utilization and local blood flow in the heart of the awake rat using the /sup 14/C-2-deoxyglucose and /sup 14/C-iodoantipyrine methods  

Science.gov (United States)

Local cardiac glucose utilization (LCarGU) was quantified in the rat heart according to the Sokoloff model and local cardiac blood flow (LCarBF) according to the /sup 14/C-iodoantipyrine method. For quantitative autoradiography calibration curves for heart slices were performed. They differed from the brain calibration curves by 8%. The lumped constant was 0.377 in isolated working hearts. LCarGU and LCarBF could then be quantified in awake rats. At different locations mean LCarGU of different hearts varied from 85 to 200 ..mu..moles/100g/min and mean LCarBF from 390 to 831 ml/100g/min. The ratio subendocardial/subepicardial glucose utilization or blood flow was not systematically different from 1. The results indicate that glucose can be an important fuel in the heart of the awake rat, although its contribution to overall metabolism varies from animal to animal.

1986-03-05

269

Data report of BWR post-CHF tests. Transient core thermal-hydraulic test program. Contract research  

Energy Technology Data Exchange (ETDEWEB)

JAERI has been performing transient core thermal-hydraulic test program. In the program, authors performed BWR/ABWR DBE simulation tests with a test facility, which can simulate BWR/ABWR transients. The test facility has a 4 x 4 bundle core simulator with 15-rod heaters and one non-heated rod. Through the tests, authors quantified the thermal safety margin for core cooling. In order to quantify the thermal safety margin, authors collected experimental data on post-CHF. The data are essential for the evaluation of clad temperature transient when core heat-up occurs during DBEs. In comparison with previous post-CHF tests, present experiments were performed in much wider experimental condition, covering high clad temperature, low to high pressure and low to high mass flux. Further, data at wider elevation (lower to higher elevation of core) were obtained in the present experiments, which make possible to discuss the effect of axial position on ...

2001-03-01

270

An objective indicator for two-phase flow pattern transition  

Energy Technology Data Exchange (ETDEWEB)

This work concerns the development of a methodology the objective of which is to characterize and diagnose two-phase flow regime transitions. The approach is based on the fundamental assumption that a transition flow is less stationary than a flow with an established regime. During the first time, the efforts focused on: (1) the design and construction of an experimental loop, allowing to reproduce the main horizontal two-phase flow patterns, in a stable and controlled way; (2) the design and construction of an electrical impedance probe, providing an imaged information of the spatial phase distribution in the pipe; and (3) the systematic study of the joint time-frequency and time-scale analysis methods, which permitted to define an adequate parameter quantifying the unstationarity degree. During the second time, in order to verify the fundamental assumption, a series of experiments were conducted, the objective of which was to demonstrate the correlation between ...

1998-08-01

271

An objective indicator for two-phase flow pattern transition  

International Nuclear Information System (INIS)

This work concerns the development of a methodology the objective of which is to characterize and diagnose two-phase flow regime transitions. The approach is based on the fundamental assumption that a transition flow is less stationary than a flow with an established regime. During the first time, the efforts focused on: (1) the design and construction of an experimental loop, allowing to reproduce the main horizontal two-phase flow patterns, in a stable and controlled way; (2) the design and construction of an electrical impedance probe, providing an imaged information of the spatial phase distribution in the pipe; and (3) the systematic study of the joint time-frequency and time-scale analysis methods, which permitted to define an adequate parameter quantifying the unstationarity degree. During the second time, in order to verify the fundamental assumption, a series of experiments were conducted, the objective of which was to demonstrate the correlation between ...

1998-08-01

272

A new method for quantifiable and controlled dosage of particulate matter for in vitro studies: the electrostatic particulate dosage and exposure system (EPDExS).  

Science.gov (United States)

An exposure chamber is described for the quantifiable addition of fine and ultrafine aerosol particulate matter directly to cells and used to demonstrate the in vitro cytotoxicity of fine 1,4-naphthoquinone particles to murine lung epithelial cells. The electrostatic particulate dosage and exposure system (EPDExS) operates on the principle of electrostatic precipitation and is shown to deposit fine and ultrafine aerosol particles directly to cells with 100% efficiency for particle diameters in the range of 40-530nm. This range is not limited by the EPDExS, but rather by the aerosolization method used for this study. Numbers of particles deposited onto the cells are counted with a condensation particle counter, negating any need to calculate or estimate particle exposure. The process of particle introduction, assessed using Trypan blue dye exclusion, had no effect on cell viability. In combination with a differential mobility classifier, the EPDExS can deliver ...

2008-06-08

273

A carbon monoxide passive sampler: Research and development needs  

Energy Technology Data Exchange (ETDEWEB)

In rare instances, carbon monoxide (CO) levels in houses can reach dangerously high concentrations, causing adverse health effects ranging from mild headaches to, under extreme conditions, death. Hundreds of fatal accidental carbon monoxide poisonings occur each year primarily due to the indoor operation of motor vehicles, the indoor use of charcoal for cooking, the operation of malfunctioning vented and unvented combustion appliances, and the misuse combustion appliances. Because there is a lack of simple, inexpensive, and accurate field sampling instrumentation, it is difficult for gas utilities and researchers to conduct field research studies designed to quantify the concentrations of CO in residences. Determining the concentration of CO in residences is the first step towards identifying the high risk appliances and high-CO environments which pose health risks. Thus, there exists an urgent need to develop and field-validate a ...

1991-11-01

274

Visible and near-infrared spectral signatures for adulteration assessment of extra virgin olive oil  

Science.gov (United States)

Because of its high price, the extra virgin olive oil is frequently target for adulteration with lower quality oils. This paper presents an innovative optical technique capable of quantifying the adulteration of extra virgin olive oil caused by lowergrade olive oils. It relies on spectral fingerprinting the test liquid by means of diffuse-light absorption spectroscopy carried out by optical fiber technology in the wide 400-1700 nm spectral range. Then, a smart multivariate processing of spectroscopic data is applied for immediate prediction of adulterant concentration.

2010-04-01

275

Use of activated charcoal for the purification of neon in the CLEAN experiment  

Energy Technology Data Exchange (ETDEWEB)

Passage of neon gas through activated charcoal is planned to be the primary method of removing impurities from the liquid neon scintillator in the CLEAN experiment. In order to quantify this technique, the breakout curves for hydrogen, nitrogen, argon and krypton impurities in neon-saturated activated charcoal were measured. Adsorption coefficients and the number of theoretical stages were measured for hydrogen in the temperature range between 300 and 80 K, nitrogen between 300 and 200 K, and argon between 300 and 190 K. The adsorption coefficient for krypton was measured at 300 K.

2007-01-21

276

Upgraded coal interest group. Quarterly report, July 1, 1995--September 30, 1995  

Energy Technology Data Exchange (ETDEWEB)

The objectives of the Upgraded Coal Interest Group (UCIG) are as follows: Review and update the status of various coal upgrading technologies and developments and critically assess the results. Perform engineering screening analyses on various coal upgrading approaches. Perform commercialization analyses that will promote the availability and use of upgraded coal products by quantifying the benefits of using them. Identify market opportunities for introduction of upgraded coals. Perform critical analyses on a variety of coals and technologies in areas important to users but not readily available. Perform critical experiments which will show the differences between technologies.

1995-12-31

277

Towards an understanding of the light scalar mesons  

Energy Technology Data Exchange (ETDEWEB)

Although studied for many years the nature of the light scalar mesons remains controversial. Here we shall present a method, applicable for s-wave states located close to a threshold, that allows one to quantify the molecular part of a given state. When applied to the f{sub 0}(980) a dominance of the molecular component is found. In the second part, we show that requirements of field-theoretic consistency and chiral symmetry, when applied to the scattering of light pseudo-scalars, naturally lead to the appearance of dynamical poles in the scalar sector. A program is proposed on how to further investigate experimentally the mixing between these dynamical states and possible genuine quark states. (orig.)

2007-03-15

278

The new thermal comfort equation to qualify air in buildings. De nieuwe behaaglijkheidsbalans voor de kwaliteit van de lucht in gebouwen  

Energy Technology Data Exchange (ETDEWEB)

In the 1988 February issue of this magazine the units olf and decipol were introduced. Olf is a measure for the pollution load and decipol for the indoor air quality. This article discusses a new ventilation theory which is quantified by the new indoor air quality thermal comfort balance based on the units olf and decipol. This balance requires more ventilation air than for the present regulations. It takes into account all pollution sources. 2 figs., 9 refs., 3 tabs.

1990-05-01

279

Solid-state ozone synthesis by energetic ions  

International Nuclear Information System (INIS)

We have synthesized ozone by irradiating thin solid films of oxygen and oxygen-water mixtures with 100 keV protons, motivated by recent reports of condensed O_3 on icy satellites in the outer Solar system. We measured the depth of the Hartley absorption band in the ultraviolet by reflectance spectroscopy and used it to quantify the column density of ozone. We analyzed the results using a three-component (O, O_2 and O_3) model that successfully explains the fluence dependence of ozone production.

1999-08-02

280

Radiation risk in diagnostic radiology  

International Nuclear Information System (INIS)

An attempt was made to quantify the radiation risk of diagnostic radiology. After a general introduction of terms as radiation damage, radiation risk and effective dose equivalent, based on publications of the ICRP, somatic dose indexes were computed for several radiologic investigations, that comprise organ doses committed to red bone marrow, lung, female breast and thyroid with and without considering the rest of the body. The dose for the rest of the body was assumed to be equal to the dose received by the red bone marrow, that is also distributed over the whole body. Neglecting the exposure of the rest of the body resulted in an insignificant increase in the estimated somatic risk, with its experimental determination not being necessary. (author).

1984-01-01

281

Quantification of uranium transport away from firing sites at Los Alamos National Laboratory: A mass balance approach  

Science.gov (United States)

Investigations were conducted at Los Alamos National Laboratory to quantify the extent of migration of depleted uranium away from firing sites. Extensive sampling of air particles, soil, sediment, and water was conducted to establish the magnitude of uranium contamination throughout one watershed. The uranium source term was estimated, and mass balance calculations were performed to compare the percentage of migrated uranium with original expenditures. Mass balance calculations can be powerful in identification of the extent of waste migration and used as an aid in planning future waste investigations.

1992-02-01

282

Low-level and transuranic waste transportation, disposal, and facility decommissioning cost sensitivity analysis  

Energy Technology Data Exchange (ETDEWEB)

The Systems Design Study (SDS) identified technologies available for the remediation of low-level and transuranic waste stored at the Radioactive Waste Management Complex's Subsurface Disposal Area at the Idaho National Engineering Laboratory. The SDS study intentionally omitted the costs of transportation and disposal of the processed waste and the cost of decommissioning the processing facility. This report provides a follow-on analysis of the SDS to explore the basis for life-cycle cost segments of transportation, disposal, and facility decommissioning; to determine the sensitivity of the cost segments; and to quantify the life-cycle costs of the 10 ex situ concepts of the Systems Design Study.

1992-05-01

283

Low-level and transuranic waste transportation, disposal, and facility decommissioning cost sensitivity analysis  

Energy Technology Data Exchange (ETDEWEB)

The Systems Design Study (SDS) identified technologies available for the remediation of low-level and transuranic waste stored at the Radioactive Waste Management Complex`s Subsurface Disposal Area at the Idaho National Engineering Laboratory. The SDS study intentionally omitted the costs of transportation and disposal of the processed waste and the cost of decommissioning the processing facility. This report provides a follow-on analysis of the SDS to explore the basis for life-cycle cost segments of transportation, disposal, and facility decommissioning; to determine the sensitivity of the cost segments; and to quantify the life-cycle costs of the 10 ex situ concepts of the Systems Design Study.

1992-05-01

284

Intergranular corrosion of Alloy 800 by the electrochemical potentiokinetic reactivation method  

Energy Technology Data Exchange (ETDEWEB)

The 'Electrochemical Potentiokinetic Reactivation' method has been employed to quantify the degree of intergranular corrosion of Alloy 800, with different Ti + Al content, aged in the range 500-650/sup 0/C for times up to 5000 hours. The results were compared with the classical Rollason's curves obtained by means of the Strauss' test and a satisfactory agreement was found. An explanation of the slight differences between both methods has been proposed on the basis of the passivity film morphology.

1981-08-01

285

Hideout return testing from support crevices  

International Nuclear Information System (INIS)

The objectives of the project were to develop operational techniques for promoting contaminant hideout return from tube support crevices and to identify the effect of chemical inhibitor application on corrodent transport. The implementation of routine procedures for promoting the return of sequestered corrodents could retard the progression of denting or other corrosion processes and improve steam generator availability. Tests also quantified the effect of inhibitor application on crevice hideout and hideout return processes, with the intention of developing a better understanding of the inhibition mechanism. By carefully monitoring the hideout and hideout return inventories, the program also has provided the opportunity to study steam generator concentration processes in general.

1985-03-01

286

Experimental Uncertainty for the Thermal Expansion of a Simulated Fuel  

Energy Technology Data Exchange (ETDEWEB)

Thermal expansions of a simulated fuel (SS-1) were measured by using a Dilatometer (DIL402C) from room temperature to 1900 K. The main procedure of an uncertainty evaluation followed the strategy of the UO{sub 2} fuel. Referring to the ISO (International Organization for Standardization) guide, the uncertainties of the thermal expansion were quantified in three parts - the initial length, the length variation, and the system calibration factor. The uncertainty of the thermal expansion for a simulated fuel was also compared with those of UO{sub 2} fuel.

2006-07-01

287

Entangled quantum currents in distant mesoscopic Josephson junctions  

Energy Technology Data Exchange (ETDEWEB)

Two mesoscopic SQUID rings which are far from each other are considered. A source of two-mode nonclassical microwaves irradiates the two rings with correlated photons. The Josephson currents are in this case quantum mechanical operators, and their expectation values with respect to the density matrix of the microwaves yield the experimentally observed currents. Classically correlated (separable) and quantum mechanically correlated (entangled) microwaves are considered, and their effect on the Josephson currents is quantified. Results for two different examples that involve microwaves in number states and coherent states are derived. It is shown that the quantum statistics of the tunnelling electron pairs through the Josephson junctions in the two rings are correlated.

2004-12-22

288

Electron Beam and Gamma Radiolysis of Solid-State Metoclopramide  

British Library Electronic Table of Contents (United Kingdom)

Purpose Study the radiolysis of solid-state metoclopramide hydrochloride at various absorbed doses. Elucidate the structure of the degradation products to gain information on the radiolysis mechanisms. Methods Solid-state metoclopramide samples were irradiated at several doses with gamma rays and high-energy electrons to evaluate the influence of the dose rate. High-performance liquid chromatography with a diode array detector was used to measure the chemical potency as a function of the absorbed dose and to quantify the degradation products. The characterization of degradation products was performed by liquid chromatography/atmospheric pressure chemical ionization/tandem mass spectrometry. Results The degradation of solid-state metoclopramide after irradiation was negligible. No qualitati...

2006-01-01

289

Comparison of the TESLA, NLC and CLIC Beam-Collimation System Performance  

CERN Document Server

This report describes studies performed in the framework of the Collimation Task Force organized to support the work of the second International Linear Collider Technical Review Committee. The post-linac beam-collimation systems in the TESLA, JLC/NLC and CLIC linear-collider designs are compared using the same computer code under the same assumptions. Their performance is quantified in terms of beam-halo and synchrotron-radiation collimation efficiency. The performance of the current designs varies across projects, and does not always meet the original design goals. But these comparisons suggest that achieving the required performance in a future linear collider is feasible.

2004-01-01

290

Commercial Credit Value Evaluation and Illustration Analysis on Internet  

Science.gov (United States)

Taobao website online transaction evaluation has been well accepted, but its value has not been measured. This paper quantifies the value of commercial credit of salers in bringing sale purchase on Taobao website through three aspects of data as credit score buyer to saler, number of comments and rate of bad comments. The illustration results on Taobao online transaction credit evaluation show that number of comments, credit score and rate of bad comments have significant impact on sale revenue.

2011-01-01

291

Climate change - the contribution from air travel  

International Nuclear Information System (INIS)

The paper discusses the Intergovernment Panel on Climate Change (IPCC) report on Aviation and the Global Atmosphere (published in 1999). It was considered necessary to treat air transport on its own since aircraft are unique in delivering emissions into the upper atmosphere rather than at ground level. The study was commissioned at the request of the International Civil Aviation Organisation and the Montreal Protocol. More than 300 experts contributed and the report has quantified the effect of aviation on the atmosphere on a world wide basis and highlighted areas where improved data are required. (UK)

2000-04-01

292

Characterization of Mixed Wettability at Different Scales and its Impact on Oil Recovery Efficiency  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this project was to: (1) quantify the pore scale mechanisms that determine the wettability state of a reservoir, (2) study the effect of crude oil, brine and mineral compositions in the establishment of mixed wet states, (3) clarify the effect of mixed - wettability on oil displacement efficiency in waterfloods, (4) develop a new tracer technique to measure wettability, fluid distributions, residual saturation's and relative permeabilities, and (5) develop methods for properly incorporating wettability in up-scaling from pore to core to reservoir scales.

2002-01-28

293

Chandler Slavin | Greener Package  

Wastenet

...it only highlights the different feedstocks used in the production of fiber-based packaging materials or fossil-fuel ones; what about the energy required to convert ...feedstock, is unacceptable in trying to quantify the overall burden a specific packaging material has on the environment. As an aside, the point ... Consequentially, it is difficult to speculate on how much packaging material a company diverts from the landfill by switching from one material to another ...without specifying what geographical region said packaging material resides in. In addition, there is a lot of interest in diverting PET thermoforms from ...

294

AFS Cupola Model Verification--Initial Investigations  

Science.gov (United States)

The cupola furnace is used to melt scrap steel, pig iron, foundry returns, and alloying additives to a prescribed tapping chemistry and temperature for iron casting applications. The melting process within the cupola is highly complex and not well quantified. The American Foundrymen's Society is developing a mathematical model to aid in the understanding of these processes. This model is reaching maturity, and has been successful in estimating a number of melting parameters. This paper details the results of efforts to verify the model in a controlled system, equipped wit the appropriate sensors, for model verification. The work was performed on a research-scale cupola furnace located at the Department of Energy's Albany Research Center.

1998-01-01

295

A quantitative method to detect explosives and selected semivolatiles in soil samples by Fourier transform infrared spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a novel Fourier transform infrared (FTIR) spectroscopic method that can be used to rapidly screen soil samples from potentially hazardous waste sites. Samples are heated in a thermal desorption unit and the resultant vapors are collected and analyzed in a long-path gas cell mounted in a FTIR. Laboratory analysis of a soil sample by FTIR takes approximately 10 minutes. This method has been developed to identify and quantify microgram concentrations of explosives in soil samples and is directly applicable to the detection of selected volatile organics, semivolatile organics, and pesticides.

1995-06-01

296

A mathematical model for simulating shallow solar ponds for treatment of industrial wastewater  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a mathematical model to analyze the solar evaporation in a shallow pond in steady state, when the inlet flow rate, concentration, surface area and solar radiation are given. The simultaneous heat and mass transfer mechanisms are considered for quantifying the amount of evaporated water to the atmosphere and the actual absorbed heat by wastewater is calculated to obtain the bottom temperature of water pond. The heat losses to air by radiation and convection mechanisms are considered and the heat transmission across the water film is evaluated by the forced convection mechanism. 6 refs., 5 figs., 1 tab.

1996-12-31

297

A Virtual Young's Double Slit Experiment for Hard X-ray Photons  

CERN Document Server

We have implemented a virtual Young's double slit experiment for hard X-ray photons with micro-fabricated bi-prisms. We observe fringe patterns with a scintillator, and quantify interferograms by detecting X-ray fluorescence from a scanned 30nm Cr metal film. The observed intensities are best modeled with a near-field, Fresnel analysis. The maximum fringe number in the overlap region is proportional to the ratio of real to imaginary parts refractive index of the prism material. The horizontal and vertical transverse coherence lengths at beamline APS 8-ID are measured.

2009-01-01

298

Spent fuel sabotage aerosol ratio program : FY 2004 test and data summary  

International Nuclear Information System (INIS)

This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. The program also provides significant technical and political benefits in international cooperation. We are quantifying the Spent Fuel Ratio (SFR), the ratio of the aerosol particles released from HEDD-impacted actual spent fuel to the aerosol particles produced from surrogate materials, measured under closely matched test conditions, in a contained test chamber. In addition, we are measuring the amounts, nuclide content, size distribution of the ...

299

Quantifying regenerator thermal shorting; Bestimmung des thermischen Kurzschlusses von Regeneratorgeweben  

Energy Technology Data Exchange (ETDEWEB)

The regenerator of Stirling cycle machines has an relatively unknown potential for thermal shorting, because the thermal flow path within the solid of a randomly stacked wire mesh, which is defined by its 'connectivity', is unknown. Earlier publications have shown two principles of experimental techniques to quantify connectivity. One quantifies connectivity as a function of axial pressure using the electric current analogy, the other measures connectivity via the temperature gradients along a regenerator and a series-connected reference body of known conductivity. Both papers offer preliminary results of reduced usefulness related to the testing method or setup. This contribution describes a new setup and its technique, which results from the practical knowledge and experience of the first two attempts, and aims for an improved determination of connectivity of the original representative Stirling regenerators with and without ...

2000-07-01

300

Hydration of swelling clay and bacteria interaction. An experimental in situ reaction study; Hydratation des argiles gonflantes et influence des bacteries. Etude experimentale de reaction in situ  

Energy Technology Data Exchange (ETDEWEB)

This study reports on the physical-chemical behaviour of swelling di-octahedral clays (smectites) and their interaction with aqueous solutions and bacteria (Shewanella putrefaciens). Experimental results are presented for compacted clays, hydrated under confined volume conditions, using a new type of reaction-cell (the 'wet-cell' of Warr and Hoffman, 2004) that was designed for in situ X-ray diffraction (XRD) measurement. For comparison, dispersed clay systems were studied using standard batch solutions subjected to varying degrees of agitation. The combination of time-dependent in situ XRD measurements with gravimetric measurements and calculated diffraction patterns using the CALCMIX software (Plancon and Drits, 1999) allowed to successful quantification of the dynamics of water uptake and storage. This analytical procedure combined with published water vapour adsorption data enabled determination of the abundance of structured water layers, developed in the ...

2008-01-15

301

[Study on denitrification characteristics of dynamic membrane based on nitrate liquid-membrane microelectrodes].  

Science.gov (United States)

Nitrate microelectrodes and ORP microelectrodes were fabricated to study the denitrification characteristics of dynamic membrane at different COD loadings. The denitrification process was found at 0.6-1 mm depth beneath the interface of biofilm/bulk. The results of ORP microelectrode also demonstrated that the ORP value in the range of denitrification area was between 88.6 approximately -128.4 mV which was appropriate to denitrification. When the COD loading was 0.45 kg/(m3 x d), the denitrification rate (NO3- -N) was the maximum of 0.6347 x 10(-6 mol/(L x s). With the increase of COD loading, the denitrification area was increasing and two layers with different denitrification rates emerged in the dynamic membrane. The phenomenon implied the effect of organic concentration, oxygen concentration and bacterial competition on the denitrification rate. PMID:17117632

2006-09-01

302

[Dysspermia due to inflammation. The evaluation of sperm cultures].  

Science.gov (United States)

The study evaluates 160 cases of positive spermioculture taken from 522 sterile individuals examined by the authors at the Couple Sterility Outpatient unit in Department A of the Institute of Gynecology and Obstetrics at Turin University during the period between January 1984 and December 1993. The germs responsible for infection were assayed in order to evaluate the strains which showed the highest incidence every year. Whereas there was no significant change in the absolute number of cases of sterility over the period, the number of cases caused by infection increased significantly during the second five-year period. It was found that the germs predominantly implicated in the genesis of male sterility formed part of the so-called mixed flora group, responsible in women for syndromes of often asymptomatic bacterial vaginosis which are not identified and consequently not treated. PMID:8559444

303

Use of flow cytometry to compare the antimicrobial efficacy of silver-containing wound dressings against planktonic Staphylococcus aureus and Pseudomonas aeruginosa  

British Library Electronic Table of Contents (United Kingdom)

Abstract Silver-impregnated wound dressings continue to be routinely used for the management of infected wounds, or wounds that are at risk of becoming infected. The ability of antimicrobials that have been incorporated into wound dressings to kill microorganisms within the dressing requires appropriate evaluation using in vitro models. In vitro models that have been exploited for this purpose have included the corrected zone of inhibition and the log reduction assay. However, these and other related culturable-based assays are purported to have poor correlation with the overall microbicidal barrier activity of an antimicrobial wound dressing. This is because culturable-based methods only retrospectively indicate bacterial cell death and do not take into account viable but nonculturable st...

2011-01-01

304

The type III secretion system is involved in Escherichia coli K1 interactions with Acanthamoeba  

British Library Electronic Table of Contents (United Kingdom)

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...

2011-01-01

305

The influence of ultrasound on the fluoroquinolones antibacterial activity  

British Library Electronic Table of Contents (United Kingdom)

In this work, the antibacterial effect of fluoroquinolones (FQs) upon Escherichia coli (E.coli) was measured with and without application of 40kHz ultrasound (US) stimulation. The research results demonstrated that simultaneous application of 40kHz US apparently enhanced the antibacterial effectiveness of FQs. That is, the synergistic effect was observed and the bacterial viability was reduced when FQs and US were combined. In addition, various influencing factors, such as FQs drug concentration, US irradiation time and solution temperature, on the inhibition of E.coli were also investigated. The antibacterial activity was enhanced apparently with increasing of FQs drug concentration, US irradiation time and solution temperature. Furthermore, we discussed preliminarily the mechanism of US ...

2011-01-01

306

The expression profile of TLR9 mRNA and CpG ODNs immunostimulatory actions in the teleost gilthead seabream points to a major role of lymphocytes  

British Library Electronic Table of Contents (United Kingdom)

Abstract. The potential effects of synthetic unmethylated oligodeoxynucleotides (ODN) containing CpG motifs, mimicking bacterial DNA, has never been evaluated on the immune response in the teleost fish gilthead seabream (Sparus aurata), the most important fish species in Mediterranean aquaculture. First, binding and competition studies have demonstrated that binding is saturated and promiscuous, suggesting the participation of several receptors. Moreover, leucocyte cytotoxic (NCC) activity, production of ROIs (reactive oxygen intermediates), and expression of immune-relevant genes was greatly primed by ODNs. Focusing on the mechanism, the TLR9 gene is widely distributed in seabream tissues and differently regulated in vitro by several stimuli. Moreover, and for the first time in fish, TLR9...

2008-01-01

307

Synthesis, Characterization and Biological Properties of Anions of Bivalent Transition Metal [Co(II) and Ni(II)] Complexes With Acylhydrazine Derived ONO Donor Schiff Bases.  

Science.gov (United States)

Some acylhydrazine derived ONO donor Schiff bases and their Co(II) and Ni(II) complexes have been prepared having the same metal ion (cation) but different anions. These synthesized metal(II) complexes have been characterized on the basis of their elemental analyses, magnetic moment, molar conductance, and IR and electronic spectral data. All of the Schiff base ligands function as tridentates and the deprotonated enolic form is preferred for coordination. In order to evaluate the effect of anions on the bactericidal activity, these synthesized complexes, in comparison to the uncomplexed Schiff bases have been screened against bacterial species., Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and the results are reported. PMID:18475936

2000-01-01

308

Sodium-driven motor of the polar flagellum in marine bacteria Vibrio  

British Library Electronic Table of Contents (United Kingdom)

The Na+-driven bacterial flagellar motor is a molecular machine powered by an electrochemical potential gradient of sodium ions across the cytoplasmic membrane. The marine bacterium Vibrio alginolyticus has a single polar flagellum that enables it to swim in liquid. The flagellar motor contains a basal body and a stator complexes, which are composed of several proteins. PomA, PomB, MotX, and MotY are thought to be essential components of the stator that are required to generate the torque of the rotation. Several mutations have been investigated to understand the characteristics and function of the ion channel in the stator and the mechanism of its assembly around the rotor to complete the motor. In this review, we summarize recent results of the Na+-driven motor in the polar flagellum of ...

2011-01-01

309

Root Hairs Play a Key Role in the Endophytic Colonization of Olive Roots by Pseudomonas spp. with Biocontrol Activity  

British Library Electronic Table of Contents (United Kingdom)

The use of indigenous bacterial root endophytes with biocontrol activity against soil-borne phytopathogens is an environmentally-friendly and ecologically-efficient action within an integrated disease management framework. The earliest steps of olive root colonization by Pseudomonas fluorescens PICF7 and Pseudomonas putida PICP2, effective biocontrol agents (BCAs) against Verticillium wilt of olive (Olea europaea L.) caused by the fungus Verticillium dahliae Kleb., are here described. A gnotobiotic study system using in vitro propagated olive plants, differential fluorescent-protein tagging of bacteria, and confocal laser scanning microscopy analysis have been successfully used to examine olive roots?Pseudomonas spp. interactions at the single-cell level. In vivo simultaneous visualization...

2011-01-01

310

R46 and pKM101 plasmid-mediated resistance to ionizing radiation in Escherichia coli  

International Nuclear Information System (INIS)

The ability of the R46 R factor and its derivative pKM101 to modify sensitivity to "6"0Co #gamma# radiation was studied. In Escherichia coli K12 both plasmids enhanced bacterial survival after "6"0Co #gamma# irradiation. This effect was dependent on recA"+ genotype but not on recB"+, recB"+recC"+, and recF"+ genotypes. 5-Fluorouracil eliminated the R46 R factor from the parent and its rec"- mutant strains. These strains lost not only the antibiotic resistance coded for R46 R factor but their radioresistance as well.

311

Practical applications and feasibility of efflux pump inhibitors in the clinic-A vision for applied use  

British Library Electronic Table of Contents (United Kingdom)

The world of antibiotic drug discovery and development is driven by the necessity to overcome antibiotic resistance in common Gram-positive and Gram-negative pathogens. However, the lack of Gram-negative activity among both recently approved antibiotics and compounds in the developmental pipeline is a general trend despite the fact that the plethora of covered drug targets are well-conserved across the bacterial kingdom. Such intrinsic resistance in Gram-negative bacteria is largely attributed to the activity of multidrug resistance (MDR) efflux pumps. Moreover, these pumps also play a significant role in acquired clinical resistance. Together, these considerations make efflux pumps attractive targets for inhibition in that the resultant efflux pump inhibitor (EPI)/antibiotic combination d...

2006-01-01

312

Novel Techniques and Their Wide Applications to Health Foods, Medical and Agricultural Biotechnology in Relation to Policy Making on Genetically Modified Crops and Foods  

CERN Document Server

Selected applications of novel techniques in Agricultural Biotechnology, Health Food formulations and Medical Biotechnology are being reviewed with the aim of unraveling future developments and policy changes that are likely to open new markets for Biotechnology and prevent the shrinking or closing of existing ones. Amongst the selected novel techniques with applications in both Agricultural and Medical Biotechnology are: immobilized bacterial cells and enzymes, microencapsulation and liposome production, genetic manipulation of microorganisms, development of novel vaccines from plants, epigenomics of mammalian cells and organisms, and biocomputational tools for molecular modeling related to disease and Bioinformatics. Both fundamental and applied aspects of the emerging new techniques are being discussed in relation to their anticipated, marked impact on future markets and present policy changes that are needed for success in either Agricultural or Medical ...

2004-01-01

313

Non-toxigenic Clostridium sordellii: Clinical and microbiological features of a case of cholangitis-associated bacteremia  

British Library Electronic Table of Contents (United Kingdom)

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...

2011-01-01

314

N-acetoxy-N-2-acetylaminofluorene induced frameshift mutations: a comparison between the DNA modification spectrum and the mutation spectrum  

International Nuclear Information System (INIS)

We describe the analysis of forward mutations induced in the tetracycline resistance gene of the plasmid pBR322 by directing the reaction of the carcinogen N-acetoxy-N-2-acetylaminofluorene (N-AcO-AAF) to a small restriction fragment (BamHI, SalI) that is located in the proximal part of the antibiotic-resistance gene. Mutant plasmids obtained both in wild type and excision repair deficient (uvrA) bacterial cells are compared. Preliminary data showing the distribution of the -AAF adducts along this restriction fragments are discussed in relation to the observed spectrum of mutations. 20 references, 4 figures.

315

Mitochondrial NADH:ubiquinone oxidoreductase (complex I) in eukaryotes: A highly conserved subunit composition highlighted by mining of protein databases  

British Library Electronic Table of Contents (United Kingdom)

Complex I (NADH:ubiquinone oxidoreductase) is the largest enzyme of the mitochondrial respiratory chain. Compared to its bacterial counterpart which encompasses 14-17 subunits, mitochondrial complex I has almost tripled its subunit composition during evolution of eukaryotes, by recruitment of so-called accessory subunits, part of them being specific to distinct evolutionary lineages. The increasing availability of numerous broadly sampled eukaryotic genomes now enables the reconstruction of the evolutionary history of this large protein complex. Here, a combination of profile-based sequence comparisons and basic structural properties analyses at the protein level enabled to pinpoint homology relationships between complex I subunits from fungi, mammals or green plants, previously identified...

2011-01-01

316

Methanogen community structure in the rumens of farmed sheep, cattle and red deer fed different diets  

British Library Electronic Table of Contents (United Kingdom)

Abstract Development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on knowledge of the methanogens present. We investigated the composition of archaeal communities in the rumens of farmed sheep (Ovis aries), cattle (Bos taurus) and red deer (Cervus elaphus) using denaturing gradient gel electrophoresis (DGGE) to generate fingerprints of archaeal 16S rRNA genes. The total archaeal communities were relatively constant across species and diets, and were less variable and less diverse than bacterial communities. There were diet- and ruminant-species-based differences in archaeal community structure, but the same dominant archaea were present in all rumens. These were members of three coherent clades: species related to Methanobrevibacter ruminan...

2011-01-01

317

In vitro diffusion bed, 3-day repeat challenge `capacity' test for antimicrobial wound dressings:  

British Library Electronic Table of Contents (United Kingdom)

Greenman J, Thorn RMS, Saad S, Austin AJ. In vitro diffusion bed, 3-day repeat challenge `capacity' test for antimicrobial wound dressings. Int Wound J 2006;3:322-329. Abstract The aim of this study was to develop an in vitro wound infection model that allows the comparison of the bacterial kill rate of antimicrobial wound dressings over the course of 3 days, with renewed microbial challenges each day, under realistic wound-like conditions. A test bed model of a moderately exuding wound was constructed from a hydrogel containing releasable foetal calf serum (FCS), and cellulose discs dosed with test microbes (Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa) suspended in 50% FCS applied at the interface between the test dressing and the hydrogel test bed. Freshly prep...

2006-01-01

318

How microcystin-degrading bacteria express microcystin degradation activity  

British Library Electronic Table of Contents (United Kingdom)

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...

2011-01-01

319

Growth promotion and induction of resistance in tomato plant against Xanthomonas euvesicatoria and Alternaria solani by Trichoderma spp.  

British Library Electronic Table of Contents (United Kingdom)

In tomato crop, the induction of resistance emerges as an important alternative for achieving the reduction of chemicals in disease control. This study aimed to evaluate the ability of 28 Trichoderma isolates to promote the growth of tomato seedlings and to induce systemic resistance (ISR) against Xanthomonas euvesicatoria and Alternaria solani, the causal agents of bacterial spot and early blight, respectively. Twelve isolates promoted the increase of plant dry matter mass (DMM) above 100%, showing the great potential of these strains. All isolates were able to colonize the root system of tomato plants. The plant growth-promoting isolates were further evaluated for potential elicitation of ISR. Treatment of the soil with all Trichoderma isolates provided protection in tomato plants from 2...

2011-01-01

320

Functional adaptation of microbial communities from jet fuel-contaminated soil under bioremediation treatment: simulation of pollutant rebound  

British Library Electronic Table of Contents (United Kingdom)

Abstract To investigate the link between the functionality and the diversity of microbial communities under strong selective pressure from pollutants, two types of mesocosms that simulate natural attenuation and phytoremediation were generated using soil from a site highly contaminated with jet fuel and under air-sparging treatment. An increase in the petroleum hydrocarbon concentration from 4900 to 18-500-mg-kg-1-dw soil simulated a pollutant rebound (postremediation pollutant reversal due to residual contamination). Analysis of soil bacterial communities by denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed stronger changes and selection for a phylogenetically diverse microbial population in the mesocosms with pollutant-tolerant willow trees. Enumerat...

2011-01-01

321

Familial unilateral deafness and delayed endolymphatic hydrops  

British Library Electronic Table of Contents (United Kingdom)

Delayed endolymphatic hydrops (DEH) is a unique disorder characterized by fluctuating otologic symptoms in the setting of preexisting unilateral deafness. The symptoms include aural fullness, fluctuating hearing, and/or episodes of vertigo similar to those observed in Meniere disease and may occur ipsilateral or contralateral to the previously deafened ear. In most reported cases, the unilateral deafness has been a profound sensorineural hearing loss with a sudden onset that has been variously attributed to bacterial or viral labyrinthitis, acoustic or cranial trauma, otosclerosis, and congenital CMV infection. Familial occurrence of the syndrome has not previously been reported in the literature. In this report, we describe two possible familial instances of delayed DEH. These patients ra...

2007-01-01

322

Enhanced antibacterial activity of bifunctional Fe3O4-Ag core-shell nanostructures  

British Library Electronic Table of Contents (United Kingdom)

We describe a simple one-pot thermal decomposition method for the production of a stable colloidal suspension of narrowly dispersed superparamagnetic Fe3O4-Ag core-shell nanostructures. These biocompatible nanostructures are highly toxic to microorganisms. Antimicrobial activity studies were carried out on both Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus megaterium and Staphylococcus aureus) bacterial strains. Efforts have been made to understand the underlying molecular mechanism of such antibacterial actions. The effect of the core-shell nanostructures on Gram negative strains was found to be better than that observed for silver nanoparticles. The minimum inhibitory concentration (MIC) values of these nanostructures were found to be considerably lowe...

2009-01-01

323

Electrochromic effects of charge separation in bacterial photosynthesis: theoretical models  

Energy Technology Data Exchange (ETDEWEB)

The primary charge separation in photosynthetic bacteria generates a dimeric bacteriochlorophyll (BChl) cation and a bacteriopheophytin (BPheo) anion which lie within close proximity of each other (approx. 10 A). The two radicals also lie within van der Waals contact on opposite sides of a lone BChl bridging molecule. Spectral changes in the red (Q/sub y/) band of the bridge BChls have been observed on picosecond time scales following excitation of the reaction center (RC) and have been variously attributed to the formation of a BChl anion, to a charge-transfer state, or to electrochromic effects. They present calculations here which suggest that electrochromic effects caused by the photogenerated cation and/or anion can rationalize the optical changes observed in the flash photolyses as well as in trapping experiments.

1987-07-22

324

Electrochemistry of a semiconductor chalcopyrite concentrate leaching by Thiobacillus ferrooxidans  

Energy Technology Data Exchange (ETDEWEB)

Using carbon-paste-CuFeS{sub 2} electrodes and a cyclic voltammetric technique, it was found that a large number of intermediate electrochemical oxidation reactions were associated with the dissolution of chalcopyrite in presence and absence of bacteria. The effects of concentrations of copper, ferrous and ferric ions, as well as of agitation on the peaks of cyclic voltammograms were measured. It was established that chalcopyrite oxidation was solid-state controlled as suggested by the data of chronopotentiometric and chronoamperometric measurements. The activation energy of solid state diffusion of chalcopyrite leaching was determined by the Sand's method to be {triangle}E{sub a} = 20.5 kJ. The leaching mechanism is discussed in terms of solid-state properties (energy bonding) of the n-type semiconductor chalcopyrite and energy density states of redox systems of acidic bacterial leach media. A generalized model for the mechanism of chalcopyrite leaching ...

1991-01-01

325

Effects of Scutellaria baicalensis on chronic cerebral hypoperfusion-induced memory impairments and chronic lipopolysaccharide infusion-induced memory impairments  

British Library Electronic Table of Contents (United Kingdom)

Ethnopharmacological relevance: Extracts of the roots of Scutellaria baicalensis Georgi (Labiatae) have been widely used to relieve fever related to bacterial infection and inflammatory diseases in traditional Korean medicine and have been reported to be effective in brain diseases. These experiments were conducted to examine the effects of oral administration of Scutellaria baicalensis extracts on the rescue of memory impairments induced by chronic cerebral hypoperfusion or chronic lipopolysaccharide (LPS) infusion. In addition, the underlying mechanisms of these effects were investigated. Materials and methods: In the first experiment, chronic cerebral hypoperfusion was induced in male Wister rats by bilateral common carotid artery occlusion (BCCAo). Daily administration of Scutellaria b...

2011-01-01

326

Effect of carbon dioxide on the performance of biogas/diesel dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

Methane and carbon dioxide are the two main constituents of biogas. Biogas also contains traces of nitrogen, hydrogen, oxygen and hydrogen sulphide. When diesel engine runs on biogas, the combustion is poor as compared to diesel fuel. One of the reasons of poor combustion is the presence of carbon dioxide in the biogas. Percentage of methane and carbon dioxide in biogas varies with maturities of feed stock, temperature, water content, loading rate of raw material and bacterial actions. This paper examines the effect of variations of carbon dioxide in biogas on the performance of the engine to simulate the performance of the engine running with biogas from different sources (varying proportion of methane and carbon dioxide). (Author)

1996-09-01

327

Eating the enemy in Crohn's disease  

British Library Electronic Table of Contents (United Kingdom)

Several old and new observations suggest the existence in Crohn's disease of a phagocytic disorder of macrophages related to impaired bactericidal activity of host cells or to the presence of invasive bacteria that have developed strategies to counteract macrophage killing. It was recently reported that disordered macrophage cytokine secretion underlies impaired acute inflammation and bacterial clearance in Crohn's disease. Secretion of proinflammatory cytokines by CD macrophages was impaired in response to E. coli or specific Toll-like receptor agonists. In addition, major advances in the etiology of Crohn's disease came from the existence of polymorphism in NOD2 and autophagy-related susceptibility genes (ATG16L1 and IRGM) in patients and from the identification of the presence of adhere...

2010-01-01

328

Distinctive Responses of Metabolically Active Microbiota to Acidification in a Thermophilic Anaerobic Digester  

British Library Electronic Table of Contents (United Kingdom)

Acidification is one of the most common and serious problems inducing process failure in anaerobic digesters. The production of volatile fatty acids (VFAs) mainly triggers acidic shock. However, little is known about the bacteria involved in the processes of acidogenic metabolism, such as fermentation and reductive acetogenesis. Here, the metabolic responses of a methanogenic community to the acidification and resulting process deterioration were investigated using transcriptional profiling of both the 16S rRNA and formyltetrahydrofolate synthetase (FTHFS) genes. The 16S rRNA-based analyses demonstrated that the dynamic shift of bacterial populations was closely correlated with reactor performance, especially with VFA accumulation levels. The pH drop accompanied by an increase in VFAs stim...

2011-01-01

329

Complexation of nitrogen and sulphur donor Schiff's base ligand to Cr(III) and Ni(II) metal ions: Synthesis, spectroscopic and antipathogenic studies  

British Library Electronic Table of Contents (United Kingdom)

2,6-Diacetyl pyridine based ligand was synthesized by the reaction of 2,6-diacetyl pyridine with thiocarbohydrazide in presence of acetic acid. The coordination compounds with Cr(III) and Ni(II) metal ions having [Cr(L)X]X2 and [Ni(L)X]X compositions (where L=ligand and X=NO3^-, Cl^- and CH3COO^-) were synthesized and characterized by physicochemical and spectral studies. The studies like elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, UV-Vis, NMR, mass and EPR reveal that the complexes are octahedral. The compounds were examined against the pathogenic fungal and bacterial strains like Alternaria brassicae, Aspergillus niger, Fusarium oxysporum, Xanthomonas compestris and Pseudomonas aeruginosa. A. niger causes the diseases Apergillosis and Oto...

2011-01-01

330

Chitinolytic enzyme production and genetic improvement of a new isolate belonging to Streptomyces anulatus  

British Library Electronic Table of Contents (United Kingdom)

Thirty bacterial isolates were obtained from different sources and sites at Jeddah, Saudi Arabia, on chitin agar medium; 9 of the 30 isolates were cultured in liquid medium containing chitin as sole carbon and nitrogen sources. Isolate SM21, which was isolated from shrimp shells, showed the best growth and chitinase production in liquid medium. According to its morphological, physiological and biochemical characteristics, SM21 belongs to the genus Streptomyces and was identified as Streptomyces anulatus SM21. Identification was confirmed using 16S rDNA analysis. The chitinase enzyme was precipitated with 80% NH4SO4 and purified using DEAE-cellulose ion exchange chromatography followed by Sephadex G-100 gel filtration. The molecular weight determined using sodium dodecyl sulfate polyacrylam...

2011-01-01

331

Chemical and microbial properties of mahyaveh, a traditional Iranian fish sauce  

British Library Electronic Table of Contents (United Kingdom)

To the best of our knowledge, this is the first report on the chemical and microbial properties of traditional Iranian fish sauce, mahyaveh. Fish sauce samples used in this study originated from five different locations in the Southern part of Iran. The pH of mahyaveh samples from different locations was in the range of 4.89-7.55 and NaCl concentration was in the range of 7.48-17.1%. The overall mean of TVB-N in all the samples tested was 3098 mg/kg. Histamine, with the overall mean of 2662 mg/kg, was found to be the main biogenic amine in the Iranian fish sauce. The high histamine content can be related to the high levels of bacterial count especially enterobacteriaceae (overall mean of 3.41 log cfu/g) and lactic acid bacteria (overall mean of 4.13 log cfu/g) in this product. Spermidine w...

2012-01-01

332

Bottom-up carbon subsidies and top-down predation pressure interact to affect aquatic food web structure  

British Library Electronic Table of Contents (United Kingdom)

Human impacts such as eutrophication, overexploitation and climate change currently threaten future global food and drinking water supplies. Consequently, it is important that we understand how anthropogenic resource (bottom-up) and consumer (top-down) manipulations affect aquatic food web structure and production. Future climate changes are predicted to increase the inputs of terrestrial dissolved organic carbon to lakes. These carbon subsidies can either increase or decrease total basal production in aquatic food webs, depending on bacterial competition with phytoplankton for nutrients. This study examines the effects of carbon subsidies (bottom-up) on a pelagic community exposed to different levels of top-down predation. We conducted a large scale mesocosm experiment in an oligotrophic ...

2011-01-01

333

Assessing the effect of an antimicrobial wound dressing on biofilms  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT To date the effect of silver-containing wound dressings on biofilms, known to be present in chronic wounds, has not been determined or documented. In this current study, we aimed to determine the antimicrobial effect of a silver-containing dressing on biofilms grown in a chambered slide model. Before the addition of a wound dressing onto a 24-hour biofilm, composed of either Pseudomonas aeruginosa, Enterobacter cloacae, Staphylococcus aureus, or a mixed bacterial community, a fluorescent dye was applied. This enabled the viability of sessile bacteria to be monitored in real-time, using a rapid form of confocal laser scanning microscopy over a contact time period of 48 hours. By analyzing all the three-dimensional data generated from the confocal time-lapse sequences, 90% of all se...

2008-01-01

334

Application of a leukocyte and nitrite urine test strip to the management of children with neurogenic bladder.  

Science.gov (United States)

A urine leukocyte count of > or = 50/mm3 together with a bacterial count of > or = 10(5) colony-forming units (CFUs) per milliliter was used to define significant infection in 160 children with neurogenic bladder and evaluate the leukocyte and nitrite components of the Chemstrip 9 test. A Chemstrip 9 leukocyte reading of or = 500 leukocytes together with a positive nitrite reaction occurred in 18 children and had a sensitivity of 40% with a 100% positive predictive value for infection. Other combinations of Chemstrip 9 leukocyte and nitrite reactions were unhelpful or of uncertain value. Selection of up to three specimens from each patient increased the number of samples to 360 and provided general confirmation of the above conclusions. Nitrofurantoin may reduce the sensitivity of the nitrite strip reaction. PMID:8359003

1993-07-01

335

Antimicrobial Edible Apple Films Inactivate Antibiotic Resistant and Susceptible-Campylobacter jejuni-Strains on Chicken Breast  

British Library Electronic Table of Contents (United Kingdom)

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 ...

2011-01-01

336

Anti-Infection Dip Suggestions for the Coloplast Titan Inflatable Penile Prosthesis in the Era of the Infection Retardant Coated Implant  

British Library Electronic Table of Contents (United Kingdom)

Abstract Introduction.- Infection is the worst complication seen with inflatable penile prosthesis (IPP). Both the American Medical Systems (AMS) and Coloplast IPP have infection retardant coatings. AMS is coated at the factory with rifampicin and minocycline (InhibiZone). The Coloplast IPP has a hydrophilic coating covalently bonded to its components that will absorb any aqueous solution before implantation and provides increased surface lubricity to decrease bacterial adherence. Aim.- We tested several antibiotic dips comparing zones of inhibition (ZOI) against five commonly infecting bacteria with coated Coloplast implants. Results were compared with those ZOI created with strips of an AMS IPP precoated with InhibiZone. Methods.- Pieces of sterile Coloplast Titan IPP were dipped in (i) ...

2011-01-01

337

An overview of field-specific designs of microbial EOR  

Energy Technology Data Exchange (ETDEWEB)

The selection and design of an MEOR process for application in a specific field involves geological, reservoir, and biological characterization. Microbially mediated oil recovery mechanisms (bigenic gas, biopolymers, and biosurfactants) are defined by the types of microorganisms used. The engineering and biological character of a given reservoir must be understood to correctly select a microbial system to enhance oil recovery. This paper discusses the methods used to evaluate three fields with distinct characteristics and production problems for the applicability of MEOR would not be applicable in two of the three fields considered. The development of a microbial oil recovery process for the third field appeared promising. Development of a bacterial consortium capable of producing the desired metabolites was initiated, and field isolates were characterized.

1995-12-31

338

Amphiphilic Polyanhydride Films Promote Neural Stem Cell Adhesion and Differentiation  

British Library Electronic Table of Contents (United Kingdom)

Several challenges currently exist for rational design of functional tissue engineering constructs within the host, which include appropriate cellular integration, avoidance of bacterial infections, and low inflammatory stimulation. This work describes a novel class of biodegradable, amphiphilic polyanhydrides with many desirable protein-material and cell-material attributes capable of confronting these challenges. The biocompatible amphiphilic polymer films were shown to release laminin in a stable and controlled manner, promote neural cell adhesion and differentiation, and evade inflammatory responses of the immune system. Using high-throughput approaches, it was shown that polymer chemistry plays an integral role in controlling cell?film interactions, which suggests that these polyanhyd...

2011-01-01

339

3D model for a secondary facultative pond  

British Library Electronic Table of Contents (United Kingdom)

This paper describes a comprehensive model of wastewater treatment in secondary facultative ponds, which combines 3D hydrodynamics with a mechanistic water quality model. The hydrodynamics are based on the Navier-Stokes equation for incompressible fluids under shallow water and Boussinesq assumptions capturing the flow dynamics along length, breadth and depth of the pond. The water quality sub model is based on the Activated Sludge Model (ASM) concept, describing COD and nutrient removal as function of bacterial growth following Monod kinetics, except for Escherichia coli removal, which was modelled as first order decay. The model was implemented in the Delft3D software and was used to evaluate the effect of wind and the addition of baffles on the water flow pattern, temperature profiles i...

2011-01-01

340

Sudden infant death syndrome and placental disorders: the thyroid-selenium link.  

Science.gov (United States)

Placental insufficiency, inducing hypoxia-ischaemia, is considered a major cause of neuronal injury and impaired post natal development. Placental insufficiency alters the metabolism of arachidonic acid and its oxidation products. Premature labour and low-birth-weight infants are associated with reduced intrauterine blood-flow and infections of the reproductive tract. Thyroidal activity is depressed in undernutrition (placental insufficiency). Premature infants require extra vitamin C for normal tyrosine metabolism (tyrosine is the thyroxine precursor). Among the symptoms indicating infantile cretinism, which appear during 3-5 months of age are: delayed union of skull bones, torpid behaviour, slow feeding, cyanosis during feeding, excessive sleepiness, enlarged tongue, umbilical herniation, flabby musculature, short stature and delayed development. These symptoms have all been described in low-birth-weight infants and sudden infant death syndrome victims by various authors. Bacteria ...

1997-04-01

341

Safety evaluation of Propionibacterium freudenreichii ET-3 culture.  

Science.gov (United States)

Propionibacterium freudenreichii ET-3 culture, a cell-free product of whey fermentation using P. freudenreichii ET-3 (7025), has been shown to promote the growth of Bifidobacteria through the action of 1,4-dihydroxy-2-naphthoic acid (DHNA), and therefore, has potential use in the food and supplement industries. Although currently used as a food ingredient in Japan, the safety of this novel ingredient has not been previously evaluated through traditional toxicity testing. Therefore, here we report the results of standard toxicological testing performed on P. freudenreichii ET-3 culture. In a 4-week oral toxicity study, administration of 6000mg/kg body weight/day P. freudenreichii ET-3 culture was without compound-related adverse effects on clinical signs, body weights, food consumption, ophthalmology, hematology, clinical chemistry, urinalysis, organ weights, and gross and microscopic findings in male and female Sprague-Dawley rats. Furthermore, in vitro mutagenicity testing ...

2011-03-22

342

Microbial dynamics in upflow anaerobic sludge blanket (UASB) bioreactor granules in response to short-term changes in substrate feed  

Science.gov (United States)

The complexity and diversity of the microbial communities in biogranules from an upflow anaerobic sludge blanket (UASB) bioreactor were determined in response to short-term changes in substrate feeds. The reactor was fed simulated brewery wastewater (SBWW) (70% ethanol, 15% acetate, 15% propionate) for 1.5 months (phase 1), acetate / sulfate for 2 months (phase 2), acetate-alone for 3 months (phase 3), and then a return to SBWW for 2 months (phase 4). Performance of the reactor remained relatively stable throughout the experiment as shown by COD removal and gas production. 16S rDNA, methanogen-associated mcrA and sulfate reducer-associated dsrAB genes were PCR amplified, then cloned and sequenced. Sequence analysis of 16S clone libraries showed a relatively simple community composed mainly of the methanogenic Archaea (Methanobacterium and Methanosaeta), members of the Green Non-Sulfur (Chloroflexi) group of Bacteria, followed by fewer numbers of Syntrophobacter, Spirochaeta, ...

2010-08-01

343

Anaerobic thermophilic bacteria isolated from a Venezuelan oil field and its potential use in microbial improved oil recovery  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to determine the ability of indigenous bacteria from a Venezuelan oil field to grow under reservoir conditions inside a porous media, and to produce metabolites capable of recovering residual crude oil. For this purpose, samples of formation waters from a central-eastern Venezuelan oil reservoir were enriched with different carbon sources and a mineral basal media. Formation water was used as a source of trace metals. The enrichments obtained were incubated at reservoir temperature (71{degrees}C), reservoir pressure (1,200 psi), and under anaerobic conditions for both outside and inside porous media (Berea core). Growth and metabolic activity was followed outside porous media by measuring absorbance at 660 nm, increases in pressure, and decreases in pH. Inside porous media bacterial activity was determined by visual examination of the produced waters (gas bubbles and bacterial cells). All the carbohydrates tested ...

1995-12-31

344

Widely Linear Kalman Filtering  

CERN Document Server

For a zero mean, proper, complex random vector x, the Hermitian covariance ExxH is a complete second-order characterization. However, if the vector x is improper, it is correlated with its complex conjugate, meaning ExxT = 0. This improper or complementary covariance must be accounted for in a complete second-order characterization. The improper covariance has been exploited for widely linear (WL) Wiener filters and WL minimum mean squared error (MMSE) estimators, and the improvement in performance of the WLMMSE estimator over the LMMSE estimator has been quantified. In this paper we consider the design of the widely linear Kalman filter (WLKF). We analyze the WLKF, extended WLKF, and unscented WLKF. The key idea of this paper is to modify the error covariance matrices and the construction of effective sigma points in the WLKF in a systematic way that exploits the Hermitian and complementary covariance of improper states and noises.

2011-01-01

345

Vibration testing of the I-40 bridge before and after the introduction of damage  

Energy Technology Data Exchange (ETDEWEB)

Because the bridges over the Rio Grande were to be razed, the investigators were able to introduce simulated cracks in four stages of increasing length into the structure. This paper summarizes the results of ambient and conventional, measured-input, modal analyses, performed on the undamaged structure. Also summarized are the results of conventional modal analyses performed after each stage of damage had been introduced. These tests were intended to quantify the amount of damage necessary to produce changes in the global dynamic properties of the bridge and to form a data base that can be used by other investigators to develop damage identification algorithms. Conventional modal analysis identified changes in the global dynamic properties of the structure only after the final stage of a damage.

1994-11-01

346

Transmission nuclear resonance fluorescence measurements of "2"3"8U in thick targets  

International Nuclear Information System (INIS)

Transmission nuclear resonance fluorescence measurements were made on targets consisting of Pb and depleted U with total areal densities near 86g/cm"2. The "2"3"8U content in the targets varied from 0% to 8.5% (atom fraction). The experiment demonstrates the capability of using transmission measurements as a non-destructive technique to identify and quantify the presence of an isotope in samples with thicknesses comparable to the average thickness of a nuclear fuel assembly. The experimental data also appear to demonstrate the process of notch refilling with a predictable intensity. Comparison of measured spectra to previous backscatter "2"3"8U measurements indicates general agreement in observed excited states. Evidence of two new "2"3"8U excited states and possibly a third state have also been observed.

2011-05-15

347

Tissue Heterogeneity in IMRT Dose Calculation for Lung Cancer  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to evaluate the differences in accuracy of dose calculation between 3 commonly used algorithms, the Pencil Beam algorithm (PB), the Anisotropic Analytical Algorithm (AAA), and the Collapsed Cone Convolution Superposition (CCCS) for intensity-modulated radiation therapy (IMRT). The 2D dose distributions obtained with the 3 algorithms were compared on each CT slice pixel by pixel, using the MATLAB code (The MathWorks, Natick, MA) and the agreement was assessed with the gamma function. The effect of the differences on dose-volume histograms (DVHs), tumor control, and normal tissue complication probability (TCP and NTCP) were also evaluated, and its significance was quantified by using a nonparametric test. In general PB generates regions of over-dosage both in the l...

2011-01-01

348

Thermal radiation from hot surfaces measured by optical and calorimetric methods. Master's thesis  

Energy Technology Data Exchange (ETDEWEB)

The radiative heat loss from a surface is determined by its total hemispherical emittance, which consequently plays an important role in aerospace and solar applications. This study compares emittances measured calorimetrically with values derived from near normal incidence spectral reflectance measurements. This optical derivation is based on a number of assumptions which limit the accuracy if not sufficiency fulfilled. These assumptions include sample specularity, a straybody character beyond the range of measurement, only small variations of emittance with temperature, and a perfectly smooth sample surface. The comparison of calorimetrically and optically derived emittance performed in this study not only quantifies the errors introduced by insufficient fulfillment of the assumptions but also identifies which assumption causes the dominant error. The calorimetric emissometer, constructed for this study and based on a heat flow sensor, was calibrated with ...

1982-01-01

349

The influence of Cu contamination on Nereis diversicolor bioturbation  

British Library Electronic Table of Contents (United Kingdom)

Aquatic sediments feature a two-way interaction between contaminants and benthic macrofauna. The effect of the macrofauna community on the transport of contaminants in sediment has received considerable attention. Yet, few studies have investigated the reverse effect, i.e., the influence of contaminants on bioturbation activity. To this end, we performed laboratory experiments to investigate the effect of copper contamination on sediment reworking activity of the ragworm Nereis diversicolor. A density of 570 ind m2 was introduced in mesocosms containing natural and copper spiked (2.99 nmol Cu g?1) cohesive intertidal sediments from Ponta da Erva (Tejo estuary, Portugal). Luminophore tracers were used to quantify sediment reworking activity over time (2, 7, 14 and 21 days). Bioturbation was...

2006-01-01

350

The external water footprint of the Netherlands: Geographically-explicit quantification and impact assessment  

British Library Electronic Table of Contents (United Kingdom)

This study quantifies the external water footprint of the Netherlands by partner country and import product and assesses the impact of this footprint by contrasting the geographically-explicit water footprint with water scarcity in the different parts of the world. The total water footprint of the Netherlands is estimated to be about 2300 m^3/year/cap, of which 67% relates to the consumption of agricultural goods, 31% to the consumption of industrial goods, and 2% to domestic water use. The Dutch water footprint related to the consumption of agricultural goods, is composed as follows: 46% related to livestock products; 17% oil crops and oil from oil crops; 12% coffee, tea, cocoa and tobacco; 8% cereals and beer; 6% cotton products; 5% fruits; and 6% other agricultural products. About 11% o...

2009-01-01

351

The estimation of lifetime distribution of Alloy 800 steam generator tubing  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of degradation on reliability of SG tubing.

2009-10-15

352

The estimation of lifetime distribution of Alloy 800 steam generator tubing  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of degradation on reliability of SG tubing.

2009-10-01

353

The Dissipative Merger Progenitors of Elliptical Galaxies  

CERN Document Server

We address the deviations of the scaling relations of elliptical galaxies from the expectations based on the virial theorem and homology, including the "tilt" of the "fundamental plane" and the steep decline of density with mass. We show that such tilts result from dissipative major mergers once the gas fraction available for dissipation declines with progenitor mass, and derive the scaling properties of the progenitors. We use hydrodynamical simulations to quantify the effects of major mergers with different gas fractions on the structural properties of galaxies. The tilts are driven by the differential shrinkage of the effective stellar radius as a function of dissipation in the merger, while the correlated smaller enhancements in internal velocity and stellar mass keep the slope of the velocity-stellar mass relation near V \\pr M_*^{1/4}. The progenitors match a straightforward model of disc formation in LCDM haloes. Their total to stellar mass ratio within the ...

2006-01-01

354

The Concentration-Density Relation of Galaxies in Las Campanas Redshift Survey  

CERN Document Server

We report the results of the evaluation of the ``concentration-density'' relation of galaxies in the local universe, taking advantage of the very large and homogeneous data set available from the Las Campanas Redshift Survey (Shectman et al. 1996). This data set consists of galaxies inhabiting the entire range of galactic environments, from the sparsest field to the densest clusters, thus allowing us to study environmental variations without combining multiple data sets with inhomogeneous characteristics. Concentration is quantified by the automatically-measured concentration index $C$, which is a good measure of a galaxy's bulge-to-disk ratio. The environment of the sample galaxies is characterized both by the three-space local galaxy density and by membership in groups and clusters. We find that the distribution of C in galaxy populations varies both with local density and with cluster/group membership: the fraction of centrally-concentrated galaxies increases ...

1999-01-01

355

The Bedwyr system for model checking over syntactic expressions  

CERN Document Server

Bedwyr is a generalization of logic programming that allows model checking directly on syntactic expressions possibly containing bindings. This system, written in OCaml, is a direct implementation of two recent advances in the theory of proof search. The first is centered on the fact that both finite success and finite failure can be captured in the sequent calculus by incorporating inference rules for {\\em definitions} that allow {\\em fixed points} to be explored. As a result, proof search in such a sequent calculus can capture simple model checking problems as well as may and must behavior in operational semantics. The second is that higher-order abstract syntax is directly supported using term-level $\\lambda$-binders and the quantifier known as $\

2007-01-01

356

Taxa-specific heat shock proteins are over-expressed with crowding in the Australian plague locust  

British Library Electronic Table of Contents (United Kingdom)

Most heat shock proteins (Hsps) function as molecular chaperones that help organisms to cope with stress. Although the best empirical evidence is related to heat shock, there is evidence that Hsps and their encoding genes are involved in resistance to other ecologically relevant types of stresses such as those imposed by high population density. We quantified density-dependent gene expression of large (i.e. Hsp40, Hsc70 and Hsp90) and small (Hsp20.5, Hsp20.6 and Hsp20.7) heat shock genes in neural tissue of fifth-instar nymphs of the Australian plague locust, Chortoicetes terminifera, using reverse transcription-quantitative PCR. Locusts are of particular interest when studying the influence of stress induced by high population density since they show an extreme form of phenotypic plastici...

2011-01-01

357

Surfactant studies for bench-scale operation. Quarterly technical progress report No. 2, 1 October-31 December 1992  

Science.gov (United States)

A phase 2 study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This report covers the second quarter of work. The major accomplishments were: completion of coal liquefaction autoclave reactor runs with Illinois number 6 coal at processing temperatures of 300, 325, and 350 C, and pressures of 1800 psig; analysis of the filter cake and the filtrate obtained from the treated slurry in each run; and correlation of the coal conversions and the liquid yield quality to the surfactant concentration. An increase in coal conversions and upgrading of the liquid product quality due to surfactant addition was observed for all runs.

1993-03-01

358

Surfactant studies for bench-scale operation. Quarterly technical progress report No. 1, 1 July-30 September 1992  

Energy Technology Data Exchange (ETDEWEB)

A phase 2 study was initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This publication covers the first quarter of work. The major accomplishments were: the refurbishment of the high-pressure, high-temperature reactor autoclave, the completion of four coal liquefaction runs with Pittsburgh No. 8 coal, two each with and without sodium lignosulfonate surfactant, and the development of an analysis scheme for the product liquid filtrate and filter cake. Initial results at low reactor temperatures show that the addition of the surfactant produces an improvement in conversion yields and an increase in lighter boiling point fractions for the filtrate.

1992-12-01

359

Structural health monitoring of constrained tapered beamlike structures using natural frequencies and nodal points  

Science.gov (United States)

The integrity and safety of beam-like structures are dependent in part on their boundary conditions which can vary with time due to damage or aging. Structural health monitoring of such structures should therefore include attention to boundary conditions. Where the boundary conditions can be represented by a lumped spring then the identification of associated stiffness parameter values may be a means to quantifying the integrity of the support. This paper investigates such a method for identifying the equivalent translational and rotational stiffness of a constrained tapered beam-like structure. An analytical model of a beam of tapered width and thickness is adopted as a simplified representation of a tower-like structure. The model is used to explore in what scenarios natural frequencies and/or nodal points might be sufficiently sensitive to changes in support conditions to be measurable indicators of damage. The method is evaluated by Monte Carlo simulations for ...

2011-07-01

360

Status of the surry low power and shutdown PRA  

International Nuclear Information System (INIS)

The Surry low power and shutdown probabilistic risk analysis (PRA) is an ongoing project at Brookhaven National Laboratory (BNL) to identify and quantify potential accident scenarios that may occur in a pressurized water reactor (PWR) during low power and shutdown. It was initiated as a result of various incidents and accidents that have occurred within the United States and overseas. The project involves review and evaluation of PWR experience at shutdown, identification of accident scenarios, determination of methods to mitigate the accidents, and performance a level 1 PRA. An evaluation of accident progression, source terms and consequences has also been initiated. The results will be used to address issues related to shutdown conditions. The objective of this paper is to provide a progress report on the project, and to present the approach used as well as the preliminary results of the ongoing and completed tasks.

1991-04-01

361

Stability of Combat Exposure Recall in Operation Iraqi Freedom Veterans  

British Library Electronic Table of Contents (United Kingdom)

PurposeThis study evaluates changes in recall of combat exposures over the first year after return from deployment. The research purpose is to assess whether recall of combat exposures is consistent at different time points; if not, what demographic and/or PTSD symptom risk factors exist for any directional instability. MethodsSurveys completed by soldiers at 3, 6, and 12 months post-Operation Iraqi Freedom (OIF) deployment were linked for longitudinal analysis in a previous study in which three matched datasets were created: 3-6 months (N = 768), 6-12 months (N = 341), and 3-12 months (N = 445). Post-traumatic stress disorder (PTSD) was assessed by using the National Center for PTSD Checklist. The reliability of recall for 36 combat exposures was quantified. The effects of demographics an...

2010-01-01

362

Scenarios of internal fuel demand: Otto cycle engines and CO{sub 2} reduction due to the alcohol production and consumption in Brazil; Cenarios de demanda interna de combustiveis: motores ciclo Otto e abatimento de CO{sub 2} devido a producao e ao uso de alcool no Brasil  

Energy Technology Data Exchange (ETDEWEB)

This paper quantifies the avoided CO{sub 2} emission due to the using, as vehicle fuel, of the alcohol produced in Brazil during the period 1995 - 2025. With this purpose, internal demand sceneries were elaborated for Otto cycle engines. The results suggest that the introduction of the flex-fuel and the increasing of the production and using of hydrated alcohol can reduce up to 1.23 Gt of CO{sub 2} equivalent during the period 2003 - 2025, representing an annual average of 53.5 Mt CO{sub 2} equivalent.

2006-07-01

363

Responses of terrestrial ecosystems to temperature and precipitation change: a meta analysis of experimental manipulation  

British Library Electronic Table of Contents (United Kingdom)

Abstract Global mean temperature is predicted to increase by 2 7 C and precipitation to change across the globe by the end of this century. To quantify climate effects on ecosystem processes, a number of climate change experiments have been established around the world in various ecosystems. Despite these efforts, general responses of terrestrial ecosystems to changes in temperature and precipitation, and especially to their combined effects, remain unclear. We used meta analysis to synthesize ecosystem level responses to warming, altered precipitation, and their combination. We focused on plant growth and ecosystem carbon (C) balance, including biomass, net primary production (NPP), respiration, net ecosystem exchange (NEE), and ecosystem photosynthesis, synthesizing results from 85 studi...

2011-01-01

364

Resistance pattern and antioxidant enzyme profiles of protoporphyrinogen oxidase (PROTOX) inhibitor-resistant transgenic rice  

British Library Electronic Table of Contents (United Kingdom)

We quantified the resistance levels of transgenic rice plants, expressing Myxococcus xanthus protoporphyrinogen oxidase (PROTOX) in chloroplasts and mitochondria, to PROTOX inhibitors, acifluorfen, oxyfluorfen, carfentrazone-ethyl, and oxadiazon. We also determined whether active oxygen species-scavenging enzymes are involved in the resistance mechanism of transgenic rice. The transgenic rice line M4 was about >200-fold more resistant to oxyfluorfen than the wild-type (WT). M4 was also resistant to acifluorfen, carfentrazone-ethyl, and oxadiazon, but did not show multiple resistance to imazapyr and paraquat, which have different target sites. Acifluorfen, oxyfluorfen, carfentrazone-ethyl, and oxadiazon reduced the chlorophyll content in leaves of WT, but had minimal or no effect on M4. The...

2008-01-01

365

Relationship between tourism demand in the Swiss Alps and hot summer air temperatures associated with climate change  

British Library Electronic Table of Contents (United Kingdom)

We quantified the impacts of hot summer air temperatures on tourism in the Swiss Alps by analysing the relationship between temperature and overnight stays in 40 Alpine resorts. Several temperature thresholds were tested to detect the relationship between them and summer tourism. Our results reveal significant correlations between the number of nights spent in mountain resorts and hot temperatures at lower elevations. The relationship between hot temperatures and overnight stays is more important in June and to a lesser extent in August than in July. This is probably because holidays and the peak of domestic tourist demand in summer usually take place between the beginning of July and mid-August so that long-term planned stays dominate more during these months compared to June. The alpine ...

2011-01-01

366

Regional application of natural-gas-fired combined-cycle power generation  

Energy Technology Data Exchange (ETDEWEB)

The results of a study assessing natural-gas-fired combined-cycle (GFCC) power generation in the electric-utility sector are presented. This study quantified the economic benefits attributable to GFCC generation and examined the characteristics of GFCC technology that produce these benefits and the ways that these benefits vary among regions in the country. The impacts of changes in important economic parameters (capital cost, fuel price, etc.) as well as the impact of advances in GFCC technology were considered. Use of GFCC technology in the electric-utility sector could play an important role in a least-cost planning strategy and thereby provide significant benefits to the utilities and their customers. Potential benefits include reduced capital and operating costs, more effective matching of load growth and capacity additions, and greater system reliability. 8 refs., 3 tabs.

1989-01-01

367

Radiosterilization of drugs in aqueous solutions may be achieved by the use of radioprotective excipients  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to assess the feasibility of radiosterilization of drugs aqueous solutions and to evaluate the effects of some additives, such as mannitol, nicotinamide and pyridoxine, which might protect the drug from degradation. Metoclopramide was selected as a model drug. The structures of the degradation products were determined to gain insight on the radiolysis mechanisms in aqueous solution in order to design strategies to lower the drug degradation.Metoclopramide hydrochloride aqueous solutions with and without excipients were irradiated either with gamma rays or high-energy electrons. HPLC-DAD was used to measure the loss of chemical potency and to quantify the degradation products which were also characterized by LC-APCI-MS-MS. Metoclopramide recovery for gamma and elec...

2008-01-01

368

Quantitative easing works: Lessons from the unique experience in Japan 2001-2006  

British Library Electronic Table of Contents (United Kingdom)

Abstract: The current financial crisis has now led most major central banks to rely on quantitative easing. The unique Japanese experience of quantitative easing is the only experience which enables us to judge this therapy's effectiveness and the timing of the exit strategy. In this paper, we provide a new empirical framework to examine the effectiveness of Japanese monetary policy during the ''lost'' decade and quantify the effect of quantitative easing on Japan's activity and prices. We combine advantages of Markov-switching VAR methodology with those of factor analysis to establish two major findings. First, we show that the decisive change in regime occurred in two steps: it crept out from late 1995 and established itself durably in February 1999. Second, we show for the first time th...

2011-01-01

369

Quantitation of infectious myonecrosis virus in different tissues of naturally infected Pacific white shrimp, Litopenaeus vannamei, using real-time PCR with SYBR Green chemistry  

British Library Electronic Table of Contents (United Kingdom)

The Pacific white shrimp, Litopenaeus vannamei, is the most important shrimp species in volume in world aquaculture. However, in recent decades, outbreaks of diseases, especially viral diseases, have led to significant economic losses, threatening the sustainability of shrimp farming worldwide. In 2004, Brazilian shrimp farming was seriously affected by a new disease caused by the Infectious myonecrosis virus (IMNV). Thus, disease control based on rapid and sensitive pathogen detection methods has become a priority. In this study, a specific quantitation method for IMNV was developed using real-time PCR with SYBR Green chemistry and viral load of the principal target tissues of chronically infected animals was quantified. The quantitative analysis revealed that mean viral load ranged from ...

2011-01-01

370

Quantifying costs of forecast errors: A case study of the warehouse environment  

British Library Electronic Table of Contents (United Kingdom)

Our study evaluates the impact of forecast errors on organizational cost by simulating a labor-intensive warehouse environment using realistic cost data from a case study. Unlike past studies that measure forecast error in terms of forecast standard deviation, our study also considers the impact of forecast bias, and the complex interaction between these variables. Two cases of organizational cost curves are considered, with differing and asymmetric structures. Results find forecast bias to have a considerably greater impact on organizational cost than forecast standard deviation. Particularly damaging is a high bias in the presence of high forecast standard deviation. Although biasing the forecast in the least costly direction is shown to yield lower costs, sensitivity analysis shows that...

2009-01-01

371

Quantifying bank erosion on the South River from 1937 to 2005, and its importance in assessing Hg contamination  

British Library Electronic Table of Contents (United Kingdom)

Bank sediments along a 40km reach of the South River, downstream of Waynesboro, VA, store mercury from historical contamination as a result of textile manufacturing. Knowledge of the rate at which contaminated sediment is released to the stream channel through bank erosion is required to implement restoration programs designed, for example, to minimize its ecological impact and to reduce risk to human health. Digitized stream channel boundaries based on visual interpretations of georeferenced aerial imagery from 1937 and 2005 were compared to calculate a minimum estimate of the total area of bank sediment eroded between Waynesboro and Port Republic, Virginia. Estimates of riverbank height were extracted from aerial LIDAR data, allowing areal estimates of bank retreat to be converted to vol...

2009-01-01

372

Quantification of the influence of the choice of the algorithm and planning system on the calculation of a treatment plan  

International Nuclear Information System (INIS)

In this work an analysis of the influence of the choice of the algorithm or planning system, on the calculus of the same treatment plan is introduced. For this purpose specific software has been developed for comparing plans of a series of IMRT cases of prostate and head and neck cancer calculated using the convolution, superposition and fast superposition algorithms implemented in the XiO 4.40 planning system (CMS). It has also been used for the comparison of the same treatment plan for lung pathology calculated in XiO with the mentioned algorithms, and calculated in the Plan 4.1 planning system (Brainlab) using its pencil beam algorithm. Differences in dose among the treatment plans have been quantified using a set of metrics. The recommendation for the dosimetrist of a careful choice of the algorithm has been numerically confirmed. (Author).

373

Quantification and reduction of the uncertainty in mass balance models by Monte Carlo analysis of prior data  

Energy Technology Data Exchange (ETDEWEB)

The general objective of this workshop is to investigate and discuss methods by which uncertainties in mass balance models for toxics in the Great Lakes may be reduced. As described by the workshop prospectus, this paper is focused on problems of reducing (and quantifying) uncertainty as they relate to in situ field observations/system response measurements for the establishment of initial conditions, boundary conditions, calibration/confirmation data sets, and model post-audit data sets.'' I have taken this description to refer not only to the evaluation of uncertainty in the field observations themselves, but also to the uncertainty associated the analyses of in situ observations as they interact in the overall modeling process. Thus, I will be concerned here with quantification and reduction of uncertainty both (1) as they may be applied to descriptions of the system that is being modeled and (2) as they may be associated with model ...

1991-01-01

374

Potential of AMS for Quantifying Long-Lived Reaction Products  

International Nuclear Information System (INIS)

Accelerator mass spectrometry (AMS) represents a powerful technique for the detection of long-lived radionuclides through ultra-low isotope ratio measurements. In many cases, counting atoms rather than decays yields much higher sensitivities. The potential of AMS will be demonstrated on typical radionuclides of interest with half-lives between some tens of years up to a hundred million years. The precise measurement of the 27Al(n,2n)26Al excitation function will be exemplified. Lack of information exists for a list of nuclides as pointed out by nuclear data requests. A brief overview on detection limits and some applications for selected long-lived radionuclides is given.

2005-05-24

375

Plasma carotenoids and risk of acute myocardial infarction in the Singapore Chinese Health Study  

British Library Electronic Table of Contents (United Kingdom)

Background and aimModification of low-density lipoprotein due to oxidative stress is essential in the development of coronary atherosclerosis. Data of specific carotenoids except b-carotene on cardioprotective effects in humans are limited. Methods and resultsThis study examined the associations between plasma concentrations of specific carotenoids and incidence of acute myocardial infarction. The study included 280 incident cases of acute myocardial infarction and 560 matched controls nested within the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women aged 45-74 years old enrolled in 1993-1998 in Singapore. Retinol and carotenoids in prediagnostic plasma were quantified using high-performance liquid chromatography. High levels of plasma b-cryptoxanthin a...

2011-01-01

376

Phase Information and the Evolution of Cosmological Density Perturbations  

CERN Document Server

The Fourier transform of cosmological density perturbations can be represented in terms of amplitudes and phases for each Fourier mode. We investigate the phase evolution of these modes using a mixture of analytical and numerical techniques. Using a toy model of one-dimensional perturbations evolving under the Zel'dovich approximation as an initial motivation, we develop a statistic that quantifies the information content of the distribution of phases. Using numerical simulations beginning with more realistic Gaussian random-phase initial conditions, we show that the information content of the phases grows from zero in the initial conditions, first slowly and then rapidly when structures become non-linear. This growth of phase information can be expressed in terms of an effective entropy: Gaussian initial conditions are a maximum entropy realisation of the initial power spectrum, gravitational evolution decreases the phase entropy. We show that our definition of ...

2000-01-01

377

Pesticide residue level in tea ecosystems of Hill and Dooars regions of West Bengal, India  

British Library Electronic Table of Contents (United Kingdom)

In the present study we quantified the residues of organophosphorus (e.g. ethion and chlorpyrifos), organochlorine (e.g. heptachlor, dicofol, ?-endosulfan, ?-endosulfan, endosulfan sulfate) and synthetic pyrethroid (e.g. cypermethrin and deltamethrin) pesticides in made tea, fresh tea leaves, soils and water bodies from selected tea gardens in the Dooars and Hill regions of West Bengal, India during April and November, 2006. The organophosphorus (OP) pesticide residues were detected in 100% substrate samples of made tea, fresh tea leaves and soil in the Dooars region. In the Hill region, 20% to 40% of the substrate samples contained residues of organophosphorus (OP) pesticides. The organochlorine (OC) pesticide residues were detected in 33% to 100% of the substrate samples, excluding the w...

2009-01-01

378

PKH26 as a fluorescent label for live human umbilical mesenchymal stem cells  

British Library Electronic Table of Contents (United Kingdom)

To determine whether PKH26 labeling affects the morphologies, phenotypes, proliferation, and secretion abilities of human umbilical mesenchymal stromal cells (HUMSCs) were investigated. Isolated HUMSCs were labeled with PKH26, and cell morphology was observed under microscope. Cell cycle, apoptotic cell death, expression of PKH26, and the proliferation rate were evaluated. Additionally, fluorescence intensity of PKH26 labeling at different passage times was quantified. There were no detectable differences in cell morphology, cell growth, and proliferation rate after PKH26 labeling. In addition, fluorescence intensity of PKH26 labeling was gradually reduced with increase of the passage times. The PKH26 labeling disappeared after passage six times. In summary, PKH26 labeling is a safe and ef...

2011-01-01

379

Ocean teleconnections between Antarctica and the Equatorial Pacific and Atlantic.  

Environmental Research Database

Objectives(i) Investigate the correlation between Antarctic sea-ice and equatorial sea-surface temperature anomalies in a realistically forced ocean model simulation of the last 50 years. (ii) Determine whether and how the enormous seasonal change in distribution of sea-ice modifies the seasonal cycle at the Equator. (iii) Determine the detailed pathways of wave propagation both in a historically-forced simulation and in response to realistic perturbations. (iv) Quantify the amplitude of the response i [continued...]DescriptionIt is well known that the equatorial ocean-atmosphere system plays a key role in global climate events such as the El Nino-Southern Oscillation (ENSO) phenomenon. There is now compelling evidence that changes in the Antarctic can strongly and quickly affect the equatorial ocean and the ENSO cycle. Observations demonstrate statistically significant correlations (teleconnections) between the Antarctic and the Equator with leads and lags of ...

2009-01-31

380

Newtonian photorealistic ray tracing of grating cloaks and correlation-function-based cloaking-quality assessment  

CERN Document Server

Grating cloaks are a variation of dielectric carpet (or ground- plane) cloaks. The latter were introduced by Li and Pendry. In contrast to the numerical work involved in the quasi-conformal carpet cloak, the refractive-index profile of a conformal grating cloak follows a closed and exact analytical form. We have previously mentioned that finite-size conformal grating cloaks may exhibit better cloaking than usual finite-size carpet cloaks. In this letter, we directly visualize their performance using photorealistic ray-tracing simulations. We employ a Newtonian approach that is advantageous compared to conventional ray tracing based on Snell's law. Furthermore, we quantify the achieved cloaking quality by computing the cross-correlations of rendered images. The cross-correlations for the grating cloak are much closer to 100% (i.e., ideal) than those for the Gaussian carpet cloak.

2010-01-01

381

Nanoscale calcium bismuth mixed oxide with enhanced photocatalytic performance under visible light  

British Library Electronic Table of Contents (United Kingdom)

The objective of materials research is the development of economical, safe and efficient synthesis routes that lead to the formation of a photocatalyst which is able to overcome performance problems related to particle size, crystallinity, or low surface area. Here, we report high-quality functional nanoparticles of calcium bismuth mixed oxide with 15nm nominal size corresponding to a specific surface area of 41m^2/g which were produced by single-step flame spray synthesis (FSS). The high temperature of the flame afforded creation of oxygen vacancies which were quantified by near edge X-ray absorption fine structure (NEXAFS) spectra. These two parameters, developed active surface area and created in the flame oxygen vacancies, allowed to enhance the photocatalytic activity of calcium bismu...

2010-01-01

382

Modelling the reworking effects of bioturbation on the incorporation of radionuclides into the sediment column: implications for the fate of particle-reactive radionuclides in Irish Sea sediments  

British Library Electronic Table of Contents (United Kingdom)

A microcosm laboratory experiment was conducted to determine the impact of biological reworking by the ragworm Nereis diversicolor on the redistribution of particle-bound radionuclides deposited at the sediment-water interface. Over the course of the 40-day experiment, as much as 35% of a 137Cs-labelled particulate tracer deposited on the sediment surface was redistributed to depths of up to 11 cm by the polychaete. Three different reworking models were employed to model the profiles and quantify the biodiffusion and biotransport coefficients: a gallery-diffuser model, a continuous sub-surface egestion model and a biodiffusion model. Although the biodiffusion coefficients obtained for each model were quite similar, the continuous sub-surface egestion model provided the best fit to the data...

2010-01-01

383

Modeling dispersion and deposition of smoke generated from chemical fires  

British Library Electronic Table of Contents (United Kingdom)

Abstract Smoke is a mixture of toxic gases and suspended particulate matter of solids and liquids that evolves from a fire of flammable materials. This article presents real-time consequence modeling to track the concentration of individual species in smoke as well as its soot deposition. In the modeling process presented, the burning rate or vapor mass is fed into a combustion model in which the combustion of products has been identified and quantified along with the temperature of the fire. The output of the combustion model is the smoke that will be dispersed into the ambient. The fire geometry, which depends on the type of fire (e.g., pool or flare), is identified. A dispersion model with the capability of determining particulate deposition is then used for tracking the smoke plume. Th...

2011-01-01

384

Mineral-wool industry: opportunities for natural gas technologies. Topical report, January-July 1987  

Science.gov (United States)

To quantify the opportunities for natural gas and identify technological advances needed to capture such opportunities, the mineral-wool industry was analyzed with respect to the principal companies, their capabilities, and markets. The mineral-wool industry is stable with a slightly declining market. Of its market segments, only commercial acoustic insulation (which is currently dominant) is likely to be affected by growth in the next ten years. The principal process is based on treatment of blast-furnace slags in a cupola furnace using coke as the fuel and reducing agent. Expanded use of gas, as a substitute for coke, would eliminate environmental problems and expand the latitude of suitable raw materials. The study provides insights into the mineral-wool industry and identifies factors that may constitute bases for future usage of natural gas.

1988-05-01

385

Measuring the scale of segregation in mixing data  

British Library Electronic Table of Contents (United Kingdom)

Abstract Four methods were used to extract length scales from mixing data: the maximum striation thickness, point-to-nearest-neighbour (PNN) distributions, the correlogram and the variogram. Four test data sets were analysed: blending in a micromixer; particle dispersion in a stirred tank; dispersion of a smoke plume and a pulse tracer test in a reactor. The maximum striation thickness captures the largest length scale. The PNN method quantifies differences between clustered, random and regular spatial distributions. The correlogram calculation cannot be consistently used for all types of mixing data and has therefore been rejected. The variogram reveals both large-scale segregation and periodicity. Sub-sampling is needed to isolate smaller structures. The variogram, PNN and transect metho...

2011-01-01

386

Lower order roots more palatable to herbivores: a case study with two temperate tree species  

British Library Electronic Table of Contents (United Kingdom)

Determining which kinds of roots are likely to be consumed by root herbivores may improve our understanding of the mechanistic control on fine root dynamics. Here, we tested the hypothesis that root herbivores prefer to consume the distal lower order roots in their branching networks. Insecticide was applied to soil to quantify effects of root herbivores on root biomass and production in the first five orders (the distal roots numbered as first-order) in Fraxinus mandshurica and Larix gmelinii plantations from May 2008 to July 2009. Root morphology, chemistry, anatomy and physiology were measured simultaneously across branching orders. Among the first five order roots, significant consumptions by herbivores were found only for the two distal lower order roots throughout growing seasons, wi...

2011-01-01

387

Load transfer in bovine plexiform bone determined by synchrotron x-ray diffraction.  

Energy Technology Data Exchange (ETDEWEB)

High-energy synchrotron x-ray diffraction (XRD) has been used to quantify load transfer in bovine plexiform bone. By using both wide-angle and small-angle XRD, strains in the mineral as well as the collagen phase of bone were measured as a function of applied compressive stress. We suggest that a greater proportion of the load is borne by the more mineralized woven bone than the lamellar bone as the applied stress increases. With a further increase in stress, load is shed back to the lamellar regions until macroscopic failure occurs. The reported data fit well with reported mechanisms of microdamage accumulation in bovine plexiform bone.

2008-02-01

388

Large specific absorption rates in the magnetic hyperthermia properties of metallic iron nanocubes  

CERN Document Server

We report on the magnetic hyperthermia properties of chemically synthesized ferromagnetic 11 and 16 nm Fe(0) nanoparticles of cubic shape displaying the saturation magnetization of bulk iron. The specific absorption rate measured on 16 nm nanocubes is 1690+-160 W/g at 300 kHz and 66 mT. This corresponds to specific losses-per-cycle of 5.6 mJ/g, largely exceeding the ones reported in other systems. A way to quantify the degree of optimization of any system with respect to hyperthermia applications is proposed. Applied here, this method shows that our nanoparticles are not fully optimized, probably due to the strong influence of magnetic interactions on their magnetic response. Once protected from oxidation and further optimized, such nano-objects could constitute efficient magnetic cores for biomedical applications requiring very large heating power.

2010-01-01

389

Landscape approach for quantifying land use land cover change (1972?2006) and habitat diversity in a mining area in Central India (Bokaro, Jharkhand)  

British Library Electronic Table of Contents (United Kingdom)

The rate and intensity of land use land cover (LULC) change has increased considerably during the past couple of decades. Mining brings significant alterations in LULC specifically due to its impact on forests. Parts of Central India are well endowed with both forests and minerals. Here, the conflict between human interests and nature has intensified over time. Monitoring and assessment of such conflicts are important for land management and policy making. Remote sensing and Geographical Information System have the potential to serve as accurate tools for environmental monitoring. Understanding the importance of landscape metrics in land use planning is challenging but important. These metrics calculated at landscape, class, and patch level provide an insight into changing spatiotemporal d...

2010-01-01

390

Investigation of the unsteadiness of a shock-reflection interaction with time-resolved particle image velocimetry  

British Library Electronic Table of Contents (United Kingdom)

The spatio-temporal dynamics of an impinging shock/boundary layer interaction at Mach 2 and under incipient separation conditions, has been investigated experimentally by means of high-speed particle image velocimetry (PIV). The available PIV acquisition rate of up to 20 kHz permits a time-resolved characterization of the interaction. The dynamics of different flow regions?notably the separation region and the reflected shock?were quantified by means of temporal auto-correlation fields and pseudo-spectral analysis. The PIV data further enable to investigate the relationship between spatially extended flow features, such as shock position and bubble size, as well as the influence of the upstream boundary layer. The results confirm earlier studies that there is an important upstream effect o...

2011-01-01

391

Interfacial characteristics of wood fiber/polystyrene composites  

Energy Technology Data Exchange (ETDEWEB)

Considerable interest has focused recently on the use of lignocellulosic fibers as a reinforcement for thermoplastic polymers. The combination of these dissimilar materials, however, is characterized by a widespread incompatibility that leads to a weak fiber/polymer interface and poor performance properties for the composite. In an effort to improve compatibility a number of fiber surface modification approaches have been investigated including plasma, ozone, and polymer grafting treatments. Evaluation of adhesion improvements has been complicated by processing variables that are difficult to control. This paper will discuss the use of the-micro-debond test in quantifying the interfacial shear strength (ISS) in wood fiber/polystyrene composites. Wood fibers were modified to different degrees with styrene-maleic anhydride copolymers that varied in their composition. The effect of fiber modification on surface energetics was determined using dynamic contact angle ...

1995-12-01

392

Inflammatory Biomarkers of Sulfur Mustard Analog 2-Chloroethyl Ethyl Sulfide-Induced Skin Injury in SKH-1 Hairless Mice  

British Library Electronic Table of Contents (United Kingdom)

Sulfur mustard (HD) is an alkylating and cytotoxic chemical warfare agent, which inflicts severe skin toxicity and an inflammatory response. Effective medical countermeasures against HD-caused skin toxicity are lacking due to limited knowledge of related mechanisms, which is mainly attributed to the requirement of more applicable and efficient animal skin toxicity models. Using a less toxic analog of HD, chloroethyl ethyl sulfide (CEES), we identified quantifiable inflammatory biomarkers of CEES-induced skin injury in dose- (0.05-2 mg) and time- (3-168 h) response experiments, and developed a CEES-induced skin toxicity SKH-1 hairless mouse model. Topical CEES treatment at high doses caused a significant dose-dependent increase in skin bi-fold thickness indicating edema. Histopathological e...

2009-01-01

393

In vitro acaricidal activity of neem (Azadirachta indica) seed extracts with known azadirachtin concentrations against Rhipicephalus microplus  

British Library Electronic Table of Contents (United Kingdom)

The effect of four extracts from neem seeds (Azadirachta indica) containing 2000, 5000, 9000 and 10,000ppm of azadirachtin A (AZA), quantified by high-performance liquid chromatography (HPLC) and diluted to 1.25%; 2.5%; 5.0%; 10.0% and 12.8% was verified by in vitro tests with engorged females and larvae of the cattle tick Rhipicephalus microplus. The results from the bioassays with the engorged females showed that the main toxic effect of the extracts was reduction of the reproductive parameters, with a sharp drop in the number of eggs laid and the hatching rate, mainly when the extracts were diluted to 10.0% and 12.8%. The product effectiveness (PE) calculations for all the solutions tested showed that the AZA solution at 10,000ppm (N10) was the most effective. However, statistical analy...

2011-01-01

394

Improvements to the RELAP5/MOD3 reflood model and uncertainty quantification of reflood peak clad temperature  

Energy Technology Data Exchange (ETDEWEB)

This research aims to develop reliable, advanced system thermal-hydraulic computer code and to quantify the uncertainties of code to introduce the best estimate methodology of ECCS for LBLOCA. Although the one of best estimate code, RELAP5/MOD3.1 was introduced from USNRC, several deficiencies in its reflood model and some improvements have been made. The improvements consist of modification of reflood wall heat transfer package and adjusting the drop size in dispersed flow regime. The tome smoothing of wall vaporization and level tracking model are also added to eliminate the pressure spike and level oscillation. For the verification of improved model and quantification of associated uncertainty, the FLECHT-SEASET data were used and upper limit of uncertainty at 95% confidence level is evaluated. (Author) 30 refs., 49 figs., 2 tabs.

1994-06-01

395

Impact of Cr3C2/VC addition on the dry sliding friction and wear response of WC-Co cemented carbides  

British Library Electronic Table of Contents (United Kingdom)

Two grades of WC-10wt.%Co cemented carbide with or without addition of Cr3C2/VC grain growth inhibitor during liquid phase sintering were produced with the goal to investigate their reciprocating sliding friction and wear behaviour against WC-6wt.%Co cemented carbide under unlubricated conditions. The tribological characteristics were obtained on a Plint TE77 tribometer using distinctive normal contact loads. The generated wear tracks were analyzed by scanning electron microscopy and quantified topographically using surface scanning equipment. The post-mortem obtained wear volumes were compared to the online assessed wear. Correlations between wear volume, wear rate and coefficient of friction on the one hand and sliding distance and microstructural properties on the other hand were determ...

2009-01-01

396

How Much Does the Midline Incision Add to Urethral Diameter After Tubularized Incised Plate Urethroplasty? An Experimental Animal Study  

British Library Electronic Table of Contents (United Kingdom)

PurposeWe objectively quantified the gain in urethral diameter and the effect of stenting after tubularized incised plate urethroplasty in a rabbit hypospadias model. Materials and MethodsWe created a hypospadias model in 12 New Zealand white male rabbits by excising the ventral urethra. A 3 cm tattoo line was made longitudinally in the dorsal urethral plate midline. Two weeks later a 2 cm relaxing incision was made in the middle part of the tattooed line. The stretched incision width between the tattooed edges was measured, followed by urethral plate tubularization. Six rabbits were stented and 6 were nonstented. Two weeks later the animals were sacrificed and the distance separating the tattoo was measured at the midpoint of the tattooed line. Transverse sections at this point were exami...

2011-01-01

397

Heat loss from an open cavity  

Energy Technology Data Exchange (ETDEWEB)

Cavity type receivers are used extensively in concentrating solar thermal energy collecting systems. The Solar Total Energy Project (STEP) in Shenandoah, Georgia is a large scale field test for the collection of solar thermal energy. The STEP experiment consists of a large field array of solar collectors used to supplement the process steam, cooling and other electrical power requirements of an adjacent knitwear manufacturing facility. The purpose of the tests, conducted for this study, was to isolate and quantify the radiative, conductive, and convective components of total heat loss, and to determine the effects of operating temperature, receiver angle, and aperture size on cavity heat loss. An analytical model for radiative heat loss was developed and compared with two other methods used to determine radiative heat loss. A proposed convective heat loss correlation, including effects of aperture size, receiver operating temperature, and receiver angle is ...

1995-12-01

398

Health risks arising from ionizing radiation and chemical pollutants  

International Nuclear Information System (INIS)

In quantifying health risks arising from radiation exposure and synergistic effects promoted by radiation the dose-effect relationship must be used as a basis. Special problems arise in the extrapolation of experimental results or in the treatment of data in the region of low doses administered over long periods of time. For radiation protection purposes, especially manifestations of cancer and genetic effects are significant. The International Commission on Radiation Protection has published binding guiding values on the basis of which to assess the risk of cancer. The cancer risk and genetic risks are estimated for relevant dose ranges and compared with other factors of civilization. For the most important chemical pollutants emitted into the environment the possibilities of impacts arising from synergistic effects are discussed on the basis of the rules and regulations specified in German antipollution legislation. (orig.) 891 HP/orig. 892 MKO.

1979-10-03

399

Geospatial tools for assessing land degradation in Budgam district, Kashmir Himalaya, India  

British Library Electronic Table of Contents (United Kingdom)

Land degradation reduces the ability of the land to perform many biophysical and chemical functions. The main aim of this study was to determine the status of land degradation in the Budgam area of Kashmir Himalaya using remote sensing and geographic information system. The satellite data together with other geospatial datasets were used to quantify different categories of land degradation. The results were validated in the field and an accuracy of 85% was observed. Land use/land cover of the study area was determined in order to know the effect of land use on the rate of land degradation. Normalized differential vegetation index (NDVI) and slope of the area were determined using LANDSAT-enhanced thematic mapper plus (ETM+) data, advanced space borne thermal emission and reflection radiome...

2011-01-01

400

Genetic diversity among Angus, American Brahman, Senepol and Romosinuano cattle breeds:  

British Library Electronic Table of Contents (United Kingdom)

Summary The objective of this study was to quantify the genetic diversity among breeds under evaluation for tropical adaptability traits that affect the performance of beef cattle at the USDA/ARS SubTropical Agricultural Research Station (STARS) near Brooksville, FL, USA. Twenty-six microsatellite loci were used to estimate parameters of genetic diversity among the breeds American Brahman, Angus, Senepol and Romosinuano; the latter was comprised of two distinct bloodlines (Costa Rican and Venezuelan). Genotypes of 47 animals from each of these STARS herds were analysed for genetic diversity and genetic distance. Using two methods, the greatest genetic distance was detected between the Costa Rican line of Romosinuano and the Senepol. Gene diversity ranged between 0.64 (Costa Rican line of R...

2007-01-01

401

Fuel-cycle cost comparisons with oxide and silicide fuels  

Energy Technology Data Exchange (ETDEWEB)

This paper addresses fuel cycle cost comparisons for a generic 10 MW reactor with HEU aluminide fuel and with LEU oxide and silicide fuels in several fuel element geometries. The intention of this study is to provide a consistent assessment of various design options from a cost point of view. Fuel cycle cost benefits could result if a number of reactors were to utilize fuel elements with the same number or different numbers of the same standard fuel plate. Data are presented to quantify these potential cost benefits. This analysis shows that there are a number of fuel element designs using LEU oxide or silicide fuels that have either the same or lower total fuel cycle costs than the HEU design. Use of these fuels with the uranium densities considered requires that they are successfully demonstrated and licensed.

1982-01-01

402

Forecasting the growth of China’s natural gas consumption  

British Library Electronic Table of Contents (United Kingdom)

The use of natural gas in China is still relatively immature, as gas production only supplies a low percentage of the domestic energy system. In contrast, Chinese economy mainly relies on coal with a 67% share of the total primary energy supply. The environmental impact from this high coal dependence is significant and planners have sought for cleaner energy sources. Natural gas is both cleaner and generally more efficient than coal and gas consumption is rising quickly due to these facts. The growth tendency indicates that natural gas will become an important substitution for coal in some parts of the Chinese primary energy consumption. To quantify this tendency, this paper uses a system dynamics model to create a possible outlook. The results show that the gas consumption in China will c...

2011-01-01

403

Fixation of high-level wastes in glasses  

Energy Technology Data Exchange (ETDEWEB)

A plant for the fixation of high-level wastes in borosilicate glass has been operating in France since 1978. A large plant is under construction in the U.S. for the fixation of defence high-level waste and plans for other glass fixation plants are well advanced at several sites around the world. Among the reasons for the selection of borosilicate glass as a fixation medium are the relative ease of processing wastes of variable composition by means of well established technology, and the long-term radiation and thermal stability of the glass. Well formulated glass also has sufficient resistance to the action of groundwater so that it can serve as an important barrier against the spread of radionuclides via groundwater in any forseeable situation. Research is continuing to quantify the reactions of waste glass in site-specific geological repository environments.

1986-07-30

404

Financial evaluation of renewable energy technologies for irrigation water pumping in India  

International Nuclear Information System (INIS)

An attempt to develop a simple framework for financial evaluation of renewable energy technologies (RETs) such as photovoltaic (PV) pump, windmill pump, biogas and producer gas-driven dual fuel engine pumps for irrigation water pumping has been made. The unit cost of water and unit cost of useful energy delivered by the RETs have been estimated. The monetary benefits that accrued to the end-user have been quantified in terms of the amount of diesel or electricity saved. Financial figures of merit for the investments made in the RETs have been estimated. The effect of fuel price escalation on these measures of financial performance has also been evaluated along with the estimation of the break-even prices of fuels likely to be substituted by RETs. Results of some exemplifying calculations are presented and briefly discussed.

2007-06-01

405

Extremal behavior of a coupled continuous time random walk  

British Library Electronic Table of Contents (United Kingdom)

Coupled continuous time random walks (CTRWs) model normal and anomalous diffusion of random walkers by taking the sum of random jump lengths dependent on the random waiting times immediately preceding each jump. They are used to simulate diffusion-like processes in econophysics such as stock market fluctuations, where jumps represent financial market microstructure like log returns. In this and many other applications, the magnitude of the largest observations (e.g. a stock market crash) is of considerable importance in quantifying risk. We use a stochastic process called a coupled continuous time random maxima (CTRM) to determine the density governing the maximum jump length of a particle undergoing a CTRW. CTRM are similar to continuous time random walks but track maxima instead of sums....

2011-01-01

406

Exergoeconomic analysis of the power generation system using blast furnace and coke oven gas in a Brazilian steel mill  

British Library Electronic Table of Contents (United Kingdom)

The rational use of energy has become a priority for all industries in Brazil, mainly after the energy rationing in 2001. Methodologies to quantify and improve the performance of plants that consume and generate electricity and thermal energy are being used to reach this goal. Exergoeconomic analysis provides a complete diagnosis of a plant, both in exergetic and in monetary values. This study shows the methodology used to assess the power generation system of the Companhia Siderurgica Tubarao (CST). The current system is based on a regenerative Rankine cycle using two gases from steel production - blast furnace gas (BFG) and coke oven gas (COG) - to generate electric power and occasionally steam for the process. Use of the Theory of Exergetic Cost allowed determination of monetary and exe...

2009-01-01

407

Evaluation of Capiox FX05 Oxygenator With an Integrated Arterial Filter on Trapping Gaseous Microemboli and Pressure Drop With Open and Closed Purge Line  

British Library Electronic Table of Contents (United Kingdom)

Abstract Gaseous microemboli (GME) remain a challenge for cardiopulmonary bypass (CPB) because there is a positive correlation between microemboli exposure during CPB and postoperative neurological injury. Thus, minimizing the number of GME delivered to pediatric patients undergoing CPB procedures would lead to better clinical outcomes. In this study, we used a simulated CPB model to evaluate the effectiveness of capturing GME and the degree of membrane pressure drop for a new membrane oxygenator, Capiox Baby FX05 (Terumo Corporation, Tokyo, Japan), which has an integrated arterial filter with open and closed purge line. We used identical components in this study as our clinical CPB circuit. Three emboli detection and classification quantifier transducers were placed at prepump, preoxygena...

2010-01-01

408

Estimation and characterization of PCDD/Fs and dioxin-like PCBs from Chinese iron foundries  

British Library Electronic Table of Contents (United Kingdom)

The iron foundry industry is considered to be a potential source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study investigated the emission factors and total emission amounts of PCDD/Fs and dioxin-like polychlorinated biphenyls (DL-PCBs) from iron foundries in China. The concentrations and the World Health Organization toxicity equivalents (WHO-TEQs) are presented and the congener profiles are discussed in this paper. In the present work, 26 fly ash samples were collected and tested to quantify the PCDD/Fs and DL-PCBs generated by 14 plants of different scales, and five stack gas samples were collected from two (named as EFG and LFG) of those plants. The emission levels of PCDD/Fs and DL-PCBs indicated that hot-air cupolas had lower emissions than cold-air cupol...

2011-01-01

409

Estimating aboveground biomass in forest and oil palm plantation in Sabah, Malaysian Borneo using ALOS PALSAR data  

British Library Electronic Table of Contents (United Kingdom)

Conversion of tropical forests to oil palm plantations in Malaysia and Indonesia has resulted in large-scale environmental degradation, loss of biodiversity and significant carbon emissions. For both countries to participate in the United Nation's REDD (Reduced Emission from Deforestation and Degradation) mechanism, assessment of forest carbon stocks, including the estimated loss in carbon from conversion to plantation, is needed. In this study, we use a combination of field and remote sensing data to quantify both the magnitude and the geographical distribution of carbon stock in forests and timber plantations, in Sabah, Malaysia, which has been the site of significant expansion of oil palm cultivation over the last two decades. Forest structure data from 129ha of research and inventory p...

2011-01-01

410

Estimating Field Volatility of Soil Fumigants Using CHAIN_2D: Mitigation Methods and Comparison Against Chloropicrin and 1,3-Dichloropropene Field Observations  

British Library Electronic Table of Contents (United Kingdom)

Academic, government, and industrial field researchers have generated a significant database of field studies of the volatility of soil applied fumigants. However, limited work exists in validating physical models against field volatility data sets and fully exploring the volatility parametric response surface. Field studies quantifying atmospheric flux for soil fumigants 1,3-dichloropropene and chloropicrin are validated against the United States Department of Agriculture (USDA Salinity Laboratory) soil physics model CHAIN_2D that was modified specifically for agronomic uses of soil fumigants. Comparison between model predictions and field observations for six unique field trials in five different states indicate that CHAIN_2D effectively captures the magnitude and duration of fumigant em...

2010-01-01

411

Environmental assessment of proposed effluent limitations guidelines and standards for the transportation equipment cleaning category: Volume 1. Final report  

Science.gov (United States)

This environmental assessment quantifies the water quality-related benefits for Transportation Equipment Cleaning (TEC) facilities based on site-specific analyses of current conditions and the conditions that would be achieved by process changes under proposed BAT (Best Available Technology) and PSES (Pretreatment Standards for Existing Sources) controls. The US Environmental Protection Agency (EPA) estimated instream pollutant concentrations for 157 priority and nonconventional pollutants from three subcategories (barge-chemical and petroleum, rail-chemical, and truck-chemical) of direct and indirect discharges using stream dilution modeling. The potential impacts and benefits to aquatic life are projected by comparing the modeled instream pollutant concentrations to published EPA aquatic life criteria guidance or to toxic effect levels.

1998-05-01

412

Elemental analysis of savannah grass' burning ashes  

International Nuclear Information System (INIS)

In order to quantify the biomass burning emissions, the main atmospheric pollution source of tropical and subtropical regions, we carried out the analysis of ashes that are also formed during these fires. To this end, we developed analytical methods to characterize the composition of savannah grass burning ashes by using X-ray fluorescence for mineral elements and microanalysis for C, H, O and N. Samples used in this work have been collected during laboratory combustion experiments, with chemically well-defined natural savannah grasses from Ivory Coasts and South Africa. The reproducibility and efficiency of different developed procedures have been studies. The analytical relative precision is generally better than 5%. This development has allowed to establish, for the first time, the global mass balance of ashes resulting from savannah grass burning. (authors). 16 refs., 3 figs., 8 tabs.

413

Dosimetric considerations for patients with HIP prostheses undergoing pelvic irradiation. Report of the AAPM Radiation Therapy Committee Task Group 63  

International Nuclear Information System (INIS)

This document is the report of a task group of the Radiation Therapy Committee of the AAPM and has been prepared primarily to advise hospital physicists involved in external beam treatment of patients with pelvic malignancies who have high atomic number (Z) hip prostheses. The purpose of the report is to make the radiation oncology community aware of the problems arising from the presence of these devices in the radiation beam, to quantify the dose perturbations they cause, and, finally, to provide recommendations for treatment planning and delivery. Some of the data and recommendations are also applicable to patients having implanted high-Z prosthetic devices such as pins, humeral head replacements. The scientific understanding and methodology of clinical dosimetry for these situations is still incomplete. This report is intended to reflect the current state of scientific understanding and technical methodology in clinical dosimetry for radiation oncology patients ...

2003-06-01

414

Digital Audio Sampling for Film and Video.  

Science.gov (United States)

Digital audio sampling is explained, and some of its implications in digital sound applications are discussed. Digital sound equipment is rapidly replacing analog recording devices as the state-of-the-art in audio technology. The philosophy of digital recording involves doing away with the continuously variable analog waveforms and turning the patterns into numbers. A digital recording device rapidly samples the incoming sounds, quantifying the signal into a series of numerical values (binary codes). Although digital sound eliminates many of the traditional analog problems, digital signal processing presents key problems in sampling rates and synchronization. Careful control is necessary to check signals through each step in the audio chain. The advantages of digital audio processing include increased signal-to-noise ratio, no flutter, transparent generation of copies, and sound manipulation. These benefits come with increased quality control requirements. One ...

1993-03-01

415

Development of an internet based system for modeling biotin metabolism using Bayesian networks  

British Library Electronic Table of Contents (United Kingdom)

Biotin is an essential water-soluble vitamin crucial for maintaining normal body functions. The importance of biotin for human health has been under-appreciated but there is plenty of opportunity for future research with great importance for human health. Currently, carrying out predictions of biotin metabolism involves tedious manual manipulations. In this paper, we report the development of BiotinNet, an internet based program that uses Bayesian networks to integrate published data on various aspects of biotin metabolism. Users can provide a combination of values on the levels of biotin related metabolites to obtain the predictions on other metabolites that are not specified. As an inherent feature of Bayesian networks, the uncertainty of the prediction is also quantified and reported to...

2011-01-01

416

Density separation of combustion-derived soot and petrogenic graphitic black carbon: Quantification and isotopic characterization  

Energy Technology Data Exchange (ETDEWEB)

The black carbon continuum is composed of a series of carbon-rich components derived from combustion or metamorphism and characterized by contrasting environmental behavior and susceptibility to oxidation. In this work, we present a micro-scale density fractionation method that allows isolating the small quantities of soot-like and graphitic material usually found in natural samples. Organic carbon and {delta}{sup 13}C mass balance calculations were used to quantify the relative contributions of the two fractions to thermally-stable organic matter from a series of aquatic sediments. Varying proportions of soot-like and graphitic material were found in these samples, with large variations in {delta}{sup 13}C signatures suggesting important differences in their origin and/or dynamics in the environment.

2009-01-01

417

Cryo-irradiation as a terminal method for the sterilization of drug aqueous solutions  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study is to evaluate the specificities of the irradiation of drugs in frozen aqueous solution. The structures of the degradation products were determined to gain insight into the radiolysis mechanisms occurring in frozen aqueous solutions. Metoclopramide hydrochloride and metoprolol tartrate were chosen as models. The frozen solutions were irradiated at dry ice temperature by high energy electrons at various doses. The drug purity (chemical potency) and the radiolysis products were quantified by HPLC-DAD. Characterization of the degradation products was performed by LC-APCI-MS-MS. The structures of the radiolysis products detected in irradiated frozen aqueous solutions were compared to those detected in solid-state and aqueous solutions (previous studies). For both metoclop...

2008-01-01

418

Cosmological Information from Lensed CMB Power Spectra  

CERN Document Server

Gravitational lensing distorts the cosmic microwave background (CMB) temperature and polarization fields and encodes valuable information on distances and growth rates at intermediate redshifts into the lensed power spectra. The non-Gaussian bandpower covariance induced by the lenses is negligible to l=2000 for all but the B polarization field where it increases the net variance by up to a factor of 10 and favors an observing strategy with 3 times more area than if it were Gaussian. To quantify the cosmological information, we introduce two lensing observables, characterizing nearly all of the information, which simplify the study of non-Gaussian impact, parameter degeneracies, dark energy models, and complementarity with other cosmological probes. Information on the intermediate redshift parameters rapidly becomes limited by constraints on the cold dark matter density and initial amplitude of fluctuations as observations improve. Extraction of this information ...

2006-01-01

419

Correlation, hierarchies, and networks in financial markets  

CERN Document Server

We discuss some methods to quantitatively investigate the properties of correlation matrices. Correlation matrices play an important role in portfolio optimization and in several other quantitative descriptions of asset price dynamics in financial markets. Specifically, we discuss how to define and obtain hierarchical trees, correlation based trees and networks from a correlation matrix. The hierarchical clustering and other procedures performed on the correlation matrix to detect statistically reliable aspects of the correlation matrix are seen as filtering procedures of the correlation matrix. We also discuss a method to associate a hierarchically nested factor model to a hierarchical tree obtained from a correlation matrix. The information retained in filtering procedures and its stability with respect to statistical fluctuations is quantified by using the Kullback-Leibler distance.

2008-01-01

420

Continuous Paranematic-to-Nematic Ordering Transitions of Liquid Crystals in Tubular Silica Nanochannels  

CERN Document Server

The optical birefringence of rod-like nematogens (7CB, 8CB), imbibed in parallel silica channels with 10 nm diameter and 300 micrometer length, is measured and compared to the thermotropic bulk behavior. The orientational order of the confined liquid crystals, quantified by the uniaxial nematic ordering parameter, evolves continuously between paranematic and nematic states, in contrast to the discontinuous isotropic-to-nematic bulk phase transitions. A Landau-de Gennes model reveals that the strength of the orientational ordering fields, imposed by the silica walls, is beyond a critical threshold, that separates discontinuous from continuous paranematic-to-nematic behavior. Quenched disorder effects, attributable to wall irregularities, leave the transition temperatures affected only marginally, despite the strong ordering fields in the channels.

2008-01-01

421

Consumer welfare effects of increased food and energy prices  

British Library Electronic Table of Contents (United Kingdom)

In this study, the authors evaluated how much price changes in food and energy - two basic living expenditures competing for consumers' budgets - would affect consumer welfare. We first estimated a US complete demand system to quantify the interdependent demand relationships among 11 categories of consumption expenditures. Among the estimates, the own price elasticities of both food and energy are relatively inelastic, a finding that explains the dynamics of the recent soaring food and energy prices. The estimated demand elasticities were then incorporated into the measurement of Hicksian compensating variation to analyse the consumer welfare effects of price changes in food and energy. The results indicated that an increase in food and energy prices would increase compensated expenditures...

2012-01-01

422

Competitive and allelopathic interference between soybean crop and annual wormwood (Artemisia annua L.) under field conditions  

British Library Electronic Table of Contents (United Kingdom)

Annual wormwood interference on soybean crop growth and yield may result from competition and allelopathy, which are modulated by crop management. Allelochemicals released by annual wormwood (e.g. artemisinin) may affect the crop directly or indirectly through the effect on the nitrogen fixing symbiont, Bradyrhizobium japonicum. The objectives were (i) to quantify the crop response (i.e. biomass production, nodulation and yield) to weed interference and (ii) to determinate the relative change of competition and allelopathy interferences, when a sublethal dose of herbicide is applied. Two split plot field experiments with three replications were used. The experiment involved a factorial combination of five weed-crop density (soybean/annual wormwood, plantsm^-^2) levels: D1, pure soybean, 40...

2011-01-01

423

Competitive adsorption of binary mixture of Leptospirillum ferriphilum and Acidithiobacillus caldus onto pyrite  

British Library Electronic Table of Contents (United Kingdom)

Leptospirillum ferriphilum and Acidithiobacillus caldus are two important acidophilic microorganisms involved in iron and sulfur oxidation during bioleaching. Cell adsorption to mineral surfaces is important for the direct leaching or contact leaching of minerals. In this study, we report the competitive adsorption of binary mixtures of L. ferriphilum LF-104 and A. caldus MTH-04 onto pyrite surfaces. The Langmuir adsorption parameter (CAm) indicated that these two bacteria underwent competitive adsorption to pyrite. Real-time quantitive PCR was used to quantify the relative amounts of L. ferriphilum and A. caldus adsorbed onto the surfaces of pyrite following exposure to a mixture of these two organisms. The adsorption of L. ferriphilum was not affected by A. caldus. However, adsorption of...

2010-01-01

424

Competitive abilities of native grasses and non-native (Bothriochloa spp.) grasses  

British Library Electronic Table of Contents (United Kingdom)

Old World Bluestems (OWB), introduced from Europe and Asia in the 1920s, recently have begun to raise concerns in the Great Plains. Despite suggestion in the late 1950s that OWB were weedy and negatively impacted biological diversity, they were widely introduced throughout the Great Plains for agricultural purposes. Anecdotal evidence suggests that OWB exhibit invasive characteristics that promote competitive exclusion of native species. The objective of our study was to quantify the competitive abilities of two OWB species (Caucasian bluestem; Bothriochloa bladhii (Retz.) S.T. Blake (=?Bothriochloa caucasica (Trin.) C.E. Hubb.) and yellow bluestem; Bothriochloa ischaemum (L.) Keng) with three native grass species (big bluestem (Andropogon gerardii Vitman), little bluestem (Schizachyrium s...

2008-01-01

425

Comparisons of the SCDAP computer code with bundle data under severe accident conditions  

International Nuclear Information System (INIS)

The SCDAP computer code, which is being developed under the sponsorship of the United States Nuclear Regulatory Commission, models the progression of light water reactor core damage including core heatup, core disruption and debris formation, debris heatup, and debris melting. SCDAP is being used to help identify and understand the phenomena that control core behavior during a severe accident, to help quantify uncertainties in risk assessment analysis, and to support planning and interpretation of severe fuel damage experiments and data. Comparisons between SCDAP calculations and the experimental data showed good agreement. Calculated and measured bundle temperatures for SFD-ST were within 200 K for the entire bundle and within 20 K for maximum cladding temperatures. For ESSI-2, calculated and measured maximum cladding temperatures were within 50 K, and the extensive liquefaction and relocation that was calculated was in agreement with experimental results.

1983-08-22

426

Combined In Vivo/In Silico Study of Mechanobiological Mechanisms During Endochondral Ossification in Bone Healing  

British Library Electronic Table of Contents (United Kingdom)

Mechanobiological theories have been introduced to illustrate the interaction between biology and the local mechanical environment during bone healing. Although several theories have been proposed, a quantitative validation using histomorphometric data is still missing. In this study, in vivo histological data based on an ovine animal experiment was quantified and used to validate bone healing simulations focussing on the endochondral ossification process. The bone formation at different callus regions (periosteal and endosteal bone at the medial and lateral side) was analyzed from in vivo data and quantitatively compared with in silico results. A histomorphometric difference was found in medial and lateral hard callus formation 3 weeks after osteotomy. However, the same amount of new bone...

2011-01-01

427

Chemical, electrical and electrochemical characterization of hybrid organic/inorganic polypyrrole/PW12O40^3^- coating deposited on polyester fabrics  

British Library Electronic Table of Contents (United Kingdom)

A study of the stability of conducting fabrics of polyester (PES) coated with polypyrrole/PW12O40^3^- (organic/inorganic hybrid material) in different pH solutions (1, 7, 13) has been done. Washing tests were also done in views of its possible application in electronic textiles such as antistatic clothing. X-ray photoelectron spectroscopy (XPS) studies have been done to quantify the amount of counter ion that remains in the polymer matrix and determine the doping ratio (N^+/N) after the different tests. Scanning electron microscopy (SEM) was also used to observe morphological differences after the different tests. Surface resistivity changes were measured by means of electrochemical impedance spectroscopy (EIS). Scanning electrochemical microscopy (SECM) was employed to measure changes in ...

2011-01-01

428

Changes in Soil Properties and Vegetable Growth in Preparation for Organic Farming in Hawaii  

British Library Electronic Table of Contents (United Kingdom)

Changes in soil properties and vegetable growth were quantified on a low-fertility tropical soil. Four treatments (two composts, urea, and control) were applied to an Oxisol (Rhodic Haplustox, Wahiawa series) in a field on Oahu, Hawaii. Chinese cabbage (Brassica rapa, Chinensis group) and eggplant (Solanum melongena) were grown sequentially as test crops. Soil quality as measured by hot-water-soluble carbon, dehydrogenase activity, and cation exchange capacity (CEC) increased by compost amendments. Total organic carbon or carbon dioxide (CO2) respiration rate did not correlate with the soil amendments. Nitrogen (N) nutrition was the main factor that improved growth and carotenoid content in cabbage. The urea treatment promoted better growth in cabbage, whereas good-quality compost, made of...

2011-01-01

429

Biological treatment of wine of distilleries  

International Nuclear Information System (INIS)

The potential of the yeast Candida tropicalis and Candida guillermondii was evaluated and an isolated partnership of microorganisms of waters of the Medellin River, conformed by two bacteria and one leavening, to degrade the content of organic matter present in wine produced by the factory of Licores and Alcoholes de Antioquia (FLA) in aerobic process with biomass production. For each one of the microorganisms in study this capacity of removal in units of chemical demand of oxygen was quantified (CDO); in addition, parameters were analyzed such as yield of the biomass in relation to the removed CDO and to total reducing sugars (TRS) consumed, time of fermentation and speed of growth different dilutions from wine. Also the possible inhibition was analyzed that the present phenolic compounds in this wine can cause in the biological process of degradation.

430

Assessment of cardio-respiratory interactions in preterm infants by bivariate autoregressive modeling and surrogate data analysis  

British Library Electronic Table of Contents (United Kingdom)

Background: Cardio-respiratory interactions are weak at the earliest stages of human development, suggesting that assessment of their presence and integrity may be an important indicator of development in infants. Despite the valuable research devoted to infant development, there is still a need for specifically targeted standards and methods to assess cardiopulmonary functions in the early stages of life. We present a new methodological framework for the analysis of cardiovascular variables in preterm infants. Our approach is based on a set of mathematical tools that have been successful in quantifying important cardiovascular control mechanisms in adult humans, here specifically adapted to reflect the physiology of the developing cardiovascular system.Methods: We applied our methodology ...

2011-01-01

431

Assessing the performance and benefits of customer distributed generation developers under uncertainties  

British Library Electronic Table of Contents (United Kingdom)

In this paper, the performance of customer-owned distributed generation (DG) units is quantified from different perspectives through an uncertainty study. A Monte Carlo-based method is applied to assess the stochastic operation of the customer-owned DG units in the power distribution system. Several cases are studied to analyze the impact on system performance of using such generators, with the emphasis on benefits. The results of the studied cases show that proper operation of customer-owned DG units placed close to significant consumption centers offers several benefits which lead to significant energy savings and improvement in the performance indices while maintaining the cost-effectiveness. Furthermore, based on the energy demand, different electricity price scenarios considering a co...

2011-01-01

432

Analysis of the bullwhip effect in multi-product, multi-stage supply chain systems-a simulation approach  

British Library Electronic Table of Contents (United Kingdom)

This research aims to develop a simulation approach based on system dynamics modelling (SDM) and adaptive network based fuzzy inference system (ANFIS) for quantifying and reducing the bullwhip effect in a multi-product, multi-stage supply chain. The proposed model is comprised of three groups of variables influencing the bullwhip effect, namely the structure of a supply chain network, supply chain contributions (ordering process in regular situation or when a supplier has a promotion or shortage gaming) and supply chain performances (the number of defects and ordering lead time). As a result, a two layer simulation model is developed with three generic models. The flexibility of this proposed approach is its ability to model various types of ordering policies which are basic inventory poli...

2010-01-01

433

Alternative biosphere modeling for safety assessment of HLW disposal taking account of geosphere-biosphere interface of marine environment  

International Nuclear Information System (INIS)

In the safety assessment of a high-level radioactive waste (HLW) disposal system, it is required to estimate radiological impacts on future human beings arising from potential radionuclide releases from a deep repository into the surface environment. In order to estimated the impacts, a biosphere model is developed by reasonably assuming radionuclide migration processes in the surface environment and relevant human lifestyles. It is important to modify the present biosphere models or to develop alternative biosphere models applying the biosphere models according to quality and quantify of the information acquired through the siting process for constructing the repository. In this study, alternative biosphere models were developed taking geosphere-biosphere interface of marine environment into account. Moreover, the flux to dose conversion factors calculated by these alternative biosphere models was compared with those by the present basic biosphere models. (author)

2001-01-01

434

Achieving a vanishing SNR-gap to exact lattice decoding at a subexponential complexity  

CERN Document Server

The work identifies the first lattice decoding solution that achieves, in the general outage-limited MIMO setting and in the high-rate and high-SNR limit, both a vanishing gap to the error-performance of the (DMT optimal) exact solution of preprocessed lattice decoding, as well as a computational complexity that is subexponential in the number of codeword bits. The proposed solution employs lattice reduction (LR)-aided regularized (lattice) sphere decoding and proper timeout policies. These performance and complexity guarantees hold for most MIMO scenarios, all reasonable fading statistics, all channel dimensions and all full-rate lattice codes. In sharp contrast to the above manageable complexity, the complexity of other standard preprocessed lattice decoding solutions is shown here to be extremely high. Specifically the work is first to quantify the complexity of these lattice (sphere) decoding solutions and to prove the surprising result that the complexity ...

2011-01-01

435

A probabilistic approach to the estimation of lifetime distribution of Alloy 800 SG tubing  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of degradation on reliability of SG tubing. (author)

2008-07-01

436

A probabilistic approach to the estimation of lifetime distribution of Alloy 800 SG tubing  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of degradation on reliability of SG tubing. (author)

2008-06-01

437

A hybrid approach based on SERVQUAL and fuzzy TOPSIS for evaluating transportation service quality  

British Library Electronic Table of Contents (United Kingdom)

Managing service quality is vital to retain customer satisfaction and augment revenues for any business organization. Often it is difficult to assess service quality due to lack of quantifiable measures and limited data. In this paper, we present a hybrid approach based on SERVQUAL and fuzzy TOPSIS for evaluating service quality of urban transportation systems. The proposed approach consists of three steps. The first step involves development of a SERVQUAL based questionnaire to collect data for measuring transportation service quality. The participants provide linguistic assessments to rate the service quality criteria and the alternatives. In step 2, the linguistic ratings are combined through fuzzy TOPSIS to generate an overall performance score for each alternative. The alternative wit...

2011-01-01

438

The application of ecosystems services criteria for green building assessment  

Energy Technology Data Exchange (ETDEWEB)

In the discussion of environmental architecture, we are conjoining two disciplines, the subject of architecture and that of ecology. At their best, green buildings are examples of applied ecology, where designers understand the constitution, organization, and structure of ecosystems, and the impacts of architecture are considered from an environmental perspective. By utilizing the concepts, methods, and language of ecology, designers can create architecture that intentionally engages the natural systems of a site. The establishment of assessment criteria implies the definition of building design criteria. If we establish criteria that are based on our best scientific understanding of environmental capacity, we will begin to develop a building stock that is sustainable. To do this we must quantify the link between the resulting environmental impacts and their cause in building production and use. This is not done in traditional building environmental impact ...

2004-10-01

439

Station set residual : event classification using historical distribution of observing stations.  

Science.gov (United States)

Analysts working at the International Data Centre in support of treaty monitoring through the Comprehensive Nuclear-Test-Ban Treaty Organization spend a significant amount of time reviewing hypothesized seismic events produced by an automatic processing system. When reviewing these events to determine their legitimacy, analysts take a variety of approaches that rely heavily on training and past experience. One method used by analysts to gauge the validity of an event involves examining the set of stations involved in the detection of an event. In particular, leveraging past experience, an analyst can say that an event located in a certain part of the world is expected to be detected by Stations A, B, and C. Implicit in this statement is that such an event would usually not be detected by Stations X, Y, or Z. For some well understood parts of the world, the absence of one or more 'expected' stations - or the presence of one or more 'unexpected' ...

2010-04-01

440

Quantifying the Reactive Uptake of OH by Organic Aerosols in aContinuous Flow Stirred Tank Reactor  

Energy Technology Data Exchange (ETDEWEB)

Here we report a new method for measuring the heterogeneous chemistry of submicron organic aerosol particles using a continuous flow stirred tank reactor. This approach is designed to quantify the real time heterogeneous kinetics, using a relative rate method, under conditions of low oxidant concentration and long reaction times that more closely mimic the real atmosphere. A general analytical expression, which couples the aerosol chemistry with the flow dynamics in the chamber is developed and applied to the heterogeneous oxidation of squalane particles by hydroxyl radicals (OH) in the presence of O2. The particle phase reaction is monitored via photoionization aerosol mass spectrometry and yields a reactive uptake coefficient of 0.51+-0.10, using OH concentrations of 1-7x108 molec cdot cm-3 and reaction times of 1.5+-3 hours. This uptake coefficient is larger than that found for the reaction carried out under high OH concentrations (~;;1x1010 molec cdot cm-3) and ...

2009-03-01

441

Neutron-computer tomography using real-time neutron radiography  

Energy Technology Data Exchange (ETDEWEB)

A real-time neutron radiography facility was constructed including the capability of neutron tomography. The neutron beam was measured for total neutron flux ((1.0 +/- 0.2) x 10/sup 11/ m/(m/sup 2/-sec)), gold cadmium ratio (52 +/- 3) and effective neutron temperature (83/sup 0/C +/- 8/sup 0/C). The angular divergence or nonparallelism of the neutron beam was measured to be 2.3/sup 0/ +/- 0.1/sup 0/ thereby providing a means of quantifying the collimator effectiveness. The resolution capabilities of both static film and real-time neutron radiographs were quantified using a Fourier transform algorithm to calculate the modulation transfer function of both types of radiographs. The contrast sensitivity of both types of radiographs. The contrast sensitivity of both types of radiographs was measured as 3.1% for film and 4.0% for real-time radiographs. Two tomography algorithms, the simultaneous iterative reconstruction technique (SIRT) and the ...

1986-01-01

442

Neutron-computer tomography using real-time neutron radiography  

International Nuclear Information System (INIS)

A real-time neutron radiography facility was constructed including the capability of neutron tomography. The neutron beam was measured for total neutron flux ((1.0 +/- 0.2) x 10"1"1 m/(m"2-sec)), gold cadmium ratio (52 +/- 3) and effective neutron temperature (83"0C +/- 8"0C). The angular divergence or nonparallelism of the neutron beam was measured to be 2.3"0 +/- 0.1"0 thereby providing a means of quantifying the collimator effectiveness. The resolution capabilities of both static film and real-time neutron radiographs were quantified using a Fourier transform algorithm to calculate the modulation transfer function of both types of radiographs. The contrast sensitivity of both types of radiographs. The contrast sensitivity of both types of radiographs was measured as 3.1% for film and 4.0% for real-time radiographs. Two tomography algorithms, the simultaneous iterative reconstruction technique (SIRT) and the convolution method, were ...

1986-01-01

443

Greenhouse gas emissions from the international maritime transport of New Zealand's imports and exports  

International Nuclear Information System (INIS)

Greenhouse gas emissions from international maritime transport are exempt from liabilities under the Kyoto Protocol. Research into quantifying these emissions is ongoing, and influences policy proposals to reduce emissions. This paper presents a cargo-based analysis of fuel consumption and greenhouse gas emissions from New Zealand's international maritime transport of goods. Maritime transport moves 99.5% (by mass) of New Zealand's internationally traded products. It is estimated that 73% of visiting vessels' activity can be directly attributed to the movement of goods in and out of New Zealand. A cargo-based methodology was used to estimate that the international maritime transport of New Zealand's imports and exports consumed 2.5 million tonnes (Mt; 2.6 billion litres) of fuel during the year 2007, which generated 7.7 Mt of carbon dioxide (CO_2) emissions. Double-counting of emissions would occur if a similar method was applied to all New Zealand's trading ...

2011-03-01

444

Fundamental Elements of Geologic C02 Sequestration in Saline Aquifers  

Energy Technology Data Exchange (ETDEWEB)

Geologic sequestration represents a promising strategy for isolating CO{sub 2} waste streams from the atmosphere. Successful implementation of this approach hinges on our ability to predict the relative effectiveness of subsurface CO{sub 2} migration and sequestration as a function of key target-formation and cap-rock properties, which will enable us to identify optimal sites and evaluate their long-term isolation performance. Quantifying this functional relationship requires a modeling capability that explicitly couples multiphase flow and kinetically controlled geochemical processes. We have developed a unique computational package that meets these criteria, and used it to model CO{sub 2} injection at Statoil's North-Sea Sleipner facility, the world's first saline-aquifer storage site. The package integrates a state-of-the-art reactive transport simulator (NUFT) with supporting geochemical software and databases (SUPCRT92). In our Sleipner ...

2001-11-19

445

A clinical assessment of the relationship between bone scintigraphy and serum biochemical markers in hemodialysis patients  

International Nuclear Information System (INIS)

Renal osteodystrophy is a metabolic bone disease and a common complication of end-stage chronic renal failure and maintenance dialysis treatment. In this study, we examined the correlation between quantifying bone scintigraphy and serum biochemical markers in hemodialysis patients. Bone scintigraphy with technetium-99m-hydroxy-methylene-diphosphonate ("9"9"mTc-HMDP) was performed on 28 patients on maintenance hemodialysis. Bone scintigraphy was performed using a standard protocol and was quantified by setting regions of interest (ROIs) over selected regions. The bone-to-soft-tissue ratio (B/ST ratio) at each region was calculated in all patients. The B/ST ratios were then compared with serum biochemical markers. The B/ST ratio for the skull correlated well with serum bone-specific alkaline phosphatase (BAP) (r=0.735, p<0.001), serum deoxypyridinoline (DPD) (r=0.806, p<0.001) and intact parathyroid hormone (intact PTH) (r=0.701, ...

2004-09-01

446

USE OF A CONTROLLED CHLORINE DIOXIDE (CLO2) RELEASE SYSTEM IN COMBINATION WITH MODIFIED ATMOSPHERE PACKAGING (MAP) TO CONTROL THE GROWTH OF PATHOGENS  

British Library Electronic Table of Contents (United Kingdom)

Abstract Salmonella Typhimurium and Listeria monocytogenes are major bacterial pathogens associated with poultry products. A controlled released ClO2 sachet applied with modified atmosphere packaging (MAP) was evaluated for its ability to control the growth of S. Typhimurium and L. monocytogenes on raw chicken breast during refrigerated storage. The fresh chicken samples were inoculated with one or the other of the pathogens at 104-cfu/g, and the packages (with and without ClO2 sachet) were flushed with ambient air or 30% CO2/70% N2 before sealing, and then stored at 4C for up to 21 days. The maximum reduction in MAP plus ClO2 (compared with MAP alone) was 0.68-log-cfu/g for S. Typhimurium and 1.87-log-cfu/g for L. monocytogenes. Color and pH changes of the chicken breast were observed at ...

2011-01-01

447

Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges  

Energy Technology Data Exchange (ETDEWEB)

Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced ...

1995-12-31

448

Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges  

International Nuclear Information System (INIS)

Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The observed shift with time in the molecular weight distribution of hydrocarbon material was more pronounced ...

1995-04-24

449

Test of electron beam technology on Savannah River Laboratory low-activity aqueous waste for destruction of benzene, benzene derivatives, and bacteria  

Energy Technology Data Exchange (ETDEWEB)

High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam ...

1993-08-01

450

Shellfish depuration by gamma irradiation: Final report for the period October 1, 1985-September 30, 1986  

International Nuclear Information System (INIS)

Irradiation of live bivalve molluscs is a promising new technique to reduce the public health threats of viral and bacterial pathogens in the consumption of raw shellfish. In studies conducted within the past year, live hardshelled clams and oysters were innoculated with Simian Rotavirus SA-11, Poliovirus I, and Hepatitis-A virus and treated with gamma ray ionizing radiation from University of Lowell/DOE 800,000 Curie "6"0Co source over a dose range of 0.5--10 kiloGray (50--1000 kilorad) to determine the effectiveness of the process in eliminating viral activity and thus easing the potential viral health threats associated with uncooked bivalves. Two viral strains, SA-11 and Poliovirus I, were employed as models to perfect laboratory technique and to estimate the most appropriate range of dose exposures necessary for optimal inactivation of the infectious pathogen, Hepatitis A. Post-irradiation survivorship of the oysters and quahogs was assessed over a range of ...

451

Radioactive-electrophoretic assay of adenosine 5'-triphosphate sulfurylase activity in crude extracts with sulfate or selenate as a substrate  

Energy Technology Data Exchange (ETDEWEB)

An assay method for ATP sulfurylase is presented which employs Na/sub 2/(35)SO/sub 4/ as a substrate and measures the production of labeled adenosine 5'-phosphosulfate and 3'-phosphoadenosine 5'-phosphosulfate by low-voltage, hanging paper strip electrophoresis. The method is applicable to crude bacterial or mammalian extracts and accurately measures picomole amounts of product(s). Na/sub 2/(/sup 75/)SeO/sub 4/ can also be employed as a substrate, if the unstable radioactive product, adenosine 5'-phosphoselenate, is converted to elemental /sup 75/Se degrees by inclusion of reduced glutathione in the reaction mixture. The same paper strip electrophoretic technique can then be used to separate /sup 75/Se degrees from the radiolabeled substrate. The method also has utility for measuring any direct reduction by crude microbial extracts of radioactive selenate to selenite, independent of ATP sulfurylase.

1989-02-01

452

Predominant and common cause of urinary tract infection(s) in sukkur city  

International Nuclear Information System (INIS)

To examine and evaluate the predominant and common etiologic agent(s) of urinary tract infection (UTI) in Sukkur city and to determine their current antibiotic susceptibility/resistance trends. Nine hundred sixty six patients out of 1430 abnormal urine reports (showing significant abnormalities such as protein, pus, red cells) were asked to give second sample. The urine samples were examined by both urine test strip (Combur 10 Test, Roche) and microscopically (wet preparation) followed by culture and sensitivity. The culture sensitivity was done on urine samples of which bacterial numbers were estimated as more than 105CFU. The study was conducted at Safeway Diagnostic and Research Laboratory Sukkur and the Department of Microbiology, Shah Abdul Latif University Khairpur, Sindh from March 2001 to March 2003. Eight hundred fifty-two (88.2%) showed Escherichia spp followed by Klebsiella spp (6.9%) and proteus spp (4.9%). These showed 95%, 90%, 90% sensitivity to ...

2001-03-01

453

Poncirin promotes osteoblast differentiation but inhibits adipocyte differentiation in mesenchymal stem cells.  

Science.gov (United States)

Poncirin, flavanone glycoside, isolated from the fruit of Poncirus trifoliata, has anti-bacterial and anti-inflammatory activities. In this study, the effects of poncirin on the differentiation of mesenchymal stem cells were investigated. The C3H10T1/2 mesenchymal stem cells and primary bone marrow mesenchymal stem cells were studied. In the C3H10T1/2 cells, poncirin prevented adipocyte differentiation, as demonstrated by inhibition of cytoplasm lipid droplet accumulation and peroxisome proliferator-activating receptor-? (PPAR-?) and CCAAT-enhancer-binding protein-? (C/EBP-?) mRNA expression. By contrast, poncirin enhanced the expression of the key osteogenic transcription factors, runt-related transcription factor 2 (Runx2) and transcriptional coactivator with PDZ-binding motif (TAZ). Poncirin also enhanced expression of the osteogenic marker genes including alkaline phosphatase (ALP) and osteocalcin (OC). Poncirin increased mineral nodule formation in primary ...

2011-05-01

454

Methanogens and sulfate-reducing bacteria in oil sands fine tailings waste.  

Science.gov (United States)

In the past decade, the large tailings pond (Mildred Lake Settling Basin) on the Syncrude Canada Ltd. lease near Fort McMurray, Alta., has gone methanogenic. Currently, about 60%-80% of the flux of gas across the surface of the tailings pond is methane. As well as adding to greenhouse gas emissions, the production of methane in the fine tailings zone of this and other settling basins may affect the performance of these settling basins and impact reclamation options. Enumeration studies found methanogens (10(5)-10(6) MPN/g) within the fine tailings zone of various oil sands waste settling basins. SRB were also present (10(4)-10(5) MPN/g) with elevated numbers when sulfate was available. The methanogenic population was robust, and sample storage up to 9 months at 4 degrees C did not cause the MPN values to change. Nor was the ability of the consortium to produce methane delayed or less efficient after storage. Under laboratory conditions, fine tailings samples released 0.10-0.25 mL CH4 ...

2000-10-01

455

Intracellular monitoring of superoxide dismutase expression in an Escherichia coli fed-batch cultivation using on-line disruption with at-line surface plasmon resonance detection.  

Science.gov (United States)

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 ...

2005-07-01

456

Identification of sucrose binding, membrane proteins using a photolyzable sucrose analog. [P. saccharophila  

Energy Technology Data Exchange (ETDEWEB)

The sucrose derivative 6'-deoxy-6'-(2-hydroxy-4-azido)benzamidosucrose (6'-HABS) was prepared from sucrose (via 6'-deoxy-6'-aminosucrose) and 4-amino-salicylic acid. 6'-HABS is a competitive inhibitor of sucrose influx into protoplasts from developing soybean cotyledons and of sucrose binding to membranes from the bacteria P. saccharophila. The Ki for inhibition in the soybean protoplasts was 75..mu..M. 6'-Deoxy-6'-(2-hydroxy-3-/sup 125/Iodo-4-azido)benzamidosucrose was prepared by lactoperoxidase iodination of 6'-HABS. Upon photolysis in the presence of membranes from P saccharophila, label from the photoprobe is incorporated into a sucrose inducible polypeptide of mass 84 KD in SDS-PAGE. The polypeptide is protected from labeling by the inclusion of sucrose in the photolysis mixture. Photolysis conditions which lead to specific labeling of the sucrose protectable polypeptide in ...

1986-04-01

457

Gene discovery in the Acanthamoeba castellanii genome  

Energy Technology Data Exchange (ETDEWEB)

Acanthamoeba castellanii is a free-living amoeba found in soil, freshwater, and marine environments and an important predator of bacteria. Acanthamoeba castellanii is also an opportunistic pathogen of clinical interest, responsible for several distinct diseases in humans. In order to provide a genomic platform for the study of this ubiquitous and important protist, we generated a sequence survey of approximately 0.5 x coverage of the genome. The data predict that A. castellanii exhibits a greater biosynthetic capacity than the free-living Dictyostelium discoideum and the parasite Entamoeba histolytica, providing an explanation for the ability of A. castellanii to inhabit adversity of environments. Alginate lyase may provide access to bacteria within biofilms by breaking down the biofilm matrix, and polyhydroxybutyrate depolymerase may facilitate utilization of the bacterial storage compound polyhydroxybutyrate as a food source. Enzymes for the synthesis and ...

2005-08-01

458

Evolution of a molecular switch: universal bacterial GTPases regulate ribosome function.  

Science.gov (United States)

The GTPases comprise a protein superfamily of highly conserved molecular switches adapted to many diverse functions. These proteins are found in all domains of life and often perform essential roles in fundamental cellular processes. Analysis of data from genome sequencing projects demonstrates that bacteria possess a core of 11 universally conserved GTPases (elongation factor G and Tu, initiation factor 2, LepA, Era, Obg, ThdF/TrmE, Ffh, FtsY, EngA and YchF). Investigations aimed at understanding the function of GTPases indicate that a second conserved feature of these proteins is that they elicit their function through interaction with RNA and/or ribosomes. An emerging concept suggests that the 11 universal GTPases are either necessary for ribosome function or transmitting information from the ribosome to downstream targets for the purpose of generating specific cellular responses. Furthermore, it is suggested that progenitor GTPases were early regulators of RNA function and may have ...

2001-07-01

459

Evaluation of chicken manure, kenaf, and phanerochaete chrysosporium (white rot fungus) as enhancers of polychlorinated biphenyl biodegradation  

Energy Technology Data Exchange (ETDEWEB)

In this 150-day study, chicken manure, kenaf, and white rot fungus were added to soil microcosms in an attempt to enhance the degradation of polychlorinated biphenyls. The soil was contaminated with commercial PCB mixtures. Dishes were ammended with 5% dry weight chicken manure, 1% dry weight kenaf, and 1% dry weight kenaf plus Phanerochaete chrysosporium inoculant. PCB concentrations were determined at 30 day intervals by soxhlet extraction and gas chromatography analyses. Preliminary results of microbial populations and PCB degradation are presented. At 90 days, the microcosms amended with chicken manure had significantly higher populations of bacteria, fungi, and actinomycetes. However, at 120 days, these soils underwent great reductions in actinomycete and bacterial populations. Through 60 days, the concentration of the PCBs Aroclor 1242 and 1248 had its greatest reduction in the kenaf amended soils. The concentration of Aroclor 1260 either increased or stayed ...

1995-12-31

460

Equilibrium and thermodynamic parameters of single and binary mixture biosorption of lead (II) and copper (II) ions onto Pseudomonas putida: Effect of temperature  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of lead (II) and copper (II) ions, single component and binary systems, by dried P. putida was investigated in a batch system. The effects of initial pH, temperature, initial single and binary mixture concentrations on the biosorption kinetics and equilibrium uptake of each component, both single and binary mixtures were investigated. The bacterial biomass exhibited the highest single and binary lead (II) and copper (II) ions uptake capacity at 25 and 30 deg. C, respectively, the initial pH value of 5.5 and at the initial metal ions concentration of 100 mg dm{sup -3}. The Freundlich and Langmuir adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated at different temperatures. Adsorption data were well described by the Langmuir model, although they could be modeled by the Freundlich equation. The thermodynamics constants of the adsorption process: {delta}H{sup o}, {delta}S{sup ...

2006-07-31

461

Detection of abnormalities in febrile AIDS patients with In-111-labeled leukocyte and Ga-67 scintigraphy  

International Nuclear Information System (INIS)

Thirty-six patients with acquired immunodeficiency syndrome (AIDS), who were febrile but without localizing signs, underwent indium-111 leukocyte scintigraphy 24 hours after injection of labeled white blood cells (WBCs) and were restudied 48 hours after injection of gallium-67 citrate. Fifty-six abnormalities were identified as possible sources of the fever; 27 were confirmed with biopsy. Of these 27, 15 were identified only on In-111 WBC scans (including colitis, sinusitis, and focal bacterial pneumonia); six, only on Ga-67 scans (predominantly Pneumocystis carinii pneumonia and lymphadenopathy); and six, on both studies (predominantly pulmonary lesions). In-111 WBC scanning revealed 21 of 27 abnormalities (78%) and gallium scanning, 12 of 27 (44%). If only one scintigraphic study has been performed, particularly with Ga-67, a significant number of lesions would not have been detected. The authors believe radionuclide evaluation of the febrile AIDS patient without ...

462

Comparison of maintenance energy expenditures and growth yields among several rumen bacteria grown on continuous culture.  

Science.gov (United States)

Maintenance energy expenditures were mesured for five rumen bacteria, Selenomonas ruminantium, Butyrivibrio fibrisolvens, Bacteroides ruminicola, Megasphaera elsdenii, and Streptococcus bovis, by using a complex medium with glucose as the carbon source. Large differences (as high as 8.5-fold) in maintenance energy expenditures were seen among these bacteria. The suggestion is made that maintenance requirements could be a significant determinant of bacterial competition in the rumen. Theoretical maximum growth yields, calculated from double reciprocal plots of yield versus dilution rate, were compared to theoretical Y(ATP) values in order to estimate minimum molar adenosine 5'-triphosphate yields from glucose for each bacterium. Results showed that relative yield among the bacteria was growth rate dependent. At high dilution rates, both S. ruminantium and S. bovis produced lactate as their principal fermentation product. At lower dilution rates very little lactate ...

1979-03-01

463

Chemical and biological monitoring of MIOR on the pilot area of Vyngapour oil field, West Sibera, Russia  

Energy Technology Data Exchange (ETDEWEB)

The pilot area of the Vyngapour oil field allotted for MIOR tests contains three injection and three producing wells. These wells were treated in summer 1993 and 1994. Before, during, and after MIOR treatments on the pilot area the chemical compounds of injected and formation waters were studied, as well as the amount and species of microorganisms entering the stratum with the injected water and indigenous bacteria presented in bottomhole zones of the wells. The results of monitoring showed that the bottomhole zone of the injection well already had biocenosis of heterotrophic, hydrocarbon-oxidizing, methanogenic, and sulfate-reducing bacteria, which were besides permanently introduced into the reservoir during the usual waterflooding. The nutritious composition activated vital functions of all bacterial species presented in the bottomhole zone of the injection well. The formation waters from producing wells showed the increase of the content of nitrate, sulfate, ...

1995-12-31

464

Biological control of take-all in wheat by endophytic Bacillus subtilis E1R-j and potential mode of action  

British Library Electronic Table of Contents (United Kingdom)

The bacterial strain E1R-j, isolated as an endophyte from wheat roots, exhibited high antifungal activity to Gaeumannomyces graminis var. tritici (Ggt). Strain E1R-j was identified as Bacillus subtilis based on morphological, physiological and biochemical methods as well as on 16S rDNA analysis. This strain inhibited mycelium growth in vitro of numerous plant pathogenic fungi, especially of Ggt, Coniothyrium diplodiella, Phomopsis sp. and Sclerotinia sclerotiorum. In greenhouse experiments, soil drenches with cell densities of 106, 109 and 1012CFU ml-1 E1R-j reduced significantly take-all disease, caused by Ggt, in wheat seedling by 62.6%, 68.6% and 70.7%, respectively, compared to the inoculated control, 4weeks after sowing. Growth parameters such as lengths and fresh weights of roots and...

2009-01-01

465

Bacterial competition between a bacteriocin-producing and a bacteriocin-negative strain of Streptococcus bovis in batch and continuous culture:  

British Library Electronic Table of Contents (United Kingdom)

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...

2006-01-01

466

Artesunate in combination with oxacillin protect sepsis model mice challenged with lethal live methicillin-resistant Staphylococcus aureus (MRSA) via its inhibition on proinflammatory cytokines release and enhancement on antibacterial activity of oxacillin  

British Library Electronic Table of Contents (United Kingdom)

Sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) has worse outcome because of multiresistance to a large group of antibiotics, which may lead to death from septic shock. In the present study, we firstly found that artesunate in combination with oxacillin was capable of protecting mice challenged with live MRSA WHO-2 (WHO-2) and the protection was related to the reduced TNF-a and IL-6 levels and decreased bacterial load. Based on above results, artesunate was further investigated from two aspects in vitro, anti-inflammation effect and antibacterial enhancement effect on antibiotics. Artesunate not only inhibited TNF-a and IL-6 release but also inhibited mRNA and protein expressions of TLR2 and Nod2, two important receptors, in murine peritoneal macrophages stimulated wit...

2011-01-01

467

Anaerobic degradation of DCM diffusing through clay  

Energy Technology Data Exchange (ETDEWEB)

Two series of diffusion tests were performed to examine the degradation of dichloromethane (DCM) as it diffuses through clay. The first series showed the use of a synthetic leachate with no significant initial bacterial population diffusing through a plug of intact clay; there was an induction period of 95--135 d, during which diffusion was as expected in the absence of degradation, followed by a second stage, where degradation occurred with an apparent half-life of less than 55 d at a temperature of 24 C. The second series of tests examined the diffusion of an actual leachate from the Keele Valley Landfill (KVL) (which provided both nutrients and a source of bacteria), through a compacted clay. In these tests, the induction period was reduced to 40--60 d, after which the apparent half-life was 20 d or less at 27 C. The diffusion coefficient for DCM was approximately 8 {times} 10{sup {minus}10} m{sup 2}/s, with partitioning coefficient K{sub d} = 1.5 cm{sup 3}/g. ...

1997-12-01

468

Adaptation of oral streptococci to low pH.  

Science.gov (United States)

The strategies employed by oral streptococci to resist the inimical influences of acidification reflect the diverse and dynamic niches of the human mouth. All of the oral streptococci are capable of rapid degradation of sugar to acidic end-products. As a result, the pH value of their immediate environment can plummet to levels where glycolysis and growth cease. At this point, the approaches for survival in acid separate the organisms. Streptococcus mutans, for example, relies on its F-ATPase, to protect itself from acidification by pumping protons out of the cells. S. salivarius responds by degrading urea to ammonia and S. sanguis produces ammonia by arginolysis. The mechanisms by which these organisms regulate their particular escape route are now being explored experimentally. The picture that emerges is that the acid-adaptive regulatory mechanisms of the oral streptococci differ markedly from those employed by Gram-negative bacteria. What remains to be elucidated are the breadth of ...

2000-01-01

469

Activity of Citrus Essential Oils against-Escherichia coli-O157:H7 and-Salmonella-spp. and Effects on Beef Subprimal Cuts under Refrigeration  

British Library Electronic Table of Contents (United Kingdom)

Abstract:- Escherichia coli-O157:H7 and-Salmonella-spp. are bacterial pathogens often associated with beef, and cause many cases of foodborne illness each year in the United States. During beef slaughter and processing, these bacteria may spread from the hide or intestines to the carcass. The objective of this research was to investigate the use of naturally occurring compounds citrus essential oils (CEOs) extracted from orange peel to reduce or eliminate these pathogens at the chilling stage of processing, or during fabrication. Brisket flats (used to simulate beef subprimals) were spot inoculated with approximately 6 log of surrogate generic-E. coli-cocktail (previously shown to be identical in growth and survival parameters to-E. coli-O157:H7 and-Salmonella-spp.). Following drying, CEOs...

2011-01-01

470

A biogenic approach to the treatment of uranium mill effluents  

International Nuclear Information System (INIS)

A biogenic method for the treatment of uranium mill effluents containing toxic amounts of Mn"2 and "2"2"6Ra is described. The acidic tailings from the uranium mills are generally neutralised with lime and the overflow waters from tailing ponds at the discharge point, consisting of Mn"2"+ (>10 mg l"-"1) and "2"2"6Ra (> 3.0 pCi l"-"1), need further treatment before disposing off to the public utility. Arthrobacter sp. has been used for precipitating Mn"2"+ as hydrous oxide of manganes (MnO_2#centre dot#nH_2O) and along with "2"2"6Ra also gets precipitated. The effluent after bacterial treatment consisted of Mn"2"+ and "2"2"6Ra within the range of allowed concentrations as per the I.C.R.P. (International Committee of Radiological Protection) and MPC (maximum permissible concentration) standards (Mn"2"+ 95% of "2"2"6Ra could be precipitated using this method. (author). 11 refs.; 4 figs.; 4 tabs.

471

Visualization by PIV of dynamic stall on a vertical axis wind turbine  

Energy Technology Data Exchange (ETDEWEB)

The aerodynamic behavior of a vertical axis wind turbine (VAWT) is analyzed by means of 2D particle image velocimetry (PIV), focusing on the development of dynamic stall at different tip speed ratios. The VAWT has an unsteady aerodynamic behavior due to the variation with the azimuth angle {theta} of the blade's sections' angle of attack, perceived velocity and Reynolds number. The phenomenon of dynamic stall is then an inherent effect of the operation of a VAWT at low tip speed ratios, impacting both loads and power. The present work is driven by the need to understand this phenomenon, by visualizing and quantifying it, and to create a database for model validation. The experimental method uses PIV to visualize the development of the flow over the suction side of the airfoil for two different reference Reynolds numbers and three tip speed ratios in the operational regime of a small urban wind turbine. The field-of-view of the experiment covers ...

2009-01-15

472

The state of energy storage in electric utility systems and its effect on renewable energy resources  

Energy Technology Data Exchange (ETDEWEB)

This report describes the state of the art of electric energy storage technologies and discusses how adding intermittent renewable energy technologies (IRETs) to a utility network affects the benefits from storage dispatch. Load leveling was the mode of storage dispatch examined in the study. However, the report recommended that other modes be examined in the future for kilowatt and kilowatt-hour optimization of storage. The motivation to install storage with IRET generation can arise from two considerations: reliability and enhancement of the value of energy. Because adding storage increases cost, reliability-related storage is attractive only if the accruing benefits exceed the cost of storage installation. The study revealed that the operation of storage should not be guided by the output of the IRET but rather by system marginal costs. Consequently, in planning studies to quantify benefits, storage should not be considered as an entity belonging to the system ...

1994-08-01

473

The effect of boron implant energy on transient enhanced diffusion in silicon  

Energy Technology Data Exchange (ETDEWEB)

Transient enhanced diffusion (TED) of boron in silica after low energy boron implantation and annealing was investigated using boron-doping superlattices (DSLs) grown by low temperature molecular beam epitaxy. Boron ions were implanted at 5, 10, 20, and 40 keV at a constant dose of 2{times}10{sup 14}/cm{sup 2}. Subsequent annealing was performed at 750{degree}C for times of 3 min, 15 min, and 2 h in a nitrogen ambient. The broadening of the boron spikes was measured by secondary ion mass spectroscopy and simulated. Boron diffusivity enhancement was quantified as a function of implant energy. Transmission electron microscopy results show that {l_angle}311{r_angle} defects are only seen for implant energies {ge}10 keV at this dose and that the density increases with energy. DSL studies indicate the point defect concentration in the background decays much slower when {l_angle}311{r_angle} defects are present. These results imply there are at least two sources of TED ...

1997-02-01

474

The conversion model: A strategic market segmentation system based on customer commitment and potential to change  

Energy Technology Data Exchange (ETDEWEB)

Deregulation of utilities will require providers of electric power to put the issue of competition at the top of their strategic planning agenda. The companies that will flourish in this new competitive environment are those that have strongly committed customers and potential to grow. {open_quotes}Commitment{close_quotes} is the complex psychological bond between a customer and a brand (or choice); it is critical to measure because it is the foundation of loyalty and brand equity. The Conversion Model is an established, validated strategic research tool that measures customer commitment and potential to change. It was designed to help marketers devise strategies to strengthen the commitment of current customers and to acquire new customers. The Model helps companies protect and grow their businesss by first quantifying the commitment of current customers and the potential to convert competitors` customers. Further, the Model provides managers with actionable ...

1994-11-01

475

Studies of osteoporosis in Singapore using isotope-related techniques  

International Nuclear Information System (INIS)

The main objectives of this study was to determine the bone density for the purposes of i) determining the age of peak bone mass in each study group and ii) quantifying the differences in bone density as functions of age and sex. The results of estimating the age dependence of mineral density for the femoral neck, spine and total body of healthy women and men using DEXA are given. The age changes in concentrations of major minerals and electrolytes found for compact and trabecular bones of healthy male femoral neck with regard for the wet and dry tissue calculations are represented. Information about femoral neck water content depending on the age of healthy men is tabulated. The number of performed observations and analyses is evidently insufficient to make any final decision, however some preliminary conclusions can be drawn. In accordance with DEXA results, BMD maximum for the femoral neck, spine and total body of healthy women is found for 31-35 age period ...

1996-10-07

476

Scatter measurements for optical cone-beam computed tomography  

Energy Technology Data Exchange (ETDEWEB)

Both x-ray and optical cone-beam CT (CBCT) scanners are limited by scattered photons that contaminate the primary images. Transparent radiochromic gels and plastics are anticipated to produce less scattering than polymerization gels and hence result in reconstructed dose distributions with greater contrast and dynamic range. Four methods of scatter measurement were investigated to quantify scatter fractions using an in-house optical CBCT scanner. The methods consisted of generating either 'coin' shadows or primary beamlets in transmission images. The four methods generated similar results of 10% scatter fractions in gel transmission images for this particular scanner configuration with both leuco crystal violet and carbon black micelle gels. The scatter contributions were distributed as 5% from micelle gel, 2% from Teflon wall, 2% from refractive index matching liquid and 1% other sources. Applying a uniform background subtraction of 2% of open ...

2009-05-01

477

Response of a Spent Fuel Transportation Cask to a Tunnel Fire Event  

Energy Technology Data Exchange (ETDEWEB)

The staff of the Spent Fuel Project Office at the U.S. Nuclear Regulatory Commission undertook the investigation and thermal analysis of the Baltimore tunnel fire event. This event occurred in the Howard Street tunnel, in Baltimore, Maryland, on July 18, 2001. The staff was tasked with assessing the consequences of this event on the transportation of spent nuclear fuel. This paper describes the staff's coordination with the following government and laboratory organizations: the National Transportation Safety Board (NTSB), to determine the details of the train derailment and fire; the National Institute of Standards and Technology (NIST), to quantify the thermal conditions within the tunnel; the Center for Nuclear Waste Regulatory Analysis (CNWRA), to validate the NIST evaluations, and the Pacific Northwest National Laboratory (PNNL), to assist in the thermal analysis. The results of the staff's review and analysis efforts are also discussed. The ...

2003-02-25

478

Requirements for modeling and simulation of space RSTA assets  

Science.gov (United States)

The Department of Defense (DoD) has long depended on military support functions enabled by space reconnaissance, surveillance, and target acquisition (RSTA) assets. Future generation satellite capabilities will further push technologies in space - if the right technologies are deployed in the right numbers and with the right payloads. Modeling and simulation play major parts in developing and deploying such assets: 1) system and operational requirements determination, and 2) assessment of military utility of such assets. Each area is critical in a system"s life cycle. Requirements determination cuts across the issues of doctrine, organizations, training, materiel, leader development, personnel, and facilities (DOTMLPF). Military utility assessments are necessary to explore and quantify the military worth/benefit of space RSTA assets to operational commanders. Each of these areas requires relevant modeling/simulation tools which span the engineering to system to ...

2004-09-01

479

Reduction of transient diffusion from 1{endash}5 keV Si{sup +} ion implantation due to surface annihilation of interstitials  

Energy Technology Data Exchange (ETDEWEB)

The reduction of transient enhanced diffusion (TED) with reduced implantation energy has been investigated and quantified. A fixed dose of 1{times}10{sup 14} cm{sup {minus}2} Si{sup +} was implanted at energies ranging from 0.5 to 20 keV into boron doping superlattices and enhanced diffusion of the buried boron marker layers was measured for anneals at 810, 950, and 1050{degree}C. A linearly decreasing dependence of diffusivity enhancement on decreasing Si{sup +} ion range is observed at all temperatures, extrapolating to {approximately}1 for 0 keV. This is consistent with our expectation that at zero implantation energy there would be no excess interstitials from the implantation and hence no TED. Monte Carlo modeling and continuum simulations are used to fit the experimental data. The results are consistent with a surface recombination length for interstitials of {lt}10 nm. The data presented here demonstrate that in the range of annealing temperatures of ...

1997-11-01

480

Reduction of transient diffusion from 1 endash 5 keV Si"+ ion implantation due to surface annihilation of interstitials  

International Nuclear Information System (INIS)

The reduction of transient enhanced diffusion (TED) with reduced implantation energy has been investigated and quantified. A fixed dose of 1x10"1"4 cm"-"2 Si"+ was implanted at energies ranging from 0.5 to 20 keV into boron doping superlattices and enhanced diffusion of the buried boron marker layers was measured for anneals at 810, 950, and 1050 degree C. A linearly decreasing dependence of diffusivity enhancement on decreasing Si"+ ion range is observed at all temperatures, extrapolating to #approx#1 for 0 keV. This is consistent with our expectation that at zero implantation energy there would be no excess interstitials from the implantation and hence no TED. Monte Carlo modeling and continuum simulations are used to fit the experimental data. The results are consistent with a surface recombination length for interstitials of <10 nm. The data presented here demonstrate that in the range of annealing temperatures of interest for p-n junction formation, TED is ...

481

Quantifying bid-ask spreads in the Chinese stock market using limit-order book data: Intraday pattern, probability distribution, long memory, and multifractal nature  

CERN Document Server

The statistical properties of the bid-ask spread of a frequently traded Chinese stock listed on the Shenzhen Stock Exchange are investigated using the limit-order book data. Three different definitions of spread are considered based on the time right before transactions, the time whenever the highest buying price or the lowest selling price changes, and a fixed time interval. The results are qualitatively similar no matter linear prices or logarithmic prices are used. The average spread exhibits evident intraday patterns consisting of a big L-shape in the morning and a small L-shape in the afternoon. The distributions of the spread with different definitions decay as power laws. The tail exponents of spreads at transaction level are well within the interval $(2,3)$ and that of average spreads are well in line with the inverse cubic law for different time intervals. Based on the detrended fluctuation analysis, we find evidence of long memory in the bid-ask spread time series for all ...

2006-01-01

482

Platelet thrombosis in cardiac-valve prostheses  

International Nuclear Information System (INIS)

The contribution of platelets and clotting factors in thrombosis on cardiovascular prostheses had been quantified with several tracers. Thrombus formation in vivo could be measured semiquantitatively in animal models and patients with indium-111, Technetium-99m labeled platelets, iodine-123, iodine-131 labeled fibrinogen, and In-111 and Tc-99m labeled antibody to the fibrinogen-receptor on the platelet- membrane, or fibrin. The early studies demonstrated that certain platelet-inhibitors, e.g. sulfinpyrazone, aspirin or aspirin- persantine increased platelet survival time with mechanical valves implanted in the baboon model and patients. Thrombus localization by imaging is possible for large thrombus on thrombogenic surface of prosthesis in the acute phase. The majority of thrombus was found in the sewing ring (Dacron) in the acute phase in both the mechanical and tissue valves. The amount of retained thrombus in both mechanical and tissue valves in our one-day ...

1989-06-08

483

On the application of Allan variance method for Ring Laser Gyro performance characterization  

Energy Technology Data Exchange (ETDEWEB)

This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and recursive implementation approaches, validates ...

1993-10-15

484

Musculoskeletal injuries in an Army airborne population.  

Science.gov (United States)

To maintain operational readiness, military personnel engage in vigorous physical and training activities that carry risk for injury. A 1-year prospective cohort study, starting April 1996, was conducted at Fort Bragg, North Carolina among 1,965 members of the 82nd Airborne Division to quantify musculoskeletal injuries. Information collected included type of injury, site, circumstances, and resultant limited duty days. These soldiers suffered 508 overuse injuries (including 38 stress fractures), 1,415 traumatic injuries (including 100 fractures), and 101 unclassified injuries. Injury rates were 6.8% per soldier per month for traumatic injury and 2.4% for overuse injury (totaling 1.2 injuries per soldier per year). Injuries resulted in 22,041 limited duty days, averaging 11 days per injury and 13 days per soldier (4.5% of total workdays). Fractures and stress fractures/reactions produced the most days lost per case. Most of these injuries resulted from ...

2002-12-01

485

Monitoring the Effect of Longwall Mining on Agricultural Environments - Interim Report  

Energy Technology Data Exchange (ETDEWEB)

The project was designed to quantify the impacts of longwall mine subsidence (LWMS) on the production and quality of agricultural vegetated environments. This project utilised a variety of traditional ground based sampling techniques including biomass harvests and estimates, leaf area index (LAI), pasture height, species composition and soil sampling along with proximal sensor data capture using a Crop Circle{trademark} and an EM38. Satellite imagery was collected using the Quickbird satellite and the high resolution imagery was used to monitor large areas of LWMS affected areas and adjacent un-mined land. Two landscapes were investigated using a whole of mine site technique including remote sensing, ground survey and traditional agricultural monitoring methods. The landscapes were at the Kestrel site in Emerald, QLD including a forage sorghum and an improved pasture and at Beltana in the Hunter Valley, NSW including an irrigated lucerne pasture and an unimproved ...

2009-06-15

486

Interaction of climate and land use in future terrestrial carbon storage and release  

Energy Technology Data Exchange (ETDEWEB)

The processes controlling total carbon (C) storage and release from the terrestrial biosphere are still poorly quantified. We conclude from analysis of paleodata and climatebiome model output that terrestrial C exchanges since the last glacial maximum (LGM) were dominated by slow processes of C sequestration in soils, possibly modified by C starvation and reduced water use efficiency of trees during the LGM. In contrast, future C cycling will be dominated by human activities, not only from increasing C release with burning of fossil fuels, and but also from indirect effects which increase C storage in the terrestrial biosphere and decrease C storage in the biosphere. Comparison of the positive and negative C flux processes involved suggests that if the C sequestration processes are important, they likely will be so during the next few decades, gradually being counteracted by the C release processes. (Copyright (c) l993 Kluwer Academic Publishers.)

1993-01-01

487

Impact of kerogen heterogeneity on sorption of organic pollutants. 2. Sorption equilibria  

Energy Technology Data Exchange (ETDEWEB)

Phenanthrene and naphthalene sorption isotherms were measured for three different series of kerogen materials using completely mixed batch reactors. Sorption isotherms were nonlinear for each sorbate-sorbent system, and the Freundlich isotherm equation fit the sorption data well. The Freundlich isotherm linearity parameter n ranged from 0.192 to 0.729 for phenanthrene and from 0.389 to 0.731 for naphthalene. The n values correlated linearly with rigidity and aromaticity of the kerogen matrix, but the single-point, organic carbon-normalized distribution coefficients varied dramatically among the tested sorbents. A dual-mode sorption equation consisting of a linear partitioning domain and a Langmuir adsorption domain adequately quantified the overall sorption equilibrium for each sorbent-sorbate system. Both models fit the data well, with r{sup 2} values of 0.965 to 0.996 for the Freundlich model and 0.963 to 0.997 for the dual-mode model for the phenanthrene ...

2009-08-15

488

Immediate responses of forests to understorey fires during the 2010 Amazonian drought  

Environmental Research Database

ObjectivesThe overall aim of this proposal is to make use of the unique opportunity afforded by the 2010 Amazonian Drought in order to quantify the basin-wide impacts of an intense forest fire season on above and below-ground carbon stocks and ecophysiological changes in forest functioning. The specific objectives relating to our research questions are: O1. Assess the causes and spatial extent of the 2010 drought in terms of basin-wide rainfall anomalies and water deficits and their relationship wi [continued...]DescriptionDespite an 82% decline in deforestation rates in Amazonia, fires are still on the rise. 2010 has been a year of severe drought and fire in Amazonia. Over the last months (July and August) the number of fire counts has reached 80% of the 2005 values, which was characterized as the drought of the century. Through the beginning of September, fire outbreaks have intensified in southwest Amazonia, including Brazil, Peru and Bolivia. This drought has ...

2011-01-30

489

Geothermal Heat Pump research and development studies at Sandia National Laboratories  

Energy Technology Data Exchange (ETDEWEB)

The Geothermal Heat Pump (GHP) concept was originally developed in the 1940`s. Recently, because of increasing energy costs, utility interest, and the development of simple and durable ground source heat exchangers, GHP`s have gained international attention as a proven means of energy conservation and electrical peak power demand reduction. GHP systems require installation of a buried heat exchanger to utilize the nearly constant ground temperature making them more efficient than conventional air source heat pumps. However, the high installation cost for both residential and commercial applications is a major obstacle to their market penetration. Sandia National Laboratories (SNL) through its sponsors, the Department of Energy (DOE), and the Department of Defense (DOD), has embarked on a research program to find ways to reduce GHP installation costs and improve performance, thereby increasing their market penetration. The major elements of the program are: data acquisition to ...

1994-08-01

490

Evaluation of spark ignition of a gas cooktop flame  

Science.gov (United States)

One of the energy-saving devices used on gas cooking appliances to eliminate the standing pilot is a spark ignition system. For safety, an ignition system must start promptly and be active whenever flowing gas is not ignited. To minimize noise and nuisance shock hazard, ignition must occur quickly and the sparking must be stopped as soon as ignition occurs and remain off as long as the flame is present. To accomplish both of these requirements, ignition systems have been devised which use the electrical current rectification property of a flame to sense it. These systems spark whenever the gas valve is on and a flame is not present. The factors affecting the performance of a spark ignition system are numerous, complex, and transient. All of these properties make quantification of performance difficult. A system is described which can evaluate the overall performance of ignition systems over significant periods of time and varieties of operating conditions and organize the resulting ...

1996-01-01

491

EMFs run aground  

International Nuclear Information System (INIS)

Presently no one knows whether electromagnetic fields (EMFs) play a role in human cancer or other ailments, though epidemiological studies over the years have suggested that possibility. A study by the Electric Power Research Institute attempted to quantify everything it could about the magnetic environment of a home, identifying not only major sources of magnetic fields, but also their frequencies, strengths, and how they fall off with distance. Sources of a homes magnetic environment include appliances, overhead powerlines, and grounding connections to metallic water pipes. Fields will vary over time, depending on how much current is passing through the electrically conductive sources. Additional contributors to a home's magnetic background may include unusual wiring in the walls, underground power lines, and near-by high voltage transmission lines. This paper summarizes the study results, indicating weak, persistant EMFs may dominate, but small magnetic field ...

1993-08-01

492

Dosimetric characteristics of backscattered electrons in lead  

Energy Technology Data Exchange (ETDEWEB)

In electron beam therapy, tissue overdose due to electrons backscattered from lead has been profusely studied. To quantify this dose enhancement effect, an electron backscatter factor (EBF) wasdefined as the ratio of dose at the tissue-inhomogeneity interface with and without the scatterer present. The dependence of the EBF on energy at the scatterer surface is not well known for energies lower than 3 MeV which is the most frequent clinical situation. In this work, we have done Monte Carlo calculations with the GEANT code to study EBF in lead at this energy range. The applicability of this code and the developed procedure for dose estimation has been experimentally verified. The dependence of the EBF on the beam energy incident on the scatterer has been studied for different nominal beam energies incident at the phantom's surface. The results show a trend of increase of EBF with the beam energy incident on the scatterer between 0.5 and 1.5 MeV, keeping ...

2000-07-01

493

Detonating Failed Deflagration Model of Thermonuclear Supernovae II. Comparison to Observations  

CERN Document Server

We develop and demonstrate the methodology of testing multi-dimensional supernova models against observations by studying the properties of one example of the detonation from failed deflagration (DFD) explosion model of thermonuclear supernovae. Using time-dependent multi-dimensional radiative transfer calculations, we generate the synthetic broadband optical light curves, near-infrared light curves, color evolution curves, full spectral time-series, and spectropolarization of the model, as seen from various viewing angles. All model observables are critically evaluated against examples of well-observed, standard Type Ia supernovae (SNe Ia). We explore the consequences of the intrinsic model asphericity by studying the dependence of the model emission on viewing angle, and by quantifying the resulting dispersion in (and internal correlations between) various model observables. These statistical properties of the model are also evaluated against those of the ...

2006-01-01

494

Assessment of epidermal growth factor receptor (EGFR, ErbB1) and HER2 (ErbB2) protein expression levels and response to lapatinib (Tykerb, GW572016) in an expanded panel of human normal and tumour cell lines  

British Library Electronic Table of Contents (United Kingdom)

Abstract. Objective: Lapatinib (Tykerb, GW572016), a potent inhibitor of the catalytic activities of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) (ErbB2), inhibits population growth of selected EGFR and HER2 overexpressing cell lines. Previous studies with a small number of cell lines suggest a correlation between overexpression of EGFR and/or HER2 and sensitivity to growth inhibition by lapatinib; however, the precise determinants of lapatinib selectivity for tumour and/or other cells remain unclear. Materials and methods: To clarify the determinants of its selectivity in cultured cells, lapatinib-induced cell population growth inhibition and relative EGFR and HER2 protein expression were quantified in 61 different human tumour cell lines fro...

2007-01-01

495

A proposed methodology for computational fluid dynamics code verification, calibration, and validation  

Energy Technology Data Exchange (ETDEWEB)

Verification, calibration, and validation (VCV) of Computational Fluid Dynamics (CFD) codes is an essential element of the code development process. The exact manner in which code VCV activities are planned and conducted, however, is critically important. It is suggested that the way in which code validation, in particular, is often conducted--by comparison to published experimental data obtained for other purposes--is in general difficult and unsatisfactory, and that a different approach is required. This paper describes a proposed methodology for CFD code VCV that meets the technical requirements and is philosophically consistent with code development needs. The proposed methodology stresses teamwork and cooperation between code developers and experimentalists throughout the VCV process, and takes advantage of certain synergisms between CFD and experiment. A novel approach to uncertainty analysis is described which can both distinguish between and quantify ...

1995-07-01

496

A new approach towards anomalous fading correction for feldspar IRSL dating - tests on samples in field saturation  

Energy Technology Data Exchange (ETDEWEB)

Anomalous fading of the feldspar infrared stimulated luminescence (IRSL) signal hampers possibilities of using feldspar IRSL to obtain burial ages for sediments beyond the dating range of quartz optically stimulated luminescence. Here, we propose a new approach to quantify anomalous fading of the feldspar IRSL signal over geological burial times based on laboratory fading experiments. The approach builds on the description of the quantum mechanical tunnelling process recently proposed by Huntley [2006. An explanation of the power-law decay of luminescence. J. Phys. Condensed Matter 18, 1359-1365]. We show that our methods allow the construction of un-faded and natural IRSL dose-response curves as well as anomalous fading rates in field saturation. The predicted level of field saturation closely approximates the measured saturation level for five samples from fluvial deposits (Lower Rhine) known to be older than 1 Ma. The modelled anomalous fading rate in field ...

2008-02-15

497

A Risk-Based Sensor Placement Methodology  

Energy Technology Data Exchange (ETDEWEB)

A risk-based sensor placement methodology is proposed to solve the problem of optimal location of sensors or detectors to protect population against the exposure to and effects of known and/or postulated chemical, biological, and/or radiological threats. Risk is calculated as a quantitative value representing population at risk from exposure against standard exposure levels. Historical meteorological data are used to characterize weather conditions as the frequency of wind speed and direction pairs. The meteorological data drive atmospheric transport and dispersion modeling of the threats, the results of which are used to calculate risk values. Sensor locations are determined via an iterative dynamic programming algorithm whereby threats captured or detected by sensors placed in prior stages are removed from consideration in subsequent stages. In addition to the risk-based placement algorithm, the proposed methodology provides a quantification of the marginal utility of each additional ...

2008-10-01