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In terms of the kinetic theory of the interaction between the high-power short-time laser pulses with plasma based on the propagator plotting for the plasma particle distribution functions one studied the generation of the hot electrons and of the fast ions as the relativistic femtosecond laser pulses travelled through the supercritical density plasma. One performed calculations based on the various values of the laser pulse intensity, types of the multiple-charged ions, the plasma inhomogeneity degree. One studied the acceleration mechanisms both of the plasma electrons and ions

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What are the odds of time travel?

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Initial design parameters and early operational results of a 50 MeV high brightness electron linear accelerator are described. The system utilizes a radio frequency electron gun operating at a frequency of 2.856 GHz and a nominal output energy of 4.5 MeV followed by two, 2#pi#/3 mode, disc loaded, traveling wave accelerating sections. The gun cathode is photo excited with short (6 psec) laser pulses giving design peak currents of a few hundred amperes. The system will be utilized to carry out infra-red FEL studies and investigation of new high gradient accelerating structures.

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

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The Bureau of Mines recently completed peliminary studies to demonstrate the feasibility of using Ground-Penetrating Radar (GPR) for in-seam hazard detection. Investigations included air and coal tests for the purpose of checking equipment accuracy, coal penetration, and other factors such as the effects of receiver orientation. Further investigations involved using both a short pulse and a new prototype synthetic-pulse system to locate a clay vein in a coal seam using transillumination. Data were gathered on multiple travel paths, and a back-projection processing technique was then used to create a tomographic image using the calculated velocities. A computer model of the same coal seam was subsequently processed using the same tomogrpahic technique, and the results were compared with those of the actual data. Results of these preliminary studies show that GPR is feasible for use in in-seam hazard detection and point the ...

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Sep 1, 2011 ... Estimating Travel Cost Model: Spatial Approach. In: Annual Meetings of the American Agricultural Economics Association. ...

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The US Geological survey is active in measuring time of travel in streams using dye tracers. This manual describes methods of measuring time of travel of water and waterborne solutes by dye tracing. The fluorescent dyes, measuring equipment used, and field and laboratory procedures are also described. Methods of analysis and presentation to illustrate time of travel of streams are provided.

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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

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PMID:12439520

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PMID:10923545

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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...

Energy Technology Data Exchange (ETDEWEB)

This study examines the sensitivity of the travel time distribution predicted by a reference case model to (1) scale of representation of the model parameters, (2) size of the model domain, (3) correlation range of log-transmissivity, and (4) cross correlations between transmissivity and effective thickness. The basis for the reference model is the preliminary stochastic travel time model previously documented by the Basalt Waste Isolation Project. Results of this study show the following. The variability of the predicted travel times can be adequately represented when the ratio between the size of the zones used to represent the model parameters and the log-transmissivity correlation range is less than about one-fifth. The size of the model domain and the types of boundary conditions can have a strong impact on the distribution of travel times. Longer log-transmissivity correlation ranges cause larger ...

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The Federal Highway Administration (FHWA) has put a high priority on the use of existing dynamic message signs (DMS) to provide travel time estimates to the public. The Oregon Department of Transportation (ODOT) has three DMS in the Portland metropolitan ...

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)....

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

International Nuclear Information System (INIS)

Free-electron laser (FEL) amplifiers have demonstrated high efficiencies and high output power at microwave wavelengths. However, measurements and simulations have indicated that the present level of phase stability for these devices is not sufficient for driving linear accelerators. Fluctuations in the diode voltage, which is needed to accelerate the electron beam, are the largest cause of the shifts in the phase of the output power. Pulse-power technology cannot keep the voltage fluctuations less than 1/4%. However, we have found a scheme that will make the output phase much less sensitive to these fluctuations by exploiting the traveling wave nature of the FEL interaction. In this paper we study the phase stability issue by analyzing the dispersion relation for an axial FEL, in which the rf field is transversely wiggled and the electron trajectories are purely longitudinal. The advantage of using the axial FEL interaction instead of the ...

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Energy Technology Data Exchange (ETDEWEB)

Limitations of traveling wave relaying schemes for protection of overhead extra-high voltage transmission lines are investigated. A method of analysis of traveling wave phenomena for three phase transmission lines is developed in which the interdependent phase voltages and currents are decoupled into their modal counterparts, which are approximately independent. A time domain digital simulation program is used to solve the modal transmission line equations to obtain the fault induced traveling waves detected at the relay location. The frequency dependence of the aerial modes is ignored but their losses are included. A lumped element analysis method, originally developed for transient analysis of lossy coaxial cables, is adapted here to obtain approximate solution for the fault induced traveling waves of the ground mode. Excellent agreement is found between the results obtained by this method and ...

Science.gov (United States)

The traveler participated in the discussions about the physics that can be learned in the experiments being planned, those presently running, or those recently completed by a growing number of major laboratories in Europe and the USA at the 'Workshop on NN Bremsstrahlung and Polarization Observables', where many representatives of these experimental programs were present. The traveler's research in this field is supported by a DOE Grant, and she has pioneered the early theoretical NN(lambda) treatments. In addition, she visited the Vrije University to collaborate with Professor Henk Blok on proton scattering from Zr-90 and neighboring nuclei. The traveler also visited NIKEF and discussed possible future experiments of mutual interest to be done at that laboratory.

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... In the general portion of the article it states, that no more than three family members are authorized a one time travel and per diem for ...

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... including exotic species such as Hydrilla verticellata (hydrilla), Hygrophila polysperma (hygrophila), Cryptocoryne beckettii (water trumpet), leaving little space ... ...

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Low-cost fabrication of PMC composite sandwich panels, including metallic surface preparations for bonding the PMC to titanium honeycomb. ...

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o If retaining CSRS/FERS, transferred employee will be credited with accumulated sick leave o Be reimbursed for travel, transportation, relocation costs ...

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and audio technology. The exhibition will travel to muse- ums and science centers in several U.S. cities over the next 5 years. Back in the classroom, ...

British Library Electronic Table of Contents (United Kingdom)

Background. Every year, millions of people travel to countries where rabies is enzootic. However, the quality of rabies-specific information provided by travel health advisors and the extent of their knowledge about pre- and postexposure prophylaxis have not been examined on a large-scale basis up to now. Methods. 5,780 German physicians and pharmacists, who identified themselves as active travel health advisors, were chosen from a database. The selected providers were asked to complete an Internet-based questionnaire. The form requested both demographic information and the assessment of different concrete scenarios, each of which featured individuals seeking pretravel advice on rabies or appropriate postexposure treatment after returning from abroad. Results. Overall, 496 physicians and p...

International Nuclear Information System (INIS)

The dynamical decoupling (DD) aims at suppressing the decoherence by means of coherent control pulses. Even if devices exist where instantaneous pulses are an adequate approximation, experimentally a finite duration #tau#_p and a bounded amplitude are inevitable. They are the cause of additional errors which can be corrected by designing the pulse shape appropriately. The new pulse has the overall effect of an ideal, instantaneous pulse with the advantage of decoupling the spin (or qubit) from the bath up to the order O(#tau#_p"3). The limitation of the no-go theorem for #pi# pulses is avoided. Hence, the Uhrig sequence (UDD), originally thought for ideal #pi# pulses, works also for bounded control Hamiltonians. Numerical simulations show that concatenated sequences of real pulses are effective against general ...

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

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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

International Nuclear Information System (INIS)

Specificity of the pulses mean frequency measurement (the pulses being generated in a stochastic process) is described. Status of the domain of analog frequency meters is presented. Methods of increasing accuracy of such meters are discussed. (author).

UK PubMed Central (United Kingdom)

Foreign travel has been suggested to be a risk factor for the acquisition of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae. To our knowledge, this has not previously...Full Text Available

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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

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

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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

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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...

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

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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

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

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Background and ObjectivePulsed dye laser (PDL) treatment of cutaneous vascular lesions is associated with variable and unpredictable efficacy. Thus, alternative treatment...Full Text Available

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... spontaneous radiation of amplifiers within a relatively w~de range of ... pulse widths are 20-30ns, while amplified spontaneous radiation pulse ...

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... electron guns linear accelerators magnetrons multivibrators pulse generators

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.

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No abstract prepared.

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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 ...

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The great advantage of the helical ionization cooling channel (HCC) is its compact structure that enables the fast cooling of muon beam 6-dimensional phase space. This compact aspect requires a high average RF gradient, with few places that do not have cavities. Also, the muon beam is diffuse and requires an RF system with large transverse and longitudinal acceptance. A traveling wave system can address these requirements. First, the number of RF power coupling ports can be significantly reduced compared with our previous pillbox concept. Secondly, by adding a nose on the cell iris, the presence of thin metal foils traversed by the muons can possibly be avoided. We show simulations of the cooling performance of a traveling wave RF system in a HCC, including cavity geometries with inter-cell RF power couplers needed for power propagation.

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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, ...

International Nuclear Information System (INIS)

The influence of the main factors on device efficiency of pulsed liquid jet pump with gas-liquid piston is analysed, the theoretical equation and its time-averaged solution of pulsed liquid jet pump device efficiency are derived. The theoretical and experimental results show that the efficiency of transmission of energy and mass to use pulsed jet is greatly raised, compared with steady jet, in the same device of liquid jet pump. The calculating results of time-averaged efficiency of pulsed liquid jet pump are approximately in agreement with the experimental results in our and foreign countries

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Dolores Beasley Headquarters, Washington, DC July 19, 2000 (Phone: 202/358- 1753) Bill Steigerwald Goddard Space Flight Center, Greenbelt, MD (Phone: ...

UK PubMed Central (United Kingdom)

BackgroundOlder adults may find it problematic to attend hospital appointments due to the difficulty associated with travelling to, within and from a hospital facility for the purpose...Full Text Available

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A stochastic-convective reactive (SCR) transport method is developed for one-dimensional steady transport in physically heterogeneous media with nonlinear degradation. The method is free of perturbation amplitude limitations and circumvents the difficulty of scale dependence of phenomenological parameters by avoiding volume-averaged specifications of diffusive/dispersive fluxes. The transport system is conceptualized as an ensemble of independent convective-reactive streamlines, each characterized by a randomized convective velocity (or travel time). Dispersive effects are treated as a component of the randomness in the streamline velocity ensemble, so no explicit expression for hydrodynamic dispersive flux is written in the streamline transport equation. The expected value of the transport over the stream tube ensemble is obtained as an average of solutions to the reactive convection equation according to the stream tube (travel time) ...

UK PubMed Central (United Kingdom)

Recent experiments have provided new quantitative measurements of the rippling phenomenon in fields of developing myxobacteria cells. These measurements have enabled us to develop a mathematical model...Full Text Available

UK PubMed Central (United Kingdom)

We analyzed prospective data on 17,228 European patients who sought treatment at GeoSentinel sites from 1997 to 2007. Gastrointestinal illness (particularly in tourists), fever (those visiting friends...Full Text Available

Science.gov (United States)

Recent cognitive psychological research has argued that involuntary mental time travel is an important individual difference variable that has the potential to affect an individual's motivation. However, this issue has not been empirically investigated in educational settings such as teacher education. Therefore, this study aimed to explore the possible effect of involuntary mental time travel on prospective teachers' situational intrinsic motivations in the classrooms during the period of a class hour. A total of 274 prospective teachers voluntarily participated in the study. Results showed that involuntary mental time travel into the past and into the future occurred in the classrooms even during the period of a class hour. The characteristics of the prospective teachers' involuntary memories/future images were evident. Most importantly, results revealed that the teaching-related positive future images significantly and ...

Energy Technology Data Exchange (ETDEWEB)

The electric power consumption of electric cars and the demand they will pose on electric utilities are considered. The increased amount of travel will require more electric power in summer, while space heating makes larger demands in winter. This leads to nearly flat demand on electric utilities throughout the year. 5 refs.

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... Author: Vets With A Mission Subjects: vietnam, vietnam war, warfare DeweyClass: 959.7043 Resource ... Subjects: vietnam, vietnam war DeweyClass: 959.7 Resource type: bibliography, index World Travel ...

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The debate about whether or not animals have foresight has focused on whether animals can be shown to have episodic future thinking, that is the ability to travel mentally in time and see themselves in the future. This focus has distracted from consideration of other forms of foresight that animals demonstrate. We propose a framework for examining future-oriented behaviours and then discuss the evidence for future thinking in animals. In the final section we examine some perspectives of future thinking and suggest that there are future-oriented capabilities of animals that do not involve mental time travel but may yet involve future thinking which deserve further investigation. PMID:20522320

Energy Technology Data Exchange (ETDEWEB)

The control valve for a large steam turbine must be operated linearly to be run by an automatic control system in a power plant. It is, however, found that the flow increase is much greater for a given valve position change near the closed end of travel than it is near the open end. Accordingly, the desired linearization will be achieved if the valve is opened less near the closed end of travel and greater near the open end. The previous way for linearization was to utilize the cams, which is called the mechanical hydraulic control (MHC). The MHC was afterward improved by producing the nonlinear electric compensation to the nonlinear system of control valves, viz. the electro hydraulic control (EHC)

International Nuclear Information System (INIS)

A calculation on the stabilization of the sideband instability in the free electron laser (FEL) and inverse FEL (IFEL) was completed. The issue arises in connection with the use of a tapered (''variable-parameter'') undulator of extended length, such as might be used in an ''enhanced efficiency'' traveling-wave FEL or an IFEL accelerator. In addition, the FEL facility at Columbia was configured as a traveling wave amplifier for a 10-kW signal from a 24-GHz magnetron. The space charge field in the bunches of the FEL was measured. Completed work has been published.

British Library Electronic Table of Contents (United Kingdom)

The purpose of this study is to determine whether there are differences among visitors to a destination based on their golfing frequency in the previous year. By constructing a framework for understanding the golf traveller, golf and tourism industry representatives can better understand the contribution that golfers make to a destination based on factors such as satisfaction, perceived value received from the golfing experience, trip length, expenditures, travel decisions, and motivations. The results indicate that there are significant differences between golfers based on golfing frequency. Dedicated golfers are very different from infrequent and moderate golfers on three of the four variables used to profile these visitors. Findings from this research may provide golf and tourism market...

Energy Technology Data Exchange (ETDEWEB)

Relativistic electron beams are used for generating high power microwaves. These microwave sources require electron beam generators spanning significant ranges in voltage and impedance. The pulsed power technology used to generate these electron beams is presented. Electron beam generators that produce beams with pulse durations in the 10-ns to 100-ns regime consist of an energy-storage section, pulse-shaping section, and an electron beam diode. The energy-storage section is either a Marx generator or capacitor bank-pulsed transformer. The pulse shaping is done with high-voltage transmission lines. The electron beam diode is usually a cold-cathode, space-charge-limited flow device. For longer pulses (/approximately/1 ..mu..s) the energy storage and pulse chaping can be combined. Lumped-element pulse-forming networks ...

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The objective of this project is to develop improved seismic event location techniques that can be used to generate more and better quality reference events using data from local and regional seismic networks. Their approach is to extend existing methods of multiple-event location with more general models of the errors affecting seismic arrival time data, including picking errors and errors in model-based travel-times (path corrections). Toward this end, they are integrating a grid-search based algorithm for multiple-event location (GMEL) with a new parameterization of travel-time corrections and new kriging method for estimating the correction parameters from observed travel-time residuals. Like several other multiple-event location algorithms, GMEL currently assumes event-independent path corrections and is thus restricted to small event clusters. The new parameterization assumes that travel-time ...

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 ...

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 ...

International Nuclear Information System (INIS)

The time and dose characteristics of the electron and X-ray radiations of a tube, connected to a subnanosecond mega volt accelerator, are measured. By the pulse of the accelerating voltage of #>=# 600 kV with duration of #approx =# 0.3 ns the tube generates approximately 5 x 10"1"2 electrons pulse. The current amplitude equals approximately 5 kA/pulse and the radiation dose-about 5 kGy/pulse. The X-ray radiation dose from the tantalum external target constitutes 0.15 Gy/pulse. The prototypes of the electron and X-ray tubes sufficiently lower volumes, opening new applications in the technique and medicine, are developed

Energy Technology Data Exchange (ETDEWEB)

In the process of backward Raman amplification (BRA), the leading layers of the seed laser pulse can shadow the rear layers, thus weakening the effective seeding power and affecting parameters of output pulses in BRA. We study this effect numerically and also analytically by approximating the pumped pulse by the ''*-pulse'' manifold of self-similar solutions. We determine how the pumped pulse projection moves within the *-pulse manifold, and describe quantitatively the effective seeding power evolution. Our results extend the quantitative theory of BRA to regimes where the effective seeding power varies substantially during the amplification. These results might be of broader interest, since the basic equations, are general equations for resonant 3-wave interactions.

Energy Technology Data Exchange (ETDEWEB)

An electronically controllable apparatus is described which modulates a continuous wave laser beam so as to produce an output beam consisting of coherent ''pulses'' that are electronically controllable as to both pulse repetition rate and pulse width. The apparatus includes two acoustic devices positioned so that the laser beam passes through them in sequence, and apparatus or for passing sound waves through the devices to frequency shift the laser radiation as well as to diffract it. Each acoustic device such as generates sound waves containing a group of frequencies which result in spaced pulses. The spreading of a laser beam at which emanates from the first acoustic device is countered by the second acoustic device to produce a collimated, coherently pulsed, laser beam.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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).

International Nuclear Information System (INIS)

A system for real-time neutron radiography of moving objects is described. It comprise a source adapted to generate a continuous uninterrupted series of neutron pulses. Each pulse has a predetermined peak power and duration compatible with the framing times of a real-time video imaging system. A transporter moves an object to be examined to bring sequentially position selected portions of the object in the path of the pulses. Where the object itself has moving components, pulses are sequentially incident on the object. According to any dissimilarities, the object will alter the intensity of the neutrons passing therethrough. In order to record separately the changes in the neutron intensity, for each pulse, an imager is positioned to receive the neutron beam pulses which have been altered by their passage through the object and produce images indicating ...

International Nuclear Information System (INIS)

We have studied both theoretically and experimentally a new scheme of active pulse compression in a free electron laser (FEL) amplifier. The pulse compression scheme presented here is the following. A frequency-chirped pulse is injected into the FEL interaction region. Because of the high gain and narrow bandwidth of the FEL interaction, only the resonant frequency band of the pulse is actively amplified, resulting in a short pulse of high power coherent radiation at the output of the laser. For our experimental parameters (beam voltage #approx =# 150 kV, current #approx =# 5.0 A, wiggler period #approx =# 3.5 cm and gain #approx =# 10 dB), pulses of a few nanoseconds were generated at #approx =# 10 GHz after an interaction length of 2.30 m, in good agreement with theoretical expectations. For the same input pulses (width > 100 ns, ...

Energy Technology Data Exchange (ETDEWEB)

The essential mechanical and electronic parts of a beam pulsing system are described, which reaches an energy resolution of ..delta..E/E=0.1%-0.4% in the energy range from 100 eV and 10 keV.

Energy Technology Data Exchange (ETDEWEB)

This progress report presents a detailed description of the background, technology and application, and Statement of Work for the development of a coal-fired pulse combustor for residential space heating.

International Nuclear Information System (INIS)

An optical klystron is built in the 800 MeV electron storage ring at University of Science and Technology of China for harmonic super-radiation generation. In single bunch operation mode the repetition rate of the spontaneous radiation pulses is about 4.533 MHz, and the repetition rate of the seed laser pulses is about 3 Hz, while the radiation pulse duration is 300 ps. For measuring harmonic radiation a high on/off ratio ICCD is used as an optical switch to reject spontaneous radiation pulses of high repetition rate

Environmental Research Database

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International Nuclear Information System (INIS)

We report on the collision of 1.5 ps (FWHM) laser pulses traversing at 17 a short similar 7 ps (FWHM) 46.6 GeV electron bunch. The phase-locked system used to maintain the correct timing of the laser pulses and the appropriate diagnostics are described. The jitter between the laser and electron pulses is determined from the stability of the observed rate of Compton scatters and can be described by a Gaussian distribution with #sigma#_j#approx =#2.2 ps. (orig.).

Science.gov (United States)

... pulses by a 50/50 beamsplitter and recombined in space and in time inside a wafer of KDP crystal which generates a second harmonic of the ...

Science.gov (United States)

... This is achieved by the use of a unique logic circuit employing a plurality of flip-flop devices, multivibrators and AND gates. ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Compton backscattering of laser photons near the interaction point of an e"+e"- or e"-e"- collider can be used to produce a #gamma#-#gamma# or #gamma#-e"- collider. This paper describes the laser requirements, including pulse duration, intensity, energy, and wavelength, for such a collider. For most of the proposed, next generation, e"+e"- colliders, the laser wavelength should be in the near-infrared, with a pulse duration of 1 ps or less and an energy of similar 1 J per pulse. Current chirped pulse amplification laser systems in solid state lasing materials are well suited to meet these requirements. These systems are described. ((orig.)).

KoreaScience (Korea)

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Science.gov (United States)

... 1 ..... 14 High Dielectric Constant Ceramics for Use in Blumlein Transmission Lines ..... 14 ...

International Nuclear Information System (INIS)

We report on a time-resolved measurement of self-amplified spontaneous emission free-electron laser (FEL) pulses. We observed that the spikes in such FEL pulses have an intrinsic positive chirp and the energy chirp in the electron bunch mapped directly into the FEL output. The measurement also provides rich information on the statistics of the FEL pulses.

DEFF Research Database (Denmark)

We present a monolithic, self-starting, all-PM, stabilized Yb-fiber laser, pulse-compressed in a hollow-core PM photonic crystal fiber, providing the 370 fs pulses of 4 nJ energy with high mode quality.

International Nuclear Information System (INIS)

Among the investigations conducted on the space shuttle flight STS 3 March 1982 was an experiment in which a 1-keV, 100-mA electron gun was pulsed at 3.25 and 4.87 kHz. The resultant waves were measured with a broadband plasma wave receiver. At the time of flight the experimental setup was unique in that the electron beam was square wave modulated and that the shuttle offered relatively long times for in situ measurements of the ionospheric plasma response to the VLF pulsing sequences. In addition to electromagnetic response at the pulsing frequencies the waves exhibited various spectral harmonics as well as the unexpected occurrence of satellite lines around those harmonics. Both phenomena occurred with a variety of different characteristics for different pulsing sequences.

Energy Technology Data Exchange (ETDEWEB)

The detection of explosives is a notoriously difficult problem, especially at stand-off distances, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring optimal dynamic detection to exploit the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity of explosives signatures while reducing the influence of noise and the signals from background interferents in the field (increase selectivity). These goals are being addressed by operating in an optimal nonlinear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe ...

CERN Document Server

Calculations relating to two experiments that demonstrate coherent control of preformed rubidium-85 molecules in a magneto-optical trap using ultrafast laser pulses are presented. In the first experiment, it is shown that pre-associated molecules in an incoherent mixture of states can be made to oscillate coherently using a single ultrafast pulse. A novel mechanism that can transfer molecular population to more deeply bound vibrational levels is used in the second. Optimal parameters of the control pulse are presented for the application of the mechanism to molecules in a magneto-optical trap. The calculations make use of an experimental determination of the initial state of molecules photoassociated by the trapping lasers in the magneto-optical trap and use shaped pulses consistent with a standard ultrafast laser system.

International Nuclear Information System (INIS)

The advances in laser technology have made available very short and intense laser pulses which can be used to seed a high-gain single-pass free-electron laser (FEL) amplifier. With these seed pulses, a regime of the FEL interaction where the radiation evolution is simultaneously dominated by nonlinear effects (saturation) and time-dependent effects (slippage) can be explored. This regime is characterized by the propagation of a solitary wavelike pulse where the power of the optical wave grows quadratically with time, its pulse length decreases and the spectral bandwidth increases. We analyze the interplay between the field and particle dynamics of this propagation regime which was studied before and termed super-radiance. Furthermore we analyze the properties of the strong higher-order harmonic emission from this wave and its behavior when propagating in a cascade FEL. The super-radiant ...

International Nuclear Information System (INIS)

Combining the approaches given by Baldwin [Baldwin D et al. Symbolic computation of exact solutions expressible in hyperbolic and elliptic functions for nonlinear PDEs. J Symbol Comput 2004;37:669-705], Peng [Peng YZ. A polynomial expansion method and new general solitary wave solutions to KS equation. Comm Theor Phys 2003;39:641-2] and by Schuermann [Schuermann HW, Serov VS. Weierstrass' solutions to certain nonlinear wave and evolution equations. Proc progress electromagnetics research symposium, 28-31 March 2004, Pisa. p. 651-4; Schuermann HW. Traveling-wave solutions to the cubic-quintic nonlinear Schroedinger equation. Phys Rev E 1996;54:4312-20] leads to a method for finding exact travelling wave solutions of nonlinear wave and evolution equations (NLWEE). The first idea is to generalize ansaetze given by Baldwin and Peng to find elliptic solutions of NLWEEs. Secondly, conditions used by Schuermann to find physical (real and bounded) ...

Energy Technology Data Exchange (ETDEWEB)

Deformation in the overburden proves useful in deducing spatial and temporal changes in the volume of a producing reservoir. Based upon these changes we estimate diffusive travel times associated with the transient flow due to production, and then, as the solution of a linear inverse problem, the effective permeability of the reservoir. An advantage an approach based upon travel times, as opposed to one based upon the amplitude of surface deformation, is that it is much less sensitive to the exact geomechanical properties of the reservoir and overburden. Inequalities constrain the inversion, under the assumption that the fluid production only results in pore volume decreases within the reservoir. We apply the formulation to satellite-based estimates of deformation in the material overlying a thin gas production zone at the Krechba field in Algeria. The peak displacement after three years of gas production is approximately 0.5 cm, overlying the ...

Science.gov (United States)

The article draws on interpretive frameworks from diffusion research and social network analysis to explore one particular "travelling reform"--outcomes-based education--that went global. The argument is made that by virtue of studying late adopters of a travelling reform one is examining globalisation. The cases in point for late adoption are Central Asian education systems (in particular Mongolia and Kyrgyz Republic) that borrowed outcomes-based education reforms at a time when the popularity of similar reforms were already in decline in other countries, notably in New Zealand, Australia and South Africa. The emphasis of this study is on the timing of policy borrowing, and it is suggested that more attention is given to the economics of policy borrowing. (Contains 3 notes.)

International Nuclear Information System (INIS)

In this paper, a time-domain equivalent circuit method is applied to solve dispersion of coupled-cavity travelling-wave tube (CCTWT). First, the time-domain circuit equations of CCTWT coupled-cavity chain are deduced from the equivalent circuit model. Then, the equations are solved numerically by fourth-order Runge-Kutta method and a program CTTDCP is developed using MATLAB. Last, a L-band CCTWT is calculated using CTTDCP and the cavity pass-band of this tube is computed to be 1.08-1.48 GHz, which is consistent with the experimental results and the simulation results of electromagnetic code and demonstrates the validity of the time-domain equivalent circuit method. In addition, a new design method which uses the equivalent circuit method and electromagnetic simulation together to optimize the cold cavity characteristics of CCTWT is proposed. (authors)

British Library Electronic Table of Contents (United Kingdom)

The relevance of the mean retention time (MRT) of particles through the gastrointestinal tract (GIT) is well understood and MRTparticleGIT is an important parameter in digestion models. Solute markers have been used to estimate MRTsoluteGIT (or 'fluid passage') in animals, but the relevance of this measure is less evident and is usually sought in its relation to MRTparticleGIT. The ratio between the two measures indicates the degree of 'digesta washing', with little washing occurring at ratios of 1, aborad washing at ratios >1 (where the solute marker travels faster than the particle marker), and orad (retrograde) washing at ratios <1 (where the solute marker travels slower than the particle marker). We analysed digesta washing in a dataset of 98 mammalian species including man of differen...

International Nuclear Information System (INIS)

The control valve for a large steam turbine must be operated linearly to be run by an automatic control system in a power plant. It is, however, found that the flow increase is much greater for a given valve position change near the closed end of travel than it is near the open end. Accordingly, the desired linearization will be achieved if the valve is opened less near the closed end of travel and greater near the open end. The previous way for linearization was to utilize the cams, which is called the mechanical hydraulic control (MHC). The MHC was afterward improved by producing the nonlinear electric compensation to the nonlinear system of control valves, viz. the electro hydraulic control (EHC). This paper addresses the principle of linearization.

International Nuclear Information System (INIS)

TAPP-3 and 4 reactors use large number of Self Powered Neutron Detectors (SPNDs) for Neutronic lower measurement and control. To perform in-situ calibration of these detectors in select locations and to validate the reactor physics codes which predict flux at various points in the core, traveling in-core probes (TIP) are required. The TIP assembly consists of a miniature neutron sensitive detector. The detector is driven in and out of core using a mechanism which facilitates positioning of the detector anywhere inside a vertical tube (Central carrier tube of any of the six select Vertical Flux Units) in the core. TIP is driven through retractable feed mechanism for a stroke of 13 m. This paper describes the developmental efforts and the operational feedback of the retractable feed mechanism for the stroke of 13 m used at TAPP 3 and 4 reactor. (author)

Energy Technology Data Exchange (ETDEWEB)

The plastic deformation behavior of formed CICC for the superconducting Tokamac fusion device was examined and appropriate manufacturing information was provided. A relation between travel of the bending roller and spring back displacement was obtained via virtual manufacturing. The radius of CICC after forming was expressed as a function of the bend-roll travel. The maximum von Mises stress after spring back was also monitored for the SAGBO prediction. Next, the variation of the CICC cross-sectional area was examined during the first turn and during conduit bending with the largest curvature. Finally, the coil radius was measured and compared with the data generated from the virtual manufacturing. The measured data showed similar pattern as predicted one. Using the mapping function found to match with the real data, the data from the virtual manufacturing may facilitate accurate manufacturing.

Energy Technology Data Exchange (ETDEWEB)

Many solutions of General Relativity appear to allow the possibility of time travel. This was initially a fascinating discovery, but geometries of this type violate causality, a basic physical law which is believed to be fundamental. Although string theory is a proposed fundamental theory of quantum gravity, geometries with closed timelike curves have resurfaced as solutions to its low energy equations of motion. In this paper, we will study the class of solutions to low energy effective supergravity theories related to the BMPV black hole and the rotating wave-D1-D5-brane system. Time travel appears to be possible in these geometries. We will attempt to build the causality violating regions and propose that stringy effects prohibit their construction. The proposed chronology protection agent for these geometries mirrors a mechanism string theory employs to resolve a class of naked singularities. (author)

Energy Technology Data Exchange (ETDEWEB)

Both travelers were members of a nine-person US delegation that participated in an international workshop on accelerator-based 14 MeV neutron sources for fusion materials research hosted by the University of Tokyo. Presentations made at the workshop reviewed the technology developed by the FMIT Project, advances in accelerator technology, and proposed concepts for neutron sources. One traveler then participated in the initial meeting of the IEA Working Group on High Energy, High Flux Neutron Sources in which efforts were begun to evaluate and compare proposed neutron sources; the Fourth FFTF/MOTA Experimenters' Workshop which covered planning and coordination of the US-Japan collaboration using the FFTF reactor to irradiate fusion reactor materials; and held discussions with several JAERI personnel on the US-Japan collaboration on fusion reactor materials.

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 ...

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%). ...

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 ...

Energy Technology Data Exchange (ETDEWEB)

The authors investigated the application of pulsed corona discharge process to the removal of SO{sub 2} and NO{sub x} from industrial flue gas of an ioron-ore sintering plant. This study was performed on a pilot scale, which is the most advanced demonstration of this process. The flow rate of 5000 m{sup 3}/h of the flue gas was successfully treated. The electrode structure of the corona reactor is the same with that of conventional electrostatic precipitator. The authors made use of magnetic pulse compression technology to produce repetitive high voltage pulse. Pulse width (full width at half maximum) was reduced to less than 1 {micro}s by connecting a resister in parallel with the corona reactor. An inductor was added to the resister in series to minimize the loss by restricting the current flowing through the resister. By this way, they were able to deliver pulse power with peak ...

International Nuclear Information System (INIS)

A high power Free-Electron Laser (FEL) has lased at a wavelength of 22 #mu#m at the Japan Atomic Energy Research Institute (JAERI). The maximum power on a macro-pulse average is 1.7 kW, and it corresponds to an FEL energy of 160 #mu#J/micro-pulse. Extraction efficiency from the electron beam to the FEL radiation was measured to be 5.3% by an energy analyzer, when the maximum FEL power was coupled out. The rms wavelength spread was measured to be 4.6% at the same time. The extraction efficiency, in general, has a maximum value near the zero detuning length of an optical cavity, where (in contrast) the single-pass gain becomes smallest. A high peak current and a long macro-pulse duration are therefore indispensable for realizing high efficiency. The electron beam energy is 16.5 MeV, and the average current is 5.3 mA at a micro-pulse repetition rate of 10.4 MHz. The macro-pulse ...

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy's Pittsburgh Energy Technology Center (PETC) is actively pursuing the development and testing of coal-fired combustion systems for residential, commercial, and industrial market sectors. In response, MTCI initiated the development of a new combustor technology based on the principle of pulse combustion under the sponsorship of PETC (Contract No. AC22-83PC60419). The initial pulse combustor development program was conducted in three phases (MTCI, Development of a Pulsed Coal Combustor Fired with CWM, Phase III Final Report, DOE Contract No. AC22-83PC60419, November 1986). Phase I included a review of the prior art in the area of pulse combustion and the development of pulse combustor design concepts. It led to the conclusion that pulse combustors offer technical and base-of-operation advantages over conventional burners and ...

Energy Technology Data Exchange (ETDEWEB)

Ultrasound tomography is an attractive imaging method for the detection of breast cancer. The complex anatomy of the breast with its different spatial scales and material property contrasts make accurate reconstructions very challenging. This paper proposes a hybrid approach whereby Travel-of-Flight and Diffraction Tomography are combined together to achieve high-resolution and high-accuracy sound-speed reconstructions. The method is validated with several numerical phantoms.

Energy Technology Data Exchange (ETDEWEB)

The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. After subdividing subsurface into triangular element we shoot off the ray into subsurface by the Snell`s law. And then after taking the ray path which is similar to proper assumption we can calculate ...

Wastenet

...INFORMATION Diarrhoeal disease Food safety and foodborne illness Enterohaemorrhagic Escherichia coli (EHEC) Cholera WHO PROGRAMMES AND ACTIVITIES Child and Adolescent Health and Development (...FOS) Initiative for Vaccine Research (IVR) TECHNICAL INFORMATION Vaccine research: diarrhoeal diseases Cholera Water-related diseases Household water treatment and safe storage WHO Global Salm-Surv ...PUBLICATIONS Diarrhoea: child and adolescent health Diarrhoea: cholera RELATED TOPICS - Child health - Water - Food safety - Cholera - Travel - Breastfeeding ...

CERN Document Server

The transverse light clock, in uniform translatory motion, is usually adopted to prove the necessity of the relativistic time dilation, according to the invariance of the velocity of the light, while the former postulate of the Special Relativity is respected by the symmetrical behavior of the clock. In this paper it is instead demonstrated that the behavior of the moving longitudinal light clock must involve unusual Lorentz distortions of the space, travelled by the light, to respect both the postulates of the Special Relativity.

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the extrusion characteristics of magnesium alloy (AZ31), a computer simulation was attempted. Tensile properties of as-cast billet with different strain rates were incorporated into the simulation. The results showed a great change in distribution of stress and strain at near die region by the ram travel. It was found that the average grain size at longitudinal edge of the extruded sheet was smaller than that at center region, which might be attributed to recrystallization caused by severe plastic deformation. (orig.)

Science.gov (United States)

I travelled to San Jose, Costa Rica on July 8, 1990 to evaluate all of the completed elements of the ongoing feasibility study for the San Lorenzo River hydroelectric project. The feasibility study is being supported by ORNL under the Renewable Energy Applications and Training Project. The project is being studied for implementation by CONELECTRICAS, a consortium of rural electric cooperatives and the study itself is being conducted by BEL Engineering, a Costa Rican consulting firm under contract to CONELECTRICAS, USAID/PIC and NRECA.

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...

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.

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...

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...

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...

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...

Energy Technology Data Exchange (ETDEWEB)

A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.

International Nuclear Information System (INIS)

Measurements of low-energy (#approx#10"- "1"0 J) femtosecond laser pulse durations have been carried out on the basis of second-order autocorrelation function analysis. The scheme of non collinear second harmonic generation realized in KDP crystal has been used for increasing of the measurement contrast and accuracy. Proposed scheme can be used for measurements in wide enough ranges of laser pulse durations (from tens femto seconds to hundreds picoseconds) and energies. (authors)

Energy Technology Data Exchange (ETDEWEB)

There is increasing demand to functionalize meso- and nano-porous materials by coating and make the porous substrate biocompatible or environment friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. In the current work the pulsed laser deposition (PLD) method is used for coating Ni{sub 3}Al-based meso-porous membranes with diamond-like carbon (DLC) layers of high thickness homogeneity and adhesion. (orig.)

Energy Technology Data Exchange (ETDEWEB)

A small, permanent-magnet insert structure for the removal of electrons from pulsed, extracted, negative ion beams has been developed at Lawrence Berkeley National Laboratory. The device was computer modeled and designed for an extraction field strength of 3 kV/mm. The testing was carried out with a rf driven multicusp ion source optimized for the production of H{sup {minus}} ions and pulsed at a few Hz with pulse widths of several hundreds of {mu}s. It is demonstrated that the insert structure together with a collar can remove over 98{percent} of electrons from the extracted H{sup {minus}} ion beam without any significant deterioration of the H{sup {minus}} ion output. Application to other negative ion beams can be expected from this magnetic collar insert. {copyright} {ital 1996 American Institute of Physics.}

Science.gov (United States)

... at compositions below -AlP 4 the films were still unstable, hydrolysing in room air, and the long term stability of higher aluminium phosphides is in ...

International Nuclear Information System (INIS)

This study was the analyse the relationship between properties of ion nitrided Fe sintered material and parameters of plasma nitriding process. Pure fe sintered materials (relative density : 92%) were fabricated by hot-pressing and nitrided under pulsed DC plasma for 4 hours. The large number of parameters in plasma diffusion treatment allows close control of the process so that surface layers with defined microstructures and properties can be obtained. The number of micropores in nitriding layer can be reduced in pulsed DC plasma by reducing the plasma power and by varying the gas mixture. The phase constitution of compound layer of nitrided Fe sintered material were influenced by gas mixture (N_2 : H_2) and pulsed ratio (pulse on/off time ratio).

Energy Technology Data Exchange (ETDEWEB)

To measure electron reactions on a picosecond timescale the investigators developed a picosecond pulse-conductivity technique, which makes use of the electron fine-structure pulses of our LINAC (pulse width 25 vs FWHM) to produce excess electrons and now detects changes in sample conductance under optimum conditions with an instrumental response of 18 ps. This resolution is in agreement with a theoretical estimate. This technique has been successfully applied to study excess electron reactions in solvents covering a mobility range from 0.24 to 100 cm/sup 2/V/sup -1/s/sup -1/; extension to lower mobility liquids seem possible.

Energy Technology Data Exchange (ETDEWEB)

A flowing carbon dioxide laser was operated at low pressures up to 4 torr. Excitation of the laser was provided using various combinations of direct current (DC), pulsed microwave, and continuous wave (CW) microwave excitation. The microwaves were in the 2.45 GHz band and were coupled into the gas using a slow-wave interdigital transmission line. Laser output of 25 milliwatts (mw) was achieved using a DC discharge only. A combination of a DC discharge and pulsed microwaves doubled the output and resulted in some modulation. Changing the laser gas mixture and pulsed microwave field characteristics allowed some flexibility in the modulation. Lasing was not achieved with excitation from the CW microwaves alone due to the formation of localized discharges. Using pulsed microwaves to sustain the discharge and CW microwaves to pump the laser, a quasi-CW output of 55 mw was achieved.

International Nuclear Information System (INIS)

Presented are the investigation results of electrophysical and physico-mechanical properties of KLF-20, Viksint U-4-21, Viksint KT-73, UF-7-21, KG-184, KL-4, KL-16SE-305, VIAT-1 and PPK-21 sealants, irradiated with sources of continuous and pulse #gamma#-radiation, as well as pulse #gamma#-neutron radiation. It is shown that electrophysical and physico-mechanical properties of sealants after irradiation by continuous #gamma#-radiation up to 10"6 doses and pulse gamma-neutron radiation with neutron fluence of 10"1"3 neutron/cm"2 and #gamma#-radiation dose of 10"4R do not practically change. Electric conductivity and tangent of the angle of dielectric losses increase in the process of irradiation. Electric conductivity depends on irradiation type, is proportional to dose rate and does not depend on temperature and pulse duration.

Energy Technology Data Exchange (ETDEWEB)

In the rf-driven free-electron laser (FEL) at the Los Alamos National Laboratory, there are two pulsed-power rf modulators as sources for two tandem, side-coupled 20-MeV linear accelerators. The rf power used to control the cavity fields is supplied by two 5.5-MW modulating anode klystrons operating at a center frequency of 1300.2 MHz. The modulation of the 125 kV klystron is achieved by using a triode switch tube that provides a pulse width up to 300 ..mu..s and a pulse repetition rate up to 10 Hz. This paper describes the present configuration of these two duplicate systems and presents plans for meeting the requirements of future rf FEL experiments at Los Alamos. 12 refs., 5 figs.

Energy Technology Data Exchange (ETDEWEB)

Recently there has been growth, in interest in non-equilibrium interaction of half-period long optical pulses with matter. To date the optical pulses have been produced by chopping out a half-period long segment from a longer pulse using a semiconductor switch driven by a femtosecond laser. In this paper we present new methods for producing tunable ultra-short optical pulses as short as half an optical period using a free-electron laser driven by electron bunches with a duration a fraction of an optical period. Two different methods relying on the production of coherent spontaneous emission will be described. In the first method we show that when a train of ultra-short optical pulses as short as one half period. We present calculations which show that the small signal gain is unimportant in the early stages of radiation build up in the cavity when the startup process is dominated by ...

Science.gov (United States)

Electrically triggered action potentials in the giant alga Chara corallina are associated with a transient rise in the concentration of free Ca(2)+ in the cytoplasm (Ca(2)+(cyt)). The present measurements of Ca(2)+(cyt) during membrane excitation show that stimulating pulses of low magnitude (subthreshold pulse) had no perceivable effect on Ca(2)+(cyt). When the strength of a pulse exceeded a narrow threshold (suprathreshold pulse) it evoked the full extent of the Ca(2)+(cyt) elevation. This suggests an all-or-none mechanism for Ca(2)+ mobilization. A transient calcium rise could also be induced by one subthreshold pulse if it was after another subthreshold pulse of the same kind after a suitable interval, i.e., not closer than a few 100 ms and not longer than a few seconds. This dependency of Ca(2)+ mobilization on single and double pulses ...

British Library Electronic Table of Contents (United Kingdom)

Effect of Abdominal Active Can on DFTs. Introduction: Many patients with implantable cardioverter defibrillators (ICDs) have older lead systems, which are usually not replaced at the time of pulse generator replacement unless a malfunction is noted. Therefore, optimization of defibrillation with these lead systems is clinically important. The objective of this prospective study was to determine if an active abdominal pulse generator (Can) affects chronic defibrillation thresholds (DFTs) with a dual-coil, transvenous ICD lead system. Methods and Results: The study population consisted of 39 patients who presented for routine abdominal pulse generator replacement. Each patient underwent two assessments of DFT using a step-down protocol, with the order of testing randomized. The distal right ...

International Nuclear Information System (INIS)

Mini-LIA is a miniature of a linear induction accelerator developed by China Academy of Engineering Physics and Tsinghua University in 2007. It has been constructed with a thermionic cathode in an electron injector and a metglas core in the induction accelerator cavities. A double-pulsed electron beam was produced for the first time in China on the Mini-LIA with a thermionic cathode in the electron gun and a metglas core in the induction accelerator cavities. A double-pulsed beam current of more than 1.1A was obtained on condition of 80 kV double-pulsed high voltage produced by pulsed power system supplying to the injector and accelerating modules. Some primary experiments for measuring the parameters of Mini-LIA has been performed, and some beam characterizations of Mini-LIA are presented. Further improvement is underway. (authors)

Energy Technology Data Exchange (ETDEWEB)

The heating and current drive systems are being developed to support long pulse, high {beta}, advanced tokamak fusion physics experiments in the KSTAR tokamak. The heating and current drive systems consisting of neutral beam injection (NBI), ion cyclotron waves (ICRF), lower hybrid waves (LHCD) and electron cyclotron waves (ECH/ECCD) have been designed to operate for pulse lengths up to 300 sec and to provide a range of control functions including current drive and profile control. Development of key technologies for high power, long pulse operation has been on going. Substantial progress has been made on areas such as RF launchers, ion source, and high power supplies.

Science.gov (United States)

... is a standard in the utility industry which is used to study switching transients on power distribution networks and high-voltage transmission lines. ...

International Nuclear Information System (INIS)

During a Workshop on Gamma-Gamma Colliders in Lawrence Berkeley Laboratory, it was pointed out that an 1-#mu#m laser that can produce 1-J, 1-ps pulses at a few hundred hertz is required. With high-power scalability and ease of formatting, an FEL can be a promising candidate for such a laser. The authors propose an FEL scheme based on chirped-pulsed regenerative amplification to achieve this high peak-power laser. The 1-ps pulse of a solid-state laser will be stretched, amplified, and recompressed to achieve the high peak power. The system is relatively simple and consists of mostly components that have already been demonstrated. This paper will describe the proposal and the important issues of such a scheme.

Science.gov (United States)

... Multivibrators were used in the first model, which is called the "MV Model." Mwe second model, "1ST Model," has a saw-toothed voltage. ...

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

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