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1

Highly reproducible chronoamperometric analysis in microdroplets.  

PubMed

Here we report a method for highly reproducible chronoamperometric analysis of the contents of microdroplets. Aqueous microdroplets having volumes on the order of 1 nL and separated by a fluorocarbon solvent are generated within a microfluidic device using a T-shaped junction. The key finding is that stable and reproducible quasi-steady-state currents are observed if the electrochemical measurements are made in a narrowed segment of a microchannel. Under these conditions, the microdroplets are stretched, here by a factor of 10, leading to desirable intradroplet mass transfer characteristics. Microdroplet frequencies up to 0.67 s(-1) are accessible using this method. The quasi-steady-state currents resulting from chronoamperometric analysis of microdroplets containing 1.0 mM Ru(NH3)6(3+) have relative standard deviations of just 1.8% and 2.8% at flow rates of 30 nL min(-1) and 60 nL min(-1), respectively. Importantly, the design of the microelectrochemical device ensures direct contact between intradroplet redox molecules and the electrode surface. That is, the fluorocarbon between microdroplets does interfere with inner-sphere electrocatalytic processes such as the oxygen reduction reaction. Finite-element simulations are presented that are in accord with the experimental findings. PMID:23386119

Liu, Hong; Crooks, Richard M

2013-04-01

2

Reproducible, high performance patch antenna array apparatus and method of fabrication  

DOEpatents

A reproducible, high-performance patch antenna array apparatus includes a patch antenna array provided on a unitary dielectric substrate, and a feed network provided on the same unitary substrate and proximity coupled to the patch antenna array. The reproducibility is enhanced by using photolithographic patterning and etching to produce both the patch antenna array and the feed network.

Strassner, II, Bernd H. (Albuquerque, NM)

2007-01-23

3

Producing and Re/Producing the Global University in the 21st Century: Researcher Perspectives and Policy Consequences  

ERIC Educational Resources Information Center

This paper examines some aspects of current debates about what constitutes the global university in the 21st century, focusing particularly on concepts and perspectives about how the idea of a university is being produced and reproduced. As well as exploring the theoretical and empirical content of eight different analyses ranging from the…

Deem, Rosemary

2008-01-01

4

A highly reproducible rotenone model of Parkinson's disease.  

PubMed

The systemic rotenone model of Parkinson's disease (PD) accurately replicates many aspects of the pathology of human PD and has provided insights into the pathogenesis of PD. The major limitation of the rotenone model has been its variability, both in terms of the percentage of animals that develop a clear-cut nigrostriatal lesion and the extent of that lesion. The goal here was to develop an improved and highly reproducible rotenone model of PD. In these studies, male Lewis rats in three age groups (3, 7 or 12-14 months) were administered rotenone (2.75 or 3.0 mg/kg/day) in a specialized vehicle by daily intraperitoneal injection. All rotenone-treated animals developed bradykinesia, postural instability, and/or rigidity, which were reversed by apomorphine, consistent with a lesion of the nigrostriatal dopamine system. Animals were sacrificed when the PD phenotype became debilitating. Rotenone treatment caused a 45% loss of tyrosine hydroxylase-positive substantia nigra neurons and a commensurate loss of striatal dopamine. Additionally, in rotenone-treated animals, alpha-synuclein and poly-ubiquitin positive aggregates were observed in dopamine neurons of the substantia nigra. In summary, this version of the rotenone model is highly reproducible and may provide an excellent tool to test new neuroprotective strategies. PMID:19385059

Cannon, Jason R; Tapias, Victor; Na, Hye Mee; Honick, Anthony S; Drolet, Robert E; Greenamyre, J Timothy

2009-05-01

5

Accurate and highly reproducible picoliter injection system for capillary electrophoresis.  

PubMed

A novel, highly accurate sample injection system for capillary electrophoresis (CE) was developed based on an inkjet microchip capable of reproducing exact introduction volumes at the picoliter level. The difficulty in analyte discrimination using electrokinetic injection was also overcome using this injection method. The injection system consisted of an XY stage, an inkjet droplet ejection microchip, and a reservoir with a plug-in septum. To evaluate the precision of the system, a mixture of NBD-labeled amino acids consisting of Gly, L-Phe, L-Asp, and L-Ser was separated, and the performance was compared with that of traditional hydrodynamic and electrokinetic injection methods. The results demonstrated that the introduced volume highly relied on the number of droplets with low relative standard derivation (RSD) and good linear correction coefficient in the proposed injection method. In addition, a urine sample was analyzed via CE coupled with the inkjet injection system for the detection of the amino acid taurine. The concentration of urinary taurine was determined to be 2.42 ± 0.08 ?M (confidence level, 95%; RSD, 1.05%; n = 4) with a recovery of 98.92-109.54% (n = 3). These results demonstrate the inkjet injection system we developed has the potential to revolutionize capillary electrophoretic separation in practical and commercial applications that require an automated accurate injection system. PMID:23153061

Zeng, Hulie; Weng, Ying; Ikeda, Saori; Nakagawa, Yuri; Nakajima, Hizuru; Uchiyama, Katsumi

2012-12-04

6

PRODUCING HIGH CORN YIELDS.  

ERIC Educational Resources Information Center

|RESOURCE MATERIAL ON CORN PRODUCTION FOR HIGH SCHOOL VOCATIONAL AGRICULTURE AND ADULT FARMER CLASSES WAS DESIGNED BY A STATE LEVEL GROUP OF SUBJECT MATTER SPECIALISTS, TEACHER EDUCATORS, SUPERVISORS, AND TEACHERS TO HELP SOLVE PROBLEMS THAT CONFRONT CORN PRODUCERS AT PLANTING TIME. THE SUBJECT MATTER CONCERNS PLANTING TIME, DEPTH, ROW WIDTH,…

Illinois Univ., Urbana. Coll. of Agriculture.

7

A highly reproducible continuous process for hydroxyapatite nanoparticles synthesis.  

PubMed

This work presents a continuous process for producing hydroxyapatite nanoparticles (NanoXIM) in a network reactor, NETmix, fed by a calcium solution, a phosphorus solution and an alkaline solution. Hydroxyapatite is considered a biomaterial, used as: food additives and nutritional supplements; bone graft for bone replacement, growth and repair; biocements and coating of metallic implant. Some of the most recent applications include their use in cosmetics, toothpaste and in esthetical treatments for diminishing wrinkles by stimulating conjunctive tissue formation. The proposed process enables the micromixing control, which is essential to form nanometric structures, but it is also a determining factor in the crystals purity, crystallinity and morphology. The reactants distribution scheme at the inlet of the reactor and along the reactor, performed continuously or varying in time, is also a crucial factor to programme the properties of reactant media along the reactor, such as the pH, the supersaturation degree, the Ca/P molar ratio, and the temperature. The calcium phosphate nanoparticles suspension that exits the reactor is submitted to further aging, separation, drying, sintering and milling processes. PMID:19504858

Gomes, Paulo J; Silva, Viviana M T M; Quadros, Paulo A; Dias, Madalena M; Lopes, José C B

2009-06-01

8

Method for reproducibly preparing a low-melting high-carbon yield precursor  

DOEpatents

The present invention is directed to a method for preparing a reproducible synthetic carbon precursor by the autoclave polymerization of indene (C.sub.9 H.sub.8) at a temperature in the range of 470.degree.-485.degree. C, and at a pressure in the range of about 1000 to about 4300 psi. Volatiles in the resulting liquid indene polymer are removed by vacuum outgassing to form a solid carbon precursor characterized by having a relatively low melting temperature, high-carbon yield, and high reproducibility which provide for the fabrication of carbon and graphite composites having strict requirements for reproducible properties.

Smith, Wesley E. (Oak Ridge, TN); Napier, Jr., Bradley (Powell, TN)

1978-01-01

9

Producing citizens, reproducing the "French race": immigration, demography, and pronatalism in early twentieth-century France.  

PubMed

This essay examines how, in the context of depopulation and mass immigration, members of the French pronatalist movement advanced a policy favouring immigrants from Italy, Spain, and Poland. Because the 'demographic crisis' created a shortage of citizens as well as workers, pronatalists held that foreign workers must also be assimilable, and able to produce French offspring. While the racial difference of colonial subjects was deemed immutable, pronatalists called for the immigration of white foreigners whose less 'modern' condition promoted fecundity, traditionalism, and gender dimorphism. Evidence is drawn from demographic studies, the press of France's largest pronatalist movement, and a pronatalist advisory committee created by the Ministry of Health in 1920. PMID:18198513

Camiscioli, E

2001-01-01

10

Highly variable spike trains underlie reproducible sensorimotor responses in the medicinal leech.  

PubMed

The nervous system of the leech is a particularly suitable model to investigate neural coding of sensorimotor responses because it allows both observation of behavior and the simultaneous measurement of a large fraction of its underlying neuronal activity. In this study, we used a combination of multielectrode recordings, videomicroscopy, and computation of the optical flow to investigate the reproducibility of the motor response caused by local mechanical stimulation of the leech skin. We analyzed variability at different levels of processing: mechanosensory neurons, motoneurons, muscle activation, and behavior. Spike trains in mechanosensory neurons were very reproducible, unlike those in motoneurons. The motor response, however, was reproducible because of two distinct biophysical mechanisms. First, leech muscles contract slowly and therefore are poorly sensitive to the jitter of motoneuron spikes. Second, the motor response results from the coactivation of a population of motoneurons firing in a statistically independent way, which reduces the variability of the population firing. These data show that reproducible spike trains are not required to sustain reproducible behaviors and illustrate how the nervous system can cope with unreliable components to produce reliable action. PMID:12486172

Zoccolan, Davide; Pinato, Giulietta; Torre, Vincent

2002-12-15

11

Efficient and reproducible high resolution spiral myocardial phase velocity mapping of the entire cardiac cycle.  

PubMed

BACKGROUND: Three-directional phase velocity mapping (PVM) is capable of measuring longitudinal, radial and circumferential regional myocardial velocities. Current techniques use Cartesian k-space coverage and navigator-gated high spatial and high temporal resolution acquisitions are long. In addition, prospective ECG-gating means that analysis of the full cardiac cycle is not possible. The aim of this study is to develop a high temporal and high spatial resolution PVM technique using efficient spiral k-space coverage and retrospective ECG-gating. Detailed analysis of regional motion over the entire cardiac cycle, including atrial systole for the first time using MR, is presented in 10 healthy volunteers together with a comprehensive assessment of reproducibility. METHODS: A navigator-gated high temporal (21 ms) and spatial (1.4 x 1.4 mm) resolution spiral PVM sequence was developed, acquiring three-directional velocities in 53 heartbeats (100% respiratory-gating efficiency). Basal, mid and apical short-axis slices were acquired in 10 healthy volunteers on two occasions. Regional and transmural early systolic, early diastolic and atrial systolic peak longitudinal, radial and circumferential velocities were measured, together with the times to those peaks (TTPs). Reproducibilities were determined as mean +/- SD of the signed differences between measurements made from acquisitions performed on the two days. RESULTS: All slices were acquired in all volunteers on both occasions with good image quality. The high temporal resolution allowed consistent detection of fine features of motion, while the high spatial resolution allowed the detection of statistically significant regional and transmural differences in motion. Colour plots showing the regional variations in velocity over the entire cardiac cycle enable rapid interpretation of the regional motion within any given slice. The reproducibility of peak velocities was high with the reproducibility of early systolic, early diastolic and atrial systolic peak radial velocities in the mid slice (for example) being -0.01 +/- 0.36, 0.20 +/- 0.56 and 0.14 +/- 0.42 cm/s respectively. Reproducibility of the corresponding TTP values, when normalised to a fixed systolic and diastolic length, was also high (-13.8 +/- 27.4, 1.3 +/- 21.3 and 3.0 +/- 10.9 ms for early systolic, early diastolic and atrial systolic respectively). CONCLUSIONS: Retrospectively gated spiral PVM is an efficient and reproducible method of acquiring 3-directional, high resolution velocity data throughout the entire cardiac cycle, including atrial systole. PMID:23587250

Simpson, Robin; Keegan, Jennifer; Firmin, David

2013-04-15

12

Efficient and reproducible high resolution spiral myocardial phase velocity mapping of the entire cardiac cycle  

PubMed Central

Background Three-directional phase velocity mapping (PVM) is capable of measuring longitudinal, radial and circumferential regional myocardial velocities. Current techniques use Cartesian k-space coverage and navigator-gated high spatial and high temporal resolution acquisitions are long. In addition, prospective ECG-gating means that analysis of the full cardiac cycle is not possible. The aim of this study is to develop a high temporal and high spatial resolution PVM technique using efficient spiral k-space coverage and retrospective ECG-gating. Detailed analysis of regional motion over the entire cardiac cycle, including atrial systole for the first time using MR, is presented in 10 healthy volunteers together with a comprehensive assessment of reproducibility. Methods A navigator-gated high temporal (21 ms) and spatial (1.4?×?1.4 mm) resolution spiral PVM sequence was developed, acquiring three-directional velocities in 53 heartbeats (100% respiratory-gating efficiency). Basal, mid and apical short-axis slices were acquired in 10 healthy volunteers on two occasions. Regional and transmural early systolic, early diastolic and atrial systolic peak longitudinal, radial and circumferential velocities were measured, together with the times to those peaks (TTPs). Reproducibilities were determined as mean?±?SD of the signed differences between measurements made from acquisitions performed on the two days. Results All slices were acquired in all volunteers on both occasions with good image quality. The high temporal resolution allowed consistent detection of fine features of motion, while the high spatial resolution allowed the detection of statistically significant regional and transmural differences in motion. Colour plots showing the regional variations in velocity over the entire cardiac cycle enable rapid interpretation of the regional motion within any given slice. The reproducibility of peak velocities was high with the reproducibility of early systolic, early diastolic and atrial systolic peak radial velocities in the mid slice (for example) being ?0.01?±?0.36, 0.20?±?0.56 and 0.14?±?0.42 cm/s respectively. Reproducibility of the corresponding TTP values, when normalised to a fixed systolic and diastolic length, was also high (?13.8?±?27.4, 1.3?±?21.3 and 3.0?±?10.9 ms for early systolic, early diastolic and atrial systolic respectively). Conclusions Retrospectively gated spiral PVM is an efficient and reproducible method of acquiring 3-directional, high resolution velocity data throughout the entire cardiac cycle, including atrial systole.

2013-01-01

13

Cosputtered composition-spread reproducibility established by high-throughput x-ray fluorescence  

SciTech Connect

We describe the characterization of sputtered yttria-zirconia composition spread thin films by x-ray fluorescence (XRF). We also discuss our automated analysis of the XRF data, which was collected in a high throughput experiment at the Cornell High Energy Synchrotron Source. The results indicate that both the composition reproducibility of the library deposition and the composition measurements have a precision of better than 1 atomic percent.

Gregoire, John M.; Dale, Darren; Kazimirov, Alexander; DiSalvo, Francis J.; Dover, R. Bruce van [Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States); Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14853 (United States); Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853 (United States); Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853 (United States)

2010-09-15

14

Reproducibility and biases in high field brain diffusion MRI: An evaluation of acquisition and analysis variables.  

PubMed

Diffusion tensor imaging (DTI) of in-vivo human brain provides insights into white matter anatomical connectivity, but little is known about measurement difference biases and reliability of data obtained with last generation high field scanners (>3T) as function of MRI acquisition and analyses variables. Here we assess the impact of acquisition (voxel size: 1.8×1.8×1.8, 2×2×2 and 2.5×2.5×2.5mm(3), b-value: 700, 1000 and 1300s/mm(2)) and analysis variables (within-session averaging and co-registration methods) on biases and test-retest reproducibility of some common tensor derived quantities like fractional anisotropy (FA), mean diffusivity (MD), axial and radial diffusivity in a group of healthy subjects at 4T in three regions: arcuate fasciculus, corpus callosum and cingulum. Averaging effects are also evaluated on a full-brain voxel based approach. The main results are: i) group FA and MD reproducibility errors across scan sessions are on average double of those found in within-session repetitions (?1.3 %), regardless of acquisition protocol and region; ii) within-session averaging of two DTI acquisitions does not improve reproducibility of any of the quantities across sessions at the group level, regardless of acquisition protocol; iii) increasing voxel size biased MD, axial and radial diffusivities to higher values and FA to lower values; iv) increasing b-value biased all quantities to lower values, axial diffusivity showing the strongest effects; v) the two co-registration methods evaluated gave similar bias and reproducibility results. Altogether these results show that reproducibility of FA and MD is comparable to that found at lower fields, not significantly dependent on pre-processing and acquisition protocol manipulations, but that the specific choice of acquisition parameters can significantly bias the group measures of FA, MD, axial and radial diffusivities. PMID:23623031

Papinutto, Nico Dario; Maule, Francesca; Jovicich, Jorge

2013-04-24

15

Rapidly-dissolvable microneedle patches via a highly scalable and reproducible soft lithography approach.  

PubMed

Microneedle devices for transdermal drug delivery have recently become an attractive method to overcome the diffusion-limiting epidermis and effectively transport therapeutics to the body. Here, we demonstrate the fabrication of highly reproducible and completely dissolvable polymer microneedles on flexible water-soluble substrates. These biocompatible microneedles (made by using a soft lithography process known as PRINT) showed efficacy in piercing both murine and human skin samples and delivering a fluorescent drug surrogate to the tissue. PMID:23893866

Moga, Katherine A; Bickford, Lissett R; Geil, Robert D; Dunn, Stuart S; Pandya, Ashish A; Wang, Yapei; Fain, John H; Archuleta, Christine F; O'Neill, Adrian T; Desimone, Joseph M

2013-07-29

16

The Lhc Cryomagnet Supports in Glass-Fiber Reinforced Epoxy: a Large Scale Industrial Production with High Reproducibility in Performance  

NASA Astrophysics Data System (ADS)

The about 1700 LHC main ring super-conducting magnets are supported within their cryostats on 4700 low heat in leak column-type supports. The supports were designed to ensure a precise and stable positioning of the heavy dipole and quadrupole magnets while keeping thermal conduction heat loads within budget. A trade-off between mechanical and thermal properties, as well as cost considerations, led to the choice of glass fibre reinforced epoxy (GFRE). Resin Transfer Moulding (RTM), featuring a high level of automation and control, was the manufacturing process retained to ensure the reproducibility of the performance of the supports throughout the large production. The Spanish aerospace company EADS-CASA Espacio developed the specific RTM process, and produced the total quantity of supports between 2001 and 2004. This paper describes the development and the production of the supports, and presents the production experience and the achieved performance.

Poncet, A.; Struik, M.; Trigo, J.; Parma, V.

2008-03-01

17

A Novel Highly Reproducible and Lethal Nonhuman Primate Model for Orthopox Virus Infection  

PubMed Central

The intentional re-introduction of Variola virus (VARV), the agent of smallpox, into the human population is of great concern due its bio-terroristic potential. Moreover, zoonotic infections with Cowpox (CPXV) and Monkeypox virus (MPXV) cause severe diseases in humans. Smallpox vaccines presently available can have severe adverse effects that are no longer acceptable. The efficacy and safety of new vaccines and antiviral drugs for use in humans can only be demonstrated in animal models. The existing nonhuman primate models, using VARV and MPXV, need very high viral doses that have to be applied intravenously or intratracheally to induce a lethal infection in macaques. To overcome these drawbacks, the infectivity and pathogenicity of a particular CPXV was evaluated in the common marmoset (Callithrix jacchus). A CPXV named calpox virus was isolated from a lethal orthopox virus (OPV) outbreak in New World monkeys. We demonstrated that marmosets infected with calpox virus, not only via the intravenous but also the intranasal route, reproducibly develop symptoms resembling smallpox in humans. Infected animals died within 1–3 days after onset of symptoms, even when very low infectious viral doses of 5×102 pfu were applied intranasally. Infectious virus was demonstrated in blood, saliva and all organs analyzed. We present the first characterization of a new OPV infection model inducing a disease in common marmosets comparable to smallpox in humans. Intranasal virus inoculation mimicking the natural route of smallpox infection led to reproducible infection. In vivo titration resulted in an MID50 (minimal monkey infectious dose 50%) of 8.3×102 pfu of calpox virus which is approximately 10,000-fold lower than MPXV and VARV doses applied in the macaque models. Therefore, the calpox virus/marmoset model is a suitable nonhuman primate model for the validation of vaccines and antiviral drugs. Furthermore, this model can help study mechanisms of OPV pathogenesis.

Kramski, Marit; Matz-Rensing, Kerstin; Stahl-Hennig, Christiane; Kaup, Franz-Josef; Nitsche, Andreas; Pauli, Georg; Ellerbrok, Heinz

2010-01-01

18

A novel highly reproducible and lethal nonhuman primate model for orthopox virus infection.  

PubMed

The intentional re-introduction of Variola virus (VARV), the agent of smallpox, into the human population is of great concern due its bio-terroristic potential. Moreover, zoonotic infections with Cowpox (CPXV) and Monkeypox virus (MPXV) cause severe diseases in humans. Smallpox vaccines presently available can have severe adverse effects that are no longer acceptable. The efficacy and safety of new vaccines and antiviral drugs for use in humans can only be demonstrated in animal models. The existing nonhuman primate models, using VARV and MPXV, need very high viral doses that have to be applied intravenously or intratracheally to induce a lethal infection in macaques. To overcome these drawbacks, the infectivity and pathogenicity of a particular CPXV was evaluated in the common marmoset (Callithrix jacchus).A CPXV named calpox virus was isolated from a lethal orthopox virus (OPV) outbreak in New World monkeys. We demonstrated that marmosets infected with calpox virus, not only via the intravenous but also the intranasal route, reproducibly develop symptoms resembling smallpox in humans. Infected animals died within 1-3 days after onset of symptoms, even when very low infectious viral doses of 5x10(2) pfu were applied intranasally. Infectious virus was demonstrated in blood, saliva and all organs analyzed.We present the first characterization of a new OPV infection model inducing a disease in common marmosets comparable to smallpox in humans. Intranasal virus inoculation mimicking the natural route of smallpox infection led to reproducible infection. In vivo titration resulted in an MID(50) (minimal monkey infectious dose 50%) of 8.3x10(2) pfu of calpox virus which is approximately 10,000-fold lower than MPXV and VARV doses applied in the macaque models. Therefore, the calpox virus/marmoset model is a suitable nonhuman primate model for the validation of vaccines and antiviral drugs. Furthermore, this model can help study mechanisms of OPV pathogenesis. PMID:20454688

Kramski, Marit; Mätz-Rensing, Kerstin; Stahl-Hennig, Christiane; Kaup, Franz-Josef; Nitsche, Andreas; Pauli, Georg; Ellerbrok, Heinz

2010-04-29

19

A highly sensitive and reproducible HCV RNA hybridization method valuable for antiviral drug discovery.  

PubMed

Real-time RT-PCR and Northern blot are employed for the measurement of HCV RNA but suffer from multiple purification steps, high cost, and relatively large variability. In this study, a hybridization method for HCV RNA detection is described. This method does not need RNA purification, and is sensitive enough to detect HCV RNA present in replicon cellular lysates harvested from a single well of a 96-well plate. Fixation of RNA by UV cross-linking is crucial for this sensitivity. A linear relationship exists between hybridization signal and cell density ranging from 10(5) to as few as 300 cells per well. The signal-to-background ratio is greater than 40 and the Z factor is above 0.7. Using several known anti-HCV agents, dose-response curves and EC(50) values generated from hybridization were similar to those obtained from a luciferase assay. This method has been successfully applied to replicons of different HCV subtypes and hepatitis B virus in our laboratory. In summary, this hybridization assay is sensitive, highly reproducible, easy to handle, and a valuable tool for antiviral drug discovery. PMID:18466983

Zhao, Yongsen; Sanchez, Amy; Nie, Xingtie; Liu, Dongmei; Hou, Xiaohong; Fabrycki, Joanne; Phadke, Avinash; Deshpande, Milind; Huang, Mingjun; Yang, Wengang

2008-05-08

20

Repeated Assessment by High-Throughput Assay Demonstrates that Sperm DNA Methylation Levels Are Highly Reproducible  

PubMed Central

Objective To assess reliability of high-throughput assay of sperm DNA methylation. Design Observational study comparing DNA methylation of sperm isolated from three divided and twelve longitudinally collected semen samples. Setting Academic Medical Center Patients One man undergoing screening semen analysis during evaluation of the infertile couple and two healthy fertile male volunteers. Interventions Spermatozoa were separated from seminal plasma and somatic cells using gradient separation. DNA was extracted from spermatozoa, and DNA methylation was assessed at 1,505 DNA-sequence specific sites. Main Outcome Measures Repeatability of sperm DNA methylation measures, estimated by correlation coefficients. Results DNA methylation levels were highly correlated within matched sets of divided samples (all r?0.97) and longitudinal samples (average r=0.97). Conclusions The described methodology reliably assesses methylation of sperm DNA at large numbers of sites. Methylation profiles were consistent over time. High-throughput assessment of sperm DNA methylation is a promising tool for studying the role of epigenetic state in male fertility.

Cortessis, Victoria K.; Siegmund, Kimberly; Houshdaran, Sahar; Laird, Peter W.; Sokol, Rebecca Z.

2011-01-01

21

DNA-DNA hybridization phylogeny of sand dollars and highly reproducible extent of hybridization values.  

PubMed

A DNA hybridization phylogeny of four sand dollars using a sea biscuit as an outgroup is presented. The study is unusual in that the normalized percent hybridization (NPH) values were all less than 50%, yet the same topology was obtained regardless of which distance metric was used, i.e., whether reciprocal distances were averaged or not, or whether or not a molecular clock was assumed. The tree also appears robust under jackknifing and bootstrapping. The extent of hybridization between homologous hybrids was measured with a five- to sevenfold higher precision than is typical, and by implication NPH was also measured with a higher than normal precision. The ability to measure highly reproducible NPH values offers the possibility of examining the phylogeny of more widely divergent species than typically studied using DNA hybridization techniques, using 1/NPH as a distance metric. The hypothesis of a molecular clock within the sand dollars was rejected, adding sand dollars to the growing list of groups where significant rate variation is known. A small fraction of the sand dollar genomes hybridized with the distantly related regular sea urchin Lytechinus. These slowly evolving sequences probably represent conserved exonic components of the genome. PMID:1556742

Marshall, C R; Swift, H

1992-01-01

22

Efficient and highly reproducible capillary electrophoresis-mass spectrometry of peptides using Polybrene-poly(vinyl sulfonate)-coated capillaries.  

PubMed

The potential of capillaries noncovalently coated with a bilayer of oppositely charged polymers for the analysis of peptides by CE-MS was investigated. Bilayer coatings were produced by subsequently rinsing fused-silica capillaries with a solution of Polybrene (PB) and poly(vinyl sulfonate) (PVS). The PB-PVS coating showed to be fully compatible with MS detection causing no ionization suppression or background signals. The bilayer coating provided a considerable EOF at low pH, thereby facilitating the fast separation of peptides using a BGE of formic acid (pH 2.5). Under optimized CE-MS conditions, for enkephalin peptides high separation efficiencies were obtained with plate numbers in the range of 300,000-500,000. It is demonstrated that both the cancellation of the hydrodynamic capillary flow induced by the nebulizer gas and a sufficiently high-data acquisition rate are crucial for achieving these efficiencies. The overall performance of the CE-MS system using PB-PVS-coated capillaries was evaluated by the analysis of a tryptic digest of cytochrome c. The system provided an efficient separation of the peptide mixture, which could be effectively monitored by MS/MS detection allowing identification of at least 13 peptides within a time interval of 1.5 min. In addition, the PB-PVS coating proved to be very consistent yielding stable CE-MS patterns with highly favorable migration time reproducibilities (RSDs < 1% over a 3-day period). PMID:16736451

Catai, Jonatan R; Toraño, Javier Sastre; de Jong, Gerhardus J; Somsen, Govert W

2006-06-01

23

Electrical impedance tomography to measure pulmonary perfusion: is the reproducibility high enough for clinical practice?  

Microsoft Academic Search

A possible clinical application of electrical impedance tomography (EIT) might be to monitor changes in the pulmonary circulation, provided the reproducibility of the EIT measurement is adequate. The purpose of this study was threefold: the intra- and inter-investigator variability of repeated measurements was investigated. Three different regions of interest (ROI) were analysed to assess the optimal ROI. Twenty-four healthy subjects

H J Smit; M L Handoko; A Vonk Noordegraaf; Th J C Faes; P E Postmus; P M J M de Vries; A Boonstra

2003-01-01

24

Inexperienced clinicians can extract pathoanatomic information from MRI narrative reports with high reproducibility for use in research/quality assurance  

PubMed Central

Background Although reproducibility in reading MRI images amongst radiologists and clinicians has been studied previously, no studies have examined the reproducibility of inexperienced clinicians in extracting pathoanatomic information from magnetic resonance imaging (MRI) narrative reports and transforming that information into quantitative data. However, this process is frequently required in research and quality assurance contexts. The purpose of this study was to examine inter-rater reproducibility (agreement and reliability) among an inexperienced group of clinicians in extracting spinal pathoanatomic information from radiologist-generated MRI narrative reports. Methods Twenty MRI narrative reports were randomly extracted from an institutional database. A group of three physiotherapy students independently reviewed the reports and coded the presence of 14 common pathoanatomic findings using a categorical electronic coding matrix. Decision rules were developed after initial coding in an effort to resolve ambiguities in narrative reports. This process was repeated a further three times using separate samples of 20 MRI reports until no further ambiguities were identified (total n = 80). Reproducibility between trainee clinicians and two highly trained raters was examined in an arbitrary coding round, with agreement measured using percentage agreement and reliability measured using unweighted Kappa (k). Reproducibility was then examined in another group of three trainee clinicians who had not participated in the production of the decision rules, using another sample of 20 MRI reports. Results The mean percentage agreement for paired comparisons between the initial trainee clinicians improved over the four coding rounds (97.9-99.4%), although the greatest improvement was observed after the first introduction of coding rules. High inter-rater reproducibility was observed between trainee clinicians across 14 pathoanatomic categories over the four coding rounds (agreement range: 80.8-100%; reliability range k = 0.63-1.00). Concurrent validity was high in paired comparisons between trainee clinicians and highly trained raters (agreement 97.8-98.1%, reliability k = 0.83-0.91). Reproducibility was also high in the second sample of trainee clinicians (inter-rater agreement 96.7-100.0% and reliability k = 0.76-1.00; intra-rater agreement 94.3-100.0% and reliability k = 0.61-1.00). Conclusions A high level of radiological training is not required in order to transform MRI-derived pathoanatomic information from a narrative format to a quantitative format with high reproducibility for research or quality assurance purposes.

2011-01-01

25

Quantifying trends in disease impact to produce a consistent and reproducible definition of an emerging infectious disease.  

PubMed

The proper allocation of public health resources for research and control requires quantification of both a disease's current burden and the trend in its impact. Infectious diseases that have been labeled as "emerging infectious diseases" (EIDs) have received heightened scientific and public attention and resources. However, the label 'emerging' is rarely backed by quantitative analysis and is often used subjectively. This can lead to over-allocation of resources to diseases that are incorrectly labelled "emerging," and insufficient allocation of resources to diseases for which evidence of an increasing or high sustained impact is strong. We suggest a simple quantitative approach, segmented regression, to characterize the trends and emergence of diseases. Segmented regression identifies one or more trends in a time series and determines the most statistically parsimonious split(s) (or joinpoints) in the time series. These joinpoints in the time series indicate time points when a change in trend occurred and may identify periods in which drivers of disease impact change. We illustrate the method by analyzing temporal patterns in incidence data for twelve diseases. This approach provides a way to classify a disease as currently emerging, re-emerging, receding, or stable based on temporal trends, as well as to pinpoint the time when the change in these trends happened. We argue that quantitative approaches to defining emergence based on the trend in impact of a disease can, with appropriate context, be used to prioritize resources for research and control. Implementing this more rigorous definition of an EID will require buy-in and enforcement from scientists, policy makers, peer reviewers and journal editors, but has the potential to improve resource allocation for global health. PMID:23967065

Funk, Sebastian; Bogich, Tiffany L; Jones, Kate E; Kilpatrick, A Marm; Daszak, Peter

2013-08-14

26

Highly reproducible bactericidal activity test results by using a modified National Committee for Clinical Laboratory Standards broth macrodilution technique.  

PubMed

Bactericidal testing historically has exhibited variable reproducibility, even when prior standardized methods were employed. Several modifications to the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method are proposed to improve reproducibility. Recommended changes from the approved NCCLS guidelines (M21-A and M26-A) include omitting serum supplementation of Mueller-Hinton broth, incubating tubes at 35 degrees C for 24 h with no agitation until they are sampled, running all tests in duplicate with six dilutions instead of nine, reincubating the test for an additional 24 h to resolve discrepant bactericidal activity test results, using a single 0.1-ml sample from each clear tube for subculture, and adopting an alternate method for calculating endpoint determination. In order to test these recommendations in a clinical laboratory setting, we used the modified methodology on 224 separate tests for bactericidal activity. There were 102 serum bactericidal titer (SBT) and 122 minimum bactericidal concentration (MBC) assays performed. By defining reproducibility as agreement between duplicate tests +/- 1 dilution, we found 207 of 224 tests (92%) were reproducible at the 24-h subculture point (94% for the SBT assay and 91% for the MBC assay). When the 17 assays with discrepant results were incubated an additional 24 h for a second subculture, only 1 of 224 tests (0.4%) remained discrepant. The method used is practical for a clinical laboratory that chooses to perform bactericidal activity testing and assures a high level of reproducibility between duplicate assays. The total cost of a test was approximately $25.00. PMID:10325341

Hacek, D M; Dressel, D C; Peterson, L R

1999-06-01

27

Method of Producing High Temperature Superconductor Wires.  

National Technical Information Service (NTIS)

This patent application discloses a process for producing a superconductor wire by: (a) coating the inner surface of a steel tube with a thin layer of silver metal; (b) packing the tube with high temperature superconductor ceramic (HTSC) powder; (c) seali...

W. A. Ferrando A. P. Divecha J. Kerr

1992-01-01

28

How Resource Inequalities among High Schools Reproduce Class Advantages in College Destinations  

ERIC Educational Resources Information Center

|Previous studies argued that high school resources play a modest role in students' postsecondary destinations, but they ignored schools' programmatic resources, which provide opportunities for marks of distinction, such as Advanced Placement courses, and they focused on older cohorts of high school students who entered colleges before competition…

Klugman, Joshua

2012-01-01

29

Method for producing highly reflective metal surfaces  

DOEpatents

The invention is a novel method for producing mirror surfaces which are extremely smooth and which have high optical reflectivity. The method includes depositing, by electrolysis, an amorphous layer of nickel on an article and then diamond-machining the resulting nickel surface to increase its smoothness and reflectivity. The machined nickel surface then is passivated with respect to the formation of bonds with electrodeposited nickel. Nickel then is electrodeposited on the passivated surface to form a layer of electroplated nickel whose inside surface is a replica of the passivated surface. The mandrel then may be-re-passivated and provided with a layer of electrodeposited nickel, which is then recovered from the mandrel providing a second replica. The mandrel can be so re-used to provide many such replicas. As compared with producing each mirror-finished article by plating and diamond-machining, the new method is faster and less expensive.

Arnold, J.B.; Steger, P.J.; Wright, R.R.

1982-03-04

30

Method of producing high temperature superconductor wires  

SciTech Connect

This patent application discloses a process for producing a superconductor wire by: (a) coating the inner surface of a steel tube with a thin layer of silver metal; (b) packing the tube with high temperature superconductor ceramic (HTSC) powder; (c) sealing the tube; (d) cold working the tube to reduce its diameter; and (e) etching or dissolving away the steel tube to leave a superconductor wire comprising the silver metal coating that was on the inner surface of the steel tube as a thin silver metal sheath which encapsulates the HTSC powder. The superconductor wire can be further treated by sintering or oxygenating the HTSC powder.

Ferrando, W.A.; Divecha, A.P.; Kerr, J.

1992-01-01

31

Highly reproducible near-field optical imaging with sub-20-nm resolution based on template-stripped gold pyramids.  

PubMed

With a template-stripping fabrication technique, we demonstrate the mass fabrication of high-quality, uniform, ultrasharp (10 nm) metallic probes suitable for single-molecule fluorescence imaging, tip-enhanced Raman spectroscopy (TERS), and other near-field imaging techniques. We achieve reproducible single-molecule imaging with sub-20-nm spatial resolution and an enhancement in the detected fluorescence signal of up to 200. Similar results are obtained for TERS imaging of carbon nanotubes. We show that the large apex angle (70.5°) of our pyramidal tip is well suited to scatter the near-field optical signal into the far-field, leading to larger emission enhancement and hence to a larger quantum yield. Each gold or silver pyramidal probe is used on-demand, one at a time, and the unused tips can be stored for extended times without degradation or contamination. The high yield (>95%), reproducibility, durability, and massively parallel fabrication (1.5 million identical probes over a wafer) of the probes hold promise for reliable optical sensing and detection and for cementing near-field optical imaging and spectroscopy as a routine characterization technique. PMID:22938087

Johnson, Timothy W; Lapin, Zachary J; Beams, Ryan; Lindquist, Nathan C; Rodrigo, Sergio G; Novotny, Lukas; Oh, Sang-Hyun

2012-09-17

32

High-yield synthesis of millimetre-long, semiconducting carbon nitride nanotubes with intense photoluminescence emission and reproducible photoconductivity  

NASA Astrophysics Data System (ADS)

High-yield synthesis of millimetre-long, semiconducting nanotubular g-C3N4 with aspect ratio higher than 10 000 and strong photoluminscence emission was reported. The formation process of the nanotube was based on one-dimensional fibrous self-assembly of the protonated melamine in glycol mediated with nitric acid aqueous solution, which was subsequently thermalyzed into tubular carbon nitride through a rolling-up mechanism. The synthesized carbon nitride nanotube exhibits intense luminescent emission, fast photoresponse, and reproducible photoconductivity.High-yield synthesis of millimetre-long, semiconducting nanotubular g-C3N4 with aspect ratio higher than 10 000 and strong photoluminscence emission was reported. The formation process of the nanotube was based on one-dimensional fibrous self-assembly of the protonated melamine in glycol mediated with nitric acid aqueous solution, which was subsequently thermalyzed into tubular carbon nitride through a rolling-up mechanism. The synthesized carbon nitride nanotube exhibits intense luminescent emission, fast photoresponse, and reproducible photoconductivity. Electronic supplementary information (ESI) available: Details of experimental procedures, characterizations, and supporting images. See DOI: 10.1039/c2nr30777d

Gao, Jun; Zhou, Yong; Li, Zhaosheng; Yan, Shicheng; Wang, Nanyan; Zou, Zhigang

2012-05-01

33

Process for producing high octane gasoline  

SciTech Connect

This patent describes a process for conversion of C/sub 2/+ olefins and C/sub 3/+ paraffins to high octane C/sub 5/+ gasoline rich in methyl tertiary alkyl ether and C/sub 5/+ gasoline rich in alkylated aromatics comprising the steps of: contacting a hydrocarbon feedstock mixture containing C/sub 4/+ iso-olefins and methanol with an etherification catalyst under etherification conditions whereby an etherification effluent stream is produced comprising methyl tertiary alky ethers, unreacted methanol and hydrocarbons; passed the effluent stream to a fractionator for separation in contact with a hydrocarbon stripping medium to produce a liquid stream comprising C/sub 5/+ gasoline rich in methyl tertiary alky either and a vapor stream comprising methanol and C/sub 5/ and lower hydrocarbons; reacting step b vapor stream and a feedstock stream comprising aromatic and olefins-rich hydrocarbon in contact with shape-selective medium pore metallosilicate catalyst particles in a conversion zone at elevated temperature under olefins conversion and aromatics alkylation conditions to recover after separation reaction product streams comprising comprising a first C/sub 5/+ gasoline stream rich in alkylated aromatics, a second stream comprising C/sub 3/ and C/sub 4/ paraffinic hydrocarbons and a third steam comprising C/sub 2/ and lower hydrocarbons.

Harandi, M.N.; Owen, H.

1989-05-30

34

Process for producing high purity aromatic compounds  

SciTech Connect

High-purity C7 and/or C8 aromatic hydrocarbons are produced by reforming a C7 or C8 full boiling carbon number naphtha feed fraction or combinations thereof under reforming conditions of sufficient severity to convert essentially all of the nonaromatic portion of the naphtha feed boiling in the C7 to C8 aromatic boiling range to C7 and/or C8 aromatics, and then separating the reformate by fractional distillation into highpurity fractions of C7 and/or C8 aromatic hydrocarbons. Preferably, the C7 and/or C8 full boiling carbon number naphtha feed fraction is reformed in a plurality of reformer reaction stages with increasingly more severe conditions in order to maximize the yield of the C7 and C8 aromatics.

Mayes, W.W.

1980-05-20

35

Microalgae--novel highly efficient starch producers.  

PubMed

The freshwater alga Chlorella, a highly productive source of starch, might substitute for starch-rich terrestrial plants in bioethanol production. The cultivation conditions necessary for maximizing starch content in Chlorella biomass, generated in outdoor scale-up solar photobioreactors, are described. The most important factor that can affect the rate of starch synthesis, and its accumulation, is mean illumination resulting from a combination of biomass concentration and incident light intensity. While 8.5% DW of starch was attained at a mean light intensity of 215?µmol/(m2 s1), 40% of DW was synthesized at a mean light intensity 330?µmol/(m2 s1). Another important factor is the phase of the cell cycle. The content of starch was highest (45% of DW) prior to cell division, but during the course of division, its cellular level rapidly decreased to about 13% of DW in cells grown in light, or to about 4% in those kept in the dark during the division phase. To produce biomass with high starch content, it is necessary to suppress cell division events, but not to disturb synthesis of starch in the chloroplast. The addition of cycloheximide (1?mg/L), a specific inhibitor of cytoplasmic protein synthesis, and the effect of element limitation (nitrogen, sulfur, phosphorus) were tested. The majority of the experiments were carried out in laboratory-scale photobioreactors, where culture treatments increased starch content to up to about 60% of DW in the case of cycloheximide inhibition or sulfur limitation. When the cells were limited by phosphorus or nitrogen supply, the cellular starch content increased to 55% or 38% of DW, respectively, however, after about 20?h, growth of the cultures stopped producing starch, and the content of starch again decreased. Sulfur limited and cycloheximide-treated cells maintained a high content of starch (60% of DW) for up to 2 days. Sulfur limitation, the most appropriate treatment for scaled-up culture of starch-enriched biomass, was carried out in an outdoor pilot-scale experiment. After 120?h of growth in complete mineral medium, during which time the starch content reached around 18% of DW, sulfur limitation increased the starch content to 50% of DW. PMID:21404251

Brányiková, Irena; Maršálková, Barbora; Doucha, Ji?í; Brányik, Tomáš; Bišová, Kate?ina; Zachleder, Vilém; Vítová, Milada

2010-12-15

36

High-reproducibility, flexible conductive patterns fabricated with silver nanowire by drop or fit-to-flow method.  

PubMed

An unusual strategy was designed to fabricate conductive patterns with high reproducibility for flexible electronics by drop or fit-to-flow method. Silver nanowire (SNW) ink with surface tension of 36.9 mN/m and viscosity of 13.8 mPa s at 20°C was prepared and characterized using a field emission transmission electron microscope, X-ray diffractometer, thermogravimetric analyzer, scanning electron microscope, and four-point probe. Polydimethylsiloxane (PDMS) pattern as template was fabricated by spin coating (500 rpm), baking at 80°C for 3 h, and laser cutting. The prepared SNW ink can flow along the trench of the PDMS pattern spontaneously, especially after plasma treatment with oxygen, and show a low resistivity of 12.9 ?? cm after sintering at 125°C for 30 min. In addition, an antenna pattern was also prepared to prove the feasibility of the approach. PMID:23537333

Tao, Yu; Tao, Yuxiao; Wang, Liuyang; Wang, Biaobing; Yang, Zhenguo; Tai, Yanlong

2013-03-29

37

High-reproducibility, flexible conductive patterns fabricated with silver nanowire by drop or fit-to-flow method  

PubMed Central

An unusual strategy was designed to fabricate conductive patterns with high reproducibility for flexible electronics by drop or fit-to-flow method. Silver nanowire (SNW) ink with surface tension of 36.9 mN/m and viscosity of 13.8 mPa s at 20°C was prepared and characterized using a field emission transmission electron microscope, X-ray diffractometer, thermogravimetric analyzer, scanning electron microscope, and four-point probe. Polydimethylsiloxane (PDMS) pattern as template was fabricated by spin coating (500 rpm), baking at 80°C for 3 h, and laser cutting. The prepared SNW ink can flow along the trench of the PDMS pattern spontaneously, especially after plasma treatment with oxygen, and show a low resistivity of 12.9 ?? cm after sintering at 125°C for 30 min. In addition, an antenna pattern was also prepared to prove the feasibility of the approach.

2013-01-01

38

Shot-to-shot reproducibility in the emission of fast highly charged metal ions from a laser ion source.  

PubMed

The generation of fast highly charged metal ions with the use of the sub-nanosecond Prague Asterix Laser System, operated at a fundamental wavelength of 1315 nm, is reported. Particular attention is paid to shot-to-shot reproducibility in the ion emission. Au and Pd targets were exposed to intensities up to 5 × 10(16) W?cm(2). Above the laser intensity threshold of ?3 × 10(14) W?cm(2) the plasma is generated in a form of irregular bursts. The maximum energy of protons constituting the leading edge of the fastest burst reaches a value up to 1 MeV. The fast ions in the following bursts have energy gradually decreasing with the increasing burst number, namely, from a value of about 0.5 MeV?charge regardless of the atomic number and mass of the ionized species. PMID:22380281

Krása, J; Velyhan, A; Margarone, D; Krouský, E; Krouský, L; Jungwirth, K; Rohlena, K; Ullschmied, J; Parys, P; Ry?, L; Wo?owski, J

2012-02-01

39

Highly reproducible immunoassay of cancer markers on a gold-patterned microarray chip using surface-enhanced Raman scattering imaging.  

PubMed

This paper reports a highly reproducible immunoassay of cancer markers using surface-enhanced Raman scattering (SERS) imaging. SERS is a highly sensitive detection method but it is limited in its ability to achieve reproducible signal enhancement because of the difficulty with precisely controlling the uniform distribution of hot junctions. Consequently, inconsistent enhancement prevents the wide exploitation of SERS detection as a bio-detection tool for quantitative analysis. To resolve this problem, we explored the use of a SERS imaging-based immunoassay. For this purpose, Raman reporter-labeled hollow gold nanospheres (HGNs), were manufactured and antibodies were immobilized onto their surfaces for targeting specific antigens. After the formation of sandwich immunocomplexes using these functional HGNs on the surfaces of gold patterned wells, the SERS mapping images were measured. For target protein markers, 12×9 pixels were imaged using a Raman mapping technique in the 0-10(-4) g/mL concentration range, and the SERS signals for 66 pixels were averaged. Here, the SERS imaging-based assay shows much better correlations between concentration and intensity than does the conventional point-based assay. The limits of detection were determined to be 0.1 pg/mL and 1.0 pg/mL for angiogenin (ANG) and alpha-fetoprotein (AFP), respectively. This detection sensitivity is increased by three or four orders of magnitude over that of conventional ELISA method. The detectable dynamic range for SERS imaging (10(-4)-10(-12) g/mL) is also much wider than that for ELISA (10(-6)-10(-9) g/mL). PMID:20926277

Lee, Moonkwon; Lee, Sangyeop; Lee, Jung-hwan; Lim, Hyun-woo; Seong, Gi Hun; Lee, Eun Kyu; Chang, Soo-Ik; Oh, Chil Hwan; Choo, Jaebum

2010-09-17

40

Repeatability and interobserver reproducibility of Artemis-2 high-frequency ultrasound in determination of human corneal thickness  

PubMed Central

Background The purpose of this study was to assess the repeatability and limits of agreement of corneal thickness values measured by a high-frequency ultrasound (Artemis-2), hand-held ultrasound pachymeter (DGH-500) and a specular microscope (SP-3000P). Methods Central corneal thickness (CCT) was analyzed in this prospective randomized study that included 32 patients (18 men and 14 women) aged 21–24 years. Measurements were obtained in two sessions, one week apart, by two examiners with three devices in a randomized order. Nine measurements were taken (three with each device) on one randomly selected eye of each patient in each measurement session. The coefficient of repeatability and interobserver reproducibility for the values of each method were calculated. The limits of agreement between techniques were also evaluated. Results There were no significant differences in CCT values between sessions for each of the three devices (P > 0.05). The repeatability coefficients for the Artemis-2 (±8 ?m/±9 ?m) were superior to those of the SP-3000P (±9 ?m/±11 ?m) and DGH 500 (±12 ?m/±12 ?m) in session 1/session 2 respectively, while the interobserver reproducibility index (differences between session 1 and session 2) was superior for the SP-3000P (±17 ?m) with respect to DHG-500 (±29 ?m) and the Artemis-2 (±31 ?m). In session 1 and session 2, the limits of agreement between the techniques were 35 ?m to ?31 ?m and 34 to ?20 ?m, respectively, for DGH-500 versus Artemis-2, 73 ?m to 3 ?m and 60 ?m to 9 ?m for Artemis-2 versus SP-3000P, and 58 ?m to 22 ?m and 72 ?m to 10 ?m for DGH-500 versus SP-3000P comparisons. The DGH-500 and Artemis-2 gave similar values (P > 0.05) in both sessions, but both (Artemis-2 and DGH-500) values were significantly greater than that of the SP-3000P (P < 0.05) in both sessions. Conclusion Repeatability was comparably good for the three techniques. However, interobserver reproducibility was approximately twice as good with the SP-3000P compared with the other two devices. The Artemis-2 CCT values consistently agreed with the DGH-500 and less so with the SP-3000P. The Artemis-2 provided CCT values that were, on average, 38 ?m and 34 ?m greater than that of the SP-3000P in session 1 and session 2, respectively.

Ogbuehi, Kelechi C; Osuagwu, Uchechukwu L

2012-01-01

41

Non-invasive bone competence analysis by high-resolution pQCT: an in vitro reproducibility study on structural and mechanical properties at the human radius.  

PubMed

Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength. Bone strength depends, among others, on bone density, bone geometry and its internal architecture. With the recent introduction of a new generation high-resolution 3D peripheral quantitative computed tomography (HR-pQCT) system, direct quantification of structural bone parameters has become feasible. Furthermore, it has recently been demonstrated that bone mechanical competence can be derived from HR-pQCT based micro-finite element modeling (microFE). However, reproducibility data for HR-pQCT-derived mechanical indices is not well-known. Therefore, the aim of this study was to quantify reproducibility of HR-pQCT-derived indices. We measured 14 distal formalin-fixed cadaveric forearms three times and analyzed three different regions for each measurement. For each region cortical and trabecular parameters were determined. Reproducibility was assessed with respect to precision error (PE) and intraclass correlation coefficient (ICC). Reproducibility values were found to be best in all three regions for the full bone compartment with an average PE of 0.79%, followed by the cortical compartment (PE=1.19%) and the trabecular compartment with an average PE of 2.31%. The mechanical parameters showed similar reproducibility (PE=0.48%-2.93% for bone strength and stiffness, respectively). ICC showed a very high reproducibility of subject-specific measurements, ranging from 0.982 to 1.000, allowing secure identification of individual donors ranging from healthy to severely osteoporotic subjects. From these in vitro results we conclude that HR-pQCT derived morphometric and mechanical parameters are highly reproducible such that differences in bone structure and strength can be detected with a reproducibility error smaller than 3%; hence, the technique has a high potential to become a tool for detecting bone quality and bone competence of individual subjects. PMID:19027092

Mueller, Thomas L; Stauber, Martin; Kohler, Thomas; Eckstein, Felix; Müller, Ralph; van Lenthe, G Harry

2008-11-03

42

Highly Reproducible Bactericidal Activity Test Results by Using a Modified National Committee for Clinical Laboratory Standards Broth Macrodilution Technique  

Microsoft Academic Search

Bactericidal testing historically has exhibited variable reproducibility, even when prior standardized meth- ods were employed. Several modifications to the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method are proposed to improve reproducibility. Recommended changes from the approved NCCLS guidelines (M21-A and M26-A) include omitting serum supplementation of Mueller- Hinton broth, incubating tubes at 35°C for 24 h with

DONNA M. HACEK; DANA C. DRESSEL; LANCE R. PETERSON

1999-01-01

43

Reproducibility of MUAP properties in high-density surface EMG recordings of the upper trapezius and sternocleidomastoid muscle  

Microsoft Academic Search

The use of array surface EMG recordings for detailed assessment of motor control and muscle properties is increasing. Motor unit action potentials (MUAPs) and their properties can be extracted from these recordings. The objective of this study was to determine the reproducibility of variables obtained from array surface EMG recordings of the shoulder and neck muscles during different functional tasks.

Laura A. C. Kallenberg; Stephen Preece; Chris Nester; Hermie J. Hermens

2009-01-01

44

Late Quaternary Geomagnetic Excursions at High Northen Latitudes in Marine Sediments: Reproducing Results for the Wrong Reasons?  

NASA Astrophysics Data System (ADS)

Paleomagnetic records based on multiple sediment cores from the Arctic Ocean and Greenland Seas (e.g. Nowaczyk et al. 2003 Geophys. J. Int. 155) have suggested that several Late Quaternary geomagnetic excursions took place in this region, with the possibility of two excursions with calibrated radiocarbon ages younger than Laschamp (~40ka). During a study of the effect of the Laschamp geomagnetic excursion and the associated decrease in dipole moment on cosmogenic radionuclide production in the atmosphere, we have measured the palaeomagnetic properties of three sediment cores: JM05-31GC1 (from the Yermak Plateau), JM04-025PC2 (western Svalbard shelf) and LINK15 (Faroe-Shetland Channel). Magnetic susceptibility logs of the three cores show millennial-scale trends that can be correlated to the Dansgaard-Oeschger stadial/interstadial cycles recorded in the Greenland ice cores. Laschamp is the only geomagnetic excursion in marine isotope stage 3 that can be securely identified in the LINK15 core and it took place during D-O cycles 9 and 10, as determined from the record of magnetic susceptibility. This core was recovered from a sediment drift receiving detrital minerals from a mainly basaltic province and, therefore, the sediments contain relatively high concentrations of magnetic minerals and are characterized by stable natural remanent magnetizations. On the other hand, the two other cores were recovered from areas with a detrital source dominated by sedimentary bedrock. Thus, the sediments have a relatively low magnetic mineral concentration and relatively weak natural remanent magnetizations. In the two cores from the Arctic, a few apparent excursions were revealed by the application of successively stronger alternating field demagnetization steps. Thus, we were able to reproduce the results of Nowaczyk et al. (2003). However, we discovered that many of the apparent excursions in our cores, which are also characterized by low relative paleointensity estimates, were artifacts caused by the acquisition of anhysteretic remanent magnetizations perpendicular to the final demagnetization (vertical geographic) axis by samples with weak natural remanent magnetizations. We cannot claim that the earlier published reports of excursions were due to a similar systematic laboratory magnetization; however, we do not find conclusive evidence of an excursion younger than Laschamp (e.g. Mono) in these relatively high-resolution sediment records.

Snowball, I.; Nilsson, A.; Rasmussen, T.

2007-12-01

45

Tumour necrosis is a postoperative prognostic marker for pancreatic cancer patients with a high interobserver reproducibility in histological evaluation  

PubMed Central

Background: Tumour necrosis reflects the presence of hypoxia, which can be indicative of an aggressive tumour phenotype. The aim of this study was to investigate whether histological necrosis is a useful predictor of outcome in patients with pancreatic ductal carcinoma (PDC). Methods: We reviewed histopathological findings in 348 cases of PDC in comparison with clinicopathological information. We counted small necrotic foci (micronecrosis) as necrosis, in addition to massive necrosis that had been only defined as necrosis in previous studies. The reproducibility of identifying histological parameters was tested by asking five independent observers to blindly review 51 examples of PDC. Results: Both micronecrosis and massive necrosis corresponded to hypoxic foci expressing carbonic anhydrase IX detected by immunohistochemistry. Multivariate survival analysis showed that histological necrosis was an independent predictor of poor outcome in terms of both disease-free survival (DFS) and disease-specific survival (DSS) of PDC patients. In addition, metastatic status, and lymphatic, venous, and intrapancreatic neural invasion were independent prognostic factors for shorter DFS and metastatic status, margin status, lymphatic invasion, and intrapancreatic neural invasion were independent prognostic factors for DSS. The interobserver reproducibility of necrosis identification among the five independent observers was ‘almost perfect' (?-value of 0.87). Conclusion: Histological necrosis is a simple, accurate, and reproducible predictor of postoperative outcome in PDC patients.

Hiraoka, N; Ino, Y; Sekine, S; Tsuda, H; Shimada, K; Kosuge, T; Zavada, J; Yoshida, M; Yamada, K; Koyama, T; Kanai, Y

2010-01-01

46

Physics and Psychophysics of High-Fidelity Sound. Part III: The Components of a Sound-Reproducing System: Amplifiers and Loudspeakers.  

ERIC Educational Resources Information Center

|Described are the components for a high-fidelity sound-reproducing system which focuses on various program sources, the amplifier, and loudspeakers. Discussed in detail are amplifier power and distortion, air suspension, loudspeaker baffles and enclosures, bass-reflex enclosure, drone cones, rear horn and acoustic labyrinth enclosures, horn…

Rossing, Thomas D.

1980-01-01

47

Physics and Psychophysics of High-Fidelity Sound. Part III: The Components of a Sound-Reproducing System: Amplifiers and Loudspeakers.  

ERIC Educational Resources Information Center

Described are the components for a high-fidelity sound-reproducing system which focuses on various program sources, the amplifier, and loudspeakers. Discussed in detail are amplifier power and distortion, air suspension, loudspeaker baffles and enclosures, bass-reflex enclosure, drone cones, rear horn and acoustic labyrinth enclosures, horn…

Rossing, Thomas D.

1980-01-01

48

Absorption-based highly sensitive and reproducible biochemical oxygen demand measurement method for seawater using salt-tolerant yeast Saccharomyces cerevisiae ARIF KD-003  

Microsoft Academic Search

Salt-tolerant yeast Saccharomyces cerevisiae ARIF KD-003 was applied to highly sensitive and reproducible absorbance-based biochemical oxygen demand (BODAB-ScII) measurement for seawater. In the previous work, we have studied the BODAB-ScI method using normal Baker's yeast S. cerevisiae, and the excellent feature of the Baker's yeast as uniformly sustainable in solution could successfully be utilized. However, the BODAB-ScI responses were disappeared

Hideaki Nakamura; Yotaro Mogi; Hisashi Hattori; Yutaka Kita; Daisuke Hattori; Aki Yoshimura; Isao Karube

2008-01-01

49

Highly reproducible SERS detection in sequential injection analysis: Real time preparation and application of photo-reduced silver substrate in a moving flow-cell.  

PubMed

This paper reports an improved way for performing highly reproducible surface enhanced Raman scattering of different analytes using an automated flow system. The method uses a confocal Raman microscope to prepare SERS active silver spots on the window of a flow cell by photo-reduction of silver nitrate in the presence of citrate. Placement of the flow cell on an automated x and y stages of the Raman microscope allows to prepare a fresh spot for every new measurement. This procedure thus efficiently avoids any carry over effects which might result from adsorption of the analyte on the SERS active material and enables highly reproducible SERS measurements. For reproducible liquid handling the used sequential injection analysis system as well as the Raman microscope was operated by the flexible LabVIEW based software ATLAS developed in our group. Quantitative aspects were investigated using Cu(PAR)2 as a model analyte. Concentration down to 5×10(-6)M provided clear SERS spectra, a linear concentration dependence of the SERS intensities at 1333cm(-1) was obtained from 5×10(-5) to 1×10(-3) with a correlation coefficient r=0.999. The coefficient of variation of the method Vxo was found to be 5.6% and the calculated limit of detection 1.7×10(-5)M. The results demonstrate the potential of SERS spectroscopy to be used as a molecular specific detector in aqueous flow systems. PMID:24148503

El-Zahry, Marwa R; Genner, Andreas; Refaat, Ibrahim H; Mohamed, Horria A; Lendl, Bernhard

2013-07-31

50

Fuji, Thomson to develop, produce high-powered transistors  

Microsoft Academic Search

Some development lines pursued in making innovative products in the field of transistors for power switching are pointed out. The essential features of the new high-power modules produced are outlined.

P. Devittor

1985-01-01

51

In-vial dual extraction for direct LC-MS analysis of plasma for comprehensive and highly reproducible metabolic fingerprinting.  

PubMed

Metabolic fingerprinting of biological tissues has become an important area of research, particularly in the biomarker discovery field. Methods have inherent analytical variation, and new approaches are necessary to ensure that the vast numbers of intact metabolites present in biofluids are detected. Here, we describe an in-vial dual extraction (IVDE) method and a direct injection method that shows the total number of features recovered to be over 4500 from a single 20 ?L plasma aliquot. By applying a one-step extraction consisting of a lipophilic and hydrophilic layer within a single vial insert, we showed that analytical variation was decreased. This was achieved by reducing sample preparation stages including procedures of drying and transfers. The two phases in the vial, upper and lower, underwent HPLC-QTOF analysis on individually customized LC gradients in both positive and negative ionization modes. A 60 min lipid profiling HPLC-QTOF method for the lipophilic phase was specifically developed, enabling the separation and putative identification of fatty acids, glycerolipids, glycerophospholipids, sphingolipids, and sterols. The aqueous phase of the extract underwent direct injection onto a 45 min gradient, enabling the detection of both polarities. The IVDE method was compared to two traditional extraction methods. The first method was a two-step ether evaporation and IPA resuspension, and the second method was a methanol precipitation typically used in fingerprinting studies. The IVDE provided a 378% increase in reproducible features when compared to evaporation and a 269% increase when compared to the precipitate and inject method. As a proof of concept, the method was applied to an animal model of diabetes. A 2-fold increase in discriminant metabolites was found when comparing diabetic and control rats with IVDE. These discriminant metabolites accounted for around 600 entities, out of which 388 were identified in available databases. PMID:22702345

Whiley, Luke; Godzien, Joanna; Ruperez, Francisco J; Legido-Quigley, Cristina; Barbas, Coral

2012-07-03

52

Reproducing works of Calder  

Microsoft Academic Search

Abstract Many fine art pieces have been reproduced in digital form. The digital reproductions have been used to store and transmit the original work. In contrast, mobiles, or moving sculptures, such as those designed by Alexander Calder cannot be reproduced realistically by photographs and\\/or static images. The real characteristics of mobiles come from the motions generated by interactive external forces

Dongkyoo Lee; Chang Tae Kim; Nakhoon Baek; Jong Won Lee; Kwan Woo Ryu; James K. Hahn

2001-01-01

53

A refined, rapid and reproducible high resolution melt (HRM)-based method suitable for quantification of global LINE-1 repetitive element methylation  

PubMed Central

Background The methylation of DNA is recognized as a key mechanism in the regulation of genomic stability and evidence for its role in the development of cancer is accumulating. LINE-1 methylation status represents a surrogate measure of genome-wide methylation. Findings Using high resolution melt (HRM) curve analysis technology, we have established an in-tube assay that is linear (r > 0.9986) with a high amplification efficiency (90-105%), capable of discriminating between partcipant samples with small differences in methylation, and suitable for quantifying a wide range of LINE-1 methylation levels (0-100%)--including the biologically relevant range of 50-90% expected in human DNA. We have optimized this procedure to perform using 2 ?g of starting DNA and 2 ng of bisulfite-converted DNA for each PCR reaction. Intra- and inter-assay coefficients of variation were 1.44% and 0.49%, respectively, supporting the high reproducibility and precision of this approach. Conclusions In summary, this is a completely linear, quantitative HRM PCR method developed for the measurement of LINE-1 methylation. This cost-efficient, refined and reproducible assay can be performed using minimal amounts of starting DNA. These features make our assay suitable for high throughput analysis of multiple samples from large population-based studies.

2011-01-01

54

Assembly of polymer-gold nanostructures with high reproducibility into a monolayer film SERS substrate with 5 nm gaps for pesticide trace detection.  

PubMed

A very simple and versatile polymer assembly approach was developed. We use methoxy-mercapto-poly(ethylene glycol) (mPEG-SH) to conjugate multiple Au shapes to form dense Au monolayer films (MLFs) with 5 nm gaps and generate gigantic enhancement. The results of the discrete dipole approximation (DDA) method to calculate the local electric field distribution of the nanoparticle dimer are in agreement with the experimental data of sensitivity of multiple Au MLFs. 3D Raman spectra, relative standard deviation (RSD) calculation and Raman mapping were used to study the high-reproducibility of the assembled substrate, which is sufficient for trace pesticide residue detection. PMID:23912071

Zhou, Xia; Zhou, Fei; Liu, Honglin; Yang, Liangbao; Liu, Jinhuai

2013-10-01

55

Efficient and reproducible generation of high-expressing, stable human cell lines without need for antibiotic selection  

Microsoft Academic Search

BACKGROUND: Human cell lines are the most innovative choice of host cell for production of biopharmaceuticals since they allow for authentic posttranslational modification of therapeutic proteins. We present a new method for generating high and stable protein expressing cell lines based on human amniocytes without the requirement of antibiotic selection. RESULTS: Primary amniocytes from routine amniocentesis samples can be efficiently

Gudrun Schiedner; Sabine Hertel; Corinna Bialek; Helmut Kewes; Gero Waschütza; Christoph Volpers

2008-01-01

56

Digital etching for highly reproducible low damage gate recessing on AlGaN\\/GaN HEMTs  

Microsoft Academic Search

A room temperature digital etching technique for aluminum gallium nitride has been developed. An oxidizing agent and an acid have been used in a two step etching cycle to remove aluminum gallium nitride in approximately 5-6 Å increments. The process has been characterized to be reasonably linear and highly repeatable, offering an alternative to currently not available gate recess etch

D. Buttari; S. Heikman; S. Keller; U. K. Mishra

2002-01-01

57

Highly uniform and reproducible visible to near-infrared vertical-cavity surface-emitting lasers grown by MOVPE  

SciTech Connect

The authors present the growth and characterization of vertical-cavity surface emitting lasers (VCSELs) from visible to near-infrared wavelength grown by metalorganic vapor phase epitaxy. Discussions on the growth issue of VCSEL materials include the control on growth rate and composition using an in situ normal-incidence reflectometer, optimization of ultra-high material uniformity, and comprehensive p- and n-type doping study in AlGaAs by CCl{sub 4} and Si{sub 2}H{sub 6} over the entire Al composition range. They will also demonstrate the recent achievements of selectively-oxidized VCSELs which include the first room-temperature continuous-wave demonstration of all-AlGaAs 700-nm red VCSELs, high-performance n-side up 850-nm VCSELs, and low threshold current and low-threshold voltage 1.06 {micro}m VCSELs using InGaAs/GaAsP strain-compensated quantum wells.

Hou, H.Q.; Choquette, K.D.; Hammons, B.E.; Breiland, W.G.; Crawford, M.H.; Lear, K.L. [Sandia National Labs., Albuquerque, NM (United States). Center for Compound Semiconductors Technology

1997-05-01

58

Reproducibility of the villous component and high-grade dysplasia in colorectal adenomas <1 cm: implications for endoscopic surveillance.  

PubMed

The presence of high-grade dysplasia (HGD) or villous component (VC) defines an advanced adenoma (AA) in patients with 1 or 2 adenomas <1 cm in size. Current consensus guidelines recommend that patients with AA undergo more intense postpolypectomy surveillance. In these clinical situations, the interobserver reliability in determining VC and HGD would play a major role in the credibility of these consensus guidelines. Therefore, the purpose of this study was to evaluate interobserver variability of VC and HGD in polyps <1 cm before and after the development of consensus criteria among gastrointestinal (GI) pathologists. Five GI pathologists independently evaluated 107 colorectal adenomas <1 cm, and classified them into tubular adenomas or adenomas with a VC (A-VC) and into low-grade dysplasia or HGD. Then a consensus conference was held and consensus criteria for VC and HGD were developed by group review. The same set of 107 slides were rereviewed independently by the same 5 GI pathologists. Interobserver variability using ? statistical analysis before and after the application of consensus criteria was assessed. A 1-sided z-test was used to determine whether ? scores increased after the consensus conference. Interobserver agreement before and after the consensus conference was poor for assessment of A-VC, HGD, and AA. These data calls into question the validity of basing clinical decisions on this distinction. PMID:23348206

Mahajan, Dipti; Downs-Kelly, Erinn; Liu, Xiuli; Pai, Rish K; Patil, Deepa T; Rybicki, Lisa; Bennett, Ana E; Plesec, Thomas; Cummings, Oscar; Rex, Douglas; Goldblum, John R

2013-03-01

59

Process for producing low temperature high performance grease  

SciTech Connect

This patent describes a process for producing grease. It comprises forming lithium 12-hydroxystearate grease concentrate in polyalpholefin in the absence of mineral oil. The grease has enhanced extreme temperature performance lubricity qualities at temperatures as low as at least about {minus}100{degrees}F. and as high as at least about +250{degrees}F.

Waynick, J.A.

1989-11-07

60

Reproducing temples in Fremantle  

Microsoft Academic Search

This paper explores the production and reproduction of a sacred-soliciting built environment in the Western Australian port town of Fremantle, drawing attention to temple iconography produced in the first century of European settlement and its preservation and reproduction at the hands of local and national heritage movements since the 1970s. I show how Fremantle’s High Street solicits a sense of

Thor Kerr

2011-01-01

61

Reproducing temples in Fremantle  

Microsoft Academic Search

This paper explores the production and reproduction of a sacred-soliciting built environment in the Western Australian port town of Fremantle, drawing attention to temple iconography produced in the first century of European settlement and its preservation and reproduction at the hands of local and national heritage movements since the 1970s. I show how Fremantle’s High Street solicits a sense of

Thor Kerr

2012-01-01

62

The solubility of Fish Produced High Magnesium Calcite in Seawater  

NASA Astrophysics Data System (ADS)

Fish have been shown to produce high 10 to 30% magnesium calcite as part of the physiological mechanisms responsible for maintaining salt and water balance. The importance of this source to the marine carbon cycle is only now being considered. In this paper we report the first measurements of the solubility of this CaCO3 in seawater. The resulting solubility (pKsp = 5.85 ± 0.07) is more than two times higher than aragonite and similar to the high magnesium calcite generated on the Bahamas Banks (pKsp = 5.90). This high solubility of fish produced CaCO3 renders it soluble in near surface (<2000 m) waters contributing to the input of carbonate to surface ocean waters, and at least partially explaining the increase in total alkalinity above the aragonite saturation horizon.

Woosley, R. J.; Millero, F. J.; Grosell, M.

2011-12-01

63

High-coherence electron bunches produced by femtosecond photoionization  

NASA Astrophysics Data System (ADS)

With the development of ultrafast electron and X-ray sources it is becoming possible to study structural dynamics with atomic-level spatial and temporal resolution. Because of their short mean free path, electrons are particularly well suited for investigating surfaces and thin films, such as the challenging and important class of membrane proteins. To perform single-shot diffraction experiments on protein crystals, an ultracold electron source was proposed, based on near-threshold photoionization of laser-cooled atoms, which is capable of producing electron pulses of both high intensity and high coherence. Here we show that high coherence electron pulses can be produced by femtosecond photoionization, opening up a new regime of ultrafast structural dynamics experiments. The transverse coherence turns out to be much better than expected on the basis of the large bandwidth of the femtosecond ionization laser pulses. This surprising result can be explained by analysis of classical electron trajectories.

Engelen, W. J.; van der Heijden, M. A.; Bakker, D. J.; Vredenbregt, E. J. D.; Luiten, O. J.

2013-04-01

64

High beta plasma operation in a toroidal plasma producing device  

DOEpatents

A high beta plasma is produced in a plasma producing device of toroidal configuration by ohmic heating and auxiliary heating. The plasma pressure is continuously monitored and used in a control system to program the current in the poloidal field windings. Throughout the heating process, magnetic flux is conserved inside the plasma and the distortion of the flux surfaces drives a current in the plasma. As a consequence, the total current increases and the poloidal field windings are driven with an equal and opposing increasing current. The spatial distribution of the current in the poloidal field windings is determined by the plasma pressure. Plasma equilibrium is maintained thereby, and high temperature, high beta operation results.

Clarke, John F. (Oak Ridge, TN)

1978-01-01

65

Optimization of reproduced Morpho-blue coloration  

NASA Astrophysics Data System (ADS)

Morpho butterfly's metallic blue luster, which is produced from the butterfly's scale, has a mysterious feature. Since the scale does not contain a blue pigment, the origin of the coloration is attributed to a microscopic structure that can also explain its high reflectivity. However, it appears blue from wide angular range, which contradicts obviously the grating or multilayer. The mystery of the lack of multi-coloration has recently been explained with a peculiar nano-structure, and experimentally proven by fabricating the optical film by controlling the parameters in nanoscale. The reproduced Morpho-blue was found to be important from viewpoint of a wide variety of applications. However, optical properties of the fabricated film were found to contain still some differences with that of the Morpho-butterfly, although the basic characteristics of the Morpho-blue itself was reproduced. In order to make the artificial Morpho-blue closer to the natural one than the prototype, we attempted to optimize the artificial film structure by controlling fabrication parameters. In this process, optical simulations and micro-structural observations were taken in account. By comparing a series of films fabricated with different nano-patterns, optimized parameters were semi-empirically obtained. Also the relationship between the structural parameters and the optical properties was analyzed. The reflective characteristics of the optimized film were found to reproduce the optical properties more closely to the natural Morpho-blue than the prototypes.

Saito, Akira; Ishikawa, Yoko; Miyamura, Yusuke; Akai-Kasaya, Megumi; Kuwahara, Yuji

2007-10-01

66

Deposition method for producing silicon carbide high-temperature semiconductors  

DOEpatents

An improved deposition method for producing silicon carbide high-temperature semiconductor material comprising placing a semiconductor substrate composed of silicon carbide in a fluidized bed silicon carbide deposition reactor, fluidizing the bed particles by hydrogen gas in a mildly bubbling mode through a gas distributor and heating the substrate at temperatures around 1200.degree.-1500.degree. C. thereby depositing a layer of silicon carbide on the semiconductor substrate.

Hsu, George C. (La Crescenta, CA); Rohatgi, Naresh K. (W. Corine, CA)

1987-01-01

67

Particle longitudinal diffusion produced by a High Frequency Cavity  

SciTech Connect

A High Frequency Cavity (HFC) can be a powerful tool for the reduction of particle losses during the energy passage through the ..gamma..-transition in proton synchrotrons, via bunch dilution. In this paper we consider some aspects of bunch dilution. With an appropriately chosen frequency of phase modulation, the HFC can produce parametric resonance for particles near the bunch center. As a result, the process of dilution can be accelerated.

Kats, J.M.

1987-01-01

68

Reproducibility of a laboratory-based 40-km cycle time-trial on a stationary wind-trainer in highly trained cyclists.  

PubMed

The purpose of the present study was to examine the reproducibility of laboratory-based 40-km cycle time-trial performance on a stationary wind-trainer. Each week, for three consecutive weeks, and on different days, forty-three highly trained male cyclists (x +/- SD; age = 25 +/- 6 y; mass = 75 +/- 7 kg; peak oxygen uptake [VO (2)peak] = 64.8 +/- 5.2 ml x kg (-1) x min (-1)) performed: 1) a VO (2)peak test, and 2) a 40-km time-trial on their own racing bicycle mounted to a stationary wind-trainer (Cateye - Cyclosimulator). Data from all tests were compared using a one-way analysis of variance. Performance on the second and third 40-km time-trials were highly related (r = 0.96; p < 0.001), not significantly different (57 : 21 +/- 2 : 57 vs. 57 : 12 +/- 3 : 14 min:s), and displayed a low coefficient of variation (CV) = 0.9 +/- 0.7 %. Although the first 40-km time-trial (58 : 43 +/- 3 : 17 min:s) was not significantly different from the second and third tests (p = 0.06), inclusion of the first test in the assessment of reliability increased within-subject CV to 3.0 +/- 2.9 %. 40-km time-trial speed (km x h (-1)) was significantly (p < 0.001) related to peak power output (W; r = 0.75), VO (2)peak (l x min (-1); r = 0.53), and the second ventilatory turnpoint (l x min (-1); r = 0.68) measured during the progressive exercise tests. These data demonstrate that the assessment of 40-km cycle time-trial performance in well-trained endurance cyclists on a stationary wind-trainer is reproducible, provided the athletes perform a familiarization trial. PMID:12968204

Laursen, P B; Shing, C M; Jenkins, D G

2003-10-01

69

Human collagen 'fingerprints' produced by clostridopeptidase A digestion and high-pressure liquid chromatography.  

PubMed Central

Samples (1-2mg) of purified human type I, II and III collagens and alpha1(I) and alpha2 chains were digested with clostridiopeptidase A and the released peptides analysed by ion-exchange high-pressure liquid chromatography. Specific 'fingerprints' were produced for each type of collagen. The reproducible nature of these 'fingerprints' and the reconstitution of the type I 'fingerprint' from the 'fingerprints' of the component alpha1(I) and alpha2 chains showed that the specificity of these 'fingerprints' was related to the primary structure of each type of collagen. In addition, some of the differences observed between the 'fingerprints' of the alpha1(I) and alpha2 chains of type I collagen were shown to be suitable for the quantitative analysis of these chains.

van Der Rest, M; Cole, W G; Glorieux, F H

1977-01-01

70

[Tobacco--a highly efficient producer of vaccines].  

PubMed

Along with the depreciation of tobacco as a source of nicotine-containing commercial products, the increase of its appreciation as a potential producer of recombinant therapeutical proteins can be observed. Two species of tobacco--Nicotiana tabacum L. and N. benthamiana are easily grown by well established methods of field or green-house cultivation or cell culture, yield high biomass and soluble protein content, can be easily transformed by several methods and are not food for humans or feed for animals. Expression of foreign proteins, including vaccines, can be achieved in those plants either through stable transformation of nuclear or plastid (chloroplast) genomes or by transient transformation using infection with plant virus or bacteria--Agrobacterium tumefaciens (agroinfiltration). The most advanced mode of agrofiltration termed magnifection, which combines benefits of virus and Agrobacterium and depends on using Agrobacterium with viral pro-vectors, enables high-yield and rapid expression of therapeutical proteins, even in a few days, and can be employed on an industrial scale. Expression of many antigenic proteins, which may serve as antiviral, antibacterial, antiprotozoan and anticancer vaccines, and additionally a few autoantigens designed for the treatment of autoimunogenic diseases, like diabetes, have been achieved in tobacco. To date, a vaccine against Newcastle virus disease in poultry produced by tobacco cell culture has been approved for commercial application and several other vaccines are in advanced stage of development. The possibility of a high-level production of vaccines in tobacco against pandemic influenza or anthrax and plague due to a bioterroristic attack, as well as of individualised anticancer vaccines against non-Hodgkin's lymphoma (NHL) in a much shorter period of time than by traditional methods became realistic and hence caused increased interest in tobacco as a high-efficient producer of vaccines not only of specialistic biotechnology firms but also a big pharmaceutical corporation and a department of defence. PMID:21360963

Budzianowski, Jaromir

2010-01-01

71

Very high coercivity magnetic stripes produced by particle rotation  

SciTech Connect

This paper describes a current research program at Sandia National Laboratories whereby magnetic stripes are produced through the use of a new particle rotation technology. This new process allows the stripes to be produced in bulk and then held in a latent state so that they may be encoded at a later date. Since particle rotation is less dependent on the type of magnetic particle used, very high coercivity particles could provide a way to increase both magnetic tamper-resistance and accidental erasure protection. This research was initially funded by the Department of Energy, Office of Safeguard and Security as a portion of their Science and Technology Base Development, Advanced Security Concepts program. Current program funding is being provided by Sandia National Laboratories as part of their Laboratory Directed Research and Development program.

Naylor, R.B.

1992-12-01

72

Absorption-based highly sensitive and reproducible biochemical oxygen demand measurement method for seawater using salt-tolerant yeast Saccharomyces cerevisiae ARIF KD-003.  

PubMed

Salt-tolerant yeast Saccharomyces cerevisiae ARIF KD-003 was applied to highly sensitive and reproducible absorbance-based biochemical oxygen demand (BOD(AB-ScII)) measurement for seawater. In the previous work, we have studied the BOD(AB-ScI) method using normal Baker's yeast S. cerevisiae, and the excellent feature of the Baker's yeast as uniformly sustainable in solution could successfully be utilized. However, the BOD(AB-ScI) responses were disappeared by the existence of chloride ion as well as seawater. In the present method, uniformity in solution was also observed with S. cerevisiae ARIF KD-003, and salt-tolerance of the yeast was observed even in saturate concentration of sodium chloride. Next, characterizations of the influences of pH and incubation temperature were investigated. After optimum conditions were obtained, two calibration curves were made between 0.33 and 22 mg O2 L(-1) BOD using standard solution of glucose glutamic acid (GGA) or mixture of GGA and artificial seawater. Then, excellent reproducibility as the averages of relative standard deviation (R.S.D.(av)) in two calibration curves (nine points each) was successfully obtained at 1.10% at pure water or 1.03% at artificial seawater standard, respectively. In addition, the 3 sigma lower detection limit was calculated to be 0.07 mg O2 L(-1) BOD, and 0.11 mg O2 L(-1) BOD was experimentally detected by increase of the sample volume at 1.5-folds. The storage stability of the S. cerevisiae ARIF KD-003 was obtained at least 4 weeks. PMID:18558133

Nakamura, Hideaki; Mogi, Yotaro; Hattori, Hisashi; Kita, Yutaka; Hattori, Daisuke; Yoshimura, Aki; Karube, Isao

2008-05-13

73

APPARATUS FOR PRODUCING HIGH VELOCITY SHOCK WAVES IN GASES  

DOEpatents

>A device for producing a high-energy ionized gas region comprises an evacuated tapered insulating vessel and a substantially hemispherical insulating cap hermetically affixed to the large end of the vessel, an annular electrode having a diameter equal to and supported in the interior wall of the vessel at the large end and having a conductive portion inside the vessel, a second electrode supported at the small end of the vessel, means connected to the vessel for introducing a selected gas therein, a source of high potential having two poles. means for connecting one pole of the high potential source to the annular electrode, and means for connecting the other pole of the potential source to the second electrode.

Scott, F.R.; Josephson, V.

1960-02-01

74

Reproducibility of activation in Broca's area during covert generation of single words at high field: A single trial FMRI study at 4 T  

Microsoft Academic Search

Although functional magnetic resonance imaging (FMRI) has arguably become the most ubiquitously used imaging modality, questions remain about the reproducibility of the observed patterns of activation and the acquisition time required to achieve statistically significant and reproducible maps. In the current study, we investigated the reliability of activation in Broca's area, on both a voxel-wise and region of interest level,

Andrew R. Mayer; Jing Xu; Juliana Paré-Blagoev; Stefan Posse

2006-01-01

75

MAGNETIC METHOD FOR PRODUCING HIGH VELOCITY SHOCK WAVES IN GASES  

DOEpatents

A device is described for producing high-energy plasmas comprising a tapered shock tube of dielectric material and having a closed small end, an exceedingly low-inductance coll supported about and axially aligned with the small end of the tapered tube. an elongated multiturn coil supported upon the remninder of the exterior wall of the shock tube. a potential source and switch connected in series with the low-inductance coil, a potential source and switch connected in series with the elongated coil, means for hermetically sealing the large end of the tube, means for purging the tube of gases, and means for admitting a selected gas into the shock tube.

Josephson, V.

1960-01-26

76

Effects produced by iodine irradiation on high resistivity silicon  

NASA Astrophysics Data System (ADS)

The effects of 5 × 1011 cm-2 6+I127 ions of 28 MeV kinetic energy on high resistivity (100) Si were studied. The profile of primary defects was simulated. The defects produced by irradiation which act as traps were investigated. Thermally stimulated current measurements without externally applied bias were used, and for this the traps were charged by illuminating samples with 1000, 800, and 400 nm wavelengths. The discharge currents were recorded and modeled, and therefore the parameters of the traps were determined. The presence of I ions, heavier than Si, stopped into the target was modeled as a temperature independent electric field.

Lazanu, S.; Slav, A.; Lepadatu, A.-M.; Stavarache, I.; Palade, C.; Iordache, G.; Ciurea, M. L.

2012-12-01

77

High surface area tapes produced with functionalized graphene.  

PubMed

We describe a scalable method for producing continuous graphene networks by tape casting surfactant-stabilized aqueous suspensions of functionalized graphene sheets. Similar to all other highly connected graphene-containing networks, the degree of overlap between the sheets controls the tapes' electrical and mechanical properties. However, unlike other graphene-containing networks, the specific surface area of the cast tapes remains high (>400 m(2)·g(-1)). Exhibiting apparent densities between 0.15 and 0.51 g·cm(-3), with electrical conductivities up to 24 kS·m(-1) and tensile strengths over 10 MPa, these tapes exhibit the best combination of properties with respect to density heretofore observed for carbon-based papers, membranes, or films. PMID:21545115

Korkut, Sibel; Roy-Mayhew, Joseph D; Dabbs, Daniel M; Milius, David L; Aksay, Ilhan A

2011-05-10

78

Highly reproducible surface-enhanced Raman scattering-active Au nanostructures prepared by simple electrodeposition: origin of surface-enhanced Raman scattering activity and applications as electrochemical substrates.  

PubMed

The fabrication of effective surface-enhanced Raman scattering (SERS) substrates has been the subject of intensive research because of their useful applications. In this paper, dendritic gold (Au) rod (DAR) structures prepared by simple one-step electrodeposition in a short time were examined as an effective SERS-active substrate. The SERS activity of the DAR surfaces was compared to that of other nanostructured Au surfaces with different morphologies, and its dependence on the structural variation of DAR structures was examined. These comparisonal investigations revealed that highly faceted sharp edge sites present on the DAR surfaces play a critical role in inducing a high SERS activity. The SERS enhancement factor was estimated to be greater than 10(5), and the detection limit of rhodamine 6G at DAR surfaces was 10(-8)M. The DAR surfaces exhibit excellent spot-to-spot and substrate-to-substrate SERS enhancement reproducibility, and their long-term stability is very good. It was also demonstrated that the DAR surfaces can be effectively utilized in electrochemical SERS systems, wherein a reversible SERS behavior was obtained during the cycling to cathodic potential regions. Considering the straightforward preparation of DAR substrates and the clean nature of SERS-active Au surfaces prepared in the absence of additives, we expect that DAR surfaces can be used as cost-effective SERS substrates in analytical and electrochemical applications. PMID:23663665

Choi, Suhee; Ahn, Miri; Kim, Jongwon

2013-04-02

79

Response of high and low antibody producer to Brucella.  

PubMed

Biozzi's high and low lines of antibody producers have been applied to an analysis of murine in vivo responses to Brucella. High responders (H/Ab) are better producers of anti-Brucella antibodies and of Brucella induced interferon than low responders (L/Ab). There is no interstrain difference between H/Ab and L/Ab mice as regards to cutaneous hypersensitivity reactions to melitin. Non-immunized L/Ab mice are more resistant to infection with live Brucella than H/Ab. Immunization with formalin killed Brucella leads to a specific protection of both H/Ab and L/Ab mice but magnifies their inter-strain differences: L/Ab are much better protected by preimmunization than H/Ab. The difference between H/Ab and L/Ab mice is not related to an earlier clearance of intravenously inoculated bacteria from the blood stream but to later events affecting the balance between multiplication and digestion of the injected bacteria in the spleen. The lower resistance of H/Ab mice is not due to negative, facilitating-like, activities of immune antibodies: on the contrary, these are shown to have protective properties. These results are discussed in terms of their contribution to present knowledge on Biozzi's mice and their macrophagic functions, on the relations between interferon synthesis and the immune system, and on the mechanism of natural and post-vaccinal protection toward Brucella. PMID:104653

Cannat, A; Bousquet, C; Serre, A

80

Case studies in reproducibility.  

PubMed

Reproducible research is a concept of providing access to data and software along with published scientific findings. By means of some case studies from different disciplines, we will illustrate reasons why readers should be given the possibility to look at the data and software independently from the authors of the original publication. We report results of a survey comprising 100 papers recently published in Bioinformatics. The main finding is that authors of this journal share a culture of making data available. However, the number of papers where source code for simulation studies or analyzes is available is still rather limited. PMID:21278369

Hothorn, Torsten; Leisch, Friedrich

2011-01-28

81

Laser-Produced and Accelerated High Energy Protons  

NASA Astrophysics Data System (ADS)

Ultra-low emittance, multi-MeV proton beams have recently been produced by the interaction of high-intensity short-pulse lasers with thin metallic foils [1]. The acceleration process proceeds in two steps. First the laser ponderomotively accelerates huge, MA currents of ˜MeV electrons which propagate through the foil and form a dense relativistic electron sheath on the non-irradiated rear surface. This sheath produces an electrostatic field >10^12 V/m that ionizes the surface atoms almost instantaneously, forming a ˜1 nm thick ion layer which, together with the electron sheath, resembles a virtual cathode. The ions are accelerated initially normal to the foil surface, followed by a diverging plasma expansion phase driven by the electron plasma pressure. By structuring the rear surface of the foil, we have succeeded to produce modulations in the transverse phase space of the ions, which resemble fiducial ``beamlets'' within the envelope of the expanding plasma. This allows one to image the initial accelerating sheath, and map the plasma expansion of the beam envelope, to fully reconstruct the transverse phase space. We find that for protons of 10 MeV, the normalized transverse rms emittance is less than 0.004 ? mm.mrad [1], i.e. 100-fold better than typical RF accelerators and at substantially higher ion currents exceeding 10 kA. Recent results will be reported on stripping the electrons while maintaining the low emittance from experiments at the LULI 100 TW laser, and theoretical estimates of the lowest emittance which can be expected based on ion heating mechanisms during the initial sheath formation and ion acceleration processes, will be presented. [1] T.E. Cowan, J. Fuchs, H. Ruhl et al., Phys. Rev. Lett. 92, 204801 (2004).

Cowan, Thomas

2005-04-01

82

High- and low-temperature-stable thermal composition for producing high-pressure, high-velocity gases  

DOEpatents

A high- and low-temperature-stable thermite composition for producing high-pressure and high-velocity gases comprises an oxidizable metal, an oxidizing reagent, and a high-temperature-stable gas-producing additive selected from the group consisting of metal carbides and metal nitrides.

Halcomb, D.L.; Mohler, J.H.

1990-03-29

83

Electrical detection of C-reactive protein using a single free-standing, thermally controlled piezoresistive microcantilever for highly reproducible and accurate measurements.  

PubMed

This study demonstrates a novel method for electrical detection of C-reactive protein (CRP) as a means of identifying an infection in the body, or as a cardiovascular disease risk assay. The method uses a single free-standing, thermally controlled piezoresistive microcantilever biosensor. In a commonly used sensing arrangement of conventional dual cantilevers in the Wheatstone bridge circuit, reference and gold-coated sensing cantilevers that inherently have heterogeneous surface materials and different multilayer structures may yield independent responses to the liquid environmental changes of chemical substances, flow field and temperature, leading to unwanted signal disturbance for biosensing targets. In this study, the single free-standing microcantilever for biosensing applications is employed to resolve the dual-beam problem of individual responses in chemical solutions and, in a thermally controlled system, to maintain its sensor performance due to the sensitive temperature effect. With this type of single temperature-controlled microcantilever sensor, the electrical detection of various CRP concentrations from 1 µg/mL to 200 µg/mL was performed, which covers the clinically relevant range. Induced surface stresses were measured at between 0.25 N/m and 3.4 N/m with high reproducibility. Moreover, the binding affinity (KD) of CRP and anti-CRP interaction was found to be 18.83 ± 2.99 µg/mL, which agreed with results in previous reported studies. This biosensing technique thus proves valuable in detecting inflammation, and in cardiovascular disease risk assays. PMID:23899933

Yen, Yi-Kuang; Lai, Yu-Cheng; Hong, Wei-Ting; Pheanpanitporn, Yotsapoom; Chen, Chuin-Shan; Huang, Long-Sun

2013-07-29

84

Electrical Detection of C-Reactive Protein Using a Single Free-Standing, Thermally Controlled Piezoresistive Microcantilever for Highly Reproducible and Accurate Measurements  

PubMed Central

This study demonstrates a novel method for electrical detection of C-reactive protein (CRP) as a means of identifying an infection in the body, or as a cardiovascular disease risk assay. The method uses a single free-standing, thermally controlled piezoresistive microcantilever biosensor. In a commonly used sensing arrangement of conventional dual cantilevers in the Wheatstone bridge circuit, reference and gold-coated sensing cantilevers that inherently have heterogeneous surface materials and different multilayer structures may yield independent responses to the liquid environmental changes of chemical substances, flow field and temperature, leading to unwanted signal disturbance for biosensing targets. In this study, the single free-standing microcantilever for biosensing applications is employed to resolve the dual-beam problem of individual responses in chemical solutions and, in a thermally controlled system, to maintain its sensor performance due to the sensitive temperature effect. With this type of single temperature-controlled microcantilever sensor, the electrical detection of various CRP concentrations from 1 ?g/mL to 200 ?g/mL was performed, which covers the clinically relevant range. Induced surface stresses were measured at between 0.25 N/m and 3.4 N/m with high reproducibility. Moreover, the binding affinity (KD) of CRP and anti-CRP interaction was found to be 18.83 ± 2.99 ?g/mL, which agreed with results in previous reported studies. This biosensing technique thus proves valuable in detecting inflammation, and in cardiovascular disease risk assays.

Yen, Yi-Kuang; Lai, Yu-Cheng; Hong, Wei-Ting; Pheanpanitporn, Yotsapoom; Chen, Chuin-Shan; Huang, Long-Sun

2013-01-01

85

On the High Metallicity Produced by cSNRs  

NASA Astrophysics Data System (ADS)

3C 400.2 is a supernova remnant (SNR) with a complex morphology consisting of two overlapped shells of different diameters: a large shell at the southeast and a small shell at the northwest. High-resolution radio-continuum observations carried out by Dubner et al. (1994) suggested that this complex morphology could be due to the interaction of two SNRs. However, this view has been challenged by recent studies of the H I distribution around this SNR (Giacani et al. 1998) and by the confrontation of theoretical evolutionary models with the morphology at H alpha of this remnant (Velazquez et al. 2001). These recent results suggest that the double shell structure is produced by a single supernova explosion initially expanding into a dense medium encountering a lower density medium and producing a blowout. In this work we present the results of H alpha Fabry-Perot observations obtained with the PUMA equipment at the 2.1 m telescope of the Observatorio Astronómico Nacional at San Pedro Mártir, B. C., México. The kinematic results obtained can allow us to distinguish between those possibilities: two supernova explosions or one supernova explosion undergoing a blowout due to a density gradient.

Rodríguez-González, A.; Tenorio-Tagle, G.; Silich, S. A.

2003-01-01

86

Liquefied extract of marine algae for producing bio-ethanol under high pressure and method for producing the same  

US Patent & Trademark Office Database

A high-pressure liquefied extract of marine algae for producing bioethanol and a method of producing the liquid extract from marine algae under high pressure, and a method of producing the bioethanol from the high-pressure liquid extract by fermentation with yeast are disclosed. According to the production method of bioethanol using marine algae, the high-pressure liquefied extract can be obtained in high yield and fermentation time can be also reduced. Consequently, the yield of bioethanol is increased. Furthermore, the method gives economical and environmentally friendly values from natural marine algae.

2010-07-27

87

High brightness electron beam produced by a ferroelectric cathode  

SciTech Connect

We report experimental measurements of a high brightness electron beam produced by a ferroelectric cathode. Up to 36 A of current (10 A/cm[sup 2]) were obtained at a voltage of 22.5 kV. Electron beam emission was obtained with a dc voltage held between the cathode and anode, and a gate pulse of 1--2 kV applied across the sample. The beam normalized emittance was measured at 10 kV to be 5 mm mrad with a normalized beam brightness of 1.2[times]10[sup 11] A/m[sup 2] rad[sup 2]. This value of beam brightness exceeds that of thermionic cathodes. The ferroelectric cathode emission is found to exceed that of a thermionic cathode using the same geometry.

Jiang, B.; Kirkman, G.; Reinhardt, N. (Integrated Applied Physics, Inc., Torrance, California 90503 (United States))

1995-03-06

88

High-Throughput Selection of Retrovirus Producer Cell Lines Leads to Markedly Improved Efficiency of Germ Line-Transmissible Insertions in Zebra Fish  

Microsoft Academic Search

Vesicular stomatitis virus glycoprotein G-pseudotyped mouse retroviral vectors have been used as mutagens for a large-scale insertional mutagenesis screen in the zebra fish. To reproducibly generate high-titer virus stocks, we devised a method for rapidly selecting cell lines that can yield high-titer viruses and isolated a producer cell line that yields virus at a high titer on zebra fish embryos.

Wenbiao Chen; Shawn Burgess; Greg Golling; Adam Amsterdam; Nancy Hopkins

2002-01-01

89

Reproducing in cities.  

PubMed

Reproducing in cities has always been costly, leading to lower fertility (that is, lower birth rates) in urban than in rural areas. Historically, although cities provided job opportunities, initially residents incurred the penalty of higher infant mortality, but as mortality rates fell at the end of the 19th century, European birth rates began to plummet. Fertility decline in Africa only started recently and has been dramatic in some cities. Here it is argued that both historical and evolutionary demographers are interpreting fertility declines across the globe in terms of the relative costs of child rearing, which increase to allow children to outcompete their peers. Now largely free from the fear of early death, postindustrial societies may create an environment that generates runaway parental investment, which will continue to drive fertility ever lower. PMID:18258904

Mace, Ruth

2008-02-01

90

Morpho-blue reproduced by nanocasting lithography  

NASA Astrophysics Data System (ADS)

The brilliant metallic blue in wings of Morpho butterflies has a mysterious feature. The blue luster is produced from the butterfly's scale, which does not contain a blue pigment at all. The origin of the coloration is then attributed to a microscopic structure that can also explain its high reflectivity. However, its optical characteristics on the scattered wavelength contradicts obviously the grating or multilayer, because it appears blue from wide angle. The mystery of the lack of multi-coloration has recently been explained using a model with a peculiar optical structure, and experimentally proven by fabricating the optical film by controlling the parameters in nanoscale. The reproduced Morpho-blue was found to be important from viewpoint of a wide variety of applications. However, the fabrication process of the nano- structure is too costly due to conventional lithography method. To solve the problem, nano-casting lithography (NCL) was newly applied using UV curable polymer to replicate the nanostructure and improve heat-resistance for the following process of deposition. After fabrication of the nano-patterned polymer structure by the NCL, TiO2 and SiO2 layers were deposited and the Morpho-blue structure was successfully replicated in low cost. The reflective characteristic of the replicated structure was found to reproduce the basic properties of the natural Morpho-blue, as well as the originally fabricated Morpho-blue.

Saito, Akira; Nakajima, Masaki; Miyamura, Yusuke; Sogo, Kenji; Ishikawa, Yoko; Hirai, Yoshihiko

2006-09-01

91

Immuno-MS based targeted proteomics: highly specific, sensitive, and reproducible human chorionic gonadotropin determination for clinical diagnostics and doping analysis.  

PubMed

The human chorionic gonadotropin (hCG) proteins constitute a diverse group of molecules that displays biomarker value in pregnancy detection and cancer diagnostics, as well as in doping analysis. For the quantification of hCG? and qualitative differentiation between other hCG variants in a selective, sensitive, and reproducible manner, the targeted proteomics approach based on mass spectrometric (MS) selected reaction monitoring (SRM) detection was exploited. By optimizing immunoaffinity extraction using monoclonal antibodies coated to magnetic beads, access was granted for the MS to the low-abundance target proteins, ensuring proper sensitivity with limits of detection (LODs) of 2 and 5 IU/L, respectively, for urine and serum samples. Validation according to key elements and recommendations defined by the European Medicines Agency in Guideline on Validation of Bioanalytical Methods was performed. For both matrixes this demonstrated good within-day precision results (within 20% for the lowest concentration, and within 15% for the medium and high concentration), good accuracy results (within 15% for all concentrations), and proper linearity, >0.997 for serum and of 0.999 for urine, in the concentration range up to 5000 IU/L. The method's application in clinical diagnostics was tested on samples from a pregnant woman and from patients previously diagnosed with testicular cancer. For doping analysis, samples from one man having received injection of the hCG-containing pharmaceutical Pregnyl were analyzed. The method proved to be quantitatively accurate with indisputable identification specificity, reducing risks of false positive and false negative results. The successfully validated method advocates thus for more extended use of MS in routine analysis. PMID:22894612

Lund, Hanne; Løvsletten, Karoline; Paus, Elisabeth; Halvorsen, Trine Grønhaug; Reubsaet, Léon

2012-08-30

92

High Energy, High Brightness X-rays Produced by Compton Backscattering at the Livermore Pleiades Facility.  

National Technical Information Service (NTIS)

PLEIADES (Picosecond Laser Electron Interaction for the Dynamic Evaluation of Structures) produces tunable 30-140 keV x-rays with 0.3-5 ps pulse lengths and up to 10(sup 7) photons/pulse by colliding a high brightness electron beam with a high power laser...

A. M. Tremaine S. G. Anderson S. Betts J. Crane D. J. Gibson F. V. Hartemann J. S. Jacob P. Frigola J. Lim J. Rosenzweig G. Travish

2005-01-01

93

Diagnostics of Shiva Nova Produced High Yield Thermonuclear Events.  

National Technical Information Service (NTIS)

Experiments with the Shiva Nova laser facility which produce yield levels of scientific breakeven and above will result in neutron, x-ray and particle fluxes which will require specific attention to the survivability of diagnostic instrumentation. These y...

H. G. Ahlstrom D. L. Banner M. J. Boyle E. M. Campbell L. W. Coleman

1978-01-01

94

Method for producing high surface area chromia materials for catalysis  

Microsoft Academic Search

Nanostructured chromium(III)-oxide-based materials using sol-gel processing and a synthetic route for producing such materials are disclosed herein. Monolithic aerogels and xerogels having surface areas between 150 m.sup.2\\/g and 520 m.sup.2\\/g have been produced. The synthetic method employs the use of stable and inexpensive hydrated-chromium(III) inorganic salts and common solvents such as water, ethanol, methanol, 1-propanol, t-butanol, 2-ethoxy ethanol, and ethylene

Alexander E. Gash; Joe Satcher; Thomas Tillotson; Lawrence Hrubesh; Randall Simpson

2007-01-01

95

Producing high-grade nickel sulfate with solvent displacement crystallization  

Microsoft Academic Search

Solvent displacement crystallization entails the addition of water-miscible organic solvents to aqueous metalliferous solutions to cause salt crystallization. In this work, isopropanol is used to produce well-grown and relatively pure nickel-sulfate hexahydrate crystals from industrial de-copperized electrolyte. By proper selection of the organic-to-aqueous ratio, the method of solvent addition and seeding\\/product recycling, nickel-sulfate crystals were produced with at least an

Georgiana A. Moldoveanu; George P. Demopoulos

2002-01-01

96

Optimal seeding of self-reproducing systems.  

PubMed

This article is motivated by the need to minimize the number of elements required to establish a self-reproducing system. One such system is a self-reproducing extraterrestrial robotic colony, which reduces the launch payload mass for space exploration compared to current mission configurations. In this work, self-reproduction is achieved by the actions of a robot on available resources. An important consideration for the establishment of any self-reproducing system is the identification of a seed, for instance, a set of resources and a set of robots that utilize them to produce all of the robots in the colony. This article outlines a novel algorithm to determine an optimal seed for self-reproducing systems, with application to a self-reproducing extraterrestrial robotic colony. Optimality is understood as the minimization of a cost function of the resources and, in this article, the robots. Since artificial self-reproduction is currently an open problem, the algorithm is illustrated with a simple robotic self-replicating system from the literature and with a more complicated self-reproducing example from nature. PMID:22035080

Menezes, Amor A; Kabamba, Pierre T

2011-10-28

97

Producing high-grade nickel sulfate with solvent displacement crystallization  

Microsoft Academic Search

Solvent displacement crystallization entails the addition of water-miscible organic solvents to aqueous metalliferous solutions\\u000a to cause salt crystallization. In this work, isopropanol is used to produce well-grown and relatively pure nickel-sulfate\\u000a hexahydrate crystals from industrial de-copperized electrolyte. By proper selection of the organic-to-aqueous ratio, the method\\u000a of solvent addition and seeding\\/product recycling, nickel-sulfate crystals were produced with at least an

Georgiana A. Moldoveanu; George P. Demopoulos

2002-01-01

98

Identification of avermectin-high-producing strains by high-throughput screening methods  

Microsoft Academic Search

Avermectins produced by Streptomyces avermitilis are potent against a broad spectrum of nematode and arthropod parasites with low-level side effects on the host organisms.\\u000a This study was designed to investigate a high-throughput screening strategy for the efficient identification of avermectin\\u000a high-yield strains. The production protocol was miniaturized in 96 deep-well microplates. UV absorbance at 245 nm was used\\u000a to monitor avermectin

Hong Gao; Mei Liu; Xianlong Zhou; Jintao Liu; Ying Zhuo; Zhongxuan Gou; Bing Xu; Wenquan Zhang; Xiangyang Liu; Aiqun Luo; Chuansen Zheng; Xiaoping Chen; Lixin Zhang

2010-01-01

99

FORMATION OF COSMIC CRYSTALS IN HIGHLY SUPERSATURATED SILICATE VAPOR PRODUCED BY PLANETESIMAL BOW SHOCKS  

SciTech Connect

Several lines of evidence suggest that fine silicate crystals observed in primitive meteorite and interplanetary dust particles (IDPs) nucleated in a supersaturated silicate vapor followed by crystalline growth. We investigated evaporation of {mu}m-sized silicate particles heated by a bow shock produced by a planetesimal orbiting in the gas in the early solar nebula and condensation of crystalline silicate from the vapor thus produced. Our numerical simulation of shock-wave heating showed that these {mu}m-sized particles evaporate almost completely when the bow shock is strong enough to cause melting of chondrule precursor dust particles. We found that the silicate vapor cools very rapidly with expansion into the ambient unshocked nebular region; for instance, the cooling rate is estimated to be as high as 2000 K s{sup -1} for a vapor heated by a bow shock associated with a planetesimal of radius 1 km. The rapid cooling of the vapor leads to nonequilibrium gas-phase condensation of dust at temperatures much lower than those expected from the equilibrium condensation. It was found that the condensation temperatures are lower by a few hundred K or more than the equilibrium temperatures. This explains the results of the recent experimental studies of condensation from a silicate vapor that condensation in such large supercooling reproduces morphologies similar to those of silicate crystals found in meteorites. Our results strongly suggest that the planetesimal bow shock is one of the plausible sites for formation of not only chondrules but also other cosmic crystals in the early solar system.

Miura, H.; Yamada, J.; Tsukamoto, K.; Nozawa, J. [Department of Earth Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578 (Japan); Tanaka, K. K.; Yamamoto, T. [Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819 (Japan); Nakamoto, T., E-mail: miurah@m.tohoku.ac.j [Earth and Planetary Sciences, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan)

2010-08-10

100

Molecular Crowding of Collagen: A Pathway to Produce Highly-Organized Collagenous Structures  

PubMed Central

Collagen in vertebrate animals is often arranged in alternating lamellae or in bundles of aligned fibrils which are designed to withstand in vivo mechanical loads. The formation of these organized structures is thought to result from a complex, large-area integration of individual cell motion and locally-controlled synthesis of fibrillar arrays via cell-surface fibripositors (direct matrix printing). The difficulty of reproducing such a process in vitro has prevented tissue engineers from constructing clinically useful load-bearing connective tissue directly from collagen. However, we and others have taken the view that long-range organizational information is potentially encoded into the structure of the collagen molecule itself, allowing the control of fibril organization to extend far from cell (or bounding) surfaces. We here demonstrate a simple, fast, cell-free method capable of producing highly-organized, anistropic collagen fibrillar lamellae de novo which persist over relatively long-distances (tens to hundreds of microns). Our approach to nanoscale organizational control takes advantage of the intrinsic physiochemical properties of collagen molecules by inducing collagen association through molecular crowding and geometric confinement. To mimic biological tissues which comprise planar, aligned collagen lamellae (e.g. cornea, lamellar bone or annulus fibrosus), type I collagen was confined to a thin, planar geometry, concentrated through molecular crowding and polymerized. The resulting fibrillar lamellae show a striking resemblance to native load-bearing lamellae in that the fibrils are small, generally aligned in the plane of the confining space and change direction en masse throughout the thickness of the construct. The process of organizational control is consistent with embryonic development where the bounded planar cell sheets produced by fibroblasts suggest a similar confinement/concentration strategy. Such a simple approach to nanoscale organizational control of structure not only makes de novo tissue engineering a possibility, but also suggests a clearer pathway to organization for fibroblasts than direct matrix printing.

Saeidi, Nima; Karmelek, Kathryn N.; Paten, Jeffrey. A; Zareian, Ramin; DiMasi, Elaine

2013-01-01

101

Molecular crowding of collagen: a pathway to produce highly-organized collagenous structures.  

PubMed

Collagen in vertebrate animals is often arranged in alternating lamellae or in bundles of aligned fibrils which are designed to withstand in vivo mechanical loads. The formation of these organized structures is thought to result from a complex, large-area integration of individual cell motion and locally-controlled synthesis of fibrillar arrays via cell-surface fibripositors (direct matrix printing). The difficulty of reproducing such a process in vitro has prevented tissue engineers from constructing clinically useful load-bearing connective tissue directly from collagen. However, we and others have taken the view that long-range organizational information is potentially encoded into the structure of the collagen molecule itself, allowing the control of fibril organization to extend far from cell (or bounding) surfaces. We here demonstrate a simple, fast, cell-free method capable of producing highly-organized, anistropic collagen fibrillar lamellae de novo which persist over relatively long-distances (tens to hundreds of microns). Our approach to nanoscale organizational control takes advantage of the intrinsic physiochemical properties of collagen molecules by inducing collagen association through molecular crowding and geometric confinement. To mimic biological tissues which comprise planar, aligned collagen lamellae (e.g. cornea, lamellar bone or annulus fibrosus), type I collagen was confined to a thin, planar geometry, concentrated through molecular crowding and polymerized. The resulting fibrillar lamellae show a striking resemblance to native load-bearing lamellae in that the fibrils are small, generally aligned in the plane of the confining space and change direction en masse throughout the thickness of the construct. The process of organizational control is consistent with embryonic development where the bounded planar cell sheets produced by fibroblasts suggest a similar confinement/concentration strategy. Such a simple approach to nanoscale organizational control of structure not only makes de novo tissue engineering a possibility, but also suggests a clearer pathway to organization for fibroblasts than direct matrix printing. PMID:22846420

Saeidi, Nima; Karmelek, Kathryn P; Paten, Jeffrey A; Zareian, Ramin; DiMasi, Elaine; Ruberti, Jeffrey W

2012-07-29

102

Producibility of brazed high-dimension centrifugal compressor impellers  

Microsoft Academic Search

The centrifugal compressor impeller is a high technology machine part and its manufacture is a demanding process. The paper shows that it is possible to join high-dimensional impellers parts by brazing. Various aspects of the construction and the brazing process of high-dimensional impellers have been considered and some modifications of the brazing have been proposed. The method was applied in

J Nowacki; P ?wider

2003-01-01

103

High capacity adsorption media and method of producing  

DOEpatents

A method of producing an adsorption medium to remove at least one constituent from a feed stream. The method comprises dissolving at least one metal compound in a solvent to form a metal solution, dissolving polyacrylonitrile into the metal solution to form a PAN-metal solution, and depositing the PAN-metal solution into a quenching bath to produce the adsorption medium. The at least one constituent, such as arsenic, selenium, or antimony, is removed from the feed stream by passing the feed stream through the adsorption medium. An adsorption medium having an increased metal loading and increased capacity for arresting the at least one constituent to be removed is also disclosed. The adsorption medium includes a polyacrylonitrile matrix and at least one metal hydroxide incorporated into the polyacrylonitrile matrix.

Tranter, Troy J. (Idaho Falls, ID); Herbst, R. Scott (Idaho Falls, ID); Mann, Nicholas R. (Blackfoot, ID); Todd, Terry A. (Aberdeen, ID)

2008-05-06

104

New initiatives for producing high current electron accelerators  

SciTech Connect

New classes of compact electron accelerators able to deliver multi-kiloamperes of pulsed 10-50 MeV electron beams are being studied. One class is based upon rf linac technology with dielectric-filled cavities. For materials with {epsilon}/{epsilon}{sub o}>>1, the greatly increased energy storage permits high current operation. The second type is a high energy injected betatron. Circulating current limits scale as {Beta}{sup 2}{gamma}{sup 3}.

Faehl, R.J.; Keinigs, R.K.; Pogue, E.W.

1996-11-01

105

Characterizing Shrapnel and Debris Produced in High Power Laser Experiments  

SciTech Connect

As large laser facilities increase in beam energy and target size, the propensity to produce shrapnel and debris that may impact target-facing optics lifetimes also increases. We present techniques and results using silica aerogel and thin glass plates to characterize the number, velocity, size, and spatial distribution of shrapnel and mass distribution of debris. We have conducted experiments on the HELEN laser to develop these techniques and provide data to support computer modeling of shrapnel and debris generation. We have begun to measure shrapnel and debris generation on Omega and are evolving plans to make similar measurements on NIF. These techniques appear viable for measuring shrapnel and debris with sufficient resolution to quantify their asymmetric deposition within the target chamber. These passive measurements can confirm improved target designs that reduce target shrapnel and debris effects and therefore aid in extending optics lifetime. Ultimately, these data support the most efficient use of optics in executing experimental campaigns on large laser facilities.

Tobin, M; Andrew, J; Eder, D; Haupt, D; Johannes, A; Brown, B

2003-09-01

106

Process for producing high purity zirconium and hafnium  

SciTech Connect

An improved process is described for producing zirconium or hafnium. The process is of the type wherein a tetrachloride of zirconium or hafnium is reduced by magnesium and the resulting metal is subjected to a distillation treatment. The improvement comprises: introducing magnesium chloride into a combination reduction-distillation vessel. An inner liner with at least one bottom drain opening with the drain opening providing fluid communication between the vessel and the liner. The magnesium chloride is added in a quantity to fill the vessel and the inner liner to a level above the liner bottom drain opening, whereby the magnesium chloride provides a seal which prevents magnesium in the inner liner from flowing out of the inner liner.

Kwon, Y.J.

1987-05-26

107

Properties of high nitrogen steels produced by high pressure gas atomization  

SciTech Connect

The production of metal powder by gas atomization typically combines melting at ambient pressure and atomization through high pressure gas jet nozzles into an atomization chamber, also at ambient pressure. To achieve high nitrogen contents, a series of Fe-Cr-Mn-Ni steels were melted under nitrogen pressures of 150 psi and atomized with nitrogen gas into an atomizing chamber held at 100 psi. A small scale atomizing unit (charge size 300 lbs) was modified to achieve the desired production characteristics. High nitrogen steels produced by high pressure gas atomization exceeded the atmospheric solubility limit of nitrogen by as much as 500% and nitrogen contents between 0.5 to 1.3 wt. pct. was achieved. Three Fe-Cr-Mn-Ni alloys each different nitrogen contents were atomized and consolidated by hot-extrusion. The microstructure and tensile properties were evaluate and correlated to conditions during atomization, extrusion and final nitrogen content.

Dunning, John S.

2000-10-01

108

HIGH ENERGY, HIGH BRIGHTNESS X-RAYS PRODUCED BY COMPTON BACKSCATTERING AT THE LIVERMORE PLEIADES FACILITY  

SciTech Connect

PLEIADES (Picosecond Laser Electron Interaction for the Dynamic Evaluation of Structures) produces tunable 30-140 keV x-rays with 0.3-5 ps pulse lengths and up to 10{sup 7} photons/pulse by colliding a high brightness electron beam with a high power laser. The electron beam is created by an rf photo-injector system, accelerated by a 120 MeV linac, and focused to 20 {micro}m with novel permanent magnet quadrupoles. To produce Compton back scattered x-rays, the electron bunch is overlapped with a Ti:Sapphire laser that delivers 500 mJ, 100 fs, pulses to the interaction point. K-edge radiography at 115 keV on Uranium has verified the angle correlated energy spectrum inherent in Compton scattering and high-energy tunability of the Livermore source. Current upgrades to the facility will allow laser pumping of targets synchronized to the x-ray source enabling dynamic diffraction and time-resolved studies of high Z materials. Near future plans include extending the radiation energies to >400 keV, allowing for nuclear fluorescence studies of materials.

Tremaine, A M; Anderson, S G; Betts, S; Crane, J; Gibson, D J; Hartemann, F V; Jacob, J S; Frigola, P; Lim, J; Rosenzweig, J; Travish, G

2005-05-19

109

High ? produced by NBI in the START spherical tokamak  

NASA Astrophysics Data System (ADS)

The world's first high power auxiliary heating experiments in a tight aspect ratio (or spherical) tokamak have been performed on START at R/a ~1.25, using the 40keV, 0.5MW Neutral Beam Injector loaned by the Oak Ridge National Laboratory. Beam performance is being increased in stages. At present 30keV hydrogen neutrals are injected into hydrogen plasmas, and this provides a combination of higher density and effective heating of both ions and electrons, with no adverse MHD instabilities seen so far. Theoretically, the beta limit diagram (?T vs. I/aB_T) for START is large in comparison to that for a conventional tokamak, because much higher values of normalised plasma current can be achieved whilst retaining q_?(a) sufficiently high for kink stability. For example, calculations show(T.C.Hender et al, Proc.22nd EPS, Bournemouth III) p233 (1995) that in START, ?T = 28% (with ?N = 4.5) should be stable to both low-n kinks and narrow? ballooning modes. The highest ? value achieved to date in START is in shot 30234, with ?_T=8% and central beta ?0 = 48%, maintained for about 2 energy confinement times. Already high, these values are expected to further increase with use of higher beam power and with longer plasma discharges. Electron thermal pressure is measured by a 30-point Thomson scattering diagnostic, ion pressure by measuring the central (thermal) ion temperature by a neutral particle analyser and by charge exchange spectroscopy and assuming the same radial profile as the electrons, with dilution factor of 0.8. The \\underlinetotal plasma pressure, including the fast ion component, is estimated both by equilibrium reconstruction and by kinetic measurement supplemented by calculation of the fast ion population with a Fokker-Planck code. These early results give a convincing demonstration of the effectiveness of beam heating in spherical tokamak plasmas which will be further exploited in START and its successor machine, MAST, which is now under construction at Culham. Acknowledgement This work is presented on behalf of the START and NBI teams. We wish to acknowledge the enthusiasm and practical assistance of ORNL personnel, in particular Martin Peng, Jim Tsai and Dick Colchin. This work is funded by the UK Department of Trade and Industry, Euratom and the US DoE.

Sykes, Alan

1996-11-01

110

Processing strategy for producing highly anisotropic silicon nitride  

SciTech Connect

Silicon nitride with a preferred orientation of large elongated grains was obtained by tape casting of raw powder slurry seeded with rodlike {beta}-Si{sub 3}N{sub 4} particles, followed by a gas pressure sintering under 1 MPa nitrogen pressure. The large elongated grains developed from seeds lay in planes parallel to the casting direction in a two-dimensional distribution. Increased fracture toughness (11.1 MPa {center_dot} m{sup 1/2}) and bending strength (1,100 MPa) were achieved in the direction perpendicular to the grains alignment compared to specimens with a random distribution of elongated grains. Moreover, the specimens exhibited a high Weibull modulus of 46 due to the uniform distribution of large grains.

Hirao, Kiyoshi; Ohashi, Masayoshi; Brito, M.E.; Kanzaki, Shuzo [National Industrial Research Inst. of Nagoya (Japan)

1995-06-01

111

Running a reproducible plasma process  

SciTech Connect

Although plasma processing has become an indispensable part of modern integrated circuit fabrication, and modern plasma processing equipment has become sophisticated, it is still not a simple matter to run a reproducible plasma process.

Chapman, B.; Gray, D.E. (Lucas Laboratories, San Jose, CA 95131 (USA))

1990-02-05

112

WHY DO MOST TROPICAL ANIMALS REPRODUCE SEASONALLY? TESTING HYPOTHESES ON AN AUSTRALIAN SNAKE  

Microsoft Academic Search

Most species reproduce seasonally, even in the tropics where activity occurs year-round. Squamate reptiles provide ideal model organisms to clarify the ultimate (adap- tive) reasons for the restriction of reproduction to specific times of year. Females of almost all temperate-zone reptile species produce their eggs or offspring in the warmest time of the year, thereby synchronizing embryogenesis with high ambient

G. P. Brown; R. Shine

2006-01-01

113

Lentiviral vectors containing an enhancer-less ubiquitously acting chromatin opening element (UCOE) provide highly reproducible and stable transgene expression in hematopoietic cells  

Microsoft Academic Search

Ubiquitously acting chromatin opening elements (UCOEs) consist of methylation- free CpG islands encompassing dual diver- gently transcribed promoters of house- keeping genes that have been shown to confer resistance to transcriptional si- lencing and to produce consistent and stable transgene expression in tissue culture systems. To develop improved strat- egies for hematopoietic cell gene therapy, we have assessed the potential

Fang Zhang; Susannah I. Thornhill; Steven J. Howe; Meera Ulaganathan; Axel Schambach; Joanna Sinclair; Christine Kinnon; H. Bobby Gaspar; Michael Antoniou; Adrian J. Thrasher; R. S. Larson; B. P. Alter; G. M. Baerlocher; S. A. Savage; S. J. Chanock; B. B. Weksler; J. P. Willner; J. A. Peters; N. Giri; P. M. Lansdorp; F. Zhang

2007-01-01

114

Reproducibility of ambulatory blood pressure load.  

PubMed

Twenty-two hypertensive patients were monitored during two separate drug-free occasions with a Del Mar Avionics ambulatory device. Blood pressure loads (percentage of systolic and diastolic readings more than 140 and 90 mmHg, respectively) and mean BP were measured both to determine their reproducibility and to examine how they correlate with each other. The systolic and diastolic mean awake BPs for day 1 and day 2 were 140/93 mmHg and 140/91 mmHg, respectively, and BP loads were 45%/55% and 43%/54%. Moreover, mean BP loads correlated highly (r = 0.93) with mean BP values taken on the same day. Both ambulatory mean SBP and BP load were highly reproducible (r = 0.87 and 0.80, respectively, during the awake hours), and mean DBP and load were fairly reproducible (r = 0.59 and 0.39, respectively, during the awake hours). Clinically, however, both were consistent from day 1 to day 2. Mean and individual standard deviations also were reproducible for both systolic and diastolic pressures and loads. PMID:2096203

Zachariah, P K; Sheps, S G; Bailey, K R; Wiltgen, C M; Moore, A G

1990-12-01

115

High Frequency of c-Met Expression in Gastric Cancers Producing Alpha Fetoprotein  

Microsoft Academic Search

Gastric cancers producing ?-fetoprotein (AFP) have a poor prognosis and a high incidence of liver metastasis. Hepatocyte growth factor (HGF) and its receptor, c-Met, are known to induce mitosis and cell movement and to promote tumor progression. In the present study, c-Met and HGF expression in AFP-producing gastric cancer was compared with those gastric cancers that do not produce AFP.

Hideki Amemiya; Koji Kono; Yoshiyuki Mori; Akihiro Takahashi; Fumiko Ichihara; Hidehiko Iizuka; Takayoshi Sekikawa; Yoshiro Matsumoto

2000-01-01

116

Derivation of High Enterotoxin B-Producing Mutants of Staphylococcus aureus from the Parent Strains  

PubMed Central

Certain pH-sensitive (membrane) mutants of Staphylococcus aureus, strains 14458 and 778, produce significantly more type-B enterotoxin (SEB) than the parent type. Some carbohydrate mutants (car) from these parent strains also are superior to the parent in SEB formation. By isolating car mutants from high-SEB-producing membrane mutants, it is possible to derive a double mutant producing from six to 50 times as much SEB as the parent type. Inversion of the sequence by isolating pH-sensitive mutants from car mutants does not yield clones with strikingly higher SEB production than the parent strain. The successful isolation sequence (pH-sensitive mutant first and car mutants derived from it) is relatively simple and virtually assures detection of a truly high-SEB-producing clone. The total number of clones whose direct assay for SEB formation is necessary for detection of a high-producing mutant is on the order of 50 to 60.

Altenbern, Robert A.

1975-01-01

117

GENERATOR FOR PRODUCING HIGH CONCENTRATIONS OF SMALL IONS. Technical Report No. 12  

Microsoft Academic Search

A free ion generator, capable of producing high concentrations of light ; ions with high efficiency, has been developed. lons generated in the corona about ; a needle point are forced through a sonic orifice and thence free of the ; accelerating field. Positive and negative ion concentrations as high as 10\\/sup ; 11\\/ ions\\/cm³ in the sonic jet are

K. T. Whitby; A. R. McFarland; D. A. Lundgren

1960-01-01

118

Time-Resolved Analysis of High-Power-Laser Produced Plasma Expansion in Vacuum.  

National Technical Information Service (NTIS)

Here we consider the results of an experimental investigation of the temporal evolution of plasmas produced by high power laser irradiation of various types of target materials. The experiment was performed at the LULI Laboratory (Ecole Polytechnique, Par...

A. Aliverdiev D. Batani V. Malka T. Vinci M. Koenig

2005-01-01

119

Quantizations from reproducing kernel spaces  

NASA Astrophysics Data System (ADS)

The purpose of this work is to explore the existence and properties of reproducing kernel Hilbert subspaces of L2(C,d2z/?) based on subsets of complex Hermite polynomials. The resulting coherent states (CS) form a family depending on a nonnegative parameter s. We examine some interesting issues, mainly related to CS quantization, like the existence of the usual harmonic oscillator spectrum despite the absence of canonical commutation rules. The question of mathematical and physical equivalences between the s-dependent quantizations is also considered.

Twareque Ali, S.; Bagarello, F.; Pierre Gazeau, Jean

2012-05-01

120

Reproducibility along a 10 cm vertical visual analogue scale  

Microsoft Academic Search

Reproducibility along a vertical 10 cm visual analogue scale (VAS) was investigated. Eight normal volunteers attempted to duplicate a set of marked VAS. There was a tendency to estimate too high on the scale, and reproducibility was found to be variable along its length. This indicates that the error involved in the use of VASs is even more complex than

J S Dixon; H A Bird

1981-01-01

121

Development of molecular-based methods for determination of high histamine producing bacteria in fish.  

PubMed

Histamine (or scombroid) fish poisoning is a significant cause of food borne disease in the United States. In this study, we describe the development of a molecular-based technique which uses digoxigenin (DIG) labeled DNA probes for the detection of gram negative bacteria producing high amounts of histamine (>1000 ppm). A cocktail of PCR amplification fragments corresponding to a 709 bp fragment of the histidine decarboxylase (hdc) gene of four high producing bacteria (Morganella morganii, Enterobacter aerogenes, Raoultella planticola and Photobacterium damselae) was DIG-labeled and screened against a strain bank of 152 gram negative bacteria isolated from scrombroid fish and their harvest environment. The probe cocktail reacted specifically (100%) with the high histamine producing strains but failed to react with low histamine producers and non-producers. To further evaluate the feasibility of the approach, fish homogenate inoculated with known concentrations of four high histamine producing bacterial strains was plated on modified Niven's medium (culture method) and trypticase soy agar supplemented with 2% NaCl (for colony lift hybridization). The colony lift hybridization counts did not differ significantly from the level of the initial inoculum (p>0.05), while the modified Niven's counts were significantly lower (p<0.05) than either inoculum or colony lift counts. The use of digoxigenin (DIG) labeled DNA probes with colony lift hybridization shows promise for accurate and specific enumeration of histamine producing bacteria in scombroid fish. PMID:20392504

Björnsdóttir-Butler, Kristin; Bolton, Gregory E; Jaykus, Lee-Ann; McClellan-Green, Patricia D; Green, David P

2010-03-19

122

Reproducibility of serum cytokines and growth factors  

PubMed Central

Background In most studies, circulating biomarkers are usually assessed from a single sample, assuming that this single measurement represents the long-term biomarker status of the individual. Such an assumption is rarely tested although it may not be valid for all biomarkers. The objective of this study was to investigate the temporal reproducibility of a panel of cytokines and growth factors. Methods Thirty-five postmenopausal women with two annual visits and 30 premenopausal women with three annual visits were randomly selected from the participants in an existing prospective cohort. A total of 23 serum cytokines, nine growth factors and C-reactive protein (CRP) were measured using the Luminex xMap™ technology. In addition, for eight biomarkers, regular and high sensitivity (hs) assays were compared. Results The biomarkers with adequate (>60%) detection rates and acceptable (?0.55) intra-class correlation coefficients (ICCs) were: hsIL-1?, IL-1RA, hsIL-2, hsIL-4, hsIL-5, hsIL-6, hsIL-10, IL-12p40, hsIL-12p70, hsTNF-?, TNF-R1, TNF-R2, CRP, HGF, NGF, and EGFR. The remaining biomarkers either had low temporal reproducibility or were undetectable in more than 40% of samples. Conclusions The results suggest that 16 of the 41 biomarkers measured with Luminex technology showed sufficient sensitivity and temporal reproducibility in sera.

Gu, Yian; Zeleniuch-Jacquotte, Anne; Linkov, Faina; Koenig, Karen L.; Liu, Mengling; Velikokhatnaya, Lyudmila; Shore, Roy E.; Marrangoni, Adele; Toniolo, Paolo; Lokshin, Anna E.; Arslan, Alan A.

2010-01-01

123

Observable and reproducible rogue waves  

NASA Astrophysics Data System (ADS)

In physical regimes described by the cubic, focusing, nonlinear Schrödinger (NLS) equation, the N-dimensional homoclinic orbits of a constant amplitude wave with N unstable modes appear to be good candidates for experimentally observable and reproducible rogue waves. These homoclinic solutions include the Akhmediev breathers (N = 1), which are among the most widely adopted spatially periodic models of rogue waves, and their multi-mode generalizations (N > 1), and will be referred to as multi-mode breathers. Numerical simulations and a linear stability analysis indicate that the breathers with a maximal number of modes (maximal breathers) are robust with respect to rather general perturbations of the initial data in a neighborhood of the unstable background. ).

Calini, A.; Schober, C. M.

2013-10-01

124

Evaluation of guidewire path reproducibility  

PubMed Central

The number of minimally invasive vascular interventions is increasing. In these interventions, a variety of devices are directed to and placed at the site of intervention. The device used in almost all of these interventions is the guidewire, acting as a monorail for all devices which are delivered to the intervention site. However, even with the guidewire in place, clinicians still experience difficulties during the interventions. As a first step toward understanding these difficulties and facilitating guidewire and device guidance, we have investigated the reproducibility of the final paths of the guidewire in vessel phantom models on different factors: user, materials and geometry. Three vessel phantoms (vessel diameters ?4 mm) were constructed having tortuousity similar to the internal carotid artery from silicon tubing and encased in Sylgard elastomer. Several trained users repeatedly passed two guidewires of different flexibility through the phantoms under pulsatile flow conditions. After the guidewire had been placed, rotational c-arm image sequences were acquired (9 in. II mode, 0.185 mm pixel size), and the phantom and guidewire were reconstructed (5123, 0.288 mm voxel size). The reconstructed volumes were aligned. The centerlines of the guidewire and the phantom vessel were then determined using region-growing techniques. Guidewire paths appear similar across users but not across materials. The average root mean square difference of the repeated placement was 0.17±0.02 mm (plastic-coated guidewire), 0.73±0.55 mm (steel guidewire) and 1.15±0.65 mm (steel versus plastic-coated). For a given guidewire, these results indicate that the guidewire path is relatively reproducible in shape and position.

Schafer, Sebastian; Hoffmann, Kenneth R.; Noel, Peter B.; Ionita, Ciprian N.; Dmochowski, Jacek

2008-01-01

125

Evaluation of guidewire path reproducibility.  

PubMed

The number of minimally invasive vascular interventions is increasing. In these interventions, a variety of devices are directed to and placed at the site of intervention. The device used in almost all of these interventions is the guidewire, acting as a monorail for all devices which are delivered to the intervention site. However, even with the guidewire in place, clinicians still experience difficulties during the interventions. As a first step toward understanding these difficulties and facilitating guidewire and device guidance, we have investigated the reproducibility of the final paths of the guidewire in vessel phantom models on different factors: user, materials and geometry. Three vessel phantoms (vessel diameters approximately 4 mm) were constructed having tortuousity similar to the internal carotid artery from silicon tubing and encased in Sylgard elastomer. Several trained users repeatedly passed two guidewires of different flexibility through the phantoms under pulsatile flow conditions. After the guidewire had been placed, rotational c-arm image sequences were acquired (9 in. II mode, 0.185 mm pixel size), and the phantom and guidewire were reconstructed (512(3), 0.288 mm voxel size). The reconstructed volumes were aligned. The centerlines of the guidewire and the phantom vessel were then determined using region-growing techniques. Guidewire paths appear similar across users but not across materials. The average root mean square difference of the repeated placement was 0.17 +/- 0.02 mm (plastic-coated guidewire), 0.73 +/- 0.55 mm (steel guidewire) and 1.15 +/- 0.65 mm (steel versus plastic-coated). For a given guidewire, these results indicate that the guidewire path is relatively reproducible in shape and position. PMID:18561663

Schafer, Sebastian; Hoffmann, Kenneth R; Noël, Peter B; Ionita, Ciprian N; Dmochowski, Jacek

2008-05-01

126

Some new schemes for producing high-accuracy elliptical X-ray mirrors by elastic bending  

SciTech Connect

Although x-ray micro-foci can be produced by a variety of diffractive methods, grazing incidence mirrors are the only route to an achromatic focus. In this paper we describe our efforts to produce elliptically shaped mirrors with the very high figure accuracy necessary for producing a micro-focus. The motivation for this work is provided by the need to produce achromatic foci for a range of applications ranging from tunable micro-focus x-ray photoelectron spectroscopy ({mu}-XPS) at soft x-ray energies to micro-focus white beam x-ray diffraction ({mu}-XRD) at hard x-ray energies. We describe the methodology of beam bending, a practical example of a system we have produced for {mu}-XRD, and results demonstrating the production of a surface with micro-radian figure accuracy.

Padmore, H.A.; Howells, M.R.; Irick, S.; Renner, T.; Sandler, R. [Lawrence Berkeley National Lab., CA (US); Koo, Y.-M. [Pohang Univ. of Science and Technology (Korea, Republic of)

1996-08-01

127

Screening and breeding of high taxol producing fungi by genome shuffling  

Microsoft Academic Search

To apply the fundamental principles of genome shuffling in breeding of taxol-producing fungi, Nodulisporium sylviform was used as starting strain in this work. The procedures of protoplast fusion and genome shuffling were studied. Three hereditarily\\u000a stable strains with high taxol production were obtained by four cycles of genome shuffling. The qualitative and quantitative\\u000a analysis of taxol produced was confirmed using

Kai Zhao; WenXiang Ping; LiNa Zhang; Jun Liu; Yan Lin; Tao Jin; DongPo Zhou

2008-01-01

128

Method for producing high carrier concentration p-Type transparent conducting oxides  

DOEpatents

A method for producing transparent p-type conducting oxide films without co-doping plasma enhancement or high temperature comprising: a) introducing a dialkyl metal at ambient temperature and a saturated pressure in a carrier gas into a low pressure deposition chamber, and b) introducing NO alone or with an oxidizer into the chamber under an environment sufficient to produce a metal-rich condition to enable NO decomposition and atomic nitrogen incorporation into the formed transparent metal conducting oxide.

Li, Xiaonan (Evergreen, CO); Yan, Yanfa (Littleton, CO); Coutts, Timothy J. (Golden, CO); Gessert, Timothy A. (Conifer, CO); Dehart, Clay M. (Westminster, CO)

2009-04-14

129

High-Titer Packaging Cells Producing Recombinant Retroviruses Resistant to Human Serum  

Microsoft Academic Search

Novel retroviral protein expression constructs were designed to retain minimal retroviral sequences and to express dominant selectable markers by reinitiation of translation after expression of the viral genes. HT1080 cells were selected as producer cells for their ability to release high-titer viruses that are resistant to inacti- vation by human serum. Two HT1080-based packaging cell lines which produce Moloney murine

FRANCOIS-LOIC COSSET; YASUHIRO TAKEUCHI; JEAN-LUC BATTINI; ROBIN A. WEISS; ANDMARY K. L. COLLINS

1995-01-01

130

Robust Reproducible Resting State Networks in the Awake Rodent Brain  

PubMed Central

Resting state networks (RSNs) have been studied extensively with functional MRI in humans in health and disease to reflect brain function in the un-stimulated state as well as reveal how the brain is altered with disease. Rodent models of disease have been used comprehensively to understand the biology of the disease as well as in the development of new therapies. RSN reported studies in rodents, however, are few, and most studies are performed with anesthetized rodents that might alter networks and differ from their non-anesthetized state. Acquiring RSN data in the awake rodent avoids the issues of anesthesia effects on brain function. Using high field fMRI we determined RSNs in awake rats using an independent component analysis (ICA) approach, however, ICA analysis can produce a large number of components, some with biological relevance (networks). We further have applied a novel method to determine networks that are robust and reproducible among all the components found with ICA. This analysis indicates that 7 networks are robust and reproducible in the rat and their putative role is discussed.

Becerra, Lino; Pendse, Gautam; Chang, Pei-Ching; Bishop, James; Borsook, David

2011-01-01

131

Insulator coating for high temperature alloys method for producing insulator coating for high temperature alloys  

DOEpatents

A method for fabricating an electrically insulating coating on a surface is disclosed comprising coating the surface with a metal, and reacting the metal coated surface with a nonmetal so as to create a film on the metal-coated surface. Alternatively, the invention provides for a method for producing a noncorrosive, electrically insulating coating on a surface saturated with a nonmetal comprising supplying a molten fluid, dissolving a metal in the molten fluid to create a mixture, and contacting the mixture with the saturated surface. Lastly, the invention provides an electrically insulative coating comprising an underlying structural substrate coated with an oxide or nitride compound

Park, Jong Hee (Clarendon Hills, IL)

1998-01-01

132

Insulator coating for high temperature alloys method for producing insulator coating for high temperature alloys  

DOEpatents

A method for fabricating an electrically insulating coating on a surface is disclosed comprising coating the surface with a metal, and reacting the metal coated surface with a nonmetal so as to create a film on the metal-coated surface. Alternatively, the invention provides for a method for producing a noncorrosive, electrically insulating coating on a surface saturated with a nonmetal comprising supplying a molten fluid, dissolving a metal in the molten fluid to create a mixture, and contacting the mixture with the saturated surface. Lastly, the invention provides an electrically insulative coating comprising an underlying structural substrate coated with an oxide or nitride compound. 2 figs.

Park, J.H.

1998-06-23

133

Toenail selenium as biomarker: reproducibility over a one-year period and factors influencing reproducibility.  

PubMed

We assessed the reproducibility of selenium levels in toenails, comparing concentrations in two sets of specimens collected about a year apart, from 80 women (40 pre-menopausal and 40 post-menopausal) in the period October 1990 to February 1992. The women were participants in a prospective study on hormones and diet in relation to prediagnostic breast cancer (the ORDET study) conducted in northern Italy. Toenail selenium was determined by electrothermal atomic absorption spectrometry. The data were log-transformed as they were not normally distributed. To assess reproducibility Pearson correlation coefficients (r) for the two selenium determinations were calculated in pre- and post-menopausal women, according to smoking status and acetone treatment. A weighted kappa statistic (k) assessed inter-quintile agreement between the two sets of measures. Toenail selenium levels were highly reproducible (r = 0.57, p < 0.001), especially in pre-menopausal women (r = 0.66, p <0.001). Smoking lowered selenium levels (mean difference of 0.24 microg/g, p < 0.05 between smokers and non smokers) but did not significantly influence reproducibility. Acetone treatment to remove nail polish did not modify selenium levels but affected inter-quintile agreement, with moderate agreement (k = 0.58, p < 0.001) when acetone was used at both or neither samplings; and fair non significant agreement (k = 0.39, p = 0.06) when acetone was used at one sampling but not the other. As selenium levels in toenails are highly reproducible, notwithstanding variation in selenium levels in food and long-term changes in individuals' food choices, toenail selenium may be a useful biomarker of selenium exposure, particularly since toenail samples provide a measure of long-term exposure. However age, smoking status and acetone treatment are possible causes of misclassification. PMID:14650626

Krogh, Vittorio; Pala, Valeria; Vinceti, Marco; Berrino, Franco; Ganzi, Angela; Micheli, Andrea; Muti, Paola; Vescovi, Luciano; Ferrari, Angela; Fortini, Katia; Sieri, Sabina; Vivoli, Gianfranco

2003-01-01

134

High strength-high conductivity Cu-Fe composites produced by powder compaction/mechanical reduction  

DOEpatents

A particulate mixture of Cu and Fe is compacted and mechanically reduced to form an ''in-situ'' Cu-Fe composite having high strength and high conductivity. Compaction and mechanical reduction of the particulate mixture are carried out at a temperature and time at temperature selected to avoid dissolution of Fe into the Cu matrix particulates to a harmful extent that substantially degrades the conductivity of the Cu-Fe composite. 5 figures.

Verhoeven, J.D.; Spitzig, W.A.; Gibson, E.D.; Anderson, I.E.

1991-08-27

135

High strength-high conductivity Cu--Fe composites produced by powder compaction/mechanical reduction  

DOEpatents

A particulate mixture of Cu and Fe is compacted and mechanically reduced to form an "in-situ" Cu-Fe composite having high strength and high conductivity. Compaction and mechanical reduction of the particulate mixture are carried out at a temperature and time at temperature selected to avoid dissolution of Fe into the Cu matrix particulates to a harmful extent that substantially degrades the conductivity of the Cu-Fe composite.

Verhoeven, John D. (Ames, IA); Spitzig, William A. (Ames, IA); Gibson, Edwin D. (Ames, IA); Anderson, Iver E. (Ames, IA)

1991-08-27

136

7 CFR 800.166 - Reproducing certificates.  

Code of Federal Regulations, 2013 CFR

...AGRICULTURE GENERAL REGULATIONS Official Certificates § 800.166 Reproducing certificates. Official certificates may be photo copied or similarly reproduced. (Approved by the Office of Management and Budget under control number 0580-0011)...

2013-01-01

137

High-strength, creep-resistant molybdenum alloy and process for producing the same  

DOEpatents

A wet-doping process for producing an oxide-dispersion strengthened (ODS), creep-resistant molybdenum alloy is disclosed. The alloy is made by adding nitrate or acetate salts of lanthanum, cerium, thorium, or yttrium to molybdenum oxide to produce a slurry, heating the slurry in a hydrogen atmosphere to produce a powder, mixing and cold isostatically pressing the powder, sintering in a hydrogen atmosphere, and thermomechanically processing (swaging, extruding, cold drawing) the product. The ODS molybdenum alloy produced by the process contains 2-4% by volume (.about.1-4% by weight) of an oxide of lanthanum, cerium, thorium, or yttrium. The alloy has high strength and improved creep-resistance at temperatures greater than 0.55T.sub.m of molybdenum.

Bianco, Robert (Finleyville, PA); Buckman, Jr., R. William (Pittsburgh, PA); Geller, Clint B. (Pittsburgh, PA)

1999-01-01

138

High-strength, creep-resistant molybdenum alloy and process for producing the same  

DOEpatents

A wet-doping process for producing an oxide-dispersion strengthened (ODS), creep-resistant molybdenum alloy is disclosed. The alloy is made by adding nitrate or acetate salts of lanthanum, cerium, thorium, or yttrium to molybdenum oxide to produce a slurry, heating the slurry in a hydrogen atmosphere to produce a powder, mixing and cold isostatically pressing the powder, sintering in a hydrogen atmosphere, and thermomechanically processing (swaging, extruding, cold drawing) the product. The ODS molybdenum alloy produced by the process contains 2--4% by volume ({approximately}1--4% by weight) of an oxide of lanthanum, cerium, thorium, or yttrium. The alloy has high strength and improved creep-resistance at temperatures greater than 0.55T{sub m} of molybdenum.

Bianco, Robert; Buckman, Jr. William R.; Geller, Clint B.

1997-12-01

139

Generalized multiple scale reproducing kernel particle methods  

Microsoft Academic Search

An approach to unify reproducing kernel methods under one large umbrella and an extension to include time and spatial shifting are proposed. The study is divided into three major topics. The groundwork is set by revisiting the Fourier analysis of discrete systems. The multiresolution concept and its significance in devising the reproducing kernel methods and its discrete counterpart, reproducing kernel

Wing Kam Liu; Yijung Chen; R. Aziz Uras; Chin Tang Chang

1996-01-01

140

Simultaneous suppression of TGF-? and ERK signaling contributes to the highly efficient and reproducible generation of mouse embryonic stem cells from previously considered refractory and non-permissive strains.  

PubMed

Mouse embryonic stem cells (ESCs) are pluripotent stem cell lines derived from pre-implantation embryos. The efficiency of mESC generation is affected by genetic variation in mice; that is, some mouse strains are refractory or non-permissive to ESC establishment. Developing an efficient method to derive mESCs from strains of various genetic backgrounds should be valuable for establishment of ESCs in various mammalian species. In the present study, we identified dual inhibition of TGF-? and ERK1/2, by SB431542 and PD0325901, respectively led to the highly efficient and reproducible generation of mESC lines from NMRI, C57BL/6, BALB/c, DBA/2, and FVB/N strains, which previously considered refractory or non-permissive for ESC establishment. These mESCs expressed pluripotency markers and retained the capacity to differentiate into derivatives of all three germ layers. The evaluated lines exhibited high rates of chimerism when reintroduced into blastocysts. To our knowledge, this is the first report of efficient (100%) mESC lines generation from different genetic backgrounds. The application of these two inhibitors will not only solve the problems of mESC derivation but also clarifies new signaling pathways in pluripotent mESCs. PMID:21814763

Hassani, Seyedeh-Nafiseh; Totonchi, Mehdi; Farrokhi, Ali; Taei, Adeleh; Larijani, Mehran Rezaei; Gourabi, Hamid; Baharvand, Hossein

2012-06-01

141

Coupled-Multiplier Accelerator Produces High-Power Electron Beams for Industrial Applications  

Microsoft Academic Search

The coupled multiplier is a new approach to efficient generation of MeV d.c. power for accelerator applications. High voltage is produced by a series of modules, each of which consists of a high-power alternator, step-up transformer, and 3-phase multiplier circuit. The alternators are connected mechanically along a rotating shaft, and connected by insulating flexible couplers. This approach differs from all

M. Hatridge; P. McIntyre; S. Roberson; A. Sattarov; E. Thomas; Charles Meitzler

2003-01-01

142

High-resolution electron microscopy studies of a microporous carbon produced by arc-evaporation  

Microsoft Academic Search

The soot produced as a byproduct of fullerene synthesis by arc-evaporation consists of a microporous carbon with a surface area, after activation with carbon dioxide, of ca. 700 m2 g-'. Here, we investigate the structure of this material, and its appearance after electron irradiation and high-temperature heat treatment, using high- resolution electron microscopy. We show that the heat treatment transforms

Peter J. F. Harris; Shik Chi Tsang; John B. Claridge; Malcolm L. H. Green

1994-01-01

143

Process for producing synthetic natural gas and high octane motor fuel components  

Microsoft Academic Search

Synthetic natural gas and high octane motor fuel blending stock is produced by catalytically reforming naphtha at low severity to maximize production of aromatics and minimize hydrocracking, and then converting the remaining paraffins to methane in a methanation zone. The effluent from the methanation zone is separated into synthetic natural gas and motor fuel blending stock.

W. C. Pfefferie; W. P. Jr. Hettinger

1978-01-01

144

Removal of As, Cd, Pb, and Zn from contaminated soil by high biomass producing plants  

Microsoft Academic Search

The uptake of As, Cd, Pb, and Zn and potential phytoremediation efficiency of five high biomass producing crops, white sweetclover (Melilotus alba L.), red clover (Trifolium pratense L.), curled mallow (Malva verticillata L.), saf- flower (Carthamus tinctorius L.) and hemp (Cannabis sativa L.) commonly used as grazing and\\/or energy crops was evaluated in both pot and field experiments at soils

P. Tlustoš; J. Száková; J. Hrubý; I. Hartman; J. Najmanová; J. Ned?lník; D. Pavlíková; M. Batysta

2006-01-01

145

Optical Particle Trapping with Higher-order Doughnut Beams Produced Using High Efficiency Computer Generated Holograms  

Microsoft Academic Search

Laser beams containing higher-order phase singularities can be produced with high efficiency computer generated holograms made with very simple equipment. Using such holograms in an optical tweezers experiment we have successfully trapped reflective and absorptive particles in the dark central spot of a focused charge 3 singularity beam. Angular momentum absorbed from the beam can set particles into rotation.

H. He; N. R. Heckenberg; H. Rubinsztein-Dunlop

1995-01-01

146

High performance carbon fibers from mesophases produced by supercritical fluid extraction  

Microsoft Academic Search

The purpose of this research is to investigate the potential of supercritical fluid extraction for the production of an improved precursor for the manufacture of high thermal conductivity carbon fibers. Mesophase pitch fractions were produced by the continuous fractionation of an isotropic petroleum-based pitch with supercritical toluene in a region of liquid-liquid equilibrium. A statistical experimental design was used to

Franck Michel Dauche

1997-01-01

147

Time-Resolved Analysis of High-Power-Laser Produced Plasma Expansion in Vacuum  

SciTech Connect

Here we consider the results of an experimental investigation of the temporal evolution of plasmas produced by high power laser irradiation of various types of target materials. The experiment was performed at the LULI Laboratory (Ecole Polytechnique, Paris). We have developed a method to analyze time-resolved streak-camera images and analyzed a number of results obtained with various materials.

Aliverdiev, A. [Institute of Physics of Daghestan Scientific Center of Russian Academy of the Science, 367003, Russia, Daghestan, Makhachkala, 94 Yaragskogo Street (Russian Federation); Dipartimento di Fisica 'G. Occhialini', Universita degli Studi di Milano, Bicocca (Italy); International Humanitarian and Technical Academy, Russia, Daghestan, Makhachkala, 4 Komarova Street (Russian Federation); Batani, D.; Dezulian, R. [Dipartimento di Fisica 'G. Occhialini', Universita degli Studi di Milano, Bicocca (Italy); Malka, V. [Laboratoire d'Optique Appliquee, UMR CNRS - ENSTA - Ecole Polytechnique, Palaiseau (France); Vinci, T. [Dipartimento di Fisica 'G. Occhialini', Universita degli Studi di Milano, Bicocca (Italy); Laboratore pour l'Utilisation des Lasers Intenses (LULI), UMR, 7605, CNRS CEA -- Universite Paris VI - Ecole Polytechnique, 91128 Palaiseau Cedex (France); Koenig, M.; Benuzzi-Mounaix, A. [Laboratore pour l'Utilisation des Lasers Intenses (LULI), UMR, 7605, CNRS CEA - Universite Paris VI - Ecole Polytechnique, 91128 Palaiseau Cedex (France)

2005-05-16

148

Serological screening for Coxiella burnetii infection and related reproductive performance in high producing dairy cows  

Microsoft Academic Search

The possible relationship between Coxiella-seropositivity and the reproductive performance of cows during the previous year to the serological screening was examined in three high producing dairy herds. The herds had a history of subfertility (18% abortions) and a positive polymerase chain reaction test for Coxiella burnetii in the bulk tank milk with an excretion higher than 104Coxiella \\/ml for all

F. López-Gatius; S. Almeria; I. Garcia-Ispierto

149

Diamond-Like Carbon produced by highly charged ions impact on highly oriented pyrolytic graphite  

Microsoft Academic Search

The formation of Diamond-Like Carbon (DLC) structure on the surface of Highly Oriented Pyrolytic Graphite (HOPG) following Xeq+ (q=5?26) ions irradiation with different fluence is studied with Raman and X-ray photoelectron spectroscopy (XPS) analyses in this work. The DLC structure formed on HOPG is shown by the electronic structure transition from sp2 to sp3 hybridization. An obvious evolution of the

T. S. Wang; J. J. Ding; R. Cheng; H. B. Peng; X. Lu; Y. T. Zhao

150

Moderate Volume of High Relative Training Intensity Produces Greater Strength Gains Compared With Low and High Volumes in Competitive Weightlifters  

Microsoft Academic Search

Gonzalez-Badillo, J.J., M. Izquierdo, and E.M. Gorostiaga. Moderate volume of high relative training in- tensity produces greater strength gains compared with low and high volumes in competitive weightlifters. J. Strength Cond. Res. 20(1)73-81. 2006.—The purpose of this study was to examine the effect of 3 volumes of heavy resistance, average relative training intensity (expressed as a percentage of 1 repetition

Juan José González-Badillo; Mikel Izquierdo; Esteban M. Gorostiaga

2006-01-01

151

High l state population in O sup 7+ produced in ion-solid collisions  

SciTech Connect

The high {ell}-state population of fast ions excited in ion-solid interactions is very different from {ell}-state populations produced under single collision conditions. A study of the population dynamics of electronic excitation and transport within the framework of a classical transport theory for O{sup 2+} (2 MeV/u) ions traversing carbon foils shows food agreement with experimental results from delayed photon emission spectroscopy. We investigate the dependence of the characteristic exponent for the power-law decay of delayed Ly{alpha} and Ly{beta} radiation on the initial n,{ell} distribution. From our simulations we find evidence that the very high {ell}-state populations produced in ion-solid collision are the consequence of a high-{ell} state diffusion under the influence of multiple inelastic and elastic collisions in the bulk of the solid. 15 refs., 4 figs.

Kemmler, J. (Centre Interdisciplinaire de Recherches avec les Ions Lourds, 14 - Caen (France)); Bourgdoerfer, J.; Reinhold, C.O. (Tennessee Univ., Knoxville, TN (United States) Oak Ridge National Lab., TN (United States))

1991-01-01

152

Highly oil-producing microalgae selected through directed-evolution on a microfludic chip  

NASA Astrophysics Data System (ADS)

Some species of photosynthetic microalgae produce signi?cant amounts of oil which can be easily converted to diesel fuel. However, as it stands today, biodiesel is signi?cantly more expensive than fossil fuels. We wish to improve the oil yield and production rate of a single species of microalgae through directed evolution. We propose to utilize our microfabication technology to create microhabitats to control the nutrient environment of the species, monitor oil production through Raman Spectroscopy, and punish colonies of algae which have low oil yield. We believe this process will produce a mutant species with a high oil yield.

Mestler, Troy; Estevez-Torres, Andre; Lambert, Guillaume; Austin, Robert H.

2009-03-01

153

Liquid State Forging: Novel Potentiality to Produce High Performance Components, Process, Plant and Tooling  

NASA Astrophysics Data System (ADS)

The paper deals about a new patented process able to the production of high resistance and high toughness parts, taking into consideration also the tooling need. The molten alloy is introduced into the die cavity at low pressure, then the alloy is forged. The forging action takes place during the alloy solidification process, favouring the reduction of the duration of the process and the production of parts characterised by very high mechanical and ductility properties. The very high mechanical characteristics of the produced parts are obtained thank to their very low porosity content, as well as to their unique microstructure features. Moreover, the process allow the optimisation of the yield of the alloy, in fact the feeding system and the risers are practically absent, this means minimum production of scraps to be recycled. After a short description of the main features of the equipment and of the process, the work take into consideration the aluminium based produced parts, in their as cast state and after T6 heat treatment, comparing their characteristics with those obtainable by the most traditional low pressure and gravity casting processes. In particular, samples for the evaluation of the mechanical properties have been machined from the produced parts to obtain their tensile strength, together with their ductility characteristics. The maximum attained hardness values have also been evaluated. Tensile strength higher than 440 MPa, with elongation up to 18% with hardness higher than 125 HB are easily attainable on Al alloys type A356. Light microscopy observations performed on the transverse section of polished samples and the analysis of the fracture surfaces after mechanical tests allowed to focus the attention on the microstructure details and to highlight the ductile aspects of the fracture to confirm the high quality and high performance of the produced parts.

Rosso, M.; Zago, A.; Claus, P.; Motoiu, P.

2007-04-01

154

Method for producing ceramic composition having low friction coefficient at high operating temperatures  

DOEpatents

A method for producing a stable ceramic composition having a surface with a low friction coefficient and high wear resistance at high operating temperatures. A first deposition of a thin film of a metal ion is made upon the surface of the ceramic composition and then a first ion implantation of at least a portion of the metal ion is made into the near surface region of the composition. The implantation mixes the metal ion and the ceramic composition to form a near surface composite. The near surface composite is then oxidized sufficiently at high oxidizing temperatures to form an oxide gradient layer in the surface of the ceramic composition.

Lankford, Jr., James (San Antonio, TX)

1988-01-01

155

Process for producing gasoline of high octane number, in particular lead-free gasoline  

SciTech Connect

A process is described for producing gasoline of high octane number from C/sub 3/ and C/sub 4/ olefinic cuts, such as those obtained by fractional distillation of a C/sub 3/ / C/sub 4/ catalytic cracking cut. It includes the steps of: (A) oligomerizing propylene of the C/sub 3/ cut to obtain a first gasoline fraction, (B) reacting the isobutene of the C/sub 4/ cut with methanol to produce methyl tert.-butyl ether which is separated from the unreacted C/sub 4/ hydrocarbons to form a second gasoline fraction, (C) alkylating said unreacted C/sub 4/ hydrocarbons with isobutane in the presence of an alkylation catalyst such as hydrofluoric acid, to form a third gasoline fraction, and (D) admixing, at least partially, said first, second and third gasoline fractions, so as to obtain gasoline of high octane number.

Chauvin, Y.; Gaillard, J.; Hellin, M.; Torck, B.; Vu, Q.D.

1981-06-02

156

Injection molding using high-aspect-ratio microstructure mold inserts produced by LIGA technique  

NASA Astrophysics Data System (ADS)

The (mu) SET research group at LSU is developing the three-step LIGA process to inexpensively manufacture high aspect ratio microstructure (HARMs). The first two steps of the process (lithography and electroplating) produce a metallic mold insert that is used as a template for molding microstructure. This paper focuses on injection molding of thermoplastics to produce surfaces covered with HARMs hundreds of micrometers in height, tens of micrometers in width, and separated by gaps on the order of tens of micrometers. Injecting plastic into the narrow, high aspect ratio gaps existing in the HARMs mold inserts (micromolding) offers a set of challenges different from classical injection molding of larger scale parts. This paper provides results of a series of injection molding experiments using a commercially available injection molding machine. Replication of the HARMs was achieved by increasing the injection speed, elevating the tool temperature, and venting the mold cavity. Electron microscopy was used to investigate and assess the molding results.

Despa, Mircea S.; Kelly, Kevin W.; Collier, John R.

1998-09-01

157

Microstructure and magnetic properties of high silicon electrical steel produced by electron beam physical vapor deposition  

Microsoft Academic Search

High silicon electrical steel was produced by electron beam physical vapor deposition. The composition, surface microstructure and cross-section microstructure, phase and preferential orientation of the electrical steel were characterized. The results show that the silicon content of the material is about 6.5wt%. The side of the as-deposited electrical steel close to the substrate is composed of DO3 phase equiaxial grains

X. D. He; X. Li; Y. Sun

2008-01-01

158

Process for producing synthetic natural gas and high octane motor fuel components  

Microsoft Academic Search

Engelhard Minerals and Chemicals Corp.'s process produces both synthetic natural gas and high-octane motor-fuel blending stock by catalytically reforming a naphtha feedstock containing naphthenes of low severity, thereby maximizing production of aromatics and hydrogen by dehydrogenation of naphthenes and minimizing hydrocracking of paraffins. The effluent from the reforming reaction zone is cooled and separated in a first separation zone into

W. C. Pfefferle; W. P. Jr. Hettinger

1978-01-01

159

Methacrylic resin having a high solar radiant energy absorbing property and process for producing the same  

Microsoft Academic Search

A methacrylic resin having a high solar radiant energy absorbing property wherein an organic compound (A) containing cupric ion and a compound (B) having at least one p-o-h bond in a molecule are contained into the methacrylic resin selected from poly(Methyl methacrylate) or methacrylic polymers containing at least 50% by weight of a methyl methacrylate unit. A process for producing

K. Abe; K. Kamada; Y. Nakai

1981-01-01

160

Silver-indium joints produced at low temperature for high temperature devices  

Microsoft Academic Search

A two-step fluxless bonding process adopted to produce high temperature silver-indium joints (80 wt% silver and 20 wt% indium) at relatively low process temperature of 206°C has been developed. After annealing the joint continuously for 26 h at 145°C, its melting temperature increases to 765-780°C, as confirmed by a de-bonding test. The technique thus developed provides a viable alternative to

Ricky W. Chuang; Chin C. Lee

2002-01-01

161

Investigating TLE-Producing High Plains Mesoscale Convective Systems with the NLDN and ELF Transients  

Microsoft Academic Search

During the 2000 STEPS and the 1999 NASA Stratospheric Sprites Balloon campaigns, several remote sensing tools were employed to investigate TLE-producing storms over the High Plains. Low-light video systems deployed at Yucca Ridge documented TLEs (sprites, halos, trolls and gnomes) above a variety of storm systems. A new hybrid ELF\\/VLF technique used receivers in Israel to monitor sprite-related ELF transients

W. A. Lyons; C. Price; S. A. Cummer; E. R. Williams; M. A. Stanley; T. E. Nelson

2001-01-01

162

Aircraft-produced Ice Particles in a Highly Supercooled Altocumulus Cloud  

Microsoft Academic Search

On 25 October during the 1986 Project FIRE Intensive Field Observations experiment, a NCAR King Air mission conducted over a ground-based polarization lidar site at Wausau, Wisconsin, sampled a highly supercooled (28° to 31°C) altocumulus perlucidus layer. Ground-based photography shows the concurrent formation of a contrail, which glaciated and gradually spread until producing an ice crystal optical display. According to

Kenneth Sassen

1991-01-01

163

Characterization of a new Bacillus stearothermophilus isolate: a highly thermostable ?-amylase-producing strain  

Microsoft Academic Search

A novel strain of Bacillus stearothermophilus was isolated from samples of a potato-processing industry. Compared to known a-amylases from other B. stearothermophilus strains, the isolate was found to produce a highly thermostable a-amylase. The half-time of inactivation of this a-amylase was 5.1 h at 80°C and 2.4 h at 90°C. The temperature optimum for activity of the a-amylase was 70°C;

R. D. Wind; R. M. Buitelaar; G. Eggink; H. J. Huizing; L. Dijkhuizen

1994-01-01

164

High-performance liquid chromatography purification of biosurfactant isoforms produced by a marine bacterium  

Microsoft Academic Search

A marine Bacillus strain produced biosurfactant during its growth in a defined glucose-containing medium. An efficient method for separation\\u000a and purification of biosurfactant isoforms was developed and optimized in high-performance liquid chromatography (HPLC) by\\u000a manipulating solvent gradient program and flow rates. Starting with an initial run time of 60 min, the final optimized method\\u000a had a significantly reduced run time of

C. Sivapathasekaran; Soumen Mukherjee; Ramapati Samanta; Ramkrishna Sen

2009-01-01

165

Process for producing high purity isoolefins and dimers thereof by dissociation of ethers  

DOEpatents

Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150 to 250 F at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C[sub 3] to C[sub 6] and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom. 2 figs.

Smith, L.A. Jr.; Jones, E.M. Jr.; Hearn, D.

1984-05-08

166

Interstitial dislocation loop nucleation and growth and swelling produced by high-energy cascades  

SciTech Connect

Structural materials for advanced energy sources such as magnetically-and inertially-confined thermonuclear reactors are subjected to a radiation enviornment that produces high-energy displacement cascades and transmutation products that include helium. We address these characteristics and formulate their effect on the microstructural evolution of a material. We consider that, immediately after a high energy cascade event, a vacancy-rich region exists near the primary event site and that an interstitial-rich zone, formed by collision chains, exists some distance from the primary event site. Transmutation-product helium can diffuse into the vacancy-rich zone and stabilize bubble nuclei that will later grow if sufficient vacancies and helium atoms diffuse to the nucleus. These bubbles are the sinks for excess radiation-produced vacancies. The excess radiation-produced interstitials migrate and bond; if the binding energy is high eneough, a di-interstitial is considered to be a stable dislocation-loop nucleus. The loop nuclei grow if they receive more interstitials than vacancies; this represents material swelling since the bubbles do not cause a lattice contraction to offset the dilation caused by the growing dislocation loops.

Yu, J.; Sommer, W.F.; Bradbury, J.N.

1986-01-01

167

Method for producing shaped parts from high temperature oxide metal superconductive composites  

SciTech Connect

This patent describes a process for producing a superconductor material from high temperature oxide-metal superconductive composites with high mechanical properties. It comprises mixing together the appropriate portions of a superconductive powder, a metal and a compound selected from the group consisting of an oxygen donor, a fluorine donor and mixtures thereof; and sintering under pressure the mixed together portion to thereby form the superconductive element which is macroscopically uniform and which contains from 20 to 90% by volume of the metal, 80 to 10% by volume of the superconductive powder and 1 to 20% by volume of the compound.

Chen, I.G.; Stefanescu, D.M.; Sen, S.; Betts, J.

1992-09-08

168

Radiation forces on a dielectric sphere produced by highly focused hollow Gaussian beams  

NASA Astrophysics Data System (ADS)

The radiation force on a dielectric sphere produced by highly focused hollow Gaussian beams (HGBs) in the Rayleigh scattering regime is theoretically investigated. Numerical results demonstrate that, the highly focused HGB at the focus of the lens system becomes a peak-centered shape which can be used to stably trap and manipulate the particles with the refractive index larger than the ambient, and in the neighborhood of the focus the beam becomes a doughnut shape which can be used to guide the particles with refractive index lower than the ambient. The condition of the trapping stability is also analyzed.

Zhao, Cheng-Liang; Wang, Li-Gang; Lu, Xuan-Hui

2007-04-01

169

Studies of Cardiac Muscle with a High Permeability to Calcium Produced by Treatment with Ethylenediaminetetraacetic Acid  

PubMed Central

Thin strips of frog ventricle were isolated and bathed for 15 min in a solution containing 140 mM KCl, 5 mM Na2ATP, 3 mM EDTA, and 10 mM Tris buffer at pH 7.0. The muscle was then exposed to contracture solutions containing 140 mM KCl, 5 mM Na2ATP, 1 mM MgCl2, 10 mM Tris, 3 mM EGTA, and CaCl2 in amounts to produce concentrations of free calcium from 10-4.8 M to 10-9 M. The muscles developed some tension at approximately 10-8 M, and maximum tension was achieved in 10-5 M Ca++. They relaxed in Ca++ concentrations less than 10-8 M. The development of tension by the EDTA-treated muscles was normalized by comparison with twitch tension at a stimulation rate of 9 per min before exposure to EDTA. In 10-5 M Ca++ tension was always several times the twitch tension and was greater than the contracture tension of a frog ventricular strip in KCl low Na-Ringer. Tension equal to half-maximum was produced at approximately 10-6.2 M Ca++. Intracellular recording of membrane potential indicated that after EDTA treatment the resting potential of cells in Ringer solution with 10-5 M Ca or less was between 5 and 20 mv. Contracture solutions did not produce tension without prior treatment with EDTA. The high permeability of the membrane produced by EDTA was reversed and the normal resting and action potentials restored in 1 mM Ca-Ringer. Similar studies of EDTA-treated rabbit right ventricular papillary muscle produced a similar tension vs. Ca++ concentration relation, and the high permeability state reversed with exposure to normal Krebs solution.

Winegard, Saul

1971-01-01

170

Isolation of Bacillus subtilis (chungkookjang), a poly-gamma-glutamate producer with high genetic competence.  

PubMed

A bacterium with high poly-gamma-glutamate (PGA) productivity was isolated from the traditional Korean seasoning, Chung-Kook-Jang. This bacterium could be classified as a Bacillus subtilis, but sporulation in culture was infrequent in the absence of Mn2+. It was judged to be a variety of B. subtilis and designated B. subtilis (chungkookjang). L-Glutamate significantly induced PGA production, and highly elongated PGAs were synthesized. The volumetric yield reached 13.5 mg ml(-1) in the presence of 2% L-glutamate. The D-glutamate content was over 50% in every PGA produced under the conditions used. During PGA production, glutamate racemase activity was found in the cells, suggesting that the enzyme is involved in the D-glutamate supply. Molecular sizes of PGAs were changed by the salt concentration in the medium; PGAs with comparatively low molecular masses were produced in culture media containing high concentrations of NaCl. B. subtilis (chungkookjang) harbors no plasmid and is the first B. subtilis strain reported with both naturally high PGA productivity and high genetic competence. PMID:11778891

Ashiuchi, M; Kamei, T; Baek, D H; Shin, S Y; Sung, M H; Soda, K; Yagi, T; Misono, H

2001-12-01

171

The solubility of fish-produced high magnesium calcite in seawater  

NASA Astrophysics Data System (ADS)

Fish have been shown to produce high (10 to 48 mol %) magnesium calcite as part of the physiological mechanisms responsible for maintaining salt and water balance. The importance of this source to the marine carbon cycle is only now being considered. In this paper, we report the first measurements of the solubility of this CaCO3 in seawater. The resulting solubility (pK*sp = 5.89 ± 0.09) is approximately two times higher than aragonite and similar to the high magnesium calcite generated on the Bahamas Banks (pK*sp = 5.90). This high solubility of fish-produced CaCO3 is a result of the high magnesium content and not a product of micro-environments created by microbial activity. This material is soluble in near surface waters, contributing to the input of carbonate to surface ocean waters, and may at least partially explain the observed increase in total alkalinity above the aragonite saturation horizon.

Woosley, Ryan J.; Millero, Frank J.; Grosell, Martin

2012-04-01

172

Collisionless shocks in laser-produced plasma generate monoenergetic high-energy proton beams  

NASA Astrophysics Data System (ADS)

Compact and affordable ion accelerators based on laser-produced plasmas have potential applications in many fields of science and medicine. However, the requirement of producing focusable, narrow-energy-spread, energetic beams has proved to be challenging. Here we demonstrate that laser-driven collisionless shocks can accelerate proton beams to ~20MeV with extremely narrow energy spreads of about 1% and low emittances. This is achieved using a linearly polarized train of multiterawatt CO2 laser pulses interacting with a gas-jet target. Computer simulations show that laser-heated electrons launch a collisionless shock that overtakes and reflects the protons in the slowly expanding hydrogen plasma, resulting in a narrow energy spectrum. Simulations predict the production of ~200MeV protons needed for radiotherapy by using current laser technology. These results open a way for developing a compact and versatile, high-repetition-rate ion source for medical and other applications.

Haberberger, Dan; Tochitsky, Sergei; Fiuza, Frederico; Gong, Chao; Fonseca, Ricardo A.; Silva, Luis O.; Mori, Warren B.; Joshi, Chan

2012-01-01

173

Uncovering of High Strontium Content in Biogenic Calcite: New Data From a Murolith- producing Coccolithophore  

NASA Astrophysics Data System (ADS)

Biogeochemical studies of modern coccolithophores have demonstrated a link between growth rate and the incorporation of strontium into coccolith calcite. Values for the Sr content of coccolithophores have been quoted as high as 30 mmol/mol. A paleochemical study of the Early Jurassic deposits of the Paris Basin reveals a biogeochemical anomaly. It appears indeed that a coccolithophorid genus, Crepidolithus, contains unexpected amounts of strontium (ca. 12-20% weight) in their calcite lattice that corresponds to a Sr/Ca ratio around 130 mmol/mol. These results have been obtained using a innovative protocol which enables the concentration of Crepidolithus from a polyspecific assemblage. Chemical measurements have then been performed by ICP-GAAS after a weak acid leaching. SEM spot analyses confirm the reproducibility of high values. At the same time, other calcareous particles (such as Schizosphaerella, coccoliths and euhedral monocrystals) do not show such parallel enrichments in strontium. This observation enables us to preclude diagenesis as the cause of the high Sr values. Moreover, further investigations (SEM, XRD, selective leaching) rule out an additional contaminant phase such as sulfates. Finally, in view of the good preservation of Crepidolithus in the sediment, an aragonite precursor for this coccolith genus can also be excluded. If true, these results raise the question about the mode of incorporation of strontium into the calcite lattice because these values require huge KSr (>> 0.13) and/or unrealistic Sr content in the seawater (ca. 150 ppm !). We discuss here several explanations to explain this bioincorporation of strontium into these coccoliths. 1. A mineralization of (Crepidolithus from a distinct water mass extraordinarily enriched in Sr. For that, we present the physico-chemical structure of the water column during the Early Toarcian OAE and the geographic repartition of this anomaly. 2. A differential vital effect explained by physiological pathways (cross-membrane transport). 3. A kinetic effect due to the growth mode of this murolith where vertical V-units are dominant. In order to verify that last hypothesis, we also investigate the Sr content from others same-structured coccoliths (e.g., Crucirhabdus).

Hermoso, M.; Minoletti, F.; de Rafélis, M.; Rickaby, R.; Hesselbo, S.

2007-12-01

174

High-Power Laser Pulse Recirculation for Inverse Compton Scattering-Produced Gamma-Rays  

SciTech Connect

Inverse Compton scattering of high-power laser pulses on relativistic electron bunches represents an attractive method for high-brightness, quasi-monoenergetic {gamma}-ray production. The efficiency of {gamma}-ray generation via inverse Compton scattering is severely constrained by the small Thomson scattering cross section. Furthermore, repetition rates of high-energy short-pulse lasers are poorly matched with those available from electron accelerators, resulting in low repetition rates for generated {gamma}-rays. Laser recirculation has been proposed as a method to address those limitations, but has been limited to only small pulse energies and peak powers. Here we propose and experimentally demonstrate an alternative method for laser pulse recirculation that is uniquely capable of recirculating short pulses with energies exceeding 1 J. Inverse Compton scattering of recirculated Joule-level laser pulses has a potential to produce unprecedented peak and average {gamma}-ray brightness in the next generation of sources.

Jovanovic, I; Shverdin, M; Gibson, D; Brown, C

2007-04-17

175

A physical activity questionnaire: Reproducibility and validity  

Microsoft Academic Search

This study evaluates the Quantification de L'Activite Physique en Altitude chez les Enfants (QAPACE) supervised self- administered questionnaire reproducibility and validity on the estimation of the mean daily energy expenditure (DEE) on Bogotá's schoolchildren. The comprehension was assessed on 324 students, whereas the reproducibility was studied on a dif- ferent random sample of 162 who were exposed twice to it.

Nicolas Barbosa; Carlos E. Sanchez; Jose A. Vera; Wilson Perez; Jean-Christophe Thalabard; Michel Rieu

2007-01-01

176

Synchronous Objects for One Flat Thing, reproduced  

Microsoft Academic Search

Synchronous Objects for One Flat Thing, reproduced is an interactive screen-based work developed by The Ohio State University's Advanced Computing Center for the Arts and Design and the Department of Dance in collaboration with renowned choreographer William Forsythe. Pivoting on Forsythe's masterwork of visual complexity, One Flat Thing, reproduced (OFTr), the Synchronous Objects project seeks to enrich cross-disciplinary investigation and

Maria Palazzi; Norah Zuniga Shaw; William Forsythe; Matthew Lewis; Beth Albright; Michael Andereck; Sucheta Bhatawadekar; Hyowon Ban; Andrew Calhoun; Jane Drozd; Joshua Fry; Melissa Quintanilha; Anna Reed; Benjamin Schroeder; Lily Skove; Ashley Thorndike; Mary Twohig; Ola Ahlqvist; Peter Chan; Noel Cressie; Stephen Turk; Jill Johnson; Christopher Roman; Elizabeth Waterhouse; Scott deLahunta; Patrick Haggard; Alva Noe

2009-01-01

177

On The Reproducibility of Seasonal Land-surface Climate  

SciTech Connect

The sensitivity of the continental seasonal climate to initial conditions is estimated from an ensemble of decadal simulations of an atmospheric general circulation model with the same specifications of radiative forcings and monthly ocean boundary conditions, but with different initial states of atmosphere and land. As measures of the ''reproducibility'' of continental climate for different initial conditions, spatio-temporal correlations are computed across paired realizations of eleven model land-surface variables in which the seasonal cycle is either included or excluded--the former case being pertinent to climate simulation, and the latter to seasonal anomaly prediction. It is found that the land-surface variables which include the seasonal cycle are impacted only marginally by changes in initial conditions; moreover, their seasonal climatologies exhibit high spatial reproducibility. In contrast, the reproducibility of a seasonal land-surface anomaly is generally low, although it is substantially higher in the Tropics; its spatial reproducibility also markedly fluctuates in tandem with warm and cold phases of the El Nino/Southern Oscillation. However, the overall degree of reproducibility depends strongly on the particular land-surface anomaly considered. It is also shown that the predictability of a land-surface anomaly implied by its reproducibility statistics is consistent with what is inferred from more conventional predictability metrics. Implications of these results for climate model intercomparison projects and for operational forecasts of seasonal continental climate also are elaborated.

Phillips, T J

2004-10-22

178

Development of high-performance ER gel produced by electric-field assisted molding  

NASA Astrophysics Data System (ADS)

Electro-rheological gel (ERG) is a novel functional elastomer whose surface frictional and adhesive property varies according to the intensity of applied electric field. This peculiar phenomenon is named as Electro-adhesive effect. A generated shear stress of ERG under applied electric field is approximately 30~40 times higher than that of ERF because of high adhesive strength. However, the performances of ERG vary widely due to its surface condition, especially density and distribution of ER particles at the surface. In order to stabilize and improve the performance of ERG, the electric- filed assisted molding process is proposed as the producing method of ERG. In this study, first, the principle of electro-adhesive effect is theoretically investigated. Second, a high-performance ERG produced by the proposed process, in which ER particles are aligned densely at the surface, is developed and its performance is evaluated experimentally. As the experimental result, the high-performance ERG shows twice higher shear stress than the conventional ERG.

Kakinuma, Y.; Aoyama, T.; Anzai, H.

2009-02-01

179

Road map for studies to produce consistent and high performance SRF accelerator structures  

NASA Astrophysics Data System (ADS)

Superconducting Radio Frequency (SRF) accelerator structures made from high purity niobium are becoming the technological choice for a large number of future accelerators and energy recovery LINAC's (ERL). Most of the presently planned accelerators and ERL requirements will be met with some effort by the current SRF technology where accelerating gradients of about 20 MV/m can be produced on a routine basis with an acceptable yield. However, the XFEL at DESY and the planned ILC require acceleration gradients more than 28 MV/m and 35 MV/m respectively. At the recent ILC meeting at Snowmass (2005) concern was expressed regarding the wide spread in the achieved accelerator gradients and the relatively low yields. For obtaining accelerating gradients of 35 MV/m in SRF accelerator structures consistently, a deeper understanding of the causes for the spread has to be gained and advances have to be made in many scientific and high technology fields, including materials, surface and vacuum sciences, application of reliable processes and procedures, which provide contamination -free surfaces and avoid recontamination and cryogenics related technologies. In this contribution a road map for studies needed to produce consistent and high performance SRF accelerator structures from the needed materials development to clean and non-recontaminating processes and procedures will be presented.

Myneni, G. R.; O'Hanlon, J. F.

2008-05-01

180

Road Map for Studies to Produce Consistent and High Performance SRF Accelerator Structures  

SciTech Connect

Superconducting Radio Frequency (SRF) accelerator structures made from high purity niobium are becoming the technological choice for a large number of future accelerators and energy recovery LINAC’s (ERL). Most of the presently planned accelerators and ERL requirements will be met with some effort by the current SRF technology where accelerating gradients of about 20 MV/m can be produced on a routine basis with an acceptable yield. However, the XFEL at DESY and the planned ILC require acceleration gradients more than 28 MV/m and 35 MV/m respectively. At the recent ILC meeting at Snowmass (2005) concern was expressed regarding the wide spread in the achieved accelerator gradients and the relatively low yields. For obtaining accelerating gradients of 35 MV/m in SRF accelerator structures consistently, a deeper understanding of the causes for the spread has to be gained and advances have to be made in many scientific and high technology fields, including materials, surface and vacuum sciences, application of reliable processes and procedures, which provide contamination –free surfaces and avoid recontamination and cryogenics related technologies. In this contribution a road map for studies needed to produce consistent and high performance SRF accelerator structures from the needed materials development to clean and non-recontaminating processes and procedures will be presented.

Ganapati Rao Myneni; John F. O’Hanlon

2007-06-20

181

A low-temperature method to produce highly reduced graphene oxide.  

PubMed

Chemical reduction of graphene oxide can be used to produce large quantities of reduced graphene oxide for potential application in electronics, optoelectronics, composite materials and energy-storage devices. Here we report a highly efficient one-pot reduction of graphene oxide using a sodium-ammonia solution as the reducing agent. The solvated electrons in sodium-ammonia solution can effectively facilitate the de-oxygenation of graphene oxide and the restoration of ?-conjugation to produce reduced graphene oxide samples with an oxygen content of 5.6 wt%. Electrical characterization of single reduced graphene oxide flakes demonstrates a high hole mobility of 123 cm(2)?Vs(-1). In addition, we show that the pre-formed graphene oxide thin film can be directly reduced to form reduced graphene oxide film with a combined low sheet resistance (~350 ? per square with ~80% transmittance). Our study demonstrates a new, low-temperature solution processing approach to high-quality graphene materials with lowest sheet resistance and highest carrier mobility. PMID:23443567

Feng, Hongbin; Cheng, Rui; Zhao, Xin; Duan, Xiangfeng; Li, Jinghong

2013-01-01

182

Method for producing low-resistivity electrical contacts for high-temperature superconducting ceramics  

DOEpatents

Production of low-resistivity electrical contacts for high-temperature superconducting ceramics capable of supporting large current densities by plasma spraying of a noble metal powder onto a chosen surface area of the ceramic and electrically contacting a metal conductor to the metallic pad formed thereby by either soldering or by use of a conducting epoxy is described. Surface resistivities in the 10{sup {minus}8} {Omega}-cm{sup 2} range have been measured at 76 K. Most experimental variables were found to have little effect on the properties of the contacts produced. 2 tabs.

Katz, J.D.; Willis, J.O.; Maley, M.P.; Castro, R.G.

1989-08-22

183

High yield bio-butanol production by solvent-producing bacterial microflora.  

PubMed

Highly efficient butanol-producing bacterial microflora were isolated from hydrogen-producing sludge of a sewage treatment plant. Based on denaturing gradient gel electrophoresis (DGGE) analysis and 16s rDNA comparison, four strains from the butanol-producing microflora were identified as Clostridium saccharoperbutylacetonicum, Clostridium butylicum, Clostridium beijernckii, and Clostridium acetobutylicum. The effects of glucose, FeSO(4) · 7H(2)O and yeast extract concentrations on the butanol production by the mixture culture were investigated on batch mode. The medium composition for bio-butanol production was optimized using the Box-Behnken design and response surface methodology (RSM). The maximum butanol production rate (0.25 ± 0.02 g/L-h) and concentration (12.4 g/L) were obtained under the condition of glucose concentration, 60 g/L; FeSO(4) · 7H(2)O, 0.516 g/L; yeast extract concentration, 5.13 g/L. Addition of 6.0 g/L butyric acid significantly increased the butanol titer to 17.51 ± 0.49 g/L. Pressurized fermentation strategy (employed with a 5L fermentor) further enhanced the butanol concentration to 21.35 g/L, along with a maximum butanol rate of 1.25 g/L-h. PMID:22244959

Cheng, Chieh-Lun; Che, Pei-Yi; Chen, Bor-Yann; Lee, Wen-Jhy; Chien, Liang-Jung; Chang, Jo-Shu

2012-01-02

184

High doses of dextromethorphan, an NMDA antagonist, produce effects similar to classic hallucinogens  

PubMed Central

Rationale Although reports of dextromethorphan (DXM) abuse have increased recently, few studies have examined the effects of high doses of DXM. Objective This study in humans evaluated the effects of supratherapeutic doses of DXM and triazolam. Methods Single, acute, oral doses of DXM (100, 200, 300, 400, 500, 600, 700, 800 mg/70 kg), triazolam (0.25, 0.5 mg/70kg), and placebo were administered to twelve healthy volunteers with histories of hallucinogen use, under double-blind conditions, using an ascending dose run-up design. Subjective, behavioral, and physiological effects were assessed repeatedly after drug administration for 6 hours. Results Triazolam produced dose-related increases in subject-rated sedation, observer-rated sedation, and behavioral impairment. DXM produced a profile of dose-related physiological and subjective effects differing from triazolam. DXM effects included increases in blood pressure, heart rate, and emesis, increases in observer-rated effects typical of classic hallucinogens (e.g. distance from reality, visual effects with eyes open and closed, joy, anxiety), and participant ratings of stimulation (e.g. jittery, nervous), somatic effects (e.g. tingling, headache), perceptual changes, end-of-session drug liking, and mystical-type experience. After 400 mg/70kg DXM, 11 of 12 participants indicated on a pharmacological class questionnaire that they thought they had received a classic hallucinogen (e.g. psilocybin). Drug effects resolved without significant adverse effects by the end of the session. In a 1-month follow up volunteers attributed increased spirituality and positive changes in attitudes, moods, and behavior to the session experiences. Conclusions High doses of DXM produced effects distinct from triazolam and had characteristics that were similar to the classic hallucinogen psilocybin.

Carter, Lawrence P.; Johnson, Matthew W.; Mintzer, Miriam Z.; Klinedinst, Margaret A.; Griffiths, Roland R.

2013-01-01

185

Why do most tropical animals reproduce seasonally? Testing hypotheses on an Australian snake.  

PubMed

Most species reproduce seasonally, even in the tropics where activity occurs year-round. Squamate reptiles provide ideal model organisms to clarify the ultimate (adaptive) reasons for the restriction of reproduction to specific times of year. Females of almost all temperate-zone reptile species produce their eggs or offspring in the warmest time of the year, thereby synchronizing embryogenesis with high ambient temperatures. However, although tropical reptiles are freed from this thermal constraint, most do not reproduce year-round. Seasonal reproduction in tropical reptiles might be driven by biotic factors (e.g., peak periods of predation on eggs or hatchlings, or food for hatchlings) or abiotic factors (e.g., seasonal availability of suitably moist incubation conditions). Keelback snakes (Tropidonophis mairii, Colubridae) in tropical Australia reproduce from April to November, but with a major peak in May-June. Our field studies falsify hypotheses that invoke biotic factors as explanations for this pattern: the timing of nesting does not minimize predation on eggs, nor maximize food availability or survival rates for hatchlings. Instead, our data implicate abiotic factors: female keelbacks nest most intensely soon after the cessation of monsoonal rains when soils are moist enough to sustain optimal embryogenesis (wetter nests produce larger hatchlings, that are more likely to survive) but are unlikely to become waterlogged (which is lethal to eggs). Thus, abiotic factors may favor seasonal reproduction in tropical as well as temperate-zone animals. PMID:16634304

Brown, G P; Shine, R

2006-01-01

186

Reproducibility of dynamically represented acoustic lung images from healthy individuals  

PubMed Central

Background and aim: Acoustic lung imaging offers a unique method for visualising the lung. This study was designed to demonstrate reproducibility of acoustic lung images recorded from healthy individuals at different time points and to assess intra- and inter-rater agreement in the assessment of dynamically represented acoustic lung images. Methods: Recordings from 29 healthy volunteers were made on three separate occasions using vibration response imaging. Reproducibility was measured using quantitative, computerised assessment of vibration energy. Dynamically represented acoustic lung images were scored by six blinded raters. Results: Quantitative measurement of acoustic recordings was highly reproducible with an intraclass correlation score of 0.86 (very good agreement). Intraclass correlations for inter-rater agreement and reproducibility were 0.61 (good agreement) and 0.86 (very good agreement), respectively. There was no significant difference found between the six raters at any time point. Raters ranged from 88% to 95% in their ability to identically evaluate the different features of the same image presented to them blinded on two separate occasions. Conclusion: Acoustic lung imaging is reproducible in healthy individuals. Graphic representation of lung images can be interpreted with a high degree of accuracy by the same and by different reviewers.

Maher, T M; Gat, M; Allen, D; Devaraj, A; Wells, A U; Geddes, D M

2008-01-01

187

Reproducibility of regional brain metabolic responses to lorazepam  

SciTech Connect

Changes in regional brain glucose metabolism in response to benzodiazepine agonists have been used as indicators of benzodiazepine-GABA receptor function. The purpose of this study was to assess the reproducibility of these responses. Sixteen healthy right-handed men underwent scanning with PET and [{sup 18}F]fluorodeoxyglucose (FDG) twice: before placebo and before lorazepam (30 {mu}g/kg). The same double FDG procedure was repeated 6-8 wk later on the men to assess test-retest reproducibility. The regional absolute brain metabolic values obtained during the second evaluation were significantly lower than those obtained from the first evaluation regardless of condition (p {le} 0.001). Lorazepam significantly and consistently decreased both whole-brain metabolism and the magnitude. The regional pattern of the changes were comparable for both studies (12.3% {plus_minus} 6.9% and 13.7% {plus_minus} 7.4%). Lorazepam effects were the largest in the thalamus (22.2% {plus_minus} 8.6% and 22.4% {plus_minus} 6.9%) and occipital cortex (19% {plus_minus} 8.9% and 21.8% {plus_minus} 8.9%). Relative metabolic measures were highly reproducible both for pharmacolgic and replication condition. This study measured the test-retest reproducibility in regional brain metabolic responses, and although the global and regional metabolic values were significantly lower for the repeated evaluation, the response to lorazepam was highly reproducible. 1613 refs., 3 figs., 3 tabs.

Wang, G.J.; Volkow, N.D.; Overall, J. [Brookhaven National Lab., Upton, NY (United States)]|[SUNY, Stony Brook, NY (United States)] [and others

1996-10-01

188

High performance carbon fibers from mesophases produced by supercritical fluid extraction  

NASA Astrophysics Data System (ADS)

The purpose of this research is to investigate the potential of supercritical fluid extraction for the production of an improved precursor for the manufacture of high thermal conductivity carbon fibers. Mesophase pitch fractions were produced by the continuous fractionation of an isotropic petroleum-based pitch with supercritical toluene in a region of liquid-liquid equilibrium. A statistical experimental design was used to investigate a region of extraction operating conditions from which the fractions were expected to exhibit superior spinnability. Chemical and physical characterizations were performed on the fractions, and the results were used to explore the effect of the extraction conditions on the mesophase properties. DRIFT data were shown to be particularly useful for characterizing the chemical composition of the mesophase fractions produced, and GPC was successfully used to determine their molecular weight distribution. Two thermodynamic models based on the SAFT equation together with (1) the concepts of continuous thermodynamics (2) molecular weight information on the oligomeric nature of the feed pitch were used to correlate the measured results. By using three adjustable parameters, solvent compositions and molecular weight distributions in each phase were calculated. Although the oligomeric model is able to qualitatively represent trends observed in the data, it cannot as yet be used to quantitatively predict phase compositions. Based on the characterizations of the supercritically extracted mesophases produced, selected fractions were melt-spun into round- and ribbon-shaped fibers using a laboratory-scale melt-spinning apparatus. It was found that a relatively narrow window of mesophase properties and compositions allowed fiber making without off-gassing. For a given spinnable mesophase, wide angle X-ray diffraction was used on as-spun fibers produced over a wide range of spinning temperatures to evaluate their potential to yield, after proper heat treatment, carbon fibers exhibiting superior transport properties. True statistical differences in the as-spun orientation (Z value) of two fiber sets spun from the same mesophase yielded, upon identical heat treatment, true differences in tensile moduli, electrical resistivity, and crystallographic parameters. Even though the heat treatment of the as-spun fibers was not optimized, final fibers with properties equal to those exhibited by Amoco's P-120 fibers were produced.

Dauche, Franck Michel

189

Introduction to Wavelet Reproducing Kernel Particle Methods.  

National Technical Information Service (NTIS)

As summarized, several different meshless methods have been proposed, including smooth particle hydrodynamics, diffuse elements, element free Galerkin (EFG), particle in cell methods (PIC), wavelets, reproducing kernel particle methods (RKPM) and wavelet ...

W. K. Liu

1995-01-01

190

Similarity of Skeletal Structures Observed in Laser-Produced Plasmas and High-Current Electric Discharges  

NASA Astrophysics Data System (ADS)

The paper reports on the presence of skeletal structures in the filtered x-ray pinhole images of plasma corona produced in former experiments [1] on irradiating the foils by a pulsed laser beam. These structures are shown to be similar to tubular and cartwheel-like structures previously found [2] in the visible light images of the plasma in various fusion plasmas (Z-pinch, plasma focus, tokamak). Such topological identity allows to draw a parallel between laser-produced plasmas and electric breakdown stage of various high-current electric discharges. This allows, in turn, to extend to the case of laser-produced plasmas some points of the hypothesis [3] which suggested the probable necessity to go beyond the frame of classical electrodynamics in describing the long-range (macroscopic) correlations/bonds in a broad range of plasmas. REFERENCES [1] Bolshov L.A., et. al., Sov. Phys. JETP 65 (1987) 1160; Burdonskii I.N., et. al., Laser and Part. Beams, 6(2) (1988) 327. [2] Kukushkin A.B., Rantsev-Kartinov V.A., Proc. 27-th EPS PPCF (2000) p2-029 p2-028 p2-051. [3] Kukushkin A.B., Rantsev-Kartinov V.A., Fusion Energy 1998 (IAEA, Vienna, 1999, IAEA-CSP-1/P, Vol. 3) p.1131; Proc. 26-th EPS PPCF (1999) p2-087.

Rantsev-Kartinov, V. A.; Kukushkin, A. B.

2001-10-01

191

Metabolic engineering of a thermophilic bacterium to produce ethanol at high yield.  

PubMed

We report engineering Thermoanaerobacterium saccharolyticum, a thermophilic anaerobic bacterium that ferments xylan and biomass-derived sugars, to produce ethanol at high yield. Knockout of genes involved in organic acid formation (acetate kinase, phosphate acetyltransferase, and L-lactate dehydrogenase) resulted in a strain able to produce ethanol as the only detectable organic product and substantial changes in electron flow relative to the wild type. Ethanol formation in the engineered strain (ALK2) utilizes pyruvate:ferredoxin oxidoreductase with electrons transferred from ferredoxin to NAD(P), a pathway different from that in previously described microbes with a homoethanol fermentation. The homoethanologenic phenotype was stable for >150 generations in continuous culture. The growth rate of strain ALK2 was similar to the wild-type strain, with a reduction in cell yield proportional to the decreased ATP availability resulting from acetate kinase inactivation. Glucose and xylose are co-utilized and utilization of mannose and arabinose commences before glucose and xylose are exhausted. Using strain ALK2 in simultaneous hydrolysis and fermentation experiments at 50 degrees C allows a 2.5-fold reduction in cellulase loading compared with using Saccharomyces cerevisiae at 37 degrees C. The maximum ethanol titer produced by strain ALK2, 37 g/liter, is the highest reported thus far for a thermophilic anaerobe, although further improvements are desired and likely possible. Our results extend the frontier of metabolic engineering in thermophilic hosts, have the potential to significantly lower the cost of cellulosic ethanol production, and support the feasibility of further cost reductions through engineering a diversity of host organisms. PMID:18779592

Shaw, A Joe; Podkaminer, Kara K; Desai, Sunil G; Bardsley, John S; Rogers, Stephen R; Thorne, Philip G; Hogsett, David A; Lynd, Lee R

2008-09-08

192

Synchronous objects for one flat thing, reproduced  

Microsoft Academic Search

Synchronous Objects for One Flat Thing, reproduced (http:\\/\\/synchronousobjects.osu.edu) is an interactive screen-based work developed by The Ohio State University's Advanced Computing Center for the Arts and Design (ACCAD) and the Department of Dance in collaboration with renowned choreographer William Forsythe. Pivoting on Forsythe's masterwork of visual complexity, One Flat Thing, Reproduced, as its research resource, the Synchronous Objects project seeks

Maria Palazzi; Norah Zuniga Shaw

2009-01-01

193

Tunable high-power fiber laser and its application to produce Brillouin fiber lasers  

NASA Astrophysics Data System (ADS)

A tunable continuous wave single-longitudinal-mode fiber laser is proposed and developed. A saturable absorber, as well as, an all-fiber Fabry-Perot filter was used in the laser cavity to reduce mode-hopping. The laser was tunable from 1565nm to 1575nm and could produce an output power of 300mW while still maintaining single-mode operation with no mode-hoping. The linewidth of the laser was ˜9 MHz. The stability of the laser based on the length of the saturable absorber and the modal structure has been explored. We developed two Brillouin fiber lasers using this laser as a pump source. A highly nonlinear photonic crystal fiber and a chalcogenide fiber were used as the nonlinear medium. The Brillouin fiber laser based on PCF could produce either single wavelength or multiwavelength laser outputs. Further, we investigated the coupling mechanism for the pump light into the chalcogenide glass fiber. In all cases the lasers were operated at room temperature.

Valiunas, Jonas Kestutis

194

Novel membrane-bound reporter molecule for sorting high producer cells by flow cytometry.  

PubMed

We developed a membrane bound reporter and selection molecule for sorting by fluorescence activated cell sorting (FACS) of cells producing a protein of interest. This molecule is composed of a transmembrane (TM) domain, fused on its extracellular end to a biotin mimetic peptide (BMP) and on its intracellular side to puromycin N-acetyl transferase (PAC). In this format BMP is displayed on the cell membrane surface and PAC faces the cell cytoplasm. BMP was detected and quantified on the cell surface by fluorescently labelled streptavidin, allowing cell sorting by FACS, according to the reporter expression level. The reporter and a gene of interest (GOI) were connected on the same transcript via an internal ribosomal entry site (IRES). The reporter expression level was found to correlate with that of the GOI, enabling sorting of high producer cells by FACS. Thus, the highest fluorescent cells sorted had also the highest protein of interest (POI) productivity level. © 2013 International Society for Advancement of Cytometry. PMID:23765751

Helman, Daniel; Toister-Achituv, Mira; Bar-Shimon, Meirav; Cohen, Benny; Otmi, Issaschar; Berger, Nir; Kalimi, Doron; Kimalov, Boaz; Medina, Tali; Sapir, Ashi; Rotemberg, Ofer; Zabavnik, Natalia; Zauberman, Arie; Smolarsky, Moshe

2013-06-13

195

High level compressive residual stresses produced in aluminum alloys by laser shock processing  

NASA Astrophysics Data System (ADS)

Laser shock processing (LSP) has been proposed as a competitive alternative technology to classical treatments for improving fatigue and wear resistance of metals. We present a configuration and results for metal surface treatments in underwater laser irradiation at 1064 nm. A convergent lens is used to deliver 1.2 J/cm 2 in a 8 ns laser FWHM pulse produced by 10 Hz Q-switched Nd:YAG, two laser spot diameters were used: 0.8 and 1.5 mm. Results using pulse densities of 2500 pulses/cm 2 in 6061-T6 aluminum samples and 5000 pulses/cm 2 in 2024 aluminum samples are presented. High level of compressive residual stresses are produced -1600 MPa for 6061-T6 Al alloy, and -1400 MPa for 2024 Al alloy. It has been shown that surface residual stress level is higher than that achieved by conventional shot peening and with greater depths. This method can be applied to surface treatment of final metal products.

Gomez-Rosas, G.; Rubio-Gonzalez, C.; Ocaña, J. L.; Molpeceres, C.; Porro, J. A.; Chi-Moreno, W.; Morales, M.

2005-11-01

196

Solar photo-thermal catalytic reactions to produce high value chemicals  

SciTech Connect

This report presents a summary of the research work accomplished to date on the utilization of solar photo-thermal energy to convert low cost chemical feedstocks into high $-value chemical products. The rationale is that the solar IR-VIS-UV spectrum is unique, supplying endothermic reaction energy as well as VIS-UV for photochemical activation. Chemical market analysis and product price distribution focused attention on speciality chemicals with prices >$1.00/lb, and a synthesis sequence of n-paraffins to aromatics to partial oxidized products. The experimental work has demonstrated that enhanced reaction effects result from VIS-UV irradiation of catalytically active V2O5/SiO2. Experiments of the past year have been on dehydrogenation and dehydrocyclization of n-paraffins to olefins and aromatics with preference for the latter. Recent results using n-hexane produced 95% conversion with 56% benzene; it is speculated that aromatic yield should reach {approximately}70% by further optimization. Pilot- and commercial-scale reactor configurations have been examined; the odds-on-favorite being a shallow fluid-bed of catalyst with incident radiation from the top. Sequencing for maximum cost effectiveness would be day-time endothermic followed by night-time exothermic reactions to produce the products.

Prengle, H.W. Jr.; Wentworth, W.E. [Houston Univ., TX (United States)

1992-04-01

197

Controlled tissue emulsification produced by high intensity focused ultrasound shock waves and millisecond boiling  

PubMed Central

In high intensity focused ultrasound (HIFU) applications, tissue may be thermally necrosed by heating, emulsified by cavitation, or, as was recently discovered, emulsified using repetitive millisecond boiling caused by shock wave heating. Here, this last approach was further investigated. Experiments were performed in transparent gels and ex vivo bovine heart tissue using 1, 2, and 3 MHz focused transducers and different pulsing schemes in which the pressure, duty factor, and pulse duration were varied. A previously developed derating procedure to determine in situ shock amplitudes and the time-to-boil was refined. Treatments were monitored using B-mode ultrasound. Both inertial cavitation and boiling were observed during exposures, but emulsification occurred only when shocks and boiling were present. Emulsified lesions without thermal denaturation were produced with shock amplitudes sufficient to induce boiling in less than 20 ms, duty factors of less than 0.02, and pulse lengths shorter than 30 ms. Higher duty factors or longer pulses produced varying degrees of thermal denaturation combined with mechanical emulsification. Larger lesions were obtained using lower ultrasound frequencies. The results show that shock wave heating and millisecond boiling is an effective and reliable way to emulsify tissue while monitoring the treatment with ultrasound.

Khokhlova, Tatiana D.; Canney, Michael S.; Khokhlova, Vera A.; Sapozhnikov, Oleg A.; Crum, Lawrence A.; Bailey, Michael R.

2011-01-01

198

Assessment of high heat-transfer evaporators as power plant condensers to produce abundant freshwater  

SciTech Connect

Energy requirements to produce abundant freshwater from saline water sources suggests the use of high heat-transfer evaporative condensers in power plants where sufficient waste heat is available for distillation. Review of current existence of such dual-purpose plants as well as a discussion of planning for future designs is presented. Computer programs utilizing available engineering equations and cost analysis for multieffect distillation plants have been developed and are presented with example problems. They are particularly useful for analysis of existing designs, and an additional computer code for optimization of new designs has been developed. The examples show appreciable improvement in lowering unit water cost of the product, as well as adjusting such variables as temperature, mass flow rates and evaporator areas. Preliminary computerized calculations show that a two-effect evaporator unit condensing 7 million pounds per hour of steam from a 1,000 MW power plant would produce 23 million gallons per day of freshwater at a cost of less than $1 per thousand gallons.

Laird, A.D.K.; Frisch, J.; Ensler, E.

1982-01-01

199

Fast Magnetic Reconnection in High-Energy-Density Laser-Produced Plasmas  

NASA Astrophysics Data System (ADS)

Recent experiments have observed magnetic reconnection in high-energy-density, laser-produced plasma bubbles [1,2], with reconnection rates observed to be much higher than can be explained by classical theory. This is a novel regime for magnetic reconnection study, characterized by extremely high magnetic fields, high plasma beta and strong, supersonic plasma inflow. Reconnection in this regime is investigated with particle-in-cell simulations. Collisionless simulations have identified two key ingredients, simultaneously present for the first time: two-fluid reconnection mediated by collisionless effects (that is, the Hall current and electron pressure tensor), and strong flux pile-up of the inflowing magnetic field [3]. These effects combine to yield reconnection rates independent of the nominal Alfvén speed (based on the magnetic field before interaction), and simply given by the dynamic time L/V, in qualitative agreement with the experiments. We present detailed simulations spanning the parameter ranges of the experiments, and further compare the results of simulations with and without binary collisions, in 2D and 3D. Finally we discuss plans for future laser-driven reconnection experiments.[4pt] [1] P. M. Nilson, et al, Phys. Rev. Lett. 97, 255001 (2006).[0pt] [2] C. K. Li, et al, Phys. Rev. Lett. 99, 055001 (2007).[0pt] [3] W. Fox, A. Bhattacharjee, K. Germaschewski, Phys. Rev. Lett. 106, 215003 (2011).

Fox, William

2011-11-01

200

Construction of lactose-assimilating and high-ethanol-producing yeasts by protoplast fusion  

SciTech Connect

The availability of a yeast strain which is capable of fermenting lactose and at the same time is tolerant to high concentrations of ethanol would be useful for the production of ethanol from lactose. Kluyveromyces fragilis is capable of fermenting lactose, but it is not as tolerant as Saccharomyces cerevisiae to high concentrations of ethanol. In this study, the authors have used the protoplast fusion technique to construct hybrids between auxotrophic strains of S. cerevisiae having high ethanol tolerance and an auxotrophic strain of lactose-fermenting K. fragilis isolated by ethyl methanesulfonate mutagenesis. The fusants obtained were prototrophic and capable of assimilating lactose and producing ethanol in excess of 13% (vol/vol). The complementation frequency of fusion was about 0.7%. Formation of fusants was confirmed by the increased amount of chromosomal DNA per cell. Fusants contained 8 x 10/sup -9/ to 16 x 10/sup -8/ ..mu..g of DNA per cell as compared with about 4 x 10/sup -8/ ..mu..g of DNA per cell for the parental strains, suggesting that multiple fusions had taken place.

Farahnak, F.; Seki, T.; Ryu, D.D.Y.; Ogrydziak, D.

1986-02-01

201

Process of high temperature synthesis in producing composite carbide powders for thermally sprayed coatings  

NASA Astrophysics Data System (ADS)

The paper presents the characterization of powders containing hard phases of chromium carbides in a NiCr matrix, intended for thermal spraying coatings. The synthesized composite powder containing hard phases and plastic matrix, produced in high-temperature synthesis with chosen powder metallurgy processes has been presented. Commercial materials, such as NiCr- CrxCy, are fabricated by means of agglomeration and sintering method. Processes of high temperature synthesis of Cr3C2, Cr7C3, Cr23C6 carbides combined with NiCr powder mechanical alloying are presented in the article. Parameters of the carbides synthesis were determined in the reactive -protective atmosphere. In the rotation- vibration mill, processes were conducted using grinding and appropriate mechanical alloying at variable amplitude. The standard and synthesized powders were thermally sprayed by HVOF method in Jet Kote II and Diamond Jet system. The structure and phase composition of the powders and coatings were determined by: light and scanning microscopy, X-ray phase analysis (RTG) and energy dispersive X-ray analysis (EDX). The structure and wear properties of HVOF sprayed coatings containing chromium carbides has been presented. The thermally sprayed coatings are characterized of wear resistance in abrasion and erosion tests. The sprayed coatings characterized high resistance in wear conditions.

Szyma?ski, K.; Formanek, B.

2011-05-01

202

Process and system for producing high-density pellets from a gaseous medium  

DOEpatents

A process and system for producing pellets of high density carbon dioxide or other gases utilize a chamber containing a plurality of cell-like freezing compartments within which ice is to be formed. A gas desired to be frozen into ice is introduced into the chamber while the internal pressure of the chamber is maintained at a level which is below the equilibrium triple pressure of the gas. The temperature of the freezing compartments is lowered to a temperature which is below the equilibrium vapor pressure temperature of the gas at the chamber pressure so that the gas condenses into ice within the compartments. The temperature of the freezing compartments is thereafter raised so that the ice is thereby released from and falls out of the compartments as pellets for collection.

Foster, Christopher A. (Clinton, TN)

1999-01-01

203

Highly efficient selenomethionine labeling of recombinant proteins produced in mammalian cells.  

PubMed

The advent of the multiwavelength anomalous diffraction phasing method has significantly accelerated crystal structure determination and has become the norm in protein crystallography. This method allows researchers to take advantage of the anomalous signal from diverse atoms, but the dominant method for derivative preparation is selenomethionine substitution. Several generally applicable, high-efficiency labeling protocols have been developed for use in the bacterial, yeast, and baculovirus/insect cell expression systems but not for mammalian tissue culture. As a large number of proteins of biomedical importance can only be produced in yields sufficient for X-ray diffraction experiments in mammalian expression systems, it becomes all the more important to develop such protocols. We therefore evaluated several variables that play roles in determining incorporation levels and report here a simple protocol for selenomethionine modification of proteins in mammalian cells routinely yielding >90% labeling efficiency. PMID:16823037

Barton, William A; Tzvetkova-Robev, Dorothea; Erdjument-Bromage, Hediye; Tempst, Paul; Nikolov, Dimitar B

2006-07-05

204

Method and source for producing a high concentration of positively charged molecular hydrogen or deuterium ions  

DOEpatents

A high concentration of positive molecular ions of hydrogen or deuterium gas is extracted from a positive ion source having a short path length of extracted ions, relative to the mean free path of the gas molecules, to minimize the production of other ion species by collision between the positive ions and gas molecules. The ion source has arrays of permanent magnets to produce a multi-cusp magnetic field in regions remote from the plasma grid and the electron emitters, for largely confining the plasma to the space therebetween. The ion source has a chamber which is short in length, relative to its transverse dimensions, and the electron emitters are at an even shorter distance from the plasma grid, which contains one or more extraction apertures.

Ehlers, Kenneth W. (Alamo, CA); Leung, Ka-Ngo (Hercules, CA)

1988-01-01

205

Observation of neutron bursts produced by laboratory high-voltage atmospheric discharge.  

PubMed

For the first time the emission of neutron bursts in the process of high-voltage discharge in air was observed. Experiments were carried out at an average electric field strength of ?1??MV·m^{-1} and discharge current of ?10??kA. Two independent methods (CR-39 track detectors and plastic scintillation detectors) registered neutrons within the range from thermal energies up to energies above 10 MeV and with an average flux density of ?10^{6}??cm^{-2} per shot inside the discharge zone. Neutron generation occurs at the initial phase of the discharge and correlates with x-ray generation. The data obtained allow us to assume that during the discharge fast neutrons are mainly produced. PMID:24074098

Agafonov, A V; Bagulya, A V; Dalkarov, O D; Negodaev, M A; Oginov, A V; Rusetskiy, A S; Ryabov, V A; Shpakov, K V

2013-09-12

206

Observation of Neutron Bursts Produced by Laboratory High-Voltage Atmospheric Discharge  

NASA Astrophysics Data System (ADS)

For the first time the emission of neutron bursts in the process of high-voltage discharge in air was observed. Experiments were carried out at an average electric field strength of ˜1MV·m-1 and discharge current of ˜10kA. Two independent methods (CR-39 track detectors and plastic scintillation detectors) registered neutrons within the range from thermal energies up to energies above 10 MeV and with an average flux density of ?106cm-2 per shot inside the discharge zone. Neutron generation occurs at the initial phase of the discharge and correlates with x-ray generation. The data obtained allow us to assume that during the discharge fast neutrons are mainly produced.

Agafonov, A. V.; Bagulya, A. V.; Dalkarov, O. D.; Negodaev, M. A.; Oginov, A. V.; Rusetskiy, A. S.; Ryabov, V. A.; Shpakov, K. V.

2013-09-01

207

High precision Penning trap mass spectrometry of rare isotopes produced by projectile fragmentation  

NASA Astrophysics Data System (ADS)

The Low Energy Beam and Ion Trap (LEBIT) is the only present facility to combine high precision Penning trap mass spectrometry with fast beam projectile fragmentation. Located at the National Superconducting Cyclotron Laboratory (NSCL), LEBIT is able to measure radionuclides produced in a chemically independent process with minimal decay losses. Recent exotic mass measurements include 66As, 63-66Fe, and 32Si. 66As is a new candidate to test the Conserved Vector Current (CVC) hypothesis. The masses of the neutron-rich iron isotopes provide additional information about the mass surface and the subshell closure at N = 40. 32Si is a member of the A = 32, T = 2 quintet; its measurement permits the most stringent test of the validity of the isobaric multiplet mass equation (IMME). An overview of some recent measurements will be presented as well as advanced techniques for ion manipulation.

Kwiatkowski, A. A.; Barquest, B. R.; Block, M.; Bollen, G.; Campbell, C. M.; Ferrer, R.; Lincoln, D. L.; Morrissey, D. J.; Pang, G. K.; Redshaw, M.; Ringle, R.; Schwarz, S.; Savory, J.

2011-09-01

208

High-silicon steel produced by hot dipping and diffusion annealing  

NASA Astrophysics Data System (ADS)

Steels with high Si content (up to 6.5% Si) are excellent soft magnetic materials, however, as the Si content is increased, the material becomes extremely brittle and it is very difficult to produce thin sheet by conventional rolling. An alternative production route has been developed through hot dipping in a high Si-bath followed by diffusion annealing. Experiments were carried out in a hot dip simulator using as substrate a steel with 0.35 mm thickness and 3.2% Si. Samples were dipped in an Al-Si hypereutectic bath at 800 °C for different times. After dipping, the coating consists of Fe-Al-Si phases and primary silicon crystals within a matrix of eutectic Al-Si. During a first annealing inside the hot dip simulator, diffusion of Si and Al into the substrate and phase transformation occurs in the layer producing a series of ternary intermetallics of the Fe-Si-Al system. A second annealing was performed outside the hot dip simulator under vacuum at 1250 °C with different holding times. This diffusion annealing allows the homogenisation of the composition obtaining a homogeneous concentration of 6%-7% Si and/or 2%-5% Al over the thickness in function of the previous hot-dip parameters. The material was characterized by SEM. Magnetic properties were measured and it was shown that the magnetic losses after hot dipping and diffusion annealing were reduced at 50 Hz from 3.7 W/kg (original material) to 0.64 W/kg (1 T), and at 400 Hz from 47 W/kg (original material) to 10 W/kg (1 T).

Ros-Yañez, T.; Houbaert, Y.; Gómez Rodríguez, V.

2002-05-01

209

Wave propagation software, computational science, and reproducible research  

Microsoft Academic Search

Wave propagation algorithms are a class of high-resolution finite volume methods for solving hyperbolic partial differential equations arising in diverse applications. The development and use of the clawpack software implementing these methods serves as a case study for a more general discussion of mathematical aspects of software development and the need for more reproducibility in computational research. Sample applications discussed

Randall J. LeVeque

2006-01-01

210

Technique for increasing reproducibility in EPR dosimetry of tooth enamel  

Microsoft Academic Search

Variations in several electron paramagnetic resonance (EPR) spectral parameters of importance in retrospective dosimetry of tooth enamel were measured using instrumentation and methodologies designed to maximize measurement reproducibility. Measurements were made using accessory EPR equipment that can be readily constructed with little more than a variable power supply, a geared down motor and some high-purity CaO. Spectroscopic precision is considerably

R. B. Hayes; E. H. Haskell; A. A. Romanyukha; G. H. Kenner

1998-01-01

211

Optical microplates for high-throughput screening of photosynthesis in lipid-producing algae.  

PubMed

It is well known that biological systems respond to chemical signals as well as physical stimuli. The workhorses of high throughput screening, microplates and pipetting robots, are well suited for screening chemical stimuli; however, there are fewer options for screening physical stimuli, particularly those which involve temporal patterns. This paper presents an optical microplate for photonic high-throughput screening. The system provides addressable intensity and temporal control of LED light emission in each well, and operates on standard black-wall clear-bottom 96-well microplates, which prevent light spillover. Light intensity can be controlled to 7-bit resolution (128 levels), with a maximum intensity of 120 mE cm(-2). The temporal resolution, useful for studying dynamics of light-driven bioprocesses, can be as low as 10 ?s. The microplate is used for high-throughput studies of light-dependent growth rates and photosynthetic efficiency in the model organism Dunaliella tertiolecta, a lipid-producing algae of interest in 2(nd) generation biofuels. By conducting 96 experiments in parallel, photoirradiance studies, which would require 2 years using conventional tools, can be completed in <2 weeks. In a 12 day culture, algal growth rates increase with total photon flux, as expected. Interestingly, the lipid production efficiency, defined as lipid production per unit photon flux per capita, increases nearly 5 fold at low light intensity (constant light) and at low duty cycle (pulsed light). High throughput protocols enabled by this system are conducive to systematic studies and discovery in the fields of photobiology and photochemistry. PMID:22971571

Chen, Meng; Mertiri, Taulant; Holland, Thomas; Basu, Amar S

2012-10-21

212

Selenium bioavailability from naturally produced high-selenium peas and oats in selenium-deficient rats.  

PubMed

This study determined the bioavailability of selenium (Se) from yellow peas and oats harvested from the high-Se soil of South Dakota, United States. The Se concentrations were 13.5 ± 0.2 and 2.5 ± 0.1 mg/kg (dry weight) for peas and oats, respectively. Male weanling Sprague-Dawley rats were depleted of Se by feeding them a 30% Torula yeast-based diet (4.1 ?g Se/kg) for 56 days, and then they were replenished with Se for an additional 50 days by feeding them the same diet supplemented with 20, 30, or 40 ?g Se/kg from peas or oats, respectively. Selenium bioavailability was determined on the basis of the restoration of Se-dependent enzyme activities and tissue Se concentrations in Se-depleted rats, comparing those responses for yellow peas and oats to those for l-selenomethionine (SeMet; used as a reference) by using a slope-ratio method. Dietary supplementation with peas or oats resulted in linear or log-linear, dose-dependent increases in glutathione peroxidase activities in blood and liver and in thioredoxin reductase activity in liver. Supplementation with peas or oats resulted in linear or log-linear, dose-dependent increases in Se concentrations of plasma, liver, gastrocnemius muscle, and kidneys. The overall bioavailability was approximately 88% for Se from yellow peas and 92% from oats, compared to SeMet. It was concluded that Se from naturally produced high-Se yellow peas or oats is highly bioavailable in this model and that these high-Se foods may be a good dietary source of Se. PMID:21553810

Yan, Lin; Johnson, LuAnn K

2011-05-17

213

Coupled-Multiplier Accelerator Produces High-Power Electron Beams for Industrial Applications  

SciTech Connect

The coupled multiplier is a new approach to efficient generation of MeV d.c. power for accelerator applications. High voltage is produced by a series of modules, each of which consists of a high-power alternator, step-up transformer, and 3-phase multiplier circuit. The alternators are connected mechanically along a rotating shaft, and connected by insulating flexible couplers. This approach differs from all previous d.c. technologies in that power is delivered to the various stages of the system mechanically, rather than through capacitive or inductive electrical coupling. For this reason the capital cost depends linearly on required voltage and power, rather than quadratically as with conventional technologies. The CM technology enables multiple electron beams to be driven within a common supply and insulating housing. MeV electron beam is extremely effective in decomposing organic contaminants in water. A 1 MeV, 100 kW industrial accelerator using the CM technology has been built and is being installed for treatment of wastewater at a petrochemical plant.

Hatridge, M.; McIntyre, P.; Roberson, S.; Sattarov, A.; Thomas, E.; Meitzler, Charles [Department of Physics, Texas A and M University (United States); Department of Physics, Sam Houston State University (United States)

2003-08-26

214

Method and source for producing a high concentration of positively charged molecular hydrogen or deuterium ions  

DOEpatents

One principal object of the present invention is to provide a novel method and apparatus for generating a high concentration of H/sub 2//sup +/ or D/sub 2//sup +/ ions by using a new and improved multicusp ion source. The basic principle in achieving a high percentage of H/sub 2//sup +/ or D/sub 2//sup +/ ions is to extract them from the source as soon as they are produced. Otherwise they will react with background gas molecules to form tri-atomic ions H/sub 3//sup +/ or D/sub 3//sup +/ or be dissociated by electrons. The former reaction H/sub 2//sup +/ + H/sub 2/ ..-->.. H/sub 3//sup +/ + H can have a very short mean free path length lambda. Assuming a background neutral gas density of approximately 3.3 x 10/sup 13/ cm/sup -3/ and a cross-section sigma of approximately 6 x 10/sup -15/ cm/sup 2/, lambda = (n/sub 0/ sigma)/sup -1/ is estimated to be about 5 cm. Thus the distance traversed by the H/sub 2//sup +/ ion before it arrives at the extractor electrode cannot exceed this value. This in turn sets a limit on the length of the source chamber.

Ehlers, K.W.; Leung, K.N.

1983-07-26

215

Radionuclide characterization studies of radioactive waste produced at high-energy accelerators  

NASA Astrophysics Data System (ADS)

The European Laboratory for Particle Physics (CERN) has been operating accelerators for high-energy physics both on Swiss and French territory for over 50 years. Due to the interaction of the particle beams with matter, the accelerator components and the surroundings become activated and shall be treated as radioactive waste once the end of their operational lifetime is reached. For disposal towards the final repositories the radioactive waste legislation of both CERN Host-States requires the knowledge of the radionuclide inventory. This paper discusses the studies that are carried out at CERN for the characterization of the metallic radioactive waste produced every year in the several high-energy accelerators. The radionuclide inventory as well as the specific activity of radioactive waste originating from accelerators varies depending on the accelerated beam, on the location of the material with respect to the beam losses and the decay time already elapsed. The approach proposed at CERN is based on an estimate of the specific activity per radionuclide with the Monte-Carlo code FLUKA, by simulating the radiation environment to which the radioactive waste was exposed during its operational lifetime. This method has been validated for the CERN ISOLDE facility by both ?-spectrometry and Monte-Carlo simulation of the target. The use of this method in those cases where the irradiation conditions are not known with sufficient precision requires careful extrapolation based on additional dose-rate and gamma-spectrometry measurements.

Ulrici, L.; Brugger, M.; Otto, Th.; Roesler, S.

2006-06-01

216

Producing High-Accuracy Lattice Models from Protein Atomic Coordinates Including Side Chains  

PubMed Central

Lattice models are a common abstraction used in the study of protein structure, folding, and refinement. They are advantageous because the discretisation of space can make extensive protein evaluations computationally feasible. Various approaches to the protein chain lattice fitting problem have been suggested but only a single backbone-only tool is available currently. We introduce LatFit, a new tool to produce high-accuracy lattice protein models. It generates both backbone-only and backbone-side-chain models in any user defined lattice. LatFit implements a new distance RMSD-optimisation fitting procedure in addition to the known coordinate RMSD method. We tested LatFit's accuracy and speed using a large nonredundant set of high resolution proteins (SCOP database) on three commonly used lattices: 3D cubic, face-centred cubic, and knight's walk. Fitting speed compared favourably to other methods and both backbone-only and backbone-side-chain models show low deviation from the original data (~1.5?Å RMSD in the FCC lattice). To our knowledge this represents the first comprehensive study of lattice quality for on-lattice protein models including side chains while LatFit is the only available tool for such models.

Mann, Martin; Saunders, Rhodri; Smith, Cameron; Backofen, Rolf; Deane, Charlotte M.

2012-01-01

217

Cyanobacteria produce a high variety of hepatotoxic peptides in lichen symbiosis.  

PubMed

Lichens are symbiotic associations between fungi and photosynthetic algae or cyanobacteria. Microcystins are potent toxins that are responsible for the poisoning of both humans and animals. These toxins are mainly associated with aquatic cyanobacterial blooms, but here we show that the cyanobacterial symbionts of terrestrial lichens from all over the world commonly produce microcystins. We screened 803 lichen specimens from five different continents for cyanobacterial toxins by amplifying a part of the gene cluster encoding the enzyme complex responsible for microcystin production and detecting toxins directly from lichen thalli. We found either the biosynthetic genes for making microcystins or the toxin itself in 12% of all analyzed lichen specimens. A plethora of different microcystins was found with over 50 chemical variants, and many of the variants detected have only rarely been reported from free-living cyanobacteria. In addition, high amounts of nodularin, up to 60 ?g g(-1), were detected from some lichen thalli. This microcystin analog and potent hepatotoxin has previously been known only from the aquatic bloom-forming genus Nodularia. Our results demonstrate that the production of cyanobacterial hepatotoxins in lichen symbiosis is a global phenomenon and occurs in many different lichen lineages. The very high genetic diversity of the mcyE gene and the chemical diversity of microcystins suggest that lichen symbioses may have been an important environment for diversification of these cyanobacteria. PMID:22451908

Kaasalainen, Ulla; Fewer, David P; Jokela, Jouni; Wahlsten, Matti; Sivonen, Kaarina; Rikkinen, Jouko

2012-03-26

218

Climate factors affecting conception rate of high producing dairy cows in northeastern Spain.  

PubMed

Summer heat stress is a main factor related to low conception rate in high producing dairy herds in warm areas worldwide. We assessed the impact of several climate variables on conception rate in high producing dairy cows in northeastern Spain by examining 10,964 inseminations. The temperature-humidity index (THI) was compared with maximum temperature in terms of its efficiency at predicting conception rate. The following data were recorded for each animal: herd, lactation number, insemination number, insemination date, inseminating bull, and AI technician along with climate variables such as mean and maximum temperatures, rainfall, mean and maximum THI for individual time points Days 7 to 1 before insemination, the day of insemination and 1, 2 and 3 days after insemination. Averages were also established for the following periods: from 7 days before insemination to the insemination day, from 3 days before insemination to the insemination day and from the insemination day to 3 days postinsemination. Based on the odds ratios, the likelihood of conception rate increased significantly by factors of 1.48, 1.47, 1.5, and 1.1 for the respective maximum THI classes <70, 71-75, 76-80, and 81-85 only on Day 3 before AI, while on the insemination day, it increased by factors of 1.73, 1.53, 1.11, and 1.3 for the respective maximum THI classes <70, 71-75, 76-80, and 81-85. In a subsequent logistic regression excluding mean and maximum THI, the effectiveness of temperature at predicting conception rate was evaluated. Although high, the fit of the second logistic regression model was slightly lower than that of the full model (P=0.88 versus P=0.98, respectively) and the information provided by the THI model. The likelihood of conception rate increased significantly by factors of 1.5, 1.2, 1.0, 1.0 for the respective maximum temperature classes <20, 21-25, 26-30, 31-35 degrees C on Day 1 after AI. The choice of the THI or temperature to monitor the farm environment would have to depend on the particular farm and situation. In our study conditions, the use of maximum temperature alone gives a new point of view regarding the information provided by the THI variables. PMID:17412409

García-Ispierto, I; López-Gatius, F; Bech-Sabat, G; Santolaria, P; Yániz, J L; Nogareda, C; De Rensis, F; López-Béjar, M

2007-04-06

219

Reproducible measurements of MPI performance characteristics.  

SciTech Connect

In this paper we describe the difficulties inherent in making accurate, reproducible measurements of message-passing performance. We describe some of the mistakes often made in attempting such measurements and the consequences of such mistakes. We describe mpptest, a suite of performance measurement programs developed at Argonne National Laboratory, that attempts to avoid such mistakes and obtain reproducible measures of MPI performance that can be useful to both MPI implementers and MPI application writers. We include a number of illustrative examples of its use.

Gropp, W.; Lusk, E.

1999-06-25

220

Reproducibility of multifocal VEP latency using different stimulus presentations.  

PubMed

The aims of the article were to study the reproducibility of latency of multifocal visual evoked potential (mfVEP) recorded using different stimulus presentations and to identify the peak with least variability. Ten normal subjects, aged between 22 and 52 years (mean age 32 ± 8.37 years), participated in the study. All subjects underwent mfVEP testing with pattern reversal and pattern pulse stimulus presentations. The stimulus subtends 26° from fixation and includes 24 segments. Only the vertical channel was recorded on all subjects. Testing was repeated after 1-2 weeks. Only the right eye of all subjects was analysed. Segments with low signal-to-noise ratios (SNR < 1.5) were excluded from analysis. The latencies were analysed to confirm values from the same peak for the two tests. The latency values were then analysed for the start of the response, the first peak and the second peak. The waveforms were reproducible throughout the field. Reproducibility of latency at the "start of the response" was significantly lesser than the first and the second peaks studied, while the reproducibility of latency at the first peak was not statistically different from the second peak for either pattern reversal or pattern pulse stimulation. The latency values were not different between the first and the second sessions for either pattern reversal or pattern pulse stimulation for any of the peaks. The pattern reversal stimulus presentation produced less variability in latency. The first peak is the most reproducible among the three measures in both the stimulus presentation. PMID:22669286

Sriram, Prema; Klistorner, Alexander; Arvind, Hemamalini; Graham, Stuart L

2012-06-06

221

High quality shocks produced by lasers: Application to equations of state measurements  

SciTech Connect

High quality shock waves with direct and indirect laser drive were generated. We used Phase Zone Plate smoothing technique in the case of direct drive and thermal X-rays from laser heated cavities in the case of indirect drive. The possibility of producing homogeneous, steady shock waves without significant preheating effects with both methods has been proved. Such shocks have been used to test a new method for EOS experiments. Indeed the first simultaneous measurement of colour temperature and shock velocity in laser driven shocks is presented. The two parameters have been measured on each laser shot respectively from the target rear side emissivity in two spectral channels and by using stepped targets. A very good planarity of the shock has been ensured by using the Phase Zone Plate smoothing technique. A simple model describing the shock luminosity has been developed in order to estimate the shock temperature from the experimental rear side emissivities. Results have been compared to temperatures determined from shock velocity for materials of known equation of state.

Bossi, S.; Batani, D.; Bernardinello, A.; Muller, L.; Benuzzi, A.; Koenig, M.; Faral, B.; Hall, T. A.; Loewer, Th. [INFM, via Celoria 16, 20133 Milan (Italy); Laboratoire pour l'Utilisation des Laser Intenses, Ecole Polytechnique, 91128 Palaiseau (France); University of Essex, Dept. of Physics, Wivenhoe Park, 504 3SQ Colchester (United Kingdom); Max Plank Institut fur Quantenoptik, Garching, Munich (Germany)

1998-02-20

222

Life Cycle Analysis of High Quality Recycled Aggregate Produced byHeating and Rubbing Method  

NASA Astrophysics Data System (ADS)

Most of demolished concrete is recycled as road subbase, but its generation is expected to increase rapidly and exceed the demand of road subbase in a near future. To promote the recycling of concrete, the technology to produce high quality recycled aggregate by the heating and rubbing method has been developed. In this method, demolished concrete is heated up to about 300°C in a heater to make cement paste brittle with its dehydration. The heated concrete is then rubbed in two mills to recover the recycled aggregate, while the paste is removed from the surface of aggregate and collected as cement fine powder. In this method, much energy is consumed to heat and rub concrete; however, the cement fine powder is utilized for a soil stabilizer and cement raw materials, so that the environmental load is reduced in cement manufacturing. The life cycle analysis of the recycled aggregate is carried out to evaluate this technology. As a result, the life cycle CO2 is a negative value because the deduction of CO2 emission in cement manufacturing by the powder is much large. This technology is proved to be very effective to reduce CO2.

Shima, Hirokazu; Matsuhashi, Ryuji; Yoshida, Yoshikuni; Tateyashiki, Hisashi

223

Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts  

DOEpatents

High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

Jansen, Kai W. (Lawrenceville, NJ); Maley, Nagi (Exton, PA)

2000-01-01

224

Producing thin film photovoltaic modules with high integrity interconnects and dual layer contacts  

DOEpatents

High performance photovoltaic modules are produced with improved interconnects by a special process. Advantageously, the photovoltaic modules have a dual layer back (rear) contact and a front contact with at least one layer. The front contact and the inner layer of the back contact can comprise a transparent conductive oxide. The outer layer of the back contact can comprise a metal or metal oxide. The front contact can also have a dielectric layer. In one form, the dual layer back contact comprises a zinc oxide inner layer and an aluminum outer layer and the front contact comprises a tin oxide inner layer and a silicon dioxide dielectric outer layer. One or more amorphous silicon-containing thin film semiconductors can be deposited between the front and back contacts. The contacts can be positioned between a substrate and an optional superstrate. During production, the transparent conductive oxide layer of the front contact is scribed by a laser, then the amorphous silicon-containing semiconductors and inner layer of the dual layer back contact are simultaneously scribed and trenched (drilled) by the laser and the trench is subsequently filled with the same metal as the outer layer of the dual layer back contact to provide a superb mechanical and electrical interconnect between the front contact and the outer layer of the dual layer back contact. The outer layer of the dual layer back contact can then be scribed by the laser. For enhanced environmental protection, the photovoltaic modules can be encapsulated.

Jansen, Kai W. (Lawrenceville, NJ); Maley, Nagi (Exton, PA)

2001-01-01

225

Thermophysical property measurement at high temperatures by laser-produced plasmas  

SciTech Connect

Excitation by a high-power laser pulse of a material surface generates a sequence of plasma, fluid flow, and acoustic events. These are well separated in time, and their detection and analysis can lead to determination of material properties of the condensed phase target. We have developed a new methodology for real-time determination of molten metal composition by time-resolved spectroscopy of laser-produced plasmas (LPP). If the laser pulse is shaped in such a way that the movement of the bulk surface due to evaporation is kept in pace with the thermal diffusion front advancing into the interior of the target, the LPP plume becomes representative of the bulk in elemental composition. In addition, the mass loss due to LPP ablation is very well correlated with the thermal diffusivity of the target matter. For several elemental solid specimens, we show that the product of the ablation thickness and heat of formation is proportional to the thermal diffusivity per unit molecular weight. Such measurements can be extended to molten metal specimens if the mass loss by ablation, density, heat of formation, and molecular weight can be determined simultaneously. The results from the solid specimen and the progress with a levitation-assisted molten metal experiment are presented.

Kim, Y.W. [Lehigh Univ., Bethehem, PA (United States)

1993-05-01

226

Formation of TiOx films produced by high-power pulsed magnetron sputtering  

NASA Astrophysics Data System (ADS)

Formation of thin TiOx films produced by pulsed planar magnetron sputtering deposition is reported in this paper. The formation process and layer growth were controlled by (i) the ratio of reactive O2 in Ar/O2 working gas mixture and (ii) the pressure in the vacuum chamber. The magnetron, operated in a high-power pulse mode with a low repetition frequency of 250 Hz, reached maxima peak current Ip ~ 50 A and magnetron current density peaks at ip ~ 1 A cm-2. Particular spectral lines (Ar = 420.07 nm, Ar+ = 487.98 nm, Ti = 518.96 nm) emitted by the discharge were investigated using time-resolved photon counting measurements. The phases of deposited TiOx films were determined by grazing incidence x-ray diffractometry and thickness and density were calculated from x-ray reflectometry measurements; in addition composition and chemical bounds were revealed by x-ray photoelectron spectroscopy. The film diagnostics survey the existence of different crystalline phases in the Ti-O system and their formation. Discharge properties for example, deposition rate and time evolution of discharge current are also discussed.

Stra?ák, Vít?zslav; Quaas, Marion; Wulff, Harm; Hubi?ka, Zden?k; Wrehde, Stefan; Tichý, Milan; Hippler, Rainer

2008-03-01

227

Identification of carotenoids with high antioxidant capacity produced by extremophile microorganisms.  

PubMed

In this study, the carotenoids produced by the extremophile microorganisms Halococcus morrhuae, Halobacterium salinarium and Thermus filiformis were separated and identified by high-performance liquid chromatography connected to a diode array detector and a tandem mass spectrometer. The in vitro scavenging capacity of the carotenoid extracts against radical and non-radical species was evaluated. In halophilic microorganisms, the following carotenoids were identified: bacterioruberin, bisanhydrobacterioruberin, trisanhydrobacterioruberin and their derivatives. In the thermophilic bacterium, the carotenoids all-trans-zeaxanthin, zeaxanthin monoglucoside, thermozeaxanthins and thermobiszeaxanthins were identified. The antioxidant capacities of the carotenoid extracts of H. morrhuae (trolox equivalent antioxidant capacity = 5.07 and IC(50) = 0.85 ?g mL(-1)) and H. salinarium (trolox equivalent antioxidant capacity = 5.28 and IC(50) = 0.84 ?g mL(-1)) were similar and higher than those of the bacterium T. filiformis (trolox equivalent antioxidant capacity = 2.87 and IC(50) = 2.41 ?g mL(-1)). This difference is related to the presence of acyclic carotenoids with both large numbers of conjugated double bounds and of hydroxyl groups in the major carotenoid of the halophilic microorganisms. PMID:22805960

Mandelli, Fernanda; Miranda, Viviane S; Rodrigues, Eliseu; Mercadante, Adriana Z

2011-12-31

228

Magnetic reconnection in high-energy-density laser-produced plasmas  

SciTech Connect

Recently, novel experiments on magnetic reconnection have been conducted in laser-produced plasmas in a high-energy-density regime. Individual plasma bubbles self-generate toroidal, mega-gauss-scale magnetic fields through the Biermann battery effect. When multiple bubbles are created at small separation, they expand into one another, driving reconnection of this field. Reconnection in the experiments was reported to be much faster than allowed by both Sweet-Parker, and even Hall-MHD theories, when normalized to the nominal magnetic fields self-generated by single bubbles. Through particle-in-cell simulations (both with and without a binary collision operator), we model the bubble interaction at parameters and geometry relevant to the experiments. This paper discusses in detail the reconnection regime of the laser-driven experiments and reports the qualitative features of simulations. We find substantial flux-pileup effects, which boost the relevant magnetic field for reconnection in the current sheet. When this is accounted for, the normalized reconnection rates are much more in line with standard two-fluid theory of reconnection. At the largest system sizes, we additionally find that the current sheet is prone to breakup into plasmoids.

Fox, W.; Bhattacharjee, A.; Germaschewski, K. [Center for Integrated Computation and Analysis of Reconnection and Turbulence, and Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of New Hampshire, Durham, New Hampshire 03824 (United States)

2012-05-15

229

Highly Efficient Sex Chromosome Interchanges Produced By I-CreI Expression in Drosophila  

PubMed Central

The homing endonuclease I-CreI recognizes a site in the gene encoding the 23S rRNA of Chlamydomonas reinhardtii. A very similar sequence is present in the 28S rRNA genes that are located on the X and Y chromosomes of Drosophila melanogaster. In this work we show that I-CreI expression in Drosophila is capable of causing induced DNA damage and eliciting cell cycle arrest. Expression also caused recombination between the X and Y chromosomes in the heterochromatic regions where the rDNA is located, presumably as a result of a high frequency of double-strand breaks in these regions. Approximately 20% of the offspring of males expressing I-CreI showed exceptional inheritance of X- and Y-linked markers, consistent with chromosome exchange at rDNA loci. Cytogenetic analysis confirmed the structures of many of these products. Exchange between the X and Y chromosomes can be induced in males and females to produce derivative-altered Y chromosomes, attached-XY, and attached-X chromosomes. This method has advantages over the traditional use of X rays for generating X-Y interchanges because it is very frequent and it generates predictable products.

Maggert, Keith A.; Golic, Kent G.

2005-01-01

230

Polyandrous females benefit by producing sons that achieve high reproductive success in a competitive environment.  

PubMed

Females of many taxa often copulate with multiple males and incite sperm competition. On the premise that males of high genetic quality are more successful in sperm competition, it has been suggested that females may benefit from polyandry by accruing 'good genes' for their offspring. Laboratory studies have shown that multiple mating can increase female fitness through enhanced embryo viability, and have exposed how polyandry influences the evolution of the ejaculate. However, such studies often do not allow for both female mate choice and male-male competition to operate simultaneously. Here, I took house mice (Mus domesticus) from selection lines that had been evolving with (polygamous) and without (monogamous) sperm competition for 16 generations and, by placing them in free-ranging enclosures for 11 weeks, forced them to compete for access to resources and mates. Parentage analyses revealed that female reproductive success was not influenced by selection history, but there was a significant paternity bias towards males from the polygamous selection lines. Therefore, I show that female house mice benefit from polyandry by producing sons that achieve increased fitness in a semi-natural environment. PMID:21288948

Firman, Renée C

2011-02-02

231

High Brightness Imaging for Real Time Measurement of Shock, Particle, and Combustion Fronts Produced by Enhanced Blast Explosives.  

National Technical Information Service (NTIS)

High brightness imaging (HBI) has been used to study the structure of the leading shock, particles immediately behind the leading shock, and the following contact surface of combustion front (i.e., the 'fireball') produced during testing of enhanced blast...

K. L. McNesby B. E. Homan R. E. Lottero

2004-01-01

232

Moderate volume of high relative training intensity produces greater strength gains compared with low and high volumes in competitive weightlifters.  

PubMed

The purpose of this study was to examine the effect of 3 volumes of heavy resistance, average relative training intensity (expressed as a percentage of 1 repetition maximum that represented the absolute kilograms lifted divided by the number of repetitions performed) programs on maximal strength (1RM) in Snatch (Sn), Clean & Jerk (C&J), and Squat (Sq). Twenty-nine experienced (>3 years), trained junior weightlifters were randomly assigned into 1 of 3 groups: low-intensity group (LIG; n = 12), moderate-intensity group (MIG; n = 9), and high-intensity group (HIG; n = 8). All subjects trained for 10 weeks, 4-5 days a week, in a periodized routine using the same exercises and training volume (expressed as total number of repetitions performed at intensities equal to or greater than 60% of 1RM), but different programmed total repetitions at intensities of >90-100% of 1RM for the entire 10-week period: LIG (46 repetitions), MIG (93 repetitions), and HIG (184 repetitions). During the training period, MIG and LIG showed a significant increase (p < 0.01-0.05) for C&J (10.5% and 3% for MIG and LIG, respectively) and Sq (9.5% and 5.3% for MIG and LIG, respectively), whereas in HIG the increase took place only in Sq (6.9%, p < 0.05). A calculation of effect sizes revealed greater strength gains in the MIG than in HIG or LIG. There were no significant differences between LIG and HIG training volume-induced strength gains. All the subjects in HIG were unable to fully accomplish the repetitions programmed at relative intensities greater than 90% of 1RM. The present results indicate that short-term resistance training using moderate volumes of high relative intensity tended to produce higher enhancements in weightlifting performance compared with low and high volumes of high relative training intensities of equal total volume in experienced, trained young weightlifters. Therefore, for the present population of weightlifters, it may be beneficial to use the MIG training protocol to improve the weightlifting program at least in a short-term (10 weeks) cycle of training. PMID:16503695

González-Badillo, Juan José; Izquierdo, Mikel; Gorostiaga, Esteban M

2006-02-01

233

Medium- and high-pressure gauges and transducers produced by laser welding technology  

NASA Astrophysics Data System (ADS)

Industrial manufacturers produce many types of pressure gauges and transducers according to the applications, for gas or liquid, for high-medium and low pressure ranges. Nowadays the current production technology generally prefers to weld by micro TIG source the metallic corrugated membranes to the gauge or transducer bodies for the products, operating on the low pressure or medium pressure ranges. For the other ones, operating to high pressure range, generally the two components of the transducers are both threaded only and threaded and then circularly welded by micro TIG for the other higher range, till to 1000 bar. In this work the products, operating on the approximately equals 30 divided by 200 bar, are considered. These, when assembled on industrial plants, as an outcome of a non-correct operating sequence, give a 'shifted' electrical signal. This is due to a shift of the 'zero electrical signal' that unbalances the electrical bridge - thin layer sensor - that is the sensitive part of the product. Moreover, for the same problem, often some mechanical settlings of the transducer happen during the first pressure semi-components, with an increasing of the product manufacturing costs. In light of all this, the above referred, in this work the whole transducer has been re-designed according to the specific laser welding technology requirements. On the new product no threaded parts exist but only a circular laser welding with a full penetration depth about 2.5 divided by 3 mm high. Three different alloys have been tested according to the applications and the mechanical properties requested to the transducer. By using a 1.5 KW CO2 laser system many different working parameters have been evaluated for correlating laser parameters to the penetration depths, crown wides, interaction laser-materia times, mechanical and metallurgical properties. Moreover during the laser welding process the measurements of the maximum temperature, reached by the transducer top, has been read and recorded. At least some transducers, before the usual destructive testings, have been undertaken to many pressure test cycles to verify any pressure drops, the transducer sealing and the total quality of the new product.

Daurelio, Giuseppe; Nenci, Fabio; Cinquepalmi, Massimo; Chita, Giuseppe

1998-07-01

234

The Reproducibility of Sputum Gram Film Interpretation  

Microsoft Academic Search

Objectives: To evaluate the reproducibility with which microbiologists interpret Gram-stained sputa and examine the effect of the smear preparation method.Methods: Two hundred and ten coded slides prepared directly from a purulent portion of sputum (DS) and 140 slides prepared after homogenization of the same sputum (HS) were examined by three experienced microbiologists. Aproportion of the slides prepared by each method

G. W Smith; R. R White; E. R Ridgeway; J. E Corkill

2000-01-01

235

Data reproducibility in fluorescence image analysis  

Microsoft Academic Search

Fluorescence image analysis provides quantitative data on fluorescence in situ hybridiza-tion signals (FISH), immunofluorescence labelings, Green Fluorescent Protein (GFP) expression and microarrays. It is a valuable tool for decision making in the fields of biology and medicine. The aim of this study was to evaluate the reproducibility of fluorescence intensity measurements and standardization when acquisitions are performed under various but

Catherine Souchier; Christine Brisson; Bernadette Batteux; Michel Robert-Nicoud; Paul-André Bryon

2004-01-01

236

Explicit recursivity into reproducing kernel Hilbert spaces  

Microsoft Academic Search

Thispaper presentsa methodologyto developrecursivefilters in reproducing kernel Hilbert spaces (RKHS). Unlike previous approaches that exploit the kernel trick on filtered and then mapped samples, we explicitly define model recursivity in the Hilbert space. The method exploits some properties of functionalanalysis and recursive computation of dot products without the need of pre-imaging. We illustrate the feasibility of the methodology in the

Devis Tuia; Gustavo Camps-Valls; Manel Martinez-Ramon

2011-01-01

237

Natural Disasters: Earth Science Readings. Reproducibles.  

ERIC Educational Resources Information Center

|Natural Disasters is a reproducible teacher book that explains what scientists believe to be the causes of a variety of natural disasters and suggests steps that teachers and students can take to be better prepared in the event of a natural disaster. It contains both student and teacher sections. Teacher sections include vocabulary, an answer…

Lobb, Nancy

238

Reproducing Groups for the Metaplectic Representation  

Microsoft Academic Search

We consider the (extended) metaplectic representation of the semidirect product G of the symplectic group and the Heisenberg group. By looking at the standard resolution of the identity formula and inspired by previous work [5], [13], [4], we introduce the notion of admissible (reproducing) subgroup of G via the Wigner distribution. We prove some features of admissible groups and then

E. Cordero; F. DE MARI; K. Nowak; A. Tabacco

239

Europe Today: An Atlas of Reproducible Pages.  

ERIC Educational Resources Information Center

Illustrative black and white maps, tables, and graphs designed for clear reproducibility depict Europe's size, population, resources, commodities, trade, cities, schooling, jobs, energy, industry, demographic statistics, food, and agriculture. Also included are 33 United States Department of State individual country maps. This volume is intended…

World Eagle, Inc., Wellesley, MA.

240

Reproducing color images using custom inks  

Microsoft Academic Search

We investigate the general problem of reproducing color images on an offset press using custom inks in any combination and number. While this problem has been explored previously for the case of two inks, there are a number of new mathematical and algorithmic chal- lenges that arise as the number of inks increases. These challenges include more complex gamut mapping

Eric J. Stollnitz; Victor Ostromoukhov; David H. Salesin

1998-01-01

241

Extreme ultraviolet spectra from highly charged gadolinium and neodymium ions in the Large Helical Device and laser produced plasmas  

NASA Astrophysics Data System (ADS)

We have observed extreme ultraviolet spectra from highly charged gadolinium (Gd) and neodymium (Nd) ions produced in two different types of light sources for comparative studies. Only broad quasicontinuum feature arising from unresolved transition array was observed in high-density laser produced plasmas of pure/diluted Gd and Nd targets at the University College Dublin, and the spectral feature largely depends on electron temperature in optically thin plasmas produced in the Large Helical Device at the National Institute for Fusion Science. The difference in spectral feature among a number of spectra can be qualitatively interpreted by considering dominant ion stages and opacity effects in the plasmas.

Suzuki, C.; Koike, F.; Murakami, I.; Tamura, N.; Sudo, S.; O'Gorman, C.; Li, B.; Harte, C. S.; Donnelly, T.; O'Sullivan, G.

2013-09-01

242

Improving produce safety by stabilizing chlorine in washing solutions with high organic loads  

Technology Transfer Automated Retrieval System (TEKTRAN)

The need for technologies to protect our nation’s food supply and support sustained growth of the produce industry has never been more urgent. The produce industry currently faces a major potential food safety problem, since the chlorine needed to prevent pathogen survival is depleted during commer...

243

Swine Intestinal Tract Harbors a High Diversity of Butyrate-Producing Bacteria  

Technology Transfer Automated Retrieval System (TEKTRAN)

Butyrate is a preferred energy source of human colonic epithelial cells, and changes in the communities of butyrate-producing bacteria have been associated with adverse health. We hypothesize that in swine, like in humans, butyrate-producing bacteria contribute to a healthy intestinal ecosystem. T...

244

Feeding management and characteristics of rations for high-producing dairy cows in freestall herds.  

PubMed

The objectives of this cross-sectional observational study were to 1) describe the feeding management and characteristics of rations for high-producing Holstein cows housed in freestall barns in Minnesota, 2) evaluate ration change over time, and 3) investigate herd-level risk factors for ration change. Each of 50 randomly selected freestall dairy herds was visited once during the study. Samples of TMR were collected from the high-production group feed bunk to represent the initial ration as delivered to the cows, 3 additional samples were collected every 2 to 3h after feed delivery, and the accumulated orts were cleaned out of the feed bunk. Feeding management practices and TMR formulation were also collected at the time of visit. Seventy percent of herds fed once daily, 22% fed twice daily, and 8% fed 3 times daily. Frequency of feed push-up was 5.4+/-2.3 times daily. Linear feed bunk space per cow was 0.45+/-0.11m. Sixty-two percent of the farms had 3-row pens and 38% had 2-row pens. Linear feed bunk space per cow was greater in 2-row pens (0.56 m/cow) than in 3-row pens (0.39 m/cow). Post and rail was the most common type of feed barrier; it was used by 60% of the herds. Headlocks were used by 28% of the herds, combination of post and rail with headlocks was used by 8%, and diagonal bars were used by 4%. Water trough linear space was 4.6+/-2.1 cm/cow. Estimated dry matter intake was 24.3 kg/cow per day. The forage content of the formulated ration was 52% of the ration DM, and corn silage was the most commonly used forage. The NDF content of the analyzed ration was greater than the NDF content of the formulated ration (30.6 and 29.8%, respectively). In contrast, the CP content was lower (17.5 and 17.9%, respectively). Some feeding management practices (e.g., feeding frequency) were associated with ration NDF content change over time. This association may be minimized by implementing ration and management changes. PMID:20105555

Endres, M I; Espejo, L A

2010-02-01

245

Methods for producing high titre vectors and compositions used in such methods  

US Patent & Trademark Office Database

A method for producing viral vectors is described using packaging and producer cell lines is described. The producer cell comprises: (i) a first nucleotide sequence (NS) encoding a toxic viral envelope protein operably linked to a promoter; wherein the promoter is operably linked to at least one copy of a TRE; (ii) a second NS wherein the second NS comprises a sequence encoding a tetracycline modulator; (iii) a third NS encoding a retrovirus nucleocapsid protein; and (iv) a fourth NS comprising a retroviral sequence capable of being encapsidated in the nucleocapsid protein such that the retroviral vector particle titre obtainable from the producer cell is regulatable by tetracycline and an initial stimulus with sodium butyrate or functional analogues thereof.

Olsen; John C. (Chapel Hill, NC); Mitrophanous; Kyriacos Andreou (Oxford, GB); Rohll; Jonathan (San Diego, CA); Kingsman; Alan John (Oxford, GB); Ellard; Fiona Margaret (Berkshire, GB)

2005-11-29

246

Viability of seed produced on highly sodic coal-mine spoils. Forest Service research note  

SciTech Connect

An adapted plant species must not only grow on a particular site, but also produce viable seeds capable of germination and establishment on the site. Ten species of rangeland grasses had been successfully used to revegetate sodic mine spoils at the Decker Coal Mine in southeastern Montana. However, the effect of the sodic spoils on seed viability, and hence the potential for regeneration, was unknown. Seeds produced by these plants were tested for viability and germination.

Richardson, B.Z.; McDonough, W.T.; Farmer, E.E.

1984-10-01

247

Hydrogen reduction of copper bleed solution from an Indian copper smelter for producing high purity copper powders  

Microsoft Academic Search

A bench scale investigation on the hydrogen reduction of a highly acidic copper bleed solution to produce high purity copper powder is discussed in this paper. A titanium lined autoclave of 1 L capacity was used for this study. The parameters optimized on the bench scale were validated by performing hydrogen reduction of copper in a larger autoclave. Effect of various

Archana Agrawal; Sarita Kumari; D. Bagchi; V. Kumar; B. D. Pandey

2006-01-01

248

Effect of Electrode for Producing the Highly Charged Heavy Ions from RIKEN 18 GHz Electron Cyclotron Resonance Ion Source  

Microsoft Academic Search

We successfully produced the intense beam of highly charged Kr ions using an electrode. Under the pulsed mode operation, we found that the depth of the plasma potential dip strongly depends on the duration of the microwave and takes about 40 ms to reach the equilibrium state. Taking these results into account, we compared the beam intensities of highly charged

Tetsuro Kurita; Takahide Nakagawa; Masanori Kidera; Yoshitoshi Miyazawa; Masatake Hemmi; Toshiya Chiba; Naohito Inabe; Masayuki Kase; Tadashi Kageyama; Osamu Kamigaito; Akira Goto; Yasushige Yano

1999-01-01

249

Reproducibility of technetium-99m ethylenedicysteine clearance  

Microsoft Academic Search

.   It has been shown that technetium-99m ethylenedicysteine (99mTc-EC) clearance displays a strong correlation with orthoiodohippurate clearance and that it is possible to estimate effective\\u000a renal plasma flow from 99mTc-EC clearance. However, in routine practice, when monitoring renal function of patients by clearance determinations it is\\u000a imperative to test the reproducibility of the clearance technique in order to decide whether

Levent Kabasakal; Metin Halaç; Ebru Alkan; Nihat Özçelik; I. lhami Uslu

1999-01-01

250

Data Identifiers and Citations Enable Reproducible Science  

NASA Astrophysics Data System (ADS)

Modern science often involves data processing with tremendous volumes of data. Keeping track of that data has been a growing challenge for data center. Researchers who access and use that data don't always reference and cite their data sources adequately for consumers of their research to follow their methodology or reproduce their analyses or experiments. Recent research has led to recommendations for good identifiers and citations that can help address this problem. This paper will describe some of the best practices in data identifiers, reference and citation. Using a simplified example scenario based on a long term remote sensing satellite mission, it will explore issues in identifying dynamic data sets and the importance of good data citations for reproducibility. It will describe the difference between granule and collection level identifiers, using UUIDs and DOIs to illustrate some recommendations for developing identifiers and assigning them during data processing. As data processors create data products, the provenance of the input products and precise steps that led to their creation are recorded and published for users of the data to see. As researchers access the data from an archive, they can use the provenance to help understand the genesis of the data, which could have effects on their usage of the data. By citing the data on publishing their research, others can retrieve the precise data used in their research and reproduce the analyses and experiments to confirm the results. Describing the experiment to a sufficient extent to reproduce the research enforces a formal approach that lends credibility to the results, and ultimately, to the policies of decision makers depending on that research.

Tilmes, C.

2011-12-01

251

Development of a high-titer retrovirus producer cell line capable of gene transfer into rhesus monkey hematopoietic stem cells  

SciTech Connect

Retroviral-mediated gene transfer into primitive hematopoietic cells has been difficult to achieve in large-animal models. The authors have developed an amphotropic producer clone that generates >10{sup 10} recombinant retroviral particles (colony-forming units) per ml of culture medium. Autologous rhesus monkey bone marrow cells were cocultured with either high or low titer producer clones for 4-6 days and reinfused into sublethally irradiated animals. The proviral genome was detected in blood and bone-marrow cells from all three animals reconstituted with cells cocultured with the high-titer producer cells. In contrast, three animals reconstituted with bone marrow cocultured with the low-titer producer clone exhibited no evidence of gene transfer.

Bodine, D.M.; McDonagh, K.T.; Brandt, S.J.; Ney, P.A.; Agricola, B.; Byrne, E.; Nienhuis, A.W. (National Institutes of Health, Bethesda, MD (USA))

1990-05-01

252

Photoelectrocatalytic decontamination of oilfield produced wastewater containing refractory organic pollutants in the presence of high concentration of chloride ions  

Microsoft Academic Search

The feasibility study of the application of the photoelectrocatalytic decontamination of high saline produced water containing refractory organic pollutants was investigated in the slurry photoelectrocatalytic reactor with nanometer TiO2 particle prepared with sol–gel method using the acetic acid as hydrolytic catalyst. The efficiency of the photoelectrocatalytic decontamination of produced water was determined with both COD removal from the tested wastewater

Guiying Li; Taicheng An; Jiaxin Chen; Guoying Sheng; Jiamo Fu; Fanzhong Chen; Shanqing Zhang; Huijun Zhao

2006-01-01

253

The visibility of UV and visible lines of highly ionized carbon in spectra of laser-produced plasmas  

Microsoft Academic Search

A complete UV–VIS spectrum of laser-produced carbon plasmas, produced by a 5J, 15ns ruby laser was recorded and searched for spectral lines of highly ionized carbon (C V and C VI lines). Several C V and C VI lines are observed, but are weak, compared to other carbon lines. Still, some C V lines are distinctive enough to be used

Ž. Andrei?; D. Gracin; L. Aschke; H.-J. Kunze

2001-01-01

254

High repetition rate laser produced soft x-ray source for ultrafast x-ray absorption near edge structure measurements  

Microsoft Academic Search

Recent progress in high intensity ultrafast laser systems provides the opportunity to produce laser plasma x-ray sources exhibiting broad spectrum and high average x-ray flux that are well adapted to x-ray absorption measurements. In this paper, the development of a laser based x-ray absorption near edge structure (XANES) beamline exhibiting high repetition rate by using the Advanced Laser Light Source

S. Fourmaux; L. Lecherbourg; M. Harmand; M. Servol; J. C. Kieffer

2007-01-01

255

Direct observation of microscopic inhomogeneities in high-Tc superconductors using energy-dispersive diffraction of synchrotron-produced xrays  

Microsoft Academic Search

Evidence of micron-sized structural inhomogeneities in several high transition temperature (Tc) superconductors is presented. By illuminating samples with high energy, highly collimated x rays produced on a synchrotron wiggler, small changes in the lattice were detected over a spatial scale as small as 10 micrometer. In the YBa2Cu3O7-(delta ) crystals, these changes are interpreted as evidence of variations in the

Earl F. Skelton; Syen B. Qadri; Michael S. Osofsky; A. R. Drews; P. R. Broussard; J. Z. Hu; L. W. Finger; Terrell A. Vanderah; D. Kaiser; J. L. Peng; Steven M. Anlage; Richard L. Greene; John Giapintzakis

1995-01-01

256

Simvastatin and preparation of polyunsaturated phospholipids produce similar changes in the phospholipid composition of high-density lipoproteins during hypercholesterolemia.  

PubMed

We studied the phospholipid composition of high-density lipoproteins in patients with coronary heart disease and hypercholesterolemia treated with simvastatin (Zocor, inhibitor of the key enzyme of cholesterol synthesis) and preparation of polyunsaturated phospholipids (lipostabil forte). Simvastatin produced a hypolipidemic effect and modulates the phospholipid composition of high-density lipoproteins (similarly to lipostabil forte). These changes contribute to functional activity of high-density lipoproteins in the reverse cholesterol transport. PMID:16027809

Ozerova, I N; Akhmedzhanov, N M; Perova, N V; Paramonova, I V

2005-02-01

257

LETTER TO THE EDITOR: Charge-exchange-induced formation of hollow atoms in high-intensity laser-produced plasmas  

Microsoft Academic Search

For the first time registration of high-resolution soft x-ray emission and atomic data calculations of hollow-atom dielectronic satellite spectra of highly charged nitrogen have been performed. Double-electron charge-exchange processes from excited states are proposed for the formation of autoionizing levels 0953-4075\\/32\\/5\\/031\\/img12 in high-intensity laser-produced plasmas, when field-ionized ions penetrate into the residual gas. Good agreement is found between theory and

F. B. Rosmej; A. Ya Faenov; T. A. Pikuz; A. I. Magunov; I. Yu Skobelev; T. Auguste; P. D'Oliveira; S. Hulin; P. Monot; N. E. Andreev; M. V. Chegotov; M. E. Veisman

1999-01-01

258

Breeding of high-pyruvate-producing Torulopsis glabrata with acquired reduced pyruvate decarboxylase  

Microsoft Academic Search

An efficient method for isolation of pyruvate-producing mutants of Torulopsis glabrata IFO 0005 was established. On mutagenesis of the parent strain, mutants requiring acetate for complete growth were isolated. The acetate-leaky auxotrophic mutants demonstrated higher fermentative yields of pyruvate from glucose than the parent strain. Thus, the pyruvate decarboxylase (PDC) activity of mutants requiring acetate for complete growth was lower

Reiko Miyata; Tetsu Yonehara

1999-01-01

259

Comparison of quark and gluon jets produced in high-energy e+e- annihilations  

Microsoft Academic Search

Three-jet events produced in e+e- annihilations are used to provide comparisons between quark and gluon jets. Differences between quark-induced and gluon-induced jets are observed. Quark jets tend to have a more tightly collimated structure than gluon jets, which is reflected in the concentration of a larger fraction of the jet's energy near the jet axis.

Y. K. Kim; P. Auchincloss; D. Blanis; A. Bodek; H. Budd; S. Eno; C. A. Fry; H. Harada; Y. H. Ho; T. Kumita; T. Mori; S. L. Olsen; N. M. Shaw; A. Sill; E. H. Thorndike; K. Ueno; H. W. Zheng; R. Imlay; P. Kirk; J. Lim; R. R. McNeil; W. Metcalf; S. S. Myung; C. P. Cheng; P. Gu; J. Li; Y. K. Li; Z. P. Mao; Y. T. Xu; Y. C. Zhu; A. Abashian; K. Gotow; K. P. Hu; E. H. Low; M. E. Mattson; L. Piilonen; K. L. Sterner; S. Lusin; C. Rosenfeld; A. T. Wang; S. Wilson; M. Frautschi; H. Kagan; R. Kass; C. G. Trahern; R. E. Breedon; G. N. Kim; Winston Ko; R. L. Lander; K. Maeshima; R. L. Malchow; J. R. Smith; D. Stuart; M. C. Williams; K. Abe; Y. Fujii; Y. Higashi; S. K. Kim; Y. Kurihara; A. Maki; T. Nozaki; T. Omori; H. Sagawa; Y. Sakai; Y. Sugimoto; Y. Takaiwa; S. Terada; R. Walker; F. Kajino; D. Perticone; R. Poling; T. Thomas; Y. Ishi; K. Miyano; H. Miyata; T. Sasaki; Y. Yamashita; A. Bacala; I. H. Park; F. Sannes; S. Schnetzer; R. Stone; J. Vinson; H. Itoh; S. Kobayashi; A. Murakami; K. Toyoshima; J. S. Kang; H. J. Kim; M. H. Lee; D. H. Han; E. J. Kim; D. Son; T. Kojima; S. Matsumoto; R. Tanaka; Y. Yamagishi; T. Yasuda; H. Yokota; T. Ishizuka; K. Ohta

1989-01-01

260

Producing Success: The Culture of Personal Advancement in an American High School  

ERIC Educational Resources Information Center

|Middle- and upper-middle-class students continue to outpace those from less privileged backgrounds. Most attempts to redress this inequality focus on the issue of access to financial resources, but as "Producing Success" makes clear, the problem goes beyond mere economics. In this eye-opening study, Peter Demerath examines a typical suburban…

Demerath, Peter

2009-01-01

261

Influence of laser satellite transitions on spectroscopy of high-intensity laser-produced plasmas  

Microsoft Academic Search

The oscillating electromagnetic field of an intense laser pulse can significantly affect the emission properties of ions in a plasma. For sufficiently intense laser fields, induced second order processes produce discrete radiative transitions. In addition, these induced radiative processes alter the level population kinetics, and the spectrum of spontaneous transitions. We discuss the effects of these processes on the n

A. L. Osterheld; B. K. F. Young; J. Dunn; R. E. Stewart; I. Yu. Skobelev; A. Ya. Faenov; A. I. Magunov

1997-01-01

262

Producing Success: The Culture of Personal Advancement in an American High School  

ERIC Educational Resources Information Center

Middle- and upper-middle-class students continue to outpace those from less privileged backgrounds. Most attempts to redress this inequality focus on the issue of access to financial resources, but as "Producing Success" makes clear, the problem goes beyond mere economics. In this eye-opening study, Peter Demerath examines a typical suburban…

Demerath, Peter

2009-01-01

263

GMR Biosensor Arrays: Correction Techniques for Reproducibility and Enhanced Sensitivity  

PubMed Central

Giant magnetoresistive biosensors possess great potential in biomedical applications for quantitatively detecting magnetically tagged biomolecules. Magnetic sensing does not suffer from the high background levels found in optical sensing modalities such as the enzyme linked immunosorbent assay translating into a technology with higher sensitivity. However, to reveal the full potential of these sensors and compensate for non-idealities such as temperature dependence, digital correction and calibration techniques are not only useful but imperative. Using these calibration techniques to correct for process variations and dynamic changes in the sensing environment (such as temperature and magnetic field), we are able to obtain extremely sensitive and, more importantly, reproducible results for quantifiable biomolecular reorganization. The reproducibility of the system was improved by over 3× using digital correction techniques and the sensors are made temperature independent by using a novel background correction technique.

Hall, D. A.; Gaster, R. S.; Osterfeld, S. J.; Murmann, B.; Wang, S. X.

2010-01-01

264

Nano-grained pure copper with high-strength and high-conductivity produced by equal channel angular rolling process  

Microsoft Academic Search

Equal channel angular rolling, based on the equal channel angular pressing, is a severe plastic deformation process which can develop the grains below 1?m in diameter. Microstructure, mechanical properties and electrical conductivity of commercial pure copper strips processed by equal channel angular rolling were investigated. Scanning electron microscopic micrographs of the strips produced by ten passes of equal channel angular

Asiyeh Habibi; Mostafa Ketabchi; Mohammad Eskandarzadeh

2011-01-01

265

On the use of ICE\\/SAT Lidar Space-Born Observations to Evaluate the Ability of MM5 Meso-Scale Model to Reproduce High Altitude Clouds Over Europe in Fall  

Microsoft Academic Search

The Ozone Monitoring Instrument (OMI) on EOS\\/Aura offers unprecedented spatial and spectral resolution, coupled with global coverage, for space-based UV measurements of sulfur dioxide (SO2). Publicly released SO2 pollution data are processed with the Band Residual Difference (BRD) algorithm that uses calibrated residuals at SO2 absorption band centers produced by the NASA operational ozone algorithm (OMTO3). By using optimum wavelengths

N. A. Krotkov; P. Bhartia; K. Yang; S. A. Carn; A. J. Krueger; R. R. Dickerson; J. Hains; C. Li; Z. Li; L. Marufu; J. Stehr; P. F. Levelt

2005-01-01

266

Thermal damage produced by high-irradiance continuous wave CO2 laser cutting of tissue.  

PubMed

Thermal damage produced by continuous wave (cw) CO2 laser ablation of tissue in vitro was measured for irradiances ranging from 360 W/cm2 to 740 kW/cm2 in order to investigate the extent to which ablative cooling can limit tissue damage. Damage zones thinner than 100 microns were readily produced using single pulses to cut guinea pig skin as well as bovine cornea, aorta, and myocardium. Multiple pulses can lead to increased damage. However, a systematic decrease in damage with irradiance, predicted theoretically by an evaporation model of ablation, was not observed. The damage-zone thickness was approximately constant around the periphery of the cut, consistent with the existence of a liquid layer which stores heat and leads to tissue damage, and with a model of damage and ablation recently proposed by Zweig et al. PMID:2308468

Schomacker, K T; Walsh, J T; Flotte, T J; Deutsch, T F

1990-01-01

267

High quality electron beam produced by laser: A new tool for science  

NASA Astrophysics Data System (ADS)

The use of ultra short laser pulses delivered by powerful laser systems has permitted the emergence of new approaches for generating energetic particle beams. By focusing these laser pulses onto matter, extremely large electric fields can be generated, reaching the TV/m level well in excess than those produced by conventional accelerators. As a result, the distance over which particles extracted from the target can be accelerated to hundreds of MeV is reduced to distances on the order of millimetres. These laser-produced electron beams have a number of interesting properties and could lead themselves to applications in many fields, including medicine (radiotherapy), radiobiology (short-time-scale, low dose irradiation), chemistry (radiolysis), non-destructive material inspection by radiography, and accelerator physics.

Malka, V.; Faure, J.; Glinec, Y.; Lifschitz, A. F.

2006-10-01

268

Thermal damage produced by high-irradiance continuous wave CO sub 2 laser cutting of tissue  

SciTech Connect

Thermal damage produced by continuous wave (cw) CO{sub 2} laser ablation of tissue in vitro was measured for irradiances ranging from 360 W/cm{sup 2} to 740 kW/cm{sup 2} in order to investigate the extent to which ablative cooling can limit tissue damage. Damage zones thinner than 100 microns were readily produced using single pulses to cut guinea pig skin as well as bovine cornea, aorta, and myocardium. Multiple pulses can lead to increased damage. However, a systematic decrease in damage with irradiance, predicted theoretically by an evaporation model of ablation, was not observed. The damage-zone thickness was approximately constant around the periphery of the cut, consistent with the existence of a liquid layer which stores heat and leads to tissue damage, and with a model of damage and ablation recently proposed by Zweig et al.

Schomacker, K.T.; Walsh, J.T. Jr.; Flotte, T.J.; Deutsch, T.F. (Massachusetts General Hospital, Boston (USA))

1990-01-01

269

Universality of multifragmentation of residual nuclei produced in high-energies nucleus-nucleus interactions  

Microsoft Academic Search

Experimental data on the multifragmentation of residual nuclei produced in the krypton interactions with photoemulsion nuclei\\u000a at 0.9 GeV per projectile nucleon are presented and compared with similar data on fragmentation from experiments where gold\\u000a nuclei of energy 10.7 GeV per nucleon appear as projectiles. It is shown for the first time that there exist two modes of\\u000a nuclear multifragmentation,

A. Abd-Elhafiez; V. Sh. Navotny; V. V. Uzhinskii; G. I. Orlova; M. M. Chernyavski

2001-01-01

270

A low-cost, high-yield fabrication method for producing optimized biomimetic dry adhesives  

Microsoft Academic Search

We present a low-cost, large-scale method of fabricating biomimetic dry adhesives. This process is useful because it uses all photosensitive polymers with minimum fabrication costs or complexity to produce molds for silicone-based dry adhesives. A thick-film lift-off process is used to define molds using AZ 9260 photoresist, with a slow acting, deep UV sensitive material, PMGI, used as both an

D. Sameoto; C. Menon

2009-01-01

271

Effect on Dietary Protein on High-Producing Dairy Cows in Early Lactation1  

Microsoft Academic Search

Thirty Holstein cows capable of producing at least 30 kg of milk per day were assigned to one of three com- pletely mixed rations containing corn silage, chopped alfalfa hay, and concen- trate mixture. These rations differed only in crude protein content (12.7, 16.3, or 19.3% dry matter). All cows were fed their assigned ration continuously for 90 days beginning

Donald W. Claypool; M. C. Pangboan; H. P. Adams

1980-01-01

272

Linking Quality Assurance to Performance Improvement to Produce a High Reliability Organization  

SciTech Connect

Three basic change management models are currently used in healthcare to produce and sustain quality improvement. We have presented the context to determine where any particular organization stands within these paradigms. We also have introduced a change-management tool used to assess, plan, and monitor leadership effort and commitment to quality improvement and culture change activities, tracked as 'momentum for change.' This 'momentum' is measured at eight discrete levels, from recognizing a performance gap to officially implementing changes intended to improve quality.

Silvey, Andrea B. [Quality Improvement, Health Services Advisory Group, Phoenix, AZ (United States); Warrick, Louise H. [Healthcare Consultant, Tucson, AZ (United States)], E-mail: lwarrick@cox.net

2008-05-01

273

A low-cost, high-yield fabrication method for producing optimized biomimetic dry adhesives  

NASA Astrophysics Data System (ADS)

We present a low-cost, large-scale method of fabricating biomimetic dry adhesives. This process is useful because it uses all photosensitive polymers with minimum fabrication costs or complexity to produce molds for silicone-based dry adhesives. A thick-film lift-off process is used to define molds using AZ 9260 photoresist, with a slow acting, deep UV sensitive material, PMGI, used as both an adhesion promoter for the AZ 9260 photoresist and as an undercutting material to produce mushroom-shaped fibers. The benefits to this process are ease of fabrication, wide range of potential layer thicknesses, no special surface treatment requirements to demold silicone adhesives and easy stripping of the full mold if process failure does occur. Sylgard® 184 silicone is used to cast full sheets of biomimetic dry adhesives off 4" diameter wafers, and different fiber geometries are tested for normal adhesion properties. Additionally, failure modes of the adhesive during fabrication are noted and strategies for avoiding these failures are discussed. We use this fabrication method to produce different fiber geometries with varying cap diameters and test them for normal adhesion strengths. The results indicate that the cap diameters relative to post diameters for mushroom-shaped fibers dominate the adhesion properties.

Sameoto, D.; Menon, C.

2009-11-01

274

Process for producing a clean hydrocarbon fuel from high calcium coal  

SciTech Connect

A method is described for substantially reducing the amount of at least one insoluble fluoride-forming species selected from the group consisting of Group IA species and Group IIA species. The species is present in a coal feed material comprising: forming a slurry of a coal feed; a fluoride acid in an amount to produce a first molar concentration of free-fluoride-ions; at least one fluoride-complexing species, the total of all fluoride-complexing species in the slurry being present in an amount to produce a second molar concentration, the second molar concentration being at least equal to that amount such that the ratio of the first molar concentration to the second molar concentration is substantially equal to the stoichiometric ratio of fluoride in at least one tightly-bound complexion so as to from tightly-bound complexions with substantially all free-fluoride ions in the slurry to produce a leached coal product and a spent leach liquor; and separating the leached coal product from the spent leach liquor.

Kindig, J.K.

1988-06-28

275

An improved reproducing kernel particle method for nearly incompressible finite elasticity  

Microsoft Academic Search

The previously developed reproducing kernel particle method (RKPM) employs a high-order quadrature rule for desired domain integration accuracy. This leads to an over-constrained condition in the limit of incompressibility, and volumetric locking and pressure oscillation were encountered. The employment of a large support size in the reproducing kernel shape function increases the dependency in the discrete constraint equations at quadrature

Jiun-Shyan Chen; Sangpil Yoon; Hui-Ping Wang; Jiun-Shyan Chen

2000-01-01

276

Generation of fluxes of highly charged heavy ions from a picosecond laser-produced plasma  

Microsoft Academic Search

The results of the investigations of ion emission from targets of medium and high atomic numbers irradiated by 1 ps laser pulse of intensity up to 5×1016 W\\/cm2 are presented. The generation of high energy (up to 1 MeV) highly charged heavy ions (Ta+38, Au+33), as well as Ar-like Ag ions and fully striped Al ions is demonstrated. Some properties

J. Badziak; P. Parys; A. B. Vankov; J. Wolowski; E. Woryna

2001-01-01

277

Mineral-produced high-pressure striae and clay polish: Key evidence for nonballistic transport of ejecta from Ries crater  

USGS Publications Warehouse

Recently discovered mineral-produced, deeply incised striae and mirror-like polish on broken surfaces of limestone fragments from the sedimentary ejecta of the Ries impact crater of southern Germany are described. The striae and polish were produced under high confining pressures during high-velocity nonballistic transport of the ejecta mass within the time span of the cratering event (measured in terms of seconds). The striae on these fragments were produced by scouring by small mineral grains embedded in the surrounding clay matrix, and the polish was formed under the same condition, by movements of relatively fragment-free clay against the fragment surfaces. The occurrence of these striae and polish is key evidence for estimating the distribution and determining the relative importance of nonballistic and ballistic transport of ejecta from the shallow Ries stony meteorite impact crater.

Chao, E. C. T.

1976-01-01

278

High temperature wear behavior of aluminum oxide layers produced by AC micro arc oxidation  

Microsoft Academic Search

Aluminum alloys are becoming increasingly important, especially in the automotive and aerospace industries. However, these materials tend to have poor wear resistance at atmospheric and high temperature conditions. Aluminum oxide layers are potentially very effective in developing hard, wear-resistant surfaces. The aim of present study was to evaluate the high temperature wear behavior of aluminum oxide layers at different temperatures

E. Arslan; Y. Totik; E. E. Demirci; Y. Vangolu; A. Alsaran; I. Efeoglu

2009-01-01

279

Properties of Laser-Produced Highly Charged Heavy Ions for Direct Injection Scheme  

Microsoft Academic Search

To accelerate highly charged intense ion beam, we have developed the Direct Plasma Injection Scheme (DPIS) with laser ion source. In this scheme an ion beam from a laser ion source is injected directly to a RFQ linac without a low energy beam transport (LEBT) line and the beam loss in the LEBT can be avoided. We achieved high current

K. Sakakibara; T. Hattori; N. Hayashizaki; T. Ito; H. Kashiwagi; M. Okamura

2005-01-01

280

Plasma channels produced by a laser-triggered high-voltage discharge  

NASA Astrophysics Data System (ADS)

A plasma waveguide scheme for high-intensity laser guiding with densities and lengths suitable for laser-plasma particle accelerators is presented. This scheme uses a laser-triggered high-voltage discharge, presents negligible jitter, allows full access to the plasma, and can be scaled to large distances. Experimental results showing the feasibility of this scheme are presented.

Lopes, N. C.; Figueira, G.; Silva, L. O.; Dias, J. M.; Fonseca, R.; Cardoso, L.; Russo, C.; Carias, C.; Mendes, G.; Vieira, J.; Mendonça, J. T.

2003-09-01

281

Amplification of the isopenicillin N synthetase gene in a strain of Penicillium chrysogenum producing high levels of penicillin  

Microsoft Academic Search

The isopenicillin N synthetase (IPNS) gene has been isolated from wild-type Penicillium chrysogenum and used as a probe to detect the equivalent gene on Southern blots of genomic DNA from a mutant producing high levels of penicillin. The IPNS gene in this strain is contained within a region of DNA of wild-type restriction pattern that extends for at least 39

David J. Smith; John H. Bull; Jeffrey Edwards; Geoffrey Turner

1989-01-01

282

Fish Offal Recycling by the Black Soldier Fly Produces a Foodstuff High in Omega3 Fatty Acids  

Microsoft Academic Search

The black soldier fly, Hermetia illucens, has the potential to reduce animal waste on livestock facilities and produce an animal-grade feedstuff high in protein and fat. The lipid content of insects is largely dependent on their diet. Data from this study suggest that black soldier fly prepupae incorporate a-linolenic acid (ALA), eicosapen- taenoic acid (EPA), and docosahexaenoic acid (DHA) when

Sophie St-Hilaire; Katie Cranfill; Mark A. McGuire; Erin E. Mosley; Jeffery K. Tomberlin; Larry Newton; Wendy Sealey; Craig Sheppard; Stephen Irving

2007-01-01

283

High-resolution ultrasonic monitoring of cellular differentiation in an ex vivo produced oral mucosal equivalent (EVPOME)  

Microsoft Academic Search

Background, Motivation and Objective This study examines the use of high-resolution ultrasound to monitor an ex vivo produced oral mucosal equivalent (EVPOME) as it develops from oral keratinocytes being seeded on a dermal cadaveric scaffold, with surface variations, into a stratified uniform cellular layer. Ultrasonic profilometry should be able to detect filling and smoothing of surface irregularities as seeded cells

F. Winterroth; S. J. Hollister; K. W. Hollman; S. E. Feinberg; J. B. Fowlkes; S. Kuo; K. Izumi

2009-01-01

284

Secondary ions produced from condensed rare gas targets under highly charged MeV\\/amu heavy ion bombardment  

Microsoft Academic Search

Secondary ions produced from condensed rare gas targets are observed under MeV\\/amu, highly charged, heavy ion impact. The intensities of the observed cluster ions decrease smoothly as the cluster sizes become large but show some discontinuities at particular sizes of cluster ions. This seems to be closely related to the stabilities of cluster ion structures. It is also noted that

H. Tawara; T. Tonuma; H. Kumagai; T. Matsuo

1994-01-01

285

On the origin of reproducible sequential activity in neural circuits  

NASA Astrophysics Data System (ADS)

Robustness and reproducibility of sequential spatio-temporal responses is an essential feature of many neural circuits in sensory and motor systems of animals. The most common mathematical images of dynamical regimes in neural systems are fixed points, limit cycles, chaotic attractors, and continuous attractors (attractive manifolds of neutrally stable fixed points). These are not suitable for the description of reproducible transient sequential neural dynamics. In this paper we present the concept of a stable heteroclinic sequence (SHS), which is not an attractor. SHS opens the way for understanding and modeling of transient sequential activity in neural circuits. We show that this new mathematical object can be used to describe robust and reproducible sequential neural dynamics. Using the framework of a generalized high-dimensional Lotka-Volterra model, that describes the dynamics of firing rates in an inhibitory network, we present analytical results on the existence of the SHS in the phase space of the network. With the help of numerical simulations we confirm its robustness in presence of noise in spite of the transient nature of the corresponding trajectories. Finally, by referring to several recent neurobiological experiments, we discuss possible applications of this new concept to several problems in neuroscience.

Afraimovich, V. S.; Zhigulin, V. P.; Rabinovich, M. I.

2004-12-01

286

Process for producing silicon nitride based articles of high fracture toughness and strength  

DOEpatents

A process for producing a silicon nitride-based article of improved fracture toughness and strength is disclosed. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12 m[sup 2]/g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. Optionally, the mixture may be blended with a binder and injection molded to form a green body, which then may be densified by, for example, hot isostatic pressing.

Huckabee, M.; Buljan, S.T.; Neil, J.T.

1991-09-10

287

Process for producing silicon nitride based articles of high fracture toughness and strength  

DOEpatents

A process for producing a silicon nitride-based article of improved fracture toughness and strength. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12 m.sup.2 /g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. Optionally, the mixture may be blended with a binder and injection molded to form a green body, which then may be densified by, for example, hot isostatic pressing.

Huckabee, Marvin (Marlboro, MA); Buljan, Sergej-Tomislav (Acton, MA); Neil, Jeffrey T. (Acton, MA)

1991-01-01

288

Evaluation of the high temperature electrolysis of steam to produce hydrogen  

Microsoft Academic Search

A very high temperature gas-cooled reactor (VHTR) can be effectively used for hydrogen production through several CO2-free alternative technologies, such as the Sulfur–Iodine (SI) cycle, the high temperature electrolysis of steam (HTES), and others. In our current study, the electrochemical thermodynamic properties and the overall thermal efficiency of the VHTR-assisted hydrogen production system by using the HTES technology have been

Youngjoon Shin; Wonseok Park; Jonghwa Chang

2007-01-01

289

High-resolution mass spectrometric analysis of secondary organic aerosol produced by ozonation of limonene  

Microsoft Academic Search

Chemical composition of secondary organic aerosol (SOA) formed from the ozone-initiated oxidation of limonene is characterized by high-resolution electrospray ionization mass spectrometry in both positive and negative ion modes. The mass spectra reveal a large number of both monomeric (m\\/z o 300) and oligomeric (m\\/z 4 300) condensed products of oxidation. A combination of high resolving power (m\\/Dm B 60

Maggie L. Walser; Yury Dessiaterik; Julia Laskin; Alexander Laskin; Sergey A. Nizkorodov

2008-01-01

290

Producing Persistent, High-Current, High-Duty-Factor H- Beams for Routine 1 MW Operation of SNS  

SciTech Connect

Since 2009, SNS has been producing neutrons with ion beam powers near 1 MW, which requires the extraction of ~50 mA H- ions from the ion source with a ~5% duty factor. The 50 mA are achieved after an initial dose of ~3 mg of Cs and heating the Cs collar to ~170 C. The 50 mA normally persist for the entire 4-week source service cycles. Fundamental processes are reviewed to elucidate the persistence of the SNS H- beams without a steady feed of Cs and why the Cs collar temperature may have to be kept near 170 C.

Stockli, Martin P [ORNL; Han, Baoxi [ORNL; Hardek, Thomas W [ORNL; Kang, Yoon W [ORNL; Murray Jr, S N [ORNL; Pennisi, Terry R [ORNL; Piller, Chip [ORNL; Santana, Manuel [ORNL; Welton, Robert F [ORNL

2012-01-01

291

Process for reproducibly preparing titanium subhydride  

DOEpatents

Titanium subhydride is produced in a reactor by heating a selected amount of finely divided titanium compound at a selected temperature for a selected period of time under dynamic vacuum conditions. Hydrogen is removed substantially uniformly from each powder grain and there is produced a subhydride of substantially uniform titanium-hydrogen composition. Selection of the amount, temperature and time produces a subhydride of selected titanium-hydrogen composition.

Carlson, Richard S. (West Alexandria, OH)

1982-01-01

292

A method of producing high quality oxide and related films on surfaces  

SciTech Connect

Aluminum oxide or aluminum nitride films were deposited on MBE grown GaAs(100) using a novel cryogenic-based reactive thin film deposition technique. The process involves the condensation of molecular oxygen, ammonia or other gases normally used for reactive thin film deposition on the substrate before the metal is deposited. The metal vapor is deposited into this layer and reacts with the molecular solid form the desired compound or a precursor than can be thermally decomposed to generate the desired compound. The films produced by this method are free of impurities and the low temperatures can be used to control the film and interfacial structure. The process can be easily integrated with existing MBE-systems and on going research using the same apparatus suggests than photon or electron irradiation could also be used to promote the reactions needed to give the intended material.

Ruckman, M.W.; Strongin, M. (Brookhaven National Lab., Upton, NY (United States)); Gao, Yongli (Rochester Univ., NY (United States). Dept. of Physics and Astronomy)

1991-01-01

293

A method of producing high quality oxide and related films on surfaces  

SciTech Connect

Aluminum oxide or aluminum nitride films were deposited on MBE grown GaAs(100) using a novel cryogenic-based reactive thin film deposition technique. The process involves the condensation of molecular oxygen, ammonia or other gases normally used for reactive thin film deposition on the substrate before the metal is deposited. The metal vapor is deposited into this layer and reacts with the molecular solid form the desired compound or a precursor than can be thermally decomposed to generate the desired compound. The films produced by this method are free of impurities and the low temperatures can be used to control the film and interfacial structure. The process can be easily integrated with existing MBE-systems and on going research using the same apparatus suggests than photon or electron irradiation could also be used to promote the reactions needed to give the intended material.

Ruckman, M.W.; Strongin, M. [Brookhaven National Lab., Upton, NY (United States); Gao, Yongli [Rochester Univ., NY (United States). Dept. of Physics and Astronomy

1991-12-31

294

Optical pyrometer system for collisionless shock experiments in high-power laser-produced plasmas  

SciTech Connect

A temporally and spatially resolved optical pyrometer system has been fielded on Gekko XII experiments. The system is based on the self-emission measurements with a gated optical imager (GOI) and a streaked optical pyrometer (SOP). Both detectors measure the intensity of the self-emission from laser-produced plasmas at the wavelength of 450 nm with a bandpass filter with a width of {approx}10 nm in FWHM. The measurements were calibrated with different methods, and both results agreed with each other within 30% as previously reported [T. Morita et al., Astrophys. Space Sci. 336, 283 (2011)]. As a tool for measuring the properties of low-density plasmas, the system is applicable for the measurements of the electron temperature and density in collisionless shock experiments [Y. Kuramitsu et al., Phys. Rev. Lett. 106, 175002 (2011)].

Morita, T.; Sakawa, Y.; Kuramitsu, Y.; Sano, T.; Takabe, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Dono, S.; Ide, T.; Tanji, H.; Shiroshita, A. [Graduate School of Engineering, Osaka University, 1-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Shibata, S.; Aoki, H. [Graduate School of Science, Osaka University, 1-1 Machikane-yama, Toyonaka, Osaka 560-0043 (Japan); Waugh, J. N.; Woolsey, N. C. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Gregory, C. D. [LULI, Ecole Polytechnique, CNRS, CEA, UPMC, Route de Saclay, 91128 Palaiseau (France)

2012-10-15

295

Method and apparatus for producing high purity and unagglomerated submicron particles  

US Patent & Trademark Office Database

A method and apparatus for reacting sodium vapor with gaseous chlorides in a flame to produce nanoscale particles of un-oxidized metals, composites and ceramics. The flame is operated under conditions which lead to condensation of a NaCl by-product onto the particles. The condensate encapsulates the particles and aids in controlling desired particle size and preventing undesirable agglomeration among the particles during synthesis. Following synthesis, oxidation of the particles is inhibited by the encapsulation and handling character of the products is greatly enhanced. Electron microscopy has revealed that synthesized products are composed of discrete nanoparticles in a NaCl matrix. The NaCl encapsulate has been effectively removed from the particles by both washing and known sublimation technique at 800.degree. C. under low pressure.

1996-03-12

296

Quantitative measurement of hard x-ray spectra for high intensity laser produced plasma  

SciTech Connect

X-ray line spectra ranging from 17 to 77 keV were quantitatively measured with a Laue spectrometer, composed of a cylindrically curved crystal and a detector. Either a visible CCD detector coupled with a CsI phosphor screen or an imaging plate can be chosen, depending on the signal intensities and exposure times. The absolute sensitivity of the spectrometer system was calibrated using pre-characterized laser-produced x-ray sources and radioisotopes. The integrated reflectivity for the crystal is in good agreement with predictions by an open code for x-ray diffraction. The energy transfer efficiency from incident laser beams to hot electrons, as the energy transfer agency for specific x-ray line emissions, is derived as a consequence of this work.

Zhang, Z.; Nishimura, H.; Namimoto, T.; Fujioka, S.; Arikawa, Y.; Hosoda, H.; Azechi, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Nishikino, M.; Kawachi, T.; Sagisaka, A.; Orimo, S.; Ogura, K.; Pirozhkov, A.; Yogo, A.; Kiriyama, H.; Kondo, K. [Quantum Beam Science Directorate, Kansai Photon Science Institute, JAEA, Kyoto 619-0215 (Japan); Okano, Y. [Laser Research Center for Molecular Science, Institute for Molecular Science, National Institute of Natural Science 38 Nishigo-Naka, Myodaiji, Okazaki 444-8585 (Japan); Ohshima, S. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871 (Japan); Pioneering Research Unit for Next Generation, Kyoto University, Uji 611-0011 (Japan)

2012-05-15

297

High intracolonic acetaldehyde values produced by a bacteriocolonic pathway for ethanol oxidation in piglets.  

PubMed Central

BACKGROUND: Human colonic contents and many colonic microbes produce considerable amounts of acetaldehyde from ethanol in vitro. AIMS: To examine in piglets if acetaldehyde is produced in the colon also in vivo, and if so, what is the fate of intracolonically formed acetaldehyde. ANIMALS: Seventeen native, non-fasted female piglets (20-25 kg) were used. METHODS: Six piglets received either 1.5 g/kg bw or 2.5 g/kg bw of ethanol intravenously. In seven piglets, 0.7 g or 1.75 g of ethanol/kg bw was administered intravenously, followed by a subsequent intragastric ethanol infusion of 1.8 g/kg bw and 4.5 g/kg bw, respectively. The samples of colonic contents for the assessment of ethanol and acetaldehyde concentrations were obtained up to seven hours. In four additional piglets, the intracolonic values of ethanol, acetaldehyde, and acetate were observed for 60 minutes after an intracolonic infusion of acetaldehyde solution. RESULTS: A raised intracolonic, endogenous acetaldehyde concentration (mean (SEM); 36 (9) microM) was found in all piglets before ethanol infusion. After the infusion of ethanol, intracolonic ethanol and acetaldehyde values increased in parallel, reaching the peak values 57 (4) mM of ethanol and 271 (20) microM of acetaldehyde in the group that received the highest dose of ethanol. A positive correlation (r = 0.45; p < 0.001) was found between intracolonic ethanol and acetaldehyde values. Acetaldehyde administered intracolonically was mainly metabolised to acetate but also to ethanol in the colon. CONCLUSIONS: Significant endogenous intracolonic acetaldehyde values can be found in the normal porcine colon. Furthermore, our results suggest the existence of a bacteriocolonic pathway for ethanol oxidation. Increased amounts of acetaldehyde are formed intracolonically from ingested ethanol by this pathway.

Jokelainen, K; Matysiak-Budnik, T; Makisalo, H; Hockerstedt, K; Salaspuro, M

1996-01-01

298

Effects of apple cider vinegars produced with different techniques on blood lipids in high-cholesterol-fed rats.  

PubMed

Red delicious apples were used to produce natural apple cider with and without inclusion of maceration. Traditional surface and industrial submersion methods were then applied to make vinegar from apple ciders. Apple cider vinegar samples produced with inclusion of maceration in the surface method had the highest total phenolic content, chlorogenic acid, ORAC, and TEAC levels. Cholesterol and apple vinegar samples were administered using oral gavage to all groups of rats except the control group. Apple cider vinegars, regardless of the production method, decreased triglyceride and VLDL levels in all groups when compared to animals on high-cholesterol diets without vinegar supplementation. Apple cider vinegars increased total cholesterol and HDL and LDL cholesterol levels and decreased liver function tests when compared to animals on a high-cholesterol diet without vinegar supplementation. A high-cholesterol diet resulted in hepatic steatosis. VSBM and VSB groups significantly decreased steatosis. PMID:21561165

Budak, Nilgun H; Kumbul Doguc, Duygu; Savas, Cagri M; Seydim, Atif C; Kok Tas, Tugba; Ciris, Metin I; Guzel-Seydim, Zeynep B

2011-05-18

299

Cold highly ionized ions: Comparison of energies of recoil ions produced by heavy ions and by synchrotron radiation x rays  

SciTech Connect

The energies of highly excited, high-charge-state recoil ions produced by fast heavy-ion impact on target atoms (''hammer'' method) have been compared with the energies of similar-charge-state recoil ions produced by vacancy cascades subsequent to inner-shell photoabsorption of tuned synchrotron radiation x rays (''scalpel'' method). These comparisons show that the ''hammer'' method leads to recoil ion temperatures typically 4 orders of magnitude lower than those which occur in plasma sources in which ions of similar ionization and excitation states have comparable abundance, while the ''scalpel'' method leads to temperatures up to 6 orders of magnitude lower. Advantages and drawbacks of each method for potential precision spectroscopy of stored or trapped high charge state ions, and for production of extracted beams of low emittance for use in secondary ion-atom collision studies at eV to keV energies are discussed. 20 refs.

Sellin, I.A.; Levin, J.C.; O, C.S.; Cederquist, H.; Elston, S.B.; Short, R.T.; Schmidt-Boecking, H.

1987-01-01

300

High precision Penning trap mass spectrometry of rare isotopes produced by projectile fragmentation  

NASA Astrophysics Data System (ADS)

The Low Energy Beam and Ion Trap (LEBIT) facility combines high precision Penning trap mass spectrometry with fast beam projectile fragmentation and high pressure gas stopping techniques. Advanced ion manipulation, such as high efficiency continuous mass selection in an ion-guide and radio-frequency ion accumulation and bunching, are used to purify, cool, and pulse the beam. Recent mass measurements include ^63-66Fe, ^66As, and ^32Si. The neutron-rich iron isotopes access the N = 40 subshell closure. The new significantly lower mass uncertainty makes ^66As a candidate to test the CVC hypothesis. ^32Si, member of the A = 32, T = 2 quintet, provides the most precise test of the isobaric multiplet mass equation . An overview of the various aspects of ion manipulation and some of the resulting measurements will be presented.

Kwiatkowski, Anna; Bachelet, C.; Barquest, B. R.; Bollen, G.; Campbell, C. M.; Ferrer, R.; Guenaut, C.; Lincoln, D.; Morrissey, D. J.; Pang, G. K.; Prinke, A. M.; Ringle, R.; Savory, J.; Schwarz, S.; Block, M.; Schury, P.; Folden, C. M., III; Melconian, D.; Sjue, S. K. J.

2009-10-01

301

P-Value Precision and Reproducibility  

PubMed Central

Summary P-values are useful statistical measures of evidence against a null hypothesis. In contrast to other statistical estimates, however, their sample-to-sample variability is usually not considered or estimated, and therefore not fully appreciated. Via a systematic study of log-scale p-value standard errors, bootstrap prediction bounds, and reproducibility probabilities for future replicate p-values, we show that p-values exhibit surprisingly large variability in typical data situations. In addition to providing context to discussions about the failure of statistical results to replicate, our findings shed light on the relative value of exact p-values vis-a-vis approximate p-values, and indicate that the use of *, **, and *** to denote levels .05, .01, and .001 of statistical significance in subject-matter journals is about the right level of precision for reporting p-values when judged by widely accepted rules for rounding statistical estimates.

Boos, Dennis D.; Stefanski, Leonard A.

2011-01-01

302

Ablation produced using a toroidal High Intensity Focused Ultrasound device is independent of hepatic perfusion  

Microsoft Academic Search

In the liver, the efficacy of radiofrequency or HIFU ablation is impaired by blood perfusion. This can be overcome by hepatic inflow occlusion using a Pringle manoeuver. Here we report the in vivo evaluation of ablations performed in the liver using a surgical toroidal High Intensity Focused Ultrasound (HIFU) device used during an open procedure with and without hepatic inflow

David Melodelima; William A. N'djin; Julia Favre; Hubert Parmentier; Michel Rivoire; Jean Yves Chapelon

2011-01-01

303

Method of producing highly oxidized superconductors containing barium, copper, and a third metal  

DOEpatents

Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known syntheses in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed.

Morris, Donald E. (Kensington, CA)

1996-01-01

304

Reliable Generation of Stable High Titer Producer Cell Lines for Gene Therapy  

Microsoft Academic Search

Objective: Retroviral vectors represent one of the most robust technologies for in vivo expression of heterologous gene sequences and are still the most commonly used vectors in clinical gene therapy trials. The production of high titer retroviral preparations, however, can be a problematic procedure for certain constructs. Methods: GALV- or RD114-pseudotyped retroviral particles carrying selectable fluorescence markers or drug resistance

Ina Rattmann; Veronika Kleff; Anja Feldmann; Carsten Ludwig; Ursula Regina Sorg; Bertram Opalka; Thomas Moritz; Michael Flasshove

2007-01-01

305

Selenium bioavailability from naturally produced high-selenium peas and oats in selenium-deficient rats  

Technology Transfer Automated Retrieval System (TEKTRAN)

We determined the bioavailability of selenium (Se) from yellow peas and oats harvested from high-Se soil of South Dakota, United States. The Se concentrations of the peas and oats were 13.5 ± 0.2 and 2.5 ± 0.1 mg/kg, respectively. Male weanling Sprague-Dawley rats were depleted of Se by feeding them...

306

Leukocyte interleukins induce cultured endothelial cells to produce a highly organized, glycosaminoglycan-rich pericellular matrix  

Microsoft Academic Search

We report here that interleukins have a dramatic effect on extracellular matrix production by cultured endothelial cells. Human umbilical vein endothelial cells incubated with growth media conditioned by lectin-activated human peripheral blood mononuclear leukocytes undergo marked changes in cell shape and elaborate a highly organized extracel- lular material that is not detectable in untreated cultures. This material has the following

R. Montesano; A. MOSSAZ; J.-E. RYSER; L. ORCI; P. VASSALLI

1984-01-01

307

Highly protective E2–CSFV vaccine candidate produced in the mammary gland of adenoviral transduced goats  

Microsoft Academic Search

Classical swine fever virus is the etiological agent of the most economically important highly contagious disease of swine worldwide. E2 is the major envelope glycoprotein present as a homodimer on the outer surface of the virus and represents an important target for the induction of neutralizing immune response against the viral infection. The E2 extracellular domain was expressed in the

Jorge R. Toledo; Oliberto Sánchez; Raquel Montesino; Omar Farnos; Maria P. Rodríguez; Pastor Alfonso; Nayrobis Oramas; Elsa Rodríguez; Elaine Santana; Ernesto Vega; Llilianne Ganges; Maria T. Frias; José Cremata; Maritza Barrera

2008-01-01

308

(Search for strange quark matter and antimatter produced in high energy heavy ion collisions)  

SciTech Connect

This document describes the development and progress of our group's research program in high energy heavy ion physics. We are a subset of the Yale experimental high energy physics effort (YAUG group) who became interested in the physics of high energy heavy ions in 1988. Our interest began with the possibility of performing significant searches for strange quark matter. As we learned more about the subject and as we gained experimental experience through our participation in AGS experiment 814, our interests have broadened. Our program has focused on the study of new particles, including (but not exclusively) strange quark matter, and the high sensitivity measurement of other composite nuclear systems such as antinuclei and various light nuclei. The importance of measurements of the known, but rare, nuclear systems lies in the study of production mechanisms. A good understanding of the physics and phenomenology of rare composite particle production in essential for the interpretation of limits to strange quark matter searches. We believe that such studies will also be useful in probing the mechanisms involved in the collision process itself. We have been involved in the running and data analysis for AGS E814. We have also worked on the R D for AGS E864, which is an approved experiment designed to reach sensitivities where there will be a good chance of discovering strangelets or of setting significant limits on the parameters of strange quark matter.

Not Available

1992-01-01

309

High magnetic susceptibility produced in high-velocity frictional tests on core samples from the Chelungpu fault in Taiwan  

NASA Astrophysics Data System (ADS)

We carried out high-velocity frictional tests on crushed fault gouge from core samples from Hole B of the Taiwan Chelungpu-fault Drilling Project to investigate the cause of high magnetic susceptibilities in the fault core. Black ultracataclasite resembling that observed in Hole B formed during the experiments, even under low axial stress of 0.5 to 1.5 MPa. The bulk magnetic susceptibility of the tested samples was proportional to the frictional work applied and increased as slip increased. Thermomagnetic analysis of the samples before frictional testing revealed that magnetization increased at temperatures above 400 °C, probably because of thermal decomposition of paramagnetic minerals. Both the thermally and mechanically induced formation of ferrimagnetic minerals by high-velocity friction might have caused a magnetic susceptibility anomaly. Our experimental results support the assumption that heat generation of short duration, even if it is below the melting point, can increase magnetic susceptibility.

Tanikawa, Wataru; Mishima, Toshiaki; Hirono, Tetsuro; Lin, Weiren; Shimamoto, Toshihiko; Soh, Wonn; Song, Sheng-Rong

2007-08-01

310

Every good virtue you ever wanted in a Q-switched solid-state laser and more: Monolithic, diode-pumped, self-Q-switched, highly reproducible, diffraction-limited Nd:YAG laser  

Microsoft Academic Search

The applications of Q-switched lasers are well known, for example, laser radar, laser remote sensing, satellite orbit determination, Moon orbit and 'moon quake' determination, satellite laser communication, and many nonlinear optics applications. Most of the applications require additional properties of the Q-switched lasers, such as single-axial and\\/or single-transverse mode, high repetition rate, stable pulse shape and pulse width, or ultra

Y. C. Chen; K. K. Lee

1993-01-01

311

Beta-Lactamases Produced by a Pseudomonas aeruginosa Strain Highly Resistant to Carbenicillin  

PubMed Central

A Pseudomonas aeruginosa strain isolated at Besançon Hospital, France, proved to be highly resistant to carbenicillin and showed a high hydrolytic activity toward this antibiotic. We clearly demonstrated that two ?-lactamases were synthetized: one of them, constitutive, has its enzymatic activity directed mainly toward penicillins, and carbenicillin appears to be its best substrate (higher Vmax); thus, this ?-lactamase is a “carbenicillinase” that differs from the well-known “TEM-like” enzymes. The isoelectric point of this carbenicillinase is 5.30 ± 0.03. The other one is an inducible cephalosporinase, very similar to the cephalosporinases usually found in these organisms. Its isoelectric point is 8.66 ± 0.04. These two enzymes have been separated by affinity chromatography and isoelectric focusing. The kinetic constants were measured by computerized microacidimetry. Images

Labia, Roger; Guionie, Marlene; Masson, Jean-Michel; Philippon, Alain; Barthelemy, Michel

1977-01-01

312

A high-sugar diet produces obesity and insulin resistance in wild-type Drosophila  

PubMed Central

SUMMARY Insulin-resistant, ‘type 2’ diabetes (T2D) results from a complex interplay between genes and environment. In particular, both caloric excess and obesity are strongly associated with T2D across many genetic backgrounds. To gain insights into how dietary excess affects insulin resistance, we studied the simple model organism Drosophila melanogaster. Larvae reared on a high-sugar diet were hyperglycemic, insulin resistant and accumulated fat – hallmarks of T2D – compared with those reared on control diets. Excess dietary sugars, but not fats or proteins, elicited insulin-resistant phenotypes. Expression of genes involved in lipogenesis, gluconeogenesis and ?-oxidation was upregulated in high-sugar-fed larvae, as were FOXO targets, consistent with known mechanisms of insulin resistance in humans. These data establish a novel Drosophila model of diet-induced insulin resistance that bears strong similarity to the pathophysiology of T2D in humans.

Musselman, Laura Palanker; Fink, Jill L.; Narzinski, Kirk; Ramachandran, Prasanna Venkatesh; Hathiramani, Sumitha Sukumar; Cagan, Ross L.; Baranski, Thomas J.

2011-01-01

313

Nano-silicon carbide reinforced aluminium produced by high-energy milling and hot consolidation  

Microsoft Academic Search

High-energy milling was studied for the ex situ strengthening of aluminium with silicon carbide (SiC) nanopowders. Heptane was used as a milling agent for both planetary- and attritor ball milling. Considering the different milling techniques and the differences in the resulting powders, effective dispersion of the nano SiC was achieved. Composite samples compacted by hot pressing showed an increase in

L. Kollo; C. R. Bradbury; R. Veinthal; C. Jäggi; M. Leparoux

2011-01-01

314

Galactic anisotropy of UltraHigh Energy Cosmic Rays produced by CDM-related mechanisms  

Microsoft Academic Search

We briefly review current theoretical and experimental status of Ultra-High\\u000aEnergy Cosmic Rays. We show that ``top-down'' mechanisms of UHE CR which\\u000ainvolve heavy relic particle-like objects predict Galactic anisotropy of\\u000ahighest energy cosmic rays at the level of minimum $\\\\sim 20%$. This anisotropy\\u000ais large enough to be either observed or ruled out in the next generation of\\u000aexperiments.

S. L. Dubovsky; P. G. Tinyakov

1998-01-01

315

Generation of high-order harmonics using laser-produced rare-gas-like ions  

Microsoft Academic Search

We report the first observation of high-order harmonic waves from rare-gas-like ions excited by a subpicosecond KrF excimer laser. At an intensity of 1015 W\\/cm2, the highest orders of observed harmonics are the ninth (27.6 nm) in Li+, the eleventh (22.6 nm) in Na+, and the thirteenth (19.1 nm) in K+. The advantage of such ions as nonlinear media for

Yasuhiro Akiyama; Katsumi Midorikawa; Yuuki Matsunawa; Yutaka Nagata; Minoru Obara; Hideo Tashiro; Koichi Toyoda

1992-01-01

316

High gravity fermentation of sugarcane molasses to produce ethanol: Effect of nutrients  

Microsoft Academic Search

Fermentation efficiency of more than 85% was obtained by high gravity fermentation of 33–34°Bx (spec. gravity ?1.134) molasses\\u000a medium with certain nutrients, instead of generally employed medium containing ?16% (w\\/v) total sugar (spec. gravity ?1.090)\\u000a for ethanol fermentation in distilleries to get maximum 80–85% conversion. The fermenting yeast, Saccharomyces, has varied capabilities, depending on the species and nutrition for fermenting

P. Pradeep; O. V. S. Reddy

2010-01-01

317

NREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar Cells (Fact Sheet)  

SciTech Connect

Researchers at the National Renewable Energy Laboratory (NREL) are finding new ways to manufacture thin-film solar cells made from copper, indium, gallium, and selenium - called CIGS cells - that are different than conventional CIGS solar cells. Their use of high-temperature glass, designed by SCHOTT AG, allows higher fabrication temperatures, opening the door to new CIGS solar cells employing light-absorbing materials with wide 'bandgaps.'

Not Available

2012-09-01

318

Viral infection switches non-plasmacytoid dendritic cells into high interferon producers  

Microsoft Academic Search

Type I interferons (IFN-I) are important cytokines linking innate and adaptive immunity. Plasmacytoid dendritic cells make high levels of IFN-I in response to viral infection and are thought to be the major source of the cytokines in vivo. Here, we show that conventional non-plasmacytoid dendritic cells taken from mice infected with a dendritic-cell-tropic strain of lymphocytic choriomeningitis virus make similarly

Sandra S. Diebold; Maria Montoya; Hermann Unger; Lena Alexopoulou; Polly Roy; Linsey E. Haswell; Aymen Al-Shamkhani; Richard Flavell; Persephone Borrow; Caetano Reis e. Sousa

2003-01-01

319

Furan compounds produced by heating of fermented high-sacchariferous media  

Microsoft Academic Search

5-Methylfurfural diethyl acetal, 5-methylfuran acid ester, and 4-hydroxypentanoic acid ethyl ester were first identified in\\u000a high-sacchariferous corn media subjected to alcoholic fermentation byMucor X-I culture and in aged sweet wines by means of GLC., GLC-MS, and TLC., as well as by UV and IR spectroscopic examinations.\\u000a These substances are products of enzymatic esterification of sugars followed by their dehydration by

A. F. Pisarnitskii; I. V. Ulezlo

2000-01-01

320

Quantitative determination of gibberellins by high performance liquid chromatography from various gibberellins producing Fusarium strains  

Microsoft Academic Search

High performance liquid chromatographic (HPLC) method was developed for analysis of seven gibberellins, i.e., GA3, GA4, GA7, GA3 methyl ester, GA7 methyl ester 3,13 diacetate, GA7 methyl ester, and fusaric acid, using an isocratic system. Method was used for estimation of gibberellins from different\\u000a Fusarium strains. Gibberellins were extracted from 28 strains of Fusarium, out of which six strains of

Kirti Bhalla; Shashi Bala Singh; Rashmi Agarwal

2010-01-01

321

Nanometer-size surface features produced by single, low energy, highly charged ions  

Microsoft Academic Search

We have studied the interaction of ions with solid surfaces in the limit of slow, highly charged ions (Xe{sup 44+} 0.1--20 keV\\/{ital q}). Using atomic force microscopy we are able to see individual ion impact sites on mica, approximately one site per incident ion. Such features are typically circular with â¼20 nm diameter. This damage may be caused by local

D. C. Parks; R. Bastasz; R. W. Schmieder; M. Stoeckli

1995-01-01

322

Selection and optimization of a high-producing tissue culture of Panax ginseng C. A. Meyer  

Microsoft Academic Search

Biomass growth, ginsenoside and polysaccharide production in different ginseng tissue cultures, including callus culture,\\u000a adventitious root culture and hairy root culture, were studied, and the active component contents were compared with that\\u000a of native ginseng roots. The adventitious root culture was confirmed to be a very nice system, which grew fast and contained\\u000a a rather high content of ginsenosides. Then,

T. Huang; Wen Yuan Gao; J. Wang; Y. Cao; Y. X. Zhao; L. Q. Huang; C. X. Liu

2010-01-01

323

Development of Compton radiography using high-Z backlighters produced by ultra-intense lasers  

SciTech Connect

High-energy x-ray backlighters will be valuable for radiography experiments at the National Ignition Facility (NIF), and for radiography of imploded inertial confinement fusion cores using Compton scattering to observe cold, dense plasma. Key considerations are the available backlight brightness, and the backlight size. To quantify these parameters we have characterized the emission from low- and high-Z planar foils irradiated by intense picosecond and femtosecond laser pulses from the TITAN laser facility at Lawrence Livermore National Laboratory. Spectra generated by a sequence of elements from Mo to Pb, spanning the x-ray energy range from 17 keV to 75 keV, have been recorded using a Charged Coupled Device (CCD) in single hit regime and a Dual Crystal Spectrometer (DCS). High-resolution point-projection 2D radiographs have also been recorded on Fuji BaFBr:Eu2 image plates using calibrated resolution grids. We discuss the results in light of the requirements for applications at NIF.

Tommasini, Riccardo; Park, Hye-Sook; Patel, Prav; Maddox, Brian; Le Pape, Sebastien; Hatchett, Stephen P.; Remington, Bruce A.; Key, Michael H.; Izumi, Nobuhiko; Tabak, Max; Koch, Jeffrey A.; Landen, Otto L.; Hey, Dan; MacKinnon, Andy; Seely, John; Holland, Glenn; Hudson, Larry; Szabo, Csilla [Lawrence Livermore National Laboratory, Livermore CA (United States); Naval Research Laboratory, Washington DC (United States); National Institute of Standards and Technology, Gaithersburg, MD (United States)

2007-08-02

324

Streptomyces sp. JS520 produces exceptionally high quantities of undecylprodigiosin with antibacterial, antioxidative, and UV-protective properties.  

PubMed

A Gram-positive, red-pigment-producing bacterial strain, designated JS520 was isolated from the pristine sediment from the cave on mountain Miroc in Serbia. Strain was confirmed to belong to Streptomyces genus based on phenotypic and genetic analysis. Streptomyces sp. JS520 has the ability to produce exceptionally high amounts of deep red pigment into both solid and liquid media. Liquid chromatography and mass spectroscopy of the purified pigments revealed the major component to be undecylprodigiosin (93 %) with minor component being oxidatively cyclized derivative. The pigment production was affected by medium composition, temperature, pH, and the aeration rate. By medium optimization, yields of undecylprodigiosin of 138 mg l(-1) were achieved, what is the highest level of undecylprodigiosin production reported for the members of Gram-positive Streptomyces genus. Purified pigment had antimicrobial properties against bacterial Bacillus and Micrococcus species (50 ?g ml(-1)) and against Candida albicans species (100-200 ?g ml(-1) range). The ability to affect auto-oxidation of the linoleic acid was demonstrated for the purified undecylprodigiosin, suggesting antioxidative properties of this pigment. Multiple ecophysiological roles of the pigment were revealed by comparing cultures grown under pigment-producing and pigment-nonproducing conditions. Cells grown under undecylprodigiosin-producing conditions could tolerate presence of hydrogen peroxide exhibiting three times smaller zones of inhibition at 100 mM H(2)O(2). Undecylprodigiosin-producing cells were also less susceptible to tetracycline, kanamycin, chloramphenicol, and 8-hydroxyquinoline. While the growth of the cells not producing pigment was completely inhibited by 15 min of exposure to ultraviolet light (254 nm), cells producing undecylprodigiosin and cells supplied with purified pigment in vitro showed survival rates at 22 and 8 %, respectively. PMID:22767180

Stankovic, Nada; Radulovic, Vanja; Petkovic, Milos; Vuckovic, Ivan; Jadranin, Milka; Vasiljevic, Branka; Nikodinovic-Runic, Jasmina

2012-07-06

325

Research on producing high quality diffractive optical elements in volume at a low cost  

NASA Astrophysics Data System (ADS)

Diffractive Optical Elements (DOEs) can be utilized in a variety of possible applications in modern optical, as well as optoelectronic systems. The current roadblock for application of DOEs in consumer products is not the feasibility of the approach, as numerous applications have been successfully demonstrated. In order for the breakthrough to occur in industry, it is important to determine a convenient and cost-effective method for manufacturing DOEs. The industry will improve the design of their legacy systems and start including DOEs only when the performance improvement (which the utilization of DOEs achieves), can be purchased with a minimal amount of additional capital investment and cost-per-part. Therefore, the focus of this dissertation was to find a cost-effective method of fabricating large quantities of DOEs with currently available fabrication tools. Direct-write approaches were investigated to fabricate high-quality masters for a subsequent replication procedure based upon molding or casting. Electron-Beam Direct-Write was carried-out in a positive Novolac-based photo-resist which provides dry etch resistivity. Another focus of this development was to find a way to minimize Electron-Beam writing time for a given element. Proximity effect characterization and compensation has been carried-out in order to increase the fidelity of the pattern reproduction. A dry-etching procedure has been developed in order to transfer resist profiles into the substrate material. During this transfer step, the etch rates of resist and substrate material can be controlled; this in turn allows a choice of final feature depth in the substrate material (depending on refractive index and wavelength in use). Two Gray-Scale masking approaches were developed to allow the cost-effective mass fabrication of DOEs in a single optical exposure step. Thin film evaporation of Inconel achieves high-quality masks at a high price. High Energy Beam Sensitive Glass, the second mask material investigated, allows a much simplified and therefore cost-effective mask fabrication. The fabrication procedure for these masks is identical to Direct-write procedures allowing the application of the research generated for this scheme to the Gray-Scale mask fabrication. Using these types of masks in reduction stepper systems will allow a high-quality mass fabrication of DOEs at a low cost.

Daschner, Walter

1997-11-01

326

Reproducible switching effect in thin oxide films for memory applications  

NASA Astrophysics Data System (ADS)

Thin oxide films with perovskite or related structures and with transition metal doping show a reproducible switching in the leakage current with a memory effect. Positive or negative voltage pulses can switch the resistance of the oxide films between a low- and a high-impedance state in times shorter than 100 ns. The ratio between these two states is typically about 20 but can exceed six orders of magnitude. Once a low-impedance state has been achieved it persists without a power connection for months, demonstrating the feasibility of nonvolatile memory elements. Even multiple levels can be addressed to store two bits in such a simple capacitor-like structure.

Beck, A.; Bednorz, J. G.; Gerber, Ch.; Rossel, C.; Widmer, D.

2000-07-01

327

The magnitude of variability produced by methods used to estimate annual stormwater contaminant loads for highly urbanised catchments.  

PubMed

Stormwater contaminant loading estimates using event mean concentration (EMC), rainfall/runoff relationship calculations and computer modelling (Model of Urban Stormwater Infrastructure Conceptualisation--MUSIC) demonstrated high variability in common methods of water quality assessment. Predictions of metal, nutrient and total suspended solid loadings for three highly urbanised catchments in Sydney estuary, Australia, varied greatly within and amongst methods tested. EMC and rainfall/runoff relationship calculations produced similar estimates (within 1 SD) in a statistically significant number of trials; however, considerable variability within estimates (?50 and ?25 % relative standard deviation, respectively) questions the reliability of these methods. Likewise, upper and lower default inputs in a commonly used loading model (MUSIC) produced an extensive range of loading estimates (3.8-8.3 times above and 2.6-4.1 times below typical default inputs, respectively). Default and calibrated MUSIC simulations produced loading estimates that agreed with EMC and rainfall/runoff calculations in some trials (4-10 from 18); however, they were not frequent enough to statistically infer that these methods produced the same results. Great variance within and amongst mean annual loads estimated by common methods of water quality assessment has important ramifications for water quality managers requiring accurate estimates of the quantities and nature of contaminants requiring treatment. PMID:23064853

Beck, H J; Birch, G F

2012-10-13

328

Process for producing high purity silicon nitride by the direct reaction between elemental silicon and nitrogen-hydrogen liquid reactants  

SciTech Connect

A process is disclosed for producing, at a low temperature, a high purity reaction product consisting essentially of silicon, nitrogen, and hydrogen which can then be heated to produce a high purity alpha silicon nitride. The process comprises: reacting together a particulate elemental high purity silicon with a high purity nitrogen-hydrogen reactant in its liquid state (such as ammonia or hydrazine) having the formula: N[sub n]H[sub (n+m)] wherein: n=1--4 and m=2 when the nitrogen-hydrogen reactant is straight chain, and m=0 when the nitrogen-hydrogen reactant is cyclic. High purity silicon nitride can be formed from this intermediate product by heating the intermediate product at a temperature of from about 1200--1700 C for a period from about 15 minutes up to about 2 hours to form a high purity alpha silicon nitride product. The discovery of the existence of a soluble Si-N-H intermediate enables chemical pathways to be explored previously unavailable in conventional solid state approaches to silicon-nitrogen ceramics. 1 figure.

Pugar, E.A.; Morgan, P.E.D.

1990-06-19

329

Observations of the filamentation of high-intensity laser-produced electron beams  

NASA Astrophysics Data System (ADS)

Filamented electron beams have been observed to be emitted from the rear of thin solid targets irradiated by a high-intensity short-pulse laser when there is low-density plasma present at the back of the target. These observations are consistent with a laser-generated beam of relativistic electrons propagating through the target, which is subsequently fragmented by a Weibel-like instability in the low-density plasma at the rear. These measurements are in agreement with particle-in-cell simulations and theory, since the filamentation instability is predicted to be dramatically enhanced when the electron beam density approaches that of the background plasma.

Wei, M. S.; Beg, F. N.; Clark, E. L.; Dangor, A. E.; Evans, R. G.; Gopal, A.; Ledingham, K. W. D.; McKenna, P.; Norreys, P. A.; Tatarakis, M.; Zepf, M.; Krushelnick, K.

2004-11-01

330

Strength and high fatigue properties of ultrafine-grained titanium rods produced by severe plastic deformation  

NASA Astrophysics Data System (ADS)

The formation of an ultrafine-grained structure (UFGS) in titanium by severe plastic deformation significantly increases its mechanical properties, among them fatigue strength. In this work, high mechanical properties of titanium long rods are achieved using a combination of equal-channel angular pressing and subsequent thermal and thermomechanical treatment. The formation of a homogeneous UFGS in a rod of commercial titanium is found to increase the fatigue limit by a factor of about 1.5. Moreover, the fatigue strength of UFGS titanium estimated on notched specimens is higher than that of coarse-grained titanium, which is important for its structural application in medicine.

Semenova, I. P.

2010-09-01

331

Enhanced isochoric heating from fast electrons produced by high-contrast, relativistic-intensity laser pulses.  

PubMed

Thin, mass-limited targets composed of V/Cu/Al layers with diameters ranging from 50 to 300 microm have been isochorically heated by a 300 fs laser pulse delivering up to 10 J at 2x10{19} W/cm{2} irradiance. Detailed spectral analysis of the Cu x-ray emission indicates that the highest temperatures, of the order of 100 eV, have been reached when irradiating the smallest targets with a high-contrast, frequency-doubled pulse despite a reduced laser energy. Collisional particle-in-cell simulations confirm the detrimental influence of the preformed plasma on the bulk target heating. PMID:20366940

Perez, F; Gremillet, L; Koenig, M; Baton, S D; Audebert, P; Chahid, M; Rousseaux, C; Drouin, M; Lefebvre, E; Vinci, T; Rassuchine, J; Cowan, T; Gaillard, S A; Flippo, K A; Shepherd, R

2010-02-25

332

Enhanced Isochoric Heating from Fast Electrons Produced by High-Contrast, Relativistic-Intensity Laser Pulses  

SciTech Connect

Thin, mass-limited targets composed of V/Cu/Al layers with diameters ranging from 50 to 300 {mu}m have been isochorically heated by a 300 fs laser pulse delivering up to 10 J at 2x10{sup 19} W/cm{sup 2} irradiance. Detailed spectral analysis of the Cu x-ray emission indicates that the highest temperatures, of the order of 100 eV, have been reached when irradiating the smallest targets with a high-contrast, frequency-doubled pulse despite a reduced laser energy. Collisional particle-in-cell simulations confirm the detrimental influence of the preformed plasma on the bulk target heating.

Perez, F.; Koenig, M.; Baton, S. D.; Audebert, P.; Chahid, M. [Laboratoire pour l'Utilisation des Lasers Intenses, UMR 7605 CNRS-CEA-X-Paris VI, Ecole Polytechnique, Palaiseau (France); Gremillet, L.; Rousseaux, C.; Drouin, M.; Lefebvre, E.; Vinci, T. [CEA, DAM, DIF, F-91297 Arpajon Cedex (France); Rassuchine, J.; Cowan, T. [Forschungszentrum Dresden-Rossendorf, POB 510119, 01314 Dresden (Germany); Gaillard, S. A. [Forschungszentrum Dresden-Rossendorf, POB 510119, 01314 Dresden (Germany); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); Flippo, K. A. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Shepherd, R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2010-02-26

333

Economical Route to Produce High Seebeck Coefficient Calcium Cobaltate for Bulk Thermoelectric Applications  

SciTech Connect

Phase pure calcium cobaltate (Ca1.24Co1.62O3.86) was prepared by Self-propagating High-temperature Synthesis (SHS) followed by a short post heat treatment. Prepared powders were characterized by XRD for phase purity, and SEM for particle size and distribution. Temperature histories at the center and on the surface of reaction pellet during the SHS process were monitored and recorded. Particles size of synthesized powders was reduced using a planetary mill to increase its specific surface area. Electrical conductivity, thermal conductivity and Seebeck coefficient of the prepared power were measured and figure of merit was reported.

Selig, Jiri [Lamar University; Lin, Sidney [Lamar University; Lin, Hua-Tay [ORNL; Johnson, D Ray [ORNL; Wang, Hsin [ORNL

2011-01-01

334

Laser focus accelerator by relativistic self-focusing and high electric fields in double layers of nonlinear force produced cavitons  

SciTech Connect

The laser focus accelerator with relativistic self-focusing for achieving Z-separated heavy ions of energies beyond 10 GeV was studied experimentally, in detailed numerical work and estimations on intense muon sources, heavy nuclear collisions and generation of new isotopes are on the way. The recently detected inverted double layers in the nonlinear (ponderomotive) force produced cavitons with 10/sup 9/ V/cm nearly static field can be used for electron acceleration. An upgraded present days Antares system with 20 phase-optimized steps should arrive at TeV electrons. The spontaneous high magnetic fields should produce highly directed non-Z-separated ion bunches where the E x B mechanism of Forslund and Brackbill with thermally created electric fields can be improved drastically by nonlinear force generated fields. Further studies were on acceleration by relativistic Doppler shift and by the transverse free electron laser.

Clark, P.J.; Eliezer, S.; Farley, F.J.M.; Goldsworthy, M.P.; Green, F.; Hora, H.; Kelly, J.C.; Lalousis, P.; Luther-Davies, B.; Stening, R.J.

1985-07-15

335

Laser focus accelerator by relativistic self-focusing and high electric fields in double layers of nonlinear force produced cavitons  

NASA Astrophysics Data System (ADS)

The laser focus accelerator with relativistic self-focusing for achieving Z-separated heavy ions of energies beyond 10 GeV was studied experimentally, in detailed numerical work and estimations on intense muon sources, heavy nuclear collisions and generation of new isotopes are on the way. The recently detected inverted double layers in the nonlinear (ponderomotive) force produced cavitons with 109 V/cm nearly static field can be used for electron acceleration. An upgraded present days Antares system with 20 phase-optimized steps should arrive at TeV electrons. The spontaneous high magnetic fields should produce highly directed non-Z-separated ion bunches where the E×B mechanism of Forslund and Brackbill with thermally created electric fields can be improved drastically by nonlinear force generated fields. Further studies were on acceleration by relativistic Doppler shift and by the transverse free electron laser.

Clark, P. J.; Eliezer, S.; Farley, F. J. M.; Goldsworthy, M. P.; Green, F.; Hora, H.; Kelly, J. C.; Lalousis, P.; Luther-Davies, B.; Stening, R. J.; Jin-Cheng, Wang

1985-07-01

336

Apparatus and method for enhanced chemical processing in high pressure and atmospheric plasmas produced by high frequency electromagnetic waves  

DOEpatents

An apparatus and method for creating high temperature plasmas for enhanced chemical processing of gaseous fluids, toxic chemicals, and the like, at a wide range of pressures, especially at atmospheric and high pressures includes an electro-magnetic resonator cavity, preferably a reentrant cavity, and a wave guiding structure which connects an electro-magnetic source to the cavity. The cavity includes an intake port and an exhaust port, each having apertures in the conductive walls of the cavity sufficient for the intake of the gaseous fluids and for the discharge of the processed gaseous fluids. The apertures are sufficiently small to prevent the leakage of the electro-magnetic radiation from the cavity. Gaseous fluid flowing from the direction of the electro-magnetic source through the guiding wave structure and into the cavity acts on the plasma to push it away from the guiding wave structure and the electro-magnetic source. The gaseous fluid flow confines the high temperature plasma inside the cavity and allows complete chemical processing of the gaseous fluids at a wide range of pressures.

Efthimion, Philip C. (Bedminister, NJ); Helfritch, Dennis J. (Flemington, NJ)

1989-11-28

337

Tapping-mode atomic force microscopy produces faithful high-resolution images of protein surfaces.  

PubMed Central

Compared to contact-mode atomic force microscopy (CMAFM), tapping-mode atomic force microscopy (TMAFM) has the advantage of allowing imaging surfaces of macromolecules, even when they are only weakly attached to the support. In this study, TMAFM is applied to two different regular protein layers whose structures are known to great detail, the purple membrane from Halobacterium salinarum and the hexagonally packed intermediate (HPI) layer from Deinococcus radiodurans, to assess the faithfulness of high-resolution TMAFM images. Topographs exhibited a lateral resolution between 1.1 and 1. 5 nm and a vertical resolution of approximately 0.1 nm. For all protein surfaces, TMAFM and CMAFM topographs were in excellent agreement. TMAFM was capable of imaging the fragile polypeptide loop connecting the transmembrane alpha-helices E and F of bacteriorhodopsin in its native extended conformation. The standard deviation (SD) of averages calculated from TMAFM topographs exhibited an enhanced minimum (between 0.1 and 0.9 nm) that can be assigned to the higher noise of the raw data. However, the SD difference, indicating the flexibility of protein subunits, exhibited an excellent agreement between the two imaging modes. This demonstrates that the recently invented imaging-mode TMAFM has the ability to faithfully record high-resolution images and has sufficient sensitivity to contour individual peptide loops without detectable deformations.

Moller, C; Allen, M; Elings, V; Engel, A; Muller, D J

1999-01-01

338

Microstructural Changes Produced by Fatigue in High-Purity Copper Severely Deformed by Cryogenic Rolling  

NASA Astrophysics Data System (ADS)

High-purity Cu (99.995 pct pure) rods were cryogenically rolled through a 90 pct reduction in area and given a very brief low-temperature anneal. The resultant material was highly textured, had very low internal strains, and had a broad distribution of grain sizes with an average grain size of 150 to 300 nm. Samples were tested in stress-control tension-tension fatigue. Fatigue life was strongly improved over that of coarse-grain (CG) copper. The cycling caused significant softening and grain growth, especially at the lower stress amplitudes. Plastic strain was small but creep was evident. Clusters of long parallel protrusions that were quite uniformly spaced about 100 nm apart formed on the sample surfaces during fatiguing. Among the various microstructures seen in the fatigued specimens, transmission electron microscopy (TEM) pictures taken just inside the surface showed parallel dislocation lines many micrometers in length spaced about 100 nm from one another. It is possible that these dislocations are involved in the formation of the protrusions.

Zhang, Kai; Weertman, J. R.

2009-10-01

339

High-Resolution Mass Spectrometric Analysis of Secondary Organic Aerosol Produced by Ozonation of Limonene  

SciTech Connect

Secondary organic aerosol (SOA) particles formed from the ozone-initiated oxidation of limonene are characterized by high-resolution electrospray ionization mass spectrometry in both the positive and negative ion modes. The mass spectra reveal a large number of both monomeric (m/z < 300) and oligomeric (m/z > 300) products of oxidation. A combination of high resolving power (m/?m ~60,000) and Kendrick mass defect analysis makes it possible to unambiguously determine the composition for hundreds of individual compounds in SOA samples. Van Krevelen analysis shows that the SOA compounds are heavily oxidized, with average O:C ratios of 0.43 and 0.50 determined from the positive and negative ion mode spectra, respectively. An extended reaction mechanism for the formation of the first generation SOA molecular components is proposed. The mechanism includes known isomerization and addition reactions of the carbonyl oxide intermediates generated during the ozonation of limonene, and numerous isomerization pathways for alkoxy radicals resulting from the decomposition of unstable carbonyl oxides. The isomerization reactions yield numerous products with a progressively increasing number of alcohol and carbonyl groups, whereas C-C bond scission reactions in alkoxy radicals shorten the carbon chain. Together these reactions yield a large number of isomeric products with broadly distributed masses. A qualitative agreement is found between the number and degree of oxidation of the predicted and measured reaction products in the monomer range.

Walser, Maggie L.; Dessiaterik, Yury; Laskin, Julia; Laskin, Alexander; Nizkorodov, Serguei

2008-02-08

340

Highly protective E2-CSFV vaccine candidate produced in the mammary gland of adenoviral transduced goats.  

PubMed

Classical swine fever virus is the etiological agent of the most economically important highly contagious disease of swine worldwide. E2 is the major envelope glycoprotein present as a homodimer on the outer surface of the virus and represents an important target for the induction of neutralizing immune response against the viral infection. The E2 extracellular domain was expressed in the milk of adenoviral transduced goats at the highest level about 1.2g/L. The recombinant glycoprotein was purified from clarified serum milk by a single metal chelate affinity chromatography step, as a homodimer of approximately 100kDa and purity over 98%. Glycosylation analysis showed the presence of oligomannoside, hybrid and complex type N-glycans, attached to the recombinant E2. The capacity of goat milk-derived E2 antigen to protect pigs from both classical swine fever clinical signs and viral infection was assessed in a vaccination and challenge trial. The immunized pigs became protected after challenge with 10(5) LD(50) of a highly pathogenic CSFV strain. In the context of veterinary vaccines, this expression system has the advantages that the recombinant antigen could be harvested in about 48h after adenoviral transduction with expression levels in the range of g/L. This approach may turn into a scalable expression system for the assessment and production of veterinary vaccines. PMID:18045719

Toledo, Jorge R; Sánchez, Oliberto; Montesino, Raquel; Farnos, Omar; Rodríguez, Maria P; Alfonso, Pastor; Oramas, Nayrobis; Rodríguez, Elsa; Santana, Elaine; Vega, Ernesto; Ganges, Llilianne; Frias, Maria T; Cremata, José; Barrera, Maritza

2007-10-05

341

Effect of Crude Protein on Reproductive Efficiency, Serum Total Protein, and Albumin in the High-Producing Dairy Cow1  

Microsoft Academic Search

Forty-five high-producing dairy cows were assigned randomly in equal numbers and fed one of three isocaloric rations of 12.7, 16.3, or 19.3% crude protein starting at 4 days postpartum and con- tinuing for 91 days. The 19.3% group had fewer days to first observed estrus (27 days) than the 16.3 and 12.7% groups (41 days). The 12.7 and 16.3% groups

E. R. Jordan; L. V. Swanson

1979-01-01

342

Utilization of high lysine-producing strains of Lactobacillus plantarum as starter culture for nutritional improvement of ogi  

Microsoft Academic Search

A high lysine-producing mutant of Lactobacillus plantarum (OG 261-5) derived from a wild type strain (OG 261) previously isolated from fermenting ogi was evaluated for nutritional improvement of ogi in a modified fermentation process. Results indicate that ogi obtained by fermentation with the pure culture of the mutant compared to traditional ogi increased in concentration of available lysine from 228.5

O. O. Adebawo; J. O. Akingbala; J. L. Ruiz-Barba; O. Osilesi

2000-01-01

343

Microbial community structure analysis of produced water from a high-temperature North Sea oil-field  

Microsoft Academic Search

Molecular and culture-based methods were used to investigate the microbial diversity in produced water obtained from the high-temperature\\u000a Troll oil formation in the North Sea. 16S rRNA gene libraries were generated from total community DNA, using universal archaeal\\u000a or bacterial oligonucleotide primer sets. Sequence analysis of 88 clones in the bacterial library indicated that they originated\\u000a from members of Firmicutes

Håkon Dahle; Frøydis Garshol; Marit Madsen; Nils-Kåre Birkeland

2008-01-01

344

Welded Penstock, Produced of High-Strength Steel and Application of Fracture Mechanics Parameters to Structural Integrity Assessment  

Microsoft Academic Search

Application of high-strength steel for welded penstock increased the probability of crack-like defects and in welded joint.\\u000a Structural integrity assessment procedure is presented and applied to welded penstock produced of highstrength steel, comparing\\u000a crack driving force and material crack resistance in terms of J-integral as fracture mechanics parameter. The safety and structural integrity of welded penstock are experimentally verified\\u000a by

Stojan Sedmak; Aleksandar Sedmak

345

MODERATE RESISTANCE TRAINING VOLUME PRODUCES MORE FAVORABLE STRENGTH GAINS THAN HIGH OR LOW VOLUMES DURING A SHORT TERM TRAINING CYCLE  

Microsoft Academic Search

Gonzalez-Badillo, J.J., E.M. Gorostiaga, R. Arellano, and M. Izquierdo. Moderate resistance training volume produces more favorable strength gains than high or low volumes during a short-term training cycle. J. Strength Cond. Res. 19(3):689- 697. 2005.—The purpose of this study was to examine the effects of 3 resistance training volumes on maximal strength in the snatch (Sn), clean & jerk (C&J),

JUAN J. GONZALEZ-BADILLO; ESTEBAN M. GOROSTIAGA; RAUL ARELLANO; MIKEL IZQUIERDO

346

Deep oxidation of methane using catalysts and carriers produced by self-propagating high-temperature synthesis  

Microsoft Academic Search

The self-propagating high-temperature synthesis (SHS) method has been used to produce a range of oxide catalysts which have been found to be active for deep oxidation of methane. The SHS materials studied include various compositions based on the systems Al–Mn–Mg–O, Mg–Cr–O, Mg–Al–O, Mg–Cr–Al–O and Cu–Cr–O with and without the addition of Cerium oxide and an epoxide additive. Specific compositions of

G Xanthopoulou; G Vekinis

2000-01-01

347

High-temperature erosion rates of Fe–Cr–C alloys produced by mechanical alloying and sintering process  

Microsoft Academic Search

In order to develop a material having high erosive wear resistance at elevated temperature, the alloys of the ternary Fe–Cr–C system were produced by mechanical alloying (MA) and sintering process. Three kinds of alloys which have different contents of M23C6 carbide were made, and observation of the microstructure, measurement of the hardness and erosive wear test were carried out on

Noriyuki Hayashi; Kazuhiro Hasezaki; Setsuo Takaki

2000-01-01

348

Nanoscale TiB2-dispersed Cu-matrix composite produced by a high-energy milling and self-propagating high-temperature synthesis process  

Microsoft Academic Search

Nanocomposite Cu-TiB2 powder was in situ synthesized by means of self-propagating high-temperature synthesis (SHS) using high-energy ball milled Ti-B-Cu elemental mixtures as powder precursors. The effect of the preliminary mechanical treatment on the SHS reaction was studied. The size of TiB2 particles produced by SHS was shown to decrease with increasing duration of the preliminary mechanical treatment. Subsequent mechanical treatment

Dina Dudina; Dae-Hwan Kwon; Khoa Xuan Huynh; Thuy Dang Nguyen; Ji-Soon Kim; Young-Soon Kwon

2005-01-01

349

Relativistic effects in radar detection of ionization fronts produced by ultra-high energy cosmic rays  

NASA Astrophysics Data System (ADS)

We revisit the radar echo technique as an approach to detect ultra-high energy cosmic rays (UHECR). The UHECR extensive air showers generate disk-like ionization fronts propagating with a relativistic velocity and creating fast decaying plasma. We study the reflection of a radio wave, such as the one from a radar transmitter or commercial radio and TV station, from the relativistic ionization front. The reflected wave will be frequency upshifted due to the relativistic Doppler effect and propagate almost normally to the front due to relativistic aberration. The amplitude of the reflected wave depends strongly on the front velocity and parameters (density, collision frequency) of the plasma behind the front. We develop a theory that allows one to find the reflected wave. Using this theory and typical parameters of extensive air showers, we discuss the feasibility of UHECR detection.

Bakunov, M. I.; Maslov, A. V.; Novokovskaya, A. L.; Kryemadhi, A.

2010-06-01

350

High-efficiency homologous recombination in the oil-producing alga Nannochloropsis sp.  

PubMed

Algae have reemerged as potential next-generation feedstocks for biofuels, but strain improvement and progress in algal biology research have been limited by the lack of advanced molecular tools for most eukaryotic microalgae. Here we describe the development of an efficient transformation method for Nannochloropsis sp., a fast-growing, unicellular alga capable of accumulating large amounts of oil. Moreover, we provide additional evidence that Nannochloropsis is haploid, and we demonstrate that insertion of transformation constructs into the nuclear genome can occur by high-efficiency homologous recombination. As examples, we generated knockouts of the genes encoding nitrate reductase and nitrite reductase, resulting in strains that were unable to grow on nitrate and nitrate/nitrite, respectively. The application of homologous recombination in this industrially relevant alga has the potential to rapidly advance algal functional genomics and biotechnology. PMID:22123974

Kilian, Oliver; Benemann, Christina S E; Niyogi, Krishna K; Vick, Bertrand

2011-11-28

351

A study of regenerated gratings produced in germanosilicate fibers by high temperature annealing.  

PubMed

In light of recent proposals linking structural change and stresses within regenerated gratings, the details of regeneration of a seed Type-I Bragg grating written in H2 loaded germanosilicate fiber annealed at high temperatures (~900°C) are systematically explored. In particular, the influence of the strength of the grating, the effect of GeO2 doping concentration and the annealing conditions on regeneration are studied. We show that the role of dopants such as Ge and F contribute nothing to the regeneration, consistent with previous results. Rather, they may potentially be detrimental. Strongest regenerated gratings with R ~35% from a 5mm seed grating could be obtained in fibres with the lowest GeO2 concentrations such as standard telecommunications-compatible grade fibre. PMID:21263661

Bandyopadhyay, S; Canning, J; Biswas, P; Stevenson, M; Dasgupta, K

2011-01-17

352

High yield antibiotic producing mutants of Streptomyces erythreus induced by low energy ion implantation  

NASA Astrophysics Data System (ADS)

Conidia of Streptomyces erythreus, an industrial microbe, were implanted by nitrogen ions with energy of 40-60keV and fluence from 1x1011 to 5x1014ions/cm2. The logarithm value of survival fraction had good linear relationship with the logarithm value of fluence. Some mutants with a high yield of erythromycin were induced by ion implantation. The yield increment correlated with the implantation fluence. Compared with the mutation results induced by ultraviolet rays, mutation effects of ion implantation were obvious having higher increasing erythromycin potency and wider mutation spectrum. The spores of Bacillus subtilis were implanted by arsenic ions with energy of 100keV. The distribution of implanted ions was measured by Rutherford Backscatting Spectrometry (RBS) and calculated in theory. The mechanism of mutation induced by ion implantation was discussed.

Chen, Yu; Lin, Zhixin; Zou, Zuyao; Zhang, Feng; Liu, Duo; Liu, Xianghuai; Tang, Jianzhong; Zhu, Weimin; Huang, Bo

1998-05-01

353

A study of high transverse momentum electrons produced inbar pp collisions at 540 GeV  

NASA Astrophysics Data System (ADS)

The production of electrons with very high transverse momentum has been studied in the UA2 experiment at the CERNbar pp collider (sqrt s=540 GeV). From a sample of events containing an electron candidate with p T >15 GeV/c, we extract a clear signal resulting from the production of the charged intermediate vector boson W ±, which subsequently decays into an electron and a neutrino. We study the W production and decay properties. Further-more, we refine our results on the production and decay of the neutral vector boson Z 0. Finally, we compare the experimental results to the predictions of the standard model of the unified electro-weak theory.

Bagnaia, P.; Banner, M.; Battiston, R.; Bloch, Ph.; Bonaudi, F.; Borer, K.; Borghini, M.; Burger, J.; Cenci, P.; Chollet, J.-C.; Clark, A. G.; Conta, C.; Darriulat, P.; di Lella, L.; Dines-Hansch, J.; Dorsaz, P. A.; Engelmann, R.; Fayard, L.; Fraternali, M.; Froidevaux, D.; Fumagalli, G.; Gaillard, J.-M.; Gildemeister, O.; Goggi, V. G.; Gössling, C.; Hahn, B.; Hänni, H.; Hansen, J. R.; Hansen, P.; Harnew, N.; Himel, T.; Hungerbühler, V.; Jenni, P.; Kofoed-Hansen, O.; Lançon, E.; Livan, M.; Loucatos, S.; Madsen, B.; Mani, P.; Mansoulié, B.; Mantovani, G. C.; Mapelli, L.; Merkel, B.; Möllerud, R.; Nilsson, B.; Onions, C.; Parrour, G.; Pastore, F.; Plothow-Besch, H.; Polverel, M.; Repellin, J.-P.; Rimoldi, A.; Rothenberg, A.; Roussarie, A.; Sauvage, G.; Schacher, J.; Siegrist, J. L.; Stimpfl, G.; Stocker, F.; Swartz, M.; Teiger, J.; Tovey, S.; Vercesi, V.; Weidberg, W. R.; Zaccone, H.; Zakrzewski, J. A.; Zeller, W.

1984-03-01

354

Nanometer-size surface features produced by single, low energy, highly charged ions  

SciTech Connect

We have studied the interaction of ions with solid surfaces in the limit of slow, highly charged ions (Xe{sup 44+} 0.1--20 keV/{ital q}). Using atomic force microscopy we are able to see individual ion impact sites on mica, approximately one site per incident ion. Such features are typically circular with {similar_to}20 nm diameter. This damage may be caused by local charge depletion and conversion of the 50 keV Coulomb potential energy of the ions. Contact mode microscopy shows the features to be either pits or blisters depending on scanning direction and force between tip and substrate. By using lateral force microscopy we see the features to be regions of increased friction. The observed surface damage is independent of the ion kinetic energy. Repeated scanning over the same region causes erasure of the observed features. {copyright} {ital 1995} {ital American} {ital Vacuum} {ital Society}

Parks, D.C. [Kansas State University, Manhattan, Kansas 66506-2601 (United States); Bastasz, R.; Schmieder, R.W. [Sandia National Laboratories, Livermore, California 94551-0969 (United States); Stoeckli, M. [Kansas State University, Manhattan, Kansas 66506-2601 (United States)

1995-05-01

355

Gene cloning, heterologous expression, and characterization of a high maltose-producing ?-amylase of Rhizopus oryzae.  

PubMed

A putative ?-amylase gene, designated as RoAmy, was cloned from Rhizopus oryzae. The deduced amino acid sequence showed the highest (42.8%) similarity to the ?-amylase from Trichoderma viride. The RoAmy gene was successfully expressed in Pichia pastoris GS115 under the induction of methanol. The molecular weight of the purified RoAmy determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis was approximately 48 kDa. The optimal pH and temperature were 4-6 and 60 °C, respectively. The enzyme was stable at pH ranges of 4.5-6.5 and temperatures below 50 °C. Purified RoAmy had a K(m) and V(max) of 0.27 mg/ml and 0.068 mg/min, respectively, with a specific activity of 1,123 U/mg on soluble starch. Amylase activity was strongly inhibited by 5 mM Cu(2+) and 5 mM Fe(2+), whereas 5 mM Ca(2+) showed no significant effect. The RoAmy hydrolytic activity was the highest on wheat starch but showed only 55% activity on amylopectin relative to soluble corn starch, while the pullulanase activity was negligible. The main end products of the polysaccharides tested were glucose and maltose. Maltose reached a concentration of 74% (w/w) with potato starch as the substrate. The enzyme had an extremely high affinity (K(m)?=?0.22 mM) to maltotriose. A high ratio of glucose/maltose of 1:4 was obtained when maltotriose was used at an initial concentration of 40 mM. PMID:21243443

Li, Song; Zuo, Zhirui; Niu, Dandan; Singh, Suren; Permaul, Kugenthiren; Prior, Bernard A; Shi, Guiyang; Wang, Zhengxiang

2011-01-18

356

New Crystal-Growth Methods for Producing Lattice-Matched Substrates for High-Temperature Superconductors  

SciTech Connect

This effort addressed the technical problem of identifying and growing, on a commercial scale, suitable single-crystal substrates for the subsequent deposition of epitaxial thin films of high temperature semiconductors such as GaN/AlN. The lack of suitable lattice-matched substrate materials was one of the major problem areas in the development of semiconducting devices for use at elevated temperatures as well as practical opto-electronic devices based on Al- and GaN technology. Such lattice-matched substrates are necessary in order to reduce or eliminate high concentrations of defects and dislocations in GaN/AlN and related epitaxial thin films. This effort concentrated, in particular, on the growth of single crystals of ZnO for substrate applications and it built on previous ORNL experience in the chemical vapor transport growth of large single crystals of zinc oxide. This combined expertise in the substrate growth area was further complemented by the ability of G. Eres and his collaborators to deposit thin films of GaN on the subject substrates and the overall ORNL capability for characterizing the quality of such films. The research effort consisted of research on the growth of two candidate substrate materials in conjunction with concurrent research on the growth and characterization of GaN films, i.e. the effort combined bulk crystal growth capabilities in the area of substrate production at both ORNL and the industrial partner, Commercial Crystal Growth Laboratories (CCL), Naples, Florida, with the novel thin-film deposition techniques previously developed in the ORNL SSD.

Boatner, L.A.

2008-06-24

357

Improving upon Nature: Active site remodeling produces highly efficient aldolase activity towards hydrophobic electrophilic substrates  

PubMed Central

Substrate specificity of enzymes is frequently narrow and constrained by multiple interactions, limiting the use of natural enzymes in biocatalytic applications. Aldolases have important synthetic applications, but the usefulness of these enzymes is hampered by their narrow reactivity profile with unnatural substrates. To explore the determinants of substrate selectivity and alter the specificity of E. coli 2-keto-3-deoxy-6-phosphogluconate (KDPG) aldolase, we employed structure-based mutagenesis coupled with library screening of mutant enzymes localized to the bacterial periplasm. We identified two active site mutations (T161S/S184L) that work additively to enhance the substrate specificity of this aldolase to include catalysis of retro-aldol cleavage of (4S)-2-keto-4-hydroxy-4-(2?-pyridyl)butyrate (S-KHPB). These mutations improve the value of kcat/KMS-KHPB by >450-fold, resulting in a catalytic efficiency that is comparable to that of the wild-type enzyme with the natural substrate while retaining high stereoselectivity. Moreover, the value of kcatS-KHPB for this mutant enzyme, a parameter critical for biocatalytic applications, is 3-fold higher than the maximum value achieved by the natural aldolase with any substrate. This mutant also possesses high catalytic efficiency for the retro-aldol cleavage of the natural substrate, KDPG, and a >50-fold improved activity for cleavage of 2-keto-4-hydroxy-octonoate (KHO), a non-functionalized hydrophobic analog. These data suggest a substrate binding mode that illuminates the origin of facial selectivity in aldol addition reactions catalyzed by KDPG and 2-keto-3-deoxy-6-phosphogalactonate (KDPGal) aldolases. Furthermore, targeting mutations to the active site provides marked improvement in substrate selectivity, demonstrating that structure-guided active site mutagenesis combined with selection techniques can efficiently identify proteins with characteristics that compare favorably to naturally occurring enzymes.

Cheriyan, Manoj; Toone, Eric J.; Fierke, Carol A.

2012-01-01

358

High-resolution mass spectrometric analysis of secondary organic aerosol produced by ozonation of limonene.  

PubMed

Chemical composition of secondary organic aerosol (SOA) formed from the ozone-initiated oxidation of limonene is characterized by high-resolution electrospray ionization mass spectrometry in both positive and negative ion modes. The mass spectra reveal a large number of both monomeric (m/z < 300) and oligomeric (m/z > 300) condensed products of oxidation. A combination of high resolving power (m/Deltam approximately 60,000) and Kendrick mass defect analysis makes it possible to unambiguously determine the molecular composition of hundreds of individual compounds in SOA samples. Van Krevelen analysis shows that the SOA compounds are heavily oxidized, with average O : C ratios of 0.43 and 0.50 determined from the positive and negative ion mode spectra, respectively. A possible reaction mechanism for the formation of the first generation SOA molecular components is considered. The discussed mechanism includes known isomerization and addition reactions of the carbonyl oxide intermediates generated during the ozonation of limonene. In addition, it includes isomerization and decomposition pathways for alkoxy radicals resulting from unimolecular decomposition of carbonyl oxides that have been disregarded by previous studies. The isomerization reactions yield numerous products with a progressively increasing number of alcohol and carbonyl groups, whereas C-C bond scission reactions in alkoxy radicals shorten the carbon chain. Together these reactions yield a large number of isomeric products with broadly distributed masses. A qualitative agreement is found between the number and degree of oxidation of the predicted and measured reaction products in the monomer product range. PMID:18259641

Walser, Maggie L; Desyaterik, Yury; Laskin, Julia; Laskin, Alexander; Nizkorodov, Sergey A

2007-12-10

359

Substrate having high absorptance and emitance black electroless nicel coating and a process for producing the same  

SciTech Connect

A substrate having high absorptance and emittance is produced by roughening the surface of the substrate, immersing the substrate in a first electroless plating bath having a low phosphorus to nickel concentration, then immersing the substrate in a second electroless plating bath having a phosphorus to nickel concentration higher than that of said first electroless plating bath. Thereafter, the resulting electroless nickel-phosphorus alloy coated substrate is immersed in an aqueous acidic etchant bath containing sulfuric acid, nitric acid and divalent nickel to develop a highly blackened surface on said substrate.

Greeson, R.; Geikas, G. I.

1985-04-16

360

LETTER TO THE EDITOR: Line formation of high-intensity ?-Rydberg dielectronic satellites ? in dense laser-produced plasmas  

Microsoft Academic Search

On the basis of experimental and theoretical investigations it is demonstrated for the first time that in cold dense optically thick laser-produced plasmas, created near the target surface, the capture into the He-like ground state 0953-4075\\/31\\/21\\/005\\/img13 is negligible for line formation and that observed high-intensity 0953-4075\\/31\\/21\\/005\\/img14-Rydberg satellite intensities are correlated with highly populated He-like excited states 0953-4075\\/31\\/21\\/005\\/img15. X-ray emission spectra

F. B. Rosmej; A. Ya Faenov; T. A. Pikuz; F. Flora; P. Di Lazzaro; T. Letardi; A. Grilli; A. Reale; L. Palladino; G. Tomassetti; A. Scafati; L. Reale

1998-01-01

361

Traceability, reproducibility, and comparability of grid calibrations  

NASA Astrophysics Data System (ADS)

The national metrology institute of Germany, PTB, offers traceable, two-dimensional pattern placement calibrations of microstructures on masks. Whereas the measurement uncertainty for the calibrated pattern positions in terms of traceable coordinate values is only comparable to the position tolerances actually required for mask patterning, i.e. about 35 nm, the deviations from the design grid can be determined with smaller uncertainties. In calibration certificates offered by PTB, these differences are taken into account and the uncertainties for the length of the grid and the uncertainties for the position deviations from the design grid are quoted separately as 30 nm and 10 nm respectively. Developments to further reduce the uncertainties are under way. An analysis of photomask recalibration results shows the long-term reproducibility of PTB length calibrations to be better than 15 nm or 1*10-7, including substrate stability effects. Details of the recalibration results will be given. Leica Microsystems Lithography runs a laboratory for two-dimensional pattern placement calibrations, formally accredited by PTB within DKD, the German calibration service. Results of recent comparison measurements between the DKD laboratory and PTB on masks of different size will be given and discussed as an example of the process of dissemination of the length unit to industry.

Bosse, Harald; Haessler-Grohne, Wolfgang; Brendel, Bernd

1999-12-01

362

Accel-Decel method of producing high-Q low velocity ions  

SciTech Connect

The double EN tandem Van de Graaff accelerators at the University of Pittsburgh's Nuclear Physics Laboratory have been used in part since 1978, operating in the 3-stage mode, as a source of highly stripped but low velocity ions for experiments of interest to atomic physics. Much of the work has involved investigating the technical details of this new accel-decel technique and gaining practical experience in operating the accelerators in the accel-decel mode. Decelerations to a final energy factor of approx. = 50 less than the stripping energy have been achieved for fully stripped oxygen ions and some charge exchange measurements on He published, demonstrating the potential of the accel-decel technique for supplying atomic physics with data from a previously unattainable energy and charge state regime. Practical problems encountered and the technical developments leading to these first prototype experiments will be reviewed. Subsequent developmental work, the present status of the project, and future technical plans at Pittsburgh are summarized. Finally, the future possibilities of the accel-decel technique generally are discussed.

Saylor, T.K.; Bayfield, J.E.; Gardner, L.D.; Gulkok, Y.Z.; Sharma, S.D.

1981-04-01

363

Rhodotorula mucilaginosa, a carotenoid producing yeast strain from a Patagonian high-altitude lake.  

PubMed

The red yeast Rhodotorula mucilaginosa strain CRUB 0138 (previously identified as R. lactosa) was isolated from a high-altitude Patagonian Lake Toncek (1700 m a.s.l.), and assigned with mucilaginosa species. Its biochemical, physiological and molecular features were assessed and compared to R. mucilaginosa PYCC 5166 type strain using a polyphasic approach; in addition, biomass and carotenoid pigment production at different C/N ratios were determined in an incubator shaker. Phenetic characterization by means of 70 current physiological tests including assimilation of aldaric acids and aromatic compounds, and also the ability to grow with amino acids as sole carbon sources, was carried out. According to numerical taxonomy calculations, similarity indexes between R. mucilaginosa CRUB 0138 and PYCC 5166 type strain were 0.86 and 0.77, corresponding to a complete set of physiological tests and MSP-PCR (Mini/Micro Satellite Primed PCR; (GTG)5, M13 and (GAC)5 primers were employed) fingerprinting. Killer activity against 2 native strains, Rhodosporidium kratochvilovae and R. mucilaginosa was detected. Maximum biomass-glucose conversion efficiency (87%) and maximum carotenoid yield (2.32 mg/L) were obtained at C/N = 5 in culture medium containing 10 and 40 g/L glucose, respectively. Different C/N ratios did not influence carotenoid pigment production but low C/N enhanced biomass yield. PMID:15143736

Libkind, D; Brizzio, S; van Broock, M

2004-01-01

364

High Quality but Limited Quantity Perceptual Evidence Produces Neural Accumulation in Frontal and Parietal Cortex  

PubMed Central

Goal-directed perceptual decisions involve the analysis of sensory inputs, the extraction and accumulation of evidence, and the commitment to a choice. Previous neuroimaging studies of perceptual decision making have identified activity related to accumulation in parietal, inferior temporal, and frontal regions. However, such effects may be related to factors other than the integration of evidence over time, such as changes in the quantity of stimulus input and in attentional demands leading up to a decision. The current study tested an accumulation account using 2 manipulations. First, to test whether patterns of accumulation can be explained by changes in the quantity of sensory information, objects were revealed with a high quality but consistent quantity of evidence throughout the trial. Imaging analysis revealed patterns of accumulation in frontal and parietal regions but not in inferior temporal regions. This result supports a framework in which evidence is processed in sensory cortex and integrated over time in higher order cortical areas. Second, to test whether accumulation signals are driven by attentional demands, task difficulty was increased on some trials. This manipulation did not affect the nature of accumulating functional magnetic resonance imaging signals, indicating that accumulating signals are not necessarily driven by changes in attentional demand.

Ploran, Elisabeth J.; Tremel, Joshua J.; Nelson, Steven M.

2011-01-01

365

Combined effect of noise and vibration produced by high-speed trains on annoyance in buildings.  

PubMed

The effects of noise and vibration on annoyance in buildings during the passage of a nearby high-speed train have been investigated in a laboratory experiment with recorded train noise and 20 Hz vibration. The noises included the effects of two types of fac?ade: windows-open and windows-closed. Subjects were exposed to six levels of noise and six magnitudes of vibration, and asked to rate annoyance using an 11-point numerical scale. The experiment consisted of four sessions: (1) evaluation of noise annoyance in the absence of vibration, (2) evaluation of total annoyance from simultaneous noise and vibration, (3) evaluation of noise annoyance in the presence of vibration, and (4) evaluation of vibration annoyance in the absence of noise. The results show that vibration did not influence ratings of noise annoyance, but that total annoyance caused by combined noise and vibration was considerably greater than the annoyance caused by noise alone. The noise annoyance and the total annoyance caused by combined noise and vibration were associated with subject self-ratings of noise sensitivity. Two classical models of total annoyance due to combined noise sources (maximum of the single source annoyance or the integration of individual annoyance ratings) provided useful predictions of the total annoyance caused by simultaneous noise and vibration. PMID:23556582

Lee, Pyoung Jik; Griffin, Michael J

2013-04-01

366

System for producing a regulated atmosphere for a high-temperature process  

SciTech Connect

A system is described for providing a regulated atmosphere for a high temperature furnace, the system comprising: (a) startup heater means, connected to a source of a first fluid, for vaporizing the first fluid when the apparatus is initially activated, (b) heat exchange means, connected to receive the vaporized first fluid from the startup heater means, (c) a dissociation heater, the dissociation heater being located outside of the furnace, and being connected to receive fluid from the heat exchange means. The dissociation heater is the sole means of dissociation of the fluid into combustible components. The output of the dissociation heater is connected to convey dissociated fluid into the heat exchange means, whereby incoming fluid entering the heat exchange means can be vaporized by the heat provided from the output of the dissociation heater, (d) means for mixing the dissociated first fluid with a diluting fluid, the diluting fluid being substantially inert at the temperatures present in the furnace, (e) means for measuring the proportion of one or more of the combustible components, in the mixture of fluids, and (f) means for regulating the flow of the diluting fluid into the mixing means, in response to the measured proportion of combustibles.

Brahmbhatt, S.R.

1987-02-17

367

Ablation produced using a toroidal High Intensity Focused Ultrasound device is independent of hepatic perfusion  

NASA Astrophysics Data System (ADS)

In the liver, the efficacy of radiofrequency or HIFU ablation is impaired by blood perfusion. This can be overcome by hepatic inflow occlusion using a Pringle manoeuver. Here we report the in vivo evaluation of ablations performed in the liver using a surgical toroidal High Intensity Focused Ultrasound (HIFU) device used during an open procedure with and without hepatic inflow occlusion. The HIFU device was composed of 256 toroidal-shaped emitters working at 3 MHz and an integrated ultrasound imaging probe working at 7.5 MHz. Using an Intermittent Pringle Manoeuver (IPM), thermal ablations were created in three pigs with hepatic inflow occlusion (IPM Group) and in three pigs with normal perfusion (NoIPM Group). The ablations were studied on sonograms, macroscopically and microscopically fourteen days after the treatment. In the NoIPM group, the average coagulated volume obtained after a 40 s total exposure was 7.4+/-3.8 cm3 (2.2-16.6). In the IPM group, the average ablated volume was 6.3+/-2.9 cm3 (2.6-12.1). There was no significant difference between the two groups in terms of ablated volume (p = 0.25), diameter (p = 0.37), or depth (p = 0.61). The data from the present study demonstrated that there is no significant influence of hepatic vascular flow on the size and shape of ablations created with the toroidal-shaped HIFU device that has been used. The HIFU approach presented in this study is characterized by the brevity of the treatment (40 seconds for one ablation of 7 cm3), which makes it possible to reduce treatment dependence on blood perfusion. Ablations obtained with or without a Pringle manoeuver were homogeneous in both groups and were not significantly different in terms of diameter, depth and volumes in the IPM group compared with the NoIPM group.

Melodelima, David; N'djin, William A.; Favre, Julia; Parmentier, Hubert; Rivoire, Michel; Chapelon, Jean Yves

2011-09-01

368

High Strength and High Ductility of Ultrafine-Grained, Interstitial-Free Steel Produced by ECAE and Annealing  

NASA Astrophysics Data System (ADS)

Interstitial-free steel (IF steel) underwent severe plastic deformation by equal-channel angular extrusion/pressing (ECAE/P) to improve its strength, and then it was annealed to achieve a good strength-ductility balance. The coarse-grained microstructure of IF steel was refined down to the submicron level after eight-pass ECAE. The ultrafine-grained (UFG) microstructure with high dislocation density brought about substantially improved strength but limited tensile ductility. The limited ductility was attributed to the small, uniform elongation caused by early plastic instability. The annealing at temperatures below 723 K (450 °C) for 1 hour did not lead to remarkable softening, whereas annealing at temperatures up to 923 K (650 °C) resulted in complete softening depending on the development of recrystallization. Therefore, the temperature of approximately 923 K (650 °C) can be considered as a critical recrystallization temperature for UFG IF steel. The annealing at 873 K (600 °C) for different time intervals resulted in different stress-strain response. Uniform tensile elongation increased at the expense of strength with annealing time intervals. After annealing at 873 K (600 °C) for 60 minutes, the yield strength, tensile strength, uniform elongation, and total elongation were found to be 320 MPa, 485 MPa, 15.1 pct, and 33.7 pct, respectively, showing the better combination of strength and ductility compared with cold-rolled samples.

Purcek, Gencaga; Saray, Onur; Karaman, Ibrahim; Maier, Hans J.

2012-06-01

369

Potato and high-amylose maize starches are not equivalent producers of butyrate for the colonic mucosa.  

PubMed

Portal appearance of short-chain fatty acids (SCFA) produced from fermentation of three different resistant starch (RS) sources (raw potato starch, high-amylose maize starch and retrograded high-amylose maize starch) was investigated in pigs. The catheterization technique coupled with determination of portal blood flow was used to estimate SCFA uptake by the colonic mucosa. Our hypothesis was that these three RS were not equivalent butyrate providers for the colonic mucosa and that butyrate uptake would therefore be different after in vivo fermentation of each starch. The starches induced different patterns of appearance of SCFA in the portal blood; raw potato starch was the only RS source to show a significant appearance of butyrate in the portal blood. Thus, uptake of butyrate by the colonic mucosa apparently differed between starches. This finding suggests that butyrate uptake does not only depend on the flow of butyrate appearing in the lumen. Indeed, for unexplained reasons, utilization of butyrate by the colonic mucosa appeared to be less efficient when the butyrate was produced from fermentation of potato starch than when it was produced from fermentation of the other RS sources. PMID:11177182

Martin, L J; Dumon, H J; Lecannu, G; Champ, M M

2000-11-01

370

Classification of thoracic and lumbar spine fractures: problems of reproducibility  

Microsoft Academic Search

Reproducibility of fracture classification systems in general has been a matter of controversy. The reproducibility of spinal fracture classifications has not been sufficiently studied. We studied the inter-observer and intra-observer reproducibility of the Magerl (AO) classification using radiograms, CTs and MRIs of 53 patients. We compared this classification with the older and simpler Denis classification. Five observers classified the fractures,

F. C. Oner; L. M. P. Ramos; R. K. J. Simmermacher; P. T. D. Kingma; C. H. Diekerhof; W. J. A. Dhert; A. J. Verbout

2002-01-01

371

Metabolic profiles in five high-producing Swedish dairy herds with a history of abomasal displacement and ketosis  

PubMed Central

Background Body condition score and blood profiles have been used to monitor management and herd health in dairy cows. The aim of this study was to examine BCS and extended metabolic profiles, reflecting both energy metabolism and liver status around calving in high-producing herds with a high incidence of abomasal displacement and ketosis and to evaluate if such profiles can be used at herd level to pinpoint specific herd problems. Methods Body condition score and metabolic profiles around calving in five high-producing herds with high incidences of abomasal displacement and ketosis were assessed using linear mixed models (94 cows, 326 examinations). Cows were examined and blood sampled every three weeks from four weeks ante partum (ap) to nine weeks postpartum (pp). Blood parameters studied were glucose, fructosamine, non-esterified fatty acids (NEFA), insulin, ?-hydroxybutyrate, aspartate aminotransferase, glutamate dehydrogenase, haptoglobin and cholesterol. Results All herds had overconditioned dry cows that lost body condition substantially the first 4–6 weeks pp. Two herds had elevated levels of NEFA ap and three herds had elevated levels pp. One herd had low levels of insulin ap and low levels of cholesterol pp. Haptoglobin was detected pp in all herds and its usefulness is discussed. Conclusion NEFA was the parameter that most closely reflected the body condition losses while these losses were not seen in glucose and fructosamine levels. Insulin and cholesterol were potentially useful in herd profiles but need further investigation. Increased glutamate dehydrogenase suggested liver cell damage in all herds.

Stengarde, Lena; Traven, Madeleine; Emanuelson, Ulf; Holtenius, Kjell; Hultgren, Jan; Niskanen, Rauni

2008-01-01

372

An accurate and reproducible method for proteome profiling of the effects of salt stress in the rice leaf lamina  

Microsoft Academic Search

Proteomic analysis of any biological system by two- dimensional gel electrophoresis (2-DE) requires high resolution and high reproducibility. The results pre- sented here demonstrate the reproducible and accu- rate separation of rice (Oryza sativa L.) proteins using improved procedures for high resolution 2-DE, which were adapted for the separation of rice lamina proteins. Validation of this system was achieved by

Robert Parker; Timothy J. Flowers; Anthony L. Moore; Nicholas V. J. Harpham

2006-01-01

373

Psychophysiological responses to pain identify reproducible human clusters.  

PubMed

Pain is a ubiquitous yet highly variable experience. The psychophysiological and genetic factors responsible for this variability remain unresolved. We hypothesised the existence of distinct human pain clusters (PCs) composed of distinct psychophysiological and genetic profiles coupled with differences in the perception and the brain processing of pain. We studied 120 healthy subjects in whom the baseline personality and anxiety traits and the serotonin transporter-linked polymorphic region (5-HTTLPR) genotype were measured. Real-time autonomic nervous system parameters and serum cortisol were measured at baseline and after standardised visceral and somatic pain stimuli. Brain processing reactions to visceral pain were studied in 29 subjects using functional magnetic resonance imaging (fMRI). The reproducibility of the psychophysiological responses to pain was assessed at 1year. In group analysis, visceral and somatic pain caused an expected increase in sympathetic and cortisol responses and activated the pain matrix according to fMRI studies. However, using cluster analysis, we found 2 reproducible PCs: at baseline, PC1 had higher neuroticism/anxiety scores (P?0.01); greater sympathetic tone (P<0.05); and higher cortisol levels (P?0.001). During pain, less stimulus was tolerated (P?0.01), and there was an increase in parasympathetic tone (P?0.05). The 5-HTTLPR short allele was over-represented (P?0.005). PC2 had the converse profile at baseline and during pain. Brain activity differed (P?0.001); greater activity occurred in the left frontal cortex in PC1, whereas PC2 showed greater activity in the right medial/frontal cortex and right anterior insula. In health, 2 distinct reproducible PCs exist in humans. In the future, PC characterization may help to identify subjects at risk for developing chronic pain and may reduce variability in brain imaging studies. PMID:23714265

Farmer, Adam D; Coen, Steven J; Kano, Michiko; Paine, Peter A; Shwahdi, Mustafa; Jafari, Jafar; Kishor, Jessin; Worthen, Sian F; Rossiter, Holly E; Kumari, Veena; Williams, Steven C R; Brammer, Michael; Giampietro, Vincent P; Droney, Joanne; Riley, Julia; Furlong, Paul L; Knowles, Charles H; Lightman, Stafford L; Aziz, Qasim

2013-05-25

374

Reproducibility and quantitation of amplicon sequencing-based detection.  

PubMed

To determine the reproducibility and quantitation of the amplicon sequencing-based detection approach for analyzing microbial community structure, a total of 24 microbial communities from a long-term global change experimental site were examined. Genomic DNA obtained from each community was used to amplify 16S rRNA genes with two or three barcode tags as technical replicates in the presence of a small quantity (0.1% wt/wt) of genomic DNA from Shewanella oneidensis MR-1 as the control. The technical reproducibility of the amplicon sequencing-based detection approach is quite low, with an average operational taxonomic unit (OTU) overlap of 17.2%±2.3% between two technical replicates, and 8.2%±2.3% among three technical replicates, which is most likely due to problems associated with random sampling processes. Such variations in technical replicates could have substantial effects on estimating ?-diversity but less on ?-diversity. A high variation was also observed in the control across different samples (for example, 66.7-fold for the forward primer), suggesting that the amplicon sequencing-based detection approach could not be quantitative. In addition, various strategies were examined to improve the comparability of amplicon sequencing data, such as increasing biological replicates, and removing singleton sequences and less-representative OTUs across biological replicates. Finally, as expected, various statistical analyses with preprocessed experimental data revealed clear differences in the composition and structure of microbial communities between warming and non-warming, or between clipping and non-clipping. Taken together, these results suggest that amplicon sequencing-based detection is useful in analyzing microbial community structure even though it is not reproducible and quantitative. However, great caution should be taken in experimental design and data interpretation when the amplicon sequencing-based detection approach is used for quantitative analysis of the ?-diversity of microbial communities. PMID:21346791

Zhou, Jizhong; Wu, Liyou; Deng, Ye; Zhi, Xiaoyang; Jiang, Yi-Huei; Tu, Qichao; Xie, Jianping; Van Nostrand, Joy D; He, Zhili; Yang, Yunfeng

2011-02-24

375

Compositional, nutritional, and functional characteristics of instant teas produced from low- and high-quality black teas.  

PubMed

Two types of instant teas produced from low- and high-quality black teas were examined for their proximate composition, dietary fiber, minerals, water-soluble vitamins, total phenolic content, various antioxidant assays, phenolics (flavanols, condensed phenolics, and phenolic acids), alkaloids, and carotenoids as well as taste-active compounds (sugars, organic acids, and free amino acids). Some variations, albeit to different extents, were observed (p < 0.05) among these parameters between instant teas produced from low- and high-quality black teas. With respect to proximate composition, carbohydrate was the predominant component (56.68-59.84 g/100 g), followed by protein (19.31-19.86 g/100 g). Ash, moisture, and, to a lesser extent, dietary fiber and fat were also present in both instant teas. Thirteen minerals, four water-soluble vitamins, six flavanols, two alkaloids, three condensed phenolics, one phenolic acid, and one carotenoid were identified. Total phenolic content varied between 17.35 and 17.82 g of gallic acid equivalents (GAE)/100 g instant tea. With regard to antioxidant activities, three different assays such as oxygen radical absorbance capacity (ORAC), trolox equivalent antioxidant capacity (TEAC), and cupric ion reducing antioxidant capacity (CUPRAC) were measured. No significant differences (p > 0.05) in total phenolic, ORAC, TEAC, and CUPRAC contents between low- and high-quality instant teas were observed. With regard to taste-active compounds, 3 sugars, 5 organic acids, and 18 free amino acids were positively identified, of which fructose, tannic acid, and theanine predominated, respectively. The present work suggests that despite some differences, instant teas produced from low- and high-quality black teas should not be distinguished on the basis of their compositional, nutritional, and functional characteristics as well as taste-active compounds. PMID:23837397

Alasalvar, Cesarettin; Pelvan, Ebru; Ozdemir, Kübra Sultan; Kocada?l?, Tolgahan; Mogol, Burçe Ataç; Pasl?, Ayça Ayfer; Ozcan, Nihat; Ozçelik, Beraat; Gökmen, Vural

2013-07-23

376

Reproducibility of pacing profiles in competitive swimmers.  

PubMed

This study aimed at determining the reproducibility of pacing profiles (PP) during simulated swimming trials as well as the comparison between simulated and real competitions (RC). Sixteen competitive front crawl swimmers (7 females, 9 males) performed 2 × 200 m, 2 × 400 m and 2 × 800 m tests, each test 7 days apart. All 100 m split (ST) and total times (TT) were recorded (additionally 50 m ST for the 200 m bouts). The PP of one RC within a maximum of 8 weeks before or after data acquisition was used for comparison. No difference was observed between test and retest for TT (p<0.16). Coefficients of variation (CV) for all ST during 800 m were between 0.9 and 1.8% (standard error of measurement (SEM)=0.6-2.1 s), except for the last 2 sections (CV=2.5% and 2.9%). During 400 m and 200 m, CV was below 1.7% for each section (SEM=0.4-1.7 s). Mean differences between test and retest ranged from 1.8 s (Cl: 0.1-3.4 s) in the 400 m bouts to 4.1 s (Cl: 1.3-9.5 s) for the 800 m races. Although section times were faster during all sections of RC compared to SC, PP was similar during both trials (p>0.22). However, swimmers were faster in each section during RC. In conclusion, PP seem stable, at least during the first three quarters of the race. Furthermore, simulated trials seem to be an acceptable model to analyse PP in competitive swimming. PMID:22972249

Skorski, S; Faude, O; Rausch, K; Meyer, T

2012-09-12

377

Is My Network Module Preserved and Reproducible?  

PubMed Central

In many applications, one is interested in determining which of the properties of a network module change across conditions. For example, to validate the existence of a module, it is desirable to show that it is reproducible (or preserved) in an independent test network. Here we study several types of network preservation statistics that do not require a module assignment in the test network. We distinguish network preservation statistics by the type of the underlying network. Some preservation statistics are defined for a general network (defined by an adjacency matrix) while others are only defined for a correlation network (constructed on the basis of pairwise correlations between numeric variables). Our applications show that the correlation structure facilitates the definition of particularly powerful module preservation statistics. We illustrate that evaluating module preservation is in general different from evaluating cluster preservation. We find that it is advantageous to aggregate multiple preservation statistics into summary preservation statistics. We illustrate the use of these methods in six gene co-expression network applications including 1) preservation of cholesterol biosynthesis pathway in mouse tissues, 2) comparison of human and chimpanzee brain networks, 3) preservation of selected KEGG pathways between human and chimpanzee brain networks, 4) sex differences in human cortical networks, 5) sex differences in mouse liver networks. While we find no evidence for sex specific modules in human cortical networks, we find that several human cortical modules are less preserved in chimpanzees. In particular, apoptosis genes are differentially co-expressed between humans and chimpanzees. Our simulation studies and applications show that module preservation statistics are useful for studying differences between the modular structure of networks. Data, R software and accompanying tutorials can be downloaded from the following webpage: http://www.genetics.ucla.edu/labs/horvath/CoexpressionNetwork/ModulePreservation.

Langfelder, Peter; Luo, Rui; Oldham, Michael C.; Horvath, Steve

2011-01-01

378

High-order harmonic generation in a plasma plume of in situ laser-produced silver nanoparticles  

SciTech Connect

The results of the experimental study of high-order harmonic generation (HHG) from the interaction of 45-fs Ti:sapphire laser pulses with plasma plumes of Ag nanoparticles produced in situ are presented in this article. The nanoparticles were generated by the interaction of 300-ps, 20-mJ laser pulses with bulk silver targets at an intensity of {approx}1x10{sup 13} W/cm{sup 2}. The spectral characteristics of the HHG from nanoparticles produced in situ are compared with the HHG from monoparticle plasma plumes and with the HHG from preformed nanoparticle-containing plasma plumes. The cutoff harmonic order generated using the in situ silver nanoparticles is at the 21st harmonic order.

Singhal, H.; Naik, P. A.; Chakera, J. A.; Chakravarty, U.; Vora, H. S.; Srivastava, A. K.; Mukherjee, C.; Navathe, C. P.; Deb, S. K.; Gupta, P. D. [Raja Ramanna Centre for Advanced Technology, Indore 452 013 (India); Ganeev, R. A. [Raja Ramanna Centre for Advanced Technology, Indore 452 013 (India); Institute of Electronics, 33, Dormon Yoli street, Tashkent 100125 (Uzbekistan)

2010-10-15

379

High prevalence of CTX-M-15-producing O25b-ST131 Escherichia coli clone in Bulgarian hospitals.  

PubMed

According to the European Antimicrobial Resistance Surveillance System project results, Bulgaria has become one of the European countries with dramatically increasing rates of extended-spectrum beta-lactamase (ESBL) producers. The aim of this work was to investigate the epidemiology of ESBL-producing Escherichia coli clinical isolates in Bulgaria, collected from seven clinical centers in three towns, during two study periods: 2002-2003 and 2006-2009. For 193 ESBL-producing E. coli isolates random amplified polymorphic DNA (RAPD) analyses, phylogenetic typing, and screening for O25b-ST131 isolates were carried out. Antimicrobial susceptibility, ESBL-type and transferability of resistance determinants were analyzed. Four different ESBL-types, namely TEM-139, SHV-12, CTX-M-3, and CTX-M-15 were found. CTX-M-15 dominated, being found in 88% of the isolates. RAPD-typing revealed 35 types, among which type A dominated, comprising 65% of the isolates. Sixty-eight percent of the 193 isolates belonged to the O25b-ST131 clone, to the phylogenetic group B2, mostly showed RAPD-type A (92%) and were found in all participating hospitals. O25b-ST131 isolates predominantly produced CTX-M-15 (96%), and less SHV-12 (n=3) or TEM-139 (n=2). In conclusion, this study demonstrated for the first time the country-wide dissemination of a highly resistant B2 O25b-ST131 CTX-M-15 producing E. coli clone in Bulgaria. PMID:22352448

Markovska, Rumyana; Schneider, Ines; Ivanova, Dobrinka; Keuleyan, Emma; Stoeva, Temenuga; Sredkova, Mariya; Markova, Boyka; Bojkova, Kalina; Gergova, Raina; Bauernfeind, Adolf; Mitov, Ivan

2012-02-21

380

Comparable high rates of extended-spectrum-beta-lactamase-producing Escherichia coli in birds of prey from Germany and Mongolia.  

PubMed

Frequent contact with human waste and liquid manure from intensive livestock breeding, and the increased loads of antibiotic-resistant bacteria that result, are believed to be responsible for the high carriage rates of ESBL-producing E. coli found in birds of prey (raptors) in Central Europe. To test this hypothesis against the influence of avian migration, we initiated a comparative analysis of faecal samples from wild birds found in Saxony-Anhalt in Germany and the Gobi-Desert in Mongolia, regions of dissimilar human and livestock population characteristics and agricultural practices. We sampled a total of 281 wild birds, mostly raptors with primarily north-to-south migration routes. We determined antimicrobial resistance, focusing on ESBL production, and unravelled the phylogenetic and clonal relatedness of identified ESBL-producing E. coli isolates using multi-locus sequence typing (MLST) and macrorestriction analyses. Surprisingly, the overall carriage rates (approximately 5%) and the proportion of ESBL-producers among E. coli (Germany: 13.8%, Mongolia: 10.8%) were similar in both regions. Whereas bla(CTX-M-1) predominated among German isolates (100%), bla(CTX-M-9) was the most prevalent in Mongolian isolates (75%). We identified sequence types (STs) that are well known in human and veterinary clinical ESBL-producing E. coli (ST12, ST117, ST167, ST648) and observed clonal relatedness between a Mongolian avian ESBL-E. coli (ST167) and a clinical isolate of the same ST that originated in a hospitalised patient in Europe. Our data suggest the influence of avian migratory species in the transmission of ESBL-producing E. coli and challenge the prevailing assumption that reducing human influence alone invariably leads to lower rates of antimicrobial resistance. PMID:23300857

Guenther, Sebastian; Aschenbrenner, Katja; Stamm, Ivonne; Bethe, Astrid; Semmler, Torsten; Stubbe, Annegret; Stubbe, Michael; Batsajkhan, Nyamsuren; Glupczynski, Youri; Wieler, Lothar H; Ewers, Christa

2012-12-31

381

Comparable High Rates of Extended-Spectrum-Beta-Lactamase-Producing Escherichia coli in Birds of Prey from Germany and Mongolia  

PubMed Central

Frequent contact with human waste and liquid manure from intensive livestock breeding, and the increased loads of antibiotic-resistant bacteria that result, are believed to be responsible for the high carriage rates of ESBL-producing E. coli found in birds of prey (raptors) in Central Europe. To test this hypothesis against the influence of avian migration, we initiated a comparative analysis of faecal samples from wild birds found in Saxony-Anhalt in Germany and the Gobi-Desert in Mongolia, regions of dissimilar human and livestock population characteristics and agricultural practices. We sampled a total of 281 wild birds, mostly raptors with primarily north-to-south migration routes. We determined antimicrobial resistance, focusing on ESBL production, and unravelled the phylogenetic and clonal relatedness of identified ESBL-producing E. coli isolates using multi-locus sequence typing (MLST) and macrorestriction analyses. Surprisingly, the overall carriage rates (approximately 5%) and the proportion of ESBL-producers among E. coli (Germany: 13.8%, Mongolia: 10.8%) were similar in both regions. Whereas blaCTX-M-1 predominated among German isolates (100%), blaCTX-M-9 was the most prevalent in Mongolian isolates (75%). We identified sequence types (STs) that are well known in human and veterinary clinical ESBL-producing E. coli (ST12, ST117, ST167, ST648) and observed clonal relatedness between a Mongolian avian ESBL-E. coli (ST167) and a clinical isolate of the same ST that originated in a hospitalised patient in Europe. Our data suggest the influence of avian migratory species in the transmission of ESBL-producing E. coli and challenge the prevailing assumption that reducing human influence alone invariably leads to lower rates of antimicrobial resistance.

Guenther, Sebastian; Aschenbrenner, Katja; Stamm, Ivonne; Bethe, Astrid; Semmler, Torsten; Stubbe, Annegret; Stubbe, Michael; Batsajkhan, Nyamsuren; Glupczynski, Youri; Wieler, Lothar H.; Ewers, Christa

2012-01-01

382

Potential for green microalgae to produce hydrogen, pharmaceuticals and other high value products in a combined process  

PubMed Central

Green microalgae for several decades have been produced for commercial exploitation, with applications ranging from health food for human consumption, aquaculture and animal feed, to coloring agents, cosmetics and others. Several products from green algae which are used today consist of secondary metabolites that can be extracted from the algal biomass. The best known examples are the carotenoids astaxanthin and ?-carotene, which are used as coloring agents and for health-promoting purposes. Many species of green algae are able to produce valuable metabolites for different uses; examples are antioxidants, several different carotenoids, polyunsaturated fatty acids, vitamins, anticancer and antiviral drugs. In many cases, these substances are secondary metabolites that are produced when the algae are exposed to stress conditions linked to nutrient deprivation, light intensity, temperature, salinity and pH. In other cases, the metabolites have been detected in algae grown under optimal conditions, and little is known about optimization of the production of each product, or the effects of stress conditions on their production. Some green algae have shown the ability to produce significant amounts of hydrogen gas during sulfur deprivation, a process which is currently studied extensively worldwide. At the moment, the majority of research in this field has focused on the model organism, Chlamydomonas reinhardtii, but other species of green algae also have this ability. Currently there is little information available regarding the possibility for producing hydrogen and other valuable metabolites in the same process. This study aims to explore which stress conditions are known to induce the production of different valuable products in comparison to stress reactions leading to hydrogen production. Wild type species of green microalgae with known ability to produce high amounts of certain valuable metabolites are listed and linked to species with ability to produce hydrogen during general anaerobic conditions, and during sulfur deprivation. Species used today for commercial purposes are also described. This information is analyzed in order to form a basis for selection of wild type species for a future multi-step process, where hydrogen production from solar energy is combined with the production of valuable metabolites and other commercial uses of the algal biomass.

2013-01-01

383

Multi-Parametric Neuroimaging Reproducibility: A 3T Resource Study  

PubMed Central

Modern MRI image processing methods have yielded quantitative, morphometric, functional, and structural assessments of the human brain. These analyses typically exploit carefully optimized protocols for specific imaging targets. Algorithm investigators have several excellent public data resources to use to test, develop, and optimize their methods. Recently, there has been an increasing focus on combining MRI protocols in multi-parametric studies. Notably, these have included innovative approaches for fusing connectivity inferences with functional and/or anatomical characterizations. Yet, validation of the reproducibility of these interesting and novel methods has been severely hampered by the limited availability of appropriate multi-parametric data. We present an imaging protocol optimized to include state-of-the-art assessment of brain function, structure, micro-architecture, and quantitative parameters within a clinically feasible 60 minute protocol on a 3T MRI scanner. We present scan-rescan reproducibility of these imaging contrasts based on 21 healthy volunteers (11 M/10 F, 22–61 y/o). The cortical gray matter, cortical white matter, ventricular cerebrospinal fluid, thalamus, putamen, caudate, cerebellar gray matter, cerebellar white matter, and brainstem were identified with mean volume-wise reproducibility of 3.5%. We tabulate the mean intensity, variability and reproducibility of each contrast in a region of interest approach, which is essential for prospective study planning and retrospective power analysis considerations. Anatomy was highly consistent on structural acquisition (~1–5% variability), while variation on diffusion and several other quantitative scans was higher (~<10%). Some sequences are particularly variable in specific structures (ASL exhibited variation of 28% in the cerebral white matter) or in thin structures (quantitative T2 varied by up to 73% in the caudate) due, in large part, to variability in automated ROI placement. The richness of the joint distribution of intensities across imaging methods can be best assessed within the context of a particular analysis approach as opposed to a summary table. As such, all imaging data and analysis routines have been made publicly and freely available. This effort provides the neuroimaging community with a resource for optimization of algorithms that exploit the diversity of modern MRI modalities. Additionally, it establishes a baseline for continuing development and optimization of multi-parametric imaging protocols.

Landman, Bennett A.; Huang, Alan J.; Gifford, Aliya; Vikram, Deepti S.; Lim, Issel Anne L.; Farrell, Jonathan A.D.; Bogovic, John A.; Hua, Jun; Chen, Min; Jarso, Samson; Smith, Seth A.; Joel, Suresh; Mori, Susumu; Pekar, James J.; Barker, Peter B.; Prince, Jerry L.; van Zijl, Peter C.M.

2010-01-01

384

Reproducible, rugged, and inexpensive photocathode x-ray diode  

SciTech Connect

The photoemissive cathode type of x-ray diode (XRD) is popular for measuring time and spectrally resolved output of pulsed power experiments. Vitreous carbon XRDs currently used on the Sandia National Laboratories Z-machine were designed in the early 1980s and use materials and processes no longer available. Additionally cathodes used in the high x-ray flux and dirty vacuum environment of a machine such as Z suffer from response changes requiring recalibration. In searching for a suitable replacement cathode, we discovered very high purity vitreous-carbon planchets are commercially available for use as biological substrates in scanning electron microscope (SEM) work. After simplifying the photocathode mounting to use commercially available components, we constructed a set of 20 XRDs using SEM planchets that were then calibrated at the National Synchrotron Light Source at Brookhaven National Laboratory. We present comparisons of the reproducibility and absolute calibrations between the current vitreous-carbon XRDs and our new design.

Idzorek, G. C.; Tierney, T. E.; Lockard, T. E. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Moy, K. J. [NSTec, Las Vegas, Nevada 89193 (United States); Keister, J. W. [SFA, Inc. Brookhaven National Laboratory, Upton, New York 11973 (United States)

2008-10-15

385

Neutron-deficient N{approx_equal}126 nuclei produced in 238U fragmentation: population of high-spin states  

SciTech Connect

The population of metastable states produced in relativistic-energy fragmentation of a 238U beam has been measured. For states with high angular momentum, I=17({Dirac_h}/2{pi}) and I=21.5({Dirac_h}/2{pi}), a higher population than expected has been observed, with the discrepancy increasing with angular momentum. By considering two sources for the angular momentum, related to single-particle and collective motions, a much improved description of the experimental results can be obtained. In addition, new results on the structure of 208Fr, 211Ra and 216Ac are reported.

Podolyak, Zs.; Regan, P. H.; Walker, P. M.; Pearson, C. J.; Valiente-Dobon, J. J. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Gerl, J.; Hellstroem, M.; Becker, F.; Gorska, M.; Kelic, A.; Kopatch, Y.; Mandal, S.; Schmidt, K.-H.; Wollersheim, H. J.; Banu, A.; Geissel, H.; Grawe, H.; Kojouharov, I.; Lozeva, R.; Portillo, M. [CSI, Planckstrasse 1, D-64291 Darmstadt (Germany)] (and others)

2006-04-26

386

Laser cooling of externally produced Mg ions in a Penning trap for sympathetic cooling of highly charged ions  

NASA Astrophysics Data System (ADS)

We have performed laser cooling of Mg+ ions confined in a Penning trap. The externally produced ions were captured in flight, stored, and laser cooled. Laser-induced fluorescence was observed perpendicular to the cooling laser axis. Optical detection down to the single-ion level together with the electronic detection of the ion oscillations inside the Penning trap have been used to acquire information on the ion storage time, ion number, and ion temperature. Evidence for the formation of ion crystals has been observed. These investigations are an important prerequisite for the sympathetic cooling of simultaneously stored highly charged ions and the precision laser spectroscopy of forbidden transitions in these.

Andelkovic, Z.; Cazan, R.; Nörtershäuser, W.; Bharadia, S.; Segal, D. M.; Thompson, R. C.; Jöhren, R.; Vollbrecht, J.; Hannen, V.; Vogel, M.

2013-03-01

387

A 3rd Generation Advanced High-Strength Steel (AHSS) Produced by Dual Stabilization Heat Treatment (DSHT)  

NASA Astrophysics Data System (ADS)

A 3rd generation advanced high-strength steel containing, in wt pct, 0.3 C, 4.0 Mn, 1.5 Al, 2.1 Si, and 0.5 Cr has been produced using a dual stabilization heat treatment—a five stage thermal processing schedule compatible with continuous galvanized steel production. In excess of 30 vol pct retained austenite containing at least 0.80 wt pct C was achieved with this alloy, which had tensile strengths up to 1650 MPa and tensile elongations around 20 pct.

Qu, Hao; Michal, Gary M.; Heuer, Arthur H.

2013-10-01

388

K X-ray spectra of highly charged recoil ions produced by heavy-ion impact on oxygen  

Microsoft Academic Search

High-resolution oxygen K X-ray spectra of recoil ions produced by impact of 0.68 MeV amu-1 Ar and 1.4 MeV amu-1 C, Mg and Ar ions on oxygen-bearing molecular targets have been measured using a curved-crystal spectrometer. The spectra are dominated by H-like, He-like and Li-like transitions of the series np-1s, 1snp-1s2 and 1s2lnp-1s22l. A detailed analysis of the multiplet line

B. B. Bandong; R. L. Watson; J. Palinkas; C. Can

1988-01-01

389

Reproducibility of dobutamine digital stress echocardiography.  

PubMed

The aim of this study was to investigate the temporal variability and interobserver agreement of dobutamine digital stress echocardiography. We performed two dobutamine stress echocardiographic studies (dobutamine up to 40 micrograms/kg/min and atropine up to 1 mg) in 15 patients with previous myocardial infarction at a mean of 19 days apart. Two observers assessed the wall motion using a six-point score in a 16-segment model and calculated the wall motion score index at rest and at peak stress by using a quad screen display. Analysis of the wall motion was performed separately on the day after each dobutamine stress test (analysis A), and all images from the serial studies in the same patient were simultaneously retrieved and compared side-by-side in the same view (analysis B). The mean values of heart rate and blood pressure were comparable for each in the two studies except for the heart rate at rest. Regarding the presence and absence of positive findings of dobutamine stress echocardiography, interobserver agreement was 93% (70% to 99% with 95% confidence limits, kappa value 0.86) in the patients and 93% (70% to 99% with 95% confidence limits, kappa value 0.80) in the three major vascular regions with the use of analysis A. these values did not improve with the use of analysis B. The agreement of the temporal variability was 93% (70% to 99% with 95% confidence limits, kappa value 0.86) in the patients and 84% (71% to 92% with 95% confidence limits, kappa value 0.66) in the vascular regions with the use of analysis A. These values further improved with the use of analysis B. With the comparison of the wall motion score index, interobserver variability showed a correlation coefficient of 0.88 at rest and 0.90 at peak stress with analysis A and 0.78 and 0.82, respectively, with analysis B. Corresponding analysis of temporal variability showed correlation coefficients of 0.99 at rest and 0.99 at peak stress when both analysis were used. Although dobutamine digital stress echocardiography has good reproducibility and negligible interobserver variability, even if the digital quad screen format is used, it requires strict standardization of the reading criteria and the objective measurements of wall motion in the expansion of this test to the evaluation of the changes in left ventricular function during more than two serial studies in the same patient. PMID:9168356

Takeuchi, M; Sonoda, S; Miura, Y; Kuroiwa, A

1997-05-01

390

Reproducible and inexpensive probe preparation for oligonucleotide arrays.  

PubMed

We present a new protocol for the preparation of nucleic acids for microarray hybridization. DNA is fragmented quantitatively and reproducibly by using a hydroxyl radical-based reaction, which is initiated by hydrogen peroxide, iron(II)-EDTA and ascorbic acid. Following fragmentation, the nucleic acid fragments are densely biotinylated using a biotinylated psoralen analog plus UVA light and hybridized on microarrays. This non-enzymatic protocol circumvents several practical difficulties associated with DNA preparation for microarrays: the lack of reproducible fragmentation patterns associated with enzymatic methods; the large amount of labeled nucleic acids required by some array designs, which is often combined with a limited amount of starting material; and the high cost associated with currently used biotinylation methods. The method is applicable to any form of nucleic acid, but is particularly useful when applying double-stranded DNA on oligonucleotide arrays. Validation of this protocol is demonstrated by hybridizing PCR products with oligonucleotide-coated microspheres and PCR amplified cDNA with Affymetrix Cancer GeneChip microarrays. PMID:11433042

Zhang, Y; Price, B D; Tetradis, S; Chakrabarti, S; Maulik, G; Makrigiorgos, G M

2001-07-01

391

The accuracy and interobserver reproducibility of endometrial dating.  

PubMed

Although controversial, diagnosis of luteal phase defect (LPD) includes the morphological assessment of endometrial development. This study was conducted to determine if refresher training in the histological criteria could improve the accuracy and interobserver reproducibility of endometrial dating. Seventy-eight endometrial biopsies were dated by a reference panel of two pathologists and then reviewed twice by a study panel of four pathologists. In the first review, usual practice was applied. Prior to the second review, they studied a standard document of histological criteria. Samples were dated as proliferative, secretory (post-ovulatory day, POD), menstrual, and undatable. Accuracy levels based on the reference dating and agreement levels using kappa values were calculated per review and compared. The kappa for overall dating was 0.683 in the first review and 0.696 in the second. The respective first and second review kappa values were 0.736 and 0.771 for proliferative, and 0.794 and 0.764 for secretory. Amongst those dated as secretory in the first and second reviews, respectively, 31 and 28% were assigned the same POD by any two panellists, 68 and 63% were dated to within 1 day, and 77 and 71% were dated to within 2 days. Accuracy levels per panellist for overall dating were very high in both reviews but were low for individual PODs. Accuracy and interobserver reproducibility were unaffected by refresher training, suggesting the limits of histological dating have been reached. PMID:11523927

Duggan, M A; Brashert, P; Ostor, A; Scurry, J; Billson, V; Kneafsey, P; Difrancesco, L

2001-08-01

392

Reproducibility of the measurement of sweet taste preferences.  

PubMed

Developing interventions to prevent and treat obesity are medical and public health imperatives. Taste is a major determinant of food intake and reliable methods to measure taste preferences need to be established. This study aimed to establish the short-term reproducibility of sweet taste preference measurements using 5-level sucrose concentrations in healthy adult volunteers. We defined sweet taste preference as the geometric mean of the preferred sucrose concentration determined from two series of two-alternative, forced-choice staircase procedures administered 10min apart on a single day. We repeated the same procedures at a second visit 3-7days later. Twenty-six adults (13 men and 13 women, age 33.2±12.2years) completed the measurements. The median number of pairs presented for each series was three (25th and 75th percentiles: 3, 4). The intraclass correlation coefficients between the measurements was 0.82 (95% confidence interval [CI]: 0.63-0.92) within a few days. This study showed high short-term reproducibility of a simple, 5-level procedure for measuring sweet taste preferences. This method may be useful for assessing sweet taste preferences and the risks resulting from those preferences. PMID:22967817

Asao, Keiko; Luo, Wendy; Herman, William H

2012-09-08

393

Reproducing natural spider silks' copolymer behavior in synthetic silk mimics.  

PubMed

Dragline silk from orb-weaving spiders is a copolymer of two large proteins, major ampullate spidroin 1 (MaSp1) and 2 (MaSp2). The ratio of these proteins is known to have a large variation across different species of orb-weaving spiders. NMR results from gland material of two different species of spiders, N. clavipes and A. aurantia , indicates that MaSp1 proteins are more easily formed into ?-sheet nanostructures, while MaSp2 proteins form random coil and helical structures. To test if this behavior of natural silk proteins could be reproduced by recombinantly produced spider silk mimic protein, recombinant MaSp1/MaSp2 mixed fibers as well as chimeric silk fibers from MaSp1 and MaSp2 sequences in a single protein were produced based on the variable ratio and conserved motifs of MaSp1 and MaSp2 in native silk fiber. Mechanical properties, solid-state NMR, and XRD results of tested synthetic fibers indicate the differing roles of MaSp1 and MaSp2 in the fiber and verify the importance of postspin stretching treatment in helping the fiber to form the proper spatial structure. PMID:23110450

An, Bo; Jenkins, Janelle E; Sampath, Sujatha; Holland, Gregory P; Hinman, Mike; Yarger, Jeffery L; Lewis, Randolph

2012-11-08

394

Development of critical surface diagnostic based on the ion acoustic decay instability in laser produced high density plasma  

SciTech Connect

We have developed a large angle, UV collective Thomson scattering (CTS) diagnostic for high density, hot plasma relevant to laser fusion. The CTS measured the basic parameters of the plasma waves (frequency, wave number), or the spectral density function for selected wave vectors of plasma waves, which were excited by the IADI (ion acoustic parametric decay instability). It is a good diagnostic tool for a local electron temperature measurement. The electron temperature was estimated by measuring either ion acoustic wave or electron plasma wave in the laser intensity window of 1produced high density plasma.

Mizuno, K.; DeGroot, J.S.; Drake, R.P.; Seka, W.; Craxton, R.S.; Estabrook, K.G.

1994-12-31

395

Assessment of selenium bioavailability from naturally produced high-selenium soy foods in selenium-deficient rats.  

PubMed

We assessed the bioavailability of selenium (Se) from a protein isolate and tofu (bean curd) prepared from naturally produced high-Se soybeans. The Se concentrations of the soybeans, the protein isolate and tofu were 5.2±0.2, 11.4±0.1 and 7.4±0.1mg/kg, respectively. Male weanling Sprague-Dawley rats were depleted of Se by feeding them a 30% Torula yeast-based diet (4.1?g Se/kg) for 56 days, and then they were replenished with Se for an additional 50 days by feeding them the same diet containing 14, 24 or 30 ?g Se/kg from the protein isolate or 13, 23 or 31 ?g Se/kg from tofu, respectively. l-Selenomethionine (SeMet) was used as a reference. Selenium bioavailability was determined on the basis of the restoration of Se-dependent enzyme activities and tissue Se concentrations in Se-depleted rats, comparing those responses for the protein isolate and tofu to those for SeMet by using a slope-ratio method. Dietary supplementation with the protein isolate or tofu resulted in linear or log-linear, dose-dependent increases in glutathione peroxidase activities in blood and liver and in thioredoxin reductase activity in liver. Furthermore, supplementation with the protein isolate or tofu resulted in linear or log-linear, dose-dependent increases in the Se concentrations of plasma, liver, muscle and kidneys. These results indicated an overall bioavailability of approximately 101% for Se from the protein isolate and 94% from tofu, relative to SeMet. We conclude that Se from naturally produced high-Se soybeans is highly bioavailable in this model and that high-Se soybeans may be a good dietary source of Se. PMID:21093782

Yan, Lin; Reeves, Philip G; Johnson, LuAnn K

2010-06-03

396

Recovery of high purity zinc from filter ash produced during the thermal treatment of waste and inerting of residual materials.  

PubMed

The method described below recovers zinc, a valuable metal that is present in high concentrations in filter ash from the thermal treatment of waste, and returns the filter ash stripped of heavy metals to the combustion process in order to destroy organic substances. On an industrial scale, the heavy metals in the filter ash were mobilized by means of hydrochloric acid in the acidic fluids produced in the flue-gas scrubbing process without the addition of further chemicals. A pilot plant for implementing the selective reactive extraction (SRE) method on the ash extracts, using a highly selective complexant, was operated over a period of several months in order to obtain a concentrated, high-purity zinc salt solution (mono metal solution). A zinc depletion rate of 99.8% in the aqueous extract was achieved using mixer-settler units. The residual zinc concentration in the waste water was then < 2 mg L(-1). By stripping the loaded organic phase, a concentrated, high-purity mono metal solution with 190 g L(-1) zinc was obtained. Zinc metal with a purity > 99.99% is then separated by means of electrolysis. To destroy organic substances present in the filter ash, particularly dioxins and furans, the extracted filter ash cake was returned to the combustion process together with household waste. Plant operation, raw and pure gas parameters, and quality of the bottom ash produced were not impacted by such recirculation. The profitability of the overall process is attributable both to the recovery of valuable zinc metal and to the cost savings made in waste water treatment and in the disposal of the waste combustion residues because the remaining mixture of filter ash and bottom ash can be reused in a combined form. This method therefore supports the sustainable and economically viable reuse of filter ash. PMID:18229749

Schlumberger, Stefan; Schuster, Michael; Ringmann, Stefan; Koralewska, Ralf

2007-12-01

397

Africa Today: An Atlas of Reproducible Pages. 1990 Revised Edition. World Eagle's Today Series.  

ERIC Educational Resources Information Center

A collection of reproducible black and white maps, charts, and graphs for classroom use profiles Africa today. Individual country maps were originally produced by the United Nations, U.S. Department of State, and the U.S. Central Intelligence Agency. The material depicts the continent's (1) size, (2) population, (3) resources, (4) commodities, (5)…

World Eagle, Inc., Wellesley, MA.

398

Animal models of traumatic brain injury: Is there an optimal model to reproduce human brain injury in the laboratory?  

Microsoft Academic Search

Compared to other neurological diseases, the research surrounding traumatic brain injury (TBI) has a more recent history. The establishment and use of animal models of TBI remains vital to understand the pathophysiology of this highly complex disease. Such models share the ultimate goals of reproducing patterns of tissue damage observed in humans (thus rendering them clinically relevant), reproducible and highly

M. C. Morganti-Kossmann; E. Yan; N. Bye

2010-01-01

399

High titer production of tetracenomycins by heterologous expression of the pathway in a Streptomyces cinnamonensis industrial monensin producer strain.  

PubMed

Streptomyces cinnamonensis C730.1 and C730.7, are industrially mutagenized strains that produce moderate and high levels of the polyketide polyether antibiotic monensin A, respectively, in an oil-based fermentation medium. The possibility that these strains could be used for high titer production of a heterologous polyketide product was investigated by expression of the entire tetracenomycin (TCM) biosynthetic pathway using an integrative plasmid, pSET154. Expression in C730.1 led to stable production of approximately 0.44 g/l TCM C (the final biosynthetic product) and approximately 2.69 g/l TCM A2 (the penultimate biosynthetic product), and resulted in a 40% decrease in monensin production. Expression in the C730.7 led to higher levels of TCMs, approximately 0.6 g/l TCM C and approximately 4.35 g/l TCM A2, without any detectable decrease in the higher titer monensin production. Abrogation of monensin production in this strain through deletion of the corresponding biosynthetic genes did not lead to higher levels of TCM products. In the case of the C730.7 host, 85% of the TCM C and virtually all of the TCM A2 were intracellular, suggesting feedback inhibition leads to the accumulation of the final pathway intermediate. These observations contrast those made for the native producer Streptomyces glaucescens where the predominant product is TCM C and TCM titers are significantly lower levels (approximately 0.3 g/l), and demonstrate the potential utility of S. cinnamonensis strains as heterologous hosts for high level expression of a variety of polyketide synthase derived products. PMID:19595787

Li, Chaoxuan; Hazzard, Chris; Florova, Galina; Reynolds, Kevin A

2009-07-10

400

A simple, reproducible substrate for studying biofilms in aquatic environments.  

PubMed

In this paper we present a simple in expensive substrate for studying biofilms. Bioballs are robust plastic spheres with high surface area to volume ratios (ca 130:1) used in home aquarium filters. Their properties make them ideal substrates for use in studies of aquatic biofilms. As examples, in this paper we describe the growth and enzyme activities of biofilms grown on these substrates and explore the interaction between DOC concentration and biofilm biomass. Biofilm growth and activity on the bioballs was very reproducible. For example maximum biofilm growth following approximately 3 months inundation was estimated to be 40 (+/- 3.6) mg protein and 120 (+/- 11) microg chlorophyll a per bioball. PMID:12868526

Baldwin, D S; Rees, G N; Edwards, M; Robertson, A I

2003-06-01

401

Physiologic and metabolic characterization of a new marine isolate (BM39) of Pantoea sp. producing high levels of exopolysaccharide  

PubMed Central

Background Marine environments are the widest fonts of biodiversity representing a resource of both unexploited or unknown microorganisms and new substances having potential applications. Among microbial products, exopolysaccharides (EPS) have many physiological functions and practical applications. Since EPS production by many bacteria is too scarce for practical use and only few species are known for their high levels of production, the search of new high EPS producers is of paramount importance. Many marine bacteria, that produce EPS to cope with strong environmental stress, could be potentially exploited at the industrial level. Results A novel bacterium, strain BM39, previously isolated from sediments collected in the Tyrrhenian Sea, was selected for its production of very high levels of EPS. BM39 was affiliated to Pantoea sp. (Enterobacteriaceae) by 16S rRNA gene sequencing and biochemical tests. According to the phylogenetic tree, this strain, being quite far from the closest known Pantoea species (96% identity with P. agglomerans and P. ananatis) could belong to a new species. EPS production was fast (maximum of ca. 21 g/L in 24 h on glucose medium) and mainly obtained during the exponential growth. Preliminary characterization, carried out by thin layer and gel filtration chromatography, showed that the EPS, being a glucose homopolymer with MW of ca. 830 kDa, appeared to be different from those of other bacteria of same genus. The bacterium showed a typical slightly halophilic behavior growing optimally at NaCl 40 ‰ (growing range 0-100 ‰). Flow cytometry studies indicated that good cell survival was maintained for 24 h at 120 ‰. Survival decreased dramatically with the increase of salinity being only 1 h at 280 ‰. The biochemical characterization, carried out with the Biolog system, showed that MB39 had a rather limited metabolic capacity. Its ability, rather lower than that of P. agglomerans, was almost only confined to the metabolization of simple sugars and their derivatives. Few alcohols, organic acids and nitrogen compounds were partially used too. Conclusions Strain BM39, probably belonging to a new species, due to its remarkable EPS production, comparable to those of known industrial bacterial producers, could be suggested as a new microorganism for industrial applications.

2013-01-01

402

Reproducibility of a Triaxial Seismic Accelerometer (DynaPort)  

Microsoft Academic Search

VAN HEES, V. T., S. M. SLOOTMAKER, G. DE GROOT, W. VAN MECHELEN, and R. C. VAN LUMMEL. Reproducibility of a Triaxial Seismic Accelerometer (DynaPort). Med. Sci. Sports Exerc., Vol. 41, No. 4, pp. 810-817, 2009. Purpose: To examine the reproducibility of a triaxial seismic accelerometer under controlled conditions and real-life conditions. Methods: Instrumental reproducibility was examined using a shaker

VINCENT T. VAN HEES; SANDER M. SLOOTMAKER; GERT DE GROOT; WILLEM VAN MECHELEN; ROB C. VAN LUMMEL

2009-01-01

403

Microbial community structure analysis of produced water from a high-temperature North Sea oil-field.  

PubMed

Molecular and culture-based methods were used to investigate the microbial diversity in produced water obtained from the high-temperature Troll oil formation in the North Sea. 16S rRNA gene libraries were generated from total community DNA, using universal archaeal or bacterial oligonucleotide primer sets. Sequence analysis of 88 clones in the bacterial library indicated that they originated from members of Firmicutes (48 sequences), Bacteroidetes (17 sequences), delta-Proteobacteria (15 sequences), Spirochaetes (5 sequences), Thermotogales (2 sequences) and gamma-Proteobacteria (1 sequence). Twenty-two sequences in the archaeal library were close relatives to members of the genera Methanococcus (18 sequences), Methanolobus (3 sequences) and Thermococcus (1 sequence). Most of the bacterial sequences shared less than 95% identity with their closest match in GenBank, indicating that the produced water harbours a unique community of novel bacterial species or genera. Members of the thermophilic genera Thermosipho, Thermotoga, Anaerophaga and Thermovirga were isolated. The Troll formations are not injected with sea water. Thus, dramatic changes of the in situ conditions have been avoided, and a common source of continuous contamination from injection water can be excluded. However, the majority of the organisms detected in the gene libraries were most closely related to cultivated organisms with optimum temperatures for growth well below the in situ reservoir temperature (70 degrees C), indicating that produced water from the Troll platform harbours a substantial amount of non-indigenous organisms. This was confirmed by the isolation of a number of mesophilic and moderately thermophilic organisms that were unable to grow at reservoir temperature. PMID:17588160

Dahle, Håkon; Garshol, Frøydis; Madsen, Marit; Birkeland, Nils-Kåre

2007-06-22

404

Compact experimental apparatus for producing high-repetition-rate 87Rb Bose-Einstein condensation on an atom chip  

NASA Astrophysics Data System (ADS)

We construct a compact experimental apparatus for producing high-repetition-rate ultra cold 87Rb atom based on an external atom chip. Initially, we produce an atomic flux from a 2D+ MOT (magneto-optical trap) in a nearly isolated 2D+ MOT chamber and improve the flux by adjusting the cooling beam detuning of the 2D+ MOT. The flux is trapped in the 3D MOT for 1.2 s and is further cooled by performing compressing the MOT for 20 ms and using polarization gradient cooling for 6.2 ms. After optical pumping into the 5 S F = 2 ( m F = 2) ground state, we transport atoms toward the chip surface by performing external Z coil trapping. At 1 mm below the chip surface, the external Z coil trap is completely switched to an atom chip trap by using a Z wire and a dimple wire on the chip with external bias fields. The transport and the switching take totally 520 ms. The number of atoms trapped on the atom chip is measured to be about 2 × 107. After the atoms has been compressed for 100 ms to increase trap frequencies, we perform RF evaporative cooling in the RF frequency range from 32 MHz to 6.82 MHz for 2.4 seconds. The final number of atoms in the atomic cloud after RF cooling is 1.2 × 105 atoms, and we are able to observe some Bose-Einstein condensation. The repetition rate for producing the condensation is 0.234 Hz. In this paper, we describe our experimental apparatus and processes.

Yu, Hoon; Kim, Seung Jin; Moon, Ye Lin; Kim, Jung Bog; Lee, Jin Seung

2013-08-01

405

High-resolution imaging spectrometer for recording absolutely calibrated far ultraviolet spectra from laser-produced plasmas  

SciTech Connect

An imaging spectrometer was designed and fabricated for recording far ultraviolet spectra from laser-produced plasmas with wavelengths as short as 155 nm. The spectrometer implements a Cassegrain telescope and two gratings in a tandem Wadsworth optical configuration that provides diffraction limited resolution. Spectral images were recorded from plasmas produced by the irradiation of various target materials by intense KrF laser radiation with 248 nm wavelength. Two pairs of high-resolution gratings can be selected for the coverage of two wavebands, one grating pair with 1800 grooves/mm and covering approximately 155-175 nm and another grating pair with 1200 grooves/mm covering 230-260 nm. The latter waveband includes the 248 nm KrF laser wavelength, and the former waveband includes the wavelength of the two-plasmon decay instability at (2/3) the KrF laser wavelength (165 nm). The detection media consist of a complementary metal oxide semiconductor imager, photostimulable phosphor image plates, and a linear array of 1 mm{sup 2} square silicon photodiodes with 0.4 ns rise time. The telescope mirrors, spectrometer gratings, and 1 mm{sup 2} photodiode were calibrated using synchrotron radiation, and this enables the measurement of the absolute emission from the laser-produced plasmas with temporal, spatial, and spectral resolutions. The spectrometer is capable of measuring absolute spectral emissions at 165 nm wavelength as small as 5x10{sup -7} J/nm from a plasma source area of 0.37 mm{sup 2} and with 0.4 ns time resolution.

Brown, Charles M.; Seely, John F. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Feldman, Uri [ARTEP Inc., Ellicott City, Maryland 21042 (United States); Holland, Glenn E. [SFA Inc., 2200 Defense Highway, Suite 405, Crofton, Maryland 21114 (United States); Weaver, James L.; Obenschain, Steven P. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Kjornrattanawanich, Benjawan [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973, USA and Universities Space Research Associates, Columbia, Maryland 21044 (United States); Fielding, Drew [Commonwealth Technologies Inc., 5775 Barclay Drive, Alexandria, Virginia 22315 (United States)

2008-10-15

406

A novel strategy to produce highly stable and transparent aqueous 'nanosolutions' of water-insoluble drug molecules.  

PubMed

A surprisingly large proportion of new drug candidates emerging from drug discovery programmes are water-insoluble and, as a result, have poor oral bioavailability. To overcome insolubility, the drug particles are usually dispersed in a medium during product formation, but large particles that are formed may affect product performance and safety. Many techniques have been used to produce nanodispersions-dispersions with nanometre-scale dimensions-that have properties similar to solutions. However, making nanodispersions requires complex processing, and it is difficult to achieve stability over long periods. In this paper, we report a generic method for preparing drug nanoparticles with a combination of antisolvent precipitation in the presence of water-soluble matrices and spray-drying. The spray-dried powder composites (solid dispersion) are microspherical, highly stable and thus form transparent nanodispersions or so-called 'nanosolutions' of water-insoluble drug when simply added to water. Aqueous nanodispersions of silybin (a kind of water-insoluble drug for liver protection) with an average size of 25 nm produced with this approach display a 10 times faster dissolution rate than that of raw drug. This has great potential to offer a novel solution for innovative drugs of the future. PMID:21705830

Wang, Jie-Xin; Zhang, Zhi-Bing; Le, Yuan; Zhao, Hong; Chen, Jian-Feng

2011-06-27

407

A novel strategy to produce highly stable and transparent aqueous 'nanosolutions' of water-insoluble drug molecules  

NASA Astrophysics Data System (ADS)

A surprisingly large proportion of new drug candidates emerging from drug discovery programmes are water-insoluble and, as a result, have poor oral bioavailability. To overcome insolubility, the drug particles are usually dispersed in a medium during product formation, but large particles that are formed may affect product performance and safety. Many techniques have been used to produce nanodispersions—dispersions with nanometre-scale dimensions—that have properties similar to solutions. However, making nanodispersions requires complex processing, and it is difficult to achieve stability over long periods. In this paper, we report a generic method for preparing drug nanoparticles with a combination of antisolvent precipitation in the presence of water-soluble matrices and spray-drying. The spray-dried powder composites (solid dispersion) are microspherical, highly stable and thus form transparent nanodispersions or so-called 'nanosolutions' of water-insoluble drug when simply added to water. Aqueous nanodispersions of silybin (a kind of water-insoluble drug for liver protection) with an average size of 25 nm produced with this approach display a 10 times faster dissolution rate than that of raw drug. This has great potential to offer a novel solution for innovative drugs of the future.

Wang, Jie-Xin; Zhang, Zhi-Bing; Le, Yuan; Zhao, Hong; Chen, Jian-Feng

2011-07-01

408

Effects of OLRs and HRTs on hydrogen production from high salinity substrate by halophilic hydrogen producing bacterium (HHPB).  

PubMed

The effects of hydraulic retention time (HRT) and organic loading rate (OLR) on hydrogen production were investigated with glucose medium containing 2% NaCl. Halophilic hydrogen producing bacterium (HHPB) Clostridium bifermentans 3AT-ma, which can survive under high salt conditions, was used. Sponge media were used as 20% of working volume. The OLR and HRT were varied in 10-60 g-glucose/L-reactor/day and 24-6h. With OLR of 20 g-glucose/L/day, shorter HRT resulted in higher hydrogen producing rate and yield. When the OLR was increased from 20 to 60 g-glucose/L-reactor/day at HRT 6h, the hydrogen production rate increased, while the hydrogen production yield decreased due to the increase and accumulation of volatile fatty acids. Biohydrogen production was possible from the salinity substrate using HHPB, and the maximum hydrogen production yield was 1.1 mol-H?/mol-glucose with optimal conditions of OLR of 20 g-glucose/L/day and HRT of 12h. PMID:23305894

Zhang, Shan; Lee, Yunhee; Kim, Tae-Hyeong; Hwang, Sun-Jin

2012-12-17

409

Reproducibility of a life-cycle toxicity test with Daphnia magna  

SciTech Connect

Standardized chronic life-cycle toxicity testing procedures for aquatic species are described. The reproducibility of chronic toxicity and points using the static-renewal method with Daphnia magna are investigated. The objectives were to determine if the lowest rejected concentrations tested (LRCTs) obtained for six different toxicity criteria in static-renewal tests with acridine were reproducible over time and to determine the relative sensitivity and variability of the toxicity criteria. Two of the six toxicity criteria, numbers of young per brood and the young produced per female, were found to be reliable and sensitive for estimating the LRCT for acridine to D. magna. (RJC)

Parkhurst, B.R.; Forte, J.L.; Wright, G.P.

1981-01-01

410

Reproducibility of gemifloxacin and comparison fluoroquinolone MIC results using Sensititre commercial dry-form panels.  

PubMed

This study examined the ability of commercial dry-form broth microdilution panels (Sensititre, TREK Diagnostics, Cleveland, OH) to produce accurate minimum inhibitory concentration (MIC) results for gemifloxacin, a new fluoroquinolone. Reproducibility for gemifloxacin was 100.0% for on-scale values within +/-1 log2 dilution for same- and between-day comparisons. Newer comparator fluoroquinolones (sparfloxacin, sitafloxacin, and moxifloxacin) also showed excellent reproducibility (100.0%) for on-scale results analyzed at +/-1 log2 dilution for same- and between-day comparisons. Newer and investigational fluoroquinolone agents, including gemifloxacin, can be tested with confidence using these dry-form MIC panels. PMID:15766610

Ross, James E; Sader, Helio S; Fritsche, Thomas R; Jones, Ronald N

2005-03-01

411

Accurate, reproducible measurement of blood pressure.  

PubMed Central

The diagnosis of mild hypertension and the treatment of hypertension require accurate measurement of blood pressure. Blood pressure readings are altered by various factors that influence the patient, the techniques used and the accuracy of the sphygmomanometer. The variability of readings can be reduced if informed patients prepare in advance by emptying their bladder and bowel, by avoiding over-the-counter vasoactive drugs the day of measurement and by avoiding exposure to cold, caffeine consumption, smoking and physical exertion within half an hour before measurement. The use of standardized techniques to measure blood pressure will help to avoid large systematic errors. Poor technique can account for differences in readings of more than 15 mm Hg and ultimately misdiagnosis. Most of the recommended procedures are simple and, when routinely incorporated into clinical practice, require little additional time. The equipment must be appropriate and in good condition. Physicians should have a suitable selection of cuff sizes readily available; the use of the correct cuff size is essential to minimize systematic errors in blood pressure measurement. Semiannual calibration of aneroid sphygmomanometers and annual inspection of mercury sphygmomanometers and blood pressure cuffs are recommended. We review the methods recommended for measuring blood pressure and discuss the factors known to produce large differences in blood pressure readings.

Campbell, N R; Chockalingam, A; Fodor, J G; McKay, D W

1990-01-01

412

High performance liquid chromatographic assay of disaccharides and oligosaccharides produced by the digestion of glycosaminoglycans with chondroitin sulphate lyases.  

PubMed

In high performance liquid chromatographic procedures hitherto described, SiO2, NH2 and RP columns have been used for the analysis of disaccharides produced by the digestion of glycosaminoglycans with the chondroitin sulphate lyases AC and ABC. The use of a potent anion exchanger offers the following advantages over these columns: superior separation characteristics for non-sulphated disaccharides, and improved column performance, coupled with more stable analytical conditions. Elution with dilute saline solutions permits separation of the two non-sulphated disaccharides from chondroitin and hyaluronate. The sequential application of chondroitinase AC and ABC permits the determination of hyaluronate, the chondroitin sulphate isomers and the dermatan sulphate isomers by high performance liquid chromatographic separation of the products of enzymatic hydrolysis. In a previously described method, hyaluronate lyase was used for the determination of hyaluronate. It has been found, however, that omission of the hyaluronate lyase step results in superior accuracy in the high performance liquid chromatographic separation of the non-sulphated disaccharides. The enzymatic analysis of human articular cartilage glycosaminoglycans has repeatedly yielded a fraction which is not digestable by chondroitinase AC, but is completely digestable by chondroitinase ABC. More extensive characterization has disclosed that this fraction differs structurally from chondroitin sulphate. Enzymatic characterization indicates that it should presumably be assigned to dermatan sulphate. PMID:3989479

Gurr, E; Pallasch, G; Tunn, S; Tamm, C; Delbrück, A

1985-02-01

413

High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas.  

PubMed

A large radius, R=44.3 m, high resolution grating spectrometer (HRGS) with 2400 lines/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 A wavelength range. The instrument can be run with a 10-20 microm wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 A, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (full width at half maximum), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies. PMID:19044476

Dunn, J; Magee, E W; Shepherd, R; Chen, H; Hansen, S B; Moon, S J; Brown, G V; Gu, M-F; Beiersdorfer, P; Purvis, M A

2008-10-01

414

High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas  

SciTech Connect

A large radius, R = 44.3 m, High Resolution Grating Spectrometer (HRGS) with 2400 line/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 {angstrom} wavelength range. The instrument can be run with a 10-20 {micro}m wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 {angstrom}, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (FWHM), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies.

Dunn, J; Magee, E W; Shepherd, R; Chen, H; Hansen, S B; Moon, S J; Brown, G V; Gu, M; Beiersdorfer, P; Purvis, M A

2008-05-21

415

Local bioprospecting for high-lipid producing microalgal strains to be grown on concentrated municipal wastewater for biofuel production.  

PubMed

Mass cultivation of microalgae for biofuel production depends heavily on the performance of the microalgae strains used. In this study, 60 algae-like microorganisms collected from different sampling sites in Minnesota were examined using multi-step screening and acclimation procedures to select high-lipid producing facultative heterotrophic microalgae strains capable of growing on concentrated municipal wastewater (CMW) for simultaneous energy crop production and wastewater treatment. Twenty-seven facultative heterotrophic microalgae strains were found, among which 17 strains were proved to be tolerant to CMW. These 17 top-performing strains were identified through morphological observation and DNA sequencing as Chlorella sp., Heynigia sp., Hindakia sp., Micractinium sp., and Scenedesmus sp. Five strains were chosen for other studies because of their ability to adapt to CMW, high growth rates (0.455-0.498 d(-1)) and higher lipid productivities (74.5-77.8 mg L(-1)d(-1)). These strains are considered highly promising compared with other strains reported in the literature. PMID:21546246

Zhou, Wenguang; Li, Yecong; Min, Min; Hu, Bing; Chen, Paul; Ruan, Roger

2011-04-20

416

Reproducibility of intracardiac and transpulmonary biomarkers in the evaluation of pulmonary hypertension  

PubMed Central

Intracardiac and transpulmonary levels of natriuretic peptides (NPs) and cyclic guanosine monophosphate (cGMP) provide insight into the pathophysiology of pulmonary hypertension (PH) secondary to left-heart failure but have not been evaluated in established or suspected pulmonary arterial hypertension (PAH). Demonstrating adequate reproducibility of these markers is an important precursor to further study. We hypothesized that the reproducibility of intracardiac and transpulmonary NPs and cGMP is similar to the reproducibility of these markers sampled from the peripheral venous circulation. In outpatients undergoing right-heart catheterization for PH, blood samples were obtained from a peripheral venous site, superior vena cava, inferior vena cava, coronary sinus, pulmonary artery, and pulmonary capillary wedge position. At each site, a repeat sample was collected approximately 60 seconds after the initial measurement. Reproducibility was assessed using the slope of the regression line between initial and follow-up levels. We enrolled 10 patients: Six had PAH, two had pulmonary venous hypertension, and two had normal pulmonary pressure. At all sites, the slopes of the regression lines for BNP were close to identity. BNP was generally more reproducible than NT-pro-BNP. For the NPs and cGMP, reproducibility at intracardiac and transpulmonary sites was similar to the peripheral venous site. Reproducibility of NPs was not influenced by PH severity, access site, or time between measurements. The two patients with the highest transpulmonary pressure gradients had high transpulmonary BNP uptake, but their transpulmonary cGMP gradients were negative. In patients evaluated for PH, reproducibility of NPs and cGMP at intracardiac and transpulmonary sites is high and is comparable to that of peripheral venous measurements.

Monahan, Ken; Scott, Theresa A.; Su, Yan Ru; Lenneman, Carrie G.; Zhao, David X.; Robbins, Ivan M.; Hemnes, Anna R.

2013-01-01

417

Combining ion figuring and SPSI testing to produce a high-quality aspheric 18-inch-diameter f/2 mirror  

NASA Astrophysics Data System (ADS)

Ion figuring is an efficient and deterministic process for fabricating high quality optical surfaces. The simultaneous phase shifting interferometer is a helium-neon laser-based Twyman-Green system capable of data acquisition at shutter speeds of up to 1/10,000th of a second, which eliminates vibration effects. Ion figuring and simultaneous phase shifting interferometry were successfully combined to produce an aspheric, 18 inch diameter, f/2, ULE mirror of exceptional surface figure quality. Through iterative cycles of SPSI testing and ion figuring, the mirror surface was processed to a final figure quality of 0.007 (lambda) rms (95% of data

Carbone, Frank A.; Markle, David A.

1995-09-01

418

Thermal stability and microhardness of Cu-10vol.%Al2O3nanocomposite produced by high energy mechanical milling  

NASA Astrophysics Data System (ADS)

Cu-10vol.%Al2O3 nanocomposite powders were produced using two high energy milling routes and heat treated at 150, 300, 400 and 500°C for 1 hour, respectively, to determine the thermal stability of the microstructure and the micohardness change of the materials as a function of the annealing temperature. Annealing of the as-milled powders at 150°C caused recovery and recrystallisation that leads to significant decrease in dislocation density and slight decrease of microhardness. Increasing the annealing temperature to 400°C causes slight coarsening of the Cu grains and corresponding slight decrease of microhardness. Further increasing the annealing temperature to 500°C causes significant coarsening of the Cu grains and cause significant decrease in microhardness. The effects of different factors on the thermal stability and micohardness change of the Cu-Al2O3 are discussed.

Mukhtar, A.; Zhang, D. L.; Kong, C.; Munroe, P.

2009-01-01

419

High spin studies of neutron-rich nuclei produced in the spontaneous fission process of californium-252  

NASA Astrophysics Data System (ADS)

From an experiment with GAMMMASPHERE and a 252Cf spontaneous fission source, high spin studies of several neutron-rich nuclei have been carried out. In the mass region A ~ 150, a new negative-parity band in 154Nd and new negative-parity levels in 152Nd were identified and the yrast bands were extended to 18+ in 154Nd and 20+ 152Nd in a triple gamma coincidence study. These new negative-parity bands are consistent with octupole vibrational mode rather than the stable octupole deformation seen in Ba and Ce nuclei. There is a constant difference as a function of spin between the J1 values for the negative-parity band in 152Nd and J1 for the similar negative-parity band in 154Nd, however, their J2 values are essentially identical above the 4 + state. These bands indicate a new kind of identical bands associated with an octupole vibrational mode. In mass region A ~ 110, we have observed new bands in 113,115,117,118 Pd up to moderately high spin. The newly identified negative-parity yrast band energy level systematics built on the / isomeric states fit smoothly with the known systematic for other Pd isotopes, and show a minimum excitation energy at N = 68 related to a mid-shell closure. These new negative- parity yrast bands indicate a first band crossing at ¢? ~ 0.45 MeV, nearly identical to those seen in 109,111Pd, but significantly higher than those in the positive yrast parity bands in 113,115Pd and in the even-even Pd isotopes. We have interpreted the new negative-parity yrast bands as having band crossings from the alignment of a nh/ pair, and this suggests that 113,115,117Pd maintain a prolate shape. Additionally, we have observed two new bands in 113,115 Pd, which are tentatively assigned positive parity with band crossings about 0.25 and 0.32 MeV. These lower frequencies are consistent with a nh/ pair alignment. In the neutron-rich 118Pd, the first band crossing at a frequency of ¢? ~ 0.29 MeV was observed in its yrast band. This band crossing frequency is substantially lower than the first band crossing frequency of ¢? ~ 0.45 MeV observed the yrast bands in the lighter odd mass Pd isotopes and the crossing at ¢? = 0.35 in the yrast bands in 112,114,116Pd. This lower crossing frequency is well reproduced by the quasi- neutron Routhian calculation by assuming that the neutron-pairing gap is reduced in 118Pd. The calculation show a two nh/ band crossing at ¢? ~ 0.3 in agreement with the experimental value. A reduction in neutron pairing is responsible in Cranking model for lowering the crossing frequency. This band crossing in the new yrast cascade in 118Pd as well as those in 112,114,116Pd are interpreted based on a two h/ neutron configuration. Our result indicates 118 Pd still maintains a prolate shape. It's found that the crossing frequency in 118Pd is considerably lower and weaker than for the other even Pd isotopes. In the even-even 88,90,92Kr, all yrast bands were studied and extended to 8+, 10+, 12+, respectively. Quasi-gamma bands in 90,92Kr, and possibly one in 88Kr were identified. These data provide useful information about the interplay of collective and independent particle excitations in these three nuclei. Additionally, the coexisting of vibrational motion near the ground state and rotational collective motion at intermediate spins is observed in neutron-rich 90Kr.

Zhang, Xueqian

2001-08-01

420

Relationships between milk production, ovarian function and fertility in high-producing dairy herds in north-eastern Spain.  

PubMed

In the dairy industry worldwide, reproductive disorders are a major cause of economic losses and a challenge to scientists and technicians. In recent decades, declining fertility and increasing milk production have been widely reported in dairy cattle. In this article, the relationships between milk production, ovarian disorders and fertility in high-producing dairy herds are briefly described. We carried out a retrospective study of 23 204 lactations included in a reproductive control programme in north-eastern Spain, a geographical area experiencing both warm and cool conditions. The data were collected between 1991 and 2007 and refer to cows first inseminated or examined 45-80 days postpartum in five well-managed, commercial, Holstein-Friesian high-producing dairy herds. Ovarian disorders were classified as ovarian inactivity or hypofunction, cystic ovarian disease, sub-oestrus or silent ovulation and sub-luteal function. Ovarian hypofunction and milk production increased throughout the study period and there was a decrease in the pregnancy rate to first artificial insemination (AI). Cows suffering ovarian hypofunction were efficiently treated using combined progestagen-prostaglandin treatments. The incidence of ovarian cysts showed little variation with time. Treatment of this syndrome may include different GnRH-based treatments or manual rupture. During the last 5 years, sub-oestrus was the predominant dysfunction (42.1%) compared with the cystic (6.3%) and ovarian hypofunction (12%) forms. Response of sub-oestrous cows to treatment with luteolitic agents was usually higher than 60%. Ovarian function and fertility were dramatically impaired during the warm period. However, during the later years of the study, the inclusion of fans and water sprinklers for the warm season appeared to overcome the seasonal effect on fertility. PMID:18803755

Yániz, J; López-Gatius, F; Bech-Sàbat, G; García-Ispierto, I; Serrano, B; Santolaria, P

2008-10-01

421

Chemostat Enrichments of Human Feces with Resistant Starch Are Selective for Adherent Butyrate-Producing Clostridia at High Dilution Rates  

PubMed Central

Resistant starch (RS) enrichments were made using chemostats inoculated with human feces from two individuals at two dilution rates (D = 0.03 h?1 and D = 0.30 h?1) to select for slow- and fast-growing amylolytic communities. The fermentations were studied by analysis of short-chain fatty acids, amylase and ?-glucosidase activities, and viable counts of the predominant culturable populations and the use of 16S rRNA-targeted oligonucleotide probes. Considerable butyrate was produced at D = 0.30 h?1, which corresponded with reduced branched-chain fatty acid formation. At both dilution rates, high levels of extracellular amylase activity were produced,