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1

(re)producing Good Science Students: Girls' Participation in High School Physics  

NASA Astrophysics Data System (ADS)

In this ethnographic study, the author describes the meanings of science and science student in a physics classroom in an upper-middle-class high school and the ways girls participated within these meanings. The classroom practices reproduced prototypical meanings of science (as authoritative) and science student (as "dutiful"). The results highlight girls' embrace of prototypical school science. Yet at the end of the school year, the girls did not consider themselves "science people," nor did they want to pursue physics further. The author's interpretation of these results takes seriously girls' agency in producing the meaning of the physics class (as a way to polish one's transcript) and draws attention to the promoted identities (prototypical good student identities) in the classroom. The author argues that students' agency in resisting or accepting the practices, identities, and knowledge of school science is worth understanding for the improvement of science education.

Carlone, Heidi B.

2

The doubly labeled water method produces highly reproducible longitudinal results in nutrition studies.  

PubMed

The doubly labeled water (DLW) method is considered the reference method for the measurement of energy expenditure under free-living conditions. However, the reproducibility of the DLW method in longitudinal studies is not well documented. This study was designed to evaluate the longitudinal reproducibility of the DLW method using 2 protocols developed and implemented in a multicenter clinical trial-the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE). To document the longitudinal reproducibility of the DLW method, 2 protocols, 1 based on repeated analysis of dose dilutions over the course of the clinical trial (dose-dilution protocol) and 1 based on repeated but blinded analysis of randomly selected DLW studies (test-retest protocol), were carried out. The dose-dilution protocol showed that the theoretical fractional turnover rates for (2)H and (18)O and the difference between the 2 fractional turnover rates were reproducible to within 1% and 5%, respectively, over 4.5 y. The Bland-Altman pair-wise comparisons of the results generated from 50 test-retest DLW studies showed that the fractional turnover rates and isotope dilution spaces for (2)H and (18)O, and total energy expenditure, were highly reproducible over 2.4 y. Our results show that the DLW method is reproducible in longitudinal studies and confirm the validity of this method to measure energy expenditure, define energy intake prescriptions, and monitor adherence and body composition changes over the period of 2.5-4.4 y. The 2 protocols can be adopted by other laboratories to document the longitudinal reproducibility of their measurements to ensure the long-term outcomes of interest are meaningful biologically. This trial was registered at clinicaltrials.gov as NCT00427193. PMID:24523488

Wong, William W; Roberts, Susan B; Racette, Susan B; Das, Sai Krupa; Redman, Leanne M; Rochon, James; Bhapkar, Manjushri V; Clarke, Lucinda L; Kraus, William E

2014-05-01

3

Highly reliable field electron emitters produced from reproducible damage-free carbon nanotube composite pastes with optimal inorganic fillers  

NASA Astrophysics Data System (ADS)

Highly reliable field electron emitters were developed using a formulation for reproducible damage-free carbon nanotube (CNT) composite pastes with optimal inorganic fillers and a ball-milling method. We carefully controlled the ball-milling sequence and time to avoid any damage to the CNTs, which incorporated fillers that were fully dispersed as paste constituents. The field electron emitters fabricated by printing the CNT pastes were found to exhibit almost perfect adhesion of the CNT emitters to the cathode, along with good uniformity and reproducibility. A high field enhancement factor of around 10 000 was achieved from the CNT field emitters developed. By selecting nano-sized metal alloys and oxides and using the same formulation sequence, we also developed reliable field emitters that could survive high-temperature post processing. These field emitters had high durability to post vacuum annealing at 950 °C, guaranteeing survival of the brazing process used in the sealing of field emission x-ray tubes. We evaluated the field emitters in a triode configuration in the harsh environment of a tiny vacuum-sealed vessel and observed very reliable operation for 30 h at a high current density of 350 mA cm-2. The CNT pastes and related field emitters that were developed could be usefully applied in reliable field emission devices.

Kim, Jae-Woo; Jeong, Jin-Woo; Kang, Jun-Tae; Choi, Sungyoul; Ahn, Seungjoon; Song, Yoon-Ho

2014-02-01

4

Highly reliable field electron emitters produced from reproducible damage-free carbon nanotube composite pastes with optimal inorganic fillers.  

PubMed

Highly reliable field electron emitters were developed using a formulation for reproducible damage-free carbon nanotube (CNT) composite pastes with optimal inorganic fillers and a ball-milling method. We carefully controlled the ball-milling sequence and time to avoid any damage to the CNTs, which incorporated fillers that were fully dispersed as paste constituents. The field electron emitters fabricated by printing the CNT pastes were found to exhibit almost perfect adhesion of the CNT emitters to the cathode, along with good uniformity and reproducibility. A high field enhancement factor of around 10,000 was achieved from the CNT field emitters developed. By selecting nano-sized metal alloys and oxides and using the same formulation sequence, we also developed reliable field emitters that could survive high-temperature post processing. These field emitters had high durability to post vacuum annealing at 950 °C, guaranteeing survival of the brazing process used in the sealing of field emission x-ray tubes. We evaluated the field emitters in a triode configuration in the harsh environment of a tiny vacuum-sealed vessel and observed very reliable operation for 30 h at a high current density of 350 mA cm(-2). The CNT pastes and related field emitters that were developed could be usefully applied in reliable field emission devices. PMID:24434798

Kim, Jae-Woo; Jeong, Jin-Woo; Kang, Jun-Tae; Choi, Sungyoul; Ahn, Seungjoon; Song, Yoon-Ho

2014-02-14

5

Reproducible High Yields of Recombinant Adeno-Associated Virus Produced Using Invertebrate Cells in 0.02- to 200-Liter Cultures  

PubMed Central

Abstract The large amounts of recombinant adeno-associated virus (rAAV) vector needed for clinical trials and eventual commercialization require robust, economical, reproducible, and scalable production processes compatible with current good manufacturing practice. rAAV produced using baculovirus and insect cells satisfies these conditions; however, recovering rAAV particles from 200-liter bioreactors is more complicated than bench-scale vector preparations. Using a variety of processing media, we developed a reliable and routine downstream procedure for rAAV production that is scalable from 0.02- to 200-liter cultures. To facilitate the upstream process, we adapted the titerless infected-cell preservation and scale-up process for rAAV production. Single-use aliquots of cryopreserved baculovirus-infected insect cells (BIIC) are thawed and added to the suspension culture to achieve the desired ratio of BIIC to rAAV-producer cells. By using conditions established with small-scale cultures, rAAV was produced in larger volume cultures. Strikingly consistent rAAV yields were attained in cultures ranging from 10 liters to 200 liters. Based on the final yield, each cell produced 18,000?±?6,800 particles of purified rAAV in 10-, 20-, 100-, and 200-liter cultures. Thus, with an average cell density of 4.32?×?106 cells/ml, ?1016 purified rAAV particles are produced from 100 to 200 liters. The downstream process resulted in about 20% recovery estimated from comparing the quantities of capsid protein antigen in the crude bioreactor material and in the final, purified product. The ease and reproducibility of rAAV production in 200-liter bioreactors suggest that the limit has not been reached, and 500-liter productions are planned. PMID:21381980

Cecchini, Sylvain; Virag, Tamas

2011-01-01

6

Grid'5000 for high-quality reproducible research Lucas Nussbaum  

E-print Network

Grid'5000 for high-quality reproducible research Lucas Nussbaum lucas.nussbaum@loria.fr Grid'5000 Lucas Nussbaum Grid'5000 for high-quality reproducible research 1 / 28 hal-01011403,version1-23Jun2014, on a scientific instrument Often a mix of both: In Physics In Computer Science Lucas Nussbaum Grid'5000 for high

Paris-Sud XI, Université de

7

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

8

Triploid planarian reproduces truly bisexually with euploid gametes produced through a different meiotic system between sex.  

PubMed

Although polyploids are common among plants and some animals, polyploidization often causes reproductive failure. Triploids, in particular, are characterized by the problems of chromosomal pairing and segregation during meiosis, which may cause aneuploid gametes and results in sterility. Thus, they are generally considered to reproduce only asexually. In the case of the Platyhelminthes Dugesia ryukyuensis, populations with triploid karyotypes are normally found in nature as both fissiparous and oviparous triploids. Fissiparous triploids can also be experimentally sexualized if they are fed sexual planarians, developing both gonads and other reproductive organs. Fully sexualized worms begin reproducing by copulation rather than fission. In this study, we examined the genotypes of the offspring obtained by breeding sexualized triploids and found that the offspring inherited genes from both parents, i.e., they reproduced truly bisexually. Furthermore, meiotic chromosome behavior in triploid sexualized planarians differed significantly between male and female germ lines, in that female germ line cells remained triploid until prophase I, whereas male germ line cells appeared to become diploid before entry into meiosis. Oocytes at the late diplotene stage contained not only paired bivalents but also unpaired univalents that were suggested to produce diploid eggs if they remained in subsequent processes. Triploid planarians may therefore form euploid gametes by different meiotic systems in female and male germ lines and thus are be able to reproduce sexually in contrast to many other triploid organisms. PMID:24402417

Chinone, Ayako; Nodono, Hanae; Matsumoto, Midori

2014-06-01

9

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.

10

High resolution optics combined with high spatial reproducibility in flow  

SciTech Connect

Accurate sizing in flow using optical methods generally requires high resolution optics and specially designed flow systems. Flow systems developed by this group have following features: (a) double sheath configuration for optical index match, (b) no curved optical surface in the sensing area, (c) gradual hydrodynamic focusing over a long distance to minimize mechanical shearing, (d) precision spatial positioning of cells by reducing suspension fluid diameter to a cell diameter or less, (e) total thickness between outer surfaces of the flow chamber at the viewing area of 1.5 mm or less. Cells intersect a laser light beam focussed go circular as well as elliptical cross-sections or 1 micron or less in diameter. Cellular extinction is monitored during transit through the beam. Cell length is derived from the time for flight measurement and corrected for absolute values by continuous velocity reference using a second laser beam intersecting the cell stream at a predetermined distance. This second spot may be circular or elliptical, of a different polarization and/or frequency. Simultaneous fluorescence intensity and diameter measurements were performed on test particles using different optical geometries. The influence of the particle structure on fluorescence measurements is demonstrated where high resolution sizing is required at the same time.

Eisert, W.G.

1981-01-01

11

Efé cacy and Reproducibility of a Produce Wash in Killing Salmonella on the Surface of Tomatoes Assessed with a Proposed Standard Method for Produce Sanitizers  

Microsoft Academic Search

The reproducibility of a method developed to evaluate point-of-use sanitizers for fresh produce was tested at three different laboratories. Mixtures of é ve Salmonella serotypes were inoculated on the surface of ripe tomatoes. After the inoculum was dry, tomatoes were placed inside a plastic bag and sprayed with sterile USP water, Dey and Engley (D\\/E) neutralizer broth, or a prototype

LINDA J. HARRIS; LARRY R. BEUCHAT; THERESA M. KAJS; THOMAS E. WARD; CHARLES H. TAYLOR

12

A high-reproducibility and high-accuracy method for automated topic classification  

E-print Network

Much of human knowledge sits in large databases of unstructured text. Leveraging this knowledge requires algorithms that extract and record metadata on unstructured text documents. Assigning topics to documents will enable intelligent search, statistical characterization, and meaningful classification. Latent Dirichlet allocation (LDA) is the state-of-the-art in topic classification. Here, we perform a systematic theoretical and numerical analysis that demonstrates that current optimization techniques for LDA often yield results which are not accurate in inferring the most suitable model parameters. Adapting approaches for community detection in networks, we propose a new algorithm which displays high-reproducibility and high-accuracy, and also has high computational efficiency. We apply it to a large set of documents in the English Wikipedia and reveal its hierarchical structure. Our algorithm promises to make "big data" text analysis systems more reliable.

Lancichinetti, Andrea; Wang, Jane X; Acuna, Daniel; Körding, Konrad; Amaral, Luís A Nunes

2014-01-01

13

High-throughput miniaturized bioreactors for cell culture process development: reproducibility, scalability, and control.  

PubMed

Decreasing the timeframe for cell culture process development has been a key goal toward accelerating biopharmaceutical development. Advanced Microscale Bioreactors (ambr™) is an automated micro-bioreactor system with miniature single-use bioreactors with a 10-15 mL working volume controlled by an automated workstation. This system was compared to conventional bioreactor systems in terms of its performance for the production of a monoclonal antibody in a recombinant Chinese Hamster Ovary cell line. The miniaturized bioreactor system was found to produce cell culture profiles that matched across scales to 3 L, 15 L, and 200 L stirred tank bioreactors. The processes used in this article involve complex feed formulations, perturbations, and strict process control within the design space, which are in-line with processes used for commercial scale manufacturing of biopharmaceuticals. Changes to important process parameters in ambr™ resulted in predictable cell growth, viability and titer changes, which were in good agreement to data from the conventional larger scale bioreactors. ambr™ was found to successfully reproduce variations in temperature, dissolved oxygen (DO), and pH conditions similar to the larger bioreactor systems. Additionally, the miniature bioreactors were found to react well to perturbations in pH and DO through adjustments to the Proportional and Integral control loop. The data presented here demonstrates the utility of the ambr™ system as a high throughput system for cell culture process development. PMID:24449637

Rameez, Shahid; Mostafa, Sigma S; Miller, Christopher; Shukla, Abhinav A

2014-01-01

14

High resolution downscaling with WRF: reproducing observed climate in high topography islands  

NASA Astrophysics Data System (ADS)

Isolated islands are specially vulnerable to climate change. However, their climate is generally not explicitly reproduced in GCMs, or even in most Regional Climate Models, due to their size and complex topography. On the other hand, the isolated nature of their location may allow the use of high resolution in domains of limited size, with oceanic boundary conditions all around directly given by a GCM. It is important to know, though, how far do we need to go in horizontal resolution in order to reproduce the main features of observed climate and if the proposed method has significant advantages in relation to simpler procedures. This paper uses the WRF model to downscale global fields given by ERA-Interim and by three runs of the EC-Earth Climate Model (Hazeleger et al 2010): a control run representing the 1961-1990 climate, and two scenario runs corresponding to scenarios RCP4.5 and RCP8.5 up to the end of the 21st century. The WRF simulations builds on experience reproducing the climate in Iberia, at 9km horizontal resolution (Soares et al 2012, Cardoso et al 2013), which resulted in a good match with observations not only in what concerns the mean values of temperature and precipitation, but also the statistical distribution of high rank quantiles of daily precipitation (up to percentile 99.9). Here the WRF model is used on a nested grid configuration, with a larger domain simulated at 27km resolution and an inner domain at 6km. The cases of Madeira and Azores, 11 islands of different sizes in the subtropical North Atlantic, are simulated. Broadly speaking, results indicate significant improvements in the representation of observed precipitation in all islands in the ERA-Interim period, at the highest resolution. In the case of Madeira, the largest and bulkiest of the set, the improvement is the most remarkable, whereas in smaller islands there is a suggestion that the used resolution is still too coarse. The excellent results obtained by WRF in the Madeira ERA-Interim case indicate the ability of this model to perform as a regional climate model at high resolution, a requirement for the explicit simulation of climate in many isolated islands. Results obtained in the control and scenario runs are also analyzed, indicating significant changes in the precipitation climate in Madeira Island, and more subtle changes in the Azores. Finally, the WRF results are compared against two alternative downscaling techniques using an air mass transformation model and the precipitation model of Smith and Barstad (2005) References Barstad I, Smith RD (2005) Journal of Hydrometeorology 6, 85-99. Cardoso et al (2012) International Journal of Climatology, DOI: 10.1002/joc.361 Hazeleger et al (2010), Bulletim of the American Meteorological Society, 91, 1357-1363 . doi: 10.1175/2010BAMS2877.1 Soares et al (2012) Climate Dynamics, DOI: 10.1007/s00382-012-1315-2.

Miranda, P. M.; Tome, R.; Azevedo, E. B.; Teixeira, M.

2013-12-01

15

Month-to-month and year-to-year reproducibility of high frequency QRS ECG signals  

NASA Technical Reports Server (NTRS)

High frequency electrocardiography analyzing the entire QRS complex in the frequency range of 150 to 250 Hz may prove useful in the detection of coronary artery disease, yet the long-term stability of these waveforms has not been fully characterized. Therefore, we prospectively investigated the reproducibility of the root mean squared voltage, kurtosis, and the presence versus absence of reduced amplitude zones in signal averaged 12-lead high frequency QRS recordings acquired in the supine position one month apart in 16 subjects and one year apart in 27 subjects. Reproducibility of root mean squared voltage and kurtosis was excellent over these time intervals in the limb leads, and acceptable in the precordial leads using both the V-lead and CR-lead derivations. The relative error of root mean squared voltage was 12% month-to-month and 16% year-to-year in the serial recordings when averaged over all 12 leads. Reduced amplitude zones were also reproducible up to a rate of 87% and 81%, respectively, for the month-to-month and year-to-year recordings. We conclude that 12-lead high frequency QRS electrocardiograms are sufficiently reproducible for clinical use.

Batdorf, Niles J.; Feiveson, Alan H.; Schlegel, Todd T.

2004-01-01

16

Month-to-Month and Year-to-Year Reproducibility of High Frequency QRS ECG signals  

NASA Technical Reports Server (NTRS)

High frequency (HF) electrocardiography analyzing the entire QRS complex in the frequency range of 150 to 250 Hz may prove useful in the detection of coronary artery disease, yet the long-term stability of these waveforms has not been fully characterized. We therefore prospectively investigated the reproducibility of the root mean squared (RMS) voltage, kurtosis, and the presence versus absence of reduced amplitude zones (RAzs) in signal averaged 12-lead HF QRS recordings acquired in the supine position one month apart in 16 subjects and one year apart in 27 subjects. Reproducibility of RMS voltage and kurtosis was excellent over these time intervals in the limb leads, and acceptable in the precordial leads using both the V-lead and CR-lead derivations. The relative error of RMS voltage was 12% month-to-month and 16% year-to-year in the serial recordings when averaged over all 12 leads. RAzs were also reproducible at a rate of up to 87% and 8 1 %, respectively, for the month-to-month and year-to-year recordings. We conclude that 12-lead HF QRS electrocardiograms are sufficiently reproducible for clinical use.

Batdorf, Niles; Feiveson, Alan H.; Schlegel, Todd T.

2006-01-01

17

Highly reproducible hybridization assay of zeptomole DNA based on adsorption of nanoparticle-bioconjugate.  

PubMed

A nanoparticle-bioconjugate was formed by homogeneous hybridization of one polynucleotide target with two oligonucleotide probes labelled by thiol and a nanoparticle, respectively. Deposition of the nanoparticle-bioconjugate on a gold surface by thiol-gold reaction was monitored in situ by quartz crystal microbalance (QCM) and applied for flow analysis of zeptomole amounts of polynucleotide. The formation in solution and adsorption of thiolated conjugates on gold could be fast, uniform and effective, and has been successfully exploited to construct a highly reproducible and sensitive platform for detection of target sequences. Being more rapid, reproducible, sensitive and amenable to automation than previously reported microgravimetric hybridization assays, this technology has great promise for practical applications in molecular diagnostics. PMID:16284656

Mo, Zhihong; Wang, Hongli; Liang, Yulong; Liu, Fengwei; Xue, Yongxin

2005-12-01

18

Highly reproducible planar Sb2S3-sensitized solar cells based on atomic layer deposition.  

PubMed

A high-quality Sb2S3 thin-absorber with controllable thickness was reproducibly formed by atomic layer deposition (ALD) technique. Compared with conventional chemical bath deposition (CBD), the Sb2S3 absorber deposited by ALD did not contain oxide or oxygen impurities and showed a very uniform thickness of Sb2S3 absorbers formed on a rough surface of dense blocking TiO2/F-doped SnO2 (bl-TiO2/FTO) substrate. The planar ALD-Sb2S3 solar cells comprised of Au/Poly-3-hexylthiophene/ALD-Sb2S3/bl-TiO2/FTO showed significantly improved power conversion efficiency of 5.77% at 1 sun condition and narrow efficiency deviation, whereas the planar CBD-Sb2S3 solar cells exhibited 2.17% power conversion efficiency. The high efficiency and good reproducibility of ALD-Sb2S3 solar cell devices is attributed to reduced backward recombination because of the inhibition of oxide defects within ALD-Sb2S3 absorber and the conformal deposition of very uniform Sb2S3 absorbers on the blocking TiO2 surface by ALD process. PMID:25350778

Kim, Dae-Hwan; Lee, Sang-Ju; Park, Mi Sun; Kang, Jin-Kyu; Heo, Jin Hyuck; Im, Sang Hyuk; Sung, Shi-Joon

2014-11-01

19

Reproducible, high-throughput synthesis of colloidal nanocrystals for optimization in multidimensional parameter space.  

PubMed

While colloidal nanocrystals hold tremendous potential for both enhancing fundamental understanding of materials scaling and enabling advanced technologies, progress in both realms can be inhibited by the limited reproducibility of traditional synthetic methods and by the difficulty of optimizing syntheses over a large number of synthetic parameters. Here, we describe an automated platform for the reproducible synthesis of colloidal nanocrystals and for the high-throughput optimization of physical properties relevant to emerging applications of nanomaterials. This robotic platform enables precise control over reaction conditions while performing workflows analogous to those of traditional flask syntheses. We demonstrate control over the size, size distribution, kinetics, and concentration of reactions by synthesizing CdSe nanocrystals with 0.2% coefficient of variation in the mean diameters across an array of batch reactors and over multiple runs. Leveraging this precise control along with high-throughput optical and diffraction characterization, we effectively map multidimensional parameter space to tune the size and polydispersity of CdSe nanocrystals, to maximize the photoluminescence efficiency of CdTe nanocrystals, and to control the crystal phase and maximize the upconverted luminescence of lanthanide-doped NaYF(4) nanocrystals. On the basis of these demonstrative examples, we conclude that this automated synthesis approach will be of great utility for the development of diverse colloidal nanomaterials for electronic assemblies, luminescent biological labels, electroluminescent devices, and other emerging applications. PMID:20387807

Chan, Emory M; Xu, Chenxu; Mao, Alvin W; Han, Gang; Owen, Jonathan S; Cohen, Bruce E; Milliron, Delia J

2010-05-12

20

Evaluation of a high-order Ambisonics decoder for irregular loudspeaker arrays through reproduced field measurements.  

PubMed

High-order Ambisonics (HOA) is a sound field reproduction technique that defines a scalable and system-independent encoding of spatial sound information. Decoding of HOA signals for reproduction using loudspeaker arrays can be a difficult task if the angular spacing between adjacent loudspeakers, as observed from the listening position, is not uniform. In this research, one of such systems is considered: a 157-channel irregular loudspeaker array. The array is used to reproduce simple HOA-encoded sound fields. Three HOA decoding methods are evaluated: two conventional ones and a recently proposed decoder designed for irregular loudspeaker arrays. Reproduction accuracy is compared by directly measuring the sound pressure around the listening position, the so-called sweet spot. Coarse-resolution sound field measurements give an approximate size for the listening region generated by the different methods. In addition, dummy head recordings are used to evaluate interaural level and phase differences. The results are used to estimate the accuracy of the system when presenting spatial sound. This study shows the importance of selecting a proper decoding method to reproduce HOA with irregular loudspeaker arrays. This is emphasized by the use of an actual loudspeakers system instead of a computer simulation, a common shortcoming of previous studies. PMID:25235979

Trevino Lopez, Jorge A; Okamoto, Takuma; Iwaya, Yukio; Sakamoto, Shuichi; Suzuki, Yo-Iti

2014-04-01

21

Pathological Scoring of PTEN Immunohistochemistry in Endometrial Carcinoma is Highly Reproducible  

PubMed Central

Endometrial carcinomas show frequent PTEN-PI3K pathway abnormalities, and there are currently multiple trials focused on PI3K pathway inhibitors in endometrial carcinoma patients. PTEN immunohistochemistry may help select patients with potential for response to targeted therapy making it important to develop and validate this stain in formalin-fixed, paraffin embedded tissue. Immunohistochemistry for PTEN was performed and scored independently on 118 cases of endometrial carcinomas from 2 cancer centers using monoclonal DAKO 6H2.1antibody. Cases were scored as positive, negative or heterogeneous; reproducibility of PTEN staining and interpretation was assessed. Overall interobserver agreement was good (weighted ? = 0.80), with 82% concordance, similar for non endometrioid (81%) and endometrioid carcinomas (85%). 21 of 118 cases showed discrepant results (17%); that resulted from differences in interpretation and not staining. Our study shows that evaluation of PTEN loss by immunohistochemistry is highly reproducible with the application of standard immunohistochemical techniques and simple scoring criteria. PMID:22123723

Garg, Karuna; Broaddus, Russell R.; Soslow, Robert A; Urbauer, Diana L.; Levine, Douglas A; Djordjevic, Bojana

2014-01-01

22

Reproducible fabrication of stable small nano Pt with high activity for sensor applications.  

PubMed

Pt nanoparticles with an average size of 2-3 nm in diameter were reproducibly synthesized by reduction of H?PtCl? solution containing inositol hexaphosphate (IP?) as the stabilizing agent. Single crystals with Pt(111) faces of the resulting cubic nanoparticles were revealed by the electron diffraction pattern. The PtNPs-IP? nanoparticles were used to modify an electrode as a nonenzymatic sensor for H?O? detection, exhibiting a fast response and high sensitivity. A low detection limit of 2.0 × 10?? M (S/N = 3) with two linear ranges between 2.4 × 10?? and 1.3 × 10?³ M (R² = 0.9987) and between 1.3 × 10?³ and 1.3 × 10?² M (R² = 0.9980) was achieved. The attractive electrochemical performance of PtNPs-IP? enables it to be employed as a promising material for the development of Pt-based analytical systems and other applications. PMID:23807200

Ye, Pingping; Guo, Xiaoyu; Liu, Guiting; Chen, Huifen; Pan, Yuxia; Wen, Ying; Yang, Haifeng

2013-07-26

23

High speed and reproducible analysis of nitrosamines by capillary electrophoresis with a sulfonated capillary.  

PubMed

Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half. PMID:17898509

Taga, Atsushi; Nishi, Tomoko; Honda, Yoshitaka; Sato, Atsushi; Terashima, Hiroyuki; Suzuki, Kentaro; Kodama, Shuji; Boki, Keito

2007-01-01

24

THE LHC CRYOMAGNET SUPPORTS IN GLASS-FIBER REINFORCED EPOXY: A LARGE SCALE INDUSTRIAL PRODUCTION WITH HIGH REPRODUCIBILITY IN PERFORMANCE  

SciTech Connect

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.; Parma, V. [CERN, European Organization for Nuclear Research Geneva, CH-1211 (Switzerland); Trigo, J. [EADS, CASA-Espacio, Madrid, Av. Aragon 28022 (Spain)

2008-03-03

25

Direct experimental occlusion of the distal middle cerebral artery induces high reproducibility of brain ischemia in mice.  

PubMed

Several investigators have used murine models to investigate the pathophysiology of brain ischemia. The focal ischemic model is a closer approximation to human stroke which includes a necrotic core, penumbra, and undamaged tissue. Occlusion of a unilateral artery, especially the middle cerebral artery (MCA), is performed in this model, but collateral circulation often induces variation of ischemic lesions both qualitatively and quantitatively. It is likely that the more proximal the artery which is unilaterally occluded is, the more inconsistent the outcomes. The present study was designed to examine the reproducibility of infarct lesion by distal or proximal artery occlusion. Direct occlusion of the distal MCA was performed and compared with unilateral common carotid artery occlusion (CCAO) in C57BL/6 mice. Direct MCA occlusion (MCAO) consistently induced ischemic lesions in cortical areas. All model animals (n=14) survived 24 h after occlusion, and exhibited a maximum infarct volume (20.0 +/- 5.0%). In contrast, permanent and transient unilateral CCAO models had mortality rates of 62.5 and 25.0%, and showed severe to absent lesions with the infarct volumes of 29.0 +/- 20.8 and 33.2 +/- 24.2%, respectively. In conclusion, distal MCAO produces high reproducibility of ischemic insults and survivability compared to unilateral CCAO. Thus, distal MCAO is a useful method for the focal ischemic model. PMID:19151508

Kuraoka, Mutsuki; Furuta, Takahisa; Matsuwaki, Takashi; Omatsu, Tsutomu; Ishii, Yoshiyuki; Kyuwa, Shigeru; Yoshikawa, Yasuhiro

2009-01-01

26

For personal use. Only reproduce with permission from Elsevier Ltd. Most current candidate HIV vaccines seem to produce little  

E-print Network

vaccines seem to produce little protection against infection, but reduce viral load and slow the decline in CD4 lymphocyte numbers. Such disease- modifying vaccines could potentially provide important the following question: could disease-modifying HIV vaccines cause population-level perversity (ie, increase

Blower, Sally

27

State-of-the-art exposure chamber for highly controlled and reproducible THz biological effects studies  

NASA Astrophysics Data System (ADS)

Terahertz (THz) imaging and sensing technologies are increasingly being used at international airports for security screening purposes and at major medical centers for cancer and burn diagnosis. The emergence of new THz applications has directly resulted in an increased interest regarding the biological effects associated with this frequency range. Knowledge of THz biological effects is also desired for the safe use of THz systems, identification of health hazards, and development of empirically-based safety standards. In this study, we developed a state-of-the-art exposure chamber that allowed for highly controlled and reproducible studies of THz biological effects. This innovative system incorporated an industry grade cell incubator system that permitted a highly controlled exposure environment, where temperatures could be maintained at 37 °C +/- 0.1 °C, carbon dioxide (CO2) levels at 5% +/- 0.1%, and relative humidity (RH) levels at 95% +/- 1%. To maximize the THz power transmitted to the cell culture region inside the humid incubator, a secondary custom micro-chamber was fabricated and incorporated into the system. This micro-chamber shields the THz beam from the incubator environment and could be nitrogen-purged to eliminate water absorption effects. Additionally, a microscope that allowed for real-time visualization of the live cells before, during, and after THz exposure was integrated into the exposure system.

Cerna, Cesario Z.; Elam, David P.; Echchgadda, Ibtissam; Sloan, Mark A.; Wilmink, Gerald J.

2014-03-01

28

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. PMID:22035967

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

2011-01-01

29

High interlaboratory reproducibility of DNA sequence-based typing of bacteria in a multicenter study  

Microsoft Academic Search

Current DNA amplification-based typing methods for bacterial pathogens often lack interlaboratory reproducibility. In this international study, DNA sequence-based typing of the Staphylococcus aureus protein A gene (spa, 110 to 422 bp) showed 100% intra- and interlaboratory reproducibility without extensive harmonization of protocols for 30 blind-coded S. aureus DNA samples sent to 10 laboratories. Specialized software for automated sequence analysis ensured

Marta Aires-de-Sousa; K Boye; H de Lencastre; A Deplano; M C Enright; J Etienne; A Friedrich; D Harmsen; A Holmes; Xander W Huijsdens; A M Kearns; A Mellmann; H Meugnier; J K Rasheed; Emile Spalburg; B Strommenger; M J Struelens; F C Tenover; J Thomas; U Vogel; H Westh; J Xu; W Witte

2007-01-01

30

Method of producing high temperature superconductor wires  

Microsoft Academic Search

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

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

1992-01-01

31

Quantitative optical recognition of highly reproducible ultrathin oxide films in microelectrochemical anodization.  

PubMed

Automatized microelectrochemical investigations are achieved using a scanning droplet cell. The area reproducibility for a 100 mum oxide spot is found to be better than 1%, a value typically difficult to reach even in macroscopic samples. A systematic change in color appearance is seen for oxide films with a thickness ranging from 14 to 27 nm. Analysis of optical images yields a strictly linear relation between relative transmission and anodization charge and thus allows determination of the oxide thickness with a remarkable precision better than 0.5 nm at an absolute film thickness value that is at least a factor of 20 smaller than the wavelength of light. PMID:19405702

Mardare, Andrei Ionut; Hassel, Achim Walter

2009-04-01

32

A Highly Reproducible Bolus Immobilization Technique for the Treatment of Scalp Malignancies  

SciTech Connect

Radiation treatment of scalp malignancies can be a challenge due to the multiple curved surfaces to which homogenous dose must be delivered. The most readily available techniques utilize linear accelerator-based technique of opposed lateral electron field abutting opposed lateral photon field with central blocking. Bolus material is used to achieve adequate skin dose. Although plans to add bolus material often occur in the virtual setting during treatment planning, the practical aspects of reproducibly maintain the bolus material along curved surfaces during the day-to-day patient setup can be a challenge. We present a case of a patient with squamous cell carcinoma of the scalp with neck node involvement treated with surgery followed by adjuvant radiotherapy. We demonstrate a unique immobilization technique that maintains the bolus material on the aquaplast mesh adherent to the patient's scalp as well as the neck. TomoTherapy with daily megavoltage computed tomography (CT) scan was utilized to verify the daily bolus position. We were able to maintain a 95% reproducibility rate. This technique reliably maintains the bolus material on the desired locations with minimum adjustments and manipulation by the therapist and is a technique that can be universally adapatable for conventional radiotherapy or intensity modulated radiation therapy (IMRT) techniques.

Lin, Steven H.; Latronico, Diane; Teslow, Terrance [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States); Bajaj, Gopal K. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD (United States)], E-mail: gbajaj1@jhmi.edu

2008-04-01

33

A highly reproducible bolus immobilization technique for the treatment of scalp malignancies.  

PubMed

Radiation treatment of scalp malignancies can be a challenge due to the multiple curved surfaces to which homogenous dose must be delivered. The most readily available techniques utilize linear accelerator-based technique of opposed lateral electron field abutting opposed lateral photon field with central blocking. Bolus material is used to achieve adequate skin dose. Although plans to add bolus material often occur in the virtual setting during treatment planning, the practical aspects of reproducibly maintain the bolus material along curved surfaces during the day-to-day patient setup can be a challenge. We present a case of a patient with squamous cell carcinoma of the scalp with neck node involvement treated with surgery followed by adjuvant radiotherapy. We demonstrate a unique immobilization technique that maintains the bolus material on the aquaplast mesh adherent to the patient's scalp as well as the neck. TomoTherapy with daily megavoltage computed tomography (CT) scan was utilized to verify the daily bolus position. We were able to maintain a 95% reproducibility rate. This technique reliably maintains the bolus material on the desired locations with minimum adjustments and manipulation by the therapist and is a technique that can be universally adaptable for conventional radiotherapy or intensity modulated radiation therapy (IMRT) techniques. PMID:18262120

Lin, Steven H; Latronico, Diane; Teslow, Terrance; Bajaj, Gopal K

2008-01-01

34

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

35

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

36

Controlled reproducible alignment of cone targets and mitigation of preplasma in high intensity laser interactions  

SciTech Connect

The use of cone targets in high intensity laser-plasma experiments has been of recent interest because of their potential use in integrated fast ignition experiments. Simpler experiments provide a good avenue for understanding the underlying physics, however precise control of the alignment along with good pointing accuracy is of crucial importance. While on big laser facilities target alignment is done precisely with several microscopes, it is not always the case on smaller facilities. This can have a detrimental effect on the quality of the results. We have developed and characterized a method for accurate alignment of intense laser pulses into a cone target. This, along with optimal positioning of the focus compared to the tip, efficiently uses the shape of the target to microfocus the laser light and concentrates the hot electrons in the tip, and can mitigate preplasma issues.

Renard-Le Galloudec, Nathalie [Nevada Terawatt Facility, Department of Physics, University of Nevada, Reno, Nevada 89521-0042 (United States); Cho, Byoung-Ick; Ditmire, Todd [Texas Center for High Intensity Laser Science, Department of Physics, University of Texas, Austin, Texas 78712-0263 (United States); Osterholz, Jens [Texas Center for High Intensity Laser Science, Department of Physics, University of Texas, Austin, Texas 78712-0263 (United States); Institute of Laser and Plasmaphysics, Heinrich-Heine-University Geb. 25.33 Universitaetsstr. 1, 40225, Duesseldorf (Germany)

2008-08-15

37

Highly reproducible memory effect of organic multilevel resistive-switch device utilizing graphene oxide sheets/polyimide hybrid nanocomposite  

NASA Astrophysics Data System (ADS)

The functionalization of graphene oxide (GO) sheets with polyimide (PI) enables the layer-by-layer fabrication of a GO-PI hybrid resistive-switch device and leads to high reproducibility of the memory effect. The current-voltage curves for the as-fabricated device exhibit multilevel resistive-switch properties under various reset voltages. The capacitance-voltage characteristics for a capacitor based on GO-PI nanocomposite indicate that the electrical switching may originate from the charge trapping in GO sheets. The high device-to-device uniformity and unique memory properties of the device make it an attractive candidate for applications in next-generation high-density nonvolatile flash memories.

Wu, Chaoxing; Li, Fushan; Zhang, Yongai; Guo, Tailiang; Chen, Ting

2011-07-01

38

Producing and Marketing High-Value Calves  

E-print Network

. The prices received for cattle based upon breed, breed combinations or type are not always warranted, but the careful producer always considers the types of calves buyers are demanding. Breeds and mating programs should be planned carefully because short... at weaning. This can be offset by using growth implants to increase the weaning weights of steer calves. Calf Crop Management After producing top-quality calves that will be acceptable in the market, producers must manage those calves properly to avoid...

Cleere, Jason; Boleman, Larry L.

2006-06-22

39

Highly reproducible laser beam scanning device for an internal source laser desorption microprobe Fourier transform mass spectrometer  

NASA Astrophysics Data System (ADS)

Traditionally, mass spectrometry has relied on manipulating the sample target to provide scanning capabilities for laser desorption microprobes. This has been problematic for an internal source laser desorption Fourier transform mass spectrometer (LD-FTMS) because of the high magnetic field (7 Tesla) and geometric constraints of the superconducting magnet bore. To overcome these limitations, we have implemented a unique external laser scanning mechanism for an internal source LD-FTMS. This mechanism provides adjustable resolution enhancement so that the spatial resolution at the target is not limited to that of the stepper motors at the light source (˜5 ?m/step). The spatial resolution is now limited by the practical optical diffraction limit of the final focusing lens. The scanning mechanism employs a virtual source that is wavelength independent up to the final focusing lens, which can be controlled remotely to account for focal length dependence on wavelength. A binary index provides an automatic alignment feature. The virtual source is located ˜9 ft from the sample; therefore, it is completely outside of the vacuum system and beyond the 50 G line of the fringing magnetic field. To eliminate reproducibility problems associated with vacuum pump vibrations, we have taken advantage of the magnetic field inherent to the FTMS to utilize Lenz's law for vibrational dampening. The LD-FTMS microprobe has exceptional reproducibility, which enables successive mapping sequences for depth-profiling studies.

Scott, Jill R.; Tremblay, Paul L.

2002-03-01

40

High-resolution episcopic microscopy data-based measurements of the arteries of mouse embryos: evaluation of significance and reproducibility under routine conditions.  

PubMed

Defining the role of genes in the genesis of congenital cardiovascular defects involves comparisons of the diameters of arteries measured in wild-type and genetically engineered mouse embryos. This study aims at evaluating the significance and reproducibility of measurements of the diameters of the great intrathoracic arteries of mouse embryos, as produced under routine conditions, by employing a recently suggested measuring method. Using high-resolution episcopic microscopy, we generated digital volume data of 60 mouse embryos (voxel size 1.07 × 1.07 × 2 ?m(3)) of developmental stage 23 according to Theiler. We randomly split the 60 data sets into two groups of 30 and assigned each group to a diploma student. In addition, an experienced scientist received 12 randomly selected specimens of each group. Independently, the researchers created three-dimensional models of the intrathoracic arteries and identified comparable measurement positions along the ascending aorta, pulmonary trunk and descending aorta. At each position, they defined virtual resections cutting through the volume data perpendicular to the longitudinal axis of the artery. In the virtual resections, the researchers measured the perimeter of the lumen of the artery. The diameter was calculated from the perimeter. Then, we performed statistic comparisons of the diameters measured in micrometres and of the ratio of each measured diameter and the diameter of the ascending aorta. Comparisons of the ratios did not reveal statistically significant differences between the measurements created by the different scientists. We assume that the used measuring protocol is highly robust and produces reproducible and significant results under routine conditions. PMID:21997436

Geyer, Stefan H; Maurer, Barbara; Pötz, Lorenz; Singh, Jagdeep; Weninger, Wolfgang J

2012-01-01

41

High ethanol producing derivatives of Thermoanaerobacter ethanolicus  

DOEpatents

Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).

Ljungdahl, L.G.; Carriera, L.H.

1983-05-24

42

Electron beam chemistry produces high purity metals  

NASA Technical Reports Server (NTRS)

Application of radiation chemistry for deposition of metals by irradiation of aqueous solutions with high energy electrons is presented. Design of reaction vessel for irradiation of solution is illustrated. Features of radiochemical technique and procedures followed are described.

Philipp, W. H.; May, C. E.; Marsik, S. J.; Lad, R. A.

1972-01-01

43

High-adhesive superhydrophobic 3D nanostructured silver films applied as sensitive, long-lived, reproducible and recyclable SERS substrates  

NASA Astrophysics Data System (ADS)

Silver films with different morphologies were chemically deposited by controlling the bath composition. It is found that the wettability and surface enhanced Raman scattering (SERS) properties were closely connected with the surface morphology. Due to the perfect 3D morphology and the 3D electromagnetic field enhanced by three types of nanogaps distributed uniformly, the 3D microball/nanosheet (MN) silver film shows better SERS properties than those of 2D nanosheets (NSs) and nanoparticles (NPs). The MN silver film showed high adhesive superhydrophobic properties after an oxidation process without any functionalization. It can hold the liquid droplet and trace the target molecules in a rather small volume. The SERS properties of the oxidized MN substrate were enhanced remarkably compared to those of the freshly prepared substrate because of the concentrating effect of the superhydrophobicity. The as-prepared 3D MN silver substrate has also exhibited good performances in reproducibility and reutilization which makes it a promising substrate for molecule tracing.Silver films with different morphologies were chemically deposited by controlling the bath composition. It is found that the wettability and surface enhanced Raman scattering (SERS) properties were closely connected with the surface morphology. Due to the perfect 3D morphology and the 3D electromagnetic field enhanced by three types of nanogaps distributed uniformly, the 3D microball/nanosheet (MN) silver film shows better SERS properties than those of 2D nanosheets (NSs) and nanoparticles (NPs). The MN silver film showed high adhesive superhydrophobic properties after an oxidation process without any functionalization. It can hold the liquid droplet and trace the target molecules in a rather small volume. The SERS properties of the oxidized MN substrate were enhanced remarkably compared to those of the freshly prepared substrate because of the concentrating effect of the superhydrophobicity. The as-prepared 3D MN silver substrate has also exhibited good performances in reproducibility and reutilization which makes it a promising substrate for molecule tracing. Electronic supplementary information (ESI) available: XRD patterns of three different substrates. XPS spectra of the MN silver film after modification. Raman spectra collected from 5 random points in the NP silver film. SERS spectra of 1 ?M 4-Mpy absorbed on different substrates. XPS O 1s spectra of the MN surface before and after storage. SERS spectra of 4 ?L 10-12 R6G absorbed onto the freshly prepared MN substrate. Raman spectra obtained on the solid R6G. SERS spectra obtained on the surface of the oxidized MN substrate after rinsing with deionized water. See DOI: 10.1039/c4nr02198c

Wu, Yunwen; Hang, Tao; Komadina, Jason; Ling, Huiqin; Li, Ming

2014-07-01

44

Large-area fabrication of highly reproducible surface enhanced Raman substrate via a facile double sided tape-assisted transfer approach using hollow Au-Ag alloy nanourchins  

NASA Astrophysics Data System (ADS)

Ideally, a SERS substrate should possess super signal amplification, high uniformity and reproducibility. Up to now, an emphasis on reproducibility and uniformity has been crucial to ensure consistent chemical detection sensitivity across the surface of a SERS substrate. Here we demonstrate a simple and facile double sided tape-assisted transfer method to fabricate surface enhanced Raman scattering (SERS) substrates with prominent performance using hollow Au-Ag alloy nanourchins (HAAA-NUs). Such a large area, closely-packed flat film of the HAAA-NUs with a high density of ``hot spots'' exhibits a high SERS activity and reproducibility, simultaneously. The AFM-correlated nano-Raman and the point by point scanning of SERS signals verify the excellent spatial uniformity and reproducibility with a low relative standard deviation (RSD) less than 15% using crystal violet as probe molecule at the concentrations of 1 × 10-8 M and 1 × 10-10 M. The SERS signals of Sudan dye at a 1 × 10-8 M concentration also show high reproducibility with a low RSD of 13.8%. This facile protocol presented here could lead to a high quality SERS substrate and open tremendous potential for various applications.Ideally, a SERS substrate should possess super signal amplification, high uniformity and reproducibility. Up to now, an emphasis on reproducibility and uniformity has been crucial to ensure consistent chemical detection sensitivity across the surface of a SERS substrate. Here we demonstrate a simple and facile double sided tape-assisted transfer method to fabricate surface enhanced Raman scattering (SERS) substrates with prominent performance using hollow Au-Ag alloy nanourchins (HAAA-NUs). Such a large area, closely-packed flat film of the HAAA-NUs with a high density of ``hot spots'' exhibits a high SERS activity and reproducibility, simultaneously. The AFM-correlated nano-Raman and the point by point scanning of SERS signals verify the excellent spatial uniformity and reproducibility with a low relative standard deviation (RSD) less than 15% using crystal violet as probe molecule at the concentrations of 1 × 10-8 M and 1 × 10-10 M. The SERS signals of Sudan dye at a 1 × 10-8 M concentration also show high reproducibility with a low RSD of 13.8%. This facile protocol presented here could lead to a high quality SERS substrate and open tremendous potential for various applications. Electronic supplementary information (ESI) available: Fig. S1-S6. See DOI: 10.1039/c3nr05840a

Liu, Zhen; Cheng, Lin; Zhang, Lei; Jing, Chao; Shi, Xin; Yang, Zhongbo; Long, Yitao; Fang, Jixiang

2014-02-01

45

Reproducible Preparation of Au/TS-1 with High Reaction Rate for Gas Phase Epoxidation of Propylene  

SciTech Connect

A refined and reliable synthesis procedure for Au/TS-1(Si/Ti molar ratio {approx}100) with high reaction rate for the direct gas phase epoxidation of propylene has been developed by studying the effects of pH of the gold slurry solution, mixing time, and preparation temperature for deposition precipitation (DP) of Au on TS-1 supports. Au/TS-1 catalysts prepared at optimal DP conditions (pH {approx} 7.3, mixing for 9.5 h, room temperature) showed an average PO rate {approx} 160 g{sub PO} h{sup -1} kg{sub Cat}{sup -1} at 200 C at 1 atm. A reproducibility better than {+-}10% was demonstrated by nine independent samples prepared at the same conditions. These are the highest rates yet reported at 200 C. No visible gold particles were observed by the HRTEM analysis in the fresh Au/TS-1 with gold loading up to {approx}0.1 wt%, indicating that the gold species were smaller than 1 nm. Additionally, the rate per gram of Au and the catalyst stability increased as the Au loading decreased, giving a maximum value of 500 g{sub PO} h{sup -1} g{sub Au}{sup -1}, and Si/Ti molar ratios of {approx}100 gave the highest rates.

Lee W. S.; Stach E.; Akatay, M.C.; Ribeiro, F.H.; Delgass, N.

2012-03-01

46

A highly reproducible and straightforward method to perform in vivo ocular enucleation in the mouse after eye opening.  

PubMed

Enucleation or the surgical removal of an eye can generally be considered as a model for nerve deafferentation. It provides a valuable tool to study the different aspects of visual, cross-modal and developmental plasticity along the mammalian visual system(1-4). Here, we demonstrate an elegant and straightforward technique for the removal of one or both eyes in the mouse, which is validated in mice of 20 days old up to adults. Briefly, a disinfected curved forceps is used to clamp the optic nerve behind the eye. Subsequently, circular movements are performed to constrict the optic nerve and remove the eyeball. The advantages of this technique are high reproducibility, minimal to no bleeding, rapid post-operative recovery and a very low learning threshold for the experimenter. Hence, a large amount of animals can be manipulated and processed with minimal amount of effort. The nature of the technique may induce slight damage to the retina during the procedure. This side effect makes this method less suitable as compared to Mahajan et al. (2011)(5) if the goal is to collect and analyze retinal tissue. Also, our method is limited to post-eye opening ages (mouse: P10 - 13 onwards) since the eyeball needs to be displaced from the socket without removing the eyelids. The in vivo enucleation technique described in this manuscript has recently been successfully applied with minor modifications in rats and appears useful to study the afferent visual pathway of rodents in general. PMID:25350746

Aerts, Jeroen; Nys, Julie; Arckens, Lutgarde

2014-01-01

47

High-adhesive superhydrophobic 3D nanostructured silver films applied as sensitive, long-lived, reproducible and recyclable SERS substrates.  

PubMed

Silver films with different morphologies were chemically deposited by controlling the bath composition. It is found that the wettability and surface enhanced Raman scattering (SERS) properties were closely connected with the surface morphology. Due to the perfect 3D morphology and the 3D electromagnetic field enhanced by three types of nanogaps distributed uniformly, the 3D microball/nanosheet (MN) silver film shows better SERS properties than those of 2D nanosheets (NSs) and nanoparticles (NPs). The MN silver film showed high adhesive superhydrophobic properties after an oxidation process without any functionalization. It can hold the liquid droplet and trace the target molecules in a rather small volume. The SERS properties of the oxidized MN substrate were enhanced remarkably compared to those of the freshly prepared substrate because of the concentrating effect of the superhydrophobicity. The as-prepared 3D MN silver substrate has also exhibited good performances in reproducibility and reutilization which makes it a promising substrate for molecule tracing. PMID:24995507

Wu, Yunwen; Hang, Tao; Komadina, Jason; Ling, Huiqin; Li, Ming

2014-08-21

48

Quantitative Analysis with the Cameca Sxfive fe at High Lateral Resolution and High Reproducibility. Applications to Geochronology and Mineralogy.  

NASA Astrophysics Data System (ADS)

The development of the Schottky emitter and its implementation as electron source in Electron Microprobe has significantly improved the characterization of materials in earth sciences and in metallurgy. The strength of an Electron Probe Microanalysis (EPMA) is the ability to accurately measure and quantify element in traces at few 10's ppm level. The Field Emission (FE) Source allows trace element analysis with high beam currents thanks to the high brightness of the source and the excellent stability of the beam current, trading off spatial resolution. Of course, accuracy of major element quantification is maintained with a FE source. As X-rays are generated from a much larger diameter than the diameter of the incident electron beam, it is advised to work at low voltage and low beam current in order to take full advantage of the small spot sizes achievable with a Field Emission Source. Thus, the analytical resolution is not limited anymore by the beam diameter but only by the diameter of the X-ray emission volume. One of the advantages of the FE Source is to obtain fine focused electron beam at low beam voltage (?10 keV) while maintaining high and stable beam current. In these experimental conditions, the penetration depth of the primary electrons and thus the interaction volume- in which electrons are scattered and generate X-rays- decreases to sub-?m scale (compared to micron scale of the traditional Electron Microprobe at 15 or 20 keV). Thanks to WDS spectrometers with sub 10eV energy resolution, accurate quantitative analysis can be achieved even on sub micron phases at low beam energy and high lateral resolution using L- and M-Lines for heavy elements. This will be illustrated, in a first example, by measuring different areas in a Monazite grain. U, Pb and Th are quantitatively analyzed with high precision in order to characterize age domains. PIC PIC In the above example, several generations of monazite growth are represented in the quantified high-resolution X-ray maps. Of foremost interest is the high Y rim and fracture filling monazite (ca. ~1800 Ma) which has penetrated much older monazite (ca. ~2400 Ma). (Monazite from Boothia Peninsula, Nunavut, Canadian Artic) In a second example, quantification of small refractory phases (hibonite, grossite, perovskite, ...) formed by gas condensation in the solar nebula will be presented. Paris Meteorite is a stone classified by the Muséum National d'Histoire Naturelle as a CM chondrite. It contains chondrules and Calcium-aluminum-rich inclusions (CAI). These latter are materials formed at nearly the same time as the solar system i.e. 4.56 billion years ago. PIC PIC

Ehrke, Hans-Ulrich; Hombourger, Chrystel; Outrequin, Michel

2014-05-01

49

The Effect of Freeze/Thaw Cycles on Reproducibility of Metabolic Profiling of Marine Microalgal Extracts Using Direct Infusion High-Resolution Mass Spectrometry (HR-MS).  

PubMed

During normal sample preparation, storage in freezers and subsequent freeze/thaw cycles are commonly introduced. The effect of freeze/thaw cycles on the metabolic profiling of microalgal extracts using HR-MS was investigated. Methanolic extracts of monocultures of Arctic marine diatoms were analyzed immediately after extraction, after seven days of storage at -78 °C (one freeze/thaw cycle), and after additional seven days at -20 °C (two freeze/thaw cycles). Repeated direct infusion high-resolution mass spectrometry analysis of microalgae extracts of the same sample showed that reproducibility was ca. 90% when a fresh (unfrozen) sample was analyzed. The overall reproducibility decreased further by ca. 10% after the first freeze/thaw-cycle, and after one more freeze/thaw cycle the reproducibility decreased further by ca. 7%. The decrease in reproducibility after freeze-thaw cycles could be attributed to sample degradation and not to instrument variability. PMID:25314600

Eilertsen, Hans Chr; Huseby, Siv; Degerlund, Maria; Eriksen, Gunilla K; Ingebrigtsen, Richard A; Hansen, Espen

2014-01-01

50

Highly reproducible secondary electron imaging under electron irradiation using high-pass energy filtering in low-voltage scanning electron microscopy.  

PubMed

The reproducibility of contrast in secondary electron (SE) imaging during continuous electron irradiation, which caused surface contamination, was investigated using SE high-pass energy filtering in low-voltage scanning electron microscopy (SEM). According to high-pass energy-filtered imaging, dopant contrast in an indium phosphide remained remarkably stable during continuous electron irradiation although the contrast in unfiltered SE images decreased rapidly as a contamination layer was formed. Charge neutralization and the SE energy distributions indicate that the contamination layer induces a positive charge. This results in a decrease of low-energy SE emissions and reduced dopant contrast in unfiltered SE images. The retention of contrast was also observed in high-pass energy-filtered images of a gold surface. These results suggest that this imaging method can be widely used when SE intensities decrease under continuous electron irradiation in unfiltered SE images. Thus, high-pass energy-filtered SE imaging will be of a great assistance for SEM users in the reproducibility of contrast such as a quantitative dopant mapping in semiconductors. PMID:22364782

Tsurumi, Daisuke; Hamada, Kotaro; Kawasaki, Yuji

2012-04-01

51

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

52

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 1333 cm(-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

2013-11-15

53

Color holography to produce highly realistic three-dimensional images.  

PubMed

The 1964 publication by Emmett Leith and Juris Upatnieks [J. Opt. Soc. Am. 54, 1295 (1964)] introduced the possibility of using holograms to record three-dimensional (3D) objects. Since then, there has been an interest in creating display holograms, i.e., holograms primarily produced to show objects in 3D. More recently, full color holography has become a reality, which was predicted in the 1964 paper. To record a hologram in which both the 3D shape and the color of the object are accurately reproduced, at least three laser wavelengths are needed. By computer simulation of the holographic color rendering process, the required amount of laser wavelengths and their distribution within the visible electromagnetic spectrum have been investigated. The quality of a color hologram also depends on the properties of the recording material. The demand on a panchromatic material for color holography is described. Recording techniques for color holograms are presented as well as the future of color holography as the perfect 3D imaging technique. PMID:18239694

Bjelkhagen, Hans I; Mirlis, Evangelos

2008-02-01

54

A thermo-mechanical numerical scenario aiming at reproducing the metamorphic record of high-P rocks in the Palaeoproterozoic Eburnean orogeny.  

NASA Astrophysics Data System (ADS)

We test a scenario of the evolution of the Palaeoproterozoic Eburnean event characterising the Birimian Province (2.2-2.0 Ga, Western African Craton). A compilation of field data and petrological modeling indicates that an early thermal regime (M1, <10-15°/km) would have produced high-P greenschist to blueschist metamorphism assemblages, that most likely originated in thick sedimentary basins (depth>=20 km), and which would have formed above an original Birimian oceanic crust (possibly preaccreted forearc-backarcs systems). These assemblages record elevated pressures (P> 6-8 Kb) and are found in the thermal aureoles of CaO-poor granitoids. A second warmer, dominant geothermal gradient M2a (20-30°C/km) is found superimposed on M1, associated to greenschist-amphibolite metamorphic assemblages of moderate- to high-pressure rocks. We suggest that these rocks underwent exhumation processes in close association with continued regional shortening and granitoid intrusions. A thermo-mechanical model is proposed here for the Birimian crust, in which we choose an initial setting of oceanic arc resistant layer underlain by a layer of buoyant granitoids (CaO-rich TTGs). At the center of the model, this layer is itself overlain by a tectonically paired, mechanically weak basin several hundreds of kilometers wide (forearc-backarc system ?). Under applied compression, the model reproduces a mechanism of burial and distributed large-scale folding of this juvenile crust. As the oceanic arc and TTGs layers fold below the overlying hydrated sediments, their hinges deepen and they reach appropriate PT conditions to start melting and transform into a dominantly buoyant (CaO-poor) melt product, of lower viscosity and density (by ~5%). This newly formed material ascends and migrate laterally towards the upper parts of the buckle folds, and then pursues its ascension through the weak overlying sediments, within about 50 Myrs. This spatially periodical and "diapiric" mode of exhumation is capable to entrain preserved lower crustal material as well as re-heated sediments, upwards to about 10-15 km depth. A significant recycling of TTGs in the genesis of CaO-poor granitoid melts is thus expected. We suggest that final exhumation through the upper crust would have been completed by independent or subsequent transcurrent strike-slip zones along the mechanically weakened thermal aureoles of these granitoids. This scenario of exhumation significantly depends on initial layers thicknesses, viscosity and density contrasts, as well as on the timing of compression. These effects were numerically tested.

Gerbault, Muriel; Ganne, Jerome; Baratoux, Lenka; Dioh, Edmond; de Andrade, Vincent; Block, Sylvain; Perrouty, Stephane; Jessell, Marc

2013-04-01

55

How Do Beetles Reproduce?  

NSDL National Science Digital Library

Every living thing must be able to reproduce and make offspring. Most of us are familiar with how humans and mammals make babies, but do all creatures reproduce in the same way? Do insects, like the beetle, give birth to little insects? Also in: Français | Español

Drnevich, Jenny

2009-07-02

56

Can Population III Stars at High Redshifts produce GRB's?  

E-print Network

Gamma ray bursts are the most luminous physical phenomena in the universe, consisting of flashes of gamma rays that last from seconds to hours. There have been attempts to observe gamma ray bursts, for example, from population III stars of about 500 solar mass at high redshifts. Here we argue that collapse of such high mass stars does not lead to gamma ray burst as their core collapse temperatures are not sufficient to produce gamma rays, leading to GRBs.

C. Sivaram; Kenath Arun

2010-08-24

57

High beta capture and mirror confinement of laser produced plasmas  

Microsoft Academic Search

A dense, mirror confined, target plasma is produced by high power laser irradiation of a solid lithium hydride particle, electrically suspended in a vacuum at the center of an established minimum-B magnetic field. Following expansion in and capture by the magnetic field, this target plasma is irradiated by an energetic neutral hydrogen beam. Charge exchange collisions with energetic beam particles

A. F. Haught; D. H. Polk; W. J. Fader; R. G. Tomlinson; R. A. Jong; W. B. Ard; A. E. Mensing; T. L. Churchill; J. L. Stufflebeam; F. J. Bresnock

1976-01-01

58

Human high denisty apolipoprotein A-I-lysolecithin-lecithin and sphingomyelin complexes. A method for high yield recombinations to lipoprotein complexes of reproducible stoichiometry.  

PubMed

High denisty apolipoprotein A-1 (apoLp A-I) has been prepared in a chromatographically and immunochemically homogeneous form. This apoprotein forms trimeric and tetrameric aggregates in aqueous solutions at higher concentrations. ApoLp A-I has been recombined in almost quantitative yield in the presence of lysolecithin with phosphatidylcholine and sphingomyelin to particles of reproducible stoichiometry. Lysolecithin is not required for the interactions of lecithin and sphingomyelin with the apoprotein A-I or for the stability of these complexes. Dialysis removes most of the lysolecithin without the loss of lecithin and sphingomyelin. ApoLp A-I-lecithin particles have a molecular weight of 200 000 and contain 50 molecules lecithin and 25 of lysolecithin. ApoLp A-I-sphingomyelin complexes contain 50 sphingomyelin and 13 lysolecithin molecules. The former particles show up as discs of 100 A diameter, and the latter particles are 250 A in diameter. Their thickness was estimated as 25 A in the apoLp A-I lecithin and 60 A in the apoLp A-I-sphingomyelin particles. ApoLp A-I and lysolecithin form complexes whose densities depend on the lysolecithin concentration. Lysolecithin enhances the binding of phosphatidylcholine to apoLP A-I, yielding lipoprotein complexes with decreasing density. The yield of apoLp A-I-sphingomyelin-lysolecithin complexes is proportional to the lysolecithin concentration. The ratio of apoLp A-I to sphingomyelin in all these complexes remains constant. PMID:1254243

Stoffel, W; Därr, W

1976-02-01

59

Solvothermal-Assisted Exfoliation Process to Produce Graphene with High Yield and High Quality  

E-print Network

Solvothermal-Assisted Exfoliation Process to Produce Graphene with High Yield and High Quality Wen distinctive characteristics. Various methods have been developed to produce graphene, including mechanical [1-cost and is one of the favoured methods for producing graphene. Currently, three major carbon sources are used

Gao, Hongjun

60

Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Remote sensing of the upper tropospheric state of storms using space-borne high spectral resoluti...  

E-print Network

Reproduced with permission of the copyright owner. Further reproduction prohibited without of Wisconsin at Madison pg. n/a #12;Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #12;Reproduced with permission of the copyright owner. Further reproduction

Wisconsin at Madison, University of

61

Picking vanished proteins from the void: how to collect and ship/share extremely dilute proteins in a reproducible and highly efficient manner.  

PubMed

Successful proteome analyses of highly dilute samples are strongly dependent on optimized workflows considering especially sample preparation prior to highly sensitive mass spectrometric analysis. Various methods are available for enrichment of proteome samples, each characterized by specific advantages and disadvantages limiting their general application as a method of choice. Here we suggest an optimized universal protocol ensuring reproducibility and effective enrichment of dilute samples by commercial affinity beads. By comparably assessing the performance of the new protocol with selected standard enrichment techniques, we show the seamless application of the enrichment in common mass spectrometry based proteomic workflows. Further, novel applications are suggested including a facile storage and shipping of desiccated, trapped proteome samples at ambient temperatures and usage of the affinity beads for gel-free proteomic approaches. PMID:24987932

Bonn, Florian; Bartel, Jürgen; Büttner, Knut; Hecker, Michael; Otto, Andreas; Becher, Dörte

2014-08-01

62

Reproducibility of striatal and thalamic dopamine D2 receptor binding using [11C]raclopride with high-resolution positron emission tomography  

PubMed Central

Positron emission tomography (PET) imaging of small striatal brain structures such as the ventral striatum (VST) has been hampered by low spatial resolution causing partial-volume effects. The high-resolution research tomograph (HRRT) is a brain-dedicated PET scanner that has considerably better spatial resolution than its predecessors. However, its superior spatial resolution is associated with a lower signal-to-noise ratio. We evaluated the test–retest reliability of the striatal and thalamic dopamine D2 receptor binding using the HRRT scanner. Seven healthy male volunteers underwent two [11C]raclopride PET scans with a 2.5-hour interval. Dopamine D2 receptor availability was quantified as binding potential (BPND) using the simplified reference tissue model. To evaluate the reproducibility of repeated BPND estimations, absolute variability (VAR) and intraclass correlation coefficients (ICCs) were calculated. VAR values indicated fairly good reproducibility and were 3.6% to 4.5% for the caudate nucleus and putamen and 4.5% to 6.4% for the lateral and medial part of the thalamus. In the VST, the VAR value was 5.8% when the definition was made in the coronal plane. However, the ICC values were only moderate, in the range of 0.34 to 0.66, for all regions except the putamen (0.87). Experimental signal processing methods improved neither ICC nor VAR values significantly. PMID:20442726

Alakurtti, Kati; Aalto, Sargo; Johansson, Jarkko J; Nagren, Kjell; Tuokkola, Terhi; Oikonen, Vesa; Laine, Matti; Rinne, Juha O

2011-01-01

63

Method and apparatus for producing high purity silicon  

DOEpatents

A method for producing high purity silicon includes forming a copper silicide alloy and positioning the alloy within an enclosure. A filament member is also placed within the enclosure opposite the alloy. The enclosure is then filled with a chemical vapor transport gas adapted for transporting silicon. Finally, both the filament member and the alloy are heated to temperatures sufficient to cause the gas to react with silicon at the alloy surface and deposit the reacted silicon on the filament member. In addition, an apparatus for carrying out this method is also disclosed.

Olson, J.M.

1983-05-27

64

Chemical dimerization of crystalline anthracene produced by transient high pressure  

SciTech Connect

We report the production of a chemically bound dimer of anthracene produced by the shock compression of crystalline anthracene. The experimental probe used to detect the dimer structure was time-of-flight (TOF) mass spectrometry. The principal method used to produce the shock compression was the impact of electrically accelerated flyers ( slappers'') with the surface of the anthracene crystals. Our work correlates well with earlier experimental and theoretical work concerning chemical processes that can occur in pressurized anthracene and other aromatic materials. We briefly review the earlier work. The anthracene crystals were shocked to various pressures in the interval 9 to 22 GPa. Also various crystal thicknesses were employed; this allowed us to control the time interval over which various anthracene particles'' in the crystal were held at high pressure and temperature. At a pressure of [similar to]22.1 GPa we observe dimer formation in 20 ns or less. For a shock pressure of 9 GPa no dimer is produced, whereas for shock pressures of 18.4 GPa or higher dimer production is always observed. Under some conditions significant conversion of monomer to dimer is seen (up to a conversion of over 50%). A remarkably simple experimental observation is that the [ital only] new chemical species observed in the experiments at 18.4 GPa and higher is the dimer species. We present evidence that the dimerization is the result of a pressure-driven Diels--Alder reaction and that such reactions are characteristic of materials containing aromatic rings when they are shocked to high pressure.

Engelke, R.; Blais, N.C. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States))

1994-12-15

65

Reproducing in Cities  

Microsoft Academic Search

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

Ruth Mace

2008-01-01

66

Uniform metal nanoparticles produced at high yield in dense microemulsions.  

PubMed

This article demonstrates that bicontinuous microemulsions are optimal templates for high yield production of metal nanoparticles. We have verified this for a variety of microemulsion systems having AOT (sodium bis (2-ethyhexyl) sulphosuccinate) or a fluorocarbon (perfluoro (4-methyl-3,6-dioxaoctane)sulphonate) as surfactant mixed with water and oils like n-heptane or n-dodecane. Several types of metal nanoparticles, including platinum, gold and iron, were produced in these microemulsions having a size range spanning 1.8-17 nm with a very narrow size distribution of ±1 nm. Remarkably high mass concentrations up to 3% were reached. Size and concentration of the nanoparticles could be varied with the stoichiometries of the reagents that constituted them. The optimization towards high yield while maintaining low size polydispersity is due to the decoupling of the time scales for the precipitation reaction and for coarsening. In actual fact, coalescence is essentially prevented by the immobilization of nanoparticles within the bicontinuous microemulsion structure. PMID:22305574

Kowlgi, Krishna; Lafont, Ugo; Rappolt, Michael; Koper, Ger

2012-04-15

67

High- and low-temperature-stable thermite 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, Danny L. (Camden, OH); Mohler, Jonathan H. (Spring Valley, OH)

1990-10-16

68

Isolation of thermophilic L-lactic acid producing bacteria showing homo-fermentative manner under high aeration condition.  

PubMed

By applying non-sterile open fermentation of food waste, various thermotolerant l-lactic acid-producing bacteria were isolated and identified. The predominant bacterial isolates showing higher accumulation of l-lactic acid belong to 3 groups of Bacillus coagulans, according to their 16S rRNA gene sequence similarities. B. coagulans strains M21 and M36 produced high amounts of l-lactic acid of high optical purity and lactic acid selectivity in model kitchen refuse medium and glucose-yeast extract-peptone medium. Other thermotolerant isolates resembling to Bacillus humi, B. ruris, B. subtilis, B. niacini and B. soli were also identified. These bacteria produced low amounts of l-lactic acid of more than 99% optical purity. All isolated strains showed the highest growth rate at temperatures around 55-60°C. They showed unique responses to various oxygen supply conditions. The majority of isolates produced l-lactic acid at a low overall oxygen transfer coefficient (KLa); however, acetic acid was produced instead of l-lactic acid at a high KLa. B. coagulans M21 was the only strain that produced high, consistent, and reproducible amounts of optically pure l-lactic acid (>99% optical purity) under high and low KLa conditions in a homo-fermentative manner. PMID:24119530

Tongpim, Saowanit; Meidong, Ratchanu; Poudel, Pramod; Yoshino, Satoshi; Okugawa, Yuki; Tashiro, Yukihiro; Taniguchi, Masayuki; Sakai, Kenji

2014-03-01

69

Magnetogastrography (MGG) Reproducibility Assessments  

NASA Astrophysics Data System (ADS)

Seven healthy subjects underwent a magnetic pulse of 32 mT for 17 ms, seven times in 90 minutes. The procedure was repeated one and two weeks later. Assessments of the gastric emptying were carried out for each one of the measurements and a statistical analysis of ANOVA was performed for every group of data. The gastric emptying time was 19.22 ± 5 min. Reproducibility estimation was above 85%. Therefore, magnetogastrography seems to be an excellent technique to be implemented in routine clinical trials.

de la Roca-Chiapas, J. M.; Córdova, T.; Hernández, E.; Solorio, S.; Solís Ortiz, S.; Sosa, M.

2006-09-01

70

Quercetin nanosuspensions produced by high-pressure homogenization.  

PubMed

High-pressure homogenization (HPH) was used to increase the water solubility of quercetin crystals, which exhibit antioxidant, anti-inflammatory, and anticancer properties but poor water solubility and oral bioavailability. The improved water solubility of quercetin by HPH treatment could be attributed to very fine suspensions produced in the nanometric range (~400 nm) and loss of crystallinity caused by mechanical friction and stresses, which were verified by particle size measurements, differential scanning calorimetry (DSC), atomic force microscopy (AFM), and scanning electron microscopy (SEM) results. Easily water redispersible powders were fabricated by the combination of HPH treatment and spray-drying process when maltodextrin was used as a carrier agent. HPH-treated spray-dried powders exhibited higher antioxidant activities than nontreated samples through increased water dispersity in terms of radical scavenging activity, reducing ability, and oxygen radical absorbance capacity determinations. This study suggests that the combination of HPH treatment with spray-drying would be an excellent processing method for the development of quercetin-based functional food products. PMID:24471519

Karadag, Ayse; Ozcelik, Beraat; Huang, Qingrong

2014-02-26

71

Processes for producing low cost, high efficiency silicon solar cells  

DOEpatents

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime {tau} and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime {tau} and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO{sub x}. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure. 28 figs.

Rohatgi, A.; Doshi, P.; Tate, J.K.; Mejia, J.; Chen, Z.

1998-06-16

72

Processes for producing low cost, high efficiency silicon solar cells  

DOEpatents

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure.

Rohatgi, Ajeet (Marietta, GA); Doshi, Parag (Altanta, GA); Tate, John Keith (Lawrenceville, GA); Mejia, Jose (Atlanta, GA); Chen, Zhizhang (Duluth, GA)

1998-06-16

73

Processes for producing low cost, high efficiency silicon solar cells  

DOEpatents

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. Silicon solar cell efficiencies of 16.9% have been achieved. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x.

Rohatgi, Ajeet (Marietta, GA); Chen, Zhizhang (Duluth, GA); Doshi, Parag (Atlanta, GA)

1996-01-01

74

Green Synthesis of Large-Scale Highly Ordered Core@Shell Nanoporous Au@Ag Nanorod Arrays as Sensitive and Reproducible 3D SERS Substrates.  

PubMed

We present a simple green synthetic approach to large-scale and highly ordered arrays of vertical nanoporous Au nanorods, with an ultrathin Ag-layer in situ electrodeposited on each nanoporous Au nanorod (denoted as core@shell nanoporous Au@Ag nanorod). As both the nanopores within each nanorod and the gaps between the neighboring nanorods create three-dimensional (3D) "hot spots" homogeneously distributed throughout the whole substrate, the core@shell nanoporous Au@Ag nanorod arrays were proved to be sensitive and reproducible surface-enhanced Raman scattering (SERS) substrates. Not only universal probe molecules (rhodamine 6G, R6G) but also nonadsorbing molecules (polychlorinated biphenyls, PCBs) have been detected by using the substrates. After mono-6-thio-?-cyclodextrin (HS-?-CD) was modified to efficiently capture more PCBs molecules, the detection limit of PCBs was further reduced to 5.35 × 10(-7) M. As a trial of practical application, R6G and PCBs with different molar ratios in their mixed solutions were identified, and two congeners of PCBs in their mixture could also be distinguished, showing great potentials in real-time simultaneous detection of multiple pollutants. PMID:25162796

Chen, Bin; Meng, Guowen; Huang, Qing; Huang, Zhulin; Xu, Qiaoling; Zhu, Chuhong; Qian, Yiwu; Ding, Yi

2014-09-24

75

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. PMID:23899933

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

2013-01-01

76

An innovative stand-alone bioreactor for the highly reproducible transfer of cyclic mechanical stretch to stem cells cultured in a 3D scaffold.  

PubMed

Much evidence in the literature demonstrates the effect of cyclic mechanical stretch in maintaining, or addressing, a muscle phenotype. Such results were obtained using several technical approaches, useful for the experimental collection of proofs of principle but probably unsuitable for application in clinical regenerative medicine. Here we aimed to design a reliable innovative bioreactor, acting as a stand-alone cell culture incubator, easy to operate and effective in addressing mesenchymal stem cells (MSCs) seeded onto a 3D bioreabsorbable scaffold, towards a muscle phenotype via the transfer of a controlled and highly-reproducible cyclic deformation. Electron microscopy, immunohistochemistry and biochemical analysis of the obtained pseudotissue constructs showed that cells 'trained' over 1?week: (a) displayed multilayer organization and invaded the 3D mesh of the scaffold; and (b) expressed typical markers of muscle cells. This effect was due only to physical stimulation of the cells, without the need of any other chemical or genetic manipulation. This device is thus proposed as a prototypal instrument to obtain pseudotissue constructs to test in cardiovascular regenerative medicine, using good manufacturing procedures. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22865609

Govoni, Marco; Lotti, Fabrizio; Biagiotti, Luigi; Lannocca, Maurizio; Pasquinelli, Gianandrea; Valente, Sabrina; Muscari, Claudio; Bonafè, Francesca; Caldarera, Claudio M; Guarnieri, Carlo; Cavalcanti, Silvio; Giordano, Emanuele

2014-10-01

77

A light hydrocarbon fuel processor producing high-purity hydrogen  

NASA Astrophysics Data System (ADS)

This paper discusses the design process and presents performance data for a dual fuel (natural gas and LPG) fuel processor for PEM fuel cells delivering between 2 and 8 kW electric power in stationary applications. The fuel processor resulted from a series of design compromises made to address different design constraints. First, the product quality was selected; then, the unit operations needed to achieve that product quality were chosen from the pool of available technologies. Next, the specific equipment needed for each unit operation was selected. Finally, the unit operations were thermally integrated to achieve high thermal efficiency. Early in the design process, it was decided that the fuel processor would deliver high-purity hydrogen. Hydrogen can be separated from other gases by pressure-driven processes based on either selective adsorption or permeation. The pressure requirement made steam reforming (SR) the preferred reforming technology because it does not require compression of combustion air; therefore, steam reforming is more efficient in a high-pressure fuel processor than alternative technologies like autothermal reforming (ATR) or partial oxidation (POX), where the combustion occurs at the pressure of the process stream. A low-temperature pre-reformer reactor is needed upstream of a steam reformer to suppress coke formation; yet, low temperatures facilitate the formation of metal sulfides that deactivate the catalyst. For this reason, a desulfurization unit is needed upstream of the pre-reformer. Hydrogen separation was implemented using a palladium alloy membrane. Packed beds were chosen for the pre-reformer and reformer reactors primarily because of their low cost, relatively simple operation and low maintenance. Commercial, off-the-shelf balance of plant (BOP) components (pumps, valves, and heat exchangers) were used to integrate the unit operations. The fuel processor delivers up to 100 slm hydrogen >99.9% pure with <1 ppm CO, <3 ppm CO 2. The thermal efficiency is better than 67% operating at full load. This fuel processor has been integrated with a 5-kW fuel cell producing electricity and hot water.

Löffler, Daniel G.; Taylor, Kyle; Mason, Dylan

78

Chemical dimerization of crystalline anthracene produced by transient high pressure  

Microsoft Academic Search

We report the production of a chemically bound dimer of anthracene produced by the shock compression of crystalline anthracene. The experimental probe used to detect the dimer structure was time-of-flight (TOF) mass spectrometry. The principal method used to produce the shock compression was the impact of electrically accelerated flyers (‘‘slappers’’) with the surface of the anthracene crystals. Our work correlates

Ray Engelke; Normand C. Blais

1994-01-01

79

Highly reproducible large-area and double-sided pulsed laser deposition of HTSC YBCO:Ag thin films for microwave applications  

Microsoft Academic Search

Large-area pulsed laser deposition (PLD) producing high-quality YBa2Cu3O7-x (YBCO) thin films on both sides of R-plane sapphire substrates with CeO2 buffer layer is used routinely to optimize planar microwave stripline filters for satellite and mobile communication systems. A relatively simple PLD arrangement with fixed laser plume and rotating substrate, with an offset between the laser plume and the center of

M. Lorenz; H. Hochmuth; D. Natusch; K. Kreher

1999-01-01

80

Method for producing high surface area chromia materials for catalysis  

DOEpatents

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 glycol, DMSO, and dimethyl formamide. The synthesis involves the dissolution of the metal salt in a solvent followed by an addition of a proton scavenger, such as an epoxide, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively.

Gash, Alexander E. (Brentwood, CA); Satcher, Joe (Patterson, CA); Tillotson, Thomas (Tracy, CA); Hrubesh, Lawrence (Pleasanton, CA); Simpson, Randall (Livermore, CA)

2007-05-01

81

Towards reproducible, scalable lateral molecular electronic devices  

E-print Network

An approach to reproducibly fabricate molecular electronic devices is presented. Lateral nanometer-scale gaps with high yield are formed in Au/Pd nanowires by a combination of electromigration and Joule-heating-induced thermomechanical stress...

Durkan, Colm; Zhang, Qian

2014-08-26

82

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 and/or suspending 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); Mann, Nicholas R. (Blackfoot, ID); Todd, Terry A. (Aberdeen, ID); Herbst, Ronald S. (Idaho Falls, ID)

2010-10-05

83

Comparison of Methods of Producing Very Highly Stripped Uranium Beams.  

National Technical Information Service (NTIS)

A comparison is made between the production of high intensity beams of helium-like uranium ions, U exp 90+ , by conventional and exotic ion sources, and by the foil stripping of highly accelerated ions output from the Bevalac. The parameter requirements a...

I. G. Brown

1983-01-01

84

New process produces high-power Schottky diodes  

NASA Technical Reports Server (NTRS)

Processing procedure using low-temperature platinum silicide, results in successful high-yield fabrication of large-area mesa-geometry Schottky diodes, with reverse breakdown voltages as high as 150 volts and leak currents less than 5 milliamps at 212 F.

Cordes, L. F.; Garfinkel, M.; Taft, E. A.

1977-01-01

85

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

86

High Degree of Interlaboratory Reproducibility of Human Immunodeficiency Virus Type 1 Protease and Reverse Transcriptase Sequencing of Plasma Samples from Heavily Treated Patients  

Microsoft Academic Search

We assessed the reproducibility of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) and protease sequencing using cryopreserved plasma aliquots obtained from 46 heavily treated HIV-1-infected individuals in two laboratories using dideoxynucleotide sequencing. The rates of complete sequence concor- dance between the two laboratories were 99.1% for the protease sequence and 99.0% for the RT sequence. Approximately 90% of

ROBERT W. SHAFER; KURT HERTOGS; ANDREW R. ZOLOPA; ANN WARFORD; STUART BLOOR; BRADLEY J. BETTS; THOMAS C. MERIGAN; RICHARD HARRIGAN; BRENDON A. LARDER

87

Viscoelastic Relaxation of Topographic Highs on Venus to Produce Coronae  

NASA Technical Reports Server (NTRS)

Coronae on Venus are believed to result from the gravitationally driven relaxation of topography that was originally raised by mantle diapirs. We examine this relaxation using a viscoelastic finite element code, and show that an initially plateau shaped load will evolve to the characteristic corona topography of central raised bowl, annular rim, and surrounding moat. Stresses induced by the relaxation are consistent with the development of concentric extensional fracturing common on the outer margins of corona moats. However, relaxation is not expected to produce the concentric faulting often observed on the annular rim. The relaxation timescale is shorter than the diapir cooling timescale, so loss of thermal support controls the rate at which topography is reduced. The final corona shape is supported by buoyancy and flexural stresses and will persist through geologic time. Development of lower, flatter central bowls and narrower and more pronounced annular rims and moats enhanced by thicker crusts, higher thermal gradients, and crustal thinning over the diapir.

Janes, Daniel M.; Squyres, Steven W.

1995-01-01

88

Solvothermal-assisted exfoliation process to produce graphene with high yield and high quality  

Microsoft Academic Search

Monolayer and bilayer graphene sheets have been produced by a solvothermal-assisted exfoliation process in a highly polar\\u000a organic solvent, acetonitrile, using expanded graphite (EG) as the starting material. It is proposed that the dipole-induced\\u000a dipole interactions between graphene and acetonitrile facilitate the exfoliation and dispersion of graphene. The facile and\\u000a effective solvothermal-assisted exfoliation process raises the low yield of graphene

Wen Qian; Rui Hao; Yanglong Hou; Yuan Tian; Chengmin Shen; Hongjun Gao; Xuelei Liang

2009-01-01

89

Simulation of neutrons produced by high-energy muons underground  

E-print Network

This article describes the Monte Carlo simulation used to interpret the measurement of the muon-induced neutron flux in the Boulby Underground Laboratory (North Yorkshire, UK), recently performed using a large scintillator veto deployed around the ZEPLIN-II WIMP detector. Version 8.2 of the GEANT4 toolkit was used after relevant benchmarking and validation of neutron production models. In the direct comparison between Monte Carlo and experimental data, we find that the simulation produces a 1.8 times higher neutron rate, which we interpret as over-production in lead by GEANT4. The dominance of this material in neutron production allows us to estimate the absolute neutron yield in lead as (1.31 +/- 0.06) x 10^(-3) neutrons/muon/(g/cm^2) for a mean muon energy of 260 GeV. Simulated nuclear recoils due to muon-induced neutrons in the ZEPLIN-II target volume (~1 year exposure) showed that, although a small rate of events is expected from this source of background in the energy range of interest for dark matter searches, no event survives an anti-coincidence cut with the veto.

A. Lindote; H. M. Araujo; V. A. Kudryavtsev; M. Robinson

2008-10-09

90

Reproducing kernel element method Part III: Generalized enrichment and applications  

E-print Network

Reproducing kernel element method Part III: Generalized enrichment and applications Hongsheng Lu finite element methods, the construction proposed here has more flexibility and only needs minimal degrees of freedom. The optimal element with high reproducing capacity and overall minimal degrees

Li, Shaofan

91

High-Calorific Gas Mixtures Produced from Biomass  

NASA Astrophysics Data System (ADS)

Investigations in the field of processing of different types of biomass into high calorific gas fuel are carried out in the Joint Institute for High Temperatures of RAS. Design of technology for effective processing of low-grade solid fuel to gas mixtures which can be used as fuel for power plants is rather actual problem both in the view of natural resources conservation and in the view of the development of autonomous energy unit for thermal and electric power supply. The experimental data on quantity and composition of the gaseous products formed in the process of peat pyrolysis are presented at various operating parameters of the process. It is shown that as a result of peat pyrolysis and the subsequent cracking of emanating products at temperature 1,000 °C it is possible to receive 1.4 m3 of gas with specific caloricity 11.7 MJ/m3 per 1 kg of original raw material.

Kosov, Valentin; Kosov, Vladimir; Sinelschikov, Vladimir; Zaichenko, Victor

92

Experimental challenges to reproduce seismic fault motion  

NASA Astrophysics Data System (ADS)

This presentation briefly reviews scientific and technical development in the studies of intermediate to high-velocity frictional properties of faults and summarizes remaining technical challenges to reproduce nucleation to growth processes of large earthquakes in laboratory. Nearly 10 high-velocity or low to high-velocity friction apparatuses have been built in the last several years in the world and it has become possible now to produce sub-plate velocity to seismic slip rate in a single machine. Despite spreading of high-velocity friction studies, reproducing seismic fault motion at high P and T conditions to cover the entire seismogenic zone is still a big challenge. Previous studies focused on (1) frictional melting, (2) thermal pressurization, and (3) high-velocity gouge behavior without frictional melting. Frictional melting process was solved as a Stefan problem with very good agreement with experimental results. Thermal pressurization has been solved theoretically based on measured transport properties and has been included successfully in the modeling of earthquake generation. High-velocity gouge experiments in the last several years have revealed that a wide variety of gouges exhibit dramatic weakening at high velocities (e.g., Di Toro et al., 2011, Nature). Most gouge experiments were done under dry conditions partly to separate gouge friction from the involvement of thermal pressurization. However, recent studies demonstrated that dehydration or degassing due to mineral decomposition can occur during seismic fault motion. Those results not only provided a new view of looking at natural fault zones in search of geological evidence of seismic fault motion, but also indicated that thermal pressurization and gouge weakening can occur simultaneously even in initially dry gouge. Thus experiments with controlled pore pressure are needed. I have struggled to make a pressure vessel for wet high-velocity experiments in the last several years. A technical difficulty was how to absorb hydrodynamic shock due to abrupt fault motion in the vessel, and this was overcome by pressurizing water in the vessel, acting as pore fluid, using pressurized gas (in other words using gas as a cushion). I will report preliminary experimental results on high-velocity rock-on-rock friction under pore-water pressure. Other technical challenges are (i) how to produce step-change in velocity to see if the framework of rate-and-state friction law holds in high-velocity regime, (ii) how to conduct high-velocity friction experiments in hydrothermal conditions to study frictional properties relevant to slow slip and low-frequency tremors, and (iii) how to conduct high-velocity friction experiments at high normal stresses. The first task became possible with a low to high-velocity apparatus in Beijing and a few other machines, and I will show some preliminary results. There is no fundamental difficulty in (ii) since O-ring is enough to seal piston rotating at a high speed. However, (iii) will be the hardest because of severe thermal fracturing of host rocks that limits the axial stress. Use of aluminum sleeve made it possible to apply the normal stress to about 30 MPa, but new device and a high motor power is needed to go higher normal stress.

Shimamoto, T.

2011-12-01

93

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

94

Cheap imports next ordeal for Europe's high-cost producers  

SciTech Connect

About one-third of Europe's 34 cracker and downstream units lost money in the final quarter of 1992, says Chem Systems (London). Average return on capital employed is negative - at the same level as in the gloomy days of the early 1980s - yet average operating rates are 80% now, compared with 65% a decade ago. Margins at what Chem Systems calls leader cracks (naphtha-based units that use good modern practices) are DM42/m.t. ethylene, DM100/m.t. less than they were in 1991. The consultant firm's recent report, European Petrochemical Strategy in the 1990s, suggests closure of 5%-10% of high-cost production. But, Chem Systems director Roger Longley states: We are not advocating wholesale closure. There are a small number (of plants) where additional investment would not payback that would be economical to shut. Cost reduction through mergers and acquisitions and operational changes is much more important, especially from an international aspect, Longley says. One thing people do not fully appreciate is that Europe is a high-cost region for petrochemical production, he adds. Traditionally, Europe exports 5% of its ethylene output, now it needs to tolerate cheap imports.

Chynoweth, E.

1993-02-03

95

Process for producing a high emittance coating and resulting article  

NASA Technical Reports Server (NTRS)

Process for anodizing aluminum or its alloys to obtain a surface particularly having high infrared emittance by anodizing an aluminum or aluminum alloy substrate surface in an aqueous sulfuric acid solution at elevated temperature and by a step-wise current density procedure, followed by sealing the resulting anodized surface. In a preferred embodiment the aluminum or aluminum alloy substrate is first alkaline cleaned and then chemically brightened in an acid bath The resulting cleaned substrate is anodized in a 15% by weight sulfuric acid bath maintained at a temperature of 30.degree. C. Anodizing is carried out by a step-wise current density procedure at 19 amperes per square ft. (ASF) for 20 minutes, 15 ASF for 20 minutes and 10 ASF for 20 minutes. After anodizing the sample is sealed by immersion in water at 200.degree. F. and then air dried. The resulting coating has a high infrared emissivity of about 0.92 and a solar absorptivity of about 0.2, for a 5657 aluminum alloy, and a relatively thick anodic coating of about 1 mil.

Le, Huong G. (Inventor); O'Brien, Dudley L. (Inventor)

1993-01-01

96

High quality optically polished aluminum mirror and process for producing  

NASA Technical Reports Server (NTRS)

A new technical advancement in the field of precision aluminum optics permits high quality optical polishing of aluminum monolith, which, in the field of optics, offers numerous benefits because of its machinability, lightweight, and low cost. This invention combines diamond turning and conventional polishing along with india ink, a newly adopted material, for the polishing to accomplish a significant improvement in surface precision of aluminum monolith for optical purposes. This invention guarantees the precise optical polishing of typical bare aluminum monolith to surface roughness of less than about 30 angstroms rms and preferably about 5 angstroms rms while maintaining a surface figure accuracy in terms of surface figure error of not more than one-fifteenth of wave peak-to-valley.

Lyons, III, James J. (Inventor); Zaniewski, John J. (Inventor)

2005-01-01

97

High-Frequency Stimulation Produces a Transient Blockade of Voltage-Gated Currents in Subthalamic Neurons  

E-print Network

tetanus, consist- ing of 100- s bipolar stimuli at a frequency of 100­250 Hz during 1 min, produced a full. Thus a high-frequency tetanus produces a blockade of the spontaneous activities of STN neurons

Cossart, Rosa

98

High flux of relativistic electrons produced in femtosecond laser-thin foil target interactions: Characterization with nuclear techniques  

SciTech Connect

We present a protocol to characterize the high energy electron beam emitted in the interaction of an ultraintense laser with matter at intensities higher than 10{sup 19} W cm{sup -2}. The electron energies and angular distributions are determined as well as the total number of electrons produced above a 10 MeV threshold. This protocol is based on measurements with an electron spectrometer and nuclear activation techniques, combined with Monte Carlo simulations based on the GEANT3 code. The method is detailed and exemplified with data obtained with polypropylene and copper thin solid targets at a laser intensity of 2x10{sup 19} W cm{sup -2}. Special care is taken of the different sources of uncertainties. In particular, the reproducibility of the laser shots is considered.

Gerbaux, M.; Gobet, F.; Aleonard, M. M.; Hannachi, F.; Malka, G.; Scheurer, J. N.; Tarisien, M.; Claverie, G. [Universite Bordeaux 1, CNRS-IN2P3, Centre d'Etudes Nucleaires de Bordeaux Gradignan, Chemin du Solarium, 33175 Gradignan (France); Meot, V.; Morel, P. [CEA/DAM Ile de France, DPTA/Service de Physique Nucleaire, BP12, 91680 Bruyeres-le-Chatel (France); Faure, J.; Glinec, Y.; Guemnie-Tafo, A.; Malka, V.; Manclossi, M.; Santos, J. J. [Laboratoire d'Optique Appliquee, ENSTA-Ecole Polytechnique, Chemin de la Huniere, 91761 Palaiseau Cedex (France)

2008-02-15

99

Combined experimental and numerical approach to evaluate impact scaling relations and reproducibility of craters produced at the Experimental Projectile Impact Chamber (E.P.I.C., Centro de Astrobiología, Spain.)  

NASA Astrophysics Data System (ADS)

The Experimental Projectile Impact Chamber at Centro de Astrobiología, Spain, consists of a 7m wide, funnel-shaped test bed, and a 20.5mm caliber compressed N2 gas gun. The test bed can be filled with any type of target material, but is especially designed for wet target experiments. The shape and size aim to decrease disturbance from reflected surface waves in wet target experiments. Experiments are done under 1Atm pressure. The gas gun can launch projectiles of any material and dimensions <20mm (smaller diameters using sabots), and at any angle from vertical to near horizontal. The projectile velocities are of the order of a few hundreds of meters per second depending mainly on the gas pressure, as well as projectile diameter and density. When using a dry sand target a transient crater about 30cm wide is produced. Wet target experiments have not yet been performed in this newly installed test chamber, but transient cavities in water are expected to be in the order of 50-70cm wide. The large scale allows for detailed study of the dynamics of cratering motions during the stages of crater growth and subsequent collapse, especially in wet targets. These observations provide valuable benchmark data for numerical simulations and for comparison with field studies. Here we describe the results of ten impact experiments using three different gas pressures (100bar, 180bar, 200bar), two projectile compositions (20mm, 5.7g delrin; 20mm, 16.3g Al2O3), and two different impact angles (90? and 53? over the horizontal plane). Nine of the experiments were done in a quarter-space geometry using a specially designed camera tank with a 45mm thick glass window. One experiment was done in half-space geometry as reference. The experiments were recorded with a high-speed digital video camera, and the resulting craters were documented with a digital still frame camera. Projectile velocities are estimated with a combination of tracking software and a Shooting Chrony Alpha M-1 chronograph to be about 330m/s for delrin (100bar), 220m/s for Al2O3 (100bar), 400m/s for delrin (200bar), and 275m/s for Al2O3 (200bar). The velocities for the lighter delrin projectile and at the higher pressure are above the speed of sound in dry silica sand (243 m/s; Sandia report SAND2007-3524). The experimental set up (i.e. target material, projectile density and velocity, impact angle), as well as the dimensions of the resulting craters, are used as inputs in numerical simulation using the iSALE computational code. Results from these simulations will be presented and compared with the experiments.

Ormö, J.; Wünnemann, K.; Collins, G.; Melero Asensio, I.

2012-04-01

100

Evaluation of Land Surface Models in Reproducing Satellite Derived Leaf Area Index over the High-Latitude Northern Hemisphere. Part II: Earth System Models  

E-print Network

Abstract: Leaf Area Index (LAI) is a key parameter in the Earth System Models (ESMs) since it strongly affects land-surface boundary conditions and the exchange of matter and energy with the atmosphere. Observations and data products derived from satellite remote sensing are important for the validation and evaluation of ESMs from regional to global scales. Several decades ’ worth of satellite data products are now available at global scale which represents a unique opportunity to contrast observations against model results. The objective of this study is to assess whether ESMs correctly reproduce the spatial variability of LAI when compared with satellite data and to compare the length of the growing season in the different models with the satellite data. To achieve this goal we analyse outputs from 11 coupled carbon-climate models that are based on the set of new global model simulations planned in support of the IPCC Fifth Assessment Report. We focus on the average LAI and the length of the growing season on Northern Hemisphere over the period 1986–2005. Additionally we compare the results with previous analyses (Part I) of

Ro Anav; Guillermo Murray-tortarolo; Pierre Friedlingstein; Stephen Sitch; Shilong Piao; Zaichun Zhu

2013-01-01

101

CONTROLLED LOW-STRENGTH MATERIAL (CLSM) PRODUCED WITH HIGH-LIME FLY ASH  

E-print Network

CONTROLLED LOW-STRENGTH MATERIAL (CLSM) PRODUCED WITH HIGH-LIME FLY ASH By Tarun R. Naik Director, Milwaukee, WI 53201 For presentation at the International Conference on the Utilization of Fly Ash and Other (CLSM) PRODUCED WITH HIGH-LIME FLY ASH Tarun R. Naik,* Bruce W. Ramme** and Henry J. Kolbeck** Abstract

Wisconsin-Milwaukee, University of

102

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

103

Oxygen-sensitive phosphorescent nanomaterials produced from high-density polyethylene films by local solvent-crazing.  

PubMed

Discrete solid-state phosphorescent oxygen sensors produced by local solvent-crazing of high density polyethylene films are described. The simple spotting of dye solution followed by tensile drawing of the polymer substrate provides uniform nanostructures with good spatial control, effective encapsulation of dye molecules, and quenchability by O2. The dye-polymer composite sensors prepared using toluene as a solvent and stabilized by annealing at high temperature, show moderate optical signals, near-optimal sensitivity to O2 (RSD at 21 KPa 1.9%), and reproducible phosphorescence lifetime readings. Calibration experiments performed over 0-25 kPa O2 and 10-30 °C temperatures ranges reveal linear Stern-Volmer plots and temperature dependences and minimal effect of humidity on sensor calibration. The high degree of lateral and in-depth homogeneity of these O2-sensitive materials was confirmed by high-resolution atomic force and wide-field optical microscopy, including 2D and 3D phosphorescence lifetime imaging. PMID:24422456

Toncelli, Claudio; Arzhakova, Olga V; Dolgova, Alla; Volynskii, Aleksandr L; Bakeev, Nikolai F; Kerry, Joe P; Papkovsky, Dmitri B

2014-02-01

104

Alfalfa is capable of producing high yields of high quality forage for hay, haylage, and pasture. However,  

E-print Network

Alfalfa is capable of producing high yields of high quality forage for hay, haylage, and pasture are appropriate. Alfalfa requires deep, well-drained soils with a pH >6.5 and high levels of phosphorus (P percent higher. The variety trials are managed at high fertility levels. Phosphorus and potassium were

Liskiewicz, Maciej

105

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

E-print Network

-producing algae of interest in 2nd generation biofuels. By conducting 96 experiments in parallel, photoirradianceOptical microplates for high-throughput screening of photosynthesis in lipid- producing algae the study of photosynthesis in algae. Societal challenges in energy sustainability have renewed interest

Basu, Amar S.

106

High tensile modulus of carbon nanotube nano-fibers produced by dielectrophoresis Han Zhang a  

E-print Network

High tensile modulus of carbon nanotube nano-fibers produced by dielectrophoresis Han Zhang a , Jie nano-fibers produced by dielectrophoresis. The average tensile modulus of the SWNT nano-fibers is 265, respectively, from a SWNT bundle of 10 nm diameter and a SWNT nano- fiber of diameter 55 nm with a packing

Qin, Lu-Chang

107

High-bone-mass-producing mutations in the Wnt signaling pathway result in distinct skeletal phenotypes  

E-print Network

High-bone-mass-producing mutations in the Wnt signaling pathway result in distinct skeletal Available online xxxx Edited by: Robert Recker Keywords: Wnt High bone mass Lrp5 Sclerostin Sost Mutations skeletal phenotypes, ranging from severe osteoporosis to severe osteosclerosis. Many high-bone- mass (HBM

108

Dielectric-Lined Multiwave Cerenkov Generators Producing High Power Millimeter Waves  

Microsoft Academic Search

This paper presents the concept of a Dielectric-lined Multiwave Cerenkov Generator(DMWCG) producing high power millimeter waves, which is investigated with a two and one half dimensional(\\u000a

Ting Shu; Yonggui Liu

1999-01-01

109

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

NASA Astrophysics Data System (ADS)

We consider the results of an experimental investigation of the temporal evolution of plasmas produced by high power laser irradiation of various materials. The experiment was done at the LULI Laboratory (Ecole Polytechnique, Paris). A comparative analysis is presented.

Aliverdiev, A.; Batani, D.; Malka, V.; Vinci, T.; Koenig, M.; Benuzzi-Mounaix, A.; Dezulian, R.

2006-04-01

110

Well-organized raspberry-like Ag@Cu bimetal nanoparticles for highly reliable and reproducible surface-enhanced Raman scattering  

NASA Astrophysics Data System (ADS)

Surface-enhanced Raman scattering (SERS) is ideally suited for probing and mapping surface species and incipient phases on fuel cell electrodes because of its high sensitivity and surface-selectivity, potentially offering insights into the mechanisms of chemical and energy transformation processes. In particular, bimetal nanostructures of coinage metals (Au, Ag, and Cu) have attracted much attention as SERS-active agents due to their distinctive electromagnetic field enhancements originated from surface plasmon resonance. Here we report excellent SERS-active, raspberry-like nanostructures composed of a silver (Ag) nanoparticle core decorated with smaller copper (Cu) nanoparticles, which displayed enhanced and broadened UV-Vis absorption spectra. These unique Ag@Cu raspberry nanostructures enable us to use blue, green, and red light as the excitation laser source for surface-enhanced Raman spectroscopy (SERS) with a large enhancement factor (EF). A highly reliable SERS effect was demonstrated using Rhodamine 6G (R6G) molecules and a thin film of gadolinium doped ceria.Surface-enhanced Raman scattering (SERS) is ideally suited for probing and mapping surface species and incipient phases on fuel cell electrodes because of its high sensitivity and surface-selectivity, potentially offering insights into the mechanisms of chemical and energy transformation processes. In particular, bimetal nanostructures of coinage metals (Au, Ag, and Cu) have attracted much attention as SERS-active agents due to their distinctive electromagnetic field enhancements originated from surface plasmon resonance. Here we report excellent SERS-active, raspberry-like nanostructures composed of a silver (Ag) nanoparticle core decorated with smaller copper (Cu) nanoparticles, which displayed enhanced and broadened UV-Vis absorption spectra. These unique Ag@Cu raspberry nanostructures enable us to use blue, green, and red light as the excitation laser source for surface-enhanced Raman spectroscopy (SERS) with a large enhancement factor (EF). A highly reliable SERS effect was demonstrated using Rhodamine 6G (R6G) molecules and a thin film of gadolinium doped ceria. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03363e

Lee, Jung-Pil; Chen, Dongchang; Li, Xiaxi; Yoo, Seungmin; Bottomley, Lawrence A.; El-Sayed, Mostafa A.; Park, Soojin; Liu, Meilin

2013-11-01

111

High-performance thin-film transistors produced from highly separated solution-processed carbon nanotubes  

NASA Astrophysics Data System (ADS)

Transistors utilizing carbon nanotube (CNT) thin films have exhibited high on-currents and mobilites greater than those of alternative channel materials. One critical problem that has limited the utilization of CNT thin-film transistors (TFTs) is the occurrence of unavoidable parasitic current paths stemming from metallic nanotubes. In this work, we experimentally demonstrate high-yield, high-performance TFTs composed of a highly purified single-walled carbon nanotube (SWNT) network. A solution process for a highly separated 99.9% semiconducting SWNT solution is used to acquire a significant enhancement in transistor performance, such as a high on/off ratio, high mobility, and high yields close to 100%.

Lee, Dongil; Seol, Myeong-Lok; Moon, Dong-Il; Bennett, Patrick; Yoder, Nathan; Humes, Jefford; Bokor, Jeffrey; Choi, Yang-Kyu; Choi, Sung-Jin

2014-04-01

112

ITK: enabling reproducible research and open science  

PubMed Central

Reproducibility verification is essential to the practice of the scientific method. Researchers report their findings, which are strengthened as other independent groups in the scientific community share similar outcomes. In the many scientific fields where software has become a fundamental tool for capturing and analyzing data, this requirement of reproducibility implies that reliable and comprehensive software platforms and tools should be made available to the scientific community. The tools will empower them and the public to verify, through practice, the reproducibility of observations that are reported in the scientific literature. Medical image analysis is one of the fields in which the use of computational resources, both software and hardware, are an essential platform for performing experimental work. In this arena, the introduction of the Insight Toolkit (ITK) in 1999 has transformed the field and facilitates its progress by accelerating the rate at which algorithmic implementations are developed, tested, disseminated and improved. By building on the efficiency and quality of open source methodologies, ITK has provided the medical image community with an effective platform on which to build a daily workflow that incorporates the true scientific practices of reproducibility verification. This article describes the multiple tools, methodologies, and practices that the ITK community has adopted, refined, and followed during the past decade, in order to become one of the research communities with the most modern reproducibility verification infrastructure. For example, 207 contributors have created over 2400 unit tests that provide over 84% code line test coverage. The Insight Journal, an open publication journal associated with the toolkit, has seen over 360,000 publication downloads. The median normalized closeness centrality, a measure of knowledge flow, resulting from the distributed peer code review system was high, 0.46. PMID:24600387

McCormick, Matthew; Liu, Xiaoxiao; Jomier, Julien; Marion, Charles; Ibanez, Luis

2014-01-01

113

Reproducibility of Functional Connectivity and Graph Measures Based on the Phase Lag Index (PLI) and Weighted Phase Lag Index (wPLI) Derived from High Resolution EEG  

PubMed Central

Functional connectivity (FC) and graph measures provide powerful means to analyze complex networks. The current study determines the inter-subject-variability using the coefficient of variation (CoV) and long-term test-retest-reliability (TRT) using the intra-class correlation coefficient (ICC) in 44 healthy subjects with 35 having a follow-up at years 1 and 2. FC was estimated from 256-channel-EEG by the phase-lag-index (PLI) and weighted PLI (wPLI) during an eyes-closed resting state condition. PLI quantifies the asymmetry of the distribution of instantaneous phase differences of two time-series and signifies, whether a consistent non-zero phase lag exists. WPLI extends the PLI by additionally accounting for the magnitude of the phase difference. Signal-space global and regional PLI/wPLI and weighted first-order graph measures, i.e. normalized clustering coefficient (gamma), normalized average path length (lambda), and the small-world-index (SWI) were calculated for theta-, alpha1-, alpha2- and beta-frequency bands. Inter-subject variability of global PLI was low to moderate over frequency bands (0.12high-resolution EEG has apparently good reliability, which is one important requirement for longitudinal studies exploring the effects of chronic brain diseases over several years. PMID:25286380

Hardmeier, Martin; Hatz, Florian; Bousleiman, Habib; Schindler, Christian; Stam, Cornelis Jan; Fuhr, Peter

2014-01-01

114

Utilizing high resolution and reconfigurable patterns in combination with inkjet printing to produce high performance circuits  

NASA Astrophysics Data System (ADS)

Inkjet printing on pre-fabricated high-resolution substrate is developed to improve the operational speed of printed organic transistors. The high-resolution features are designed to define transistor critical dimensions, while maintaining the flexibility to incorporate different circuit constructions. Logic gate and ring oscillator circuits fabricated by inkjet printing on the high-resolution substrate are demonstrated, to show that the same high resolution pattern can be adapted for constructing different electronic circuits.

Mei, P.; Ng, T. N.; Lujan, R. A.; Schwartz, D. E.; Kor, S.; Krusor, B. S.; Veres, J.

2014-09-01

115

Selection of high rosmarinic acid producing Lavandula vera MM cell lines  

Microsoft Academic Search

Selection of stable Lavandula vera MM cell lines producing high amounts of rosmarinic acid (RA) was performed using m-F-d,l-phenylalanine and p-F-d,l-phenylalanine. As a result, two callus lines L. vera MF and L. vera PF were obtained, which produced 1.95 and 1.71 times more rosmarinic acid in comparison with the parent culture. After adaptation of the selected callus lines in liquid

M. Georgiev; A. Pavlov; M. Ilieva

2006-01-01

116

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

117

High-energy ions produced in explosions of superheated atomic clusters  

Microsoft Academic Search

Efficient conversion of electromagnetic energy to particle energy is of fundamental importance in many areas of physics. A promising avenue for producing matter with unprecedented energy densities is by heating atomic clusters, an intermediate form of matter between molecules and solids1, with high-intensity, ultra-short light pulses2-4. Studies of noble-gas clusters heated with high-intensity (>1016Wcm-2) laser pulses indicate that a highly

T. Ditmire; J. W. G. Tisch; E. Springate; M. B. Mason; N. Hay; R. A. Smith; J. Marangos; M. H. R. Hutchinson

1997-01-01

118

Reproducibility of 3D chromatin configuration reconstructions.  

PubMed

It is widely recognized that the three-dimensional (3D) architecture of eukaryotic chromatin plays an important role in processes such as gene regulation and cancer-driving gene fusions. Observing or inferring this 3D structure at even modest resolutions had been problematic, since genomes are highly condensed and traditional assays are coarse. However, recently devised high-throughput molecular techniques have changed this situation. Notably, the development of a suite of chromatin conformation capture (CCC) assays has enabled elicitation of contacts-spatially close chromosomal loci-which have provided insights into chromatin architecture. Most analysis of CCC data has focused on the contact level, with less effort directed toward obtaining 3D reconstructions and evaluating the accuracy and reproducibility thereof. While questions of accuracy must be addressed experimentally, questions of reproducibility can be addressed statistically-the purpose of this paper. We use a constrained optimization technique to reconstruct chromatin configurations for a number of closely related yeast datasets and assess reproducibility using four metrics that measure the distance between 3D configurations. The first of these, Procrustes fitting, measures configuration closeness after applying reflection, rotation, translation, and scaling-based alignment of the structures. The others base comparisons on the within-configuration inter-point distance matrix. Inferential results for these metrics rely on suitable permutation approaches. Results indicate that distance matrix-based approaches are preferable to Procrustes analysis, not because of the metrics per se but rather on account of the ability to customize permutation schemes to handle within-chromosome contiguity. It has recently been emphasized that the use of constrained optimization approaches to 3D architecture reconstruction are prone to being trapped in local minima. Our methods of reproducibility assessment provide a means for comparing 3D reconstruction solutions so that we can discern between local and global optima by contrasting solutions under perturbed inputs. PMID:24519450

Segal, Mark R; Xiong, Hao; Capurso, Daniel; Vazquez, Mariel; Arsuaga, Javier

2014-07-01

119

Assessment of high and low enterotoxin A producing Staphylococcus aureus strains on pork sausage.  

PubMed

Three Staphylococcus aureus strains representing different alleles of the Siphoviridae prophage-encoded enterotoxin A (SEA) gene, including two high-SEA-producing strains and one low-SEA-producing strain were studied to investigate sea expression and SEA formation on a frankfurter type of sausage. The effect of lactic acid, an antimicrobial compound used as a preservative in food, was also investigated on the same product. All three strains were grown on pork sausages at 15°C for 14days in the presence or absence of lactic acid (1 or 2% v/v). Growth, sea mRNA expression and SEA formation were regularly monitored and compared between non-treated and treated sausages. For all experiments performed, the extracellular SEA formation significantly differed between the high- and low-SEA-producing strains, although growth and viability were overall the same. For the low producer (Sa51), the accumulated amount of extracellular SEA formed after 14days was close to the detection limit (less than 1ng/g) in all conditions; while Sa21 and Sa17, the two high-producing strains, formed 250±25.37ng/g and 750±82.65ng/g in non-treated sausage and 150±75.75ng/g and 300±83.89ng/g when treated with 1% lactic acid, respectively, after 14days. Sausages treated with 2% lactic acid followed the same pattern as above, but with an extended lag phase to 4days and reduced levels of enterotoxin formed for all strains. The difference in the level of SEA between the two high-producing strains is most likely due to the different clonal lineages of the sea-encoded Siphoviridae phages where induction of the prophage potentially could be the reason for higher production of SEA in one of the lines. Furthermore, a prolonged expression of sea gene in the two high-producing strains was observed during the entire incubation period, while the sea expression was under the detection limit in the low-producing strain. This study indicates that the high-SEA-producing strains, especially the strains with the putative capacity of prophage induction, could be more relevant in food safety aspects than low-producing type of strains on pork sausage. PMID:24859189

Zeaki, Nikoleta; Cao, Rong; Skandamis, Panagiotis N; Rådström, Peter; Schelin, Jenny

2014-07-16

120

A visual method for direct selection of high-producing Pichia pastoris clones  

PubMed Central

Background The methylotrophic yeast, Pichia pastoris, offers the possibility to generate a high amount of recombinant proteins in a fast and easy way to use expression system. Being a single-celled microorganism, P. pastoris is easy to manipulate and grows rapidly on inexpensive media at high cell densities. A simple and direct method for the selection of high-producing clones can dramatically enhance the whole production process along with significant decrease in production costs. Results A visual method for rapid selection of high-producing clones based on mannanase reporter system was developed. The study explained that it was possible to use mannanase activity as a measure of the expression level of the protein of interest. High-producing target protein clones were directly selected based on the size of hydrolysis holes in the selected plate. As an example, the target gene (9elp-hal18) was expressed and purified in Pichia pastoris using this technology. Conclusions A novel methodology is proposed for obtaining the high-producing clones of proteins of interest, based on the mannanase reporter system. This system may be adapted to other microorganisms, such as Saccharomyces cerevisiae for the selection of clones. PMID:21418613

2011-01-01

121

Reproducing kernel element method. Part IV: Globally compatible Cn  

E-print Network

Reproducing kernel element method. Part IV: Globally compatible Cn ðn P 1� triangular hierarchy Cn ðX� triangular element hierarchy is constructed in the framework of reproducing kernel element conforming element can be made arbitrarily high ðn P 1�. The triangle interpolation field can interpolate

Li, Shaofan

122

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

123

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

124

Vitra-violet process for producing flame resistant polyamides and products produced thereby. [protective clothing for high oxygen environments  

NASA Technical Reports Server (NTRS)

Aromatic polyamides with improved nonflammability characteristics are produced by contacting a polyamide substrate with a gaseous medium comprising a minor amount of a haloolefinic material and an inert diluent in the presence of light having sufficient energy to effect chemical addition of the haloolefin to the polyamide substrate.

Toy, M. S.; Stringham, R. S. (inventors)

1980-01-01

125

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

126

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

127

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 (ca. 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. 10 figs.

Bianco, R.; Buckman, R.W. Jr.; Geller, C.B.

1999-02-09

128

Reproducibility of Magnetic Resonance Perfusion Imaging  

PubMed Central

Dynamic MR biomarkers (T2*-weighted or susceptibility-based and T1-weighted or relaxivity-enhanced) have been applied to assess tumor perfusion and its response to therapies. A significant challenge in the development of reliable biomarkers is a rigorous assessment and optimization of reproducibility. The purpose of this study was to determine the measurement reproducibility of T1-weighted dynamic contrast-enhanced (DCE)-MRI and T2*-weighted dynamic susceptibility contrast (DSC)-MRI with two contrast agents (CA) of different molecular weight (MW): gadopentetate (Gd-DTPA, 0.5 kDa) and Gadomelitol (P792, 6.5 kDa). Each contrast agent was tested with eight mice that had subcutaneous MDA-MB-231 breast xenograft tumors. Each mouse was imaged with a combined DSC-DCE protocol three times within one week to achieve measures of reproducibility. DSC-MRI results were evaluated with a contrast to noise ratio (CNR) efficiency threshold. There was a clear signal drop (>95% probability threshold) in the DSC of normal tissue, while signal changes were minimal or non-existent (<95% probability threshold) in tumors. Mean within-subject coefficient of variation (wCV) of relative blood volume (rBV) in normal tissue was 11.78% for Gd-DTPA and 6.64% for P792. The intra-class correlation coefficient (ICC) of rBV in normal tissue was 0.940 for Gd-DTPA and 0.978 for P792. The inter-subject correlation coefficient was 0.092. Calculated Ktrans from DCE-MRI showed comparable reproducibility (mean wCV, 5.13% for Gd-DTPA, 8.06% for P792). ICC of Ktrans showed high intra-subject reproducibility (ICC?=?0.999/0.995) and inter-subject heterogeneity (ICC?=?0.774). Histograms of Ktrans distributions for three measurements had high degrees of overlap (sum of difference of the normalized histograms <0.01). These results represent homogeneous intra-subject measurement and heterogeneous inter-subject character of biological population, suggesting that perfusion MRI could be an imaging biomarker to monitor or predict response of disease. PMID:24587040

Zhang, Xiaomeng; Pagel, Mark D.; Baker, Amanda F.; Gillies, Robert J.

2014-01-01

129

Experimental demonstration of producing high resolution zone plates by spatial-frequency multiplication  

SciTech Connect

In an earlier publication, the possibility of producing high resolution zone plates for x-ray applications by spatial-frequency multiplication was analyzed theoretically. The theory predicted that for a daughter zone plate generated from the interference of mth and nth diffraction orders of a parent zone plate, its primary focal spot size and focal length are one (m + n)th of their counterparts of the parent zone plate, respectively. It was also shown that a zone plate with the outermost zone width of as small as 13.8 nm might be produced by this technique. In this paper, we report an experiment which we carried out with laser light (lambda = 4166A) for demonstrating this technique. In addition, an outlook for producing high resolution zone plates for x-ray application is briefly discussed.

Yun, W.B.; Howells, M.R.

1987-01-01

130

Quantizations from reproducing kernel spaces  

SciTech Connect

The purpose of this work is to explore the existence and properties of reproducing kernel Hilbert subspaces of L{sup 2}(C,d{sup 2}z/?) 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. -- Highlights: ? We discuss in detail an interesting decomposition of L{sup 2}, in terms of ladder operators. ? We consider coherent states on this structure and we use them for quantization. ? We show how this structure is related with non hermitian quantum mechanics. ? We consider the relation between different schemes of quantizations.

Twareque Ali, S., E-mail: stali@mathstat.concordia.ca [Department of Mathematics and Statistics, Concordia University, Montréal, Québec, Canada H3G 1M8 (Canada); Bagarello, F., E-mail: fabio.bagarello@unipa.it [Dieetcam, Facoltà di Ingegneria, Università di Palermo, I-90128 Palermo (Italy); Pierre Gazeau, Jean, E-mail: gazeau@apc.univ-paris7.fr [Laboratoire APC, Université Paris 7-Denis Diderot, 10, rue A. Domon et L. Duquet, 75205 Paris Cedex 13 (France)

2013-05-15

131

Implantation of ions produced by the use of high power iodine laser  

Microsoft Academic Search

The iodine high power Prague Asterix Laser System (PALS), emitting radiation at 438nm wavelength (3rd-harmonic of a fundamental radiation wavelength equal to 1315nm), was employed to irradiate in vacuum different metallic targets (Cu, Ag and Ta). The high energy (up to 230J) short (400ps) laser pulses produce non-equilibrium plasma expanding mainly along the normal to the target surface. Plasma contains

L. Torrisi; S Gammino; A. M Mezzasalma; J Badziak; P Parys; J Wolowski; E Woryna; J Krása; L Láska; M Pfeifer; K Rohlena; F. P Boody

2003-01-01

132

Electronic and magnetic properties of carbon nanofoam produced by high-repetition-rate laser ablation  

Microsoft Academic Search

A new form of carbon material, a low-density cluster-assembled carbon nanofoam was produced by high-repetition-rate laser ablation of a glassy carbon target in an ambient non-reactive Ar atmosphere. The foam poses a unique combination of properties, such as one of the lowest solid density and high resistivity, similar to that of amorphous diamond-like films. Electron energy loss spectra demonstrate that

A. V. Rode; R. G. Elliman; E. G. Gamaly; A. I. Veinger; A. G. Christy; S. T. Hyde; B. Lutherdavies

2002-01-01

133

Process and apparatus to produce ultra high purity oxygen from a gaseous feed  

Microsoft Academic Search

A process is described to produce ultra high purity oxygen from a gaseous feed comprising: (a) introducing gaseous feed containing oxygen, light impurities and heavy impurities into an absorbing column; (b) passing gaseous feed up the absorbing column and absorbing heavy impurities from ascending gas into descending liquid; (c) condensing resulting gas, passing a first liquid portion thereof into a

1988-01-01

134

Effects of process parameters on granules properties produced in a high shear granulator  

Microsoft Academic Search

Results of a study on the influence of process parameters such as impeller speed, granulation time and binder viscosity on granule strength and properties are reported. A high shear granulator (Cyclomix manufactured by Hosokawa Micron B.V., The Netherlands) has been used to produce granules. Calcium carbonate (Durcal) was used as feed powder and aqueous polyethylene glycol (PEG) as the binder.

Nejat Rahmanian; Ayman Naji; Mojtaba Ghadiri

2011-01-01

135

innovati nNREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar Cells  

E-print Network

innovati nNREL Produces Highly Efficient, Wide-Bandgap, Thin-Film Solar Cells 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

136

A Highly Accurate Stress Measurement System for Producing Precise X-Ray Masks  

Microsoft Academic Search

A new system that measures stress in film deposited on Si wafers has been developed to produce highly accurate X-ray masks. The system consists of very rigid air sliders, an electrostatic sensor, and a soft-handling wafer chuck. With the system, wafer warp is precisely measured before and after film deposition, and the stress distribution is calculated from those measurements. Wafer

Masatoshi Oda; Atsunobu Une; Ikuo Okada; Shinji Shinohara; Yasuo Nakayama; Hideo Yoshihara

1995-01-01

137

Easy synthesis and characterization of high quality graphene sheets produced from mesocarbon microbeads  

Microsoft Academic Search

An easy method of producing graphene sheets with high quality from mesocarbon microbeads (MCMBs) is demonstrated using oxidation, rapid expansion and ultrasonic treatment. Single layer graphene sheets have been successfully prepared from MCMBs through thermal exfoliation. The structure of the graphene sheets was investigated by scanning and transmission electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. MCMBs expanded mainly

Ying Kong; Dong-Lin Zhao; Li-Zhong Bai; Zeng-Min Shen

2011-01-01

138

Nematode sampling instructions for cotton producers on the Southern High Plains of Texas  

E-print Network

Nematode sampling instructions for cotton producers on the Southern High Plains of Texas Jason E populations of plant parasitic nematodes capable of reducing yield. Nematode samples are typically taken after estimation of nematode populations. In collecting soil samples, several factors, such as sampling method

Behmer, Spencer T.

139

High Radon Emanation Coefficients of Porous Matters Produced through Filtration and Precipitation  

Microsoft Academic Search

Previous theoretical predictions of high radon emanation coefficients were verified in experiments using porous matters artificially produced through filtration and precipitation. Such porous matters were prepared by replicating uranium-bearing waste generating processes used in fuel fabrication facilities in Japan except that radium was employed instead of uranium. In the replication, a liquid containing a trace amount of naturally occurring radium

Tomozo SASAKI; Yasuyoshi GUNJI

2008-01-01

140

Ultra high energy photon showers in magnetic field:angular distribution of produced particles  

E-print Network

Ultra high energy (UHE) photons can initiate electromagnetic showers in magnetic field. We analyze the two processes that determine the development of the shower, $e^+ e^-$ pair creation and synchrotron radiation, and derive formulae for the angular distribution of the produced particles. These formulae are necessary to study the three-dimensional development of the shower.

Massimo Coraddu; Marcello Lissia; Giuseppe Mezzorani

2002-10-07

141

Superplastic behaviour of friction stir processed AZ91 magnesium alloy produced by high pressure die cast  

Microsoft Academic Search

The room temperature and hot tensile properties of AZ91 magnesium alloy produced by high pressure die cast after friction stir processing (FSP) were studied in the present paper. Such process is a modification of classical friction stir welding one in which the sheets are not joined but the stirring action of the tool, on the bulk material, is used to

P. Cavaliere; P. P. De Marco

2007-01-01

142

High-power EUV lithography sources based on gas discharges and laser-produced plasmas  

Microsoft Academic Search

Semiconductor chip manufacturers are expecting to use extreme UV lithography for production in 2009. EUV tools require high power, brilliant light sources at 13.5 nm with collector optics producing 120 W average power at entrance of the illuminator system. Today the power and lifetime of the EUV light source are considered as the most critical issue for EUV lithography. The

Uwe Stamm; Imtiaz Ahmad; Istvan Balogh; H. Birner; D. Bolshukhin; J. Brudermann; S. Enke; Frank Flohrer; Kai Gäbel; S. Götze; G. Hergenhan; Jürgen Kleinschmidt; Diethard Klöpfel; Vladimir Korobotchko; Jens Ringling; Guido Schriever; C. D. Tran; C. Ziener

2003-01-01

143

Pressure-driven, resistive magnetohydrodynamic interchange instabilities in laser-produced high-energy-density plasmas  

E-print Network

laser beam interacting with a solid foil, a plasma bubble 6­9 is similar to those plasmas confined using proton backlighting of laser-foil interactions provide unique opportunities for studying magnetized plasma instabilities in laser-produced high-energy-density plasmas. Time-gated proton radiograph

144

Enablers and Inhibitors to Research Productivity among High and Low Producing Vocational Education Faculty Members.  

ERIC Educational Resources Information Center

Eighty-six vocational education faculty at six research-oriented universities were studied to determine perceived enablers and inhibitors to research productivity. A research productivity index was created to identify unusually high or low producers of research. Results indicate markedly different profiles for each group as well as differences by…

Kelly, Maureen E.

1986-01-01

145

How Does Bennett Woods Elementary School Produce Such High Reading and Writing Achievement?  

Microsoft Academic Search

The authors developed a grounded theory about how a school serving relatively advantaged children produces high reading and writing achievement compared with schools serving similar populations of students. The school's faculty is reading and writing focused, and students experience many books as they receive explicit, demanding instruction (i.e., about how to read words, comprehend, write) connected to content learning. The

Michael Pressley; Lindsey Mohan; Lisa M. Raphael; Lauren Fingeret

2007-01-01

146

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

NASA Astrophysics Data System (ADS)

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.; Batani, D.; Malka, V.; Vinci, T.; Koenig, M.; Benuzzi-Mounaix, A.; Dezulian, R.

2005-05-01

147

Financial effects of the highly pathogenic avian influenza outbreaks on the Turkish broiler producers.  

PubMed

This research aimed at assessing the financial effects of the 2005 to 2006 highly pathogenic avian influenza outbreaks on Turkish broiler enterprises. The data were obtained from an interview survey carried out in 499 enterprises randomly selected from 14 provinces that accounted for 79% of the national broiler production. The research revealed that the contracted broiler producers lost on average 1.38 cycles of production and their management fee reduced by 14.7% in 8 mo after the outbreaks. As a result, the broiler production and the enterprise income declined by 34.8 and 44.3%, respectively. The bank loan of the producers rose by 161%. A total of 93% of the producers did not do any other supplementary work during the idle production period in spite of the fact that broiler production was the only business of 36% of them. Furthermore, more than half of the producers (56%) stated that they were considering expanding their business, but suspended this idea due to the outbreak. Approximately 87% of the producers increased the biosecurity measures after the outbreaks. The nationwide effects of the avian influenza outbreaks on the contracted broilers farms were estimated to be US$100.8 million (US$7,967/broiler house). The futures of the contracted broiler producers are fully dependent upon those of the integrated firms. Any negative effects on the latter appeared to be transferred directly to the former. However, the government neglected the integrated firms in the avian influenza compensation programs. PMID:20371863

Aral, Y; Yalcin, C; Cevger, Y; Sipahi, C; Sariozkan, S

2010-05-01

148

Towards reproducible, scalable lateral molecular electronic devices  

NASA Astrophysics Data System (ADS)

An approach to reproducibly fabricate molecular electronic devices is presented. Lateral nanometer-scale gaps with high yield are formed in Au/Pd nanowires by a combination of electromigration and Joule-heating-induced thermomechanical stress. The resulting nanogap devices are used to measure the electrical properties of small numbers of two different molecular species with different end-groups, namely 1,4-butane dithiol and 1,5-diamino-2-methylpentane. Fluctuations in the current reveal that in the case of the dithiol molecule devices, individual molecules conduct intermittently, with the fluctuations becoming more pronounced at larger biases.

Durkan, Colm; Zhang, Qian

2014-08-01

149

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

150

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

151

Rapid dissolving high potency danazol powders produced by spray freezing into liquid process.  

PubMed

The objective of this study was to investigate the use of organic solvents in the spray freezing into liquid (SFL) particle engineering process to make rapid dissolving high potency danazol powders and to examine their particle size, surface area and dissolution rate. The maximum drug potency produced was 91% for SFL micronized danazol/PVP K-15. XRD indicated that danazol in the high potency SFL powders was amorphous. SEM micrographs revealed that the SFL danazol/PVP K-15 nanostructured aggregates had a porous morphology and were composed of many smooth primary nanoparticles with a diameter of about 100 nm. Surface areas of SFL danazol/PVP K-15 high potency powders were in the range of 28-115 m2/g. The SFL powders exhibited significantly enhanced dissolution rates. The rate of dissolution of micronized bulk danazol was slow; only 30% of the danazol was dissolved in 2 min. However, 95% of danazol was dissolved in only 2 min for the SFL high potency powders. The SFL process offers a highly effective approach to produce high potency danazol nanoparticles contained in larger structured aggregates with rapid dissolution rates, and is especially applicable to delivery systems containing poorly water soluble drugs. PMID:15129981

Hu, Jiahui; Johnston, Keith P; Williams, Robert O

2004-03-01

152

Immune interferon produced to high levels by antigenic stimulation of human lymphocytes with influenza virus  

PubMed Central

Influenza virus stimulation of human lymphocytes induced high levels of immune interferon in lymphocyte cultures. The lymphocytes of normal adults produced approximately 1,000 U/10(6) cells, which was in large part gamma interferon. The lymphocytes of individuals recently vaccinated yielded very high levels (10-50,000 U/10(6) cells) of interferon. The interferon was pH 2 labile, and was not neutralized by antisera to alpha or beta interferon. It did not bind to a monoclonal antibody to alpha interferon, and after partial purification it had characteristics identical to human gamma interferon induced by phytohemagglutinin. The highest yields were produced by treatment of stimulator cells with live virus. Stimulation by whole inactivated virus resulted in lower levels of interferon, and purified hemagglutinin did not induce interferon. The antigen responsible for stimulating the lymphocyte response and interferon induction is a cross- reactive determinant present on all human and non-human influenza viruses tested. PMID:6170714

1981-01-01

153

Miniature whirlwinds produced in the laboratory by high-voltage electrical discharges.  

PubMed

Laboratory experiments showed that under certain conditions of vorticity the electrical heatinig produced by a high-voltage discharge at atmospheric pressure can cause the formation of a miniature tornado-like vortex. Once it forms, this vortex stabilizes the electrical discharge along its axis and changes its character from that of a spark to high-pressure variety of a glow discharge. Electrical and dynamic parameters were measured. By relating observations and measurements made in these experiments to previous work and to analogous situations in nature, it is concluded that the heating produced by electrical discharges in a large storm may play a significant role in forming and maintaining natural tornadoes. PMID:17731044

Ryan, R T; Vonnegut, B

1970-06-12

154

Temporary Threshold Shift Produced by Exposure to High-Frequency Noise  

Microsoft Academic Search

The temporary threshold shift at two minutes (TTS2) produced by exposure to high-frequency noise has been measured in a group having normal hearing. The noise source was filtered white noise. Peak frequencies used were at 16, 19, and 28 kilohertz (kilocycles per second). Sound pressure levels ranged from 85 to 100 dB. Eleven different combinations of spectra and sound pressure

Paul E. Smith Jr

1967-01-01

155

High tensile modulus of carbon nanotube nano-fibers produced by dielectrophoresis  

Microsoft Academic Search

We report an experimental measurement of the high tensile modulus of single-walled carbon nanotube (SWNT) bundles and SWNT nano-fibers produced by dielectrophoresis. The average tensile modulus of the SWNT nano-fibers is 265GPa, much higher than the carbon nanotube fibers spun by other techniques. The tensile modulus increases as the diameter of the fiber decreases due to changes in the dieletrophoretic

Han Zhang; Jie Tang; Pinwen Zhu; Jun Ma; Lu-Chang Qin

2009-01-01

156

Transmission electron microscope investigations on Cu-Ag alloys produced by high-pressure torsion  

NASA Astrophysics Data System (ADS)

Cu-Ag alloys in three different compositions (Cu - 25/50/75wt% Ag) were produced by powder consolidation followed by high-pressure torsion. Deformation was performed till a saturation regime was reached. The generated microstructures were investigated by transmission electron microscopy and vary from ultra-fine grained to nanocrystalline to even partially amorphous structures. Vickers hardness measurements show a strong increase in hardness compared with the pure metals, annealing at 130°C leads to an additional increase in hardness.

Kormout, K. S.; Yang, B.; Pippan, R.

2014-08-01

157

Fatigue behaviour of friction stir processed AZ91 magnesium alloy produced by high pressure die casting  

Microsoft Academic Search

The room temperature fatigue properties of AZ91 magnesium alloy produced by high pressure die casting (HPDC) as cast, heat treated, friction stir processed (FSP) and FSP and heat treated were studied. The fatigue properties of the material were evaluated for the HPDC magnesium alloy in the as-received state and after a solution treatment at 415 °C for 2 h and an ageing

P.. Cavaliere; P. P. De Marco

2007-01-01

158

Cloning to reproduce desired genotypes  

Microsoft Academic Search

Cloned sheep, cattle, goats, pigs and mice have now been produced using somatic cells for nuclear transplantation. Animal cloning is still very inefficient with on average less than 10% of the cloned embryos transferred resulting in a live offspring. However successful cloning of a variety of different species and by a number of different laboratory groups has generated tremendous interest

M. E. Westhusin; C. R. Long; T. Shin; J. R. Hill; C. R. Looney; J. H. Pryor; J. A. Piedrahita

2001-01-01

159

Polydiacetylene-Based High-Throughput Screen for Surfactin Producing Strains of Bacillus subtilis  

PubMed Central

Although traditional mutation is still an attractive approach for strain improvement, it is tedious, time-consuming, and inefficient to screen for surfactin producing strains. To overcome this, we developed a high-throughput screening method for surfactin producing mutants by applying polydiacetylene (PDA) vesicles as sensors with visible chromatic change from blue to red, detected as colorimetric response (CR%) signal, which can even semi-quantify the yields of surfactin. Bacillus subtilis 723 was used as parent strain and multiply mutated with atmospheric and room temperature plasma (ARTP). Mutants were cultured in MicroFlask by Duetz (24 square deepwell plates, Applikon Biotechnology) and surfactin titers were tested in 96-well plates with PDA vesicles. Mutants with surfactin titers above150 mg/L (CR% value above 26%) were selected as high-yield strains and further quantified by HPLC. By integrating MicroFlask cultivation and the PDA vesicles detection, we screened 27,000 mutants and found 37 high-yield strains. From these, one mutant produced 473.6 mg/L surfactin (including 353.1 mg/L C15 surfactin), which was 5.4-fold than that of the parent strain. This method is efficient, cost-effective and provides wider application in screening for various surfactants. PMID:24498439

Zhu, Lingyan; Xu, Qing; Jiang, Ling; Huang, He; Li, Shuang

2014-01-01

160

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

161

Polydiacetylene-based high-throughput screen for surfactin producing strains of Bacillus subtilis.  

PubMed

Although traditional mutation is still an attractive approach for strain improvement, it is tedious, time-consuming, and inefficient to screen for surfactin producing strains. To overcome this, we developed a high-throughput screening method for surfactin producing mutants by applying polydiacetylene (PDA) vesicles as sensors with visible chromatic change from blue to red, detected as colorimetric response (CR%) signal, which can even semi-quantify the yields of surfactin. Bacillus subtilis 723 was used as parent strain and multiply mutated with atmospheric and room temperature plasma (ARTP). Mutants were cultured in MicroFlask by Duetz (24 square deepwell plates, Applikon Biotechnology) and surfactin titers were tested in 96-well plates with PDA vesicles. Mutants with surfactin titers above150 mg/L (CR% value above 26%) were selected as high-yield strains and further quantified by HPLC. By integrating MicroFlask cultivation and the PDA vesicles detection, we screened 27,000 mutants and found 37 high-yield strains. From these, one mutant produced 473.6 mg/L surfactin (including 353.1 mg/L C15 surfactin), which was 5.4-fold than that of the parent strain. This method is efficient, cost-effective and provides wider application in screening for various surfactants. PMID:24498439

Zhu, Lingyan; Xu, Qing; Jiang, Ling; Huang, He; Li, Shuang

2014-01-01

162

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

163

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.degree. to 250.degree. 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.

Smith, Jr., Lawrence A. (Bellaire, TX); Jones, Jr., Edward M. (Friendswood, TX); Hearn, Dennis (Houston, TX)

1984-01-01

164

High bandwidth data recording systems for pulsed power and laser produced plasma experiments  

SciTech Connect

We present two high bandwidth data transmission and recording systems for the measurement of transient signals during pulsed power and laser produced plasmas. These systems use fiber optic cables to transmit analog data over long distances to high bandwidth digitizing oscilloscopes. One system is based on the direct modulation of a laser diode and has a bandwidth of 1.5 GHz. The other system is based upon a Mach-Zehnder modulator and has a bandwidth of 12 GHz, and is limited by the photoreceiver. The signals are recorded on commercial digitizing oscilloscopes that have approximately six effective bits. The transmission systems use many off-the-shelf components from the telecommunications industry and thus have a high reliability and a moderate cost. Investigation of the reduction in optical transmission of the fibers during exposure to high dose radiation will also be discussed.

May, M. J.; Clancy, T.; Fittinghoff, D.; Halvorson, C.; Mills, T.; Nikitin, A.; Perry, T.; Roberson, G. P.; Smith, D.; Teruya, A.; Miller, E. K.; Trainham, C. [Lawrence Livermore National Laboratory, 7000 East Avenue Livermore, California 94550 (United States); Special Technologies Laboratory, Bechtel Nevada, 5520 Ekwill Street, Suite B, Santa Barbara, California 93111 (United States)

2006-10-15

165

High Bandwidth Data Recording Systems for Pulsed Power and Laser Produced Plasma Experiments.  

SciTech Connect

We present two high bandwidth data transmission and recording systems for the measurement of transient signals during pulsed power and laser produced plasmas. These systems use fiber optic cables to transmit analog data over long distances to high bandwidth digitizing oscilloscopes. One system is based on the direct modulation of a laser diode and has a bandwidth of 1.5 GHz. The other system is based upon a fiber-optic Mach-Zehnder modulator and has a bandwidth of 12 GHz, and is limited by the photo receiver. The signals are recorded on commercial digitizing oscilloscopes that have approximately 6 effective bits. The transmission systems use many off-the-shelf components from the telecommunications industry and thus have a high reliability and a moderate cost. Results from recent measurements will be presented. Investigation of the reduction in optical transmission by the fibers during exposure to high dose radiation will also be discussed.

May, M J; Clancy, T; Fittinghoff, D; Halvorson, C; MIlls, T; Nikitin, A; Perry, T; Roberson, P; Smith, D; Teruya, A; Miller, K; Trainham, C

2006-05-02

166

Stable high surface area lactate dehydrogenase particles produced by spray freezing into liquid nitrogen.  

PubMed

Enzyme activities were determined for lactate dehydrogenase (LDH) powder produced by lyophilization, and two fast freezing processes, spray freeze-drying (SFD) and spray freezing into liquid (SFL) nitrogen. The 0.25 mg/mL LDH aqueous feed solutions included either 30 or 100 mg/mL trehalose. The SFL process produced powders with very high enzyme activities upon reconstitution, similar to lyophilization. However, the specific surface area of 13 m(2)/g for SFL was an order of magnitude larger than for lyophilization. In SFD activities were reduced in the spraying step by the long exposure to the gas-liquid interface for 0.1-1s, versus only 2 ms in SFL. The ability to produce stable high surface area submicron particles of fragile proteins such as LDH by SFL is of practical interest in protein storage and in various applications in controlled release including encapsulation into bioerodible polymers. The SFL process has been scaled down for solution volumes <1 mL to facilitate studies of therapeutic proteins. PMID:17027245

Engstrom, Josh D; Simpson, Dale T; Cloonan, Carrie; Lai, Edwina S; Williams, Robert O; Barrie Kitto, G; Johnston, Keith P

2007-02-01

167

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

168

High-order harmonic generation from laser plasma produced by pulses of different duration  

SciTech Connect

The high-order harmonic generation was analyzed by interaction of the femtosecond pulses with the laser plasma produced on the surfaces of various targets. The plasma formation was accomplished by the interaction of the prepulse radiation of different pulse duration (160 fs, 1.5 ps, 210 ps, and 20 ns) with the low-Z (lithium, boron, carbon), medium-Z (manganese, zinc, nickel), and high-Z (silver, barium) targets. We showed that plasma formation conditions play a crucial role in harmonic generation and the optimization of this process mostly depends on the energy of prepulse rather than its intensity at the target surface. These studies also demonstrated that the delay between the prepulse and femtosecond pulse is another important parameter, which distinguishes harmonic generation in the cases of the low- and high-Z targets.

Ganeev, R. A. [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Scientific Association Akadempribor, Academy of Sciences of Uzbekistan, Akademgorodok, Tashkent 700125 (Uzbekistan); Suzuki, M.; Baba, M.; Kuroda, H. [Institute for Solid State Physics, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan)

2007-08-15

169

Effect of Initial Conditions on Reproducibility of Scientific Research  

PubMed Central

Background: It is estimated that about half of currently published research cannot be reproduced. Many reasons have been offered as explanations for failure to reproduce scientific research findings- from fraud to the issues related to design, conduct, analysis, or publishing scientific research. We also postulate a sensitive dependency on initial conditions by which small changes can result in the large differences in the research findings when attempted to be reproduced at later times. Methods: We employed a simple logistic regression equation to model the effect of covariates on the initial study findings. We then fed the input from the logistic equation into a logistic map function to model stability of the results in repeated experiments over time. We illustrate the approach by modeling effects of different factors on the choice of correct treatment. Results: We found that reproducibility of the study findings depended both on the initial values of all independent variables and the rate of change in the baseline conditions, the latter being more important. When the changes in the baseline conditions vary by about 3.5 to about 4 in between experiments, no research findings could be reproduced. However, when the rate of change between the experiments is ?2.5 the results become highly predictable between the experiments. Conclusions: Many results cannot be reproduced because of the changes in the initial conditions between the experiments. Better control of the baseline conditions in-between the experiments may help improve reproducibility of scientific findings. PMID:25132705

Djulbegovic, Benjamin; Hozo, Iztok

2014-01-01

170

Enrichment of HFSE in chlorite-harzburgite produced by high-pressure dehydration of antigorite-serpentinite  

E-print Network

Enrichment of HFSE in chlorite-harzburgite produced by high-pressure dehydration of antigorite oceanic plate. Here we provide field-based and geochemical evidence showing that high-pressure dehydration. Godard (2005), Enrichment of HFSE in chlorite-harzburgite produced by high-pressure dehydration

Demouchy, Sylvie

171

Resumption of postpartum ovarian cyclicity in high-producing Holstein cows.  

PubMed

The objective of this study was to investigate the resumption of ovarian cyclicity postpartum in high-producing dairy cows in commercial dairy farms under subtropical conditions. The cows were kept in a free-stall or tie-stall barn. Milk samples were collected from cows twice weekly, and progesterone in the skim milk was assayed by double-antibody ELISA. Cows were examined rectally and vaginoscopically at 2-week intervals after calving. Body condition score (BCS) and body weights were taken before and after calving. A cow was considered to have resumed ovarian cyclicity on the day of ovulation if followed by regular ovarian cycles. Thirty seven percent (n=20/54) of the cows had normal resumption of ovarian cyclicity (resumption within 45 days after calving), and 63% (n=34/54) had delayed resumption (resumption did not occur until >45 days after calving). Delayed resumption Type I (one or more ovarian cycles with luteal phase >20 days, i.e. prolonged luteal phase; 31.5%) and delayed resumption Type II (first ovulation did not occur until > or =45 days after calving, i.e. delayed first ovulation; 24.1%) were the most common types of delayed resumptions. Almost half (46.3%) of the cows did not resume their ovarian cyclicity until >65 days postpartum. Cows with delayed resumption Type I had a higher incidence of abnormal cervico-vaginal discharge (64.7%) and incomplete uterine involution (94.1%) compared to cows with normal resumption (P<0.01). The BCS of cows with delayed resumption Type II were lower than those of normal resumption cows at 5 weeks and later in the postpartum period (P<0.05). Approximately two-thirds of high-producing cows had delayed resumption of ovarian cyclicity postpartum. Prolonged luteal phase and delayed first ovulation were two important ovarian dysfunctions that delayed postpartum resumption of cyclicity in high-producing dairy cows. PMID:14698054

Shrestha, Hemanta Kumar; Nakao, Toshihiko; Higaki, Tsuneo; Suzuki, Toshihiko; Akita, Masashi

2004-02-01

172

High strength state of UFG steel produced by severe plastic deformation  

NASA Astrophysics Data System (ADS)

An UFG austenitic stainless steel of type 316 was produced by high pressure torsion at two different temperatures. As a result different nanostructures were observed in the investigated alloy characterized by different grain size and dislocation density. It was reported that the steel processed at both temperatures was characterized by significantly enhanced strength, which, in case of the steel processed at 430°C, exceeds the value expected for the given grain size according to Hall-Petch relation. This extra-strength is supposed to be due to the observed nanostructural features as segregations/clusters of solutes in grain boundary area formed by severe plastic deformation.

Enikeev, N. A.; Sauvage, X.; Abramova, M. M.; Murashkin, M. Yu; Valiev, R. Z.

2014-08-01

173

High-resolution music with inaudible high-frequency components produces a lagged effect on human electroencephalographic activities.  

PubMed

High-quality digital sound sources with inaudible high-frequency components (above 20 kHz) have become available because of recent advances in information technology. Listening to such sounds has been shown to increase the ?-band power of an electroencephalogram (EEG). The present study scrutinized the time course of this effect by recording EEG along with autonomic measures (skin conductance level and heart rate) and facial electromyograms (corrugator supercilii and zygomaticus major). Twenty university students (19-24 years old) listened to two types of a 200-s musical excerpt (J. S. Bach's French Suite No. 5) with or without inaudible high-frequency components using a double-blind method. They were asked to rate the sound quality and to judge which excerpt contained high-frequency components. High-? EEG power (10.5-13 Hz) was larger for the excerpt with high-frequency components than for the excerpt without them. This effect was statistically significant only in the last quarter of the period (150-200 s). Participants were not able to distinguish between the excerpts, which did not produce any discernible differences in subjective, autonomic, and facial muscle measures. This study shows that inaudible high-frequency components have an impact on human brain activity without conscious awareness. Unlike a standard test for sound quality, at least 150 s of exposure is required to examine this effect in future research. PMID:24722228

Kuribayashi, Ryuma; Yamamoto, Ryuta; Nittono, Hiroshi

2014-06-18

174

Reproducible EnzymeReproducible Enzyme Assembly and CatalyticAssembly and Catalytic  

E-print Network

Reproducible EnzymeReproducible Enzyme Assembly and CatalyticAssembly and Catalytic Activity Accomplishments #12;Reproducible Enzyme Assembly and CatalyticReproducible Enzyme Assembly and Catalytic Activity in Reusable BioMEMSActivity in Reusable BioMEMS Accomplishment Pro-tagged Pfs enzymes are spatially assembled

Rubloff, Gary W.

175

Optical imaging of shock waves produced by a high-energy electromagnetic transducer  

Microsoft Academic Search

An electromagnetic acoustic transducer (EMAT) and acoustic lens have been constructed to provide reproducible and well characterized acoustic shock waves in water. The peak pressure amplitude variation for the unfocused and focused shock waves was found to be within +or-5%. The focal region has been characterized both optically and by conventional piezoelectric pressure measurements. Optical investigations centre around ruby laser

M. T. Carnell; R. D. Alcock; D. C. Emmony

1993-01-01

176

Spontaneous High Piezoelectricity in Poly(vinylidene fluoride) Nanoribbons Produced by Iterative Thermal Size Reduction Technique.  

PubMed

We produced kilometer-long, endlessly parallel, spontaneously piezoelectric and thermally stable poly(vinylidene fluoride) (PVDF) micro- and nanoribbons using iterative size reduction technique based on thermal fiber drawing. Because of high stress and temperature used in thermal drawing process, we obtained spontaneously polar ? phase PVDF micro- and nanoribbons without electrical poling process. On the basis of X-ray diffraction (XRD) analysis, we observed that PVDF micro- and nanoribbons are thermally stable and conserve the polar ? phase even after being exposed to heat treatment above the melting point of PVDF. Phase transition mechanism is investigated and explained using ab initio calculations. We measured an average effective piezoelectric constant as -58.5 pm/V from a single PVDF nanoribbon using a piezo evaluation system along with an atomic force microscope. PVDF nanoribbons are promising structures for constructing devices such as highly efficient energy generators, large area pressure sensors, artificial muscle and skin, due to the unique geometry and extended lengths, high polar phase content, high thermal stability and high piezoelectric coefficient. We demonstrated two proof of principle devices for energy harvesting and sensing applications with a 60 V open circuit peak voltage and 10 ?A peak short-circuit current output. PMID:25133594

Kanik, Mehmet; Aktas, Ozan; Sen, Huseyin Sener; Durgun, Engin; Bayindir, Mehmet

2014-09-23

177

Influences on the uniformity of sprays produced by gas turbine high shear nozzle/swirler assemblies  

NASA Astrophysics Data System (ADS)

In general, real fuel nozzles do not produce uniform spray patterns. To varying degrees, either because of design or manufacturing defects, asymmetric fuel flux profiles are delivered to the combustor. The resulting fuel-air ratio distributions may promote the production of soot, cause large temperature excursions in the combustor or compromise the operability limits of the combustor. Because modern fuel injectors rely on a delicate balance of fuel and air flows, they are susceptible to perturbations which can result in undesirable fuel spray patterns. An experimental investigation was conducted to determine the effects of a variety of design and manufacturing influences on the spray patterns of a model high shear nozzle/swirler assembly. High resolution patternation data were collected for three groups of perturbations to a baseline assembly. Data were compared on the basis of radial and circumferential fuel flux distributions.

Cohen, J. M.; Rosfjord, T. J.

1990-07-01

178

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. PMID:22526529

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

2013-01-01

179

Fertility in high-producing dairy cows: reasons for decline and corrective strategies for sustainable improvement.  

PubMed

The fertility of dairy cows has declined worldwide and this change is surprising given the importance of good fertility to the dairy industry. The decline in fertility can be explained by management changes within the dairy industry and also negative genetic correlations between milk production and reproduction. Four primary mechanisms that depress fertility in lactating cows are anovulatory and behavioral anestrus (failure to cycle and display estrus), suboptimal and irregular estrous cyclicity (this category includes ovarian disease and subnormal luteal function after breeding), abnormal preimplantation embryo development (may be secondary to poor oocyte quality), and uterine/placental incompetence. The solution for improving fertility in high-producing dairy cows will include both short-term and long-terms components. For the immediate short-term, using high fertility sires and implementing controlled breeding programs will help. Controlled breeding programs improve reproductive efficiency in confinement-style dairy herds and can be combined with post-insemination treatments to enhance fertility. An additional immediate short-term solution involves changing the diet so that dietary ingredients invoke hormonal responses that benefit the reproduction of the cow. The short-term solutions described above do not address the fundamental need for correcting the underlying genetics for reproduction in high-producing dairy cows. Crossbreeding will improve reproductive performance perhaps because it alleviates inbreeding and also lowers production in cows with an extreme high milk production phenotype. The current crisis in dairy reproduction will be permanently solved, however, when the genetics for dairy reproduction are improved through a balanced genetic selection strategy. PMID:17491151

Lucy, M C

2007-01-01

180

One-step hydrotreatment of vegetable oil to produce high quality diesel-range alkanes.  

PubMed

A one-step hydrotreatment of vegetable oil combining deoxygenation and isomerization to directly produce low cloud point, high quality diesel is devised. The Pt/zeolite bifunctional catalysts prepared by using SAPO-11 and ZSM-22 zeolites as supports are used in this process. Catalytic reactions are conducted in a fixed-bed reactor under a hydrogen atmosphere. Over the bifunctional catalyst, 100 % conversion of soybean oil is obtained at 357 °C, 4 MPa, and 1 h(-1), and 80 % organic liquid yield is achieved, which is close to the maximum theoretical liquid yield. In the organic products, the alkanes selectivity is 100 % with an i-alkanes selectivity above 63 %. NH(3)-temperature programmed desorption (TPD), pyridine IR spectroscopy, and other characterization techniques are used to study the effect of the support acidity on the reaction pathway. Over the Pt/zeolite bifunctional catalyst with less strong Lewis acid sites, the reaction proceeds via the decarboxylation plus decarbonylation pathway. This one-step method provides a new strategy to produce low cloud point, high quality diesel from biomass feedstock in a more economic and attractive way. PMID:22764086

Wang, Congxin; Tian, Zhijian; Wang, Lei; Xu, Renshun; Liu, Qianhe; Qu, Wei; Ma, Huaijun; Wang, Bingchun

2012-10-01

181

Improvement of compactin (ML-236B) production by genetic engineering in compactin high-producing Penicillium citrinum.  

PubMed

An increase in compactin (ML-236B) production was achieved by introducing a whole compactin biosynthetic gene cluster or the regulatory gene mlcR into compactin high-producing Penicillium citrinum. In the previous report, we introduced mlcR encoding the positive regulator of compactin biosynthetic genes into compactin high-producing strain no. 41520, and most of the transformants produced higher amounts of compactin. Here, we characterize one of the resulting high producers (strain TIR-35, which produced 50% more compactin) and reveal that TIR-35 contained five copies of mlcR and that early, enhanced expression of mlcR caused compactin overproduction. Similarly, the introduction of mlcR into strain T48.19, which was created previously from strain no. 41520 by introducing a partial compactin biosynthetic gene cluster, enhanced compactin production further. Our results indicated that genetic engineering is an effective tool to improve compactin production, even in compactin high producers. PMID:19277641

Baba, S; Abe, Y; Suzuki, T; Ono, C; Iwamoto, K; Nihira, T; Hosobuchi, M

2009-06-01

182

Optimization of HNA etching parameters to produce high aspect ratio solid silicon microneedles  

NASA Astrophysics Data System (ADS)

High aspect ratio solid silicon microneedles with a concave conic shape were fabricated. Hydrofluoric acid-nitric acid-acetic acid (HNA) etching parameters were characterized and optimized to produce microneedles that have long and narrow bodies with smooth surfaces, suitable for transdermal drug delivery applications. The etching parameters were characterized by varying the HNA composition, the optical mask's window size, the etching temperature and bath agitation. An L9 orthogonal Taguchi experiment with three factors, each having three levels, was utilized to determine the optimal fabrication parameters. Isoetch contours for HNA composition with 0% and 10% acetic acid concentrations were presented and a high nitric acid region was identified to produce microneedles with smooth surfaces. It is observed that an increase in window size indiscriminately increases the etch rate in both the vertical and lateral directions, while an increase in etching temperature beyond 35 °C causes the etching to become rapid and uncontrollable. Bath agitation and sample placement could be manipulated to achieve a higher vertical etch rate compared to its lateral counterpart in order to construct high aspect ratio microneedles. The Taguchi experiment performed suggests that a HNA composition of 2:7:1 (HF:HNO3:CH3COOH), window size of 500 µm and agitation rate of 450 RPM are optimal. Solid silicon microneedles with an average height of 159.4 µm, an average base width of 110.9 µm, an aspect ratio of 1.44, and a tip angle and diameter of 19.2° and 0.38 µm respectively were successfully fabricated.

Hamzah, A. A.; Abd Aziz, N.; Yeop Majlis, B.; Yunas, J.; Dee, C. F.; Bais, B.

2012-09-01

183

Photon dose produced by a high-intensity laser on a solid target  

NASA Astrophysics Data System (ADS)

When a high-intensity laser pulse hits a solid target, its pedestal creates a preplasma. The interaction of the main laser pulse, linearly polarized, with this preplasma produces relativistic electrons. These electrons subsequently penetrate inside the target, with high atomic number, and produce bremsstrahlung emission, which constitutes an x-ray source that may be used in various applications such as radiography of high area density objects, photonuclear studies or positron production. This x-ray source is mainly defined by its photon dose, which depends upon the laser, preplasma and target characteristics. In new facilities the radioprotection layout design can be obtained by numerical simulations, which are somewhat tedious. A simple model giving the photon dose per laser energy unit is obtained by using the mean bremsstrahlung cross section of electrons interacting with the atoms of the conversion target. It is expressed versus the fraction ?el of the laser energy absorbed into the forward hot electrons, their mean kinetic energy E, the photon lobe emission mean angular aperture \\bar{{\\theta}} and the target characteristics, i.e. thickness, element, atomic mass and atomic number. The parameters ?el, E and \\bar{{\\theta}} are analysed by applying the energy and momentum flux conservation laws during the laser-plasma interaction in the relativistic regime in an underdense and overdense plasma, including the hole-boring effect. In addition, these quantities are parametrized versus the normalized laser vector potential a0 and the preplasma scale length Lp by using a full set of numerical simulations, in the laser intensity domain 1018-1021 W cm-2 and preplasma scale length range 0.03-400µm. These simulations are done in two- and three-dimensional geometry with the CALDER particle-in-cell code, which computes the laser-plasma interaction, and with the MCNP Monte Carlo code, which calculates the bremsstrahlung emission. The present model is compared with the simulations and with experimental results.

Compant La Fontaine, A.

2014-08-01

184

Implantation of ions produced by the use of high power iodine laser  

NASA Astrophysics Data System (ADS)

The iodine high power Prague Asterix Laser System (PALS), emitting radiation at 438 nm wavelength (3rd-harmonic of a fundamental radiation wavelength equal to 1315 nm), was employed to irradiate in vacuum different metallic targets (Cu, Ag and Ta). The high energy (up to 230 J) short (400 ps) laser pulses produce non-equilibrium plasma expanding mainly along the normal to the target surface. Plasma contains high charge state ions, with maximum charge states of 27 +, 36 + and 49 + for Cu, Ag and Ta, respectively. Time-of-flight (TOF) measurements, performed with the use of an electrostatic ion energy analyser (IEA) placed along the target normal, indicate that the maximum recorded ion kinetic energy is higher than 900 keV for Cu and Ag ions and than 5 MeV for Ta. The laser-produced ions have been implanted into different substrates (polymers, C, Al, Si and Ti) placed at different distances and angles with respect to the target normal. In order to investigate an implantation depth, a density profile of implanted ions and an implanted dose, the samples have been analysed by using the 1.7 MeV helium Rutherford backscattering spectrometry (RBS). The energies of the ions determined with the use of the RBS analysis are in a good agreement with the ion energies measured with the use of the IEA. The results are presented and discussed giving a special attention to the potential of the ion implantation method for modifying the chemical and physical properties of the implanted materials.

Torrisi, L.; Gammino, S.; Mezzasalma, A. M.; Badziak, J.; Parys, P.; Wolowski, J.; Woryna, E.; Krása, J.; Láska, L.; Pfeifer, M.; Rohlena, K.; Boody, F. P.

2003-07-01

185

A new device that produces and collects multiple electrons per photon could yield inexpensive, high-efficiency  

E-print Network

A new device that produces and collects multiple electrons per photon could yield inexpensive, high of electrons produced per incident photon) exceeding 100%, a value beyond that of all current solar cells electron-hole pair) per absorbed high-energy photon, and this device definitively demonstrates

186

Quasi-convex reproducing kernel meshfree method  

NASA Astrophysics Data System (ADS)

A quasi-convex reproducing kernel approximation is presented for Galerkin meshfree analysis. In the proposed meshfree scheme, the monomial reproducing conditions are relaxed to maximizing the positivity of the meshfree shape functions and the resulting shape functions are referred as the quasi-convex reproducing kernel shape functions. These quasi-convex meshfree shape functions are still established within the framework of the classical reproducing or consistency conditions, namely the shape functions have similar form as that of the conventional reproducing kernel shape functions. Thus this approach can be conveniently implemented in the standard reproducing kernel meshfree formulation without an overmuch increase of computational effort. Meanwhile, the present formulation enables a straightforward construction of arbitrary higher order shape functions. It is shown that the proposed method yields nearly positive shape functions in the interior problem domain, while in the boundary region the negative effect of the shape functions are also reduced compared with the original meshfree shape functions. Subsequently a Galerkin meshfree analysis is carried out by employing the proposed quasi-convex reproducing kernel shape functions. Numerical results reveal that the proposed method has more favorable accuracy than the conventional reproducing kernel meshfree method, especially for structural vibration analysis.

Wang, Dongdong; Chen, Pengjie

2014-09-01

187

Irreproducible Musings on Reproducibility Philip B. Stark  

E-print Network

good. But why? · Reproducibility hard. But why? · Reproducibility hard to sell. But why? · Hard? · Provides (a way to generate) evidence of correctness · Enables re-use, modification, extension was reported to have been done on the processed data? · Was that analysis the right analysis to do

Stark, Philip B.

188

Reproducing Kernel Element Interpolation: Globally Conforming Im  

E-print Network

Reproducing Kernel Element Interpolation: Globally Conforming Im /Cn /P k Hierarchies Shaofan Li1 hierarchies are constructed in the framework of reproducing kernel element method (RKEM) for multi in multiple dimension was the challenge in the early development of finite element methods. It attracted

Li, Shaofan

189

Genomic insights into high exopolysaccharide-producing dairy starter bacterium Streptococcus thermophilus ASCC 1275.  

PubMed

Streptococcus thermophilus ASCC 1275 (ST 1275), a typical dairy starter bacterium, yields the highest known amount (~1,000?mg/L) of exopolysaccharide (EPS) in milk among the species of S. thermophilus. The addition of this starter in milk fermentation exhibited texture modifying properties for fermented dairy foods such as yogurt and cheese in the presence of EPS as its important metabolite. In this genomic study, a novel eps gene cluster for EPS assembly of repeating unit has been reported. It contains two-pair epsC-epsD genes which are assigned to determine the chain length of EPS. This also suggests this organism produces two types of EPSs - capsular and ropy EPS, as observed in our previous studies. Additionally, ST 1275 appears to exhibit effective proteolysis system and sophisticated stress response systems to stressful conditions, and has the highest number of four separate CRISPR/Cas loci. These features may be conducive to milk adaptation of this starter and against undesirable bacteriophage infections which leads to failure of milk fermentation. Insights into the genome of ST 1275 suggest that this strain may be a model high EPS-producing dairy starter. PMID:24827399

Wu, Qinglong; Tun, Hein Min; Leung, Frederick Chi-Ching; Shah, Nagendra P

2014-01-01

190

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

191

Characterization of the fast electrons distribution produced in a high intensity laser target interaction  

NASA Astrophysics Data System (ADS)

Experiments on the Titan laser (˜150 J, 0.7 ps, 2 × 1020 W cm-2) at the Lawrence Livermore National Laboratory were carried out in order to study the properties of fast electrons produced by high-intensity, short pulse laser interacting with matter under conditions relevant to Fast Ignition. Bremsstrahlung x-rays produced by these fast electrons were measured by a set of compact filter-stack based x-ray detectors placed at three angles with respect to the target. The measured bremsstrahlung signal allows a characterization of the fast electron beam spectrum, conversion efficiency of laser energy into fast electron kinetic energy and angular distribution. A Monte Carlo code Integrated Tiger Series was used to model the bremsstrahlung signal and infer a laser to fast electron conversion efficiency of 30%, an electron slope temperature of about 2.2 MeV, and a mean divergence angle of 39°. Simulations were also performed with the hybrid transport code ZUMA which includes fields in the target. In this case, a conversion efficiency of laser energy to fast electron energy of 34% and a slope temperature between 1.5 MeV and 4 MeV depending on the angle between the target normal direction and the measuring spectrometer are found. The observed temperature of the bremsstrahlung spectrum, and therefore the inferred electron spectrum are found to be angle dependent.

Westover, B.; Chen, C. D.; Patel, P. K.; McLean, H.; Beg, F. N.

2014-03-01

192

Characterization of High-Temperature Laser-Produced Plasmas Using Thomson Scattering  

SciTech Connect

Ultraviolet Thomson scattering has been fielded at the Omega Laser Facility to achieve accurate measurements of the plasma conditions in laser-produced high-temperature plasmas. Recent applications to hohlraum targets that have been filled with CH gas or SiO{sub 2} foams have demonstrated a new high temperature plasma regime of importance to laser-plasma interaction studies in a strongly damped regime such as those occurring in indirect drive inertial confinement fusion experiments. The Thomson scattering spectra show the collective ion acoustic features that fit the theory for two ion species plasmas and from which we infer the electron and ion temperature. We find that the electron temperature scales from 2-4 keV when increasing the heater beam energy into the hohlraum from 8-17 kJ, respectively. Simultaneous measurements of the stimulated Raman scattering from a green 527 nm interaction beam show that the reflectivity decreases from 20% to 1% indicating that this instability is strongly damped at high temperatures. These findings support green laser beams as possible driver option for laser-driven fusion experiments.

Glenzer, S H; Froula, D H; Ross, S; Niemann, C; Meezan, N; Divol, L

2005-09-16

193

Fatigue behaviour of friction stir processed AZ91 magnesium alloy produced by high pressure die casting  

SciTech Connect

The room temperature fatigue properties of AZ91 magnesium alloy produced by high pressure die casting (HPDC) as cast, heat treated, friction stir processed (FSP) and FSP and heat treated were studied. The fatigue properties of the material were evaluated for the HPDC magnesium alloy in the as-received state and after a solution treatment at 415 deg. C for 2 h and an ageing treatment at 220 deg. C for 4 h. The heat treatment resulted in a significant increase in the fatigue properties of the HPDC material, while no significance influence of heat treatment was recorded in the FSP condition. The morphology of fracture surfaces was examined by employing a field emission gun scanning electron microscope (FEGSEM)

Cavaliere, P. [INFM-Dept. of 'Ingegneria dell'Innovazione', Engineering Faculty, University of Lecce, Via per Arnesano, 73100, Lecce (Italy)]. E-mail: pasquale.cavaliere@unile.it; De Marco, P.P. [INFM-Dept. of 'Ingegneria dell'Innovazione', Engineering Faculty, University of Lecce, Via per Arnesano, 73100, Lecce (Italy)

2007-03-15

194

Micro-cone targets for producing high energy and low divergence particle beams  

DOEpatents

The present invention relates to micro-cone targets for producing high energy and low divergence particle beams. In one embodiment, the micro-cone target includes a substantially cone-shaped body including an outer surface, an inner surface, a generally flat and round, open-ended base, and a tip defining an apex. The cone-shaped body tapers along its length from the generally flat and round, open-ended base to the tip defining the apex. In addition, the outer surface and the inner surface connect the base to the tip, and the tip curves inwardly to define an outer surface that is concave, which is bounded by a rim formed at a juncture where the outer surface meets the tip.

Le Galloudec, Nathalie

2013-09-10

195

On the highly directional expansion of laser-produced plasmas. [metallic targets  

NASA Technical Reports Server (NTRS)

The expansion of plasmas produced by focusing a CO2 laser pulse onto solid planar targets is discussed. The plasmas are studied using an extreme-ultraviolet spectroheliograph. With titanium and iron targets the plasma blow-off observed in transitions within highly ionized species (e.g., Fe XVI) occurs parallel to the target normal. The plasma is tightly confined to narrow cylindrical structures about 0.7 mm in diameter and is observed as far as 1 cm from the target surface. The electron density is about 2.8 by 10 to the 18th power per cu cm at a distance of 0.7 mm from the target surface and decreases to approximately 6.5 by 10 to the 17th power per cu cm at a distance of 2.9 mm from the surface.

Doschek, G. A.; Feldman, U.; Burkhalter, P. G.; Finn, T.; Feibelman, W. A.

1977-01-01

196

Sources of variability in the reproducibility of food frequency questionnaires.  

PubMed

The reproducibility of food frequency questionnaires varies widely. Since reports of past intake are known to be biased toward the present and the forces of supply and demand affect what people eat at a given point in time, the questionnaire may capture an atypical snapshot of consumption rather than the intended view of unusual consumption. The consumption of regularly consumed foods is the same throughout the year. The consumption of these foods is likely to be highly reproducible at another point in time. The consumption of seasonally consumed foods, however, fluctuates throughout the year, and may have peaks in winter or summer or particular holidays. There may be no common denominator among these foods necessary for the purpose of assessing reproducibility. Therefore, questionnaires that contain a combination of regularly and seasonally consumed foods, will be likely to have problems with reproducibility, the variance depending upon the number of seasonally consumed foods in the questionnaire. This explanation for variability in reproducing food frequency questionnaires raises a question about the importance of assessing reproducibility as a way of evaluating the worth of questionnaires. Perhaps an improved method of collecting data for seasonal foods is what is really needed to improve the quality of data collected. PMID:9670173

Joachim, G

1998-01-01

197

Physiological characterization of the high malic acid-producing Aspergillus oryzae strain 2103a-68.  

PubMed

Malic acid is a C? dicarboxylic acid that is currently mainly used in the food and beverages industry as an acidulant. Because of the versatility of the group of C? dicarboxylic acids, the chemical industry has a growing interest in this chemical compound. As malic acid will be considered as a bulk chemical, microbial production requires organisms that sustain high rates, yields, and titers. Aspergillus oryzae is mainly known as an industrial enzyme producer, but it was also shown that it has a very competitive natural production capacity for malic acid. Recently, an engineered A. oryzae strain, 2103a-68, was presented which overexpressed pyruvate carboxylase, malate dehydrogenase, and a malic acid transporter. In this work, we report a detailed characterization of this strain including detailed rates and yields under malic acid production conditions. Furthermore, transcript levels of the genes of interest and corresponding enzyme activities were measured. On glucose as carbon source, 2103a-68 was able to secrete malic acid at a maximum specific production rate during stationary phase of 1.87 mmol?(g dry weight (DW))?¹?h?¹ and with a yield of 1.49 mol mol?¹. Intracellular fluxes were obtained using ¹³C flux analysis during exponential growth, supporting the success of the metabolic engineering strategy of increasing flux through the reductive cytosolic tricarboxylic acid (rTCA) branch. Additional cultivations using xylose and a glucose/xylose mixture demonstrated that A. oryzae is able to efficiently metabolize pentoses and hexoses to produce malic acid at high titers, rates, and yields. PMID:24413918

Knuf, Christoph; Nookaew, Intawat; Remmers, Ilse; Khoomrung, Sakda; Brown, Stephen; Berry, Alan; Nielsen, Jens

2014-04-01

198

[Construction of high sulphite-producing industrial strain of Saccharomyces cerevisiae].  

PubMed

In the process of beer storage and transportation, off-flavor can be produced for oxidation of beer. Sulphite is important for stabilizing the beer flavor because of its antioxidant activity. However, the low level of sulphite synthesized by the brewing yeast is not enough to stabilize beer flavor. Three enzymes involve sulphite biosynthesis in yeast. One of them, APS kinase (encoded by MET14) plays important role in the process of sulphite formation. In order to construct high sulphite-producing brewing yeast strain for beer production, MET14 gene was cloned and overexpressed in industrial strain of Saccharomyces cerevisiae. Primer 1 (5'-TGTGAATTCCTGTACACCAATGGCTACT-3', EcoR I) and primer 2 (5'-TATAAGCTTGATGA GGTGGATGAAGACG-3', HindIII) were designed according to the MET14 sequence in GenBank. A 1.1kb DNA fragment containing the open reading frame and terminator of MET14 gene was amplified from Saccharomyces cerevisiae YSF-5 by PCR, and inserted into YEp352 to generate recombinant plasmid pMET14. To express MET14 gene properly in S. cerevisiae, the recombinant expression plasmids pPM with URA3 gene as the selection marker and pCPM with URA3 gene and copper resistance gene as the selection marker for yeast transformation were constructed. In plasmid pPM, the PGK1 promoter from plasmid pVC727 was fused with the MET14 gene from pMET14, and the expression cassette was inserted into the plasmid YEp352. The dominant selection marker, copper-resistance gene expression cassette CUP1-MTI was inserted in plasmid pPM to result in pCPM. Restriction enzyme analysis showed that plasmids pPM and pCPM were constructed correctly. The laboratory strain of S. cerevisiae YS58 with ura3, trp1, leu2, his4 auxotroph was transformed with plasmid pPM. Yeast transformants were screened on synthetic minimal medium (SD) containing leucine, histidine and tryptophan. The sulphite production of the transformants carrying pPM was 2 fold of that in the control strain YS58, which showed that the MET14 gene on plasmid pPM was expressed functionally in YS58. The industrial brewing yeast strain YSF-38 was transformed with the plasmid pCPM and yeast transformants were selected on YEPD medium containing 4mmol/L copper sulphate. The recombinant strain carrying pCPM showed a 3.2-fold increase in sulphite production when compared to the host strain YSF-38 under laboratory culture conditions. Flask fermentation under brewing-like conditions was performed in Tsingtao Beer Brewery. The sulphite production of the recombinant strain began to be higher than that of the host strain YSF-38 at the fourth day and reached the maximum at the eighth day. At the end of fermentation, the sulphite produced by recombinant strain is 1.4 fold of that in the host strain. The overexpression of MET14 gene in both laboratory and industrial strains of S. cerevisiae increases the sulphite formation. It is the first time to construct high sulphite-producing industrial strain by functional expression of MET14 in S. cerevisiae. Such study provides the foundation for construction of an excellent brewing yeast strain that can produce proper sulphite and can be used in commercial beer production. PMID:16579462

Qu, Na; He, Xiu-ping; Guo, Xue-na; Liu, Nan; Zhang, Bo-run

2006-02-01

199

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

200

Reproducible and variable genomic rearrangements occur in the developing somatic nucleus of the ciliate Tetrahymena thermophila.  

PubMed Central

We analyzed the extent, reproducibility, and developmental control of genomic rearrangements in the somatic macronucleus of the ciliate Tetrahymena thermophila. To exclude differences caused by genetic polymorphisms, we constructed whole-genome homozygotes, and we compared the homozygous progeny derived from single macronuclear differentiation events. This strategy enabled us to identify a novel form of variable rearrangement and to confirm previous findings that rearranged sequences occur at a high frequency in the Tetrahymena genome. Rearrangements studied here were deletions of both unique and interchromosomally dispersed repetitive DNA sequences involving DNA rejoining of internal, nontelomeric regions of macronuclear DNAs. We showed that although rearrangements of some sequence classes are reproducible among independently developed macronuclei, other specific sequence classes are variably rearranged in macronuclear development. The variable somatic genomes so produced may be the source of phenotypically variant cell lines. Images PMID:3018547

Howard, E A; Blackburn, E H

1985-01-01

201

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

202

Cyanobacteria produce a high variety of hepatotoxic peptides in lichen symbiosis  

PubMed Central

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

2012-01-01

203

Carbapenemase-producing Enterobacteriaceae in a tertiary hospital in Madrid, Spain: high percentage of colistin resistance among VIM-1-producing Klebsiella pneumoniae ST11 isolates.  

PubMed

Here we describe the carbapenemase genes, genetic relatedness and antimicrobial susceptibility data of 123 carbapenemase-producing Enterobacteriaceae (CPE) clinical isolates recovered from 2010 to 2012, comprising Klebsiella pneumoniae (n = 79), Klebsiella oxytoca (n = 13), Serratia marcescens (n = 14), Enterobacter cloacae (n = 12), Enterobacter asburiae (n = 4) and Enterobacter aerogenes (n = 1). VIM-1 was the most common carbapenemase (n = 101) followed by KPC-2 (n = 19), OXA-48 (n = 2) and IMP-22 (n = 1). Among the K. pneumoniae isolates, nine sequence types (STs) were identified but two clones were dominant: ST11 (54/79) containing mainly VIM-1-producing isolates; and ST101 (13/79) constituted by KPC-2-producing strains. Pulsed-field gel electrophoresis (PFGE) showed a higher genetic diversity among the remaining Enterobacteriaceae. Amikacin and fosfomycin were the most active agents with 82.9% and 80.5% susceptibility, respectively. Non-susceptibility to tigecycline was detected in 36.5% of strains. Overall, colistin resistance was 24.7% and was as high as 47% in Enterobacter spp. An increase in colistin resistance from 13.5% to 31.7% was observed among K. pneumoniae isolates during the study period. Resistance was focused on ST11 since 83.3% of colistin-resistant strains belonged to this clone. The high level of colistin resistance observed in this study is worrying with respect to the already limited therapeutic options for infections caused by multidrug-resistant Gram-negative bacteria. PMID:24657043

Pena, Irene; Picazo, Juan J; Rodríguez-Avial, Carmen; Rodríguez-Avial, Iciar

2014-05-01

204

Investigation of the ionization front advance in the pulsed discharge produced by high power surface wave  

SciTech Connect

For many applications long plasma columns generated in short times are required. The possibility of using SW discharges for these purposes depends on the time needed to create the discharge. Therefore it seems to be necessary to investigate the plasma generation by a surface wave in a pulsed regime. In the present paper the mechanism of the ionization front advance in the surface wave produced discharge is investigated. To investigate the ionization front velocity in the SW produced discharge a set-up basing on a standard surfaguide is used. The SW launcher is made from a rectangular waveguide with dimensions 23 x 10 mm{sup 2}. In the SW excitation region the waveguide is narrowed to form a gap of 5 mm width. The quartz tube crosses the waveguide through holes of 6 mm diameter in the wide walls. The tube with inside diameter 4 mm and a length of 50 cm is used. The tube is filled with various gases: air, CO{sub 2}, He, N{sub 2} and their mixtures at pressures p = 1-100 Torr. The experiments are performed using microwave radiation with a wavelength {lambda} = 3 cm, pulse duration {tau} = 1-15 {mu}s, pulse power P = 30-150 kW, the repetition frequency F = 0.1-1 Hz. In this experiment the ionization front velocity along the tube axis is determined by means of a device based on UMI multistage light amplifier. High-speed photography was carried out in the streak-camera mode (the method of photochronography). The measurements of the electric field outside the tube are performed with a coaxial movable antenna. The plasma light emission is observed using a monochromator and photomultiplier.

Boehle, A.; Kortshagen, U.; Schlueter, H. [Ruhr-Univ. Bochum (Germany)] [and others

1995-12-31

205

Optical imaging of shock waves produced by a high-energy electromagnetic transducer.  

PubMed

An electromagnetic acoustic transducer (EMAT) and acoustic lens have been constructed to provide reproducible and well characterized acoustic shock waves in water. The peak pressure amplitude variation for the unfocused and focused shock waves was found to be within +/- 5%. The focal region has been characterized both optically and by conventional piezoelectric pressure measurements. Optical investigations centre around ruby laser illuminated Schlieren and focused shadow imaging. The temporal resolution of the optical technique was determined by the ruby laser pulse length of 20 ns, giving a spatial resolution of 30 microns for a shock front in water. PMID:8272433

Carnell, M T; Alcock, R D; Emmony, D C

1993-11-01

206

High-Energy Neutrinos Produced by Interactions of Relativistic Protons in Shocked Pulsar Winds  

E-print Network

We have estimated fluxes of neutrinos and gamma-rays that are generated from decays of charged and neutral pions from a pulsar surrounded by supernova ejecta in our galaxy, including an effect that has not been taken into consideration, that is, interactions between high energy cosmic rays themselves in the nebula flow, assuming that hadronic components are the energetically dominant species in the pulsar wind. Bulk flow is assumed to be randomized by passing through the termination shock and energy distribution functions of protons and electrons behind the termination shock are assumed to obey the relativistic Maxwellians. We have found that fluxes of neutrinos and gamma-rays depend very sensitively on the wind luminosity, which is assumed to be comparable to the spin-downluminosity. In the case where B=10^{12}G and P=1ms, neutrinos should be detected by km^3 high-energy neutrino detectors such as AMANDA and IceCube. Also, gamma-rays should be detected by Cherenkov telescopes such as CANGAROO and H.E.S.S. as well as by gamma-ray satellites such as GLAST. On the other hand, in the case where B=10^{12}G and P=5ms, fluxes of neutrinos and gamma-rays will be too low to be detected even by the next-generation detectors. However, even in the case where B=10^{12}G and P=5ms, there is a possibility that very high fluxes of neutrinos may be realized at early stage of a supernova explosion (t \\le 1yr), where the location of the termination shock is very near to the pulsar. We also found that there is a possibility that protons with energies \\sim 10^5 GeV in the nebula flow may interact with the photon field from surface of the pulsar and produce much pions, which enhances the intensity of resulting neutrinos and gamma-rays.

S. Nagataki

2003-09-26

207

Multiple Species of Trichosporon Produce Biofilms Highly Resistant to Triazoles and Amphotericin B  

PubMed Central

Invasive infections caused by Trichosporon spp. have increased considerably in recent years, especially in neutropenic and critically ill patients using catheters and antibiotics. The genus presents limited sensitivity to different antifungal agents, but triazoles are the first choice for treatment. Here, we investigated the biofilm production and antifungal susceptibility to triazoles and amphotericin B of 54 Trichosporon spp. isolates obtained from blood samples (19), urine (20) and superficial mycosis (15). All isolates and 7 reference strains were identified by sequence analysis and phylogenetic inferences of the IGS1 region of the rDNA. Biofilms were grown on 96-well plates and quantitation was performed using crystal violet staining, complemented with Scanning Electron Microscopy (SEM). Susceptibility tests for fluconazole, itraconazole, voriconazole and amphotericin B were processed using the microdilution broth method (CLSI) for planktonic cells and XTT reduction assay for biofilm-forming cells. Our results showed that T. asahii was the most frequent species identified (66.7%), followed by T. faecale (11.1%), T. asteroides (9.3%), T. inkin (7.4%), T. dermatis (3.7%) and one T. coremiiforme (1.8%). We identified 4 genotypes within T. asahii isolates (G1, G3, G4 and G5) and 2 genotypes within T. faecale (G1 and G3). All species exhibited high adhesion and biofilm formation capabilities, mainly T. inkin, T. asteroides and T. faecale. Microscopy images of high biofilm-producing isolates showed that T. asahii presented mainly hyphae and arthroconidia, whereas T. asteroides exhibited mainly short arthroconidia and few filaments. Voriconazole exhibited the best in vitro activity against all species tested. Biofilm-forming cells of isolates and reference strains were highly resistant to all antifungals tested. We concluded that levels of biofilm formation by Trichosporon spp. were similar or even greater than those described for the Candida genus. Biofilm-forming cells were at least 1,000 times more resistant to antifungals than planktonic cells, especially to voriconazole. PMID:25360765

Iturrieta-Gonzalez, Isabel Antonieta; Padovan, Ana Carolina Barbosa; Bizerra, Fernando Cesar; Hahn, Rosane Christine; Colombo, Arnaldo Lopes

2014-01-01

208

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

209

Energy deposition at the bone-tissue interface from nuclear fragments produced by high-energy nucleons  

NASA Technical Reports Server (NTRS)

The transport of nuclear fragmentation recoils produced by high-energy nucleons in the region of the bone-tissue interface is considered. Results for the different flux and absorbed dose for recoils produced by 1 GeV protons are presented in a bidirectional transport model. The energy deposition in marrow cavities is seen to be enhanced by recoils produced in bone. Approximate analytic formulae for absorbed dose near the interface region are also presented for a simplified range-energy model.

Cucinotta, Francis A.; Hajnal, Ferenc; Wilson, John W.

1990-01-01

210

Reproducibility and utility of dune luminescence chronologies  

NASA Astrophysics Data System (ADS)

Optically stimulated luminescence (OSL) dating of dune deposits has increasingly been used as a tool to investigate the response of aeolian systems to environmental change. Amalgamation of individual dune accumulation chronologies has been employed in order to distinguish regional from local geomorphic responses to change. However, advances in dating have produced chronologies of increasing complexity. In particular, questions regarding the interpretation of dune ages have been raised, including over the most appropriate method to evaluate the significance of suites of OSL ages when local 'noisy' and discontinuous records are combined. In this paper, these issues are reviewed and the reproducibility of dune chronologies is assessed. OSL ages from two cores sampled from the same dune in the northeast Rub' al Khali, United Arab Emirates, are presented and compared, alongside an analysis of previously published dune ages dated to within the last 30 ka. Distinct periods of aeolian activity and preservation are identified, which can be tied to regional climatic and environmental changes. This case study is used to address fundamental questions that are persistently asked of dune dating studies, including the appropriate spatial scale over which to infer environmental and climatic change based on dune chronologies, whether chronological hiatuses can be interpreted, how to most appropriately combine and display datasets, and the relationship between geomorphic and palaeoclimatic signals. Chronological profiles reflect localised responses to environmental variability and climatic forcing, and amalgamation of datasets, with consideration of sampling resolution, is required; otherwise local factors are always likely to dominate. Using net accumulation rates to display ages may provide an informative approach of analysing and presenting dune OSL chronologies less susceptible to biases resulting from insufficient sampling resolution.

Leighton, Carly L.; Thomas, David S. G.; Bailey, Richard M.

2014-02-01

211

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double pulses  

E-print Network

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double laser-produced plasmas are bright ultrafast line x-ray sources potentially suitable for different onto a solid target into the x-ray emission is significantly enhanced when a laser prepulse precedes

Limpouch, Jiri

212

Real-time measurement of materials properties at high temperatures by laser produced plasmas  

NASA Technical Reports Server (NTRS)

Determination of elemental composition and thermophysical properties of materials at high temperatures, as visualized in the context of containerless materials processing in a microgravity environment, presents a variety of unusual requirements owing to the thermal hazards and interferences from electromagnetic control fields. In addition, such information is intended for process control applications and thus the measurements must be real time in nature. A new technique is described which was developed for real time, in-situ determination of the elemental composition of molten metallic alloys such as specialty steel. The technique is based on time-resolved spectroscopy of a laser produced plasma (LPP) plume resulting from the interaction of a giant laser pulse with a material target. The sensitivity and precision were demonstrated to be comparable to, or better than, the conventional methods of analysis which are applicable only to post-mortem specimens sampled from a molten metal pool. The LPP technique can be applied widely to other materials composition analysis applications. The LPP technique is extremely information rich and therefore provides opportunities for extracting other physical properties in addition to the materials composition. The case in point is that it is possible to determine thermophysical properties of the target materials at high temperatures by monitoring generation and transport of acoustic pulses as well as a number of other fluid-dynamic processes triggered by the LPP event. By manipulation of the scaling properties of the laser-matter interaction, many different kinds of flow events, ranging from shock waves to surface waves to flow induced instabilities, can be generated in a controllable manner. Time-resolved detection of these events can lead to such thermophysical quantities as volume and shear viscosities, thermal conductivity, specific heat, mass density, and others.

Kim, Yong W.

1990-01-01

213

Application of dielectric spectroscopy for monitoring high cell density in monoclonal antibody producing CHO cell cultivations.  

PubMed

The application of dielectric spectroscopy was frequently investigated as an on-line cell culture monitoring tool; however, it still requires supportive data and experience in order to become a robust technique. In this study, dielectric spectroscopy was used to predict viable cell density (VCD) at industrially relevant high levels in concentrated fed-batch culture of Chinese hamster ovary cells producing a monoclonal antibody for pharmaceutical purposes. For on-line dielectric spectroscopy measurements, capacitance was scanned within a wide range of frequency values (100-19,490 kHz) in six parallel cell cultivation batches. Prior to detailed mathematical analysis of the collected data, principal component analysis (PCA) was applied to compare dielectric behavior of the cultivations. PCA analysis resulted in detecting measurement disturbances. By using the measured spectroscopic data, partial least squares regression (PLS), Cole-Cole, and linear modeling were applied and compared in order to predict VCD. The Cole-Cole and the PLS model provided reliable prediction over the entire cultivation including both the early and decline phases of cell growth, while the linear model failed to estimate VCD in the later, declining cultivation phase. In regards to the measurement error sensitivity, remarkable differences were shown among PLS, Cole-Cole, and linear modeling. VCD prediction accuracy could be improved in the runs with measurement disturbances by first derivative pre-treatment in PLS and by parameter optimization of the Cole-Cole modeling. PMID:23801499

Párta, László; Zalai, Dénes; Borbély, Sándor; Putics, Akos

2014-02-01

214

Thin silicon foils produced by epoxy-induced spalling of silicon for high efficiency solar cells  

NASA Astrophysics Data System (ADS)

We report on the drastic improvement of the quality of thin silicon foils produced by epoxy-induced spalling. In the past, researchers have proposed to fabricate silicon foils by spalling silicon substrates with different stress-inducing materials to manufacture thin silicon solar cells. However, the reported values of effective minority carrier lifetime of the fabricated foils remained always limited to ˜100 ?s or below. In this work, we investigate epoxy-induced exfoliated foils by electron spin resonance to analyze the limiting factors of the minority carrier lifetime. These measurements highlight the presence of disordered dangling bonds and dislocation-like defects generated by the exfoliation process. A solution to remove these defects compatible with the process flow to fabricate solar cells is proposed. After etching off less than 1 ?m of material, the lifetime of the foil increases by more than a factor of 4.5, reaching a value of 461 ?s. This corresponds to a lower limit of the diffusion length of more than 7 times the foil thickness. Regions with different lifetime correlate well with the roughness of the crack surface which suggests that the lifetime is now limited by the quality of the passivation of rough surfaces. The reported values of the minority carrier lifetime show a potential for high efficiency (>22%) thin silicon solar cells.

Martini, R.; Kepa, J.; Debucquoy, M.; Depauw, V.; Gonzalez, M.; Gordon, I.; Stesmans, A.; Poortmans, J.

2014-10-01

215

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

216

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

217

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

Microsoft Academic Search

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,

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

1999-01-01

218

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

Microsoft Academic Search

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,

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

1997-01-01

219

The attitudes and opinions toward sustainable agriculture of agricultural producers on the High Plains of Texas.  

E-print Network

??Several issues are facing agricultural producers, including water conservation, sustainability, legislation, and carbon sequestration. Understanding the issues facing farmers, as well as the attitudes and… (more)

Frederick, Caitlin

2010-01-01

220

Reproducing or Challenging Power in the Questions We Ask and the Methods We Use: A Framework for Activist Research in Urban Education  

ERIC Educational Resources Information Center

Many have argued that educational research does little to change (and may actually reproduce) the social-structural inequalities shaping the quality of high-poverty urban schools. Building from this premise, this paper asks: How can university-based scholars of urban education do research that encourages, produces, or informs change in urban…

Nygreen, Kysa

2006-01-01

221

Selection of candidate aquatic high plants as producer of closed aquatic ecosystem  

NASA Astrophysics Data System (ADS)

Controlled Ecological Life Support Systems (CELSS) is very important for long-term manned space flight. Aquatic organism was regarded to be suitable for this study because of their great adaptation to the weightless condition which approximate to their wild condition in water. In order to study of operation of CELSS in space, the first step is to choose good candidate species for study. In this report, we compared the characteristics of nutrient content, growth and suitability with animals among five types of aquatic high plants including Ceratophyllum demersum L., Vallisneria spiralis L., Hydrilla verticillata Royle, Brasenia schreberi, Wolfia arrhiza under control condition. It was found that B. schreberi had the best nutrients content, but it growth depended on gas interface which may be a big problem in microgravity. C. demersum and W. arrhiza had the better nutrient content than other types, and V. spiralis and H. verticillata had the worst nutrient content. The closed aquatic system can provided condition for the growth of other plants than B. schreberi. So we selected C. demersum and W. arrhiza as the candidate of producer for establish Closed Aquatic Ecosystem. We also established a simple system& by housing three small freshwater snails (Bulinus australianus) and C. demersum in a 500mL box with light and temperature control. The values about pH, oxygen concentration, temperature and light had been acquired by sensors in real time for about 3 month. It was found that plant's biomass increased for several days and then leveled off and the snails survive, and the atmosphere and biomass for food met snails' requirement during experiments.

Wang, Gaohong; Hao, Zongjie; Liu, Yongding

222

Reproducibility responsibilities in the HPC arena  

SciTech Connect

Expecting bit-for-bit reproducibility in the HPC arena is not feasible because of the ever changing hardware and software. No user s application is an island; it lives in an HPC eco-system that changes over time. Old hardware stops working and even old software won t run on new hardware. Further, software libraries change over time either by changing the internals or even interfaces. So bit-for-bit reproducibility should not be expected. Rather a reasonable expectation is that results are reproducible within error bounds; or that the answers are close (which is its own debate.) To expect a researcher to reproduce their own results or the results of others within some error bounds, there must be enough information to recreate all the details of the experiment. This requires complete documentation of all phases of the researcher s workflow; from code to versioning to programming and runtime environments to publishing of data. This argument is the core statement of the Yale 2009 Declaration on Reproducible Research [1]. Although the HPC ecosystem is often outside the researchers control, the application code could be built almost identically and there is a chance for very similar results with just only round-off error differences. To achieve complete documentation at every step, the researcher, the computing center, and the funding agencies all have a role. In this thesis, the role of the researcher is expanded upon as compared to the Yale report and the role of the computing centers is described.

Fahey, Mark R [ORNL; McLay, Robert [Texas Advanced Computing Center

2014-01-01

223

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

224

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

PubMed Central

Retroviral-mediated gene transfer into primitive hematopoietic cells has been difficult to achieve in large-animal models. We have developed an amphotropic producer clone that generates greater than 10(10) recombinant retroviral particles (colony-forming units) per ml of culture medium. Autologous rhesus monkey bone-marrow cells were cocultured with either high (2 x 10(10) colony-forming units/ml) or low (5 x 10(6) colony-forming units/ml) 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. Images PMID:2339117

Bodine, D M; McDonagh, K T; Brandt, S J; Ney, P A; Agricola, B; Byrne, E; Nienhuis, A W

1990-01-01

225

MASSIVE DATA, THE DIGITIZATION OF SCIENCE, AND REPRODUCIBILITY OF RESULTS  

SciTech Connect

As the scientific enterprise becomes increasingly computational and data-driven, the nature of the information communicated must change. Without inclusion of the code and data with published computational results, we are engendering a credibility crisis in science. Controversies such as ClimateGate, the microarray-based drug sensitivity clinical trials under investigation at Duke University, and retractions from prominent journals due to unverified code suggest the need for greater transparency in our computational science. In this talk I argue that the scientific method be restored to (1) a focus on error control as central to scientific communication and (2) complete communication of the underlying methodology producing the results, ie. reproducibility. I outline barriers to these goals based on recent survey work (Stodden 2010), and suggest solutions such as the “Reproducible Research Standard” (Stodden 2009), giving open licensing options designed to create an intellectual property framework for scientists consonant with longstanding scientific norms.

None

2010-07-02

226

Tract Specific Reproducibility of Tractography Based Morphology and Diffusion Metrics  

PubMed Central

Introduction The reproducibility of tractography is important to determine its sensitivity to pathological abnormalities. The reproducibility of tract morphology has not yet been systematically studied and the recently developed tractography contrast Tract Density Imaging (TDI) has not yet been assessed at the tract specific level. Materials and Methods Diffusion tensor imaging (DTI) and probabilistic constrained spherical deconvolution (CSD) tractography are performed twice in 9 healthy subjects. Tractography is based on common space seed and target regions and performed for several major white matter tracts. Tractograms are converted to tract segmentations and inter-session reproducibility of tract morphology is assessed using Dice similarity coefficient (DSC). The coefficient of variation (COV) and intraclass correlation coefficient (ICC) are calculated of the following tract metrics: fractional anisotropy (FA), apparent diffusion coefficient (ADC), volume, and TDI. Analyses are performed both for proximal (deep white matter) and extended (including subcortical white matter) tract segmentations. Results Proximal DSC values were 0.70–0.92. DSC values were 5–10% lower in extended compared to proximal segmentations. COV/ICC values of FA, ADC, volume and TDI were 1–4%/0.65–0.94, 2–4%/0.62–0.94, 3–22%/0.53–0.96 and 8–31%/0.48–0.70, respectively, with the lower COV and higher ICC values found in the proximal segmentations. Conclusion For all investigated metrics, reproducibility depended on the segmented tract. FA and ADC had relatively low COV and relatively high ICC, indicating clinical potential. Volume had higher COV but its moderate to high ICC values in most tracts still suggest subject-differentiating power. Tract TDI had high COV and relatively low ICC, which reflects unfavorable reproducibility. PMID:22485157

Besseling, Rene M. H.; Jansen, Jacobus F. A.; Overvliet, Geke M.; Vaessen, Maarten J.; Braakman, Hilde M. H.; Hofman, Paul A. M.; Aldenkamp, Albert P.; Backes, Walter H.

2012-01-01

227

Supplemental Figure 1 Reproducibility of biological replicates.  

E-print Network

Supplemental Figure 1 Reproducibility of biological replicates. (A) Pairwise comparisons of three. In these replicates the SILAC labels were switched, hence the negative correlation. Supplemental Figure 2 Curation in the SCUD database with those identified in this publication. Supplemental Figure 3 Changes in the Ub

Martin, Alain

228

Reproducibility in Ultrasonic Characterization of Carotid Plaques  

Microsoft Academic Search

Background and Purpose: Echolucent carotid plaques compared with echogenic plaques could carry a significant risk of transient ischemic attacks and strokes, but the reproducibility of new ultrasonic methods has not yet been proved. The objective was to evaluate interobserver and intraobserver agreement in characterizing the carotid plaques studied by both B mode imaging and color Doppler imaging, which is the

J. M. de Bray; J. M. Baud; P. Delanoy; J. P. Camuzat; V. Dehans; J. Descamp-Le Chevoir; J. R. Launay; F. Luizy; Y. Sentou; P. Cales

1998-01-01

229

Reproducibility, Controllability, and Optimization of Lenr Experiments  

NASA Astrophysics Data System (ADS)

Low-energy nuclear reaction (LENR) measurements are significantly and increasingly reproducible. Practical control of the production of energy or materials by LENR has yet to be demonstrated. Minimization of costly inputs and maximization of desired outputs of LENR remain for future developments.

Nagel, David J.

2006-02-01

230

Reproducibility, Controllability, and Optimization of Lenr Experiments  

Microsoft Academic Search

Low-energy nuclear reaction (LENR) measurements are significantly and increasingly reproducible. Practical control of the production of energy or materials by LENR has yet to be demonstrated. Minimization of costly inputs and maximization of desired outputs of LENR remain for future developments.

David J. Nagel

2006-01-01

231

Human Computation Must Be Reproducible Praveen Paritosh  

E-print Network

Human Computation Must Be Reproducible Praveen Paritosh Google 345 Spear St, San Francisco, CA 94105. pkp@google.com ABSTRACT Human computation is the technique of performing a com- putational and evaluation of experiments. We argue that human computation has similar properties, and that the results

Tomkins, Andrew

232

Is My Network Module Preserved and Reproducible?  

Microsoft Academic Search

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

Peter Langfelder; Rui Luo; Michael C. Oldham; Steve Horvath; Philip E. Bourne

2011-01-01

233

Reproducible Measurements of MPI Performance Characteristics  

E-print Network

of the mistakes often made in attempting such mea- surements and the consequences of such mistakes. We describe, that attempts to avoid such mistakes and obtain reproducible measures of MPI performance that can be useful, Information, and Computational Sci- ences Division subprogram of the Office of Advanced Scientific Computing

Gropp, Bill

234

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 key,…

Lobb, Nancy

235

Reproducible Clusters from Microarray Research: Whither?  

Microsoft Academic Search

MOTIVATION: In cluster analysis, the validity of specific solutions, algorithms, and procedures present significant challenges because there is no null hypothesis to test and no 'right answer'. It has been noted that a replicable classification is not necessarily a useful one, but a useful one that characterizes some aspect of the population must be replicable. By replicable we mean reproducible

Nikhil R. Garge; Grier P. Page; Alan P. Sprague; Bernard S. Gorman; David B. Allison

2005-01-01

236

High prevalence of faecal carriage of ESBL-producing Enterobacteriaceae in Norwegian patients with gastroenteritis.  

PubMed

We conducted a cross-sectional study to examine the prevalence of faecal carriage of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in patients with gastroenteritis. During April 2011, all faecal samples submitted to our hospital laboratory were examined for ESBL-producing Enterobacteriaceae. Isolates expressing an ESBL phenotype were investigated for the presence of genes encoding broad-spectrum beta-lactamases, ESBLs, carbapenemases, and plasmid-mediated AmpC. Information on age, gender, and travel history was extracted from the laboratory records. In total 273 faecal samples were included. The overall carrier rate in the study population was 15.8%. The ESBL carrier rate among patients with no history of recent travel, or where this information was missing, was 10.3%. In contrast, the carrier rate was 56.3% (odds ratio 16.3, p < 0.001) among patients with a record of travel to Asia. Two ESBL-producing isolates were identified as enteropathogenic Escherichia coli. Co-resistance between third-generation cephalosporins, trimethoprim-sulfamethoxazole, and fluoroquinolones was seen in 49% of isolates. No carbapenemase-producers were found. PMID:24702690

Jørgensen, Silje Bakken; Samuelsen, Orjan; Sundsfjord, Arnfinn; Bhatti, Sidra Ahmad; Jørgensen, Ingvild; Sivapathasundaram, Thusanth; Leegaard, Truls Michael

2014-06-01

237

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

238

Understanding high wintertime ozone pollution events in an oil and natural gas producing region of the western US  

NASA Astrophysics Data System (ADS)

Recent increases in oil and natural gas (NG) production throughout the western US have come with scientific and public interest in emission rates, air quality and climate impacts related to this industry. This study uses a regional scale air quality model WRF-Chem to simulate high ozone (O3) episodes during the winter of 2013 over the Uinta Basin (UB) in northeastern Utah, which is densely populated by thousands of oil and NG wells. The high resolution meteorological simulations are able to qualitatively reproduce the wintertime cold pool conditions that occurred in 2013, allowing the model to reproduce the observed multi-day buildup of atmospheric pollutants and accompanying rapid photochemical ozone formation in the UB. Two different emission scenarios for the oil and NG sector were employed in this study. The first emission scenario (bottom-up) was based on the US EPA National Emission Inventory (NEI) (2011, version 1) for the oil and NG sector for the UB. The second emission scenario (top-down) was based on the previously derived estimates of methane (CH4) emissions and a regression analysis for multiple species relative to CH4 concentration measurements in the UB. WRF-Chem simulations using the two emission data sets resulted in significant differences for concentrations of most gas-phase species. Evaluation of the model results shows greater underestimates of CH4 and other volatile organic compounds (VOCs) in the simulation with the NEI-2011 inventory than the case when the top-down emission scenario was used. Unlike VOCs, the NEI-2011 inventory significantly overestimates the emissions of nitrogen oxides (NOx), while the top-down emission scenario results in a moderate negative bias. Comparison of simulations using the two emission data sets reveals that the top-down case captures the high O3 episodes. In contrast, the simulation case using the bottom-up inventory is not able to reproduce any of the observed high O3 concentrations in the UB. A sensitivity analysis reveals that the major factors driving high wintertime O3 in the UB are shallow boundary layers with light winds, high emissions of VOCs from oil and NG operations compared to NOx emissions, enhancement of photolysis fluxes and reduction of O3 loss from deposition due to snow cover. Simple emission reduction scenarios show that the UB O3 production is VOC sensitive and NOx insensitive. The model results show a disproportionate contribution of aromatic VOCs to O3 formation relative to all other VOC emissions. We also present modeling results for winter of 2012, when high O3 levels were not observed in the UB. The air quality model together with the top-down emission framework presented here may help to address the emerging science and policy related questions surrounding the environmental impact of oil and NG drilling in western US.

Ahmadov, R.; McKeen, S.; Trainer, M.; Banta, R.; Brewer, A.; Brown, S.; Edwards, P. M.; de Gouw, J. A.; Frost, G. J.; Gilman, J.; Helmig, D.; Johnson, B.; Karion, A.; Koss, A.; Langford, A.; Lerner, B.; Olson, J.; Oltmans, S.; Peischl, J.; Pétron, G.; Pichugina, Y.; Roberts, J. M.; Ryerson, T.; Schnell, R.; Senff, C.; Sweeney, C.; Thompson, C.; Veres, P.; Warneke, C.; Wild, R.; Williams, E. J.; Yuan, B.; Zamora, R.

2014-08-01

239

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

240

Generation of high-charge-state ions from CO2 laser-produced plasma  

Microsoft Academic Search

The measurement results are presented for angular dependency of the CO2 laser produced plasma parameters at power density of 4 by 1013W\\/cm2 and laser pulse duration of 14 ns. 2D numerical simulations are in sufficiently good agreement with experiment. It is shown that the light pressure effects on plasma expansion dynamics and the number of particles generated at the target

K. N. Makarov; S. V. Khomenko; S. G. Nischuk; V. C. Roerich; Yu. A. Satov; Yu. B. Smakovskii; A. E. Stepanov

2001-01-01

241

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

242

X-ray spectral line shapes for the excimer-laser-produced high density plasma diagnostics  

Microsoft Academic Search

The time and space-integrated emission spectra measurements have been performed in plasma produced by 308 nm wavelength XeCl laser radiation (IL=(4-10).1012 W\\/cm2, tau=10 ns) and by 248 nm wavelength KrF laser pulse train radiation IL=5.1015 W\\/cm2, tau=7 ps, 16 pulses in train) on (CFn plane target. The lines' shapes and intensities modeling of Lyman series and He-like ion resonance series

A. Magunov; A. Faenov; I. Skobelev; T. Pikuz; D. Batani; M. Milani; A. Conti; A. Masini; M. Costato; A. Pozzi; E. Turcu; R. Allot; N. Lisi; M. Koenig; A. Benuzzi; F. Flora; T. Letardi; L. Palladino; A. Reale

1997-01-01

243

Dynamics of high-Z plasmas produced by a short-wavelength laser  

Microsoft Academic Search

The dynamics and energy flow in Au plasmas produced by a 0.35-mum laser have been studied with layered targets with 6- and 24-beam spherical illumination from the Omega laser, to understand the processes leading to sub-keV x-ray emission. A significant enhancement in x-ray conversion at low intensities is observed for the 24-beam irradiations with higher energy, greater uniformity, and larger

P. D. Goldstone; S. R. Goldman; W. C. Mead; J. A. Cobble; G. Stradling; R. H. Day; A. Hauer; M. C. Richardson; R. S. Marjoribanks; P. A. Jaanimagi; R. L. Keck; F. J. Marshall; W. Seka; O. Barnouin; B. Yaakobi; S. A. Letzring

1987-01-01

244

High field-effect mobility zinc oxide thin film transistors produced at room temperature  

Microsoft Academic Search

In this paper we present the first results of thin film transistors produced completely at room temperature using ZnO as the active channel and silicon oxynitride as the gate dielectric. The ZnO-based thin film transistors (ZnO-TFT) present an average optical transmission (including the glass substrate) of 84% in the visible part of the spectrum. The ZnO-TFT operates in the enhancement

E. Fortunato; A. Pimentel; L. Pereira; A. Gonçalves; G. Lavareda; H. Águas; I. Ferreira; C. N. Carvalho; R. Martins

2004-01-01

245

Energy intensities and the impact of high energy prices on producing and consuming sectors in Malaysia  

Microsoft Academic Search

The increase in oil prices has put pressure on the global economy. Even economies that have a high degree of self-sufficiency\\u000a concerning oil products are experiencing rising production costs and price increases for households energy use. Therefore,\\u000a changes in energy policies are under consideration for countries highly dependent on imported energy as well as countries\\u000a with a high degree of

Henrik Klinge Jacobsen

2009-01-01

246

A comparison of granules produced by high-shear and fluidized-bed granulation methods.  

PubMed

Placebo granules were manufactured by both wet high-shear and fluidized-bed techniques. The granules were compared based on size, shape, surface morphology, and a variety of different flowability measurements. This comparison showed that granule formation and growth were different, with induction growth for high-shear granulation and steady growth for fluidized-bed granulation. Final granules from high-shear granulation were more spherical and dense compared with the irregular granules from fluidized-bed granulation. The high-shear granules demonstrated better overall flow properties. PMID:24839117

Morin, Garett; Briens, Lauren

2014-08-01

247

Analytical Validation of a Highly Quantitative, Sensitive, Accurate, and Reproducible Assay (HERmark®) for the Measurement of HER2 Total Protein and HER2 Homodimers in FFPE Breast Cancer Tumor Specimens  

PubMed Central

We report here the results of the analytical validation of assays that measure HER2 total protein (H2T) and HER2 homodimer (H2D) expression in Formalin Fixed Paraffin Embedded (FFPE) breast cancer tumors as well as cell line controls. The assays are based on the VeraTag technology platform and are commercially available through a central CAP-accredited clinical reference laboratory. The accuracy of H2T measurements spans a broad dynamic range (2-3 logs) as evaluated by comparison with cross-validating technologies. The measurement of H2T expression demonstrates a sensitivity that is approximately 7–10 times greater than conventional immunohistochemistry (IHC) (HercepTest). The HERmark assay is a quantitative assay that sensitively and reproducibly measures continuous H2T and H2D protein expression levels and therefore may have the potential to stratify patients more accurately with respect to response to HER2-targeted therapies than current methods which rely on semiquantitative protein measurements (IHC) or on indirect assessments of gene amplification (FISH). PMID:21151530

Larson, Jeffrey S.; Goodman, Laurie J.; Tan, Yuping; Defazio-Eli, Lisa; Paquet, Agnes C.; Cook, Jennifer W.; Rivera, Amber; Frankson, Kristi; Bose, Jolly; Chen, Lili; Cheung, Judy; Shi, Yining; Irwin, Sarah; Kiss, Linda D. B.; Huang, Weidong; Utter, Shannon; Sherwood, Thomas; Bates, Michael; Weidler, Jodi; Parry, Gordon; Winslow, John; Petropoulos, Christos J.; Whitcomb, Jeannette M.

2010-01-01

248

A Rubber-Modified Thermoplastic where the Morphology Produced by Phase-Separation Induced by Polymerization Disappears at High Conversions  

E-print Network

An unexpected experimental finding is reported where the primary morphology developed during polymerization-induced phase separation in a rubber-modified thermoplastic disappears at high conversions. This process was evidenced by light scattering (LS) and scanning electron microscopy (SEM) for a particular composition of solutions of polyisobutylene oligomers (PIB) in isobornylmethacrylate (IBoMA), during the free-radical polymerization of the monomer. The primary phase separation produced a dispersion of domains rich in PIB containing significant amounts of the monomer (IBoMA). Polymerization of the monomer in these domains occurred at high overall conversions producing the filling of dispersed domains with a PIBoMA-PIB blend. Under these conditions the final material had the appearance of a homogeneous blend. The process might be adapted to produce new types of rubber-modified thermoplastics where rubber particles are replaced by rubber-rich domains that do not exhibit definite boundaries. Keywords:

E. R. Soule; G. E. Elicabe; R. J. J. Williams

2013-11-21

249

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

250

Potential of hot water extraction of birch wood to produce high-purity dissolving pulp after alkaline pulping.  

PubMed

The potential of hot water extraction of birch wood to produce highly purified dissolving pulp in a subsequent soda-anthraquinone pulping process was evaluated. After intermediate extraction intensities, pulps with low xylan content (3-5%) and high cellulose yield were successfully produced. Increasing extraction intensity further decreased the xylan content in pulp. However, below a xylan content of 3%, the cellulose yield dramatically decreased. This is believed to be due to cleavage of glycosidic bonds in cellulose during severe hot water extractions, followed by peeling reactions during alkaline pulping. Addition of sodium borohydride as well as increased anthraquinone concentration in the pulping liquor increased the cellulose yield, but had no clear effects on pulp purity and viscosity. The low intrinsic viscosity of pulps produced after severe extraction intensities and soda-anthraquinone pulping corresponded to the viscosity at the leveling-off degree of polymerization, suggesting that nearly all amorphous cellulose had been degraded. PMID:23260272

Borrega, Marc; Tolonen, Lasse K; Bardot, Fanny; Testova, Lidia; Sixta, Herbert

2013-05-01

251

Highly Flexible Dye-sensitized Solar Cells Produced by Sewing Textile Electrodes on Cloth  

PubMed Central

Textile forms of solar cells possess special advantages over other types of solar cells, including their light weight, high flexibility, and mechanical robustness. Recent demand for wearable devices has promoted interest in the development of high-efficiency textile-based solar cells for energy suppliers. However, the weaving process occurs under high-friction, high-tension conditions that are not conducive to coated solar-cell active layers or electrodes deposited on the wire or strings. Therefore, a new approach is needed for the development of textile-based solar cells suitable for woven fabrics for wide-range application. In this report, we present a highly flexible, efficient DSSC, fabricated by sewing textile-structured electrodes onto casual fabrics such as cotton, silk, and felt, or paper, thereby forming core integrated DSSC structures with high energy-conversion efficiency (~5.8%). The fabricated textile-based DSSC devices showed high flexibility and high performance under 4-mm radius of curvature over thousands of deformation cycles. Considering the vast number of textile types, our textile-based DSSC devices offer a huge range of applications, including transparent, stretchable, wearable devices. PMID:24957920

Yun, Min Ju; Cha, Seung I.; Seo, Seon Hee; Lee, Dong Y.

2014-01-01

252

Highly flexible dye-sensitized solar cells produced by sewing textile electrodes on cloth.  

PubMed

Textile forms of solar cells possess special advantages over other types of solar cells, including their light weight, high flexibility, and mechanical robustness. Recent demand for wearable devices has promoted interest in the development of high-efficiency textile-based solar cells for energy suppliers. However, the weaving process occurs under high-friction, high-tension conditions that are not conducive to coated solar-cell active layers or electrodes deposited on the wire or strings. Therefore, a new approach is needed for the development of textile-based solar cells suitable for woven fabrics for wide-range application. In this report, we present a highly flexible, efficient DSSC, fabricated by sewing textile-structured electrodes onto casual fabrics such as cotton, silk, and felt, or paper, thereby forming core integrated DSSC structures with high energy-conversion efficiency (~5.8%). The fabricated textile-based DSSC devices showed high flexibility and high performance under 4-mm radius of curvature over thousands of deformation cycles. Considering the vast number of textile types, our textile-based DSSC devices offer a huge range of applications, including transparent, stretchable, wearable devices. PMID:24957920

Yun, Min Ju; Cha, Seung I; Seo, Seon Hee; Lee, Dong Y

2014-01-01

253

ATTEMPTS TO REPRODUCE RHEUMATIC FEVER IN ANIMALS  

PubMed Central

Experiments have been described in which we attempted to reproduce in animals the lesions characteristic of rheumatic fever in the human. A large number of animals representing 7 species was employed. Among other materials, streptococci isolated in pure culture from the blood of rheumatic patients (proved to be so by biopsy or by autopsy) as well as whole blood, plasma, serum, pericardial, pleural and hydrocele fluid, filtrates from tonsils, subcutaneous nodules, lymph nodes, and nasopharyngeal washings obtained from such patients were used in a variety of combinations and with a number of procedures calculated to predispose the animal to the disease. A discussion is given of the criteria whose fulfillment is essential for the establishment of the experimental production of rheumatic disease in animals. Judged by these criteria, we have failed to reproduce the disease. This conclusion, we believe, holds true for all the work thus far reported in the literature. PMID:19869605

Gross, Louis; Loewe, Leo; Eliasoph, Benjamin

1929-01-01

254

A meshfree unification: reproducing kernel peridynamics  

NASA Astrophysics Data System (ADS)

This paper is the first investigation establishing the link between the meshfree state-based peridynamics method and other meshfree methods, in particular with the moving least squares reproducing kernel particle method (RKPM). It is concluded that the discretization of state-based peridynamics leads directly to an approximation of the derivatives that can be obtained from RKPM. However, state-based peridynamics obtains the same result at a significantly lower computational cost which motivates its use in large-scale computations. In light of the findings of this study, an update to the method is proposed such that the limitations regarding application of boundary conditions and the use of non-uniform grids are corrected by using the reproducing kernel approximation.

Bessa, M. A.; Foster, J. T.; Belytschko, T.; Liu, Wing Kam

2014-06-01

255

Dosimetric Algorithm to Reproduce Isodose Curves Obtained from a LINAC  

PubMed Central

In this work isodose curves are obtained by the use of a new dosimetric algorithm using numerical data from percentage depth dose (PDD) and the maximum absorbed dose profile, calculated by Monte Carlo in a 18?MV LINAC. The software allows reproducing the absorbed dose percentage in the whole irradiated volume quickly and with a good approximation. To validate results an 18?MV LINAC with a whole geometry and a water phantom were constructed. On this construction, the distinct simulations were processed by the MCNPX code and then obtained the PDD and profiles for the whole depths of the radiation beam. The results data were used by the code to produce the dose percentages in any point of the irradiated volume. The absorbed dose for any voxel's size was also reproduced at any point of the irradiated volume, even when the voxels are considered to be of a pixel's size. The dosimetric algorithm is able to reproduce the absorbed dose induced by a radiation beam over a water phantom, considering PDD and profiles, whose maximum percent value is in the build-up region. Calculation time for the algorithm is only a few seconds, compared with the days taken when it is carried out by Monte Carlo. PMID:25045398

Estrada Espinosa, Julio Cesar; Martinez Ovalle, Segundo Agustin; Pereira Benavides, Cinthia Kotzian

2014-01-01

256

Organic salt-assisted liquid-phase exfoliation of graphite to produce high-quality graphene  

NASA Astrophysics Data System (ADS)

Certain ordinary organic salts, such as edetate disodium, sodium tartrate, potassium sodium tartrate and sodium citrate were found to have universal and efficient assistant effect for liquid-phase exfoliation of graphite in common organic solvents to produce pristine graphene. Up to 123 times enhanced exfoliation efficiency was observed when sodium citrate was introduced into an exfoliation system consisting of natural graphite powder and dimethyl sulfoxide. TEM, AFM, Raman spectroscopy, EDX, TGA, and FTIR analysis showed graphite was successfully exfoliated into single or few-layer graphene nanosheets which were free of defects and oxides. The method is simple, effective, safe and economical.

Du, Wencheng; Lu, Jie; Sun, Peipei; Zhu, Yinyan; Jiang, Xiaoqing

2013-05-01

257

Theoretical modeling of chemical generators producing O2(1Delta) at high pressure for chemically pumped iodine lasers  

Microsoft Academic Search

A theoretical model is developed for chemical generators producing O2(1Delta) at high pressure. The model treats different types of generators, e.g., bubble-column, film, aerosol, and jet generators. The main factor affecting the O2(1Delta) yield under high pressure is liquid-phase quenching enhanced by depletion of HO2(-) ions near the gas\\/liquid interface. Simple analytical expressions are derived for the O2(1Delta) yield at

B. D. Barmashenko; S. Rosenwaks

1993-01-01

258

High frequency sounds produced by Cyprian honeybees Apis mellifera cypria when confronting their predator, the Oriental hornet Vespa orientalis  

Microsoft Academic Search

Honeybees face several predators and their ability to express collective defence behaviour is one of their major life traits that promote colony survival. We discovered that, while confronting attacks by the Oriental hornet Vespa orientalis, Apis mellifera cypria honeybees engage in a distinct acoustic behaviour: they produce a characteristic hissing sound of unexpectedly high frequency. When recording and analysing these

Alexandros Papachristoforou; Jérôme Sueur; Agnès Rortais; Sotirios Angelopoulos; Andreas Thrasyvoulou; Gérard Arnold

2008-01-01

259

High beta capture and mirror confinement of laser produced plasmas. Semiannual report, July 1, 1975January 31, 1976  

Microsoft Academic Search

The Laser Initiated Target Experiment (LITE) at the United Technologies Research Center is designed to address the target plasma buildup approach to a steady state mirror fusion device. A dense, mirror confined, target plasma is produced by high power laser irradiation of a solid lithium hydride particle, electrically suspended in a vacuum at the center of an established minimum-B magnetic

A. F. Haught; D. H. Polk; W. J. Fader; R. G. Tomlinson; R. A. Jong; W. B. Ard; A. E. Mensing; T. L. Churchill; J. H. Stufflebeam; F. J. Bresnock

1976-01-01

260

Effect of Stress Producing Situations on Manipulative Performance of High and Low Test-Anxious Industrial Arts Students.  

ERIC Educational Resources Information Center

To determine the effect which stress producing situations have upon the performance of a manipulative task by high and low test-anxious subjects, 120 seventh grade boys in general industrial arts shop class were administered the "Test Anxiety Scale for Children" and the "Lie Scale for Children." On the basis of their scores, 60 boys were selected…

Holm, Melvin G.

261

A SPRAY REACTOR CONCEPT FOR CATALYTIC OXIDATION OF P-XYLENE TO PRODUCE HIGH-PURITY TEREPHTHALIC ACID  

E-print Network

-xylene (pX) and the catalyst (Co/Mn/Br), is dispersed as fine droplets by a nozzle into a continuous vapor phase containing the oxidant (O2) is shown to produce high-purity TPA with less than 25 ppm 4-carboxybenzaldehyde (4-CBA) in the solid TPA product...

LI, MENG

2013-08-31

262

Cellulolytic and Xylanolytic Potential of High ?-Glucosidase-Producing Trichoderma from Decaying Biomass.  

PubMed

Availability, cost, and efficiency of microbial enzymes for lignocellulose bioconversion are central to sustainable biomass ethanol technology. Fungi enriched from decaying biomass and surface soil mixture displayed an array of strong cellulolytic and xylanolytic activities. Strains SG2 and SG4 produced a promising array of cellulolytic and xylanolytic enzymes including ?-glucosidase, usually low in cultures of Trichoderma species. Nucleotide sequence analysis of internal transcribed spacer 2 (ITS2) region of rRNA gene revealed that strains SG2 and SG4 are closely related to Trichoderma inhamatum, Trichoderma piluliferum, and Trichoderma aureoviride. Trichoderma sp. SG2 crude culture supernatant correspondingly displayed as much as 9.84?±?1.12, 48.02?±?2.53, and 30.10?±?1.11 units mL(-1) of cellulase, xylanase, and ?-glucosidase in 30 min assay. Ten times dilution of culture supernatant of strain SG2 revealed that total activities were about 5.34, 8.45, and 2.05 orders of magnitude higher than observed in crude culture filtrate for cellulase, xylanase, and ?-glucosidase, respectively, indicating that more enzymes are present to contact with substrates in biomass saccharification. In parallel experiments, Trichoderma species SG2 and SG4 produced more ?-glucosidase than the industrial strain Trichoderma reesei RUT-C30. Results indicate that strains SG2 and SG4 have potential for low cost in-house production of primary lignocellulose-hydrolyzing enzymes for production of biomass saccharides and biofuel in the field. PMID:25129039

Okeke, Benedict C

2014-10-01

263

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

264

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

265

Identical probes on different high-density oligonucleotide microarrays can produce different measurements of gene expression  

PubMed Central

Background There are many potential sources of variability in a microarray experiment. Variation can arise from many aspects of the collection and processing of samples for gene expression analysis. Oligonucleotide-based arrays are thought to minimize one source of variability as identical oligonucleotides are expected to recognize the same transcripts during hybridization. Results We demonstrate that although the probes on the U133A GeneChip arrays are identical in sequence to probes designed for the U133 Plus 2.0 arrays the values obtained from an experimental hybridization can be quite different. Nearly half of the probesets in common between the two array types can produce slightly different values from the same sample. Nearly 70% of the individual probes in these probesets produced array specific differences. Conclusion The context of the probe may also contribute some bias to the final measured value of gene expression. At a minimum, this should add an extra level of caution when considering the direct comparison of experiments performed in two microarray formats. More importantly, this suggests that it may not be possible to know which value is the most accurate representation of a biological sample when comparing two formats. PMID:16776839

Zhang, LanMin; Yoder, Sean J; Enkemann, Steven A

2006-01-01

266

Observation of Dust Stream Formation Produced by Low Current, High Voltage Cathode Spots  

NASA Technical Reports Server (NTRS)

Macro-particle acceleration driven by low current, high voltage cathode spots has been investigated. The phenomenon was observed to occur when nanometer and micrometer-sized particles in the presence of a discharge plasma were exposed to a high voltage pulse. The negative voltage pulse initiates the formation of multiple, high voltage, low current cathode spots which provides the mechanism of actual acceleration of the charged dust particles. Dust streams generated by this process were detected using laser scattering techniques. The particle impact craters observed at the surface of downstream witness badges were documented using SEM and light microscopy.

Foster, John E.

2004-01-01

267

Planar heterojunction perovskite solar cells with superior reproducibility  

PubMed Central

Perovskite solar cells (PeSCs) have been considered one of the competitive next generation power sources. To date, light-to-electric conversion efficiencies have rapidly increased to over 10%, and further improvements are expected. However, the poor device reproducibility of PeSCs ascribed to their inhomogeneously covered film morphology has hindered their practical application. Here, we demonstrate high-performance PeSCs with superior reproducibility by introducing small amounts of N-cyclohexyl-2-pyrrolidone (CHP) as a morphology controller into N,N-dimethylformamide (DMF). As a result, highly homogeneous film morphology, similar to that achieved by vacuum-deposition methods, as well as a high PCE of 10% and an extremely small performance deviation within 0.14% were achieved. This study represents a method for realizing efficient and reproducible planar heterojunction (PHJ) PeSCs through morphology control, taking a major step forward in the low-cost and rapid production of PeSCs by solving one of the biggest problems of PHJ perovskite photovoltaic technology through a facile method. PMID:25377945

Jeon, Ye-Jin; Lee, Sehyun; Kang, Rira; Kim, Jueng-Eun; Yeo, Jun-Seok; Lee, Seung-Hoon; Kim, Seok-Soon; Yun, Jin-Mun; Kim, Dong-Yu

2014-01-01

268

Planar heterojunction perovskite solar cells with superior reproducibility.  

PubMed

Perovskite solar cells (PeSCs) have been considered one of the competitive next generation power sources. To date, light-to-electric conversion efficiencies have rapidly increased to over 10%, and further improvements are expected. However, the poor device reproducibility of PeSCs ascribed to their inhomogeneously covered film morphology has hindered their practical application. Here, we demonstrate high-performance PeSCs with superior reproducibility by introducing small amounts of N-cyclohexyl-2-pyrrolidone (CHP) as a morphology controller into N,N-dimethylformamide (DMF). As a result, highly homogeneous film morphology, similar to that achieved by vacuum-deposition methods, as well as a high PCE of 10% and an extremely small performance deviation within 0.14% were achieved. This study represents a method for realizing efficient and reproducible planar heterojunction (PHJ) PeSCs through morphology control, taking a major step forward in the low-cost and rapid production of PeSCs by solving one of the biggest problems of PHJ perovskite photovoltaic technology through a facile method. PMID:25377945

Jeon, Ye-Jin; Lee, Sehyun; Kang, Rira; Kim, Jueng-Eun; Yeo, Jun-Seok; Lee, Seung-Hoon; Kim, Seok-Soon; Yun, Jin-Mun; Kim, Dong-Yu

2014-01-01

269

A simple method to produce almost perfect graphene on highly oriented pyrolytic graphite  

Microsoft Academic Search

A simple and effective stepwise-method has been developed to remove defects from the top graphene layers of highly orientated pyrolytic graphite. Using a combination of ozone exposure and moderately high temperature we have shown that a defect-rich graphite surface can be modified to generate a graphene-like surface containing a negligible amount of oxygen, hydrogen and sp3 carbon. We report definitive

M. J. Webb; P. Palmgren; P. Pal; O. Karis; H. Grennberg

2011-01-01

270

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

271

Experimental Measurements of a High-Energy Pseudospark-Produced Electron Beam  

NASA Astrophysics Data System (ADS)

This paper presents the progress thus far in the investigation of pseudospark-produced electron beams for medical applications. A twenty-six-gap pseudospark device is fabricated with different insulators and tested as the electron beam source. The discharge capacitor between the anode and cathode to store electrical energy is incorporated into the stacked ring design to minimize inductance. The system is operated at 100kV. Two Rogowski coils are positioned in the hole of anode flange and external capacitors to measure the total beam and discharge currents. Further, a small Langmuir probe and a Faraday cup are used to determine the energy of the beam through the comparison of the time that the e-beam passes them. Results of the scaling study for the electron beam current with breakdown voltage, gas pressure, external capacitance, and the effect of insulator material on pseudospark operating characteristics are presented.

Hu, Jing; Rovey, Joshua L.; Kovaleski, Scott

2009-11-01

272

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

273

A Process for Producing Highly Wettable Aluminum 6061 Surfaces Compatible with Hydrazine  

NASA Technical Reports Server (NTRS)

NASA's Global Precipitation Measurement (GPM) mission is an ongoing Goddard Space Flight Center (GSFC) project whose basic objective is to improve global precipitation measurements. The space-based portion of the mission architecture consists of a primary or core spacecraft and a constellation of NASA and contributed spacecrafts. The efforts described in this paper refer to the core spacecraft (hereafter referred to as simply GPM) which is to be fabricated at GSFC. It has been decided that the GPM spacecraft is to be a "design-for-demise-spacecraft." This requirement resulted in the need for a propellant tank that would also demise or ablate to an appropriate degree upon re-entry. Composite overwrapped aluminum lined propellant tanks with aluminum propellant management devices (PMD) were shown by analyses to demise and thus became the baseline configuration for GPM. As part of the GPM tank development effort, long term compatibility and wettability testing with hydrazine was performed on Al6061 and 2219 coupons fabricated and cleaned by conventional processes. Long term compatibility was confirmed. However, the wettability of the aluminum as measured by contact angle produced higher than desired angles (greater than 30 deg.) with excessive scatter. The availability of PMD materials exhibiting consistently low contact angles aids in the design of simple PMDs. Two efforts performed by Angeles Crest Engineering and funded by GSFC were undertaken to reduce the risk of using aluminum for the GPM PMD. The goal of the first effort was to develop a cleaning or treatment process to produce consistently low contact angles. The goal of the second effort was to prove via testing that the processed aluminum would retain compatibility with hydrazine and retain low contact angle after long term exposure to hydrazine. Both goals were achieved. This paper describes both efforts and the results achieved.

Moore, N. R.; Ferraro, N. W.; Yue, A. F.; Estes, R. H.

2007-01-01

274

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

275

High Rate of Fecal Carriage of Extended-Spectrum-?-Lactamase-Producing Escherichia coli in Healthy Children in Gipuzkoa, Northern Spain  

PubMed Central

The prevalence of extended-spectrum-?-lactamase-producing Enterobacteriaceae (ESBLPE) was studied in stool samples from 125 8- to 16-month-old healthy children. Twenty-four percent of them and 10.7% of the 318 fecal samples studied yielded extended-spectrum-?-lactamase-producing Escherichia coli, with the types being SHV-12, CTX-M-1, CTX-M-14, and TEM-52, the most common types of ?-lactamases. This high prevalence of ESBLPE in healthy people, which is to our knowledge the highest currently reported in Europe, may represent a risk for increased infections by these organisms in the future. PMID:24395224

Fernandez-Reyes, Maria; Vicente, Diego; Gomariz, Maria; Esnal, Olatz; Landa, Joseba; Onate, Eider

2014-01-01

276

A review of research and methods for producing high-consequence software  

SciTech Connect

The development of software for use in high-consequence systems mandates rigorous (formal) processes, methods, and techniques to improve the safety characteristics of those systems. This paper provides a brief overview of current research and practices in high-consequence software, including applied design methods. Some of the practices that are discussed include: fault tree analysis, failure mode effects analysis, petri nets, both hardware and software interlocks, n-version programming, Independent Vulnerability Analyses, and watchdogs. Techniques that offer improvement in the dependability of software in high-consequence systems applications are identified and discussed. Limitations of these techniques are also explored. Research in formal methods, the cleanroom process, and reliability models are reviewed. In addition, current work by several leading researchers as well as approaches being used by leading practitioners are examined.

Collins, E.; Dalton, L.; Peercy, D.; Pollock, G.; Sicking, C.

1994-12-31

277

Studies of Light and Charge Produced by Alpha-Particles in High-Pressure Xenon  

NASA Technical Reports Server (NTRS)

The results of measurements of scintillation light induced by alpha-particles in high-pressure Xe are presented. The ratio of N(sub ex)/N(sub i) and the intensity and time characteristics of the luminescence signal have been measured for different densities up to 0.74 g/cc. The role and mechanisms of the electron-ion recombination in high-pressure gas have been investigated. The existence of clusters and self-trapped excitons above 0.6 g/cc has been observed and discussed. This work is a part of a development program of high-pressure Xe detectors for low-energy gamma rays.

Bolotnikov, Aleksey; Ramsey, Brian

1999-01-01

278

Producing - Harvesting - Marketing High Quality Upland Cotton in the El Paso Trade Territory.  

E-print Network

accurately. Use con- pon and 1 pound of detergent in 5 gallons of water for knapsack-type sprayers ; use some- what less concentrated mixture for power sprayers. Begin early when grass is not more than 6 to 8 inches high and respray at 10 to 14-day... accurately. Use con- pon and 1 pound of detergent in 5 gallons of water for knapsack-type sprayers ; use some- what less concentrated mixture for power sprayers. Begin early when grass is not more than 6 to 8 inches high and respray at 10 to 14-day...

Taylor, Charles A. (compiler)

1963-01-01

279

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

280

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. 16 figs.

Morris, D.E.

1996-02-20

281

Potential of producing hydrogen and high Btu gas from steam gasification of lignins  

SciTech Connect

Generally, lignins are considered as a waste product from the pulp and paper industry. In this work, the authors have attempted to convert a number of lignins to hydrogen and high Btu gas by gasifying them with steam. Steam gasification of three lignins, namely, Kraft-1, Kraft-2 and Alcell was carried out in a fixed bed reactor in the temperature range 600--800 C. The steam flow rate was 10 g/h/g of lignin. As expected, lignin conversion was highest at 800 C and followed the order Kraft-1 {gt} Kraft-2 {gt} Alcell. The product gas consisted of H{sub 2}, CO, CO{sub 2}, and CH{sub 4}, C{sub 2} and C{sub 3+} hydrocarbons. The Btu value of the product gas ranged between 450--850 Btu/scf. It was interesting to observe that the H{sub 2} content was fairly high and ranged between 30--50 mol% of the product gas mixture. In addition, the effect of steam flow rate (5--15 g/h/g of lignin) was also studied at a fixed temperature of 800 C. It was interesting to observe that at high steam flow rates, the lignin conversion increased and the process resulted in high selectivity for CH{sub 4}. All these three lignins have been thoroughly characterized. A comparison of these results with results obtained from steam gasification of biomass-derived chars will also be presented.

Iqbal, M.; Dalai, A.K.; Bakhshi, N.N.; Thring, R.W.

1998-07-01

282

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

283

Selection of psychrotrophic Leuconostoc spp. producing highly active dextransucrase from lactate fermented vegetables  

Microsoft Academic Search

Leuconostoc is the major bacterial genus in the initial phase of the lactate fermentation of vegetables. The dextransucrase elaborated from this bacterium is used to synthesize dextran polymers or prebiotic oligosaccharides. To use Leuconostoc as a starter culture in the manufacture of the kimchi-like fermented foods at low temperature, we isolated microbial flora that showed fast growth rates and high

Hyun-Ju Eom; Dong Mi Seo; Nam Soo Han

2007-01-01

284

Generation and Propagation of High Quality Proton Beams Produced by Laser Plasma Interactions  

Microsoft Academic Search

The acceleration of proton beams during the interaction of an ultra short and ultra intense laser pulse with matter is possibly the most important application of compact laser systems with multi-terawatt and petawatt power. High quality beams with a small energy spread are required for applications where spatially accurate energy deposition is important. For some specific applications the target may

F. Pegoraro; S. V. Bulanov; F. Califano; T. Zh. Esirkepov

2004-01-01

285

Development of a Germination Process for Producing High ?-Glucan, Whole Grain Food Ingredients from Oat  

Microsoft Academic Search

Cereal Chem. 78(6):715-720 Germination can be used to improve the texture and flavor of cereals. However, germination generally causes breakdown of ?-glucans, which is undesirable with respect to the functional properties of ?-glucan. Our aim was to assess possibilities of germinating oat without substantial loss of high molecular weight ?-glucan. Two cultivars, hulled Veli and hull- less (naked) Lisbeth were

A. Wilhelmson; K.-M. Oksman-Caldentey; A. Laitila; T. Suortti; A. Kaukovirta-Norja; K. Poutanen

2001-01-01

286

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

287

Pressure stabilizer for reproducible picoinjection in droplet microfluidic systems.  

PubMed

Picoinjection is a promising technique to add reagents into pre-formed emulsion droplets on chip however, it is sensitive to pressure fluctuation, making stable operation of the picoinjector challenging. We present a chip architecture using a simple pressure stabilizer for consistent and highly reproducible picoinjection in multi-step biochemical assays with droplets. Incorporation of the stabilizer immediately upstream of a picoinjector or a combination of injectors greatly reduces pressure fluctuations enabling reproducible and effective picoinjection in systems where the pressure varies actively during operation. We demonstrate the effectiveness of the pressure stabilizer for an integrated platform for on-demand encapsulation of bacterial cells followed by picoinjection of reagents for lysing the encapsulated cells. The pressure stabilizer was also used for picoinjection of multiple displacement amplification (MDA) reagents to achieve genomic DNA amplification of lysed bacterial cells. PMID:25270338

Rhee, Minsoung; Light, Yooli K; Yilmaz, Suzan; Adams, Paul D; Saxena, Deepak; Meagher, Robert J; Singh, Anup K

2014-12-01

288

Stressed mothers lay eggs with high corticosterone levels which produce low-quality offspring.  

PubMed

Organisms frequently encounter stressful ecological conditions. In vertebrates, a major mechanism of physiological response to stress is mediated by the hypothalamic-pituitary-adrenal axis and results in increased secretion of glucocorticosteroids, which can have adverse consequences on diverse phenotypic traits affecting fitness. Maternal stress may thus have carry-over effects on progeny if it influences pre-natal offspring environment in terms of glucocorticosteroid concentration, although this hypothesis has never been tested in any species under field conditions. We manipulated stress experienced by female barn swallows Hirundo rustica, by exposing them to a predator during laying and measured egg corticosterone concentration. Stressed females laid eggs with greater corticosterone concentration than controls exposed to a herbivore. In another experiment, we injected physiological doses of corticosterone in the egg albumen and compared the phenotype of offspring originating from these eggs with their control siblings originating from either sham-inoculated or unmanipulated eggs and reared in the same nest. Eggs injected with corticosterone had lower hatchability and produced fledglings with smaller body size and slower plumage development than did control eggs. Nestling body size in our study population predicts long-term survival. Thus, maternal stress impaired offspring phenotype and viability by increasing transmission of glucocorticosteroids to the eggs. This study identifies a novel mechanism mediating early maternal effects whereby maternal stress affects offspring quality. These results are relevant to biological conservation because they disclose a mechanism that can link environmental conditions to population productivity and viability. PMID:16217808

Saino, Nicola; Romano, Maria; Ferrari, Raffaella Paola; Martinelli, Roberta; Møller, Anders Pape

2005-11-01

289

Increasing gas hydrate formation temperature for desalination of high salinity produced water with secondary guests  

SciTech Connect

We suggest a new gas hydrate-based desalination process using water-immiscible hydrate formers; cyclopentane (CP) and cyclohexane (CH) as secondary hydrate guests to alleviate temperature requirements for hydrate formation. The hydrate formation reactions were carried out in an isobaric condition of 3.1 MPa to find the upper temperature limit of CO2 hydrate formation. Simulated produced water (8.95 wt % salinity) mixed with the hydrate formers shows an increased upper temperature limit from ?2 °C for simple CO2 hydrate to 16 and 7 °C for double (CO2 + CP) and (CO2 + CH) hydrates, respectively. The resulting conversion rate to double hydrate turned out to be similar to that with simple CO2 hydrate at the upper temperature limit. Hydrate formation rates (Rf) for the double hydrates with CP and CH are shown to be 22 and 16 times higher, respectively, than that of the simple CO2 hydrate at the upper temperature limit. Such mild hydrate formation temperature and fast formation kinetics indicate increased energy efficiency of the double hydrate system for the desalination process. Dissociated water from the hydrates shows greater than 90% salt removal efficiency for the hydrates with the secondary guests, which is also improved from about 70% salt removal efficiency for the simple hydrates.

Cha, Jong-Ho [ORISE; Seol, Yongkoo [U.S. DOE

2013-01-01

290

Producing hollow granules from hydrophobic powders in high-shear mixer granulators  

Microsoft Academic Search

The formation of hollow granules from hydrophobic powders in a high-shear mixer granulator has been investigated by changing the binder\\/powder mass ratio and studying its effects on granule size and structure. In this study, a mixer granulator was filled with 100g of hydrophobic fumed silica and then varying quantities of 5% Hydroxy Propyl Cellulose solution was slowly sprayed into granulator.

Nicky Eshtiaghi; Benedicta Arhatari; Karen P. Hapgood

2009-01-01

291

A study of high transverse momentum electrons produced inbar pp collisions at 540 GeV  

Microsoft Academic Search

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

P. Bagnaia; M. Banner; R. Battiston; Ph. Bloch; Franco Bonaudi; K. Borer; Michel Borghini; J. Burger; P. Cenci; J.-C. Chollet; A. G. Clark; C. Conta; Pierre Darriulat; L. di Lella; J. Dines-Hansch; P. A. Dorsaz; R. Engelmann; Louis Fayard; M. Fraternali; Daniel Froidevaux; G. Fumagalli; Jean-Marc Gaillard; O. Gildemeister; V. G. Goggi; C. Gössling; B. Hahn; H. Hänni; J. R. Hansen; P. Hansen; N. Harnew; Thomas M Himel; V. Hungerbühler; Peter Jenni; Otto Møgens Kofoed-Hansen; E. Lançon; M. Livan; Sotirios S Loucatos; B. Madsen; P. Mani; B. Mansoulié; G. C. Mantovani; Livio P Mapelli; B. Merkel; R. Möllerud; B. Nilsson; Christopher J Onions; G. Parrour; F. Pastore; Hartmute Plothow-Besch; M. Polverel; J.-P. Repellin; A. Rimoldi; A F Rothenberg; A. Roussarie; G. Sauvage; J. Schacher; J. L. Siegrist; G. Stimpfl; F. Stocker; M. Swartz; J. Teiger; Stuart N Tovey; V. Vercesi; W. R. Weidberg; Henri Zaccone; J. A. Zakrzewski; W. Zeller

1984-01-01

292

High-power splitting of expanded graphite to produce few-layer graphene sheets  

Microsoft Academic Search

Few-layer graphene sheets were prepared by splitting expanded graphite using high-power sonication. Atomic-level calibrated scanning transmission electron microscopy was used to obtain efficient layer statistics, enabling optimization of the experimental conditions. This resulted in a two-step splitting mechanism in which the mean number of layers was first reduced to less than 20 by heating to 1100°C and then to a

Kaiming Liao; Wangfeng Ding; Bo Zhao; Zhaoguo Li; Fengqi Song; Yuyuan Qin; Taishi Chen; Jianguo Wan; Min Han; Guanghou Wang; Jianfeng Zhou

2011-01-01

293

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

294

A high-resolution coherent transition radiation diagnostic for laser-produced electron transport studies (invited).  

PubMed

High-resolution images of the rear-surface optical emission from high-intensity (I approximately 10(19) W/cm(2)) laser illuminated metal foils have been recorded using coherent transition radiation (CTR). CTR is generated as relativistic electrons, generated in high-intensity laser-plasma interactions, exit the target's rear surface and move into vacuum. A transition radiation diagnostic (TRD) records time-integrated images in a 24 nm bandwidth window around lambda=529 nm. The optical transmission at lambda=1053 nm, the laser wavelength, is 15 orders of magnitude lower than the transmission at the wavelength of interest, lambda=527 nm. The detector is a scientific grade charge-coupled device (CCD) camera that operates with a signal-to-noise ratio of 10(3) and has a dynamic range of 10(4). The TRD has demonstrated a spatial resolution of 1.4 microm over a 1 mm field of view, limited only by the CCD pixel size. PMID:19044648

Storm, M; Begishev, I A; Brown, R J; Guo, C; Meyerhofer, D D; Mileham, C; Myatt, J F; Nilson, P M; Sangster, T C; Stoeckl, C; Theobald, W; Zuegel, J D

2008-10-01

295

Producing high sugar concentrations from loblolly pine using wet explosion pretreatment.  

PubMed

We present quantitative analysis of pretreatment for obtaining high conversion and release of sugars from loblolly pine. We use wet explosion (WEx): wet oxidation followed by steam explosion and enzymatic hydrolysis (EH) at high dry matter to solubilize sugars. WEx was conducted at 25% (w/w) solids in presence of oxygen at pressures 6.5-7.2 bar, temperatures 170-175°C and residence time from 20 to 22.5 min. EH of pretreated samples was performed by Cellic® Ctec2 (60 mg protein/g cellulose) and Cellic® Htec2 enzymes (10% of Ctec2) at 50°C for 72 h. At the optimal WEx condition 96% cellulose and nearly 100% hemicellulose yield were obtained. The final concentrations of monomeric sugars were 152 g/L of glucose, 67 g/L of xylose, and 67 g/L of minor sugars (galactose, arabinose and mannose). Compared to previous work WEx seems to be superior for releasing high concentrations of monomeric sugars. PMID:22854131

Rana, Diwakar; Rana, Vandana; Ahring, Birgitte K

2012-10-01

296

Test-Retest Reproducibility Analysis of Lung CT Image Features.  

PubMed

Quantitative size, shape, and texture features derived from computed tomographic (CT) images may be useful as predictive, prognostic, or response biomarkers in non-small cell lung cancer (NSCLC). However, to be useful, such features must be reproducible, non-redundant, and have a large dynamic range. We developed a set of quantitative three-dimensional (3D) features to describe segmented tumors and evaluated their reproducibility to select features with high potential to have prognostic utility. Thirty-two patients with NSCLC were subjected to unenhanced thoracic CT scans acquired within 15 min of each other under an approved protocol. Primary lung cancer lesions were segmented using semi-automatic 3D region growing algorithms. Following segmentation, 219 quantitative 3D features were extracted from each lesion, corresponding to size, shape, and texture, including features in transformed spaces (laws, wavelets). The most informative features were selected using the concordance correlation coefficient across test-retest, the biological range and a feature independence measure. There were 66 (30.14 %) features with concordance correlation coefficient???0.90 across test-retest and acceptable dynamic range. Of these, 42 features were non-redundant after grouping features with R (2) Bet???0.95. These reproducible features were found to be predictive of radiological prognosis. The area under the curve (AUC) was 91 % for a size-based feature and 92 % for the texture features (runlength, laws). We tested the ability of image features to predict a radiological prognostic score on an independent NSCLC (39 adenocarcinoma) samples, the AUC for texture features (runlength emphasis, energy) was 0.84 while the conventional size-based features (volume, longest diameter) was 0.80. Test-retest and correlation analyses have identified non-redundant CT image features with both high intra-patient reproducibility and inter-patient biological range. Thus making the case that quantitative image features are informative and prognostic biomarkers for NSCLC. PMID:24990346

Balagurunathan, Yoganand; Kumar, Virendra; Gu, Yuhua; Kim, Jongphil; Wang, Hua; Liu, Ying; Goldgof, Dmitry B; Hall, Lawrence O; Korn, Rene; Zhao, Binsheng; Schwartz, Lawrence H; Basu, Satrajit; Eschrich, Steven; Gatenby, Robert A; Gillies, Robert J

2014-12-01

297

Contributions to reproducible CPV outdoor power ratings  

NASA Astrophysics Data System (ADS)

Methodologies that aim to obtain a reproducible power rating are still under discussion at the WG7 of the IEC and there is a need for feedback from real field application in order to validate or improve these methods. These procedures are evaluated through the outdoor rating of seven modules from four different CPV technologies, which have been measured at the CEA outdoor monitoring bench at the Institut National de l'Energie Solaire (INES) site. The benefit of introducing other procedural considerations is analyzed, namely the inclusion of spectrally-corrected irradiance, the utilization of lens temperature as a new parameter for regressions and the optimization of dataset filtering.

Besson, Pierre; Domínguez, César; Baudrit, Mathieu

2014-09-01

298

A tetracycline-regulated cell line produces high-titer lentiviral vectors that specifically target dendritic cells.  

PubMed

Lentiviral vectors (LVs) are a powerful means of delivering genetic material to many types of cells. Because of safety concerns associated with these HIV-1 derived vectors, producing large quantities of LVs is challenging. In this paper, we report a method for producing high titers of self-inactivating LVs. We retrovirally transduce the tet-off stable producer cell line GPR to generate a cell line, GPRS, which can express all the viral components, including a dendritic cell-specific glycoprotein, SVGmu. Then, we use concatemeric DNA transfection to transfect the LV transfer plasmid encoding a reporter gene GFP in combination with a selectable marker. Several of the resulting clones can produce LV at a titer 10-fold greater than what we achieve with transient transfection. Plus, these viruses efficiently transduce dendritic cells in vitro and generate a strong T cell immune response to our reporter antigen. This method may be a good option for producing strong LV-based vaccines for clinical studies of cancer or infectious diseases. PMID:23851977

Bryson, Paul D; Zhang, Chupei; Lee, Chi-Lin; Wang, Pin

2013-01-01

299

First experiment on fission transients in highly fissile spherical nuclei produced by fragmentation of radioactive beams  

E-print Network

We report on a novel experimental approach for studying the dissipative spreading of collective motion in a meta-stable nuclear system, using, for the first time, highly fissile nuclei with spherical shape. This was achieved by fragmentation of 45 radioactive heavy-ion beams at GSI, Darmstadt. The use of inverse kinematics and a dedicated experimental set-up allowed for the identification in atomic number of both fission fragments. From the width of their charge distributions, a transient time of (3.3 +/- 0.7) 10-21 s is deduced for initially spherical nuclei.

C. Schmitt; P. N. Nadtochy; A. Heinz; B. Jurado; A. Kelic; K. -H. Schmidt

2007-02-12

300

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

SciTech Connect

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.; Dangor, A.E.; Gopal, A.; Tatarakis, M.; Krushelnick, K. [Blackett Laboratory, Imperial College London SW7 2BZ (United Kingdom); Clark, E.L.; Evans, R.G. [Blackett Laboratory, Imperial College London SW7 2BZ (United Kingdom); Plasma Physics Department, AWE plc, Aldermaston, Reading RG7 4PR (United Kingdom); Ledingham, K.W.D. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Plasma Physics Department, AWE plc, Aldermaston, Reading RG7 4PR (United Kingdom); McKenna, P. [Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Norreys, P.A. [Central Laser Facility, Rutherford Appleton Laboratory, Chilton, Oxon OX11 OQX (United Kingdom); Zepf, M. [Department of Physics, The Queen's University, University Road, Belfast BT7 1NN (United Kingdom)

2004-11-01

301

High impact strength polymers having novel nano-structures produced via reactive extrusion  

NASA Astrophysics Data System (ADS)

A major focus of scientists and engineers over the last century has been to increase the impact strength and therefore reduce the brittleness of materials. By altering and adding energy absorption mechanisms, brittle failure can be averted. Isotactic polypropylene (PP) is the focus of this dissertation because it is an extremely low cost, high volume, versatile plastic but behaves in a brittle manner at or below room temperature or in a notched state. Early work on impact modification of polypropylene focused on blending energy-absorbing low density elastomers and rubbers. These binary blends all had a common problem---an increase in impact strength was paralleled by a significant decrease in both elastic modulus and yield stress. Reactive extrusion processing has allowed the in-situ compatibilization of isotactic polypropylene and metallocene-catalyzed ethylene-octene copolymers (EOCs). This process involves combining both the comonomer and vector fluid approaches to grafting polyolefins. Styrene monomer and a multifunctional acrylate monomer undergo peroxide-induced copolymerization and grafting in the presence of both PP and EOC. This results in a phase separated alloy with an impact strength over 13 times that of pure polypropylene and double that of the physical blend. There is also a significant improvement in stress-strain performance when comparing the alloys to physical blend counterparts. Many researchers have categorized the necessary components to toughening polypropylene as pertaining to the amorphous phase. The alloys described in this dissertation meet the criteria put forth by these researchers, namely low density, crystallinity, and modulus of the elastomer phase, sub-micron particle diameter, close inter-particle distance, and a high degree of entanglements of both the PP matrix phase and EOC minor phase. But many people neglect to study the crystalline state of impact modified PP in conjunction with the amorphous phase. This work shows that the typical 10-100 mum diameter spherulitic structures found in pure PP are not present in the alloys. In fact, the spherulites are less than a micron in diameter, are uniformly distributed throughout the sample, and crystallize at much higher temperatures. SEM images, when coupled with DSC and XRD, reveal the presence of a high number of small lamellar crystals composed of a unique highly dense cross-hatched structure. Thus, impact strength and stiffness can be simultaneously improved by controlling the size and cross-hatch density of the lamellar crystals and applying phase transformation toughening concepts.

Tortorella, Nathan Fraser

302

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

DOEpatents

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 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.degree.-1700.degree. 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.

Pugar, Eloise A. (Isla Vista, CA); Morgan, Peter E. D. (Thousand Oaks, CA)

1990-01-01

303

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

304

Reproducibility of Endurance Performance on a Treadmill Using a Preloaded Time Trial  

Microsoft Academic Search

RUSSELL, R. D., S. M. REDMANN, E. RAVUSSIN, G. R. HUNTER, and D. ENETTE LARSON-MEYER. Reproducibility of Endurance Performance on a Treadmill Using a Preloaded Time Trial. Med. Sci. Sports Exerc., Vol. 36, No. 4, pp. 717-724, 2004. Purpose: The purpose of this study was to establish a highly reproducible test to measure endurance performance in runners. Methods: We evaluated

RYAN D. RUSSELL; STEPHEN M. REDMANN; ERIC RAVUSSIN; GARY R. HUNTER; D. ENETTE LARSON-MEYER

2004-01-01

305

Potentiality of red sorghum for producing stilbenoid-enriched beers with high antioxidant activity.  

PubMed

trans-Piceid and trans-resveratrol were authenticated for the first time by high-resoution mass spectrometry in red sorghum grains. A 0.4-1 mg/kg amount of trans-piceid and up to 0.2 mg/kg trans-resveratrol were quantified by reversed phase high-performance liquid chromatography-atmospheric pressure chemical ionization(+)-tandem mass spectrometry. The white sorghum samples contained only traces of trans-piceid (up to 0.1 mg/kg), and trans-resveratrol was absent. In much lower amounts than procyanidins, stilbenoids are not able to contribute significantly to the exceptional antioxidant activity of red sorghum (ORAC, 83-147 ?mol TE/g; AAPH, 0.61-1.79 min/mg kg(-1)). More than 10 mg/kg of total stilbenoids have been reported in some hop varieties. Yet, as hop is a minor wort ingredient as compared to cereals, red sorghum could be the main source of trans-piceid in beer. Hop remains, however, the single source of cis-piceid. PMID:21381750

Bröhan, Meike; Jerkovic, Vesna; Collin, Sonia

2011-04-27

306

NOD macrophages produce high levels of inflammatory cytokines upon encounter of apoptotic or necrotic cells.  

PubMed

During the development of type 1 diabetes, pancreatic beta-cells are subject to an immune attack, leading to their apoptotic or necrotic cell death. Apoptotic beta-cells are also present during periods of tissue remodeling, such as in early life. Macrophages should clear apoptotic cells silently without production of pro-inflammatory cytokines. The aim of the present study was to investigate the cytokine pattern of NOD macrophages exposed to apoptotic or necrotic cells in vitro. In contrast to the limited response of macrophages from C57BL/6 or NOR mice, NOD macrophages reacted aberrantly to both necrotic and apoptotic cells, with secretion of inappropriately high amounts of IL1beta and TNFalpha. Further exploration of the macrophage behavior showed an excessive response of NOD macrophages when exposed to LPS (high iNOS and IL12p40 levels), accompanied by hyper-activation of NF-kappaB(p65). In contrast, NOD macrophages failed to up-regulate IL1beta and IL12p40 in response to IFNgamma. This failure correlated with low protein levels and a low phosphorylation state of STAT1alpha. We conclude that NOD macrophages have severely aberrant cytokine expression patterns that could contribute to the initiation or continuation of an immune attack towards the pancreatic beta-cells and thus onset and progression of type 1 diabetes. PMID:15236748

Stoffels, K; Overbergh, L; Giulietti, A; Kasran, A; Bouillon, R; Gysemans, C; Mathieu, C

2004-08-01

307

Reproducibility Data on SUMMiT  

SciTech Connect

SUMMiT (Sandia Ultra-planar Multi-level MEMS Technology) at the Sandia National Laboratories' MDL (Microelectronics Development Laboratory) is a standardized MEMS (Microelectromechanical Systems) technology that allows designers to fabricate concept prototypes. This technology provides four polysilicon layers plus three sacrificial oxide layers (with the third oxide layer being planarized) to enable fabrication of complex mechanical systems-on-a-chip. Quantified reproducibility of the SUMMiT process is important for process engineers as well as designers. Summary statistics for critical MEMS technology parameters such as film thickness, line width, and sheet resistance will be reported for the SUMMiT process. Additionally, data from Van der Pauw test structures will be presented. Data on film thickness, film uniformity and critical dimensions of etched line widths are collected from both process and monitor wafers during manufacturing using film thickness metrology tools and SEM tools. A standardized diagnostic module is included in each SWiT run to obtain post-processing parametric data to monitor run-to-run reproducibility such as Van der Pauw structures for measuring sheet resistance. This characterization of the SUMMiT process enables design for manufacturability in the SUMMiT technology.

Irwin, Lloyd; Jakubczak, Jay; Limary, Siv; McBrayer, John; Montague, Stephen; Smith, James; Sniegowski, Jeffry; Stewart, Harold; de Boer, Maarten

1999-07-16

308

High frequency sounds produced by Cyprian honeybees Apis mellifera cypria when confronting their predator, the Oriental hornet Vespa orientalis  

Microsoft Academic Search

Honeybees face several predators and their ability to express collective defence behaviour is one of their major life traits\\u000a that promote colony survival. We discovered that, while confronting attacks by the Oriental hornet Vespa orientalis, Apis mellifera cypria honeybees engage in a distinct acoustic behaviour: they produce a characteristic hissing sound of unexpectedly high frequency.\\u000a When recording and analysing these

Alexandros Papachristoforou; Jérôme Sueur; Agnès Rortais; Sotirios Angelopoulos; Andreas Thrasyvoulou; Gérard Arnold

2008-01-01

309

Purification of trans-astaxanthin from a high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis  

Microsoft Academic Search

The purification method including extraction, saponification, and separation was established for preparing free trans-astaxanthin from a high-yielding astaxanthin ester-producing strain of the microalga Haematococcus pluvialis which contained 3.67% trans-astaxanthins and 1.35% cis-astaxanthins of the dry cells. Low temperature (5°C) was chosen to minimize the degradation of astaxanthins during saponification, and 94.4% free trans-astaxanthin was obtained from trans-astaxanthin esters after 12

Jian-Ping Yuan; Feng Chen

2000-01-01

310

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

311

Isolation of a novel high erythritol-producing Pseudozyma tsukubaensis and scale-up of erythritol fermentation to industrial level  

Microsoft Academic Search

This study isolated a novel erythritol-producing yeast strain, which is capable of growth at high osmolarity. Characteristics\\u000a of the strain include asexual reproduction by multilateral budding, absence of extracellular starch-like compounds, and a\\u000a negative Diazonium blue B color reaction. Phylogenetic analysis based on the 26S rDNA sequence and physiological analysis\\u000a indicated that the strain belongs to the species Pseudozyma tsukubaensis

Marimuthu Jeya; Kyoung-Mi Lee; Manish Kumar Tiwari; Jung-Soo Kim; Paramasamy Gunasekaran; Sang-Yong Kim; In-Won Kim; Jung-Kul Lee

2009-01-01

312

High-strain-rate superplasticity at low temperature in a ZK61 magnesium alloy produced by powder metallurgy  

Microsoft Academic Search

In the present study, superplastic behavior of a pseudo single phase magnesium alloy, ZK61, was investigated at about half the absolute melting point. The material was produced by the P\\/M route, and had a fine grain size of [approximately]500 nm. It is demonstrated that the P\\/M ZK61 alloy can behave in a superplastic manner at a high strain rate of

Hiroyuki Watanabe; Toshiji Mukai; Mamoru Mabuchi; Kenji Higashi

1999-01-01

313

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

314

Comparison of bare fiber and contact diffuser tip inductions of interstitial laser lesions: assessment of reproducibility using magnetic resonance imaging  

NASA Astrophysics Data System (ADS)

Ninety interstitial lesions were produced in ex-vivo sheep liver using various power outputs (5, 10, and 20 Watts) and exposure times for delivery of 200 Joules of the Nd:YAG laser energy. For the purpose of determining lesion reproducibility, two different methods of laser energy delivery to tissue, namely, the bare fiber optic and the sapphire diffuser tip techniques, were utilized. Cross-sectional magnetic resonance imaging (MRI) or laser treated specimens were performed on a 1.5 Tesla superconducting magnet. Images were examined for shape and extent of damage, as well as uniformity. Lateral and longitudinal extent of thermal injury was measured from the image of each lesion. Results showed that the diffuser tip method is better able to reproduce lesions than the bare fiber method, particularly when high levels of laser power are employed. This study indicates the need for development of MRI-compatible diffuser tip technology for use in MRI-guided interstitial laser therapy.

Farahani, Keyvan; Castro, Dan J.; Lufkin, Robert B.

1992-06-01

315

Single-walled carbon nanotubes produced at high yield by mixed catalysts  

NASA Astrophysics Data System (ADS)

We report here on the high-density preparation of single-wall tubes in the presence of mixed catalysts of the types Fe/Ni and Co/Ni, in the soot as well as in the weblike deposits forming in the chamber. The yield is much higher than previously reported, and gram quantities can be obtained. Diameters cover the range from 0.9 to 3.1 nm, larger than previously reported, with the histogram showing only one peak at 1.7 nm. Evidence of an epitaxial action between C60 and single-walled nanotubes is presented. Results from the mixed catalysts Co/Cu, Ni/Mg, and Ni/Ti are also reported.

Seraphin, Supapan; Zhou, Dan

1994-04-01

316

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 40-60 keV and fluence from 1 × 10 11 to 5 × 10 14 ions/cm 2. 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 was 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 100 keV. The distribution of implanted ions was measured by Rutherford Backscattering Spectrometry (RBS) and calculated in theory. The mechanism of mutation induced by ion implantation was discussed.

Yu, Chen; Zhixin, Lin; Zuyao, Zou; Feng, Zhang; Duo, Liu; Xianghuai, Liu; Jianzhong, Tang; Weimin, Zhu; Bo, Huang

317

Widespread occurrence of neonicotinoid insecticides in streams in a high corn and soybean producing region, USA  

USGS Publications Warehouse

Neonicotinoid insecticides are of environmental concern, but little is known about their occurrence in surface water. An area of intense corn and soybean production in the Midwestern United States was chosen to study this issue because of the high agricultural use of neonicotinoids via both seed treatments and other forms of application. Water samples were collected from nine stream sites during the 2013 growing season. The results for the 79 water samples documented similar patterns among sites for both frequency of detection and concentration (maximum:median) with clothianidin (75%, 257 ng/L:8.2 ng/L) > thiamethoxam (47%, 185 ng/L: imidacloprid (23%, 42.7 ng/L: <2 ng/L). Neonicotinoids were detected at all nine sites sampled even though the basin areas spanned four orders of magnitude. Temporal patterns in concentrations reveal pulses of neonicotinoids associated with rainfall events during crop planting, suggesting seed treatments as their likely source.

Hladik, Michelle L.; Kolpin, Dana W.; Kuivila, Kathryn M.

2014-01-01

318

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

319

Low stream density watersheds produce flashier floods than high stream density watersheds in ephemeral streams across the southwestern United States  

NASA Astrophysics Data System (ADS)

Eighty percent of watersheds in the southwestern U.S. are ephemeral. Although flow in these watersheds only occurs immediately following rainstorms, these are dynamic systems that can be serious flood hazards. Watershed-stream density was calculated by dividing watershed area by total stream length. Flood recurrence intervals were calculated for peak and total flood volume, both seasonally and annually using 15-minute hydrograph data for 24 ephemeral watersheds in Nevada, Arizona, and New Mexico, where rainfall patterns are heavily influenced by seasonal climate. Stream density and flow statistics were compared seasonally for all watersheds. Ephemeral streams with low density (>0.7) produced larger flood peaks and volumes than their high density counterparts. Further, low stream density watershed flows mirror storm events, while high stream density watersheds mute high intensity rainfall. The opposite effect is observed in perennial watersheds, where higher density streams produce relatively the largest flood peak and volumes. This is likely because ephemeral streams can lose up to 40% of the in-channel flow to infiltration and evaporation. As the flood runoff travel length grows, the greater attenuation and infiltration results in muted flood peaks and lower flood volumes. In the study ephemeral watersheds, the low density streams are more likely to produce serious and damaging flood peaks and volumes in all seasons but especially during the summer monsoon.

Fraser, N.; Schumer, R.

2012-12-01

320

Economic effect of the highly pathogenic avian influenza H5N1 outbreaks among turkey producers, 2005-06, Turkey.  

PubMed

This research assessed the direct economic effects of the 2005-06 HPAI outbreaks on contracted turkey producers in Turkey in 2007. The data were obtained from 71 randomly selected, contracted turkey farms (producing 23% of the national turkey meat in Turkey in 2005) from five provinces for four integrated firms, which account for 67% of the national turkey production. Each farm was visited once for an oral interview conducted by the authors in 2007, using a questionnaire survey. The financial data before and after highly pathogenic avian influenza (HPAI) H5N1 outbreak periods were obtained from available financial records. Changes in production and economics parameters before and after the HPAI H5N1 outbreak periods were compared. In the analyses, the "before the HPAI H5N1 outbreak" period was stated as October 1, 2004, to May 31, 2005, whereas the "after the HPAI H5N1 outbreak" period was stated as the 8-mo between October 1, 2005, and May 31, 2006. The research revealed that changes in the technical parameters (number of hired labor, feed conversion rate, mortality rate, and the length of fattening period) were not found to be statistically significant at P > 0.05. However, there were severe effects of the HPAI H5N1 outbreaks on the economic parameters of the turkey production. The contracted turkey producers lost on average 0.9 cycles (38%) of production, and their management fees were reduced by 9.3% in the 8 mo after the outbreaks. As a result, the production level and enterprise income declined by 36% and 39%, respectively. About 93% of the producers did not do any other supplementary work during the idle production period; 59% of the producers had to use on average 4970TL (US$3200) from their personnel saving during the HPAI H5N1 outbreaks. About 62% of the producers stated that they had been considering expanding their businesses, but suspended the idea because of the outbreak, and 80% of the producers increased the biosecurity measures after the outbreaks. The futures of the contracted turkey producers are fully dependent on those of the integrated firms. Any negative effects on the latter appear to be directly transferred to the former. However, the government neglected contracted producers in the HPAI compensation programs. PMID:20521667

Yalcin, Cengiz; Sipahi, Cevat; Aral, Yilmaz; Cevger, Yavuz

2010-03-01

321

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

322

Process for producing gasoline of high octane number and particularly lead free gasoline, from olefininc c3-c4 cuts  

SciTech Connect

Lead free gasoline of high octane number is obtained from C/sub 3/ and C/sub 4/ olefinic cuts as follows: propylene contained in the C/sub 3/ cut is oligomerized, at least 80% of the isobutene and less than 40% of the n-butenes of the C/sub 4/ cut are oligomerized to form an oligomerizate distilling in the gasoline range, which is separated from the unreacted C/sub 4/ hydrocarbons, the latter are subsequently alkylated to form a gasoline fraction which can be admixed with the oligomerizates of the Cnumber and the C/sub 4/ cuts to produce the desired high octane gasoline.

Hellin, M.; Juguin, B.; Torck, B.; Vu, Q. D.

1981-05-19

323

Exome capture from saliva produces high quality genomic and metagenomic data  

PubMed Central

Background Targeted capture of genomic regions reduces sequencing cost while generating higher coverage by allowing biomedical researchers to focus on specific loci of interest, such as exons. Targeted capture also has the potential to facilitate the generation of genomic data from DNA collected via saliva or buccal cells. DNA samples derived from these cell types tend to have a lower human DNA yield, may be degraded from age and/or have contamination from bacteria or other ambient oral microbiota. However, thousands of samples have been previously collected from these cell types, and saliva collection has the advantage that it is a non-invasive and appropriate for a wide variety of research. Results We demonstrate successful enrichment and sequencing of 15 South African KhoeSan exomes and 2 full genomes with samples initially derived from saliva. The expanded exome dataset enables us to characterize genetic diversity free from ascertainment bias for multiple KhoeSan populations, including new exome data from six HGDP Namibian San, revealing substantial population structure across the Kalahari Desert region. Additionally, we discover and independently verify thirty-one previously unknown KIR alleles using methods we developed to accurately map and call the highly polymorphic HLA and KIR loci from exome capture data. Finally, we show that exome capture of saliva-derived DNA yields sufficient non-human sequences to characterize oral microbial communities, including detection of bacteria linked to oral disease (e.g. Prevotella melaninogenica). For comparison, two samples were sequenced using standard full genome library preparation without exome capture and we found no systematic bias of metagenomic information between exome-captured and non-captured data. Conclusions DNA from human saliva samples, collected and extracted using standard procedures, can be used to successfully sequence high quality human exomes, and metagenomic data can be derived from non-human reads. We find that individuals from the Kalahari carry a higher oral pathogenic microbial load than samples surveyed in the Human Microbiome Project. Additionally, rare variants present in the exomes suggest strong population structure across different KhoeSan populations. PMID:24708091

2014-01-01

324

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

325

Application of High-Density DNA Resequencing Microarray for Detection and Characterization of Botulinum Neurotoxin-Producing Clostridia  

PubMed Central

Background Clostridium botulinum and related clostridia express extremely potent toxins known as botulinum neurotoxins (BoNTs) that cause severe, potentially lethal intoxications in humans. These BoNT-producing bacteria are categorized in seven major toxinotypes (A through G) and several subtypes. The high diversity in nucleotide sequence and genetic organization of the gene cluster encoding the BoNT components poses a great challenge for the screening and characterization of BoNT-producing strains. Methodology/Principal Findings In the present study, we designed and evaluated the performances of a resequencing microarray (RMA), the PathogenId v2.0, combined with an automated data approach for the simultaneous detection and characterization of BoNT-producing clostridia. The unique design of the PathogenID v2.0 array allows the simultaneous detection and characterization of 48 sequences targeting the BoNT gene cluster components. This approach allowed successful identification and typing of representative strains of the different toxinotypes and subtypes, as well as the neurotoxin-producing C. botulinum strain in a naturally contaminated food sample. Moreover, the method allowed fine characterization of the different neurotoxin gene cluster components of all studied strains, including genomic regions exhibiting up to 24.65% divergence with the sequences tiled on the arrays. Conclusions/Significance The severity of the disease demands rapid and accurate means for performing risk assessments of BoNT-producing clostridia and for tracing potentials sources of contamination in outbreak situations. The RMA approach constitutes an essential higher echelon component in a diagnostics and surveillance pipeline. In addition, it is an important asset to characterise potential outbreak related strains, but also environment isolates, in order to obtain a better picture of the molecular epidemiology of BoNT-producing clostridia. PMID:23818983

Vanhomwegen, Jessica; Berthet, Nicolas; Mazuet, Christelle; Guigon, Ghislaine; Vallaeys, Tatiana; Stamboliyska, Rayna; Dubois, Philippe; Kennedy, Giulia C.; Cole, Stewart T.; Caro, Valerie; Manuguerra, Jean-Claude; Popoff, Michel-Robert

2013-01-01

326

Widespread occurrence of neonicotinoid insecticides in streams in a high corn and soybean producing region, USA.  

PubMed

Neonicotinoid insecticides are of environmental concern, but little is known about their occurrence in surface water. An area of intense corn and soybean production in the Midwestern United States was chosen to study this issue because of the high agricultural use of neonicotinoids via both seed treatments and other forms of application. Water samples were collected from nine stream sites during the 2013 growing season. The results for the 79 water samples documented similar patterns among sites for both frequency of detection and concentration (maximum:median) with clothianidin (75%, 257 ng/L:8.2 ng/L) > thiamethoxam (47%, 185 ng/L:<2 ng/L) > imidacloprid (23%, 42.7 ng/L: <2 ng/L). Neonicotinoids were detected at all nine sites sampled even though the basin areas spanned four orders of magnitude. Temporal patterns in concentrations reveal pulses of neonicotinoids associated with rainfall events during crop planting, suggesting seed treatments as their likely source. PMID:25042208

Hladik, Michelle L; Kolpin, Dana W; Kuivila, Kathryn M

2014-10-01

327

WETTABILITY ALTERATION OF CARBONATE ROCK MEDIATED BY BIOSURFACTANT PRODUCED FROM HIGH-STARCH AGRICULTURAL EFFLUENTS  

SciTech Connect

Surfactants can be used to alter wettability of reservoir rock, increasing spontaneous imbibition and thus improving oil yields. Commercial synthetic surfactants are often prohibitively expensive and so a crude preparation of the anionic biosurfactant, surfactin, from Bacillus subtilis grown on high-starch industrial and agricultural effluents has been proposed as an economical alternative. To assess the effectiveness of the surfactin, it is compared to commercially available surfactants. In selecting a suitable benchmark surfactant, two metrics are examined: the ability of the surfactants to alter wettability at low concentrations, and the degree to which they are absorbed onto reservoir matrix. We review the literature to survey the adsorption models that have been developed to describe surfactant adsorption in porous media. These models are evaluated using the experimental data from this study. Crushed carbonate rock samples are cleaned and aged in crude oil. The wettability change mediated by dilute solutions of commercial anionic surfactants and surfactin is assessed using a two-phase separation; and surfactant loss due to retention and adsorption the rock is determined.

Mehdi Salehi; Stephen Johnson; Gregory Bala; Jenn-Tai Liang

2006-09-01

328

Review of high-throughput techniques for detecting solid phase Transformation from material libraries produced by combinatorial methods  

NASA Technical Reports Server (NTRS)

High-throughput measurement techniques are reviewed for solid phase transformation from materials produced by combinatorial methods, which are highly efficient concepts to fabricate large variety of material libraries with different compositional gradients on a single wafer. Combinatorial methods hold high potential for reducing the time and costs associated with the development of new materials, as compared to time-consuming and labor-intensive conventional methods that test large batches of material, one- composition at a time. These high-throughput techniques can be automated to rapidly capture and analyze data, using the entire material library on a single wafer, thereby accelerating the pace of materials discovery and knowledge generation for solid phase transformations. The review covers experimental techniques that are applicable to inorganic materials such as shape memory alloys, graded materials, metal hydrides, ferric materials, semiconductors and industrial alloys.

Lee, Jonathan A.

2005-01-01

329

Clospore: a liquid medium for producing high titers of semi-purified spores of Clostridium difficile.  

PubMed

Clostridium difficile continues to cause infections in healthcare and other settings. Its spores survive well indoors and require sporicidal chemicals for infection control. However, proper testing of disinfectants is impeded due to difficulties in obtaining viable spores of high enough quality and titers to meet current regulations for sporicidal claims. A new liquid medium (Clospore) has been developed, based on a systematic review of the compositions of 20 other available media. C. difficile spores grown in the new medium and treated with a mixture of lysozyme and trypsin yielded final suspensions with > 10(9) CFU/mL of viable spores, with a purity of > 91% as tested by spore-staining and phase-contrast microscopy. The spores showed a biological decay rate of about 0.1 log10/month when dried on metal disks and stored indoors (air temperature 23 +/- 2 degrees C; relative humidity 52.76 +/- 15.08%). Heating the purified spore suspensions to 70 degrees C for 10 min to inactivate any vegetative cells showed no spore activation or inactivation. The spores could be stored for at least 14 months either refrigerated (4 degrees C) or frozen (-20 or -80 degrees C) in 50% (v/v) ethanol with virtually no loss in viability. The resistance of the enzyme-treated spores to three levels of sodium hypochlorite (1000, 3000, and 5000 ppm), using a standardized quantitative carrier test, was almost identical to that of the spores concentrated by centrifugation alone. The described procedure has been successfully applied to four standard (ATCC) and six clinical strains of C. difficile. PMID:21563698

Perez, Justo; Springthorpe, V Susan; Sattar, Syed A

2011-01-01

330

High prevalence of Cfr-producing Staphylococcus species in retail meat in Guangzhou, China  

PubMed Central

Background The emergence and wide distribution of the transferable gene for linezolid resistance, cfr, in staphylococci of human and animal origins is of great concern as it poses a serious threat to the public health. In the present study, we investigated the emergence and presence of the multiresistance gene, cfr, in retail meat sourced from supermarkets and free markets of Guangzhou, China. Results A total of 118 pork and chicken samples, collected from Guangzhou markets, were screened by PCR for cfr. Twenty-two Staphylococcus isolates obtained from 12 pork and 10 chicken samples harbored cfr. The 22 cfr-positive staphylococci isolates, including Staphylococcus equorum (n?=?8), Staphylococcus simulans (n?=?7), Staphylococcus cohnii (n?=?4), and Staphylococcus sciuri (n?=?3), exhibited 17 major SmaI pulsed-field gel electrophoresis (PFGE) patterns. In 14 isolates, cfr was located on the plasmids. Sequence analysis revealed that the genetic structures (including ?tnpA of Tn558, IS21-558, ?tnpB, and tnpC of Tn558, orf138, fexA) of cfr in plasmid pHNTLD18 of a S. sciuri strain and in the plasmid pHNLKJC2 (including rep, ?pre/mob, cfr, pre/mob and partial ermC) of a S. equorum strain were identical or similar to the corresponding regions of some plasmids in staphylococcal species of animal and human origins. Conclusions To the best of our knowledge, this is the first study to report the presence of the multiresistance gene, cfr, in animal meat. A high occurrence of cfr was observed in the tested retail meat samples. Thus, it is important to monitor the presence of cfr in animal foods in China. PMID:24913069

2014-01-01

331

Mycobacterium leprae Hsp65 administration reduces the lifespan of aged high antibody producer mice  

PubMed Central

Background Aging process may result in immune modifications that lead to disruption of innate and acquired immunity mechanisms that may induce chronic-degenerative events. The heat shock proteins (Hsp), phylogeneticaly conserved among organisms, present as main function the ability of folding and refolding proteins, but they also are associated with chronic-degenerative disorders. Here were evaluated the role of M. leprae native Hsp65 (WT) and its point-mutated (K409A) on survival and anti-DNA and anti-Hsp65 antibody production of aged genetically selected mice for high (HIII) and low (LIII) antibody production; data from 120- and 270-days old mice (named “adult” or “aged”, respectively) were compared. Results WT Hsp65 administration induces reduction in the mean survival time of adult and aged female HIII mice, this effect being stronger in aged individuals. Surprisingly, the native protein administration increased the survival of aged female LIII when compared to K409A and control groups. No survival differences were observed in aged male mice after Hsp65 proteins inoculation. We observed increase in IgG1 anti-Hsp65 in WT and K409A aged HIII female mice groups and no marked changes in the anti-DNA (adult and aged HIII) and anti-Hsp65 IgG1 or IgG2a isotypes production in adult HIII female and aged male mice. LIII male mice presented increased anti-DNA and anti-Hsp65 IgG2a isotype production after WT or K409A injection, and LIII female groups showed no alterations. Conclusions The results revealed that the WT Hsp65 interferes with survival of aged HIII female mice without involvement of a remarkable IgG1 and IgG2a anti-DNA and anti-Hsp65 antibodies production. The deleterious effects of Hsp65 on survival time in aged HIII female mice could be linked to a gender-effect and are in agreement with those previously reported in lupus-prone mice. PMID:24669842

2014-01-01

332

Formation of Highly Twisted Ribbons in a Carboxymethylcellulase Gene-Disrupted Strain of a Cellulose-Producing Bacterium  

PubMed Central

Cellulases are enzymes that normally digest cellulose; however, some are known to play essential roles in cellulose biosynthesis. Although some endogenous cellulases of plants and cellulose-producing bacteria are reportedly involved in cellulose production, their functions in cellulose production are unknown. In this study, we demonstrated that disruption of the cellulase (carboxymethylcellulase) gene causes irregular packing of de novo-synthesized fibrils in Gluconacetobacter xylinus, a cellulose-producing bacterium. Cellulose production was remarkably reduced and small amounts of particulate material were accumulated in the culture of a cmcax-disrupted G. xylinus strain (F2-2). The particulate material was shown to contain cellulose by both solid-state 13C nuclear magnetic resonance analysis and Fourier transform infrared spectroscopy analysis. Electron microscopy revealed that the cellulose fibrils produced by the F2-2 cells were highly twisted compared with those produced by control cells. This hypertwisting of the fibrils may reduce cellulose synthesis in the F2-2 strains. PMID:23243308

Sugano, Yasushi; Shoda, Makoto; Sakakibara, Hitoshi; Oiwa, Kazuhiro; Tuzi, Satoru; Imai, Tomoya; Sugiyama, Junji; Takeuchi, Miyuki; Yamauchi, Daisuke

2013-01-01

333

A bisexually reproducing all-triploid vertebrate.  

PubMed

Green toads are common in the Palaearctic region, where they have differentiated into several taxa. The toads exist with variable amounts of ploidy, similar to other anuran species or reptiles. In vertebrate biology, the very rare occurrence of triploidy is coupled with infertility or unisexuality, or requires the coexistence of individuals of different ploidy in a reproductive community. The reproduction of naturally occurring triploids has been reported to occur only through parthenogenesis, gynogenesis or hybridogenesis. The bisexual reproduction of pure triploids has been considered to be impossible because of the problem of equally distributing three chromosome sets in meiosis. Here we report geographically isolated populations of green toads (Bufo viridis complex) that are all-triploid and reproduce bisexually. PMID:11836500

Stöck, Matthias; Lamatsch, Dunja K; Steinlein, Claus; Epplen, Jörg T; Grosse, Wolf-Rüdiger; Hock, Robert; Klapperstück, Thomas; Lampert, Kathrin P; Scheer, Ulrich; Schmid, Michael; Schartl, Manfred

2002-03-01

334

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. PMID:22690019

Boos, Dennis D.; Stefanski, Leonard A.

2011-01-01

335

Repeatability and reproducibility of earprint acquisition.  

PubMed

For all forensic disciplines dealing with identification -- e.g., of glass, tool marks, fibers, faces, fingers, handwriting, speakers -- in which manual (subjective, nonautomated) processes play a role, operator dependencies are relevant. With respect to earprint identification, in the period 2002-2005, the Forensic Ear Identification research project collected a database of 1229 donors, three prints per ear, and laid down a "best practice" for print acquisition. Repeatability and reproducibility aspects of the print acquisition are tested. The study suggests that different operators may acquire prints of differing quality, with equal error rates of the matching system ranging from 9% to 19%. Moreover, it turns out that "matching" earprints are more alike when taken in a consecutive row than when taken on separate occasions. This underlines the importance of (1) studying operator effects, (2) operator training, and (3) not gathering "matching" reference material at the same occasion. PMID:18366563

Alberink, Ivo; Ruifrok, Arnout

2008-03-01

336

Is Grannum grading of the placenta reproducible?  

NASA Astrophysics Data System (ADS)

Current ultrasound assessment of placental calcification relies on Grannum grading. The aim of this study was to assess if this method is reproducible by measuring inter- and intra-observer variation in grading placental images, under strictly controlled viewing conditions. Thirty placental images were acquired and digitally saved. Five experienced sonographers independently graded the images on two separate occasions. In order to eliminate any technological factors which could affect data reliability and consistency all observers reviewed images at the same time. To optimise viewing conditions ambient lighting was maintained between 25-40 lux, with monitors calibrated to the GSDF standard to ensure consistent brightness and contrast. Kappa (?) analysis of the grades assigned was used to measure inter- and intra-observer reliability. Intra-observer agreement had a moderate mean ?-value of 0.55, with individual comparisons ranging from 0.30 to 0.86. Two images saved from the same patient, during the same scan, were each graded as I, II and III by the same observer. A mean ?-value of 0.30 (range from 0.13 to 0.55) indicated fair inter-observer agreement over the two occasions and only one image was graded consistently the same by all five observers. The study findings confirmed the lack of reproducibility associated with Grannum grading of the placenta despite optimal viewing conditions and highlight the need for new methods of assessing placental health in order to improve neonatal outcomes. Alternative methods for quantifying placental calcification such as a software based technique and 3D ultrasound assessment need to be explored.

Moran, Mary; Ryan, John; Brennan, Patrick C.; Higgins, Mary; McAuliffe, Fionnuala M.

2009-02-01

337

Reproducible research: a bioinformatics case study.  

PubMed

While scientific research and the methodologies involved have gone through substantial technological evolution the technology involved in the publication of the results of these endeavors has remained relatively stagnant. Publication is largely done in the same manner today as it was fifty years ago. Many journals have adopted electronic formats, however, their orientation and style is little different from a printed document. The documents tend to be static and take little advantage of computational resources that might be available. Recent work, Gentleman and Temple Lang (2003), suggests a methodology and basic infrastructure that can be used to publish documents in a substantially different way. Their approach is suitable for the publication of papers whose message relies on computation. Stated quite simply, Gentleman and Temple Lang (2003) propose a paradigm where documents are mixtures of code and text. Such documents may be self-contained or they may be a component of a compendium which provides the infrastructure needed to provide access to data and supporting software. These documents, or compendiums, can be processed in a number of different ways. One transformation will be to replace the code with its output -- thereby providing the familiar, but limited, static document.

In this paper we apply these concepts to a seminal paper in bioinformatics, namely The Molecular Classification of Cancer, Golub et al (1999). The authors of that paper have generously provided data and other information that have allowed us to largely reproduce their results. Rather than reproduce this paper exactly we demonstrate that such a reproduction is possible and instead concentrate on demonstrating the usefulness of the compendium concept itself. PMID:16646837

Gentleman, Robert

2005-01-01

338

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. PMID:18687108

Stengarde, Lena; Traven, Madeleine; Emanuelson, Ulf; Holtenius, Kjell; Hultgren, Jan; Niskanen, Rauni

2008-01-01

339

Thromboplastin Bilbao: reproducibility and sensitivity of a Spanish thromboplastin.  

PubMed

Prothrombin time (PT) is the control test for oral anticoagulant therapy as well as the screening test for defects of the extrinsic pathway of coagulation. Its responsiveness to decreased extrinsic clotting factors depends on the source and type of tissue factor thromboplastin extract. In 1994, a rabbit brain thromboplastin - Thromboplastin Bilbao (TBi) - was introduced as a replacement for a human brain preparation used since 1983, with the aim of establishing a national standard. The purpose of this study was to check the reproducibility, the inter-assay/intra-assay accuracy and the stability of this reagent under temperature changes and over time. A method modified from Frei et al. [World Health Organisation Regional Publications, Eastern Mediterranean Series, Alexandria, 1995] was used for the preparation of thromboplastin extract. Thirty-five batches of human TBi were prepared from 1983 to 1988, while from 1993 to 1999 13 batches of rabbit TBi were produced. The inter-assay reproducibility of rabbit TBi exhibited a coefficient of variation (CV) of 1.07-1.57% for normal plasma and of 1.25-2.56% for anticoagulated plasma. The intra-assay CV was 0.06-1.30% for normal plasma and 1.23-2.66% for anticoagulated plasma. The stability of the reagent to temperature changes and time was also estimated, with similar results for the two thromboplastins. As a result of the Oral Anticoagulant Treatment Quality Assessment Scheme in the Basque Country, an in-house rabbit thromboplastin with good sensitivity and reproducibility was developed. PMID:12372924

Vacas, M; Aguirrebeitia, M J; Lafuente, P J; Unanue, I; Iriarte, J A

2002-01-01

340

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

2013-08-01

341

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

342

Aspergillus 6V4, a Strain Isolated from Manipueira, Produces High Amylases Levels by Using Wheat Bran as a Substrate.  

PubMed

The aim of this study was screening fungi strains, isolated from manipueira (a liquid subproduct obtained from the flour production of Manihot esculenta), for amylases production and investigating production of these enzymes by the strain Aspergillus 6V4. The fungi isolated from manipueira belonged to Ascomycota phylum. The strain Aspergillus 6V4 was the best amylase producer in the screening assay of starch hydrolysis in petri dishes (ASHPD) and in the assay in submerged fermentation (ASbF). The strain Aspergillus 6V4 produced high amylase levels (335?UI/L) using wheat bran infusion as the exclusive substrate and the supplementation of this substrate with peptone decreased the production of this enzyme. The moisture content of 70% was the best condition for the production of Aspergillus 6V4 amylases (385?IU/g) in solid state fermentation (SSF). PMID:24724017

Celestino, Jessyca Dos Reis; Duarte, Ana Caroline; Silva, Cláudia Maria de Melo; Sena, Hellen Holanda; Ferreira, Maria do Perpétuo Socorro Borges Carriço; Mallmann, Neila Hiraishi; Lima, Natacha Pinheiro Costa; Tavares, Chanderlei de Castro; de Souza, Rodrigo Otávio Silva; Souza, Erica Simplício; Souza, João Vicente Braga

2014-01-01

343

Structural and compositional variations in Ta 3N 5 produced by high-temperature ammonolysis of tantalum oxide  

NASA Astrophysics Data System (ADS)

A series of samples of Ta 3N 5 ( Cmcm, a=3.89 Å, b=10.22 Å, c=10.28 Å) have been produced by high-temperature ammonolysis of amorphous tantalum oxide under various temperature and heating time regimes. These were characterised by powder diffraction (X-ray and neutron), combustion microanalysis, thermogravimetric analysis and transmission electron microscopy. All samples were found to contain oxide in the 3-coordinate anion site and the b-axis length was sensitive to compositional variation. Samples heated for longer times at higher temperatures were anion deficient. The compositions of the samples have been related to their optical band gap UV-visible spectra. This work highlights the importance of careful compositional analysis when samples of nitride materials are produced for real-world applications.

Henderson, Stuart J.; Hector, Andrew L.

2006-11-01

344

Experimental Investigation of a Pseudospark-Produced High-Brightness Electron Beam for X-ray Applications  

NASA Astrophysics Data System (ADS)

This paper presents the progress in the experimental investigation of pseudospark-produced electron beams to drive x-ray emission for medical devices. Experiments are performed to determine the discharge behaviors (breakdown characteristics, electron beam generation efficiency) and the qualities of electron beams (peak current, energy spread, and transverse emittance) produced by a thirty-gap pseudospark device. The system is operated at 70kV. The breakdown voltage and discharge current are measured by a high voltage probe and Rogowski coil. A movable multi-probe array consists of 4 electrostatic probes to measure the beam currents profile at different radial and axial locations. Thus the energy spread and rms emittance of electron beams can be determined radially and axially. A discussion of the measured discharge characteristics and beam parameters to drive x-ray emission are also presented.

Hu, Jing; Rovey, Joshua

2010-11-01

345

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. 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

2012-01-01

346

REPRODUCIBILITY OF FMRI ACTIVATIONS ASSOCIATED WITH AUDITORY SENTENCE COMPREHENSION  

PubMed Central

Reproducibility of three different aspects of fMRI activations—namely binary activation maps, effect size and spatial distribution of local maxima—was evaluated for an auditory sentence comprehension task with high attention demand on a group of 17 subjects that were scanned on five different occasions. While in the scanner subjects were asked to listen to series of six short everyday sentences from the CUNY sentence test. Comprehension and attention to the stimuli was monitored after each listen condition epoch by having subjects answer a series of multiple choice questions. Statistical maps of activation for the listen condition were computed at three different levels: overall results for all imaging sessions, group-level/single-session results for each of the five imaging occasions, and single-subject/single-session results computed for each subject and each scanning occasion independently. The experimental task recruited a distributed bilateral network with processing nodes located in lateral temporal cortex, inferior frontal cortex, medial BA6, medial occipital cortex and subcortical structures such as the putamen and the thalamus. Reproducibility of these activations at the group level was high (83.95% of the imaged volume was consistently classified as active/inactive across all five imaging sessions), indicating that sites of neuronal activity associated with auditory comprehension can reliably be detected with fMRI in healthy subjects, across repeated measures after group averaging. At the single-subject level reproducibility ranged from moderate to high, although no significant differences were found on behavioral measures across subjects or sessions. This result suggests that contextual differences—i.e., those specific to each imaging session, can modulate our ability to detect fMRI activations associated with speech comprehension in individual subjects. PMID:20933093

Gonzalez-Castillo, Javier; Talavage, Thomas M.

2010-01-01

347

High-throughput method development for sensitive, accurate, and reproducible quantification of therapeutic monoclonal antibodies in tissues using orthogonal array optimization and nano liquid chromatography/selected reaction monitoring mass spectrometry.  

PubMed

Although liquid chromatography/mass spectrometry using selected reaction monitoring (LC/SRM-MS) holds great promise for targeted protein analysis, quantification of therapeutic monoclonal antibody (mAb) in tissues represents a daunting challenge due to the extremely low tissue levels, complexity of tissue matrixes, and the absence of an efficient strategy to develop an optimal LC/SRM-MS method. Here we describe a high-throughput, streamlined strategy for the development of sensitive, selective, and reliable quantitative methods of mAb in tissue matrixes. A sensitive nano-LC/nanospray-MS method was employed to achieve a low lower limit of quantification (LOQ). For selection of signature peptides (SP), the SP candidates were identified by a high-resolution Orbitrap and then optimal SRM conditions for each candidate were obtained using a high-throughput, on-the-fly orthogonal array optimization (OAO) strategy, which is capable of optimizing a large set of SP candidates within a single nano-LC/SRM-MS run. Using the optimized conditions, the candidates were experimentally evaluated for both sensitivity and stability in the target matrixes, and SP selection was based on the results of the evaluation. Two unique SP, respectively from the light and heavy chain, were chosen for quantification of each mAb. The use of two SP improves the quantitative reliability by gauging possible degradation/modification of the mAb. Standard mAb proteins with verified purities were utilized for calibration curves, to prevent the quantitative biases that may otherwise occur when synthesized peptides were used as calibrators. We showed a proof of concept by rapidly developing sensitive nano-LC/SRM-MS methods for quantifying two mAb (8c2 and cT84.66) in multiple preclinical tissues. High sensitivity was achieved for both mAb with LOQ ranged from 0.156 to 0.312 ?g/g across different tissues, and the overall procedure showed a wide dynamic range (?500-fold) and good accuracy [relative error (RE) < 18.8%] and precision [interbatch relative standard deviation (RSD) < 18.1%, intrabatch RSD < 17.2%]. The quantitative method was applied to a comprehensive investigation of the steady-state tissue distribution of 8c2 in wild-type mice versus those deficient in FcRn ?-chain, Fc?IIb, and Fc?RI/Fc?RIII, following a chronic dosing regimen. This work represents the first extensive quantification of mAb in tissues by an LC/MS-based method. PMID:22519810

Duan, Xiaotao; Abuqayyas, Lubna; Dai, Lipeng; Balthasar, Joseph P; Qu, Jun

2012-05-15

348

A Reproducible Oral Microcosm Biofilm Model for Testing Dental Materials  

PubMed Central

Aims Most studies of biofilm effects on dental materials use single-species biofilms, or consortia. Microcosm biofilms grown directly from saliva or plaque are much more diverse, but difficult to characterize. We used the Human Oral Microbial Identification Microarray (HOMIM) to validate a reproducible oral microcosm model. Methods and Results Saliva and dental plaque were collected from adults and children. Hydroxyapatite and dental composite disks were inoculated with either saliva or plaque, and microcosm biofilms were grown in a CDC biofilm reactor. In later experiments, the reactor was pulsed with sucrose. DNA from inoculums and microcosms were analyzed by HOMIM for 272 species. Microcosms included about 60% of species from the original inoculum. Biofilms grown on hydroxyapatite and composites were extremely similar. Sucrose-pulsing decreased diversity and pH, but increased the abundance of Streptococcus and Veilonella. Biofilms from the same donor, grown at different times, clustered together. Conclusions This model produced reproducible microcosm biofilms that were representative of the oral microbiota. Sucrose induced changes associated with dental caries. Significance and Impact of the Study This is the first use of HOMIM to validate an oral microcosm model that can be used to study the effects of complex biofilms on dental materials. PMID:22925110

Rudney, J.D.; Chen, R.; Lenton, P.; Li, J.; Li, Y.; Jones, R.S.; Reilly, C.; Fok, A.S.; Aparicio, C.

2012-01-01

349

Dose equivalent near the bone-soft tissue interface from nuclear fragments produced by high-energy protons  

NASA Technical Reports Server (NTRS)

During manned space missions, high-energy nucleons of cosmic and solar origin collide with atomic nuclei of the human body and produce a broad linear energy transfer spectrum of secondary particles, called target fragments. These nuclear fragments are often more biologically harmful than the direct ionization of the incident nucleon. That these secondary particles increase tissue absorbed dose in regions adjacent to the bone-soft tissue interface was demonstrated in a previous publication. To assess radiological risks to tissue near the bone-soft tissue interface, a computer transport model for nuclear fragments produced by high energy nucleons was used in this study to calculate integral linear energy transfer spectra and dose equivalents resulting from nuclear collisions of 1-GeV protons transversing bone and red bone marrow. In terms of dose equivalent averaged over trabecular bone marrow, target fragments emitted from interactions in both tissues are predicted to be at least as important as the direct ionization of the primary protons-twice as important, if recently recommended radiation weighting factors and "worst-case" geometry are used. The use of conventional dosimetry (absorbed dose weighted by aa linear energy transfer-dependent quality factor) as an appropriate framework for predicting risk from low fluences of high-linear energy transfer target fragments is discussed.

Shavers, M. R.; Poston, J. W.; Cucinotta, F. A.; Wilson, J. W.

1996-01-01

350

High damping Al-Fe-Mo-Si/Zn-Al composites produced by rapidly solidified powder metallurgy process  

SciTech Connect

The metallic materials commonly used in aircraft and aerospace fields, such as aluminum and titanium alloys, steels, etc., show extremely low damping capacity (usually of the order of or less than 10{sup {minus}3}). Thus, some problems related to vibration may emerge and influence the reliability, safety and life of airplanes, satellites, etc. It has been reported that almost two thirds of errors for rockets and satellites are related to vibration and noise. One effective way to solve these vibration-related problems is to adopt high damping metallic materials. Conventional high damping alloys exhibit damping capacity above 10{sup {minus}2}, however, their densities are usually great than 5 x 10{sup 3} kg m{sup {minus}3}, or their strengths are less than 200 MPa (for alloys based on dislocation damping), making them impossible to be applied to aircraft and aerospace areas. Recently, some low-density high-damping metal/metal composites based on aluminum and high damping alloys have been developed in Beijing Institute of Aeronautical Materials (BIAM) by the rapidly solidified power metallurgy process. This paper aims to report the properties of the composites based on a high temperature Al-Fe-Mo-Si alloy and a high damping Zn-Al alloy, and compare them with that of 2618-T61 alloy produced by the ingot metallurgy process.

Li, P.Y.; Dai, S.L.; Chai, S.C.; Li, Y.R.

2000-05-10

351

Reproducing or Challenging Power in the Questions We Ask and the Methods We Use: A Framework for Activist Research in Urban Education  

Microsoft Academic Search

Many have argued that educational research does little to change (and may actually reproduce) the social-structural inequalities shaping the quality of high-poverty urban schools. Building from this premise, this paper asks: How can university-based scholars of urban education do research that encourages, produces, or informs change in urban schools and the conditions that shape them? I examine two broad aspects

Kysa Nygreen

2006-01-01

352

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

353

[Isolation and identification of lipopeptides produced by Bacillus subtilis using high performance liquid chromatography and electrospray ionization mass spectrometry].  

PubMed

Bacillus subtilis JA produces a broad spectrum of bioactive lipopeptides with great potential applications in agriculture and industry. Crude lipopeptides were extracted with 100% methanol from the precipitate which was obtained by adding 6 mol/L HCl to the cell-free culture broth. The crude extract was separated on a Diamonsil C18 column (5 microm, 250 mm x 4.6 mm) in reversed-phase high performance liquid chromatography (HPLC) system to separate the lipopeptide homologues. Five peaks were eluted from HPLC. Electrospray ionization mass spectrometry (ESI-MS) was used to analyze each HPLC fraction. The results showed three series of ion peaks. According to the values of m/z, the three series of ions were classified into surfactin, iturin and fengycin homologues, which were well-known biosurfactants produced by B. subtilis strains. The major ions were structurally characterized using tandem mass spectrometry. This study suggested a reasonable method for the isolation and identification of lipopeptides produced by B. subtilis strains. PMID:18724673

Chen, Hua; Wang, Li; Yuan, Chengling; Zheng, Zhiming; Yu, Zengliang

2008-05-01

354

Reproducibility of binary-mixture toxicity studies.  

PubMed

Binary-mixture studies often are conducted with the aim of elucidating the effect of one specific chemical on the biological action of another. The results can be interpreted in relation to reference models by the use of response-surface analyses and isobolograms. The amount of data needed for these analyses is, however, extensive, and the experiments therefore rarely are repeated. In the present study, we investigate the reproducibility of isobole shapes of binary-mixture toxicity experiments in terms of deviation from the reference model of concentration addition (CA), dose-level dependence, and isobole asymmetry. We use data from four herbicide mixtures tested in three to five independent experiments on the aquatic test plant Lemna minor and the terrestrial plant Tripleurospermum inodorum. The results showed that the variation both within and among experiments was approximately half the size for the aquatic test system compared to the terrestrial system. As a consequence, a consistent deviation from CA could be obtained in three of four herbicide mixtures for L. minor, whereas this was only the case for one or two of the herbicide mixtures tested on T. inodorum. For one mixture on T. inodorum, both CA synergism and antagonism were detected. Dose-dependent effects could not be repeated consistently, just as the asymmetry found in some isoboles could not. The study emphasizes the importance of repeating mixture toxicity experiments, especially for test systems with large variability, and using caution when drawing biological conclusions from the test results. PMID:17269472

Cedergreen, Nina; Kudsk, Per; Mathiassen, Solvejg Kopp; Sørensen, Helle; Streibig, Jens Carl

2007-01-01

355

Microstructural characterization of low and high carbon CoCrMo alloy nanoparticles produced by mechanical milling  

NASA Astrophysics Data System (ADS)

CoCrMo alloys are utilised as the main material in hip prostheses. The link between this type of hip prosthesis and chronic pain remains unclear. Studies suggest that wear debris generated in-vivo may be related to post-operative complications such as inflammation. These alloys can contain different amounts of carbon, which improves the mechanical properties of the alloy. However, the formation of carbides could become sites that initiate corrosion, releasing ions and/or particles into the human body. This study analysed the mechanical milling of alloys containing both high and low carbon levels in relevant biological media, as an alternative route to generate wear debris. The results show that low carbon alloys produce significantly more nanoparticles than high carbon alloys. During the milling process, strain induces an fcc to hcp phase transformation. Evidence for cobalt and molybdenum dissolution in the presence of serum was confirmed by ICP-MS and TEM EDX techniques.

Simoes, T. A.; Goode, A. E.; Porter, A. E.; Ryan, M. P.; Milne, S. J.; Brown, A. P.; Brydson, R. M. D.

2014-06-01

356

Prevalence of extended-spectrum ?-lactamase-producing Enterobacteriaceae in humans living in municipalities with high and low broiler density.  

PubMed

Prevalence of, and risk factors for, carriage of extended-spectrum ?-lactamase (ESBL) -producing Enterobacteriaceae were determined for 1025 Dutch adults in municipalities with either high or low broiler densities. Overall prevalence of ESBL carriage was 5.1%. The hypothesis that individuals in areas with high broiler densities are at greater risk for ESBL carriage was rejected, as the risk was lower (OR = 0.45; p 0.009) for these individuals. Owning a horse increased the risk (OR = 4.69; p ?0.0001), but horse owners often owned multiple species of companion animals. Routes of transmission from animals to humans in the community, and the role of poultry in this process, remain to be elucidated. PMID:23397953

Huijbers, P M C; de Kraker, M; Graat, E A M; van Hoek, A H A M; van Santen, M G; de Jong, M C M; van Duijkeren, E; de Greeff, S C

2013-06-01

357

High-Temperature Oxidation Behavior of Two Nickel-Based Superalloys Produced by Metal Injection Molding for Aero Engine Applications  

NASA Astrophysics Data System (ADS)

For different high-temperature applications like aero engines or turbochargers, metal injection molding (MIM) of superalloys is an interesting processing alternative. For operation at high temperatures, oxidation behavior of superalloys produced by MIM needs to match the standard of cast or forged material. The oxidation behavior of nickel-based superalloys Inconel 713 and MAR-M247 in the temperature interval from 1073 K to 1373 K (800 °C to 1100 °C) is investigated and compared to cast material. Weight gain is measured discontinuously at different oxidation temperatures and times. Analysis of oxidized samples is done via SEM and EDX-measurements. MIM samples exhibit homogeneous oxide layers with a thickness up to 4 µm. After processing by MIM, Inconel 713 exhibits lower weight gain and thinner oxide layers than MAR-M247.

Albert, Benedikt; Völkl, Rainer; Glatzel, Uwe

2014-09-01

358

10 CFR 1016.35 - Authority to reproduce Restricted Data.  

...false Authority to reproduce Restricted Data. 1016.35 Section 1016.35 Energy...PROVISIONS) SAFEGUARDING OF RESTRICTED DATA Control of Information § 1016.35 Authority to reproduce Restricted Data. Secret Restricted Data will...

2014-01-01

359

High dissemination of extended-spectrum ?-lactamase-producing Enterobacteriaceae in effluents from wastewater treatment plants.  

PubMed

Water environments play an important role in the dissemination of antibiotic-resistant bacteria among humans, animals and agricultural sources. In order to assess the spread of extended-spectrum ?-lactamase (ESBL)-producing Enterobacteriaceae, we analyzed 279 effluent samples from 21 wastewater treatment plants in Navarra (northern Spain). A total of 185 cefpodoxime-resistant bacteria were isolated on ChromID ESBL agar plates, with high predominance of Escherichia coli among isolated species (73%). ESBL production was determined by different methods, concluding its presence in 86.5% of the isolates by the combination disk test, 75.7% by double-disk synergy test and 73.5% by MicroScan(®) NM37 automated system. PCR and sequencing analysis showed that the predominant ?-lactamases (bla) genes were blaCTx-M (67.4%) followed by blaTEM (47%), blaSHV (17.4%) and blaOxA (8.3%); furthermore, two or more ?-lactamases genes were found in 34.9% of the isolates. The results demonstrate the high prevalence of ESBL-producing Enterobacteriaceae in effluent water from wastewater treatment plants and confirm the need to optimize current disinfection procedures and to improve management of wastewater in an effort to minimize reservoirs of resistant bacteria. Further studies are needed for examining the presence of these bacteria in other environments and for determining the potential dissemination routes of these resistances as well as their impact on human health. PMID:24651016

Ojer-Usoz, Elena; González, David; García-Jalón, Isabel; Vitas, Ana Isabel

2014-06-01

360

RAPID COMMUNICATION VARROA JACOBSONI DOES REPRODUCE IN WORKER  

E-print Network

) reported that Varroa jacobsoni greatly prefers drone over worker brood, and only reproduces in the drone brood of Apis cerana colonies in Sri Lanka and Indonesia. In Apis mellifera the mites also prefer drone cells, but can reproduce effectively in both worker and drone cells. The capacity to reproduce in worker

Paris-Sud XI, Université de

361

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. PMID:21283776

Langfelder, Peter; Luo, Rui; Oldham, Michael C.; Horvath, Steve

2011-01-01

362

Can global chemistry-climate models reproduce air quality extremes?  

NASA Astrophysics Data System (ADS)

We identify and characterize extreme ozone pollution episodes over the USA and EU through a novel analysis of ten years (2000-2010) of surface ozone measurements. An optimal interpolation scheme is developed to create grid-cell averaged values of surface ozone that can be compared with gridded model simulations. In addition, it also allows a comparison of two non-coincident observational networks in the EU. The scheme incorporates techniques borrowed from inverse distance weighting and Kriging. It uses all representative observational site data while still recognizing the heterogeneity of surface ozone. Individual, grid-cell level events are identified as an exceedance of historical percentile (10 worst days in a year, 97.3 percentile). A clustering algorithm is then used to construct the ozone episodes from the individual events. We then test the skill of the high-resolution (100 km) two-year (2005-2006) hindcast from the UCI global chemistry transport model in reproducing the events/episodes identified in the observations using the same identification criteria. Although the UCI CTM has substantial biases in surface ozone, we find that it has considerable skill in reproducing both individual grid-cell level extreme events and their connectedness in space and time with an overall skill of 24% (32%) for the US (EU). The grid-cell level extreme ozone events in both the observations and UCI CTM are found to occur mostly (~75%) in coherent, multi-day, connected episodes covering areas greater than 1000 x 1000 square km. In addition the UCI CTM has greater skill in reproducing these larger episodes. We conclude that even at relatively coarse resolution, global chemistry-climate models can be used to project major synoptic pollution episodes driven by large-scale climate and chemistry changes even with their known biases.

Schnell, J.; Prather, M. J.; Holmes, C. D.

2013-12-01

363

Chemical Fabrication Used to Produce Thin-Film Materials for High Power-to- Weight-Ratio Space Photovoltaic Arrays  

NASA Technical Reports Server (NTRS)

The key to achieving high specific power (watts per kilogram) space solar arrays is the development of a high-efficiency, thin-film solar cell that can be fabricated directly on a flexible, lightweight, space-qualified durable substrate such as Kapton (DuPont) or other polyimide or suitable polymer film. Cell efficiencies approaching 20 percent at AM0 (air mass zero) are required. Current thin-film cell fabrication approaches are limited by either (1) the ultimate efficiency that can be achieved with the device material and structure or (2) the requirement for high-temperature deposition processes that are incompatible with all presently known flexible polyimide or other polymer substrate materials. Cell fabrication processes must be developed that will produce high-efficiency cells at temperatures below 400 degrees Celsius, and preferably below 300 degress Celsius to minimize the problems associated with the difference between the coefficients of thermal expansion of the substrate and thin-film solar cell and/or the decomposition of the substrate.

Hepp, Aloysius F.; Rybicki, George C.; Raffaelle, Ryne P.; Harris, Jerry D.; Hehemann, David G.; Junek, William; Gorse, Joseph; Thompson, Tracy L.; Hollingsworth, Jennifer A.; Buhro, William E.

2000-01-01

364

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. PMID:23360451

2013-01-01

365

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

366

Effect of high pressure treatment on the survival of Shiga toxin-producing Escherichia coli in strawberry puree.  

PubMed

Most fresh produce, such as strawberries, receives minimal processing and is often eaten raw. Contamination of produce with pathogenic bacteria may occur during growth, harvest, processing, transportation, and storage (abuse temperature) and presents a serious public health risk. Strawberries have been implicated in an outbreak of Escherichia coli O157:H7 infection that sickened 15 people, including one death. Strawberries may also be contaminated by other serogroups of non-O157 Shiga toxin-producing E. coli (STEC), including O26, O45, O103, O111, O121 and O145, which have become known as the "Big Six" or "Top Six" non-O157 STECs. The objective of this research was to explore the potential application of high pressure processing (HPP) treatment to reduce or eliminate STECs in fresh strawberry puree (FSP). FSP, inoculated with a six-strain cocktail of the "Big Six" non-O157 STEC strains or a five-strain cocktail of E. coli O157:H7 in vacuum-sealed packages, were pressure-treated at 150, 250, 350, 450, 550, and 650 MPa (1 MPa = 10(6) N/m(2)) for 5, 15, and 30 min. HPP treatment, at 350 MPa for ?5 min, significantly reduced STECs in FSP by about 6-log CFU/g from the initial cell population of ca. 8-log CFU/g. Cell rupture, observed by scanning electron microscopy (SEM), demonstrated that the HPP treatments can be potentially used to control both non-O157 and O157:H7 STECs in heat sensitive products. PMID:24549194

Hsu, HsinYun; Sheen, Shiowshuh; Sites, Joseph; Huang, Lihan; Wu, James Swi-Bea

2014-06-01

367

Towards interoperable and reproducible QSAR analyses: Exchange of datasets  

PubMed Central

Background QSAR is a widely used method to relate chemical structures to responses or properties based on experimental observations. Much effort has been made to evaluate and validate the statistical modeling in QSAR, but these analyses treat the dataset as fixed. An overlooked but highly important issue is the validation of the setup of the dataset, which comprises addition of chemical structures as well as selection of descriptors and software implementations prior to calculations. This process is hampered by the lack of standards and exchange formats in the field, making it virtually impossible to reproduce and validate analyses and drastically constrain collaborations and re-use of data. Results We present a step towards standardizing QSAR analyses by defining interoperable and reproducible QSAR datasets, consisting of an open XML format (QSAR-ML) which builds on an open and extensible descriptor ontology. The ontology provides an extensible way of uniquely defining descriptors for use in QSAR experiments, and the exchange format supports multiple versioned implementations of these descriptors. Hence, a dataset described by QSAR-ML makes its setup completely reproducible. We also provide a reference implementation as a set of plugins for Bioclipse which simplifies setup of QSAR datasets, and allows for exporting in QSAR-ML as well as old-fashioned CSV formats. The implementation facilitates addition of new descriptor implementations from locally installed software and remote Web services; the latter is demonstrated with REST and XMPP Web services. Conclusions Standardized QSAR datasets open up new ways to store, query, and exchange data for subsequent analyses. QSAR-ML supports completely reproducible creation of datasets, solving the problems of defining which software components were used and their versions, and the descriptor ontology eliminates confusions regarding descriptors by defining them crisply. This makes is easy to join, extend, combine datasets and hence work collectively, but also allows for analyzing the effect descriptors have on the statistical model's performance. The presented Bioclipse plugins equip scientists with graphical tools that make QSAR-ML easily accessible for the community. PMID:20591161

2010-01-01

368

Discharge-produced plasma extreme ultraviolet (EUV) source and ultra high vacuum chamber for studying EUV-induced processes  

E-print Network

An experimental setup that directly reproduces Extreme UV-lithography relevant conditions for detailed component exposure tests is described. The EUV setup includes a pulsed plasma radiation source, operating at 13.5 nm; a debris mitigation system; collection and filtering optics; and an UHV experimental chamber, equipped with optical and plasma diagnostics. The first results, identifying the physical parameters and evolution of EUV-induced plasmas are presented. Finally, the applicability and accuracy of the in situ diagnostics is briefly discussed.

Dolgov, A; Abrikosov, A; Snegirev, E; Krivtsun, V M; Lee, C J; Bijkerk, F

2014-01-01

369

High-level expression and purification of recombinant human growth hormone produced in soluble form in Escherichia coli.  

PubMed

Human growth hormone (hGH) was one of the first recombinant proteins approved for the treatment of human growth disorders. Its small size (191 amino acids), possession of only 2 disulphide bonds and absence of posttranslational modifications make Escherichia coli the host of choice for its production on any scale. In this work, we have utilized an efficient T7 based expression system to produce high levels of soluble thioredoxin-hGH (Trx-hGH) fusion protein. We outline a relatively simple three step purification process employing two immobilized metal-affinity chromatography and one anion-exchange steps and removal of fusion partner by enterokinase cleavage yielding native hGH. The ability of cell populations to produce quantities of up to 1 g/L of the soluble Trx-hGH fusion protein has been tested in flask cultivations as well as in batch and fed-batch bioreactor runs. The sequence and structure of derived hGH were confirmed by mass spectrometry and circular dichroism and its native function, to induce cell proliferation, was confirmed by employing a Nb2 cell line proliferation assay. PMID:24859479

Levarski, Zdenko; Šoltýsová, Andrea; Krahulec, Ján; Stuchlík, Stanislav; Tur?a, Ján

2014-08-01

370

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

371

Mutation in Serratia marcescens AmpC ?-Lactamase Producing High-Level Resistance to Ceftazidime and Cefpirome  

PubMed Central

Starting from a clinical isolate of Serratia marcescens that produced a chromosomally encoded AmpC ?-lactamase inducibly, we isolated by stepwise selection two laboratory mutants that showed high levels of resistance to some cephalosporins. The 98R mutant apparently overproduced the unaltered ?-lactamase constitutively, but the 520R mutant produced an altered enzyme, also constitutively. Ceftazidime and cefpirome MICs for the 520R mutant were much higher (512 and 64 ?g/ml, respectively) than those for the 98R mutant (16 and 16 ?g/ml, respectively). Yet the MICs of cephaloridine and piperacillin for the 520R mutant were four- to eightfold lower than those for the 98R mutant. Cloning and sequencing of the ampC alleles showed that in the 520R mutant enzyme, the Thr64 residue, about two turns away from the active-site serine, was mutated to isoleucine. This resulted in a >1,000-fold increase in the catalytic efficiency (kcat/Km) of the mutated AmpC enzyme toward ceftazidime, whereas there was a >10-fold decrease in the efficiency of the mutant enzyme toward cefazolin and cephaloridine. The outer membrane permeability of the 520R strain to cephalosporins was also less than in the 98R strain, and the alteration of the kinetic properties of the AmpC enzyme together with this difference in permeability explained quantitatively the resistance levels of both mutant strains to most agents studied. PMID:11451693

Raimondi, Alessandro; Sisto, Francesca; Nikaido, Hiroshi

2001-01-01

372

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

373

Residential wire codes: reproducibility and relation with measured magnetic fields  

PubMed Central

OBJECTIVES: To investigate the reproducibility of wire codes to characterise residential power line configurations and to determine the extent to which wire codes provide a proxy measure of residential magnetic field strength in a case-control study of childhood leukaemia conducted in nine states within the United States. METHODS: Misclassification of wire codes was assessed with independent measurements by two technicians for 187 residences. The association between categories of wire code and measured level of magnetic field was evaluated in 858 residences with both a wire code measurement and a 24 hour measurement of the magnetic field in the bedroom. The strength of the association between category of wire code and risk of leukaemia was examined in two regions with different average levels of magnetic field in homes with high categories of wire code. RESULTS: The reproducibility of any of three different classifications of wire codes was excellent (kappa > or = 0.89). Mean and median magnetic fields, and the percentage of homes with high magnetic fields increased with increasing category for each of the wire code classification schemes. The size of the odds ratios for risk of leukaemia and high categories of wire code did not reflect the mean levels of the magnetic field in those categories in two study regions. CONCLUSION: Misclassification of categories of wire code is not a major source of bias in the study. Wire codes provide a proxy measure of exposure to residential magnetic fields. If magnetic fields were a risk factor for leukaemia, however, there would be some attenuation of risk estimates based on wire codes because of misclassification of exposure to magnetic fields at both extremes of the wire code range. The lack of an association between high categories of wire code and risk of leukaemia cannot be explained by a failure of the wire code classification schemes to estimate exposure to magnetic fields in the study area.   PMID:9764111

Tarone, R. E.; Kaune, W. T.; Linet, M. S.; Hatch, E. E.; Kleinerman, R. A.; Robison, L. L.; Boice, J. D.; Wacholder, S.

1998-01-01

374

High throughput quantitative expression screening and purification applied to recombinant disulfide-rich venom proteins produced in E. coli.  

PubMed

Escherichia coli (E. coli) is the most widely used expression system for the production of recombinant proteins for structural and functional studies. However, purifying proteins is sometimes challenging since many proteins are expressed in an insoluble form. When working with difficult or multiple targets it is therefore recommended to use high throughput (HTP) protein expression screening on a small scale (1-4 ml cultures) to quickly identify conditions for soluble expression. To cope with the various structural genomics programs of the lab, a quantitative (within a range of 0.1-100 mg/L culture of recombinant protein) and HTP protein expression screening protocol was implemented and validated on thousands of proteins. The protocols were automated with the use of a liquid handling robot but can also be performed manually without specialized equipment. Disulfide-rich venom proteins are gaining increasing recognition for their potential as therapeutic drug leads. They can be highly potent and selective, but their complex disulfide bond networks make them challenging to produce. As a member of the FP7 European Venomics project (www.venomics.eu), our challenge is to develop successful production strategies with the aim of producing thousands of novel venom proteins for functional characterization. Aided by the redox properties of disulfide bond isomerase DsbC, we adapted our HTP production pipeline for the expression of oxidized, functional venom peptides in the E. coli cytoplasm. The protocols are also applicable to the production of diverse disulfide-rich proteins. Here we demonstrate our pipeline applied to the production of animal venom proteins. With the protocols described herein it is likely that soluble disulfide-rich proteins will be obtained in as little as a week. Even from a small scale, there is the potential to use the purified proteins for validating the oxidation state by mass spectrometry, for characterization in pilot studies, or for sensitive micro-assays. PMID:25146501

Saez, Natalie J; Nozach, Hervé; Blemont, Marilyne; Vincentelli, Renaud

2014-01-01

375

Reproducibility of an aerobic endurance test for nonexpert swimmers  

PubMed Central

Background: This study aimed to verify the reproduction of an aerobic test to determine nonexpert swimmers’ resistance. Methods: The sample consisted of 24 male swimmers (age: 22.79 ± 3.90 years; weight: 74.72 ± 11.44 kg; height: 172.58 ± 4.99 cm; and fat percentage: 15.19% ± 3.21%), who swim for 1 hour three times a week. A new instrument was used in this study (a Progressive Swim Test): the swimmer wore an underwater MP3 player and increased their swimming speed on hearing a beep after every 25 meters. Each swimmer’s heart rate was recorded before the test (BHR) and again after the test (AHR). The rate of perceived exertion (RPE) and the number of laps performed (NLP) were also recorded. The sample size was estimated using G*Power software (v 3.0.10; Franz Faul, Kiel University, Kiel, Germany). The descriptive values were expressed as mean and standard deviation. After confirming the normality of the data using both the Shapiro–Wilk and Levene tests, a paired t-test was performed to compare the data. The Pearson’s linear correlation (r) and intraclass coefficient correlation (ICC) tests were used to determine relative reproducibility. The standard error of measurement (SEM) and the coefficient of variation (CV) were used to determine absolute reproducibility. The limits of agreement and the bias of the absolute and relative values between days were determined by Bland–Altman plots. All values had a significance level of P < 0.05. Results: There were significant differences in AHR (P = 0.03) and NLP (P = 0.01) between the 2 days of testing. The obtained values were r > 0.50 and ICC > 0.66. The SEM had a variation of ±2% and the CV was <10%. Most cases were within the upper and lower limits of Bland–Altman plots, suggesting correlation of the results. The applicability of NLP showed greater robustness (r and ICC > 0.90; SEM < 1%; CV < 3%), indicating that the other variables can be used to predict incremental changes in the physiological condition of swimmers. Conclusion: The Progressive Swim Test for nonexpert swimmers produces comparable results for noncompetitive swimmers with a favorable degree of reproducibility, thus presenting possible applications for researching the physiological performance of nonexpert swimmers. PMID:23055740

Veronese da Costa, Adalberto; Costa, Manoel da Cunha; Carlos, Daniel Medeiros; Guerra, Luis Marcos de Medeiros; Silva, Antonio Jose; Barbosa, Tiago Manoel Cabral dos Santos

2012-01-01

376

Development of a novel articulator that reproduced jaw movement with six-degree-of-freedom  

Microsoft Academic Search

A novel robotic articulator that reproduced a six-degree-of-freedom jaw movement was developed and tested. A precise six-axis micro-positioning stage was employed for this articulator. A high-resolution jaw-tracking device measured the functional jaw movement of the patient and a six-axis micro-positioning stage reproduced recorded jaw movement data. A full veneer crown restoration was fabricated with this articulator system. A working cast

Keisuke Nishigawa; Toyoko Satsuma; Shuji Shigemoto; Eiichi Bando; Masanori Nakano; Osamu Ishida

2007-01-01

377

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.

378

Chemical immobilization of crosslinked polymeric ionic liquids on nitinol wires produces highly robust sorbent coatings for solid-phase microextraction.  

PubMed

Super elastic nitinol (NiTi) wires were exploited as highly robust supports for three distinct crosslinked polymeric ionic liquid (PIL)-based coatings in solid-phase microextraction (SPME). The oxidation of NiTi wires in a boiling (30%w/w) H2O2 solution and subsequent derivatization in vinyltrimethoxysilane (VTMS) allowed for vinyl moieties to be appended to the surface of the support. UV-initiated on-fiber copolymerization of the vinyl-substituted NiTi support with monocationic ionic liquid (IL) monomers and dicationic IL crosslinkers produced a crosslinked PIL-based network that was covalently attached to the NiTi wire. This alteration alleviated receding of the coating from the support, which was observed for an analogous crosslinked PIL applied on unmodified NiTi wires. A series of demanding extraction conditions, including extreme pH, pre-exposure to pure organic solvents, and high temperatures, were applied to investigate the versatility and robustness of the fibers. Acceptable precision of the model analytes was obtained for all fibers under these conditions. Method validation by examining the relative recovery of a homologous group of phthalate esters (PAEs) was performed in drip-brewed coffee (maintained at 60 °C) by direct immersion SPME. Acceptable recoveries were obtained for most PAEs in the part-per-billion level, even in this exceedingly harsh and complex matrix. PMID:25150693

Ho, Tien D; Toledo, Bruna R; Hantao, Leandro W; Anderson, Jared L

2014-09-16

379

Measurements of electrical resistivity of heavy ion beam produced high energy density matter: Latest results for lead and tungsten  

NASA Astrophysics Data System (ADS)

The high-intensity heavy ion beams provided by the accelerator facilities of the Gesellschaft für Schwerionenforschung (GSI) Darmstadt are an excellent tool to produce large volumes of high energy density (HED) matter. Thermophysical and transport properties of HED matter states are of interest for fundamental as well as for applied research. During the last few years development of new diagnostic techniques allowed for a series of measurements of the electrical resistivity of heavy ion beam generated HED matter. In this report we present the most recent results on electrical resistivity of HED matter at GSI. The experiments on which we report have been performed with targets consisting of tungsten wires and lead foils, respectively. Uranium and argon beam pulses with durations of a few hundred ns, intensities of about 2×109 and 1×1011 ions/bunch, respectively, and an initial ion energy of 300-350 A MeV have been used as a driver. An energy density deposition of about 1 kJ/g has been achieved by focusing the ion beam down to 1 mm FWHM or less.

Udrea, Serban; Ternovoi, Vladimir; Shilkin, Nikolay; Fertman, Alexander; Fortov, Vladimir E.; Hoffmann, Dieter H. H.; Hug, Alexander; Kulish, Michail I.; Mintsev, Victor; Ni, Pavel; Nikolaev, Dmitry; Tahir, Naeem A.; Turtikov, Vladimir; Varentsov, Dmitry; Yuriev, Denis

2007-07-01

380

Ion-Ion Reactions with Fixed-Charge Modified Proteins to Produce Ions in a Single, Very High Charge State  

PubMed Central

Electrospray ionization (ESI) of denatured proteins produces a mass spectrum with a broad distribution of multiply charged ions. Attaching fixed positive charges, specifically quaternary ammonium groups, to proteins at their carboxylic acid groups generates substantially higher charge states compared to the corresponding unmodified proteins in positive-mode ESI. Ion-ion reactions of these modified proteins with reagent anions leads to charge reduction by proton transfer. These proton transfer reactions cannot remove charge from the quaternary ammonium groups, which do not have a proton to transfer to the anion. Thus, one might expect charge reduction to stop at a single charge state equal to the number of fixed charges on the modified protein. However, ion-ion reactions yield charge states lower than this number of fixed charges due to anion attachment (adduction) to the proteins. Charge reduction via ion-molecule reactions involving gas-phase bases also give adducts on the modified protein ions in low charge states. Such adducts are avoided by keeping the ions in charge states well above the number of fixed charges. In the present work protein ions were selectively “parked” within an ion trap mass spectrometer in a high charge state by mild radiofrequency excitation that dramatically slows their ion-ion reaction rate—a technique termed “ion parking”. The combination of ion parking with the fixed-charge modified proteins permits generation of a large population of ions in a single, very high charge state. PMID:19802328

Frey, Brian L.; Krusemark, Casey J.; Ledvina, Aaron R.; Coon, Joshua J.; Belshaw, Peter J.

2008-01-01

381

Accuracy and reproducibility of probe forces during simulated periodontal pocket depth measurements  

PubMed Central

Aim The aim of the present study was to measure the accuracy and reproducibility of probe forces in simulated assessments of periodontal pocket depth. The study included experienced and inexperienced examiners and used manual and pressure-sensitive probes. Materials and methods Sixty-one participants were divided into seven groups and asked to probe selected anterior and posterior sites with three different probes (Williams 14W, Chapple UB-CF-15, and Vivacare TPS probes). The model was positioned on a digital electronic balance to measure force, which was recorded initially and after 15 min. Probe preferences were recorded. Accuracy was measured by comparing to a standardized 25 g force, and reproducibility was calculated for all duplicate measurements. Results The Vivacare probe produced the most accurate and most reproducible forces, whereas the Williams probe produced the least accurate and least reproducible forces. Probe forces were lighter at anterior sites compared to posterior sites at baseline. Probe forces were reduced at both sites after 15 min compared to baseline. Conclusions Vivacare TPS periodontal probes are more accurate and reproducible than Chapple and Williams probes. Many clinicians in this study preferred the Chapple probe.

Al Shayeb, K.N.; Turner, W.; Gillam, D.G.

2014-01-01

382

Reproduced from: 3 November 2004: B24  

E-print Network

: social insects are highly altruistic. Sometimes, it is dramatic, such as a worker bee's suicidal a clever ploy, a genetic subterfuge which advances the genetic interests of the "altruist." For example kin groups. In the case of bees and ants, their super- altruistic behavior is favored by a genetic

Turner, Scott

383

Accurate, reproducible measurement of blood pressure.  

PubMed

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. PMID:2192791

Campbell, N R; Chockalingam, A; Fodor, J G; McKay, D W

1990-07-01

384

Educating for anti?racism: producing and reproducing race and power in a university classroom  

Microsoft Academic Search

In this paper I explore some of the issues associated with teaching about race, culture, and ethnicity in a psychology program. These curriculum initiatives are part of a broader agenda of raising awareness about racialised oppression and exclusion and contributing to the development of ways of researching and practicing psychology that are transformative and culturally sensitive. I overview the broader

Christopher C. Sonn

2008-01-01

385

Educating for Anti-Racism: Producing and Reproducing Race and Power in a University Classroom  

ERIC Educational Resources Information Center

In this paper I explore some of the issues associated with teaching about race, culture, and ethnicity in a psychology program. These curriculum initiatives are part of a broader agenda of raising awareness about racialised oppression and exclusion and contributing to the development of ways of researching and practicing psychology that are…

Sonn, Christopher C.

2008-01-01

386

Succinic acid-producing biofilms of Actinobacillus succinogenes: reproducibility, stability and productivity.  

PubMed

Continuous anaerobic fermentations were performed in a biofilm reactor packed with Poraver® beads. Dilution rates (D) varied between 0.054 and 0.72 h(-1), and D-glucose and CO2 gas were used as carbon substrates. Steady-state conditions were shown to be repeatable and independent of the operational history. Production stability was achieved over periods exceeding 80 h at values of D below 0.32 h(-1). In these situations, steady-state variation (expressed as fluctuations in NaOH neutralisation flow rates) exhibited a standard deviation of less than 5 % while no indication of biofilm deactivation was detected. The total biomass amount was found to be independent of the dilution rate with an average dry concentration of 23.8?±?2.9 g L(-1) obtained for all runs. This suggests that the attachment area controls the extent of biofilm accumulation. Specific succinic acid (SA) productivities, based on the total biomass amount, exhibited a substantial decrease with decreasing D. An SA volumetric productivity of 10.8 g L(-1) h(-1) was obtained at D?=?0.7 h(-1)-the highest value reported to date in Actinobacillus succinogenes fermentations. SA yields on glucose increased with decreasing D, with a yield of 0.90?±?0.01 g g(-1) obtained at a D of 0.054 h(-1). Production of formic acid approached zero with decreasing D, while the succinic to acetic acid ratio increased with decreasing D, resulting in an increasing SA yield on glucose. PMID:24816619

Maharaj, K; Bradfield, M F A; Nicol, W

2014-09-01

387

Doppler flow velocity waveforms in the fetal cardiac outflow tract: reproducibility of waveform recording and analysis.  

PubMed

Reproducibility of flow velocity waveform recording and analysis was studied at fetal cardiac level (ductus arteriosus, pulmonary artery and ascending aorta) in 42 normal pregnancies. The flow velocity parameters studied were the peak systolic velocity (PSV), acceleration time (ACT), acceleration velocity (ACV), average velocity (AV) and flow velocity integral (FVI). In each patient, two consecutive measurements were performed (time delay 15 min) and of each measurement two hardcopies were analysed. A high reproducibility was achieved for the PSV, AV and FVI in all vessels studied; the coefficients of variation between readings of hardcopies were less than or equal to 3%, and the coefficients of variation between tests within patients were less than or equal to 7%. A moderate reproducibility was achieved for the ACT in the ascending aorta and pulmonary artery; the variation between tests was large for the ductus arteriosus. The reproducibility of the ACV was poor. PMID:1962360

Groenenberg, I A; Hop, W C; Wladimiroff, J W

1991-01-01

388

Effect of surface produced secondary electrons on the sheath structure induced by high-power microwave window breakdown  

NASA Astrophysics Data System (ADS)

Dielectric window breakdown, whose mechanism is not thoroughly understood, is a major factor of limiting the transmission and radiation of high-power microwave on the order of 1 GW. In this paper, a one-dimensional fluid-like sheath model is developed to investigate the sheath structures formed at different gas pressures. The dominant processes during the surface flashover are isolated by this model. In vacuum, electron multipactor is self-sustained by secondary electron emission, a positive space-charge potential is formed on the dielectric surface. With increasing gas pressure, electron-neutral ionization prevails against secondary electron emission. The multipactor effect is suppressed by the shielding of plasma electrons. This leads to the sheath potential changing gradually from a positive space-charge potential to a negative space-charge potential. For argon gas pressure lower than 14 Torr, the sheath is space charge limited. A potential minimum could be formed in front of the dielectric which traps secondary electrons emitted from the wall. With the higher argon gas pressure, the number density of ions becomes comparable to that of electrons, all surface produced electrons are accelerated toward the presheath region. Therefore, the normal sheath is formed and the resulting surface flashover on the dielectric surface becomes rf-driven volumetric breakdown.

Cheng, Guoxin; Liu, Lie

2011-03-01

389

Heterotrophic high cell-density fed-batch cultures of the phycocyanin-producing red alga Galdieria sulphuraria.  

PubMed

Growth and phycocyanin production in batch and fed-batch cultures of the microalga Galdieria sulphuraria 074G, which was grown heterotrophically in darkness on glucose, fructose, sucrose, and sugar beet molasses, was investigated. In batch cultures, specific growth rates and yields of biomass dry weight on the pure sugars were 1.08-1.15 day-1 and 0.48-0.50 g g-1, respectively. They were slightly higher when molasses was the carbon source. Cellular phycocyanin contents during the exponential growth phase were 3-4 mg g-1 in dry weight. G. sulphuraria was able to tolerate concentrations of glucose and fructose of up to 166 g L-1 (0.9 M) and an ammonium sulfate concentration of 22 g L-1 (0.17 M) without negative effects on the specific growth rate. When the total concentration of dissolved substances in the growth medium exceeded 1-2 M, growth was completely inhibited. In carbon-limited fed-batch cultures, biomass dry weight concentrations of 80-120 g L-1 were obtained while phycocyanin accumulated to concentrations between 250 and 400 mg L-1. These results demonstrate that G. sulphuraria is well suited for growth in heterotrophic cultures at very high cell densities, and that such cultures produce significant amounts of phycocyanin. Furthermore, the productivity of phycocyanin in the heterotrophic fed-batch cultures of G. sulphuraria was higher than is attained in outdoor cultures of Spirulina platensis, where phycocyanin is presently obtained. PMID:15723314

Schmidt, Rikke Ankerstjerne; Wiebe, Marilyn G; Eriksen, Niels Thomas

2005-04-01

390

Microstructure and mechanical properties of Nb15Al10Ti alloy produced by mechanical alloying and high temperature processing.  

PubMed

In this work, an Nb15Al10Ti alloy produced by mechanical alloying was investigated. The milling of elemental powders of Nb, Al as well as TiAl intermetallic phase resulted in the formation of homogenous niobium solid solution, Nb(ss), and refinement of powder particles. Powder after milling was consolidated by conventional hot pressing at 1300 degrees C under pressure of 25 MPa as well as by hot isostatic pressing at 1200 degrees C under pressure of 1 GPa. Microstructure of consolidated material was examined by transmission electron microscopy, scanning electron microscopy and X-ray diffraction. Materials after consolidation were composed of three phases: niobium solid solution Nb(ss), Nb(3)Al intermetallic phase and titanium oxide dispersoid TiO. The analysis of the mechanical properties indicated that both refinement of microstructure as well as introduction of ductile Nb(ss) into the microstructure contributed to very high yield strength and fracture toughness satisfactory for this strength. PMID:20500425

Rozmus, M; Blicharski, M; Dymek, S

2010-03-01

391

High-coverage gene expression profiling analysis of the cellulase-producing fungus Acremonium cellulolyticus cultured using different carbon sources.  

PubMed

The gene expression of a cellulase-producing fungus, Acremonium cellulolyticus, was investigated after culturing with three different carbon sources: glycerol, lactose, and Solka-Floc powdered cellulose (SF). High-coverage gene expression profiling (HiCEP) analysis, a method requiring no prior sequence knowledge, was used to screen genes upregulated at the early stage of cellulase production. SF was used as a strong inducer of cellulase production, lactose was used as an inducer of the expression of cellulase genes at the early stage of the culture, and glycerol was used as a negative control. Approximately 15,000 transcript-derived fragments (TDFs) were detected in each sample prepared from the culture grown for 16 h. Based on the expression profiles of the cultured cells, 36 fragments upregulated in both the SF and lactose cultures were selected and sequenced. The deduced gene products of 31 TDFs were likely related to biomass degradation, sugar metabolism, transcriptional regulation, protein modification and metabolism, cell wall recycling, fatty acid and polyketide biosynthesis, and other functions. Quantitative real-time reverse-transcriptase polymerase chain reaction analysis verified that almost all of the transcripts obtained by HiCEP analysis were upregulated in the SF and lactose cultures grown for 18 h. Some of the TDFs in the SF culture were further upregulated over the course of 72 h. The gene products from these TDFs would provide insight into improving the cellulase productivity of A. cellulolyticus. PMID:23306646

Hideno, Akihiro; Inoue, Hiroyuki; Fujii, Tatsuya; Yano, Shinichi; Tsukahara, Kenichiro; Murakami, Katsuji; Yunokawa, Harunobu; Sawayama, Shigeki

2013-06-01

392

Type of new Chinese-produced high-speed camera and its utilization in detonation physics experiments  

NASA Astrophysics Data System (ADS)

This paper introduces the technological capability and special features of the new, domestically produced, Type SJZ-15 high-speed rotating mirror scanning camera and its utilization in detonation physics experiments. The camera uses an axial flow gas turbine and a two-stage internal blower for cooling. The turbine and blower use the same group of nozzles. The structure is simple, has good axial balance, and improves the cooling capability of the driving bearing housing. The two ends of the rotating mirror use three elastic bearing supporters. The axial bearings have 0-type elastic rubber balls, which are automatically centered and absorb vibration very well. The rotating mirror does not use an axial vacuum system, but the picture quality is excellent. The first objective lens Fujica type and permits use as a split-range camera. The operation handles are located on the same side of the camera. The operation handles for the rotating mirror and the main objective lens are not as convenient as the micrometer adjustment. Detonation experimental tests, technology evaluations, and actual usage prove the operation is simple and reliable, the quality of optical image formation is excellent, the light strength is appropriate, and it is an instrument of comparatively great potential.

Sang, Y.

393

Orthodontic bracket shear bond strengths produced by two high-power light-emitting diode modes and halogen light.  

PubMed

The aim of this in vitro study was to compare the shear bond strength of orthodontic brackets cured with two different high-power light-emitting diode (LED) polymerization modes with traditional halogen polymerization. A total of forty-five extracted human premolar teeth were randomly divided into three groups. Each group consisted of 15 teeth mounted in an acrylic block. Following a standard enamel etching protocol, orthodontic brackets were cured on the first group of teeth with fast-mode LED, the second group with soft-start mode LED, and on the last group with a halogen light. After bonding, the shear bond strengths of the brackets were tested with a universal testing machine. The results showed that brackets cured with soft-start mode LED produced the highest shear bond strengths (23.86 +/- 6.20 MPa). No significant difference was found between fast-mode LED (17.14 +/- 5.75 MPa) and the halogen group (17.38 +/- 5.41 MPa) (P > .05). The LED is effective for bonding metal brackets to teeth, and the soft-start mode gives higher bond strengths than the fast mode. PMID:16283816

Türkkahraman, Hakan; Küçüke?men, H Cenker

2005-09-01

394

Lateralization produced by interaural temporal and intensitive disparities of high-frequency, raised-sine stimuli: Data and modeling  

PubMed Central

An acoustic pointing task was used to measure extents of laterality produced by combinations of ongoing envelope-based interaural temporal disparities (ITDs) and interaural intensitive disparities (IIDs) of 4-kHz-centered raised-sine stimuli [Bernstein and Trahiotis, J. Acoust. Soc. Am. 125, 3234–3242 (2009),] while varying, parametrically, their peakedness, depth of modulation, and frequency of modulation. The study was designed to assess whether IIDs act as “weights” within the putative “binaural display” at high spectral frequencies (where the envelopes convey ITD-information) as appears to be the case at low spectral frequencies (where the waveforms, i.e., fine-structure and envelopes, convey ITD-information). The data indicate that envelope-based IIDs do principally act as weights and that they appear to exert their influence on lateral position independently of the influence of ITDs. Quantitative analyses revealed that an augmented form of the cross-correlation-based “position-variable” model of Stern and Shear [J. Acoust. Soc. Am. 100, 2278–2288 (1996)] accounted for 94% of the variance in the data. This success notwithstanding, for a small subset of the data, predictions could be improved by assuming that the listeners utilized information within auditory filters having center frequencies above 4 kHz. PMID:22280602

Bernstein, Leslie R.; Trahiotis, Constantine

2012-01-01

395

High-resolution TEM Studies of Carbon Nanotubes and Catalyst Nanoparticles Produced During CVD from Metal Multilayer Films  

NASA Astrophysics Data System (ADS)

The structure of single-wall and multiwall carbon nanotubes and associated metal catalyst nanoparticles produced during chemical vapor deposition from multilayered metal films deposited on Si and Mo substrates were studied by high-resolution TEM and EDS. Electron beam-evaporated metal multilayer films (e.g. Al-Fe-Mo, typically 11-50 nm total thickness) roughen upon heat treatment to form a variety of catalyst particle sizes suitable for carbon nanotube growth by chemical vapor deposition using acetylene, hydrogen, and argon flow gases. This study investigates these nanoparticles, the type of nanotubes grown, their wall, tip, and basal structures, as well as the associated amounts of amorphous carbon deposited on their walls in different temperature and pressure ranges. Mixtures of SWNT and MWNT are found even for low growth temperatures (650-700 C), while rapid growth of vertically-aligned multiwall nanotubes (VA-MWNTs) predominate in a narrow temperature range at a given pressure. Arrested growth experiments were performed to determine the time periods for SWNT vs. MWNT growth. The nature of the catalyst nanoparticles, their support structure, and insights on the mechanisms of growth will be discussed.

Howe, Jane Y.; Puretzky, Alex A.; Geohegan, David B.; Cui, Hongtao; Eres, Varela; Maria, Alex A.; Lowndes, Douglas H.

2003-03-01

396

Four Star Greenhouse has been producing high quality garden products since 1977 and is the largest partner/supplier of the nationally recognized #1 plant brand Proven Winners.  

E-print Network

Four Star Greenhouse has been producing high quality garden products since of independent garden centers. As a team member of Four Star Greenhouse, you will join the Four Star Greenhouse website to view the complete job description at http

397

Trace elements determination in high salinity petroleum produced formation water by high-resolution continuum source graphite furnace atomic absorption spectrometry after matrix separation using Chelex-100® resin  

NASA Astrophysics Data System (ADS)

This study describes a procedure used for the determination of trace metals (Co, Cu, Mn, Ni and Pb) in high salinity petroleum produced formation water (PFW) employing high-resolution continuum source graphite furnace atomic absorption spectrometry for detection and Chelex-100® resin for matrix elimination and analytes preconcentration. Using 15.0 mL of PFW for the separation/preconcentration, detection limits of 0.006, 0.07, 0.03, 0.08 and 0.02 ?g L- 1 were obtained for Co, Cu, Mn, Ni and Pb, respectively. The accuracy of the proposed method was evaluated by analyzing three seawater certified reference materials and by recovery tests, and the data indicate that the methodology can be successfully applied to this kind of samples. The precision values, expressed as relative standard deviation (% RSD, n = 10) for 2.0 ?g L- 1, were found to be 3.5, 4.0, 9.0, 5.3 and 5.9 for Co, Cu, Mn, Ni and Pb, respectively. The proposed procedure was applied for the determination of these metals in medium and high salinity PFW samples obtained from Brazilian offshore petroleum exploration platforms.

Freire, Aline Soares; Santelli, Ricardo Erthal

2012-05-01

398

Feasibility of producing a short, high energy s-band linear accelerator using a klystron power source  

SciTech Connect

Purpose: To use a finite-element method (FEM) model to study the feasibility of producing a short s-band (2.9985 GHz) waveguide capable of producing x-rays energies up to 10 MV, for applications in a linac-MR, as well as conventional radiotherapy. Methods: An existing waveguide FEM model developed by the authors' group is used to simulate replacing the magnetron power source with a klystron. Peak fields within the waveguide are compared with a published experimental threshold for electric breakdown. The RF fields in the first accelerating cavity are scaled, approximating the effect of modifications to the first coupling cavity. Electron trajectories are calculated within the RF fields, and the energy spectrum, beam current, and focal spot of the electron beam are analyzed. One electron spectrum is selected for Monte Carlo simulations and the resulting PDD compared to measurement. Results: When the first cavity fields are scaled by a factor of 0.475, the peak magnitude of the electric fields within the waveguide are calculated to be 223.1 MV/m, 29% lower than the published threshold for breakdown at this operating frequency. Maximum electron energy increased from 6.2 to 10.4 MeV, and beam current increased from 134 to 170 mA. The focal spot FWHM is decreased slightly from 0.07 to 0.05 mm, and the width of the energy spectrum increased slightly from 0.44 to 0.70 MeV. Monte Carlo results show d{sub max} is at 2.15 cm for a 10 Multiplication-Sign 10 cm{sup 2} field, compared with 2.3 cm for a Varian 10 MV linac, while the penumbral widths are 4.8 and 5.6 mm, respectively. Conclusions: The authors' simulation results show that a short, high-energy, s-band accelerator is feasible and electric breakdown is not expected to interfere with operation at these field strengths. With minor modifications to the first coupling cavity, all electron beam parameters are improved.

Baillie, Devin [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Aubin, J. St. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Steciw, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

2013-04-15

399

Reproducibility of pre-syncopal responses to repeated orthostatic challenge  

NASA Astrophysics Data System (ADS)

Aims: To study individual patterns of hemodynamic adjustments in subjects reaching orthostatically induced presyncope and to observe whether these are reproducible across three runs. Procedures and methods: 10 healthy young males were subjected to extreme cardiovascular stress three times: Graded orthostatic stress (GOS), consisting of head-up tilt combined with lower body negative pressure, was used to achieve a pre-syncopal end-point. All test runs were separated by two week intervals. Orthostatic effects on cardiac and vascular function were continuously monitored and standing times noted. Results: Across the group, heart rate (HR) increased 112 percent, while mean arterial blood pressure dropped by 15 percent, pulse pressure by 36 percent, and stroke volume index by 51 percent on average from supine control to presyncope. Repetitions of the orthostatic protocols did not influence standing times of test persons from the 1st to the 3rd trial (15 plus minus 6 to 17 plus minus 7 min). Some individuals responded either with an increase in HR only, while the others with combined HR and total peripheral resistance increase, albeit shortly, and this individual specifc pattern was observed across the three runs of combined GOS. Conclusion: Strategies for maintaining blood pressure in response to central hypovolemia in subjects induced by orthostatic stress are different between subjects. However, the same individual specific hemodynamic mechanism is employed each time to maintain the blood pressure when reconfronted by this stress. Individual patterns of hemodynamic adjustments to orthostatic stress are highly reproducible when these subjects reach pre-syncope three times.

Goswami, Nandu; Grasser, Erik; Roessler, Andreas; Hinghofer-Szalkay, Helmut

400

Can the Nanoflare Model Reproduce Observed Emissions?  

NASA Technical Reports Server (NTRS)

All theories that attempt to explain the high temperatures observed in the solar corona are based on short bursts of energy release. The intensities and velocities measured in the core of an active, however, can be steady over many hours of observation. One heating scenario that has been proposed to reconcile such observations with models is the "long nanoflare storm," where short duration heating events occur infrequently on many sub-resolutions strands. In this Letter, we examine the emission measure distribution predicted for such a heating scenario by modeling an arcade of strands in an active region core. Comparisons of the computed emission measure distributions with recent observations indicate that that the long nanoflare storm scenario implies much more 1 MK emission than is actually observed for all plausible combinations of loop lengths, heating rates, and abundances. We conjecture that if the plasma had super coronal abundances, the model may be able to match the observations at low temperatures.

Mulu-Moore, Fana M.; Winebarger, Amy R.; Warren, Harry P.

2011-01-01

401

Anaerobic baffled reactor (ABR) for treating heavy oil produced water with high concentrations of salt and poor nutrient  

Microsoft Academic Search

The start-up and operational performance (total 212 days, including the start-up of 164 days) of an anaerobic baffled reactor (ABR), which is used to treat heavy oil produced water, was studied without the temperature control. Inoculums were mixtures of acclimated sediment taken from a heavy oil produced water treatment plant and digested sludge from a sewage wastewater treatment plant. The

G. D. Ji; T. H. Sun; J. R. Ni; J. J. Tong

2009-01-01

402

Ruggedness and reproducibility of the MBEC biofilm disinfectant efficacy test  

E-print Network

Ruggedness and reproducibility of the MBEC biofilm disinfectant efficacy test A.E. Parker a,b, , D.K. Walker a , D.M. Goeres a , N. Allan c , M.E. Olson c , A. Omar c a Center for Biofilm Engineering April 2014 Available online 9 May 2014 Keywords: Biofilm Ruggedness Reproducibility The MBECTM

Parker, Albert E.

403

Interobserver reproducibility of Gleason grading of prostatic carcinoma: Urologic pathologists  

Microsoft Academic Search

Gleason grading is now the most widely used grading system for prostatic carcinoma in the United States. However, there are only a few studies of the interobserver reproducibility of this system, and no extensive study of interobserver reproducibility among a large number of experienced urologic pathologists exists. Forty-six needle biopsies containing prostatic carcinoma were assigned Gleason scores by 10 urologic

William C Allsbrook; Kathy A Mangold; Maribeth H Johnson; Mahul B Amin; David G Bostwick; Peter A Humphrey; Edward C Jones; Victor E Reuter; Wael Sakr; Isabell A Sesterhenn; Patricia Troncoso; Thomas M Wheeler; Jonathan I Epstein

2001-01-01

404

Reproducing kernel element method. Part I: Theoretical formulation  

E-print Network

Reproducing kernel element method. Part I: Theoretical formulation Wing Kam Liu a,*, Weimin Han b, collectively called the reproducing kernel element method (RKEM). The central idea in the development of the new method is to combine the strengths of both finite element methods (FEM) and meshfree methods. Two

Li, Shaofan

405

Reproducibility of Vibrionaceae population structure in coastal bacterioplankton  

PubMed Central

How reproducibly microbial populations assemble in the wild remains poorly understood. Here, we assess evidence for ecological specialization and predictability of fine-scale population structure and habitat association in coastal ocean Vibrionaceae across years. We compare Vibrionaceae lifestyles in the bacterioplankton (combinations of free-living, particle, or zooplankton associations) measured using the same sampling scheme in 2006 and 2009 to assess whether the same groups show the same environmental association year after year. This reveals complex dynamics with populations falling primarily into two categories: (i) nearly equally represented in each of the two samplings and (ii) highly skewed, often to an extent that they appear exclusive to one or the other sampling times. Importantly, populations recovered at the same abundance in both samplings occupied highly similar habitats suggesting predictable and robust environmental association while skewed abundances of some populations may be triggered by shifts in ecological conditions. The latter is supported by difference in the composition of large eukaryotic plankton between years, with samples in 2006 being dominated by copepods, and those in 2009 by diatoms. Overall, the comparison supports highly predictable population-habitat linkage but highlights the fact that complex, and often unmeasured, environmental dynamics in habitat occurrence may have strong effects on population dynamics. PMID:23178668

Szabo, Gitta; Preheim, Sarah P; Kauffman, Kathryn M; David, Lawrence A; Shapiro, Jesse; Alm, Eric J; Polz, Martin F

2013-01-01

406

Highly toxic Microcystis aeruginosa strain, isolated from São Paulo-Brazil, produce hepatotoxins and paralytic shellfish poison neurotoxins.  

PubMed

While evaluating several laboratory-cultured cyanobacteria strains for the presence of paralytic shellfish poison neurotoxins, the hydrophilic extract of Microcystis aeruginosa strain SPC777--isolated from Billings's reservoir, São Paulo, Brazil--was found to exhibit lethal neurotoxic effect in mouse bioassay. The in vivo test showed symptoms that unambiguously were those produced by PSP. In order to identify the presence of neurotoxins, cells were lyophilized, and the extracts were analyzed by HPLC-FLD and HPLC-MS. HPLC-FLD analysis revealed four main Gonyautoxins: GTX4(47.6%), GTX2(29.5%), GTX1(21.9%), and GTX3(1.0%). HPLC-MS analysis, on other hand, confirmed both epimers, with positive Zwitterions M(+) 395.9 m/z for GTX3/GTX2 and M(+) 411 m/z for GTX4/GTX1 epimers.The hepatotoxins (Microcystins) were also evaluated by ELISA and HPLC-MS analyses. Positive immunoreaction was observed by ELISA assay. Alongside, the HPLC-MS analyses revealed the presence of [L: -ser(7)] MCYST-RR. The N-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA was chosen as the target sequence to detect the presence of the mcy gene cluster. PCR amplification of the NMT domain, using the genomic DNA of the SPC777 strain and the MSF/MSR primer set, resulted in the expected 1,369 bp product. The phylogenetic analyses grouped the NMT sequence with the NMT sequences of other known Microcystis with high bootstrap support. The taxonomical position of M. aeruginosa SPC777 was confirmed by a detailed morphological description and a phylogenetic analysis of 16S rRNA gene sequence. Therefore, co-production of PSP neurotoxins and microcystins by an isolated M. aeruginosa strain is hereby reported for the first time. PMID:20376712

Sant'Anna, Célia L; de Carvalho, Luciana R; Fiore, Marli F; Silva-Stenico, Maria Estela; Lorenzi, Adriana S; Rios, Fernanda R; Konno, Katsuhiro; Garcia, Carlos; Lagos, Nestor

2011-04-01

407

Towards Reproducible Descriptions of Neuronal Network Models  

PubMed Central

Progress in science depends on the effective exchange of ideas among scientists. New ideas can be assessed and criticized in a meaningful manner only if they are formulated precisely. This applies to simulation studies as well as to experiments and theories. But after more than 50 years of neuronal network simulations, we still lack a clear and common understanding of the role of computational models in neuroscience as well as established practices for describing network models in publications. This hinders the critical evaluation of network models as well as their re-use. We analyze here 14 research papers proposing neuronal network models of different complexity and find widely varying approaches to model descriptions, with regard to both the means of description and the ordering and placement of material. We further observe great variation in the graphical representation of networks and the notation used in equations. Based on our observations, we propose a good model description practice, composed of guidelines for the organization of publications, a checklist for model descriptions, templates for tables presenting model structure, and guidelines for diagrams of networks. The main purpose of this good practice is to trigger a debate about the communication of neuronal network models in a manner comprehensible to humans, as opposed to machine-readable model description languages. We believe that the good model description practice proposed here, together with a number of other recent initiatives on data-, model-, and software-sharing, may lead to a deeper and more fruitful exchange of ideas among computational neuroscientists in years to come. We further hope that work on standardized ways of describing—and thinking about—complex neuronal networks will lead the scientific community to a clearer understanding of high-level concepts in network dynamics, and will thus lead to deeper insights into the function of the brain. PMID:19662159

Nordlie, Eilen; Gewaltig, Marc-Oliver; Plesser, Hans Ekkehard

2009-01-01

408

Supernova dynamics in the laboratory: Radiative shocks produced by ultra-high pressure implosion experiments on the National Ignition Facility  

NASA Astrophysics Data System (ADS)

Thermonuclear fuel experiments on the National Ignition Facility implode 2-mm diameter capsules with a cryogenic deuterium-tritium ice layer to 1000x liquid density and pressures exceeding 100 Gbar (10^11 atm). About 200 ps after peak compression, a spherical supernova-like radiative shock wave is observed that expands with shock velocities of uS = 300 km/s, temperatures of order 1 keV at densities of 1 g/cc resulting in a radiation strength parameter of Q ˜uS^5 = 10^4. Radiation-hydrodynamic simulations indicate that the shock launched at stagnation first goes down a strong density gradient while propagating outward from the highly compressed DT fuel (˜ 1000g/cc) to the ablation front (˜ 1 g/cc). Similar to what happens inside a star, the shock pressure drops as it accelerates and heats. The radiative shock emission is first observed when it breaks out of the dense compressed fuel shell into the low-density inflowing plasma at the ablation front mimicking the supernova situation where the shock breaks out through the star surface into surrounding in-falling matter [1,2]; the shock is subsequently approaching the supercritical state with a strong pre-cursor followed by rapid cooling. These observations are consistent with the rapid vanishing of the radiation ring 400 ps after peak compression due to strong radiation losses and spherical expansion. The evolution and brightness of the radiative shock provides insight into the performance of these implosions that have the goal to produce burning fusion plasmas in the laboratory. By modifying the capsule ablator composition and thickness, the stagnation pressure, density gradients, shock velocity and radiative properties could be tailored to study various regimes related to supernovae radiative remnants.[4pt] [1] W. David Arnett, Supernovae as phenomena of high-energy astrophysics, Ann NY Aca. Science 302, 90 (1977).[0pt] [2] L. Ensman and A. Burrows, Shock breakout in SN1987A, ApJ 393, 742.

Pak, Arthur

2012-10-01

409

Anisotropy of energy losses in high-current Z-pinches produced by the implosion of cylindrical tungsten wire arrays  

NASA Astrophysics Data System (ADS)

Results are presented from measurements of the anisotropy of energy losses in high-current Z-pinches produced by the implosion of wire arrays at the ANGARA-5-1 facility at load currents of up to 4MA. The energy losses were measured in the radial direction and along the pinch axis from the anode side. The main diagnostics were time-integrated thermocouple calorimeters, nanosecond X-ray diodes (XRDs) with different filters, and a foil radiation calorimeter with a time resolution of 2 ?s. The azimuthal anisotropy of energy losses was measured for different wire array configurations and different shapes of the high-voltage electrode. The presence of strong initial azimuthal inhomogeneity of the wire mass distribution (sectioned arrays), as well as the use of conical electrodes instead of plane ones, does not increase the azimuthal inhomogeneity of the total energy losses. For cylindrical wire arrays, energy losses in the radial direction are compared with those along the pinch axis. According to XRD and calorimetric measurements, the radiation yield per unit solid angle along the pinch axis is two to three times lower than that in the radial direction. In the axial direction, the energy flux density of the expanding plasma is two to three times lower than the radiation intensity. The measured radiation yield across the pinch is 2.5-5 kJ/sr, while that along the pinch axis is 1-2 kJ/sr. The results obtained by means of XRDs agree to within measurement errors with those obtained using the radiation calorimeter. It is found that the energy per unit solid angle carried by the expanding plasma in the radial direction does not exceed 10% of the soft X-ray yield. Analysis of the structure of time-integrated pinhole images and signals from the radial and axial XRDs shows that radiation emitted in the radial direction from the hot central region of the pinch is partially screened by the less dense surrounding plasma halo, whereas radiation emitted in the axial direction is a superposition of the emissions from the hot dense central region of the pinch and the colder less dense peripheral plasma.

Aleksandrov, V. V.; Volkov, G. S.; Grabovski, E. V.; Gritsuk, A. N.; Lakhtyushko, N. I.; Medovshchikov, S. F.; Oleinik, G. M.; Svetlov, E. V.

2014-02-01

410

High-throughput pyrosequencing of the chloroplast genome of a highly neutral-lipid-producing marine pennate diatom, Fistulifera sp. strain JPCC DA0580.  

PubMed

The chloroplast genome of the highly neutral-lipid-producing marine pennate diatom Fistulifera sp. strain JPCC DA0580 was fully sequenced using high-throughput pyrosequencing. The general features and gene content were compared with three other complete diatom chloroplast genomes. The chloroplast genome is 134,918 bp with an inverted repeat of 13,330 bp and is slightly larger than the other diatom chloroplast genomes due to several low gene-density regions lacking similarity to the other diatom chloroplast genomes. Protein-coding genes were nearly identical to those from Phaeodactylum tricornutum. On the other hand, we found unique sequence variations in genes of photosystem II which differ from the consensus in other diatom chloroplasts. Furthermore, five functional unknown ORFs and a putative serine recombinase gene, serC2, are located in the low gene-density regions. SerC2 was also identified in the plasmids of another pennate diatom, Cylindrotheca fusiformis, and in the plastid genome of the diatom endosymbiont of Kryptoperidinium foliaceum. Exogenous plasmids might have been incorporated into the chloroplast genome of Fistulifera sp. by lateral gene transfer. Chloroplast genome sequencing analysis of this novel diatom provides many important insights into diatom evolution. PMID:21290260

Tanaka, Tsuyoshi; Fukuda, Yorikane; Yoshino, Tomoko; Maeda, Yoshiaki; Muto, Masaki; Matsumoto, Mitsufumi; Mayama, Shigeki; Matsunaga, Tadashi

2011-09-01

411

Reproducibility of a silicone-based test food to masticatory performance evaluation by different sieve methods.  

PubMed

The aim of this study was to evaluate the reproducibility of the condensation silicone Optosil Comfort® as an artificial test food for masticatory performance evaluation. Twenty dentate subjects with mean age of 23.3±0.7 years were selected. Masticatory performance was evaluated using the simple (MPI), the double (IME) and the multiple sieve methods. Trials were carried out five times by three examiners: three times by the first, and once by the second and third examiners. Friedman's test was used to find the differences among time trials. Reproducibility was determined by the intra-class correlation (ICC) test (?=0.05). No differences among time trials were found, except for MPI-4 mm (p=0.022) from the first examiner results. The intra-examiner reproducibility (ICC) of almost all data was high (ICC?0.92, p<0.001), being moderate only for MPI-0.50 mm (ICC=0.89, p<0.001). The inter-examiner reproducibility was high (ICC>0.93, p<0.001) for all results. For the multiple sieve method, the average mean of absolute difference from repeated measurements were lower than 1 mm. This trend was observed only from MPI-0.50 to MPI-1.4 for the single sieve method, and from IME-0.71/0.50 to IME-1.40/1.00 for the double sieve method. The results suggest that regardless of the method used, the reproducibility of Optosil Comfort® is high. PMID:24918363

Sánchez-Ayala, Alfonso; Vilanova, Larissa Soares Reis; Costa, Marina Abrantes; Farias-Neto, Arcelino

2014-01-01

412

A measurement of the polarization of J\\/Psi mesons produced in high-energy proton-antiproton collisions  

Microsoft Academic Search

This dissertation presents an analysis of the polarization of J\\/ y mesons produced in pp¯ collisions at a centre-of-mass energy of 1.8 TeV. The collisions were produced by the Fermilab Tevatron collider, the world's highest energy particle accelerator. The data were recorded by the Collider Detector at Fermilab during Run 1 of the Tevatron in 1992-1995. The J\\/ y meson

Robert James Cropp

2000-01-01

413

Repeatability and Reproducibility of Fibre-Based Nanogenerator Synthesized by Electrospinning Machine  

NASA Astrophysics Data System (ADS)

Zinc oxide fibres-based nanogenerators synthesized easily by electrospinning machine are promising to harvest electricity from mechanical energy. However, the repeatability and reproducibility were two major factors needed to be investigated to minimize product failure and to determine the feasibility of mass production of nanogenerators. The green fibres of zinc oxide were produced by electrospinning machine of zinc acetate and polyvinyl alcohol solution at a flow rate of 4 ?L/min followed by sintering at temperature 550°C with heating rate 240°C/h. Each 10 nanogenerators was tested by three trained operators with three times of repetition at compressive load 0.5 kg. The nanogenerators revealed the maximum output voltage ranging from 203 to 217 mV. The value of repeatability and reproducibility of nanogenerators was approximately 24.29% showing that nanogenerators were still acceptable to be mass-produced. The relatively low reproducibility was mainly due to the operators, so that the checklist needed to be made easier and simpler for all the variables affecting to the quality of the fibres. Reducing the value of the repeatability and reproducibility is interesting to study further by creating a rotating collector so that the thickness and orientation of fibres can be arranged better.

Suyitno; Huda, Sholiehul; Arifin, Zainal; Hadi, Syamsul; Lullus Lambang, Raymundus

2014-06-01

414

High-resolution measurement of the He-[beta] spectra of heliumlike chromium for possible diagnostic of laser-produced plasmas  

SciTech Connect

High-resolution He-[beta] spectra of heliumlike chromium have been recorded in an effort to provide accurate atomic data useful for the development of diagnostics of the electron temperature and density for laser-produced plasmas. The He-[beta] spectra are of particular interest for these very-high-density plasmas ([ital n][sub [ital e

Decaux, V.; Beiersdorfer, P.; Elliott, S.; Osterheld, A. (Lawrence Livermore National Laboratory, University of California, Livermore, California 94551 (United States)); Clothiaux, E. (Department of Physics, Auburn University, Auburn, Alabama 36849 (United States))

1995-01-01

415

Effects of twinning on the subsequent reproductive performance and productive lifespan of high-producing dairy cows.  

PubMed

This study was designed to determine the effects of twinning on the subsequent reproductive performance and productive lifespan of high milk-producing dairy cows. The data analyzed were taken from complete reproductive records for 4861 Holstein Friesian cows comprising a commercial herd, including data for 12 587 calving events from April 1, 2001 to March 31, 2012. The twinning rate was 5.6%, and 9.6% of the cows delivered twins at least once during their life. Conception rates before Days 90, 120, and 300 postpartum were 20.8%, 36.9%, and 74.5%, and 34.2%, 51.8%, and 85.0% for cows delivering twins and singletons, respectively. Cox regression analysis revealed that twinning reduced the chances of conception before Day 90 by a factor of 0.76. Also, the median calving to conception interval was significantly longer for cows calving twins (134 ± 4.5 days) than for cows delivering singletons (108 ± 0.8 days; P < 0.001). Moreover, in cows in which conception was successful, the risk of abortion was higher for cows that calved twins than for those calving singletons (13.7% vs. 10.3%, respectively; P = 0.01). Culling rates before Days 90, 120, and 300 postpartum were 15.6%, 16.1%, and 28.6%, and 7.6%, 8.7%, and 15.9% for cows calving twins and singletons, respectively. Cox regression analysis of the factors affecting the culling rate before Day 300 postpartum revealed a 1.41 times greater hazard ratio of culling for cows calving twins than cows calving singletons. Further, mean productive lifespan was almost 300 days shorter for primiparous twinners (N = 48, 602 ± 493 days) than for nontwinners (N = 2592; 899 ± 581 days; P < 0.01), and 200 days shorter for secundiparous twinners (N = 126, 914 ± 429 days) than for nontwinners undergoing at least two lactations (N = 1936, 1101 ± 522 days; P < 0.01). Kaplan-Meier survival curves for productive lifespan differed between primiparous twinners and non-twinners (P < 0.001), and between secundiparous twinners and nontwinners having at least two lactations (P = 0.017). Differences in culling patterns for twinners and nontwinners were not restricted to the subsequent lactation but continued as long as 800 days after first calving, strongly suggesting long-term negative effects of twinning. As an economic implication of our findings, we suggest that twin embryo reduction at the moment of pregnancy diagnosis could be a profitable strategy to cut twinning rates and abolish their detrimental effects on subsequent reproductive performance and productive lifespan. PMID:23043948

Andreu-Vázquez, C; Garcia-Ispierto, I; Ganau, S; Fricke, P M; López-Gatius, F

2012-12-01

416