WorldWideScience

Sample records for concentration improves cryotolerance

  1. Elevated NaCl concentration improves cryotolerance and developmental competence of porcine oocytes

    DEFF Research Database (Denmark)

    Lin, L; Du, Y; Liu, Y

    2009-01-01

    High hydrostatic pressure has been reported to improve the fertilizing or developmental ability of mammalian spermatozoa, oocytes and embryos. This study investigated the effect of another stress, temporarily increased NaCl concentration, on cryotolerance and developmental competence of porcine...

  2. The improving effect of reduced glutathione on boar sperm cryotolerance is related with the intrinsic ejaculate freezability.

    Science.gov (United States)

    Yeste, Marc; Estrada, Efrén; Pinart, Elisabeth; Bonet, Sergi; Miró, Jordi; Rodríguez-Gil, Joan E

    2014-04-01

    Reduced glutathione (GSH) improves boar sperm cryosurvival and fertilising ability when added to freezing extenders. Poor freezability ejaculates (PFE) are known to present lower resistance than good freezability ejaculates (GFE) to cryopreservation procedures. So far, no study has evaluated whether the ability of GSH to counteract the cryopreservation-induced injuries depends on ejaculate freezability (i.e. GFE vs. PFE). For this reason, thirty boar ejaculates were divided into three equal volume fractions and cryopreserved with or without GSH at a final concentration of either 2 or 5mM in freezing media. Before and after freeze-thawing, sperm quality was evaluated through analysis of viability, motility, integrity of outer acrosome membrane, ROS levels, integrity of nucleoprotein structure, and DNA fragmentation. Ejaculates were classified into two groups (GFE or PFE) according to their post-thaw sperm motility and viability assessments in negative control (GSH 0mM), after running cluster analyses. Values of each sperm parameter were then compared between treatments (GSH 0mM, GSH 2mM, GSH 5mM) and freezability groups (GFE, PFE). In the case of GFE, GSH significantly improved boar sperm cryotolerance, without differences between 2 and 5mM. In contrast, PFE freezability was significantly increased when supplemented with 5mM GSH, but not when supplemented with 2mM GSH. In conclusion, PFE need a higher concentration of GSH than GFE to improve their cryotolerance. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Osmotic stress induced by sodium chloride, sucrose or trehalose improves cryotolerance and developmental competence of porcine oocytes

    DEFF Research Database (Denmark)

    Lin, Lin; Kragh, Peter Michael; Purup, Stig

    2009-01-01

    Cl with those of concentrated solutions of two non-permeable osmotic agents, namely sucrose and trehalose, on the cryotolerance and developmental competence of porcine oocytes. In Experiment 1, porcine in vitro-matured cumulus-oocyte complexes (COCs; n = 1200) were exposed to 588 mOsmol NaCl, sucrose...... or trehalose solutions for 1 h, allowed to recover for a further 1 h, vitrified, warmed and subjected to parthenogenetic activation. Both Day 2 (where Day 0 is the day of activation) cleavage and Day 7 blastocyst rates were significantly increased after NaCl, sucrose and trehalose osmotic treatments compared...... with untreated controls (cleavage: 46 ± 5%, 44 ± 7%, 45 ± 4% and 26 ± 6%, respectively; expanded blastocyst rate: 6 ± 1%, 6 ± 2%, 7 ± 2% and 1 ± 1%, respectively). In Experiment 2, COCs (n = 2000) were treated with 588 mOsmol NaCl, sucrose or trehalose, then used as recipients for SCNT (Day 0). Cleavage rates...

  4. Microfiltration conditions modify Lactobacillus bulgaricus cryotolerance in response to physiological changes.

    Science.gov (United States)

    Streit, Fernanda; Athès, Violaine; Bchir, Amine; Corrieu, Georges; Béal, Catherine

    2011-02-01

    This work aimed at analyzing the effect of microfiltration conditions (cross-flow velocity and transmembrane pressure) on the quality of frozen Lactobacillus bulgaricus CFL1 starters produced on pilot scale. Microfiltered cells were less resistant during the concentration process than centrifuged cells. In contrast, bacterial cryotolerance during freezing was improved after microfiltration, in a range of 28-88%, depending on the microfiltration conditions. During frozen storage, cell resistance was also affected by microfiltration conditions, either positively or negatively, compared to centrifugation. The best cryotolerance was obtained for cells microfiltered at a cross-flow velocity of 2 m/s and a transmembrane pressure of 0.15 MPa. This improvement was explained by considering membrane fatty acid composition of Lb. bulgaricus CFL1. This condition increased unsaturated to saturated and cyclic to saturated fatty acid ratios, which enhanced membrane fluidity, thus helping the cells to better resist freezing and frozen storage.

  5. Cysteamine supplementation during in vitro maturation of slaughterhouse- and opu-derived bovine oocytes improves embryonic development without affecting cryotolerance, pregnancy rate, and calf characteristics.

    Science.gov (United States)

    Merton, J S; Knijn, H M; Flapper, H; Dotinga, F; Roelen, B A J; Vos, P L A M; Mullaart, E

    2013-09-01

    Optimization of ovum pick up (OPU) followed by in vitro embryo production (IVP) is strongly driven by the needs of both beef and dairy cattle breeders to enhance genetic improvement. The rapidly growing use of genomic selection in cattle has increased the interest in using OPU-IVP technology to increase the number of embryos and offspring per donor, thus allowing enhanced selection intensity for the next generation. The aim of this study was to optimize embryo production through supplementation of cysteamine during in vitro maturation (IVM) and in vitro culture (IVC) of both slaughterhouse- and OPU-derived oocytes. The effects on embryo production and on embryo cryotolerance, post-transfer embryo survival, and calf characteristics, including gestation length, birth weight, perinatal mortality, and sex ratio were studied. In study 1, immature slaughterhouse-derived cumulus-oocyte complexes (COCs) were matured in IVM medium supplemented with or without 0.1 mM cysteamine, fertilized and cultured for 7 days in 0.5 ml SOFaaBSA. In study 2, cysteamine was present during both IVM (0.1 mM) and IVC (0.01, 0.05, 0.1 mM) from Days 1 to 4. In study 3, OPU-derived COCs were matured in medium supplemented with or without 0.1 mM cysteamine in a 2 × 2 factorial design (OPU week and cysteamine treatment). Embryos were evaluated for stage and grade on Day 7 and, depending on the number of transferable embryos and recipients available, the embryos were transferred either fresh or frozen-thawed at a later date. The presence of cysteamine during IVM significantly increased the embryo production rate with slaughterhouse-derived COCs (24.0% vs. 19.4%). The higher number of embryos at Day 7 was due to an increased number of blastocysts, whereas the distribution of embryos among different quality grades and cryotolerance was not affected. Embryo production rate was negatively affected when cysteamine was present during both the processes of IVM and IVC during Days 1 to 4 of culture (13

  6. Melatonin improves the quality of in vitro produced (IVP bovine embryos: implications for blastocyst development, cryotolerance, and modifications of relevant gene expression.

    Directory of Open Access Journals (Sweden)

    Feng Wang

    Full Text Available To evaluate the potential effects of melatonin on the kinetics of embryo development and quality of blastocyst during the process of in vitro bovine embryo culture. Bovine cumulus-oocyte complexes (COCs were fertilized after in vitro maturation. The presumed zygotes were cultured in in vitro culture medium supplemented with or without 10(-7 M melatonin. The cleavage rate, 8-cell rate and blastocyst rate were examined to identify the kinetics of embryo development. The hatched blastocyst rate, mortality rate after thawing and the relevant transcript abundance were measured to evaluate the quality of blastocyst. The results showed that melatonin significantly promoted the cleavage rate and 8-cell embryo yield of in vitro produced bovine embryo. In addition, significantly more blastocysts were observed by Day 7 of embryo culture at the presence of melatonin. These results indicated that melatonin accelerated the development of in vitro produced bovine embryos. Following vitrification at Day 7 of embryo culture, melatonin (10(-7 M significantly increased the hatched blastocyst rate from 24 h to 72 h and decreased the mortality rate from 48 h to 72 h after thawing. The presence of melatonin during the embryo culture resulted in a significant increase in the gene expressions of DNMT3A, OCC, CDH1 and decrease in that of AQP3 after thawing. In conclusion, melatonin not only promoted blastocyst yield and accelerated in vitro bovine embryo development, but also improved the quality of blastocysts which was indexed by an elevated cryotolerance and the up-regulated expressions of developmentally important genes.

  7. Vitamin K2 improves developmental competency and cryo-tolerance of in vitro derived ovine blastocyst.

    Science.gov (United States)

    Sefid, Fatemeh; Ostadhosseini, S; Hosseini, S M; Ghazvini Zadegan, F; Pezhman, M; Nasr Esfahani, Mohammad Hossein

    2017-08-01

    Vitamin K2 (VK2), acts as an electron carrier in mitochondria and thereby effects reactive oxygen species (ROS) and ATP production. This study evaluates role of VK2 on in vitro developmental competency and cryo-survival of pre-implantation ovine embryos. Initially the optimal and beneficial concentration of VK2 on compaction and blastocyst formation rates was defined (0.1 μM). Subsequently, it was shown that 0.1 μM VK2, at blastocyst stage, reduces H2O2 production, increase the expression of mitochondrial related gene and improved embryos quality. We further assessed presence VK2 supplementation before and/or after vitrification of in vitro derived blastocysts. Our results reveal that presence of VK2 before and after vitrification improves rates of blastocysts re-expansion (88.19± 3.37% vs 73.68± 1.86%, P < 0.05) and hatching (49.55± 4.37% vs 32.7± 3.32%) compared to control group. These observation were consistent with reduction in H2O2 production and improved in expression of mitochondrial related genes. However, VK2 before or after vitrification, not only had no positive effect on these two parameters, but also significantly reduced these parameters. Therefore, in concordance with pervious report in bovine, we show that VK2 supplementation post genomic activation (Day 3-7) improved developmental competency of ovine in vitro derived embryos. We also showed that presence of VK2 after vitrification improves the cryo-survival of ovine embryos. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Lipid content and cryotolerance of in vitro-produced bovine embryos treated with forskolin before vitrification

    Directory of Open Access Journals (Sweden)

    Melissa Meneghel

    Full Text Available ABSTRACT: The aim of the present study was to evaluate the intracytoplasmic lipid content, development and cryotolerance of in vitro-produced bovine embryos treated with different concentrations of forskolin before vitrification. Embryos were produced from abattoir-derived ovaries and allocated into four groups. In the treatment groups, forskolin was added to the in vitro culture medium on Day 6 and incubated for 24 hours in one of the following concentrations: 2.5μM (Forsk 2.5 group, 5.0μM (Forsk 5.0 group or 10.0μM (Forsk 10.0 group. Embryos from the control group were cultured without forskolin. On Day 7 of culture, the expanded blastocysts were stained with the lipophilic dye Sudan Black B for determination of the intracytoplasmic lipid content or were cryopreserved via the Vitri-Ingá® procedure. Although there were no significant differences (P>0.05 in the blastocyst rates between the Control group (44.9% and the other treatments, the embryo production was lower (P0.05 to that found in Forsk 2.5 (0.92±0.03 and Forsk 10.0 groups (1.06±0.03 groups; however the lipid accumulation in blastocysts from Forsk 5.0 group (0.82±0.04 was lower than in the Control group (P<0.05. Based on these results, Forsk 5.0 treatment was tested for cryotolerance and it was observed that the blastocoel re-expansion rate evaluated 24 hours after warming was greater (P<0.05 in Forsk 5.0 group (72.2% compared to the Control group (46.2%. In conclusion, pre-treatment with forskolin at a concentration of 5.0 μM for 24 hours before vitrification is effective in reducing the intracytoplasmic lipid content and, consequently, improves cryotolerance of IVP bovine embryos.

  9. iTRAQ-based proteome profiling of Saccharomyces cerevisiae and cryotolerant species Saccharomyces uvarum and Saccharomyces kudriavzevii during low-temperature wine fermentation.

    Science.gov (United States)

    García-Ríos, Estéfani; Querol, Amparo; Guillamón, José Manuel

    2016-09-02

    Temperature is one of the most important parameters to affect the duration and rate of alcoholic fermentation and final wine quality. Some species of the Saccharomyces genus have shown better adaptation at low temperature than Saccharomyces cerevisiae, which was the case of cryotolerant yeasts Saccharomyces uvarum and Saccharomyces kudriavzevii. In an attempt to detect inter-specific metabolic differences, we characterized the proteomic landscape of these cryotolerant species grown at 12°C and 28°C, which we compared with the proteome of S. cerevisiae (poorly adapted at low temperature). Our results showed that the main differences among the proteomic profiling of the three Saccharomyces strains grown at 12°C and 28°C lay in translation, glycolysis and amino acid metabolism. Our data corroborate previous transcriptomic results, which suggest that S. kudriavzevii is better adapted to grow at low temperature as a result of enhanced more efficient translation. Fitter amino acid biosynthetic pathways can also be mechanisms that better explain biomass yield in cryotolerant strains. Yet even at low temperature, S. cerevisiae is the most fermentative competitive species. A higher concentration of glycolytic and alcoholic fermentation enzymes in the S. cerevisiae strain might explain such greater fermentation activity. Temperature is one of the main relevant environmental variables that microorganisms have to cope with and it is also a key factor in some industrial processes that involve microorganisms. However, we are still far from understanding the molecular and physiological mechanisms of adaptation at low temperatures. The results obtained in this study provided a global atlas of the proteome changes triggered by temperature in three different species of the genus Saccharomyces with different degree of cryotolerance. These results would facilitate a better understanding of mechanisms for how yeast could adapt at the low temperature of growth. Copyright © 2016

  10. Effect of the cryopreservation method used, the embryonic stage and the use of conjugated linoleic acid isomers on the cryotolerance of in vitro-produced bovine embryos

    Directory of Open Access Journals (Sweden)

    Luciana Simões Rafagnin Marinho

    2015-12-01

    Full Text Available Conjugated linoleic acid (CLA might be able to improve the cryotolerance of in vitro-produced (IVP embryos. The effect of two CLA isomers on the cryotolerance of bovine IVP embryos, as well as that of the stage of embryonic development and the method used for cryopreservation was evaluated by three experiments. In Experiment 1, oocytes (n = 3,917 were fertilized in vitro and cultured with 0, 50, 100, or 200 ?M trans-10, cis-12 (t10, c12 CLA. In Experiment 2, fertilized oocytes (n = 2,131 were cultured with 100 ?M t10, c12 or cis-9, trans-11 (c9, t11 CLA, or a combination of both isomers. The embryos were vitrified at the blastocyst (BL or the expanded blastocyst (EB stage. In Experiment 3, oocytes (n = 1,720 were fertilized and cultured with or without 100 ?M t10, c12 CLA, and the blastocysts were vitrified or frozen. Blastocyst development rate as well as the rates of re-expansion and hatching after thawing was recorded. Moreover, the mean cell number and mRNA expression of acetyl-CoA carboxylase (ACC1 and stearoyl-CoA desaturase (SCD1 as well as fatty acid synthase (FASN multienzyme complex were determined. In Experiment 1, the highest concentration of t10, c12 CLA that did not reduce blastocyst development rate was 100 ?M. In Experiment 2, the rates of re-expansion and hatching among the EBs obtained through IVP after supplementation with t10, c12 CLA (73.1% and 57.7%, with c9, t11 CLA (80.0% and 68.6%, with the combination (78.3% and 52.2%, and with the control group (85.4% and 58.3% were similar. At the BL stage, the rates of re-expansion and hatching were lower than those at the EB stage, and CLA combination allowed a hatching rate (8.0% lower than that observed in the control group (40.0%. In Experiment 3, the hatching rates for vitrified EBs (vitrified control; 67.4% and vitrified CLA EBs (65.8% were higher than those obtained for frozen EBs, exposed (13.3% or not exposed (28.6% to CLA. In addition, in Experiment 3, the hatching rate was

  11. Improved ATIR concentrator photovoltaic module

    Science.gov (United States)

    Adriani, Paul M.; Mao, Erwang

    2013-09-01

    Novel aggregated total internal reflection (ATIR) concentrator photovoltaic module design comprises 2-D shaped primary and secondary optics that effectively combine optical efficiency, low profile, convenient range of acceptance angles, reliability, and manufacturability. This novel optical design builds upon previous investigations by improving the shapes of primary and secondary optics to enable improved long-term reliability and manufacturability. This low profile, low concentration (5x to 10x) design fits well with one-axis trackers that are often used for flat plate crystalline silicon photovoltaic modules in large scale ground mount installations. Standard mounting points, materials, and procedures apply without changes from flat plate modules.

  12. Photovoltaic concentrator module improvements study

    Energy Technology Data Exchange (ETDEWEB)

    Levy, S.L.; Kerschen, K.A. (Black and Veatch, Kansas City, MO (United States)); Hutchison, G. (Solar Kinetics, Inc., Dallas, TX (United States)); Nowlan, M.J. (Spire Corp., Bedford, MA (United States))

    1991-08-01

    This report presents results of a project to design and fabricate an improved photovoltaic concentrator module. Using previous work as a baseline, this study conducted analyses and testing to select major module components and design features. The lens parquet and concentrator solar cell were selected from the highest performing, available components. A single 185X point-focus module was fabricated by the project team and tested at Sandia. Major module characteristics include a 6 by 4 compression-molded acrylic lens parquet (0.737 m{sup 2} area), twenty-four 0.2 ohms-cm, FZ, p-Si solar cells (1.56 cm{sup 2} area) soldered to ceramic substrates and copper heat spreaders, and an aluminized steel housing with corrugated bottom. This project marked the first attempt to use prismatic covers on solar cells in a high-concentration, point-focus application. Cells with 15 percent metallization were obtained, but problems with the fabrication and placement of prismatic covers on these cells lead to the decision not to use covers in the prototype module. Cell assembly fabrication, module fabrication, and module optical design activities are presented here. Test results are also presented for bare cells, cell assemblies, and module. At operating conditions of 981 watts/m{sup 2} DNI and an estimated cell temperature of 65{degrees}C, the module demonstrated an efficiency of 13.9 percent prior to stressed environmental exposure. 12 refs., 56 figs., 7 tabs.

  13. Improved cider fermentation performance and quality with newly generated Saccharomyces cerevisiae × Saccharomyces eubayanus hybrids.

    Science.gov (United States)

    Magalhães, Frederico; Krogerus, Kristoffer; Vidgren, Virve; Sandell, Mari; Gibson, Brian

    2017-08-01

    Yeast cryotolerance may be advantageous for cider making, where low temperatures are usually employed. Here, we crossed the cryotolerant S. eubayanus with a S. cerevisiae wine strain and assessed the suitability of the hybrids for low-temperature cider fermentation. All strains fermented the juice to 5% ABV, but at different rates; hybrid strains outperformed S. cerevisiae, which was sensitive to low temperatures. The best hybrid fermented similarly to S. eubayanus. S. eubayanus produced sulphurous off flavours which masked a high concentration of fruity ester notes. This phenotype was absent in the hybrid strains, resulting in distinctly fruitier ciders. Aroma was assessed by an independent consumer panel, which rated the hybrid ciders as identical to the wine strain cider. Both were significantly more pleasant than the S. eubayanus cider. Interspecific hybridization can apparently be used effectively to improve low-temperature fermentation performance without compromising product quality.

  14. Combining reduced glutathione and ascorbic acid has supplementary beneficial effects on boar sperm cryotolerance.

    Science.gov (United States)

    Giaretta, Elisa; Estrada, Efrén; Bucci, Diego; Spinaci, Marcella; Rodríguez-Gil, Joan E; Yeste, Marc

    2015-02-01

    The main aim of this work was to evaluate how supplementing freezing and thawing media with reduced glutathione (GSH) and l-ascorbic acid (AA) affected the quality parameters of frozen-thawed boar spermatozoa. With this purpose, semen samples of 12 ejaculates coming from 12 boars were used. Each ejaculate was split into seven aliquots to which 5 mM of GSH and 100 μM of AA were added separately or together at two different steps of freeze-thawing. Various sperm parameters (levels of free cysteine residues in sperm nucleoproteins, sperm viability, acrosome membrane integrity, intracellular peroxide and superoxide levels [ROS], and total and progressive motility) were evaluated before freezing and at 30 and 240 minutes after thawing. Both GSH and AA significantly improved boar sperm cryotolerance when they were separately added to freezing and thawing media. However, the highest improvement was recorded when both freezing and thawing media were supplemented with 5 mM of GSH plus 100 μM of AA. This improvement was observed in sperm viability and acrosome integrity, sperm motility, and nucleoprotein structure. Although ROS levels were not much increased by freeze-thawing procedures, the addition of GSH and AA to both freezing and thawing extenders significantly decreased intracellular peroxide levels and had no impact on superoxide levels. According to our results, we can conclude that supplementation of freezing and thawing media with both GSH and AA has a combined, beneficial effect on frozen-thawed boar sperm, which is greater than that obtained with the separate addition of either GSH or AA. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Metabolomic comparison of Saccharomyces cerevisiae and the cryotolerant species S. bayanus var. uvarum and S. kudriavzevii during wine fermentation at low temperature.

    Directory of Open Access Journals (Sweden)

    María López-Malo

    Full Text Available Temperature is one of the most important parameters affecting the length and rate of alcoholic fermentation and final wine quality. Wine produced at low temperature is often considered to have improved sensory qualities. However, there are certain drawbacks to low temperature fermentations such as reduced growth rate, long lag phase, and sluggish or stuck fermentations. To investigate the effects of temperature on commercial wine yeast, we compared its metabolome growing at 12 °C and 28 °C in a synthetic must. Some species of the Saccharomyces genus have shown better adaptation at low temperature than Saccharomyces cerevisiae. This is the case of the cryotolerant yeasts Saccharomyces bayanus var. uvarum and Saccharomyces kudriavzevii. In an attempt to detect inter-specific metabolic differences, we characterized the metabolome of these species growing at 12°C, which we compared with the metabolome of S. cerevisiae (not well adapted at low temperature at the same temperature. Our results show that the main differences between the metabolic profiling of S. cerevisiae growing at 12 °C and 28 °C were observed in lipid metabolism and redox homeostasis. Moreover, the global metabolic comparison among the three species revealed that the main differences between the two cryotolerant species and S. cerevisiae were in carbohydrate metabolism, mainly fructose metabolism. However, these two species have developed different strategies for cold resistance. S. bayanus var. uvarum presented elevated shikimate pathway activity, while S. kudriavzevii displayed increased NAD(+ synthesis.

  16. Improved optical design of nontracking concentrators

    Science.gov (United States)

    Kwan, B. M.; Bannerot, R. B.

    1984-08-01

    Optical designs based on a two reflections or less criterion have been developed for one and two-facet trapezoidal concentrators. Collector designs resulting from this criterion have been evaluated with the aid of a ray-trace computer simulation which includes the effects of nonideal reflectors. Results indicate a marked increase in performance, particularly for the one-facet designs, as compared to the collectors previously designed with the one reflection or less criterion. A significant result is that when a proper accounting is made for the actual acceptance angle for the concentrators, the performances of the optimal one and two-facet designs become nearly identical, indicating that the previously held contention that improved performance could be achieved with multifaceted reflectors (geometrically approaching the compound parabolic shape) may be incorrect.

  17. A low membrane lipid phase transition temperature is associated with a high cryotolerance of Lactobacillus delbrueckii subspecies bulgaricus CFL1.

    Science.gov (United States)

    Gautier, J; Passot, S; Pénicaud, C; Guillemin, H; Cenard, S; Lieben, P; Fonseca, F

    2013-09-01

    The mechanisms of cellular damage that lactic acid bacteria incur during freeze-thaw processes have not been elucidated to date. Fourier transform infrared spectroscopy was used to investigate in situ the lipid phase transition behavior of the membrane of Lactobacillus delbrueckii ssp. bulgaricus CFL1 cells during the freeze-thaw process. Our objective was to relate the lipid membrane behavior to membrane integrity losses during freezing and to cell-freezing resistance. Cells were produced by using 2 different culture media: de Man, Rogosa, and Sharpe (MRS) broth (complex medium) or mild whey-based medium (minimal medium commonly used in the dairy industry), to obtain different membrane lipid compositions corresponding to different recovery rates of cell viability and functionality after freezing. The lipid membrane behavior studied by Fourier transform infrared spectroscopy was found to be different according to the cell lipid composition and cryotolerance. Freeze-resistant cells, exhibiting a higher content of unsaturated and cyclic fatty acids, presented a lower lipid phase transition temperature (Ts) during freezing (Ts=-8°C), occurring within the same temperature range as the ice nucleation, than freeze-sensitive cells (Ts=+22°C). A subzero value of lipid phase transition allowed the maintenance of the cell membrane in a relatively fluid state during freezing, thus facilitating water flux from the cell and the concomitant volume reduction following ice formation in the extracellular medium. In addition, the lipid phase transition of freeze-resistant cells occurred within a short temperature range, which could be ascribed to a reduced number of fatty acids, representing more than 80% of the total. This short lipid phase transition could be associated with a limited phenomenon of lateral phase separation and membrane permeabilization. This work highlights that membrane phase transitions occurring during freeze-thawing play a fundamental role in the

  18. Compact Flyeye concentrator with improved irradiance uniformity on solar cell

    Science.gov (United States)

    Zhuang, Zhenfeng; Yu, Feihong

    2013-08-01

    A Flyeye concentrator with improved irradiance distribution on the solar cell in a concentrator photovoltaic system is proposed. This Flyeye concentrator is composed of four surfaces: a refractive surface, mirror surface, freeform surface, and transmissive surface. Based on the principles of geometrical optics, the contours of the proposed Flyeye concentrator are calculated according to Fermat's principle, the edge-ray principle, and the ray reversibility principle without solving partial differential equations or using an optimization algorithm, therefore a slope angle control method is used to construct the freeform surface. The solid model is established by applying a symmetry of revolution around the optical axis. Additionally, the optical performance for the Flyeye concentrator is simulated and analyzed by Monte-Carlo method. Results show that the Flyeye concentrator optical efficiency of >96.2% is achievable with 1333× concentration ratio and ±1.3 deg acceptance angle, and 1.3 low aspect ratio (average thickness to entry aperture diameter ratio). Moreover, comparing the Flyeye concentrator specification to that of the Köhler concentrator and the traditional Fresnel-type concentrator, results indicate that this concentrator has the advantages of improved uniformity, reduced thickness, and increased tolerance to the incident sunlight.

  19. Cholesterol added prior to vitrification on the cryotolerance of immature and in vitro matured bovine oocytes.

    Directory of Open Access Journals (Sweden)

    Núria Arcarons

    Full Text Available This study examines whether incorporating cholesterol-loaded methyl-β-cyclodextrin (CLC in the bovine oocyte plasma membrane improves oocyte tolerance to vitrification. In vitro matured oocytes were incubated with 2 mg/ml BODIPY-labeled CLC for different time intervals in FCS or PVA supplemented medium or exposed to different CLC concentrations to examine the subcellular localization of cholesterol by confocal microscopy live-cell imaging. Subsequently, the effects of optimized CLC concentrations and incubation times prior to vitrification on early embryo development were assessed. Then, we evaluated the effects of pretreatment with 2 mg/ml CLC for 30 min before the vitrification of immature (GV and in vitro matured (MII oocytes on developmental competence and gene expression. Our results indicate a high plasma membrane labeling intensity after 30 min of incubation with 2 mg/ml CLC for 30 min, regardless of the holding medium used. When oocytes were incubated with 1 mg/ml, 2 mg/ml and 3 mg/ml of CLC, intense labeling was observed at the plasma membrane after 40, 30 and 20 min, respectively. CLC pre-treatment before the vitrification of bovine oocytes did not affect subsequent cleavage and embryo development rates irrespective of CLC concentrations, incubation times or meiotic stage. However, pretreatment seems to improve the quality of embryos derived from vitrified oocytes, mainly when oocytes were vitrified at the GV stage.

  20. Technology for improving sludge concentration; Odei noshukusei kaizen gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-10

    Sludge generating in a sewage treatment plant is disposed through the processes such as concentration, dehydration, and incineration in sludge disposal facilities. In recent years, there has been a trend that this sludge increases in volume as well as worsens in the concentration. A case is predictable where the sludge load to the dehydrating process is so large that the sludge can no longer be processed in sufficient quantity. In the meantime, if sludge is ozone-treated, viscous substance on the surface of sludge particles can be separated with a comparatively small amount of ozone, with sludge concentration enhanced. At Meidensha, an experimental plant was set up for the ozone treatment of sludge in a sludge intensive treatment plant of a metropolis, with a verification experiment carried out for a sludge concentration improving system by ozone. As a result of comparison of the treatment performance between an assessment system for performing ozone treatment and a reference system for not performing, the average value of the sludge concentration of a gravity concentration tank was 1.9% of the reference system against 1.7% of the assessment system in a continuous treatment experiment in the summer, while the solid collection ratio was 65.8% of the reference system against 95.5% of the assessment system, enabling a superior improving effect to be obtained. (NEDO)

  1. Toward improved analysis of concentration data: Embracing nondetects.

    Science.gov (United States)

    Shoari, Niloofar; Dubé, Jean-Sébastien

    2018-03-01

    Various statistical tests on concentration data serve to support decision-making regarding characterization and monitoring of contaminated media, assessing exposure to a chemical, and quantifying the associated risks. However, the routine statistical protocols cannot be directly applied because of challenges arising from nondetects or left-censored observations, which are concentration measurements below the detection limit of measuring instruments. Despite the existence of techniques based on survival analysis that can adjust for nondetects, these are seldom taken into account properly. A comprehensive review of the literature showed that managing policies regarding analysis of censored data do not always agree and that guidance from regulatory agencies may be outdated. Therefore, researchers and practitioners commonly resort to the most convenient way of tackling the censored data problem by substituting nondetects with arbitrary constants prior to data analysis, although this is generally regarded as a bias-prone approach. Hoping to improve the interpretation of concentration data, the present article aims to familiarize researchers in different disciplines with the significance of left-censored observations and provides theoretical and computational recommendations (under both frequentist and Bayesian frameworks) for adequate analysis of censored data. In particular, the present article synthesizes key findings from previous research with respect to 3 noteworthy aspects of inferential statistics: estimation of descriptive statistics, hypothesis testing, and regression analysis. Environ Toxicol Chem 2018;37:643-656. © 2017 SETAC. © 2017 SETAC.

  2. Improved Growth And Colchicine Concentration In Gloriosa Superba ...

    African Journals Online (AJOL)

    AM), fungi, Glomus mossae, Glomus fasciculatum, Gigaspora margarita and Gigaspora gilmorei either alone or supplemented with P-fertilizer, on colchicine concentration in Gloriosa superba were studied. The concentration of colchicine was ...

  3. Genetic diversity for grain Zn concentration in finger millet genotypes: Potential for improving human Zn nutrition

    Directory of Open Access Journals (Sweden)

    Ramegowda Yamunarani

    2016-06-01

    Full Text Available Nearly half of the world population suffers from micronutrient malnutrition, particularly Zn deficiency. It is important to understand genetic variation for uptake and translocation behaviors of Zn in relevant crop species to increase Zn concentration in edible parts. In the present study, genetic variation in grain Zn concentration of 319 finger millet genotypes was assessed. Large genetic variation was found among the genotypes, with concentrations ranging from 10 to 86 μg g− 1 grain. Uptake and translocation studies with Zn/65Zn application in 12 selected low-Zn genotypes showed wide variation in root uptake and shoot translocation, with genotypes GEC331 and GEC164 showing greater uptake and translocation. Genotypes GEC164 and GEC543 showed increased grain Zn concentration. Genotypes GEC331 and GEC164 also showed improved yield under Zn treatment. Appreciable variation in grain Zn concentration among finger millet genotypes found in this study offers opportunities to improve Zn nutrition through breeding.

  4. Improved ADRC for a Maglev planar motor with a concentric winding structure

    NARCIS (Netherlands)

    Kou, Baoquan; Xing, Feng; Zhang, Chaoning; Zhang, L.; Zhou, Yiheng; Wang, Tiecheng

    2016-01-01

    In the semiconductor industry, positioning accuracy and acceleration are critical parameters. To improve the acceleration speed of a motor, this paper proposes the moving-coil maglev planar motor with a concentric winding structure. The coordinate system has been built for the multiple degrees of

  5. Design construction and analysis of solar ridge concentrator photovoltaic (PV) system to improve battery charging performance.

    Science.gov (United States)

    Narasimman, Kalaiselvan; Selvarasan, Iniyan

    2016-05-01

    A ridge concentrator photovoltaic system for a 10W multi-crystalline solar panel was designed with the concentration ratios of 1X and 2X. The ray tracing model of ridge concentrator photovoltaic system was carried out using Trace-Pro simulation. The optimum tilt angle for the concentrator PV system throughout the year was computed. The electrical parameters of the 3 panels were analyzed. The effect of temperature on the electrical performance of the panel was also studied. The reduction of voltage due to increasing panel temperature was managed by MPES type Charge controller. Glass reflector with reflectivity 0.95 was chosen as the ridge wall for the concentrator system. The maximum power outputs for the 1X and 2X panel reached were 9W and 10.5W with glass reflector. The percentage of power improvement for 1X and 2X concentrations were 22.3% and 45.8% respectively. The 2X concentrated panel connected battery takes lower time to charge compared with normal panel connected battery. Copyright © 2016. Published by Elsevier Inc.

  6. Improving the Output Power Stability of a High Concentration Photovoltaic System with Supercapacitors: A Preliminary Evaluation

    Directory of Open Access Journals (Sweden)

    Yu-Pei Huang

    2015-01-01

    Full Text Available The output power of a high concentration photovoltaic (HCPV system is very sensitive to fluctuating tracking errors and weather patterns. To help compensate this shortcoming, supercapacitors have been successfully incorporated into photovoltaic systems to improve their output power stability. This study examined the output power stability improvement of an HCPV module with a supercapacitor integrated into its circuit. Furthermore, the equivalent model of the experimental circuit is presented and analyzed. Experimental results suggest that integrating a supercapacitor into an HCPV module could improve its output power stability and further extend its acceptance angle. This paper provides preliminary data of the improvement and its evaluation method, which could be utilized for further improvements to an HCPV system.

  7. Improving the accuracy of Laplacian estimation with novel multipolar concentric ring electrodes

    Science.gov (United States)

    Ding, Quan; Besio, Walter G.

    2015-01-01

    Conventional electroencephalography with disc electrodes has major drawbacks including poor spatial resolution, selectivity and low signal-to-noise ratio that are critically limiting its use. Concentric ring electrodes, consisting of several elements including the central disc and a number of concentric rings, are a promising alternative with potential to improve all of the aforementioned aspects significantly. In our previous work, the tripolar concentric ring electrode was successfully used in a wide range of applications demonstrating its superiority to conventional disc electrode, in particular, in accuracy of Laplacian estimation. This paper takes the next step toward further improving the Laplacian estimation with novel multipolar concentric ring electrodes by completing and validating a general approach to estimation of the Laplacian for an (n + 1)-polar electrode with n rings using the (4n + 1)-point method for n ≥ 2 that allows cancellation of all the truncation terms up to the order of 2n. An explicit formula based on inversion of a square Vandermonde matrix is derived to make computation of multipolar Laplacian more efficient. To confirm the analytic result of the accuracy of Laplacian estimate increasing with the increase of n and to assess the significance of this gain in accuracy for practical applications finite element method model analysis has been performed. Multipolar concentric ring electrode configurations with n ranging from 1 ring (bipolar electrode configuration) to 6 rings (septapolar electrode configuration) were directly compared and obtained results suggest the significance of the increase in Laplacian accuracy caused by increase of n. PMID:26693200

  8. Split Nitrogen Application Improves Wheat Baking Quality by Influencing Protein Composition Rather Than Concentration.

    Science.gov (United States)

    Xue, Cheng; Auf'm Erley, Gunda Schulte; Rossmann, Anne; Schuster, Ramona; Koehler, Peter; Mühling, Karl-Hermann

    2016-01-01

    The use of late nitrogen (N) fertilization (N application at late growth stages of wheat, e.g., booting, heading or anthesis) to improve baking quality of wheat has been questioned. Although it increases protein concentration, the beneficial effect on baking quality (bread loaf volume) needs to be clearly understood. Two pot experiments were conducted aiming to evaluate whether late N is effective under controlled conditions and if these effects result from increased N rate or N splitting. Late N fertilizers were applied either as additional N or split from the basal N at late boot stage or heading in the form of nitrate-N or urea. Results showed that late N fertilization improved loaf volume of wheat flour by increasing grain protein concentration and altering its composition. Increasing N rate mainly enhanced grain protein quantitatively. However, N splitting changed grain protein composition by enhancing the percentages of gliadins and glutenins as well as certain high molecular weight glutenin subunits (HMW-GS), which led to an improved baking quality of wheat flour. The late N effects were greater when applied as nitrate-N than urea. The proportions of glutenin and x-type HMW-GS were more important than the overall protein concentration in determining baking quality. N splitting is more effective in improving wheat quality than the increase in the N rate by late N, which offers the potential to cut down N fertilization rates in wheat production systems.

  9. Split nitrogen application improves wheat baking quality by influencing protein composition rather than concentration

    Directory of Open Access Journals (Sweden)

    Cheng eXue

    2016-06-01

    Full Text Available The use of late nitrogen (N fertilization (N application at late growth stages of wheat, e.g. booting, heading or anthesis to improve baking quality of wheat has been questioned. Although it increases protein concentration, the beneficial effect on baking quality (bread loaf volume needs to be clearly understood. Two pot experiments were conducted aiming to evaluate whether late N is effective under controlled conditions and if these effects result from increased N rate or N splitting. Late N fertilizers were applied either as additional N or split from the basal N at late boot stage or heading in the form of nitrate-N or urea. Results showed that late N fertilization improved loaf volume of wheat flour by increasing grain protein concentration and altering its composition. Increasing N rate mainly enhanced grain protein quantitatively. However, N splitting changed grain protein composition by enhancing the percentages of gliadins and glutenins as well as certain high molecular weight glutenin subunits (HMW-GS, which led to an improved baking quality of wheat flour. The late N effects were greater when applied as nitrate-N than urea. The proportions of glutenin and x-type HMW-GS were more important than the overall protein concentration in determining baking quality. N splitting is more effective in improving wheat quality than the increase in the N rate by late N, which offers the potential to cut down N fertilization rates in wheat production systems.

  10. Improving the Accuracy of Laplacian Estimation with Novel Variable Inter-Ring Distances Concentric Ring Electrodes

    Directory of Open Access Journals (Sweden)

    Oleksandr Makeyev

    2016-06-01

    Full Text Available Noninvasive concentric ring electrodes are a promising alternative to conventional disc electrodes. Currently, the superiority of tripolar concentric ring electrodes over disc electrodes, in particular, in accuracy of Laplacian estimation, has been demonstrated in a range of applications. In our recent work, we have shown that accuracy of Laplacian estimation can be improved with multipolar concentric ring electrodes using a general approach to estimation of the Laplacian for an (n + 1-polar electrode with n rings using the (4n + 1-point method for n ≥ 2. This paper takes the next step toward further improving the Laplacian estimate by proposing novel variable inter-ring distances concentric ring electrodes. Derived using a modified (4n + 1-point method, linearly increasing and decreasing inter-ring distances tripolar (n = 2 and quadripolar (n = 3 electrode configurations are compared to their constant inter-ring distances counterparts. Finite element method modeling and analytic results are consistent and suggest that increasing inter-ring distances electrode configurations may decrease the truncation error resulting in more accurate Laplacian estimates compared to respective constant inter-ring distances configurations. For currently used tripolar electrode configuration, the truncation error may be decreased more than two-fold, while for the quadripolar configuration more than a six-fold decrease is expected.

  11. Improving the Accuracy of Laplacian Estimation with Novel Variable Inter-Ring Distances Concentric Ring Electrodes

    Science.gov (United States)

    Makeyev, Oleksandr; Besio, Walter G.

    2016-01-01

    Noninvasive concentric ring electrodes are a promising alternative to conventional disc electrodes. Currently, the superiority of tripolar concentric ring electrodes over disc electrodes, in particular, in accuracy of Laplacian estimation, has been demonstrated in a range of applications. In our recent work, we have shown that accuracy of Laplacian estimation can be improved with multipolar concentric ring electrodes using a general approach to estimation of the Laplacian for an (n + 1)-polar electrode with n rings using the (4n + 1)-point method for n ≥ 2. This paper takes the next step toward further improving the Laplacian estimate by proposing novel variable inter-ring distances concentric ring electrodes. Derived using a modified (4n + 1)-point method, linearly increasing and decreasing inter-ring distances tripolar (n = 2) and quadripolar (n = 3) electrode configurations are compared to their constant inter-ring distances counterparts. Finite element method modeling and analytic results are consistent and suggest that increasing inter-ring distances electrode configurations may decrease the truncation error resulting in more accurate Laplacian estimates compared to respective constant inter-ring distances configurations. For currently used tripolar electrode configuration, the truncation error may be decreased more than two-fold, while for the quadripolar configuration more than a six-fold decrease is expected. PMID:27294933

  12. Boar variability in sperm cryo-tolerance after cooling of semen in different long-term extenders at various temperatures.

    Science.gov (United States)

    Wasilewska, K; Fraser, L

    2017-10-01

    different cooling regimens, and that cooling of extended semen for a 24-h period at 10°C modulated the functions of sperm in an extender-dependent manner, rendering the cells less susceptible to cryo-induced damage. It is suggested that the findings of this study have the potential to improve the technology of boar semen cryopreservation. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Strategic purchasing reform in Estonia: Reducing inequalities in access while improving care concentration and quality.

    Science.gov (United States)

    Habicht, Triin; Habicht, Jarno; van Ginneken, Ewout

    2015-08-01

    As of 2014, the Estonian Health Insurance Fund has adopted new purchasing procedures and criteria, which it now has started to implement in specialist care. Main changes include (1) redefined access criteria based on population need rather than historical supply, which aim to achieve more equal access of providers and specialties; (2) stricter definition and use of optimal workload criteria to increase the concentration of specialist care (3) better consideration of patient movement; and (4) an increased emphasis on quality to foster quality improvement. The new criteria were first used in the contract cycle that started in 2014 and resulted in fewer contracted providers for a similar volume of care compared to the previous contract cycle. This implies that provision of specialized care has become concentrated at fewer providers. It is too early to draw firm conclusions on the impact on care quality or on actors, but the process has sparked debate on the role of selective contracting and the role of public and private providers in Estonian health care. Lastly, the Estonian experience may hold important lessons for other countries looking to overcome inequalities in access while concentrating care and improving care quality. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  14. Concentrating carbohydrates before sleep improves feeding regulation and metabolic and inflammatory parameters in mice.

    Science.gov (United States)

    Sofer, Sigal; Eliraz, Abraham; Madar, Zecharia; Froy, Oren

    2015-10-15

    New evidance highlights the importance of food timing. Recently, we showed that a low-calorie diet with carbohydrates eaten mostly at dinner changed diurnal hormone secretion and led to greater weight loss and improved metabolic status in obese people. Herein, we set out to test whether concentrated-carbohydrates diet (CCD), in which carbohydrates are fed only before sleep, leads to an improved metabolic status in mouse hypothalamus and peripheral tissues. Diet-induced obese mice were given concentrated or distributed carbohydrate diet for 6 weeks. Obese mice fed CCD ate 8.3% less, were 9.3% leaner and had 39.7% less fat mass. Leptin, ghrelin and adiponectin displayed altered secretion. In addition, these mice exhibited an improved biochemical and inflammatory status. In the hypothalamus, anorexigenic signals were up-regulated and orexigenic signals were down-regulated. In peripheral tissues, CCD promoted adiponectin signaling, repressed gluconeogenesis, enhanced lipid oxidation and lowered inflammation, thus ameliorating the major risk factors of obesity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Microfluidic Purification and Concentration of Malignant Pleural Effusions for Improved Molecular and Cytomorphological Diagnostics

    Science.gov (United States)

    Go, Derek E.; Talati, Ish; Ying, Yong; Rao, Jianyu; Kulkarni, Rajan P.; Di Carlo, Dino

    2013-01-01

    Evaluation of pleural fluids for metastatic cells is a key component of diagnostic cytopathology. However, a large background of smaller leukocytes and/or erythrocytes can make accurate diagnosis difficult and reduce specificity in identification of mutations of interest for targeted anti-cancer therapies. Here, we describe an automated microfluidic system (Centrifuge Chip) which employs microscale vortices for the size-based isolation and concentration of cancer cells and mesothelial cells from a background of blood cells. We are able to process non-diluted pleural fluids at 6 mL/min and enrich target cells significantly over the background; we achieved improved purity in all patient samples analyzed. The resulting isolated and viable cells are readily available for immunostaining, cytological analysis, and detection of gene mutations. To demonstrate the utility towards aiding companion diagnostics, we also show improved detection accuracy of KRAS gene mutations in lung cancer cells processed using the Centrifuge Chip, leading to an increase in the area under the curve (AUC) of the receiver operating characteristic from 0.90 to 0.99. The Centrifuge Chip allows for rapid concentration and processing of large volumes of bodily fluid samples for improved cytological diagnosis and purification of cells of interest for genetic testing, which will be helpful for enhancing diagnostic accuracy. PMID:24205153

  16. Enhanced nutrition improves growth and increases blood adiponectin concentrations in very low birth weight infants

    Directory of Open Access Journals (Sweden)

    Elin W. Blakstad

    2016-12-01

    Full Text Available Background: Adequate nutrient supply is essential for optimal postnatal growth in very low birth weight (VLBW, birth weight<1,500 g infants. Early growth may influence the risk of metabolic syndrome later in life. Objective: To evaluate growth and blood metabolic markers (adiponectin, leptin, and insulin-like growth factor-1 (IGF-1 in VLBW infants participating in a randomized nutritional intervention study. Design: Fifty VLBW infants were randomized to an enhanced nutrient supply or a standard nutrient supply. Thirty-seven infants were evaluated with growth measurements until 2 years corrected age (CA. Metabolic markers were measured at birth and 5 months CA. Results: Weight gain and head growth were different in the two groups from birth to 2 years CA (weight gain: pinteraction=0.006; head growth: pinteraction=0.002. The intervention group improved their growth z-scores after birth, whereas the control group had a pronounced decline, followed by an increase and caught up with the intervention group after discharge. At 5 months CA, adiponectin concentrations were higher in the intervention group and correlated with weight gain before term (r=0.35 and nutrient supply (0.35≤r≤0.45. Leptin concentrations correlated with weight gain after term and IGF-1 concentrations with length growth before and after term and head growth after term (0.36≤r≤0.53. Conclusion: Enhanced nutrient supply improved early postnatal growth and may have prevented rapid catch-up growth later in infancy. Adiponectin concentration at 5 months CA was higher in the intervention group and correlated positively with early weight gain and nutrient supply. Early nutrition and growth may affect metabolic markers in infancy.Clinical Trial Registration (ClinicalTrials.gov no.: NCT01103219

  17. Improvements of neutron activation techniques for the determination of fissile material concentrations

    International Nuclear Information System (INIS)

    Papadopoulos, N.N.

    1987-01-01

    Certain experimental improvements, as variable sample size and irradiation position, automation and flexibility in radiation detection, broaden the measurable concentration range, increase the possible rate and accuracy of analysis and enlarge the application range of home-made nuclear analyzer for fissile material analysis by delayed fission neutron counting and for short-lived multielement analysis by neutron activation gamma-ray spectrometry. Intercomparisons of results by various methods and laboratories show the need for regular checks of techniques to ensure reliable measurements. (author)

  18. Critical Synergistic Concentration of Lecithin Phospholipids Improves the Antimicrobial Activity of Eugenol against Escherichia coli

    Science.gov (United States)

    Zhang, Haoshu; Dudley, Edward G.

    2017-01-01

    ABSTRACT In this study, the effect of individual lecithin phospholipids on the antimicrobial properties of eugenol against Escherichia coli C600 was investigated. We tested five major phospholipids common in soy or egg lecithin (1,2-dihexadecanoyl-sn-glycero-3-phosphocholine [DPPC], 1,2-dioctadecanoyl-sn-glycero-3-phosphocholine [DSPC], 1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine [DPPE], 1,2-dihexadecanoyl-sn-glycero-3-phosphate [sodium salt] [DPPA], and 1,2-dihexadecanoyl-sn-glycero-3-phospho-l-serine [DPPS]) and one synthetic cationic phospholipid (1,2-dioctadecanoyl-sn-glycero-3-ethylphosphocholine [18:0 EPC]). Among the six phospholipids, DPPC, DSPC, DPPE, DPPA, and the cationic 18:0 EPC showed critical synergistic concentrations that significantly improved the inactivation effect of eugenol against E. coli after 30 min of exposure. At the critical synergistic concentration, an additional ca. 0.4 to 1.9 log reduction (ca. 0.66 to 2.17 log CFU/ml reduction) in the microbial population was observed compared to eugenol-only (control) treatments (ca. 0.25 log reduction). In all cases, increasing the phospholipid amount above the critical synergistic concentration (which was different for each phospholipid) resulted in antimicrobial properties similar to those seen with the eugenol-only (control) treatments. DPPS did not affect the antimicrobial properties of eugenol at the tested concentrations. The critical synergistic concentration of phospholipids was correlated with their critical micelle concentrations (CMC). IMPORTANCE Essential oils (EOs) are naturally occurring antimicrobials, with limited use in food due to their hydrophobicity and strong aroma. Lecithin is used as a natural emulsifier to stabilize EOs in aqueous systems. We previously demonstrated that, within a narrow critical-concentration window, lecithin can synergistically enhance the antimicrobial properties of eugenol. Since lecithin is a mixture of different phospholipids, we aimed to

  19. Critical Synergistic Concentration of Lecithin Phospholipids Improves the Antimicrobial Activity of Eugenol against Escherichia coli.

    Science.gov (United States)

    Zhang, Haoshu; Dudley, Edward G; Harte, Federico

    2017-11-01

    In this study, the effect of individual lecithin phospholipids on the antimicrobial properties of eugenol against Escherichia coli C600 was investigated. We tested five major phospholipids common in soy or egg lecithin (1,2-dihexadecanoyl-sn-glycero-3-phosphocholine [DPPC], 1,2-dioctadecanoyl-sn-glycero-3-phosphocholine [DSPC], 1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine [DPPE], 1,2-dihexadecanoyl-sn-glycero-3-phosphate [sodium salt] [DPPA], and 1,2-dihexadecanoyl-sn-glycero-3-phospho-l-serine [DPPS]) and one synthetic cationic phospholipid (1,2-dioctadecanoyl-sn-glycero-3-ethylphosphocholine [18:0 EPC]). Among the six phospholipids, DPPC, DSPC, DPPE, DPPA, and the cationic 18:0 EPC showed critical synergistic concentrations that significantly improved the inactivation effect of eugenol against E. coli after 30 min of exposure. At the critical synergistic concentration, an additional ca. 0.4 to 1.9 log reduction (ca. 0.66 to 2.17 log CFU/ml reduction) in the microbial population was observed compared to eugenol-only (control) treatments (ca. 0.25 log reduction). In all cases, increasing the phospholipid amount above the critical synergistic concentration (which was different for each phospholipid) resulted in antimicrobial properties similar to those seen with the eugenol-only (control) treatments. DPPS did not affect the antimicrobial properties of eugenol at the tested concentrations. The critical synergistic concentration of phospholipids was correlated with their critical micelle concentrations (CMC). IMPORTANCE Essential oils (EOs) are naturally occurring antimicrobials, with limited use in food due to their hydrophobicity and strong aroma. Lecithin is used as a natural emulsifier to stabilize EOs in aqueous systems. We previously demonstrated that, within a narrow critical-concentration window, lecithin can synergistically enhance the antimicrobial properties of eugenol. Since lecithin is a mixture of different phospholipids, we aimed to identify

  20. Improved ADRC for a Maglev Planar Motor with a Concentric Winding Structure

    Directory of Open Access Journals (Sweden)

    Baoquan Kou

    2016-12-01

    Full Text Available In the semiconductor industry, positioning accuracy and acceleration are critical parameters. To improve the acceleration speed of a motor, this paper proposes the moving-coil maglev planar motor with a concentric winding structure. The coordinate system has been built for the multiple degrees of freedom movement system. The Lorenz force method has been applied to solve its electromagnetic model. The real-time solving of the generalized inverse matrix of factors can realize the decoupling of the winding current. When the maglev height changes, the electromagnetic force and torque decreases exponentially with the increase of the air gap. To decrease the influence on control system performance by the internal model change and the external disturbance, this paper proposes an improved active disturbance rejection control (ADRC to design the controller. This new controller overcomes the jitter phenomenon due to the turning point for the traditional ADRC, thus it is more suitable for the maglev control system. The comparison between ADRC and the improved ADRC has been conducted, the result of which shows the improved ADRC has greater robustness.

  1. Improving solar-pumped laser efficiency by a ring-array concentrator

    Science.gov (United States)

    Tibúrcio, Bruno D.; Liang, Dawei; Almeida, Joana; Matos, Rodrigo; Vistas, Cláudia R.

    2018-01-01

    We report here a compact pumping scheme for achieving large improvement in collection and conversion efficiency of a Nd:YAG solar-pumped laser by an innovative ring-array solar concentrator. An aspheric fused silica lens was used to further concentrate the solar radiation from the focal region of the 1.5-m-diameter ring-array concentrator to a 5.0-mm-diameter, 20-mm-length Nd:YAG single-crystal rod within a conical-shaped pump cavity, enabling multipass pumping to the laser rod. 67.3-W continuous-wave solar laser power was numerically calculated, corresponding to 38.2-W / m2 solar laser collection efficiency, being 1.22 and 1.27 times more than the state-of-the-art records by both heliostat-parabolic mirror and Fresnel lens solar laser systems, respectively. 4.0% conversion efficiency and 0.021-W brightness figure of merit were also numerically obtained, corresponding to 1.25 and 1.62 times enhancement over the previous records, respectively. The influence of tracking error on solar laser output power was also analyzed.

  2. Electro-encephalogram based brain-computer interface: improved performance by mental practice and concentration skills.

    Science.gov (United States)

    Mahmoudi, Babak; Erfanian, Abbas

    2006-11-01

    Mental imagination is the essential part of the most EEG-based communication systems. Thus, the quality of mental rehearsal, the degree of imagined effort, and mind controllability should have a major effect on the performance of electro-encephalogram (EEG) based brain-computer interface (BCI). It is now well established that mental practice using motor imagery improves motor skills. The effects of mental practice on motor skill learning are the result of practice on central motor programming. According to this view, it seems logical that mental practice should modify the neuronal activity in the primary sensorimotor areas and consequently change the performance of EEG-based BCI. For developing a practical BCI system, recognizing the resting state with eyes opened and the imagined voluntary movement is important. For this purpose, the mind should be able to focus on a single goal for a period of time, without deviation to another context. In this work, we are going to examine the role of mental practice and concentration skills on the EEG control during imaginative hand movements. The results show that the mental practice and concentration can generally improve the classification accuracy of the EEG patterns. It is found that mental training has a significant effect on the classification accuracy over the primary motor cortex and frontal area.

  3. Application of time-resolved glucose concentration photoacoustic signals based on an improved wavelet denoising

    Science.gov (United States)

    Ren, Zhong; Liu, Guodong; Huang, Zhen

    2014-10-01

    Real-time monitoring of blood glucose concentration (BGC) is a great important procedure in controlling diabetes mellitus and preventing the complication for diabetic patients. Noninvasive measurement of BGC has already become a research hotspot because it can overcome the physical and psychological harm. Photoacoustic spectroscopy is a well-established, hybrid and alternative technique used to determine the BGC. According to the theory of photoacoustic technique, the blood is irradiated by plused laser with nano-second repeation time and micro-joule power, the photoacoustic singals contained the information of BGC are generated due to the thermal-elastic mechanism, then the BGC level can be interpreted from photoacoustic signal via the data analysis. But in practice, the time-resolved photoacoustic signals of BGC are polluted by the varities of noises, e.g., the interference of background sounds and multi-component of blood. The quality of photoacoustic signal of BGC directly impacts the precision of BGC measurement. So, an improved wavelet denoising method was proposed to eliminate the noises contained in BGC photoacoustic signals. To overcome the shortcoming of traditional wavelet threshold denoising, an improved dual-threshold wavelet function was proposed in this paper. Simulation experimental results illustrated that the denoising result of this improved wavelet method was better than that of traditional soft and hard threshold function. To varify the feasibility of this improved function, the actual photoacoustic BGC signals were test, the test reslut demonstrated that the signal-to-noises ratio(SNR) of the improved function increases about 40-80%, and its root-mean-square error (RMSE) decreases about 38.7-52.8%.

  4. Final Report on the Operation and Maintenance Improvement Program for Concentrating Solar Power Plants

    International Nuclear Information System (INIS)

    Cohen, Gilbert E.; Kearney, David W.; Kolb, Gregory J.

    1999-01-01

    This report describes the results of a six-year, $6.3 million project to reduce operation and maintenance (O ampersand M) costs at power plants employing concentrating solar power (CSP) technology. Sandia National Laboratories teamed with KJC Operating Company to implement the O ampersand M Improvement Program. O ampersand M technologies developed during the course of the program were demonstrated at the 150-MW Kramer Junction solar power park located in Boron, California. Improvements were made in the following areas: (a) efficiency of solar energy collection, (b) O ampersand M information management, (c) reliability of solar field flow loop hardware, (d) plant operating strategy, and (e) cost reduction associated with environmental issues. A 37% reduction in annual O ampersand M costs was achieved. Based on the lessons learned, an optimum solar- field O ampersand M plan for future CSP plants is presented. Parabolic trough solar technology is employed at Kramer Junction. However, many of the O ampersand M improvements described in the report are also applicable to CSP plants based on solar power tower or dish/engine concepts

  5. Final Report on the Operation and Maintenance Improvement Program for Concentrating Solar Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Cohen Gilbert E.; Kearney, David W.; Kolb, Gregory J.

    1999-06-01

    This report describes the results of a six-year, $6.3 million project to reduce operation and maintenance (O&M) costs at power plants employing concentrating solar power (CSP) technology. Sandia National Laboratories teamed with KJC Operating Company to implement the O&M Improvement Program. O&M technologies developed during the course of the program were demonstrated at the 150-MW Kramer Junction solar power park located in Boron, California. Improvements were made in the following areas: (a) efficiency of solar energy collection, (b) O&M information management, (c) reliability of solar field flow loop hardware, (d) plant operating strategy, and (e) cost reduction associated with environmental issues. A 37% reduction in annual O&M costs was achieved. Based on the lessons learned, an optimum solar- field O&M plan for future CSP plants is presented. Parabolic trough solar technology is employed at Kramer Junction. However, many of the O&M improvements described in the report are also applicable to CSP plants based on solar power tower or dish/engine concepts.

  6. An improved procedure for determining grain boundary diffusion coefficients from averaged concentration profiles

    Science.gov (United States)

    Gryaznov, D.; Fleig, J.; Maier, J.

    2008-03-01

    Whipple's solution of the problem of grain boundary diffusion and Le Claire's relation, which is often used to determine grain boundary diffusion coefficients, are examined for a broad range of ratios of grain boundary to bulk diffusivities Δ and diffusion times t. Different reasons leading to errors in determining the grain boundary diffusivity (DGB) when using Le Claire's relation are discussed. It is shown that nonlinearities of the diffusion profiles in lnCav-y6/5 plots and deviations from "Le Claire's constant" (-0.78) are the major error sources (Cav=averaged concentration, y =coordinate in diffusion direction). An improved relation (replacing Le Claire's constant) is suggested for analyzing diffusion profiles particularly suited for small diffusion lengths (short times) as often required in diffusion experiments on nanocrystalline materials.

  7. Lithium-induced NDI: acetazolamide reduces polyuria but does not improve urine concentrating ability.

    Science.gov (United States)

    de Groot, Theun; Doornebal, Joan; Christensen, Birgitte M; Cockx, Simone; Sinke, Anne P; Baumgarten, Ruben; Bedford, Jennifer J; Walker, Robert J; Wetzels, Jack F M; Deen, Peter M T

    2017-09-01

    Lithium is the mainstay treatment for patients with bipolar disorder, but it generally causes nephrogenic diabetes insipidus (NDI), a disorder in which the renal urine concentrating ability has become vasopressin insensitive. Li-NDI is caused by lithium uptake by collecting duct principal cells and downregulation of aquaporin-2 (AQP2) water channels, which are essential for water uptake from tubular urine. Recently, we found that the prophylactic administration of acetazolamide to mice effectively attenuated Li-NDI. To evaluate whether acetazolamide might benefit lithium-treated patients, we administered acetazolamide to mice with established Li-NDI and six patients with a lithium-induced urinary concentrating defect. In mice, acetazolamide partially reversed lithium-induced polyuria and increased urine osmolality, which, however, did not coincide with increased AQP2 abundances. In patients, acetazolamide led to the withdrawal of two patients from the study due to side effects. In the four remaining patients acetazolamide did not lead to clinically relevant changes in maximal urine osmolality. Urine output was also not affected, although none of these patients demonstrated overt lithium-induced polyuria. In three out of four patients, acetazolamide treatment increased serum creatinine levels, indicating a decreased glomerular filtration rate (GFR). Strikingly, these three patients also showed a decrease in systemic blood pressure. All together, our data reveal that acetazolamide does not improve the urinary concentrating defect caused by lithium, but it lowers the GFR, likely explaining the reduced urine output in our mice and in a recently reported patient with lithium-induced polyuria. The reduced GFR in patients prone to chronic kidney disease development, however, warrants against application of acetazolamide in Li-NDI patients without long-term (pre)clinical studies. Copyright © 2017 the American Physiological Society.

  8. Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adults.

    Science.gov (United States)

    Engler, Mary B; Engler, Marguerite M; Chen, Chung Y; Malloy, Mary J; Browne, Amanda; Chiu, Elisa Y; Kwak, Ho-Kyung; Milbury, Paul; Paul, Steven M; Blumberg, Jeffrey; Mietus-Snyder, Michele L

    2004-06-01

    Dark chocolate derived from the plant (Theobroma cacao) is a rich source of flavonoids. Cardioprotective effects including antioxidant properties, inhibition of platelet activity, and activation of endothelial nitric oxide synthase have been ascribed to the cocoa flavonoids. To investigate the effects of flavonoid-rich dark chocolate on endothelial function, measures of oxidative stress, blood lipids, and blood pressure in healthy adult subjects. The study was a randomized, double-blind, placebo-controlled design conducted over a 2 week period in 21 healthy adult subjects. Subjects were randomly assigned to daily intake of high-flavonoid (213 mg procyanidins, 46 mg epicatechin) or low-flavonoid dark chocolate bars (46 g, 1.6 oz). High-flavonoid chocolate consumption improved endothelium-dependent flow-mediated dilation (FMD) of the brachial artery (mean change = 1.3 +/- 0.7%) as compared to low-flavonoid chocolate consumption (mean change = -0.96 +/- 0.5%) (p = 0.024). No significant differences were noted in the resistance to LDL oxidation, total antioxidant capacity, 8-isoprostanes, blood pressure, lipid parameters, body weight or body mass index (BMI) between the two groups. Plasma epicatechin concentrations were markedly increased at 2 weeks in the high-flavonoid group (204.4 +/- 18.5 nmol/L, p < or = 0.001) but not in the low-flavonoid group (17.5 +/- 9 nmol/L, p = 0.99). Flavonoid-rich dark chocolate improves endothelial function and is associated with an increase in plasma epicatechin concentrations in healthy adults. No changes in oxidative stress measures, lipid profiles, blood pressure, body weight or BMI were seen.

  9. Application of porous medium for efficiency improvement of a concentrated solar air heating system

    Science.gov (United States)

    Prasartkaew, Boonrit

    2018-01-01

    The objective of this study is to evaluate the thermal efficiency of a concentrated solar collector for a high temperature air heating system. The proposed system consists of a 25-m2 focused multi-flat-mirror solar heliostat equipped with a porous medium solar collector/receiver which was installed on the top of a 3-m tower, called ‘tower receiver’. To know how the system efficiency cloud be improved by using porous medium, the proposed system with and without porous medium were tested and the comparative study was performed. The experimental results reveal that, for the proposed system, application of porous medium is promising, the efficiency can be increased about 2 times compared to the conventional one. In addition, due to the porous medium used in this study was the waste material with very low cost. It can be summarized that the substantial efficiency improvement with very low investment cost of the proposed system seem to be a vital measures for addressing the energy issues.

  10. Efficiency improvement of a concentrated solar receiver for water heating system using porous medium

    Science.gov (United States)

    Prasartkaew, Boonrit

    2018-01-01

    This experimental study aims at investigating on the performance of a high temperature solar water heating system. To approach the high temperature, a porous-medium concentrated solar collector equipped with a focused solar heliostat were proposed. The proposed system comprised of two parts: a 0.7x0.7-m2 porous medium receiver, was installed on a 3-m tower, and a focused multi-flat-mirror solar heliostat with 25-m2 aperture area. The porous medium used in this study was the metal swarf or metal waste from lathing process. To know how the system efficiency could be improved by using such porous medium, the proposed system with- and without-porous medium were tested and the comparative study was performed. The experimental results show that, using porous medium for enhancing the heat transfer mechanism, the system thermal efficiency was increased about 25%. It can be concluded that the efficiency of the proposed system can be substantially improved by using the porous medium.

  11. ASSESSMENT FORM - NEW IMPROVEMENT OF ACTIONS: CONCENTRATION AND RESEARCH AREAS / CURRICULUM STRUCTURE / FUNDRAISING

    Directory of Open Access Journals (Sweden)

    Iracema MP Calderon

    Full Text Available Objective: This review aims to develop a critical and current analysis of the basic structure of a Postgraduate program for proposing improvement actions and new evaluation criteria. Method: To examine the items that are areas of concentration (AC, research lines (LP, research projects (PP, curricular structure and fundraising were consulted the Area Document, the 2013 Evaluation Report and the Assessment Sheets of Medicine III programs, evaluated in the 2010-2012 period. Results: Consistency is recommended especially among AC, LP and PP, with genuine link between activities and permanent teachers skills and based on structured curriculum in the education of the student. The Program Proposal interfere, and much, in qualifying a program. The curriculum should provide subsidy to the formation of the researcher, through the core subjects, and development of PP, being the concept of disciplines to support lines and research projects. Fundraise should be set out in research projects and in the CV-Lattes. The area recommended that at least 40-50% of permanent teachers present fundraising and the minimum 20-25% of these teachers to have productivity scholarship PQ / CNPq during the triennium. Conclusion: It is necessary to promote wide discussion and find a consensus denominator for these issues. The actions should contribute to the improvement of evaluation forms and certainly for the qualification of the programs but graduate.

  12. Highly improved synthesis of gold nanobipyramids by tuning the concentration of hydrochloric acid

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Ying; Zhu, Jian; Li, Jianjun; Zhao, Junwu, E-mail: nanoptzhao@163.com [Xi’an Jiaotong University, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology (China)

    2016-07-15

    Fabrication of gold nanobipyramids (Au BPs) has attracted great attention because they exhibit more advantageous plasmonic properties. In this study, Au BPs were synthesized by the well-known seeded growth in the presence of hydrochloric acid (HCl). The effects of the ingredients, including HCl, silver nitrate (AgNO{sub 3}), l-Ascorbic acid (AA), and seeds on the structure and yield of the Au BPs were systemically investigated. The results showed that the abundant HCl could improve the yield of Au BPs and decrease the longitudinal surface plasmon resonance wavelength. Under the circumstance of higher concentration of AA and AgNO{sub 3}, more byproducts were resulted. In addition, the effect of HCl under different ratios of seed solution to AA has also been studied. The results showed that the yield was less sensitive to HCl when the amount of seed solution was small. If substantial AA was added to the system, then abundant HCl should be introduced correspondingly to improve the yield of Au BPs.

  13. High Concentrations of Sodium Chloride Improve Microbicidal Activity of Ibuprofen against Common Cystic Fibrosis Pathogens

    Directory of Open Access Journals (Sweden)

    Adrián J. Muñoz

    2018-05-01

    Full Text Available Ibuprofen (IBU-H, a widely used anti-inflammatory, also shows a marked antimicrobial effect against several bacterial species, including those involved in cystic fibrosis such as Pseudomona aeruginosa, methicillin resistant Staphylococcus aureus and Burkholderia cepacia complex. Additionally, our results show significant synergy between water soluble Na-ibuprofen (IBU-Na and ionic strength. Salt concentrations above 0.5 M modify the zeta potential promoting the action of Na-IBU; thus, with 1 M sodium chloride, IBU-Na is ten times more efficient than in the absence of ionic strength, and the minimum effective contact time is reduced from hours to minutes. In short time periods, where neither IBU-Na nor controls with 1 M NaCl show activity, the combination of both leads to a reduction in the bacterial load. We also analyzed whether the changes caused by salt on the bacterial membrane also promoted the activity of other microbicide compounds used in cystic fibrosis like gentamicin, tobramycin and phosphomycin. The results show that the presence of ionic strength only enhanced the bactericidal activity of the amphipathic molecule of IBU-Na. In this respect, the effect of saline concentration was also reflected in the surface properties of IBU-Na, where, in addition to the clear differences observed between 145 mM and 1 M, singular behaviors were also found, different in each condition. The combination of anti-inflammatory activity and this improved bactericidal effect of Na-IBU in hypertonic solution provides a new alternative for the treatment of respiratory infections of fibrotic patients based on known and widely used compounds.

  14. Improved OAM-Based Radar Targets Detection Using Uniform Concentric Circular Arrays

    Directory of Open Access Journals (Sweden)

    Mingtuan Lin

    2016-01-01

    Full Text Available Without any relative moves or beam scanning, the novel Orbital-Angular-Momentum- (OAM- based radar targets detection technique using uniform concentric circular arrays (UCCAs shows the azimuthal estimation ability, which provides new perspective for radar system design. However, the main estimation method, that is, Fast Fourier Transform (FFT, under this scheme suffers from low resolution. As a solution, this paper rebuilds the OAM-based radar targets detection model and introduces the multiple signal classification (MUSIC algorithm to improve the resolution for detecting targets within the main lobes. The spatial smoothing technique is proposed to tackle the coherent problem brought by the proposed model. Analytical study and simulation demonstrate the superresolution estimation capacity the MUSIC algorithm can achieve for detecting targets within the main lobes. The performance of the MUSIC algorithm to detect targets not illuminated by the main lobes is further evaluated. Despite the fact that MUSIC algorithm loses the resolution advantage under this case, its estimation is more robust than that of the FFT method. Overall, the proposed MUSIC algorithm for the OAM-based radar system demonstrates the superresolution ability for detecting targets within the main lobes and good robustness for targets out of the main lobes.

  15. Improved high temperature solar absorbers for use in Concentrating Solar Power central receiver applications.

    Energy Technology Data Exchange (ETDEWEB)

    Stechel, Ellen Beth; Ambrosini, Andrea; Hall, Aaron Christopher; Lambert, Timothy L.; Staiger, Chad Lynn; Bencomo, Marlene

    2010-09-01

    Concentrating solar power (CSP) systems use solar absorbers to convert the heat from sunlight to electric power. Increased operating temperatures are necessary to lower the cost of solar-generated electricity by improving efficiencies and reducing thermal energy storage costs. Durable new materials are needed to cope with operating temperatures >600 C. The current coating technology (Pyromark High Temperature paint) has a solar absorptance in excess of 0.95 but a thermal emittance greater than 0.8, which results in large thermal losses at high temperatures. In addition, because solar receivers operate in air, these coatings have long term stability issues that add to the operating costs of CSP facilities. Ideal absorbers must have high solar absorptance (>0.95) and low thermal emittance (<0.05) in the IR region, be stable in air, and be low-cost and readily manufacturable. We propose to utilize solution-based synthesis techniques to prepare intrinsic absorbers for use in central receiver applications.

  16. Improved R2* liver iron concentration assessment using a novel fuzzy c-mean clustering scheme

    International Nuclear Information System (INIS)

    Saiviroonporn, Pairash; Viprakasit, Vip; Krittayaphong, Rungroj

    2015-01-01

    In thalassemia patients, R2* liver iron concentration (LIC) measurement is a common clinical tool for assessing iron overload and for determining necessary chelator dose and evaluating its efficacy. Despite the importance of accurate LIC measurement, existing methods suffer from LIC variability, especially at the severe iron overload range due to inclusion of vessel parts in LIC calculation. In this study, we build upon previous Fuzzy C-Mean (FCM) clustering work to formulate a scheme with superior performance in segmenting vessel pixels from the parenchyma. Our method (MIX-FCM) combines our novel 2D-FCM with the existing 1D-FCM algorithm. This study further assessed possible optimal clustering parameters (OP scheme) and proposed a semi-automatic (SA) scheme for routine clinical application. Segmentation of liver parenchyma and vessels was performed on T2* images and their LIC maps in 196 studies from 147 thalassemia major patients. We used manual segmentation as the reference. 1D-FCM clustering was performed on the acquired image alone and 2D-FCM used both the acquired image and its LIC data. To execute the MIX-FCM method, the best outcome (OP-MIX-FCM) was selected from the aforementioned methods and was compared to the SA-MIX-FCM scheme. We used the percent value of the normalized interquartile range (nIQR) to its median to evaluate the variability of all methods. 2D-FCM clustering is more effective than 1D-FCM clustering at the severe overload range only, but inferior for other ranges (where 1D-FCM provides suitable results). This complementary performance between the two methods allows MIX-FCM to improve results for all ranges. OP-MIX-FCM clustering error was 2.1 ± 2.3 %, compared with 10.3 ± 9.9 % and 7.0 ± 11.9 % from 1D- and 2D-FCM clustering, respectively. SA-MIX-FCM result was comparable to OP-MIX-FCM result, with both schemes showing ability to decrease overall nIQR by approximately 30 %. Our proposed 2D-FCM algorithm is not as superior to 1D-FCM as

  17. Improved integrating-sphere throughput with a lens and nonimaging concentrator.

    Science.gov (United States)

    Chenault, D B; Snail, K A; Hanssen, L M

    1995-12-01

    A reflectometer design utilizing an integrating sphere with a lens and nonimaging concentrator is described. Compared with previous designs where a collimator was used to restrict the detector field of view, the concentrator-lens combination significantly increases the throughput of the reflectometer. A procedure for designing lens-concentrators is given along with the results of parametric studies. The measured angular response of a lens-concentrator system is compared with ray-trace predictions and with the response of an ideal system.

  18. Improved sulphate removal rates at increased sulphide concentration in the sulphidogenic bioreactor

    CSIR Research Space (South Africa)

    Greben, HA

    2005-07-01

    Full Text Available The product of the biological sulphate reduction is sulphide. High concentrations of molecular H2S(g) can be inhibitory for microbial activity, especially at a reactor pH of 6 to 7. This paper focuses on the effect of high sulphide concentrations...

  19. [Effect of microbial nutrient concentration on improvement of municipal sewage sludge dewaterability through bioleaching].

    Science.gov (United States)

    Song, Yong-wei; Liu, Fen-wu; Zhou, Li-xiang

    2012-08-01

    In this study, shaking flask batch experiments and practical engineering application tests were performed to investigate the effect of microbial nutrient concentration on the dewaterability of municipal sewage sludge with 2%, 3%, 4% and 5% solid contents via bioleaching. Meanwhile, the changes of pH value and the utilization efficiency of microbial nutrients during bioleaching were analyzed in this study. The results showed that the pH value decreased gradually at the beginning and then maintained a stable state in the treatments with different solid contents, and the nutrients were completely used up by the microorganisms after 2 days of bioleaching. It was found that the SRF of 2%, 3%, 4%, 5% sludges decreased quickly and then rose gradually with the extension of bioleaching time. In addition, the higher solid content the greater the increase. It was determined that the optimum microbial nutrient dosage for sludge with solid content of 2%, 3%, 4% and 5% were 3.0 g x L(-1), 4.5 g x L(-1), 8.3 g x L(-1) and 12.8 g x L(-1) respectively. At this point, the lowest SRF of sludge with each solid content were 0.61 x 10(12) m x kg(-1), 1.22 x 10(12) m x kg(-1), 3.09 x 10(12) m x kg(-1) and 4.83 x 10(12) m x kg(-1), respectively. Through the engineering application, it was showed that diluting the solid content of sewage sludge from 5% to 3% before bioleaching was feasible. It could not only improve the dewaterability of bioleached sewage sludge (the SRF declined from 3.29 x 10(12) m x kg(-1) to 1.10 x 10(12) m x kg(-1)), but also shorten the sludge nutrient time (shortened from 4 days to 2.35 days) and reduce the operation costs. Therefore, the results of this study have important significance for the engineering application of bioleaching of municipal sewage sludge with high solid content.

  20. Measurements of neonatal bilirubin and albumin concentrations : a need for improvement and quality control

    NARCIS (Netherlands)

    van Imhoff, Deirdre E.; Dijk, Peter H.; Weykamp, Cas W.; Cobbaert, Christa M.; Hulzebos, Christian V.

    Accurate and precise bilirubin and albumin measurements are essential for proper management of jaundiced neonates. Data hereon are lacking for Dutch laboratories. We aimed to determine variability of measurements of bilirubin and albumin concentrations typical for (preterm) neonates. Aqueous, human

  1. Measurements of neonatal bilirubin and albumin concentrations: a need for improvement and quality control

    NARCIS (Netherlands)

    Imhoff, D.E. van; Dijk, P.H.; Weykamp, C.W.; Cobbaert, C.M.; Hulzebos, C.V.; Liem, K.D.; et al.,

    2011-01-01

    Accurate and precise bilirubin and albumin measurements are essential for proper management of jaundiced neonates. Data hereon are lacking for Dutch laboratories. We aimed to determine variability of measurements of bilirubin and albumin concentrations typical for (preterm) neonates. Aqueous, human

  2. Assimilation of ice and water observations from SAR imagery to improve estimates of sea ice concentration

    Directory of Open Access Journals (Sweden)

    K. Andrea Scott

    2015-09-01

    Full Text Available In this paper, the assimilation of binary observations calculated from synthetic aperture radar (SAR images of sea ice is investigated. Ice and water observations are obtained from a set of SAR images by thresholding ice and water probabilities calculated using a supervised maximum likelihood estimator (MLE. These ice and water observations are then assimilated in combination with ice concentration from passive microwave imagery for the purpose of estimating sea ice concentration. Due to the fact that the observations are binary, consisting of zeros and ones, while the state vector is a continuous variable (ice concentration, the forward model used to map the state vector to the observation space requires special consideration. Both linear and non-linear forward models were investigated. In both cases, the assimilation of SAR data was able to produce ice concentration analyses in closer agreement with image analysis charts than when assimilating passive microwave data only. When both passive microwave and SAR data are assimilated, the bias between the ice concentration analyses and the ice concentration from ice charts is 19.78%, as compared to 26.72% when only passive microwave data are assimilated. The method presented here for the assimilation of SAR data could be applied to other binary observations, such as ice/water information from visual/infrared sensors.

  3. Comparison of Photometer with Improved Neubauer Hemocytometer and Makler Counting Chamber for Sperm Concentration Measurement in Cattle

    Directory of Open Access Journals (Sweden)

    Naima Atiq, Nemat Ullah1*, S. M. H. Andrabi2 and Shamim Akhter

    2011-01-01

    Full Text Available The present study was designed to compare the photometer (Lp 300 SDM Minitüb GmHb with improved Neubauer hemocytometer and Makler counting chamber for sperm concentration measurement in cow bulls. Data were based on 35 cow bull semen samples. The average sperm concentrations (109/ml determined by photometer, hemocytometer and Makler chamber were 1.35±0.72, 1.17±0.53 and 1.49±0.60, respectively. Analysis of variance revealed that there was no difference among the three techniques of sperm concentration measurement of same semen samples in cow bulls. It was concluded that the use of photometer in semen evaluation for sperm concentration reduced chances of human error and time consumption effectively.

  4. An improved geographically weighted regression model for PM2.5 concentration estimation in large areas

    Science.gov (United States)

    Zhai, Liang; Li, Shuang; Zou, Bin; Sang, Huiyong; Fang, Xin; Xu, Shan

    2018-05-01

    Considering the spatial non-stationary contributions of environment variables to PM2.5 variations, the geographically weighted regression (GWR) modeling method has been using to estimate PM2.5 concentrations widely. However, most of the GWR models in reported studies so far were established based on the screened predictors through pretreatment correlation analysis, and this process might cause the omissions of factors really driving PM2.5 variations. This study therefore developed a best subsets regression (BSR) enhanced principal component analysis-GWR (PCA-GWR) modeling approach to estimate PM2.5 concentration by fully considering all the potential variables' contributions simultaneously. The performance comparison experiment between PCA-GWR and regular GWR was conducted in the Beijing-Tianjin-Hebei (BTH) region over a one-year-period. Results indicated that the PCA-GWR modeling outperforms the regular GWR modeling with obvious higher model fitting- and cross-validation based adjusted R2 and lower RMSE. Meanwhile, the distribution map of PM2.5 concentration from PCA-GWR modeling also clearly depicts more spatial variation details in contrast to the one from regular GWR modeling. It can be concluded that the BSR enhanced PCA-GWR modeling could be a reliable way for effective air pollution concentration estimation in the coming future by involving all the potential predictor variables' contributions to PM2.5 variations.

  5. Calcium alpha-ketoglutarate administration to malnourished hemodialysis patients improves plasma arginine concentrations.

    Science.gov (United States)

    Riedel, E; Hampl, H; Steudle, V; Nündel, M

    1996-01-01

    Calcium alpha-ketoglutarate administration to 24 malnourished hemodialysis patients for 1 year leads to a significant increase in plasma concentrations of L-arginine from 53.6 +/- 18.3 (compared to a healthy control group: 87.5 +/- 27.3) to 71.1 +/- 15.9 mumol/l (p calcium alpha-ketoglutarate administration.

  6. Lithium-induced NDI: acetazolamide reduces polyuria but does not improve urine concentrating ability

    NARCIS (Netherlands)

    Groot, T. de; Doornebal, J.; Christensen, B.M.; Cockx, S.; Sinke, A.P.; Baumgarten, R.; Bedford, J.J.; Walker, R.J.; Wetzels, J.F.M.; Deen, P.M.T.

    2017-01-01

    Lithium is the mainstay treatment for patients with bipolar disorder, but it generally causes nephrogenic diabetes insipidus (NDI), a disorder in which the renal urine concentrating ability has become vasopressin insensitive. Li-NDI is caused by lithium uptake by collecting duct principal cells and

  7. Regulating NH4+, N0-, and K+ concentration and proportions improves in vitro tissue growth.

    Science.gov (United States)

    A mixture-amount experiment that simultaneously varied both the ratios and total ionic concentration (from 20-100 mM) of NH4+, NO3+, and K+ was used to maximize sweet orange callus growth cv. ‘Hamlin.’ These experiments were free of ion confounding effects, i.e. ions added via pH adjustments and sa...

  8. Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration

    CERN Document Server

    Moll, Michael; Lindström, G

    2000-01-01

    We present an investigation on the influence of the oxygen concentration on radiation-induced changes in the effective doping concentration of silicon detectors. Diodes fabricated from silicon with interstitial oxygen content ranging from below 2*10/sup 14/ to 9*10/sup 17/ cm/sup -3/ have been irradiated with fast neutrons up to a fluence of 2*10/sup 15/ cm/sup -2/. Our main interest focused on the so-called stable damage component in the change of the effective doping concentration being of prime importance for the application of silicon detectors in high-energy physics experiments. We demonstrate, that with a high oxygen enrichment the donor removal is appreciably reduced, reaching a value of only 10601130f the initial doping concentration for [O/sub i/]=9*10/sup 17/ cm/sup -3/, while for normal detector grade material with [O/sub i/] below 5*10/sup 16/ cm /sup -3/ that value is 60-90Furthermore, we show that the fluence proportional introduction of stable acceptors is independent of the oxygen concentratio...

  9. Improved sentinel node visualization in breast cancer by optimizing the colloid particle concentration and tracer dosage

    NARCIS (Netherlands)

    Valdés Olmos, R. A.; Tanis, P. J.; Hoefnagel, C. A.; Nieweg, O. E.; Muller, S. H.; Rutgers, E. J.; Kooi, M. L.; Kroon, B. B.

    2001-01-01

    Faint lymph uptake may hamper sentinel node (SN) identification by scintigraphy and subsequent gamma probe localization. The aim of the present study was to evaluate an adjustment in the colloid particle concentration and tracer dosage to optimize mammary lymphoscintigraphy. Scintigraphy was

  10. Improvement in the determination of elemental concentrations in PIXE analyses using artificial neural system

    International Nuclear Information System (INIS)

    Correa, R.; Dinator, M.I.; Morales, J.R.; Miranda, P.A.; Cancino, S.A.; Vila, I.; Requena, I.

    2008-01-01

    An Artificial Neural System, ANS, has been designed to operate in the analysis of spectra obtained from a PIXE (Proton Induced X-ray Emissions) application. The special designed ANS was used in the calculation of the concentrations of the major elements in the samples. Neural systems using several feed-forward ANN of similar topology working in parallel were trained with error back propagation algorithm using sets of spectra of known elemental concentrations. Following the training phase of the neural networks, other PIXE spectra were analyzed with this methodology providing unknown elemental concentrations. ANS results were compared with results obtained by traditional computer codes like AXIL and GUPIX, obtaining correlations factors close to one. The rather short time required to process each spectrum, of the order of microseconds, allows fast analysis of a large number of samples. Here we present applications of ANS in the PIXE analyses of samples of organic nature like liver, gills and muscle from fishes. ANS results were compared with elemental concentrations obtained in a previous application where a single ANN was used for each analyzed element. PIXE analyses were performed at the Nuclear Physics Laboratory of the University of Chile, using 2.2 MeV proton beams provided by a Van de Graaff accelerator. (author)

  11. An Improved Method of Predicting Extinction Coefficients for the Determination of Protein Concentration.

    Science.gov (United States)

    Hilario, Eric C; Stern, Alan; Wang, Charlie H; Vargas, Yenny W; Morgan, Charles J; Swartz, Trevor E; Patapoff, Thomas W

    2017-01-01

    Concentration determination is an important method of protein characterization required in the development of protein therapeutics. There are many known methods for determining the concentration of a protein solution, but the easiest to implement in a manufacturing setting is absorption spectroscopy in the ultraviolet region. For typical proteins composed of the standard amino acids, absorption at wavelengths near 280 nm is due to the three amino acid chromophores tryptophan, tyrosine, and phenylalanine in addition to a contribution from disulfide bonds. According to the Beer-Lambert law, absorbance is proportional to concentration and path length, with the proportionality constant being the extinction coefficient. Typically the extinction coefficient of proteins is experimentally determined by measuring a solution absorbance then experimentally determining the concentration, a measurement with some inherent variability depending on the method used. In this study, extinction coefficients were calculated based on the measured absorbance of model compounds of the four amino acid chromophores. These calculated values for an unfolded protein were then compared with an experimental concentration determination based on enzymatic digestion of proteins. The experimentally determined extinction coefficient for the native proteins was consistently found to be 1.05 times the calculated value for the unfolded proteins for a wide range of proteins with good accuracy and precision under well-controlled experimental conditions. The value of 1.05 times the calculated value was termed the predicted extinction coefficient. Statistical analysis shows that the differences between predicted and experimentally determined coefficients are scattered randomly, indicating no systematic bias between the values among the proteins measured. The predicted extinction coefficient was found to be accurate and not subject to the inherent variability of experimental methods. We propose the use of a

  12. Is improved lane keeping during cognitive load caused by increased physical arousal or gaze concentration toward the road center?

    Science.gov (United States)

    Li, Penghui; Markkula, Gustav; Li, Yibing; Merat, Natasha

    2018-08-01

    Driver distraction is one of the main causes of motor-vehicle accidents. However, the impact on traffic safety of tasks that impose cognitive (non-visual) distraction remains debated. One particularly intriguing finding is that cognitive load seems to improve lane keeping performance, most often quantified as reduced standard deviation of lateral position (SDLP). The main competing hypotheses, supported by current empirical evidence, suggest that cognitive load improves lane keeping via either increased physical arousal, or higher gaze concentration toward the road center, but views are mixed regarding if, and how, these possible mediators influence lane keeping performance. Hence, a simulator study was conducted, with participants driving on a straight city road section whilst completing a cognitive task at different levels of difficulty. In line with previous studies, cognitive load led to increased physical arousal, higher gaze concentration toward the road center, and higher levels of micro-steering activity, accompanied by improved lane keeping performance. More importantly, during the high cognitive task, both physical arousal and gaze concentration changed earlier in time than micro-steering activity, which in turn changed earlier than lane keeping performance. In addition, our results did not show a significant correlation between gaze concentration and physical arousal on the level of individual task recordings. Based on these findings, various multilevel models for micro-steering activity and lane keeping performance were conducted and compared, and the results suggest that all of the mechanisms proposed by existing hypotheses could be simultaneously involved. In other words, it is suggested that cognitive load leads to: (i) an increase in arousal, causing increased micro-steering activity, which in turn improves lane keeping performance, and (ii) an increase in gaze concentration, causing lane keeping improvement through both (a) further increased micro

  13. Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration

    International Nuclear Information System (INIS)

    Moll, M.; Fretwurst, E.; Lindstroem, G.

    2000-01-01

    We present an investigation on the influence of the oxygen concentration on radiation-induced changes in the effective doping concentration of silicon detectors. Diodes fabricated from silicon with interstitial oxygen content ranging from below 2x10 14 to 9x10 17 cm -3 have been irradiated with fast neutrons up to a fluence of 2x10 15 cm -2 . Our main interest focused on the so-called stable damage component in the change of the effective doping concentration being of prime importance for the application of silicon detectors in high-energy physics experiments. We demonstrate, that with a high oxygen enrichment the donor removal is appreciably reduced, reaching a value of only 10% of the initial doping concentration for [O i ]=9x10 17 cm -3 , while for normal detector grade material with [O i ] below 5x10 16 cm -3 that value is 60-90%. Furthermore, we show that the fluence proportional introduction of stable acceptors is independent of the oxygen concentration with an averaged introduction rate of (1.49±0.03)x10 -2 cm -1 . Only one material was found exhibiting a significantly smaller value of about 0.6x10 -2 cm -1 and thus indicating the possibility to suppress the radiation-induced acceptor creation by material modification. Finally, we show that the experimental findings disagree in several important aspects with predictions made by microscopic defect kinetics models, leaving the physical background of some of the measured data as an open question

  14. Modeling the distribution of colonial species to improve estimation of plankton concentration in ballast water

    Science.gov (United States)

    Rajakaruna, Harshana; VandenByllaardt, Julie; Kydd, Jocelyn; Bailey, Sarah

    2018-03-01

    The International Maritime Organization (IMO) has set limits on allowable plankton concentrations in ballast water discharge to minimize aquatic invasions globally. Previous guidance on ballast water sampling and compliance decision thresholds was based on the assumption that probability distributions of plankton are Poisson when spatially homogenous, or negative binomial when heterogeneous. We propose a hierarchical probability model, which incorporates distributions at the level of particles (i.e., discrete individuals plus colonies per unit volume) and also within particles (i.e., individuals per particle) to estimate the average plankton concentration in ballast water. We examined the performance of the models using data for plankton in the size class ≥ 10 μm and test ballast water compliance using the above models.

  15. Improving the monitoring of methanol concentration during high cell density fermentation of Pichia pastoris.

    Science.gov (United States)

    Ramon, R; Feliu, J X; Cos, O; Montesinos, J L; Berthet, F X; Valero, F

    2004-09-01

    The Pichia pastoris expression system is widely used for the production of recombinant proteins. A simple and efficient experimental set-up allowing on-line monitoring of the methanol concentration during the fermentation of P. pastoris based on the detection of the methanol vapor concentration in the exhaust air from fermenter by a tin dioxide (SnO2) semiconductor sensor is described. An experimental procedure to allow precise calibration of the system and to reduce methanol sensor's interferences (>95% reduction) are also presented and discussed. Accuracy and measurement error were estimated about 0.05 g x l(-1) and 6%, respectively. The efficient monitoring of methanol will help to advanced control of recombinant protein production and process optimization.

  16. Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed

    International Nuclear Information System (INIS)

    Grimm, J.W.; Lynch, J.A.

    2005-01-01

    Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most significant variables in both ammonium and nitrate models included: precipitation volume, the number of days since the last event, a measure of seasonality, latitude, and the proportion of land within 8 km covered by forest or devoted to industry and transportation. Additional variables included in the nitrate model were the proportion of land within 0.8 km covered by water and/or forest. Local and regional ammonia and nitrogen oxide emissions were not as well correlated as land cover. Modeled concentrations compared very well with event chemistry data collected at six NADP/AirMoN sites within the Chesapeake Bay Watershed. Wet deposition estimates were also consistent with observed deposition at selected sites. Accurately describing the spatial distribution of precipitation volume throughout the watershed is important in providing critical estimates of wet-fall deposition of ammonium and nitrate. - A linear least-squares regression approach was used to develop daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed

  17. Plyometric training improves voluntary activation and strength during isometric, concentric and eccentric contractions.

    Science.gov (United States)

    Behrens, Martin; Mau-Moeller, Anett; Mueller, Karoline; Heise, Sandra; Gube, Martin; Beuster, Nico; Herlyn, Philipp K E; Fischer, Dagmar-C; Bruhn, Sven

    2016-02-01

    This study investigated effects of plyometric training (6 weeks, 3 sessions/week) on maximum voluntary contraction (MVC) strength and neural activation of the knee extensors during isometric, concentric and eccentric contractions. Twenty-seven participants were randomly assigned to the intervention or control group. Maximum voluntary torques (MVT) during the different types of contraction were measured at 110° knee flexion (180°=full extension). The interpolated twitch technique was applied at the same knee joint angle during isometric, concentric and eccentric contractions to measure voluntary activation. In addition, normalized root mean square of the EMG signal at MVT was calculated. The twitch torque signal induced by electrical nerve stimulation at rest was used to evaluate training-related changes at the muscle level. In addition, jump height in countermovement jump was measured. After training, MVT increased by 20Nm (95% CI: 5-36Nm, P=0.012), 24Nm (95% CI: 9-40Nm, P=0.004) and 27Nm (95% CI: 7-48Nm, P=0.013) for isometric, concentric and eccentric MVCs compared to controls, respectively. The strength enhancements were associated with increases in voluntary activation during isometric, concentric and eccentric MVCs by 7.8% (95% CI: 1.8-13.9%, P=0.013), 7.0% (95% CI: 0.4-13.5%, P=0.039) and 8.6% (95% CI: 3.0-14.2%, P=0.005), respectively. Changes in the twitch torque signal of the resting muscle, induced by supramaximal electrical stimulation of the femoral nerve, were not observed, indicating no alterations at the muscle level, whereas jump height was increased. Given the fact that the training exercises consisted of eccentric muscle actions followed by concentric contractions, it is in particular relevant that the plyometric training increased MVC strength and neural activation of the quadriceps muscle regardless of the contraction mode. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  18. Optical, geometric and thermal study for solar parabolic concentrator efficiency improvement under Tunisia environment: A case study

    International Nuclear Information System (INIS)

    Skouri, Safa; Ben Salah, Mohieddine; Bouadila, Salwa; Balghouthi, Moncef; Ben Nasrallah, Sassi

    2013-01-01

    Highlights: • Design and construction of solar parabolic concentrator. • Photogrammetry study of SPC. • Slope error and optical efficiency of SPC. • Reflector materials of SPC. • Programmed tracking solar system. - Abstract: Renewable energy generation is becoming more prevalent today. It is relevant to consider that solar concentration technologies contribute to provide a real alternative to the consumption of fossil fuels. The purpose of this work is the characterization of a solar parabolic solar concentrator (SPC) designed, constructed and tested in the Research and Technologies Centre of Energy in Tunisia (CRTEn) in order to improve the performance of the system. Photogrammetry measurement used to analyze the slope errors and to determine hence determining the geometric deformation of the SPC system, which presents an average slope error around 0.0002 and 0.0073 mrad respectively in the center and in the extremities. An optimization of the most performed reflector material has been done by an experimental study of three types of reflectors. A two axes programmed tracking system realized, used and tested in this study. An experimental study is carried out to evaluate the solar parabolic concentrator thermal efficiency after the mechanical and the optical SPC optimization. The thermal energy efficiency varies from 40% to 77%, the concentrating system reaches an average concentration factor around 178

  19. Spherical cloaking using nonlinear transformations for improved segmentation into concentric isotropic coatings.

    Science.gov (United States)

    Qiu, Cheng-Wei; Hu, Li; Zhang, Baile; Wu, Bae-Ian; Johnson, Steven G; Joannopoulos, John D

    2009-08-03

    Two novel classes of spherical invisibility cloaks based on nonlinear transformation have been studied. The cloaking characteristics are presented by segmenting the nonlinear transformation based spherical cloak into concentric isotropic homogeneous coatings. Detailed investigations of the optimal discretization (e.g., thickness control of each layer, nonlinear factor, etc.) are presented for both linear and nonlinear spherical cloaks and their effects on invisibility performance are also discussed. The cloaking properties and our choice of optimal segmentation are verified by the numerical simulation of not only near-field electric-field distribution but also the far-field radar cross section (RCS).

  20. Highly concentrated EDTA gel improves cleaning efficiency of root canal preparation in vitro.

    Science.gov (United States)

    Putzer, P; Hoy, L; Günay, H

    2008-12-01

    Debris and smear layer, as a product of mechanical root canal instrumentation, reduce the effectiveness of pharmacological substances to prevent post-treatment diseases and impair direct contact of filling materials with a clean dentinal surface. The aim of this in vitro study was to investigate the presence and localization of debris and smear layer via scanning electron microscope analysis after standardized root canal preparation with different chelating agents. Dentin surfaces received treatment with: (1) 15% ethylenediaminetetraacetic acid (EDTA), (2) 18.6% EDTA (3) and 24% EDTA or without any demineralizing chemicals as control. Forty vertically split human premolars were sputtered and divided into coronal, middle, and apical sections, followed by a randomized, blinded score evaluation using five scores. Pairwise comparisons of all treatment groups against a control group have been performed by Mann-Whitney U test and the Kruskal-Wallis test. Debris grades showed no significant difference between the three regions of the root canals, except for 18.6% EDTA in the central third. Smear layer and smear plug removal was concentration-dependent. Removal of the smear layer in the three areas showed that there was a statistically significant difference between all parts when using 18.6% and 24% EDTA concentrations compared with the control. The best smear layer removal in the apical region was observed using a 24% EDTA gel as chelating agent and lubricant. The usage of EDTA gel >/=18.6% presented a better cleaning regime when compared to the control group.

  1. Improving optical performance of concentrator cells by means of a deposited nanopattern layer

    International Nuclear Information System (INIS)

    García-Linares, Pablo; Besson, Pierre; Weick, Clément; Baudrit, Mathieu; Dominguez, César; Dellea, Olivier; Kämpfe, Thomas; Jourlin, Yves

    2015-01-01

    Multijunction solar cells (MJSC) use anti-reflective coatings (ARC) to minimize Fresnel reflection losses for a family of light incidence angles. These coatings adapt the refractive index of the cell to that of the surrounding medium. Patterns with sizes in the range of the light wavelength can be used to further reduce reflections through diffraction. Transparent nanopatterns with a gradual profile, called moth-eye nanostructures, can adapt the refractive index of the optical interfaces (often with n∼1.5) used to encapsulate concentrator solar cells to that of the air (n air ∼1). Here we show the effect of a nanometric moth-eye ARC with a round motif deposited on commercial MJSC that achieves short-circuit current (I SC ) gains greater than 2% at normal incidence and even higher in the case of tilted illumination. In this work, MJSC with different moth-eye ARC are characterized under quantum efficiency (QE) as well as under concentrated illumination I-V in order to assess their potential. Simulations based on coupled wave analysis (RCWA) are used to fit the experimental results with successful results

  2. Dissolved oxygen concentration in the medium during cell culture: Defects and improvements.

    Science.gov (United States)

    Zhang, Kuan; Zhao, Tong; Huang, Xin; He, Yunlin; Zhou, Yanzhao; Wu, Liying; Wu, Kuiwu; Fan, Ming; Zhu, Lingling

    2016-03-01

    In vitro cell culture has provided a useful model to study the effects of oxygen on cellular behavior. However, it remains unknown whether the in vitro operations themselves affect the medium oxygen levels and the living states of cells. In addition, a prevailing controversy is whether reactive oxygen species (ROS) production is induced by continuous hypoxia or reoxygenation. In this study, we have measured the effects of different types of cell culture containers and the oxygen environment where medium replacement takes place on the actual oxygen tension in the medium. We found that the deviations of oxygen concentrations in the medium are much greater in 25-cm(2) flasks than in 24-well plates and 35-mm dishes. The dissolved oxygen concentrations in the medium were increased after medium replacement in normoxia, but remained unchanged in glove boxes in which the oxygen tension remained at a low level (11.4, 5.7, and 0.5% O2 ). We also found that medium replacement in normoxia increased the number of ROS-positive cells and reduced the cell viability; meanwhile, medium replacement in a glove box did not produce the above effects. Therefore, we conclude that the use of 25-cm(2) flasks should be avoided and demonstrate that continuous hypoxia does not produce ROS, whereas the reoxygenation that occurs during the harvesting of cells leads to ROS and induces cell death. © 2015 International Federation for Cell Biology.

  3. Injection of demineralized bone matrix with bone marrow concentrate improves healing in unicameral bone cyst.

    Science.gov (United States)

    Di Bella, Claudia; Dozza, Barbara; Frisoni, Tommaso; Cevolani, Luca; Donati, Davide

    2010-11-01

    Unicameral bone cysts are benign lesions that usually spontaneously regress with skeletal maturity; however, the high risk of pathologic fractures often justifies treatment that could reinforce a weakened bone cortex. Various treatments have been proposed but there is no consensus regarding the best procedure. We compared the healing rates and failures of two methods of cure based on multiple injections of corticosteroid or a single injection of demineralized bone matrix (DBM) in association with bone marrow concentrate (BMC). We retrospectively reviewed 184 patients who had one of the two treatments for unicameral bone cysts with cortical erosion. Clinical records were reviewed for treatment failures and radiographs for healing in all patients. The minimum followup was 12 months for the Steroids Group (mean, 48 months; range, 12-120 months) and 12 months for the DBM + BMC Group (mean, 20 months; range, 12-28 months). After one treatment we observed a lower healing rate of cysts treated with multiple injections of steroids compared with the healing after the first injection of DBM + BMC (21% versus 58%, respectively). At last followup, 38% healed with steroids and 71% with DBM + BMC. The rate of failure after one steroid injection was higher than after a single injection of BDM + BMC (63% versus 24%, respectively). We observed no difference in fracture rates after treatment between the two groups. A single injection of DBM added with autologous bone marrow concentrate appears to provide a higher healing rate with a lower number of failures compared with a single injection of steroids.

  4. Improving optical performance of concentrator cells by means of a deposited nanopattern layer

    Energy Technology Data Exchange (ETDEWEB)

    García-Linares, Pablo, E-mail: pablo.garcia-linares@cea.fr; Besson, Pierre; Weick, Clément; Baudrit, Mathieu [CEA-LITEN, Laboratoire de Photovoltaïque à Concentration, INES, Le Bourget du Lac (France); Dominguez, César [CEA-LITEN, Laboratoire de Photovoltaïque à Concentration, INES, Le Bourget du Lac (France); Instituto de Energía Solar - Universidad Politécnica de Madrid, Madrid (Spain); Dellea, Olivier [CEA-LITEN, Laboratoire de Surfaces Nanostructurées, Grenoble (France); Kämpfe, Thomas; Jourlin, Yves [Laboratoire Hubert Curien UMR CNRS, Université de Lyon, St. Etienne (France)

    2015-09-28

    Multijunction solar cells (MJSC) use anti-reflective coatings (ARC) to minimize Fresnel reflection losses for a family of light incidence angles. These coatings adapt the refractive index of the cell to that of the surrounding medium. Patterns with sizes in the range of the light wavelength can be used to further reduce reflections through diffraction. Transparent nanopatterns with a gradual profile, called moth-eye nanostructures, can adapt the refractive index of the optical interfaces (often with n∼1.5) used to encapsulate concentrator solar cells to that of the air (n{sub air}∼1). Here we show the effect of a nanometric moth-eye ARC with a round motif deposited on commercial MJSC that achieves short-circuit current (I{sub SC}) gains greater than 2% at normal incidence and even higher in the case of tilted illumination. In this work, MJSC with different moth-eye ARC are characterized under quantum efficiency (QE) as well as under concentrated illumination I-V in order to assess their potential. Simulations based on coupled wave analysis (RCWA) are used to fit the experimental results with successful results.

  5. Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed.

    Science.gov (United States)

    Grimm, J W; Lynch, J A

    2005-06-01

    Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most significant variables in both ammonium and nitrate models included: precipitation volume, the number of days since the last event, a measure of seasonality, latitude, and the proportion of land within 8km covered by forest or devoted to industry and transportation. Additional variables included in the nitrate model were the proportion of land within 0.8km covered by water and/or forest. Local and regional ammonia and nitrogen oxide emissions were not as well correlated as land cover. Modeled concentrations compared very well with event chemistry data collected at six NADP/AirMoN sites within the Chesapeake Bay Watershed. Wet deposition estimates were also consistent with observed deposition at selected sites. Accurately describing the spatial distribution of precipitation volume throughout the watershed is important in providing critical estimates of wet-fall deposition of ammonium and nitrate.

  6. The importance of the training-induced decrease in basal cortisol concentration in the improvement in muscular performance in humans.

    Science.gov (United States)

    Grandys, M; Majerczak, J; Kulpa, J; Duda, K; Rychlik, U; Zoladz, J A

    2016-01-01

    Acute exercise-induced changes in cortisol concentration (C) and training related adaptation within hypothalamic-pituitary-adrenal (HPA) axis has been widely examined, but their influence on muscle strength performance is at best uncertain. Twenty four young healthy men were randomly assigned to an endurance training group (ET, n=12) or to a non-exercising controls (CON, n=12). ET performed supervised endurance training on cycle ergometer for 20 weeks. Endurance training program improved exercise capacity (14 % increase in power output generated at peak oxygen uptake - VO(2peak)), muscle strength performance (increase in MVC - maximal voluntary contraction - by 9 % and in TTF 50 % MVC - time to fatigue at 50 % MVC - by 21 %) and led to a decrease in basal serum C concentration (P=0.006) and an increase in basal testosterone to cortisol (T/C) and free testosterone to cortisol (fT/C) ratios (P=0.01 and P=0.02, respectively). It was found that the decrease in C concentration (deltaC) was positively correlated to the increase in local muscular endurance (deltaTTF 50 % MVC). No significant hormonal changes were seen in CON group. It is concluded that greater decrease in cortisol concentration after the endurance training is accompanied by poorer improvement in skeletal muscle performance in previously untrained subjects.

  7. Zilpaterol improves feeding performance and fabrication yield of concentrate-finished cull cows.

    Science.gov (United States)

    Lawrence, T E; Gasch, C A; Hutcheson, J P; Hodgen, J M

    2011-07-01

    The objective of this study was to quantify the effects of zilpaterol hydrochloride (ZH) on feeding performance and fabrication yield of concentrate-finished cull cows. Three hundred twenty commercial cull cows (2 to 10 yr old) were obtained from ranches in Missouri and South Dakota and assigned to 1 of 2 treatments: 1) a control diet containing no ZH and 2) a diet that contained ZH. Cows were fed for 75, 88, or 110 d, and all received the control ration until ZH treatments were initiated. Twenty-four days before slaughter, ZH feeding began for the designated treatment pens; cows were fed ZH [8.33 mg/kg (100% DM basis)] for 20 d with a 4-d withdrawal period before slaughter. No differences (P>0.05) were detected between the 2 treatment groups for initial BW or DMI. Final BW (640.5 vs. 619.1 kg), ADG for the last 24 d (2.75 vs. 2.17 kg), and G:F for the last 24 d (0.160 vs. 0.126) were greater (P 0.05) were found for lean or skeletal maturity score, fat thickness, LM area, HCW, or calculated yield grade among the 2 treatment groups. Feeding ZH increased (P0.07) were found for the remaining fabrication yield attributes. The ZH-treated cows had greater (Pfeeding of ZH to concentrate-finished cull cows enhances production efficiencies and can add new value to the cull cow market. © 2011 American Society of Animal Science. All rights reserved.

  8. Consumption of a dietary portfolio of cholesterol lowering foods improves blood lipids without affecting concentrations of fat soluble compounds.

    Science.gov (United States)

    Ramprasath, Vanu R; Jenkins, David J A; Lamarche, Benoit; Kendall, Cyril W C; Faulkner, Dorothea; Cermakova, Luba; Couture, Patrick; Ireland, Chris; Abdulnour, Shahad; Patel, Darshna; Bashyam, Balachandran; Srichaikul, Korbua; de Souza, Russell J; Vidgen, Edward; Josse, Robert G; Leiter, Lawrence A; Connelly, Philip W; Frohlich, Jiri; Jones, Peter J H

    2014-10-18

    Consumption of a cholesterol lowering dietary portfolio including plant sterols (PS), viscous fibre, soy proteins and nuts for 6 months improves blood lipid profile. Plant sterols reduce blood cholesterol by inhibiting intestinal cholesterol absorption and concerns have been raised whether PS consumption reduces fat soluble vitamin absorption. The objective was to determine effects of consumption of a cholesterol lowering dietary portfolio on circulating concentrations of PS and fat soluble vitamins. Using a parallel design study, 351 hyperlipidemic participants from 4 centres across Canada were randomized to 1 of 3 groups. Participants followed dietary advice with control or portfolio diet. Participants on routine and intensive portfolio involved 2 and 7 clinic visits, respectively, over 6 months. No changes in plasma concentrations of α and γ tocopherol, lutein, lycopene and retinol, but decreased β-carotene concentrations were observed with intensive (week 12: p = 0.045; week 24: p = 0.039) and routine (week 12: p = 0.031; week 24: p = 0.078) portfolio groups compared to control. However, cholesterol adjusted β-carotene and fat soluble compound concentrations were not different compared to control. Plasma PS concentrations were increased with intensive (campesterol:p = 0.012; β-sitosterol:p = 0.035) and routine (campesterol: p = 0.034; β-sitosterol: p = 0.080) portfolio groups compared to control. Plasma cholesterol-adjusted campesterol and β-sitosterol concentrations were negatively correlated (p portfolio diet reduces serum total and LDL-C levels while increasing PS values, without altering fat soluble compounds concentrations. The extent of increments of PS with the current study are not deleterious and also maintaining optimum levels of fat soluble vitamins are of paramount necessity to maintain overall metabolism and health. Results indicate portfolio diet as one of the best options for CVD risk reduction

  9. [Improvement of sensitivity in the second generation HCV core antigen assay by a novel concentration method using polyethylene glycol (PEG)].

    Science.gov (United States)

    Higashimoto, Makiko; Takahashi, Masahiko; Jokyu, Ritsuko; Syundou, Hiromi; Saito, Hidetsugu

    2007-11-01

    A HCV core antigen (Ag) detection assay system, Lumipulse Ortho HCV Ag has been developed and is commercially available in Japan with a lower detection level limit of 50 fmol/l, which is equivalent to 20 KIU/ml in PCR quantitative assay. HCV core Ag assay has an advantage of broader dynamic range compared with PCR assay, however the sensitivity is lower than PCR. We developed a novel HCV core Ag concentration method using polyethylene glycol (PEG), which can improve the sensitivity five times better than the original assay. The reproducibility was examined by consecutive five-time measurement of HCV patients serum, in which the results of HCV core Ag original and concentrated method were 56.8 +/- 8.1 fmol/l (mean +/- SD), CV 14.2% and 322.9 +/- 45.5 fmol/l CV 14.0%, respectively. The assay results of HCV negative samples in original HCV core Ag were all 0.1 fmol/l and the results were same even in the concentration method. The results of concentration method were 5.7 times higher than original assay, which was almost equal to theoretical rate as expected. The assay results of serially diluted samples were also as same as expected data in both original and concentration assay. We confirmed that the sensitivity of HCV core Ag concentration method had almost as same sensitivity as PCR high range assay in the competitive assay study using the serially monitored samples of five HCV patients during interferon therapy. A novel concentration method using PEG in HCV core Ag assay system seems to be useful for assessing and monitoring interferon treatment for HCV.

  10. Predicting phosphorus concentrations in British rivers resulting from the introduction of improved phosphorus removal from sewage effluent

    International Nuclear Information System (INIS)

    Bowes, Michael J.; Neal, Colin; Jarvie, Helen P.; Smith, Jim T.; Davies, Helen N.

    2010-01-01

    Phosphorus (P) concentration and flow data gathered during the 1990s for a range of British rivers were used to determine the relative contributions of point and diffuse inputs to the total P load, using the Load Apportionment Model (LAM). Heavily urbanised catchments were dominated by sewage inputs, but the majority of the study catchments received most of their annual phosphorus load from diffuse sources. Despite this, almost 80% of the study sites were dominated by point source inputs for the majority of the year, particularly during summer periods when eutrophication risk is greatest. This highlights the need to reduce sewage P inputs to improve the ecological status of British rivers. These modelled source apportionment estimates were validated against land-use data and boron load (a chemical marker for sewage). The LAM was applied to river flow data in subsequent years, to give predicted P concentrations (assuming no change in P source inputs), and these estimates were compared with observed concentration data. This showed that there had been significant reductions in P concentration in the River Thames, Aire and Ouse in the period 1999 to 2002, which were attributable to the introduction of P stripping at sewage treatment works (STW). The model was then used to forecast P concentrations resulting from the introduction of P removal at STW to a 2 or 1 mg l -1 consent limit. For the urbanised rivers in this study, the introduction of phosphorus stripping to a 1 mg l -1 consent level at all STW in the catchment would not reduce P concentrations in the rivers to potentially limiting concentrations. Therefore, further sewage P stripping will be required to comply with the Water Framework Directive. Diffuse P inputs may also need to be reduced before some of the highly nutrient-enriched rivers achieve good ecological status.

  11. Improvement of mammalian cell culture performance through surfactant enabled concentrated feed media.

    Science.gov (United States)

    Hossler, Patrick; McDermott, Sean; Racicot, Christopher; Fann, John C H

    2013-01-01

    The design of basal and feed media in mammalian cell culture is paramount towards ensuring acceptable upstream process performance in various operation modes, especially fed-batch culture. Mammalian cell culture media designs have evolved from the classical formulations designed by Eagle and Ham, to today's formulations designed from continuous improvement and statistical frameworks. Feed media is especially important for ensuring robust cell growth, productivity, and ensuring the product quality of recombinant therapeutics are within acceptable ranges. Numerous studies have highlighted the benefit of various media designs, supplements, and feed addition strategies towards the resulting cell culture process. In this work we highlight the use of a top-down level approach towards feed media design enabled by the use of select surfactants for the targeted enrichment of a chemically defined feed media. The use of the enriched media was able to improve product titers at g/L levels, without adversely impacting the growth of multiple Chinese Hamster Ovary cell lines or the product quality of multiple recombinant antibodies. © 2013 American Institute of Chemical Engineers.

  12. Improvement in mechanical properties of high concentration particle doped thermoset composites

    International Nuclear Information System (INIS)

    Ahmed, N.

    2009-01-01

    The paper relates to high concentration particle doped composites based on thermosetting polymer systems in which the sequential addition of particles of certain size distribution is followed by curing and casting of the slurry to form a thermoset composite. Conventionally, at a threshold of beyond 90% of particles by weight of the polymer using triglyceride, the mechanical properties of the composite exhibit a sharp decline. The present research mitigates this behavior by incorporating a unique combination of cross-linking agents in the base polymer to impart exceptional mechanical properties to the composite. More specifically, the base polymer consists of butadiene, with triglyceride as cross-linking agent together with hydroxy-alkane as the chain extension precursors, when tune to the appropriate level of hard segment ratio in the polymer. An added advantage according to the present work resides in the analytical nature of butadiene pre-polymer as opposed to natural product; traditional composites based on natural sources are hampered by their inconsistent chemical composition and poor shelf life in the fabricated composite. The thermoset composite according the present research exhibits superior tensile strength (200-300 psi) properties using particle loading as high as 92% by weight of the fabricated composite as measured on a Tinius Olsen machine. Dynamic Mechanical Testing reveals interesting combination of storage and loss moduli in the fabricated specimens as a function of optimizing the thermal response of the viscoelastic composite to imposed vibration loading. (author)

  13. Selectivity improvement of positive photoionization ion mobility spectrometry for rapid detection of organophosphorus pesticides by switching dopant concentration.

    Science.gov (United States)

    Zhou, Qinghua; Li, Jia; Wang, Bin; Wang, Shuang; Li, Haiyang; Chen, Jinyuan

    2018-01-01

    Ion mobility spectrometry (IMS) opened a potential avenue for the rapid detection of organophosphorus pesticides (OPPs), though an improved selectivity of stand-alone IMS was still in high demand. In this study, a stand-alone positive photoionization ion mobility spectrometry (PP-IMS) apparatus was constructed for the rapid detection of OPPs with acetone as dopant. The photoionization of acetone molecules was induced by the ultraviolet irradiation to produce the reactant ions (Ac) 2 H + , which were employed to ionize the OPPs including fenthion, imidan, phosphamidon, dursban, dimethoate and isocarbophos via the proton transfer reaction. Due to the difference in proton affinity, the tested OPPs exhibited the different dopant-dependent manners. Based on this observation, the switching of dopant concentration was implemented to improve the selectivity of PP-IMS for OPPs detection. For instance, a mixture of fenthion, dursban and dimethoate was tested. By switching the concentration of doped acetone from 0.07 to 2.33 to 19.94mgL -1 , the ion peaks of fenthion and dursban were inhibited in succession, achieving the selective detection of dimethoate at last. In addition, another mixture of imidan and phosphamidon was initially detected by PP-IMS with a dose of 0.07mgL -1 acetone, indicating that their ion peaks were severely overlapped; when the concentration of doped acetone was switched to 19.94mgL -1 , the inhibition of imidan signals promised the accurate identification of phosphamidon in mixture. Finally, the PP-IMS in combination of switching dopant concentration was applied to detect the mixed fenthion, dursban and dimethoate in Chinese cabbage, demonstrating the applicability of proposed method to real samples. Copyright © 2017. Published by Elsevier B.V.

  14. Sensor integration of multiple tripolar concentric ring electrodes improves pentylenetetrazole-induced seizure onset detection in rats.

    Science.gov (United States)

    Makeyev, Oleksandr; Ding, Quan; Kay, Steven M; Besio, Walter G

    2012-01-01

    As epilepsy affects approximately one percent of the world population, electrical stimulation of the brain has recently shown potential for additive seizure control therapy. Previously, we applied noninvasive transcranial focal stimulation via tripolar concentric ring electrodes on the scalp of rats after inducing seizures with pentylenetetrazole. We developed a system to detect seizures and automatically trigger the stimulation and evaluated the system on the electrographic activity from rats. In this preliminary study we propose and validate a novel seizure onset detection algorithm based on exponentially embedded family. Unlike the previously proposed approach it integrates the data from multiple electrodes allowing an improvement of the detector performance.

  15. A Novel Concentrator Photovoltaic (CPV System with the Improvement of Irradiance Uniformity and the Capturing of Diffuse Solar Radiation

    Directory of Open Access Journals (Sweden)

    Nguyen Xuan Tien

    2016-09-01

    Full Text Available This paper proposes a novel concentrator photovoltaic (CPV system with improved irradiation uniformity and system efficiency. CPV technology is very promising its for highly efficient solar energy conversion. A conventional CPV system usually uses only one optical component, such as a refractive Fresnel lens or a reflective parabolic dish, to collect and concentrate solar radiation on the solar cell surface. Such a system creates strongly non-uniform irradiation distribution on the solar cell, which tends to cause hot spots, current mismatch, and degrades the overall efficiency of the system. Additionally, a high-concentration CPV system is unable to collect diffuse solar radiation. In this paper, we propose a novel CPV system with improved irradiation uniformity and collection of diffuse solar radiation. The proposed system uses a Fresnel lens as a primary optical element (POE to concentrate and focus the sunlight and a plano-concave lens as a secondary optical element (SOE to uniformly distribute the sunlight over the surface of multi-junction (MJ solar cells. By using the SOE, the irradiance uniformity is significantly improved in the system. Additionally, the proposed system also captures diffuse solar radiation by using an additional low-cost solar cell surrounding MJ cells. In our system, incident direct solar radiation is captured by MJ solar cells, whereas incident diffuse solar radiation is captured by the low-cost solar cell. Simulation models were developed using a commercial optical simulation tool (LightTools™. The irradiance uniformity and efficiency of the proposed CPV system were analyzed, evaluated, and compared with those of conventional CPV systems. The analyzed and simulated results show that the CPV system significantly improves the irradiance uniformity as well as the system efficiency compared to the conventional CPV systems. Numerically, for our simulation models, the designed CPV with the SOE and low-cost cell provided

  16. Optimization of Concentration and EM4 Augmentation for Improving Bio-Gas Productivity from Jatropha curcas Linn Capsule Husk

    Directory of Open Access Journals (Sweden)

    Praptiningsih G.A

    2014-02-01

    Full Text Available Most literature suggests that two-phase digestion is more efficient than single-phase. The series of two-phase digestion studies have been conducted from 2011 to 2013 at the research farm of PT Bumimas Ekapersada, West Java, Indonesia. This paper reports on a research on optimation of concentration and augmentation of EM-4 (effective microorganism-4, a local commercial decomposer, as efforts to stabilize a biogas technology which made ​​from husk capsules of Jatropha curcas Linn (DH-JcL. The studies of increasing organic loading rate (OLR for the two-phase digestion was conducted to improve efficiency.  The concentration variable studied was 1: 8 (1 part DH-JCL and 8 parts water, compared to 1: 12 as a control. The augmentation treatment is the addition of EM-4 by 5% (v/v. It was also examined the augmentation of F2-EM4 (150 times duplication of EM-4 due to cost consideration. The studies were conducted in the laboratory which using a liter and two liters of glass digester and glass wool as immobilized growth. The results of this study support the previous studies: the optimum concentration was 1: 8, EM-4 was able to increase biogas production in two-phase digestion, yet biogas production decrease at single-phase. F2-EM4’s ability to support production of biogas were equivalent to that of EM-4.

  17. Improved optical properties and detectivity of an uncooled silicon carbide mid-wave infrared optical detector with increased dopant concentration

    International Nuclear Information System (INIS)

    Lim, Geunsik; Kar, Aravinda; Manzur, Tariq

    2012-01-01

    An n-type 4H-SiC substrate is doped with gallium using a laser doping technique and its optical response is investigated at the mid-wave infrared (MWIR) wavelength 4.21 μm as a function of the dopant concentration. The dopant creates a p-type energy level of 0.3 eV, which is the energy of a photon corresponding to the MWIR wavelength 4.21 μm. Therefore, Ga-doped SiC can be used as an uncooled MWIR detector because an optical signal was obtained at this wavelength when the sample was at room temperature. The energy level of the Ga dopant in the substrate was confirmed by optical absorption spectroscopy. Secondary ion mass spectroscopy (SIMS) of the doped samples revealed an enhancement in the solid solubility of Ga in the substrate when doping is carried out by increasing the number of laser scans. A higher dopant concentration increases the number of holes in the dopant energy level, enabling photoexcitation of more electrons from the valence band by the incident MWIR photons. The detector performance improves as the dopant concentration increases from 1.15 × 10 19 to 6.25 × 10 20 cm −3 . The detectivity of the optical photodetector is found to be 1.07 × 10 10 cm Hz 1/2 W −1 for the case of doping with four laser passes. (paper)

  18. Improvement in grade of minerals using simultaneous Bio-oxidation of invisible gold concentrate and deep-sea manganese crust

    Science.gov (United States)

    Myung, EunJi; Cho, Kang Hee; Kim, Hyun Soo; Park, Cheon Young

    2016-04-01

    Many sulfides of metal such as galena, sphalerite, chalcopyrite, and pyrite, are semiconductors. When two kinds of such minerals contact each other in an electrolyte, a galvanic couple, where the mineral of lower rest potential as anode, and that of higher rest potential as cathode forms. Manganese dioxide is also a semiconductor with much higher rest potential than all sulfides mentioned above, so that a galvanic couple in which both the minerals would dissolve simultaneously can form, when it contacts with any of the sulfides. The aim of this study was to investigate the improvement in grade of minerals using the simultaneous bio-oxidation of deep-sea manganese crust and invisible gold concentrate. The samples(deep-sea manganese crust and invisible gold concentrate) were characterized by chemical and XRD analysis. The primary components of the invisible gold concentrate was pyrite and quartz and the deep-sea manganese crust was amorphous material, as detected using XRD. The result of chemical analysis showed that Au, Ag, Te contents in the invisible gold concentrate 130.2, 954.1 and 1,043.6 mg/kg, respectively. and that Mn, Ni, Co contents in the deep-sea manganese crust 19,501.5, 151.9, 400.4 mg/kg, respectively. In order to increase the bacteria's tolerance of heavy metals, the bacteria using bio-oxidation experiments were repeatedly subcultured in an Cu adaptation-medium containing of 382.98 mg/l for 20 periods of 21 days. The improvement in grade of samples of in present adapted bacteria condition was greater than another conditions(control and in present non-adapted bacteria). The Au-Ag-Te contents in the invisible gold concentrate was enhanced in the order of physical oxidation, simultaneous/non-adaptive bio-oxidation, adaptive/bio-oxidation, simultaneous/adaptive bio-oxidation. If the bacteria is adapted to heavy metal ions and an optimization of conditions is found in future bio-oxidation-leaching processes. Acknowledgment : "This research was supported

  19. Visual feedback attenuates mean concentric barbell velocity loss, and improves motivation, competitiveness, and perceived workload in male adolescent athletes.

    Science.gov (United States)

    Weakley, Jonathon Js; Wilson, Kyle M; Till, Kevin; Read, Dale B; Darrall-Jones, Joshua; Roe, Gregory; Phibbs, Padraic J; Jones, Ben

    2017-07-12

    It is unknown whether instantaneous visual feedback of resistance training outcomes can enhance barbell velocity in younger athletes. Therefore, the purpose of this study was to quantify the effects of visual feedback on mean concentric barbell velocity in the back squat, and to identify changes in motivation, competitiveness, and perceived workload. In a randomised-crossover design (Feedback vs. Control) feedback of mean concentric barbell velocity was or was not provided throughout a set of 10 repetitions in the barbell back squat. Magnitude-based inferences were used to assess changes between conditions, with almost certainly greater differences in mean concentric velocity between the Feedback (0.70 ±0.04 m·s) and Control (0.65 ±0.05 m·s) observed. Additionally, individual repetition mean concentric velocity ranged from possibly (repetition number two: 0.79 ±0.04 vs. 0.78 ±0.04 m·s) to almost certainly (repetition number 10: 0.58 ±0.05 vs. 0.49 ±0.05 m·s) greater when provided feedback, while almost certain differences were observed in motivation, competitiveness, and perceived workload, respectively. Providing adolescent male athletes with visual kinematic information while completing resistance training is beneficial for the maintenance of barbell velocity during a training set, potentially enhancing physical performance. Moreover, these improvements were observed alongside increases in motivation, competitiveness and perceived workload providing insight into the underlying mechanisms responsible for the performance gains observed. Given the observed maintenance of barbell velocity during a training set, practitioners can use this technique to manipulate training outcomes during resistance training.

  20. Improvements in concentration, working memory and sustained attention following consumption of a natural citicoline-caffeine beverage.

    Science.gov (United States)

    Bruce, Steven E; Werner, Kimberly B; Preston, Brittany F; Baker, Laurie M

    2014-12-01

    This study examined the neurocognitive and electrophysiological effects of a citicoline-caffeine-based beverage in 60 healthy adult participants enrolled in a randomized, double-blind, placebo-controlled trial. Measures of electrical brain activity using electroencephalogram (EEG) and neuropsychological measures examining attention, concentration and reaction time were administered. Compared to placebo, participants receiving the citicoline-caffeine beverage exhibited significantly faster maze learning times and reaction times on a continuous performance test, fewer errors in a go/no-go task and better accuracy on a measure of information processing speed. EEG results examining P450 event-related potentials revealed that participants receiving the citicoline-caffeine beverage exhibited higher P450 amplitudes than controls, suggesting an increase in sustained attention. Overall, these findings suggest that the beverage significantly improved sustained attention, cognitive effort and reaction times in healthy adults. Evidence of improved P450 amplitude indicates a general improvement in the ability to accommodate new and relevant information within working memory and overall enhanced brain activation.

  1. Improved concentration and separation of particles in a 3D dielectrophoretic chip integrating focusing, aligning and trapping

    KAUST Repository

    Li, Ming

    2012-10-18

    This article presents a dielectrophoresis (DEP)-based microfluidic device with the three-dimensional (3D) microelectrode configuration for concentrating and separating particles in a continuous throughflow. The 3D electrode structure, where microelectrode array are patterned on both the top and bottom surfaces of the microchannel, is composed of three units: focusing, aligning and trapping. As particles flowing through the microfluidic channel, they are firstly focused and aligned by the funnel-shaped and parallel electrode array, respectively, before being captured at the trapping unit due to negative DEP force. For a mixture of two particle populations of different sizes or dielectric properties, with a careful selection of suspending medium and applied field, the population exhibits stronger negative DEP manipulated by the microelectrode array and, therefore, separated from the other population which is easily carried away toward the outlet due to hydrodynamic force. The functionality of the proposed microdevice was verified by concentrating different-sized polystyrene (PS) microparticles and yeast cells dynamically flowing in the microchannel. Moreover, separation based on size and dielectric properties was achieved by sorting PS microparticles, and isolating 5 μm PS particles from yeast cells, respectively. The performance of the proposed micro-concentrator and separator was also studied, including the threshold voltage at which particles begin to be trapped, variation of cell-trapping efficiency with respect to the applied voltage and flow rate, and the efficiency of separation experiments. The proposed microdevice has various advantages, including multi-functionality, improved manipulation efficiency and throughput, easy fabrication and operation, etc., which shows a great potential for biological, chemical and medical applications. © 2012 Springer-Verlag Berlin Heidelberg.

  2. The use of different concentrations of ginger root oil to improve the mating propensity of the Medfly sterile males

    International Nuclear Information System (INIS)

    Fadhl, Salma; Msaad Guerfali, M.; Kahlani, A.; Hamden, Haithem; Chevrier, C.

    2008-01-01

    The sterile insect technique in an efficient technique used to control fruit flies such as Medfly Ceratitis Capitata (Wiedemann) (Diptera : Tephritidae). Unfortunately, this technique involves mass breeding of huge quantities of target insects in the factory and sterilizing the males by exposing them to low doses of radiation. this procedure reduces the mating propensity of the sterile males which are the active agent of the technique. It was reported that the exposition of the sterile males to ginger root oil (Zingiber official Roscoe (Zingiberaceae)) improves the mating propensity of the sterile males in comparison with the non exposed ones. In this study, we exposed irradiated males at two different doses (100 and 110 Gy) to different concentrations of the ginger oil (20μl; 50μl; 80μl; 0.25 ml;0.5 ml; 1 ml) the third day after emergence. This study shows that the irradiated males at 100 Gy are more competitive in comparison with those irradiated at 110 Gy with a mating propensity percentage respectively of 60 and 35 %. regarding the exposition dose of the ginger oil, 1 ml gave the best mating propensity ( 42%) in comparison with the other concentrations

  3. Low concentrations of Rhodamine-6G selectively destroy tumor cells and improve survival of melanoma transplanted mice.

    Science.gov (United States)

    Kutushov, M; Gorelik, O

    2013-01-01

    Rhodamine-6G is a fluorescent dye binding to mitochondria, thus reducing the intact mitochondria number and inhibiting mitochondrial metabolic activity. Resultantly, the respiratory chain functioning becomes blocked, the cell "suffocated" and eventually destroyed. Unlike normal cells, malignant cells demonstrate a priori reduced mitochondrial numbers and aberrant metabolism. Therefore, a turning point might exist, when Rhodamine-induced loss of active mitochondria would selectively destroy malignant, but spare normal cells. Various malignant vs. non-malignant cell lines were cultured with Rhodamine-6G at different concentrations. In addition, C57Bl mice were implanted with B16-F10 melanoma and treated with Rhodamine-6G at different dosage/time regimens. Viability and proliferation of cultured tumor cells were time and dose-dependently inhibited, up to 90%, by Rhodamine-6G, with profound histological signs of cell death. By contrast, inhibition of normal control cell proliferation hardly exceeded 15-17%. Melanoma-transplanted mice receiving Rhodamine-6G demonstrated prolonged survival, improved clinical parameters, inhibited tumor growth and metastases count, compared to their untreated counterparts. Twice-a-week 10-6M Rhodamine-6G regimen yielded the most prominent results. We conclude that malignant, but not normal, cells are selectively destroyed by low doses of Rhodamine-6G. In vivo, such treatment selectively suppresses tumor progression and dissemination, thus improving prognosis. We suggest that selective anti-tumor properties of Rhodamine-6G are based on unique physiologic differences in energy metabolism between malignant and normal cells. If found clinically relevant, low concentrations of Rhodamine-6G might be useful for replacing, or backing up, more aggressive nonselective chemotherapeutic compounds.

  4. Improved methylene blue two-phase titration method for determining cationic surfactant concentration in high-salinity brine.

    Science.gov (United States)

    Cui, Leyu; Puerto, Maura; López-Salinas, José L; Biswal, Sibani L; Hirasaki, George J

    2014-11-18

    The methylene blue (MB) two-phase titration method is a rapid and efficient method for determining the concentrations of anionic surfactants. The point at which the aqueous and chloroform phases appear equally blue is called Epton's end point. However, many inorganic anions, e.g., Cl(-), NO3(-), Br(-), and I(-), can form ion pairs with MB(+) and interfere with Epton's end point, resulting in the failure of the MB two-phase titration in high-salinity brine. Here we present a method to extend the MB two-phase titration method for determining the concentration of various cationic surfactants in both deionized water and high-salinity brine (22% total dissolved solid). A colorless end point, at which the blue color is completely transferred from the aqueous phase to the chloroform phase, is proposed as titration end point. Light absorbance at the characteristic wavelength of MB is measured using a spectrophotometer. When the absorbance falls below a threshold value of 0.04, the aqueous phase is considered colorless, indicating that the end point has been reached. By using this improved method, the overall error for the titration of a permanent cationic surfactant, e.g., dodecyltrimethylammonium bromide, in deionized (DI) water and high-salinity brine is 1.274% and 1.322% with limits of detection (LOD) of 0.149 and 0.215 mM, respectively. Compared to the traditional acid-base titration method, the error of this improved method for a switchable cationic surfactant, e.g., tertiary amine surfactant (Ethomeen C12), is 2.22% in DI water and 0.106% with LOD of 0.369 and 0.439 mM, respectively.

  5. An optimized metal grid design to improve the solar cell performance under solar concentration using multiobjective computation

    International Nuclear Information System (INIS)

    Djeffal, F.; Bendib, T.; Arar, D.; Dibi, Z.

    2013-01-01

    Highlights: ► A new MOGA-based approach to design the solar cell metal grid is proposed. ► The cell parameters have been ascertained including the high illumination effects. ► An improved electrical behavior of the solar cell is found. ► The proposed optimized metal grid design is suitable for photovoltaic applications. -- Abstract: In this paper, a new multiobjective genetic algorithm (MOGA)-based approach is proposed to optimize the metal grid design in order to improve the electrical performance and the conversion efficiency behavior of the solar cells under high intensities of illumination. The proposed approach is applied to investigate the effect of two different metal grid patterns (one with 2 busbars outside the active area (linear grid) and another one with a circular busbar surrounding the active area (circular grid)) on the electrical performance of high efficiency c-Si solar cells under concentrated light (up to 150 suns). The dimensional and electrical parameters of the solar cell have been ascertained, and analytical expressions of the power losses and conversion efficiency, including high illumination effects, have been presented. The presented analytical models are used to formulate different objective functions, which are the prerequisite of the multiobjective optimization. The optimized design can also be incorporated into photovoltaic circuit simulator to study the impact of our approach on the photovoltaic circuit design

  6. Improvement of physicochemical and rheological properties of kombucha fermented milk products by addition of transglutaminase and whey protein concentrate

    Directory of Open Access Journals (Sweden)

    Iličić Mirela D.

    2016-01-01

    Full Text Available The objective of this work was to investigate the effect of addition of transglutaminase (TG-0.02%, w/w and whey protein concentrate (WPC-0.03%, w/w, on quality of kombucha fermented milk product. Samples were prepared from pasteurized semi-skim milk (0.9%, w/w fat and kombucha inoculum (10%, v/v. The pH values were measured during the fermentation of milk (lasted until reached 4.5. Syneresis, water holding capacity and the product texture (firmness and consistency, were assessed after production. Rheological properties of kombucha fermented milk samples were measured during ten days of storage. The sample containing TG had the lowest syneresis (21 ml, the highest water holding capacity (62% and the highest textural characteristics (firmness - 23.99g, consistency - 626.54gs after production. The addition of WPC to milk improved the rheological properties, while the addition of TG improved it even to a significantly greater extent after the production and during 10 days of the storage. [Projekat Ministarstva nauke Republike Srbije, br. 46009

  7. Improvement of Gold Leaching from a Refractory Gold Concentrate Calcine by Separate Pretreatment of Coarse and Fine Size Fractions

    Directory of Open Access Journals (Sweden)

    Qian Li

    2017-05-01

    Full Text Available A total gold extraction of 70.2% could only be reached via direct cyanidation from a refractory As-, S- and C-bearing gold concentrate calcine, and the gold extraction varied noticeably with different size fractions. The reasons for unsatisfactory gold extraction from the calcine were studied through analyses of chemical composition, chemical phase and SEM-EDS of different sizes of particles. It was found that a significant segregation of compositions occurred during the grinding of gold ore before flotation. As a result, for the calcine obtained after oxidative roasting, the encapsulation of gold by iron oxides was easily engendered in finer particles, whilst in coarser particles the gold encapsulation by silicates was inclined to occur likely due to melted silicates blocking the porosity of particles. The improvement of gold leaching from different size fractions was further investigated through pretreatments with alkali washing, acid pickling or sulfuric acid curing-water leaching. Finally, a novel process was recommended and the total gold extraction from the calcine could be increased substantially to 93.6% by the purposeful pretreatment with alkali washing for the relatively coarse size fraction (+37 μm and sulfuric acid curing–water leaching for the fine size fraction (−37 μm.

  8. Improvement on the concentrated grape juice physico-chemical characteristics by an enzymatic treatment and Membrane Separation Processes

    Directory of Open Access Journals (Sweden)

    PLÍNIO R.F. CAMPOS

    2016-03-01

    Full Text Available ABSTRACT In this work, the improvement on the concentrated grape juice physico-chemical characteristics by using an enzymatic treatment followed by Membrane Separation Process (MSP has been investigated. By using Novozym 33095(r and Ultrazym AFP L(r enzymes varying three operating parameters, the best result on the grape pulp characteristics was attained for the Novozym 33095(r performed at 35oC, 15 min. and 50 mgL-1. In micro/ultra filtration processes after enzymatic pretreatment, the best performance of the MSP with high permeate flux value and suitable grape juice characteristics was attained using 0.05 mm membrane pore size, 1 bar pressure and 40 oC treatment temperature. When reverse osmosis process is operated at 40 bar and 40oC, high soluble solid and low turbidity values are attained. An enzymatic treatment along with MSP has shown an alternative and efficient grape juice processing system, being possible to extend to other foods.

  9. Ablation of neurons expressing melanin-concentrating hormone (MCH) in adult mice improves glucose tolerance independent of MCH signaling.

    Science.gov (United States)

    Whiddon, Benjamin B; Palmiter, Richard D

    2013-01-30

    Melanin-concentrating hormone (MCH)-expressing neurons have been ascribed many roles based on studies of MCH-deficient mice. However, MCH neurons express other neurotransmitters, including GABA, nesfatin, and cocaine-amphetamine-regulated transcript. The importance of these other signaling molecules made by MCH neurons remains incompletely characterized. To determine the roles of MCH neurons in vivo, we targeted expression of the human diphtheria toxin receptor (DTR) to the gene for MCH (Pmch). Within 2 weeks of diphtheria toxin injection, heterozygous Pmch(DTR/+) mice lost 98% of their MCH neurons. These mice became lean but ate normally and were hyperactive, especially during a fast. They also responded abnormally to psychostimulants. For these phenotypes, ablation of MCH neurons recapitulated knock-out of MCH, so MCH appears to be the critical neuromodulator released by these neurons. In contrast, MCH-neuron-ablated mice showed improved glucose tolerance when compared with MCH-deficient mutant mice and wild-type mice. We conclude that MCH neurons regulate glucose tolerance through signaling molecules other than MCH.

  10. Improved predictive mapping of indoor radon concentrations using ensemble regression trees based on automatic clustering of geological units

    International Nuclear Information System (INIS)

    Kropat, Georg; Bochud, Francois; Jaboyedoff, Michel; Laedermann, Jean-Pascal; Murith, Christophe; Palacios, Martha; Baechler, Sébastien

    2015-01-01

    Purpose: According to estimations around 230 people die as a result of radon exposure in Switzerland. This public health concern makes reliable indoor radon prediction and mapping methods necessary in order to improve risk communication to the public. The aim of this study was to develop an automated method to classify lithological units according to their radon characteristics and to develop mapping and predictive tools in order to improve local radon prediction. Method: About 240 000 indoor radon concentration (IRC) measurements in about 150 000 buildings were available for our analysis. The automated classification of lithological units was based on k-medoids clustering via pair-wise Kolmogorov distances between IRC distributions of lithological units. For IRC mapping and prediction we used random forests and Bayesian additive regression trees (BART). Results: The automated classification groups lithological units well in terms of their IRC characteristics. Especially the IRC differences in metamorphic rocks like gneiss are well revealed by this method. The maps produced by random forests soundly represent the regional difference of IRCs in Switzerland and improve the spatial detail compared to existing approaches. We could explain 33% of the variations in IRC data with random forests. Additionally, the influence of a variable evaluated by random forests shows that building characteristics are less important predictors for IRCs than spatial/geological influences. BART could explain 29% of IRC variability and produced maps that indicate the prediction uncertainty. Conclusion: Ensemble regression trees are a powerful tool to model and understand the multidimensional influences on IRCs. Automatic clustering of lithological units complements this method by facilitating the interpretation of radon properties of rock types. This study provides an important element for radon risk communication. Future approaches should consider taking into account further variables

  11. Acetylcysteine reduces plasma homocysteine concentration and improves pulse pressure and endothelial function in patients with end-stage renal failure

    DEFF Research Database (Denmark)

    Scholze, Alexandra; Rinder, Christiane; Beige, Joachim

    2004-01-01

    Increased oxidative stress, elevated plasma homocysteine concentration, increased pulse pressure, and impaired endothelial function constitute risk factors for increased mortality in patients with end-stage renal failure.......Increased oxidative stress, elevated plasma homocysteine concentration, increased pulse pressure, and impaired endothelial function constitute risk factors for increased mortality in patients with end-stage renal failure....

  12. High hydrostatic pressure: a new way to improve in vitro developmental competence of porcine matured oocytes after vitrification

    DEFF Research Database (Denmark)

    Du, Y; Pribenszky, C S; Molnár, M

    2008-01-01

    The purpose of the present study was to improve cryotolerance using high hydrostatic pressure (HHP) pretreatment of porcine in vitro matured (IVM) oocytes, to facilitate their further developmental competence after parthenogenetic activation. A total of 1668 porcine IVM oocytes were used in our...... present study. The pressure tolerance and optimal duration of recovery after HHP treatment were determined. Oocytes were treated with either 20 or 40 MPa (200 and 400 times greater than atmospheric pressure) for 60 min, with an interval of 10, 70, and 130 min between pressure treatment and subsequent...... vitrification under each pressure parameter. Oocytes from all vitrification groups had much lower developmental competence than fresh oocytes (Ppressure, with either 70...

  13. Sequential feeding using whole wheat and a separate protein-mineral concentrate improved feed efficiency in laying hens.

    Science.gov (United States)

    Umar Faruk, M; Bouvarel, I; Même, N; Rideau, N; Roffidal, L; Tukur, H M; Bastianelli, D; Nys, Y; Lescoat, P

    2010-04-01

    The effect of feeding nutritionally different diets in sequential or loose-mix systems on the performance of laying hen was investigated from 16 to 46 wk of age. Equal proportions of whole wheat grain and protein-mineral concentrate (balancer diet) were fed either alternatively (sequential) or together (loose-mix) to ISA Brown hens. The control was fed a complete layer diet conventionally. Each treatment was allocated 16 cages and each cage contained 5 birds. Light was provided 16 h daily (0400 to 2000 h). Feed offered was controlled (121 g/bird per d) and distributed twice (4 and 11 h after lights-on). In the sequential treatment, only wheat was fed at first distribution, followed by balancer diet at the second distribution. In loose-mix, the 2 rations were mixed and fed together during the 2 distributions. Leftover feed was always removed before the next distribution. Sequential feeding reduced total feed intake when compared with loose-mix and control. It had lower wheat (-9 g/bird per d) but higher balancer (+1.7 g/bird per d) intakes than loose-mix. Egg production, egg mass, and egg weight were similar among treatments. This led to an improvement in efficiency of feed utilization in sequential compared with loose-mix and control (10 and 5%, respectively). Birds fed sequentially had lower calculated ME (kcal/bird per d) intake than those fed in loose-mix and control. Calculated CP (g/bird per d) intake was reduced in sequential compared with loose-mix and control. Sequentially fed hens were lighter in BW. However, they had heavier gizzard, pancreas, and liver. Similar liver lipid was observed among treatments. Liver glycogen was higher in loose-mix than the 2 other treatments. It was concluded that feeding whole wheat and balancer diet, sequentially or loosely mixed, had no negative effect on performance in laying hens. Thus, the 2 systems are alternative to conventional feeding. The increased efficiency of feed utilization in sequential feeding is an added

  14. Ex vivo addition of fibrinogen concentrate improves the fibrin network structure in plasma samples taken during liver transplantation

    NARCIS (Netherlands)

    Groeneveld, D. J.; Adelmeijer, J.; Hugenholtz, G. C. G.; Ariens, R. A. S.; Porte, R. J.; Lisman, T.

    2015-01-01

    Background: Optimal hemostatic management during orthotopic liver transplantation (OLT) remains a challenge. The cause of bleeding during OLT is multifactorial, and may include hemostatic imbalance. Fibrinogen concentrates are increasingly being used to control perioperative bleeding during OLT.

  15. Improved concentration and separation of particles in a 3D dielectrophoretic chip integrating focusing, aligning and trapping

    KAUST Repository

    Li, Ming; Li, Shunbo; Cao, Wenbin; Li, Weihua; Wen, Weijia; Alici, Gursel

    2012-01-01

    This article presents a dielectrophoresis (DEP)-based microfluidic device with the three-dimensional (3D) microelectrode configuration for concentrating and separating particles in a continuous throughflow. The 3D electrode structure, where

  16. Tangential Flow Ultrafiltration Allows Purification and Concentration of Lauric Acid-/Albumin-Coated Particles for Improved Magnetic Treatment.

    Science.gov (United States)

    Zaloga, Jan; Stapf, Marcus; Nowak, Johannes; Pöttler, Marina; Friedrich, Ralf P; Tietze, Rainer; Lyer, Stefan; Lee, Geoffrey; Odenbach, Stefan; Hilger, Ingrid; Alexiou, Christoph

    2015-08-14

    Superparamagnetic iron oxide nanoparticles (SPIONs) are frequently used for drug targeting, hyperthermia and other biomedical purposes. Recently, we have reported the synthesis of lauric acid-/albumin-coated iron oxide nanoparticles SEON(LA-BSA), which were synthesized using excess albumin. For optimization of magnetic treatment applications, SPION suspensions need to be purified of excess surfactant and concentrated. Conventional methods for the purification and concentration of such ferrofluids often involve high shear stress and low purification rates for macromolecules, like albumin. In this work, removal of albumin by low shear stress tangential ultrafiltration and its influence on SEON(LA-BSA) particles was studied. Hydrodynamic size, surface properties and, consequently, colloidal stability of the nanoparticles remained unchanged by filtration or concentration up to four-fold (v/v). Thereby, the saturation magnetization of the suspension can be increased from 446.5 A/m up to 1667.9 A/m. In vitro analysis revealed that cellular uptake of SEON(LA-BSA) changed only marginally. The specific absorption rate (SAR) was not greatly affected by concentration. In contrast, the maximum temperature Tmax in magnetic hyperthermia is greatly enhanced from 44.4 °C up to 64.9 °C by the concentration of the particles up to 16.9 mg/mL total iron. Taken together, tangential ultrafiltration is feasible for purifying and concentrating complex hybrid coated SPION suspensions without negatively influencing specific particle characteristics. This enhances their potential for magnetic treatment.

  17. Using an aqueous two-phase polymer-salt system to rapidly concentrate viruses for improving the detection limit of the lateral-flow immunoassay.

    Science.gov (United States)

    Jue, Erik; Yamanishi, Cameron D; Chiu, Ricky Y T; Wu, Benjamin M; Kamei, Daniel T

    2014-12-01

    The development of point-of-need (PON) diagnostics for viruses has the potential to prevent pandemics and protects against biological warfare threats. Here we discuss the approach of using aqueous two-phase systems (ATPSs) to concentrate biomolecules prior to the lateral-flow immunoassay (LFA) for improved viral detection. In this paper, we developed a rapid PON detection assay as an extension to our previous proof-of-concept studies which used a micellar ATPS. We present our investigation of a more rapid polymer-salt ATPS that can drastically improve the assay time, and show that the phase containing the concentrated biomolecule can be extracted prior to macroscopic phase separation equilibrium without affecting the measured biomolecule concentration in that phase. We could therefore significantly decrease the time of the diagnostic assay with an early extraction time of just 30 min. Using this rapid ATPS, the model virus bacteriophage M13 was concentrated between approximately 2 and 10-fold by altering the volume ratio between the two phases. As the extracted virus-rich phase contained a high salt concentration which destabilized the colloidal gold indicator used in LFA, we decorated the gold nanoprobes with polyethylene glycol (PEG) to provide steric stabilization, and used these nanoprobes to demonstrate a 10-fold improvement in the LFA detection limit. Lastly, a MATLAB script was used to quantify the LFA results with and without the pre-concentration step. This approach of combining a rapid ATPS with LFA has great potential for PON applications, especially as greater concentration-fold improvements can be achieved by further varying the volume ratio. Biotechnol. Bioeng. 2014;111: 2499-2507. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  18. Improving Infant Exposure and Health Risk Estimates: Using Serum Data to Predict Polybrominated Diphenyl Ether Concentrations in Breast Milk

    Science.gov (United States)

    Women in the United States have breast milk concentrations of polybrominated diphenyl ethers (PBDEs) that are among the highest in the world, leading to concerns over the potential health implications to breastfeeding infants during critical stages of growth and development. Deve...

  19. Increasing synthetic serum substitute (SSS) concentrations in P1 glucose/phosphate-free medium improves implantation rate: a comparative study.

    Science.gov (United States)

    Ben-Yosef, D; Yovel, I; Schwartz, T; Azem, F; Lessing, J B; Amit, A

    2001-11-01

    To assess the comparative efficacy of IVF medium (MediCult, with 5.2 mM glucose) and a glucose/phosphate-free medium, P1 (Irvine Scientific), and to investigate the influence of increasing the serum supplementation (synthetic serum substitute; SSS; Irvine Scientific) to P1 on embryo development and implantation. Patients were randomly assigned to IVF medium (Group 1, cycles n = 172) or P1 supplemented with 10% SSS (Group 2, cycles n = 229) according to the medium scheduled for use on the day of oocyte retrieval. Another 555 IVF consequent cycles (Group 3) were performed using increased SSS concentrations (20%) in P1 medium. In this large series of IVF cycles, we herein demonstrate that significantly higher pregnancy and implantation rates were found when embryos were cultured in glucose/phosphate-free medium P1 supplemented with 20% SSS compared to supplementation with the lower SSS concentration and with IVF medium.

  20. A data mining approach to improve multiple regression models of soil nitrate concentration predictions in Quercus rotundifolia montados (Portugal)

    OpenAIRE

    Nunes, Jorge; Madeira, Manuel; Gazarini, Luiz; Neves, José; Vicente, Henrique

    2012-01-01

    The changes in the soil nitrate concentration were studied during 2 years in a ‘‘montado’’ ecosystem, in the South of Portugal. Total rainfall, air and soil temperature and soil water content under and outside Quercus rotundifolia canopy were also evaluated. A cluster analysis was carried out using climatic and microclimatic parameters in order to maximize the intraclass similarity and minimize the interclass similarity. It was used the k-Means Clustering Method. Se...

  1. Evaluating strategies to improve glucosinolate concentration and root yield of field-grown horseradish in a Mediterranean environment: preliminary results

    Directory of Open Access Journals (Sweden)

    Anna Rita Rivelli

    2016-03-01

    Full Text Available Horseradish is grown for its enlarged taproot that is widely used as a dish condiment and as a source of horseradish peroxidase. Nowadays, the species is gaining great interest due to the richness in bioactive compounds that besides providing a high nutritional value are tested for innovative applications in different fields. Nevertheless, the effect of crop management on root yield and glucosinolates (GLS biosynthesis is poorly documented. Aim of this study was to evaluate the root yield and GLS concentration of two field-grown horseradish accessions (Cor and Mon grown with nitrogen (N alone and both N and sulphur (S (-N-S, +N-S and +N+S treatments and harvested at different times [late autumn (LA, 2011 and 2012, early spring (ES, 2012]. Yield increased throughout the harvests up to 48% on average of the fertilised treatments and 25% in the unfertilised control. Conversely, root GLS concentration significantly declined in the unfertilised control throughout the harvests [from 7.6 in LA_2011 to 1.43 μmol/g dry matter (DM in LA_2012] while it highly increased in plants grown with N alone and with both N and S by 46 and 98%, respectively, from LA_2011 to ES_2012 (up to 11.9 and 21.1 μmol/g DM, respectively; then it drastically decreased by 80% on average, in the next harvest. Among individual GLS, the concentration of sinigrin and nasturtin similarly varied as effect of the analysed factors, showing the highest values in Cor accession. The data show that although the level of GLS is highly dependent on genotype, fertilisation and harvesting date may play a primary role in determining the yield and GLS concentration in horseradish root.

  2. Improving Arctic Sea Ice Edge Forecasts by Assimilating High Horizontal Resolution Sea Ice Concentration Data into the US Navy’s Ice Forecast Systems

    Science.gov (United States)

    2016-06-13

    1735-2015 © Author(s) 2015. CC Attribution 3.0 License. Improving Arctic sea ice edge forecasts by assimilating high horizontal resolution sea ice...concentration data into the US Navy’s ice forecast systems P. G. Posey1, E. J. Metzger1, A. J. Wallcraft1, D. A. Hebert1, R. A. Allard1, O. M. Smedstad2...error within the US Navy’s operational sea ice forecast systems gained by assimilating high horizontal resolution satellite-derived ice concentration

  3. A Comprehensive plan of improving water quality considering water system - concentrated on a basin of the Han River

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jee Yong; Moon, Hyun Joo; Yum, Kyu Jin; Kim, Eun Jung; Lee, Young Soon; Kim, Kang Suk; Lee, Chang Hee; Shin, Eun Sung; Kim, Jee Hoon [Korea Environment Institute, Seoul (Korea)

    1998-12-01

    The contents of this study are following: reviewing the present policy on land use in basin to improve the water quality of water supply source in Paldang and so on; improvement policy on land use in basin; management scheme of pollutant into Paldang; the variety and quantity of toxic substances, a control of particular pollutant; management of polluted deposit in Paldang; the control of efficient environment investment in upper stream of Paldang; financial assistance for damaged region; and purchasing land of sensitivity region for protecting water supply. 32 refs., 13 figs., 124 tabs.

  4. Effect of efficient supply of pure O2 concentrated by PSA-type O2 separator on improvement of indoor air quality

    International Nuclear Information System (INIS)

    Han, Gi Bo; Jang, Jung Hee; Choi, Changsik; Lee, Tae Jin

    2016-01-01

    To minimize the cost and loss rate of energy artificial room ventilation system, the O 2 separator was suggested for the flow of the excessive ventilation amount between indoor and outdoor because the pure O 2 separated and concentrated by the O 2 separator can be supplied with the ventilation amount minimized. How the O 2 separator applies to ventilation and its operation characteristics were investigated by controlling under various conditions as well as the operation conditions optimized required for indoor air quality such as the concentration of CO 2 and O 2 . Consequently, it was known that the O 2 concentration was increased; however, the increase of the CO 2 concentration was suppressed by the sufficient supply of O 2 concentrated from the storage tank into the room despite the two persons’ breathing in the room having an inner volume of about 56m 3 . Consequently, it was concluded that the supply system of the concentrated O 2 which was stored into the tank after the production with the O 2 separator can be applied to the room ventilation system for the improvement of the indoor air quality.

  5. Effect of efficient supply of pure O{sub 2} concentrated by PSA-type O{sub 2} separator on improvement of indoor air quality

    Energy Technology Data Exchange (ETDEWEB)

    Han, Gi Bo; Jang, Jung Hee; Choi, Changsik [Institute for Advanced Engineering, Yongin (Korea, Republic of); Lee, Tae Jin [School of Chemical Engineering Yeungnam University, Gyeongsan (Korea, Republic of)

    2016-04-15

    To minimize the cost and loss rate of energy artificial room ventilation system, the O{sub 2} separator was suggested for the flow of the excessive ventilation amount between indoor and outdoor because the pure O{sub 2} separated and concentrated by the O{sub 2} separator can be supplied with the ventilation amount minimized. How the O{sub 2} separator applies to ventilation and its operation characteristics were investigated by controlling under various conditions as well as the operation conditions optimized required for indoor air quality such as the concentration of CO{sub 2} and O{sub 2}. Consequently, it was known that the O{sub 2} concentration was increased; however, the increase of the CO{sub 2} concentration was suppressed by the sufficient supply of O{sub 2} concentrated from the storage tank into the room despite the two persons’ breathing in the room having an inner volume of about 56m{sup 3}. Consequently, it was concluded that the supply system of the concentrated O{sub 2} which was stored into the tank after the production with the O{sub 2} separator can be applied to the room ventilation system for the improvement of the indoor air quality.

  6. Optimizing Taq polymerase concentration for improved signal-to-noise in the broad range detection of low abundance bacteria.

    Directory of Open Access Journals (Sweden)

    Rudolph Spangler

    Full Text Available BACKGROUND: PCR in principle can detect a single target molecule in a reaction mixture. Contaminating bacterial DNA in reagents creates a practical limit on the use of PCR to detect dilute bacterial DNA in environmental or public health samples. The most pernicious source of contamination is microbial DNA in DNA polymerase preparations. Importantly, all commercial Taq polymerase preparations inevitably contain contaminating microbial DNA. Removal of DNA from an enzyme preparation is problematical. METHODOLOGY/PRINCIPAL FINDINGS: This report demonstrates that the background of contaminating DNA detected by quantitative PCR with broad host range primers can be decreased greater than 10-fold through the simple expedient of Taq enzyme dilution, without altering detection of target microbes in samples. The general method is: For any thermostable polymerase used for high-sensitivity detection, do a dilution series of the polymerase crossed with a dilution series of DNA or bacteria that work well with the test primers. For further work use the concentration of polymerase that gave the least signal in its negative control (H(2O while also not changing the threshold cycle for dilutions of spiked DNA or bacteria compared to higher concentrations of Taq polymerase. CONCLUSIONS/SIGNIFICANCE: It is clear from the studies shown in this report that a straightforward procedure of optimizing the Taq polymerase concentration achieved "treatment-free" attenuation of interference by contaminating bacterial DNA in Taq polymerase preparations. This procedure should facilitate detection and quantification with broad host range primers of a small number of bona fide bacteria (as few as one in a sample.

  7. Improving spatio-temporal model estimation of satellite-derived PM2.5 concentrations: Implications for public health

    Science.gov (United States)

    Barik, M. G.; Al-Hamdan, M. Z.; Crosson, W. L.; Yang, C. A.; Coffield, S. R.

    2017-12-01

    Satellite-derived environmental data, available in a range of spatio-temporal scales, are contributing to the growing use of health impact assessments of air pollution in the public health sector. Models developed using correlation of Moderate Resolution Imaging Spectrometer (MODIS) Aerosol Optical Depth (AOD) with ground measurements of fine particulate matter less than 2.5 microns (PM2.5) are widely applied to measure PM2.5 spatial and temporal variability. In the public health sector, associations of PM2.5 with respiratory and cardiovascular diseases are often investigated to quantify air quality impacts on these health concerns. In order to improve predictability of PM2.5 estimation using correlation models, we have included meteorological variables, higher-resolution AOD products and instantaneous PM2.5 observations into statistical estimation models. Our results showed that incorporation of high-resolution (1-km) Multi-Angle Implementation of Atmospheric Correction (MAIAC)-generated MODIS AOD, meteorological variables and instantaneous PM2.5 observations improved model performance in various parts of California (CA), USA, where single variable AOD-based models showed relatively weak performance. In this study, we further asked whether these improved models actually would be more successful for exploring associations of public health outcomes with estimated PM2.5. To answer this question, we geospatially investigated model-estimated PM2.5's relationship with respiratory and cardiovascular diseases such as asthma, high blood pressure, coronary heart disease, heart attack and stroke in CA using health data from the Centers for Disease Control and Prevention (CDC)'s Wide-ranging Online Data for Epidemiologic Research (WONDER) and the Behavioral Risk Factor Surveillance System (BRFSS). PM2.5 estimation from these improved models have the potential to improve our understanding of associations between public health concerns and air quality.

  8. A multielement trace mineral injection improves liver copper and selenium concentrations and manganese superoxide dismutase activity in beef steers.

    Science.gov (United States)

    Genther, O N; Hansen, S L

    2014-02-01

    Trace minerals (TM) are vital to health and growth of livestock, but low dietary concentrations and dietary antagonists may reduce mineral status and feeder cattle TM status is usually unknown at arrival. The objective of this study was to examine the effect of TM status on response to mineral injection in beef cattle. Forty steers were equally assigned to diets for an 84-d depletion period: control (CON; supplemental Cu, Mn, Se, and Zn) or deficient (DEF; no supplemental Cu, Mn, Se, or Zn plus Fe and Mo as TM antagonists). Lesser liver Cu and Se concentrations (79.0 ± 11.60 and 1.66 ± 0.080 mg/kg DM, respectively) in DEF steers compared with CON steers (228.8 ± 11.60 and 2.41 ± 0.080 mg/kg DM, respectively) on d 71 of depletion indicated mild deficiencies of these TM (P CON vs. DEF (P = 0.02), suggesting TM from injection were used rather than stored in DEF steers. Liver Se and Cu (P CON animals, total MPO was greater in animals that received TM injection, but injection did not affect MPO within DEF steers (P = 0.007). Overall, TM from an injectable mineral were used differently between TM adequate and mildly deficient steers.

  9. Improvements in glucose metabolism early after gastric bypass surgery are not explained by increases in total bile acids and fibroblast growth factor 19 concentrations

    DEFF Research Database (Denmark)

    Jørgensen, Nils B; Dirksen, Carsten; Bojsen-Møller, Kirstine N

    2015-01-01

    Context: Bile acids and fibroblast growth factor 19 (FGF19) have been suggested as key mediators of the improvements in glucose metabolism after Roux-en-Y gastric bypass (RYGB). Objective: To describe fasting and postprandial state total bile acid (TBA) and FGF19 concentrations before and after...... (T2D) patients and 12 normal glucose tolerant (NGT) subjects participated in the study. Intervention: A 4-hour liquid meal test was performed before and 1 week, 3 months, and 1 year after RYGB. Main Outcome Measures: We measured fasting and postprandial TBA and FGF19 concentrations. Results: Fasting...... TBA concentrations decreased in NGT subjects (P TBA was decreased in NGT subjects 1 week after RYGB (before surgery, 567...

  10. Improvement of a Vertical Falling Ball Viscometer for Measuring Engine Oil Properties using 532nm diode laser, with Estimation of the Concentration of operated Oil

    Directory of Open Access Journals (Sweden)

    Dawood O. Altaify

    2017-05-01

    Full Text Available In this work, an improvement of falling ball viscometer was presented using laser beam. Several parameters such as viscosity, shear stress, shear rate, Reynolds number and drag coefficient were calculated for a sample of unused engine oil. In the other words, during the operation of engine, the variation of viscosity occurs due to the increasing in the engine temperature and may in the increasing of the concentration of engine body particles inside the oil due to friction force even with existing the oil filter there are tiny particles that pass through the oil filter, therefore a Lambert’s law was used to estimate the particles concentrations of the operated oil, the resulted graphs show increasing of the impurities concentration with operation time.

  11. COMPARISON OF CONCENTRIC AND ECCENTRIC HAMSTRING STRENGTH TRAINING IN IMPROVING MUSCLE STRENGTH AND POWER AMONG FUTSAL PLAYERS A RANDOMIZED CONTROLLED TRIAL

    Directory of Open Access Journals (Sweden)

    Arunkumar Nedunchezhiyan

    2016-12-01

    Full Text Available Background: Hamstring injury is a common problem in many sports, especially those involving acceleration and maximal sprints. Hamstring strains are both common and painful. During sprinting the hip flexor and knee extensor torques are frequently produced and is opposed by the hamstring muscles, hence there are numerous studies done on the muscle strength training to prevent the hamstring strain injury as it is statistically stated as the highest rate involved injury in the contact sport. This study has been focused to evaluate the effectiveness of concentric and eccentric exercises in improving hamstring muscle strength and power among futsal players. Method: Thirty recreational futsal players were recruited for the study and were randomly divided into two groups. Each group received either hamstring curl exercise (concentric or Nordic hamstring exercise (eccentric twice a week for 4 weeks. The manual muscle test (MMT and 40-yard dash test was used to evaluate the muscle strength and power respectively by comparing the pretest and posttest values for both groups. Results: Wilcoxon signed rank test showed that there is no statistically significant difference between pre and post test values of MMT (Concentric (right side, z=.317; left side, z=.157, Eccentric (right side, z=.157; left side, z=.317 in both groups. Based on paired 't' test there is a significant difference between the pre and post test on improving muscle power [Concentric group, P=.020; Eccentric Group, P=.000]. Mann–Whitney U test and unpaired 't' test showed that there is no significant difference between both groups of MMT (z=.775 and 40-yard dash test (P=.707 respectively. Conclusion: The concentric strength training and eccentric strength training have a similar effect in improving hamstring muscle power in futsal players.

  12. Improvement of wine aromatic quality using mixtures of lysozyme and dimethyl dicarbonate, with low SO2 concentration.

    Science.gov (United States)

    Nieto-Rojo, Rodrigo; Luquin, Asuncion; Ancín-Azpilicueta, Carmen

    2015-01-01

    The use of sulphur dioxide (SO2) in the treatment of foodstuffs presents some problems as it could lead to pseudo-allergies in some people. The aim of this research work was to study the addition of different preservative mixtures and their influence on the concentration of volatile compounds and sensorial quality in wine. To do so, vinifications were carried out using Garnacha must to which lysozyme, dimethyl dicarbonate (DMDC) and mixtures of these with SO2 were added at different doses (25 and 50 mg l(-1)). The results were compared with a control sample to which only SO2 had been added (50 mg l(-1)). In general, mixtures of SO2 with lysozyme and DMDC favoured the formation of volatile compounds in the wines. Wines obtained from the mixtures of lysozyme and DMDC with 25 mg l(-1) of SO2 had better sensorial quality than the wines obtained with 50 mg l(-1) as the only preservative used.

  13. Plasma fluoxetine concentrations and clinical improvement in an adolescent sample diagnosed with major depressive disorder, obsessive-compulsive disorder, or generalized anxiety disorder.

    Science.gov (United States)

    Blázquez, Ana; Mas, Sergi; Plana, Maria Teresa; Gassó, Patricia; Méndez, Iria; Torra, Mercè; Arnaiz, Joan Albert; Lafuente, Amàlia; Lázaro, Luisa

    2014-06-01

    Fluoxetine (FLX) has been one of the most widely studied selective serotonin reuptake inhibitors in adolescents. Despite its efficacy, however, 30% to 40% of patients do not respond to treatment. The aim of this study was to evaluate whether clinical improvement or adverse events are related to the corrected dose of FLX at 8 and 12 weeks after starting treatment in a sample of adolescents diagnosed with major depressive disorder, obsessive-compulsive disorder, or generalized anxiety disorder. Seventy-four subjects aged between 10 and 17 years participated in the study. Clinical improvement was measured with the Clinical Global Impression-Improvement Scale, whereas the UKU (Udvalg for Klinske Undersogelser) scale was administered to assess adverse effects of treatment. Fluoxetine per kilograms of body weight was related to serum concentration of FLX, NORFLX (norfluoxetine), FLX + NORFLX, and FLX/NORFLX. No relationship was found between dose-corrected FLX levels and therapeutic or adverse effects. No differences in serum concentrations were found between responders and nonresponders to treatment. Sex differences were observed in relation to dose and FLX serum concentration. The analysis by diagnosis revealed differences in FLX dose between obsessive-compulsive disorder patients and both generalized anxiety disorder and major depressive disorder patients. Fluoxetine response seems to be influenced by factors such as sex, diagnosis, or certain genes that might be involved in the drug's pharmacokinetics and pharmacodynamics. Clinical and pharmacogenetic studies are needed to elucidate further the differences between treatment responders and nonresponders.

  14. A modified HPLC method improves the simultaneous determination of plasma kynurenine and tryptophan concentrations in patients following maintenance hemodialysis

    Science.gov (United States)

    XIAO, CHENGGEN; CHEN, YUANHAN; LIANG, XINLING; XIE, ZHEN; ZHANG, MIN; LI, RUIZHAO; LI, ZHILIAN; FU, XIA; YU, XIYONG; SHI, WEI

    2014-01-01

    The ratio between plasma kynurenine (Kyn) and tryptophan (Trp) serves as a marker of indoleamine 2,3-dioxygenase, a critical immunomodulatory molecule. Simultaneous detection of the two markers may be performed using high-pressure liquid chromatography (HPLC). However, for uremic patients, the conventional detection method may be affected by a range of accumulated toxins. The current study aimed to establish a method for the simultaneous measurement of Kyn and Trp in patients following maintenance hemodialysis via HPLC-ultraviolet detection. The procedure involved the use of a SinoChrom ODS-BP C18 column (4.6×150 mm; inner diameter, 4.5 μm) and a mobile phase of 15 mmol/l sodium acetate acetic acid solution (containing 5% acetonitrile, pH 4.8). The modified method was verified using plasma samples from 10 healthy controls and 91 maintenance hemodialysis patients. The results demonstrated that the modified method was successful in simultaneously detecting the concentrations of Trp and Kyn in the healthy controls and maintenance hemodialysis patients. The method is simple, fast, accurate and suitable for clinical and research purposes in maintenance hemodialysis patients. PMID:24669249

  15. N/P GaAs concentrator solar cells with an improved grid and bushbar contact design

    International Nuclear Information System (INIS)

    Desalvo, G.C.; Mueller, E.H.; Barnett, A.M.

    1985-01-01

    The major requirements for a solar cell used in space applications are high efficiency at AMO irradiance and resistance to high energy radiation. Gallium arsenide, with a band gap of 1.43 eV, is one of the most efficient sunlight to electricity converters (25%) when the the simple diode model is used to calculate efficiencies at AMO irradiance, GaAs solar cells are more radiation resistant than silicon solar cells and the N/P GaAs device has been reported to be more radiation resistant than similar P/N solar cells. This higher resistance is probably due to the fact that only 37% of the current is generated in the top N layer of the N/P cell compared to 69% in the top layer of a P/N solar cell. This top layer of the cell is most affected by radiation. It has also been theoretically calculated that the optimized N/P device will prove to have a higher efficiency than a similar P/N device. The use of a GaP window layer on a GaAs solar cell will avoid many of the inherent problems normally associated with a GaAlAs window while still proving good passivation of the GaAs surface. An optimized circular grid design for solar cell concentrators has been shown which incorporates a multi-layer metallization scheme. This multi-layer design allows for a greater current carrying capacity for a unit area of shading, which results in a better output efficiency

  16. Caffeine ingestion after rapid weight loss in judo athletes reduces perceived effort and increases plasma lactate concentration without improving performance.

    Science.gov (United States)

    Lopes-Silva, Joao P; Felippe, Leandro J C; Silva-Cavalcante, Marcos D; Bertuzzi, Romulo; Lima-Silva, Adriano E

    2014-07-22

    The objective of this study was to examine the effect of caffeine on judo performance, perceived exertion, and plasma lactate response when ingested during recovery from a 5-day weight loss period. Six judokas performed two cycles of a 5-day rapid weight loss procedure to reduce their body weight by ~5%. After weigh-in, subjects re-fed and rehydrated over a 4-h recovery period. In the third hour of this "loading period", subjects ingested a capsule containing either caffeine (6 mg·kg-1) or placebo. One hour later, participants performed three bouts of a judo fitness test with 5-min recovery periods. Perceived exertion and plasma lactate were measured before and immediately after each test bout. Body weight was reduced in both caffeine and placebo conditions after the weight loss period (-3.9% ± 1.6% and -4.0% ± 2.3% from control, respectively, p caffeine or placebo groups. However, plasma lactate was systemically higher and perceived exertion lower in the subjects who ingested caffeine compared to either the control or placebo subjects (p caffeine did not improve performance during the judo fitness test after a 5-day weight loss period, but reduced perceived exertion and increased plasma lactate.

  17. Improvement of physico-chemical properties and phenolic compounds bioavailability by concentrating dietary fiber of peach (Prunus persica) juice by-product.

    Science.gov (United States)

    Rodríguez-González, Sarahí; Pérez-Ramírez, Iza F; Castaño-Tostado, Eduardo; Amaya-Llano, Silvia; Rodríguez-García, Mario E; Reynoso-Camacho, Rosalía

    2018-06-01

    This study aimed to concentrate dietary fiber (DF) from peach (Prunus persica) juice by-product (PJBP), to improve its functional properties, and its polyphenols bioavailability. The dietary fiber concentrates (DFCs) were obtained from PJBP using water/ethanol treatments (100:0, 20:80, 50:50, 80:20, and 0:100, v/v) at 1:5 ratio (wet weight/solvent, w/v) for 5 and 20 min at 21 °C. All treatments concentrated condensed tannins, total and insoluble DF, with the highest content found with 100% H 2 O treatment. The major polyphenols of DFC were 4-O-caffeoylquinic, chlorogenic, and 1,5-di-O-caffeoylquinic acids. Water and oil retention capacity and maximum glucose diffusion rate were improved mainly with 100% H 2 O treatment. Healthy rats were fed with a standard diet supplemented with 8% of PJBP, DFC obtained with 100% H 2 O for 5 min, or DFC obtained with 20% EtOH for 5 min. Gastrointestinal digesta weight and viscosity were increased in animals supplemented with 100% H 2 O DFC. Moreover, the urinary excretion of polyphenol metabolites, mainly glucuronide and sulfate conjugates, was increased with this treatment, indicating a greater bioavailability of PJBP polyphenols, which was associated with an increased dietary fiber porosity. Water treatment could be used to potentiate PJBP functional properties and polyphenols bioavailability. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Low concentration of sodium bicarbonate improves the bioactive compound levels and antioxidant and α-glucosidase inhibitory activities of tartary buckwheat sprouts.

    Science.gov (United States)

    Qin, Peiyou; Wei, Aichun; Zhao, Degang; Yao, Yang; Yang, Xiushi; Dun, Baoqing; Ren, Guixing

    2017-06-01

    This study aimed to investigate the effects of different concentrations of sodium bicarbonate (NaHCO 3 ) on the accumulation of flavonoids, total phenolics and d-chiro-inositol (DCI), as well as the antioxidant and α-glucosidase inhibitory activities, in tartary buckwheat sprouts. Treatment with low concentrations of NaHCO 3 (0.05, 0.1, and 0.2%) resulted in an increase in flavonoids, total phenolic compounds and DCI concentrations, and improved DPPH radical-scavenging and α-glucosidase inhibition activities compared with the control (0%). The highest levels of total flavonoids (26.69mg/g DW), individual flavonoids (rutin, isoquercitrin, quercetin, and kaempferol), total phenolic compounds (29.31mg/g DW), DCI (12.56mg/g DW), as well as antioxidant and α-glucosidase inhibition activities, were observed in tartary buckwheat sprouts treated with 0.05% NaHCO 3 for 96h. These results indicated that appropriate treatment with NaHCO 3 could improve the healthy benefits of tartary buckwheat sprouts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Caffeine Ingestion after Rapid Weight Loss in Judo Athletes Reduces Perceived Effort and Increases Plasma Lactate Concentration without Improving Performance

    Directory of Open Access Journals (Sweden)

    Joao P. Lopes-Silva

    2014-07-01

    Full Text Available The objective of this study was to examine the effect of caffeine on judo performance, perceived exertion, and plasma lactate response when ingested during recovery from a 5-day weight loss period. Six judokas performed two cycles of a 5-day rapid weight loss procedure to reduce their body weight by ~5%. After weigh-in, subjects re-fed and rehydrated over a 4-h recovery period. In the third hour of this “loading period”, subjects ingested a capsule containing either caffeine (6 mg·kg−1 or placebo. One hour later, participants performed three bouts of a judo fitness test with 5-min recovery periods. Perceived exertion and plasma lactate were measured before and immediately after each test bout. Body weight was reduced in both caffeine and placebo conditions after the weight loss period (−3.9% ± 1.6% and −4.0% ± 2.3% from control, respectively, p < 0.05. At three hours after weigh-in, body weight had increased with both treatments but remained below the control (−3.0% ± 1.3% and −2.7% ± 2.2%. There were no significant differences in the number of throws between the control, caffeine or placebo groups. However, plasma lactate was systemically higher and perceived exertion lower in the subjects who ingested caffeine compared to either the control or placebo subjects (p < 0.05. In conclusion, caffeine did not improve performance during the judo fitness test after a 5-day weight loss period, but reduced perceived exertion and increased plasma lactate.

  20. Long-Term Supplementation with Beta Serum Concentrate (BSC, a Complex of Milk Lipids, during Post-Natal Brain Development Improves Memory in Rats

    Directory of Open Access Journals (Sweden)

    Jian Guan

    2015-06-01

    Full Text Available We have previously reported that the supplementation of ganglioside-enriched complex-milk-lipids improves cognitive function and that a phospholipid-enriched complex-milk-lipid prevents age-related cognitive decline in rats. This current study evaluated the effects of post-natal supplementation of ganglioside- and phospholipid-enriched complex-milk-lipids beta serum concentrate (BSC on cognitive function in young rats. The diet of male rats was supplemented with either gels formulated BSC (n = 16 or blank gels (n = 16 from post-natal day 10 to day 70. Memory and anxiety-like behaviors were evaluated using the Morris water maze, dark–light boxes, and elevated plus maze tests. Neuroplasticity and white matter were measured using immunohistochemical staining. The overall performance in seven-day acquisition trials was similar between the groups. Compared with the control group, BSC supplementation reduced the latency to the platform during day one of the acquisition tests. Supplementation improved memory by showing reduced latency and improved path efficiency to the platform quadrant, and smaller initial heading error from the platform zone. Supplemented rats showed an increase in striatal dopamine terminals and hippocampal glutamate receptors. Thus BSC supplementation during post-natal brain development improved learning and memory, independent from anxiety. The moderately enhanced neuroplasticity in dopamine and glutamate may be biological changes underlying the improved cognitive function.

  1. Supplementation of Merino ewes with vitamin E plus selenium increases α-tocopherol and selenium concentrations in plasma of the lamb but does not improve their immune function.

    Science.gov (United States)

    Sterndale, S; Broomfield, S; Currie, A; Hancock, S; Kearney, G A; Lei, J; Liu, S; Lockwood, A; Scanlan, V; Smith, G; Thompson, A N

    2018-05-01

    Vitamin E and selenium have been reported to improve immune function across a range of species. Ewes lambing on poor-quality dry pasture in autumn in Western Australia are at risk of being deficient in vitamin E and selenium at lambing thus predisposing their lambs to deficiencies and increasing the risk of infection and disease. This study tested the hypotheses that (i) supplementation of autumn-lambing ewes with vitamin E plus selenium in late gestation will increase the concentrations of vitamin E and selenium in plasma in the ewe and lamb and (ii) that the increased concentrations of vitamin E and selenium in plasma in the lambs will improve their innate and adaptive immune responses and thus survival. Pregnant Merino ewes were divided into a control group (n=58) which received no supplementation or a group supplemented with vitamin E plus selenium (n=55). On days 111, 125 and 140 of pregnancy ewes in the vitamin E plus selenium group were given 4 g all-rac-α-tocopherol acetate orally. On day 111 the ewes were also given 60 mg of selenium as barium selenate by subcutaneous injection. The concentrations of α-tocopherol and selenium were measured in ewes and/or lambs from day 111 of pregnancy to 14 weeks of age±10 days (weaning). Immune function of the lamb was assessed by analysing the numbers and phagocytic capacities of monocytes and polymorphonuclear leucocytes and plasma IgG and anti-tetanus toxoid antibody concentrations between birth and 14 weeks of age±10 days. Maternal supplementation with vitamin E plus selenium increased the concentration of α-tocopherol in plasma (1.13 v. 0.67 mg/l; P<0.001) and selenium in whole blood (0.12 v. 0.07 mg/l; P<0.01) of the ewes at lambing compared with controls. Supplementation also increased the concentration of α-tocopherol (0.14 v. 0.08 mg/l; P<0.001) and selenium (0.08 v. 0.05 mg/l; P<0.01) in lambs at birth compared with controls. There was no significant effect of supplementation on immune function or

  2. Measurements and modeling of CO2 concentration and isotopes to improve process-level understanding of Arctic and boreal carbon cycling. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Keeling, Ralph F. [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography

    2017-09-29

    The major goal of this project was to improve understanding of processes that control the exchanges of CO2 between the atmosphere and the land biosphere on decadal and longer time scales. The approach involves measuring the changes in atmospheric CO2 concentration and the isotopes of CO2 (13C/12C and 18O/16O) at background stations and uses these and other datasets to challenge and improve numerical models of the earth system. The project particularly emphasized the use of these data to improve understanding of changes occurring in boreal and arctic ecosystems over the past 50 years and to seek from these data improved understanding of large-scale processes impacting carbon cycling, such as the responses to warming, CO2 fertilization, and disturbance. The project also led to advances in the understanding of changes in water-use efficiency of land ecosystems globally based on trends in 13C/12C. The core element of this project was providing partial support for continuing measurements of CO2 concentrations and isotopes from the Scripps CO2 program, initiated by C. D. Keeling in the 1960s. The measurements included analysis of flasks collected at an array of ten stations distributed from the Arctic to the Antarctic. The project also supported modeling studies and interpretive work to help understand the origins of the large ~50% increase in the amplitude of the atmospheric CO2 cycle detected at high northern latitudes between 1960 and present and to understand the long-term trend in carbon 13C/12C of CO2. The seasonal cycle work was advanced through collaborations with colleagues at MPI Jena and Imperial College

  3. Treatment of β-Thalassemia/Hemoglobin E with Antioxidant Cocktails Results in Decreased Oxidative Stress, Increased Hemoglobin Concentration, and Improvement of the Hypercoagulable State

    Directory of Open Access Journals (Sweden)

    Orn-uma Yanpanitch

    2015-01-01

    Full Text Available Studies on the antioxidant treatment for thalassemia have reported variable outcomes. However, treatment of thalassemia with a combination of hydrophobic and hydrophilic antioxidants and an iron chelator has not been studied. This study investigated the effects of antioxidant cocktails for the treatment of β-thalassemia/hemoglobin E (HbE, which is the most common form of β-thalassemia in Southeast Asia. Sixty patients were divided into two groups receiving N-acetylcysteine, deferiprone, and either curcuminoids (CUR or vitamin E (Vit-E, and their hematological parameters, iron load, oxidative stress, and blood coagulation potential were evaluated. Patients were classified as responders if they showed the improvements of the markers of iron load and oxidative stress, otherwise as nonresponders. During treatment, the responders in both groups had significantly decreased iron load, oxidative stress, and coagulation potential and significantly increased antioxidant capacity and hemoglobin concentration. The significantly maximum increase (P<0.01 in hemoglobin concentration was 11% at month 4 in CUR group responders and 10% at month 10 in Vit-E group responders. In conclusion, the two antioxidant cocktails can improve anemia, iron overload, oxidative stress, and hypercoagulable state in β-thalassemia/HbE.

  4. Slow-release nitrogen fertilizers can improve yield and reduce Cd concentration in pakchoi (Brassica chinensis L.) grown in Cd-contaminated soil.

    Science.gov (United States)

    Zhang, Ran-Ran; Liu, Yue; Xue, Wan-Lei; Chen, Rong-Xin; Du, Shao-Ting; Jin, Chong-Wei

    2016-12-01

    Cadmium (Cd) pollution in vegetable crops has become a serious problem in recent years. Owing to the limited availability of arable land resources, large areas of Cd-contaminated lands are inevitably being used for the production of vegetables, posing great risks to human health via the food chain. However, strategies to improve yield and reduce Cd concentration in crops grown in contaminated soils are being developed. In the present study, using pot experiments, we investigated the effects of two slow-release nitrogen fertilizers (SRNFs), resin-coated ammonium nitrate (Osmocote 313s ), and resin-coated urea (urea 620 ), on the growth and Cd concentration of the Cd-contaminated pakchoi. The results showed that pakchoi grown in soil containing 5 mg kg -1 of Cd-induced oxidative stress (indicated by malondialdehyde (MDA), H 2 O 2 , and O 2 ·- ) and photosynthesis inhibition, which in turn was restored with the application of SRNFs. However, pakchoi grown in Cd-contaminated soil supplied with Osmocote 313s and urea 620 showed 103 and 203 % increase in fresh weight and 51-55 % and 44-56 % decrease in Cd concentration, respectively, as compared with their controls (pakchoi treated with instant soluble nitrogen fertilizers). On the basis of an increase in their tolerance index (47-238 %) and a decrease in their translocation factor (7.5-21.6 %), we inferred that the plants treated with SRNFs have a stronger tolerance to Cd and a lower efficiency of Cd translocation to edible parts than those treated with instant soluble nitrogen fertilizers. Therefore, in terms of both crop production and food safety, application of SRNFs could be an effective strategy for improving both biomass production and quality in pakchoi grown under Cd stress.

  5. N-3 polyunsaturated fatty acids improve lipoprotein particle size and concentration in Japanese patients with type 2 diabetes and hypertriglyceridemia: a pilot study.

    Science.gov (United States)

    Ide, Kana; Koshizaka, Masaya; Tokuyama, Hirotake; Tokuyama, Takahiko; Ishikawa, Takahiro; Maezawa, Yoshiro; Takemoto, Minoru; Yokote, Koutaro

    2018-03-15

    Patients with type 2 diabetes are at high risk for cardiovascular disease. Although hydroxymethylglutaryl-CoA reductase inhibitors (statins) can reduce cardiovascular events, residual risk remains even after target low-density lipoprotein cholesterol (LDL-C) levels have been achieved. Lipoprotein particle size and fraction changes are thought to contribute to such risks. The purpose of this study was to evaluate the effects of n-3 polyunsaturated fatty acids (n-3 PUFAs), predominantly eicosapentaenoic acid and docosahexaenoic acid, on lipoprotein particle size, concentration, and glycemic control in Japanese patients with type 2 diabetes and hypertriglyceridemia. This was a multicenter, prospective, open-label, single arm study. We enrolled 14 patients with type 2 diabetes and hypertriglyceridemia treated with statins and dipeptidyl peptidase-4 inhibitors with glycated hemoglobin (HbA1c) n-3 PUFAs for 12 weeks. Lipoprotein particle sizes, concentrations, lipoprotein insulin resistance (LPIR) scores, lipid profiles, HbA1c, and fasting plasma glucose (FPG) were measured before and after treatment. Lipoprotein profiles were measured by nuclear magnetic resonance spectroscopy. Data were analyzed using Wilcoxon signed-rank tests. Concentrations of total cholesterol (P n-3 PUFA administration. N-3 PUFAs decreased the size of very low-density lipoprotein (VLDL; P N-3 PUFAs partly improved atherogenic lipoprotein particle size and concentration, and produced less atherogenic lipoprotein subclass ratios in patients that achieved target LDL-C levels and glycemic control. These results suggest that n-3 PUFAs may reduce residual cardiovascular risk factors in statin-treated patients with type 2 diabetes and hypertriglyceridemia. The study was registered at UMIN-ID: UMIN000013776 .

  6. Humid Heat Autoclaving of Hybrid Nanoparticles Achieved by Decreased Nanoparticle Concentration and Improved Nanoparticle Stability Using Medium Chain Triglycerides as a Modifier.

    Science.gov (United States)

    Gou, Jingxin; Chao, Yanhui; Liang, Yuheng; Zhang, Ning; He, Haibing; Yin, Tian; Zhang, Yu; Xu, Hui; Tang, Xing

    2016-09-01

    Humid heat autoclaving is a facile technique widely used in the sterilization of injections, but the high temperature employed would destroy nanoparticles composed of biodegradable polymers. The aim of this study was to investigate whether incorporation of medium chain triglycerides (MCT) could stabilize nanoparticles composed of poly (ethylene glycol)-b-polycaprolactone (PEG-b-PCL) during autoclaving (121°C, 10 min). Polymeric nanoparticles with different MCT contents were prepared by dialysis. Block copolymer degradation was studied by GPC. The critical aggregation concentrations of nanoparticles at different temperatures were determined using pyrene fluorescence. The size, morphology and weight averaged molecular weight of pristine/autoclaved nanoparticles were studied using DLS, TEM and SLS, respectively. Drug loading content and release profile were determined using RP-HPLC. The protecting effect of MCT on nanoparticles was dependent on the amount of MCT incorporated. Nanoparticles with high MCT contents, which assumed an emulsion-like morphology, showed reduced block copolymer degradation and particle disassociation after incubation at 100°C for 24 h. Nanoparticles with high MCT content showed the lowest critical aggregation concentration (CAC) under either room temperature or 60°C and the lowest particle concentration among all samples. And the particle size, drug loading content, physical stability and release profile of nanoparticles with high MCT contents remained nearly unchanged after autoclaving. Incorporation of high amount of MCT changed the morphology of PEG-b-PCL based nanoparticles to an emulsion-like structure and the nanoparticles prepared could withstand autoclaving due to improved particle stability and decreased particle concentration caused by MCT incorporation.

  7. Improved Technique for the Determination of Uranium Minor Isotopes Concentrations in Microparticles by Using Secondary Ion Mass-Spectrometer in Multicollection Mode

    International Nuclear Information System (INIS)

    Aleshin, M.; Elantyev, I.; Stebelkov, Y.

    2015-01-01

    Traditional method of the analysis implies simultaneous measuring of secondary ion currents of isotopes 234U + , 235U + , 238U + , ions with mass 236 amu (236U + and 235UH + ) and hydride ions 238UH + by using mass-spectrometer Cameca IMS1280 in multicollection mode. Calculating of uranium isotopic composition is performed using the results of 40 successive measurements of those currents (cycles). Duration of each measurement is 8 s. Small amounts of uranium minor isotopes are limitation for precise determination of their concentrations. To prevent the damage of the secondary ions detector the intensity of ion current should be no more than 5 x 10 5 s -1 . This limitation does not allow setting a higher primary ion current for the increasing of minor uranium isotopes ions emission because of the signal of ions 238U + gets too high. New technique is developed to improve the accuracy of determination of uranium minor isotopes concentrations. Process of measurement is divided on two steps. First step is a measurement of ion currents during 20 cycles by five detectors. The second step implies the elimination of ions 238U + hitting to the detector and 10 times increasing of primary ion current. The ratio 235U/238U is calculated from the first step results, so uncertainty of determination of this value is 1.4 times bigger than with duration of 40 cycles of the measurement. The ratios 234U/235U and 236U/235U are calculated during the second step. This technique allows to determine content of 234U and 236U with 3 and 5 times less uncertainties respectively, but with different degree of the sputtering particles. Moreover the duration of each cycle was set less (1 second) to use data more efficient. The technique accordingly with every second counting provides uncertainty of determination 236U concentration 4 times less than traditional method at the same degree of sputtering particles. (author)

  8. Arctic Ocean CO2 uptake: an improved multiyear estimate of the air-sea CO2 flux incorporating chlorophyll a concentrations

    Science.gov (United States)

    Yasunaka, Sayaka; Siswanto, Eko; Olsen, Are; Hoppema, Mario; Watanabe, Eiji; Fransson, Agneta; Chierici, Melissa; Murata, Akihiko; Lauvset, Siv K.; Wanninkhof, Rik; Takahashi, Taro; Kosugi, Naohiro; Omar, Abdirahman M.; van Heuven, Steven; Mathis, Jeremy T.

    2018-03-01

    We estimated monthly air-sea CO2 fluxes in the Arctic Ocean and its adjacent seas north of 60° N from 1997 to 2014. This was done by mapping partial pressure of CO2 in the surface water (pCO2w) using a self-organizing map (SOM) technique incorporating chlorophyll a concentration (Chl a), sea surface temperature, sea surface salinity, sea ice concentration, atmospheric CO2 mixing ratio, and geographical position. We applied new algorithms for extracting Chl a from satellite remote sensing reflectance with close examination of uncertainty of the obtained Chl a values. The overall relationship between pCO2w and Chl a was negative, whereas the relationship varied among seasons and regions. The addition of Chl a as a parameter in the SOM process enabled us to improve the estimate of pCO2w, particularly via better representation of its decline in spring, which resulted from biologically mediated pCO2w reduction. As a result of the inclusion of Chl a, the uncertainty in the CO2 flux estimate was reduced, with a net annual Arctic Ocean CO2 uptake of 180 ± 130 Tg C yr-1. Seasonal to interannual variation in the CO2 influx was also calculated.

  9. Improved of effective wetting area and film thickness on a concentric helical bank of a generator for an absorption heat transformer

    International Nuclear Information System (INIS)

    Lazcano-Véliz, Y.; Hernández, J.A.; Juárez-Romero, D.; Huicochea-Rodríguez, A.; Álvarez-Gallegos, A.; Siqueiros, J.

    2016-01-01

    Highlights: • The falling film of lithium bromide - water was improved in the generator of an AHT. • The design of the distributor and the concentric tube helical bank was modified. • Wetting efficiency for different operation conditions was obtained. • Improved operation flow in the heat exchange system was determined. - Abstract: This work was performed in the generator of an absorption heat transformer (AHT) applied for water purification, which has two concentric helical coils. The AHT used LiBr-H_2O to 55%wt for the heat transfer through a heat exchange by falling film. The objective of this study was to define the operating condition of the generator. Different falling film regimes were analyzed: drop mode, liquid column, and jet mode. The effective area of heat transfer of the two helical coils, wetting efficiency, and experimental film thickness were determined for the four operating flows (0.003, 0.008, 0.014, 0.019 kg/s) through digital image processing. The theoretical film thickness was measured and compared with the one calculated by the Nusselt equation. The flow of 0.008 kg/s maintained a drop mode distribution favoring a homogeneous fall along the helical test bank. A wetting efficiency of 99.52% was obtained, so it is proposed as operating flow in the generator. The theoretical film thickness for this flow was 0.289 cm and the one obtained experimentally through digital image processing was 0.293 cm. It was concluded that the distribution in the drop mode was more favorable for a better efficiency in the values of the falling film exchangers.

  10. Four-factor prothrombin complex concentrate improves thrombin generation and prothrombin time in patients with bleeding complications related to rivaroxaban: a single-center pilot trial.

    Science.gov (United States)

    Schenk, Bettina; Goerke, Stephanie; Beer, Ronny; Helbok, Raimund; Fries, Dietmar; Bachler, Mirjam

    2018-01-01

    Direct oral anticoagulants (DOACs) pose a great challenge for physicians in life-threatening bleeding events. The aim of this study was to test the efficacy of reversing the DOAC rivaroxaban using four-factor PCC (prothrombin complex concentrate), a non-specific reversing agent. Patients with life-threatening bleeding events during rivaroxaban treatment were included and administered 25 U kg -1 of PCC. Blood samples were collected immediately prior to as well as after PCC treatment at predefined time intervals. The primary endpoint was defined as the difference in thrombin generation (TG) parameters ETP (endogenous thrombin potential) and C max (peak thrombin generation) prior to and ten minutes subsequent to PCC treatment. Thirteen patients, of whom the majority suffered from intra-cranial haemorrhage (ICH) or subdural haemorrhage (SDH), were included and administered PCC. The results show that the ETP (TG) significantly ( p  = 0.001) improved by 68% and C max (TG) by 54% (p = 0.001) during PCC treatment. In addition, the Quick value (prothrombin time: Quick PT ) significantly improved by 28% and the activated partial thromboplastin time (aPTT) was decreased by 7% ten minutes after PCC administration. C max was reduced at baseline, but not ETP, aPTT or Quick PT . Lag time until initiation (TG, t lag ), thromboelastometry clotting time (CT EXTEM ) and time to peak (TG, t max ) correlated best with measured rivaroxaban levels and were out of normal ranges at baseline, but did not improve after PCC administration. In 77% of the patients bleeding (ICH/SDH-progression) ceased following PCC administration. During the study three participants passed away due to other complications not related to PCC treatment. The possibility of thrombosis formation was also evaluated seven days after administering PCC and no thromboses were found. This study shows that use of PCC improved ETP, C max, Quick PT and aPTT. However, of these parameters, only C max was reduced at the

  11. Concentrated Ownership

    DEFF Research Database (Denmark)

    Rose, Caspar

    2014-01-01

    This entry summarizes the main theoretical contributions and empirical findings in relation to concentrated ownership from a law and economics perspective. The various forms of concentrated ownership are described as well as analyzed from the perspective of the legal protection of investors......, especially minority shareholders. Concentrated ownership is associated with benefits and costs. Concentrated ownership may reduce agency costs by increased monitoring of top management. However, concentrated ownership may also provide dominating owners with private benefits of control....

  12. A strain of Saccharomyces cerevisiae evolved for fermentation of lignocellulosic biomass displays improved growth and fermentative ability in high solids concentrations and in the presence of inhibitory compounds

    Directory of Open Access Journals (Sweden)

    Hawkins Gary M

    2011-11-01

    Full Text Available Abstract Background Softwoods are the dominant source of lignocellulosic biomass in the northern hemisphere, and have been investigated worldwide as a renewable substrate for cellulosic ethanol production. One challenge to using softwoods, which is particularly acute with pine, is that the pretreatment process produces inhibitory compounds detrimental to the growth and metabolic activity of fermenting organisms. To overcome the challenge of bioconversion in the presence of inhibitory compounds, especially at high solids loading, a strain of Saccharomyces cerevisiae was subjected to evolutionary engineering and adaptation for fermentation of pretreated pine wood (Pinus taeda. Results An industrial strain of Saccharomyces, XR122N, was evolved using pretreated pine; the resulting daughter strain, AJP50, produced ethanol much more rapidly than its parent in fermentations of pretreated pine. Adaptation, by preculturing of the industrial yeast XR122N and the evolved strains in 7% dry weight per volume (w/v pretreated pine solids prior to inoculation into higher solids concentrations, improved fermentation performance of all strains compared with direct inoculation into high solids. Growth comparisons between XR122N and AJP50 in model hydrolysate media containing inhibitory compounds found in pretreated biomass showed that AJP50 exited lag phase faster under all conditions tested. This was due, in part, to the ability of AJP50 to rapidly convert furfural and hydroxymethylfurfural to their less toxic alcohol derivatives, and to recover from reactive oxygen species damage more quickly than XR122N. Under industrially relevant conditions of 17.5% w/v pretreated pine solids loading, additional evolutionary engineering was required to decrease the pronounced lag phase. Using a combination of adaptation by inoculation first into a solids loading of 7% w/v for 24 hours, followed by a 10% v/v inoculum (approximately equivalent to 1 g/L dry cell weight into 17

  13. Elliptical concentrators.

    Science.gov (United States)

    Garcia-Botella, Angel; Fernandez-Balbuena, Antonio Alvarez; Bernabeu, Eusebio

    2006-10-10

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used to produce optical devices, including the use of reflective and refractive components or inverse engineering techniques. However, many of these optical components are based on translational symmetries, rotational symmetries, or free-form surfaces. We study a new family of nonimaging concentrators called elliptical concentrators. This new family of concentrators provides new capabilities and can have different configurations, either homofocal or nonhomofocal. Translational and rotational concentrators can be considered as particular cases of elliptical concentrators.

  14. Replacement of lumpy chrome ore by agglomerated ore concentrates and lowering of specific power consumption and improvement of Cr-yield by means of improved slag composition in the production of H.C. Ferrochrome

    International Nuclear Information System (INIS)

    Retelsdorf, H.J.; Fichte, R.; Breuer, F.; Zimmermann, H.

    1982-06-01

    Work on this project is finished, but further work on the use of Cr-ore briquettes seems necessary. It was the aim of the project to develop improved slag compositions for the FeCr 4-6% C-process resulting in higher Cr-yield and lower specific power consumption. Furthermore, replacement of lumpy ore in the charge by agglomerated Cr-ore-fines or concentrates in the form of pellets and briquettes was to be tested. Experimentals were performed in a 70 kW and a 300 kW arc furnace. Two different slag compositions were tested. The high-MgO slag type proved suitable. The specific power consumption and the Cr-yield depend to a large extent on the type of Cr-ore and on the agglomeration process. Cr-ore pellets can be used up to 65% in the ore charge but briquettes can be used only up to 25% to replace lumpy ores without causing higher Cr-losses in the slag. (orig.) [de

  15. Concentration risk

    Directory of Open Access Journals (Sweden)

    Matić Vesna

    2016-01-01

    Full Text Available Concentration risk has been gaining a special dimension in the contemporary financial and economic environment. Financial institutions are exposed to this risk mainly in the field of lending, mostly through their credit activities and concentration of credit portfolios. This refers to the concentration of different exposures within a single risk category (credit risk, market risk, operational risk, liquidity risk.

  16. Concentrator Photovoltaics

    CERN Document Server

    Luque, Antonio L

    2007-01-01

    Photovoltaic solar-energy conversion is one of the most promising technologies for generating renewable energy, and conversion of concentrated sunlight can lead to reduced cost for solar electricity. In fact, photovoltaic conversion of concentrated sunlight insures an efficient and cost-effective sustainable power resource. This book gives an overview of all components, e.g. cells, concentrators, modules and systems, for systems of concentrator photovoltaics. The authors report on significant results related to design, technology, and applications, and also cover the fundamental physics and market considerations. Specific contributions include: theory and practice of sunlight concentrators; an overview of concentrator PV activities; a description of concentrator solar cells; design and technology of modules and systems; manufacturing aspects; and a market study.

  17. Improved design of three-dimensional lens for low concentrator PV modules; Teishukogata taiyo denchiyo sanjigen lens no koseinoka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Goma, S; Yoshioka, K; Saito, T [Tokyo Univ. of Agriculture and Technology, Tokyo (Japan)

    1997-11-25

    Attention is paid to reduction in area required for solar cells by solar concentration as a means of solving cost limits of solar cells and unstable supply of Si materials. Low concentration solar cells are effective from the aspects of utilization of scattered light and unnecessary ray tracing. The optical concentration ratio was calculated of three-dimensional lens having design values of various north/south and east/west direction allowable incidence half angles. The three-dimensional lens are designed by cutting a rectangular parallelepiped by the two-dimensional composite elliptical plane designed by various allowable incidence half angles from two directions of north/south and east/west. Using Perez`s sky solar radiation models and meteorological data HASP, calculated were the annual accumulated global radiation ratio on an inclined surface and the optical efficiency. Calculated were the solar cell area ratio and solar concentration area ratio of the concentration type to obtain solar radiation the same as that of the planar type. From the optimization calculation, it was found that lens are optimal which have design values of north/south and east/west direction allowable incidence half angles of 30-70deg. The solar cell area ratio is 57% and the solar concentration area ratio is 1.2 times. It was found that by making the module area 1.2 times, more than 40% of the solar cells used can be saved. 5 refs., 8 figs.

  18. Improved estimates of filtered total mercury loadings and total mercury concentrations of solids from potential sources to Sinclair Inlet, Kitsap County, Washington

    Science.gov (United States)

    Paulson, Anthony J.; Conn, Kathleen E.; DeWild, John F.

    2013-01-01

    Previous investigations examined sources and sinks of mercury to Sinclair Inlet based on historic and new data. This included an evaluation of mercury concentrations from various sources and mercury loadings from industrial discharges and groundwater flowing from the Bremerton naval complex to Sinclair Inlet. This report provides new data from four potential sources of mercury to Sinclair Inlet: (1) filtered and particulate total mercury concentrations of creek water during the wet season, (2) filtered and particulate total mercury releases from the Navy steam plant following changes in the water softening process and discharge operations, (3) release of mercury from soils to groundwater in two landfill areas at the Bremerton naval complex, and (4) total mercury concentrations of solids in dry dock sumps that were not affected by bias from sequential sampling. The previous estimate of the loading of filtered total mercury from Sinclair Inlet creeks was based solely on dry season samples. Concentrations of filtered total mercury in creek samples collected during wet weather were significantly higher than dry weather concentrations, which increased the estimated loading of filtered total mercury from creek basins from 27.1 to 78.1 grams per year. Changes in the concentrations and loading of filtered and particulate total mercury in the effluent of the steam plant were investigated after the water softening process was changed from ion-exchange to reverse osmosis and the discharge of stack blow-down wash began to be diverted to the municipal water-treatment plant. These changes reduced the concentrations of filtered and particulate total mercury from the steam plant of the Bremerton naval complex, which resulted in reduced loadings of filtered total mercury from 5.9 to 0.15 grams per year. Previous investigations identified three fill areas on the Bremerton naval complex, of which the western fill area is thought to be the largest source of mercury on the base

  19. Improved reproductive success in otters (Lutra lutra), grey seals (Halichoerus grypus) and sea eagles (Haliaeetus albicilla) from Sweden in relation to concentrations of organochlorine contaminants

    International Nuclear Information System (INIS)

    Roos, Anna M.; Bäcklin, Britt-Marie V.M.; Helander, Björn O.; Rigét, Frank F.; Eriksson, Ulla C.

    2012-01-01

    We studied indices of reproductive outcome in three aquatic species in relation to organochlorine concentrations during four decades. In female otters, the frequency of signs of reproduction increased after 1990. In grey seals, pregnancy rate increased 1990–2010 and uterine obstructions ceased after 1993. The frequency of uterine tumours was highest 1980–2000. The number of sea eagle nestlings per checked nest increased 1985–2000, while the frequency of desiccated eggs decreased. Organochlorine concentrations decreased at annual rates between 3.5 and 10.2%. The estimated mean concentration (mg/kg lw) for total-PCB decreased from 70 to 8 (otters), from 110 to 15 (seals) and from 955 to 275 (eagles). The corresponding concentrations for ΣDDT decreased from 3.4 to 0.2 (otters), from 192 to 2.8 (seals) and from 865 to 65 (eagles). This study adds evidence to support the hypothesis that PCBs and DDTs have had strong negative effects on the reproduction and population levels of these species. - Highlights: ► We compared trends of reproductive success in three aquatic top predators in Sweden. ► The study period covers four decades. ► Similar, increasing trends are seen from the end of the 1980s for otters, grey seals and sea eagles. ► Concentrations of total-PCB and DDTs have decreased in these species at similar rates. ► PCBs and DDTs have severely affected reproductive success in these species. - The reproductive success in otters, grey seals and white-tailed sea eagles has increased as the concentrations of PCBs and ΣDDT have decreased supporting a causative relationship.

  20. Fed batch enzymatic saccharification of food waste improves the sugar concentration in the hydrolysates and eventually the ethanol fermentation by Saccharomyces cerevisiae H058

    Directory of Open Access Journals (Sweden)

    Shoubao Yan

    2012-04-01

    Full Text Available The enzymatic hydrolysis of food waste by commercially available enzymes and the subsequent ethanol fermentation of the hydrolysates by Saccharomyces cerecisiae H058 were studied in this work. The optimum batch enzymatic conditions were found to be saccharification pH of 4.5, temperature of 55!, glucoamylase concentration of 120 u/g, α-amylase concentration of 10 u/g, solid-liquid ratio of 1: 0.75 (w/w. Fed batch hydrolysis process was started with a solid-liquid ratio of 1: 1 (w/w, with solid food waste added at time lapse of 2 h to get a final solid-liquid ratio of 1: 0.5 (w/w. After 4 h of reaction, the reducing sugar concentration reached 194.43 g/L with a enzymatic digestibility of 93.12%. Further fermentation of the batch and fed batch enzymatic hydrolysates, which contained reducing sugar concentration of 131.41 and 194.43 g/L respectively, was performed using Saccharomyces cerevisiae H058, 62.93 and 90.72 g/L ethanol was obtained within 48 h.

  1. A critical look at the calculation of the binding characteristics and concentration of iron complexing ligands in seawater with suggested improvements

    NARCIS (Netherlands)

    Gerringa, L.J.A.; Rijkenberg, M.J.A.; Thuróczy, C.-E.; Maas, L.R.M.

    2014-01-01

    Environmental context
    The low concentration of iron in the oceans limits growth of phytoplankton. Dissolved organic molecules, called ligands, naturally present in seawater, bind iron thereby increasing its solubility and, consequently, its availability for biological uptake by phytoplankton. The

  2. Moderate alcohol consumption is associated with improved insulin sensitivity, reduced basal insulin secretion rate and lower fasting glucagon concentration in healthy women

    DEFF Research Database (Denmark)

    Bonnet, F; Disse, E; Laville, M

    2012-01-01

    Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes with a stronger effect in women. As the underlying mechanisms remain poorly characterised, we investigated its relationship with insulin resistance, insulin secretion, clearance of insulin and glucagon concentration....

  3. A Plan for improving the industrial constitution in Korea for the Convention on Climate Change - concentrated on manufacturing CO{sub 2} unit analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sang In; Kim, Tae Wan; Kim, Yong Kun; Sohn, Yang Hoon; Kim, Seung Woo [Korea Environment Institute, Seoul (Korea)

    1998-12-01

    Due to the implementation of the Convention on Climate Change in future, a policy plan to prepare for the Convention on Climate Change was promoted to improve constitution of domestic economy practically including foreign negotiation strategies, national energy policy and change in consumption pattern. Based on the CO{sub 2} unit analysis in manufacturing, this study proposed an improvement plan of industrial constitution in Korea to prepare for emission trading system. 31 refs., 30 figs., 68 tabs.

  4. Concentrating Radioactivity

    Science.gov (United States)

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  5. Determination of the Optimum Concentration and Time of Salicylic Acid Foliar Application for Improving Barley Growth under Non-Saline and Saline Conditions

    Directory of Open Access Journals (Sweden)

    GH. Ranjbar

    2017-02-01

    Full Text Available In a 2yrs field study the effect of concentration and time of salicylic acid (SA foliar application on growth of barley under non-saline and saline (2 and 12 dS m-1 of NaCl, respectively conditions was evaluated in National Salinity Research Center of Iran, Yazd, central Iran during 2012-2014 growing seasons. The treatments of SA (11 treatments included without SA and SA foliar application at 0.0, 0.35, 0.70, 1.05, 1.40 and 1.75 mM applied at tillering + stem elongation + ear emergence or stem elongation + ear emergence. Salt stress led to significant decreases in seed yield and yield components; however, grain yield of barley plants were considerably increased when subjected to SA. This positive impact of SA was due probably to its effect on grain number. Average of grain yield in 0.0, 0.35, 0.70, 1.05, 1.40 and 1.75 mM SA concentrations were 496.1, 539.7, 538.5, 553.8, 517.4 and 501.3 g m-2 under non-saline and 189.2, 212.5, 219.1, 206.9, 200.3 and 182.3 g m-2 under saline conditions, respectively. Considering the negative correlation between sodium concentration in shoot and grain yield, modulating role of exogenous SA on adverse effect of salinity might be related to a SA-induced lowered Na+ concentration in such organs. The appropriate treatment seems to be SA foliar application at 1.05 mM for non-saline and 0.70 mM for saline conditions applied at stem elongation + ear emergence, as they increased grain yield by 16.6% and 18.6%, respectively. The result of this study revealed that higher concentration or frequency of SA application could be associated with negative impacts on barley.

  6. Leucine supplementation improves adiponectin and total cholesterol concentrations despite the lack of changes in adiposity or glucose homeostasis in rats previously exposed to a high-fat diet

    Directory of Open Access Journals (Sweden)

    Donato Jose

    2011-09-01

    Full Text Available Abstract Background Studies suggest that leucine supplementation (LS has a therapeutic potential to prevent obesity and to promote glucose homeostasis. Furthermore, regular physical exercise is a widely accepted strategy for body weight maintenance and also for the prevention of obesity. The aim of this study was to determine the effect of chronic LS alone or combined with endurance training (ET as potential approaches for reversing the insulin resistance and obesity induced by a high-fat diet (HFD in rats. Methods Forty-seven rats were randomly divided into two groups. Animals were fed a control diet-low fat (n = 10 or HFD (n = 37. After 15 weeks on HFD, all rats received the control diet-low fat and were randomly divided according to treatment: reference (REF, LS, ET, and LS+ET (n = 7-8 rats per group. After 6 weeks of treatment, the animals were sacrificed and body composition, fat cell volume, and serum concentrations of total cholesterol, HDL-cholesterol, triacylglycerol, glucose, adiponectin, leptin and tumor necrosis factor-alpha (TNF-α were analyzed. Results At the end of the sixth week of treatment, there was no significant difference in body weight between the REF, LS, ET and LS+ET groups. However, ET increased lean body mass in rats (P = 0.019. In addition, ET was more effective than LS in reducing adiposity (P = 0.019, serum insulin (P = 0.022 and TNF-α (P = 0.044. Conversely, LS increased serum adiponectin (P = 0.021 levels and reduced serum total cholesterol concentration (P = 0.042. Conclusions The results showed that LS had no beneficial effects on insulin sensitivity or adiposity in previously obese rats. On the other hand, LS was effective in increasing adiponectin levels and in reducing total cholesterol concentration.

  7. Improving yield and composition of protein concentrates from green tea residue in an agri-food supply chain: Effect of pre-treatment

    NARCIS (Netherlands)

    Zhang, Chen; Krimpen, Van Marinus M.; Sanders, Johan P.M.; Bruins, Marieke E.

    2016-01-01

    Rather than improving crop-production yield, developing biorefinery technology for unused biomass from the agri-food supply chain may be the crucial factor to reach sustainable global food security. A successful example of food-driven biorefinery is the extraction of protein from green tea residues,

  8. Supplementation with nanomolar concentrations of verbascoside during in vitro maturation improves embryo development by protecting the oocyte against oxidative stress: a large animal model study.

    Science.gov (United States)

    Martino, Nicola Antonio; Ariu, Federica; Bebbere, Daniela; Uranio, Manuel Filioli; Chirico, Adriana; Marzano, Giuseppina; Sardanelli, Anna Maria; Cardinali, Angela; Minervini, Fiorenza; Bogliolo, Luisa; Dell'Aquila, Maria Elena

    2016-10-01

    The effects of verbascoside (VB), added at nanomolar concentrations during in vitro maturation (IVM) of juvenile sheep oocytes, on in vitro embryo development and its mechanisms of action at the oocyte level were analyzed. Developmental rates, after IVM in the presence/absence of VB (1nM for 24h; 1nM for 2h; 10nM for 2h), were evaluated. The bioenergetic/oxidative status of oocytes matured after IVM in the presence/absence of 1nM VB for 24h was assessed by confocal analysis of mitochondria and reactive oxygen species (ROS), lipid peroxidation (LPO) assay, and quantitative PCR of bioenergy/redox-related genes. The addition of 1nM VB during 24h IVM significantly increased blastocyst formation and quality. Verbascoside reduced oocyte ROS and LPO and increased mitochondria/ROS colocalization while keeping mitochondria activity and gene expression unchanged. In conclusion, supplementation with nanomolar concentrations of VB during IVM, in the juvenile sheep model, promotes embryo development by protecting the oocyte against oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Sun-dried cowpeas and amaranth leaves recipe improves β-carotene and retinol levels in serum and hemoglobin concentration among preschool children.

    Science.gov (United States)

    Nawiri, Mildred P; Nyambaka, Hudson; Murungi, Jane I

    2013-03-01

    Vitamin A deficiency (VAD) and anemia are major challenges among children and expecting and lactating mothers in developing countries. Intervention with locally available dark green leafy vegetables (DGLV) is more sustainable to eradicate VAD, being cost-effective and readily adaptable to local communities. DGLV contain high levels of iron and β-carotene (BC) and therefore useful in fighting VAD and anemia. Since DGLVs are season-dependent sun-drying enables their availability during low seasons. However, their contribution to the bioavailability of BC and the improvement of hemoglobin are not well understood. The study therefore investigated the effect of consuming cooked recipe consisting of sun-dried amaranth and cowpea leaves on the levels of BC, retinol, and hemoglobin in preschool children from Machakos District, a semiarid region in Kenya. Vegetables were purchased from local vegetable market, with some sun-dried in an open shade. Levels of BC and retinol in serum and BC in fresh and processed vegetables were determined by a HPLC method and hemoglobin using a portable Hemocue Analyzer. All-trans-BC levels in uncooked fresh cowpea and amaranth leaves were 806.0 μg/g and 599.0 μg/g dry matter, respectively, while the dehydration and cooking processes retained the β-carotene levels at over 60 %. Consumption of the dehydrated vegetables significantly improved both serum BC and retinol levels (p < 0.05), while the baseline hemoglobin levels improved by 4.6 %. The study has shown that intervention with locally available sun-dried vegetables improves the bioavailability of BC, retinol, and hemoglobin levels among preschool children.

  10. Enhancement of encaged electron concentration by Sr(2+) doping and improvement of Gd(3+) emission through controlling encaged anions in conductive C12A7 phosphors.

    Science.gov (United States)

    Zhang, Meng; Liu, Yuxue; Zhu, Hancheng; Yan, Duanting; Yang, Jian; Zhang, Xinyang; Liu, Chunguang; Xu, Changshan

    2016-07-28

    Conductive C12A7:0.1%Gd(3+),y%Sr(2+) powders with different Sr(2+) doping concentrations have been prepared in a H2 atmosphere by a solid state method in combination with subsequent UV-irradiation. The encaged electron concentration could be modulated through tuning Sr(2+) doping and its maximum value reaches 2.3 × 10(19) cm(-3). This is attributed to the competition between enhanced uptake and the release of the encaged anions during their formation and diffusion processes and the suppression of encaged electrons generation due to the increased encaged OH(-) anions and the decreased encaged O(2-) anions. Although there exists encaged electrons and different encaged anions (O(2-), H(-) and OH(-)) in C12A7 conductive powders prepared through the hydrogen route, a dominant local environment around Gd(3+) could be observed using electron spin resonance (ESR) detection. It can be ascribed to the stronger coupling of the encaged OH(-) to the framework of C12A7 than those of the encaged electrons, O(2-) and H(-) anions. In addition, emission of Gd(3+) ions is enhanced under UV or low voltage electron beam excitation and a new local environment around Gd(3+) ions appears through the thermal annealing in air because of the decrease of the encaged OH(-) anions and the increase of the encaged O(2-) anions. Our results suggested that Sr(2+) doping in combination with thermal annealing in air is an effective strategy for increasing the conductive performance and enhancing the emission of rare earth ions doped into C12A7 conductive phosphors for low-voltage field emission displays (FEDs).

  11. Improved lithium cyclability and storage in mesoporous SnO2 electronically wired with very low concentrations (≤1 %) of reduced graphene oxide.

    Science.gov (United States)

    Shiva, Konda; Rajendra, H B; Subrahmanyam, K S; Bhattacharyya, Aninda J; Rao, C N R

    2012-04-10

    On the wire: Mesoporous tin dioxide (SnO(2)) wired with very low amounts (≤1 %) of reduced graphene oxide (rGO) exhibits a remarkable improvement in lithium-ion battery performance over bare mesoporous or solid nanoparticles of SnO(2). Reversible lithium intercalation into SnO(2)/SnO over several cycles was demonstrated in addition to conventional reversible lithium storage by an alloying reaction. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Concentrado proteico do soro melhora a qualidade sensorial de sobremesa láctea diet Whey protein concentrate improves the sensory quality of free-fat dairy desserts

    Directory of Open Access Journals (Sweden)

    Márcia Cristina Teixeira Ribeiro Vidigal

    2012-12-01

    Full Text Available Alimentos isentos ou de baixo nível de gordura constituem um desafio para a indústria de alimentos. Nesse contexto, este trabalho teve como objetivo estudar o efeito da adição de concentrado proteico de soro (CPS nas características sensoriais e aceitabilidade de sobremesas lácteas sem gordura. Quatro formulações foram desenvolvidas com diferentes concentrações de CPS (0%, 1,5%, 3,0% e 4,5% m v-1 e caracterizadas sensorialmente por meio da Análise Descritiva. A aceitabilidade das formulações foi avaliada por 94 consumidores que utilizaram escala hedônica de nove pontos. As sobremesas foram caracterizadas por oito atributos sensoriais: cor, firmeza, resistência ao corte, brilho, consistência, gomosidade, aroma e sabor de baunilha. As formulações contendo 3,0 e 4,5% de CPS apresentaram maior intensidade de todos os atributos sensoriais. A adição de CPS foi efetiva na composição da textura das sobremesas lácteas diet, além de realçar a cor, sabor e aroma do produto. As formulações contendo 1,5 e 3,0% de CPS foram as mais aceitas, evidenciando que a utilização do CPS nessas concentrações favoreceu a aceitabilidade do produto, proporcionando características sensoriais agradáveis aos consumidores.Foods free or low-fat constituted are a challenge for the food industry. Thus, the objective of this research was to study the effect of the addition of whey protein concentrate (WPC in the sensory profile and acceptability of dairy desserts free-fat. Four formulations had been developed with different WPC concentrations (0%, 1.5%, 3.0% or 4.5%, mass% and sensory characterized by Descriptive Analysis. The acceptability of the formulations was evaluated by 94 consumers who had used the nine-point hedonic scale. Dairy desserts were characterized by eight sensory attributes: color, firmness, resistance to cut, brightness, thickness, gumminess, aroma and vanilla flavor. The formulations containing 3.0 and 4.5% of WPC presented

  13. A combination of grapefruit seed extract and concentrated cranberry juice as a potential antimicrobial preservative for the improvement of microbiological stability of hypromellose gel.

    Science.gov (United States)

    Bernatoniene, Jurga; Keraitė, Rasa; Masteiková, Ruta; Pavilonis, Alvydas; Savickas, Arūnas

    2013-10-01

    Aqueous hypromellose gels are not microbiologically stable - they show signs of microorganism growth during storage. To extend the shelf-life of the gels, antimicrobial preservatives are needed. Some substances of plant origin are known for their antimicrobial properties, and thus they may be used as an alternative to synthetic preservatives. Therefore, the aim of this study was to evaluate the microbiological stability of aqueous hypromellose gel and the effectiveness of natural substances - grapefruit seed extract (GSE), concentrated cranberry juice, and a combination thereof - on the antimicrobial protection of the gel. The evaluation of the antimicrobial activity of GSE and cranberry juice showed that their antimicrobial effects differed. Both cranberry juice and GSE inhibited the growth of the standard gram-positive and gram-negative bacteria, but the effect of GSE was significantly stronger. Candida albicans was sensitive only to GSE. For this reason, in order to affect all the microorganisms studied, either a combination of 0.7% GSE and 10% cranberry juice, or 5% GSE alone may be used. The combination of GSE and cranberry juice was effective only in acidic medium (pH being 2.5-5), while the antimicrobial effect of GSE was not dependent on the pH value.

  14. Supplementation of different concentrations of Orvus Es Paste (OEP) to ostrich egg yolk lipoprotein extender improves post-thaw boar semen quality.

    Science.gov (United States)

    Fraser, L; Jasiewicz, E; Kordan, W

    2014-01-01

    This study aimed to compare post-thaw quality of boar semen following freezing in an ostrich egg yolk lipoprotein (LPFo) extender supplemented with 0%, 0.25% and 0.50% Orvus Es Paste (OEP). Sperm assessments included total motility (TMOT), mitochondrial function (MF), plasma membrane integrity (PMI) and acrosome integrity (normal apical ridge, NAR). Considerable variations among boars and OEP treatments had a significant effect (P semen samples frozen in the absence of OEP. By contrast, lactose-LPFo-glycerol extender supplemented with either 0.25% OEP or 0.50% OEP markedly enhanced post-thaw sperm characteristics. In all boars, there were no marked differences in post-thaw sperm TMOT between the freezing extenders supplemented with 0.25% and 0.50% OEP. However, a decline in the percentage of post-thaw motile spermatozoa was more pronounced in the extender supplemented with 0.50% OEP following a 120-min incubation period. Furthermore, the proportions of frozen-thawed spermatozoa with MF, PMI and NAR acrosomes varied significantly among the boars in the OEP-supplemented extenders. The findings of this study indicate that different OEP concentrations, in the presence of ostrich egg yolk lipoproteins, could have varying effects on post-thaw sperm survival.

  15. Evaluating the effect of administrating hypertonic and isotonic saline solutions on clinical improvement, serum electrolyte concentrations and renal function of calves affected by diarrhea

    Directory of Open Access Journals (Sweden)

    A Hasanpour

    2009-11-01

    This study was conducted on 40 calves under the age of one mouth with 30 calves affected by diarrhea allocated to 3 treatment groups of 10 calves each and the control group consisting of 10 calves. The control group received neither treatment nor any injections. In the first treatment group, only antibiotics were administered without any fluid therapy. In the second treatment group, apart from antibiotic therapy of diarrhea, hypertonic saline solution (7.5% was administered at a dose of 5 ml/kg as slow intravenous infusion alongside oral ORS solution whereas in the third treatment group isotonic saline solution (0.9% was given intravenously according to the formula (Body weight × %Dehydration alongside oral ORS solution. In all groups, clinical examination and blood sampling was undertaken at times 0, 1, 2, 8 and 24 hours following treatment. At time 0, the diarrhea had resulted in clinical and laboratory signs such as a fever, the dehydration, tachycardia, oligopnea, increased packed sell volume, hypernatremia, hyperchloremia, hyperkalemia, hyperphosphatemia, hypercalcemia, increased serum creatinine and BUN values. Following treatment, fever subsided and the dehydration was corrected and this correction occurred faster in calves which had received hypertonic saline solution. Correction of sodium, potassium, chloride, phosphorus and calsium imbalance occurred faster in patients which were treated by hypertonic solution. Fluid therapy with saline solutions prevented the increase in serum creatinine and BUN values. In conclusion, the administration of hypertonic saline solutions leads to much faster and more reliable clinical improvement and electrolyte imbalance correction in calves affected by diarrhea.

  16. Temperature dependence of the short-range order parameter and the concentration dependence of the order disorder temperature for Ni-Pt and Ni-Fe systems in the improved statistical pseudopotential approximation

    International Nuclear Information System (INIS)

    Khwaja, F.A.

    1980-08-01

    The calculations for the temperature dependence of the first shell short-range order (SRO) parameter for Ni 3 Fe using the cubic approximation of Tahir Kheli, and the concentration dependence of order-disorder temperature Tsub(c) for Ni-Fe and Ni-Pt systems using the linear approximation, have been carried out in the framework of pseudopotential theory. It is shown that the cubic approximation yields a good agreement between the theoretical prediction of the α 1 and the experimental data. Results for the concentration dependence of the Tsub(c) show that improvements in the statistical pseudo-potential approach are essential to achieve a good agreement with experiment. (author)

  17. A novel self-micro-emulsifying delivery system (SMEDS) formulation significantly improves the fasting absorption of EPA and DHA from a single dose of an omega-3 ethyl ester concentrate.

    Science.gov (United States)

    Qin, Yan; Nyheim, Hilde; Haram, Else Marie; Moritz, Joseph M; Hustvedt, Svein Olaf

    2017-10-16

    Absorption of EPA and DHA from Omega-3-acid ethyl ester (EE) concentrate supplements occurs most efficiently when taken in context of a fatty meal; adequate fat intake is required to release bile salts that emulsify and pancreatic enzymes that digest omega-3-containing lipids in the intestine. Current guidelines recommend reduction in fat intake and therefore there is a need to optimize the absorption of Omega-3 in those consuming low-fat or no-fat meals. To this end, BASF has developed an Absorption Acceleration Technology, a novel self-micro-emulsifying delivery system (SMEDS) formulation of highly concentrated Omega-3-acid EE which enables rapid emulsification and microdroplet formation upon entering the aqueous environment of the gut therefore enhances the absorption. Two separate single dose, crossover studies were conducted to determine the relative bioavailability of omega-3-acid EE concentrate, either as a novel SMEDS formulation (PRF-021) or as control, in healthy fasted male and female adults at two dose levels (Study 1 "low dose": 630 mg EPA + DHA in PRF-021 vs. 840 mg EPA + DHA in control; Study 2 "high dose": 1680 mg EPA + DHA in PRF-021 vs. 3360 mg EPA + DHA in control). Blood samples were collected immediately before supplementation and at defined time intervals for 48 h. Plasma concentration of total EPA and DHA were determined for pharmacokinetic analysis, area under the curve (AUC) and maximum observed concentration (C max ) was determined. Total EPA plus DHA absorption from SMEDS formulation PRF-021 were 6.4 and 11.5 times higher compared to control in low- and high-dose studies respectively, determined as the ratio of baseline corrected, dose normalized AUC 0-24h of PRF-021 over that of control. EPA and DHA individually showed differing levels of enhancement: the AUC 0-24h ratio for EPA was 23.8 and 25.7 in low and high dose studies, respectively, and the AUC 0-24h ratio for DHA was 3.6 and 5.6 in low and high dose studies

  18. Parabolic solar concentrator

    Science.gov (United States)

    Tecpoyotl-Torres, M.; Campos-Alvarez, J.; Tellez-Alanis, F.; Sánchez-Mondragón, J.

    2006-08-01

    In this work we present the basis of the solar concentrator design, which has is located at Temixco, Morelos, Mexico. For this purpose, this place is ideal due to its geographic and climatic conditions, and in addition, because it accounts with the greatest constant illumination in Mexico. For the construction of the concentrator we use a recycled parabolic plate of a telecommunications satellite dish (NEC). This plate was totally covered with Aluminum. The opening diameter is of 332 cm, the focal length is of 83 cm and the opening angle is of 90°. The geometry of the plate guaranties that the incident beams, will be collected at the focus. The mechanical treatment of the plate produces an average reflectance of 75% in the visible region of the solar spectrum, and of 92% for wavelengths up to 3μm in the infrared region. We obtain up to 2000°C of temperature concentration with this setup. The reflectance can be greatly improved, but did not consider it as typical practical use. The energy obtained can be applied to conditions that require of those high calorific energies. In order to optimize the operation of the concentrator we use a control circuit designed to track the apparent sun position.

  19. Tritium concentration monitor

    International Nuclear Information System (INIS)

    Shono, Kosuke.

    1991-01-01

    A device for measuring the concentration of tritium in gaseous wastes in a power plant and a nuclear fuel reprocessing plant is reduced in the size and improved in performance. The device of the present invention pressurizes a sampling gas and cools it to a dew point. Water content in the sampling gas cooled to the dew point is condensated and recovered to a fine tube-like water content recovering container. The concentration of the recovered condensates is measured by a tritium density analyzer. With such procedures, since the specimen is pressurized, the dew point can be elevated. Accordingly, the size of the cooling device can be decreased, enabling to contribute to the reduction of the size of the entire device. Further, since the water content recovering device is formed as a fine tube, the area of contact between the specimen gas and the liquid condensated water can be reduced. Accordingly, evaporation of the liquid condensates can be prevented. (I.S.)

  20. Would Be Prophylactic Administrations of Low Concentration of Alendronate an Alternative for Improving the Craniofacial Bone Repair? A Preliminary Study Focused in the Period of Cellular Differentiation and Tissue Organization.

    Science.gov (United States)

    Göhringer, Isabella; Muller, Carmem L Storrer; Cunha, Emanuelle Juliana; Passoni, Giuliene Nunes De Souza; Vieira, Juliana Souza; Zielak, João Cesar; Scariot, Rafaela; Deliberador, Tatiana Miranda; Giovanini, Allan Fernando

    2017-10-01

    Alendronate (ALN) is a nitrogen-bisphosphonate that may induce an anabolic effect on craniofacial bone repair when administrated in low doses. Based on this premise, this study analyzed the influence of prophylactic low doses of ALN on bone healing in defects created in rabbit mandible. A 5 × 2-mm diameter deep defect was created in the calvaria of 28 rabbits. Fourteen of these rabbits received previously 50 μg/kg of 1% sodium ALN for 4 weeks, while the other rabbits received only 0.9% physiological saline solution (control). Animals were euthanized at 15 and 60 days postsurgery (n = 7), and the data were analyzed using histomorphometry and immunohistochemistry using the anti-CD34, bone morphogenetic protein -2 (BMP-2), and transforming growth factor (TGF)-β1 antibodies. On the 15th day postsurgery, the specimens that received previous treatment with ALN demonstrated large vascular lumen and intense positivity to CD34 either concentrated in endothelium or cells spread among the reparative tissue. These results coincided with intense positivity for BMP-2+ cells and TGF-β1 that was concentrated in both cells and perivascular area. In contrast, the control group revealed scarce cells that exhibited CD34, BMP-2+, and the TGF-β1 was restricted for perivascular area on well-formed granulation tissue. These patterns of immunohistochemical result, especially found on the 15th day of analysis, seem to be responsible for the development of larger quantities of bone matrix in the specimens that receive ALN on the 60th day postsurgery. These preliminary results showed that the prophylactic administration of low doses of ALN might be an alternative to craniofacial bone craniofacial bone repair because it increases the immunopositivity for TGF-β1 and consequently improves the CD34+ and BMP-2+ cells on reparative sites.

  1. Limited Weight Loss or Simply No Weight Gain following Lifestyle-Only Intervention Tends to Redistribute Body Fat, to Decrease Lipid Concentrations, and to Improve Parameters of Insulin Sensitivity in Obese Children

    Directory of Open Access Journals (Sweden)

    Valeri Lenin

    2011-03-01

    Full Text Available Objectives. To investigate whether lifestyle-only intervention in obese children who maintain or lose a modest amount of weight redistributes parameters of body composition and reverses metabolic abnormalities. Study Design. Clinical, anthropometric, and metabolic parameters were assessed in 111 overweight or obese children (CA of 11.3 ± 2.8 years; 63 females and 48 males, during 8 months of lifestyle intervention. Patients maintained or lost weight (1–5% (group A; n: 72 or gained weight (group B. Results. Group A patients presented with a decrease in systolic blood pressure (SBP and diastolic blood pressure (DBP ( and , resp., BMI (, z-score BMI (, waist circumference (, fat mass (, LDL-C (, Tg/HDL-C ratio (, fasting and postprandial insulin (, and HOMA (, while HDL-C ( and QUICKI increased (. Conversely, group B patients had an increase in BMI (, waist circumference (, SBP (, and in QUICKI (, while fat mass (, fasting insulin (, and HOMA ( decreased. Lean mass, DBP, lipid concentrations, fasting and postprandial glucose, postprandial insulin, and ultrasensitive C-reactive protein (CRP remained stable. Conclusions. Obese children who maintain or lose a modest amount of weight following lifestyle-only intervention tend to redistribute their body fat, decrease blood pressure and lipid levels, and to improve parameters of insulin sensitivity.

  2. Scattering Solar Thermal Concentrators

    Energy Technology Data Exchange (ETDEWEB)

    Giebink, Noel C. [Pennsylvania State Univ., State College, PA (United States)

    2015-01-31

    This program set out to explore a scattering-based approach to concentrate sunlight with the aim of improving collector field reliability and of eliminating wind loading and gross mechanical movement through the use of a stationary collection optic. The approach is based on scattering sunlight from the focal point of a fixed collection optic into the confined modes of a sliding planar waveguide, where it is transported to stationary tubular heat transfer elements located at the edges. Optical design for the first stage of solar concentration, which entails focusing sunlight within a plane over a wide range of incidence angles (>120 degree full field of view) at fixed tilt, led to the development of a new, folded-path collection optic that dramatically out-performs the current state-of-the-art in scattering concentration. Rigorous optical simulation and experimental testing of this collection optic have validated its performance. In the course of this work, we also identified an opportunity for concentrating photovoltaics involving the use of high efficiency microcells made in collaboration with partners at the University of Illinois. This opportunity exploited the same collection optic design as used for the scattering solar thermal concentrator and was therefore pursued in parallel. This system was experimentally demonstrated to achieve >200x optical concentration with >70% optical efficiency over a full day by tracking with <1 cm of lateral movement at fixed latitude tilt. The entire scattering concentrator waveguide optical system has been simulated, tested, and assembled at small scale to verify ray tracing models. These models were subsequently used to predict the full system optical performance at larger, deployment scale ranging up to >1 meter aperture width. Simulations at an aperture widths less than approximately 0.5 m with geometric gains ~100x predict an overall optical efficiency in the range 60-70% for angles up to 50 degrees from normal. However, the

  3. Ownership concentration and bank profitability

    Directory of Open Access Journals (Sweden)

    Peterson Kitakogelu Ozili

    2017-12-01

    Full Text Available We investigate whether ownership concentration influences bank profitability in a developing country context. We focus on bank ownership concentration measured as the amount of direct equity held by a majority shareholder categorised into: high ownership concentration, moderate ownership concentration and disperse ownership. We find that banks with high ownership concentration have higher return on assets, higher net interest margin and higher recurring earning power while banks with dispersed ownership have lower return on assets but have higher return on equity. Also, higher cost efficiency improves the return on assets of widely-held banks and the return on equity of banks with moderate ownership. The findings have implications. JEL: Code: G3, G34, G31, Keywords: Corporate governance, Ownership structure, Agency theory, Profitability, Firm performance, Banks, Return on asset, Return on equity

  4. A single dose of a neuron-binding human monoclonal antibody improves brainstem NAA concentrations, a biomarker for density of spinal cord axons, in a model of progressive multiple sclerosis.

    Science.gov (United States)

    Wootla, Bharath; Denic, Aleksandar; Watzlawik, Jens O; Warrington, Arthur E; Rodriguez, Moses

    2015-04-29

    Intracerebral infection of susceptible mouse strains with Theiler's murine encephalomyelitis virus (TMEV) results in chronic demyelinating disease with progressive axonal loss and neurologic dysfunction similar to progressive forms of multiple sclerosis (MS). We previously showed that as the disease progresses, a marked decrease in brainstem N-acetyl aspartate (NAA; metabolite associated with neuronal integrity) concentrations, reflecting axon health, is measured. We also demonstrated stimulation of neurite outgrowth by a neuron-binding natural human antibody, IgM12. Treatment with either the serum-derived or recombinant human immunoglobulin M 12 (HIgM12) preserved functional motor activity in the TMEV model. In this study, we examined IgM-mediated changes in brainstem NAA concentrations and central nervous system (CNS) pathology. (1)H-magnetic resonance spectroscopy (MRS) showed that treatment with HIgM12 significantly increased brainstem NAA concentrations compared to controls in TMEV-infected mice. Pathologic analysis demonstrated a significant preservation of axons in the spinal cord of animals treated with HIgM12. This study links drug efficacy of slowing deficits with axon preservation and NAA concentrations in the brainstem in a model of progressive MS. HIgM12-mediated changes of NAA concentrations in the brainstem are a surrogate marker of axon injury/preservation throughout the spinal cord. This study provides proof-of-concept that a neuron-reactive human IgM can be therapeutic and provides a biomarker for clinical trials.

  5. Current Status of Concentrator Photovoltaic (CPV) Technology

    Energy Technology Data Exchange (ETDEWEB)

    Philipps, Simon P. [Fraunhofer Inst. for Solar Energy Systems ISE, Freiburg (Germany); Bett, Andreas W. [Fraunhofer Inst. for Solar Energy Systems ISE, Freiburg (Germany); Horowitz, Kelsey [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kurtz, Sarah [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-12-01

    This report summarizes the status of the concentrator photovoltaic (CPV) market and industry as well as current trends in research and technology. This report is intended to guide research agendas for Fraunhofer ISE, the National Renewable Energy Laboratory (NREL), and other R&D organizations. Version 1.1 of this report includes recent progress in CPV. The recent record module efficiency of 38.9% at Concentrator Standard Test Conditions (CSTC) is an impressive result, demonstrating the continuing opportunity for CPV technology to improve. 38.9% at Concentrator Standard Test Conditions (CSTC) is an impressive result, demonstrating the continuing opportunity for CPV technology to improve. 38.9% at Concentrator Standard Test Conditions (CSTC) is an impressive result, demonstrating the continuing opportunity for CPV technology to improve. 38.9% at Concentrator Standard Test Conditions (CSTC) is an impressive result, demonstrating the continuing opportunity for CPV technology to improve.

  6. Ultra flat ideal concentrators of high concentration

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Julio [IST, Physics Dept., Lisboa (Portugal); INETI-DER, Lisboa (Portugal); Collares-Pereira, Manuel [INETI-DER, Lisboa (Portugal)

    2000-07-01

    A new method for the design of nonimaging devices is presented. Its application to the design of ultra flat compact concentrators is analysed. These new concentrators are based on a combination of two stages: the first one is composed of a large number of small structures placed side by side and the second one is a very compact single device concentrating the radiation to the limit. These devices are ideal for 2D. These compact designs are much more compact than the traditional ones like lens-mirror combinations or parabolic primaries with nonimaging secondaries. Besides, they can be designed for any acceptance angle, while the traditional ones are limited to small acceptance angles. (Author)

  7. Highly concentrating Fresnel lenses

    International Nuclear Information System (INIS)

    Kritchman, E.M.; Friesem, A.A.; Yekutieli, G.

    1979-01-01

    A new type of concave Fresnel lens capable of concentrating solar radiation very near the ultimate concentration limit is considered. The differential equations that describe the lens are solved to provide computed solutions which are then checked by ray tracing techniques. The performance (efficiency and concentration) of the lens is investigated and compared to that of a flat Fresnel lens, showing that the new lens is preferable for concentrating solar radiation. (author)

  8. Solar cell concentrating system

    International Nuclear Information System (INIS)

    Garg, H.P.; Sharma, V.K.; Agarwal, R.K.

    1986-11-01

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  9. Rheology of concentrated biomass

    Science.gov (United States)

    J.R. Samaniuk; J. Wang; T.W. Root; C.T. Scott; D.J. Klingenberg

    2011-01-01

    Economic processing of lignocellulosic biomass requires handling the biomass at high solids concentration. This creates challenges because concentrated biomass behaves as a Bingham-like material with large yield stresses. Here we employ torque rheometry to measure the rheological properties of concentrated lignocellulosic biomass (corn stover). Yield stresses obtained...

  10. Theoretical modelling of solar dish concentrator

    International Nuclear Information System (INIS)

    Yaaseen Rafeeu; Mohd Zainal Abidin Abdul Kadir; Senan Mohamed Abdulla; Nor Mariah Adam

    2009-01-01

    Full text: Concentrating solar power (CSP) technologies could be one of the major contributor to worlds future energy needs and which would be cheap and clean sources of energy. This would improve energy utilization, higher conversion efficiency with reliable and affordable supply of electricity to the public. The proposed approach is using different size and depth of solar dish concentrators to improve solar fraction using the aluminium foil as reflector. In this paper, different measurement of solar concentrators is investigated and aims to aims to introducing an improved methodology for solar fraction on incoming solar energy in wet climate. (author)

  11. Critical heat flux in bottom heated two-phase thermosyphon. Improvement in critical heat flux due to concentric tube; Katan shuchu kanetsugata niso netsu syphon no genkai netsu ryusoku. Nijukan ni yoru genkai netsu ryusoku no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Monde, M.; Mitsutake, Y. [Saga University, Saga (Japan). Faculty of Science and Engineering

    2000-02-25

    An experiment has been carried out to elucidate the critical heat flux (CHF) of an open two-phase thermosyphon with a bottom heated chamber in which heat is absorbed by evaporation of liquid. Another objective is to enhance the CHF using a concentric-tube by which counter-current flow of vapor and liquid in the throat of the chamber can be controlled well. The CHF data are measured for the saturated liquid of R 113 at a different pressure and different configuration of concentric tubes. The CHF data without the inner tube are in good agreement with the existing correlation and analytical result. The CHF increases by as much as several times of the CHF without the inner tube with an increase in the inner tube diameter up to a certain diameter of the inner tube and then decreases continuously as the inner tube diameter approaches the outer tube diameter. The optimum diameter of inner tube exists at which the CHF is maximum. (author)

  12. Recalculation of measured fuel nuclide concentrations

    International Nuclear Information System (INIS)

    Moeller, W.

    1984-01-01

    The concentrations and concentration ratios of heavy fuel nuclides determined in the Central Institute for Nuclear Research Rossendorf on the basis of destructive burnup measurements are compared with the results of microburnup calculations. The possibility is discussed to improve the results by taking into account the spectral characteristics at the positions of the measuring samples. (author)

  13. Improving Photosynthesis

    Science.gov (United States)

    Evans, John R.

    2013-01-01

    Photosynthesis is the basis of plant growth, and improving photosynthesis can contribute toward greater food security in the coming decades as world population increases. Multiple targets have been identified that could be manipulated to increase crop photosynthesis. The most important target is Rubisco because it catalyses both carboxylation and oxygenation reactions and the majority of responses of photosynthesis to light, CO2, and temperature are reflected in its kinetic properties. Oxygenase activity can be reduced either by concentrating CO2 around Rubisco or by modifying the kinetic properties of Rubisco. The C4 photosynthetic pathway is a CO2-concentrating mechanism that generally enables C4 plants to achieve greater efficiency in their use of light, nitrogen, and water than C3 plants. To capitalize on these advantages, attempts have been made to engineer the C4 pathway into C3 rice (Oryza sativa). A simpler approach is to transfer bicarbonate transporters from cyanobacteria into chloroplasts and prevent CO2 leakage. Recent technological breakthroughs now allow higher plant Rubisco to be engineered and assembled successfully in planta. Novel amino acid sequences can be introduced that have been impossible to reach via normal evolution, potentially enlarging the range of kinetic properties and breaking free from the constraints associated with covariation that have been observed between certain kinetic parameters. Capturing the promise of improved photosynthesis in greater yield potential will require continued efforts to improve carbon allocation within the plant as well as to maintain grain quality and resistance to disease and lodging. PMID:23812345

  14. Underscreening in concentrated electrolytes.

    Science.gov (United States)

    Lee, Alpha A; Perez-Martinez, Carla S; Smith, Alexander M; Perkin, Susan

    2017-07-01

    Screening of a surface charge by an electrolyte and the resulting interaction energy between charged objects is of fundamental importance in scenarios from bio-molecular interactions to energy storage. The conventional wisdom is that the interaction energy decays exponentially with object separation and the decay length is a decreasing function of ion concentration; the interaction is thus negligible in a concentrated electrolyte. Contrary to this conventional wisdom, we have shown by surface force measurements that the decay length is an increasing function of ion concentration and Bjerrum length for concentrated electrolytes. In this paper we report surface force measurements to test directly the scaling of the screening length with Bjerrum length. Furthermore, we identify a relationship between the concentration dependence of this screening length and empirical measurements of activity coefficient and differential capacitance. The dependence of the screening length on the ion concentration and the Bjerrum length can be explained by a simple scaling conjecture based on the physical intuition that solvent molecules, rather than ions, are charge carriers in a concentrated electrolyte.

  15. Concentrating photovoltaic solar panel

    Science.gov (United States)

    Cashion, Steven A; Bowser, Michael R; Farrelly, Mark B; Hines, Braden E; Holmes, Howard C; Johnson, Jr., Richard L; Russell, Richard J; Turk, Michael F

    2014-04-15

    The present invention relates to photovoltaic power systems, photovoltaic concentrator modules, and related methods. In particular, the present invention features concentrator modules having interior points of attachment for an articulating mechanism and/or an articulating mechanism that has a unique arrangement of chassis members so as to isolate bending, etc. from being transferred among the chassis members. The present invention also features adjustable solar panel mounting features and/or mounting features with two or more degrees of freedom. The present invention also features a mechanical fastener for secondary optics in a concentrator module.

  16. Photovoltaic static concentrator analysis

    Science.gov (United States)

    Almonacid, G.; Luque, A.; Molledo, A. G.

    1984-12-01

    Ray tracing is the basis of the present analysis of truncated bifacial compound parabolic concentrators filled with a dielectric substance, which are of interest in photovoltaic applications where the bifacial cells allow higher static concentrations to be achieved. Among the figures of merit for this type of concentrator, the directional intercept factor plays a major role and is defined as the ratio of the power of the collector to that at the entry aperture, in a lossless concentrator illuminated by light arriving from a given direction. A procedure for measuring outdoor, full size panels has been developed, and a correction method for avoiding the effect of unwanted diffuse radiation during the measurements is presented.

  17. CMAQ predicted concentration files

    Data.gov (United States)

    U.S. Environmental Protection Agency — model predicted concentrations. This dataset is associated with the following publication: Muñiz-Unamunzaga, M., R. Borge, G. Sarwar, B. Gantt, D. de la Paz, C....

  18. Vaginal oxytetracycline concentrations.

    Science.gov (United States)

    Thin, R N; Al Rawi, Z H; Simmons, P D; Treharne, J; Tabaqchali, S

    1979-01-01

    Although tetracycline preparations are widely used in departments of genitourinary medicine, or sexually transmitted diseases clinics, little is known of the concentrations of these preparations in genital secretions. For this reason a microbiological method was used for estimating oxytetracycline concentrations in vaginal secretions. These concentrations varied from 0.6 to 6.5 microgram/ml in 19 women who had had sexual contact with a man with non-specific urethritis and who were taking oxytetracycline dihydrate 250 mg four times daily. They were well in excess of the minimum inhibitory concentration of oxytetracycline (0.2 microgram/ml) for the strains of Chlamydia trachomatis isolated from the patients with positive culture results. Thus, oxytetracycline 250 mg four times daily appears to be a satisfactory regimen for the treatment of chlamydial genital infection in women. PMID:509190

  19. Concentrations of Indicator Organisms

    Data.gov (United States)

    U.S. Environmental Protection Agency — It is a compilation of organism concentrations of 16 sampling events conducted between July 2015 and February 2016. It also includes statistical analysis such as...

  20. Concentrated Differential Privacy

    OpenAIRE

    Dwork, Cynthia; Rothblum, Guy N.

    2016-01-01

    We introduce Concentrated Differential Privacy, a relaxation of Differential Privacy enjoying better accuracy than both pure differential privacy and its popular "(epsilon,delta)" relaxation without compromising on cumulative privacy loss over multiple computations.

  1. Industrialisation et concentration urbaine

    OpenAIRE

    Kamal , Abdelhak

    2010-01-01

    The aim of this thesis is to analyze the determinants of the urban concentration and their effect at different levels of development. The empirical analysis focuses on the developing countries over the period 1950-2000 grouped by level of per capita income. The results confirm the existence of specific trajectories of urbanization rate and urban primacy which differs meaningfully according to the stage of development considered. Certain factors encourage urbanization and its concentration in ...

  2. Solar concentrators. Concentradores solares

    Energy Technology Data Exchange (ETDEWEB)

    Almanza, R.; Valdes, A.; Lopez, S.

    1981-06-01

    This paper presents different types of geometries used in concentrators. Some comments are made on the theoretical and experimental analysis necessary to evaluate the geometries and on the type of laboratory equipment needed to obtain experimental data. At the end of the report a description of how to build parabolic trough mirrors is made. The experience gained by the authors, who have been working in this subject for the past five years, is summarized, showing some of the problems related with such concentrators.

  3. Concentration factors for fish

    International Nuclear Information System (INIS)

    Feldt, W.; Lauer, R.; Melzer, M.; Siebert, W.

    1978-01-01

    Concentration factors are defined as operators allowing to calculate the specific activity of fish meat from a given concentration of an element in the water. This parameter depends among others from the content of stable isotopes and homologues in the different waters. If this parameter is reasonably to be used for model calculations it must be referred to water with all of its content substances, these calculations also being based on this type of 'water'. (orig.) [de

  4. FK concentrator outdoor measurements

    OpenAIRE

    Hernández Sanz, Maikel; Vilaplana, J., J.; Benitez Gimenez, Pablo; Mohedano,, Rubén; Zamora Herranz, Pablo; Miñano Dominguez, Juan Carlos; Mendes Lopes, Joao

    2013-01-01

    The FK is a two-stage optical concentrator for CPV, composed by a Fresnel lens working as POE and a refractive element working as SOE. Both elements perform Köhler integration, for uniform irradiance purposes. The FK has demonstrated that compares very well with other Fresnel-based concentrator optics. Recent on-sun measurements carried out on an FK mono-module prototype have already shown outstanding results, achieving electrical efficiencies over 34%. Further optimization of optical design ...

  5. Metformin affects macrophages' phenotype and improves the activity of glutathione peroxidase, superoxide dismutase, catalase and decreases malondialdehyde concentration in a partially AMPK-independent manner in LPS-stimulated human monocytes/macrophages.

    Science.gov (United States)

    Bułdak, Łukasz; Łabuzek, Krzysztof; Bułdak, Rafał Jakub; Kozłowski, Michał; Machnik, Grzegorz; Liber, Sebastian; Suchy, Dariusz; Duława-Bułdak, Anna; Okopień, Bogusław

    2014-06-01

    Diabetic patients experience accelerated atherosclerosis. Metformin is a cornerstone of the current therapy of type 2 diabetes. Macrophages are the key cells associated with the development of atherosclerotic plaques. Therefore, our aim was to assess the in vitro effects of metformin on macrophages and its influence on the mechanisms involved in the development of atherosclerosis. Peripheral blood mononuclear cells were obtained from the group including 16 age-matched healthy non-smoking volunteers aged 18-40 years. Monocytes were further incubated with metformin, LPS and compound C--a pharmacological inhibitor of AMPK. The impact of metformin on oxidative stress markers, antioxidative properties, inflammatory cytokines and phenotypical markers of macrophages was studied. We showed that macrophages treated with metformin expressed less reactive oxygen species (ROS), which resulted from increased antioxidative potential. Furthermore, a reduction in inflammatory cytokines was observed. We also observed a phenotypic shift toward the alternative activation of macrophages that was induced by metformin. All the aforementioned results resulted from AMPK activation, but a residual activity of metformin after AMPK blockade was still noticeable even after inhibition of AMPK by compound C. Authors believe that metformin-based therapy, a cornerstone in diabetes therapy, not only improves the prognosis of diabetics by reducing blood glucose but also by reducing oxidative stress, inflammatory cytokine production and the shift toward alternative activation of macrophages. Copyright © 2014 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  6. High-flux solar concentration with imaging designs

    Energy Technology Data Exchange (ETDEWEB)

    Feuermann, D. [Ben-Gurion University of the Negev (Israel). Jacob Blaustein Institute for Desert Research; Gordon, J.M. [Ben-Gurion University of the Negev (Israel). Jacob Blaustein Institute for Desert Research; Ben-Gurion University of the Negev (Israel). Dept. of Mechanical Engineering; Ries, H. [Ries and Partners, Munich (Germany)

    1999-02-01

    Most large solar concentrators designed for high flux concentration at high collection efficiency are based on imaging primary mirrors and nonimaging secondary concentrators. In this paper, we offer an alternative purely imaging two-stage solar concentrator that can attain high flux concentration at high collection efficiency. Possible practical virtues include: (1) an inherent large gap between absorber and secondary mirror; (2) a restricted angular range on the absorber; and (3) an upward-facing receiver where collected energy can be extracted via the (shaded) apex of the parabola. We use efficiency-concentration plots to characterize the solar concentrators considered, and to evaluate the potential improvements with secondary concentrators. (author)

  7. Photovoltaic solar concentrator

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2016-03-15

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  8. Concentrated loads on concrete

    DEFF Research Database (Denmark)

    Lorenzen, Karen Grøndahl; Nielsen, Mogens Peter

    1997-01-01

    This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas are devel......This report deals with concentrated loads on concrete.A new upper bound solution in the axisymmetrical case of a point load in the center of the end face of a cylinder is developed.Based on previous work dealing with failure mechanisms and upper bound solutions, new approximate formulas...

  9. RX: a nonimaging concentrator.

    Science.gov (United States)

    Miñano, J C; Benítez, P; González, J C

    1995-05-01

    A detailed description of the design procedure for a new concentrator, RX, and some examples of it's use are given. The method of design is basically the same as that used in the design of two other concentrators: the RR and the XR [Appl. Opt. 31, 3051 (1992)]. The RX is ideal in two-dimensional geometry. The performance of the rotational RX is good when the average angular spread of the input bundle is small: up to 95% of the power of the input bundle can be transferred to the output bundle (with the assumption of a constant radiance for the rays of the input bundle).

  10. A Microfluidic Cell Concentrator

    Science.gov (United States)

    Warrick, Jay; Casavant, Ben; Frisk, Megan; Beebe, David

    2010-01-01

    Cell concentration via centrifugation is a ubiquitous step in many cell culture procedures. At the macroscale, centrifugation suffers from a number of limitations particularly when dealing with small numbers of cells (e.g., less than 50,000). On the other hand, typical microscale methods for cell concentration can affect cell physiology and bias readouts of cell behavior and function. In this paper, we present a microfluidic concentrator device that utilizes the effects of gravity to allow cells to gently settle out of a suspension into a collection region without the use of specific adhesion ligands. Dimensional analysis was performed to compare different device designs and was verified with flow modeling to optimize operational parameters. We are able to concentrate low-density cell suspensions in a microfluidic chamber, achieving a cell loss of only 1.1 ± 0.6% (SD, n=7) with no observed loss during a subsequent cell staining protocol which incorporates ~36 complete device volume replacements. This method provides a much needed interface between rare cell samples and microfluidic culture assays. PMID:20843010

  11. Aluminum concentration in hydrangeas

    International Nuclear Information System (INIS)

    Yanagawa, M.; Haruyama, Y.; Saito, M.

    2008-01-01

    We have been trying to measure concentration of aluminum in Ajisai, Hydrangea macrophylla for these days. But due to bad luck, we have encountered detector trouble for two years in a low. Thus, we have few data to analyze and obtained quite limited results. (author)

  12. Theory of Concentrated Vortices

    DEFF Research Database (Denmark)

    Alekseenko, Sergey; Kuibin, Pavel; Okulov, Valery

    This book presents comprehensive and authoritative coverage of the wide field of concentrated vortices observed in nature and technique. The methods for research of their kinematics and dynamics are considered. Special attention is paid to the flows with helical symmetry. The authors have describ...

  13. A point focusing double parabolic trough concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Murphree, Quincy C. [Kentucky Mountain Bible College, Vancleve, KY (United States)

    2001-07-01

    This article shows that a point focusing solar concentrator can be made from two reflective parabolic troughs, a primary and a secondary, by orienting their longitudinal axes in perpendicular directions and separating them by the difference of their focal lengths along the optical axis. This offers a new alternative to the conventional 3-D paraboloidal concentrator permitting more flexibility in designs for applications requiring high concentrations. Both advantages and disadvantages are discussed. The intensity concentration ratio distribution is calculated in the focal plane and has elliptically shaped contours due to the inherent compensation of errant rays by the concave secondary. The ratio of the major to minor axes was 2.61 for the case considered, resulting in a concentration {approx}2.61 times that of a comparable concentrator without the compensation afforded by a concave secondary. Still, geometrical constraints limit the concentration to about 2000 suns for mirror quality errors of 5 mr. Optimisation of the compensation effect holds potential for improved performance for other concentrator designs. Finally, the functional dependence of the peak concentration and shading factor upon design parameters are presented. (Author)

  14. Concentric Split Flow Filter

    Science.gov (United States)

    Stapleton, Thomas J. (Inventor)

    2015-01-01

    A concentric split flow filter may be configured to remove odor and/or bacteria from pumped air used to collect urine and fecal waste products. For instance, filter may be designed to effectively fill the volume that was previously considered wasted surrounding the transport tube of a waste management system. The concentric split flow filter may be configured to split the air flow, with substantially half of the air flow to be treated traveling through a first bed of filter media and substantially the other half of the air flow to be treated traveling through the second bed of filter media. This split flow design reduces the air velocity by 50%. In this way, the pressure drop of filter may be reduced by as much as a factor of 4 as compare to the conventional design.

  15. Zirconia concentrate chlorination

    International Nuclear Information System (INIS)

    Costa, N.G.; Albuquerque Brocchi, E. de

    1990-01-01

    Chlorination experiments were conducted in order to study the kinetics of gasification of the zirconium oxide present in the zirconia concentrate. The variables studied are temperature (1173 to 1373 K), percentage of reducing agent (12 to 36%) and porosity (22 to 30%). The results indicated a greater influence of temperature and percentage of reducing agent as well as allowed the conclusion that a balance between the levels of these variables is an important factor in the appropriate chlorination conditions. (author)

  16. Thermodynamically efficient solar concentrators

    Science.gov (United States)

    Winston, Roland

    2012-10-01

    Non-imaging Optics is the theory of thermodynamically efficient optics and as such depends more on thermodynamics than on optics. Hence in this paper a condition for the "best" design is proposed based on purely thermodynamic arguments, which we believe has profound consequences for design of thermal and even photovoltaic systems. This new way of looking at the problem of efficient concentration depends on probabilities, the ingredients of entropy and information theory while "optics" in the conventional sense recedes into the background.

  17. Electrolyte Concentrates Treat Dehydration

    Science.gov (United States)

    2009-01-01

    Wellness Brands Inc. of Boulder, Colorado, exclusively licensed a unique electrolyte concentrate formula developed by Ames Research Center to treat and prevent dehydration in astronauts returning to Earth. Marketed as The Right Stuff, the company's NASA-derived formula is an ideal measure for athletes looking to combat dehydration and boost performance. Wellness Brands also plans to expand with products that make use of the formula's effective hydration properties to help treat conditions including heat stroke, altitude sickness, jet lag, and disease.

  18. Chlorination of zirconyte concentrate

    International Nuclear Information System (INIS)

    Costa, N.G.

    1988-01-01

    Chlorination experiments with zirconyte concentrate were carried out in order to study the effects of temperature, percentage of reducing agent and porosity on the gasification of ZrO 2 for 10 and 20 minutes of reaction. Factorial analysis was applied and the results indicated that temperature and percentage of reducing agent were the two only variables effecting the ZrO 2 gasification. (author) [pt

  19. Concentrated Solar Thermoelectric Power

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Gang [MIT; Ren, Zhifeng [University of Houston

    2015-07-09

    The goal of this project is to demonstrate in the lab that solar thermoelectric generators (STEGs) can exceed 10% solar-to-electricity efficiency, and STEGs can be integrated with phase-change materials (PCM) for thermal storage, providing operation beyond daylight hours. This project achieved significant progress in many tasks necessary to achieving the overall project goals. An accurate Themoelectric Generator (TEG) model was developed, which included realistic treatment of contact materials, contact resistances and radiative losses. In terms of fabricating physical TEGs, high performance contact materials for skutterudite TE segments were developed, along with brazing and soldering methods to assemble segmented TEGs. Accurate measurement systems for determining device performance (in addition to just TE material performance) were built for this project and used to characterize our TEGs. From the optical components’ side, a spectrally selective cermet surface was developed with high solar absorptance and low thermal emittance, with thermal stability at high temperature. A measurement technique was also developed to determine absorptance and total hemispherical emittance at high temperature, and was used to characterize the fabricated spectrally selective surfaces. In addition, a novel reflective cavity was designed to reduce radiative absorber losses and achieve high receiver efficiency at low concentration ratios. A prototype cavity demonstrated that large reductions in radiative losses were possible through this technique. For the overall concentrating STEG system, a number of devices were fabricated and tested in a custom built test platform to characterize their efficiency performance. Additionally, testing was performed with integration of PCM thermal storage, and the storage time of the lab scale system was evaluated. Our latest testing results showed a STEG efficiency of 9.6%, indicating promising potential for high performance concentrated STEGs.

  20. Censored correlated cytokine concentrations

    DEFF Research Database (Denmark)

    Andersen, Andreas; Benn, Christine Stabell; Jørgensen, Mathias J

    2013-01-01

    ) can be used to describe the relative concentration between two cytokines, and the GMR ratio (GMRR) can be used to compare two groups. The problem is how to estimate GMRRs from censored distributions.We evaluated methods, including simple deletion and substitution, in simulated and real data. One...... stacking method that uses clustered variance-covariance estimation allowing homogeneous (Stackc) or inhomogeneous (Stackh) variances. We compare it with direct estimation of the bivariate Tobit likelihood function (Bitobit) and multiple imputation. We assess sensitivity to inhomogeneity and non...

  1. Concentrating Solar Power Systems

    Science.gov (United States)

    Pitz-Paal, R.

    2017-07-01

    Development of Concentrating Solar Power Systems has started about 40 years ago. A first commercial implementation was performed between 1985 and 1991 in California. However, a drop in gas prices caused a longer period without further deployment. It was overcome in 2007 when new incentive schemes for renewables in Spain and the US enabled a commercial restart. In 2016, almost 100 commercial CSP plants with more than 5GW are installed worldwide. This paper describes the physical background of CSP technology, its technical characteristics and concepts. Furthermore, it discusses system performances, cost structures and the expected advancement.

  2. Uranium concentration in fossils

    International Nuclear Information System (INIS)

    Okano, J.; Uyeda, C.

    1988-01-01

    Recently it is known that fossil bones tend to accumulate uranium. The uranium concentration, C u in fossils has been measured so far by γ ray spectroscopy or by fission track method. The authors applied secondary ion mass spectrometry, SIMS, to detect the uranium in fossil samples. The purpose of this work is to investigate the possibility of semi-quantitative analyses of uranium in fossils, and to study the correlation between C u and the age of fossil bones. The further purpose of this work is to apply SIMS to measure the distribution of C u in fossil teeth

  3. Theory of Concentrated Vortices

    DEFF Research Database (Denmark)

    Alekseenko, Sergey; Kuibin, Pavel; Okulov, Valery

    This book presents comprehensive and authoritative coverage of the wide field of concentrated vortices observed in nature and technique. The methods for research of their kinematics and dynamics are considered. Special attention is paid to the flows with helical symmetry. The authors have describ...... models of vortex structures used for interpretation of experimental data which serve as a ground for development of theoretical and numerical approaches to vortex investigation. Achievements in the fields of stability analysis, waves on vortices and vortex breakdown are also presented....

  4. Effect of Crude Protein Levels in Concentrate and Concentrate Levels in Diet on Fermentation

    Directory of Open Access Journals (Sweden)

    Dinh Van Dung

    2014-06-01

    Full Text Available The effect of concentrate mixtures with crude protein (CP levels 10%, 13%, 16%, and 19% and diets with roughage to concentrate ratios 80:20, 60:40, 40:60, and 20:80 (w/w were determined on dry matter (DM and organic matter (OM digestibility, and fermentation metabolites using an in vitro fermentation technique. In vitro fermented attributes were measured after 4, 24, and 48 h of incubation respectively. The digestibility of DM and OM, and total volatile fatty acid (VFA increased whereas pH decreased with the increased amount of concentrate in the diet (p<0.001, however CP levels of concentrate did not have any influence on these attributes. Gas production reduced with increased CP levels, while it increased with increasing concentrate levels. Ammonia nitrogen (NH3-N concentration and microbial CP production increased significantly (p<0.05 by increasing CP levels and with increasing concentrate levels in diet as well, however, no significant difference was found between 16% and 19% CP levels. Therefore, 16% CP in concentrate and increasing proportion of concentrate up to 80% in diet all had improved digestibility of DM and organic matter, and higher microbial protein production, with improved fermentation characteristics.

  5. Complex concentrate pretreatment

    International Nuclear Information System (INIS)

    Lokken, R.O.; Scheele, R.D.; Strachan, D.M.; Toste, A.P.

    1991-03-01

    After removal of the transuranics (TRU) by the TRUEX process, complex concentrate waste will be grouted for final storage. The purpose of this project, conducted at the Pacific Northwest Laboratory, is to support a future decision to grout the complexant waste without destruction of the organic contents. It has been demonstrated that grouts with acceptable parameters for the Transportable Grout Facility can be made using actual waste. The acceptability of these grouts from a regulatory view seems to be less of a problem than previously. None of the organics found in the waste have been found on the EPA hazardous chemicals list. Two potential problems with the processing of the complex concentrate wastes were identified during the use of the TRUEX process on samples of several milliliters. One was the amount of foam that is generated during acid addition to the alkaline waste. Some of this foam appears to be of a waxy nature but does redissolve when the waste is strongly acid. The second potential problem is that noticeable amounts of NO x gases are generated. No quantitative measure of the NO x gas generation was made. The problem relates to processing the waste in B-plant where there are no facilities to handle NO x gases. 5 refs., 4 figs., 4 tabs

  6. Dual temperature concentration system

    International Nuclear Information System (INIS)

    Spevack, J.S.

    1975-01-01

    In a dual temperature isotope exchange system--exemplified by exchange of deuterium and protium between water and hydrogen sulfide gas in hot and cold towers, in which the feed stream (water) containing the desired isotope is passed through a pair of towers maintained at different temperatures wherein it effects isotope exchange with countercurrently circulated auxiliary fluid (H 2 S) and is impoverished in said isotope and then disposed of, e.g. discharged to waste,--the flow of isotope enriched auxiliary fluid between said towers (hot H 2 S saturated with water vapor) is divided and a part thereof is adjusted in its temperature (to cold tower conditions) and then passed to the auxiliary fluid impoverishing (cold) tower, while the remainder of the divided flow of such enriched auxiliary fluid is passed through a subsequent isotope concentration treatment to produce a product more highly enriched in the desired isotope and wherein it is also adjusted in its temperature and is impoverished in said isotope during said subsequent treatment before it is delivered to the said auxiliary fluid impoverishing (cold) tower. Certain provisions are made for returning to the hot tower liquid carried as vapor by the remainder of the divided flow to the subsequent isotope concentration treatment, for recovering sensible and latent heat, and for reducing passage of auxiliary fluid to waste

  7. Luminescent solar concentrator

    Directory of Open Access Journals (Sweden)

    Tugce Tosun

    2015-07-01

    Full Text Available Luminescent solar concentrator (LSC is a device that has luminescent molecules embedding or topping polymeric or glass waveguide to generate electricity from sunlight with a photovoltaic cell attachment. LSCs can be employed both in small and large scale projects, independent on the direction or angle of the surface with respect to the sun, promising more freedom for integration in urban environments compared to the traditional PV systems. The aim of the SEB&C PDEng project is to investigate the applicability of this innovative technology in the built environment and to bridge the gap of knowledge linking societal, design and technological aspects. The final goal is to exhibit potential application concepts of LSC developed by co-creative methods at SPARK campus which is a hub for open innovation in built environment. Necessity of a paradigm shift towards sustainable and smart cities came into being due to the significant increase in energy demand of the buildings. The challenge is to increase renewable sources in the energy mix while designing aesthetic environments. Thus, building integrated renewable energy technologies represent a great opportunity to help overcome this current challenge. Smart energy, energy efficiency and use of renewable sources are key aspects to be considered nowadays and many innovative technologies need further exploitation to be commercially viable, such as luminescent solar concentrator.

  8. Pushing concentration of stationary solar concentrators to the limit.

    Science.gov (United States)

    Winston, Roland; Zhang, Weiya

    2010-04-26

    We give the theoretical limit of concentration allowed by nonimaging optics for stationary solar concentrators after reviewing sun- earth geometry in direction cosine space. We then discuss the design principles that we follow to approach the maximum concentration along with examples including a hollow CPC trough, a dielectric CPC trough, and a 3D dielectric stationary solar concentrator which concentrates sun light four times (4x), eight hours per day year around.

  9. Plasma concentrations of misonidazole

    Energy Technology Data Exchange (ETDEWEB)

    Notter, G; Rylander, U; Turesson, I

    1980-10-01

    The plasma concentrations of misonidazole doses between 0.6 and 2.0 g/m/sup 2/ were analyzed in respect to the variation within the same patient and between different patients. Peak plasma levels were observed after 2 hours. The mean plasma levels of misonidazole only at 3 hours were 23.8, 47.0 and 76.5 ..mu..g/ml after misonidazole doses of 0.6, 1.2 g/m/sup 2/, respectively. The half-life of misonidazole only was found to be 8.2 hours for women and 10.5 for men. Good linearity between plasma levels and drug doses was observed after administration of different single doses to the same patient within the dose range 0.6 to 2.0 g/m/sup 2/.

  10. Stress concentration at notches

    CERN Document Server

    Savruk, Mykhaylo P

    2017-01-01

    This book compiles solutions of linear theory of elasticity problems for isotropic and anisotropic bodies with sharp and rounded notches. It contains an overview of established and recent achievements, and presents the authors’ original solutions in the field considered with extensive discussion. The volume demonstrates through numerous, useful examples the effectiveness of singular integral equations for obtaining exact solutions of boundary problems of the theory of elasticity for bodies with cracks and notches. Incorporating analytical and numerical solutions of the problems of stress concentrations in solid bodies with crack-like defects, this volume is ideal for scientists and PhD students dealing with the problems of theory of elasticity and fracture mechanics. Stands as a modern and extensive compendium of solutions to the problems of linear theory of elasticity of isotropic and anisotropic bodies with sharp and rounded notches; Adopts a highly reader-friendly layout of tables, charts, approximation ...

  11. Concentration solar thermal power

    International Nuclear Information System (INIS)

    Livet, F.

    2011-01-01

    As the production of electricity by concentration solar power (CSP) installations is said to be a source of energy for the future, the author discusses past experiments (notably the French Thermis project), and the different techniques which are currently being used. He indicates the regions which appear to be the most appropriate for this technique. He presents the three main techniques: parabolic cylinder, tower, and Stirling cycle installations. He discusses the issue of intermittency. He proposes an assessment of prices and of their evolution, and indicates the investments made in different installations (in Italy, Spain, Germany and Portugal). He comments the case of hybrid installations (sun and gas), evokes the Desertec project proposed by the German industry which comprises a set of hybrid installations. He notices that there is no significant technological evolution for this process

  12. Concentrating solar thermal power.

    Science.gov (United States)

    Müller-Steinhagen, Hans

    2013-08-13

    In addition to wind and photovoltaic power, concentrating solar thermal power (CSP) will make a major contribution to electricity provision from renewable energies. Drawing on almost 30 years of operational experience in the multi-megawatt range, CSP is now a proven technology with a reliable cost and performance record. In conjunction with thermal energy storage, electricity can be provided according to demand. To date, solar thermal power plants with a total capacity of 1.3 GW are in operation worldwide, with an additional 2.3 GW under construction and 31.7 GW in advanced planning stage. Depending on the concentration factors, temperatures up to 1000°C can be reached to produce saturated or superheated steam for steam turbine cycles or compressed hot gas for gas turbine cycles. The heat rejected from these thermodynamic cycles can be used for sea water desalination, process heat and centralized provision of chilled water. While electricity generation from CSP plants is still more expensive than from wind turbines or photovoltaic panels, its independence from fluctuations and daily variation of wind speed and solar radiation provides it with a higher value. To become competitive with mid-load electricity from conventional power plants within the next 10-15 years, mass production of components, increased plant size and planning/operating experience will be accompanied by technological innovations. On 30 October 2009, a number of major industrial companies joined forces to establish the so-called DESERTEC Industry Initiative, which aims at providing by 2050 15 per cent of European electricity from renewable energy sources in North Africa, while at the same time securing energy, water, income and employment for this region. Solar thermal power plants are in the heart of this concept.

  13. Radiometers for radon concentration in air

    International Nuclear Information System (INIS)

    Bartak, J.; Machaj, B.; Pienkos, J.P.

    2002-01-01

    Constant grow of science and technology stimulates development of new improved measuring tools. New measuring demand arise also in radon concentration measurements. Varying rock stress and rock cracks influencing radon emanation encouraged research aimed at use of this phenomenon to predict crumps of mine formation among others based on variation of radon emanation. A measuring set was developed in the Institute of Nuclear Chemistry and Technology enabling long term monitoring of radon concentration in mine bore-hole. The set consists probe and probe controller. Detection threshold of the probe is 230 Bq/m 3 . The set can operate in the environment with methane explosion hazard. A radiometer employing Lucas cell as radiation detector for radon concentration in air was also developed its detection threshold is approx. 10 Bq/m 3 . Replaceable Lucas cell of the radiometer allows for measurement of high as well as low radon concentration in short time interval. (author)

  14. Preparation of selective molybdenum concentrate from collective coppermolybdenum concentrate

    Directory of Open Access Journals (Sweden)

    N. Tusupbaev

    2016-06-01

    Full Text Available The paper considers possibilities of selective separation of the concentrate of copper and molybdenum from a collective copper-molybdenum concentrate of Aktogay deposit using regrinding and conventional flotation reagents. In the case of conventional flotoreagents, the content of molybdenum in a molybdenum concentrate was 8.0% at extraction effectiveness 83.12%. At 27.96% extraction degree of copper, it’s content in the concentrate equaled to 21.3%. After regrinding, molybdenum content in the concentrate was 24.0% at the extraction effectiveness 59.63%, and copper content in the concentrate was 21.9% at the recovery of 61.23%. Thus, the regrinding of a collective copper-molybdenum concentrate resulted in an increase in the content of molybdenum in molybdenum concentrate by 16%, and the copper concentration increased by 0.6%.

  15. Workplace Concentration of Immigrants

    Science.gov (United States)

    Andersson, Fredrik; García-Pérez, Mónica; Haltiwanger, John; McCue, Kristin; Sanders, Seth

    2014-01-01

    Casual observation suggests that in most U.S. urban labor markets, immigrants have more immigrant coworkers than native-born workers do. While seeming obvious, this excess tendency to work together has not been precisely measured, nor have its sources been quantified. Using matched employer–employee data from the U.S. Census Bureau Longitudinal Employer-Household Dynamics (LEHD) database on a set of metropolitan statistical areas (MSAs) with substantial immigrant populations, we find that, on average, 37% of an immigrant’s coworkers are themselves immigrants; in contrast, only 14% of a native-born worker’s coworkers are immigrants. We decompose this difference into the probability of working with compatriots versus with immigrants from other source countries. Using human capital, employer, and location characteristics, we narrow the mechanisms that might explain immigrant concentration. We find that industry, language, and residential segregation collectively explain almost all the excess tendency to work with immigrants from other source countries, but they have limited power to explain work with compatriots. This large unexplained compatriot component suggests an important role for unmeasured country-specific factors, such as social networks. PMID:25425452

  16. Conical electromagnetic radiation flux concentrator

    Science.gov (United States)

    Miller, E. R.

    1972-01-01

    Concentrator provides method of concentrating a beam of electromagnetic radiation into a smaller beam, presenting a higher flux density. Smaller beam may be made larger by sending radiation through the device in the reverse direction.

  17. Membrane distillation for milk concentration

    NARCIS (Netherlands)

    Moejes, S.N.; Romero Guzman, Maria; Hanemaaijer, J.H.; Barrera, K.H.; Feenstra, L.; Boxtel, van A.J.B.

    2015-01-01

    Membrane distillation is an emerging technology to concentrate liquid products while producing high quality water as permeate. Application for desalination has been studied extensively the past years, but membrane distillation has also potential to produce concentrated food products like

  18. Calcium concentration in the CAPD dialysate

    DEFF Research Database (Denmark)

    Bro, S; Brandi, L; Daugaard, H

    1998-01-01

    OBJECTIVE: To evaluate risk/benefit of various continuous ambulatory peritoneal dialysis (CAPD) dialysate calcium concentrations. DATA SOURCES: A review of the literature on the effects of various CAPD dialysate Ca concentrations on plasma Ca, plasma phosphate, plasma parathyroid hormone (PTH......), doses of calcium carbonate, doses of vitamin D analogs, and requirements of aluminum-containing phosphate binders. STUDY SELECTION: Eleven studies of nonselected CAPD patients, and 13 studies of CAPD patients with hypercalcemia were reviewed. RESULTS: In nonselected CAPD patients, treatment...... with a reduced dialysate Ca concentration (1.00, 1.25, or 1.35 mmol/L) improved the tolerance to calcium carbonate and/or vitamin D metabolites and reduced the need for Al-containing phosphate binders. When using dialysate Ca 1.25 or 1.35 mmol/L, the initial decrease of plasma Ca and increase of PTH could easily...

  19. Wafer integrated micro-scale concentrating photovoltaics

    Science.gov (United States)

    Gu, Tian; Li, Duanhui; Li, Lan; Jared, Bradley; Keeler, Gordon; Miller, Bill; Sweatt, William; Paap, Scott; Saavedra, Michael; Das, Ujjwal; Hegedus, Steve; Tauke-Pedretti, Anna; Hu, Juejun

    2017-09-01

    Recent development of a novel micro-scale PV/CPV technology is presented. The Wafer Integrated Micro-scale PV approach (WPV) seamlessly integrates multijunction micro-cells with a multi-functional silicon platform that provides optical micro-concentration, hybrid photovoltaic, and mechanical micro-assembly. The wafer-embedded micro-concentrating elements is shown to considerably improve the concentration-acceptance-angle product, potentially leading to dramatically reduced module materials and fabrication costs, sufficient angular tolerance for low-cost trackers, and an ultra-compact optical architecture, which makes the WPV module compatible with commercial flat panel infrastructures. The PV/CPV hybrid architecture further allows the collection of both direct and diffuse sunlight, thus extending the geographic and market domains for cost-effective PV system deployment. The WPV approach can potentially benefits from both the high performance of multijunction cells and the low cost of flat plate Si PV systems.

  20. Concentrating on caustic

    International Nuclear Information System (INIS)

    Collins, Richard

    2010-01-01

    Full text: First there was the Beer Battery, which aimed to generate electricity from brewery wastewater using a microbial fuel cell (MFC). Trials at Foster's Yatala brewery in Queensland in 2007 ran into challenges around the cost of electricity and duration of treatment, but they also revealed a new possibility. Komeel Rabaey, a University of Queensland specialist in microbial dynamics with a particular passion for bioelectrochemical systems, recognised the potential to extract sodium hydroxide - caustic soda - out of wastewater in a form suitable for reuse. In 2008 he converted such a system into a lab-scale caustic recovery plant, then upsized it to a one litre test reactor, which is again running at the Yatala brewery. The concept flips wastewater treatment on its head, seeing the discharge as a resource to be harvested rather than a cost and a contaminant load to be managed. “We typically aim to make a concentration of about four per cent caustic. That is what is easily achievable with the system and you will also note a lot of industries use caustic at four per cent,” said Dr Rabaey. “So you can use the wastewater from the plant to drive caustic production, with the extra advantage of removing enormous amounts of sodium.” Sodium hydroxide is a ubiquitous industrial compound used in pH regulation, as a cleaning agent in clean-in-place systems and variously in pulp and paper, textiles and food processing. Dr Rabaey wants to close the loop on caustic. Industries along the Murray-Darling basin, for example, truck in a lot of it from outside the area and then discharge it with their wastewater into the salt-sensitive river system. “If you use a bioelectrochemical system to recover the sodium hydroxide, you are not even importing the sodium into the area but recycling the sodium the whole time on-site,” he told WME. Get the technology right and he reckons a three-year payback on investment is readily achievable. A microbial fuel cell oxidises organics

  1. NCCDS configuration management process improvement

    Science.gov (United States)

    Shay, Kathy

    1993-01-01

    By concentrating on defining and improving specific Configuration Management (CM) functions, processes, procedures, personnel selection/development, and tools, internal and external customers received improved CM services. Job performance within the section increased in both satisfaction and output. Participation in achieving major improvements has led to the delivery of consistent quality CM products as well as significant decreases in every measured CM metrics category.

  2. Apparatus for concentrating by dual temperature exchange

    International Nuclear Information System (INIS)

    Spevack, J.S.

    1975-01-01

    Improvements in an apparatus for isotope concentration by dual temperature exchange between feed and auxiliary fluids in a multistage system are described. The first fluid is a vaporizable liquid and the auxiliary fluid a gas, the apparatus having means for cascading the auxiliary fluid and the feed fluid in vapor and preferably also in liquid form. The apparatus also contains new combinations of means for improving the heating and/or cooling and/or humidifying and/or dehumidifying operations of the system. The reactants in the example given are hydrogen sulfide gas and liquid water

  3. Effects on the improvement and retention strength of two training programs with regular and concentrated loads in subjects untrained Efectos sobre la mejora y retención de la fuerza de dos programas de entrenamiento con cargas regulares y concentradas en sujetos

    Directory of Open Access Journals (Sweden)

    F. Navarro

    2010-09-01

    Full Text Available

    In this study it is compared the improvement and retention of the maximum dynamic strength in 35 subjects untrained, after the application of two training programs of equal content and different loads distribution (with/without concentration of loads = SC/CC so that in one of the programs the double of total volume takes place. Measurements from high maximum weight in 1RM, maximum strength, and total average strength were taken, with the system of measurement of dynamic forces ISOCONTROL 3.6., in the exercise of squat (SQ, before (PRE -, and at the end of the treatment (POST 1, as well as after 1 (POST 2 and 2 months (POST 3 of its conclusion. Both groups improved the maximum dynamic strength of highly significant form (p<0.01 during the cycle of training (29% SC - 36% CC, not existing significant differences between groups in any of the measured variables. In conclusion, after 8 weeks of strength training, the maximum dynamic strength of significant form highly in subjects untrained can be improved, and similars gains are obtained, as much with a distribution of concentrated loads, like with a distribution without concentration of loads where half of volume has been made that in the previous one.432
    KEY WORDS: Training, strength, distribution of loads, volume.

     

    En este estudio se compara la mejora y retención de la fuerza dinámica máxima en 35 sujetos no entrenados, tras la aplicación de dos programas de entrenamiento de igual contenido y diferente distribución de la carga (sin/con concentración de cargas =SC/CC de forma que en uno de los programas se efectúa el doble de volumen total. Se tomaron mediciones de peso máximo elevado en 1RM, fuerza máxima, y fuerza media total, con el sistema de medición de fuerzas dinámicas ISOCONTROL 3.6., en el ejercicio de squat (SQ, antes (PRE-, y al final del tratamiento (POST

  4. White butterflies as solar photovoltaic concentrators

    Science.gov (United States)

    Shanks, Katie; Senthilarasu, S.; Ffrench-Constant, Richard H.; Mallick, Tapas K.

    2015-07-01

    Man’s harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies’ wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies’ thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

  5. White butterflies as solar photovoltaic concentrators.

    Science.gov (United States)

    Shanks, Katie; Senthilarasu, S; Ffrench-Constant, Richard H; Mallick, Tapas K

    2015-07-31

    Man's harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies' wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies' thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

  6. [Ozone concentration distribution of urban].

    Science.gov (United States)

    Yin, Yong-quan; Li, Chang-mei; Ma, Gui-xia; Cui, Zhao-jie

    2004-11-01

    The increase of ozone concentration in urban is one of the most important research topics on environmental science. With the increase of nitrogen oxides and hydrogen-carbon compounds which are exhausted from cars, the ozone concentration in urban is obviously increased on sunlight, and threat of photochemistry smog will be possible. Therefore, it is very important to monitor and study the ozone concentration distribution in urban. The frequency-distribution, diurnal variation and monthly variation of ozone concentration were studied on the campus of Shandong University during six months monitoring. The influence of solar radiation and weather conditions on ozone concentration were discussed. The frequency of ozone concentration less than 200 microg/m3 is 96.88%. The ozone concentration has an obvious diurnal variation. The ozone concentration in the afternoon is higher than in the morning and in the evening. The maximum appears in June, when it is the strong solar radiation and high air-temperature. The weather conditions also influence the ozone concentration. The ozone concentration in clear day is higher than in rainy and cloudy day.

  7. Low concentrator PV optics optimization

    Science.gov (United States)

    Sharp, Leonard; Chang, Ben

    2008-08-01

    Purpose: Cost reduction is a major focus of the solar industry. Thin film technologies and concentration systems are viable ways to reducing cost, with unique strengths and weakness for both. Most of the concentrating PV work focuses on high concentration systems for reducing energy cost. Meanwhile, many believe that low concentrators provide significant cost reduction potential while addressing the mainstream PV market with a product that acts as a flat panel replacement. This paper analyzes the relative benefit of asymmetric vs. symmetric optics for low-concentrators in light of specific PV applications. Approach: Symmetric and asymmetric concentrating PV module performance is evaluated using computer simulation to determine potential value across various geographic locations and applications. The selected optic design is modeled against standard cSi flat panels and thin film to determine application fit, system level energy density and economic value. Results: While symmetric designs may seem ideal, asymmetric designs have an advantage in energy density. Both designs are assessed for aperture, optimum concentration ratio, and ideal system array configuration. Analysis of performance across climate specific effects (diffuse, direct and circumsolar) and location specific effects (sunpath) are also presented. The energy density and energy production of low concentrators provide a compelling value proposition. More significantly, the choice of optics for a low concentrating design can affect real world performance. With the goal of maximizing energy density and return on investment, this paper presents the advantages of asymmetric optic concentration and illustrates the value of this design within specific PV applications.

  8. Hybrid Perovskites: Prospects for Concentrator Solar Cells.

    Science.gov (United States)

    Lin, Qianqian; Wang, Zhiping; Snaith, Henry J; Johnston, Michael B; Herz, Laura M

    2018-04-01

    Perovskite solar cells have shown a meteoric rise of power conversion efficiency and a steady pace of improvements in their stability of operation. Such rapid progress has triggered research into approaches that can boost efficiencies beyond the Shockley-Queisser limit stipulated for a single-junction cell under normal solar illumination conditions. The tandem solar cell architecture is one concept here that has recently been successfully implemented. However, the approach of solar concentration has not been sufficiently explored so far for perovskite photovoltaics, despite its frequent use in the area of inorganic semiconductor solar cells. Here, the prospects of hybrid perovskites are assessed for use in concentrator solar cells. Solar cell performance parameters are theoretically predicted as a function of solar concentration levels, based on representative assumptions of charge-carrier recombination and extraction rates in the device. It is demonstrated that perovskite solar cells can fundamentally exhibit appreciably higher energy-conversion efficiencies under solar concentration, where they are able to exceed the Shockley-Queisser limit and exhibit strongly elevated open-circuit voltages. It is therefore concluded that sufficient material and device stability under increased illumination levels will be the only significant challenge to perovskite concentrator solar cell applications.

  9. Nonimaging optics in luminescent solar concentration.

    Science.gov (United States)

    Markman, B D; Ranade, R R; Giebink, N C

    2012-09-10

    Light trapped within luminescent solar concentrators (LSCs) is naturally limited in angular extent by the total internal reflection critical angle, θcrit, and hence the principles of nonimaging optics can be leveraged to increase LSC concentration ratio by appropriately reshaping the edges. Here, we use rigorous ray-tracing simulations to explore the potential of this concept for realistic LSCs with compound parabolic concentrator (CPC)-tapered edges and show that, when applied to a single edge, the concentration ratio is increased by 23% while maintaining >90% of the original LSC optical efficiency. Importantly, we find that CPC-tapering all of the edges enables a significantly greater intensity enhancement up to 35% at >90% of the original optical efficiency, effectively enabling two-dimensional concentration through a cooperative, ray-recycling effect in which rays rejected by one CPC are accepted by another. These results open up a significant opportunity to improve LSC performance at virtually no added manufacturing cost by incorporating nonimaging optics into their design.

  10. Optical assessment of nonimaging concentrators.

    Science.gov (United States)

    Timinger, A; Kribus, A; Ries, H; Smith, T; Walther, M

    2000-11-01

    An optical measurement method for nonimaging radiation concentrators is proposed. A Lambertian light source is placed in the exit aperture of the concentrator. Looking into the concentrator's entrance aperture from a remote position, one can photograph the transmission patterns. The patterns show the transmission of radiation through the concentrator with the full resolution of the four-dimensional phase space of geometric optics. By matching ray-tracing simulations to the measurement, one can achieve detailed and accurate information about the geometry of the concentrator. This is a remote, noncontact measurement and can be performed in situ for installed concentrators. Additional information regarding small-scale reflector waviness and surface reflectivity can also be obtained from the same measurement with additional analysis.

  11. A compact spectrum splitting concentrator for high concentration photovoltaics based on the dispersion of a lens

    Science.gov (United States)

    He, J.; Flowers, C. A.; Yao, Y.; Atwater, H. A.; Rockett, A. A.; Nuzzo, R. G.

    2018-06-01

    Photovoltaic devices used in conjunction with functional optical elements for light concentration and spectrum splitting are known to be a viable approach for highly efficient photovoltaics. Conventional designs employ discrete optical elements, each with the task of either performing optical concentration or separating the solar spectrum. In the present work, we examine the performance of a compact photovoltaic architecture in which a single lens plays a dual role as both a concentrator and a spectrum splitter, the latter made possible by exploiting its intrinsic dispersion. A four-terminal two-junction InGaP/GaAs device is prepared to validate the concept and illustrates pathways for improvements. A spectral separation in the visible range is demonstrated at the focal point of a plano-convex lens with a geometric concentration ratio of 1104X with respect to the InGaP subcell.

  12. Maximum Permissible Concentrations and Negligible Concentrations for pesticides

    NARCIS (Netherlands)

    Crommentuijn T; Kalf DF; Polder MD; Posthumus R; Plassche EJ van de; CSR

    1997-01-01

    Maximum Permissible Concentrations (MPCs) and Negligible Concentrations (NCs) derived for a series of pesticides are presented in this report. These MPCs and NCs are used by the Ministry of Housing, Spatial Planning and the Environment (VROM) to set Environmental Quality Objectives. For some of the

  13. Ideal 3D asymmetric concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Botella, Angel [Departamento Fisica Aplicada a los Recursos Naturales, Universidad Politecnica de Madrid, E.T.S.I. de Montes, Ciudad Universitaria s/n, 28040 Madrid (Spain); Fernandez-Balbuena, Antonio Alvarez; Vazquez, Daniel; Bernabeu, Eusebio [Departamento de Optica, Universidad Complutense de Madrid, Fac. CC. Fisicas, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2009-01-15

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used for producing reflective and refractive optical devices, including reverse engineering techniques. In this paper we apply photometric field theory and elliptic ray bundles method to study 3D asymmetric - without rotational or translational symmetry - concentrators, which can be useful components for nontracking solar applications. We study the one-sheet hyperbolic concentrator and we demonstrate its behaviour as ideal 3D asymmetric concentrator. (author)

  14. Antibiotic concentrations in intestinal mucosa.

    Science.gov (United States)

    Malmborg, A S

    1985-01-01

    The concentrations in the intestinal mucosa after the initial dose of cefoxitin, piperacillin and clindamycin have been studied. The antibiotics were given at the induction of anesthesia as prophylaxis to patients undergoing elective colorectal surgery. The concentrations of the antibiotics in serum and intestinal mucosa taken during the operation were determined by the microbiological agar diffusion method. Therapeutic concentrations in intestinal mucosa were maintained during the major part of the operation period. The mean mucosa/serum concentration ratios were for cefoxitin 0.4, for piperacillin 0.5 and for clindamycin 1.2.

  15. The effects of trioctyl trimellitate concentration on crosslinking

    International Nuclear Information System (INIS)

    Jamaliah Sharif; Rozana Abu Bakar

    1997-01-01

    The effects of trimellitate type plasticizer concentration on PVC formulation were investigated. The results show that the degree of crosslinking is higher in the PVC compounds containing lower concentration of plasticizer compared to others. The tensile properties were decreased with the increase of plasticizer. However, the ageing properties of the lower concentration samples were very poor. The electrical properties of the compounds were acceptable with the volume resistivity value above 1014 . The heat deformation properties of the samples also improved after irradiation

  16. Alcoholic fermentation by immobilized yeast at high sugar concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Holcberg, I.B.; Margalith, P.

    1981-01-01

    Glucose fermentation by Saccharomyces cerevisiae immobilized by entrapment in agar, carrageenan, alginate and polyacrylamide gels, was compared to that of freely suspended cells at concentration of 10-50% (w.w.) sugar. The rate of ethanol production by the entrapped cells was 20-25% higher than that of the free cells. Concentrations of up to 14.5% w/w ethanol (30% glucose initial concentration) could be obtained. A number of hypotheses for the improved alcoholic fermentation are discussed.

  17. School concentration and school travel

    NARCIS (Netherlands)

    De Boer, E.

    2010-01-01

    The purpose of the research as described in this Doctor’s thesis is twofold. Firstly it is to define in how far Dutch facilities for primary and secondary education were subjected to spatial concentration during recent decades. Secondly it is intended to assess what this concentration implied for

  18. Optimal concentrations in transport systems

    Science.gov (United States)

    Jensen, Kaare H.; Kim, Wonjung; Holbrook, N. Michele; Bush, John W. M.

    2013-01-01

    Many biological and man-made systems rely on transport systems for the distribution of material, for example matter and energy. Material transfer in these systems is determined by the flow rate and the concentration of material. While the most concentrated solutions offer the greatest potential in terms of material transfer, impedance typically increases with concentration, thus making them the most difficult to transport. We develop a general framework for describing systems for which impedance increases with concentration, and consider material flow in four different natural systems: blood flow in vertebrates, sugar transport in vascular plants and two modes of nectar drinking in birds and insects. The model provides a simple method for determining the optimum concentration copt in these systems. The model further suggests that the impedance at the optimum concentration μopt may be expressed in terms of the impedance of the pure (c = 0) carrier medium μ0 as μopt∼2αμ0, where the power α is prescribed by the specific flow constraints, for example constant pressure for blood flow (α = 1) or constant work rate for certain nectar-drinking insects (α = 6). Comparing the model predictions with experimental data from more than 100 animal and plant species, we find that the simple model rationalizes the observed concentrations and impedances. The model provides a universal framework for studying flows impeded by concentration, and yields insight into optimization in engineered systems, such as traffic flow. PMID:23594815

  19. Micro-evaporation electrolyte concentrator

    NARCIS (Netherlands)

    Timmer, B.H.; van Delft, K.M.; Olthuis, Wouter; Bergveld, Piet; van den Berg, Albert

    2003-01-01

    The sensitivity of miniaturized chemical analysis systems depends most of the time on the obtainable detection limit. Concentrating the analyte prior to the detection system can enhance the detection limit. In this writing an analyte concentrator is presented that makes use of evaporation to

  20. Radon concentration in The Netherlands

    International Nuclear Information System (INIS)

    Meijer, R.J. de; Put, L.W.; Veldhuizen, A.

    1986-02-01

    In 1000 dwellings, which can be assumed to be an reasonable representation of the average Dutch dwellings, time averaged radon concentrations, radon daughter concentrations and gamma-exposure tempi are determined during a year with passive dosemeters. They are also determined outdoor at circa 200 measure points. (Auth.)

  1. Ion climate and radon concentration

    International Nuclear Information System (INIS)

    Busbarna, L.

    1981-01-01

    Characteristic values of radon concentration in natural ion climate and in open air were compared and the effect of artificially produced negative ion excess on the radon concentration of air was studied. The results show that the radon concentration measurable at the rise of negative ion excess is smaller than that in the case of natural equilibrium. This effect can be utilized lowering the background of the scintillation chambers, thus increasing their sensitivity. The negative ions of the artificial ion climate lower radon concentration in closed space. The question arises whether only the ion climate is responsible for the effects on the organism and on the nervous system or the radon concentration of the air also contributes to them. (author)

  2. Ideal flux field dielectric concentrators.

    Science.gov (United States)

    García-Botella, Angel

    2011-10-01

    The concept of the vector flux field was first introduced as a photometrical theory and later developed in the field of nonimaging optics; it has provided new perspectives in the design of concentrators, overcoming standard ray tracing techniques. The flux field method has shown that reflective concentrators with the geometry of the field lines achieve the theoretical limit of concentration. In this paper we study the role of surfaces orthogonal to the field vector J. For rotationally symmetric systems J is orthogonal to its curl, and then a family of surfaces orthogonal to the lines of J exists, which can be called the family of surfaces of constant pseudopotential. Using the concept of the flux tube, it is possible to demonstrate that refractive concentrators with the shape of these pseudopotential surfaces achieve the theoretical limit of concentration.

  3. Calculation of radon concentration in water by toluene extraction method

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Masaaki [Tokyo Metropolitan Isotope Research Center (Japan)

    1997-02-01

    Noguchi method and Horiuchi method have been used as the calculation method of radon concentration in water. Both methods have two problems in the original, that is, the concentration calculated is changed by the extraction temperature depend on the incorrect solubility data and the concentration calculated are smaller than the correct values, because the radon calculation equation does not true to the gas-liquid equilibrium theory. However, the two problems are solved by improving the radon equation. I presented the Noguchi-Saito equation and the constant B of Horiuchi-Saito equation. The calculating results by the improved method showed about 10% of error. (S.Y.)

  4. AUDIT MARKET CONCENTRATION – EVIDENCE FROM CROATIA

    Directory of Open Access Journals (Sweden)

    Sanja Sever Mališ

    2015-12-01

    Full Text Available Statutory audit is designated to protect the public interest and has a significant impact on the overall economy. There are concerns that the Big Four audit firms have become too dominant and that the collapse of one of these firms would disrupt the whole financial system. In terms of revenues received, the total market share of the Big Four audit firms for listed companies exceeds 90% in a vast majority of European Union Member States. Prior studies have shown that high audit market concentration limits the choice of auditor for large companies and sets a high barrier of entry for mid-tier audit firms, while the effect on audit quality and audit fees is still unclear. Therefore, the regulators are considering reforms to dilute the Big Four’s dominance and improve competition in the audit market. The paper reviews the proposed and implemented measures that are the most common, together with their advantages and drawbacks. In addition, the characteristics of the audit market in Croatia are investigated, with a focus on market concentration measured by standard measures such as the Concentration rate, the Herfindahl Hirschman Index and the Gini coefficient. According to market shares based on total clients’ assets and revenues, the audit market for listed companies is moderately to highly concentrated, with a decrease in the five-year period (2013 compared to 2008.

  5. Efecto sobre la mejora y retención de la fuerza de un programa de entrenamiento de fuerza con cargas concentradas en sujetos no entrenados. Effect on the strength improvement and retention during a training program with concentrated loads in non trained subjects.

    Directory of Open Access Journals (Sweden)

    Navarro Valdivielso, Fernando

    2007-04-01

    Full Text Available ResumenEn este estudio se ha analizado la mejora y retención de la fuerza en 34 sujetos no entrenados, distribuidos de forma aleatoria en un grupo experimental (GE (n=17 que efectuó un programa de entrenamiento para la mejora de la misma de 9 semanas de duración, realizando 4 sesiones consecutivas de entrenamiento semanal, y un grupo control (GC (n=17 que no llevó a cabo ningún entrenamiento. Se tomaron mediciones del peso máximo elevado en 1RM, la fuerza máxima, y la fuerza media total, con el sistema de medición de fuerzas dinámicas Isocontrol 3.6, en el ejercicio de squat (SQ, antes (PRE-, en la mitad (MED- y al final del tratamiento (POST 1, así como tras 1 (POST 2 y 2 meses (POST 3 de la finalización mismo. En el GE, las ganancias de fuerza fueron altamente significativas (pAbstractIn this study has analyzed the improvement and retention of strength in 34 nontrained subjects, randomized in an experimental group(GE (n=17 who realized a strength training program during 9 weeks, making 4 consecutive sessions of weekly training, and a control group (GC (n=17 who did not realized any training. The 1 repetition maximum (1RM, maximum strength, total mean strength, were measured with ISOCONTROL 3.6. device in squat (SQ. The measured were done before (PRE-, in the middle (MED-, at the end of the treatment (POST 1, as well as after 1 and 2 months of the conclusion of the same one. In the experimental group, the strength gains were highly significant as much in the middle (19%, as at the end of the training program (35%, and even after 2 months of the conclusion of the same one (40%. In the GC significant changes did not take place. In conclusion, after 9 weeks of strength training, can be obtained improvements of same highly significant using concentrated loads in nontrained subjects, and they are possible to be continued reaching greater gains during at least other 8 weeks after more finalized the training.

  6. Tank waste concentration mechanism study

    International Nuclear Information System (INIS)

    Pan, L.C.; Johnson, L.J.

    1994-09-01

    This study determines whether the existing 242-A Evaporator should continue to be used to concentrate the Hanford Site radioactive liquid tank wastes or be replaced by an alternative waste concentration process. Using the same philosophy, the study also determines what the waste concentration mechanism should be for the future TWRS program. Excess water from liquid DST waste should be removed to reduce the volume of waste feed for pretreatment, immobilization, and to free up storage capacity in existing tanks to support interim stabilization of SSTS, terminal cleanout of excess facilities, and other site remediation activities

  7. Advanced reflector materials for solar concentrators

    Science.gov (United States)

    Jorgensen, Gary; Williams, Tom; Wendelin, Tim

    1994-10-01

    This paper describes the research and development at the US National Renewable Energy Laboratory (NREL) in advanced reflector materials for solar concentrators. NREL's research thrust is to develop solar reflector materials that maintain high specular reflectance for extended lifetimes under outdoor service conditions and whose cost is significantly lower than existing products. Much of this work has been in collaboration with private-sector companies that have extensive expertise in vacuum-coating and polymer-film technologies. Significant progress and other promising developments will be discussed. These are expected to lead to additional improvements needed to commercialize solar thermal concentration systems and make them economically attractive to the solar manufacturing industry. To explicitly demonstrate the optical durability of candidate reflector materials in real-world service conditions, a network of instrumented outdoor exposure sites has been activated.

  8. Recent developments in luminescent solar concentrators

    Science.gov (United States)

    van Sark, W. G. J. H. M.

    2014-10-01

    High efficiency photovoltaic devices combine full solar spectrum absorption and effective generation and collection of charge carriers, while commercial success depends on cost effectiveness in manufacturing. Spectrum modification using down shifting has been demonstrated in luminescent solar concentrators (LSCs) since the 1970s, as a cheap alternative for standard c-Si technology. LSCs consist of a highly transparent plastic plate, in which luminescent species are dispersed, which absorb incident light and emit light at a red-shifted wavelength, with high quantum efficiency. Material issues have hampered efficiency improvements, in particular re-absorption of light emitted by luminescent species and stability of these species. In this contribution, approaches are reviewed on minimizing re-absorption, which should allow surpassing the 10% luminescent solar concentrator efficiency barrier.

  9. GRIN planar waveguide concentrator used with a single axis tracker.

    Science.gov (United States)

    Bouchard, Sébastien; Thibault, Simon

    2014-03-10

    It is generally accepted that small to medium level concentrators could be used as cost-competitive replacements for tracked solar panels. The objective is to design a system that can reach a good level of sun concentration with only one sun-tracking axis and is cheap to fabricate. As the most critical parameter for all concentrator designs, optical efficiency needed improvement to reduce the cost of power produced by our system. By using a graded-index planar waveguide with an index profile similar to SELFOC fiber, the ray's path can be controlled. Also, the concentrator can be fabricated in a single block, which reduces Fresnel reflections. Overall, the optical efficiency can be improved by as much as 33% compared to the same system made with a homogeneous waveguide. Furthermore, the ability to cost-effectively fabricate the concentrator by molding can be preserved, making it possible to reduce the cost of the solar power produced.

  10. Fibrinogen concentrate in bleeding patients

    DEFF Research Database (Denmark)

    Wikkelsø, Anne; Lunde, Jens; Johansen, Mathias

    2013-01-01

    Hypofibrinogenaemia is associated with increased morbidity and mortality, but the optimal treatment level, the use of preemptive treatment and the preferred source of fibrinogen remain disputed. Fibrinogen concentrate is increasingly used and recommended for bleeding with acquired haemostatic...

  11. Thermodynamic efficiency of solar concentrators.

    Science.gov (United States)

    Shatz, Narkis; Bortz, John; Winston, Roland

    2010-04-26

    The optical thermodynamic efficiency is a comprehensive metric that takes into account all loss mechanisms associated with transferring flux from the source to the target phase space, which may include losses due to inadequate design, non-ideal materials, fabrication errors, and less than maximal concentration. We discuss consequences of Fermat's principle of geometrical optics and review étendue dilution and optical loss mechanisms associated with nonimaging concentrators. We develop an expression for the optical thermodynamic efficiency which combines the first and second laws of thermodynamics. As such, this metric is a gold standard for evaluating the performance of nonimaging concentrators. We provide examples illustrating the use of this new metric for concentrating photovoltaic systems for solar power applications, and in particular show how skewness mismatch limits the attainable optical thermodynamic efficiency.

  12. Ultra Low Concentration Adsorption Equilibria

    National Research Council Canada - National Science Library

    Mahle, John J; Buettner, Leonard C; LeVan, M. D; Schindler, Bryan J

    2006-01-01

    .... Specifically this work focuses on novel experimental and modeling methods to characterize and predict at ultra-low chemical vapor concentrations the protection afforded by adsorption-based vapor filtration systems...

  13. Adiabatic theorem and spectral concentration

    International Nuclear Information System (INIS)

    Nenciu, G.

    1981-01-01

    The spectral concentration of arbitrary order, for the Stark effect is proved to exist for a large class of Hamiltonians appearing in nonrelativistic and relativistic quantum mechanics. The results are consequences of an abstract theorem about the spectral concentration for self-ad oint operators. A general form of the adiabatic theorem of quantum mechanics, generalizing an earlier result of the author as well as some results of Lenard, is also proved [ru

  14. Collaborative Improvement

    DEFF Research Database (Denmark)

    Kaltoft, Rasmus

    The thesis data have been collected in the EU-sponsored project: Collaborative Improvement Tool for the Extended Manufacturing Enterprise, CO-IMPROVE. In this project four universities (Denmark, Ireland, Italy, and The Netherlands), two software vendors (Greece and Sweden) and three companies...... (Denmark, Italy and The Netherlands) each with three to five suppliers were involved. The CO-IMPROVE project and the thesis is based on “action research” and “action learning”. The main aim of the whole project is through actual involvement and actions make the researchers, companies and selected suppliers...... learn how to improve operations in (hopefully) a win-win like manner through collaboration....

  15. Thermodynamic efficiency of nonimaging concentrators

    Science.gov (United States)

    Shatz, Narkis; Bortz, John; Winston, Roland

    2009-08-01

    The purpose of a nonimaging concentrator is to transfer maximal flux from the phase space of a source to that of a target. A concentrator's performance can be expressed relative to a thermodynamic reference. We discuss consequences of Fermat's principle of geometrical optics. We review étendue dilution and optical loss mechanisms associated with nonimaging concentrators, especially for the photovoltaic (PV) role. We introduce the concept of optical thermodynamic efficiency which is a performance metric combining the first and second laws of thermodynamics. The optical thermodynamic efficiency is a comprehensive metric that takes into account all loss mechanisms associated with transferring flux from the source to the target phase space, which may include losses due to inadequate design, non-ideal materials, fabrication errors, and less than maximal concentration. As such, this metric is a gold standard for evaluating the performance of nonimaging concentrators. Examples are provided to illustrate the use of this new metric. In particular we discuss concentrating PV systems for solar power applications.

  16. Fundamentals and techniques of nonimaging optics for solar energy concentration

    Science.gov (United States)

    Winston, R.; Ogallaher, J. J.

    1980-09-01

    Recent progress in basic research into the theoretical understanding of nonimaging optical systems and their application to the design of practical solar concentration was reviewed. Work was done to extend the previously developed geometrical vector flux formalism with the goal of applying it to the analysis of nonideal concentrators. Both phase space and vector flux representation for traditional concentrators were generated. Understanding of the thermodynamically derived relationship between concentration and cavity effects led to the design of new lossless and low loss concentrators for absorbers with gaps. Quantitative measurements of the response of real collector systems and the distribution of diffuse insolation shows that in most cases performance exceeds predictions in solar applications. These developments led to improved nonimaging solar concentrator designs and applications.

  17. USE CELLULOSE FOR CLEANING CONCENTRATED SUGAR SOLUTIONS

    Directory of Open Access Journals (Sweden)

    N. G. Kul’neva

    2015-01-01

    established that the effect of bleaching decreases with increasing concentration of juice filtration due to high viscosity of the solution. Constructed a nomogram for determining the flow rate of the adsorbent depending on the concentration of the production of furniture, which is of practical importance. Studies have shown that the additional adsorption purification of sugar juice filtration yellow reduces color solutions, to improve the yield and quality of finished products.

  18. Concentrating Solar Power Projects - Planta Solar 20 | Concentrating Solar

    Science.gov (United States)

    Power | NREL 20 This page provides information on Planta Solar 20, a concentrating solar power Solar's Planta Solar 20 (PS20) is a 20-megawatt power tower plant being constructed next to the PS10 tower and increasing incident solar radiation capture will increase net electrical power output by 10

  19. Concentrating Solar Power Projects - Nevada Solar One | Concentrating Solar

    Science.gov (United States)

    Power | NREL Nevada Solar One This page provides information on Nevada Solar One, a concentrating solar power (CSP) project, with data organized by background, participants, and power plant configuration. Acciona Energy's Nevada Solar One is the third largest CSP plant in the world and the first plant

  20. Concentrating Solar Power Projects - Khi Solar One | Concentrating Solar

    Science.gov (United States)

    Power | NREL Khi Solar One This page provides information on Khi Solar One, a concentrating solar power (CSP) project, with data organized by background, parcipants and power plant configuration . Status Date: February 8, 2016 Project Overview Project Name: Khi Solar One Country: South Africa Location

  1. concentrate ratio and rumen ammonia concentration on in situ

    African Journals Online (AJOL)

    The aim of this experiment was to distinguish between the effects of dietary roughage: concentrate ratio and rumen ammonia ... several factors which include the potential rate and extent of degradation of the test feedstuff and the prevailing rate of ... diet effects have be,en designed to examine either the influence of dietary ...

  2. Collaborative Improvement

    DEFF Research Database (Denmark)

    Kaltoft, Rasmus

    -organisational continuous improvement of their performance, relative to that of other EMEs. Developing a collaborative improvement relationship between companies is a protracted and complex process and, according to some surveys, the failure rate is as low as one to three. This failure rate is affected by a whole range...... of factors. The research presented in this thesis was aimed at identifying these factors and investigating their interplay and influence on the progress and success of the development of the collaborative improvement. This thesis presents our findings regarding the factors found, their interplay...

  3. Concentric retinitis pigmentosa: clinicopathologic correlations.

    Science.gov (United States)

    Milam, A H; De Castro, E B; Smith, J E; Tang, W X; John, S K; Gorin, M B; Stone, E M; Aguirre, G D; Jacobson, S G

    2001-10-01

    Progressive concentric (centripetal) loss of vision is one pattern of visual field loss in retinitis pigmentosa. This study provides the first clinicopathologic correlations for this form of retinitis pigmentosa. A family with autosomal dominant concentric retinitis pigmentosa was examined clinically and with visual function tests. A post-mortem eye of an affected 94 year old family member was processed for histopathology and immunocytochemistry with retinal cell specific antibodies. Unrelated simplex/multiplex patients with concentric retinitis pigmentosa were also examined. Affected family members of the eye donor and patients from the other families had prominent peripheral pigmentary retinopathy with more normal appearing central retina, good visual acuity, concentric field loss, normal or near normal rod and cone sensitivity within the preserved visual field, and reduced rod and cone electroretinograms. The eye donor, at age 90, had good acuity and function in a central island. Grossly, the central region of the donor retina appeared thinned but otherwise normal, while the far periphery contained heavy bone spicule pigment. Microscopically the central retina showed photoreceptor outer segment shortening and some photoreceptor cell loss. The mid periphery had a sharp line of demarcation where more central photoreceptors were near normal except for very short outer segments and peripheral photoreceptors were absent. Rods and cones showed abrupt loss of outer segments and cell death at this interface. It is concluded that concentric retinitis pigmentosa is a rare but recognizable phenotype with slowly progressive photoreceptor death from the far periphery toward the central retina. The disease is retina-wide but shows regional variation in severity of degeneration; photoreceptor death is severe in the peripheral retina with an abrupt edge between viable and degenerate photoreceptors. Peripheral to central gradients of unknown retinal molecule(s) may be defective

  4. Improvement of the quality of diabetes control and decrease in the concentrations of AGE-products in patients with type 1 and insulin-treated type 2 diabetes mellitus: results from a 10 year-prospective, population-based survey on the quality of diabetes care in Germany (JEVIN).

    Science.gov (United States)

    Schiel, Ralf; Franke, S; Appel, T; Voigt, U; Ross, I S; Kientsch-Engel, R; Müller, U A; Stein, G

    2004-08-31

    Advanced glycation end (AGE)-products are a complex group of compounds that have been implicated in diabetes related long-term complications. Up to the present only few data exist about serum levels of the AGE-proteins N-epsilon-Carboxymethyllysine (CML) and pentosidine in patients with diabetes mellitus. In the present 10-year, population-based trial of a selection-free cohort of patients with insulin-treated diabetes mellitus, serum CML and pentosidine levels were examined in correlation to the patients' quality of diabetes control and the prevalence of diabetes related long-term complications. Following the reunification of Germany in 1989 the health care system was decentralised. Up to 1994/95 the relative HbA1c (HbA1c/mean normal) of patients with type 1 diabetes increased (1.65 +/- 0.35 versus 1.52 +/- 0.31, p = 0.002). For patients with type 2 diabetes it remained constant (1.75 +/- 0.4 versus 1.78 +/- 0.31, p = 0.669). During the following period (from 1994/95 to 1999/2000) specialised diabetes care, structured treatment and teaching programmes (TTP), intensified insulin therapy and blood glucose self-monitoring for all patients were broadly implemented. This was accompanied by a substantial improvement in the relative HbA1c of both, patients with type 1 (1.48 +/- 0.3, pproduct CML in the sera of patients with type 1 and insulin-treated type 2 diabetes decreased (type 1: 1994/95: 1158.1 +/- 410.0 ng/ml versus 1999/2000: 938.5 +/- 422.4 ng/ml, pimprovement in patients' quality of diabetes control but also a decrease in the concentration of AGE-products. In patients with diabetes mellitus the AGE-products seem to be mainly influenced by the quality of diabetes control. The decline in renal function leads to increased serum pentosidine levels in patients with insulin-treated diabetes mellitus. Thus it seems that in patients with reduced renal function, higher levels may either play a causal role in the development and progression of nephropathy or they are an

  5. Concentrator-solar-cell development

    Science.gov (United States)

    Grenon, L.

    1982-07-01

    A program is described which is a continuation of earlier programs for the development of high-efficiency, low-cost, silicon concentrator solar cells. The base-line process steps and process sequences identified in these earlier contracts were evaluated and specific processes reviewed. In particular, emphasis on the use of Czochralski-grown silicon wafers rather than float-zone wafers were examined. Additionally, a study of the trade-offs between textured and nontextured cells was initiated, and the limits within which the low-cost plated nickel copper metallization can be used in concentrator solar cell applications was identified.

  6. Performance of an absorbing concentrating solar collectors

    International Nuclear Information System (INIS)

    Imadojemu, H.

    1990-01-01

    This paper reports on a comparison of the efficiency of an absorbing fluid parabolic trough concentrating solar collector and a traditional concentrating collector that was made. In the absorbing fluid collector, black liquid flows through a glass tube absorber while the same black liquid flows through a selective black coated copper tube absorber while the same black fluid flows through a selective black coated copper tube absorber in the traditional collector. After a careful study of the properties of available black liquids, a mixture of water and black ink was chosen as the black absorbing medium or transfer fluid. In the black liquid glass collector there is a slightly improved efficiency based on beam radiation as a result of the direct absorption process and an increase in the effective transmittance absorptance. At worst the efficiency of this collector equals that of the traditional concentrating collector when the efficiency is based on total radiation. The collector's reflecting surfaces were made of aluminum sheet, parabolic line focus and with cylindrical receivers. The ease of manufacture and reduced cost per unit energy collected, in addition to the clean and pollution free mode of energy conversion, makes it very attractive

  7. High hydrostatic pressure treatment of porcine oocytes before handmade cloning improves developmental competence and cryosurvival

    DEFF Research Database (Denmark)

    Dupont, Yoko; Lin, Lin; Schmidt, Mette

    2008-01-01

    and cryotolerance of embryos produced by handmade cloning (HMC) after pressure treatment of recipient oocytes. In vitro-matured porcine oocytes were treated with a sublethal hydrostatic pressure of 20 MPa (200 times greater than atmospheric pressure) and recovered for either 1 or 2 h (HHP1 and HHP2 groups......, respectively) before they were used for HMC. After 7 days of in vitro culture, blastocyst rates and mean cell numbers were determined. Randomly selected blastocysts were vitrified with the Cryotop method based on minimum volume cooling procedure. The blastocyst rate was higher in the HHP2 group than...... in the control group (68.2 +/- 4.1% vs. 46.4 +/- 4.2%; p 0.05). Similar mean cell numbers of produced blastocysts were obtained in HHP2 and control groups (56 +/- 4 vs. 49 +/- 5; p > 0.05). Subsequent...

  8. Indoor radon concentration in Poland

    International Nuclear Information System (INIS)

    Mamont-Ciesla, K.; Jagielak, J.; Rosinski, S.W.; Sosinka, A.; Bysiek, M.; Henschke, J.

    1996-01-01

    Preliminary survey of Rn concentration indoors by means of track detectors and y-ray dose rate with the use of TLD in almost 500 homes in selected areas of Poland was performed in the late 1980s. It was concluded that radon contributes 1.16 mSv i.e. about 46 per cent of the total natural environment ionizing radiation dose to the Polish population. Comparison of the average radon concentrations in 4 seasons of a year and in 3 groups of buildings: masonry, concrete and wood, revealed that the ground beneath the building structure is likely the dominant source of radon indoors. Since the National Atomic Energy Agency in its regulations of 1988-03-31 set up the permissible limit of the equilibrium equivalent concentration of radon in new buildings (equal 100 Bq/m3), the nation-scale survey project for radon in buildings has been undertaken. These regulations were supposed to take effect in 1995-01-01. The project has 3 objectives: to estimate the radiation exposure due to radon daughters received by Polish population to identify radon-prone areas in Poland to investigate dependence of the indoor radon concentrations on such parameters as: type of construction material, presence (or absence) of cellar under the building, number of floor

  9. Uranium concentrations in human bone

    International Nuclear Information System (INIS)

    Schlenker, R.A.; Oltman, B.G.

    1981-01-01

    The uranium concentration in bone from an individual injected with 239 Pu has been determined, using the fission-track method. The data are consistent with those reported about 10 years ago by Welford and Baird for New York City area residents and by Hamilton in England. They are at variance with the more recent data of Welford et al

  10. Error exponents for entanglement concentration

    International Nuclear Information System (INIS)

    Hayashi, Masahito; Koashi, Masato; Matsumoto, Keiji; Morikoshi, Fumiaki; Winter, Andreas

    2003-01-01

    Consider entanglement concentration schemes that convert n identical copies of a pure state into a maximally entangled state of a desired size with success probability being close to one in the asymptotic limit. We give the distillable entanglement, the number of Bell pairs distilled per copy, as a function of an error exponent, which represents the rate of decrease in failure probability as n tends to infinity. The formula fills the gap between the least upper bound of distillable entanglement in probabilistic concentration, which is the well-known entropy of entanglement, and the maximum attained in deterministic concentration. The method of types in information theory enables the detailed analysis of the distillable entanglement in terms of the error rate. In addition to the probabilistic argument, we consider another type of entanglement concentration scheme, where the initial state is deterministically transformed into a (possibly mixed) final state whose fidelity to a maximally entangled state of a desired size converges to one in the asymptotic limit. We show that the same formula as in the probabilistic argument is valid for the argument on fidelity by replacing the success probability with the fidelity. Furthermore, we also discuss entanglement yield when optimal success probability or optimal fidelity converges to zero in the asymptotic limit (strong converse), and give the explicit formulae for those cases

  11. Particle interactions in concentrated suspensions

    International Nuclear Information System (INIS)

    Mondy, L.A.; Graham, A.L.; Abbott, J.R.; Brenner, H.

    1993-01-01

    An overview is presented of research that focuses on slow flows of suspensions in which colloidal and inertial effects are negligibly small. The authors describe nuclear magnetic resonance imaging experiments to quantitatively measure particle migration occurring in concentrated suspensions undergoing a flow with a nonuniform shear rate. These experiments address the issue of how the flow field affects the microstructure of suspensions. In order to understand the local viscosity in a suspension with such a flow-induced, spatially varying concentration, one must know how the viscosity of a homogeneous suspension depends on such variables as solids concentration and particle orientation. The authors suggest the technique of falling ball viscometry, using small balls, as a method to determine the effective viscosity of a suspension without affecting the original microstructure significantly. They also describe data from experiments in which the detailed fluctuations of a falling ball's velocity indicate the noncontinuum nature of the suspension and may lead to more insights into the effects of suspension microstructure on macroscopic properties. Finally, they briefly describe other experiments that can be performed in quiescent suspensions (in contrast to the use of conventional shear rotational viscometers) in order to learn more about boundary effects in concentrated suspensions

  12. Freeform optics for photovoltaic concentration

    OpenAIRE

    Benitez Gimenez, Pablo; Miñano Dominguez, Juan Carlos

    2012-01-01

    Freeform surfaces are the key of the state-of-the-art nonimaging optics to solve the challenges in concentration photovoltaics. Different families (FK, XR, FRXI) will be presented, based on the SMS 3D design method and Köhler homogenization.

  13. Cesium Concentration in MCU Solvent

    International Nuclear Information System (INIS)

    Walker, D

    2006-01-01

    During Modular Caustic-Side Solvent Extraction (CSSX) Unit (MCU) operations, Cs-137 concentrations in product streams will vary depending on the location in the process and on the recent process conditions. Calculations of cesium concentrations under a variety of operating conditions reveal the following: (1) Under nominal operations with salt solution feed containing 1.1 Ci Cs-137 per gallon, the maximum Cs-137 concentration in the process will occur in the strip effluent (SE) and equal 15-16.5 Ci/gal. (2) Under these conditions, the majority of the solvent will contain 0.005 to 0.01 Ci/gal, with a limited portion of the solvent in the contactor stages containing ∼4 Ci/gal. (3) When operating conditions yield product near 0.1 Ci Cs-137/gal in the decontaminated salt solution (DSS), the SE cesium concentration will be the same or lower than in nominal operations, but majority of the stripped solvent will increase to ∼2-3 Ci/gal. (4) Deviations in strip and waste stream flow rates cause the largest variations in cesium content: (a) If strip flow rates deviate by -30% of nominal, the SE will contain ∼23 Ci/gal, although the cesium content of the solvent will increase to only 0.03 Ci/gal; (b) If strip flow rate deviates by -77% (i.e., 23% of nominal), the SE will contain 54 Ci/gal and solvent will contain 1.65 Ci/gal. At this point, the product DSS will just reach the limit of 0.1 Ci/gal, causing the DSS gamma monitors to alarm; and (c) Moderate (+10 to +30%) deviations in waste flow rate cause approximately proportional increases in the SE and solvent cesium concentrations. Recovery from a process failure due to poor cesium stripping can achieve any low cesium concentration required. Passing the solvent back through the contactors while recycling DSS product will produce a ∼70% reduction during one pass through the contactors (assuming the stripping D value is no worse than 0.36). If the solvent is returned to the solvent hold tank (containing additional

  14. Market Concentration Rate and Market Performance of China’s Swine Industry

    Institute of Scientific and Technical Information of China (English)

    Jia ZHANG; Yucheng HE

    2016-01-01

    Empirical study on market concentration rate and market performance of China’s Swine Industry indicates that higher market concentration rate brings higher overall performance of swine industry. There exists no obvious causal relation between market concentration rate and market performance,but market performance is highly correlated with market concentration rate. The improvement in performance of swine industry is dependent on further optimization of market concentration rate and other factors.

  15. Thiosulphate leaching of gold-, silver-, copper flotation concentrates

    International Nuclear Information System (INIS)

    Samikhov, Sh.R.; Zinchenko, Z.A.

    2015-01-01

    Present article is devoted to thiosulphate leaching of gold-, silver-, copper flotation concentrates. For the purpose to improve the process of thiosulphate leaching the ore samples were calcined at temperature 600 ℃ during two hours. During the calcination process of gold-sulphide ores and concentrates the minerals pyrite and arsenopyrite oxidize which lead to opening of gold contains in them. It was defined that thiosulphate leaching can be recommended as an alternative to cyanic process.

  16. Review of pump suction reducer selection: Eccentric or concentric reducers

    OpenAIRE

    Mahaffey, R M; van Vuuren, S J

    2014-01-01

    Eccentric reducers are traditionally recommended for the pump suction reducer fitting to allow for transportation of air through the fitting to the pump. The ability of a concentric reducer to provide an improved approach flow to the pump while still allowing air to be transported through the fitting is investigated. Computational fluid dynamics (CFD) were utilised to analyse six concentric and six eccentric reducer geometries at four different inlet velocities to determine the flow velocity ...

  17. Concentrations: Recent Developments in Italy

    Directory of Open Access Journals (Sweden)

    Claudio Tesauro

    2015-10-01

    Full Text Available Recent Italian developments in antitrust concentrations was the topic I was assigned to address at the conference held on 23 April to celebrate the first anniversary of the Italian Antitrust Review. What is immediately clear is that far fewer concentrations have been notified over the last few years. This is probably due to the economic crisis, which caused a reduction in corporate transactions; but also the changes to the turnover thresholds for notification seem to have had a significant impact. Consequently, an interesting debate is underway regarding the need for further changes the threshold system. Moreover, the drastic market developments and the subsequent increased number of decisions to revise remedies should also be further examined. These two issues are the subject of this paper.

  18. Cylindrical acoustic levitator/concentrator

    Science.gov (United States)

    Kaduchak, Gregory; Sinha, Dipen N.

    2002-01-01

    A low-power, inexpensive acoustic apparatus for levitation and/or concentration of aerosols and small liquid/solid samples having particulates up to several millimeters in diameter in air or other fluids is described. It is constructed from a commercially available, hollow cylindrical piezoelectric crystal which has been modified to tune the resonance frequency of the breathing mode resonance of the crystal to that of the interior cavity of the cylinder. When the resonance frequency of the interior cylindrical cavity is matched to the breathing mode resonance of the cylindrical piezoelectric transducer, the acoustic efficiency for establishing a standing wave pattern in the cavity is high. The cylinder does not require accurate alignment of a resonant cavity. Water droplets having diameters greater than 1 mm have been levitated against the force of gravity using; less than 1 W of input electrical power. Concentration of aerosol particles in air is also demonstrated.

  19. Multijunction Photovoltaic Technologies for High-Performance Concentrators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, R.; Symko-Davies, M.

    2006-05-01

    Multijunction solar cells provide high-performance technology pathways leading to potentially low-cost electricity generated from concentrated sunlight. The National Center for Photovoltaics at the National Renewable Energy Laboratory has funded different III-V multijunction solar cell technologies and various solar concentration approaches. Within this group of projects, III-V solar cell efficiencies of 41% are close at hand and will likely be reported in these conference proceedings. Companies with well-developed solar concentrator structures foresee installed system costs of $3/watt--half of today's costs--within the next 2 to 5 years as these high-efficiency photovoltaic technologies are incorporated into their concentrator photovoltaic systems. These technology improvements are timely as new large-scale multi-megawatt markets, appropriate for high performance PV concentrators, open around the world.

  20. BASIC FACTORS OF MARKET CONCENTRATION

    OpenAIRE

    V. Fyliuk

    2013-01-01

    The paper systemizes factors which reinforce trends towards market concentration in all economic systems. These factors include factors related to the general changes in economic environment such as globalization of the world economy, state structural and taxation policies, cycle of economic development and changes in consumer demand. They also include factors related to competition (intensification of competition, companies’ desire to monopolize market and present market structure) and scien...

  1. Experience in handling concentrated tritium

    International Nuclear Information System (INIS)

    Holtslander, W.J.

    1985-12-01

    The notes describe the experience in handling concentrated tritium in the hydrogen form accumulated in the Chalk River Nuclear Laboratories Tritium Laboratory. The techniques of box operation, pumping systems, hydriding and dehydriding operations, and analysis of tritium are discussed. Information on the Chalk River Tritium Extraction Plant is included as a collection of reprints of papers presented at the Dayton Meeting on Tritium Technology, 1985 April 30 - May 2

  2. Arsenic concentrations in Chinese coals

    International Nuclear Information System (INIS)

    Wang Mingshi; Zheng Baoshan; Wang Binbin; Li Shehong; Wu Daishe; Hu Jun

    2006-01-01

    The arsenic concentrations in 297 coal samples were collected from the main coal-mines of 26 provinces in China were determined by molybdenum blue coloration method. These samples were collected from coals that vary widely in coal rank and coal-forming periods from the five main coal-bearing regions in China. Arsenic content in Chinese coals range between 0.24 to 71 mg/kg. The mean of the concentration of Arsenic is 6.4 ± 0.5 mg/kg and the geometric mean is 4.0 ± 8.5 mg/kg. The level of arsenic in China is higher in northeastern and southern provinces, but lower in northwestern provinces. The relationship between arsenic content and coal-forming period, coal rank is studied. It was observed that the arsenic contents decreases with coal rank in the order: Tertiary > Early Jurassic > Late Triassic > Late Jurassic > Middle Jurassic > Late Permian > Early Carboniferous > Middle Carboniferous > Late Carboniferous > Early Permian; It was also noted that the arsenic contents decrease in the order: Subbituminous > Anthracite > Bituminous. However, compared with the geological characteristics of coal forming region, coal rank and coal-forming period have little effect on the concentration of arsenic in Chinese coal. The average arsenic concentration of Chinese coal is lower than that of the whole world. The health problems in China derived from in coal (arsenism) are due largely to poor local life-style practices in cooking and home heating with coal rather than to high arsenic contents in the coal

  3. REM-containing silicate concentrates

    International Nuclear Information System (INIS)

    Pavlov, V F; Shabanova, O V; Pavlov, I V; Pavlov, M V; Shabanov, A V

    2016-01-01

    A new method of advanced complex processing of ores containing rare-earth elements (REE) is proposed to obtain porous X-ray amorphous aluminosilicate material with a stable chemical composition which concentrates oxides of rare-earth metals (REM). The ferromanganese oxide ores of Chuktukon deposit (Krasnoyarsk Region, RF) were used for the experiment. The obtained aluminosilicate material is appropriate for treatment with 5 - 15% solutions of mineral acids to leach REM. (paper)

  4. REM-containing silicate concentrates

    Science.gov (United States)

    Pavlov, V. F.; Shabanova, O. V.; Pavlov, I. V.; Pavlov, M. V.; Shabanov, A. V.

    2016-01-01

    A new method of advanced complex processing of ores containing rare-earth elements (REE) is proposed to obtain porous X-ray amorphous aluminosilicate material with a stable chemical composition which concentrates oxides of rare-earth metals (REM). The ferromanganese oxide ores of Chuktukon deposit (Krasnoyarsk Region, RF) were used for the experiment. The obtained aluminosilicate material is appropriate for treatment with 5 - 15% solutions of mineral acids to leach REM.

  5. Concentration of light rare earths process by amoniacal precipitation

    International Nuclear Information System (INIS)

    Aguilera, Y.; Rapado, M.; Consuegra, R.

    1996-01-01

    A procedure for the separation and concentration of light rare earths using a mixture of ammonia and water was developed. As a result technical concentrates of rare earths were obtained and the physical separation in the filtration step was improved. The filtration parameters (cake resistance r 0 and filtration web resistance R) were obtained for this process being they 5,5.10 11 cm/g and 3,4.10 13 cm -1 respectively. The proposed technology concentrates (Ce, La and Nd) with purities ranging from: 85-90 %, 85-87 % and 42-65 % respectively in only one precipitation step

  6. Pressure leaching of chalcopyrite concentrate

    Science.gov (United States)

    Aleksei, Kritskii; Kirill, Karimov; Stanislav, Naboichenko

    2018-05-01

    The results of chalcopyrite concentrate processing using low-temperature and high-temperature sulfuric acid pressure leaching are presented. A material of the following composition was used, 21.5 Cu, 0.1 Zn, 0.05 Pb, 0.04 Ni, 26.59 S, 24.52 Fe, 16.28 SiO2 (in wt.%). The influence of technological parameters on the degree of copper and iron extraction into the leach solution was studied in the wide range of values. The following conditions were suggested as the optimal for the high-temperature pressure leaching: t = 190 °C, PO2 = 0.5 MPa, CH2SO4 = 15 g/L, L:S = 6:1. At the mentioned parameters, it is possible to extract at least 98% Cu from concentrate into the leaching solution during 100 minutes. The following conditions were suggested as optimal for the low-temperature pressure leaching: t = 105 °C, PO2 = 1.3-1.5 MPa, CH2SO4 = 90 g/L, L:S = 10:1. At the mentioned parameters, it is possible to extract up to 83% Cu from the concentrate into the leach solution during 300-360 minutes.

  7. Improving Patient Safety: Improving Communication.

    Science.gov (United States)

    Bittner-Fagan, Heather; Davis, Joshua; Savoy, Margot

    2017-12-01

    Communication among physicians, staff, and patients is a critical element in patient safety. Effective communication skills can be taught and improved through training and awareness. The practice of family medicine allows for long-term relationships with patients, which affords opportunities for ongoing, high-quality communication. There are many barriers to effective communication, including patient factors, clinician factors, and system factors, but tools and strategies exist to address these barriers, improve communication, and engage patients in their care. Use of universal precautions for health literacy, appropriate medical interpreters, and shared decision-making are evidence-based tools that improve communication and increase patient safety. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

  8. Luminescent solar concentrators utilizing stimulated emission.

    Science.gov (United States)

    Kaysir, Md Rejvi; Fleming, Simon; MacQueen, Rowan W; Schmidt, Timothy W; Argyros, Alexander

    2016-03-21

    Luminescent solar concentrators (LSCs) are an emerging technology that aims primarily to reduce the cost of solar energy, with great potential for building integrated photovoltaic (PV) structures. However, realizing LSCs with commercially viable efficiency is currently hindered by reabsorption losses. Here, we introduce an approach to reducing reabsorption as well as improving directional emission in LSCs by using stimulated emission. Light from a seed laser (potentially an inexpensive laser diode) passes through the entire area of the LSC panel, modifying the emission spectrum of excited dye molecules such that it is spectrally narrower, at wavelengths that minimize reabsorption to allow net gain in the system, and directed towards a small PV cell. A mathematical model, taking into account thermodynamic considerations, of such a system is presented which identifies key parameters and allows evaluation in terms of net effective output power.

  9. Plasma leptin concentration in donkeys.

    Science.gov (United States)

    Díez, E; López, I; Pérez, C; Pineda, C; Aguilera-Tejero, E

    2012-01-01

    Donkeys appear to be more predisposed than large breed horses to suffer from hyperlipemia. The reason for that predisposition is unknown but anorexia is a consistent feature of the disease. Leptin, a protein synthesized in fat tissue, is one of the major inhibitors of appetite in mammals. We hypothesized that donkeys could have elevated plasma leptin concentrations compared to horses. Blood samples were obtained from 50 donkeys for measurement of leptin, triglycerides (TGs), glucose, and insulin. Glucose/insulin ratio, modified insulin to glucose ratio, and reciprocal of the square root of insulin were calculated. Based on their body condition score (BCS), donkeys were classified as lean (n = 18), normal (n = 16), or overweight (n = 16). The results were compared with reference values from our laboratory and with a group of horses (n = 25) used as an internal control. Values of both leptin and TGs in donkeys were above the horse reference range and also significantly higher than those of the control horses: leptin (11.2 ± 1.7 versus 5.8 ± 0.5 µg/L, p donkeys had leptin (19.3 ± 2.9 µg/L) and TG (1.3 ± 0.2 mmol/L) concentrations that were significantly (p donkeys. A significant positive correlation (p Donkeys have higher plasma leptin concentrations than horses and leptin is correlated with BCS.

  10. Factors influencing erythrocyte choline concentrations.

    Science.gov (United States)

    Miller, B L; Jenden, D J; Tang, C; Read, S

    1989-01-01

    Choline concentrations in human erythrocytes increase after freezing and thawing, during incubation in Krebs-phosphate for 30 min or on storage at 0 degrees C for 3-24 hr. The increase is prevented by protein precipitation by 10% perchloric acid, 10% zinc hydroxide, 10% sodium tungstate or boiling in water. It is not prevented by EDTA (10 mM) and is increased by oleate (5 mM). We suggest that the increase is due to the action of phospholipase D on erythrocyte phospholipids.

  11. Concentrated solar thermal power - Now

    Energy Technology Data Exchange (ETDEWEB)

    Aringhoff, R.; Brakmann, G. [Solar Thermal Power Industry Association ESTIA, Avenue de la Fauconnerie 73, 1170 Brussels (Belgium); Geyer, M. [IEA SolarPACES Implementing Agreement, Avenida de la Paz 51, 04720 Aguadulce, Almeria (Spain); Teske, S. [Greenpeace International, Ottho Heldringstraat 5, 1066 AZ Amsterdam (Netherlands)

    2005-09-15

    This report demonstrates that there are no technical, economic or resource barriers to supplying 5% of the world's electricity needs from solar thermal power by 2040. It is written as practical blueprint to improve understanding of the solar thermal contribution to the world energy supply.

  12. Concentrated solar thermal power - Now

    Energy Technology Data Exchange (ETDEWEB)

    Aringhoff, R.; Brakmann, G. [Solar Thermal Power Industry Association ESTIA, Avenue de la Fauconnerie 73, 1170 Brussels (Belgium); Geyer, M. [IEA SolarPACES Implementing Agreement, Avenida de la Paz 51, 04720 Aguadulce, Almeria (Spain); Teske, S. [Greenpeace International, Ottho Heldringstraat 5, 1066 AZ Amsterdam (Netherlands)

    2005-09-15

    This report demonstrates that there are no technical, economic or resource barriers to supplying 5% of the world's electricity needs from solar thermal power by 2040. It is written as practical blueprint to improve understanding of the solar thermal contribution to the world energy supply.

  13. Armoring confined bubbles in concentrated colloidal suspensions

    Science.gov (United States)

    Yu, Yingxian; Khodaparast, Sepideh; Stone, Howard

    2016-11-01

    Encapsulation of a bubble with microparticles is known to significantly improve the stability of the bubble. This phenomenon has recently gained increasing attention due to its application in a variety of technologies such as foam stabilization, drug encapsulation and colloidosomes. Nevertheless, the production of such colloidal armored bubble with controlled size and particle coverage ratio is still a great challenge industrially. We study the coating process of a long air bubble by microparticles in a circular tube filled with a concentrated microparticles colloidal suspension. As the bubble proceeds in the suspension of particles, a monolayer of micro-particles forms on the interface of the bubble, which eventually results in a fully armored bubble. We investigate the phenomenon that triggers and controls the evolution of the particle accumulation on the bubble interface. Moreover, we examine the effects of the mean flow velocity, the size of the colloids and concentration of the suspension on the dynamics of the armored bubble. The results of this study can potentially be applied to production of particle-encapsulated bubbles, surface-cleaning techniques, and gas-assisted injection molding.

  14. Concentrated photovoltaics, a case study

    Directory of Open Access Journals (Sweden)

    Antonini Piergiorgio

    2014-01-01

    Full Text Available Concentrated Photovoltaics (CPV, once a niche technology, has now reached the maturity and reliability for large scale power generation. Especially in regions where temperatures are very high, the use of high efficiency triple junction solar cells with concentrating optics allows stable energy yield. Thus CPV can be seen as complementary and not in concurrence with silicon photovoltaics. The state of the art, the advantages and limitations of this technology will be shown. Among the main advantages of CPV is the possibility of a much higher energy supply, when compared to silicon photovoltaics, both comparing CPV and silicon with same area or the same installed power. The use of recycled and recyclable materials allows a more environmentally friendly production. The possibility to couple CPV with desalination facilities, energy storage will be analysed. As an example a case study of a CPV installation in Northern Italy is discussed. Here the use of mature technologies, derived from automotive and lighting sectors resulted in a simple and efficient module.

  15. Technology Roadmaps: Concentrating Solar Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The emerging technology known as concentrating solar power, or CSP, holds much promise for countries with plenty of sunshine and clear skies. Its electrical output matches well the shifting daily demand for electricity in places where airconditioning systems are spreading. When backed up by thermal storage facilities and combustible fuel, it offers utilities electricity that can be dispatched when required, enabling it to be used for base, shoulder and peak loads. Within about one to two decades, it will be able to compete with coal plants that emit high levels of CO2. The sunniest regions, such as North Africa, may be able to export surplus solar electricity to neighbouring regions, such as Europe, where demand for electricity from renewable sources is strong. In the medium-to-longer term, concentrating solar facilities can also produce hydrogen, which can be blended with natural gas, and provide low-carbon liquid fuels for transport and other end-use sectors. For CSP to claim its share of the coming energy revolution, concerted action is required over the next ten years by scientists, industry, governments, financing institutions and the public. This roadmap is intended to help drive these indispensable developments.

  16. Concentration - dose - risk computer code

    International Nuclear Information System (INIS)

    Frujinoiu, C.; Preda, M.

    1997-01-01

    Generally, the society is less willing in promoting remedial actions in case of low level chronic exposure situations. Radon in dwellings and workplaces is a case connected to chronic exposure. Apart from radon, the solely source on which the international community agreed for setting action levels, there are other numerous sources technically modified by man that can generate chronic exposure. Even if the nuclear installations are the most relevant, we are surrounded by 'man-made radioactivity' such as: mining industry, coal-fired power plants and fertilizer industry. The operating of an installation even within 'normal limits' could generate chronic exposure due to accumulation of the pollutants after a definite time. This asymptotic proclivity to a constant level define a steady-state concentration that represents a characteristic of the source's presence in the environment. The paper presents a methodology and a code package that derives sequentially the steady-state concentration, doses, detriments, as well as the costs of the effects of installation operation in a given environment. (authors)

  17. Platelet concentration in platelet concentrates and periodontal regeneration-unscrambling the ambiguity

    Directory of Open Access Journals (Sweden)

    A Suchetha

    2015-01-01

    Full Text Available Context: Platelet-rich-plasma (PRP and Platelet-rich-fibrin (PRF are extensively used autologous platelet concentrates in periodontal regeneration, and PRF has a better efficacy as compared to PRP. The rationale for this difference has often been attributed to the difference in the structure of the fibrin matrix. However, the effect of concentration of platelets on the regenerative potential of these concentrates is obscure. Aims: The study was conducted to evaluate and compare, clinically and radiographically, the efficacy of PRF and PRP in the treatment of periodontal endosseous defects and to assess the effect of platelet concentration on periodontal regeneration. Materials and Methods: Twenty intrabony defects were selected and divided into two groups randomly by the coin toss method. Group I received PRP and Group II subjects were treated with PRF. The platelet counts in PRP and PRF were analyzed. Clinical and radiological parameters were assessed at baseline and 3, 6, and 9 months postoperatively. Statistical Analysis: Kruskal–Wallis Chi-square test, Wilcoxon signed rank test, t-test, and Spearman's rank correlation were used for statistical analysis of data. Results: There was statistically significant improvement in all the parameters in the two groups except in relation to gingival recession. There was a statistically significant difference between the platelet count in Group I and Group II (P = 0.002. Conclusion: PRP and PRF appear to have nearly comparable effects in terms of periodontal regeneration. The concentration of platelets appears to play a paradoxical role in regeneration. The regenerative potential of platelets appears to be optimal within a limited range.

  18. Improved netting

    International Nuclear Information System (INIS)

    Bramley, A.; Clabburn, R.J.T.

    1976-01-01

    A method is described for producing netting composed of longitudinal and transverse threads of irradiation cross linked thermoplastic material, the threads being joined together at their crossings by moulded masses of cross linked thermoplastic material. The thread may be formed of polyethylene filaments, subjected to a radiation dose of 15 to 25 MR. The moulding can be conducted at 245 0 to 260 0 C or higher. The product is claimed to be an improved quality of netting, with bonds of increased strength between crossing threads. (U.K.)

  19. Validation of predicted exponential concentration profiles of chemicals in soils

    International Nuclear Information System (INIS)

    Hollander, Anne; Baijens, Iris; Ragas, Ad; Huijbregts, Mark; Meent, Dik van de

    2007-01-01

    Multimedia mass balance models assume well-mixed homogeneous compartments. Particularly for soils, this does not correspond to reality, which results in potentially large uncertainties in estimates of transport fluxes from soils. A theoretically expected exponential decrease model of chemical concentrations with depth has been proposed, but hardly tested against empirical data. In this paper, we explored the correspondence between theoretically predicted soil concentration profiles and 84 field measured profiles. In most cases, chemical concentrations in soils appear to decline exponentially with depth, and values for the chemical specific soil penetration depth (d p ) are predicted within one order of magnitude. Over all, the reliability of multimedia models will improve when they account for depth-dependent soil concentrations, so we recommend to take into account the described theoretical exponential decrease model of chemical concentrations with depth in chemical fate studies. In this model the d p -values should estimated be either based on local conditions or on a fixed d p -value, which we recommend to be 10 cm for chemicals with a log K ow > 3. - Multimedia mass model predictions will improve when taking into account depth dependent soil concentrations

  20. Concentration device for leak liquids

    International Nuclear Information System (INIS)

    Matsumoto, Kaname; Matsuda, Ken; Takabori, Ken-ichi.

    1987-01-01

    Purpose: To improve radioactivity recovery and volume-reducing rates, as well as enable safety and easy handling for leak liquids resulted from reptures in coolant circuits. Constitution: The device of the invention comprises an evaporation vessel filled with leak fluids to a predetermined level, an airtight vessel disposed in the evaporation vessel containing hydrophilic porous material partially immersed in the leak fluids and means for heating the hydrophilic material. In this device, leak liquids are absorbed in the hydrophilic porous material, a great amount of water is evaporated from the outer surface of the hydrophilic porous material exposed above the liquid surface, and salts and radioactive material are remained on the inside and the outer surface of the porous material. The evaporated water content is condensated and recovered in a cooler and the remaining salts, etc. are discarded together with the porous material. The volume-reducing property can be improved by constituting the porous material with burnable material. (Takahashi, M.)

  1. Dose concentration and dose verification for radiotherapy of cancer

    International Nuclear Information System (INIS)

    Maruyama, Koichi

    2005-01-01

    The number of cancer treatments using radiation therapy is increasing. The background of this increase is the accumulated fact that the number of successful cases is comparative to or even better than surgery for some types of cancer due to the improvement in irradiation technology and radiation planning technology. This review describes the principles and technology of radiation therapy, its characteristics, particle therapy that improves the dose concentration, its historical background, the importance of dose concentration, present situation and future possibilities. There are serious problems that hinder the superior dose concentration of particle therapy. Recent programs and our efforts to solve these problems are described. A new concept is required to satisfy the notion of evidence based medicine, i.e., one has to develop a method of dose verification, which is not yet available. This review is for researchers, medical doctors and radiation technologists who are developing this field. (author)

  2. Global variability of cloud condensation nuclei concentrations

    Science.gov (United States)

    Makkonen, Risto; Krüger, Olaf

    2017-04-01

    Atmospheric aerosols can influence cloud optical and dynamical processes by acting as cloud condensation nuclei (CCN). Globally, these indirect aerosol effects are significant to the radiative budget as well as a source of high uncertainty in anthropogenic radiative forcing. While historically many global climate models have fixed CCN concentrations to a certain level, most state-of-the-art models calculate aerosol-cloud interactions with sophisticated methodologies based on interactively simulated aerosol size distributions. However, due to scarcity of atmospheric observations simulated global CCN concentrations remain poorly constrained. Here we assess global CCN variability with a climate model, and attribute potential trends during 2000-2010 to changes in emissions and meteorological fields. Here we have used ECHAM5.5-HAM2 with model M7 microphysical aerosol model. The model has been upgraded with a secondary organic aerosol (SOA) scheme including ELVOCs. Dust and sea salt emissions are calculated online, based on wind speed and hydrology. Each experiment is 11 years, analysed after a 6-month spin-up period. The MODIS CCN product (Terra platform) is used to evaluate model performance throughout 2000-2010. While optical remote observation of CCN column includes several deficiencies, the products serves as a proxy for changes during the simulation period. In our analysis we utilize the observed and simulated vertical column integrated CCN concentration, and limit our analysis only over marine regions. Simulated annual CCN column densities reach 2ṡ108 cm-2 near strong source regions in central Africa, Arabian Sea, Bay of Bengal and China sea. The spatial concentration gradient in CCN(0.2%) is steep, and column densities drop to coasts. While the spatial distribution of CCN at 0.2% supersaturation is closer to that of MODIS proxy, as opposed to 1.0% supersaturation, the overall column integrated CCN are too low. Still, we can compare the relative response of CCN

  3. Capillary concentrators for synchrotron radiation beamlines

    International Nuclear Information System (INIS)

    Heald, S.M.; Brewe, D.L.; Kim, K.H.; Brown, F.C.; Barg, B.; Stern, E.A.

    1996-01-01

    Capillary concentrators condense x-rays by multiple reflections down a gradually tapering capillary. They can provide sub-micron beam spots, and are promising candidates for use in the next generation x-ray microprobe beamlines. The weak energy dependence of their properties make them especially useful for energy scanning applications such as micro-XAFS. This paper examines the potential performance of capillary optics for an x-ray microprobe, as well as some practical issues such as fabrication and alignment. Best performance at third generation sources requires long capillaries, and the authors have been using fiber optics techniques to fabricate capillaries up to one meter in length. The performance of shorter (less than about 0.5 m) capillaries has often been found to agree well with theoretical calculations, indicating the inner surface is a high quality x-ray reflector. These capillaries have been tested at the NSLS for imaging and micro-XAFS down to 2.6 microm resolution with excellent results. On an unfocused bend magnet line flux density approaching 10 6 ph/sec/microm 2 has been achieved. While nearly optimum profiles have been achieved for longer capillaries, the results have been disappointing, and alignment problems are suspected. The dramatic improvement in performance possible at third generation synchrotrons such as the APS is discussed along with improvements possible by using the capillaries in conjunction with coupling optics

  4. Freeze concentration of lime juice

    Directory of Open Access Journals (Sweden)

    Ampawan Tansakul

    2008-11-01

    Full Text Available The main objective of this research was to study the effects of processing conditions, i.e. cooling medium temperature (-6, -12 and -18C and scraper blade rotational speed (50, 100 and 150 rpm on the freeze concentration of lime juice. The initial soluble solid content of lime juice was 7.6 Brix. Results showed that soluble solid content of lime juice increased as cooling medium temperature decreased while scraper blade rotational speed increased. It was also found that the processing condition with -18˚C cooling medium temperature and 150 rpm rotational speed of the scraper blade was the best among all studied conditions, although the loss of the soluble solids with ice crystals during ice separation was relatively high at 35%.

  5. Aquatic respiration rate measurements at low oxygen concentrations.

    Directory of Open Access Journals (Sweden)

    Moritz Holtappels

    Full Text Available Despite its huge ecological importance, microbial oxygen respiration in pelagic waters is little studied, primarily due to methodological difficulties. Respiration measurements are challenging because of the required high resolution of oxygen concentration measurements. Recent improvements in oxygen sensing techniques bear great potential to overcome these limitations. Here we compare 3 different methods to measure oxygen consumption rates at low oxygen concentrations, utilizing amperometric Clark type sensors (STOX, optical sensors (optodes, and mass spectrometry in combination with (18-18O2 labeling. Oxygen concentrations and consumption rates agreed well between the different methods when applied in the same experimental setting. Oxygen consumption rates between 30 and 400 nmol L(-1 h(-1 were measured with high precision and relative standard errors of less than 3%. Rate detection limits in the range of 1 nmol L(-1 h(-1 were suitable for rate determinations in open ocean water and were lowest at the lowest applied O2 concentration.

  6. Performance of planar heterojunction perovskite solar cells under light concentration

    Directory of Open Access Journals (Sweden)

    Aaesha Alnuaimi

    2016-11-01

    Full Text Available In this work, we present 2D simulation of planar heterojunction perovskite solar cells under high concentration using physics-based TCAD. The performance of planar perovskite heterojunction solar cells is examined up to 1000 suns. We analyze the effect of HTM mobility and band structure, surface recombination velocities at interfaces and the effect of series resistance under concentrated light. The simulation results revealed that the low mobility of HTM material limits the improvement in power conversation efficiency of perovskite solar cells under concentration. In addition, large band offset at perovskite/HTM interface contributes to the high series resistance. Moreover, losses due to high surface recombination at interfaces and the high series resistance deteriorate significantly the performance of perovskite solar cells under concentration.

  7. Effect of Limited Hydrolysis on Traditional Soy Protein Concentrate

    Directory of Open Access Journals (Sweden)

    Mirjana B. Pesic

    2006-09-01

    Full Text Available The influence of limited proteolysis of soy protein concentrate on proteinextractability, the composition of the extractable proteins, their emulsifying properties andsome nutritional properties were investigated. Traditional concentrate (alcohol leachedconcentrate was hydrolyzed using trypsin and pepsin as hydrolytic agents. Significantdifferences in extractable protein composition between traditional concentrate and theirhydrolysates were observed by polyacrylamide gel electrophoresis (PAGE and by SDSPAGE.All hydrolysates showed better extractability than the original protein concentrate,whereas significantly better emulsifying properties were noticed at modified concentratesobtained by trypsin induced hydrolysis. These improved properties are the result of twosimultaneous processes, dissociation and degradation of insoluble alcohol-induced proteinaggregates. Enzyme induced hydrolysis had no influence on trypsin-inibitor activity, andsignificantly reduced phytic acid content.

  8. Techniques for Improving Spelling Performance.

    Science.gov (United States)

    Saylor, Paul

    Improving spelling performance of college students is a question of insuring that the correct information is in long-term memory and readily retrievable. Any system of spelling instruction should recognize the capacity limits of the sensory register and short-term memory; provide for identification of and concentration on the distinctive features…

  9. IMPROVING OF ANION EXCHANGERES REGENERATION

    Directory of Open Access Journals (Sweden)

    Muzher M. Ibrahim

    2013-05-01

    Full Text Available Inthis study, Different basis [NaOH and KOH] of variable concentration are usedto reactivate Anion exchangers employing different schemes .The Laboratoryresults showed large improvement in efficiency of these exchangers ( i.eoperating time was increased from 12 to 42 hours .The results of this work showed that the environmentalload (waste water can be reduced greatly when using the proposed regenerationscheme .

  10. Process improvement for alcohol manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Keo, L J

    1965-01-01

    K. claims to have isolated a superior yeast for blackstrap molasses fermentation into alcohol at a concentration of 20% sugar instead of the normal 12% in diluted molasses on a commercial scale. Further improvement of the product was effected by removal of aldehyde by distillation and impurities by oxidation. Flow diagrams are presented with details of each stage.

  11. The concentration of retail in Poland

    Directory of Open Access Journals (Sweden)

    Michał Gazdecki

    2010-01-01

    Full Text Available The article discusses the processes of concentration taking place in retail in Poland. In spite of strong concentration processes, which took place after 2000, Poland still remains a country of dispersed retail structure. In the nearest years we can expect capital concentration (mainly takeovers in modern trade and contract concentration (for example, merchants’ societies in traditional trade.

  12. Family-Concentrated Ownership in Chinese PLCs: Does Ownership Concentration Always Enhance Corporate Value?

    Directory of Open Access Journals (Sweden)

    Jin-Hui Luo

    2014-02-01

    Full Text Available In this paper we investigate the relationship between family ownership structure and corporate value across a sample of 1314 firm-year observations of China’s family publicly listed companies (PLCs, from 2004 to 2008. We find a significant inverse-U-shaped relationship between the controlling family’s ultimate cash-flow rights and corporate value; as measured by Tobin’s Q. That is, as family-ownership concentration increases, corporate value first increases and then decreases. This finding refreshes our understanding of the relationship between family-ownership concentration and corporate value in emerging economies such as found in China. We corroborate prior findings that when controlling families hold excess control over cash-flow rights, corporate value is significantly lowered, while multiple large shareholders structure is significantly associated with higher corporate value. In addition; board independence is found to significantly improve corporate value in the context of family-concentrated ownership. We also test for potential endogeneity between family ownership and corporate value and find our results to be robust.

  13. Radon concentrations in different types of dwellings in Israel

    International Nuclear Information System (INIS)

    Epstein, L.; Koch, J.; Riemer, T.; Haquin, G.; Orion, I.

    2014-01-01

    The average radon concentration in Israeli dwellings was assessed by combining the results of a 2006 radon survey in single family houses with the results of a 2011 radon survey in apartments of multi-storey buildings. Both surveys were based on long-term measurements using CR-39 detectors. The survey in multi-storey buildings was intended to assess the influence of recent practices in the local building industry on the radon concentrations. These practices include the use of building materials with higher concentrations of the natural radionuclides in the last 20 y than before, as well as the improvement in sealing techniques over that period. Another practice in place since the early 1990's is the building of a shielded area in every apartment that is known as an RSS (residential secure space). The RSS is a room built from massive concrete walls, floor and ceiling that can be hermetically sealed and is intended to protect its residents from a missile attack. The influence of the above-mentioned features on radon concentrations was estimated by dividing the participating apartments into two groups: apartments in buildings >20 y, built using building materials with low concentrations of the natural radionuclides, regular sealing and without an RSS and apartments in buildings newer than 10 y, built using building materials with higher concentrations of the natural radionuclides, improved sealing and including an RSS. It was found that the average radon concentration in apartments in new buildings was significantly higher than in old buildings and the average radon concentration in single-family houses was significantly higher than in apartments in multi-storey buildings. Doses due to indoor radon were estimated on the basis of the updated information included in the 2009 International Commission on Radiological Protection statement on radon. (authors)

  14. Dynamic thermal analysis of a concentrated photovoltaic system

    Science.gov (United States)

    Avrett, John T., II; Cain, Stephen C.; Pochet, Michael

    2012-02-01

    Concentrated photovoltaic (PV) technology represents a growing market in the field of terrestrial solar energy production. As the demand for renewable energy technologies increases, further importance is placed upon the modeling, design, and simulation of these systems. Given the U.S. Air Force cultural shift towards energy awareness and conservation, several concentrated PV systems have been installed on Air Force installations across the country. However, there has been a dearth of research within the Air Force devoted to understanding these systems in order to possibly improve the existing technologies. This research presents a new model for a simple concentrated PV system. This model accurately determines the steady state operating temperature as a function of the concentration factor for the optical part of the concentrated PV system, in order to calculate the optimum concentration that maximizes power output and efficiency. The dynamic thermal model derived is validated experimentally using a commercial polysilicon solar cell, and is shown to accurately predict the steady state temperature and ideal concentration factor.

  15. Concentrating Solar Power. Technology Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-10-15

    Concentrating solar power can contribute significantly to the world's energy supply. As shown in this roadmap, this decade is a critical window of opportunity during which CSP could become a competitive source of electrical power to meet peak and intermediate loads in the sunniest parts of the world. This roadmap identifies technology, economy and policy goals and milestones needed to support the development and deployment of CSP, as well as ongoing advanced research in CSF. It also sets out the need for governments to implement strong, balanced policies that favour rapid technological progress, cost reductions and expanded industrial manufacturing of CSP equipment to enable mass deployment. Importantly, this roadmap also establishes a foundation for greater international collaboration. The overall aim of this roadmap is to identify actions required - on the part of all stakeholders - to accelerate CSP deployment globally. Many countries, particularly in emerging regions, are only just beginning to develop CSP. Accordingly, milestone dates should be considered as indicative of urgency, rather than as absolutes. This roadmap is a work in progress. As global CSP efforts advance and an increasing number of CSP applications are developed, new data will provide the basis for updated analysis. The IEA will continue to track the evolution of CSP technology and its impacts on markets, the power sector and regulatory environments, and will update its analysis and set additional tasks and milestones as new learning comes to light.

  16. Urinary concentrating processes in vertebrates.

    Science.gov (United States)

    Schmidt-Nielsen, B.

    1979-01-01

    Avian and mammalian kidneys can produce a urine hyperosmotic to the blood by means of a renal countercurrent system. Birds are uricotelic; mammals are ureotelic. It is proposed that the inner medulla present in mammalian, but not in avian kidneys serves specifically to accumulate urea in the inner and outer medulla. Among mammalian kidneys the degree to which urea accumulates in the inner medulla is inversely related to the complexity of the vascular bundles (in the outer medulla) and the cortical urea recycling index. A model is proposed for urea recycling via the vascular bundles. The renal pelvis varies in size among mammals. Its relative size is unrelated to the type of vascular bundles, cortical recycling index; or urea accumulation in the inner medulla. Since urine refluxes into the renal pelvis during rising urine flow only, the function of the pelvis could be that of bringing the more dilute urine into contact with the outer medulla and underlying capillaries, thereby aiding in reducing the urea concentration in outer and inner medulla during rising urine flow. The size of the renal pelvis may be related to the volume of the inner medulla. Other factors may also be involved. Images FIG. 1 FIG. 3 FIG. 5 FIG. 6 FIG. 9 FIG. 10 FIG. 11 FIG. 12 FIG. 13 PMID:538955

  17. Summary of Dissolved Concentration Limits

    International Nuclear Information System (INIS)

    Yueting Chen

    2001-01-01

    According to the Technical Work Plan titled Technical Work Plan for Waste Form Degradation Process Model Report for SR (CRWMS M and O 2000a), the purpose of this study is to perform abstractions on solubility limits of radioactive elements based on the process-level information and thermodynamic databases provided by Natural Environment Program Operations (NEPO) and Waste Package Operations (WPO). The scope of this analysis is to produce solubility limits as functions, distributions, or constants for all transported radioactive elements identified by the Performance Assessment Operations (PAO) radioisotope screening. Results from an expert elicitation for solubility limits of most radioactive elements were used in the previous Total System Performance Assessments (TSPAs). However, the elicitation conducted in 1993 does not meet the criteria set forth by the U.S. Nuclear Regulatory Commission (NRC) due to lack of documentation and traceability (Kotra et al. 1996, Section 3). Therefore, at the Waste Form Abstraction Workshop held on February 2-4, 1999, at Albuquerque, New Mexico, the Yucca Mountain Site Characterization Project (YMP) decided to develop geochemical models to study solubility for the proposed Monitored Geologic Repository. WPO/NEPO is to develop process-level solubility models, including review and compilation of relevant thermodynamic data. PAO's responsibility is to perform abstractions based on the process models and chemical conditions and to produce solubility distributions or response surfaces applicable to the proposed repository. The results of this analysis and conceptual model will feed the performance assessment for Total System Performance Assessment--Site Recommendation (TSPA-SR) and Total System Performance Assessment--License Application (TSPA-LA), and to the Waste Form Degradation Process Model Report section on concentration limits

  18. Summary of Dissolved Concentration Limits

    Energy Technology Data Exchange (ETDEWEB)

    Yueting Chen

    2001-06-11

    According to the Technical Work Plan titled Technical Work Plan for Waste Form Degradation Process Model Report for SR (CRWMS M&O 2000a), the purpose of this study is to perform abstractions on solubility limits of radioactive elements based on the process-level information and thermodynamic databases provided by Natural Environment Program Operations (NEPO) and Waste Package Operations (WPO). The scope of this analysis is to produce solubility limits as functions, distributions, or constants for all transported radioactive elements identified by the Performance Assessment Operations (PAO) radioisotope screening. Results from an expert elicitation for solubility limits of most radioactive elements were used in the previous Total System Performance Assessments (TSPAs). However, the elicitation conducted in 1993 does not meet the criteria set forth by the U.S. Nuclear Regulatory Commission (NRC) due to lack of documentation and traceability (Kotra et al. 1996, Section 3). Therefore, at the Waste Form Abstraction Workshop held on February 2-4, 1999, at Albuquerque, New Mexico, the Yucca Mountain Site Characterization Project (YMP) decided to develop geochemical models to study solubility for the proposed Monitored Geologic Repository. WPO/NEPO is to develop process-level solubility models, including review and compilation of relevant thermodynamic data. PAO's responsibility is to perform abstractions based on the process models and chemical conditions and to produce solubility distributions or response surfaces applicable to the proposed repository. The results of this analysis and conceptual model will feed the performance assessment for Total System Performance Assessment--Site Recommendation (TSPA-SR) and Total System Performance Assessment--License Application (TSPA-LA), and to the Waste Form Degradation Process Model Report section on concentration limits.

  19. Recovery of uranium mineral concentrate from copper tailings

    International Nuclear Information System (INIS)

    Chakravarty, S.; Tewari, U.K.; Beri, K.K.

    1991-01-01

    Based on the studies conducted on the samples of copper tailings from Surda Copper Concentrator plant, wet concentrating table (Diaster Diagonal Deck) was found most suitable for recovering uranium mineral concentrate. Based on this technique, uranium recovery plants were set up at Surda, Rakha and Mosabani. The recoveries obtained from Surda Uranium Recovery Plant and Rakha Uranium Recovery Plant were in the range of 40-50%. But in Mosaboni Uranium Recovery Plant which is treating copper tailings from Mosaboni Copper Concentrator Plant, the biggest concentrator plant processing nearly 2,700 MT/day of copper ore, the recovery by wet concentrating tables was found to be around 22%. Low recovery was mainly due to low concentration of uranium in ore and as well as more percentage of uranium distribution in fines which tables were unable to recover. Studies were done to recover uranium mineral concentrate from the fines with new set of equipment viz. Curved Static Screen/Bartles Mozley Separator/Cross Belt Concentrator. This gave an improvement of 14-16% only. Studies by low acid leaching in chemical process side have shown that an overall recovery of 68% can be achieved. Though the chemical process is best as far as recovery is concerned but there are several constraints. The major constraint is pertaining to environmental and pollution control. Depending on the results of studies to overcome the constraints decision for the process to be adopted will be taken up and executed. The test results and plant performance data have also been included in the paper. (author). 8 figs., 11 tabs., 1 appendix

  20. Normal lactate concentration range in the neonatal brain.

    Science.gov (United States)

    Tomiyasu, Moyoko; Aida, Noriko; Shibasaki, Jun; Tachibana, Yasuhiko; Endo, Mamiko; Nozawa, Kumiko; Shimizu, Eiji; Tsuji, Hiroshi; Obata, Takayuki

    2016-11-01

    Lactate peaks are occasionally observed during in vivo magnetic resonance spectroscopy (MRS) scans of the neonatal brain, even in healthy patients. The purpose of this study was to investigate the normal range of neonatal brain lactate concentration, as a definitive normal range would be clinically valuable. Using a clinical 3T scanner (echo/repetition times, 30/5000ms), single-voxel MRS data were obtained from the basal ganglia (BG) and centrum semiovale (CS) in 48 healthy neonates (postconceptional age (PCA), 30-43weeks), nine infants (age, 1-12months old), and 20 children (age, 4-15years). Lactate concentrations were calculated using an MRS signal quantification program, LCModel. Correlations between regional lactate concentration and PCA (neonates), or age (all subjects) were investigated. Absolute lactate concentrations of the BG and CS were as follows: neonates, 0.77mM (0-2.02) [median (range)] and 0.77 (0-1.42), respectively; infants, 0.38 (0-0.79) and 0.49 (0.17-1.17); and children, 0.17 (0-0.76) and 0.22 (0-0.80). Overall, subjects' lactate concentrations decreased significantly with age (Spearman: BG, n=61, ρ=-0.38, p=0.003; CS, n=68, ρ=-0.57, p<0.001). However, during the neonatal period no correlations were detected between lactate concentration in either region and PCA. We determined normal ranges of neonatal lactate concentration, which may prove useful for diagnostic purposes. Further studies regarding changes in brain lactate concentration during development would help clarify the reasons for higher concentrations observed during the neonatal period, and contribute to improvements in diagnoses. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Temporal Variability of Microplastic Concentrations in Freshwater Streams

    Science.gov (United States)

    Watkins, L.; Walter, M. T.

    2016-12-01

    Plastic pollution, specifically the size fraction less than 5mm known as microplastics, is an emerging contaminant in waterways worldwide. The ability of microplastics to adsorb and transport contaminants and microbes, as well as be ingested by organisms, makes them a concern in both freshwater and marine ecosystems. Recent efforts to determine the extent of microplastic pollution are increasingly focused on freshwater systems, but most studies have reported concentrations at a single time-point; few have begun to uncover how plastic concentrations in riverine systems may change through time. We hypothesize the time of day and season of sampling influences the concentrations of microplastics in water samples and more specifically, that daytime stormflow samples contain the highest microplastic concentrations due to maximized runoff and wastewater discharge. In order to test this hypothesis, we sampled in two similar streams in Ithaca, New York using a 333µm mesh net deployed within the thalweg. Repeat samples were collected to identify diurnal patterns as well as monthly variation. Samples were processed in the laboratory following the NOAA wet peroxide oxidation protocol. This work improves our ability to interpret existing single-time-point survey results by providing information on how microplastic concentrations change over time and whether concentrations in existing stream studies are likely representative of their location. Additionally, these results will inform future studies by providing insight into representative sample timing and capturing temporal trends for the purposes of modeling and of developing regulations for microplastic pollution.

  2. Air ion concentrations in various urban outdoor environments

    Science.gov (United States)

    Ling, Xuan; Jayaratne, Rohan; Morawska, Lidia

    2010-06-01

    Atmospheric ions are produced by many natural and anthropogenic sources and their concentrations vary widely between different environments. There is very little information on their concentrations in different types of urban environments, how they compare across these environments and their dominant sources. In this study, we measured airborne concentrations of small ions, particles and net particle charge at 32 different outdoor sites in and around a major city in Australia and identified the main ion sources. Sites were classified into seven groups as follows: park, woodland, city centre, residential, freeway, power lines and power substation. Generally, parks were situated away from ion sources and represented the urban background value of about 270 ions cm -3. Median concentrations at all other groups were significantly higher than in the parks. We show that motor vehicles and power transmission systems are two major ion sources in urban areas. Power lines and substations constituted strong unipolar sources, while motor vehicle exhaust constituted strong bipolar sources. The small ion concentration in urban residential areas was about 960 cm -3. At sites where ion sources were co-located with particle sources, ion concentrations were inhibited due to the ion-particle attachment process. These results improved our understanding on air ion distribution and its interaction with particles in the urban outdoor environment.

  3. Installation package for concentrating solar collector panels

    Science.gov (United States)

    1978-01-01

    The concentrating solar collector panels comprise a complete package array consisting of collector panels using modified Fresnel prismatic lenses for a 10 to 1 concentrating ratio, supporting framework, fluid manifolding and tracking drive system, and unassembled components for field erection.

  4. Entropy concentration and the empirical coding game

    NARCIS (Netherlands)

    Grünwald, P.D.

    2008-01-01

    We give a characterization of maximum entropy/minimum relative entropy inference by providing two 'strong entropy concentration' theorems. These theorems unify and generalize Jaynes''concentration phenomenon' and Van Campenhout and Cover's 'conditional limit theorem'. The theorems characterize

  5. Nonimaging solar concentrator with uniform irradiance

    Science.gov (United States)

    Winston, Roland; O'Gallagher, Joseph J.; Gee, Randy C.

    2004-09-01

    We report results of a study our group has undertaken under NREL/DOE auspices to design a solar concentrator with uniform irradiance on a planar target. This attribute is especially important for photovoltaic concentrators.

  6. Relationship between bank ownership concentration on capital ...

    African Journals Online (AJOL)

    Relationship between bank ownership concentration on capital adequacy, liquidity, ... In this study we explore the effects of ownership concentration on the ... are material factors in explaining banks' behavior and their market performance.

  7. 2011 NATA - Risks and Annual Ambient Concentrations

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset includes the modeled annual ambient concentrations and risks at the census tract level for the 2011 National Air Toxics Assessment. All concentrations...

  8. Oxygen Concentration Inside a Functioning Photosynthetic Cell

    OpenAIRE

    Kihara, Shigeharu; Hartzler, Daniel A.; Savikhin, Sergei

    2014-01-01

    The excess oxygen concentration in the photosynthetic membranes of functioning oxygenic photosynthetic cells was estimated using classical diffusion theory combined with experimental data on oxygen production rates of cyanobacterial cells. The excess oxygen concentration within the plesiomorphic cyanobacterium Gloeobactor violaceus is only 0.025 μM, or four orders of magnitude lower than the oxygen concentration in air-saturated water. Such a low concentration suggests that the first oxygenic...

  9. Protein Concentrate Production from Thin Stillage.

    Science.gov (United States)

    Ratanapariyanuch, Kornsulee; Shim, Youn Young; Emami, Shahram; Reaney, Martin J T

    2016-12-21

    Two-stage fermentation (TSF) of saccharified wheat with a consortium of endemic lactobacilli produced CO 2 and induced colloid separation of fermented solution to produce a protein concentrate (PC). Protein-rich slurry (50%, db) was obtained by decanting solution or skimming floating material during or after TSF. Washing and drying processes were explored to improve protein content, extend storage life of slurry, and yield converted stillage for compound recovery. Centrifuging and washing slurry afforded a PC and clarified solution. PC protein content increased to 60% (w/w, db). The PC was dried in a spray dryer or drum dryer or tray dryer. Dried PC water activity ranged 0.23-0.30. The dried PC lysine content was low, but lysine availability (95%) was excellent. Liquid from TSF and washing was readily microfiltered. Mass recovery of protein, glycerol, 1,3-propanediol, lactic acid, acetic acid, and glycerylphosphorylcholine from combined TSF, washing, and filtration were 66, 76, 72, 77, 74, and 84%, respectively.

  10. Control device for combustible gas concentration

    International Nuclear Information System (INIS)

    Osawa, Yasuo.

    1988-01-01

    Purpose: To control the concentration of combustible gases such as hydrogen evolved in a reactor container upon loss-of-coolant accidents. Constitution: Combustible gases evolved from the lower area of a drywell in which a combustible atmosphere is liable to be formed locally are taken out through a take-out pipeway to the outside of a reactor container and processed by a hydrogen-oxygen recombiner. Combustible gases in other areas of the drywell are also introduced to the lower area of the drywell and then taken-out externally for procession. Further, combustible gases in the suppression chamber are introduced by the opening of a vacuum breaking valve through a gas supply pipe to the lower area of the drywell and fluids in the drywell are stirred and diluted with fluids exhausted from the gas supply pipe. Disposition of such take-out pipeway and gas supply pipe can reduce the possibility of forming local combustible atmosphere to improve the integrity of the reactor container. (Kamimura, M.)

  11. Dependence of spleen sequestration on erythrocytes following administration of various concentrations of BMHP-197Hg

    International Nuclear Information System (INIS)

    Kapff, S. v.

    1980-01-01

    In the course of routine splenic scintiscanning, the effects of BMHP-Hg 197 concentrations on the kinetics of damaged erythrocytes and on image quality have been investigated. The following findings were obtained: 1. Significant displacement of the Price-Jones curve in dependence of BMHP concentrations. 2. No significant enzymatic changes 3. An enhanced labelling index at high concentrations and a higher spleen sequestration rate 4. A significant improvement of scintiscan quality at higher concentrations 5. Erythrocyte washing before incubation with BMHP was unnecessary as it does not improve the results to an extent that would warrant the tedious procedure. (orig.) [de

  12. Relationship between silicon concentration and creatinine clearance

    International Nuclear Information System (INIS)

    Miura, Y.; Nakai, K.; Itoh, C.; Horikiri, J.; Sera, K.; Sato, M.

    1998-01-01

    Silicon levels in dialysis patients are markedly increasing. Using PIXE we determined the relationship between silicon concentration and creatinine clearance in 30 samples. Urine silicon concentration were significantly correlated to creatinine clearance (p<0.001). And also serum silicon concentration were significantly correlated to creatinine clearance (p<0.0001). (author)

  13. Color corrected Fresnel lens for solar concentration

    International Nuclear Information System (INIS)

    Kritchman, E.M.

    1979-01-01

    A new linear convex Fresnel lens with its groove side down is described. The design philosophy is similar to the highly concentrating two focal Fresnel lens but including a correction for chromatic aberration. A solar concentration ratio as high as 80 is achieved. For wide acceptance angles the concentration nears the theoretical maximum. (author)

  14. Effects of concentrated sunlight on organic photovoltaics

    DEFF Research Database (Denmark)

    Tromholt, Thomas; Katz, Eugene A.; Hirsch, Baruch

    2010-01-01

    We report the effects of concentrated sunlight on key photovoltaic parameters and stability of organic photovoltaics (OPV). Sunlight collected and concentrated outdoors was focused into an optical fiber and delivered onto a 1 cm2 bulk-heterojunction cell. Sunlight concentration C was varied gradu...

  15. Method of enriching oil shale concentrate

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, M

    1942-02-14

    The method is characterized by producing one concentrate first and then this concentrate, in water solution using suitable apparatus, is separated by settling into one heavier bottom portion, rich in mineral matter, and into a lighter slime containing concentrated organic substance.

  16. Concentration dependence of biotransformation in fish liver S9: Optimizing substrate concentrations to estimate hepatic clearance for bioaccumulation assessment.

    Science.gov (United States)

    Lo, Justin C; Allard, Gayatri N; Otton, S Victoria; Campbell, David A; Gobas, Frank A P C

    2015-12-01

    In vitro bioassays to estimate biotransformation rate constants of contaminants in fish are currently being investigated to improve bioaccumulation assessments of hydrophobic contaminants. The present study investigates the relationship between chemical substrate concentration and in vitro biotransformation rate of 4 environmental contaminants (9-methylanthracene, pyrene, chrysene, and benzo[a]pyrene) in rainbow trout (Oncorhynchus mykiss) liver S9 fractions and methods to determine maximum first-order biotransformation rate constants. Substrate depletion experiments using a series of initial substrate concentrations showed that in vitro biotransformation rates exhibit strong concentration dependence, consistent with a Michaelis-Menten kinetic model. The results indicate that depletion rate constants measured at initial substrate concentrations of 1 μM (a current convention) could underestimate the in vitro biotransformation potential and may cause bioconcentration factors to be overestimated if in vitro biotransformation rates are used to assess bioconcentration factors in fish. Depletion rate constants measured using thin-film sorbent dosing experiments were not statistically different from the maximum depletion rate constants derived using a series of solvent delivery-based depletion experiments for 3 of the 4 test chemicals. Multiple solvent delivery-based depletion experiments at a range of initial concentrations are recommended for determining the concentration dependence of in vitro biotransformation rates in fish liver fractions, whereas a single sorbent phase dosing experiment may be able to provide reasonable approximations of maximum depletion rates of very hydrophobic substances. © 2015 SETAC.

  17. Teleophthalmology: improving patient outcomes?

    Directory of Open Access Journals (Sweden)

    Sreelatha OK

    2016-02-01

    Full Text Available Omana Kesary Sreelatha,1 Sathyamangalam VenkataSubbu Ramesh2 1Ophthalmology Department, Sultan Qaboos University Hospital, Muscat, Oman; 2Department of Optometry, School of Allied Health Sciences, Manipal University, Manipal, India Abstract: Teleophthalmology is gaining importance as an effective eye care delivery modality worldwide. In many developing countries, teleophthalmology is being utilized to provide quality eye care to the underserved urban population and the unserved remote rural population. Over the years, technological innovations have led to improvement in evidence and teleophthalmology has evolved from a research tool to a clinical tool. The majority of the current teleophthalmology services concentrate on patient screening and appropriate referral to experts. Specialty care using teleophthalmology services for the pediatric group includes screening as well as providing timely care for retinopathy of prematurity (ROP. Among geriatric eye diseases, specialty teleophthalmology care is focused toward screening and referral for diabetic retinopathy (DR, glaucoma, age-related macular degeneration (ARMD, and other sight-threatening conditions. Comprehensive vision screening and refractive error services are generally covered as part of most of the teleophthalmology methods. Over the past decades, outcome assessment of health care system includes patients’ assessments on their health, care, and services they receive. Outcomes, by and large, remain the ultimate validators of the effectiveness and quality of medical care. Teleophthalmology produces the same desired clinical outcome as the traditional system. Remote portals allow specialists to provide care over a larger region, thereby improving health outcomes and increasing accessibility of specialty care to a larger population. A high satisfaction level and acceptance is reported in the majority of the studies because of increased accessibility and reduced traveling cost and time

  18. Reliability Evaluation of Concentric Butterfly Valve Using Statistical Hypothesis Test

    International Nuclear Information System (INIS)

    Chang, Mu Seong; Choi, Jong Sik; Choi, Byung Oh; Kim, Do Sik

    2015-01-01

    A butterfly valve is a type of flow-control device typically used to regulate a fluid flow. This paper presents an estimation of the shape parameter of the Weibull distribution, characteristic life, and B10 life for a concentric butterfly valve based on a statistical analysis of the reliability test data taken before and after the valve improvement. The difference in the shape and scale parameters between the existing and improved valves is reviewed using a statistical hypothesis test. The test results indicate that the shape parameter of the improved valve is similar to that of the existing valve, and that the scale parameter of the improved valve is found to have increased. These analysis results are particularly useful for a reliability qualification test and the determination of the service life cycles

  19. Reliability Evaluation of Concentric Butterfly Valve Using Statistical Hypothesis Test

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Mu Seong; Choi, Jong Sik; Choi, Byung Oh; Kim, Do Sik [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2015-12-15

    A butterfly valve is a type of flow-control device typically used to regulate a fluid flow. This paper presents an estimation of the shape parameter of the Weibull distribution, characteristic life, and B10 life for a concentric butterfly valve based on a statistical analysis of the reliability test data taken before and after the valve improvement. The difference in the shape and scale parameters between the existing and improved valves is reviewed using a statistical hypothesis test. The test results indicate that the shape parameter of the improved valve is similar to that of the existing valve, and that the scale parameter of the improved valve is found to have increased. These analysis results are particularly useful for a reliability qualification test and the determination of the service life cycles.

  20. KOH concentration effect on the cycle life of nickel-hydrogen cells

    Science.gov (United States)

    Lim, H. S.; Verzwyvelt, S. A.

    1985-01-01

    Effects of KOH concentration on the cycle life of a sintered-type nickel electrode were studied in a boiler plate nickel-hydrogen cell at 23 C using an accelerated 45-min cycle regime at 80 percent depth of discharge. The cycle life improved greatly as the KOH concentration decreased, although the initial capacity of the cell decreased slightly. The cycle life improved by a factor of two or more when the KOH concentration was reduced from 36 to 31 percent and by a similar factor from reductions of 31 to 26 percent. For many applications, this life improvement may outweigh the initial capacity decrease.

  1. Probiotic Yoghurts From Ultrafiltered Concentrated Milk

    Directory of Open Access Journals (Sweden)

    Kozludzhova Siyka

    2015-12-01

    Full Text Available In this paper, yoghurts from ultrafiltered concentrated whole milk with a volume reduction ratio 0, 2 and 3 with three different probiotic yoghurt starters were obtained. Their physiological, microbiological and rheological properties were examined. The concentrated probiotic yoghurts had high concentration of viable cells of the probiotic strain Lactobacillus delbrueckii ssp. bulgaricus (over 1010cfu/cm3. For the preparation of concentrated probiotic yoghurts the most appropriate volume reduction ratio was 2. The probiotic yoghurts with starters MZ2 and 1CM had the best structure. The concentrated probiotic yoghurts with all starters are functional foods.

  2. Photovoltaic applications of Compound Parabolic Concentrator (CPC)

    Science.gov (United States)

    Winston, R.

    1975-01-01

    The use of a compound parabolic concentrator as field collector, in conjunction with a primary focusing concentrator for photovoltaic applications is studied. The primary focusing concentrator can be a parabolic reflector, an array of Fresnel mirrors, a Fresnel lens or some other lens. Silicon solar cell grid structures are proposed that increase efficiency with concentration up to 10 suns. A ray tracing program has been developed to determine energy distribution at the exit of a compound parabolic concentrator. Projected total cost of a CPC/solar cell system will be between 4 and 5 times lower than for flat plate silicon cell arrays.

  3. Nonimaging concentrators for solar thermal energy

    Science.gov (United States)

    Winston, R.; Gallagher, J. J.

    1980-03-01

    A small experimental solar collector test facility was used to explore applications of nonimaging optics for solar thermal concentration in three substantially different configurations: a single stage system with moderate concentration on an evacuated absorber (a 5.25X evacuated tube Compound Parabolic Concentrator or CPC), a two stage system with high concentration and a non-evacuated absorber (a 16X Fresnel lens/CPC type mirror) and moderate concentration single stage systems with non-evacuated absorbers for lower temperature (a 3X and a 6.5X CPC). Prototypes of each of these systems were designed, built and tested. The performance characteristics are presented.

  4. Quantifying intracellular hydrogen peroxide perturbations in terms of concentration

    Directory of Open Access Journals (Sweden)

    Beijing K. Huang

    2014-01-01

    Full Text Available Molecular level, mechanistic understanding of the roles of reactive oxygen species (ROS in a variety of pathological conditions is hindered by the difficulties associated with determining the concentration of various ROS species. Here, we present an approach that converts fold-change in the signal from an intracellular sensor of hydrogen peroxide into changes in absolute concentration. The method uses extracellular additions of peroxide and an improved biochemical measurement of the gradient between extracellular and intracellular peroxide concentrations to calibrate the intracellular sensor. By measuring peroxiredoxin activity, we found that this gradient is 650-fold rather than the 7–10-fold that is widely cited. The resulting calibration is important for understanding the mass-action kinetics of complex networks of redox reactions, and it enables meaningful characterization and comparison of outputs from endogenous peroxide generating tools and therapeutics across studies.

  5. Cost effective manufacturing of the SEA 10X concentrator array

    Energy Technology Data Exchange (ETDEWEB)

    Kaminar, N.; McEntee, J.; Curchod, D. (Solar Engineering Applications Corp., San Jose, CA (United States))

    1991-11-01

    This report describes a low-cost, mass-producible 10X concentrator system that has been claimed to produce electricity at $0.04/kWh. It details changes in manufacturing techniques that could produce a concentrator system at a selling price of $0.71/W. (A simple design and a minimum number of parts and manufacturing steps reduced production costs.) Present production techniques, changes to improve these techniques, impediments to changes, and solutions to the impediments are described. This 10X concentrator system uses available components and manufacturing processes and one-sun solar cells in conjunction with inexpensive plastic lenses to generate about eight times the amount of electricity normally produced by these cells.

  6. Liver imaging with MDCT and high concentration contrast media

    International Nuclear Information System (INIS)

    Spielmann, Audrey L.

    2003-01-01

    Liver imaging has advanced greatly over the last 10 years with helical CT capability and more recently the addition of multidetector-row CT (MDCT). Multidetector CT technology facilitates imaging at faster speeds with improved image quality and less breathing artifact [Abdom. Imaging 25 (2000) 643]. Exquisite three-dimensional data sets can be obtained with thin collimation providing improved lesion detection, multiplanar imaging, and the ability to perform CT angiography of the liver and mesenteric vessels. New challenges arise with this advance in technology including safety considerations. The radiation dose to the patient has increased with MDCT and this is compounded by the ability to perform multi-phase liver imaging. Furthermore, issues of contrast media administration require reconsideration including optimal timing and rate of administration, the total volume of contrast needed and the ideal iodine concentration of the contrast media. Recently, the use of high concentration contrast media (HCCM) has been explored and study results to date will be reviewed

  7. MARKET CONCENTRATION IN TURKISH JOURNALISM SECTOR

    Directory of Open Access Journals (Sweden)

    ADEM KALÇA

    2013-05-01

    Full Text Available Concentration is a situation in which market structure of a sector is controlled by a few firms. At the present time, many analyzing methods such as Herfindahl-Hirschman and N-Firm Concentration Indexes are used to determine market structure.According to market concentration indexes, higher concentration level means more monopolistic market structure, lower concentration level means more full competitive market structure. In this study concentration levels of media groups in Turkish journalism sector within the scope of traditional journalism and internet journalism was analyzed via N-Firm Concentration and H-H Indexes. As a result of the study, it’s seen that first four biggest media groups have monopolistic competition in internet journalism sector,and oligopol structure in traditional journalism sector. According to H-H index analyze, there is monopolistic competition in the sector.

  8. New method of design of nonimaging concentrators.

    Science.gov (United States)

    Miñano, J C; González, J C

    1992-06-01

    A new method of designing nonimaging concentrators is presented and two new types of concentrators are developed. The first is an aspheric lens, and the second is a lens-mirror combination. A ray tracing of three-dimensional concentrators (with rotational symmetry) is also done, showing that the lens-mirror combination has a total transmission as high as that of the full compound parabolic concentrators, while their depth is much smaller than the classical parabolic mirror-nonimaging concentrator combinations. Another important feature of this concentrator is that the optically active surfaces are not in contact with the receiver, as occurs in other nonimaging concentrators in which the rim of the mirror coincides with the rim of the receiver.

  9. Fabrication and performance analysis of concentrated hybrid photovoltaic system

    Directory of Open Access Journals (Sweden)

    Murthy Krishna

    2018-01-01

    Full Text Available Sun is the most important source of renewable source of energy. During the past few decades there has been an ever-increasing interest in Photovoltaic (PV cells as it directly converts solar radiation into electricity. This paper involves the performance study of photovoltaic system under concentrated solar radiation. The main problem with the concentration solar energy is the drastic increase in temperature of the photovoltaic module resulting in a decrease in performance efficiency of the system. This problem of overheating of the system can be overcome by providing cooling which would ensure operation of the module in the optimal temperature range. Hence, the setup would function as a hybrid model serving the dual purpose of power generation while also utilizing the waste heat for water heating applications. The experimental set up consist of a novel arrangement of concentrator and reflector and the cooling system. The Hybrid Photovoltaic System was repeatedly tested under real time conditions on several days. A comparison was drawn between the results obtained from direct exposure of a standard photovoltaic module to that obtained from the hybrid system in order to better understand the improvement in performance parameters. The study shown a significant improvement of output of standard photovoltaic module under the concentrated solar radiation.

  10. Test results on parabolic dish concentrators for solar thermal power systems

    Science.gov (United States)

    Jaffe, Leonard D.

    1989-01-01

    This paper presents results of development testing of various solar thermal parabolic dish concentrators. The concentrators were mostly designed for the production of electric power using dish-mounted Rankine, Brayton or Stirling cycle engines, intended to be produced at low cost. Measured performance for various dishes included optical efficiencies ranging from 0.32 to 0.86 at a geometric concentration ratio of 500, and from about 0.09 to 0.85 at a geometric concentration ratio of 3000. Some malfunctions were observed. The tests should provide operating information of value in developing concentrators with improved performance and reduced maintenance.

  11. Estímulo no crescimento e na hidrólise de ATP em raízes de alface tratadas com humatos de vermicomposto: I - efeito da concentração Improving lettuce seedling root growth and ATP hydrolysis with humates from vermicompost: I - effect of vermicompost concentration

    Directory of Open Access Journals (Sweden)

    Maria Rita Cardoso Rodda

    2006-08-01

    Full Text Available O vermicomposto contém uma concentração elevada de substâncias húmicas e já é bem conhecido o efeito do seu uso sobre as propriedades do solo. No entanto, a ação direta das substâncias húmicas sobre o metabolismo das plantas é menos conhecida. O objetivo deste trabalho foi avaliar o uso de humatos extraídos de vermicomposto de esterco de curral com KOH 0,1 mol L-1 sobre o desenvolvimento e metabolismo de ATP em plântulas de alface. Após a germinação, plântulas de alface foram tratadas com os humatos em concentrações que variaram de 0 a 100 mg L-1 de C, durante quinze dias. Foram avaliados o crescimento da raiz e a atividade das bombas de H+ isoladas da fração microssomal do sistema radicular. Foi observado aumento na matéria fresca e seca do sistema radicular, bem como no número de sítios de mitose, raízes emergidas do eixo principal, na área e no comprimento radiculares, com o uso do humato na concentração de 25 mg L-1 de C. Também foi observado, nessa concentração, aumento significativo na hidrólise de ATP pelas bombas de H+, responsáveis pela geração de energia necessária à absorção de íons e pelo crescimento celular.Vermicomposts present a high content of humic substances and their effects on soil properties are well-documented. However, direct effects of humic substances on plant metabolism are less known. The aim of this work was to evaluate the use of humates isolated from cattle manure vermicompost with 0.1 mol L-1 KOH on root growth and ATP metabolism of lettuce seedlings. After germination, lettuce seedlings were treated with different humate concentrations (0 to 100 mg L-1 of C for 15 days. The root growth and the H+-ATPase activity of root cell microsomes isolated by differential centrifugation were evaluated. The humate treatment, at the concentration of 25 mg L-1 of C, increased fresh and dry root mass as well as root area and total length. Also there was a large increase in the number of

  12. Challenge for lowering concentration polarization in solid oxide fuel cells

    Science.gov (United States)

    Shimada, Hiroyuki; Suzuki, Toshio; Yamaguchi, Toshiaki; Sumi, Hirofumi; Hamamoto, Koichi; Fujishiro, Yoshinobu

    2016-01-01

    In the scope of electrochemical phenomena, concentration polarization at electrodes is theoretically inevitable, and lowering the concentration overpotential to improve the performance of electrochemical cells has been a continuing challenge. Electrodes with highly controlled microstructure, i.e., high porosity and uniform large pores are therefore essential to achieve high performance electrochemical cells. In this study, state-of-the-art technology for controlling the microstructure of electrodes has been developed for realizing high performance support electrodes of solid oxide fuel cells (SOFCs). The key is controlling the porosity and pore size distribution to improve gas diffusion, while maintaining the integrity of the electrolyte and the structural strength of actual sized electrode supports needed for the target application. Planar anode-supported SOFCs developed in this study realize 5 μm thick dense electrolyte (yttria-stabilized zirconia: YSZ) and the anode substrate (Ni-YSZ) of 53.6 vol.% porosity with a large median pore diameter of 0.911 μm. Electrochemical measurements reveal that the performance of the anode-supported SOFCs improves with increasing anode porosity. This Ni-YSZ anode minimizes the concentration polarization, resulting in a maximum power density of 3.09 W cm-2 at 800 °C using humidified hydrogen fuel without any electrode functional layers.

  13. Acute exercise improves motor memory

    DEFF Research Database (Denmark)

    Skriver, Kasper Christen; Roig, Marc; Lundbye-Jensen, Jesper

    2014-01-01

    We have recently shown that a single bout of acute cardiovascular exercise improves motor skill learning through an optimization of long-term motor memory. Here we expand this previous finding, to explore potential exercise-related biomarkers and their association with measures of motor memory...... practice whereas lactate correlated with better retention 1 hour as well as 24 hours and 7 days after practice. Thus, improvements in motor skill acquisition and retention induced by acute cardiovascular exercise are associated with increased concentrations of biomarkers involved in memory and learning...... processes. More mechanistic studies are required to elucidate the specific role of each biomarker in the formation of motor memory....

  14. A concentrated electrolyte for zinc hexacyanoferrate electrodes in aqueous rechargeable zinc-ion batteries

    Science.gov (United States)

    Kim, D.; Lee, C.; Jeong, S.

    2018-01-01

    In this study, a concentrated electrolyte was applied in an aqueous rechargeable zinc-ion battery system with a zinc hexacyanoferrate (ZnHCF) electrode to improve the electrochemical performance by changing the hydration number of the zinc ions. To optimize the active material, ZnHCF was synthesized using aqueous solutions of zinc nitrate with three different concentrations. The synthesized materials exhibited some differences in structure, crystallinity, and particle size, as observed by X-ray diffraction and scanning electron microscopy. Subsequently, these well-structured materials were applied in electrochemical tests. A more than two-fold improvement in the charge/discharge capacities was observed when the concentrated electrolyte was used instead of the dilute electrolyte. Additionally, the cycling performance observed in the concentrated electrolyte was superior to that in the dilute electrolyte. This improvement in the electrochemical performance may result from a decrease in the hydration number of the zinc ions in the concentrated electrolyte.

  15. Fundamental limits to position determination by concentration gradients.

    Directory of Open Access Journals (Sweden)

    Filipe Tostevin

    2007-04-01

    Full Text Available Position determination in biological systems is often achieved through protein concentration gradients. Measuring the local concentration of such a protein with a spatially varying distribution allows the measurement of position within the system. For these systems to work effectively, position determination must be robust to noise. Here, we calculate fundamental limits to the precision of position determination by concentration gradients due to unavoidable biochemical noise perturbing the gradients. We focus on gradient proteins with first-order reaction kinetics. Systems of this type have been experimentally characterised in both developmental and cell biology settings. For a single gradient we show that, through time-averaging, great precision potentially can be achieved even with very low protein copy numbers. As a second example, we investigate the ability of a system with oppositely directed gradients to find its centre. With this mechanism, positional precision close to the centre improves more slowly with increasing averaging time, and so longer averaging times or higher copy numbers are required for high precision. For both single and double gradients, we demonstrate the existence of optimal length scales for the gradients for which precision is maximized, as well as analyze how precision depends on the size of the concentration-measuring apparatus. These results provide fundamental constraints on the positional precision supplied by concentration gradients in various contexts, including both in developmental biology and also within a single cell.

  16. Plasma procalcitonin concentrations are increased in dogs with sepsis

    Science.gov (United States)

    Goggs, Robert; Milloway, Matthew; Troia, Roberta; Giunti, Massimo

    2018-01-01

    Sepsis, the life-threatening organ dysfunction caused by a dysregulated host response to infection, is difficult to identify and to prognosticate for. In people with sepsis, procalcitonin (PCT) measurement aids diagnosis, enables therapeutic monitoring and improves prognostic accuracy. This study used a commercial canine PCT assay to measure plasma PCT concentrations in dogs with gastric dilatation volvulus (GDV) syndrome and in dogs with sepsis. It was hypothesised that dogs with GDV syndrome and with sepsis have greater plasma PCT concentrations than healthy dogs and that dogs with sepsis have greater PCT concentrations than dogs with GDV syndrome. Before analysing canine plasma samples, the ability of the assay to identify canine PCT, in addition to assay imprecision and the lower limit of detection were established. The assay had low imprecision with coefficients of variation ≤4.5 per cent. The lower limit of detection was 3.4 pg/ml. Plasma PCT concentrations were measured in 20 dogs with sepsis, in 32 dogs with GDV syndrome and in 52 healthy dogs. Median (IQR) PCT concentration in dogs with sepsis 78.7 pg/ml (39.1–164.7) was significantly greater than in healthy dogs 49.8 pg/ml (36.2–63.7) (P=0.019), but there were no significant differences between PCT concentrations in dogs with GDV syndrome and controls (P=0.072) or between dogs with sepsis and GDV syndrome (P=1.000). Dogs with sepsis have significantly increased plasma PCT concentrations compared with healthy dogs, although considerable overlap between these populations was identified. Future investigations should confirm this finding in other populations and evaluate the diagnostic and prognostic value of PCT in dogs with sepsis. PMID:29682292

  17. Factors Affecting Tocopherol Concentrations in Soybean Seeds.

    Science.gov (United States)

    Carrera, Constanza S; Seguin, Philippe

    2016-12-21

    Soybean seeds contain several health-beneficial compounds, including tocopherols, which are used by the nutraceutical and functional food industries. Soybean tocopherol concentrations are, however, highly variable. Large differences observed in tocopherol concentrations among soybean genotypes together with the relatively simple biosynthetic pathway involving few genes support the feasibility of selecting for high-tocopherol soybean. Tocopherol concentrations are also highly influenced by environmental factors and field management. Temperature during seed filling and soil moisture appear to be the main factors affecting tocopherol concentrations; other factors such as soil fertility and solar radiation also affect concentrations and composition. Field management decisions including seeding date, row spacing, irrigation, and fertilization also affect tocopherols. Knowledge of factors affecting soybean tocopherols is essential to develop management strategies that will lead to the production of seeds with consistent target concentrations that will meet the needs of the nutraceutical and functional food industries.

  18. Causality Between Urban Concentration and Environmental Quality

    Directory of Open Access Journals (Sweden)

    Amin Pujiati

    2015-08-01

    Full Text Available Population is concentrated in urban areas can cause the external diseconomies on environment if it exceeds the carrying capacity of the space and the urban economy. Otherwise the quality of the environment is getting better, led to the concentration of population in urban areas are increasingly high. This study aims to analyze the relationship of causality between the urban concentration and environmental quality in urban agglomeration areas. The data used in the study of secondary data obtained from the Central Bureau of statistics and the City Government from 2000 to 2013. The analytical method used is the Granger causality and descriptive. Granger causality study results showed no pattern of reciprocal causality, between urban concentration and the quality of the environment, but there unidirectional relationship between the urban concentration and environmental quality. This means that increasing urban concentration led to decreased environmental quality.

  19. Improved radioanalytical methods

    International Nuclear Information System (INIS)

    Erickson, M.D.; Aldstadt, J.H.; Alvarado, J.S.; Crain, J.S.; Orlandini, K.A.; Smith, L.L.

    1995-01-01

    Methods for the chemical characterization of the environment are being developed under a multitask project for the Analytical Services Division (EM-263) within the US Department of Energy (DOE) Office of Environmental Management. This project focuses on improvement of radioanalytical methods with an emphasis on faster and cheaper routine methods. We have developed improved methods, for separation of environmental levels of technetium-99 and strontium-89/90, radium, and actinides from soil and water; and for separation of actinides from soil and water matrix interferences. Among the novel separation techniques being used are element- and class-specific resins and membranes. (The 3M Corporation is commercializing Empore trademark membranes under a cooperative research and development agreement [CRADA] initiated under this project). We have also developed methods for simultaneous detection of multiple isotopes using inductively coupled plasma-mass spectrometry (ICP-MS). The ICP-MS method requires less rigorous chemical separations than traditional radiochemical analyses because of its mass-selective mode of detection. Actinides and their progeny have been isolated and concentrated from a variety of natural water matrices by using automated batch separation incorporating selective resins prior to ICP-MS analyses. In addition, improvements in detection limits, sample volume, and time of analysis were obtained by using other sample introduction techniques, such as ultrasonic nebulization and electrothermal vaporization. Integration and automation of the separation methods with the ICP-MS methodology by using flow injection analysis is underway, with an objective of automating methods to achieve more reproducible results, reduce labor costs, cut analysis time, and minimize secondary waste generation through miniaturization of the process

  20. Point-of-care estimation of haemoglobin concentration in all age ...

    African Journals Online (AJOL)

    Point-of-care estimation of haemoglobin concentration in all age groups in clinical ... and the results were compared using standard scatter and difference plots. ... Hb measurements with a smaller sample volume, improved turnaround time, ...

  1. Target concentration intervention: beyond Y2K.

    Science.gov (United States)

    Holford, N H

    2001-01-01

    Target concentration intervention (TCI) is proposed as an alternative conceptual strategy to therapeutic drug monitoring (TDM). It is argued that the idea of a therapeutic range has limited the interpretation of measured drug concentrations and diminished the anticipated clinical benefit to patients by use of an oversimplified pharmacodynamic model. TCI on the other hand embraces pharmacokinetic and pharmacodynamic concepts and uses the idea of a target effect and associated target concentration to make rational individual dose decisions.

  2. Radon concentration in greehouses of Aomori Prefecture

    International Nuclear Information System (INIS)

    Iyogi, Takashi; Hisamatsu, Shun'ichi; Inaba, Jiro

    2001-01-01

    222 Rn causes a significant part of natural radiation dose to the general population. We previously surveyed 222 Rn concentrations in dwellings, and indoor and outdoor workplaces in Aomori Prefecture, and found geometric mean concentrations of 13, 22 and 4.4 Bq m -3 , respectively. The annual radiation dose rate of 4.3 mSv y -1 was estimated for people in the prefecture from these data. Since 222 Rn in the environment mainly originates from 226 Ra in the soil, that in cave is known to be higher than that in ordinary environments such as in buildings. Greenhouses are a possible place with high 222 Rn concentration, because of the soil exposed inside. However, the 222 Rn concentration in greenhouses has not yet been reported. We surveyed 222 Rn concentration in greenhouses of Aomori Prefecture. The 222 Rn concentration in 24 greenhouses at six locations in the prefecture were measured for approximately one year with passive Rn detectors using a polycarbonate film for counting α-rays, which could separate concentrations of 222 Rn from 220 Rn. Measurements of 222 Rn concentration and working level for one week carried out with active detectors to get equilibrium factors and the ratio of 222 Rn concentration in working time to non-working time in selected greenhouses. The geometric mean of 222 Rn concentrations in greenhouses was 13 Bq m -3 , and similar to that in dwellings. Significant seasonal variation was observed in 222 Rn concentrations. The geometric mean in June to September was 5.5 Bq m -3 , which was similar to that outside the greenhouses, while that in January to March was 19.5 Bq m -3 . These results showed that the 222 Rn concentration in greenhouses was comparable to that in dwellings. (author)

  3. Modeling sediment concentration of rill flow

    Science.gov (United States)

    Yang, Daming; Gao, Peiling; Zhao, Yadong; Zhang, Yuhang; Liu, Xiaoyuan; Zhang, Qingwen

    2018-06-01

    Accurate estimation of sediment concentration is essential to establish physically-based erosion models. The objectives of this study were to evaluate the effects of flow discharge (Q), slope gradient (S), flow velocity (V), shear stress (τ), stream power (ω) and unit stream power (U) on sediment concentration. Laboratory experiments were conducted using a 10 × 0.1 m rill flume under four flow discharges (2, 4, 8 and 16 L min-1), and five slope gradients (5°, 10°, 15°, 20° and 25°). The results showed that the measured sediment concentration varied from 87.08 to 620.80 kg m-3 with a mean value of 343.13 kg m-3. Sediment concentration increased as a power function with flow discharge and slope gradient, with R2 = 0.975 and NSE = 0.945. The sediment concentration was more sensitive to slope gradient than to flow discharge. The sediment concentration was well predicted by unit stream power (R2 = 0.937, NSE = 0.865), whereas less satisfactorily by flow velocity (R2 = 0.470, NSE = 0.539) and stream power (R2 = 0.773, NSE = 0.732). In addition, using the equations to simulate the measured sediment concentration of other studies, the result further indicated that slope gradient, flow discharge and unit stream power were good predictors of sediment concentration. In general, slope gradient, flow discharge and unit stream power seem to be the preferred predictors for estimating sediment concentration.

  4. Characterization and concentration of manganese ore waste

    International Nuclear Information System (INIS)

    Lima, Rosa Malena Fernandes; Pereira, Eder Esper; Reis, Erica Linhares; Silva, Glaucia Regina da

    2010-01-01

    In this work is presented the tests results of characterization and concentration by gravity and flotation methods carried out with a manganese sample waste. By optical microscopy, SEM/EDS and X-ray diffractometry were identified the Mn minerals spessartite (20%), tephroite (15%), rhodonite (5%), rhodochrosite and carbonates minerals (29%), opaque minerals and others (16%), micaceus minerals (6%) and quartz (4%). It was obtained Mn metallurgical recovery of 58% with Mn concentrate contents varying from 30 to 32.5%. The concentrates SiO_2 contents of flotation were until 1.5% smaller than those contents of gravity method concentrates. (author)

  5. Tritium concentrations in tree ring cellulose

    International Nuclear Information System (INIS)

    Kaji, Toshio; Momoshima, Noriyuki; Takashima, Yoshimasa.

    1989-01-01

    Measurements of tritium (tissue bound tritium; TBT) concentration in tree rings are presented and discussed. Such measurement is expected to provide a useful means of estimating the tritium level in the environment in the past. The concentration of tritium bound in the tissue (TBT) in a tree ring considered to reflect the environmental tritium level in the area at the time of the formation of the ring, while the concentration of tritium in the free water in the tissue represents the current environmental tritium level. First, tritium concentration in tree ring cellulose sampled from a cedar tree grown in a typical environment in Fukuoka Prefecture is compared with the tritium concentration in precipitation in Tokyo. Results show that the year-to-year variations in the tritium concentration in the tree rings agree well with those in precipitation. The maximum concentration, which occurred in 1963, is attibuted to atmospheric nuclear testing which was performed frequently during the 1961 - 1963 period. Measurement is also made of the tritium concentration in tree ring cellulose sampled from a pine tree grown near the Isotope Center of Kyushu University (Fukuoka). Results indicate that the background level is higher probably due to the release of tritium from the facilities around the pine tree. Thus, measurement of tritium in tree ring cellulose clearly shows the year-to-year variation in the tritium concentration in the atmosphere. (N.K.)

  6. Continuous measurements of outdoor radon concentrations

    International Nuclear Information System (INIS)

    Iida, T.; Ikebe, Y.; Suzuki, K.; Ueno, K.; Komura, K.; Kato, I.; Jin Yihe

    1993-01-01

    The authors studied and developed an electrostatic 222 Rn monitor and have measured continuously outdoor radon ( 222 Rn) concentrations at Nagoya University since 1985. Four 222 Rn monitors were newly constructed to measure outdoor 222 Rn concentrations at other locations. The 222 Rn concentrations at Nagoya and Kasugai show a clear diurnal variation in autumn, and a seasonal pattern of a spring-summer minimum and a autumn-winter maximum. The results at Toki are the same pattern as that at Nagoya except spring. The concentrations at Kanazawa show a slight seasonal variation. A clear diurnal variation is observed in summer. (4 figs.)

  7. Alignment method for parabolic trough solar concentrators

    Science.gov (United States)

    Diver, Richard B [Albuquerque, NM

    2010-02-23

    A Theoretical Overlay Photographic (TOP) alignment method uses the overlay of a theoretical projected image of a perfectly aligned concentrator on a photographic image of the concentrator to align the mirror facets of a parabolic trough solar concentrator. The alignment method is practical and straightforward, and inherently aligns the mirror facets to the receiver. When integrated with clinometer measurements for which gravity and mechanical drag effects have been accounted for and which are made in a manner and location consistent with the alignment method, all of the mirrors on a common drive can be aligned and optimized for any concentrator orientation.

  8. Interstitial adenosine concentration is increased by dipyridamole

    International Nuclear Information System (INIS)

    Gorman, M.W.; Wangler, R.D.; DeWitt, D.F.; Wang, C.Y.; Bassingthwaighte, J.B.; Sparks, H.V.

    1986-01-01

    The authors used the multiple indicator dilution technique to observe the capillary transport of adenosine (ADO) in isolated guinea pig hearts. Radiolabelled albumin, sucrose and ADO were injected on the arterial side and measured in venous samples collected during the following 20 seconds. Transport parameters calculated from these data include permeability-surface area products (PS) for transendothelial diffusion, endothelial cell (EC) uptake at the lumenal and ablumenal membranes, and EC metabolism. With simultaneous measurements of arterial and venous ADO concentrations and flow, the authors calculated the steady-state interstitial fluid (ISF) ADO concentration. Under control conditions the venous ADO concentration was 7.1 +/- 2.8 nM. The calculated ISF concentration depends on whether they assume the venous ADO comes from the ISF, or directly from ECs. These ISF concentrations are 25 +/- 12 nM and 9.8 +/- 4.0 nM, respectively. During dipyridamole infusion (10 uM) the EC transport parameters became nearly zero. Venous and ISF ADO concentrations increased to 33 +/- 8.9 nM and 169 +/- 42 nM, respectively. The authors conclude that the ISF ADO concentration is 1.5-4 fold higher than the venous concentration at rest, and the ISF concentration increases greatly with dipyridamole

  9. HYPOLIPEMIC THERAPY AND LOW SERUM CHOLESTEROL CONCENTRATION

    Directory of Open Access Journals (Sweden)

    Vladmila Bojanic

    2004-01-01

    Full Text Available Low concentration of plasma lipoproteins (hypolipoproteinemia presents decreasing concentrations of all or particular lipids components. Classification of hypolipoproteinemia (hypoLP divides them into: primary (hereditary and secondary. Primary hipoLP are rare diseases and their main characteristic is disorder of apolipoproteins synthesis, which leads to low serum cholesterol concentration. Secondary hipoLP are presented in many diseases. They have diagnostic, prognostic significance and present good therapeutic marker. However, modern therapeutic approaches for aggressive lipid lowering pointed out many questions about physiological limits for cholesterol lowering. These approaches, also, open many questions about consequences of low serum concentration of total cholesterol and triglicerides.

  10. Horizontally staggered lightguide solar concentrator with lateral displacement tracking for high concentration applications.

    Science.gov (United States)

    Ma, Hongcai; Wu, Lin

    2015-07-10

    We present the design of a horizontally staggered lightguide solar concentrator with lateral displacement tracking for high concentration applications. This solar concentrator consists of an array of telecentric primary concentrators, a horizontally staggered lightguide layer, and a vertically tapered lightguide layer. The primary concentrator is realized by two plano-aspheric lenses with lateral movement and maintains a high F-number over an angle range of ±23.5°. The results of the simulations show that the solar concentrator achieves a high concentration ratio of 500× with ±0.5° of acceptance angle by a single-axis tracker and dual lateral translation stages.

  11. THERMOCHEMICAL HEAT STORAGE FOR CONCENTRATED SOLAR POWER

    Energy Technology Data Exchange (ETDEWEB)

    PROJECT STAFF

    2011-10-31

    Thermal energy storage (TES) is an integral part of a concentrated solar power (CSP) system. It enables plant operators to generate electricity beyond on sun hours and supply power to the grid to meet peak demand. Current CSP sensible heat storage systems employ molten salts as both the heat transfer fluid and the heat storage media. These systems have an upper operating temperature limit of around 400 C. Future TES systems are expected to operate at temperatures between 600 C to 1000 C for higher thermal efficiencies which should result in lower electricity cost. To meet future operating temperature and electricity cost requirements, a TES concept utilizing thermochemical cycles (TCs) based on multivalent solid oxides was proposed. The system employs a pair of reduction and oxidation (REDOX) reactions to store and release heat. In the storage step, hot air from the solar receiver is used to reduce the oxidation state of an oxide cation, e.g. Fe3+ to Fe2+. Heat energy is thus stored as chemical bonds and the oxide is charged. To discharge the stored energy, the reduced oxide is re-oxidized in air and heat is released. Air is used as both the heat transfer fluid and reactant and no storage of fluid is needed. This project investigated the engineering and economic feasibility of this proposed TES concept. The DOE storage cost and LCOE targets are $15/kWh and $0.09/kWh respectively. Sixteen pure oxide cycles were identified through thermodynamic calculations and literature information. Data showed the kinetics of re-oxidation of the various oxides to be a key barrier to implementing the proposed concept. A down selection was carried out based on operating temperature, materials costs and preliminary laboratory measurements. Cobalt oxide, manganese oxide and barium oxide were selected for developmental studies to improve their REDOX reaction kinetics. A novel approach utilizing mixed oxides to improve the REDOX kinetics of the selected oxides was proposed. It partially

  12. Plasma carotenoid concentrations in relation to acute respiratory infections in elderly people

    NARCIS (Netherlands)

    Graat, J.M.; Kok, F.J.; Schouten, E.G.

    2004-01-01

    A high plasma carotenoid concentration could improve the immune response and result in decreased risk of infectious diseases. However, data on the relationship of plasma carotenoid concentration with acute respiratory infections, which occur frequently in elderly people, are scarce. We investigated,

  13. Mercury concentrations in lentic fish populations related to ecosystem and watershed characteristics

    Science.gov (United States)

    Andrew L. Rypel

    2010-01-01

    Predicting mercury (Hg) concentrations of fishes at large spatial scales is a fundamental environmental challenge with the potential to improve human health. In this study, mercury concentrations were examined for five species across 161 lakes and ecosystem, and watershed parameters were investigated as explanatory variables in statistical models. For all species, Hg...

  14. 光伏聚光器的改进与建筑照明造价成本节约的关系建模%Relation Modeling between the Improvement of Photovoltaic Concentrator and the Cost Saving of Architectural Lighting Cost

    Institute of Scientific and Technical Information of China (English)

    闫妍

    2015-01-01

    在建筑照明的光伏应用中,聚光器是建筑照明光伏产业的核心,它决定着整个光伏能源在建筑照明工程中应用的造价。在对光伏能源产业施工过程中,合理利用光照强度、单位面积太阳能电池的成本及转换效率,决定着光伏能源的发电成本造价。本文通过在光伏能源施工过程中,改进CPC聚光器接收角,扩大接收范围内的入射光,接收直射太阳光和部分散射太阳光,在聚光器底部放置封装光伏电池真空管,接收太阳周围辐射,大幅度降低了应用造价。实验证明,改进型聚光器能够提高光伏产业的发电能力,降低造价成本,在光伏能源产业施工建设过程中有较大的推广价值。%In the photovoltaic applications of architectural lighting, condenser is the core of the photovoltaic industry in ar⁃chitectural lighting, it determines the cost of the whole photovoltaic energy’s application in the architectural lighting engi⁃neering. In the construction process of photovoltaic energy, the cost of photovoltaic energy's power generation is decided by the rational utilization of illumination intensity, solar cell's cost per unit area and its conversion efficiency. Just as the article proposes, in the construction process of photovoltaic energy, first improve CPC condenser's acceptance angle so as to expand the incident light within the scope of receiving, with that it can receive direct sunlight and part of the scattering sunlight, then place a vacuum tube encapsulating the photovoltaic cell at the bottom of the condenser, in order to receive the radiations from around the sun, which will greatly reduce the cost of the application. Experiments show that the modi⁃fied condenser is able to enhance the power generation capacity of photovoltaic industry and meanwhile reduce its capital cost, thus having great popularization value in the construction process of photovoltaic energy industry.

  15. Flow-covariate prediction of stream pesticide concentrations.

    Science.gov (United States)

    Mosquin, Paul L; Aldworth, Jeremy; Chen, Wenlin

    2018-01-01

    Potential peak functions (e.g., maximum rolling averages over a given duration) of annual pesticide concentrations in the aquatic environment are important exposure parameters (or target quantities) for ecological risk assessments. These target quantities require accurate concentration estimates on nonsampled days in a monitoring program. We examined stream flow as a covariate via universal kriging to improve predictions of maximum m-day (m = 1, 7, 14, 30, 60) rolling averages and the 95th percentiles of atrazine concentration in streams where data were collected every 7 or 14 d. The universal kriging predictions were evaluated against the target quantities calculated directly from the daily (or near daily) measured atrazine concentration at 32 sites (89 site-yr) as part of the Atrazine Ecological Monitoring Program in the US corn belt region (2008-2013) and 4 sites (62 site-yr) in Ohio by the National Center for Water Quality Research (1993-2008). Because stream flow data are strongly skewed to the right, 3 transformations of the flow covariate were considered: log transformation, short-term flow anomaly, and normalized Box-Cox transformation. The normalized Box-Cox transformation resulted in predictions of the target quantities that were comparable to those obtained from log-linear interpolation (i.e., linear interpolation on the log scale) for 7-d sampling. However, the predictions appeared to be negatively affected by variability in regression coefficient estimates across different sample realizations of the concentration time series. Therefore, revised models incorporating seasonal covariates and partially or fully constrained regression parameters were investigated, and they were found to provide much improved predictions in comparison with those from log-linear interpolation for all rolling average measures. Environ Toxicol Chem 2018;37:260-273. © 2017 SETAC. © 2017 SETAC.

  16. Measurements of natural 41Ca concentrations

    International Nuclear Information System (INIS)

    Steinhof, A.

    1989-05-01

    Atomic mass spectroscopic examinations on 41 Ca were carried out in the UNILAC accelerator. A sensitivity of about 10 -15 was achieved. This would allow the measurement of present natural 41 Ca concentrations as soon as the problem of the transmission determination is solved. In this respect suggestions were worked out and their feasibility discussed. The detection of 41 Ca-ions is especially free of background when high UNILAC-energies are applied. An estimation showed a background level corresponding with a 41 Ca concentration of less then 10 -17 referred to 40 Ca. Besides an independent concept for the electromagnetic concentration of 41 Ca with variable concentration factors was developed. After being concentrated up to 50 respectively 25 times the initial concentration in the GSI mass separator, the 41 Ca concentration of three recent deer bones found in the Odenwald was measured by atomic mass spectroscopy in the 14UD-Pelletron Tandem in Rehovot (Israel). The measured 41 Ca concentrations ranged between 10 -14 to 10 -13 with consideration of the concentration factor. A theoretical study of the 41 Ca production in the earth's surface based on cosmic radiation illustrates the influence of trace elements on the neutron flux and thus on the 41 Ca production. This influence might be a possible explanation for the observed amplitude of variation of the 41 Ca concentration in recent bones which are of decisive importance for the feasibility of 41 Ca-related dating. In this work a method is suggested that does not depend on the amplitude of variation mentioned above and which would allow the determination of the erosion rate of rocks by its 41 Ca concentrations. (orig./HP) [de

  17. 21 CFR 155.191 - Tomato concentrates.

    Science.gov (United States)

    2010-04-01

    ... Tomato concentrates. (a) Identity—(1) Definition. Tomato concentrates are the class of foods each of... greater in length. (c) Blemishes, such as dark brown or black particles (specks)—not more than four exceed...; place a U.S. No. 12 screen (1.68 millimeters (0.066 inch) openings) over the sink drain; transfer the...

  18. Influence of surfactant concentration on nanohydroxyapatite growth

    Indian Academy of Sciences (India)

    Nanohydroxyapatite particles with different morphologies were synthesized through a microwave coupled hydrothermal method using CTAB as a template. A successful synthesis of nanosized HAP spheres, rods and fibres is achieved through this method by controlling the concentration of the surfactant. The concentration ...

  19. Stress Concentration around Holes in Anistropic Sheets

    DEFF Research Database (Denmark)

    Krenk, Steen

    1979-01-01

    The formulation of stress concentration problems of plane anisotropic elasticity in terms of integral equations is discussed. First the singular solutions of a concentrated force and a dislocation are formulated so that they remain valid in the case of double roots. The distribution of singularit...

  20. Luminescent Solar Concentrators with Fibre Geometry

    NARCIS (Netherlands)

    Edelenbosch, O.Y.; Fisher, M.; Patrignani, L.; Sark, W.G.J.H.M. van; Chatten, A.J.

    2013-01-01

    The potential of a fibre luminescent solar concentrator has been explored by means of both analytical and ray-tracing techniques. Coated fibres have been found to be more efficient than homogeneously doped fibres, at low absorption. For practical fibres concentration is predicted to be linear

  1. MCB-2 concentration meter for boric acid

    International Nuclear Information System (INIS)

    Lisecki, W.

    1978-01-01

    The principles are explained of the thermal neutron absorption method for monitoring boric acid concentration in the WWER type reactor coolant. The design principles and the characteristics of four variants are described of the MSB-2 type boric acid concentration monitor developed by IBJ. (B.S.)

  2. Postmortem Femoral Blood Concentrations of Risperidone

    DEFF Research Database (Denmark)

    Linnet, Kristian; Johansen, Sys Stybe

    2014-01-01

    Postmortem femoral blood concentrations of the antipsychotic drug risperidone and the active metabolite 9-hydroxyrisperidone were determined by an achiral LC-MS/MS method in 38 cases. The cause of death was classified as unrelated to risperidone in 30 cases, in which the sum of the concentration ...

  3. Universal distortion-free entanglement concentration

    International Nuclear Information System (INIS)

    Matsumoto, Keiji; Hayashi, Masahito

    2007-01-01

    We propose a new protocol of universal entanglement concentration, which converts many copies of an unknown pure state to an exact maximally entangled state. The yield of the protocol, which is outputted as a classical information, is probabilistic, and achieves the entropy rate with high probability, just as nonuniversal entanglement concentration protocols do

  4. Cream concentrated latex for foam rubber products

    Science.gov (United States)

    Suksup, R.; Imkaew, C.; Smitthipong, W.

    2017-12-01

    Fresh natural latex (around 40% rubber and 60% water) can be transformed to concentrated natural latex (around 60% rubber and 40% water) in order to realise economical transportation and easier latex product’s preparation. The concentrated natural latex is an extremely valuable material. It can be applied for many types of products, for example, foam rubber as pillow and mattress, elastic band, etc. Industrially, the concentrated natural latex can be prepared by centrifugation which requires an enormous expensive machine. From the eco-friendly products point of view, most of rubber entrepreneurs in the world try to develop a green rubber product. So, the main objective of this study is to prepare the cream concentrated latex without any sophisticated machine. Thus, we work on a simple, cheap and green method that does not use any expensive machine but uses water-based chemical as sodium alginate to prepare the cream concentrated latex. The optimal amount of sodium alginate in the latex was studied. The main characteristics of the cream concentrated latex were tested by various technics, such as alkalinity, total solid content (TSC), dry rubber content (DRC), etc. We found that there are no significant differences of results between fresh natural latex and cream concentrated latex, except for the TSC and DRC. The TSC and DRC of cream latex are higher than those of fresh natural latex. Finally, we propose a model of natural rubber particle and sodium alginate to form the cream concentrated latex.

  5. Filterability and Sludge Concentration in Membrane Bioreactors

    NARCIS (Netherlands)

    Lousada-Ferreira, M.

    2011-01-01

    The Thesis entitled “Filterability and Sludge Concentration in Membrane Bioreactors” aims at explaining the relation between Mixed Liquid Suspended Solids (MLSS) concentration, the amount of solids in the wastewater being treated, also designated as sludge, and filterability, being the ability of

  6. Uranium concentrations in fossils measured by SIMS

    International Nuclear Information System (INIS)

    Uyeda, Chiaki; Okano, Jun

    1988-01-01

    Semiquantitative analyses of uranium in fossil bones and teeth were carried out by SIMS. The results show a tendency that uranium concentrations in the fossils increase with the ages of the fossils. It is noticed that fossil bones and teeth having uranium concentration of more than several hundred ppm are not rare. (author)

  7. Technological Development of Brewing in Domestic Refrigerator Using Freeze-Dried Raw Materials

    Directory of Open Access Journals (Sweden)

    Angelika-Ioanna Gialleli

    2017-01-01

    Full Text Available Development of a novel directly marketable beer brewed at low temperature in a domestic refrigerator combined with yeast immobilization technology is presented in this study. Separately, freeze-dried wort and immobilized cells of the cryotolerant yeast strain Saccharomyces cerevisiae AXAZ-1 on tubular cellulose were used in low-temperature fermentation (2, 5 and 7 °C. The positive eff ect of tubular cellulose during low-temperature brewing was examined, revealing that freeze-dried immobilized yeast cells on tubular cellulose signifi cantly reduced the fermentation rates in contrast to freeze-dried free cells, although they are recommended for home-made beer production. Immobilization also enhanced the yeast resistance at low-temperature fermentation, reducing the minimum brewing temperature value from 5 to 2 °C. In the case of high-quality beer production, the eff ect of temperature and initial sugar concentration on the fermentation kinetics were assessed. Sensory enrichment of the produced beer was confi rmed by the analysis of the fi nal products, revealing a low diacetyl concentration, together with improved polyphenol content, aroma profi le and clarity. The proposed process for beer production in a domestic refrigerator can easily be commercialized and applied by dissolving the content of two separate packages in tap water; one package containing dried wort and the other dried immobilized cells on tubular cellulose suspended in tap water.

  8. Technological Development of Brewing in Domestic Refrigerator Using Freeze-Dried Raw Materials.

    Science.gov (United States)

    Gialleli, Angelika-Ioanna; Ganatsios, Vassilios; Terpou, Antonia; Kanellaki, Maria; Bekatorou, Argyro; Koutinas, Athanasios A; Dimitrellou, Dimitra

    2017-09-01

    Development of a novel directly marketable beer brewed at low temperature in a domestic refrigerator combined with yeast immobilization technology is presented in this study. Separately, freeze-dried wort and immobilized cells of the cryotolerant yeast strain Saccharomyces cerevisiae AXAZ-1 on tubular cellulose were used in low-temperature fermentation (2, 5 and 7 °C). The positive effect of tubular cellulose during low-temperature brewing was examined, revealing that freeze-dried immobilized yeast cells on tubular cellulose significantly reduced the fermentation rates in contrast to freeze-dried free cells, although they are recommended for home-made beer production. Immobilization also enhanced the yeast resistance at low-temperature fermentation, reducing the minimum brewing temperature value from 5 to 2 °C. In the case of high-quality beer production, the effect of temperature and initial sugar concentration on the fermentation kinetics were assessed. Sensory enrichment of the produced beer was confirmed by the analysis of the final products, revealing a low diacetyl concentration, together with improved polyphenol content, aroma profile and clarity. The proposed process for beer production in a domestic refrigerator can easily be commercialized and applied by dissolving the content of two separate packages in tap water; one package containing dried wort and the other dried immobilized cells on tubular cellulose suspended in tap water.

  9. Atmospheric relative concentrations in building wakes

    International Nuclear Information System (INIS)

    Ramsdell, J.V. Jr.; Simonen, C.A.; Smyth, S.B.

    1995-05-01

    This report documents the ARCON95 computer code developed for the U.S. Nuclear Regulatory Commission Office of Nuclear Regulatory Research for use in control room habitability assessments. The document includes a user's guide to the code, a description of the technical basis for the code, and a programmer's guide to the code. The ARCON95 code uses hourly meteorological data and recently developed methods for estimating dispersion in the vicinity of buildings to calculate relative concentrations at control room air intakes that would be exceeded no more five percent of the time. These concentrations are calculated for averaging periods ranging from one hour to 30 days in duration. Relative concentrations calculated by ARCON95 are significantly lower than concentrations calculated using the currently accepted procedure when winds are less than two meters per second. For higher wind speeds, ARCON95 calculates about the same concentrations as the current procedure

  10. Effect of paracentesis on ocular cloxacillin concentration

    International Nuclear Information System (INIS)

    Salminen, L.

    1978-01-01

    The effect of interior chamber puncture on cloxacillin concentration in the rabbit eye after intravenous injection was studied using a radioactive tracer method. The enhancement in drug concentration caused by paracentesis was most immediate and significant in the iris-ciliary body preparation. It was soon followed by high cloxacillin concentration in the aqueous humour, which contributed to elevated cloxacillin levels in the cornea, lens and anterior vitreous body, when compared to normal material. Contrary to normal eyes, cloxacillin concentration in the cornea of the punctured eyes was higher than in the limbal area. The morphological changes occurring after paracentesis are discussed. The breakdown of the hydrodynamic equilibrium in the eye, suggested as the only change after paracentesis by Raviola (1974), cannot merely explain the cloxacillin concentration changes measured in the punctured eye. (author)

  11. Obtain of uranium concentrates from fertil liquids

    International Nuclear Information System (INIS)

    Narvaez Castillo, W.A.

    1992-01-01

    This research tried to encounter the form to remove uranium from the rock in the best way, for that it was used different process like leaching, extraction, concentration and precipitation. To leach the mineral was chosen basic leaching, using a mixture of carbonate-sodium bicarbonate, this method is more adequated for the basic nature of the mineral. In extraction was used specific uranium ionic interchanges, so was chosen a tertiary amine like Alamina 336. The concentration phase is intimately binding with the extraction by ionic interchange, for the capability of resine's extraction to obtain concentrated liquids. When the liquids were obtained with high concentration of uranium in the same time were purified and then were precipitated, for that we employed a precipitant agent like: Sodium hydroxide, Amonium hydroxide, Magnesium hydroxide, Hydrogen peroxide and phosphates. With all concentrates we obtain the YELLOW CAKE

  12. Method development for the enantiomeric purity determination of low concentrations of adrenaline in local anaesthetic solutions by capillary electrophoresis

    NARCIS (Netherlands)

    Sänger-Van De Griend, Cari E.; Ek, Anders G.; Widahl-Näsman, Monica E.; Andersson, E. K Margareta

    2006-01-01

    L-Adrenaline is often included in local anaesthetic (LA) solutions for injection to improve the quality of the anaesthetic block. The concentration of the LA is between 2.5 and 20 mg/ml and the concentration of adrenaline is typically ≤0.1% of the LA concentration. In order to follow the

  13. Achieving target voriconazole concentrations more accurately in children and adolescents.

    Science.gov (United States)

    Neely, Michael; Margol, Ashley; Fu, Xiaowei; van Guilder, Michael; Bayard, David; Schumitzky, Alan; Orbach, Regina; Liu, Siyu; Louie, Stan; Hope, William

    2015-01-01

    Despite the documented benefit of voriconazole therapeutic drug monitoring, nonlinear pharmacokinetics make the timing of steady-state trough sampling and appropriate dose adjustments unpredictable by conventional methods. We developed a nonparametric population model with data from 141 previously richly sampled children and adults. We then used it in our multiple-model Bayesian adaptive control algorithm to predict measured concentrations and doses in a separate cohort of 33 pediatric patients aged 8 months to 17 years who were receiving voriconazole and enrolled in a pharmacokinetic study. Using all available samples to estimate the individual Bayesian posterior parameter values, the median percent prediction bias relative to a measured target trough concentration in the patients was 1.1% (interquartile range, -17.1 to 10%). Compared to the actual dose that resulted in the target concentration, the percent bias of the predicted dose was -0.7% (interquartile range, -7 to 20%). Using only trough concentrations to generate the Bayesian posterior parameter values, the target bias was 6.4% (interquartile range, -1.4 to 14.7%; P = 0.16 versus the full posterior parameter value) and the dose bias was -6.7% (interquartile range, -18.7 to 2.4%; P = 0.15). Use of a sample collected at an optimal time of 4 h after a dose, in addition to the trough concentration, resulted in a nonsignificantly improved target bias of 3.8% (interquartile range, -13.1 to 18%; P = 0.32) and a dose bias of -3.5% (interquartile range, -18 to 14%; P = 0.33). With the nonparametric population model and trough concentrations, our control algorithm can accurately manage voriconazole therapy in children independently of steady-state conditions, and it is generalizable to any drug with a nonparametric pharmacokinetic model. (This study has been registered at ClinicalTrials.gov under registration no. NCT01976078.). Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  14. Exploring the potential of Saccharomyces eubayanus as a parent for new interspecies hybrid strains in winemaking.

    Science.gov (United States)

    Magalhães, Frederico; Krogerus, Kristoffer; Castillo, Sandra; Ortiz-Julien, Anne; Dequin, Sylvie; Gibson, Brian

    2017-08-01

    Yeast cryotolerance brings some advantages for wine fermentations, including the improved aromatic complexity of white wines. Naturally cold-tolerant strains are generally less adept at wine fermentation but fermentative fitness can potentially be improved through hybridization. Here we studied the potential of using hybrids involving Saccharomyces eubayanus and a S. cerevisiae wine strain for low-temperature winemaking. Through screening the performance in response to variable concentrations of sugar, nitrogen and temperature, we isolated one hybrid strain that exhibited the superior performance. This hybrid strain was propagated and dried in pilot scale and tested for the fermentation of Macabeu and Sauvignon blanc grape musts. We obtained highly viable active dry yeast, which was able to efficiently ferment the grape musts with superior production of aroma active volatiles, in particular, 2-phenylethanol. The genome sequences of the hybrid strains revealed variable chromosome inheritance among hybrids, particularly within the S. cerevisiae subgenome. With the present paper, we expand the knowledge on the potentialities of using S. eubayanus hybrids in industrial fermentation at beverages other than lager beer. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. The concentrations of uranium in marine organisms

    Energy Technology Data Exchange (ETDEWEB)

    Matsuba, Mitsue; Ishii, Toshiaki; Nakahara, Motokazu; Nakamura, Ryoichi; Watabe, Teruhisa; Hirano, Shigeki [National Inst. of Radiological Sciences, Hitachinaka, Ibaraki (Japan). Laboratory for Radioecology

    2000-07-01

    Determination of uranium in sixty-one species of marine organisms was carried out by inductively coupled plasma mass spectrometry to obtain concentration factors and to estimate the internal radiation dose. The concentrations of uranium in soft tissues of marine animals were ranged from 0.077 to 5040 ng/g wet wt. Especially, the branchial heart of cephalopod molluscs showed the specific accumulation of uranium. The concentration factor of the branchial heart of Octopus vulgaris, which indicated the highest value, was calculated to be about 1.6 x 10{sup 3}, comparing with that (3.1 ng/ml) in coastal seawaters of Japan. The concentrations of uranium in hard tissues of marine invertebrates such as clam and sea urchin were similar to those in soft tissues. In contrast, hard tissues like bone, scale, fin, etc. of fishes showed much higher concentrations of uranium than soft tissues like muscle. The concentrations of uranium of twenty-two species of algae were ranged from 2 to 310 ng/g wet wt. Particularly, the brown alga Undaria pinnatifida showed the highest value of the uranium content in the algae and its concentration factor was calculated to be 10{sup 2}. (author)

  16. The concentrations of uranium in marine organisms

    International Nuclear Information System (INIS)

    Matsuba, Mitsue; Ishii, Toshiaki; Nakahara, Motokazu; Nakamura, Ryoichi; Watabe, Teruhisa; Hirano, Shigeki

    2000-01-01

    Determination of uranium in sixty-one species of marine organisms was carried out by inductively coupled plasma mass spectrometry to obtain concentration factors and to estimate the internal radiation dose. The concentrations of uranium in soft tissues of marine animals were ranged from 0.077 to 5040 ng/g wet wt. Especially, the branchial heart of cephalopod molluscs showed the specific accumulation of uranium. The concentration factor of the branchial heart of Octopus vulgaris, which indicated the highest value, was calculated to be about 1.6 x 10 3 , comparing with that (3.1 ng/ml) in coastal seawaters of Japan. The concentrations of uranium in hard tissues of marine invertebrates such as clam and sea urchin were similar to those in soft tissues. In contrast, hard tissues like bone, scale, fin, etc. of fishes showed much higher concentrations of uranium than soft tissues like muscle. The concentrations of uranium of twenty-two species of algae were ranged from 2 to 310 ng/g wet wt. Particularly, the brown alga Undaria pinnatifida showed the highest value of the uranium content in the algae and its concentration factor was calculated to be 10 2 . (author)

  17. Intrapulmonary concentration of enrofloxacin in healthy calves

    Science.gov (United States)

    OTOMARU, Konosuke; HIRATA, Masaya; IKEDO, Tomonobu; HORINOUCHI, Chie; NOGUCHI, Michiko; ISHIKAWA, Shingo; NAGATA, Shun-ichi; HOBO, Seiji

    2015-01-01

    To determine the intrapulmonary concentration of enrofloxacin (ERFX) in calves, plasma, bronchoalveolar lavage fluid (BALF) and alveolar cells samples were obtained from clinically healthy calves. Four clinically healthy calves were administered a single dose of ERFX (5 mg/kg) by subcutaneous injection. Samples of plasma were obtained for each subjects at 0 (before administration), 1 and 2 hr after administration of ERFX. Samples of BALF were obtained from each subject at 0, 1 and 2 hr after administration of ERFX. This examination was conducted two times, one week apart. The mean EFRX concentrations in plasma at 1 and 2 hr after administration were l.23 and 1.29 µg/ml, respectively. The mean EFRX concentrations in pulmonary epithelial lining fluid (ELF) at 1 and 2 hr after administration 8.53 µg/ml and 9.42 µg/ml, respectively. The mean ERFX concentrations of alveolar cells in BALF at 1 and 2 hr after administration were 4.04 µg/ml and 5.19 µg/ml, respectively. These results suggest that the ERFX concentrations in ELF and alveolar cells concentrations in BALF at 1 and 2 hr after administration were higher than the plasma concentrations. PMID:26668174

  18. Revealing source signatures in ambient BTEX concentrations

    International Nuclear Information System (INIS)

    Zalel, Amir; Yuval; Broday, David M.

    2008-01-01

    Management of ambient concentrations of Volatile Organic Compounds (VOCs) is essential for maintaining low ozone levels in urban areas where its formation is under a VOC-limited regime. The significant decrease in traffic-induced VOC emissions in many developed countries resulted in relatively comparable shares of traffic and non-traffic VOC emissions in urban airsheds. A key step for urban air quality management is allocating ambient VOC concentrations to their pertinent sources. This study presents an approach that can aid in identifying sources that contribute to observed BTEX concentrations in areas characterized by low BTEX concentrations, where traditional source apportionment techniques are not useful. Analysis of seasonal and diurnal variations of ambient BTEX concentrations from two monitoring stations located in distinct areas reveal the possibility to identify source categories. Specifically, the varying oxidation rates of airborne BTEX compounds are used to allocate contributions of traffic emissions and evaporative sources to observed BTEX concentrations. - BTEX sources are identified from temporal variations of ambient concentration

  19. Oxygen concentration inside a functioning photosynthetic cell.

    Science.gov (United States)

    Kihara, Shigeharu; Hartzler, Daniel A; Savikhin, Sergei

    2014-05-06

    The excess oxygen concentration in the photosynthetic membranes of functioning oxygenic photosynthetic cells was estimated using classical diffusion theory combined with experimental data on oxygen production rates of cyanobacterial cells. The excess oxygen concentration within the plesiomorphic cyanobacterium Gloeobactor violaceus is only 0.025 μM, or four orders of magnitude lower than the oxygen concentration in air-saturated water. Such a low concentration suggests that the first oxygenic photosynthetic bacteria in solitary form could have evolved ∼2.8 billion years ago without special mechanisms to protect them against reactive oxygen species. These mechanisms instead could have been developed during the following ∼500 million years while the oxygen level in the Earth's atmosphere was slowly rising. Excess oxygen concentrations within individual cells of the apomorphic cyanobacteria Synechocystis and Synechococcus are 0.064 and 0.25 μM, respectively. These numbers suggest that intramembrane and intracellular proteins in isolated oxygenic photosynthetic cells are not subjected to excessively high oxygen levels. The situation is different for closely packed colonies of photosynthetic cells. Calculations show that the excess concentration within colonies that are ∼40 μm or larger in diameter can be comparable to the oxygen concentration in air-saturated water, suggesting that species forming colonies require protection against reactive oxygen species even in the absence of oxygen in the surrounding atmosphere. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  20. Soil dioxin concentrations in Baden-Wuerttemberg

    International Nuclear Information System (INIS)

    Wolf, D.

    1993-01-01

    Soil dioxin levels in Baden-Wuerttemberg are generally low. Where high dioxin concentrations have been reported like in Rastatt, Rheinfelden, Crailsheim-Maulach and Eppingen these phenomena are local. Already at less than 100 metres distance, drastically lower concentrations are measured. At 1500 to 2000 metres distance the values are back to the ordinary background level. A programme for detecting sources of emission in the entire state revealed no further sites of heavy contamination. For this assessment of soil dioxin concentrations in Baden-Wuerttemberg 1275 soil samples were used, which is a vast amount also in comparison with nation-wide surveys. The average dioxin content in farmland is about 1 ng I-TEq/kg m T . Soil dioxin concentrations are the higher the greater the density of settlements and industry. In cities they are about three to five times higher than the ubiquitous background concentration. The highest concentrations measured were 5-20 ng I-TE/kg in garden soils in cities. Sewage sludge may be a significant source of dioxin contamination for farmland, far beyond the ubiquitous background concentration. Automobile exhaust gas caused higher soil contamination within 10 m along both sides of the roads as a function of traffic. Because scavengers in gasoline are now prohibited and catalysts are becoming more and more common the rate of additional dioxin and furan contamination due to traffic will decrease. Currently, traffic-related emissions in Baden-Wuerttemberg are well below 2 g I-TEq. (orig./EF) [de

  1. Highly concentrated zinc oxide nanocrystals sol with strong blue emission

    International Nuclear Information System (INIS)

    Vafaee, M.; Sasani Ghamsari, M.; Radiman, S.

    2011-01-01

    Highly concentrated ZnO sol was synthesized by an improved sol-gel method. Water was used as a modifier to control the sol-gel reaction and provide a way to increase the sol concentration. Concentration of ZnO in the prepared sol is higher than from other methods. Optical absorption and photoluminescence were used to investigate optical properties of the prepared sol. FTIR test was performed to study the influence of water on the compounds of as-prepared sol. The size and morphology of ZnO nanoparticles have been studied by HRTEM. The prepared colloidal ZnO nanocrystals have narrow size distribution (5-8 nm) and showed strong blue emission. The prepared sol has enough potential for optoelectronic applications. - Research highlights: → Novel sol-gel route has been employed to prepare highly concentrated ZnO colloidal nanocrystals. → Water has been used to control the sources of emission in synthesized material. → A strong blue luminescent material has been obtained.

  2. REVERSE OSMOSIS CONCENTRATION OF ORANGE JUICE USING SPIRAL WOUND MEMBRANES

    Directory of Open Access Journals (Sweden)

    W. A. de ARAUJO

    2009-03-01

    Full Text Available

    Flavor and odor components of foods are often lost during processing which leads to a poorer quality final product compared with the fresh ingredients. The orange juice industry concentrates juice (45-66ºBrix in TASTE (Thermally Accelerated Short Time Evaporator to remove excess water, and thus reduce storage and transportation costs, but also to improve product stability. Evaporation results in a loss of fresh juice flavors, color degradation and “cooked” taste due to the thermal effects. Methods using less heat for thermal damage reduction must be investigated to establish parameters for future commercial processes. The promising alternative is Reverse Osmosis (RO, but it cannot achieve concentrations greater than 30ºBrix. RO has advantages over traditional evaporation techniques in removing water. Because less heat is used, thermal damage to products is generally eliminated. In this project tests were performed using unpasteurised Single Strength Orange Juice (SSOJ, spiral wound membranes (Polyamide, and a DESAL pilot system model 4040. The aim was to evaluate spiral wound membranes on the basis of flux as a function of time. Retentate concentrations were 15-20ºBrix, and GC-FID analyses were used in order to understand aroma losses. KEYWORDS: Orange; juice; membrane; concentration; osmosis; reverse.

  3. Variation in caffeine concentration in single coffee beans.

    Science.gov (United States)

    Fox, Glen P; Wu, Alex; Yiran, Liang; Force, Lesleigh

    2013-11-13

    Twenty-eight coffee samples from around the world were tested for caffeine levels to develop near-infrared reflectance spectroscopy (NIRS) calibrations for whole and ground coffee. Twenty-five individual beans from five of those coffees were used to develop a NIRS calibration for caffeine concentration in single beans. An international standard high-performance liquid chromatography method was used to analyze for caffeine content. Coffee is a legal stimulant and possesses a number of heath properties. However, there is variation in the level of caffeine in brewed coffee and other caffeinated beverages. Being able to sort beans on the basis of caffeine concentration will improve quality control in the level of caffeine in those beverages. The range in caffeine concentration was from 0.01 mg/g (decaffeinated coffee) to 19.9 mg/g (Italian coffee). The majority of coffees were around 10.0-12.0 mg/g. The NIRS results showed r(2) values for bulk unground and ground coffees were >0.90 with standard errors coffee beans. One application of this calibration could be sorting beans on caffeine concentration to provide greater quality control for high-end markets. Furthermore, bean sorting may open new markets for novel coffee products.

  4. Rapid and sensitive determination of deuterium concentration by gas chromatography

    International Nuclear Information System (INIS)

    Takahashi, Tomiki; Ohokoshi, Sumio; Shinriki, Nariko; Sato, Toshio

    1984-01-01

    Gas chromatographic determination of hydrogen isotopes D 2 and HD has hitherto been carried out with a molecular sieve column kept at -195 0 C under the H 2 carrier gas. However, the amount of D 2 in hydrogen gas containing low HD concentration of less than 5 % can be practically neglected judging from the equilibrium constant of H 2 -D 2 exchange reaction. Therefore, there is no need to separate HD from D 2 . As an improvement, in this paper, the gas chromatographic determination of HD in low concentration ( 2 as a carrier gas enabled us to enhance the cell current of TCD drastically, hence gave rise to high sensitivity of HD detection. The limit of determination of the concentration of HD was 0.01%. In the case of the higher concentration (>5%) of HD in hydrogen gas, D 2 and HD have been separated and determined by the method described above, but this method takes more than ten minutes. Therefore, we designed a new gas chromatographic analysis of the HD-D 2 mixture with an activated alumina column at -195 0 C under the H 2 carrier gas (330 ml/min). The advantages of this method are in (1) rapid analysis (in 1 min), (2) no need of the rigid activation temperature ((110--250) 0 C), (3) no change of the relative molar sensitivity of HD to D 2 at the various flow rates of H 2 carrier gas ((100--300)ml/min). (author)

  5. Seasonal variation of radon concentrations in UK homes

    International Nuclear Information System (INIS)

    Miles, J C H; Howarth, C B; Hunter, N

    2012-01-01

    The patterns of seasonal variation of radon concentrations were measured in 91 homes in five regions of the UK over a period of two years. The results showed that there was no significant difference between the regions in the pattern or magnitude of seasonal variation in radon concentrations. The arithmetic mean variation was found to be close to that found previously in the UK national survey. Differences in the pattern between the two years of the study were not significant. Two-thirds of homes in the study followed the expected pattern of high radon in the winter and low radon in the summer. Most of the rest showed little seasonal variation, and a few showed a reversed seasonal pattern. The study does not provide any clear evidence for the recorded house characteristics having an effect on the seasonal variation in radon concentrations in UK homes, though the statistical power for determining such effects is limited in this study. The magnitude of the seasonal variation varied widely between homes. Analysis of the individual results from the homes showed that because of the wide variation in the amount of seasonal variation, applying seasonal correction factors to the results of three-month measurements can yield only relatively small improvements in the accuracy of estimates of annual mean concentrations.

  6. Characteristic and comparison of different submounts on concentrating photovoltaic module

    Science.gov (United States)

    Lee, Yueh-Mu; Shih, Zun-Hao; Hong, Hwen-Fen; Shin, Hwa-Yuh; Kuo, Cherng-Tsong

    2014-09-01

    High concentration photovoltaics systems employ concentrating optics consisting of dish reflectors or fresnel lenses that concentrate sunlight to 500 suns or more. In general, under concentrating light operation condition, the device temperature rises quickly and the open-circuit voltage of solar cell will decrease with increasing temperature; therefore, the system output power or energy-conversion efficiency will decrease while temperature of solar cell increased. In this study, we analyze the ceramic thermal resistance and propose a direct temperature measurement method of the solar cell. The direct temperature measurement of the cell and the ceramic was achieved by utilizing buried thermocouples with a diameter of 50 μm between the cell/ceramic and aluminum plate. The different light flux densities ranging from 500 to 800 W/m2 at 100 W/m2 interval by solar simulator are provided to measure temperature, and the cell temperatures measured are 39.8 °C, 41 °C, 45 °C and 48 °C, respectively. The temperature differences between the cell and aluminum plate of the light flux densities from 500 W/m2 to 800 W/m2 are in the range of 4.2 °C to 8 °C. Accordingly we can obtain the temperature distribution of HCPV module at difference region. The results can help us to optimize module package technology and to choose better material applied to the module to improve conversion efficiency of the cell.

  7. Hydrophobicity and charge shape cellular metabolite concentrations.

    Directory of Open Access Journals (Sweden)

    Arren Bar-Even

    2011-10-01

    Full Text Available What governs the concentrations of metabolites within living cells? Beyond specific metabolic and enzymatic considerations, are there global trends that affect their values? We hypothesize that the physico-chemical properties of metabolites considerably affect their in-vivo concentrations. The recently achieved experimental capability to measure the concentrations of many metabolites simultaneously has made the testing of this hypothesis possible. Here, we analyze such recently available data sets of metabolite concentrations within E. coli, S. cerevisiae, B. subtilis and human. Overall, these data sets encompass more than twenty conditions, each containing dozens (28-108 of simultaneously measured metabolites. We test for correlations with various physico-chemical properties and find that the number of charged atoms, non-polar surface area, lipophilicity and solubility consistently correlate with concentration. In most data sets, a change in one of these properties elicits a ~100 fold increase in metabolite concentrations. We find that the non-polar surface area and number of charged atoms account for almost half of the variation in concentrations in the most reliable and comprehensive data set. Analyzing specific groups of metabolites, such as amino-acids or phosphorylated nucleotides, reveals even a higher dependence of concentration on hydrophobicity. We suggest that these findings can be explained by evolutionary constraints imposed on metabolite concentrations and discuss possible selective pressures that can account for them. These include the reduction of solute leakage through the lipid membrane, avoidance of deleterious aggregates and reduction of non-specific hydrophobic binding. By highlighting the global constraints imposed on metabolic pathways, future research could shed light onto aspects of biochemical evolution and the chemical constraints that bound metabolic engineering efforts.

  8. Aspects of reduction clorination of pyrochlore concentrates

    International Nuclear Information System (INIS)

    Gameiro, D.H.; Brocchi, E.A.

    1985-01-01

    Reduction chlorination experiments were carried out with two different Brazilian pyrochlore concentrates in order to evaluate the effects of some variables on the extent of niobium pentoxide gaseification as well as to compare the behavior of concentrate under the same chlorination conditions. The pyrochlore concentrates from Araxa (MG) and Catalao (GO), Brazil, were submitted to X ray diffraction and X ray fluorescence analysis for determining their chemical compositions. Kinetic curves were obtained with the main variables being temperature and percentage of reducing agent. Analysis of the condensed material in terms of Nb 2 O 5 indicated that chlorination can be used to produce niobium pentoxide. (Author) [pt

  9. Concentrated sunlight for organic solar cells

    DEFF Research Database (Denmark)

    Tromholt, Thomas

    2010-01-01

    . A high solar intensity study of inverted P3HT:PCBM solar cells is presented. Performance peak positions were found to be in the range of 1-5 suns, with smaller cells peaking at higher solar concentrations. Additionally, concentrated sunlight is demonstrated as a practical tool for accelerated stability...... were degraded resulting in acceleration factors in the range of 19-55. This shows that concentrated sunlight can be used as qualitatively to determine the lifetime of polymers under highly accelerated conditions....

  10. Plasma fibronectin concentrations in morbidly obese patients

    DEFF Research Database (Denmark)

    Dejgaard, A; Andersen, T; Christoffersen, Pernille Yde

    1984-01-01

    Plasma fibronectin concentrations and liver morphology were investigated in 45 morbidly obese subjects (median overweight 88%) and in 42 normal weight controls, matched for sex and age. A significantly (P less than 0.01) raised plasma fibronectin concentration (median 464 mg/l, range 276-862 mg...... in their liver biopsies (r = 0.33, P less than 0.05). Significantly (P less than 0.05) elevated plasma fibronectin concentrations even in obese subjects without hepatic fatty change indicate that liver fat accumulation is no prerequisite of the obesity-related elevation of plasma fibronectin. Raised plasma...

  11. Indoor radon concentration forecasting in South Tyrol

    International Nuclear Information System (INIS)

    Verdi, L.; Weber, A.; Stoppa, G.

    2004-01-01

    In this paper a modern statistical technique of multivariate analysis is applied to an indoor radon concentration database. Several parameters are more or less significant in determining the radon concentration inside a building. The elaboration of the information available on South Tyrol makes it possible both to identify the statistically significant variables and to build up a statistical model that allows us to forecast the radon concentration in dwellings, when the values of the same variables involved are given. The results confirm the complexity of the phenomenon. (authors)

  12. Sucralfate significantly reduces ciprofloxacin concentrations in serum.

    OpenAIRE

    Garrelts, J C; Godley, P J; Peterie, J D; Gerlach, E H; Yakshe, C C

    1990-01-01

    The effect of sucralfate on the bioavailability of ciprofloxacin was evaluated in eight healthy subjects utilizing a randomized, crossover design. The area under the concentration-time curve from 0 to 12 h was reduced from 8.8 to 1.1 micrograms.h/ml by sucralfate (P less than 0.005). Similarly, the maximum concentration of ciprofloxacin in serum was reduced from 2.0 to 0.2 micrograms/ml (P less than 0.005). We conclude that concurrent ingestion of sucralfate significantly reduces the concentr...

  13. Luminescent solar concentrators with fiber geometry.

    Science.gov (United States)

    Edelenbosch, Oreane Y; Fisher, Martyn; Patrignani, Luca; van Sark, Wilfried G J H M; Chatten, Amanda J

    2013-05-06

    The potential of a fibre luminescent solar concentrator has been explored by means of both analytical and ray-tracing techniques. Coated fibres have been found to be more efficient than homogeneously doped fibres, at low absorption. For practical fibres concentration is predicted to be linear with fibre length. A 1 m long, radius 1 mm, fibre LSC doped with Lumogen Red 305 is predicted to concentrate the AM1.5 g spectrum up to 1100 nm at normal incidence by ~35 x. The collection efficiency under diffuse and direct irradiance in London has been analysed showing that, even under clear sky conditions, in winter the diffuse contribution equals the direct.

  14. Determination of particle concentrations in multitemperature plasmas

    International Nuclear Information System (INIS)

    Richley, E.; Tuma, D.T.

    1982-01-01

    The use of the multitemperature Saha equation (MSE) of Prigogine 1 and Patapov 2 for calculating particle concentrations in plasmas is shown to be an invalid procedure. Errors greater than one order of magnitude in the electron density in high-pressure argon and nitrogen electric arc plasmas can be easily incurred by using the multitemperature Saha equation. The alternative kinetic method for calculating concentrations is shown to be based on firm concepts. Simpliying procedures and computational techniques for calculating concentrations with the kinetic method are illustrated with examples

  15. Computational algorithm for molybdenite concentrate annealing

    International Nuclear Information System (INIS)

    Alkatseva, V.M.

    1995-01-01

    Computational algorithm is presented for annealing of molybdenite concentrate with granulated return dust and that of granulated molybdenite concentrate. The algorithm differs from the known analogies for sulphide raw material annealing by including the calculation of return dust mass in stationary annealing; the latter quantity varies form the return dust mass value obtained in the first iteration step. Masses of solid products are determined by distribution of concentrate annealing products, including return dust and benthonite. The algorithm is applied to computations for annealing of other sulphide materials. 3 refs

  16. Body and Gender in Nazi Concentration Camps

    Directory of Open Access Journals (Sweden)

    Bożena Karwowska

    2009-01-01

    Full Text Available The article Body and Gender in Nazi Concentration Camps is an attempt to discuss difficult issues of human sexuality and sexually marked behaviors in the context of the concentration camps, and their descriptions in the memoirs of the survivors. Using notions and concepts of the so called "black American feminism" the author (referring extensively to books by Stanisław Grzesiuk and Zofia Romanowiczowa shows how in the concentration camp the human body became the only space of a relative privacy of the prisoner. At the same time the body becomes a territory on which all - both biological and socially constructed - human fates cross.

  17. Maximum permissible concentrations and negligible concentrations for antifouling substances. Irgarol 1051, dichlofluanid, ziram, chlorothalonil and TCMTB

    NARCIS (Netherlands)

    Wezel AP van; Vlaardingen P van; CSR

    2001-01-01

    This report presents maximum permissible concentrations and negligible concentrations that have been derived for various antifouling substances used as substitutes for TBT. Included here are Irgarol 1051, dichlofluanide, ziram, chlorothalonil and TCMTB.

  18. Design optimization studies for nonimaging concentrating solar collector tubes

    Science.gov (United States)

    Winston, R.; Ogallagher, J. J.

    1983-09-01

    The Integrated Stationary Evacuated Concentrator or ISEC solar collector panel which achieved the best high temperature performance ever measured with a stationary collector was examined. A development effort review and optimize the initial proof of concept design was completed. Changes in the optical design to improve the angular response function and increase the optical efficiency were determined. A recommended profile design with a concentration ratio of 1.55x and an acceptance angle of + - 35(0) was identified. Two alternative panel/module configurations are recommended based on the preferred double ended flow through design. Parasitic thermal and pumping losses show to be reducible to acceptable levels, and two passive approaches to the problem of ensuring stagnation survival are identified.

  19. Spatial variations in nitrogen dioxide concentrations in urban Ljubljana, Slovenia

    Directory of Open Access Journals (Sweden)

    Vintar Mally Katja

    2015-09-01

    Full Text Available Ambient nitrogen dioxide (NO2 concentrations are regularly measured at only two monitoring stations in the city centre of Ljubljana, and such scanty data are inadequate for drawing conclusions about spatial patterns of pollution within the city, or to decide on effective measures to further improve air quality. In order to determine the spatial distribution of NO2 concentrations in different types of urban space in Ljubljana, two measuring campaigns throughout the city were carried out, during the summer of 2013 and during the winter of 2014. The main source of NO2 in Ljubljana is road transport. Accordingly, three types of urban space have been identified (urban background, open space along roads, and street canyon, and their NO2 pollution level was measured using Palmes diffusive samplers at a total of 108 measuring spots. This article analyses the results of both measuring campaigns and compares the pollution levels of different types of urban space.

  20. A Compound Detection System Based on Ultrasonic Flow Rate and Concentration

    Directory of Open Access Journals (Sweden)

    Qing-Hui WANG

    2014-02-01

    Full Text Available This paper proposes a new detection system for monitoring gas concentration and flow rate. Velocity difference of ultrasonic wave in bi-directional propagation in measured gas is recorded and utilized for computing the online gas concentration and flow rate. Meanwhile, the temperature compensation, return signal processing and error analysis algorithms are applied to improve the accuracy. The experimental results show that, compared with the single sensor measurement of gas flow rate or concentration, the proposed detection system with lower cost and higher accuracy can be applied in the occasion which needs simultaneous monitoring of gas concentration and flow rate.

  1. Change of Exhaled Acetone Concentration in a Diabetic Patient with Acute Decompensated Heart Failure.

    Science.gov (United States)

    Yokokawa, Tetsuro; Ichijo, Yasuhiro; Houtsuki, Yu; Matsumoto, Yoshiyuki; Oikawa, Masayoshi; Yoshihisa, Akiomi; Sugimoto, Koichi; Nakazato, Kazuhiko; Suzuki, Hitoshi; Saitoh, Shu-Ichi; Shimouchi, Akito; Takeishi, Yasuchika

    2017-10-21

    In heart failure patients, exhaled acetone concentration, a noninvasive biomarker, is increased according to heart failure severity. Moreover, exhaled acetone concentration is also known to be affected by diabetes mellitus. However, there have been no reports on exhaled acetone concentration in heart failure patients with diabetes mellitus. A 77-year old man was admitted to our hospital with acute decompensated heart failure and atrioventricular block. He had controlled diabetes mellitus under insulin treatment with hemoglobin A1c of 6.5%. He underwent treatment of diuretics and permanent pacemaker implantation. His condition improved and he was discharged at Day 12. Due to the heart failure improvement, his levels of exhaled acetone concentration decreased from 1.623 ppm at admission to 0.664 ppm at discharge. This is the first report to reveal a change of exhaled acetone concentration in a diabetic patient with acute decompensated heart failure.

  2. Experimental investigations into low concentrating line axis solar concentrators for CPV applications

    OpenAIRE

    Singh, H; Sabry, M; Redpath, DAG

    2016-01-01

    Solar photovoltaic conversion systems with integrated, low concentration ratio, non-imaging reflective concentrators, could be on south facing building roofs used to generate power at a lower cost than currently available proprietary systems. The experimental investigation presented by this research provides information on the optical and energy conversion characteristics of two geometrically equivalent non-imaging concentrators; a compound parabolic concentrator and a V-trough reflector. The...

  3. Uranium recovery from phosphate rocks concentrated

    International Nuclear Information System (INIS)

    Azevedo, M.F. de.

    1986-01-01

    The reserves, geological data, chemical data and technical flowsheet from COPEBRAS and Goiasfertil ores are described, including the process of mining ore concentration. Samples of Goiasfertil ores are analysed by gravimetric analysis, for phosphate, and spectrofluorimetry for uranium. (author)

  4. Characterization of high concentration dust generator

    International Nuclear Information System (INIS)

    Shimura, Toichiro; Yokochi, Akira

    1999-01-01

    This paper describes the development of fluidized bed type high concentration dust generator that keeps for long period dust concentration range of about 10 mg/m 3 for the study of working place monitoring system and evaluation of respirator. The generator is keeping constant powder in fluidized bed for keeping the dust concentration. It is necessary to keep constant feeding rate of powder in order to keep the quantity of dust in the fluidized bed. Our generator enables to obtain constant feeding rate by a screw feeder and by using mixed powder with fluidising particles (glass beads) before feeding. The generator produces high concentration dust of 11.3 mg/m 3 ± 1.0 mg/m 3 for about 5 hours and keeps the dust size 4.2-4.6 μm in mass median aerodynamic diameter with reasonable reproducibility. (author)

  5. Arctic and Southern Ocean Sea Ice Concentrations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly sea ice concentration for Arctic (1901 to 1995) and Southern oceans (1973 to 1990) were digitized on a standard 1-degree grid (cylindrical projection) to...

  6. Indoor radon concentrations in Vushtrri, Kosovo

    International Nuclear Information System (INIS)

    Xhafa, B.; Jonuzaj, A.; ); Bekteshi, S.; Ahmetaj, S.; Kabashi, S.; )

    2009-01-01

    Indoor air radon concentration was measured by exposing trac ketch detectors in the two elementary schools, one high school, a kindergarten and the hospital in the city of Vushtrri. Measurements were performed with the radon monitor PRM-145, which uses alpha scintillation cells and serves to determine the current concentration of radon. The results we obtained are in the range between the average values of radon for the interior spaces, and values that pose a potential risk for lung cancer. Measuring the concentration of radon was done in total of 34 rooms and came up with values which are between 28Bqm -3 and 398Bqm -3 . In order to reduce the concentration of radon, we have built a ventilation pump, then we performed repeated measurements and finally came with results between 130-145Bqm -3 .

  7. Advancing Concentrating Solar Power Research (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2014-02-01

    Researchers at the National Renewable Energy Laboratory (NREL) provide scientific, engineering, and analytical expertise to help advance innovation in concentrating solar power (CSP). This fact sheet summarizes how NREL is advancing CSP research.

  8. ISLSCP II Globalview: Atmospheric CO2 Concentrations

    Data.gov (United States)

    National Aeronautics and Space Administration — The GlobalView Carbon Dioxide (CO2) data product contains synchronized and smoothed time series of atmospheric CO2 concentrations at selected sites that were created...

  9. THE IMPACT OF HEAVY METAL CONCENTRATION ON

    African Journals Online (AJOL)

    Temitope

    Index of geo-accumulation (Igeo), revealed no contamination of the trace metals. ... (Hg), arsenic (As) and cadmium (Cd). ... standards, and to suggest the best remedial methods ..... metal concentrations in urban soil of Ibadan metropolis,.

  10. Process for treatment of pyrochlore concentrates

    International Nuclear Information System (INIS)

    Charlot, G.

    1976-01-01

    A continuous process is described for extraction of niobium, rare earths and thorium from niobium ore concentrates which includes digesting the ore with a hot solution containing 13 to 16 moles of sulphuric acid per liter, diluting the solution to a concentration of 10 to 13 moles of sulphuric acid per liter, separating the insolubles from the solution which includes alkaline earth sulphates and the sulphates of thorium and rare earths that are present, reducing titanium in solution to the trivalent state and diluting the solution to a concentration of 5 to 7 moles of sulphuric acid per liter, separating the precipitated niobium oxide and sulphates of thorium and rare earths, and then concentrating the resulting solution to the level desired for recycle to the digestion stage. 10 Claims, No Drawings

  11. Seasonal Composite Chlorophyll Concentrations - Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of chlorophyll concentrations in the Gulf of Maine. These raster images are seasonal composites, and were calculated...

  12. Concentration of stable elements in food products

    International Nuclear Information System (INIS)

    Montford, M.A.; Shank, K.E.; Hendricks, C.; Oakes, T.W.

    1980-01-01

    Food samples were taken from commercial markets and analyzed for stable element content. The concentrations of most stable elements (Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hf, I, K, La, Mg, Mn, Mo, Na, Rb, Sb, Sc, Se, Sr, Ta, Th, Ti, V, Zn, Zr) were determined using multiple-element neutron activation analysis, while the concentrations of other elements (Cd, Hg, Ni, Pb) were determined using atomic absorption. The relevance of the concentrations found are noted in relation to other literature values. An earlier study was extended to include the determination of the concentration of stable elements in home-grown products in the vicinity of the Oak Ridge National Laboratory. Comparisons between the commercial and local food-stuff values are discussed

  13. Nonimaging concentrators for photovoltaic arrays in space

    Science.gov (United States)

    Winston, R.; Greenman, P.; Rockey, D.

    1981-01-01

    Two stage concentrators are studied in order to design an optimum concentrator for photovoltaic arrays in space. The study is directed at designs with two-dimensional geometries because they are better suited to moderate concentrations of about 10 X to 50 X, and because the instantaneous flux distribution is more uniform. It is found that with an f/0.5 primary, where f is the focal length of the primary, the flux distribution is very smooth regardless of the angle of incidence of the radiation. As the focal ratio is increased, peaks in the distribution begin to appear. The nonuniformities can be reduced by introducing small, closely spaced distortions into the reflecting surfaces, and practical arrays can achieve a concentration of 10 when the acceptance half angle is 4.25 deg or 50 when the acceptance half angle is + or - 1 deg.

  14. [Nitrate concentrations in tap water in Spain].

    Science.gov (United States)

    Vitoria, Isidro; Maraver, Francisco; Sánchez-Valverde, Félix; Armijo, Francisco

    2015-01-01

    To determine nitrate concentrations in drinking water in a sample of Spanish cities. We used ion chromatography to analyze the nitrate concentrations of public drinking water in 108 Spanish municipalities with more than 50,000 inhabitants (supplying 21,290,707 potential individuals). The samples were collected between January and April 2012. The total number of samples tested was 324. The median nitrate concentration was 3.47 mg/L (range: 0.38-66.76; interquartile range: 4.51). The water from 94% of the municipalities contained less than 15 mg/L. The concentration was higher than 25mg/L in only 3 municipalities and was greater than 50mg/L in one. Nitrate levels in most public drinking water supplies in municipalities inhabited by almost half of the Spanish population are below 15 mg/L. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  15. Familial Resemblance for Serum Metabolite Concentrations

    NARCIS (Netherlands)

    Draisma, H.H.M.; Beekman, M.; Pool, R.; van Ommen, G.J.B; Vaarhorst, A.A.M.; de Craen, A.J.; Willemsen, G.; Slagboom, P.E.; Boomsma, D.I.

    2013-01-01

    Metabolomics is the comprehensive study of metabolites, which are the substrates, intermediate, and end products of cellular metabolism. The heritability of the concentrations of circulating metabolites bears relevance for evaluating their suitability as biomarkers for disease. We report aspects of

  16. Monitoring of radon concentration in dwellings

    International Nuclear Information System (INIS)

    Kurosawa, Ryuhei

    1991-01-01

    Radon problems in dwellings have recently received much attention. Radon concentration in dwellings, as well as in the general environment, varies with various factors such as meteorological conditions and soil components. Therefore, a long term monitoring of radon concentration is required to obtain an average concentration. This paper reviews a passive type radon monitor that is handy and allows a long term radon monitoring. It provides the structure and principle of the radon monitor, covering the type, filter function, sensitivity of diffusion collecting type (cup type), electrostatic collecting type, adsorption collecting type, and detector of radon monitor. Actual examples of the radon monitor are also given. Radon daughter nuclides will have become major foci of exposure countermeasures. In the future, the development of a passive type monitor for determining potential alpha energy concentration is required. (N.K.)

  17. Odor concentration invariance by chemical ratio coding

    Directory of Open Access Journals (Sweden)

    Naoshige Uchida

    2008-08-01

    Full Text Available Many animal species rely on chemical signals to extract ecologically important information from the environment. Yet in natural conditions chemical signals will frequently undergo concentration changes that produce differences in both level and pattern of activation of olfactory receptor neurons. Thus, a central problem in olfactory processing is how the system is able to recognize the same stimulus across different concentrations. To signal species identity for mate recognition, some insects use the ratio of two components in a binary chemical mixture to produce a code that is invariant to dilution. Here, using psychophysical methods, we show that rats also classify binary odor mixtures according to the molar ratios of their components, spontaneously generalizing over at least a tenfold concentration range. These results indicate that extracting chemical ratio information is not restricted to pheromone signaling and suggest a general solution for concentration-invariant odor recognition by the mammalian olfactory system.

  18. Stress concentration effects in high pressure components

    International Nuclear Information System (INIS)

    Aller, J.E.

    1990-01-01

    This paper examines the stress concentration effects of sideholes in thick walled, high pressure cylinders. It has been shown that the theoretical stress concentration factor at the intersection of a small crossbore in a closed end, thick walled cylinder varies between 3.0 and 4.0. Tests have shown that this effect can be greatly reduced in practice by carefully radiusing the bore intersection and autofrettaging the cylinder. It has also been shown that the minimum stress concentration factor occurs when the main bore and sidehole or crossbore have the same diameter, and the radius of the intersection is approximately equal to the sidehole radius. When the bore and sidehole intersection angle decreases from 90 degrees, the stress concentration factor increases significantly. Knowledge of these fundamental relationships can be used in maintaining, as well ad designing, high pressure equipment

  19. Concentration variation of radon in the room

    International Nuclear Information System (INIS)

    Komaruzaman Mohd Noor; Haziman Hassan; Rosli Mahat; Yusof Md Amin

    1995-01-01

    The study was carried out to determine the variation of radon concentration in the room. Radon detector used was solid nuclear tracks detector (SSNTD) LR-115. From this result, suitable points to make radon measurement was determined

  20. Monthly Composite Chlorophyll Concentrations - Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of chlorophyll concentrations in the Gulf of Maine. These raster images are monthly composites, and were calculated...

  1. Maximum phytoplankton concentrations in the sea

    DEFF Research Database (Denmark)

    Jackson, G.A.; Kiørboe, Thomas

    2008-01-01

    A simplification of plankton dynamics using coagulation theory provides predictions of the maximum algal concentration sustainable in aquatic systems. These predictions have previously been tested successfully against results from iron fertilization experiments. We extend the test to data collect...

  2. Building integrated concentrating photovoltaics: A review

    International Nuclear Information System (INIS)

    Chemisana, Daniel

    2011-01-01

    For building integration, Concentrating Photovoltaic (CPV) systems can offer a host of advantages over conventional flat panel devices, the most notable being: a higher electrical conversion efficiency in the PV cells, better use of space, ease of recycling of constituent materials, and reduced use of toxic products involved in the PV cells' production process. However, the viability of Building-Integrated Concentrating PV (BICPV) systems is dependent on their ability to offer a comparative economic advantage over flat panel photovoltaic technologies whose market prices are decreasing from day to day and which offer other advantages such as ease of replacement of structural elements. A comparative analysis is presented of the main existing CPV systems' suitability for use in buildings, in which the different challenges specific to integration of each system are discussed. The systems are categorized by type of concentration technology and concentration factor. (author)

  3. Concentration changes due to cathodic protection

    NARCIS (Netherlands)

    Gellings, P.J.

    1978-01-01

    By solving the appropriate diffusion equations the concentration changes are calculated in the environment of underground structures protected cathodically. It is shown that these changes are negligible under all practical circumstances.

  4. Bioaerosol concentrations - Figure 3 and Figure 4

    Data.gov (United States)

    U.S. Environmental Protection Agency — Bioaerosol concentrations. This dataset is associated with the following publication: Chattopadhyay, S., S. Perkins, M. Shaw, and T. Nichols. Evaluation of Exposure...

  5. 7746 CONCENTRATIONS OF FORMALDEHYDE IN RAIN WATERS ...

    African Journals Online (AJOL)

    Win7Ent

    2013-06-03

    Jun 3, 2013 ... The chromotropic acid method described by the. National Institute for ... concentration range of the formaldehyde in the rain waters varied from month to month throughout the six ... vicinity of vegetation [3]. Formaldehyde is the ...

  6. Concentration quenching in Nd-doped glasses

    International Nuclear Information System (INIS)

    Stokowski, S.E.; Cook, L.; Mueller, H.; Weber, M.J.

    1984-01-01

    Fluorescence from trivalent Nd in solids is unfortunately quenched by interactions between Nd ions. Thus, laser materials with high Nd concentrations have reduced efficiencies because of this self-quenching, also known as concentration quenching. Nd self-quenching in different crystals and glasses varies considerably. We are therefore investigating this effect in a large number of materials in an effort to: (1) find those materials with long Nd fluorescent lifetimes at high Nd concentrations; and (2) elucidate the basic mechanisms of quenching and how the material structure controls its magnitude. We have concentrated on Nd-doped glasses because they provide a rich variety of structures, albeit complicated by Nd site inhomogeneities, and are easily and quickly made

  7. Relations between fatty acid synthesis, pyruvate concentration and cell concentration of suspensions of isolated rat hepatocytes

    NARCIS (Netherlands)

    Beynen, A.C.; Geelen, M.J.H.

    1984-01-01

    1. 1. The cell concentration of suspensions of isolated rat hepatocytes affects both the rate of pyruvate accumulation in the incubation medium and the rate of fatty acid synthesis. 2. 2. At low cell concentrations pyruvate accumulation is directly related to the cell concentration but levels off

  8. Chromium concentrations in ruminant feed ingredients.

    Science.gov (United States)

    Spears, J W; Lloyd, K E; Krafka, K

    2017-05-01

    Chromium (Cr), in the form of Cr propionate, has been permitted for supplementation to cattle diets in the United States at levels up to 0.50 mg of Cr/kg of DM since 2009. Little is known regarding Cr concentrations naturally present in practical feed ingredients. The present study was conducted to determine Cr concentrations in feed ingredients commonly fed to ruminants. Feed ingredients were collected from dairy farms, feed mills, grain bins, and university research farms. Mean Cr concentrations in whole cereal grains ranged from 0.025 mg/kg of DM for oats to 0.041 mg/kg of DM for wheat. Grinding whole samples of corn, soybeans, and wheat through a stainless steel Wiley mill screen greatly increased analyzed Cr concentrations. Harvested forages had greater Cr concentrations than concentrates, and alfalfa hay or haylage had greater Cr concentrations than grass hay or corn silage. Chromium in alfalfa hay or haylage (n = 13) averaged 0.522 mg/kg of DM, with a range of 0.199 to 0.889 mg/kg of DM. Corn silage (n = 21) averaged 0.220 mg of Cr/kg of DM with a range of 0.105 to 0.441 mg of Cr/kg of DM. By-product feeds ranged from 0.040 mg of Cr/kg of DM for cottonseed hulls to 1.222 mg of Cr/kg of DM for beet pulp. Of the feed ingredients analyzed, feed grade phosphate sources had the greatest Cr concentration (135.0 mg/kg). Most ruminant feedstuffs and feed ingredients had less than 0.50 mg of Cr/kg of DM. Much of the analyzed total Cr in feed ingredients appears to be due to Cr contamination from soil or metal contact during harvesting, processing, or both. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. A method of uranium isotopes concentration analysis

    International Nuclear Information System (INIS)

    Lin Yuangen; Jiang Meng; Wu Changli; Duan Zhanyuan; Guo Chunying

    2010-01-01

    A basic method of uranium isotopes concentration is described in this paper. The iteration method is used to calculate the relative efficiency curve, by analyzing the characteristic γ energy spectrum of 235 U, 232 U and the daughter nuclide of 238 U, then the relative activity can be calculated, at last the uranium isotopes concentration can be worked out, and the result is validated by the experimentation. (authors)

  10. The hydrogen and deuterium concentrations in chondrites

    International Nuclear Information System (INIS)

    Robert, F.; Merlivat, L.

    1978-01-01

    Water and isotopic concentration of H 2 O + are reported. It shows a correlation between the water, the deuterium concentrations and the petrologic types of chondrites. The Chainpur meteorite has been divided into several mineralogical fractions and the results are reported. The results of Orgueil are also reported. The correlation shows that as the sulfate content increases, the water and deuterium contents decrease. The terrestrial contamination is discussed and possible deuterium variation models are presented

  11. Concentration of actinides in the food chain

    International Nuclear Information System (INIS)

    Bulman, R.A.

    1976-06-01

    Considerable concern is now being expressed over the discharge of actinides into the environment. This report presents a brief review of the chemistry of the actinides and examines the evidence for interaction of the actinides with some naturally-occurring chelating agents and other factors which might stimulate actinide concentration in the food chain of man. This report also reviews the evidence for concentration of actinides in plants and for uptake through the gastrointestinal tract. (author)

  12. Concentrated Photo Voltaics (CPV: a case study

    Directory of Open Access Journals (Sweden)

    Centro S.

    2015-01-01

    Full Text Available Concentrated PhotoVoltaic (CPV, among green energy solutions, nowadays has the ambition to reach grid-parity without subside. CPV substitutes large areas of expensive semiconductor solar cells, with concentrating optics made of cheap materials. Moreover the cells that are suitable for CPV exhibits an unprecedented efficiency and their technology is progressing every year. A case study project, TwinFocus®, will be presented in detail.

  13. Pressure drop in T's in concentric ducts

    International Nuclear Information System (INIS)

    Shock, R.A.W.

    1983-02-01

    A set of experiments has been carried out to measure the pressure drop characteristics of single-phase flow in dividing and joining right-angled T's in a concentric ducting system. These have been compared with measured pressure drops in a simple round tube system. In most tests with the concentric system the number of velocity heads lost is either similar to, or more than, the value for the round tubes. (author)

  14. Platelet Concentrates: Past, Present and Future

    OpenAIRE

    Prakash, Shobha; Thakur, Aditi

    2011-01-01

    Platelets play a crucial role in hemostasis and wound healing, platelet growth factors are well known source of healing cytokines. Numerous techniques of autologous platelet concentrates have been developed and applied in oral and maxillofacial surgery. This review describes the evolution of the first and second generation of platelet concentrates (platelet rich plasma and platelet rich fibrin respectively) from their fore runner-fibrin sealants.

  15. Radon concentration in a house of Calvados

    International Nuclear Information System (INIS)

    Leleyter, L.; Riffault, B.; Mazenc, B.

    2010-01-01

    Recent studies indicate a link between the risk of lung cancer and residential radon exposure. However, in France, awareness of this problem was made relatively late. Accordingly this study examines the radon concentration in a private home in Calvados (Normandy region). Findings show that the presence of a fireplace in a house can accelerate radon convective transfer, and that simple adjustments to interior and exterior accommodation can significantly reduce radon concentrations in the home. (authors)

  16. Quantification of Fluorine Content in AFFF Concentrates

    Science.gov (United States)

    2017-09-29

    for MilSpec compliance. Fluorocarbon surfactants are the most active components in these concentrates, and analysis of the fluorine content in the... physical requirements for AFFF concentrates includes a total fluorine content determination and a requirement for subsequent evaluations of this AFFF...the standard for fluorine content as well as the reference for chemical shift. For preparation of an NMR solution, it is important that the TFE

  17. Wave Front Sensor for Solar Concentrator Control

    Science.gov (United States)

    2009-10-01

    terrestrial-based and space-based. Both types of concentrator can be either imaging or nonimaging and they can be rigid or inflatable. Other...and T is the temperature of the absorber and propellant. In (5), Iin is input intensity with effects of the optical path through the concentrator acting...Hartmann in 1900 and was used for checking optical telescopes for aberrations. It was an array of holes in a plate placed in front of the mirror of

  18. Increased Mercury Bioaccumulation Follows Water Quality Improvement

    Energy Technology Data Exchange (ETDEWEB)

    Bogle, M.A.; Peterson, M.J.; Smith, J.G.; Southworth, G.R.

    1999-09-15

    Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the period during which ecological metrics indicated improved water quality. In the system where waterborne mercury concentrations were at background levels, increased mercury bioaccumulation was probably a result of reduced aqueous selenium concentrations; however, the mechanisms for increased mercury accumulation in the other two streams remain under investigation. In each of the three systems, reduced inputs of metals and inorganic anions was followed by improvements in the health of aquatic invertebrate communities. However, this reduction in risk to aquatic invertebrates was accompanied by increased risk to humans and piscivorous wildlife related to increased mercury concentrations in fish.

  19. Increased Mercury Bioaccumulation Follows Water Quality Improvement

    International Nuclear Information System (INIS)

    Bogle, M.A.; Peterson, M.J.; Smith, J.G.; Southworth, G.R.

    1999-01-01

    Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the period during which ecological metrics indicated improved water quality. In the system where waterborne mercury concentrations were at background levels, increased mercury bioaccumulation was probably a result of reduced aqueous selenium concentrations; however, the mechanisms for increased mercury accumulation in the other two streams remain under investigation. In each of the three systems, reduced inputs of metals and inorganic anions was followed by improvements in the health of aquatic invertebrate communities. However, this reduction in risk to aquatic invertebrates was accompanied by increased risk to humans and piscivorous wildlife related to increased mercury concentrations in fish

  20. Potassium concentration in bone of Beijing residents

    International Nuclear Information System (INIS)

    Lin Lianqing

    1994-01-01

    The author presents the measuring results of K concentration in bone ash samples of 65 residents in Beijing area by atomic absorption spectrum. The results indicate that the K concentrations in bone ash is logarithmic normal distribution, ranging level is 0.75-8.44 g/kg ash, the average and standard deviation is respectively 2.40 and 1.52 g/kg ash. The highest concentration (4.88 g/kg ash) appears in infantile stage (< 1y), the lowest concentration (1.59 g/kg ash) appears in young stage (2-5 y). The lower concentration (1.88 g/kg ash) appears in adolescence (11-20 y). The K concentration in wet bone as a percentage of weight is 0.067%. The specific activities of K-40 in bone is about 22 mBq/g wet bone. The total radioactivity of K-40 in whole bone is 220 Bq. The annual absorbed dose is received in adult bone from K-40 is estimated to be 95 μGy

  1. Uranium concentration monitor manual, secondary intermediate evaporator

    International Nuclear Information System (INIS)

    Russo, P.A.; Sprinkle, J.K. Jr.; Slice, R.W.; Strittmatter, R.B.

    1985-08-01

    This manual describes the design, operation, and measurement control procedures for the automated uranium concentration monitor on the secondary intermediate evaporator at the Oak Ridge Y-12 Plant. The nonintrusive monitor provides a near-real time readout of uranium concentration in the return loop of time recirculating evaporator for purposes of process monitoring and control. A detector installed near the bottom of the return loop is used to acquire spectra of gamma rays from the evaporator solutions during operation. Pulse height analysis of each spectrum gives the information required to deduce the concentration of uranium in the evaporator solution in near-real time. The visual readout of concentration is updated at the end of every assay cycle. The readout includes an alphanumeric display of uranium concentration and an illuminated, colored LED (in an array of colored LEDs) indicating whether the measured concentration is within (or above or below) the desired range. An alphanumeric display of evaporator solution acid molarity is also available to the operator. 9 refs., 16 figs., 4 tabs

  2. Concentration of trace elements in marine organisms

    International Nuclear Information System (INIS)

    Ishii, Takaaki; Suzuki, Hamaji; Iimura, Mitsue; Koyanagi, Taku

    1976-01-01

    Information on the quality and quantity of stable trace elements in marine environments is frequently required to analyze the radioecological behavior of radionuclides released from nuclear facilities into the sea. In the present work, special attention was concentrated in determination of stable Mn, Fe, Co, Zn, Rb and Cs in marine organisms to estimate the concentration factors for these elements and corresponding radionuclides. Marine organisms (fishes, marine invertebrates and seaweeds) were collected at the seashore of Ibaragi prefecture and provided for chemical analysis after dry-ashing and wet-ashing. Atomic absorption spectrophotometry and neutron activation analysis were applied to determine the concentration of elements. The concentration of stable elements in fish muscle was independent on species of the fishes though slightly higher trends were observed in ''Usumebaru'', Sebastes nivosus for Cs, ''Ishimochi'', Nibea mitsukurii for Zn and Fe compared with other species. The concentration of Co, Zn and Fe in muscle of marine invertebrates was one order of magnitude higher than fish muscles especially in shellfishes for Co. Seaweeds showed peculiar species specificity for the concentration of stable trace elements and remarkable differences was observed between the species even among the same genus. (auth.)

  3. Isoflurane minimum alveolar concentration reduction by fentanyl.

    Science.gov (United States)

    McEwan, A I; Smith, C; Dyar, O; Goodman, D; Smith, L R; Glass, P S

    1993-05-01

    Isoflurane is commonly combined with fentanyl during anesthesia. Because of hysteresis between plasma and effect site, bolus administration of fentanyl does not accurately describe the interaction between these drugs. The purpose of this study was to determine the MAC reduction of isoflurane by fentanyl when both drugs had reached steady biophase concentrations. Seventy-seven patients were randomly allocated to receive either no fentanyl or fentanyl at several predetermined plasma concentrations. Fentanyl was administered using a computer-assisted continuous infusion device. Patients were also randomly allocated to receive a predetermined steady state end-tidal concentration of isoflurane. Blood samples for fentanyl concentration were taken at 10 min after initiation of the infusion and before and immediately after skin incision. A minimum of 20 min was allowed between the start of the fentanyl infusion and skin incision. The reduction in the MAC of isoflurane by the measured fentanyl concentration was calculated using a maximum likelihood solution to a logistic regression model. There was an initial steep reduction in the MAC of isoflurane by fentanyl, with 3 ng/ml resulting in a 63% MAC reduction. A ceiling effect was observed with 10 ng/ml providing only a further 19% reduction in MAC. A 50% decrease in MAC was produced by a fentanyl concentration of 1.67 ng/ml. Defining the MAC reduction of isoflurane by all the opioids allows their more rational administration with inhalational anesthetics and provides a comparison of their relative anesthetic potencies.

  4. Fine particle number and mass concentration measurements in urban Indian households.

    Science.gov (United States)

    Mönkkönen, P; Pai, P; Maynard, A; Lehtinen, K E J; Hämeri, K; Rechkemmer, P; Ramachandran, G; Prasad, B; Kulmala, M

    2005-07-15

    Fine particle number concentration (D(p)>10 nm, cm(-3)), mass concentrations (approximation of PM(2.5), microg m(-3)) and indoor/outdoor number concentration ratio (I/O) measurements have been conducted for the first time in 11 urban households in India, 2002. The results indicate remarkable high indoor number and mass concentrations and I/O number concentration ratios caused by cooking. Besides cooking stoves that used liquefied petroleum gas (LPG) or kerosene as the main fuel, high indoor concentrations can be explained by poor ventilation systems. Particle number concentrations of more than 300,000 cm(-3) and mass concentrations of more than 1000 microg m(-3) were detected in some cases. When the number and mass concentrations during cooking times were statistically compared, a correlation coefficient r>0.50 was observed in 63% of the households. Some households used other fuels like wood and dung cakes along with the main fuel, but also other living activities influenced the concentrations. In some areas, outdoor combustion processes had a negative impact on indoor air quality. The maximum concentrations observed in most cases were due to indoor combustion sources. Reduction of exposure risk and health effects caused by poor indoor air in urban Indian households is possible by improving indoor ventilation and reducing penetration of outdoor particles.

  5. Extraction of antimony and arsenic from sulphidic concentrates

    Directory of Open Access Journals (Sweden)

    BalហPeter

    2000-09-01

    Full Text Available The efficiency of both mineral processing and extractive metallurgy of minerals depends on the separation of individual mineral components and on the exposure of their surface. The production of flotation concentrates, with particle sizes of tens of microns, is not sufficient for many hydrometallurgical processes to operate at their optimum. As a consequence, metallurgical plants require for the effective processing high temperatures and pressures and some sort of concentrate pretreatment. Mechanical activation is an innovative procedure where an improvement in hydrometallurgical processes can be attained via a combination of new surface area and formation of crystalline defects in minerals. The lowering of reaction temperatures, the increase of rate and amount of solubility, preparation of water soluble compounds, the necessity for simpler and less expensive reactors and shorter reaction times are some of the advantages of mechanical activation. The environmental aspects of these processes are particularly attractive.This paper is devoted to the examples of application of mechanochemical treatment in the processing of sulfidic concentrates. The sulphide concentrates of various origin (Peru, Chile, Slovakia were succesfully tested for antimony and arsenic extraction. The mechanochemical treatment improve the degree of recovery and the rate of leaching of both metals. Two modes of mechanochemical treatment were tested: the mechanical activation before leaching and the mechanochemical leaching which integrates mechanical activation and leaching into a common step. The flowsheet consisted of mechanochemical leaching in an attritor and further operations as filtration, cementation, antimony precipitation, crystallization and arsenic precipitation. The pilot plant unit was designed for 500 kg per day feed of tetrahedrite concentrate. For the antimony extraction, electrowinning has also been considered. The residue which is a CuAgAu concentrate was

  6. Incineration of ion exchange resins using concentric burners

    International Nuclear Information System (INIS)

    Fukasawa, T.; Chino, K.; Kawamura, F.; Kuriyama, O.; Yusa, H.

    1985-01-01

    A new incineration method, using concentric burners, is studied to reduce the volume of spent ion exchange resins generated from nuclear power plants. Resins are ejected into the center of a propane-oxygen flame and burned within it. The flame length is theoretically evaluated by the diffusion-dominant model. By reforming the burner shape, flame length can be reduced by one-half. The decomposition ratio decreases with larger resin diameters due to the loss of unburned resin from the flame. A flame guide tube is adapted to increase resin holding time in the flame, which improves the decomposition ratio to over 98 wt%

  7. The Iron Removal in Marmatite Concentrate Pressure Leaching Process

    Science.gov (United States)

    Wen-bo, LUO; Ji-kun, WANG; Yin, GAN

    2018-01-01

    To modify the pressure leaching technology of horizontal autoclave using marmatite concentrate, an appropriate increase in the pulp’s residence time in the horizontal autoclave is required. This increase will provide sufficient time for leaching to be completed in the first three chambers of the horizontal autoclave. Adding zinc oxide ore and potassium sulfate in the fourth chamber of the horizontal autoclave is needed to complete preliminary neutralization and iron precipitation in the horizontal autoclave. The pilot plant experimental results of the proposed technology are satisfactory, further shortening the process of pressure leaching and improving its economic efficiency.

  8. Laser metrology in fluid mechanics granulometry, temperature and concentration measurements

    CERN Document Server

    Boutier, Alain

    2013-01-01

    In fluid mechanics, non-intrusive measurements are fundamental in order to improve knowledge of the behavior and main physical phenomena of flows in order to further validate codes.The principles and characteristics of the different techniques available in laser metrology are described in detail in this book.Velocity, temperature and concentration measurements by spectroscopic techniques based on light scattered by molecules are achieved by different techniques: laser-induced fluorescence, coherent anti-Stokes Raman scattering using lasers and parametric sources, and absorption sp

  9. Sensor concentrator unit for the Continuous Automated Vault Inventory System

    International Nuclear Information System (INIS)

    Nodine, R.N.; Lenarduzzi, R.

    1997-06-01

    The purpose of this document is to describe the use and operation of the sensor concentrator in the Continuous Automated Vault Inventory System (CAVIS). The CAVIS electronically verifies the presence of items of stored special nuclear material (SNM). US Department of Energy orders require that stored SNM be inventoried periodically to provide assurance that the material is secure. Currently this inventory is a highly manual activity, requiring personnel to enter the storage vaults. Using a CAVIS allows the frequency of physical inventories to be significantly reduced, resulting in substantial cost savings, increased security, and improved safety. The electronic inventory of stored SNM requires two different types of sensors for each item. The two sensors measure different parameters of the item, usually weight and gamma rays. A CAVIS is constructed using four basic system components: sensors, sensor concentrators, a data collection unit, and a database/user interface unit. One sensor concentrator supports the inventory of up to 20 items (40 sensors) and continuously takes readings from the item sensors. On request the sensor concentrator outputs the most recent sensor readings to the data collection unit. The information transfer takes place over a RS485 communications link. The data collection unit supports from 1 to 120 sensor concentrators (1 to 2,400 items) and is referred to as the Sensor Polling and Configuration System (SPCS). The SPCS is connected by a secure Transmission Control Protocol/Internet Protocol (TCP/IP) network to the database/user interface unit, which is referred to as the Graphical Facility Information Center (GraFIC). A CAVIS containing more than 2,400 items is supported by connecting additional SPCS units to the GraFIC

  10. Sensor concentrator unit for the Continuous Automated Vault Inventory System

    Energy Technology Data Exchange (ETDEWEB)

    Nodine, R.N.; Lenarduzzi, R.

    1997-06-01

    The purpose of this document is to describe the use and operation of the sensor concentrator in the Continuous Automated Vault Inventory System (CAVIS). The CAVIS electronically verifies the presence of items of stored special nuclear material (SNM). US Department of Energy orders require that stored SNM be inventoried periodically to provide assurance that the material is secure. Currently this inventory is a highly manual activity, requiring personnel to enter the storage vaults. Using a CAVIS allows the frequency of physical inventories to be significantly reduced, resulting in substantial cost savings, increased security, and improved safety. The electronic inventory of stored SNM requires two different types of sensors for each item. The two sensors measure different parameters of the item, usually weight and gamma rays. A CAVIS is constructed using four basic system components: sensors, sensor concentrators, a data collection unit, and a database/user interface unit. One sensor concentrator supports the inventory of up to 20 items (40 sensors) and continuously takes readings from the item sensors. On request the sensor concentrator outputs the most recent sensor readings to the data collection unit. The information transfer takes place over a RS485 communications link. The data collection unit supports from 1 to 120 sensor concentrators (1 to 2,400 items) and is referred to as the Sensor Polling and Configuration System (SPCS). The SPCS is connected by a secure Transmission Control Protocol/Internet Protocol (TCP/IP) network to the database/user interface unit, which is referred to as the Graphical Facility Information Center (GraFIC). A CAVIS containing more than 2,400 items is supported by connecting additional SPCS units to the GraFIC.

  11. Radon concentrations in residential housing in hiroshima and nagasaki

    International Nuclear Information System (INIS)

    Aoyama, Takashi; Radford, E.P.; Yonehara, Hidenori; Kato, Hiroo; Sakanoue, Masanobu.

    1993-05-01

    A survey of indoor radon ( 222 Rn) concentrations in Hiroshima and Nagasaki was carried out to assess the range of exposures expected among atomic-bomb survivors. Two hundred dwellings (100 from each city), chiefly of members of the Radiation Effects Research Foundation Life Span Study, were selected for this survey. We used two types of etched-track alpha-particle detectors: a Terradex detector (type SF) and an improved bare-track detector. Comparative measurements showed that although there was an adequate correlation between the values obtained using the two detectors, the geometric mean value for the bare-track detector was 45% lower than that for the Terradex detector. This difference was considered to be due to differences in the calibration methods and in the sensitivities of the detectors to thoron ( 220 Rn). The geometric mean values of the radon concentrations for 193 locations in Hiroshima and 192 locations in Nagasaki measured by Terradex SF detectors were 51.8 Bq/m 3 and 26.5 Bq/m 3 , respectively. The large difference is attributable to the different geological environments of the two cities. Factors correlating with the indoor radon concentrations were also studied. The geometric mean concentration was significantly higher in wooden houses with clay walls than in other types of house. This tendency was especially strong in Hiroshima. The difference between the estimated dose equivalents for exposure to radon decay products in dwellings in Hiroshima and Nagasaki during the last 30 years might amount to 0.8 Sv; however, no statistically significant difference was observed in lung-cancer mortality in the low-dose range in either city. Nevertheless, the indoor radon concentrations estimated in this survey could have a significant influence on the dose-response relationship for atomic-bomb exposure. (author)

  12. Rapid Concentration for Improved Detection of Microbes in ISS Potable Water, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Providing a reliable supply of safe drinking water is a critical requirement for space exploration. Systems that provide recycled, treated water aboard the...

  13. Rapid Concentration for Improved Detection of Microbes in ISS Potable Water, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Providing a reliable supply of safe drinking water is a critical requirement for space exploration. Systems that provide recycled treated water aboard the...

  14. Functional vegetable guar (Cyamopsis tetragonoloba L. Taub.) accessions for improving flavonoid concentrations in immature pods

    Science.gov (United States)

    Dry guar (Cyamopsis tetragonoloba L. Taub) seed are primarily used to extract galactomannan gum for oil fracking, however the immature pods are used as a vegetable in India and sold in ethnic grocery stores in the Atlanta, GA area. Twenty-two guar genotypes were grown in the field at Griffin, GA, US...

  15. Preovulatory progesterone concentration associates significantly to follicle number and LH concentration but not to pregnancy rate

    DEFF Research Database (Denmark)

    Yding Andersen, Claus; Bungum, Leif; Nyboe Andersen, Anders

    2011-01-01

    Using data from a large prospective randomized controlled trial that evaluated the effect of recombinant LH (rLH)co-administration for ovarian stimulation, the present study assessed whether progesterone concentration on the day of human chorionic gonadotrophin (HCG) administration was associated...... with or without rLH administration from day 6 of stimulation. There was no significant association between the late-follicular-phase progesterone concentration and the clinical pregnancy rate. However, progesterone concentration was strongly associated with the number of follicles and retrieved oocytes. Late......-follicular-phase LH concentration also showed a significant positive association with progesterone concentration (P = 0.018). Administration of rLH during ovarian stimulation did not affect progesterone concentration. The present study does not support an association between progesterone concentration on the day...

  16. False positive acetaminophen concentrations in icteric serum

    Directory of Open Access Journals (Sweden)

    L. de Jong

    2016-04-01

    Full Text Available Introduction: Serum concentrations of acetaminophen are measured to predict the risk of hepatotoxicity in cases of acetaminophen overdose and to identify acetaminophen use in patients with acute liver injury without a known cause. The acetaminophen concentration determines if treatment with N-acetyl cysteine, the antidote for acetaminophen poisoning, is warranted. Description: A 49-year-old woman was admitted to our hospital with a hepatic encephalopathy and a total serum bilirubin concentration of 442 µmol/l. The acetaminophen concentration of 11.5 mg/l was measured with an enzymatic-colorimetric assay, thus treatment with N-acetyl cysteine was started. Interestingly, the acetaminophen concentration remained unchanged (11.5–12.3 mg/l during a period of 4 consecutive days. In contrast, the acetaminophen concentration measured by HPLC, a chromatographic technique, remained undetectable Discussion: In the presented case, elevated bilirubin was the most likely candidate to interfere with acetaminophen assay causing false positive results. Bilirubin has intense absorbance in the ultraviolet and visible regions of the electromagnetic spectrum and for that reason it causes interference in an enzymatic-colorimetric assay. Conclusion: False positive acetaminophen laboratory test results may be found in icteric serum, when enzymatic-colorimetric assays are used for determination of an acetaminophen concentration. Questionable acetaminophen results in icteric serum should be confirmed by a non-enzymatic method, by means of ultrafiltration of the serum, or by dilution studies. Keywords: Acetaminophen, Enzymatic-colorimetric assays, HPLC, Bilirubin, Interference, Paracetamol, Liver failure, Jaundice

  17. Nonimaging polygonal mirrors achieving uniform irradiance distributions on concentrating photovoltaic cells.

    Science.gov (United States)

    Schmitz, Max; Dähler, Fabian; Elvinger, François; Pedretti, Andrea; Steinfeld, Aldo

    2017-04-10

    We introduce a design methodology for nonimaging, single-reflection mirrors with polygonal inlet apertures that generate a uniform irradiance distribution on a polygonal outlet aperture, enabling a multitude of applications within the domain of concentrated photovoltaics. Notably, we present single-mirror concentrators of square and hexagonal perimeter that achieve very high irradiance uniformity on a square receiver at concentrations ranging from 100 to 1000 suns. These optical designs can be assembled in compound concentrators with maximized active area fraction by leveraging tessellation. More advanced multi-mirror concentrators, where each mirror individually illuminates the whole area of the receiver, allow for improved performance while permitting greater flexibility for the concentrator shape and robustness against partial shading of the inlet aperture.

  18. Can We Manage Nonpoint-Source Pollution Using Nutrient Concentrations during Seasonal Baseflow?

    Directory of Open Access Journals (Sweden)

    James A. McCarty

    2016-05-01

    Full Text Available Nationwide, a substantial amount of resources has been targeted toward improving water quality, particularly focused on nonpoint-source pollution. This study was conducted to evaluate the relationship between nutrient concentrations observed during baseflow and runoff conditions from 56 sites across five watersheds in Arkansas. Baseflow and stormflow concentrations for each site were summarized using geometric mean and then evaluated for directional association. A significant, positive correlation was found for NO–N, total N, soluble reactive P, and total P, indicating that sites with high baseflow concentrations also had elevated runoff concentrations. Those landscape factors that influence nutrient concentrations in streams also likely result in increased runoff, suggesting that high baseflow concentrations may reflect elevated loads from the watershed. The results highlight that it may be possible to collect water-quality data during baseflow to help define where to target nonpoint-source pollution best management practices within a watershed.

  19. Stress concentrations in keyways and optimization of keyway design

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    2010-01-01

    Keys and keyways are one of the most common shaft–hub connections. Despite this fact very little numerical analysis has been reported. The design is often regulated by standards that are almost half a century old, and most results reported in the literature are based on experimental photoelastic...... analysis. The present paper shows how numerical finite element (FE) analysis can improve the prediction of stress concentration in the keyway. Using shape optimization and the simple super elliptical shape, it is shown that the fatigue life of a keyway can be greatly improved with up to a 50 per cent...... reduction in the maximum stress level. The design changes are simple and therefore practical to realize with only two active design parameters....

  20. CDBG Public Improvements Activity

    Data.gov (United States)

    Department of Housing and Urban Development — CDBG activity related to public improvements, including senior centers, youth centers, parks, street improvements, water/sewer improvements, child care centers, fire...