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Sample records for ad lib feeding

  1. Effects of Experimental Negative Affect Manipulations on Ad Lib Smoking: A Meta-Analysis

    PubMed Central

    Heckman, Bryan W.; Carpenter, Mathew J.; Correa, John B.; Wray, Jennifer M.; Saladin, Michael E.; Froeliger, Brett; Drobes, David J.; Brandon, Thomas H.

    2015-01-01

    Aims To quantify the effect of negative affect (NA), when manipulated experimentally, upon smoking as measured within laboratory paradigms. Quantitative meta-analyses tested the effects of NA vs. neutral conditions on 1) latency to smoke and 2) number of puffs taken. Methods Twelve experimental studies tested the influence of NA induction, relative to a neutral control condition (N = 1,190; range = 24–235). Those providing relevant data contributed to separate random effects meta-analyses to examine the effects of NA on two primary smoking measures: 1) latency to smoke (nine studies) and 2) number of puffs taken during ad lib smoking (eleven studies). Hedge’s g was calculated for all studies through the use of post-NA cue responses relative to post-neutral cue responses. This effect size estimate is similar to Cohen’s d, but corrects for small sample size bias. Results NA reliably decreased latency to smoke (g = −.14; CI = −.23 to −.04; p = .007) and increased number of puffs taken (g = .14; CI = .02 to .25; p = .02). There was considerable variability across studies for both outcomes (I2 = 51% and 65% for latency and consumption, respectively). Potential publication bias was indicated for both outcomes, and adjusted effect sizes were smaller and no longer statistically significant. Conclusions In experimental laboratory studies of smokers, negative affect appears to reduce latency to smoking and increase number of puffs taken but this could be due to publication bias. PMID:25641624

  2. Relations between passage rates of rumen fluid and particulate matter and foam production in rumen contents of cattle fed on different diets ad lib.

    PubMed

    Okine, E K; Mathison, G W; Hardin, R T

    1989-03-01

    1. A group of six cattle, three of which had a non-bloating history (group A) and had been ruminally cannulated for the previous 2 years, and three with a history of being bloat-prone (group B) and which had been ruminally cannulated only 3 months before the study, were fed ad lib. on chopped lucerne (Medicago sativa) hay, lucerne pellets, or a 100 g chopped hay and 900 g rolled barley grain/kg diet over three periods of 30 d each. Flow of rumen digesta, by reference to CoEDTA and chromium-mordanted fibres, and foam production from samples of rumen contents were measured. 2. Samples of rumen contents (50 ml) from group A produced foam heights of 150 and 60 mm, 2 and 4 h after feeding respectively, compared with 240 and 150 mm for group B (P less than 0.05). 3. The fractional passage rate of the 1-2 mm particles mordanted with Cr did not differ (P greater than 0.05) between groups. 4. The fractional outflow rates (FOR) for CoEDTA 0-2 h and 2-7 h after feed was offered were 0.205 and 0.160/h for group A and 0.093 and 0.086/h for group B respectively (P less than 0.05). 5. Rumen-fluid FOR 0-2 h and 2-7 h after provision of feed were significantly (P less than 0.05) inversely correlated (r -0.74 and -0.85 respectively) with the amount of foam produced from rumen contents at these times. PMID:2706234

  3. Randomised comparison of diets for maintaining obese subjects' weight after major weight loss: ad lib, low fat, high carbohydrate diet v fixed energy intake.

    PubMed Central

    Toubro, S.; Astrup, A.

    1997-01-01

    OBJECTIVES: To compare importance of rate of initial weight loss for long term outcome in obese patients and to compare efficacy of two different weight maintenance programmes. DESIGN: Subjects were randomised to either rapid or slow initial weight loss. Completing patients were re-randomised to one year weight maintenance programme of ad lib diet or fixed energy intake diet. Patients were followed up one year later. SETTING: University research department in Copenhagen, Denmark. SUBJECTS: 43 (41 women) obese adults (body mass index 27-40) who were otherwise healthy living in or around Copenhagen. INTERVENTIONS: 8 weeks of low energy diet (2 MJ/day) or 17 weeks of conventional diet (5 MJ/day), both supported by an anorectic compound (ephedrine 20 mg and caffeine 200 mg thrice daily); one year weight maintenance programme of ad lib, low fat, high carbohydrate diet or fixed energy intake diet (< or = 7.8 MJ/day), both with reinforcement sessions 2-3 times monthly. MAIN OUTCOME MEASURES: Mean initial weight loss and proportion of patients maintaining a weight loss of > 5 kg at follow up. RESULTS: Mean initial weight loss was 12.6 kg (95% confidence interval 10.9 to 14.3 kg) in rapid weight loss group and 12.6 (9.9 to 15.3) kg in conventional diet group. Rate of initial weight loss had no effect on weight maintenance after 6 or 12 months of weight maintenance or at follow up. After weight maintenance programme, the ad lib group had maintained 13.2 (8.1 to 18.3) kg of the initial weight loss of 13.5 (11.4 to 15.5) kg, and the fixed energy intake group had maintained 9.7 (6.1 to 13.3) kg of the initial 13.8 (11.8 to 15.7) kg weight loss (group difference 3.5 (-2.4 to 9.3) kg). Regained weight at follow up was greater in fixed energy intake group than in ad lib group (11.3 (7.1 to 15.5) kg v 5.4 (2.3 to 8.6) kg, group difference 5.9 (0.7 to 11.1) kg, P < 0.03). At follow up, 65% of ad lib group and 40% of fixed energy intake group had maintained a weight loss of > 5 kg (P

  4. 21 CFR 582.80 - Trace minerals added to animal feeds.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Trace minerals added to animal feeds. 582.80 Section 582.80 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Provisions § 582.80 Trace minerals added to animal feeds. These substances added to animal feeds...

  5. 21 CFR 582.80 - Trace minerals added to animal feeds.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Trace minerals added to animal feeds. 582.80 Section 582.80 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Provisions § 582.80 Trace minerals added to animal feeds. These substances added to animal feeds...

  6. 21 CFR 582.80 - Trace minerals added to animal feeds.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Trace minerals added to animal feeds. 582.80 Section 582.80 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Provisions § 582.80 Trace minerals added to animal feeds. These substances added to animal feeds...

  7. 21 CFR 582.80 - Trace minerals added to animal feeds.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Trace minerals added to animal feeds. 582.80 Section 582.80 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Provisions § 582.80 Trace minerals added to animal feeds. These substances added to animal feeds...

  8. 21 CFR 582.80 - Trace minerals added to animal feeds.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Trace minerals added to animal feeds. 582.80 Section 582.80 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Provisions § 582.80 Trace minerals added to animal feeds. These substances added to animal feeds...

  9. Effect of epidermal growth factor (EGF) on (/sup 3/H)TdR incorporation into DNA in ad lib fed and fasted CD2F1 mice

    SciTech Connect

    Scheving, L.A.; Tsai, T.H.; Scheving, L.E.; Hoke, W.S.

    1987-03-01

    The effect of EGF on the incorporation of (/sup 3/H)TdR into DNA (DNA synthesis) was determined in the esophagus, liver, pancreas, and kidney in mice standardized to 12 hours (hr) of light alternating with 12 hr of darkness. A question asked was whether intraperitoneally administered EGF could alter the circadian patterns of DNA synthesis in these organs. The most marked effects of EGF were: an increase in DNA synthesis but only after a specific duration of time after treatment, ranging from 8 to 23 hr, which differed for each tissue, a similarity in the response of the esophagus in both ad lib fed and fasted mice, but not in the response of the liver, where the stimulatory effect of EGF observed in fed mice was dramatically reduced in fasted ones, and an advance in the phasing of the circadian rhythm in DNA synthesis of the esophagus by about 12 hr. In addition, no sex differences in fasted animals were found under the conditions of this study.

  10. MVC Plugin Lib

    SciTech Connect

    Bauer, Travis

    2008-05-20

    Provides a basic collection of utility plugins for use in the MVC Shell or MVC Framework environment. The MVC PluginLib is implemented in C# as a collection of.NET 2.0 frameworks that implement MVC Framework and MVC Shell compatible plugins. Three plugins are provided at this time, with more to be added over time: ApplicationInfoPlugin - provides basic information about the running application IronPythonPlugin - provides an IronPython based interactive shell environment ProgressBarPlugin - provides a basic progress bar implementation

  11. MVC Plugin Lib

    2008-05-20

    Provides a basic collection of utility plugins for use in the MVC Shell or MVC Framework environment. The MVC PluginLib is implemented in C# as a collection of.NET 2.0 frameworks that implement MVC Framework and MVC Shell compatible plugins. Three plugins are provided at this time, with more to be added over time: ApplicationInfoPlugin - provides basic information about the running application IronPythonPlugin - provides an IronPython based interactive shell environment ProgressBarPlugin - provides amore » basic progress bar implementation« less

  12. Metabolomic study of plasma from female mink (Neovison vison) with low and high residual feed intake during restrictive and ad libitum feeding.

    PubMed

    Hedemann, Mette Skou; Damgaard, Birthe Marie

    2012-12-01

    Metabolite profiling may elucidate changes in metabolic pathways under various physiological or nutritional conditions. In the present study two groups of female mink characterised as having a high (16 mink) or low (14 mink) residual feed intake were investigated during restrictive and ad libitum feeding. Blood samples were collected three times during the experimental period; during restrictive feeding, and four days and three weeks after the change to ad libitum feeding. Plasma samples were subjected to liquid chromatography mass spectrometry non-targeted metabolomics. Subjecting data to principal component analysis showed that there was no grouping of the data according to the residual feed intake. In contrast, data were clearly grouped according to feeding level. Identification of the metabolites responsible for this grouping showed that the plasma level of metabolites related to mobilisation of energy was high during restrictive feeding, e.g. betaine, carnitine, and creatine. During ad libitum feeding the plasma level of metabolites that can be characterised as biomarkers of meat intake (creatinine, carnosine, 1- and 3 methylhistidine) was high. The plasma level of lysophosphatidylcholine species was highest after four days of ad libitum feeding suggesting a short term imbalance in the transport or metabolism of these metabolites when changing the feeding level. PMID:23123310

  13. Effects of ad libitum and restricted feeding on early production performance and body composition of Yorkshire pigs selected for reduced residual feed intake.

    PubMed

    Boddicker, N; Gabler, N K; Spurlock, M E; Nettleton, D; Dekkers, J C M

    2011-08-01

    Residual feed intake (RFI), defined as the difference between observed and expected feed intake based on growth and backfat, has been used to investigate genetic variation in feed efficiency in cattle, poultry and pigs. However, little is known about the biological basis of differences in RFI in pigs. To this end, the objective of this study was to evaluate the fifth generation of a line of pigs selected for reduced RFI against a randomly selected Control line for performance, carcass and chemical carcass composition and overall efficiency. Here, emphasis was on the early grower phase. A total of 100 barrows, 50 from each line, were paired by age and weight (22.6 ± 3.9 kg) and randomly assigned to one of four feeding treatments in 11 replicates: ad libitum (Ad), 75% of Ad (Ad75), 55% of Ad (Ad55) and weight stasis (WS), which involved weekly adjustments in intake to keep body weight (BW) constant for each pig. Pigs were individually penned (group housing was used for selection) and were on treatment for 6 weeks. Initial BW did not significantly differ between the lines (P > 0.17). Under Ad feeding, the low RFI pigs consumed 8% less feed compared with Control line pigs (P < 0.06), had less carcass fat (P < 0.05), but with no significant difference in growth rate (P > 0.85). Under restricted feeding, low RFI pigs under the Ad75 treatment had a greater rate of gain while consuming the same amount of feed as Control pigs. Despite the greater gain, no significant line differences in carcass composition or carcass traits were observed. For the WS treatment, low RFI pigs had similar BW (P > 0.37) with no significant difference in feed consumption (P > 0.32). Overall, selection for reduced RFI has decreased feed intake, with limited differences in growth rate but reduced carcass fat, as seen under Ad feeding. Collectively, results indicate that the effects of selection for low RFI are evident during the early grower stage, which allows for greater savings to the producer

  14. Direct and correlated responses to selection in two lines of rabbits selected for feed efficiency under ad libitum and restricted feeding: I. Production traits and gut microbiota characteristics.

    PubMed

    Drouilhet, L; Achard, C S; Zemb, O; Molette, C; Gidenne, T; Larzul, C; Ruesche, J; Tircazes, A; Segura, M; Bouchez, T; Theau-Clément, M; Joly, T; Balmisse, E; Garreau, H; Gilbert, H

    2016-01-01

    To get insights into selection criteria for feed efficiency, 2 rabbit lines have been created: the ConsoResidual line was selected for residual feed intake (RFI) with ad libitum feeding and the ADGrestrict line was selected for ADG under restricted feeding (-20% of voluntary intake). The first objective of this study was to evaluate, after 9 generations of selection, the direct and correlated responses to selection on production traits in the 2 lines for traits recorded during growth. Second, applying the 2 feeding conditions used for selection to both selected lines plus the control unselected line (generation 0, G0) in a 2 × 3 factorial trial, the line performances were compared and the gut microbiota of the lines was characterized. The correlated responses in feed conversion ratio (FCR) were remarkably equivalent in both selected lines (-2.74 genetic σ) but correlated responses in other traits were notably different. In the ConsoResidual line, selection for decreased RFI resulted in a small negative correlated response in BW at 63 d old (BW63) and in a null response in ADG. In the ADGrestrict line, on the contrary, the correlated response in BW63 was substantial (+1.59 σ). The 2 selected lines had a FCR reduced by 0.2 point compared with the G0 line, and the same difference was found in both feeding regimens ( < 0.001). Indeed, selection on ADG would lead to heavier animals with no significant reduction of feed costs, whereas selection on RFI leads to lower feed costs and no increase of animal BW under ad libitum feeding. Altogether, our results do not suggest any genotype × environment interaction in the response to feeding regimens. The intestinal microbial communities from efficient rabbits differed from their unselected counterparts in terms of fermentation end products and microbial phylotypes, suggesting a central role of these microbes in the better feed efficiency of the rabbits. PMID:26812310

  15. Time-restricted feeding reduces adiposity in mice fed a high-fat diet.

    PubMed

    Sundaram, Sneha; Yan, Lin

    2016-06-01

    Disruption of the circadian rhythm contributes to obesity. This study tested the hypothesis that time-restricted feeding (TRF) reduces high-fat diet-induced increase in adiposity. Male C57BL/6 mice were fed the AIN93G or the high-fat diet ad libitum (ad lib); TRF of the high-fat diet for 12 or 8hours during the dark cycle was initiated when high-fat diet-fed mice exhibited significant increases in body weight. Energy intake of the TRF 12-hour group was not different from that of the high-fat ad lib group, although that of the TRF 8-hour group was slightly but significantly lower. Restricted feeding of the high-fat diet reduced body fat mass and body weight compared with mice fed the high-fat diet ad lib. There were no differences in respiratory exchange ratio (RER) among TRF and high-fat ad lib groups, but the RER of these groups was lower than that of the AIN93G group. Energy expenditure of the TRF groups was slightly but significantly lower than that of the high-fat ad lib group. Plasma concentrations of ghrelin were increased in TRF groups compared with both AIN93G and high-fat ad lib groups. Elevations of plasma concentrations of insulin, leptin, monocyte chemoattractant protein-1, and tissue inhibitor metalloproteinase-1 by high-fat ad lib feeding were reduced by TRF to the levels of mice fed the AIN93G diet. In conclusion, TRF during the dark cycle reduces high-fat diet-induced increases in adiposity and proinflammatory cytokines. These results indicate that circadian timing of food intake may prevent obesity and abate obesity-related metabolic disturbance. PMID:27188906

  16. Ad libitum feeding following ovariectomy in female Beagle dogs: effect on maintenance energy requirement and on blood metabolites.

    PubMed

    Jeusette, I; Detilleux, J; Cuvelier, C; Istasse, L; Diez, M

    2004-04-01

    The aim of this study was (i) to evaluate the effect of ovariectomy on daily energy requirement in Beagle dogs, and (ii) to evaluate the effects of ad libitum feeding with a high energy diet on energy consumption, body weight gain and blood metabolites in these spayed dogs. Four young adult female Beagle dogs were used. Ovariectomy induced a significant decrease of daily energy requirement in dogs. Ad libitum feeding, initiated 6 months after spaying, induced a significant increase in consumption in spayed dogs. This overconsumption was greatest during the first month of ad libitum feeding but continued for the entire 4 months of this period. When fed ad libitum, dogs gained excess body weight without significant effect on plasma cholesterol, triglycerides, glucose and insulin, at short term. These data suggest that energy intake should be strictly controlled to avoid excess weight gain in spayed dogs. PMID:15059235

  17. A return to ad libitum feeding following caloric restriction promotes hepatic steatosis in hyperphagic OLETF rats.

    PubMed

    Linden, Melissa A; Fletcher, Justin A; Meers, Grace M; Thyfault, John P; Laughlin, M Harold; Rector, R Scott

    2016-09-01

    Hyperphagic Otsuka Long-Evans Tokushima fatty (OLETF) rats develop obesity, insulin resistance, and nonalcoholic fatty liver disease (NAFLD), but lifestyle modifications, such as caloric restriction (CR), can prevent these conditions. We sought to determine if prior CR had protective effects on metabolic health and NAFLD development following a 4-wk return to ad libitum (AL) feeding. Four-week-old male OLETF rats (n = 8-10/group) were fed AL for 16 wk (O-AL), CR for 16 wk (O-CR; ∼70% kcal of O-AL), or CR for 12 wk followed by 4 wk of AL feeding (O-AL4wk). CR-induced benefit in prevention of NAFLD, including reduced hepatic steatosis, inflammation, and markers of Kupffer cell activation/number, was largely lost in AL4wk rats. These findings occurred in conjunction with a partial loss of CR-induced beneficial effects on obesity and serum triglycerides in O-AL4wk rats, but in the absence of changes in serum glucose or insulin. CR-induced increases in hepatic mitochondrial respiration remained significantly elevated (P < 0.01) in O-AL4wk compared with O-AL rats, while mitochondrial [1-(14)C]palmitate oxidation, citrate synthase activity, and β-hydroxyacyl-CoA dehydrogenase activity did not differ among OLETF groups. NAFLD development in O-AL4wk rats was accompanied by increases in the protein content of the de novo lipogenesis markers fatty acid synthase and stearoyl-CoA desaturase-1 and decreases in phosphorylated acetyl-CoA carboxylase (pACC)/ACC compared with O-CR rats (P < 0.05 for each). The beneficial effects of chronic CR on NAFLD development were largely lost with 4 wk of AL feeding in the hyperphagic OLETF rat, highlighting the importance of maintaining energy balance in the prevention of NAFLD. PMID:27445343

  18. Attraction, Feeding, and Control of Rhagoletis pomonella (Diptera: Tephritidae) Using GF-120 with Added Ammonia in Washington

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted in 2005 and 2006 in western Washington State to determine effects of adding ammonium carbonate (AC) and ammonium acetate (AA) to GF-120 Fruit Fly Bait (Dow AgroSciences, Indianapolis, IN) on attraction, feeding, and control of the apple maggot fly, Rhagoletis pomonella (Wa...

  19. Direct and correlated responses to selection in two lines of rabbits selected for feed efficiency under ad libitum and restricted feeding: II. Carcass and meat quality.

    PubMed

    Molette, C; Gilbert, H; Larzul, C; Balmisse, E; Ruesche, J; Manse, H; Tircazes, A; Theau-Clément, M; Joly, T; Gidenne, T; Garreau, H; Drouilhet, L

    2016-01-01

    To get insights into selection criteria for feed efficiency, 2 rabbit lines have been created: the ConsoResidual line was selected for residual feed intake (RFI) with ad libitum feeding and the ADGrestrict line was selected for ADG under restricted feeding. The aim of the present study was to evaluate the impact on carcass and meat quality of the genetic selections. This comparison was performed using 2 different feeding strategies corresponding to the selection design. Carcass and meat quality traits were recorded for the 3 lines (ConsoResidual, ADGrestrict, and an unselected control [generation 0 {G0}]) in the 2 feeding systems (ad libitum and restricted) for 163 animals. Concerning the line effect, the BW at 63 d old was higher for the ADGrestrict line compared with the G0 and ConsoResidual lines ( < 0.0001). There was no line effect on the gastrointestinal tract. The rabbits did not exhibit a different carcass yield but showed different carcass traits. Indeed, the ConsoResidual rabbits had a higher hind leg yield ( < 0.0001) but no difference in the meat-to-bone ratio of the hind leg. On the contrary, the ADGrestrict line had a higher proportion of forelegs plus thoracic cage ( = 0.03). We also found lower perirenal ( < 0.0001) and scapular fat yields ( < 0.0001) in ConsoResidual rabbits. The ADGrestrict line had an intermediate perirenal fat yield compared with the other 2 lines. The G0 line always exhibited higher fat yields. Concerning meat quality, the ConsoResidual rabbits showed a lower ultimate pH ( < 0.0001) and higher water loss (drip and cooking loss; < 0.002) compared with the G0 and ADGrestrict rabbits. The feeding level had a strong effect on the gastrointestinal tract ( = 0.0004) and the carcass yield ( = 0.001). The latter was decreased in restricted rabbits. The effects of feeding strategy on meat quality were detrimental in the case of restricted feeding. Even if the ultimate pH was slightly higher in restricted rabbits ( = 0.0002), the carcass

  20. Effects of alginate and resistant starch on feeding patterns, behaviour and performance in ad libitum-fed growing pigs.

    PubMed

    Souza da Silva, C; Bosch, G; Bolhuis, J E; Stappers, L J N; van Hees, H M J; Gerrits, W J J; Kemp, B

    2014-12-01

    This study assessed the long-term effects of feeding diets containing either a gelling fibre (alginate (ALG)), or a fermentable fibre (resistant starch (RS)), or both, on feeding patterns, behaviour and growth performance of growing pigs fed ad libitum for 12 weeks. The experiment was set up as a 2×2 factorial arrangement: inclusion of ALG (yes or no) and inclusion of RS (yes or no) in the control diet, resulting in four dietary treatments, that is, ALG-RS- (control), ALG+RS-, ALG-RS+, and ALG+RS+. Both ALG and RS were exchanged for pregelatinized potato starch. A total of 240 pigs in 40 pens were used. From all visits to an electronic feeding station, feed intake and detailed feeding patterns were calculated. Apparent total tract digestibility of energy, dry matter (DM), and CP was determined in week 6. Pigs' postures and behaviours were scored from live observations in weeks 7 and 12. Dietary treatments did not affect final BW and average daily gain (ADG). ALG reduced energy and DM digestibility (P<0.01). Moreover, ALG increased average daily DM intake, and reduced backfat thickness and carcass gain : digestible energy (DE) intake (P<0.05). RS increased feed intake per meal, meal duration (P<0.05) and inter-meal intervals (P=0.05), and reduced the number of meals per day (P<0.01), but did not affect daily DM intake. Moreover, RS reduced energy, DM and CP digestibility (P<0.01). Average daily DE intake was reduced (P<0.05), and gain : DE intake tended to be increased (P=0.07), whereas carcass gain : DE intake was not affected by RS. In week 12, ALG+RS- increased standing and walking, aggressive, feeder-directed, and drinking behaviours compared with ALG+RS+ (ALG×RS interaction, P<0.05), with ALG-RS- and ALG-RS+ in between. No other ALG×RS interactions were found. In conclusion, pigs fed ALG compensated for the reduced dietary DE content by increasing their feed intake, achieving similar DE intake and ADG as control pigs. Backfat thickness and carcass efficiency

  1. Wheel-running reinforcement in free-feeding and food-deprived rats.

    PubMed

    Belke, Terry W; Pierce, W David

    2016-03-01

    Rats experiencing sessions of 30min free access to wheel running were assigned to ad-lib and food-deprived groups, and given additional sessions of free wheel activity. Subsequently, both ad-lib and deprived rats lever pressed for 60s of wheel running on fixed ratio (FR) 1, variable ratio (VR) 3, VR 5, and VR 10 schedules, and on a response-initiated variable interval (VI) 30s schedule. Finally, the ad-lib rats were switched to food deprivation and the food-deprived rats were switched to free food, as rats continued responding on the response-initiated VI 30-s schedule. Wheel running functioned as reinforcement for both ad-lib and food-deprived rats. Food-deprived rats, however, ran faster and had higher overall lever-pressing rates than free-feeding rats. On the VR schedules, wheel-running rates positively correlated with local and overall lever pressing rates for deprived, but not ad-lib rats. On the response-initiated VI 30s schedule, wheel-running rates and lever-pressing rates changed for ad-lib rats switched to food deprivation, but not for food-deprived rats switched to free-feeding. The overall pattern of results suggested different sources of control for wheel running: intrinsic motivation, contingencies of automatic reinforcement, and food-restricted wheel running. An implication is that generalizations about operant responding for wheel running in food-deprived rats may not extend to wheel running and operant responding of free-feeding animals. PMID:26631601

  2. PV_LIB Toolbox

    2012-09-11

    While an organized source of reference information on PV performance modeling is certainly valuable, there is nothing to match the availability of actual examples of modeling algorithms being used in practice. To meet this need, Sandia has developed a PV performance modeling toolbox (PV_LIB) for Matlab. It contains a set of well-documented, open source functions and example scripts showing the functions being used in practical examples. This toolbox is meant to help make the multi-stepmore » process of modeling a PV system more transparent and provide the means for model users to validate and understand the models they use and or develop. It is fully integrated into Matlab’s help and documentation utilities. The PV_LIB Toolbox provides more than 30 functions that are sorted into four categories« less

  3. PV_LIB Toolbox

    SciTech Connect

    2012-09-11

    While an organized source of reference information on PV performance modeling is certainly valuable, there is nothing to match the availability of actual examples of modeling algorithms being used in practice. To meet this need, Sandia has developed a PV performance modeling toolbox (PV_LIB) for Matlab. It contains a set of well-documented, open source functions and example scripts showing the functions being used in practical examples. This toolbox is meant to help make the multi-step process of modeling a PV system more transparent and provide the means for model users to validate and understand the models they use and or develop. It is fully integrated into Matlab’s help and documentation utilities. The PV_LIB Toolbox provides more than 30 functions that are sorted into four categories

  4. LIBS Analysis for Coal

    NASA Astrophysics Data System (ADS)

    E. Romero, Carlos; De Saro, Robert

    Coal is a non-uniform material with large inherent variability in composition, and other important properties, such as calorific value and ash fusion temperature. This quality variability is very important when coal is used as fuel in steam generators, since it affects boiler operation and control, maintenance and availability, and the extent and treatment of environmental pollution associated with coal combustion. On-line/in situ monitoring of coal before is fed into a boiler is a necessity. A very few analytical techniques like X-ray fluorescence and prompt gamma neutron activation analysis are available commercially with enough speed and sophistication of data collection for continuous coal monitoring. However, there is still a need for a better on-line/in situ technique that has higher selectivity, sensitivity, accuracy and precision, and that is safer and has a lower installation and operating costs than the other options. Laser induced breakdown spectroscopy (LIBS) is ideal for coal monitoring in boiler applications as it need no sample preparation, it is accurate and precise it is fast, and it can detect all of the elements of concern to the coal-fired boiler industry. LIBS data can also be adapted with advanced data processing techniques to provide real-time information required by boiler operators nowadays. This chapter summarizes development of LIBS for on-line/in situ coal applications in utility boilers.

  5. Fattening Holstein heifers by feeding high-moisture corn (whole or ground) ad libitum separately from concentrate and straw.

    PubMed

    Devant, M; Quintana, B; Aris, A; Bach, A

    2015-10-01

    The objectives of this study were to evaluate the effects of high-moisture corn (HMC), either whole or ground, fed separately from concentrate and straw on feeding behavior, rumen fermentation, whole tract digestibility, and nitrogen balance. Twenty-four Holstein heifers (199 ± 5.5 kg BW and 157 ± 6.9 d age) housed in individual pens were assigned to 3 treatments: 1) whole (unprocessed) HMC fed along with concentrate and barley straw, all fed separately and ad libitum (WHMC); 2) HMC ground through a 0.4-cm screen before ensiling and fed along with concentrate and barley straw, all fed separately and ad libitum (GHMC); and 3) a concentrate composed of mainly corn meal, ground through a roller mill with screen openings of 6 mm, and barley straw, both fed separately and ad libitum (Control). Concentrate, HMC, and straw were offered separately ad libitum in a free-choice situation and consumption was recorded daily and BW was recorded weekly. Apparent nutrient digestibility and N balance were determined at the beginning, middle, and end of the study. At the same time points, rumen fluid was collected through rumenocentesis to determine rumen pH and VFA concentrations. Feeding behavior was monitored throughout the study. Animals were harvested after 134 d and HCW, rumen and cecum wall lesions, and liver abscesses were recorded. Treatment did not affect total DMI, feed efficiency, ADG, final BW, and carcass weight or classification. Concentrate consumption (6.6 ± 0.35 kg/d) of Control heifers was greater ( < 0.001) than that of GHMC (4.1 ± 0.35 kg/d) and WHMC heifers (2.8 ± 0.35 kg/d), and GHMC heifers consumed less ( < 0.001) HMC than WHMC heifers (2.3 ± 0.31 and 4.2 ± 0.31 kg/d, respectively). Dietary treatments did not affect rumination, self-grooming, nonnutritive oral behaviors, and rumen pH. However, rumen acetate to propionate ratio decreased when heifers received HMC (1.77 ± 0.276) compared with when heifers received the Control (2.82 ± 0.276). Total

  6. Cultural Heritage Applications of LIBS

    NASA Astrophysics Data System (ADS)

    Anglos, Demetrios; Detalle, Vincent

    A versatile spectrochemical technique enabling nearly instant, multi-element analysis of materials, LIBS is increasingly employed in studies of archaeological and historical objects, monuments and works of art. The development of several mobile LIBS instruments opens a lot more possibilities for analytical campaigns on site: at museums, conservation laboratories and even outdoors at excavation sites or historical monuments. The basic concepts underlying the use of LIBS in the context of cultural heritage studies are briefly reviewed along with technical and instrumentation aspects. Selected examples of analytical studies are discussed with emphasis on cases that demonstrate the use of mobile LIBS instruments.

  7. Feeding the Preschool Child: Documents Issued by PAG Ad Hoc Working Group Meetings (1969-1975).

    ERIC Educational Resources Information Center

    United Nations Industrial Development Organization, Vienna (Austria).

    This document contains six papers prepared between 1969 and 1975 by the Protein-Calorie Advisory Group (PAG) of the United Nations on topics related to the feeding of preschool children in underdeveloped countries. Among the topics covered: (1) nutrition in utero; (2) nutritional aspects of breastfeeding; (3) infant mortality rates as indicators…

  8. Identification and semiquantitative estimation of antibiotics added to complete feeds, premixes, and concentrates.

    PubMed

    Gafner, J L

    1999-01-01

    Classical microbiological methods for determining antimicrobial compounds in feeds are nonspecific. Thus, there is a need to identify biological activity, and bioautography is used for this purpose. A routine method for detecting the following antimicrobial substances in feeds is described: avilamycin, avoparcin, Zn-bacitracin, erythromycin, flavomycin, furazolidone, lasalocid, monensin, narasin, penicillin, salinomycin, spiramycin, tetracyclines, tylosin, and virginiamycin. Carbadox can be detected by UV light examination of the plates prior to bioautography. Semiquantitative estimations of antibiotic content are compared with quantitative determinations of the above mentioned substances in feeds, except erythromycin, penicillin, and tetracyclines. Detection limits range from 0.1 mg/kg (chlortetracycline) to 20 mg/kg (lasalocid). The method involves agar diffusion of buffered samples, a neutral extraction of polyether antibiotics followed by thin-layer chromatography (TLC), and an acid extraction for other antibiotics followed by TLC. Five test bacteria were used for the main detection by agar diffusion: Micrococcus luteus ATCC 9341, Staphylococcus aureus ATCC 6538P, Corynebacterium xerosis NCTC 9755, Bacillus cereus ATCC 11778, and B. subtilis ATCC 6633. Identification after TLC was achieved by bioautography with the most sensitive microorganism(s). This method allows one laboratory technician to analyze up to 30 feed samples within 2.5 working days, provided that feeds of the same category are analyzed in the same run, and that labels of additives are available. Qualitative and semiquantitative information are valuable when performing a quantitative antibiotic determination and it provides proof that the activity determined is due to the tested substance. This last feature is essential from the perspective of quality assurance of results. PMID:10028666

  9. Water reclamation and value-added animal feed from corn-ethanol stillage by fungal processing.

    PubMed

    Rasmussen, M L; Khanal, S K; Pometto, A L; van Leeuwen, J Hans

    2014-01-01

    Rhizopus oligosporus was cultivated on thin stillage from a dry-grind corn ethanol plant. The aim of the research was to develop a process to replace the current energy-intensive flash evaporation and make use of this nutrient-rich stream to create a new co-product in the form of protein-rich biomass. Batch experiments in 5- and 50-L stirred bioreactors showed prolific fungal growth under non-sterile conditions. COD, suspended solids, glycerol, and organic acids removals, critical for in-plant water reuse, reached ca. 80%, 98%, 100% and 100%, respectively, within 5 d of fungal inoculation, enabling effluent recycle as process water. R. oligosporus contains 2% lysine, good levels of other essential amino acids, and 43% crude protein - a highly nutritious livestock feed. Avoiding water evaporation from thin stillage would furthermore save substantial energy inputs on corn ethanol plants. PMID:24269825

  10. The voluntary feed intake of pigs given feeds based on wheat bran, dried citrus pulp and grass meal, in relation to measurements of feed bulk.

    PubMed

    Kyriazakis, I; Emmans, G C

    1995-02-01

    Two experiments were carried out to investigate the capacities of pigs for bulky feeds. In Expt 1 fifteen pigs were offered, from 12 to 25 kg live weight, ad lib. access to one of five feeds which were made by progressively diluting a high-quality feed with wheat bran. Intake initially increased, and then declined, as the proportion of wheat bran was increased. The pigs became better able to accommodate to the more bulky feeds over time. In Expt 2 thirty-six pigs, initially of 12 kg live weight, were used. The feeds were the same high-quality basal feed as in Expt 1 and three others made almost entirely of either wheat bran, dried grass or dried citrus pulp, respectively. The equal-parts mixtures of each of these three bulky feeds with the basal feed were also made to give three series of feeds each comprising the basal, the mixture and the bulky feed. The three feeds in each series were given ad lib. to twelve pigs in a design of two replicated Latin squares with three time-periods. Within each series, and across periods, the intakes of the feeds that were limiting intake were directly proportional to live weight and so a scaled intake, expressed as g/kg live weight per d, was calculated. Across the six limiting feeds, scaled intakes in the final 5 d of each period, when the pigs were in equilibrium with their feeds, were directly proportional to the reciprocal of the water-holding capacities (WHC) of the feeds, as measured by a centrifugation method. There were large effects of feed changes on intake, in the short term, with previous experience of a bulky feed leading to higher intakes of another bulky feed. The intake of the basal feed was not affected by the feed given previously. It was concluded that: (a) the time of adaptation to bulky feeds needs to be considered when attempting to measure, or predict, the rates of intake on different bulky feeds and, (b) the WHC of the feeds could be an appropriate measurement of 'bulk' responsible for limiting their

  11. Digestive response to restricted feeding in migratory yellow-rumped warblers.

    PubMed

    Lee, Kelly A; Karasov, William H; Caviedes-Vidal, Enrique

    2002-01-01

    Smaller guts and slow initial mass gains at stopover sites have led to the idea that digestive physiology limits refueling rates in migrating birds. We tested the digestive-limitation hypothesis in yellow-rumped warblers using food restriction to simulate infrequent feeding during migration, which may cause a reduction in alimentary tract mass. Restricted birds had small intestine, pancreas, and liver masses 18%-22% lower than ad lib.-fed controls. Total activities of sucrase, maltase, aminopeptidase, and amylase were significantly lower in restricted birds, while those of trypsin and chymotrypsin were not. Only aminopeptidase mass-specific activity was significantly lower in restricted birds. Previously restricted birds were able to feed and digest at a high rate immediately following return to ad lib. feeding. Digestive efficiency did not differ between groups. These results suggest that before migration yellow-rumped warblers have some spare digestive capacity to compensate for declines in their digestive organ masses during migration. PMID:12177834

  12. Comparison of time-restricted and ad libitum self-feeding on the growth, feeding behavior and daily digestive enzyme profiles of Atlantic salmon

    NASA Astrophysics Data System (ADS)

    Shi, Ce; Liu, Ying; Yi, Mengmeng; Zheng, Jimeng; Tian, Huiqin; Du, Yishuai; Li, Xian; Sun, Guoxiang

    2016-07-01

    Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and, hence, better growth performance, the assumption has rarely been tested. This study compares the Effects of time-restricted versus free access self-feeding on the growth, feeding behavior and daily digestive enzyme rhythms of Atlantic salmon (Salmo salar). In an experiment that lasted 6 weeks, fish (109.9 g) were divided into two groups: group 1 had free access to a self-feeder (FA); group 2 received three meals per day (2 h per meal) at dawn, midday and dusk via a time-restricted self-feeder (TR). At the end of the experiment, the fish were sampled every 3 h over a 24-h period. The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase, while FA fish displayed no statistically significant rhythms (P<0.05). Pepsin activity of TR fish also showed a significant daily rhythm (P<0.05) with the acrophase at the second feed and a decrease over the next 12 h. Average daily trypsin, lipase and amylase levels of FA fish were significantly lower than those of TR fish (P<0.01); however, the growth performance of both groups was similar (P>0.05). In conclusion, the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance, with the TR group showing comparatively poor blood glucose regulation.

  13. Underwater inverse LIBS (iLIBS) for marine archaeology

    NASA Astrophysics Data System (ADS)

    Asmus, J.; Magde, M.; Elford, J.; Magde, D.; Parfenov, V.

    2013-05-01

    In recent years there have been enormous advances in nautical archaeology through developments in SONAR technologies as well as in manned and robotic submersible vehicles. The number of sunken vessel discoveries has escalated in many of the seas of the world in response to the widespread application of these and other new tools. Customarily, surviving artifacts within the debris field of a wreck are collected and then moved to laboratories, centers, or institutions for analyses and possible conservation. Frequently, the conservation phase involves chemical treatments to stabilize an artefact to standard temperature, pressure, and humidity instead of an undersea environment. Many of the artefacts encountered at an underwater site are now characterized and restored in-situ in accordance with modern trends in art conservation. Two examples of this trend are exemplified by the resting place of the wreck of the Titanic in the Atlantic and the Cancun Underwater Park in the Caribbean Sea. These two debris fields have been turned into museums for diving visitors. Several research groups have investigated the possibility of adapting the well-established analytical tool Laser Induced Breakdown Spectroscopy (LIBS) to in-situ elemental analyses of underwater cultural, historic, and archaeological artefacts where discovered, rather than as a phase of a salvage operation. As the underwater laser ablation associated with LIBS generates a "snowplough" shockwave within the aqueous matrix, the atomic emission spectrum is usually severely attenuated in escaping from the target. Consequently, probative experiments to date generally invoke a submerged air chamber or air jet to isolate water from the interaction zone as well as employ more complex double-pulse lasers. These measures impose severe logistical constraints on the examination of widely dispersed underwater artefacts. In order to overcome this constraint we report on water-immersion LIBS experiments performed with oblique

  14. CH4 and N2O emissions from China's beef feedlots with ad libitum and restricted feeding in fall and spring seasons.

    PubMed

    Lin, Zhi; Liao, Wenhua; Yang, Yuanyuan; Gao, Zhiling; Ma, Wenqi; Wang, Dianwu; Cao, Yufeng; Li, Jianguo; Cai, Zhenjiang

    2015-04-01

    Accurately quantifying methane (CH4) and nitrous oxide (N2O) emissions from beef operations in China is necessary to evaluate the contribution of beef cattle to greenhouse gas budgets at the national and global level. Methane and N2O emissions from two intensive beef feedlots in the North China Plain, one with a restricted feeding strategy and high manure collection frequency and the other with an ad libitum feeding strategy and low manure collection frequency, were quantified in the fall and spring seasons using an inverse dispersion technique. The diel pattern of CH4 from the beef feedlot with an ad libitum feed strategy (single peak during a day) differed from that under a restricted feeding condition (multiple peaks during a day), but little difference in the diel pattern of N2O emissions between two feeding strategies was observed. The two-season average CH4 emission rates of the two intensive feedlots were 230 and 198gCH4animal(-1)d(-1) and accounted for 6.7% and 6.8% of the gross energy intake, respectively, indicating little impact of the feeding strategy and manure collection frequency on the CH4 conversion factor at the feedlot level. However, the average N2O emission rates (21.2g N2Oanimal(-1)d(-1)) and conversion factor (8.5%) of the feedlot with low manure collection frequency were approximately 131% and 174% greater, respectively, than the feedlot under high frequency conditions, which had a N2O emission rate and conversion factor of 9.2g N2Oanimal(-1)d(-1) and 3.1%, respectively, indicating that increasing manure collection frequency played an important role in reducing N2O emissions from beef feedlots. In addition, comparison indicated that China's beef and dairy cattle in feedlots appeared to have similar CH4 conversion factors. PMID:25769128

  15. Downhole Elemental Analysis with LIBS

    NASA Technical Reports Server (NTRS)

    Moreschini, Paolo; Zacny, Kris; Rickman, Doug

    2011-01-01

    In this paper we discuss a novel instrument, currently under development at Honeybee Robotics with SBIR funding from NASA. The device is designed to characterize elemental composition as a function of depth in non-terrestrial geological formations. The instrument consists of a miniaturized laser-induced breakdown spectrometer (LIBS) analyzer integrated in a 2" diameter drill string. While the drill provides subsurface access, the LIBS analyzer provides information on the elemental composition of the borehole wall. This instrument has a variety of space applications ranging from exploration of the Moon for which it was originally designed, to Mars, as well as a variety of terrestrial applications. Subsurface analysis is usually performed by sample acquisition through a drill or excavator, followed by sample preparation and subsequent sample presentation to an instrument or suite of instruments. An alternative approach consisting in bringing a miniaturized version of the instrument to the sample has many advantages over the traditional methodology, as it allows faster response, reduced probability of cross-contamination and a simplification in the sampling mechanisms. LIBS functions by focusing a high energy laser on a material inducing a plasma consisting of a small fraction of the material under analysis. Optical emission from the plasma, analyzed by a spectrometer, can be used to determine elemental composition. A triangulation sensor located in the sensor head determines the distance of the sensor from the borehole wall. An actuator modifies the position of the sensor accordingly, in order to compensate for changes due to the profile of the borehole walls. This is necessary because LIBS measurements are negatively affected by changes in the relative position of the focus of the laser with respect to the position of the sample (commonly referred to as the "lens to sample distance"). Profiling the borehole is done by adjusting the position of the sensor with a

  16. Downhole elemental analysis with LIBS

    NASA Astrophysics Data System (ADS)

    Moreschini, P.; Zacny, K.; Rickman, D.

    2011-12-01

    In this paper we discuss a novel instrument, currently under development at Honeybee Robotics with SBIR funding from NASA. The device is designed to characterize elemental composition as a function of depth in non-terrestrial geological formations. The instrument consists of a miniaturized LIBS analyzer integrated in a 2" diameter drill string. While the drill provides subsurface access, the LIBS analyzer provides information on the elemental composition of the borehole wall. This instrument has a variety of space applications ranging from exploration of the Moon for which it was originally designed, to Mars, as well as a variety of terrestrial applications. Subsurface analysis is usually performed by sample acquisition through a drill or excavator, followed by sample preparation and subsequent sample presentation to an instrument or suite of instruments. An alternative approach consisting in bringing a miniaturized version of the instrument to the sample has many advantages over the traditional methodology, as it allows faster response, reduced probability of cross-contamination and a simplification in the sampling mechanisms. LIBS functions by focusing a high energy laser on a material inducing a plasma consisting of a small fraction of the material under analysis. Optical emission from the plasma, analyzed by a spectrometer, can be used to determine elemental composition. A triangulation sensor located in the sensor head determines the distance of the sensor from the borehole wall. An actuator modifies the position of the sensor accordingly, in order to compensate for changes due to the profile of the borehole walls. This is necessary because LIBS measurements are negatively affected by changes in the relative position of the focus of the laser with respect to the position of the sample (commonly referred to as the "lens to sample distance"). Profiling the borehole is done by adjusting the position of the sensor with a vertical stage; a second actuator at the

  17. Effect of Atmospheric Conditions on LIBS Spectra

    PubMed Central

    Effenberger, Andrew J.; Scott, Jill R.

    2010-01-01

    Laser-induced breakdown spectroscopy (LIBS) is typically performed at ambient Earth atmospheric conditions. However, interest in LIBS in other atmospheric conditions has increased in recent years, especially for use in space exploration (e.g., Mars and Lunar) or to improve resolution for isotopic signatures. This review focuses on what has been reported about the performance of LIBS in reduced pressure environments as well as in various gases other than air. PMID:22399914

  18. Effect of atmospheric conditions on LIBS spectra.

    PubMed

    Effenberger, Andrew J; Scott, Jill R

    2010-01-01

    Laser-induced breakdown spectroscopy (LIBS) is typically performed at ambient Earth atmospheric conditions. However, interest in LIBS in other atmospheric conditions has increased in recent years, especially for use in space exploration (e.g., Mars and Lunar) or to improve resolution for isotopic signatures. This review focuses on what has been reported about the performance of LIBS in reduced pressure environments as well as in various gases other than air. PMID:22399914

  19. Effect of Atmospheric Conditions on LIBS Spectra

    SciTech Connect

    Andrew J. Effenberger; Jill R. Scott

    2010-05-01

    Laser-induced breakdown spectroscopy (LIBS) is typically performed at ambient Earth atmospheric conditions. However, interest in LIBS in other atmospheric conditions has increased in recent years, especially for use in space exploration (e.g., Mars and Lunar) or to improve resolution for isotopic signatures. This review focuses on what has been reported about the performance of LIBS in reduced pressure environments as well as in various gases other than air.

  20. Reproductive Performance Of Heifers Offered Ad Libitum Or Restricted Access To Feed For A 140-D Period After Weaning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reproductive performance was evaluated in heifers born in 4 years that were randomly assigned to either control (fed to appetite; n = 268) or restricted (fed at 80 % of that consumed by controls adjusted to a common BW basis; n = 263) feeding during a 140-d postweaning trial, beginning about 2 mo af...

  1. Reproductive Performance of Heifers Offered Ad Libitum Or Restricted Access To Feed For A 140-D Period After Weaning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reproductive performance was evaluated in heifers born in 4 years that were randomly assigned to either control (fed to appetite; n = 268) or restricted (fed at 80 % of that consumed by controls adjusted to a common BW basis; n = 263) feeding during a 140-d postweaning trial, beginning about 2 mo af...

  2. Reproductive performance of heifers offered ad libitum or restricted access to feed for a 140-d period after weaning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reproductive performance was evaluated in composite heifers born over a 4-yr period that were randomly assigned to control (fed to appetite; n = 268) or restricted fed at 80 % of that consumed by controls adjusted to a common BW basis; n = 263) feeding for a 140-d period beginning about 2 mo after w...

  3. Increased restrictive feeding practices are associated with reduced energy density in 4–6-year-old, multi-ethnic children at ad libitum laboratory test-meals✩

    PubMed Central

    Sud, Shama; Tamayo, Nina Carmela; Faith, Myles S.; Keller, Kathleen L.

    2016-01-01

    Increased reports of restrictive feeding have shown positive relationships to child obesity, however, the mechanism between the two has not been elucidated. This study examined the relationship between reported use of restrictive feeding practices and 4–6-year-old children’s self-selected energy density (ED) and total energy intake from an ad libitum, laboratory dinner including macaroni and cheese, string beans, grapes, baby carrots, cheese sticks, pudding, milks, and a variety of sweetened beverages. A second objective explored the relationship between ED and child body mass index (BMI) z-score. Seventy (n = 70) healthy children from primarily non-Caucasian and lower socioeconomic status families participated. Mothers completed the Child Feeding Questionnaire (CFQ) to assess restrictive feeding practices. Energy density (kcal/g) values for both foods and drinks (EDfood+drink) and ED for foods only (EDfoods) were calculated by dividing the average number of calories consumed by the average weight eaten across 4 meals. Higher maternal restriction was associated with lower EDfood+drink. In overweight and obese children only, higher maternal restriction was associated with lower EDfood. There was a non-significant trend for both ED measures to be negatively associated with child BMI z-score. Overall, restrictive feeding practices were not associated with child BMI z-score. However, when analyzing separate aspects of restriction, parents reported higher use of restricting access to palatable foods but lower use of using palatable foods as rewards with heavier children. Previous reports of positive associations between child obesity and restrictive feeding practices may not apply in predominantly non-Caucasian, lower socioeconomic status cohorts of children. PMID:20594990

  4. CH{sub 4} and N{sub 2}O emissions from China’s beef feedlots with ad libitum and restricted feeding in fall and spring seasons

    SciTech Connect

    Lin, Zhi; Liao, Wenhua; Yang, Yuanyuan; Gao, Zhiling; Ma, Wenqi; Wang, Dianwu; Cao, Yufeng; Li, Jianguo; Cai, Zhenjiang

    2015-04-15

    Accurately quantifying methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions from beef operations in China is necessary to evaluate the contribution of beef cattle to greenhouse gas budgets at the national and global level. Methane and N{sub 2}O emissions from two intensive beef feedlots in the North China Plain, one with a restricted feeding strategy and high manure collection frequency and the other with an ad libitum feeding strategy and low manure collection frequency, were quantified in the fall and spring seasons using an inverse dispersion technique. The diel pattern of CH{sub 4} from the beef feedlot with an ad libitum feed strategy (single peak during a day) differed from that under a restricted feeding condition (multiple peaks during a day), but little difference in the diel pattern of N{sub 2}O emissions between two feeding strategies was observed. The two-season average CH{sub 4} emission rates of the two intensive feedlots were 230 and 198 g CH{sub 4} animal{sup −1} d{sup −1} and accounted for 6.7% and 6.8% of the gross energy intake, respectively, indicating little impact of the feeding strategy and manure collection frequency on the CH{sub 4} conversion factor at the feedlot level. However, the average N{sub 2}O emission rates (21.2 g N{sub 2}O animal{sup −1} d{sup −1}) and conversion factor (8.5%) of the feedlot with low manure collection frequency were approximately 131% and 174% greater, respectively, than the feedlot under high frequency conditions, which had a N{sub 2}O emission rate and conversion factor of 9.2 g N{sub 2}O animal{sup −1} d{sup −1} and 3.1%, respectively, indicating that increasing manure collection frequency played an important role in reducing N{sub 2}O emissions from beef feedlots. In addition, comparison indicated that China’s beef and dairy cattle in feedlots appeared to have similar CH{sub 4} conversion factors. - Highlights: • CH{sub 4} and N{sub 2}O emissions from China’s beef feedlots were

  5. Hypothalamic agouti-related protein expression is affected by both acute and chronic experience of food restriction and re-feeding in chickens.

    PubMed

    Dunn, I C; Wilson, P W; Smulders, T V; Sandilands, V; D'Eath, R B; Boswell, T

    2013-10-01

    The central melanocortin system is conserved across vertebrates. However, in birds, little is known about how energy balance influences orexigenic agouti-related protein (AGRP) and anorexigenic pro-opiomelanocortin (POMC) expression, despite the fact that commercial food restriction is critical to the efficient production of poultry meat. To enable contrasts to be made, in broiler-breeder chickens, between levels of food restriction, between birds with the same body weight but different feeding experience, and between birds moved from restricted feeding to ad lib. feeding for different periods, five groups of hens were established between 6 and 12 weeks of age with different combinations of food restriction and release from restriction. AGRP and neuropeptide Y expression in the basal hypothalamus was significantly increased by chronic restriction but only AGRP mRNA levels reflected recent feeding experience: hens at the same body weight that had recently been on ad lib. feeding showed lower expression than restricted birds. AGRP expression also distinguished between hens released from restriction to ad lib. feeding for different periods. By contrast, POMC and cocaine- and amphetamine-regulated transcript mRNA levels were not different. These results showed that AGRP mRNA not only reflected differences between a bird's weight and its potential weight or set point, but also discriminated between differing feeding histories of birds at the same body weight. Therefore, AGRP expression potentially provides an integrated measure of food intake experience and an objective tool to assess a bird's perception of satiety in feeding regimes for improved poultry welfare. PMID:23957836

  6. Voluntary feed intake, acid-base balance and partitioning of urinary nitrogen in lambs fed corn silage with added sodium bicarbonate or sodium sesquicarbonate.

    PubMed

    Phillip, L E; Hidalgo, V

    1989-08-01

    An experiment with growing lambs was designed to test the hypothesis that alterations in blood acid-base status would influence intake of corn silage. Six wethers (29 kg) were fed a diet of corn silage (36% DM, 8% CP) supplemented with 1.25% urea and .2% sulfur. At feeding time, sodium bicarbonate (NaHCO3) and sodium sesquicarbonate (NaSC) were added to the silage at levels of 0, 2% or 4% of diet DM. The treatments were arranged as a 2 x 3 factorial, and the study was conducted as a 6 x 4 incomplete latin square with four 17-d periods. Voluntary intake of OM was not different (P greater than .05) between NaHCO3 (1,008 g/d) and NaSC (1,041 g/d). There was no significant interaction between type of buffer (NaHCO3 or NaSC) and level of buffer on any of the variables measured. The progressive increase in buffer load did not alter feed intake (P greater than .05), although there was a quadratic response (P less than .05) in urine pH and a linear increase (P less than .01) in blood HCO3- 2 h after feeding. There was no evidence that lambs fed corn silage experienced metabolic acid stress. Urinary excretion of ammonia and urea were indicative of changes, although not pronounced, in ammoniuria and ureapoiesis in response to bicarbonate loading. This study implies that corn silage imposes no "acid stress" on lambs and, consequently, that there is no nutritional benefit in adding buffers to corn silage for sheep. PMID:2551870

  7. Inhibition of PCDD/F by adding sulphur compounds to the feed of a hazardous waste incinerator.

    PubMed

    Wu, Hai-Long; Lu, Sheng-Yong; Li, Xiao-Dong; Jiang, Xu-Guang; Yan, Jian-Hua; Zhou, Miao-Sheng; Wang, Hua

    2012-01-01

    Sulphur compounds, including (NH(4))(2)SO(4) and pyrite, were tested as suppressants in a hazardous waste incineration facility. The test results suggested that adding sulphur compounds only slightly reduced PCDD/F stack emissions; this restricted effect was attributed to the release of fly ash in large amounts during the sulphur adding experiments, i.e., it was due to a malfunctioning of the baghouse filter. Nevertheless, for the combined flow of flue gas+fly ash a reduction of more than 50% was achieved for the total PCDD/F concentrations and the total toxic concentrations, and an even higher inhibition capability was observed for PCDD. Also, a simulation of the thermodynamic equilibrium conditions by sulphur dioxide was conducted in the domain of experimental interest. Deactivation of catalysts, which promote PCDD/F formation, was found to be the dominant inhibition mechanism in low temperature PCDD/F formation. SO(2) could also inhibit the formation of molecular Cl(2) via the Deacon reaction, but that was not the main reason for inhibition. PMID:22113054

  8. Fertility of sows fed ad libitum with a high fibre diet during pregnancy.

    PubMed

    Peltoniemi, O A T; Tast, A; Heinonen, M; Oravainen, J; Munsterhjelm, C; Hälli, O; Oliviero, C; Hämeenoja, P; Virolainen, J V

    2010-12-01

    The effect of ad libitum (ADLIB) feeding strategy on the fertility of the group housed sow was studied in a prospective field trial during 1.5 years. All study animals farrowed under standard farrowing circumstances in crates, and they were provided with an ad libitum feeding throughout the 30-day lactation. After weaning, animals were randomly allocated to one of the two dry sow feeding strategies (AD LIB or CONT). After oestrus detection in groups, they were artificially inseminated and moved into pregnancy pens with partially slatted floor, in groups of 40 sows each. The ADLIB sows (n = 447) were loose housed and provided with ad libitum access to 7.7 MJ/kg feed high in fibre from two feeders per group. The control sows (n = 479; CONT) were also loose housed and given a standard dry sow feed in feeding stalls once a day (2.5 kg/day. The energy content of the feed was 9.3 MJ/kg NE). The feeding strategy (ADLIB vs CONT) had no effect on pregnancy rate (85.8 vs 90.9, p > 0.05), weaning to oestrus interval (7.7 vs 7.3 days, p > 0.05), piglets born alive (11.5 ± 3.5 vs 11.6 ± 3.3, p > 0.05), stillborn piglets (1.2 ± 1.8 vs 0.9 ± 1.5, p > 0.05) nor on progesterone concentration (p > 0.05). CONT sows weaned more piglets (9.7 ± 2.2 vs 9.4 ± 2.0, p < 0.01), whereas the piglets of AD LIB sows were heavier at weaning (8.8 ± 0.9 vs 8.0 ± 1.3 kg, p < 0.05). In conclusion, ad libitum feeding with a high in fibre diet during pregnancy did not affect the reproductive performance. PMID:19497024

  9. Concurrent Validity of LibQUAL+[TM] Scores: What Do LibQUAL+[TM] Scores Measure?

    ERIC Educational Resources Information Center

    Thompson, Bruce; Cook, Colleen; Kyrillidou, Martha

    2005-01-01

    The present study investigated the validity of LibQUAL+[TM] scores, and specifically how total and subscale LibQUAL+[TM] scores are associated with self-reported, library-related satisfaction and outcomes scores. Participants included 88,664 students and faculty who completed the American English (n[AE] = 69,494) or the British English (n[BE] =…

  10. Holocene closure of Lib Pond, Marshall Islands.

    PubMed

    Myhrvold, Conor L; Janny, Fran; Nelson, Daniel; Ladd, S Nemiah; Atwood, Alyssa; Sachs, Julian P

    2014-01-01

    Well-preserved sediment from closed water bodies of atolls such as Lib Pond are rare opportunities to reconstruct the past regional climate, which pieced together across a latitude and longitude range identify the range of movement patterns of wider scale climate phenomena such as the Intertropical Convergence Zone (ITCZ) and El Niño Southern Oscillation (ENSO). We conducted the first physico-chemical survey of Lib Pond, a shallow, closed-water saline lake located on remote and difficult to access Lib Island in the Marshall Islands at 8° 18' 48.99″ N, 167 22' 51.90″ E in the Pacific Ocean, in July 2009. We performed a bathymetric survey, recorded salinity, dissolved oxygen, pH, and temperature profiles, monitored the tidal variability, and conducted a vegetation survey surrounding the lake. From bathymetric data we calculated the lake volume, which we used to estimate the lake's salt budget, and ultimately the residence time of water in the lake basin. We took a series of sediment cores from the lake, cores which indicate Lib Island's changing environment and climate. Radiocarbon measurements determined sediment age, and reveal significant mixing over the last 2 ka of deposition. We conclude that prior to 3 ka, Lib Island was an atoll with a central lagoon connected to the open ocean, which was then closed off from the open ocean to form the brackish system that exists today. We predict that the sediment accumulation in Lib Pond evident today will continue. As seawater is inhibited from exchanging with fresh water, Lib Pond will become a shallower lake with increasingly fresh water. PMID:24638020

  11. Holocene Closure of Lib Pond, Marshall Islands

    PubMed Central

    Myhrvold, Conor L.; Janny, Fran; Nelson, Daniel; Ladd, S. Nemiah; Atwood, Alyssa; Sachs, Julian P.

    2014-01-01

    Well-preserved sediment from closed water bodies of atolls such as Lib Pond are rare opportunities to reconstruct the past regional climate, which pieced together across a latitude and longitude range identify the range of movement patterns of wider scale climate phenomena such as the Intertropical Convergence Zone (ITCZ) and El Niño Southern Oscillation (ENSO). We conducted the first physico-chemical survey of Lib Pond, a shallow, closed-water saline lake located on remote and difficult to access Lib Island in the Marshall Islands at 8° 18′ 48.99″ N, 167 22′ 51.90″ E in the Pacific Ocean, in July 2009. We performed a bathymetric survey, recorded salinity, dissolved oxygen, pH, and temperature profiles, monitored the tidal variability, and conducted a vegetation survey surrounding the lake. From bathymetric data we calculated the lake volume, which we used to estimate the lake's salt budget, and ultimately the residence time of water in the lake basin. We took a series of sediment cores from the lake, cores which indicate Lib Island's changing environment and climate. Radiocarbon measurements determined sediment age, and reveal significant mixing over the last 2 ka of deposition. We conclude that prior to 3 ka, Lib Island was an atoll with a central lagoon connected to the open ocean, which was then closed off from the open ocean to form the brackish system that exists today. We predict that the sediment accumulation in Lib Pond evident today will continue. As seawater is inhibited from exchanging with fresh water, Lib Pond will become a shallower lake with increasingly fresh water. PMID:24638020

  12. Ad libitum Pasture Feeding in Late Pregnancy Does Not Improve the Performance of Twin-bearing Ewes and Their Lambs

    PubMed Central

    Corner-Thomas, R. A.; Back, P. J.; Kenyon, P. R.; Hickson, R. E.; Ridler, A. L.; Stafford, K. J.; Morris, S. T.

    2015-01-01

    The present study evaluated the effect of controlled ryegrass-white clover herbage availability from day 128 until day 142 of pregnancy in comparison to unrestricted availability, on the performance of twin-bearing ewes of varying body condition score (BCS; 2.0, 2.5, or 3.0) and their lambs. It was hypothesised that under conditions of controlled herbage availability, the performance of lambs born to ewes with a greater BCS would be greater than those born to ewes with a lower BCS. During the period that the nutritional regimens were imposed, the pre- and post-grazing herbage masses of the Control regimen (1,070±69 and 801±30 kg dry matter [DM]/ha) were lower than the ad libitum regimen (1,784±69 and 1,333±33 kg DM/ha; p<0.05). The average herbage masses during lactation were 1,410±31 kg DM/ha. Nutritional regimen had no effect on ewe live weight, BCS and back fat depth or on lamb live weight, indices of colostrum uptake, maximal heat production, total litter weight weaned or survival to weaning (p>0.05). The difference in ewe BCSs and back fats observed among body condition groups was maintained throughout pregnancy (p<0.05). At weaning, ewes from the BCS2.0 group had lower BCS and live weight (2.4±0.2, 74.3±2.6 kg) than both the BCS2.5 (2.6±0.2, 78.6±2.4 kg) and BCS3.0 ewes (2.7±0.2, 79.0±2.6 kg; p<0.05), which did not differ (p>0.05). Ewe BCS group had no effect on lamb live weight at birth or weaning or on maximal heat production (p>0.05). Serum gamma glutamyl transferase concentrations of lambs born to BCS3.0 ewes were higher within 36 hours of birth than lambs born to BCS2.0 ewes and BCS2.5 ewes (51.8±1.9 vs 46.5±1.9 and 45.6±1.9 IU/mL, respectively [p<0.05]). There was, however, no effect of ewe body condition on lamb plasma glucose concentration (p>0.05). Lamb survival was the only lamb parameter that showed an interaction between ewe nutritional regimen and ewe BCS whereby survival of lambs born to BCS2.5 and BCS3.0 ewes differed but only

  13. LIBS spectroscopic classification relative to compressive sensing

    NASA Astrophysics Data System (ADS)

    Griffin, Steven T.; Jacobs, Eddie; Furxhi, Orges

    2011-05-01

    Laser Induced Breakdown Spectroscopy (LIBS) utilizes a diversity of standard spectroscopic techniques for classification of materials present in the sample. Pre-excitation processing sometimes limits the analyte to a short list of candidates. Prior art demonstrates that sparsity is present in the data. This is sometimes characterized as identification by components. Traditionally, spectroscopic identification has been accomplished by an expert reader in a manner typical for MRI images in the medicine. In an effort to automate this process, more recent art has emphasized the use of customized variations to standard classification algorithms. In addition, formal mathematical proofs for compressive sensing have been advanced. Recently the University of Memphis has been contracted by the Spectroscopic Materials Identification Center to advance and characterize the sensor research and development related to LIBS. Applications include portable standoff sensing for improvised explosive device detection and related law enforcement and military applications. Reduction of the mass, power consumption and other portability parameters is seen as dependent on classification choices for a LIBS system. This paper presents results for the comparison of standard LIBS classification techniques to those implied by Compressive Sensing mathematics. Optimization results and implications for portable LIBS design are presented.

  14. A compact LIBS system for industrial applications

    NASA Astrophysics Data System (ADS)

    Noharet, B.; Sterner, C.; Irebo, T.; Gurell, J.; Bengtson, A.; Vainik, R.; Karlsson, H.; Illy, E.

    2015-03-01

    In recent years, laser-induced breakdown spectroscopy (LIBS) has been established as a promising analytical tool for online chemical analysis. The emitted light spectrum is analyzed for instantaneous determination of the elemental composition of the sample, enabling on-line classification of materials. Two major strengths of the technique are the possibilities to perform both fast and remote chemical analysis to determine the elemental composition of the samples under test. In order to reduce the size of LIBS systems, the use of a compact Q-switched diode-pumped solid-state laser (DPSSL) in a LIBS system is evaluated for the industrial sorting of aluminium alloys. The DPSSL, which delivers 150μJ pulses of high beam quality at more than 7KHz repetition rate, provides irradiance on the target that is appropriate for LIBS measurements. The experimental results indicate that alloy classification and quantitative analysis are possible on scrap aluminium samples placed 50 cm apart from the focusing and collecting lenses, without sample preparation. Similar calibration curves and limits of detection are obtained for traditional high-energy low-frequency flashlamp-pumped and low-energy high-frequency diode-pumped lasers, showing the applicability of compact diode-pumped lasers for industrial LIBS applications.

  15. astLib: Tools for research astronomers

    NASA Astrophysics Data System (ADS)

    Hilton, Matt; Boada, Steven

    2016-07-01

    astLib is a set of Python modules for performing astronomical plots, some statistics, common calculations, coordinate conversions, and manipulating FITS images with World Coordinate System (WCS) information through PyWCSTools, a simple wrapping of WCSTools (ascl:1109.015).

  16. Laser-Induced Breakdown Spectroscopy (LIBS): specific applications

    NASA Astrophysics Data System (ADS)

    Trtica, M. S.; Savovic, J.; Stoiljkovic, M.; Kuzmanovic, M.; Momcilovic, M.; Ciganovic, J.; Zivkovic, S.

    2015-12-01

    A short overview of Laser Induced Breakdown Spectroscopy (LIBS) with emphasis on the new trends is presented. Nowadays, due to unique features of this technique, LIBS has found applications in a great variety of fields. Achievements in the application of LIBS in nuclear area, for hazardous materials detection and in geology were considered. Also, some results recently obtained at VINCA Institute, with LIBS system based on transversely excited atmospheric (TEA) CO2 laser, are presented. Future investigations of LIBS will be oriented toward further improvement of the analytical performance of this technique, as well as on finding new application fields.

  17. Episodic sucrose intake during food restriction increases synaptic abundance of AMPA receptors in nucleus accumbens and augments intake of sucrose following restoration of ad libitum feeding.

    PubMed

    Peng, X-X; Lister, A; Rabinowitsch, A; Kolaric, R; Cabeza de Vaca, S; Ziff, E B; Carr, K D

    2015-06-01

    Weight-loss dieting often leads to loss of control, rebound weight gain, and is a risk factor for binge pathology. Based on findings that food restriction (FR) upregulates sucrose-induced trafficking of glutamatergic AMPA receptors to the nucleus accumbens (NAc) postsynaptic density (PSD), this study was an initial test of the hypothesis that episodic "breakthrough" intake of forbidden food during dieting interacts with upregulated mechanisms of synaptic plasticity to increase reward-driven feeding. Ad libitum (AL) fed and FR subjects consumed a limited amount of 10% sucrose, or had access to water, every other day for 10 occasions. Beginning three weeks after return of FR rats to AL feeding, when 24-h chow intake and rate of body weight gain had normalized, subjects with a history of sucrose intake during FR consumed more sucrose during a four week intermittent access protocol than the two AL groups and the group that had access to water during FR. In an experiment that substituted noncontingent administration of d-amphetamine for sucrose, FR subjects displayed an enhanced locomotor response during active FR but a blunted response, relative to AL subjects, during recovery from FR. This result suggests that the enduring increase in sucrose consumption is unlikely to be explained by residual enhancing effects of FR on dopamine signaling. In a biochemical experiment which paralleled the sucrose behavioral experiment, rats with a history of sucrose intake during FR displayed increased abundance of pSer845-GluA1, GluA2, and GluA3 in the NAc PSD relative to rats with a history of FR without sucrose access and rats that had been AL throughout, whether they had a history of episodic sucrose intake or not. A history of FR, with or without a history of sucrose intake, was associated with increased abundance of GluA1. A terminal 15-min bout of sucrose intake produced a further increase in pSer845-GluA1 and GluA2 in subjects with a history of sucrose intake during FR

  18. Effect of prepartal ad libitum feeding of grass silage on transcriptional adaptations of the liver and subcutaneous adipose tissue in dairy cows during the periparturient period.

    PubMed

    Selim, S; Kokkonen, T; Taponen, J; Vanhatalo, A; Elo, K

    2015-08-01

    Prepartal energy overfeeding may predispose cows to a state of increased insulin resistance with greater lipolysis after parturition. The aim of the study was to evaluate the effects of prepartal overfeeding in terms of abundant grass silage ration on the liver and subcutaneous adipose tissue (SAT) gene expression around parturition. Sixteen multiparous Finnish Ayrshire dairy cows were fed ad libitum either grass silage [high energy, HE; 144 MJ/d of metabolizable energy (ME) intake, n=8] or a mixture of grass silage, wheat straw, and rapeseed meal [55:40:5 (CON), 109 MJ/d of ME, n=8] during the dry period (58.2±4.89 d, mean ± standard deviation). Tissue biopsies and blood samples were collected at -14 (±4.98), 1, and 7 d relative to the actual parturition date. The HE cows had greater total dry matter intake, ME intake, and ME balance during the dry period than the CON cows. Compared with CON, the increases in body weight and body condition score were greater in HE during the dry period. Milk yield during the first 2 wk of lactation was not different between the groups. Plasma glucose, nonesterified fatty acids, insulin, glucagon, and β-hydroxybutyrate did not differ between the groups during the transition period. Dietary treatment did not affect hepatic triglyceride content; however, a delayed increase in hepatic total lipid content was observed in the HE cows at d 1 postpartum. Hepatic cytosolic phosphoenolpyruvate carboxykinase 1 mRNA expression was lower in HE than in CON at d 1 and 7 postpartum. Adiponectin receptor 1 and 2 mRNA abundance tended to be lower in SAT of HE than CON. Lower lipoprotein lipase, leptin, and stearoyl-coenzyme A desaturase mRNA abundances were observed at d 7 postpartum in SAT of the HE cows compared with the CON cows. We concluded that prepartal ad libitum feeding of grass silage may decrease insulin sensitivity and lipogenesis in SAT during peripartal period and may attenuate the increase of hepatic gluconeogenic capacity from

  19. Progress in LIBS for landmine detection

    NASA Astrophysics Data System (ADS)

    Gottfried, Jennifer L.; Harmon, Russell S.; La Pointe, Aaron

    2009-05-01

    The ability to interrogate objects buried in soil and ascertain their chemical composition in-situ would be an important capability enhancement for both military and humanitarian demining. Laser Induced Breakdown Spectroscopy (LIBS) is a simple spark spectrochemical technique using a pulsed laser. Recent developments in broadband and man-portable LIBS provide the capability for the real-time detection at very high sensitivity of all elements in any target material because all chemical elements emit in the 200-940 nm spectral region. This technological advance offers a unique potential for the development of a rugged and reliable man-portable or robot-deployable chemical sensor that would be capable of both in-situ point probing and chemical sensing for landmine detection. Broadband LIBS data was acquired under laboratory conditions for more than a dozen different types of anti-personnel and anti-tank landmine casings from four countries plus a set of antitank landmine simulants. Subsequently, a statistical classification technique (partial least squares discriminant analysis, PLS-DA) was used to discriminate landmine casings from the simulants and to assign "unknown" spectra to a mine type based upon a library classification approach. Overall, a correct classification success of 99.0% was achieved, with a misclassification rate of only 1.8%. This performance illustrates the potential that LIBS has to be developed into a field-deployable device that could be utilized as a confirmatory sensor in landmine detection. The operational concept envisioned is a small LIBS system that is either man-portable or robot-deployed in which a micro-laser is contained in the handle of a deminer's probe, with laser light delivered and collected through an optical fiber in the tapered tip of the probe. In such a configuration, chemical analysis could be readily accomplished by LIBS after touching the buried object that one is interested in identifying and using real-time statistical

  20. TasmataLibV0.1

    2005-01-20

    TasmataLib is a library implementing multiple volume rendering algorithms for computing simulated radiographs. The library will include implementations for several commercial graphics processing units (GPUs) as well as a software reference implementation. The library will additionally include methods for generating opacity tables based on the Evaluated Photon Data Library (EPDL97, UCRL-50400). The EPDL will be included in the source code release.

  1. Spectroscopic material determination via LIBS and CRDS

    NASA Astrophysics Data System (ADS)

    Griffin, Steven T.

    2009-05-01

    Laser Induced Spectroscopy (LIBS) and Cavity Ring Down Spectroscopy (CRDS) are promising chemical sensor technologies for small mobile robotic platforms. LIBS leverages the natural surface adsorption from the atmosphere to interior and exterior surfaces for signal enhancement. In this work, a material or class-specific adsorption surface is combined with a miniature version of a CRDS ring cavity to achieve a similar signal enhancement for CRDS. The combination of LIBS and CRDS allow the analysis of both classes of materials - those with long adsorption times to permanent surfaces such as walls and those that require real time sampling of ambient concentrations. This paper emphasizes issues related to package miniaturization, power budget limitations and ruggedness as well as basic performance modeling of the instruments. Comprehensive sensing issues for material specific micro-detectors will be addressed. Computer simulations and some data are presented. Applications considered include the determination of need for remediation and the determination of the effectiveness of remediation techniques as well as the detection of hazards and intelligence gathering.

  2. Effect of different feeding regimes on pre-weaning growth rumen fermentation and its influence on post-weaning performance of lambs.

    PubMed

    Bhatt, R S; Tripathi, M K; Verma, D L; Karim, S A

    2009-10-01

    Influence of pre-weaning live weight on post-weaning growth performance was assessed on thirty-nine 15-day-old Indian native lambs, randomly fed in three equal groups until 180 days of age. During pre-weaning phase lambs were maintained under feeding regimen of grazing (C-0; Control), grazing and ad lib creep mixture supplementation (C-AL) or grazing, with ad lib creep mixture and milk replacer supplementation (C-ALMR). Lambs were allowed to suckle respective dam in morning and evening till 90 days of age, and fed ad lib green leaves of Ailanthus excelsa after grazing. After weaning all lambs were maintained on grazing and ad lib finisher concentrates supplementation. Pre-weaning performance of lambs in terms of weaning weight (17.2 kg), average daily gain (ADG; 154 g) and feed conversion ratio 3.73 was higher (p < 0.01) in C-ALMR lambs but total gain and ADG were similar among three groups during post-weaning phase. However, improved pre-weaning plane of nutrition and growth rate increased (p < 0.01) finishing weight (FW) of lambs in C-AL, 33 kg and C-ALMR, 32 kg. Dry matter intake was significantly (p < 0.01) higher in C-AL and C-ALMR lambs due to combined effect of feeding. Rumen pH was lowest (p = 0.049) in C-AL lambs. Rumen ciliate protozoa population (10(4)/ml) decreased in C-ALMR lambs (4.3) but increased in C-AL lambs (50.0) more so in C-0 Lambs (19.8). Concentrate feeding of C-AL lamb improved nutrient digestibility. Lambs of C-0 group consumed more DM during post-weaning phase that improved growth performance, while nutrient digestibility was not affected by pre-weaning nutrition. Thus, pre-weaning nutrition has significant influence on FW, however influence of milk replacer feeding on lamb growth need further studies. PMID:19141102

  3. Biomedical applications of laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Unnikrishnan, V. K.; Nayak, Rajesh; Bhat, Sujatha; Mathew, Stanley; Kartha, V. B.; Santhosh, C.

    2015-03-01

    LIBS has been proven to be a robust elemental analysis tool attracting interest because of the wide applications. LIBS can be used for analysis of any type of samples i.e. environmental/physiological, regardless of its state of matter. Conventional spectroscopy techniques are good in analytical performance, but their sample preparation method is mostly destructive and time consuming. Also, almost all these methods are incapable of analysing multi elements simaltaneously. On the other hand, LIBS has many potential advantages such as simplicity in the experimental setup, less sample preparation, less destructive analysis of sample etc. In this paper, we report some of the biomedical applications of LIBS. From the experiments carried out on clinical samples (calcified tissues or teeth and gall stones) for trace elemental mapping and detection, it was found that LIBS is a robust tool for such applications. It is seen that the presence and relative concentrations of major elements (calcium, phosphorus and magnesium) in human calcified tissue (tooth) can be easily determined using LIBS technique. The importance of this study comes in anthropology where tooth and bone are main samples from which reliable data can be easily retrieved. Similarly, elemental composition of bile juice and gall stone collected from the same subject using LIBS was found to be similar. The results show interesting prospects for LIBS to study cholelithiasis (the presence of stones in the gall bladder, is a common disease of the gastrointestinal tract) better.

  4. Developing mobile LIBS solutions for real world applications

    NASA Astrophysics Data System (ADS)

    Li, Qun; Li, Jing; Bakeev, Katherine; Wang, Sean

    2015-06-01

    We present a new type of handheld laser-induced breakdown spectroscopy (LIBS) spectrometer for developing mobile atomic spectroscopy solutions for real world applications. A micro diode-pumped passive Q-switched solid-state laser with high repetition rate of well above 1 kHz in comparison to 1-10 Hz as used in a traditional LIBS instrument is employed to produce a train of laser pulses. The laser beam is further fast scanned over a pre-defined area, hence generating several hundreds of micro-plasmas per second at different locations. Synchronized miniature CCD array spectrometer modules collect the LIBS signal and generate LIBS spectra. By adjusting the integration time of the spectrometer to cover a plurality of periods of the laser pulse train, the spectrometer integrates the LIBS signal produced by this plurality of laser pulses. Hence the intensity of the obtained LIBS spectrum can be greatly improved to increase the signal-to-noise ratio (SNR). This unique feature of the high repetition rate laser based LIBS system allows it to measure elements at trace levels, hence reducing the limit of detection (LOD). The increased signal intensity also lessens the sensitivity requirement for the optical spectrometer. In addition, the energy of the individual laser pulse can be reduced in comparison to traditional LIBS system to obtain the same signal level, making the laser pulse less invasive to the sample. The typical measurement time is within 1 second. Several examples of real world applications will be presented.

  5. Implementing LibGuides 2: An Academic Case Study

    ERIC Educational Resources Information Center

    Duncan, Vicky; Lucky, Shannon; McLean, Jaclyn

    2015-01-01

    Since 1997, the University of Saskatchewan Library has used "subject pages" to highlight key library resources. When Springshare announced it was launching LibGuides v2, a project team was assembled to transition a mixture of locally produced guides and guides created with the original LibGuides v1 software. This article synthesizes best…

  6. Expanding Library Services and Instruction Through LibGuides.

    PubMed

    Ream, Tim; Parker-Kelly, Darlene

    2016-01-01

    Beginning in 2012, the Charles R. Drew University (CDU) Health Sciences Library used LibGuides in a number of innovative ways. Librarians constructed e-book databases, in-depth tutorials on technology-related topics, and web pages highlighting special events. To assess similar LibGuides innovation, CDU librarians developed an eight-question survey distributed to health sciences and hospital libraries throughout Southern California and Arizona. Results showed that libraries used LibGuides primarily to deliver access to online resources and to provide supplementary materials supporting instruction. Responses also revealed that many libraries had not yet adopted LibGuides. These findings were analyzed and compared to past and current LibGuides design at CDU. PMID:27391185

  7. Feeding-elicited cataplexy in orexin knockout mice

    PubMed Central

    Clark, Erika L.; Baumann, Christian R.; Cano, Georgina; Scammell, Thomas E.; Mochizuki, Takatoshi

    2009-01-01

    Mice lacking orexin/hypocretin signaling have sudden episodes of atonia and paralysis during active wakefulness. These events strongly resemble cataplexy, episodes of sudden muscle weakness triggered by strong positive emotions in people with narcolepsy, but it remains unknown whether murine cataplexy is triggered by positive emotions. To determine whether positive emotions elicit murine cataplexy, we placed orexin knockout (KO) mice on a scheduled feeding protocol with regular or highly palatable food. Baseline sleep/wake behavior was recorded with ad lib regular chow. Mice were then placed on a scheduled feeding protocol in which they received 60% of their normal amount of chow 3 hr after dark onset for the next 10 days. Wild-type and KO mice rapidly entrained to scheduled feeding with regular chow, with more wake and locomotor activity prior to the feeding time. On day 10 of scheduled feeding, orexin KO mice had slightly more cataplexy during the food-anticipation period and more cataplexy in the second half of the dark period, when they may have been foraging for residual food. To test whether more palatable food increases cataplexy, mice were then switched to scheduled feeding with an isocaloric amount of Froot Loops, a food often used as a reward in behavioral studies. With this highly palatable food, orexin KO mice had much more cataplexy during the food-anticipation period and throughout the dark period. The increase in cataplexy with scheduled feeding, especially with highly palatable food, suggests that positive emotions may trigger cataplexy in mice, just as in people with narcolepsy. Establishing this connection helps validate orexin KO mice as an excellent model of human narcolepsy and provides an opportunity to better understand the mechanisms that trigger cataplexy. PMID:19362119

  8. Comparative LIBS Analysis Of Calcified Tissues

    SciTech Connect

    Abdel-Salam, Z. A.; Harith, M. A.

    2008-09-23

    Signal enhancement, limits of detection, and relevance to environmental concentration for element in calcified tissues using LIBS with single and double laser pulses will be presented. These measurements were performed on three calcified tissues representing different matrices, namely enamel of human teeth, shells and eggshells. This method depends on the role of the laser induced shock wave on the ionization rate of the ablated target material atoms. The effect of the laser single and double pulse on the ionic to atomic ratio of calcium and magnesium spectral emission lines, CaII/CaI and MgII/MgI, will be presented and compared with the previous results and its relevance to the target material hardness. The results show that in case of single pulse the intensity ratios in calcium are higher than the double pulse while there is no appreciable difference between both in case of magnesium.

  9. Adipose tissue partitioning of limit-fed beef cattle and beef cattle with ad libitum access to feed differing in adaptation to heat.

    PubMed

    Sprinkle, J E; Ferrell, C L; Holloway, J W; Warrington, B G; Greene, L W; Wu, G; Stuth, J W

    1998-03-01

    We compared fat distribution and lipoprotein lipase (LPL) activity in steers differing in adaptability to the subtropics. Steers were fed a grain diet (3.13 Mcal ME/kg DM) at limited (150 kcal ME x kg[-.75] x d[-1]; .23 kg ADG) or ad libitum levels for 140 d, then slaughtered. Sixteen British- (8 Angus, 8 Hereford; S), 16 Boran- (R), 16 Brahman- (B), and 16 Tuli- (T) cross steers from MARC III composite cows were used. Adipose tissue samples from perirenal, omental, and subcutaneous depots were analyzed for LPL activity. Carcass measurements including omental, external, and seam fat trim from 1/ 2 of the carcass were measured. Subcutaneous fat had greater (P < .05) LPL activity than fat from the other depots. Generally, there were no differences (P > .05) in fat distribution for steers fed at limited levels. Means for ADG, slaughter weights, carcass weights, yield grades, and carcass lipid weights for S and B fed for ad libitum intake were greater (P < .05) than those for T and R. Marbling was greatest (P < .05) for S and did not differ (P > .05) for the other breeds with ad libitum intake. Factor analysis of fat depots for animals with ad libitum intake indicated that Bos taurus cattle differing in adaptation to heat deposited fat differently; S deposited greater (P < .05) proportions of carcass fat and T deposited greater (P < .05) proportions of internal fat. It seems that accumulation of internal fat is detrimental for ADG for Bos taurus cattle. PMID:9535321

  10. Effects of feeding wheat straw or orchardgrass at ad libitum or restricted intake during the dry period on postpartum performance and lipid metabolism.

    PubMed

    Litherland, N B; Weich, W D; Hansen, W P; Linn, J G

    2012-12-01

    The objectives of this study were to investigate the effects of forage source [wheat straw (WS) or orchardgrass hay (OG)] and total amount of diet dry matter fed [ad libitum or restricted to 70% of predicted dry matter intake (DMI)] prepartum on postpartum performance. The study design was a 2×2 factorial design with 10 cows per treatment. Treatments were WS total mixed ration (TMR) ad libitum, OG TMR ad libitum, WS TMR restricted, and OG TMR restricted. The WS TMR (dry matter basis) contained 30% WS, 20.7% corn silage, 10.0% alfalfa hay, 18.2% ground corn, 16.8% soybean meal, and 4.3% molasses mineral mix (14.7% CP, 1.5 Mcal/kg of net energy for lactation, 37.0% neutral detergent fiber). The OG TMR contained 30% OG, 46.2% corn silage, 10.0% alfalfa hay, 9.5% soybean meal, and 4.3% molasses (14.2% CP, 1.5 Mcal/kg of net energy for lactation, 41.0% neutral detergent fiber). Cows received 1 lactation diet after calving (17.7% CP, 1.6 Mcal/kg of net energy for lactation, 27.3% neutral detergent fiber). Total diet DMI prepartum was higher for ad libitum than for restricted as designed, but forage source had no effect on DMI. Total tract apparent digestibilities of DM and NDF were greater for OG than for WS. Postpartum DMI expressed as a percentage of body weight for the first week of lactation was higher for ad libitum than for restricted diets. Postpartum DMI during the first 30 d of lactation was higher for OG than for WS, but no effect was observed for the amount fed prepartum. Milk yield during the first week of lactation was higher for OG than for WS; however, during the first 30 d, 3.5% fat-corrected milk yield and yield of milk fat were highest for OG TMR restricted and WS TMR ad libitum. Prepartum treatments had a limited effect on pre- and postpartum lipid metabolism; however, cows fed WS TMR ad libitum had the highest postpartum β-hydroxybutyrate. Eating behavior was observed by 10-min video scans of 24-h video surveillance for 5d pre- and postpartum

  11. Minimal invasive control of paintings cleaning by LIBS

    NASA Astrophysics Data System (ADS)

    Staicu, A.; Apostol, I.; Pascu, A.; Urzica, I.; Pascu, M. L.; Damian, V.

    2016-03-01

    In cultural heritage restoration and conservation, it has been proved that LIBS is an appropriate technique for pigments identification, analysis of multilayered paintings, and quantitative analysis of ancient materials. Generally, experiments involving the use of laser for paint cleaning and LIBS in order to identify the composition of the removed material are made. Here, we report LIBS studies on mastic and dammar varnishes removal using visible (532 nm) and UV (266 nm) laser pulses (5 ns) with fluences in the range 0.6-4.4 J/cm2. The studied varnish layers were on-purpose painted on glass supports or were part of several mock-up samples having dammar or mastic as final layer - gold foil, yellow ochre or cobalt blue egg tempera as painting layer - chalk or acrylic ground as link to an wooden support. LIBS was used to monitor the laser induced stepwise selective removal of the layers and to analyze their composition.

  12. CosmoBolognaLib: C++ libraries for cosmological calculations

    NASA Astrophysics Data System (ADS)

    Marulli, F.; Veropalumbo, A.; Moresco, M.

    2016-01-01

    We present the CosmoBolognaLib, a large set of Open Source C++ numerical libraries for cosmological calculations. CosmoBolognaLib is a living project aimed at defining a common numerical environment for cosmological investigations of the large-scale structure of the Universe. In particular, one of the primary focuses of this software is to help in handling astronomical catalogues, both real and simulated, measuring one-point, two-point and three-point statistics in configuration space, and performing cosmological analyses. In this paper, we discuss the main features of this software, providing an overview of all the available C++ classes implemented up to now. Both the CosmoBolognaLib and their associated doxygen documentation can be freely downloaded at https://github.com/federicomarulli/CosmoBolognaLib. We provide also some examples to explain how these libraries can be included in either C++ or Python codes.

  13. SPICE-SANDIA.LIB. Library Analog Semiconductor Devices SPICE Simulators

    SciTech Connect

    Deveney, M.F.; Archer, W.; Bogdan, C.

    1996-06-06

    SPICE-SANDIA.LIB is a library of parameter sets and macromodels of semiconductor devices. They are used with Spice-based (SPICE is a program for electronic circuit analysis) simulators to simulate electronic circuits.

  14. The Chemcam LIBS and Imaging Instrument Suite on the Curiosity Mars Rover, and Terrestrial Field Testing of LIBS

    NASA Astrophysics Data System (ADS)

    Wiens, R. C.; Clegg, S. M.; Barefield, J. E., II; Maurice, S.

    2014-12-01

    The Curiosity rover that landed on Mars in 2012 includes an instrument suite consisting of a laser-induced breakdown spectrometer (LIBS) and a remote micro-imager (RMI). The LIBS is effectively the first Mars microprobe, as its interrogation region is 0.35-0.5 mm in diameter; it can access targets up to 7 m from the rover. The LIBS pulsed laser excites atoms and ions from the target, creating a plasma that emits light at characteristic wavelengths. When calibrated, LIBS provides quantitative elemental abundances. The elements observed on Mars include H, Li, O, F, Na, Mg, Al, Si, S, Cl, Ca, Ti, Cr, Mn, Fe, Zn, Rb, Sr, Ba. The first few laser shots clear the surface of dust, allowing unobscured analyses of the targets. Within the first two years of operation ChemCam has returned > 150,000 spectra from > 4,000 locations along the rover traverse. The RMI is the highest resolution (0.04 mrad) remote imager on the rover and provides context before/after images of the LIBS targets as well as long-distance stand-alone imagery. The ChemCam LIBS instrument concept was developed based on laboratory LIBS instrumentation. For terrestrial field work ChemCam's design with its unshielded laser beam is an eye safety hazard. However, hand-held devices with closed laser-beam designs have been developed. In order to provide a realistic field test prior to the launch of the rover the ChemCam team fielded a backpack LIBS system featuring a shielded laser beam. The system was calibrated using the same 66 geological standards used by the ChemCam instrument prior to flight. During the field test, data was sent remotely to a team back at Los Alamos, effectively imitating operations on Mars and data analysis on the ground. The ground team successfully reported accurate results, identifying the site as rich in kaolinite clay soils.

  15. LIBS controls characterization of predictor corrector-based LIBS data collection

    NASA Astrophysics Data System (ADS)

    Sanders, Alex; Griffin, Steven T.

    2013-05-01

    Portable LIBS sensor communication bandwidth limitations favor local material classification for low power consumption. Partial Least Squares - Discriminant Analysis (PLS-DA) and Principle Component Analysis (PCA) have been implementation via general purpose computers and are accepted for some Department of Defense applications. Prior publications address the creation of a low mass, low power, robust hardware spectra classifier for a limited set of predetermined materials in an atmospheric matrix. The incorporation of a PCA or a PLS-DA classifier into a predictorcorrector implementation on a TI6701 has been developed. The performance modeling of the control system with an emphasis on further optimization needs addressing. This paper characterizes, from a control system standpoint, the predictor-corrector architecture applied to LIBS data collection. In addition, the application of this as a material classifier is presented. Updates in the model implemented on a low power multi-core DSP will be presented as well. Performance comparisons to alternative control system structures will be considered.

  16. Study of different concentric rings inside gallstones with LIBS.

    PubMed

    Pathak, Ashok Kumar; Singh, Vivek Kumar; Rai, Nilesh Kumar; Rai, Awadhesh Kumar; Rai, Pradeep Kumar; Rai, Pramod Kumar; Rai, Suman; Baruah, G D

    2011-07-01

    Gallstones obtained from patients from the north-east region of India (Assam) were studied using laser-induced breakdown spectroscopy (LIBS) technique. LIBS spectra of the different layers (in cross-section) of the gallstones were recorded in the spectral region 200-900 nm. Several elements, including calcium, magnesium, manganese, copper, silicon, phosphorus, iron, sodium and potassium, were detected in the gallstones. Lighter elements, including carbon, hydrogen, nitrogen and oxygen were also detected, which demonstrates the superiority of the LIBS technique over other existing analytical techniques. The LIBS technique was applied to investigate the evolution of C(2) swan bands and CN violet bands in the LIBS spectra of the gallstones in air and an argon atmosphere. The different layers (dark and light layers) of the gallstones were discriminated on the basis of the presence and intensities of the spectral lines for carbon, hydrogen, nitrogen, oxygen and copper. An attempt was also made to correlate the presence of major and minor elements in the gallstones with the common diet of the population of Assam. PMID:21318345

  17. Sham feeding is inhibited by dietary-induced obesity in rats.

    PubMed

    Vanderweele, D A; Van Itallie, T B

    1983-10-01

    A group of six female, albino rats were maintained on a cafeteria diet of cookies, milk, and elevated-fat (shortening), rat-chow mixture and rat chow while a similar group received only rat chow ad lib for 17 weeks. When the groups differed significantly in mean body weight (obese-387.5 g, controls-287.2 g; p less than 0.001), gastric fistulas were implanted in each animal. After recovery, the rats were adapted to a liquid diet and assessed for sham feeding. Control-fed, normal-body-weight subjects showed substantial sham feeding when ingesting the Vivonex with the fistulas open compared to fistula-closed intake; meal frequency, meal size (apart from the initial meal) and total food intake were significantly increased while the satiety ratios following each meal were significantly decreased. Obese animals showed no significant increased feeding and satiety ratios were unreliably altered; while normal-body-weight controls increased 4-hr food intakes by 93% and halved their mean satiety ratios the obese animals showed an 8% increase in 4-hr food intake and only a 22% decrease in mean satiety ratios. We offer the hypothesis that, when animals are induced to become obese by palatable and varied diets which are then terminated, the anorexia produced is independent of gastrointestinal interactions inasmuch as that anorexia extends to sham feeding. PMID:6361815

  18. Detection and monitoring of CWA and BWA using LIBS

    NASA Astrophysics Data System (ADS)

    Landström, L.; Larsson, A.; Gradmark, P.-Å.; Örebrand, Lillermor; Andersson, P. O.; Wästerby, Pär.; Tjärnhage, Torbjörn

    2014-05-01

    Results related to laser induced breakdown spectroscopy (LIBS) as an analytical tool for applications regarding CWA and BWA detection/monitoring will be presented and discussed in this paper. A `real-time' aerosol analysis set-up using LIBS on single μm-sized particles (sampled from ambient air into a particle stream) has been developed and evaluated. Here, a two-stage triggering unit ensures a high hit-rate of the sampled aerosol particles and the optical emission from the laser induced plasma is collected and coupled into an echelle spectrometer equipped with an intensified CCD detector. Each CCD image (echellogram), optimally originating from a single μm-sized particle, is then analyzed and the result treated by an alarm algorithm built from a database using multivariate data analysis. The database signatures of simulant agents and interferents were obtained in controlled atmospheres (aerosol chamber/wind tunnel) as well as from measurements in different ambient background. The LIBS bioaerosol system with alarm algorithm was also tested in `real-life' settings (subway station) during simulant dispersions. Painted surfaces have also been analyzed by LIBS to obtain information about residues of organophosphates on, or within, the paint. Depth analysis has been performed, which illustrated the possibility to monitor diffusion and penetration behavior of neat CWAs and simulant chemicals in the paint layer by following the intensity of phosphorous emission lines in single shot LIBS spectra as function of number of laser pulses. In addition, LIBS analysis was also performed after simple ethanol decontamination procedures, after which P emission lines still could be observed. The possibilities and challenges associated with the different set-ups and applications will be briefly discussed in connection with the presented results.

  19. PV_LIB Toolbox v. 1.3

    2015-12-09

    PV_LIB comprises a library of Matlab? code for modeling photovoltaic (PV) systems. Included are functions to compute solar position and to estimate irradiance in the PV system’s plane of array, cell temperature, PV module electrical output, and conversion from DC to AC power. Also included are functions that aid in determining parameters for module performance models from module characterization testing. PV_LIB is open source code primarily intended for research and academic purposes. All algorithms aremore » documented in openly available literature with the appropriate references included in comments within the code.« less

  20. LIBS and LA-ICP-MS; Old techniques, new approaches

    NASA Astrophysics Data System (ADS)

    Mueller, P. A.; Foster, D. A.; Gonzalez, J.; Colucci, M.; Russo, R.

    2012-12-01

    Over the past decade laser ablation in-situ solid sampling for chemical analysis with an ICP-MS analyzer (LA-ICP-MS, single and multi-collector) has become a generally accepted technique across a wide range of disciplines (geochemistry, forensic science, life sciences, etc). More recently, Laser Induced Breakdown Spectrometry (LIBS) has developed into a complementary technique that offers full spectral analysis of the laser plasma without the need for a mass spectrometer. Both techniques provide in-situ solid sample elemental and isotopic analysis at high spatial resolution (<5 microns) with minimal sample preparation. LA-ICP-MS affords the analyst low detection limits (ppb) and the ability to optimize across a specific mass range for high precision element or isotope ratios. LIBS, while providing slightly higher detection limits (ppm), allows for simultaneous and near complete spectral coverage of the laser plasma. Both techniques are capable of producing semi-quantitative and quantitative data. Integration of a LA and LIBS system could be a powerful tool to allow full spectral element and isotope/element ratio data on the same laser plume (plasma and particulates). Although LIBS and LA typically operate under different conditions of pulse length, spot size, and energy, the ability to capture elemental abundance information from the light that is otherwise wasted during LA makes an important complement to the limited number of ions measured in multi-collector ICP-MS analyses. Such an approach would not require the compromises in sampled volume associated with either split-streams (two ICP-MS systems required; diluted aerosol streams) or with peak switching in the MS (magnetic or electrostatic) because extraction of light-based information does not impact the number of ions measured for isotope ratios. We present LIBS experiments with UV-nanosecond lasers at 17mJ energies delivered to spot sizes of <100 μm and light directed to an ICCD detection system on NIST

  1. PV_LIB Toolbox v. 1.3

    SciTech Connect

    2015-12-09

    PV_LIB comprises a library of Matlab? code for modeling photovoltaic (PV) systems. Included are functions to compute solar position and to estimate irradiance in the PV system’s plane of array, cell temperature, PV module electrical output, and conversion from DC to AC power. Also included are functions that aid in determining parameters for module performance models from module characterization testing. PV_LIB is open source code primarily intended for research and academic purposes. All algorithms are documented in openly available literature with the appropriate references included in comments within the code.

  2. Application OF LIBS To Estimate The Age Of Broiler Breeders

    NASA Astrophysics Data System (ADS)

    Salam, Z. Abdel; Harith, M. A.

    2011-09-01

    Laser Induced Breakdown Spectroscopy (LIBS) is a well-known spectrochemical elemental analysis technique. In our investigations of the LIBS spectra it has been found that there is a remarkable correlation between the ionic to atomic spectral lines emission ratio and the surface hardness of eggshell for two Different Broiler Breeder at different age. The proposed technique has been applied successfully in poultry science to estimate the age of broiler breeders by measuring the surface hardness of their eggshell. The experiments have been performed on two different strains, Arbor Acres plus (AAP) and Hubard Classic (HC), and the results were satisfactory.

  3. Progress in fieldable laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Miziolek, Andrzej W.

    2012-06-01

    In recent years there has been great progress in the Laser Induced Breakdown Spectroscopy (LIBS) technology field. Significant advances have been made both in fundamental and applied research as well as in data processing/chemometrics. Improvements in components, most notably lasers/optics and spectrometers are enabling the development of new devices that are suitable for field use. These new commercial devices recently released to the marketplace, as well as ones currently under development, are bringing the potential of LIBS for CBRNE threat analysis into real-world applications.

  4. Computer methods for ITER-like materials LIBS diagnostics

    NASA Astrophysics Data System (ADS)

    Łepek, Michał; GÄ sior, Paweł

    2014-11-01

    Recent development of Laser-Induced Breakdown Spectroscopy (LIBS) caused that this method is considered as the most promising for future diagnostic applications for characterization of the deposited materials in the International Thermonuclear Experimental Reactor (ITER), which is currently under construction. In this article the basics of LIBS are shortly discussed and the software for spectra analyzing is presented. The main software function is to analyze measured spectra with respect to the certain element lines presence. Some program operation results are presented. Correct results for graphite and aluminum are obtained although identification of tungsten lines is a problem. The reason for this is low tungsten lines intensity, and thus low signal to noise ratio of the measured signal. In the second part artificial neural networks (ANNs) as the next step for LIBS spectra analyzing are proposed. The idea is focused on multilayer perceptron network (MLP) with backpropagation learning method. The potential of ANNs for data processing was proved through application in several LIBS-related domains, e.g. differentiating ancient Greek ceramics (discussed). The idea is to apply an ANN for determination of W, Al, C presence on ITER-like plasma-facing materials.

  5. LibQUAL+ and the Community College Library

    ERIC Educational Resources Information Center

    Johnson, Wendell G.

    2007-01-01

    Community colleges can use market surveys to better understand the delivery of library services from the standpoint of the end user. One such survey, LibQUAL+, measures library service in three dimensions: 1. Affect of Service (patron interaction with library staff); 2. Information Control (availability of needed resources and ease of accessing);…

  6. Library Users' Service Desires: A LibQUAL+ Study

    ERIC Educational Resources Information Center

    Thompson, Bruce; Kyrillidou, Martha; Cook, Colleen

    2008-01-01

    The present study was conducted to explore library users' desired service quality levels on the twenty-two core LibQUAL+ items. Specifically, we explored similarities and differences in users' desired library service quality levels across user groups (i.e., undergraduate students, graduate students, and faculty), across geographic locations (i.e.,…

  7. LIBSSIM: Simulation of LIBS Sampling on Rock Surfaces

    NASA Astrophysics Data System (ADS)

    Dobosh, P. A.; Breves, E. A.; Dyar, M. D.; McCanta, M.

    2012-03-01

    A Javascript-HTML5 model has been built to simulate LIBS sampling of a rock surface. The model allows construction of arbitrary rock slabs of chosen grain size and laser beam size (both in pixels) and reports mineral and oxide percentages.

  8. Preliminary fsLIBS study on bone tumors.

    PubMed

    Gill, Ruby K; Smith, Zachary J; Panchal, Ripul R; Bishop, John W; Gandour-Edwards, Regina; Wachsmann-Hogiu, Sebastian

    2015-12-01

    The aim of this study is to evaluate the capability of femtosecond Laser Induced Breakdown Spectroscopy (fsLIBS) to discriminate between normal and cancerous bone, with implications to femtosecond laser surgery procedures. The main advantage of using femtosecond lasers for surgery is that the same laser that is being used to ablate can also be used for a feedback system to prevent ablation of certain tissues. For bone tumor removal, this technique has the potential to reduce the number of repeat surgeries that currently must be performed due to incomplete removal of the tumor mass. In this paper, we performed fsLIBS on primary bone tumor, secondary tumor in bone, and normal bone. These tissues were excised from consenting patients and processed through the UC Davis Cancer Center Biorepository. For comparison, each tumor sample had a matched normal bone sample. fsLIBS was performed to characterize the spectral signatures of each tissue type. A minimum of 20 spectra were acquired for each sample. We did not detect significant differences between the fsLIBS spectra of secondary bone tumors and their matched normal bone samples, likely due to the heterogeneous nature of secondary bone tumors, with normal and cancerous tissue intermingling. However, we did observe an increase in the fsLIBS magnesium peak intensity relative to the calcium peak intensity for the primary bone tumor samples compared to the normal bone samples. These results show the potential of using femtosecond lasers for both ablation and a real-time feedback control system for treatment of primary bone tumors. PMID:26713199

  9. Preliminary fsLIBS study on bone tumors

    PubMed Central

    Gill, Ruby K.; Smith, Zachary J.; Panchal, Ripul R.; Bishop, John W.; Gandour-Edwards, Regina; Wachsmann-Hogiu, Sebastian

    2015-01-01

    The aim of this study is to evaluate the capability of femtosecond Laser Induced Breakdown Spectroscopy (fsLIBS) to discriminate between normal and cancerous bone, with implications to femtosecond laser surgery procedures. The main advantage of using femtosecond lasers for surgery is that the same laser that is being used to ablate can also be used for a feedback system to prevent ablation of certain tissues. For bone tumor removal, this technique has the potential to reduce the number of repeat surgeries that currently must be performed due to incomplete removal of the tumor mass. In this paper, we performed fsLIBS on primary bone tumor, secondary tumor in bone, and normal bone. These tissues were excised from consenting patients and processed through the UC Davis Cancer Center Biorepository. For comparison, each tumor sample had a matched normal bone sample. fsLIBS was performed to characterize the spectral signatures of each tissue type. A minimum of 20 spectra were acquired for each sample. We did not detect significant differences between the fsLIBS spectra of secondary bone tumors and their matched normal bone samples, likely due to the heterogeneous nature of secondary bone tumors, with normal and cancerous tissue intermingling. However, we did observe an increase in the fsLIBS magnesium peak intensity relative to the calcium peak intensity for the primary bone tumor samples compared to the normal bone samples. These results show the potential of using femtosecond lasers for both ablation and a real-time feedback control system for treatment of primary bone tumors. PMID:26713199

  10. Value Added?

    ERIC Educational Resources Information Center

    UCLA IDEA, 2012

    2012-01-01

    Value added measures (VAM) uses changes in student test scores to determine how much "value" an individual teacher has "added" to student growth during the school year. Some policymakers, school districts, and educational advocates have applauded VAM as a straightforward measure of teacher effectiveness: the better a teacher, the better students…

  11. Stoichiometry analysis of titanium oxide coating by LIBS

    NASA Astrophysics Data System (ADS)

    Estupiñán, H.; Peña, D. Y.; García, Y. O.; Cabanzo, R.; Mejía-Ospino, E.

    2009-05-01

    In this work, laser induced breakdown spectroscopy (LIBS) is used to determine the composition of titanium oxide film produced by anodized of Ti6Al4V alloy. We have used Ti lines in the spectral region between 470-520 nm to determine temperature of the plasma generated on anodized surface of Ti6Al4V alloy for temperature determination by Boltzmann plot method. In order to measure the content of oxygen and titanium ratio on the surface the alloy, we have used the oxygen lines 777.194, 777.417 and 777.539 nm, and titanium lines 780.597 and 782.491 nm observed in an ambient of argon. Finally, we report the possibilities for the determination of the coating chemical composition using LIBS.

  12. Optimized LWIR enhancement of nanosecond and femtosecond LIBS uranium emission

    NASA Astrophysics Data System (ADS)

    Akpovo, Codjo A.; Ford, Alan; Johnson, Lewis

    2016-05-01

    A carbon dioxide (CO2) transverse electrical breakdown in atmosphere (TEA), pulsed laser was used to enhance the laser-induced breakdown spectroscopy (LIBS) spectral signatures of uranium under nanosecond (ns) and femtosecond (fs) ablation. The peak areas of both ionic and neutral species increased by one order of magnitude for ns-ablation and two orders of magnitude for fs-ablation over LIBS when the CO2 TEA laser was used with samples of dried solutions of uranyl nitrate hexahydrate (UO2(NO3)2·6H2O) on silicon wafers. Electron temperature and density measurements show that the spectral emission improvement from using the TEA laser comes from plasma reheating.

  13. Preliminary LIBS analysis of Yucca Mountain manganese oxide minerals

    SciTech Connect

    Blacic, J.; Pettit, D.; Cremers, D.

    1996-01-01

    The licensing and performance of a potential repository at Yucca Mountain will require the characterization of radionuclide sorptive capacity of the host rock, which in turn calls for hundreds of analyses based on extensive sampling or in situ measurements. A rapid method specifically for characterizing the manganese oxide minerals occurring heterogeneously throughout the Yucca Mountain block as fracture surface coatings is needed. Our unique solution is a laser-induced breakdown spectroscopy (LIBS) surface-analysis technique that is usable in the field to produce high-resolution atomic emission spectra. In tests with manganese oxide minerals and fracture surface coatings from a few Yucca Mountain core samples, we used four spectral bands to show that qualitative measurement of all constituent elements except K and Na (in the presence of Mn) is possible with LIBS. Detailed calibration of final hardware will make the system quantitative.

  14. Characterization of Phyllosilicates by LIBS and Laser Raman Spectroscopy

    NASA Astrophysics Data System (ADS)

    Wang, A.; Sobron, P.

    2011-12-01

    NIR spectral signatures of phyllosilicates were recognized on Mars with wide distributions from orbit by OMEGA (on Mars Express orbiter) and CRISM (on Mars Reconnaissance Orbiter) observations. On the ground, geochemical and spectral features related to phyllosilicates were identified in rocks at two locations on Columbia Hill at Gusev crater using the data obtained by the Mars Exploration Rover (MER) Spirit. Furthermore, Opportunity rover is currently approaching the Cap of York at Endeavour crater on Meridiani Planum, where the signatures of phyllosilicates (and hydrous sulfates) were seen by CRISM. Laser-Induced Breakdown spectroscopy (LIBS) and Laser Raman spectroscopy will be used for the first time in rover missions in ChemCam on the NASA-MSL (Mars Science Laboratory) and in RLS on the ESA-ExoMars, respectively. As demonstrated by our previous studies, they are very powerful tools for characterizing the geochemistry and mineralogy aspects of the secondary minerals from aqueous alterations, especially hydrous sulfates. This study investigates the potential of LIBS and Raman spectroscopy for identifying and characterizing a variety of phyllosilicates, especially clays. Clay standards from the Clay Mineral Society were used. The LIBS measurements were made in a Planetary Environment and Analysis Chamber (PEACh) under Mars atmospheric pressure and composition, using 1064 nm as the excitation laser wavelength, same as ChemCam. The Raman measurements were made in ordinary laboratory environment using 532 nm as the excitation wavelength, same as RLS. The LIBS data were processed using custom automated software. We performed quantitative analysis of the spectra in order to evaluate the effectiveness of our method in: (a) discriminating between phyllosilicates and other silicates; (b) classifying different types of phyllosilicates (i.e., serpentine, chlorites, clays); and (c) correlating the LIBS-derived elemental abundances with the real chemical compositions of

  15. A hybrid calibration-free/artificial neural networks approach to the quantitative analysis of LIBS spectra

    NASA Astrophysics Data System (ADS)

    D'Andrea, Eleonora; Pagnotta, Stefano; Grifoni, Emanuela; Legnaioli, Stefano; Lorenzetti, Giulia; Palleschi, Vincenzo; Lazzerini, Beatrice

    2015-03-01

    A `hybrid' method is proposed for the quantitative analysis of materials by LIBS, combining the precision of the calibration-free LIBS (CF-LIBS) algorithm with the quickness of artificial neural networks. The method allows the precise determination of the samples' composition even in the presence of relatively large laser fluctuations and matrix effects. To show the strength and robustness of this approach, a number of synthetic LIBS spectra of Cu-Ni binary alloys with different composition were computer-simulated, in correspondence of different plasma temperatures, electron number densities and ablated mass. The CF-LIBS/ANN approach here proposed demonstrated to be capable, after appropriate training, of `learning' the basic physical relations between the experimentally measured line intensities and the plasma parameters. Because of that the composition of the sample can be correctly determined, as in CF-LIBS measurements, but in a much shorter time.

  16. Adding Value.

    ERIC Educational Resources Information Center

    Orsini, Larry L.; Hudack, Lawrence R.; Zekan, Donald L.

    1999-01-01

    The value-added statement (VAS), relatively unknown in the United States, is used in financial reports by many European companies. Saint Bonaventure University (New York) has adapted a VAS to make it appropriate for not-for-profit universities by identifying stakeholder groups (students, faculty, administrators/support personnel, creditors, the…

  17. Rethinking Responsible Literature Searching using LibGuides.

    PubMed

    Gerberi, Dana; Hawthorne, Dottie M; Larsen, Karen E

    2012-01-01

    Drawing from the Responsible Literature Searching project developed by the Health Sciences Library System-University of Pittsburgh, the Mayo Clinic Libraries utilized Springshare's LibGuides software to create an Effective Database Searching Guide for its diverse set of users. Library databases are organized under broad subject categories with overview information, links to help materials, and news on system updates. Additionally, the guide features a visual site map, searching best practices, a database comparison chart, responsible literature searching guidelines, classic evidence-based practice articles, and recommendations on when to contact a librarian for assistance. The self-guided tool is both easy to use and maintain. PMID:23092414

  18. Intermittent feeding in a migratory omnivore: Digestion and body composition of American Black Duck during autumn

    USGS Publications Warehouse

    Barboza, P.S.; Jorde, D.G.

    2001-01-01

    Birds fast intermittently during weather disturbances and migration. We tested responses of black duck to lost feeding days during autumn mass gain. Nine adult males were fed a pelleted diet (1.5% fat, 15.8% protein, and 18.3% neutral detergent fiber) and caged indoors during September and October (12 h light; 17? -24? C) to measure balances over 14 d when fed ad lib. each day and fasted intermittently for 2 d wk-1 (short fast) or 4 d wk-1 (long fast). Body mass (1,081 g), body water content, and metabolizable intakes of energy and protein were maintained as daily intakes of dry matter increased to 1.65 (short fast) and 2.35 (long fast) times the unfasted level. Intermittent feeding reduced metabolizability of dry matter, energy, protein, and acid detergent fiber. Concentrations of Mn provided similar estimates of metabolizability to direct measures in unfasted birds but underestimated measures of birds on long fasts. Fasting regimes continued outdoors for 9 wk when temperatures declined to -9? C. Birds on short fasts were heavier (1,373 vs. 1,241 g) and fatter (159 vs. 58 g) than those on long fasts, while body water (894 g) and protein (316 g) were similar between groups after 5 wk. Birds on long fasts subsequently gained mass when fed daily, but those on short fasts lost mass when fed each day. Omnivorous waterfowl combine ingestive and digestive flexibility with plasticity of body lipid to contend with uncertain food availability.

  19. DIS in AdS

    NASA Astrophysics Data System (ADS)

    Albacete, Javier L.; Kovchegov, Yuri V.; Taliotis, Anastasios

    2009-03-01

    We calculate the total cross section for the scattering of a quark-anti-quark dipole on a large nucleus at high energy for a strongly coupled N = 4 super Yang-Mills theory using AdS/CFT correspondence. We model the nucleus by a metric of a shock wave in AdS5. We then calculate the expectation value of the Wilson loop (the dipole) by finding the extrema of the Nambu-Goto action for an open string attached to the quark and antiquark lines of the loop in the background of an AdS5 shock wave. We find two physically meaningful extremal string configurations. For both solutions we obtain the forward scattering amplitude N for the quark dipole-nucleus scattering. We study the onset of unitarity with increasing center-of-mass energy and transverse size of the dipole: we observe that for both solutions the saturation scale Qs is independent of energy/Bjorken-x and depends on the atomic number of the nucleus as Qs˜A1/3. Finally we observe that while one of the solutions we found corresponds to the pomeron intercept of αP = 2 found earlier in the literature, when extended to higher energy or larger dipole sizes it violates the black disk limit. The other solution we found respects the black disk limit and yields the pomeron intercept of αP = 1.5. We thus conjecture that the right pomeron intercept in gauge theories at strong coupling may be αP = 1.5.

  20. Designing LibGuides as Instructional Tools for Critical Thinking and Effective Online Learning

    ERIC Educational Resources Information Center

    Baker, Ruth L.

    2014-01-01

    Did you ever wish for an easy-to-maintain tool to create course-level or assignment-level instruction for online or distance students? LibGuides can provide the solution! LibGuides provide a versatile and easy-to-maintain platform for delivering step-by-step, scaffolded tutorials that enhance learning outcomes through chunking, reduced strain on…

  1. Structure of Perceptions of Service Quality in Libraries: A LibQUAL+ Study.

    ERIC Educational Resources Information Center

    Thompson, Bruce; Cook, Colleen; Heath, Fred

    2003-01-01

    Used confirmatory factor analysis to evaluate the score integrity of LibQUALl+, an instrument to measure perceptions of library service quality. Results for 60,027 graduate and undergraduate students suggest that the model implied by LibQUAL is reasonable and invariant across independent samples and fits all three major subgroups of library users.…

  2. Does LibQUAL+[TM] Account for Student Loyalty to a University College Library?

    ERIC Educational Resources Information Center

    Helgesen, Oyvind; Nesset, Erik

    2011-01-01

    Purpose: The purpose of this paper is to find out whether LibQUAL+[TM]can account for student loyalty to the library of an institution of higher education. LibQUAL+[TM] is a marketing tool that is used to measure perceived service quality of libraries, and the present analysis aims at validating this service quality instrument within a more…

  3. LibRef-L: Sharing Reference Expertise over the Academic Networks.

    ERIC Educational Resources Information Center

    Robinson, Kara; Kovacs, Diane

    1993-01-01

    Describes LibRef-L, an electronic mail-based conference that was developed to provide a forum for the discussion of library reference service issues. Networks and electronic mail are described; a profile of subscribers is given; and how to subscribe to LibRef-L is explained. (two references) (LRW)

  4. The effect of nutrient media water purity on LIBS based identification of bacteria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Single pulse laser induced breakdown spectroscopy (LIBS) is used as the basis for discrimination between 3 genera of Gram-negative bacteria and 2 genera of gram-positive bacteria representing pathogenic threats commonly found in poultry processing rinse waters. Because LIBS-based discrimination reli...

  5. New Library, New Librarian, New Student: Using LibGuides to Reach the Virtual Student

    ERIC Educational Resources Information Center

    Roberts, Sara; Hunter, Dwight

    2011-01-01

    This article examines the virtual pathfinder and its relationship with distance education students. Various topics are addressed in relation to virtual students, LibGuides and collaborative efforts between librarians and teaching faculty. A brief history of the subject guide is presented, advantages and disadvantages of LibGuides are discussed and…

  6. Synthesis of a predicted layered LiB via cold compression

    NASA Astrophysics Data System (ADS)

    Kolmogorov, A. N.; Hajinazar, S.; Angyal, C.; Kuznetsov, V. L.; Jephcoat, A. P.

    2015-10-01

    We have discovered stoichiometric LiB with hexagonal boron layers by compressing known LiB0.9 with linear boron chains. The s p to s p2 rebonding occurred at room temperature and pressures above 21 GPa. The study was motivated by a long-standing prediction that LiB in the stable layered configuration could be a close analog to the MgB2 superconductor. Apparent stacking disorder in LiB and a stoichiometry shift in LiBy (down to y ≈0.75 ) made material characterization a challenge. Ab initio modeling allowed us to establish the pressure-dependent composition of LiBy and predict related stable structures overlooked in previous studies. Synchrotron powder diffraction data on quenched samples in the diamond anvil cell indicate that LiB remains metastable at ambient pressure.

  7. Microanalysis of Multi-Element in Juncus effusus L. by LIBS Technique

    NASA Astrophysics Data System (ADS)

    Liu, Xiaona; Huang, Jianmei; Wu, Zhisheng; Zhang, Qiao; Shi, Xinyuan; Zhao, Na; Jia, Shuaiyun; Qiao, Yanjiang

    2015-11-01

    Laser-induced breakdown spectroscopy (LIBS) was used to decipher the unique multi-elemental characteristics of Juncus effusus L. The spectral fingerprints of Juncus effusus L. were established based on elemental microanalysis via LIBS. Microanalysis and multimode sampling methodologies were designed in this study. The relative standard deviation (RSD) approach was performed to optimize the multi-shot measurements. Taking advantage of the capability with no or minimal sample pre-treatment of LIBS, a thermodynamic chart of four elements (Mg, Ca, Ba, and Na) was created from twelve collection regions. The diagram of elemental distribution on a micro-scale was generated to explore the nature of Juncus effusus L. by LIBS. The results demonstrated that LIBS is a promising technique for rapid elemental microanalysis of heterogeneous samples. supported by National Natural Science Foundation of China (No. 81303218), Beijing Municipal Government for the University Affiliated with the Party Central Committee, and Doctoral Fund of Ministry of Education of China (No. 20130013120006)

  8. Xanthophylls in Poultry Feeding

    NASA Astrophysics Data System (ADS)

    Breithaupt, Diemar R.

    Since most consumers associate an intense colour of food with healthy animals and high food quality, xanthophylls are widely used as feed additives to generate products that meet consumers' demands. An important large-scale application is in poultry farming, where xanthophylls are added to feed to give the golden colour of egg yolk that is so much appreciated. Now, with numerous new applications in human food, in the pharmaceutical industry, and in cosmetic products, there is an increasing demand for xanthophylls on the international market (Volume 5, Chapter 4).

  9. The effect of the laser wavelength on collinear double pulse laser induced breakdown spectroscopy (DP-LIBS)

    NASA Astrophysics Data System (ADS)

    Wang, Qi; Lin, Yanqing; Liu, Jing; Fan, Shuang; Xu, Zhuopin; Huang, Qing; Wu, Yuejin

    2016-05-01

    The pulsed lasers at wavelengths of 532 nm and 1064 nm were used as two beams of light for collinear double pulse laser induced breakdown spectroscopy (DP-LIBS). By changing the time sequence of two beams of different lasers, we studied the effect of the interval of two pulses of DP-LIBS on spectral signals compared with single pulsed (SP) LIBS.

  10. A Simple LIBS (Laser-Induced Breakdown Spectroscopy) Laboratory Experiment to Introduce Undergraduates to Calibration Functions and Atomic Spectroscopy

    ERIC Educational Resources Information Center

    Chinni, Rosemarie C.

    2012-01-01

    This laboratory experiment introduces students to a different type of atomic spectroscopy: laser-induced breakdown spectroscopy (LIBS). LIBS uses a laser-generated spark to excite the sample; once excited, the elemental emission is spectrally resolved and detected. The students use LIBS to analyze a series of standard synthetic silicate samples…

  11. DIS in AdS

    SciTech Connect

    Albacete, Javier L.; Kovchegov, Yuri V.; Taliotis, Anastasios

    2009-03-23

    We calculate the total cross section for the scattering of a quark-anti-quark dipole on a large nucleus at high energy for a strongly coupled N = 4 super Yang-Mills theory using AdS/CFT correspondence. We model the nucleus by a metric of a shock wave in AdS{sub 5}. We then calculate the expectation value of the Wilson loop (the dipole) by finding the extrema of the Nambu-Goto action for an open string attached to the quark and antiquark lines of the loop in the background of an AdS{sub 5} shock wave. We find two physically meaningful extremal string configurations. For both solutions we obtain the forward scattering amplitude N for the quark dipole-nucleus scattering. We study the onset of unitarity with increasing center-of-mass energy and transverse size of the dipole: we observe that for both solutions the saturation scale Q{sub s} is independent of energy/Bjorken-x and depends on the atomic number of the nucleus as Q{sub s}{approx}A{sup 1/3}. Finally we observe that while one of the solutions we found corresponds to the pomeron intercept of {alpha}{sub P} = 2 found earlier in the literature, when extended to higher energy or larger dipole sizes it violates the black disk limit. The other solution we found respects the black disk limit and yields the pomeron intercept of {alpha}{sub P} = 1.5. We thus conjecture that the right pomeron intercept in gauge theories at strong coupling may be {alpha}{sub P} = 1.5.

  12. Bubbling AdS3

    NASA Astrophysics Data System (ADS)

    Martelli, Dario; Morales, Jose F.

    2005-02-01

    In the light of the recent Lin, Lunin, Maldacena (LLM) results, we investigate 1/2-BPS geometries in minimal (and next to minimal) supergravity in D = 6 dimensions. In the case of minimal supergravity, solutions are given by fibrations of a two-torus T2 specified by two harmonic functions. For a rectangular torus the two functions are related by a non-linear equation with rare solutions: AdS3 × S3, the pp-wave and the multi-center string. ``Bubbling'', i.e. superpositions of droplets, is accommodated by allowing the complex structure of the T2 to vary over the base. The analysis is repeated in the presence of a tensor multiplet and similar conclusions are reached, with generic solutions describing D1D5 (or their dual fundamental string-momentum) systems. In this framework, the profile of the dual fundamental string-momentum system is identified with the boundaries of the droplets in a two-dimensional plane.

  13. Enhancement of LIBS emission using antenna-coupled microwave.

    PubMed

    Khumaeni, Ali; Motonobu, Tampo; Katsuaki, Akaoka; Masabumi, Miyabe; Ikuo, Wakaida

    2013-12-01

    Intensified microwave coupled by a loop antenna (diameter of 3 mm) has been employed to enhance the laser-induced breakdown spectroscopy (LIBS) emission. In this method, a laser plasma was induced on Gd₂O₃ sample at a reduced pressure by focusing a pulsed Nd:YAG laser (532 nm, 10 ns, 5 mJ) at a local point, at which electromagnetic field was produced by introducing microwave radiation using loop antenna. The plasma emission was significantly enhanced by absorbing the microwave radiation, resulting in high-temperature plasma and long-lifetime plasma emission. By using this method, the enhancement of Gd lines was up to 32 times, depending upon the emission lines observed. A linear calibration curve of Ca contained in the Gd₂O₃ sample was made. The detection limit of Ca was approximately 2 mg/kg. This present method is very useful for identification of trace elements in nuclear fuel and radioactive materials. PMID:24514526

  14. libMSR library and msr-safe kernel module

    SciTech Connect

    2013-09-26

    Modern processors offer a wide range of control and measurement features. While those are traditionally accessed through libraries like PAPI, some newer features no longer follow the traditional model of counters that can be used to only read the state of the processor. For example, Precise Event Based Sampling (PEBS) can generate records that requires a kernel memory for storage. Additionally, new features like power capping and thermal control require similar new access methods. All of these features are ultimately controlled through Model Specific Registers (MSRs). We therefore need new mechanisms to make such features available to tools and ultimately to the user. libMSR provides a convenient interface to access MSRs and to allow tools to utilize their full functionality.

  15. libMSR library and msr-safe kernel module

    2013-09-26

    Modern processors offer a wide range of control and measurement features. While those are traditionally accessed through libraries like PAPI, some newer features no longer follow the traditional model of counters that can be used to only read the state of the processor. For example, Precise Event Based Sampling (PEBS) can generate records that requires a kernel memory for storage. Additionally, new features like power capping and thermal control require similar new access methods. Allmore » of these features are ultimately controlled through Model Specific Registers (MSRs). We therefore need new mechanisms to make such features available to tools and ultimately to the user. libMSR provides a convenient interface to access MSRs and to allow tools to utilize their full functionality.« less

  16. The Low-Lying Electronic States of LiB

    NASA Technical Reports Server (NTRS)

    Ricca, Alessandra; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R. (Technical Monitor)

    1995-01-01

    The spectroscopic constants for the triplet and singlet states of LiB below about 30 000/ cm are determined using an internally contracted multireference configuration interaction approach in conjunction with [6s 5p 3d 2f] atomic natural orbital basis sets. The ground state is (sup 3)Pi as found in previous work. No excited triplet states are found to be ideal for characterizing the ground state; the (1)(sup 3)Sigma(sup -) state has a transition energy that is too small for many experimental approaches and the (2)(sup 3)Pi and (3)(sup 3)Pi states have bond lengths that are significantly longer than the ground state, resulting in transition intensities that are spread out over many vibrational levels of the ground state.

  17. ZioLib: A parallel I/O library

    SciTech Connect

    Yang, Woo-Sun; Ding, Chris

    2003-08-01

    In a distributed memory parallel environment, many applications rely on a serial I/O strategy, where the global array is gathered on a single MPI process and then written out to a file. I/O performance with this approach is largely limited by single process I/O bandwidth. Even when parallel I/O is used, satisfactory parallel scaling is not always observed. It is because in many applications fields are not necessarily in a most favorable parallel decomposition for I/O. The best I/O rates are obtained when a field is decomposed with respect to the array's last dimension (referred to here as Z). Another situation often encountered in many applications is that a field in CPU resident memory is in one index order but must be stored in a disk file in another order. Changing index orders can complicate a parallel I/O implementation and slow down I/O. ZioLib facilitates an efficient parallel I/O for arrays in such situations. In case of a write, ZioLib remaps a distributed field into a Z-decomposition on a subset of processes (which will be called the I/O staging processes) and from there writes to a disk file in parallel. In this Z-decomposition, the data layout of the remapped array on the staging processes memory is the same as on disk, thus only block data transfer occurs during parallel I/O, achieving maximum efficiency. In case of a read the steps are reversed to build the required distributed arrays on the computational processes.

  18. LIBS for tokamak plasma facing components characterisation: Perspectives on in situ tritium cartography

    NASA Astrophysics Data System (ADS)

    Semerok, A.; Grisolia, C.

    2013-08-01

    Feasibility of in situ LIBS remote measurements with the plasma facing components (PFCs) from the European tokamaks (TORE SUPRA, CEA Cadarache, France and TEXTOR, Julich, Germany) has been studied in laboratory using Q-switched nanosecond Nd-YAG lasers. LIBS particular properties and optimal parameters were determined for in-depth PFCs characterisation. The LIBS method was in situ tested on the Joint European Torus (JET) in the UK with the EDGE LIDAR Laser System (Ruby laser, 3 J, 690 nm wavelength, 300 ps pulse duration, intensity up to 70 GW/cm2). Several analytical spectral lines of H, CII, CrI, and BeII in plasma were observed and identified in 400-600 nm spectral range with the optimised LIBS and detection system. The LIBS in-depth cartography is in agreement with the surface properties of the tile under analysis, thus confirming feasibility of in situ LIBS. Further LIBS technique improvements required to provide tritium concentration measurements more accurately are discussed.

  19. LIBS analysis of geological samples at low pressures : application to Mars, the Moon, and asteroids

    SciTech Connect

    Cremers, D. A.; Sevostiyanova, E. V.; Gibson, L. E.; Wiens, R. C.

    2004-01-01

    Recently, LIBS (Laser-Induced Breakdown Spectroscopy) has been proposed as a new method for elemental analysis in space exploration with Mars specifically targeted. there are many reasons for this including rapid analysis (< 2 min.), in-situ and stand-off analysis (< 20 meters) capability, and the ability to readily combine LIBS with other spectroscopic methods (Raman, fluorescence) that provide data complementary to LIBS. In comparison with past and current elemental analysis methods used on planetary surfaces, these capabilities of LIBS should greatly increase the scientific return from future missions. They are characterizing the LIBS method for space exploration applications with emphasis on analysis at reduced pressures ({approx} 7 Torr CO{sub 2} for Mars) and near vacuum (50 mTorr for asteroids and the Moon; at pressures below about 50 mTorr no significant changes in the plasma are observed). This characterization is important because the excitation properties of the LIBS plasma are strongly dependent on pressure of the surrounding atmosphere. Topics addressed include: (1) calibration curves and detection limits for major and minor elements of interest to geochemistry at the two lower pressures as well as atmospheric pressure (for comparison), (2) using short (<22 cm for in-situ) and medium length (4 m for stand-off) light paths for analysis, and (3) characterization of the LIBS plasma at different pressures.

  20. Effects of segregation and impact of specific feeding behaviour and additional fruit on voluntary nutrient and energy intake in yellow-shouldered amazons (Amazona barbadensis) when fed a multi-component seed diet ad libitum.

    PubMed

    Kalmar, I D; Veys, A C; Geeroms, B; Reinschmidt, M; Waugh, D; Werquin, G; Janssens, G P J

    2010-12-01

    Parrots are commonly fed multi-component seed diets; however, both segregation and feeding behaviour might alter ingredient and nutrient composition of the offered diet. First, the nutritional impact of segregation was assessed as it occurs when multi-component diets are temporarily stored in food containers that are replenished before completely emptied and birds being fed from the upper layer. The most detrimental effect hereof was a vast decrease in mineral supplements, leading to a decrease in Ca:P ratio in the offered food in relation to the formulated diet. Next, caloric distribution shifted towards more EE energy at the expense of NFE energy, as proportion of oilseeds increased and NFE-rich seeds decreased. Next, a feeding trial was performed on six yellow-shouldered amazons (Amazona Barbadensis) in which nutritional impact of parrot-specific feeding behaviour was assessed as well as the influence of additional provision of fruit next to the seed mixture. Profound selective feeding behaviour and dehusking of seeds resulted in a vast increase in energetic density by up to 64% in the ingested fraction in relation to the offered mixture in toto. Furthermore, the already suboptimal Ca:P ratio further deteriorated and caloric distribution shifted by over twofold towards EE energy accompanied with a vast decline in NFE energy, CP energy remaining similar. Finally, provision of fruit next to the seed diet significantly lowered voluntary energy intake from 936 ± 71 to 809 ± 109 kJ ME/kg(0.75)/day, without compromising adequate protein intake. In conclusion, notwithstanding efforts of nutritionists to formulate diets to approximate estimated, species-specific requirements, nutritional composition of the actually consumed fraction of multi-component seed diets can be vastly deteriorated by both animal and management factors. Furthermore, offering of fruit next to a seed-based diet effectively reduces voluntary energy intake and can hence be applied to abate obesity

  1. Remote Laser Induced Breakdown Spectroscopy (LIBS) Geochemical Investigation under Venus Atmospheric Conditions

    NASA Astrophysics Data System (ADS)

    Clegg, S. M.; Barefield, J. E.; Humphries, S.; Wiens, R. C.; Vaniman, D.; Dyar, M. D.; Tucker, J. M.; Sharma, S. K.; Misra, A. K.

    2009-12-01

    The extreme Venus surface temperature (740 K) and atmospheric pressure (93 atm) creates a challenging environment for future lander missions. Scientific investigations capable of Venus geochemical observations must be completed within several hours of landing before the lander is overcome by the harsh atmosphere. A combined remote Raman - LIBS (Laser Induced Breakdown Spectroscopy) instrument is capable of accomplishing geochemical science goals without the risks associated with collecting samples and bringing them into the lander. Wiens et al. [1] and Sharma et al. [2] have demonstrated that both analytical techniques can be integrated into a single instrument capable of planetary missions. The focus of this paper is to explore the capability to probe geologic samples with LIBS and demonstrate the quantitative analysis under Venus surface conditions. The LIBS experiment involves focusing a Nd:YAG laser operating at 1064 nm onto the surface of the sample. The laser ablates material from the surface, generating a plasma containing electronically excited atoms, ions and small molecules. Some of this emission is collected with an 89 mm diameter telescope. The light is directed into a Princeton Instruments f/4 0.25 m dispersive spectrometer and recorded with an ICCD detector. The powdered and pelletized samples are placed in a pressure vessel containing supercritical CO2 at 93 atm and at least 423 K and the vessel is placed at least 1.6 m from the telescope and laser. A range of Venus-analog basaltic rock types [3] was chosen for this study to reproduce compositions identified by Soviet Venera and VEGA landers, including several standards: four basalts (BCR-2, BIR-1, GUWBM, JB-2), granite (GBW 07015), andesite (JA-1), carbonate (SARM-40), and Kauai volcanic (KV04-17, KV04-25). We also added a good Venus analog, TAP 04, which is an alkali-rich rock from an olivine minette in the Ayutla volcanic field (Righter and Rosas-Elguera [4]). Our goal was to study samples with a

  2. Measuring H, O, li, B, and BE on Planetary Surfaces: Calibration of Laser-Induced Breakdown Spectroscopy (libs) Data Under Air, Vacuum, and CO2

    NASA Astrophysics Data System (ADS)

    Dyar, M. D.; Nelms, M.; Breves, E. A.

    2012-12-01

    other light elements are directly measured are nearly nonexistent in the 1-2 g quantities needed for LIBS analyses. For this study, we have obtained two sample suites that provide calibrations needed for accurate analyses of H, O, B, Be, and Li in geological samples. The first suite of 11 samples was analyzed for oxygen by fast neutron activation analysis. The second suite includes 11 gem-quality minerals representing the major rock-forming species for B, Li, and Be-rich parageneses. Light elements were directly analyzed using a combination of EMPA, XRF, ion microprobe, uranium extraction, proton-induced gamma-ray emission (PIGE), and prompt gamma-ray neutron activation analysis (PGNAA). LIBS spectra were acquired at Mount Holyoke College under air, vacuum, and CO2 to simulate terrestrial, lunar, and martian environments. Spectra were then used to develop three separate calibration models (one for each environment), enabling LIBS characterization of light elements using multivariate analyses. Results show that when direct analyses of H, O, Li, B, and Be are used rather than LOI results, inferred, or indirectly calculated values, optimal root mean squared errors of prediction result. We are actively adding samples to these calibration suites, and we expect that prediction errors (accuracies) of <1wt% for these elements are possible.

  3. Feeding Tubes

    MedlinePlus

    ... administer the TPN. Tubes Used for Enteral Feeds NG (Nasogastric Tube) A flexible tube is placed via ... down through the esophagus into the stomach. The NG tube can be used to empty the stomach ...

  4. Raman and Laser-Induced Breakdown Spectroscopy (LIBS) Remote Geochemical Analysis Under Venus Atmospheric Pressure

    NASA Astrophysics Data System (ADS)

    Clegg, S.; Sharma, S. K.; Misra, A. K.; Dyar, M. D.; Dallmann, N.; Wiens, R. C.; Vaniman, D. T.; Speicher, E. A.; Smrekar, S. E.; Wang, A.; Maurice, S.; Esposito, L.

    2012-03-01

    A remote Raman-LIBS spectrometer (RLS) is a rapid method to determine Venus surface chemistry and mineralogy without collecting samples and bringing them into the lander. The RLS results from 18 synthetic samples will be presented.

  5. HSCL LibQUAL+ 2004: from numbers and graphs to practical application.

    PubMed

    Foss, Michelle M; Buhler, Amy; Rhine, Lenny; Layton, Beth

    2006-01-01

    The University of Florida Health Science Center Libraries created a task force representing various departments to review data from its 2004 LibQUAL+ survey. This review compared results from the 2002 and 2004 LibQUAL+ surveys, and the data from the Association of Academic Health Science Libraries 2004 cohort. The task force analyzed the key components of the LibQUAL+ survey: Affect of Service, Information Control, Library as Place, and user comments. At the conclusion of this review, the task force made recommendations and suggestions along departmental lines to meet the patrons' needs and expectations. In addition to following the task force recommendations, the Libraries independently implemented several new services and hired additional personnel after the completion of the 2004 survey. Combined, these changes should improve overall library service and increase customer satisfaction. Looking towards the 2006 LibQUAL+ survey, the task force will be convened in advance and will guide the entire process. PMID:16635953

  6. Multivariate analysis of remote LIBS spectra using partial least squares, principal component analysis, and related techniques

    SciTech Connect

    Clegg, Samuel M; Barefield, James E; Wiens, Roger C; Sklute, Elizabeth; Dyare, Melinda D

    2008-01-01

    Quantitative analysis with LIBS traditionally employs calibration curves that are complicated by the chemical matrix effects. These chemical matrix effects influence the LIBS plasma and the ratio of elemental composition to elemental emission line intensity. Consequently, LIBS calibration typically requires a priori knowledge of the unknown, in order for a series of calibration standards similar to the unknown to be employed. In this paper, three new Multivariate Analysis (MV A) techniques are employed to analyze the LIBS spectra of 18 disparate igneous and highly-metamorphosed rock samples. Partial Least Squares (PLS) analysis is used to generate a calibration model from which unknown samples can be analyzed. Principal Components Analysis (PCA) and Soft Independent Modeling of Class Analogy (SIMCA) are employed to generate a model and predict the rock type of the samples. These MV A techniques appear to exploit the matrix effects associated with the chemistries of these 18 samples.

  7. Constrained-transport Hall-MHD simulations using CWENO reconstruction with libMRC

    NASA Astrophysics Data System (ADS)

    Lin, Liwei; Germaschewski, Kai; Abbott, Stephen; Maynard, Kris; Raeder, Jimmy

    2013-10-01

    We present a new CWENO (Centrally-Weighted Essentially Non-Oscillatory) reconstruction based extended MHD (XMHD) solver that has been built for libMRC. libMRC is a library for creating efficient parallel PDE solvers on structured grids, which is used in the MRC (Magnetic Reconnection Code), OpenGGCM (Open Global Geospace Circulation Model) and PSC (Plasma Simulation Code) codes. The use of libMRC gives us access to its core functionality of providing an automated code generation framework which takes a user provided PDE right hand side in symbolic form to generate an efficient, computer-architecture specific, parallel code. libMRC also supports block-structured adaptive mesh refinement, and implicit-time stepping through integration with the PETSc library. We demonstrate validation of the new CWENO MHD solver against existing solvers both in standard test problems as well as in 3D global magnetosphere simulations.

  8. Laser-induced breakdown spectroscopy (LIBS): An innovative tool for studying bacteria

    NASA Astrophysics Data System (ADS)

    Mohaidat, Qassem I.

    Laser-induced breakdown spectroscopy (LIBS) has gained a reputation as a flexible and convenient technique for rapidly determining the elemental composition of samples with minimal or no sample preparation. In this dissertation, I will describe the benefits of using LIBS for the rapid discrimination and identification of bacteria (both pathogenic and non-pathogenic) based on the relative concentration of trace inorganic elements such as Mg, P, Ca, and Na. The speed, portability, and robustness of the technique suggest that LIBS may be applicable as a rapid point-of-care medical diagnostic technology. LIBS spectra of multiple genera of bacteria such as Escherichia, Streptococcus, Mycobacterium, and Staphylococcus were acquired and successfully analyzed using a computerized discriminant function analysis (DFA). It was shown that a LIBS-based bacterial identification might be insensitive to a wide range of biological changes that could occur in the bacterial cell due to a variety of environmental stresses that the cell may encounter. The effect of reducing the number of bacterial cells on the LIBS-based classification was also studied. These results showed that with 2500 bacteria, the identification of bacterial specimens was still possible. Importantly, it was shown that bacteria in mixed samples (more than one type of bacteria being present) were identifiable. The dominant or majority component of a two-component mixture was reliably identified as long as it comprised 70% of the mixture or more. Finally, to simulate a clinical specimen in a precursor to actual clinical tests, Staphylococcus epidermidis bacteria were collected from urine samples (to simulate a urinary tract infection specimen) and were tested via LIBS without washing. The analysis showed that these bacteria possessed exactly the same spectral fingerprint as control bacteria obtained from sterile deionized water, resulting in a 100% correct classification. This indicates that the presence of other

  9. Eye-safe infrared laser-induced breakdown spectroscopy (LIBS) emissions from energetic materials

    NASA Astrophysics Data System (ADS)

    Brown, Ei E.; Hömmerich, Uwe; Yang, Clayton C.; Jin, Feng; Trivedi, Sudhir B.; Samuels, Alan C.

    2016-05-01

    Laser-induced breakdown spectroscopy is a powerful diagnostic tool for detection of trace elements by monitoring the atomic and ionic emission from laser-induced plasmas. Besides elemental emissions from conventional UV-Vis LIBS, molecular LIBS emission signatures of the target compounds were observed in the long-wave infrared (LWIR) region in recent studies. Most current LIBS studies employ the fundamental Nd:YAG laser output at 1.064 μm, which has extremely low eye-damage threshold. In this work, comparative LWIR-LIBS emissions studies using traditional 1.064 μm pumping and eye-safe laser wavelength at 1.574 μm were performed on several energetic materials for applications in chemical, biological, and explosive (CBE) sensing. A Q-switched Nd: YAG laser operating at 1.064 μm and the 1.574 μm output of a pulsed Nd:YAG pumped Optical Parametric Oscillator were employed as the excitation sources. The investigated energetic materials were studied for the appearance of LWIR-LIBS emissions (4-12 μm) that are directly indicative of oxygenated breakdown products as well as partially dissociated and recombination molecular species. The observed molecular IR LIBS emission bands showed strong correlation with FTIR absorption spectra of the studied materials for 1.064 μm and 1.574 μm pump wavelengths.

  10. Study of archaeological coins of different dynasties using libs coupled with multivariate analysis

    NASA Astrophysics Data System (ADS)

    Awasthi, Shikha; Kumar, Rohit; Rai, G. K.; Rai, A. K.

    2016-04-01

    Laser Induced Breakdown Spectroscopy (LIBS) is an atomic emission spectroscopic technique having unique capability of an in-situ monitoring tool for detection and quantification of elements present in different artifacts. Archaeological coins collected form G.R. Sharma Memorial Museum; University of Allahabad, India has been analyzed using LIBS technique. These coins were obtained from excavation of Kausambi, Uttar Pradesh, India. LIBS system assembled in the laboratory (laser Nd:YAG 532 nm, 4 ns pulse width FWHM with Ocean Optics LIBS 2000+ spectrometer) is employed for spectral acquisition. The spectral lines of Ag, Cu, Ca, Sn, Si, Fe and Mg are identified in the LIBS spectra of different coins. LIBS along with Multivariate Analysis play an effective role for classification and contribution of spectral lines in different coins. The discrimination between five coins with Archaeological interest has been carried out using Principal Component Analysis (PCA). The results show the potential relevancy of the methodology used in the elemental identification and classification of artifacts with high accuracy and robustness.

  11. Clogging of feeding tubes.

    PubMed

    Marcuard, S P; Perkins, A M

    1988-01-01

    This is a report of an in vitro study evaluating clotting ability of some formulas with intact protein and hydrolyzed protein sources in a series of buffers ranging from a pH of 1 thru 10. The following 10 products were tested: Ensure Plus, Ensure, Enrich, Osmolite, Pulmocare, Citrotein, Resource, Vivonex TEN, Vital, and Hepatic Acid II. Protein (10 and 20 g/liter) was added to Citrotein and Ensure Plus. All formulas were tested at full and some at half strength. Clotting occurred only in premixed intact protein formulas (Pulmocare, Ensure Plus, Osmolite, Enrich, Ensure) and in Resource. No clotting was observed for Citrotein (intact protein formula in powder form), Vital, Vivonex TEN, and Hepatic Aid II. Adding protein did not cause or increase clotting. In summary, clotting of some liquid formula diet appears to be an important factor causing possible gastric feeding tube occlusion. The following measures may help in preventing this problem: flushing before and after aspirating for gastric residuals to eliminate acid precipitation of formula in the feeding tube, advance the nasogastric feeding tube into the duodenum if possible, and avoid mixing these products with liquid medications having a pH value of 5.0 or less. PMID:3138452

  12. Feeding guilt.

    PubMed

    Byrom, Anna

    2013-03-01

    Breastfeeding is increasingly equated to ideologies of the 'good mother' in our society in response to a growing body of evidence identifying its benefits. Women who choose not to or are unable to breastfeed can experience a sense of guilt in response to cultural expectations that 'breast is best'. These negative feelings can impact upon their adaptation to and enjoyment of motherhood. This discussion paper examines the experience of maternal guilt with specific reference to infant feeding. An exploration of the reasons mothers may feel guilty about their feeding experiences is offered. Finally some suggestions are made about how midwives and breastfeeding advocates might improve care for mothers' emotional wellbeing. PMID:23590082

  13. Performance evaluation of Laser Induced Breakdown Spectroscopy (LIBS) for quantitative analysis of rare earth elements in phosphate glasses

    NASA Astrophysics Data System (ADS)

    Devangad, Praveen; Unnikrishnan, V. K.; Nayak, Rajesh; Tamboli, M. M.; Muhammed Shameem, K. M.; Santhosh, C.; Kumar, G. A.; Sardar, D. K.

    2016-02-01

    In the current study, we have determined the elemental compositions of synthesized rare earth doped phosphate glasses using a laboratory Laser-Induced Breakdown Spectroscopy (LIBS) system. LIBS spectra of this rare earth (samarium (Sm), thulium (Tm) and ytterbium (Yb)) doped glass samples with known composition are recorded using a highly sensitive detector. Major atomic emission lines of Sm, Tm and Yb found in LIBS spectra are reported. By considering the atomic emission line of phosphorous as an internal standard, calibration curves were constructed for all the rare earth concentrations. Very good linear regression coefficient (R2) values were obtained using this technique. Analytical predictive skill of LIBS was studied further using leave-one-out method. Low values of the reported correlation uncertainty between measured LIBS concentration ratio and certified concentration ratio confirms that LIBS technique has great potential for quantitative analysis of rare earth elements in glass matrix.

  14. Quantitative Analysis of Heavy Metals in Water Based on LIBS with an Automatic Device for Sample Preparation

    NASA Astrophysics Data System (ADS)

    Hu, Li; Zhao, Nanjing; Liu, Wenqing; Meng, Deshuo; Fang, Li; Wang, Yin; Yu, Yang; Ma, Mingjun

    2015-08-01

    Heavy metals in water can be deposited on graphite flakes, which can be used as an enrichment method for laser-induced breakdown spectroscopy (LIBS) and is studied in this paper. The graphite samples were prepared with an automatic device, which was composed of a loading and unloading module, a quantitatively adding solution module, a rapid heating and drying module and a precise rotating module. The experimental results showed that the sample preparation methods had no significant effect on sample distribution and the LIBS signal accumulated in 20 pulses was stable and repeatable. With an increasing amount of the sample solution on the graphite flake, the peak intensity at Cu I 324.75 nm accorded with the exponential function with a correlation coefficient of 0.9963 and the background intensity remained unchanged. The limit of detection (LOD) was calculated through linear fitting of the peak intensity versus the concentration. The LOD decreased rapidly with an increasing amount of sample solution until the amount exceeded 20 mL and the correlation coefficient of exponential function fitting was 0.991. The LOD of Pb, Ni, Cd, Cr and Zn after evaporating different amounts of sample solution on the graphite flakes was measured and the variation tendency of their LOD with sample solution amounts was similar to the tendency for Cu. The experimental data and conclusions could provide a reference for automatic sample preparation and heavy metal in situ detection. supported by National Natural Science Foundation of China (No. 60908018), National High Technology Research and Development Program of China (No. 2013AA065502) and Anhui Province Outstanding Youth Science Fund of China (No. 1108085J19)

  15. Chemical etching method assisted double-pulse LIBS for the analysis of silicon crystals

    NASA Astrophysics Data System (ADS)

    Khalil, A. A. I.

    2015-06-01

    Two Nd:YAG lasers working in pulsed modes are combined in the same direction (collinear arrangement) to focus on silicon (Si) crystals in reduced oxygen atmosphere (0.1 mbar) for double-pulse laser-induced breakdown spectroscopy (DP-LIBS) system. Silicon crystals of (100) and (111) orientations were investigated, and Si samples were measured either without prior treatment ("untreated") or after fabrication of nano-pores ("treated"). Nano-pores are produced by metal coating and by chemical etching. DP-LIBS spectra were compared for different Si samples (untreated, treated, (100) and (111) orientations), for double-pulse (DP) (with 266 nm pulse followed by 1064 nm pulse) excitation and for different delay times (times between the excitation laser pulse and the detection ICCD gate); treatment by chemical etching has been studied as well. The intensity of the atomic line Si I at 288.16 nm was enhanced by a factor of about three by using the DP-LIBS signals as compared to the single-pulse (SP) signal which could increase the sensitivity of the LIBS technique. This study proved that an optimized value of the etching time of Si during etching by chemical processes and short delay times are required. Plasma parameters [the electron temperature ( T e) and the electron number density ( N e)] were calculated from measured SP- and DP-LIBS spectra. The most important result of this study is the much higher DP-LIBS intensity observed on Si (100) as compared to Si (111) for measurements under the same experimental conditions. This study could provide important reference data for the design and optimization of DP-LIBS systems involved in plasma-facing components diagnostics.

  16. Breast Feeding.

    ERIC Educational Resources Information Center

    International Children's Centre, Paris (France).

    This set of documents consists of English, French, and Spanish translations of four pamphlets on breast-feeding. The pamphlets provide information designed for lay persons, academics and professionals, health personnel and educators, and policy-makers. The contents cover health-related differences between breast and bottle milk; patterns of…

  17. Tube Feedings.

    ERIC Educational Resources Information Center

    Plummer, Nancy

    This module on tube feedings is intended for use in inservice or continuing education programs for persons who work in long-term care. Instructor information, including teaching suggestions and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then provided. A brief discussion follows…

  18. Long-wave, infrared laser-induced breakdown (LIBS) spectroscopy emissions from energetic materials.

    PubMed

    Yang, Clayton S-C; Brown, Ei E; Hommerich, Uwe; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

    2012-12-01

    Laser-induced breakdown spectroscopy (LIBS) has shown great promise for applications in chemical, biological, and explosives sensing and has significant potential for real-time standoff detection and analysis. In this study, LIBS emissions were obtained in the mid-infrared (MIR) and long-wave infrared (LWIR) spectral regions for potential applications in explosive material sensing. The IR spectroscopy region revealed vibrational and rotational signatures of functional groups in molecules and fragments thereof. The silicon-based detector for conventional ultraviolet-visible LIBS operations was replaced with a mercury-cadmium-telluride detector for MIR-LWIR spectral detection. The IR spectral signature region between 4 and 12 μm was mined for the appearance of MIR and LWIR-LIBS emissions directly indicative of oxygenated breakdown products as well as dissociated, and/or recombined sample molecular fragments. Distinct LWIR-LIBS emission signatures from dissociated-recombination sample molecular fragments between 4 and 12 μm are observed for the first time. PMID:23231901

  19. Improvements in discrimination of bulk and trace elements in long-wavelength double pulse LIBS

    NASA Astrophysics Data System (ADS)

    Freeman, J. R.; Diwakar, P. K.; Harilal, S. S.; Hassanein, A.

    2014-12-01

    In this work we study the effectiveness of long-wavelength heating in double pulse (DP) LIBS, quantitatively comparing figures of merit with those from traditional single pulse (SP) LIBS. The first laser pulse serves as the source of sample ablation, creating an aerosol-like plume that is subsequently reheated by the second laser pulse. At power densities used, the long-wavelength CO2 laser pulse does not ablate any of the solid sample in the atmospheric conditions investigated, meaning plasma emission and enhanced signal can be entirely attributed to the reheated plume rather than increased sample ablation. The signal discrimination was improved significantly using long-wavelength DP-LIBS. For bulk elemental analysis, DP-LIBS provided maximum enhancements of about 14 and 15 times for S/N and S/B, respectively, compared to SP-LIBS using the same quantity of ablated sample. For trace elemental analysis, maximum enhancements of about 7 and 4 times for S/N and S/B, respectively, were observed. These improvements are attributed to effective coupling between the second heating pulse and expanding plume and more efficient excitation of plume species than from the single pulse alone. Most significant improvements were observed in the case of low prepulse energy and minimal sample ablation. While bulk elemental analysis observed improvements for all prepulse energies studied, trace element discrimination only significantly improved for the lowest prepulse energy studied.

  20. The libRadtran software package for radiative transfer calculations (Version 2.0)

    NASA Astrophysics Data System (ADS)

    Emde, C.; Buras-Schnell, R.; Kylling, A.; Mayer, B.; Gasteiger, J.; Hamann, U.; Kylling, J.; Richter, B.; Pause, C.; Dowling, T.; Bugliaro, L.

    2015-12-01

    libRadtran is a widely used software package for radiative transfer calculations. It allows to compute (polarized) radiances, irradiances, and actinic fluxes in the solar and thermal spectral regions. libRadtran has been used for various applications, including remote sensing of clouds, aerosols and trace gases in the Earth's atmosphere, climate studies, e.g., for the calculation of radiative forcing due to different atmospheric components, for UV-forcasting, the calculation of photolysis frequencies, and for remote sensing of other planets in our solar system. The package has been described in Mayer and Kylling (2005).. Since then several new features have been included, for example polarization, Raman scattering, a new molecular gas absorption parameterization, and several new cloud and aerosol scattering parameterizations. Furthermore a graphical user interface is now available which greatly simplifies the usage of the model, especially for new users. This paper gives an overview of libRadtran version 2.0 with focus on new features. A complete description of libRadtran and all its input options is given in the user manual included in the libRadtran software package, which is freely available at http://www.libradtran.org.

  1. The libRadtran software package for radiative transfer calculations (version 2.0.1)

    NASA Astrophysics Data System (ADS)

    Emde, Claudia; Buras-Schnell, Robert; Kylling, Arve; Mayer, Bernhard; Gasteiger, Josef; Hamann, Ulrich; Kylling, Jonas; Richter, Bettina; Pause, Christian; Dowling, Timothy; Bugliaro, Luca

    2016-05-01

    libRadtran is a widely used software package for radiative transfer calculations. It allows one to compute (polarized) radiances, irradiance, and actinic fluxes in the solar and thermal spectral regions. libRadtran has been used for various applications, including remote sensing of clouds, aerosols and trace gases in the Earth's atmosphere, climate studies, e.g., for the calculation of radiative forcing due to different atmospheric components, for UV forecasting, the calculation of photolysis frequencies, and for remote sensing of other planets in our solar system. The package has been described in Mayer and Kylling (2005). Since then several new features have been included, for example polarization, Raman scattering, a new molecular gas absorption parameterization, and several new parameterizations of cloud and aerosol optical properties. Furthermore, a graphical user interface is now available, which greatly simplifies the usage of the model, especially for new users. This paper gives an overview of libRadtran version 2.0.1 with a focus on new features. Applications including these new features are provided as examples of use. A complete description of libRadtran and all its input options is given in the user manual included in the libRadtran software package, which is freely available at http://www.libradtran.org.

  2. Ultrasonic Nebulizer Assisted LIBS: a Promising Metal Elements Detection Method for Aqueous Sample Analysis

    NASA Astrophysics Data System (ADS)

    Zhong, Shilei; Zheng, Ronger; Lu, Yuan; Cheng, Kai; Xiu, Junshan

    2015-11-01

    A newly developed approach for trace metal elements detection for aqueous samples analysis is presented in this paper. The idea of this approach is to improve ablation efficiency by transforming the liquid sample into a dense cloud of droplets using an ultrasonic nebulizer. The resulting droplets are then subjected to analysis by laser induced breakdown spectroscopy (LIBS). A purpose-built ultrasonic nebulizer assisted LIBS (UN-LIBS) system has been applied to the analysis of aqueous samples at trace levels of concentration. Experimental investigations of solution samples were carried out with various dissolved trace metal elements (Mn, Zn, Cu, Pb, Fe, Mg and Na) using this approach. The characteristics of UN-LIBS signal of the elements were investigated regarding the lifetime and S/B ratio and the calibration curves for trace metal elements analyses. The obtained LODs are comparable or much better than the LODS of the reported signal enhancement approaches when the laser pulse energy was as low as 30 mJ. The good linearity of calibration curves and the low LODs shows the potential ability of this method for metal elements analysis application. The density of the electrons was calculated by measuring the Stark width of the line of Hα. The possible mechanism of the LIBS signal enhancement of this approach was briefly discussed. supported by National Natural Science Foundation of China (No. 11104153)

  3. Polarised black holes in AdS

    NASA Astrophysics Data System (ADS)

    Costa, Miguel S.; Greenspan, Lauren; Oliveira, Miguel; Penedones, João; Santos, Jorge E.

    2016-06-01

    We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global AdS 4 with conformal boundary {S}2× {{{R}}}t. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic AdS behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an AdS soliton that includes the full backreaction of the electric field on the AdS geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both AdS soliton and black hole phases. The corresponding phase diagram generalizes the Hawking-Page phase transition. The AdS soliton dominates the low temperature phase and the black hole the high temperature phase, with a critical temperature that decreases as the external electric field increases. Finally, we consider the simple case of a free charged scalar field on {S}2× {{{R}}}t with conformal coupling. For a field in the SU(N ) adjoint representation we compare the phase diagram with the above gravitational system.

  4. Application of laser induced breakdown spectroscopy (LIBS) to Mars polar exploration : LIBS analysis of water ice and water ice/soil mixtures

    SciTech Connect

    Arp, Z. A.; Cremers, D. A.; Wiens, R. C.

    2004-01-01

    The polar regions of Mars are of great interest due to the presence of water ice and CO{sub 2} ice combined with wind blown deposits. Due to seasonal changes and repeated cycles of precipitating dusts and H{sub 2}O, geological samples appear to have built up in the polar regions. These polar layered deposits (PLD) may include volcanic ash, fallout from surface impacts, evaporates from subliming lakes and seas and even wind blown ancient microbial life. The ability to examine the PLDs will be of great importance in the study of past Martian geological history and the determination of the past presence of life on Mars. Analysis of the ice fields which are present in the polar regions of Mars will almost certainly be of great interest to future surface rovers and landers to this region. The use of LIBS will maximize the scientific return of these missions. Through the development of a compact sensor head and a pan and tilt mechanism, analysis of PLD may be made in areas that are otherwise inaccessible to either a lander or a surface rover. This gives LIBS a significant advantage over other analysis techniques which require more than just optical access. Also, through the use of repetitive laser pulses it will be possible to ablate away the water ice layer to better examine the PLDs which exist below the surface. Another potential use for LIBS is the analysis of retrieved ice core samples. Laser pulses formed along the length of the ice core can monitor composition as a function of depth. This method has already been shown to work for mineral drill cores and terrestrial ice cores using laser ablation ICP-MS. Prior work on the use of LIBS for analysis of ice has focused on the detection of trace metal ions in the ice. To our knowledge no further work has been reported on the use of LIBS for analysis of water ice and water ice/soil mixtures. Here we will examine in detail the detection capabilities of LIBS on water ice and water ice/soil mixtures in an atmosphere similar

  5. Combined LIBS-Raman for remote detection and characterization of biological samples

    NASA Astrophysics Data System (ADS)

    Anderson, Aaron S.; Mukundan, Harshini; McInroy, Rhonda E.; Clegg, Samuel M.

    2015-03-01

    Laser-Induced Breakdown Spectroscopy (LIBS) and Raman Spectroscopy have rich histories in the analysis of a wide variety of samples in both in situ and remote configurations. Our team is working on building a deployable, integrated Raman and LIBS spectrometer (RLS) for the parallel elucidation of elemental and molecular signatures under Earth and Martian surface conditions. Herein, results from remote LIBS and Raman analysis of biological samples such as amino acids, small peptides, mono- and disaccharides, and nucleic acids acquired under terrestrial and Mars conditions are reported, giving rise to some interesting differences. A library of spectra and peaks of interest were compiled, and will be used to inform the analysis of more complex systems, such as large peptides, dried bacterial spores, and biofilms. These results will be presented and future applications will be discussed, including the assembly of a combined RLS spectroscopic system and stand-off detection in a variety of environments.

  6. Detection of biological contaminants on foods and food surfaces using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Multari, Rosalie A; Cremers, David A; Dupre, Jo Anne M; Gustafson, John E

    2013-09-11

    The rapid detection of biological contaminants, such as Escherichia coli O157:H7 and Salmonella enterica , on foods and food-processing surfaces is important to ensure food safety and streamline the food-monitoring process. Laser-induced breakdown spectroscopy (LIBS) is an ideal candidate technology for this application because sample preparation is minimal and results are available rapidly (seconds to minutes). Here, multivariate regression analysis of LIBS data is used to differentiate the live bacterial pathogens E. coli O157:H7 and S. enterica on various foods (eggshell, milk, bologna, ground beef, chicken, and lettuce) and surfaces (metal drain strainer and cutting board). The type (E. coli or S. enterica) of bacteria could be differentiated in all cases studied along with the metabolic state (viable or heat killed). This study provides data showing the potential of LIBS for the rapid identification of biological contaminants using spectra collected directly from foods and surfaces. PMID:23941554

  7. Combined LIBS-Raman for remote detection and characterization of biological samples

    SciTech Connect

    Anderson, Aaron S.; Mukundan, Harshini; Mcinroy, Rhonda E.; Clegg, Samuel M.

    2015-02-07

    Laser-Induced Breakdown Spectroscopy (LIBS) and Raman Spectroscopy have rich histories in the analysis of a wide variety of samples in both in situ and remote configurations. Our team is working on building a deployable, integrated Raman and LIBS spectrometer (RLS) for the parallel elucidation of elemental and molecular signatures under Earth and Martian surface conditions. Herein, results from remote LIBS and Raman analysis of biological samples such as amino acids, small peptides, mono- and disaccharides, and nucleic acids acquired under terrestrial and Mars conditions are reported, giving rise to some interesting differences. A library of spectra and peaks of interest were compiled, and will be used to inform the analysis of more complex systems, such as large peptides, dried bacterial spores, and biofilms. Lastly, these results will be presented and future applications will be discussed, including the assembly of a combined RLS spectroscopic system and stand-off detection in a variety of environments.

  8. Combined LIBS-Raman for remote detection and characterization of biological samples

    DOE PAGESBeta

    Anderson, Aaron S.; Mukundan, Harshini; Mcinroy, Rhonda E.; Clegg, Samuel M.

    2015-02-07

    Laser-Induced Breakdown Spectroscopy (LIBS) and Raman Spectroscopy have rich histories in the analysis of a wide variety of samples in both in situ and remote configurations. Our team is working on building a deployable, integrated Raman and LIBS spectrometer (RLS) for the parallel elucidation of elemental and molecular signatures under Earth and Martian surface conditions. Herein, results from remote LIBS and Raman analysis of biological samples such as amino acids, small peptides, mono- and disaccharides, and nucleic acids acquired under terrestrial and Mars conditions are reported, giving rise to some interesting differences. A library of spectra and peaks of interestmore » were compiled, and will be used to inform the analysis of more complex systems, such as large peptides, dried bacterial spores, and biofilms. Lastly, these results will be presented and future applications will be discussed, including the assembly of a combined RLS spectroscopic system and stand-off detection in a variety of environments.« less

  9. Automated interpretation of LIBS spectra using a fuzzy logic inference engine.

    PubMed

    Hatch, Jeremy J; McJunkin, Timothy R; Hanson, Cynthia; Scott, Jill R

    2012-03-01

    Automated interpretation of laser-induced breakdown spectroscopy (LIBS) data is necessary due to the plethora of spectra that can be acquired in a relatively short time. However, traditional chemometric and artificial neural network methods that have been employed are not always transparent to a skilled user. A fuzzy logic approach to data interpretation has now been adapted to LIBS spectral interpretation. Fuzzy logic inference rules were developed using methodology that includes data mining methods and operator expertise to differentiate between various copper-containing and stainless steel alloys as well as unknowns. Results using the fuzzy logic inference engine indicate a high degree of confidence in spectral assignment. PMID:22410914

  10. Temporally and spatially integrated elemental analysis algorithm for low-pressure micro-LIBS measurements

    SciTech Connect

    Mungas, Greg

    2007-07-01

    Microscopic laser-induced breakdown spectroscopy (micro-LIBS) is a promising measurement technique for determining the relative elemental abundances of microscopic spots. Currently, the predominant source of measurement accuracy errors for micro-LIBS is shown to be based on a constant plasma temperature assumption. To reduce these measurement errors particularly in low-pressure applications (i.e.,extraterrestrial environments), a mathematical data analysis algorithm is presented that utilizes the many linear independent emission lines per element to estimate the time-integrated state of the plasma in the form of a plasma state matrix coupled with a vector of relative elemental abundances in the observed emission.

  11. Application of Handheld Laser-Induced Breakdown Spectroscopy (LIBS) to Geochemical Analysis.

    PubMed

    Connors, Brendan; Somers, Andrew; Day, David

    2016-05-01

    While laser-induced breakdown spectroscopy (LIBS) has been in use for decades, only within the last two years has technology progressed to the point of enabling true handheld, self-contained instruments. Several instruments are now commercially available with a range of capabilities and features. In this paper, the SciAps Z-500 handheld LIBS instrument functionality and sub-systems are reviewed. Several assayed geochemical sample sets, including igneous rocks and soils, are investigated. Calibration data are presented for multiple elements of interest along with examples of elemental mapping in heterogeneous samples. Sample preparation and the data collection method from multiple locations and data analysis are discussed. PMID:27170779

  12. Automated Interpretation of LIBS Spectra using a Fuzzy Logic Inference Engine

    SciTech Connect

    Jeremy J. Hatch; Timothy R. McJunkin; Cynthia Hanson; Jill R. Scott

    2012-02-01

    Automated interpretation of laser-induced breakdown spectroscopy (LIBS) data is necessary due to the plethora of spectra that can be acquired in a relatively short time. However, traditional chemometric and artificial neural network methods that have been employed are not always transparent to a skilled user. A fuzzy logic approach to data interpretation has now been adapted to LIBS spectral interpretation. A fuzzy logic inference engine (FLIE) was used to differentiate between various copper containing and stainless steel alloys as well as unknowns. Results using FLIE indicate a high degree of confidence in spectral assignment.

  13. Search for contact systems among EB-type binaries. II - ES Lib and AR Boo

    NASA Astrophysics Data System (ADS)

    Milano, L.; Barone, F.; Mancuso, S.; Russo, G.

    1989-03-01

    In a search of contact systems among EB-type binaries, the existing photometric observations of ES Lib and AR Boo have been analyzed. It is found that ES Lib is a semi-detached system, with the primary filling the Roche lobe. AR Boo is instead found to be a contact system, with no lobe overfilling, and with a large temperature difference between the components, but this solution has to be considered as temptative, because of the poor quality of the data and the lack of any spectroscopic information.

  14. Scaling Users' Perceptions of Library Service Quality Using Item Response Theory: A LibQUAL+ [TM] Study

    ERIC Educational Resources Information Center

    Wei, Youhua; Thompson, Bruce; Cook, C. Colleen

    2005-01-01

    LibQUAL+[TM] data to date have not been subjected to the modern measurement theory called polytomous item response theory (IRT). The data interpreted here were collected from 42,090 participants who completed the "American English" version of the 22 core LibQUAL+[TM] items, and 12,552 participants from Australia and Europe who completed the…

  15. Temperature and Electron Density Determination on Laser-Induced Breakdown Spectroscopy (LIBS) Plasmas: A Physical Chemistry Experiment

    ERIC Educational Resources Information Center

    Najarian, Maya L.; Chinni, Rosemarie C.

    2013-01-01

    This laboratory is designed for physical chemistry students to gain experience using laser-induced breakdown spectroscopy (LIBS) in understanding plasma diagnostics. LIBS uses a high-powered laser that is focused on the sample causing a plasma to form. The emission of this plasma is then spectrally resolved and detected. Temperature and electron…

  16. Feed Formulation and Manufacture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter provides information on feed formulation and manufacture. To formulate and manufacture high quality fish feeds, including tilapia feeds, one should have knowledge of nutrient requirements, nutrient composition, digestibility, and availability of feed ingredients; impacts of manufacturin...

  17. LIBS-based detection of geological samples at low pressures (<0.001 torr) for moon and asteroid exploration.

    SciTech Connect

    Harris, R. D.; Cremers, D. A.; Khoo, C.; Benelli, K. M.

    2005-01-01

    LIBS is under development for future use on surface probes to Mars. Under simulated Mars atmospheric composition and pressure (7 torr, predominately CO{sub 2}), LIBS has been shown useful for qualitative and quantitative analysis of geological samples at close and stand-off distances (19 m). Because of its many advantages compared to previously deployed and current in-use methods of elemental analysis (e.g. x-ray fluorescence, APXS), LIBS has potential for application to other planetary bodies. Of particular interest are the Moon and asteroids having very low ambient gas pressures at the surface. Because the laser plasma used by LIBS is sensitive to the surrounding atmosphere, it is important to determine analysis capabilities under these conditions. The results of a study of LIBS capabilities at low pressure is presented here for both in-situ and stand-off analysis.

  18. Capabilities of LIBS for analysis of geological samples at stand-off distances in a Mars atmosphere

    SciTech Connect

    Cremers, D. A.; Wiens, R. C.; Ferris, M. J.; Brennetot, R.; Maurice, S.

    2002-01-01

    The use of LIBS for stand-off elemental analysis of geological and other samples in a simulated Mars atmosphere is being evaluated. Analytical capabilities, matrix effects, and other factors effecting analysis are being determined. Through funding from NASA's Mars Instrument Development Program (MIDP), we have been evaluating the use of LIBS for future use on landers and rovers to Mars. Of particular interest is the use of LIBS for stand-off measurements of geological samples up to 20 meters from the instrument. Very preliminary work on such remote LIBS measurements based on large laboratory type equipment was carried out about a decade ago. Recent work has characterized the capabilities using more compact instrumentation and some measurements have been conducted with LIBS on a NASA rover testbed.

  19. Getting More Value from the LibQUAL+® Survey: The Merits of Qualitative Analysis and Importance-Satisfaction Matrices in Assessing Library Patron Comments

    ERIC Educational Resources Information Center

    Detlor, Brian; Ball, Kathryn

    2015-01-01

    This paper examines the merit of conducting a qualitative analysis of LibQUAL+® survey comments as a means of leveraging quantitative LibQUAL+ results, and using importance-satisfaction matrices to present and assess qualitative findings. Comments collected from the authors' institution's LibQUAL+ survey were analyzed using a codebook based on…

  20. Smeared antibranes polarise in AdS

    NASA Astrophysics Data System (ADS)

    Gautason, Fridrik Freyr; Truijen, Brecht; Van Riet, Thomas

    2015-07-01

    In the recent literature it has been questioned whether the local backreaction of antibranes in flux throats can induce a perturbative brane-flux decay. Most evidence for this can be gathered for D6 branes and D p branes smeared over 6 - p compact directions, in line with the absence of finite temperature solutions for these cases. The solutions in the literature have flat worldvolume geometries and non-compact transversal spaces. In this paper we consider what happens when the worldvolume is AdS and the transversal space is compact. We show that in these circumstances brane polarisation smoothens out the flux singularity, which is an indication that brane-flux decay is prevented. This is consistent with the fact that the cosmological constant would be less negative after brane-flux decay. Our results extend recent results on AdS7 solutions from D6 branes to AdS p+1 solutions from D p branes. We show that supersymmetry of the AdS solutions depend on p non-trivially.

  1. AdS orbifolds and Penrose limits

    SciTech Connect

    Alishahiha, Mohsen; Sheikh-Jabbari, Mohammad M.; Tatar, Radu

    2002-12-09

    In this paper we study the Penrose limit of AdS{sub 5} orbifolds. The orbifold can be either in the pure spatial directions or space and time directions. For the AdS{sub 5}/{Lambda} x S{sup 5} spatial orbifold we observe that after the Penrose limit we obtain the same result as the Penrose limit of AdS{sub 5} x S{sup 5}/{Lambda}. We identify the corresponding BMN operators in terms of operators of the gauge theory on R x S{sup 3}/{Lambda}. The semi-classical description of rotating strings in these backgrounds have also been studied. For the spatial AdS orbifold we show that in the quadratic order the obtained action for the fluctuations is the same as that in S{sup 5} orbifold, however, the higher loop correction can distinguish between two cases.

  2. Detection of Anomalies in Citrus Leaves Using Laser-Induced Breakdown Spectroscopy (LIBS).

    PubMed

    Sankaran, Sindhuja; Ehsani, Reza; Morgan, Kelly T

    2015-08-01

    Nutrient assessment and management are important to maintain productivity in citrus orchards. In this study, laser-induced breakdown spectroscopy (LIBS) was applied for rapid and real-time detection of citrus anomalies. Laser-induced breakdown spectroscopy spectra were collected from citrus leaves with anomalies such as diseases (Huanglongbing, citrus canker) and nutrient deficiencies (iron, manganese, magnesium, zinc), and compared with those of healthy leaves. Baseline correction, wavelet multivariate denoising, and normalization techniques were applied to the LIBS spectra before analysis. After spectral pre-processing, features were extracted using principal component analysis and classified using two models, quadratic discriminant analysis and support vector machine (SVM). The SVM resulted in a high average classification accuracy of 97.5%, with high average canker classification accuracy (96.5%). LIBS peak analysis indicated that high intensities at 229.7, 247.9, 280.3, 393.5, 397.0, and 769.8 nm were observed of 11 peaks found in all the samples. Future studies using controlled experiments with variable nutrient applications are required for quantification of foliar nutrients by using LIBS-based sensing. PMID:26163130

  3. Multivariate classification of pigments and inks using combined Raman spectroscopy and LIBS.

    PubMed

    Hoehse, Marek; Paul, Andrea; Gornushkin, Igor; Panne, Ulrich

    2012-02-01

    The authenticity of objects and artifacts is often the focus of forensic analytic chemistry. In document fraud cases, the most important objective is to determine the origin of a particular ink. Here, we introduce a new approach which utilizes the combination of two analytical methods, namely Raman spectroscopy and laser-induced breakdown spectroscopy (LIBS). The methods provide complementary information on both molecular and elemental composition of samples. The potential of this hyphenation of spectroscopic methods is demonstrated for ten blue and black ink samples on white paper. LIBS and Raman spectra from different inks were fused into a single data matrix, and the number of different groups of inks was determined through multivariate analysis, i.e., principal component analysis, soft independent modelling of class analogy, partial least-squares discriminant analysis, and support vector machine. In all cases, the results obtained with the combined LIBS and Raman spectra were found to be superior to those obtained with the individual Raman or LIBS data sets. PMID:21845528

  4. Users' Hierarchical Perspectives on Library Service Quality: A "LibQUAL+" Study.

    ERIC Educational Resources Information Center

    Cook, Colleen; Heath, Fred; Thompson, Bruce

    2001-01-01

    The "LibQUAL+" diagnostic tool, product of the Association of Research Libraries (ARL), shows that although a single factor dominates user thinking about library service quality, all items in the survey suffuse this factor. Several first-order factors contribute unique information to the notion of service quality. As different users place varying…

  5. Users' Perceptions of Library Service Quality: A LibQUAL+ Qualitative Study.

    ERIC Educational Resources Information Center

    Cook, Colleen; Heath, Fred M.

    2001-01-01

    Describes a study of ARL (Association of Research Libraries) members called LibQUAL+ that identified users' perceptions of library service quality and measured gaps between expected service and perceived service. Discusses results of user interviews regarding information seeking behavior; self reliance; ubiquity and ease of access; and hours of…

  6. Development of an Automated LIBS Analytical Test System Integrated with Component Control and Spectrum Analysis Capabilities

    NASA Astrophysics Data System (ADS)

    Ding, Yu; Tian, Di; Chen, Feipeng; Chen, Pengfei; Qiao, Shujun; Yang, Guang; Li, Chunsheng

    2015-08-01

    The present paper proposes an automated Laser-Induced Breakdown Spectroscopy (LIBS) analytical test system, which consists of a LIBS measurement and control platform based on a modular design concept, and a LIBS qualitative spectrum analysis software and is developed in C#. The platform provides flexible interfacing and automated control; it is compatible with different manufacturer component models and is constructed in modularized form for easy expandability. During peak identification, a more robust peak identification method with improved stability in peak identification has been achieved by applying additional smoothing on the slope obtained by calculation before peak identification. For the purpose of element identification, an improved main lines analysis method, which detects all elements on the spectral peak to avoid omission of certain elements without strong spectral lines, is applied to element identification in the tested LIBS samples. This method also increases the identification speed. In this paper, actual applications have been carried out. According to tests, the analytical test system is compatible with components of various models made by different manufacturers. It can automatically control components to get experimental data and conduct filtering, peak identification and qualitative analysis, etc. on spectral data. supported by the National Major Scientific Instruments and Equipment Development Special Funds of China (No. 2011YQ030113)

  7. Evaluation of the efficacy of a portable LIBS system for detection of CWA on surfaces.

    PubMed

    L'Hermite, D; Vors, E; Vercouter, T; Moutiers, G

    2016-05-01

    Laser-induced breakdown spectroscopy (LIBS) is a laser-based optical technique particularly suited for in situ surface analysis. A portable LIBS instrument was tested to detect surface chemical contamination by chemical warfare agents (CWAs). Test of detection of surface contamination was carried out in a toxlab facility with four CWAs, sarin (GB), lewisite (L1), mustard gas (HD), and VX, which were deposited on different substrates, wood, concrete, military green paint, gloves, and ceramic. The CWAs were detected by means of the detection of atomic markers (As, P, F, Cl, and S). The LIBS instrument can give a direct response in terms of detection thanks to an integrated interface for non-expert users or so called end-users. We have evaluated the capability of automatic detection of the selected CWAs. The sensitivity of our portable LIBS instrument was confirmed for the detection of a CWA at surface concentrations above 15 μg/cm(2). The simultaneous detection of two markers may lead to a decrease of the number of false positive. PMID:26906000

  8. CN and C2 vibrational spectra analysis in molecular LIBS of organic materials

    NASA Astrophysics Data System (ADS)

    Mousavi, S. J.; Hemati Farsani, M.; Darbani, S. M. R.; Mousaviazar, A.; Soltanolkotabi, M.; Eslami Majd, A.

    2016-05-01

    With the objective of investigation of the influence of molecular structure on CN violet and C2 Swan bands system spectra, plasma emissions from different organic materials, including polycyclic aromatic hydrocarbons, aromatic carboxylic acid, aliphatic carboxylic acid, amides and polymers, have been analyzed by laser-induced breakdown spectroscopy (LIBS) technique in air. To evaluate the influence of N2 and O2 molecules concentration on the CN and C2 molecular emissions, LIB spectra of four different samples have been recorded in air (approximately 80 % N2 and 20 % O2), nitrogen, oxygen and argon atmospheres. Experimental results indicate that the main reason for the absence of C2 emission in LIB spectra of samples which do not contain C-C bonds, when measurements were taken in air, is the presence of oxygen which could potentially deplete C2 emission rather than the absence of C-C bonds in their structure. Also, comparisons between experiment and theory spectra are made using a Nelder-Mead temperature program for CN and C2 bands with the ∆ν = 0 sequences from LIB spectra of different samples in various atmospheres. Furthermore, CN and C2 vibrational temperatures in Kelvin (K) are calculated from these spectral fittings. Both CN and C2 vibrational temperatures have highest values in argon atmosphere, and increasing the oxygen concentration in ambient atmosphere decreased those in most cases.

  9. StrBioLib: a Java library for development of custom computationalstructural biology applications

    SciTech Connect

    Chandonia, John-Marc

    2007-05-14

    Summary: StrBioLib is a library of Java classes useful fordeveloping software for computational structural biology research.StrBioLib contains classes to represent and manipulate proteinstructures, biopolymer sequences, sets of biopolymer sequences, andalignments between biopolymers based on either sequence or structure.Interfaces are provided to interact with commonly used bioinformaticsapplications, including (PSI)-BLAST, MODELLER, MUSCLE, and Primer3, andtools are provided to read and write many file formats used to representbioinformatic data. The library includes a general-purpose neural networkobject with multiple training algorithms, the Hooke and Jeeves nonlinearoptimization algorithm, and tools for efficient C-style string parsingand formatting. StrBioLib is the basis for the Pred2ary secondarystructure prediction program, is used to build the ASTRAL compendium forsequence and structure analysis, and has been extensively tested throughuse in many smaller projects. Examples and documentation are available atthe site below.Availability: StrBioLib may be obtained under the terms ofthe GNU LGPL license from http://strbio.sourceforge.net/Contact:JMChandonia@lbl.gov

  10. Advanced recognition of explosives in traces on polymer surfaces using LIBS and supervised learning classifiers.

    PubMed

    Serrano, Jorge; Moros, Javier; Sánchez, Carlos; Macías, Jorge; Laserna, J Javier

    2014-01-01

    The large similarity existing in the spectral emissions collected from organic compounds by laser-induced breakdown spectroscopy (LIBS) is a limiting factor for the use of this technology in the real world. Specifically, among the most ambitious challenges of today's LIBS involves the recognition of an organic residue when neglected on the surface of an object of identical nature. Under these circumstances, the development of an efficient algorithm to disclose the minute differences within this highly complex spectral information is crucial for a realistic application of LIBS in countering explosive threats. An approach cemented on scatter plots of characteristic emission features has been developed to identify organic explosives when located on polymeric surfaces (teflon, nylon and polyethylene). By using selected spectral variables, the approach allows to design a concise classifier for alerting when one of four explosives (DNT, TNT, RDX and PETN) is present on the surface of the polymer. Ordinary products (butter, fuel oil, hand cream, olive oil and motor oil) cause no confusion in the decisions taken by the classifier. With rates of false negatives and false positives below 5%, results demonstrate that the classification algorithm enables to label residues according to their harmful nature in the most demanding scenario for a LIBS sensor. PMID:24331046

  11. Usability Testing, User-Centered Design, and LibGuides Subject Guides: A Case Study

    ERIC Educational Resources Information Center

    Sonsteby, Alec; DeJonghe, Jennifer

    2013-01-01

    Usability testing has become a routine way for many libraries to ensure that their Web presence is user-friendly and accessible. At the same time, popular subject guide creation systems, such as LibGuides, decentralize Web content creation and put authorship into the hands of librarians who may not be trained in user-centered design principles. At…

  12. Special Collections and the New Web: Using LibGuides to Provide Meaningful Access

    ERIC Educational Resources Information Center

    Lewis, Barbara; Griffin, Melanie

    2011-01-01

    Librarians have long struggled to find user-friendly mediums to provide meaningful information to patrons using bibliographies, pathfinders, and subject guides with varying degrees of success. Content management systems, such as Springshare's LibGuides, have recently been developed to facilitate the creation of online subject guides. Special…

  13. Identification of frozen salt solutions combining LIBS and multivariate analysis methods

    NASA Astrophysics Data System (ADS)

    Schröder, S.; Pavlov, S.; Jessberger, E.; Hübers, H.

    2012-12-01

    Laser-induced breakdown spectroscopy (LIBS) is an emission spectroscopy technique and relies on evaporating material from the target by focusing radiation from a pulsed laser onto the sample surface. The generated plasma is analyzed spectroscopically and information about the elemental composition is obtained from specific atomic or ionic transitions and the associated emanating photons, which result in characteristic spectral lines. For the geochemical investigation of extraterrestrial surfaces LIBS has been suggested as a powerful analytical tool and is part of the payload on NASA's rover MSL (Mars Science Laboratory), which landed in the Gale crater on Mars in August 2012. This is the first time that LIBS is used for planetary science. In this study, salts, which are considered relevant for Martian geochemistry were investigated, including sulfates, chlorides, and perchlorates. An infrared Nd:YAG laser (1064 nm wavelength, up to 220 mJ, 8 ns pulse duration, 10 Hz repetition rate) generated the plasma at distances < 1 m. The plasma emission was detected with an echelle spectrometer with a time-gated intensified CCD enabling a continuous coverage from 280 nm to 900 nm. The salts were investigated in their pure form and in frozen salt solutions under simulated Martian atmospheric conditions with an appropriate gas mixture composed of 95.55 % Vol. CO2 at a pressure of 7 mbar. The influence of different gating parameters for time-resolved detection of the plasma was studied and parameters best suited for the LIBS analysis of ices were determined. The emission lines of metals are detectable with LIBS with high signal-to-noise ratios, which facilitates a relatively straightforward identification of the type of the cation. Due to weak excitation of the high-energy levels required for efficient radiative transitions of both sulfur and chlorine ions, their emission lines are typically weak and hardly detectable, in particular in the LIBS spectra of the ices. This

  14. [Effect of Characteristic Variable Extraction on Accuracy of Cu in Navel Orange Peel by LIBS].

    PubMed

    Li, Wen-bing; Yao, Ming-yin; Huang, Lin; Chen, Tian-bing; Zheng, Jian-hong; Fan, Shi-quan; Liu Mu-hua HE, Mu-hua; Lin, Jin-long; Ouyang, Jing-yi

    2015-07-01

    Heavy metals pollution in foodstuffs is more and more serious. It is impossible to satisfy the modern agricultural development by conventional chemical analysis. Laser induced breakdown spectroscopy (LIBS) is an emerging technology with the characteristic of rapid and nondestructive detection. But LIBS' s repeatability, sensitivity and accuracy has much room to improve. In this work, heavy metal Cu in Gannan Navel Orange which is the Jiangxi specialty fruit will be predicted by LIBS. Firstly, the navel orange samples were contaminated in our lab. The spectra of samples were collected by irradiating the peel by optimized LIBS parameters. The laser energy was set as 20 mJ, delay time of Spectral Data Gathering was set as 1.2 micros, the integration time of Spectral data gathering was set as 2 ms. The real concentration in samples was obtained by AAS (atom absorption spectroscopy). The characteristic variables Cu I 324.7 and Cu I 327.4 were extracted. And the calibration model was constructed between LIBS spectra and real concentration about Cu. The results show that relative error of the predicted concentrations of three relational model were 7.01% or less, reached a minimum of 0.02%, 0.01% and 0.02% respectively. The average relative errors were 2.33%, 3.10% and 26.3%. Tests showed that different characteristic variables decided different accuracy. It is very important to choose suitable characteristic variable. At the same time, this work is helpful to explore the distribution of heavy metals between pulp and peel. PMID:26717771

  15. [Determination of Cu in Shell of Preserved Egg by LIBS Coupled with PLS].

    PubMed

    Hu, Hui-qin; Xu, Xue-hong; Liu, Mu-hua; Tu, Jian-ping; Huang, Le; Huang, Lin; Yao, Ming-yin; Chen, Tian-bing; Yang, Ping

    2015-12-01

    In this work, the content of copper in the shell of preserved eggs were determined directly by Laser induced breakdown spectroscopy (LIBS), and the characteristics lines of Cu was obtained. The samples of eggshell were pretreated by acid wet digestion, and the real content of Cu was obtained by atomic absorption spectrophotometer (AAS). Due to the test precision and accuracy of LIBS was influenced by a serious of factors, for example, the complex matrix effect of sample, the enviro nment noise, the system noise of the instrument, the stability of laser energy and so on. And the conventional unvariate linear calibration curve between LIBS intensity and content of element of sample, such as by use of Schiebe G-Lomakin equation, can not meet the requirement of quantitative analysis. In account of that, a kind of multivariate calibration method is needed. In this work, the data of LIBS spectra were processed by partial least squares (PLS), the precision and accuracy of PLS model were compared by different smoothing treatment and five pretreatment methods. The result showed that the correlation coefficient and the accuracy of the PLS model were improved, and the root mean square error and the average relative error were reduced effectively by 11 point smoothing with Multiplicative scatter correction (MSC) pretreatment. The results of the study show that, heavy metal Cu in preserved egg shells can be direct detected accurately by laser induced breakdown spectroscopy, and the next step batch tests will been conducted to find out the relationship of heavy metal Cu content in the preserved egg between the eggshell, egg white and egg yolk. And the goal of the contents of heavy metals in the egg white, egg yolk can be knew through determinate the eggshell by the LIBS can be achieved, to provide new method for rapid non-destructive testing technology for quality and satety of agricultural products. PMID:26964238

  16. Infant feeding practices in Malaysia.

    PubMed

    Chen, S T

    1978-12-01

    Retrospective nutritional data on 100 children, aged 6 months to 2 1/2 years, who were admitted to the University Hospital in Kuala Lumpur, Malaysia, was obtained by interviewing the mothers of the children. Analysis of the data revealed that 1) only 49% of the children were breast-fed as infants; 2) 50% of the mothers who did breast-feed discontinued breast-feeding before the children were 3 months old; and 3) the weaning diet of at least 1/3 of the children was inadequate. 18% of the children were Malays, 49% were Chinese, and 33% were Indian. The proportion of breast-fed children was highest among the Malays and lowest among the Chinese. Mothers with higher incomes tended to stop breast-feeding earlier than mothers with lower incomes. 67% of the women said they stopped breast-feeding due to inadequate lactation. Most of the children received supplementary foods at relatively early ages. 50% of the infants received starchy foods by the time they were 3 1/2 months old, and 50% received fruit or fruit juice by the time they were 3 1/2 months old. Vegetable products, meat, fish, and eggs were not added to the diet until the children were considerably older. Recommendations, based on the study findings, were 1) hospitals should discontinue the practice of deferring breast-feeding initiation for 24 hours after delivery; 2) mothers should be encouraged to breast-feed fully; and 3) health personnel should discourage the widespread use of costly precooked cereals for supplementary feeding. Tables depicted 1) the frequency distribution of the 100 children by income and by milk feeding patterns according to ethnic affiliation and 2) the cost of serving precooked cereals as compared to the cost of serving home cooked meals. PMID:755160

  17. A brief history of laser-induced breakdown spectroscopy: From the concept of atoms to LIBS 2012

    NASA Astrophysics Data System (ADS)

    Radziemski, Leon; Cremers, David

    2013-09-01

    LIBS did not appear de novo in 1962, but was built upon accomplishments of the past. These started with very old concepts of indivisible units (atomos), chemical and physical experiments and theoretical advances that took place in the late 19th and early 20th centuries, the development of the laser, the discovery of gas breakdown, and the realization of the application to spectrochemistry. We sketch the historical developments and focus as well on the advances in LIBS methodology and instrumentation over the past 50 years, culminating with a synopsis of the LIBS 2012 Conference in Luxor, Egypt.

  18. Preliminary study of laser-induced breakdown spectroscopy (LIBS) for a Venus mission

    SciTech Connect

    Arp, Z. A.; Cremers, D. A.; Wiens, R. C.

    2004-01-01

    Laser-Induced Breakdown Spectroscopy (LIBS) has been proposed as a candidate analysis system for missions to Mars, asteroids, and recently Venus. This technique has several distinct advantages over other techniques which have been used on past missions (X-Ray fluorescence on Viking 1 and 2, 1976; APXS on Pathfiider, 1997; MER, 2004). Two of the more important advantages LIBS has over other techniques for a mission to Venus is rapid elemental analysis of both high and low Z value elements and stand-off analysis at distances of many meters. Rapid elemental analysis and stand-off analysis are very important to missions to Venus due to the harsh environment at the planet surface. From the Venera missions it is known that on the Venusian surface the pressures are approximately 9.1 MPa (90 atm) and the temperature is near 735 K. For these reasons, the Soviet Venera surface probes had operational lifetimes of less than 2 hours. Currently Venus is the target of one of four missions specifically mentioned for consideration for NASA's New Frontier Program with a launch date of 2010 or earlier. In light of this, it is beneficial to evaluate different analysis methods such as LIBS, which offer to greatly increase the scientific return from such a mission. Currently we have begun to evaluate LIBS detection in an environment with pressures and compositions which are similar to those found on Venus. Although the temperature of Venus ({approx} 735 K) has not been taken into account in these experiments, due to the high temperature of the plasma ({approx}8000 K) signifcant perturbations of excitation characteristics sufficient to affect LIBS analytical capability would not be expected. Previous work, however, has shown that the pressure of the surrounding atmosphere can have a strong effect on the detection of elements in soil. These studies have mainly concentrated on pressures at or below earth ambient pressure, but one study has shown successful results at elevated pressures (3

  19. Nasogastric feeding tube

    MedlinePlus

    Feeding - nasogastric tube; NG tube; Bolus feeding; Continuous pump feeding; Gavage tube ... A nasogastric tube (NG tube) is a special tube that carries food and medicine to the stomach through the nose. It can be ...

  20. The AdS particle [rapid communication

    NASA Astrophysics Data System (ADS)

    Ghosh, Subir

    2005-09-01

    In this Letter we have considered a relativistic Nambu-Goto model for a particle in AdS metric. With appropriate gauge choice to fix the reparameterization invariance, we recover the previously discussed [S. Ghosh, P. Pal, Phys. Lett. B 618 (2005) 243, arxiv:hep-th/0502192] "exotic oscillator". The Snyder algebra and subsequently the κ-Minkowski spacetime are also derived. Lastly we comment on the impossibility of constructing a non-commutative spacetime in the context of open string where only a curved target space is introduced.

  1. A First Look at the Nonadiabatic Properties of Pulsating Accreting White Dwarfs of the GW Lib Type

    NASA Astrophysics Data System (ADS)

    Van Grootel, V.; Fontaine, G.; Brassard, P.; Dupret, M.-A.

    2015-06-01

    We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the-art white dwarf evolutionary sequences with varying envelope compositions, from pure hydrogen to pure helium. Using the same tools as in Van Grootel et al. (2013), where we have presented the first consistent view of the ZZ Ceti instability strip, we have mapped the GW Lib instability strip over the effective temperature-surface gravity plane, and as a function of envelope composition. We find that the location of the GW Lib instability domain is a strong and continuous function of the assumed envelope composition. We can accomodate all of the known GW Lib pulsators in various strips according to their atmospheric compositions.

  2. Meal-feeding rodents and toxicology research.

    PubMed

    Carey, Gale B; Merrill, Lisa C

    2012-08-20

    Most laboratory rodents used for toxicology studies are fed ad libitum, with unlimited access to food. As a result, ad libitum-fed rodents tend to overeat. Research demonstrates that ad libitum-fed rodents are physiologically and metabolically different from rodents fed controlled amounts of food at scheduled times (meal-fed). Ad libitum-fed rodents can develop hypertriglyceridemia, hypercholesterolemia, diet-induced obesity, nephropathy, cardiomyopathy, and pituitary, pancreatic, adrenal, and thyroid tumors, conditions likely to affect the results of toxicology research studies. In contrast, meal-feeding synchronizes biological rhythms and leads to a longer life span, lower body weight, lower body temperature, hypertrophy of the small intestine, and synchronization of hepatic and digestive enzymes. The circadian rhythms present in nearly all living organisms are entrained by light intensity and food intake, and peripheral clocks in all organs of the body, especially the GI tract and liver, are particularly sensitive to food intake. Feeding schedule has been demonstrated to alter the toxicity and metabolism of drugs including sodium valproate, chloral hydrate, acetaminophen, gentamicin, and methotrexate. Feeding schedule alters the expression of genes that code for Phase I, II, and III proteins, thereby altering the rate and amplitude of drug disposition. Rhythms of plasma insulin and glucagon that fluctuate with food ingestion are also altered by feeding schedule; ad libitum feeding promotes hyperinsulinemia which is a precursor for developing diabetes. The emerging field of chronopharmacology, the interaction of biological rhythms and drugs, will lead to optimizing the design and delivery of drugs in a manner that matches biological rhythms, but it is wise for toxicology researchers to consider feeding schedule when designing these experiments. It has been 10 years since the Society for Toxicologic Pathology voiced its position that feeding schedule is an

  3. Application of laser induced breakdown spectroscopy (LIBS) instrumentation for international safeguards

    SciTech Connect

    Barefield Ii, James E; Clegg, Samuel M; Lopez, Leon N; Le, Loan A; Veirs, D Kirk; Browne, Mike

    2010-01-01

    Advanced methodologies and improvements to current measurements techniques are needed to strengthen the effectiveness and efficiency of international safeguards. This need was recognized and discussed at a Technical Meeting on 'The Application of Laser Spectrometry Techniques in IAEA Safeguards' held at IAEA headquarters (September 2006). One of the principal recommendations from that meeting was the need to pursue the development of novel complementary access instrumentation based on Laser Induced Breakdown Spectroscopy (UBS) for the detection of gaseous and solid signatures and indicators of nuclear fuel cycle processes and associated materials'. Pursuant to this recommendation the Department of Safeguards (SG) under the Division of Technical Support (SGTS) convened the 'Experts and Users Advisory Meeting on Laser Induced Breakdown Spectroscopy (LIBS) for Safeguards Applications' also held at IAEA headquarters (July 2008). This meeting was attended by 12 LlBS experts from the Czech Republic, the European Commission, France, the Republic of South Korea, the United States of America, Germany, the United Kingdom of Great Britain, Canada, and Northern Ireland. Following a presentation of the needs of the IAEA inspectors, the LIBS experts agreed that needs as presented could be partially or fully fulfilled using LIBS instrumentation. Inspectors needs were grouped into the following broad categories: (1) Improvements to in-field measurements/environmental sampling; (2) Monitoring status of activities in Hot Cells; (3) Verify status of activity at a declared facility via process monitoring; and (4) Need for pre-screening of environmental samples before analysis. The primary tool employed by the IAEA to detect undeclared processes and activities at special nuclear material facilities and sites is environmental sampling. One of the objectives of the Next Generation Safeguards Initiative (NGSI) Program Plan calls for the development of advanced tools and methodologies to

  4. Analysis of water ice and ice/dust mixtures using laser-induced breakdown spectroscopy (LIBS).

    SciTech Connect

    Cremers, D. A.; Brown, Kari; Gibson, L. E.; Ferris, M. J.; Wiens, R. C.; Maurice, S.

    2003-01-01

    In 1992, LIBS was proposed as a new method for stand-off detection of geological samples for use on landers and rovers to Mars. Recently, there has been increased interest in the technique for this and other space applications and studies have determined some of the characteristics and capabilities of the method under the conditions that these measurements will have to be made. In addition to rocks and soils, there is interest in using LIBS to analyze ices and dusts entrained in ice . This is especially true for missions to the Mars polar regions . Of particular interest is determining the nature of polar layered deposits, the geochemistry of polar surface materials, detection of water ice and the distribution of ice, and the presence of possible organics in these materials (via C/N ratios)

  5. Pigment Identification on a XIV/XV c. Wooden Crucifix Using Raman and LIBS Techniques

    NASA Astrophysics Data System (ADS)

    Sawczak, M.; Sliwinski, G.; Kaminska, A.; Oujja, M.; Castillejo, M.; Domingo, C.; Klossowska, M.

    The Raman and laser-induced breakdown spectroscopy (LIBS) techniques were applied for the pigment identification in polychrome layers on a fourteenth/fifteenth century wooden crucifix. In the Raman spectra, characteristic bands associated with compounds of the pigment samples taken from different areas of the object are observed. Groups of bands corresponding to the original white, red, and green pigments allow the identification of chalk, vermilion, red lead, malachite, and azurite. From the presence of bands ascribed to Prussian blue (282, 538 cm?1) and chrome yellow (338, 360, 403 cm?1) known since eighteenth century, retouching of some statue parts can be concluded. The elemental composition is obtained from LIBS profiles recorded under excitation at 248 and 266 nm. The gold-leaf technique is identified and the presence of Cu, Pb, Cr, Fe, CN, C2, and Ca agrees with the pigment composition applied for re-touching and observed in the Raman bands.

  6. Probing crunching AdS cosmologies

    NASA Astrophysics Data System (ADS)

    Kumar, S. Prem; Vaganov, Vladislav

    2016-02-01

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of {N}=8 supergravity on AdS4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor ã max. Radial geodesics connecting antipodal points necessarily have de Sitter energy Ɛ ≲ ã max, while geodesics with Ɛ > ã max terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outward" in the Penrose diagram for the deformed AdS backgrounds, and thus geodesic limits of the antipodal correlators do not directly probe the crunch. Beyond the geodesic limit, we point out that the scalar wave equation, analytically continued into the FRW patch, has a potential which is singular at the crunch along with complex WKB turning points in the vicinity of the FRW crunch. We then argue that the frequency space Green's function has a branch point determined by ã max which corresponds to the lowest quasinormal frequency.

  7. CosmoBolognaLib: Open source C++ libraries for cosmological calculations

    NASA Astrophysics Data System (ADS)

    Marulli, Federico; Veropalumbo, Alfonso; Moresco, Michele

    2015-11-01

    CosmoBolognaLib contains numerical libraries for cosmological calculations; written in C++, it is intended to define a common numerical environment for cosmological investigations of the large-scale structure of the Universe. The software aids in handling real and simulated astronomical catalogs by measuring one-point, two-point and three-point statistics in configuration space and performing cosmological analyses. These open source libraries can be included in either C++ or Python codes.

  8. A full featured handheld LIBS analyzer with early results for defense and security

    NASA Astrophysics Data System (ADS)

    Day, D.; Connors, B.; Jennings, M.; Egan, J.; Derman, K.; Soucy, P.; Moller, S.; Sackett, D.

    2015-06-01

    A handheld LIBS instrument has been designed that includes most features found in large bench-top systems including variable gating, argon purge, high resolution, wide spectral range, sample rastering, and video targeting. In this presentation we will discuss the feature selection, trade-off decisions and new developments that made this kind of size reduction possible. Early results will be presented for elemental presence detection and quantification with specific emphasis on defense and security.

  9. Lithium-Boron (Li-B) Monolayers: First-Principles Cluster Expansion and Possible Two-Dimensional Superconductivity.

    PubMed

    Wu, Chao; Wang, Hua; Zhang, Jiajia; Gou, Gaoyang; Pan, Bicai; Li, Ju

    2016-02-01

    Recent works demonstrated that the superconductivity at two-dimensional (2-D) can be achieved in Li-decorated graphene (Nature Phys. 2012, 8, 131 and Proc. Natl. Acad. Sci. 2015, 112, 11795). Inspired by the progress made in graphene, we predict by using the first-principles calculations that Li-incorporated B monolayers (Li-B monolayers) can be alternative 2-D superconductors. First-principles cluster expansion approach was used to evaluate the structural diversity and energetic stability of the 2-D Li-B monolayers by treating them as ternary Lix⬡yB1-x-y pseudoalloys (⬡ refers to B hexagonal hole). After thoroughly exploring the Li-B configuration space, several well-ordered and stable Li-B monolayers were identified. Detailed analyses regarding the electronic structures and lattice dynamics properties of the predicted Li-B monolayers were performed. Compared with the non-superconducting pure B-sheet, some predicted Li-B monolayers can exhibit the phonon-mediated superconducting properties above the liquid helium temperature. PMID:26732306

  10. Final report on feasibility of real-time geochemical analysis at Yucca Mountain, Nevada, using LIBS technology

    SciTech Connect

    Blacic, J.D.; Pettit, D.R.; Cremers, D.A.

    1996-12-01

    Laser-induced breakdown spectroscopy (LIBS) is an analytic method whereby an intense laser pulse is used to vaporize and excite a small volume of material into atomic emission. Calibrated spectral analysis of the laser spark light provides detection and quantification of the elemental composition of the target material. We performed laboratory and field tests to assess the feasibility of developing field-portable LIBS-based instruments for real-time analyses of Yucca Mountain rocks in conjunction with Yucca Mountain Project drilling, coring, sampling, and characterization tasks. We developed one prototype instrument designed to analyze air core drilling dust and another prototype instrument designed to analyze rock and fracture surfaces. In realistic field tests at the Exploratory Studies Facility at Yucca Mountain, Nevada, we demonstrated that the LIBS prototypes are capable of measuring major, minor, and some trace elements in real time. Laboratory LIBS analyses show that we can identify characteristic element ratios in a range of manganese oxide minerals present at Yucca Mountain as fracture surface coatings and matrix grains. Preliminary LIBS analyses also indicate that the U/Na ratio may distinguish tuffs containing the hazardous zeolite mineral erionite from non-erionite bearing tuffs, and that a LIBS-based instrument may be useful to detect in real time the probable presence of erionite encountered in core drilling and other operations at Yucca Mountain.

  11. Rapid Analysis of Ash Composition Using Laser-Induced Breakdown Spectroscopy (LIBS)

    SciTech Connect

    Tyler L. Westover

    2013-01-01

    Inorganic compounds are known to be problematic in the thermochemical conversion of biomass to syngas and ultimately hydrocarbon fuels. The elements Si, K, Ca, Na, S, P, Cl, Mg, Fe, and Al are particularly problematic and are known to influence reaction pathways, contribute to fouling and corrosion, poison catalysts, and impact waste streams. Substantial quantities of inorganic species can be entrained in the bark of trees during harvest operations. Herbaceous feedstocks often have even greater quantities of inorganic constituents, which can account for as much as one-fifth of the total dry matter. Current methodologies to measure the concentrations of these elements, such as inductively coupled plasma-optical emission spectrometry/mass spectrometry (ICP-OES/MS) are expensive in time and reagents. This study demonstrates that a new methodology employing laser-induced breakdown spectroscopy (LIBS) can rapidly and accurately analyze the inorganic constituents in a wide range of biomass materials, including both woody and herbaceous examples. This technique requires little or no sample preparation, does not consume any reagents, and the analytical data is available immediately. In addition to comparing LIBS data with the results from ICP-OES methods, this work also includes discussions of sample preparation techniques, calibration curves for interpreting LIBS spectra, minimum detection limits, and the use of internal standards and standard reference materials.

  12. Analysis and spectral assignments of mixed actinide oxide samples using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Barefield, James E; Judge, Elizabeth J; Berg, John M; Willson, Stephen P; Le, Loan A; Lopez, Leon N

    2013-04-01

    In this paper, we report for the first time the identification and assignments of complex atomic emission spectra of mixed actinide oxides using laser-induced plasma spectroscopy or laser-induced breakdown spectroscopy (LIBS). Preliminary results of LIBS measurements on samples of uranium dioxide (UO2)/plutonium dioxide (PuO2) and UO2/PuO2/americium dioxide (AmO2)/neptunium dioxide (NpO2) simulated fuel pellets (or mixed actinide oxide samples) are reported and discussed. We have identified and assigned >800 atomic emission lines for a UO2/PuO2/AmO2/NpO2 fuel pellet thus far. The identification and assignments of spectral emission lines for U, Pu, and Am are consistent with wavelength data from the literature. However, only a few emission lines have been assigned with a high degree of confidence for Np compared with atomic emission data from the literature. We also indicate where atomic emission lines for Cm would most likely appear in the spectral regions shown. Finally, we demonstrate that a LIBS system with a resolving power of approximately 20,000 is adequate for analyzing complex mixtures of actinide elements within the same sample. PMID:23601543

  13. Non-intrusive, on-line, simultaneous multi-species impurity monitoring in hydrogen using LIBS

    NASA Astrophysics Data System (ADS)

    Eseller, K. E.; Yueh, F.-Y.; Singh, J. P.

    2011-03-01

    Laser-induced breakdown spectroscopy (LIBS) has been evaluated for on-line, simultaneous multi-species impurity monitoring in hydrogen. A miniature spectrometer with spectral coverage of 620-800 nm and a gated detection system with spectral coverage of 40 nm were both used to record LIBS spectra from the spark produced in sample gas by a frequency-doubled Nd YAG laser. The effect of pressure on detecting the impurity (e.g., nitrogen, argon, and oxygen) in hydrogen was studied. LIBS spectra with different impurity levels of nitrogen, argon, and oxygen were recorded, and the intensity of the spectral lines of Ar, O, N, and H observed were used to form calibration plots for impurity measurement. The limits of detection (LODs) for oxygen, argon, and nitrogen in hydrogen were estimated from the calibration obtained with both the gated and ungated detection. The hydrogen impurity measurements based on the ungated miniature system show reliable and reproductive results. But the LODs with this system are about four times higher than the LODs obtained with a gated detection system in this work.

  14. Measurement system for high-sensitivity LIBS analysis using ICCD camera in LabVIEW environment

    NASA Astrophysics Data System (ADS)

    Zaytsev, S. M.; Popov, A. M.; Zorov, N. B.; Labutin, T. A.

    2014-06-01

    A measurement system based on ultrafast (up to 10 ns time resolution) intensified CCD detector ``Nanogate-2V'' (Nanoscan, Russia) was developed for high-sensitivity analysis by Laser-Induced Breakdown Spectrometry (LIBS). LabVIEW environment provided a high level of compatibility with variety of electronic instruments and an easy development of user interface, while Visual Studio environment was used for creation of LabVIEW compatible dll library with the use of ``Nanogate-2V'' SDK. The program for camera management and laser-induced plasma spectra registration was created with the use of Call Library Node in LabVIEW. An algorithm of integration of the second device ADC ``PCI-9812'' (ADLINK) to the measurement system was proposed and successfully implemented. This allowed simultaneous registration of emission and acoustic signals under laser ablation. The measured resolving power of spectrometer-ICCD system was equal to 12000 at 632 nm. An electron density of laser plasma was estimated with the use of H-α Balmer line. Steel spectra obtained at different delays were used for selection of the optimal conditions for manganese analytical signal registration. The feature of accumulation of spectra from several laser pulses was shown. The accumulation allowed reliable observation of silver signal at 328.07 nm in the LIBS spectra of soil (CAg = 4.5 ppm). Finally, the correlation between acoustic and emission signals of plasma was found. Thus, technical possibilities of the developed LIBS system were demonstrated both for plasma diagnostics and analytical measurements.

  15. Composition analysis of medieval ceramics by laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Genc Oztoprak, B.; Sinmaz, M. A.; Tülek, F.

    2016-05-01

    Laser-induced breakdown spectroscopy (LIBS) technique is expected to be one of the most preferred techniques in archaeology research since it does not disrupt the structural and chemical form of archaeological samples, and it is considered virtually nondestructive analysis method. In this work, LIBS is used for analyses of glaze, paint, and clay of medieval ceramics collected from East Plain Cilicia, Osmaniye Province during archaeological survey. Transparent glazed and colour-painted ceramics of the Islam and Byzantine pottery traditions are analysed to detect distinctive and common features of the chemical compositions of their glazes. The spectral lines of Islamic and Byzantine glazes indicate that their structures are same. However, strontium (Sr) is determined in the transparent glaze of Islamic ceramics. Elemental composition and homogeneity of paint on one of the sample are determined by LIBS analysis. Colour changes are related with composition differences of the paint content in the archaeological ceramic. In addition, the clay classification of archaeological ceramics taken from the Yapılıpınar mounds, Taşlıhöyük mounds, and Örenşehir ancient sites is done using PCA and PLS-DA chemometric techniques. According to the results of the classification, Yapılıpınar mounds terracotta ceramics differ from those of Taşlıhöyük and Örenşehir ancient sites.

  16. Value-Added Chemicals from Animal Manure

    SciTech Connect

    Chen, Shulin; Liao, Wei; Liu, Chuanbin; Wen, Zhiyou; Kincaid, R L.; Harrison, J H.; Elliott, Douglas C.; Brown, Michael D.; Solana, Amy E.; Stevens, Don J.

    2003-12-19

    The objective of the project proposed by Washington State University (WSU) and Pacific Northwest National Laboratory (PNNL) was to develop technology for the utilization of animal manures as feedstocks to produce value-added products. These included medium-volume commodity chemicals such as glycols or diols and protein-based products such as chemicals or feed supplements. The research focused on two aspects of this approach including the analysis and treatment of the feedstock to produce intermediate chemical precursors and the aqueous phase conversion of these intermediates to chemicals and other value-added products.

  17. Dietitians and small bowel feeding tube placement.

    PubMed

    Marsland, Cheryl

    2010-06-01

    Some advanced practice nutrition support dietitians have added small bowel feeding tube placement to their scope of responsibility. This is due, in part, to the challenges of gaining early enteral access in patients with functioning GI tracts. Emerging literature supports the practice of skilled practitioners placing feeding tubes at bedside. A variety of methods can be used to place tubes at the bedside. The nutrition support dietitian must understand licensure and liability considerations to perform this invasive procedure. This article will review literature reports of dietitians placing feeding tubes and provide information on the methods used, training and competencies required, and legal issues involved. PMID:20581321

  18. Serial hepatic gene expression profiling in Angus steers during feed restriction and realimentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growing ruminants maintained under dietary restriction for extended periods will exhibit compensatory growth when reverted to ad libitum feeding. This period of compensatory growth is associated with increased feed efficiency, lower basal energy requirements, and changes in circulating concentration...

  19. Calibration of the MSL/ChemCam/LIBS Remote Sensing Composition Instrument

    NASA Technical Reports Server (NTRS)

    Wiens, R. C.; Maurice S.; Bender, S.; Barraclough, B. L.; Cousin, A.; Forni, O.; Ollila, A.; Newsom, H.; Vaniman, D.; Clegg, S.; Lasue, J. A.; Blaney, D.; DeFlores, L.; Morris, R. V.

    2011-01-01

    The ChemCam instrument suite on board the 2011 Mars Science Laboratory (MSL) Rover, Curiosity, will provide remote-sensing composition information for rock and soil samples within seven meters of the rover using a laser-induced breakdown spectroscopy (LIBS) system, and will provide context imaging with a resolution of 0.10 mradians using the remote micro-imager (RMI) camera. The high resolution is needed to image the small analysis footprint of the LIBS system, at 0.2-0.6 mm diameter. This fine scale analytical capability will enable remote probing of stratigraphic layers or other small features the size of "blueberries" or smaller. ChemCam is intended for rapid survey analyses within 7 m of the rover, with each measurement taking less than 6 minutes. Repeated laser pulses remove dust coatings and provide depth profiles through weathering layers, allowing detailed investigation of rock varnish features as well as analysis of the underlying pristine rock composition. The LIBS technique uses brief laser pulses greater than 10 MW/square mm to ablate and electrically excite material from the sample of interest. The plasma emits photons with wavelengths characteristic of the elements present in the material, permitting detection and quantification of nearly all elements, including the light elements H, Li, Be, B, C, N, O. ChemCam LIBS projects 14 mJ of 1067 nm photons on target and covers a spectral range of 240-850 nm with resolutions between 0.15 and 0.60 nm FWHM. The Nd:KGW laser is passively cooled and is tuned to provide maximum power output from -10 to 0 C, though it can operate at 20% degraded energy output at room temperature. Preliminary calibrations were carried out on the flight model (FM) in 2008. However, the detectors were replaced in 2009, and final calibrations occurred in April-June, 2010. This presentation describes the LIBS calibration and characterization procedures and results, and details plans for final analyses during rover system thermal testing

  20. AdS3: the NHEK generation

    NASA Astrophysics Data System (ADS)

    Bena, Iosif; Heurtier, Lucien; Puhm, Andrea

    2016-05-01

    It was argued in [1] that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically- {AdS}_3× {S}^3/{{Z}}_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.

  1. Shadows, currents, and AdS fields

    SciTech Connect

    Metsaev, R. R.

    2008-11-15

    Conformal totally symmetric arbitrary spin currents and shadow fields in flat space-time of dimension greater than or equal to four are studied. A gauge invariant formulation for such currents and shadow fields is developed. Gauge symmetries are realized by involving the Stueckelberg fields. A realization of global conformal boost symmetries is obtained. Gauge invariant differential constraints for currents and shadow fields are obtained. AdS/CFT correspondence for currents and shadow fields and the respective normalizable and non-normalizable solutions of massless totally symmetric arbitrary spin AdS fields are studied. The bulk fields are considered in a modified de Donder gauge that leads to decoupled equations of motion. We demonstrate that leftover on shell gauge symmetries of bulk fields correspond to gauge symmetries of boundary currents and shadow fields, while the modified de Donder gauge conditions for bulk fields correspond to differential constraints for boundary conformal currents and shadow fields. Breaking conformal symmetries, we find interrelations between the gauge invariant formulation of the currents and shadow fields, and the gauge invariant formulation of massive fields.

  2. LIBS Spectral Data for a Mixed Actinide Fuel Pellet Containing Uranium, Plutonium, Neptunium and Americium

    SciTech Connect

    Judge, Elizabeth J.; Berg, John M.; Le, Loan A.; Lopez, Leon N.; Barefield, James E.

    2012-06-18

    Laser-induced breakdown spectroscopy (LIBS) was used to analyze a mixed actinide fuel pellet containing 75% UO{sub 2}/20% PuO{sub 2}/3% AmO{sub 2}/2% NpO{sub 2}. The preliminary data shown here is the first report of LIBS analysis of a mixed actinide fuel pellet, to the authors knowledge. The LIBS spectral data was acquired in a plutonium facility at Los Alamos National Laboratory where the sample was contained within a glove box. The initial installation of the glove box was not intended for complete ultraviolet (UV), visible (VIS) and near infrared (NIR) transmission, therefore the LIBS spectrum is truncated in the UV and NIR regions due to the optical transmission of the window port and filters that were installed. The optical collection of the emission from the LIBS plasma will be optimized in the future. However, the preliminary LIBS data acquired is worth reporting due to the uniqueness of the sample and spectral data. The analysis of several actinides in the presence of each other is an important feature of this analysis since traditional methods must chemically separate uranium, plutonium, neptunium, and americium prior to analysis. Due to the historic nature of the sample fuel pellet analyzed, the provided sample composition of 75% UO{sub 2}/20% PuO{sub 2}/3% AmO{sub 2}/2% NpO{sub 2} cannot be confirm without further analytical processing. Uranium, plutonium, and americium emission lines were abundant and easily assigned while neptunium was more difficult to identify. There may be several reasons for this observation, other than knowing the exact sample composition of the fuel pellet. First, the atomic emission wavelength resources for neptunium are limited and such techniques as hollow cathode discharge lamp have different dynamics than the plasma used in LIBS which results in different emission spectra. Secondly, due to the complex sample of four actinide elements, which all have very dense electronic energy levels, there may be reactions and

  3. Probiotic Feeding Experiments with Juvenile Channel Catfish and Nile Tilapia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Probiotic microbial feed supplements are gaining wide acceptance in livestock production, and may be applicable to aquaculture production systems. We have conducted a series of experiments using commercial probiotics added to diets of juvenile channel catfish, Ictalurus punctatus (Rafinesque), and...

  4. Feeding underground: kinematics of feeding in caecilians.

    PubMed

    Herrel, Anthony; Measey, G John

    2012-11-01

    Caecilians are limbless amphibians that have evolved distinct cranial and postcranial specializations associated with a burrowing lifestyle. Observations on feeding behavior are rare and restricted to above-ground feeding in laboratory conditions. Here we report data on feeding in tunnels using both external video and X-ray recordings of caecilians feeding on invertebrate prey. Our data show feeding kinematics similar to those previously reported, including the pronounced neck bending observed during above-ground feeding. Our data illustrate, however, that caecilians may be much faster than previously suspected, with lunge speeds of up to 7 cm sec(-1). Although gape cycles are often slow (0.67 ± 0.29 sec), rapid jaw closure is observed during prey capture, with cycle times and jaw movement velocities similar to those observed in other terrestrial tetrapods. Finally, our data suggest that gape angles may be large (64.8 ± 18°) and that gape profiles are variable, often lacking distinct slow and fast opening and closing phases. These data illustrate the importance of recording naturalistic feeding behavior and shed light on how these animals are capable of capturing and processing prey in constrained underground environments. Additional data on species with divergent cranial morphologies would be needed to better understand the co-evolution between feeding, burrowing, and cranial design in caecilians. PMID:22927194

  5. Analysis of geological materials containing uranium using laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Barefield, James E.; Judge, Elizabeth J.; Campbell, Keri R.; Colgan, James P.; Kilcrease, David P.; Johns, Heather M.; Wiens, Roger C.; McInroy, Rhonda E.; Martinez, Ronald K.; Clegg, Samuel M.

    2016-06-01

    Laser induced breakdown spectroscopy (LIBS) is a rapid atomic emission spectroscopy technique that can be configured for a variety of applications including space, forensics, and industry. LIBS can also be configured for stand-off distances or in-situ, under vacuum, high pressure, atmospheric or different gas environments, and with different resolving-power spectrometers. The detection of uranium in a complex geological matrix under different measurement schemes is explored in this paper. Although many investigations have been completed in an attempt to detect and quantify uranium in different matrices at in-situ and standoff distances, this work detects and quantifies uranium in a complex matrix under Martian and ambient air conditions. Investigation of uranium detection using a low resolving-power LIBS system at stand-off distances (1.6 m) is also reported. The results are compared to an in-situ LIBS system with medium resolving power and under ambient air conditions. Uranium has many thousands of emission lines in the 200-800 nm spectral region. In the presence of other matrix elements and at lower concentrations, the limit of detection of uranium is significantly reduced. The two measurement methods (low and high resolving-power spectrometers) are compared for limit of detection (LOD). Of the twenty-one potential diagnostic uranium emission lines, seven (409, 424, 434, 435, 436, 591, and 682 nm) have been used to determine the LOD for pitchblende in a dunite matrix using the ChemCam test bed LIBS system. The LOD values determined for uranium transitions in air are 409.013 nm (24,700 ppm), 424.167 nm (23,780 ppm), 434.169 nm (24,390 ppm), 435.574 nm (35,880 ppm), 436.205 nm (19,340 ppm), 591.539 nm (47,310 ppm), and 682.692 nm (18,580 ppm). The corresponding LOD values determined for uranium transitions in 7 Torr CO2 are 424.167 nm (25,760 ppm), 434.169 nm (40,800 ppm), 436.205 nm (32,050 ppm), 591.539 nm (15,340 ppm), and 682.692 nm (29,080 ppm). The LOD values

  6. Analysis of deposited impurity material on the surface of the optical window of the Tokamak using LIBS

    NASA Astrophysics Data System (ADS)

    Singh Maurya, Gulab; Jyotsana, Aradhana; Kumar, Rohit; Kumar, Ajai; Rai, A. K.

    2014-07-01

    The emission spectra emitted from the laser-induced plasma of the optical window of Aditya Tokamak have been studied to identify the eroded materials deposited on its surface. Different layers of the window, such as the impurity deposited layer, antireflection coating and main matrix of the window material, have been identified. Laser-induced breakdown spectroscopy (LIBS) spectra of the impurity layer (first layer) shows the presence of spectral lines of Fe, Cr, Ni, Mn, Mo, Cu, C and O most of which are the components of stainless steel (SS316L) used for the fabrication of the Tokamak. LIBS spectra of the antireflection coating layer (second layer) show the spectral signature of Ca and Mg, whereas in the inner layer (last layer), the spectral lines of Al, Si and B are present. The concentrations of the impurities estimated by CF-LIBS are closely related to the constituents (major and minor) of the SS316L. Principal component analysis using LIBS data was performed to differentiate the different layers (impurity, antireflection coating and main matrix) of the window. The result of the present study demonstrates the capability of LIBS as an in-situ monitoring tool for detection and quantification of elements present in the different layers of the optical window of the Tokamak.

  7. BiopLib and BiopTools—a C programming library and toolset for manipulating protein structure

    PubMed Central

    Porter, Craig T.; Martin, Andrew C.R.

    2015-01-01

    Summary: We describe BiopLib, a mature C programming library for manipulating protein structure, and BiopTools, a set of command-line tools which exploit BiopLib. The library also provides a small number of functions for handling protein sequence and general purpose programming and mathematics. BiopLib transparently handles PDBML (XML) format and standard PDB files. BiopTools provides facilities ranging from renumbering atoms and residues to calculation of solvent accessibility. Availability and implementation: BiopLib and BiopTools are implemented in standard ANSI C. The core of the BiopLib library is a reliable PDB parser that handles alternate occupancies and deals with compressed PDB files and PDBML files automatically. The library is designed to be as flexible as possible, allowing users to handle PDB data as a simple list of atoms, or in a structured form using chains, residues and atoms. Many of the BiopTools command-line tools act as filters, taking a PDB (or PDBML) file as input and producing a PDB (or PDBML) file as output. All code is open source and documented using Doxygen. It is provided under the GNU Public Licence and is available from the authors’ web site or from GitHub. Contact: andrew@bioinf.org.uk PMID:26323716

  8. ADS pilot program Plan

    NASA Technical Reports Server (NTRS)

    Clauson, J.; Heuser, J.

    1981-01-01

    The Applications Data Service (ADS) is a system based on an electronic data communications network which will permit scientists to share the data stored in data bases at universities and at government and private installations. It is designed to allow users to readily locate and access high quality, timely data from multiple sources. The ADS Pilot program objectives and the current plans for accomplishing those objectives are described.

  9. Application Of Laser Induced Breakdown Spectroscopy (LIBS) Technique In Investigation Of Historical Metal Threads

    SciTech Connect

    Abdel-Kareem, O.; Khedr, A.; Abdelhamid, M.; Harith, M. A.

    2009-09-27

    Analysis of the composition of an object is a necessary step in the documentation of the properties of this object for estimating its condition. Also this is an important task for establishing an appropriate conservation treatment of an object or to follow up the result of the application of the suggested treatments. There has been an important evolution in the methods used for analysis of metal threads since the second half of the twentieth century. Today, the main considerations of selecting a method are based on the diagnostic power, representative sampling, reproducibility, destructive nature/invasiveness of analysis and accessibility to the appropriate instrument. This study aims at evaluating the usefulness of the use of Laser Induced Breakdown Spectroscopy (LIBS) Technique for analysis of historical metal threads. In this study various historical metal threads collected from different museums were investigated using (LIBS) technique. For evaluating usefulness of the suggested analytical protocol of this technique, the same investigated metal thread samples were investigated with Scanning Electron Microscope (SEM) with energy-dispersive x-ray analyzer (EDX) which is reported in conservation field as the best method, to determine the chemical composition, and corrosion of investigated metal threads. The results show that all investigated metal threads in the present study are too dirty, strongly damaged and corroded with different types of corrosion products. Laser Induced Breakdown Spectroscopy (LIBS) Technique is considered very useful technique that can be used safely for investigating historical metal threads. It is, in fact, very useful tool as a noninvasive method for analysis of historical metal threads. The first few laser shots are very useful for the investigation of the corrosion and dirt layer, while the following shots are very useful and effective for investigating the coating layer. Higher number of laser shots are very useful for the main

  10. Validation of libRadtran and SBDART models under different aerosol conditions

    NASA Astrophysics Data System (ADS)

    Obregón, M. A.; Serrano, A.; Costa, M. J.; Silva, A. M.

    2015-12-01

    This study is aimed at analyzing the performance of the radiative transfer models libRadtran and SBDART for estimating the shortwave (285-2800 nm) irradiance under different aerosol conditions. For that purpose, measurements of downward irradiance at the Earth s surface in Évora and the corresponding model simulations have been compared for six selected days (03-08-2003, 15-08-2004, 24-08-2004, 18-07-2005, 19-08-2007 and 17-05-2010). The comparison between measured and simulated values shows a highly significant correlation, with determination coefficient between 0.999 and 1 for both models and slope very close to unity (between 0.992±0.004 and 1.017±0.003 for libRadtran, and between 0.997±0.004 and 1.024±0.002 for SBDART), supporting the validity of the models in the estimation of irradiance in the shortwave spectral range. Relative differences between the simulated and measured irradiances with respect to the measured values have also been calculated, being most of the differences for the six days lower than 0.2%. These small differences could be associated with experimental errors in the measurements as well as uncertainties in the input values given to the models, particularly those related with the aerosol properties. Also, relative differences between models have been calculated, obtaining values lower than 0.1%. SBDART model slightly overestimates the libRadtran simulations. The notably good agreement between simulated and measured irradiances indicates that both models can be used to estimate irradiance, provided that the models are fed with highly reliable-quality data.

  11. Monitoring of heavy metal particle emission in the exhaust duct of a foundry using LIBS.

    PubMed

    Dutouquet, C; Gallou, G; Le Bihan, O; Sirven, J B; Dermigny, A; Torralba, B; Frejafon, E

    2014-09-01

    Heavy metals have long been known to be detrimental to human health and the environment. Their emission is mainly considered to occur via the atmospheric route. Most of airborne heavy metals are of anthropogenic origin and produced through combustion processes at industrial sites such as incinerators and foundries. Current regulations impose threshold limits on heavy metal emissions. The reference method currently implemented for quantitative measurements at exhaust stacks consists of on-site sampling of heavy metals on filters for the particulate phase (the most prominent and only fraction considered in this study) prior to subsequent laboratory analysis. Results are therefore known only a few days after sampling. Stiffer regulations require the development of adapted tools allowing automatic, on-site or even in-situ measurements with temporal resolutions. The Laser-Induced Breakdown Spectroscopy (LIBS) technique was deemed as a potential candidate to meet these requirements. On site experiments were run by melting copper bars and monitoring emission of this element in an exhaust duct at a pilot-scale furnace in a French research center dedicated to metal casting. Two approaches designated as indirect and direct analysis were broached in these experiments. The former corresponds to filter enrichment prior to subsequent LIBS interrogation whereas the latter entails laser focusing right through the aerosol for detection. On-site calibration curves were built and compared with those obtained at laboratory scale in order to investigate possible matrix and analyte effects. Eventually, the obtained results in terms of detection limits and quantitative temporal monitoring of copper emission clearly emphasize the potentialities of the direct LIBS measurements. PMID:24913859

  12. Investigation of Historical Metal Objects Using Laser Induced Breakdown Spectroscopy (libs) Technique

    NASA Astrophysics Data System (ADS)

    Abdel-Kareem, O.; Ghoneim, M.; Harith, M. A.

    2011-09-01

    Analysis of metal objects is a necessary step for establishing an appropriate conservation treatment of an object or to follow up the application's result of the suggested treatments. The main considerations on selecting a method that can be used in investigation and analysis of metal objects are based on the diagnostic power, representative sampling, reproducibility, destructive nature/invasiveness of analysis and accessibility to the appropriate instrument. This study aims at evaluating the usefulness of the use of Laser Induced Breakdown Spectroscopy (LIBS) Technique for analysis of historical metal objects. In this study various historical metal objects collected from different museums and excavations in Egypt were investigated using (LIBS) technique. For evaluating usefulness of the suggested analytical protocol of this technique, the same investigated metal objects were investigated by other methods such as Scanning Electron Microscope with energy-dispersive x-ray analyzer (SEM-EDX) and X-ray Diffraction (XRD). This study confirms that Laser Induced Breakdown Spectroscopy (LIBS) Technique is considered very useful technique that can be used safely for investigating historical metal objects. LIBS analysis can quickly provide information on the qualitative and semi-quantitative elemental content of different metal objects and their characterization and classification. It is practically non-destructive technique with the critical advantage of being applicable in situ, thereby avoiding sampling and sample preparations. It is can be dependable, satisfactory and effective method for low cost study of archaeological and historical metals. But we have to take into consideration that the corrosion of metal leads to material alteration and possible loss of certain metals in the form of soluble salts. Certain corrosion products are known to leach out of the object and therefore, their low content does not necessarily reflect the composition of the metal at the time of

  13. zorder-lib: Library API for Z-Order Memory Layout

    SciTech Connect

    Nowell, Lucy; Edward W. Bethel

    2015-04-01

    This document describes the motivation for, elements of, and use of the zorder-lib, a library API that implements organization of and access to data in memory using either a-order (also known as "row-major" order) or z-order memory layouts. The primary motivation for this work is to improve the performance of many types of data- intensive codes by increasing both spatial and temporal locality of memory accesses. The basic idea is that the cost associated with accessing a datum is less when it is nearby in either space or time.

  14. Lattice defects and recombination processes in non-linear crystals LiB3O5

    NASA Astrophysics Data System (ADS)

    Ogorodnikov, I. N.; Kruzhalov, A. V.; Porotnikov, A. V.; Yakovlev, Yu. V.

    The paper presents the results of a study of kinetics of the recombination processes in crystals LiB3O5 (LBO) obtained by the use of time-resolved luminescence and optical absorption spectroscopy. It was revealed that the observed peculiarities of the recombination processes in LBO are due to a participation of the trapped electron (B2+) and hole (O-) centres. In the framework of a model of the competing trapped hole centres the time dependence of both transient optical absorption and luminescence as well as their temperature dependencies was interpreted.

  15. Investigation of historical metal objects using Laser Induced Breakdown Spectroscopy (LIBS) technique

    SciTech Connect

    Abdel-Kareem, O.; Ghoneim, M.; Harith, M. A.

    2011-09-22

    Analysis of metal objects is a necessary step for establishing an appropriate conservation treatment of an object or to follow up the application's result of the suggested treatments. The main considerations on selecting a method that can be used in investigation and analysis of metal objects are based on the diagnostic power, representative sampling, reproducibility, destructive nature/invasiveness of analysis and accessibility to the appropriate instrument. This study aims at evaluating the usefulness of the use of Laser Induced Breakdown Spectroscopy (LIBS) Technique for analysis of historical metal objects. In this study various historical metal objects collected from different museums and excavations in Egypt were investigated using (LIBS) technique. For evaluating usefulness of the suggested analytical protocol of this technique, the same investigated metal objects were investigated by other methods such as Scanning Electron Microscope with energy-dispersive x-ray analyzer (SEM-EDX) and X-ray Diffraction (XRD). This study confirms that Laser Induced Breakdown Spectroscopy (LIBS) Technique is considered very useful technique that can be used safely for investigating historical metal objects. LIBS analysis can quickly provide information on the qualitative and semi-quantitative elemental content of different metal objects and their characterization and classification. It is practically non-destructive technique with the critical advantage of being applicable in situ, thereby avoiding sampling and sample preparations. It is can be dependable, satisfactory and effective method for low cost study of archaeological and historical metals. But we have to take into consideration that the corrosion of metal leads to material alteration and possible loss of certain metals in the form of soluble salts. Certain corrosion products are known to leach out of the object and therefore, their low content does not necessarily reflect the composition of the metal at the time of

  16. Calibrating the ChemCam LIBS for carbonate minerals on Mars

    SciTech Connect

    Wiens, Roger C; Clegg, Samuel M; Ollila, Ann M; Barefield, James E; Lanza, Nina; Newsom, Horton E

    2009-01-01

    The ChemCam instrument suite on board the NASA Mars Science Laboratory (MSL) rover includes the first LIBS instrument for extraterrestrial applications. Here we examine carbonate minerals in a simulated martian environment using the LIDS technique in order to better understand the in situ signature of these materials on Mars. Both chemical composition and rock type are determined using multivariate analysis (MVA) techniques. Composition is confirmed using scanning electron microscopy (SEM) techniques. Our initial results suggest that ChemCam can recognize and differentiate between carbonate materials on Mars.

  17. Calibrating the ChemCam LIBS for Carbonate Minerals on Mars

    DOE R&D Accomplishments Database

    Wiens, Roger C.; Clegg, Samuel M.; Ollila, Ann M.; Barefield, James E.; Lanza, Nina; Newsom, Horton E.

    2009-01-01

    The ChemCam instrument suite on board the NASA Mars Science Laboratory (MSL) rover includes the first LIBS instrument for extraterrestrial applications. Here we examine carbonate minerals in a simulated martian environment using the LIDS technique in order to better understand the in situ signature of these materials on Mars. Both chemical composition and rock type are determined using multivariate analysis (MVA) techniques. Composition is confirmed using scanning electron microscopy (SEM) techniques. Our initial results suggest that ChemCam can recognize and differentiate between carbonate materials on Mars.

  18. Relationship between LIBS Ablation and Pit Volume for Geologic Samples: Applications for in situ Absolute Geochronology

    NASA Technical Reports Server (NTRS)

    Devismes, D.; Cohen, Barbara A.

    2014-01-01

    In planetary sciences, in situ absolute geochronology is a scientific and engineering challenge. Currently, the age of the Martian surface can only be determined by crater density counting. However this method has significant uncertainties and needs to be calibrated with absolute ages. We are developing an instrument to acquire in situ absolute geochronology based on the K-Ar method. The protocol is based on the laser ablation of a rock by hundreds of laser pulses. Laser Induced Breakdown Spectroscopy (LIBS) gives the potassium content of the ablated material and a mass spectrometer (quadrupole or ion trap) measures the quantity of 40Ar released. In order to accurately measure the quantity of released 40Ar in cases where Ar is an atmospheric constituent (e.g., Mars), the sample is first put into a chamber under high vacuum. The 40Arquantity, the concentration of K and the estimation of the ablated mass are the parameters needed to give the age of the rocks. The main uncertainties with this method are directly linked to the measures of the mass (typically some µg) and of the concentration of K by LIBS (up to 10%). Because the ablated mass is small compared to the mass of the sample, and because material is redeposited onto the sample after ablation, it is not possible to directly measure the ablated mass. Our current protocol measures the ablated volume and estimates the sample density to calculate ablated mass. The precision and accuracy of this method may be improved by using knowledge of the sample's geologic properties to predict its response to laser ablation, i.e., understanding whether natural samples have a predictable relationship between laser energy deposited and resultant ablation volume. In contrast to most previous studies of laser ablation, theoretical equations are not highly applicable. The reasons are numerous, but the most important are: a) geologic rocks are complex, polymineralic materials; b) the conditions of ablation are unusual (for example

  19. Electronic structure of a LiB 3 O 5 nonlinear optical crystal

    NASA Astrophysics Data System (ADS)

    Kuznetsov, A. Yu; Sobolev, A. B.; Ogorodnikov, I. N.; Kruzhalov, A. V.

    1995-12-01

    The electronic bands of a LiB 3 O 5 (LBO) crystal with excellent nonlinear optical properties have been studied using the scattered-wave method in embedded-cluster model. Calculations were carried out for a [B 3 O 7]5? cluster, as this anionic group is the crystal basic structural unit. The interpretation of experimental photoemission spectra is based on electronic structure cluster calculations. From calculation performed, it follows that the contribution of trigonal and tetrahedral boron-oxygen groups dominates in the electronic structure of LBO, the contribution of 2p-boron states is immaterial.

  20. Modi: a new mobile instrument for in situ standardless LIBS analysis of cultural heritage

    NASA Astrophysics Data System (ADS)

    Cristoforetti, Gabriele; Legnaioli, Stefano; Palleschi, Vincenzo; Pardini, Lorenzo; Salvetti, Azenio; Tognoni, Elisabetta

    2005-06-01

    Laser-Induced Breakdown Spectroscopy (LIBS) is a promising technique for in-situ analysis of Cultural Heritage. The potential of this technique for accurate quantitative analysis could be greatly improved using an innovative experimental setup - based on the use of two laser pulses suitably retarded - and analyzing the results with a standard-less procedure which overcomes the problems related to matrix effects. A new mobile instrument for Cultural Heritage analysis, developed at the Applied Laser Spectroscopy Laboratory in Pisa, is presented, and some experimental results are given.

  1. Remote Raman - laser induced breakdown spectroscopy (LIBS) geochemical investigation under Venus atmospheric conditions

    SciTech Connect

    Clegg, Sanuel M; Barefield, James E; Humphries, Seth D; Wiens, Roger C; Vaniman, D. T.; Sharma, S. K.; Misra, A. K.; Dyar, M. D.; Smrekar, S. E.

    2010-12-13

    The extreme Venus surface temperatures ({approx}740 K) and atmospheric pressures ({approx}93 atm) create a challenging environment for surface missions. Scientific investigations capable of Venus geochemical observations must be completed within hours of landing before the lander will be overcome by the harsh atmosphere. A combined remote Raman - LIBS (Laser Induced Breakdown Spectroscopy) instrument is capable of accomplishing the geochemical science goals without the risks associated with collecting samples and bringing them into the lander. Wiens et al. and Sharma et al. demonstrated that both analytical techniques can be integrated into a single instrument capable of planetary missions. The focus of this paper is to explore the capability to probe geologic samples with Raman - LIBS and demonstrate quantitative analysis under Venus surface conditions. Raman and LIBS are highly complementary analytical techniques capable of detecting both the mineralogical and geochemical composition of Venus surface materials. These techniques have the potential to profoundly increase our knowledge of the Venus surface composition, which is currently limited to geochemical data from Soviet Venera and VEGA landers that collectively suggest a surface composition that is primarily tholeiitic basaltic with some potentially more evolved compositions and, in some locations, K-rich trachyandesite. These landers were not equipped to probe the surface mineralogy as can be accomplished with Raman spectroscopy. Based on the observed compositional differences and recognizing the imprecise nature of the existing data, 15 samples were chosen to constitute a Venus-analog suite for this study, including five basalts, two each of andesites, dacites, and sulfates, and single samples of a foidite, trachyandesite, rhyolite, and basaltic trachyandesite under Venus conditions. LIBS data reduction involved generating a partial least squares (PLS) model with a subset of the rock powder standards to

  2. Breastfeeding vs. Formula Feeding

    MedlinePlus

    ... breastfeed your baby or bottle feed using infant formula . Health experts agree that breastfeeding is the healthiest ... is hungry. You do not need to make formula before feeding, worry about clean water, or carry ...

  3. Gastrostomy feeding tube - bolus

    MedlinePlus

    ... jaw muscles. Feeding Your Child with the Gravity Method Your provider will show you the best way ... the button. Feeding Your Child with the Syringe Method Your provider will teach you the best way ...

  4. Application of LIBS and TMA for the determination of combustion predictive indices of coals and coal blends

    NASA Astrophysics Data System (ADS)

    Ctvrtnickova, T.; Mateo, M. P.; Yañez, A.; Nicolas, G.

    2011-04-01

    Presented work brings results of Laser-Induced Breakdown Spectroscopy (LIBS) and Thermo-Mechanical Analysis (TMA) of coals and coal blends used in coal fired power plants all over Spain. Several coal specimens, its blends and corresponding laboratory ash were analyzed by mentioned techniques and results were compared to standard laboratory methods. The indices of slagging, which predict the tendency of coal ash deposition on the boiler walls, were determined by means of standard chemical analysis, LIBS and TMA. The optimal coal suitable to be blended with the problematic national lignite coal was suggested in order to diminish the slagging problems. Used techniques were evaluated based on the precision, acquisition time, extension and quality of information they could provide. Finally, the applicability of LIBS and TMA to the successful calculation of slagging indices is discussed and their substitution of time-consuming and instrumentally difficult standard methods is considered.

  5. Laser Induced Breakdown Spectroscopy (LIBS) detection of heavy metal using a cone penetrometer: System design and field investigation results

    SciTech Connect

    Miles, B.H.; Cortes, J.; Cespedes, E.R.

    1997-12-31

    U.S. Army Engineer Waterways Experiment Station (WES) investigators have designed, fabricated and field tested a cone penetrometer sensor based on Laser Induced Breakdown Spectroscopy (LIBS). The patented LIBS penetrometer design presented here is a useful tool in the detection, identification and delineation of heavy metals in soils in the vadose zone. The LIBS penetrometer is forced into the ground using a hydraulic ram system mounted within the Site Characterization and Analysis Penetrometer System (SCAPS) truck. The probe design relies on a recessed window geometry to avoid output window damage and a 80 millijoule Nd:YAG laser inside the probe to create the plasma. The probe design is discussed with particular emphasis on design tradeoffs, strengths and limitations of this design.

  6. Effect of diet grinding and pelleting fed either dry or liquid feed on dry matter and pH in the stomach of pigs and the development of gastric ulcers.

    PubMed

    Mösseler, A; Wintermann, M; Sander, S J; Kamphues, J

    2012-12-01

    The physical form of diets has a marked impact on the development of gastric ulcers in pigs. Earlier studies showed effects of fine grinding and pelleting on the integrity of gastric mucosa as well as on local intragastric milieu. This study was conducted to evaluate the effects of dry or liquid feeding on intragastric milieu (DM and pH) in pigs. The 23 piglets were housed individually and fed with test diets and water ad lib for 6 wk. Both experimental diets [coarsely ground diet fed as mash (CM) vs. finely ground pelleted diet (FP)] were identical in ingredients (39.5% wheat, 34% barley, 20% soybean meal) and chemical composition and were either offered dry or in liquid (25% DM) form. At the end of the trial the animals were slaughtered; the stomach was removed and samples were taken from different localizations. Feeding diets dry or liquid had no effect on the pH (P > 0.05). The diet noticeably affected the gastric content. The FP diets resulted in a more liquid chyme (P < 0.05), and the intragastric pH did not differ between regions. Feeding CM caused marked effects of localization regarding pH (highest values: pars nonglandularis; lowest values: fundus). None of the pigs fed CM showed signs of gastric ulcers, but the score was markedly higher (P < 0.05) when pigs were fed FP. Therefore the predominant factor for development of gastric ulcers seems to be the structure (particle size) of the diet. PMID:23365374

  7. Incorporation of support vector machines in the LIBS toolbox for sensitive and robust classification amidst unexpected sample and system variability

    PubMed Central

    ChariDingari, Narahara; Barman, Ishan; Myakalwar, Ashwin Kumar; Tewari, Surya P.; Kumar, G. Manoj

    2012-01-01

    Despite the intrinsic elemental analysis capability and lack of sample preparation requirements, laser-induced breakdown spectroscopy (LIBS) has not been extensively used for real world applications, e.g. quality assurance and process monitoring. Specifically, variability in sample, system and experimental parameters in LIBS studies present a substantive hurdle for robust classification, even when standard multivariate chemometric techniques are used for analysis. Considering pharmaceutical sample investigation as an example, we propose the use of support vector machines (SVM) as a non-linear classification method over conventional linear techniques such as soft independent modeling of class analogy (SIMCA) and partial least-squares discriminant analysis (PLS-DA) for discrimination based on LIBS measurements. Using over-the-counter pharmaceutical samples, we demonstrate that application of SVM enables statistically significant improvements in prospective classification accuracy (sensitivity), due to its ability to address variability in LIBS sample ablation and plasma self-absorption behavior. Furthermore, our results reveal that SVM provides nearly 10% improvement in correct allocation rate and a concomitant reduction in misclassification rates of 75% (cf. PLS-DA) and 80% (cf. SIMCA)-when measurements from samples not included in the training set are incorporated in the test data – highlighting its robustness. While further studies on a wider matrix of sample types performed using different LIBS systems is needed to fully characterize the capability of SVM to provide superior predictions, we anticipate that the improved sensitivity and robustness observed here will facilitate application of the proposed LIBS-SVM toolbox for screening drugs and detecting counterfeit samples as well as in related areas of forensic and biological sample analysis. PMID:22292496

  8. LIBS: a new versatile field-deployable real-time detector system with potential for landmine detection

    NASA Astrophysics Data System (ADS)

    Harmon, Russell S.; De Lucia, Frank C.; Winkel, Raymond J., Jr.; LaPointe, Aaron; Grossman, Scott L.; McNesby, Kevin L.; Miziolek, Andrzej W.

    2003-09-01

    Laser Induced Breakdown Spectroscopy (LIBS) is an atomic emission spectroscopic technique that utilizes a pulsed laser to create a microplasma on the target together with an array spectrometer to capture the transient light for elemental identification and quantification. LIBS has certain important characteristics that make it a very attractive sensor technology for military uses. Such attributes include that facts that LIBS (1) is relatively simple and straightforward, (2) requires no sample preparation, (3) generates a real-time response, and (4) only engages a very small sample (pg-ng) of matter in each laser shot and microplasma event, (5) has inherent high sensitivity, and (6) responds to all forms of unknowns, and, therefore, is particularly suited for the sensing of dangerous materials. Additionally, a LIBS sensor system can be inexpensive, configured to be man-portable, and designed for both in-situ point sensing and remote stand-off detection with distances of up to 20-25 meters. Broadband LIBS results covering the spectral region from 200-970 nm acquired at the Army Research Laboratory (ARL) under laboratory conditions for a variety of landmine casings and explosive materials. This data will illustrate the potential that LIBS has to be developed into a hand-deployable device that could be utilized as a confirmatory sensor in landmine detection. The concept envisioned is a backpack-size system in which an eyesafe micro-laser is contained in the handle of a deminer's probe and light is delivered and collected through an optical fiber in the tapered tip of the probe. In such a configuration, analyses can be made readily by touching the buried object that one is interested in identifying.

  9. Radiation resistance of nonlinear LiB3O5 crystals: optical properties

    NASA Astrophysics Data System (ADS)

    Ogorodnikov, I. N.; Kruzhalov, A. V.; Porotnikov, A. V.

    1997-02-01

    This paper presents the results of study of the radiation stability of LiB3O5 (LBO) crystals with regard to optical properties. LBO crystals of the high optical quality were studied under action of an electron beam with energy of 0.2 - 10 MeV, x-rays, and polarized synchrotron radiation of a high intensity. Both the trapped electron (B2) and hole (O-) centers were revealed and their optical manifestations were studied in detail. In particular, the strong radiation-induced optical absorption band at lambda equals 306 nm, extending up to the spectral region of the second harmonic (at about 532 nm), was attributed to the optical transitions inside the O- center. The accumulation of defects over the dose region between 1010 and 5 multiplied by 1016 electrons per cm2 was measured. The accumulation curve at 77 K exhibits two well-defined flux regions: 1010-1014 and 1014- 1016 electrons per cm2. The paper discusses the origin of radiation degradation of LiB3O5 optical properties.

  10. Laser-induced breakdown spectroscopy (LIBS) for detection of ammonium nitrate in soils

    NASA Astrophysics Data System (ADS)

    Díaz, Daniel; Hahn, David W.; Molina, Alejandro

    2009-05-01

    The extensive use of improvised explosive devices (IED) by irregular armed groups in Colombia has posed a threat, not only to the Colombian regular army but to the civilian population. It is expected that in future years, after an eventual cease fire, humanitarian missions for IED clearance will be fundamental to secure safe transit of people and goods, particularly in Colombian rural areas. The clandestine nature of IEDs preparation in Colombia yielded a rather diverse nature of these irregular weapons. Although, some have metal parts such as nails and shrapnel, others are metal-free devices in which detonation is obtained by chemical means. Despite this variability in IEDs design, one thing that is common in IEDs preparation is the use of significant amounts of ANFO (ammonium nitrate (AN), fuel oil (FO)) in their construction. The goal of this work was to identify AN and FO in soils using LIBS. Experiments showed the ability of LIBS to identify the presence of AN based on Hα (656.3 nm) and Hβ (486.1 nm) emission lines. It was not possible to identify FO mixed with soils in the spectral windows studied. FO caused a reduction on spark intensity on the samples. This would represent a challenge for identification of chemical compounds in wet soils. Potential interferences with fertilizers are discussed as well.

  11. Study of the dynamical behavior of the LIBS plasma under conditions of low atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Jijón, D.; Costa Vera, C.

    2011-09-01

    A new arrangement of 3 Langmuir probes to evaluate the electric potential and estimate the electron temperature in the LIBS plasma is introduced in this work. It consists of three nickel meshes (95% of transparency) on a basis for the sample in a vacuum chamber. The sample (a 50 cents coin) was analyzed at 9 different pressures (0.2, 0.4, 0.6, 0.8, 1, 2, 4, 6, 8 Torr). Measurements were made of the voltage signal induced in the electrodes relative to one another and to the sample. Information about the on-time and the duration of the plasma under the decreased pressure conditions can be extracted from these signals, which could in principle, be also correlated with the velocity of expansion of the plasma and the establishment of thermodynamical equilibrium in the system plasma-background gas. Additionally, we photographed the emitted light by LIBS plasma at maximum extension at different pressures by means of two digital cameras at the right angles to one another and to the laser beam. In each case, the expanded plasma contour was mathematically analyzed. In particular, the area of the plasma plume as recorded with the cameras was found to follow a simple relationship with the background pressure in a way not different from an ideal gas.

  12. Less is more: Avoiding the LIBS dimensionality curse through judicious feature selection for explosive detection

    PubMed Central

    Kumar Myakalwar, Ashwin; Spegazzini, Nicolas; Zhang, Chi; Kumar Anubham, Siva; Dasari, Ramachandra R.; Barman, Ishan; Kumar Gundawar, Manoj

    2015-01-01

    Despite its intrinsic advantages, translation of laser induced breakdown spectroscopy for material identification has been often impeded by the lack of robustness of developed classification models, often due to the presence of spurious correlations. While a number of classifiers exhibiting high discriminatory power have been reported, efforts in establishing the subset of relevant spectral features that enable a fundamental interpretation of the segmentation capability and avoid the ‘curse of dimensionality’ have been lacking. Using LIBS data acquired from a set of secondary explosives, we investigate judicious feature selection approaches and architect two different chemometrics classifiers –based on feature selection through prerequisite knowledge of the sample composition and genetic algorithm, respectively. While the full spectral input results in classification rate of ca.92%, selection of only carbon to hydrogen spectral window results in near identical performance. Importantly, the genetic algorithm-derived classifier shows a statistically significant improvement to ca. 94% accuracy for prospective classification, even though the number of features used is an order of magnitude smaller. Our findings demonstrate the impact of rigorous feature selection in LIBS and also hint at the feasibility of using a discrete filter based detector thereby enabling a cheaper and compact system more amenable to field operations. PMID:26286630

  13. Less is more: Avoiding the LIBS dimensionality curse through judicious feature selection for explosive detection

    NASA Astrophysics Data System (ADS)

    Kumar Myakalwar, Ashwin; Spegazzini, Nicolas; Zhang, Chi; Kumar Anubham, Siva; Dasari, Ramachandra R.; Barman, Ishan; Kumar Gundawar, Manoj

    2015-08-01

    Despite its intrinsic advantages, translation of laser induced breakdown spectroscopy for material identification has been often impeded by the lack of robustness of developed classification models, often due to the presence of spurious correlations. While a number of classifiers exhibiting high discriminatory power have been reported, efforts in establishing the subset of relevant spectral features that enable a fundamental interpretation of the segmentation capability and avoid the ‘curse of dimensionality’ have been lacking. Using LIBS data acquired from a set of secondary explosives, we investigate judicious feature selection approaches and architect two different chemometrics classifiers -based on feature selection through prerequisite knowledge of the sample composition and genetic algorithm, respectively. While the full spectral input results in classification rate of ca.92%, selection of only carbon to hydrogen spectral window results in near identical performance. Importantly, the genetic algorithm-derived classifier shows a statistically significant improvement to ca. 94% accuracy for prospective classification, even though the number of features used is an order of magnitude smaller. Our findings demonstrate the impact of rigorous feature selection in LIBS and also hint at the feasibility of using a discrete filter based detector thereby enabling a cheaper and compact system more amenable to field operations.

  14. Design and construction of Q-switched Nd:YAG laser system for LIBS measurements

    NASA Astrophysics Data System (ADS)

    Elsayed, Khaled.; Imam, Hisham; Harfoosh, Amro; Hassebo, Yasser; Elbaz, Yasser; Aziz, Mouayed; Mansour, Mohy

    2012-02-01

    A passive, Q-switched pulsed, Nd:YAG laser system was designed and built, which can provide a potential compact robust laser source for portable laser induced breakdown spectroscopy systems. The developed laser system operates at 1064 nm. Each laser shot contains a train of pulses having maximum total output energy of 170 mJ. The number of pulses varies from 1-6 pulses in each laser shot depending on the pump energy. The pulse width of each pulse ranges from 20 to 30 ns. The total duration of the output pulse train is within 300 μs. The multi-pulse nature of the laser shots was employed to enhance the LIBS signal. To validate the system, LIBS measurements and analysis were performed on ancient ceramic samples collected from Al-Fustat excavation in Old Cairo. The samples belong to different Islamic periods in Egypt history. The results obtained are highly indicative that useful information can be provided to archeologists for use in restoring and repairing of precious archeological objects.

  15. LiB 3O 5 crystal structure at 20, 227 and 377 °C

    NASA Astrophysics Data System (ADS)

    Shepelev, Yu. F.; Bubnova, R. S.; Filatov, S. K.; Sennova, N. A.; Pilneva, N. A.

    2005-10-01

    Crystal structure of LiB 3O 5 (a framework of [B 3O 5] - rings and Li atoms located in interspaces) was refined at high temperatures using single-crystal X-ray diffraction, Mo Kα-radiation, anharmonic approximation, orthorhombic; Pna2 1; Z=4; 20 °C ( a=8.444, b=7.378, c=5.146 Å, 1411 F( hkl), R=0.022); 227 °C ( a=8.616, b=7.433, c=5.063 Å, 1336 F( hkl), R=0.026), 377 °C ( a=8.746, b=7.480, c=5.013 Å, 1193 F( hkl), R=0.035). A high mobility of Li atoms and their highly asymmetric vibrations are revealed. Ellipsoid of Li thermal vibrations is oviform. Li is shifted on heating to 0.26 Å mainly along a-axis causing high thermal expansion in this direction; Li temperature factors are multiplied by 4 on heating. Rigid boron-oxygen groups in LiB 3O 5 remain practically stable on heating similar to α-Na 2B 8O 13 and α-CsB 5O 8. At the same time these groups rotate relative to each other like hinges leading to extremely anisotropic thermal expansion ( α a=101, α b=31, α c=-71, α v=60×10 -6 °C -1, 20-530 °C, HTXRPD data).

  16. Measuring lanthanide concentrations in molten salt using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Weisberg, Arel; Lakis, Rollin E; Simpson, Michael F; Horowitz, Leo; Craparo, Joseph

    2014-01-01

    The versatility of laser-induced breakdown spectroscopy (LIBS) as an analytical method for high-temperature applications was demonstrated through measurement of the concentrations of the lanthanide elements europium (Eu) and praseodymium (Pr) in molten eutectic lithium chloride-potassium chloride (LiCl-KCl) salts at a temperature of 500 °C. Laser pulses (1064 nm, 7 ns, 120 mJ/pulse) were focused on the top surface of the molten salt samples in a laboratory furnace under an argon atmosphere, and the resulting LIBS signals were collected using a broadband Echelle-type spectrometer. Partial least squares (PLS) regression using leave-one-sample-out cross-validation was used to quantify the concentrations of Eu and Pr in the samples. The root mean square error of prediction (RMSEP) for Eu was 0.13% (absolute) over a concentration range of 0-3.01%, and for Pr was 0.13% (absolute) over a concentration range of 0-1.04%. PMID:25226247

  17. Less is more: Avoiding the LIBS dimensionality curse through judicious feature selection for explosive detection.

    PubMed

    Kumar Myakalwar, Ashwin; Spegazzini, Nicolas; Zhang, Chi; Kumar Anubham, Siva; Dasari, Ramachandra R; Barman, Ishan; Kumar Gundawar, Manoj

    2015-01-01

    Despite its intrinsic advantages, translation of laser induced breakdown spectroscopy for material identification has been often impeded by the lack of robustness of developed classification models, often due to the presence of spurious correlations. While a number of classifiers exhibiting high discriminatory power have been reported, efforts in establishing the subset of relevant spectral features that enable a fundamental interpretation of the segmentation capability and avoid the 'curse of dimensionality' have been lacking. Using LIBS data acquired from a set of secondary explosives, we investigate judicious feature selection approaches and architect two different chemometrics classifiers -based on feature selection through prerequisite knowledge of the sample composition and genetic algorithm, respectively. While the full spectral input results in classification rate of ca.92%, selection of only carbon to hydrogen spectral window results in near identical performance. Importantly, the genetic algorithm-derived classifier shows a statistically significant improvement to ca. 94% accuracy for prospective classification, even though the number of features used is an order of magnitude smaller. Our findings demonstrate the impact of rigorous feature selection in LIBS and also hint at the feasibility of using a discrete filter based detector thereby enabling a cheaper and compact system more amenable to field operations. PMID:26286630

  18. [Real-time, quantitative analysis of multi-elements in liquid steel by LIBS].

    PubMed

    Chen, Kai; Lu, Ji-dong; Li, Jun-yan

    2011-03-01

    The technique of laser induced breakdown spectroscopy (LIBS) was applied to analyze the composition of liquid steel. The results of research indicated that oxidation of liquid steel on the surface could be avoided because the argon and the plasma signal was enhanced at the same time. The surface of liquid steel was excited by high-energy pulse laser and plasma was formed in argon atmosphere. The spectral signal was collected with a multi-channel CCD spectrometer when the plasma cooled off and relevant information about the composition of samples was obtained. The characteristic spectral lines of analyzed elements were selected according to the selecting principle of line in LIBS and the calibration curves of major alloying elements Mn, Si and Cr were constructed. The degrees of linear fitting were all more than 0. 925 and the limit of detection of Mn, Si and Cr were 75.7, 23.8 and 724.5 microg x g(-1), respectively. PMID:21595248

  19. Ten Years of LibQual: A Study of Qualitative and Quantitative Survey Results at the University of Mississippi 2001-2010

    ERIC Educational Resources Information Center

    Greenwood, Judy T.; Watson, Alex P.; Dennis, Melissa

    2011-01-01

    This article analyzes quantitative adequacy gap scores and coded qualitative comments from LibQual surveys at the University of Mississippi from 2001 to 2010, looking for relationships between library policy changes and LibQual results and any other trends that emerged. Analysis found no relationship between changes in policy and survey results…

  20. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Uranium feed; natural uranium feed...) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The term uranium feed or natural uranium feed means natural uranium in the form of UF6 suitable for...

  1. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium feed; natural uranium feed...) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The term uranium feed or natural uranium feed means natural uranium in the form of UF6 suitable for...

  2. Development of a multipurpose feed enzyme analyzer to estimate and evaluate the profitability of using feed enzyme preparations for poultry.

    PubMed

    Zhang, Z; Marquardt, R R; Guenter, W; Crow, G H

    2001-11-01

    Previous studies have demonstrated that a log-linear equation could accurately predict chick performance when a feed enzyme was added to a diet and that the slope of the equation provided a measure of the efficacy of different enzymes. The objective of the study was to develop a software package, a Multipurpose Feed Enzyme Analyzer (MPFEA), based on an equation designed to evaluate the profitability of using feed enzymes. A high correlation between the efficacy of different feed enzymes (B values, the slopes of the equations) and the maximal profits was obtained when feed enzymes were added to a barley-based diet (r2 = 0.99, P < 0.0005). In contrast, there was a low correlation between the B values and the maximal profits when a feed enzyme was added to different cereal-based diets (r2 = 0.61, P = 0.2171). It appeared that there is not always a close association between efficacy of an enzyme when added to different cereal-based diets and the corresponding profitability. The MPFEA was highly versatile, as any combination of inputs such as the amounts of a feed enzyme and a substituted cereal required to yield a profit level could be determined. In conclusion, the MPFEA can accurately evaluate profitability of using different feed enzymes; select the most profitable cereal for a given feed enzyme; determine the optimal amounts of a feed enzyme, a cereal, or both; and even estimate the alternate price for a feed enzyme and a cereal. It should provide a useful tool for nutritionists. PMID:11732672

  3. Gastrostomy feeding tube - pump - child

    MedlinePlus

    ... supplies: Feeding pump (electronic or battery powered) Feeding set that matches the feeding pump (includes a feeding ... drip chamber, roller clamp, and long tube) Extension set, for a Bard Button or MIC-KEY (this ...

  4. Alternative feeding strategies and potential disease transmission in Wisconsin white-tailed deer

    USGS Publications Warehouse

    Thompson, A.K.; Samuel, M.D.; VanDeelen, T.R.

    2008-01-01

    We conducted experimental feeding using 3 feeding methods (pile, spread, trough) and 2 quantities (rationed, ad libitum) of shelled corn to compare deer activity and behavior with control sites and evaluate potential direct and indirect transmission of infectious disease in white-tailed deer (Odocoileus virginianus) in central Wisconsin, USA. Deer use was higher at 2 of the feeding sites than at natural feeding areas (P ??? 0.02). Deer spent a higher proportion of time (P < 0.01) feeding at pile (49%) and spread (61%) treatments than at natural feeding areas (36%). We found higher deer use for rationed than ad libitum feeding quantities and feeding intensity was greatest at rationed piles and lowest at ad libitum spreads. We also observed closer pairwise distances (???0.3 m) among deer when corn was provided in a trough relative to spread (P=0.03). Supplemental feeding poses risks for both direct and indirect disease transmission due to higher deer concentration and more intensive use relative to control areas. Concentrated feeding and contact among deer at feeding sites can also increase risk for disease transmission. Our results indicated that restrictions on feeding quantity would not mitigate the potential for disease transmission None of the feeding strategies we evaluated substantially reduced the potential risk for disease transmission and banning supplemental feeding to reduce transmission is warranted.

  5. Innovations Without Added Costs

    ERIC Educational Resources Information Center

    Cereghino, Edward

    1974-01-01

    There is no question that we are in a tight money market, and schools are among the first institutions to feel the squeeze. Therefore, when a plan is offered that provides for innovations without added costs, its something worth noting. (Editor)

  6. What Value "Value Added"?

    ERIC Educational Resources Information Center

    Richards, Andrew

    2015-01-01

    Two quantitative measures of school performance are currently used, the average points score (APS) at Key Stage 2 and value-added (VA), which measures the rate of academic improvement between Key Stage 1 and 2. These figures are used by parents and the Office for Standards in Education to make judgements and comparisons. However, simple…

  7. The ADS All Sky Survey

    NASA Astrophysics Data System (ADS)

    Goodman, Alyssa

    images can be extracted from articles, we will attempt to "astroreference" those images in order allow for their overlay on the sky. "Astroreferencing" is the analog of "georeferencing," where coordinate information is used to overlay information on maps. Our first pass at astroreferencing will be made using the astrometry.net program, in collaboration with one of its creators. If enough optically-visible stars are present in an image, astrometry.net can place it where it goes on the sky. Only a small fraction of ADS holdings contain images solvable by astrometry.net, but for the articles which do, reviving the data in this way holds tremendous value-especially in the case of historically important observations. Lastly, we will also astroreference images by text-mining to extract "metadata" buried in the figure captions and text. As it is built, the ADSASS will effectively create dynamic data layers of astrotags and astroreferenced images. Users will be able to explore these layers using a wide variety of free all-sky data viewers. Our group and our collaborators have been involved in the development of the WorldWide Telescope and Aladin programs, so we will use those to develop examples of how we intend for the ADSASS to be used. But, we plan to ensure that the data feed represented by the ADSASS will be ingestible by any program capable of understanding sky coordinates and all-sky views. Our proposal can only give a glimpse into the wealth of science it will enable, which includes everything from observation-planning to data discovery to studying the sky distributions of classes of objects. Just as it would have been hard to predict the full and amazing impact of GIS and GPS on society, it is similarly hard to gauge the full impact of the NASA ADSASS. The ADS on its own is already the envy of other sciences as a unified research tool, with the advent of the ADSASS, NASA will have led the way to the future once again.

  8. Introducing ADS Labs

    NASA Astrophysics Data System (ADS)

    Accomazzi, Alberto; Henneken, E.; Grant, C. S.; Kurtz, M. J.; Di Milia, G.; Luker, J.; Thompson, D. M.; Bohlen, E.; Murray, S. S.

    2011-05-01

    ADS Labs is a platform that ADS is introducing in order to test and receive feedback from the community on new technologies and prototype services. Currently, ADS Labs features a new interface for abstract searches, faceted filtering of results, visualization of co-authorship networks, article-level recommendations, and a full-text search service. The streamlined abstract search interface provides a simple, one-box search with options for ranking results based on a paper relevancy, freshness, number of citations, and downloads. In addition, it provides advanced rankings based on collaborative filtering techniques. The faceted filtering interface allows users to narrow search results based on a particular property or set of properties ("facets"), allowing users to manage large lists and explore the relationship between them. For any set or sub-set of records, the co-authorship network can be visualized in an interactive way, offering a view of the distribution of contributors and their inter-relationships. This provides an immediate way to detect groups and collaborations involved in a particular research field. For a majority of papers in Astronomy, our new interface will provide a list of related articles of potential interest. The recommendations are based on a number of factors, including text similarity, citations, and co-readership information. The new full-text search interface allows users to find all instances of particular words or phrases in the body of the articles in our full-text archive. This includes all of the scanned literature in ADS as well as a select portion of the current astronomical literature, including ApJ, ApJS, AJ, MNRAS, PASP, A&A, and soon additional content from Springer journals. Fulltext search results include a list of the matching papers as well as a list of "snippets" of text highlighting the context in which the search terms were found. ADS Labs is available at http://adslabs.org

  9. Enhanced mitochondrial complex gene function and reduced liver size may mediate improved feed efficiency of beef cattle during compensatory growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growing ruminants maintained under dietary restriction for extended periods will exhibit compensatory growth when reverted to ad libitum feeding. This period of compensatory growth is associated with increased feed efficiency, lower basal energy requirements, and changes in circulating concentration...

  10. Characterization of laser-induced breakdown spectroscopy (LIBS) for application to space exploration

    SciTech Connect

    Knight, Andrew K.; Scherbarth, Nancy L.; Cremers, David A.; Ferris, Monty J.

    2000-03-01

    Early in the next century, several space missions are planned with the goal of landing craft on asteroids, comets, the Moon, and Mars. To increase the scientific return of these missions, new methods are needed to provide (1) significantly more analyses per mission lifetime, and (2) expanded analytical capabilities. One method that has the potential to meet both of these needs for the elemental analysis of geological samples is laser-induced breakdown spectroscopy (LIBS). These capabilities are possible because the laser plasma provides rapid analysis and the laser pulse can be focused on a remotely located sample to perform a stand-off measurement. Stand-off is defined as a distance up to 20 m between the target and laser. Here we present the results of a characterization of LIBS for the stand-off analysis of soils at reduced air pressures and in a simulated Martian atmosphere (5-7 torr pressure of CO{sub 2}) showing the feasibility of LIBS for space exploration. For example, it is demonstrated that an analytically useful laser plasma can be generated at distances up to 19 m by using only 35 mJ/pulse from a compact laser. Some characteristics of the laser plasma at reduced pressure were also investigated. Temporally and spectrally resolved imaging showed significant changes in the plasma as the pressure was reduced and also showed that the analyte signals and mass ablated from a target were strongly dependent on pressure. As the pressure decreased from 590 torr to the 40-100 torr range, the signals increased by a factor of about 3-4, and as the pressure was further reduced the signals decreased. This behavior can be explained by pressure-dependent changes in the mass of material vaporized and the frequency of collisions between species in the plasma. Changes in the temperature and the electron density of the plasmas with pressure were also examined and detection limits for selected elements were determined. (c) 2000 Society for Applied Spectroscopy.

  11. libCreme: An optimization library for evaluating convex-roof entanglement measures

    NASA Astrophysics Data System (ADS)

    Röthlisberger, Beat; Lehmann, Jörg; Loss, Daniel

    2012-01-01

    We present the software library libCreme which we have previously used to successfully calculate convex-roof entanglement measures of mixed quantum states appearing in realistic physical systems. Evaluating the amount of entanglement in such states is in general a non-trivial task requiring to solve a highly non-linear complex optimization problem. The algorithms provided here are able to achieve to do this for a large and important class of entanglement measures. The library is mostly written in the MATLAB programming language, but is fully compatible to the free and open-source OCTAVE platform. Some inefficient subroutines are written in C/C++ for better performance. This manuscript discusses the most important theoretical concepts and workings of the algorithms, focusing on the actual implementation and usage within the library. Detailed examples in the end should make it easy for the user to apply libCreme to specific problems. Program summaryProgram title:libCreme Catalogue identifier: AEKD_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKD_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU GPL version 3 No. of lines in distributed program, including test data, etc.: 4323 No. of bytes in distributed program, including test data, etc.: 70 542 Distribution format: tar.gz Programming language: Matlab/Octave and C/C++ Computer: All systems running Matlab or Octave Operating system: All systems running Matlab or Octave Classification: 4.9, 4.15 Nature of problem: Evaluate convex-roof entanglement measures. This involves solving a non-linear (unitary) optimization problem. Solution method: Two algorithms are provided: A conjugate-gradient method using a differential-geometric approach and a quasi-Newton method together with a mapping to Euclidean space. Running time: Typically seconds to minutes for a density matrix of a few low-dimensional systems and a decent implementation of the

  12. Effect of creep feed consumption on individual feed intake characteristics and performance of group-housed weanling pigs.

    PubMed

    Bruininx, E M A M; Binnendijk, G P; van der Peet-Schwering, C M C; Schrama, J W; den Hartog, L A; Everts, H; Beynen, A C

    2002-06-01

    To assess the effects of creep feed consumption on individual feed intake characteristics and performance of group-housed weaned pigs, 16 litters (149 piglets) were fed a commercial creep feed (3,040 kcal NE/kg, 15.2 g lysine/kg) supplemented with 1% chromic oxide. Another five litters (48 piglets) were not given access to creep feed (no-feed). Piglets were weaned at 28 d after birth. On d 18, 22, and 27 of age, fecal samples from all the piglets were taken using fecal loops. A green color of the feces indicated that the piglet had eaten creep feed. Piglets that had green-colored feces three times were considered as eaters. Piglets that never showed green-colored feces were considered as non-eaters. At weaning 22 piglets of each type (no-feed, non-eaters, and eaters) were selected based on BW, litter origin, and sex. These 66 pigs were assigned to six pens equipped with computerized feeding stations. Eaters, non-eaters, and no-feed pigs were equally divided over all six pens. After weaning a prestarter (d 0 to 13) and a starter diet (d 14 to 34) were offered for ad libitum consumption. The individual feed intake characteristics of latency time (interval between weaning and first feed intake) and initial feed intake (intake during the first 24 h following first feed intake) and performance traits were determined for all piglets. The pigs that were designated as eaters needed less time between weaning and first feed intake than the pigs that were designated as non-eaters and no-feed pigs (P = 0.04 and P = 0.06, respectively). Initial feed intake was not affected (P > 0.1) by feed intake prior to weaning. However, during d 0 to 8 the eaters had more visits per day during which feed was consumed than both the non-eaters and no-feed pigs. Averaged over the first 8 d after weaning, the ADFI and ADG of the eaters were higher than that of the non-eaters and no-feed pigs (P < 0.05). Averaged over the total 34-d period the effect of creep feed intake on postweaning ADFI was

  13. Psychometric Properties of Scores from the Web-based LibQUAL+ Study of Perceptions of Library Service Quality.

    ERIC Educational Resources Information Center

    Cook, Colleen; Thompson, Bruce

    2001-01-01

    Investigated the psychometric integrity of scores from the LibQUAL+ evaluation of perceived library service quality conducted by ARL (Association of Research Libraries). Examines score structure, score reliability, score correlation and concurrent validity coefficients, scale means, and scale standardized norms, and considers the potential of the…

  14. How Many Dimensions Does It Take To Measure Users' Perceptions of Libraries?: A LibQUAL+Study.

    ERIC Educational Resources Information Center

    Thompson, Bruce; Cook, Colleen; Heath, Fred

    2001-01-01

    Explores the number of dimensions needed to measure users' perceptions of library service quality based on data from the ARL (Association of Research Libraries) LibQUAL+ project. Results were consistent with a view that a single set of scores is one reasonable way to characterize user perceptions of library service quality. (Author/LRW)

  15. Stability of the Reliability of LibQUAL+ (tm) Scores: A Reliability Generalization Meta-Analysis Study.

    ERIC Educational Resources Information Center

    Thompson, Bruce; Cook, Collen

    2002-01-01

    Conducted a reliability generalization meta-analysis of subscale and total scale scores on the Web-administered LibQUAL+ (tm) (Cook and others, 2002), a measure of library service quality. Data for 18,161 participants from 43 universities show that score reliabilities are remarkably invariant across campuses and different over groups. (SLD)

  16. An in situ laser induced breakdown spectroscope (LIBS) for Chandrayaan-2 rover: Ablation kinetics and emissivity estimations

    NASA Astrophysics Data System (ADS)

    Laxmiprasad, A. S.; Sridhar Raja, V. L. N.; Menon, Surya; Goswami, Adwaita; Rao, M. V. H.; Lohar, K. A.

    2013-07-01

    A miniaturized in situ laser induced breakdown spectroscope-LIBS is one of the two lunar rover payloads to be flown in India's next lunar mission Chandrayaan-2, with an objective to carry-out a precise qualitative and quantitative elemental analyses of lunar regolith at the proximity of the landing region. As per the imposed mission constraints and the executed design optimization studies, a compact and light-weight LIBS prototype model is developed at our premises. This paper mainly concerns with the estimation of theoretical aspects; especially on evaluation of elemental ablation parameters and signal-to-noise ratio (SNR) calculations for the designed instrument. Theoretical estimations and simulations yielded an incident laser power density of the order of 5 × 1010 W/cm2 on the target surface at a defined lens-to-surface distance (LTSD) of 200 mm and revealed an SNR > 100 for most of the elements under consideration. This paper also addresses the impact of LTSD variation on detection capability. The estimation of plasma-temperatures was carried out utilizing the emission spectra obtained under high vacuum environments employing the LIBS laboratory model. Experimental investigations and the performed theoretical estimations asserted the successful operation of the configured LIBS instrument for in situ elemental analyses on lunar surface.

  17. Evaluation of laser-induced breakdown spectroscopy (LIBS) for measurement of silica on filter samples of coal dust.

    PubMed

    Stipe, Christopher B; Miller, Arthur L; Brown, Jonathan; Guevara, Edward; Cauda, Emanuele

    2012-11-01

    Airborne silica dust (quartz) is common in coal mines and represents a respiratory hazard that can lead to silicosis, a potentially fatal lung disease. With an eye toward developing a portable monitoring device for rapid analysis of silica dust, laser-induced breakdown spectroscopy (LIBS) was used to quantify quartz in coal dust samples collected on filter media. Pure silica (Min-U-Sil™ 5), Georgia kaolin, and Pittsburgh-4 and Illinois-6 coal dusts were deposited separately and at multiple mass loadings onto 37-mm polyvinylchloride (PVC) filters. LIBS-generated silicon emission was monitored at 288.16 nm, and non-silica contributions to that signal from kaolinite were removed by simultaneously detecting aluminum. Measurements of the four samples were used to calculate limits of detection (LOD) for silicon and aluminum of approximately 0.08 μg/cm(2) and 0.05 μg/cm(2), respectively (corresponding to 0.16 μg/cm(2) and 0.20 μg/cm(2) for silica and kaolinite, respectively). Relative errors of prediction are around 10%. Results demonstrate that LIBS can dependably quantify silica on filter samples of coal dust and confirm that accurate quantification can be achieved for very lightly loaded samples, which supports the potential application of LIBS for rapid, in-field monitoring. PMID:23146184

  18. "We Thought It Might Encourage Participation." Using Lottery Incentives to Improve LibQUAL+[TM] Response Rates among Students

    ERIC Educational Resources Information Center

    Buck, Stefanie; Nutefall, Jennifer E.; Bridges, Laurie M.

    2012-01-01

    Libraries deploying the LibQUAL+[TM] survey can offer a lottery incentive and many do so in the hope of increasing response rates. Other libraries may be prohibited from offering one because of Institutional Review Board restrictions, as is the case at Oregon State University. We wanted to discover why libraries offer lottery incentives, what…

  19. Improving Library Service Quality to Graduate Students: LibQual+[TM] Survey Results in a Practical Setting

    ERIC Educational Resources Information Center

    Jankowska, Maria Anna; Hertel, Karen; Young, Nancy J.

    2006-01-01

    The LibQUAL+[TM] survey was conducted to determine user satisfaction and expectations concerning library service quality. The results of the "22 items and a box" constituted a rich source of information for the University of Idaho (UI) Library's strategic planning process. Focusing on graduate students, this study used three methodologies to…

  20. Disintermediation in the Year 2010: Using Scenarios To Identify Key Issues and Relevance of IMPEL2 eLib Project.

    ERIC Educational Resources Information Center

    Edwards, Catherine; Day, Joan; Walton, Graham

    Among information workers, the term "disintermediation" has been used to describe the diminishing role of the intermediary associated with the electronic information environment. IMPEL2 is a JISC-funded e-Lib Project investigating the social, organizational, and cultural impacts of the growing electronic library in United Kingdom higher education.…

  1. Crystal structure and photoluminescence properties of Eu 2+-activated Ba 2LiB 5O 10 phosphors

    NASA Astrophysics Data System (ADS)

    Wang, Qian; Deng, Degang; Xu, Shiqing; Hua, Youjie; Huang, Lihui; Wang, Huanping; Zhao, Shilong; Jia, Guohua; Li, Chenxia

    2011-10-01

    A novel orange-yellow-emitting Ba 2LiB 5O 10:Eu 2+ phosphor has been synthesized by traditional high temperature solid state reaction. A monoclinic crystal structure of Barium lithiumborates Ba 2LiB 5O 10 was verified by the investigation of X-ray diffraction (XRD). The compound crystallizes in the space group of P121/m1(11) (Z = 2) with the unit cell parameters a = 4.414(1) Å, b = 14.576(2) Å, c = 6.697(2) Å and β = 104.26(2)°. Barium and lithium atoms are located in distorted octahedral and tetrahedral oxygen coordinations, respectively. Upon around 365 nm excitation, the Eu 2+-activated Ba 2LiB 5O 10 phosphors exhibit a single broad emission band with the maximum at about 587 nm, due to the 4f 65d → 4f 7(8S 7/2) transition of Eu 2+. This work investigates the relationship between luminescence properties and structural characterization of the Ba 2LiB 5O 10: Eu 2+. This newly developed phosphor shows high potential as a phosphor conversion for white LED applications.

  2. Evaluation of Laser-Induced Breakdown Spectroscopy (LIBS) for Measurement of Silica on Filter Samples of Coal Dust

    PubMed Central

    Stipe, Christopher B.; Miller, Arthur L.; Brown, Jonathan; Guevara, Edward; Cauda, Emanuele

    2015-01-01

    Airborne silica dust (quartz) is common in coal mines and represents a respiratory hazard that can lead to silicosis, a potentially fatal lung disease. With an eye toward developing a portable monitoring device for rapid analysis of silica dust, laser-induced breakdown spectroscopy (LIBS) was used to quantify quartz in coal dust samples collected on filter media. Pure silica (Min-U-Sil™ 5), Georgia kaolin, and Pittsburgh-4 and Illinois-6 coal dusts were deposited separately and at multiple mass loadings onto 37-mm polyvinylchloride (PVC) filters. LIBS-generated silicon emission was monitored at 288.16 nm, and non-silica contributions to that signal from kaolinite were removed by simultaneously detecting aluminum. Measurements of the four samples were used to calculate limits of detection (LOD) for silicon and aluminum of approximately 0.08 µg/cm2 and 0.05 µg/cm2, respectively (corresponding to 0.16 µg/cm2 and 0.20 µg/cm2 for silica and kaolinite, respectively). Relative errors of prediction are around 10%. Results demonstrate that LIBS can dependably quantify silica on filter samples of coal dust and confirm that accurate quantification can be achieved for very lightly loaded samples, which supports the potential application of LIBS for rapid, in-field monitoring. PMID:23146184

  3. Remote quantitative analysis of minerals based on multispectral line-calibrated laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Wan, Xiong; Wang, Peng

    2014-01-01

    Laser-induced breakdown spectroscopy (LIBS) is a feasible remote sensing technique used for mineral analysis in some unapproachable places where in situ probing is needed, such as analysis of radioactive elements in a nuclear leak or the detection of elemental compositions and contents of minerals on planetary and lunar surfaces. Here a compact custom 15 m focus optical component, combining a six times beam expander with a telescope, has been built, with which the laser beam of a 1064 nm Nd ; YAG laser is focused on remote minerals. The excited LIBS signals that reveal the elemental compositions of minerals are collected by another compact single lens-based signal acquisition system. In our remote LIBS investigations, the LIBS spectra of an unknown ore have been detected, from which the metal compositions are obtained. In addition, a multi-spectral line calibration (MSLC) method is proposed for the quantitative analysis of elements. The feasibility of the MSLC and its superiority over a single-wavelength determination have been confirmed by comparison with traditional chemical analysis of the copper content in the ore. PMID:25239065

  4. GammaLib and ctools. A software framework for the analysis of astronomical gamma-ray data

    NASA Astrophysics Data System (ADS)

    Knödlseder, J.; Mayer, M.; Deil, C.; Cayrou, J.-B.; Owen, E.; Kelley-Hoskins, N.; Lu, C.-C.; Buehler, R.; Forest, F.; Louge, T.; Siejkowski, H.; Kosack, K.; Gerard, L.; Schulz, A.; Martin, P.; Sanchez, D.; Ohm, S.; Hassan, T.; Brau-Nogué, S.

    2016-08-01

    The field of gamma-ray astronomy has seen important progress during the last decade, yet to date no common software framework has been developed for the scientific analysis of gamma-ray telescope data. We propose to fill this gap by means of the GammaLib software, a generic library that we have developed to support the analysis of gamma-ray event data. GammaLib was written in C++ and all functionality is available in Python through an extension module. Based on this framework we have developed the ctools software package, a suite of software tools that enables flexible workflows to be built for the analysis of Imaging Air Cherenkov Telescope event data. The ctools are inspired by science analysis software available for existing high-energy astronomy instruments, and they follow the modular ftools model developed by the High Energy Astrophysics Science Archive Research Center. The ctools were written in Python and C++, and can be either used from the command line via shell scripts or directly from Python. In this paper we present the GammaLib and ctools software versions 1.0 that were released at the end of 2015. GammaLib and ctools are ready for the science analysis of Imaging Air Cherenkov Telescope event data, and also support the analysis of Fermi-LAT data and the exploitation of the COMPTEL legacy data archive. We propose using ctools as the science tools software for the Cherenkov Telescope Array Observatory.

  5. Partial Least Squares and Neural Networks for Quantitative Calibration of Laser-induced Breakdown Spectroscopy (LIBs) of Geologic Samples

    NASA Technical Reports Server (NTRS)

    Anderson, R. B.; Morris, Richard V.; Clegg, S. M.; Humphries, S. D.; Wiens, R. C.; Bell, J. F., III; Mertzman, S. A.

    2010-01-01

    The ChemCam instrument [1] on the Mars Science Laboratory (MSL) rover will be used to obtain the chemical composition of surface targets within 7 m of the rover using Laser Induced Breakdown Spectroscopy (LIBS). ChemCam analyzes atomic emission spectra (240-800 nm) from a plasma created by a pulsed Nd:KGW 1067 nm laser. The LIBS spectra can be used in a semiquantitative way to rapidly classify targets (e.g., basalt, andesite, carbonate, sulfate, etc.) and in a quantitative way to estimate their major and minor element chemical compositions. Quantitative chemical analysis from LIBS spectra is complicated by a number of factors, including chemical matrix effects [2]. Recent work has shown promising results using multivariate techniques such as partial least squares (PLS) regression and artificial neural networks (ANN) to predict elemental abundances in samples [e.g. 2-6]. To develop, refine, and evaluate analysis schemes for LIBS spectra of geologic materials, we collected spectra of a diverse set of well-characterized natural geologic samples and are comparing the predictive abilities of PLS, cascade correlation ANN (CC-ANN) and multilayer perceptron ANN (MLP-ANN) analysis procedures.

  6. Laser-induced breakdown spectroscopy (LIBS) to measure quantitatively soil carbon with emphasis on soil organic carbon. A review.

    PubMed

    Senesi, Giorgio S; Senesi, Nicola

    2016-09-28

    Soil organic carbon (OC) measurement is a crucial factor for quantifying soil C pools and inventories and monitoring the inherent temporal and spatial heterogeneity and changes of soil OC content. These are relevant issues in addressing sustainable management of terrestrial OC aiming to enhance C sequestration in soil, thus mitigating the impact of increasing CO2 concentration in the atmosphere and related effects on global climate change. Nowadays, dry combustion by an elemental analyzer or wet combustion by dichromate oxidation of the soil sample are the most recommended and commonly used methods for quantitative soil OC determination. However, the unanimously recognized uncertainties and limitations of these classical laboursome methods have prompted research efforts focusing on the development and application of more advanced and appealing techniques and methods for the measurement of soil OC in the laboratory and possibly in situ in the field. Among these laser-induced breakdown spectroscopy (LIBS) has raised the highest interest for its unique advantages. After an introduction and a highlight of the LIBS basic principles, instrumentation, methodologies and supporting chemometric methods, the main body of this review provides an historical and critical overview of the developments and results obtained up-to-now by the application of LIBS to the quantitative measurement of soil C and especially OC content. A brief critical summary of LIBS advantages and limitations/drawbacks including some final remarks and future perspectives concludes this review. PMID:27619082

  7. The effects of laser repetition rate on femtosecond laser ablation of dry bone: a thermal and LIBS study.

    PubMed

    Gill, Ruby K; Smith, Zachary J; Lee, Changwon; Wachsmann-Hogiu, Sebastian

    2016-01-01

    The aim of this study is to understand the effect of varying laser repetition rate on thermal energy accumulation and dissipation as well as femtosecond Laser Induced Breakdown Spectroscopy (fsLIBS) signals, which may help create the framework for clinical translation of femtosecond lasers for surgical procedures. We study the effect of repetition rates on ablation widths, sample temperature, and LIBS signal of bone. SEM images were acquired to quantify the morphology of the ablated volume and fsLIBS was performed to characterize changes in signal intensity and background. We also report for the first time experimentally measured temperature distributions of bone irradiated with femtosecond lasers at repetition rates below and above carbonization conditions. While high repetition rates would allow for faster cutting, heat accumulation exceeds heat dissipation and results in carbonization of the sample. At repetition rates where carbonization occurs, the sample temperature increases to a level that is well above the threshold for irreversible cellular damage. These results highlight the importance of the need for careful selection of the repetition rate for a femtosecond laser surgery procedure to minimize the extent of thermal damage to surrounding tissues and prevent misclassification of tissue by fsLIBS analysis. PMID:26260774

  8. A Simple Laser Induced Breakdown Spectroscopy (LIBS) System for Use at Multiple Levels in the Undergraduate Chemistry Curriculum

    ERIC Educational Resources Information Center

    Randall, David W.; Hayes, Ryan T.; Wong, Peter A.

    2013-01-01

    A LIBS (laser induced breakdown spectroscopy) spectrometer constructed by the instructor is reported for use in undergraduate analytical chemistry experiments. The modular spectrometer described here is based on commonly available components including a commercial Nd:YAG laser and a compact UV-vis spectrometer. The modular approach provides a…

  9. Mixed feed evaporator

    DOEpatents

    Vakil, Himanshu B.; Kosky, Philip G.

    1982-01-01

    In the preparation of the gaseous reactant feed to undergo a chemical reaction requiring the presence of steam, the efficiency of overall power utilization is improved by premixing the gaseous reactant feed with water and then heating to evaporate the water in the presence of the gaseous reactant feed, the heating fluid utilized being at a temperature below the boiling point of water at the pressure in the volume where the evaporation occurs.

  10. Modification of polyurethane to reduce occlusion of enteral feeding tubes

    SciTech Connect

    Gaither, Kari A.; Tarasevich, Barbara J.; Goheen, Steven C.

    2009-04-27

    Feeding tubes are used to supply nutritional formula to immobilized patients. The most common cause for failure of enteral feeding tubes is their occlusion. The purpose of this study was to examine whether occlusion of enteral feeding tubes could be minimized using an additive. An open, intermittent enteral feeding system was simulated in the laboratory and data was collected over a period ranging from 2 to 6 days. Feeding formula was cycled through a feeding tube in either the presence or absence of simulated gastric acid in an effort to generate a reproducible occlusion. Pressures in the tube were measured frequently throughout these cycles. We observed pressure spikes with each cycle, but never a complete occlusion. Pressure spikes formed only when simulated gastric acid was mixed with the feeding solution. Large amounts of feeding formula adsorbed onto polyurethane surfaces in the presence of gastric acid. The maximum pressure was reduced by about half from 2.0 psi to 0.8 psi when polyvinyl alcohol (PVA) was added. The addition of PVA to polyurethane also reduced the contact angle from 83° (untreated) to approximately 64° in the presence of PVA. Furthermore, when formula was added to polyurethane in the presence of PVA the thickness of the layer that remained on the surface was almost 10 times greater in controls than on PVA-treated surfaces. These results suggest that a treatment that increases the hydrophilicity of the feeding tube may help minimize clogging.

  11. Infectious waste feed system

    DOEpatents

    Coulthard, E. James

    1994-01-01

    An infectious waste feed system for comminuting infectious waste and feeding the comminuted waste to a combustor automatically without the need for human intervention. The system includes a receptacle for accepting waste materials. Preferably, the receptacle includes a first and second compartment and a means for sealing the first and second compartments from the atmosphere. A shredder is disposed to comminute waste materials accepted in the receptacle to a predetermined size. A trough is disposed to receive the comminuted waste materials from the shredder. A feeding means is disposed within the trough and is movable in a first and second direction for feeding the comminuted waste materials to a combustor.

  12. VLBI2010 Feed Comparison

    NASA Technical Reports Server (NTRS)

    Petrachenko, Bill

    2013-01-01

    VLBI2010 requires a feed that simultaneously has high efficiency over the full 2.2-14 GHz frequency range. The simultaneity requirement implies that the feed must operate at high efficiency over the full frequency range without the need to adjust its focal position to account for frequency dependent phase centre variations. Two feeds meet this specification: The Eleven Feed developed at Chalmers University. (For more information, contact Miroslav Pantaleev, miroslav.pantaleev@chalmers.se. The Eleven Feed, integrated with LNA's in a cryogenic receiver, is available as a product from Omnisys Instruments, info@omnisys.se). The Quadruple Ridged Flared Horn (QRFH) developed at the California Institute of Technology. (For more information please contact Ahmed Akgiray, aakgiray@ieee.org or Sander Weinreb, sweinreb@caltech.edu) Although not VLBI2010 compliant, two triband S/X/Ka feeds are also being developed for the commissioning of VLBI2010 antennas, for S/X observations during the VLBI2010 transition period, and to support X/Ka CRF observations. The two feeds are: The Twin Telescopes Wettzell (TTW) triband feed developed by Mirad Microwave. (For more information please contact Gerhard Kronschnabl, Gerhard.Kronschnabl@bkg.bund.de) The RAEGE (Spain) triband feed developed at Yebes Observatory. (For more information please contact Jose Antonio Lopez Perez, ja.lopezperez@oan.es)

  13. 21 CFR 509.6 - Added poisonous or deleterious substances.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Added poisonous or deleterious substances. 509.6 Section 509.6 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS UNAVOIDABLE CONTAMINANTS IN ANIMAL FOOD AND...

  14. Two Virasoro symmetries in stringy warped AdS3

    NASA Astrophysics Data System (ADS)

    Compère, Geoffrey; Guica, Monica; Rodriguez, Maria J.

    2014-12-01

    We study three-dimensional consistent truncations of type IIB supergravity which admit warped AdS3 solutions. These theories contain subsectors that have no bulk dynamics. We show that the symplectic form for these theories, when restricted to the non-dynamical subsectors, equals the symplectic form for pure Einstein gravity in AdS3. Consequently, for each consistent choice of boundary conditions in AdS3, we can define a consistent phase space in warped AdS3 with identical conserved charges. This way, we easily obtain a Virasoro × Virasoro asymptotic symmetry algebra in warped AdS3; two different types of Virasoro × Kač-Moody symmetries are also consistent alternatives.

  15. Growth and morphology of large LiB 3 O 5 single crystals

    NASA Astrophysics Data System (ADS)

    Nikolov, I.; Perlov, D.; Livneh, S.; Sanchez, E.; Czechowicz, P.; Kondilenko, V.; Loiacono, D.

    2011-09-01

    LiB 3O 5 (LBO) is one of the most widely used nonlinear optical crystals, therefore the growth of large high quality boules is of major significance to the photonics industry. In the past, LBO single crystals were limited in both size and quality, the latter of which was primarily due to the presence of bubbles, flux inclusions and striations. Furthermore, commercially available material exhibited variable optical absorption. In this research we have perfected the Top-Seeded Solution Growth (TSSG) technique for the growth of LBO single crystals from MoO 3-based fluxes. This particular growth process was developed through a thorough study of melt dynamics. Based on the results observed in our modeling experiments, the major growth parameters were optimized. The crystal morphology was modified in order to increase the material yield and eliminate inclusions. As a result we have achieved LBO single crystals of both size and quality, which we believe to be market leading.

  16. Nucleation, growth and characterization of LiB 3O 5 single crystals

    NASA Astrophysics Data System (ADS)

    Kannan, C. V.; Kimura, H.; Miyazaki, A.; Ramasamy, P.

    2005-02-01

    Nucleation parameters of LiB 3O 5 (LBO) that crystallized from high-temperature solution using two different solvents, namely boron oxide (B 2O 3) and molybdate (MoO 3), have been studied for better understanding of the growth process. Our results showed that B 2O 3 solvent yielded a larger value of metastable zone width than that of molybdate flux, thus giving more stability to the solution. Based on our theoretical considerations, inclusion-free LBO crystals have been grown by spontaneous nucleation and TSSG techniques using B 2O 3 solvent. Variation of optical absorption coefficient and refractive indices with wavelength has been studied. Results of optical and mechanical properties showed that the grown crystals are highly transparent and possesses hardness higher than that of KTP crystal.

  17. LibCPIXE: A PIXE simulation open-source library for multilayered samples

    NASA Astrophysics Data System (ADS)

    Pascual-Izarra, C.; Barradas, N. P.; Reis, M. A.

    2006-08-01

    Most particle induced X-ray emission (PIXE) data analysis codes are not focused on handling multilayered samples. We have developed an open-source library called "LibCPIXE", for PIXE data analysis. It is written in standard C and implements functions for simulating X-ray yields of PIXE spectra taken from arbitrary samples, including multilayered targets. The library is designed to be fast, portable, modular and scalable, as well as to facilitate its incorporation into any existing program. In order to demonstrate the capabilities of the library, a program called CPIXE was developed and used to analyze various real samples involving both bulk and layered samples. Just as the library, the CPIXE source code is freely available under the General Public License. We demonstrate that it runs both under GNU/Linux systems as well as under MS Windows. There is in principle no limitation to port it to other platforms.

  18. LIBS Detection of Heavy Metal Elements in Liquid Solutions by Using Wood Pellet as Sample Matrix

    NASA Astrophysics Data System (ADS)

    Wen, Guanhong; Sun, Duixiong; Su, Maogen; Dong, Chenzhong

    2014-06-01

    Laser-induced breakdown spectroscopy (LIBS) has been applied to the analysis of heavy metals in liquid samples. A new approach was presented to lower the limit of detection (LOD) and minimize the sample matrix effects, in which dried wood pellets absorbed the given amounts of Cr standard solutions and then were baked because they have stronger and rapid absorption properties for liquid samples as well as simple elemental compositions. In this work, we have taken a typical heavy metal Cr element as an example, and investigated the spectral feasibility of Cr solutions and dried wood pellets before and after absorbing Cr solutions at the same experimental conditions. The results were demonstrated to successfully produce a superior analytical response for heavy metal elements by using wood pellet as sample matrix according to the obtained LOD of 0.07 ppm for Cr element in solutions.

  19. Remote Raman - Laser Induced Breakdown Spectroscopy (LIBS) Geochemical Investigation under Venus Atmospheric Conditions

    NASA Astrophysics Data System (ADS)

    Clegg, S. M.; Barefield, J. E.; Humphries, S.; Wiens, R. C.; Vaniman, D. T.; Sharma, S. K.; Misra, A. K.; Dyar, M. D.; Smrekar, S. E.

    2010-12-01

    The extreme Venus surface temperatures (~740 K) and atmospheric pressures (~93 atm) create a challenging environment for surface missions. Scientific investigations capable of Venus geochemical observations must be completed within hours of landing before the lander will be overcome by the harsh atmosphere. A combined remote Raman - LIBS (Laser Induced Breakdown Spectroscopy) instrument is capable of accomplishing the geochemical science goals without the risks associated with collecting samples and bringing them into the lander. Wiens et al. [1] and Sharma et al. [2] demonstrated that both analytical techniques can be integrated into a single instrument capable of planetary missions. The focus of this paper is to explore the capability to probe geologic samples with Raman - LIBS and demonstrate quantitative analysis under Venus surface conditions. Raman and LIBS are highly complementary analytical techniques capable of detecting both the mineralogical and geochemical composition of Venus surface materials. These techniques have the potential to profoundly increase our knowledge of the Venus surface composition, which is currently limited to geochemical data from Soviet Venera and VEGA landers that collectively suggest a surface composition that is primarily tholeiitic basaltic [3] with some potentially more evolved compositions and, in some locations, K-rich trachyandesite. These landers were not equipped to probe the surface mineralogy as can be accomplished with Raman spectroscopy. Based on the observed compositional differences and recognizing the imprecise nature of the existing data, 15 samples were chosen to constitute a Venus-analog suite for this study, including five basalts, two each of andesites, dacites, and sulfates, and single samples of a foidite, trachy-andesite, rhyolite, and basaltic trachyandesite under Venus conditions. LIBS data reduction involved generating a partial least squares (PLS) model with a subset of the rock powder standards to

  20. Growth and nonlinear optical properties of Zn-doped LiB3O5 crystals

    NASA Astrophysics Data System (ADS)

    Yang, Lei; Yue, Yinchao; Mao, Qian; Li, Xiaomao; Hu, Zhanggui

    2015-05-01

    Zn-doped LiB3O5 (LBO) single crystals with high quality were successfully grown from the Li2O-MoO3-ZnF2 ternary system by the top-seeded solution growth method. The suitable region for LBO crystal growth was investigated by growth experiments, as well as viscosity and volatility measurements, which confirmed that the optimal molar ratio of Li2O:MoO3:ZnF2 was 1:1.5:0.2. The second-harmonic generation efficiency of Zn-doped LBO crystal increased by 16% compared with that of the LBO crystals grown from the MoO3 flux. The optical homogeneity was at 10-6 cm-1. Optical absorption at the critical wavelengths of 1064 nm was measured to be 15 and 18 ppm cm-1, respectively.

  1. Li/B ratio in deep fluids an indicator of their generation depth

    NASA Astrophysics Data System (ADS)

    Hirajima, Takao; Sengen, Yoshiteru; Nishimura, Koshi; Ohsawa, Shinji

    2010-05-01

    that the fluid inclusions in the studied specimens were produced during multi-stages, probably higher salinity syn-metamorphic ones and lower salinity post-peak metamorphic ones. The deep fluids contained in the quartz veins/lenses were leached into the extra-pure water by the crush leaching technique, mainly following Banks and Yardley (1992) and Bottrell et al. (1988). Composition in the leached fluids was analyzed using gas-chromatography and ICP-MS. All extracted fluids are characterized by significantly lower Cl/(Lix2000+Bx500+Cl) (<0.2) ratio than the value of the modern sea water (ca. 0.8). Li(x2000)/B(x500) ratio of extracted fluids varies from 0.1 to 1.0 and shows a positive correlation with the metamorphic grade of the host rock., i.e., ca. 0.1 in the chlorite zone, ca. 0.2 in the garnet zone, ca. 0.4 in the biotite zone and 0.4-1.0 in the eclogite unit. Literature data of Li-B contents in natural HP metamorphic rocks suggest that Li/B ration of dehydrated fluid released from subducted meta-basalts increases with the metamorphic depth (Marschall et al., 2006; 2007). These evidences suggest that Li/B ratio of deep fluids has a potential evaluating the generated depth, although there remains several factors which control should Li/B ration ratio in the fluid should be clarified.

  2. Ultrafast Laser-Based Spectroscopy and Sensing: Applications in LIBS, CARS, and THz Spectroscopy

    PubMed Central

    Leahy-Hoppa, Megan R.; Miragliotta, Joseph; Osiander, Robert; Burnett, Jennifer; Dikmelik, Yamac; McEnnis, Caroline; Spicer, James B.

    2010-01-01

    Ultrafast pulsed lasers find application in a range of spectroscopy and sensing techniques including laser induced breakdown spectroscopy (LIBS), coherent Raman spectroscopy, and terahertz (THz) spectroscopy. Whether based on absorption or emission processes, the characteristics of these techniques are heavily influenced by the use of ultrafast pulses in the signal generation process. Depending on the energy of the pulses used, the essential laser interaction process can primarily involve lattice vibrations, molecular rotations, or a combination of excited states produced by laser heating. While some of these techniques are currently confined to sensing at close ranges, others can be implemented for remote spectroscopic sensing owing principally to the laser pulse duration. We present a review of ultrafast laser-based spectroscopy techniques and discuss the use of these techniques to current and potential chemical and environmental sensing applications. PMID:22399883

  3. Potential application of LIBS to NNSA next generation safeguards initiative (NGSI)

    SciTech Connect

    Barefield Ii, James E; Clegg, Samuel M; Veirs, Douglas K; Browne, Mike; Lopez, Leon; Martinez, Ron; Le, Loan; Lamontagne, Stephen A

    2009-01-01

    In a climate in which states and nations have been and perhaps currently are involved in the prol iferation of nuclear materials and technologies, advanced methodologies and improvements in current measurement techniques are needed to combat new threats and increased levels of sophistication. The Department of Energy through the National Nuclear Security Administration (NNSA) has undertaken a broad review of International Safeguards. The conclusion from that review was that a comprehensive initiative to revitalize international safeguards technology and the human resource base was urgently needed to keep pace with demands and increasingly sophisticated emerging safeguards challenges. To address these challenges, NNSA launched the Next Generation Safeguards Initiative (NGSI) to develop policies, concepts, technologies, expertise, and infrastructure necessary to sustain the international safeguards system as its mission evolves for the next 25 years. NGSI is designed to revitalize and strengthen the U.S. safeguards technical base, recognizing that without a robust program the United States of America will not be in a position to exercise leadership or provide the necessary support to the IAEA (International Atomic Energy Agency). International safeguards as administrated by the IAEA are the primary vehicle for verifying compliance with the peaceful use and nonproliferation of nuclear materials and technologies. Laser Induced Breakdown Spectroscopy or LIBS has the potential to support the goals of NGSI as follows: by providing (1) automated analysis in complex nuclear processing or reprocessing facilities in real-time or near real-time without sample preparation or removal, (2) isotopic and important elemental ratio (Cm/Pu, Cm/U, ... etc) analysis, and (3) centralized remote control, process monitoring, and analysis of nuclear materials in nuclear facilities at multiple locations within the facility. Potential application of LIBS to international safeguards as

  4. LIBSLog: Laser Induced Breakdown Spectroscopy (LIBS) based logging tool for exploration of boreholes

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Chu, P.

    2012-12-01

    We present a novel downhole instrument, currently under development at Honeybee Robotics with SBIR funding from NASA. The device is designed to characterize elemental composition as a function of depth in terrestrial and non-terrestrial geological formations. The instrument consists of a miniaturized LIBS analyzer integrated in a 2" diameter drill string. While the drill provides subsurface access, the LIBS analyzer provides information on the elemental composition of the borehole wall. This instrument has a variety of space applications ranging from exploration of the Moon for which it was originally designed, to Mars and Europa. The system can also be deployed in a wireline configuration as a logging probe, called LIBSLog. The LIBSLog could be lowered into existing boreholes and scan the borehole wall with depth. Subsurface analysis is usually performed by sample acquisition through a drill or excavator, followed by sample preparation and subsequent sample presentation to an instrument or suite of instruments. An alternative approach consisting in bringing a miniaturized version of the instrument to the sample has many advantages over the traditional methodology, as it allows faster response, reduced probability of cross-contamination and a simplification in the sampling mechanisms. The results for lunar simulant NU-LHT-2M show a value for the concentration of iron ranging between 2.29% and 3.05% depending on the atomic line selected. The accepted value for the sample analyzed is 2.83%, showing the capability for the system in development to provide qualitative and semi-quantitative analysis in real-time.

  5. Double laser LIBS and micro-XRF spectroscopy applied to characterize materials coming from the Greek-Roman theater of Taormina

    NASA Astrophysics Data System (ADS)

    Alberghina, Maria Francesca; Barraco, Rosita; Brai, Maria; Schillaci, Tiziano; Tranchina, Luigi

    2009-07-01

    The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown, in recent years, its great potential for rapid qualitative analysis of materials. The possibility to implement a portable instrument that perform LIBS analysis makes this technique particularly useful for in situ analysis in the field of cultural heritages. The aim of this work is to compare the results, obtained by LIBS measurements with X-Ray Fluorescence (XRF) ones, on calcareous and refractory materials coming from the Greek-Roman theater of Taormina. Calibration curves for LIBS and XRF were obtained by measuring certified reference materials and using them as standards. LIBS measurements were performed with a new mobile instrument Modı (Mobile Double pulse Instrument for LIBS Analysis) that use an innovative experimental set-up, based on the use of two suitably retarded laser pulses that greatly improves the potential of this technique for accurate quantitative analysis. XRF analyses were performed with a portable instrument ArtTAX that use a collimated X-Ray beam equipped with a fluxing system of helium gas on the detection path to the aim to detect the lighter elements with a good accuracy. LIBS results have shown that this technique is highly subjected to the sample chemical and physical characteristics.

  6. Feed up, Feedback, and Feed Forward

    ERIC Educational Resources Information Center

    Fisher, Douglas; Frey, Nancy

    2011-01-01

    "Feeding up" establishes a substantive line of inquiry that compels learners to engage in investigation and inquire. It also forms the basis for the assessments that follow. Once students understand the purpose and begin to work, they receive "feedback" that is timely and scaffolds their understanding. Based on their responses, the teacher gains a…

  7. Leading Change, Adding Value.

    PubMed

    Evans, Nick

    2016-09-12

    Essential facts Leading Change, Adding Value is NHS England's new nursing and midwifery framework. It is designed to build on Compassion in Practice (CiP), which was published 3 years ago and set out the 6Cs: compassion, care, commitment, courage, competence and communication. CiP established the values at the heart of nursing and midwifery, while the new framework sets out how staff can help transform the health and care sectors to meet the aims of the NHS England's Five Year Forward View. PMID:27615573

  8. By-Product Feeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    By-product feeds are generated from the production of food, fiber, and bio-energy products for human consumption. They include plant feedstuffs such as hulls, stalks, peels, and oil seed meals, and animal by-products such as blood meal, fats, bone meal, or processed organ meats. Some feed by-product...

  9. Infant Feeding and Attachment.

    ERIC Educational Resources Information Center

    Ainsworth, Mary D. Salter; Tracy, Russel L.

    This paper has two major purposes: first, to consider how infant feeding behavior may fit into attachment theory; and second, to cite some evidence to show how an infant's early interaction with his mother in the feeding situation is related to subsequent development. It was found that sucking and rooting are precursor attachment behaviors that…

  10. Tube Feeding Transition Plateaus

    ERIC Educational Resources Information Center

    Klein, Marsha Dunn

    2007-01-01

    The journey children make from tube feeding to oral feeding is personal for each child and family. There is a sequence of predictable plateaus that children climb as they move toward orally eating. By better understanding this sequence, parents and children can maximize the development, learning, enjoyment and confidence at each plateau. The…

  11. Development of Wideband Feed

    NASA Astrophysics Data System (ADS)

    Ujihara, Hideki; Takefuji, Kazuhiro; Sekido, Mamoru; Kondo, Tetsuro

    2015-08-01

    Wideband feeds have developed for Kashima 34m antenna and new 2.4m portable VLBI antennas. Prototypes of the wideband feeds are multimode horns, first one was set on 34m in the end of 2013, and then replaced next one with 6.5-15.0GHz receiving frequency. Now, a new feed for 3.2GHz-14.4GHz will be installed in 2.4m and 34m antennas in this spring, which are named NINJA feed, because of its design flexibility in beam shpae. Next, IGUANA feed is now under design and fabrication, which is aimed for 2.2-22GHz and covers VGOS(VLBI2010) specification. This has coaxial structure, the smaller "daughter feed" for 6.4-22GHz is placed in the center of the larger "Mother feed" for 2.2-6.4GHz.They are used for our project of time and frequency transfer between remote atomic clocks by wideband VLBI, named Gala-V(Garapagos VLBI), and will also be used wideband VLBI observation for astronmy and geodesy.Prototype feeds were tested in measurement of aperture efficiency, SEFD and Tsys of 34m "Super Kashima Antenna" and both 6.7/12.2GHz methanol maser detection in one reciever system, and then better one is used for wideband VLBI observations.

  12. Testing Feeds for Salmonella.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Human salmonellosis outbreaks have been linked to contamination of animal feeds. Thus it is crucial to employ sensitive Salmonella detection methods for animal feeds. Based on a review of the literature, Salmonella sustains acid injury at about pH 4.0 to5.0. Low pH can also alter the metabolism of S...

  13. Enhanced temperature and emission from a standoff 266 nm laser initiated LIBS plasma using a simultaneous 10.6 microm CO2 laser pulse.

    PubMed

    Pal, Avishekh; Waterbury, Robert D; Dottery, Edwin L; Killinger, Dennis K

    2009-05-25

    A deep UV 266 nm laser induced LIBS plasma has been enhanced by using a simultaneous 10.6 microm CO(2) laser pulse at standoff ranges up to 55 m for several targets including metals, ceramics and plastics. The LIBS plasma emission was produced, for the first time, by a 266 nm laser and was enhanced by several orders of magnitude using the CO(2) laser pulse. The temperature of the enhanced LIBS plasma was measured, for the first time, and was observed to increase by about 3000K due to the addition of the CO(2) laser pulse. PMID:19466135

  14. Dirac operator on fuzzy AdS2

    NASA Astrophysics Data System (ADS)

    Fakhri, Hossein; Imaanpur, Ali

    2003-03-01

    In this article we construct the chirality and Dirac operators on noncommutative AdS2. We also derive the discrete spectrum of the Dirac operator which is important in the study of the spectral triple associated to AdS2. It is shown that the degeneracy of the spectrum present in the commutative AdS2 is lifted in the noncommutative case. The way we construct the chirality operator is suggestive of how to introduce the projector operators of the corresponding projective modules on this space.

  15. An xp model on AdS2 spacetime

    NASA Astrophysics Data System (ADS)

    Molina-Vilaplana, Javier; Sierra, Germán

    2013-12-01

    In this paper we formulate the xp model on the AdS2 spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, whose absolute values are given by a harmonic oscillator spectrum, which in turn coincides with that of a massive Dirac fermion in AdS2. We extend this result to generic xp models which are shown to be equivalent to a massive Dirac fermion on spacetimes whose metric depend of the xp Hamiltonian. Finally, we construct the generators of the isometry group SO(2,1) of the AdS2 spacetime, and discuss the relation with conformal quantum mechanics.

  16. Gastrostomy feeding tube - pump - child

    MedlinePlus

    Feeding - gastrostomy tube - pump; G-tube - pump; Gastrostomy button - pump; Bard Button - pump; MIC-KEY - pump ... Gather supplies: Feeding pump (electronic or battery powered) Feeding set that matches the feeding pump (includes a feeding bag, drip chamber, roller clamp, ...

  17. Efficacy of two elemental diets: a pair feeding study.

    PubMed

    Muggia-Sullam, M; Matarese, L E; Edwards, L L; Fischer, J E

    1986-01-01

    The efficacy and side effects of two elemental diets were studied. Twenty young Sprague-Dawley rats were fed one of three different diets. Group I (n = 7) was fed Vivonex-HN (VIV) ad lib; group II (n = 7) was given Criticare-HN (CRI), pair-fed to group I (the two elemental diets were given in glass bottles); group III was fed regular rat chow and served as control (CON). Body weight (WT), food intake, and nitrogen balance (NB) were measured daily. After 21 days, change in body weight was similar in the three groups (VIV = 64.9 +/- 3.2%; CRI = 59.6 +/- 3.3%; CON = 63.9 +/- 4.8%). Cumulative nitrogen balance was also similar in the two groups fed elemental diets (VIV = 4788 +/- 277 mg N; CRI = 4690 +/- 118 mg N), but in both these groups it was less than the control group fed chow (8060 +/- 85 mg N). Blood urea nitrogen (BUN) on the last day was higher in the VIV group (12.9 +/- 1.22 mg/dl) than in the CRI group (9.43 +/- 0.43 mg/dl), but in both study groups it was lower than in the CON group (17.2 +/- 1.08 mg/dl), although nitrogen intake was higher in the control (ad lib) group. SGPT was similar in the two elemental diets but higher than in CON. Liver weights were higher in the CRI group, probably abnormally so and likely due to increased fat content. Both diets had similar efficacy in nutritional support. PMID:3753732

  18. Determination of tilmicosin in swine feeds by liquid chromatography.

    PubMed

    Readnour, R S; Helton-Groce, S L; Dixon, S S

    1997-01-01

    This method determines tilmicosin in feeds over a concentration range of 100 to 600 mg/kg. Tilmicosin is extracted from swine feeds by adding 200 mL of a swine feed extractant (20 + 80, acetonitrile-Millipore water, pH 2.5, with 25 mM dibutylammonium phosphate) to 20 g feed and placing on a shaker table for 1 h. This extractant is filtered and analyzed by liquid chromatography (LC). A gradient LC method is used to separate tilmicosin from the feed matrix in 30 min of run time. The recovery of tilmicosin from fortified feeds ranged from 96.7 to 112%, with the coefficients of variation (CVs) ranging from 1.4 to 3.9%. The determination of tilmicosin in medicated feeds resulted in an average recovery of 92.7% of labeled claim for pelleted feeds at 200 mg/kg and 99.1% of labeled claim for mash feeds at 400 mg/kg. Determination of tilmicosin in medicated feeds resulted in CVs ranging from 2.6 to 3.8%. The method has shown no interference with 18 other drugs. PMID:9419854

  19. Value added data archiving

    NASA Technical Reports Server (NTRS)

    Berard, Peter R.

    1993-01-01

    Researchers in the Molecular Sciences Research Center (MSRC) of Pacific Northwest Laboratory (PNL) currently generate massive amounts of scientific data. The amount of data that will need to be managed by the turn of the century is expected to increase significantly. Automated tools that support the management, maintenance, and sharing of this data are minimal. Researchers typically manage their own data by physically moving datasets to and from long term storage devices and recording a dataset's historical information in a laboratory notebook. Even though it is not the most efficient use of resources, researchers have tolerated the process. The solution to this problem will evolve over the next three years in three phases. PNL plans to add sophistication to existing multilevel file system (MLFS) software by integrating it with an object database management system (ODBMS). The first phase in the evolution is currently underway. A prototype system of limited scale is being used to gather information that will feed into the next two phases. This paper describes the prototype system, identifies the successes and problems/complications experienced to date, and outlines PNL's long term goals and objectives in providing a permanent solution.

  20. ADS Development in Japan

    NASA Astrophysics Data System (ADS)

    Kikuchi, Kenji

    2010-06-01

    Accelerator driven nuclear transmutation system has been pursued to have a clue to the solution of high-level radioactive waste management. The concept consists of super conducting linac, sub-critical reactor and the beam window. Reference model is set up to 800MW thermal power by using 1.5GeV proton beams with considerations multi-factors such as core criticality. Materials damage is simulated by high-energy particle transport codes and so on. Recent achievement on irradiation materials experiment is stated and the differences are pointed out if core burn-up is considered or not. Heat balance in tank-type ADS indicates the temperature conditions of steam generator, the beam widow and cladding materials. Lead-bismuth eutectics demonstration has been conducted. Corrosion depth rate was shown by experiments.

  1. Supersymmetric warped AdS in extended topologically massive supergravity

    NASA Astrophysics Data System (ADS)

    Deger, N. S.; Kaya, A.; Samtleben, H.; Sezgin, E.

    2014-07-01

    We determine the most general form of off-shell N=(1,1) supergravity field configurations in three dimensions by requiring that at least one off-shell Killing spinor exists. We then impose the field equations of the topologically massive off-shell supergravity and find a class of solutions whose properties crucially depend on the norm of the auxiliary vector field. These are spacelike-squashed and timelike-stretched AdS3 for the spacelike and timelike norms, respectively. At the transition point where the norm vanishes, the solution is null warped AdS3. This occurs when the coefficient of the Lorentz-Chern-Simons term is related to the AdS radius by μℓ=2. We find that the spacelike-squashed AdS3 can be modded out by a suitable discrete subgroup of the isometry group, yielding an extremal black hole solution which avoids closed timelike curves.

  2. GENERAL VIEW OF TUMALO FEED CANAL (RIGHT) AND BEND FEED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW OF TUMALO FEED CANAL (RIGHT) AND BEND FEED CANAL (LEFT) INTERSECTION. LOOKING SOUTHEAST - Tumalo Irrigation District, Tumalo Project, West of Deschutes River, Tumalo, Deschutes County, OR

  3. FRACTIONAL CRYSTALLIZATION FEED ENVELOPE

    SciTech Connect

    HERTING DL

    2008-03-19

    Laboratory work was completed on a set of evaporation tests designed to establish a feed envelope for the fractional crystallization process. The feed envelope defines chemical concentration limits within which the process can be operated successfully. All 38 runs in the half-factorial design matrix were completed successfully, based on the qualitative definition of success. There is no feed composition likely to be derived from saltcake dissolution that would cause the fractional crystallization process to not meet acceptable performance requirements. However, some compositions clearly would provide more successful operation than other compositions.

  4. Coal feed lock

    DOEpatents

    Pinkel, I. Irving

    1978-01-01

    A coal feed lock is provided for dispensing coal to a high pressure gas producer with nominal loss of high pressure gas. The coal feed lock comprises a rotor member with a diametral bore therethrough. A hydraulically activated piston is slidably mounted in the bore. With the feed lock in a charging position, coal is delivered to the bore and then the rotor member is rotated to a discharging position so as to communicate with the gas producer. The piston pushes the coal into the gas producer. The rotor member is then rotated to the charging position to receive the next load of coal.

  5. Tube Feeding Troubleshooting Guide

    MedlinePlus

    ... profile tube also has a stem length). Note: NG and NJ tubes (that go through a person’s ... Immediate Action: • Discontinue feeding. • If you have an NG or NJ tube, and the tube is curled ...

  6. Breastfeeding vs. Formula Feeding

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Breastfeeding vs. Formula Feeding KidsHealth > For Parents > Breastfeeding vs. ... for you and your baby. continue All About Breastfeeding Nursing can be a wonderful experience for both ...

  7. Feeding Your Newborn

    MedlinePlus

    ... you choose to breastfeed or formula feed. About Breastfeeding Breastfeeding your newborn has many advantages. Perhaps most ... to care for her newborn. continue Limitations of Breastfeeding With all the good things known about breastfeeding, ...

  8. Chemical and textural characteristics of multistage fluid inclusions with high Li/B ratio found from the Sanbagawa belt.

    NASA Astrophysics Data System (ADS)

    Yoshida, K.; Hirajima, T.

    2012-04-01

    Recent studies invoked that the variation of peculiar fluid soluble light elements, such as Li, B and Cl, are capable of suggesting generation depths of fluid released in subduction zones (e.g., Scambelluri et al., 2004; Bebout et al., 2007; Marschall et al., 2009). Crush-leached fluids extracted from quartz veins intercalated with metabasites of the Sanbagawa metamorphic belt show high Li and B concentrations, whose Li/B ratios show a positive correlation with metamorphic grade of the host rocks, i.e., from 0.02 for pumpellyite-actinolite facies to 0.27 for eclogite facies (Sengen et al., 2009). Furthermore, crush-leached fluids extracted from quartz veins intercalated with metasediments in proximal to the eclogite unit in the Besshi district show much higher Li/B ratio (ca. 0.36-1.99). Yoshida et al. (2011) pointed out that Li/B ratio of dehydrated fluids was controlled by the rock types of the host rocks, i.e., Li/B ratio of dehydrated fluids derived from tourmaline-free metasediments show much higher values than those expected from metabasites. Those obtained data suggest that the Li/B ratio of the deep fluid has a potential as a depth indicator but there remain many unknown factors for establishing it. The Li/B ratio of extracted fluid obtained by the crush-leached method integrates the whole fluid activities which the host rocks were taken place. To investigate the fluid activity history for the sample showing the highest Li/B ratio (1.99), detailed petrographical and microthemometric studies were performed. The studied sample IR04 is a foliation-parallel quartz vein intercalated with a Grt-Hbl-Ph schist probably derived from clay, whose peak P-T conditions are estimated as 600 °C and 1.3 GPa using pseudosection analysis. The quartz vein shows a foam microstructure, suggesting that low differential stress and high-T conditions were attained during its texture formation. Three types of fluid inclusions have been identified: the earliest one, FIA-I, is

  9. Impact of sensory feed additives on feed intake, feed preferences, and growth of female piglets during the early postweaning period.

    PubMed

    Clouard, C; Val-Laillet, D

    2014-05-01

    Our study aimed at investigating the effect of feed supplementation, from weaning, with 3 sensory feed additives (FA1, FA2, and FA3) on feed preferences, feed intake, and growth of piglets. The FA1 contained extract of Stevia rebaudiana (10 to 20%), extract of high-saponin plants (5 to 10%), and excipients (70 to 85%), the FA2 was mainly composed of a natural extract of Citrus sinensis (60 to 80%), and the FA3 was made of a blend of extracts of hot-flavored spices (5 to 15%) and excipients (85 to 95%). At weaning (d 1), a total of 32 female piglets housed in individual pens were allocated to 4 treatments (FA1, FA2, FA3, and control [CON]) of equivalent mean weight. The pigs were fed a standard pelleted prestarter diet from weaning (d 1) to d 15 and a starter diet from d 16 to 28. The diets were supplemented with the feed additives (FA) corresponding to their treatment, while the CON treatment was the standard diets with no additive. Feed refusals were weighed daily and piglets were weighed weekly on d 1, 7, 14, 21, and 28. On the day of feed transition (d 16) as well as 7 (d 23) and 10 d (d 26) later, the animals were consecutively subjected to 1- and 22-h double-choice feeding tests to investigate their preferences during a short period and a longer period of time for the CON starter diet and the starter diet added with the FA corresponding to their treatment. No overall effect of the feed additives was observed on ADFI, ADG, G:F, and final BW. No overall preference was highlighted for the FA1 treatment, except for a preference for the FA1 starter diet during the 1-h test on d 23 (78% of total feed intake; P < 0.01). For the FA2 treatment, the pigs consumed the FA2 starter diet more than the CON starter diet during the 22-h tests on d 16 (67% of total feed intake; P < 0.05) and 26 (62% of total feed intake; P < 0.01). For the FA3 treatment, on d 26, the FA3 starter diet was and tended to be consumed more than the CON starter diet during 1- (69% of total intake; P

  10. Value Added in English Schools

    ERIC Educational Resources Information Center

    Ray, Andrew; McCormack, Tanya; Evans, Helen

    2009-01-01

    Value-added indicators are now a central part of school accountability in England, and value-added information is routinely used in school improvement at both the national and the local levels. This article describes the value-added models that are being used in the academic year 2007-8 by schools, parents, school inspectors, and other…

  11. Per aspirin ad astra...

    PubMed

    Hartung, Thomas

    2009-12-01

    Taking the 110th anniversary of marketing of aspirin as starting point, the almost scary toxicological profile of aspirin is contrasted with its actual use experience. The author concludes that we are lucky that, in 1899, there was no regulatory toxicology. Adding, for the purpose of this article, a fourth R to the Three Rs, i.e. Realism, three reality-checks are carried out. The first one comes to the conclusion that the tools of toxicology are hardly adequate for the challenges ahead. The second one concludes that, specifically, the implementation of the EU REACH system is not feasible with these tools, mainly with regard to throughput. The third one challenges the belief that classical alternative methods, i.e. replacing animal test-based tools one by one, is actually leading to a new toxicology - it appears to change only patches of the patchwork, but not to overcome any inherent limitations other than ethical ones. The perspective lies in the Toxicology for the 21st Century initiatives, which aim to create a new approach from the scratch, by an evidence-based toxicology and a global "Human Toxicology Programme". PMID:20105011

  12. Characteristics of stand-off detection of geological samples at MARS atmospheric pressure using laser-induced breakdown spectroscopy (LIBS).

    SciTech Connect

    Cremers, D. A.; Arp, Z. A.; Knight, Andrew K.; Scherbarth, Nancy L.; Wiens, R. C.; Maurice, S.

    2003-01-01

    LIBS has been proposed as a new method for stand-off detection of geological samples for use on landers and rovers to Mars and studies are on-going to determine capabilities. Because of the severe size, weight, ruggedness and power requirements for space instrumentation and the need to maximize scientific return, it is important to benchmark capabilities with parameters representative of compact instrumentation likely to be used in a flight instrument. Some of these issues are addressed here.

  13. Feasibility of real-time geochemical analysis using LIBS (Laser-Induced Breakdown Spectroscopy) in oil wells

    NASA Astrophysics Data System (ADS)

    Shahin, Mohamed

    2014-05-01

    The oil and gas industry has attempted for many years to find new ways to analyze and determine the type of rocks drilled on a real time basis. Mud analysis logging is a direct method of detecting oil and gas in formations drilled, it depends on the "feel" of the bit to decide formation type, as well as, geochemical analysis which was introduced 30 years ago, starting with a pulsed-neutron generator (PNG) based wireline tool upon which LWD technology was based. In this paper, we are studying the feasibility of introducing a new technology for real-time geochemical analysis. Laser-induced breakdown spectroscopy (LIBS) is a type of atomic emission spectroscopy, It is a cutting-edge technology that is used for many applications such as determination of alloy composition, origin of manufacture (by monitoring trace components), and molecular analysis (unknown identification). LIBS can analyze any material regardless of its state (solid, liquid or gas), based upon that fact, we can analyze rocks, formation fluids' types and contacts between them. In cooperation with the National Institute of Laser Enhanced Science, Cairo University in Egypt, we've done tests on sandstone, limestone and coal samples acquired from different places using Nd: YAG Laser with in addition to other components that are explained in details through this paper to understand the ability of Laser to analyze rock samples and provide their elemental composition using LIBS technique. We've got promising results from the sample analysis via LIBS and discussed the possibility of deploying this technology in oilfields suggesting many applications and giving a base for achieving a quantitative elemental analysis method in view of its shortcomings and solutions.

  14. Impact of feeding on growth performance, blood biochemical and mineral profiles of pre-pubescent camels under pastoral management in arid western Rajasthan.

    PubMed

    Saini, Nirmala; Kiradoo, Baldev Dass; Bohra, Dau Lal

    2014-08-01

    The experiment was undertaken on 20 pre-pubescent dromedary camels of 300 ± 7.0 kg average bodyweight (BW) and 1.5-2 years of age to determine change in body weight, blood biochemical and mineral profiles and morphometric parameters on rangeland grazing (GR) and supplementary stall feeding (GS) at arid northwestern part of Rajasthan over a period of 80 days. GR camels were maintained only on grazing, while GS camels were fed semi-intensively ad-lib groundnut haulms along with formulated concentrate and mineral mixture to meet maintenance requirement. Intake of young camels was determined using chromium(III) oxide as internal marker. The biomass yield of rangeland estimated was 0.54 t DM/ha. Dry matter intake (kg/day) by GR camels on rangeland grazing was lower than that by GS camels fed on supplementary feeding. The nutrient digestibility of dry matter and organic matter (P < 0.05) and crude protein was higher in GS camels than that in GR camels. Likewise, intake of digestible crude protein (P < 0.05) and metabolizable energy were higher in stall-fed young camels. Pre-pubescent camels fed on grazing had significantly (P < 0.01) low glucose and higher urea concentration compared to stall-fed camels. Final body weight of camels differed significantly (P < 0.05) between groups. The camels fed on supplementary stall feeding had significantly (P < 0.01) higher total gain (kg) and average daily gain (ADG) compared to camels on grazing. Among morphometric parameters, body length and body height showed more significant increase in GS compared to GR camels. Intake of digestible crude protein (DCP) by GR group was 43% low compared to the requirement for growing camel of 300 kg body weight. Despite this, GR camels were able to maintain body weight due to better recycling of urea which was significantly higher in comparison to GS camels. The findings of significantly (P < 0.01) low serum glucose and higher urea concentration and lower body weight

  15. Multi-Pulse Excitation for Underwater Analysis of Copper-Based Alloys Using a Novel Remote Laser-Induced Breakdown Spectroscopy (LIBS) System.

    PubMed

    Guirado, Salvador; Fortes, Francisco J; Laserna, J Javier

    2016-04-01

    In this work, the use of multi-pulse excitation has been evaluated as an effective solution to mitigate the preferential ablation of the most volatile elements, namely Sn, Pb, and Zn, observed during laser-induced breakdown spectroscopy (LIBS) analysis of copper-based alloys. The novel remote LIBS prototype used in this experiments featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The remote instrument is capable of performing chemical analysis of submersed materials up to a depth of 50 m. Laser-induced breakdown spectroscopy analysis was performed at air pressure settings simulating the conditions during a real subsea analysis. A set of five certified bronze standards with variable concentration of Cu, As, Sn, Pb, and Zn were used. In SP-LIBS, signal emission is strongly sensitive to ambient pressure. In this case, fractionation effect was observed. Multi-pulse excitation circumvents the effect of pressure over the quantitative analysis, thus avoiding the fractionation phenomena observed in single pulse LIBS. The use of copper as internal standard minimizes matrix effects and discrepancies due to variation in ablated mass. PMID:26957105

  16. Homogeneity testing and quantitative analysis of manganese (Mn) in vitrified Mn-doped glasses by laser-induced breakdown spectroscopy (LIBS)

    SciTech Connect

    Unnikrishnan, V. K.; Nayak, Rajesh; Kartha, V. B.; Santhosh, C. E-mail: unnikrishnan.vk@manipal.edu; Sonavane, M. S.; Yeotikar, R. G.; Shah, M. L.; Gupta, G. P.; Suri, B. M.

    2014-09-15

    Laser-induced breakdown spectroscopy (LIBS), an atomic emission spectroscopy method, has rapidly grown as one of the best elemental analysis techniques over the past two decades. Homogeneity testing and quantitative analysis of manganese (Mn) in manganese-doped glasses have been carried out using an optimized LIBS system employing a nanosecond ultraviolet Nd:YAG laser as the source of excitation. The glass samples have been prepared using conventional vitrification methods. The laser pulse irradiance on the surface of the glass samples placed in air at atmospheric pressure was about 1.7×10{sup 9} W/cm{sup 2}. The spatially integrated plasma emission was collected and imaged on to the spectrograph slit using an optical-fiber-based collection system. Homogeneity was checked by recording LIBS spectra from different sites on the sample surface and analyzing the elemental emission intensities for concentration determination. Validation of the observed LIBS results was done by comparison with scanning electron microscope- energy dispersive X-ray spectroscopy (SEM-EDX) surface elemental mapping. The analytical performance of the LIBS system has been evaluated through the correlation of the LIBS determined concentrations of Mn with its certified values. The results are found to be in very good agreement with the certified concentrations.

  17. Analysis of heterogeneous gallstones using laser-induced breakdown spectroscopy (LIBS) and wavelength dispersive X-ray fluorescence (WD-XRF).

    PubMed

    Jaswal, Brij Bir S; Kumar, Vinay; Sharma, Jitendra; Rai, Pradeep K; Gondal, Mohammed A; Gondal, Bilal; Singh, Vivek K

    2016-04-01

    Laser-induced breakdown spectroscopy (LIBS) is an emerging analytical technique with numerous advantages such as rapidity, multi-elemental analysis, no specific sample preparation requirements, non-destructiveness, and versatility. It has been proven to be a robust elemental analysis tool attracting interest because of being applied to a wide range of materials including biomaterials. In this paper, we have performed spectroscopic studies on gallstones which are heterogeneous in nature using LIBS and wavelength dispersive X-ray fluorescence (WD-XRF) techniques. It has been observed that the presence and relative concentrations of trace elements in different kind of gallstones (cholesterol and pigment gallstones) can easily be determined using LIBS technique. From the experiments carried out on gallstones for trace elemental mapping and detection, it was found that LIBS is a robust tool for such biomedical applications. The stone samples studied in the present paper were classified using the Fourier transform infrared (FTIR) spectroscopy. WD-XRF spectroscopy has been applied for the qualitative and quantitative analysis of major and trace elements present in the gallstone which was compared with the LIBS data. The results obtained in the present paper show interesting prospects for LIBS and WD-XRF to study cholelithiasis better. PMID:26886588

  18. Line selection and parameter optimization for trace analysis of uranium in glass matrices by laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Choi, Inhee; Chan, George C-Y; Mao, Xianglei; Perry, Dale L; Russo, Richard E

    2013-11-01

    Laser-induced breakdown spectroscopy (LIBS) has been evaluated for the determination of uranium in real-world samples such as uraninite. NIST Standard Reference Materials were used to evaluate the spectral interferences on detection of uranium. The study addresses the detection limit of LIBS for several uranium lines and their relationship to non-uranium lines, with emphasis on spectral interferences. The data are discussed in the context of optimizing the choice of emission lines for both qualitative and quantitative analyses from a complex spectrum of uranium in the presence of other elements. Temporally resolved spectral emission intensities, line width, and line shifts were characterized to demonstrate the parameter influence on these measurements. The measured uranium line width demonstrates that LIBS acquired with moderately high spectral resolution (e.g., by a 1.25 m spectrometer with a 2400 grooves/mm grating) can be utilized for isotope shift measurements in air at atmospheric pressure with single to tens of parts per million (ppm) level detection limits, as long as an appropriate transition is chosen for analysis. PMID:24160879

  19. Classification of red wine based on its protected designation of origin (PDO) using Laser-induced Breakdown Spectroscopy (LIBS).

    PubMed

    Moncayo, S; Rosales, J D; Izquierdo-Hornillos, R; Anzano, J; Caceres, J O

    2016-09-01

    This work reports on a simple and fast classification procedure for the quality control of red wines with protected designation of origin (PDO) by means of Laser Induced Breakdown Spectroscopy (LIBS) technique combined with Neural Networks (NN) in order to increase the quality assurance and authenticity issues. A total of thirty-eight red wine samples from different PDO were analyzed to detect fake wines and to avoid unfair competition in the market. LIBS is well known for not requiring sample preparation, however, in order to increase its analytical performance a new sample preparation treatment by previous liquid-to-solid transformation of the wine using a dry collagen gel has been developed. The use of collagen pellets allowed achieving successful classification results, avoiding the limitations and difficulties of working with aqueous samples. The performance of the NN model was assessed by three validation procedures taking into account their sensitivity (internal validation), generalization ability and robustness (independent external validation). The results of the use of a spectroscopic technique coupled with a chemometric analysis (LIBS-NN) are discussed in terms of its potential use in the food industry, providing a methodology able to perform the quality control of alcoholic beverages. PMID:27343593

  20. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed....

  1. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed....

  2. 31 CFR 540.317 - Uranium feed; natural uranium feed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed....

  3. Reconstructing Ancient Egyptian Diet through Bone Elemental Analysis Using LIBS (Qubbet el Hawa Cemetery).

    PubMed

    Al-Khafif, Ghada Darwish; El-Banna, Rokia

    2015-01-01

    One of the most important advantages of LIBS that make it suitable for the analysis of archeological materials is that it is a quasi-nondestructive technique. Archeological mandibles excavated from Qubbet el Hawa Cemetery, Aswan, were subjected to elemental analysis in order to reconstruct the dietary patterns of the middle class of the Aswan population throughout three successive eras: the First Intermediate Period (FIP), the Middle Kingdom (MK), and the Second Intermediate Period (SIP). The bone Sr/Ca and Ba/Ca ratios were significantly correlated, so the Sr/Ca ratios are considered to represent the ante-mortem values. It was suggested that the significantly low FIP Sr/Ca compared to that of both the MK and the SIP was attributed to the consumption of unusual sorts of food and imported cereals during years of famine, while the MK Sr/Ca was considered to represent the amelioration of climatic, social, economic, and political conditions in this era of state socialism. The SIP Sr/Ca, which is nearly the same as that of the MK, was considered to be the reflection of the continuity of the individualism respect and state socialism and a reflection of agriculture conditions amelioration under the reign of the 17th Dynasty in Upper Egypt. PMID:26345727

  4. Qualitative analysis of Pb liquid sample using laser-induced breakdown spectroscopy (LIBS)

    SciTech Connect

    Suyanto, Hery; Rupiasih, Ni Nyoman; Winardi, T. B.; Manurung, M.; Kurniawan, K. H.

    2013-09-03

    Qualitative analysis of liquid sample containing 1,000 ppm of Pb was performed by using LIBS technique. In order to avoid splashing off of the liquid sample during laser irradiation, a sample pretreatment was done, namely the liquid sample was absorbed by using commercial available stomach medicine. Two kinds of absorbent materials were chosen in this experiment, first containing 125 mg activated carbon and second 600 mg activated attapulgite. These absorbent materials were used since carbon sample gives better absorption of infrared laser irradiation used in this experiment. In order to characterize the absorption process, three treatments were conducted in this experiment; first, without heating the sample but varying the absorption time before laser irradiation; second by varying the heating temperature after certain time of absorption process and third by varying the temperature only. The maximum emission intensity of Pb I 405.7 nm was found in the second treatment of heating the sample till 85°C after 30 minutes absorption of the liquid sample in both absorbent materials.

  5. Analyzing toys models of Arabidopsis and Drosphila using Z3 SMT-LIB

    NASA Astrophysics Data System (ADS)

    Rodríguez Vega, Martín.

    2014-05-01

    Toy models for the Arabidopsis Thaliana flower and the Drosophila are analyzed using Microsoft SMT-Solver Z3 with the SMT-LIB language. The models are formulated as Boolean networks which describe the metabolic cycles for Arabidopsis and Drosophila. The dynamic activation of the different bio macromolecules is described by the variables and laws of Boolean transition. Specifically, bitvectors and assertions, which describe the change of state of bitvectors from a sampling time to the next, are used. The dynamic feasibility problem of the biological network is translated to a Boolean satisfiability problem. The corresponding dynamic attractors are represented as a model of satisfiability. The Z3 software allows all required computations in a friendly and efficient manner. It is expected that the SMT-solvers, such as Z3, will become a routine tool in system biology and that they will provide bio-nanosystem design techniques. As a line for future research, the study of the models for Arabidopsis and Drosophila using different SMT-solvers such as CVC4, Mathsat and Yices, is proposed.

  6. LIBS data analysis using a predictor-corrector based digital signal processor algorithm

    NASA Astrophysics Data System (ADS)

    Sanders, Alex; Griffin, Steven T.; Robinson, Aaron

    2012-06-01

    There are many accepted sensor technologies for generating spectra for material classification. Once the spectra are generated, communication bandwidth limitations favor local material classification with its attendant reduction in data transfer rates and power consumption. Transferring sensor technologies such as Cavity Ring-Down Spectroscopy (CRDS) and Laser Induced Breakdown Spectroscopy (LIBS) require effective material classifiers. A result of recent efforts has been emphasis on Partial Least Squares - Discriminant Analysis (PLS-DA) and Principle Component Analysis (PCA). Implementation of these via general purpose computers is difficult in small portable sensor configurations. This paper addresses the creation of a low mass, low power, robust hardware spectra classifier for a limited set of predetermined materials in an atmospheric matrix. Crucial to this is the incorporation of PCA or PLS-DA classifiers into a predictor-corrector style implementation. The system configuration guarantees rapid convergence. Software running on multi-core Digital Signal Processor (DSPs) simulates a stream-lined plasma physics model estimator, reducing Analog-to-Digital (ADC) power requirements. This paper presents the results of a predictorcorrector model implemented on a low power multi-core DSP to perform substance classification. This configuration emphasizes the hardware system and software design via a predictor corrector model that simultaneously decreases the sample rate while performing the classification.

  7. Reconstructing Ancient Egyptian Diet through Bone Elemental Analysis Using LIBS (Qubbet el Hawa Cemetery)

    PubMed Central

    Al-Khafif, Ghada Darwish; El-Banna, Rokia

    2015-01-01

    One of the most important advantages of LIBS that make it suitable for the analysis of archeological materials is that it is a quasi-nondestructive technique. Archeological mandibles excavated from Qubbet el Hawa Cemetery, Aswan, were subjected to elemental analysis in order to reconstruct the dietary patterns of the middle class of the Aswan population throughout three successive eras: the First Intermediate Period (FIP), the Middle Kingdom (MK), and the Second Intermediate Period (SIP). The bone Sr/Ca and Ba/Ca ratios were significantly correlated, so the Sr/Ca ratios are considered to represent the ante-mortem values. It was suggested that the significantly low FIP Sr/Ca compared to that of both the MK and the SIP was attributed to the consumption of unusual sorts of food and imported cereals during years of famine, while the MK Sr/Ca was considered to represent the amelioration of climatic, social, economic, and political conditions in this era of state socialism. The SIP Sr/Ca, which is nearly the same as that of the MK, was considered to be the reflection of the continuity of the individualism respect and state socialism and a reflection of agriculture conditions amelioration under the reign of the 17th Dynasty in Upper Egypt. PMID:26345727

  8. Reliable classification of moving waste materials with LIBS in concrete recycling.

    PubMed

    Xia, Han; Bakker, M C M

    2014-03-01

    Effective discrimination between different waste materials is of paramount importance for inline quality inspection of recycle concrete aggregates from demolished buildings. The moving targeted materials in the concrete waste stream are wood, PVC, gypsum block, glass, brick, steel rebar, aggregate and cement paste. For each material, up to three different types were considered, while thirty particles of each material were selected. Proposed is a reliable classification methodology based on integration of the LIBS spectral emissions in a fixed time window, starting from the deployment of the laser shot. PLS-DA (multi class) and the hybrid combination PCA-Adaboost (binary class) were investigated as efficient classifiers. In addition, mean centre and auto scaling approaches were compared for both classifiers. Using 72 training spectra and 18 test spectra per material, each averaged by ten shots, only PLS-DA achieved full discrimination, and the mean centre approach made it slightly more robust. Continuing with PLS-DA, the relation between data averaging and convergence to 0.3% average error was investigated using 9-fold cross-validations. Single-shot PLS-DA presented the highest challenge and most desirable methodology, which converged with 59 PC. The degree of success in practical testing will depend on the quality of the training set and the implications of the possibly remaining false positives. PMID:24468365

  9. Picosecond LIBS diagnostics for Tokamak in situ plasma facing materials chemical analysis

    NASA Astrophysics Data System (ADS)

    Morel, Vincent; Pérès, Bastien; Bultel, Arnaud; Hideur, Ammar; Grisolia, Christian

    2016-02-01

    First results are presented in relation with experimental and theoretical studies performed at the CORIA laboratory in the general framework of the determination of the chemical analysis of Tokamak plasma facing materials by laser-induced breakdown spectroscopy (LIBS) in picosecond regime. Experiments are performed on W in a specific chamber. This chamber is equipped with a UV-visible-near IR spectroscopic device. Boltzmann plots are derived for typical laser characteristics. We show that the initial excitation temperature is close to 12 000 K followed by a quasi steady value close to 8500 K. The ECHREM (Euler code for CHemically REactive Multicomponent laser-induced plasmas) code is developed to reproduce the laser-induced plasmas. This code is based on the implementation of a Collisional-Radiative model in which the different excited states are considered as full species. This state-to-state approach is relevant to theoretically assess the departure from excitation and chemical equilibrium. Tested on aluminum, the model shows that the plasma remains close to excitation equilibrium.

  10. Using the LibCF/GRIDSPEC extensions to interpret data on mosaic grids with CDAT

    NASA Astrophysics Data System (ADS)

    Kindig, D.; Pletzer, A.; Balaji, V.; Hankin, S. C.; Hartnett, E. J.; Doutriaux, C.; Painter, J.; Sobol, A.; Wrobel, M.

    2010-12-01

    Increasingly earth system models perform computations on grids that are not describable as simple, rectangular arrays (e.g. lon by lat), instead requiring a mosaic of interacting, logically rectangular tiles. Such grids are developed for a variety of reasons that include removal of coordinate singularities that may degrade numerical reliability in a region of interest (e.g. the north pole in an ocean model) and increasing the uniformity of numerical precision over the globe. Coupled earth system models, typically characterized by independent coordinate reference systems for modeling atmosphere, ocean, ice, and terrestrial processes, are themselves examples of such mosaic grids. GRIDSPEC is a proposed set of conventions to the Climate and Forecast library (LibCF) describing data on mosaic grids developed by V. Balaji et al. (Geophysical Fluid Dynamics Laboratory). It supports unstructured assemblies of structured grids, including the cubed-sphere and tripolar meshes. Here we review a GRIDSPEC NetCDF format based on host, contact, grid, and data files. We will show how mosaic grids can be created from the ground up using a C API and the Python Climate Data Anaysis Tools (CDAT) for visualization. As an application we use GRIDSPEC to regrid cubed-sphere data onto a longitude-latitude grid.

  11. Point defects in lithium triborate (LiB3O5) crystals

    NASA Astrophysics Data System (ADS)

    Scripsick, M. P.; Fang, X. H.; Edwards, G. J.; Halliburton, L. E.; Tyminski, J. K.

    1993-02-01

    Electron paramagnetic resonance (EPR), electron-nuclear double resonance, optical absorption, and thermoluminescence have been used to investigate radiation-induced point defects in a single crystal of lithium triborate (LiB3O5). Two prominent defects are observed after irradiation near liquid-nitrogen temperature with 60 kV x rays. A four-line EPR spectrum, with 12.2 G splittings, is assigned to a trapped-hole center, and another four-line EPR spectrum, with 120 G splittings, is assigned to a trapped-electron center. In each case, the nucleus responsible for the observed hyperfine is 11B. The trapped hole is localized on an oxygen ion and has a weak hyperfine interaction with one neighboring boron nucleus, whereas the trapped electron is localized primarily on a boron ion with a correspondingly larger hyperfine interaction. Both defects become thermally unstable near 125 K, and their decay (i.e., recombination) correlates with an intense thermoluminescence peak at this same temperature. An optical absorption peak at 300 nm is produced by the x rays and thermally decays at the same temperatures as the EPR spectra.

  12. Characterization of LiB(3)O(5) crystal for second-harmonic generation.

    PubMed

    Xie, F; Wu, B; You, G; Chen, C

    1991-08-15

    We present second-harmonic generation characteristics of LiB(3)O(5) (LBO) crystal with different phase-matching lengths and comparison with those of beta-BaB(2)O(4) crystal. A computer program of the numerical interaction method was adopted to make the theoretical calculation of second-harmonic generation conversion efficiencies of LBO with different phase-matching lengths and power densities of the fundamental beam of a Nd:YAG laser, and the calculated result was compared with the experimental one. It is seen from the calculated and experimental results that for certain power densities of the fundamental laser beam, so long as the length of the LBO crystal is selected appropriately, a high energy conversion efficiency could be obtained. For example, an optimal external energy conversion efficiency of LBO crystal of more than 70% has been attained for several 100-MW/cm(2) fundamental laser beams. Experiments also showed that the crystal could be used under high power densities without any damage to the surface and the interior. PMID:19776930

  13. Supergravity at the boundary of AdS supergravity

    NASA Astrophysics Data System (ADS)

    Amsel, Aaron J.; Compère, Geoffrey

    2009-04-01

    We give a general analysis of AdS boundary conditions for spin-3/2 Rarita-Schwinger fields and investigate boundary conditions preserving supersymmetry for a graviton multiplet in AdS4. Linear Rarita-Schwinger fields in AdSd are shown to admit mixed Dirichlet-Neumann boundary conditions when their mass is in the range 0≤|m|<1/2lAdS. We also demonstrate that mixed boundary conditions are allowed for larger masses when the inner product is “renormalized” accordingly with the action. We then use the results obtained for |m|=1/lAdS to explore supersymmetric boundary conditions for N=1 AdS4 supergravity in which the metric and Rarita-Schwinger fields are fluctuating at the boundary. We classify boundary conditions that preserve boundary supersymmetry or superconformal symmetry. Under the AdS/CFT dictionary, Neumann boundary conditions in d=4 supergravity correspond to gauging the superconformal group of the three-dimensional CFT describing M2-branes, while N=1 supersymmetric mixed boundary conditions couple the CFT to N=1 superconformal topologically massive gravity.

  14. Milk traits of lactating cows submitted to feed restriction.

    PubMed

    Gabbi, Alexandre Mossate; McManus, Concepta Margareth; Zanela, Maira Balbinotti; Stumpf, Marcelo Tempel; Barbosa, Rosângela Silveira; Fruscalso, Vilmar; Thaler Neto, André; Schmidt, Fernando André; Fischer, Vivian

    2016-01-01

    Data from five experiments with dairy cows where feed was restricted to 0, 40, and 50% of the ad libitum amount, with 259 observations, were subjected to multivariate analyses to determine the effects of severity and duration of feed restriction on production, physical-chemical characteristics, ethanol stability, and somatic cell score of milk. A negative relationship was seen between the severity and duration of feed restriction with milk production, lactose content, titratable acidity, and milk stability to the ethanol test. The milk stability to the ethanol test, protein content, milk yield, and somatic cells score were the most important attributes retained by the discriminant analysis. Milk stability to the ethanol test, live weight, days in restriction, and pH were the most important characteristics explaining the variance within the different levels of feed restriction. Milk production and ethanol stability were significantly lower in both levels of feed restriction compared with the group fed ad libitum. When feed restriction was followed by refeeding, the difference observed in ethanol stability was the first discriminant variable, followed by the difference in unstable milk frequency and titratable acidity. Increments in the severity and duration of feed restriction negatively affect milk production and milk ethanol stability. PMID:26385460

  15. Asymptotically AdS spacetimes with a timelike Kasner singularity

    NASA Astrophysics Data System (ADS)

    Ren, Jie

    2016-07-01

    Exact solutions to Einstein's equations for holographic models are presented and studied. The IR geometry has a timelike cousin of the Kasner singularity, which is the less generic case of the BKL (Belinski-Khalatnikov-Lifshitz) singularity, and the UV is asymptotically AdS. This solution describes a holographic RG flow between them. The solution's appearance is an interpolation between the planar AdS black hole and the AdS soliton. The causality constraint is always satisfied. The entanglement entropy and Wilson loops are discussed. The boundary condition for the current-current correlation function and the Laplacian in the IR is examined. There is no infalling wave in the IR, but instead, there is a normalizable solution in the IR. In a special case, a hyperscaling-violating geometry is obtained after a dimensional reduction.

  16. All AdS7 solutions of type II supergravity

    NASA Astrophysics Data System (ADS)

    Apruzzi, Fabio; Fazzi, Marco; Rosa, Dario; Tomasiello, Alessandro

    2014-04-01

    In M-theory, the only AdS7 supersymmetric solutions are AdS7 × S 4 and its orbifolds. In this paper, we find and classify new supersymmetric solutions of the type AdS7 × M 3 in type II supergravity. While in IIB none exist, in IIA with Romans mass (which does not lift to M-theory) there are many new ones. We use a pure spinor approach reminiscent of generalized complex geometry. Without the need for any Ansatz, the system determines uniquely the form of the metric and fluxes, up to solving a system of ODEs. Namely, the metric on M 3 is that of an S 2 fibered over an interval; this is consistent with the Sp(1) R-symmetry of the holographically dual (1,0) theory. By including D8 brane sources, one can numerically obtain regular solutions, where topologically M 3 ≅ S 3.

  17. Worldsheet scattering in AdS3/CFT2

    NASA Astrophysics Data System (ADS)

    Sundin, Per; Wulff, Linus

    2013-07-01

    We confront the recently proposed exact S-matrices for AdS 3/ CFT 2 with direct worldsheet calculations. Utilizing the BMN and Near Flat Space (NFS) expansions for strings on AdS 3 × S 3 × S 3 × S 1 and AdS 3 × S 3 × T 4 we compute both tree-level and one-loop scattering amplitudes. Up to some minor issues we find nice agreement in the tree-level sector. At the one-loop level however we find that certain non-zero tree-level processes, which are not visible in the exact solution, contribute, via the optical theorem, and give an apparent mismatch for certain amplitudes. Furthermore we find that a proposed one-loop modification of the dressing phase correctly reproduces the worldsheet calculation while the standard Hernandez-Lopez phase does not. We also compute several massless to massless processes.

  18. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    NASA Astrophysics Data System (ADS)

    Evnin, Oleg; Jai-akson, Puttarak

    2016-04-01

    We present a range of methods suitable for accurate evaluation of the leading asymptotics for integrals of products of Jacobi polynomials in limits when the degrees of some or all polynomials inside the integral become large. The structures in question have recently emerged in the context of effective descriptions of small amplitude perturbations in anti-de Sitter (AdS) spacetime. The limit of high degree polynomials corresponds in this situation to effective interactions involving extreme short-wavelength modes, whose dynamics is crucial for the turbulent instabilities that determine the ultimate fate of small AdS perturbations. We explicitly apply the relevant asymptotic techniques to the case of a self-interacting probe scalar field in AdS and extract a detailed form of the leading large degree behavior, including closed form analytic expressions for the numerical coefficients appearing in the asymptotics.

  19. New massive gravity and AdS(4) counterterms.

    PubMed

    Jatkar, Dileep P; Sinha, Aninda

    2011-04-29

    We show that the recently proposed Dirac-Born-Infeld extension of new massive gravity emerges naturally as a counterterm in four-dimensional anti-de Sitter space (AdS(4)). The resulting on-shell Euclidean action is independent of the cutoff at zero temperature. We also find that the same choice of counterterm gives the usual area law for the AdS(4) Schwarzschild black hole entropy in a cutoff-independent manner. The parameter values of the resulting counterterm action correspond to a c=0 theory in the context of the duality between AdS(3) gravity and two-dimensional conformal field theory. We rewrite this theory in terms of the gauge field that is used to recast 3D gravity as a Chern-Simons theory. PMID:21635026

  20. Phases of global AdS black holes

    NASA Astrophysics Data System (ADS)

    Basu, Pallab; Krishnan, Chethan; Subramanian, P. N. Bala

    2016-06-01

    We study the phases of gravity coupled to a charged scalar and gauge field in an asymptotically Anti-de Sitter spacetime ( AdS 4) in the grand canonical ensemble. For the conformally coupled scalar, an intricate phase diagram is charted out between the four relevant solutions: global AdS, boson star, Reissner-Nordstrom black hole and the hairy black hole. The nature of the phase diagram undergoes qualitative changes as the charge of the scalar is changed, which we discuss. We also discuss the new features that arise in the extremal limit.

  1. The forecaster's added value

    NASA Astrophysics Data System (ADS)

    Turco, M.; Milelli, M.

    2009-09-01

    skill scores of two competitive forecast. It is important to underline that the conclusions refer to the analysis of the Piemonte operational alert system, so they cannot be directly taken as universally true. But we think that some of the main lessons that can be derived from this study could be useful for the meteorological community. In details, the main conclusions are the following: - despite the overall improvement in global scale and the fact that the resolution of the limited area models has increased considerably over recent years, the QPF produced by the meteorological models involved in this study has not improved enough to allow its direct use, that is, the subjective HQPF continues to offer the best performance; - in the forecast process, the step where humans have the largest added value with respect to mathematical models, is the communication. In fact the human characterisation and communication of the forecast uncertainty to end users cannot be replaced by any computer code; - eventually, although there is no novelty in this study, we would like to show that the correct application of appropriated statistical techniques permits a better definition and quantification of the errors and, mostly important, allows a correct (unbiased) communication between forecasters and decision makers.

  2. Mystery cloud of AD 536

    NASA Technical Reports Server (NTRS)

    Stothers, R. B.

    1984-01-01

    The possible cause of the densest and most persistent dry fog on record, which was observed in Europe and the Middle East during AD 536 and 537, is discussed. The fog's long duration toward the south and the high sulfuric acid signal detected in Greenland in ice cores dated around AD 540 support the theory that the fog was due to the explosion of the Rabaul volcano, the occurrence of which has been dated at about AD 540 by the radiocarbon method.

  3. AdS Branes from Partial Breaking of Superconformal Symmetries

    SciTech Connect

    Ivanov, E.A.

    2005-10-01

    It is shown how the static-gauge world-volume superfield actions of diverse superbranes on the AdS{sub d+1} superbackgrounds can be systematically derived from nonlinear realizations of the appropriate AdS supersymmetries. The latter are treated as superconformal symmetries of flat Minkowski superspaces of the bosonic dimension d. Examples include the N = 1 AdS{sub 4} supermembrane, which is associated with the 1/2 partial breaking of the OSp(1|4) supersymmetry down to the N = 1, d = 3 Poincare supersymmetry, and the T-duality related L3-brane on AdS{sub 5} and scalar 3-brane on AdS{sub 5} x S{sup 1}, which are associated with two different patterns of 1/2 breaking of the SU(2, 2|1) supersymmetry. Another (closely related) topic is the AdS/CFT equivalence transformation. It maps the world-volume actions of the codimension-one AdS{sub d+1} (super)branes onto the actions of the appropriate Minkowski (super)conformal field theories in the dimension d.

  4. AdS5 backgrounds with 24 supersymmetries

    NASA Astrophysics Data System (ADS)

    Beck, S.; Gutowski, J.; Papadopoulos, G.

    2016-06-01

    We prove a non-existence theorem for smooth AdS 5 solutions with connected, compact without boundary internal space that preserve strictly 24 supersymmetries. In particular, we show that D = 11 supergravity does not admit such solutions, and that all such solutions of IIB supergravity are locally isometric to the AdS 5 × S 5 maximally supersymmetric background. Furthermore, we prove that (massive) IIA supergravity also does not admit such solutions, provided that the homogeneity conjecture for massive IIA supergravity is valid. In the context of AdS/CFT these results imply that if gravitational duals for strictly mathcal{N}=3 superconformal theories in 4-dimensions exist, they are either singular or their internal spaces are not compact.

  5. Entanglement temperature and perturbed AdS3 geometry

    NASA Astrophysics Data System (ADS)

    Levine, G. C.; Caravan, B.

    2016-06-01

    Generalizing the first law of thermodynamics, the increase in entropy density δ S (x ) of a conformal field theory (CFT) is proportional to the increase in energy density, δ E (x ) , of a subsystem divided by a spatially dependent entanglement temperature, TE(x ) , a fixed parameter determined by the geometry of the subsystem, crossing over to thermodynamic temperature at high temperatures. In this paper we derive a generalization of the thermodynamic Clausius relation, showing that deformations of the CFT by marginal operators are associated with spatial temperature variations, δ TE(x ) , and spatial energy correlations play the role of specific heat. Using AdS/CFT duality we develop a relationship between a perturbation in the local entanglement temperature of the CFT and the perturbation of the bulk AdS metric. In two dimensions, we demonstrate a method through which direct diagonalizations of the boundary quantum theory may be used to construct geometric perturbations of AdS3 .

  6. [Supplementation of swine feed rations with zeolite during cage rearing].

    PubMed

    Bartko, P; Chabada, J; Vrzgula, L; Solár, I; Blazovský, J

    1983-07-01

    The effect of the addition of zeolite to pig feed ration was studied in the cage rearing system under production conditions. Zeolite was mixed in the COS I and COS II feed mixtures directly in the feed plant, the mixing ratio being 100 kg feed mixture + 5 kg zeolite. The feed mixture was administered in granular form ad libitum. The test group had 648 weanlings and the control group 674 weanlings; the piglets, kept in two-story cages in four sections, were arranged so that the test group could be a mirror-like reflection of the control group. The trial lasted 45 days. The piglets given the fortified feed ration had daily weight gains higher by 0.017 kg and feed consumption lower by 0.234 kg per 1 kg of gain, as compared with the control animals. The costs of the feed ration required for producing a kilogram of gain were 8.55 Cz. crowns in the zeolite group and 9.422 crowns in the control group. PMID:6312666

  7. Feeding of Diarmis Proboscis

    ERIC Educational Resources Information Center

    Young, Jocelyn

    2005-01-01

    The feeding of Diarmis proboscis is an exciting outdoor laboratory activity that demonstrates a single concept of adaptations--cryptic colorations. The students are "transformed" into D. proboscis (no Harry Potter magic needed) in order to learn how adaptations work in the natural world. Prior to beginning this activity, students should have a…

  8. Dust feed mechanism

    DOEpatents

    Milliman, Edward M.

    1984-01-01

    The invention is a dust feed device for delivery of a uniform supply of dust for long periods of time to an aerosolizing means for production of a dust suspension. The device utilizes at least two tandem containers having spiral brushes within the containers which transport the dust from a supply to the aerosolizer means.

  9. Infant feeding and vision

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past several years, a number of randomized controlled trials have compared the effects of breastfeeding and formula feeding and the effects of docosahexaenoic acid (DHA)–supplemented and non-supplemented formulas on visual function in both preterm and term infants. Some studies have shown b...

  10. Feed Your Brain!

    ERIC Educational Resources Information Center

    Failmezger, Tammie L.

    2006-01-01

    Language arts teachers and library media specialists bear the responsibility of teaching students how to properly feed their brains. In this article, the author describes how she teaches her students to make wise choices when selecting books. Furthermore, she presents the "Brain Food Pyramid" model that looks similar to the food pyramid but it…

  11. ASDC RSS Feeds

    Atmospheric Science Data Center

    2013-03-08

    ... having to visit each one of them to see what's new. When you sign up, you receive breaking news on your computer as soon as it is released. How can I sign up? Select the link(s) above to view our "raw" RSS feed. In ...

  12. Feeding DDGS to Finfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Globally, aquaculture has been growing at a rapid pace (currently 8.5% per year) over the past two decades, and is recognized as the fastest growing food production sector of agriculture in the U.S. Growth of aquaculture and other industries (e.g., other monogastric and ruminant livestock feed appl...

  13. SUPERCONDUCTING OPEN-GRADIENT MAGNETIC SEPARATION FOR THE PRETREATMENT OF RADIOACTIVE OR MIXED WASTE VITRIFICATION FEEDS

    EPA Science Inventory

    Scientists need to gain a better understanding of the magnetic separation processes that can be used to separate deleterious constituents (crystalline, amorphous, and colloidal) in vitrification feed streams for borosilicate glass production without adding chemicals or generating...

  14. Lorentzian AdS geometries, wormholes, and holography

    SciTech Connect

    Arias, Raul E.; Silva, Guillermo A.; Botta Cantcheff, Marcelo

    2011-03-15

    We investigate the structure of two-point functions for the quantum field theory dual to an asymptotically Lorentzian Anti de Sitter (AdS) wormhole. The bulk geometry is a solution of five-dimensional second-order Einstein-Gauss-Bonnet gravity and causally connects two asymptotically AdS spacetimes. We revisit the Gubser-Klebanov-Polyakov-Witten prescription for computing two-point correlation functions for dual quantum field theories operators O in Lorentzian signature and we propose to express the bulk fields in terms of the independent boundary values {phi}{sub 0}{sup {+-}} at each of the two asymptotic AdS regions; along the way we exhibit how the ambiguity of normalizable modes in the bulk, related to initial and final states, show up in the computations. The independent boundary values are interpreted as sources for dual operators O{sup {+-}} and we argue that, apart from the possibility of entanglement, there exists a coupling between the degrees of freedom living at each boundary. The AdS{sub 1+1} geometry is also discussed in view of its similar boundary structure. Based on the analysis, we propose a very simple geometric criterion to distinguish coupling from entanglement effects among two sets of degrees of freedom associated with each of the disconnected parts of the boundary.

  15. Self-dual warped AdS3 black holes

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Ning, Bo

    2010-12-01

    We study a new class of solutions of three-dimensional topological massive gravity. These solutions can be taken as nonextremal black holes, with their extremal counterparts being discrete quotients of spacelike warped AdS3 along the U(1)L isometry. We study the thermodynamics of these black holes and show that the first law is satisfied. We also show that for consistent boundary conditions, the asymptotic symmetry generators form only one copy of the Virasoro algebra with central charge cL=(4νℓ)/(G(ν2+3)), with which the Cardy formula reproduces the black hole entropy. We compute the real-time correlators of scalar perturbations and find a perfect match with the dual conformal field theory (CFT) predictions. Our study provides a novel example of warped AdS/CFT correspondence: the self-dual warped AdS3 black hole is dual to a CFT with nonvanishing left central charge. Moreover, our investigation suggests that the quantum topological massive gravity asymptotic to the same spacelike warped AdS3 in different consistent ways may be dual to different two-dimensional CFTs.

  16. CARE AND FEEDING OF FROGS

    SciTech Connect

    Pan, Margaret; Chiang, Eugene

    2012-01-15

    'Propellers' are features in Saturn's A ring associated with moonlets that open partial gaps. They exhibit non-Keplerian motion (Tiscareno et al.); the longitude residuals of the best-observed propeller, 'Bleriot', appear consistent with a sinusoid of period {approx}4 years. Pan and Chiang proposed that propeller moonlets librate in 'frog resonances' with co-orbiting ring material. By analogy with the restricted three-body problem, they treated the co-orbital material as stationary in the rotating frame and neglected non-co-orbital material. Here we use simple numerical experiments to extend the frog model, including feedback due to the gap's motion, and drag associated with the Lindblad disk torques that cause Type I migration. Because the moonlet creates the gap, we expect the gap centroid to track the moonlet, but only after a time delay t{sub delay}, the time for a ring particle to travel from conjunction with the moonlet to the end of the gap. We find that frog librations can persist only if t{sub delay} exceeds the frog libration period P{sub lib}, and if damping from Lindblad torques balances driving from co-orbital torques. If t{sub delay} << Pl{sub ib}, then the libration amplitude damps to zero. In the case of Bleriot, the frog resonance model can reproduce the observed libration period P{sub lib} {approx_equal} 4 yr. However, our simple feedback prescription suggests that Bleriot's t{sub delay} {approx} 0.01P{sub lib}, which is inconsistent with the observed libration amplitude of 260 km. We urge more accurate treatments of feedback to test the assumptions of our toy models.

  17. Secondary plasma formation after single pulse laser ablation underwater and its advantages for laser induced breakdown spectroscopy (LIBS).

    PubMed

    Gavrilović, M R; Cvejić, M; Lazic, V; Jovićević, S

    2016-06-01

    In this work we present studies of spatial and temporal plasma evolution after single pulse ablation of an aluminium target in water. The laser ablation was performed using 20 ns long pulses emitted at 1064 nm. The plasma characterization was performed by fast photography, the Schlieren technique, shadowgraphy and optical emission spectroscopy. The experimental results indicate the existence of two distinct plasma stages: the first stage has a duration of approximately 500 ns from the laser pulse, and is followed by a new plasma growth starting from the crater center. The secondary plasma slowly evolves inside the growing vapor bubble, and its optical emission lasts over several tens of microseconds. Later, the hot glowing particles, trapped inside the vapor cavity, were detected during the whole cycle of the bubble, where the first collapse occurs after 475 μs from the laser pulse. Differences in the plasma properties during the two evolution phases are discussed, with an accent on the optical emission since its detection is of primary importance for LIBS. Here we demonstrate that the LIBS signal quality in single pulse excitation underwater can be greatly enhanced by detecting only the secondary plasma emission, and also by applying long acquisition gates (in the order of 10-100 μs). The presented results are of great importance for LIBS measurements inside a liquid environment, since they prove that a good analytical signal can be obtained by using nanosecond pulses from a single commercial laser source and by employing cost effective, not gated detectors. PMID:27180875

  18. Trace detection of light elements by laser-induced breakdown spectroscopy (LIBS): Applications to non-conducting materials

    NASA Astrophysics Data System (ADS)

    Khater, Mohamed A.

    2013-10-01

    The existence as well as concentration of light (low-atomic number) elements is directly related to some of the most important properties of almost all materials. Thus, the development of a direct, fast, and sensitive spectroscopic method for the analytical quantification of these elements is considered an important continuing challenge in many fields. In this report, results obtained from previous as well as most recent studies regarding trace detection of light elements in non-conducting materials by laser-induced breakdown spectroscopy (LIBS) technique are reviewed for the first time. Firstly, we introduce investigations performed in the far- and vacuum-UV as well as UV-visible-NIR spectral domains, and cover many non-conducting materials including gases, aerosols, soil, cement, and selected organic compounds. The report also demonstrates important analytical results for the elements lithium, beryllium, boron, carbon, fluorine, phosphorus, sulfur, and chlorine. In addition, key characterization information relating to a specific element in a given matrix and state is summarized in such a way that relevant resources can easily be traced. Furthermore, in order to facilitate tracking down the evolution of the technique for a particular material category, a chronological order has been devised. In the second part of the review, the latest developments and advances in instrumentation and methodologies of the LIBS technique, particularly in the realm of light elements detection, are discussed. The sensitive detection of light elements in the UV-VIS-NIR is still unsatisfactory, and more work is needed in order to achieve better analytical performance in terms of precision, accuracy and limits of detection. The author anticipates that significant sensitivity improvements should be realized by combining LIBS, employing femtosecond laser pulses, with other diagnostic techniques based on probing the plasma via diode lasers.

  19. libNeuroML and PyLEMS: using Python to combine procedural and declarative modeling approaches in computational neuroscience

    PubMed Central

    Vella, Michael; Cannon, Robert C.; Crook, Sharon; Davison, Andrew P.; Ganapathy, Gautham; Robinson, Hugh P. C.; Silver, R. Angus; Gleeson, Padraig

    2014-01-01

    NeuroML is an XML-based model description language, which provides a powerful common data format for defining and exchanging models of neurons and neuronal networks. In the latest version of NeuroML, the structure and behavior of ion channel, synapse, cell, and network model descriptions are based on underlying definitions provided in LEMS, a domain-independent language for expressing hierarchical mathematical models of physical entities. While declarative approaches for describing models have led to greater exchange of model elements among software tools in computational neuroscience, a frequent criticism of XML-based languages is that they are difficult to work with directly. Here we describe two Application Programming Interfaces (APIs) written in Python (http://www.python.org), which simplify the process of developing and modifying models expressed in NeuroML and LEMS. The libNeuroML API provides a Python object model with a direct mapping to all NeuroML concepts defined by the NeuroML Schema, which facilitates reading and writing the XML equivalents. In addition, it offers a memory-efficient, array-based internal representation, which is useful for handling large-scale connectomics data. The libNeuroML API also includes support for performing common operations that are required when working with NeuroML documents. Access to the LEMS data model is provided by the PyLEMS API, which provides a Python implementation of the LEMS language, including the ability to simulate most models expressed in LEMS. Together, libNeuroML and PyLEMS provide a comprehensive solution for interacting with NeuroML models in a Python environment. PMID:24795618

  20. libNeuroML and PyLEMS: using Python to combine procedural and declarative modeling approaches in computational neuroscience.

    PubMed

    Vella, Michael; Cannon, Robert C; Crook, Sharon; Davison, Andrew P; Ganapathy, Gautham; Robinson, Hugh P C; Silver, R Angus; Gleeson, Padraig

    2014-01-01

    NeuroML is an XML-based model description language, which provides a powerful common data format for defining and exchanging models of neurons and neuronal networks. In the latest version of NeuroML, the structure and behavior of ion channel, synapse, cell, and network model descriptions are based on underlying definitions provided in LEMS, a domain-independent language for expressing hierarchical mathematical models of physical entities. While declarative approaches for describing models have led to greater exchange of model elements among software tools in computational neuroscience, a frequent criticism of XML-based languages is that they are difficult to work with directly. Here we describe two Application Programming Interfaces (APIs) written in Python (http://www.python.org), which simplify the process of developing and modifying models expressed in NeuroML and LEMS. The libNeuroML API provides a Python object model with a direct mapping to all NeuroML concepts defined by the NeuroML Schema, which facilitates reading and writing the XML equivalents. In addition, it offers a memory-efficient, array-based internal representation, which is useful for handling large-scale connectomics data. The libNeuroML API also includes support for performing common operations that are required when working with NeuroML documents. Access to the LEMS data model is provided by the PyLEMS API, which provides a Python implementation of the LEMS language, including the ability to simulate most models expressed in LEMS. Together, libNeuroML and PyLEMS provide a comprehensive solution for interacting with NeuroML models in a Python environment. PMID:24795618

  1. LIB spectroscopic and biochemical analysis to characterize lead toxicity alleviative nature of silicon in wheat (Triticum aestivum L.) seedlings.

    PubMed

    Tripathi, Durgesh Kumar; Singh, Vijay Pratap; Prasad, Sheo Mohan; Dubey, Nawal Kishore; Chauhan, Devendra Kumar; Rai, Awadesh Kumar

    2016-01-01

    The responses of wheat seedling treated with silicon (Si; 10 μM) and lead (Pb; 100 μM) for 7 days have been investigated by analyzing growth, Pb uptake, chlorophyll fluorescence, oxidative stress, antioxidants and nutrients regulation. Results indicated that, Pb significantly (P<0.05) declined growth of seedlings which was accompanied by uptake of Pb. Under Pb stress, fluorescence parameters: Fv/Fm ratio and qP were significantly (P<0.05) decreased while NPQ was increased. Si addition alleviated Pb-induced decrease in growth and alterations in photosynthesis, and also significantly (P<0.05) lowered Pb uptake. Under Pb treatment, oxidative stress markers: hydrogen peroxide and lipid peroxidation were enhanced while DPPH(•) scavenging capacity and total phenolic compounds (TPCs) were decreased significantly, however, Si addition improved the status of antioxidants. The non-protein thiols (NP-SH) showed enhanced level under Pb stress. Pb stress considerably disturbed status of the nutrients as decrease in Ca, P, Mg, Zn and Ni contents while an increase in K, S, B, Cu, Fe, Mn and Na contents were noticed. Si addition maintained status of all the nutrients remarkably. The quickest method of element analysis: LIBS spectra revealed significantly lower uptake of Pb in seedlings grown under Si and Pb combination and same was correlated with the data of AAS. Overall results pointed out that excess Pb uptake disturbed status of nutrients, photosynthetic performance, antioxidant capacity, hence severe oxidative damage to lipids occurred. Further, Si supplementation successfully regulated these parameters by inhibiting Pb uptake hence maintained growth of wheat seedlings. Similar pattern of data recorded by the LIBS, AAS and ICAP-AES confirmed that LIBS may be one of the promising and authentic tools to monitor the mineral and metal distribution in the plants without hampering or disturbing the environment due to its eco-friendly and non-invasive nature. PMID:26700425

  2. Nonlinear mapping technique for data visualization and clustering assessment of LIBS data: application to ChemCam data.

    PubMed

    Lasue, J; Wiens, R C; Stepinski, T F; Forni, O; Clegg, S M; Maurice, S

    2011-07-01

    ChemCam is a remote laser-induced breakdown spectroscopy (LIBS) instrument that will arrive on Mars in 2012, on-board the Mars Science Laboratory Rover. The LIBS technique is crucial to accurately identify samples and quantify elemental abundances at various distances from the rover. In this study, we compare different linear and nonlinear multivariate techniques to visualize and discriminate clusters in two dimensions (2D) from the data obtained with ChemCam. We have used principal components analysis (PCA) and independent components analysis (ICA) for the linear tools and compared them with the nonlinear Sammon's map projection technique. We demonstrate that the Sammon's map gives the best 2D representation of the data set, with optimization values from 2.8% to 4.3% (0% is a perfect representation), together with an entropy value of 0.81 for the purity of the clustering analysis. The linear 2D projections result in three (ICA) and five times (PCA) more stress, and their clustering purity is more than twice higher with entropy values about 1.8. We show that the Sammon's map algorithm is faster and gives a slightly better representation of the data set if the initial conditions are taken from the ICA projection rather than the PCA projection. We conclude that the nonlinear Sammon's map projection is the best technique for combining data visualization and clustering assessment of the ChemCam LIBS data in 2D. PCA and ICA projections on more dimensions would improve on these numbers at the cost of the intuitive interpretation of the 2D projection by a human operator. PMID:21331488

  3. Daily feeding regimen impacts pig growth and behavior.

    PubMed

    Colpoys, Jessica D; Johnson, Anna K; Gabler, Nicholas K

    2016-05-15

    A primary swine production goal is to increase efficiency of lean tissue gains. While many swine production systems currently utilize ad libitum feeding, recent research suggests that altering feeding patterns may impact feed efficiency. Therefore, the objective of this study was to compare two feeding patterns and evaluate their impact on whole body tissue accretion, feeding behavior and activity in growing pigs. Forty eight individually housed gilts (55.9±5.2kg on test BW) were assigned into one of two feeding treatments: 1) Free access to the feeder (Free Access) or 2) twice daily access where gilts were allowed to eat ad libitum between 08:00-09:00h and again from 17:00-18:00h (2×). Pig performance was recorded weekly for 55days and average daily gain (ADG), average daily feed intake (ADFI), and gain:feed (G:F) was calculated. Body composition was assessed in 12 gilts per treatment using dual X-ray absorptiometry (DXA) at day -3 and 55 of treatment, and tissue accretion rates were calculated. Gilt behaviors were assessed via video analysis during week 7 and included time spent eating, feeding rate, enrichment interaction, postural changes, standing, sitting, and lying behaviors. Gilts fed 2× had lower ADG and ADFI compared to Free Access gilts (P≤0.01); however, no treatment difference in G:F was observed (P=0.83). At day 55 gilts fed 2× had a lower fat:protein compared to Free Access gilts (P=0.05). Fat, lean, and protein accretion rates were lower in gilts fed 2× compared to those fed Free Access (P=0.01). Gilts fed 2× ate less frequently and for a shorter duration of time, interacted with enrichment more frequently (P≤0.005), and tended to have less frequent postural changes compared to Free Access gilts (P=0.08). No treatment differences were observed in duration of time spent standing, sitting, or lying (P≥0.39). Although feed regimen did not alter feed efficiency, these data indicate that twice daily feeding reduced gilt adiposity and growth

  4. A large depth of field LIBS measuring system for elemental analysis of moving samples of raw coal

    NASA Astrophysics Data System (ADS)

    Redoglio, D.; Golinelli, E.; Musazzi, S.; Perini, U.; Barberis, F.

    2016-02-01

    We present preliminary results of laboratory tests carried out on moving samples of coal by means of an innovative LIBS system with a large depth of field. The measuring system has been conceived to operate on line in a coal fired power plant. To duplicate at laboratory level the real situation, the coal samples are sequentially positioned under the measuring head by means of a translation/rotation unit that allows reproducing the behavior of the raw coal transported by a conveyor belt. Experimental results show that both carbon and hydrogen concentration as well as the content of some inorganic components (Al, Ca, Fe, Si) can be evaluated with good accuracy.

  5. Heavy metal concentrations in soils as determined by laser-induced breakdown spectroscopy (LIBS), with special emphasis on chromium.

    PubMed

    Senesi, G S; Dell'Aglio, M; Gaudiuso, R; De Giacomo, A; Zaccone, C; De Pascale, O; Miano, T M; Capitelli, M

    2009-05-01

    Soil is unanimously considered as one of the most important sink of heavy metals released by human activities. Heavy metal analysis of natural and polluted soils is generally conducted by the use of atomic absorption spectroscopy (AAS) or inductively coupled plasma optical emission spectroscopy (ICP-OES) on adequately obtained soil extracts. Although in recent years the emergent technique of laser-induced breakdown spectroscopy (LIBS) has been applied widely and with increasing success for the qualitative and quantitative analyses of a number of heavy metals in soil matrices with relevant simplification of the conventional methodologies, the technique still requires further confirmation before it can be applied fully successfully in soil analyses. The main objective of this work was to demonstrate that new developments in LIBS technique are able to provide reliable qualitative and quantitative analytical evaluation of several heavy metals in soils, with special focus on the element chromium (Cr), and with reference to the concentrations measured by conventional ICP spectroscopy. The preliminary qualitative LIBS analysis of five soil samples and one sewage sludge sample has allowed the detection of a number of elements including Al, Ca, Cr, Cu, Fe, Mg, Mn, Pb, Si, Ti, V and Zn. Of these, a quantitative analysis was also possible for the elements Cr, Cu, Pb, V and Zn based on the obtained linearity of the calibration curves constructed for each heavy metal, i.e., the proportionality between the intensity of the LIBS emission peaks and the concentration of each heavy metal in the sample measured by ICP. In particular, a triplet of emission lines for Cr could be used for its quantitative measurement. The consistency of experiments made on various samples was supported by the same characteristics of the laser-induced plasma (LIP), i.e., the typical linear distribution confirming the existence of local thermodynamic equilibrium (LTE) condition, and similar excitation

  6. Molecular dynamics (MD) study on the electrochemical properties of electrolytes in lithium-ion battery (LIB) applications

    NASA Astrophysics Data System (ADS)

    Salami, Negin

    While the high energy density and the power along with longer cycle life and less requirements of maintenance distinguish the rechargeable lithium-ion batteries (LIBs) from other energy storage devices, development of an electrolyte of LIBs with optimized properties still constitutes a challenge towards next-generation LIB systems with robust electrochemical performance. The electrolytes serve as the medium to provide ionic conduction path between the electrodes as their basic function. Conductivity of the solutions are mainly affected by their transport properties and the electrolyte electrode/separator interfacial phenomena. Although many contributions on thermodynamic properties of the electrolytes consist of alkyl carbonates mixed with salts have been previously studied, relatively little information is known regarding the correlation between interfacial properties of the electrolyte -electrode/separator with electrochemical properties of the cell. In this study, therefore, we present the impacts of salt concentration and temperature-dependent properties of LIBs on wetting behavior of various electrolytes, i.e., ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and propylene carbonate (PC), in contact with the graphite anode and polyethylene (PE)/polypropylene (PP) separator using molecular dynamics (MD) computational technique. The results based on MD computations affirm the general consistent dependency of interfacial tension energies to polarity of the solvents in DEC, EMC, and PC electrolytes contained 1 M LiPF6 salt. The PC systems interestingly showed inverse trend due to the special stacking motifs of PC layers that may increase the interfacial electrostatic interactions. Temperature did not show significant effect on the interfacial energies of linear solvents whereas PC exhibited more tendency to interact with the graphite anode at T = 25 C compared to the similar solution at 0 C. Moreover, the electrolytes that incorporated same solvents had

  7. Heavy metal concentrations in soils as determined by laser-induced breakdown spectroscopy (LIBS), with special emphasis on chromium

    SciTech Connect

    Senesi, G.S.; De Giacomo, A.; Zaccone, C.

    2009-05-15

    Soil is unanimously considered as one of the most important sink of heavy metals released by human activities. Heavy metal analysis of natural and polluted soils is generally conducted by the use of atomic absorption spectroscopy (AAS) or inductively coupled plasma optical emission spectroscopy (ICP-OES) on adequately obtained soil extracts. Although in recent years the emergent technique of laser-induced breakdown spectroscopy (LIBS) has been applied widely and with increasing success for the qualitative and quantitative analyses of a number of heavy metals in soil matrices with relevant simplification of the conventional methodologies, the technique still requires further confirmation before it can be applied fully successfully in soil analyses. The main objective of this work was to demonstrate that new developments in LIBS technique are able to provide reliable qualitative and quantitative analytical evaluation of several heavy metals in soils, with special focus on the element chromium (Cr), and with reference to the concentrations measured by conventional ICP spectroscopy. The preliminary qualitative LIBS analysis of five soil samples and one sewage sludge sample has allowed the detection of a number of elements including Al, Ca, Cr, Cu, Fe, Mg, Mn, Pb, Si, Ti, V and Zn. Of these, a quantitative analysis was also possible for the elements Cr, Cu, Pb, V and Zn based on the obtained linearity of the calibration curves constructed for each heavy metal, i.e., the proportionality between the intensity of the LIBS emission peaks and the concentration of each heavy metal in the sample measured by ICP. In particular, a triplet of emission lines for Cr could be used for its quantitative measurement. The consistency of experiments made on various samples was supported by the same characteristics of the laser-induced plasma (LIP), i.e., the typical linear distribution confirming the existence of local thermodynamic equilibrium (LTE) condition, and similar excitation

  8. Relationship Between LIBS Ablation and Pit Volume for Geologic Samples: Applications for the In Situ Absolute Geochronology

    NASA Technical Reports Server (NTRS)

    Devismes, Damien; Cohen, Barbara; Miller, J.-S.; Gillot, P.-Y.; Lefevre, J.-C.; Boukari, C.

    2014-01-01

    These first results demonstrate that LIBS spectra can be an interesting tool to estimate the ablated volume. When the ablated volume is bigger than 9.10(exp 6) cubic micrometers, this method has less than 10% of uncertainties. Far enough to be directly implemented in the KArLE experiment protocol. Nevertheless, depending on the samples and their mean grain size, the difficulty to have homogeneous spectra will increase with the ablated volume. Several K-Ar dating studies based on this approach will be implemented. After that, the results will be shown and discussed.

  9. Warped AdS3/dipole-CFT duality

    NASA Astrophysics Data System (ADS)

    Song, Wei; Strominger, Andrew

    2012-05-01

    String theory contains solutions with {{SL}}( {{2},{R}} ){{R}} × {{U}}{( {1} )_L} -invariant warped AdS3 (WAdS3) factors arising as continuous deformations of ordinary AdS3 factors. We propose that some of these are holographically dual to the IR limits of nonlocal dipole-deformed 2D D-brane gauge theories, referred to as "dipole CFTs". Neither the bulk nor boundary theories are currently well-understood, and consequences of the proposed duality for both sides is investigated. The bulk entropy-area law suggests that dipole CFTs have (at large N) a high-energy density of states which does not depend on the deformation parameter. Putting the boundary theory on a spatial circle leads to closed timelike curves in the bulk, suggesting a relation of the latter to dipole-type nonlocality.

  10. New boundary conditions for AdS3

    NASA Astrophysics Data System (ADS)

    Compère, Geoffrey; Song, Wei; Strominger, Andrew

    2013-05-01

    New chiral boundary conditions are found for quantum gravity with matter on AdS3. The associated asymptotic symmetry group is generated by a single right-moving U(1) Kac-Moody-Virasoro algebra with {c_R}={3ℓ}/2G . The Kac-Moody zero mode generates global left-moving translations and equals, for a BTZ black hole, the sum of the total mass and spin. The level is positive about the global vacuum and negative in the black hole sector, corresponding to ergosphere formation. Realizations arising in Chern-Simons gravity and string theory are analyzed. The new boundary conditions are shown to naturally arise for warped AdS3 in the limit that the warp parameter is taken to zero.

  11. Observing quantum gravity in asymptotically AdS space

    NASA Astrophysics Data System (ADS)

    Emelyanov, Slava

    2015-12-01

    The question is studied of whether an observer can discover quantum gravity in the semiclassical regime. It is shown that it is indeed possible to probe a certain quantum gravity effect by employing an appropriately designed detector. The effect is related to the possibility of having topologically inequivalent geometries in the path-integral approach at the same time. A conformal field theory (CFT) state which is expected to describe the eternal anti-de Sitter (AdS) black hole in the large-N limit is discussed. It is argued under certain assumptions that the black hole boundary should be merely a patch of the entire AdS boundary. This leads then to a conclusion that that CFT state is the ordinary CFT vacuum restricted to that patch. If existent, the bulk CFT operators can behave as the ordinary semiclassical quantum field theory in the large-N limit in the weak sense.

  12. Semiclassical Virasoro blocks from AdS3 gravity

    NASA Astrophysics Data System (ADS)

    Hijano, Eliot; Kraus, Per; Perlmutter, Eric; Snively, River

    2015-12-01

    We present a unified framework for the holographic computation of Virasoro conformal blocks at large central charge. In particular, we provide bulk constructions that correctly reproduce all semiclassical Virasoro blocks that are known explicitly from conformal field theory computations. The results revolve around the use of geodesic Witten diagrams, recently introduced in [1], evaluated in locally AdS3 geometries generated by backreaction of heavy operators. We also provide an alternative computation of the heavy-light semiclassical block — in which two external operators become parametrically heavy — as a certain scattering process involving higher spin gauge fields in AdS3; this approach highlights the chiral nature of Virasoro blocks. These techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.

  13. Feeding gastrostomy. Assistant or assassin?

    PubMed

    Burtch, G D; Shatney, C H

    1985-04-01

    Following several deaths from pulmonary aspiration in severely ill or chronically debilitated patients receiving nasogastric tube feedings, a study was undertaken to determine the incidence of aspiration pneumonitis in patients with feeding gastrostomies. During a 15-month interval, 22 feeding gastrostomies and nine feeding jejunostomies were performed. In the former group, eight patients experienced aspiration pneumonitis, with two deaths. Six patients with Stamm gastrostomies and two patients with permanent mucosal-lined gastrostomies experienced pulmonary aspiration. In contrast, aspiration pneumonia did not occur in our small series of patients with feeding jejunostomies. The high incidence of pulmonary aspiration in patients with feeding gastrostomies strongly suggests that, for chronic enteral nutrition in patients who are unable to protect their airway, a feeding jejunostomy is preferable to a feeding gastrostomy. PMID:3920939

  14. Alday-Maldacena Duality and AdS Plateau Problem

    NASA Astrophysics Data System (ADS)

    Morozov, A.

    A short summary of approximate approach to the study of minimal surfaces in AdS, based on solving Nambu-Goto equations iteratively. Today, after partial denunciation of the BDS conjecture, this looks like the only constructive approach to understanding the ways of its possible modification and thus to saving the Alday-Maldacena duality. Numerous open technical problems are explicitly formulated throughout the text.

  15. On information loss in AdS3/CFT2

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, A. Liam; Kaplan, Jared; Li, Daliang; Wang, Junpu

    2016-05-01

    We discuss information loss from black hole physics in AdS3, focusing on two sharp signatures infecting CFT2 correlators at large central charge c: `forbidden singularities' arising from Euclidean-time periodicity due to the effective Hawking temperature, and late-time exponential decay in the Lorentzian region. We study an infinite class of examples where forbidden singularities can be resolved by non-perturbative effects at finite c, and we show that the resolution has certain universal features that also apply in the general case. Analytically continuing to the Lorentzian regime, we find that the non-perturbative effects that resolve forbidden singularities qualitatively change the behavior of correlators at times t ˜ S BH , the black hole entropy. This may resolve the exponential decay of correlators at late times in black hole backgrounds. By Borel resumming the 1 /c expansion of exact examples, we explicitly identify `information-restoring' effects from heavy states that should correspond to classical solutions in AdS3. Our results suggest a line of inquiry towards a more precise formulation of the gravitational path integral in AdS3.

  16. Supersymmetric giant graviton solutions in AdS3

    NASA Astrophysics Data System (ADS)

    Mandal, Gautam; Raju, Suvrat; Smedbäck, Mikael

    2008-02-01

    We parametrize all classical probe brane configurations that preserve four supersymmetries in (a) the extremal D1-D5 geometry, (b) the extremal D1-D5-P geometry, (c) the smooth D1-D5 solutions proposed by Lunin and Mathur, and (d) global AdS3×S3×T4/K3. These configurations consist of D1 branes, D5 branes, and bound states of D5 and D1 branes with the property that a particular Killing vector is tangent to the brane world volume at each point. We show that the supersymmetric sector of the D5-brane world volume theory may be analyzed in an effective 1+1 dimensional framework that places it on the same footing as D1 branes. In global AdS and the corresponding Lunin-Mathur solution, the solutions we describe are “bound” to the center of AdS for generic parameters and cannot escape to infinity. We show that these probes only exist on the submanifold of moduli space where the background BNS field and theta angle vanish. We quantize these probes in the near-horizon region of the extremal D1-D5 geometry and obtain the theory of long strings discussed by Seiberg and Witten.

  17. An overview: biomolecules from microalgae for animal feed and aquaculture.

    PubMed

    Yaakob, Zahira; Ali, Ehsan; Zainal, Afifi; Mohamad, Masita; Takriff, Mohd Sobri

    2014-12-01

    Despite being more popular for biofuel, microalgae have gained a lot of attention as a source of biomolecules and biomass for feed purposes. Algae farming can be established using land as well as sea and strategies can be designed in order to gain the products of specific interest in the optimal way. A general overview of the contributions of Algae to meet the requirements of nutrients in animal/aquaculture feed is presented in this study. In addition to its applications in animal/aquaculture feed, algae can produce a number of biomolecules including astaxanthin, lutein, beta-carotene, chlorophyll, phycobiliprotein, Polyunsaturated Fatty Acids (PUFAs), beta-1,3-glucan, and pharmaceutical and nutraceutical compounds which have been reviewed with respect to their commercial importance and current status. The review is further extended to highlight the adequate utilization of value added products in the feeds for livestock, poultry and aquaculture (with emphasis in shrimp farming). PMID:25984489

  18. Dual wire weld feed proportioner

    NASA Technical Reports Server (NTRS)

    Nugent, R. E.

    1968-01-01

    Dual feed mechanism enables proportioning of two different weld feed wires during automated TIG welding to produce a weld alloy deposit of the desired composition. The wires are fed into the weld simultaneously. The relative feed rates of the wires and the wire diameters determine the weld deposit composition.

  19. Preliminary study on detection sediment contamination in soil affected by the Indian Ocean giant tsunami 2004 in Aceh, Indonesia using laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Idris, Nasrullah; Ramli, Muliadi; Hedwig, Rinda; Lie, Zener Sukra; Kurniawan, Koo Hendrik

    2016-03-01

    This work is intended to asses the capability of LIBS for the detection of the tsunami sediment contamination in soil. LIBS apparatus used in this work consist of a laser system and an optical multichannel analyzer (OMA) system. The soil sample was collected from in Banda Aceh City, Aceh, Indonesia, the most affected region by the giant Indian Ocean tsunami 2004. The laser beam was focused onto surface of the soil pellet using a focusing lens to produce luminous plasma. The experiment was conducted under air as surrounding gas at 1 atmosphere. The emission spectral lines from the plasma were detected by the OMA system. It was found that metal including heavy metals can surely be detected, thus implying the potent of LIBS technique as a fast screening tools of tsunami sediment contamination.

  20. Effect of tanniferous leaf meal based multi-nutrient blocks on feed intake, hematological profile, immune response, and body weight changes in Haemonchus contortus infected goats

    PubMed Central

    Singh, Surender; Pathak, A. K.; Sharma, R. K.; Khan, Muzaffer

    2015-01-01

    Aim: The aim was to assess the effect of multi nutrient block (MNB) supplementation with and without tanniferous leaf meal mixture on feed intake, hematological profile, immune response, and body weight changes of goats that were experimentally infected with Haemonchus contortus. Materials and Methods: Total 12 adult male goats of similar age and body weight (26.49±0.87) were allocated in 3 groups in completely randomized design. MNB supplemented in first two groups i.e. in T1 (no infection) and T2 (H. contortus infection @ 1500 L3/goat) group, while, MNB-condensed tannin (CT) supplemented in T3 (H. contortus infection @ 1500 L3/goat + CT source). All goats were fed concentrate mixture @ 100 g/day/goat, ad lib wheat straw and MNB or MNB-CT to meet their requirement for maintenance. Body weights were recorded and blood and fecal samples were collected at 0 day and thereafter at 15 days intervals for a period of 75 days for the assessment of body weight changes, hematological profile and H. contortus loads. Both humoral and cell-mediated immune (CMI) response were assessed at the end of feeding trial. Results: Mean hemoglobin and packed cell volume (PCV) levels were found to be highest (p<0.001, p<0.05) in T1 group followed by T3 group and lowest values were observed in T2 group. However, The PCV values between T1 and T3 groups were found to be statistically non-significant (p<0.05). The humoral and CMI response were significantly (p<0.036) higher in T3 group as compared to T2 group. MNB-CT supplementation significantly (p<0.001) reduced fecal egg counts in T3 group as compared to MNB supplemented T2 group. Conclusion: Supplementation of MNB-CT could be used as an alternative sustainable method to control H. contortus and maintained health status and performance of goats in face of parasitic challenge. PMID:27047137

  1. Bending AdS waves with new massive gravity

    NASA Astrophysics Data System (ADS)

    Ayón-Beato, Eloy; Giribet, Gaston; Hassaïne, Mokhtar

    2009-05-01

    We study AdS-waves in the three-dimensional new theory of massive gravity recently proposed by Bergshoeff, Hohm, and Townsend. The general configuration of this type is derived and shown to exhibit different branches, with different asymptotic behaviors. In particular, for the special fine tuning m2 = ±1/(2l2), solutions with logarithmic fall-off arise, while in the range m2 > -1/(2l2), spacetimes with Schrödinger isometry group are admitted as solutions. Spacetimes that are asymptotically AdS3, both for the Brown-Henneaux and for the weakened boundary conditions, are also identified. The metric function that characterizes the profile of the AdS-wave behaves as a massive excitation on the spacetime, with an effective mass given by meff2 = m2-1/(2l2). For the critical value m2 = -1/(2l2), the value of the effective mass precisely saturates the Breitenlohner-Freedman bound for the AdS3 space where the wave is propagating on. The analogies with the AdS-wave solutions of topologically massive gravity are also discussed. Besides, we consider the coupling of both massive deformations to Einstein gravity and find the exact configurations for the complete theory, discussing all the different branches exhaustively. One of the effects of introducing the Chern-Simons gravitational term is that of breaking the degeneracy in the effective mass of the generic modes of pure New Massive Gravity, producing a fine structure due to parity violation. Another effect is that the zoo of exact logarithmic specimens becomes considerably enlarged.

  2. ADS/CFT and QCD

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.; /Costa Rica U. /SLAC

    2007-02-21

    The AdS/CFT correspondence between string theory in AdS space and conformal .eld theories in physical spacetime leads to an analytic, semi-classical model for strongly-coupled QCD which has scale invariance and dimensional counting at short distances and color confinement at large distances. Although QCD is not conformally invariant, one can nevertheless use the mathematical representation of the conformal group in five-dimensional anti-de Sitter space to construct a first approximation to the theory. The AdS/CFT correspondence also provides insights into the inherently non-perturbative aspects of QCD, such as the orbital and radial spectra of hadrons and the form of hadronic wavefunctions. In particular, we show that there is an exact correspondence between the fifth-dimensional coordinate of AdS space z and a specific impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron in ordinary space-time. This connection allows one to compute the analytic form of the frame-independent light-front wavefunctions, the fundamental entities which encode hadron properties and allow the computation of decay constants, form factors, and other exclusive scattering amplitudes. New relativistic lightfront equations in ordinary space-time are found which reproduce the results obtained using the 5-dimensional theory. The effective light-front equations possess remarkable algebraic structures and integrability properties. Since they are complete and orthonormal, the AdS/CFT model wavefunctions can also be used as a basis for the diagonalization of the full light-front QCD Hamiltonian, thus systematically improving the AdS/CFT approximation.

  3. Acute phase proteins response to feed deprivation in broiler chickens.

    PubMed

    Najafi, P; Zulkifli, I; Soleimani, A F; Goh, Y M

    2016-04-01

    Feed deprivation in poultry farming imposes some degree of stress to the birds, and adversely affects their well -being. Serum levels of acute phase proteins (APP) are potential physiological indicators of stress attributed to feed deprivation. However, it has not been determined how long it takes for a measurable APP response to stressors to occur in avian species. An experiment was designed to delineate the APP and circulating levels of corticosterone responses in commercial broiler chickens to feed deprivation for 30 h. It was hypothesized that feed deprivation would elicit both APP and corticosterone (CORT) reactions within 30 h that is probably associated with stress of hunger. Twenty-one day old birds were subjected to one of 5 feed deprivation periods: 0 (ad libitum, AL), 6, 12, 18, 24, and 30 h. Upon completion of the deprivation period, blood samples were collected to determine serum CORT, ovotransferrin (OVT), α1-acid glycoprotein (AGP), and ceruloplasmin (CP) concentrations. Results showed that feed deprivation for 24 h or more caused a marked elevation in CORT (P=0.002 and P<0.0001, respectively) when compared to AL. However, increases in AGP (P=0.0005), CP (P=0.0002), and OVT (P=0.0003) were only noted following 30 h of feed deprivation. It is concluded that elicitation of AGP, CP, and OVT response may represent a more chronic stressful condition than CORT response in assessing the well-being of broiler chickens. PMID:26908886

  4. Breast-feeding, the better option: getting the message across.

    PubMed

    Rossiter, J C

    1993-01-01

    Most Vietnamese women breast feed their children, but when Vietnamese women migrate to Western countries, most bottle-feed their children or wean their children very early. Breast feeding among Vietnamese immigrants in Sydney, Australia, is being encouraged with the help of a 25-minute, culture specific educational videotape. This videotape provides information on the benefits of breast feeding, offers advice on infant-feeding practices and uses an entertaining style to convey its messages. To develop the videotape, 87 Vietnamese women living in Sydney participated in a survey on infant-feeding practices. It was clear that the videotape should be produced in Vietnamese. It took 3 months to write the script, obtain a grant, and select actors. The videotape tells the story of a young Vietnamese mother-to-be who talks with her doctors and friends and decides to breast feed her baby. the filming lasted 4 weeks, and editing took an additional 2 weeks. After preliminary screenings among pregnant Vietnamese women an health workers, English sub titles were added. The videotape is available from the University of Western Sydney, Nepean, and has been distributed to hospitals. It was produced at a relatively low cost and presents its health information in a culture-and language-specific format which is also enjoyable for the viewers. PMID:8397750

  5. Quantitative Analysis of Composition Change in AZ31 Magnesium Alloy Using CF-LIBS After Laser Material Processing

    NASA Astrophysics Data System (ADS)

    Zhu, Dehua; Cao, Yu; Zhong, Rong; Chen, Xiaojing

    2015-11-01

    The concentration of elements in molten metal of AZ31 magnesium alloy after long pulsed Nd:YAG laser processing was quantitatively analyzed by using calibration-free laser-induced breakdown spectroscopy (CF-LIBS). The composition change in AZ31 magnesium alloy under different laser pulse width was also investigated. The experimental results showed that CF-LIBS can obtain satisfactory quantitative or semi-quantitative results for matrix or major elements, while only qualitative analysis was possible for minor or trace elements. Moreover, it is found that the chemical composition of molten metal will change after laser processing. The concentration of magnesium in molten metal is lower than that present in the base metal. The Mg loss increases with an increase of pulse width in the laser processing. This result shows that the selective vaporization of different elements is affected by the pulse width during laser processing. supported by National Natural Science Foundation of China (Nos. 61405147, 51375348) and the Scientific Research Fund of Zhejiang Provincial Education Department, China (No. Y201430387)

  6. Classification of vegetable oils based on their concentration of saturated fatty acids using laser induced breakdown spectroscopy (LIBS).

    PubMed

    Mbesse Kongbonga, Yvon G; Ghalila, Hassen; Onana, Marthe Boyomo; Ben Lakhdar, Zohra

    2014-03-15

    Spectrochemical analyses of organic liquid media such as vegetable oils and sweetened water were performed with the use of LIBS. The aim of this work is to study, on the basis of spectral analyses by LIBS technique of "Swan band" of C2 emitted by different vegetable oils in liquid phase, the characteristics of each organic media. Furthermore this paper proposes, as a classification, a single parameter that could be used to determine the concentration of saturated fatty acids of vegetable oils. A Nd:YAG operating at λ=532 nm and an energies per pulse of 30 mJ was focused onto the surface of the liquid in ambient air. Following ablation of vegetable oils and sweetened water, we find that vibrational bonds of C2 were released from the molecule containing carbon-carbon bonds linear. In the case of vegetable oils, we find a clear relationship between C2 emission from the plasma and the concentration of saturated fatty acids in the oil. PMID:24206726

  7. Detection of calculus by laser-induced breakdown spectroscopy (LIBS) using an ultra-short pulse laser system (USPL)

    NASA Astrophysics Data System (ADS)

    Schelle, F.; Brede, O.; Krueger, S.; Oehme, B.; Dehn, C.; Frentzen, M.; Braun, A.

    2011-03-01

    The aim of this study was to assess the detection of calculus by Laser Induced Breakdown Spectroscopy (LIBS). The study was performed with an Nd:YVO4 laser, emitting pulses with a duration of 8 ps at a wavelength of 1064 nm. A repetition rate of 500 kHz at an average power of 5 W was used. Employing a focusing lense, intensities of the order of 1011 W/cm2 were reached on the tooth surface. These high intensities led to the generation of a plasma. The light emitted by the plasma was collimated into a fibre and then analyzed by an echelle spectroscope in the wavelength region from 220 nm - 900 nm. A total number of 15 freshly extracted teeth was used for this study. For each tooth the spectra of calculus and cementum were assessed separately. Comprising all single measurements median values were calculated for the whole spectrum, leading to two specific spectra, one for calculus and one for cementum. For further statistical analysis 28 areas of interest were defined as wavelength regions, in which the signal strength differed regarding the material. In 7 areas the intensity of the calculus spectrum differed statistically significant from the intensity of the cementum spectrum (p < 0.05). Thus it can be concluded that Laser Induced Breakdown Spectroscopy is well suited as method for a reliable diagnostic of calculus. Further studies are necessary to verify that LIBS is a minimally invasive method allowing a safe application in laser-guided dentistry.

  8. Investigation of Growth Patterns due to Environmental Factors on the Surface of Bivalve shells with LIBS and Raman Spectroscopy

    NASA Astrophysics Data System (ADS)

    Palmer, Andria; Mays, Joseph; Amos, James; Dynka, Tom; Ujj, Laszlo

    Environmental disturbances (such as temperature or chemical disturbances) can cause bivalve mollusk shells to grow faster or slower and cause changes in color and surface ring pattern. We have selected a few shells from our local habitat in Pensacola Beach, FL to analyze without sample treatment to determine what factors may have come into play during growth and use this as a way to analyze our marine environment. Laser Induced Breakdown Spectroscopy (LIBS) uses high energy laser pulses (355 and 532nm) to ablate the sample and create a micro-plasma from which emission spectra can be recorded. Based upon the analysis of intensities, wavelengths, and band patterns of spectral emission bands, the spatial qualitative elemental composition of the shell samples can be determined. Raman spectra were also recorded and correlated to molecules in the sample. By analyzing these measurements using LIBS-Raman spectroscopic techniques, we will be able to see how the local environment is effecting growth, with the largest chemical disturbance in the area being the BP Oil Spill in the Gulf in 2010. Therefore if samples are selected from this period of time it may be possible to identify the effects on shell growth. UWF NIH MARC U-STAR 1T34GM110517-01, UWF Office of Undergraduate Research.

  9. Potential Alternatives for Advanced Energy Material Processing in High Performance Li-ion Batteries (LIBs) via Atmospheric Pressure Plasma Treatment

    NASA Astrophysics Data System (ADS)

    Duh, Jenq-Gong; Chuang, Shang-I.; Lan, Chun-Kai; Yang, Hao; Chen, Hsien-Wei

    2015-09-01

    A new processing technique by atmospheric pressure plasma (APP) jet treatment of LIBs was introduced. Ar/N2 plasma enhanced the high-rate anode performance of Li4Ti5O12. Oxygen vacancies were discovered and nitrogen doping were achieved by the surface reaction between pristine Li4Ti5O12 and plasma reactive species (N* and N2+). Electrochemical impedance spectra confirm that plasma modification increases Li ions diffusivity and reduces internal charge-transfer resistance, leading to a superior capacity (132 mAh/g) and excellent stability with negligible capacity decay over 100 cycles under 10C rate. Besides 2D material surface treatment, a specially designed APP generator that are feasible to modify 3D TiO2 powders is proposed. The rate capacity of 20 min plasma treated TiO2 exhibited 20% increment. Plasma diagnosis revealed that excited Ar and N2 was contributed to TiO2 surface reduction as companied by formation of oxygen vacancy. A higher amount of oxygen vacancy increased the chance for excited nitrogen doped onto surface of TiO2 particle. These findings promote the understanding of APP on processing anode materials in high performance LIBs.

  10. Laser-Induced Breakdown Spectroscopy (LIBS) for the Measurement of Spatial Structures and Fuel Distribution in Flames.

    PubMed

    Kotzagianni, Maria; Kakkava, Eirini; Couris, Stelios

    2016-04-01

    Laser-induced breakdown spectroscopy (LIBS) is used for the mapping of local structures (i.e., reactants and products zones) and for the determination of fuel distribution by means of the local equivalence ratio ϕ in laminar, premixed air-hydrocarbon flames. The determination of laser threshold energy to induce breakdown in the different zones of flames is employed for the identification and demarcation of the local structures of a premixed laminar flame, while complementary results about fuel concentration were obtained from measurements of the cyanogen (CN) band Β(2)Σ(+)--Χ(2)Σ(+), (Δυ = 0) at 388.3 nm and the ratio of the atomic lines of hydrogen (Hα) and oxygen (O(I)), Hα/O. The combination of these LIBS-based methods provides a relatively simple to use, rapid, and accurate tool for online and in situ combustion diagnostics, providing valuable information about the fuel distribution and the spatial variations of the local structures of a flame. PMID:26865582

  11. Short communication: limit feeding affects behavior patterns and feeding motivation of dairy heifers.

    PubMed

    Greter, A M; Miller-Cushon, E K; McBride, B W; Widowski, T M; Duffield, T F; DeVries, T J

    2015-02-01

    The study objective was to assess the effects of limit feeding dairy heifers on behavior patterns and feeding motivation. Ten Holstein heifers (291.6±39.2d of age, weighing 324.2±61.2kg; mean ± SD) were exposed to each of 2 dietary treatments, in a random order, over 2 successive 26-d treatment periods (14-d adaptation period and a 12-d data collection period) using a crossover design: (1) a high-forage total mixed ration (TMR), provided ad libitum (CON) and (2) a low-forage TMR, limit-fed at 2.05% body weight (LF). Heifers were fed daily at 1100h and motivation to access a low-nutritive feedstuff (straw) was assessed using a push-door apparatus at 2 time points: 3h after feed delivery (1400h) and 21h after feed delivery (0800h). The amount of weight pushed, weight pushed as percentage of body weight, and latency to access the push door were recorded on 3 different days for each heifer at each time point on each treatment. When fed CON, heifers had greater dry matter intake (12.9 vs. 7.2kg/d), greater feeding time (209.3 vs. 82.4min/d), greater ruminating time (452.2 vs. 318.3min/d), and slower rates of intake (0.06 vs. 0.09kg of dry matter/min) than when fed LF. Heifers fed LF pushed more weight as a percentage of body weight at 3h (4.5 vs. 1.9%) and 21h (9.3 vs. 2.8%) after feed delivery. At both 3 and 21h after feed delivery, latency to access the door was shorter for the LF heifers compared with the CON heifers (65 vs. 145 s). These results indicate that, in addition to decreasing feeding time, limit feeding increases motivation of heifers to access a low-nutritive feedstuff, possibly due to lack of satiety resulting from lack of physical fill or insufficient time spent foraging. PMID:25497811

  12. Ultraviolet asymptotics and singular dynamics of AdS perturbations

    NASA Astrophysics Data System (ADS)

    Craps, Ben; Evnin, Oleg; Vanhoof, Joris

    2015-10-01

    Important insights into the dynamics of spherically symmetric AdS-scalar field perturbations can be obtained by considering a simplified time-averaged theory accurately describing perturbations of amplitude ɛ on time-scales of order 1/ ɛ 2. The coefficients of the time-averaged equations are complicated expressions in terms of the AdS scalar field mode functions, which are in turn related to the Jacobi polynomials. We analyze the behavior of these coefficients for high frequency modes. The resulting asymptotics can be useful for understanding the properties of the finite-time singularity in solutions of the time-averaged theory recently reported in the literature. We highlight, in particular, the gauge dependence of this asymptotics, with respect to the two most commonly used gauges. The harsher growth of the coefficients at large frequencies in higher-dimensional AdS suggests strengthening of turbulent instabilities in higher dimensions. In the course of our derivations, we arrive at recursive relations for the coefficients of the time-averaged theory that are likely to be useful for evaluating them more efficiently in numerical simulations.

  13. Current trends in infant feeding.

    PubMed

    van der Elst, C W; Pick, W; Isaacs, S; Malan, A F

    1989-10-21

    This study examined aspects of newborn feeding in a maternity hospital and also investigated feeding practices during the first 6 months of life. Four hundred and fifty mothers were interviewed while in the maternity hospital. The majority (93%) had booked for their confinement and had attended antenatal clinics regularly. Most had had early contact with the baby at birth and stated that they thought breast-milk was best for the baby. Despite this only 54.6% had given breast-milk as the first feed and only 10% had done so within the first hour. Most mothers (54%) stated that they preferred a timed feeding routine to demand-feeding, while 86% planned to give water between feeds. The majority indicated they would change to formula feeds should they experience problems with breast-feeding. A follow-up visit of 78 mothers 6 months later showed that 50% breast-fed exclusively for 3 - 4 months and 23% for 6 - 7 months. When feeding problems occurred only 27% of the mothers utilised the local authority baby clinic for help. The main reasons given for stopping breast-feeds were insufficient milk, the need for employment and feeding problems. The implications of these findings are discussed. PMID:2799597

  14. New Features in ADS Labs

    NASA Astrophysics Data System (ADS)

    Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Di Milia, G.; Luker, J.; Murray, S. S.

    2013-01-01

    The NASA Astrophysics Data System (ADS) has been working hard on updating its services and interfaces to better support our community's research needs. ADS Labs is a new interface built on the old tried-and-true ADS Abstract Databases, so all of ADS's content is available through it. In this presentation we highlight the new features that have been developed in ADS Labs over the last year: new recommendations, metrics, a citation tool and enhanced fulltext search. ADS Labs has long been providing article-level recommendations based on keyword similarity, co-readership and co-citation analysis of its corpus. We have now introduced personal recommendations, which provide a list of articles to be considered based on a individual user's readership history. A new metrics interface provides a summary of the basic impact indicators for a list of records. These include the total and normalized number of papers, citations, reads, and downloads. Also included are some of the popular indices such as the h, g and i10 index. The citation helper tool allows one to submit a set of records and obtain a list of top 10 papers which cite and/or are cited by papers in the original list (but which are not in it). The process closely resembles the network approach of establishing "friends of friends" via an analysis of the citation network. The full-text search service now covers more than 2.5 million documents, including all the major astronomy journals, as well as physics journals published by Springer, Elsevier, the American Physical Society, the American Geophysical Union, and all of the arXiv eprints. The full-text search interface interface allows users and librarians to dig deep and find words or phrases in the body of the indexed articles. ADS Labs is available at http://adslabs.org

  15. The AdS central charge in string theory

    NASA Astrophysics Data System (ADS)

    Troost, Jan

    2011-11-01

    We evaluate the vacuum expectation value of the central charge operator in string theory in an AdS3 vacuum. Our calculation provides a rare non-zero one-point function on a spherical worldsheet. The evaluation involves the regularization both of a worldsheet ultraviolet divergence (associated to the infinite volume of the conformal Killing group), and a space-time infrared divergence (corresponding to the infinite volume of space-time). The two divergences conspire to give a finite result, which is the classical general relativity value for the central charge, corrected in bosonic string theory by an infinite series of tree level higher derivative terms.

  16. Small black holes in global AdS spacetime

    NASA Astrophysics Data System (ADS)

    Jokela, Niko; Pönni, Arttu; Vuorinen, Aleksi

    2016-04-01

    We study the properties of two-point functions and quasinormal modes in a strongly coupled field theory holographically dual to a small black hole in global anti-de Sitter spacetime. Our results are seen to smoothly interpolate between known limits corresponding to large black holes and thermal AdS space, demonstrating that the Son-Starinets prescription works even when there is no black hole in the spacetime. Omitting issues related to the internal space, the results can be given a field theory interpretation in terms of the microcanonical ensemble, which provides access to energy densities forbidden in the canonical description.

  17. Entanglement entropy and duality in AdS4

    NASA Astrophysics Data System (ADS)

    Bakas, Ioannis; Pastras, Georgios

    2015-07-01

    Small variations of the entanglement entropy δS and the expectation value of the modular Hamiltonian δE are computed holographically for circular entangling curves in the boundary of AdS4, using gravitational perturbations with general boundary conditions in spherical coordinates. Agreement with the first law of thermodynamics, δS = δE, requires that the line element of the entangling curve remains constant. In this context, we also find a manifestation of electric-magnetic duality for the entanglement entropy and the corresponding modular Hamiltonian, following from the holographic energy-momentum/Cotton tensor duality.

  18. Fake gaps in AdS3/CFT2

    NASA Astrophysics Data System (ADS)

    Belin, Alexandre; Castro, Alejandra; Hung, Ling-Yan

    2015-11-01

    We discuss properties of interpolating geometries in three dimensional gravity in the presence of a chiral anomaly. This anomaly, which introduces an unbalance between left and right central charges, is protected under RG flows. For this simple reason it is impossible to gap a system with such an anomaly. Our goal is to discuss how holography captures this basic and robust feature. We demonstrate the absence of a mass gap by analysing the linearized spectrum and holographic entanglement entropy of these backgrounds in the context of AdS3/CFT2.

  19. Pure Spinors in AdS and Lie Algebra Cohomology

    NASA Astrophysics Data System (ADS)

    Mikhailov, Andrei

    2014-10-01

    We show that the BRST cohomology of the massless sector of the Type IIB superstring on AdS5 × S 5 can be described as the relative cohomology of an infinite-dimensional Lie superalgebra. We explain how the vertex operators of ghost number 1, which correspond to conserved currents, are described in this language. We also give some algebraic description of the ghost number 2 vertices, which appears to be new. We use this algebraic description to clarify the structure of the zero mode sector of the ghost number two states in flat space, and initiate the study of the vertices of the higher ghost number.

  20. Internal structure of charged AdS black holes

    NASA Astrophysics Data System (ADS)

    Bhattacharjee, Srijit; Sarkar, Sudipta; Virmani, Amitabh

    2016-06-01

    When an electrically charged black hole is perturbed, its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached. Nevertheless, the mass inflation singularity is still a weak singularity: Although spacetime curvature becomes infinite, tidal distortions remain finite on physical objects attempting to cross it.

  1. Time-restricted feeding reduces adiposity in mice fed a high-fat diet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disruption of the circadian rhythm contributes to obesity. The present study investigated the effects of time-restricted feeding (TRF) of a high-fat diet on adiposity in male C57BL/6 mice. Three-week-old mice were fed a low-fat or high-fat diet (16% or 45% of energy from corn oil) ad libitum (ad l...

  2. Hydrocracker feeds olefin unit

    SciTech Connect

    Goossens, A.G.

    1986-11-01

    An ethylene plant integrated with a selective hydrocracker in a complex refinery can give an attractive payout, bearing in mind that results depend on the refinery's configuration and business environment. Feedstock and operating conditions are more flexible from only a moderate investment, particularly that to modify the steam cracker. Total product upgrading is high. Low grade vacuum-flashed distillates passed through a selective hydrocracker produce hydrogenated residue (hydrowax) having a value close to a naphtha as a feed to a steam cracker. The technology and economics of the concept are confirmed in a large industrial installations.

  3. Introducing ADS 2.0

    NASA Astrophysics Data System (ADS)

    Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Murray, S. S.

    2014-01-01

    In the spring of 1993, the Smithsonian/NASA Astrophysics Data System (ADS) first launched its bibliographic search system. It was known then as the ADS Abstract Service, a component of the larger Astrophysics Data System effort which had developed an interoperable data system now seen as a precursor of the Virtual Observatory. As a result of the massive technological and sociological changes in the field of scholarly communication, the ADS is now completing the most ambitious technological upgrade in its twenty-year history. Code-named ADS 2.0, the new system features: an IT platform built on web and digital library standards; a new, extensible, industrial strength search engine; a public API with various access control capabilities; a set of applications supporting search, export, visualization, analysis; a collaborative, open source development model; and enhanced indexing of content which includes the full-text of astronomy and physics publications. The changes in the ADS platform affect all aspects of the system and its operations, including: the process through which data and metadata are harvested, curated and indexed; the interface and paradigm used for searching the database; and the follow-up analysis capabilities available to the users. This poster describes the choices behind the technical overhaul of the system, the technology stack used, and the opportunities which the upgrade is providing us with, namely gains in productivity and enhancements in our system capabilities.

  4. Dust suppression in swine feed using soybean oil.

    PubMed

    Mankell, K O; Janni, K A; Walker, R D; Wilson, M E; Pettigrew, J E; Jacobson, L D; Wilcke, W F

    1995-04-01

    Dust generation from swine feed (corn-soybean meal diet) treated with soybean oil was investigated using a cement mixer in a plywood box. Airborne total dust concentrations in the box were measured gravimetrically using a vacuum pump and filters while 12-kg feed samples were constantly mixed. The treatment factors were soybean oil concentration (0, 1, and 3%), corn bulk density (normal, 730 kg/m3 and low, 600 kg/m3), time of oil addition (before vs after grinding the corn), and storage time (0, 7, and 14 d). The feed was a mixture of soybean meal, base mix, and adjusted amounts of ground corn and soybean oil. Adding soybean oil after grinding at 1 and 3% levels to feed made with normal-bulk density corn suppressed total dust generation (3.39 and .99 mg/m3, respectively) (P < .001) compared with the no oil treatment (29.1 mg/m3). The 3% soybean oil treatment suppressed dust generation (.99 mg/m3) more than the 1% soybean oil treatment (3.39 mg/m3) (P < .001). Adding soybean oil after grinding the corn suppressed dust generation more than adding the oil to the corn before grinding for every oil level (P < .001). More dust was generated by feed made from low-bulk density corn than by feed made with normal-bulk density corn at every oil level (P < .001). There was no evidence of any storage time or treatment x storage time interactions. PMID:7628976

  5. Enzyme feeding strategies for better fed-batch enzymatic hydrolysis of empty fruit bunch.

    PubMed

    Sugiharto, Yohanes Eko Chandra; Harimawan, Ardiyan; Kresnowati, Made Tri Ari Penia; Purwadi, Ronny; Mariyana, Rina; Andry; Fitriana, Hana Nur; Hosen, Hauna Fathmadinda

    2016-05-01

    Lignin inhibitory becomes a major obstacle for enzymatic hydrolysis of empty fruit bunch conducted in high solid loading. Since current technology required high enzyme loading, surfactant application could not effectively used since it is only efficient in low enzyme loading. In addition, it will increase final operation cost. Hence, another method namely "proportional enzyme feeding" was investigated in this paper. In this method, enzyme was added to reactor proportionally to substrate addition, different from conventional method ("whole enzyme feeding") where whole enzyme was added prior to hydrolysis process started. Proportional enzyme feeding could increase enzymatic digestibility and glucose concentration up to 26% and 12% respectively, compared to whole enzyme feeding for hydrolysis duration more than 40h. If enzymatic hydrolysis was run less than 40h (25% solid loading), whole enzyme feeding is preferable. PMID:26881335

  6. Pulsed feeding during fed-batch Aspergillus oryzae fermentation leads to improved oxygen mass transfer.

    PubMed

    Bhargava, Swapnil; Wenger, Kevin S; Marten, Mark R

    2003-01-01

    Productivity in many fungal fermentations is detrimentally affected by high broth viscosity and consequent reduced oxygen mass transfer capacity. The goal here was to determine whether pulsed feeding of limiting carbon in a fungal fermentation could lead to reduced viscosity and improved oxygen mass transfer. As a model, an industrially relevant recombinant strain of Aspergillus oryzae was grown in carbon-limited, fed-batch mode. Maltodextrin was used as a carbon source and was added either continuously or in 1.5-min pulses, 3.5 min apart. In both feeding modes the same total amount of carbon was added, and carbon feed rate was at sufficiently low levels to ensure cultures were always carbon-limited. Compared to continuous feeding, pulsed addition of substrate led to smaller fungal elements, which resulted in a significant reduction in broth viscosity. This in turn led to higher dissolved oxygen concentrations and increased oxygen uptake rates during pulsed feeding. PMID:12790687

  7. Critical gravity on AdS2 spacetimes

    NASA Astrophysics Data System (ADS)

    Myung, Yun Soo; Kim, Yong-Wan; Park, Young-Jai

    2011-09-01

    We study the critical gravity in two-dimensional anti-de Sitter (AdS2) spacetimes, which was obtained from the cosmological topologically massive gravity (TMGΛ) in three dimensions by using the Kaluza-Klein dimensional reduction. We perform the perturbation analysis around AdS2, which may correspond to the near-horizon geometry of the extremal Banados, Teitelboim, and Zanelli (BTZ) black hole obtained from the TMGΛ with identification upon uplifting three dimensions. A massive propagating scalar mode δF satisfies the second-order differential equation away from the critical point of K=l, whose solution is given by the Bessel functions. On the other hand, δF satisfies the fourth-order equation at the critical point. We exactly solve the fourth-order equation, and compare it with the log gravity in two dimensions. Consequently, the critical gravity in two dimensions could not be described by a massless scalar δFml and its logarithmic partner δFlog⁡4th.

  8. Conserved charges in timelike warped AdS3 spaces

    NASA Astrophysics Data System (ADS)

    Donnay, L.; Fernández-Melgarejo, J. J.; Giribet, G.; Goya, A.; Lavia, E.

    2015-06-01

    We consider the timelike version of warped anti-de Sitter space (WAdS), which corresponds to the three-dimensional section of the Gödel solution of four-dimensional cosmological Einstein equations. This geometry presents closed timelike curves (CTCs), which are inherited from its four-dimensional embedding. In three dimensions, this type of solution can be supported without matter provided the graviton acquires mass. Here, among the different ways to consistently give mass to the graviton in three dimensions, we consider the parity-even model known as new massive gravity (NMG). In the bulk of timelike WAdS3 space, we introduce defects that, from the three-dimensional point of view, represent spinning massive particlelike objects. For this type of source, we investigate the definition of quasilocal gravitational energy as seen from infinity, far beyond the region where the CTCs appear. We also consider the covariant formalism applied to NMG to compute the mass and the angular momentum of spinning particlelike defects and compare the result with the one obtained by means of the quasilocal stress tensor. We apply these methods to special limits in which the WAdS3 solutions coincide with locally AdS3 and locally AdS2×R spaces. Finally, we make some comments about the asymptotic symmetry algebra of asymptotically WAdS3 spaces in NMG.

  9. Primordial fluctuations from complex AdS saddle points

    NASA Astrophysics Data System (ADS)

    Hertog, Thomas; van der Woerd, Ellen

    2016-02-01

    One proposal for dS/CFT is that the Hartle-Hawking (HH) wave function in the large volume limit is equal to the partition function of a Euclidean CFT deformed by various operators. All saddle points defining the semiclassical HH wave function in cosmology have a representation in which their interior geometry is part of a Euclidean AdS domain wall with complex matter fields. We compute the wave functions of scalar and tensor perturbations around homogeneous isotropic complex saddle points, turning on single scalar field matter only. We compare their predictions for the spectra of CMB perturbations with those of a different dS/CFT proposal based on the analytic continuation of inflationary universes to real asymptotically AdS domain walls. We find the predictions of both bulk calculations agree to first order in the slow roll parameters, but there is a difference at higher order which, we argue, is a signature of the HH state of the fluctuations.

  10. Advanced Liquid Feed Experiment

    NASA Astrophysics Data System (ADS)

    Distefano, E.; Noll, C.

    1993-06-01

    The Advanced Liquid Feed Experiment (ALFE) is a Hitchhiker experiment flown on board the Shuttle of STS-39 as part of the Space Test Payload-1 (STP-1). The purpose of ALFE is to evaluate new propellant management components and operations under the low gravity flight environment of the Space Shuttle for eventual use in an advanced spacecraft feed system. These components and operations include an electronic pressure regulator, an ultrasonic flowmeter, an ultrasonic point sensor gage, and on-orbit refill of an auxiliary propellant tank. The tests are performed with two transparent tanks with dyed Freon 113, observed by a camera and controlled by ground commands and an on-board computer. Results show that the electronic pressure regulator provides smooth pressure ramp-up, sustained pressure control, and the flexibility to change pressure settings in flight. The ultrasonic flowmeter accurately measures flow and detects gas ingestion. The ultrasonic point sensors function well in space, but not as a gage during sustained low-gravity conditions, as they, like other point gages, are subject to the uncertainties of propellant geometry in a given tank. Propellant transfer operations can be performed with liquid-free ullage equalization at a 20 percent fill level, gas-free liquid transfer from 20-65 percent fill level, minimal slosh, and can be automated.

  11. Influence of coagulation factor x on in vitro and in vivo gene delivery by adenovirus (Ad) 5, Ad35, and chimeric Ad5/Ad35 vectors.

    PubMed

    Greig, Jenny A; Buckley, Suzanne Mk; Waddington, Simon N; Parker, Alan L; Bhella, David; Pink, Rebecca; Rahim, Ahad A; Morita, Takashi; Nicklin, Stuart A; McVey, John H; Baker, Andrew H

    2009-10-01

    The binding of coagulation factor X (FX) to the hexon of adenovirus (Ad) 5 is pivotal for hepatocyte transduction. However, vectors based on Ad35, a subspecies B Ad, are in development for cancer gene therapy, as Ad35 utilizes CD46 (which is upregulated in many cancers) for transduction. We investigated whether interaction of Ad35 with FX influenced vector tropism using Ad5, Ad35, and Ad5/Ad35 chimeras: Ad5/fiber(f)35, Ad5/penton(p)35/f35, and Ad35/f5. Surface plasmon resonance (SPR) revealed that Ad35 and Ad35/f5 bound FX with approximately tenfold lower affinities than Ad5 hexon-containing viruses, and electron cryomicroscopy (cryo-EM) demonstrated a direct Ad35 hexon:FX interaction. The presence of physiological levels of FX significantly inhibited transduction of vectors containing Ad35 fibers (Ad5/f35, Ad5/p35/f35, and Ad35) in CD46-positive cells. Vectors were intravenously administered to CD46 transgenic mice in the presence and absence of FX-binding protein (X-bp), resulting in reduced liver accumulation for all vectors. Moreover, Ad5/f35 and Ad5/p35/f35 efficiently accumulated in the lung, whereas Ad5 demonstrated poor lung targeting. Additionally, X-bp significantly reduced lung genome accumulation for Ad5/f35 and Ad5/p35/f35, whereas Ad35 was significantly enhanced. In summary, vectors based on the full Ad35 serotype will be useful vectors for selective gene transfer via CD46 due to a weaker FX interaction compared to Ad5. PMID:19603000

  12. Adding value to your work.

    PubMed

    Chambers, D W

    1998-01-01

    Dentists and many staff enjoy characteristics of work associated with high levels of satisfaction and performance. Although value can be added to oral health care professionals' jobs through enlargement, enrichment, rotations, and autonomous work groups, there are limits to these techniques. Controlling work performance by means of rewards is risky. Probably the most effective means of adding value to jobs is through the Quality of Work Life approach, concentrating on job design and placement to make work meaningful and autonomous and to provide feedback. PMID:9697373

  13. Feed preference in pigs: relationship with feed particle size and texture.

    PubMed

    Solà-Oriol, D; Roura, E; Torrallardona, D

    2009-02-01

    In previous studies, we observed important differences in the feed preferences of pigs resulting from changes in only 1 dietary ingredient. The present experiment was conducted to study the relationship between the feed preference values of feeds reported previously and their particle size and texture characteristics. The effect of individual feed ingredients was studied when added to a common basal diet. In addition to the basal diet, which included rice, a soybean meal product containing 56% CP, sunflower oil, and wheat bran, a total of 126 diets were studied. Of these, 63 were prepared by replacing the rice in the basal diet with another cereal, 29 by replacing the soybean product with different protein sources, 19 by replacing the sunflower oil with different lipid sources, and 6 by replacing the wheat bran with different fiber sources. Cereals were studied at inclusion rates of 150, 300, and 600 g x kg(-1); protein sources were studied at 50, 100, and 200 g x kg(-1); lipids were studied at 15, 30, and 100 g x kg(-1); and fiber sources were studied at 65 and 130 g x kg(-1). The particle size profile of all the diets was determined by using a 9-screen sieve shaker. The geometric mean particle size, particle size uniformity, number of particles per gram, surface area (cm(2) x g(-1)), and percentage of fine (passing through a 250-microm sieve) and coarse particles (remaining in a 2,000-microm sieve) were calculated. The texture properties (hardness, fragility, chewing work, and adhesiveness) of the feeds were also determined by using a texture analyzer. The Pearson correlation coefficients of these variables with feed preference were as follows: geometric mean particle size (r = 0.07; P = 0.45), particle size uniformity (r = 0.16; P = 0.07), number of particles per gram (r = -0.05; P = 0.61), surface area (r = -0.07; P = 0.46), percentage of coarse particles (r = 0.04; P = 0.65), percentage of fine particles (r = -0.12; P = 0.19), hardness (r = -0.21; P = 0

  14. Creating Tomorrow's Technologists: Contrasting Information Technology Curriculum in North American Library and Information Science Graduate Programs against Code4lib Job Listings

    ERIC Educational Resources Information Center

    Maceli, Monica

    2015-01-01

    This research study explores technology-related course offerings in ALA-accredited library and information science (LIS) graduate programs in North America. These data are juxtaposed against a text analysis of several thousand LIS-specific technology job listings from the Code4lib jobs website. Starting in 2003, as a popular library technology…

  15. Exploring the Relationship between Patron Type, Carnegie Classification, and Satisfaction with Library Services: An Analysis of LibQUAL+® Results

    ERIC Educational Resources Information Center

    Guder, Christopher S.

    2012-01-01

    The purpose of this study was to explore how faculty and students responded to the Information Control section of the LibQUAL+® survey at two libraries with different Carnegie Classifications. As one of the institutions being studied was considering a shift from a research institution to one more focused on teaching and learning, this study used…

  16. Development of Wide Band Feeds

    NASA Astrophysics Data System (ADS)

    Ujihara, H.; Ichikawa, R.

    2012-12-01

    Wide Band feeds are being developed at NICT, NAOJ, and some universities in Japan for VLBI2010, SKA, and MARBLE. SKA, the Square Kilometre Array, will comprise thousands of radio telescopes with square kilometer aperture size for radio astronomy. MARBLE consists of small portable VLBI stations developed at NICT and GSI in Japan. They all need wide band feeds with a greater than 1:10 frequency ratio. Thus we have been studying wide band feeds with dual linear polarization for these applications.

  17. Value-added uses for crude glycerol--a byproduct of biodiesel production

    PubMed Central

    2012-01-01

    Biodiesel is a promising alternative, and renewable, fuel. As its production increases, so does production of the principle co-product, crude glycerol. The effective utilization of crude glycerol will contribute to the viability of biodiesel. In this review, composition and quality factors of crude glycerol are discussed. The value-added utilization opportunities of crude glycerol are reviewed. The majority of crude glycerol is used as feedstock for production of other value-added chemicals, followed by animal feeds. PMID:22413907

  18. Comparison of Laser Induced Breakdown Spectroscopy (LIBS) on Martian Meteorite NWA 7034 to ChemCam Observations at Gale Crater, Mars

    NASA Astrophysics Data System (ADS)

    Gordon, S.; Newsom, H. E.; Agee, C. B.; Santos, A. R.; Clegg, S. M.; Wiens, R. C.; Lasue, J.; Sautter, V.

    2014-12-01

    The ChemCam instrument on board the Mars Science Laboratory (MSL) Curiosity rover uses laser-induced breakdown spectroscopy (LIBS) to analyze rock and soil targets on Mars from up to 7 m away. The Nd:KGW laser can shoot up to 1000 shots at one location and profile up to 1 mm depth into a rock. Identical LIBS instrumentation is located at Los Alamos National Laboratory and was used to analyze martian meteorite NWA 7034, a non-SNC basaltic breccia whose bulk composition matches the martian surface. Initial LIBS analysis of NWA 7034 included observations on two basaltic clasts in the meteorite. Electron microprobe analysis (EPMA) was performed on the two clasts for comparison with elemental compositions measured using LIBS. The two instruments give similar compositions of major oxides within the error of both techniques. EPMA analysis was also completed on three light-toned clasts and a dark-toned clast in the meteorite. The light-toned clasts have Al/Si vs. (Fe+Mg)/Si compositions ranging from felsic to mafic, and the dark-toned clast shows a mafic composition. A Sammon's map was created to compare LIBS data for NWA 7034 and ChemCam targets Stark, Crestaurum, Link, Portage, Jake_M, Mara, Thor_Lake, Coronation, Pearson, and Prebble. This nonlinear statistical mapping technique is used for clustering assessment of LIBS data in two dimensions. The map shows NWA 7034 clustering in its own location, and the closest similar ChemCam rock targets are La_Reine and Ashuamipi, which are both coarse grained targets that have a mafic component consistent with augite. The most similar ChemCam soil targets are the Crestaurum and Portage. Creation of maps with a greater number of targets will show more of the similarities between NWA 7034 and ChemCam target rocks and soils. Further analysis will compare NWA 7034 LIBS data, data from the paired meteorite NWA 7533, and a variety of ChemCam targets that are similar in morphology and texture.

  19. Organic and Nonorganic Feeding Disorders.

    PubMed

    Rybak, Anna

    2015-01-01

    Feeding is one of the most important interactions between caregiver and child in the first few years of life and even later on in handicapped children. Feeding disorders can present as food refusal or low quantity of food intake due to behavioral issues or underlying organic conditions. This situation concerns mostly infants and children below 6 years of age; however, feeding problems can appear also later on in life. Feeding disorders are a concern for over 10-25% of parents of otherwise healthy children below 3 years of age, but only 1-5% of infants and toddlers suffer from severe feeding problems resulting in failure to thrive. In case of premature infants or neurologically disabled children, this rate is much higher. Feeding disorders may appear as an isolated problem, mainly due to negative behaviors during feeding, or as a concomitant disorder with an underlying organic disease or structural anomaly. The newest classification also includes the feeding style presented by the caregiver (responsive, controlling, indulgent or neglectful) as a separate cause of feeding disorders. PMID:26226993

  20. How to Feed Cleft Patient?

    PubMed Central

    Khan, Saima Yunus

    2013-01-01

    ABSTRACT Cleft lip and palate patients have all rights like other normal individuals, to enjoy the benefits of nourishment. Knowledge has to be there about the different feeding positions like straddle, dancer hand position along with the use of specially designed bottles and nipples. Parent's should be trained about the correct positions of feeding, in extreme of the cases in which parents are not able to follow these instructions, feeding obturators can be given. How to cite this article: Jindal MK, Khan SY. How to Feed Cleft Patient? Int J Clin Pediatr Dent 2013;6(2):100-103. PMID:25206201

  1. Misaligned feeding impairs memories

    PubMed Central

    Loh, Dawn H; Jami, Shekib A; Flores, Richard E; Truong, Danny; Ghiani, Cristina A; O’Dell, Thomas J; Colwell, Christopher S

    2015-01-01

    Robust sleep/wake rhythms are important for health and cognitive function. Unfortunately, many people are living in an environment where their circadian system is challenged by inappropriate meal- or work-times. Here we scheduled food access to the sleep time and examined the impact on learning and memory in mice. Under these conditions, we demonstrate that the molecular clock in the master pacemaker, the suprachiasmatic nucleus (SCN), is unaltered while the molecular clock in the hippocampus is synchronized by the timing of food availability. This chronic circadian misalignment causes reduced hippocampal long term potentiation and total CREB expression. Importantly this mis-timed feeding resulted in dramatic deficits in hippocampal-dependent learning and memory. Our findings suggest that the timing of meals have far-reaching effects on hippocampal physiology and learned behaviour. DOI: http://dx.doi.org/10.7554/eLife.09460.001 PMID:26652002

  2. Multiple feed powder splitter

    DOEpatents

    Lewis, Gary K.; Less, Richard M.

    2001-01-01

    A device for providing uniform powder flow to the nozzles when creating solid structures using a solid fabrication system such as the directed light fabrication (DLF) process. In the DLF process, gas entrained powders are passed through the focal point of a moving high-power laser light which fuses the particles in the powder to a surface being built up in layers. The invention is a device providing uniform flow of gas entrained powders to the nozzles of the DLF system. The device comprises a series of modular splitters which are slidably interconnected and contain an integral flow control mechanism. The device can take the gas entrained powder from between one to four hoppers and split the flow into eight tubular lines which feed the powder delivery nozzles of the DLF system.

  3. Multiple feed powder splitter

    DOEpatents

    Lewis, Gary K.; Less, Richard M.

    2002-01-01

    A device for providing uniform powder flow to the nozzles when creating solid structures using a solid fabrication system such as the directed light fabrication (DLF) process. In the DLF process, gas entrained powders are passed through the focal point of a moving high-power laser light which fuses the particles in the powder to a surface being built up in layers. The invention is a device providing uniform flow of gas entrained powders to the nozzles of the DLF system. The device comprises a series of modular splitters which are slidably interconnected and contain an integral flow control mechanism. The device can take the gas entrained powder from between one to four hoppers and split the flow into eight tubular lines which feed the powder delivery nozzles of the DLF system.

  4. [Influence of feeding patterns on the development of teeth, dentition and jaw in children].

    PubMed

    Wang, Xiao-tong; Ge, Li-hong

    2015-02-18

    Breastfeeding has been recognized as the most natural and nutritious way of feeding babies. Besides the nutritional, immunological and emotional benefits, breastfeeding promotes a healthy stomatognathic system. First of all, the nutrients and minerals in maternal milk are easy to be absorbed by the infants, which contributes to the mineralization of the teeth, and suppress the propagation of bacteria on the teeth. Though the jury is still out on whether breastfeeding can prevent Early Childhood Caries (ECC), it is definite that we should pay attention to feeding at night and the oral hygiene of the babies. Secondly, the method of feeding is closely bound up with the development of dentition and jaw. Breast- and bottle-feeding involve different orofacial muscles, which possibly have different effects on the harmonic growth of maxilla and dental arches. Meanwhile, breathing, swallowing and mastication should be developing in harmony, and differences exist in the learning of the coordinated movement between breast feeding and bottle feeding children. Bottle feeding had been proved to be closely related with the non-nutritive sucking habits which can cause malocclusion. At last, it should be pointed out that breast feeding should be the only feeding source in the first 6 months of life, then supplementary foods should be added. And prolonged bottle feeding should be avoided. We can see that breast feeding is definitely good for the infants, but the reality is not optimistic in our country. PMID:25686355

  5. Feeding a future world.

    PubMed

    Hinrichsen, D

    1998-01-01

    This article provides an overview of future prospects for feeding the world's growing population. The discussion focuses on obstacles such as limited agricultural land, degraded soil and water, and water shortages. The evidence suggests that sustainability is declining, especially in poor, food-deficit countries with growing populations. The world is segregated into the haves, the poor have-nots, and the rich have-nots. North America, Europe, and Australia have enough cropland to feed their populations. The poor have-nots are located mostly in sub-Saharan Africa, 7 countries each in the Middle East and Latin America, 6 in Oceania, and the rest in Central and South Asia. The poor have-nots amount to 3 billion out of 6 billion total population. The rich have-nots include countries such as Japan and Singapore, plus China, Indonesia, Peru, Chile, and Saudi Arabia and other Gulf states. The rich have-nots must import food. The world grain harvest is no longer tripling. Per person yields have declined. Increasing food productivity must rely on existing lands. The size of family farms has declined. Almost 2 billion hectares of crop and grazing land is degraded. Yields from irrigated land that are 33% of world food supply have declined. In 1990, 28 countries with 335 million people faced chronic water shortages or scarcity. Water is being polluted. Fish stocks are being depleted. Genetic diversity is being lost. In 182 food deficit countries, population growth must be slowed, and agriculture must be sustainable. Food is neither produced nor consumed equitably. Malnutrition is caused by poverty. Food security cannot be achieved if land and water become increasingly degraded or lost. PMID:12348766

  6. Higher-derivative superparticle in AdS3 space

    NASA Astrophysics Data System (ADS)

    Kozyrev, Nikolay; Krivonos, Sergey; Lechtenfeld, Olaf

    2016-03-01

    Employing the coset approach we construct component actions for a superparticle moving in AdS3 with N =(2 ,0 ), D =3 supersymmetry partially broken to N =2 , d =1 . These actions may contain higher time-derivative terms, which are chosen to possess the same (super)symmetries as the free superparticle. In terms of the nonlinear-realization superfields, the component actions always take a simpler form when written in terms of covariant Cartan forms. We also consider in detail the reduction to the nonrelativistic case and construct the corresponding action of a Newton-Hooke superparticle and its higher-derivative generalizations. The structure of these higher time-derivative generalizations is completely fixed by invariance under the supersymmetric Newton-Hooke algebra extended by two central charges.

  7. Aspects of warped AdS3/CFT2 correspondence

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Zhang, Jia-Ju; Zhang, Jian-Dong; Zhong, De-Liang

    2013-04-01

    In this paper we apply the thermodynamics method to investigate the holographic pictures for the BTZ black hole, the spacelike and the null warped black holes in three-dimensional topologically massive gravity (TMG) and new massive gravity (NMG). Even though there are higher derivative terms in these theories, the thermodynamics method is still effective. It gives consistent results with the ones obtained by using asymptotical symmetry group (ASG) analysis. In doing the ASG analysis we develop a brute-force realization of the Barnich-Brandt-Compere formalism with Mathematica code, which also allows us to calculate the masses and the angular momenta of the black holes. In particular, we propose the warped AdS3/CFT2 correspondence in the new massive gravity, which states that quantum gravity in the warped spacetime could holographically dual to a two-dimensional CFT with {c_R}={c_L}=24 /{Gm{β^2√{{2( {21-4{β^2}} )}}}}.

  8. Thermodynamics of charged Lovelock: AdS black holes

    NASA Astrophysics Data System (ADS)

    Prasobh, C. B.; Suresh, Jishnu; Kuriakose, V. C.

    2016-04-01

    We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime.

  9. Vortex hair on AdS black holes

    NASA Astrophysics Data System (ADS)

    Gregory, Ruth; Gustainis, Peter C.; Kubizňák, David; Mann, Robert B.; Wills, Danielle

    2014-11-01

    We analyse vortex hair for charged rotating asymptotically AdS black holes in the abelian Higgs model. We give analytical and numerical arguments to show how the vortex interacts with the horizon of the black hole, and how the solution extends to the boundary. The solution is very close to the corresponding asymptotically flat vortex, once one transforms to a frame that is non-rotating at the boundary. We show that there is a Meissner effect for extremal black holes, with the vortex flux being expelled from sufficiently small black holes. The phase transition is shown to be first order in the presence of rotation, but second order without rotation. We comment on applications to holography.

  10. An investigation of AdS2 backreaction and holography

    NASA Astrophysics Data System (ADS)

    Engelsöy, Julius; Mertens, Thomas G.; Verlinde, Herman

    2016-07-01

    We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski [1] and develop a 1d effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1d version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.

  11. Intrinsic ultraviolet luminescence of LiB3O5 single crystals under inner-shell excitation

    NASA Astrophysics Data System (ADS)

    Ogorodnikov, I. N.; Pustovarov, V. A.; Kirm, M.

    2004-05-01

    Ultraviolet photoluminescence (PL) of LiB3O5 (LBO) crystals has been studied under selective excitation by photons in the vacuum ultraviolet and ultrasoft x-ray regions, including the K-absorption edges of the Li and B cations and O anion. Radiative recombination of electron-hole pairs was established to be the main channel of the intrinsic PL excitation at 4.2 eV. Features were observed in the PL excitation spectra near the lithium and boron K-absorption edges originating from excitation of the cation 1 s core excitons. Experimental evidence of the multiplication of Li 1 s excitons in LBO was obtained. It is shown that excitation of the O 1 s core excitons does not affect the PL yield noticeably. The differences in the appearance of the Li, B, and O 1 s excitons in the excitation spectra of the LBO ultraviolet PL are discussed.

  12. Quantitative analysis of aluminum samples in He ambient gas at different pressures in a thick LIBS plasma

    NASA Astrophysics Data System (ADS)

    Rezaei, Fatemeh; Tavassoli, Seyed Hassan

    2015-09-01

    In this paper, the influences of He ambient gas on aluminum emissions are investigated by experimental analysis of LIBS spectrum. Plasma is produced by focusing of a Nd:YAG laser pulse at a wavelength of 1064 nm on Al standard samples. In this work, the effects of helium atmosphere at different pressures on the amount of spectral self-absorption are studied. The results are discussed by utilizing two approaches: the curve of growth and calibration curve. It is seen that by increasing the gas pressure, the self-absorption enhances. Also, a new method of applying one standard sample instead of other traditional techniques is introduced for concentration prediction. The presented method would be helpful for the situation in which supplying standard samples is not very easy. Then, the accuracy of this new method can be checked by comparison of concentration prediction of the standard samples with their real concentrations.

  13. High-power nanosecond optical parametric oscillator based on a long LiB 3O 5 crystal

    NASA Astrophysics Data System (ADS)

    Li, H. Q.; Zhang, H. B.; Bao, Z.; Zhang, J.; Sun, Z. P.; Kong, Y. P.; Bi, Y.; Lin, X. C.; Yao, A. Y.; Wang, G. L.; Hou, W.; Li, R. N.; Cui, D. F.; Xu, Z. Y.

    2004-03-01

    We report on a compact high average power optical parametric oscillator (OPO) pumped by an all-solid-state nanosecond 532 nm laser. Based on the merit of non-critically phase-matched crystal without walk-off effect, a 50-mm-long LiB 3O 5 (LBO) crystal is used as OPO nonlinear crystal to enhance the conversion efficiency and increase the output power. With the available mirror set, continuous tuning from 778 to 1036 nm for signal wave is obtained by changing LBO phase-matching temperature. The maximum average power of signal output is up to 9.4 W at 900 nm for pump power of 18 W inside the LBO crystal, corresponding to a conversion efficiency of 52% only for the signal output. This is, to the best of our knowledge, the highest signal average power generated by nanosecond OPO in single bulk LBO.

  14. Systematics of Coupling Flows in AdS Backgrounds

    SciTech Connect

    Goldberger, Walter D.; Rothstein, Ira Z.

    2003-03-18

    We give an effective field theory derivation, based on the running of Planck brane gauge correlators, of the large logarithms that arise in the predictions for low energy gauge couplings in compactified AdS}_5 backgrounds, including the one-loop effects of bulk scalars, fermions, and gauge bosons. In contrast to the case of charged scalars coupled to Abelian gauge fields that has been considered previously in the literature, the one-loop corrections are not dominated by a single 4D Kaluza-Klein mode. Nevertheless, in the case of gauge field loops, the amplitudes can be reorganized into a leading logarithmic contribution that is identical to the running in 4D non-Abelian gauge theory, and a term which is not logarithmically enhanced and is analogous to a two-loop effect in 4D. In a warped GUT model broken by the Higgs mechanism in the bulk,we show that the matching scale that appears in the large logarithms induced by the non-Abelian gauge fields is m_{XY}^2/k where m_{XY} is the bulk mass of the XY bosons and k is the AdS curvature. This is in contrast to the UV scale in the logarithmic contributions of scalars, which is simply the bulk mass m. Our results are summarized in a set of simple rules that can be applied to compute the leading logarithmic predictions for coupling constant relations within a given warped GUT model. We present results for both bulk Higgs and boundary breaking of the GUT gauge

  15. Holography beyond conformal invariance and AdS isometry?

    SciTech Connect

    Barvinsky, A. O.

    2015-03-15

    We suggest that the principle of holographic duality be extended beyond conformal invariance and AdS isometry. Such an extension is based on a special relation between functional determinants of the operators acting in the bulk and on its boundary, provided that the boundary operator represents the inverse propagators of the theory induced on the boundary by the Dirichlet boundary value problem in the bulk spacetime. This relation holds for operators of a general spin-tensor structure on generic manifolds with boundaries irrespective of their background geometry and conformal invariance, and it apparently underlies numerous O(N{sup 0}) tests of the AdS/CFT correspondence, based on direct calculation of the bulk and boundary partition functions, Casimir energies, and conformal anomalies. The generalized holographic duality is discussed within the concept of the “double-trace” deformation of the boundary theory, which is responsible in the case of large-N CFT coupled to the tower of higher-spin gauge fields for the renormalization group flow between infrared and ultraviolet fixed points. Potential extension of this method beyond the one-loop order is also briefly discussed.

  16. Holography beyond conformal invariance and AdS isometry?

    NASA Astrophysics Data System (ADS)

    Barvinsky, A. O.

    2015-03-01

    We suggest that the principle of holographic duality be extended beyond conformal invariance and AdS isometry. Such an extension is based on a special relation between functional determinants of the operators acting in the bulk and on its boundary, provided that the boundary operator represents the inverse propagators of the theory induced on the boundary by the Dirichlet boundary value problem in the bulk spacetime. This relation holds for operators of a general spin-tensor structure on generic manifolds with boundaries irrespective of their background geometry and conformal invariance, and it apparently underlies numerous O( N 0) tests of the AdS/CFT correspondence, based on direct calculation of the bulk and boundary partition functions, Casimir energies, and conformal anomalies. The generalized holographic duality is discussed within the concept of the "double-trace" deformation of the boundary theory, which is responsible in the case of large- N CFT coupled to the tower of higher-spin gauge fields for the renormalization group flow between infrared and ultraviolet fixed points. Potential extension of this method beyond the one-loop order is also briefly discussed.

  17. Islands of stability and recurrence times in AdS

    NASA Astrophysics Data System (ADS)

    Green, Stephen R.; Maillard, Antoine; Lehner, Luis; Liebling, Steven L.

    2015-10-01

    We study the stability of anti-de Sitter (AdS) spacetime to spherically symmetric perturbations of a real scalar field in general relativity. Further, we work within the context of the "two time framework" (TTF) approximation, which describes the leading nonlinear effects for small amplitude perturbations, and is therefore suitable for studying the weakly turbulent instability of AdS—including both collapsing and noncollapsing solutions. We have previously identified a class of quasiperiodic (QP) solutions to the TTF equations, and in this paper we analyze their stability. We show that there exist several families of QP solutions that are stable to linear order, and we argue that these solutions represent islands of stability in TTF. We extract the eigenmodes of small oscillations about QP solutions, and we use them to predict approximate recurrence times for generic noncollapsing initial data in the full (non-TTF) system. Alternatively, when sufficient energy is driven to high-frequency modes, as occurs for initial data far from a QP solution, the TTF description breaks down as an approximation to the full system. Depending on the higher order dynamics of the full system, this often signals an imminent collapse to a black hole.

  18. Effect of Sample Preparation on the Discrimination of Bacterial Isolates Cultured in Liquid Nutrient Media Using Laser-Induced Breakdown Spectroscopy (LIBS).

    PubMed

    Gamble, Gary R; Park, Bosoon; Yoon, Seung-Chul; Lawrence, Kurt C

    2016-03-01

    Laser-induced breakdown spectroscopy (LIBS) is used as the basis for discrimination between two genera of gram-negative bacteria and two genera of gram-positive bacteria representing pathogenic threats commonly found in poultry processing rinse waters. Because LIBS-based discrimination relies primarily upon the relative proportions of inorganic cell components including Na, K, Mg, and Ca, this study aims to determine the effects of trace mineral content and pH found in the water source used to isolate the bacteria upon the reliability of the resulting discriminant analysis. All four genera were cultured using tryptic soy agar (TSA) as the nutrient medium, and were grown under identical environmental conditions. The only variable introduced is the source water used to isolate the cultured bacteria. Cultures of each bacterium were produced using deionized (DI) water under two atmosphere conditions, reverse osmosis (RO) water, tap water, phosphate buffered saline (PBS) water, and TRIS buffered water. After 3 days of culture growth, the bacteria were centrifuged and washed three times in the same water source. Bacteria were then freeze dried, mixed with microcrystalline cellulose, and a pellet was made for LIBS analysis. Principal component analysis (PCA) was used to extract related variations in LIBS spectral data among the four bacteria genera and six water types used to isolate the bacteria, and Mahalanobis discriminant analysis (MDA) was used for classification. Results indicate not only that the four genera can be discriminated from each other in each water type, but that each genus can be discriminated by water type used for isolation. It is concluded that in order for LIBS to be a reliable and repeatable method for discrimination of bacteria grown in liquid nutrient media, care must be taken to insure that the water source used in purification of the culture be precisely controlled regarding pH, ionic strength, and proportionate amounts of mineral cations

  19. Fast detection and characterization of organic and inorganic gunshot residues on the hands of suspects by CMV-GC-MS and LIBS.

    PubMed

    Tarifa, Anamary; Almirall, José R

    2015-05-01

    A rapid method for the characterization of both organic and inorganic components of gunshot residues (GSR) is proposed as an alternative tool to facilitate the identification of a suspected shooter. In this study, two fast screening methods were developed and optimized for the detection of organic compounds and inorganic components indicative of GSR presence on the hands of shooters and non-shooters. The proposed methods consist of headspace extraction of volatile organic compounds using a capillary microextraction of volatiles (CMV) device previously reported as a high-efficiency sampler followed by detection by GC-MS. This novel sampling technique has the potential to yield fast results (<2min sampling) and high sensitivity capable of detecting 3ng of diphenylamine (DPA) and 8ng of nitroglycerine (NG). Direct analysis of the headspace of over 50 swabs collected from the hands of suspected shooters (and non-shooters) provides information regarding VOCs present on their hands. In addition, a fast laser induced breakdown spectroscopy (LIBS) screening method for the detection of the inorganic components indicative of the presence of GSR (Sb, Pb and Ba) is described. The sampling method for the inorganics consists of liquid extraction of the target elements from the same cotton swabs (previously analyzed for VOCs) and an additional 30 swab samples followed by spiking 1μL of the extract solution onto a Teflon disk and then analyzed by LIBS. Advantages of LIBS include fast analysis (~12s per sample) and high selectivity and sensitivity, with expected LODs 0.1-18ng for each of the target elements after sampling. The analytical performance of the LIBS method is also compared to previously reported methods (inductively coupled plasma-optical emission spectroscopy). The combination of fast CMV sampling, unambiguous organic compound identification with GC-MS and fast LIBS analysis provides the basis for a new comprehensive screening method for GSR. PMID:25934368

  20. Laser-induced breakdown spectroscopy (LIBS), part I: review of basic diagnostics and plasma-particle interactions: still-challenging issues within the analytical plasma community.

    PubMed

    Hahn, David W; Omenetto, Nicoló

    2010-12-01

    Laser-induced breakdown spectroscopy (LIBS) has become a very popular analytical method in the last decade in view of some of its unique features such as applicability to any type of sample, practically no sample preparation, remote sensing capability, and speed of analysis. The technique has a remarkably wide applicability in many fields, and the number of applications is still growing. From an analytical point of view, the quantitative aspects of LIBS may be considered its Achilles' heel, first due to the complex nature of the laser-sample interaction processes, which depend upon both the laser characteristics and the sample material properties, and second due to the plasma-particle interaction processes, which are space and time dependent. Together, these may cause undesirable matrix effects. Ways of alleviating these problems rely upon the description of the plasma excitation-ionization processes through the use of classical equilibrium relations and therefore on the assumption that the laser-induced plasma is in local thermodynamic equilibrium (LTE). Even in this case, the transient nature of the plasma and its spatial inhomogeneity need to be considered and overcome in order to justify the theoretical assumptions made. This first article focuses on the basic diagnostics aspects and presents a review of the past and recent LIBS literature pertinent to this topic. Previous research on non-laser-based plasma literature, and the resulting knowledge, is also emphasized. The aim is, on one hand, to make the readers aware of such knowledge and on the other hand to trigger the interest of the LIBS community, as well as the larger analytical plasma community, in attempting some diagnostic approaches that have not yet been fully exploited in LIBS. PMID:21144145

  1. Application of LIBS to the in-line process control of liquid high-alloy steel under pressure.

    PubMed

    Hubmer, Gerhard; Kitzberger, Reinhard; Mörwald, Karl

    2006-05-01

    A process optimization and control system called VAI-CON Chem has been developed that uses laser-induced breakdown spectroscopy (LIBS) to quasi-continuously chemically analyze liquid high-alloy steel under pressure. The beam from a Nd:YAG laser, located on safe ground and operating at its fundamental wavelength, is guided by a mirror system to a process tuyere below bath level. Passing through the approximately 1.5 m long tuyere, the beam is then focused onto the steel bath. Light emitted from the induced plasma passes back through the tuyere, which is coupled to a fiber optic cable that carries the information over a distance of approximately 10 m back to an Echelle spectrometer located beside the laser. Calibrations were performed using the complete system, located in a laboratory, during system testing. An induction furnace was used to simulate the AOD converter, wherein the samples were molten and superheated to a temperature of approximately 1600 degrees C and kept at a pressure of approximately 1.7 bar under an argon atmosphere. Twelve different high alloyed reference samples taken from normal AOD production with Fe concentrations of >48 wt.% and non-Fe element concentrations of up to 25 wt.% were available for calibration. The mean residual deviations (defined as the square root of the variance of the concentration ratios determined by LIBS and the reference element concentration ratios) obtained were close to those reported for other comparable high-alloy samples that were investigated at room temperature under normal atmospheric pressure. PMID:16550425

  2. Residual feed intake as a feed efficiency selection tool and its relationship with feed intake, performance and nutrient utilization in Murrah buffalo calves.

    PubMed

    Subhashchandra Bose, Bisitha Kattiparambil; Kundu, Shivlal Singh; Tho, Nguyen Thi Be; Sharma, Vijay Kumar; Sontakke, Umesh Balaji

    2014-04-01

    Residual feed intake (RFI) is the difference between the actual and expected feed intake of an animal based on its body weight and growth rate over a specific period. The objective of this study was to determine the RFI of buffalo calves using residuals from appropriate linear regression models involving dry matter intake (DMI), average daily gain (ADG) and mid-test metabolic body weight. Eighteen male Murrah buffalo calves of 5-7 months were selected and fed individually. A feeding trial using ad libitum feeding of total mixed ration (TMR, concentrate/roughage = 40:60) was conducted for 52 days in which the daily DMI, weekly body weight (BW) and growth rate of the calves were monitored. RFI of calves ranged from -0.20 to +0.23 kg/day. Mean DMI (in grams per kilogram of BW(0.75)) during the feeding trial period was significantly (P < 0.05) lower in low RFI group (79.66 g/kg BW(0.75)) compared to high RFI (87.74 g/kg BW(0.75)). Average initial BW, final BW and mid-test BW(0.75) did not differ (P > 0.05) between low and high RFI groups. Over the course of a trial period, low RFI group animals consumed 10% less feed compared to high RFI group of animals, yet performed in a comparable manner in terms of growth rate. Metabolizable energy for maintenance (MEm) was found to be significantly (P < 0.05) lower in low RFI group (13.54 MJ/100 kg BW) as compared to that of high RFI group (15.56 MJ/100 kg BW). The present study indicates that RFI is a promising selection tool for the selection of buffaloes for increased feed efficiency. PMID:24563229

  3. Scattering States in AdS/CFT

    SciTech Connect

    Fitzpatrick, A.Liam; Kaplan, Jared; /SLAC

    2012-02-14

    We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.

  4. ADS's Dexter Data Extraction Applet

    NASA Astrophysics Data System (ADS)

    Demleitner, M.; Accomazzi, A.; Eichhorn, G.; Grant, C. S.; Kurtz, M. J.; Murray, S. S.

    The NASA Astrophysics Data System (ADS) now holds 1.3 million scanned pages, containing numerous plots and figures for which the original data sets are lost or inaccessible. The availability of scans of the figures can significantly ease the regeneration of the data sets. For this purpose, the ADS has developed Dexter, a Java applet that supports the user in this process. Dexter's basic functionality is to let the user manually digitize a plot by marking points and defining the coordinate transformation from the logical to the physical coordinate system. Advanced features include automatic identification of axes, tracing lines and finding points matching a template. This contribution both describes the operation of Dexter from a user's point of view and discusses some of the architectural issues we faced during implementation.

  5. Infant Feeding: An Annotated Bibliography.

    ERIC Educational Resources Information Center

    Crowhurst, Christine Marie, Comp.; Kumer, Bonnie Lee, Comp.

    Intended for parents, health professionals and allied health workers, and others involved in caring for infants and young children, this annotated bibliography brings together in one selective listing a review of over 700 current publications related to infant feeding. Reflecting current knowledge in infant feeding, the bibliography has as its…

  6. Feed analyses and their interpretation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Compositional analysis is central to determining the nutritional value of feedstuffs. The utility of the values and how they should be used depends on how representative the feed subsample is, the nutritional relevance of the assays, analytical variability of the analyses, and whether a feed is suit...

  7. Enteral Tube Feeding and Pneumonia

    ERIC Educational Resources Information Center

    Gray, David Sheridan; Kimmel, David

    2006-01-01

    To determine the effects of enteral tube feeding on the incidence of pneumonia, we performed a retrospective review of all clients at our institution who had gastrostomy or jejunostomy tubes placed over a 10-year period. Ninety-three subjects had a history of pneumonia before feeding tube insertion. Eighty had gastrostomy and 13, jejunostomy…

  8. Aquaculture feed and food safety.

    PubMed

    Tacon, Albert G J; Metian, Marc

    2008-10-01

    The ultimate objective of an aquaculture feed manufacturer and aquaculture food supplier is to ensure that the feed or food produced is both safe and wholesome. Reported food safety risks, which may be associated with the use of commercial animal feeds, including compound aquaculture feeds, usually result from the possible presence of unwanted contaminants, either within the feed ingredients used or from the external contamination of the finished feed on prolonged storage. The major animal feed contaminants that have been reported to date have included Salmonellae, mycotoxins, veterinary drug residues, persistent organic pollutants, agricultural and other chemicals (solvent residues, melamine), heavy metals (mercury, lead, cadmium) and excess mineral salts (hexavalent chromium, arsenic, selenium, flourine), and transmissible spongiform encephalopathies. Apart from the direct negative effect of these possible contaminants on the health of the cultured target species, there is a risk that the feed contaminants may be passed along the food chain, via contaminated aquaculture produce, to consumers. In recent years, public concern regarding food safety has increased as a consequence of the increasing prevalence of antibiotic residues, persistent organic pollutants, and chemicals in farmed seafood. The important role played by the Food and Agriculture Organization of the United Nations (FAO) and the Codex Alimentarius Commission in the development of international standards, guidelines, and recommendations to protect the health of consumers and ensure fair practices in the food trade is discussed. PMID:18991902

  9. Realizing "value-added" metrology

    NASA Astrophysics Data System (ADS)

    Bunday, Benjamin; Lipscomb, Pete; Allgair, John; Patel, Dilip; Caldwell, Mark; Solecky, Eric; Archie, Chas; Morningstar, Jennifer; Rice, Bryan J.; Singh, Bhanwar; Cain, Jason; Emami, Iraj; Banke, Bill, Jr.; Herrera, Alfredo; Ukraintsev, Vladamir; Schlessinger, Jerry; Ritchison, Jeff

    2007-03-01

    The conventional premise that metrology is a "non-value-added necessary evil" is a misleading and dangerous assertion, which must be viewed as obsolete thinking. Many metrology applications are key enablers to traditionally labeled "value-added" processing steps in lithography and etch, such that they can be considered integral parts of the processes. Various key trends in modern, state-of-the-art processing such as optical proximity correction (OPC), design for manufacturability (DFM), and advanced process control (APC) are based, at their hearts, on the assumption of fine-tuned metrology, in terms of uncertainty and accuracy. These trends are vehicles where metrology thus has large opportunities to create value through the engineering of tight and targetable process distributions. Such distributions make possible predictability in speed-sorts and in other parameters, which results in high-end product. Additionally, significant reliance has also been placed on defect metrology to predict, improve, and reduce yield variability. The necessary quality metrology is strongly influenced by not only the choice of equipment, but also the quality application of these tools in a production environment. The ultimate value added by metrology is a result of quality tools run by a quality metrology team using quality practices. This paper will explore the relationships among present and future trends and challenges in metrology, including equipment, key applications, and metrology deployment in the manufacturing flow. Of key importance are metrology personnel, with their expertise, practices, and metrics in achieving and maintaining the required level of metrology performance, including where precision, matching, and accuracy fit into these considerations. The value of metrology will be demonstrated to have shifted to "key enabler of large revenues," debunking the out-of-date premise that metrology is "non-value-added." Examples used will be from critical dimension (CD

  10. Breast feeding: success or failure.

    PubMed

    Houston, M J

    1981-11-01

    Awareness of the important role of breast feeding in child health and the reproductive cycle, which is well documented elsewhere, necessitates an examination of the changing practice of breast feeding. This paper reviews these changing practices both in Western and developing societies, examines the problems which lead to lactation failure, and looks at factors related to success in breast feeding. In the light of the need for practical help for successful breast feeding. the present system of support both in hospital and at home is then discussed. An alternative system of structured home support for post-natal women, which has been shown to increase the success rate of breast feeding, is outlined. The way in which this system acts is discussed and the implications for both mothers and health staff are considered. PMID:6915047

  11. A History of Infant Feeding

    PubMed Central

    Stevens, Emily E; Patrick, Thelma E; Pickler, Rita

    2009-01-01

    The historical evolution of infant feeding includes wet nursing, the feeding bottle, and formula use. Before the invention of bottles and formula, wet nursing was the safest and most common alternative to the natural mother's breastmilk. Society's negative view of wet nursing, combined with improvements of the feeding bottle, the availability of animal's milk, and advances in formula development, gradually led to the substitution of artificial feeding for wet nursing. In addition, the advertising and safety of formula products increased their popularity and use among society. Currently, infant formula-feeding is widely practiced in the United States and appears to contribute to the development of several common childhood illnesses, including atopy, diabetes mellitus, and childhood obesity. PMID:20190854

  12. Missing top of the AdS resonance structure

    NASA Astrophysics Data System (ADS)

    Yang, I.-Sheng

    2015-03-01

    We study a massless scalar field in AdSd +1 with a nonlinear coupling ϕN and not limited to spherical symmetry. The free-field-eigenstate spectrum is strongly resonant, and it is commonly believed that the nonlinear coupling leads to energy transfer between eigenstates. We prove that when N d is even, the most efficient resonant channels to transfer energy are always absent. In particular, for N =3 this means no energy transfer at all. For N =4 , this effectively kills half of the channels, leading to the same set of extra conservation laws recently derived for gravitational interactions within spherical symmetry.

  13. Magnetic mass in 4D AdS gravity

    NASA Astrophysics Data System (ADS)

    Araneda, René; Aros, Rodrigo; Miskovic, Olivera; Olea, Rodrigo

    2016-04-01

    We provide a fully covariant expression for the diffeomorphic charge in four-dimensional anti-de Sitter gravity, when the Gauss-Bonnet and Pontryagin terms are added to the action. The couplings of these topological invariants are such that the Weyl tensor and its dual appear in the on-shell variation of the action and such that the action is stationary for asymptotic (anti-)self-dual solutions in the Weyl tensor. In analogy with Euclidean electromagnetism, whenever the self-duality condition is global, both the action and the total charge are identically vanishing. Therefore, for such configurations, the magnetic mass equals the Ashtekhar-Magnon-Das definition.

  14. Canonical energy and hairy AdS black holes

    NASA Astrophysics Data System (ADS)

    Hyun, Seungjoon; Park, Sang-A.; Yi, Sang-Heon

    2016-08-01

    We propose the modified version of the canonical energy which was introduced originally by Hollands and Wald. Our construction depends only on the Euler-Lagrange expression of the system and thus is independent of the ambiguity in the Lagrangian. After some comments on our construction, we briefly mention on the relevance of our construction to the boundary information metric in the context of the AdS/CFT correspondence. We also study the stability of three-dimensional hairy extremal black holes by using our construction.

  15. Microbial and physicochemical properties of sugarcane bagasse for potential conversion to value-added products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugarcane bagasse is a potential source for commercially-viable products such as animal feed, mulch, or fuel. The applications will be determined by the levels of moisture, ash and beneficial chemicals in the bagasse. Manufacturing value-added products will be impacted by microbes, and may require m...

  16. Updates of the KArLE Experiment: New Libs Calibration Under High Vacuum for the Quantification of Potassium in Basalt for In Situ Geochronology

    NASA Technical Reports Server (NTRS)

    Devismes, D.; Cohen, B. A.; Li, Z.-H.; Miller, J. S.

    2014-01-01

    In planetary exploration, in situ absolute geochronology is one of the main important measurements that needs to be accomplished. Until now, on Mars, the age of the surface is only determined by crater density counting, which gives relative ages. These ages can have a lot of uncertainty as they depend on many parameters. More than that, the curves must be ties to absolute ages. Thus far, only the lost lander Beagle 2 was designed to conduct absolute geochronology measurements, though some recent attempts using MSL Curiosity show that this investigation is feasible and should be strongly encouraged for future flight. Experimental: The Potassium (K)-Argon Laser Experiment (KArLE) is being developed at MSFC through the NASA Planetary Instrument Definition and Development Program (PIDDP). The goal of this experiment is to provide in situ geochronology based on the K-Ar method. A laser ablates a rock under high vacuum, creating a plasma which is sensed by an optical spectrometer to do Laser Induced Breakdown Spectroscopy (LIBS). The ablated material frees gases, including radiogenic 40Ar,which is measured by a mass spectrometer (MS). As the potassium is a content and the 40Ar is a quantity, the ablated mass needed in order to relate them. The mass is given by the product of the ablated volume by the density of this material. So we determine the mineralogy of the ablated material with the LIBS spectra and images and calculate its density. The volume of the pit is measured by using microscopy. LIBS measurement of K under high vacuum: Three independant projects [1, 2, 3] including KArLE, are developing geochronological instruments based on this LA-LIBS-MS method. Despite several differences in their setup, all of them have validated the methods with analyses and ages. However, they all described difficulties with the LIBS measurements of K [3,4]. At ambient pressure, the quantification of K by LIBS on geological materials can be accurate [5]. However the protocol of the LA-LIBS

  17. Feed Structure For Antennas

    NASA Technical Reports Server (NTRS)

    Fink, Patrick W. (Inventor); Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Lin, Greg Y. (Inventor)

    2005-01-01

    A novel feed structure, for an antenna having a resonant electric field structure, comprising a patch element, an integrated circuit attached to the patch element, at least one inner conductor electrically connected to and terminating at the integrated circuit on a first end of the at least one inner conductor, wherein the at least one inner conductor extends through and is not electrically connected to the patch element, and wherein the at least one inner conductor is available for electrical connectivity on a second end of the at least one inner conductor, and an outer conductor electrically connected to and terminating at the patch element on a first end of the outer conductor, wherein the outer conductor is available for electrical connectivity on a second end of the outer conductor, and wherein the outer conductor concentrically surrounds the at least one inner conductor from the second end of the at least one inner conductor available for electrical connectivity to the first end of the outer conductor terminating at the patch element.

  18. Feeding At-Risk Infants and Toddlers.

    ERIC Educational Resources Information Center

    Jaffe, Mata B.

    1989-01-01

    Speech-language pathologists working with infants or toddlers with feeding problems should obtain a feeding history, conduct an assessment of feeding practices, set appropriate preliminary and long-range goals, and investigate treatment options and appropriate feeding techniques. Feeding techniques for premature, neurologically impaired, Down…

  19. Low phytate corn feed reduces swine slurry P content without affecting crop P availability in slurry applied soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traditional corn feed contains phosphorus (P) in a form that monogastric animals such as swine and poultry can not use efficiently. Poor use efficiency of feed P requires P supplements be added to the diet and results in manure having a high P content. Land application of this manure, at rates to me...

  20. Application of the HWVP measurement error model and feed test algorithms to pilot scale feed testing

    SciTech Connect

    Adams, T.L.

    1996-03-01

    The purpose of the feed preparation subsystem in the Hanford Waste Vitrification Plant (HWVP) is to provide, for control of the properties of the slurry that are sent to the melter. The slurry properties are adjusted so that two classes of constraints are satisfied. Processability constraints guarantee that the process conditions required by the melter can be obtained. For example, there are processability constraints associated with electrical conductivity and viscosity. Acceptability constraints guarantee that the processed glass can be safely stored in a repository. An example of an acceptability constraint is the durability of the product glass. The primary control focus for satisfying both processability and acceptability constraints is the composition of the slurry. The primary mechanism for adjusting the composition of the slurry is mixing the waste slurry with frit of known composition. Spent frit from canister decontamination is also recycled by adding it to the melter feed. A number of processes in addition to mixing are used to condition the waste slurry prior to melting, including evaporation and the addition of formic acid. These processes also have an effect on the feed composition.

  1. Behavioral pattern of Rohilkhandi kids under different feeding systems

    PubMed Central

    Kumari, Anjali; Patel, B. H. M.; Maurya, Vipin; Godara, Asu Singh; Verma, Med Ram; Singh, Mukesh

    2016-01-01

    groups. Other minor activities, viz., defecation and urination were negligible. No stereotypic activities were observed. Conclusion: It was concluded that provision of un-chopped fodder in circular feeder could only simulate natural feeding behavior of goat but did not give any added advantage. Further, feeding chopped fodder in linear feeding trough lead to increased consumption and more time is spent on feeding than on agonistic behavior as compared to the other two groups. PMID:27536041

  2. [Drug administration through enteral feeding catheters].

    PubMed

    Goñi Viguria, R; Sánchez Sanz, L; Asiain Erro, M; Baztán Indave, A

    2001-01-01

    Because of easiness and accessibility, the oral route of administration is usually the route of choice for medication delivery, as long as the oral drug form is available and the patients' circumstances allow it.In patients admitted to the intensive care unit this route is frequently altered. This provokes difficulties in swallowing and consequently an enteral feeding catheter must be inserted to supply the patient's nutritional requirements. This catheter is also used for the drug administration, which necessitates opening capsules or crushing pills before dilution. When added to drug-nutrient interactions, this process alters the drug's properties and modifies its pharmacokinetic profile, its pharmacological effect and the intensity of side effects. It can also provoke catheter obstruction. The aim of this study was to establish guidelines for drug administration through enteral feeding catheters. We provide a thorough review of the literature, describe oral drug forms, present a protocol for correct drug administration and provide a guide to the most commonly used drugs in our unit. For each of these drugs we include recommendations on administration and possible alternatives. PMID:11459545

  3. Infant feeding practices in rural Bangladesh.

    PubMed

    Das, D K; Talukder, M Q; Sella, G E

    1992-01-01

    A longitudinal study was done on the infant feeding practices in a rural area. One hundred and ten infants were followed up from birth to 1 year of age by alternate day home visits, to inquire about the type of food, and frequency of consuming it. It was found that 100% mothers breast-fed their infants from birth to 1 year, almost every day. But, bottles containing various kinds of milk and starchy food were added to 60% of infants diets by 3 months, and 80% by 5 months of age. This additional food was given mostly in diluted form, which was more so in case of tinned milk. Family food such as rice and vegetables were given in 30% and 40% child days respectively from 6 months to 1 year. Rural people withhold protein food and fruits during infancy. It is concluded, that infant feeding practices in our population is improper and mothers should, therefore, be trained and motivated on weaning practices for timely and adequate supplementation to ameliorate the presently observed dietary deficiency and early malnutrition in rural Bangladesh. PMID:1459679

  4. Feeding the future.

    PubMed

    Bender, W; Smith, M

    1997-03-01

    This article discusses the unequal distribution of food within and among countries of the world, poverty as the main cause of hunger, the patterns of population growth, and future prospects. The evidence reveals the potential for reaching limits of agricultural expansion. Widespread environmental destruction suggests that agricultural lands are declining. Current production patterns may not be sustainable. "Population growth is the single largest determinant of future needs." Farmers of the world's poorest regions must produce food to meet the needs of a doubled population by 2050. The 1996 World Food Summit urged that agricultural policies emphasize environmentally sustainable production methods and a wider variety of crops that would include sorghum and millet. In the early 1990s, 40% of Africa's population was food-energy deficient. Africa has some of the highest population growth rates. Fertility stands at about 6 children/woman. Even with reduced fertility, the African population is expected to double to 22% of world population by 2050. The East Asian population, which is dominated by China, is expected to reach 2.2 billion by 2050. South Asia includes some of the poorest and most densely populated countries; its population is expected to reach 2.2-3.3 billion by 2050. 43% of the malnourished population during 1990-92 lived in sub-Saharan Africa, 22% lived in South Asia, 16% lived in East and Southeast Asia, 15% lived in Latin America and the Caribbean, and 12% lived in the Near East and North Africa. The proportions of underweight children included 58% in South Asia, 30% in sub-Saharan Africa, 25% in the Near East and North Africa, 24% in East and Southeast Asia, and 12% in Latin America and the Caribbean. If everyone adopted a vegetarian diet and no food were wasted, there would be enough food to feed 10 billion people. Malnourishment has the harshest effects on children, rural populations, the growing urban poor, and victims of natural disasters. PMID

  5. Infant feeding in India.

    PubMed

    1984-09-15

    The report of a survey organized by the Nutrition Foundation of India indicated that, although breastfeeding is the traditional standard of infant nutrition in India, good infant feeding practices depend on education provided by health services. Interviews with 4926 mothers with infants under 1 year indicated that over 97% motherrs suckle their infants, and 75% or more in most centers are still breastfeeding when the infant is 1 year old. At age 5 months 30-40% of infants are fed entirely from the breast; at age 1, 5-10% were getting no other food. Of the very small number of mothers who never breastfed their infants, most belonged to the highest income group. Causes of lactation failure in India and other countries seem to be social and psychological and not physiological. Most Indian babies grow well at first, but by the age of 6 months are growth retarded. Growth retardation may be caused by insufficient breast milk and repeated gastrointestinal and respiratory infections associated with poor hygiene and abject poverty, both more prevalent in Calcutta than in Bombay and Madras. Because of risk of infection, dietary supplements should be given to the mother (rather than to the infant) during the 1st 6 months of lactation. Traditional cow and buffalo milk was the main supplement given to 1955 of infants surveyed, but 1531 were given commerical milk formulas. Commercial milk was used mainly by the wealthy in big cities but some was used in rural areas, where some of the poorest mothers spend 10% of family income on commerical milk. It is important that fresh animal milk be made available to the poor at reasonable prices. Indian mothers are reluctant to give older infants any normal family foods except cereals. Manuals should be prepared for use by health workers to teach practical nutrition education in different regions. PMID:6147646

  6. Infant feeding practices and obesity.

    PubMed

    Himes, J H

    1979-08-01

    Selected assumptions regarding associations between artificial feeding and infantile obesity are examined. Although some artificial baby foods (desserts, meats, egg yolks) have considerably greater caloric density than breast milk, a large class of baby foods and most milks and formulas are comparable to breast milk in caloric density. The intake of infant foods seems to be related more to caloric density than volume. Modern day artificial feeding in developed countries tends to produce larger weight gains than breast feeding, although no good data exist to evaluate the composition of these weight gains. Many more data from well planned studies are needed to fully elucidate possible mechanisms of infantile obesity. PMID:458075

  7. Feeding Tips For Your Baby with CHD

    MedlinePlus

    ... with a combination of breast- and bottle-feeding. Breast-Feeding Your Baby If your baby is diagnosed with ... use too. If your baby needs surgery after breast-feeding has been established, you can pump your breasts ...

  8. Microbiological turbidimetric analysis of low chlortetracycline concentrations in feeds.

    PubMed

    Ragheb, H S; Porubcan, L S

    1975-05-01

    Recovery studies in which chlortetracycline hydrochloride (CTC-HCI) standard was added to cattle and swine feed supplements at 4.09-9.99 g/ton showed lower antibiotic recovery turbidimetrically (80.6-98.7%) than by the AOAC modified standard as in 38.179(d) (91.2-98.7%) and the plain buffer as in 38.179(b) (93.8-133.0%) methods. Three feeds fortified with a commercial premix at the levels of 5.0 and 10.0 g CTC-HCI/ton showed an overall CTC-HCI recovery of 87.6-110.6% by manual turbidimetric assay. Results were 89.1-108.7% by the AOAC inactivated feed diluent standard and 95.4-125.4% by the plain buffer methods. For some sample extracts (as in cattle feed) the use of heat to stop bacterial growth in the turbidimetric method caused formation of a precipitate. Cooling of cultures to room temperature and rapid reading of sample turbidity followed by standard curve concentrations minimized this interference. The manual turbidimetric assay of low levels of CTC-HCI in feeds appears to offer advantages over other methods. PMID:1141190

  9. The inside outs of AdS3/CFT2: exact AdS wormholes with entangled CFT duals

    NASA Astrophysics Data System (ADS)

    Mandal, Gautam; Sinha, Ritam; Sorokhaibam, Nilakash

    2015-01-01

    We present the complete family of solutions of 3D gravity (Λ < 0) with two asymptotically AdS exterior regions. The solutions are constructed from data at the two boundaries, which correspond to two independent and arbitrary stress tensors T R , , and T L , . The two exteriors are smoothly joined on to an interior region through a regular horizon. We find CFT duals of these geometries which are entangled states of two CFT's. We compute correlators between general operators at the two boundaries and find perfect agreement between CFT and bulk calculations. We calculate and match the CFT entanglement entropy (EE) with the holographic EE which involves geodesics passing through the wormhole. We also compute a holographic, non-equilibrium entropy for the CFT using properties of the regular horizon. The construction of the bulk solutions here uses an exact version of Brown-Henneaux type diffeomorphisms which are asymptotically nontrivial and transform the CFT states by two independent unitary operators on the two sides. Our solutions provide an infinite family of explicit examples of the ER=EPR relation of Maldacena and Susskind [1].

  10. Knowledge, attitudes and practice regarding infant feeding among mother substitutes.

    PubMed

    Jethi, S C; Shrivastava, D K

    1987-10-01

    With more women entering the workforce, the issue of infant nutrition has become more complex. Mother surrogates, or substitutes, are increasingly taking over the responsibility of infant care. 80 mother substitutes, aged 7-70, were interviewed in Jabalpur town, India, from October 1983-July 1984. Substitutes originated from nuclear families consisting of grandmothers, aunts, elder sisters, brothers, and servants. They were questioned concerning breast feeding, top milk initiation, feeding technique, and weaning. Results pointed to a variety of opinions on feeding practices and nutrition. 50% of younger mother substitutes and the majority of older, uneducated ones believed in initiating breast feeding from the 2nd day onward. 50% of young and 64% of older substitutes did not consider giving colostrum, and various reasons why are cited. 20% of all and 42% of highly educated substitutes were aware of the advantages of breast feeding. 65% of young and 60% uneducated did not know age of initiation of top milk. 45% advocated bottle feeding, with 25% preferring spoon feeding. With regard to "tinned milk" 40% did not use it, 25% were unaware of it, and of 30% using tinned milk, only 1/3 knew the correct technique of reconstitution. The majority of young and uneducated substitutes thought proper weaning age to be after 6 months. 50%, aged 21-40 years, believed in adding solid food from below 6 months. 90% of the young mother substitutes were against solids being introduced by the age of 4 months. A majority of the substitutes suggested weaning foods such as dal, rice, roti, and biscuits with a few considering tinned cereals as proper weaning foods. This response may point to the reason why protein and energy deficiency may be observed around weaning age in many infants throughout the 3rd world. PMID:3448014

  11. Banana meal for feeding pigs: digestive utilization, growth performance and feeding behavior.

    PubMed

    Renaudeau, D; Brochain, J; Giorgi, M; Bocage, B; Hery, M; Crantor, E; Marie-Magdeleine, C; Archimède, H

    2014-04-01

    The main objective of the present work was to determine the nutritional value and the strategies of using green banana meal (BM) in growing pigs. Two trials involving a total of 96 growing pigs were designed to study the effect of the harvest stage on the nutritional and energy values of BM (trial 1) and to evaluate the consequence of feeding gradual levels of BM on growth performance and feeding behavior in growing pigs (trial 2). In trial 1, the digestive utilization of three diets including 40% BM were compared with a control (C) soybean meal-corn diet in two batches of 12 pigs. BM was obtained from fruits harvested at 750 degrees-days (DD; early harvesting stage), 900 DD (normal harvesting stage) and 1150 DD (late harvesting stage). In trial 2, 72 Large White pigs were grouped in pens of nine animals and were given ad libitum access to one of the four dietary treatments (two pens/diet) differing from the rate of inclusion of 900 DD BM (0%, 20%, 40%, 60%). The estimated energy apparent digestibility coefficients of BM increased with the harvest stage (75.5%, 80.7% and 83.2% for BM at 750, 900 and 1150 DD, respectively). Digestible energy and metabolizable energy values were higher for BM at 1150 DD (13.56 and 13.05 MJ/kg DM, respectively) than at 900 DD (13.11 and 12.75 MJ/kg DM, respectively) or at 750 DD (12.00 and 11.75 MJ/kg DM, respectively). In trial 2, average daily gain and feed conversion ratio were not affected (P>0.05) by the rate of BM inclusion (822 g/day and 2.75 kg/kg on average, respectively). Feed intake and feeding behavior parameters were not significantly influenced by the dietary treatments except for the rate of feed ingestion with a lower value for the diet with 40% of BM (27.4 v. 32.2 g/min on average; P<0.01) when compared with the other diets. Results of this study indicate that the energy value of BM increases with the harvest stage and that BM can be incorporated up to 60% in growing finishing pig diets. PMID:24528838

  12. Calibration of the Fluorine, Chlorine and Hydrogen Content of Apatites With the ChemCam LIBS Instrument

    NASA Technical Reports Server (NTRS)

    Meslin, P.-Y.; Cicutto, L.; Forni, O.; Drouet, C.; Rapin, W.; Nachon, M.; Cousin, A.; Blank, J. G.; McCubbin, F. M.; Gasnault, O.; Newsom, H.; Mangold, N.; Schroeder, S.; Sautter, V.; Maurice, S.; Wiens, R. C.

    2016-01-01

    Determining the composition of apatites is important to understand the behavior of volatiles during planetary differentiation. Apatite is an ubiquitous magmatic mineral in the SNC meteorites. It is a significant reservoir of halogens in these meteorites and has been used to estimate the halogen budget of Mars. Apatites have been identified in sandstones and pebbles at Gale crater by ChemCam, a Laser-Induced Breakdown Spectroscometer (LIBS) instrument onboard the Curiosity rover. Their presence was inferred from correlations between calcium, fluorine (using the CaF molecular band centered near 603 nm, whose detection limit is much lower that atomic or ionic lines and, in some cases, phosphorus (whose detection limit is much larger). An initial quantification of fluorine, based on fluorite (CaF2)/basalt mixtures and obtained at the LANL laboratory, indicated that the excess of F/Ca (compared to the stoichiometry of pure fluorapatites) found on Mars in some cases could be explained by the presence of fluorite. Chlorine was not detected in these targets, at least above a detection limit of 0.6 wt% estimated from. Fluorapatite was later also detected by X-ray diffraction (with CheMin) at a level of approx.1wt% in the Windjana drill sample (Kimberley area), and several points analyzed by ChemCam in this area also revealed a correlation between Ca and F. The in situ detection of F-rich, Cl-poor apatites contrasts with the Cl-rich, F-poor compositions of apatites found in basaltic shergottites and in gabbroic clasts from the martian meteorite NWA 7034, which were also found to be more Cl-rich than apatites from basalts on Earth, the Moon, or Vesta. The in situ observations could call into question one of the few possible explanations brought forward to explain the SNC results, namely that Mars may be highly depleted in fluorine. The purpose of the present study is to refine the calibration of the F, Cl, OH and P signals measured by the ChemCam LIBS instrument, initiated

  13. Feeding cotton products to cattle.

    PubMed

    Rogers, Glenn M; Poore, Matthew H; Paschal, Joe C

    2002-07-01

    Despite the potential for gossypol toxicosis (particularly in pre-ruminants) and risk factors associated with impaired fertility in bulls, cottonseed products offer a safe alternative feed for cattle producers when fed at recommended levels. Beef producers seeking to lower production costs should consider using cotton byproducts in their feeding programs. If carefully incorporated, cotton byproduct feeds can reduce feed costs while maintaining or increasing the level of cattle performance. Cottonseed meal will remain a standard protein supplement for beef cattle throughout the country. Whole cottonseed has much potential for Southern producers near cotton gins if it is purchased in a timely fashion and fed according to recommendations. Cotton gin trash, cottonseed hulls, and cotton textile mill waste also have potential economic benefits, especially to producers located near cotton and cottonseed processing facilities. PMID:12235661

  14. Breast feeding pattern in neonates.

    PubMed

    Srivastava, S P; Sharma, V K; Kumar, V

    1994-09-01

    The present study comprised 100 mothers of newborn babies with regard to their belief and practices about lactation. A vast majority (98.2%) of the mothers were breast feeding, 87.9% mothers used prelacteal feeds of one sort or the other. Only 0.5% breast fed their babies within 6 hours and nearly 50% started after 48 hours. Colostrum was discarded by 82.9% of mother and nearly 73% wanted to continue breast feeding beyond 1 year. The age of weaning preferred was after 1 year by 91%. Only 24.7% mothers had undergone antenatal check ups. Hence, much needs to be done with regards to proper antenatal care and advice to discourage wrong and harmful feeding practices. PMID:7883365

  15. Rotary powder feed through apparatus

    DOEpatents

    Lewis, Gary K.; Less, Richard M.

    2001-01-01

    A device for increasing the uniformity of solids within a solids fabrication system, such as a direct light fabrication (DLF) system in which gas entrained powders are passed through the focal point of a moving high-power light which fuses the particles in the powder to a surface being built up in layers. The invention provides a feed through interface wherein gas entrained powders input from stationary input lines are coupled to a rotating head of the fabrication system. The invention eliminates the need to provide additional slack in the feed lines to accommodate head rotation, and therefore reduces feed line bending movements which induce non-uniform feeding of gas entrained powder to a rotating head.

  16. Animal feed compositions containing phytase derived from transgenic alfalfa and methods of use thereof

    DOEpatents

    Austin-Phillips, Sandra; Koegel, Richard G.; Straub, Richard J.; Cook, Mark

    2001-01-01

    A value-added composition of matter containing plant matter from transgenic alfalfa which expresses exogenous phytase activity is disclosed. The phytase activity is a gene product of an exogenous gene encoding for phytase which has been stably incorporated into the genome of alfalfa plants. The transgenic alfalfa expresses phytase activity in nutritionally-significant amounts, thereby enabling its use in animal feeds to eliminate the need for phosphorous supplementation of livestock, poultry, and fish feed rations.

  17. Animal feed compositions containing phytase derived from transgenic alfalfa and methods of use thereof

    DOEpatents

    Austin-Phillips, Sandra; Koegel, Richard G.; Straub, Richard J.; Cook, Mark

    1999-01-01

    A value-added composition of matter containing plant matter from transgenic alfalfa which expresses exogenous phytase activity is disclosed. The phytase activity is a gene product of an exogenous gene encoding for phytase which has been stably incorporated into the genome of alfalfa plants. The transgenic alfalfa expresses phytase activity in nutritionally-significant amounts, thereby enabling its use in animal feeds to eliminate the need for phosphorous supplementation of livestock, poultry, and fish feed rations.

  18. Kinetics of the transient optical absorption in Li2B4O7 and LiB3O5 lithium borate crystals

    NASA Astrophysics Data System (ADS)

    Ogorodnikov, I. N.; Kiseleva, M. S.

    2012-04-01

    This paper reports on a study of the kinetics of electron tunneling transport between electron and hole centers in Li2B4O7 and LiB3O5 lithium borate crystals under the conditions where the mobility of one of the partners in the recombination process is thermally stimulated. A mathematical model has been proposed to describe all specific features in the relaxation kinetics of the induced optical density observed in Li2B4O7 (LTB) and LiB3O5 (LBO) nonlinear optical crystals within a broad time interval of 10-8-1 s after a radiation pulse. The results of calculations have been compared with experimental data on transient optical absorption (TOA) of LTB and LBO crystals in the visible and ultraviolet spectral regions. The nature of the radiation defects responsible for TOA and the dependence of the TOA decay kinetics on temperature, excitation power, and other experimental conditions have been discussed.

  19. An assessment of the potential of laser-induced breakdown spectroscopy (LIBS) for the analysis of cesium in liquid samples of biological origin.

    PubMed

    Metzinger, Anikó; Kovács-Széles, Eva; Almási, István; Galbács, Gábor

    2014-01-01

    The present study describes the development of an analytical method for the determination of cesium in biological fluid samples (human urine and blood samples) by laser-induced breakdown spectroscopy (LIBS). The developed method is based on sample presentation by liquid-to-solid conversion, enhancing the emission signal by drying the liquid into small "pockets" created in a metal support (zinc plate), and allows the analysis to be carried out on as little as 1 μL of sample volume, in a closed sample cell. Absolute detection limits on the Cs I 852.1 nm spectral line were calculated by the IUPAC 3σ method to be 6 ng in the urine sample and 27 ng in the blood serum sample. It is estimated that LIBS may be used to detect highly elevated concentration levels of Cs in fluid samples taken from people potentially exposed to surges of Cs from non-natural sources. PMID:25014845

  20. Storage and feeding of coal

    NASA Technical Reports Server (NTRS)

    Jenike, A. W.; Carson, J. W.

    1977-01-01

    Reliable feeding of coal from storage bins to process requires the knowledge of the behavior of coal during flow. The study of the flow of bulk solids was undertaken in the 1950's and led to the development of flow ability testing equipment and of the Mass Flow concept of design for reliable flow. The theory has since been expanded to two-phase, solids-gas system, and has found world wide application in the design of storage and feeding systems.

  1. GenoLIB: a database of biological parts derived from a library of common plasmid features.

    PubMed

    Adames, Neil R; Wilson, Mandy L; Fang, Gang; Lux, Matthew W; Glick, Benjamin S; Peccoud, Jean

    2015-05-26

    Synthetic biologists rely on databases of biological parts to design genetic devices and systems. The sequences and descriptions of genetic parts are often derived from features of previously described plasmids using ad hoc, error-prone and time-consuming curation processes because existing databases of plasmids and features are loosely organized. These databases often lack consistency in the way they identify and describe sequences. Furthermore, legacy bioinformatics file formats like GenBank do not provide enough information about the purpose of features. We have analyzed the annotations of a library of ∼2000 widely used plasmids to build a non-redundant database of plasmid features. We looked at the variability of plasmid features, their usage statistics and their distributions by feature type. We segmented the plasmid features by expression hosts. We derived a library of biological parts from the database of plasmid features. The library was formatted using the Synthetic Biology Open Language, an emerging standard developed to better organize libraries of genetic parts to facilitate synthetic biology workflows. As proof, the library was converted into GenoCAD grammar files to allow users to import and customize the library based on the needs of their research projects. PMID:25925571

  2. GenoLIB: a database of biological parts derived from a library of common plasmid features

    PubMed Central

    Adames, Neil R.; Wilson, Mandy L.; Fang, Gang; Lux, Matthew W.; Glick, Benjamin S.; Peccoud, Jean

    2015-01-01

    Synthetic biologists rely on databases of biological parts to design genetic devices and systems. The sequences and descriptions of genetic parts are often derived from features of previously described plasmids using ad hoc, error-prone and time-consuming curation processes because existing databases of plasmids and features are loosely organized. These databases often lack consistency in the way they identify and describe sequences. Furthermore, legacy bioinformatics file formats like GenBank do not provide enough information about the purpose of features. We have analyzed the annotations of a library of ∼2000 widely used plasmids to build a non-redundant database of plasmid features. We looked at the variability of plasmid features, their usage statistics and their distributions by feature type. We segmented the plasmid features by expression hosts. We derived a library of biological parts from the database of plasmid features. The library was formatted using the Synthetic Biology Open Language, an emerging standard developed to better organize libraries of genetic parts to facilitate synthetic biology workflows. As proof, the library was converted into GenoCAD grammar files to allow users to import and customize the library based on the needs of their research projects. PMID:25925571

  3. Feeding the Monster

    NASA Astrophysics Data System (ADS)

    2005-10-01

    Near-infrared images of the active galaxy NGC 1097, obtained with the NACO adaptive optics instrument on ESO's Very Large Telescope, disclose with unprecedented detail a complex central network of filamentary structure spiralling down to the centre of the galaxy. These observations provide astronomers with new insights on how super-massive black holes lurking inside galaxies get fed. "This is possibly the first time that a detailed view of the channelling process of matter, from the main part of the galaxy down to the very end in the nucleus is released," says Almudena Prieto (Max-Planck Institute, Heidelberg, Germany), lead author of the paper describing these results. Located at a distance of about 45 million light-years in the southern constellation Fornax (the Furnace), NGC 1097 is a relatively bright, barred spiral galaxy seen face-on. At magnitude 9.5, and thus just 25 times fainter than the faintest object that can be seen with the unaided eye, it appears in small telescopes as a bright, circular disc. NGC 1097 is a very moderate example of an Active Galactic Nucleus (AGN), whose emission is thought to arise from matter (gas and stars) falling into oblivion in a central black hole. However, NGC 1097 possesses a comparatively faint nucleus only, and the black hole in its centre must be on a very strict "diet": only a small amount of gas and stars is apparently being swallowed by the black hole at any given moment. Astronomers have been trying to understand for a long time how the matter is "gulped" down towards the black hole. Watching directly the feeding process requires very high spatial resolution at the centre of galaxies. This can be achieved by means of interferometry as was done with the VLTI MIDI instrument on the central parts of another AGN, NGC 1068 (see ESO PR 17/03), or with adaptive optics [1]. Thus, astronomers [2] obtained images of NGC 1097 with the adaptive optics NACO instrument attached to Yepun, the fourth Unit Telescope of ESO's VLT

  4. Motor control of fly feeding.

    PubMed

    McKellar, Claire E

    2016-06-01

    Following considerable progress on the molecular and cellular basis of taste perception in fly sensory neurons, the time is now ripe to explore how taste information, integrated with hunger and satiety, undergo a sensorimotor transformation to lead to the motor actions of feeding behavior. I examine what is known of feeding circuitry in adult flies from more than 250 years of work in larger flies and from newer work in Drosophila. I review the anatomy of the proboscis, its muscles and their functions (where known), its motor neurons, interneurons known to receive taste inputs, interneurons that diverge from taste circuitry to provide information to other circuits, interneurons from other circuits that converge on feeding circuits, proprioceptors that influence the motor control of feeding, and sites of integration of hunger and satiety on feeding circuits. In spite of the several neuron types now known, a connected pathway from taste inputs to feeding motor outputs has yet to be found. We are on the threshold of an era where these individual components will be assembled into circuits, revealing how nervous system architecture leads to the control of behavior. PMID:27309215

  5. Evaluation of a compact spectrograph/detection system for a LIBS instrument for in-situ and stand-off detection

    SciTech Connect

    Salle B.; Cremers, D. A.; Benelli, K. M.; Busse, J. R.; Wiens, R. C.; Maurice, S.; Walters, R. A.

    2004-01-01

    Laser-induced breakdown spectroscopy (LIBS) is a method of determining the elemental composition of a material at in-situ or stand-off distances. The information content of the plasma is high. For this reason, LIBS is being developed for instruments to planet surfaces. Each laser plasma generates a light signal containing a high density of information regarding the elemental components of the target material. The useful spectral range of the emitted light extends from the vacuum ultraviolet ({approx} 120 nm) out to 850 nm. Within these extreme are strong emission features from all elements useful to identify the element in the target and also to perform quantitative analysis. The detection system (spectrograph and detector) used to process the plasma light determine sthe quality and quantity of the data gathered. The processing of the collected plasma light by the spectrograph and detector includes (1) spectral dispersion of the light, (2) recording the spectrally resolved light signal and (3) converting the photonic information to digital form. The characteristics of these two components are crucial to the performance of a LIBS instrument. Spectrographs and detection systems being considered by us for a LIBS flight instrument include a very compact grating type spectrograph integrated in a single package with a CCD detector. An example is the commercially-available Ocean Optics HR2000 spectrograph. This system provides spectral coverage over a fixed limited range with a certain spectral resolution. For such a system, the trade off is between spectral coverage and resolution. Additional units may be used, however, to monitor simultaneously other spectral ranges. A second type of detection system under consideration is an echelle spectrography with a 2-dimensional array detector. Inherently, this system provides complete spectral coverage with the resolution being determined by the size of the spectrography and pixel spacing of the detector array. Both systems are

  6. Direct spectral analysis of tea samples using 266 nm UV pulsed laser-induced breakdown spectroscopy and cross validation of LIBS results with ICP-MS.

    PubMed

    Gondal, M A; Habibullah, Y B; Baig, Umair; Oloore, L E

    2016-05-15

    Tea is one of the most common and popular beverages spanning vast array of cultures all over the world. The main nutritional benefits of drinking tea are its anti-oxidant properties, presumed protection against certain cancers, inhibition of inflammation and possible protective effects against diabetes. Laser induced breakdown spectrometer (LIBS) was assembled as a powerful tool for qualitative and quantitative analysis of various brands of tea samples using 266 nm pulsed UV laser. LIBS spectra for six brands of tea samples in the wavelength range of 200-900 nm was recorded and all elements present in our tea samples were identified. The major toxic elements detected in several brands of tea samples were bromine, chromium and minerals like iron, calcium, potassium and silicon. The spectral assignment was conducted prior to the determination of concentration of each element. For quantitative analysis, calibration curves were drawn for each element using standard samples prepared in known concentration in the tea matrix. The plasma parameters (electron temperature and electron density) were also determined prior to the tea samples spectroscopic analysis. The concentration of iron, chromium, potassium, bromine, copper, silicon and calcium detected in all tea samples was between 378-656, 96-124, 1421-6785, 99-1476, 17-36, 2-11 and 92-130 mg L(-1) respectively. The limits of detection estimated for Fe, Cr, K, Br, Cu, Si, Ca in tea samples were 22, 12, 14, 11, 6, 1 and 12 mg L(-1) respectively. To further confirm the accuracy of our LIBS results, we determined the concentration of each element present in tea samples by using standard analytical technique like ICP-MS. The concentrations detected with our LIBS system are in excellent agreement with ICP-MS results. The system assembled for spectral analysis in this work could be highly applicable for testing the quality and purity of food and also pharmaceuticals products. PMID:26992530

  7. Enhancement of laser-induced breakdown spectroscopy (LIBS) Detection limit using a low-pressure and short-pulse laser-induced plasma process.

    PubMed

    Wang, Zhen Zhen; Deguchi, Yoshihiro; Kuwahara, Masakazu; Yan, Jun Jie; Liu, Ji Ping

    2013-11-01

    Laser-induced breakdown spectroscopy (LIBS) technology is an appealing technique compared with many other types of elemental analysis because of the fast response, high sensitivity, real-time, and noncontact features. One of the challenging targets of LIBS is the enhancement of the detection limit. In this study, the detection limit of gas-phase LIBS analysis has been improved by controlling the pressure and laser pulse width. In order to verify this method, low-pressure gas plasma was induced using nanosecond and picosecond lasers. The method was applied to the detection of Hg. The emission intensity ratio of the Hg atom to NO (IHg/INO) was analyzed to evaluate the LIBS detection limit because the NO emission (interference signal) was formed during the plasma generation and cooling process of N2 and O2 in the air. It was demonstrated that the enhancement of IHg/INO arose by decreasing the pressure to a few kilopascals, and the IHg/INO of the picosecond breakdown was always much higher than that of the nanosecond breakdown at low buffer gas pressure. Enhancement of IHg/INO increased more than 10 times at 700 Pa using picosecond laser with 35 ps pulse width. The detection limit was enhanced to 0.03 ppm (parts per million). We also saw that the spectra from the center and edge parts of plasma showed different features. Comparing the central spectra with the edge spectra, IHg/INO of the edge spectra was higher than that of the central spectra using the picosecond laser breakdown process. PMID:24160875

  8. Recent advances in the use of laser-induced breakdown spectroscopy (LIBS) as a rapid point-of-care pathogen diagnostic

    NASA Astrophysics Data System (ADS)

    Rehse, Steven J.; Miziolek, Andrzej W.

    2012-06-01

    Laser-induced breakdown spectroscopy (LIBS) has made tremendous progress in becoming a viable technology for rapid bacterial pathogen detection and identification. The significant advantages of LIBS include speed (< 1 sec analysis), portability, robustness, lack of consumables, little to no need for sample preparation, lack of genetic amplification, and the ability to identify all bacterial pathogens without bias (including spore-forms and viable but nonculturable specimens). In this manuscript, we present the latest advances achieved in LIBS-based bacterial sensing including the ability to uniquely identify species from more than five bacterial genera with high-sensitivity and specificity. Bacterial identifications are completely unaffected by environment, nutrition media, or state of growth and accurate diagnoses can be made on autoclaved or UV-irradiated specimens. Efficient discrimination of bacteria at the strain level has been demonstrated. A rapid urinary tract infection diagnosis has been simulated with no sample preparation and a one second diagnosis of a pathogen surrogate has been demonstrated using advanced chemometric analysis with a simple "stop-light" user interface. Stand-off bacterial identification at a 20-m distance has been demonstrated on a field-portable instrument. This technology could be implemented in doctors' offices, clinics, or hospital laboratories for point-of-care medical specimen analysis; mounted on military medical robotic platforms for in-the- field diagnostics; or used in stand-off configuration for remote sensing and detection.

  9. LIBS-based detection of As, Br, C, Cl, P, And S in the VUV spectral region in a Mars atmosphere.

    SciTech Connect

    Radziemski, Leon J.,; Cremers, D. A.; Benelli, K. M.; Khoo, C.; Harris, R. D.

    2005-01-01

    Several elements important to planetary geology (e.g. Br, C, Cl, P, S) and the human exploration of Mars (e.g. toxic elements such as As) have strong emission lines in the purge and vacuum ultraviolet (VUV) spectral region (100 to 200 nm). This spectral region has not been extensively studied using geological samples. Prior LIBS work by others examined sulfide mineral indentification and Cl/C and Br/C ratio determinations in organic materials. We studied emissions from the LIBS plasma in this region using a sample chamber filled with 7 torr (930 Pa) of CO{sub 2} to simulate the Martian atmosphere. Lower pressures were also used to evaluate the effect of residual CO{sub 2} on the spectra. The effects of time delay and laser energy on LIBS detection at reduced pressure were examined. The effect of ambient CO{sub 2} on the detection of C in soil was also evaluated. Lines useful for the spectrochemical analysis of As, Br, C, Cl, P, and S were determined, calibration curves prepared, and limits of detection determined for these elements. The experiments reported here were aimed at in-situ (closeup) analysis rather than stand-off detection at many meters.

  10. Examination of the capability of the laser-induced breakdown spectroscopy (LIBS) technique as the emerging laser-based analytical tool for analyzing trace elements in coal

    NASA Astrophysics Data System (ADS)

    Idris, N.; Ramli, M.; Mahidin, Hedwig, R.; Lie, Z. S.; Kurniawan, K. H.

    2014-09-01

    Due to its superior advantageous over the conventional analytical tools, laser-induced breakdown spectroscopy (LIBS) technique nowadays is becoming an emerging analytical tools and it is expected to be new future super star of analytical tool. This technique is based on the use of optical emission from the laser-induced plasma for analyzing spectrochemically the constituent and content of the sampled object. The capability of this technique is examined on analysis of trace elements in coal sample. Coal is one difficult sample to analyze due to its complex chemical composition and physical properties. It is inherent that coal contains trace element including heavy metal, thus mining, beneficiation and utilization poses hazard to environment and to human beings. The LIBS apparatus used was composed by a laser system (Nd-YAG: Quanta Ray; LAB SERIES; 1,064 nm; 500 mJ; 8 ns) and optical detector (McPherson model 2061; 1,000 mm focal length; f/8.6 Czerny-Turner) equipped with Andor I*Star intensified CCD 1024×256 pixels. The emitted laser was focused onto coal sample with a focusing lens of +250 mm. The plasma emission was collected by a fiber optics and sent to the the spectrograph. The coal samples were taken from Province of Aceh. As the results, several trace elements including heavy metal (As, Mn, Pb) can surely be observed, implying the eventuality of LIBS technique to analysis the presence of trace element in coal.

  11. Evaluation of elemental profiling methods, including laser-induced breakdown spectroscopy (LIBS), for the differentiation of Cannabis plant material grown in different nutrient solutions.

    PubMed

    El-Deftar, Moteaa M; Robertson, James; Foster, Simon; Lennard, Chris

    2015-06-01

    Laser-induced breakdown spectroscopy (LIBS) is an emerging atomic emission based solid sampling technique that has many potential forensic applications. In this study, the analytical performance of LIBS, as well as that of inductively coupled plasma mass spectrometry (ICP-MS), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and X-ray microfluorescence (μXRF), was evaluated for the ability to conduct elemental analyses on Cannabis plant material, with a specific investigation of the possible links between hydroponic nutrients and elemental profiles from associated plant material. No such study has been previously published in the literature. Good correlation among the four techniques was observed when the concentrations or peak areas of the elements of interest were monitored. For Cannabis samples collected at the same growth time, the elemental profiles could be related to the use of particular commercial nutrients. In addition, the study demonstrated that ICP-MS, LA-ICP-MS and LIBS are suitable techniques for the comparison of Cannabis samples from different sources, with high discriminating powers being achieved. On the other hand, μXRF method was not suitable for the discrimination of Cannabis samples originating from different growth nutrients. PMID:25898182

  12. The effects of feeding increasing concentrations of corn oil on energy metabolism and nutrient balance in finishing beef steers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of added fat source is common in high-concentrate finishing diets. The objective of our experiment was to determine if feeding increasing concentrations of added dietary corn oil would decrease enteric methane production, increase the ME:DE ratio, and improve retained energy in finishing be...

  13. Detecteur multibandes libs a base de reseaux holographiques epais: Conception optomecanique et gestion de l'innovation

    NASA Astrophysics Data System (ADS)

    Gagnon, Daniel

    Detection of sulfur by optical emission spectroscopy generally presents difficulties because the strongest lines are in the vacuum ultraviolet and therefore are readily absorbed by oxygen molecules in air. A novel concept for a low cost and efficient system to detect sulfur using near infrared lines by Laser-Induced Breakdown Spectroscopy is proposed in this thesis. The concept proposes to use customized thick holographic gratings, also referred as Volume Bragg Grating, for spectral filtering of the plasma light, and built-in custom electronics that amplify and integrate photodiodes output signals. In this work, the optomechanical design, manufacturing and trials of a multiband sensor's prototype is reviewed. Preliminary results has been presented at NASLIBS 2011 and showed a limit of detection comparable to that of a conventional high-end system. An article describing the concept and results has been published in a special issue of the Applied Optics journal. To turn this newly patented concept into commercial success, the management of the innovation has been performed by proposing strategic and tactic alliances for commercialisation purposes applied to strategic business positioning structured along the 3 axis Technology -- Product -- Market. Open innovation is here acting as the paradigm to efficiently reach the market. Discussion relative to strategic and tactic alliance is actually taking place for deployment of the LIBS multiband sensor in the mining industry.

  14. Selection of endophytic fungi from comfrey (Symphytum officinale L.) for in vitro biological control of the phytopathogen Sclerotinia sclerotiorum (Lib.).

    PubMed

    Rocha, Rafaeli; da Luz, Daniela Eleutério; Engels, Cibelle; Pileggi, Sônia Alvim Veiga; de Souza Jaccoud Filho, David; Matiello, Rodrigo Rodrigues; Pileggi, Marcos

    2009-01-01

    Biological control consists of using one organism to attack another that may cause economic damage to crops. Integrated Pest Management (IPM) is a very common strategy. The white mold produced by Sclerotinia sclerotiorum (Lib.) causes considerable damage to bean crops. This fungus is a soil inhabitant, the symptoms of which are characterized by water-soaked lesions covered by a white cottony fungal growth on the soil surface and/or the host plant. Possible biological control agents taken from plants are being investigated as phytopathogen inhibitors. These are endophytic microorganisms that inhabit the intercellular spaces of vegetal tissues and are often responsible for antimicrobial production. The objective of the present study was to select endophytic fungi isolated from comfrey (Symphytum officinale L.) leaves with in vitro antagonist potential against the phytopathogenic fungus S. sclerotiorum. Twelve isolates of endophytic fungi and a pathogenic strain of S. sclerotiorum were used in the challenge method. With the aid of this method, four endophytes with the best antagonistic activity against S. sclerotiorum were selected. Pathogen growth inhibition zones were considered indicative of antibiosis. The percentages of pathogenic mycelia growth were measured both with and without the antagonist, resulting in growth reductions of 46.7% to 50.0% for S. sclerotiorum. These analyses were performed by evaluating the endophytic/pathogenic mycelia growth in mm/day over an eight-day period of antagonistic tests. PMID:24031320

  15. Identification of point defects responsible for laser-induced ultraviolet absorption in LiB3O5 (LBO) crystals

    NASA Astrophysics Data System (ADS)

    Hong, W.; Garces, Nelson Y.; Chirila, M. M.; Halliburton, Larry E.

    2003-05-01

    Electron paramagnetic resonance (EPR) has been used to identify and characterize point defects in lithium triborate (LiB3O5) crystals grown for nonlinear optical applications. As-grown crystals contain oxygen vacancies and lithium vacancies (as well as trace amounts of transition-metal ions in a few samples). Exposing a crystal to ionizing radiation at 77 K produces "free" electrons and holes. These electrons are trapped at the pre-existing oxygen vacancies and give rise to an EPR signal with a large hyperfine from one 11B nucleus. The corresponding holes become self-trapped on oxygen ions as a result of the significant lattice relaxation of a nearest-neighbor fourfold-bonded boron ion. This gives rise to an EPR signal with a smaller 11B hyperfine pattern due to the oxygen"s threefold bonded boron neighbor. Warming the crystal to approximately 130 K destroys the self-trapped hole centers that were initially formed, and allows a second holelike signal to be observed (which in turn decays between 150 and 200 K). The structure of the second hole center is very similar to the self-trapped hole center and a neighboring lithium vacancy makes this latter center more thermally stable. The EPR spectra from Ni+ and Cu2+ ions are also reported.

  16. Reinvestigation on the phase transition of a LiB3O5 crystal near its melting point

    NASA Astrophysics Data System (ADS)

    Wan, S. M.; Zheng, G. M.; Feng, D. X.; Yao, Y. N.; Zhao, Y.; You, J. L.; Hu, Z. G.

    2016-02-01

    Raman spectroscopy has been applied to investigate in-situ the phase transition of a LBO (LiB3O5) crystal near its melting point in order to explain the discrepancies between the experimental results observed in the LBO crystal growth process and the predicted results obtained from the Li2O-B2O3 phase diagram. When the LBO crystal begins to melt, it first decomposes to the kinetic products Li2B4O7 and B2O3; then the Li2B4O7 reacts with the undecomposed LBO to form the thermodynamic product Li3B7O12. On the basis of these results, a set of models have been proposed to describe the structural transformations present in the phase transition. Additionally, our experimental result indicates that Li3B7O12 is stable/metastable at room temperature. Its Raman spectrum has been calculated by the density functional theory method for identification of the Li3B7O12 crystalline phase in a mixture. The result shows that Li3B7O12 has three strong characteristic Raman peaks located around 595, 775 and 1040 cm-1.

  17. Selection of endophytic fungi from comfrey (Symphytum officinale L.) for in vitro biological control of the phytopathogen Sclerotinia sclerotiorum (Lib.)

    PubMed Central

    Rocha, Rafaeli; da Luz, Daniela Eleutério; Engels, Cibelle; Pileggi, Sônia Alvim Veiga; de Souza Jaccoud Filho, David; Matiello, Rodrigo Rodrigues; Pileggi, Marcos

    2009-01-01

    Biological control consists of using one organism to attack another that may cause economic damage to crops. Integrated Pest Management (IPM) is a very common strategy. The white mold produced by Sclerotinia sclerotiorum (Lib.) causes considerable damage to bean crops. This fungus is a soil inhabitant, the symptoms of which are characterized by water-soaked lesions covered by a white cottony fungal growth on the soil surface and/or the host plant. Possible biological control agents taken from plants are being investigated as phytopathogen inhibitors. These are endophytic microorganisms that inhabit the intercellular spaces of vegetal tissues and are often responsible for antimicrobial production. The objective of the present study was to select endophytic fungi isolated from comfrey (Symphytum officinale L.) leaves with in vitro antagonist potential against the phytopathogenic fungus S. sclerotiorum. Twelve isolates of endophytic fungi and a pathogenic strain of S. sclerotiorum were used in the challenge method. With the aid of this method, four endophytes with the best antagonistic activity against S. sclerotiorum were selected. Pathogen growth inhibition zones were considered indicative of antibiosis. The percentages of pathogenic mycelia growth were measured both with and without the antagonist, resulting in growth reductions of 46.7% to 50.0% for S. sclerotiorum. These analyses were performed by evaluating the endophytic/pathogenic mycelia growth in mm/day over an eight-day period of antagonistic tests. PMID:24031320

  18. Newborn First Feed and Prelacteal Feeds in Mansoura, Egypt

    PubMed Central

    Abdel-Hady, Doaa M.

    2014-01-01

    Background. Prelacteal feed (feeding any other substance before first breastfeeding) appears to be common despite its harmful effects. By definition a child provided with prelacteal feed (PLF) is not exclusively breastfed and PLF has many implications for the success and early initiation of breastfeeding. Objectives. To describe the prevalence of, nature of, and reasons for and factors associated with PLF. Methods. 647 mother-infant dyads were studied. Data was collected about the sociodemographic features of the family and baby, maternity care, the type of first feed before suckling, and causes of PLF. Maternal weight and height were measured and body mass index was calculated. Results. About 58% of newborns received prelacteal feeds. The commonest PLF was sugar/glucose water (39.6%). The most frequent reasons for giving PLF are tradition (61.0%) and mother's/mother in law's advice (58.3%). The logistic regression revealed that the independent predictors of PLF are urban residence; maternal education; father's education; low, middle, and high social class; maternal obesity; receiving antenatal care at private clinics and no antenatal care; Caesarean section; female babies; low birth weight; and admission to neonatal intensive care. Conclusion. Indiscriminate use of PLF should be discouraged in medical education and in antenatal maternal health education. PMID:24895560

  19. Feeding programs promoting daily feed intake stability in rabbit males reduce sperm abnormalities and improve fertility.

    PubMed

    Pascual, J J; Marco-Jiménez, F; Martínez-Paredes, E; Ródenas, L; Fabre, C; Juvero, M A; Cano, J L

    2016-08-01

    Feeding programs promoting daily feed intake (DFI) stability in rabbit males could be useful to ensure successful coverage of their nutritional requirements and for continued production of quality semen. To evaluate two feeding systems designed to reduce DFI variability, 115 rabbit males at age 1.2 years were randomly assigned to three different treatments for 294 days: CS, animals fed ad libitum with a control diet (127-g starch and 281-g total soluble fiber [hemicellulose + soluble fiber] kg(-1) dry matter); SF, males fed ad libitum with diet enriched in soluble fiber (86-g starch and 330-g total soluble fiber kg(-1) dry matter); and R, animals fed with CS diet but daily restricted to maintenance requirements. Feed intake, body weight, body condition, and variability of DFI were controlled every 42 days, and individual semen volume and sperm motility, concentration, acrosome status, and abnormalities every 15 days. In six commercial farms, the number of females inseminated, pregnant and kindling, as well as the number of kits born alive, was registered for 15,893 inseminations with pooled semen from each treatment. DFI was significantly lower for R males than for the other treatments (on average, -12 ± 4 g/day; P < 0.001). Daily weight gain of R males was close to zero and significantly lower than in the other groups (-1.42 g/day; P < 0.001). Variability of DFI was significantly (P < 0.01) lower for R males (7%) than for males of dietary treatments CS (13%), with SF males showing intermediate values (11%). Semen from R males presented lower sperm abnormalities (-5.9%; P < 0.05) and higher percentages of normal and motile spermatozoa (-3.4% than SF males; P < 0.05). Dietary treatments formulated to reduce DFI variability (SF and R) led to an improvement of kindling to pregnant and kindling to insemination ratio (+0.039 and + 0.060 ± 0.015, respectively; P < 0.05) compared with CS treatment. In conclusion, a moderate restriction of rabbit

  20. How the pilidium larva feeds

    PubMed Central

    2013-01-01

    Introduction The nemertean pilidium is a long-lived feeding larva unique to the life cycle of a single monophyletic group, the Pilidiophora, which is characterized by this innovation. That the pilidium feeds on small planktonic unicells seems clear; how it does so is unknown and not readily inferred, because it shares little morphological similarity with other planktotrophic larvae. Results Using high-speed video of trapped lab-reared pilidia of Micrura alaskensis, we documented a multi-stage feeding mechanism. First, the external ciliation of the pilidium creates a swimming and feeding current which carries suspended prey past the primary ciliated band spanning the posterior margins of the larval body. Next, the larva detects prey that pass within reach, then conducts rapid and coordinated deformations of the larval body to re-direct passing cells and surrounding water into a vestibular space between the lappets, isolated from external currents but not quite inside the larva. Once a prey cell is thus captured, internal ciliary bands arranged within this vestibule prevent prey escape. Finally, captured cells are transported by currents within a buccal funnel toward the stomach entrance. Remarkably, we observed that the prey of choice – various cultured cryptomonads – attempt to escape their fate. Conclusions The feeding mechanism deployed by the pilidium larva coordinates local control of cilia-driven water transport with sensorimotor behavior, in a manner clearly distinct from any other well-studied larval feeding mechanisms. We hypothesize that the pilidium’s feeding strategy may be adapted to counter escape responses such as those deployed by cryptomonads, and speculate that similar needs may underlie convergences among disparate planktotrophic larval forms. PMID:23927417