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Sample records for ad lib feeding

  1. Recovery from activity-stress ulcer by ad lib feeding in rats.

    PubMed

    Hirao, M; Tanaka, M; Emoto, H; Ishii, H; Yokoo, H; Yoshida, M; Tsuda, A

    1997-12-31

    In order to investigate the recovery from activity-stress ulcers by ad lib-feeding and/or cessation of running, male Wistar rats were exposed to the activity-stress paradigm, and the rats that revealed hypothermia (their rectal temperature fell below 36 degrees C) were sacrificed either immediately or after several 24 h periods of healing. Rats that were sacrificed immediately after the appearance of hypothermia and those that were exposed to restricted feeding plus cessation of running revealed severe activity-stress ulcers, whereas few ulcers were observed in rats given ad lib-feeding and those that were given ad lib-feeding plus cessation of running. Although no significant differences in relative weights of spleen and thymus were obtained among the different recovery conditions, the relative weights of the adrenal glands were highest in the restricted feeding plus cessation of running group, whereas, the other animals exposed to the activity-stress paradigm showed no differences. These results indicate that activity-stress ulcers recover under conditions of ad lib-feeding within 24 h, but they are not influenced by cessation of running. These data also suggest that organ weights are not affected by any manipulations employed in the present study.

  2. Toxicity of ad lib. overfeeding: effects on cardiac tissue.

    PubMed

    Faine, L A; Diniz, Y S; Almeida, J A; Novelli, E L B; Ribas, B O

    2002-05-01

    The aim of the present study was to determine the effects of ad lib. overfeeding and of dietary restriction (DR) on oxidative stress in cardiac tissue. Lipoperoxide concentrations were decreased and antioxidant enzymes were increased in moderate-DR-fed rats. Severe-DR induced increased lipoperoxide concentrations. Overfeeding increased lipoperoxide levels in cardiac tissue. Total superoxide dismutase (SOD) and Cu-Zn superoxide dismutase (Cu-Zn SOD) activities were decreased in cardiac tissue at 35 days of overfeeding. As no changes in glutathione peroxidase (GSH-Px) were observed in overfed rats, while SOD and Cu-Zn SOD activities were decreased in these animals, it is assumed that superoxide anion is an important intermediate in the toxicity of ad lib. overfeeding. Overfeeding induced alterations in markers of oxidative stress in cardiac tissue.

  3. Ad lib caffeine consumption, symptoms of caffeinism, and academic performance.

    PubMed

    Gilliland, K; Andress, D

    1981-04-01

    The authors explored the relationship between ad lib caffeine consumption in college students and the incidence of caffeinism, characterized by heightened anxiety, depression, and various psychophysiological reactions. Students were randomly selected from four groups (abstainers from caffeine and low, moderate, and high consumers). A survey battery assessed the effects of caffeine, incidence of psychophysiological disorders, state-trait anxiety, and depression. The moderate and high consumer groups combined reported significantly higher trait anxiety and depression scores when compared with abstainers. The high consumer group also reported significantly higher levels of symptoms of caffeinism, higher frequency of psychophysiological disorders, and lower academic performance.

  4. Inaccessible food cues affect stress and weight gain in calorically-restricted and ad lib fed rats.

    PubMed

    Coelho, Jennifer S; Polivy, Janet; Fleming, Alison; Hargreaves, Duane; Herman, C Peter; Lao, Grace

    2010-02-01

    Research suggests that caloric restriction (CR) is beneficial; however, the effects of CR in the context of food cues are unclear. A 2 (food cue vs. no cue)x2 (CR vs. ad lib) between-subjects design was employed to test these effects in 40 rats. It was predicted that cue exposure and CR would induce stress, and that these factors might interact synergistically. The results demonstrated that cue-exposed CR rats weighed less than did non-exposed CR rats. A blunted stress response was evident in CR rats relative to ad lib rats. Finally, cue-exposed rats had higher corticosterone levels and body weight during ad lib feeding than did non-cued rats. These results suggest that both CR and chronic food-cue exposure can be stressful, and the implications of this research are discussed in the context of humans' 'obesigenic' environment.

  5. Ego depletion increases ad-lib alcohol consumption: investigating cognitive mediators and moderators.

    PubMed

    Christiansen, Paul; Cole, Jon C; Field, Matt

    2012-04-01

    When self-control resources are depleted ("ego depletion"), alcohol-seeking behavior becomes closely associated with automatic alcohol-related processing biases (e.g., Ostafin, Marlatt, & Greenwald, 2008). The current study aimed to replicate and extend these findings, and also to investigate whether the effects of ego depletion on drinking behavior would be mediated by temporary impairments in executive function or increases in impulsivity. Eighty heavy social drinkers (46 female) initially completed measures of automatic approach tendencies (stimulus response compatibility [SRC] task) and attentional bias (visual probe task) elicited by alcohol-related cues. Participants were then exposed to either an ego depletion manipulation or a control manipulation, before completing a bogus taste test in order to assess ad-lib alcohol consumption. In a subsequent testing session, we examined effects of the ego depletion manipulation (vs. control manipulation) on 3 aspects of executive function (inhibitory control, phonemic fluency, and delay discounting). Results indicated that the ego depletion manipulation increased ad-lib drinking, relative to the control manipulation. Automatic approach tendencies, but not attentional bias, predicted ad-lib drinking, although this effect was not moderated by ego depletion. Ego depletion had inconsistent effects on measures of executive function and impulsivity, and none of these measures mediated the effect of ego depletion on ad-lib drinking. However, the effect of ego depletion on ad-lib drinking was mediated by self-reported effort in suppressing emotion and thoughts during the manipulation. Implications for the effects of self-control strength on drinking behavior, and cognitive mediators of these effects, are discussed.

  6. Meal patterns and meal-induced metabolic changes in calves fed milk ad lib.

    PubMed

    Senn, M; Gross-Lüem, S; Leuenberger, H; Langhans, W

    The feeding behavior of 11 calves fed milk ad lib was characterized and analyzed at the age of 5 weeks, and the short-term changes in the plasma concentrations of various metabolites (glucose, lactate, free fatty acids, triglycerides, beta-hydroxybutyrate) and insulin in relation to a representative spontaneous milk meal were measured during the following week. In a 6-day period, the calves consumed 287 (=86%) of a total of 335 milk meals during the light phase from 0500-2200 [on average, 4.4 +/- 0.5 (mean +/- SEM) meals]. The meal size and duration during light were 2.0 +/- 0.3 kg and 5.3 +/- 0.3 min, respectively. However, only 0.7 +/- 0.1 milk meals of similar size and duration were consumed during the dark phase. The plasma concentrations of insulin and glucose increased in response to the spontaneous milk meal and remained elevated for at least 2 h after meal end. The plasma concentrations of triglycerides, free fatty acids, and beta-hydroxybutyrate also increased after meal termination, and remained elevated until 40 min (triglycerides, free fatty acids) and 60 min (beta-hydroxybutyrate) after meal end, respectively. The observed spontaneous milk intake patterns were similar to the natural suckling behavior described for calves, suggesting that the conditions of the present experiment did not disrupt the animals' natural feeding behavior. Some of the profound metabolic changes in relation to a spontaneous milk meal might contribute to the control of milk intake in calves, but further experiments are necessary to test this idea.

  7. P300 during response inhibition is associated with ad-lib alcohol consumption in social drinkers.

    PubMed

    Jones, Andrew; Field, Matt; Christiansen, Paul; Stancak, Andrej

    2013-06-01

    Reduced amplitude of the cortical P300 event-related potential (ERP) component during response inhibition is associated with vulnerability to alcohol use disorders. In the current study, we investigated the effect of an experimental manipulation of response conflict on the amplitude of the P300 component during response inhibition, and examined whether individual differences in the amplitude of this P300 component would predict voluntary ad-lib alcohol consumption, in social drinkers. Using a repeated measures design, 16 participants performed a stop-signal task after receiving instructions that either emphasised or de-emphasised response conflict while their electroencephalogram (EEG) was concurrently recorded, before their ad-lib drinking was assessed. Results revealed that task instructions had the predicted effects on behavioural indices of response inhibition and the associated P300 components. Most importantly, individual differences in the amplitude of P300 subcomponents during response inhibition were negatively correlated with ad-lib alcohol consumption. Results provide the first experimental support for theoretical models that posit that reduced amplitude of the P300 during response inhibition is associated with alcohol-seeking behaviour in humans.

  8. Acute effects of nicotine and mecamylamine on tobacco withdrawal symptoms, cigarette reward and ad lib smoking.

    PubMed

    Rose, J E; Behm, F M; Westman, E C

    2001-02-01

    Separate and combined effects of nicotine and the nicotinic antagonist mecamylamine were studied in 32 healthy volunteer smokers after overnight abstinence from smoking. Subjects participated in three sessions (3 h each), during which they wore skin patches delivering either 0 mg/24 h, 21 mg/24 h or 42 mg/24 h nicotine. Thirty-two subjects were randomly assigned to two groups receiving oral mecamylamine hydrochloride (10 mg) vs. placebo capsules. Two and one-half hours after drug administration, subjects were allowed to smoke ad lib, rating the cigarettes for rewarding and aversive effects. Transdermal nicotine produced a dose-related reduction in the subjective rewarding qualities of smoking. Nicotine also reduced craving for cigarettes and this effect was attenuated, but not eliminated, by mecamylamine. Mecamylamine blocked the discriminability of high vs. low nicotine puffs of smoke, and increased nicotine intake substantially during the ad lib smoking period. Some of the psychophysiological effects of each drug (elevation in blood pressure from nicotine, sedation and decreased blood pressure from mecamylamine) were offset by the other drug. The results supported the hypothesis that nicotine replacement can alleviate tobacco withdrawal symptoms even in the presence of an antagonist such as mecamylamine. Mecamylamine did not precipitate withdrawal beyond the level associated with overnight cigarette deprivation, suggesting its effects were primarily due to offsetting the action of concurrently administered nicotine as opposed to blocking endogenous cholinergic transmission.

  9. Ad lib smoking in post-traumatic stress disorder: an electronic diary study.

    PubMed

    Beckham, Jean C; Wiley, Matthew T; Miller, Susannah C; Dennis, Michelle F; Wilson, Sarah M; McClernon, F Joseph; Calhoun, Patrick S

    2008-07-01

    Using ambulatory methods for 1 week of monitoring, this study investigated the association between smoking and situational cues in 22 smokers with post-traumatic stress disorder (PTSD) and 23 smokers without PTSD. Generalized estimating equations contrasted 1,759 smoking and 1,088 nonsmoking situations by group status controlling for multiple covariates. PTSD smokers reported higher stress and PTSD symptoms across daily activities. For all smokers, higher nicotine dependence, craving, food and caffeine consumption, and being outside were related to smoking. PTSD smokers were more likely to smoke when experiencing PTSD symptoms, anxiety, and stress. Following smoking, smokers with PTSD reported a significant reduction in negative affect. These results are consistent with previous ambulatory findings regarding mood in smokers, and underscore that in smokers with PTSD, PTSD symptom variables as well as stress and anxiety are significantly associated with ad lib smoking.

  10. 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

  11. Individual Differences in Approach and Avoidance Inclinations Moderate the Effect of Self-Control Depletion on Ad-Lib Drinking

    PubMed Central

    Schlauch, Robert C.; Christensen, Rita L.; Derrick, Jaye L.; Crane, Cory A.; Collins, R. Lorraine

    2015-01-01

    Background The current study sought to examine how exerting self-control to inhibit stereotype use affects alcohol consumption. In addition, we sought to expand previous findings via examination of how individual differences in motivations to approach or avoid alcohol consumption interact with self-control depletion to determine the regulation of ad-lib drinking behavior. Methods Sixty-one social drinkers (31 female) were recruited to participate in a socially relevant self-control depletion task in which they were randomly assigned to one of two creative writing conditions: 1) the self-control depletion condition with explicit instructions to refrain from using stereotypes, or 2) the non-depletion condition in which no instructions were given regarding the use of stereotypes. Participants then completed an ad-lib drinking task and self-report questionnaires pertaining to their motivation to consume alcohol. Results As predicted, results indicated a significant three-way interaction between depletion condition, approach inclinations, and avoidance inclinations. Specifically, self-control depletion predicted greater drinking disinhibition (i.e., mean sip size, total alcohol consumption) only among participants high in both approach and avoidance. Conclusions Taken together, results from the current study highlight the importance of both approach and avoidance inclinations in the failure to regulate alcohol consumption following a routine, socially relevant form of self-control depletion. Our results also suggest that the high approach / high avoidance motivational profile may predict the greatest risk among those actively trying to regulate their drinking. PMID:26756800

  12. Gender differences in immediate antecedents of ad lib cigarette smoking in smokers with and without posttraumatic stress disorder: a preliminary report.

    PubMed

    Dennis, Michelle F; Clancy, Carolina P; Beckham, Jean C

    2007-12-01

    Using ambulatory methods for monitoring, this study investigated gender differences regarding the association between smoking and situational cues in 63 smokers with posttraumatic stress disorder (PTSD) and 32 smokers without PTSD. Smokers were instructed to complete a diary entry each time an ambulatory blood pressure monitor took a reading and each time they prepared to smoke. Generalized estimating equations contrasted 682 smoking and 444 nonsmoking situations by group status. For all smokers, ad lib smoking was strongly related to craving. For women with PTSD, ad lib smoking was strongly related to total PTSD symptoms, PTSD reexperiencing symptoms, and PTSD hyperarousal symptoms. For men with PTSD, ad lib smoking was significantly related to negative affect, PTSD reexperiencing symptoms, restlessness, and worry. No other mood antecedents were significant for women or men smokers without PTSD. These results are consistent with previous studies documenting gender differences in smoking behavior, and underscore the importance of examining gender differences in psychiatric samples.

  13. A comparison of the anticipated and pharmacological effects of alcohol on cognitive bias, executive function, craving and ad-lib drinking.

    PubMed

    Christiansen, Paul; Rose, Abigail K; Cole, Jon C; Field, Matt

    2013-01-01

    Acute alcohol administration alters automatic processing of alcohol-related cues, impairs executive functions and increases alcohol seeking. Few studies have investigated the effects of expecting to receive alcohol on these measures. Thirty-one social drinkers completed three experimental sessions receiving either 0.65 g/kg alcohol, a placebo and a control beverage (which they knew was not alcoholic) before reporting craving and completing a test battery including a measure of automatic alcohol-approach tendencies (stimulus response compatibility task), a measure of executive function (Controlled Oral Word Association Task (COWAT)) and a taste test assessing ad-lib drinking. Results indicated that alcohol administration impaired performance on the COWAT and increased ad-lib drinking; however, there were no significant differences on these measures after administration of placebo versus control beverages. Craving was increased after alcohol and (to a lesser extent) after placebo. Automatic alcohol-approach tendencies were pronounced after both alcohol and placebo compared to the control beverage, with no difference between alcohol and placebo. Results suggest craving is sensitive to the anticipated and pharmacological effects of alcohol, alcohol-approach tendencies are particularly sensitive to the anticipated effects of alcohol, and measures of executive function and ad-lib drinking are affected by the pharmacological, but not the anticipated, effects of alcohol.

  14. Adding Bite to the Bark: Using LibGuides2 Migration as Impetus to Introduce Strong Content Standards

    ERIC Educational Resources Information Center

    Fritch, Melia; Pitts, Joelle E.

    2016-01-01

    The authors discuss the long-term accumulation of unstandardized and inaccessible content within the Libguides system and the decision-making process to create and implement a set of standards using the migration to the LibGuides2 platform as a vehicle for change. Included in the discussion are strategies for the creation of standards and…

  15. 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

  16. Effects of the nicotinic receptor antagonist mecamylamine on ad-lib smoking behavior, topography, and nicotine levels in smokers with and without schizophrenia: a preliminary study.

    PubMed

    McKee, Sherry A; Weinberger, Andrea H; Harrison, Emily L R; Coppola, Sabrina; George, Tony P

    2009-12-01

    Individuals with schizophrenia have higher plasma nicotine levels in comparison to non-psychiatric smokers, even when differences in smoking are equated. This difference may be related to how intensely cigarettes are smoked but this has not been well studied. Mecamylamine (MEC), a non-competitive nicotinic acetylcholine receptor (nAChR) antagonist, which has been shown to increase ad-lib smoking and to affect smoking topography, was used in the current study as a pharmacological probe to increase our understanding of smoking behavior, smoking topography, and resulting nicotine levels in smokers with schizophrenia. This preliminary study used a within-subject, placebo-controlled design in smokers with schizophrenia (n=6) and healthy control smokers (n=8) to examine the effects of MEC (10mg/day) on ad-lib smoking behavior, topography, nicotine levels, and tobacco craving across two smoking deprivation conditions (no deprivation and 12-h deprivation). MEC, compared to placebo, increased the number of cigarettes smoked and plasma nicotine levels. MEC increased smoking intensity and resulted in greater plasma nicotine levels in smokers with schizophrenia compared to controls, although these results were not consistent across deprivation conditions. MEC also increased tobacco craving in smokers with schizophrenia but not in control smokers. Our results suggest that antagonism of high-affinity nAChRs in smokers with schizophrenia may prompt compensatory smoking, increasing the intensity of smoking and nicotine exposure without alleviating craving. Further work is needed to assess whether nicotine levels are directly mediated by how intensely the cigarettes are smoked, and to confirm whether this effect is more pronounced in smokers with schizophrenia.

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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.

  3. Region-specific down-regulation of Crhr1 gene expression in alcohol-preferring msP rats following ad lib access to alcohol.

    PubMed

    Hansson, Anita C; Cippitelli, Andrea; Sommer, Wolfgang H; Ciccocioppo, Roberto; Heilig, Markus

    2007-03-01

    Corticotropin-releasing hormone 1 receptors (CRH-R1) mediate increased behavioral sensitivity to stress and excessive alcohol self-administration following a history of dependence. It was recently demonstrated that the genetically selected alcohol-preferring msP rat line replicates many characteristics of the post-dependent state, due to an innate up-regulation of the Crhr1 transcript in several limbic areas related to alcohol drinking motivation. Here, we examined whether voluntary alcohol consumption might be able to down-regulate Crhr1 transcript levels in msP rats in brain areas where elevated expression previously has been shown. Within central and medial amygdala (CeA, MeA), as well as the Nc. Accumbens, 2 weeks'ad lib access to alcohol led to a highly significant down-regulation of the Crhr1 transcript. Alcohol-induced Crhr1 down-regulation was not seen in cingulate cortex. These data support that recruitment of CRH-R1 signaling within components of the extended amygdala drives excessive alcohol intake, and that alcohol is voluntarily consumed in part for its ability to reduce CRH-R1 activity in this region.

  4. LibVMI

    SciTech Connect

    Payne, Bryan D.

    2011-09-28

    LibVMI is an introspection library focused on reading and writing memory from virtual machines (VMs). For convenience, LibVMI also provides functions for accessing CPU registers, pausing and unpausing a VM, printing binary data, and more. LibVMI is designed to work across multiple virtualization platforms. LibVMI currently supports VMs running in either Xen or KVM. LibVMI also supports reading physical memory snapshots when saved as a file.

  5. Feed intake and competition in ewes on ad libitum or semi-restricted feeding of grass silage and hay.

    PubMed

    Bøe, K E; Ottosen, A M; Andersen, I L

    2012-11-01

    The aim of the present experiment was to investigate the effect of feeding level and type of roughage on feed intake, feeding behavior and competition of ewes. A 2 × 2 factorial experiment was conducted with amount of roughage available (ad libitum or semi restricted) and type of roughage (grass silage or hay) as main factors. Forty-eight ewes were randomly assigned to 8 groups of 6 ewes. All groups were subjected to all 4 treatments, each treatment period lasted 7 d, and the order of treatments was rotated systematically. The ewes were video recorded for the 2 last days of each treatment period and feeding and general activity were scored every 10 min. All aggressive interactions and displacement at the feed barrier were scored continuously the first 3 h after feeding. Daily feed intake (P < 0.0001) and DMI (P < 0.0001) were both greater in the silage than in the hay treatment. Ewes in the semi-restricted treatment spent less time feeding (P < 0.0001), had a greater individual variation in feeding time (P < 0.05) and spent more time queuing for feed (standing maximum 1.5 m from the feeding barrier with the head towards the feed; P < 0.0001). Individual data showed that 5 ewes fed hay and 3 ewes fed silage reduced their time spent feeding more than 50% when the feeding level was reduced. When fed hay, the level of feeding did not affect number of aggressive interactions or displacements, but when fed silage the number of aggressive interactions (P < 0.01) and the number of displacements (P < 0.05) were much greater in the semi-restricted than in the ad libitum treatment. We conclude that even a minor restriction in the level of feeding will decrease time spent feeding and increase queuing and number of aggressive interactions when feeding space is also restricted, and that the increase in aggressive interactions is mainly for ewes fed grass silage.

  6. Influence of ad Libitum Feeding of Piglets With Bacillus Subtilis Fermented Liquid Feed on Gut Flora, Luminal Contents and Health

    PubMed Central

    He, Yuyong; Mao, Chunxia; Wen, Hong; Chen, Zhiyu; Lai, Tao; Li, Lingyu; Lu, Wei; Wu, Huadong

    2017-01-01

    Some scholars caution that long-term ad libitum feeding with probiotic fermented food poses potential health risks to baby animals. We conducted a feeding experiment to investigate the influence of ad libitum feeding of pre-and post-weaned piglets with a Bacillus subtilis fermented diet on the gut microbiome, gut metabolomic profiles, bile acid metabolism, proinflammatory cytokines and faecal consistency. Compared with piglets fed a Bacillus subtilis-supplemented pellet diet, piglets fed the Bacillus subtilis fermented liquid diet had lower intestinal bacterial diversity (P > 0.05), higher intestinal fungal diversity (P > 0.05), more Firmicutes (P > 0.05), fewer Bacteroidetes, Actinobacteria and Proteobacteria (P > 0.05), higher concentrations of 3-hydroxypropionic acid (P < 0.05), orotic acid (P < 0.05), interleukin-6 (P < 0.01), lactic acid (P < 0.01), deoxycholic acid (P > 0.05) and lithocholic acid (P < 0.01) and a higher incidence of diarrhoea (P > 0.05). The data show that ad libitum feeding of piglets with a Bacillus subtilis fermented liquid diet during the suckling and early post-weaning periods promotes the growth of lactic acid bacteria, bile salt hydrolase-active bacteria and 7a-dehydroxylase-active bacteria in the intestinal lumen; disturbs the normal production of lactic acid, orotic acid and unconjugated bile acids; and increases circulating interleukin-6 levels and diarrhoea incidence. PMID:28291252

  7. Influence of ad Libitum Feeding of Piglets With Bacillus Subtilis Fermented Liquid Feed on Gut Flora, Luminal Contents and Health.

    PubMed

    He, Yuyong; Mao, Chunxia; Wen, Hong; Chen, Zhiyu; Lai, Tao; Li, Lingyu; Lu, Wei; Wu, Huadong

    2017-03-14

    Some scholars caution that long-term ad libitum feeding with probiotic fermented food poses potential health risks to baby animals. We conducted a feeding experiment to investigate the influence of ad libitum feeding of pre-and post-weaned piglets with a Bacillus subtilis fermented diet on the gut microbiome, gut metabolomic profiles, bile acid metabolism, proinflammatory cytokines and faecal consistency. Compared with piglets fed a Bacillus subtilis-supplemented pellet diet, piglets fed the Bacillus subtilis fermented liquid diet had lower intestinal bacterial diversity (P > 0.05), higher intestinal fungal diversity (P > 0.05), more Firmicutes (P > 0.05), fewer Bacteroidetes, Actinobacteria and Proteobacteria (P > 0.05), higher concentrations of 3-hydroxypropionic acid (P < 0.05), orotic acid (P < 0.05), interleukin-6 (P < 0.01), lactic acid (P < 0.01), deoxycholic acid (P > 0.05) and lithocholic acid (P < 0.01) and a higher incidence of diarrhoea (P > 0.05). The data show that ad libitum feeding of piglets with a Bacillus subtilis fermented liquid diet during the suckling and early post-weaning periods promotes the growth of lactic acid bacteria, bile salt hydrolase-active bacteria and 7a-dehydroxylase-active bacteria in the intestinal lumen; disturbs the normal production of lactic acid, orotic acid and unconjugated bile acids; and increases circulating interleukin-6 levels and diarrhoea incidence.

  8. ParaDIS_lib

    SciTech Connect

    Cook, Richard D.

    2016-05-25

    The ParaDIS_lib software is a project that is funded by the DOE ASC Program. Its purpose is to provide visualization and analysis capabilities for the existing ParaDIS parallel dislocation dynamics simulation code.

  9. LibIsopach

    SciTech Connect

    Brunhart-Lupo, Nicholas

    2016-12-06

    LibIsopach is a toolkit for high performance distributed immersive visualization, leveraging modern OpenGL. It features a multi-process scenegraph, explicit instance rendering, mesh generation, and three-dimensional user interaction event processing.

  10. Different milk feeding intensities during the first 4 weeks of rearing in dairy calves: Part 1: Effects on performance and production from birth over the first lactation.

    PubMed

    Korst, M; Koch, C; Kesser, J; Müller, U; Romberg, F-J; Rehage, J; Eder, K; Sauerwein, H

    2017-04-01

    We aimed to test the effects of ad libitum feeding of whole milk (WM) or milk replacer (MR) versus restrictive feeding of MR during the first 4 wk of life on growth performance and on milk yield in the first lactation. We studied 57 German Holstein calves (29 females, 28 males) from birth until d 110 of life (trial 1). The 28 females from trial 1 were further studied during their first lactation (trial 2). In trial 1, all calves were randomly allocated at birth to 1 of 3 groups: MR-res [n = 20, 6.78 kg MR (11.5% solids)/calf per day], MR-ad lib (n = 17, 13.8% solids) or WM-ad lib (n = 20). All calves received colostrum ad libitum from their dam until d 3 of age. From d 4 to 27, calves were fed according to their group regimen. From d 28 to 55, all calves received MR-res feeding and were then gradually weaned until d 69. We recorded body weight (until d 110) and feed intake (amount, metabolizable energy, and frequency of liquid feed intake until weaning). We estimated the profitability of the different feeding regimens, taking into account income from milk yield (trial 2) and feed costs during rearing. In trial 1, the calves from WM-ad lib and MR-ad lib had total metabolizable energy intakes 2.02- and 1.65-fold greater than the MR-res group during the first 4 wk of life. During this period, concentrate intake did not differ among groups, but tended to be greater in WM-ad lib than in MR-ad lib calves from d 28 to 69. The MR-res calves visited the automatic feeders more often than the ad libitum-fed groups during differential feeding, but 70% of the visits were unrewarded (<10% in the ad libitum-fed calves). When all calves were fed at the MR-res level, the average proportion of unrewarded visits was 65% in all groups. Average daily gain and body weight were greater among MR-ad lib and WM-ad lib calves than among MR-res animals during the first 4 wk of life, but not from d 1 to 110. In trial 2, age at first calving, dry matter intake, and body weight over the first 10

  11. LIBS for Martian Moons eXploration (MMX)

    NASA Astrophysics Data System (ADS)

    Kameda, S.; Horiuchi, M.; Cho, Y.; Ishibashi, K.; Wada, K.; Mikouchi, T.; Nakamura, T.; Sugita, S.

    2016-10-01

    JAXA's Martian Moons Exploration (MMX) is planned to be a sample return mission from Phobos, one of the satellites of Mars. We propose adding a laser-induced breakdown spectrometer (LIBS), which enables to determine the origin of the moons.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. Lib, transcriptionally induced in senile plaque-associated astrocytes, promotes glial migration through extracellular matrix.

    PubMed

    Satoh, Kazuki; Hata, Mitsumi; Shimizu, Tomoko; Yokota, Hiroshi; Akatsu, Hiroyasu; Yamamoto, Takayuki; Kosaka, Kenji; Yamada, Tatsuo

    2005-09-23

    In an effort to identify astrocyte-derived molecules that may be intimately associated with progression of Alzheimer's disease (AD), Lib, a type I transmembrane protein belonging to leucine-rich repeat superfamily, has been identified as a distinctly inducible gene, responsive to beta-amyloid as well as pro-inflammatory cytokines in astrocytes. To evaluate the roles of Lib in AD, we investigated Lib expression in AD brain. In non-AD brain, Lib mRNA has been detected in neurons but not in quiescent astrocytes. On the contrary, in AD brain, Lib mRNA is expressed in activated astrocytes associated with senile plaques, but not expressed in neurons around lesions. Lib-expressing glioma cells displayed promotion of migration ability through reconstituted extracellular matrix and recombinant Lib protein bound to constituents of extracellular matrix. These observations suggest that Lib may contribute to regulation of cell-matrix adhesion interactions with respect to astrocyte recruitment around senile plaques in AD brain.

  18. 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

  19. 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.

  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. Oregano Extract Added into the Diet of Dairy Heifers Changes Feeding Behavior and Concentrate Intake

    PubMed Central

    Kolling, Giovani Jacob; Stumpf, Marcelo Tempel; da Cruz, Eduardo Augusto

    2016-01-01

    This experiment aimed to describe the effects of Oregano extract (OE) inclusion into the concentrate fed to dairy heifers on physiological parameters, feeding behavior, intake, and performance. Thirty-two Holstein heifers were randomly distributed into four treatments: C = control, without addition of OE; OE2.5 = 2.5 g; OE5.0 = 5.0 g and OE7.5 = 7.5 g of Oregano extract per heifer/day. Feeding behavior and concentrate intake were assessed individually every day and total dry matter intake (DMI) was determined on the last week of the trial. Compared to control group, OE7.5 reduced by 32% the latency time to approach the feed bunk but increased by 6% the time spent eating the concentrate. Each inclusion of 2.5 grams of OE into the concentrate increased the occurrence of postingestive licking the feed bunk with abundant saliva production 1.2 times (P < 0.01) and tended to increase the occurrence of sneeze events 1.2 times (P < 0.10). No statistical difference was detected between treatments for total DMI, but concentrate DMI was 9% lower for OE7.5 when compared to control and OE2.5. The inclusion of 7.5 grams/day of OE causes small but negative effects in feeding behavior and concentrate intake, without change on total dry matter intake. PMID:28116344

  2. 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

  3. 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…

  4. Lessons Learned from LIBS Calibration Development

    NASA Astrophysics Data System (ADS)

    Dyar, M. D.; Breves, E. A.; Lepore, K. H.; Boucher, T. F.; Giguere, S.

    2016-10-01

    More than two decades of work have been dedicated to development of robust standards, data processing, and calibration tools for LIBS. Here we summarize major considerations for improving accuracy of LIBS chemical analyses.

  5. 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.

  6. 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.

  7. Reduced particle size wheat bran is butyrogenic and lowers Salmonella colonization, when added to poultry feed.

    PubMed

    Vermeulen, K; Verspreet, J; Courtin, C M; Haesebrouck, F; Ducatelle, R; Van Immerseel, F

    2017-01-01

    Feed additives, including prebiotics, are commonly used alternatives to antimicrobial growth promoters to improve gut health and performance in broilers. Wheat bran is a highly concentrated source of (in)soluble fiber which is partly degraded by the gut microbiota. The aim of the present study was to investigate the potential of wheat bran as such to reduce colonization of the cecum and shedding of Salmonella bacteria in vivo. Also, the effect of particle size was evaluated. Bran with an average reduced particle size of 280μm decreased levels of cecal Salmonella colonization and shedding shortly after infection when compared to control groups and groups receiving bran with larger particle sizes. In vitro fermentation experiments revealed that bran with smaller particle size was fermented more efficiently, with a significantly higher production of butyric and propionic acid, compared to the control fermentation and fermentation of a larger fraction. Fermentation products derived from bran with an average particle size of 280μm downregulated the expression of hilA, an important invasion-related gene of Salmonella. This downregulation was reflected in an actual lowered invasive potential when Salmonella bacteria were pretreated with the fermentation products derived from the smaller bran fraction. These data suggest that wheat bran with reduced particle size can be a suitable feed additive to help control Salmonella infections in broilers. The mechanism of action most probably relies on a more efficient fermentation of this bran fraction and the consequent increased production of short chain fatty acids (SCFA). Among these SCFA, butyric and propionic acid are known to reduce the invasion potential of Salmonella bacteria.

  8. 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

  9. Influence of a pig respiratory disease on the pharmacokinetic behaviour of amoxicillin after oral ad libitum administration in medicated feed.

    PubMed

    Godoy, C; Castells, G; Martí, G; Capece, B P S; Pérez, F; Colom, H; Cristòfol, C

    2011-06-01

    The pharmacokinetic properties of amoxicillin in healthy and respiratory-diseased pigs were studied, after ad libitum administration of medicated feed. In addition, amoxicillin dose linearity and drug penetration into respiratory tract tissues were evaluated in diseased animals. The respiratory disease involves porcine reproductive and respiratory syndrome virus and bacterial agents such as Pasteurella multocida, Bordetella bronchiseptica and Streptococcus suis. Typical clinical signs and gross lesions of respiratory disease were observed. The plasma pharmacokinetic analysis was performed by means of a noncompartmental approach. After single intravenous bolus administration of amoxicillin to healthy pigs, the steady-state volume of distribution was 0.61 L/kg, the total plasma clearance was 0.83 L/h/kg and the mean residence time was 0.81 h. After oral bolus administration, the mean absorption time was 1.6 h and the peak plasma concentration (3.09 μg/mL) reached at 1.1 h postadministration. The oral bioavailability was 34%. For oral ad libitum administration, plasma concentration-time profiles were related to the feeding behaviour. Plasma concentrations at steady-state were established between 12 and 120 h. The pharmacokinetic parameters calculated (C(maxss) , C(minss) , C(avss) and AUC(24ss) ) showed significantly lower values in healthy pigs compared to diseased animals. This was in accordance with the significantly higher amoxicillin bioavailability (44.7% vs. 14.1%) and longer absorption period observed in diseased pigs. Amoxicillin dose linearity in diseased animals was established in a dose range of 4-18 mg/kg. On the other hand, tissue distribution ratio in diseased animals was 0.65 for bronchial mucosa, 0.48 for lung tissue and 0.38 for lymph nodes. Our results suggest that the pharmacokinetic properties and disposition of amoxicillin can be influenced by the disease state or by related factors such as changes in the gastrointestinal transit.

  10. 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

  11. 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

  12. Effects of feed consumption rate of beef cattle offered a diet supplemented with nitrate ad libitum or restrictively on potential toxicity of nitrate.

    PubMed

    Lee, C; Araujo, R C; Koenig, K M; Beauchemin, K A

    2015-10-01

    The objective of the study was to investigate the effects of feed consumption rate on potential toxicity, rumen fermentation, and eating behavior when beef heifers were fed a diet supplemented with nitrate (NI). Twelve ruminally cannulated heifers (827 ± 65.5 kg BW) were used in a randomized complete block design. The experiment consisted of 10-d adaptation, 8-d urea-feeding, and 3-d nitrate-feeding periods. All heifers were fed a diet supplemented with urea (UR) during the adaptation and urea-feeding periods, whereas the NI diet (1.09% NO in dietary DM) was fed during the nitrate-feeding period. After adaptation, heifers were randomly assigned to ad libitum or restrictive feeding (about 80% of ad libitum intake) for the urea- and nitrate-feeding periods. Ad libitum DMI decreased (14.1 vs. 15.1 kg/d; < 0.01) when heifers were fed the NI diet compared with the UR diet. The amount of feed consumed increased ( < 0.01) at 0 to 3 h and decreased ( ≤ 0.03) at 3 to 24 h for restrictive vs. ad libitum feeding of both the UR and NI diets. Compared to the UR diet, the NI diet decreased ( < 0.01) feed consumption at 0 to 3 h and increased ( < 0.02) feed consumption at 3 to 24 h (except feed consumption at 9 to 12 h; = 0.90), indicating nitrate feeding changed the consumption pattern (a more even distribution of feed intake over the day). The increased feed consumption from 0 to 3 h after feeding the NI diet restrictively vs. ad libitum numerically decreased ( = 0.11) rumen pH and numerically or significantly increased ( = 0.01 to 0.28) rumen ammonia, NO, and NO; blood methemoglobin; and plasma NO and NO at 3 h. Regression analysis indicated that increased feed consumption (0 to 3 h) exponentially elevated ( < 0.01; = 0.75) blood methemoglobin, and plasma NO + NO among other rumen and blood variables had the greatest correlation (sigmoid response; < 0.01, = 0.47) with feed consumption (0 to 3 h). Particle size distribution of orts was partially altered ( = 0.02 to 0

  13. 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.

  14. 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

  15. Progress in LIBS for Land Mine Detection

    DTIC Science & Technology

    2010-04-01

    material yields a unique LIBS spectrum. This being the case, a LIBS spectrum should provide a “ fingerprint ” of the material analyzed, and LIBS...the predictor variables (called “ latent variables” [LVs]) are generated while simultaneously considering both intraclass and interclass variance. This...mine simulants. Twenty latent variables were chosen to describe the model spectra based on cross-validation (contiguous block method). Because the

  16. The influence of food restriction versus ad libitum feeding of chow and purified diets on variation in body weight, growth and physiology of female Wistar rats.

    PubMed

    Moraal, M; Leenaars, P P A M; Arnts, H; Smeets, K; Savenije, B S; Curfs, J H A J; Ritskes-Hoitinga, M

    2012-04-01

    Ad libitum (AL) supply of standard chow is the feeding method most often used for rodents in animal experiments. However, AL feeding is known to result in a shorter lifespan and decreased health as compared with restricted feeding. Restricted feeding and thus limiting calorie intake prevents many health problems, increases lifespan and can also increase group uniformity. All this leads to a reduced number of animals needed. So-called standard chows are known to be prone to variation in composition. Synthetic foods have a more standard composition, contributing to group uniformity which, like diet reduction, may decrease the number of animals necessary to obtain statistical significance. In this study, we compared the effects of AL versus restricted feeding (25% reduction in food intake) on standard chow versus synthetic food of three different suppliers on body weight (BW), growth, several blood parameters and organ weights in growing female Wistar rats over a period of 61 days. Diet restriction led to a decreased growth and significantly reduced variation in BW and growth as compared with AL feeding. AL feeding on synthetic diets caused a significantly higher BW gain than on chow diets. Due to experimental design, this same effect occurred on food restriction. Blood parameters and organ weights were affected neither by diet type nor by amount. Incidentally, variations were significantly reduced on food restriction versus AL, and on synthetic diets versus chow diets. This study demonstrates that food restriction versus AL feeding leads to a significantly reduced variation in BW and growth, thereby indicating the potential for reduction when applying this feeding schedule.

  17. 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.

  18. Femtosecond LIBS studies of nitropyrazoles

    NASA Astrophysics Data System (ADS)

    Nageswara Rao, E.; Sunku, Sreedhar; Tewari, Surya P.; Manoj Kumar, G.; Venugopal Rao, S.

    2013-05-01

    We present our initial experimental results from the LIBS studies of pyrazole, 1-nitropyrazole, 3-nitropyrazole, 3,4- dinitropyrazole and 1-methyl- 3,4,5 trinitro pyrazole recorded with femtosecond pulses and performed in argon atmosphere. CN molecular bands in three different spectral regions of 357 nm-360 nm, 384 nm-389 nm and 414 nm -423 nm, C2 swan bands near 460 nm-475 nm, 510 nm- 520 nm and 550 nm-565 nm were observed. The C peak at 247.82 nm, H peak at 656.2 nm have also been observed along with several peaks of O and N. CN/C2, CN/C, C2/C and C2/N ratios were measured from the average of 25 spectra obtained in argon. The effect of number of nitro groups on the atomic and molecular emission has been evaluated. A gate delay of 100 ns and a gate width of 800 ns were used for collecting the spectra.

  19. 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.

  20. 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] =…

  1. 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

  2. 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.

  3. Time-restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high-fat diet.

    PubMed

    Hatori, Megumi; Vollmers, Christopher; Zarrinpar, Amir; DiTacchio, Luciano; Bushong, Eric A; Gill, Shubhroz; Leblanc, Mathias; Chaix, Amandine; Joens, Matthew; Fitzpatrick, James A J; Ellisman, Mark H; Panda, Satchidananda

    2012-06-06

    While diet-induced obesity has been exclusively attributed to increased caloric intake from fat, animals fed a high-fat diet (HFD) ad libitum (ad lib) eat frequently throughout day and night, disrupting the normal feeding cycle. To test whether obesity and metabolic diseases result from HFD or disruption of metabolic cycles, we subjected mice to either ad lib or time-restricted feeding (tRF) of a HFD for 8 hr per day. Mice under tRF consume equivalent calories from HFD as those with ad lib access yet are protected against obesity, hyperinsulinemia, hepatic steatosis, and inflammation and have improved motor coordination. The tRF regimen improved CREB, mTOR, and AMPK pathway function and oscillations of the circadian clock and their target genes' expression. These changes in catabolic and anabolic pathways altered liver metabolome and improved nutrient utilization and energy expenditure. We demonstrate in mice that tRF regimen is a nonpharmacological strategy against obesity and associated diseases.

  4. 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.

  5. 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

  6. Effects of concurrent drug therapy and of feeding on plasma chloramphenicol levels after oral administration of chloramphenicol in dogs.

    PubMed

    Watson, A D

    1977-01-01

    On separate occasions, five fasted adult greyhounds were dosed orally with 50 mg chloramphenicol/kg, both alone and in conjunction with other drugs. The same five dogs were later given 50 mg chloramphenicol/kg when fed ad lib. Chloramphenicol levels in plasma were determined at intervals after dosing. The intial plasma chloramphenicol levels were higher when the drug was administered concurrently with calcium lactate tablets (50 mg/kg) or a proprietary enteric mixture containing kaolin, pectin, aluminium hydroxide and belladonna extract. Lower plasma levels resulted when the antibiotic was given with dry extract of belladonna (20 mg/dog) or intravenous chlorpromazine (2 mg/kg). There was no significant effect with coated ferrous gluconate tablets (30 mg/kg). Feeding ad lib increased the initial chloramphenicol levels, but produced lower levels subsequently.

  7. 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.

  8. 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.

  9. Qualitative evaluation of maternal milk and commercial infant formulas via LIBS.

    PubMed

    Abdel-Salam, Z; Al Sharnoubi, J; Harith, M A

    2013-10-15

    This study focuses on the use of laser-induced breakdown spectroscopy (LIBS) for the evaluation of the nutrients in maternal milk and some commercially available infant formulas. The results of such evaluation are vital for adequate and healthy feeding for babies during lactation period. Laser-induced breakdown spectroscopy offers special advantages in comparison to the other conventional analytical techniques. Specifically, LIBS is a straightforward technique that can be used in situ to provide qualitative analytical information in few minutes for the samples under investigation without preparation processes. The samples studied in the current work were maternal milk samples collected during the first 3 months of lactation (not colostrum milk) and samples from six different types of commercially available infant formulas. The samples' elemental composition has been compared with respect to the relative abundance of the elements of nutrition importance, namely Mg, Ca, Na, and Fe using their spectral emission lines in the relevant LIBS spectra. In addition, CN and C2 molecular emission bands in the same spectra have been studied as indicators of proteins content in the samples. The obtained analytical results demonstrate the higher elemental contents of the maternal milk compared with the commercial formulas samples. Similar results have been obtained as for the proteins content. It has been also shown that calcium and proteins have similar relative concentration trends in the studied samples. This work demonstrates the feasibility of adopting LIBS as a fast, safe, less costly technique evaluating qualitatively the nutrients content of both maternal and commercial milk samples.

  10. High lib mRNA expression in breast carcinomas.

    PubMed

    Satoh, Kazuki; Hata, Mitsumi; Yokota, Hiroshi

    2004-06-30

    Lib, first identified as a novel beta-amyloid responsive gene in rat astrocytes, has an extracellular domain of 15 leucine-rich repeats (LRRs) followed by a transmembrane domain and a short cytoplasmic region. It is a distinctly inducible gene and is thought to play a key role in inflammatory states via the LRR extracellular motif, an ideal structural framework for protein-protein and protein-matrix interactions. To evaluate potential roles of Lib, we screened various tumors for Lib expression. Lib mRNA expression was high and uniquely expressed in breast tumor tissues, compared to paired normal breast tissues. Lib mRNA was localized in the ductal carcinoma cells and Lib protein displayed a homophilic association on the surface of cultured cells. These data suggest that Lib may play a role in the progression of breast carcinomas and may be a diagnostic marker for breast tumors.

  11. 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…

  12. 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.

  13. 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.

  14. Structural characterization of slightly boron-deficient LiB, LiB0.9 and LiB0.8, under pressure.

    PubMed

    Suarez-Alcubilla, Ainhoa; Gurtubay, Idoia G; Bergara, Aitor

    2014-11-26

    Results of computational investigations of two slightly boron-deficient lithium borides, LiB(0.9) and LiB(0.8), under pressure are reported. Structure predictions based on particle swarm optimization reveal that at low pressure both compositions adopt chain structures, as stoichiometric 1 : 1 LiB. With increasing pressure both undergo phase transitions to layered arrangements. The evolution of the structural parameters of these stoichiometries as a function of pressure and the results obtained from the enthalpies indicate that boron-deficient structures are more favoured than 1 : 1 LiB, even at zero pressure. Moreover, as pressure is increased a larger deficiency in B seems to be favoured.

  15. 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

    2015-06-04

    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

  16. 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.

  17. 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

  18. LIBS using dual- and ultra-short laser pulses.

    PubMed

    Angel, S M; Stratis, D N; Eland, K L; Lai, T; Berg, M A; Gold, D M

    2001-02-01

    Pre-ablation dual-pulse LIBS enhancement data for copper, brass and steel using ns laser excitation are reported. Although large enhancements are observed for all samples, the magnitude of the enhancement is matrix dependent. Whereas all of the dual-pulse studies used ns laser excitation we see interesting effects when using ps and fs laser excitation for single-pulse LIBS. LIBS spectra of copper using 1.3 ps and 140 fs laser pulses show much lower background signals compared to ns pulse excitation. Also, the atomic emission decays much more rapidly with time. Because of relatively low backgrounds when using ps and fs pulses, non-gated detection of LIBS is shown to be very effective. The plasma dissipates quickly enough using ps and fs laser pulses, that high pulse rates, up to 1,000 Hz, are effective for increasing the LIBS signal, for a given measurement time. Finally, a simple near-collinear dual-pulse fiber-optic LIBS probe is shown to be useful for enhanced LIBS measurements.

  19. 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.

  20. 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.

  1. 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.

  2. Effects of sediment-associated copper to the deposit-feeding snail, Potamopyrgus antipodarum: a comparison of Cu added in aqueous form or as nano- and micro-CuO particles.

    PubMed

    Pang, Chengfang; Selck, Henriette; Misra, Superb K; Berhanu, Deborah; Dybowska, Agnieszka; Valsami-Jones, Eugenia; Forbes, Valery E

    2012-01-15

    Increasing use of engineered nanoparticles (NPs) is likely to result in release of these particles to the aquatic environment where the NPs may eventually accumulate in sediment. However, little is known about the potential ecotoxicity of sediment-associated engineered NPs. We here consider the case of metal oxide NPs using CuO to understand if the effects of NPs differ from micron-sized particles of CuO and aqueous Cu (CuCl₂). To address this issue, we compared effects of copper added to the sediment as aqueous Cu, nano- (6 nm) and micro- (<5 μm) CuO particles on the deposit-feeding snail, Potamopyrgus antipodarum. Effects were assessed as mortality, specific growth rate, feeding rate, reproduction, and bioaccumulation after 8 weeks of exposure to nominal concentrations of 0, 30, 60, 120 and 240 μg Cu/g dry weight sediment. The results demonstrate that copper added to sediment as nano-CuO had greater effects on growth, feeding rate, and reproduction of P. antipodarum than copper added as micro-CuO or aqueous Cu. P. antipodarum accumulated more copper in the nano-CuO treatment than in aqueous Cu or micro-CuO treatments, indicating that consideration of metal form may be important when assessing risks of metals to the aquatic environment.

  3. 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.

  4. 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.

  5. The effects of food deprivation, nutritive and non-nutritive feeding and wheel running on gastric stress ulcers in rats.

    PubMed

    Yi, I; Stephan, F K

    1998-01-01

    Feeding and housing conditions that induce gastric lesions were investigated. Rats were housed in activity wheels or in hanging cages and exposed to food deprivation, ad lib cellulose or 6 g of cellulose per day for 5 days. Food-deprived rats in both housing conditions had ulcers in the rumen but many rats also had mucosal ulcers. Cellulose prevented rumenal ulcers but produced a tendency toward more severe mucosal ulcers. Ulcers in wheel-housed rats were somewhat larger but the difference was not significant. In a second experiment, rats were fed 6 g/day laboratory chow or 6 g/day chow + ad lib cellulose until b.wt. reached a preset criterion. On the average, about 10 days on the feeding regimen were required to induce ulcers in these groups. None of the rats had rumenal ulcers. Mucosal ulcers were reliably larger in rats that received cellulose in addition to 6 g of chow. There was no difference in ulcer area between wheel-housed and cage-housed rats. The results indicate that solid bulk, regardless of its caloric value or amount, protects the nonglandular stomach whereas noncaloric bulk tends to aggravate ulcers in the glandular stomach. A small amount of chow delays the rate of b.wt. loss and consequently ulcer formation. Furthermore, wheel running is not necessary to produce mucosal ulcers when food intake is insufficient to maintain b.wt. and b.wt. at sacrifice seems to be a good predictor of ulcer formation.

  6. Effects of Feeding Milk Replacer Ad Libitum or in Restricted Amounts for the First Five Weeks of Life on the Growth, Metabolic Adaptation, and Immune Status of Newborn Calves

    PubMed Central

    Schäff, Christine T.; Gruse, Jeannine; Maciej, Josefine; Mielenz, Manfred; Wirthgen, Elisa; Hoeflich, Andreas; Schmicke, Marion; Pfuhl, Ralf; Jawor, Paulina; Stefaniak, Tadeusz

    2016-01-01

    The pre-weaning period is critical for calf health and growth, and intensive milk feeding programs may assist postnatal development by improving body growth and organ maturation. The aim of the present work was to study the effects of ad libitum milk replacer (MR) feeding on the growth, metabolic adaptation, health, and immune status of newborn calves. Twenty-eight newborn Holstein and Holstein x Charolais crossbred calves were fed ad libitum (ADLIB) or in restricted amounts (6 liters per day; RES) during the first five weeks of life. The MR intake in the ADLIB treatment was gradually reduced at weeks 6 and 7, and all calves then received 6 liters of MR per day until day 60. Blood samples were collected to measure the plasma concentrations of metabolites, insulin, insulin-like growth factor (IGF)-I and IGF binding proteins (IGFBP), immunoglobulins, and acute phase proteins. The expression of mRNA associated with both the somatotropic axis and gluconeogenic enzymes was measured in the liver on day 60. Intensive feeding improved MR intake and growth in ADLIB without influencing concentrate intake. Carcass weight, perirenal fat, and muscle mass were greater in ADLIB. Plasma concentrations of glucose, triglycerides, insulin, and IGF-I were greater, whereas plasma concentrations of β-hydroxybutyrate, total protein, albumin, urea, IGFBP-2 and -4, and fibrinogen were lower at distinct time points in ADLIB. The hepatic mRNA expression of cytosolic phosphoenolpyruvate carboxykinase was greater in ADLIB. Most metabolic and endocrine differences occurred during the MR feeding period, but a slightly greater concentrate intake was associated with increased plasma IGF-I and insulin at the end of the study. The immune and health status of the calves were not affected by MR feeding. However, increased plasma fibrinogen in the RES group suggested differences in the acute phase response. PMID:28036351

  7. A cosmology forecast toolkit — CosmoLib

    NASA Astrophysics Data System (ADS)

    Huang, Zhiqi

    2012-06-01

    The package CosmoLib is a combination of a cosmological Boltzmann code and a simulation toolkit to forecast the constraints on cosmological parameters from future observations. In this paper we describe the released linear-order part of the package. We discuss the stability and performance of the Boltzmann code. This is written in Newtonian gauge and including dark energy perturbations. In CosmoLib the integrator that computes the CMB angular power spectrum is optimized for a l-by-l brute-force integration, which is useful for studying inflationary models predicting sharp features in the primordial power spectrum of metric fluctuations. As an application, CosmoLib is used to study the axion monodromy inflation model that predicts cosine oscillations in the primordial power spectrum. In contrast to the previous studies by Aich et al. and Meerburg et al., we found no detection or hint of the osicllations. We pointed out that the CAMB code modified by Aich et al. does not have sufficient numerical accuracy. CosmoLib and its documentation are available at http://www.cita.utoronto.ca/~zqhuang/CosmoLib

  8. Effects of feeding regimen, fiber inclusion, and crude protein content of the diet on performance and egg quality and hatchability of eggs of broiler breeder hens.

    PubMed

    Mohiti-Asli, M; Shivazad, M; Zaghari, M; Rezaian, M; Aminzadeh, S; Mateos, G G

    2012-12-01

    A 12-wk experiment was conducted to study the effects of feeding regimen, inclusion of a fiber source, and CP content of the diet on performance of broiler breeder hens. In total, 360 hens and 60 males, 43 wk of age, were assigned to 60 floor pens (6 hens and 1 male each). There were 12 treatments arranged factorially with 2 feeding regimens [restricted (R) and liberal feeding (close to ad libitum consumption; LIB)], 3 sources of fiber (0, 3% inulin, and 3% cellulose), and 2 levels of CP (14.5 and 17.4%). No interactions among main effects were observed for any of the traits studied, and therefore, only main effects are presented. Body weight, liver weight, and abdominal fat weight were higher (P < 0.001) for the LIB than for the R-fed hens. However, egg production (P < 0.001), fertility index (P < 0.05), and percentage of hatch (P < 0.01) were lower for LIB than for R hens. The weights of ovaries (P < 0.05) and the size of the first preovulatory follicle (P < 0.05) were higher for the LIB than for the R hens. Also, egg yolk, egg weight, and BW of the hatching chicks were higher (P < 0.001) for the LIB hens. The inclusion of a fiber source in the diet decreased (P < 0.05) feed intake, BW gain, absolute liver and abdominal fat weight, and egg yolk weight, with effects being more pronounced (P < 0.05) with cellulose than with inulin. Hens fed additional fiber produced more (P < 0.05) eggs that were more fertile (P < 0.05) than control hens. Crude protein content of the diet did not affect hen performance but reduced (P < 0.01) the relative weight of the liver, ovary, and abdominal fat. It is concluded that the inclusion of inulin or cellulose in the diet improved hen performance and that an increase in dietary CP reduced obesity in broiler breeder hens.

  9. [The LIBS experiment condition optimization of alloy steel].

    PubMed

    Shao, Yan; Gao, Xun; Du, Chuang; Zhao, Zhen-Ming; Chen, Wei-Yu; Hao, Zuo-Qiang; Sun, Chang-Kai; Lin, Jing-Quan

    2013-02-01

    Laser induced plasma spectroscopy of alloy steel was produced by Nd : YAG pulsed laser at 1 064 nm, and the spectral signal was detected by high resolution and width controlled ICCD. Several Fe atomic spectral lines such as 404.581, 414.387, 427.176 and 438.355 nm were chosen for analysis, and the effects of different experimental parameters on LIBS spectral signal intensity were investigated. It is shown that the experimental parameters such as pulse energy, laser focus location and laser delay time have great influence on the LIBS signal. LIBS signals with high spectral intensity and signal-background ratio (SBR) as well as the optimum experiment conditions were obtained by optimizing these experiment parameters so as to make composition analysis of the alloy steel.

  10. 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

  11. Outburst of the Cataclysmic Variable 1514-24 GW Lib

    NASA Astrophysics Data System (ADS)

    Templeton, Matthew R.

    2007-04-01

    The cataclysmic variable 1514-24 GW Lib is in outburst (Rod Stubbings, Drouin, Victoria, Australia, visual magnitude 13.8, 2007 April 12.4938 UT), the first outburst observed since its discovery on 1983 August 10 UT. V-band time series photometry and visual observations are urgently requested for GW Lib [the brightest of the accreting pulsating white dwarf systems; the outburst provides the opportunity to see how pulsations change with temperature, according to Dr. Paula Szkody, University of Washington]. Data reported to the AAVSO may be found at www.aavso.org.

  12. 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.

  13. Accreting Pulsators Gw Lib and V455 and after Superoutburst

    NASA Astrophysics Data System (ADS)

    Szkody, Paula

    Two cataclysmic variables containing pulsating white dwarfs underwent rare outbursts in 2007 (GW Lib and V455 And). As we know outbursts heat the white dwarfs by more than 10,000K and they gradually cool to their quiescent temperatures over the course of about 3 years, these two objects present the first unique opportunity to follow the pulsation spectrum of a white dwarf as it cools on much more rapid timescales than evolutionary ones for single white dwarfs. As these 2 objects cool, they should re-enter their instability strips and we can witness changes in the driving mechanism and detect modes that are excited by the T changes. Our 2008 ground-based data on GW Lib showed an intermittent new pulsation at a longer period than at quiescence. The data in 2010 will be the critical 3rd year and will be combined with our DOT and Cycle 4,5 GI observations to determine the long term cooling of GW Lib. Similar information will be obtained for V455 And. The higher pulse amplitude in UV vs optical and the time-tag mode means that GALEX can provide optimum data over the optical. Data on both systems will provide an important contrast in how the white dwarfs react to an outburst, as GW Lib at quiescence has a hot white dwarf far outside the normal instability strip for non-accreting white dwarfs, while V455 And is cool and inside this strip.

  14. The LIBS Internet Access Software: An Overview and Evaluation.

    ERIC Educational Resources Information Center

    Stanton, Deidre E.; Hooper, Todd

    1992-01-01

    Describes and evaluates LIBS Internet Access Software (also called Sonoma Software), which offers automatic Telnet connection to remote library catalogs, databases, information services, campuswide information services, and other wide-area information access tools. Instructions for obtaining and installing the software are given, and a comparison…

  15. A Combined Remote LIBS and Raman Spectroscopic Study of Minerals

    NASA Technical Reports Server (NTRS)

    Hubble, H. W.; Ghosh, M.; Sharma, S. K.; Horton, K. A.; Lucey, P. G.; Angel, S. M.; Wiens, R. C.

    2002-01-01

    In this paper, we explore the use of remote LIBS combined with pulsed-laser Raman spectroscopy for mineral analysis at a distance of 10 meters. Samples analyzed include: carbonates (both biogenic and abiogenic), silicates, and sulfates. Additional information is contained in the original extended abstract.

  16. 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.,…

  17. 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);…

  18. Computer methods for ITER-like materials LIBS diagnostics

    NASA Astrophysics Data System (ADS)

    Łepek, Michał; Gąsior, 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.

  19. Questioning LibQUAL+[TM]: Expanding Its Assessment of Academic Library Effectiveness

    ERIC Educational Resources Information Center

    Edgar, William B.

    2006-01-01

    This article examines LibQUAL+[TM]'s instrument, fundamental assumption, and research approach and proposes a functional/technical model of academic library effectiveness. This expanded view of library effectiveness complements LibQUAL+[TM], emphasizing it to be dependent upon users' experience of service delivery, as LibQUAL+[TM] recognizes.…

  20. Influence of Atmospheric Pressure and Composition on LIBS

    SciTech Connect

    Hatch, Jeremy J.; Scott, Jill R.; Effenberger, A. J. Jr.

    2014-03-01

    Most LIBS experiments are conducted at standard atmospheric pressure in air. However, there are LIBS studies that vary the pressure and composition of the gas. These studies have provided insights into fundamentals of the mechanisms that lead to the emission and methods for improving the quality of LIBS spectra. These atmospheric studies are difficult because the effects of pressure and gas composition and interconnected, making interpretation of the results difficult. The influence of pressures below and above 760 Torr have been explored. Performing LIBS on a surface at reduced pressures (<760 Torr) can result in enhanced spectra due to higher resolution, increased intensity, improved signal-to-noise (S/N), and increased ablation. Lower pressures produce increased resolution because the line width in LIBS spectra is predominantly due to Stark and Doppler broadening. Stark broadening is primarily caused from collisions between electrons and atoms, while Doppler broadening is proportional to the plasma temperature. Close examination using a high resolution spectrometer reveals that spectra show significant peak broadening and self-absorption as pressures increase, especially for pressures >760 Torr. During LIBS plasma expansion, energy is lost to the surrounding atmosphere, which reduces the lifetime of the laser plasma. Therefore, reducing the pressure increases the lifetime of the plasma, allowing more light from the laser plasma to be collected; thus, increasing the observed signal intensity. However, if pressures are too low (<10 Torr), then there is a steep drop in LIBS spectral intensity. This loss in intensity is mostly due to a disordered plasma that results from the lack of sufficient atmosphere to provide adequate confinement. At reduced pressures, the plasma expands into a less dense atmosphere, which results in a less dense shock wave. The reduced density in the shock wave results in reduced plasma shielding, allowing more photons to reach the sample

  1. Prolonged oral cyanide effects on feed intake, growth rate and blood parameters in rabbits.

    PubMed

    Avais, Muhammad; Khan, Muhammad Sarwar; Khan, Muhammad Arif; Ashraf, Kamran; Khan, Jawaria Ali; Hameed, Sajid

    2014-07-01

    Twelve adult rabbits bred locally were divided into two equal groups of 6; experimental and control groups. Rabbits in the experimental group were orally dosed with KCN at 3mg/kg body weight for 40 consecutive days. Members in control group were given placebo (distilled water) for the same period. Animals in both groups were offered feed at 90gm/kg/day while ample drinking water was available ad lib. Feed consumption and body weight of rabbits in both the groups were recorded. Blood samples were also drawn to determine various hematological parameters. Statistical analysis revealed a non-significant difference of total and daily feed intakes in rabbits of experimental and control groups. Whereas the feed efficiency of rabbits in the experimental group were significantly reduced (P<0.05) compared to controls. Likewise a significant decrease in body weight gain of rabbits in experimental group (P<0.05) was observed. A non-significant difference (P>0.05) was observed in leukocyte count, differential leukocyte count and platelets of rabbits in both the groups. Erythrocyte count, hemoglobin concentration, packed cell volume and mean corpuscular hemoglobin were significantly decreased in treated rabbits. It was concluded that chronic cyanide intake had a deleterious effect on feed efficiency, growth rate and blood components of rabbits.

  2. Comparative effects of added sodium chloride, ammonium chloride, or potassium bicarbonate in the drinking water of broilers, and feed restriction, on the development of the ascites syndrome.

    PubMed

    Shlosberg, A; Bellaiche, M; Berman, E; Ben David, A; Deeb, N; Cahaner, A

    1998-09-01

    A hypothesis that the ionic composition of drinking water might affect development of the ascites syndrome in broilers was investigated in two trials. The first trial comprised four groups of 650 male chicks. A control treatment was normal tap water and the other three treatments comprised the addition to the tap water of 1,000 mg/L sodium as NaCl, 5,000 mg/L NH4Cl, or 5,000 mg/L KHCO3, supplied from age 2 to 47 d. At Day 28, equally sized subsets of these groups were moved to individual cages, where they received a severe exposure to ambient cold. The development of the ascites syndrome was monitored by measurements of hematocrit and arterial blood oxygen saturation (PaO2) by oximetry, body weight, and examination of dead birds for cause of death. Mortality from ascites in cold-exposed birds from Days 28 to 47 was 28, 48, 40, and 16% in the tap water, NaCl, NH4Cl, and KHCO3 groups, respectively; only the NaCl mortality was significantly different from the tap water mortality. The KHCO3 treatment increased PaO2 (compared with tap water treatment) at Day 28 by 5.5% and at Day 35 by 10.5%, but not at Day 42. The KHCO3 caused a reduction in body weight, which was 13% less than the tap water group at Day 42, probably due to a chronic toxicity. The second trial specifically examined the same parameters with lower water levels of KHCO3 (3,000 and 1,000 mg/L), in comparison to a 10% feed restriction protocol, in order to clarify whether the increased PaO2 was due to a specific effect of the KHCO3 or was a metabolic manifestation of a reduced growth rate. The 3,000 mg/L KHCO3 treatment had no effect on PaO2, but the 1,000 mg/L treatment augmented PaO2 by 5.3% at Day 35 (but not at Days 28 or 42), without reducing the final body weight. The feed restriction group showed an elevated PaO2 of 5.4% at Day 35 (but not at Days 28 or 42), with no reduction in the final body weight. The inclusion of 1,000 mg/L of KHCO3 into the drinking water of broilers or a temporary 10% feed

  3. Different milk feeding intensities during the first 4 weeks of rearing dairy calves: Part 2: Effects on the metabolic and endocrine status during calfhood and around the first lactation.

    PubMed

    Kesser, J; Korst, M; Koch, C; Romberg, F-J; Rehage, J; Müller, U; Schmicke, M; Eder, K; Hammon, H M; Sadri, H; Sauerwein, H

    2017-04-01

    Feeding dairy calves at high intensity has been demonstrated to increase milk yield in later life. We investigated the effect of 3 different feeding regimens in the preweaning period on the metabolic and endocrine status during calfhood and in heifers at the onset of the first lactation. In trial 1, 57 German Holstein calves were allocated to 3 different feeding groups: milk replacer restricted to 6.78 kg/calf per day, 11.5% solids (MR-res, n = 20), milk replacer 13.8% solids, ad libitum (MR-ad lib, n = 17), and whole milk ad libitum (WM-ad lib, n = 20). All calves received ad libitum colostrum for 3 d postnatal (p.n.). From d 4 to 27, all calves were fed according to their respective feeding regimen, resulting in average intakes of 6.38, 9.25, and 9.47 kg/d in MR-res, MR-ad lib, and WM-ad lib, respectively. Thereafter, all calves were fed according to the MR-res regimen until weaning at d 55 (gradually until d 69 p.n.). Blood samples were collected on d 0 before colostrum intake and on d 1, 3, 11, 22, 34, 43, 52, 70, 90, and 108 p.n. Liver biopsies were taken on d 19 and 100, and on d 22, 52, and 108 p.n. intravenous glucose tolerance tests were performed. The male calves (n = 8 to 10 per group) underwent also an insulin tolerance test on d 24, 54, and 110 p.n. The females (n = 28) from trial 1 were further reared and bred as common practice, and were enrolled in trial 2 when beginning the last trimester of pregnancy. Blood samples were collected monthly antepartum starting 91 d before calving and weekly (0-70 d) postpartum. Trial 1 was subdivided into 4 phases (P): P0 (d 0-1), P1 (d 2-27), P2 (d 28-69), and P3 (d 70-110 p.n.). In trial 1, the leptin and adiponectin concentrations increased with colostrum intake. Differences in fatty acids, insulin, adiponectin, revised quantitative insulin sensitivity check index (RQUICKI), and variables from the glucose tolerance tests were largely limited to P1. The MR-res group had greater RQUICKI and fatty acid values, and

  4. Feeding frequency and appetite in lean and obese prepubertal children.

    PubMed

    Mehra, Rinku; Tsalikian, Eva; Chenard, Catherine A; Zimmerman, M Bridget; Sivitz, William I

    2011-03-01

    To determine the effect of feeding frequency on appetite in normal weight (NW) and obese (OB) prepubertal children, we carried out a prospective, randomized interventional study of 18 NW and 17 OB children ages 6-10. Children received three or five feedings in random order on separate days. Total calories, carbohydrate, protein, and fat composition on each day were equal. Two hours following the last feeding, children were offered ice cream ad lib. The major outcome variable was kilocalories ice cream consumed. A visual analog scale to assess fullness was also administered before consumption of ice cream. We observed that OB children consumed 73.0 ± 37.4 kcal more after five feedings than after three feedings whereas the NW children consumed 47.1 ± 27.8 kcal less. There was significant interaction between meal pattern and weight group indicating that this change in ice cream consumption differed significantly between groups (P = 0.014 by two-factor analysis). Ice cream intake/kg was less in OB compared to NW subjects (P = 0.012). Fullness ratings before ice cream did not differ by meal pattern or weight group. However, pre-ice cream fullness predicted ice cream intake in NW but not OB children. In summary, OB and NW children differed in appetite response to meal frequency. Our data suggest that: (i) satiety in OB children is related more to proximity of calories (larger supper) than to antecedent distribution of calories and; (ii) NW children may be more prone to restrict intake based on subjective fullness.

  5. 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.

  6. B[e] Properties in the Spectrum of 48 Lib

    NASA Astrophysics Data System (ADS)

    Ismailov, N. Z.; Maharramov, Y. M.

    2017-02-01

    Temporal variations of the Hα, Hβ, He I λ5876 Å, NaI D1, D2 lines, and DIBs at λ5780 and 5797 Å in the spectrum of the Be star 48 Lib are investigated and the presence of the [O I] λ 6300, 6363 Å lines is suspected. We also found additional moving components in the Na I D line profiles.

  7. Review of LIBS application in nuclear fusion technology

    NASA Astrophysics Data System (ADS)

    Li, Cong; Feng, Chun-Lei; Oderji, Hassan Yousefi; Luo, Guang-Nan; Ding, Hong-Bin

    2016-12-01

    Nuclear fusion has enormous potential to greatly affect global energy production. The next-generation tokamak ITER, which is aimed at demonstrating the feasibility of energy production from fusion on a commercial scale, is under construction. Wall erosion, material transport, and fuel retention are known factors that shorten the lifetime of ITER during tokamak operation and give rise to safety issues. These factors, which must be understood and solved early in the process of fusion reactor design and development, are among the most important concerns for the community of plasma-wall interaction researchers. To date, laser techniques are among the most promising methods that can solve these open ITER issues, and laser-induced breakdown spectroscopy (LIBS) is an ideal candidate for online monitoring of the walls of current and next-generation (such as ITER) fusion devices. LIBS is a widely used technique for various applications. It has been considered recently as a promising tool for analyzing plasma-facing components in fusion devices in situ. This article reviews the experiments that have been performed by many research groups to assess the feasibility of LIBS for this purpose.

  8. The contrasting effects of ad libitum and restricted feeding of a diet very high in saturated fats on sex ratio and metabolic hormones in mice.

    PubMed

    Alexenko, Andrei P; Mao, Jiude; Ellersieck, Mark R; Davis, Angela M; Whyte, Jeffrey J; Rosenfeld, Cheryl S; Roberts, R Michael

    2007-10-01

    Skewing of the sex ratio towards males occurs among pups born to mice fed a very high saturated fat (VHF) diet. In the present study, we tested whether the fat content of the VHF diet rather than the number of calories consumed is responsible for this effect. Eight-week-old NIH Swiss mice were placed on the VHF diet either ad libitum (VHF) or in a restricted manner (VHF-R). The VHF-R mice gained weight at a similar rate to controls fed a standard chow diet. Mice were bred at 15 wk and subsequently at 26 wk and 35 wk of age. Overall, the VHF, VHF-R, and control groups delivered 244, 242, and 274 pups, respectively, with male proportions of 0.60, 0.43, and 0.48, respectively. The pup sex ratios of the VHF group (favoring males) and VHF-R group (favoring females) each differed from 0.5 (P < 0.01). The sex ratios also differed (P < 0.0001) between the VHF and control groups, and between the VHF and VHF-R groups. Within the diet groups, maternal body weight had no effect on sex ratio. Serum leptin concentrations among the dams were similar in the VHF and VHF-R groups but higher than in the control group, while the IGF1 and corticosterone levels were comparable in all three groups. Therefore, the atypical sex ratios of offspring born to dams on the VHF diet seem to be influenced by the amount of fat consumed. Since males fed the VHF diet had neither more Y-sperm nor sired more sons than daughters, the dietary effects are manifested exclusively through the female.

  9. 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.

  10. Hairy AdS solitons

    NASA Astrophysics Data System (ADS)

    Anabalón, Andrés; Astefanesei, Dumitru; Choque, David

    2016-11-01

    We construct exact hairy AdS soliton solutions in Einstein-dilaton gravity theory. We examine their thermodynamic properties and discuss the role of these solutions for the existence of first order phase transitions for hairy black holes. The negative energy density associated to hairy AdS solitons can be interpreted as the Casimir energy that is generated in the dual filed theory when the fermions are antiperiodic on the compact coordinate.

  11. Mercury Amalgam Diffusion in Human Teeth Probed Using Femtosecond LIBS.

    PubMed

    Bello, Liciane Toledo; da Ana, Patricia Aparecida; Santos, Dário; Krug, Francisco José; Zezell, Denise Maria; Vieira, Nilson Dias; Samad, Ricardo Elgul

    2017-01-01

    In this work the diffusion of mercury and other elements from amalgam tooth restorations through the surrounding dental tissue (dentin) was evaluated using femtosecond laser-induced breakdown spectroscopy (fs-LIBS). To achieve this, seven deciduous and eight permanent extracted human molar teeth with occlusal amalgam restorations were half-sectioned and analyzed using pulses from a femtosecond laser. The measurements were performed from the amalgam restoration along the amalgam/dentin interface to the apical direction. It was possible to observe the presence of metallic elements (silver, mercury, copper and tin) emission lines, as well as dental constituent ones, providing fingerprints of each material and comparable data for checking the consistence of the results. It was also shown that the elements penetration depth values in each tooth are usually similar and consistent, for both deciduous and permanent teeth, indicating that all the metals diffuse into the dentin by the same mechanism. We propose that this diffusion mechanism is mainly through liquid dragging inside the dentin tubules. The mercury diffused further in permanent teeth than in deciduous teeth, probably due to the longer diffusion times due to the age of the restorations. It was possible to conclude that the proposed femtosecond-LIBS system can detect the presence of metals in the dental tissue, among the tooth constituent elements, and map the distribution of endogenous and exogenous chemical elements, with a spatial resolution that can be brought under 100 µm.

  12. LIBS identification of pigments from Aula Leopoldina vault

    NASA Astrophysics Data System (ADS)

    Ostrowski, R.; Skrzeczanowski, W.; Marczak, J.; Sarzynski, A.

    2009-07-01

    Aula Leopoldina is the most representative, baroque hall in Wroclaw University. In 2008, LIBS measurements of paintings layers of Aula vault were done. LIBS spectra permitted identification of mineral pigments used for specific colors of painting layers. This identification could not be unambiguous in each case since simultaneous occurrence of elements that could be components of different pigments of the same color was observed in some samples. For example, in some red samples the presence of aluminum and iron was stated, and hence red ochre or Mars red could be used as a pigment. In other samples the cinnabar can be additionally responsible for red color. Similar problems were observed in case of blue pigments, where existence of copper may show that azurite was used, but the presence of aluminum, sodium, silicon and iron can point to application of ultramarine, Egyptian or Prussian blues. The greatest difficulties occurred during identification of white pigments. Because of presence of barium, zinc, lead and titanium, the potential pigments might be lithopone, barite, zinc white, lead white or titanium white. Final choice of the pigment is determined by the time of last renovation and this points out that the zinc white was used.

  13. Development of a portable low-cost LIBS system

    NASA Astrophysics Data System (ADS)

    Ormachea, O.; Urquidi, O.; Casazola, D.

    2013-11-01

    This article reports the construction of a portable, low-cost LIBS (Light Induced Breakdown Spectroscopy) system for use in the Bolivian mining industry for the qualitative and quantitative analysis of the composition of mineral samples. The device consists of a portable laser, a medium-resolution spectrometer and an optomechanical light collection system. The laser developed for the device is a YAG:Nd+++ with an estimated power output of 10 MW/cm2. Weighing approximately 3 kg and powered by lithium ion batteries, it is easily carried and can be used in remote locations. The spectrometer has a resolution of 0.3 nm allowing the detection fine spectral features, while its range of 80 nm is broad enough to simultaneously show many of the principal spectral lines of the element of interest. A monochromatic CCD camera was used as the detector of the spectrometer and was fitted with an external trigger to coordinate the camera frames with the firing of the laser. The light emitted by the plasma is collected with a photographic objective and is transmitted to the spectrometer via a fiber optics cable. A mechanical system was incorporated to make, both the laser beam and the receptor positionable. In the preliminary tests of the prototype, a LIBS spectrum of a Bolivian copper coin was obtained. Analysis showed that the spectral lines obtained coincide with those of a copper reference spectrum and demonstrate the capacity of the device to perform qualitative analysis of materials.

  14. LIBS and Raman spectroscopic investigation of historical copper alloy objects

    NASA Astrophysics Data System (ADS)

    Żmuda-Trzebiatowska, Iwona; Śliwiński, Gerard

    2015-01-01

    Results of spectroscopic investigation of the historical copper and copper alloy objects covered by patina and surface contamination are reported and discussed in this work. For analysis of the surface layers (bulk material, primer/grounding, patina and atmospheric contamination) the Laser Induced Breakdown (LIBS), Raman and X-ray fluorescence (XRF) spectroscopic techniques are used. Useful data on chemical structure and composition are obtained from stratigraphic analysis performed by a stepwise layer penetration with successive laser pulses. The LIBS, XRF and Raman spectra confirm the presence of patina and contamination layers of the compositions influenced by the atmospheric environment. The elemental composition reveals in the case of the original copper substrate the presence of Cu with traces of Ag and Sb, and of impurities Fe and Pb, while objects made of copper alloys (brass) show different Zn/Cu ratios greater than 20% in all cases and admixtures of Sn and Pb. Consistent results are obtained from the elemental and Raman data indicating presence of the antlerite (Cu3(OH)4SO4), carbon and microcrystalline calcite which are ascribed to patina, surface contamination (atmospheric soot) and primer layers, respectively.

  15. 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...

  16. 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…

  17. "Zones of Tolerance" in Perceptions of Library Service Quality: A LibQUAL+[TM] Study.

    ERIC Educational Resources Information Center

    Cook, Colleen; Heath, Fred M.; Thompson, Bruce

    2003-01-01

    One of the two major ways of interpreting LibQUAL+[TM] data involves placing perceived service quality ratings within "zones of tolerance" defined as the distances between minimally-acceptable and desired service quality levels. This study compared zones of tolerance on the 25 LibQUAL+[TM] items across undergraduate, graduate student and…

  18. 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.…

  19. 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…

  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. LibQUAL+[TM]: A Methodological Suite; Reliability and Structure of LibQUAL+[TM] Scores: Measuring Perceived Library Service Quality; Score Norms for Improving Library Service Quality: A LibQUAL+[TM] Study; ARL Index and Other Validity Correlates of LibQUAL+[TM] Scores.

    ERIC Educational Resources Information Center

    Heath, Fred M.; Thompson, Bruce; Cook, Colleen; Thompson, Russel L.; Kyrillidou, Martha

    2002-01-01

    Includes four articles that discuss LibQUAL+[TM], a collaborative effort of the Association of Research Libraries and Texas A&M University responding to the need for greater accountability in measuring the delivery of library services to research library users. Discusses the reliability of LibQUAL+[TM] scores in measuring perceived library…

  2. Laboratory Exploration of Organic and Inorganic Carbon by Laser-induced Breakdown Spectroscopy (LIBS): Relevance for Planetary Astrobiology Missions

    NASA Astrophysics Data System (ADS)

    Blank, J. G.; Clegg, S. M.; Barefield, J. E.; McKay, C. P.; Wiens, R. C.

    2010-03-01

    We used LIBS and chemometric analysis to distinguish between organic and inorganic carbon in various samples (igneous rocks, carbonates, and kerogen-rich fertilizers), demonstrating the potential for ChemCam LIBS as an astrobiology tool for MSL.

  3. SeqLib: a C ++ API for rapid BAM manipulation, sequence alignment and sequence assembly.

    PubMed

    Wala, Jeremiah; Beroukhim, Rameen

    2017-03-01

    We present SeqLib, a C ++ API and command line tool that provides a rapid and user-friendly interface to BAM/SAM/CRAM files, global sequence alignment operations and sequence assembly. Four C libraries perform core operations in SeqLib: HTSlib for BAM access, BWA-MEM and BLAT for sequence alignment and Fermi for error correction and sequence assembly. Benchmarking indicates that SeqLib has lower CPU and memory requirements than leading C ++ sequence analysis APIs. We demonstrate an example of how minimal SeqLib code can extract, error-correct and assemble reads from a CRAM file and then align with BWA-MEM. SeqLib also provides additional capabilities, including chromosome-aware interval queries and read plotting. Command line tools are available for performing integrated error correction, micro-assemblies and alignment.

  4. Added Sugars

    MedlinePlus

    ... need sugar to function properly. Added sugars contribute zero nutrients but many added calories that can lead to extra pounds or even obesity, thereby reducing heart health. If you think of your daily calorie needs as a budget, you want to “spend” ...

  5. 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,…

  6. Steroid hormone excretion is enhanced by sucrose feeding to rats

    SciTech Connect

    Kruger, T.C.; Hsu, H.; Saunders, J.P.; Kim, S.S.; Given-Proctor, J.; Ahrens, R.A.

    1986-03-01

    The hypothesis tested was that feeding rats sucrose rather than invert sugar (50:50 mixture of glucose and fructose) or cornstarch would result in a more rapid excretion of intravenously injected 1,2-/sup 3/H aldosterone or 1,2,6,7-/sup 3/H cortisol. The three carbohydrate sources provided 45% of dietary energy when fed, respectively, to one of three groups of 10 male, Sprague Dawley rats. After 4 or 8 weeks of ad lib feeding of the three diets 5 ..mu..CI of /sup 3/H-labeled hormones were injected intravenously and % recovery in urine and feces was measured for 4 days by liquid scintillation counting. Nearly 90% of the /sup 3/H injected as 1,2-/sup 3/H aldosterone was recovered over 4 days in the excreta of the sucrose fed rats. This recovery of /sup 3/H from aldosterone was significantly greater (P < 0.01) than when invert sugar (65%) or cornstarch (60%) were fed. The recovery of /sup 3/H from intravenously injected 1,2,6,7-/sup 3/H cortisol followed a similar pattern. The authors anticipate that the excretion of all metabolic end products and xenobiotics excreted as glucuronides would be enhanced by sucrose feeding. Oxocarbonium ions from the glucose portion of sucrose digestion in the mammalian small intestine are thought to compete with oxocarbonium ions from the glucuronic acid portion of glucuronide hydrolysis. Such competition may slow glucuronide hydrolysis and promote glucuronide excretion, including the glucuronides derived from aldosterone and cortisol.

  7. 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…

  8. 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.

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

    PubMed

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

    2013-12-02

    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.

  10. The Pulsating, Accreting White Dwarf in GW Lib after Outburst

    NASA Astrophysics Data System (ADS)

    Szkody, Paula

    The first known pulsating white dwarf in an accreting close binary system (GW Lib) underwent an outburst in April, 2007. We aim to follow the pulsation spectrum as the white dwarf cools back to to its quiescent temperature from its heating due to the outburst which should take about 3 years. As it cools, it should re-enter the instability strip and we can witness changes in the driving mechanism and detect modes that are excited by the temperature changes. The higher pulse amplitude in UV vs optical and the available time-tag mode makes GALEX the instrument of choice. The data in 2008 will be combined with our DOT time in May, June 2007 to provide coverage of the largest cooling that takes place in the year following outburst. Since the few known systems only outburst every 20-30 yrs, this is the first opportunity to accomplish a study of this type."

  11. 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.

  12. 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.

  13. 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.

  14. An Evaluation of Femtosecond/nanosecond Laser Induced Breakdown Spectroscopy (LIBS) for Measuring Total Particulate Emissions

    DTIC Science & Technology

    2009-05-07

    LIBS technique. Single-pulse ns-LIBS and dual-pulse fs/ns LIBS were then used to obtain calibration curves for: (1) carbon dioxide, (2) oxalic acid , and...solid carbon was in the form of 30-nm polystyrene (C8H8) and oxalic acid (COOH)2 particles. As noted in Figure 3.5, the intensities of the carbon...density oxalic acid (1.9 g/cm3) particles, has a larger slope than that for the polystyrene particles with a density of 1.0 g/cm3. The issue

  15. Clearing obstructed feeding tubes.

    PubMed

    Marcuard, S P; Stegall, K L; Trogdon, S

    1989-01-01

    This is a report of an in vitro study evaluating the ability of six solutions to dissolve clotted enteral feeding, which can cause feeding tube occlusion. The following clotted enteral feeding products were tested: Ensure Plus, Ensure Plus with added protein (Promod 20 g/liter), Osmolite, Enrich, and Pulmocare. Clot dissolution was then tested by adding Adolf's Meat Tenderizer, Viokase, Sprite, Pepsi, Coke, or Mountain Dew. Distilled water served as control. Dissolution score for each mixture was assessed blindly. Best dissolution was observed with Viokase in pH 7.9 solution (p less than 0.01). Similar results were obtained when feeding tube patency was restored in eight in vitro occluded feeding tubes (Dobbhoff, French size 8) by using first Pepsi (two/eight successful) and then Viokase in pH 7.9 (six/six successful). We also report our experience in the first 10 patients with occluded feeding tubes using this Viokase solution injected through a Drum catheter into the feeding tube. In seven patients, this method proved to be successful, and the reasons for failure in three patients include a knotted tube, impacted tablet powder, and a formula clot fo 24 hr duration and 45 cm in length.

  16. 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

  17. 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…

  18. [An automatic peak detection method for LIBS spectrum based on continuous wavelet transform].

    PubMed

    Chen, Peng-Fei; Tian, Di; Qiao, Shu-Jun; Yang, Guang

    2014-07-01

    Spectrum peak detection in the laser-induced breakdown spectroscopy (LIBS) is an essential step, but the presence of background and noise seriously disturb the accuracy of peak position. The present paper proposed a method applied to automatic peak detection for LIBS spectrum in order to enhance the ability of overlapping peaks searching and adaptivity. We introduced the ridge peak detection method based on continuous wavelet transform to LIBS, and discussed the choice of the mother wavelet and optimized the scale factor and the shift factor. This method also improved the ridge peak detection method with a correcting ridge method. The experimental results show that compared with other peak detection methods (the direct comparison method, derivative method and ridge peak search method), our method had a significant advantage on the ability to distinguish overlapping peaks and the precision of peak detection, and could be be applied to data processing in LIBS.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. LIBS: a potential tool for industrial/agricultural waste water analysis

    NASA Astrophysics Data System (ADS)

    Karpate, Tanvi; K. M., Muhammed Shameem; Nayak, Rajesh; V. K., Unnikrishnan; Santhosh, C.

    2016-04-01

    Laser Induced Breakdown Spectroscopy (LIBS) is a multi-elemental analysis technique with various advantages and has the ability to detect any element in real time. This technique holds a potential for environmental monitoring and various such analysis has been done in soil, glass, paint, water, plastic etc confirms the robustness of this technique for such applications. Compared to the currently available water quality monitoring methods and techniques, LIBS has several advantages, viz. no need for sample preparation, fast and easy operation, and chemical free during the process. In LIBS, powerful pulsed laser generates plasma which is then analyzed to get quantitative and qualitative details of the elements present in the sample. Another main advantage of LIBS technique is that it can perform in standoff mode for real time analysis. Water samples from industries and agricultural strata tend to have a lot of pollutants making it harmful for consumption. The emphasis of this project is to determine such harmful pollutants present in trace amounts in industrial and agricultural wastewater. When high intensity laser is made incident on the sample, a plasma is generated which gives a multielemental emission spectra. LIBS analysis has shown outstanding success for solids samples. For liquid samples, the analysis is challenging as the liquid sample has the chances of splashing due to the high energy of laser and thus making it difficult to generate plasma. This project also deals with determining the most efficient method for testing of water sample for qualitative as well as quantitative analysis using LIBS.

  6. Rapid detection of soils contaminated with heavy metals and oils by laser induced breakdown spectroscopy (LIBS).

    PubMed

    Kim, Gibaek; Kwak, Jihyun; Kim, Ki-Rak; Lee, Heesung; Kim, Kyoung-Woong; Yang, Hyeon; Park, Kihong

    2013-12-15

    A laser induced breakdown spectroscopy (LIBS) coupled with the chemometric method was applied to rapidly discriminate between soils contaminated with heavy metals or oils and clean soils. The effects of the water contents and grain sizes of soil samples on LIBS emissions were also investigated. The LIBS emission lines decreased by 59-75% when the water content increased from 1.2% to 7.8%, and soil samples with a grain size of 75 μm displayed higher LIBS emission lines with lower relative standard deviations than those with a 2mm grain size. The water content was found to have a more pronounced effect on the LIBS emission lines than the grain size. Pelletizing and sieving were conducted for all samples collected from abandoned mining areas and military camp to have similar water contents and grain sizes before being analyzed by the LIBS with the chemometric analysis. The data show that three types of soil samples were clearly discerned by using the first three principal components from the spectral data of soil samples. A blind test was conducted with a 100% correction rate for soil samples contaminated with heavy metals and oil residues.

  7. Field demonstrations of a direct push FO-LIBS metal sensor.

    PubMed

    Mosier-Boss, P A; Lieberman, S H; Theriault, G A

    2002-09-15

    A direct push, FO-LIBS sensor probe for real-time, in-situ measurement of metals in soils has been built and its capabilities demonstrated at three sites. The response of the FO-LIBS sensor is affected by the soil matrix conditions of grain size, composition, and water content. For each site, uncontaminated soil was collected and spiked with known quantities of the metal under investigation. These calibration standards were used to generate a site-specific calibration curve, which compensates for variations in soil matrix conditions of grain size, composition, porosity, etc. To compensate for moisture content, extra laser pulses are used to volatilize the water, higher power densities and/or shortened acquisition delay times are used. The LIBS experiment inherently exhibits poor precision since it is a point measurement. When multiple spectra are taken of a single, homogenized soil sample, there is a significant amount of variability in the peak intensities. There is no internal standard available to correct for this variability. In this communication, it is shown that normalizing the peak areas under the spectral curves to one effectively corrects for variation due to differences in the plasma volume. Because the LIBS technique is essentially a point measurement the FO-LIBS sensor is used as a semiquantitative field screening tool and not as a quantitative analytical method. In the field demonstrations reported in this communication, remarkably good agreement between the in-situ FO-LIBS results and ICP lab results were obtained.

  8. 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.

  9. Feeding Tubes

    MedlinePlus

    ... Feeding Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids ... Feeding Tubes Health Information Sheet Q & A with Experts Patient Stories Social Security Disability Application Process For Kids ...

  10. libRoadRunner: a high performance SBML simulation and analysis library

    PubMed Central

    Somogyi, Endre T.; Bouteiller, Jean-Marie; Glazier, James A.; König, Matthias; Medley, J. Kyle; Swat, Maciej H.; Sauro, Herbert M.

    2015-01-01

    Motivation: This article presents libRoadRunner, an extensible, high-performance, cross-platform, open-source software library for the simulation and analysis of models expressed using Systems Biology Markup Language (SBML). SBML is the most widely used standard for representing dynamic networks, especially biochemical networks. libRoadRunner is fast enough to support large-scale problems such as tissue models, studies that require large numbers of repeated runs and interactive simulations. Results: libRoadRunner is a self-contained library, able to run both as a component inside other tools via its C++ and C bindings, and interactively through its Python interface. Its Python Application Programming Interface (API) is similar to the APIs of MATLAB (www.mathworks.com) and SciPy (http://www.scipy.org/), making it fast and easy to learn. libRoadRunner uses a custom Just-In-Time (JIT) compiler built on the widely used LLVM JIT compiler framework. It compiles SBML-specified models directly into native machine code for a variety of processors, making it appropriate for solving extremely large models or repeated runs. libRoadRunner is flexible, supporting the bulk of the SBML specification (except for delay and non-linear algebraic equations) including several SBML extensions (composition and distributions). It offers multiple deterministic and stochastic integrators, as well as tools for steady-state analysis, stability analysis and structural analysis of the stoichiometric matrix. Availability and implementation: libRoadRunner binary distributions are available for Mac OS X, Linux and Windows. The library is licensed under Apache License Version 2.0. libRoadRunner is also available for ARM-based computers such as the Raspberry Pi. http://www.libroadrunner.org provides online documentation, full build instructions, binaries and a git source repository. Contacts: hsauro@u.washington.edu or somogyie@indiana.edu Supplementary information: Supplementary data are available

  11. Effect of feed presentation on feeding patterns of dairy calves.

    PubMed

    Miller-Cushon, E K; Bergeron, R; Leslie, K E; Mason, G J; DeVries, T J

    2013-01-01

    The objectives of this study were to determine the effect of feed presentation on meal frequency and duration, as well as diurnal feeding patterns of dairy calves, and to assess any longer-term differences in feeding patterns resulting from previous experience. Twenty Holstein bull calves were exposed from wk 1 to 8 of life to 1 of 2 feed presentation treatments: concentrate and chopped grass hay (<2.5 cm) offered at a ratio of 7:3 as a mixture (MIX), or as separate components (COM). Feed was provided ad libitum. Calves received 8L/d of milk replacer (1.2 kg of dry matter), with the amount progressively reduced after 5 wk to facilitate weaning by the end of wk 7. At the beginning of wk 9, all calves received the MIX diet and remained on trial for an additional 3 wk. Feeding behavior was recorded from video for 4d during wk 6, 8, 9, and 11. In wk 6, calves fed MIX spent more time feeding than calves fed COM (56.7 vs. 46.8 min/d). In wk 8, calves fed MIX spent more time feeding (174.0 vs. 139.1 min/d) and had a lower rate of intake (11.5 vs. 14.7 g/min) compared with calves fed COM. Meal frequency was similar between treatments (12.2 meals/d). Diurnal feeding patterns in wk 8 were also affected by feed presentation, with calves fed MIX spending less time feeding at time of feed delivery and more time feeding throughout the rest of the daylight hours than calves fed COM. Diurnal feeding patterns of hay and concentrate in wk 8 differed for calves fed COM, with more time spent consuming hay at time of feed delivery and less time spent consuming hay throughout the rest of the day. Once calves previously fed COM were transitioned to the MIX diet in wk 9, meal frequency, meal duration, and diurnal feeding patterns were similar between treatments: both treatments spent similar amounts of time feeding (173.9 min/d) and had similar peaks in feeding activity at time of feed delivery, sunrise, and sunset. Provision of hay and concentrate to young calves as a mixed ration

  12. Monitoring of toxic elements present in sludge of industrial waste using CF-LIBS.

    PubMed

    Kumar, Rohit; Rai, Awadhesh K; Alamelu, Devanathan; Aggarwal, Suresh K

    2013-01-01

    Industrial waste is one of the main causes of environmental pollution. Laser-induced breakdown spectroscopy (LIBS) was applied to detect the toxic metals in the sludge of industrial waste water. Sludge on filter paper was obtained after filtering the collected waste water samples from different sections of a water treatment plant situated in an industrial area of Kanpur City. The LIBS spectra of the sludge samples were recorded in the spectral range of 200 to 500 nm by focusing the laser light on sludge. Calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique was used for the quantitative measurement of toxic elements such as Cr and Pb present in the sample. We also used the traditional calibration curve approach to quantify these elements. The results obtained from CF-LIBS are in good agreement with the results from the calibration curve approach. Thus, our results demonstrate that CF-LIBS is an appropriate technique for quantitative analysis where reference/standard samples are not available to make the calibration curve. The results of the present experiment are alarming to the people living nearby areas of industrial activities, as the concentrations of toxic elements are quite high compared to the admissible limits of these substances.

  13. 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.

  14. Following the Pulsations of GW Lib and V455 and after Superoutburst

    NASA Astrophysics Data System (ADS)

    Szkody, Paula

    Two cataclysmic variables containing pulsating white dwarfs underwent outbursts in 2007 (GW Lib and V455 And). As we know outbursts heat the white dwarfs by more than 10,000K and they gradually cool to their quiescent temperatures over the course of about 3 years, these two objects present the first unique opportunity to follow the pulsation spectrum of a white dwarf as it cools on much more rapid timescales than evolutionary ones for single white dwarfs. As these 2 objects cool, they should re-enter their instability strips and we can witness changes in the driving mechanism and detect modes that are excited by the T changes. Our 2008 ground-based data on GW Lib has shown a new pulsation at a longer period than at quiescence. The data in 2009 will be combined with our time for GW Lib in Cycle 4 and our DOT time in 2007 to follow the long term cooling of GW Lib and obtain similar information on V455 And. The higher pulse amplitude in UV vs optical and the time-tag mode means that GALEX can provide optimum data over the optical. Data on both systems will provide an important contrast in how the white dwarfs react to an outburst, as GW Lib at quiescence has a hot white dwarf far outside the normal instability strip for non-accreting white dwarfs, while V455 And is cool and inside this strip.

  15. 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)

  16. libRASCH--a programming framework for transparent access to physiological signals.

    PubMed

    Schneider, R; Bauer, A; Barthel, P; Schmidt, G

    2004-01-01

    For the analysis of physiological signals, such as ECG's, continuous blood pressure recordings etc., access to the raw signal data as well as to processed data is mandatory. Up to now, there is no computer program which allows access to raw and processed data independently from the file formats used. Thus, programs have to be adapted to each new file format. The aim of the programming library 'libRASCH', is to provide an interface which allows the access to physiological signals in a consistent way. libRASCH is written in C and runs under Linux and Windows. The source code of libRASCH is published under the GNU LGPL. A plugin mechanism for extension of the library was implemented. Support for some widely used data formats (e.g. European Data Format) is already available. To support a new file-format, only the corresponding plugin has to be written. Moreover all programs using this library, can handle the new format without further adjustments. For other programming languages than C (e.g. Perl, Python), interfaces are available. On the libRASCH website (http://www.librasch.org), the source code of libRASCH and further information's are available.

  17. Inverse Calibration Free fs-LIBS of Copper-Based Alloys

    NASA Astrophysics Data System (ADS)

    Smaldone, Antonella; De Bonis, Angela; Galasso, Agostino; Guarnaccio, Ambra; Santagata, Antonio; Teghil, Roberto

    2016-09-01

    In this work the analysis by Laser Induced Breakdown Spectroscopy (LIBS) technique of copper-based alloys having different composition and performed with fs laser pulses is presented. A Nd:Glass laser (Twinkle Light Conversion, λ = 527 nm at 250 fs) and a set of bronze and brass certified standards were used. The inverse Calibration-Free method (inverse CF-LIBS) was applied for estimating the temperature of the fs laser induced plasma in order to achieve quantitative elemental analysis of such materials. This approach strengthens the hypothesis that, through the assessment of the plasma temperature occurring in fs-LIBS, straightforward and reliable analytical data can be provided. With this aim the capability of the here adopted inverse CF-LIBS method, which is based on the fulfilment of the Local Thermodynamic Equilibrium (LTE) condition, for an indirect determination of the species excitation temperature, is shown. It is reported that the estimated temperatures occurring during the process provide a good figure of merit between the certified and the experimentally determined composition of the bronze and brass materials, here employed, although further correction procedure, like the use of calibration curves, can be demanded. The reported results demonstrate that the inverse CF-LIBS method can be applied when fs laser pulses are used even though the plasma properties could be affected by the matrix effects restricting its full employment to unknown samples provided that a certified standard having similar composition is available.

  18. The mutual effect of metal sample and turboflame in LIBS signal enhancement

    NASA Astrophysics Data System (ADS)

    Ghezelbash, M.; Mousavi, S. J.; Majd, A. E.; Darbani, S. M. R.; Saghafifar, H.; Maleki, A.

    2016-08-01

    The main aim of the present study is to evaluate the mutual effect of copper sample and turboflame in laser induced breakdown spectroscopy (LIBS) signal enhancement. The use of copper sample leads to a signal enhancement in CN ( B 2Σ+- X 2Σ+) 384.2-388.4 nm molecular transition, N742nm, N744nm, N746nm (a triplet generated by the fine splitting of the 2 s 22 p 2(3 P)3 s-2 s 22 p 2(3 P)3 p transition) and Hα, 656.3 nm (as a flame inductor) atomic lines analysis. Additionally, increase in copper sample temperature with flame can enhance the Cu atomic line intensities (as copper sample inductors). Moreover, in this paper, the comparison between turboflame and alcohol flame on LIBS analysis was studied. LIBS signal intensity variation in a turboflame and turboflame coupled with copper sample at different laser pulse energies indicated that the low laser pulse energy could be compensated by using a copper sample that is coupled with turboflame and improved LIBS signal enhancement. For flames analysis, the use of metal sample in LIBS method is demonstrated to be costeffective, compact, and capable of signal enhancement.

  19. 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

  20. Feasibility Study for Monitoring Actinide Elements in Process Materials Using FO-LIBS at Advanced spent fuel Conditioning Process Facility

    SciTech Connect

    Han, Bo-Young; Choi, Daewoong; Park, Se Hwan; Kim, Ho-Dong; Dae, Dongsun; Whitehouse, Andrew I.

    2015-07-01

    Korea Atomic Energy Research Institute (KAERI) have been developing the design and deployment methodology of Laser- Induced Breakdown Spectroscopy (LIBS) instrument for safeguards application within the argon hot cell environment at Advanced spent fuel Conditioning Process Facility (ACPF), where ACPF is a facility being refurbished for the laboratory-scaled demonstration of advanced spent fuel conditioning process. LIBS is an analysis technology used to measure the emission spectra of excited elements in the local plasma of a target material induced by a laser. The spectra measured by LIBS are analyzed to verify the quality and quantity of the specific element in the target matrix. Recently LIBS has been recognized as a promising technology for safeguards purposes in terms of several advantages including a simple sample preparation and in-situ analysis capability. In particular, a feasibility study of LIBS to remotely monitor the nuclear material in a high radiation environment has been carried out for supporting the IAEA safeguards implementation. Fiber-Optic LIBS (FO-LIBS) deployment was proposed by Applied Photonics Ltd because the use of fiber optics had benefited applications of LIBS by delivering the laser energy to the target and by collecting the plasma light. The design of FO-LIBS instrument for the measurement of actinides in the spent fuel and high temperature molten salt at ACPF had been developed in cooperation with Applied Photonics Ltd. FO-LIBS has some advantages as followings: the detectable plasma light wavelength range is not limited by the optical properties of the thick lead-glass shield window and the potential risk of laser damage to the lead-glass shield window is not considered. The remote LIBS instrument had been installed at ACPF and then the feasibility study for monitoring actinide elements such as uranium, plutonium, and curium in process materials has been carried out. (authors)

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

    DOE PAGES

    Anderson, Aaron S.; Mukundan, Harshini; Mcinroy, Rhonda E.; ...

    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

  2. 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.

  3. 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.

  4. Analysis of environmental lead contamination: comparison of LIBS field and laboratory instruments

    NASA Astrophysics Data System (ADS)

    Wainner, R. T.; Harmon, R. S.; Miziolek, A. W.; McNesby, K. L.; French, P. D.

    2001-06-01

    The Army Research Office of the Army Research Laboratory recently sponsored the development of a commercial laser-induced breakdown spectroscopy (LIBS) chemical sensor that is sufficiently compact and robust for use in the field. This portable unit was developed primarily for the rapid, non-destructive detection of lead (Pb) in soils and in paint. In order to better characterize the portable system, a comparative study was undertaken in which the performance of the portable system was compared with a laboratory LIBS system at the Army Research Laboratory that employs a much more sophisticated laser and detector. The particular focus of this study was to determine the effects on the performance of the field sensor's lower spectral resolution, lack of detector gating, and the multiple laser pulsing that occurs when using a passively Q-switched laser. Surprisingly, both the laboratory and portable LIBS systems exhibited similar performance with regards to detection of Pb in both soils and in paint over the 0.05-1% concentration levels. This implies that for samples similar to those studied here, high-temporal resolution time gating of the detector is not necessary for quantitative analysis by LIBS. It was also observed that the multiple pulsing of the laser did not have a significant positive or negative effect on the measurement of Pb concentrations. The alternative of using other Pb lines besides the strong 406-nm line was also investigated. No other Pb line was superior in strength to the 406-nm line for the latex paint and the type of soils used in the study, although the emission line at 220 nm in the UV portion of the spectrum holds potential for avoiding elemental interferences. These results are very encouraging for the development of lightweight, portable LIBS sensors that use less expensive and less sophisticated laser and detector components. The portable LIBS system was also field tested successfully at sites of documented Pb contamination on military

  5. Characterization and forensic analysis of soil samples using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Jantzi, Sarah C; Almirall, José R

    2011-07-01

    A method for the quantitative elemental analysis of surface soil samples using laser-induced breakdown spectroscopy (LIBS) was developed and applied to the analysis of bulk soil samples for discrimination between specimens. The use of a 266 nm laser for LIBS analysis is reported for the first time in forensic soil analysis. Optimization of the LIBS method is discussed, and the results compared favorably to a laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method previously developed. Precision for both methods was <10% for most elements. LIBS limits of detection were <33 ppm and bias <40% for most elements. In a proof of principle study, the LIBS method successfully discriminated samples from two different sites in Dade County, FL. Analysis of variance, Tukey's post hoc test and Student's t test resulted in 100% discrimination with no type I or type II errors. Principal components analysis (PCA) resulted in clear groupings of the two sites. A correct classification rate of 99.4% was obtained with linear discriminant analysis using leave-one-out validation. Similar results were obtained when the same samples were analyzed by LA-ICP-MS, showing that LIBS can provide similar information to LA-ICP-MS. In a forensic sampling/spatial heterogeneity study, the variation between sites, between sub-plots, between samples and within samples was examined on three similar Dade sites. The closer the sampling locations, the closer the grouping on a PCA plot and the higher the misclassification rate. These results underscore the importance of careful sampling for geographic site characterization.

  6. 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.

  7. 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.

  8. 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.

  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.

  10. Geochemical analysis of layered outcrops using laser-induced breakdown spectroscopy (LIBS) - Implications for Mars exploration

    NASA Astrophysics Data System (ADS)

    Sobron, P.; Lefebvre, C.; Leveille, R. J.; Koujelev, A.; Haltigin, T.; Hongwei, D.; Wang, A.; Cabrol, N. A.; Zacny, K.; Craft, J.

    2012-12-01

    The chemistry and the stratigraphy of sedimentary, evaporative, and other types of deposits are indicators of their depositional environment and climate, and the evolution of these over time. Over the past eight years, the Mars Exploration Rovers (MER) have investigated several outcrops at Meridiani Planum and Gusev Crater. Compared to the MER, the capabilities of Curiosity to investigate outcrops and other deposits are enhanced because the rover incorporates a stand-off laser-induced breakdown spectroscopy (LIBS) instrument within the ChemCam suite. ChemCam's LIBS instrument has the capability to obtain chemical information from a large variety of targets at various distances, up to 7 m, including targets at a distance within stratigraphic layers non-accessible to other payload elements. In this work we demonstrate that semi-quantitative chemical stratigraphy can be very rapidly obtained by performing LIBS measurements on visually distinct layers within an outcrop at a terrestrial Mars analogue: the Atacama Desert, Chile. Such semi-quantitative chemical stratigraphy provides very valuable information on the distribution of elements within the analyzed layers, which can be used for tactical mission planning purposes. We performed laboratory laser-induced breakdown spectroscopy (LIBS) and laser Raman spectroscopy measurement on field samples from a layered outcrop from the Atacama Desert, Chile. This layered outcrop is a good terrestrial morphological analogue for similar formations that will likely be investigated by the Mars Science Laboratory on Gale crater. Our results demonstrate that LIBS can generate semi-quantitative chemical profiles in less than 1 min using automated data processing tools, and therefore the LIBS instrument can become an invaluable tactical tool on MSL for rapid geochemical survey of layered outcrops. The derived chemical profile at the terrestrial analogue is consistent with the range of minerals identified by Raman spectroscopy. In the

  11. 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…

  12. 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…

  13. On-Premises Library versus Google-Like Information Gateway Usage Patterns: A LibQUAL+[R] Study

    ERIC Educational Resources Information Center

    Thompson, Bruce; Kyrillidou, Martha; Cook, Colleen

    2007-01-01

    Using LibQUAL+[R] data provided by 295,355 of the participants who completed the LibQUAL+[R] survey in 2003, 2004, and 2005, the present study was conducted to address three research questions. First, what differences, if any, have occurred across time in the use by (a) undergraduates, (b) graduate students/postgraduates, and (c) faculty of…

  14. Commutating Feed Assembly.

    DTIC Science & Technology

    1979-12-01

    AD-AOBS 567 ITT GILFILLAN VAN NUYS CA F/6 17/9 CONF4UTATING FEED ASSEMBLY. 1W DEC 79 R WOL.FSON F19628-79-C-OOSS UNCLASSIFIED RADC -TR79303 NI. 1i.ll...INTRODUCTION 9 2 COMMUTATING FEED ASSEMBLY REQUIREMENTS 10 . 3 TECHNICAL PROBLEMS 11 1: 3.1 System Design 12 3.1.1 Radius of Circular Array 12 3.1.2 Design...Support Structure 16 3.3 Annular Rotary Coupler 16 3.4 Stripline Feed Network 17 w V.3.4.1 Range of Coupling Values vs. Percent Power into Load 17 3.4.2

  15. 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.

  16. 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.

  17. Orientifolded locally AdS3 geometries

    NASA Astrophysics Data System (ADS)

    Loran, F.; Sheikh-Jabbari, M. M.

    2011-01-01

    Continuing the analysis of [Loran F and Sheikh-Jabbari M M 2010 Phys. Lett. B 693 184-7], we classify all locally AdS3 stationary axi-symmetric unorientable solutions to AdS3 Einstein gravity and show that they are obtained by applying certain orientifold projection on AdS3, BTZ or AdS3 self-dual orbifold, respectively, O-AdS3, O-BTZ and O-SDO geometries. Depending on the orientifold fixed surface, the O-surface, which is either a space-like 2D plane or a cylinder, or a light-like 2D plane or a cylinder, one can distinguish four distinct cases. For the space-like orientifold plane or cylinder cases, these geometries solve AdS3 Einstein equations and are hence locally AdS3 everywhere except at the O-surface, where there is a delta-function source. For the light-like cases, the geometry is a solution to Einstein equations even at the O-surface. We discuss the causal structure for static, extremal and general rotating O-BTZ and O-SDO cases as well as the geodesic motion on these geometries. We also discuss orientifolding Poincaré patch AdS3 and AdS2 geometries as a way to geodesic completion of these spaces and comment on the 2D CFT dual to the O-geometries.

  18. 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.

  19. Engineering superconductors with ab initio methods: the example of LiB

    NASA Astrophysics Data System (ADS)

    Curtarolo, Stefano

    2007-03-01

    The identification of novel crystal structures is a fundamental step for predicting new stable compounds in alloys. While performing ab initio data mining of intermetallic compounds [1], we discover a new family of layered metal borides [2], of which MgB2 is one particular element (the new phases are called Metal Sandwich (MS)). Thermodynamic stability and electronic properties of these MS phases are investigated in details, leading to the prediction of a hypothetical novel superconductor MS-LiB [2,3]. Calculations show that the MS phases in the Li-B system exhibit electronic features similar to those of MgB2 [2,3] and CaC6 [4]. Although the predicted critical temperature of LiB is lower than that of MgB2 (references [4] and [5] for MS2-LiB and MS1-LiB, respectively), the peculiarities of MS-LiB in terms of electronic structure, layer arrangements and doping capabilities allow a lot of freedom in the search for higher Tc systems [5]. We acknowledge the San Diego Supercomputer Center for computational resources. [1] S. Curtarolo et al., Phys. Rev. Lett. 91, 135503 (2003). [2] A.N. Kolmogorov, S. Curtarolo, Phys. Rev. B 73, 180501(R) (2006). [3] A.N. Kolmogorov, S. Curtarolo, in press, Phys. Rev B 74 (2006), condmat/0607654. [4] A.Y. Liu, I.I. Mazin, cond-mat/0610057. [5] M. Calandra, A.N. Kolmogorov, S. Curtarolo, submitted (2006).

  20. Involving Faculty in BI-LIB 111: Information Literacy at Ulster County Community College

    ERIC Educational Resources Information Center

    Walsh, Robin

    2003-01-01

    Since 1995, faculty at Ulster County Community College (now SUNY Ulster) have been teaching LIB 111: Information Literacy. As a result of an information literacy initiative that began in 1992, the reference librarians and faculty at SUNY Ulster developed an award-winning information literacy course. Teaching faculty are trained to teach the…

  1. 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

  2. An exploratory study of the potential of LIBS for visualizing gunshot residue patterns.

    PubMed

    López-López, María; Alvarez-Llamas, César; Pisonero, Jorge; García-Ruiz, Carmen; Bordel, Nerea

    2017-04-01

    The study of gunshot residue (GSR) patterns can assist in the reconstruction of shooting incidences. Currently, there is a real need of methods capable of furnishing simultaneous elemental analysis with higher specificity for the GSR pattern visualization. Laser-Induced Breakdown Spectroscopy (LIBS) provides a multi-elemental analysis of the sample, requiring very small amounts of material and no sample preparation. Due to these advantages, this study aims at exploring the potential of LIBS imaging for the visualization of GSR patterns. After the spectral characterization of individual GSR particles, the distribution of Pb, Sb and Ba over clothing targets, shot from different distances, were measured in laser raster mode. In particular, an array of spots evenly spaced at 800μm, using a stage displacement velocity of 4mm/s and a laser frequency of 5Hz was employed (e.g. an area of 130×165mm(2) was measured in less than 3h). A LIBS set-up based on the simultaneous use of two spectrographs with iCCD cameras and a motorized stage was used. This set-up allows obtaining information from two different wavelength regions (258-289 and 446-463nm) from the same laser induced plasma, enabling the simultaneous detection of the three characteristic elements (Pb, Sb, and Ba) of GSR particles from conventional ammunitions. The ability to visualize the 2D distribution GSR pattern by LIBS may have an important application in the forensic field, especially for the ballistics area.

  3. 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…

  4. Using Localized Survey Items to Augment Standardized Benchmarking Measures: A LibQUAL+[TM] Study

    ERIC Educational Resources Information Center

    Thompson, Bruce; Cook, Colleen; Kyrillidou, Martha

    2006-01-01

    The LibQUAL+[TM] protocol solicits open-ended comments from users with regard to library service quality, gathers data on 22 core items, and, at the option of individual libraries, also garners ratings on five items drawn from a pool of more than 100 choices selected by libraries. In this article, the relationship of scores on these locally…

  5. Faculty Perception of Information Control Using LibQUAL+[TM] Indicators

    ERIC Educational Resources Information Center

    Kayongo, Jessica; Jones, Sherri

    2008-01-01

    The LibQUAL+[TM] survey was used in 2006 to assess library service quality at the University of Notre Dame. While results showed that the Libraries were meeting users' expectations for service in most areas, a closer examination of the data revealed dissatisfaction from a subgroup of users in one particular dimension of library services. This…

  6. 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…

  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.

  8. 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…

  9. Enteral feedings.

    PubMed

    Chernoff, R

    1980-01-01

    The benefits, equipment used, commercially available sources, and the indications and techniques for administration of enteral nutrients are reviewed. In many malabsorption states, enteral feeding is preferable and parenteral nutrients are seldom indicated. Transitional enteral nutrient support usually is indicated after parenteral nutrient therapy. Enteral tube-feeding formulas should be matched to the patient's needs; formulas using blenderized natural foods or intact isolated nutrients are appropriate for patients with intact gastrointestinal tracts. Patients should be monitored for glucosuria and hyperglycemia, bloating, nausea, dehydration, and renal, hepatic and hematologic status. Formula dilution, and a reduced flow rate or use of continuous-drip feeding, will reduce the incidence of osmotic diarrhea. The effectiveness, low cost and low potential for serious complications make enteral feeding preferable to parenteral nutrient therapy for many patients.

  10. Forensic elemental analysis of materials by laser induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Almirall, Jose R.; Umpierrez, Sayuri; Castro, Waleska; Gornushkin, Igor; Winefordner, James

    2005-05-01

    Materials analysis and characterization can provide important information as evidence in legal proceedings. Although the utility of trace elemental analyses for comparisons of glass, paint chips, bullet lead and metal fragments has been shown to offer a high degree of discrimination between different sources of these materials, the instrumentation required for the generation of good analytical data in forensic comparisons can be beyond the reach of many forensic laboratories. Scanning Electron Microscopy with an Energy Dispersive Spectrometer (SEM-EDS), X-Ray Fluorescence (XRF), Laser Ablation Inductively Coupled Plasma Atomic Emission Spectroscopy (LA-ICP-AES) and, more recently, LA-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) have been used in forensic laboratories for elemental analysis determinations. A newly developed Laser Induced Breakdown Spectroscopy (LIBS) instrument (Foster and Freeman Ltd., Evesham, U.K.) has been evaluated as a tool for the forensic elemental analysis of glass and compared in performance to other elemental methods in order to determine the utility of comparing casework sized glass samples. Developments in the instrumental design of this LIBS system, which is specifically designed to address the analytical requirements of the forensic laboratory, are presented. The utility of the LIBS system for the analysis of glass, paint, metals, gun shot residue and other matrices are also presented. The power of the LIBS-based elemental analysis to discriminate between different glass samples is also compared to the discrimination power of SEM-EDS, XRF and LA-ICP-MS. The relatively low cost (expected to be $ 60,000.), ease of operation and almost non-destructive nature of the LIBS analysis makes the technique a viable forensic elemental analysis tool.

  11. [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.

  12. Breast-Feeding Twins: Making Feedings Manageable

    MedlinePlus

    ... breast-feed more than one baby? Here's help breast-feeding twins or other multiples, from getting positioned and ensuring an adequate milk supply to combining breast-feeding and formula-feeding. By Mayo Clinic Staff If ...

  13. Warped AdS3 black holes

    NASA Astrophysics Data System (ADS)

    Anninos, Dionysios; Li, Wei; Padi, Megha; Song, Wei; Strominger, Andrew

    2009-03-01

    Three dimensional topologically massive gravity (TMG) with a negative cosmological constant -l-2 and positive Newton constant G admits an AdS3 vacuum solution for any value of the graviton mass μ. These are all known to be perturbatively unstable except at the recently explored chiral point μl = 1. However we show herein that for every value of μl ≠ 3 there are two other (potentially stable) vacuum solutions given by SL(2,Bbb R) × U(1)-invariant warped AdS3 geometries, with a timelike or spacelike U(1) isometry. Critical behavior occurs at μl = 3, where the warping transitions from a stretching to a squashing, and there are a pair of warped solutions with a null U(1) isometry. For μl > 3, there are known warped black hole solutions which are asymptotic to warped AdS3. We show that these black holes are discrete quotients of warped AdS3 just as BTZ black holes are discrete quotients of ordinary AdS3. Moreover new solutions of this type, relevant to any theory with warped AdS3 solutions, are exhibited. Finally we note that the black hole thermodynamics is consistent with the hypothesis that, for μl > 3, the warped AdS3 ground state of TMG is holographically dual to a 2D boundary CFT with central charges c_R-formula and c_L-formula.

  14. Warped AdS3 black holes

    NASA Astrophysics Data System (ADS)

    Song, Wei; Anninos, Dionysios; Li, Wei; Padi, Megha; Strominger, Andrew

    2009-03-01

    Three dimensional topologically massive gravity (TMG) with a negative cosmological constant -ell-2 and positive Newton constant G admits an AdS3 vacuum solution for any value of the graviton mass μ. These are all known to be perturbatively unstable except at the recently explored chiral point μell = 1. However we show herein that for every value of μell ≠ 3 there are two other (potentially stable) vacuum solutions given by SL(2,Bbb R) × U(1)-invariant warped AdS3 geometries, with a timelike or spacelike U(1) isometry. Critical behavior occurs at μell = 3, where the warping transitions from a stretching to a squashing, and there are a pair of warped solutions with a null U(1) isometry. For μell > 3, there are known warped black hole solutions which are asymptotic to warped AdS3. We show that these black holes are discrete quotients of warped AdS3 just as BTZ black holes are discrete quotients of ordinary AdS3. Moreover new solutions of this type, relevant to any theory with warped AdS3 solutions, are exhibited. Finally we note that the black hole thermodynamics is consistent with the hypothesis that, for μell > 3, the warped AdS3 ground state of TMG is holographically dual to a 2D boundary CFT with central charges c_R-formula and c_L-formula.

  15. A Simple Device for Lens-to-Sample Distance Adjustment in Laser-Induced Breakdown Spectroscopy (LIBS).

    PubMed

    Cortez, Juliana; Farias Filho, Benedito B; Fontes, Laiane M; Pasquini, Celio; Raimundo, Ivo M; Pimentel, Maria Fernanda; de Souza Lins Borba, Flávia

    2017-01-01

    A simple device based on two commercial laser pointers is described to assist in the analysis of samples that present uneven surfaces and/or irregular shapes using laser-induced breakdown spectroscopy (LIBS). The device allows for easy positioning of the sample surface at a reproducible distance from the focusing lens that conveys the laser pulse to generate the micro-plasma in a LIBS system, with reproducibility better than ±0.2 mm. In this way, fluctuations in the fluence (J cm(-2)) are minimized and the LIBS analytical signals can be obtained with a better precision even when samples with irregular surfaces are probed.

  16. 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

  17. Remote Laser Induced Breakdown Spectroscopy (LIBS) of Martian Meteorites and Other Basaltic Samples

    NASA Astrophysics Data System (ADS)

    Clegg, S. M.; Thompson, J. R.; Wiens, R. C.; Barefield, J. E.; Vaniman, D. T.; Newsom, H. E.

    2005-12-01

    Laser Induced Breakdown Spectroscopy (LIBS) is a rapid and quantitative analytical tool for elemental analysis in terrestrial1 and Martian environments. LIBS is one of two instruments comprising the "ChemCam" package recently selected for the Mars Science Laboratory (MSL) Rover Mission scheduled to launch in 2009. LIBS will be the first active remote sensing instrument to fly on a NASA rover, designed to interrogate samples to a distance of 9 m. In preparation for the MSL mission, we are working to improve our ability to extract quantitative results under the Martian environment. We recently completed a study in which we extracted quantitative elemental concentrations and calculated the oxide concentrations from two Martian basaltic shergottite meteorites, Dar al Gani (DaG) 476 and Zagami. The current LIBS laboratory setup involves ablating some material from the sample surface with a focused Nd:YAG (1064nm) laser. The ablated material produces a supersonically expanding plasma of electronically excited atoms. A dispersive spectrometer and an ICCD camera are used to record the spectral signatures emitted from the electronically excited atoms. In our experimental set-up, samples were placed at a distance of 5.4 m from the instrument in a vacuum chamber filled with 7 Torr CO2 to simulate the Martian atmosphere. Terrestrial basalt standards were used to generate calibration curves for all of the major elements and some of the minor and trace species including Si, Fe, Mg, Ca, Ti, Al, and Na. First, two blind basalt standards were analyzed and their compositions were found to match the actual compositions within the uncertainty of the measurement, being correctly distinguished from other available basalt standards. Next, LIBS was used to distinguish between two different basaltic Martian meteorites. Using 14 analysis spots of ~400 μm diameter on DaG 476 and 9 analysis spots on Zagami, LIBS distinguished the olivine-phyric (DaG 476) from the basaltic (Zagami

  18. 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.

  19. Segmented strings in AdS 3

    NASA Astrophysics Data System (ADS)

    Callebaut, Nele; Gubser, Steven S.; Samberg, Andreas; Toldo, Chiara

    2015-11-01

    We study segmented strings in flat space and in AdS 3. In flat space, these well known classical motions describe strings which at any instant of time are piecewise linear. In AdS 3, the worldsheet is composed of faces each of which is a region bounded by null geodesics in an AdS 2 subspace of AdS 3. The time evolution can be described by specifying the null geodesic motion of kinks in the string at which two segments are joined. The outcome of collisions of kinks on the worldsheet can be worked out essentially using considerations of causality. We study several examples of closed segmented strings in AdS 3 and find an unexpected quasi-periodic behavior. We also work out a WKB analysis of quantum states of yo-yo strings in AdS 5 and find a logarithmic term reminiscent of the logarithmic twist of string states on the leading Regge trajectory.

  20. Spectroscopic analysis of works of art using a single LIBS and pulsed Raman setup.

    PubMed

    Osticioli, I; Mendes, N F C; Porcinai, S; Cagnini, A; Castellucci, E

    2009-06-01

    A nanosecond pulsed laser setup has been optimized to perform laser-induced breakdown spectroscopy (LIBS) and pulsed Raman spectroscopy measurements in the field of cultural heritage. Three different samples of artistic/architectural interest with different typologies have been analyzed. The results from the two techniques allowed the identification of the materials used in their manufacture or contaminating them, probably coming from atmospheric pollution and biological activity. No sampling and sample preparation was required before the measurements, and no visual or structural damage was observed. Depth profiling using LIBS was performed in one of the samples, providing elemental information along the different layers composing the object and covering its surface. The quality of the results and the rather short time needed for the measurements and for switching between techniques confirmed the instrument's capabilities and specificity for dealing with objects of artistic or historical interest.

  1. GH Lib: A multi-periodic Mira, not an eclipsing binary

    NASA Astrophysics Data System (ADS)

    Siviero, Alessandro; Munari, Ulisse; Righetti, Gian Luigi; Graziani, Mauro

    2016-09-01

    Over the period 2012-2016 we have obtained accurate V and R band photometry and 3400-8000 Ang spectroscopy which show the poorly studied variable GH Lib to be a multi-periodic Mira and not an Algol-type eclipsing binary. The main pulsation periods are 157 and 1180 days, with amplitudes of 3.5 and 1.0 mag, respectively. The spectral type change from M2III at maximum to M7III at minimum. The intensity of Halpha and Hbeta emission lines in GH Lib is much larger than in normal Miras, suggesting that the region of Balmer line formation is located at a larger radius (more external atmospheric layers) as if mixed with and not deeply below the region where absorption by TiO molecules occurs.

  2. 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)

  3. GammaLib: A New Framework for the Analysis of Astronomical Gamma-Ray Data

    NASA Astrophysics Data System (ADS)

    Knödlseder, J.

    2012-09-01

    With the advent of a new generation of telescopes (INTEGRAL, Fermi, H.E.S.S., MAGIC, VERITAS, MILAGRO) and the prospects of planned observatories such as CTA or HAWC, gamma-ray astronomy is becoming an integral part of modern astrophysical research. Analysing gamma-ray data is still a major challenge, and today relies on a large diversity of tools and software frameworks that were specifically developed for each instrument. With the goal of facilitating and unifying the analysis of gamma-ray data, we are currently developing an innovative data analysis toolbox, called the GammaLib, that enables gamma-ray data analysis in an instrument independent way. We will present the basic ideas that are behind the GammaLib, and describe its architecture and usage.

  4. 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

  5. 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…

  6. 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…

  7. Effect of milk feeding level on development of feeding behavior in dairy calves.

    PubMed

    Miller-Cushon, E K; Bergeron, R; Leslie, K E; DeVries, T J

    2013-01-01

    Evidence exists that early life experiences may influence development of characteristic feeding patterns in dairy cattle. The objective of this study was to determine the effect of milk feeding level on performance and development of feeding patterns in dairy calves. Twenty Holstein bull calves were assigned at birth to a milk replacer feeding level, fed via a teat: (1) ad libitum (ADL) or (2) restricted feeding at 5 L/d (0.75 kg of milk replacer) in 2 feedings/d (RES). All calves were offered concentrate ad libitum during the milk feeding stage. Calves were weaned gradually during wk 7 and then fed a pelleted diet ad libitum for 7 wk. Calves were weighed 2 times/wk. Feed and milk intakes were recorded daily. Feeding behavior was recorded from video for 5 d in each of wk 3, 6, 8, 11, and 14. Calves fed ADL consumed 2.6 times more milk, had greater weight gain (1.2 vs. 0.6 kg/d), and consumed less solid feed (45.2 vs. 98.0 g/d) during the milk feeding period than did calves fed RES. As expected, providing milk ADL resulted in more frequent meals (in wk 6, 7.1 vs. 2.0) and more evenly distributed diurnal patterns of feeding activity compared with the RES milk level. When considering all sucking bouts (milk feeding and nonnutritive sucking), no difference was observed between treatments in daily bout frequency or sucking time/bout. Postweaning, calves fed RES had initially greater rate of intake (24.9 vs. 17.8 g/min) and meal size (160.8 vs. 117.2 g/meal). Diurnal feeding patterns also differed in the first week after weaning, with ADL calves feeding less continuously at the time of feed delivery. Meal characteristics and diurnal patterns of feeding activity were similar between calves by the end of the trial. However, milk feeding level had a longer-term effect on variability in feeding behavior, with calves fed RES having greater day-to-day variability in feeding time and meal size. Variability of meal characteristics also decreased over time across treatments

  8. Analysis Si/Al ratio in zeolites type FAU by laser induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Contreras, W. A.; Cabanzo, R.; Mejía-Ospino, E.

    2011-01-01

    In this work, Laser Induced Breakdown Spectroscopy (LIBS) is used to determine the Si/Al ratio of Zeolite type Y. The catalytic activity of zeolite is strongly dependent of the Si/Al ratio. We have used Si lines in the spectral region between 245-265 nm to determine temperature of the plasma generated on pelletized sample of zeolite, and stoichiometry relation between Si and Al.

  9. ENDF/B-V, LIB-V, and the CSEWG benchmarks

    SciTech Connect

    Kidman, R.B.

    1981-08-01

    A 70-group library, LIB-V, generated with the NJOY processing code from ENDF/B-V, is tested on most of the Cross Section Evaluation Working Group (CSEWG) fast reactor benchmarks. Every experimental measurement reported in the benchmark specifications is compared to both diffusion theory and transport theory calculations. Several comparisons with prior benchmark calculations attempt to assess the effects of data and code improvements.

  10. 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.

  11. EggLib: processing, analysis and simulation tools for population genetics and genomics

    PubMed Central

    2012-01-01

    Background With the considerable growth of available nucleotide sequence data over the last decade, integrated and flexible analytical tools have become a necessity. In particular, in the field of population genetics, there is a strong need for automated and reliable procedures to conduct repeatable and rapid polymorphism analyses, coalescent simulations, data manipulation and estimation of demographic parameters under a variety of scenarios. Results In this context, we present EggLib (Evolutionary Genetics and Genomics Library), a flexible and powerful C++/Python software package providing efficient and easy to use computational tools for sequence data management and extensive population genetic analyses on nucleotide sequence data. EggLib is a multifaceted project involving several integrated modules: an underlying computationally efficient C++ library (which can be used independently in pure C++ applications); two C++ programs; a Python package providing, among other features, a high level Python interface to the C++ library; and the egglib script which provides direct access to pre-programmed Python applications. Conclusions EggLib has been designed aiming to be both efficient and easy to use. A wide array of methods are implemented, including file format conversion, sequence alignment edition, coalescent simulations, neutrality tests and estimation of demographic parameters by Approximate Bayesian Computation (ABC). Classes implementing different demographic scenarios for ABC analyses can easily be developed by the user and included to the package. EggLib source code is distributed freely under the GNU General Public License (GPL) from its website http://egglib.sourceforge.net/ where a full documentation and a manual can also be found and downloaded. PMID:22494792

  12. GPCR-GRAPA-LIB--a refined library of hidden Markov Models for annotating GPCRs.

    PubMed

    Shigeta, Ron; Cline, Melissa; Liu, Guoying; Siani-Rose, Michael A

    2003-03-22

    GPCR-GRAPA-LIB is a library of HMMs describing G protein coupled receptor families. These families are initially defined by class of receptor ligand, with divergent families divided into subfamilies using phylogenic analysis and knowledge of GPCR function. Protein sequences are applied to the models with the GRAPA curve-based selection criteria. RefSeq sequences for Homo sapiens, Drosophila melanogaster, and Caenorhabditis elegans have been annotated using this approach.

  13. 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.

  14. Rocks analysis at stand off distance by LIBS in Martian conditions

    SciTech Connect

    Wiens, R. C.; Cremers, D. A.; Lacour, J. L.; Salle B.; Fichet, P.; Vors, E.; Fabre, C.; Dubessy, J.; Maurice, S.

    2004-01-01

    The research project called MALIS (Mars Analysis by Laser-Induced breakdown Spectroscopy) aims at producing a LIBS facility allowing rocks and soils analysis on Mars at stand off distance up to 10 or ideally 20 m. The capability of LIBS to perform a sample analysis at different distances was previously shown. Basically, the LIBS technique uses a pulsed laser beam focused on a sample surface. With sufficient power, the laser ablates the material, producing atoms and ions in an excited state, resulting in a visible spark. This one is characteristic of the elements present in the material. Light emission recording allows the qualitative and the quantitative elemental analysis. Up to now the technique needs a pre calibration in order to obtain quantitative data. But some works indicated that even with a lack of calibration quantitative results can be obtained. Our previous works studied different parameters (laser energy, atmospheric pressure, ...) that are of importance (laser energy, atmospheric pressure, ...) to control the quality of the measurements in Martian conditions. With those optimized parameters, some analytical results were obtained and will be presented.

  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. Laser-Induced Breakdown Spectroscopy (LIBS) in a Novel Molten Salt Aerosol System.

    PubMed

    Williams, Ammon N; Phongikaroon, Supathorn

    2017-04-01

    In the pyrochemical separation of used nuclear fuel (UNF), fission product, rare earth, and actinide chlorides accumulate in the molten salt electrolyte over time. Measuring this salt composition in near real-time is advantageous for operational efficiency, material accountability, and nuclear safeguards. Laser-induced breakdown spectroscopy (LIBS) has been proposed and demonstrated as a potential analytical approach for molten LiCl-KCl salts. However, all the studies conducted to date have used a static surface approach which can lead to issues with splashing, low repeatability, and poor sample homogeneity. In this initial study, a novel molten salt aerosol approach has been developed and explored to measure the composition of the salt via LIBS. The functionality of the system has been demonstrated as well as a basic optimization of the laser energy and nebulizer gas pressure used. Initial results have shown that this molten salt aerosol-LIBS system has a great potential as an analytical technique for measuring the molten salt electrolyte used in this UNF reprocessing technology.

  17. Analysis and classification of heterogeneous kidney stones using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Oztoprak, Belgin Genc; Gonzalez, Jhanis; Yoo, Jong; Gulecen, Turgay; Mutlu, Nazim; Russo, Richard E; Gundogdu, Ozcan; Demir, Arif

    2012-11-01

    Kidney stones were analyzed using laser-induced breakdown spectroscopy (LIBS), utilizing a high resolution multi-channel charge-coupled device (CCD) spectrometer and a nanosecond-pulse Nd : YAG laser. The kidney stones were also characterized using X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques for comparative analysis. It was found that the ratio of hydrogen (H) to carbon (C) was an important indicator of organic compounds such as uric acid. Advantages of LIBS, especially with regards to amount of sample required and sample preparation as well as the ability to carry out elemental analysis and classification of kidney stones simultaneously, over other analytical techniques such as XRD and XRF are discussed. The common minor elements detected in the kidney stones include P, S, Si, Ti, and Zn. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) of broadband LIBS spectra were employed for classifying different types of kidney stones. The results are beneficial in understanding kidney stone formation processes, which can lead to preventive therapeutic strategies and treatment methods for urological patients.

  18. 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.

  19. 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

    2016-02-03

    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.

  20. 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

  1. AdS duals of matrix strings

    NASA Astrophysics Data System (ADS)

    Morales, Jose F.; Samtleben, Henning

    2003-06-01

    We review recent work on the holographic duals of type II and heterotic matrix string theories described by warped AdS3 supergravities. In particular, we compute the spectra of Kaluza-Klein primaries for type I, II supergravities on warped AdS3 × S7 and match them with the primary operators in the dual two-dimensional gauge theories. The presence of non-trivial warp factors and dilaton profiles requires a modification of the familiar dictionary between masses and 'scaling' dimensions of fields and operators. We present these modifications for the general case of domain wall/QFT correspondences between supergravities on warped AdSd+1 × Sq geometries and super Yang-Mills theories with 16 supercharges.

  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. 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

  4. Planetary Surface Analysis Using Fast Laser Spectroscopic Techniques: Combined Microscopic Raman, LIBS, and Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Blacksberg, J.; Rossman, G. R.; Maruyama, Y.; Charbon, E.

    2011-12-01

    In situ exploration of planetary surfaces has to date required multiple techniques that, when used together, yield important information about their formation histories and evolution. We present a time-resolved laser spectroscopic technique that could potentially collect complementary sets of data providing information on mineral structure, composition, and hydration state. Using a picosecond-scale pulsed laser and a fast time-resolved detector we can simultaneously collect spectra from Raman, Laser Induced Breakdown Spectroscopy (LIBS), and fluorescence emissions that are separated in time due to the unique decay times of each process. The use of a laser with high rep rate (40 KHz) and low pulse energy (1 μJ/pulse) allows us to rapidly collect high signal to noise Raman spectra while minimizing sample damage. Increasing the pulse energy by about an order of magnitude creates a microscopic plasma near the surface and enables the collection of LIBS spectra at an unusually high rep rate and low pulse energy. Simultaneously, broader fluorescence peaks can be detected with lifetimes varying from nanosecond to microsecond. We will present Raman, LIBS, and fluorescence spectra obtained on natural mineral samples such as sulfates, clays, pyroxenes and carbonates that are of interest for Mars mineralogy. We demonstrate this technique using a photocathode-based streak camera detector as well as a newly-developed solid state Single Photon Avalanche Diode (SPAD) sensor array based on Complementary Metal-Oxide Semiconductor (CMOS) technology. We will discuss the impact of system design and detector choice on science return of a potential planetary surface mission, with a specific focus on size, weight, power, and complexity. The research described here was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (NASA).

  5. Screening of brick-kiln area soil for determination of heavy metal Pb using LIBS.

    PubMed

    Pandhija, Shiwani; Rai, A K

    2009-01-01

    Rapid measurement of heavy metals in soil is an important factor in modeling the effect of industrial pollution on agricultural soil. Conventional methods of heavy metal analysis are relatively slow in terms of measurement/analysis time and sample preparation time with the requirement of skilled manpower. Our results highlight the quantitative analysis of toxic metal lead (Pb), for the first time, in an Indian agricultural soil, in the vicinity of brick-kiln area, Phaphamau, near Allahabad, India, by using a novel technique named as Laser-induced breakdown spectroscopy (LIBS). LIBS spectra of soil has been recorded in the wavelength range from ultraviolet (UV) to infrared region (200-1,100 nm). The suitability of Pb lines for drawing the calibration curve is checked and realized, for the first time, that 220.3 nm, which is observed in the UV region of LIBS spectra, is completely interference free and best suited for the quantification of trace amount of Pb in soil instead of any other Pb lines, because it has best linear regression coefficient and smallest standard deviation of the background signal. In the present work the detection limit for Pb in soil is found to be 45 ppm. Based on the present work the concentration of Pb in agricultural soil of brick-kiln area in Phaphamau is found to be congruent with 570 ppm, which is more than the regulatory standards imposed by US Environmental Protection Agency (400 ppm) for the presence of lead in soil, therefore, it is of great concern to us.

  6. Accuracy Enhancement of Raman Spectroscopy Using Complementary Laser-Induced Breakdown Spectroscopy (LIBS) with Geologically Mixed Samples.

    PubMed

    Choi, Soojin; Kim, Dongyoung; Yang, Junho; Yoh, Jack J

    2017-01-01

    Quantitative Raman analysis was carried out with geologically mixed samples that have various matrices. In order to compensate the matrix effect in Raman shift, laser-induced breakdown spectroscopy (LIBS) analysis was performed. Raman spectroscopy revealed the geological materials contained in the mixed samples. However, the analysis of a mixture containing different matrices was inaccurate due to the weak signal of the Raman shift, interference, and the strong matrix effect. On the other hand, the LIBS quantitative analysis of atomic carbon and calcium in mixed samples showed high accuracy. In the case of the calcite and gypsum mixture, the coefficient of determination of atomic carbon using LIBS was 0.99, while the signal using Raman was less than 0.9. Therefore, the geological composition of the mixed samples is first obtained using Raman and the LIBS-based quantitative analysis is then applied to the Raman outcome in order to construct highly accurate univariate calibration curves. The study also focuses on a method to overcome matrix effects through the two complementary spectroscopic techniques of Raman spectroscopy and LIBS.

  7. Effect of laser beam parameters on melt mobilization and LIBS analysis of a special aluminum alloy containing zeolite

    NASA Astrophysics Data System (ADS)

    Khalil, Osama M.; Nakimana, Agnes

    2016-07-01

    Aluminum alloy containing zeolite was analyzed by using nanosecond and femtosecond laser-induced breakdown spectroscopy (ns and fs-LIBS). The results reveal that Laser parameters, target physical properties, and ambient conditions affect the laser ablation process. The aluminum silicate minerals present in the alloy under investigation enable material volume expansion under compression. In laser interaction with this alloy, it has been observed that the crater depth decreases with the increase of the surface hardness. In ns -LIBS, it is noted that the ablation speed decreases with time and suddenly decreases with less sharp slope and after that the ablation speed increases slightly. In additional the results show the vanishing and reform of the crater rim with the increase of ablation time. Furthermore, a comparison between ns and fs-LIBS analysis has been done. Ns-LIBS analysis reveals that both spectra intensity and lines detection are significantly influenced by the ambient conditions. However in fs-LIBS, the ambient conditions affect the presented lines amplitude and width with the same effect on all lines.

  8. 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

  9. Calibration-free quantitative analysis of elemental ratios in intermetallic nanoalloys and nanocomposites using Laser Induced Breakdown Spectroscopy (LIBS).

    PubMed

    Davari, Seyyed Ali; Hu, Sheng; Mukherjee, Dibyendu

    2017-03-01

    Intermetallic nanoalloys (NAs) and nanocomposites (NCs) have increasingly gained prominence as efficient catalytic materials in electrochemical energy conversion and storage systems. But their morphology and chemical compositions play critical role in tuning their catalytic activities, and precious metal contents. While advanced microscopy techniques facilitate morphological characterizations, traditional chemical characterizations are either qualitative or extremely involved. In this study, we apply Laser Induced Breakdown Spectroscopy (LIBS) for quantitative compositional analysis of NAs and NCs synthesized with varied elemental ratios by our in-house built pulsed laser ablation technique. Specifically, elemental ratios of binary PtNi, PdCo (NAs) and PtCo (NCs) of different compositions are determined from LIBS measurements employing an internal calibration scheme using the bulk matrix species as internal standards. Morphology and qualitative elemental compositions of the aforesaid NAs and NCs are confirmed from Transmission Electron Microscopy (TEM) images and Energy Dispersive X-ray Spectroscopy (EDX) measurements. LIBS experiments are carried out in ambient conditions with the NA and NC samples drop cast on silicon wafers after centrifugation to increase their concentrations. The technique does not call for cumbersome sample preparations including acid digestions and external calibration standards commonly required in Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) techniques. Yet the quantitative LIBS results are in good agreement with the results from ICP-OES measurements. Our results indicate the feasibility of using LIBS in future for rapid and in-situ quantitative chemical characterizations of wide classes of synthesized NAs and NCs.

  10. Exploration of Mars with the ChemCam LIBS Instrument and the Curiosity Rover

    NASA Technical Reports Server (NTRS)

    Newsom, Horton E.

    2016-01-01

    The Mars Science Laboratory (MSL) Curiosity rover landed on Mars in August 2012, and has been exploring the planet ever since. Dr. Horton E. Newsom will discuss the MSL's design and main goal, which is to characterize past environments that may have been conducive to the evolution and sustainability of life. He will also discuss Curiosity's science payload, and remote sensing, analytical capabilities, and direct discoveries of the Chemistry & Camera (ChemCam) instrument, which is the first Laser Induced Breakdown Spectrometer (LIBS) to operate on another planetary surface and determine the chemistry of the rocks and soils.

  11. 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.

  12. Validation studies of the site-directed docking program LibDock.

    PubMed

    Rao, Shashidhar N; Head, Martha S; Kulkarni, Amit; LaLonde, Judith M

    2007-01-01

    The performance of the site-features docking algorithm LibDock has been evaluated across eight GlaxoSmithKline targets as a follow-up to a broad validation study of docking and scoring software (Warren, G. L.; Andrews, W. C.; Capelli, A.; Clarke, B.; Lalonde, J.; Lambert, M. H.; Lindvall, M.; Nevins, N.; Semus, S. F.; Senger, S.; Tedesco, G.; Walls, I. D.; Woolven, J. M.; Peishoff, C. E.; Head, M. S. J. Med. Chem. 2006, 49, 5912-5931). Docking experiments were performed to assess both the accuracy in reproducing the binding mode of the ligand and the retrieval of active compounds in a virtual screening protocol using both the DJD (Diller, D. J.; Merz, K. M., Jr. Proteins 2001, 43, 113-124) and LigScore2 (Krammer, A. K.; Kirchoff, P. D.; Jiang, X.; Venkatachalam, C. M.; Waldman, M. J. Mol. Graphics Modell. 2005, 23, 395-407) scoring functions. This study was conducted using DJD scoring, and poses were rescored using all available scoring functions in the Accelrys LigandFit module, including LigScore2. For six out of eight targets at least 30% of the ligands were docked within a root-mean-square difference (RMSD) of 2.0 A for the crystallographic poses when the LigScore2 scoring function was used. LibDock retrieved at least 20% of active compounds in the top 10% of screened ligands for four of the eight targets in the virtual screening protocol. In both studies the LigScore2 scoring function enhanced the retrieval of crystallographic poses or active compounds in comparison with the results obtained using the DJD scoring function. The results for LibDock accuracy and ligand retrieval in virtual screening are compared to 10 other docking and scoring programs. These studies demonstrate the utility of the LigScore2 scoring function and that LibDock as a feature directed docking method performs as well as docking programs that use genetic/growing and Monte Carlo driven algorithms.

  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. 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.

  15. 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

  16. 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

  17. 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.

  18. Efficient global optimization based 3D carotid AB-LIB MRI segmentation by simultaneously evolving coupled surfaces.

    PubMed

    Ukwatta, Eranga; Yuan, Jing; Rajchl, Martin; Fenster, Aaron

    2012-01-01

    Magnetic resonance (MR) imaging of carotid atherosclerosis biomarkers are increasingly being investigated for the risk assessment of vulnerable plaques. A fast and robust 3D segmentation of the carotid adventitia (AB) and lumen-intima (LIB) boundaries can greatly alleviate the measurement burden of generating quantitative imaging biomarkers in clinical research. In this paper, we propose a novel global optimization-based approach to segment the carotid AB and LIB from 3D T1-weighted black blood MR images, by simultaneously evolving two coupled surfaces with enforcement of anatomical consistency of the AB and LIB. We show that the evolution of two surfaces at each discrete time-frame can be optimized exactly and globally by means of convex relaxation. Our continuous max-flow based algorithm is implemented in GPUs to achieve high computational performance. The experiment results from 16 carotid MR images show that the algorithm obtained high agreement with manual segmentations and achieved high repeatability in segmentation.

  19. An AdS Crunch in Supergravity

    NASA Astrophysics Data System (ADS)

    Hertog, Thomas

    2004-12-01

    We review some properties of N=8 gauged supergravity in four dimensions with modified, but AdS invariant boundary conditions on the m2 = -2 scalars. There is a one-parameter class of asymptotic conditions on these fields and the metric components, for which the full AdS symmetry group is preserved. The generators of the asymptotic symmetries are finite, but acquire a contribution from the scalar fields. For a large class of such boundary conditions, we find there exist black holes with scalar hair that are specified by a single conserved charge. Since Schwarschild-AdS is a solution too for all boundary conditions, this provides an example of black hole non-uniqueness. We also show there exist solutions where smooth initial data evolve to a big crunch singularity. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity, and we report on a preliminary study of this.

  20. Growth performance, feed digestibility, body composition, and feeding behavior of high- and low-residual feed intake fat-tailed lambs under moderate feed restriction.

    PubMed

    Rajaei Sharifabadi, H; Naserian, A A; Valizadeh, R; Nassiry, M R; Bottje, W G; Redden, R R

    Two experiments were conducted to evaluate the effect of moderate feed restriction on productivity of lambs classified on the basis of phenotypic expression of residual feed intake (RFI). In Exp. 1, 58 fat-tailed Kurdi ram lambs (32.1 ± 4.2 kg BW) were individually fed, ad libitum, a pelleted diet (35% alfalfa hay and 65% concentrate). Feed intake and ADG were determined for a 6-wk period and 3 feed efficiency measures including RFI, G:F, and partial efficiency of maintenance (PEM) were calculated. The lambs were sorted based on RFI and the 16 highest RFI (RFI ≥ mean + 0.5 SD) and 16 lowest RFI (RFI ≤ mean - 0.5 SD) lambs were subjected to body composition (BC) and DM digestibility (DMD) analysis. Feeding behavior traits (FB) were also evaluated for 24 h using a regular 5-min interval observation method. The high- and low-RFI lambs (14 lambs/RFI group) so classified in Exp. 1 were used in Exp. 2. Half of the lambs in each RFI group were randomly selected to be fed ad libitum or 85% of ad libitum (restricted feeding), which resulted in 4 experimental groups: 1) ad libitum high-RFI, 2) feed restricted high-RFI, 3) ad libitum low-RFI, and 4) feed restricted low-RFI. The lambs were fed the same diet as Exp. 1, and growth efficiency during a 6-wk test period as well as BC, DMD, and FB were also determined in Exp. 2. In Exp. 1, the low-RFI lambs consumed 14% ( < 0.01) less feed than high-RFI lambs. Differences were also observed between high- and low-RFI groups for G:F ( = 0.01), RFI ( < 0.01), and PEM ( < 0.01) in Exp. 1, but no differences were detected between high- and low-RFI lambs for ADG ( = 0.79), DMD ( = 0.42), BC ( > 0.72), and FB ( > 0.24). In Exp.2, the restriction feeding regime negatively affected ADG ( < 0.01) and G:F ( = 0.02) in low-RFI lambs, whereas G:F ( = 0.02) and PEM ( < 0.01) were improved in high-RFI lambs under the feed restriction condition. No effects of feed restriction on DMD ( = 0.87) and BC ( > 0.05) were observed. The lambs fed at

  1. [Infant feeding].

    PubMed

    Robert, M

    2012-09-01

    Infants are vulnerable: their growth and their development depend largely on their nutritional status. It is important to propose for them an optimal food. The human milk is unquestionably the best choice for the infant. When breastfeeding is not possible, the choice of the milk is made among hundreds of formulas for infants. They are regulated by a European directive. The healthcare professionals have to recommend as often as possible an infant formula: low protein content, predominance of whey proteins, enrichment with long chain fatty acids, lactose, addition of pre- or probiotics. The formulas for specific indications will be recommended in case of particular situations after verification that the complaints (constipation, regurgitations, stomach pains) cannot be corrected by simple dietary measures (increasing of the intakes of meals with a concomitant reduction of the volume of the meals). The food diversification is recommended between 17 and 26 weeks according to the neuromuscular capacities of the infant. These meals must be presented with a spoon to assure a sufficient nutritional intake. In Belgium, the use is to begin with fruits. One should avoid adding biscuits or sugar. The meal of vegetables will be introduced a little later. It should consist of starchy foods, vegetables with some fat to which the meat will be added. Numerous foods (biscuits, croissants and similar products, chips) should never be part of the ordinary menu, but should be reserved for particular occasions. The education of the children should begin from this age on.

  2. 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

  3. [Analysis of Cr in soil by LIBS based on conical spatial confinement of plasma].

    PubMed

    Lin, Yong-Zeng; Yao, Ming-Yin; Chen, Tian-Bing; Li, Wen-Bing; Zheng, Mei-Lan; Xu, Xue-Hong; Tu, Jian-Ping; Liu, Mu-Hua

    2013-11-01

    The present study is to improve the sensitivity of detection and reduce the limit of detection in detecting heavy metal of soil by laser induced breakdown spectroscopy (LIBS). The Cr element of national standard soil was regarded as the research object. In the experiment, a conical cavity with small diameter end of 20 mm and large diameter end of 45 mm respectively was installed below the focusing lens near the experiment sample to mainly confine the signal transmitted by plasma and to some extent to confine the plasma itself in the LIBS setup. In detecting Cr I 425.44 nm, the beast delay time gained from experiment is 1.3 micros, and the relative standard deviation is below 10%. Compared with the setup of non-spatial confinement, the spectral intensity of Cr in the soil sample was enhanced more than 7%. Calibration curve was established in the Cr concentration range from 60 to 400 microg x g(-1). Under the condition of spatial confinement, the liner regression coefficient and the limit of detection were 0.997 71 and 18.85 microg x g(-1) respectively, however, the regression coefficient and the limit of detection were 0.991 22 and 36.99 microg x g(-1) without spatial confinement. So, this shows that conical spatial confinement can/improve the sensitivity of detection and enhance the spectral intensity. And it is a good auxiliary function in detecting Cr in the soil by laser induced breakdown spectroscopy.

  4. Request for observations of GW Lib and V842 Cen in support of HST observations

    NASA Astrophysics Data System (ADS)

    Templeton, Matthew R.

    2010-03-01

    Dr. Paula Szkody (U. Washington) has requested the help of AAVSO observers to provide monitoring of the cataclysmic variables GW Lib and V842 Cen in support of Hubble Space Telescope observations in March 2010. Observations of both objects are requested beginning immediately, with intensive observations requested beginning 48 hours prior to the scheduled HST visit. The first observation of GW Lib has now been scheduled for 2010 March 11 03:45 UT; intensive observations by the AAVSO community are requested beginning 2010 March 9 UT. Observations of V842 Cen are expected to be scheduled during the dates of 2010 March 18-22. Observations of both sources are requested to guarantee to ground controllers at STScI that they are below V~14.0 which is considered the safe limit for the Cosmic Origins Spectrograph. Positive observations are preferred if at all possible, however any fainter-than below V=14 is useful. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.

  5. 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.

  6. Study of filtering Ag liquid sample by chitosan biomembrane using laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Rupiasih, Ni Nyoman; Suyanto, Hery; Sumadiyasa, Made; Purwanto, Christine Prita; Purnomo, Rendra Rustam

    2013-09-01

    The capability of Laser-Induced Breakdown Spectroscopy (LIBS) to resolve filtration process of Ag liquid sample by chitosan biomembrane is demonstrated. The biomembrane was prepared by inversion method used to filter Ag liquid using pressurized technique samples which were then analyzed by monitoring the emission corresponding to Ag (I) at wavelength of 328 nm. The experiment was conducted by varying the laser energy i.e. 80, 120, and 160 mJ, where, subsequently, and its effect on the depth-profile from 20 - 200 μm was characterized by LIBS. The results showed that the physical processes of pressurized filtration led a homogeneous Ag in the membrane from the surface to a depth of 200 μm. The optimum condition was obtained at laser energy of 120 mJ. The adsorption occurred only on the surface of the membrane i.e. 20 μm depth, but there was no inclusion. Improvement of the detection performance of adsorption process was done by heating the dripped membrane at 35 °C and was resulting in increase in emission intensity as expected.

  7. 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.

  8. Development of a Stand-off Laser Induced Breakdown Spectroscopy (ST-LIBS) system for the analysis of complex matrices

    NASA Astrophysics Data System (ADS)

    Tamboli, M. M.; Unnikrishnan, V. K.; Nayak, R.; Devangad, P.; Muhammed Shameem, K. M.; Kartha, V. B.; Santhosh, C.

    2016-08-01

    In the present work, we discuss the evaluation and optimization of a stand-off laser induced breakdown spectroscopy (ST-LIBS) system, developed indigenously for remote analysis of heavy elements in soil. A compact Q-switched Nd:YAG laser operating at fundamental wavelength 1064 nm was used for plasma generation at distances up to 6 meters. Techniques for optimal experimental results were evaluated for detection of Cd, Cr, Pb, Mo and Ni in soil. The system was evaluated with two NIST certified soil samples. The effect of working distance on the LIBS signal is also discussed briefly. Results confirm the capabilities of the system for remote monitoring.

  9. 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…

  10. Dynamics of the Linuron Hydrolase libA Gene Pool Size in Response to Linuron Application and Environmental Perturbations in Agricultural Soil and On-Farm Biopurification Systems

    PubMed Central

    Bers, Karolien; Sniegowski, Kristel; De Mot, René

    2012-01-01

    libA, a gene encoding a novel type of linuron hydrolase, was recently identified in the linuron-mineralizing Variovorax sp. strain SRS16. In order to assess the contribution of libA to linuron degradation in environmental settings, libA abundance was monitored in response to the application of linuron and to environmental perturbations in agricultural soil microcosms and microcosms simulating the matrix of on-farm biopurification systems. libA numbers were measured by real-time PCR and linked to reported data of Variovorax community composition and linuron mineralization capacity. In the soil microcosms and one biopurification system setup, libA numbers responded to the application of linuron and environmental changes in congruency with the modulation of linuron mineralization capacity and the occurrence of a particular Variovorax phylotype (phylotype A). However, in another biopurification system setup, no such correlations were found. Our data suggest that in the simulated environmental settings, the occurrence of libA can be linked to the linuron mineralization capacity and that libA is primarily hosted by Variovorax phylotype A strains. However, the results also suggest that, apart from libA, other, as-yet-unknown isofunctional genes play an important role in linuron mineralization in the environment. PMID:22307296

  11. Mid-infrared, long wave infrared (4-12 μm) molecular emission signatures from pharmaceuticals using laser-induced breakdown spectroscopy (LIBS).

    PubMed

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

    2014-01-01

    In an effort to augment the atomic emission spectra of conventional laser-induced breakdown spectroscopy (LIBS) and to provide an increase in selectivity, mid-wave to long-wave infrared (IR), LIBS studies were performed on several organic pharmaceuticals. Laser-induced breakdown spectroscopy signature molecular emissions of target organic compounds are observed for the first time in the IR fingerprint spectral region between 4-12 μm. The IR emission spectra of select organic pharmaceuticals closely correlate with their respective standard Fourier transform infrared spectra. Intact and/or fragment sample molecular species evidently survive the LIBS event. The combination of atomic emission signatures derived from conventional ultraviolet-visible-near-infrared LIBS with fingerprints of intact molecular entities determined from IR LIBS promises to be a powerful tool for chemical detection.

  12. Standoff Laser-Induced Breakdown Spectroscopy (LIBS) using a Miniature Wide Field of View Spatial Heterodyne Spectrometer with Sub-Microsteradian Collection Optics.

    PubMed

    Barnett, Patrick D; Lamsal, Nirmal; Angel, S Michael

    2017-01-01

    A spatial heterodyne spectrometer (SHS) is described for standoff laser-induced breakdown spectroscopy (LIBS) measurements. The spatial heterodyne LIBS spectrometer (SHLS) is a diffraction grating based interferometer with no moving parts that offers a very large field of view, high light throughput, and high spectral resolution in a small package. The field of view of the SHLS spectrometer is shown to be ∼1° in standoff LIBS measurements. In the SHLS system described here, the collection aperture was defined by the 10 mm diffraction gratings in the SHS and standoff LIBS measurements were made up to 20 m with no additional collection optics, corresponding to a collection solid angle of 0.2 μsr, or f/2000, and also using a small telescope to increase the collection efficiency. The use of a microphone was demonstrated to rapidly optimize laser focus for 20 m standoff LIBS measurements.

  13. 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.

  14. Request for observations of GW Lib in support of HST observations

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2011-03-01

    Dr. Paula Szkody (University of Washington) has requested AAVSO help in monitoring the cataclysmic variable GW Lib for HST observations scheduled during the week of 2011 April 7-11 UT. Dr. Szkody also observed this object with HST in March 2010 (see AAVSO Alert Notice 417). AAVSO observations are needed to ensure that the object is not in outburst when observed with HST, as it could damage the instrument if it were to go into outburst. AAVSO observations will be used to make a go/no go decision when the observing window opens, and will also be used in the analysis of the resulting data. At the end of March the schedulers will give Dr. Szkody the exact date of the HST observations, and an AAVSO Special Notice will be issued. Dr. Szkody requests nightly monitoring of this object from now until the observing window opens, intensive monitoring during the 24-48 hour period during which observations will be made, and nightly observations for the week following the HST observations. GW Lib is part of a larger study of pulsating white dwarf primaries in cataclysmic variables. In particular, Szkody and collaborators are investigating the effects that higher temperatures and larger rotation velocities caused by accretion have on the pulsation behavior. In these HST observations, they plan to measure the temperature of the white dwarf at minimum. GW Lib is magnitude ~16.8 visual/unfiltered. V filter is preferred for CCD observations, but B, Rc, and Ic may also be used. Detection of the variable itself is not required unless you can reach V=16.8 in reasonable time, but please use sufficient exposure to detect at least the V=143 comparison star or V=147 with a S/N of 10 and report the observation as a "fainter-than" observation. Finder charts with sequence may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. See full Alert Notice for more details.

  15. 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.

  16. AdS2 holographic dictionary

    NASA Astrophysics Data System (ADS)

    Cvetič, Mirjam; Papadimitriou, Ioannis

    2016-12-01

    We construct the holographic dictionary for both running and constant dilaton solutions of the two dimensional Einstein-Maxwell-Dilaton theory that is obtained by a circle reduction from Einstein-Hilbert gravity with negative cosmological constant in three dimensions. This specific model ensures that the dual theory has a well defined ultraviolet completion in terms of a two dimensional conformal field theory, but our results apply qualitatively to a wider class of two dimensional dilaton gravity theories. For each type of solutions we perform holographic renormalization, compute the exact renormalized one-point functions in the presence of arbitrary sources, and derive the asymptotic symmetries and the corresponding conserved charges. In both cases we find that the scalar operator dual to the dilaton plays a crucial role in the description of the dynamics. Its source gives rise to a matter conformal anomaly for the running dilaton solutions, while its expectation value is the only non trivial observable for constant dilaton solutions. The role of this operator has been largely overlooked in the literature. We further show that the only non trivial conserved charges for running dilaton solutions are the mass and the electric charge, while for constant dilaton solutions only the electric charge is non zero. However, by uplifting the solutions to three dimensions we show that constant dilaton solutions can support non trivial extended symmetry algebras, including the one found by Compère, Song and Strominger [1], in agreement with the results of Castro and Song [2]. Finally, we demonstrate that any solution of this specific dilaton gravity model can be uplifted to a family of asymptotically AdS2 × S 2 or conformally AdS2 × S 2 solutions of the STU model in four dimensions, including non extremal black holes. The four dimensional solutions obtained by uplifting the running dilaton solutions coincide with the so called `subtracted geometries', while those obtained

  17. 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…

  18. Review of methodological and experimental LIBS techniques for coal analysis and their application in power plants in China

    NASA Astrophysics Data System (ADS)

    Zhao, Yang; Zhang, Lei; Zhao, Shu-Xia; Li, Yu-Fang; Gong, Yao; Dong, Lei; Ma, Wei-Guang; Yin, Wang-Bao; Yao, Shun-Chun; Lu, Ji-Dong; Xiao, Lian-Tuan; Jia, Suo-Tang

    2016-12-01

    Laser-induced breakdown spectroscopy (LIBS) is an emerging analytical spectroscopy technique. This review presents the main recent developments in China regarding the implementation of LIBS for coal analysis. The paper mainly focuses on the progress of the past few years in the fundamentals, data pretreatment, calibration model, and experimental issues of LIBS and its application to coal analysis. Many important domestic studies focusing on coal quality analysis have been conducted. For example, a proposed novel hybrid quantification model can provide more reproducible quantitative analytical results; the model obtained the average absolute errors (AREs) of 0.42%, 0.05%, 0.07%, and 0.17% for carbon, hydrogen, volatiles, and ash, respectively, and a heat value of 0.07 MJ/kg. Atomic/ionic emission lines and molecular bands, such as CN and C2, have been employed to generate more accurate analysis results, achieving an ARE of 0.26% and a 0.16% limit of detection (LOD) for the prediction of unburned carbon in fly ashes. Both laboratory and on-line LIBS apparatuses have been developed for field application in coal-fired power plants. We consider that both the accuracy and the repeatability of the elemental and proximate analysis of coal have increased significantly and further efforts will be devoted to realizing large-scale commercialization of coal quality analyzer in China.

  19. Spatial investigation of plasma emission from laminar diffusion methanol, ethanol, and n-propanol alcohol flames using LIBS method

    NASA Astrophysics Data System (ADS)

    Ghezelbash, Mahsa; Majd, Abdollah Eslami; Darbani, Seyyed Mohammad Reza; Mousavi, Seyyed Jabbar; Ghasemi, Ali; Tehrani, Masoud Kavosh

    2017-01-01

    Laser-induced breakdown spectroscopy (LIBS) technique is used to record some plasma emissions of different laminar diffusion methanol, ethanol, and n-propanol alcohol flames, to investigate the shapes, structures (i.e., reactants and products zones), kind, and quality of burning in different areas. For this purpose, molecular bands of CH, CH*, C2, CN, and CO as well as atomic and ionic lines of C, H, N, and O are identified, simultaneously. Experimental results indicate that the CN and C2 emissions have highest intensity in LIBS spectrum of n-propanol flame and the lowest in methanol. In addition, lowest content of CO pollution and better quality of burning process in n-propanol fuel flame toward ethanol and methanol are confirmed by comparison between their CO molecular band intensities. Moreover, variation of the signal intensity from these three flames with that from a known area of burner plate is compared. Our findings in this research advance the prior results in time-integrated LIBS combustion application and suggesting that LIBS can be used successfully with the CCD detector as a non-gated analytical tool, given its simple instrumentation needs, real-time capability applications of molecular detection in laminar diffusion flame samples, requirements.

  20. 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.

  1. 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)

  2. "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…

  3. 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…

  4. 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…

  5. 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

  6. 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.

  7. 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.

  8. Geochemical Predictions of Elemental Compositions using Remote LIBS under Mars Conditions

    NASA Astrophysics Data System (ADS)

    Dyar, M. D.; Tucker, J.; Humphries, S.; Clegg, S. M.; Wiens, R. C.; Carmosino, M. L.

    2010-12-01

    The ChemCam instrument on Mars Science Laboratory will be the first deployment of laser-induced breakdown spectroscopy (LIBS) for remote geochemical analysis. Successful quantitative analyses of those results will use in-situ calibration targets and laboratory calibrations, and employ sophisticated algorithms for data reduction in order to correct for variations in peak intensities and areas caused by interactions in the plasma that are a function of chemical composition. Such chemical matrix effects influence the ratio of each emission line to the abundance of the element that produces it, and are directly related to the elemental composition of the sample. Advances in statistical analysis of LIBS data that mitigate matrix effects and provide for accurate and precise bulk analysis of major, minor, and trace elements are reported here. Our in-house data set currently includes LIBS spectra of >140 rock powders (igneous, metamorphic, and sedimentary) with highly-varying compositions (as determined by XRF) that were acquired at 7-9 m standoff distance under Mars atmospheric conditions using a laboratory instrument [1]. LIBS spectra were modeled using partial least squares analysis (PLS) to predict elemental compositions. Within the igneous suite, 10 repeat measurements of a single sample demonstrates consistency and precision; calculated 1-σ errors were 1.6 wt.%SiO2, 1.5 wt.% Al2O3, 0.4 wt.% TiO2, 1.2 wt.% Fe2O3T, 1.6 wt.% MgO, 0.02 wt.% MnO, 1.1 wt.% CaO, 0.5 wt.% Na2O, 0.2 wt.% P2O5, and 0.4 wt.% K2O. In the overall suite, predictions of all elements, expressed as root mean square errors (RMSEP), are better than ±2.45 for SiO2, ±1.64 for Al2O3, ±0.38 for TiO2, ±1.50 for Fe2O3T, ±1.88 for MgO, ±0.03 for MnO, ±0.82 for CaO, ±0.55 for K2O, ±0.62 for Na2O, and ±0.24 for P2O5 in units of wt.% oxides. On-going work should reduce these values even further. For elements at low concentrations, multivariate analyses must be interpreted with care because their

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Effect of experimental conditions on surface hardness measurements of calcified tissues via LIBS

    NASA Astrophysics Data System (ADS)

    Abdel-Salam, Z. A.; Nanjing, Z.; Anglos, D.; Harith, M. A.

    2009-01-01

    This paper reports on the effects of LIBS experimental conditions on the measurement of the surface hardness of calcified tissues. The technique mainly depends on a previously demonstrated correlation between the intensity ratio of ionic to atomic spectral lines and the hardness of the target material. Three types of calcified tissues have been examined, namely enamel of human teeth, shells, and eggshells. Laser-induced breakdown spectra were obtained under two different experimental conditions. In the first nano and picoseconds, laser pulses were used in a single-pulse arrangement, while in the second, single- and double-pulse regimes with nanosecond laser excitation were utilized. The results show that the ionic to atomic spectral line intensity ratios are higher in the case of picosecond laser pulse for both Ca and Mg spectral lines. This effect has been justified in view of the repulsive force of the laser-induced shock waves which depends clearly on the target surface hardness and on the laser irradiance. The electron densities ratio (pico/nano) is shown to be strongly depending on the laser irradiance too. In the case of calcium, single-pulse ratios are higher than the double-pulse ratios, while there is no appreciable difference between both in the case of magnesium. The results obtained herein suggest that double-pulse nanosecond arrangement and the choice of a minor element such as Mg furnishes the best experimental conditions for estimating the surface hardness via LIBS spectra. To validate this method, it has been applied on two previously measured groups of teeth enamel, the first is of ancient Egyptians, and the second from Nubians and Ugandans. The results support the usefulness of this method for similar real-life applications.

  14. Determination of trace elements in volcanic rock samples collected from cenozoic lava eruption sites using LIBS.

    PubMed

    Gondal, Mohammed A; Nasr, Mohamed M; Ahmed, Zulfiqar; Yamani, Zain H

    2009-04-01

    Trace elements of environmental significance present in the volcanic rock samples collected from sites of the Cenozoic era flood basalt flows and eruptions were detected using locally developed laser-induced breakdown spectrometer. For spectro-chemical analysis of these samples, the plasma was generated by focusing a pulsed Nd: YAG laser radiation at 1064 nm wavelength on the target rock samples. These samples were collected from four widely separated locations surrounding the volcanic eruption sites belonging to the Harrat Hutaymah volcanic field in the vicinity of Taba town, situated to the east of Hail city of northern Saudi Arabia. These samples represent the scoria basalt lava flows as well as a large tuff-ring crater and it contains xenoliths. These flows occur widespread over the Earth's surface in this region, and their contained xenoliths are brought up from depths of a few tens of kilometers. This volcanic field has received much less attention in the previous geological studies; and consequently, its effects on the environment are not well defined. The concentration of different elements of environmental significance like Cr, Pb, Mn, Cd, Sr and other trace metals like Cu, Al, Ca, Mg, Zn, Ti and Fe in these rock samples were determined by spectral analysis. Parametric dependence for improvement of LIBS sensitivity for detection of these elements was also carried out. The highest concentration detected of environmentally significant elements like Cr, Mn, Pb, Sr and Ni are 1910, 1399, 90.5, 12412 and 461.5 ppm, respectively in four different lava samples which are considered to be much higher than the safe permissible limits. The LIBS results were compared with the results obtained using other analytical techniques such as the inductively coupled plasma atomic emission spectroscopy (ICP-AES).

  15. 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

  16. Application of laser-induced breakdown spectroscopy (LIBS) as a tool to determine the origin of 'conflict minerals'

    NASA Astrophysics Data System (ADS)

    Hark, R. R.; Harmon, R. S.; Remus, J. J.; East, L. J.; Wise, M. A.; Tansi, B. M.; Shughrue, K. M.; Dunsin, K. S.; Liu, C.

    2012-04-01

    Laser-induced breakdown spectroscopy (LIBS) offers a means of rapidly distinguishing different places of origin for a mineral because the LIBS plasma emission spectrum provides the complete chemical composition (i.e. geochemical fingerprint) of a mineral in real-time. An application of this approach with potentially significant commercial and political importance is the spectral fingerprinting of the 'conflict minerals' columbite-tantalite ("coltan"). Following a successful pilot study of three columbite-tantalite suites from the United States and Canada, a more geographically diverse set of samples from 37 locations worldwide were analyzed using a commercial laboratory LIBS system and a subset of samples also analyzed using a prototype broadband field-portable system. The spectral range from 250-490 nm was chosen for the laboratory analysis to encompass many of the intense emission lines for the major elements (Ta, Nb, Fe, Mn) and the significant trace elements (e.g., W, Ti, Zr, Sn, U, Sb, Ca, Zn, Pb, Y, Mg, and Sc) known to commonly substitute in the columbite-tantalite solid solution series crystal structure and in the columbite group minerals. The field-portable instrument offered an increased spectral range (198-1005 nm), over which all elements have spectral emission lines, and higher resolution than the laboratory instrument. In both cases, the LIBS spectra were analyzed using advanced multivariate statistical signal processing techniques. Partial Least Squares Discriminant Analysis (PLSDA) resulted in a correct place-level geographic classification at success rates between 90 and 100%. The possible role of rare-earth elements (REE's) as a factor contributing to the high levels of sample discrimination was explored. Given the fact that it can be deployed as a man-portable analytical technology, these results lend additional evidence that LIBS has the potential to be utilized in the field as a real-time tool to discriminate between columbite-tantalite ores of

  17. In-situ 1-D and 2-D mapping of soil core and rock samples using the LIBS long spark

    SciTech Connect

    Rodolfa, C. T.; Cremers, D. A.; Ebinger, M. H.

    2004-01-01

    LIBS is being developed for stand-off interrogation of samples up to 20 m from a lander or rover. Stand-off capability is important to access targets not conveniently located for in-situ analysis. On the other hand, in-situ techniques are still important and are being developed for future missions such as MSL. Retrieved samples may consist of loose soils, subsurface soil cores, drilled rock cores, and ice cores. For these sample types, it is possible to employ LIBS analysis and take advantage of LIBS capabilities. These include: (1) rapid analysis, (2) good detection sensitivity for many elements, (3) good spatial resolution (3-100 microns), and (4) ability to clean a surface prior to analysis. Using LIBS, it is possible to perform a 1-dimensional analysis, for example, determining element concentrations along a soil core, or a 2-dimensional mapping of the sample surface using a unique 'long' spark. Two-dimensional sampling has been developed previously by focusing the laser pulses as small spots on the sample and then moving the sample a short distance between sampling locations. Although demonstrated, this method is time consuming, requiring a large number of shots to span even a small region (for 3 micron resolution, an area 600 x 480 microns sampled in {approx} 30 min using a 20 Hz laser). For a spacecraft instrument, the ability to more rapidly prepare a 2D elemental spatial map will be desirable. Here they discuss the use of LIBS for sampling along a core in 1D (detection of carbon) and for 2D mapping of a rock face.

  18. Short communication: Diurnal feeding pattern of lactating dairy cows.

    PubMed

    DeVries, T J; von Keyserlingk, M A G; Beauchemin, K A

    2003-12-01

    The objectives of this research were to: 1) describe the diurnal variation in feed alley attendance patterns of lactating dairy cows, 2) describe the sources of variation in these patterns, and 3) determine the effects of altering the feed push-up schedule on these patterns. An electronic monitoring system was used to record individual cow presence (6-s resolution) at the feed alley for 24 cows housed in a free-stall barn. Cows were subjected to 2 feeding schedules: 1) baseline schedule, where cows were fed at 0600 and 1515 h and feed was pushed closer to the cows at 1100 and 2130 h; and 2) experimental schedule, where 2 additional feed push-ups at 0030 and 0330 h were added to the baseline schedule. With the data collected from the monitoring system, description of the feed alley attendance patterns on a per minute basis of the group of cows was undertaken. Feed alley attendance was consistently higher during the day and early evening compared with the late night and early morning hours. The greatest percentage of cows attending the feed alley was seen after the delivery of fresh feed and the return from milking. The addition of extra feed push-ups in the early morning hours did little to increase feeding activity. It can be concluded that milking and delivery of fresh feed had a much greater affect on the diurnal pattern of feed alley attendance than did the feed push-ups.

  19. 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...

  20. AD(H)D.

    PubMed

    Harrison, Christopher; Charles, Janice; Britt, Helena

    2008-06-01

    The BEACH program (Bettering the Evaluation and Care of Health) shows that management of attention deficit (hyperactivity) disorder (AD(H)D) was rare in general practice, occurring only six times per 1,000 encounters with children aged 5-17 years, between April 2000 and December 2007. This suggests that general practitioners manage AD(H)D about 46,000 times for this age group nationally each year.

  1. 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.

  2. 21 CFR 573.380 - Ethoxyquin in animal feeds.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... oxidation of carotene, xanthophylls, and vitamins A and E in animal feed and fish food and, (2) as an aid in... added to retard the oxidative destruction of carotene, xanthophylls, and vitamins A and E.”...

  3. 21 CFR 573.380 - Ethoxyquin in animal feeds.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... oxidation of carotene, xanthophylls, and vitamins A and E in animal feed and fish food and, (2) as an aid in... added to retard the oxidative destruction of carotene, xanthophylls, and vitamins A and E.”...

  4. 21 CFR 573.380 - Ethoxyquin in animal feeds.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... oxidation of carotene, xanthophylls, and vitamins A and E in animal feed and fish food and, (2) as an aid in... added to retard the oxidative destruction of carotene, xanthophylls, and vitamins A and E.”...

  5. 21 CFR 573.380 - Ethoxyquin in animal feeds.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... oxidation of carotene, xanthophylls, and vitamins A and E in animal feed and fish food and, (2) as an aid in... added to retard the oxidative destruction of carotene, xanthophylls, and vitamins A and E.”...

  6. 21 CFR 573.380 - Ethoxyquin in animal feeds.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... oxidation of carotene, xanthophylls, and vitamins A and E in animal feed and fish food and, (2) as an aid in... added to retard the oxidative destruction of carotene, xanthophylls, and vitamins A and E.”...

  7. Impact socio professionnel de la libération chirurgicale du syndrome du canal carpien

    PubMed Central

    Kraiem, Aouatef Mahfoudh; Hnia, Hajer; Bouzgarrou, Lamia; Henchi, Mohamed Adnène; Khalfallah, Taoufik

    2016-01-01

    L’objectif de notre travail était d’étudier les conséquences socioprofessionnelles d’une libération chirurgicale du SCC. Il s’agit d’une étude transversale portant sur les sujets opérés pour un SCC d’origine professionnelle ; recensés dans le Service de Médecine de Travail et de Pathologies Professionnelles au CHU Tahar Sfar de Mahdia en Tunisie sur une période de 8 ans allant du 1 Janvier 2006 au mois Décembre 2013. Le recueil des données s’est basé sur une fiche d’enquête, portant sur la description des caractéristiques socioprofessionnelles, médicales, et sur le devenir professionnel des participants. Pour étudier les contraintes psychosociales au travail, nous avons adopté le questionnaire de Karasek. La durée d’arrêt de travail après libération chirurgicale du SCC était significativement liée à l’existence d’autres troubles musculo-squelettiques autre que le SCC, la déclaration du SCC en maladie professionnelle et à l’ancienneté professionnelle des salariés. Quant au devenir professionnel des salariés opérés, 50,7% ont gardé le même poste, 15,3% ont bénéficié d’un aménagement de poste et 33,8% ont bénéficié d’un changement de poste dans la même entreprise. Le devenir professionnel de ces salariés était corrélé à leurs qualifications professionnelles et au type de l’atteinte sensitive et/ou motrice du nerf médian à l’EMG. Un certain nombre de facteurs non lésionnels déterminaient la durée de l’arrêt de travail, alors que le devenir professionnel des opérés pour SCC dépendait essentiellement de leurs qualifications professionnelles et des données de l’électromyogramme. Il est certain que des travaux beaucoup plus larges permettraient d’affiner encore ces résultats. PMID:27800089

  8. [Study on the multivariate quantitative analysis method for steel alloy elements using LIBS].

    PubMed

    Gu, Yan-hong; Li, Ying; Tian, Ye; Lu, Yuan

    2014-08-01

    Quantitative analysis of steel alloys was carried out using laser induced breakdown spectroscopy (LIBS) taking into account the complex matrix effects in steel alloy samples. The laser induced plasma was generated by a Q-switched Nd:YAG laser operating at 1064 nm with pulse width of 10 ns and repeated frequency of 10 Hz. The LIBS signal was coupled to the echelle spectrometer and recorded by a high sensitive ICCD detector. To get the best experimental conditions, some parameters, such as the detection delay, the CCDs integral gate width and the detecting position from the sample surface, were optimized. The experimental results showed that the optimum detection delay time was 1.5 micros, the optimal CCDs integral gate width was 2 micros and the best detecting position was 1.5 mm below the alloy sample's surface. The samples used in the experiments are ten standard steel alloy samples and two unknown steel alloy samples. The quantitative analysis was investigated with the optimum experimental parameters. Elements Cr and Ni in steel alloy samples were taken as the detection targets. The analysis was carried out with the methods based on conditional univariate quantitative analysis, multiple linear regression and partial least squares (PLS) respectively. It turned out that the correlation coefficients of calibration curves are not very high in the conditional univariate calibration method. The analysis results were obtained with the unsatisfied relative errors for the two predicted samples. So the con- ditional univariate quantitative analysis method can't effectively serve the quantitative analysis purpose for multi-components and complex matrix steel alloy samples. And with multiple linear regression method, the analysis accuracy was improved effectively. The method based on partial least squares (PLS) turned out to be the best method among all the three quantitative analysis methods applied. Based on PLS, the correlation coefficient of calibration curve for Cr is 0

  9. 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.

  10. [The symmetric zero-area conversion adptive peak-seeking method research for LIBS/Raman spectra].

    PubMed

    Bi, Yun-Feng; Li, Ying; Zheng, Rong-Er

    2013-02-01

    Automatic peak seeking is an indispensable link for in situ and real-time spectral detection and analysis, and has important significance for application of spectral technology to such fields as long-term marine monitoring and oil mud logging. Based on some typical LIBS/Raman spectrum data obtained from lab, three kinds of symmetric zero-area transformation functions respectively constructed from Gaussian, Lorentz and Voigt function were compared, and the results show that there exists an optimal symmetrical zero-area transformation function for peak seeking, but all the transformation functions obtain the same peak position and peak width under their optimal parameters. The proposed method is free from spectrum background and baseline trend influence, adaptive to the wide range of SNR, close to or even better than artificial recognition for weak peak, and could be used in future automatic in-situ analysis of LIBS and Raman.

  11. Analysis of waste electrical and electronic equipment (WEEE) using laser induced breakdown spectroscopy (LIBS) and multivariate analysis.

    PubMed

    Ángel Aguirre, Miguel; Hidalgo, Montserrat; Canals, Antonio; Nóbrega, Joaquim A; Pereira-Filho, Edenir R

    2013-12-15

    This study shows the application of laser induced breakdown spectroscopy (LIBS) for waste electrical and electronic equipment (WEEE) investigation. Several emission spectra were obtained for 7 different mobiles from 4 different manufacturers. Using the emission spectra of the black components it was possible to see some differences among the manufacturers and some emission lines from organic elements and molecules (N, O, CN and C2) led to the highest contribution for this differentiation. Some polymeric internal parts in contact with the inner pieces of the mobiles and covered with a special paint presented a strong emission signal for Cr. The white pieces presented mainly Al, Ba and Ti in their composition. Finally, this study developed a procedure for LIBS emission spectra using chemometric strategies and suitable information can be obtained for identification of manufacturer and counterfeit products. In addition, the results obtained can improve the classification for establishing recycling strategies of e-waste.

  12. 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

  13. LibME-automatic extraction of 3D ligand-binding motifs for mechanistic analysis of protein-ligand recognition.

    PubMed

    He, Wei; Liang, Zhi; Teng, MaiKun; Niu, LiWen

    2016-12-01

    Identifying conserved binding motifs is an efficient way to study protein-ligand recognition. Most 3D binding motifs only contain information from the protein side, and so motifs that combine information from both protein and ligand sides are desired. Here, we propose an algorithm called LibME (Ligand-binding Motif Extractor), which automatically extracts 3D binding motifs composed of the target ligand and surrounding conserved residues. We show that the motifs extracted by LibME for ATP and its analogs are highly similar to well-known motifs reported by previous studies. The superiority of our method to handle flexible ligands was also demonstrated using isocitric acid as an example. Finally, we show that these motifs, together with their visual exhibition, permit better investigating and understanding of protein-ligand recognition process.

  14. The detection of palladium particles in proton exchange membrane fuel-cell water by laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Snyder, Stuart C; Wickun, William G; Mode, Jeremy M; Gurney, Brian D; Michels, Fred G

    2011-06-01

    Laser-induced breakdown spectroscopy (LIBS) using conditional data analysis was applied to aqueous suspensions of palladium particles in the reformate water of palladium-based proton exchange membrane fuel cells. A significant amount of palladium was found in the water, indicating degradation of the fuel-cell cathode catalytic layers. The palladium particle-size detection limit was found to be about 400 nm. Calibration procedures to quantify the palladium concentration are discussed.

  15. 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.

  16. [Current views on breast feeding].

    PubMed

    Grüttner, R

    1983-07-01

    One of the greatest advantages of feeding exclusively breast-milk is the continuous provision of immunoglobulin A, especially during the first days of life, and of leucocytes with macrophage function as well as unspecific, antiinfectious agents like lactoferrin, lysozyme and neuraminic acid. It seems, that the organism is protected against allergic reactions at the mucosa level of the small intestine caused by the penetration of "foreign" protein by feeding exclusively breast-milk especially during the first weeks and months of life. During the first months of the infant's life an increased supply of iron results from the higher content of iron in breast-milk as compared to cow's milk, and the better absorption of the iron from breast-milk. Just because of this (the better provision with iron from natural food) solid foods should not be added to the infant's diet before 6 months of age. One of the disadvantages of breast-feeding is the passage of unwanted substances from breast-milk to the infant. First of all the chlorinated hydrocarbons have to be mentioned within this context. However, a decreasing tendency can be assumed according to recent investigations. An increasing tendency in breast-milk, though not confirmed, seems possible only for the polychlorinated biphenyls. Nevertheless, for the pediatrician no reason to advise against breast-feeding results from the unwanted admixtures of chlorinated hydrocarbons in breast-milk. One should rather vigorously propagate to feed as many children as possible exclusively with breast-milk over a period of 4 to 6 months.

  17. 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.

  18. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-09-01

    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.

  20. 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.

  1. 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.

  2. 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

  3. White mould of common bean incited by Sclerotinia sclerotiorum Lib. de Bary in Egypt.

    PubMed

    Amer, M A; Abou-el-Seoud, I; Rasmy, M R; Khater, Manar M

    2009-01-01

    White mould, caused by Sclerotinia sclerotiorum (Lib.) de Bary, is a destructive yield-limiting disease of common bean (Phaseolus vulgaris L.) in Egypt. Forty eight isolate of S. sclerotiorum were isolated from diseased bean tissues taken from 9 geographical regions (Al-Behaira, Alexandria and Assiut governorates) during winter season in 2008. The pathogenicity studies showed that the tested bean cultivars (Bronco, Contender, Giza 6 and Nebraska) varied in disease incidence. Contender bean cultivar was more resistant than other cultivars. Whereas, the more virulent isolates were S5 and S6. Histology investigation of seedlings bean hypocotyls inoculated with S. sclerotiorum after 24, 48, 72 and 96 hours after inoculation indicated that penetration of bean seedlings occurred, during the first 48 hours after inoculation, through the epidermis and the outer layer of the cortex. 72 hours after inoculation, damage extended deeper into the cortical cells. Infection took place inter-and interacellularly after 96 hours more damage occurred. In addition, the invasion of the fungal hyphae through the cortical cells occurred both inter-, and intracellularly. Moreover, the observed of electron microscope both transmission and scanning investigations concluded that penetrating hyphae progressed through bean seedlings tissues leading to complete destruction of epidermis, fully colonization and death of cortical cells, partial invasion of vascular tissues. However, presence of the fungal structures in pith cells was observed.

  4. Investigation of molecular and elemental species dynamics in NTO, TNT, and ANTA using femtosecond LIBS technique

    NASA Astrophysics Data System (ADS)

    Nageswara Rao, E.; Sunku, Sreedhar; Tewari, Surya P.; Manoj Kumar, G.; Venugopal Rao, S.

    2013-05-01

    We present our initial experimental results from the LIBS studies of pyrazole, 1-nitropyrazole, 3-nitropyrazole, 3,4- dinitropyrazole and 1-methyl- 3,4,5 trinitro pyrazole recorded with femtosecond pulses and performed in argon atmosphere. CN molecular bands in three different spectral regions of 357 nm-360 nm, 384 nm-389 nm and 414 nm -423 nm, C2 swan bands near 460 nm-475 nm, 510 nm- 520 nm and 550 nm-565 nm were observed. The C peak at 247.82 nm, H peak at 656.2 nm have also been observed along with several peaks of O and N. CN/C2, CN/C, C2/C and C2/N ratios were measured from the average of 25 spectra obtained in argon. The effect of number of nitro groups on the atomic and molecular emission has been evaluated. A gate delay of 100 ns and a gate width of 800 ns were used for collecting the spectra.

  5. Fabrication of Si negative electrodes for Li-ion batteries (LIBs) using cross-linked polymer binders

    PubMed Central

    Jang, Suk-Yong; Han, Sien-Ho

    2016-01-01

    Currently, Si as an active material for LIBs has been attracting much attention due to its high theoretical specific capacity (3572 mAh g−1). However, a disadvantage when using a Si negative electrode for LIBs is the abrupt drop of its capabilities during the cycling process. Therefore, there have been a few studies of polymers such as poly(vinylidene fluoride) (PVdF), carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR) and polyacrylic acid (PAA) given that the robust structure of a polymeric binder to LIBs anodes is a promising means by which to enhance the performance of high-capacity anodes. These studies essentially focused mainly on modifying of the linear-polymer component or on copolymers dissolved in solvents. Cross-linking polymers as a binder may be preferred due to their good scratch resistance, excellent chemical resistance and high levels of adhesion and resilience. However, because these types of polymers (with a rigid structure and cross-linking points) are also insoluble in general organic solvents, applying these types in this capacity is virtually impossible. PMID:27991497

  6. Laser-induced breakdown spectroscopy (LIBS) of a high-pressure CO2-water mixture: application to carbon sequestration.

    PubMed

    Goueguel, Christian; McIntyre, Dustin L; Singh, Jagdish P; Jain, Jinesh; Karamalidis, Athanasios K

    2014-01-01

    Geologic carbon storage in deep saline aquifers is considered a feasible and possible approach of mitigating the problem of increasing greenhouse gas emissions. However, there are latent risks in which carbon dioxide (CO2) could migrate from the deep saline formations to shallower aquifers. In the event of a significant CO2 leakage to an underground source of drinking water, CO2 will dissolve in the water, thereby increasing its acidity, which could potentially enhance the solubility of various aquifer constituents, including hazardous compounds, subsequently compromising groundwater quality due to increased concentration of aqueous metals. In this paper we explore the possibility of detecting such leakage by the use of laser-induced breakdown spectroscopy (LIBS). The experiments were conducted in calcium chloride solution at three pressures of 10, 50, and 120 bar. To evaluate the direct effect of elevated CO2 on the intensity of calcium emission lines (422.67 and 393.37 nm), we also performed experiments with pure nitrogen (N2) gas, offering large water solubility contrast. We found that when performed in presence of CO2, LIBS showed only a modest decrease in Ca emission intensity from 10 to 120 bar compared to N2. These results indicate that LIBS is a viable tool for measuring brine/water contents in high-pressure CO2 environment and can be applied for monitoring CO2 leakage and displaced brine migration.

  7. Fabrication of Si negative electrodes for Li-ion batteries (LIBs) using cross-linked polymer binders

    NASA Astrophysics Data System (ADS)

    Jang, Suk-Yong; Han, Sien-Ho

    2016-12-01

    Currently, Si as an active material for LIBs has been attracting much attention due to its high theoretical specific capacity (3572 mAh g‑1). However, a disadvantage when using a Si negative electrode for LIBs is the abrupt drop of its capabilities during the cycling process. Therefore, there have been a few studies of polymers such as poly(vinylidene fluoride) (PVdF), carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR) and polyacrylic acid (PAA) given that the robust structure of a polymeric binder to LIBs anodes is a promising means by which to enhance the performance of high-capacity anodes. These studies essentially focused mainly on modifying of the linear-polymer component or on copolymers dissolved in solvents. Cross-linking polymers as a binder may be preferred due to their good scratch resistance, excellent chemical resistance and high levels of adhesion and resilience. However, because these types of polymers (with a rigid structure and cross-linking points) are also insoluble in general organic solvents, applying these types in this capacity is virtually impossible.

  8. Feeding tube - infants

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007235.htm Feeding tube - infants To use the sharing features on this page, please enable JavaScript. A feeding tube is a small, soft, plastic tube placed ...

  9. Breastfeeding vs. Formula Feeding

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old 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 ...

  10. Direct measurements of sample heating by a laser-induced air plasma in pre-ablation spark dual-pulse laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Register, Janna; Scaffidi, Jonathan; Angel, S Michael

    2012-08-01

    Direct measurements of temperature changes were made using small thermocouples (TC), placed near a laser-induced air plasma. Temperature changes up to ~500 °C were observed. From the measured temperature changes, estimates were made of the amount of heat absorbed per unit area. This allowed calculations to be made of the surface temperature, as a function of time, of a sample heated by the air plasma that is generated during orthogonal pre-ablation spark dual-pulse (DP) LIBS measurements. In separate experiments, single-pulse (SP) LIBS emission and sample ablation rate measurements were performed on nickel at sample temperatures ranging from room temperature to the maximum surface temperature that was calculated using the TC measurement results (500 °C). A small, but real sample temperature-dependent increase in both SP LIBS emission and the rate of sample ablation was found for nickel samples heated up to 500 °C. Comparison of DP LIBS emission enhancement values for bulk nickel samples at room temperature versus the enhanced SP LIBS emission and sample ablation rates observed as a function of increasing sample temperature suggests that sample heating by the laser-induced air plasma plays only a minor role in DP LIBS emission enhancement.

  11. 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.

  12. 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.

  13. Adding and Deleting Images

    EPA Pesticide Factsheets

    Images are added via the Drupal WebCMS Editor. Once an image is uploaded onto a page, it is available via the Library and your files. You can edit the metadata, delete the image permanently, and/or replace images on the Files tab.

  14. 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…

  15. Feeding Young Children.

    ERIC Educational Resources Information Center

    Poulton, Suzanne; Sexton, David

    1996-01-01

    Presents a digest of basic developmental information about children's feeding skills and behaviors, and gives general feeding recommendations. Also addresses requirements for feeding children with developmental disabilities and chronic medical conditions for which adapted environments or monitored nutrient intake may be necessary. (ET)

  16. Nasogastric feeding tube

    MedlinePlus

    Feeding - nasogastric tube; NG tube; Bolus feeding; Continuous pump feeding; Gavage tube ... If your child has an NG tube, try to keep your child from touching or pulling on the tube. After your nurse teaches you how to flush the tube ...

  17. ADS in a Nutshell

    NASA Astrophysics Data System (ADS)

    Demleitner, M.; Eichhorn, G.; Grant, C. S.; Accomazzi, A.; Murray, S. S.; Kurtz, M. J.

    1999-05-01

    The bibliographic databases maintained by the NASA Astrophysics Data System are updated approximately biweekly with records gathered from over 125 sources all over the world. Data are either sent to us electronically, retrieved by our staff via semi-automated procedures, or entered in our databases through supervised OCR procedures. PERL scripts are run on the data to convert them from their incoming format to our standard format so that they can be added to the master database at SAO. Once new data has been added, separate index files are created for authors, objects, title words, and text word, allowing these fields to be searched for individually or in combination with each other. During the indexing procedure, discipline-specific knowledge is taken into account through the use of rule-based procedures performing string normalization, context-sensitive word translation, and synonym and stop word replacement. Once the master text and index files have been updated at SAO, an automated procedure mirrors the changes in the database to the ADS mirror site via a secure network connection. The use of a public domain software tool called rsync allows incremental updating of the database files, with significant savings in the amount of data being transferred. In the past year, the ADS Abstract Service databases have grown by approximately 30%, including 50% growth in Physics, 25% growth in Astronomy and 10% growth in the Instrumentation datasets. The ADS Abstract Service now contains over 1.4 million abstracts (475K in Astronomy, 430K in Physics, 510K in Instrumentation, and 3K in Preprints), 175,000 journal abstracts, and 115,000 full text articles. In addition, we provide links to over 40,000 electronic HTML articles at other sites, 20,000 PDF articles, and 10,000 postscript articles, as well as many links to other external data sources.

  18. 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.

  19. 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.

  20. Effect of intermittent feeding, structural components and phytase on performance and behaviour of broiler chickens.

    PubMed

    Svihus, B; Lund, V B; Borjgen, B; Bedford, M R; Bakken, M

    2013-01-01

    1. Two experiments were conducted to study the effect of intermittent feeding on performance and the efficacy of an exogenous phytase, and to assess whether intermittent feeding changed the activity pattern of broiler chickens. 2. Broiler chickens were given, either ad libitum or intermittently, a phosphorus deficient pelleted diet containing either coarsely or finely ground oat hulls and either no enzyme or a phytase added from 10 d of age, in a 2 × 2 × 2 factorial arrangement. Ad libitum feeding consisted of continuous access to feed in a room with 18 h of light and 6 h of complete darkness, whereas birds on intermittent feeding had restricted access to feed from 7 d of age, with 4 1-h feeding bouts/d and one 2-h feeding bout/d from d 14. 3. Performance, characteristics of the anterior digestive tract and phosphorus retention were assessed in experiment 1, while in experiment 2, birds were observed during 4-h periods to quantify different behaviours. 4. Intermittent feeding and phytase improved performance, but intermittent feeding did not improve the efficacy of the enzyme added. Ad libitum fed broiler chickens ate and drank on average twice per hour, and spent close to three-quarters of their time resting. Apart from an increased standing and feed searching activity for intermittently fed birds compared to ad libitum fed birds during the last hour before feed was presented, no differences in activity was detected. 5. It was concluded that broiler chickens quickly adapt to intermittent feeding without reduction in final body weight and with improvements in feed efficiency, but without improving the efficacy of dietary phytase. Only small changes occur in the behaviour of intermittently fed birds compared to ad libitum fed birds.

  1. Optimization of the spectral data processing in a LIBS simultaneous elemental analysis system

    NASA Astrophysics Data System (ADS)

    Body, D.; Chadwick, B. L.

    2001-06-01

    An instrumentation variation on laser-induced breakdown spectroscopy (LIBS) is described that allows simultaneous determination of all detectable elements using a multiple spectrograph and synchronized, multiple CCD spectral acquisition system. The system is particularly suited to the rapid analysis of heterogeneous materials such as coal and mineral ores. For the analysis of a heterogeneous material the acquisition cycle typically stores 1000 spectra for subsequent filtering and analysis. The incorporation of an effective data analysis methodology has been critical in achieving both accurate and reproducible results in the analysis of powders with the technology. Using naturally occurring gypsum as the optimization matrix, various data analysis techniques have been investigated including: using pulse-to-pulse internal standardisation; data filtering; and spectral deconvolution. The incorporation of normalization of the elemental emission to the total plasma emission intensity has been found to yield the single biggest improvement in accuracy and precision. Spectral deconvolution has been found to yield further improvement and is particularly relevant to the analysis of complex materials such as black coal. The use of pulse-to-pulse intensity normalization has the further benefit of extending the period between instrument recalibration, thus enhancing the ease of use of the device. The benefit of the optimized data analysis methodology is revealed in the determination of eight elemental components of gypsum (Na, Ca, Mg, Fe, Al, Si, Ti and K) where a typical absolute analysis accuracy of ±10% is obtained. These results compare favourably to analysis by conventional techniques for these materials. The analysis accuracy and repeatability is further demonstrated by the determination of the concentrations of these elements in a black coal sample.

  2. The impact of chronic bupropion on plasma cotinine and on the subjective effects of ad lib smoking: a randomized controlled trial in unmotivated smokers.

    PubMed

    Hussain, Sarwar; Zawertailo, Laurie; Busto, Usoa; Zack, Martin; Farvolden, Peter; Selby, Peter

    2010-02-01

    Bupropion is an efficacious non-nicotine medication for smoking cessation; however, its cessation-mediating mechanism is unclear. This randomized, placebo-controlled trial examined the effect of bupropion SR (300 mg/day for 6 weeks) on plasma cotinine and on the subjective effects of smoking in 24 current daily smokers who were not trying to quit or reduce smoking. Subjective effects of smoking, as well as cue-elicited responses were assessed at bi-weekly experimental sessions using validated scales. Several indices of cigarette consumption were measured. Plasma cotinine decreased from 280 (+/-133) microg/l at baseline to 205 (+/-108) microg/l at end of treatment in the bupropion group (p=0.036), but no significant change was found in the placebo group. Daily cigarette count and puff topography did not significantly change in either group. In contrast to placebo, bupropion increased post-smoking satiety (p=0.045). Both groups reported higher craving (p=0.025) and withdrawal (p=0.014) after exposure to smoking-related pictures, compared to neutral pictures. This biased reactivity was not significantly affected by treatment condition (p>0.1). Therefore, bupropion does not appear to impact the smokers' response to conditioned smoking-related cues but influences the unconditioned subjective effects of smoking in unmotivated smokers. This study is among the first to systematically investigate the effect of chronic bupropion administration, free from the confounding effect of the smoker's motivation to quit smoking.

  3. SOD isoforms play no role in lifespan in ad lib or dietary restricted conditions, but mutational inactivation of SOD-1 reduces life extension by cold.

    PubMed

    Yen, Kelvin; Patel, Harshil B; Lublin, Alex L; Mobbs, Charles V

    2009-03-01

    The free radical theory of aging is one of the most prominent theories of aging and senescence, but has yet to be definitively proven. If free radicals are the cause of senescence, then the cellular anti-oxidant system should play a large role in lifespan determination. Because superoxide dismutase (SOD) plays a central role in detoxifying superoxide radicals, we have examined the effects of mutational inactivation of each isoform of sod on normal lifespan and lifespan extension by dietary restriction (DR) or cold-/hypothermic-induced longevity (CHIL). We find no significant decrease in lifespan for control worms or worms undergoing DR when sod isoforms are knocked-out even though sod mutational inactivation produces hypersensitivity to paraquat. In contrast, sod-1 inactivation significantly reduces lifespan extension by CHIL, suggesting that CHIL requires a specific genetic program beyond simple reduction in metabolic rate. Furthermore, CHIL paradoxically increases lifespan while reducing resistance to oxidative stress, further disassociating oxidative stress resistance and lifespan.

  4. Novel Estimation of the Humification Degree of Soil Organic Matter by Laser-Induced Breakdown Spectroscopy (LIBS) Compared to Laser-Induced Fluorescence Spectroscopy (LIFS)

    NASA Astrophysics Data System (ADS)

    Ferreira, Edilene; Ferreira, Ednaldo; Villas-Boas, Paulino; Senesi, Giorgio; Carvalho, Camila; Romano, Renan; Martin-Neto, Ladislau; Milori, Debora

    2014-05-01

    Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SOM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration in soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of Laser-Induced Breakdown Spectroscopy (LIBS) to estimate the HD of SOM was evaluated for the first time. In a LIBS experiment a high-energy laser pulse irradiates the sample and the energy absorbed by the sample causes a local heating of the material that results in its evaporation or sublimation. The high temperature of the ablated material generates a small plasma plume and, as a result of the plasma temperature, the ablated material breaks down into excited atomic and ionic species. During the plasma cooling, the excited species return to their lower energy state emitting electromagnetic radiation at characteristic wavelengths. In a LIBS spectrum the measurement of the characteristic emission wavelengths provides qualitative information about the elemental composition of the sample, whereas the intensities of the signals can be used for quantitative determinations. The LIBS potential for the analysis of organic compounds has been explored recently by using the emission lines of elements that are commonly present in organic compounds, such as the predominant C, H, P, O and N. LIBS elemental emissions were correlated to fluorescence emissions determined by Laser-Induced Fluorescence Spectroscopy (LIFS), which was considered as the reference technique. The HD of SOM determined by LIBS showed a strong correlation to that

  5. LiB12PC, the first boron-rich metal boride with phosphorus--synthesis, crystal structure, hardness, spectroscopic investigations.

    PubMed

    Vojteer, Natascha; Sagawe, Vanessa; Stauffer, Julia; Schroeder, Melanie; Hillebrecht, Harald

    2011-03-07

    We present synthesis, crystal structure, hardness, and IR/Raman and UV/Vis spectra of a new compound with the mean composition LiB(12)PC. Transparent single crystals were synthesised from Ga, Li, B, red phosphorus and C at 1500 °C in boron nitride crucibles welded in Ta ampoules. Depending on the type of boron used for the synthesis we obtained colourless, brown and red single crystals with slightly different P/C ratios. Colourless LiB(12)PC crystallizes orthorhombic in the space group Imma (No. 74) with a=10.188(2) Å, b=5.7689(11) Å, c=8.127(2) Å and Z=4. Brown LiB(12)P(0.89)C(1.11) is very similar, but with a lower P content. Red single crystals of LiB(12)P(1.13)C(0.87) have a larger unit cell with a=10.4097(18) Å, b=5.9029(7) Å, c=8.2044(12) Å. EDX measurements confirm that the red crystals contain more phosphorus than the other ones. The crystal structure is characterized by a covalent network of B(12) icosahedra connected by exohedral B-B bonds and P-P, P-C or C-C units. Li atoms are located in interstitials. The structure is closely related to MgB(7), LiB(13)C(2) and ScB(13)C. LiB(12)PC fulfils the electron counting rules of Wade and also Longuet-Higgins. Measurements of Vickers micro-hardness (H(V)=27 GPa) revealed that LiB(12)PC is a hard material. The optical band gaps obtained from UV/Vis spectra match the colours of the crystals. Furthermore we report on the IR and Raman spectra.

  6. Dual-frequency feed system for 26-meter antenna conversion

    NASA Technical Reports Server (NTRS)

    Hartop, R. W.

    1977-01-01

    New cassegrain feed cone assemblies were designed as part of the upgrade of three 26-meter diameter antennas to 34-meter diameter with improved performance. The new dual-frequency feed cone (SXD) will provide both S- and X-band feed systems and traveling wave masers, with a reflex reflector system to permit simultaneous operation analogous to the 64-meter antennas. Tasks involved in adding the X-band receiving capability and improving the S-band feed performance in support of Voyager and later missions described in.

  7. 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.

  8. Fiber Optic Feed

    DTIC Science & Technology

    1990-11-06

    Naval Research Laboratory IIK Washington, DC,20375 5000 NRL Memorandum Report 6741 0 N Fiber Optic Feed DENZIL STILWELL, MARK PARENT AND LEw GOLDBERG...SUBTITLE S. FUNDING NUMBERS Fiber Optic Feed 53-0611-A0 6. AUTHOR(S) P. D. Stilwell, M. G. Parent, L. Goldberg 7. PERFORMING ORGANIZATION NAME(S) AND...DISTRIBUTION CODE Approved for public release; distribution unlimited. 13. ABSTRACT (Maximum 200 words) This report details a Fiber Optic Feeding

  9. Xenon Feed System Progress

    DTIC Science & Technology

    2006-01-01

    From - To) 13-06-2006 Technical Paper 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER F04611-00-C-0055 Xenon Feed System Progress (Preprint) 5b. GRANT...propulsion xenon feed system for a flight technology demonstration program. Major accomplishments include: 1) Utilization of the Moog...successfully fed xenon to a 200 watt Hall Effect Thruster in a Technology Demonstration Program. The feed system has demonstrated throttling of xenon

  10. FEED FORWARD EQUATIONS.

    DTIC Science & Technology

    and feed forward stabilization) have been implemented. An on-mount gyro system consists of gyroscopes mounted on the radar antenna which sense...antenna motion and send compensating signals back to the antenna servo mechanism. Feed forward stabilization consists of determining antenna angular rates...caused by ships attitude changes, as measured by a stable platform (such as SINS), and feeding compensating signals back to the antenna servo

  11. 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.

  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. 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.

  14. Effect of sodium chloride concentration on elemental analysis of brines by laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Goueguel, Christian; Singh, Jagdish P; McIntyre, Dustin L; Jain, Jinesh; Karamalidis, Athanasios K

    2014-01-01

    Leakage of injected carbon dioxide (CO2) or resident fluids, such as brine, is a major concern associated with the injection of large volumes of CO2 into deep saline formations. Migration of brine could contaminate drinking water resources by increasing their salinity or endanger vegetation and animal life as well as human health. The main objective of this study was to investigate the effect of sodium chloride (NaCl) concentration on the detection of calcium and potassium in brine samples using laser-induced breakdown spectroscopy (LIBS). The ultimate goals were to determine the suitability of the LIBS technique for in situ measurements of metal ion concentrations in NaCl-rich solution and to develop a chemical sensor that can provide the early detection of brine intrusion into formations used for domestic or agricultural water production. Several brine samples of NaCl-CaCl2 and NaCl-KCl were prepared at NaCl concentrations between 0.0 and 3.0 M. The effect of NaCl concentration on the signal-to-background ratio (SBR) and signal-to-noise ratio (SNR) for calcium (422.67 nm) and potassium (769.49 nm) emission lines was evaluated. Results show that, for a delay time of 300 ns and a gate width of 3 μs, the presence of and changes in NaCl concentration significantly affect the SBR and SNR for both emission lines. An increase in NaCl concentration from 0.0 to 3.0 M produced an increase in the SNR, whereas the SBR dropped continuously. The detection limits obtained for both elements were in the milligrams per liter range, suggesting that a NaCl-rich solution does not severely limit the ability of LIBS to detect trace amount of metal ions.

  15. 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.

  16. 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.

  17. 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

  18. Effects of oils on feed mildew and quality.

    PubMed

    Liu, Jie; Qi, Ming; Huang, Yakuan; Guo, Jiao; Zhang, Jiacai; Li, Chong; Zhang, Niya; Sun, Lvhui; Qi, Desheng

    2016-11-27

    This study was performed to determine the effects of oils on feed mildew and feed quality. Under different moisture content conditions (10%, 13% and 16%), the basal feeds were supplemented with 4%, 6%, 8%, 10% and 12% soybean oil. In addition, at different moisture content levels (10%, 13% and 16%), the basal feed was supplemented with 12% of various types of oil (soybean, peanut, corn and fish). Subsequently, a mixed mold spore suspension was added. The feed samples were incubated at 28°C, and the total mold, water activity (Aw), moisture, acid value, crude protein (CP), crude lipid (CL), crude ash (CA) and nitrogen-free extract (NFE) levels were determined at 15, 30, 45 and 60 days. The results showed no significant variations in the feed moisture, CP, CL, CA and NEF contents. However, the acid value gradually increased in the feed samples with an extended incubation time and increasing initial moisture. The feed moisture content was a critical factor controlling feed mildew, and high levels of oil supplementation caused an elevated Aw. Additionally, peanut oil promoted mold growth in feed. These results provide a reference for the production and scientific management of formulated feed.

  19. A matrix effect and accuracy evaluation for the determination of elements in milk powder LIBS and laser ablation/ICP-OES spectrometry.

    PubMed

    Gilon, N; El-Haddad, J; Stankova, A; Lei, W; Ma, Q; Motto-Ros, V; Yu, J

    2011-11-01

    Laser ablation coupled to inductively coupled plasma optical emission spectrometry (LA-ICP-OES) and laser-induced breakdown spectroscopy (LIBS) were investigated for the determination of Ca, Mg, Zn and Na in milk samples. The accuracy of both methods was evaluated by comparison of the concentration found using LA-ICP-OES and LIBS with classical wet digestion associated with ICP-OES determination. The results were not fully acceptable, with biases from less than 1% to more than 60%. Matrix effects were also investigated. The sample matrix can influence the temperature, electron number density (n (e)) and other excitation characteristics in the ICP. These ICP characteristics were studied and evaluated during ablation of eight milk samples. Differences in n (e) (from 8.9 to 13.8 × 10(14) cm(-3)) and rotational temperature (ranging from 3,400 to 4,400 K) occurred with no correlation with trueness. LIBS results obtained after classical external calibration procedure gave degraded accuracy, indicating a strong matrix effect. The LIBS measurements clearly showed that the major problem in LA-ICP was related to the ablation process and that LIBS spectroscopy is an excellent diagnostic tool for LA-ICP techniques.

  20. Photoelectron spectroscopy and ab initio study of the doubly antiaromatic B(6) (2-) dianion in the LiB(6) (-) cluster.

    PubMed

    Alexandrova, Anastassia N; Boldyrev, Alexander I; Zhai, Hua-Jin; Wang, Lai-Sheng

    2005-02-01

    A metal-boron mixed cluster LiB(6) (-) was produced and characterized by photoelectron spectroscopy and ab initio calculations. A number of electronic transitions were observed and used to compare with theoretical calculations. An extensive search for the global minimum of LiB(6) (-) was carried out via an ab initio genetic algorithm technique. The pyramidal C(2v) ((1)A(1)) molecule was found to be the most stable at all levels of theory. The nearest low-lying isomer was found to be a triplet C(2) ((3)B) structure, 9.2 kcal/mol higher in energy. Comparison of calculated detachment transitions from LiB(6) (-) and the experimental photoelectron spectra confirmed the C(2v) pyramidal global minimum structure. Natural population calculation revealed that LiB(6) (-) is a charge-transfer complex, Li(+)B(6) (2-), in which Li(+) and B(6) (2-) interact in a primarily ionic manner. Analyses of the molecular orbitals and chemical bonding of B(6) (2-) showed that the planar cluster is twofold (pi- and sigma-) antiaromatic, which can be viewed as the fusion of two aromatic B(3) (-) units.

  1. 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

  2. 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.

  3. 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.

  4. 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…

  5. 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...

  6. 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…

  7. 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...

  8. 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…

  9. Sensory suppression during feeding

    PubMed Central

    Foo, H.; Mason, Peggy

    2005-01-01

    Feeding is essential for survival, whereas withdrawal and escape reactions are fundamentally protective. These critical behaviors can compete for an animal's resources when an acutely painful stimulus affects the animal during feeding. One solution to the feeding-withdrawal conflict is to optimize feeding by suppressing pain. We examined whether rats continue to feed when challenged with a painful stimulus. During feeding, motor withdrawal responses to noxious paw heat either did not occur or were greatly delayed. To investigate the neural basis of sensory suppression accompanying feeding, we recorded from brainstem pain-modulatory neurons involved in the descending control of pain transmission. During feeding, pain-facilitatory ON cells were inhibited and pain-inhibitory OFF cells were excited. When a nonpainful somatosensory stimulus preactivated ON cells and preinhibited OFF cells, rats interrupted eating to react to painful stimuli. Inactivation of the brainstem region containing ON and OFF cells also blocked pain suppression during eating, demonstrating that brainstem pain-modulatory neurons suppress motor reactions to external stimulation during homeostatic behaviors. PMID:16275919

  10. 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.

  11. Effect of early feed restriction on reproductive performance in Japanese quail (Coturnix coturnix japonica).

    PubMed

    Hassan, S M; Mady, M E; Cartwright, A L; Sabri, H M; Mobarak, M S

    2003-07-01

    Reproductive performance of quail (Coturnix coturnix japonica) was evaluated following feed restriction (100, 85, and 70% of ad libitum) between 2 to 5 wk of age with three replicates of 12, 2-wk-old chicks per replicate. Body weight, feed conversion, and leucocyte distribution were measured during feed restriction. After experimental feed treatment, BW, age at first egg, egg production, fertility, hatchability, and embryonic mortality were evaluated from five replicates of two females and one male per treatment. Feed-restricted female chicks had lower BW from 3 to 5 wk of age, but male weights were depressed only during the most severe restriction at 4 and 5 wk. No treatment differences were observed among BW within a sex from 6 to 13 wk. Body weights at first egg were significantly heavier for females fed 70% ad libitum than for birds on other treatments. Fertility, age at first egg, feed conversion, egg production, and egg weight were unaffected by feed restriction. Although hatchability was unaffected by feed restriction, percentage of late dead and total dead embryos were significantly reduced in eggs from restricted quail. Thirty quail fed 70% of ad libitum control intake had significantly increased egg specific gravity. Feed restriction increased the percentage of heterophils and basophils and the heterophil/lymphocyte ratio, whereas the percentage of lymphocytes and eosinophils decreased. Feed can be restricted to 85 or 70% of ad libitum feed intake from 2 to 5 wk of age without detrimentally affecting reproductive parameters between 6 to 13 wk of age.

  12. Supersymmetry of AdS and flat IIB backgrounds

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

    We present a systematic description of all warped AdS n × w M 10- n and IIB backgrounds and identify the a priori number of supersymmetries N preserved by these solutions. In particular, we find that the AdS n backgrounds preserve for n ≤ 4 and for 4 < n ≤ 6 supersymmetries and for suitably restricted. In addition under some assumptions required for the applicability of the maximum principle, we demonstrate that the Killing spinors of AdS n backgrounds can be identified with the zero modes of Dirac-like operators on M 10- n establishing a new class of Lichnerowicz type theorems. Furthermore, we adapt some of these results to backgrounds with fluxes by taking the AdS radius to infinity. We find that these backgrounds preserve for 2 < n ≤ 4 and for 4 < n ≤ 7 supersymmetries. We also demonstrate that the Killing spinors of AdS n × w M 10- n do not factorize into Killing spinors on AdS n and Killing spinors on M 10- n .

  13. [Value-Added--Adding Economic Value in the Food Industry].

    ERIC Educational Resources Information Center

    Welch, Mary A., Ed.

    1989-01-01

    This booklet focuses on the economic concept of "value added" to goods and services. A student activity worksheet illustrates how the steps involved in processing food are examples of the concept of value added. The booklet further links food processing to the idea of value added to the Gross National Product (GNP). Discussion questions,…

  14. Mechanisms of Feeding Deterrence by Ziziphins.

    DTIC Science & Technology

    2014-09-26

    AD-A157 469 MECHRNISMS OF FEEDING DETERRENCE BY ZIZIPHINS(U) / CORNELL UNIV ITHACA NY 8 P HRLPERN 30 NAY 65 SIID 7- BHP -CU-RRO RRO-i8882.2-LS DRAA2...OOWNGRADING SCHEDULE unlimited. 4. PERFORMING ORGANIZATION REPORT NUMBERiS) 5. MONITORING ORGANIZATION REPORT NUMBERtS) 7- BHP -CU-ARO IJ,’tt . -4S 6a. NAME OF

  15. 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.

  16. Insight to UV-induced formation of laser damage on LiB(3)O(5) optical surfaces during long-term sum-frequency generation.

    PubMed

    Möller, S; Andresen, A; Merschjann, C; Zimmermann, B; Prinz, M; Imlau, M

    2007-06-11

    Microscopic investigations of UV-induced formation of laser damage on LiB(3)O(5) optical surfaces during long-term sum-frequency generation (SFG) uncovers a significant growth of a SiO(2)-amorphous layer spatially limited to the illuminated area. The layer gives rise to a catastrophic break-down of the LiB(3)O(5)-output surface upon long-term laser operation even at intensities far below the laser-induced damage threshold. The interaction of UV laser light, LiB(3)O(5) surface and foreign atoms in the ambient atmosphere is discussed in the frame of a two-step process for surface-damage formation.

  17. Suthi feeding: an experience.

    PubMed

    Gupta, B D; Jain, P; Mandowara, S L

    1995-06-01

    In cases in which expressed breast milk is given or breast feeding cannot be done at all, a suitable alternative to breast feeding is still in question. Bottle feeding poses many hazards. Spoon and bowl have been proposed as a reasonable alternative since users can achieve better cleanliness. Yet it is impractical for staff in health facility nurseries to feed every newborn with the spoon and bowl method since it requires so much time. On average, they need to provide oral feeds to at least 10 babies a day. In India, maternal grandparents present the family of a newborn with the traditional Sindhi silver or stainless steel utensil to provide the infant drinking water. It is called Suthi. It holds either 10 or 20 cc, making it easier to quantify the amount of milk/feed. It has a long semicircular beak and curved rounded margins. Advantages of the Suthi over other alternative feeding methods include: it is a shallow container with a broad upper surface, allowing the user to clean it thoroughly and easily; its narrow beak can go directly into the mouth of the newborn, particularly premature infants and low birth weight infants, with relative ease, reducing the likelihood of spilling milk, and the Suthi feeding procedure is less messy and faster (7-10 vs. 15-20 minutes for spoon) than other procedures. The Suthi method allows nursery staff to spend less time per feed for 8-10 babies (minimum time needed, 1 vs. 3 hours). It can also be used at home. Its use will reduce the likelihood of aspiration since it cannot be used lying down. Since it is a traditional container, the community will accept Suthi. When breast feeding is not possible, the Suthi should be used.

  18. 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.

  19. 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.

  20. 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.

  1. Laser-induced breakdown spectroscopy (LIBS) technique for the determination of the chemical composition of complex inorganic materials

    NASA Astrophysics Data System (ADS)

    Łazarek, Łukasz; Antończak, Arkadiusz J.; Wójcik, Michał R.; Kozioł, Paweł E.; Stepak, Bogusz; Abramski, Krzysztof M.

    2014-08-01

    Laser-induced breakdown spectroscopy (LIBS) is a fast, fully optical method, that needs little or no sample preparation. In this technique qualitative and quantitative analysis is based on comparison. The determination of composition is generally based on the construction of a calibration curve namely the LIBS signal versus the concentration of the analyte. Typically, to calibrate the system, certified reference materials with known elemental composition are used. Nevertheless, such samples due to differences in the overall composition with respect to the used complex inorganic materials can influence significantly on the accuracy. There are also some intermediate factors which can cause imprecision in measurements, such as optical absorption, surface structure, thermal conductivity etc. This paper presents the calibration procedure performed with especially prepared pellets from the tested materials, which composition was previously defined. We also proposed methods of post-processing which allowed for mitigation of the matrix effects and for a reliable and accurate analysis. This technique was implemented for determination of trace elements in industrial copper concentrates standardized by conventional atomic absorption spectroscopy with a flame atomizer. A series of copper flotation concentrate samples was analyzed for contents of three elements, that is silver, cobalt and vanadium. It has been shown that the described technique can be used to qualitative and quantitative analyses of complex inorganic materials, such as copper flotation concentrates.

  2. Challenges in measuring feed efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The term feed efficiency is vague, and is defined differently by people. Historically, feed efficiency has been defined as the feed:gain (F:G) ratio or the inverse (G:F). Indexes have been developed to rank animals for feed efficiency. These indexes include residual feed intake (RFI) and residual...

  3. Care and Feeding of Frogs

    NASA Astrophysics Data System (ADS)

    Pan, Margaret; Chiang, Eugene

    2012-01-01

    "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, "Blériot," appear consistent with a sinusoid of period ~4 years. Pan & 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 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 delay exceeds the frog libration period P lib, and if damping from Lindblad torques balances driving from co-orbital torques. If t delay Lt P lib, then the libration amplitude damps to zero. In the case of Blériot, the frog resonance model can reproduce the observed libration period P lib ~= 4 yr. However, our simple feedback prescription suggests that Blériot's t delay ~ 0.01P 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.

  4. AdS3 Solutions of IIB Supergravity

    SciTech Connect

    Kim, Nakwoo

    2005-12-02

    We consider pure D3-brane configurations of IIB string theory which lead to supergravity solutions containing an AdS3 factor. They can provide new examples of AdS3/CFT2 examples on D3-branes whose worldvolume is partially compactified. When the internal 7 dimensional space is non-compact, they are related to fluctuations of higher dimensional AdS/CFT duality examples, thus dual to the BPS operators of D = 4 superconformal field theories. We find that supersymmetry requires the 7 dimensional space is warped Hopf-fibration of (real) 6 dimensional Kahler manifolds.

  5. Review: Quantifying animal feeding behaviour with a focus on pigs.

    PubMed

    Maselyne, Jarissa; Saeys, Wouter; Van Nuffel, Annelies

    2015-01-01

    The study of animal feeding behaviour is of interest to understand feeding, to investigate the effect of treatments and conditions or to predict illness. This paper reviews the different steps to undertake when studying animal feeding behaviour, with illustrations for group-housed pigs. First, one must be aware of the mechanisms that control feeding and the various influences that can change feeding behaviour. Satiety is shown to largely influence free feeding (ad libitum and without an operant condition) in animals, but 'free' feeding seems a very fragile process, given the many factors that can influence feeding behaviour. Second, a measurement method must be chosen that is compatible with the goal of the research. Several measurement methods exist, which lead to different experimental set-ups and measurement data. Sensors are available for lab conditions, for research on group-housed pigs and also for on-farm use. Most of these methods result in a record of feeding visits. However, these feeding visits are often found to be clustered into meals. Thus, the third step is to choose which unit of feeding behaviour to use for analysis. Depending on the situation, either meals, feeding visits, other raw data, or a combination thereof can be suitable. Meals are more appropriate for analysing short-term feeding behaviour, but this may not be true for disease detection. Further research is therefore needed. To cluster visits into meals, an appropriate analysis method has to be selected. The last part of this paper provides a review and discussion of the existing methods for meal determination. A variety of methods exist, with the most recent methods based on the influence of satiety on feeding. More thorough validation of the recent methods, including validation from a behavioural point of view and uniformity in the applied methods is therefore necessary.

  6. Action growth for AdS black holes

    NASA Astrophysics Data System (ADS)

    Cai, Rong-Gen; Ruan, Shan-Ming; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui

    2016-09-01

    Recently a Complexity-Action (CA) duality conjecture has been proposed, which relates the quantum complexity of a holographic boundary state to the action of a Wheeler-DeWitt (WDW) patch in the anti-de Sitter (AdS) bulk. In this paper we further investigate the duality conjecture for stationary AdS black holes and derive some exact results for the growth rate of action within the Wheeler-DeWitt (WDW) patch at late time approximation, which is supposed to be dual to the growth rate of quantum complexity of holographic state. Based on the results from the general D-dimensional Reissner-Nordström (RN)-AdS black hole, rotating/charged Bañados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a universal formula for the action growth expressed in terms of some thermodynamical quantities associated with the outer and inner horizons of the AdS black holes. And we leave the conjecture unchanged that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.

  7. 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…

  8. Constructing the AdS dual of a Fermi liquid: AdS black holes with Dirac hair

    NASA Astrophysics Data System (ADS)

    Čubrović, Mihailo; Zaanen, Jan; Schalm, Koenraad

    2011-10-01

    We provide evidence that the holographic dual to a strongly coupled charged Fermi liquid has a non-zero fermion density in the bulk. We show that the pole-strength of the stable quasiparticle characterizing the Fermi surface is encoded in the AdS probability density of a single normalizable fermion wavefunction in AdS. Recalling Migdal's theorem which relates the pole strength to the Fermi-Dirac characteristic discontinuity in the number density at ω F , we conclude that the AdS dual of a Fermi liquid is described by occupied on-shell fermionic modes in AdS. Encoding the occupied levels in the total spatially averaged probability density of the fermion field directly, we show that an AdS Reissner-Nordström black holein a theory with charged fermions has a critical temperature, at which the system undergoes a first-order transition to a black hole with a non-vanishing profile for the bulk fermion field. Thermodynamics and spectral analysis support that the solution with non-zero AdS fermion-profile is the preferred ground state at low temperatures.

  9. 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.

  10. Feeding regulation in Drosophila

    PubMed Central

    Pool, Allan-Hermann; Scott, Kristin

    2014-01-01

    Neuromodulators play a key role in adjusting animal behavior based on environmental cues and internal needs. Here, we review the regulation of Drosophila feeding behavior to illustrate how neuromodulators achieve behavioral plasticity. Recent studies have made rapid progress in determining molecular and cellular mechanisms that translate the metabolic needs of the fly into changes in neuroendocrine and neuromodulatory states. These neuromodulators in turn promote or inhibit discrete feeding behavioral subprograms. This review highlights the links between physiological needs, neuromodulatory states, and feeding decisions. PMID:24937262

  11. 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.

  12. AdS-Carroll branes

    NASA Astrophysics Data System (ADS)

    Clark, T. E.; ter Veldhuis, T.

    2016-11-01

    Coset methods are used to determine the action of a co-dimension one brane (domain wall) embedded in (d + 1)-dimensional AdS space in the Carroll limit in which the speed of light goes to zero. The action is invariant under the non-linearly realized symmetries of the AdS-Carroll spacetime. The Nambu-Goldstone field exhibits a static spatial distribution for the brane with a time varying momentum density related to the brane's spatial shape as well as the AdS-C geometry. The AdS-C vector field dual theory is obtained.

  13. ADS Based on Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Pan, Weimin; Dai, Jianping

    An accelerator-driven system (ADS), which combines a particle accelerator with a subcritical core, is commonly regarded as a promising device for the transmutation of nuclear waste, as well as a potential scheme for thorium-based energy production. So far the predominant choice of the accelerator for ADS is a superconducting linear accelerator (linac). This article gives a brief overview of ADS based on linacs, including the motivation, principle, challenges and research activities around the world. The status and future plan of the Chinease ADS (C-ADS) project will be highlighted and discussed in depth as an example.

  14. AdS spacetimes from wrapped D3-branes

    NASA Astrophysics Data System (ADS)

    Gauntlett, Jerome P.; MacConamhna, Oisín A. P.

    2007-12-01

    We derive a geometrical characterization of a large class of AdS3 and AdS2 supersymmetric spacetimes in type IIB supergravity with non-vanishing five-form flux using G-structures. These are obtained as special cases of a class of supersymmetric spacetimes with an {{\\bb R}}^{1,1} or {{\\bb R}} (time) factor that are associated with D3 branes wrapping calibrated two or three cycles, respectively, in manifolds with SU(2), SU(3), SU(4) and G2 holonomy. We show how two explicit AdS solutions, previously constructed in gauged supergravity, satisfy our more general G-structure conditions. For each explicit solution, we also derive a special holonomy metric which, although singular, has an appropriate calibrated cycle. After analytic continuation, some of the classes of AdS spacetimes give rise to known classes of BPS bubble solutions with {{\\bb R}}\\times {\\it SO}(4)\\times {\\it SO}(4), {{\\bb R}}\\times {\\it SO}(4)\\times U(1) and {{\\bb R}}\\times {\\it SO}(4) symmetry. These have 1/2, 1/4 and 1/8 supersymmetry, respectively. We present a new class of 1/8 BPS geometries with {{\\bb R}}\\times {\\it SU}(2) symmetry, obtained by analytic continuation of the class of AdS spacetimes associated with D3-brane wrapped on associative three cycles.

  15. Effect of prolonged breast-feeding on risk of atopic dermatitis in early childhood.

    PubMed

    Hong, Soyoung; Choi, Won-Jun; Kwon, Ho-Jang; Cho, Yoon Hee; Yum, Hye Yung; Son, Dong Koog

    2014-01-01

    The effect of breast-feeding on the risk of developing atopic disease remains controversial. This study is an investigation of the effect of breast-feeding on current atopic dermatitis (AD) among Korean children. This cross-sectional study of children's histories of current AD and environmental factors was completed by the subjects' parents. The subjects included 10,383 children aged 0-13 years in Seoul, Korea, in 2008. The diagnostic criteria of the International Study of Asthma and Allergies in Childhood were applied in this study. Adjustments were performed for age, gender, maternal education, smoking in the household, relocation to a new house within 1 year of birth, and parental history of atopic disease. After adjustment for confounders, age and duration of maternal education were found to be inversely associated with the prevalence of AD. Among subjects aged ≤5 years, the prevalence of AD was positively associated with the duration of breast-feeding (p < 0.001). However, there was no significant association between AD and breast-feeding among children >5 years of age. Regardless of parental history of atopic diseases, breast-feeding >12 months was a significant risk factor for AD. The effect of breast-feeding differed by age group. Prolonged breast-feeding increased the risk of AD in children <5 years of age, regardless of parental history of atopic diseases.

  16. 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, ...

  17. Breastfeeding vs. Formula Feeding

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000803.htm Breastfeeding vs. Formula Feeding To use the sharing features ... best for you and your family. Benefits of Breastfeeding Breastfeeding is a wonderful way to bond with ...

  18. The effect of quantitative feed restriction on allometric growth in broilers.

    PubMed

    van der Klein, S A S; Silva, F A; Kwakkel, R P; Zuidhof, M J

    2017-01-01

    Feed restriction in broilers is aimed at preventing metabolic disorders, increasing feed efficiency, or manipulating carcass conformation. The purpose of the current study was to investigate the effects of modest graded levels feed restriction during the second and third wk of life. Mixed-sex chickens were raised in pens with 4 replications per treatment to 35 d of age. Chickens were fed ad libitum throughout the trial, or 90, 80, or 70% of expected ad libitum feed intake during the second wk of life, or 95, 90, 85, or 80% of expected ad libitum feed intake during the third wk of life. Feed intake, BW, ADG, and feed conversion ratio (FCR) were measured and weekly dissections were conducted to characterize allometric growth of the breast muscle, legs, abdominal fat pad, liver, gastro-intestinal tract (GIT), and heart. Feeding 70% of ad libitum during wk 2 and 80% during wk 3 reduced ADG during the restriction period and reduced BW at the end of the restriction period, but chickens exhibited complete compensatory growth within one wk after the restriction period. No significant effects of restriction treatment were found on BW, FCR, fat pad, empty GIT, breast muscle, heart, legs, and liver weight at d 35, but allometric growth curve for breast muscle was lower in birds fed 80 and 85% of ad libitum during wk 3, and for birds fed 70% of ad libitum in wk 2. Allometric growth curves for all body parts were different between males and females, except for the liver. Females had higher relative fat pad, breast muscle, and liver weight and a lower GIT and heart and leg weight compared with males at d 35. Feed restriction could differentially affect males and females. This study showed that feeding 70% of ad libitum in wk 2 might be beneficial to reduce fat pad, but later feed restriction in wk 3 may reduce breast muscle weight at broiler processing age.

  19. Revisiting the thermodynamic relations in AdS /CMT models

    NASA Astrophysics Data System (ADS)

    Hyun, Seungjoon; Park, Sang-A.; Yi, Sang-Heon

    2017-03-01

    Motivated by the recent unified approach to the Smarr-like relation of anti-de Sitter (AdS) planar black holes in conjunction with the quasilocal formalism on conserved charges, we revisit the quantum statistical and thermodynamic relations of hairy AdS planar black holes. By extending the previous results, we identify the hairy contribution in the bulk and show that the holographic computation can be improved so that it is consistent with the bulk computation. We argue that the first law can be retained in its universal form and that the relation between the on-shell renormalized Euclidean action and its free energy interpretation in gravity may also be undeformed even with the hairy contribution in hairy AdS black holes.

  20. Entanglement entropy for free scalar fields in AdS

    NASA Astrophysics Data System (ADS)

    Sugishita, Sotaro

    2016-09-01

    We compute entanglement entropy for free massive scalar fields in anti-de Sitter (AdS) space. The entangling surface is a minimal surface whose boundary is a sphere at the boundary of AdS. The entropy can be evaluated from the thermal free energy of the fields on a topological black hole by using the replica method. In odd-dimensional AdS, exact expressions of the Rényi entropy S n are obtained for arbitrary n. We also evaluate 1-loop corrections coming from the scalar fields to holographic entanglement entropy. Applying the results, we compute the leading difference of entanglement entropy between two holographic CFTs related by a renormalization group flow triggered by a double trace deformation. The difference is proportional to the shift of a central charge under the flow.

  1. Solutions of free higher spins in AdS

    NASA Astrophysics Data System (ADS)

    Lü, H.; Shao, Kai-Nan

    2011-11-01

    We consider free massive and massless higher integer spins in AdS backgrounds in general D dimensions. We obtain the solutions corresponding to the highest-weight state of the spin-ℓ representations of the SO (2 , D - 1) isometry groups. The solution for the spin-ℓ field is expressed recursively in terms of that for the spin- (ℓ - 1). Thus starting from the explicit spin-0, all the higher-spin solutions can be obtained. These solutions allow us to derive the generalized Breitenlohner-Freedman bound, and analyze the asymptotic falloffs. In particular, solutions with negative mass square in general have falloffs slower than those of the Schwarzschild AdS black holes in the AdS boundaries.

  2. 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

  3. Diffusion and chaos from near AdS2 horizons

    NASA Astrophysics Data System (ADS)

    Blake, Mike; Donos, Aristomenis

    2017-02-01

    We calculate the thermal diffusivity D = κ/c ρ and butterfly velocity v B in holographic models that flow to AdS2 × R d fixed points in the infra-red. We show that both these quantities are governed by the same irrelevant deformation of AdS2 and hence establish a simple relationship between them. When this deformation corresponds to a universal dilaton mode of dimension Δ = 2 then this relationship is always given by D = v B 2 /(2 πT).

  4. 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... (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....

  5. Analysis of Ti in textile stippled by TiO2 nanoparticle sol using double-pulse LIBS and ED XRF spectrometry

    NASA Astrophysics Data System (ADS)

    Pouzar, M.; Průšová, M.; Černohorský, T.; Wiener, J.; Kratochvil, T.

    2011-11-01

    Double-pulse LIBS and ED XRF usabilities for quantitative analysis of Ti in samples of cotton, wool, and viscose fabrics were compared to each other. The analyzed samples were prepared by stippling a particular fabric with TiO2 nanoparticle sol (particle size 100 nm). Both spectrometers were calibrated with the aid of the same sets of authentic fabric samples previously analyzed by ICP OES after the microwave digestion. Average values of the Ti concentration calculated from five repeated measurements of the same sample obtained by LIBS and ED XRF were comparable for all types of the tested materials (100•(CTi-LIBS/CTi-ED XRF)) ≅ 96-109%), but the precision of analysis expressed as RSD (relative standard deviation) was usually better for ED XRF (RSDLIBS from 9 to 25%, RSDED XRF from 3 to 17%). Poor RSD values of LIBS measurements were observed mainly in the case of samples with lower areal weights. Limits of detection calculated as a triple standard deviation of five repeated measurements of Ti in a sample with the low concentration of the analyte were comparable for both methods (LODLIBS = from 15 to 97, and LODED XRF = from 21 to 64, all in mg/kg).

  6. Development of an apparatus for on-line analysis of unburned carbon in fly ash using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Zhang, Lei; Ma, Weiguang; Dong, Lei; Yan, Xiaojuan; Hu, Zhiyu; Li, Zhixin; Zhang, Yongzhi; Wang, Le; Yin, Wangbao; Jia, Suotang

    2011-07-01

    The level of unburned carbon in fly ash is an important criteria for evaluating the combustion efficiencies of boilers, as well as the commercial value of the produced fly ash. In this work, an automated prototype laser-induced breakdown spectroscopy (LIBS) apparatus comprising an isokinetic sampler, a sample preparation module, and a LIBS module has been developed for possible application to power plants for on-line analysis of unburned carbon in fly ash without being affected by the type of coal burned. Emphasis is placed on the structure and operation of the LIBS apparatus, the optimum suction capacity selection, the analytical methods for estimation of the exact C line intensity, and the proper calibration model established for minimizing the matrix effects, which enable the minimization of matrix effects and obtaining more accurate compositional measurements. Good agreement has been found between the laboratory measurement results from the LIBS method and those from the traditional method. The measurement accuracy presented here for unburned carbon analysis is estimated to be 0.26%, while the average relative error is 3.81%.

  7. 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…

  8. Simple and direct method for detecting phosphorus in air at normal pressure and temperature using a combination of LIBS and LIFS techniques

    NASA Astrophysics Data System (ADS)

    Al-Jeffery, Mohammad O.; Kondou, H.; Belenkevitch, Alexander; Azzeer, Abdallah M.

    2002-05-01

    The Environmental Protection Agency (EAP) designated phosphorus as hazardous material; it is flammable and poisonous. Phosphorus attacks the respiratory system, liver, kidneys, jaw, teeth, blood, eyes, and skin. Phosphorus is an element that has a high detection limit when using laser-induced breakdown spectroscopy (LIBS) techniques. In order to improve on detection limits, laser-induced fluorescence spectroscopy (LIFS) has been proposed, as an extension to LIBS. The ultimate goal of this work is to use the combined LIBS & LIFS techniques to detect the presence of phosphorus in air and to measure its level. In order to provide 'proof-of-concept' results, the sample used for our experiment was prepared using the 'igniting' strip of a safety match box. The spectrally and temporally resolved detection of the specific atomic emission revealed analytical information about the elemental composition of the sample. A tunable Ti: sapphire laser, at the resonance wavelength of 253.4 nm, was then used to probe the plume by exciting the phosphorus element and we measured the fluorescence from the atoms at 213.62 nm and 214.91 nm. The whole experiment was carried out in a few minutes. We have thus demonstrated for the first time, to our knowledge, the use of LIBS and LIFS in air quality monitoring and in particular for phosphorus detection.

  9. 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…

  10. The influence of ns- and fs-LA plume local conditions on the performance of a combined LIBS/LA-ICP-MS sensor

    SciTech Connect

    LaHaye, Nicole L.; Phillips, Mark C.; Duffin, Andrew M.; Eiden, Gregory C.; Harilal, Sivanandan S.

    2016-01-01

    Both laser-induced breakdown spectroscopy (LIBS) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are well-established analytical techniques with their own unique advantages and disadvantages. The combination of the two analytical methods is a very promising way to overcome the challenges faced by each method individually. We made a comprehensive comparison of local plasma conditions between nanosecond (ns) and femtosecond (fs) laser ablation (LA) sources in a combined LIBS and LA-ICP-MS system. The optical emission spectra and ICP-MS signal were recorded simultaneously for both ns- and fs-LA and figures of merit of the system were analyzed. Characterization of the plasma was conducted by evaluating temperature and density of the plume under various irradiation conditions using optical emission spectroscopy, and correlations to ns- and fs-LIBS and LA-ICP-MS signal were made. The present study is very useful for providing conditions for a multimodal system as well as giving insight into how laser ablation plume parameters are related to LA-ICP-MS and LIBS results for both ns- and fs-LA.

  11. Free-running and Q:Switched LIBS measurements during the laser ablation of Prickle Pears spines

    NASA Astrophysics Data System (ADS)

    Flores, T.; Ponce, L.; Arronte, M.; de Posada, E.

    2009-05-01

    The pulse laser ablation (PLA) as a new method for spines elimination of Prickle Pear fruit is presented. The new technique works thanks to the use of the pulsed light that is absorbed in a selective way, specifically in the spines. An optical characterization of both spine and cactus cortex allows to find the most convenient pulse energy for selective absorption. By using laser-induced breakdown spectroscopy (LIBS) in Q:Switch and free-running regimes, it is possible to control the process in real time and to check the cleaning results online. The feasibility of performing the laser ablation of spines without visible damages to the substrate was proved by the optical microscopy observation.

  12. Synthesis of single-crystal low-loss LiB3O5 nanowire and its optical properties

    PubMed Central

    Qu, Guang-Yuan; Yang, Cheng-Wei; Cui, Guo-xin; Zhang, Xue-Jin; Lu, Yan-Qing

    2016-01-01

    Optical-quality single-crystal LiB3O5 (LBO) nanowires are synthesized for the first time using a sol–gel method. The LBO nanowires possess diameters ranging from 200 to 800 nm and lengths of up to 200 μm, and exhibit excellent uniformity, smooth surfaces, and good mechanical properties. A typical propagating loss of 0.038 dB/μm at 532 nm is obtained for a 620 nm-diameter nanowire. This is a decrease of one order of magnitude compared with that of a β-BaB2O4 (BBO) nanowire with similar diameter, which makes the LBO nanowire a promising candidate to construct miniaturized nonlinear photonic devices. PMID:27991549

  13. Synthesis of single-crystal low-loss LiB3O5 nanowire and its optical properties

    NASA Astrophysics Data System (ADS)

    Qu, Guang-Yuan; Yang, Cheng-Wei; Cui, Guo-Xin; Zhang, Xue-Jin; Lu, Yan-Qing

    2016-12-01

    Optical-quality single-crystal LiB3O5 (LBO) nanowires are synthesized for the first time using a sol–gel method. The LBO nanowires possess diameters ranging from 200 to 800 nm and lengths of up to 200 μm, and exhibit excellent uniformity, smooth surfaces, and good mechanical properties. A typical propagating loss of 0.038 dB/μm at 532 nm is obtained for a 620 nm-diameter nanowire. This is a decrease of one order of magnitude compared with that of a β-BaB2O4 (BBO) nanowire with similar diameter, which makes the LBO nanowire a promising candidate to construct miniaturized nonlinear photonic devices.

  14. Comparative Study of Elemental Nutrients in Organic and Conventional Vegetables Using Laser-Induced Breakdown Spectroscopy (LIBS).

    PubMed

    Bhatt, Chet R; Alfarraj, Bader; Ghany, Charles T; Yueh, Fang Y; Singh, Jagdish P

    2017-01-01

    In this study, the laser-induced breakdown spectroscopy (LIBS) technique was used to identify and compare the presence of major nutrient elements in organic and conventional vegetables. Different parts of cauliflowers and broccolis were used as working samples. Laser-induced breakdown spectra from these samples were acquired at optimum values of laser energy, gate delay, and gate width. Both univariate and multivariate analyses were performed for the comparison of these organic and conventional vegetable flowers. Principal component analysis (PCA) was taken into account for multivariate analysis while for univariate analysis, the intensity of selected atomic lines of different elements and their intensity ratio with some reference lines of organic cauliflower and broccoli samples were compared with those of conventional ones. In addition, different parts of the cauliflower and broccoli were compared in terms of intensity and intensity ratio of elemental lines.

  15. The SuperCam Remote Sensing Suite for MARS 2020: Nested and Co-Aligned LIBS, Raman, and VISIR Spectroscopies, and color micro-imaging

    NASA Astrophysics Data System (ADS)

    Fouchet, Thierry; Wiens, Roger; Maurice, Sylvestre; Johnson, Jeffrey R.; Clegg, Samuel; Sharma, Shiv; Rull, Fernando; Montmessin, Franck; Anderson, Ryan; Beyssac, Olivier; Bonal, Lydie; Deflores, Lauren; Dromart, Gilles; Fischer, William; Forni, Olivier; Gasnault, Olivier; Grotzinger, John P.; Mangold, Nicolas; Martinez-Frias, Jesus; MacLennan, Scott; McCabe, Kevin; cais, Philippe; Nelson, Tony; Angel, Stanley; Beck, Pierre; Benzerara, Karim; Bernard, Sylvain; Bousquet, Bruno; Bridges, Nathan; Cloutis, Edward; Fabre, Cécile; Grasset, Olivier; Lanza, Nina; Lasue, Jeremie; Le Mouélic, Stéphane; Leveille, Rich; Lewin, Eric; McConnochie, Timothy H.; Melikechi, Noureddine; Meslin, Pierre-Yves; Misra, Anupam; Montagnac, Gilles; Newsom, Horton; Ollila, Ann; Pinet, Patrick; Poulet, Francois; Sobron, Pablo

    2016-10-01

    As chartered by the Science Definition Team, the Mars 2020 mission addresses four primary objectives: A. Characterize the processes that formed and modified the geologic record within an astrobiologically relevant ancient environment, B. Perform astrobiologically relevant investigations to determine habitability, search for materials with biosignature presentation potential, and search for evidence of past life, C. Assemble a returnable cache of samples and D. Contribute to preparation for human exploration of Mars. The SuperCam instrument, selected for the Mars 2020 rover, as a suite of four instruments, provides nested and co-aligned remote investigations: Laser Induced Breakdown Spectroscopy (LIBS), Raman spectroscopy and time-resolved fluorescence (TRF), visible and near-infrared spectroscopy (VISIR), and high resolution color imaging (RMI). SuperCam appeals broadly to the four Mars 2020 objectives.In detail, SuperCam will perform:1. Microscale mineral identification by combining LIBS elemental and VISIR mineralogical spectroscopies, especially targeting secondary minerals2. Determine the sedimental stratigraphy through color imaging and LIBS and VISIR spectroscopy3. Search for organics and bio-signatures with LIBS and Raman spectroscopy4. Quantify the volatile content of the rocks by LIBS spectroscopy to determine the degree of aquaeous alteration5. Characterize the texture of the rocks by color imaging to determine their alteration processes6. Characterize the rocks' coatings by LIBS spectroscopy7. Characterize the soil and its potential for biosignature preservation8. Monitor the odd-oxygen atmospheric chemistry.To meet these goals SuperCam will perform LIBS spectroscopy on 0.5 mm spot up to 7-meter distance, perform Raman and time-resolved fluoresence up to 12-m distance with a 0.8 mrad angular resolution, a 100 ns time gating in the 534-850 nm spectral range, acquire VISIR spectra in the range 0.4-0.85 μm with a resolution of 0.35 nm, and in the IR range

  16. 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.

  17. 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.

  18. 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.

  19. Application of a spectrum standardization method for carbon analysis in coal using laser-induced breakdown spectroscopy (LIBS).

    PubMed

    Li, Xiongwei; Wang, Zhe; Fu, Yangting; Li, Zheng; Liu, Jianmin; Ni, Weidou

    2014-01-01

    Measurement of coal carbon content using laser-induced breakdown spectroscopy (LIBS) is limited by its low precision and accuracy. A modified spectrum standardization method was proposed to achieve both reproducible and accurate results for the quantitative analysis of carbon content in coal using LIBS. The proposed method used the molecular emissions of diatomic carbon (C2) and cyanide (CN) to compensate for the diminution of atomic carbon emissions in high volatile content coal samples caused by matrix effect. The compensated carbon line intensities were further converted into an assumed standard state with standard plasma temperature, electron number density, and total number density of carbon, under which the carbon line intensity is proportional to its concentration in the coal samples. To obtain better compensation for fluctuations of total carbon number density, the segmental spectral area was used and an iterative algorithm was applied that is different from our previous spectrum standardization calculations. The modified spectrum standardization model was applied to the measurement of carbon content in 24 bituminous coal samples. The results demonstrate that the proposed method has superior performance over the generally applied normalization methods. The average relative standard deviation was 3.21%, the coefficient of determination was 0.90, the root mean square error of prediction was 2.24%, and the average maximum relative error for the modified model was 12.18%, showing an overall improvement over the corresponding values for the normalization with segmental spectrum area, 6.00%, 0.75, 3.77%, and 15.40%, respectively.

  20. Identification of metal elements by time-resolved LIBS technique in sediments lake the “Cisne”

    NASA Astrophysics Data System (ADS)

    Pacheco, P.; Arregui, E.; Álvarez, J.; Rangel, N.; Sarmiento, R.

    2017-01-01

    Laser induced breakdown spectroscopy (LIBS), is a kind of spectral method of atomic emission that uses pulses of radiation high energy laser as excitation source. One of the advantages of technical LIBS lies in the possibility of analyse the substances in any State of aggregation, already is solid, liquid or gaseous, even in colloids as aerosols, gels and others. Another advantage over other conventional techniques is the simultaneous analysis of elements present in a sample of multielement. This work is made in the use of this technique for the identification of metal pollutants in the Swan Lake sediment samples, collected by drilling cores. Plasmas were generated by focusing the radiation of Nd: YAG laser with an energy per pulse 13mJ and 4ns duration, wavelength of 532nm. The spectra of radiation from the plasmas of sediment were recorded with an Echelle spectrograph type coupled to an ICCD camera. The delay times were between 0.5μs and 7μs, while the gate width was of 2μs. To ensure the homogeneity of the plasmas, the sediment sample was placed in a positioning system of linear and rotary adjustment of smooth step synchronized with the trigger of the laser pulse. The registration of the spectra of the sediment to different times of delay, allowed to identify the lines prominent of the different elements present in the sample. The analysis of the Spectra allowed the identification of some elements in the sample as if, Ca, Na, Mg, and Al through the measurement of wavelengths of the prominent peaks.

  1. Coset construction of AdS particle dynamics

    NASA Astrophysics Data System (ADS)

    Heinze, Martin; Jorjadze, George; Megrelidze, Luka

    2017-01-01

    We analyze the dynamics of the AdSN+1 particle realized on the coset SO(2, N)/SO (1,N). Hamiltonian reduction provides the physical phase space in terms of the coadjoint orbit obtained by boosting a timelike element of 𝔰𝔬(2, N). We show equivalence of this approach to geometric quantization and to the SO(N) covariant oscillator description, for which the boost generators entail a complicated operator ordering. As an alternative scheme, we introduce dual oscillator variables and derive their algebra at the classical and the quantum levels. This simplifies the calculations of the commutators for the boost generators and leads to unitary irreducible representations of 𝔰𝔬(2, N) for all admissible values of the mass parameter. We furthermore discuss an SO(N) covariant supersymmetric extension of the oscillator quantization, with its realization for superparticles in AdS2 and AdS3 given by recent works.

  2. 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 .

  3. 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.

  4. 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.

  5. [Enteral tube feeding].

    PubMed

    Haller, Alois

    2014-03-01

    Tube feeding is an integral part of medical therapies, and can be easily managed also in the outpatient setting. Tube feeding by the stomach or small intestine with nasogastral or nasojejunal tubes is common in clinical practice. Long-term nutrition is usually provided through a permanent tube, i. e. a percutaneous endoscopic gastrostomy (PEG). Modern portable nutrition pumps are used to cover the patient's nutritional needs. Enteral nutrition is always indicated if patients can not or should not eat or if nutritional requirements cannot be covered within 3 days after an intervention, e. g. after abdominal surgery. Industrially produced tube feedings with defined substrate concentrations are being used; different compositions of nutrients, such as glutamine fish oil etc., are used dependent on the the condition of the patient. Enteral nutrition may be associated with complications of the tube, e. g. dislocation, malposition or obstruction, as well as the feeding itself, e. g.hyperglycaemia, electrolyte disturbances, refeeding syndrome diarrhea or aspiration). However, the benefit of tube feeding usually exceeds the potential harm substantially.

  6. Effect of liquid feeding weaned pigs on growth performance to harvest.

    PubMed

    Lawlor, P G; Lynch, P B; Gardiner, G E; Caffrey, P J; O'Doherty, J V

    2002-07-01

    Four experiments were undertaken to examine the effect of feeding postweaning diets as dry pelleted feed, fresh liquid feed, acidified liquid feed, and fermented liquid feed on pig performance from weaning (26 d) to harvest. In Exp. 1 (n = 12 replicates) and 2 (n = 10 replicates), the treatments were 1) dry pelleted feed and 2) fresh liquid feed. In Exp. 1, 2 kg of starter diet (16.7 MJ of DE/kg and 1.6% lysine) per pig and 5 kg of transition diet (16.7 MJ of DE/kg and 1.5% lysine) per pig followed by a weaner diet (14.0 MJ of DE/kg and 1.36% lysine) were offered to 27 d after weaning. In Exp. 3 (n = 8 replicates), the treatments were 1) dry pelleted feed, 2) fresh liquid feed, and 3) acidified liquid feed. In Exp. 4 (n = 8 replicates), the treatments were 1) dry pelleted feed, 2) acidified liquid feed, and 3) fermented liquid feed. In Exp. 2, 3, and 4, 3 kg of starter diet (16.1 MJ of DE/kg and 1.74% lysine) per pig and 6 kg of transition diet (15.3 MJ of DE/kg and 1.5% lysine) per pig followed by a weaner diet (14.0 MJ of DE/kg and 1.36% lysine) was offered to 27 d after weaning. All treatments were balanced for boars and gilts and diets were offered for ad libitum consumption. Acidified liquid feed was produced by adding lactic acid to the liquid feed so that its pH was decreased to 4.0. Fermented liquid feed was produced by adding an inoculum of Lactococcus lactis subsp. cremoris 303 (1.3%, vol/wt) to the first mix. In Exp. 1, ADG from weaning to d 27 after weaning was 338 and 286 g/d (SEM = 10; P < 0.01) and DM gain/feed in the same period was 888 and 594 g/kg (SEM = 23.1; P < 0.001) for dry pelleted feed and fresh liquid feed, respectively. In Exp. 2, ADG was 391 and 352 g/d (SEM = 6.4; P < 0.01) and DM gain/feed was 856 and 642 g/kg (SEM = 9.9; P < 0.001) for dry pelleted feed and fresh liquid feed, respectively, during the period from weaning to d 27 after weaning. In Exp. 3, ADG was 408, 416, and 433 g/d (SEM = 12.7; P > 0.05) and DM gain/feed was 865, 755

  7. Adding Economic Analysis to Intelligence Preparation of the Battlefield

    DTIC Science & Technology

    2008-03-07

    Adding Economic Analysis to Intelligence Preparation of the Battlefield” Clay D. Murray, Jr. Second Lieutenant, Military Intelligence US Army...Reserve 07 March 2008 Today, more than ever, economic analysis must be accounted for in Intelligence Preparation of the Battlefield (IPB). Army...in all of our fights around the world; economics. Throughout history, economic factors have been the tinder that feeds the flames of war. Economics

  8. 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.

  9. 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.

  10. 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

  11. A deformation of AdS5 × S5

    NASA Astrophysics Data System (ADS)

    Gauntlett, Jerome P.; Gutowski, Jan B.; Suryanarayana, Nemani V.

    2004-11-01

    We analyse a one-parameter family of supersymmetric solutions of type IIB supergravity that includes AdS5 × S5. For small values of the parameter the solutions are causally well behaved, but beyond a critical value closed timelike curves (CTCs) appear. The solutions are holographically dual to {\\cal N}=4 supersymmetric Yang Mills theory on a non-conformally flat background with non-vanishing R-currents. We compute the holographic energy momentum tensor for the spacetime and show that it remains finite even when the CTCs appear. The solutions, as well as the uplift of some recently discovered AdS5 black-hole solutions, are shown to preserve precisely two supersymmetries.

  12. Supersymmetric AdS_6 solutions of type IIB supergravity

    NASA Astrophysics Data System (ADS)

    Kim, Hyojoong; Kim, Nakwoo; Suh, Minwoo

    2015-10-01

    We study the general requirement for supersymmetric AdS_6 solutions in type IIB supergravity. We employ the Killing spinor technique and study the differential and algebraic relations among various Killing spinor bilinears to find the canonical form of the solutions. Our result agrees precisely with the work of Apruzzi et al. (JHEP 1411:099, 2014), which used the pure spinor technique. Hoping to identify the geometry of the problem, we also computed four-dimensional theory through the dimensional reduction of type IIB supergravity on AdS_6. This effective action is essentially a non-linear sigma model with five scalar fields parametrizing {SL}(3,{R})/{SO}(2,1), modified by a scalar potential and coupled to Einstein gravity in Euclidean signature. We argue that the scalar potential can be explained by a subgroup CSO(1,1,1) subset {SL}(3,{R}) in a way analogous to gauged supergravity.

  13. Universal isolation in the AdS landscape

    NASA Astrophysics Data System (ADS)

    Danielsson, U. H.; Dibitetto, G.; Vargas, S. C.

    2016-12-01

    We study the universal conditions for quantum nonperturbative stability against bubble nucleation for pertubatively stable AdS vacua based on positive energy theorems. We also compare our analysis with the preexisting ones in the literature carried out within the thin-wall approximation. The aforementioned criterion is then tested in two explicit examples describing massive type IIA string theory compactified on S3 and S3×S3, respectively. The AdS landscape of both classes of compactifications is known to consist of a set of isolated points. The main result is that all critical points respecting the Breitenlohner-Freedman (BF) bound also turn out be stable at a nonperturbative level. Finally, we speculate on the possible universal features that may be extracted from the above specific examples.

  14. Tachyon inflation in an AdS braneworld with backreaction

    NASA Astrophysics Data System (ADS)

    Bilić, Neven; Dimitrijevic, Dragoljub D.; Djordjevic, Goran S.; Milosevic, Milan

    2017-02-01

    We analyze the inflationary scenario based on the tachyon field coupled with the radion of the second Randall-Sundrum model (RSII). The tachyon Lagrangian is derived from the dynamics of a 3-brane moving in the five-dimensional bulk. The AdS5 geometry of the bulk is extended to include the radion. Using the Hamiltonian formalism we find four nonlinear field equations supplemented by the modified Friedmann equations of the RSII braneworld cosmology. After a suitable rescaling we reduce the parameters of our model to only one free parameter related to the brane tension and the AdS5 curvature. We solve the equations numerically assuming a reasonably wide range of initial conditions determined by physical considerations. Varying the free parameter and initial conditions we confront our results with the Planck 2015 data.

  15. Ambitwistors, oscillators and massless fields on AdS5

    NASA Astrophysics Data System (ADS)

    Uvarov, D. V.

    2016-11-01

    Positive energy unitary irreducible representations of SU (2 , 2) can be constructed with the aid of bosonic oscillators in (anti)fundamental representation of SU(2)L × SU(2)R that are closely related to Penrose twistors. Starting with the correspondence between the doubleton representations, homogeneous functions on projective twistor space and on-shell generalized Weyl curvature SL (2 , C) spinors and their low-spin counterparts, we study in the similar way the correspondence between the massless representations, homogeneous functions on ambitwistor space and, via the Penrose transform, with the gauge fields on Minkowski boundary of AdS5. The possibilities of reconstructing massless fields on AdS5 and some applications are also discussed.

  16. Generalised structures for N=1 AdS backgrounds

    NASA Astrophysics Data System (ADS)

    Coimbra, André; Strickland-Constable, Charles

    2016-11-01

    We expand upon a claim made in a recent paper [arXiv:1411.5721] that generic minimally supersymmetric AdS backgrounds of warped flux compactifications of Type II and M theory can be understood as satisfying a straightforward weak integrability condition in the language of {E}_{d(d)}× {R}+ generalised geometry. Namely, they are spaces admitting a generalised G-structure set by the Killing spinor and with constant singlet generalised intrinsic torsion.

  17. 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.

  18. 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...

  19. 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...

  20. 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…

  1. Gastrostomy feeding tube - bolus

    MedlinePlus

    Feeding - gastrostomy tube - bolus; G-tube - bolus; Gastrostomy button - bolus; Bard Button - bolus; MIC-KEY - bolus ... Your child's gastrostomy tube (G-tube) is a special tube in your child's stomach that will help deliver food and medicines until your ...

  2. 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…

  3. On information loss in AdS3/CFT2

    DOE PAGES

    Fitzpatrick, A. Liam; Kaplan, Jared; Li, Daliang; ...

    2016-05-18

    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 ofmore » correlators at times t ~SBH, 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. Lastly, our results suggest a line of inquiry towards a more precise formulation of the gravitational path integral in AdS3.« less

  4. Shock Wave Collisions and Thermalization in AdS_5

    NASA Astrophysics Data System (ADS)

    Kovchegov, Y. V.

    We study heavy ion collisions at strong 't Hooft coupling usingAdS/CFT correspondence. According to the AdS/CFT dictionary heavy ion collisions correspond to gravitational shock wave collisions in AdS_5. We construct the metric in the forward light cone after the collision perturbatively through expansion of Einstein equations in graviton exchanges. We obtain an analytic expression for the metric including all-order graviton exchanges with one shock wave, while keeping the exchanges with another shock wave at the lowest order. We read off the corresponding energy-momentum tensor of the produced medium. Unfortunately this energy-momentum tensor does not correspond to ideal hydrodynamics, indicating that higher order graviton exchanges are needed to construct the full solution of the problem. We also show that shock waves must completely stop almost immediately after the collision in AdS_5, which, on the field theory side, corresponds to complete nuclear stopping due to strong coupling effects, likely leading to Landau hydrodynamics. Finally, we perform trapped surface analysis of the shock wave collisions demonstrating that a bulk black hole, corresponding to ideal hydrodynamics on the boundary, has to be created in such collisions, thus constructing a proof of thermalization in heavy ion collisions at strong coupling.

  5. 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

  6. 21 CFR 558.5 - Requirements for liquid medicated feed.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Requirements for liquid medicated feed. 558.5 Section 558.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-dressing (adding on top of the usual ration) (§ 558.3(b)(4)). (b) How is liquid free-choice medicated...

  7. Effect of four levels of added fat on broiler breeder performance.

    PubMed

    Brake, J

    1990-10-01

    Broiler breeders were fed corn-soybean diets and reared under 8 h of incandescent light. Birds were photostimulated with a mixture of incandescent light and daylight at 20 wk of age. Corn-soybean breeder diets with 0, 2, 4, and 6% added poultry fat were fed from 24 to 64 wk of age. Daily feed allocations were adjusted to provide comparable calculated protein intake at peak egg production; calculated ME intake was 413, 437, 461, and 484 kcal per bird per day for the 0, 2, 4, and 6% added fat diets, respectively. Feed was gradually reduced such that ME intake reached 400, 415, 429, and 422 kcal ME per bird per day from 57 to 64 wk of age for the respective diets. When compared with 0%, all levels of added fat significantly increased egg production and feed conversion. Fertility was increased significantly with the 4% added fat when compared with fertility at 2%; fertility with 0 or 6% added fat was intermediate. Female body weight increased in a dose-related manner in response to added fat. Chicks per hen was maximized at 4% added fat. Taken together, the data are interpreted to mean that 4% added fat is near the optimum for broiler breeders.

  8. Effect of early feed restriction and enzyme supplementation on digestive enzyme activities in broilers.

    PubMed

    Pinheiro, D F; Cruz, V C; Sartori, J R; Vicentini Paulino, M L M

    2004-09-01

    The effect of feed restriction and enzymatic supplementation on intestinal and pancreatic enzyme activities and weight gain was studied in broiler chickens. Quantitative feed restriction was applied to chickens from 7 to 14 d of age. An enzyme complex mainly consisting of protease and amylase was added to the chicken ration from hatching to the end of the experiment. Birds subjected to feed restriction whose diet was not supplemented showed an increase in sucrase, amylase, and lipase activities immediately after the restriction period. Amylase, lipase, and chymotrypsin activities were higher in chickens subjected to feed restriction and fed a supplemented diet than in those only subjected to feed restriction. Trypsin activity increased after feed restriction and after supplementation, but there was no interaction between these effects. Early feed restriction had no effect on enzyme activity in 42-d-old chickens. Chickens subjected to early restriction and fed the supplemented diet presented higher sucrase, maltase, and lipase activities than nonsupplemented ones (P < 0.05). There was no effect of early feed restriction or diet supplementation on weight gain to 42 d. Percentage weight gain from 14 to 42 d of age was equivalent in feed-restricted and ad libitum fed birds. Feed-restricted broilers fed a supplemented diet showed a higher percentage weight gain than nonsupplemented birds. We conclude that enzymatic supplementation potentiates the effect of feed restriction on digestive enzyme activity and on weight gain.

  9. The generalized added mass revised

    NASA Astrophysics Data System (ADS)

    De Wilde, Juray

    2007-05-01

    The reformulation of the generalized or apparent added mass presented by De Wilde [Phys. Fluids 17, 113304 (2005)] neglects the presence of a drag-type force in the gas and solid phase momentum equations. Reformulating the generalized added mass accounting for the presence of a drag-type force, an apparent drag force appears next to the apparent distribution of the filtered gas phase pressure gradient over the phases already found by De Wilde in the above-cited reference. The reformulation of the generalized added mass and the evaluation of a linear wave propagation speed test then suggest a generalized added mass type closure approach to completely describe filtered gas-solid momentum transfer, that is, including both the filtered drag force and the correlation between the solid volume fraction and the gas phase pressure gradient.

  10. Effect of social housing on the development of feeding behavior and social feeding preferences of dairy calves.

    PubMed

    Miller-Cushon, E K; DeVries, T J

    2016-02-01

    This study investigated how social housing affects pre- and postweaning feeding behavior and social feeding preferences of dairy calves. Twenty Holstein bull calves were housed either individually (IH; 10 calves) or in pairs (PH; 10 calves) from birth. Calves were offered grain concentrate and milk replacer ad libitum via an artificial teat (1 teat provided per calf) and weaned by incrementally diluting the milk replacer from 39 to 49 d of age. Postweaning, IH calves were paired within treatment and all pens (n=5 per treatment) were offered a complete pelleted diet ad libitum and followed until 13 wk of age. We recorded feeding times from video for 3 consecutive days in wk 6, 9, and 12 of age and used this to calculate daily meal frequency and meal duration. In wk 9 and 12, frequency and duration of synchronized feeding were also calculated. In addition, preference tests were conducted at time of feed delivery in wk 10 to assess the preference of each calf to feed alongside or out of visual contact of their pen mate. Pair-housed calves consumed more concentrate, in more frequent meals, than IH calves in the week before weaning (wk 6) and continued to have greater concentrate intake during weaning. Milk intake was not affected by treatment, but calves in PH pens consumed their milk in more frequent and smaller meals. Postweaning, intake was similar between treatments, but calves raised in PH pens continued to have meals that were more frequent and shorter in duration. Both treatments had a similar frequency of synchronized meals. However, when offered a choice to feed alone or alongside their pen mate during preference testing, calves raised in PH pens spent more time feeding in the presence of their pen mate than calves raised in IH pens. These results suggest that meal patterns established in response to different early social environments may persist after weaning and that early social contact may have longer-term effects on social feeding behavior.

  11. AD-1 aircraft in flight

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The Ames-Dryden (AD)-1 was a research aircraft designed to investigate the concept of an oblique (or pivoting) wing. The movie clip runs about 17 seconds and has two air-to-air views of the AD-1. The first shot is from slightly above as the wing pivots to 60 degrees. The other angle is almost directly below the aircraft when the wing is fully pivoted.

  12. The influence of loose-mix feeding on behavior, feed intake, and body weight of growing geese.

    PubMed

    Arroyo, J; Auvergne, A; Dubois, J P; Lavigne, F; Bijja, M; Bannelier, C; Fortun-Lamothe, L

    2013-06-01

    The aim of this trial was to study the influence of loose-mix feeding on behavior, feed intake, and BW of growing geese. In total, 252 one-day-old geese (Anser anser) were divided into 2 groups differing in the form of diet they received between 42 and 98 d of age (AMEn 11.55 MJ/kg, CP 16%): a complete pelleted diet containing 500 g of sorghum/kg (control group) or a mixture containing 500 g of protein-rich pellets and 500 g of sorghum whole seeds/kg (mixed group). Feed intake was measured daily from 42 to 48 d and every 3 d from 49 to 98 d. Individual BW was measured weekly from 42 to 98 d. Goose behavior was monitored by the scan sampling method throughout the experiment, which was divided into 5 periods according to the timing of access to feed: period 1 from 42 to 55 d (ad libitum feeding access), period 2 from 56 to 62 d (2 + 2 h feeding access), period 3 from 63 to 70 d (2 h feeding access), period 4 from 71 to 94 d (1 h feeding access), and period 5 from 95 to 97 d (3 h feeding access). Over the whole period, the feed intake (13,968 and 14,480 g) and the feed conversion ratio (8.53 and 8.15) were similar in both groups (P = 0.112 and P = 0.168; respectively). Body weight was similar in both groups from 42 to 91 d of age, but at 98 d of age, BW was 3.7% lower in the control than in the mixed group (P = 0.006). Goose behavior was influenced by period, because the percentage of birds feeding increased when the daily access time to the feed decreased (P < 0.001), but not by group (P > 0.05). The results suggest that a loose-mix feeding could be recommended in feeding of growing geese because it weakly influences their feed behavior but slightly increases their weight at the end of the growing period.

  13. Feeding rate as valuable information in primate feeding ecology.

    PubMed

    Nakagawa, Naofumi

    2009-04-01

    In this review I outline studies on wild non-human primates using information on feeding rate, which is defined as the food intake per minute on a dry-weight basis; further, I summarize the significance of feeding rate in primate feeding ecology. The optimal foraging theory has addressed three aspects of animal feeding: (1) optimal food patch choice, (2) optimal time allocation to different patches, and (3) optimal food choice. In order to gain a better understanding of these three aspects, the feeding rate itself or its relevance indices (e.g., rates of calorie and protein intake) could be appropriate measures to assess the quality of food and food patches. Moreover, the feeding rate plays an essential role in estimation of total food intake, because it varies greatly for different food items and the feeding time is not a precise measure. The feeding rate could also vary across individuals who simultaneously feed on the same food items in the same food patch. Body size-dependent and rank-dependent differences in the feeding rate sometimes cause individuals to take strategic behavioral options. In the closing remarks, I discuss the usefulness of even limited data on feeding rate obtained under adverse observational conditions in understanding primate feeding ecology.

  14. 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

  15. 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.

  16. Islam and infant feeding.

    PubMed

    Shaikh, Ulfat; Ahmed, Omar

    2006-01-01

    Few physicians in the United States receive formal education related to principles of infant care in Islamic families. Breastfeeding has a religious basis in Islam and it is recommended that the mother suckle her offspring for 2 years if possible. Weaning from the breast before that period is allowed if mutually decided on by both parents. The infant's father has an obligation to support his wife through any circumstances that may affect breastfeeding and, in case of divorce, provide shelter and financial support to the mother-infant dyad for as long as breastfeeding continues. By showing understanding and respect of Islamic beliefs related to infant feeding, clinicians can help support healthy early feeding of Muslim infants.

  17. Euclidean and Noetherian entropies in AdS space

    SciTech Connect

    Dutta, Suvankar; Gopakumar, Rajesh

    2006-08-15

    We examine the Euclidean action approach, as well as that of Wald, to the entropy of black holes in asymptotically AdS spaces. From the point of view of holography these two approaches are somewhat complementary in spirit and it is not obvious why they should give the same answer in the presence of arbitrary higher derivative gravity corrections. For the case of the AdS{sub 5} Schwarzschild black hole, we explicitly study the leading correction to the Bekenstein-Hawking entropy in the presence of a variety of higher derivative corrections studied in the literature, including the Type IIB R{sup 4} term. We find a nontrivial agreement between the two approaches in every case. Finally, we give a general way of understanding the equivalence of these two approaches.

  18. Use of the near vacuum UV spectral range for the analysis of W-based materials for fusion applications using LIBS

    NASA Astrophysics Data System (ADS)

    Pribula, M.; Krištof, J.; Suchoňová, M.; Horňáčková, M.; Plavčan, J.; Hakola, A.; Veis, P.

    2016-02-01

    The vacuum UV (VUV)-near Infrared (NIR) laser induced breakdown spectroscopy (LIBS) technique was applied to investigate the composition of W-based samples with a protective carbon layer. The sample was analyzed under pressures from 5 to 105 Pa and atmosphere (air, He). The spectra were recorded with three spectrometers at delays from 200 ns to 10 μs at atmospheric pressures and from 100 to 500 ns at low pressures. The electron density was determined from the measured spectra using Stark broadening and the electron temperature from the W I-W III Saha-plot in the VUV-NIR spectral range. The better precision was achieved due to usage W III spectral lines of tungsten. The achieved results are more reliable than results obtained without W III spectral lines. The calibration free LIBS method was then applied to determine the W and C contents of the analyzed sample.

  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.

  20. 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).

  1. 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

  2. Heavy quark potential from deformed AdS5 models

    NASA Astrophysics Data System (ADS)

    Zhang, Zi-qiang; Hou, De-fu; Chen, Gang

    2017-04-01

    In this paper, we investigate the heavy quark potential in some holographic QCD models. The calculation relies on a modified renormalization scheme mentioned in a previous work of Albacete et al. After studying the heavy quark potential in Pirner-Galow model and Andreev-Zakharov model, we extend the discussion to a general deformed AdS5 case. It is shown that the obtained potential is negative definite for all quark-antiquark separations, differs from that using the usual renormalization scheme.

  3. 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.

  4. 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.

  5. 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.

  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.

  7. 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

  8. Short Communication on "Direct compositional quantification of (U-Th)O2 - MOX nuclear fuel using ns-UV-LIBS and chemometric regression models"

    NASA Astrophysics Data System (ADS)

    Singh, Manjeet; Sarkar, Arnab; Mao, Xianglei; Russo, Richard E.

    2017-02-01

    The determination of uranium with composition varying from 0% to 35 wt% in (Th-U)O2 mixed oxide fuel using laser induced breakdown spectroscopy (LIBS) utilizing partial least square regression (PLSR) has been demonstrated. Good agreement between expected and experiment results using 266 nm, 532 nm and 1064 nm was shown. The analytical results at 266 nm of 2-3% precision and ∼1% accuracy (bias) satisfy the acceptance criteria range for chemical analysis in the nuclear industry.

  9. Overview of FEED, the Feeding Experiments End-user Database

    PubMed Central

    Wall, Christine E.; Vinyard, Christopher J.; Williams, Susan H.; Gapeyev, Vladimir; Liu, Xianhua; Lapp, Hilmar; German, Rebecca Z.

    2011-01-01

    The Feeding Experiments End-user Database (FEED) is a research tool developed by the Mammalian Feeding Working Group at the National Evolutionary Synthesis Center that permits synthetic, evolutionary analyses of the physiology of mammalian feeding. The tasks of the Working Group are to compile physiologic data sets into a uniform digital format stored at a central source, develop a standardized terminology for describing and organizing the data, and carry out a set of novel analyses using FEED. FEED contains raw physiologic data linked to extensive metadata. It serves as an archive for a large number of existing data sets and a repository for future data sets. The metadata are stored as text and images that describe experimental protocols, research subjects, and anatomical information. The metadata incorporate controlled vocabularies to allow consistent use of the terms used to describe and organize the physiologic data. The planned analyses address long-standing questions concerning the phylogenetic distribution of phenotypes involving muscle anatomy and feeding physiology among mammals, the presence and nature of motor pattern conservation in the mammalian feeding muscles, and the extent to which suckling constrains the evolution of feeding behavior in adult mammals. We expect FEED to be a growing digital archive that will facilitate new research into understanding the evolution of feeding anatomy. PMID:21700574

  10. 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.

  11. Spectral identifiers from roasting process of Arabica and Robusta green beans using Laser-Induced Breakdown Spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Wirani, Ayu Puspa; Nasution, Aulia; Suyanto, Hery

    2016-11-01

    Coffee (Coffea spp.) is one of the most widely consumed beverages in the world. World coffee consumption is around 70% comes from Arabica, 26% from Robusta , and the rest 4% from other varieties. Coffee beverages characteristics are related to chemical compositions of its roasted beans. Usually testing of coffee quality is subjectively tasted by an experienced coffee tester. An objective quantitative technique to analyze the chemical contents of coffee beans using LIBS will be reported in this paper. Optimum experimental conditions was using of 120 mJ of laser energy and delay time 1 μs. Elements contained in coffee beans are Ca, W, Sr, Mg, Na, H, K, O, Rb, and Be. The Calcium (Ca) is the main element in the coffee beans. Roasting process will cause the emission intensity of Ca decreased by 42.45%. In addition, discriminant analysis was used to distinguish the arabica and robusta variants, either in its green and roasted coffee beans. Observed identifier elements are Ca, W, Sr, and Mg. Overall chemical composition of roasted coffee beans are affected by many factors, such as the composition of the soil, the location, the weather in the neighborhood of its plantation, and the post-harvesting process of the green coffee beans (drying, storage, fermentation, and roasting methods used).

  12. Laser-Induced Breakdown Spectroscopy (LIBS) for spectral characterization of regular coffee beans and luwak coffee bean

    NASA Astrophysics Data System (ADS)

    Nufiqurakhmah, Nufiqurakhmah; Nasution, Aulia; Suyanto, Hery

    2016-11-01

    Luwak (civet) coffee refers to a type of coffee, where the cherries have been priorly digested and then defecated by a civet (Paradoxurus Hermaphroditus), a catlike animals typically habited in Indonesia. Luwak will only selectively select ripe cherries, and digesting them by enzymatic fermentation in its digestive system. The defecated beans is then removed and cleaned from the feces. It is regarded as the world's most expensive coffee, Traditionally the quality of the coffee is subjectively determined by a tester. This research is motivated by the needs to study and develop quantitative parameters in determining the quality of coffee bean, which are more objective to measure the quality of coffee products. LIBS technique was used to identify the elemental contents of coffee beans based on its spectral characteristics in the range 200-900 nm. Samples of green beans from variant of arabica and robusta, either regular and luwak, were collected from 5 plantations in East Java. From the recorded spectra, intensity ratio of nitrogen (N), hydrogen (H), and oxygen (O) as essential elements in coffee is applied. In general, values extracted from luwak coffee bean is higher with increases 0.03% - 79.93%. A Discriminant Function Analysis (DFA) also applied to identify marker elements that characterize the regular and luwak beans. Elements of Ca, W, Sr, Mg, and H are the ones used to differentiate the regular and luwak beans from arabica variant, while Ca and W are the ones used to differentiate the regular and luwak beans of robusta variant.

  13. Study of adsorption Ag and Pb in liquid sample using Berea sandstone by commercial laser-induced breakdown spectroscopy (LIBS)

    NASA Astrophysics Data System (ADS)

    Suyanto, H.; Wendri, N.; Agustiningrum, U.; Manurung, M.

    2016-11-01

    Qualitative and quantitative analysis of Pb and Ag elements in liquid samples had been done by commercial laser-induced breakdown spectroscopy (LIBS) using adsorption method on a Berea Sandstone. The aim of this study is to identify the thickness of the Berea Sandstone for adsorbing Pb and Ag elements in liquid. The experiment was started with characterizing the Berea Sandstone that contains Si, Na, H, Li, K, Ca, O, N, Be, Ti, Al, Mg and Ba. Some of these elements have ability to adsorb Pb and Ag elements in the liquid. To prove this phenomenon, it is required to look for the experiment parameter optimum conditions such as laser energy, adsorption time and sample temperature. The experiment was conducted by dropping 2 ml standard liquid containing 1000 ppm of Pb and Ag to the Berea Sandstone surface. The result showed that the parameter optimum conditions for analyzing Pb and Ag elements in liquid sample with adsorption method were adsorption delay-time of 15 minutes, laser energy of 120 mJ and sample heating of 80 °C. The next experiment was focused on the number of adsorption as a function of depth. The data showed that Pb and Ag elements in liquid sample of 2 ml, 1000 ppm were fully adsorbed by the Berea Sandstone until the depth of 0.372 mm and 10.40 mm from the surface, respectively. The data also showed that the limit of detection predicted to about 22.76 ppm.

  14. 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.

  15. Use of the EUR LiB 15/5 data set for radiation shielding calculations in iron

    NASA Astrophysics Data System (ADS)

    Abdo, A. El-Sayed; Bashter, I. I.; Kansouh, W. A.

    The shielding effect of an iron sphere assembly has been tested for a Pu-α-Be neutron source placed in the center of the shield assembly. Emergent neutron and gamma spectra were measured with a stilbene scintillation counter. Discrimination between neutrons and gammas was achieved by the pulse shape discrimination technique based on the zero crossing method. Calculations have been made using the one-dimensional transport code ANISN-Westinghouse version (ANISN-W) and the EUR LiB 15/5 cross section data set. The agreement between measurements and calculations indicates that the cross section set and the calculation model are suitable for studying the iron shielding experiments over the neutron energy range 1.35-10 MeV and the gamma energy range 0.3-6 MeV. Total macroscopic cross sections for fast neutrons, linear attenuation coefficients for gamma rays and half-value thicknesses for neutrons and gammas for the whole energy range and at different energies have been obtained.

  16. 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

  17. Effectiveness and residues of procymidone applied on celery and fennel in the control of Sclerotinia sclerotiorum (Lib.) de Bary.

    PubMed

    Pompi, V; Galli, M; Leandri, A; Forchielli, L

    2005-01-01

    A biennial experimentation has been led using the active ingredient (a.i.) procymidone, for the control of Sclerotinia sclerotiorum (Lib.) De Bary on fennel and celery. At present this utilizathion it is not authorized, even though this "minor use" is considered essential for the control of the various phytopathologies. For every test, both in field and in greenhouse, two treatments to the dose of 40 g/hl of a.i. have been made. After the second treatment two assessments were led to check effectiveness of a.i. and subsequent vegetable samplings have been made to determine the entity and the persistence of the residues of the used active ingredient. At the end of the agricultural cycle, in all the tests a good control of the infection caused by the fungus has been found; statistically significant differences of the infection between treated plots and the control. At harvesting (21 days from the 2nd treatment) we have found a residue average value of 0.1-0.2 mg/kg (field) and 0.3-0.4 mg/kg (greenhouse) on fennel and of: 1.0-1.5 mg/kg (field) e 3.0-3.5 mg/kg (greenhouse) on celery.

  18. arriba-lib: Analyses of user interactions with an electronic library of decision aids on the basis of log data.

    PubMed

    Hirsch, Oliver; Szabo, Elisabeth; Keller, Heidemarie; Kramer, Lena; Krones, Tanja; Donner-Banzhoff, Norbert

    2012-12-01

    Computerised log files are important for analysing user behaviour in health informatics to gain insight into processes that lead to suboptimal user patterns. This is important for software training programmes or for changes to improve usability. Technical user behaviour regarding decision aids has not so far been thoroughly investigated with log files. The aim of our study was to examine more detailed user interactions of primary-care physicians and their patients with arriba-lib, our multimodular electronic library of decision aids used during consultations, on the basis of log data. We analysed 184 consultation log files from 28 primary-care physicians. The average consultation time of our modules was about 8 min. Two-thirds of the consultation time were spent in the history information part of the programme. In this part, mainly bar charts were used to display risk information. Our electronic library of decision aids does not generate specific user behaviour based on physician characteristics such as age, gender, years in practice, or prior experience with decision aids. This supports the widespread use of our e-library in the primary-care sector and probably beyond.

  19. 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.

  20. LibHalfSpace: A C++ object-oriented library to study deformation and stress in elastic half-spaces

    NASA Astrophysics Data System (ADS)

    Ferrari, Claudio; Bonafede, Maurizio; Belardinelli, Maria Elina

    2016-11-01

    The study of deformation processes in elastic half-spaces is widely employed for many purposes (e.g. didactic, scientific investigation of real processes, inversion of geodetic data, etc.). We present a coherent programming interface containing a set of tools designed to make easier and faster the study of processes in an elastic half-space. LibHalfSpace is presented in the form of an object-oriented library. A set of well known and frequently used source models (Mogi source, penny shaped horizontal crack, inflating spheroid, Okada rectangular dislocation, etc.) are implemented to describe the potential usage and the versatility of the library. The common interface given to library tools enables us to switch easily among the effects produced by different deformation sources that can be monitored at the free surface. Furthermore, the library also offers an interface which simplifies the creation of new source models exploiting the features of object-oriented programming (OOP). These source models can be built as distributions of rectangular boundary elements. In order to better explain how new models can be deployed some examples are included in the library.

  1. 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.

  2. Sensitivity, stability, and precision of quantitative Ns-LIBS-based fuel-air-ratio measurements for methane-air flames at 1-11 bar.

    PubMed

    Hsu, Paul S; Gragston, Mark; Wu, Yue; Zhang, Zhili; Patnaik, Anil K; Kiefer, Johannes; Roy, Sukesh; Gord, James R

    2016-10-01

    Nanosecond laser-induced breakdown spectroscopy (ns-LIBS) is employed for quantitative local fuel-air (F/A) ratio (i.e., ratio of actual fuel-to-oxidizer mass over ratio of fuel-to-oxidizer mass at stoichiometry, measurements in well-characterized methane-air flames at pressures of 1-11 bar). We selected nitrogen and hydrogen atomic-emission lines at 568 nm and 656 nm, respectively, to establish a correlation between the line intensities and the F/A ratio. We have investigated the effects of laser-pulse energy, camera gate delay, and pressure on the sensitivity, stability, and precision of the quantitative ns-LIBS F/A ratio measurements. We determined the optimal laser energy and camera gate delay for each pressure condition and found that measurement stability and precision are degraded with an increase in pressure. We have identified primary limitations of the F/A ratio measurement employing ns-LIBS at elevated pressures as instabilities caused by the higher density laser-induced plasma and the presence of the higher level of soot. Potential improvements are suggested.

  3. 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.

  4. 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.

  5. Primordial fluctuations from complex AdS saddle points

    SciTech Connect

    Hertog, Thomas; Woerd, Ellen van der E-mail: ellen@itf.fys.kuleuven.be

    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.

  6. 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.

  7. AdS nonlinear instability: moving beyond spherical symmetry

    NASA Astrophysics Data System (ADS)

    Dias, Óscar J. C.; Santos, Jorge E.

    2016-12-01

    Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation (Dafermos and Holzegel 2006 Seminar at DAMTP (University of Cambridge) available at https://dpmms.cam.ac.uk/~md384/ADSinstability.pdf, Bizon and Rostworowski 2011 Phys. Rev. Lett. 107 031102). We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied by Bizon and Rostworowski. In contrast with Bizon and Rostworowski, we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied by Bizon and Rostworowski. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of Bizon and Rostworowski. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.

  8. Strings on AdS wormholes and nonsingular black holes

    NASA Astrophysics Data System (ADS)

    Lü, H.; Vázquez-Poritz, Justin F.; Zhang, Zhibai

    2015-01-01

    Certain AdS black holes in the STU model can be conformally scaled to wormhole and black hole backgrounds which have two asymptotically AdS regions and are completely free of curvature singularities. While there is a delta-function source for the dilaton, classical string probes are not sensitive to this singularity. According to the AdS/CFT correspondence, the dual field theory lives on the union of the disjoint boundaries. For the wormhole background, causal contact exists between the two boundaries and the structure of certain correlation functions is indicative of an interacting phase for which there is a coupling between the degrees of freedom living at each boundary. The nonsingular black hole describes an entangled state in two non-interacting identical conformal field theories. By studying the behavior of open strings on these backgrounds, we extract a number of features of the ‘quarks’ and ‘anti-quarks’ that live in the field theories. In the interacting phase, we find that there is a maximum speed with which the quarks can move without losing energy, beyond which energy is transferred from a quark in one field theory to a quark in the other. We also compute the rate at which moving quarks within entangled states lose energy to the two surrounding plasmas. While a quark-antiquark pair within a single field theory exhibits Coulomb interaction for small separation, a quark in one field theory exhibits spring-like confinement with an anti-quark in the other field theory. For the entangled states, we study how the quark-antiquark screening length depends on temperature and chemical potential.

  9. Fermented liquid feed for pigs.

    PubMed

    Missotten, Joris A M; Michiels, Joris; Ovyn, Anneke; De Smet, Stefaan; Dierick, Noël A

    2010-12-01

    Since the announcement of the ban on the use of antibiotics as antimicrobial growth promoters in the feed of pigs in 2006 the investigation towards alternative feed additives has augmented considerably. Although fermented liquid feed is not an additive, but a feeding strategy, the experimental work examining its possible advantages also saw a rise. The use of fermented liquid feed (FLF) has two main advantages, namely that the simultaneous provision of feed and water may result in an alleviation of the transition from the sow milk to solid feed and may also reduce the time spent to find both sources of nutrients, and secondly, that offering FLF with a low pH may strengthen the potential of the stomach as a first line of defence against possible pathogenic infections. Because of these two advantages, FLF is often stated as an ideal feed for weaned piglets. The results obtained so far are rather variable, but in general they show a better body weight gain and worse feed/gain ratio for the piglets. However, for growing-finishing pigs on average a better feed/gain ratio is found compared to pigs fed dry feed. This better performance is mostly associated with less harmful microbiota and better gut morphology. This review provides an overview of the current knowledge of FLF for pigs,dealing with the FLF itself as well as its effect on the gastrointestinal tract and animal performance.

  10. Infant feeding and respiratory allergy.

    PubMed

    Murray, A B

    1971-03-06

    In addition to the potential dangers of feeding cow's milk to the newborn which you list in your editorial on infant feeding (January 2, p.30), other hazards have been proposed. 1 apparent consequence, reported by Johnston and Dutton, is an increased prevalence of allergy later in childhood. We examined this thesis in the course of a study on hearing loss in Vancouver primary school children. A trained interviewer put precoded questions to the children's mothers, 1 of which was whether the child had received any food other than breastmilk in the 1st month of the child's life. Another was whether she or the father or any of the child's siblings had ever had asthma, eczema, or hay fever, i.e., whether there was an immediate family history of allergy. A smear of the child's nasal secretions was made and was subsequently examined for eosinophils by a technician. If there were 10 eosinophils/highpower field in any 2 highpower fields, the child was said to have a nasal secretion eosinophilia. This appears to be a useful sign of allergic rhinitis. In the group with an immediate family history of allergy, the association between early introduction of foreign food and the presence of nasal secretion eosinophilia was significantly positive at the 5% level by the chi square test of association. For those children who received supplemental foods in the 1st month, 22 (32%) showed evidence of nasal secretion eosinophilia; 46 (68%) did not. Only 2 (11%) of those on breastmilk alone displayed this sign and 16 (89%) did not. In the remaining 233 children who did not have an immediate family history of allergy the association was not significantly positive. The sequence of events leading to respiratory allergy may be as follows: a neonate not only drinks his weight in cow's milk in a week, but also absorbs a disproportionately large amount of immunologically intact protein. Thus it would not be surprising to find a relatively high incidence of cow's milk allergy in genetically

  11. Plasticity in response to feed availability: Does feeding regime influence the relative growth performance of domesticated, wild and hybrid Atlantic salmon Salmo salar parr?

    PubMed

    Harvey, A C; Solberg, M F; Glover, K A; Taylor, M I; Creer, S; Carvalho, G R

    2016-09-01

    Growth of farmed, wild and F1 hybrid Atlantic salmon parr Salmo salar was investigated under three contrasting feeding regimes in order to understand how varying levels of food availability affects relative growth. Treatments consisted of standard hatchery feeding (ad libitum), access to feed for 4 h every day, and access to feed for 24 h on three alternate days weekly. Mortality was low in all treatments, and food availability had no effect on survival of all groups. The offspring of farmed S. salar significantly outgrew the wild S. salar, while hybrids displayed intermediate growth. Furthermore, the relative growth differences between the farmed and wild S. salar did not change across feeding treatments, indicating a similar plasticity in response to feed availability. Although undertaken in a hatchery setting, these results suggest that food availability may not be the sole driver behind the observed reduced growth differences found between farmed and wild fishes under natural conditions.

  12. Analysis of self-feeding in children with feeding disorders.

    PubMed

    Rivas, Kristi M; Piazza, Cathleen C; Roane, Henry S; Volkert, Valerie M; Stewart, Victoria; Kadey, Heather J; Groff, Rebecca A

    2014-01-01

    In the current investigation, we evaluated a method for increasing self-feeding with 3 children with a history of food refusal. The children never (2 children) or rarely (1 child) self-fed bites of food when the choice was between self-feeding and escape from eating. When the choice was between self-feeding 1 bite of food or being fed an identical bite of food, self-feeding was low (2 children) or variable (1 child). Levels of self-feeding increased for 2 children when the choice was between self-feeding 1 bite of food or being fed multiple bites of the same food. For the 3rd child, self-feeding increased when the choice was between self-feeding 1 bite of food or being fed multiple bites of a less preferred food. The results showed that altering the contingencies associated with being fed increased the probability of self-feeding, but the specific manipulations that produced self-feeding were unique to each child.

  13. Feeding the feeder

    NASA Technical Reports Server (NTRS)

    Kurylchek, A. L.

    1977-01-01

    Too often the equipment used to move difficult to handle powdery material from a hopper to process creates a complex of devices whose end result falls short on good performance...simply because equipment design, in many cases, has not kept up with advanced technological concepts in fine powder handling. The Feeder, being the key to an efficient feed system, must be assured a continuous flow from the storage tank...without bridging, arching, spasmodic flow or uncontrolled flushing. The causes and effects of flow problems are discussed and also solutions are offered based on the combination of theoretical and practical experience.

  14. Food and feed enzymes.

    PubMed

    Fraatz, Marco Alexander; Rühl, Martin; Zorn, Holger

    2014-01-01

    Humans have benefited from the unique catalytic properties of enzymes, in particular for food production, for thousands of years. Prominent examples include the production of fermented alcoholic beverages, such as beer and wine, as well as bakery and dairy products. The chapter reviews the historic background of the development of modern enzyme technology and provides an overview of the industrial food and feed enzymes currently available on the world market. The chapter highlights enzyme applications for the improvement of resource efficiency, the biopreservation of food, and the treatment of food intolerances. Further topics address the improvement of food safety and food quality.

  15. 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...

  16. Separating Growth from Value Added

    ERIC Educational Resources Information Center

    Yeagley, Raymond

    2007-01-01

    This article discusses Rochester's two academic models that offer different tools for different purposes--measuring individual learning and measuring what affects learning. The main focus of currently available growth measures is formative assessment--providing data to inform instructional planning. Value-added assessment is not a student…

  17. Adding Value to Indiana's Commodities.

    ERIC Educational Resources Information Center

    Welch, Mary A., Ed.

    1995-01-01

    Food processing plants are adding value to bulk and intermediate products to sell overseas. The Asian Pacific Rim economies constituted the largest market for consumer food products in 1993. This shift toward consumer food imports in this area is due to more women working outside the home, the internationalization of populations, and dramatic…

  18. Courtship American Style: Newspaper Ads

    ERIC Educational Resources Information Center

    Cameron, Catherine; And Others

    1977-01-01

    This study investigated an increasing social phenomenon--newspaper advertising for dating or marital partners--in terms of the bargaining process involved. Content analysis of personal ads in a popular "respectable" singles newspaper revealed a pattern of offers and requests reminiscent of a heterosexual stock market. (Author)

  19. Decreased regurgitation with a soy formula containing added soy fiber.

    PubMed

    Ostrom, Karin M; Jacobs, Joan R; Merritt, Russell J; Murray, Robert D

    2006-01-01

    The objective of this randomized study was to determine if fiber-supplemented soy formula reduced regurgitation in young infants. We compared regurgitation in 179 infants randomly assigned cow's milk-based (CM, 90) formula or soy formula with fiber (SF, 89). Initial daily incidence was similar (CM, 3.6; SF, 3.9 episodes), but significantly lower after 7 days on SF (CM, 3.4; SF, 2.3; p = 0.001). Less frequent regurgitation after 7 days on SF was sustained after 28 days (CM, 48%; SF, 31% of feedings; p = 0.001). Feeding SF effectively managed regurgitation while providing balanced nutrition without altering caloric distribution as occurs with adding rice cereal to formula.

  20. 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.

  1. Supersymmetry Properties of AdS Supergravity Backgrounds

    NASA Astrophysics Data System (ADS)

    Beck, Samuel; Gutowski, Jan; Papadopoulos, George

    2017-01-01

    Anti-de Sitter supergravity backgrounds are of particular interest in light of the AdS/CFT correspondence, which relates them to dual conformal field theories on the boundary of the anti-de Sitter space. We have investigated the forms of the supersymmetries these backgrounds preserve by solving the Killing spinor equations on the anti-de Sitter components of these spaces. We have found that a supersymmetric AdSn background necessarily preserves 2⌊n/2⌋ k supersymmetries for n <= 4 and 2 ⌊n/2 ⌋ + 1 k supersymmetries for 4 < n <= 7 , k ∈N> 0 . Additionally, we have found that the Killing spinors of each background are exactly the zeroes of a Dirac-like operator constructed from the Killing spinor equations.

  2. The Massive Wave Equation in Asymptotically AdS Spacetimes

    NASA Astrophysics Data System (ADS)

    Warnick, C. M.

    2013-07-01

    We consider the massive wave equation on asymptotically AdS spaces. We show that the timelike F behaves like a finite timelike boundary, on which one may impose the equivalent of Dirichlet, Neumann or Robin conditions for a range of (negative) mass parameter which includes the conformally coupled case. We demonstrate well posedness for the associated initial-boundary value problems at the H 1 level of regularity. We also prove that higher regularity may be obtained, together with an asymptotic expansion for the field near F. The proofs rely on energy methods, tailored to the modified energy introduced by Breitenlohner and Freedman. We do not assume the spacetime is stationary, nor that the wave equation separates.

  3. On jordanian deformations of AdS5 and supergravity

    NASA Astrophysics Data System (ADS)

    Hoare, Ben; van Tongeren, Stijn J.

    2016-10-01

    We consider various homogeneous Yang-Baxter deformations of the {{AdS}}5× {{{S}}}5 superstring that can be obtained from the η-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the η-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which implies that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which do correspond to supergravity solutions.

  4. 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}} )}}}}.

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. Effects of enteral and parenteral feeding of malnourished rats on body composition.

    PubMed

    Kudsk, K A; Stone, J M; Carpenter, G; Sheldon, G F

    1982-11-01

    Many studies have reported similar weight gains and nitrogen balance in groups of well-nourished animals fed either orally or intravenously, but none have investigated the effects on malnourished animals. After protein depleting for 14 days, rats were refed with a D25-4.25% amino acid solution orally ad lib, by gastrostomy, or intravenously. IV animals gained more weight with greater body fat formation than either enteral group but had lower intestinal mass and nitrogen. Route of administration influenced substrate utilization in malnourished animals fed identical diets. We conclude that weight gain cannot be used as a comparative indicator of nitrogen retention between malnourished animals fed enterally and those fed intravenously.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. Dietary preference in dairy calves for feed ingredients high in energy and protein.

    PubMed

    Miller-Cushon, E K; Montoro, C; Ipharraguerre, I R; Bach, A

    2014-03-01

    In 3 experiments, we assessed preference of recently weaned dairy calves for (1) 8 high-energy feed types [barley meal, corn meal, corn gluten feed (CGF), oat meal, rice meal, sorghum meal, wheat meal, and wheat middlings meal]; (2) 6 high-protein feed types [corn gluten meal (CGM), wheat distillers dried grains, rapeseed meal, soybean meal (SBM), sunflower meal, and pea meal]; and (3) 4 mixtures (50:50) of the highest- and lowest-ranked high-energy and high-protein feeds, to assess whether calves maintain preference for feed ingredients that are included in a mixture. In all experiments, pairwise preference tests were conducted between all feed types (28 different pairwise preference tests in experiment 1, 15 tests in experiment 2, and 6 tests in experiment 3). Each pairwise preference test was conducted by offering ad libitum access to both feed types for 6h. All tests were repeated with 20 Holstein calves. Before this study, calves were offered milk replacer at a rate of 4 L/d and a pelleted starter feed ad libitum. After weaning at 62 d of age, each calf was involved in a pairwise preference test at 3 and 5d postweaning. A preference ratio was calculated for each calf in each test as (intake of feed type A)/(intake of feed type A + intake of feed type B). Preference for feed types was ranked across tests in each experiment using pairwise comparison charts. In experiment 1, the highest-ranked high-energy feed type was wheat meal and the lowest ranked were rice meal and CGF. In experiment 2, the highest-ranked high-protein feed type was SBM and the lowest ranked was CGM. According to the preference rankings from experiments 1 and 2, experiment 3 evaluated (50:50) mixtures of SBM + wheat meal, SBM + CGF, CGM + wheat meal, and CGM + CGF. The mixture of SBM + wheat meal was highest ranked, CGM + CGF was lowest ranked, and the mixtures containing one high-ranked and one low-ranked feed ingredient (SBM + CGF and CGM + wheat meal) were ranked equally. The results of

  17. 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.

  18. Breast-feeding initiation in low-income women: Role of attitudes, support, and perceived control.

    PubMed

    Khoury, Amal J; Moazzem, S Wakerul; Jarjoura, Chad M; Carothers, Cathy; Hinton, Agnes

    2005-01-01

    Despite the documented health and emotional benefits of breast-feeding to women and children, breast-feeding rates are low among subgroups of women. In this study, we examine factors associated with breast-feeding initiation in low-income women, including Theory of Planned Behavior measures of attitude, support, and perceived control, as well as sociodemographic characteristics. A mail survey, with telephone follow-up, of 733 postpartum Medicaid beneficiaries in Mississippi was conducted in 2000. The breast-feeding initiation rate in this population was 38%. Women who were older, white, non-Hispanic, college-educated, married, not certified for the Supplemental Nutrition Program for Women, Infants, and Children, and not working full-time were more likely to breast-feed than formula-feed at hospital discharge. Attitudes regarding benefits and barriers to breast-feeding, as well as health care system and social support, were associated with breast-feeding initiation at the multivariate level. Adding the health care system support variables to the regression model, and specifically support from lactation specialists and hospital nurses, explained the association between breast-feeding initiation and women's perceived control over the time and social constraints barriers to breast-feeding. The findings support the need for health care system interventions, family interventions, and public health education campaigns to promote breast-feeding in low-income women.

  19. [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.

  20. The metabolic effects of feeding and fasting in beluga Huso huso.

    PubMed

    Falahatkar, Bahram

    2012-12-01

    A six week-study was conducted to determine the effect of starvation and feeding on growth, hematology and biochemical variables in sub-yearling beluga. Fish were placed on six feeding strategies: i) starved condition for 6 weeks, ii) a 2-week starvation, 2-week feeding and 2-week starvation, iii) a 2-week feeding, 2-week starvation and 2-week feeding, iv) a 3-week starvation followed by a 3-week feeding, v) a 3-week feeding with following 3-week starvation, and vi) fed throughout the 6 weeks. After 6 weeks, hematology, triacylglycerol, cholesterol, total protein, HSI, VSI, crude fat in muscle, final weight, feed conversion, specific growth rate, and condition factor were significantly affected by feeding strategies. The results suggested that most of the growth and physiological variables responded to a short period of starvation or re-feeding. These findings indicated that beluga could partially recover in weight and some physiological indices from periods of starvation when provided subsequently ad libitum feeding.