Science.gov

Sample records for ad libitum al

  1. Soda consumption during ad libitum food intake predicts weight change.

    PubMed

    Bundrick, Sarah C; Thearle, Marie S; Venti, Colleen A; Krakoff, Jonathan; Votruba, Susanne B

    2014-03-01

    Soda consumption may contribute to weight gain over time. Objective data were used to determine whether soda consumption predicts weight gain or changes in glucose regulation over time. Subjects without diabetes (128 men, 75 women; mean age 34.3±8.9 years; mean body mass index 32.5±7.4; mean percentage body fat 31.6%±8.6%) self-selected their food from an ad libitum vending machine system for 3 days. Mean daily energy intake was calculated from food weight. Energy consumed from soda was recorded as were food choices that were low in fat (<20% of calories from fat) or high in simple sugars (>30%). Food choices were expressed as percentage of daily energy intake. A subset of 85 subjects had measurement of follow-up weights and oral glucose tolerance (57 men, 28 women; mean follow-up time=2.5±2.1 years, range 6 months to 9.9 years). Energy consumed from soda was negatively related to age (r=-0.27, P=0.0001) and choosing low-fat foods (r=-0.35, P<0.0001), but positively associated with choosing solid foods high in simple sugars (r=0.45, P<0.0001) and overall average daily energy intake (r=0.46, P<0.0001). Energy intake from food alone did not differ between individuals who did and did not consume beverage calories (P=0.11). Total daily energy intake had no relationship with change in weight (P=0.29) or change in glucose regulation (P=0.38) over time. However, energy consumed from soda correlated with change in weight (r=0.21, P=0.04). This relationship was unchanged after adjusting for follow-up time and initial weight. Soda consumption is a marker for excess energy consumption and is associated with weight gain.

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

    PubMed

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

    2016-09-01

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

  3. Oral fluid cannabinoids in chronic frequent cannabis smokers during ad libitum cannabis smoking.

    PubMed

    Lee, Dayong; Vandrey, Ryan; Mendu, Damodara R; Murray, Jeannie A; Barnes, Allan J; Huestis, Marilyn A

    2015-06-01

    Oral fluid (OF) offers a simple, non-invasive, directly observable sample collection for clinical and forensic drug testing. Given that chronic cannabis smokers often engage in drug administration multiple times daily, evaluating OF cannabinoid pharmacokinetics during ad libitum smoking is important for practical development of analytical methods and informed interpretation of test results. Eleven cannabis smokers resided in a closed research unit for 51 days, and underwent four, 5-day oral delta-9-tetrahydrocannabinol (THC) treatments. Each medication period was separated by 9 days of ad libitum cannabis smoking from 12:00 to 23:00 h daily. Ten OF samples were collected from 9:00-22:00 h on each of the last ad libitum smoking days (Study Days 4, 18, 32, and 46). As the number of cannabis cigarettes smoked increased over the study days, OF THC, cannabinol (CBN), and 11-nor-9-carboxy-THC (THCCOOH) also increased with a significant effect of time since last smoking (Δtime; range, 0.0-17.4 h) and ≥88% detection rates; concentrations on Day 4 were significantly lower than those on Days 32 and 46 but not Day 18. Within 30 min of smoking, median THC, CBN, and THCCOOH concentrations were 689 µg/L, 116 µg/L, and 147 ng/L, respectively, decreasing to 19.4 µg/L, 2.4 µg/L, and 87.6 ng/L after 10 h. Cannabidiol and 11-hydroxy-THC showed overall lower detection rates of 29 and 8.6%, respectively. Cannabinoid disposition in OF was highly influenced by Δtime and composition of smoked cannabis. Furthermore, cannabinoid OF concentrations increased over ad libitum smoking days, in parallel with increased cannabis self-administration, possibly reflecting development of increased cannabis tolerance. PMID:25220020

  4. Oral fluid cannabinoids in chronic frequent cannabis smokers during ad libitum cannabis smoking.

    PubMed

    Lee, Dayong; Vandrey, Ryan; Mendu, Damodara R; Murray, Jeannie A; Barnes, Allan J; Huestis, Marilyn A

    2015-06-01

    Oral fluid (OF) offers a simple, non-invasive, directly observable sample collection for clinical and forensic drug testing. Given that chronic cannabis smokers often engage in drug administration multiple times daily, evaluating OF cannabinoid pharmacokinetics during ad libitum smoking is important for practical development of analytical methods and informed interpretation of test results. Eleven cannabis smokers resided in a closed research unit for 51 days, and underwent four, 5-day oral delta-9-tetrahydrocannabinol (THC) treatments. Each medication period was separated by 9 days of ad libitum cannabis smoking from 12:00 to 23:00 h daily. Ten OF samples were collected from 9:00-22:00 h on each of the last ad libitum smoking days (Study Days 4, 18, 32, and 46). As the number of cannabis cigarettes smoked increased over the study days, OF THC, cannabinol (CBN), and 11-nor-9-carboxy-THC (THCCOOH) also increased with a significant effect of time since last smoking (Δtime; range, 0.0-17.4 h) and ≥88% detection rates; concentrations on Day 4 were significantly lower than those on Days 32 and 46 but not Day 18. Within 30 min of smoking, median THC, CBN, and THCCOOH concentrations were 689 µg/L, 116 µg/L, and 147 ng/L, respectively, decreasing to 19.4 µg/L, 2.4 µg/L, and 87.6 ng/L after 10 h. Cannabidiol and 11-hydroxy-THC showed overall lower detection rates of 29 and 8.6%, respectively. Cannabinoid disposition in OF was highly influenced by Δtime and composition of smoked cannabis. Furthermore, cannabinoid OF concentrations increased over ad libitum smoking days, in parallel with increased cannabis self-administration, possibly reflecting development of increased cannabis tolerance.

  5. Brisk walking reduces ad libitum snacking in regular chocolate eaters during a workplace simulation.

    PubMed

    Oh, Hwajung; Taylor, Adrian H

    2012-02-01

    Workplace snacking can contribute to obesity. Exercise reduces chocolate cravings but effects on chocolate consumption are unknown. This study investigated the effect of brief exercise on ad libitum consumption during breaks in a computerised task. Seventy-eight regular chocolate eaters, age: 24.90±8.15 years, BMI: 23.56±3.78 kg/m(2) abstained for 2 days. They were randomly assigned to one of four conditions, in a 2 × 2 factorial design, involving either a 15 min brisk walk or quiet rest, and then computerised Stroop tasks with low or high demanding conditions, in three 180 s blocks with a 90 s interval. Throughout, a pre-weighed bowl of chocolates was available for ad libitum eating. A two-way ANOVA revealed no interaction effect of exercise and stress on total chocolate consumption, or main effect of stress, but a main effect of exercise [F(1, 74)=7.12, p<.01]. Mean (SD) chocolate consumption was less (t(73.5)=2.69, 95% CI for difference 3.4-22.9, ES=0.61) for the exercise (15.6 g) than control (28.8 g) group. Exercise also increased affective activation, but there was no mediating effect of change in affect on chocolate consumption. A brief walk may help to reduce ad libitum snacking in regular chocolate eaters. PMID:22100187

  6. Walking reduces cue-elicited cigarette cravings and withdrawal symptoms, and delays ad libitum smoking.

    PubMed

    Taylor, Adrian; Katomeri, Magdalena

    2007-11-01

    Stress and exposure to smoking cues influence smoking cravings and behavior. Exercise appears to reduce cigarette cravings and withdrawal symptoms, but no study has investigated the effects of exercise on cue-elicited cravings and withdrawal symptoms, or ad libitum smoking behavior. In this study, 60 regular smokers, invited by public advertisements, were assessed at baseline following 2 hr of abstinence, and randomized to a 15-min brisk walk or passive condition. Both groups then completed three tasks (Stroop color-word interference task, speech task, and handling a lit cigarette). Cravings were assessed with two single items, and withdrawal symptoms were assessed using the seven-item Mood and Physical Symptoms Scale. After the laboratory session, ad libitum smoking was determined from the subject's cell phone text message. Exercise (mean heart rate reserve = 24%) attenuated increases in strength of desire to smoke, tension, poor concentration, and stress, in response to a lit cigarette, but had minimal effects on increases in cravings and withdrawal symptoms in response to the stressors. Absolute levels of cravings and withdrawal symptoms were reduced during and following exercise. Exercisers engaged in ad libitum smoking a net 57 min (CI = 31-83) later than those in the passive condition. A 15-min brisk walk not only reduced cigarette cravings and withdrawal symptoms but also could attenuate increases in cue-elicited cravings and withdrawal symptoms, and increase the time between cigarettes smoked.

  7. Caloric beverages consumed freely at meal-time add calories to an ad libitum meal.

    PubMed

    Panahi, Shirin; El Khoury, Dalia; Luhovyy, Bohdan L; Goff, H Douglas; Anderson, G Harvey

    2013-06-01

    The objective was to compare the effects of ad libitum consumption of commonly consumed meal-time beverages on energy and fluid intakes and post-meal average subjective appetite and blood glucose in healthy adults. In a randomized controlled design, 29 males and females consumed to satiation an ad libitum pizza meal with one of five beverages in unlimited amount including water (0 kcal), 1% milk (44 kcal/100 ml), regular cola (44 kcal/100 ml), orange juice (44 kcal/100 ml) and diet cola (0 kcal). Food and fluid intakes were measured at the meal. Average subjective appetite and blood glucose were measured before and for 2h after the meal. Although energy intake from pizza was similar among all beverage treatments, the amount of fluid consumed (g) varied among the beverages with intake of orange juice higher than regular and diet cola, but not different from water or milk. Meal-time ingestion of caloric beverages, milk, orange juice and regular cola, led to higher total meal-time energy intakes compared to either water or diet cola. Post-meal blood glucose area under the curve (AUC) was lower after milk than after meals with water, orange juice and regular cola and post-meal average subjective appetite AUC was lower after milk than after meals with water. Meal intakes of nutrients including protein, calcium, phosphorus, zinc, vitamins B12, A and D were higher at the meal with milk compared to the other beverages. Thus, caloric beverages consumed ad libitum during a meal add to total meal-time energy intake, but 1% milk favors a lower post-meal blood glucose and average subjective appetite score and adds to nutrient intake.

  8. Effect of exercise on cigarette cravings and ad libitum smoking following concurrent stressors.

    PubMed

    Fong, Angela J; De Jesus, Stefanie; Bray, Steven R; Prapavessis, Harry

    2014-10-01

    The health consequences of smoking are well documented, yet quit rates are modest. While exercise has supported decreased cravings and withdrawal symptoms in temporarily abstinent smokers, it has yet to be applied when smokers are experiencing concurrent stressors. This study examined the effect of an acute bout of moderate intensity exercise on cravings (primary outcome) and ad libitum smoking (secondary outcome) following concurrent stressors (i.e., temporary abstinence and environmental manipulation-Stroop cognitive task+cue-elicited smoking stimuli). Twenty-five smokers (>10cig/day; Mean age=37.4years) were randomized into either exercise (n=12) or passive sitting conditions. A repeated measure (RM) ANOVA showed that psychological withdrawal symptoms (a measure of distress) were significantly exacerbated after temporary abstinence and then again after the environmental manipulation for all participants (p<.0001, η(2)=.50). Furthermore, a treatment by time RM ANOVA revealed decreases in psychological withdrawal symptoms for only the exercise condition (p<.001, η(2)=.42). A treatment by time RM ANOVA also revealed craving reductions for only the exercise condition (p<.0001, η(2)=.82). Exercise had no effect on ad libitum smoking. This is the first study to use a lab-based scenario with high ecological validity to show that an acute bout of exercise can reduce cravings following concurrent stressors. Future work is now needed where momentary assessment is used in people's natural environment to examine changes in cigarette cravings following acute bouts of exercise. PMID:24971700

  9. Effect of exercise on cigarette cravings and ad libitum smoking following concurrent stressors.

    PubMed

    Fong, Angela J; De Jesus, Stefanie; Bray, Steven R; Prapavessis, Harry

    2014-10-01

    The health consequences of smoking are well documented, yet quit rates are modest. While exercise has supported decreased cravings and withdrawal symptoms in temporarily abstinent smokers, it has yet to be applied when smokers are experiencing concurrent stressors. This study examined the effect of an acute bout of moderate intensity exercise on cravings (primary outcome) and ad libitum smoking (secondary outcome) following concurrent stressors (i.e., temporary abstinence and environmental manipulation-Stroop cognitive task+cue-elicited smoking stimuli). Twenty-five smokers (>10cig/day; Mean age=37.4years) were randomized into either exercise (n=12) or passive sitting conditions. A repeated measure (RM) ANOVA showed that psychological withdrawal symptoms (a measure of distress) were significantly exacerbated after temporary abstinence and then again after the environmental manipulation for all participants (p<.0001, η(2)=.50). Furthermore, a treatment by time RM ANOVA revealed decreases in psychological withdrawal symptoms for only the exercise condition (p<.001, η(2)=.42). A treatment by time RM ANOVA also revealed craving reductions for only the exercise condition (p<.0001, η(2)=.82). Exercise had no effect on ad libitum smoking. This is the first study to use a lab-based scenario with high ecological validity to show that an acute bout of exercise can reduce cravings following concurrent stressors. Future work is now needed where momentary assessment is used in people's natural environment to examine changes in cigarette cravings following acute bouts of exercise.

  10. Plasma Cannabinoid Pharmacokinetics After Controlled Smoking and Ad libitum Cannabis Smoking in Chronic Frequent Users.

    PubMed

    Lee, Dayong; Bergamaschi, Mateus M; Milman, Garry; Barnes, Allan J; Queiroz, Regina H C; Vandrey, Ryan; Huestis, Marilyn A

    2015-10-01

    More Americans are dependent on cannabis than any other illicit drug. The main analytes for cannabis testing include the primary psychoactive constituent, Δ(9)-tetrahydrocannabinol (THC), equipotent 11-hydroxy-THC (11-OH-THC) and inactive 11-nor-9-carboxy-THC (THCCOOH). Eleven adult chronic frequent cannabis smokers resided on a closed research unit with unlimited access to 5.9% THC cannabis cigarettes from 12:00 to 23:00 during two ad libitum smoking phases, followed by a 5-day abstinence period in seven participants. A single cigarette was smoked under controlled topography on the last day of the smoking and abstinence phases. Plasma cannabinoids were quantified by two-dimensional gas chromatography-mass spectrometry. Median plasma maximum concentrations (Cmax) were 28.3 (THC), 3.9 (11-OH-THC) and 47.0 μg/L (THCCOOH) 0.5 h after controlled single cannabis smoking. Median Cmax 0.2-0.5 h after ad libitum smoking was higher for all analytes: 83.5 (THC), 14.2 (11-OH-THC) and 155 μg/L (THCCOOH). All 11 participants' plasma samples were THC and THCCOOH-positive, 58.3% had THC ≥5 μg/L and 79.2% were 11-OH-THC-positive 8.1-14 h after last cannabis smoking. Cannabinoid detection rates in seven participants 106-112 h (4-5 days) after last smoking were 92.9 (THC), 35.7 (11-OH-THC) and 100% (THCCOOH), with limits of quantification of 0.5 μg/L for THC and THCCOOH, and 1.0 μg/L for 11-OH-THC. These data greatly expand prior research findings on cannabinoid excretion profiles in chronic frequent cannabis smokers during ad libitum smoking. Smoking multiple cannabis cigarettes led to higher Cmax and AUC compared with smoking a single cigarette. The chronic frequent cannabis smokers exhibited extended detection windows for plasma cannabinoids, reflecting a large cannabinoid body burden. PMID:26378131

  11. Plasma Cannabinoid Pharmacokinetics After Controlled Smoking and Ad libitum Cannabis Smoking in Chronic Frequent Users

    PubMed Central

    Lee, Dayong; Bergamaschi, Mateus M.; Milman, Garry; Barnes, Allan J.; Queiroz, Regina H.C.; Vandrey, Ryan; Huestis, Marilyn A.

    2015-01-01

    More Americans are dependent on cannabis than any other illicit drug. The main analytes for cannabis testing include the primary psychoactive constituent, Δ9-tetrahydrocannabinol (THC), equipotent 11-hydroxy-THC (11-OH-THC) and inactive 11-nor-9-carboxy-THC (THCCOOH). Eleven adult chronic frequent cannabis smokers resided on a closed research unit with unlimited access to 5.9% THC cannabis cigarettes from 12:00 to 23:00 during two ad libitum smoking phases, followed by a 5-day abstinence period in seven participants. A single cigarette was smoked under controlled topography on the last day of the smoking and abstinence phases. Plasma cannabinoids were quantified by two-dimensional gas chromatography–mass spectrometry. Median plasma maximum concentrations (Cmax) were 28.3 (THC), 3.9 (11-OH-THC) and 47.0 μg/L (THCCOOH) 0.5 h after controlled single cannabis smoking. Median Cmax 0.2–0.5 h after ad libitum smoking was higher for all analytes: 83.5 (THC), 14.2 (11-OH-THC) and 155 μg/L (THCCOOH). All 11 participants' plasma samples were THC and THCCOOH-positive, 58.3% had THC ≥5 μg/L and 79.2% were 11-OH-THC-positive 8.1–14 h after last cannabis smoking. Cannabinoid detection rates in seven participants 106–112 h (4–5 days) after last smoking were 92.9 (THC), 35.7 (11-OH-THC) and 100% (THCCOOH), with limits of quantification of 0.5 μg/L for THC and THCCOOH, and 1.0 μg/L for 11-OH-THC. These data greatly expand prior research findings on cannabinoid excretion profiles in chronic frequent cannabis smokers during ad libitum smoking. Smoking multiple cannabis cigarettes led to higher Cmax and AUC compared with smoking a single cigarette. The chronic frequent cannabis smokers exhibited extended detection windows for plasma cannabinoids, reflecting a large cannabinoid body burden. PMID:26378131

  12. Plasma Cannabinoid Pharmacokinetics After Controlled Smoking and Ad libitum Cannabis Smoking in Chronic Frequent Users.

    PubMed

    Lee, Dayong; Bergamaschi, Mateus M; Milman, Garry; Barnes, Allan J; Queiroz, Regina H C; Vandrey, Ryan; Huestis, Marilyn A

    2015-10-01

    More Americans are dependent on cannabis than any other illicit drug. The main analytes for cannabis testing include the primary psychoactive constituent, Δ(9)-tetrahydrocannabinol (THC), equipotent 11-hydroxy-THC (11-OH-THC) and inactive 11-nor-9-carboxy-THC (THCCOOH). Eleven adult chronic frequent cannabis smokers resided on a closed research unit with unlimited access to 5.9% THC cannabis cigarettes from 12:00 to 23:00 during two ad libitum smoking phases, followed by a 5-day abstinence period in seven participants. A single cigarette was smoked under controlled topography on the last day of the smoking and abstinence phases. Plasma cannabinoids were quantified by two-dimensional gas chromatography-mass spectrometry. Median plasma maximum concentrations (Cmax) were 28.3 (THC), 3.9 (11-OH-THC) and 47.0 μg/L (THCCOOH) 0.5 h after controlled single cannabis smoking. Median Cmax 0.2-0.5 h after ad libitum smoking was higher for all analytes: 83.5 (THC), 14.2 (11-OH-THC) and 155 μg/L (THCCOOH). All 11 participants' plasma samples were THC and THCCOOH-positive, 58.3% had THC ≥5 μg/L and 79.2% were 11-OH-THC-positive 8.1-14 h after last cannabis smoking. Cannabinoid detection rates in seven participants 106-112 h (4-5 days) after last smoking were 92.9 (THC), 35.7 (11-OH-THC) and 100% (THCCOOH), with limits of quantification of 0.5 μg/L for THC and THCCOOH, and 1.0 μg/L for 11-OH-THC. These data greatly expand prior research findings on cannabinoid excretion profiles in chronic frequent cannabis smokers during ad libitum smoking. Smoking multiple cannabis cigarettes led to higher Cmax and AUC compared with smoking a single cigarette. The chronic frequent cannabis smokers exhibited extended detection windows for plasma cannabinoids, reflecting a large cannabinoid body burden.

  13. Spending one's time: the hedonic principle in ad libitum viewing of pictures.

    PubMed

    Kron, Assaf; Pilkiw, Maryna; Goldstein, Ariel; Lee, Daniel H; Gardhouse, Katherine; Anderson, Adam K

    2014-12-01

    The hedonic principle maintains that humans strive to maximize pleasant feelings and avoid unpleasant feelings. Surprisingly, and contrary to hedonic logic, previous experiments have demonstrated a relationship between picture viewing time and arousal (activation) but not with valence (pleasure vs. displeasure), suggesting that arousal rather than the hedonic principle accounts for how individuals choose to spend their time. In 2 experiments we investigated the arousal and hedonic principles underlying viewing time behavior while controlling for familiarity with stimuli, picture complexity, and demand characteristics. Under ad libitum conditions of picture viewing, we found strong relationships between viewing time, valence, and facial corrugator electomyographic (EMG) activity with familiar but not novel pictures. Viewing time of novel stimuli was largely associated with arousal and visual complexity. We conclude that only after initial information about the stimulus is gathered, where we choose to spend our time is guided by the hedonic principle.

  14. Ad-libitum drinking and performance during a 40-km cycling time trial in the heat.

    PubMed

    Berkulo, Meriam A R; Bol, Susan; Levels, Koen; Lamberts, Robert P; Daanen, Hein A M; Noakes, Timothy D

    2016-01-01

    The aim of this study was to investigate if drinking ad-libitum can counteract potential negative effects of a hypohydrated start caused by fluid restriction during a 40-km time trial (TT) in the heat. Twelve trained males performed one 40-km cycling TT euhydrated (EU: no water during the TT) and two 40-km cycling TTs hypohydrated. During one hypohydrated trial no fluid was ingested (HYPO), during the other trial ad-libitum water ingestion was allowed (FLUID). Ambient temperature was 35.2 ± 0.2 °C, relative humidity 51 ± 3% and airflow 7 m·s(-1). Body mass (BM) was determined at the start of the test, and before and after the TT. During the TT, power output, heart rate (HR), gastrointestinal temperature, mean skin temperature, rating of perceived exertion (RPE), thermal sensation, thermal comfort and thirst sensation were measured. Prior to the start of the TT, BM was 1.2% lower in HYPO and FLUID compared to EU. During the TT, BM loss in FLUID was lower compared to EU and HYPO (1.0 ± 0.8%, 2.7 ± 0.2% and 2.6 ± 0.3%, respectively). Hydration status had no effect on power output (EU: 223 ± 32 W, HYPO: 217 ± 39 W, FLUID: 224 ± 35 W), HR, gastrointestinal temperature, mean skin temperature, RPE, thermal sensation and thermal comfort. Thirst sensation was higher in HYPO than in EU and FLUID. It was concluded that hypohydration did not adversely affect performance during a 40-km cycling TT in the heat. Therefore, whether or not participants consumed fluid during exercise did not influence their TT performance.

  15. Comparison of behaviour, performance and mortality in restricted and ad libitum-fed growing rabbits.

    PubMed

    Dalmau, A; Abdel-Khalek, A M; Ramon, J; Piles, M; Sanchez, J P; Velarde, A; Rafel, O

    2015-07-01

    The objective of this study was to determine whether rabbits fed in a restricted regimen (75%) showed increased competition for feeding, drinking and use of specific areas of the cages as compared with those provided feed ad libitum. This evaluation was carried out by measuring their space utilisation in the cage, the incidence of agonistic behaviour and rates of mortality. In total, 504 rabbits between 31 and 66 days of age were used in this study. A total of 200 heavy-weight rabbits and 56 light-weight rabbits were randomly housed in 32 cages, each cage containing eight rabbits: 25 cages housing heavy rabbits and seven cages housing the light-weight ones. They were all fed ad libitum (AD). In addition, a total of 208 heavy-weight rabbits and 40 light-weight rabbits were randomly housed in 31 cages, each of them containing eight rabbits: 26 cages housing heavy weight rabbits and five cages housing light-weight ones. They were all fed a restricted diet (R) regimen. The restriction was calculated to be 75% of the feed consumed by the AD group. The total space available in the cage was 3252 cm(2), with a stocking density of 24.6 animals/m(2). Animals between 32 and 60 days of age from 20 different cages were observed nine times per week (morning or afternoon) by means of scan and focal sampling by one observer. During each period, cages were assessed for 5 min, registering every minute the position of all the animals in relation to Area A (feeder), Area B (central part) or Area C (back and drinker area). The incidence of agonistic behaviour such as displacement, biting and jumping on each other was also assessed. Performance variables such as daily gain and feed conversion ratio, in addition to general health status and mortality rates, were recorded for all rabbits. When the rabbits were under restricted feeding, the competition for feed and drink increased with clear signs of agonistic behaviour such as biting, displacement and animals jumping on top of each other

  16. Comparison of behaviour, performance and mortality in restricted and ad libitum-fed growing rabbits.

    PubMed

    Dalmau, A; Abdel-Khalek, A M; Ramon, J; Piles, M; Sanchez, J P; Velarde, A; Rafel, O

    2015-07-01

    The objective of this study was to determine whether rabbits fed in a restricted regimen (75%) showed increased competition for feeding, drinking and use of specific areas of the cages as compared with those provided feed ad libitum. This evaluation was carried out by measuring their space utilisation in the cage, the incidence of agonistic behaviour and rates of mortality. In total, 504 rabbits between 31 and 66 days of age were used in this study. A total of 200 heavy-weight rabbits and 56 light-weight rabbits were randomly housed in 32 cages, each cage containing eight rabbits: 25 cages housing heavy rabbits and seven cages housing the light-weight ones. They were all fed ad libitum (AD). In addition, a total of 208 heavy-weight rabbits and 40 light-weight rabbits were randomly housed in 31 cages, each of them containing eight rabbits: 26 cages housing heavy weight rabbits and five cages housing light-weight ones. They were all fed a restricted diet (R) regimen. The restriction was calculated to be 75% of the feed consumed by the AD group. The total space available in the cage was 3252 cm(2), with a stocking density of 24.6 animals/m(2). Animals between 32 and 60 days of age from 20 different cages were observed nine times per week (morning or afternoon) by means of scan and focal sampling by one observer. During each period, cages were assessed for 5 min, registering every minute the position of all the animals in relation to Area A (feeder), Area B (central part) or Area C (back and drinker area). The incidence of agonistic behaviour such as displacement, biting and jumping on each other was also assessed. Performance variables such as daily gain and feed conversion ratio, in addition to general health status and mortality rates, were recorded for all rabbits. When the rabbits were under restricted feeding, the competition for feed and drink increased with clear signs of agonistic behaviour such as biting, displacement and animals jumping on top of each other

  17. Evidence for hepatic involvement in control of ad libitum food intake in rats.

    PubMed

    Friedman, M I; Sawchenko, P E

    1984-07-01

    Sectioning the hepatic branch of the anterior abdominal vagal trunk attenuated but did not abolish the normal nocturnal bias in the day-night distribution of food intake in female rats. Neither total daily food intake nor body weight was affected by hepatic vagotomy. This effect appeared to be specific to the hepatic branch of the nerve because sectioning the remaining (gastric and celiac) abdominal vagal branches did not influence daily feeding rhythms and appeared to be specific to feeding behavior, because the day-night rhythms of drinking behavior and wheel-running activity were not affected by hepatic vagotomy. In male rats, hepatic vagotomy also produced an increase in daytime food consumption but without commensurate reduction in nighttime eating. As a result, male rats with hepatic vagotomy displayed a modest chronic hyperphagia and body weight gain, which was associated primarily with increased linear growth. The effect of nerve section on daytime food intake was expressed quite rapidly. Daytime food intake increased within 8 h after hepatic vagotomy, which was produced at light onset by pulling on a previously implanted suture. Collectively, these results demonstrate that hepatic vagotomy changes daily feeding rhythms and suggest that the liver and perhaps its vagal innervation are involved in the control of ad libitum eating behavior.

  18. Predicting ad libitum dry matter intake and yields of Jersey cows.

    PubMed

    Holter, J B; West, J W; McGilliard, M L; Pell, A N

    1996-05-01

    Two data files were used that contained weekly mean values for ad libitum DMI of lactating Jersey cows along with appropriate cow, ration, and environmental traits for predicting DMI. One data file (n = 666) was used to develop prediction equations for DMI because that file represented a number of separate experiments and contained more diversity in potential predictors, especially those related to ration, such as forage type. The other data file (n = 1613) was used primarily to verify these equations. Milk protein yield displaced 4% FCM output as a prediction variable and improved the R2 by several units but was not used in the final equations, however, for the sake of simplicity. All equations contained adjustments for the effects of heat stress, parity (1 vs. > 1), DIM > 15, BW, use of recombinant bST, and other significant independent variables. Equations were developed to predict DMI of cows fed individually or in groups and to predict daily yields of 4% FCM and milk protein; equations accounted for 0.69, 0.74, 0.81, and 0.76 of the variation in the dependent variables with standard deviations of 1.7, 1.6, 2.7, and 0.084 kg/ d, respectively. These equations should be applied to the development of software for computerized dairy ration balancing.

  19. Food intake and blood glucose in normal and diabetic cats fed ad libitum.

    PubMed

    Martin, G J; Rand, J S

    1999-12-01

    Ten diabetic cats were studied at intervals for up to 12 months with twice-daily insulin injections. Ten clinically healthy cats were also studied. Diets fed were based on the individual cat's performance, using mainly commercial dry or canned cat foods and fresh meat. In most cases more than one food was offered. Food was given fresh twice daily, and the cats allowed to eat ad libitum. The food intake and blood glucose were measured every 2 h in diabetic cats after insulin injection and in diabetic and normal cats without insulin injections. Food was quantified by the energy consumed (kJ ME), crude protein (g), crude fat (g), and carbohydrate (g). The blood glucose in 10 diabetic cats was measured for 2 h following a 20-min meal. Both diabetic cats and normal cats showed similar patterns of eating, with a higher food intake in the 2 h after fresh food was placed. Both groups of cats ate multiple small meals spread through the day and night. There was little or no correlation between the blood glucose and the amount of food consumed over the previous 2-h period, in insulin- or non-insulin-treated diabetic cats, or in normal cats. An overnight fast did not significantly alter morning blood glucose in diabetic cats. No demonstrable appetite stimulation occurred following an occurrence of low blood glucose; however, recorded incidences were few. No post-prandial hyperglycaemia was seen in the 10 diabetic cats during a 2-h period following the ingestion of typical cat foods.

  20. Effects of acute exercise on appetite hormones and ad libitum energy intake in men and women.

    PubMed

    Hagobian, Todd Alan; Yamashiro, Megan; Hinkel-Lipsker, Jake; Streder, Katherine; Evero, Nero; Hackney, Terry

    2013-01-01

    Acute exercise suppresses relative energy intake; however, it remains unclear whether this occurs in both men and women exposed to the same relative exercise treatment. Eleven healthy men (22 ± 2 years; 16% ± 6% body fat (BF); 26 ± 4 body mass index (BMI); 42.9 ± 6.5 mL·kg(-1)·min(-1) peak oxygen consumption ([Formula: see text]O(2peak))) and 10 healthy women (21 ± 2 years; 24 ± 2 BMI; 23% ± 3% BF; 39.9 ± 5.5 mL·kg(-1)·min(-1) [Formula: see text]O(2peak)) rested for 60 min or exercised on a cycle ergometer at 70% [Formula: see text]O(2peak) until 30% of total daily energy expenditure was expended (men, expenditure = 975 ± 195 kcal in 82 ± 13 min; women, expenditure = 713 ± 86 kcal in 84 ± 17 min) in a counterbalanced, crossover fashion. Appetite hormones and appetite ratings were assessed in response to each condition. Forty minutes after both conditions, ad libitum total and relative energy intake (energy intake minus energy cost of exercise) were assessed at a buffet meal. There was no significant sex or condition effect in appetite hormones (PYY(3-36), acylated ghrelin, insulin) and appetite ratings (hunger, satisfaction, fullness). Total energy intake in men was significantly higher (P < 0.05) in exercise and rest conditions (1648 ± 950, 1216 ± 633 kcal, respectively) compared with women (591 ± 183, 590 ± 231 kcal, respectively). Relative energy intake was significantly lower (P < 0.05) after exercise compared with rest in men (672 ± 827, 1133 ± 619 kcal, respectively) and women (-121 ± 243, 530 ± 233 kcal, respectively). These data highlight the effectiveness of acute exercise to suppress relative energy intake regardless of sex.

  1. Sleep duration modifies effects of free ad libitum school meals on adiposity and blood pressure.

    PubMed

    Hjorth, Mads F; Sjödin, Anders; Dalskov, Stine-Mathilde; Damsgaard, Camilla Trab; Michaelsen, Kim F; Biltoft-Jensen, Anja; Andersen, Rikke; Ritz, Christian; Chaput, Jean-Philippe; Astrup, Arne

    2016-01-01

    Insufficient sleep can potentially affect both energy intake and energy expenditure, resulting in obesity and reduced cardiometabolic health. The objective of the study was to investigate if habitual sleep duration of 8- to 11-year-olds modifies the effect of free ad libitum school meals on cardiometabolic markers, body composition, dietary intake, and physical activity. For 2 consecutive 3-month periods, this cluster-randomized, controlled, cross-over trial provided 530 children with school meals or usual lunch brought from home. Dietary intake, activity, and sleep were measured simultaneously for 7 consecutive days using dietary records and accelerometers. Short- and long-sleeping children were defined as lower and upper tertile of sleep duration. Body composition, blood pressure, blood lipids, and homeostatic model assessment of insulin resistance (HOMAIR) were measured/calculated. Overall, school meals compared with lunch from home had positive effects on physical activity and blood pressure in long-sleeping children and negative effects on body fat in short-sleeping children. Short-sleeping children increased fat mass compared with long-sleeping children by 0.21 (95% confidence interval 0.03-0.38) kg, android fat mass by 0.02 (0.001-0.04) kg, waist circumference by 0.73 (0.23-1.24) cm, blood pressure by 1.5 (0.4-2.6) mm Hg, fat intake by 1.1 (0.2-2.0) percentage of energy, and decreased total physical activity by 7.2 (1.6-12.7) % (all P ≤ 0.04), while HOMAIR and blood lipids were not modified by sleep duration (all P ≥ 0.32). In conclusion, the susceptibility to increase abdominal adiposity and blood pressure when exposed to dietary changes can potentially be explained by too little sleep, which results in increased caloric intake and reduced physical activity. PMID:26647154

  2. Sleep duration modifies effects of free ad libitum school meals on adiposity and blood pressure.

    PubMed

    Hjorth, Mads F; Sjödin, Anders; Dalskov, Stine-Mathilde; Damsgaard, Camilla Trab; Michaelsen, Kim F; Biltoft-Jensen, Anja; Andersen, Rikke; Ritz, Christian; Chaput, Jean-Philippe; Astrup, Arne

    2016-01-01

    Insufficient sleep can potentially affect both energy intake and energy expenditure, resulting in obesity and reduced cardiometabolic health. The objective of the study was to investigate if habitual sleep duration of 8- to 11-year-olds modifies the effect of free ad libitum school meals on cardiometabolic markers, body composition, dietary intake, and physical activity. For 2 consecutive 3-month periods, this cluster-randomized, controlled, cross-over trial provided 530 children with school meals or usual lunch brought from home. Dietary intake, activity, and sleep were measured simultaneously for 7 consecutive days using dietary records and accelerometers. Short- and long-sleeping children were defined as lower and upper tertile of sleep duration. Body composition, blood pressure, blood lipids, and homeostatic model assessment of insulin resistance (HOMAIR) were measured/calculated. Overall, school meals compared with lunch from home had positive effects on physical activity and blood pressure in long-sleeping children and negative effects on body fat in short-sleeping children. Short-sleeping children increased fat mass compared with long-sleeping children by 0.21 (95% confidence interval 0.03-0.38) kg, android fat mass by 0.02 (0.001-0.04) kg, waist circumference by 0.73 (0.23-1.24) cm, blood pressure by 1.5 (0.4-2.6) mm Hg, fat intake by 1.1 (0.2-2.0) percentage of energy, and decreased total physical activity by 7.2 (1.6-12.7) % (all P ≤ 0.04), while HOMAIR and blood lipids were not modified by sleep duration (all P ≥ 0.32). In conclusion, the susceptibility to increase abdominal adiposity and blood pressure when exposed to dietary changes can potentially be explained by too little sleep, which results in increased caloric intake and reduced physical activity.

  3. The interdependence of glycolytic and pentose cycle intermediates in ad libitum fed rats.

    PubMed

    Casazza, J P; Veech, R L

    1986-01-15

    .0008. These data indicate the interdependence of the liver content of glycolytic intermediates and pentose cycle intermediates in ad libitum fed rats.

  4. Biomedical responses of rats to chronic exposure to dietary cadmium fed in ad libitum and equalized regimes.

    PubMed

    Cousins, R J; Squibb, K S; Feldman, S L; de Bari, A; Silbon, B L

    1977-03-01

    Forty 100 g male rats were fed, in groups of eight, either 0, 5, or 25 ppm cadmium in a purified diet for 14 wk. Three groups were fed each of the levels of cadmium on an ad libitum basis. Two other groups were fed either 0 or 5 ppm cadmium in amounts that were equalized to that consumed by the 25 ppm group fed ad libitum. Cadmium ingestion decreased daily diet consumption, weight gain, and terminal body weight. These parameters were not significantly different in rats whose diet consumption was equalized. Packed cell volume and serum iron as well as serum zinc were decreased in the rats fed 25 ppm cadmium. These effects were not related to diet intake. No major differences were observed in serum ceruloplasmin, glucose, protein, leucine aminopeptidase activity, or copper in any of the groups. Blood urea nitrogen and renal leucine aminopeptidase activity were decreased by cadmium ingestion in the rats fed ad libitum only. In contrast, serum alkaline phosphatase activity was elevated by cadmium in the equalized-intake groups only. Cadmium and zinc concentrations were elevated and the iron concentration was decreased in the kidney, liver, and intestinal mucosa of the cadmium-fed rats irrespective of level of diet consumption. The increased uptake of cadmium in these tissues was coincident with the increased content of the cadmium-binding protein, metallothionein, in the cytosol fraction. The results indicate that some parameters of chronic cadmium toxicity are associated with diet consumption whereas others are not.

  5. On-demand antimicrobial release from a temperature-sensitive polymer - comparison with ad libitum release from central venous catheters.

    PubMed

    Sjollema, Jelmer; Dijkstra, Rene J B; Abeln, Caroline; van der Mei, Henny C; van Asseldonk, Dirk; Busscher, Henk J

    2014-08-28

    Antimicrobial releasing biomaterial coatings have found application for instance in the fixation of orthopedic joint prostheses and central venous catheters. Most frequently, the release kinetics is such that antimicrobially-effective concentrations are only reached within the first days to weeks after implantation, leaving no local antimicrobial release available when a biomaterial-associated infection occurs later. Here we compare the ad libitum release of chlorhexidine and silver-sulfadiazine from a central venous catheter with their release from a new, on-demand release coating consisting of a temperature-sensitive copolymer of styrene and n-butyl (meth)acrylate. The copolymer can be loaded with an antimicrobial, which is released when the temperature is raised above its glass transition temperature. Ad libitum release of chlorhexidine and silver-sulfadiazine from a commercially-purchased catheter and associated antimicrobial efficacy against Staphylococcus aureus was limited to 16days. Consecutive temperature-triggers of our on-demand coating yielded little or no antimicrobial efficacy of silver-acetate release, but antimicrobially-effective chlorhexidine concentrations were observed over a time period of 60-80days. This attests to the clear advantage of on-demand coatings above ad libitum releasing coatings, that may have released their antimicrobial content before it is actually needed. Importantly, glass transition temperature of chlorhexidine loaded copolymers was lower (48°C) than of silver loaded ones (61°C), facilitating their clinical use. PMID:24950430

  6. Comparison of the Pharmacokinetics of Nicotine Following Single and Ad Libitum Use of a Tobacco Heating System or Combustible Cigarettes

    PubMed Central

    Picavet, Patrick; Haziza, Christelle; Lama, Nicola; Weitkunat, Rolf

    2016-01-01

    Introduction: We aimed to compare the pharmacokinetics of nicotine between the heat-not-burn Tobacco Heating System 2.1 (THS 2.1) and combustible cigarettes (CCs). We also examined whether the subjective urge to smoke was associated with the pharmacokinetics of nicotine. Methods: This open-label, randomized, two-period, two-sequence crossover study conducted in 28 healthy smokers assessed the pharmacokinetics of nicotine after single and ad libitum use of the THS 2.1 or CCs. During the 7-day confinement period, blood samples were drawn for pharmacokinetic analysis. Subjective effects related to THS 2.1 or CC use were assessed using the Questionnaire of Smoking Urges (QSU-Brief). Results: The nicotine delivery rate was similar with the THS 2.1 and CCs after single and ad libitum use. The time to the maximum nicotine concentration was 8 minutes after single use of the THS 2.1 and CCs. The time to the peak concentration following ad libitum use was similar between the THS 2.1 and CCs. The maximum plasma nicotine concentration after single use of the THS 2.1 was 8.4ng/mL, 70.3% of that obtained with CCs. A transient reduction from baseline in the urge to smoke of 40% was observed 15 minutes after the single use of both the THS 2.1 and CCs. The mean QSU-Brief total scores following single and ad libitum use were similar for the THS 2.1 and CCs. Conclusions: These results suggest that the THS 2.1 effectively delivers nicotine and achieves similar pharmacokinetic profiles to CCs. The THS 2.1 also reduced the urge to smoke similarly to CCs. Implications: Reducing exposure to toxicants and safer delivery of nicotine are among the strategies that may reduce the harm of smoking-related diseases. In the present study, we investigated the pharmacokinetics of nicotine and their effects on the urge to smoke using the THS 2.1. It was developed to replicate the ritual of smoking as closely as possible by providing nicotine in a way that mimics CC smoking, but limits pyrolysis and

  7. 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

  8. The Ratio of Macronutrients, Not Caloric Intake, Dictates Cardiometabolic Health, Aging, and Longevity in Ad Libitum-Fed Mice

    PubMed Central

    Solon-Biet, Samantha M.; McMahon, Aisling C.; Ballard, J. William O.; Ruohonen, Kari; Wu, Lindsay E.; Cogger, Victoria C.; Warren, Alessandra; Huang, Xin; Pichaud, Nicolas; Melvin, Richard G.; Gokarn, Rahul; Khalil, Mamdouh; Turner, Nigel; Cooney, Gregory J.; Sinclair, David A.; Raubenheimer, David; Le Couteur, David G.; Simpson, Stephen J.

    2016-01-01

    Summary The fundamental questions of what represents a macronutritionally balanced diet and how this maintains health and longevity remain unanswered. Here, the Geometric Framework, a state-space nutritional modeling method, was used to measure interactive effects of dietary energy, protein, fat, and carbohydrate on food intake, cardiometabolic phenotype, and longevity in mice fed one of 25 diets ad libitum. Food intake was regulated primarily by protein and carbohydrate content. Longevity and health were optimized when protein was replaced with carbohydrate to limit compensatory feeding for protein and suppress protein intake. These consequences are associated with hepatic mammalian target of rapamycin (mTOR) activation and mitochondrial function and, in turn, related to circulating branched-chain amino acids and glucose. Calorie restriction achieved by high-protein diets or dietary dilution had no beneficial effects on lifespan. The results suggest that longevity can be extended in ad libitum-fed animals by manipulating the ratio of macronutrients to inhibit mTOR activation. PMID:24606899

  9. Quantifying hepatic glycogen synthesis by direct and indirect pathways in rats under normal ad libitum feeding conditions.

    PubMed

    Soares, Ana F; Viega, Francisco J; Carvalho, Rui A; Jones, John G

    2009-01-01

    Hepatic glycogen synthesis from intact hexose (direct pathway) relative to that from gluconeogenic precursors (indirect pathway) was quantified in ad libitum-fed rats. Following (2)H(2)O administration and overnight feeding, the livers were removed and glycogen (2)H-enrichment was measured by (2)H NMR. Six controls and six rats rendered hyperglycemic by streptozotocin (STZ; fasting blood glucose = 385 +/- 31 mg/dl) were studied. The indirect pathway contribution, estimated as glycogen hydrogen 5 relative to hydrogen 2 enrichment, was 54% +/- 4% for control rats-similar to values from healthy, meal-fed humans. In STZ-treated rats, the indirect pathway contribution was significantly higher (68% +/- 4%, P < 0.05 vs. controls), similar to that of Type 1 diabetic (T1D) patients. In conclusion, sources of hepatic glycogen synthesis in rats during ad libitum nocturnal feeding were quantified by analysis of glycogen enrichment from (2)H(2)O. STZ caused alterations resembling the pathophysiology of hepatic glycogen synthesis in T1D patients.

  10. Effect of extended morning fasting upon ad libitum lunch intake and associated metabolic and hormonal responses in obese adults

    PubMed Central

    Chowdhury, E A; Richardson, J D; Tsintzas, K; Thompson, D; Betts, J A

    2016-01-01

    Background/Objectives: Breakfast omission is positively associated with obesity and increased risk of disease. However, little is known about the acute effects of extended morning fasting upon subsequent energy intake and associated metabolic/regulatory factors in obese adults. Subjects/Methods: In a randomised cross-over design, 24 obese men (n=8) and women (n=16) extended their overnight fast by omitting breakfast consumption or ingesting a typical carbohydrate-rich breakfast of 2183±393 kJ (521±94 kcal), before an ad libitum pasta lunch 3 h later. Blood samples were obtained throughout the day until 3 h post lunch and analysed for hormones implicated in appetite regulation, along with metabolic outcomes and subjective appetite measures. Results: Lunch intake was unaffected by extended morning fasting (difference=218 kJ, 95% confidence interval −54 kJ, 490 kJ; P=0.1) resulting in lower total intake in the fasting trial (difference=−1964 kJ, 95% confidence interval −1645 kJ, −2281 kJ; P<0.01). Systemic concentrations of peptide tyrosine–tyrosine and leptin were lower during the afternoon following morning fasting (P⩽0.06). Plasma-acylated ghrelin concentrations were also lower following the ad libitum lunch in the fasting trial (P<0.05) but this effect was not apparent for total ghrelin (P⩾0.1). Serum insulin concentrations were greater throughout the afternoon in the fasting trial (P=0.05), with plasma glucose also greater 1 h after lunch (P<0.01). Extended morning fasting did not result in greater appetite ratings after lunch, with some tendency for lower appetite 3 h post lunch (P=0.09). Conclusions: We demonstrate for the first time that, in obese adults, extended morning fasting does not cause compensatory intake during an ad libitum lunch nor does it increase appetite during the afternoon. Morning fasting reduced satiety hormone responses to a subsequent lunch meal but counterintuitively also reduced concentrations of

  11. Higher Daily Energy Expenditure and Respiratory Quotient, Rather Than Fat-Free Mass, Independently Determine Greater ad Libitum Overeating

    PubMed Central

    Thearle, Marie S.; Krakoff, Jonathan; Votruba, Susanne B.

    2015-01-01

    Context: Body fat-free mass (FFM), energy expenditure (EE), and respiratory quotient (RQ) are known predictors of daily food intake. Because FFM largely determines EE, it is unclear whether body composition per se or the underlying metabolism drives dietary intake. Objective: The objective of the study was to test whether 24-hour measures of EE and RQ and their components influence ad libitum food intake independently of FFM. Design and Participants: One hundred seven healthy individuals (62 males/45 females, 84 Native Americans/23 whites; age 33 ± 8 y; body mass index 33 ± 8 kg/m2; body fat 31% ± 8%) had 24-hour measures of EE in a whole-room indirect calorimeter during energy balance, followed by 3 days of ad libitum food intake using computerized vending machine systems. Body composition was estimated by dual-energy x-ray absorptiometry. Main Outcome Measures: FFM, 24-hour EE, RQ, spontaneous physical activity, sleeping EE (sleeping metabolic rate), awake and fed thermogenesis, and ad libitum food intake (INTAKE) were measured. Results: Higher 24-hour RQ (P < .001, partial R2 = 16%) and EE (P = .01, partial R2 = 7%), but not FFM (P = .65), were independent predictors of INTAKE. Mediation analysis demonstrated that 24-hour EE is responsible for 80% of the FFM effect on INTAKE (44.5 ± 16.9 kcal ingested per kilogram of FFM, P= .01), whereas the unique effect due to solely FFM was negligible (10.6 ± 23.2, P = .65). Spontaneous physical activity (r = 0.33, P = .001), but not sleeping metabolic rate (P = .71), positively predicted INTAKE, whereas higher awake and fed thermogenesis determined greater INTAKE only in subjects with a body mass index of 29 kg/m2 or less (r = 0.44, P = .01). Conclusions: EE and RQ, rather than FFM, independently determine INTAKE, suggesting that competitive energy-sensing mechanisms driven by the preferential macronutrient oxidation and total energy demands may regulate food intake. PMID:26086330

  12. Influence of a high-protein diet on energy balance in obese cats allowed ad libitum access to food.

    PubMed

    Wei, A; Fascetti, A J; Liu, K J; Villaverde, C; Green, A S; Manzanilla, E G; Havel, P J; Ramsey, J J

    2011-06-01

    The influence of a high-protein [HP, 47% of metabolizable energy (ME)] diet on energy balance was evaluated in obese cats allowed ad libitum access to food. Energy intake, body weight, body composition, energy expenditure, and concentrations of hormones and metabolites associated with carbohydrate and lipid metabolism (glucose, insulin, free fatty acids, triglycerides and leptin) were measured in cats after consuming either a moderate protein (MP, 27% of ME) or HP diet for 4 months. Indirect respiration calorimetry showed that resting and total energy expenditure (kJ/day) adjusted for either body weight or lean body mass was increased in cats consuming the HP in relation to MP diets. However, voluntary energy intake also was increased in the HP treatment and, thus, there was no difference in body weight between animals consuming the two diets. Body composition measurements using deuterium oxide dilution showed that dietary protein content did not alter amounts of either lean body mass or fat mass. No significant differences (p > 0.05) were observed between the two treatment groups for blood glucose, free fatty acid or leptin concentrations, although there was a trend (p = 0.054) towards an increase of serum insulin concentrations in the cats eating the HP diet. This study showed that short-term ad libitum feeding of an HP diet did not reduce food intake or promote weight loss in obese cats. However, energy expenditure was increased in the HP diet group and it is possible that this effect of HP might help promote weight loss when energy intake is restricted. PMID:21039925

  13. Snack food intake in ad libitum fed rats is triggered by the combination of fat and carbohydrates

    PubMed Central

    Hoch, Tobias; Pischetsrieder, Monika; Hess, Andreas

    2014-01-01

    Snack food like potato chips substantially contributes to energy intake in humans. In contrast to basic food, snacks are consumed additionally to other meals and may thereby lead to non-homeostatic energy intake. Snack food is also frequently associated with hedonic hyperphagia, a food intake independent from hunger. Analysis of brain activity patterns by manganese-enhanced MRI has previously revealed that the intake of potato chips in ad libitum fed rats strongly activates the reward system of the rat brain, which may lead to hedonic hyperphagia. The purpose of the present study was to develop a two-choice preference test to identify molecular determinants of snack food triggering extra food intake in ad libitum fed rats. Different kinds of test food were presented three times a day for 10 min each time. To minimize the influence of organoleptic properties, each test food was applied in a homogenous mixture with standard chow. Food intake as well as food intake-related locomotor activity were analyzed to evaluate the effects induced by the test foods in the two-choice preference test. In summary, fat (F), carbohydrates (CH), and a mixture of fat and carbohydrates (FCH) led to a higher food intake compared to standard chow. Notably, potato chip test food (PC) was highly significantly preferred over standard chow (STD) and also over their single main macronutrients F and CH. Only FCH induced an intake comparable to PC. Despite its low energy density, fat-free potato chip test food (ffPC) was also significantly preferred over STD and CH, but not over F, FCH, and PC. Thus, it can be concluded that the combination of fat and carbohydrates is a major molecular determinant of potato chips triggering hedonic hyperphagia. The applied two-choice preference test will facilitate future studies on stimulating and suppressive effects of other food components on non-homeostatic food intake. PMID:24744741

  14. Snack food intake in ad libitum fed rats is triggered by the combination of fat and carbohydrates.

    PubMed

    Hoch, Tobias; Pischetsrieder, Monika; Hess, Andreas

    2014-01-01

    Snack food like potato chips substantially contributes to energy intake in humans. In contrast to basic food, snacks are consumed additionally to other meals and may thereby lead to non-homeostatic energy intake. Snack food is also frequently associated with hedonic hyperphagia, a food intake independent from hunger. Analysis of brain activity patterns by manganese-enhanced MRI has previously revealed that the intake of potato chips in ad libitum fed rats strongly activates the reward system of the rat brain, which may lead to hedonic hyperphagia. The purpose of the present study was to develop a two-choice preference test to identify molecular determinants of snack food triggering extra food intake in ad libitum fed rats. Different kinds of test food were presented three times a day for 10 min each time. To minimize the influence of organoleptic properties, each test food was applied in a homogenous mixture with standard chow. Food intake as well as food intake-related locomotor activity were analyzed to evaluate the effects induced by the test foods in the two-choice preference test. In summary, fat (F), carbohydrates (CH), and a mixture of fat and carbohydrates (FCH) led to a higher food intake compared to standard chow. Notably, potato chip test food (PC) was highly significantly preferred over standard chow (STD) and also over their single main macronutrients F and CH. Only FCH induced an intake comparable to PC. Despite its low energy density, fat-free potato chip test food (ffPC) was also significantly preferred over STD and CH, but not over F, FCH, and PC. Thus, it can be concluded that the combination of fat and carbohydrates is a major molecular determinant of potato chips triggering hedonic hyperphagia. The applied two-choice preference test will facilitate future studies on stimulating and suppressive effects of other food components on non-homeostatic food intake.

  15. Snack food intake in ad libitum fed rats is triggered by the combination of fat and carbohydrates.

    PubMed

    Hoch, Tobias; Pischetsrieder, Monika; Hess, Andreas

    2014-01-01

    Snack food like potato chips substantially contributes to energy intake in humans. In contrast to basic food, snacks are consumed additionally to other meals and may thereby lead to non-homeostatic energy intake. Snack food is also frequently associated with hedonic hyperphagia, a food intake independent from hunger. Analysis of brain activity patterns by manganese-enhanced MRI has previously revealed that the intake of potato chips in ad libitum fed rats strongly activates the reward system of the rat brain, which may lead to hedonic hyperphagia. The purpose of the present study was to develop a two-choice preference test to identify molecular determinants of snack food triggering extra food intake in ad libitum fed rats. Different kinds of test food were presented three times a day for 10 min each time. To minimize the influence of organoleptic properties, each test food was applied in a homogenous mixture with standard chow. Food intake as well as food intake-related locomotor activity were analyzed to evaluate the effects induced by the test foods in the two-choice preference test. In summary, fat (F), carbohydrates (CH), and a mixture of fat and carbohydrates (FCH) led to a higher food intake compared to standard chow. Notably, potato chip test food (PC) was highly significantly preferred over standard chow (STD) and also over their single main macronutrients F and CH. Only FCH induced an intake comparable to PC. Despite its low energy density, fat-free potato chip test food (ffPC) was also significantly preferred over STD and CH, but not over F, FCH, and PC. Thus, it can be concluded that the combination of fat and carbohydrates is a major molecular determinant of potato chips triggering hedonic hyperphagia. The applied two-choice preference test will facilitate future studies on stimulating and suppressive effects of other food components on non-homeostatic food intake. PMID:24744741

  16. 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.

  17. Data on the phospholipid fatty acyl composition of retroperitoneal white adipose tissue in ad libitum fed and fasted mice

    PubMed Central

    Marks, Kristin A.; Marvyn, Phillip M.; Henao, Juan J. Aristizabal; Bradley, Ryan M.; Stark, Ken D.; Duncan, Robin E.

    2016-01-01

    Data are presented on the fatty acyl composition of phospholipid from retroperitoneal white adipose tissue of female mice that were either given ad libitum access to food or fasted for 16 h overnight prior to sacrifice. Our data show that total adipose phospholipid concentrations were more than 2-fold higher in the fasted animals compared with the fed animals (33.48±7.40 versus 16.57±4.43 μg phospholipid fatty acids/100 mg tissue). Concentrations of several individual phospholipid fatty acyl species, including palmitic acid (16:0), vaccenic acid (18:1n-7), linoleic acid (18:2n-6), dihomo-gamma-linolenic acid (20:3n-6), arachidonic acid (20:4n-6), eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3), as well as total phospholipid saturated fatty acids, n-6 polyunsaturated fatty acids and n-3 polyunsaturated fatty acids, were significantly higher in adipose tissue from the fasted animals compared with the fed animals. However, when the relative abundance of phospholipid fatty acyl species was analyzed, only 20:4n-6 was specifically enriched (by ~2.5-fold) in adipose phospholipid with fasting. PMID:27014729

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

    PubMed

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

    1998-03-01

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

  19. Sensory-specific satiety for a food is unaffected by the ad libitum intake of other foods during a meal. Is SSS subject to dishabituation?

    PubMed

    Meillon, S; Thomas, A; Havermans, R; Pénicaud, L; Brondel, L

    2013-04-01

    Sensory-specific satiety (SSS) is defined as a decrease in the pleasantness of a specific food that has just been eaten to satiation, while other non-eaten foods remain pleasant. The objectives of this study were the following: (1) to investigate whether SSS for a food is affected by the ad libitum intake of other foods presented sequentially during a meal, (2) to compare the development of SSS when foods are presented simultaneously or sequentially during a meal, and (3) to examine whether SSS is modified when foods are presented in an unusual order within a meal. Twelve participants participated in three tasting sessions. In session A, SSS for protein-, fat- and carbohydrate-rich sandwiches was measured after the ad libitum consumption of single type of each of these foods. In session B, SSS was measured for the same three foods consumed ad libitum but presented simultaneously. Session C was identical to session A, except that the presentation order of the three foods was reversed. The results indicate that once SSS for a given food is reached, the ad libitum consumption of other foods with different sensory characteristics does not decrease SSS, regardless of the order in which the foods are presented. Once reached, SSS is thus not subject to dishabituation during a meal.

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

    PubMed

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

    1998-03-01

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

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

    PubMed

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

    2012-12-01

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

  2. Reappraise the Situation but Express Your Emotions: Impact of Emotion Regulation Strategies on ad libitum Food Intake.

    PubMed

    Taut, Diana; Renner, Britta; Baban, Adriana

    2012-01-01

    Research investigating the role of maladaptive emotion regulation (ER) on food intake has exclusively focused on food intake in a forced consumption situation. In contrast, the present study examined the effect of negative emotions (fear, negative affect) and ER strategies (suppression, reappraisal) on food intake in a non-forced, free eating setting where participants (N = 165) could choose whether and how much they ate. This free (ad libitum) eating approach enabled, for the first time, the testing of (1) whether eating (yes/no) is used as a secondary ER strategy and (2) whether the amount of food intake differed, depending on the ER strategy. In order to produce a more ecologically valid design, ER strategy manipulation was realized while exposing participants to emotion induction procedures. To induce an initial negative emotional state, a movie clip was presented without ER instruction. The instructions to regulate emotions (suppression, reappraisal, no ER instruction) then preceded a second clip. The results show that whereas about two-thirds of the control (no ER instruction) and suppression groups began to eat, only one-third of the reappraisal group did. However, when reappraisers began to eat, they ate as much as participants in the suppression and control groups. Accordingly, the results suggest that when people are confronted with a negative event, eating is used as a secondary coping strategy when the enacted ER is ineffective. Conversely, an adaptive ER such as reappraisal decreases the likelihood of eating in the first place, even when ER is employed during rather than before the unfolding of the negative event. Consequently, the way we deal with negative emotions might be more relevant for explaining emotional eating than the distress itself.

  3. Ad libitum fluid intake leads to no leg swelling in male Ironman triathletes – an observational field study

    PubMed Central

    2012-01-01

    Background An association between fluid intake and limb swelling has been described for 100-km ultra-marathoners. We investigated a potential development of peripheral oedemata in Ironman triathletes competing over 3.8 km swimming, 180 km cycling and 42.2 km running. Methods In 15 male Ironman triathletes, fluid intake, changes in body mass, fat mass, skeletal muscle mass, limb volumes and skinfold thickness were measured. Changes in renal function, parameters of skeletal muscle damage, hematologic parameters and osmolality in both serum and urine were determined. Skinfold thicknesses at hands and feet were measured using LIPOMETER® and changes of limb volumes were measured using plethysmography. Results The athletes consumed a total of 8.6 ± 4.4 L of fluids, equal to 0.79 ± 0.43 L/h. Body mass, skeletal muscle mass and the volume of the lower leg decreased (p <0.05), fat mass, skinfold thicknesses and the volume of the arm remained unchanged (p >0.05). The decrease in skeletal muscle mass was associated with the decrease in body mass (p <0.05). The decrease in the lower leg volume was unrelated to fluid intake (p >0.05). Haemoglobin, haematocrit and serum sodium remained unchanged (p >0.05). Osmolality in serum and urine increased (p <0.05). The change in body mass was related to post-race serum sodium concentration ([Na+]) (r = −0.52, p <0.05) and post-race serum osmolality (r = −0.60, p <0.05). Conclusions In these Ironman triathletes, ad libitum fluid intake maintained plasma [Na+] and plasma osmolality and led to no peripheral oedemata. The volume of the lower leg decreased and the decrease was unrelated to fluid intake. Future studies may investigate ultra-triathletes competing in a Triple Iron triathlon over 11.4 km swimming, 540 km cycling and 126.6 km running to find an association between fluid intake and the development of peripheral oedemata. PMID:22937792

  4. Circadian variation in heart rate, blood pressure, body temperature and EEG of immature broiler breeder chickens in restricted-fed and ad libitum-fed states.

    PubMed

    Savory, C J; Kostal, L; Nevison, I M

    2006-10-01

    1. Heart rate, intra-aortic blood pressure, deep body temperature and telencephalic EEG were monitored by radiotelemetry in 6 freely moving immature broiler breeders (three in each of two years), during routine food restriction and then ad libitum feeding, over two 24-h periods in each feeding state.2. Heart rate, blood pressure and body temperature were all higher during ad libitum than restricted feeding, and heart rate and body temperature were higher by day (12 h) than at night (12 h). The decreases in heart rate and body temperature at night were greater during restricted than ad libitum feeding. Blood pressure tended to be higher at night, except in year 2 during restricted feeding. Body temperature and ambient temperature were higher in year 2 than year 1.3. During restricted feeding, marked peaks in heart rate, blood pressure and body temperature in the 15 min after provision of the daily food ration at 09:00 h, when birds were eating, were equivalent to corresponding values seen during ad libitum feeding.4. Relative powers in delta (1 to 4 Hz) and theta (4 to 8 Hz) frequency bands of the EEG power spectrum were higher at night in year 2 only, while power in the alpha (8 to 12 Hz) band was higher at night in both years.5. It is concluded that most of the variation in heart rate, blood pressure and body temperature between feeding states and times of day/night can be accounted for in terms of variation in food intake and energy expenditure. The greater slow wave (delta, theta) EEG activity seen after lights-off in year 2 may reflect non-paradoxical sleep at that time.

  5. Wholegrain vs. refined wheat bread and pasta. Effect on postprandial glycemia, appetite, and subsequent ad libitum energy intake in young healthy adults.

    PubMed

    Kristensen, Mette; Jensen, Morten G; Riboldi, Giancarlo; Petronio, Michela; Bügel, Susanne; Toubro, Søren; Tetens, Inge; Astrup, Arne

    2010-02-01

    Wholegrain foods have received much attention in recent years, and have been proposed to play a role in energy regulation through lowering of postprandial glycemia and appetite. This randomized crossover single meal study in 16 young adults was conducted to test the effect of iso-caloric meals based on wholemeal wheat breads and pasta in comparison to similar refined wheat products on postprandial glycemia, appetite and ad libitum energy intake (EI). Test meals (50 g carbohydrates; 2MJ) consisted of refined wheat bread (RWB), wholegrain wheat bread (WWB), refined wheat pasta (RWP) and wholegrain wheat pasta (WWP) and were served after an overnight fast. Appetite ratings and blood glucose were assessed for 180 min after which an ad libitum lunch meal was served and EI measured. The 180 min glucose responses were similar for wholemeal and refined products, but pasta meals gave significantly lower glucose responses. Only RWP had a lower glycemic index compared to RWB. WWB, but not WWP, resulted in increased satiety and reduced hunger compared to RWB. Ad libitum EI did not differ. In conclusion, the results show that wholemeal breads increased satiety measures compared to their refined counterparts; however no significant effect on subsequent EI was observed.

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

    PubMed

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

    2015-06-01

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

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

    PubMed

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

    2015-06-01

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

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

    PubMed

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

    2015-03-01

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

  9. Ad libitum food intake on a "cafeteria diet" in Native American women: relations with body composition and 24-h energy expenditure.

    PubMed

    Larson, D E; Tataranni, P A; Ferraro, R T; Ravussin, E

    1995-11-01

    Epidemiologic studies consistently report associations between obesity and dietary fat but not total energy intake. We measured ad libitum food intake in a laboratory setting and evaluated its relation to body weight and composition, energy expenditure, and macronutrient utilization in 28 women of Pima-Papago heritage (aged 27 +/- 7 y, 85.3 +/- 19.0 kg, 44 +/- 6% body fat; means +/- SD). All women were studied during the follicular phase of the menstrual cycle. After a 4-d weight-maintenance period, the volunteers selected their food for 5 d from computerized vending machines offering a variety of familiar and preferred foods, ie, a "cafeteria diet". Twenty-four-hour energy expenditure and substrate oxidation were measured in a respiratory chamber on the 4th d o weight maintenance and the 5th d of ad libitum intake. Average ad libitum intake was 13,732 +/- 4238 kJ/d (11 +/- 1% protein, 40 +/- 1% fat, 49 +/- 4% carbohydrate), ie, moderate overeating by 27 +/- 37% above weight maintenance requirements (range: -27% to 124%). Percent body fat correlated with daily energy intake (r = 0.53, P < 0.01), the degree of overeating (r = 0.41, P < 0.05), and the selection of a diet higher in fat and lower in carbohydrate (r = 0.70 and r = -0.63, respectively, P < 0.001). Excess carbohydrate intake caused an increase in carbohydrate oxidation (r = 0.51, P < 0.01), whereas excess fat intake resulted in a decrease in fat oxidation (r = -0.53, P < 0.01) and thus a positive fat balance of 85 +/- 65 g/d. The positive relations among degrees of obesity, dietary fat intake and overeating, and the fact that dietary fat does not induce fat oxidation, support the hypothesis that dietary fat promotes obesity in women. PMID:7572735

  10. Carbohydrate-rich breakfast attenuates glycaemic, insulinaemic and ghrelin response to ad libitum lunch relative to morning fasting in lean adults.

    PubMed

    Chowdhury, Enhad A; Richardson, Judith D; Tsintzas, Kostas; Thompson, Dylan; Betts, James A

    2015-07-14

    Breakfast omission is associated with obesity and CVD/diabetes, but the acute effects of extended morning fasting upon subsequent energy intake and metabolic/hormonal responses have received less attention. In a randomised cross-over design, thirty-five lean men (n 14) and women (n 21) extended their overnight fast or ingested a typical carbohydrate-rich breakfast in quantities relative to RMR (i.e. 1963 (sd 238) kJ), before an ad libitum lunch 3 h later. Blood samples were obtained hourly throughout the day until 3 h post-lunch, with subjective appetite measures assessed. Lunch intake was greater following extended fasting (640 (sd 1042) kJ, P< 0.01) but incompletely compensated for the omitted breakfast, with total intake lower than the breakfast trial (3887 (sd 1326) v. 5213 (sd 1590) kJ, P< 0.001). Systemic concentrations of peptide tyrosine-tyrosine and leptin were greater during the afternoon following breakfast (both P< 0.05) but neither acylated/total ghrelin concentrations were suppressed by the ad libitum lunch in the breakfast trial, remaining greater than the morning fasting trial throughout the afternoon (all P< 0.05). Insulin concentrations were greater during the afternoon in the morning fasting trial (all P< 0.01). There were no differences between trials in subjective appetite during the afternoon. In conclusion, morning fasting caused incomplete energy compensation at an ad libitum lunch. Breakfast increased some anorectic hormones during the afternoon but paradoxically abolished ghrelin suppression by the second meal. Extending morning fasting until lunch altered subsequent metabolic and hormonal responses but without greater appetite during the afternoon. The present study clarifies the impact of acute breakfast omission and adds novel insights into second-meal metabolism. PMID:26004166

  11. Carbohydrate-rich breakfast attenuates glycaemic, insulinaemic and ghrelin response to ad libitum lunch relative to morning fasting in lean adults.

    PubMed

    Chowdhury, Enhad A; Richardson, Judith D; Tsintzas, Kostas; Thompson, Dylan; Betts, James A

    2015-07-14

    Breakfast omission is associated with obesity and CVD/diabetes, but the acute effects of extended morning fasting upon subsequent energy intake and metabolic/hormonal responses have received less attention. In a randomised cross-over design, thirty-five lean men (n 14) and women (n 21) extended their overnight fast or ingested a typical carbohydrate-rich breakfast in quantities relative to RMR (i.e. 1963 (sd 238) kJ), before an ad libitum lunch 3 h later. Blood samples were obtained hourly throughout the day until 3 h post-lunch, with subjective appetite measures assessed. Lunch intake was greater following extended fasting (640 (sd 1042) kJ, P< 0.01) but incompletely compensated for the omitted breakfast, with total intake lower than the breakfast trial (3887 (sd 1326) v. 5213 (sd 1590) kJ, P< 0.001). Systemic concentrations of peptide tyrosine-tyrosine and leptin were greater during the afternoon following breakfast (both P< 0.05) but neither acylated/total ghrelin concentrations were suppressed by the ad libitum lunch in the breakfast trial, remaining greater than the morning fasting trial throughout the afternoon (all P< 0.05). Insulin concentrations were greater during the afternoon in the morning fasting trial (all P< 0.01). There were no differences between trials in subjective appetite during the afternoon. In conclusion, morning fasting caused incomplete energy compensation at an ad libitum lunch. Breakfast increased some anorectic hormones during the afternoon but paradoxically abolished ghrelin suppression by the second meal. Extending morning fasting until lunch altered subsequent metabolic and hormonal responses but without greater appetite during the afternoon. The present study clarifies the impact of acute breakfast omission and adds novel insights into second-meal metabolism.

  12. Acute effects of protein composition and fibre enrichment of yogurt consumed as snacks on appetite sensations and subsequent ad libitum energy intake in healthy men.

    PubMed

    Doyon, Caroline Y; Tremblay, Angelo; Rioux, Laurie-Eve; Rhéaume, Caroline; Cianflone, Katherine; Poursharifi, Pegah; Turgeon, Sylvie L

    2015-10-01

    The objective of the study was to assess the impact of protein composition and/or fibre enrichment of yogurt on appetite sensations and subsequent energy intake. In this double-blind crossover study, 20 healthy men (aged 32.4 ± 9.1 years) were submitted to 5 randomized testing sessions, during which they had to consume 5 isocaloric and isonproteinemic yogurt snacks (120-g servings, ∼230 kJ, ∼4.5 g protein) differing by their casein-to-whey protein ratio (C:W) or dietary fibre content: (i) control C:W = 2.8:1; (ii) high whey (HW) C:W = 1.5:1, and fibre-enriched formulations using control; (iii) 2.4 g of inulin; (iv) 1.9 g of inulin and 0.5 g of β-glucan (+IN-βG); and (v) 0.5 g of β-glucan. Appetite sensations were assessed using 150-mm visual analog scales. Plasma variables (glucose, insulin, ghrelin) were measured at 30-min intervals post-yogurt consumption for 2 h. Finally, energy intakes during ad libitum lunches offered 2 h after yogurt snacks were recorded. None of the yogurts impacted appetite sensations. Ad libitum energy intake was significantly different only between HW and control yogurts (-812 kJ; p = 0.03). Regarding post-yogurt plasma variables, a significant difference was found only between ghrelin area under the curve of the +IN-βG and the HW yogurts (-15 510 pmol/L per 120 min, p = 0.04). In conclusion, although appetite sensations were not influenced by variations in yogurts' protein compositions, a reduced energy intake was observed during the ad libitum lunch after the HW yogurt that may be attributable to its lower C:W. Surprisingly, the fibre enrichments studied did not exert effect on appetite sensations and energy intake.

  13. Acute effects of protein composition and fibre enrichment of yogurt consumed as snacks on appetite sensations and subsequent ad libitum energy intake in healthy men.

    PubMed

    Doyon, Caroline Y; Tremblay, Angelo; Rioux, Laurie-Eve; Rhéaume, Caroline; Cianflone, Katherine; Poursharifi, Pegah; Turgeon, Sylvie L

    2015-10-01

    The objective of the study was to assess the impact of protein composition and/or fibre enrichment of yogurt on appetite sensations and subsequent energy intake. In this double-blind crossover study, 20 healthy men (aged 32.4 ± 9.1 years) were submitted to 5 randomized testing sessions, during which they had to consume 5 isocaloric and isonproteinemic yogurt snacks (120-g servings, ∼230 kJ, ∼4.5 g protein) differing by their casein-to-whey protein ratio (C:W) or dietary fibre content: (i) control C:W = 2.8:1; (ii) high whey (HW) C:W = 1.5:1, and fibre-enriched formulations using control; (iii) 2.4 g of inulin; (iv) 1.9 g of inulin and 0.5 g of β-glucan (+IN-βG); and (v) 0.5 g of β-glucan. Appetite sensations were assessed using 150-mm visual analog scales. Plasma variables (glucose, insulin, ghrelin) were measured at 30-min intervals post-yogurt consumption for 2 h. Finally, energy intakes during ad libitum lunches offered 2 h after yogurt snacks were recorded. None of the yogurts impacted appetite sensations. Ad libitum energy intake was significantly different only between HW and control yogurts (-812 kJ; p = 0.03). Regarding post-yogurt plasma variables, a significant difference was found only between ghrelin area under the curve of the +IN-βG and the HW yogurts (-15 510 pmol/L per 120 min, p = 0.04). In conclusion, although appetite sensations were not influenced by variations in yogurts' protein compositions, a reduced energy intake was observed during the ad libitum lunch after the HW yogurt that may be attributable to its lower C:W. Surprisingly, the fibre enrichments studied did not exert effect on appetite sensations and energy intake. PMID:26394259

  14. Validating growth and development of a seabird as an indicator of food availability: captive-reared Caspian Tern chicks fed ad libitum and restricted diets

    USGS Publications Warehouse

    Lyons, Donald E.; Roby, Daniel D.

    2011-01-01

    For seabirds raising young under conditions of limited food availability, reducing chick provisioning and chick growth rates are the primary means available to avoid abandonment of a breeding effort. For most seabirds, however, baseline data characterizing chick growth and development under known feeding conditions are unavailable, so it is difficult to evaluate chick nutritional status as it relates to foraging conditions near breeding colonies. To address this need, we examined the growth and development of young Caspian Terns (Hydroprogne caspia), a cosmopolitan, generalist piscivore, reared in captivity and fed ad libitum and restricted (ca. one-third lower caloric intake) diets. Ad libitum-fed chicks grew at similar rates and achieved a similar size at fledging as previously documented for chicks in the wild and had energetic demands that closely matched allometric predictions. We identified three general characteristics of food-restricted Caspian Tern chicks compared to ad libitum chicks: (1) lower age-specific body mass, (2) lower age-specific skeletal and feather size, such as wing chord length, and (3) heightened levels of corticosterone in blood, both for baseline levels and in response to acute stress. Effects of diet restriction on feather growth (10-11% slower growth in diet-restricted chicks) were less pronounced than effects on structural growth (37-52% slower growth) and body mass (24% lower at fledging age), apparently due to preferential allocation of food resources to maintain plumage growth. Our results suggest that measurements of chick body mass and feather development (e.g., wing chord or primary length) or measurement of corticosterone levels in the blood would allow useful evaluation of the nutritional status of chicks reared in the wild and of food availability in the foraging range of adults. Such evaluations could also inform demography studies (e.g., predict future recruitment) and assist in evaluating designated piscivorous waterbird

  15. Impact of fluid restriction and ad libitum water intake or an 8% carbohydrate-electrolyte beverage on skill performance of elite adolescent basketball players.

    PubMed

    Carvalho, Pedro; Oliveira, Bruno; Barros, Renata; Padrão, Patricia; Moreira, Pedro; Teixeira, Vitor Hugo

    2011-06-01

    Twelve adolescent athletes underwent, in a crossover-design study, 3 separate 90-min training sessions in the following conditions: no fluid ingestion allowed (NF), ad libitum ingestion of water (W), and ad libitum ingestion of a commercial 8% carbohydrate-electrolyte sports beverage (CSB). After each session athletes performed a set of basketball drills (2-point, 3-point, and free-throw shootout, suicide sprints, and defensive zigzags). Body weight (before and after sessions), rating of perceived exertion (RPE), urine color, and beverage acceptability were determined in each session. Athletes also completed a survey about their knowledge and behaviors regarding hydration and fluid replacement. The percentage of weight loss was significantly higher in NF (2.46% ± 0.87%) than in the other 2 conditions (W, 1.08% ± 0.67%, p = .006; CSB, 0.65% ± 0.62%, p = .001) but also higher in W than CSB (p = .012). RPE was higher in NF (16.8 ± 1.96) than in the W (14.2 ± 1.99, p = .004) and CSB (13.3 ± 2.06, p = .002) trials. Athletes' fluid intake was positively correlated with proper self-reported behaviors (r = .75, p = .005) and knowledge (r = .76, p = .004) about fluid and hydration. In conclusion, fluid restriction during exercise was associated with a greater level of dehydration and increased perceived exertion but had no impact on basketball performance compared with ad libitum drinking of water or a CSB. Athletes with more knowledge about hydration and better self-reported hydration behaviors ingested more fluids during training sessions.

  16. Exercise Does Not Protect against Peripheral and Central Effects of a High Cholesterol Diet Given Ad libitum in Old ApoE−/− Mice

    PubMed Central

    Di Cataldo, Vanessa; Géloën, Alain; Langlois, Jean-Baptiste; Chauveau, Fabien; Thézé, Benoît; Hubert, Violaine; Wiart, Marlène; Chirico, Erica N.; Rieusset, Jennifer; Vidal, Hubert; Pialoux, Vincent; Canet-Soulas, Emmanuelle

    2016-01-01

    Aim: Advanced atherosclerosis increases inflammation and stroke risk in the cerebral vasculature. Exercise is known to improve cardio-metabolic profiles when associated with a caloric restriction, but it remains debated whether it is still beneficial without the dietary control. The aim of this study was to determine both the peripheral and central effects of exercise training combined with a cholesterol-rich diet given ad libitum in old ApoE−/− mice. Methods: Forty-five-weeks old obese ApoE−/− mice fed with a high cholesterol diet ad libitum were divided into Exercise-trained (EX; running wheel free access) and Sedentary (SED) groups. Insulin tolerance and brain imaging were performed before and after the twelve-weeks training. Tissue insulin resistance, oxidative stress, and inflammation markers in plasma, aorta, and brain were then assessed. Results: In EX ApoE−/− mice, no beneficial effect of exercise was observed on weight, abdominal fat, metabolic parameters, oxidative stress, or inflammation compared to SED. Despite the regular exercise training in ApoE−/− EX mice (mean of 12.5 km/week during 12 weeks), brain inflammation imaging score was significantly associated with increased blood brain barrier (BBB) leakage evaluated by imaging follow-up (r2 = 0.87; p = 0.049) with a faster evolution compared to SED ApoE−/−mice. Conclusion: We conclude that in a context of high cardio-metabolic risk, exercise does not provide any protective effect in old ApoE−/− animals under high cholesterol diet given ad libitum. Peripheral (insulin sensitivity and oxidative/inflammatory status) but also central features (BBB preservation and protection against inflammation) did not show any benefits of exercise. Indeed, there was a fast induction of irreversible brain damage that was more pronounced in exercise-trained ApoE−/− mice. PMID:27766082

  17. Maintained total body water content and serum sodium concentrations despite body mass loss in female ultra-runners drinking ad libitum during a 100 km race.

    PubMed

    Knechtle, Beat; Senn, Oliver; Imoberdorf, Reinhard; Joleska, Irena; Wirth, Andrea; Knechtle, Patrizia; Rosemann, Thomas

    2010-01-01

    We investigated in 11 female ultra-runners during a 100 km ultra-run, the association between fluid intake and prevalence of exercise-associated hyponatremia in a cross-sectional study. Athletes drank ad libitum and recorded their fluid intake. They competed at 8.0 (1.0) km/h and finished within 762 (91) min. Fluid intake was 4.1 (1.3) L during the race, equal to 0.3 (0.1) L/h. Body mass decreased by 1.5 kg (p< 0.01); pre race body mass was related to speed in the race (r = -0.78, p< 0.05); and change (Delta) in body mass was not associated with speed in the race. Change in body mass was positively (r = 0.70; p< 0.05), and Delta urinary specific gravity negatively (r = -0.67; p< 0.05), correlated to Delta percent total body water. Changes in body mass were not related to fluid intake during the race. Fluid intake was not correlated to running speed and showed no association with either Delta percent total body water nor Delta [Na] in plasma. Fluid intake showed no relationship with both Delta haematocrit and Delta plasma volume. No exercise-associated hyponatremia occurred. Female ultra- runners consuming fluids ad libitum during the race experienced no fluid overload, and ad libitum drinking protects against exercise-associated hyponatremia. The reported higher incidence of exercise-associated hyponatremia in women is not really a gender effect but due to women being more prone to overdrink. PMID:20199991

  18. Repeated consumption of a large volume of liquid and semi-solid foods increases ad libitum intake, but does not change expected satiety.

    PubMed

    Hogenkamp, P S; Mars, M; Stafleu, A; de Graaf, C

    2012-10-01

    Food intake and a food's expected satiating effect initially rely on sensory attributes. People will learn about the food's satiating capacity by exposure. We investigated whether repeated consumption changed the expected satiety effects and intake of iso-energetic liquid and semi-solid foods. In a randomised cross-over study, participants (n=53; age: 21±2.9 y; BMI: 21.8±2.0 kg/m²) consumed one of two iso-energetic dairy foods (liquid or semi-solid) for breakfast in each 5-day test condition. Expectations regarding satiety were measured on days 1, 2, and 5. Foods were offered ad libitum on days 1 and 5 and in a fixed volume on days 2-4. Appetite sensations were rated up to 180 min after the start of the session on fixed time points. Expected satiety effects of the semi-solid food were higher than of the liquid food on all days (p<0.0001). Ad libitum intake of the liquid food was higher than of the semi-solid food on day 1 (liquid: 391±177 g, semi-solid: 277±98 g; p<0.0001) and day 5 (liquid: 477±161 g, semi-solid: 375±148 g; p<0.0001). On day 2, hunger was rated lower and fullness rated higher after the semi-solid compared with the liquid food; on day 4, no differences were observed (significant product∗ exposure interaction AUC). Changes in hunger and fullness indicated that the fixed volumes of liquid and solid food were perceived to be equally satiating after repeated consumption, but this did not result in the anticipated changes: expected satiety effects remained lower, and ad libitum intake higher for the liquid compared with the semi-solid food. The effect of texture on a food's expected satiety effects and its ad libitum intake appears to be large, also after repeated consumption. Expectations based on sensory cues are not easily changed.

  19. Acute effects of active gaming on ad libitum energy intake and appetite sensations of 8-11-year-old boys.

    PubMed

    Allsop, Susan; Dodd-Reynolds, Caroline J; Green, Benjamin P; Debuse, Dorothée; Rumbold, Penny L S

    2015-12-28

    The present study examined the acute effects of active gaming on energy intake (EI) and appetite responses in 8-11-year-old boys in a school-based setting. Using a randomised cross-over design, twenty-one boys completed four individual 90-min gaming bouts, each separated by 1 week. The gaming bouts were (1) seated gaming, no food or drink; (2) active gaming, no food or drink; (3) seated gaming with food and drink offered ad libitum; and (4) active gaming with food and drink offered ad libitum. In the two gaming bouts during which foods and drinks were offered, EI was measured. Appetite sensations - hunger, prospective food consumption and fullness - were recorded using visual analogue scales during all gaming bouts at 30-min intervals and at two 15-min intervals post gaming. In the two bouts with food and drink, no significant differences were found in acute EI (MJ) (P=0·238). Significant differences were detected in appetite sensations for hunger, prospective food consumption and fullness between the four gaming bouts at various time points. The relative EI calculated for the two gaming bouts with food and drink (active gaming 1·42 (sem 0·28) MJ; seated gaming 2·12 (sem 0·25) MJ) was not statistically different. Acute EI in response to active gaming was no different from seated gaming, and appetite sensations were influenced by whether food was made available during the 90-min gaming bouts. PMID:26435259

  20. Acute effects of active gaming on ad libitum energy intake and appetite sensations of 8-11-year-old boys.

    PubMed

    Allsop, Susan; Dodd-Reynolds, Caroline J; Green, Benjamin P; Debuse, Dorothée; Rumbold, Penny L S

    2015-12-28

    The present study examined the acute effects of active gaming on energy intake (EI) and appetite responses in 8-11-year-old boys in a school-based setting. Using a randomised cross-over design, twenty-one boys completed four individual 90-min gaming bouts, each separated by 1 week. The gaming bouts were (1) seated gaming, no food or drink; (2) active gaming, no food or drink; (3) seated gaming with food and drink offered ad libitum; and (4) active gaming with food and drink offered ad libitum. In the two gaming bouts during which foods and drinks were offered, EI was measured. Appetite sensations - hunger, prospective food consumption and fullness - were recorded using visual analogue scales during all gaming bouts at 30-min intervals and at two 15-min intervals post gaming. In the two bouts with food and drink, no significant differences were found in acute EI (MJ) (P=0·238). Significant differences were detected in appetite sensations for hunger, prospective food consumption and fullness between the four gaming bouts at various time points. The relative EI calculated for the two gaming bouts with food and drink (active gaming 1·42 (sem 0·28) MJ; seated gaming 2·12 (sem 0·25) MJ) was not statistically different. Acute EI in response to active gaming was no different from seated gaming, and appetite sensations were influenced by whether food was made available during the 90-min gaming bouts.

  1. Total Body Water, Electrolyte, and Thermoregulatory Responses to Ad Libitum Water Replacement Using Two Different Water Delivery Systems During a 19-km Route March.

    PubMed

    Nolte, Heinrich W; Nolte, Kim; van der Meulen, Julia

    2015-11-01

    Hands-free hydration systems are often advocated for improved hydration and performance in military populations. The aim was to assess whether such systems indeed result in improved hydration in exercising soldiers. Subjects were required to complete a route march while consuming water ad libitum from either a hydration bladder (BG) or traditional canteen (CG). Water intakes of 538 ml·h⁻¹ (BG) and 533 ml·h⁻¹ (CG) resulted in no differences for changes in body mass, serum [Na], plasma osmolality, total body water, or time required to complete the march. There were no differences between peak exercise core temperature of the BG (38.9° C) and CG (38.7° C) groups. There were no differences between the groups for fluid balance, thermoregulation, or performance. This is a not a surprising finding because the amount of fluid consumed ad libitum is determined by changes in serum osmolality and not the fluid delivery system as often proposed. PMID:26506205

  2. Voluntary feed intake and leptin sensitivity in ad libitum fed obese ponies following a period of restricted feeding: a pilot study.

    PubMed

    Van Weyenberg, S; Buyse, J; Kalmar, I D; Swennen, Q; Janssens, G P J

    2013-08-01

    The relation between plasma leptin and daily ad libitum roughage intake was evaluated during a 14-day period in eight obese Shetland ponies. When the feeding strategy was changed from maintenance feeding to ad libitum feeding, feed intake increased the first day, decreased the second day and increased again during the following days to reach a constant level after 8 days. Plasma leptin concentration increased during the first 2 days, but remained constant afterwards. Although the same pattern was found in all ponies, the magnitude of the increase in leptin on day 1 and the resulting decrease in feed intake on day 2 differed between ponies. A lower anorectic effect was seen in ponies with higher initial leptin concentration, suggesting the presence of different degrees in leptin sensitivity in obese ponies. High leptin production in a attempt to compensate for the decrease in leptin sensitivity might explain large variations in plasma leptin among obese ponies with similar body condition score. Further research is necessary to clarify whether the reduced leptin sensitivity precedes obesity in equines or vice versa.

  3. 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

  4. Effekt einer ad libitum verzehrten fettreduzierten Kost, reich an Obst, Gemüse und Milchprodukten auf den Blutdruck bei Borderline-Hypertonikern

    NASA Astrophysics Data System (ADS)

    Möseneder, Jutta M.

    2002-01-01

    In der randomisierten, multizentrischen DASH-Studie (Dietary Approaches to Stop Hy-pertension), die unter kontrollierten Bedingungen stattfand, führte eine fettreduzierte Mischkost, reich an Obst, Gemüse und Milchprodukten, bei Borderline-Hypertonikern zu einer signifikanten Blutdrucksenkung. Während der Studienphase wurden Körpermasse, Natrium-Aufnahme sowie Alkoholzufuhr aufgrund der bekannten Einflussnahme auf den Blutdruck konstant gehalten. In der eigenen Pilot-Studie sollte untersucht werden, ob das Ergebnis der DASH-Studie (i) mit deutschen Hypertonikern und (ii) unter habituellen Ernährungs- und Lebensbedingungen mit regelmäßig durchgeführter Ernährungsberatung und ad libitum Verzehr anstelle des streng kontrollierten Studienansatzes bestätigt werden kann. Eine Konstanz der Körpermasse, der Natrium-Urinausscheidung (unter diesem Studienansatz valider als die Aufnahme) und des Alkoholkonsums wurde vorausgesetzt. Die Studienpopulation setzte sich aus 53 übergewichtigen Probanden mit einer nicht medikamentös therapierten Borderline-Hypertonie und ohne Stoffwechselerkrankungen zusammen. Die Studienteilnehmer wurden randomisiert entweder der Idealgruppe mit einer fettarmen Kost reich an Milchprodukten, Obst und Gemüse (ähnlich der DASH-Idealgruppe) oder der Kontrollgruppe mit habitueller Ernährungsweise zugeteilt. Über einen Zeitraum von fünf Wochen wurde den Probanden etwa 50% ihres täglichen Lebensmittelbedarfes entsprechend ihrer Gruppenzugehörigkeit kostenfrei zur Verfügung gestellt. Gelegenheitsblutdruckmessungen und 24h-Blutdruckmessungen, Ernährungs- und Aktivitätsprotokolle, Blut- und Urinproben sowie anthropometrische Messungen wurden vor, während und fünf Wochen nach der Interventionsphase durchgeführt. Die Ergebnisse zeigen, dass in der Idealgruppe keine signifikante Blutdrucksenkung beobachtet werden konnte. Dies lässt sich durch die Tatsache erklären, dass die Lebens-mittel- und Nährstoffaufnahme der deutschen

  5. Effekt einer ad libitum verzehrten fettreduzierten Kost, reich an Obst, Gemüse und Milchprodukten auf den Blutdruck bei Borderline-Hypertonikern

    NASA Astrophysics Data System (ADS)

    Möseneder, Jutta M.

    2002-01-01

    In der randomisierten, multizentrischen DASH-Studie (Dietary Approaches to Stop Hy-pertension), die unter kontrollierten Bedingungen stattfand, führte eine fettreduzierte Mischkost, reich an Obst, Gemüse und Milchprodukten, bei Borderline-Hypertonikern zu einer signifikanten Blutdrucksenkung. Während der Studienphase wurden Körpermasse, Natrium-Aufnahme sowie Alkoholzufuhr aufgrund der bekannten Einflussnahme auf den Blutdruck konstant gehalten. In der eigenen Pilot-Studie sollte untersucht werden, ob das Ergebnis der DASH-Studie (i) mit deutschen Hypertonikern und (ii) unter habituellen Ernährungs- und Lebensbedingungen mit regelmäßig durchgeführter Ernährungsberatung und ad libitum Verzehr anstelle des streng kontrollierten Studienansatzes bestätigt werden kann. Eine Konstanz der Körpermasse, der Natrium-Urinausscheidung (unter diesem Studienansatz valider als die Aufnahme) und des Alkoholkonsums wurde vorausgesetzt. Die Studienpopulation setzte sich aus 53 übergewichtigen Probanden mit einer nicht medikamentös therapierten Borderline-Hypertonie und ohne Stoffwechselerkrankungen zusammen. Die Studienteilnehmer wurden randomisiert entweder der Idealgruppe mit einer fettarmen Kost reich an Milchprodukten, Obst und Gemüse (ähnlich der DASH-Idealgruppe) oder der Kontrollgruppe mit habitueller Ernährungsweise zugeteilt. Über einen Zeitraum von fünf Wochen wurde den Probanden etwa 50% ihres täglichen Lebensmittelbedarfes entsprechend ihrer Gruppenzugehörigkeit kostenfrei zur Verfügung gestellt. Gelegenheitsblutdruckmessungen und 24h-Blutdruckmessungen, Ernährungs- und Aktivitätsprotokolle, Blut- und Urinproben sowie anthropometrische Messungen wurden vor, während und fünf Wochen nach der Interventionsphase durchgeführt. Die Ergebnisse zeigen, dass in der Idealgruppe keine signifikante Blutdrucksenkung beobachtet werden konnte. Dies lässt sich durch die Tatsache erklären, dass die Lebens-mittel- und Nährstoffaufnahme der deutschen

  6. Integrating spot short-term measurements of carbon emissions and backward dietary energy partition calculations to estimate intake in lactating dairy cows fed ad libitum or restricted.

    PubMed

    Pereira, A B D; Utsumi, S A; Dorich, C D; Brito, A F

    2015-12-01

    The objective of this study was to use spot short-term measurements of CH4 (QCH4) and CO2 (QCO2) integrated with backward dietary energy partition calculations to estimate dry matter intake (DMI) in lactating dairy cows. Twelve multiparous cows averaging 173±37d in milk and 4 primiparous cows averaging 179±27d in milk were blocked by days in milk, parity, and DMI (as a percentage of body weight) and, within each block, randomly assigned to 1 of 2 treatments: ad libitum intake (AL) or restricted intake (RI=90% DMI) according to a crossover design. Each experimental period lasted 22d with 14d for treatments adaptation and 8d for data and sample collection. Diets contained (dry matter basis): 40% corn silage, 12% grass-legume haylage, and 48% concentrate. Spot short-term gas measurements were taken in 5-min sampling periods from 15 cows (1 cow refused sampling) using a portable, automated, open-circuit gas quantification system (GreenFeed, C-Lock Inc., Rapid City, SD) with intervals of 12h between the 2daily samples. Sampling points were advanced 2h from a day to the next to yield 16 gas samples per cow over 8d to account for diurnal variation in QCH4 and QCO2. The following equations were used sequentially to estimate DMI: (1) heat production (MJ/d)=(4.96 + 16.07 ÷ respiratory quotient) × QCO2; respiratory quotient=0.95; (2) metabolizable energy intake (MJ/d)=(heat production + milk energy) ± tissue energy balance; (3) digestible energy (DE) intake (MJ/d)=metabolizable energy + CH4 energy + urinary energy; (4) gross energy (GE) intake (MJ/d)=DE + [(DE ÷ in vitro true dry matter digestibility) - DE]; and (5) DMI (kg/d)=GE intake estimated ÷ diet GE concentration. Data were analyzed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC) and Fit Model procedure in JMP (α=0.05; SAS Institute Inc.). Cows significantly differed in DMI measured (23.8 vs. 22.4kg/d for AL and RI, respectively). Dry matter intake estimated using QCH4 and QCO2 coupled with

  7. Integrating spot short-term measurements of carbon emissions and backward dietary energy partition calculations to estimate intake in lactating dairy cows fed ad libitum or restricted.

    PubMed

    Pereira, A B D; Utsumi, S A; Dorich, C D; Brito, A F

    2015-12-01

    The objective of this study was to use spot short-term measurements of CH4 (QCH4) and CO2 (QCO2) integrated with backward dietary energy partition calculations to estimate dry matter intake (DMI) in lactating dairy cows. Twelve multiparous cows averaging 173±37d in milk and 4 primiparous cows averaging 179±27d in milk were blocked by days in milk, parity, and DMI (as a percentage of body weight) and, within each block, randomly assigned to 1 of 2 treatments: ad libitum intake (AL) or restricted intake (RI=90% DMI) according to a crossover design. Each experimental period lasted 22d with 14d for treatments adaptation and 8d for data and sample collection. Diets contained (dry matter basis): 40% corn silage, 12% grass-legume haylage, and 48% concentrate. Spot short-term gas measurements were taken in 5-min sampling periods from 15 cows (1 cow refused sampling) using a portable, automated, open-circuit gas quantification system (GreenFeed, C-Lock Inc., Rapid City, SD) with intervals of 12h between the 2daily samples. Sampling points were advanced 2h from a day to the next to yield 16 gas samples per cow over 8d to account for diurnal variation in QCH4 and QCO2. The following equations were used sequentially to estimate DMI: (1) heat production (MJ/d)=(4.96 + 16.07 ÷ respiratory quotient) × QCO2; respiratory quotient=0.95; (2) metabolizable energy intake (MJ/d)=(heat production + milk energy) ± tissue energy balance; (3) digestible energy (DE) intake (MJ/d)=metabolizable energy + CH4 energy + urinary energy; (4) gross energy (GE) intake (MJ/d)=DE + [(DE ÷ in vitro true dry matter digestibility) - DE]; and (5) DMI (kg/d)=GE intake estimated ÷ diet GE concentration. Data were analyzed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC) and Fit Model procedure in JMP (α=0.05; SAS Institute Inc.). Cows significantly differed in DMI measured (23.8 vs. 22.4kg/d for AL and RI, respectively). Dry matter intake estimated using QCH4 and QCO2 coupled with

  8. The Effect of Ad Libitum Consumption of a Milk-Based Liquid Meal Supplement vs. a Traditional Sports Drink on Fluid Balance After Exercise.

    PubMed

    Baguley, Brenton; Zilujko, Jessica; Leveritt, Michael D; Desbrow, Ben; Irwin, Christopher

    2016-08-01

    The aim of this study was to compare the effect of ad libitum intake of a milk-based liquid meal supplement against a carbohydrate-electrolyte sports drink following exercise induced fluid loss. Seven male participants (age 22.3 ± 3.4 years, height 179.3 ± 7.9 cm, body mass 74.3 ± 7.3 kg; mean ± SD) completed 4 separate trials and lost 1.89 ± 0.44% body mass through moderate intensity exercise in the laboratory. After exercise, participants consumed ad libitum over 2 h a milk-based liquid meal supplement (Sustagen Sport) on two of the trials (S1, S2) or a carbohydrate-electrolyte sports drink (Powerade) on two of the trials (P1, P2), with an additional 1 hr observational period. Measures of body mass, urine output, gastrointestinal tolerance and palatability were collected throughout the recovery period. Participants consumed significantly more Powerade than Sustagen Sport over the 2 h rehydration period (P1 = 2225 ± 888 ml, P2 = 2602 ± 1119 mL, S1 = 1375 ± 711 mL, S2 = 1447 ± 857 ml). Total urine output on both Sustagen trails was significantly lower than the second Powerade trial (P2 = 1447 ± 656 ml, S1 = 153 ± 62 ml, S2 = 182 ± 118 mL; p < .05) and trended toward being lower compared with the first Powerade trial (P1 = 1057 ± 699 ml vs. S1, p = .067 and vs. S2, p = .061). No significant differences in net fluid balance were observed between any of the drinks at the conclusion of each trial (P1 = -0.50 ±0. 46 kg, P2 = -0.40 ± 0.35 kg, S1 = -0.61 ± 0.74 kg, S2 = -0.45 ± 0.58 kg). Gastrointestinal tolerance and beverage palatability measures indicated Powerade to be preferred as a rehydration beverage. Ad libitum milk-based liquid meal supplement results in similar net fluid balance as a carbohydrate-electrolyte sports drink after exercise induced fluid loss.

  9. The Effect of Ad Libitum Consumption of a Milk-Based Liquid Meal Supplement vs. a Traditional Sports Drink on Fluid Balance After Exercise.

    PubMed

    Baguley, Brenton; Zilujko, Jessica; Leveritt, Michael D; Desbrow, Ben; Irwin, Christopher

    2016-08-01

    The aim of this study was to compare the effect of ad libitum intake of a milk-based liquid meal supplement against a carbohydrate-electrolyte sports drink following exercise induced fluid loss. Seven male participants (age 22.3 ± 3.4 years, height 179.3 ± 7.9 cm, body mass 74.3 ± 7.3 kg; mean ± SD) completed 4 separate trials and lost 1.89 ± 0.44% body mass through moderate intensity exercise in the laboratory. After exercise, participants consumed ad libitum over 2 h a milk-based liquid meal supplement (Sustagen Sport) on two of the trials (S1, S2) or a carbohydrate-electrolyte sports drink (Powerade) on two of the trials (P1, P2), with an additional 1 hr observational period. Measures of body mass, urine output, gastrointestinal tolerance and palatability were collected throughout the recovery period. Participants consumed significantly more Powerade than Sustagen Sport over the 2 h rehydration period (P1 = 2225 ± 888 ml, P2 = 2602 ± 1119 mL, S1 = 1375 ± 711 mL, S2 = 1447 ± 857 ml). Total urine output on both Sustagen trails was significantly lower than the second Powerade trial (P2 = 1447 ± 656 ml, S1 = 153 ± 62 ml, S2 = 182 ± 118 mL; p < .05) and trended toward being lower compared with the first Powerade trial (P1 = 1057 ± 699 ml vs. S1, p = .067 and vs. S2, p = .061). No significant differences in net fluid balance were observed between any of the drinks at the conclusion of each trial (P1 = -0.50 ±0. 46 kg, P2 = -0.40 ± 0.35 kg, S1 = -0.61 ± 0.74 kg, S2 = -0.45 ± 0.58 kg). Gastrointestinal tolerance and beverage palatability measures indicated Powerade to be preferred as a rehydration beverage. Ad libitum milk-based liquid meal supplement results in similar net fluid balance as a carbohydrate-electrolyte sports drink after exercise induced fluid loss. PMID:26693643

  10. 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.

  11. Postprandial appetite ratings are reproducible and moderately related to total day energy intakes, but not ad libitum lunch energy intakes, in healthy young women.

    PubMed

    Tucker, Amy J; Heap, Sarah; Ingram, Jessica; Law, Marron; Wright, Amanda J

    2016-04-01

    Reproducibility and validity testing of appetite ratings and energy intakes are needed in experimental and natural settings. Eighteen healthy young women ate a standardized breakfast for 8 days. Days 1 and 8, they rated their appetite (Hunger, Fullness, Desire to Eat, Prospective Food Consumption (PFC)) over a 3.5 h period using visual analogue scales, consumed an ad libitum lunch, left the research center and recorded food intake for the remainder of the day. Days 2-7, participants rated their at-home Hunger at 0 and 30 min post-breakfast and recorded food intake for the day. Total area under the curve (AUC) over the 180 min period before lunch, and energy intakes were calculated. Reproducibility of satiety measures between days was evaluated using coefficients of repeatability (CR), coefficients of variation (CV) and intra-class coefficients (ri). Correlation analysis was used to examine validity between satiety measures. AUCs for Hunger, Desire to Eat and PFC (ri = 0.73-0.78), ad libitum energy intakes (ri = 0.81) and total day energy intakes (ri​ = 0.48) were reproducible; fasted ratings were not. Average AUCs for Hunger, Desire to Eat and PFC, Desire to Eat at nadir and PFC at fasting, nadir and 180 min were correlated to total day energy intakes (r = 0.50-0.77, P < 0.05), but no ratings were correlated to lunch consumption. At-home Hunger ratings were weakly reproducible but not correlated to reported total energy intakes. Satiety ratings did not concur with next meal intake but PFC ratings may be useful predictors of intake. Overall, this study adds to the limited satiety research on women and challenges the accepted measures of satiety in an experimental setting. PMID:26763471

  12. Acute effects of mustard, horseradish, black pepper and ginger on energy expenditure, appetite, ad libitum energy intake and energy balance in human subjects.

    PubMed

    Gregersen, N T; Belza, A; Jensen, M G; Ritz, C; Bitz, C; Hels, O; Frandsen, E; Mela, D J; Astrup, A

    2013-02-14

    Chilli peppers have been shown to enhance diet-induced thermogenesis (DIT) and reduce energy intake (EI) in some studies, but there are few data on other pungent spices. The primary aim of the present study was to test the acute effects of black pepper (pepper), ginger, horseradish and mustard in a meal on 4 h postprandial DIT. The secondary aim was to examine the effects on subjective appetite measures, ad libitum EI and energy balance. In a five-way placebo-controlled, single-blind, cross-over trial, twenty-two young (age 24·9 (SD 4·6) years), normal-weight (BMI 21·8 (SD 2·1) kg/m²) males were randomly assigned to receive a brunch meal with either pepper (1·3 g), ginger (20 g), horseradish (8·3 g), mustard (21 g) or no spices (placebo). The amounts of spices were chosen from pre-testing to make the meal spicy but palatable. No significant treatment effects were observed on DIT, but mustard produced DIT, which tended to be larger than that of placebo (14 %, 59 (SE 3) v. 52 (SE 2) kJ/h, respectively, P=0·08). No other spice induced thermogenic effects approaching statistical significance. Subjective measures of appetite (P>0·85), ad libitum EI (P=0·63) and energy balance (P=0·67) also did not differ between the treatments. Finally, horseradish decreased heart rate (P=0·048) and increased diastolic blood pressure (P= 0·049) compared with placebo. In conclusion, no reliable treatment effects on appetite, EI or energy balance were observed, although mustard tended to be thermogenic at this dose. Further studies should explore the possible strength and mechanisms of the potential thermogenic effect of mustard actives, and potential enhancement by, for example, combinations with other food components.

  13. 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.

  14. Effects of dietary vanadium on growth and lipid storage in a larval anuran: results from studies employing ad libitum and rationed feeding.

    PubMed

    Rowe, Christopher L; Heyes, Andrew; Hopkins, William

    2009-01-31

    Vanadium (V) exerts a variety of effects related to metabolic function in vertebrates, including modifying glycolytic pathways and lipid metabolism. However, little is known about toxicity of V to wildlife in natural systems. We conducted parallel, independent studies to evaluate the effect of dietary exposure to vanadium on survival, metabolism, growth, and lipid storage of larval leopard frogs (Rana sphenocephala). In one study ("Ad lib") larvae were fed unlimited food and in the other ("Ration") larvae were fed a restricted diet. Experimental diets contained 10 ppm dw V(total) (Control, "C"), 109 ppm (Low, "L"), and 363 ppm (High, "H"). In neither study did V affect metabolic rate or survival to forelimb emergence. However, in the Ration study, 31% of individuals in H that had initiated metamorphosis died prior to completion of metamorphosis, compared with 22% in M and 9% in C, however the difference was not significant at alpha=0.05. Mortality during metamorphosis in the Ad lib study was more variable, yet followed a similar trend (26, 14, and 12% mortality in H, L, and C). In both studies, individuals that died during the metamorphic period were smaller at the time of forelimb emergence than those that survived. In the Ration study, individuals in H also had significantly lower growth rates, delayed metamorphosis, and reduced lipid content at metamorphosis compared to C and L. Growth was not affected by V in the Ad lib study. Our results suggest that habitat contamination by V may present risks to amphibians during the metamorphic period attributable to energetic responses influencing size at the initiation of metamorphosis and body lipid stores. Furthermore, while we cannot make formal comparisons between the studies, our results imply that protocols that employ ad libitum feeding regimes could fail to capture the effects of contaminants as they may be expressed in natural situations in which resources are typically more limited.

  15. 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

  16. 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

  17. 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

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

    PubMed

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

    2015-08-01

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

  19. Effects of Dietary Protein and Fiber at Breakfast on Appetite, ad Libitum Energy Intake at Lunch, and Neural Responses to Visual Food Stimuli in Overweight Adults

    PubMed Central

    Sayer, R. Drew; Amankwaah, Akua F.; Tamer, Gregory G.; Chen, Ningning; Wright, Amy J.; Tregellas, Jason R.; Cornier, Marc-Andre; Kareken, David A.; Talavage, Thomas M.; McCrory, Megan A.; Campbell, Wayne W.

    2016-01-01

    Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/m2; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults. PMID:26742068

  20. Effects of Dietary Protein and Fiber at Breakfast on Appetite, ad Libitum Energy Intake at Lunch, and Neural Responses to Visual Food Stimuli in Overweight Adults.

    PubMed

    Sayer, R Drew; Amankwaah, Akua F; Tamer, Gregory G; Chen, Ningning; Wright, Amy J; Tregellas, Jason R; Cornier, Marc-Andre; Kareken, David A; Talavage, Thomas M; McCrory, Megan A; Campbell, Wayne W

    2016-01-01

    Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/m²; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults.

  1. Effects of Dietary Protein and Fiber at Breakfast on Appetite, ad Libitum Energy Intake at Lunch, and Neural Responses to Visual Food Stimuli in Overweight Adults.

    PubMed

    Sayer, R Drew; Amankwaah, Akua F; Tamer, Gregory G; Chen, Ningning; Wright, Amy J; Tregellas, Jason R; Cornier, Marc-Andre; Kareken, David A; Talavage, Thomas M; McCrory, Megan A; Campbell, Wayne W

    2016-01-01

    Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/m²; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults. PMID:26742068

  2. Exercise and food ad libitum reduce the impact of early in life nutritional inbalances on nitrergic activity of hippocampus and striatum.

    PubMed

    Viana, Lane Coelho; Torres, João Bento; Farias, José Augusto; Kawhage, Rafael; Lins, Nara; Passos, Aline; Quintairos, Amanda; Trévia, Nonata; Guedes, Rubem Carlos Araújo; Diniz, Cristovam Wanderley Picanço

    2007-01-01

    Nutritional imbalances were produced by varying litter size pups per dam: 3 (small), 6 (medium), and 12 (large). On the 21st day, 4 subjects of each litter, were sacrificed and the remaining were grouped, 2 per cage, with or without running wheels, with food and water ad libitum. Adult subjects were tested in water maze, their brains processed for NADPH-diaphorase histochemistry and quantified by densitometry. No differences were detected in water maze. At 21st day, S and L compared with M presented reduced NADPH-d in the stratum molecular of dentate gyrus (DG), stratum lacunosum of CA1 and in all CA3 layers but not in the striatum. On the 58th day, actvity remained low in S and L in CA3 and striatum and L in CA1 and DG. Voluntary exercise increased NADPH-d in DG, CA1, CA3, and striatum in S, and in the stratum lacunosum of CA1 and CA3 in L.

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

    PubMed Central

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

    2016-01-01

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

  4. Manganese-enhanced magnetic resonance imaging for mapping of whole brain activity patterns associated with the intake of snack food in ad libitum fed rats.

    PubMed

    Hoch, Tobias; Kreitz, Silke; Gaffling, Simone; Pischetsrieder, Monika; Hess, Andreas

    2013-01-01

    Non-homeostatic hyperphagia, which is a major contributor to obesity-related hyperalimentation, is associated with the diet's molecular composition influencing, for example, the energy content. Thus, specific food items such as snack food may induce food intake independent from the state of satiety. To elucidate mechanisms how snack food may induce non-homeostatic food intake, it was tested if manganese-enhanced magnetic resonance imaging (MEMRI) was suitable for mapping the whole brain activity related to standard and snack food intake under normal behavioral situation. Application of the MnCl2 solution by osmotic pumps ensured that food intake was not significantly affected by the treatment. After z-score normalization and a non-affine three-dimensional registration to a rat brain atlas, significantly different grey values of 80 predefined brain structures were recorded in ad libitum fed rats after the intake of potato chips compared to standard chow at the group level. Ten of these areas had previously been connected to food intake, in particular to hyperphagia (e.g., dorsomedial hypothalamus or the anterior paraventricular thalamic nucleus) or to the satiety system (e.g., arcuate hypothalamic nucleus or solitary tract); 27 areas were related to reward/addiction including the core and shell of the nucleus accumbens, the ventral pallidum and the ventral striatum (caudate and putamen). Eleven areas associated to sleep displayed significantly reduced Mn2+ -accumulation and six areas related to locomotor activity showed significantly increased Mn2+ -accumulation after the intake of potato chips. The latter changes were associated with an observed significantly higher locomotor activity. Osmotic pump-assisted MEMRI proved to be a promising technique for functional mapping of whole brain activity patterns associated to nutritional intake under normal behavior. PMID:23408973

  5. The effect of an incremental increase in exercise on appetite, eating behaviour and energy balance in lean men and women feeding ad libitum.

    PubMed

    Whybrow, Stephen; Hughes, Darren A; Ritz, Patrick; Johnstone, Alexandra M; Horgan, Graham W; King, Neil; Blundell, John E; Stubbs, R James

    2008-11-01

    The effects of incremental exercise on appetite, energy intake (EI), expenditure (EE) and balance (EB) in lean men and women were examined. Six men (age 29.7 (SD 5.9) years, weight 75.2 (SD 15.3) kg, height 1.75 (SD 0.11) m) and six women (age 24.7 (SD 5.9) years, weight 66.7 (SD 9.10) kg, height 1.70 (SD 0.09) m) were each studied three times during a 16 d protocol, corresponding to no additional exercise (Nex), moderate-intensity exercise (Mex; 1.5-2.0 MJ/d) and high-intensity exercise (Hex; 3.0-4.0 MJ/d) regimens. Subjects were fed to EB during days 1-2, and during days 3-16 they fed ad libitum from a medium-fat diet of constant composition. Daily EE, assessed using the doubly labelled water method, was 9.2, 11.6 and 13.7 MJ/d (P < 0.001; SED 0.45) for the women and 12.2, 14.0 and 16.7 MJ/d (P = 0.007; SED 1.11) for the men on the Nex, Mex and Hex treatments, respectively. EI was 8.3, 8.6 and 9.9 MJ/d (P = 0.118; SED 0.72) for the women and 10.6, 11.6 and 12.0 MJ/d (P = 0.031; SED 0.47) for the men, respectively. On average, subjects compensated for about 30 % of the exercise-induced energy deficit. However, the degree of compensation varied considerably among individuals. The present study captured the initial compensation in EI for exercise-induced energy deficits. Total compensation would take a matter of weeks.

  6. Does Increased Exercise or Physical Activity Alter Ad-Libitum Daily Energy Intake or Macronutrient Composition in Healthy Adults? A Systematic Review

    PubMed Central

    Donnelly, Joseph E.; Herrmann, Stephen D.; Lambourne, Kate; Szabo, Amanda N.; Honas, Jeffery J.; Washburn, Richard A.

    2014-01-01

    Background The magnitude of the negative energy balance induced by exercise may be reduced due to compensatory increases in energy intake. Objective To address the question: Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? Data Sources PubMed and Embase were searched (January 1990–January 2013) for studies that presented data on energy and/or macronutrient intake by level of exercise, physical activity or change in response to exercise. Ninety-nine articles (103 studies) were included. Study Eligibility Criteria Primary source articles published in English in peer-reviewed journals. Articles that presented data on energy and/or macronutrient intake by level of exercise or physical activity or changes in energy or macronutrient intake in response to acute exercise or exercise training in healthy (non-athlete) adults (mean age 18–64 years). Study Appraisal and Synthesis Methods Articles were grouped by study design: cross-sectional, acute/short term, non-randomized, and randomized trials. Considerable heterogeneity existed within study groups for several important study parameters, therefore a meta-analysis was considered inappropriate. Results were synthesized and presented by study design. Results No effect of physical activity, exercise or exercise training on energy intake was shown in 59% of cross-sectional studies (n = 17), 69% of acute (n = 40), 50% of short-term (n = 10), 92% of non-randomized (n = 12) and 75% of randomized trials (n = 24). Ninety-four percent of acute, 57% of short-term, 100% of non-randomized and 74% of randomized trials found no effect of exercise on macronutrient intake. Forty-six percent of cross-sectional trials found lower fat intake with increased physical activity. Limitations The literature is limited by the lack of adequately powered trials of sufficient duration, which have prescribed and measured exercise energy expenditure

  7. Differential effects of methamphetamine on expression of neuropeptide Y mRNA in hypothalamus and on serum leptin and ghrelin concentrations in ad libitum-fed and schedule-fed rats.

    PubMed

    Crowley, W R; Ramoz, G; Keefe, K A; Torto, R; Kalra, S P; Hanson, G R

    2005-01-01

    Relatively little is known concerning the interaction of psychostimulants with hypothalamic neuropeptide systems or metabolic hormones implicated in regulation of energy balance. The present studies tested whether methamphetamine alters the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP), two important orexigenic neuropeptides, or proopiomelanocortin (POMC), the precursor for the anorexigenic peptide alpha-melanocyte-stimulating hormone, or the secretion of leptin, insulin and ghrelin, concomitant with inhibition of food intake. Female rats were either fed ad libitum (AL) or placed on a scheduled feeding (SF) regimen, with access to food limited to 4 h/day. Administration of (+/-)-methamphetamine (7.5 mg/kg, i.p.) 2 h prior to food presentation significantly inhibited food intake in SF animals, but did not affect intake in AL animals. In a separate study, AL and SF animals were killed just prior to expected food presentation, and expression of NPY, AgRP and POMC mRNAs in hypothalamus was determined using in situ hybridisation; concentrations of leptin, insulin and ghrelin in serum were determined with radioimmunoassays. In saline-treated, SF controls, NPY and AgRP mRNA expression in arcuate nucleus and serum ghrelin were significantly elevated, and serum leptin and insulin were significantly reduced. Methamphetamine reversed the up-regulation of NPY mRNA expression observed in the SF condition, without affecting AgRP mRNA or the serum concentrations of metabolic hormones. However, in AL animals, NPY mRNA expression in arcuate and dorsomedial nuclei was significantly increased by methamphetamine, which also reduced serum leptin and insulin and increased serum ghrelin concentrations. These findings suggest that the inhibition of NPY expression in SF animals may be a mechanism underlying the anorexigenic effect of methamphetamine seen in this condition. The increase in NPY expression produced by methamphetamine in AL animals may be mediated by the

  8. Effect of CSN1S1 genotype and its interaction with diet energy level on milk production and quality in Girgentana goats fed ad libitum.

    PubMed

    Pagano, Renato Italo; Pennisi, Pietro; Valenti, Bernardo; Lanza, Massimiliano; Di Trana, Adriana; Di Gregorio, Paola; De Angelis, Anna; Avondo, Marcella

    2010-05-01

    A study was carried out to evaluate how the energy level of the diet can affect milk production and quality in Girgentana lactating goats in relation to polymorphism at the alphas1-casein (CSN1S1) genotype locus. Twenty-seven goats, homogeneous for milk production (1.5+/-0.3 kg/d), days of lactation (90+/-10 d) and body weight (35.8+/-5.5 kg) were selected on the basis of their CSN1S1 genotype, as follows: nine goats homozygous for strong (AA) alleles, nine goats homozygous for weak alleles (FF) and nine goats heterozygous (AF). The goats were used in a 3x3 factorial arrangement of treatments, with three genotypes (AA, FF, AF) and three diets at different energy levels (100%, 65% and 30% of hay inclusion). The experiment consisted of three simultaneous 3x3 Latin squares for the three genotypes, with one square for each level of hay inclusion in the diet. All the animals were housed in individual pens. Each experimental period lasted 23 d and consisted of 15 d for adaptation and 8 d for data and sample collection, during which the goats received the scheduled diet ad libitum. The animals were fed three different diets designed to have the same crude protein content (about 15%) but different energy levels: a pelleted alfalfa hay (H100) and two feeds including 65% (H65) and 30% (H30) of alfalfa hay (respectively 1099, 1386 and 1590 kcal NE for lactation/kg DM). All the diets were ground and pelleted (6 mm diameter). AA goats were more productive than AF and FF goats (respectively: 1419 v. 1145 and 1014 g/d; P=0.002). Indeed the interaction energy levelxgenotype was significant (P=0.018): in fact AA goats showed their milk increase only when fed with concentrates. Differences in protein and in casein levels between the three genotypes were in line with results expected from the different allele contribution to alphas1-casein synthesis. Milk urea levels were significantly lower in AA goats compared with AF and FF genotypes (respectively 32.7 v. 40.4 and 40.4 mg/dl; P=0

  9. Long-term effects of ad libitum whole milk prior to weaning and prepubertal protein supplementation on skeletal growth rate and first-lactation milk production.

    PubMed

    Moallem, U; Werner, D; Lehrer, H; Zachut, M; Livshitz, L; Yakoby, S; Shamay, A

    2010-06-01

    Our objectives were to determine the effects of rapid growth rate during the preweaning period and prepubertal protein supplementation on long-term growth pattern and milk production during the first lactation. Forty-six Israeli Holstein heifer calves were fed either milk replacer (MR) or whole milk (WM) from 4 to 60 d age. Calves had free access to WM or MR for 30 min twice daily and free-choice water and starter mix for the entire day. From weaning until 150 d of age, all heifers were fed the same ration. At 150 d of age the heifers were divided into 2 subgroups, with one subgroup supplemented with an additional 2% protein until 320 d of age. Thereafter, all heifers were housed and fed together until calving. Another cluster of 20 heifers was raised on MR and WM treatments and 3 animals from each nursery treatment were slaughtered at 60 d and 10 mo age to determine effects of nursery treatment on organ and adipose tissue mass. Prior to weaning, the MR heifers consumed 0.12 kg/d more DM than the WM heifers, but metabolizable energy intake was not different. Body weight at weaning and average daily gain during the preweaning period were 3.1 kg and 0.074 kg/d higher, respectively, in the WM treatment than in the MR treatment, with no differences in other measurements. Nursery feeding treatment and added protein had no effect on growth rate in the prepubertal period, but the postweaning difference in BW between the WM and MR heifers remained throughout the entire rearing period. The age at first insemination was 23 d earlier and age at pregnancy and first calving was numerically lower for the WM heifers than for the MR heifers. Adipose tissue weights at weaning were doubled in the WM calves. First-lactation milk production and 4% fat-corrected milk were 10.3 and 7.1% higher, respectively, for WM heifers than for MR heifers, whereas prepubertal added protein tended to increase milk yield. In conclusion, preweaning WM at high feeding rates appears to have long

  10. Short communication: Use of a portable, automated, open-circuit gas quantification system and the sulfur hexafluoride tracer technique for measuring enteric methane emissions in Holstein cows fed ad libitum or restricted.

    PubMed

    Dorich, C D; Varner, R K; Pereira, A B D; Martineau, R; Soder, K J; Brito, A F

    2015-04-01

    The objective of this study was to measure enteric CH4 emissions using a new portable automated open-circuit gas quantification system (GQS) and the sulfur hexafluoride tracer technique (SF6) in midlactation Holstein cows housed in a tiestall barn. Sixteen cows averaging 176 ± 34 d in milk, 40.7 ± 6.1 kg of milk yield, and 685 ± 49 kg of body weight were randomly assigned to 1 out of 2 treatments according to a crossover design. Treatments were (1) ad libitum (adjusted daily to yield 10% orts) and (2) restricted feed intake [set to restrict feed by 10% of baseline dry matter intake (DMI)]. Each experimental period lasted 22d, with 14 d for treatment adaptation and 8d for data and sample collection. A common diet was fed to the cows as a total mixed ration and contained 40.4% corn silage, 11.2% grass-legume haylage, and 48.4% concentrate on a dry matter basis. Spot 5-min measurements using the GQS were taken twice daily with a 12-h interval between sampling and sampling times advanced 2h daily to account for diurnal variation in CH4 emissions. Canisters for the SF6 method were sampled twice daily before milking with 4 local background gas canisters inside the barn analyzed for background gas concentrations. Enteric CH4 emissions were not affected by treatments and averaged 472 and 458 g/d (standard error of the mean = 18 g/d) for ad libitum and restricted intake treatments, respectively (data not shown). The GQS appears to be a reliable method because of the relatively low coefficients of variation (ranging from 14.1 to 22.4%) for CH4 emissions and a moderate relationship (coefficient of determination = 0.42) between CH4 emissions and DMI. The SF6 resulted in large coefficients of variation (ranging from 16.0 to 111%) for CH4 emissions and a poor relationship (coefficient of determination = 0.17) between CH4 emissions and DMI, likely because of limited barn ventilation and high background gas concentration. Research with improved barn ventilation systems or

  11. Short communication: Use of a portable, automated, open-circuit gas quantification system and the sulfur hexafluoride tracer technique for measuring enteric methane emissions in Holstein cows fed ad libitum or restricted.

    PubMed

    Dorich, C D; Varner, R K; Pereira, A B D; Martineau, R; Soder, K J; Brito, A F

    2015-04-01

    The objective of this study was to measure enteric CH4 emissions using a new portable automated open-circuit gas quantification system (GQS) and the sulfur hexafluoride tracer technique (SF6) in midlactation Holstein cows housed in a tiestall barn. Sixteen cows averaging 176 ± 34 d in milk, 40.7 ± 6.1 kg of milk yield, and 685 ± 49 kg of body weight were randomly assigned to 1 out of 2 treatments according to a crossover design. Treatments were (1) ad libitum (adjusted daily to yield 10% orts) and (2) restricted feed intake [set to restrict feed by 10% of baseline dry matter intake (DMI)]. Each experimental period lasted 22d, with 14 d for treatment adaptation and 8d for data and sample collection. A common diet was fed to the cows as a total mixed ration and contained 40.4% corn silage, 11.2% grass-legume haylage, and 48.4% concentrate on a dry matter basis. Spot 5-min measurements using the GQS were taken twice daily with a 12-h interval between sampling and sampling times advanced 2h daily to account for diurnal variation in CH4 emissions. Canisters for the SF6 method were sampled twice daily before milking with 4 local background gas canisters inside the barn analyzed for background gas concentrations. Enteric CH4 emissions were not affected by treatments and averaged 472 and 458 g/d (standard error of the mean = 18 g/d) for ad libitum and restricted intake treatments, respectively (data not shown). The GQS appears to be a reliable method because of the relatively low coefficients of variation (ranging from 14.1 to 22.4%) for CH4 emissions and a moderate relationship (coefficient of determination = 0.42) between CH4 emissions and DMI. The SF6 resulted in large coefficients of variation (ranging from 16.0 to 111%) for CH4 emissions and a poor relationship (coefficient of determination = 0.17) between CH4 emissions and DMI, likely because of limited barn ventilation and high background gas concentration. Research with improved barn ventilation systems or

  12. Metabolic determinants of body weight after cats were fed a low-carbohydrate high-protein diet or a high-carbohydrate low-protein diet ad libitum for 8 wk.

    PubMed

    Coradini, M; Rand, J S; Morton, J M; Rawlings, J M

    2014-10-01

    Overweight and obese conditions are common in cats and are associated with the development of a number of diseases. Knowledge of metabolic determinants and predictors of weight gain may enable better preventative strategies for obesity in cats. Lean, healthy cats were fed either a low-carbohydrate high-protein diet (n 16) or a high-carbohydrate low-protein (n 16) diet ad libitum for 8 wk. Potential determinants and predictors of final body weight assessed were body fat and lean masses, energy required for maintenance, energy requirements above maintenance for each kilogram of weight gain, insulin sensitivity index, fasting, mean 24-h and peak plasma glucose, insulin, and leptin concentrations, and fasting and mean 24-h serum adiponectin concentrations. In cats fed the low-carbohydrate high-protein diet, after adjusting for initial body weight, those with higher energy requirements for weight gain and higher fasting glucose concentration had higher final body weights (P ≤ 0.01). Predicted final body weights using initial body weight, fasting glucose and mean 24-h insulin concentrations (partial R(2) 37.3%) were imprecise. An equation using just initial body weight and fasting glucose concentration would be of more practical value, but was marginally less precise. In cats fed the high-carbohydrate low-protein diet, those with lower fasting leptin concentration initially had higher final body weights (P = 0.01). Predicted final body weights using initial body weight, energy requirements for maintenance, total body fat percentage and fasting leptin concentration (partial R(2) 39.2%) were reasonably precise. Further studies are warranted to confirm these findings and to improve the precision of predicted final body weights. PMID:25084314

  13. Metabolic determinants of body weight after cats were fed a low-carbohydrate high-protein diet or a high-carbohydrate low-protein diet ad libitum for 8 wk.

    PubMed

    Coradini, M; Rand, J S; Morton, J M; Rawlings, J M

    2014-10-01

    Overweight and obese conditions are common in cats and are associated with the development of a number of diseases. Knowledge of metabolic determinants and predictors of weight gain may enable better preventative strategies for obesity in cats. Lean, healthy cats were fed either a low-carbohydrate high-protein diet (n 16) or a high-carbohydrate low-protein (n 16) diet ad libitum for 8 wk. Potential determinants and predictors of final body weight assessed were body fat and lean masses, energy required for maintenance, energy requirements above maintenance for each kilogram of weight gain, insulin sensitivity index, fasting, mean 24-h and peak plasma glucose, insulin, and leptin concentrations, and fasting and mean 24-h serum adiponectin concentrations. In cats fed the low-carbohydrate high-protein diet, after adjusting for initial body weight, those with higher energy requirements for weight gain and higher fasting glucose concentration had higher final body weights (P ≤ 0.01). Predicted final body weights using initial body weight, fasting glucose and mean 24-h insulin concentrations (partial R(2) 37.3%) were imprecise. An equation using just initial body weight and fasting glucose concentration would be of more practical value, but was marginally less precise. In cats fed the high-carbohydrate low-protein diet, those with lower fasting leptin concentration initially had higher final body weights (P = 0.01). Predicted final body weights using initial body weight, energy requirements for maintenance, total body fat percentage and fasting leptin concentration (partial R(2) 39.2%) were reasonably precise. Further studies are warranted to confirm these findings and to improve the precision of predicted final body weights.

  14. Twin Roll Casting of Al-Mg Alloy with High Added Impurity Content

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Hari Babu, N.; Scamans, G. M.; Fan, Z.; O'Reilly, K. A. Q.

    2014-06-01

    The microstructural evolution during twin roll casting (TRC) and downstream processing of AA5754 Al alloy with high added impurity content have been investigated. Strip casts with a high impurity content resulted in coarse α-Al grains and complex secondary phases. The grain size and centerline segregation reduced significantly on the addition of Al-Ti-B grain refiner (GR). Coarse-dendrite arm spacing (DAS) "floating" grains are observed in the impure alloy (IA) with higher volume in the GR strips. Two-dimensional (2D) metallographic analysis of the as-cast strip suggests that secondary phases (Fe-bearing intermetallics and Mg2Si) are discrete and located at the α-Al cell/grain boundaries, while three-dimensional (3D) analysis of extracted particles revealed that they were intact, well interconnected, and located in interdendritic regions. Homogenizing heat treatment of the cast strip breaks the interconnective networks and modifies the secondary phases to a more equiaxed morphology. During rolling, the equiaxed secondary phases align along the rolling direction. X-ray diffraction (XRD) analysis suggests that α-Al(FeMn)Si and Mg2Si are the predominant secondary phases that are formed during casting and remain throughout the downstream processing of the GR-IA. The high-impurity sheet processed from TRC resulted in superior strength and ductility over the sheet processed from small book mold ingot casting. The current study has shown that the TRC process can tolerate higher impurity levels and produce formable sheets from the recycled aluminum for structural applications.

  15. Surgery for Gynecomastia in the Islamic Golden Age: Al-Tasrif of Al-Zahrawi (936–1013 AD)

    PubMed Central

    Chavoushi, Seyed Hadi; Ghabili, Kamyar; Kazemi, Abdolhassan; Aslanabadi, Arash; Babapour, Sarah; Ahmedli, Rafail; Golzari, Samad E. J.

    2012-01-01

    The rise of European science during the Renaissance is greatly indebted to the flourishing of the sciences during the Islamic Golden Age. However, some believe that medieval Islamic physicians and in particular surgeons had been merely a medium for Greco-Roman ideas. Contrarily, in some medieval Islamic medical books, such as Al-Tasrif of Al-Zahrawi (936–1013), the surgical instructions represent a change in the usual techniques or are accompanied by a case history, implying that the procedure was actually undertaken. Along with the hundreds of chapters on different diseases and related medical and surgical treatments, Al-Tasrif includes a chapter on surgical techniques for gynecomastia. The present paper is a review of the description of the surgical management of gynecomastia by Al-Zahrawi as well as that of the ancient Greek, medieval, and modern medicine. Although Al-Zahrawi seemed to base his descriptions of surgery for gynecomastia upon those of Paulus of Aegina, his modification of the procedure and application of the medicinal substances might be indicative of Al-Zahrawi's own practice of the procedure. Al-Zahrawi's surgical procedures remained unchanged for many centuries thenceforward until the technological evolution in the recent centuries. PMID:23050167

  16. YAG laser surface densification of a zircon refractory by adding AlN nanoparticles

    SciTech Connect

    Wang, W.Y.; Wang, A.H. . E-mail: pmahwang@public.wh.hb.cn; Zeng, D.W.; Bai, Z.K.; Xie, C.S.; Song, W.L.; Zhu, X.C.

    2006-04-15

    A zircon refractory zirconium silicate was surface melted with a pulsed YAG laser to introduce AlN nanoparticles, with the aim of improving its surface density and modifying the corresponding microstructure. The microstructure and phase structure features of the refractory induced by the laser beam were studied by scanning transmission microscopy, incorporating energy dispersive X-ray and X-ray diffraction analysis. Results show that the addition of AlN nanoparticles into the refractory surface significantly reduced the laser beam energy required to melt the surface of the refractory. The laser-melted depth was increased with an increase of laser power from 133 to 200 W. The microstructure of the laser-treated zone with the addition of AlN nanoparticles has a much finer dendritic structure with undeveloped primary dendrite arms while without the addition of AlN nanoparticles, a coarser dendrite with much long primary dendrite arms was observed. The phase structure of the laser-treated layer with the addition of AlN nanoparticles was found to be composed of m-ZrO{sub 2}, c-ZrO{sub 2}, ZrSiO{sub 4} and H-AlN.

  17. Catalytic hydrothermal conversion of carboxymethyl cellulose to value-added chemicals over metal-organic framework MIL-53(Al).

    PubMed

    Zi, Guoli; Yan, Zhiying; Wang, Yangxia; Chen, Yongjuan; Guo, Yunlong; Yuan, Fagui; Gao, Wenyu; Wang, Yanmei; Wang, Jiaqiang

    2015-01-22

    Catalytic hydrolysis of biomass over solid catalysts can be one of the most efficient pathways for a future sustainable society dependent on cellulose biomass. In this work metal-organic framework MIL-53(Al) without any functionalization was directly employed as an efficient heterogeneous catalyst for the hydrolysis of carboxymethyl cellulose (CMC) to 5-hydroxymethyl-furaldehyde (5-HMF) in aqueous phase. A 5-HMF molar yield of 40.3% and total reducing sugar (TRS) molar yield of 54.2% were obtained with water as single solvent at 473 K for 4 h. The catalyst could be reused three times without losing activity to a greater extent. With the remarkable advantages such as the use of water as single solvent and MIL-53(Al) as a novel heterogeneous green catalyst, the work provides a new platform for the production of value added chemicals and liquid fuels from biomass. PMID:25439879

  18. The construction of fertility in al-Andalus. Geoarchaeology in Ricote (Murcia, Spain, 8th century AD)

    NASA Astrophysics Data System (ADS)

    Puy, Arnald

    2013-04-01

    Traditional irrigated terraces of Spain (known as 'huertas') are among the most emblematic and productive agricultural fields of the Mediterranean. Several of these huertas were first built by Arab and Berber tribes and clans that entered the Iberian Peninsula (al-Andalus) after 711 AD, coinciding with the spread of Islam during Middle Ages (>632 AD). One thousand and three hundred years after their construction they are still operative, presenting a topic case of sustainable and resilient agricultural areas. However, up until recently no data was available regarding the pre-existing features of the terrains where they were built, the timing of their construction nor their construction process. In this communication I will present the results of the study of a palaeosoil buried under an Andalusi irrigated terrace in the huerta of Ricote (Murcia, Spain). Soil micromorphology, physico-chemical analysis (Loss On Ignition, Magnetic Susceptibility, Particle Size Distribution, pH/Electrical Conductivity) and AMS dating allowed to determine that 1) Andalusi peasants selected a highly saline Hypercalcic Calcisol to build up the first irrigated terraces; 2) They clear the slope of bushes by fire; 3) They used the slope soil to build the terrace fill, possibly by inverting the original soil horizonation, and 4) According to the date obtained from the organic matter embedded in the topmost horizon of the palaeosoil (647-778 AD), the original Andalusi irrigated fields of Ricote were possibly built shortly after 711 AD. The communication, in sum, will show through a case study how past peasant societies transformed semi-arid environments to create highly productive agrarian areas.

  19. A transient event in AD 775 reported by al-Tabarı: A bolide - not a nova, supernova, or kilonova

    NASA Astrophysics Data System (ADS)

    Neuhäuser, R.; Kunitzsch, P.

    2014-11-01

    Given that the cause for the strong increase in 14C in AD 774/5 in Japanese and German trees is still a matter of debate (e.g. short gamma-ray burst or solar super-flare), we have searched in Arabic chronicles for reports about unusual transient celestial events. In the History of al-Tabarı we found two (almost identical) reports about such an event. The group around caliph al-Mansūr observed a transient event while on the way from Baghdad to Mecca on AD 775 Augusst 29 - September 1 (Julian calendar). A celestial object (kawkab) was seen to fall or set (inqadda), and its trace (atharuhu) was seen for at least tens of minutes (up to 70-90 min) during morning twilight. The reports use the Arabic words kawkab and athar(uhu), which were also used in the known Arabic reports about supernovae SN 1006 and 1054, so that one might consider an interpretation as a nova-like event. The kawkab (celestial object) was observed only during the morning twilight at a brightness of probably between about -3 and 0 mag. Such a brightness and time-scale would be expected for optical kilonovae (at {˜ 3} to 9 kpc) in the context of short gamma-ray bursts. There are no similar reports from eastern Asia for this time. However, the short reports are fully consistent with a bolide: The word kawkab can be used for meteor, the verb inqadda normally means falling down, the word atharuhu can mean its trace. We therefore prefer the interpretation as bolide. We discuss in detail how to convert the Muslim calendar date to a date in the Julian calendar using first the calculated Islamic calendar and then considering the time when the crescent new moon could be visible at the given location.

  20. Improved single pellet grasping using automated ad libitum full-time training robot.

    PubMed

    Fenrich, Keith K; May, Zacnicte; Hurd, Caitlin; Boychuk, Carolyn E; Kowalczewski, Jan; Bennett, David J; Whishaw, Ian Q; Fouad, Karim

    2015-03-15

    The single pellet grasping (SPG) task is a skilled forelimb motor task commonly used to evaluate reaching and grasp kinematics and recovery of forelimb function in rodent models of CNS injuries and diseases. To train rats in the SPG task, the animals are usually food restricted then placed in an SPG task enclosure and presented food pellets on a platform located beyond a slit located at the front of the task enclosure for 10-30 min, normally every weekday for several weeks. When the SPG task is applied in studies involving various experimental groups, training quickly becomes labor intensive, and can yield results with significant day-to-day variability. Furthermore, training is frequently done during the animals' light-cycle, which for nocturnal rodents such as mice and rats could affect performance. Here we describe an automated pellet presentation (APP) robotic system to train and test rats in the SPG task that reduces some of the procedural weaknesses of manual training. We found that APP trained rats performed significantly more trials per 24 h period, and had higher success rates with less daily and weekly variability than manually trained rats. Moreover, the results show that success rates are positively correlated with the number of dark-cycle trials, suggesting that dark-cycle training has a positive effect on success rates. These results demonstrate that automated training is an effective method for evaluating and training skilled reaching performance of rats, opening up the possibility for new approaches to investigating the role of motor systems in enabling skilled forelimb use and new approaches to investigating rehabilitation following CNS injury. PMID:25523027

  1. Improved single pellet grasping using automated ad libitum full-time training robot.

    PubMed

    Fenrich, Keith K; May, Zacnicte; Hurd, Caitlin; Boychuk, Carolyn E; Kowalczewski, Jan; Bennett, David J; Whishaw, Ian Q; Fouad, Karim

    2015-03-15

    The single pellet grasping (SPG) task is a skilled forelimb motor task commonly used to evaluate reaching and grasp kinematics and recovery of forelimb function in rodent models of CNS injuries and diseases. To train rats in the SPG task, the animals are usually food restricted then placed in an SPG task enclosure and presented food pellets on a platform located beyond a slit located at the front of the task enclosure for 10-30 min, normally every weekday for several weeks. When the SPG task is applied in studies involving various experimental groups, training quickly becomes labor intensive, and can yield results with significant day-to-day variability. Furthermore, training is frequently done during the animals' light-cycle, which for nocturnal rodents such as mice and rats could affect performance. Here we describe an automated pellet presentation (APP) robotic system to train and test rats in the SPG task that reduces some of the procedural weaknesses of manual training. We found that APP trained rats performed significantly more trials per 24 h period, and had higher success rates with less daily and weekly variability than manually trained rats. Moreover, the results show that success rates are positively correlated with the number of dark-cycle trials, suggesting that dark-cycle training has a positive effect on success rates. These results demonstrate that automated training is an effective method for evaluating and training skilled reaching performance of rats, opening up the possibility for new approaches to investigating the role of motor systems in enabling skilled forelimb use and new approaches to investigating rehabilitation following CNS injury.

  2. Effects of Properties on S45C Carbon Steel by Electroless NiP Adding Al2O3 Powder of Composite Deposition and Various Heat Treatments

    NASA Astrophysics Data System (ADS)

    Chang, Shih-Hsien; Liang, Cheng; Chang, Chih-Chung

    2014-06-01

    This research studies the effects on the surface microstructure and mechanical properties of S45C carbon steel via electroless Ni-P, by adding αAl2O3 powder via composite deposition and various heat treatments. The plating specimens were treated with pH5 and pH8 baths heated to 350°C and 300°C, respectively, and soaked for 1 hr. Meanwhile, two different particle sizes of Al2O3 powder were added to the electroless Ni-P plating: 0.3 μm of αAl2O3 and 0.05 μm of γAl2O3 powder, respectively. The experimental results show that, after 1 hr of heat treatment at 300°C, the optimal hardness for the specimens using the pH8 of Ni-P with αAl2O3 and γAl2O3 added by composite deposition are HV0.05 1237 and HV0.05 1145, respectively. All of the specimens underwent the main precipitate phase of Ni3P after heat treatment.

  3. A fresh insight into the evolutionary status and third body hypothesis of the eclipsing binaries AD Andromedae, AL Camelopardalis, and V338 Herculis

    NASA Astrophysics Data System (ADS)

    Liakos, A.; Niarchos, P.; Budding, E.

    2012-03-01

    Aims: We aim to derive the absolute parameters of the components of AD And, AL Cam, and V338 Her, interpret their orbital period changes and discuss their evolutionary status. Methods: New and complete multi-filter light curves of the eclipsing binaries AD And, AL Cam, and V338 Her were obtained and analysed with modern methods. Using all reliably observed times of minimum light, we examined orbital period irregularities using the least squares method. In addition, we acquired new spectroscopic observations during the secondary eclipses for AL Cam and V338 Her. Results: For AL Cam and V338 Her, we derive reliable spectral types for their primary stars. Statistical checks of orbital period analysis for all systems are very reassuring in the cases of V338 Her and AD And, although less so for AL Cam. The LIght-Time Effect (LITE) results are checked by inclusion of a third light option in the photometric analyses. Light curve solutions provide the means to calculate the absolute parameters of the components of the systems and reliably estimate their present evolutionary status. Conclusions: AL Cam and V338 Her are confirmed as classical Algols of relatively low mass in similar configurations. Unlike AL Cam, however, V338 Her is still transferring matter between its components, raising interest in the determinability of the evolutionary histories of Algols. AD And is found to be a detached system in which both close stars are of age ~109 yr and is probably a "non-classical" young triple, at an interesting stage of its dynamical evolution. The spectra and reduced photometric data are available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/539/A129

  4. First principle study of magnetic and electronic properties of single X (X = Al, Si) atom added to small carbon clusters (C n X, n = 2-10)

    NASA Astrophysics Data System (ADS)

    Afshar, M.; Hoseini, S. S.; Sargolzaei, M.

    2016-07-01

    In this paper, the magnetic and electronic properties of single aluminum and silicon atom added to small carbon clusters (C n X; X = Al, Si; n = 2-10) are studied in the framework of generalized-gradient approximation using density functional theory. The calculations were performed for linear, two dimensional and three dimensional clusters based on full-potential local-orbital (FPLO) method. The total energies, HOMO-LUMO energy gap and total magnetic moments of the most stable structures are presented in this work. The calculations show that C n Si clusters have more stability compared to C n Al clusters. In addition, our magnetic calculations were shown that the C n Al isomers are magnetic objects whereas C n Si clusters are nonmagnetic objects.

  5. Evaluation of Interfacial Interactions Between Ti-6Al-4V and Mold Use Ti-Added Backup Coat in Investment Casting

    NASA Astrophysics Data System (ADS)

    Cheng, Xu; Chai, Lianjing; Wu, Guoqing; Wang, Hong; Nan, Hai

    2016-05-01

    In this article, the chemical inertness of shell using Ti-added mullite backup coat against molten Ti-6Al-4V (Ti64) alloy was investigated. The metal/shell interfacial microstructures and compositions were characterized using an optical microscope, scanning electron microscope, roughness tester, and X-ray diffractometer; the hardened layer thickness was evaluated using a microhardness tester. By adding titanium powder into the mullite backup coat, the alpha case and hardened layer thickness of the Ti64 castings were largely reduced with good surface finishing. Silicon ions, from the backup coat, penetrated into the alloy and coarsened the β lath at the metal/shell interfacial area. The Ti powder in the mullite backup coat oxidized and interacted with silica during mold firing and casting, which reduced the silicon and oxygen concentrations at the metal/shell interfacial area. The oxygen penetration depth is thicker than the alpha case layer thickness, and around 0.26 wt pct, oxygen can obviously coarsen the alpha lath at the metal/shell interfacial area during investment casting.

  6. Ascorbate, added after irradiation, reduces the mutant yield and alters the spectrum of CD59- mutations in A(L) cells irradiated with high LET carbon ions

    NASA Technical Reports Server (NTRS)

    Ueno, Akiko; Vannais, Diane; Lenarczyk, Marek; Waldren, Charles A.; Chatterjee, A. (Principal Investigator)

    2002-01-01

    It has been reported that X-ray induced HPRT- mutation in cultured human cells is prevented by ascorbate added after irradiation. Mutation extinction is attributed to neutralization by ascorbate, of radiation-induced long-lived radicals (LLR) with half-lives of several hours. We here show that post-irradiation treatment with ascorbate (5 mM added 30 min after radiation) reduces, but does not eliminate, the induction of CD59- mutants in human-hamster hybrid A(L) cells exposed to high-LET carbon ions (LET of 100 KeV/microm). RibCys, [2(R,S)-D-ribo-1',2',3',4'-Tetrahydroxybutyl]-thiazolidene-4(R)-ca riboxylic acid] (4 mM) gave a similar but lesser effect. The lethality of the carbon ions was not altered by these chemicals. Preliminary data are presented that ascorbate also alters the spectrum of CD59- mutations induced by the carbon beam, mainly by reducing the incidence of small mutations and mutants displaying transmissible genomic instability (TGI), while large mutations are unaffected. Our results suggest that LLR are important in initiating TGI.

  7. Influence of Intensive Melt Shearing on the Microstructure and Mechanical Properties of an Al-Mg Alloy with High Added Impurity Content

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Hari Babu, N.; Scamans, G. M.; Fan, Z.

    2011-10-01

    We have investigated the influence of melt conditioning by intensive shearing on the mechanical behavior and microstructure of Al-Mg-Mn-Fe-Cu-Si alloy sheet produced from a small book mold ingot with high added impurity content. The melt conditioned ingot has fine grains throughout its cross section, whereas a conventionally cast ingot, without melt shearing, has coarser grains and shows a wider variation of grain size. Both needle-shaped and coarse Chinese script iron bearing intermetallic particles are found in the microstructure at the center of the conventionally processed ingot, but for the melt conditioned ingot, only fine Chinese script intermetallic particles are observed. In addition to the iron bearing intermetallics, Mg2Si particles are also observed. The ingots were rolled to thin sheet and solution heat treated (SHT). During rolling, the iron-based intermetallics and Mg2Si particles are broken and aligned along the rolling direction. Yield strength (YS), ultimate tensile strength (UTS), and elongation of the intensively melt sheared and processed sheet are all improved compared to the conventionally cast and processed sheet. Fractographic analysis of the tensile fracture surfaces shows that the clustered and coarse iron bearing intermetallic particles are responsible for the observed reduction in mechanical properties of the conventionally cast sheet. We have shown that by refining the initial microstructure of the ingot by intensive shear melt conditioning, it is possible to achieve improved mechanical properties at the final sheet gage of an AlMgMn alloy with a high content of impurities.

  8. Emplacement conditions of the 1256 AD Al-Madinah lava flow field in Harrat Rahat, Kingdom of Saudi Arabia - Insights from surface morphology and lava flow simulations

    NASA Astrophysics Data System (ADS)

    Kereszturi, Gábor; Németh, Károly; Moufti, Mohammed R.; Cappello, Annalisa; Murcia, Hugo; Ganci, Gaetana; Del Negro, Ciro; Procter, Jonathan; Zahran, Hani Mahmoud Ali

    2016-01-01

    Lava flow hazard modelling requires detailed geological mapping, and a good understanding of emplacement settings and the processes involved in the formation of lava flows. Harrat Rahat, Kingdom of Saudi Arabia, is a large volcanic field, comprising about 1000 predominantly small-volume volcanoes most of which have emitted lava flows of various lengths. A few eruptions took place in this area during the Holocene, and they were located in the northern extreme of the Harrat Rahat, a close proximity to critical infrastructure and population living in Al-Madinah City. In the present study, we combined field work, high resolution digital topography and morphometric analysis to infer the emplacement history of the last historical event in the region represented by the 1256 AD Al-Madinah lava flow field. These data were also used to simulate 1256 AD-type lava flows in the Harrat Rahat by the MAGFLOW lava flow emplacement model, which is able to relate the flow evolution to eruption conditions. The 1256 AD lava flow field extent was mapped at a scale of 1:1000 from a high resolution (0.5 m) Light Detection And Ranging (LiDAR) Digital Terrain Model (DTM), aerial photos with field support. The bulk volume of the lava flow field was estimated at 0.4 km3, while the source volume represented by seven scoria cone was estimated at 0.023 km3. The lava flow covered an area of 60 km2 and reached a maximum length of 23.4 km. The lava flow field comprises about 20.9% of pāhoehoe, 73.8% of 'a'ā, and 5.3% of late-stage outbreaks. Our field observation, also suggests that the lava flows of the Harrat Rahat region are mainly core-dominated and that they formed large lava flow fields by amalgamation of many single channels. These channels mitigated downslope by topography-lava flow and channel-channel interactions, highlighting this typical process that needs to be considered in the volcanic hazard assessment in the region. A series of numerical lava flow simulations was carried out

  9. Food branding influences ad libitum intake differently in children depending on weight status. Results of a pilot study.

    PubMed

    Forman, Jamie; Halford, Jason C G; Summe, Heather; MacDougall, Megan; Keller, Kathleen L

    2009-08-01

    Environmental changes have facilitated the rapid increase in childhood obesity. One such change is increased presence of food marketing which promotes intake of high-fat, energy-dense foods. This study tested the hypotheses that overweight (OW) children are more sensitive to the intake-enhancing effects of food branding than non-OW children, and that the relationship between weight status and intake of branded foods is mediated by level of food brand awareness. Forty-three non-OW (n = 23) and OW (n = 20) children from diverse ethnic backgrounds participated in four dinnertime visits to test their intake of meals where food brands were present ("branded") or absent ("unbranded"). Food brand awareness was assessed by testing children's abilities to match food brand logos with correct foods and name specific brands from recall. Weight and height were measured on the first visit to determine BMI z-score and weight status. OW children consumed significantly more energy per meal than non-OW. Child age and brand awareness were positively associated. OW children consumed an additional 40 kcal in branded vs. unbranded meals whereas non-OW children consumed 45 kcal less in branded meals. Overweight children showed greater responsiveness to food branding, and they may be at risk in environments that are highly inundated with messages about food.

  10. Demonstration of tank effect on growth indices of juvenile rainbow trout (Oncorhynchus mykiss) during an ad libitum feeding trial.

    PubMed

    Speare, D J; MacNair, N; Hammell, K L

    1995-10-01

    Growth indices were examined in 24 identically managed tanks, each containing 120 diploid juvenile rainbow trout (initial mean body weight, 9.3 g) during a 12-week study to examine tank effects associated with tank location in a multi user research facility. Growth indices included mean body weight, feed intake, feed conversion index, and specific growth rate. The null hypothesis that tank effect had no effect on growth over the 12-week period was rejected (P = 0.038), and mean weight in individual tanks differed by as much as 18.7%). During the study it was determined that the proximity of tanks to common-use walkways in the facility could affect growth indices. This was indicated by significant differences in the mean fish weights among blocks of tanks served by different header tanks after 4 (P = 0.001) and 8 (P = 0.024) week. The block containing tanks of fish with the highest them weight was nearest to the 2 common-use walkways in the facility. Fish in this block of tanks, compared with those in other blocks, had significantly greater feed intake but no significant differences in conversion efficiency. Compensatory growth, a well known growth attribute in fishes, diminished the difference in mean weight be tween these blocks of tanks by the end of the study. Comparison of paired ranks within header tank blocks indicated that fish in those located nearest to walkways had higher feeding rates over the 12-week period (P = 0.048), but less efficient feed conversion (P = 0.040) than did fish in matched tanks located farthest from walkways. However, there were no differences in mean weight of fish. Results of this trial document the risks involved in identifying fish in a tank as the experimental unit when treatments are administered to the tank of fish, the latter being the true experimental unit.

  11. Chocolate versions of the Food Cravings Questionnaires. Associations with chocolate exposure-induced salivary flow and ad libitum chocolate consumption.

    PubMed

    Meule, Adrian; Hormes, Julia M

    2015-08-01

    The Food Cravings Questionnaires are the most commonly used instruments for the assessment of trait and state food craving. Chocolate is the most frequently craved food in Western societies. In the current studies, the Food Cravings Questionnaire-Trait-reduced (FCQ-T-r) and the Food Cravings Questionnaire-State (FCQ-S) were adapted to capture strong urges for chocolate. In study 1, students (n = 492; 81.3% female) completed chocolate versions of the FCQ-T-r and FCQ-S among other measures online. The FCQ-T-r (α = .94) comprised two subscales representing lack of control (α = .91) and thoughts about chocolate (α = .91). The FCQ-S (α = .87) comprised two subscales representing chocolate craving (α = .90) and hunger (α = .85). FCQ-T-r scores were significantly and positively correlated with self-reported frequency of consuming chocolate and with scores on the Attitudes to Chocolate Questionnaire, indicating good convergent validity. In study 2, students (n = 76; 73.7% female) underwent a chocolate exposure in the laboratory. FCQ-S scores increased during chocolate exposure and increases in momentary chocolate craving were significantly positively correlated with increases in salivary flow. Higher momentary chocolate craving was positively correlated with higher laboratory chocolate consumption. Exploratory analyses revealed that increases in salivary flow were only associated with increased chocolate consumption in participants scoring high, but not low on trait chocolate craving. The chocolate versions of the FCQ-T-r and FCQ-S represent reliable and valid self-report measures for the assessment of trait and state chocolate craving.

  12. Food branding influences ad libitum intake differently in children depending on weight status. Results of a pilot study.

    PubMed

    Forman, Jamie; Halford, Jason C G; Summe, Heather; MacDougall, Megan; Keller, Kathleen L

    2009-08-01

    Environmental changes have facilitated the rapid increase in childhood obesity. One such change is increased presence of food marketing which promotes intake of high-fat, energy-dense foods. This study tested the hypotheses that overweight (OW) children are more sensitive to the intake-enhancing effects of food branding than non-OW children, and that the relationship between weight status and intake of branded foods is mediated by level of food brand awareness. Forty-three non-OW (n = 23) and OW (n = 20) children from diverse ethnic backgrounds participated in four dinnertime visits to test their intake of meals where food brands were present ("branded") or absent ("unbranded"). Food brand awareness was assessed by testing children's abilities to match food brand logos with correct foods and name specific brands from recall. Weight and height were measured on the first visit to determine BMI z-score and weight status. OW children consumed significantly more energy per meal than non-OW. Child age and brand awareness were positively associated. OW children consumed an additional 40 kcal in branded vs. unbranded meals whereas non-OW children consumed 45 kcal less in branded meals. Overweight children showed greater responsiveness to food branding, and they may be at risk in environments that are highly inundated with messages about food. PMID:19481125

  13. Contributions of Ibn Al-Nafis (1210-1288 AD) to the progress of medicine and urology. A study and translations from his medical works.

    PubMed

    Abdel-Halim, Rabie E

    2008-01-01

    This primary-source study of 4 medical works of the 13th century Muslim scholar Ibn Al-Nafis confirmed that his Kitab Al-Mujaz Fi Al-Tibb was authored as an independent book meant to be a handbook for medical students and practitioners not as an epitome of Kitab Al-Qanun of Ibn Sina as thought by recent historians. His huge medical encyclopedia, Al-Shamil, represents a wave of intense scientific activity that spread among the scholars of Cairo and Damascus following the massive destruction of books by Hulako's Army during the devastation of Baghdad in 1258. Like his predecessors in the Islamic Era, Ibn Al-Nafis critically appraised the views of scholars before him in the light of his own experimentation and direct observations. Accordingly, in his books Sharh Tashreeh Al-Qanun, Risalat al-Aadaa and Al-Risalah Al-Kameleyyah, we find the first description of the coronary vessels and the true concept of the blood supply of the heart as well as the correct description of the pulmonary circulation and the beginnings of the proper understanding of the systemic circulation. Those discoveries of Ibn Al-Nafis, translated to Latin by Andreas Alpagus printed in Venice in 1547, appeared, 6 years later, in the Christianismi Restituto of Servetus and, in 1555, in the De Fabrica Humani Corporis of Vesalius 2nd edition then in the works of Valvarde 1554, Columbus 1559, Cesalpino 1571, and finally Harvey in 1628. Furthermore, this study documented several other contributions of Ibn Al-Nafis to the progress of human functional anatomy and to advances in medical and surgical practice. PMID:18176669

  14. 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.

  15. Value Added?

    ERIC Educational Resources Information Center

    UCLA IDEA, 2012

    2012-01-01

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

  16. Effects of Ca and H2O2 added to RPMI on the fretting corrosion of Ti6Al4V.

    PubMed

    Montague, A; Merritt, K; Brown, S; Payer, J

    1996-12-01

    Titanium and its alloys have demonstrated considerable success in various surgical procedures including orthopedic, dental, and cardiovascular surgery. However, particulate debris from corrosion and wear is present in a considerable quantity in tissue local to the implant. This study evaluated the effect of Ca, since it is present in both serum and bone, and H2O2, since it is produced through local inflammation, on the amount of titanium release. Four sets of Ti6Al4V plates and Ti6Al4V screws were used. Each set was designated to one of four solutions: RPMI (cell culture growth media), RPMI with CaCl2, RPMI with CaCO3, and RPMI with H2O2. A fretter was used to cause corrosion by creating micromotion between two screws and a two-hole plate of Ti6Al4V. After fretting for 72 h, weight loss of the plate and screws and the amount of Ti and vanadium (V) in solution was used to assess the amount of fretting corrosion which had occurred. Results of weight loss and Ti in solution indicated that the presence of H2O2 increased the amount of particulate debris produced in RPMI as compared with RPMI alone. The addition of CaCl2 to RPMI also increased both weight loss and Ti in solution compared with RPMI alone. The addition of CaCO2, however, did not give values significantly different from RPMI alone. Comparison of weight loss and Ti in solution indicated that the increase in fretting corrosion was not different between RPMI with CaCl2 and RPMI with H2O2. The particulate wear debris from the four solutions was black in color and the size of the particulate produced was compared using a Coulter Multisizer. The results indicated that particles produced in the four solutions were not different, with mean values between 1.324 and 1.100 microns, and they were similar in size to the particulate found in tissues surrounding failed total hip replacements. In order to better understand the role of Ca in the fretting corrosion of Ti6Al4V, energy dispersive x-ray analysis (EDXA) using

  17. Evaluación de la utilidad diagnóstica de la versión española del cuestionario al informador «AD8»☆

    PubMed Central

    Pardo, C. Carnero; de la Vega Cotarelo, R.; Alcalde, S. López; Aparicio, C. Martos; Carrillo, R. Vílchez; Gavilán, E. Mora; Galvin, J.E.

    2012-01-01

    Introducción El AD8 es un cuestionario al informador breve que puede ser autoaplicado y facilita la identificación de deterioro cognitivo (DC); nuestro objetivo es evaluar la utilidad diagnóstica (UD) de una versión española. Material y métodos Estudio transversal en una muestra clínica de díadas paciente/ informador, 330 sujetos con sospecha de DC o demencia (DEM) y 71 controles. Se ha evaluado la consistencia interna (α de Cronbach) y la validez (correlaciones parciales con estadio GDS, Fototest e índice funcional [IF]). La UD se ha evaluado para no DC vs DC (GDS 3–4) por medio del área bajo la curva ROC (aROC) y se ha considerado mejor punto de corte aquel que hacía máximo el índice de Youden. Resultados En la muestra, 105 no tenían DC, 99 tenían DC sin DEM y 203 DEM. La consistencia interna es alta (α 0,90, IC del 95%, 0,89–0,92), al igual que las correlaciones con GDS (r = 0,72, p < 0,001), Fototest (r = −0,61, p < 0,001) e IF (r = 0,59, p < 0,001). El aROC del AD8 es 0,90 (IC del 95%, 0,86–0,93), sin diferencia significativa con la del Fototest (aROC 0,93, IC del 95%, 0,89–0,96); el mejor punto de corte es 3/4 con sensibilidad de 0,93 (IC del 95%, 0,88–0,96), especificidad de 0,81 (IC del 95%, 0,72–0,88) y el 88,8% de las clasificaciones correctas. El uso conjunto de AD8 y Fototest mejora de forma significativa la UD de ambos (aROC 0,96, IC del 95%, 0,93–0,98, p < 0,05). Conclusiones La versión española del AD8 conserva las cualidades psicométricas y la UD de la versión original; su uso combinado con el Fototest mejora de forma significativa la UD de ambos. PMID:22652137

  18. DIS in AdS

    SciTech Connect

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

    2009-03-23

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

  19. Conductance control at the LaAlO{sub 3}/SrTiO{sub 3}-interface by a multiferroic BiFeO{sub 3} ad-layer

    SciTech Connect

    Mix, Christian; Finizio, Simone; Kläui, Mathias; Jakob, Gerhard

    2014-06-30

    Multilayered BiFeO{sub 3} (BFO)/LaAlO{sub 3} (LAO) thin film samples were fabricated on SrTiO{sub 3} (STO) substrates by pulsed laser deposition. In this work, the ferroelectric polarization of a multiferroic BFO ad-layer on top of the quasi-two-dimensional electron gas (2DEG) at the LAO/STO interface is used to manipulate the conductivity of the quasi-2DEG. By microstructuring the conductive area of the LAO/STO-interface, a four-point geometry for the measurement of the resistivity was achieved. Piezo force microscopy allows for imaging and poling the spontaneous ferroelectric polarization of the multiferroic layer. The resistance changes showed a linear dependence on the area scanned and a hysteretic behavior with respect to the voltages applied in the scanning process. This is evidence for the ferroelectric polarization of the multiferroic causing the resistance changes. Coupling the antiferromagnetic BFO layer to another ferromagnetic layer could enable a magnetic field control of the conductance of the quasi-2DEG at the LAO/STO interface.

  20. Cardiovascular, Metabolic Effects and Dietary Composition of Ad-Libitum Paleolithic vs. Australian Guide to Healthy Eating Diets: A 4-Week Randomised Trial.

    PubMed

    Genoni, Angela; Lyons-Wall, Philippa; Lo, Johnny; Devine, Amanda

    2016-01-01

    (1) BACKGROUND: The Paleolithic diet is popular in Australia, however, limited literature surrounds the dietary pattern. Our primary aim was to compare the Paleolithic diet with the Australian Guide to Healthy Eating (AGHE) in terms of anthropometric, metabolic and cardiovascular risk factors, with a secondary aim to examine the macro and micronutrient composition of both dietary patterns; (2) METHODS: 39 healthy women (mean ± SD age 47 ± 13 years, BMI 27 ± 4 kg/m²) were randomised to either the Paleolithic (n = 22) or AGHE diet (n = 17) for four weeks. Three-day weighed food records, body composition and biochemistry data were collected pre and post intervention; (3) RESULTS: Significantly greater weight loss occurred in the Paleolithic group (-1.99 kg, 95% CI -2.9, -1.0), p < 0.001). There were no differences in cardiovascular and metabolic markers between groups. The Paleolithic group had lower intakes of carbohydrate (-14.63% of energy (E), 95% CI -19.5, -9.7), sodium (-1055 mg/day, 95% CI -1593, -518), calcium (-292 mg/day 95% CI -486.0, -99.0) and iodine (-47.9 μg/day, 95% CI -79.2, -16.5) and higher intakes of fat (9.39% of E, 95% CI 3.7, 15.1) and β-carotene (6777 μg/day 95% CI 2144, 11410) (all p < 0.01); (4) CONCLUSIONS: The Paleolithic diet induced greater changes in body composition over the short-term intervention, however, larger studies are recommended to assess the impact of the Paleolithic vs. AGHE diets on metabolic and cardiovascular risk factors in healthy populations. PMID:27223304

  1. The clinical effect of dentifrices containing stabilized stannous fluoride on plaque formation and gingivitis--a six-month study with ad libitum brushing.

    PubMed

    Beiswanger, B B; Doyle, P M; Jackson, R D; Mallatt, M E; Mau, M s; Bollmer, B W; Crisanti, M M; Guay, C B; Lanzalaco, A C; Lukacovic, M F

    1995-01-01

    The effects of stabilized 0.454% stannous fluoride dentifrices on supragingival plaque, gingival inflammation and gingival bleeding were studied in 549 adult male and female subjects who completed a six-month, double blind clinical study. Following an oral prophylaxis, subjects were randomly assigned to brush with one of the following dentifrices: 1) 0.454% SnF2 stabilized with 2.08% sodium gluconate, 2) 0.454% SnF2 stabilized with 4.16% sodium gluconate, 3) an experimental dentifrice, or 4) 0.243% NaF control dentifrice. Follow-up examinations were conducted at 3 and 6 months. Compared to the control dentifrice at 6 months, stannous fluoride dentifrices stabilized with 2.08% or 4.16% sodium gluconate significantly reduced gingivitis by 18.8% and 18.0%, respectively. There were no statistically significant differences between the two stabilized SnF2 groups with respect to their beneficial effects on gingival health. Gingival bleeding was also reduced, relative to the control dentifrice, for both stabilized SnF2 dentifrices. However, these differences were not statistically significant at p=0.05. The stabilized SnF2 dentifrices were not significantly different from the control dentifrice in their effects on supragingival plaque. No significant differences in adverse oral soft tissue effects were observed between the test and control groups. As expected, accumulation of extrinsic tooth stain increased in the stabilized SnF2 groups. However, the difficulty in removing accumulated dental stain was similar between the control and stabilized SnF2 dentifrices. Since use of SnF2 dentifrices has been reported to produce tooth stain, gingivitis examinations were done with and without custom-made tooth covers to evaluate the potential for examiner bias. Comparable gingivitis and gingival bleeding benefits were observed when the evaluations were conducted with or without the tooth covers. Results from this study support that 0.454% stabilized stannous fluoride dentifrices can provide an important adjunct to the prevention and control of gingivitis when used in combination with regular personal oral hygiene procedures and professional care.

  2. Dietary protein level and source differentially affect bone metabolism, strength, and intestinal calcium transporter expression during ad libitum and food-restricted conditions in male rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High protein diets may attenuate bone loss during energy restriction (ER). The objective of the current study was to determine whether high protein diets suppress bone turnover and improve bone quality in rats during ER and whether dietary protein source affects this relationship. Eighty 12-week o...

  3. Cardiovascular, Metabolic Effects and Dietary Composition of Ad-Libitum Paleolithic vs. Australian Guide to Healthy Eating Diets: A 4-Week Randomised Trial

    PubMed Central

    Genoni, Angela; Lyons-Wall, Philippa; Lo, Johnny; Devine, Amanda

    2016-01-01

    (1) Background: The Paleolithic diet is popular in Australia, however, limited literature surrounds the dietary pattern. Our primary aim was to compare the Paleolithic diet with the Australian Guide to Healthy Eating (AGHE) in terms of anthropometric, metabolic and cardiovascular risk factors, with a secondary aim to examine the macro and micronutrient composition of both dietary patterns; (2) Methods: 39 healthy women (mean ± SD age 47 ± 13 years, BMI 27 ± 4 kg/m2) were randomised to either the Paleolithic (n = 22) or AGHE diet (n = 17) for four weeks. Three-day weighed food records, body composition and biochemistry data were collected pre and post intervention; (3) Results: Significantly greater weight loss occurred in the Paleolithic group (−1.99 kg, 95% CI −2.9, −1.0), p < 0.001). There were no differences in cardiovascular and metabolic markers between groups. The Paleolithic group had lower intakes of carbohydrate (−14.63% of energy (E), 95% CI −19.5, −9.7), sodium (−1055 mg/day, 95% CI −1593, −518), calcium (−292 mg/day 95% CI −486.0, −99.0) and iodine (−47.9 μg/day, 95% CI −79.2, −16.5) and higher intakes of fat (9.39% of E, 95% CI 3.7, 15.1) and β-carotene (6777 μg/day 95% CI 2144, 11410) (all p < 0.01); (4) Conclusions: The Paleolithic diet induced greater changes in body composition over the short-term intervention, however, larger studies are recommended to assess the impact of the Paleolithic vs. AGHE diets on metabolic and cardiovascular risk factors in healthy populations. PMID:27223304

  4. 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.

  5. Drinking guidelines for exercise: what evidence is there that athletes should drink "as much as tolerable", "to replace the weight lost during exercise" or "ad libitum"?

    PubMed

    Noakes, T D

    2007-05-01

    The most recent (1996) drinking guidelines of the American College of Sports Medicine (ACSM) propose that athletes should drink "as much as tolerable" during exercise. Since some individuals can tolerate rates of free water ingestion that exceed their rates of free water loss during exercise, this advice has caused some to overdrink leading to water retention, weight gain and, in a few, death from exercise-associated hyponatraemic encephalopathy. The new drinking guidelines of the International Olympic Committee (IOC), recently re-published in this Journal, continue to argue that athletes must drink enough to replace all their weight lost during exercise and to ingest sodium chloride since sodium is "the electrolyte most critical to performance and health". In this rebuttal to that Consensus Document, I argue that these new guidelines, like their predecessors, lack an adequate, scientifically proven evidence base. Nor have they been properly evaluated in appropriately controlled, randomized, prospective clinical trials. In particular, these new guidelines provide erroneous recommendations on five topics. If novel universal guidelines for fluid ingestion during exercise are to be promulgated by important international bodies including the IOC, they should first be properly evaluated in appropriately controlled, randomized, prospective clinical trials conducted under environmental and other conditions that match those found in "out-of-doors" exercise. This, and the potential influence of commercial interests on scientific independence and objectivity, are the two most important lessons to be learned from the premature adoption of those 1996 ACSM drinking guidelines that are not evidence-based. These concerns need to be addressed before the novel IOC guidelines are accepted uncritically. Otherwise the predictable consequences of the premature adoption of the 1996 ACSM guidelines will be repeated.

  6. 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.

  7. Polarised black holes in AdS

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  8. 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.

  9. Agricultural Education: Value Adding.

    ERIC Educational Resources Information Center

    Riesenberg, Lou E.; And Others

    1989-01-01

    This issue develops the theme of "Agricultural Education--Value Adding." The concept value adding has been a staple in the world of agricultural business for describing adding value to a commodity that would profit the producer and the local community. Agricultural education should add value to individuals and society to justify agricultural…

  10. The forecaster's added value

    NASA Astrophysics Data System (ADS)

    Turco, M.; Milelli, M.

    2009-09-01

    To the authors' knowledge there are relatively few studies that try to answer this topic: "Are humans able to add value to computer-generated forecasts and warnings ?". Moreover, the answers are not always positive. In particular some postprocessing method is competitive or superior to human forecast (see for instance Baars et al., 2005, Charba et al., 2002, Doswell C., 2003, Roebber et al., 1996, Sanders F., 1986). Within the alert system of ARPA Piemonte it is possible to study in an objective manner if the human forecaster is able to add value with respect to computer-generated forecasts. Every day the meteorology group of the Centro Funzionale of Regione Piemonte produces the HQPF (Human QPF) in terms of an areal average for each of the 13 regional warning areas, which have been created according to meteo-hydrological criteria. This allows the decision makers to produce an evaluation of the expected effects by comparing these HQPFs with predefined rainfall thresholds. Another important ingredient in this study is the very dense non-GTS network of rain gauges available that makes possible a high resolution verification. In this context the most useful verification approach is the measure of the QPF and HQPF skills by first converting precipitation expressed as continuous amounts into ‘‘exceedance'' categories (yes-no statements indicating whether precipitation equals or exceeds selected thresholds) and then computing the performances for each threshold. In particular in this work we compare the performances of the latest three years of QPF derived from two meteorological models COSMO-I7 (the Italian version of the COSMO Model, a mesoscale model developed in the framework of the COSMO Consortium) and IFS (the ECMWF global model) with the HQPF. In this analysis it is possible to introduce the hypothesis test developed by Hamill (1999), in which a confidence interval is calculated with the bootstrap method in order to establish the real difference between the

  11. Effect of calcium lactate in erosion and S. mutans in rats when added to Coca-Cola.

    PubMed

    Beiraghi, S; Atkins, S; Rosen, S; Wilson, S; Odom, J; Beck, M

    1989-12-01

    Thirty-six Sprague Dawley rats, 22 days of age, were divided randomly into three groups of 12 each and housed in a programmable feeder. The three experimental groups received either Coca-Cola (CC), Coca-Cola with calcium lactate (CC-CaL), or distilled water. The programmable feeder was set to deliver 17 equal volumes of fluid per day with each feeding period lasting between 80-90 min. All groups were given Diet MIT 305 in one premeasured amount per 24 hr period (ad libitum). The pH of the CC with calcium lactate was adjusted to match the CC without calcium lactate by the addition of citric and phosphoric acids. The test period lasted five weeks. Each week, the food and fluid consumed and the weight gain were measured. Erosion of the teeth was scored by the method of Restarski et al. (1945). ANOVA indicated that there was a significant difference in the amount of erosion among groups. A Newman-Keuls analysis showed that the mean erosion score of the CC group was significantly greater (P less than 0.05) than that of the CC-CaL and distilled water groups (54.2 +/- 0.12; 0.0275 +/- 0.0123; 0.132 +/- 0.070, respectively). There was no significant difference in erosion between the CC-CaL and distilled water groups. There was no difference in the amount of food and fluid consumed among the group of rats. In conclusion, calcium lactate added to CC resulted in significantly reduced tooth erosion in rats.

  12. Adding flavor to AdS4/CFT3

    NASA Astrophysics Data System (ADS)

    Ammon, Martin; Erdmenger, Johanna; Meyer, René; O'Bannon, Andy; Wrase, Timm

    2009-11-01

    Aharony, Bergman, Jafferis, and Maldacena have proposed that the low-energy description of multiple M2-branes at a Bbb C4/Bbb Zk singularity is a (2+1)-dimensional Script N = 6 supersymmetric U(Nc) × U(Nc) Chern-Simons matter theory, the ABJM theory. In the large-Nc limit, its holographic dual is supergravity in AdS4 × S7/Bbb Zk. We study various ways to add fields that transform in the fundamental representation of the gauge groups, i.e. flavor fields, to the ABJM theory. We work in a probe limit and perform analyses in both the supergravity and field theory descriptions. In the supergravity description we find a large class of supersymmetric embeddings of probe flavor branes. In the field theory description, we present a general method to determine the couplings of the flavor fields to the fields of the ABJM theory. We then study four examples in detail: codimension-zero Script N = 3 supersymmetric flavor, described in supergravity by Kaluza-Klein monopoles or D6-branes; codimension-one Script N = (0,6) supersymmetric chiral flavor, described by D8-branes; codimension-one Script N = (3,3) supersymmetric non-chiral flavor, described by M5/D4-branes; codimension-two Script N = 4 supersymmetric flavor, described by M2/D2-branes. Finally we discuss special physical equivalences between brane embeddings in M-theory, and their interpretation in the field theory description.

  13. Twistor methods for AdS5

    NASA Astrophysics Data System (ADS)

    Adamo, Tim; Skinner, David; Williams, Jack

    2016-08-01

    We consider the application of twistor theory to five-dimensional anti-de Sitter space. The twistor space of AdS5 is the same as the ambitwistor space of the four-dimensional conformal boundary; the geometry of this correspondence is reviewed for both the bulk and boundary. A Penrose transform allows us to describe free bulk fields, with or without mass, in terms of data on twistor space. Explicit representatives for the bulk-to-boundary propagators of scalars and spinors are constructed, along with twistor action functionals for the free theories. Evaluating these twistor actions on bulk-to-boundary propagators is shown to produce the correct two-point functions.

  14. 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.

  15. Shadows, currents, and AdS fields

    SciTech Connect

    Metsaev, R. R.

    2008-11-15

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

  16. 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.

  17. The antagonistic effects of L-dopa and eserine on Al-induced neurobehavioral deficits in rats.

    PubMed

    Zheng, Y X; Liang, Y X

    1998-12-01

    The main goals of the study were to elucidate the mechanism of Al-induced behavioral toxicity and to explore the possible link between the changes in the metabolism of monoaminergic or cholinergic transmitters and neurobehavioral effects. Three groups (12 rats in each group) were fed with aluminum chloride in drinking water (1600 mg/l) ad libitum through a 90-day exposure period. The controls were fed with distilled water. From the 60th to 90th day of treatment, two of the three Al-treated groups were administered with L-dopa (220 mg/kg.bw) and eserine (0.4 mg/kg.bw) by gavage, respectively. A two-item neurobehavioral test battery consisting of step down test and Morris water maze task was used for rats after three months treatment. In the step-down test, markedly shortened the step-down latency (SDL) and the number of step-down (NSD) were observed in the Al-treated group (P < 0.05, vs. control). On the contrary, only slight changes were found in the rats treated with aluminum combined with L-dopa or eserine (P > 0.05, vs control). In eserine and L-dopa antagonized groups, the mean escape latencies of Morris water maze approached a level close to that of the controls (P > 0.05). The results showed that the Al-induced memory and learning impairment could be reduced by L-dopa or eserine. It is suggested that the depletion of dopaminergic and cholinergic transmitters in the central nervous system might play an important role in Al-induced neurotoxicity.

  18. 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…

  19. Introducing ADS Labs

    NASA Astrophysics Data System (ADS)

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

    2011-05-01

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

  20. Two Virasoro symmetries in stringy warped AdS3

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  1. ALS Association

    MedlinePlus

    ... toward a world without ALS! Walk to Defeat ALS® Walk to Defeat ALS® draws people of all ... We need your help. I Will Advocate National ALS Registry The National ALS Registry is a congressionally ...

  2. Leading Change, Adding Value.

    PubMed

    Evans, Nick

    2016-09-12

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

  3. Nonlinear realization of local symmetries of AdS space

    SciTech Connect

    Clark, T.E.; Love, S.T.; Nitta, Muneto; Veldhuis, T. ter

    2005-10-15

    Coset methods are used to construct the action describing the dynamics associated with the spontaneous breaking of the local symmetries of AdS{sub d+1} space due to the embedding of an AdS{sub d} brane. The resulting action is an SO(2,d) invariant AdS form of the Einstein-Hilbert action, which in addition to the AdS{sub d} gravitational vielbein, also includes a massive vector field localized on the brane. Its long wavelength dynamics is the same as a massive Abelian vector field coupled to gravity in AdS{sub d} space.

  4. Dressing phases of AdS3/CFT2

    NASA Astrophysics Data System (ADS)

    Borsato, Riccardo; Ohlsson Sax, Olof; Sfondrini, Alessandro; Stefański, Bogdan, Jr.; Torrielli, Alessandro

    2013-09-01

    We determine the all-loop dressing phases of the AdS3/CFT2 integrable system related to type IIB string theory on AdS3×S3×T4 by solving the recently found crossing relations and studying their singularity structure. The two resulting phases present a novel structure with respect to the ones appearing in AdS5/CFT4 and AdS4/CFT3. In the strongly coupled regime, their leading order reduces to the universal Arutyunov-Frolov-Staudacher phase as expected. We also compute their subleading order and compare it with recent one-loop perturbative results and comment on their weak-coupling expansion.

  5. Bubbling geometries for AdS2× S2

    NASA Astrophysics Data System (ADS)

    Lunin, Oleg

    2015-10-01

    We construct BPS geometries describing normalizable excitations of AdS2×S2. All regular horizon-free solutions are parameterized by two harmonic functions in R 3 with sources along closed curves. This local structure is reminiscent of the "bubbling solutions" for the other AdS p ×S q cases, however, due to peculiar asymptotic properties of AdS2, one copy of R 3 does not cover the entire space, and we discuss the procedure for analytic continuation, which leads to a nontrivial topological structure of the new geometries. We also study supersymmetric brane probes on the new geometries, which represent the AdS2×S2 counterparts of the giant gravitons.

  6. [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, a student…

  7. 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.

  8. Use of a portable, automated, open-circuit gas quantification system and the sulfur hexafluoride tracer technique for measuring enteric methane emissions in Holstein cows fed ad libitum or restricted

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sulfur hexafluoride tracer technique (SF**6) is a commonly used method for measuring CH**4 enteric emissions in ruminants. Studies using SF**6 have shown large variation in CH**4 emissions data, inconsistencies in CH**4 emissions across studies, and potential methodological errors. Therefore, th...

  9. ALS - resources

    MedlinePlus

    Resources - ALS ... The following organizations are good resources for information on amyotrophic lateral sclerosis : Muscular Dystrophy Association -- mda.org/disease/amyotrophic-lateral-sclerosis National Amyotrophic Lateral Sclerosis (ALS) Registry -- ...

  10. Superstring theory in AdS(3) and plane waves

    NASA Astrophysics Data System (ADS)

    Son, John Sang Won

    This thesis is devoted to the study of string theory in AdS 3 and its applications to recent developments in string theory. The difficulties associated with formulating a consistent string theory in AdS3 and its underlying SL(2, R) WZW model are explained. We describe how these difficulties can be overcome by assuming that the SL(2, R) WZW model contains spectral flow symmetry. The existence of spectral flow symmetry in the fully quantum treatment is proved by a calculation of the one-loop string partition function. We consider Euclidean AdS 3 with the time direction periodically identified, and compute the torus partition function in this background. The string spectrum can be reproduced by viewing the one-loop calculation as the free energy of a gas of strings, thus providing a rigorous proof of the results based on spectral flow arguments. Next, we turn to spacetimes that are quotients of AdS 3, which include the BTZ black hole and conical spaces. Strings propagating in the conical space are described by taking an orbifold of strings in AdS3. We show that the twisted states of these orbifolds can be obtained by fractional spectral flow. We show that the shift in the ground state energy usually associated with orbifold twists is absent in this case, and offer a unified framework in which to view spectral flow. Lastly, we consider the RNS superstrings in AdS 3 x S3 x M , where M may be K3 or T 4, based on supersymmetric extensions of SL(2, R) and SU(2) WZW models. We construct the physical states and calculate the spectrum. A subsector of this theory describes strings propagating in the six dimensional plane wave obtained by the Penrose limit of AdS3 x S3 x M . We reproduce the plane wave spectrum by taking J and the radius to infinity. We show that the plane wave spectrum actually coincides with the large J spectrum at fixed radius, i.e. in AdS3 x S3. Relation to some recent topics of interest such as the Frolov-Tseytlin string and strings with critical tension

  11. 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.

  12. Asymptotically AdS spacetimes with a timelike Kasner singularity

    NASA Astrophysics Data System (ADS)

    Ren, Jie

    2016-07-01

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

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

    PubMed

    Jatkar, Dileep P; Sinha, Aninda

    2011-04-29

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

  14. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    NASA Astrophysics Data System (ADS)

    Evnin, Oleg; Jai-akson, Puttarak

    2016-04-01

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

  15. Holography and AdS4 self-gravitating dyons

    NASA Astrophysics Data System (ADS)

    Lugo, A. R.; Moreno, E. F.; Schaposnik, F. A.

    2010-11-01

    We present a self-gravitating dyon solution of the Einstein-Yang-Mills-Higgs equations of motion in asymptotically AdS space. The back reaction of gauge and Higgs fields on the space-time geometry leads to the metric of an asymptotically AdS black hole. Using the gauge/gravity correspondence we analyze relevant properties of the finite temperature quantum field theory defined on the boundary. In particular we identify an order operator, characterize a phase transition of the dual theory on the border and also compute the expectation value of the finite temperature Wilson loop.

  16. AdS box graphs, unitarity and operator product expansions

    NASA Astrophysics Data System (ADS)

    Hoffmann, L.; Mesref, L.; Rühl, W.

    2000-11-01

    We develop a method of singularity analysis for conformal graphs which, in particular, is applicable to the holographic image of AdS supergravity theory. It can be used to determine the critical exponents for any such graph in a given channel. These exponents determine the towers of conformal blocks that are exchanged in this channel. We analyze the scalar AdS box graph and show that it has the same critical exponents as the corresponding CFT box graph. Thus pairs of external fields couple to the same exchanged conformal blocks in both theories. This is looked upon as a general structural argument supporting the Maldacena hypothesis.

  17. Phases of global AdS black holes

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  18. D-branes on AdS flux compactifications

    NASA Astrophysics Data System (ADS)

    Koerber, Paul; Martucci, Luca

    2008-01-01

    We study D-branes in Script N = 1 flux compactifications to AdS4. We derive their supersymmetry conditions and express them in terms of background generalized calibrations. Basically because AdS has a boundary, the analysis of stability is more subtle and qualitatively different from the usual case of Minkowski compactifications. For instance, stable D-branes filling AdS4 may wrap trivial internal cycles. Our analysis gives a geometric realization of the four-dimensional field theory approach of Freedman and collaborators. Furthermore, the one-to-one correspondence between the supersymmetry conditions of the background and the existence of generalized calibrations for D-branes is clarified and extended to any supersymmetric flux background that admits a time-like Killing vector and for which all fields are time-independent with respect to the associated time. As explicit examples, we discuss supersymmetric D-branes on IIA nearly Kähler AdS4 flux compactifications.

  19. Dyonic AdS black holes from magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Caldarelli, Marco M.; Dias, Óscar J. C.; Klemm, Dietmar

    2009-03-01

    We use the AdS/CFT correspondence to argue that large dyonic black holes in anti-de Sitter spacetime are dual to stationary solutions of the equations of relativistic magnetohydrodynamics on the conformal boundary of AdS. The dyonic Kerr-Newman-AdS4 solution corresponds to a charged diamagnetic fluid not subject to any net Lorentz force, due to orthogonal magnetic and electric fields compensating each other. The conserved charges, stress tensor and R-current of the fluid are shown to be in exact agreement with the corresponding quantities of the black hole. Furthermore, we obtain stationary solutions of the Navier-Stokes equations in four dimensions, which yield predictions for (yet to be constructed) charged rotating black strings in AdS5 carrying nonvanishing momentum along the string. Finally, we consider Scherk-Schwarz reduced AdS gravity on a circle. In this theory, large black holes and black strings are dual to lumps of deconfined plasma of the associated CFT. We analyze the effects that a magnetic field introduces in the Rayleigh-Plateau instability of a plasma tube, which is holographically dual to the Gregory-Laflamme instability of a magnetically charged black string.

  20. AdS Branes from Partial Breaking of Superconformal Symmetries

    SciTech Connect

    Ivanov, E.A.

    2005-10-01

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

  1. Worldsheet dilatation operator for the AdS superstring

    NASA Astrophysics Data System (ADS)

    Ramírez, Israel; Vallilo, Brenno Carlini

    2016-05-01

    In this work we propose a systematic way to compute the logarithmic divergences of composite operators in the pure spinor description of the AdS 5 × S 5 superstring. The computations of these divergences can be summarized in terms of a dilatation operator acting on the local operators. We check our results with some important composite operators of the formalism.

  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. Rhazes (865-925 AD), the icon of Persian cardiology.

    PubMed

    Nezhad, Golnoush Sadat Mahmoudi; Dalfardi, Behnam

    2014-12-20

    For many long centuries, the function of the human cardiovascular system was an important issue among scholars of different eras and areas. Abubakr Muhammad ibn Zakariyya al-Razi (865-925 AD), known by the Latin name Rhazes, was one of the scholars concerned with this issue. This physician is recognized as the first great scientist of the Golden Age of Islamic Medicine (9th-12th centuries AD). He authored Kitab al-Mansuri (Liber Al-Mansuri), a ten-volume medical encyclopedia that covers a large number of medical subjects. The first chapter of this book is allocated to human anatomy and functions. In this article, we review the chapter from Al-Mansuri that deals with Rhazes' views on the cardiovascular system. PMID:25465822

  4. Effective Ad-Hoc Committees.

    ERIC Educational Resources Information Center

    Young, David G.

    1983-01-01

    Ad-hoc committees may be symbolic, informational, or action committees. A literature survey indicates such committees' structural components include a suprasystem and three subsystems involving linkages, production, and implementation. Other variables include size, personal factors, and timing. All the factors carry implications about ad-hoc…

  5. 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.

  6. One-loop diagrams in AdS space

    SciTech Connect

    Hung Lingyan; Shang Yanwen

    2011-01-15

    We study the complex scalar loop corrections to the boundary-boundary gauge two-point function in pure AdS space in Poincare coordinates, in the presence of boundary quadratic perturbations to the scalar. These perturbations correspond to double-trace perturbations in the dual CFT and modify the boundary conditions of the bulk scalars in AdS. We find that, in addition to the usual UV divergences, the one-loop calculation suffers from a divergence originating in the limit as the loop vertices approach the AdS horizon. We show that this type of divergence is independent of the boundary coupling; making use of this we extract the finite relative variation of the imaginary part of the loop via Cutkosky rules as the boundary perturbation varies. Applying our methods to compute the effects of a time-dependent impurity to the conductivities using the replica trick in AdS/CFT, we find that generally an IR-relevant disorder reduces the conductivity and that in the extreme low frequency limit the correction due to the impurities overwhelms the planar CFT result even though it is supposedly 1/N{sup 2} suppressed. We also comment on the more physical scenario of a time-independent impurity.

  7. Kolmogorov-Zakharov spectrum in AdS gravitational collapse.

    PubMed

    de Oliveira, H P; Pando Zayas, Leopoldo A; Rodrigues, E L

    2013-08-01

    We study black hole formation during the gravitational collapse of a massless scalar field in asymptotically D-dimensional anti-de Sitter AdS(D) spacetimes for D = 4, 5. We conclude that spherically symmetric gravitational collapse in asymptotically AdS spaces is turbulent and characterized by a Kolmogorov-Zakharov spectrum. Namely, we find that after an initial period of weakly nonlinear evolution, there is a regime where the power spectrum of the Ricci scalar evolves as ω(-s) with the frequency, ω, and s ≈ 1.7 ± 0.1.

  8. Entangled photon-added coherent states

    NASA Astrophysics Data System (ADS)

    Domínguez-Serna, Francisco A.; Mendieta-Jimenez, Francisco J.; Rojas, Fernando

    2016-08-01

    We study the degree of entanglement of arbitrary superpositions of m, n photon-added coherent states (PACS) {|{ψ }rangle } ∝ u {|{{α },m}rangle }{|{{β },n }rangle }+ v {|{{β },n}rangle }{|{{α },m}rangle } using the concurrence and obtain the general conditions for maximal entanglement. We show that photon addition process can be identified as an entanglement enhancer operation for superpositions of coherent states (SCS). Specifically for the known bipartite positive SCS: {|{ψ }rangle } ∝ {|{α }rangle }_a{|{-α }rangle }_b + {|{-α }rangle }_a{|{α }rangle }_b whose entanglement tends to zero for α → 0, can be maximal if al least one photon is added in a subsystem. A full family of maximally entangled PACS is also presented. We also analyzed the decoherence effects in the entangled PACS induced by a simple depolarizing channel . We find that robustness against depolarization is increased by adding photons to the coherent states of the superposition. We obtain the dependence of the critical depolarization p_{ {crit}} for null entanglement as a function of m,n, α and β.

  9. Semiclassical Virasoro blocks from AdS3 gravity

    NASA Astrophysics Data System (ADS)

    Hijano, Eliot; Kraus, Per; Perlmutter, Eric; Snively, River

    2015-12-01

    We present a unified framework for the holographic computation of Virasoro conformal blocks at large central charge. In particular, we provide bulk constructions that correctly reproduce all semiclassical Virasoro blocks that are known explicitly from conformal field theory computations. The results revolve around the use of geodesic Witten diagrams, recently introduced in [1], evaluated in locally AdS3 geometries generated by backreaction of heavy operators. We also provide an alternative computation of the heavy-light semiclassical block — in which two external operators become parametrically heavy — as a certain scattering process involving higher spin gauge fields in AdS3; this approach highlights the chiral nature of Virasoro blocks. These techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.

  10. AdS6 solutions of type II supergravity

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

    Very few AdS6 × M 4 supersymmetric solutions are known: one in massive IIA, and two IIB solutions dual to it. The IIA solution is known to be unique; in this paper, we use the pure spinor approach to give a classification for IIB supergravity. We reduce the problem to two PDEs on a two-dimensional space Σ. M 4 is then a fibration of S 2 over Σ; the metric and fluxes are completely determined in terms of the solution to the PDEs. The results seem likely to accommodate near-horizon limits of ( p, q)-fivebrane webs studied in the literature as a source of CFT5's. We also show that there are no AdS6 solutions in eleven-dimensional supergravity.

  11. Conserved higher-spin charges in AdS4

    NASA Astrophysics Data System (ADS)

    Gelfond, O. A.; Vasiliev, M. A.

    2016-03-01

    Gauge invariant conserved conformal currents built from massless fields of all spins in 4d Minkowski space-time and AdS4 are described in the unfolded dynamics approach. The current cohomology associated with non-zero conserved charges is found. The resulting list of charges is shown to match the space of parameters of the conformal higher-spin symmetry algebra in four dimensions.

  12. On information loss in AdS3/CFT2

    DOE PAGES

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

    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

  13. ADS/CFT and QCD

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.; /Costa Rica U. /SLAC

    2007-02-21

    The AdS/CFT correspondence between string theory in AdS space and conformal .eld theories in physical spacetime leads to an analytic, semi-classical model for strongly-coupled QCD which has scale invariance and dimensional counting at short distances and color confinement at large distances. Although QCD is not conformally invariant, one can nevertheless use the mathematical representation of the conformal group in five-dimensional anti-de Sitter space to construct a first approximation to the theory. The AdS/CFT correspondence also provides insights into the inherently non-perturbative aspects of QCD, such as the orbital and radial spectra of hadrons and the form of hadronic wavefunctions. In particular, we show that there is an exact correspondence between the fifth-dimensional coordinate of AdS space z and a specific impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron in ordinary space-time. This connection allows one to compute the analytic form of the frame-independent light-front wavefunctions, the fundamental entities which encode hadron properties and allow the computation of decay constants, form factors, and other exclusive scattering amplitudes. New relativistic lightfront equations in ordinary space-time are found which reproduce the results obtained using the 5-dimensional theory. The effective light-front equations possess remarkable algebraic structures and integrability properties. Since they are complete and orthonormal, the AdS/CFT model wavefunctions can also be used as a basis for the diagonalization of the full light-front QCD Hamiltonian, thus systematically improving the AdS/CFT approximation.

  14. 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.

  15. 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

  16. Most general AdS3 boundary conditions

    NASA Astrophysics Data System (ADS)

    Grumiller, Daniel; Riegler, Max

    2016-10-01

    We consider the most general asymptotically anti-de Sitter boundary conditions in three-dimensional Einstein gravity with negative cosmological constant. The metric contains in total twelve independent functions, six of which are interpreted as chemical potentials (or non-normalizable fluctuations) and the other half as canonical boundary charges (or normalizable fluctuations). Their presence modifies the usual Fefferman-Graham expansion. The asymptotic symmetry algebra consists of two sl{(2)}_k current algebras, the levels of which are given by k = ℓ/(4 G N ), where ℓ is the AdS radius and G N the three-dimensional Newton constant.

  17. The Chinese comet observation in AD 773 January

    NASA Astrophysics Data System (ADS)

    Chapman, J.; Csikszentmihalyi, M.; Neuhäuser, R.

    2014-11-01

    The strong 14C increase in the year AD 774/5 detected in one German and two Japanese trees was recently suggested to have been caused by an impact of a comet onto Earth and a deposition of large amounts of 14C into the atmosphere (Liu et al. 2014). The authors supported their claim using a report of a historic Chinese observation of a comet ostensibly colliding with Earth's atmosphere in AD 773 January. We show here that the Chinese text presented by those authors is not an original historic text, but that it is comprised of several different sources. Moreover, the translation presented in Liu et al. is misleading and inaccurate. We give the exact Chinese wordings and our English translations. According to the original sources, the Chinese observed a comet in mid January 773, but they report neither a collision nor a large coma, just a long tail. Also, there is no report in any of the source texts about "dust rain in the daytime" as claimed by Liu et al. (2014), but simply a normal dust storm. Ho (1962) reports sightings of this comet in China on AD 773 Jan 15 and/or 17 and in Japan on AD 773 Jan 20 (Ho 1962). At the relevant historic time, the Chinese held that comets were produced within the Earth's atmosphere, so that it would have been impossible for them to report a "collision" of a comet with Earth's atmosphere. The translation and conclusions made by Liu et al. (2014) are not supported by the historical record. Therefore, postulating a sudden increase in 14C in corals off the Chinese coast precisely in mid January 773 (Liu et al. 2014) is not justified given just the 230Th dating for AD 783 ± 14.

  18. 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.

  19. 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.

  20. Influence of coagulation factor x on in vitro and in vivo gene delivery by adenovirus (Ad) 5, Ad35, and chimeric Ad5/Ad35 vectors.

    PubMed

    Greig, Jenny A; Buckley, Suzanne Mk; Waddington, Simon N; Parker, Alan L; Bhella, David; Pink, Rebecca; Rahim, Ahad A; Morita, Takashi; Nicklin, Stuart A; McVey, John H; Baker, Andrew H

    2009-10-01

    The binding of coagulation factor X (FX) to the hexon of adenovirus (Ad) 5 is pivotal for hepatocyte transduction. However, vectors based on Ad35, a subspecies B Ad, are in development for cancer gene therapy, as Ad35 utilizes CD46 (which is upregulated in many cancers) for transduction. We investigated whether interaction of Ad35 with FX influenced vector tropism using Ad5, Ad35, and Ad5/Ad35 chimeras: Ad5/fiber(f)35, Ad5/penton(p)35/f35, and Ad35/f5. Surface plasmon resonance (SPR) revealed that Ad35 and Ad35/f5 bound FX with approximately tenfold lower affinities than Ad5 hexon-containing viruses, and electron cryomicroscopy (cryo-EM) demonstrated a direct Ad35 hexon:FX interaction. The presence of physiological levels of FX significantly inhibited transduction of vectors containing Ad35 fibers (Ad5/f35, Ad5/p35/f35, and Ad35) in CD46-positive cells. Vectors were intravenously administered to CD46 transgenic mice in the presence and absence of FX-binding protein (X-bp), resulting in reduced liver accumulation for all vectors. Moreover, Ad5/f35 and Ad5/p35/f35 efficiently accumulated in the lung, whereas Ad5 demonstrated poor lung targeting. Additionally, X-bp significantly reduced lung genome accumulation for Ad5/f35 and Ad5/p35/f35, whereas Ad35 was significantly enhanced. In summary, vectors based on the full Ad35 serotype will be useful vectors for selective gene transfer via CD46 due to a weaker FX interaction compared to Ad5.

  1. Added Value in Electronic Publications.

    ERIC Educational Resources Information Center

    Bothma, Theo J. D.

    Electronic publications are flooding the market. Some of these publications are created specifically for the electronic environment, but many are conversions of existing material to electronic format. It is not worth the time and effort merely to publish existing material in electronic format if no value is added in the conversion process. The…

  2. Thermodynamics of charged Lovelock: AdS black holes

    NASA Astrophysics Data System (ADS)

    Prasobh, C. B.; Suresh, Jishnu; Kuriakose, V. C.

    2016-04-01

    We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime.

  3. 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.

  4. Superconformal algebras on the boundary of AdS3

    NASA Astrophysics Data System (ADS)

    Rasmussen, Jørgen

    1999-07-01

    Motivated by recent progress on the correspondence between string theory on nti-de Sitter space and conformal field theory, we provide an explicit construction of an infinite dimensional class of superconformal algebras on the boundary of AdS3. These space-time algebras are N extended superconformal algebras of the kind obtainable by hamiltonian reduction of affine SL(2|N/2) current superalgebras for N even, and are induced by the same current superalgebras residing on the world sheet. Thus, such an extended superconformal algebra is generated by N supercurrents and an SL(N/2) current algebra in addition to a U(1) current algebra. The results are obtained within the framework of free field realizations.

  5. Droplet Number Concentration Value Added Product

    2015-08-06

    Cloud droplet number concentration is an important factor in understanding aerosol-cloud interactions. As aerosol concentration increases, it is expected that droplet number concentration (Nd) will increase and droplet size will decrease, for a given liquid water path. This will greatly affect cloud albedo as smaller droplets reflect more shortwave radiation; however, the magnitude and variability of these processes under different environmental conditions is still uncertain.McComiskey et al. (2009) have implemented a method, based onBoers andmore » Mitchell (1994), for calculating Nd from ground-based remote sensing measurements of optical depth and liquid water path. They show that the magnitude of the aerosol-cloud interactions (ACI) varies with a range of factors, including the relative value of the cloud liquid water path (LWP), the aerosol size distribution, and the cloud updraft velocity. Estimates of Nd under a range of cloud types and conditions and at a variety of sites are needed to further quantify the impacts of aerosol cloud interactions. In order to provide data sets for studying aerosol-cloud interactions, the McComiskey et al. (2009) method was implemented as the Droplet Number Concentration (NDROP) value-added product (VAP).« less

  6. Droplet Number Concentration Value Added Product

    SciTech Connect

    Chitra Sivaraman, PNNL

    2015-08-06

    Cloud droplet number concentration is an important factor in understanding aerosol-cloud interactions. As aerosol concentration increases, it is expected that droplet number concentration (Nd) will increase and droplet size will decrease, for a given liquid water path. This will greatly affect cloud albedo as smaller droplets reflect more shortwave radiation; however, the magnitude and variability of these processes under different environmental conditions is still uncertain.McComiskey et al. (2009) have implemented a method, based onBoers and Mitchell (1994), for calculating Nd from ground-based remote sensing measurements of optical depth and liquid water path. They show that the magnitude of the aerosol-cloud interactions (ACI) varies with a range of factors, including the relative value of the cloud liquid water path (LWP), the aerosol size distribution, and the cloud updraft velocity. Estimates of Nd under a range of cloud types and conditions and at a variety of sites are needed to further quantify the impacts of aerosol cloud interactions. In order to provide data sets for studying aerosol-cloud interactions, the McComiskey et al. (2009) method was implemented as the Droplet Number Concentration (NDROP) value-added product (VAP).

  7. 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

  8. 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.

  9. On thermodynamics of charged AdS black holes in extended phases space via M2-branes background

    NASA Astrophysics Data System (ADS)

    Chabab, M.; El Moumni, H.; Masmar, K.

    2016-06-01

    Motivated by a recent work on asymptotically AdS_4 black holes in M-theory, we investigate both thermodynamics and the thermodynamical geometry of Reissner-Nordstrom-AdS black holes from M2-branes. More precisely, we study AdS black holes in AdS4× S7, with the number of M2-branes interpreted as a thermodynamical variable. In this context, we calculate various thermodynamical quantities including the chemical potential, and examine their phase transitions along with the corresponding stability behaviors. In addition, we also evaluate the thermodynamical curvatures of the Weinhold, Ruppeiner, and Quevedo metrics for M2-branes geometry to study the stability of such a black object. We show that the singularities of these scalar curvature's metrics reproduce similar stability results to those obtained by the phase transition diagram via the heat capacities in different ensembles either when the number of the M2 branes or the charge is held fixed. Also, we note that all results derived in Belhaj et al. (Eur Phys J C 76(2):73, 2016) are recovered in the limit of the vanishing charge.

  10. Al Composites

    NASA Astrophysics Data System (ADS)

    Chandanayaka, Tharaka; Azarmi, Fardad

    2014-05-01

    In the present study, cold spraying technique was used to fabricate a metal matrix composite (MMC) that consists of Ni matrix and 20 vol.% Ni3Al particles at two different particle sizes as reinforcement. This study intends to investigate the effect of reinforcement particle size on microstructural and mechanical properties of cold sprayed MMCs. Two different Ni3Al powders with nominal particle size of -45 to +5 and +45 to 100 μm were used as reinforcement in this study. Cold sprayed Ni-Ni3Al samples were subjected to the microstructural observation and characterization prior to any mechanical testing. Then, samples were tested using nano-indentation, Knoop hardness, Vickers hardness, and Resonance frequency to evaluate their mechanical properties. No significant changes were observed in microstructural characteristics due to different particle sizes. The results obtained from a variety of mechanical testings indicated that the increasing reinforcement particle size resulted in the slight reduction of mechanical properties such as elastic modulus and hardness in cold sprayed MMCs. The mechanical interlock between deposited particles defines the bonding strength in cold sprayed samples. Small size particles have a higher velocity and impact resulting in stronger interlock between deformed particles.

  11. ADS's Dexter Data Extraction Applet

    NASA Astrophysics Data System (ADS)

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

    The NASA Astrophysics Data System (ADS) now holds 1.3 million scanned pages, containing numerous plots and figures for which the original data sets are lost or inaccessible. The availability of scans of the figures can significantly ease the regeneration of the data sets. For this purpose, the ADS has developed Dexter, a Java applet that supports the user in this process. Dexter's basic functionality is to let the user manually digitize a plot by marking points and defining the coordinate transformation from the logical to the physical coordinate system. Advanced features include automatic identification of axes, tracing lines and finding points matching a template. This contribution both describes the operation of Dexter from a user's point of view and discusses some of the architectural issues we faced during implementation.

  12. 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.

  13. Thermodynamic modeling of Pt-Al and Pd-Al

    NASA Astrophysics Data System (ADS)

    Carr, Derek

    2011-03-01

    Pure platinum and pure palladium are too soft for typical jewelry applications. Adding small amounts of other metals can significantly increase their performance. However, international hallmarking standards require the alloys to be 95% pure by weight. How does one achieve significant improvements in performance adding only small amounts (5 wt-%) of other metals? Significant improvements are possible even with small additions if precipitate hardening can be induced. Using a combination of first-principles, cluster expansion, and Monte Carlo modeling, we have identified new Pt-rich/Pd-rich phases in Pt-Al and Pd-Al that should be useful in precipitate hardening. Thermodynamical modeling indicates that the phases are experimentally feasible (not kinetically inhibited).

  14. Strengthening of Al and Al-Mg alloy wires by melt inoculation with Al/MgB2 nanocomposite

    NASA Astrophysics Data System (ADS)

    Florián-Algarín, David; Marrero, Raúl; Padilla, Alexandra; Suárez, Oscar Marcelo

    2015-12-01

    This study hinges on the feasibility of strengthening Al and Al-Mg wires by adding Al nanocomposite pellets containing MgB2 nanoparticles into the melt upon fabrication. These MgB2 nanoparticles were obtained by fragmentation using a high-energy ball mill, and were, afterward, mechanically alloyed with pure aluminum. The resulting MgB2/Al nanocomposite pellets were sintered at 260°C to be subsequently added into molten aluminum and an Al-Mg alloy melt. Cold rolling intercalated with stepwise annealing allowed the fabrication of 1 mm diameter wires with a final area reduction of 96%. Mechanical and physical properties of the treated wire specimens were compared to those of similarly processed pure aluminum wire. The ultimate tensile strength of the treated wires increased approximately double fold with respect to untreated wires at the expense of some loss in electrical conductivity.

  15. Magnetic mass in 4D AdS gravity

    NASA Astrophysics Data System (ADS)

    Araneda, René; Aros, Rodrigo; Miskovic, Olivera; Olea, Rodrigo

    2016-04-01

    We provide a fully covariant expression for the diffeomorphic charge in four-dimensional anti-de Sitter gravity, when the Gauss-Bonnet and Pontryagin terms are added to the action. The couplings of these topological invariants are such that the Weyl tensor and its dual appear in the on-shell variation of the action and such that the action is stationary for asymptotic (anti-)self-dual solutions in the Weyl tensor. In analogy with Euclidean electromagnetism, whenever the self-duality condition is global, both the action and the total charge are identically vanishing. Therefore, for such configurations, the magnetic mass equals the Ashtekhar-Magnon-Das definition.

  16. Canonical energy and hairy AdS black holes

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

    We propose the modified version of the canonical energy which was introduced originally by Hollands and Wald. Our construction depends only on the Euler-Lagrange expression of the system and thus is independent of the ambiguity in the Lagrangian. After some comments on our construction, we briefly mention on the relevance of our construction to the boundary information metric in the context of the AdS/CFT correspondence. We also study the stability of three-dimensional hairy extremal black holes by using our construction.

  17. Lifshitz-like systems and AdS null deformations

    SciTech Connect

    Narayan, K.

    2011-10-15

    Following K. Balasubramanian and K. Narayan [J. High Energy Phys. 08 (2010) 014], we discuss certain lightlike deformations of AdS{sub 5}xX{sup 5} in type IIB string theory sourced by a lightlike dilaton {Phi}(x{sup +}) dual to the N=4 super Yang-Mills theory with a lightlike varying gauge coupling. We argue that, in the case where the x{sup +} direction is noncompact, these solutions describe anisotropic 3+1-dim Lifshitz-like systems with a potential in the x{sup +} direction generated by the lightlike dilaton. We then describe solutions of this sort with a linear dilaton. This enables a detailed calculation of two-point correlation functions of operators dual to bulk scalars and helps illustrate the spatial structure of these theories. Following this, we discuss a nongeometric string construction involving a compactification along the x{sup +} direction of this linear dilaton system. We also point out similar IIB axionic solutions. Similar bulk arguments for x{sup +}-noncompact can be carried out for deformations of AdS{sub 4}xX{sup 7} in M theory.

  18. AdS black holes from duality in gauged supergravity

    NASA Astrophysics Data System (ADS)

    Halmagyi, Nick; Vanel, Thomas

    2014-04-01

    We study and utilize duality transformations in a particular STU-model of four dimensional gauged supergravity. This model is a truncation of the de Wit-Nicolai =8 theory and as such has a lift to eleven-dimensional supergravity on the seven-sphere. Our duality group is U(1)3 and while it can be applied to any solution of this theory, we consider known asymptotically AdS4, supersymmetric black holes and focus on duality transformations which preserve supersymmetry. For static black holes we generalize the supersymmetric solutions of Cacciatori and Klemm from three magnetic charges to include two additional electric charges and argue that this is co-dimension one in the full space of supersymmetric static black holes in the STU-model. These new static black holes have nontrivial profiles for axions. For rotating black holes, we generalize the known two-parameter supersymmetric solution to include an additional parameter. When lifted to M-theory, these black holes correspond to the near horizon geometry of a stack of BPS rotating M2-branes, spinning on an S 7 which is fibered non-trivially over a Riemann surface.

  19. Stability of charged global AdS4 spacetimes

    NASA Astrophysics Data System (ADS)

    Arias, Raúl; Mas, Javier; Serantes, Alexandre

    2016-09-01

    We study linear and nonlinear stability of asymptotically AdS4 solutions in Einstein-Maxwell-scalar theory. After summarizing the set of static solutions we first examine thermodynamical stability in the grand canonical ensemble and the phase transitions that occur among them. In the second part of the paper we focus on nonlinear stability in the microcanonical ensemble by evolving radial perturbations numerically. We find hints of an instability corner for vanishingly small perturbations of the same kind as the ones present in the uncharged case. Collapses are avoided, instead, if the charge and mass of the perturbations come to close the line of solitons. Finally we examine the soliton solutions. The linear spectrum of normal modes is not resonant and instability turns on at extrema of the mass curve. Linear stability extends to nonlinear stability up to some threshold for the amplitude of the perturbation. Beyond that, the soliton is destroyed and collapses to a hairy black hole. The relative width of this stability band scales down with the charge Q, and does not survive the blow up limit to a planar geometry.

  20. The ADS All Sky Survey

    NASA Astrophysics Data System (ADS)

    Goodman, Alyssa

    We will create the first interactive sky map of astronomers' understanding of the Universe over time. We will accomplish this goal by turning the NASA Astrophysics Data System (ADS), widely known for its unrivaled value as a literature resource, into a data resource. GIS and GPS systems have made it commonplace to see and explore information about goings-on on Earth in the context of maps and timelines. Our proposal shows an example of a program that lets a user explore which countries have been mentioned in the New York Times, on what dates, and in what kinds of articles. By analogy, the goal of our project is to enable this kind of exploration-on the sky-for the full corpus of astrophysical literature available through ADS. Our group's expertise and collaborations uniquely position us to create this interactive sky map of the literature, which we call the "ADS All-Sky Survey." To create this survey, here are the principal steps we need to follow. First, by analogy to "geotagging," we will "astrotag," the ADS literature. Many "astrotags" effectively already exist, thanks to curation efforts at both CDS and NED. These efforts have created links to "source" positions on the sky associated with each of the millions of articles in the ADS. Our collaboration with ADS and CDS will let us automatically extract astrotags for all existing and future ADS holdings. The new ADS Labs, which our group helps to develop, includes the ability for researchers to filter article search results using a variety of "facets" (e.g. sources, keywords, authors, observatories, etc.). Using only extracted astrotags and facets, we can create functionality like what is described in the Times example above: we can offer a map of the density of positions' "mentions" on the sky, filterable by the properties of those mentions. Using this map, researchers will be able to interactively, visually, discover what regions have been studied for what reasons, at what times, and by whom. Second, where

  1. Condom ads slated for TV.

    PubMed

    1987-02-20

    3 CBS-owned television stations and NBC's New York television station announced yesterday that they would begin accepting condom advertising. In addition, the ABC network announced it will begin running a 30-second public service message with Dr. C. Everett Koop, the US surgeon general, saying that condoms are the best protection against sexual transmission of AIDS. CBS said it will allow the 4 television stations and 18 radio stations it owns to accept condom advertising based on the attitudes of the local viewing or listening community. WCBS-TV in New York, WCAU-TV in Philadelphia and KCBS-TV in Los Angeles said they would accept such ads. CBS also owns a television station in Chicago. WCAU will air condom ads after 11 p.m. only, beginning probably next week, said Paul Webb, a station spokesman. "We recognize the legitimate sensitivities of some members of the community in regard to this issue," said Steve Cohen, the WCAU general manager. "However, it is the judgment of this station that the importance of providing information about the AIDS epidemic and means of prevention is an overriding consideration." NBC's New York television station, WNBC, announced that it will accept condom advertising and public service announcements. PMID:12269166

  2. 78 FR 19718 - Modifications To Labeling of Nicotine Replacement Therapy Products for Over-the-Counter Human Use

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-02

    ... Therapeutics, 78(6):689-96, 2005. 2. Benowitz, N.L., et al., ``Suppression of Nicotine Intake During Ad Libitum... Prevention, ``Quitting Smoking Among Adults--United States, 2001-2010,'' , Morbidity and Mortality...

  3. Self-Separation of Sublimation-Grown AlN with AlSiN Buffer Layer

    NASA Astrophysics Data System (ADS)

    Nishino, Katsushi; Nakauchi, Jun; Hayashi, Kotaro; Tsukihara, Masashi

    2013-08-01

    AlN was grown by a sublimation method on 6H-SiC. We found the grown AlN layer is easily separated from the substrate when Si powder is added to the AlN source powder. The formation of AlSiN layer with the Si content of 15% at the AlN/6H-SiC interface was confirmed by energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). This AlSiN layer causes the separation of AlN.

  4. The New York Times ad.

    PubMed

    Hunt, M E; Kissling, F

    1993-01-01

    Feminization of patriarchal institutions is necessary in order to eliminate the exclusivity and mutuality of hierarchical, gender, class, and race stratification. The aim of this paper is to explain the history and activities surrounding the New York Times ad on Sunday, October 7, 1984 (the Catholic Statement on Pluralism and Abortion signed by Barbara Ferraro and Patricia Hussey of the Sisters of Note Dame de Namur, Rose Dominic Trapasso of the Maryknoll Sisters, and 67 other signers). The significance of this ad for Roman Catholic feminists and suggestions for new models of relationships between feminists is given. The Statement was written by Daniel Maguire and Frances Kissling and reviewed by 20 Roman Catholic ethicists. A sponsoring committee of early signers sought other support. Catholics for a Free Choice sponsored the funding for circulation of the Statement among professional societies, but not necessarily canonical communities. Publication of the entire statement in the Times was at the height of the presidential campaign. Conservative Bishops Bernard Law of Boston and John O'Connor of Boston publicly denounced Ferraro's position. The first institutional church response came on November 14, 1984, and stated that the Statement was personal opinion and contradictory to clear and constant church teachings about abortion. On November 30, 1984, Cardinal Jean Jerome Hamer of the Congregation for Religious and Secular Institutes responded to most presidents of canonical communities to request a public retraction from signers under threat of dismissal. The issue was obedience to the church. Several members of the canonical community and priests published retractions; negotiations with the Vatican began. Freedom of conscience and empowerment of canonical communities, as agents of their own lives, were given as reasons for the challenge to paternalism. The response was that women were subject to obedience within their communities and had taken public vows and were

  5. Myths & Facts about Value-Added Analysis

    ERIC Educational Resources Information Center

    TNTP, 2011

    2011-01-01

    This paper presents myths as well as facts about value-added analysis. These myths include: (1) "Value-added isn't fair to teachers who work in high-need schools, where students tend to lag far behind academically"; (2) "Value-added scores are too volatile from year-to-year to be trusted"; (3) "There's no research behind value-added"; (4) "Using…

  6. Condom ads promote illicit sex.

    PubMed

    Kippley, J F

    1994-01-01

    Written in 1987, this opinion was republished in the wake of US President Bill Clinton's AIDS prevention media campaign promoting condom use which began January 1994, targeted at young adults aged 18-25. The author staunchly opposes condom use even though he admits that people do not consider abstinence from sex to be a serious option for the prevention of HIV/STD infection. He believes that there is no moral use of sex with a condom and that condoms have always been a sign of immorality, be it prostitution, adultery, fornication, or marital contraception. Likewise, the author laments the success enjoyed by Planned Parenthood in achieving the social acceptance of marital contraception and sex outside of marriage. The complete social acceptance of homosexual activity, however, remains to be achieved. Magazines, newspapers, and television receive income in exchange for publishing or airing advertisements. Finding offensive advertisements which promote the use of condoms against HIV infection, the author recommends writing letters of complaint to the responsible media sources. If the television stations or publications in question continue to advertise condoms to the public, stop watching them or end one's subscriptions to the particular printed media. Such action taken collectively among many individuals will reduce product sales and income, and potentially sway corporate policy against condom ads. PMID:12345946

  7. Condom ads promote illicit sex.

    PubMed

    Kippley, J F

    1994-01-01

    Written in 1987, this opinion was republished in the wake of US President Bill Clinton's AIDS prevention media campaign promoting condom use which began January 1994, targeted at young adults aged 18-25. The author staunchly opposes condom use even though he admits that people do not consider abstinence from sex to be a serious option for the prevention of HIV/STD infection. He believes that there is no moral use of sex with a condom and that condoms have always been a sign of immorality, be it prostitution, adultery, fornication, or marital contraception. Likewise, the author laments the success enjoyed by Planned Parenthood in achieving the social acceptance of marital contraception and sex outside of marriage. The complete social acceptance of homosexual activity, however, remains to be achieved. Magazines, newspapers, and television receive income in exchange for publishing or airing advertisements. Finding offensive advertisements which promote the use of condoms against HIV infection, the author recommends writing letters of complaint to the responsible media sources. If the television stations or publications in question continue to advertise condoms to the public, stop watching them or end one's subscriptions to the particular printed media. Such action taken collectively among many individuals will reduce product sales and income, and potentially sway corporate policy against condom ads.

  8. 27 CFR 19.456 - Adding denaturants.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Adding denaturants. 19.456... Denaturation § 19.456 Adding denaturants. Denaturants and spirits shall be mixed in packages, tanks, or bulk... proprietor shall submit a flow diagram of the intended process or method of adding denaturants. (Sec....

  9. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...

  10. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...

  11. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...

  12. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...

  13. 16 CFR 460.18 - Insulation ads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...

  14. New Features in the ADS Abstract Service

    NASA Technical Reports Server (NTRS)

    Eichhorn, Guenther; Accomazzi, Alberto; Grant, Carolyn S.; Kurtz, Michael J.; Henneken, Edwin A.; Thompson, Donna M.; Murray, Stephen S.

    2005-01-01

    The NASA-ADS Abstract Service provides a sophisticated search capability for the literature in Astronomy, Planetary Sciences, Physics/Geophysics, and Space Instrumentation. The ADS is funded by NASA and access to the ADS services is free to anybody world-wide without restrictions. It allows the user to search the literature by author, title, and abstract text.

  15. Value Added and Other Related Matters.

    ERIC Educational Resources Information Center

    Whitla, Dean K.

    The term "value added" refers to the assessment of the amount of learning that takes place during the college years. Two experiments, Value Added I and Value Added II, attempted to measure college students' attainment of eight liberal education objectives: (1) writing ability; (2) analytical ability; (3) sensitivity to ethics, morals, and values;…

  16. High energy QCD from Planckian scattering in AdS space and the Froissart bound

    SciTech Connect

    Kang, Kyungsik; Nastase, Horatiu

    2005-11-15

    We reanalyze high-energy QCD scattering regimes from scattering in cutoff AdS space via gravity-gauge dualities (a la Polchinski-Strassler). We look at 't Hooft scattering, Regge behavior, and black hole creation in AdS space. Black hole creation in the gravity dual is analyzed via gravitational shockwave collisions. We prove the saturation of the QCD Froissart unitarity bound, corresponding to the creation of black holes of AdS size, as suggested by Giddings.

  17. Removal of Aluminum from Leaching Solution of Lepidolite by Adding Ammonium

    NASA Astrophysics Data System (ADS)

    Li, Huan; Kuang, Ge; Hu, Song; Guo, Hui; Jin, Ran; Vekariya, Rohit L.

    2016-08-01

    Lepidolite is a kind of low-grade lithium ore (3.5-4.0% Li2O) which contains more than 22% Al2O3 and 8% K2O. Removal and utilization of the Al and K will be very important for the economic extraction of lithium from this ore. In this paper, a novel method is proposed to remove Al from the leaching solution of lepidolite by adding ammonium from (NH4)2SO4. The results indicate that adding NH4 + could remove more aluminum and have a smaller loss of lithium in comparison to adding K+ for removing aluminum in the leaching solution. The Al removal reached up to 80.44% at (K+ + NH4 +)/Al3+ molar ratio of 0.95, while the amount of Li+ (99.84%) still remained in the leaching solution. In addition, the phase equilibrium in the quaternary K2SO4-Al2(SO4)3-(NH4)2SO4-H2O system at 278.2 K was investigated to support the above conclusion. The results verify that the addition of ammonium could remove more Al3+ by easily forming potassium alum (KAl(SO4)2·12H2O) and ammonium alum (NH4Al(SO4)2·12H2O).

  18. Removal of Aluminum from Leaching Solution of Lepidolite by Adding Ammonium

    NASA Astrophysics Data System (ADS)

    Li, Huan; Kuang, Ge; Hu, Song; Guo, Hui; Jin, Ran; Vekariya, Rohit L.

    2016-10-01

    Lepidolite is a kind of low-grade lithium ore (3.5-4.0% Li2O) which contains more than 22% Al2O3 and 8% K2O. Removal and utilization of the Al and K will be very important for the economic extraction of lithium from this ore. In this paper, a novel method is proposed to remove Al from the leaching solution of lepidolite by adding ammonium from (NH4)2SO4. The results indicate that adding NH4 + could remove more aluminum and have a smaller loss of lithium in comparison to adding K+ for removing aluminum in the leaching solution. The Al removal reached up to 80.44% at (K+ + NH4 +)/Al3+ molar ratio of 0.95, while the amount of Li+ (99.84%) still remained in the leaching solution. In addition, the phase equilibrium in the quaternary K2SO4-Al2(SO4)3-(NH4)2SO4-H2O system at 278.2 K was investigated to support the above conclusion. The results verify that the addition of ammonium could remove more Al3+ by easily forming potassium alum (KAl(SO4)2·12H2O) and ammonium alum (NH4Al(SO4)2·12H2O).

  19. Appetite and food intake after consumption of sausages with 10% fat and added wheat or rye bran.

    PubMed

    Vuholm, Stine; Jakobsen, Louise Margrethe; Sørensen, Karina Vejrum; Kehlet, Ursula; Raben, Anne; Kristensen, Mette

    2013-10-25

    The use of dietary fibers as fat-replacers in sausages gives less energy-dense and thereby healthier foods. Also, dietary fibers have been shown to induce satiety. The objectives of this study were to investigate if appetite sensations and energy intake was affected by (1) addition of dietary fibers to sausages, (2) type of dietary fibers and (3) the food matrix of the dietary fibers. In this randomized cross-over study 25 young men were served four test meals; wheat bran sausages, rye bran sausages, rye bran bread and wheat flour sausages. The test meals were served as breakfast after an overnight fast. Appetite sensations were evaluated by visual analogue scales (VAS) assessed every 30 minutes for 240 minutes followed by an ad libitum lunch meal where energy intake was calculated. Both rye bran and wheat bran sausages increased satiety (P < 0.01) and fullness (P < 0.02) and decreased hunger (P < 0.001) and prospective consumption (P < 0.001) compared to wheat flour sausages. Furthermore, rye bran sausages increased satiety (P < 0.05) and fullness (P < 0.02) and decreased prospective consumption (P < 0.01) compared to rye bran bread. No differences in subsequent energy intake were observed. In conclusion, wheat and rye bran added to sausages decreased appetite sensations and thereby has a potential added health benefit beyond the role as fat-replacer. The satisfying effect of dietary fibers appears to be more pronounced when added to sausages than when added to bread, stressing the importance of food matrix and food processing.

  20. Appetite and food intake after consumption of sausages with 10% fat and added wheat or rye bran.

    PubMed

    Vuholm, Stine; Jakobsen, Louise Margrethe; Sørensen, Karina Vejrum; Kehlet, Ursula; Raben, Anne; Kristensen, Mette

    2013-10-25

    The use of dietary fibers as fat-replacers in sausages gives less energy-dense and thereby healthier foods. Also, dietary fibers have been shown to induce satiety. The objectives of this study were to investigate if appetite sensations and energy intake was affected by (1) addition of dietary fibers to sausages, (2) type of dietary fibers and (3) the food matrix of the dietary fibers. In this randomized cross-over study 25 young men were served four test meals; wheat bran sausages, rye bran sausages, rye bran bread and wheat flour sausages. The test meals were served as breakfast after an overnight fast. Appetite sensations were evaluated by visual analogue scales (VAS) assessed every 30 minutes for 240 minutes followed by an ad libitum lunch meal where energy intake was calculated. Both rye bran and wheat bran sausages increased satiety (P < 0.01) and fullness (P < 0.02) and decreased hunger (P < 0.001) and prospective consumption (P < 0.001) compared to wheat flour sausages. Furthermore, rye bran sausages increased satiety (P < 0.05) and fullness (P < 0.02) and decreased prospective consumption (P < 0.01) compared to rye bran bread. No differences in subsequent energy intake were observed. In conclusion, wheat and rye bran added to sausages decreased appetite sensations and thereby has a potential added health benefit beyond the role as fat-replacer. The satisfying effect of dietary fibers appears to be more pronounced when added to sausages than when added to bread, stressing the importance of food matrix and food processing. PMID:24512899

  1. Appetite and food intake after consumption of sausages with 10% fat and added wheat or rye bran.

    PubMed

    Vuholm, Stine; Arildsen Jakobsen, Louise Margrethe; Vejrum Sørensen, Karina; Kehlet, Ursula; Raben, Anne; Kristensen, Mette

    2014-02-01

    The use of dietary fibers as fat-replacers in sausages gives less energy-dense and thereby healthier foods. Also, dietary fibers have been shown to induce satiety. The objectives of this study were to investigate if appetite sensations and energy intake was affected by (1) addition of dietary fibers to sausages, (2) type of dietary fibers and (3) the food matrix of the dietary fibers. In this randomized cross-over study 25 young men were served four test meals; wheat bran sausages, rye bran sausages, rye bran bread and wheat flour sausages. The test meals were served as breakfast after an overnight fast. Appetite sensations were evaluated by visual analogue scales (VAS) assessed every 30 min for 240 min followed by an ad libitum lunch meal where energy intake was calculated. Both rye bran and wheat bran sausages increased satiety (P < 0.01) and fullness (P < 0.02) and decreased hunger (P < 0.001) and prospective consumption (P < 0.001) compared to wheat flour sausages. Furthermore, rye bran sausages increased satiety (P < 0.05) and fullness (P < 0.02) and decreased prospective consumption (P < 0.01) compared to rye bran bread. No differences in subsequent energy intake were observed. In conclusion, wheat and rye bran added to sausages decreased appetite sensations and thereby has a potential added health benefit beyond the role as fat-replacer. The satisfying effect of dietary fibers appears to be more pronounced when added to sausages than when added to bread, stressing the importance of food matrix and food processing. PMID:24511620

  2. Appetite and food intake after consumption of sausages with 10% fat and added wheat or rye bran.

    PubMed

    Vuholm, Stine; Arildsen Jakobsen, Louise Margrethe; Vejrum Sørensen, Karina; Kehlet, Ursula; Raben, Anne; Kristensen, Mette

    2014-02-01

    The use of dietary fibers as fat-replacers in sausages gives less energy-dense and thereby healthier foods. Also, dietary fibers have been shown to induce satiety. The objectives of this study were to investigate if appetite sensations and energy intake was affected by (1) addition of dietary fibers to sausages, (2) type of dietary fibers and (3) the food matrix of the dietary fibers. In this randomized cross-over study 25 young men were served four test meals; wheat bran sausages, rye bran sausages, rye bran bread and wheat flour sausages. The test meals were served as breakfast after an overnight fast. Appetite sensations were evaluated by visual analogue scales (VAS) assessed every 30 min for 240 min followed by an ad libitum lunch meal where energy intake was calculated. Both rye bran and wheat bran sausages increased satiety (P < 0.01) and fullness (P < 0.02) and decreased hunger (P < 0.001) and prospective consumption (P < 0.001) compared to wheat flour sausages. Furthermore, rye bran sausages increased satiety (P < 0.05) and fullness (P < 0.02) and decreased prospective consumption (P < 0.01) compared to rye bran bread. No differences in subsequent energy intake were observed. In conclusion, wheat and rye bran added to sausages decreased appetite sensations and thereby has a potential added health benefit beyond the role as fat-replacer. The satisfying effect of dietary fibers appears to be more pronounced when added to sausages than when added to bread, stressing the importance of food matrix and food processing.

  3. The forecaster's added value in QPF

    NASA Astrophysics Data System (ADS)

    Turco, M.; Milelli, M.

    2009-04-01

    To the authors' knowledge there are relatively few studies that try to answer this topic: "Are humans able to add value to computer-generated forecasts and warnings ?". Moreover, the answers are not always positive. In particular some postprocessing method is competitive or superior to human forecast (see for instance Baars et al., 2005, Charba et al., 2002, Doswell C., 2003, Roebber et al., 1996, Sanders F., 1986). Within the alert system of ARPA Piemonte it is possible to study in an objective manner if the human forecaster is able to add value with respect to computer-generated forecasts. Every day the meteorology group of the Centro Funzionale of Regione Piemonte produces the HQPF (Human QPF) in terms of an areal average for each of the 13 regional warning areas, which have been created according to meteo-hydrological criteria. This allows the decision makers to produce an evaluation of the expected effects by comparing these HQPFs with predefined rainfall thresholds. Another important ingredient in this study is the very dense non-GTS network of rain gauges available that makes possible a high resolution verification. In this context the most useful verification approach is the measure of the QPF and HQPF skills by first converting precipitation expressed as continuous amounts into ‘‘exceedance'' categories (yes-no statements indicating whether precipitation equals or exceeds selected thresholds) and then computing the performances for each threshold. In particular in this work we compare the performances of the latest three years of QPF derived from two meteorological models COSMO-I7 (the Italian version of the COSMO Model, a mesoscale model developed in the framework of the COSMO Consortium) and IFS (the ECMWF global model) with the HQPF. In this analysis it is possible to introduce the hypothesis test developed by Hamill (1999), in which a confidence interval is calculated with the bootstrap method in order to establish the real difference between the

  4. LWR (Light Water Reactor) power plant simulations using the AD10 and AD100 systems

    SciTech Connect

    Wulff, W.; Cheng, H.S.; Chien, C.J.; Jang, J.Y.; Lin, H.C.; Mallen, A.N.; Wang, S.J.; Institute of Nuclear Energy Research, Lung-Tan; Tawian Power Co., Taipei; Brookhaven National Lab., Upton, NY; Institute of Nuclear Energy Research, Lung-Tan )

    1989-01-01

    Boiling (BWR) and Pressurized (PWR) Water Reactor Power Plants are being simulated at BNL with the AD10 and AD100 Peripheral Processor Systems. The AD10 system has been used for BWR simulations since 1984 for safety analyses, emergency training and optimization studies. BWR simulation capabilities have been implemented recently on the AD100 system and PWR simulation capabilities are currently being developed under the auspices of international cooperation. Modeling and simulation methods are presented with emphasis on the simulation of the Nuclear Steam Supply System. Results are presented for BWR simulation and performance characteristics are compared of the AD10 and AD100 systems. It will be shown that the AD100 simulates two times faster than two AD10 processors operating in parallel and that the computing capacity of one AD100 (with FMU processor) is twice as large as that of two AD10 processors. 9 refs., 5 figs., 1 tab.

  5. Patrick Moore's millennium yearbook : the view from AD 1001

    NASA Astrophysics Data System (ADS)

    Moore, Patrick, Chapman, Allan

    In a year that will probably be remembered almost as much for books about the millennium as for the turn of 2000 A.D itself, Patrick Moore's Millennium Yearbook celebrates.....well, the wrong millennium! This thoroughly entertaining book - which is for everyone, not just astronomers - contains articles on King Alfred's chronological work, reviews of the new Star Catalogue by the Arab Al-Sufi and the latest edition of Ptolemy's Almagast. And foreshadowing the change to metric units by 1000 years, the book uses arabic numbers instead of Roman - but there is a conversion table if you have trouble with the idea of "zero" and prefer the older system.

  6. Inseparability of photon-added Gaussian states

    SciTech Connect

    Li Hongrong; Li Fuli; Zhu Shiyao

    2007-06-15

    The inseparability of photon-added Gaussian states which are generated from two-mode Gaussian states by adding photons is investigated. According to the established inseparability conditions [New J. Phys. 7, 211 (2005); Phys. Rev. Lett. 96, 050503 (2006)], we find that even if a two-mode Gaussian state is separable, the photon-added Gaussian state becomes entangled when the purity of the Gaussian state is larger than a certain value. The lower bound of entanglement of symmetric photon-added Gaussian states is derived. The result shows that entanglement of the photon-added Gaussian states is involved with high-order moment correlations. We find that fidelity of teleporting coherent states cannot be raised by employing the photon-added Gaussian states as a quantum channel of teleportation.

  7. Micropulse Lidar Cloud Mask Value-Added Product Technical Report

    SciTech Connect

    Sivaraman, C; Comstock, J

    2011-07-25

    Lidar backscattered signal is a useful tool for identifying vertical cloud structure in the atmosphere in optically thin clouds. Cloud boundaries derived from lidar signals are a necessary input for popular ARM data products, such as the Active Remote Sensing of Clouds (ARSCL) product. An operational cloud boundary algorithm (Wang and Sassen 2001) has been implemented for use with the ARM Micropulse Lidar (MPL) systems. In addition to retrieving cloud boundaries above 500 m, the value-added product (VAP) named Micropulse Lidar Cloud Mask (MPLCMASK) applies lidar-specific corrections (i.e., range-square, background, deadtime, and overlap) as described in Campbell et al. (2002) to the measured backscattered lidar. Depolarization ratio is computed using the methodology developed by Flynn et al. (2007) for polarization-capable MPL systems. The cloud boundaries output from MPLCMASK will be the primary lidar cloud mask for input to the ARSCL product and will be applied to all MPL systems, including historical data sets.

  8. Solar activity around AD 775 from aurorae and radiocarbon

    NASA Astrophysics Data System (ADS)

    Neuhäuser, R.; Neuhäuser, D. L.

    2015-04-01

    discuss two more Schwabe cycles until AD {˜ 844}. The 14C record (from both Intcal and Miyake et al. 2013a) is anti-correlated to auroral and sunspot activity, as expected from solar wind modulation of cosmic rays which produce the radiocarbon.

  9. Akhawayni (?-983 AD): A Persian neuropsychiatrist in the early medieval era (9th-12th Century AD).

    PubMed

    Zargaran, Arman; Kordafshari, Gholamreza; Hosseini, Seyyed Rouhollah; Mehdizadeh, Alireza

    2016-05-01

    The early medieval era is also called the Islamic Golden Age because of the significant rise in sciences, including medicine. Abū Bakr Rabi' ibn Ahmad Akhawayni Bukhāri (better known as Akhawayni) was one of the notable medical practitioners in his lifetime. His fame was in neuroscience and he became known as Pezeshk-e-Divanegan (Physician to the Insane). His only surviving book, Hidāyat al-Muta'allimin fi al-Tibb (The Students' Handbook of Medicine), is the first medical textbook in Persian, after Islam. Akhawayni gathered and categorized available knowledge on neuropsychiatry and added his own. He was the first to describe sleep paralysis and to suggest pragmatic rather than supernatural treatment. He was also the first to present fever cure and his descriptions of meningitis (Lisarghos in Hidāyat), mania, psychosis (Malikhulia), dementia (Ghotrab), etc., are close to current concepts. PMID:24658213

  10. On shape dependence of holographic entanglement entropy in AdS4/CFT3

    NASA Astrophysics Data System (ADS)

    Fonda, Piermarco; Seminara, Domenico; Tonni, Erik

    2015-12-01

    We study the finite term of the holographic entanglement entropy of finite domains with smooth shapes and for four dimensional gravitational backgrounds. Analytic expressions depending on the unit vectors normal to the minimal area surface are obtained for both stationary and time dependent spacetimes. The special cases of AdS4, asymptotically AdS4 black holes, domain wall geometries and Vaidya-AdS backgrounds have been analysed explicitly. When the bulk spacetime is AdS4, the finite term is the Willmore energy of the minimal area surface viewed as a submanifold of the three dimensional flat Euclidean space. For the static spacetimes, some numerical checks involving spatial regions delimited by ellipses and non convex domains have been performed. In the case of AdS4, the infinite wedge has been also considered, recovering the known analytic formula for the coefficient of the logarithmic divergence.

  11. Kaon Decays from AdS/QCD

    SciTech Connect

    Schvellinger, Martin

    2008-07-28

    We briefly review one of the current applications of the AdS/CFT correspondence known as AdS/QCD and discuss about the calculation of four-point quark-flavour current correlation functions and their applications to the calculation of observables related to neutral kaon decays and neutral kaon mixing processes.

  12. Next-Generation A/D Sampler ADS3000+ for VLBI2010

    NASA Technical Reports Server (NTRS)

    Takefuji, Kazuhiro; Takeuchi, Hiroshi; Tsutsumi, Masanori; Koyama, Yasuhiro

    2010-01-01

    A high-speed A/D sampler, called ADS3000+, has been developed in 2008, which can sample one analog signal up to 4 Gbps to versatile Linux PC. After A/D conversion, the ADS3000+ can perform digital signal processing such as real-time DBBC (Digital Base Band Conversion) and FIR filtering such as simple CW RFI filtering using the installed FPGAs. A 4 Gsps fringe test with the ADS3000+ has been successfully performed. The ADS3000+ will not exclusively be used for VLBI but will also be employed in other applications.

  13. An improved AFS phase for AdS3 string integrability

    NASA Astrophysics Data System (ADS)

    Abbott, Michael C.; Aniceto, Inês

    2015-04-01

    We propose a number of modifications to the classical term in the dressing phase for integrable strings in AdS3 ×S3 ×S3 ×S1, and check these against existing perturbative calculations, crossing symmetry, and the semiclassical limit of the Bethe equations. The principal change is that the phase for different masses should start with a term Q1Q2, like the one-loop AdS3 dressing phase, rather than Q2Q3 as for the original AdS5 AFS phase.

  14. On circular strings in (AdS3 × S 3)ϰ

    NASA Astrophysics Data System (ADS)

    Banerjee, Aritra; Panigrahi, Kamal L.

    2016-09-01

    The so called one-parameter (often called ϰ) deformed AdS string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the (AdS3 × S 3) ϰ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the ϰ-deformed AdS3 and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.

  15. The eleven observations of comets between 687 AD and 1114 AD recorded in the Anglo Saxon Chronicle

    NASA Technical Reports Server (NTRS)

    Mardon, E. G.; Williams, J.; Mardon, A. A.

    1992-01-01

    This research paper is an examination of the eleven cometary references (679AD, 729AD, 892AD, 950AD, 975AD, 995AD, 1066AD, 1097AD, 1106AD, 1110AD and 1114AD) found in the various manuscripts of The Anglo Saxon Chronicle between 678 AD and 1114 AD. The manuscripts contain more than 35 celestial observations. This is an examination of astronomical phenomena and other climatic or natural events, that are described in The Anglo Saxon Chronicle, which is also referred to as The Old English Annals.

  16. Inflation in AdS/CFT

    SciTech Connect

    Freivogel, Ben; Hubeny, Veronika E.; Maloney, Alexander; Myers, Rob; Rangamani, Mukund; Shenker, Stephen; /Stanford U., Phys. Dept.

    2005-10-07

    We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.

  17. Superradiance instability of small rotating AdS black holes in arbitrary dimensions

    NASA Astrophysics Data System (ADS)

    Delice, Ã.-zgür; Durǧut, Türküler

    2015-07-01

    We investigate the stability of D dimensional singly rotating Myers-Perry-AdS black holes under superradiance against scalar field perturbations. It is well known that small four dimensional rotating or charged Anti-de Sitter (AdS) black holes are unstable against superradiance instability of a scalar field. Recent works extended the existence of this instability to five dimensional rotating charged AdS black holes or static charged AdS black holes in arbitrary dimensions. In this paper we analytically prove that rotating small AdS black holes in arbitrary dimensions also shows superradiance instability irrespective of the value of the (positive) angular momentum quantum number. To do this we solve the Klein-Gordon equation in the slow rotation, low frequency limit. By using the asymptotic matching technique, we are able to calculate the real and imaginary parts of the correction terms to the frequency of the scalar field due to the presence of the black hole, confirming the presence of superradiance instability. We see that, unlike in the case of static AdS black holes, the analytical method is valid for rotating AdS black holes for any value of angular momentum number and spacetime dimensions. For comparison we derive the corresponding correction terms for Myers-Perry black holes in the black hole bomb formalism in the Appendix and see that the results are in agreement.

  18. Supergravity background of the λ-deformed AdS3 × S3 supercoset

    NASA Astrophysics Data System (ADS)

    Chervonyi, Yuri; Lunin, Oleg

    2016-09-01

    We construct the solution of type IIB supergravity describing the integrable λ-deformation of the AdS3 ×S3 supercoset. While the geometry corresponding to the deformation of the bosonic coset has been found in the past, our background is more natural for studying superstrings, and several interesting features distinguish our solution from its bosonic counterpart. We also report progress towards constructing the λ-deformation of the AdS5 ×S5 supercoset.

  19. Studies on the ADS/CFT correspondence

    NASA Astrophysics Data System (ADS)

    Muck, Wolfgang

    1999-11-01

    This thesis summarizes original research on the topic of the ``AdS/CFT correspondence.'' This correspondence, which was first conjectured by Maldacena [ Adv. Theor. Math. Phys. 2, 231 (1998)] and subsequently formulated by Gubser, Klebanov and Polyakov [Phys. Lett. B 428, 105 (1998) and by Witten [Adv. Theor. Math. Phys. 2, 253 (1998)], relates field theories on (d + 1)-dimensional anti-de Sitter (AdS) spaces and conformal field theories (CFTs) in d dimensions with each other. Its main prediction is that the correlation functions of certain quantum CFTs are determined by the dynamics of classical field theories on AdS spaces. Starting from a correspondence formula provided by the authors above, several CFT correlation functions are calculated and agreement with the forms dictated by conformal invariance is found. The necessary renormalization is carried out in the ``ɛ- prescription.'' Details of renormalization and the breaking of conformal symmetries in special cases are investigated by means of the example of the scalar field. The ``asymptotic prescription'' is used to prove a suggestion by Klebanov and Witten [hep- th/9905104] about the treatment of irregular boundary conditions valid to all orders of perturbation theory. The treatment of AdS gravity, which enables the calculation of correlation functions of CFT energy momentum tensors, is carried out in the time slicing formalism. The calculated two-point functions and Weyl anomalies agree with results known from pure CFT considerations. The Wess Zumino model on AdS4 is discussed as an example containing supersymmetry. It is shown that the model yields the correlation functions of conformal fields belonging to a d = 3, N = 1 superconformal multiplet.

  20. Genes Might Explain Hispanics' Added Longevity

    MedlinePlus

    ... University of California, Los Angeles. For example, the biological clock measured Hispanic women's "genetic" age as 2. ... and how long they live," he added. The biological clock used in the new study evaluates the ...

  1. Underweight Seniors May Have Added Alzheimer's Risk

    MedlinePlus

    ... fullstory_160278.html Underweight Seniors May Have Added Alzheimer's Risk Study links lower body weight to increased ... older adults' risk of the memory-robbing disorder Alzheimer's disease, new research suggests. The study included 280 ...

  2. Heat kernels on cone of AdS2 and k-wound circular Wilson loop in AdS5 × S5 superstring

    NASA Astrophysics Data System (ADS)

    Bergamin, R.; Tseytlin, A. A.

    2016-04-01

    We compute the one-loop world-sheet correction to partition function of {{AdS}}5× {{{S}}}5 superstring that should be representing k-fundamental circular Wilson loop in planar limit. The 2d metric of the minimal surface ending on k-wound circle at the boundary is that of a cone of AdS2 with deficit 2π (1-k). We compute the determinants of 2d fluctuation operators by first constructing heat kernels of scalar and spinor Laplacians on the cone using the Sommerfeld formula. The final expression for the k-dependent part of the one-loop correction has simple integral representation but is different from earlier results.

  3. Junk Food Ads Sway Kids' Preferences

    MedlinePlus

    ... Kids' Preferences Children under 8 most vulnerable to marketing's effects, study says To use the sharing features ... studies. The researchers found that ads and other marketing for products high in sugar or salt have ...

  4. Testing the AdS/CFT Correspondence

    SciTech Connect

    Klebanov, Igor R.

    2008-07-28

    This lecture begins with some history and basic facts about string theory and its connections with strong interactions. Comparisons of stacks of Dirichlet branes with curved backgrounds produced by them are used to motivate the AdS/CFT correspondence between superconformal gauge theory and string theory on a product of Anti-de Sitter space and a compact manifold. The ensuing duality between semi-classical spinning strings and long gauge theory operators is briefly reviewed. We go on to describe a recent test of the AdS/CFT correspondence using the Wilson loop cusp anomaly as a function of the coupling, which also enters dimensions of high-spin operators. Finally, strongly coupled thermal SYM theory is explored via a black hole in 5-dimensional AdS space, which leads to explicit results for its entropy and shear viscosity.

  5. Trust Based Routing in Ad Hoc Network

    NASA Astrophysics Data System (ADS)

    Talati, Mikita V.; Valiveti, Sharada; Kotecha, K.

    Ad Hoc network often termed as an infrastructure-less, self- organized or spontaneous network.The execution and survival of an ad-hoc network is solely dependent upon the cooperative and trusting nature of its nodes. However, this naive dependency on intermediate nodes makes the ad-hoc network vulnerable to passive and active attacks by malicious nodes and cause inflict severe damage. A number of protocols have been developed to secure ad-hoc networks using cryptographic schemes, but all rely on the presence of trust authority. Due to mobility of nodes and limitation of resources in wireless network one interesting research area in MANET is routing. This paper offers various trust models and trust based routing protocols to improve the trustworthiness of the neighborhood.Thus it helps in selecting the most secure and trustworthy route from the available ones for the data transfer.

  6. Adding stress plot function to NASTRAN

    NASA Technical Reports Server (NTRS)

    Katoh, S.

    1978-01-01

    Stress plot function was developed and added to the NASTRAN level 15.5. Computed stress distribution can be displayed by this function, with vectors showing the principal stresses of the finite elements over the specified portions of the structure. NASTRAN is reviewed in the aspect of plotting capabilities. Stress tensor field is examined in preparation of stress display. Then the stress plot function as added to the NASTRAN is described. A sample plotout by this function is shown.

  7. The Mutation SK(ad-3A) Cancels the Dominance of ad-3A+ over ad-3A in the Ascus of Neurospora

    PubMed Central

    Delange, A. M.

    1981-01-01

    A newly induced mutant of Neurospora, when crossed with an ad-3A mutant, produces asci with four viable black and four inviable white ascospores. The survivors always contain the new mutant allele, never ad-3A. The new allele, which is called SK(ad-3A) (for spore killer of ad-3A), is located at or very near the ad-3A locus.—In crosses homozygous for ad-3A, each ascus contains only inviable white ascospores. This defect in ascospore maturation is complemented by the wild-type allele, ad-3A+ (crosses heterozygous for ad-3A and ad-3A+ produce mainly viable ascospores), but it is not complemented by the new SK(ad-3A) allele (all ad-3A ascospores from crosses heterozygous for SK(ad-3A) and ad-3A are white and inviable). In crosses homozygous for SK(ad-3A) or heterozygous for SK(ad-3A) and ad-3A+, each ascus contains only viable black ascospores. SK(ad-3A) does not require adenine for growth, and forced heterokaryons between SK(ad-3A) and ad-3A grow at wild-type rates and produce conidia of both genotypes with approximately equal frequency. Thus, the action of SK(ad-3A) is apparently restricted to ascospore formation. Possible mechanisms of the action of this new allele are discussed. PMID:6456169

  8. Image Ads and Issue Ads in U.S. Presidential Advertising: Using Videostyle To Explore Stylistic Differences in Televised Political Ads From 1952 to 2000.

    ERIC Educational Resources Information Center

    Johnston, Anne; Kaid, Lynda Lee

    2002-01-01

    Explores the differences in techniques, strategies, narratives, and symbols used in 1,213 television issue ads and image ads from 13 U.S. presidential campaigns. Concludes that although the majority of both types of ads were positive, negative appeals dominated a higher percentage of issue ads as compared with image ads. (SG)

  9. Comment on the scaling function in AdS4 × Bbb CBbb P3

    NASA Astrophysics Data System (ADS)

    Gromov, Nikolay; Mikhaylov, Victor

    2009-04-01

    The folded spinning string in AdS3 gives us an important insight into AdS/CFT duality. Recently its one-loop energy was analyzed in the context of AdS4/CFT3 by McLoughlin and Roiban arXiv:0807.3965, by Alday, Arutyunov and Bykov arXiv:0807.4400 and by Krishnan arXiv:0807.4561. They computed the spectrum of the fluctuations around the classical solution. In this paper we reproduce their results using the algebraic curve technique and show that under some natural resummation of the fluctuation energies the one-loop energy agrees perfectly with the predictions of arXiv:0807.0777. This provides a further support of the all-loop Bethe equations and of the AdS4 × Bbb CBbb P3 algebraic curve developed in arXiv:0807.0437.

  10. AdS5×S(5) mirror model as a string sigma model.

    PubMed

    Arutyunov, Gleb; van Tongeren, Stijn J

    2014-12-31

    Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally. PMID:25615306

  11. Supersymmetric black holes in AdS4 from very special geometry

    NASA Astrophysics Data System (ADS)

    Gnecchi, Alessandra; Halmagyi, Nick

    2014-04-01

    Supersymmetric black holes in AdS spacetime are inherently interesting for the AdS/CFT correspondence. Within a four dimensional gauged supergravity theory coupled to vector multiplets, the only analytic solutions for regular, supersymmetric, static black holes in AdS4 are those in the STU-model due to Cacciatori and Klemm. We study a class of U (1)-gauged supergravity theories coupled to vector multiplets which have a cubic prepotential, the scalar manifold is then a very special Kähler manifold. When the resulting very special Kähler manifold is a homogeneous space, we find analytic solutions for static, supersymmetric AdS4 black holes with vanishing axions. The horizon geometries of our solutions are constant curvature Riemann surfaces of arbitrary genus.

  12. AdS5×S(5) mirror model as a string sigma model.

    PubMed

    Arutyunov, Gleb; van Tongeren, Stijn J

    2014-12-31

    Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally.

  13. Higher spin contributions to holographic fluid dynamics in AdS5/CFT4

    NASA Astrophysics Data System (ADS)

    Lee, Seungjin; Polyakov, Dimitri

    2014-08-01

    We calculate the graviton's β function in the AdS string-theoretic sigma model, perturbed by vertex operators for Vasiliev's higher spin gauge fields in AdS5. The result is given by βmn=Rmn+4Tmn(g ,u) (with the AdS radius set to 1 and the graviton polarized along the AdS5 boundary), with the matter stress-energy tensor given by that of conformal holographic fluid in d =4, evaluated at the temperature given by T =1/π. The stress-energy tensor is given by Tmn=gmn+4umun+∑NTmn(N) where u is the vector excitation satisfying u2=-1 and N is the order of the gradient expansion in the dissipative part of the tensor. We calculate the contributions up to N =2. The higher spin excitations contribute to the β function, ensuring the overall Weyl covariance of the matter stress tensor. We conjecture that the structure of gradient expansion in d =4 conformal hydrodynamics at higher orders is controlled by the higher spin operator algebra in AdS5.

  14. AdS and Lifshitz scalar hairy black holes in Gauss-Bonnet gravity

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Fan, Zhong-Ying; Zhu, Lu-Yao

    2016-09-01

    We consider Gauss-Bonnet (GB) gravity in general dimensions, which is nonminimally coupled to a scalar field. By choosing a scalar potential of the type V (ϕ )=2 Λ0+1/2 m2ϕ2+γ4ϕ4 , we first obtain large classes of scalar hairy black holes with spherical/hyperbolic/planar topologies that are asymptotic to locally anti- de Sitter (AdS) space-times. We derive the first law of black hole thermodynamics using Wald formalism. In particular, for one class of the solutions, the scalar hair forms a thermodynamic conjugate with the graviton and nontrivially contributes to the thermodynamical first law. We observe that except for one class of the planar black holes, all these solutions are constructed at the critical point of GB gravity where there exist unique AdS vacua. In fact, a Lifshitz vacuum is also allowed at the critical point. We then construct many new classes of neutral and charged Lifshitz black hole solutions for an either minimally or nonminimally coupled scalar and derive the thermodynamical first laws. We also obtain new classes of exact dynamical AdS and Lifshitz solutions which describe radiating white holes. The solutions eventually become AdS or Lifshitz vacua at late retarded times. However, for one class of the solutions, the final state is an AdS space-time with a globally naked singularity.

  15. Behavioral analysis of Wistar rats fed with a flaxseed based diet added to an environmental enrichment.

    PubMed

    Azevedo de Meneses, J; Junqueira Lopes, C A; Coca Velarde, L G; Teles Boaventura, G

    2011-01-01

    Flaxseed has a high content of n-3 fatty acids and its intake associated with an environmental enrichment may promote distinct behavioral results upon habituation and animal behavior. This work aimed to evaluating animal behavior under the use of these two tools in the Open Field Test. Thirty-six male Wistar rats were divided into 6 groups (n = 6): FEEG, receiving chow made up of flaxseed and kept in enriched environment; FSEG, receiving flaxseed based diet and kept in a standard environment; CEEG, receiving casein based diet and kept in enriched environment; CSEG, receiving casein based chow and kept in standard environment; MCEEG, receiving chow made up of casein but modified so as to provide the same content of fibers and lipids found in flaxseed diet and kept in enriched environment; MCSEG, receiving modified casein based diet and kept in standard environment. All animals were kept under controlled temperature, collective cages and dark/light cycle, receiving chow and water ad libitum, except for MCEEG and MCSEG, which were pair fed with FEEG and FSEG, respectively. Chow intake and animal body weight were evaluated twice in a week. Animals were maintained in these groups from the first until the second month of life, by the time when 3 day tests in Open Field Test began. Finishing the tests, animals were sacrificed and their brains were obtained in order to calculate the relative brain weight. Our results show an interplay between flaxseed and environmental enrichment in habituation to a new environment, making the animals more manageable and less stressed.

  16. Spinning strings at one-loop in AdS4 × Bbb P3

    NASA Astrophysics Data System (ADS)

    McLoughlin, Tristan; Roiban, Radu

    2008-12-01

    We analyze the folded spinning string in AdS4 × Bbb P3 with spin S in AdS4 and angular momentum J in Bbb P3. We calculate the one-loop correction to its energy in the scaling limit of both ln S and J large with their ratio kept fixed. This result should correspond to the first subleading strong coupling correction to the anomalous dimension of operators of the type Tr(DS(Y†Y)J) in the dual Script N = 6 Chern-Simons-matter theory. Our result appears to depart from the predictions for the generalized scaling function found from the all-loop Bethe equations conjectured for this AdS4/CFT3 duality. We comment on the possible origin of this difference.

  17. A stochasticity threshold in holography and the instability of AdS

    NASA Astrophysics Data System (ADS)

    Basu, Pallab; Krishnan, Chethan; Saurabh, Ayush

    2015-07-01

    We give strong numerical evidence that a self-interacting probe scalar field in AdS, with only a few modes turned on initially, will undergo fast thermalization only if it is above a certain energetic threshold. Below the threshold the energy stays close to constant in a few modes for a very long time instead of cascading quickly. This indicates the existence of a Strong Stochasticity Threshold (SST) in holography. The idea of SST is familiar from certain statistical mechanical systems, and we suggest that it exists also in AdS gravity. This would naturally reconcile the generic nonlinear instability of AdS observed by Bizon and Rostworowski, with the Fermi-Pasta-Ulam-Tsingou-like quasiperiodicity noticed recently for some classes of initial conditions. We show that our simple setup captures many of the relevant features of the full gravity-scalar system.

  18. QCD Condensates and Holographic Wilson Loops for Asymptotically AdS Spaces

    SciTech Connect

    Quevedo, R. Carcasses; Goity, Jose L.; Trinchero, Roberto C.

    2014-02-01

    The minimization of the Nambu-Goto (NG) action for a surface whose contour defines a circular Wilson loop of radius a placed at a finite value of the coordinate orthogonal to the border is considered. This is done for asymptotically AdS spaces. The condensates of dimension n = 2, 4, 6, 8, and 10 are calculated in terms of the coefficients in the expansion in powers of the radius a of the on-shell subtracted NG action for small a->0. The subtraction employed is such that it presents no conflict with conformal invariance in the AdS case and need not introduce an additional infrared scale for the case of confining geometries. It is shown that the UV value of the gluon condensates is universal in the sense that it only depends on the first coefficients of the difference with the AdS case.

  19. Asymptotically AdS Solutions of Five Dimensional Gravity-Dilaton Theory

    NASA Astrophysics Data System (ADS)

    Nata Atmaja, Ardian

    2016-08-01

    We search for Asymptotically AdS solutions of the background metric in which dilaton back reacts to gravity in five-dimensional gravity-dilaton theory. The five-dimensional gravity-dilaton theory generally appears in the context of the low energy effective action of closed string theory in the Einstein frame. In particular, we consider dilaton which are minimally coupled to gravity in which the potential for dilation is taken to be simple and contain only one exponential term parametrized by a constant a. We solve analytically and show for a simple constant dilaton potential it appears there are no black hole solutions if we turn on the dilaton contribution. On the other hand, the exponential dilaton potential has black hole solutions but they are not in general Asymptotically AdS. We argue that there are some possible Asymptotically AdS black hole solutions in the range of |a| \\lt \\frac{4}{\\sqrt{6}}

  20. Superstring theory on AdS 2× S2 as a coset supermanifold

    NASA Astrophysics Data System (ADS)

    Berkovits, N.; Bershadsky, M.; Hauer, T.; Zhukov, S.; Zwiebach, B.

    We quantize the superstring on the AdS 2× S2 background with Ramond-Ramond flux using a PSU(1,1|2)/ U(1)× U(1) sigma model with a WZ term. One-loop conformal invariance of the model is guaranteed by a general mechanism which holds for coset spaces G/ H where G is Ricci-flat and H is the invariant locus of a Z4 automorphism of G. This mechanism gives conformal theories for the PSU(1,1|2)× PSU(2|2)/ SU(2)× SU(2) and PSU(2,2|4)/ SO(4,1)× SO(5) coset spaces, suggesting our results might be useful for quantizing the superstring on AdS 3× S3 and AdS 5× S5 backgrounds.

  1. Photon gas thermodynamics in dS and AdS momentum spaces

    NASA Astrophysics Data System (ADS)

    Gorji, M. A.; Hosseinzadeh, V.; Nozari, K.; Vakili, B.

    2016-07-01

    In this paper, we study thermostatistical properties of a photon gas in the framework of two deformed special relativity models defined by the cosmological coordinatizations of the de Sitter (dS) and anti-de Sitter (AdS) momentum spaces. The dS model is a doubly special relativity theory in which an ultraviolet length scale is invariant under the deformed Lorentz transformations. For the case of the AdS model, however, the Lorentz symmetry breaks at the high energy regime. We show that the existence of a maximal momentum in dS momentum space leads to maximal pressure and temperature at the thermodynamical level, while maximal internal energy and entropy arise for the case of the AdS momentum space due to the existence of a maximal kinematical energy. These results show that the thermodynamical duality of these models is very similar to their well-known kinematical duality.

  2. Interpolating from Bianchi attractors to Lifshitz and AdS spacetimes

    NASA Astrophysics Data System (ADS)

    Kachru, Shamit; Kundu, Nilay; Saha, Arpan; Samanta, Rickmoy; Trivedi, Sandip P.

    2014-03-01

    We construct classes of smooth metrics which interpolate from Bianchi attractor geometries of Types II, III, VI and IX in the IR to Lifshitz or AdS 2 × S 3 geometries in the UV. While we do not obtain these metrics as solutions of Einstein gravity coupled to a simple matter field theory, we show that the matter sector stress-energy required to support these geometries (via the Einstein equations) does satisfy the weak, and therefore also the null, energy condition. Since Lifshitz or AdS 2 × S 3 geometries can in turn be connected to AdS 5 spacetime, our results show that there is no barrier, at least at the level of the energy conditions, for solutions to arise connecting these Bianchi attractor geometries to AdS 5 spacetime. The asymptotic AdS 5 spacetime has no non-normalizable metric deformation turned on, which suggests that furthermore, the Bianchi attractor geometries can be the IR geometries dual to field theories living in flat space, with the breaking of symmetries being either spontaneous or due to sources for other fields. Finally, we show that for a large class of flows which connect two Bianchi attractors, a C-function can be defined which is monotonically decreasing from the UV to the IR as long as the null energy condition is satisfied. However, except for special examples of Bianchi attractors (including AdS space), this function does not attain a finite and non-vanishing constant value at the end points.

  3. Computing and Using Metrics in the ADS

    NASA Astrophysics Data System (ADS)

    Henneken, E. A.; Accomazzi, A.; Kurtz, M. J.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Holachek, A.; Murray, S. S.

    2015-04-01

    Finding measures for research impact, be it for individuals, institutions, instruments, or projects, has gained a lot of popularity. There are more papers written than ever on new impact measures, and problems with existing measures are being pointed out on a regular basis. Funding agencies require impact statistics in their reports, job candidates incorporate them in their resumes, and publication metrics have even been used in at least one recent court case. To support this need for research impact indicators, the SAO/NASA Astrophysics Data System (ADS) has developed a service that provides a broad overview of various impact measures. In this paper we discuss how the ADS can be used to quench the thirst for impact measures. We will also discuss a couple of the lesser-known indicators in the metrics overview and the main issues to be aware of when compiling publication-based metrics in the ADS, namely author name ambiguity and citation incompleteness.

  4. Flowing along the edge: Spinning up black holes in AdS spacetimes with test particles

    NASA Astrophysics Data System (ADS)

    Rocha, Jorge V.; Santarelli, Raphael

    2014-03-01

    We investigate the consequences of throwing point particles into odd-dimensional Myers-Perry black holes in asymptotically anti-de Sitter (AdS) backgrounds. We restrict our attention to the case in which the angular momenta of the background geometry are all equal. This process allows us to test the generalization of the weak cosmic censorship conjecture to asymptotically AdS spacetimes in higher dimensions. We find no evidence for overspinning in D =5,7,9 and 11 dimensions. Instead, test particles carrying the maximum possible angular momentum that still fall into an extremal rotating black hole generate a flow along the curve of extremal solutions.

  5. FAST TRACK COMMUNICATION: The hidden symmetry of higher dimensional Kerr NUT AdS spacetimes

    NASA Astrophysics Data System (ADS)

    Kubiznák, David; Frolov, Valeri P.

    2007-02-01

    It is well known that four-dimensional Kerr NUT AdS spacetime possesses the hidden symmetry associated with the Killing Yano tensor. This tensor is 'universal' in the sense that there exist coordinates where it does not depend on any of the free parameters of the metric. Recently, the general higher dimensional Kerr NUT AdS solutions of the Einstein equations were obtained. We demonstrate that all these metrics with arbitrary rotation and NUT parameters admit a universal Killing Yano tensor. We give an explicit presentation of the Killing Yano tensor and associated second rank Killing tensor and briefly discuss their properties.

  6. {{AdS}}_{3}/{{CFT}}_{2} and q-Poincaré superalgebras

    NASA Astrophysics Data System (ADS)

    Strömwall, Joakim; Torrielli, Alessandro

    2016-10-01

    We discover that a certain deformation of the 1+1 dimensional Poincaré superalgebra is exactly realised in the massless sector of the {{AdS}}3/{{CFT}}2 integrable scattering problem. Deformed Poincaré superalgebras were previously noticed to appear in the {{AdS}}5/{{CFT}}4 correspondence—which displays only massive excitations, but they were there only a partial symmetry. We obtain a representation of the boost operator and its coproduct, and show that the comultiplication exactly satisfies the homomorphism property. We present a classical limit, and finally speculate on an analogy with the physics of phonons.

  7. New Features in the ADS Abstract Service

    NASA Astrophysics Data System (ADS)

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

    2001-11-01

    The ADS Abstract Service contains over 2.3 million references in four databases: Astronomy/Astrophysics/Planetary Sciences, Instrumentation, Physics/Geophysics, and Preprints. We provide abstracts and articles free to the astronomical community for all major and many smaller astronomy journals, PhD theses, conference proceedings, and technical reports. These four databases can be queried either separately of jointly. The ADS also has scanned 1.3 million pages in 180,000 articles in the ADS Article Service. This literature archive contains all major Astronomy journals and many smaller journals, as well as conference proceedings, including the abstract books from all the LPSCs back to volume 2. A new feature gives our users the ability to see list of articles that were also read by the readers of a given article. This is a powerful tool to find out what current articles are relevant in a particular field of study. We have recently expanded the citation and reference query capabilities. It allows our users to select papers for which they want to see references or citations and then retrieve these citations/references. Another new capability is the ability to sort a list of articles by their citation count. As usual, users should be reminded that the citations in ADS are incomplete because we do not obtain reference lists from all publishers. In addition, we cannot match all references (e.g. in press, private communications, author errors, some conference papers, etc.). Anyone using the citations for analysis of publishing records should keep this in mind. More work on expanding the citation and reference features is planned over the next year. ADS Home Page http://ads.harvard.edu/

  8. Offset compensation for A/D converters

    NASA Technical Reports Server (NTRS)

    Brokl, S. S.; Hurd, W. J.

    1979-01-01

    Analog-to-digital (A/D) converter eliminates dc offset in final digitized signal as well as in analog input by using digital feedback for compensation. Circuit could prove useful in data processing applications in which analog-format data are entered at high rates, as in point-of-sale data input systems.

  9. Value-Added Modeling in Physical Education

    ERIC Educational Resources Information Center

    Hushman, Glenn; Hushman, Carolyn

    2015-01-01

    The educational reform movement in the United States has resulted in a variety of states moving toward a system of value-added modeling (VAM) to measure a teacher's contribution to student achievement. Recently, many states have begun using VAM scores as part of a larger system to evaluate teacher performance. In the past decade, only "core…

  10. Fitting Value-Added Models in R

    ERIC Educational Resources Information Center

    Doran, Harold C.; Lockwood, J. R.

    2006-01-01

    Value-added models of student achievement have received widespread attention in light of the current test-based accountability movement. These models use longitudinal growth modeling techniques to identify effective schools or teachers based upon the results of changes in student achievement test scores. Given their increasing popularity, this…

  11. Adding a Statistical Wrench to the "Toolbox"

    ERIC Educational Resources Information Center

    DesJardins, Stephen L.; Lindsay, Nathan K.

    2008-01-01

    This paper demonstrates a formal statistical test that can be used to help researchers make decisions about alternative statistical model specifications. This test is commonly used by researchers who would like to test whether adding new variables to a model improves the model fit. However, we demonstrate that this formal test can also be employed…

  12. "Value Added" Gauge of Teaching Probed

    ERIC Educational Resources Information Center

    Viadero, Debra

    2009-01-01

    A new study by a public and labor economist suggests that "value added" methods for determining the effectiveness of classroom teachers are built on some shaky assumptions and may be misleading. The study, due to be published in February in the "Quarterly Journal of Economics," is the first of a handful of papers now in the publishing pipeline…

  13. Double relaxation via AdS/CFT

    NASA Astrophysics Data System (ADS)

    Amiri-Sharifi, S.; Ali-Akbari, M.; Kishani-Farahani, A.; Shafie, N.

    2016-08-01

    We exploit the AdS/CFT correspondence to investigate thermalization in an N = 2 strongly coupled gauge theory including massless fundamental matter (quark). More precisely, we consider the response of a zero temperature state of the gauge theory under influence of an external electric field which leads to a time-dependent current. The holographic dual of the above set-up is given by introducing a time-dependent electric field on the probe D7-brane embedded in an AdS5 ×S5 background. In the dual gravity theory an apparent horizon forms on the brane which, according to AdS/CFT dictionary, is the counterpart of the thermalization process in the gauge theory side. We classify different functions for time-dependent electric field and study their effect on the apparent horizon formation. In the case of pulse functions, where the electric field varies from zero to zero, apart from non-equilibrium phase, we observe the formation of two separate apparent horizons on the brane. This means that the state of the gauge theory experiences two different temperature regimes during its time evolution.

  14. Imago Mundi, Imago AD, Imago ADNI

    PubMed Central

    2014-01-01

    Since the launch in 2003 of the Alzheimer’s Disease Neuroimaging Initiative (ADNI) in the USA, ever growing, similarly oriented consortia have been organized and assembled around the world. The various accomplishments of ADNI have contributed substantially to a better understanding of the underlying physiopathology of aging and Alzheimer’s disease (AD). These accomplishments are basically predicated in the trinity of multimodality, standardization and sharing. This multimodality approach can now better identify those subjects with AD-specific traits that are more likely to present cognitive decline in the near future and that might represent the best candidates for smaller but more efficient therapeutic trials – trials that, through gained and shared knowledge, can be more focused on a specific target or a specific stage of the disease process. In summary, data generated from ADNI have helped elucidate some of the pathophysiological mechanisms underpinning aging and AD pathology, while contributing to the international effort in setting the groundwork for biomarker discovery and establishing standards for early diagnosis of AD. PMID:25478022

  15. Adding Users to the Website Design Process

    ERIC Educational Resources Information Center

    Tomeo, Megan L.

    2012-01-01

    Alden Library began redesigning its website over a year ago. Throughout the redesign process the students, faculty, and staff that make up the user base were added to the conversation by utilizing several usability test methods. This article focuses on the usability testing conducted at Alden Library and delves into future usability testing, which…

  16. The AD Nurse: Prepared to be Prepared

    ERIC Educational Resources Information Center

    Beverly, Lynne; Junker, Mary H.

    1977-01-01

    It is not enough for the new associate degree (AD) nursing graduate to know the theory and be willing to learn. She must also have some skill in providing basic nursing care. Examples of applicants, both ADNs and BSNs, are described to illustrate the nursing talent necessary to practice sensitively and effectively. (Editor/TA)

  17. Value Added School Review Field Guide

    ERIC Educational Resources Information Center

    Alberta Education, 2009

    2009-01-01

    The "Value-Added School Review (VSR)" is an analytical model designed to assist schools in identifying and addressing opportunities for school improvement. The model works best when it is focused purposefully on students and the student learning outcomes as defined in the "Guide to Education". It complements the processes described in Alberta…

  18. "Value Added" Proves Beneficial to Teacher Prep

    ERIC Educational Resources Information Center

    Sawchuk, Stephen

    2012-01-01

    The use of "value added" information appears poised to expand into the nation's teacher colleges, with more than a dozen states planning to use the technique to analyze how graduates of training programs fare in classrooms. Supporters say the data could help determine which teacher education pathways produce teachers who are at least as…

  19. Drag force in AdS/CFT

    SciTech Connect

    Gubser, Steven S.

    2006-12-15

    The AdS/CFT correspondence and a classical test string approximation are used to calculate the drag force on an external quark moving in a thermal plasma of N=4 super-Yang-Mills theory. This computation is motivated by the phenomenon of jet-quenching in relativistic heavy ion collisions.

  20. Cutting Budget Corners While Adding Value.

    ERIC Educational Resources Information Center

    Veile, Craig N.; Carpenter, Mark J.

    2000-01-01

    Discusses how one school district saved money while adding long- term value to its capital improvement project. Planning issues involving square footage requirements, quality of material to be used, and heating and cooling system selection are discussed as are concepts to increase student learning capacity for the same construction dollars. (GR)

  1. Anomaly Detection Techniques for Ad Hoc Networks

    ERIC Educational Resources Information Center

    Cai, Chaoli

    2009-01-01

    Anomaly detection is an important and indispensable aspect of any computer security mechanism. Ad hoc and mobile networks consist of a number of peer mobile nodes that are capable of communicating with each other absent a fixed infrastructure. Arbitrary node movements and lack of centralized control make them vulnerable to a wide variety of…

  2. Value-Added Analysis in Instruction

    ERIC Educational Resources Information Center

    Nicholson, Michael R.; Brown, Jeffrey R.

    2010-01-01

    Value-added data provide a viable alternative for gauging school effectiveness--one virtually free of the confounding effects of student demographics and other factors relating to student learning. How is it different from other measuring methods? It concentrates on growth, rather than attainment. This strengthens the concept and measurement of…

  3. Adding Test Generation to the Teaching Machine

    ERIC Educational Resources Information Center

    Bruce-Lockhart, Michael; Norvell, Theodore; Crescenzi, Pierluigi

    2009-01-01

    We propose an extension of the Teaching Machine project, called Quiz Generator, that allows instructors to produce assessment quizzes in the field of algorithm and data structures quite easily. This extension makes use of visualization techniques and is based on new features of the Teaching Machine that allow third-party visualizers to be added as…

  4. Measured Activities of Al and Ni in gamma-(Ni) and gamma'-(Ni)3Al in the Ni-Al-Pt System

    NASA Technical Reports Server (NTRS)

    Copland, Evan

    2007-01-01

    Adding Pt to Ni-Al coatings is critical to achieving the required oxidation protection of Ni-based superalloys, but the nature of the Pt effect remains unresolved. This research provides a fundamental part of the answer by measuring the influence of Pt on the activities of Al and Ni in gamma-(Ni), gamma prime-(Ni)3Al and liquid in the Ni-Al-Pt system. Measurements have been made at 25 compositions in the Ni-rich corner over the temperature range, T = 1400-1750 K, by the vapor pressure technique with a multiple effusion-cell mass spectrometer (multi-cell KEMS). These measurements clearly show adding Pt (for X(sub Pt) less than 0.25) decreases a(Al) while increasing a(Ni). This solution behavior supports the idea that Pt increases Al transport to an alloy / Al2O3 interface and also limits the interaction between the coating and substrate alloys in the gamma-(Ni) + gamma prime-(Ni)3Al region. This presentation will review the progress of this study.

  5. Holographic Hydrodynamics with Baryon Chemical Potential for Charged AdS Black Hole

    SciTech Connect

    Takeuchi, Shingo

    2009-12-15

    We work out the decoupling problem and hydrodynamic analysis for the sound mode in charged AdS black hole and calculate the sound velocity, the charge susceptibility and the electrical conductivity. We find that Einstein relation among the conductivity, the diffusion constant and the susceptibility holds exactly.

  6. Avoiding Ad Avoidance: Factors Affecting the Perception of Online Banner Ads

    ERIC Educational Resources Information Center

    Portnoy, Felix

    2012-01-01

    This dissertation examined the effect of search type, ad saliency, and ad repetition on the perception of online banner advertisements. In the first study, 48 student participants conducted simulated search tasks using mixed factorial design where search type (known-item vs. exploratory) was manipulated within-subject and the banner saliency level…

  7. Designing added functions in engineered cementitious composites

    NASA Astrophysics Data System (ADS)

    Yang, En-Hua

    In this dissertation, a new and systematic material design approach is developed for ECC with added functions through material microstructures linkage to composite macroscopic behavior. The thesis research embodies theoretical development by building on previous ECC micromechanical models, and experimental investigations into three specific new versions of ECC with added functions aimed at addressing societal demands of our built infrastructure. Specifically, the theoretical study includes three important ECC modeling elements: Steady-state crack propagation analyses and simulation, predictive accuracy of the fiber bridging constitutive model, and development of the rate-dependent strain-hardening criteria. The first element establishes the steady-state cracking criterion as a fundamental requirement for multiple cracking behavior in brittle matrix composites. The second element improves the accuracy of crack-width prediction in ECC. The third element establishes the micromechanics basis for impact-resistant ECC design. Three new ECCs with added functions were developed and experimentally verified in this thesis research through the enhanced theoretical framework. A green ECC incorporating a large volume of industrial waste was demonstrated to possess reduced crack width and drying shrinkage. The self-healing ECC designed with tight crack width was demonstrated to recover transport and mechanical properties after microcrack damage when exposed to wet and dry cycles. The impact-resistant ECC was demonstrated to retain tensile ductility with increased strength under moderately high strain-rate loading. These new versions of ECC with added functions are expected to contribute greatly to enhancing the sustainability, durability, and safety of civil infrastructure built with ECC. This research establishes the effectiveness of micromechanics-based design and material ingredient tailoring for ECC with added new attributes but without losing its basic tensile ductile

  8. Hairy black holes in AdS5 × S 5

    NASA Astrophysics Data System (ADS)

    Markeviciute, Julija; Santos, Jorge E.

    2016-06-01

    We use numerical methods to exhaustively study a novel family of hairy black hole solutions in AdS5. These solutions can be uplifted to solutions of type IIB supergravity with AdS5 × S 5 asymptotics and are thus expected to play an important role in our understanding of AdS/CFT. We find an intricate phase diagram, with the aforementioned family of hairy black hole solutions branching from the Reissner-Nordström black hole at the onset of the superradiance instability. We analyse black holes with spherical and planar horizon topology and explain how they connect in the phase diagram. Finally, we detail their global and local thermodynamic stability across several ensembles.

  9. 'Abd al-Rahman al-Sufi's 3-Step Magnitude System

    NASA Astrophysics Data System (ADS)

    Hafez, Ihsan; Stephenson, F. Richard; Orchiston, Wayne

    'Abd al-Rahmān al-ūfī's Book of the Fixed Stars dates from around AD 964 and is one of the most important medieval Arabic treatises on astronomy. In this paper we begin with a very brief introduction to the Book of the Fixed Stars. This book contains an extensive star catalogue that lists star coordinates and magnitude estimates for all of the Ptolemaic stars. However, in his book al-hūfī utilized three distinct intermediate magnitude values whereas Ptolemy only mentioned two. We believe that al-hūfī used what we have termed a '3-step intermediate magnitude system,' which is more accurate than Ptolemy's 2-step intermediate system. In this paper we examine in detail the accuracy of this unique 3-step system in comparison with Ptolemy's and modern magnitude values.

  10. Increase of radiocarbon concentration in tree rings from Kujawy (SE Poland) around AD 774-775

    NASA Astrophysics Data System (ADS)

    Rakowski, Andrzej Z.; Krąpiec, Marek; Huels, Mathias; Pawlyta, Jacek; Dreves, Alexander; Meadows, John

    2015-10-01

    Evidence of a rapid increase in atmospheric radiocarbon (14C) content in AD 774-775 was presented by Miyake et al. (2012), who observed an increase of about 12‰ in the 14C content in annual tree rings from Japanese cedar. Usoskin et al. (2013) report a similar 14C spike in German oak, and attribute it to exceptional solar activity. If this phenomenon is global in character, such rapid changes in 14C concentration may affect the accuracy of calibrated dates, as the existing calibration curve is composed mainly of decadal samples. Single-year samples of dendro-chronologically dated tree rings of deciduous oak (Quercus robur) from Kujawy, a village near Krakow (SE Poland), spanning the years AD 765-796, were collected and their 14C content was measured using the AMS system in the Leibniz Laboratory. The results clearly show a rapid increase of 9.2 ± 2.1‰ in the 14C concentration in tree rings between AD 774 and AD 775, with maximum Δ14C = 4.1 ± 2.3‰ noted in AD 776.

  11. AdS/CFT connection between Boltzmann and Einstein equations: Kinetic theory and pure gravity in AdS space

    SciTech Connect

    Iyer, Ramakrishnan; Mukhopadhyay, Ayan

    2010-04-15

    The AdS/CFT correspondence defines a sector with universal strongly coupled dynamics in the field theory as the dual of pure gravity in AdS described by Einstein's equation with a negative cosmological constant. We explain here, from the field-theoretic viewpoint how the dynamics in this sector gets determined by the expectation value of the energy-momentum tensor alone. We first show that the Boltzmann equation has very special solutions which could be functionally completely determined in terms of the energy-momentum tensor alone. We call these solutions conservative solutions. We indicate why conservative solutions should also exist when we refine this kinetic description to go closer to the exact microscopic theory or even move away from the regime of weak coupling so that no kinetic description could be employed. We argue that these conservative solutions form the universal sector dual to pure gravity at strong coupling and large N. Based on this observation, we propose a regularity condition on the energy-momentum tensor so that the dual solution in pure gravity has a smooth future horizon. We also study if irreversibility emerges only at long time scales of observation, unlike the case of the Boltzmann equation.

  12. GENERAL: On particles tunneling from the Taub-NUT-AdS black hole

    NASA Astrophysics Data System (ADS)

    Zeng, Xiao-Xiong; Li, Qiang

    2009-11-01

    This paper discusses tunneling of scalar particles and Dirac particles from the Taub-NUT-AdS black hole by the Hamilton-Jacobi equation, initially used by Angheben et al, and the Dirac equation, recently proposed by Kerner and Mann. This is performed in the dragging coordinate frame so as to avoid the ergosphere dragging effect. A general form is obtained for the temperature of scalar and Dirac particles tunneling from the Taub-NUT-Ads black hole, which is commensurate with other methods as expected.

  13. Searching for events in Chinese ancient records to explain the increase in 14C from AD 774-775 and AD 993-994

    NASA Astrophysics Data System (ADS)

    Chai, Ya-Ting; Zou, Yuan-Chuan

    2015-09-01

    According to analysis of the 14C content in two Japanese trees, that grew over a period of approximately 3000 years, with high time resolution, Miyake et al. found a rapid increase at AD 774-775 and another one at AD 993-994. These increases correspond to high-energy events that happened within those years and radiated γ-ray energy of about 7×1024 erg toward the Earth. The origin of these events is a mystery. Such strong events should have an unusual optical counterpart, and have been recorded in historical literatures. We searched Chinese historical materials around AD 744-775 and AD 993-994, but no remarkable event was found except for a violent thunderstorm in AD 775. However, the possibility of a thunderstorm containing so much energy is unlikely. We conclude that the events, which caused the 14C increase, are still unclear. These events most probably had no optical counterpart, and a short gamma-ray burst, giant flare of a soft gamma-ray repeater or a terrestrial γ-ray flash could all be candidates.

  14. Sex steroid levels and AD-like pathology in 3xTgAD mice.

    PubMed

    Overk, C R; Perez, S E; Ma, C; Taves, M D; Soma, K K; Mufson, E J

    2013-02-01

    Decreases in testosterone and 17β-oestradiol (E(2)) are associated with an increased risk for Alzheimer's disease (AD), which has been attributed to an increase in β-amyloid and tau pathological lesions. Although recent studies have used transgenic animal models to test the effects of sex steroid manipulations on AD-like pathology, almost none have systematically characterised the associations between AD lesions and sex steroid levels in the blood or brain in any mutant model. The present study evaluated age-related changes in testosterone and E(2) concentrations, as well as androgen receptor (AR) and oestrogen receptor (ER) α and β expression, in brain regions displaying AD pathology in intact male and female 3xTgAD and nontransgenic (ntg) mice. We report for the first time that circulating and brain testosterone levels significantly increase in male 3xTgAD mice with age, but without changes in AR-immunoreactive (IR) cell number in the hippocampal CA1 or medial amygdala. The age-related increase in hippocampal testosterone levels correlated positively with increases in the conformational tau isoform, Alz50. These data suggest that the over-expression of human tau up-regulate the hypothalamic-pituitary-gonadal axis in these mice. Although circulating and brain E(2) levels remained stable with age in both male and female 3xTgAD and ntg mice, ER-IR cell number in the hippocampus and medial amygdala decreased with age in female transgenic mice. Furthermore, E(2) levels were significantly higher in the hippocampus than in serum, suggesting local production of E(2). Although triple transgenic mice mimic AD-like pathology, they do not fully replicate changes in human sex steroid levels, and may not be the best model for studying the effects of sex steroids on AD lesions.

  15. The AdS/CFT correspondence

    NASA Astrophysics Data System (ADS)

    Hubeny, Veronika E.

    2015-06-01

    We give a brief review of the AdS/CFT correspondence, which posits the equivalence between a certain gravitational theory and a lower-dimensional non-gravitational one. This remarkable duality, formulated in 1997, has sparked a vigorous research program that has gained in breadth over the years, with applications to many aspects of theoretical (and even experimental) physics, not least to general relativity and quantum gravity. To put the AdS/CFT correspondence into historical context, we start by reviewing the relevant aspects of string theory (of which no prior knowledge is assumed). We then develop the statement of the correspondence, and explain how the two sides of the duality map into each other. Finally, we discuss the implications and applications of the correspondence, and indicate some of the current trends in this subject. The presentation attempts to convey the main concepts in a simple and self-contained manner, relegating supplementary remarks to footnotes.

  16. Supporting Dynamic Ad hoc Collaboration Capabilities

    SciTech Connect

    Agarwal, Deborah A.; Berket, Karlo

    2003-07-14

    Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.

  17. LINAC for ADS application - accelerator technologies

    SciTech Connect

    Garnett, Robert W; Sheffreld, Richard L

    2009-01-01

    Sifnificant high-current, high-intensity accelerator research and development have been done in the recent past in the US, centered primarily at Los Alamos National Laboratory. These efforts have included designs for the Accelerator Production of Tritium Project, Accelerator Transmutation of Waste, and Accelerator Driven Systems, as well as many others. This past work and some specific design principles that were developed to optimie linac designs for ADS and other high-intensity applications will be discussed briefly.

  18. Merged Sounding Value-Added Product

    SciTech Connect

    Troyan, D

    2010-03-03

    The Merged Sounding value-added product (VAP) uses a combination of observations from radiosonde soundings, the microwave radiometer (MWR), surface meteorological instruments, and European Centre for Medium-Range Weather Forecasts (ECMWF) model output with a sophisticated scaling/interpolation/smoothing scheme in order to define profiles of the atmospheric thermodynamic state at one-minute temporal intervals and a total of 266 altitude levels.

  19. ARM KAZR-ARSCL Value Added Product

    DOE Data Explorer

    Jensen, Michael

    2012-09-28

    The Ka-band ARM Zenith Radars (KAZRs) have replaced the long-serving Millimeter Cloud Radars, or MMCRs. Accordingly, the primary MMCR Value Added Product (VAP), the Active Remote Sensing of CLouds (ARSCL) product, is being replaced by a KAZR-based version, the KAZR-ARSCL VAP. KAZR-ARSCL provides cloud boundaries and best-estimate time-height fields of radar moments.

  20. Adding coal dust to coal batch

    SciTech Connect

    V.S. Shved; A.V.Berezin

    2009-05-15

    The granulometric composition of coke dust from the dry-slaking machine is determined. The influence of additions of 3-7% coke dust on the quality of industrial coking batch and the coke obtained by box coking is estimated. Adding 1% coke dust to coking batch does not markedly change the coke quality. Industrial equipment for the supply of dry-slaking dust to the batch is described.

  1. Period-adding route in sparkling bubbles.

    PubMed

    Liger-Belair, Gérard; Tufaile, Alberto; Robillard, Bertrand; Jeandet, Philippe; Sartorelli, José Carlos

    2005-09-01

    Chains of bubbles are seen rising along the wall whenever champagne is poured into a glass. The careful observation of a given bubble chain often reveals that the interbubble distance suddenly changes during the degassing process, indicating different bubbling regimes in this elusive phenomenon of effervescence. We report the transitions between these different bubbling regimes that present sequences of multiple periods known as the period-adding route.

  2. Routing Security in Ad Hoc Wireless Networks

    NASA Astrophysics Data System (ADS)

    Pervaiz, Mohammad O.; Cardei, Mihaela; Wu, Jie

    Wireless networks provide rapid, untethered access to information and computing, eliminating the barriers of distance, time, and location for many applications ranging from collaborative, distributed mobile computing to disaster recovery (such as fire, flood, earthquake), law enforcement (crowd control, search, and rescue), and military communications (command, control, surveillance, and reconnaissance). An ad hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any established infrastructure or centralized administration [11

  3. Bar Impact Tests on Alumina (AD995)

    NASA Astrophysics Data System (ADS)

    Cazamias, James U.; Reinhart, William D.; Konrad, Carl H.; Chhabildas, Lalit C.; Bless, Stephan J.

    2002-07-01

    Dynamic strength may be inferred from bar impact tests, although interpretation of the data is affected by the time-to-failure of the target bar. To clarify the mechanics, tests with graded density impactors were conducted on bare and confined bars, 12 and 19 mm in diameter, cut from blocks of AD995 alumina. Manganin gauge and VISAR diagnostics were employed. Larger rods displayed higher strength. In some tests the "true" yield stress of ˜4.5 GPa was achieved.

  4. ADS: The Next Generation Search Platform

    NASA Astrophysics Data System (ADS)

    Accomazzi, A.; Kurtz, M. J.; Henneken, E. A.; Chyla, R.; Luker, J.; Grant, C. S.; Thompson, D. M.; Holachek, A.; Dave, R.; Murray, S. S.

    2015-04-01

    Four years after the last LISA meeting, the NASA Astrophysics Data System (ADS) finds itself in the middle of major changes to the infrastructure and contents of its database. In this paper we highlight a number of features of great importance to librarians and discuss the additional functionality that we are currently developing. Our citation coverage has doubled since 2010 and now consists of over 10 million citations. We are normalizing the affiliation information in our records and we have started collecting and linking funding sources with papers in our system. At the same time, we are undergoing major technology changes in the ADS platform. We have rolled out and are now enhancing a new high-performance search engine capable of performing full-text as well as metadata searches using an intuitive query language. We are currently able to index acknowledgments, affiliations, citations, and funding sources. While this effort is still ongoing, some of its benefits are already available through the ADS Labs user interface and API at http://adslabs.org/adsabs/.

  5. A new AdS/CFT correspondence

    NASA Astrophysics Data System (ADS)

    Nastase, Horatiu Stefan; Siegel, Warren

    2000-10-01

    We consider a geometric zero-radius limit for strings on AdS5 × S5, where the Anti-de Sitter hyperboloid becomes the projective lightcone. In this limit the fifth dimension becomes non dynamical, yielding a different ``holographic'' interpretation than the usual ``bulk to boundary'' one. When quantized on the random lattice, the fifth coordinate acts as a new kind of Schwinger parameter, producing Feynman rules with normal propagators at the tree level: for example, in the bosonic case ordinary massless phi4 theory is obtained. In the superstring case we obtain new, manifestly Script N = 4 supersymmetric rules for Script N = 4 super Yang-Mills. These gluons are also different from those of the usual AdS/CFT correspondence: they are the ``partons'' that make up the usual ``hadrons'' of the open and closed strings in the familiar QCD string picture. Thus, their coupling gYM and rank N of the ``color'' gauge group are different from those of the ``flavor'' gauge group of the open string. As a result we obtain different perturbation expansions in radius, coupling, and 1/N.

  6. Note: Evidence against 2D-Ising criticality in aqueous solutions with added salt

    NASA Astrophysics Data System (ADS)

    Troncoso, Jacobo; Cerdeiriña, Claudio A.

    2013-11-01

    Coexistence-curve data in the refractive index-temperature plane for solutions of 3-methyl-pyridine in heavy water with a small amount of added sodium tetraphenylborate have been determined. The analysis of such data indicates that this system belongs to the universality class of the three-dimensional Ising model (3D-Ising). This finding contrasts with previous work by Sadakane et al. [Soft Matter 7, 1334 (2011)] in which 2D-Ising criticality is invoked, but agrees with the recent assessment by Leys et al. [Soft Matter 9, 9326 (2013)].

  7. The uptake and speciation of various Al species in the Brassica rapa pekinensis.

    PubMed

    Polak, T B; Milacic, R; Pihlar, B; Mitrović, B

    2001-05-01

    An investigation was carried out on the uptake and speciation of Al species in Al tolerant Chinese cabbage (Brassica rapa L. ssp. pekinensis). Plants were exposed to 10 microg cm(-3) of Al in the chemical forms of Al3+, Al-citrate and Al-malate in a time span from 1 up to 24 h. In each experiment the nutrient solution and stem sap were analysed by a combination of FPLC ICP AES and ES MS MS techniques. Speciation analysis enabled determination of particular chemical forms of Al present in the nutrient solution or in stem sap. The results indicate that Al3+ added to the nutrient solution remained as Al3+ in the solution during the experiments, but in the roots transformation to Al-malate occurred. Al was transported from roots to the upper parts of the plant as Al-malate (70%) and Al3+ (30%). Al-citrate or Al-malate added to the nutrient solution were transferred to the upper parts of the plant without transformation of their chemical forms.

  8. Semiclassical energy of the AdS4 × Bbb CBbb P3 folded string

    NASA Astrophysics Data System (ADS)

    Beccaria, Matteo; Macorini, Guido; Ratti, CarloAlberto; Valatka, Saulius

    2013-01-01

    We consider the classical solution describing a folded type IIA string in the background AdS4 × Bbb CBbb P3. The string is spinning in AdS and has angular momentum in Bbb CBbb P3. In the 't Hooft limit, this is the gravity dual of twist operators in the ABJM superconformal theory. We quantize the classical solution by algebraic curve methods and determine the first semiclassical correction to the energy. An integral representation is given, valid for all values of the charges. We analyze its properties in the special regimes associated with a short or long string. Finally, we investigate various properties of the leading term of the energy for short strings (the so-called slope).

  9. Tensionless supersymmetric M2 branes in AdS4 × S7 and giant diabolo

    NASA Astrophysics Data System (ADS)

    López Carballo, Jaume; Lugo, Adrián R.; Russo, Jorge G.

    2009-11-01

    We find various supersymmetric configurations of toroidal M2 brane solutions in AdS4 × S7 or, more generally, in AdS4 × S7/Bbb Zk. In this class we identify solutions preserving 1/4 and 1/8 supersymmetries of the background. The supersymmetric M2 branes have angular momenta and winding on S7, and null world-volumes. In certain cases they collapse to string-like configurations. These configurations can be viewed as a higher-dimensional (membrane) analog of BMN states. We compute the energy and angular momenta, showing that all supersymmetric configurations obey the BPS relation E = J/R, J≡∑i = 14|Ji| with E,J → ∞. Finally, we also study another class of supersymmetric M2-branes, including uncompact rotating membranes of ``diabolo'' shape.

  10. Renormalization, averaging, conservation laws and AdS (in)stability

    NASA Astrophysics Data System (ADS)

    Craps, Ben; Evnin, Oleg; Vanhoof, Joris

    2015-01-01

    We continue our analytic investigations of non-linear spherically symmetric perturbations around the anti-de Sitter background in gravity-scalar field systems, and focus on conservation laws restricting the (perturbatively) slow drift of energy between the different normal modes due to non-linearities. We discover two conservation laws in addition to the energy conservation previously discussed in relation to AdS instability. A similar set of three conservation laws was previously noted for a self-interacting scalar field in a non-dynamical AdS background, and we highlight the similarities of this system to the fully dynamical case of gravitational instability. The nature of these conservation laws is best understood through an appeal to averaging methods which allow one to derive an effective Lagrangian or Hamiltonian description of the slow energy transfer between the normal modes. The conservation laws in question then follow from explicit symmetries of this averaged effective theory.

  11. Witten diagrams revisited: the AdS geometry of conformal blocks

    NASA Astrophysics Data System (ADS)

    Hijano, Eliot; Kraus, Per; Perlmutter, Eric; Snively, River

    2016-01-01

    We develop a new method for decomposing Witten diagrams into conformal blocks. The steps involved are elementary, requiring no explicit integration, and operate directly in position space. Central to this construction is an appealingly simple answer to the question: what object in AdS computes a conformal block? The answer is a "geodesic Witten diagram", which is essentially an ordinary exchange Witten diagram, except that the cubic vertices are not integrated over all of AdS, but only over bulk geodesics connecting the boundary operators. In particular, we consider the case of four-point functions of scalar operators, and show how to easily reproduce existing results for the relevant conformal blocks in arbitrary dimension.

  12. Integrable open spin-chains in AdS3 /CFT2 correspondences

    NASA Astrophysics Data System (ADS)

    Prinsloo, Andrea; Regelskis, Vidas; Torrielli, Alessandro

    2015-11-01

    We study integrable open boundary conditions for d (2 ,1 ;α )2 and p s u (1 ,1 |2 )2 spin-chains. Magnon excitations of these open spin-chains are mapped to massive excitations of type-IIB open superstrings ending on D-branes in the AdS3×S3×S3×S1 and AdS3×S3×T4 supergravity geometries with pure R-R flux. We derive reflection matrix solutions of the boundary Yang-Baxter equation which intertwine representations of a variety of boundary coideal subalgebras of the bulk Hopf superalgebra. Many of these integrable boundaries are matched to D1- and D5-brane maximal giant gravitons.

  13. Massive quiver matrix models for massive charged particles in AdS

    DOE PAGES

    Asplund, Curtis T.; Denef, Frederik; Dzienkowski, Eric

    2016-01-11

    Here, we present a new class of N = 4 supersymmetric quiver matrix models and argue that it describes the stringy low-energy dynamics of internally wrapped D-branes in four-dimensional anti-de Sitter (AdS) flux compactifications. The Lagrangians of these models differ from previously studied quiver matrix models by the presence of mass terms, associated with the AdS gravitational potential, as well as additional terms dictated by supersymmetry. These give rise to dynamical phenomena typically associated with the presence of fluxes, such as fuzzy membranes, internal cyclotron motion and the appearance of confining strings. We also show how these models can bemore » obtained by dimensional reduction of four-dimensional supersymmetric quiver gauge theories on a three-sphere.« less

  14. Witten diagrams revisited: the AdS geometry of conformal blocks

    DOE PAGES

    Hijano, Eliot; Kraus, Per; Perlmutter, Eric; Snively, River

    2016-01-25

    Here, we develop a new method for decomposing blocks. The steps involved are elementary, requiring no explicit integration, and operate directly in position space. Central to this construction is an appealingly simple answer to the question: what object in AdS computes a conformal block? The answer is a "geodesic Witten diagram", which is essentially an ordinary exchange Witten diagram, except that the cubic vertices are not integrated over all of AdS, but only over bulk geodesics connecting the boundary operators. In particular, we also consider the case of four-point functions of scalar operators, and show how to easily reproduce existingmore » results for the relevant conformal blocks in arbitrary dimension.« less

  15. Resolving Some Issues in Using Value-Added Measures of Productivity for School and Teacher Incentives: Ideas from Technical Assistance and TIF Grantee Experience. The Harvesting Project

    ERIC Educational Resources Information Center

    Milanowski, Anthony

    2011-01-01

    Although many researchers and policy analysts (e.g., Harris, Glazerman et al., 2011; 2010) consider value-added to be the state of the art in school and teacher productivity measurement, only a minority of Teacher Incentive Fund (TIF) Round 1 and 2 grantees used value-added as a measure of school or teacher performance. Fourteen of the 34 grantees…

  16. Unfolded equations for massive higher spin supermultiplets in AdS3

    NASA Astrophysics Data System (ADS)

    Buchbinder, I. L.; Snegirev, T. V.; Zinoviev, Yu. M.

    2016-08-01

    In this paper we give an explicit construction of unfolded equations for massive higher spin supermultiplets of the minimal (1, 0) supersymmetry in AdS 3 space. For that purpose we use an unfolded formulation for massive bosonic and fermionic higher spins and find supertransformations leaving appropriate set of unfolded equations invariant. We provide two general supermultiplets ( s, s + 1 /2) and ( s, s - 1 /2) with arbitrary integer s, as well as a number of lower spin examples.

  17. AdS black disk model for small-x DIS

    NASA Astrophysics Data System (ADS)

    Cornalba, Lorenzo; Costa, Miguel S.; Penedones, João

    2011-05-01

    Using the approximate conformal invariance of QCD at high energies we consider a simple AdS black disk model to describe saturation in DIS. Deep inside saturation the structure functions have the same power law scaling, FT˜FL˜x-ω, where ω is related to the expansion rate of the black disk with energy. Furthermore, the ratio FL/FT is given by the universal value 1+ω/3+ω, independently of the target.

  18. Yangian of AdS3 / CFT2 and its deformation

    NASA Astrophysics Data System (ADS)

    Regelskis, Vidas

    2016-08-01

    We construct highest-weight modules and a Yangian extension of the centrally extended sl(1 | 1) 2 superalgebra, that is a symmetry of the worldsheet scattering associated with the AdS3 / CFT2 duality. We demonstrate that the R-matrix intertwining atypical modules has an elegant trigonometric parametrization. We also consider a quantum deformation of this superalgebra, its modules, and obtain a quantum affine extension of the Drinfeld-Jimbo type that describes a deformed worldsheet scattering.

  19. Gaugings of four-dimensional N =3 supergravity and AdS4/CFT3 holography

    NASA Astrophysics Data System (ADS)

    Karndumri, Parinya; Upathambhakul, Khem

    2016-06-01

    We study matter-coupled N =3 gauged supergravity in four dimensions with various semisimple gauge groups. When coupled to n vector multiplets, the gauged supergravity contains 3 +n vector fields and 3 n complex scalars parametrized by S U (3 ,n )/S U (3 )×S U (n )×U (1 ) coset manifold. Semisimple gauge groups take the form of G0×H ⊂S O (3 ,n )⊂S U (3 ,n ) with H being a compact subgroup of S O (n +3 -dim (G0)). The G0 groups considered in this paper are of the form S O (3 ), S O (3 ,1 ), S O (2 ,2 ), S L (3 ,R ) and S O (2 ,1 )×S O (2 ,2 ). We find that S O (3 )×S O (3 ), S O (3 ,1 ) and S L (3 ,R ) gauge groups admit a maximally supersymmetric AdS4 critical point. The S O (2 ,1 )×S O (2 ,2 ) gauge group admits a supersymmetric Minkowski vacuum while the remaining gauge groups admit both half-supersymmetric domain wall vacua and AdS4 vacua with completely broken supersymmetry. For the S O (3 )×S O (3 ) gauge group, there exists another supersymmetric N =3 AdS4 critical point with S O (3 )diag symmetry. We explicitly give a detailed study of various holographic RG flows between AdS4 critical points, flows to nonconformal theories, and supersymmetric domain walls in each gauge group. The results provide gravity duals of N =3 Chern-Simons-matter theories in three dimensions.

  20. New =1 supersymmetric AdS 5 backgrounds in type IIA supergravity

    NASA Astrophysics Data System (ADS)

    Sfetsos, Konstadinos; Thompson, Daniel C.

    2014-11-01

    We present a family of =1 supersymmetric backgrounds in type-IIA super-gravity and their lifts to eleven-dimensional supergravity. These are of the form AdS 5 × X 5 and are characterised by an SU(2) structure. The internal space, X 5, is obtained from the known Sasaki-Einstein manifolds, Y p,q , via an application of non-Abelian T-duality.

  1. ``Short'' spinning strings and structure of quantum AdS5×S5 spectrum

    NASA Astrophysics Data System (ADS)

    Beccaria, M.; Giombi, S.; Macorini, G.; Roiban, R.; Tseytlin, A. A.

    2012-09-01

    Using information from the marginality conditions of vertex operators for the AdS5×S5 superstring, we determine the structure of the dependence of the energy of quantum string states on their conserved charges and the string tension ˜λ. We consider states on the leading Regge trajectory in the flat space limit which carry one or two (equal) spins in AdS5 or S5 and an orbital momentum in S5, with Konishi multiplet states being particular cases. We argue that the coefficients in the energy may be found by using a semiclassical expansion. By analyzing the examples of folded spinning strings in AdS5 and S5, as well as three cases of circular two-spin strings, we demonstrate the universality of transcendental (zeta-function) parts of few leading coefficients. We also show the consistency with target space supersymmetry with different states belonging to the same multiplet having the same nontrivial part of the energy. We suggest, in particular, that a rational coefficient (found by Basso for the folded string using Bethe Ansatz considerations and which, in general, is yet to be determined by a direct two-loop string calculation) should, in fact, be universal.

  2. Entropy of near-extremal black holes in AdS5

    SciTech Connect

    Simon, Joan; Balasubramanian, Vijay; de Boer, Jan; Jejjala, Vishnu; Simon, Joan

    2007-07-24

    We construct the microstates of near-extremal black holes in AdS_5 x S5 as gases of defects distributed in heavy BPS operators in the dual SU(N) Yang-Mills theory. These defects describe open strings on spherical D3-branes in the S5, and we show that they dominate the entropy by directly enumerating them and comparing the results with a partition sum calculation. We display new decoupling limits in which the field theory of the lightest open strings on the D-branes becomes dual to a near-horizon region of the black hole geometry. In the single-charge black hole we find evidence for an infrared duality between SU(N) Yang-Mills theories that exchanges the rank of the gauge group with an R-charge. In the two-charge case (where pairs of branes intersect on a line), the decoupled geometry includes an AdS_3 factor with a two-dimensional CFT dual. The degeneracy in this CFT accounts for the black hole entropy. In the three-charge case (where triples of branes intersect at a point), the decoupled geometry contains an AdS_2 factor. Below a certain critical mass, the two-charge system displays solutions with naked timelike singularities even though they do not violate a BPS bound. We suggest a string theoretic resolution of these singularities.

  3. On elliptic string solutions in AdS3 and dS3

    NASA Astrophysics Data System (ADS)

    Bakas, Ioannis; Pastras, Georgios

    2016-07-01

    Classical string actions in AdS3 and dS3 can be connected to the sinh-Gordon and cosh-Gordon equations through Pohlmeyer reduction. We show that the problem of constructing a classical string solution with a given static or translationally invariant Pohlmeyer counterpart is equivalent to solving four pairs of effective Schrödinger problems. Each pair consists of a flat potential and an n = 1 Lamé potential whose eigenvalues are connected, and, additionally, the four solutions satisfy a set of constraints. An approach for solving this system is developed by employing an interesting connection between the specific class of classical string solutions and the band structure of the Lamé potential. This method is used for the construction of several families of classical string solutions, one of which turns out to be the spiky strings in AdS3. New solutions include circular rotating strings in AdS3 with singular time evolution of their radius and angular velocity as well as classical string solutions in dS3.

  4. Korean nova records in A.D. 1073 and A.D. 1074: R Aquarii

    NASA Astrophysics Data System (ADS)

    Yang, Hong-Jin; Park, Myeong-Gu; Cho, Se-Hyung; Park, Changbom

    2005-05-01

    R Aqr is known to be a symbiotic binary system with an associated extended emission nebula, possibly produced by a historic outburst. To find the associated historic records, we searched for and compiled all Guest Star and Peculiar Star records in three Korean official history books that cover almost two thousand years, Samguksagi, Goryeosa, Joseonwangjosillok. In addition to the record of A.D. 1073, previously noted by Li (1985, Chin. Astron. Astrophys., 9, 322), we have found in Goryeosa another candidate record of A.D. 1074, which has the same positional description as that of A.D. 1073 with an additional brightness description. We examined various aspects of the two records and conclude that they both are likely to be the records of outburst of R Aqr. This means that there were two successive outbursts in A.D. 1073 and in A.D. 1074, separated by approximately one year. Based on these records, we estimate the distance to R Aqr to be 273 pc if the expansion of the nebula has been at a constant rate. The brightness record of A.D. 1074 corresponds to the absolute magnitude at outburst of Moutburst = -6.2m -5.2m at this distance. The two Korean records associated with R Aqr may provide astronomically meaningful constraints to the outburst model of R Aqr and the formative process of its nebulosity.

  5. On AdS to dS transitions in higher-curvature gravity

    NASA Astrophysics Data System (ADS)

    Camanho, Xián O.; Edelstein, José D.; Gomberoff, Andrés; Sierra-Garcıa, J. Anıbal

    2015-10-01

    We study the possible existence of gravitational phase transitions from AdS to dS geometries in the context of higher-curvature gravities. We use Lanczos-Gauss-Bonnet (LGB) theory with a positive cosmological constant as a toy model. This theory has two maximally symmetric vacua with positive (dS) and negative (AdS) constant curvature. We show that a phase transition from the AdS vacuum to a dS black hole geometry takes place when the temperature reaches a critical value. The transition is produced by nucleation of bubbles of the new phase that expand afterwards. We claim that this phenomenon is not particular to the model under study, that contains Boulware-Deser instabilities, but shall also be part of generic gravitational theories with higher-curvature terms, where these problems are absent. A salient feature that emerges when a positive cosmological constant is considered is that the temperature in which these bubbles may form is bounded from above. Thermodynamically this property is related to quite an uncommon feature that this system exhibits, namely, the existence of a zeroth-order phase transition.

  6. [Environmental factors in ALS].

    PubMed

    Juntas-Morales, Raul; Pageot, Nicolas; Corcia, Philippe; Camu, William

    2014-05-01

    ALS is likely to be a disorder of multifactorial origin. Among all the factors that may increase the risk of ALS, environmental ones are being studied for many years, but in the recent years, several advances have pointed to a new interest in their potential involvement in the disease process, especially for the cyanotoxin BMAA. Food containing BMAA has been found on Guam, a well-known focus of ALS/parkinsonism/dementia and high levels of BMAA have been identified into the brain of these patients. The BMAA cyanotoxin is potentially ubiquitous and have also been found into the food of patients who died from ALS both in Europe and USA. BMAA can be wrongly integrated into the protein structure during mRNA traduction, competing with serine. This may induce abnormal protein folding and a subsequent cell death. Heavy metals, such as lead or mercury may be directly toxic for neuronal cells. Several works have suggested an increased risk of ALS in individuals chronically exposed to these metals. Exposure to pesticides has been suggested to be linked to an increased risk of developing ALS. The mechanism of their toxicity is likely to be mediated by paraoxonases. These proteins are in charge of detoxifying the organism from toxins, and particularly organophosphates. To date, there are insufficient scientific data to suggest that exposure to electromagnetic fields may increase the risk of having ALS. We are particularly missing longitudinal cohorts to demonstrate that risk.

  7. Crystalline Al1 - x Ti x phases in the hydrogen cycled NaAlH4 + 0.02TiCl3 system

    NASA Astrophysics Data System (ADS)

    Pitt, M. P.; Vullum, P. E.; Sørby, M. H.; Emerich, H.; Paskevicius, M.; Buckley, C. E.; Gray, E. MacA.; Walmsley, J. C.; Holmestad, R.; Hauback, B. C.

    2013-03-01

    The hydrogen (H) cycled planetary milled (PM) NaAlH4 + 0.02TiCl3 system has been studied by high resolution synchrotron X-ray diffraction and transmission electron microscopy during the first 10 H cycles. After the first H absorption, we observe the formation of four nanoscopic crystalline (c-) Ti-containing phases embedded on the NaAlH4 surface, i.e. Al2Ti, Al3Ti, Al82Ti18 and Al89Ti11, with 100% of the originally added Ti atoms accounted for. Al2Ti and Al3Ti are observed morphologically as a mechanical couple on the NaAlH4 surface, with a moderately strained interface. Electron diffraction shows that the Al82Ti18 phase retains some ordering from the L12 structure type, with the observation of forbidden (100) ordering reflections in the fcc Al82Ti18 lattice. After 2 H cycles the NaAlH4 + 0.02TiCl3 system displays only two crystalline Ti-containing phases, Al3Ti and Al89Ti11. After 10 H cycles, the Al89Ti11 is completely converted to Al85Ti15. Al89Ti11, Al85Ti15 and Al3Ti do not display any ordering reflections, and they are modeled in the A1 structure type. Quantitative phase analysis indicates that the Al3Ti proportion continues to increase with further H cycles. The formation of Ti-poor Al1 - x Ti x (x < 0.25) phases in later H cycles is detrimental to hydrogenation kinetics, compared to the starting Ti-richer near-surface Al2Ti/NaAlH4 interface present during the first absorption of hydrogen.

  8. Vacuum currents in braneworlds on AdS bulk with compact dimensions

    NASA Astrophysics Data System (ADS)

    Bellucci, S.; Saharian, A. A.; Vardanyan, V.

    2015-11-01

    The two-point function and the vacuum expectation value (VEV) of the current density are investigated for a massive charged scalar field with arbitrary curvature coupling in the geometry of a brane on the background of AdS spacetime with partial toroidal compactification. The presence of a gauge field flux, enclosed by compact dimensions, is assumed. On the brane the field obeys Robin boundary condition and along compact dimensions periodicity conditions with general phases are imposed. There is a range in the space of the values for the coefficient in the boundary condition where the Poincaré vacuum is unstable. This range depends on the location of the brane and is different for the regions between the brane and AdS boundary and between the brane and the horizon. In models with compact dimensions the stability condition is less restrictive than that for the AdS bulk with trivial topology. The vacuum charge density and the components of the current along non-compact dimensions vanish. The VEV of the current density along compact dimensions is a periodic function of the gauge field flux with the period equal to the flux quantum. It is decomposed into the boundary-free and brane-induced contributions. The asymptotic behavior of the latter is investigated near the brane, near the AdS boundary and near the horizon. It is shown that, in contrast to the VEVs of the field squared an denergy-momentum tensor, the current density is finite on the brane and vanishes for the special case of Dirichlet boundary condition. Both the boundary-free and brane-induced contributions vanish on the AdS boundary. The brane-induced contribution vanishes on the horizon and for points near the horizon the current is dominated by the boundary-free part. In the near-horizon limit, the latter is connected to the corresponding quantity for a massless field in the Minkowski bulk by a simple conformal relation. Depending on the value of the Robin coefficient, the presence of the brane can either

  9. 37 CFR 2.98 - Adding party to interference.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Adding party to interference....98 Adding party to interference. A party may be added to an interference only upon petition to the... interference is not added, the examiner may suspend action on the application pending termination of...

  10. 7 CFR 58.727 - Adding optional ingredients.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Adding optional ingredients. 58.727 Section 58.727... Procedures § 58.727 Adding optional ingredients. As each batch is added to the cooker, the predetermined amounts of salt, emulsifiers, color, or other allowable optional ingredients shall be added. However,...

  11. 7 CFR 58.727 - Adding optional ingredients.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Adding optional ingredients. 58.727 Section 58.727... Procedures § 58.727 Adding optional ingredients. As each batch is added to the cooker, the predetermined amounts of salt, emulsifiers, color, or other allowable optional ingredients shall be added. However,...

  12. 37 CFR 2.98 - Adding party to interference.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Adding party to interference....98 Adding party to interference. A party may be added to an interference only upon petition to the... interference is not added, the examiner may suspend action on the application pending termination of...

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

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Added poisonous or deleterious substances. 509.6...-PACKAGING MATERIAL General Provisions § 509.6 Added poisonous or deleterious substances. (a) Use of an added... approved under the criteria of section 409 of the act, or when the added poisonous or deleterious...

  14. B₂O₃-added lithium aluminium germanium phosphate solid electrolyte for Li-O₂ rechargeable batteries.

    PubMed

    Jadhav, Harsharaj S; Kalubarme, Ramchandra S; Jang, Seong-Yong; Jung, Kyu-Nam; Shin, Kyoung-Hee; Park, Chan-Jin

    2014-08-14

    B2O3-added Li(1.5)Al(0.5)Ge(1.5)(PO4)3 (LAGP) glass ceramics showing a room temperature ionic conductivity of 0.67 mS cm(-1) have been synthesized by using a melt-quenching method. The prepared glass ceramics are observed to be stable in tetraethylene glycol dimethyl ether containing lithium bis(trifluoromethane) sulfonamide. The augmented conductivity of the B2O3-added LAGP glass ceramic has improved the plateau potential during discharge. Furthermore, the B2O3-added LAGP glass ceramics are successfully employed as a solid electrolyte in a Li-O2 battery to obtain a stable cycling lifetime of up to 15 cycles with the limited capacity protocol.

  15. Interpolated Sounding Value-Added Product

    SciTech Connect

    Troyan, D

    2013-04-01

    The Interpolated Sounding (INTERPSONDE) value-added product (VAP) uses a combination of observations from radiosonde soundings, the microwave radiometer (MWR), and surface meteorological instruments in order to define profiles of the atmospheric thermodynamic state at one-minute temporal intervals and a total of at least 266 altitude levels. This VAP is part of the Merged Sounding (MERGESONDE) suite of VAPs. INTERPSONDE is the profile of the atmospheric thermodynamic state created using the algorithms of MERGESONDE without including the model data from the European Centre for Medium-range Weather Forecasting (ECMWF). More specifically, INTERPSONDE VAP represents an intermediate step within the larger MERGESONDE process.

  16. The NASA ADS: Searching, Linking and More

    NASA Technical Reports Server (NTRS)

    Thompson, D. M.; Eichhorn, G.; Accomazzi, A.; Bohlen, E.; Grant, C. S.; Henneken, E.; Kurtz, M.; Murray, S.

    2004-01-01

    The NASA ADS Abstract Service is a NASA-funded project which provides FREE World Wide Web abstract search services. We currently have over 3.6 million references in four databases: 1) Astronomy and Planetary Sciences; 2) Physics and Geophysics; 3) Space Instrumentation; and 4) Astronomy Preprints. Our eleven mirror sites in France, Germany, Japan, Chile, Great Britain, India, Russia, Brazil, Argentina, Korea and China help to provide better global access. Each database contains abstracts from hundreds of journals, publications, colloquia, symposia, proceedings, PhD Theses, and NASA reports. All abstracts can be searched by author, title, or abstract text words.

  17. Firewalls in AdS/CFT

    NASA Astrophysics Data System (ADS)

    Avery, Steven G.; Chowdhury, Borun D.

    2014-10-01

    Several recent papers argue against firewalls by relaxing the requirement for locality outside the stretched horizon. In the firewall argument, locality essentially serves the purpose of ensuring that the degrees of freedom required for infall are those in the proximity of the black hole and not the ones in the early radiation. We make the firewall argument sharper by utilizing the AdS/CFT framework and claim that the firewall argument essentially states that the dual to a thermal state in the CFT is a firewall.

  18. Adding control to arbitrary unknown quantum operations

    PubMed Central

    Zhou, Xiao-Qi; Ralph, Timothy C.; Kalasuwan, Pruet; Zhang, Mian; Peruzzo, Alberto; Lanyon, Benjamin P.; O'Brien, Jeremy L.

    2011-01-01

    Although quantum computers promise significant advantages, the complexity of quantum algorithms remains a major technological obstacle. We have developed and demonstrated an architecture-independent technique that simplifies adding control qubits to arbitrary quantum operations—a requirement in many quantum algorithms, simulations and metrology. The technique, which is independent of how the operation is done, does not require knowledge of what the operation is, and largely separates the problems of how to implement a quantum operation in the laboratory and how to add a control. Here, we demonstrate an entanglement-based version in a photonic system, realizing a range of different two-qubit gates with high fidelity. PMID:21811242

  19. Noncommutative q -photon-added coherent states

    NASA Astrophysics Data System (ADS)

    Dey, Sanjib; Hussin, Véronique

    2016-05-01

    We construct the photon-added coherent states of a noncommutative harmonic oscillator associated to a q -deformed oscillator algebra. Various nonclassical properties of the corresponding system are explored, first, by studying two different types of higher-order quadrature squeezing, namely, the Hillery type and the Hong-Mandel type, and second, by testing the sub-Poissonian nature of photon statistics in higher order with the help of the correlation function and the Mandel parameter. Also, we compare the behavior of different types of quadrature and photon number squeezing of our system with those of the ordinary harmonic oscillator by considering the same set of parameters.

  20. Non-Repudiation in Ad Hoc Networks

    NASA Astrophysics Data System (ADS)

    Tandel, Purvi; Valiveti, Sharada; Agrawal, K. P.; Kotecha, K.

    With the phenomenal growth of the Internet and open networks in general, security services, such as non-repudiation, become crucial to many applications. In conventional network non-repudiation is achieved using protocols involving TTP. Non-repudiation in conventional network is achieved using different protocols, but in ad hoc networks due to mobility problem we can't use trusted third party (TTP). There is a scope to implement a non-repudiation protocol, which satisfies non-repudiation requirements emerged by the application in a peer-to-peer network.

  1. Microstructural and phase evolution in metakaolin geopolymers with different activators and added aluminosilicate fillers

    NASA Astrophysics Data System (ADS)

    Sarkar, Madhuchhanda; Dana, Kausik; Das, Sukhen

    2015-10-01

    This work aims to investigate the microstructural and phase evolution of alkali activated metakaolin products with different activators and added aluminosilicate filler phases. The added filler phases have different reactivity to the alkali activated metakaolin system. Microstructural evolution in the alkali activated products has been investigated by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Field Emission Scanning Electron Microscope (FESEM). Variation in strength development in alkali activated metakaolin products was followed by compressive strength measurement test. Microstructural study shows that in case of metakaolin with NaOH activator crystalline sodalite formed in all the product samples irrespective of the added filler phases. The microstructure of these NaOH activated products investigated by FESEM showed crystalline and inhomogeneous morphology. Mixed activator containing both NaOH and sodium silicate in a fixed mass ratio formed predominantly amorphous phase. Microstructure of these samples showed more homogeneity than that of NaOH activated metakaolin products. The study further shows that addition of α-Al2O3 powder, non reactive phase to the alkali activated metakaolin system when used in larger amount increased crystalline phase in the matrix. α-Al2O3 powder addition increased the compressive strength of the product samples for both the activator compositions. Added phase of colloidal silica, reactive to the alkali activated metakaolin system when used in larger amount was found to increase amorphous nature of the matrix. Addition of colloidal silica influenced the compressive strength property differently with different activator compositions.

  2. Amyotrophic Lateral Sclerosis (ALS)

    MedlinePlus

    ... Pictures of ALS Mutant Proteins Support Two Major Theories About How the Disease is Caused May 2003 ... All NINDS-prepared information is in the public domain and may be freely copied. Credit to the ...

  3. Genetic Testing for ALS

    MedlinePlus

    ... Involved Donate Familial Amyotrophic Lateral Sclerosis (FALS) and Genetic Testing By Deborah Hartzfeld, MS, CGC, Certified Genetic ... guarantee a person will develop symptoms of ALS. Genetic Counseling If there is more than one person ...

  4. All About ALS

    MedlinePlus

    ... External link, please review our exit disclaimer . Subscribe All About ALS Understanding a Devastating Disorder In the ... a coffee pot, or button a shirt. Eventually, all muscles under voluntary control are affected, and people ...

  5. What Is ALS?

    MedlinePlus

    ... scarring or hardening ("sclerosis") in the region. Motor neurons reach from the brain to the spinal cord ... the body. The progressive degeneration of the motor neurons in ALS eventually leads to their demise. When ...

  6. POSSIBLE CHROMOSPHERIC ACTIVITY CYCLES IN AD LEO

    SciTech Connect

    Buccino, Andrea P.; Petrucci, Romina; Mauas, Pablo J. D.; Jofré, Emiliano

    2014-01-20

    AD Leo (GJ 388) is an active dM3 flare star that has been extensively observed both in the quiescent and flaring states. Since this active star is near the fully convective boundary, studying its long-term chromospheric activity in detail could be an appreciable contribution to dynamo theory. Here, using the Lomb-Scargle periodogram, we analyze the Ca II K line-core fluxes derived from CASLEO spectra obtained between 2001 and 2013 and the V magnitude from the ASAS database between 2004 and 2010. From both of these totally independent time series, we obtain a possible activity cycle with a period of approximately seven years and a less significant shorter cycle of approximately two years. A tentative interpretation is that a dynamo operating near the surface could be generating the longer cycle, while a second dynamo operating in the deep convection zone could be responsible for the shorter one. Based on the long duration of our observing program at CASLEO and the fact that we observe different spectral features simultaneously, we also analyze the relation between simultaneous measurements of the Na I index (R{sub D}{sup ′}), Hα, and Ca II K fluxes at different activity levels of AD Leo, including flares.

  7. AdS flowing black funnels: Stationary AdS black holes with non-Killing horizons and heat transport in the dual CFT

    NASA Astrophysics Data System (ADS)

    Fischetti, Sebastian; Marolf, Donald; Santos, Jorge

    2013-04-01

    We construct stationary non-equilibrium black funnels locally asymptotic to global AdS4 in vacuum Einstein-Hilbert gravity with negative cosmological constant. These are non-compactly-generated black holes in which a single connected bulk horizon extends to meet the conformal boundary. Thus the induced (conformal) boundary metric has smooth horizons as well. In our examples, the boundary spacetime contains a pair of black holes connected through the bulk by a tubular bulk horizon. Taking one boundary black hole to be hotter than the other (δT !=0) prohibits equilibrium. The result is a so-called flowing funnel, a stationary bulk black hole with a non-Killing horizon that may be said to transport heat toward the cooler boundary black hole. While most of our results are numerical, a semi-analytic fluid/gravity description can be obtained by passing to a one-parameter generalization of the above boundary conditions. In the fluid regime, we find excellent agreement with our numerical solutions. In terms of a dual CFT, our solutions describe heat transport via a large N version of Hawking radiation through a deconfined plasma that couples efficiently to both boundary black holes.

  8. OpenAD : algorithm implementation user guide.

    SciTech Connect

    Utke, J.

    2004-05-13

    Research in automatic differentiation has led to a number of tools that implement various approaches and algorithms for the most important programming languages. While all these tools have the same mathematical underpinnings, the actual implementations have little in common and mostly are specialized for a particular programming language, compiler internal representation, or purpose. This specialization does not promote an open test bed for experimentation with new algorithms that arise from exploiting structural properties of numerical codes in a source transformation context. OpenAD is being designed to fill this need by providing a framework that allows for relative ease in the implementation of algorithms that operate on a representation of the numerical kernel of a program. Language independence is achieved by using an intermediate XML format and the abstraction of common compiler analyses in Open-Analysis. The intermediate format is mapped to concrete programming languages via two front/back end combinations. The design allows for reuse and combination of already implemented algorithms. We describe the set of algorithms and basic functionality currently implemented in OpenAD and explain the necessary steps to add a new algorithm to the framework.

  9. Frozen yogurt with added inulin and isomalt.

    PubMed

    Isik, U; Boyacioglu, D; Capanoglu, E; Erdil, D Nilufer

    2011-04-01

    The objective of this study was to produce a frozen yogurt containing low fat and no added sugar. Samples containing 5% polydextrose, 0.065% aspartame and acesulfame-K mixture, and different levels of inulin and isomalt (5.0, 6.5, and 8.0%) were produced at pilot scale and analyzed for their physical and chemical properties including proximate composition, viscosity, acidity, overrun, melting rate, heat shock stability, as well as sensory characteristics, and viability of lactic acid bacteria. With the addition of inulin and isomalt, viscosity increased by 19 to 52% compared with that of sample B (reduced-fat control). The average calorie values of samples substituted with sweeteners were about 43% lower than that of original sample. Low-calorie frozen yogurt samples melted about 33 to 48% slower than the reduced-fat control sample at 45 min. Based on quantitative descriptive profile test results, statistically significant differences among products were observed for hardness, iciness, foamy melting, whey separation, and sweetness characteristics. The results of principal component analysis showed that the sensory properties of the sample containing 6.5% inulin and 6.5% isomalt were similar to those of control. Lactic acid bacteria counts of frozen yogurt were found to be between 8.12 and 8.49 log values, 3 mo after the production. The overall results showed that it is possible to produce an attractive frozen yogurt product with the incorporation of inulin and isomalt with no added sugar and reduced fat.

  10. Extensive genetics of ALS

    PubMed Central

    Calvo, Andrea; Mazzini, Letizia; Cantello, Roberto; Mora, Gabriele; Moglia, Cristina; Corrado, Lucia; D'Alfonso, Sandra; Majounie, Elisa; Renton, Alan; Pisano, Fabrizio; Ossola, Irene; Brunetti, Maura; Traynor, Bryan J.; Restagno, Gabriella

    2012-01-01

    Objective: To assess the frequency and clinical characteristics of patients with mutations of major amyotrophic lateral sclerosis (ALS) genes in a prospectively ascertained, population-based epidemiologic series of cases. Methods: The study population includes all ALS cases diagnosed in Piemonte, Italy, from January 2007 to June 2011. Mutations of SOD1, TARDBP, ANG, FUS, OPTN, and C9ORF72 have been assessed. Results: Out of the 475 patients included in the study, 51 (10.7%) carried a mutation of an ALS-related gene (C9ORF72, 32; SOD1, 10; TARDBP, 7; FUS, 1; OPTN, 1; ANG, none). A positive family history for ALS or frontotemporal dementia (FTD) was found in 46 (9.7%) patients. Thirty-one (67.4%) of the 46 familial cases and 20 (4.7%) of the 429 sporadic cases had a genetic mutation. According to logistic regression modeling, besides a positive family history for ALS or FTD, the chance to carry a genetic mutation was related to the presence of comorbid FTD (odds ratio 3.5; p = 0.001), and age at onset ≤54 years (odds ratio 1.79; p = 0.012). Conclusions: We have found that ∼11% of patients with ALS carry a genetic mutation, with C9ORF72 being the commonest genetic alteration. Comorbid FTD or a young age at onset are strong indicators of a possible genetic origin of the disease. PMID:23100398

  11. Variations of 14C around AD 775 and AD 1795 - due to solar activity

    NASA Astrophysics Data System (ADS)

    Neuhäuser, R.; Neuhäuser, D. L.

    2015-12-01

    The motivation for our study is the disputed cause for the strong variation of 14C around AD 775. Our method is to compare the 14C variation around AD 775 with other periods of strong variability. Our results are: (a) We see three periods, where 14C varied over 200 yr in a special way showing a certain pattern of strong secular variation: after a Grand Minimum with strongly increasing 14C, there is a series of strong short-term drop(s), rise(s), and again drop(s) within 60 yr, ending up to 200 yr after the start of the Grand Minimum. These three periods include the strong rises around BC 671, AD 775, and AD 1795. (b) We show with several solar activity proxies (radioisotopes, sunspots, and aurorae) for the AD 770s and 1790s that such intense rapid 14C increases can be explained by strong rapid decreases in solar activity and, hence, wind, so that the decrease in solar modulation potential leads to an increase in radioisotope production. (c) The strong rises around AD 775 and 1795 are due to three effects, (i) very strong activity in the previous cycles (i.e. very low 14C level), (ii) the declining phase of a very strong Schwabe cycle, and (iii) a phase of very weak activity after the strong 14C rise - very short and/or weak cycle(s) like the suddenly starting Dalton minimum. (d) Furthermore, we can show that the strong change at AD 1795 happened after a pair of two packages of four Schwabe cycles with certain hemispheric leadership (each package consists of two Gnevyshev-Ohl pairs, respectively two Hale-Babcock pairs). We show with several additional arguments that the rise around AD 775 was not that special. We conclude that such large, short-term rises in 14C (around BC 671, AD 775, and 1795) do not need to be explained by highly unlikely solar super-flares nor other rare events, but by extra-solar cosmic rays modulated due to solar activity variations.

  12. Multi-decadal variation in southern California drought during the Medieval Climate Anomaly and Little Ice Age (~800AD-~1800AD) - evidence from coeval terrestrial and marine proxies

    NASA Astrophysics Data System (ADS)

    Heusser, L. E.; Hendy, I. L.; Barron, J. A.; Pak, D. K.

    2012-12-01

    High resolution studies of precipitation proxies (pollen from coastal, drought-resistant chaparral and upslope mesic oak-pine woodlands, and bulk sediment Ti%) from sediments deposited in Santa Barbara Basin (SPR0901-02kc; 34°16.845N, 120°02.332W, water depth 588 m) reflect decadal-scale fluctuations in persistent severe drought spanning from ~800 to 1270AD. Pollen from chamise and manzanita chaparrals (sclerophyllous woody shrubs dominated by Adenostoma and Arctostaphylos) begins to decline at ~1265AD, while oak-pine woodlands begin to increase at ~1211AD reaching a maximum between ~1500-~1600AD. Termination of the last major drought in our record coincides with that of major drought events elsewhere in the West (Stine, 1994; Cook et al, 2004), and marks the beginning of gradual, fluctuating increases in precipitation and in coastal southern California mesic, oak-dominated communities. Offshore, diatom, oxygen isotopes, and planktonic foraminifera data imply cold spring and warm winter sea surface temperatures during the Medieval Climate Anomaly (MCA) that reverse in the Little Ice Age (LIA). These major climate-driven changes in southern California and Santa Barbara Basin are consistent with changes in northern hemisphere circulation, i.e., weakened Arctic Lows, strengthened North Pacific Highs and extended La Niña-like conditions during the MCA and strengthened Aleutian Lows, weakened and westward North Pacific Highs and extended El Niño-like atmospheric conditions during the LIA.

  13. Special Features of the Mechanical Characteristics of Al-Al2O3 Composites Produced By Explosive Compaction of Powders Under Shock-Wave Deformation

    NASA Astrophysics Data System (ADS)

    Zhukov, I. A.; Garkushin, G. V.; Vorozhtsov, S. A.; Khrustalyov, A. P.; Razorenov, S. V.; Kvetinskaya, A. V.; Promakhov, V. V.; Zhukov, A. S.

    2016-01-01

    The results obtained from investigations into the special features inherent in the mechanical characteristics (Hugoniot elastic limit and spall strength) observed under shock-wave loading of Al-Al2O3 composite samples produced by an explosive powder compaction technique are presented. Embedding 10 wt.% of aluminum oxide in the aluminum matrix has been found to increase the Hugoniot elastic limit as opposed to the commercialgrade AD1(Al 1013) aluminum alloy.

  14. 3D τ RR -minimization in AdS4 gauged supergravity

    NASA Astrophysics Data System (ADS)

    Amariti, Antonio; Gnecchi, Alessandra

    2016-07-01

    In this paper we propose the identification in AdS4 N = 2 gauged supergravity of the coefficient τRR of 3D N = 2 SCFTs. We constrain the structure of this function in supergravity by combining the results from unitarity, holography and localization. We show that our conjectured function is minimized by the exact R-charge, corresponding to a gravitational attractor for the scalars of special geometry. We identify this mechanism with the supergravity dual of τ RR -minimization. We check this proposal in ABJM model, comparing with expectations from localization and AdS/CFT duality. We comment also on possible relations with black hole microstates counting, recently obtained from application of localization techniques.

  15. Non-minimally coupled pseudoscalars in AdS4 for instantons in CFT3

    NASA Astrophysics Data System (ADS)

    Naghdi, M.

    2016-06-01

    For the 11-dimensional supergravity over {{{AdS}}}4× {{{S}}}7/{Z}k, beginning with a general four-form ansatz and the main geometry unchanged, we get a tower of massive and tachyonic pseudoscalars. Indeed, the resultant equations can be assigned to the so-called {φ }4 actions of the non-minimally coupled scalar-tensor theories with a cosmological constant. We focus on a well-known tachyonic and a new massive bulk mode, which are singlet under the internal group and break all supersymmetries, associated with skew-whiffing and Wick-rotating of the background four-form flux, respectively. The first one is the conformally coupled {m}2=-2 pseudoscalar in the bulk of Euclidean AdS4, where an exact instanton solution is found and a marginally triple-trace deformation with a proper dimension-1 operator produces an agreeing boundary solution with finite action. From the action evaluated on the solution, we estimate the decay rate of the vacuum tunneling mediated by the instanton. Another massive {m}2=+4 mode, with the so-called non-minimal coupling parameter ξ =-1/3, also breaks the conformal invariance and so there is no exact solution. Then, based on the AdS4/CFT3 correspondence rules, we propose the dimension-4 ({{{Δ }}}+=+4) boundary operator in the skew-whiffed (anti-M2-branes) theory with which to deform the boundary action—consisting of a singlet fermion, an original scalar and U(1) gauges fields—and find some solutions to be matched with the bulk solutions.

  16. Art as an Evolutionary Adaptation: Inspiration from the Visible Supernovae of AD 1054 and AD 3054

    NASA Astrophysics Data System (ADS)

    Corbally, C. J.; Rappaport, M. B.

    2016-01-01

    The authors, an astronomer/priest and an anthropologist/biologist, describe their use of the dramatic arts at the INSAP VIII meeting in their performance of two short skits on the sighting of a supernova in AD 1054 (creating the beautiful Crab Nebula) and a future “Rho Cas” stellar explosion in the constellation Cassiopeia, in AD 3054. They speculate on the emergence of science, religion, and art as bona fide adaptations, responding to natural selection, which served early hominins well in their struggle for existence. They draw parallels to the continued functions of science, religion, and art in modern society.

  17. - criticality of AdS black hole in the Einstein-Maxwell-power-Yang-Mills gravity

    NASA Astrophysics Data System (ADS)

    Zhang, Ming; Yang, Zhan-Ying; Zou, De-Cheng; Xu, Wei; Yue, Rui-Hong

    2015-02-01

    We study the - critical behaivor of N-dimensional AdS black holes in Einstein-Maxwell-power-Yang-Mills gravity. Our results show the existence of the Van der Waals like small-large black hole phase transitions when taking some special values of charges of the Maxwell and Yang-Mills fields. Further to calculate the critical exponents of the black holes at the critical point, we find that they are the same as those in the Van der Waals liquid-gas system.

  18. Phantom Accretion onto the Schwarzschild AdS Black Hole with Topological Defect

    NASA Astrophysics Data System (ADS)

    Amani, Ali R.; Farahani, H.

    2012-09-01

    In this paper, we have studied phantom energy accretion of prefect fluid onto the Schwarzschild AdS black hole with topological defect. We have obtained critical point during the accretion of fluid on the black hole where the speed of flow is equal speed of sound (Sharif and Abbas in Phantom accretion onto the Schwarzschild de-Sitter black hole, 2011, arXiv:1109.1043 [gr-qc]). The critical velocities have been computed so that the speed of fluid into the black hole is less than speed of sound. Finally, we have found that the critical point is near the black hole horizon.

  19. Vinasse added to the concentrate for fattening lambs: intake, animal performance, and carcass and meat characteristics.

    PubMed

    López-Campos, Ó; Bodas, R; Prieto, N; Frutos, P; Andrés, S; Giráldez, F J

    2011-04-01

    Twenty-four Merino lambs (mean BW 15.4 ± 0.13 kg, 6 to 7 wk old) were used to study the effects of the addition of 0 (control), 100 (V10), and 200 (V20) g of vinasse per kilgram of concentrate on intake, animal performance, biochemical blood profile, and carcass and meat characteristics. Lambs were assigned to 1 of 3 experimental diets and fed barley straw and the corresponding concentrate ad libitum. When the animals reached 25 kg of BW, a sample of blood was taken and the lambs were slaughtered. Feed intake, growth rate, biochemical blood profile, and carcass and meat characteristics were assessed. Lambs that received the concentrates with vinasse showed a reduced concentrate intake (linear contrast, P = 0.029) and ADG (linear contrast, P = 0.004) and an increased length of fattening period (linear contrast, P = 0.002) as well as feed:gain ratio (linear contrast P = 0.011). Vinasse enhanced ruminal pH (orthogonal contrast control vs. V10 + V20; P = 0.007). Plasma glucose concentrations declined in lambs fed vinasse (linear contrast, P = 0.003), whereas plasma urea concentration increased in animals fed vinasse (linear contrast, P = 0.036). The plasma concentrations of creatinine, triglycerides, and lactate and the enzyme profile studied (alkaline phosphate, alanine transaminase, glutamate oxal-acetate transaminase, γ-glutamyl transpeptidase, and lactate dehydrogenase) were not modified in response to vinasse inclusion. Lambs in the vinasse groups had less Na(+) and nitrate and greater K(+) and nitrite plasma concentrations (linear contrasts, P < 0.05). None of the carcass characteristics studied was affected by vinasse (P > 0.10). Meat chemical composition and characteristics were unaffected (P > 0.10), but shear force was greater for lambs that received vinasse (orthogonal contrast, control vs. V10 + V20, P = 0.007). The addition of 100 or 200 g vinasse/kg of concentrate for fattening lambs reduced feed intake and growth rate and increased the feed:gain ratio

  20. B Removal by Zr Addition in Electromagnetic Solidification Refinement of Si with Si-Al Melt

    NASA Astrophysics Data System (ADS)

    Lei, Yun; Ma, Wenhui; Sun, Luen; Dai, Yongnian; Morita, Kazuki

    2016-02-01

    This study investigated a new process of enhancing B removal by adding small amounts of Zr in the electromagnetic solidification refinement of Si with Si-Al melt. B in Si was removed by as much as 97.2 pct by adding less than 1057 ppma Zr, and the added Zr was removed by as much as 99.7 pct. In addition, Zr is more effective in enhancing B removal than Ti in the same electromagnetic solidification refining process.

  1. Scientific Publishing: Adding Value, Delivering Impact

    NASA Astrophysics Data System (ADS)

    Mayes, Beth

    2015-08-01

    Publishers are developing new services and applying new technologies to improve publication and reading experiences for the scholarly community. This needs to be implemented with care to avoid adding technology-driven complexity. Our publishing processes need to be widely accessible to both authors and readers and to maintain the scientific record. Beth Mayes will outline new developments at IOP Publishing delivering (1) improvements to the presentation of articles and their commitment to formats that go beyond the PDF, improving the understanding of research. (2) How IOP Publishing is responding to the growing calls for metadata and linking that involve being central to the shared information ecosystem for astronomy. (3) After publication, discuss how publishers invest in metrics and new initiatives for discovery that improve the impact of published research.

  2. Accelerator development in India for ADS programme

    NASA Astrophysics Data System (ADS)

    Singh, P.; Rao, S. V. L. S.; Pande, Rajni; Basak, T.; Roy, Shweta; Aslam, M.; Jain, P.; Srivastava, S. C. L.; Kumar, Rajesh; Nema, P. K.; Kailas, S.; Sahni, V. C.

    2007-02-01

    At BARC, development of a Low Energy High Intensity Proton Accelerator (LEHIPA), as front-end injector of the 1 GeV accelerator for the ADS programme, has been initiated. The major components of LEHIPA (20 MeV, 30 mA) are a 50 keV ECR ion source, a 3 MeV Radio Frequency Quadrupole (RFQ) and a 20 MeV drift tube linac (DTL). The Low Energy Beam Transport (LEBT) and Medium Energy Beam Transport (MEBT) lines match the beam from the ion source to RFQ and from RFQ to DTL respectively. Design of these systems has been completed and fabrication of their prototypes has started. Physics studies of the 20-1000 MeV part of the Linac are also in progress. In this paper, the present status of this project is presented.

  3. Worm epidemics in wireless ad hoc networks

    NASA Astrophysics Data System (ADS)

    Nekovee, Maziar

    2007-06-01

    A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet.

  4. Adding crumb rubber into exterior wall materials.

    PubMed

    Zhu, Han; Thong-On, Norasit; Zhang, Xiong

    2002-10-01

    In Arizona US, most houses are built with walls covered by stuccos/coatings/mortars. This paper presents an explorative investigation of adding crumb rubber into stuccos/coatings/mortars. A series of experiments are conducted to examine the thermal and mechanical performance of the crumb rubber mixes. The results show that, the mixes with crumb rubber do exhibit more desirable performances like being high in crack-resistance and thermal insulation, and low in thermal expansion/contraction. The drawback for the crumb rubber mixes is the reduction in compressive strength, but which can be compensated by other means. As a site experiment, an area of 100 square-feet of crumb rubber coatings for two mix designs is sprayed on a tire-adobe wall. After being sprayed more than 14 months, the coatings apparently are in good condition. Significance of this study is that this practice, if accepted, will yield improved products that consume large quantities of crumb rubber.

  5. Impact of AD995 alumina rods

    SciTech Connect

    Chhabildas, L.C.; Furnish, M.D.; Reinhart, W.D.; Grady, D.E.

    1997-10-01

    Gas guns and velocity interferometric techniques have been used to determine the loading behavior of an AD995 alumina rod 19 mm in diameter by 75 mm and 150 mm long, respectively. Graded-density materials were used to impact both bare and sleeved alumina rods while the velocity interferometer was used to monitor the axial-velocity of the free end of the rods. Results of these experiments demonstrate that (1) a time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod, and (2) the intermediate loading rates obtained in this configuration lie between split Hopkinson bar and shock-loading techniques.

  6. Adding a lens Improves spinning speed characterization.

    PubMed

    Mihaliuk, Eugene; Gullion, Terry

    2015-11-01

    Highly stable sample rotation is important in many solid-state NMR experiments. Whether the necessary stability is achieved is not always clear. Typically only an average frequency over some time interval (often relatively long and unknown) is available from the spinning speed controller readout, which is not representative of the short-term variations of instantaneous rotation frequency. The necessity of the relatively slow measurement of spinning speed is a consequence of phase noise in the tachometer, which prevents speed measurement to be both rapid and precise at the same time. We show that adding a lens to the tachometer, without any other changes in the probe, reduces phase noise by nearly an order of magnitude and allows improved measurement of the spinning speed.

  7. Droplet Number Concentration Value-Added Product

    SciTech Connect

    Riihimaki, L.; McFarlane, S.; Sivaraman, C.

    2014-06-01

    The ndrop_mfrsr value-added product (VAP) provides an estimate of the cloud droplet number concentration of overcast water clouds retrieved from cloud optical depth from the multi-filter rotating shadowband radiometer (MFRSR) instrument and liquid water path (LWP) retrieved from the microwave radiometer (MWR). When cloud layer information is available from vertically pointing lidar and radars in the Active Remote Sensing of Clouds (ARSCL) product, the VAP also provides estimates of the adiabatic LWP and an adiabatic parameter (beta) that indicates how divergent the LWP is from the adiabatic case. quality control (QC) flags (qc_drop_number_conc), an uncertainty estimate (drop_number_conc_toterr), and a cloud layer type flag (cloud_base_type) are useful indicators of the quality and accuracy of any given value of the retrieval. Examples of these major input and output variables are given in sample plots in section 6.0.

  8. Aerosol Best Estimate Value-Added Product

    SciTech Connect

    Flynn, C; Turner, D; Koontz, A; Chand, D; Sivaraman, C

    2012-07-19

    The objective of the Aerosol Best Estimate (AEROSOLBE) value-added product (VAP) is to provide vertical profiles of aerosol extinction, single scatter albedo, asymmetry parameter, and Angstroem exponents for the atmospheric column above the Central Facility at the ARM Southern Great Plains (SGP) site. We expect that AEROSOLBE will provide nearly continuous estimates of aerosol optical properties under a range of conditions (clear, broken clouds, overcast clouds, etc.). The primary requirement of this VAP was to provide an aerosol data set as continuous as possible in both time and height for the Broadband Heating Rate Profile (BBHRP) VAP in order to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Even though BBHRP has been completed, AEROSOLBE results are very valuable for environmental, atmospheric, and climate research.

  9. Spin Filtering Studies at COSY and AD

    SciTech Connect

    Nass, Alexander

    2009-08-04

    The high physics potential of experiments with stored high-energy polarized antiprotons led to the proposal of PAX (Polarized Antiproton eXperiment) for the High Energy Storage Ring (HESR) of the FAIR at GSI (Darmstadt/Germany). It is proposed to polarize a stored antiproton beam by means of spin filtering with a polarized H (D) gas target. The feasibility of spin filtering has been demonstrated in the FILTEX experiment. The current interpretation foresees a self-cancellation of the electron contribution to the filtering process and only the hadronic contribution is effective. Several experimental studies with protons (at COSY/Juelich) as well as antiprotons (at AD/CERN) will be carried out to test the principle and measure p-barp-vector and p-bard-vector cross sections. A polarized internal gas target (PIT) with surrounding Silicon detectors immersed into a low-beta section has to be set up.

  10. AdS flowing black funnels: stationary AdS black holes with non-Killing horizons and heat transport in the dual CFT

    NASA Astrophysics Data System (ADS)

    Fischetti, Sebastian; Marolf, Donald; Santos, Jorge E.

    2013-04-01

    We construct stationary non-equilibrium black funnels locally asymptotic to global AdS4 in vacuum Einstein-Hilbert gravity with a negative cosmological constant. These are non-compactly-generated black holes in which a single connected bulk horizon extends to meet the conformal boundary. Thus the induced (conformal) boundary metric has smooth horizons as well. In our examples, the boundary spacetime contains a pair of black holes connected through the bulk by a tubular bulk horizon. Taking one boundary black hole to be hotter than the other (ΔT ≠ 0) prohibits equilibrium. The result is a so-called flowing funnel, a stationary bulk black hole with a non-Killing horizon that may be said to transport heat toward the cooler boundary black hole. While generators of the bulk future horizon evolve toward zero expansion in the far future, they begin at finite affine parameter with infinite expansion on a singular past horizon characterized by power-law divergences with universal exponents. We explore both the horizon generators and the boundary stress tensor in detail. While most of our results are numerical, a semi-analytic fluid/gravity description can be obtained by passing to a one-parameter generalization of the above boundary conditions. The new parameter detunes the temperatures Tbulk BH and Tbndy BH of the bulk and boundary black holes, and we may then take α = {T_{bndy \\ BH}/{T_{bulk \\ BH}} and ΔT small to control the accuracy of the fluid-gravity approximation. In the small α, ΔT regime, we find excellent agreement with our numerical solutions. For our cases the agreement also remains quite good even for α ˜ 0.8. In terms of a dual CFT, our α = 1 solutions describe heat transport via a large N version of Hawking radiation through a deconfined plasma that couples efficiently to both boundary black holes.

  11. Rabies in medieval Persian literature – the Canon of Avicenna (980–1037 AD)

    PubMed Central

    2014-01-01

    Ibn Sina (980–1037 AD), known by his full name Abu Ali al-Hussain ibn Abdallah ibn Sina and the Latin name ‘Avicenna’, was a Persian scholar who is primarily remembered for his contributions to the science of medicine. He authored Al-Qanun fi al-Tibb (The Canon of Medicine). Sections of his work are devoted to detailed descriptions of a number of infectious illnesses, particularly rabies. Avicenna described rabies in humans and animals and explained its clinical manifestations, route of transmission, and treatment methods. In this article, our goal is to discuss Avicenna’s 11th-century points of view on rabies and compare them with modern medical knowledge. PMID:24533686

  12. Cloud Condensation Nuclei Profile Value-Added Product

    SciTech Connect

    McFarlane, S; Sivaraman, C; Ghan, S

    2012-10-08

    The cloud condensation nuclei (CCN) concentration at cloud base is the most relevant measure of the aerosol that influences droplet formation in clouds. Since the CCN concentration depends on supersaturation, a more general measure of the CCN concentration is the CCN spectrum (values at multiple supersaturations). The CCN spectrum is now measured at the surface at several fixed ARM sites and by the ARM Mobile Facility (AMF), but is not measured at the cloud base. Rather than rely on expensive aircraft measurements for all studies of aerosol effects on clouds, a way to project CCN measurements at the surface to cloud base is needed. Remote sensing of aerosol extinction provides information about the vertical profile of the aerosol, but cannot be directly related to the CCN concentration because the aerosol extinction is strongly influenced by humidification, particularly near cloud base. Ghan and Collins (2004) and Ghan et al. (2006) propose a method to remove the influence of humidification from the extinction profiles and tie the “dry extinction” retrieval to the surface CCN concentration, thus estimating the CCN profile. This methodology has been implemented as the CCN Profile (CCNPROF) value-added product (VAP).

  13. Formation of Small Blocky Al3Ti Particles via Direct Reaction Between Solid Ti Powders and Liquid Al

    NASA Astrophysics Data System (ADS)

    Liu, Z. W.; Han, Q.; Li, J. G.

    2012-12-01

    The evolution of titanium powders in the pure aluminum melt at a lower temperature was studied in our research. The process involved some titanium powders being added into the pure aluminum melt at 1003 K (730 °C), and then the melt was cast into an ingot after 5 minutes. A reaction layer composed of some loose Al3Ti particles was formed on the solid Ti surface due to the reactive diffusion between titanium and aluminum. In-situ blocky Al3Ti particles smaller than 5 μm were produced in the aluminum matrix. A reaction-peeling model was suggested to illustrate the formation mechanism of Al3Ti particles, and a simple approach for fabricating in-situ Al3Ti/Al-alloy composites was proposed as well.

  14. Abd al-Rahman al-Sufi and his book of the fixed stars: a journey of re-discovery

    NASA Astrophysics Data System (ADS)

    Hafez, Ihsan

    2010-10-01

    Al-Şūfı's Book of the Fixed Stars, dating from around AD 964, is one of the most important medieval Arabic treatises on astronomy. This major work contains an extensive star catalog, which lists star co-ordinates and magnitude estimates, as well as detailed star charts. Other topics include descriptions of nebulae, colors of stars and Arabic folk astronomy. Al-Şūfı's book was based on Ptolemy's classical work called the Almagest which was written around A.D. 137. Al-Şūfı updated Ptolemy's stellar longitudes from A.D. 137 to 964 by adding 12 degrees and 42 minutes on Ptolemy's longitude values to allow for precession. However, it is surprising that at present no English translation of al-Şūfı's treatise exists. Therefore this is a Doctorate thesis which includes for the first time a complete English translation of the main parts of al-Şūfı's work as well as a detailed study of this important book. The main topics which have been discussed in this study include a brief biography on al-Şūfı, the extant manuscripts of al-Şūfı's treatise, the structure of the book and star catalogue, and the star maps and charts. One of al-Şūfı's innovations in charting the stars was the production of dual illustrations for each of Ptolemy's constellations. One illustration was as portrayed on a celestial globe. The other illustration was as viewed directly in the night sky. Al-Şūfı's contribution to astronomy was not only limited to writing this book but he was also instrumental in developing the science of astronomy for a very long time. He also contributed to the building of an important observatory in the city of Shiraz as well as constructing many astronomical instruments such as astrolabes and celestial globes. His influence reverberated throughout history reaching as far as the end of the 19th century. This study also includes a major finding which is al-Şūfı's magnitude unique 3-step intermediate magnitude system. Al-Şūfı identified more than one

  15. Baldcypress tree ring elemental concentrations at Reelfoot Lake, Tennessee from AD 1795 to AD 1820

    SciTech Connect

    Van Arsdale, R.; Hall, G.

    1995-11-01

    Many two hundred year old baldcypress trees in Reelfoot Lake, Tennessee, lived through the great New Madrid earthquakes of 1811--1812. This study was undertaken to determine if the elemental composition of baldcypress tree rings showed any systematic variation through the earthquake period of AD 1795 through AD 1820. Multiple cores were collected from two Reelfoot Lake baldcypress trees and analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Individual yearly rings and five-year ring segments were analyzed to determine their elemental compositions. The cores were analyzed for Li through U but only Ba, Ce, Cs, Cu, I, La, Mg, Mn, Nd, Rb, Sm, Sr, and Zn were found to be in appropriate concentrations for this study. Of these elements only Ce, I, La, Nd, Rb, and Sm showed any systematic changes within individual cores. Comparison of three cores taken from one tree reveal that tree-ring elemental concentrations and changes in tree-ring elemental concentration through time are very different among the cores. When comparing the elemental concentrations of tree rings for the same years in the two different trees neither elemental concentrations nor changes in elemental concentration through time were similar. We conclude that the elemental concentrations in the tree rings of the two baldcypress trees analyzed in this study show no systematic change through the earthquake period of AD 1795 through AD 1820.

  16. Exact results for the low energy AdS 4 × 3 string theory

    NASA Astrophysics Data System (ADS)

    Fabbri, Alessandro; Fioravanti, Davide; Piscaglia, Simone; Tateo, Roberto

    2013-11-01

    We derive the Thermodynamic Bethe Ansatz equations for the relativistic sigma model describing the AdS 4 × 3 string II A theory at strong coupling (i.e. in the Alday-Maldacena decoupling limit). The corresponding Y -system involves an infinite number of Y functions and is of a new type, although it shares a peculiar feature with the Y -system for AdS 4 × 3. A truncation of the equations at level p and a further generalisation to generic rank N allow us an alternative description of the theory as the N =4, p = ∞ representative in an infinite family of models corresponding to the conformal cosets ( N -1) p × U(1), perturbed by a relevant composite field ϕ ( N,p) = ϕ[( N -1) p ] × ϕ [U(1)] that couples the two independent conformal field theories. The calculation of the ultraviolet central charge confirms the conjecture by Basso and Rej and the conformal dimension of the perturbing operator, at every N and p, is obtained using the Y-system periodicity. The conformal dimension of ϕ[( N -1) p ] matches that of the field identified by Fendley while discussing integrability issues for the purely bosonic N -1 sigma model.

  17. Quantum compositeness of gravity: black holes, AdS and inflation

    SciTech Connect

    Dvali, Gia; Gomez, Cesar E-mail: cesar.gomez@uam.es

    2014-01-01

    Gravitational backgrounds, such as black holes, AdS, de Sitter and inflationary universes, should be viewed as composite of N soft constituent gravitons. It then follows that such systems are close to quantum criticality of graviton Bose-gas to Bose-liquid transition. Generic properties of the ordinary metric description, including geodesic motion or particle-creation in the background metric, emerge as the large-N limit of quantum scattering of constituent longitudinal gravitons. We show that this picture correctly accounts for physics of large and small black holes in AdS, as well as reproduces well-known inflationary predictions for cosmological parameters. However, it anticipates new effects not captured by the standard semi-classical treatment. In particular, we predict observable corrections that are sensitive to the inflationary history way beyond last 60 e-foldings. We derive an absolute upper bound on the number of e-foldings, beyond which neither de Sitter nor inflationary Universe can be approximated by a semi-classical metric. However, they could in principle persist in a new type of quantum eternity state. We discuss implications of this phenomenon for the cosmological constant problem.

  18. Quantum compositeness of gravity: black holes, AdS and inflation

    SciTech Connect

    Dvali, Gia; Gomez, Cesar

    2014-01-14

    Gravitational backgrounds, such as black holes, AdS, de Sitter and inflationary universes, should be viewed as composite of N soft constituent gravitons. It then follows that such systems are close to quantum criticality of graviton Bose-gas to Bose-liquid transition. Generic properties of the ordinary metric description, including geodesic motion or particle-creation in the background metric, emerge as the large-N limit of quantum scattering of constituent longitudinal gravitons. We show that this picture correctly accounts for physics of large and small black holes in AdS, as well as reproduces well-known inflationary predictions for cosmological parameters. However, it anticipates new effects not captured by the standard semi-classical treatment. In particular, we predict observable corrections that are sensitive to the inflationary history way beyond last 60 e-foldings. We derive an absolute upper bound on the number of e-foldings, beyond which neither de Sitter nor inflationary Universe can be approximated by a semi-classical metric. However, they could in principle persist in a new type of quantum eternity state. We discuss implications of this phenomenon for the cosmological constant problem.

  19. Quartic AdS interactions in higher-spin gravity from Conformal Field Theory

    NASA Astrophysics Data System (ADS)

    Bekaert, X.; Erdmenger, J.; Ponomarev, D.; Sleight, C.

    2015-11-01

    Clarifying the locality properties of higher-spin gravity is a pressing task, but notoriously difficult due to the absence of a weakly-coupled flat regime. The simplest non-trivial case where this question can be addressed is the quartic self-interaction of the AdS scalar field present in the higher-spin multiplet. We investigate this issue in the context of the holographic duality between the minimal bosonic higher-spin theory on AdS4 and the free O( N) vector model in three dimensions. In particular, we determine the exact explicit form of the derivative expansion of the bulk scalar quartic vertex. The quartic vertex is obtained from the field theory four-point function of the operator dual to the bulk scalar, by making use of our previous results for the Witten diagrams of higher-spin exchanges. This is facilitated by establishing the conformal block expansions of both the boundary four-point function and the dual bulk Witten diagram amplitudes. We show that the vertex we find satisfies a generalised notion of locality.

  20. Supersymmetric AdS 3 × S 2 M-theory geometries with fluxes

    NASA Astrophysics Data System (ADS)

    Colgáin, Eoin Ó; Wu, Jun-Bao; Yavartanoo, Hossein

    2010-08-01

    Motivated by a recent observation that the LLM geometries admit 1/4-BPS M5-brane probes with worldvolume AdS 3 × Σ2 × S 1 preserving the R-symmetry, SU(2) × U(1), we initiate a classification of the most general AdS 3× S 2 geometries in M-theory dual to two-dimensional chiral mathcal{N} = left( {4,0} right) SCFTs. We retain all field strengths consistent with symmetry and derive the torsion conditions for the internal six-manifold, M 6, in terms of two linearly independent spinors. Surprisingly, we identify three Killing directions for M 6, but only two of these generate isometries of the overall ansatz. We show that the existence of this third direction depends on the norm of the spinors. With the torsion conditions derived, we establish the MSW solution as the only solution in the class where M6 is an SU(3)-structure manifold. Then, specialising to the case where the spinors define an SU(2)-structure, we note that supersymmetry dictates that all magnetic fluxes necessarily thread the S 2. Finally, by assuming that the two remaining Killing directions are parallel and aligned with one of the two vectors defining the SU(2)-structure, we derive a general relationship for the two spinors before extracting a known class of solutions from the torsion conditions.

  1. Null-polygonal minimal surfaces in AdS4 from perturbed W minimal models

    NASA Astrophysics Data System (ADS)

    Hatsuda, Yasuyuki; Ito, Katsushi; Satoh, Yuji

    2013-02-01

    We study the null-polygonal minimal surfaces in AdS4, which correspond to the gluon scattering amplitudes/Wilson loops in {N} = 4 super Yang-Mills theory at strong coupling. The area of the minimal surfaces with n cusps is characterized by the thermodynamic Bethe ansatz (TBA) integral equations or the Y-system of the homogeneous sine-Gordon model, which is regarded as the SU( n - 4)4 /U(1) n-5 generalized parafermion theory perturbed by the weight-zero adjoint operators. Based on the relation to the TBA systems of the perturbed W minimal models, we solve the TBA equations by using the conformal perturbation theory, and obtain the analytic expansion of the remainder function around the UV/regular-polygonal limit for n = 6 and 7. We compare the rescaled remainder function for n = 6 with the two-loop one, to observe that they are close to each other similarly to the AdS3 case.

  2. Quasinormal modes and holographic correlators in a crunching AdS geometry

    NASA Astrophysics Data System (ADS)

    Kumar, S. Prem; Vaganov, Vladislav

    2016-02-01

    We calculate frequency space holographic correlators in an asymptotically AdS crunching background, dual to a relevant deformation of the M2-brane CFT placed in de Sitter spacetime. For massless bulk scalars, exploiting the connection to a solvable supersymmetric quantum mechanical problem, we obtain the exact frequency space correlator for the dual operator in the deformed CFT. Controlling the shape of the crunching surface in the Penrose diagram by smoothly dialling the deformation from zero to infinity, we observe that in the large deformation limit the Penrose diagram becomes a `square', and the exact holographic correlators display striking similarities to their counterparts in the BTZ black hole and its higher dimensional generalisations. We numerically determine quasinormal poles for relevant and irrelevant operators, and find an intricate pattern of these in the complex frequency plane. In the case of relevant operators, the deformation parameter has an infinite sequence of critical values, each one characterised by a pair of poles colliding and moving away from the imaginary frequency axis with increasing deformation. In the limit of infinite deformation all scalar operators have identical quasinormal spectra. We compare and contrast our strongly coupled de Sitter QFT results with strongly coupled thermal correlators from AdS black holes.

  3. Secret symmetries of type IIB superstring theory on Ad{{S}_{3}} × {{S}^{3}} × {{M}^{4}}

    NASA Astrophysics Data System (ADS)

    Pittelli, Antonio; Torrielli, Alessandro; Wolf, Martin

    2014-11-01

    We establish features of so-called Yangian secret symmetries for AdS3 type IIB superstring backgrounds, thus verifying the persistence of such symmetries to this new instance of the AdS/CFT correspondence. Specifically, we find two a priori different classes of secret symmetry generators. One class of generators, anticipated from the previous literature, is more naturally embedded in the algebra governing the integrable scattering problem. The other class of generators is more elusive and somewhat closer in its form to its higher-dimensional AdS5 counterpart. All of these symmetries respect left-right crossing. In addition, by considering the interplay between left and right representations, we gain a new perspective on the AdS5 case. We also study the RTT-realisation of the Yangian in AdS3 backgrounds, thus establishing a new incarnation of the Beisert-de Leeuw construction.

  4. ALS superbend magnet system

    SciTech Connect

    Zbasnik, J.; Wang, S.T.; Chen, J.Y.; DeVries, G.J.; DeMarco, R.; Fahmie, M.; Geyer, A.; Green, M.A.; Harkins, J.; Henderson, T.; Hinkson, J.; Hoyer, E.H.; Krupnick, J.; Marks, S.; Ottens, F.; Paterson, J.A.; Pipersky, P.; Portmann, G.; Robin, D.A.; Schlueter, R.D.; Steier, C.; Taylor, C.E.; Wahrer, R.

    2000-09-15

    The Lawrence Berkeley National Laboratory is preparing to upgrade the Advanced Light Source (ALS) with three superconducting dipoles (Superbends). In this paper we present the final magnet system design which incorporates R&D test results and addresses the ALS operational concerns of alignment, availability, and economy. The design incorporates conduction-cooled Nb-Ti windings and HTS current leads, epoxy-glass suspension straps, and a Gifford-McMahon cryocooler to supply steady state refrigeration. We also present the current status of fabrication and testing.

  5. Modulus measurements in ordered Co-Al, Fe-Al, and Ni-Al alloys

    NASA Technical Reports Server (NTRS)

    Harmouche, M. R.; Wolfenden, A.

    1985-01-01

    The composition and/or temperature dependence of the dynamic Young's modulus for the ordered B2 Co-Al, Fe-Al, and Ni-Al aluminides has been investigated using the piezoelectric ultrasonic composite oscillator technique (PUCOT). The modulus has been measured in the composition interval 48.49 to 52.58 at. pct Co, 50.87 to 60.2 at. pct Fe, and 49.22 to 55.95 at. pct Ni for Co-Al, Fe-Al, and Ni-Al, respectively. The measured values for Co-Al are in the temperature interval 300 to 1300 K, while those for the other systems are for ambient temperature only. The data points show that Co-Al is stiffer than Fe-Al, which is stiffer than Ni-Al. The data points for Fe-Al and Ni-Al are slightly higher than those reported in the literature.

  6. RG flow and thermodynamics of causal horizons in higher-derivative AdS gravity

    NASA Astrophysics Data System (ADS)

    Banerjee, Shamik; Bhattacharyya, Arpan

    2016-05-01

    In arXiv:1508.01343 [hep-th], one of the authors proposed that in AdS/CFT the gravity dual of the boundary c-theorem is the second law of thermodynamics satisfied by causal horizons in AdS and this was verified for Einstein gravity in the bulk. In this paper we verify this for higher derivative theories. We pick up theories for which an entropy expression satisfying the second law exists and show that the entropy density evaluated on the causal horizon in a RG flow geometry is a holographic c-function. We also prove that given a theory of gravity described by a local covariant action in the bulk a sufficient condition to ensure holographic c-theorem is that the second law of causal horizon thermodynamics be satisfied by the theory. This allows us to explicitly construct holographic c-function in a theory where there is curvature coupling between gravity and matter and standard null energy condition cannot be defined although second law is known to hold. Based on the duality between c-theorem and the second law of causal horizon thermodynamics proposed in arXiv:1508.01343 [hep-th] and the supporting calculations of this paper we conjecture that every Unitary higher derivative theory of gravity in AdS satisfies the second law of causal horizon thermodynamics. If this is not true then c-theorem will be violated in a unitary Lorentz invariant field theory.

  7. Impact of adding nitrate or increasing the lipid content of two contrasting diets on blood methaemoglobin and performance of two breeds of finishing beef steers.

    PubMed

    Duthie, C-A; Rooke, J A; Troy, S; Hyslop, J J; Ross, D W; Waterhouse, A; Roehe, R

    2016-05-01

    Adding nitrate to the diet or increasing the concentration of dietary lipid are effective strategies for reducing enteric methane emissions. This study investigated their effect on health and performance of finishing beef cattle. The experiment was a two×two×three factorial design comprising two breeds (CHX, crossbred Charolais; LU, Luing); two basal diets consisting of (g/kg dry matter (DM), forage to concentrate ratios) 520 : 480 (Mixed) or 84 : 916 (Concentrate); and three treatments: (i) control with rapeseed meal as the main protein source replaced with either (ii) calcium nitrate (18 g nitrate/kg diet DM) or (iii) rapeseed cake (RSC, increasing acid hydrolysed ether extract from 25 to 48 g/kg diet DM). Steers (n=84) were allocated to each of the six basal diet×treatments in equal numbers of each breed with feed offered ad libitum. Blood methaemoglobin (MetHb) concentrations (marker for nitrate poisoning) were monitored throughout the study in steers receiving nitrate. After dietary adaptation over 28 days, individual animal intake, performance and feed efficiency were recorded for a test period of 56 days. Blood MetHb concentrations were low and similar up to 14 g nitrate/kg diet DM but increased when nitrate increased to 18 g nitrate/kg diet DM (P0.05). Neither basal diet nor treatment affected carcass quality (P>0.05), but CHX steers achieved a greater killing out proportion (P<0.001) than LU steers. Thus, adding nitrate to the diet or increasing the level of dietary lipid through the use of cold-pressed RSC, did not adversely affect health or performance of finishing beef steers when used within the diets studied. PMID:26627142

  8. Full vector archaeomagnetic data and Bayesian modelling for 1300 to 1750 AD

    NASA Astrophysics Data System (ADS)

    Schnepp, E.; Lanos, P.; Chauvin, A.

    2009-04-01

    The data base of geomagnetic palaeointensities obtained from archaeological artefacts is poor and very scattered for Western and Central Europe. High precision palaeointensities have been determined from a single archaeological site in Lübeck (Germany) where a sequence of 25 bread-oven-floors has been preserved in a bakery from medieval times until today. Age dating confines the time interval from about 1300 AD to about 1750 AD. Palaeomagnetic directions have been determined from each oven-floor (Schnepp et al., JGR, 2003). Palaeointensity was measured from selected specimens with the double-heating Thellier method and reliable palaeointensity results have been obtained. Tests for thermoremanent magnetisation anisotropy have been performed, but did not show a significant change, while a cooling rate correction was not necessary. 22 mean palaeointensity values derived from the oven-floors show maxima in the 15th and early 17th century AD, followed by a decrease of palaeointensity of about 25% until 1750 AD. The Thellier experiments provided also new characteristic remanent magnetisation directions which were included in the data set. Mean directions have been recalculated. Palaeointensity together with the directions represent a record of about 450 years full vector secular variation. From this full vector data set a secular variation curve has been calculated using a Bayesian modelling taking dating errors, all errors on the field vector and stratigraphy into account. A smooth curve with an error envelope was obtained which compares very well with the gufm1 geomagnetic model (Jackson et al., Phil. Trans. R. Soc. Lond. A, 2000) obtained from historical observations starting at 1600 AD. Comparison of the marginal curve obtained for palaeointensity with a selected data set of archaeomagnetic intensities from Western and Central Europe will be discussed.

  9. Al Shanker Remembers.

    ERIC Educational Resources Information Center

    American Educator, 2000

    2000-01-01

    In a 1996 interview shortly before his death, Al Shanker, longtime president of the American Federation of Teachers, discussed such topics as: his own educational experiences; how he learned about political fighting in the Boy Scouts; the appeal of socialism; multinational corporations and the nation state; teaching tough students; and John Dewey…

  10. Fosetyl-al

    Integrated Risk Information System (IRIS)

    Fosetyl - al ; CASRN 39148 - 24 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  11. ALS renewal moves forward

    NASA Astrophysics Data System (ADS)

    Falcone, R. W.; Feinberg, B.; Hussain, Z.; Kirz, J.; Krebs, G. F.; Padmore, H. A.; Robin, D. S.; Robinson, A. L.

    2007-11-01

    As the result of an extensive long-term planning process involving all its stakeholders—management, staff, and users—the ALS has seen its future and is aggressively moving ahead to implement its vision for keeping the facility at the cutting edge for the next 2-3 decades. The evolving strategic plan now in place aims to renew the ALS so it can address a new generation of fundamental questions about size dependent and dimensional-confinement phenomena at the nanoscale; correlation and complexity in physical, biological, and environmental systems; and temporal evolution, assembly, dynamics and ultrafast phenomena. The renewal spans three areas: (1) increased staffing at beamlines to support the growing user community and safety professionals to keep an increasingly complex facility hazard free; (2) implementing advances in accelerator, insertion device, beamline, and detector technology that will make it possible for ALS users to address emerging grand scientific and technological challenges with incisive world-class tools; and (3) construction of a user support building and guest housing that will increase the safety and user friendliness of the ALS by providing users office, meeting, experiment staging, and laboratory space for their work and on-site accommodations at reasonable rates.

  12. Preferential infection of human Ad5-specific CD4 T cells by HIV in Ad5 naturally exposed and recombinant Ad5-HIV vaccinated individuals.

    PubMed

    Hu, Haitao; Eller, Michael A; Zafar, Shah; Zhou, Yu; Gu, Mengnan; Wei, Zhi; Currier, Jeffrey R; Marovich, Mary A; Kibuuka, Hannah N; Bailer, Robert T; Koup, Richard A; Robb, Merlin L; Michael, Nelson L; Kim, Jerome H; Ratto-Kim, Silvia

    2014-09-16

    Efficacy trials of adenovirus 5-vectored candidate HIV vaccines [recombinant Ad5 (rAd5)-HIV] were halted for futility due to lack of vaccine efficacy and unexpected excess HIV infections in the vaccine recipients. The potential immunologic basis for these observations is unclear. We comparatively evaluated the HIV susceptibility and phenotypes of human CD4 T cells specific to Ad5 and CMV, two viruses that have been used as HIV vaccine vectors. We show that Ad5-specific CD4 T cells, either induced by natural Ad5 exposure or expanded by rAd5 vaccination, are highly susceptible to HIV in vitro and are preferentially lost in HIV-infected individuals compared with CMV-specific CD4 T cells. Further investigation demonstrated that Ad5-specific CD4 T cells selectively display a proinflammatory Th17-like phenotype and express macrophage inflammatory protein 3α and α4β7 integrin, suggestive of gut mucosa homing potential of these cells. Analysis of HIV p24 and cytokine coexpression using flow cytometry revealed preferential infection of IL-17- and IL-2-producing, Ad5-specific CD4 T cells by HIV in vitro. Our data suggest a potential mechanism explaining the excess HIV infections in vaccine recipients after rAd5-HIV vaccination and highlight the importance of testing the HIV susceptibility of vaccine-generated, vector and insert-specific CD4 T cells in future HIV vaccine studies. PMID:25197078

  13. Spontaneous ad hoc mobile cloud computing network.

    PubMed

    Lacuesta, Raquel; Lloret, Jaime; Sendra, Sandra; Peñalver, Lourdes

    2014-01-01

    Cloud computing helps users and companies to share computing resources instead of having local servers or personal devices to handle the applications. Smart devices are becoming one of the main information processing devices. Their computing features are reaching levels that let them create a mobile cloud computing network. But sometimes they are not able to create it and collaborate actively in the cloud because it is difficult for them to build easily a spontaneous network and configure its parameters. For this reason, in this paper, we are going to present the design and deployment of a spontaneous ad hoc mobile cloud computing network. In order to perform it, we have developed a trusted algorithm that is able to manage the activity of the nodes when they join and leave the network. The paper shows the network procedures and classes that have been designed. Our simulation results using Castalia show that our proposal presents a good efficiency and network performance even by using high number of nodes.

  14. Reactive Polyphenols: Adding a Function to DOM

    NASA Astrophysics Data System (ADS)

    Caldwell, B. A.; Lajtha, K.; Frentress, J.; Crow, S. E.

    2006-12-01

    Both the quantity and the quality of DOM changes dramatically as it moves in solution from plant detritus through the terrestrial landscape to rivers. In very N-limited ecosystems, ecosystem theory would suggest that DON would be efficiently retained, and yet DON export can be substantial and may comprise over 90 percent of total N export in many highly limited upland forested ecosystems. We are exploring the hypothesis that DOM contains reactive polyphenols that can bind significant amounts of otherwise highly labile proteinaceous matter and thus play a large role both in N export and the chemistry of DOM delivered to rivers. While polyphenols have been measured across a wide range of aqueous environments, results are usually limited to an estimate of total phenolics, commonly using the Folin-Ciocalteu reagent. We modified this general assay by adding a step where protein-complexing polyphenols are removed from a subsample by shaking with an insoluble protein. Measuring DOM polyphenols with and without the protein-binding step gives estimates of total phenolics and non-protein reactive phenolics. Protein-binding polyphenols are then calculated by difference. Preliminary measurements with soil lysimeter solutions, soil extracts and stream water collected from watersheds in western Oregon show that over 75 percent of the total polyphenols can bind to protein. Determining the protein-binding function of DOM under different climates, soil and vegetation can provide useful insight into the role of DOM into the N cycle and terrestrial-aquatic linkages.

  15. Snacks, sweetened beverages, added sugars, and schools.

    PubMed

    2015-03-01

    Concern over childhood obesity has generated a decade-long reformation of school nutrition policies. Food is available in school in 3 venues: federally sponsored school meal programs; items sold in competition to school meals, such as a la carte, vending machines, and school stores; and foods available in myriad informal settings, including packed meals and snacks, bake sales, fundraisers, sports booster sales, in-class parties, or other school celebrations. High-energy, low-nutrient beverages, in particular, contribute substantial calories, but little nutrient content, to a student's diet. In 2004, the American Academy of Pediatrics recommended that sweetened drinks be replaced in school by water, white and flavored milks, or 100% fruit and vegetable beverages. Since then, school nutrition has undergone a significant transformation. Federal, state, and local regulations and policies, along with alternative products developed by industry, have helped decrease the availability of nutrient-poor foods and beverages in school. However, regular access to foods of high energy and low quality remains a school issue, much of it attributable to students, parents, and staff. Pediatricians, aligning with experts on child nutrition, are in a position to offer a perspective promoting nutrient-rich foods within calorie guidelines to improve those foods brought into or sold in schools. A positive emphasis on nutritional value, variety, appropriate portion, and encouragement for a steady improvement in quality will be a more effective approach for improving nutrition and health than simply advocating for the elimination of added sugars.

  16. Keratinolytic proteinase from Bacillus thuringiensis AD-12.

    PubMed

    Gegeckas, Audrius; Gudiukaitė, Renata; Citavicius, Donaldas

    2014-08-01

    A new isolated strain noted to produce a novel detergent-stable serine keratinolytic proteinase and identified as Bacillus thuringiensis AD-12. Native keratinolytic proteinase from B. thuringiensis (BtKER) was purified and characterized. The purified BtKER enzyme is a monomer with a molecular mass of 39kDa. Biochemical characterization assays revealed that the BtKER attained optimal activity at pH 7 and 30°C. Residual activity after 1h incubation at 50°C was higher than 80%. The enzyme was activated and stabilized by Mn(2+) and Li(+) metal ions but inactivated by organic solvents. Purified BtKER showed the highest substrate specificity toward keratin from wool>sodium caseinate>collagen>BSA>gelatin in descending order. BtKER is the first reported keratinolytic proteinase from B. thuringiensis and obtained results suggested that new characterized enzyme can be a powerful biocatalyst in peptide production associated to hydrolysis of keratinous and/or keratin-like waste.

  17. Snacks, sweetened beverages, added sugars, and schools.

    PubMed

    2015-03-01

    Concern over childhood obesity has generated a decade-long reformation of school nutrition policies. Food is available in school in 3 venues: federally sponsored school meal programs; items sold in competition to school meals, such as a la carte, vending machines, and school stores; and foods available in myriad informal settings, including packed meals and snacks, bake sales, fundraisers, sports booster sales, in-class parties, or other school celebrations. High-energy, low-nutrient beverages, in particular, contribute substantial calories, but little nutrient content, to a student's diet. In 2004, the American Academy of Pediatrics recommended that sweetened drinks be replaced in school by water, white and flavored milks, or 100% fruit and vegetable beverages. Since then, school nutrition has undergone a significant transformation. Federal, state, and local regulations and policies, along with alternative products developed by industry, have helped decrease the availability of nutrient-poor foods and beverages in school. However, regular access to foods of high energy and low quality remains a school issue, much of it attributable to students, parents, and staff. Pediatricians, aligning with experts on child nutrition, are in a position to offer a perspective promoting nutrient-rich foods within calorie guidelines to improve those foods brought into or sold in schools. A positive emphasis on nutritional value, variety, appropriate portion, and encouragement for a steady improvement in quality will be a more effective approach for improving nutrition and health than simply advocating for the elimination of added sugars. PMID:25713277

  18. Determining Positions and Desired Applicant Characteristics in Sports Job Ads

    ERIC Educational Resources Information Center

    Atali, Levent

    2015-01-01

    The purpose of this study is to determine the diversity of positions occurring in sports job ads and reveal the characteristics requested from applicants for each position. This study examined 103 sports-related job ads obtained from four human resources websites. Using content analysis, job ads were examined in terms of job titles, and the…

  19. John Randolph of Roanoke and the "Argumentum Ad Hominem."

    ERIC Educational Resources Information Center

    Geiser, Michael P.

    2000-01-01

    Analyzes John Randolph's use of "ad hominem" arguments, in an excerpt from the Yazoo Claims debate in 1805, in light of Douglas Walton's research into the "ad hominem." Claims the arguments employed by Randolph confirm Walton's contention that the "ad hominem" is not inherently fallacious, but is a defensible form of argument. (NH)

  20. 76 FR 71430 - Automatic Dependent Surveillance Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-17

    ... forum for the U.S. and international aviation community to define a strategy for incorporating ADS-B In... the ADS-B In Aviation Rulemaking Committee, Recommendations to Define a Strategy for Incorporating ADS... request to provide a forum for the U.S. and international aviation community to provide recommendations...

  1. Evaluating Teachers: The Important Role of Value-Added

    ERIC Educational Resources Information Center

    Glazerman, Steven; Loeb, Susanna; Goldhaber, Dan; Staiger, Douglas; Raudenbush, Stephen; Whitehurst, Grover

    2010-01-01

    The evaluation of teachers based on the contribution they make to the learning of their students, "value-added", is an increasingly popular but controversial education reform policy. In this report, the authors highlight and try to clarify four areas of confusion about value-added. The first is between value-added information and the…

  2. On integrability of D0-brane equations on AdS4 × Bbb CBbb P3 superbackground

    NASA Astrophysics Data System (ADS)

    Uvarov, D. V.

    2014-03-01

    Equations of motion for the D0-brane on AdS4 × Bbb CBbb P3 superbackground are shown to be classically integrable by extending the argument previously elaborated for the massless superparticle model.

  3. Gravitational collapse in the AdS background and the black hole formation

    NASA Astrophysics Data System (ADS)

    Allahyari, Alireza; Firouzjaee, Javad T.; Mansouri, Reza

    2016-10-01

    We study the time evolution of the Misner-Sharp mass and the apparent horizon for gravitational collapse of a massless scalar field in the AdS5 spacetime for both cases of narrow and broad waves by numerically solving the Einstein’s equations coupled to a massless scalar field. This is done by relying on the full dynamics of the collapse including the concept of the dynamical horizon. It turns out that the Misner-Sharp mass is everywhere constant except for a rapid change across a thin shell defined by the density profile of the collapsing wave. By studying the evolution of the apparent horizon, indicating the formation of a black hole at different times we see how asymptotically an event horizon forms. The dependence of the thermalization time on the radius of the initial black hole event horizon is also studied.

  4. Localized AdS5×S5 Black Holes

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

    According to heuristic arguments, global AdS5×S5 black holes are expected to undergo a phase transition in the microcanonical ensemble. At high energies, one expects black holes that respect the symmetries of the S5; at low energies, one expects "localized" black holes that appear pointlike on the S5. According to anti-de Sitter/conformal field theory correspondence, N =4 supersymmetric Yang-Mills (SYM) theory on a 3-sphere should therefore exhibit spontaneous R -symmetry breaking at strong coupling. In this Letter, we numerically construct these localized black holes. We extrapolate the location of this phase transition, and compute the expectation value of the broken scalar operator with lowest conformal dimension. Via the correspondence, these results offer quantitative predictions for N =4 SYM theory.

  5. All-loop Bethe ansatz equations for AdS3/CFT2

    NASA Astrophysics Data System (ADS)

    Borsato, Riccardo; Sax, Olof Ohlsson; Sfondrini, Alessandro

    2013-04-01

    Using the S-matrix for the {d}{{( {2, 1; α } )}^2} symmetric spin-chain of AdS3/CFT2, we propose a new set of all-loop Bethe equations for the system. These equations differ from the ones previously found in the literature by the choice of relative grading between the two copies of the {d}( {2, 1; α } ) superalgebra, and involve four undetermined scalar factors that play the role of dressing phases. Imposing crossing symmetry and comparing with the near-BMN form of the S-matrix found in the literature, we find several novel features. In particular, the scalar factors must differ from the Beisert-Eden-Staudacher phase, and should couple nodes of different masses to each other. In the semiclassical limit the phases are given by a suitable generalization of Arutyunov-Frolov-Staudacher phase.

  6. Holographic fermionic spectrum from Born-Infeld AdS black hole

    NASA Astrophysics Data System (ADS)

    Wu, Jian-Pin

    2016-07-01

    In this letter, we systematically explore the holographic (non-)relativistic fermionic spectrum without/with dipole coupling dual to Born-Infeld anti-de Sitter (BI-AdS) black hole. For the relativistic fermionic fixed point, this holographic fermionic system exhibits non-Fermi liquid behavior. Also, with the increase of BI parameter γ, the non-Fermi liquid becomes even "more non-Fermi". When the dipole coupling term is included, we find that the BI term makes it a lot tougher to form the gap. While for the non-relativistic fermionic system with large dipole coupling in BI-AdS background, with the increase of BI parameter, the gap comes into being again.

  7. Charge loss (or the lack thereof) for AdS black holes

    NASA Astrophysics Data System (ADS)

    Ong, Yen Chin; Chen, Pisin

    2014-06-01

    The evolution of evaporating charged black holes is complicated to model in general, but is nevertheless important since the hints to the Information Loss Paradox and its recent firewall incarnation may lie in understanding more generic geometries than that of Schwarzschild spacetime. Fortunately, for sufficiently large asymptotically flat Reissner-Nordström black holes, the evaporation process can be modeled via a system of coupled linear ordinary differential equations, with charge loss rate governed by Schwinger pair-production process. The same model can be generalized to study the evaporation of AdS Reissner-Nordström black holes with flat horizon. It was recently found that such black holes always evolve towards extremality since charge loss is inefficient. This property is completely opposite to the asymptotically flat case in which the black hole eventually loses its charges and tends towards Schwarzschild limit. We clarify the underlying reason for this different behavior.

  8. Holographic antiferromagnetic quantum criticality and AdS2 scaling limit

    NASA Astrophysics Data System (ADS)

    Cai, Rong-Gen; Yang, Run-Qiu; Kusmartsev, F. V.

    2015-08-01

    A holographic description on the antiferromagnetic quantum phase transition (QPT) induced by the magnetic field and the criticality in the vicinity of the quantum critical point have been investigated numerically recently. In this paper, we show that the properties of QPT in this holographic model are governed by a CFT dual to the emergent AdS2 in the IR region, which confirms that the dual boundary theory is a strong coupling theory with dynamic exponent z =2 and logarithmic corrections appearing. We also compare them with the results from the Hertz model by solving the RG equation at its upper critical dimension and with some experimental data from pyrochlores Er2 -2 xY2 xTi2 O7 and BiCoPO5 .

  9. Dyonic AdS 4 black hole entropy and attractors via entropy function

    NASA Astrophysics Data System (ADS)

    Goulart, Prieslei

    2016-09-01

    Using the Sen's entropy function formalism, we compute the entropy for the extremal dyonic black hole solutions of theories in the presence of dilaton field coupled to the field strength and a dilaton potential. We solve the attractor equations analytically and determine the near horizon metric, the value of the scalar fields and the electric field on the horizon, and consequently the entropy of these black holes. The attractor mechanism plays a very important role for these systems, and after studying the simplest systems involving dilaton fields, we propose a general solution for the value of the scalar field on the horizon, which allows us to solve the attractor equations for gauged supergravity theories in AdS 4 spaces. In particular, we derive an expression for the dyonic black hole entropy for the {N}=8 gauged supergravity in 4 dimensions which does not contain explicitly the gauge parameter of the potential.

  10. Massless sector of AdS3 superstrings: A geometric interpretation

    NASA Astrophysics Data System (ADS)

    Fontanella, Andrea; Torrielli, Alessandro

    2016-09-01

    We study the recently discovered q -deformed Poincaré supersymmetry of the AdS3/CFT2 integrable massless scattering, and demonstrate how the S -matrix is invariant under boosts. The boost generator has a nonlocal coproduct, which acts on the scattering matrix as a differential operator, annihilating it. We propose to reinterpret the boost action in terms of covariant derivatives on bundles, and derive an expression for the S -matrix as the path-ordered exponential of a flat connection. We provide a list of possible alternative interpretations of this emergent geometric picture, including a one-dimensional auxiliary Schrödinger problem. We support our claims by performing a simplified algebraic Bethe ansatz, which bears some resemblance to antiferromagnets.

  11. Minimal surfaces in q-deformed AdS5xS5

    NASA Astrophysics Data System (ADS)

    Kameyama, Takashi

    2016-01-01

    We study minimal surfaces in q-deformed AdS5×S5. For this purpose, it is convenient to introduce a coordinate system which describes the spacetime only inside the singularity surface and treat the singularity surface as the holographic screen. In particular, we consider minimal surfaces whose boundary shapes are 1) a straight line and 2) a circle. In the q → 1 limit, the solutions correspond to a 1/2 BPS straight line Wilson loop and a 1/2 BPS circular one, respectively. A remarkable point is that the classical Euclidean actions have no linear divergence unlike the original ones. This finiteness indicates that the q-deformation may be regarded as a UV regularization.

  12. Holographic cusped Wilson loops in q-deformed AdS5 × S5 spacetime

    NASA Astrophysics Data System (ADS)

    Bai, Nan; Chen, Hui-Huang; Wu, Jun-Bao

    2015-10-01

    In this paper, a minimal surface in q-deformed AdS5×S5 with a cusp boundary is studied in detail. This minimal surface is dual to a cusped Wilson loop in dual field theory. We find that the area of the minimal surface has both logarithmic squared divergence and logarithmic divergence. The logarithmic squared divergence cannot be removed by either Legendre transformation or the usual geometric subtraction. We further make an analytic continuation to the Minkowski signature, taking the limit such that the two edges of the cusp become light-like, and extract the anomalous dimension from the coefficient of the logarithmic divergence. This anomalous dimension goes back smoothly to the results in the undeformed case when we take the limit that the deformation parameter goes to zero. Supported by National Natural Science Foundation of China (11105154, 11222549, 11275207), K. C. Wong Education Foundation and Youth Innovation Promotion Association of CAS

  13. Dyonic AdS 4 black hole entropy and attractors via entropy function

    NASA Astrophysics Data System (ADS)

    Goulart, Prieslei

    2016-09-01

    Using the Sen's entropy function formalism, we compute the entropy for the extremal dyonic black hole solutions of theories in the presence of dilaton field coupled to the field strength and a dilaton potential. We solve the attractor equations analytically and determine the near horizon metric, the value of the scalar fields and the electric field on the horizon, and consequently the entropy of these black holes. The attractor mechanism plays a very important role for these systems, and after studying the simplest systems involving dilaton fields, we propose a general solution for the value of the scalar field on the horizon, which allows us to solve the attractor equations for gauged supergravity theories in AdS 4 spaces. In particular, we derive an expression for the dyonic black hole entropy for the N=8 gauged supergravity in 4 dimensions which does not contain explicitly the gauge parameter of the potential.

  14. Boundary conditions and partition functions in higher spin AdS3/CFT2

    NASA Astrophysics Data System (ADS)

    de Boer, Jan; Jottar, Juan I.

    2016-04-01

    We discuss alternative definitions of the semiclassical partition function in two-dimensional CFTs with higher spin symmetry, in the presence of sources for the higher spin currents. Theories of this type can often be described via Hamiltonian reduction of current algebras, and a holographic description in terms of three-dimensional Chern-Simons theory with generalized AdS boundary conditions becomes available. By studying the CFT Ward identities in the presence of sources, we determine the appropriate choice of boundary terms and boundary conditions in Chern-Simons theory for the various types of partition functions considered. In particular, we compare the Chern-Simons description of deformations of the field theory Hamiltonian versus those encoding deformations of the CFT action. Our analysis clarifies various issues and confusions that have permeated the literature on this subject.

  15. Thermodynamic volumes for AdS-Taub-NUT and AdS-Taub-Bolt

    NASA Astrophysics Data System (ADS)

    Johnson, Clifford V.

    2014-12-01

    In theories of semi-classical quantum gravity where the cosmological constant is considered a thermodynamic variable, the gravitational mass of a black hole has been shown to correspond to the enthalpy of the thermodynamic system, rather than the energy. We propose that this should be extended to all spacetime solutions, and consider the meaning of this extension of gravitational thermodynamics for the Taub-NUT and Taub-Bolt geometries in four dimensional locally anti-de Sitter spacetime. We present formulae for their thermodynamic volumes. Surprisingly, Taub-NUT has negative volume, for which there is a natural dynamical explanation in terms of the process of formation of the spacetime. A special case corresponds to pure AdS4 with an S3 slicing. The same dynamical setting can explain the negative entropy known to exist for these solutions for a range of parameters.

  16. Holographic phase transition from dyons in an AdS black hole background

    NASA Astrophysics Data System (ADS)

    Lugo, A. R.; Moreno, E. F.; Schaposnik, F. A.

    2010-03-01

    We construct a dyon solution for a Yang-Mills-Higgs theory in a 4 dimensional Schwarzschild-anti-de Sitter black hole background with temperature T. We then apply the AdS/CFT correspondence to describe the strong coupling regime of a 2 + 1 quantum field theory which undergoes a phase transition exhibiting the condensation of a composite charge operator below a critical temperature T c .

  17. Boundary conditions for General Relativity on AdS3 and the KdV hierarchy

    NASA Astrophysics Data System (ADS)

    Pérez, Alfredo; Tempo, David; Troncoso, Ricardo

    2016-06-01

    It is shown that General Relativity with negative cosmological constant in three spacetime dimensions admits a new family of boundary conditions being labeled by a nonnegative integer k. Gravitational excitations are then described by "boundary gravitons" that fulfill the equations of the k-th element of the KdV hierarchy. In particular, k = 0 corresponds to the Brown-Henneaux boundary conditions so that excitations are described by chiral movers. In the case of k = 1, the boundary gravitons fulfill the KdV equation and the asymptotic symmetry algebra turns out to be infinite-dimensional, abelian and devoid of central extensions. The latter feature also holds for the remaining cases that describe the hierarchy ( k > 1). Our boundary conditions then provide a gravitational dual of two noninteracting left and right KdV movers, and hence, boundary gravitons possess anisotropic Lifshitz scaling with dynamical exponent z = 2 k + 1. Remarkably, despite spacetimes solving the field equations are locally AdS, they possess anisotropic scaling being induced by the choice of boundary conditions. As an application, the entropy of a rotating BTZ black hole is precisely recovered from a suitable generalization of the Cardy formula that is compatible with the anisotropic scaling of the chiral KdV movers at the boundary, in which the energy of AdS spacetime with our boundary conditions depends on z and plays the role of the central charge. The extension of our boundary conditions to the case of higher spin gravity and its link with different classes of integrable systems is also briefly addressed.

  18. Receiver-Based Ad Hoc On Demand Multipath Routing Protocol for Mobile Ad Hoc Networks.

    PubMed

    Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha

    2016-01-01

    Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV. PMID:27258013

  19. Receiver-Based Ad Hoc On Demand Multipath Routing Protocol for Mobile Ad Hoc Networks

    PubMed Central

    Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha

    2016-01-01

    Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV. PMID:27258013

  20. Receiver-Based Ad Hoc On Demand Multipath Routing Protocol for Mobile Ad Hoc Networks.

    PubMed

    Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha

    2016-01-01

    Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV.

  1. Three dimensional nonlinear magnetic AdS solutions through topological defects

    NASA Astrophysics Data System (ADS)

    Hendi, S. H.; Panah, B. Eslam; Momennia, M.; Panahiyan, S.

    2015-09-01

    Inspired by large applications of topological defects in describing different phenomena in physics, and considering the importance of three dimensional solutions in AdS/CFT correspondence, in this paper we obtain magnetic anti-de Sitter solutions of nonlinear electromagnetic fields. We take into account three classes of nonlinear electrodynamic models; first two classes are the well-known Born-Infeld like models including logarithmic and exponential forms and third class is known as the power Maxwell invariant nonlinear electrodynamics. We investigate the effects of these nonlinear sources on three dimensional magnetic solutions. We show that these asymptotical AdS solutions do not have any curvature singularity and horizon. We also generalize the static metric to the case of rotating solutions and find that the value of the electric charge depends on the rotation parameter. Finally, we consider the quadratic Maxwell invariant as a correction of Maxwell theory and we investigate the effects of nonlinearity as a correction. We study the behavior of the deficit angle in presence of these theories of nonlinearity and compare them with each other. We also show that some cases with negative deficit angle exists which are representing objects with different geometrical structure. We also show that in case of the static only magnetic field exists whereas by boosting the metric to rotating one, electric field appears too.

  2. Superradiant instability of five-dimensional rotating charged AdS black holes

    SciTech Connect

    Aliev, Alikram N.; Delice, Oezguer

    2009-01-15

    We study the instability of small AdS black holes with two independent rotation parameters in minimal five-dimensional gauged supergravity to massless scalar perturbations. We analytically solve the Klein-Gordon equation for low-frequency perturbations in two regions of the spacetime of these black holes: namely, in the region close to the horizon and in the far-region. By matching the solutions in an intermediate region, we calculate the frequency spectrum of quasinormal modes. We show that in the regime of superradiance only the modes of even orbital quantum number undergo negative damping, resulting in exponential growth of the amplitude. That is, the black holes become unstable to these modes. Meanwhile, the modes of odd orbital quantum number do not undergo any damping, oscillating with frequency-shifts. This is in contrast with the case of four-dimensional small Kerr-AdS black holes which exhibit the instability to all modes of scalar perturbations in the regime of superradiance.

  3. BPS preons and the AdS-M-algebra

    NASA Astrophysics Data System (ADS)

    Bandos, Igor A.; de Azcárraga, José A.

    2008-04-01

    We present here the AdS generalization of BPS preons, which were introduced as the hypothetical constituents of M-theory preserving all but one supersymmetries. Our construction, suggested by the relation of `lower dimensional preons' with higher spin theories, can be considered as a deformation of the M-algebraic description of the single supersymmetry broken by a preon, and provides another reason to identify the AdS generalization of the M-algebra, which we call the AdS-M-algebra, with osp(1|32).

  4. Nearly Conformal QCD and AdS/CFT

    SciTech Connect

    de Teramond, Guy F.; Brodsky, Stanley J.; /Costa Rica U. /SLAC

    2005-08-08

    The AdS/CFT correspondence is a powerful tool to study the properties of conformal QCD at strong coupling in terms of a higher dimensional dual gravity theory. The power-law falloff of scattering amplitudes in the non-perturbative regime and calculable hadron spectra follow from holographic models dual to QCD with conformal behavior at short distances and confinement at large distances. String modes and fluctuations about the AdS background are identified with QCD degrees of freedom and orbital excitations at the AdS boundary limit. A description of form factors in space and time-like regions and the behavior of light-front wave functions can also be understood in terms of a dual gravity description in the interior of AdS.

  5. Ausbildung als zentrale Aufgabe

    NASA Astrophysics Data System (ADS)

    Krämer, Walter; Schmerbach, Sibylle

    Anders als Lesen und Schreiben zählen Grundkenntnisse in Statistik heute noch nicht zu den Voraussetzungen einer sinnvollen Teilhabe am Sozialgeschehen. Und auch in der akademischen Statistik-Ausbildung gibt es noch einiges zu tun. Das vorliegende Kapitel zeichnet die Geschichte dieser akademischen Ausbildung an deutschen Universitäten nach dem zweiten Weltkrieg nach, stellt aktuelle Defizite vor und weist auf mögliche Verbesserungen hin.

  6. Al-Akhawayni and the early descriptions of meningitis.

    PubMed

    Dalfardi, Behnam; Yarmohammadi, Hassan; Sedighi, Mahsa; Zargaran, Arman

    2014-01-01

    Abubakr Rabi-ibn Ahmad Akhawayni Bukhari, also known as Al-Akhawayni, was a Persian physician who lived in the Near East during an age in which medical knowledge blossomed in the Islamic world. This era, the "Islamic Golden Age," extended from the tenth to the twelfth centuries AD. During his lifetime as a physician, Al-Akhawayni was famous for his expertise in medicine, including disorders that would be considered neurological today. In his extant book Hidayat al-Muta`allemin fi al-Tibb [A Scholar's Guide to Medicine], he provided an early description of what is probably meningitis. He illustrated the membranes surrounding the brain tissue in detail and described manifestations resulting from their inflammation.

  7. Efficacy of adding folic acid to foods.

    PubMed

    Fajardo, Violeta; Varela-Moreiras, Gregorio

    2012-06-01

    In the past, food fortification along with nutritional education and the decrease in food costs relative to income have proven successful in eliminating common nutritional deficiencies. These deficiencies such as goiter, rickets, beriberi, and pellagra have been replaced with an entirely new set of "emergent deficiencies" that were not previously considered a problem [e.g., folate and neural tube defects (NTDs)]. In addition, the different nutrition surveys in so-called affluent countries have identified "shortfalls" of nutrients specific to various age groups and/or physiological status. Complex, multiple-etiology diseases, such as atherosclerosis, diabetes, cancer, and obesity have emerged. Food fortification has proven an effective tool for tackling nutritional deficiencies in populations; but today a more reasonable approach is to use food fortification as a means to support but not replace dietary improvement strategies (i. e. nutritional education campaigns). Folic acid (FA) is a potential relevant factor in the prevention of a number of pathologies. The evidence linking FA to NTD prevention led to the introduction of public health strategies to increase folate intakes: pharmacological supplementation, mandatory or voluntary fortification of staple foods with FA, and the advice to increase the intake of folate-rich foods. It is quite contradictory to observe that, regardless of these findings, there is only limited information on food folate and FA content. Data in Food Composition Tables and Databases are scarce or incomplete. Fortification of staple foods with FA has added difficulty to this task. Globally, the decision to fortify products is left up to individual food manufacturers. Voluntary fortification is a common practice in many countries. Therefore, the "worldwide map of vitamin fortification" may be analyzed. It is important to examine if fortification today really answers to vitamin requirements at different ages and/or physiological states. The

  8. What makes an ad a cigarette ad? Commercial tobacco imagery in the lesbian, gay, and bisexual press

    PubMed Central

    Smith, E.; Offen, N.; Malone, R.

    2005-01-01

    Objectives: To determine the extent of commercial tobacco imagery in the lesbian, gay, and bisexual (LGB) press. Methods: Content analysis of all advertising containing tobacco related text or imagery in 20 LGB community periodicals, published between January 1990 and December 2000. Results: 3428 ads were found: 689 tobacco product ads, 1607 ads for cessation products or services, 99 ads with a political message about tobacco, and 1033 non-tobacco ads that showed tobacco (NAST). Although cessation ads were numerically dominant, tobacco product ads and NAST occupied more space and were more likely to use images. NAST almost never had an anti-tobacco message. Formal sponsorship between tobacco and other companies was very rare. Lesbian periodicals had proportionally more NAST and fewer cessation ads. Conclusions: Cigarette ads were outnumbered by NAST. Although these ads do not usually show brands, and are unlikely to be the result of formal sponsorship agreements, they may be "selling" smoking. Tobacco control advocates should persuade editors to refuse tobacco product ads and those with gratuitous tobacco imagery. PMID:16286500

  9. Introduction to the AdS/CFT Correspondence

    NASA Astrophysics Data System (ADS)

    Nąstase, Horaǧiu

    2015-09-01

    Preface; Introduction; Part I. Background: 1. Elements of quantum field theory and gauge theory; 2. Basics of general relativity. Anti-de Sitter space; 3. Basics of supersymmetry; 4. Basics of supergravity; 5. Kaluza-Klein dimensional reduction; 6. Black holes and p-branes; 7. String theory actions and spectra; 8. Elements of conformal field theory; 9. D-branes; Part II. Basics of AdS/CFT for N = 4 SYM vs AdS5 × S5: 10. The AdS/CFT correspondence: motivation, definition and spectra; 11. Witten prescription and 3-point correlator calculations; 12. Holography in Lorentzian signature: Poincaré and global; 13. Solitonic objects in AdS/CFT; 14. Quarks and the Wilson loop; 15. Finite temperature and N = 4 SYM plasmas; 16. Scattering processes and gravitational shockwave limit; 17. The pp-wave correspondence; 18. Spin chains; Part III. AdS/CFT Developments and Gauge-Gravity Dualities: 19. Other conformal cases; 20. The 3 dimensional ABJM model vs. AdS4 × CP3; 21. Gravity duals; 22. Holographic renormalization; 23. RG flow between fixed points; 24. Phenomenological gauge-gravity duality I: AdS/QCD; 25. Phenomenological gauge-gravity duality II: AdS/CMT; 26. Gluon scattering: the Alday-Maldacena prescription; 27. Holographic entanglement entropy: the Ryu-Takayanagi prescription.

  10. Effect of added mass on the interaction of bubbles in a low-Reynolds-number shear flow.

    PubMed

    Lavrenteva, Olga; Prakash, Jai; Nir, Avinoam

    2016-02-01

    Equal size air bubbles that are entrapped by a Taylor vortex of the secondary flow in a Couette device, thereby defying buoyancy, slowly form a stable ordered ring with equal separation distances between all neighbors. We present two models of the process dynamics based on force balance on a bubble in the presence of other bubbles positioned on the same streamline in a simple shear flow. The forces taken into account are the viscous resistance, the added mass force, and the inertia-induced repulsing force between two bubbles in a low-Reynolds-number shear flow obtained in Prakash et al. [J. Prakash et al., Phys. Rev. E 87, 043002 (2013)]. The first model of the process assumes that each bubble interacts solely with its nearest neighbors. The second model takes into account pairwise interactions among all the bubbles in the ring. The performed dynamic simulations were compared to the experimental results reported in Prakash et al. [J. Prakash et al., Phys. Rev. E 87, 043002 (2013)] and to the results of quasistationary models (ignoring the added mass effect) suggested in that paper. It is demonstrated that taking into account the effect of added mass, the models describe the major effect of the bubbles' ordering, provide good estimation of the relaxation time, and also predict nonmonotonic behavior of the separation distance between the bubbles, which exhibit over- and undershooting of equilibrium separations. The latter effects were observed in experiments, but are not predicted by the quasistationary models.

  11. Effect of added mass on the interaction of bubbles in a low-Reynolds-number shear flow.

    PubMed

    Lavrenteva, Olga; Prakash, Jai; Nir, Avinoam

    2016-02-01

    Equal size air bubbles that are entrapped by a Taylor vortex of the secondary flow in a Couette device, thereby defying buoyancy, slowly form a stable ordered ring with equal separation distances between all neighbors. We present two models of the process dynamics based on force balance on a bubble in the presence of other bubbles positioned on the same streamline in a simple shear flow. The forces taken into account are the viscous resistance, the added mass force, and the inertia-induced repulsing force between two bubbles in a low-Reynolds-number shear flow obtained in Prakash et al. [J. Prakash et al., Phys. Rev. E 87, 043002 (2013)]. The first model of the process assumes that each bubble interacts solely with its nearest neighbors. The second model takes into account pairwise interactions among all the bubbles in the ring. The performed dynamic simulations were compared to the experimental results reported in Prakash et al. [J. Prakash et al., Phys. Rev. E 87, 043002 (2013)] and to the results of quasistationary models (ignoring the added mass effect) suggested in that paper. It is demonstrated that taking into account the effect of added mass, the models describe the major effect of the bubbles' ordering, provide good estimation of the relaxation time, and also predict nonmonotonic behavior of the separation distance between the bubbles, which exhibit over- and undershooting of equilibrium separations. The latter effects were observed in experiments, but are not predicted by the quasistationary models. PMID:26986411

  12. ``A red cross appeared in the sky'' and other celestial signs: Presumable European aurorae in the mid AD 770s were halo displays

    NASA Astrophysics Data System (ADS)

    Neuhäuser, D. L.; Neuhäuser, R.

    2015-12-01

    The interpretation of the strong 14C variation around AD 775 as one (or several) solar super-flare(s) by, e.g., Usoskin et al. (2013) is based on alleged aurora sightings in the mid AD 770s in Europe: A red cross/crucifix in AD 773/4/6 from the Anglo-Saxon Chronicle, inflamed shields in AD 776 (both listed in the aurora catalogue of Link 1962), and riders on white horses in AD 773 (newly proposed as aurora in Usoskin et al. 2013), the two latter from the Royal Frankish Annals. We discuss the reports about these three sightings in detail here. We can show that all three can be interpreted convincingly as halo displays: The red cross or crucifix is formed by the horizontal arc and a vertical pillar of light (either with the Sun during sunset or with the moon after sunset); the inflamed shields and the riders on white horses were both two mock suns, especially the latter narrated in form of a Christian adaptation of the antique dioscuri motive. While the latter event took place early in AD 774 (dated AD 773 in Usoskin et al. 2013), the two other sightings have to be dated AD 776, i.e. anyway too late for being in connection with a 14C rise that started before AD 775. We also sketch the ideological background of those sightings and there were many similar reports throughout that time. In addition, we present a small drawing of a lunar halo display with horizontal arc and vertical pillar forming a cross for shortly later, namely AD 806 June 4, the night of full moon, also from the Anglo-Saxon Chronicle; we also show historic observations of halo phenomena (mock suns and crosses) from G. Kirch and Hevelius - and a modern photograph.

  13. Removing Al and regenerating caustic soda from the spent washing liquor of Al etching

    NASA Astrophysics Data System (ADS)

    Barakat, M. A.; El-Sheikh, S. M.; Farghly, F. E.

    2005-08-01

    Spent liquor from washing of aluminum section materials after etching with caustic soda (NaOH) has been treated. Aluminum was removed from the liquor and caustic soda was regenerated by adding precipitating agents to hydrolyze sodium aluminate (Na2AlO2), separating the aluminumprecipitate, and concentrating free NaOH in the resulting solution for reuse in the etching process. Four systems were investigated: hydrated lime [Ca(OH)2], hydrogen peroxide (H2O2), H2O2/Ca(OH)2 mixture, and dry lime (CaO). Results revealed that CaO was more efficient in the removal of aluminum from the spent liquor with a higher hydrolyzing rate of Na2AlO2 than Ca(OH)2, H2O2, or their mixture.

  14. Influence of Process Control Agents on Mechanochemical Synthesis of NiAl/Al2O3 Nano Composite powder

    NASA Astrophysics Data System (ADS)

    Heshmati-Manesh, S.; Jabbarnia, A.

    2010-03-01

    Mechanochemical synthesis of an intermetallic NiAl matrix nano composite powder has been studied in this paper. Micron sized powders of nickel oxide (NiO) and aluminum powders were subjected to high energy ball milling under an argon protected atmosphere. According to an exothermic exchange reaction assisted by high energy ball milling, nickel oxide is reduced by Al and a NiAl/Al2O3 composite powder is produced. The process was also examined when stearic acid and methanol were added as process control agents (PCAs) to the reactants and it was found that their addition hinders the reduction reaction. The effect of further milling on the milling behavior of the resulting composite powder has also been investigated. The morphology and phase composition of the milling products were evaluated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis.

  15. Matrix model maps and reconstruction of AdS supergravity interactions

    SciTech Connect

    Cremonini, Sera; Mello Koch, Robert de; Jevicki, Antal

    2008-05-15

    We consider the question of reconstructing (cubic) SUGRA interactions in AdS/CFT. The method we introduce is based on the matrix model maps (MMP) which were previously successfully employed at the linearized level. The strategy is to start with the map for 1/2 BPS configurations, which is exactly known (to all orders) in the Hamiltonian framework. We then use the extension of the matrix model map with the corresponding Ward identities to completely specify the interaction. A central point in this construction is the nonvanishing of off-shell interactions (even for highest-weight states)

  16. The forecaster's added value in QPF

    NASA Astrophysics Data System (ADS)

    Turco, M.; Milelli, M.

    2010-03-01

    : - despite the overall improvement in global scale and the fact that the resolution of the limited area models has increased considerably over recent years, the QPF produced by the meteorological models involved in this study has not improved enough to allow its direct use: the subjective HQPF continues to offer the best performance for the period +24 h/+48 h (i.e. the warning period in the Piemonte system); - in the forecast process, the step where humans have the largest added value with respect to mathematical models, is the communication. In fact the human characterization and communication of the forecast uncertainty to end users cannot be replaced by any computer code; - eventually, although there is no novelty in this study, we would like to show that the correct application of appropriated statistical techniques permits a better definition and quantification of the errors and, mostly important, allows a correct (unbiased) communication between forecasters and decision makers.

  17. [Separation and purification of Al13 by chemical precipitation and metathesis].

    PubMed

    Li, Guo-Hong; Shi, Bao-You; Wang, Dong-Sheng; Cui, Ya-Li

    2007-02-01

    PACls with different concentrations were prepared by adding sodium carbonate powder into AlCl13 solution. Medium concentration and high Al13 content of PACl was chosen to carry out Al13 separation processes. The influences of SO4/Al molar ratio and the initial total Al concentration on the precipitation reactions of sulfate with different Al species were investigated. The factors influencing the metathesis reaction between solid Al13-SO4 and Ba(NO3)2 were evaluated. Results showed that high Al13 PACl could be obtained at the medium high concentration range of 0.4 - 0.6 mol/L, the optimum SO4/Al ratio was 0.6:1 for precipitation- separation of Al13, Al13 -SO4 precipitates were mostly consisted of tetrahedral crystals. During the metathesis reaction, Ba/SO4 molar ratio of 1:1 is the optimal value. Small range temperature variation and ultrasonic action had no marked influence on metathesis reaction rate and final Al13 concentration. Higher initial Ba(NO3)2 concentration could produce higher concentration Al13 accordingly. The purity of Al13 solution could be reached to 92.1% statistically.

  18. 40Ar/39Ar ages of the AD 79 eruption of Vesuvius, Italy

    USGS Publications Warehouse

    Lanphere, M.; Champion, D.; Melluso, L.; Morra, V.; Perrotta, A.; Scarpati, C.; Tedesco, D.; Calvert, A.

    2007-01-01

    The Italian volcano, Vesuvius, erupted explosively in AD 79. Sanidine from pumice collected at Casti Amanti in Pompeii and Villa Poppea in Oplontis yielded a weighted-mean 40Ar/39Ar age of 1925??66 years in 2004 (1?? uncertainty) from incremental-heating experiments of eight aliquants of sanidine. This is the calendar age of the eruption. Our results together with the work of Renne et al. (1997) and Renne and Min (1998) demonstrate the validity of the 40Ar/39Ar method to reconstruct the recent eruptive history of young, active volcanoes. ?? Springer-Verlag 2006.

  19. 1-loop partition function in AdS 3/ CFT 2

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Wu, Jie-qiang

    2015-12-01

    The 1-loop partition function of the handlebody solutions in the AdS3 gravity have been derived some years ago using the heat kernel techniques and the method of images. In the semiclassical limit, such partition function should correspond to the order O( c 0) part in the partition function of dual conformal field theory(CFT) on the boundary Riemann surface. The higher genus partition function could be computed by the multi-point functions in the Riemann sphere via sewing prescription. In the large central charge limit, the CFT is effectively free in the sense that to the leading order of c the multi-point function is further simplified to be a summation over the products of two-point functions of single-particle states. Correspondingly in the bulk, the graviton is freely propagating without interaction. Furthermore the product of the two-point functions may define the links, each of which is in one-to-one correspondence with the conjugacy class of the Schottky group of the Riemann surface. Moreover, the value of a link is determined by the multiplier of the element in the conjugacy class. This allows us to reproduce exactly the gravitational 1-loop partition function. The proof can be generalized to the higher spin gravity and its dual CFT.

  20. Unfolding mixed-symmetry fields in AdS and the BMV conjecture: II. Oscillator realization

    NASA Astrophysics Data System (ADS)

    Boulanger, Nicolas; Iazeolla, Carlo; Sundell, Per

    2009-07-01

    Following the general formalism presented in arXiv:0812.3615 — referred to as Paper I — we derive the unfolded equations of motion for tensor fields of arbitrary shape and mass in constantly curved backgrounds by radial reduction of Skvortsov's equations in one higher dimension. The complete unfolded system is embedded into a single master field, valued in a tensorial Schur module realized equivalently via either bosonic (symmetric basis) or fermionic (anti-symmetric basis) vector oscillators. At critical masses the reduced Weyl zero-form modules become indecomposable. We explicitly project the latter onto the submodules carrying Metsaev's massless representations. The remainder of the reduced system contains a set of Stückelberg fields and dynamical potentials that leads to a smooth flat limit in accordance with the Brink-Metsaev-Vasiliev (BMV) conjecture. In the unitary massless cases in AdS, we identify the Alkalaev-Shaynkman-Vasiliev frame-like potentials and explicitly disentangle their unfolded field equations.

  1. Analytic self-gravitating Skyrmions, cosmological bounces and AdS wormholes

    NASA Astrophysics Data System (ADS)

    Ayón-Beato, Eloy; Canfora, Fabrizio; Zanelli, Jorge

    2016-01-01

    We present a self-gravitating, analytic and globally regular Skyrmion solution of the Einstein-Skyrme system with winding number w = ± 1, in presence of a cosmological constant. The static spacetime metric is the direct product R ×S3 and the Skyrmion is the self-gravitating generalization of the static hedgehog solution of Manton and Ruback with unit topological charge. This solution can be promoted to a dynamical one in which the spacetime is a cosmology of the Bianchi type-IX with time-dependent scale and squashing coefficients. Remarkably, the Skyrme equations are still identically satisfied for all values of these parameters. Thus, the complete set of field equations for the Einstein-Skyrme-Λ system in the topological sector reduces to a pair of coupled, autonomous, nonlinear differential equations for the scale factor and a squashing coefficient. These equations admit analytic bouncing cosmological solutions in which the universe contracts to a minimum non-vanishing size, and then expands. A non-trivial byproduct of this solution is that a minor modification of the construction gives rise to a family of stationary, regular configurations in General Relativity with negative cosmological constant supported by an SU (2) nonlinear sigma model. These solutions represent traversable AdS wormholes with NUT parameter in which the only "exotic matter" required for their construction is a negative cosmological constant.

  2. Gribov ambiguity in asymptotically AdS three-dimensional gravity

    SciTech Connect

    Anabalon, Andres; Canfora, Fabrizio; Giacomini, Alex; Oliva, Julio

    2011-03-15

    In this paper the zero modes of the de Donder gauge Faddeev-Popov operator for three-dimensional gravity with negative cosmological constant are analyzed. It is found that the AdS{sub 3} vacuum produces (infinitely many) normalizable smooth zero modes of the Faddeev-Popov operator. On the other hand, it is found that the Banados-Teitelboim-Zanelli black hole (including the zero mass black hole) does not generate zero modes. This differs from the usual Gribov problem in QCD where, close to the maximally symmetric vacuum, the Faddeev-Popov determinant is positive definite while 'far enough' from the vacuum it can vanish. This suggests that the zero mass Banados-Teitelboim-Zanelli black hole could be a suitable ground state of three-dimensional gravity with negative cosmological constant. Because of the kinematic origin of this result, it also applies for other covariant gravity theories in three dimensions with AdS{sub 3} as maximally symmetric solution, such as new massive gravity and topologically massive gravity. The relevance of these results for supersymmetry breaking is pointed out.

  3. Progress report for the ASCI AD resistance weld process modeling project AD2003-15.

    SciTech Connect

    Brown, Arthur A.; Winters, William S.; Bammann, Douglas J.; Ortega, Arthur R.; Foulk, James W., III

    2005-05-01

    This report documents activities related to the ASCI AD Resistance Weld Process Modeling Project AD2003-15. Activities up to and including FY2004 are discussed. This was the third year for this multi year project, the objective of which is to position the SIERRA computational tools for the solution of resistance welding problems. The process of interest is a three-way coupled problem involving current flow, temperature buildup and large plastic deformation. The DSW application is the reclamation stem weld used in the manufacture of high pressure gas bottles. This is the first year the CALAGIO suite of codes (eCALORE, CALORE, and ADAGIO) was used to successfully solve a three-way coupled problem in SIERRA. This report discusses the application of CALAGIO to the tapered bar acceptance problem and a similar but independent tapered bar simulation of a companion C6 experiment. New additions to the EMMI constitutive model and issues related to CALAGIO performance are also discussed.

  4. Warped AdS 6 × S 2 in Type IIB supergravity I: local solutions

    NASA Astrophysics Data System (ADS)

    D'Hoker, Eric; Gutperle, Michael; Karch, Andreas; Uhlemann, Christoph F.

    2016-08-01

    We investigate the existence of solutions with 16 residual supersymmetries to Type IIB supergravity on a space-time of the formc AdS 6× S 2 warped over a two-dimensional Riemann surface Σ. The SO(2 , 5) × SO(3) isometry extends to invariance under the exceptional Lie superalgebra F (4). In the present paper, we construct the general Ansatz compatible with these symmetries, derive the corresponding reduced BPS equations, and obtain their complete local solution in terms of two locally holomorphic functions {A}_{± } on Σ, subject to certain positivity and regularity conditions. Globally, ( {A}+ , {A}- ) are allowed to be multiple-valued on Σ and be holomorphic sections of a holomorphic bundle over Σ with structure group contained in SU(1,1)× C . Globally regular solutions are expected to provide the near-horizon geometry of ( p, q) 5-brane and 7-brane webs which are holographic duals to five-dimensional conformal field theories. A preliminary analysis of the positivity and regularity conditions will be presented here, leaving the construction of globally regular solutions to a subsequent paper.

  5. Bosonic excitations of the AdS 4 Reissner-Nordstrom black hole

    NASA Astrophysics Data System (ADS)

    Davison, Richard A.; Kaplis, Nikolaos K.

    2011-12-01

    We study the long-lived modes of the charge density and energy density correla- tors in the strongly-coupled, finite density field theory dual to the AdS 4 Reissner-Nordstrom black hole. For small momenta q ≪ μ , these correlators contain a pole due to sound propagation, as well as a pole due to a long-lived, purely imaginary mode analogous to the μ = 0 hydrodynamic charge diffusion mode. As the temperature is raised in the range T{\\underset{raise0.3emsmashriptscriptstylethicksim}{ < }}μ , the sound attenuation shows no significant temperature dependence. When T{\\underset{raise0.3emsmashriptscriptstylethicksim}{ > }}μ , it quickly approaches the μ = 0 hydrodynamic result where it decreases like 1/ T. It does not share any of the temperature-dependent properties of the `zero sound' of Landau Fermi liquids observed in the strongly-coupled D3/D7 field theory. For such small momenta, the energy density spectral function is dominated by the sound mode at all temperatures, whereas the charge density spectral function undergoes a crossover from being dominated by the sound mode at low temperatures to being dominated by the diffusion mode when T ˜ {μ^2}/q . This crossover occurs due to the changing residue at each pole. We also compute the momentum dependence of these spectral functions and their corresponding long-lived poles at fixed, low temperatures T ≪ μ.

  6. S -matrix algebra of the AdS2×S2 superstring

    NASA Astrophysics Data System (ADS)

    Hoare, Ben; Pittelli, Antonio; Torrielli, Alessandro

    2016-03-01

    In this paper, we find the Yangian algebra responsible for the integrability of the AdS2×S2×T6 superstring in the planar limit. We demonstrate the symmetry of the corresponding exact S matrix in the massive sector, including the presence of the secret symmetry. We give two alternative presentations of the Hopf algebra. The first takes the usual canonical form, which, as the relevant representations are long, leads to a Yangian representation that is not of evaluation type. After investigating the relationship between cocommutativity, evaluation representations and the shortening condition, we find an alternative realization of the Yangian whose representation is of the evaluation type. Finally, we explore two limits of the S matrix. The first is the classical r matrix, where we rediscover the need for a secret symmetry also in this context. The second is the simplifying zero-coupling limit. In this limit, taking the S matrix as a generating R matrix for the algebraic Bethe ansatz, we obtain an effective model of free fermions on a periodic spin-chain. This limit should provide hints to the one-loop anomalous dimension of the mysterious superconformal quantum mechanics dual to the superstring theory in this geometry.

  7. Symplectic and Killing symmetries of AdS3 gravity: holographic vs boundary gravitons

    NASA Astrophysics Data System (ADS)

    Compère, G.; Mao, P.; Seraj, A.; Sheikh-Jabbari, M. M.

    2016-01-01

    The set of solutions to the AdS3 Einstein gravity with Brown-Henneaux boundary conditions is known to be a family of metrics labeled by two arbitrary periodic functions, respectively left and right-moving. It turns out that there exists an appropriate presymplectic form which vanishes on-shell. This promotes this set of metrics to a phase space in which the Brown-Henneaux asymptotic symmetries become symplectic symmetries in the bulk of spacetime. Moreover, any element in the phase space admits two global Killing vectors. We show that the conserved charges associated with these Killing vectors commute with the Virasoro symplectic symmetry algebra, extending the Virasoro symmetry algebra with two U(1) generators. We discuss that any element in the phase space falls into the coadjoint orbits of the Virasoro algebras and that each orbit is labeled by the U(1) Killing charges. Upon setting the right-moving function to zero and restricting the choice of orbits, one can take a near-horizon decoupling limit which preserves a chiral half of the symplectic symmetries. Here we show two distinct but equivalent ways in which the chiral Virasoro symplectic symmetries in the near-horizon geometry can be obtained as a limit of the bulk symplectic symmetries.

  8. Asymptotic structure of the Einstein-Maxwell theory on AdS3

    NASA Astrophysics Data System (ADS)

    Pérez, Alfredo; Riquelme, Miguel; Tempo, David; Troncoso, Ricardo

    2016-02-01

    The asymptotic structure of AdS spacetimes in the context of General Relativity coupled to the Maxwell field in three spacetime dimensions is analyzed. Although the fall-off of the fields is relaxed with respect to that of Brown and Henneaux, the variation of the canonical generators associated to the asymptotic Killing vectors can be shown to be finite once required to span the Lie derivative of the fields. The corresponding surface integrals then acquire explicit contributions from the electromagnetic field, and become well-defined provided they fulfill suitable integrability conditions, implying that the leading terms of the asymptotic form of the electromagnetic field are functionally related. Consequently, for a generic choice of boundary conditions, the asymptotic symmetries are broken down to {R}⊗ U(1)⊗ U(1) . Nonetheless, requiring compatibility of the boundary conditions with one of the asymptotic Virasoro symmetries, singles out the set to be characterized by an arbitrary function of a single variable, whose precise form depends on the choice of the chiral copy. Remarkably, requiring the asymptotic symmetries to contain the full conformal group selects a very special set of boundary conditions that is labeled by a unique constant parameter, so that the algebra of the canonical generators is given by the direct sum of two copies of the Virasoro algebra with the standard central extension and U (1). This special set of boundary conditions makes the energy spectrum of electrically charged rotating black holes to be well-behaved.

  9. AL Amyloidosis and Agent Orange

    MedlinePlus

    ... for survivors' benefits . Research on AL amyloidosis and herbicides The Health and Medicine Division (formally known as ... to the compounds of interest found in the herbicide Agent Orange and AL amyloidosis." VA made a ...

  10. Modeling neuronal vulnerability in ALS.

    PubMed

    Roselli, Francesco; Caroni, Pico

    2014-08-20

    Using computational models of motor neuron ion fluxes, firing properties, and energy requirements, Le Masson et al. (2014) reveal how local imbalances in energy homeostasis may self-amplify and contribute to neurodegeneration in ALS.

  11. Improved Correction of IR Loss in Diffuse Shortwave Measurements: An ARM Value-Added Product

    SciTech Connect

    Younkin, K; Long, CN

    2003-11-01

    Simple single black detector pyranometers, such as the Eppley Precision Spectral Pyranometer (PSP) used by the Atmospheric Radiation Measurement (ARM) Program, are known to lose energy via infrared (IR) emission to the sky. This is especially a problem when making clear-sky diffuse shortwave (SW) measurements, which are inherently of low magnitude and suffer the greatest IR loss. Dutton et al. (2001) proposed a technique using information from collocated pyrgeometers to help compensate for this IR loss. The technique uses an empirically derived relationship between the pyrgeometer detector data (and alternatively the detector data plus the difference between the pyrgeometer case and dome temperatures) and the nighttime pyranometer IR loss data. This relationship is then used to apply a correction to the diffuse SW data during daylight hours. We developed an ARM value-added product (VAP) called the SW DIFF CORR 1DUTT VAP to apply the Dutton et al. correction technique to ARM PSP diffuse SW measurements.

  12. Al Jazirah, Sudan

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Al Jazirah (also Gezira) is one of the 26 states of Sudan. The state lies between the Blue Nile and the White Nile in the east-central region of the country. It is a well populated area suitable for agriculture. The area was at the southern end of Nubia and little is known about its ancient history and only limited archaeological work has been conducted in this area. The region has benefited from the Gezira Scheme, a program to foster cotton farming begun in 1925. At that time the Sennar Dam and numerous irrigation canals were built. Al Jazirah became the Sudan's major agricultural region with more than 2.5 million acres (10,000 km) under cultivation. The initial development project was semi-private, but the government nationalized it in 1950. Cotton production increased in the 1970s but by the 1990s increased wheat production has supplanted a third of the land formerly seeded with cotton.

    The image was acquired December 25, 2006, covers an area of 56 x 36.4 km, and is located near 14.5 degrees north latitude, 33.1 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  13. The AD 365 earthquake: high resolution tsunami inundation for Crete and full scale simulation exercise

    NASA Astrophysics Data System (ADS)

    Kalligeris, N.; Flouri, E.; Okal, E.; Synolakis, C.

    2012-04-01

    In the eastern Mediterranean, historical and archaeological records document major earthquake and tsunami events in the past 2000 year (Ambraseys and Synolakis, 2010). The 1200km long Hellenic Arc has allegedly caused the strongest reported earthquakes and tsunamis in the region. Among them, the AD 365 and AD 1303 tsunamis have been extensively documented. They are likely due to ruptures of the Central and Eastern segments of the Hellenic Arc, respectively. Both events had widespread impact due to ground shaking, and e triggered tsunami waves that reportedly affected the entire eastern Mediterranean. The seismic mechanism of the AD 365 earthquake, located in western Crete, has been recently assigned a magnitude ranging from 8.3 to 8.5 by Shaw et al., (2008), using historical, sedimentological, geomorphic and archaeological evidence. Shaw et al (2008) have inferred that such large earthquakes occur in the Arc every 600 to 800 years, with the last known the AD 1303 event. We report on a full-scale simulation exercise that took place in Crete on 24-25 October 2011, based on a scenario sufficiently large to overwhelm the emergency response capability of Greece and necessitating the invocation of the Monitoring and Information Centre (MIC) of the EU and triggering help from other nations . A repeat of the 365 A.D. earthquake would likely overwhelm the civil defense capacities of Greece. Immediately following the rupture initiation it will cause substantial damage even to well-designed reinforced concrete structures in Crete. Minutes after initiation, the tsunami generated by the rapid displacement of the ocean floor would strike nearby coastal areas, inundating great distances in areas of low topography. The objective of the exercise was to help managers plan search and rescue operations, identify measures useful for inclusion in the coastal resiliency index of Ewing and Synolakis (2011). For the scenario design, the tsunami hazard for the AD 365 event was assessed for

  14. High-performance Ni3Al synthesized from composite powders

    NASA Astrophysics Data System (ADS)

    Chiou, Wen-Chih; Hu, Chen-Ti

    1994-05-01

    Specimens of Ni3Al + B of high density (>99.3 Pct RD) and relatively large dimension have been synthesized from composite powders through processes of replacing plating and electroless Ni-B plating on Al powder, sintering, and thermal-mechanical treatment. The uniformly coated Ni layer over fine Al or Ni core particles constituting these coating/core composite powders has advantages such as better resistance to oxidation relative to pure Al powder, a greater green density as a compacted powder than prealloyed powder, the possibility of atomically added B to the material by careful choice of a suitable plating solution, and avoidance of the expensive powder metallurgy (PM) equipment such as a hot isostatic press (HIP), hot press (HP), etc. The final Ni3Al + B product is made from Ni-B-Al and Ni-B-Ni mixed composite powders by means of traditional PM processes such as compacting, sintering, rolling, and annealing, and therefore, the dimensions of the product are not constrained by the capacity of an HIP or HP. The properties of Ni3Al composite powder metallurgy (CPM) specimens tested at room temperature have been obtained, and comparison with previous reports is conducted. A tensile elongation of about 16 Pct at room temperature was attained.

  15. Massless Lüscher terms and the limitations of the AdS3 asymptotic Bethe ansatz

    NASA Astrophysics Data System (ADS)

    Abbott, Michael C.; Aniceto, Inês

    2016-05-01

    In AdS5/CFT4 integrability the Bethe ansatz gives the spectrum of long strings, accurate up to exponentially small corrections. This is no longer true in three-dimensional anti-de Sitter (AdS3 ) space, as we demonstrate here by studying Lüscher F-terms with a massless particle running in the loop. We apply this to the classic test of Hernández and López, in which the s u (2 ) sector Bethe equations (including the one-loop dressing phase) should match the semiclassical string theory result for a circular spinning string. These calculations do not agree in AdS3×S3×T4 , and we show that the sum of all massless Lüscher F-terms can reproduce the difference.

  16. Fermions Tunnelling from Black String and Kerr AdS Black Hole with Consideration of Quantum Gravity

    NASA Astrophysics Data System (ADS)

    Li, Zhong-hua; Zhang, Li-mei

    2016-01-01

    In this paper, using the Hamilton-Jacobi Ansatz, we discuss the tunnelling of fermions when effects of quantum gravity are taken into account. We investigate two cases, black string and Kerr AdS black hole. For black string, the uncharged and un-rotating case, we find that the correction of Hawking temperature is only affected by the mass of emitted fermions and the quantum gravitational corrections slow down the increases of the temperature, which naturally leads to remnants left in the evaporation. For another case, the Kerr AdS black hole, we find that the quantum gravitational corrections are not only determined by the mass of the emitted fermions but also affected by the rotating properties of the AdS black hole. So with consideration of the quantum gravity corrections, an offset around the standard temperature always exists.

  17. The effects of concentrate added to pineapple (Ananas comosus Linn. Mer.) waste silage in differing ratios to form complete diets, on digestion, excretion of urinary purine derivatives and blood metabolites in growing, male, Thai swamp buffaloes.

    PubMed

    Jetana, T; Suthikrai, W; Usawang, S; Vongpipatana, C; Sophon, S; Liang, J B

    2009-04-01

    Four, male, growing Thai swamp buffaloes (197 +/- 5.3 kg and all 1 year old) were used to evaluate the effects of concentrate added to pineapple waste silage in differing ratios, to form a complete diet, studying in vivo digestion, the rate of passage, microbial protein synthesis and blood metabolites. Animals were fed ad libitum with 4 diets, using four combinations of pineapple waste silage (P) and concentrate (C), in the proportions (on a dry matter basis) of 0.8:0.2 (P80:C20), 0.6:0.4 (P60:C40), 0.4:0.6 (P40:C60) and 0.2:0.8 (P20:C80). The results showed that the intakes of dry matter (DM), organic matter (OM), nitrogen (N), the N-balance, urinary purine derivatives (PD) excretion, the ratios of allantoin to creatinine (CR), PD to CR, the plasma urea-N (PUN) and insulin increased in the animals, but the intake of neutral detergent fiber (NDF), the coefficient of whole tract, apparent digestibility of NDF, the transit time (TT) and the mean retention time (TMRT) decreased, when the proportion of concentrate in the diet increased. This study indicated that the proportion of P40:C60 in the diet produced the best efficiency of urinary PD excretion (mmol) per digestible OM intake (kg DOMI).

  18. Supersymmetric partition functions in the AdS/CFT conjecture

    NASA Astrophysics Data System (ADS)

    Raju, Suvrat

    We study supersymmetric partition functions in several versions of the AdS/CFT correspondence. We present an Index for superconformal field theories in d = 3, 4, 5, 6. This captures all information about the spectrum that is protected, under continuous deformations of the theory, purely by group theory. We compute our Index in N = 4 SYM at weak coupling using gauge theory and at strong coupling using supergravity and find perfect agreement at large N. We also compute this Index for supergravity on AdS4 x S7 and AdS7 x S4 and for the recently constructed Chern Simons matter theories. We count 1/16 BPS states in the free gauge theory and find qualitative agreement with the entropy of big black holes in AdS5. We note that the near horizon geometry of some small supersymmetric black holes is an extremal BTZ black holes fibered on a compact base and propose a possible explanation for this, based on giant gravitons. We also find the partition function of the chiral ring of the N = 4 SYM theory at finite coupling and finite N. Turning to AdS3, we study the low energy 1/4 and 1/2 BPS partition functions by finding all classical supersymmetric probe brane solutions of string theory on this background. If the background BNS field and theta angle vanish, AdS3 x S 3 x T4/K3 supports supersymmetric probes: D1 branes, D5 branes and bound states of D5 and D1 branes. In global AdS, upon quantization, these solutions give rise to states in discrete representations of the SL(2,R) WZW model on AdS 3. We conclude that (a) the 1/4 BPS partition function jumps if we turn on a theta angle or NS-NS field (b) generic 1/2 BPS states are protected. We successfully compare our 1/2 BPS partition function with that of the symmetric product. We also discuss puzzles, and their possible resolutions, in reproducing the elliptic genus of the symmetric product. Finally, we comment on the spectrum of particles in the theory of gravity dual to non-supersymmetric Yang Mills theory on S3 x time.

  19. Want Ads, Job Skills, and Curriculum: A Survey of 1998 Chemistry Help-Wanted Ads

    NASA Astrophysics Data System (ADS)

    Headrick, Kurt L.

    2001-09-01

    Employer surveys are useful checks on how well we are preparing students for the working world. Employer surveys are also useful because they put curriculum deficiencies into terms that are readily understood; they can thus be a catalyst for curriculum reform. This study classified 2035 chemistry jobs advertized in newspapers across the USA in the fall of 1998 according to job type, employment sector, industry, type of chemistry principally involved, and academic background and experience desired. Job ads were also searched for keywords denoting a broad range of instrumentation and techniques, personality traits, and general work skills and experience. The total of 7872 keywords, an average of 3.9 per job, indicates that employers are looking for more than just a B.S. in chemistry.

  20. Chaos in classical string dynamics in γ ˆ deformed AdS5 × T1,1

    NASA Astrophysics Data System (ADS)

    Panigrahi, Kamal L.; Samal, Manoranjan

    2016-10-01

    We consider a circular string in γ ˆ deformed AdS5 ×T 1 , 1 which is localized in the center of AdS5 and winds around the two circles of deformed T 1 , 1. We observe chaos in the phase space of the circular string implying non-integrability of string dynamics. The chaotic behaviour in phase space is controlled by energy as well as the deforming parameter γ ˆ . We further show that the point like object exhibits non-chaotic behaviour. Finally we calculate the Lyapunov exponent for both extended and point like object in support of our first result.

  1. Stable p-branes in Chern-Simons AdS supergravities

    SciTech Connect

    Edelstein, Jose D.; Garbarz, Alan; Miskovic, Olivera; Zanelli, Jorge

    2010-08-15

    We construct static codimension-two branes in any odd dimension D, with a negative cosmological constant, and show that they are exact solutions of Chern-Simons (super)gravity theory for (super)AdS{sub D} coupled to external sources. The stability of these solutions is analyzed by counting the number of preserved supersymmetries. It is shown that static massive (D-3)-branes are unstable unless some suitable gauge fields are added and the brane is extremal. In particular, in three dimensions, a 0-brane is recognized as the negative mass counterpart of the Banados-Teitelboim-Zanelli black hole. For these 0-branes, we write explicitly magnetically charged Bogomol'nyi-Prasad-Sommerfield states with various numbers of preserved supersymmetries within the OSp(p|2)xOSp(q|2) supergroups. In five dimensions, we prove that stable 2-branes with magnetic charge always exist for the generic supergroup SU(2,4|N), where N{ne}4. For the special case N=4, in which Chern-Simons supergravity requires the addition of a nontrivial gauge field configuration in order to preserve the maximal number of degrees of freedom, we show for two different static 2-branes that they are Bogomol'nyi-Prasad-Sommerfield states (one of which is the ground state), and from the corresponding algebra of charges we show that the energy is bounded from below. In higher dimensions, our results admit a straightforward generalization, although there are presumably more solutions corresponding to different intersections of the elementary objects.

  2. On conserved charges and thermodynamics of the AdS4 dyonic black hole

    NASA Astrophysics Data System (ADS)

    Cárdenas, Marcela; Fuentealba, Oscar; Matulich, Javier

    2016-05-01

    We consider four-dimensional gravity in the presence of a dilatonic scalar field and an Abelian gauge field. This theory corresponds to the bosonic sector of a Kaluza-Klein reduction of eleven-dimensional supergravity which induces a specific self-interacting potential for the scalar field. We compute the conserved charges and carry out the thermodynamics of an anti-de Sitter (AdS) dyonic black hole solution that was proposed recently. The charges coming from symmetries of the action are computed using the Regge-Teitelboim Hamiltonian approach. They correspond to the mass, which acquires contributions from the scalar field, and the electric charge. We introduce integrability conditions because the scalar field leads to non-integrable terms in the variation of the mass. These conditions are generically solved by introducing boundary conditions that relate the leading and subleading terms of the scalar field fall-off. The Hamiltonian Euclidean action, computed in the grand canonical ensemble, is obtained by demanding the action to have an extremum. Its value is given by a radial boundary term plus an additional polar angle boundary term due to the presence of a magnetic monopole. Remarkably, the magnetic charge can be identified from the variation of the additional polar angle boundary term, confirming that the first law of black hole thermodynamics is a consequence of having a well-defined and finite Hamiltonian action principle, even if the charge does not come from a symmetry of the action. The temperature and electrostatic potential are determined by demanding regularity of the black hole solution, whereas the value of the magnetic potential is determined by the variation of the additional polar angle boundary term. Consequently, the first law of black hole thermodynamics is identically satisfied by construction.

  3. ALS Performance Summary - Update

    SciTech Connect

    Waters, A M; Brown, W D; Martz, Jr., H E

    2004-09-30

    High Energy Density Physics (HEDP) experiments play an important role in corroborating the improved physics codes that underlie LLNL's Stockpile Stewardship mission. Conducting these experiments, whether on the National Ignition Facility (NIF) or another national facility such as Omega, will require not only improvement in the diagnostics for measuring the experiment, but also detailed knowledge of the as-built target components and assemblies themselves. To assist in this effort, a defined set of well-known reference standards designed to represent a range of HEDP targets have been built and are being used to quantify the performance of different characterization techniques [Hibbard, et al. 2004]. Without the critical step of using reference standards for qualifying characterization tools there can be no verification of either commercial or internally-developed characterization techniques and thus an uncertainty in the input to the physics code models would exist.

  4. Stellar survivor from explosion in 1572 AD

    NASA Astrophysics Data System (ADS)

    2004-10-01

    burned-out 'white dwarf' star. The normal star spills material onto the dwarf, eventually triggering an explosion. The results of this research, led by Pilar Ruiz-Lapuente of the University of Barcelona, Spain, are published in the 28 October issue of the British science journal Nature. "There was no previous evidence pointing to any specific kind of companion star out of the many that had been proposed. Here we have identified a clear path: the feeding star is similar to our sun, but slightly older," said Ruiz-Lapuente. "The high speed of the star called our attention to it," she added. Type Ia supernovae are used to measure the history of the expansion rate of the Universe and so are fundamental in helping astronomers understand the behaviour of 'dark energy', an unknown force that is accelerating the expansion of the Universe. Finding evidence to confirm the theory as to how Type Ia supernovae explode is critical to assuring astronomers that the objects can be better understood as reliable calibrators of the expansion of space. Although today's astronomers are looking at this event 432 years too late, they were still able to see a star rushing away from the location of the explosion (which is now enveloped in a vast bubble of hot gas called 'Tycho's Supernova Remnant'). The runaway star and its surroundings have been studied with a variety of telescopes for the past seven years. The NASA/ESA Hubble Space Telescope played a key role in the process by measuring the star's motion against the sky background precisely. The star is breaking the speed limit for that particular region of the Milky Way Galaxy by moving three times faster than the surrounding stars. When the system was disrupted by the white dwarf's explosion, the companion star went hurtling off into space, like a stone thrown by a sling, retaining the velocity of its orbital motion. However there are alternative explanations for this motion. It could be falling into the region from the galactic halo that

  5. Value-Added Results for Public Virtual Schools in California

    ERIC Educational Resources Information Center

    Ford, Richard; Rice, Kerry

    2015-01-01

    The objective of this paper is to present value-added calculation methods that were applied to determine whether online schools performed at the same or different levels relative to standardized testing. This study includes information on how we approached our value added model development and the results for 32 online public high schools in…

  6. Is School Value Added Indicative of Principal Quality?

    ERIC Educational Resources Information Center

    Chiang, Hanley; Lipscomb, Stephen; Gill, Brian

    2016-01-01

    States across the country are developing systems for evaluating school principals on the basis of student achievement growth. A common approach is to hold principals accountable for the value added of their schools--that is, schools' contributions to student achievement growth. In theory, school value added can reflect not only principals'…

  7. Exogenous Variables and Value-Added Assessments: A Fatal Flaw

    ERIC Educational Resources Information Center

    Berliner, David C.

    2014-01-01

    Background: There has been rapid growth in value-added assessment of teachers to meet the widely supported policy goal of identifying the most effective and the most ineffective teachers in a school system. The former group is to be rewarded while the latter group is to be helped or fired for their poor performance. But, value-added approaches to…

  8. Clear Away the Smoke and Mirrors of Value-Added

    ERIC Educational Resources Information Center

    Harris, Douglas N.

    2010-01-01

    Current value-added models for teacher accountability are better than models based only on student achievement, but they have their weakness. They are subject to systematic and random error, as are all measures, and there are concerns about the tests used for the measurements. However, value-added models are better than the alternatives at the…

  9. Assured Information Sharing for Ad-Hoc Collaboration

    ERIC Educational Resources Information Center

    Jin, Jing

    2009-01-01

    Collaborative information sharing tends to be highly dynamic and often ad hoc among organizations. The dynamic natures and sharing patterns in ad-hoc collaboration impose a need for a comprehensive and flexible approach to reflecting and coping with the unique access control requirements associated with the environment. This dissertation…

  10. 33 CFR 157.35 - Ballast added to cargo tanks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Ballast added to cargo tanks. 157.35 Section 157.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.35 Ballast added to cargo tanks. The master of a tank vessel...

  11. 33 CFR 157.35 - Ballast added to cargo tanks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ballast added to cargo tanks. 157.35 Section 157.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.35 Ballast added to cargo tanks. The master of a tank vessel...

  12. 27 CFR 19.384 - Adding denaturants to spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Adding denaturants to spirits. 19.384 Section 19.384 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE... of Articles Rules for Denaturing Spirits and Testing Denaturants § 19.384 Adding denaturants...

  13. 48 CFR 453.303-838 - Purchase Order (AD-838).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Purchase Order (AD-838). 453.303-838 Section 453.303-838 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE CLAUSES AND FORMS FORMS Illustrations of Forms 453.303-838 Purchase Order (AD-838)....

  14. Value Added Methods: Moving from Univariate to Multivariate Criteria

    ERIC Educational Resources Information Center

    Newman, David; Newman, Isadore; Ridenour, Carolyn; Morales, Jennifer

    2014-01-01

    The authors describe five value-added methods (VAM) used in school assessment as the backdrop to their main thesis. Then they review the assumptions underlying measurement and evaluation, the foundation of all assessment systems, including value-added. They discuss the traditional criterion variable used in VAM: a standardized test score. Next,…

  15. 48 CFR 453.303-700 - Procurement Request (AD-700).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Procurement Request (AD-700). 453.303-700 Section 453.303-700 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE CLAUSES AND FORMS FORMS Illustrations of Forms 453.303-700 Procurement Request (AD-700)....

  16. Secure ADS-B authentication system and method

    NASA Technical Reports Server (NTRS)

    Viggiano, Marc J (Inventor); Valovage, Edward M (Inventor); Samuelson, Kenneth B (Inventor); Hall, Dana L (Inventor)

    2010-01-01

    A secure system for authenticating the identity of ADS-B systems, including: an authenticator, including a unique id generator and a transmitter transmitting the unique id to one or more ADS-B transmitters; one or more ADS-B transmitters, including a receiver receiving the unique id, one or more secure processing stages merging the unique id with the ADS-B transmitter's identification, data and secret key and generating a secure code identification and a transmitter transmitting a response containing the secure code and ADSB transmitter's data to the authenticator; the authenticator including means for independently determining each ADS-B transmitter's secret key, a receiver receiving each ADS-B transmitter's response, one or more secure processing stages merging the unique id, ADS-B transmitter's identification and data and generating a secure code, and comparison processing comparing the authenticator-generated secure code and the ADS-B transmitter-generated secure code and providing an authentication signal based on the comparison result.

  17. 2 CFR 200.470 - Taxes (including Value Added Tax).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2 Grants and Agreements 1 2014-01-01 2014-01-01 false Taxes (including Value Added Tax). 200.470... Cost § 200.470 Taxes (including Value Added Tax). (a) For states, local governments and Indian tribes: (1) Taxes that a governmental unit is legally required to pay are allowable, except for...

  18. Beyond the Job Ad: Employers and Library Instruction

    ERIC Educational Resources Information Center

    Hall, Russell A.

    2013-01-01

    Many content analyses of job ads have revealed the skills and experience needed in academic library jobs and show that library instruction is an important job duty. This study moves beyond the content of the job ads and surveys the employers themselves (in the person of the supervisor). The survey revealed that supervisors highly value library…

  19. 17 CFR 240.17Ad-8 - Securities position listings.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... fee designed to recover the reasonable costs of providing the securities position listing to the... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Securities position listings. 240.17Ad-8 Section 240.17Ad-8 Commodity and Securities Exchanges SECURITIES AND EXCHANGE...

  20. Healthy Skepticism's new AdWatch: understanding drug promotion.

    PubMed

    Mansfield, Peter R

    The AdWatch section of the Healthy Skepticism website (http://www.healthyskepticism.org/adwatch.asp) aims to improve medical decision-making by illuminating the techniques used in drug advertising. AdWatch draws on 20 years of dialogue about drug promotion plus ideas from many disciplines, especially logic, psychology and marketing. PMID:14636142

  1. How Does Value-Added Data Affect Teachers?

    ERIC Educational Resources Information Center

    Jennings, Jennifer L.; Pallas, Aaron M.

    2016-01-01

    Teacher evaluation systems can have high stakes for individual teachers, and it's important to ask how new evaluation models--including value-added measures--serve teachers as they strive to improve their practice. The authors interviewed teachers at a high-performing New York City school about their reactions to their value-added scores and…

  2. Alcohol as Good Food: Adolescents' Responses to Liqueur Ads.

    ERIC Educational Resources Information Center

    Neuendorf, Kimberly A.; Pearlman, Reid A.

    Examining responses to print alcohol advertisements, a study questioned whether alcohol advertisers distinguish between "hard" and "soft" liquors (e.g. wine coolers and liqueurs). Subjects, 102 junior and senior high school students in a major metropolitan area, were asked to examine one set of three ads--either hard liquor ads or soft liquor ads…

  3. 48 CFR 453.303-838 - Purchase Order (AD-838).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Purchase Order (AD-838). 453.303-838 Section 453.303-838 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE CLAUSES AND FORMS FORMS Illustrations of Forms 453.303-838 Purchase Order (AD-838)....

  4. 17 CFR 240.17Ad-3 - Limitations on expansion.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Limitations on expansion. 240.17Ad-3 Section 240.17Ad-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... expansion. (a) Any registered transfer agent which is required to file any notice pursuant to §...

  5. 17 CFR 240.17Ad-3 - Limitations on expansion.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 3 2012-04-01 2012-04-01 false Limitations on expansion. 240.17Ad-3 Section 240.17Ad-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... expansion. (a) Any registered transfer agent which is required to file any notice pursuant to §...

  6. 17 CFR 240.17Ad-3 - Limitations on expansion.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Limitations on expansion. 240.17Ad-3 Section 240.17Ad-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... expansion. (a) Any registered transfer agent which is required to file any notice pursuant to §...

  7. 17 CFR 240.17Ad-3 - Limitations on expansion.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Limitations on expansion. 240.17Ad-3 Section 240.17Ad-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... Limitations on expansion. (a) Any registered transfer agent which is required to file any notice pursuant...

  8. 17 CFR 240.17Ad-3 - Limitations on expansion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Limitations on expansion. 240.17Ad-3 Section 240.17Ad-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION... expansion. (a) Any registered transfer agent which is required to file any notice pursuant to §...

  9. Public-key management in mobile ad hoc networks

    NASA Astrophysics Data System (ADS)

    Lin, Haifeng; Jiang, Anna; Bai, Di; Liu, Yunfei

    A mobile ad hoc network is a new type of wireless networking paradigm which, in general, consists of solely mobile hosts and dispenses with infrastructure. One main challenge in design of mobile ad hoc networks is the vulnerability to security attacks. Without physical boundaries, a mobile ad hoc network faces many more security threats than a wired network does. Therefore the security of mobile ad hoc networks is one of the major research interests in wireless communications. In contrast with conventional networks, public key management protocols of mobile ad hoc networks do not based on infrastructures, where we can use trusted third parties or centralized servers for key management. This is because that the topology of mobile ad hoc networks is unknown due to link and node failures and to node mobility. For these factors, traditional key management solutions which require on-line trusted authorities or certificate authorities are not suitable for securing mobile ad hoc networks. In this report, we first review some existed public-key management protocols for mobile ad hoc networks and after that we propose a fully distributed public -key management model which does not need the third trusted authority.

  10. Superconducting A/D converter using latching comparators

    SciTech Connect

    Hamilton, C.A.; Kautz, R.L.; Loyld, F.L.

    1985-03-01

    This paper describes the design and performance of a six-bit A/D converter using fast edge latching comparators. Simulations predicting conversion times of 100 ps and 100 MHz signal bandwidth are verified experimentally. The addition of a superconducting track/hold circuit in front of the A/D converter is expected to substantially improve the signal bandwidth.

  11. Visuospatial memory in healthy elderly, AD and MCI: a review.

    PubMed

    Iachini, Ina; Iavarone, Alessandro; Senese, Vincenzo Paolo; Ruotolo, Francesco; Ruggiero, Gennaro

    2009-03-01

    In the literature it is commonly reported that several spatial abilities decline with normal aging, even though such a decline is not uniform. So far, it is not yet clear which spatial components present a normal age-related decline, which ones are preserved and at what point the deficit is so severe to represent an index of mild cognitive impairment (MCI) or a symptom of potential degenerative progression as in the early-stage Alzheimer's disease (AD). In particular, AD (from early onset) is characterised by impairments in constructive abilities, visuospatial intelligence, spatial short-term memory deficits, and disorders of spatial orientation (topographical disorientation). MCI indicates a condition, generally affecting older individuals, characterized by cognitive deficits including memory and/or non memory impairments and at high risk of progression to dementia. Three MCI subgroups have been distinguished and a very high risk of developing AD is associated to the amnestic MCI subtypes. Further, recent studies have suggested that the allocentric component of spatial memory might be taken as predictor of AD from MCI. Given the frequency of visuospatial deficits in early-stage AD, evaluation of visuospatial processes is a promising approach to find predictive markers of AD. Here we report a review of the literature exploring specific visuospatial components in normal aging, MCI, and AD. In this way we could shed some light on the role of these components in the progression from MCI to AD and pave the way for future studies.

  12. Analysis of Added Value of Subscores with Respect to Classification

    ERIC Educational Resources Information Center

    Sinharay, Sandip

    2014-01-01

    Brennan noted that users of test scores often want (indeed, demand) that subscores be reported, along with total test scores, for diagnostic purposes. Haberman suggested a method based on classical test theory (CTT) to determine if subscores have added value over the total score. One way to interpret the method is that a subscore has added value…

  13. 14 CFR 1203.903 - Ad hoc committees.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Ad hoc committees. 1203.903 Section 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson is...

  14. 14 CFR § 1203.903 - Ad hoc committees.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 5 2014-01-01 2014-01-01 false Ad hoc committees. § 1203.903 Section § 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson...

  15. 14 CFR 1203.903 - Ad hoc committees.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Ad hoc committees. 1203.903 Section 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson is...

  16. 14 CFR 1203.903 - Ad hoc committees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Ad hoc committees. 1203.903 Section 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson is...

  17. 14 CFR 1203.903 - Ad hoc committees.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Ad hoc committees. 1203.903 Section 1203.903 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION INFORMATION SECURITY PROGRAM NASA Information Security Program Committee § 1203.903 Ad hoc committees. The Chairperson is authorized...

  18. Epoxy Composites with Added Aluminum with Binary Particle Size Distribution for Enhanced Dielectric Properties and Thermal Conductivity

    NASA Astrophysics Data System (ADS)

    Sui, Xuezhen; Zhou, Wenying; Dong, Lina; Wang, Zijun; Wu, Peng; Zuo, Jing; Cai, Huiwu; Liu, Xiangrong

    2016-08-01

    Three kinds of hybrid aluminum (Al) particles with binary particle size distribution, i.e., [2 μm/50 μm], [2 μm/18 μm] and [18 μm/50 μm], were added in epoxy (EP) to prepare hybrid Al/EP composites with enhanced dielectric properties and thermal conductivity for embedded capacitor applications. The dielectric permittivity, dissipation factor, and thermal conductivity of three types of hybrid Al/EP composites were investigated as a function of relative volume fraction of smaller-size Al of hybrid Al particles (V s) at a total filler content of 60 wt.%, respectively. The results indicate that dielectric permittivity and thermal conductivity of the hybrid Al/EP mainly depend on two factors, such as the type of hybrid filler and the V s. The maximum dielectric permittivity of 48 appears at V s = V 18μm/V (18μm+50μm) = 35%. While, the above two factors have a negligible influence on the dissipation factor, which is as low as 0.022. The highest thermal conductivity of 1.28 W/m K is obtained at V s = V 18μm/V (18μm+50μm) = 50%. The maximum thermal conductivity for three hybrid systems shifts towards lower V s with decreasing the size ratio of a larger Al to a smaller one.

  19. Epoxy Composites with Added Aluminum with Binary Particle Size Distribution for Enhanced Dielectric Properties and Thermal Conductivity

    NASA Astrophysics Data System (ADS)

    Sui, Xuezhen; Zhou, Wenying; Dong, Lina; Wang, Zijun; Wu, Peng; Zuo, Jing; Cai, Huiwu; Liu, Xiangrong

    2016-11-01

    Three kinds of hybrid aluminum (Al) particles with binary particle size distribution, i.e., [2 μm/50 μm], [2 μm/18 μm] and [18 μm/50 μm], were added in epoxy (EP) to prepare hybrid Al/EP composites with enhanced dielectric properties and thermal conductivity for embedded capacitor applications. The dielectric permittivity, dissipation factor, and thermal conductivity of three types of hybrid Al/EP composites were investigated as a function of relative volume fraction of smaller-size Al of hybrid Al particles ( V s) at a total filler content of 60 wt.%, respectively. The results indicate that dielectric permittivity and thermal conductivity of the hybrid Al/EP mainly depend on two factors, such as the type of hybrid filler and the V s. The maximum dielectric permittivity of 48 appears at V s = V 18 μm/ V (18 μm+50 μm) = 35%. While, the above two factors have a negligible influence on the dissipation factor, which is as low as 0.022. The highest thermal conductivity of 1.28 W/m K is obtained at V s = V 18 μm/ V (18 μm+50 μm) = 50%. The maximum thermal conductivity for three hybrid systems shifts towards lower V s with decreasing the size ratio of a larger Al to a smaller one.

  20. Cost-effective advertising through TV and newspaper "banner" ads.

    PubMed

    Gombeski, William R; Taylor, Jan; Krauss, Katie; Medeiros, Clayton

    2003-01-01

    Banner ads, small strip ads in newspapers used to specifically promote an information piece, were introduced into one newspaper in the Connecticut market in 1999 by Yale-New Haven Hospital (YNHH). Based on their success, the concept was expanded to six additional newspapers in late 2000 and to TV in the summer of 2001. Between 2000-2002, even as the overall marketing/advertising budget declined 30%, switching advertising dollars from image/display ads to banner ads resulted in consumer awareness of YNHH increasing from 29% to 42%. Perception of YNHH as "the advanced medicine" hospital grew from 22% to 40% during the same period. The specific strategic and operational actions generated since the implementation of the program are detailed and the advantages and disadvantages of this banner advertising approach are discussed. Banner ads may offer an alternative approach for organizations to advertise their products and programs.