Midbrain response to milkshake correlates with ad libitum milkshake intake in the absence of hunger.

PubMed

Nolan-Poupart, Sarah; Veldhuizen, Maria G; Geha, Paul; Small, Dana M

2013-01-01

There is now widespread agreement that individual variation in the neural circuits representing the reinforcing properties of foods may be associated with risk for overeating and obesity. What is currently unknown is how and whether brain response to a food is related to immediate subsequent intake of that food. Here we used functional magnetic resonance imaging (fMRI) to test whether response to a palatable milkshake is associated with subsequent ad libitum milkshake consumption. We predicted that enhanced responses in key reward regions (insula, striatum, midbrain, medial orbitofrontal cortex) and decreased responses in regions implicated in self-control (lateral prefrontal and lateral orbitofrontal cortex) would be associated with greater intake. We found a significant positive association between response to milkshake in the periaqueductal gray region of the midbrain and ad libitum milkshake intake. Although strong bilateral insular responses were observed during consumption of the milkshake this response did not correlate with subsequent intake. The associations observed in the midbrain and orbitofrontal cortex were uninfluenced by ratings of hunger, which were near neutral. We conclude that midbrain response to a palatable food is related to eating in the absence of hunger. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of salt intensity on ad libitum intake of tomato soup similar in palatability and on salt preference after consumption.

PubMed

Bolhuis, Dieuwerke P; Lakemond, Catriona M M; de Wijk, Rene A; Luning, Pieternel A; de Graaf, Cees

2010-11-01

Sensory properties of food play an important role in satiation. Studies on the effect of taste intensity on satiation show conflicting results. This may be due to the notion that in these studies taste intensity and palatability were confounded. The objective of this study was to investigate the effect of salt intensity of tomato soup on ad libitum intake (satiation), while controlling for palatability on an individual basis. Forty-eight subjects consumed both a low-salt (LS) and high-salt (HS) soup ad libitum from a self-refilling bowl. The results showed no difference between LS and HS soup in ad libitum intake, eating rate, changes in appetite ratings, and changes in hedonic ratings after intake. After intake of HS soup, LS soup was perceived as more bland than before intake of HS soup. After intake of LS soup, HS soup was perceived as more salt intense than before intake of LS soup. In conclusion, this study found no effect of salt intensity on satiation of tomato soups that were similar in palatability. During consumption, subjects adapted quickly to the exposed salt intensity as contrasting salt intensities were rated further from the ideal salt intensity and therefore perceived as less pleasant after consumption.

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Influence of a Mouthpiece-Based Topography Measurement Device on Electronic Cigarette User's Plasma Nicotine Concentration, Heart Rate, and Subjective Effects Under Directed and Ad Libitum Use Conditions.

PubMed

Spindle, Tory R; Hiler, Marzena M; Breland, Alison B; Karaoghlanian, Nareg V; Shihadeh, Alan L; Eissenberg, Thomas

2017-04-01

Electronic cigarettes e-cigarettes aerosolize a liquid solution often containing nicotine. e-cigarette nicotine delivery may be influenced by user puffing behaviors ("puff topography"). E-cigarette puff topography can be recorded using mouthpiece-based computerized systems. The present study sought to examine the extent to which these systems influence e-cigarette nicotine delivery and other e-cigarette associated acute effects under ad libitum use conditions. Plasma nicotine concentration, heart rate, and subjective effects were assessed in 29 experienced e-cigarette users using their preferred e-cigarette battery and liquid (≥12mg/mL nicotine) in two sessions differing only by the presence of a mouthpiece-based device. In both sessions, participants completed a directed e-cigarette use bout (10 puffs, 30-s interpuff interval) and a 90-min ad libitum bout. Puff topography was recorded in the session with the topography mouthpiece. Plasma nicotine, heart rate, and subjective effects, aside from "Did the e-cigarette Taste Good?" were independent of topography measurement (higher mean taste ratings were observed in the no topography condition). Mean (SEM) plasma nicotine concentration following the ad libitum bout was 34.3ng/mL (4.9) in the no topography condition and 35.7ng/mL (4.3) in the topography condition. Longer puff durations, longer interpuff intervals, and larger puff volumes were observed in the ad libitum relative to the directed bout. E-cigarette use significantly increased plasma nicotine concentration and heart rate while suppressing abstinence symptoms. These effects did not differ when a topography mouthpiece was present. Future studies using ad libitum e-cigarette use bouts would facilitate understanding of e-cigarette toxicant yield. No prior study has examined whether mouthpiece-based topography recording devices influence e-cigarette associated nicotine delivery, heart rate, or subjective effects under ad libitum conditions or assessed ad

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. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

Anterior cingulate taste activation predicts ad libitum intake of sweet and savory drinks in healthy, normal-weight men.

PubMed

Spetter, Maartje S; de Graaf, Cees; Viergever, Max A; Smeets, Paul A M

2012-04-01

After food consumption, the motivation to eat (wanting) decreases and associated brain reward responses change. Wanting-related brain responses and how these are affected by consumption of specific foods are ill documented. Moreover, the predictive value of food-induced brain responses for subsequent consumption has not been assessed. We aimed to determine the effects of consumption of sweet and savory foods on taste activation in the brain and to assess how far taste activation can predict subsequent ad libitum intake. Fifteen healthy men (age: 27 ± 2 y, BMI: 22.0 ± 1.5 kg/m2) participated in a randomized crossover trial. After a >3-h fast, participants were scanned with the use of functional MRI before and after consumption of a sweet or savory preload (0.35 L fruit or tomato juice) on two occasions. After the scans, the preload juice was consumed ad libitum. During scanning, participants tasted the juices and rated their pleasantness. Striatal taste activation decreased after juice consumption, independent of pleasantness. Sweet and savory taste activation were not differentially affected by consumption. Anterior cingulate taste activation predicted subsequent ad libitum intake of sweet (r = -0.78; P < 0.001(uncorrected)) as well as savory juice (r = -0.70; P < 0.001(uncorrected)). In conclusion, we showed how taste activation of brain reward areas changes following food consumption. These changes may be associated with the food's physiological relevance. Further, the results suggest that anterior cingulate taste activation reflects food-specific satiety. This extends our understanding of the representation of food specific-appetite in the brain and shows that neuroimaging may provide objective and more accurate measures of food motivation than self-report measures.

Trained humans can exercise safely in extreme dry heat when drinking water ad libitum.

PubMed

Nolte, Heinrich W; Noakes, Timothy D; Van Vuuren, Bernard

2011-09-01

Guidelines to establish safe environmental exercise conditions are partly based on thermal prescriptive zones. Yet there are reports of self-paced human athletic performances in extreme heat. Eighteen participants undertook a 25-km route march in a dry bulb temperature reaching 44.3°C. The mean (± s) age of the participants was 26.0 ± 3.7 years. Their mean ad libitum water intake was 1264 ± 229 mL · h(-1). Predicted sweat rate was 1789 ± 267 mL · h(-1). Despite an average body mass loss of 2.73 ± 0.98 kg, plasma osmolality and serum sodium concentration did not change significantly during exercise. Total body water fell 1.47 kg during exercise. However, change in body mass did not accurately predict changes in total body water as a 1:1 ratio. There was a significant relationship (negative slope) between post-exercise serum sodium concentration and changes in both body mass and percent total body water. There was no relationship between percent body mass loss and peak exercise core temperature (39 ± 0.9°C) or exercise time. We conclude that participants maintained plasma osmolality, serum sodium concentration, and safe core temperatures by (1) adopting a pacing strategy, (2) high rates of ad libitum water intake, and (3) by a small reduction in total body water to maintain serum sodium concentration. Our findings support the hypothesis that humans are the mammals with the greatest capacity for exercising in extreme heat.

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

Individual fluid plans versus ad libitum on hydration status in minor professional ice hockey players.

PubMed

Emerson, Dawn M; Torres-McGehee, Toni M; Emerson, Charles C; LaSalle, Teri L

2017-01-01

Despite exercising in cool environments, ice hockey players exhibit several dehydration risk factors. Individualized fluid plans (IFPs) are designed to mitigate dehydration by matching an individual's sweat loss in order to optimize physiological systems and performance. A randomized control trial was used to examine IFP versus ad libitum fluid ingestion on hydration in 11 male minor professional ice hockey players (mean age = 24.4 ± 2.6 years, height = 183.0 ± 4.6 cm, weight = 92.9 ± 7.8 kg). Following baseline measures over 2 practices, participants were randomly assigned to either control (CON) or intervention (INT) for 10 additional practices. CON participants were provided water and/or carbohydrate electrolyte beverage to drink ad libitum. INT participants were instructed to consume water and an electrolyte-enhanced carbohydrate electrolyte beverage to match sweat and sodium losses. Urine specific gravity, urine color, and percent body mass change characterized hydration status. Total fluid consumed during practice was assessed. INT consumed significantly more fluid than CON (1180.8 ± 579.0 ml vs. 788.6 ± 399.7 ml, p  = 0.002). However, CON participants replaced only 25.4 ± 12.9% of their fluid needs and INT 35.8 ± 17.5%. Mean percent body mass loss was not significantly different between groups and overall indicated minimal dehydration (<1.2% loss). Pre-practice urine specific gravity indicated CON and INT began hypohydrated (mean = 1.024 ± 0.007 and 1.024 ± 0.006, respectively) and experienced dehydration during practice (post = 1.026 ± 0.006 and 1.027 ± 0.005, respectively, p  < 0.001). Urine color increased pre- to post-practice for CON (5 ± 2 to 6 ± 1, p  < 0.001) and INT (5 ± 1 to 6 ± 1, p <  0.001). Participants consistently reported to practice hypohydrated. Ad libitum fluid intake was not significantly different than IFP on hydration status. Based on urine measures, both methods were

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

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

PubMed

Piaggi, Paolo; Thearle, Marie S; Krakoff, Jonathan; Votruba, Susanne B

2015-08-01

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. 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. One hundred seven healthy individuals (62 males/45 females, 84 Native Americans/23 whites; age 33 ± 8 y; body mass index 33 ± 8 kg/m(2); 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. 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. Higher 24-hour RQ (P < .001, partial R(2) = 16%) and EE (P = .01, partial R(2) = 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/m(2) or less (r = 0.44, P = .01). 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.

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

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

PubMed

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

2016-05-01

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. 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). 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 8.4 ng/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. 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. 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 combustion by heating tobacco at a much lower temperature

Alterations in energy balance from an exercise intervention with ad libitum food intake.

PubMed

Melzer, Katarina; Renaud, Anne; Zurbuchen, Stefanie; Tschopp, Céline; Lehmann, Jan; Malatesta, Davide; Ruch, Nicole; Schutz, Yves; Kayser, Bengt; Mäder, Urs

2016-01-01

Better understanding is needed regarding the effects of exercise alone, without any imposed dietary regimens, as a single tool for body-weight regulation. Thus, we evaluated the effects of an 8-week increase in activity energy expenditure (AEE) on ad libitum energy intake (EI), body mass and composition in healthy participants with baseline physical activity levels (PAL) in line with international recommendations. Forty-six male adults (BMI = 19·7-29·3 kg/m(2)) participated in an intervention group, and ten (BMI = 21·0-28·4 kg/m(2)) in a control group. Anthropometric measures, cardiorespiratory fitness, EI, AEE and exercise intensity were recorded at baseline and during the 1st, 5th and 8th intervention weeks, and movement was recorded throughout. Body composition was measured at the beginning and at the end of the study, and resting energy expenditure was measured after the study. The intervention group increased PAL from 1·74 (se 0·03) to 1·93 (se 0·03) (P < 0·0001) and cardiorespiratory fitness from 41·4 (se 0·9) to 45·7 (se 1·1) ml O2/kg per min (P = 0·001) while decreasing body mass (-1·36 (se 0·2) kg; P = 0·001) through adipose tissue mass loss (ATM) (-1·61 (se 0·2) kg; P = 0·0001) compared with baseline. The control group did not show any significant changes in activity, body mass or ATM. EI was unchanged in both groups. The results indicate that in normal-weight and overweight men, increasing PAL from 1·7 to 1·9 while keeping EI ad libitum over an 8-week period produces a prolonged negative energy balance. Replication using a longer period (and/or more intense increase in PAL) is needed to investigate if and at what body composition the increase in AEE is met by an equivalent increase in EI.

Utilization patterns and user characteristics of an ad libitum Internet weight loss program.

PubMed

Binks, Martin; van Mierlo, Trevor

2010-03-29

The Internet holds promise for the delivery of evidence-based weight loss treatment to underserved populations. However, most studies do not reflect the more naturalistic and common ad libitum, or freely at will, use of the Internet. Randomized clinical trials, for example, typically include at least some direct contact with participants and often have restrictive selection criteria. There is a paucity of research examining utilization patterns of online weight loss programs, particularly in the rapidly expanding direct-to-consumer arena. To examine self-reported characteristics (age, body mass index [BMI], gender), behaviors, and Internet site utilization patterns of a sample of users of a direct-to-consumer ad libitum Internet weight loss program. This study is based on analysis of archival data from the initial 15 weeks of an ongoing, free, evidence-based, direct-to-consumer Internet weight loss program, the Healthy Weight Center, which included standard information about nutrition, fitness, and behavioral strategies; monitoring tools; and moderated support group message boards. Participants encountered the program through self-directed Internet searches and anonymously registered to utilize the site. Self-reported user characteristics and electronically tracked utilization data were extracted from existing program data, compiled, and examined. Pearson correlations were computed to examine the association of program utilization with age and BMI. One-way analysis of variance (ANOVA) was used for gender comparisons. We examined data from the first 204 adult users of the program who were classified as either overweight (BMI 25 to < 30 kg/m(2)) or obese (BMI > or = 30 kg/m(2)). The mean age of participants was 42.0 years (SD 11.7), 81.9% (167/204) were women, and mean BMI was 32.01 kg/m(2) (SD 6.26). The percent of participants who used program tools was as follows: 13.7%, meal planner; 10.8%, nutrition lookup: 17.6%, activity log; 14.2%, journal; and 22.1%, weight

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

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.

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

PubMed

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

2016-02-01

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. 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. 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). 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 the appetite-stimulating hormone-acylated ghrelin during the afternoon

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.

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

Protection of total body water content and absence of hyperthermia despite 2% body mass loss ('voluntary dehydration') in soldiers drinking ad libitum during prolonged exercise in cool environmental conditions.

PubMed

Nolte, Heinrich W; Noakes, Timothy D; van Vuuren, Bernard

2011-11-01

The extent to which humans need to replace fluid losses during exercise remains contentious despite years of focused research. The primary objective was to evaluate ad libitum drinking on hydration status to determine whether body mass loss can be used as an accurate surrogate for changes in total body water (TBW) during exercise. Data were collected during a 14.6-km route march (wet bulb globe temperature of 14.1°C ). 18 subjects with an average age of 26 ± 2.5 (SD) years participated. Their mean ad libitum total fluid intake was 2.1 ± 1.4 litres during the exercise. Predicted sweat rate was 1.289 ± 0.530 l/h. There were no significant changes (p>0.05) in TBW, urine specific gravity or urine osmolality despite an average body mass loss (p<0.05) of 1.3 ± 0.45 kg during the march. Core temperature rose as a function of marching speed and was unrelated to the % change in body mass. This suggests that changes in mass do not accurately predict changes in TBW (r=-0.16) because either the body mass loss during exercise includes losses other than water or there is an endogenous body water source that is released during exercise not requiring replacement during exercise, or both. Ad libitum water replacement between 65% and 70% of sweat losses maintained safe levels of hydration during the experiment. The finding that TBW was protected by ad libitum drinking despite approximately 2% body mass loss suggests that the concept of 'voluntary dehydration' may require revision.

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.

Ad libitum Mediterranean and Low Fat Diets both Significantly Reduce Hepatic Steatosis: a Randomized Controlled Trial.

PubMed

Properzi, Catherine; O'Sullivan, Therese A; Sherriff, Jill L; Ching, Helena L; Jeffrey, Garry P; Buckley, Rachel F; Tibballs, Jonathan; MacQuillan, Gerry C; Garas, George; Adams, Leon A

2018-05-05

Although diet induced weight loss is first-line treatment for patients with non-alcoholic fatty liver disease (NAFLD), long-term maintenance is difficult. The optimal diet for either improvement in NAFLD or associated cardio-metabolic risk factors regardless of weight loss, is unknown. We examined the effect of two ad libitum isocaloric diets [Mediterranean (MD) or Low Fat (LF)] on hepatic steatosis and cardio-metabolic risk factors. Subjects with NAFLD were randomized to a 12-week blinded dietary intervention (MD vs LF). Hepatic steatosis was determined via magnetic resonance spectroscopy (MRS). From a total of 56 subjects enrolled, 49 subjects completed the intervention and 48 were included for analysis. During the intervention, subjects on the MD had significantly higher total and monounsaturated fat but lower carbohydrate and sodium intakes compared to LF subjects (p<0.01). At week 12, hepatic steatosis had reduced significantly in both groups (p<0.01) and there was no difference in liver fat reduction between the groups (p=0.32), with mean (SD) relative reductions of 25.0% (±25.3%) in LF and 32.4% (±25.5%) in MD. Liver enzymes also improved significantly in both groups. Weight loss was minimal and not different between groups [-1.6 (±2.1)kg in LF vs -2.1 (±2.5)kg in MD, (p=0.52)]. Within-group improvements in the Framingham risk score, total cholesterol, serum triglyceride, and HbA1c were observed in the MD (all p<0.05) but not with the LF diet. Adherence was higher for the MD compared to LF (88% vs. 64%, p=0.048). Ad libitum low fat and Mediterranean diets both improve hepatic steatosis to a similar degree. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

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.

Fluid, energy and nutrient recovery via ad libitum intake of different fluids and food.

PubMed

Campagnolo, Nadia; Iudakhina, Elizaveta; Irwin, Christopher; Schubert, Matthew; Cox, Gregory R; Leveritt, Michael; Desbrow, Ben

2017-03-15

This study compared the effects of ad libitum consumption of different beverages and foods on fluid retention and nutrient intake following exercise. Ten endurance trained males (mean±SD; Age=25.3±4.9years, VO 2 max=63.0±7.2mL·kg·min -1 ) performed four trials employing a counterbalanced, crossover design. Following 60min of exercise (matched for energy expenditure and fluid loss) participants consumed either water (W1 and W2), a sports drink (Powerade® (P)) or a milk-based liquid meal supplement (Sustagen Sport® (SS)) over a four hour recovery period. Additionally, participants had access to snack foods on two occasions within the first 2h of recovery on all trials. All beverages and food were consumed ad libitum. Total nutrient intake, urine volume, USG, body weight as well as subjective measures of gastrointestinal tolerance and thirst were obtained hourly. Plasma osmolality was measured pre, post, 1 and 4h after exercise. Total fluid volume ingested from food and beverages in W1 (2.28±0.42L) and P (2.82±0.80L) trials were significantly greater than SS (1.94±0.54L). Total urine output was not different between trials (W1=644±202mL, W2=602±352mL, P=879±751mL, SS=466±129mL). No significant differences in net body weight change was observed between trials (W1=0.01±0.28kg, W2=0.08±0.30kg, P=-0.02±0.24kg, SS=-0.05±0.24kg). Total energy intake was higher on P (10,179±1484kJ) and SS (10,577±2210kJ) compared to both water trials (W1=7826±888kJ, W2=7578±1112kJ). With the co-ingestion of food, fluid restoration following exercise is tightly regulated and not influenced by the choice of either water, a carbohydrate-electrolyte (sports drink) or a milk-based beverage. Copyright © 2017 Elsevier Inc. All rights reserved.

Use Behaviors, Dependence, and Nicotine Exposure Associated with Ad Libitum Cigar Smoking

PubMed Central

Claus, Eric D.; Moeller, Benjamin C.; Harbour, Darlene; Kuehl, Philip J.; McGuire, Michael; Vivar, Juan C.; Schroeder, Megan J.

2018-01-01

Objectives To examine factors important to cigar smoking and subsequent nicotine exposure, we evaluated the impact of cigar type, cigarette smoking history, and inhalation behaviors on nicotine dependence, smoking topography, and biomarkers of exposure in current exclusive cigar smokers. Methods Adult, exclusive cigar smokers (N = 77) were recruited based on cigar type, cigarette smoking history, and self-reported inhalation behaviors. Participants smoked their own brand product ad libitum for up to one hour; dependence symptoms, smoking topography, and biomarkers of exposure were assessed. Results Cigar smokers showed low levels of dependence. Cigar smoking alleviated withdrawal and craving symptoms, increased plasma nicotine concentration, and increased exhaled CO. Multiple regression analyses indicate that inhalation behaviors were associated with increased dependence and greater reductions in withdrawal symptoms upon cigar smoking. Large cigar smokers smoked longer and smoked more tobacco than small cigar and cigarillo smokers. Furthermore, large cigar smokers and self-reported inhalers were exposed to more nicotine than small cigar smokers and non-inhalers. Conclusions Our study suggests that cigar type and smoking behaviors affect dependence and nicotine exposure upon cigar smoking. These findings provide additional insight into the substantial risks associated with cigar smoking. PMID:29516029

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.

No difference in ad libitum energy intake in healthy men and women consuming beverages sweetened with fructose, glucose, or high-fructose corn syrup: a randomized trial.

PubMed

Kuzma, Jessica N; Cromer, Gail; Hagman, Derek K; Breymeyer, Kara L; Roth, Christian L; Foster-Schubert, Karen E; Holte, Sarah E; Callahan, Holly S; Weigle, David S; Kratz, Mario

2015-12-01

Increased energy intake is consistently observed in individuals consuming sugar-sweetened beverages (SSBs), likely mainly because of an inadequate satiety response to liquid calories. However, SSBs have a high content of fructose, the consumption of which acutely fails to trigger responses in key signals involved in energy homeostasis. It is unclear whether the fructose content of SSBs contributes to the increased energy intake in individuals drinking SSBs. We investigated whether the relative amounts of fructose and glucose in SSBs modifies ad libitum energy intake over 8 d in healthy adults without fructose malabsorption. We conducted 2 randomized, controlled, double-blind crossover studies to compare the effects of consuming 4 servings/d of a fructose-, glucose-, or aspartame-sweetened beverage (study A; n = 9) or a fructose-, glucose-, or high-fructose corn syrup (HFCS)-sweetened beverage (study B; n = 24) for 8 d on overall energy intake. SSBs were provided at 25% of estimated energy requirement, or an equivalent volume of the aspartame-sweetened beverage, and consumption was mandatory. All solid foods were provided at 125% of estimated energy requirements and were consumed ad libitum. In study A, ad libitum energy intake was 120% ± 10%, 117% ± 12%, and 102% ± 15% of estimated energy requirements when subjects consumed the fructose-, glucose-, and aspartame-sweetened beverages. Energy intake was significantly higher in the fructose and glucose phases than in the aspartame phase (P < 0.003 for each), with no difference between the fructose and glucose phases (P = 0.462). In study B, total energy intake during the fructose, HFCS, and glucose phases was 116% ± 14%, 116% ± 16%, and 116% ± 16% of the subject's estimated total energy requirements (P = 0.880). In healthy adults, total 8-d ad libitum energy intake was increased in individuals consuming SSBs compared with aspartame-sweetened beverages. The energy overconsumption observed in individuals consuming

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.

No difference in ad libitum energy intake in healthy men and women consuming beverages sweetened with fructose, glucose, or high-fructose corn syrup: a randomized trial1

PubMed Central

Kuzma, Jessica N; Cromer, Gail; Hagman, Derek K; Breymeyer, Kara L; Roth, Christian L; Foster-Schubert, Karen E; Holte, Sarah E; Callahan, Holly S; Weigle, David S; Kratz, Mario

2015-01-01

Background: Increased energy intake is consistently observed in individuals consuming sugar-sweetened beverages (SSBs), likely mainly because of an inadequate satiety response to liquid calories. However, SSBs have a high content of fructose, the consumption of which acutely fails to trigger responses in key signals involved in energy homeostasis. It is unclear whether the fructose content of SSBs contributes to the increased energy intake in individuals drinking SSBs. Objective: We investigated whether the relative amounts of fructose and glucose in SSBs modifies ad libitum energy intake over 8 d in healthy adults without fructose malabsorption. Design: We conducted 2 randomized, controlled, double-blind crossover studies to compare the effects of consuming 4 servings/d of a fructose-, glucose-, or aspartame-sweetened beverage (study A; n = 9) or a fructose-, glucose-, or high-fructose corn syrup (HFCS)–sweetened beverage (study B; n = 24) for 8 d on overall energy intake. SSBs were provided at 25% of estimated energy requirement, or an equivalent volume of the aspartame-sweetened beverage, and consumption was mandatory. All solid foods were provided at 125% of estimated energy requirements and were consumed ad libitum. Results: In study A, ad libitum energy intake was 120% ± 10%, 117% ± 12%, and 102% ± 15% of estimated energy requirements when subjects consumed the fructose-, glucose-, and aspartame-sweetened beverages. Energy intake was significantly higher in the fructose and glucose phases than in the aspartame phase (P < 0.003 for each), with no difference between the fructose and glucose phases (P = 0.462). In study B, total energy intake during the fructose, HFCS, and glucose phases was 116% ± 14%, 116% ± 16%, and 116% ± 16% of the subject’s estimated total energy requirements (P = 0.880). Conclusions: In healthy adults, total 8-d ad libitum energy intake was increased in individuals consuming SSBs compared with aspartame-sweetened beverages. The

Effects of modified foodservice practices in military dining facilities on ad libitum nutritional intake of US army soldiers.

PubMed

Crombie, Aaron P; Funderburk, LesLee K; Smith, Tracey J; McGraw, Susan M; Walker, Leila A; Champagne, Catherine M; Allen, H Raymond; Margolis, Lee M; McClung, Holly L; Young, Andrew J

2013-07-01

Modifying foodservice practices in military dining facilities could influence ad libitum nutritional intake patterns of soldiers. We aimed to determine how changes in foodservice operations consistent with 2005 Dietary Guidelines for Americans affected soldiers' ad libitum nutritional intake in military dining facilities (DFACs). Ten DFACs participated, and the intervention was implemented in five DFACs in an independently sampled, partial crossover design. Nutrient intake of diners was assessed during a test meal using digital photography, and customer satisfaction with foodservice was assessed via surveys at baseline (n=602), and again at 6 months (n=519) and 12 months (n=458) after the intervention was implemented. Volunteers were US Army active duty soldiers recruited from among diners at 10 DFACs on Fort Bragg, NC. Primary outcomes were intakes of energy and total fat, and percent energy from fat and saturated fat. Differences between diners' intakes in control and intervention DFACs were assessed using independent samples t tests. At 6 months after implementing the intervention, diners at intervention DFACs had significantly lower lunchtime intakes of energy (945±338 kcal vs 1,061±380 kcal), total fat (38±19 g vs 47±25 g), percent energy from fat (35%±10% vs 39%±11%) and saturated fat (4.7%±1.7% vs 5.6%±2.3%), discretionary fat (30±18 g vs 39±24 g), and refined grains (2.3±1.7 oz equivalents vs 2.8±2.4 oz equivalents) compared with diners at control DFACs. Further, diners at intervention DFACs rated customer satisfaction higher than diners at control DFACs. These findings suggest that modest changes in military DFAC serving practices to promote healthy eating and food selection can facilitate positive changes in soldiers' nutritional intake. Published by Elsevier Inc.

Effects of 7 days on an ad libitum low-fat vegan diet: the McDougall Program cohort.

PubMed

McDougall, John; Thomas, Laurie E; McDougall, Craig; Moloney, Gavin; Saul, Bradley; Finnell, John S; Richardson, Kelly; Petersen, Katelin Mae

2014-10-14

Epidemiologic evidence, reinforced by clinical and laboratory studies, shows that the rich Western diet is the major underlying cause of death and disability (e.g, from cardiovascular disease and type 2 diabetes) in Western industrialized societies. The objective of this study is to document the effects that eating a low-fat (≤10% of calories), high-carbohydrate (~80% of calories), moderate-sodium, purely plant-based diet ad libitum for 7 days can have on the biomarkers of cardiovascular disease and type 2 diabetes. Retrospective analysis of measurements of weight, blood pressure, blood sugar, and blood lipids and estimation of cardiovascular disease risk at baseline and day 7 from 1615 participants in a 10-day residential dietary intervention program from 2002 to 2011. Wilcoxon's signed-rank test was used for testing the significance of changes from baseline. The median (interquartile range, IQR) weight loss was 1.4 (1.8) kg (p < .001). The median (IQR) decrease in total cholesterol was 22 (29) mg/dL (p < .001). Even though most antihypertensive and antihyperglycemic medications were reduced or discontinued at baseline, systolic blood pressure decreased by a median (IQR) of 8 (18) mm Hg (p < .001), diastolic blood pressure by a median (IQR) of 4 (10) mm Hg (p < .001), and blood glucose by a median (IQR) of 3 (11) mg/dL (p < .001). For patients whose risk of a cardiovascular event within 10 years was >7.5% at baseline, the risk dropped to 5.5% (>27%) at day 7 (p < .001). A low-fat, starch-based, vegan diet eaten ad libitum for 7 days results in significant favorable changes in commonly tested biomarkers that are used to predict future risks for cardiovascular disease and metabolic diseases.

Soda Consumption During Ad Libitum Food Intake Predicts Weight Change

PubMed Central

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

2013-01-01

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 [BMI] 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%) 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. PMID:24321742

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.

Phenotypic relationships among methane production traits assessed under ad libitum feeding of beef cattle.

PubMed

Bird-Gardiner, T; Arthur, P F; Barchia, I M; Donoghue, K A; Herd, R M

2017-10-01

Angus cattle from 2 beef cattle projects in which daily methane production (MPR) was measured were used in this study to examine the nature of the relationships among BW, DMI, and methane traits of beef cattle fed ad libitum on a roughage diet or a grain-based feedlot diet. In both projects methane was measured using the GreenFeed Emission Monitoring system, which provides multiple short-term breath measures of methane production. The data used for this study were from 119 Angus heifers over 15 d on a roughage diet and 326 Angus steers over 70 d on a feedlot diet. Mean (±SD) age, BW, and DMI were 372 ± 28 d, 355 ± 37 kg, and 8.1 ± 1.3 kg/d for the heifers and 554 ± 86 d, 577 ± 69 kg, and 13.3 ± 2.0 kg/d for the steers, respectively. The corresponding mean MPR was 212 g/d for heifers and 203 g/d for steers. Additional traits studied included methane yield (MY; MPR/DMI), methane intensity (MPR/BW), and 3 forms of residual methane production (RMP), which is a measure of actual minus predicted MPR. For RMP, RMP, and RMP predicted MPR were obtained by regression of MPR on BW, on DMI, and on both DMI and BW, respectively. The 2 data sets were analyzed separately using the same statistical procedures. For both feed types the relationships between MPR and DMI and between MPR and BW were both positive and linear. The correlation between MPR and DMI was similar to that between MPR and BW, although the correlations were stronger for the roughage diet ( = 0.75 for MPR vs. DMI; = 0.74 for MPR vs. BW) than the grain-based diet ( = 0.62 for MPR vs. DMI; = 0.66 for MPR vs. BW). The correlation between MY and DMI was negative and moderate for the roughage ( = -0.68) and grain-based ( = -0.59) diets, a finding that is different from the nonsignificant correlations reported in studies of cattle on a restricted roughage diet. The 3 RMP traits were strongly correlated ( values from 0.76 to 0.99) with each other for both the roughage and the grain-based diets, which indicates

Growth performance, rumen fermentation, nutrient utilization, and metabolic profile of dairy heifers limit-fed distillers dried grains with ad libitum forage.

PubMed

Manthey, A K; Anderson, J L

2018-01-01

The objective of this study was to determine the effects of feeding a corn- and soybean-product-based concentrate mix or distillers dried grains with solubles concentrate mix with ad libitum grass hay to dairy heifers. A 16-wk randomized complete block design study was conducted using 24 heifers [18 Holstein and 6 Brown Swiss; 219 ± 2 d of age (±standard deviation); 230 ± 4 kg of body weight] to evaluate the effect of diet on dry matter intake (DMI), growth performance, rumen fermentation, metabolic profile, and nutrient digestibility. Treatments were (1) corn and soybean product concentrate mix, and (2) distillers-dried-grains-with-solubles-based concentrate mix (DDG). Both concentrate mixes were limit-fed at 0.8% of body weight and grass hay was offered ad libitum. Heifers were individually fed using Calan gates and orts were recorded daily at feeding. Heifers were weighed every 2 wk and ration concentrate mix offered was adjusted accordingly. Frame measurements and body condition score were recorded every 2 wk. Rumen fluid was collected via esophageal tubing during wk 12 and 16 for pH, ammonia N, and volatile fatty acid analysis. Jugular blood samples were collected every 4 wk for metabolite and metabolic hormone analysis. Total-tract digestibility of nutrients was evaluated during wk 16 by fecal grab sampling. No treatment by week interactions were observed for any of the growth measurements and growth measurements and DMI did not differ between treatments. A treatment by time interaction was observed for rumen butyrate percentage with heifers fed DDG having a greater percentage. Total volatile fatty acid concentration, acetate molar percentage, and acetate:propionate decreased with the DDG treatment, whereas propionate molar percentage increased. No treatment by week interactions were observed for any of the metabolites or metabolic hormones measured. A tendency was observed for glucose and plasma urea nitrogen concentration to decrease with DDG. Plasma

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

Direct and correlated responses to selection in two lines of rabbits selected for feed efficiency under ad libitum and restricted feeding: III. Digestion and excretion of nitrogen and minerals.

PubMed

Gidenne, T; Fortun-Lamothe, L; Bannelier, C; Molette, C; Gilbert, H; Chemit, M L; Segura, M; Benitez, F; Richard, F; Garreau, H; Drouilhet, L

2017-03-01

Two rabbit lines have been created to result in better feed efficiency: the ConsoResidual line was selected for a lower residual feed intake under ad libitum feeding, and the ADGrestrict line was selected for higher ADG under restricted feeding (-20% of ad libitum). The present study aimed to analyze the digestion and excretion of N and minerals from 29 to 63 d of age of these 2 lines compared with an unselected control line (G0) under 2 feeding levels (ad libitum or restricted). The ADGrestrict line had greater digestibility compared with G0 (+1.3% for OM and N; < 0.05), and the ConsoResidual line had intermediate values. There was no genetic line effect on the digestibility of N and P and on minerals concentrations (P, Zn, and Cu) in the feces and in the urine. The N balance was improved for the 2 selected lines (+5%; < 0.05), leading to a reduced N output through the feces (0.06 g/d compared with G0; < 0.001) and the urine (-0.07 g/d; < 0.05) and to an improved N retention ratio (+3% compared with G0). Over the whole fattening period (d 29-63), significant differences were observed among lines only when fed ad libitum, with 13% greater DM fecal output and 5% greater N fecal output for G0. The N excretion in urine was 2 g less in the 2 selected lines, leading to a reduction of total N release of 4.4 g (compared with G0). The P excretion in feces (12 g) or urine (0.1 g) did not differ among the 3 lines. Over the whole fattening period and for ad libitum-fed rabbits, the 5% improvement in feed efficiency ( < 0.01) for the 2 selected lines corresponded to 400 g less feed intake (-8%) and to 20 g less N intake. The fecal excretion of the ADGrestrict and ConsoResidual lines were reduced by 200 g DM ( < 0.01), corresponding to 417 g fresh matter and 5 g of N. The excretion in minerals (P, Zn, and Cu) was not affected by the line. The feeding level strongly reduced the fecal and urine outputs (-50 and -60%, respectively; < 0.001). Higher digestibility coefficients ( < 0

Thirst responses following high intensity intermittent exercise when access to ad libitum water intake was permitted, not permitted or delayed.

PubMed

Mears, Stephen A; Watson, Phillip; Shirreffs, Susan M

2016-04-01

An increase in subjective feelings of thirst and ad libitum drinking caused by an increase in serum osmolality have been observed following high intensity intermittent exercise (HIIE) compared to continuous exercise. The increase in serum osmolality is closely linked to the rise in blood lactate and serum sodium concentrations. However, during an ensuing recovery period after HIIE when serum osmolality will decrease, the resultant effect on sensations of thirst and subsequent water intake is unclear. Therefore the aim of the study was to assess the sensations of thirst and subsequent effect on ad libitum water consumption when water intake was immediately allowed, delayed or prevented following a period of HIIE. Twelve males (26±4 years, 80.1±9.3 kg, 1.81±0.05 m, V̇O2peak 60.1±8.9 ml·kg(-1)·min(-1)) participated in three randomised trials undertaken 7-14 days apart. Participants rested for 30 min then completed a 60 min HIIE exercise period (20×1 min at 100% V̇O2peak with 2 min rest) followed by 60 min of recovery, during which ad libitum water intake was provided immediately (W), delayed until the final 30 min (W30) or not permitted (NW). Body mass was measured at the start and end of the trial. Blood lactate and serum sodium concentrations serum osmolality and sensation of thirst were measured at baseline, immediately post-exercise and during the recovery. Body mass loss was different between all trials (W: 0.25±0.45, W30: 0.49±0.37, NW: 1.29±0.37%; p<0.05). Sensations of thirst peaked post-exercise and decreased in W and W30 following water ingestion (p<0.05). Total voluntary water intake was greater in W trial (0.846±0.417 vs. 0.630±0.277l; p<0.05) but was similar during the first 30 min period of allowed drinking (0.618±0.297 vs. 0.630±0.277l; p>0.05). Serum osmolality (299±6 vs. 298±5 vs. 298±3 mOsmol·kg(-1)), blood lactate (7.1±1.1 vs. 7.2±1.1 vs. 7.1±1.2 mmol·l(-1)) and serum sodium concentrations (142±2 vs. 145±2 vs. 145±2 mmol

Ad libitum fluid consumption via self- or external administration.

PubMed

Yeargin, Susan W; Finn, Megan E; Eberman, Lindsey E; Gage, Matthew J; McDermott, Brendon P; Niemann, Andrew

2015-01-01

During team athletic events, athletic trainers commonly provide fluids with water bottles. When a limited number of water bottles exist, various techniques are used to deliver fluids. To determine whether fluid delivered via water-bottle administration influenced fluid consumption and hydration status. Crossover study. Outdoor field (22.2°C ± 3.5°C). Nineteen participants (14 men, 5 women, age = 30 ± 10 years, height = 176 ± 8 cm, mass = 72.5 ± 10 kg) were recruited from the university and local running clubs. The independent variable was fluid delivery with 3 levels: self-administration with mouth-to-bottle direct contact (SA-DC), self-administration with no contact between mouth and bottle (SA-NC), and external administration with no contact between the mouth and the bottle (EA-NC). Participants warmed up for 10 minutes before completing 5 exercise stations, after which an ad libitum fluid break was given, for a total of 6 breaks. We measured the fluid variables of total volume consumed, total number of squirts, and average volume per squirt. Hydration status via urine osmolality and body-mass loss, and perceptual variables for thirst and fullness were recorded. We calculated repeated-measures analyses of variance to assess hydration status, fluid variables, and perceptual measures to analyze conditions across time. The total volume consumed for EA-NC was lower than for SA-DC (P = .001) and SA-NC (P = .001). The total number of squirts for SA-DC was lower than for SA-NC (P = .009). The average volume per squirt for EA-NC was lower than for SA-DC (P = .020) and SA-NC (P = .009). Participants arrived (601.0 ± 21.3 mOsm/L) and remained (622.3 ± 38.3 mOsm/L) hydrated, with no difference between conditions (P = .544); however, the EA-NC condition lost more body mass than did the SA-DC condition (P = .001). There was no main effect for condition on thirst (P = .147) or fullness (P = .475). External administration of fluid decreased total volume consumed via a

Ad libitum fluid intake does not prevent dehydration in suboptimally hydrated young soccer players during a training session of a summer camp.

PubMed

Arnaoutis, Giannis; Kavouras, Stavros A; Kotsis, Yiannis P; Tsekouras, Yiannis E; Makrillos, Michalis; Bardis, Costas N

2013-06-01

There is a lack of studies concerning hydration status of young athletes exercising in the heat. To assess preexercise hydration status in young soccer players during a summer sports camp and to evaluate body- water balance after soccer training sessions. Initial hydration status was assessed in 107 young male soccer players (age 11-16 yr) during the 2nd day of the camp. Seventy-two athletes agreed to be monitored during 2 more training sessions (3rd and 5th days of the camp) to calculate dehydration via changes in body weight, while water drinking was allowed ad libitum. Hydration status was assessed via urine specific gravity (USG), urine color, and changes in total body weight. Mean environmental temperature and humidity were 27.2 ± 2 °C and 57% ± 9%, respectively. According to USG values, 95 of 107 of the players were hypohydrated (USG ≥ 1.020) before practice. The prevalence of dehydration observed was maintained on both days, with 95.8% and 97.2% of the players being dehydrated after the training sessions on the 3rd and 5th days, respectively. Despite fluid availability, 54 of the 66 (81.8%) dehydrated players reduced their body weight (-0.35 ± 0.04 kg) as a response to training, while 74.6% (47 out of the 63) further reduced their body weight (-0.22 ± 0.03 kg) after training on the 5th day. Approximately 90% of the young soccer players who began exercising under warm weather conditions were hypohydrated, while drinking ad libitum during practice did not prevent further dehydration in already dehydrated players.

Effect of 24-h severe energy restriction on appetite regulation and ad libitum energy intake in lean men and women.

PubMed

Clayton, David J; Burrell, Kirsty; Mynott, Georgina; Creese, Mark; Skidmore, Nicola; Stensel, David J; James, Lewis J

2016-12-01

Intermittent severe energy restriction (SER) can induce substantial weight loss, but the appetite regulatory responses to SER are unknown and may dictate long-term dietary adherence. We determined the effect of 24-h SER on appetite regulation, metabolism, and energy intake. Eighteen lean men and women completed two 3-d trials in randomized, counterbalanced order. On day 1 subjects consumed standardized diets containing 100% (mean ± SD: 9.3 ± 1.3 MJ; energy balance) or 25% [2.3 ± 0.3 MJ; energy restriction (ER)] of energy requirements. On day 2, a standardized breakfast was consumed, with plasma concentrations of acylated ghrelin, glucagon-like peptide 1, insulin, glucose, and nonesterified fatty acids determined for 4 h. Ad libitum energy intake was assessed at lunch and dinner with subjective appetite and resting metabolism assessed throughout. On day 3, ad libitum energy intake was assessed at breakfast and by weighed food records. Energy intake was 7% greater on day 2 (P < 0.05) during ER but not significantly different on day 3 (P = 0.557). Subjective appetite was greater during ER on the morning of day 2 (P < 0.05) but was not significantly different thereafter (P > 0.145). During ER, postprandial concentrations of acylated ghrelin were lower (P < 0.05), whereas glucose (P < 0.05) and nonesterified fatty acids (P < 0.0001) were higher. Postprandial glucagon-like peptide 1 7-36 (P = 0.784) and insulin (P = 0.06) concentrations were not significantly different between trials. Energy expenditure was lower during ER in the morning (P < 0.01). In lean young adults, 24-h SER transiently elevated subjective appetite and marginally increased energy intake, but hormonal appetite markers did not respond in a manner indicative of hyperphagia. These results suggest that intermittent SER might be useful to attenuate energy intake and control body weight in this population. This trial was registered at www.clinicaltrials.gov.uk as NCT02696772. © 2016 American Society

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

NASA Astrophysics Data System (ADS)

Čubrović, Mihailo; Zaanen, Jan; Schalm, Koenraad

2011-10-01

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

Segmented strings in AdS 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 studymore » several examples of closed segmented strings in AdS 3 and find an unexpected quasi-periodic behavior. Here, 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.« less

Segmented strings in AdS 3

DOE PAGES

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

2015-11-17

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 studymore » several examples of closed segmented strings in AdS 3 and find an unexpected quasi-periodic behavior. Here, 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.« less

The effect of sugar-sweetened beverage intake on energy intake in an ad libitum 6-month low-fat high-carbohydrate diet.

PubMed

Munsters, Marjet J M; Saris, Wim H M

2010-01-01

The increased incidence of obesity coincides with an increased consumption of sugar-sweetened beverages (SSBs). This study investigated the effect of SSB intake on energy intake in an ad libitum 6-month low-fat high-carbohydrate diet in a reanalysis of the CARMEN data. Forty-seven overweight-to-obese men and women participated in the Maastricht centre of the randomized controlled CARMEN study. They were allocated to a control (habitual) diet group (CD), a low-fat (-10 energy percent, En%) high simple carbohydrate (SCHO) or low-fat high complex carbohydrate group (CCHO) (SCHO vs. CCHO: 1.5 vs. 0.5) using a controlled laboratory shop system. Reanalyses were made for the energy, amount and density of all drinks and in particular of sweetened beverages (SBs). The SCHO and CD group could select non-diet SBs, including soft drinks and fruit juices, while the CCHO group received SB alternatives. Energy intake decreased in the CCHO and SCHO groups versus the CD group (-2.7 ± 0.4 MJ/day CCHO group vs. -0.2 ± 0.5 MJ/day CD group, p < 0.01; -1.4 ± 0.4 MJ/day SCHO group, not significant). Simple carbohydrate intake increased significantly in the SCHO group versus the CCHO and CD groups (+10.8 ± 1.6 vs. -2.0 ± 0.9 and -0.5 ± 1.1 En%; p < 0.001). In the SCHO and CD groups, energy intake from SBs increased significantly (+187 ± 114 and +101 ± 83 kJ/day, respectively; -432 ± 72 kJ/day in the CCHO group; p < 0.001). Simple carbohydrate intake increased through enhanced intake of non-diet SBs in the SCHO group. Fat reduction combined with only diet SBs in an ad libitum situation has a greater impact on energy intake than fat reduction combined with non-diet SBs. Copyright © 2010 S. Karger AG, Basel.

Warped AdS3 black holes

NASA Astrophysics Data System (ADS)

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

2009-03-01

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

Warped AdS3 black holes

NASA Astrophysics Data System (ADS)

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

2009-03-01

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

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. Copyright © 2015 Elsevier Inc. All rights reserved.

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Ad libitum Low-Carbohydrate High-Fat Dieting in Middle-Age Male Runners.

PubMed

Heatherly, Alexander J; Killen, Lauren G; Smith, Ashton F; Waldman, Hunter S; Seltmann, Christie L; Hollingsworth, Angela; O'Neal, Eric K

2018-03-01

This study examined the effects of a 3-wk ad libitum, low-carbohydrate (<50 g·d) high-fat (~70% of calories) (LCHF) diet on markers of endurance performance in middle-age, recreationally competitive male runners. All subjects (n = 8) after their normal high-carbohydrate (HC) diet had anthropometric measures assessed and completed five 10-min running bouts at multiple individual race paces in the heat while physiological variables, metabolic variables, and perceptual responses were recorded. After 20 min of rest, participants completed a 5-km time trial on a road course. Subjects then consumed an LCHF diet for 3 wk and returned for repeat testing. Body mass and seven-site skinfold thickness sum decreased by approximately 2.5 kg (P < 0.01) and 13 mm (P < 0.05) after LCHF diet. Rectal temperature was higher after the first 10 min of exercise (37.7°C ± 0.3°C vs 37.3°C ± 0.2°C) in the HC diet but did not differ at any other time with LCHF diet. Heart rate and perceptual measures did not display any consistent differences between treatments excluding thirst sensation for LCHF diet. RER and carbohydrate oxidation declined significantly, whereas fat oxidation increased after LCHF diet for every pace (P < 0.01). There was no significant difference (P = 0.25) in a 5-km time trial performance, but LCHF diet (23.45 ± 2.25 min) displayed a trend of improved performance versus HC (23.92 ± 2.57 min). Improved body composition and fat oxidation from LCHF diet potentially negate expected performance decrement from reduced carbohydrate use late in exercise for nonelite runners. An acute decrease in training capacity is expected; however, if performance improvement is not exhibited after 3 wk, diet cessation is suggested for negative responders.

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Tensionless string spectra on AdS3

NASA Astrophysics Data System (ADS)

Gaberdiel, Matthias R.; Gopakumar, Rajesh

2018-05-01

The spectrum of superstrings on AdS3 × S3 × M 4 with pure NS-NS flux is analysed for the background where the radius of the AdS space takes the minimal value ( k = 1). Both for M 4 = S3 × S1 and M 4 = T 4 we show that there is a special set of physical states, coming from the bottom of the spectrally flowed continuous representations, which agree in precise detail with the single particle spectrum of a free symmetric product orbifold. For the case of AdS3 × S3 × T 4 this relies on making sense of the world-sheet theory at k = 1, for which we make a concrete proposal. We also comment on the implications of this striking result.

AdS7/CFT6 with orientifolds

NASA Astrophysics Data System (ADS)

Apruzzi, Fabio; Fazzi, Marco

2018-01-01

AdS7 solutions of massive type IIA have been classified, and are dual to a large class of six-dimensional (1, 0) SCFT's whose tensor branch deformations are described by linear quivers of SU groups. Quivers and AdS vacua depend solely on the group theory data of the NS5-D6-D8 brane configurations engineering the field theories. This has allowed for a direct holographic match of their a conformal anomaly. In this paper we extend the match to cases where O6 and O8-planes are present, thereby introducing SO and USp groups in the quivers. In all of them we show that the a anomaly computed in supergravity agrees with the holographic limit of the exact field theory result, which we extract from the anomaly polynomial. As a byproduct we construct special AdS7 vacua dual to nonperturbative F-theory configurations. Finally, we propose a holographic a-theorem for six-dimensional Higgs branch RG flows.

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.

Two Virasoro symmetries in stringy warped AdS 3

DOE PAGES

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

2014-12-02

We study three-dimensional consistent truncations of type IIB supergravity which admit warped AdS 3 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 AdS 3. Consequently, for each consistent choice of boundary conditions in AdS 3, we can define a consistent phase space in warped AdS 3 with identical conserved charges. This way, we easily obtain a Virasoro × Virasoro asymptotic symmetry algebra in warped AdS 3; two different types of Virasoro × Kač-Moody symmetriesmore » are also consistent alternatives. Next, we study the phase space of these theories when propagating modes are included. We show that, as long as one can define a conserved symplectic form without introducing instabilities, the Virasoro × Virasoro asymptotic symmetries can be extended to the entire (linearised) phase space. In conclusion, this implies that, at least at semi-classical level, consistent theories of gravity in warped AdS 3 are described by a two-dimensional conformal field theory, as long as stability is not an issue.« less

Two Virasoro symmetries in stringy warped AdS 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

We study three-dimensional consistent truncations of type IIB supergravity which admit warped AdS 3 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 AdS 3. Consequently, for each consistent choice of boundary conditions in AdS 3, we can define a consistent phase space in warped AdS 3 with identical conserved charges. This way, we easily obtain a Virasoro × Virasoro asymptotic symmetry algebra in warped AdS 3; two different types of Virasoro × Kač-Moody symmetriesmore » are also consistent alternatives. Next, we study the phase space of these theories when propagating modes are included. We show that, as long as one can define a conserved symplectic form without introducing instabilities, the Virasoro × Virasoro asymptotic symmetries can be extended to the entire (linearised) phase space. In conclusion, this implies that, at least at semi-classical level, consistent theories of gravity in warped AdS 3 are described by a two-dimensional conformal field theory, as long as stability is not an issue.« less

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.

Minimum length of the adaptation and collection period in digestibility trials with sheep fed ad libitum only forage or forage plus concentrate.

PubMed

Farenzena, R; Kozloski, G V; Gindri, M; Stefanello, S

2017-10-01

Two in vivo digestibility trials with sheep were conducted to identify the minimum period length of feeding a new diet to obtain reproducible values of nutritional variables onward and the minimum length of collection period as to obtain maximal precision for each variable. Trial 1 was conducted with ten Polwarth male sheep (34 ± 5 kg body weight (BW)) throughout three 21-day periods, in a completely randomized two-way crossover design. The animals were divided into two groups (Group A and B, n = 5 per group) which were fed ad libitum with a sequence of the following diets throughout the periods: Group A: hay - hay plus concentrate - hay; Group B: hay plus concentrate - hay - hay plus concentrate. The concentrate was included in a proportion of 0.33 of the total diet. The intake, and the faecal and urinary excretion were measured daily throughout the experiment. For evaluating rumen fermentation variables, in Trial 2 four Santa Inês male sheep (65 ± 5 kg BW) fitted with ruminal cannula were used. The animals were randomly divided into two groups (n = 2 per group), and the trial was conducted through four 21 days experimental period, in a three-way crossover design, using experimental diets and feeding management similar to Trial 1. The results indicated that, even though no clear or consistent steady-state condition was identified for rumen fermentation or urinary excretion variables, the adaptation period for measuring OM digestibility in in vivo trials with sheep fed ad libitum where the diet shifts from one of only hay to another containing concentrate, or vice-versa, should be at least 12 days long. Moreover, although no precision improvement was obtained by increasing the collection period above 1 day for measuring OM digestibility, the minimal length of collection period should be 4 days for measuring faecal excretion variables and 7 days for measuring urinary excretion variables. Journal of Animal Physiology and Animal Nutrition © 2016

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.

Floquet scalar dynamics in global AdS

NASA Astrophysics Data System (ADS)

Biasi, Anxo; Carracedo, Pablo; Mas, Javier; Musso, Daniele; Serantes, Alexandre

2018-04-01

We study periodically driven scalar fields and the resulting geometries with global AdS asymptotics. These solutions describe the strongly coupled dynamics of dual finite-size quantum systems under a periodic driving which we interpret as Floquet condensates. They span a continuous two-parameter space that extends the linearized solutions on AdS. We map the regions of stability in the solution space. In a significant portion of the unstable subspace, two very different endpoints are reached depending upon the sign of the perturbation. Collapse into a black hole occurs for one sign. For the opposite sign instead one attains a regular solution with periodic modulation. We also construct quenches where the driving frequency and amplitude are continuously varied. Quasistatic quenches can interpolate between pure AdS and sourced solutions with time periodic vev. By suitably choosing the quasistatic path one can obtain boson stars dual to Floquet condensates at zero driving field. We characterize the adiabaticity of the quenching processes. Besides, we speculate on the possible connections of this framework with time crystals.

Antismoking Ads at the Point of Sale: The Influence of Ad Type and Context on Ad Reactions.

PubMed

Kim, Annice; Nonnemaker, James; Guillory, Jamie; Shafer, Paul; Parvanta, Sarah; Holloway, John; Farrelly, Matthew

2017-06-01

Efforts are underway to educate consumers about the dangers of smoking at the point of sale (POS). Research is limited about the efficacy of POS antismoking ads to guide campaign development. This study experimentally tests whether the type of antismoking ad and the context in which ads are viewed influence people's reactions to the ads. A national convenience sample of 7,812 adult current smokers and recent quitters was randomized to 1 of 39 conditions. Participants viewed one of the four types of antismoking ads (negative health consequences-graphic, negative social consequences-intended emotive, benefits of quitting-informational, benefits of quitting-graphic) in one of the three contexts (alone, next to a cigarette ad, POS tobacco display). We assessed participants' reactions to the ads, including perceived effectiveness, negative emotion, affective dissonance, and motivational reaction. Graphic ads elicited more negative emotion and affective dissonance than benefits of quitting ads. Graphic ads elicited higher perceived effectiveness and more affective dissonance than intended emotive ads. Antismoking ads fared best when viewed alone, and graphic ads were least influenced by the context in which they were viewed. These results suggest that in developing POS campaigns, it is important to consider the competitive pro-tobacco context in which antismoking ads will be viewed.

Loops in AdS from conformal field theory

DOE PAGES

Aharony, Ofer; Alday, Luis F.; Bissi, Agnese; ...

2017-07-10

We propose and demonstrate a new use for conformal field theory (CFT) crossing equations in the context of AdS/CFT: the computation of loop amplitudes in AdS, dual to non-planar correlators in holographic CFTs. Loops in AdS are largely unexplored, mostly due to technical difficulties in direct calculations. We revisit this problem, and the dual 1=N expansion of CFTs, in two independent ways. The first is to show how to explicitly solve the crossing equations to the first subleading order in 1=N 2, given a leading order solution. This is done as a systematic expansion in inverse powers of the spin, to all orders. These expansions can be resummed, leading to the CFT data for nite values of the spin. Our second approach involves Mellin space. We show how the polar part of the four-point, loop-level Mellin amplitudes can be fully reconstructed from the leading-order data. The anomalous dimensions computed with both methods agree. In the case ofmore » $$\\phi$$ 4 theory in AdS, our crossing solution reproduces a previous computation of the one-loop bubble diagram. We can go further, deriving the four-point scalar triangle diagram in AdS, which had never been computed. In the process, we show how to analytically derive anomalous dimensions from Mellin amplitudes with an in nite series of poles, and discuss applications to more complicated cases such as the N = 4 super-Yang-Mills theory.« less

Loops in AdS from conformal field theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aharony, Ofer; Alday, Luis F.; Bissi, Agnese

We propose and demonstrate a new use for conformal field theory (CFT) crossing equations in the context of AdS/CFT: the computation of loop amplitudes in AdS, dual to non-planar correlators in holographic CFTs. Loops in AdS are largely unexplored, mostly due to technical difficulties in direct calculations. We revisit this problem, and the dual 1=N expansion of CFTs, in two independent ways. The first is to show how to explicitly solve the crossing equations to the first subleading order in 1=N 2, given a leading order solution. This is done as a systematic expansion in inverse powers of the spin, to all orders. These expansions can be resummed, leading to the CFT data for nite values of the spin. Our second approach involves Mellin space. We show how the polar part of the four-point, loop-level Mellin amplitudes can be fully reconstructed from the leading-order data. The anomalous dimensions computed with both methods agree. In the case ofmore » $$\\phi$$ 4 theory in AdS, our crossing solution reproduces a previous computation of the one-loop bubble diagram. We can go further, deriving the four-point scalar triangle diagram in AdS, which had never been computed. In the process, we show how to analytically derive anomalous dimensions from Mellin amplitudes with an in nite series of poles, and discuss applications to more complicated cases such as the N = 4 super-Yang-Mills theory.« less

Loops in AdS from conformal field theory

NASA Astrophysics Data System (ADS)

Aharony, Ofer; Alday, Luis F.; Bissi, Agnese; Perlmutter, Eric

2017-07-01

We propose and demonstrate a new use for conformal field theory (CFT) crossing equations in the context of AdS/CFT: the computation of loop amplitudes in AdS, dual to non-planar correlators in holographic CFTs. Loops in AdS are largely unexplored, mostly due to technical difficulties in direct calculations. We revisit this problem, and the dual 1 /N expansion of CFTs, in two independent ways. The first is to show how to explicitly solve the crossing equations to the first subleading order in 1 /N 2, given a leading order solution. This is done as a systematic expansion in inverse powers of the spin, to all orders. These expansions can be resummed, leading to the CFT data for finite values of the spin. Our second approach involves Mellin space. We show how the polar part of the four-point, loop-level Mellin amplitudes can be fully reconstructed from the leading-order data. The anomalous dimensions computed with both methods agree. In the case of ϕ 4 theory in AdS, our crossing solution reproduces a previous computation of the one-loop bubble diagram. We can go further, deriving the four-point scalar triangle diagram in AdS, which had never been computed. In the process, we show how to analytically derive anomalous dimensions from Mellin amplitudes with an infinite series of poles, and discuss applications to more complicated cases such as the N = 4 super-Yang-Mills theory.

Worldsheet scattering in AdS3/CFT2

NASA Astrophysics Data System (ADS)

Sundin, Per; Wulff, Linus

2013-07-01

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

Spinning AdS loop diagrams: two point functions

NASA Astrophysics Data System (ADS)

Giombi, Simone; Sleight, Charlotte; Taronna, Massimo

2018-06-01

We develop a systematic approach to evaluating AdS loop amplitudes with spinning legs based on the spectral (or "split") representation of bulk-to-bulk propagators, which re-expresses loop diagrams in terms of spectral integrals and higher-point tree diagrams. In this work we focus on 2pt one-loop Witten diagrams involving totally symmetric fields of arbitrary mass and integer spin. As an application of this framework, we study the contribution to the anomalous dimension of higher-spin currents generated by bubble diagrams in higher-spin gauge theories on AdS.

Holography in Lovelock Chern-Simons AdS gravity

NASA Astrophysics Data System (ADS)

Cvetković, Branislav; Miskovic, Olivera; Simić, Dejan

2017-08-01

We analyze holographic field theory dual to Lovelock Chern-Simons anti-de Sitter (AdS) gravity in higher dimensions using first order formalism. We first find asymptotic symmetries in the AdS sector showing that they consist of local translations, local Lorentz rotations, dilatations and non-Abelian gauge transformations. Then, we compute 1-point functions of energy-momentum and spin currents in a dual conformal field theory and write Ward identities. We find that the holographic theory possesses Weyl anomaly and also breaks non-Abelian gauge symmetry at the quantum level.

Gauge boson exchange in AdS d+1

NASA Astrophysics Data System (ADS)

D'Hoker, Eric; Freedman, Daniel Z.

1999-04-01

We study the amplitude for exchange of massless gauge bosons between pairs of massive scalar fields in anti-de Sitter space. In the AdS/CFT correspondence this amplitude describes the contribution of conserved flavor symmetry currents to 4-point functions of scalar operators in the boundary conformal theory. A concise, covariant, Y2K compatible derivation of the gauge boson propagator in AdS d + 1 is given. Techniques are developed to calculate the two bulk integrals over AdS space leading to explicit expressions or convenient, simple integral representations for the amplitude. The amplitude contains leading power and sub-leading logarithmic singularities in the gauge boson channel and leading logarithms in the crossed channel. The new methods of this paper are expected to have other applications in the study of the Maldacena conjecture.

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.

Vacuum degeneracy and Conformal Mass in Lovelock AdS gravity

NASA Astrophysics Data System (ADS)

Arenas-Henriquez, Gabriel; Miskovic, Olivera; Olea, Rodrigo

2017-11-01

It is shown that the notion of Conformal Mass can be defined within a given anti-de Sitter (AdS) branch of a Lovelock gravity theory as long as the corresponding vacuum is not degenerate. Indeed, conserved charges obtained by the addition of Kounterterms to the bulk action turn out to be proportional to the electric part of the Weyl tensor, when the fall-off of a generic solution in that AdS branch is considered. The factor of proportionality is the degeneracy condition for the vacua in the particular Lovelock AdS theory under study. This last feature explains the obstruction to define Conformal Mass in the degenerate case.

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

PubMed Central

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

2016-01-01

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

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

PubMed

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

2016-01-01

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

Diffusion and chaos from near AdS 2 horizons

DOE PAGES

Blake, Mike; Donos, Aristomenis

2017-02-03

We calculate the thermal diffusivity D =more » $$\\kappa/c_\\rho$$ and butterfy velocity $$\\upsilon_\\beta$$ in holographic models that flow to $$AdS_2$$ x $R^d$ fixed points in the infra-red. We show that both these quantities are governed by the same irrelevant deformation of $$AdS_2$$ and hence establish a simple relationship between them. When this deformation corresponds to a universal dilaton mode of dimension $$\\Delta$$ = 2 then this relationship is always given by D = $$\\upsilon_B^2$$/(2$$\\pi$$T).« less

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.

Geometry and supersymmetry of heterotic warped flux AdS backgrounds

NASA Astrophysics Data System (ADS)

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

2015-07-01

We classify the geometries of the most general warped, flux AdS backgrounds of heterotic supergravity up to two loop order in sigma model perturbation theory. We show under some mild assumptions that there are no AdS n backgrounds with n ≠ 3. Moreover the warp factor of AdS3 backgrounds is constant, the geometry is a product AdS 3 × M 7 and such solutions preserve, 2, 4, 6 and 8 supersymmetries. The geometry of M 7 has been specified in all cases. For 2 supersymmetries, it has been found that M 7 admits a suitably restricted G 2 structure. For 4 supersymmetries, M 7 has an SU(3) structure and can be described locally as a circle fibration over a 6-dimensional KT manifold. For 6 and 8 supersymmetries, M 7 has an SU(2) structure and can be described locally as a S 3 fibration over a 4-dimensional manifold which either has an anti-self dual Weyl tensor or a hyper-Kähler structure, respectively. We also demonstrate a new Lichnerowicz type theorem in the presence of α' corrections.

[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,…

Thermodynamic and classical instability of AdS black holes in fourth-order gravity

NASA Astrophysics Data System (ADS)

Myung, Yun Soo; Moon, Taeyoon

2014-04-01

We study thermodynamic and classical instability of AdS black holes in fourth-order gravity. These include the BTZ black hole in new massive gravity, Schwarzschild-AdS black hole, and higher-dimensional AdS black holes in fourth-order gravity. All thermo-dynamic quantities which are computed using the Abbot-Deser-Tekin method are used to study thermodynamic instability of AdS black holes. On the other hand, we investigate the s-mode Gregory-Laflamme instability of the massive graviton propagating around the AdS black holes. We establish the connection between the thermodynamic instability and the GL instability of AdS black holes in fourth-order gravity. This shows that the Gubser-Mitra conjecture holds for AdS black holes found from fourth-order gravity.

Collapse and Nonlinear Instability of AdS Space with Angular Momentum

NASA Astrophysics Data System (ADS)

Choptuik, Matthew W.; Dias, Óscar J. C.; Santos, Jorge E.; Way, Benson

2017-11-01

We present a numerical study of rotational dynamics in AdS5 with equal angular momenta in the presence of a complex doublet scalar field. We determine that the endpoint of gravitational collapse is a Myers-Perry black hole for high energies and a hairy black hole for low energies. We investigate the time scale for collapse at low energies E , keeping the angular momenta J ∝E in anti-de Sitter (AdS) length units. We find that the inclusion of angular momenta delays the collapse time, but retains a t ˜1 /E scaling. We perturb and evolve rotating boson stars, and find that boson stars near AdS space appear stable, but those sufficiently far from AdS space are unstable. We find that the dynamics of the boson star instability depend on the perturbation, resulting either in collapse to a Myers-Perry black hole, or development towards a stable oscillating solution.

On information loss in AdS 3/CFT 2

DOE PAGES

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

2016-05-18

We discuss information loss from black hole physics in AdS 3, focusing on two sharp signatures infecting CFT 2 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 themore » behavior of correlators at times t ~S BH, the black hole entropy. This may resolve the exponential decay of correlators at late times in black hole backgrounds. By Borel resumming the 1/c expansion of exact examples, we explicitly identify ‘information-restoring’ effects from heavy states that should correspond to classical solutions in AdS 3. Lastly, our results suggest a line of inquiry towards a more precise formulation of the gravitational path integral in AdS 3.« less

Semiclassical Virasoro blocks from AdS 3 gravity

DOE PAGES

Hijano, Eliot; Kraus, Per; Perlmutter, Eric; ...

2015-12-14

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 AdS 3 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 AdS 3; thismore » approach highlights the chiral nature of Virasoro blocks. Finally, these techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.« less

EXACT S-MATRICES FOR AdS3/CFT2

NASA Astrophysics Data System (ADS)

Ahn, Changrim; Bombardelli, Diego

2013-12-01

We propose exact S-matrices for the AdS3/CFT2 duality between type IIB strings on AdS3×S3×M4 with M4 = S3×S1 or T4 and the corresponding two-dimensional conformal field theories. We fix the two-particle S-matrices on the basis of the symmetries su(1|1) and su(1|1)×su(1|1). A crucial justification comes from the derivation of the all-loop Bethe ansatz matching exactly the recent conjecture proposed by Babichenko et al. [J. High Energy Phys.1003, 058 (2010), arXiv:0912.1723 [hep-th

Minimal surfaces in AdS space and integrable systems

NASA Astrophysics Data System (ADS)

Burrington, Benjamin A.; Gao, Peng

2010-04-01

We consider the Pohlmeyer reduction for spacelike minimal area worldsheets in AdS5. The Lax pair for the reduced theory is found, and written entirely in terms of the A3 = D3 root system, generalizing the B2 affine Toda system which appears for the AdS4 string. For the B2 affine Toda system, we show that the area of the worlsheet is obtainable from the moduli space Kähler potential of a related Hitchin system. We also explore the Saveliev-Leznov construction for solutions of the B2 affine Toda system, and recover the rotationally symmetric solution associated to Painleve transcendent.

Financial and health literacy predict incident AD dementia and AD pathology

PubMed Central

Yu, Lei; Wilson, Robert S.; Schneider, Julie A.; Bennett, David A.; Boyle, Patricia A.

2017-01-01

Background Domain specific literacy is a multidimensional construct that requires multiple resources including cognitive and non-cognitive factors. Objective We test the hypothesis that domain specific literacy is associated with AD dementia and AD pathology after controlling for cognition. Methods Participants were community based older persons who completed a baseline literacy assessment, underwent annual clinical evaluations for up to 8 years and agreed to organ donation after death. Financial and health literacy was measured using 32 questions and cognition was measured using 19 tests. Annual diagnosis of AD dementia followed standard criteria. AD pathology was examined post-mortem by quantifying plaques and tangles. Cox models examined the association of literacy with incident AD dementia. Performance of model prediction for incident AD dementia was assessed using indices for integrated discrimination improvement and continuous net reclassification improvement. Linear regression models examined the independent association of literacy with AD pathology in autopsied participants. Results All 805 participants were free of dementia at baseline and 102 (12.7%) developed AD dementia during the follow-up. Lower literacy was associated with higher risk for incident AD dementia (p<0.001), and the association persisted after controlling for cognition (Hazard Ratio=1.50, p=0.004). The model including the literacy measure had better predictive performance than the one with demographics and cognition only. Lower literacy also was associated with higher burden of AD pathology after controlling for cognition (β=0.07, p=0.035). Conclusion Literacy predicts incident AD dementia and AD pathology in community-dwelling older persons, and the association is independent of traditional measures of cognition. PMID:28157101

What's the point? Hole-ography in Poincaré AdS

NASA Astrophysics Data System (ADS)

Espíndola, Ricardo; Güijosa, Alberto; Landetta, Alberto; Pedraza, Juan F.

2018-01-01

In the context of the AdS/CFT correspondence, we study bulk reconstruction of the Poincaré wedge of AdS_3 via hole-ography, i.e., in terms of differential entropy of the dual CFT_2. Previous work had considered the reconstruction of closed or open spacelike curves in global AdS, and of infinitely extended spacelike curves in Poincaré AdS that are subject to a periodicity condition at infinity. Working first at constant time, we find that a closed curve in Poincaré is described in the CFT by a family of intervals that covers the spatial axis at least twice. We also show how to reconstruct open curves, points and distances, and obtain a CFT action whose extremization leads to bulk points. We then generalize all of these results to the case of curves that vary in time, and discover that generic curves have segments that cannot be reconstructed using the standard hole-ographic construction. This happens because, for the nonreconstructible segments, the tangent geodesics fail to be fully contained within the Poincaré wedge. We show that a previously discovered variant of the hole-ographic method allows us to overcome this challenge, by reorienting the geodesics touching the bulk curve to ensure that they all remain within the wedge. Our conclusion is that all spacelike curves in Poincaré AdS can be completely reconstructed with CFT data, and each curve has in fact an infinite number of representations within the CFT.

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

Randomised controlled trial of high versus ad libitum water intake in patients with autosomal dominant polycystic kidney disease: rationale and design of the DRINK feasibility trial

PubMed Central

El-Damanawi, Ragada; Lee, Michael; Harris, Tess; Mader, Laura B; Bond, Simon; Pavey, Holly; Sandford, Richard N; Wilkinson, Ian B; Burrows, Alison; Woznowski, Przemyslaw; Ben-Shlomo, Yoav; Karet Frankl, Fiona E; Hiemstra, Thomas F

2018-01-01

Introduction Vasopressin stimulates cyst growth in autosomal dominant polycystic kidney disease (ADPKD) leading to enlarged kidneys, hypertension and renal failure. Vasopressin receptor blockade slows disease progression. Physiological suppression of vasopressin secretion through high water (HW) intake could achieve a similar effect, necessitating a definitive large-scale trial of HW intake in ADPKD. The objective of the DRINK trial is to answer the key design and feasibility questions required to deliver a successful definitive water intake trial. Methods and analysis We describe the design of a single-centre, open-label, prospective, randomised controlled trial. The "Determining feasibility of R andomisation to high vs. ad libitum water In take in Polycystic K idney Disease" (DRINK) trial aims to enrol 50 patients with ADPKD, over the age of 16 years with an estimated glomerular filtration rate (eGFR) ≥20 mL/min/1.73 m2. Participants will be randomised 1:1 to HW intake based on an individualised water intake prescription, or to ad libitum (AW) water intake. The HW group will aim for a dilute urine (urine osmolality ≤270 mOsm/kg) as a surrogate marker of vasopressin suppression, and those in the AW group will target more concentrated urine. Participants will have an 8-week treatment period, and will be seen at weeks 0, 2, 4 and 8, undergoing assessments of fluid status, renal function and serum and urine osmolalities. They will receive dietary advice, and self-monitor urine specific gravity and fluid intake. The trial employs smartphone technology to permit home monitoring and remote direct data capture. The primary feasibility end points are recruitment rate and separation between arms in measured urinary osmolality. Key secondary assessments include acceptability, adherence, health-related quality of life, acute effects of HW intake on measured (51Cr-EDTA) and eGFR and ADPKD-related pain. Ethics and dissemination Ethical approval was awarded by the

String in AdS black hole: A thermo field dynamic approach

NASA Astrophysics Data System (ADS)

Cantcheff, M. Botta; Gadelha, Alexandre L.; Marchioro, Dáfni F. Z.; Nedel, Daniel Luiz

2012-10-01

Based on Maldacena’s description of an eternal anti-de Sitter (AdS) black hole, we reassess the thermo field dynamics (TFD) formalism in the context of the AdS/CFT correspondence. The model studied here involves the maximally extended AdS-Schwarschild solution and two (noninteracting) copies of the conformal field theory (CFT) associated to the global AdS spacetime, along with an extension of the string by imposing natural gluing conditions in the horizon. We show that the gluing conditions in the horizon define a string boundary state which is identified with the TFD thermal vacuum, globally defined in the Kruskal extension of the AdS black hole. We emphasize the connection of this picture with unitary SU(1,1) TFD formulation, and we show that information about the bulk and the conformal boundary is present in the SU(1,1) parameters. Using the unitary SU(1,1) TFD formulation, a canonical prescription for calculating the world sheet real time thermal Green’s function is made, and the entropy associated with the entanglement of the two CFT’s is calculated.

Tweaking one-loop determinants in AdS3

NASA Astrophysics Data System (ADS)

Castro, Alejandra; Keeler, Cynthia; Szepietowski, Phillip

2017-10-01

We revisit the subject of one-loop determinants in AdS3 gravity via the quasi-normal mode method. Our goal is to evaluate a one-loop determinant with chiral boundary conditions for the metric field; chirality is achieved by imposing Dirichlet boundary conditions on certain components while others satisfy Neumann. Along the way, we give a generalization of the quasinormal mode method for stationary (non-static) thermal backgrounds, and propose a treatment for Neumann boundary conditions in this framework. We evaluate the graviton one-loop determinant on the Euclidean BTZ background with parity-violating boundary conditions (CSS), and find excellent agreement with the dual warped CFT. We also discuss a more general falloff in AdS3 that is related to two dimensional quantum gravity in lightcone gauge. The behavior of the ghost fields under both sets of boundary conditions is novel and we discuss potential interpretations.

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.

Continuous-spin mixed-symmetry fields in AdS(5)

NASA Astrophysics Data System (ADS)

Metsaev, R. R.

2018-05-01

Free mixed-symmetry continuous-spin fields propagating in AdS(5) space and flat R(4,1) space are studied. In the framework of a light-cone gauge formulation of relativistic dynamics, we build simple actions for such fields. The realization of relativistic symmetries on the space of light-cone gauge mixed-symmetry continuous-spin fields is also found. Interrelations between constant parameters entering the light-cone gauge actions and eigenvalues of the Casimir operators of space-time symmetry algebras are obtained. Using these interrelations and requiring that the field dynamics in AdS(5) be irreducible and classically unitary, we derive restrictions on the constant parameters and eigenvalues of the second-order Casimir operator of the algebra.

F-theory and AdS3/CFT2 (2, 0)

NASA Astrophysics Data System (ADS)

Couzens, Christopher; Martelli, Dario; Schäfer-Nameki, Sakura

2018-06-01

We continue to develop the program initiated in [1] of studying supersymmetric AdS3 backgrounds of F-theory and their holographic dual 2d superconformal field theories, which are dimensional reductions of theories with varying coupling. Imposing 2d N=(0,2) supersymmetry,wederivethegeneralconditionsonthegeometryforTypeIIB AdS3 solutions with varying axio-dilaton and five-form flux. Locally the compact part of spacetime takes the form of a circle fibration over an eight-fold Y_8^{τ } , which is elliptically fibered over a base \\tilde{M}_6 . We construct two classes of solutions given in terms of a product ansatz \\tilde{M}_6}=Σ × {M}_4 , where Σ is a complex curve and \\tilde{M}_4 is locally a Kähler surface. In the first class \\tilde{M}_4 is globally a Kähler surface and we take the elliptic fibration to vary non-trivially over either of these two factors, where in both cases the metrics on the total space of the elliptic fibrations are not Ricci-flat. In the second class the metric on the total space of the elliptic fibration over either curve or surface are Ricci-flat. This results in solutions of the type AdS3 × K3 × ℳ 5 τ , dual to 2d (0, 2) SCFTs, and AdS3 × S 3/Γ × CY 3, dual to 2d (0, 4) SCFTs, respectively. In all cases we compute the charges for the dual field theories with varying coupling and find agreement with the holographic results. We also show that solutions with enhanced 2d N=(2,2) supersymmetry must have constant axio-dilaton. Allowing the internal geometry to be non-compact leads to the most general class of Type IIB AdS5 solutions with varying axio-dilaton, i.e. F-theoretic solutions, that are dual to 4d N=1 SCFTs.

Stability of warped AdS3 vacua of topologically massive gravity

NASA Astrophysics Data System (ADS)

Anninos, Dionysios; Esole, Mboyo; Guica, Monica

2009-10-01

AdS3 vacua of topologically massive gravity (TMG) have been shown to be perturbatively unstable for all values of the coupling constant except the chiral point μl = 1. We study the possibility that the warped vacua of TMG, which exist for all values of μ, are stable under linearized perturbations. In this paper, we show that spacelike warped AdS3 vacua with Compère-Detournay boundary conditions are indeed stable in the range μl>3. This is precisely the range in which black hole solutions arise as discrete identifications of the warped AdS3 vacuum. The situation somewhat resembles chiral gravity: although negative energy modes do exist, they are all excluded by the boundary conditions, and the perturbative spectrum solely consists of boundary (pure large gauge) gravitons.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Zhi; Liao, Wenhua; Yang, Yuanyuan

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 anmore » 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

17 CFR 240.17Ad-4 - Applicability of §§ 240.17Ad-2, 240.17Ad-3 and 240.17Ad-6(a) (1) through (7) and (11).

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Applicability of §§ 240.17Ad-2, 240.17Ad-3 and 240.17Ad-6(a) (1) through (7) and (11). 240.17Ad-4 Section 240.17Ad-4 Commodity... Commission or the Office of the Comptroller of the Currency, prepare and maintain in its possession a...

17 CFR 240.17Ad-4 - Applicability of §§ 240.17Ad-2, 240.17Ad-3 and 240.17Ad-6(a) (1) through (7) and (11).

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Applicability of §§ 240.17Ad-2, 240.17Ad-3 and 240.17Ad-6(a) (1) through (7) and (11). 240.17Ad-4 Section 240.17Ad-4 Commodity... Commission or the Office of the Comptroller of the Currency, prepare and maintain in its possession a...

Faster eating rates are associated with higher energy intakes during an Ad libitum meal, higher BMI and greater adiposity among 4.5 year old children – Results from the GUSTO cohort

PubMed Central

Fogel, Anna; Goh, Ai Ting; Fries, Lisa R.; Sadananthan, Suresh Anand; Velan, S. Sendhil; Michael, Navin; Tint, Mya Thway; Fortier, Marielle Valerie; Chan, Mei Jun; Toh, Jia Ying; Chong, Yap-Seng; Tan, Kok Hian; Yap, Fabian; Shek, Lynette P.; Meaney, Michael J.; Broekman, Birit F.P.; Lee, Yung Seng; Godfrey, Keith M.; Chong, Mary Foong Fong; Forde, Ciarán Gerard

2017-01-01

Faster eating rates are associated with increased energy intake, but less is known about the relationship between children’s eating rate, food intake and adiposity. We examined whether children who eat faster consume more energy and whether this is associated with higher weight status and adiposity. We hypothesized that eating rate mediates the relationship between child weight and ad libitum energy intake. Children (N=386) from the Growing Up in Singapore towards Healthy Outcomes (GUSTO) cohort participated in a video-recorded ad libitum lunch at 4.5 years to measure acute energy intake. Videos were coded for three eating-behaviours (bites, chews and swallows) to derive a measure of eating rate (g/min). Body mass index (BMI) and anthropometric indices of adiposity were measured. A subset of children underwent MRI scanning (n=153) to measure abdominal subcutaneous and visceral adiposity. Children above/below the median eating rate were categorised as slower and faster eaters, and compared across body composition measures. There was a strong positive relationship between eating rate and energy intake (r=0.61, p<0.001) and a positive linear relationship between eating rate and children’s BMI status. Faster eaters consumed 75% more calories than slower eating children (Δ131 kcal, 95%CI [107.6, 154.4], p<0.001), and had higher whole-body (p<0.05) and subcutaneous abdominal adiposity (Δ118.3 cc; 95%CI [24.0, 212.7], p=0.014). Mediation analysis showed that eating rate mediates the link between child weight and energy intake during a meal (b=13.59, 95% CI [7.48, 21.83]). Children who ate faster had higher energy intake, and this was associated with increased BMIz and adiposity. PMID:28462734

Infrared realization of dS2 in AdS2

NASA Astrophysics Data System (ADS)

Anninos, Dionysios; Hofman, Diego M.

2018-04-01

We describe a two-dimensional geometry that smoothly interpolates between an asymptotically AdS2 geometry and the static patch of dS2. We find this ‘centaur’ geometry to be a solution of dilaton gravity with a specific class of potentials for the dilaton. We interpret the centaur geometry as a thermal state in the putative quantum mechanics dual to the AdS2 evolved with the global Hamiltonian. We compute the thermodynamic properties and observe that the centaur state has finite entropy and positive specific heat. The static patch is the infrared part of the centaur geometry. We discuss boundary observables sensitive to the static patch region.

QCD Condensates and Holographic Wilson Loops for Asymptotically AdS Spaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

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 anmore » 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.« less

Static Einstein-Maxwell Black Holes with No Spatial Isometries in AdS Space.

PubMed

Herdeiro, Carlos A R; Radu, Eugen

2016-11-25

We explicitly construct static black hole solutions to the fully nonlinear, D=4, Einstein-Maxwell-anti-de Sitter (AdS) equations that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon (section), but without isometries, and approach, asymptotically, global AdS spacetime. They are interpreted as bound states of a horizon with the Einstein-Maxwell-AdS solitons recently discovered, for appropriate boundary data. In sharp contrast to the uniqueness results for a Minkowski electrovacuum, the existence of these black holes shows that single, equilibrium, black hole solutions in an AdS electrovacuum admit an arbitrary multipole structure.

AdS 2 holographic dictionary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cvetic, Mirjam; Papadimitriou, Ioannis

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

AdS 2 holographic dictionary

DOE PAGES

Cvetic, Mirjam; Papadimitriou, Ioannis

2016-12-02

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

Witten diagrams revisited: the AdS geometry of conformal blocks

DOE PAGES

Hijano, Eliot; Kraus, Per; Perlmutter, Eric; ...

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

Half-BPS Wilson loop and AdS 2/CFT 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giombi, Simone; Roiban, Radu; Tseytlin, Arkady A.

Here, we study correlation functions of local operator insertions on the 1/2-BPS Wilson line in N=4 super Yang–Mills theory. These correlation functions are constrained by the 1d superconformal symmetry pre-served by the 1/2-BPS Wilson line and define a defect CFT 1 living on the line. At strong coupling, a set of elementary operator insertions with protected scaling dimensions correspond to fluctuations of the dual fundamental string in AdS 5×S 5 ending on the line at the boundary and can be thought of as light fields propagating on the AdS 2 worldsheet. We use AdS/CFT techniques to compute the tree-level AdSmore » 2 Witten diagrams describing the strong coupling limit of the four-point functions of the dual operator insertions. Using the OPE, we also extract the leading strong coupling corrections to the anomalous dimensions of the “two-particle” operators built out of elementary excitations. In the case of the circular Wilson loop, we match our results for the 4-point functions of a special type of scalar insertions to the prediction of localization to 2d Yang–Mills theory.« less

Half-BPS Wilson loop and AdS 2/CFT 1

DOE PAGES

Giombi, Simone; Roiban, Radu; Tseytlin, Arkady A.

2017-09-01

Here, we study correlation functions of local operator insertions on the 1/2-BPS Wilson line in N=4 super Yang–Mills theory. These correlation functions are constrained by the 1d superconformal symmetry pre-served by the 1/2-BPS Wilson line and define a defect CFT 1 living on the line. At strong coupling, a set of elementary operator insertions with protected scaling dimensions correspond to fluctuations of the dual fundamental string in AdS 5×S 5 ending on the line at the boundary and can be thought of as light fields propagating on the AdS 2 worldsheet. We use AdS/CFT techniques to compute the tree-level AdSmore » 2 Witten diagrams describing the strong coupling limit of the four-point functions of the dual operator insertions. Using the OPE, we also extract the leading strong coupling corrections to the anomalous dimensions of the “two-particle” operators built out of elementary excitations. In the case of the circular Wilson loop, we match our results for the 4-point functions of a special type of scalar insertions to the prediction of localization to 2d Yang–Mills theory.« less

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,…

Evaporation of large black holes in AdS: coupling to the evaporon

NASA Astrophysics Data System (ADS)

Rocha, Jorge V.

2008-08-01

Large black holes in an asymptotically AdS spacetime have a dual description in terms of approximately thermal states in the boundary CFT. The reflecting boundary conditions of AdS prevent such black holes from evaporating completely. On the other hand, the formulation of the information paradox becomes more stringent when a black hole is allowed to evaporate. In order to address the information loss problem from the AdS/CFT perspective we then need the boundary to become partially absorptive. We present a simple model that produces the necessary changes on the boundary by coupling a bulk scalar field to the evaporon, an external field propagating in one extra spatial dimension. The interaction is localized at the boundary of AdS and leads to partial transmission into the additional space. The transmission coefficient is computed in the planar limit and perturbatively in the coupling constant. Evaporation of the large black hole corresponds to cooling down the CFT by transferring energy to an external sector.

Hairy black holes and the endpoint of AdS4 charged superradiance

NASA Astrophysics Data System (ADS)

Dias, Óscar J. C.; Masachs, Ramon

2017-02-01

We construct hairy black hole solutions that merge with the anti-de Sitter (AdS4) Reissner-Nordström black hole at the onset of superradiance. These hairy black holes have, for a given mass and charge, higher entropy than the corresponding AdS4-Reissner-Nordström black hole. Therefore, they are natural candidates for the endpoint of the charged superradiant instability. On the other hand, hairy black holes never dominate the canonical and grand-canonical ensembles. The zero-horizon radius of the hairy black holes is a soliton (i.e. a boson star under a gauge transformation). We construct our solutions perturbatively, for small mass and charge, so that the properties of hairy black holes can be used to testify and compare with the endpoint of initial value simulations. We further discuss the near-horizon scalar condensation instability which is also present in global AdS4-Reissner-Nordström black holes. We highlight the different nature of the near-horizon and superradiant instabilities and that hairy black holes ultimately exist because of the non-linear instability of AdS.

Smooth causal patches for AdS black holes

NASA Astrophysics Data System (ADS)

Raju, Suvrat

2017-06-01

We review the paradox of low energy excitations of a black hole in anti-de Sitter space (AdS). An appropriately chosen unitary operator in the boundary theory can create a locally strong excitation near the black hole horizon, whose global energy is small as a result of the gravitational redshift. The paradox is that this seems to violate a general rule of statistical mechanics, which states that an operator with energy parametrically smaller than k T cannot create a significant excitation in a thermal system. When we carefully examine the position dependence of the boundary unitary operator that produces the excitation and the bulk observable necessary to detect the anomalously large effect, we find that they do not both fit in a single causal patch. This follows from a remarkable property of position-space AdS correlators that we establish explicitly and resolves the paradox in a generic state of the system, since no combination of observers can both create the excitation and observe its effect. As a special case of our analysis, we show how this resolves the "Born rule" paradox of Marolf and Polchinski [J. High Energy Phys. 01 (2016) 008, 10.1007/JHEP01(2016)008] and we verify our solution using an independent calculation. We then consider boundary states that are finely tuned to display a spontaneous excitation outside the causal patch of the infalling observer, and we propose a version of causal patch complementarity in AdS/CFT that resolves the paradox for such states as well.

Position space analysis of the AdS (in)stability problem

NASA Astrophysics Data System (ADS)

Dimitrakopoulos, Fotios V.; Freivogel, Ben; Lippert, Matthew; Yang, I.-Sheng

2015-08-01

We investigate whether arbitrarily small perturbations in global AdS space are generically unstable and collapse into black holes on the time scale set by gravitational interactions. We argue that current evidence, combined with our analysis, strongly suggests that a set of nonzero measure in the space of initial conditions does not collapse on this time scale. We perform an analysis in position space to study this puzzle, and our formalism allows us to directly study the vanishing-amplitude limit. We show that gravitational self-interaction leads to tidal deformations which are equally likely to focus or defocus energy, and we sketch the phase diagram accordingly. We also clarify the connection between gravitational evolution in global AdS and holographic thermalization.

Beyond AdS Space-times, New Holographic Correspondences and Applications

NASA Astrophysics Data System (ADS)

Ghodrati, Mahdis

The AdS/CFT correspondence conjectures a mathematical equivalence between string theories and gauge theories. In a particular limit it allows a description of strongly coupled conformal field theory via weakly coupled gravity. This feature has been used to gain insight into many condensed matter (CM) systems. However, to apply the duality in more physical scenarios, one needs to go beyond the usual AdS/CFT framework and extend the duality to non-AdS situations. To describe Lifshitz and hyperscaling violating (HSV) phenomena in CM one uses gauge fields on the gravity side which naturally realize the breaking of Lorentz invariance. These gravity constructions often contain naked singularities. In this thesis, we construct a resolution of the infra-red (IR) singularity of the HSV background. The idea is to add squared curvature terms to the Einstein-Maxwell dilaton action to build a flow from AdS4 in the ultra violate (UV) to an intermediating HSV region and then to an AdS2 x R 2 region in the IR. This general solution is free from the naked singularities and would be more appropriate for applications of HSV in physical systems. We also study the Schwinger effect by using the AdS/CFT duality. We present the phase diagrams of the Schwinger effect and also the "butterfly shaped-phase diagrams" of the entanglement entropy for four different confining supergravity backgrounds. Comparing different features of all of these diagrams could point out to a potential relation between the Schwinger effect and the entanglement entropy which could lead to a method of measuring entanglement entropy in the laboratory. Finally, we study the "new massive gravity" theory and the different black hole solutions it admits. We first present three different methods of calculating the conserved charges. Then, by calculating the on-shell Gibbs free energy we construct the Hawking-Page phase diagrams for different solutions in two thermodynamical ensembles. As the massive gravity models are

Quantum spectral curve for the η-deformed AdS5 × S5 superstring

NASA Astrophysics Data System (ADS)

Klabbers, Rob; van Tongeren, Stijn J.

2017-12-01

The spectral problem for the AdS5 ×S5 superstring and its dual planar maximally supersymmetric Yang-Mills theory can be efficiently solved through a set of functional equations known as the quantum spectral curve. We discuss how the same concepts apply to the η-deformed AdS5 ×S5 superstring, an integrable deformation of the AdS5 ×S5 superstring with quantum group symmetry. This model can be viewed as a trigonometric version of the AdS5 ×S5 superstring, like the relation between the XXZ and XXX spin chains, or the sausage and the S2 sigma models for instance. We derive the quantum spectral curve for the η-deformed string by reformulating the corresponding ground-state thermodynamic Bethe ansatz equations as an analytic Y system, and map this to an analytic T system which upon suitable gauge fixing leads to a Pμ system - the quantum spectral curve. We then discuss constraints on the asymptotics of this system to single out particular excited states. At the spectral level the η-deformed string and its quantum spectral curve interpolate between the AdS5 ×S5 superstring and a superstring on "mirror" AdS5 ×S5, reflecting a more general relationship between the spectral and thermodynamic data of the η-deformed string. In particular, the spectral problem of the mirror AdS5 ×S5 string, and the thermodynamics of the undeformed AdS5 ×S5 string, are described by a second rational limit of our trigonometric quantum spectral curve, distinct from the regular undeformed limit.

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

Transformations of asymptotically AdS hyperbolic initial data and associated geometric inequalities

NASA Astrophysics Data System (ADS)

Cha, Ye Sle; Khuri, Marcus

2018-01-01

We construct transformations which take asymptotically AdS hyperbolic initial data into asymptotically flat initial data, and which preserve relevant physical quantities. This is used to derive geometric inequalities in the asymptotically AdS hyperbolic setting from counterparts in the asymptotically flat realm, whenever a geometrically motivated system of elliptic equations admits a solution. The inequalities treated here relate mass, angular momentum, charge, and horizon area. Furthermore, new mass-angular momentum inequalities in this setting are conjectured and discussed.

Open string fluctuations in AdS space with and without torsion

NASA Astrophysics Data System (ADS)

Larsen, A. L.; Lomholt, M. A.

2003-09-01

The equations of motion and boundary conditions for the fluctuations around a classical open string, in a curved space-time with torsion, are considered in compact and world-sheet covariant form. The rigidly rotating open strings in anti de Sitter space with and without torsion are investigated in detail. By carefully analyzing the tangential fluctuations at the boundary, we show explicitly that the physical fluctuations (which at the boundary are combinations of normal and tangential fluctuations) are finite, even though the world-sheet is singular there. The divergent 2-curvature thus seems less dangerous than expected in these cases. The general formalism can be straightforwardly used also to study the (bosonic part of the) fluctuations around the closed strings, recently considered in connection with the AdS/conformal field theory duality, on AdS5×S5 and AdS3×S3×T4.

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.

Fermionic currents in AdS spacetime with compact dimensions

NASA Astrophysics Data System (ADS)

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

2017-09-01

We derive a closed expression for the vacuum expectation value (VEV) of the fermionic current density in a (D +1 )-dimensional locally AdS spacetime with an arbitrary number of toroidally compactified Poincaré spatial dimensions and in the presence of a constant gauge field. The latter can be formally interpreted in terms of a magnetic flux treading the compact dimensions. In the compact subspace, the field operator obeys quasiperiodicity conditions with arbitrary phases. The VEV of the charge density is zero and the current density has nonzero components along the compact dimensions only. They are periodic functions of the magnetic flux with the period equal to the flux quantum and tend to zero on the AdS boundary. Near the horizon, the effect of the background gravitational field is small and the leading term in the corresponding asymptotic expansion coincides with the VEV for a massless field in the locally Minkowski bulk. Unlike the Minkowskian case, in the system consisting of an equal number of fermionic and scalar degrees of freedom, with same masses, charges and phases in the periodicity conditions, the total current density does not vanish. In these systems, the leading divergences in the scalar and fermionic contributions on the horizon are canceled and, as a consequence of that, the charge flux, integrated over the coordinate perpendicular to the AdS boundary, becomes finite. We show that in odd spacetime dimensions the fermionic fields realizing two inequivalent representations of the Clifford algebra and having equal phases in the periodicity conditions give the same contribution to the VEV of the current density. Combining the contributions from these fields, the current density in odd-dimensional C -,P - and T -symmetric models are obtained. As an application, we consider the ground state current density in curved carbon nanotubes described in terms of a (2 +1 )-dimensional effective Dirac model.

Symmetry operators of Killing spinors and superalgebras in AdS5

NASA Astrophysics Data System (ADS)

Ertem, Ümit

2016-04-01

We construct the first-order symmetry operators of Killing spinor equation in terms of odd Killing-Yano forms. By modifying the Schouten-Nijenhuis bracket of Killing-Yano forms, we show that the symmetry operators of Killing spinors close into an algebra in AdS5 spacetime. Since the symmetry operator algebra of Killing spinors corresponds to a Jacobi identity in extended Killing superalgebras, we investigate the possible extensions of Killing superalgebras to include higher-degree Killing-Yano forms. We found that there is a superalgebra extension but no Lie superalgebra extension of the Killing superalgebra constructed out of Killing spinors and odd Killing-Yano forms in AdS5 background.

Functional determinants of radial operators in AdS2

DOE PAGES

Aguilera-Damia, Jeremías; Faraggi, Alberto; Zayas, Leopoldo Pando; ...

2018-06-01

We study the zeta-function regularization of functional determinants of Laplace and Dirac-type operators in two-dimensional Euclidean AdS2 space. More specifically, we consider the ratio of determinants between an operator in the presence of background fields with circular symmetry and the free operator in which the background fields are absent. By Fourier-transforming the angular dependence, one obtains an infinite number of one-dimensional radial operators, the determinants of which are easy to compute. The summation over modes is then treated with care so as to guarantee that the result coincides with the two-dimensional zeta-function formalism. The method relies on some well-known techniquesmore » to compute functional determinants using contour integrals and the construction of the Jost function from scattering theory. Our work generalizes some known results in flat space. The extension to conformal AdS2 geometries is also considered. We provide two examples, one bosonic and one fermionic, borrowed from the spectrum of fluctuations of the holographic 1/4-BPS latitude Wilson loop.« less

Functional determinants of radial operators in AdS 2

NASA Astrophysics Data System (ADS)

Aguilera-Damia, Jeremías; Faraggi, Alberto; Zayas, Leopoldo Pando; Rathee, Vimal; Silva, Guillermo A.

2018-06-01

We study the zeta-function regularization of functional determinants of Laplace and Dirac-type operators in two-dimensional Euclidean AdS 2 space. More specifically, we consider the ratio of determinants between an operator in the presence of background fields with circular symmetry and the free operator in which the background fields are absent. By Fourier-transforming the angular dependence, one obtains an infinite number of one-dimensional radial operators, the determinants of which are easy to compute. The summation over modes is then treated with care so as to guarantee that the result coincides with the two-dimensional zeta-function formalism. The method relies on some well-known techniques to compute functional determinants using contour integrals and the construction of the Jost function from scattering theory. Our work generalizes some known results in flat space. The extension to conformal AdS 2 geometries is also considered. We provide two examples, one bosonic and one fermionic, borrowed from the spectrum of fluctuations of the holographic 1/4 -BPS latitude Wilson loop.

The AdS3 propagator and the fate of locality

NASA Astrophysics Data System (ADS)

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

2018-04-01

We recently used Virasoro symmetry considerations to propose an exact formula for a bulk proto-field ϕ in AdS3. In this paper we study the propagator < ϕϕ>. We show that many techniques from the study of conformal blocks can be generalized to compute it, including the semiclassical monodromy method and both forms of the Zamolodchikov recursion relations. When the results from recursion are expanded at large central charge, they match gravitational perturbation theory for a free scalar field coupled to gravity in our chosen gauge. We find that although the propagator is finite and well-defined at long distances, its perturbative expansion in {G}_N=3/2c exhibits UV/IR mixing effects. If we nevertheless interpret < ϕϕ> as a probe of bulk locality, then when {G}_{N{m}_{φ }}≪ 1 locality breaks down at the new short-distance scale {σ}_{\\ast}˜ √[4]{G_N{R}_{AdS}^3} . For ϕ with very large bulk mass, or at small central charge, bulk locality fails at the AdS length scale. In all cases, locality `breakdown' manifests as singularities or branch cuts at spacelike separation arising from non-perturbative quantum gravitational effects.

Euclidean Wilson loops and minimal area surfaces in lorentzian AdS 3

DOE PAGES

Irrgang, Andrew; Kruczenski, Martin

2015-12-14

The AdS/CFT correspondence relates Wilson loops in N=4 SYM theory to minimal area surfaces in AdS 5 × S 5 space. If the Wilson loop is Euclidean and confined to a plane (t, x) then the dual surface is Euclidean and lives in Lorentzian AdS 3 c AdS 5. In this paper we study such minimal area surfaces generalizing previous results obtained in the Euclidean case. Since the surfaces we consider have the topology of a disk, the holonomy of the flat current vanishes which is equivalent to the condition that a certain boundary Schrödinger equation has all its solutionsmore » anti-periodic. If the potential for that Schrödinger equation is found then reconstructing the surface and finding the area become simpler. In particular we write a formula for the Area in terms of the Schwarzian derivative of the contour. Finally an infinite parameter family of analytical solutions using Riemann Theta functions is described. In this case, both the area and the shape of the surface are given analytically and used to check the previous results.« less

Holographic Rényi entropy in AdS3/LCFT2 correspondence

NASA Astrophysics Data System (ADS)

Chen, Bin; Song, Feng-yan; Zhang, Jia-ju

2014-03-01

The recent study in AdS3/CFT2 correspondence shows that the tree level contribution and 1-loop correction of holographic Rényi entanglement entropy (HRE) exactly match the direct CFT computation in the large central charge limit. This allows the Rényi entanglement entropy to be a new window to study the AdS/CFT correspondence. In this paper we generalize the study of Rényi entanglement entropy in pure AdS3 gravity to the massive gravity theories at the critical points. For the cosmological topological massive gravity (CTMG), the dual conformal field theory (CFT) could be a chiral conformal field theory or a logarithmic conformal field theory (LCFT), depending on the asymptotic boundary conditions imposed. In both cases, by studying the short interval expansion of the Rényi entanglement entropy of two disjoint intervals with small cross ratio x, we find that the classical and 1-loop HRE are in exact match with the CFT results, up to order x 6. To this order, the difference between the massless graviton and logarithmic mode can be seen clearly. Moreover, for the cosmological new massive gravity (CNMG) at critical point, which could be dual to a logarithmic CFT as well, we find the similar agreement in the CNMG/LCFT correspondence. Furthermore we read the 2-loop correction of graviton and logarithmic mode to HRE from CFT computation. It has distinct feature from the one in pure AdS3 gravity.

Boundary stress tensor and asymptotically AdS3 non-Einstein spaces at the chiral point

NASA Astrophysics Data System (ADS)

Giribet, Gaston; Goya, Andrés; Leston, Mauricio

2011-09-01

Chiral gravity admits asymptotically AdS3 solutions that are not locally equivalent to AdS3; meaning that solutions do exist which, while obeying the strong boundary conditions usually imposed in general relativity, happen not to be Einstein spaces. In topologically massive gravity (TMG), the existence of non-Einstein solutions is particularly connected to the question about the role played by complex saddle points in the Euclidean path integral. Consequently, studying (the existence of) nonlocally AdS3 solutions to chiral gravity is relevant to understanding the quantum theory. Here, we discuss a special family of nonlocally AdS3 solutions to chiral gravity. In particular, we show that such solutions persist when one deforms the theory by adding the higher-curvature terms of the so-called new massive gravity. Moreover, the addition of higher-curvature terms to the gravity action introduces new nonlocally AdS3 solutions that have no analogues in TMG. Both stationary and time-dependent, axially symmetric solutions that asymptote AdS3 space without being locally equivalent to it appear. Defining the boundary stress tensor for the full theory, we show that these non-Einstein geometries have associated vanishing conserved charges.

A universal counting of black hole microstates in AdS4

NASA Astrophysics Data System (ADS)

Azzurli, Francesco; Bobev, Nikolay; Crichigno, P. Marcos; Min, Vincent S.; Zaffaroni, Alberto

2018-02-01

Many three-dimensional N=2 SCFTs admit a universal partial topological twist when placed on hyperbolic Riemann surfaces. We exploit this fact to derive a universal formula which relates the planar limit of the topologically twisted index of these SCFTs and their three-sphere partition function. We then utilize this to account for the entropy of a large class of supersymmetric asymptotically AdS4 magnetically charged black holes in M-theory and massive type IIA string theory. In this context we also discuss novel AdS2 solutions of eleven-dimensional supergravity which describe the near horizon region of large new families of supersymmetric black holes arising from M2-branes wrapping Riemann surfaces.

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)

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

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.

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

NASA Astrophysics Data System (ADS)

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

1992-12-01

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.

Proper temperature of the Schwarzschild AdS black hole revisited

NASA Astrophysics Data System (ADS)

Eune, Myungseok; Kim, Wontae

2017-10-01

The Unruh temperature calculated by using the global embedding of the Schwarzschild AdS spacetime into the Minkowski spacetime was identified with the local proper temperature; however, it became imaginary in a certain region outside the event horizon. So, the temperature was assumed to be zero of non-thermal radiation for that region. In this work, we revisit this issue in an exactly soluble two-dimensional Schwarzschild AdS black hole and present an alternative resolution to this problem in terms of the Tolman's procedure. However, the process appears to be non-trivial in the sense that the original procedure assuming the traceless energy-momentum tensor should be extended in such a way that it should cover the non-vanishing case of the energy-momentum tensor in the presence of the trace anomaly. Consequently, we show that the proper temperature turns out to be real everywhere outside the event horizon without any imaginary value, in particular, it vanishes at both the horizon and the asymptotic infinity.

Integrability of the Ad{{S}_{5}}\\times {{S}^{5}} superstring and its deformations

NASA Astrophysics Data System (ADS)

van Tongeren, Stijn J.

2014-10-01

This article reviews the application of integrability to the spectral problem of strings on Ad{{S}5}× {{S}5} and its deformations. We begin with a pedagogical introduction to integrable field theories culminating in the description of their finite-volume spectra through the thermodynamic Bethe ansatz (TBA). Next, we apply these ideas to the Ad{{S}5}× {{S}5} string and in later sections discuss how to account for particular integrable deformations. Through the AdS/CFT correspondence this gives an exact description of anomalous scaling dimensions of single trace operators in planar N=4 supersymmetry Yang-Mills theory, its ‘orbifolds’, and β and γ-deformed supersymmetric Yang-Mills theory. We also touch upon some subtleties arising in these deformed theories. Furthermore, we consider complex excited states (bound states) in the su(2) sector and give their TBA description. Finally we discuss the TBA for a quantum deformation of the Ad{{S}5}× {{S}5} superstring S-matrix, with close relations to among others Pohlmeyer reduced string theory, and briefly indicate more recent developments in this area.

On supersymmetric AdS6 solutions in 10 and 11 dimensions

NASA Astrophysics Data System (ADS)

Gutowski, J.; Papadopoulos, G.

2017-12-01

We prove a non-existence theorem for smooth, supersymmetric, warped AdS 6 solutions with connected, compact without boundary internal space in D = 11 and (massive) IIA supergravities. In IIB supergravity we show that if such AdS 6 solutions exist, then the NSNS and RR 3-form fluxes must be linearly independent and certain spinor bilinears must be appropriately restricted. Moreover we demonstrate that the internal space admits an so(3) action which leaves all the fields invariant and for smooth solutions the principal orbits must have co-dimension two. We also describe the topology and geometry of internal spaces that admit such a so(3) action and show that there are no solutions for which the internal space has topology F × S 2, where F is an oriented surface.

Digital Quantum Simulation of Minimal AdS /CFT

NASA Astrophysics Data System (ADS)

García-Álvarez, L.; Egusquiza, I. L.; Lamata, L.; del Campo, A.; Sonner, J.; Solano, E.

2017-07-01

We propose the digital quantum simulation of a minimal AdS /CFT model in controllable quantum platforms. We consider the Sachdev-Ye-Kitaev model describing interacting Majorana fermions with randomly distributed all-to-all couplings, encoding nonlocal fermionic operators onto qubits to efficiently implement their dynamics via digital techniques. Moreover, we also give a method for probing nonequilibrium dynamics and the scrambling of information. Finally, our approach serves as a protocol for reproducing a simplified low-dimensional model of quantum gravity in advanced quantum platforms as trapped ions and superconducting circuits.

Multi-Skyrmions on AdS2 × S2, rational maps and popcorn transitions

NASA Astrophysics Data System (ADS)

Canfora, Fabrizio; Tallarita, Gianni

2017-08-01

By combining two different techniques to construct multi-soliton solutions of the (3 + 1)-dimensional Skyrme model, the generalized hedgehog and the rational map ansatz, we find multi-Skyrmion configurations in AdS2 ×S2. We construct Skyrmionic multi-layered configurations such that the total Baryon charge is the product of the number of kinks along the radial AdS2 direction and the degree of the rational map. We show that, for fixed total Baryon charge, as one increases the charge density on ∂ (AdS2 ×S2) , it becomes increasingly convenient energetically to have configurations with more peaks in the radial AdS2 direction but a lower degree of the rational map. This has a direct relation with the so-called holographic popcorn transitions in which, when the charge density is high, multi-layered configurations with low charge on each layer are favored over configurations with few layers but with higher charge on each layer. The case in which the geometry is M2 ×S2 can also be analyzed.

Topological terms, AdS2 n gravity, and renormalized entanglement entropy of holographic CFTs

NASA Astrophysics Data System (ADS)

Anastasiou, Giorgos; Araya, Ignacio J.; Olea, Rodrigo

2018-05-01

We extend our topological renormalization scheme for entanglement entropy to holographic CFTs of arbitrary odd dimensions in the context of the AdS /CFT correspondence. The procedure consists in adding the Chern form as a boundary term to the area functional of the Ryu-Takayanagi minimal surface. The renormalized entanglement entropy thus obtained can be rewritten in terms of the Euler characteristic and the AdS curvature of the minimal surface. This prescription considers the use of the replica trick to express the renormalized entanglement entropy in terms of the renormalized gravitational action evaluated on the conically singular replica manifold extended to the bulk. This renormalized action is obtained in turn by adding the Chern form as the counterterm at the boundary of the 2 n -dimensional asymptotically AdS bulk manifold. We explicitly show that, up to next-to-leading order in the holographic radial coordinate, the addition of this boundary term cancels the divergent part of the entanglement entropy. We discuss possible applications of the method for studying CFT parameters like central charges.

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

Closed Timelike Curves in (2+1)-AdS Gravity

NASA Astrophysics Data System (ADS)

Valtancoli, P.

We build the (2+1)-AdS gravity generalization of the Gott time machine using a first-order formalism for solving the scattering of point sources. The two-body dynamics is solved by two invariant masses, whose difference is simply related to the total angular momentum of the system. We show how to build a time machine when at least one of the two invariant masses is no more real but acquires an imaginary part.

Stochastic quantization of conformally coupled scalar in AdS

NASA Astrophysics Data System (ADS)

Jatkar, Dileep P.; Oh, Jae-Hyuk

2013-10-01

We explore the relation between stochastic quantization and holographic Wilsonian renormalization group flow further by studying conformally coupled scalar in AdS d+1. We establish one to one mapping between the radial flow of its double trace deformation and stochastic 2-point correlation function. This map is shown to be identical, up to a suitable field re-definition of the bulk scalar, to the original proposal in arXiv:1209.2242.

Exploring the bulk in AdS /CFT : A covariant approach

NASA Astrophysics Data System (ADS)

Engelhardt, Netta

2017-03-01

I propose a general, covariant way of defining when one region is "deeper in the bulk" than another. This definition is formulated outside of an event horizon (or in the absence thereof) in generic geometries; it may be applied to both points and surfaces, and it may be used to compare the depth of bulk points or surfaces relative to a particular boundary subregion or relative to the entire boundary. Using the recently proposed "light-cone cut" formalism, the comparative depth between two bulk points can be determined from the singularity structure of Lorentzian correlators in the dual field theory. I prove that, by this definition, causal wedges of progressively larger regions probe monotonically deeper in the bulk. The definition furthermore matches expectations in pure AdS and in static AdS black holes with isotropic spatial slices, where a well-defined holographic coordinate exists. In terms of holographic renormalization group flow, this new definition of bulk depth makes contact with coarse graining over both large distances and long time scales.

Plasma Cortisol Levels in Response to a Cold Pressor Test Did Not Predict Appetite or Ad Libitum Test Meal Intake in Obese Women

PubMed Central

Geliebter, Allan; Gibson, Charlisa D.; Hernandez, Dominica B.; Atalayer, Deniz; Kwon, Anne; Lee, Michelle I; Mehta, Nandini; Phair, Donna; Gluck, Marci E.

2012-01-01

Heightened cortisol response to stress due to hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis may stimulate appetite and food intake. In this study, we assessed cortisol responsivity to a cold pressor test (CPT) as well as appetite ratings and subsequent test meal intake (TMI) in obese women. Following an overnight fast on two counterbalanced days, 20 obese women immersed their non-dominant hand for 2 min in ice water (CPT) or warm water (WW) as a control. Plasma cortisol (ng/ml), heart rate, and blood pressure, as well as ratings of stress, pain, and appetite, were serially acquired. An ad libitum liquid meal was offered at 45 min and intake measured covertly. Fasting cortisol was higher at 15 min (mean peak cortisol) following the CPT compared to WW. Higher stress was reported at 2 and 15 min for the CPT compared to WW. Pain, an indirect marker of the acute stress, systolic and diastolic blood pressure increased following the CPT at 2 min compared to WW Hunger decreased after the CPT at 2 and 15 min, and desire to eat ratings were lower following CPT compared to WW . Subjects did not have greater test meal intake (TMI) following CPT compared to WW. There was also no significant relationship between cortisol levels following stress and TMI, indicating that cortisol did not predict subsequent intake in obese women. PMID:22983369

Small black holes in global AdS spacetime

NASA Astrophysics Data System (ADS)

Jokela, Niko; Pönni, Arttu; Vuorinen, Aleksi

2016-04-01

We study the properties of two-point functions and quasinormal modes in a strongly coupled field theory holographically dual to a small black hole in global anti-de Sitter spacetime. Our results are seen to smoothly interpolate between known limits corresponding to large black holes and thermal AdS space, demonstrating that the Son-Starinets prescription works even when there is no black hole in the spacetime. Omitting issues related to the internal space, the results can be given a field theory interpretation in terms of the microcanonical ensemble, which provides access to energy densities forbidden in the canonical description.

Effect of a High-Protein, High-Fiber Beverage Preload on Subjective Appetite Ratings and Subsequent Ad Libitum Energy Intake in Overweight Men and Women: A Randomized, Double-Blind Placebo-Controlled, Crossover Study.

PubMed

Sharafi, Mastaneh; Alamdari, Nima; Wilson, Michael; Leidy, Heather J; Glynn, Erin L

2018-06-01

Dietary protein and fiber have been shown to independently improve subjective measures of appetite control. The aim of this study was to determine the acute effects of a high-protein, high-fiber (HP/HFb) beverage taken as a preload compared with an isocaloric lower-protein, lower-fiber (LP/LFb) placebo beverage on subjective appetite ratings and subsequent energy intake at an ad libitum meal in healthy adults. A total of 50 overweight/obese men and women [ n  = 25 men, 25 women; age 30 ± 2 y; body mass index (BMI) 29.6 ± 0.3 kg/m 2 ] received a 160 kcal HP/HFb beverage containing 17 g protein and 6 g fiber on one occasion and an isocaloric LP/LFb placebo beverage containing 1 g protein and 3 g fiber on another occasion in a randomized, double-blind, crossover design. Thirty min after consumption of the beverage preload, an ad libitum pizza meal was provided to be consumed over a 30-min period. Visual analog scales (VAS) were used to assess subjective appetite ratings throughout the testing period. The Revised Restraint Scale (RRS) was used to classify participants as restrained or unrestrained eaters. HP/HFb led to greater reductions in postprandial desire to eat and hunger compared with LP/LFb (both, P  < 0.05) but did not significantly affect postprandial fullness or prospective food consumption. Subsequent meal energy intake tended to be lower after HP/HFb compared with LP/LFb ( P  = 0.09). A subanalysis showed lower energy intake after HP/HFb in older participants (≥25 y) compared with LP/LFb, which was not observed in the younger participants (<25 y). Compared with LP/LFb, a HP/HFb beverage preload reduced hunger, desire to eat, and tended to reduce subsequent food intake. Dietary restraint and age appear to influence subsequent energy intake and should be taken into account when designing nutrition interventions for weight reduction and/or maintenance. This trial was registered at clinicaltrials.gov as NCT02979717.

Constant curvature black holes in Einstein AdS gravity: Euclidean action and thermodynamics

NASA Astrophysics Data System (ADS)

Guilleminot, Pablo; Olea, Rodrigo; Petrov, Alexander N.

2018-03-01

We compute the Euclidean action for constant curvature black holes (CCBHs), as an attempt to associate thermodynamic quantities to these solutions of Einstein anti-de Sitter (AdS) gravity. CCBHs are gravitational configurations obtained by identifications along isometries of a D -dimensional globally AdS space, such that the Riemann tensor remains constant. Here, these solutions are interpreted as extended objects, which contain a (D -2 )-dimensional de-Sitter brane as a subspace. Nevertheless, the computation of the free energy for these solutions shows that they do not obey standard thermodynamic relations.

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

PubMed Central

Ma, Chunqi; Taves, Matthew D.; Soma, Kiran K.; Mufson, Elliott J.

2014-01-01

Decreases in testosterone (T) and 17β-oestradiol (E2) are associated with an increased risk for Alzheimer's disease (AD), which has been attributed to an increase in beta amyloid (Aβ) and tau pathologic lesions. While recent studies have used transgenic animal models to test the effects of sex steroid manipulations on AD-like pathology, virtually 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 T and E2 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 non-transgenic (ntg) mice. We report for the first time that circulating and brain T levels significantly increase in male 3xTgAD mice with age, but without changes in AR-immunoreactive (ir) cell number in either the hippocampal CA1 or medial amygdala. The age-related increase in hippocampal T levels correlated positively with increases in the conformational tau isoform, Alz50. These data suggest that the over-expression of human tau may up regulate the hypothalamic-pituitary-gonadal axis in these mice. Although circulating and brain E2 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. Further, E2 levels were significantly higher in the hippocampus than in serum, suggesting local production of E2. 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. PMID:22889357

Entanglement entropy of AdS5 × S5 with massive flavors

NASA Astrophysics Data System (ADS)

Hu, Sen; Wu, Guozhen

2018-01-01

We consider backreacted AdS5 × S5 coupled with Nf massive flavors introduced by D7 branes. The backreacted geometry is in the Veneziano limit with fixed Nf/Nc. By dividing one of the directions into a line segment with length l, we get two subspaces. Then we calculate the entanglement entropy between them. With the method of [I. R. Klebanov, D. Kutasov and A. Murugan, Nucl. Phys. B 796, 274 (2008)], we are able to find the cut-off independent part of the entanglement entropy and finally find that this geometry shows no confinement/deconfinement phase transition at zero temperature from the holographic entanglement entropy point of view similar to the case in pure AdS5 × S5.

AdS black disk model for small-x DIS

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

2011-05-23

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, F{sub T}{approx}F{sub L}{approx}{sup -}{omega}, where {omega} is related to the expansion rate of the black disk with energy. Furthermore, the ratio F{sub L}/F{sub T} is given by the universal value (1+{omega}/3+{omega}), independently of the target.

The Tetrahedral Zamolodchikov Algebra and the {AdS_5× S^5} S-matrix

NASA Astrophysics Data System (ADS)

Mitev, Vladimir; Staudacher, Matthias; Tsuboi, Zengo

2017-08-01

The S-matrix of the {AdS_5× S^5} string theory is a tensor product of two centrally extended su{(2|2)\\ltimes R^2 S-matrices, each of which is related to the R-matrix of the Hubbard model. The R-matrix of the Hubbard model was first found by Shastry, who ingeniously exploited the fact that, for zero coupling, the Hubbard model can be decomposed into two XX models. In this article, we review and clarify this construction from the AdS/CFT perspective and investigate the implications this has for the {AdS_5× S^5} S-matrix.

Partition functions with spin in AdS2 via quasinormal mode methods

DOE PAGES

Keeler, Cynthia; Lisbão, Pedro; Ng, Gim Seng

2016-10-12

We extend the results of [1], computing one loop partition functions for massive fields with spin half in AdS 2 using the quasinormal mode method proposed by Denef, Hartnoll, and Sachdev [2]. We find the finite representations of SO(2,1) for spin zero and spin half, consisting of a highest weight state |hi and descendants with non-unitary values of h. These finite representations capture the poles and zeroes of the one loop determinants. Together with the asymptotic behavior of the partition functions (which can be easily computed using a large mass heat kernel expansion), these are sufficient to determine the fullmore » answer for the one loop determinants. We also discuss extensions to higher dimensional AdS 2n and higher spins.« less

Thermodynamics and phase transition of charged AdS black holes with a global monopole

NASA Astrophysics Data System (ADS)

Deng, Gao-Ming; Fan, Jinbo; Li, Xinfei; Huang, Yong-Chang

2018-01-01

Thermodynamical properties of charged AdS black holes with a global monopole still remain obscure. In this paper, we investigate the thermodynamics and phase transition of the black holes in the extended phase space. It is shown that thermodynamical quantities of the black holes exhibit an interesting dependence on the internal global monopole, and they perfectly satisfy both the first law of thermodynamics and Smarr relation. Furthermore, analysis of the local and the global thermodynamical stability manifests that the charged AdS black hole undergoes an elegant phase transition at critical point. Of special interest, critical behaviors of the black holes resemble a Van der Waals liquid-gas system. Our results not only reveal the effect of a global monopole on thermodynamics of AdS black holes, but also further support that Van der Waals-like behavior of the black holes is a universal phenomenon.

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

2016-01-05

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.

Supergravity backgrounds for deformations of AdS n × S n supercoset string models

DOE PAGES

Lunin, O.; Roiban, R.; Tseytlin, A. A.

2014-12-11

We considermore » type IIB supergravity backgrounds corresponding to the deformed AdS n × S n × T 10 - 2 n supercoset string models of the type constructed in arXiv:1309.5850[2] which depend on one deformation parameter κ. In AdS 2 × S 2 case we find that the deformed metric can be extended to a full supergravity solution with non-trivial dilaton, RR scalar and RR 5-form strength. The solution depends on a free parameter a that should be chosen as a particular function of κ to correspond to the deformed supercoset model. In AdS 3 × S 3 case the full solution supported by the dilaton, RR scalar and RR 3-form strength exists only in the two special cases, a = 0 and a = 1 . We conjecture that there may be a more general one-parameter solution supported by several RR fields that for particular a = a ( κ ) corresponds to the supercoset model. In the most complicated deformed AdS 5 × S 5 case we were able to find only the expressions for the dilaton and the RR scalar. The full solution is likely to be supported by a combination of the 5-form and 3-form field strengths. We comment on the singularity structure of the resulting metric and exact dilaton field.« less

Supergravity backgrounds for deformations of AdS n × S n supercoset string models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lunin, O.; Roiban, R.; Tseytlin, A. A.

We considermore » type IIB supergravity backgrounds corresponding to the deformed AdS n × S n × T 10 - 2 n supercoset string models of the type constructed in arXiv:1309.5850[2] which depend on one deformation parameter κ. In AdS 2 × S 2 case we find that the deformed metric can be extended to a full supergravity solution with non-trivial dilaton, RR scalar and RR 5-form strength. The solution depends on a free parameter a that should be chosen as a particular function of κ to correspond to the deformed supercoset model. In AdS 3 × S 3 case the full solution supported by the dilaton, RR scalar and RR 3-form strength exists only in the two special cases, a = 0 and a = 1 . We conjecture that there may be a more general one-parameter solution supported by several RR fields that for particular a = a ( κ ) corresponds to the supercoset model. In the most complicated deformed AdS 5 × S 5 case we were able to find only the expressions for the dilaton and the RR scalar. The full solution is likely to be supported by a combination of the 5-form and 3-form field strengths. We comment on the singularity structure of the resulting metric and exact dilaton field.« less

The generalization of charged AdS black hole specific volume and number density

NASA Astrophysics Data System (ADS)

Wang, Zi-Liang; He, Miao; Fang, Chao; Sun, Dao-Quan; Deng, Jian-Bo

2017-04-01

In this paper, by proposing a generalized specific volume, we restudy the P- V criticality of charged AdS black holes in the extended phase space. The results show that most of the previous conclusions can be generalized without change, but the ratio {\\tilde{ρ }}_c should be 3 {\\tilde{α }}/16 in general case. Further research on the thermodynamical phase transition of black hole leads us to a natural interpretation of our assumption, and more black hole properties can be generalized. Finally, we study the number density for charged AdS black hole in higher dimensions, the results show the necessity of our assumption.

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

Complexity of the AdS soliton

NASA Astrophysics Data System (ADS)

Reynolds, Alan P.; Ross, Simon F.

2018-05-01

We consider the holographic complexity conjectures in the context of the AdS soliton, which is the holographic dual of the ground state of a field theory on a torus with antiperiodic boundary conditions for fermions on one cycle. The complexity is a non-trivial function of the size of the circle with antiperiodic boundary conditions, which sets an IR scale in the dual geometry. We find qualitative differences between the calculations of complexity from spatial volume and action (CV and CA). In the CV calculation, the complexity for antiperiodic boundary conditions is smaller than for periodic, and decreases monotonically with increasing IR scale. In the CA calculation, the complexity for antiperiodic boundary conditions is larger than for periodic, and initially increases with increasing IR scale, eventually decreasing to zero as the IR scale becomes of order the UV cutoff. We compare these results to a simple calculation for free fermions on a lattice, where we find the complexity for antiperiodic boundary conditions is larger than for periodic.

Higher protein diets consumed ad libitum improve cardiovascular risk markers in children of overweight parents from eight European countries.

PubMed

Damsgaard, Camilla T; Papadaki, Angeliki; Jensen, Signe M; Ritz, Christian; Dalskov, Stine-Mathilde; Hlavaty, Petr; Saris, Wim H M; Martinez, J Alfredo; Handjieva-Darlenska, Teodora; Andersen, Malene R; Stender, Steen; Larsen, Thomas M; Astrup, Arne; Mølgaard, Christian; Michaelsen, Kim F

2013-06-01

Dietary strategies to improve early cardiovascular markers in overweight children are needed. We investigated the effect of dietary protein and glycemic index (GI) on cardiovascular markers and metabolic syndrome (MetS) scores in 5- to 18-y-old children of overweight/obese parents from 8 European centers. Families were randomized to 1 of 5 diets consumed ad libitum: high protein (HP) or low protein (LP) combined with high GI (HGI) or low GI (LGI), or a control diet. At 6 centers, families received dietary instruction (instruction centers); at 2 centers, free foods were also provided (supermarket centers). Diet, anthropometry, blood pressure, and serum cardiovascular markers (lipid profile, glucose regulation, and inflammation) were measured in 253 children at baseline, 1 mo, and/or 6 mo. Protein intake was higher in the HP groups (19.9 ± 1.3% energy) than in the LP groups at 6 mo (16.8 ± 1.2% energy) (P = 0.001). The GI was 4.0 points lower (95% CI: 2.1, 6.1) in the LGI compared with the HGI groups (P < 0.001). In the supermarket centers, the HP and LP groups differed more in protein intake than did the groups in the instruction centers (P = 0.009), indicating better compliance. The HP diets evoked a 2.7-cm (95% CI: 0.9, 5.1) smaller waist circumference and a 0.25-mmol/L (95% CI: 0.09, 0.41) lower serum LDL cholesterol compared with the LP diets at 6 mo (P < 0.007). In a separate supermarket center analysis, the HP compared with LP diets reduced waist circumference (P = 0.004), blood pressure (P < 0.01), serum insulin (P = 0.013), and homeostasis model of assessment-insulin resistance (P = 0.016). In the instruction centers, the HP compared with the LP diets reduced LDL cholesterol (P = 0.004). No consistent effect of GI was seen and the MetS scores were not affected. In conclusion, increased protein intake improved cardiovascular markers in high-risk children, particularly in those undergoing most intensive intervention.

Plasma cortisol levels in response to a cold pressor test did not predict appetite or ad libitum test meal intake in obese women.

PubMed

Geliebter, Allan; Gibson, Charlisa D; Hernandez, Dominica B; Atalayer, Deniz; Kwon, Anne; Lee, Michelle I; Mehta, Nandini; Phair, Donna; Gluck, Marci E

2012-12-01

Heightened cortisol response to stress due to hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis may stimulate appetite and food intake. In this study, we assessed cortisol responsivity to a cold pressor test (CPT) as well as appetite ratings and subsequent test meal intake (TMI) in obese women. Following an overnight fast on two counterbalanced days, 20 obese women immersed their non-dominant hand for 2min in ice water (CPT) or warm water (WW) as a control. Plasma cortisol (ng/ml), heart rate, and blood pressure, as well as ratings of stress, pain, and appetite, were serially acquired. An ad libitum liquid meal was offered at 45min and intake measured covertly. Fasting cortisol was higher at 15min (mean peak cortisol) following the CPT compared to WW. Higher stress was reported at 2 and 15min for the CPT compared to WW. Pain, an indirect marker of the acute stress, systolic and diastolic blood pressure increased following the CPT at 2min compared to WW. Hunger decreased after the CPT at 2 and 15min, and desire to eat ratings were lower following CPT compared to WW. Subjects did not have greater test meal intake (TMI) following CPT compared to WW. There was also no significant relationship between cortisol levels following stress and TMI, indicating that cortisol did not predict subsequent intake in obese women. Copyright © 2012 Elsevier Ltd. All rights reserved.

Carcass fabrication yields of beef steers supplemented zilpaterol hydrochloride and offered ad libitum or maintenance energy intake.

PubMed

Schmitz, Angela N; Walter, Lee-Anne J; Nichols, Wade T; Hutcheson, John P; Lawrence, Ty E

2018-06-04

An experiment was conducted to evaluate the fabrication yields of carcasses from beef steers supplemented zilpaterol hydrochloride (ZH) and fed at maintenance (MA) or ad libitum (AB) intake levels. Beef steers (n = 56) from a common sire were blocked (n = 28 per block) by terminal growth implant and sorted into pairs by BW. Four pairs (n = 8) were harvested on day 0; the remaining 24 pairs (n = 48) were assigned to a dietary intake level (MA or AB) and days on feed (28 or 56 d). Within pairs of MA or AB intakes, steers harvested on day 56 were randomly assigned to supplementation of ZH (90 mg·d-1 per steer) for 20 d followed by a withdrawal period of 4 d or control (C). Steers (BW = 603.5 ± 48.1 kg) were harvested at a commercial processing facility. After a 24-h chill period, standard USDA grading procedures were used to derive a calculated yield grade and quality grade. Following grading, left carcass sides were transported to the West Texas A&M University Meat Laboratory for fabrication. Each side was fabricated into subprimals to determine individual red meat yield (RMY), trimmable fat yield (TFY), and bone yield (BY). A mixed model was used for analysis; fixed effects included treatment combinations and random effects included block and pairs. Single df contrasts tested day 0 vs. 28, day 0 vs. 56, day 28 vs. 56, MA vs. AB, and C vs. ZH. Yield of chuck eye roll differed (P = 0.05) by days on feed (0 d = 4.14, 28 d = 4.11, 56 d = 4.55%). Similarly, eye of round yield was impacted (P = 0.02) by days on feed (0 d = 1.51, 28 d = 1.37, 56 d = 1.36%). Additionally, brisket yield was altered (P < 0.01) by days on feed (0 d = 4.08, 28 d = 3.56, 56 d = 3.48%) and treatment (C = 3.34, ZH = 3.61%). For remaining subprimals, no differences (P ≥ 0.15) were detected. Furthermore, results indicated that RMY tended (P = 0.07) to differ by treatment (C = 61.35, ZH = 63.67%). Comparatively, TFY was impacted (P = 0.04) by intake (MA = 20.44, AB = 23.33%). Results from this

Adiabatic pumping solutions in global AdS

NASA Astrophysics Data System (ADS)

Carracedo, Pablo; Mas, Javier; Musso, Daniele; Serantes, Alexandre

2017-05-01

We construct a family of very simple stationary solutions to gravity coupled to a massless scalar field in global AdS. They involve a constantly rising source for the scalar field at the boundary and thereby we name them pumping solutions. We construct them numerically in D = 4. They are regular and, generically, have negative mass. We perform a study of linear and nonlinear stability and find both stable and unstable branches. In the latter case, solutions belonging to different sub-branches can either decay to black holes or to limiting cycles. This observation motivates the search for non-stationary exactly timeperiodic solutions which we actually construct. We clarify the role of pumping solutions in the context of quasistatic adiabatic quenches. In D = 3 the pumping solutions can be related to other previously known solutions, like magnetic or translationally-breaking backgrounds. From this we derive an analytic expression.

Loop corrections for Kaluza-Klein AdS amplitudes

NASA Astrophysics Data System (ADS)

Aprile, F.; Drummond, J. M.; Heslop, P.; Paul, H.

2018-05-01

Recently we conjectured the four-point amplitude of graviton multiplets in AdS5 × S5 at one loop by exploiting the operator product expansion of N = 4 super Yang-Mills theory. Here we give the first extension of those results to include Kaluza-Klein modes, obtaining the amplitude for two graviton multiplets and two states of the first KK mode. Our method again relies on resolving the large N degeneracy among a family of long double-trace operators, for which we obtain explicit formulas for the leading anomalous dimensions. Having constructed the one-loop amplitude we are able to obtain a formula for the one-loop corrections to the anomalous dimensions of all twist five double-trace operators.

On the on-shell: the action of AdS4 black holes

NASA Astrophysics Data System (ADS)

Halmagyi, Nick; Lal, Shailesh

2018-03-01

We compute the on-shell action of static, BPS black holes in AdS4 from N=2 gauged supergravity coupled to vector multiplets and show that for a certain class it is equal to minus the entropy of the black hole. Holographic renormalization is used to demonstrate that with Neumann boundary conditions on the scalar fields, the divergent and finite contributions from the asymptotic boundary vanish. The entropy arises from the extrinsic curvature on Σ g × S 1 evaluated at the horizon, where Σ g may have any genus g ≥ 0. This provides a clarification of the equivalence between the partition function of the twisted ABJM theory on Σ g × S 1 and the entropy of the dual black hole solutions. It also demonstrates that the complete entropy resides on the AdS2 × Σ g horizon geometry, implying the absence of hair for these gravity solutions.

A note on the entropy of rotating BPS AdS7 × S4 black holes

NASA Astrophysics Data System (ADS)

Hosseini, Seyed Morteza; Hristov, Kiril; Zaffaroni, Alberto

2018-05-01

In this note we show that the entropy of BPS, rotating, electrically charged AdS7 × S 4 black holes can be obtained by an extremization principle involving a particular combination of anomaly coefficients of the six-dimensional N=(2,0) theory. This result extends our previous finding for BPS, rotating AdS5 × S 5 black holes.

Effect of a High-Protein, High-Fiber Beverage Preload on Subjective Appetite Ratings and Subsequent Ad Libitum Energy Intake in Overweight Men and Women: A Randomized, Double-Blind Placebo-Controlled, Crossover Study

PubMed Central

Sharafi, Mastaneh; Alamdari, Nima; Wilson, Michael; Leidy, Heather J; Glynn, Erin L

2018-01-01

Abstract Background Dietary protein and fiber have been shown to independently improve subjective measures of appetite control. Objective The aim of this study was to determine the acute effects of a high-protein, high-fiber (HP/HFb) beverage taken as a preload compared with an isocaloric lower-protein, lower-fiber (LP/LFb) placebo beverage on subjective appetite ratings and subsequent energy intake at an ad libitum meal in healthy adults. Methods A total of 50 overweight/obese men and women [n = 25 men, 25 women; age 30 ± 2 y; body mass index (BMI) 29.6 ± 0.3 kg/m2] received a 160 kcal HP/HFb beverage containing 17 g protein and 6 g fiber on one occasion and an isocaloric LP/LFb placebo beverage containing 1 g protein and 3 g fiber on another occasion in a randomized, double-blind, crossover design. Thirty min after consumption of the beverage preload, an ad libitum pizza meal was provided to be consumed over a 30-min period. Visual analog scales (VAS) were used to assess subjective appetite ratings throughout the testing period. The Revised Restraint Scale (RRS) was used to classify participants as restrained or unrestrained eaters. Results HP/HFb led to greater reductions in postprandial desire to eat and hunger compared with LP/LFb (both, P < 0.05) but did not significantly affect postprandial fullness or prospective food consumption. Subsequent meal energy intake tended to be lower after HP/HFb compared with LP/LFb (P = 0.09). A subanalysis showed lower energy intake after HP/HFb in older participants (≥25 y) compared with LP/LFb, which was not observed in the younger participants (<25 y). Conclusions Compared with LP/LFb, a HP/HFb beverage preload reduced hunger, desire to eat, and tended to reduce subsequent food intake. Dietary restraint and age appear to influence subsequent energy intake and should be taken into account when designing nutrition interventions for weight reduction and/or maintenance. This trial was registered at clinicaltrials

Value Added in English Schools

ERIC Educational Resources Information Center

Ray, Andrew; McCormack, Tanya; Evans, Helen

2009-01-01

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

Hagedorn Temperature of AdS5/CFT4 via Integrability

NASA Astrophysics Data System (ADS)

Harmark, Troels; Wilhelm, Matthias

2018-02-01

We establish a framework for calculating the Hagedorn temperature of AdS5/CFT4 via integrability. Concretely, we derive the thermodynamic Bethe ansatz equations that yield the Hagedorn temperature of planar N =4 super Yang-Mills theory at any value of the 't Hooft coupling. We solve these equations perturbatively at weak coupling via the associated Y system, confirming the known results at tree level and one-loop order as well as deriving the previously unknown two-loop Hagedorn temperature. Finally, we comment on solving the equations at finite coupling.

Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? A systematic review.

PubMed

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

2014-01-01

The magnitude of the negative energy balance induced by exercise may be reduced due to compensatory increases in energy intake. TO ADDRESS THE QUESTION: Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? 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. 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). 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. 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. The literature is limited by the lack of adequately powered trials of sufficient duration, which have prescribed and measured exercise energy expenditure, or employed adequate assessment methods for energy and macronutrient intake. We found no consistent evidence that increased physical activity or

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

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…

Caregivers' male gender is associated with poor nutrient intake in AD families (NuAD-trial).

PubMed

Puranen, T M; Pietila, S E; Pitkala, K H; Kautiainen, H; Raivio, M; Eloniemi-Sulkava, U; Jyvakorpi, S K; Suominen, M

2014-07-01

Alzheimer patients (AD) are known to be at risk for malnutrition and their older spouses may also have nutritional problems. The aim of our study was to clarify the association of caregivers' sex on the nutrient intake of AD couples. Our study uses the baseline data of a randomized nutritional trial exploring the effectiveness of nutrition intervention among home-dwelling AD patients. The central AD register in Finland was used to recruit AD patients living with a spousal caregiver, 99 couples participated in our study. Nutritional status was assessed using the Mini-Nutritional Assessment (MNA). Nutrient intakes for both AD patients and their spouses were calculated from 3-day food diaries. The mean age of caregivers and AD spouses was 75.2 (SD 7.0) and 77.4 years (SD 5.6), respectively. According to the MNA, 40% of male and 52% of female AD spouses were at risk for malnutrition. Among male caregivers, the mean energy and protein intakes were 1605 kcal (SD 458) and 0.93 g/body kg (SD 0.30), whereas the respective figures for their female AD spouses were 1313 kcal (SD 340) and 0.86 g/body kg (SD 0.32), respectively. Among female caregivers, the mean energy and protein intakes were 1536 kcal (SD 402) and 1.00 g/body kg (SD 0.30), whereas the respective figures for their male AD spouses were 1897 kcal (SD 416) and 1.04 g/body kg (SD 0.30). The interaction between male caregiver sex and lower energy (p<0.001) and lower protein intake (p=0.0048) (adjusted for age and MMSE) was significant. Similar differences between caregiver sexes were observed with the intake of various nutrients. A gender difference exists in the ability to cope with caregiver responsibilities related to nutrition. A need exists for tailored nutritional guidance among older individuals and especially among male caregivers.

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

Exact microstate counting for dyonic black holes in AdS4

NASA Astrophysics Data System (ADS)

Benini, Francesco; Hristov, Kiril; Zaffaroni, Alberto

2017-08-01

We present a counting of microstates of a class of dyonic BPS black holes in AdS4 which precisely reproduces their Bekenstein-Hawking entropy. The counting is performed in the dual boundary description, that provides a non-perturbative definition of quantum gravity, in terms of a twisted and mass-deformed ABJM theory. We evaluate its twisted index and propose an extremization principle to extract the entropy, which reproduces the attractor mechanism in gauged supergravity.

The complexity of identifying Ryu-Takayanagi surfaces in AdS 3/CFT 2

DOE PAGES

Bao, Ning; Chatwin-Davies, A.

2016-11-07

Here, we present a constructive algorithm for the determination of Ryu-Takayanagi surfaces in AdS 3/CFT 2 which exploits previously noted connections between holographic entanglement entropy and max-flow/min-cut. We then characterize its complexity as a polynomial time algorithm.

Zooming in on AdS3/CFT2 near a BPS bound

NASA Astrophysics Data System (ADS)

Hartong, Jelle; Lei, Yang; Obers, Niels; Oling, Gerben

2018-05-01

Any ( d + 1)-dimensional CFT with a U(1) flavor symmetry, a BPS bound and an exactly marginal coupling admits a decoupling limit in which one zooms in on the spectrum close to the bound. This limit is an Inönü-Wigner contraction of so(2 , d+1)⊕ u(1) that leads to a relativistic algebra with a scaling generator but no conformal generators. In 2D CFTs, Lorentz boosts are abelian and by adding a second u(1) we find a contraction of two copies of sl(2, ℝ) ⊕ u(1) to two copies of P 2 c , the 2-dimensional centrally extended Poincaré algebra. We show that the bulk is described by a novel non-Lorentzian geometry that we refer to as pseudo-Newton-Cartan geometry. Both the Chern-Simons action on sl(2, ℝ) ⊕ u(1) and the entire phase space of asymptotically AdS3 spacetimes are well-behaved in the corresponding limit if we fix the radial component for the u(1) connection. With this choice, the resulting Newton-Cartan foliation structure is now associated not with time, but with the emerging holographic direction. Since the leaves of this foliation do not mix, the emergence of the holographic direction is much simpler than in AdS3 holography. Furthermore, we show that the asymptotic symmetry algebra of the limit theory consists of a left- and a right-moving warped Virasoro algebra.

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.

Fine Grained Chaos in AdS2 Gravity

NASA Astrophysics Data System (ADS)

Haehl, Felix M.; Rozali, Moshe

2018-03-01

Quantum chaos can be characterized by an exponential growth of the thermal out-of-time-order four-point function up to a scrambling time u^*. We discuss generalizations of this statement for certain higher-point correlation functions. For concreteness, we study the Schwarzian theory of a one-dimensional time reparametrization mode, which describes two-dimensional anti-de Sitter space (AdS2 ) gravity and the low-energy dynamics of the Sachdev-Ye-Kitaev model. We identify a particular set of 2 k -point functions, characterized as being both "maximally braided" and "k -out of time order," which exhibit exponential growth until progressively longer time scales u^*(k)˜(k -1 )u^*. We suggest an interpretation as scrambling of increasingly fine grained measures of quantum information, which correspondingly take progressively longer time to reach their thermal values.

Fine Grained Chaos in AdS_{2} Gravity.

PubMed

Haehl, Felix M; Rozali, Moshe

2018-03-23

Quantum chaos can be characterized by an exponential growth of the thermal out-of-time-order four-point function up to a scrambling time u[over ^]_{*}. We discuss generalizations of this statement for certain higher-point correlation functions. For concreteness, we study the Schwarzian theory of a one-dimensional time reparametrization mode, which describes two-dimensional anti-de Sitter space (AdS_{2}) gravity and the low-energy dynamics of the Sachdev-Ye-Kitaev model. We identify a particular set of 2k-point functions, characterized as being both "maximally braided" and "k-out of time order," which exhibit exponential growth until progressively longer time scales u[over ^]_{*}^{(k)}∼(k-1)u[over ^]_{*}. We suggest an interpretation as scrambling of increasingly fine grained measures of quantum information, which correspondingly take progressively longer time to reach their thermal values.

Thermodynamic Volume in AdS/CFT

NASA Astrophysics Data System (ADS)

Kim, Kyung Kiu; Ahn, Byoungjoon

2018-01-01

In this note, we study on extended thermodynamics of AdS black holes by varying cosmological constant. We found and discussed pressure and volume of both bulk and boundary physics through AdS/CFT correspondence. In particular, we derive the relation between thermodynamic volume and a chemical potential for M2 brane dual to four dimensional AdS space. In addition, we show that thermodynamic volume of hyperbolic black hole is related to `entanglement pressure' coming from a generalized first law of entanglement entropy.

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

Some semiclassical structure constants for AdS 4 × CP 3

NASA Astrophysics Data System (ADS)

Ahn, Changrim; Bozhilov, Plamen

2018-02-01

We compute structure constants in three-point functions of three string states in AdS 4× CP 3 in the framework of the semiclassical approach. We consider HHL correlation functions where two of the states are "heavy" string states of finite-size giant magnons carrying one or two angular momenta and the other one corresponds to such "light" states as dilaton operators with non-zero momentum, primary scalar operators, and singlet scalar operators with higher string levels.

Faster eating rates are associated with higher energy intakes during an ad libitum meal, higher BMI and greater adiposity among 4·5-year-old children: results from the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) cohort.

PubMed

Fogel, Anna; Goh, Ai Ting; Fries, Lisa R; Sadananthan, Suresh A; Velan, S Sendhil; Michael, Navin; Tint, Mya-Thway; Fortier, Marielle V; Chan, Mei Jun; Toh, Jia Ying; Chong, Yap-Seng; Tan, Kok Hian; Yap, Fabian; Shek, Lynette P; Meaney, Michael J; Broekman, Birit F P; Lee, Yung Seng; Godfrey, Keith M; Chong, Mary F F; Forde, Ciarán G

2017-04-01

Faster eating rates are associated with increased energy intake, but little is known about the relationship between children's eating rate, food intake and adiposity. We examined whether children who eat faster consume more energy and whether this is associated with higher weight status and adiposity. We hypothesised that eating rate mediates the relationship between child weight and ad libitum energy intake. Children (n 386) from the Growing Up in Singapore Towards Healthy Outcomes cohort participated in a video-recorded ad libitum lunch at 4·5 years to measure acute energy intake. Videos were coded for three eating-behaviours (bites, chews and swallows) to derive a measure of eating rate (g/min). BMI and anthropometric indices of adiposity were measured. A subset of children underwent MRI scanning (n 153) to measure abdominal subcutaneous and visceral adiposity. Children above/below the median eating rate were categorised as slower and faster eaters, and compared across body composition measures. There was a strong positive relationship between eating rate and energy intake (r 0·61, P<0·001) and a positive linear relationship between eating rate and children's BMI status. Faster eaters consumed 75 % more energy content than slower eating children (Δ548 kJ (Δ131 kcal); 95 % CI 107·6, 154·4, P<0·001), and had higher whole-body (P<0·05) and subcutaneous abdominal adiposity (Δ118·3 cc; 95 % CI 24·0, 212·7, P=0·014). Mediation analysis showed that eating rate mediates the link between child weight and energy intake during a meal (b 13·59; 95 % CI 7·48, 21·83). Children who ate faster had higher energy intake, and this was associated with increased BMI z-score and adiposity.

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…

Particle collisions near a three-dimensional warped AdS black hole

NASA Astrophysics Data System (ADS)

Bécar, Ramón; González, P. A.; Vásquez, Yerko

2018-04-01

In this paper we consider the warped AdS3 black hole solution of topologically massive gravity with a negative cosmological constant, and we study the possibility that it acts as a particle accelerator by analyzing the energy in the center of mass (CM) frame of two colliding particles in the vicinity of its horizon, which is known as the Bañnados, Silk and West (BSW) process. Mainly, we show that the critical angular momentum (L_c) of the particle decreases when the warping parameter(ν ) increases. Also, we show that despite the particle with L_c being able to exist for certain values of the conserved energy outside the horizon, it will never reach the event horizon; therefore, the black hole cannot act as a particle accelerator with arbitrarily high CM energy on the event horizon. However, such a particle could also exist inside the outer horizon, with the BSW process being possible on the inner horizon. On the other hand, for the extremal warped AdS3 black hole, the particle with L_c and energy E could exist outside the event horizon and, the CM energy blows up on the event horizon if its conserved energy fulfills the condition E2>(ν 2+3)l2/3(ν ^{2-1)}, with the BSW process being possible.

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.

ADS Bumblebee comes of age

NASA Astrophysics Data System (ADS)

Accomazzi, Alberto; Kurtz, Michael J.; Henneken, Edwin; Grant, Carolyn S.; Thompson, Donna M.; Chyla, Roman; McDonald, Steven; Shaulis, Taylor J.; Blanco-Cuaresma, Sergi; Shapurian, Golnaz; Hostetler, Timothy W.; Templeton, Matthew R.; Lockhart, Kelly E.

2018-01-01

The ADS Team has been working on a new system architecture and user interface named “ADS Bumblebee” since 2015. The new system presents many advantages over the traditional ADS interface and search engine (“ADS Classic”). A new, state of the art search engine features a number of new capabilities such as full-text search, advanced citation queries, filtering of results and scalable analytics for any search results. Its services are built on a cloud computing platform which can be easily scaled to match user demand. The Bumblebee user interface is a rich javascript application which leverages the features of the search engine and integrates a number of additional visualizations such as co-author and co-citation networks which provide a hierarchical view of research groups and research topics, respectively. Displays of paper analytics provide views of the basic article metrics (citations, reads, and age). All visualizations are interactive and provide ways to further refine search results. This new search system, which has been in beta for the past three years, has now matured to the point that it provides feature and content parity with ADS Classic, and has become the recommended way to access ADS content and services. Following a successful transition to Bumblebee, the use of ADS Classic will be discouraged starting in 2018 and phased out in 2019. You can access our new interface at https://ui.adsabs.harvard.edu

SAO/NASA ADS at SAO: User Feedback

Science.gov Websites

Sign on [SAO/NASA ADS] User Feedback ADS Home | HELP | Sitemap ADS Services Search Browse myADS Mirrors Feedback FAQ What's new Site Map Help Other NASA Centers CXC HEASARC IRSA MAST NED NSSDC PDS [NASA] NASA ads at cfa.harvard.edu

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

Ad hoc vs. Non-ad hoc Percutaneous Coronary Intervention Strategies in Patients With Stable Coronary Artery Disease.

PubMed

Toyota, Toshiaki; Morimoto, Takeshi; Shiomi, Hiroki; Ando, Kenji; Ono, Koh; Shizuta, Satoshi; Kato, Takao; Saito, Naritatsu; Furukawa, Yutaka; Nakagawa, Yoshihisa; Horie, Minoru; Kimura, Takeshi

2017-03-24

Few studies have evaluated the prevalence and clinical outcomes of ad hoc percutaneous coronary intervention (PCI), performing diagnostic coronary angiography and PCI in the same session, in stable coronary artery disease (CAD) patients.Methods and Results:From the CREDO-Kyoto PCI/CABG registry cohort-2, 6,943 patients were analyzed as having stable CAD and undergoing first PCI. Ad hoc PCI and non-ad hoc PCI were performed in 1,722 (24.8%) and 5,221 (75.1%) patients, respectively. The cumulative 5-year incidence and adjusted risk for all-cause death were not significantly different between the 2 groups (15% vs. 15%, P=0.53; hazard ratio: 1.15, 95% confidence interval: 0.98-1.35, P=0.08). Ad hoc PCI relative to non-ad hoc PCI was associated with neutral risk for myocardial infarction, any coronary revascularization, and bleeding, but was associated with a trend towards lower risk for stroke (hazard ratio: 0.78, 95% confidence interval: 0.60-1.02, P=0.06). Ad hoc PCI in stable CAD patients was associated with at least comparable 5-year clinical outcomes as with non-ad hoc PCI. Considering patients' preference and the cost-saving, the ad hoc PCI strategy might be a safe and attractive option for patients with stable CAD, although the prevalence of ad hoc PCI was low in the current study population.

Isometry group orbit quantization of spinning strings in AdS3 × S3

NASA Astrophysics Data System (ADS)

Heinze, Martin; Jorjadze, George; Megrelidze, Luka

2015-03-01

Describing the bosonic AdS3 × S3 particle and string in SU(1,1) × SU(2) group variables, we provide a Hamiltonian treatment of the isometry group orbits of solutions via analysis of the pre-symplectic form. For the particle we obtain a one-parameter family of orbits parameterized by creation-annihilation variables, which leads to the Holstein-Primakoff realization of the isometry group generators. The scheme is then applied to spinning string solutions characterized by one winding number in AdS3 and two winding numbers in S3. We find a two-parameter family of orbits, where quantization again provides the Holstein-Primakoff realization of the symmetry generators with an oscillator-type energy spectrum. Analyzing the minimal energy at strong coupling, we verify the spectrum of short strings at special values of winding numbers.

AdS5 solutions from M5-branes on Riemann surface and D6-branes sources

DOE PAGES

Bah, Ibrahima

2015-09-24

Here, we describe the gravity duals of four-dimensional N = 1 superconformal field theories obtained by wrapping M5-branes on a punctured Riemann surface. The internal geometry, normal to the AdS 5 factor, generically preserves two U(1)s, with generators (J +, J –), that are fibered over the Riemann surface. The metric is governed by a single potential that satisfies a version of the Monge-Ampère equation. The spectrum of N = 1 punctures is given by the set of supersymmetric sources of the potential that are localized on the Riemann surface and lead to regular metrics near a puncture. We usemore » this system to study a class of punctures where the geometry near the sources corresponds to M-theory description of D6-branes. These carry a natural (p, q) label associated to the circle dual to the killing vector pJ + + qJ – which shrinks near the source. In the generic case the world volume of the D6-branes is AdS 5 × S 2 and they locally preserve N = 2 supersymmetry. When p = –q, the shrinking circle is dual to a flavor U(1). The metric in this case is non-degenerate only when there are co-dimension one sources obtained by smearing M5-branes that wrap the AdS 5 factor and the circle dual the superconformal R-symmetry. The D6-branes are extended along the AdS 5 and on cups that end on the co-dimension one branes. In the special case when the shrinking circle is dual to the R-symmetry, the D6-branes are extended along the AdS 5 and wrap an auxiliary Riemann surface with an arbitrary genus. When the Riemann surface is compact with constant curvature, the system is governed by a Monge-Ampère equation.« less

Localized AdS_{5}×S^{5} Black Holes.

PubMed

Dias, Óscar J C; Santos, Jorge E; Way, Benson

2016-10-07

According to heuristic arguments, global AdS_{5}×S^{5} 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 S^{5}; at low energies, one expects "localized" black holes that appear pointlike on the S^{5}. 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.

Duality invariance of s ≥ 3/2 fermions in AdS

DOE PAGES

Deser, S.; Seminara, D.

2014-09-30

The research show that in D = 4 AdS, s ≥ 3/2 partially massless (PM) fermions retain the duality invariances of their flat space massless counterparts. They have tuned ratios m 2/M 2 ≠ 0 that turn them into sums of effectively massless unconstrained helicity ±(s, ···, 3/2) excitations, shorn of the lowest (non-dual) helicity ±1/2-rung and — more generally — of succeeding higher rung as well. Each helicity mode is separately duality invariant, like its flat space counterpart.

New Kaluza-Klein instantons and the decay of AdS vacua

DOE PAGES

Ooguri, Hirosi; Spodyneiko, Lev

2017-07-19

We construct a generalization of Witten’s Kaluza-Klein instanton, where a higher-dimensional sphere (rather than a circle as in Witten’s instanton) collapses to zero size and the geometry terminates at a bubble of nothing, in a low energy effective theory of M theory. We then use the solution to exhibit the instability of nonsupersymmetric AdS 5 vacua in M theory compactified on positive Kähler-Einstein spaces, providing further evidence for the recent conjecture that any nonsupersymmetric anti–de Sitter vacuum supported by fluxes must be unstable.

Thermodynamic Geometry of Charged AdS Black Hole Surrounded by Quintessence

NASA Astrophysics Data System (ADS)

Wei, Shao-Wen; Man, Qing-Tao; Yu, Hao

2018-02-01

In this paper, we study the thermodynamic geometry for the charged AdS black hole surrounded by quintessence. Three different kinds of the geometries are constructed, and the corresponding curvatures are obtained. It is found that there are different divergence behaviors of these curvatures, which is general thought to closely link to the phase transition of the black hole. Supported by the National Natural Science Foundation of China under Grant Nos. 11675064, 11205074, and the Fundamental Research Funds for the Central Universities under Grant No. lzujbky-2016-121

Logarithmic corrections to entropy of magnetically charged AdS4 black holes

NASA Astrophysics Data System (ADS)

Jeon, Imtak; Lal, Shailesh

2017-11-01

Logarithmic terms are quantum corrections to black hole entropy determined completely from classical data, thus providing a strong check for candidate theories of quantum gravity purely from physics in the infrared. We compute these terms in the entropy associated to the horizon of a magnetically charged extremal black hole in AdS4×S7 using the quantum entropy function and discuss the possibility of matching against recently derived microscopic expressions.

The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors.

PubMed

Claessens, M; van Baak, M A; Monsheimer, S; Saris, W H M

2009-03-01

High-protein (HP) diets are often advocated for weight reduction and weight loss maintenance. The aim was to compare the effect of low-fat, high-carbohydrate (HC) and low-fat, HP ad libitum diets on weight maintenance after weight loss induced by a very low-calorie diet, and on metabolic and cardiovascular risk factors in healthy obese subjects. Forty-eight subjects completed the study that consisted of an energy restriction period of 5-6 weeks followed by a weight maintenance period of 12 weeks. During weight maintenance subjects received maltodextrin (HC group) or protein (HP group) (casein (HPC subgroup) or whey (HPW subgroup)) supplements (2 x 25 g per day), respectively and consumed a low-fat diet. Subjects in the HP diet group showed significantly better weight maintenance after weight loss (2.3 kg difference, P=0.04) and fat mass reduction (2.2 kg difference, P=0.02) than subjects in the HC group. Triglyceride (0.6 mM difference, P=0.01) and glucagon (9.6 pg ml(-1) difference, P=0.02) concentrations increased more in the HC diet group, while glucose (0.3 mM difference, P=0.02) concentration increased more in the HP diet group. Changes in total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, insulin, HOMAir index, HbA1c, leptin and adiponectin concentrations did not differ between the diets. No differences were found between the casein- or whey-supplemented HP groups. These results show that low-fat, high-casein or whey protein weight maintenance diets are more effective for weight control than low-fat, HC diets and do not adversely affect metabolic and cardiovascular risk factors in weight-reduced moderately obese subjects without metabolic or cardiovascular complications.

Mystery cloud of AD 536

NASA Technical Reports Server (NTRS)

Stothers, R. B.

1984-01-01

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

COGNITIVELY NORMAL INDIVIDUALS WITH AD PARENTS MAY BE AT RISK FOR DEVELOPING AGING-RELATED CORTICAL THINNING PATTERNS CHARACTERISTIC OF AD

PubMed Central

Reiter, Katherine; Alpert, Kathryn I.; Cobia, Derin J.; Kwasny, Mary J.; Morris, John C.; Csernansky, John C.; Wang, Lei

2012-01-01

Children of Alzheimer's Disease (AD) patients are at heightened risk of developing AD due to genetic influences, including the apolipoprotein E4 (ApoE4) allele. In this study, we assessed the earliest cortical changes associated with AD in 71 cognitively healthy, adult children of AD patients (AD offspring) as compared with 69 with no family history of AD (non-AD offspring). Cortical thickness measures were obtained using FreeSurfer from 1.5T magnetic resonance (MR) scans. ApoE genotyping was obtained. Primary analyses examined family history and ApoeE4 effects on cortical thickness. Secondary analyses examined age effects within groups. All comparisons were adjusted using False Discovery Rate at a significance threshold of p < 0.05. There were no statistically significant differences between family history and ApoE4 groups. Within AD offspring, increasing age was related to reduced cortical thickness (atrophy) over large areas of the precuneus, superior frontal and superior temporal gyri, starting at around age 60. Further, these patterns existed within female and maternal AD offspring, but were absent in male and paternal AD offspring. Within non-AD offspring, negative correlations existed over small regions of the superior temporal, insula and lingual cortices. These results suggest that as AD offspring age, cortical atrophy is more prominent, particularly if the parent with AD is mother or if the AD offspring is female. PMID:22503937

Supersymmetric Renyi entropy in CFT 2 and AdS 3

DOE PAGES

Giveon, Amit; Kutasov, David

2016-01-01

We show that in any two dimensional conformal field theory with (2, 2) super-symmetry one can define a supersymmetric analog of the usual Renyi entropy of a spatial region A. It differs from the Renyi entropy by a universal function (which we compute) of the central charge, Renyi parameter n and the geometric parameters of A. In the limit n → 1 it coincides with the entanglement entropy. Thus, it contains the same information as the Renyi entropy but its computation only involves correlation functions of chiral and anti-chiral operators. We also show that this quantity appears naturally in stringmore » theory on AdS3.« less

Closed strings and moduli in AdS3/CFT2

NASA Astrophysics Data System (ADS)

Sax, Olof Ohlsson; Stefański, Bogdan

2018-05-01

String theory on AdS3 × S3 × T4 has 20 moduli. We investigate how the perturbative closed string spectrum changes as we move around this moduli space in both the RR and NSNS flux backgrounds. We find that, at weak string coupling, only four of the moduli affect the energies. In the RR background the only effect of these moduli is to change the radius of curvature of the background. On the other hand, in the NSNS background, the moduli introduce worldsheet interactions which enable the use of integrability methods to solve the spectral problem. Our results show that the worldsheet theory is integrable across the 20 dimensional moduli space.

Mass-deformed ABJM and black holes in AdS4

NASA Astrophysics Data System (ADS)

Bobev, Nikolay; Min, Vincent S.; Pilch, Krzysztof

2018-03-01

We find a class of new supersymmetric dyonic black holes in four-dimensional maximal gauged supergravity which are asymptotic to the SU(3) × U(1) invariant AdS4 Warner vacuum. These black holes can be embedded in eleven-dimensional supergravity where they describe the backreaction of M2-branes wrapped on a Riemann surface. The holographic dual description of these supergravity backgrounds is given by a partial topological twist on a Riemann surface of a three-dimensional N=2 SCFT that is obtained by a mass-deformation of the ABJM theory. We compute explicitly the topologically twisted index of this SCFT and show that it accounts for the entropy of the black holes.

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.

Asymptotically locally AdS and flat black holes in Horndeski theory

NASA Astrophysics Data System (ADS)

Anabalon, Andres; Cisterna, Adolfo; Oliva, Julio

2014-04-01

In this paper we construct asymptotically locally AdS and flat black holes in the presence of a scalar field whose kinetic term is constructed out from a linear combination of the metric and the Einstein tensor. The field equations as well as the energy-momentum tensor are second order in the metric and the field, therefore the theory belongs to the ones defined by Horndeski. We show that in the presence of a cosmological term in the action, it is possible to have a real scalar field in the region outside the event horizon. The solutions are characterized by a single integration constant, the scalar field vanishes at the horizon and it contributes to the effective cosmological constant at infinity. We extend these results to the topological case. The solution is disconnected from the maximally symmetric AdS background, however, within this family there exists a gravitational soliton which is everywhere regular. This soliton is therefore used as a background to define a finite Euclidean action and to obtain the thermodynamics of the black holes. For a certain region in the space of parameters, the thermodynamic analysis reveals a critical temperature at which a Hawking-Page phase transition between the black hole and the soliton occurs. We extend the solution to arbitrary dimensions greater than 4 and show that the presence of a cosmological term in the action allows one to consider the case in which the standard kinetic term for the scalar it is not present. In such a scenario, the solution reduces to an asymptotically flat black hole.

Critical behavior and microscopic structure of charged AdS black holes via an alternative phase space

NASA Astrophysics Data System (ADS)

Dehyadegari, Amin; Sheykhi, Ahmad; Montakhab, Afshin

2017-05-01

It has been argued that charged Anti-de Sitter (AdS) black holes have similar thermodynamic behavior as the Van der Waals fluid system, provided one treats the cosmological constant as a thermodynamic variable (pressure) in an extended phase space. In this paper, we disclose the deep connection between charged AdS black holes and Van der Waals fluid system from an alternative point of view. We consider the mass of an AdS black hole as a function of square of the charge Q2 instead of the standard Q, i.e. M = M (S ,Q2 , P). We first justify such a change of view mathematically and then ask if a phase transition can occur as a function of Q2 for fixed P. Therefore, we write the equation of state as Q2 =Q2 (T , Ψ) where Ψ (conjugate of Q2) is the inverse of the specific volume, Ψ = 1 / v. This allows us to complete the analogy of charged AdS black holes with Van der Waals fluid system and derive the phase transition as well as critical exponents of the system. We identify a thermodynamic instability in this new picture with real analogy to Van der Waals fluid with physically relevant Maxwell construction. We therefore study the critical behavior of isotherms in Q2- Ψ diagram and deduce all the critical exponents of the system and determine that the system exhibits a small-large black hole phase transition at the critical point (Tc , Qc2 ,Ψc). This alternative view is important as one can imagine such a change for a given single black hole i.e. acquiring charge which induces the phase transition. Finally, we disclose the microscopic properties of charged AdS black holes by using thermodynamic geometry. Interestingly, we find that scalar curvature has a gap between small and large black holes, and this gap becomes exceedingly large as one moves away from the critical point along the transition line. Therefore, we are able to attribute the sudden enlargement of the black hole to the strong repulsive nature of the internal constituents at the phase transition.

A consistent and unified picture for critical phenomena of f(R) AdS black holes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mo, Jie-Xiong; Li, Gu-Qiang; Wu, Yu-Cheng, E-mail: mojiexiong@gmail.com, E-mail: zsgqli@hotmail.com, E-mail: wuyucheng0827@163.com

A consistent and unified picture for critical phenomena of charged AdS black holes in f ( R ) gravity is drawn in this paper. Firstly, we investigate the phase transition in canonical ensemble. We derive the explicit solutions corresponding to the divergence of C {sub Q} . The two solutions merge into one when the condition Q {sub c} =√(−1/3 R {sub 0}) is satisfied. The curve of specific heat for Q < Q {sub c} has two divergent points and can be divided into three regions. Both the large radius region and the small radius region are thermodynamically stablemore » with positive specific heat while the medium radius region is unstable with negative specific heat. However, when Q > Q {sub c} , the specific heat is always positive, implying the black holes are locally stable and no phase transition will take place. Secondly, both the T − r {sub +} curve and T − S curve f ( R ) AdS black holes are investigated and they exhibit Van der Vaals like behavior as the P − v curve in the former research. Critical physical quantities are obtained and they are consistent with those derived from the specific heat analysis. We carry out numerical check of Maxwell equal area law for the cases Q =0.2 Q {sub c} , 0.4 Q {sub c} , 0.6 Q {sub c} , 0.8 Q {sub c} . The relative errors are amazingly small and can be negligible. So the Maxwell equal area law holds for T − S curve of f ( R ) black holes. Thirdly, we establish geometrothermodynamics for f ( R ) AdS black hole to examine the phase structure. It is shown that the Legendre invariant scalar curvature R would diverge exactly where the specific heat diverges. To summarize, the above three perspectives are consistent with each other, thus providing a unified picture which deepens the understanding of critical phenomena of f ( R ) AdS black holes.« less

Cognitively normal individuals with AD parents may be at risk for developing aging-related cortical thinning patterns characteristic of AD.

PubMed

Reiter, Katherine; Alpert, Kathryn I; Cobia, Derin J; Kwasny, Mary J; Morris, John C; Csernansky, John C; Wang, Lei

2012-07-02

Children of Alzheimer's disease (AD) patients are at heightened risk of developing AD due to genetic influences, including the apolipoprotein E4 (ApoE4) allele. In this study, we assessed the earliest cortical changes associated with AD in 71 cognitively healthy, adult children of AD patients (AD offspring) as compared with 69 with no family history of AD (non-AD offspring). Cortical thickness measures were obtained using FreeSurfer from 1.5T magnetic resonance (MR) scans. ApoE genotyping was obtained. Primary analyses examined family history and ApoeE4 effects on cortical thickness. Secondary analyses examined age effects within groups. All comparisons were adjusted using False Discovery Rate at a significance threshold of p<0.05. There were no statistically significant differences between family history and ApoE4 groups. Within AD offspring, increasing age was related to reduced cortical thickness (atrophy) over large areas of the precuneus, superior frontal and superior temporal gyri, starting at around age 60. Further, these patterns existed within female and maternal AD offspring, but were absent in male and paternal AD offspring. Within non-AD offspring, negative correlations existed over small regions of the superior temporal, insula and lingual cortices. These results suggest that as AD offspring age, cortical atrophy is more prominent, particularly if the parent with AD is mother or if the AD offspring is female. Copyright © 2012 Elsevier Inc. All rights reserved.

Q ‑ Φ criticality and microstructure of charged AdS black holes in f(R) gravity

NASA Astrophysics Data System (ADS)

Deng, Gao-Ming; Huang, Yong-Chang

2017-12-01

The phase transition and critical behaviors of charged AdS black holes in f(R) gravity with a conformally invariant Maxwell (CIM) source and constant curvature are further investigated. As a highlight, this research is carried out by employing new state parameters (T,Q, Φ) and contributes to deeper understanding of the thermodynamics and phase structure of black holes. Our analyses manifest that the charged f(R)-CIM AdS black hole undergoes a first-order small-large black hole phase transition, and the critical behaviors qualitatively behave like a Van der Waals liquid-vapor system. However, differing from the case in Einstein’s gravity, phase structures of the black holes in f(R) theory exhibit an interesting dependence on gravity modification parameters. Moreover, we adopt the thermodynamic geometry to probe the black hole microscopic properties. The results show that, on the one hand, both the Ruppeiner curvature and heat capacity diverge exactly at the critical point, on the other hand, the f(R)-CIM AdS black hole possesses the property as ideal Fermi gases. Of special interest, we discover a microscopic similarity between the black holes and a Van der Waals liquid-vapor system.

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.

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

What's the Value in Value-Added?

ERIC Educational Resources Information Center

Duffrin, Elizabeth

2011-01-01

A growing number of school districts are adopting "value-added" measures of teaching quality to award bonuses or even tenure. And two competitive federal grants are spurring them on. Districts using value-added data are encouraged by the results. But researchers who support value-added measures advise caution. The ratings, which use a…

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.

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.

From free fields to AdS space. II

NASA Astrophysics Data System (ADS)

Gopakumar, Rajesh

2004-07-01

We continue with the program of paper I [Phys. Rev. D 70, 025009 (2004)] to implement open-closed string duality on free gauge field theory (in the large-N limit). In this paper we consider correlators such as <∏ni=1TrΦJi(xi)>. The Schwinger parametrization of this n-point function exhibits a partial gluing up into a set of basic skeleton graphs. We argue that the moduli space of the planar skeleton graphs is exactly the same as the moduli space of genus zero Riemann surfaces with n holes. In other words, we can explicitly rewrite the n-point (planar) free-field correlator as an integral over the moduli space of a sphere with n holes. A preliminary study of the integrand also indicates compatibility with a string theory on AdS space. The details of our argument are quite insensitive to the specific form of the operators and generalize to diagrams of a higher genus as well. We take this as evidence of the field theory’s ability to reorganize itself into a string theory.

An alternative path to the boundary: The CFT as the Fourier space of AdS

NASA Astrophysics Data System (ADS)

Tolfree, Ian M.

2009-12-01

In this thesis we shed new light on the conjectured duality between an n + 1 dimensional theory of gravity in anti de Sitter space (AdS) and an n dimensional conformal field theory (CFT) by showing that the CFT can be interpreted as the Fourier space of AdS. We then make use of this to gain insight into the nature of black hole entropy. In the first part of this thesis, we give an introduction to the ideas of and review the basics of the AdS/CFT. In the next section we make use of well known integral geometry techniques to derive the Fourier transformation of a function on AdS and see it is a function with compact support on the boundary. Comparing this to the literature, we find that the Green's functions from the literature are actually the Fourier weights of the transformation and that the boundary values of fields appearing in the correspondence are the Fourier coefficients of the transformation. One is thus left to interpret the CFT as the quantized version of a classical theory in AdS and the dual operator as the Fourier coefficients. Group theoretic considerations are discussed in relation to the transformation and its potential use in constructing QCD like theories. In the last section, we then build upon this to study the BTZ black hole. Named after its authors, Banados, Teitelboim and Zanelli, the BTZ black hole is a three dimensional (two space plus one time dimension) black hole in anti de Sitter space. Following standard procedures for modifying Fourier Transformations to accommodate quotient spaces we arrive at a mapping in a black hole background consistent with known results that yields the exact micro-states of a scalar field in a black hole background. We find that the micro-states are the Fourier coefficients on the boundary, which transform under the principal series representation of SL(2, R). Using the knowledge of how to represent a bulk scalar field in the CFT, and knowing how a black hole interacts with a scalar field, we deduce the

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

Roux-En-Y Gastric Bypass and Sleeve Gastrectomy Does Not Affect Food Preferences When Assessed by an Ad libitum Buffet Meal.

PubMed

Nielsen, Mette S; Christensen, Bodil J; Ritz, Christian; Rasmussen, Simone; Hansen, Thea T; Bredie, Wender L P; le Roux, Carel W; Sjödin, Anders; Schmidt, Julie B

2017-10-01

Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) lead to a reduction in energy intake. It is uncertain whether this reduction is simply due to eating smaller portions or if surgery changes food preferences towards less energy-dense food. Previous results rely on verbal reports, which may be prone to recall bias and underestimation of especially unhealthy foods. Using an ad libitum buffet meal targeting direct behavior, we investigated if RYGB and SG surgery leads to changes in food preferences. In addition, we assessed food preferences by a picture display test to explore differences between a method relying on verbal report and a method assessing direct behavior. Forty-one subjects (BMI 45.0 ± 6.8 kg/m 2 ) completed a visit pre- and 6 months post-RYGB (n = 31) and SG (n = 10). Mean BMI decreased with 11.7 ± 0.6 kg/m 2 and total energy intake at the buffet meal with 54% (4491 ± 208 kJ vs. 2083 ± 208 kJ, P < 0.001), respectively. However, relative energy intake from the following food categories: high-fat, low-fat, sweet, savory, high-fat-savory, high-fat-sweet, low-fat-savory, and low-fat-sweet, as well as energy density did not change following surgery (all P ≥ 0.18). In contrast, the picture display test showed that food from the low-fat-savory group was chosen more often post-surgery (34 ± 8% vs. 65 ± 9%, P = 0.02). The reduction in energy intake after RYGB and SG surgery and the subsequent weight loss seems to be primarily related to a reduction in portion sizes and not by changes in food preferences towards less energy-dense foods. These results underline the necessity of investigating eating behavior by targeting direct behavior.

Quantum statistical relation for black holes in nonlinear electrodynamics coupled to Einstein-Gauss-Bonnet AdS gravity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miskovic, Olivera; Olea, Rodrigo

2011-03-15

We consider curvature-squared corrections to Einstein-Hilbert gravity action in the form of a Gauss-Bonnet term in D>4 dimensions. In this theory, we study the thermodynamics of charged static black holes with anti-de Sitter (AdS) asymptotics, and whose electric field is described by nonlinear electrodynamics. These objects have received considerable attention in recent literature on gravity/gauge dualities. It is well-known that, within the framework of anti-de Sitter/conformal field theory (AdS/CFT) correspondence, there exists a nonvanishing Casimir contribution to the internal energy of the system, manifested as the vacuum energy for global AdS spacetime in odd dimensions. Because of this reason, wemore » derive a quantum statistical relation directly from the Euclidean action and not from the integration of the first law of thermodynamics. To this end, we employ a background-independent regularization scheme which consists, in addition to the bulk action, of counterterms that depend on both extrinsic and intrinsic curvatures of the boundary (Kounterterm series). This procedure results in a consistent inclusion of the vacuum energy and chemical potential in the thermodynamic description for Einstein-Gauss-Bonnet AdS gravity regardless of the explicit form of the nonlinear electrodynamics Lagrangian.« less

Holographic reconstruction of AdS exchanges from crossing symmetry

DOE PAGES

Alday, Luis F.; Bissi, Agnese; Perlmutter, Eric

2017-08-31

Motivated by AdS/CFT, we address the following outstanding question in large N conformal field theory: given the appearance of a single-trace operator in the O x O OPE of a scalar primary O, what is its total contribution to the vacuum four-point function (OOOO) as dictated by crossing symmetry? We solve this problem in 4d conformal field theories at leading order in 1/N. Viewed holographically, this provides a field theory reconstruction of crossing-symmetric, four-point exchange amplitudes in AdS 5. Our solution takes the form of a resummation of the large spin solution to the crossing equations, supplemented by corrections atmore » finite spin, required by crossing. The method can be applied to the exchange of operators of arbitrary twist τ and spin s, although it vastly simplifies for even-integer twist, where we give explicit results. The output is the set of OPE data for the exchange of all double-trace operators [OO] n,ℓ. We find that the double-trace anomalous dimensions γ n,ℓ are negative, monotonic and convex functions of ℓ, for all n and all ℓ > s. This constitutes a holographic signature of bulk causality and classical dynamics of even-spin fields. We also find that the “derivative relation” between double-trace anomalous dimensions and OPE coefficients does not hold in general, and derive the explicit form of the deviation in several cases. Finally, we study large n limits of γ n,ℓ, relevant for the Regge and bulk-point regimes.« less

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... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... the R-value, the greater the insulating power. Ask your seller for the fact sheet on R-values.” (b) If...

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... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... the R-value, the greater the insulating power. Ask your seller for the fact sheet on R-values.” (b) If...

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... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... the R-value, the greater the insulating power. Ask your seller for the fact sheet on R-values.” (b) If...

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... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... the R-value, the greater the insulating power. Ask your seller for the fact sheet on R-values.” (b) If...

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... INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation and... the R-value, the greater the insulating power. Ask your seller for the fact sheet on R-values.” (b) If...

Aspects of warped AdS3/CFT2 correspondence

NASA Astrophysics Data System (ADS)

Chen, Bin; Zhang, Jia-Ju; Zhang, Jian-Dong; Zhong, De-Liang

2013-04-01

In this paper we apply the thermodynamics method to investigate the holographic pictures for the BTZ black hole, the spacelike and the null warped black holes in three-dimensional topologically massive gravity (TMG) and new massive gravity (NMG). Even though there are higher derivative terms in these theories, the thermodynamics method is still effective. It gives consistent results with the ones obtained by using asymptotical symmetry group (ASG) analysis. In doing the ASG analysis we develop a brute-force realization of the Barnich-Brandt-Compere formalism with Mathematica code, which also allows us to calculate the masses and the angular momenta of the black holes. In particular, we propose the warped AdS3/CFT2 correspondence in the new massive gravity, which states that quantum gravity in the warped spacetime could holographically dual to a two-dimensional CFT with {c_R}={c_L}=24 /{Gm{β^2√{{2( {21-4{β^2}} )}}}}.

DAWN: Dynamic Ad-hoc Wireless Network

DTIC Science & Technology

2016-06-19

DAWN: Dynamic Ad-hoc Wireless Network The DAWN (Dynamic Ad-hoc Wireless Networks) project is developing a general theory of complex and dynamic... wireless communication networks. To accomplish this, DAWN adopts a very different approach than those followed in the past and summarized above. DAWN... wireless communication networks. The members of DAWN investigated difference aspects of wireless mobile ad hoc networks (MANET). The views, opinions and/or

Brick walls and AdS/CFT

NASA Astrophysics Data System (ADS)

Kay, Bernard S.; Ortíz, L.

2014-05-01

We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other `fixed-background', QFT-based, approaches to holography) and in mainstream string-theoretic `Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the point of view of QFT in curved spacetime—in the framework of 't Hooft's `brick wall' model—with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein-Gordon field in the Hartle-Hawking-Israel state on dimensional Schwarzschild AdS has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the `complementarity principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to black hole entropy. Working on the assumption that similar results will hold for bulk QFT other than the Klein-Gordon field and for Schwarzschild AdS in other dimensions, and recalling the first author's proposed resolution to the Mukohyama-Israel puzzle based on his `matter-gravity entanglement hypothesis', we argue that, in Maldacena AdS/CFT, the algebra of the boundary CFT is isomorphic only to a proper subalgebra of the bulk algebra, albeit (at non-zero temperature) the (GNS) Hilbert spaces of bulk and boundary theories are still the `same'—the total bulk state being pure, while the boundary state is mixed (thermal). We also argue from the finiteness of its boundary (and hence, on our assumptions, also bulk) entropy at finite temperature, that the Rehren dual of the Maldacena boundary CFT cannot itself be a QFT and must, instead, presumably be something like a string theory.

Type IIB supergravity solution for the T-dual of the η-deformed AdS 5 × S 5 superstring

NASA Astrophysics Data System (ADS)

Hoare, B.; Tseytlin, A. A.

2015-10-01

We find an exact type IIB supergravity solution that represents a one-parameter deformation of the T-dual of the AdS 5 × S 5 background (with T-duality applied in all 6 abelian bosonic isometric directions). The non-trivial fields are the metric, dilaton and RR 5-form only. The latter has remarkably simple "undeformed" form when written in terms of a "deformation-rotated" vielbein basis. An unusual feature of this solution is that the dilaton contains a linear dependence on the isometric coordinates of the metric precluding a straightforward reversal of T-duality. If we still formally dualize back, we find exactly the metric, B-field and product of dilaton with RR field strengths as recently extracted from the η-deformed AdS 5 × S 5 superstring action in arXiv:1507.04239. We also discuss similar solutions for deformed AdS n × S n backgrounds with n = 2 , 3. In the η → i limit we demonstrate that all these backgrounds can be interpreted as special limits of gauged WZW models and are also related to (a limit of) the Pohlmeyer-reduced models of the AdS n × S n superstrings.

The Effect of Comparatively-Framed versus Similarity-Framed E-Cigarette and Snus Print Ads on Young Adults' Ad and Product Perceptions.

PubMed

Banerjee, Smita C; Greene, Kathryn; Li, Yuelin; Ostroff, Jamie S

2016-07-01

This study examined the effects of comparative-framing [C-F; ads highlighting differences between the advertised product and conventional cigarettes and/or smokeless tobacco products] versus similarity-framing (S-F; ads highlighting congruence with conventional cigarettes and/or smokeless tobacco products) in e-cigarette and snus ads on young adult smokers' and non-smokers' ad- and product-related perceptions. One thousand fifty one (1,051) young adults (18-24 years; 76% women; 50% smokers) from existing consumer panels were recruited in a within-subjects quasi-experiment. Each participant viewed 4 online advertisements, varied by tobacco product type (e-cigarette or snus) and ad framing (C-F or S-F). The dependent measures for this study were ad-related (ad perceptions, ad credibility) and product-related perceptions (absolute and comparative risk perceptions, product appeal, and product use intentions). Former and current smokers rated C-F ads as more persuasive than S-F ads, as evidenced by favorable ad perceptions and high product use intentions. Former and current smokers also rated e-cigarette ads with more favorable ad perceptions, low absolute and comparative risk perceptions, high product appeal, and high product use intentions as compared to snus ads. However, the effect sizes of the significant differences are less than.2, indicating small magnitude of difference between the study variables. Unless FDA regulates e-cig and snus advertising, there is a potential of decreasing risk perceptions and increasing use of e-cigs among young adults. Further research on implicit/explicit comparative claims in e-cigarettes and snus advertisements that encourage risk misperceptions is recommended.

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

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

2010-10-01

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 (ED(food+drink)) and ED for foods only (ED(foods)) 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 ED(food+drink). In overweight and obese children only, higher maternal restriction was associated with lower ED(food). 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.

Alteration of mTOR signaling occurs early in the progression of Alzheimer disease (AD): analysis of brain from subjects with pre-clinical AD, amnestic mild cognitive impairment and late-stage AD.

PubMed

Tramutola, Antonella; Triplett, Judy C; Di Domenico, Fabio; Niedowicz, Dana M; Murphy, Michael P; Coccia, Raffaella; Perluigi, Marzia; Butterfield, D Allan

2015-06-01

The clinical symptoms of Alzheimer disease (AD) include a gradual memory loss and subsequent dementia, and neuropathological deposition of senile plaques and neurofibrillary tangles. At the molecular level, AD subjects present overt amyloid β (Aβ) production and tau hyperphosphorylation. Aβ species have been proposed to overactivate the phosphoinositide3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) axis, which plays a central role in proteostasis. The current study investigated the status of the PI3K/Akt/mTOR pathway in post-mortem tissue from the inferior parietal lobule (IPL) at three different stages of AD: late AD, amnestic mild cognitive impairment (MCI) and pre-clinical AD (PCAD). Our findings suggest that the alteration of mTOR signaling and autophagy occurs at early stages of AD. We found a significant increase in Aβ (1-42) levels, associated with reduction in autophagy (Beclin-1 and LC-3) observed in PCAD, MCI, and AD subjects. Related to the autophagy impairment, we found a hyperactivation of PI3K/Akt/mTOR pathway in IPL of MCI and AD subjects, but not in PCAD, along with a significant decrease in phosphatase and tensin homolog. An increase in two mTOR downstream targets, p70S6K and 4EBP1, occurred in AD and MCI subjects. Both AD and MCI subjects showed increased, insulin receptor substrate 1, a candidate biomarker of brain insulin resistance, and GSK-3β, a kinase targeting tau phosphorylation. Nevertheless, tau phosphorylation was increased in the clinical groups. The results hint at a link between Aβ and the PI3K/Akt/mTOR axis and provide further insights into the relationship between AD pathology and insulin resistance. In addition, we speculate that the alteration of mTOR signaling in the IPL of AD and MCI subjects, but not in PCAD, is due to the lack of substantial increase in oxidative stress. The figure represents the three different stages of Alzheimer Disease: Preclinical Alzheimer Disease (PCAD), Mild cognitive impairment (MCI

Transition from AdS universe to DS universe in the BPP model

NASA Astrophysics Data System (ADS)

Kim, Wontae; Yoon, Myungseok

2007-04-01

It can be shown that in the BPP model the smooth phase transition from the asymptotically decelerated AdS universe to the asymptotically accelerated DS universe is possible by solving the modified semiclassical equations of motion. This transition comes from noncommutative Poisson algebra, which gives the constant curvature scalars asymptotically. The decelerated expansion of the early universe is due to the negative energy density with the negative pressure induced by quantum back reaction, and the accelerated late-time universe comes from the positive energy and the negative pressure which behave like dark energy source in recent cosmological models.

Asymptotical AdS space from nonlinear gravitational models with stabilized extra dimensions

NASA Astrophysics Data System (ADS)

Günther, U.; Moniz, P.; Zhuk, A.

2002-08-01

We consider nonlinear gravitational models with a multidimensional warped product geometry. Particular attention is payed to models with quadratic scalar curvature terms. It is shown that for certain parameter ranges, the extra dimensions are stabilized if the internal spaces have a negative constant curvature. In this case, the four-dimensional effective cosmological constant as well as the bulk cosmological constant become negative. As a consequence, the homogeneous and isotropic external space is asymptotically AdS4. The connection between the D-dimensional and the four-dimensional fundamental mass scales sets a restriction on the parameters of the considered nonlinear models.

The Effect of Comparatively-Framed versus Similarity-Framed E-Cigarette and Snus Print Ads on Young Adults’ Ad and Product Perceptions

PubMed Central

Banerjee, Smita C.; Greene, Kathryn; Li, Yuelin; Ostroff, Jamie S.

2016-01-01

Objectives This study examined the effects of comparative-framing [C-F; ads highlighting differences between the advertised product and conventional cigarettes and/or smokeless tobacco products] versus similarity-framing (S-F; ads highlighting congruence with conventional cigarettes and/or smokeless tobacco products) in e-cigarette and snus ads on young adult smokers’ and non-smokers’ ad- and product-related perceptions. Methods One thousand fifty one (1,051) young adults (18–24 years; 76% women; 50% smokers) from existing consumer panels were recruited in a within-subjects quasi-experiment. Each participant viewed 4 online advertisements, varied by tobacco product type (e-cigarette or snus) and ad framing (C-F or S-F). The dependent measures for this study were ad-related (ad perceptions, ad credibility) and product-related perceptions (absolute and comparative risk perceptions, product appeal, and product use intentions). Results Former and current smokers rated C-F ads as more persuasive than S-F ads, as evidenced by favorable ad perceptions and high product use intentions. Former and current smokers also rated e-cigarette ads with more favorable ad perceptions, low absolute and comparative risk perceptions, high product appeal, and high product use intentions as compared to snus ads. However, the effect sizes of the significant differences are less than.2, indicating small magnitude of difference between the study variables. Conclusions Unless FDA regulates e-cig and snus advertising, there is a potential of decreasing risk perceptions and increasing use of e-cigs among young adults. Further research on implicit/explicit comparative claims in e-cigarettes and snus advertisements that encourage risk misperceptions is recommended. PMID:28042597

High Energy Scattering in the AdS/CFT Correspondence

NASA Astrophysics Data System (ADS)

Penedones, Joao

2007-12-01

This work explores the celebrated AdS/CFT correspondence in the regime of high energy scattering in Anti--de Sitter (AdS) spacetime. In particular, we develop the eikonal approximation to high energy scattering in AdS and explore its consequences for the dual Conformal Field Theory (CFT). Using position space Feynman rules, we rederive the eikonal approximation for high energy scattering in flat space. Following this intuitive position space perspective, we then generalize the eikonal approximation for high energy scattering in AdS and other spacetimes. Remarkably, we are able to resum, in terms of a generalized phase shift, ladder and cross ladder Witten diagrams associated to the exchange of an AdS spin j field, to all orders in the coupling constant. By the AdS/CFT correspondence, the eikonal amplitude in AdS is related to the four point function of CFT primary operators in the regime of large 't Hooft coupling, including all terms of the 1/N expansion. We then show that the eikonal amplitude determines the behavior of the CFT four point function for small values of the cross ratios in a Lorentzian regime and that this controls its high spin and dimension conformal partial wave decomposition. These results allow us to determine the anomalous dimension of high spin and dimension double trace primary operators, by relating it to the AdS eikonal phase shift. Finally we find that, at large energies and large impact parameters in AdS, the gravitational interaction dominates all other interactions, as in flat space. Therefore, the anomalous dimension of double trace operators, associated to graviton exchange in AdS, yields a universal prediction for CFT's with AdS gravitational duals.

Feedback Form for the ADS Abstract Service

Science.gov Websites

ADS Feedback Form for the ADS Abstract Service Please use this form to report bugs or send comments to the ADS Abstract Project. Thank you for your feedback. ❉ Required field Your Name: ❉ Your E

Active and separate secretion of fiber and penton base during the early phase of Ad2 or Ad5 infection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Yuhua; Zhang, Bo; Hou, Weihong

Fiber and penton base overproduced in adenovirus (Ad) infected cells can be secreted prior to progeny release and thereby regulate progeny spread. We aimed to investigate the mechanisms of fiber and penton base secretion in Ad2- or Ad5-infected A549 cells. Our flow cytometry analyses detected abundant surface fiber molecules, but little penton base molecules at 12 h post infection. Immunogold staining combined with transmission electron microscopic analyses revealed separate, non-co-localized release of fiber and penton base in the proximity of the plasma membrane. Depolymerization of microtubule and actin cytoskeletons, and inhibition of Rock kinase and myosin II activity together demonstratedmore » cytoskeletal network-dependent fiber secretion. Inhibition of intracellular calcium [Ca{sup 2+}]{sub i} signaling caused diminished fiber secretion, which was associated with diminished progeny production. Thus, fiber and penton base are actively and separately secreted during the early stages of Ad2 or Ad5 infection, their secretion may play important role in Ad life cycle. - Highlights: •Excessive production of structural proteins is common to viral infection, which may regulate the host-virus equilibrium and the spreading of viruses. •The adenovirus (Ad) structural proteins, fiber and penton base, are respectively important for Ad binding to its receptor and subsequent internalization in host cells. In Ad infected cells, these two structural proteins are excessively produced. •The mechanisms underlying the release of fiber and penton base molecules at the early phase of Ad infection is yet poorly understood. •Our studies show that in Ad5 or Ad2 infected A549 cells, fiber and penton base molecules are actively and separately secreted. •Fiber secretion is dependent on cytoskeleton-mediated protein traffic. •Inhibition of myosin II motor and Ca{sup 2+} signaling activity significantly diminishes fiber secretion. •These findings could contribute to our

Ad Hoc Access Gateway Selection Algorithm

NASA Astrophysics Data System (ADS)

Jie, Liu

With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. For mobile nodes in Ad Hoc network to internet, internet communications in the peer nodes must be achieved through the gateway. Therefore, the key Ad Hoc Access Networks will focus on the discovery gateway, as well as gateway selection in the case of multi-gateway and handover problems between different gateways. This paper considers the mobile node and the gateway, based on the average number of hops from an average access time and the stability of routes, improved gateway selection algorithm were proposed. An improved gateway selection algorithm, which mainly considers the algorithm can improve the access time of Ad Hoc nodes and the continuity of communication between the gateways, were proposed. This can improve the quality of communication across the network.

Self-consistent geodesic equation and quantum tunneling from charged AdS black holes

NASA Astrophysics Data System (ADS)

Deng, Gao-Ming

2017-12-01

Some urgent shortcomings in previous derivations of geodesic equations are remedied in this paper. In contrast to the unnatural and awkward treatment in previous works, here we derive the geodesic equations of massive and massless particles in a unified and self- consistent manner. Furthermore, we extend to investigate the Hawking radiation via tunneling from charged black holes in the context of AdS spacetime. Of special interest, the application of the first law of black hole thermodynamics in tunneling integration manifestly simplifies the calculation.

SAO/NASA ADS at SAO: Mirror Sites

Science.gov Websites

, Garching, Germany Astronomisches Rechen-Institut, Heidelberg, Germany Institute of Astronomy of the Russian Observatory, Chinese Academy of Science, Beijing, China Inter-University Centre for Astronomy and Astrophysics Intensive Astronomy, South Africa [ADS] ADS [CfA] CfA [NASA] NASA ads at cfa.harvard.edu

Towards timelike singularity via AdS dual

NASA Astrophysics Data System (ADS)

Bhowmick, Samrat; Chatterjee, Soumyabrata

2017-07-01

It is well known that Kasner geometry with spacelike singularity can be extended to bulk AdS-like geometry, furthermore, one can study field theory on this Kasner space via its gravity dual. In this paper, we show that there exists a Kasner-like geometry with timelike singularity for which one can construct a dual gravity description. We then study various extremal surfaces including spacelike geodesics in the dual gravity description. Finally, we compute correlators of highly massive operators in the boundary field theory with a geodesic approximation.

Exploring antismoking ads: appeals, themes, and consequences.

PubMed

Beaudoin, Christopher E

2002-01-01

In this study we seek a descriptive understanding of antismoking television advertising in light of the problem cigarette consumption poses for society today. We establish relationships between ad characteristics and whether ads have a youth or adult orientation, based on a content analysis of 197 antismoking television advertisements produced between 1991 and 1999. The study finds that youth-oriented ads have youth characters, sociability, and humor as common appeals, and social and short-term consequences. In contrast, adult-oriented ads relied on fear appeals and long-term, health-related consequences.

Acute effects of different dietary polysaccharides added in milk on food intake, postprandial appetite and glycemic responses in healthy young females.

PubMed

Arshad, Muhammad Umair; Ishtiaq, Saima; Anjum, Faqir Muhammad; Saeed, Farhan; Chatha, Shahzad Ali Shahid; Imran, Ali

2016-09-01

In the present study we compared the postprandial glycemic and satiety responses of different dietary polysaccharides when added in milk (2% M.F.). The objective of this study was to evaluate different polysaccharides against postprandial glucose, appetite responses and food intake at subsequent meal. In a repeated measures design, 30 females (18-30 years) consumed 250 ml milk 2% M.F. (control), or milk with carrageenan (2.5 g), guar gum (2.5 g) and alginate (2.5 g), followed by an ad libitum pizza meal after 120 min. Alginate and guar gum addition resulted in lower caloric intake at subsequent pizza meal. The post-treatment (0-120 min) glucose and average appetite were suppressed by alginate and guar gum (p < 0.0001), with more pronounced effect of guar gum. However, alginate resulted in lower blood glucose (p < 0.0001) compared with control and carrageenan during post-treatment. Alginate and guar gum added beverages would be beneficial in short-term regulation of postprandial glycemia and satiety.

Contractions of AdS brane algebra and superGalileon Lagrangians

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamimura, Kiyoshi; Onda, Seiji

2013-06-15

We examine AdS Galileon Lagrangians using the method of nonlinear realization. By contractions (1) flat curvature limit, (2) non-relativistic brane algebra limit, and (3) (1) + (2) limits we obtain DBI, Newton-Hoock, and Galilean Galileons, respectively. We make clear how these Lagrangians appear as invariant 4-forms and/or pseudo-invariant Wess-Zumino (WZ) terms using Maurer-Cartan (MC) equations on the coset G/SO(3, 1). We show the equations of motion are written in terms of the MC forms only and explain why the inverse Higgs condition is obtained as the equation of motion for all cases. The supersymmetric extension is also examined using amore » supercoset SU(2, 2 Double-Vertical-Line 1)/(SO(3, 1) Multiplication-Sign U(1)) and five WZ forms are constructed. They are reduced to the corresponding five Galileon WZ forms in the bosonic limit and are candidates for supersymmetric Galileon action.« less

Towards Linking Anonymous Authorship in Casual Sexual Encounter Ads

PubMed Central

Fries, Jason A.; Segre, Alberto M.; Polgreen, Philip M.

2013-01-01

Objective This paper constructs an authorship-linked collection or corpus of anonymous, sex-seeking ads found on the classifieds website Craigslist. This corpus is then used to validate an authorship attribution approach based on identifying near duplicate text in ad clusters, providing insight into how often anonymous individuals post sex-seeking ads and where they meet for encounters. Introduction The increasing use of the Internet to arrange sexual encounters presents challenges to public health agencies formulating STD interventions, particularly in the context of anonymous encounters. These encounters complicate or break traditional interventions. In previous work [1], we examined a corpus of anonymous personal ads seeking sexual encounters from the classifieds website Craigslist and presented a way of linking multiple ads posted across time to a single author. The key observation of our approach is that some ads are simply reposts of older ads, often updated with only minor textual changes. Under the presumption that these ads, when not spam, originate from the same author, we can use efficient near-duplicate detection techniques to cluster ads within some threshold similarity. Linking ads in this way allows us to preserve the anonymity of authors while still extracting useful information on the frequency with which authors post ads, as well as the geographic regions in which they seek encounters. While this process detects many clusters, the lack of a true corpus of authorship-linked ads makes it difficult to validate and tune the parameters of our system. Fortunately, many ad authors provide an obfuscated telephone number in ad text (e.g., 867–5309 becomes 8sixseven5three oh nine) to bypass Craigslist filters, which prohibit including phone numbers in personal ads. By matching phone numbers of this type across all ads, we can create a corpus of ad clusters known to be written by a single author. This authorship corpus can then be used to evaluate and tune

Using the Want Ads. A Janus Survival Guide.

ERIC Educational Resources Information Center

Jew, Wing; Tandy, Carol

Originally intended for students with reading problems, this booklet may also be helpful to anyone who wants to make use of newspaper want ads. The eight teaching units discuss the following topics: (1) purposes for want ads, (2) finding want ads, (3) letting the alphabet help in reading want ads, (4) looking for a job, (5) looking for an…

Are restrictive guidelines for added sugars science based?

PubMed

Erickson, Jennifer; Slavin, Joanne

2015-12-12

Added sugar regulations and recommendations have been proposed by policy makers around the world. With no universal definition, limited access to added sugar values in food products and no analytical difference from intrinsic sugars, added sugar recommendations present a unique challenge. Average added sugar intake by American adults is approximately 13% of total energy intake, and recommendations have been made as low 5% of total energy intake. In addition to public health recommendations, the Food and Drug Administration has proposed the inclusion of added sugar data to the Nutrition and Supplemental Facts Panel. The adoption of such regulations would have implications for both consumers as well as the food industry. There are certainly advantages to including added sugar data to the Nutrition Facts Panel; however, consumer research does not consistently show the addition of this information to improve consumer knowledge. With excess calorie consumption resulting in weight gain and increased risk of obesity and obesity related co-morbidities, added sugar consumption should be minimized. However, there is currently no evidence stating that added sugar is more harmful than excess calories from any other food source. The addition of restrictive added sugar recommendations may not be the most effective intervention in the treatment and prevention of obesity and other health concerns.

Results of the ADS Communications Testing

DOT National Transportation Integrated Search

1996-01-01

Automated Dependent Surveillance or ADS is an improvement to current Vessel Traffic Service (VTS) operations and a step towards a "voiceless VTS." The two main requirements for an ADS system are an accurate position sensor on the vessel and a communi...

Authoritative parenting and issue involvement as indicators of ad recall: an empirical investigation of anti-drug ads for parents.

PubMed

Quick, Brian L; Stephenson, Michael T

2007-01-01

This investigation explores the role of authoritative parenting and issue involvement in regard to the recall of parental anti-drug ads encouraging child monitoring. In addition, the study tested whether issue involvement mediates the association between authoritative parenting and recall of parental anti-drug television ads among parents (N = 185) with adolescents in Grades 6, 7, and 8. The results indicate that (a) authoritative parenting is positively associated with favorable attitudes toward monitoring children and issue involvement regarding adolescent drug use, (b) issue involvement is associated with ad recall, (c) issue involvement mediates the relationship between authoritative parenting and ad recall, (d) ad recall is not associated with favorable attitudes toward parental monitoring, and (e) favorable attitudes regarding parental monitoring are positively associated with intentions to engage in monitoring within the next 6 months.

Microbial production of value-added nutraceuticals.

PubMed

Wang, Jian; Guleria, Sanjay; Koffas, Mattheos Ag; Yan, Yajun

2016-02-01

Nutraceuticals are important natural bioactive compounds that confer health-promoting and medical benefits to humans. Globally growing demands for value-added nutraceuticals for prevention and treatment of human diseases have rendered nutraceuticals a multi-billion dollar market. However, supply limitations and extraction difficulties from natural sources such as plants, animals or fungi, restrict the large-scale use of nutraceuticals. Metabolic engineering via microbial production platforms has been advanced as an eco-friendly alternative approach for production of value-added nutraceuticals from simple carbon sources. Microbial platforms like the most widely used Escherichia coli and Saccharomyces cerevisiae have been engineered as versatile cell factories for production of diverse and complex value-added chemicals such as phytochemicals, prebiotics, polysaccaharides and poly amino acids. This review highlights the recent progresses in biological production of value-added nutraceuticals via metabolic engineering approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Comparison of the Life Cycles of Genetically Distant Species C and Species D Human Adenoviruses Ad6 and Ad26 in Human Cells.

PubMed

Turner, Mallory A; Middha, Sumit; Hofherr, Sean E; Barry, Michael A

2015-12-01

Our understanding of adenovirus (Ad) biology is largely extrapolated from human species C Ad5. Most humans are immune to Ad5, so lower-seroprevalence viruses like human Ad6 and Ad26 are being tested as therapeutic vectors. Ad6 and Ad26 differ at the DNA level by 34%. To better understand how this might impact their biology, we examined the life cycle of the two viruses in human lung cells in vitro. Both viruses infected A549 cells with similar efficiencies, executed DNA replication with identical kinetics within 12 h, and began killing cells within 72 h. While Ad6-infected cells remained adherent until death, Ad26-infected cells detached within 12 h of infection but remained viable. Next-generation sequencing (NGS) of mRNA from infected cells demonstrated that viral transcripts constituted 1% of cellular mRNAs within 6 h and 8 to 16% within 12 h. Quantitative PCR and NGS revealed the activation of key early genes at 6 h and transition to late gene activation by 12 h by both viruses. There were marked differences in the balance of E1A and E1B activation by the two viruses and in the expression of E3 immune evasion mRNAs. Ad6 was markedly more effective at suppressing major histocompatibility complex class I (MHC I) display on the cell surface and in evading TRAIL-mediated apoptosis than was Ad26. These data demonstrate shared as well as divergent life cycles in these genetically distant human adenoviruses. An understanding of these differences expands the knowledge of alternative Ad species and may inform the selection of related Ads for therapeutic development. A burgeoning number of adenoviruses (Ads) are being harnessed as therapeutics, yet the biology of these viruses is generally extrapolated from Ad2 and Ad5. Here, we are the first to compare the transcriptional programs of two genetically distant Ads by mRNA next-generation sequencing (NGS). Species C Ad6 and Ad26 are being pursued as lower-seroprevalence Ad vectors but differ at the DNA level by 34%. Head

Sources of Added Sugars in Young Children, Adolescents, and Adults with Low and High Intakes of Added Sugars

PubMed Central

Fulgoni, Victor L.; Cowan, Alexandra E.; Gaine, P. Courtney

2018-01-01

High intake of added sugars is associated with excess energy intake and poorer diet quality. The objective of this cross-sectional study (n = 16,806) was to estimate usual intakes and the primary food sources of added sugars across the range of intakes (i.e., deciles) among U.S. children (2–8 years), adolescents and teens (9–18 years), and adults (≥19 years) using the National Health and Nutrition Examination (NHANES) data from 2009–2012. The percent energy contributed by added sugars was 14.3 ± 0.2% (2–8 years), 16.2 ± 0.2% (9–18 years), and 13.1 ± 0.2% (≥19 years), suggesting the highest intakes are among adolescents and teens. However, the primary foods/beverages that contribute to added sugars were remarkably consistent across the range of intakes, with the exception of the lowest decile, and include sweetened beverages and sweet bakery products. Interestingly across all age groups, even those in the lowest decile of added sugars exceed the 10% guidelines. Additional foods contributing to high intakes were candy and other desserts (e.g., ice cream) in children and adolescents, and coffee and teas in adults. Tailoring public health messaging to reduce intakes of these identified food groups may be of utility in designing effective strategies to reduce added sugar intake in the U.S. PMID:29342109

Sources of Added Sugars in Young Children, Adolescents, and Adults with Low and High Intakes of Added Sugars.

PubMed

Bailey, Regan L; Fulgoni, Victor L; Cowan, Alexandra E; Gaine, P Courtney

2018-01-17

High intake of added sugars is associated with excess energy intake and poorer diet quality. The objective of this cross-sectional study ( n = 16,806) was to estimate usual intakes and the primary food sources of added sugars across the range of intakes (i.e., deciles) among U.S. children (2-8 years), adolescents and teens (9-18 years), and adults (≥19 years) using the National Health and Nutrition Examination (NHANES) data from 2009-2012. The percent energy contributed by added sugars was 14.3 ± 0.2% (2-8 years), 16.2 ± 0.2% (9-18 years), and 13.1 ± 0.2% (≥19 years), suggesting the highest intakes are among adolescents and teens. However, the primary foods/beverages that contribute to added sugars were remarkably consistent across the range of intakes, with the exception of the lowest decile, and include sweetened beverages and sweet bakery products. Interestingly across all age groups, even those in the lowest decile of added sugars exceed the 10% guidelines. Additional foods contributing to high intakes were candy and other desserts (e.g., ice cream) in children and adolescents, and coffee and teas in adults. Tailoring public health messaging to reduce intakes of these identified food groups may be of utility in designing effective strategies to reduce added sugar intake in the U.S.

27 CFR 19.456 - Adding denaturants.

Code of Federal Regulations, 2010 CFR

2010-04-01

... methods of mixing denaturants and spirits if he deems such denaturation will not hinder effective... 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. 201...

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.

Intake of added sugar in Malaysia: a review.

PubMed

Amarra, Maria Sofia V; Khor, Geok Lin; Chan, Pauline

2016-01-01

The term 'added sugars' refers to sugars and syrup added to foods during processing or preparation, and sugars and syrups added at the table. Calls to limit the daily intakes of added sugars and its sources arose from evidence analysed by WHO, the American Heart Association and other organizations. The present review examined the best available evidence regarding levels of added sugar consumption among different age and sex groups in Malaysia and sources of added sugars. Information was extracted from food balance sheets, household expenditure surveys, nutrition surveys and published studies. Varying results emerged, as nationwide information on intake of sugar and foods with added sugar were obtained at different times and used different assessment methods. Data from the 2003 Malaysian Adult Nutrition Survey (MANS) using food frequency questionnaires suggested that on average, Malaysian adults consumed 30 grams of sweetened condensed milk (equivalent to 16 grams sugar) and 21 grams of table sugar per day, which together are below the WHO recommendation of 50 grams sugar for every 2000 kcal/day to reduce risk of chronic disease. Published studies suggested that, for both adults and the elderly, frequently consumed sweetened foods were beverages (tea or coffee) with sweetened condensed milk and added sugar. More accurate data should be obtained by conducting population-wide studies using biomarkers of sugar intake (e.g. 24-hour urinary sucrose and fructose excretion or serum abundance of the stable isotope 13C) to determine intake levels, and multiple 24 hour recalls to identify major food sources of added sugar.

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

AdDroid: Privilege Separation for Applications and Advertisers in Android

DTIC Science & Technology

2013-05-14

integrates these three components into the Android Open Source Project, version 2.3.3 (Ginger- bread ). 4.1 AdDroid Library API The AdDroid userspace...AdPropert ies IAB MRECT public stat ic int NO REFRESH stat ic enum AdPropert ies . Al ign BOTTOM TOP UNSET Class AdRequest public AdRequest ( ) public

Diurnal metabolic profiles after 14 d of an ad libitum high-starch, high-sucrose, or high-fat diet in normal-weight never-obese and postobese women.

PubMed

Raben, A; Holst, J J; Madsen, J; Astrup, A

2001-02-01

The influence of the amount and type of carbohydrates in the diet on risk factors for obesity, diabetes, and cardiovascular disease remains unclear. We investigated the effects of 2 low-fat diets (high-sucrose and high-starch) and a high-fat diet on glycemia, lipidemia, and hormonal responses in never-obese and postobese women. Eighteen normal-weight women (8 postobese and 10 never-obese) consumed 3 ad libitum diets (high-fat, high-starch, and high-sucrose) for 14 d each. On day 15, we measured fasting and postprandial glucose, lactate, insulin, triacylglycerol, nonesterified fatty acids (NEFA), glycerol, glucagon, glucose-dependent insulinotropic polypeptide, and glucagon-like peptide 1. The high-sucrose diet induced significantly lower total areas under the curve (AUCs) for glucose and NEFA and a significantly higher lactate AUC than did the high-fat and high-starch diets; there were no significant differences in the insulin AUCs. The triacylglycerol AUC was greater with the high-fat and high-sucrose diets than with the high-starch diet. Gastrointestinal hormone concentrations differed between diets, but not between the 2 subject groups. Comparisons between subject groups for all diets combined showed lower relative insulin resistance and lower AUCs for glucose, insulin, and triacylglycerol in the postobese group. High-starch and high-sucrose diets had no adverse effects on postprandial glycemia, insulinemia, or lipidemia compared with a high-fat diet. A sucrose-rich diet may improve glucose metabolism, but may have an adverse effect on lipidemia, compared with a starch-rich diet. Postobese women seemed to be more insulin-sensitive and more efficient at storing triacylglycerol than were never-obese women, regardless of dietary composition.

Improved Functionality and Curation Support in the ADS

NASA Astrophysics Data System (ADS)

Accomazzi, Alberto; Kurtz, Michael J.; Henneken, Edwin A.; Grant, Carolyn S.; Thompson, Donna; Chyla, Roman; Holachek, Alexandra; Sudilovsky, Vladimir; Murray, Stephen S.

2015-01-01

In this poster we describe the developments of the new ADS platform over the past year, focusing on the functionality which improves its discovery and curation capabilities.The ADS Application Programming Interface (API) is being updated to support authenticated access to the entire suite of ADS services, in addition to the search functionality itself. This allows programmatic access to resources which are specific to a user or class of users.A new interface, built directly on top of the API, now provides a more intuitive search experience and takes into account the best practices in web usability and responsive design. The interface now incorporates in-line views of graphics from the AAS Astroexplorer and the ADS All-Sky Survey image collections.The ADS Private Libraries, first introduced over 10 years ago, are now being enhanced to allow the bookmarking, tagging and annotation of records of interest. In addition, libraries can be shared with one or more ADS users, providing an easy way to collaborate in the curation of lists of papers. A library can also be explicitly made public and shared at large via the publishing of its URL.In collaboration with the AAS, the ADS plans to support the adoption of ORCID identifiers by implementing a plugin which will simplify the import of papers in ORCID via a query to the ADS API. Deeper integration between the two systems will depend on available resources and feedback from the community.

Spectral probes of the holographic Fermi ground state: Dialing between the electron star and AdS Dirac hair

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cubrovic, Mihailo; Liu Yan; Schalm, Koenraad

2011-10-15

We argue that the electron star and the anti-de Sitter (AdS) Dirac hair solution are two limits of the free charged Fermi gas in AdS. Spectral functions of holographic duals to probe fermions in the background of electron stars have a free parameter that quantifies the number of constituent fermions that make up the charge and energy density characterizing the electron star solution. The strict electron star limit takes this number to be infinite. The Dirac hair solution is the limit where this number is unity. This is evident in the behavior of the distribution of holographically dual Fermi surfaces.more » As we decrease the number of constituents in a fixed electron star background the number of Fermi surfaces also decreases. An improved holographic Fermi ground state should be a configuration that shares the qualitative properties of both limits.« less

Fast spinning strings on η deformed AdS 5 × S 5

NASA Astrophysics Data System (ADS)

Banerjee, Aritra; Bhattacharyya, Arpan; Roychowdhury, Dibakar

2018-02-01

In this paper, considering the correspondence between spin chains and string sigma models, we explore the rotating string solutions over η deformed AdS 5 × S 5 in the so-called fast spinning limit. In our analysis, we focus only on the bosonic part of the full superstring action and compute the relevant limits on both ( R × S 3) η and ( R × S 5) η models. The resulting system reveals that in the fast spinning limit, the sigma model on η deformed S 5 could be approximately thought of as the continuum limit of anisotropic SU(3) Heisenberg spin chain model. We compute the energy for a certain class of spinning strings in deformed S 5 and we show that this energy can be mapped to that of a similar spinning string in the purely imaginary β deformed background.

Research of Ad Hoc Networks Access Algorithm

NASA Astrophysics Data System (ADS)

Xiang, Ma

With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. When the ad hoc network is the access network of the internet, the gateway discovery protocol is very important to choose the most appropriate gateway to guarantee the connectivity between ad hoc network and IP based fixed networks. The paper proposes a QoS gateway discovery protocol which uses the time delay and stable route to the gateway selection conditions. And according to the gateway discovery protocol, it also proposes a fast handover scheme which can decrease the handover time and improve the handover efficiency.

q-Poincaré supersymmetry in AdS5/CFT4

NASA Astrophysics Data System (ADS)

Borsato, Riccardo; Torrielli, Alessandro

2018-03-01

We consider the exact S-matrix governing the planar spectral problem for strings on AdS5 ×S5 and N = 4 super Yang-Mills, and we show that it is invariant under a novel "boost" symmetry, which acts as a differentiation with respect to the particle momentum. This generator leads us also to reinterpret the usual centrally extended psu (2 | 2) symmetry, and to conclude that the S-matrix is invariant under a q-Poincaré supersymmetry algebra, where the deformation parameter is related to the 't Hooft coupling. We determine the two-particle action (coproduct) that turns out to be non-local, and study the property of the new symmetry under crossing transformations. We look at both the strong-coupling (large tension in the string theory) and weak-coupling (spin-chain description of the gauge theory) limits; in the former regime we calculate the cobracket utilising the universal classical r-matrix of Beisert and Spill. In the eventuality that the boost has higher partners, we also construct a quantum affine version of 2D Poincaré symmetry, by contraction of the quantum affine algebra Uq (sl2 ˆ) in Drinfeld's second realisation.

Added Sugars and Cardiovascular Disease Risk in Children

PubMed Central

Vos, Miriam B.; Kaar, Jill L.; Welsh, Jean A.; Van Horn, Linda V.; Feig, Daniel I.; Anderson, Cheryl A.M.; Patel, Mahesh J.; Munos, Jessica Cruz; Krebs, Nancy F.; Xanthakos, Stavra A.; Johnson, Rachel K.

2017-01-01

BACKGROUND Poor lifestyle behaviors are leading causes of preventable diseases globally. Added sugars contribute to a diet that is energy dense but nutrient poor and increase risk of developing obesity, cardiovascular disease, hypertension, obesity-related cancers, and dental caries. METHODS AND RESULTS For this American Heart Association scientific statement, the writing group reviewed and graded the current scientific evidence for studies examining the cardiovascular health effects of added sugars on children. The available literature was subdivided into 5 broad subareas: effects on blood pressure, lipids, insulin resistance and diabetes mellitus, nonalcoholic fatty liver disease, and obesity. CONCLUSIONS Associations between added sugars and increased cardiovascular disease risk factors among US children are present at levels far below current consumption levels. Strong evidence supports the association of added sugars with increased cardiovascular disease risk in children through increased energy intake, increased adiposity, and dyslipidemia. The committee found that it is reasonable to recommend that children consume ≤25 g (100 cal or ≈6 teaspoons) of added sugars per day and to avoid added sugars for children <2 years of age. Although added sugars most likely can be safely consumed in low amounts as part of a healthy diet, few children achieve such levels, making this an important public health target. PMID:27550974

A Comparison of Problem Behavior Profiles in Turkish Children with AD/HD and Non-AD/HD Children

ERIC Educational Resources Information Center

Ozdemir, Selda

2010-01-01

Introduction: There is an increasing number of studies describing the symptoms of ADHD among school-age children in western cultures. Yet, studies on children with ADHD living in non-western cultures are limited. Thus, the purpose of this study was to compare problem behavior profiles of Turkish children with AD/HD and non-AD/HD children. Method:…

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…

Selecting Value-Added Models for Postsecondary Institutional Assessment

ERIC Educational Resources Information Center

Steedle, Jeffrey T.

2012-01-01

Value-added scores from tests of college learning indicate how score gains compare to those expected from students of similar entering academic ability. Unfortunately, the choice of value-added model can impact results, and this makes it difficult to determine which results to trust. The research presented here demonstrates how value-added models…

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 substance...

21 CFR 509.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 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 substance...

21 CFR 509.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 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 substance...

21 CFR 509.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Added poisonous or deleterious substances. 509.6...-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 substance...

21 CFR 109.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Added poisonous or deleterious substances. 109.6...-PACKAGING MATERIAL General Provisions § 109.6 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 substance...

21 CFR 109.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Added poisonous or deleterious substances. 109.6...-PACKAGING MATERIAL General Provisions § 109.6 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 substance...

21 CFR 509.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 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 substance...

21 CFR 109.6 - Added poisonous or deleterious substances.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Added poisonous or deleterious substances. 109.6...-PACKAGING MATERIAL General Provisions § 109.6 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 substance...

AdVance male sling

PubMed Central

Chung, Amanda S. J.; Suarez, Oscar A.

2017-01-01

The AdVance sling (American Medical Systems, Minnetonka, MN, United States of America) is a synthetic transobturator sling, which is a safe and effective minimally invasive treatment for mild to moderate stress urinary incontinence (SUI) in male patients. This article provides a step-by-step description of our technique for placement of the AdVance male sling, including details and nuances gained from surgical experience, advice for avoidance of complications and discussion on management of complications and sling failures. Patient selection is very important, including exclusion and preoperative treatment of urethral stenosis and bladder dysfunction. Previous pelvic radiation is a poor prognostic factor. In brief, the steps of sling placement are: (I) mobilization of the corpus spongiosum (CS); (II) marking and mobilization of the central tendon; (III) passage of the helical trocar needles exiting at the apex of the angle between the CS and inferior pubic ramus; (IV) fixation of the broad part of the sling body to the CS at the previous mark; (V) cystoscopy during sling tensioning; (VI) placement of a Foley urethral catheter; (VII) Subcutaneous tunnelling of the sling arms back toward the midline; (VIII) wound closure. The most common early postoperative complication is urinary retention but long-term retention is extremely rare. Management of sling failures include placement of an artificial urinary sphincter, repeat AdVance sling, urethral bulking agent or ProACT device. PMID:28904900

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.

Ad35 and Ad26 Vaccine Vectors Induce Potent and Cross-Reactive Antibody and T-Cell Responses to Multiple Filovirus Species

PubMed Central

Zahn, Roland; Gillisen, Gert; Roos, Anna; Koning, Marina; van der Helm, Esmeralda; Spek, Dirk; Weijtens, Mo; Grazia Pau, Maria; Radošević, Katarina; Weverling, Gerrit Jan; Custers, Jerome; Vellinga, Jort; Schuitemaker, Hanneke; Goudsmit, Jaap; Rodríguez, Ariane

2012-01-01

Filoviruses cause sporadic but highly lethal outbreaks of hemorrhagic fever in Africa in the human population. Currently, no drug or vaccine is available for treatment or prevention. A previous study with a vaccine candidate based on the low seroprevalent adenoviruses 26 and 35 (Ad26 and Ad35) was shown to provide protection against homologous Ebola Zaire challenge in non human primates (NHP) if applied in a prime-boost regimen. Here we have aimed to expand this principle to construct and evaluate Ad26 and Ad35 vectors for development of a vaccine to provide universal filovirus protection against all highly lethal strains that have caused major outbreaks in the past. We have therefore performed a phylogenetic analysis of filovirus glycoproteins to select the glycoproteins from two Ebola species (Ebola Zaire and Ebola Sudan/Gulu,), two Marburg strains (Marburg Angola and Marburg Ravn) and added the more distant non-lethal Ebola Ivory Coast species for broadest coverage. Ad26 and Ad35 vectors expressing these five filovirus glycoproteins were evaluated to induce a potent cellular and humoral immune response in mice. All adenoviral vectors induced a humoral immune response after single vaccination in a dose dependent manner that was cross-reactive within the Ebola and Marburg lineages. In addition, both strain-specific as well as cross-reactive T cell responses could be detected. A heterologous Ad26–Ad35 prime-boost regime enhanced mainly the humoral and to a lower extend the cellular immune response against the transgene. Combination of the five selected filovirus glycoproteins in one multivalent vaccine potentially elicits protective immunity in man against all major filovirus strains that have caused lethal outbreaks in the last 20 years. PMID:23236343

First archeointensity results from Portuguese potteries (1550-1750 AD)

NASA Astrophysics Data System (ADS)

Hartmann, Gelvam A.; Trindade, Ricardo I. F.; Goguitchaichvili, Avto; Etchevarne, Carlos; Morales, Juan; Afonso, Marisa C.

2009-01-01

Geomagnetic field variations at archeomagnetic timescales can be obtained from well-dated heated structures and archeological potsherds. Here, we present the first archeointensity results obtained on Portuguese ceramics (1550 to 1750 AD) collected at Brazilian archeological sites. The results are compared to those obtained from Western Europe and currently available geomagnetic field models. Continuous thermomagnetic and IRM acquisitions curves indicate that Ti-poor titanomagnetite is responsible for the remanence in these ceramic fragments. Five fragments (24 samples) out of twelve analyzed yielded reliable intensity estimates. The row archeointensity data were corrected for TRM anisotropy and cooling rate effect. The mean dipole moments are obtained for three different age intervals: 1550±30 AD, 1600±30 AD and 1750±50 AD. Mean intensities vary from 37.9±4.2 μT to 54.8±7.6 μT in agreement with the previously reported data for 1550 AD and 1750 AD. Relatively weaker, but still highly dispersed, values were obtained for 1600 AD ceramics.

School system evaluation by value added analysis under endogeneity.

PubMed

Manzi, Jorge; San Martín, Ernesto; Van Bellegem, Sébastien

2014-01-01

Value added is a common tool in educational research on effectiveness. It is often modeled as a (prediction of a) random effect in a specific hierarchical linear model. This paper shows that this modeling strategy is not valid when endogeneity is present. Endogeneity stems, for instance, from a correlation between the random effect in the hierarchical model and some of its covariates. This paper shows that this phenomenon is far from exceptional and can even be a generic problem when the covariates contain the prior score attainments, a typical situation in value added modeling. Starting from a general, model-free definition of value added, the paper derives an explicit expression of the value added in an endogeneous hierarchical linear Gaussian model. Inference on value added is proposed using an instrumental variable approach. The impact of endogeneity on the value added and the estimated value added is calculated accurately. This is also illustrated on a large data set of individual scores of about 200,000 students in Chile.

Finite-action solutions of Yang-Mills equations on de Sitter dS4 and anti-de Sitter AdS4 spaces

NASA Astrophysics Data System (ADS)

Ivanova, Tatiana A.; Lechtenfeld, Olaf; Popov, Alexander D.

2017-11-01

We consider pure SU(2) Yang-Mills theory on four-dimensional de Sitter dS4 and anti-de Sitter AdS4 spaces and construct various solutions to the Yang-Mills equations. On de Sitter space we reduce the Yang-Mills equations via an SU(2)-equivariant ansatz to Newtonian mechanics of a particle moving in R^3 under the influence of a quartic potential. Then we describe magnetic and electric-magnetic solutions, both Abelian and non-Abelian, all having finite energy and finite action. A similar reduction on anti-de Sitter space also yields Yang-Mills solutions with finite energy and action. We propose a lower bound for the action on both backgrounds. Employing another metric on AdS4, the SU(2) Yang-Mills equations are reduced to an analytic continuation of the above particle mechanics from R^3 to R^{2,1} . We discuss analytical solutions to these equations, which produce infinite-action configurations. After a Euclidean continuation of dS4 and AdS4 we also present self-dual (instanton-type) Yang-Mills solutions on these backgrounds.

Leica ADS40 Sensor for Coastal Multispectral Imaging

NASA Technical Reports Server (NTRS)

Craig, John C.

2007-01-01

The Leica ADS40 Sensor as it is used for coastal multispectral imaging is presented. The contents include: 1) Project Area Overview; 2) Leica ADS40 Sensor; 3) Focal Plate Arrangements; 4) Trichroid Filter; 5) Gradient Correction; 6) Image Acquisition; 7) Remote Sensing and ADS40; 8) Band comparisons of Satellite and Airborne Sensors; 9) Impervious Surface Extraction; and 10) Impervious Surface Details.

AdS and dS Entropy from String Junctions or The Function of Junction Conjunctions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silverstein, Eva M

Flux compactifications of string theory exhibiting the possibility of discretely tuning the cosmological constant to small values have been constructed. The highly tuned vacua in this discretuum have curvature radii which scale as large powers of the flux quantum numbers, exponential in the number of cycles in the compactification. By the arguments of Susskind/Witten (in the AdS case) and Gibbons/Hawking (in the dS case), we expect correspondingly large entropies associated with these vacua. If they are to provide a dual description of these vacua on their Coulomb branch, branes traded for the flux need to account for this entropy atmore » the appropriate energy scale. In this note, we argue that simple string junctions and webs ending on the branes can account for this large entropy, obtaining a rough estimate for junction entropy that agrees with the existing rough estimates for the spacing of the discretuum. In particular, the brane entropy can account for the (A)dS entropy far away from string scale correspondence limits.« less

ADS Labs: Supporting Information Discovery in Science Education

NASA Astrophysics Data System (ADS)

Henneken, E. A.

2013-04-01

The SAO/NASA Astrophysics Data System (ADS) is an open access digital library portal for researchers in astronomy and physics, operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant, successfully serving the professional science community for two decades. Currently there are about 55,000 frequent users (100+ queries per year), and up to 10 million infrequent users per year. Access by the general public now accounts for about half of all ADS use, demonstrating the vast reach of the content in our databases. The visibility and use of content in the ADS can be measured by the fact that there are over 17,000 links from Wikipedia pages to ADS content, a figure comparable to the number of links that Wikipedia has to OCLC's WorldCat catalog. The ADS, through its holdings and innovative techniques available in ADS Labs, offers an environment for information discovery that is unlike any other service currently available to the astrophysics community. Literature discovery and review are important components of science education, aiding the process of preparing for a class, project, or presentation. The ADS has been recognized as a rich source of information for the science education community in astronomy, thanks to its collaborations within the astronomy community, publishers and projects like ComPADRE. One element that makes the ADS uniquely relevant for the science education community is the availability of powerful tools to explore aspects of the astronomy literature as well as the relationship between topics, people, observations and scientific papers. The other element is the extensive repository of scanned literature, a significant fraction of which consists of historical literature.

Added sugars in kids' meals from chain restaurants.

PubMed

Scourboutakos, Mary J; Semnani-Azad, Zhila; L'Abbé, Mary R

2016-06-01

To analyze the added sugars in kids' meals from Canadian chain restaurants in relation to the World Health Organization's proposed sugar recommendation (less than 5% of total daily calories should come from added sugars) and current recommendation (less than 10% of total daily calories should come from added sugars). Total sugar levels were retrieved from the websites of 10 fast-food and 7 sit-down restaurants in 2010. The added sugar levels in 3178 kids' meals from Canadian chain restaurants were calculated in 2014 (in Toronto, Canada) by subtracting all naturally occurring sugars from the total sugar level. The average amount of added sugars in restaurant kids' meals (25 ± 0.36 g) exceeded the WHO's proposed daily recommendation for sugar intake. There was a wide range of added sugar levels in kids' meals ranging from 0 g to 114 g. 50% of meals exceeded the WHO's proposed daily sugar recommendation, and 19% exceeded the WHO's current daily sugar recommendation. There is a wide range of sugar levels in kids' meals from restaurants, and many contain more than a day's worth of sugar.

Extremal Correlators in the Ads/cft Correspondence

NASA Astrophysics Data System (ADS)

D'Hoker, Eric; Freedman, Daniel Z.; Mathur, Samir D.; Matusis, Alec; Rastelli, Leonardo

The non-renormalization of the 3-point functions AdS/CFT correspondence. A two-fold puzzle appears in the extremal case, e.g. k1 = k2 + k3. First, the supergravity calculation involves analytic continuation in the ki variables to define the product of a vanishing bulk coupling and an infinite integral over AdS. Second, extremal correlators are uniquely sensitive to mixing of the single-trace operators trXk with protected multi-trace operators in the same representation of SU(4). We show that the calculation of extremal correlators from supergravity is subject to the same subtley of regularization known for 2-point functions, and we present a careful method which justifies the analytic continuation and shows that supergravity fields couple to single traces without admixture. We also study extremal n-point functions of chiral primary operators, and argue that type IIB supergravity requires that their space-time form is a product of n - 1 two-point functions (as in the free-field approximation) multiplied by a non-renormalized coefficient. This non-renormalization property of extremal n-point functions is a new prediction of the AdS/CFT correspondence. As a by-product of this work we obtain the cubic couplings tϕϕ and sϕϕ of fields in the dilaton and 5-sphere graviton towers of type IIB supergravity on AdS5 × S5.

New markers of dietary added sugar intake.

PubMed

Davy, Brenda; Jahren, Hope

2016-07-01

Added sugar consumption is associated with adverse health outcomes, including weight gain and cardio-metabolic disease, yet the reliance on self-reported methods to determine added sugar intake continues to be a significant research limitation. The purpose of this review is to summarize recent advances in the development of two potential predictive biomarkers of added sugar intake: δC and urinary sugar excretion. The results of numerous cross-sectional investigations have indicated modest associations of the δC sugar biomarker measured in a variety of sample types (e.g., fingerstick blood, serum, red blood cells, and hair) with self-reported added sugar and sugar-sweetened beverage intake, and δC values have been reported to change over time with changes in reported sugar-sweetened beverage intake. Results from large-scale trials have suggested modest associations of urinary sugar excretion with reported sugar intake, and a dose-response relation has been demonstrated between urinary sugar excretion and actual sugar intake. Valid markers of sugar intake are urgently needed to more definitively determine the health consequences of added sugar intake. Adequately powered controlled feeding studies are needed to validate and compare these two biomarkers of sugar intake, and to determine what individual characteristics and conditions impact biomarker results.

Throat quantization of the Schwarzschild-Tangherlini(-AdS) black hole

NASA Astrophysics Data System (ADS)

Maeda, Hideki

2018-01-01

By the throat quantization pioneered by Louko and Mäkelä, we derive the mass and area/entropy spectra for the Schwarzschild-Tangherlini-type asymptotically flat or AdS vacuum black hole in arbitrary dimensions. Using the WKB approximation for black holes with large mass, we show that area/entropy is equally spaced for asymptotically flat black holes, while mass is equally spaced for asymptotically AdS black holes. Exact spectra can be obtained for toroidal AdS black holes in arbitrary dimensions including the three-dimensional BTZ black hole.

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 to...

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 authorized...

Minimal unitary representation of 5d superconformal algebra F(4) and AdS 6/CFT 5 higher spin (super)-algebras

DOE PAGES

Fernando, Sudarshan; Günaydin, Murat

2014-11-28

We study the minimal unitary representation (minrep) of SO(5, 2), obtained by quantization of its geometric quasiconformal action, its deformations and supersymmetric extensions. The minrep of SO(5, 2) describes a massless conformal scalar field in five dimensions and admits a unique “deformation” which describes a massless conformal spinor. Scalar and spinor minreps of SO(5, 2) are the 5d analogs of Dirac’s singletons of SO(3, 2). We then construct the minimal unitary representation of the unique 5d supercon-formal algebra F(4) with the even subalgebra SO(5, 2) ×SU(2). The minrep of F(4) describes a massless conformal supermultiplet consisting of two scalar andmore » one spinor fields. We then extend our results to the construction of higher spin AdS 6/CFT 5 (super)-algebras. The Joseph ideal of the minrep of SO(5, 2) vanishes identically as operators and hence its enveloping algebra yields the AdS 6/CFT 5 bosonic higher spin algebra directly. The enveloping algebra of the spinor minrep defines a “deformed” higher spin algebra for which a deformed Joseph ideal vanishes identically as operators. These results are then extended to the construction of the unique higher spin AdS 6/CFT 5 superalgebra as the enveloping algebra of the minimal unitary realization of F(4) obtained by the quasiconformal methods.« less

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…

Massless spinning particle and null-string on AdS d : projective-space approach

NASA Astrophysics Data System (ADS)

Uvarov, D. V.

2018-07-01

The massless spinning particle and the tensionless string models on an AdS d background in the projective-space realization are proposed as constrained Hamiltonian systems. Various forms of particle and string Lagrangians are derived and classical mechanics is studied including the Lax-type representation of the equations of motion. After that, the transition to the quantum theory is discussed. The analysis of potential anomalies in the tensionless string model necessitates the introduction of ghosts and BRST charge. It is shown that a quantum BRST charge is nilpotent for any d if coordinate-momentum ordering for the phase-space bosonic variables, Weyl ordering for the fermions and cb () ordering for the ghosts is chosen, while conformal reparametrizations and space-time dilatations turn out to be anomalous for ordering in terms of positive and negative Fourier modes of the phase-space variables and ghosts.

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/

Phase transition and thermodynamic geometry of f (R ) AdS black holes in the grand canonical ensemble

NASA Astrophysics Data System (ADS)

Li, Gu-Qiang; Mo, Jie-Xiong

2016-06-01

The phase transition of a four-dimensional charged AdS black hole solution in the R +f (R ) gravity with constant curvature is investigated in the grand canonical ensemble, where we find novel characteristics quite different from that in the canonical ensemble. There exists no critical point for T -S curve while in former research critical point was found for both the T -S curve and T -r+ curve when the electric charge of f (R ) black holes is kept fixed. Moreover, we derive the explicit expression for the specific heat, the analog of volume expansion coefficient and isothermal compressibility coefficient when the electric potential of f (R ) AdS black hole is fixed. The specific heat CΦ encounters a divergence when 0 <Φ b . This finding also differs from the result in the canonical ensemble, where there may be two, one or no divergence points for the specific heat CQ . To examine the phase structure newly found in the grand canonical ensemble, we appeal to the well-known thermodynamic geometry tools and derive the analytic expressions for both the Weinhold scalar curvature and Ruppeiner scalar curvature. It is shown that they diverge exactly where the specific heat CΦ diverges.