WorldWideScience

Sample records for ad libitum access

  1. Ad Libitum

    Index Scriptorium Estoniae

    2001-01-01

    20. mai. Segakoor Ad Libitum laulis Niguliste Muuseum-kontserdisaalis. Dirigendid Alice Pehk ja Kaie Viigipuu. Kaastegev Tiit Kiik (orel). Esitati koorimuusikat renessansist tänapäevani ning prantsuse orelimuusikat : [täistekst

  2. Eating ad Libitum

    DEFF Research Database (Denmark)

    Hillersdal, Line

    ask what make up food stuff and eaters in the meal tests? More specifically I explore a scientific testing of changes in taste preferences before and after weight-loss surgery using an ad libitum buffet with a selection of different foods and another testing the effect of exercise on appetite also...... an eater who: ”shouldn't restrain herself”. Practices of food and eating in the test meal I suggest, will allow us to tackle reductionism by showing the complex cultural context shaping clinical intervention....

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

    Science.gov (United States)

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

    2011-06-01

    The influence of a high-protein [HP, 47% of metabolizable energy (ME)] diet on energy balance was evaluated in obese cats allowed ad libitum access to food. Energy intake, body weight, body composition, energy expenditure, and concentrations of hormones and metabolites associated with carbohydrate and lipid metabolism (glucose, insulin, free fatty acids, triglycerides and leptin) were measured in cats after consuming either a moderate protein (MP, 27% of ME) or HP diet for 4 months. Indirect respiration calorimetry showed that resting and total energy expenditure (kJ/day) adjusted for either body weight or lean body mass was increased in cats consuming the HP in relation to MP diets. However, voluntary energy intake also was increased in the HP treatment and, thus, there was no difference in body weight between animals consuming the two diets. Body composition measurements using deuterium oxide dilution showed that dietary protein content did not alter amounts of either lean body mass or fat mass. No significant differences (p > 0.05) were observed between the two treatment groups for blood glucose, free fatty acid or leptin concentrations, although there was a trend (p = 0.054) towards an increase of serum insulin concentrations in the cats eating the HP diet. This study showed that short-term ad libitum feeding of an HP diet did not reduce food intake or promote weight loss in obese cats. However, energy expenditure was increased in the HP diet group and it is possible that this effect of HP might help promote weight loss when energy intake is restricted. © 2010 Blackwell Verlag GmbH.

  4. The effect of viscosity on ad libitum food intake

    National Research Council Canada - National Science Library

    Zijlstra, N; Mars, M; Wijk, de, R.A; Westerterp-Plantenga, M; Graaf, de, C

    2008-01-01

    .... Objective: To investigate the effect of viscosity on ad libitum food intake in real-life setting and to investigate whether a difference in ad libitum intake is related to eating rate and/or eating effort. Design...

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

    Science.gov (United States)

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

    1998-03-01

    We compared fat distribution and lipoprotein lipase (LPL) activity in steers differing in adaptability to the subtropics. Steers were fed a grain diet (3.13 Mcal ME/kg DM) at limited (150 kcal ME x kg[-.75] x d[-1]; .23 kg ADG) or ad libitum levels for 140 d, then slaughtered. Sixteen British- (8 Angus, 8 Hereford; S), 16 Boran- (R), 16 Brahman- (B), and 16 Tuli- (T) cross steers from MARC III composite cows were used. Adipose tissue samples from perirenal, omental, and subcutaneous depots were analyzed for LPL activity. Carcass measurements including omental, external, and seam fat trim from 1/ 2 of the carcass were measured. Subcutaneous fat had greater (P .05) in fat distribution for steers fed at limited levels. Means for ADG, slaughter weights, carcass weights, yield grades, and carcass lipid weights for S and B fed for ad libitum intake were greater (P .05) for the other breeds with ad libitum intake. Factor analysis of fat depots for animals with ad libitum intake indicated that Bos taurus cattle differing in adaptation to heat deposited fat differently; S deposited greater (P carcass fat and T deposited greater (P < .05) proportions of internal fat. It seems that accumulation of internal fat is detrimental for ADG for Bos taurus cattle.

  6. Ad libitum and restricted day and night sleep architecture.

    Science.gov (United States)

    Korompeli, Anna St; Muurlink, Olav; Gavala, Alexandra; Myrianthefs, Pavlos; Fildissis, Georgios; Baltopoulos, Georgios

    2016-01-01

    This study represents a first controlled comparison of restricted versus unrestricted sleep in both day and night sleep categories. A repeated measures study of a homogenous group of young women without sleep disorders (n=14) found that stage 1, 2, 3 and REM sleep, as well as sleep latency were not statistically different between day ad libitum sleep (DAL) and day interrupted (DI) sleep categories, while night interrupted (NI) and ad libitum (NAL) sleep showed strikingly different architecture.

  7. Effect of alfalfa hay on growth performance, carcass characteristics, and meat quality of growing lambs with ad libitum access to total mixed rations

    Directory of Open Access Journals (Sweden)

    Ibrahim A. Alhidary

    2016-06-01

    Full Text Available ABSTRACT Forty male Naemi lambs were used to evaluate the effect of total mixed rations (TMR alone or in combination with supplementation of alfalfa hay offered at different schedules on growth, carcass characteristics, and meat quality. Lambs at the age of three months, with an average weight of 28.85±1.09 kg, were randomly selected and distributed into four different feeding systems, 10 lambs each, as follows: TMR diet (control; TMR plus 100 g alfalfa hay; TMR plus 200 g alfalfa hay every two days; and TMR plus 300 g alfalfa hay every three days. The TMR and fresh drinking water were offered ad libitum. Lambs in the treated groups (with alfalfa hay had significantly higher body weight, body weight change, dry matter intake, and feed conversion ratio compared with the control. Similarly, slaughter weight, carcass weight (hot and cold, and internal organs weight significantly increased in the treated groups, except for dressing weight percentage, which improved only in the treatment with TMR plus 300 g alfalfa hay. By contrast, mesentery fat, back fat, and body wall fat decreased in treated groups. Meat quality characteristics indicated that cooking loss and pH values did not differ between the control and treated groups; however, meat colour (lightness, yellowness, and redness and pH (1 and 24 h improved in post-slaughter treated groups. Furthermore, no difference was found in texture profile analysis (hardness, springiness, cohesiveness, and chewiness, although the shear force decreased significantly in treated groups. Addition of alfalfa hay offered at the present plan may not only improve the growth and carcass characteristics, but also enhance the meat quality of Naemi lambs. From the labour and economic point of view, TMR plus 300 g alfalfa hay every three days may be adopted while taking into account the management decision.

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

    Science.gov (United States)

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

    2014-03-01

    Soda consumption may contribute to weight gain over time. Objective data were used to determine whether soda consumption predicts weight gain or changes in glucose regulation over time. Subjects without diabetes (128 men, 75 women; mean age 34.3±8.9 years; mean body mass index 32.5±7.4; mean percentage body fat 31.6%±8.6%) self-selected their food from an ad libitum vending machine system for 3 days. Mean daily energy intake was calculated from food weight. Energy consumed from soda was recorded as were food choices that were low in fat (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, Psoda 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.

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

    NARCIS (Netherlands)

    Berkulo, M.A.R.; Bol, S.; Levels, K.; Lamberts, R.P.; Daanen, H.A.M.; Noakes, T.D.

    2016-01-01

    The aim of this study was to investigate if drinking ad-libitum can counteract potential negative effects of a hypohydrated start caused by fluid restriction during a 40-km time trial (TT) in the heat. Twelve trained males performed one 40-km cycling TT euhydrated (EU: no water during the TT) and tw

  10. Growth differences of male and female Gottingen minipigs during ad libitum feeding: a pilot study

    DEFF Research Database (Denmark)

    Bollen, P.J.A.; Madsen, L.W.; Meyer, Otto A.

    2005-01-01

    Even though minipigs have been used in biomedical research for nearly half a century now, no specific nutrient requirements are available. For that reason a series of studies into the nutrient requirements of Gottingen minipigs were carried out. Firstly, a pilot study was carried out to determine...... the ad libitum feed intake (FI) during growth, as a reference for later feed restriction studies. Four male and four female minipigs were fed two types of diet, one standard pig diet (20.6% crude protein; 11.7% crude fat; 13.5 mj/kg DM metabolizable energy) and one diet specially designed for minipigs...... backfat thickness. Relative backfat thickness ranged from 5 to 13 cm/100 kg. Females had thicker relative backfat layers than males. Remarkably, no large changes in haematology and clinical chemistry occurred in ad libitum fed Gottingen minipigs as compared to reference values, and no abnormalities other...

  11. Midbrain Response to Milkshake Correlates with Ad Libitum Milkshake Intake in the Absence of Hunger

    OpenAIRE

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

    2012-01-01

    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 predicte...

  12. Water balance and ad libitum water intake in football players during a training session

    Directory of Open Access Journals (Sweden)

    Juan Diego Hernández-Camacho

    2016-01-01

    Full Text Available Introduction: It is known that hydration plays a crucial performance in sports performance. But a great number of studies assessing hydration during football practice have shown that many players have a dehydration state prior to this sport and that most players are not able to replace water loss by sweating with ad libitum water intake. Objectives: To analyze ad libitum water consumption, water balance, thirst sensation and rate of perceived exertion on a sample of young football players during a training session. Material and Methods: A total of 57 players from three teams in the youth category voluntary participated in this study. Weight was collected at the beginning and at the end of training; thirst sensation, rate of perceived exertion and quantification of ingested water were assessed. We used descriptive statistics, correlational and ratio analysis. Results: Mean global intake of players studied was 844.74±351.95mL and an average loss of body water 1274.56±385.82mL. Average rate of dehydration of the initial weight was 0.63%. Average score of 2.81±1.32 on the scale of thirst sensation was obtained. Discussion and conclusions: Rate of loss of body water similar to previous studies is obtained. The players were not able to replace water loss by drinking liquid ad libitum, so the intake of an amount previously scheduled could become helpful.

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

    Science.gov (United States)

    Oh, Hwajung; Taylor, Adrian H

    2012-02-01

    Workplace snacking can contribute to obesity. Exercise reduces chocolate cravings but effects on chocolate consumption are unknown. This study investigated the effect of brief exercise on ad libitum consumption during breaks in a computerised task. Seventy-eight regular chocolate eaters, age: 24.90±8.15 years, BMI: 23.56±3.78 kg/m(2) abstained for 2 days. They were randomly assigned to one of four conditions, in a 2 × 2 factorial design, involving either a 15 min brisk walk or quiet rest, and then computerised Stroop tasks with low or high demanding conditions, in three 180 s blocks with a 90 s interval. Throughout, a pre-weighed bowl of chocolates was available for ad libitum eating. A two-way ANOVA revealed no interaction effect of exercise and stress on total chocolate consumption, or main effect of stress, but a main effect of exercise [F(1, 74)=7.12, pchocolate consumption was less (t(73.5)=2.69, 95% CI for difference 3.4-22.9, ES=0.61) for the exercise (15.6 g) than control (28.8 g) group. Exercise also increased affective activation, but there was no mediating effect of change in affect on chocolate consumption. A brief walk may help to reduce ad libitum snacking in regular chocolate eaters. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  14. Meal pattern analysis for effects of compound feed formulation in mid to late lactating dairy cows fed hay and compound feed both ad libitum

    NARCIS (Netherlands)

    Leen, F.; Navarro-Villa, A.; Fowers, R.; Martin-Tereso, J.; Pellikaan, W.F.

    2014-01-01

    The Kempen System is a dairy feeding system allowing ad libitum access to pelleted compound feed (CF) and hay. This system allows high DM intake (DMI) up to 30 kg DM (80% CF), but small and frequent CF meals are essential to reduce negative ruminal pH fluctuations. Little is known about feed intake

  15. Growth differences of male and female Gottingen minipigs during ad libitum feeding: a pilot study

    DEFF Research Database (Denmark)

    Bollen, P.J.A.; Madsen, L.W.; Meyer, Otto A.

    2005-01-01

    Even though minipigs have been used in biomedical research for nearly half a century now, no specific nutrient requirements are available. For that reason a series of studies into the nutrient requirements of Gottingen minipigs were carried out. Firstly, a pilot study was carried out to determine...... the ad libitum feed intake (FI) during growth, as a reference for later feed restriction studies. Four male and four female minipigs were fed two types of diet, one standard pig diet (20.6% crude protein; 11.7% crude fat; 13.5 mj/kg DM metabolizable energy) and one diet specially designed for minipigs...

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

    Science.gov (United States)

    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 (pexercise condition (pexercise condition (pExercise 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.

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

    Science.gov (United States)

    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.

  18. High-intensity intermittent exercise attenuates ad-libitum energy intake.

    Science.gov (United States)

    Sim, A Y; Wallman, K E; Fairchild, T J; Guelfi, K J

    2014-03-01

    To examine the acute effects of high-intensity intermittent exercise (HIIE) on energy intake, perceptions of appetite and appetite-related hormones in sedentary, overweight men. Seventeen overweight men (body mass index: 27.7±1.6 kg m(-2); body mass: 89.8±10.1 kg; body fat: 30.0±4.3%; VO(2peak): 39.2±4.8 ml kg(-1) min(-1)) completed four 30-min experimental conditions using a randomised counterbalanced design. CON: resting control, MC: continuous moderate-intensity exercise (60% VO(2peak)), HI: high-intensity intermittent exercise (alternating 60 s at 100% VO(2peak) and 240 s at 50% VO(2peak)), VHI: very-high-intensity intermittent exercise (alternating 15 s at 170% VO(2peak) and 60 s at 32% VO(2peak)). Participants consumed a standard caloric meal following exercise/CON and an ad-libitum meal 70 min later. Capillary blood was sampled and perceived appetite assessed at regular time intervals throughout the session. Free-living energy intake and physical activity levels for the experimental day and the day after were also assessed. Ad-libitum energy intake was lower after HI and VHI compared with CON (P=0.038 and P=0.004, respectively), and VHI was also lower than MC (P=0.028). Free-living energy intake in the subsequent 38 h remained less after VHI compared with CON and MC (P≤0.050). These observations were associated with lower active ghrelin (P≤0.050), higher blood lactate (P≤0.014) and higher blood glucose (P≤0.020) after VHI compared with all other trials. Despite higher heart rate and ratings of perceived exertion (RPE) during HI and VHI compared with MC (P≤0.004), ratings of physical activity enjoyment were similar between all the exercise trials (P=0.593). No differences were found in perceived appetite between trials. High-intensity intermittent exercise suppresses subsequent ad-libitum energy intake in overweight inactive men. This format of exercise was found to be well tolerated in an overweight population.

  19. Independent, additive effects of five dietary variables on ad libitum energy intake in a residential study.

    Science.gov (United States)

    Urban, Lorien E; McCrory, Megan A; Rasmussen, Helen; Greenberg, Andrew S; Fuss, Paul J; Saltzman, Edward; Roberts, Susan B

    2014-09-01

    To examine the relationship between dietary characteristics of self-selected foods and energy balance in a cafeteria-style dining hall. Ad libitum dietary intake from a self-selection menu was measured over two days in 151 adults (70% female, mean age 41 years, mean BMI 24.9 kg/m(2) ). The associations of dietary variables with energy balance (calculated as measured energy intake/predicted energy requirements, pER) were assessed. Measured energy intake was significantly correlated with pER (R(2) =0.83, P obese individuals. There are independent associations of dietary protein, liquid calories, energy density, dietary variety, and glycemic index with energy balance, indicating additive effects of these dietary factors on energy intake and energy balance. Intervention studies are needed to determine whether dietary prescriptions combining these dietary factors facilitate long-term prevention of weight gain. © 2014 The Obesity Society.

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

    Science.gov (United States)

    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

  1. Duration of fertility in ad libitum and feed-restricted caged broiler breeders.

    Science.gov (United States)

    Goerzen, P R; Julsrud, W L; Robinson, F E

    1996-08-01

    It has been shown in previous studies that fertility can be reduced in overweight broiler breeder (BB) flocks. In an effort to determine the effect of ad libitum feeding on the duration of fertility in BB hens, 60 52-wk-old Shaver Starbro hens were randomly assigned to one of two treatments, ad libitum feeding (F) or restricted feeding (R) to maintain breeder target weights. All hens were reared to 52 wk under conditions of feed restriction. All birds were weighed individually on a weekly basis. At the beginning of each of two 4-wk study periods (56 to 60 wk and 60 wk to 64 wk), all birds were inseminated on 2 consecutive d with 0.05 mL pooled BB semen. All eggs were weighed and placed in a forced air incubator the same day that they were laid. After 7 to 10 d of incubation, the eggs were broken out and scored macroscopically as fertile with live embryo, fertile with dead embryo (early embryonic death), or clear (assumed infertile). The duration of fertility was defined as the number of days from the day after the second insemination to the last fertile egg before two consecutive interfile eggs. Hen BW were significantly different between treatments within each of the two 4-wk studies. The mean BW of the F hens was 4,261 g in Study 1 and 4,448 g in Study 2. The BW of the R hens were 3,459 g in Study 1 and 3,565 g in Study 2. Egg production levels and average egg weight was not different between treatments in either study. In Study 1, the duration of fertility for the F hens (12.7 d) and the R hens (12.7 d) were not different. In Study 2, the durations of fertility were significantly higher (P hens (12.7 d) than in the F hens (10.0 d). These results support the theory that overweight BB have a reduced duration of fertility that may contribute to a reduced fertility in artificially inseminated and naturally mated flocks.

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

    Science.gov (United States)

    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 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.

  3. Body composition and energy expenditure predict ad-libitum food and macronutrient intake in humans.

    Science.gov (United States)

    Weise, C M; Hohenadel, M G; Krakoff, J; Votruba, S B

    2014-02-01

    Obesity is the result of chronic positive energy balance. The mechanisms underlying the regulation of energy homeostasis and food intake are not understood. Despite large increases in fat mass (FM), recent evidence indicates that fat-free mass (FFM) rather than FM is positively associated with intake in humans. In 184 humans (73 females/111 males; age 34.5±8.8 years; percentage body fat: 31.6±8.1%), we investigated the relationship of FFM index (FFMI, kg m(-2)), FM index (FMI, kg m(-2)); and 24-h energy expenditure (EE, n=127) with ad-libitum food intake using a 3-day vending machine paradigm. Mean daily calories (CAL) and macronutrient intake (PRO, CHO, FAT) were determined and used to calculate the relative caloric contribution of each (%PRO, %CHO, %FAT) and percent of caloric intake over weight maintaining energy needs (%WMENs). FFMI was positively associated with CAL (Pintake (all PFood and macronutrient intake are predicted by FFMI and to a lesser degree by FMI. FFM and FM may have opposing effects on energy homeostasis.

  4. Effects of disordered eating and obesity on weight, craving, and food intake during ad libitum smoking and abstinence.

    Science.gov (United States)

    Saules, Karen K; Pomerleau, Cynthia S; Snedecor, Sandy M; Brouwer, Rebecca Namenek; Rosenberg, Erin E M

    2004-11-01

    Although there is empirical support for the association between smoking, disordered eating, and subsequent weight gain upon smoking cessation, there have been no prospective studies to track changes in eating patterns during smoking abstinence and explore underlying biobehavioral processes. To help fill these gaps, we recruited four groups of women (N=48, 12/group) based on presence vs. absence of obesity and on low vs. high risk of severe dieting and/or binge-eating to participate in a laboratory study of eating in the context of ad libitum smoking and smoking abstinence. Participants [mean age 31.3 years; Fagerstrom Test of Nicotine Dependence (FTND) 4.3; smoking rate 18.7 cigarettes/day] completed two sessions: one after ad libitum smoking, the other after 2 days' smoking abstinence, in counterbalanced order. After a half-day's restricted eating, participants watched a video, with measured amounts of preselected preferred food available throughout. Cigarettes were available during the ad libitum smoking session. High-risk women weighed more after 2 days' abstinence than during the ad libitum smoking condition, whereas low-risk women did not differ across conditions. Nicotine craving changed significantly more in anticipation of nicotine deprivation for high-BMI women than their low-BMI counterparts. Caloric intake was marginally attenuated during abstinence for low-BMI compared with high-BMI participants (Pintake (Pfood deprivation may contribute to difficulty quitting in these women.

  5. Effect of a 3-day high-fat feeding period on carbohydrate balance and ad libitum energy intake in humans.

    Science.gov (United States)

    Galgani, J E; de Jonge, L; Most, M M; Bray, G A; Smith, S R

    2010-05-01

    A reduction in glycogen after the switch to an isoenergetic high-fat diet (HFD) might promote a compensatory increase in food intake to reestablish carbohydrate balance. We assessed the effect of an isoenergetic switch from a 49%-carbohydrate to 50%-fat diet on nutrient balance and ad libitum food intake. We hypothesized that carbohydrate balance would be inversely related to ad libitum energy intake. In 47 men and 11 women (22.6+/-0.4 years; 26.1+/-0.5 kg m(-2)), fuel balance was measured in a respiration chamber over 4 days. During the first day, an isoenergetic, high-carbohydrate diet was provided followed by a 3-day isoenergetic, HFD. At the end of this period and after 16 h of fasting, three options of foods (cookies, fruit salad and turkey sandwich) were offered ad libitum for 4 h. The relationships between post-chamber ad libitum intake and macronutrient oxidation and balance measured day-to-day and over the 4-day respiration chamber stay were studied. After switching to a HFD, 24-h respiratory quotient decreased from 0.87+/-0.02 to 0.83+/-0.02 (Plibitum energy intake. However, we detected that 4-day carbohydrate balance was a positive and independent predictor of post-chamber ad libitum energy intake (R (2)=0.10; P=0.01), whereas no significant influence of fat and protein balances was found. In response to an isoenergetic change from a high-carbohydrate to HFD, higher carbohydrate balance related to increased energy intake.

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

    Science.gov (United States)

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

    2013-01-01

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

  7. Effects of experimental negative affect manipulations on ad libitum smoking: a meta-analysis.

    Science.gov (United States)

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

    2015-05-01

    To quantify the effect of negative affect (NA), when manipulated experimentally, upon smoking as measured within laboratory paradigms. Quantitative meta-analyses tested the effects of NA versus neutral conditions on (1) latency to smoke and (2) number of puffs taken. Twelve experimental studies tested the influence of NA induction, relative to a neutral control condition (n = 1190; range = 24-235). Those providing relevant data contributed to separate random-effects meta-analyses to examine the effects of NA on two primary smoking measures: (1) latency to smoke (nine studies) and (2) number of puffs taken during ad libitum smoking (11 studies). Hedge's g was calculated for all studies through the use of post-NA cue responses relative to post-neutral cue responses. This effect size estimate is similar to Cohen's d, but corrects for small sample size bias. NA reliably decreased latency to smoke (g = -0.14; CI = -0.23 to -0.04; P = 0.007) and increased number of puffs taken (g = 0.14; CI = 0.02 to 0.25; P = 0.02). There was considerable variability across studies for both outcomes (I(2)  = 51 and 65% for latency and consumption, respectively). Potential publication bias was indicated for both outcomes, and adjusted effect sizes were smaller and no longer statistically significant. In experimental laboratory studies of smokers, negative affect appears to reduce latency to smoking and increase number of puffs taken, but this could be due to publication bias. © 2015 Society for the Study of Addiction.

  8. Use of nicotine substitute prescribed at hourly plus ab libitum intake or ad libitum for heavy smokers willing to quit: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Zellweger Jean-Pierre

    2009-06-01

    Full Text Available Abstract Objective To assess the impact of instructional guidance in the regular use of use nicotine nasal spray (NNS on the true use of NNS during the first three weeks of smoking cessation for heavy smokers who are willing to quit. Methods This randomized, open, controlled trial included 50 patients who were heavy smokers, were willing to quit, and attending an academic outpatient clinic in Western Switzerland. Patients were randomised to instruction on NNS use as "ad libitum" (administration whenever cravings appear; control group or to use NNS when craving appears and at least every hour when awake (intervention group. Intakes were monitored using an electronic device fixed in the spray unit (MDILog™ during the first three weeks of use. Self reported abstinence from smoking at six months was confirmed by expired-air carbon monoxide. Using intention-to-treat analysis, random-effect GLS regression was used to calculate the mean difference of daily doses between groups controlling for lack of independence between measures from the same individual. Results One patient was lost to follow-up. At baseline randomization, the group receiving instruction to use NNS hourly included more women, patients with previous desires to quit, and patients with more psychiatric comorbidities and less somatic complaints compared to the group instructed to use NNS with cravings (group imbalance. Both groups self-administered more than the daily recommended dosage of 8 uses. Mean daily usage was 13.6 dose/day and 11.1 dose/day for the group instructed to use NNS hourly and with cravings, respectively. Adjusting for baseline imbalance, the increased daily doses in the intervention group (hourly use remained nonsignificant compared to ad libitum use (-0.5 dose/day; CI 95% -6.2; 5.3, from day 1 to day 7; and 2.3 dose/day; CI 95% -5.4; 10.0, from day 8 to day 21. Instructing patients to use the NNS daily had no effect on smoking cessation at six months (RR = 0.69; CI

  9. Perseveration augments the effects of cognitive restraint on ad libitum food intake in adults seeking weight loss.

    Science.gov (United States)

    Graham, Alexis L; Gluck, Marci E; Votruba, Susanne B; Krakoff, Jonathan; Thearle, Marie S

    2014-11-01

    As executive function may influence eating behaviors, our aim was to determine whether measures of executive function predict ad libitum food intake in subjects seeking weight loss. 78 obese, healthy individuals (40 female/38 male; age 36 ± 10 y; BMI 37.8 ± 7.2 kg/m(2)) completed the Iowa Gambling Task to evaluate decision making, the Stroop Word Color Task to assess attention, the Wisconsin Card Sorting Task to measure perseveration, and the Three Factor Eating Questionnaire to measure disinhibition and cognitive restraint. Ad libitum energy intake over 3-days was then collected using a validated vending paradigm. When expressed as a percentage of an individual's weight maintaining energy needs (%WMEN), intake correlated positively with perseveration (r=0.24, p=0.03) and negatively with restraint (r=-0.51, pfood intake are conditional on restraint, and may contribute to extremes of dietary intake in some individuals. Published by Elsevier Ltd.

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

    Science.gov (United States)

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

    2009-01-01

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

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

    Science.gov (United States)

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

    2015-10-01

    The objectives of this study were to evaluate the effects of high-moisture corn (HMC), either whole or ground, fed separately from concentrate and straw on feeding behavior, rumen fermentation, whole tract digestibility, and nitrogen balance. Twenty-four Holstein heifers (199 ± 5.5 kg BW and 157 ± 6.9 d age) housed in individual pens were assigned to 3 treatments: 1) whole (unprocessed) HMC fed along with concentrate and barley straw, all fed separately and ad libitum (WHMC); 2) HMC ground through a 0.4-cm screen before ensiling and fed along with concentrate and barley straw, all fed separately and ad libitum (GHMC); and 3) a concentrate composed of mainly corn meal, ground through a roller mill with screen openings of 6 mm, and barley straw, both fed separately and ad libitum (Control). Concentrate, HMC, and straw were offered separately ad libitum in a free-choice situation and consumption was recorded daily and BW was recorded weekly. Apparent nutrient digestibility and N balance were determined at the beginning, middle, and end of the study. At the same time points, rumen fluid was collected through rumenocentesis to determine rumen pH and VFA concentrations. Feeding behavior was monitored throughout the study. Animals were harvested after 134 d and HCW, rumen and cecum wall lesions, and liver abscesses were recorded. Treatment did not affect total DMI, feed efficiency, ADG, final BW, and carcass weight or classification. Concentrate consumption (6.6 ± 0.35 kg/d) of Control heifers was greater ( straw resulted in performance and behavioral patterns similar to feeding only concentrate and straw.

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

    Science.gov (United States)

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

    2014-08-28

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

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

    Science.gov (United States)

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

    2017-01-01

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

  14. Exercise Does Not Protect Against Peripheral and Central Effects of a High Cholesterol Diet Given Ad Libitum in Old ApoE-/- Mice

    Directory of Open Access Journals (Sweden)

    Vanessa Di Cataldo

    2016-10-01

    Full Text Available Aim:Advanced atherosclerosis increases inflammation and stroke risk in the cerebral vasculature. Exercise is known to improve cardio-metabolic profiles when associated with a caloric restriction, but it remains debated whether it is still beneficial without the dietary control. The aim of this study was to determine both the peripheral and central effects of exercise training combined with a cholesterol-rich diet given ad libitum in old ApoE-/- mice.Methods:45-weeks old obese ApoE-/-mice fed with a high cholesterol diet ad libitum were divided into Exercise-trained (EX; running wheel free access and Sedentary (SED groups. Insulin tolerance and brain imaging were performed before and after the twelve-weeks training. Tissue insulin resistance, oxidative stress and inflammation markers in plasma, aorta and brain were then assessed.Results:In EX ApoE-/- mice, no beneficial effect of exercise was observed on weight, abdominal fat, metabolic parameters, oxidative stress, or inflammation compared to SED. Despite the regular exercise training in ApoE-/- EX mice (mean of 12.5 km/week during twelve weeks, brain inflammation imaging score was significantly associated with increased blood brain barrier (BBB leakage evaluated by imaging follow-up (r²=0.87; p=0.049 with a faster evolution compared to SED ApoE-/-mice. Conclusion:We conclude that in a context of high cardio-metabolic risk, exercise does not provide any protective effect in old ApoE-/- animals under high cholesterol diet given ad libitum. Peripheral (insulin sensitivity and oxidative/inflammatory status but also central features (BBB preservation and protection against inflammation did not show any benefits of exercise. Indeed, there was a fast induction of irreversible brain damage that was more pronounced in exercise-trained ApoE-/- mice.

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

    Science.gov (United States)

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

    2016-01-01

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

  16. Effects of additive application upon ad libitum intake, in vivo digestibility and nitrogen balance of alfalfa haylage

    Directory of Open Access Journals (Sweden)

    Mladen Knežević

    2009-09-01

    Full Text Available The research objective was to determine the effect of the additive Sill-All application on ad libitum intake, in vivo digestibility and nitrogen balance of alfalfa haylage. About 40 % alfalfa plants was ensiled at the phonological flowering stage into plastic foil-wrapped bales without or with additive (2 L t-1 plant mass. No statistically significant differences were found between alfalfa ensiled without additive and alfalfa ensiled with additive for the content of dry matter (DM (632 g and 631 g DM kg-1 fresh sample, respectively. Alfalfa ensiled without additive contained 921 g organic matter (OM kg-1 DM, which was significantly higher (P<0.001 compared to alfalfa ensiled with additive (902 g OM kg-1 DM. Alfalfa ensiled without additive contained 141 g crude proteins (CP kg-1 DM, which was significantly higher (P<0.001 compared to alfalfa ensiled with additive (139 g CP kg-1 DM. Alfalfa ensiled with additive contained significantly less acid detergent fibers (ADF (P<0.001 compared to alfalfa ensiled without additive (445 g kg-1 DM and 456 g kg-1 DM, respectively and had a lower pH value (P<0.001 (5.29 and 5.56, respectively. No statistically significant differences were found between the studied feeding treatments for ad libitum intake of fresh ration and DM ration, for the measured parameters of digestibility and N balance. It was concluded that addition of the additive to alfalfa haylage led to significant changes in chemical composition; however, changes in chemical composition had no impact on measured biological parameters (ad libitum intake, in vivo digestibility and nitrogen balance.

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

    Science.gov (United States)

    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 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.

  18. Reproducibility of an in-laboratory test meal to assess ad libitum energy intake in adolescents with obesity.

    Science.gov (United States)

    Thivel, David; Genin, Pauline Manon; Mathieu, Marie-Eve; Pereira, Bruno; Metz, Lore

    2016-10-01

    The aim of the present work was to test the reproducibility of a personalized in-laboratory ad libitum buffet meal in assessing energy and macronutrient intake in obese adolescents. Twelve 13.5 ± 1.5 years old obese adolescent girls were asked to complete three identical experimental sessions during which an ad libitum buffet meal was presented at lunch time. The buffet was personalized based on food preference questionnaires, presented usually consumed food items and excluded preferred foods. Total energy intake and the energy ingested derived from each macronutrient were assessed by investigators using the Bilnuts nutritional software. Mean body mass was 87.0 ± 13.7 kg and mean BMI was 32.2 ± 4.9 kg/m(2). Mean FM percentage was 39.1 ± 4.4% and FFM was 50.6 ± 7.7 kg. There was no significant difference between total energy intake, the percentage of intake related to fat, protein or Carbohydrates (CHO) between the three sessions. The Intraclass Correlations (ICC) observed for total energy intake was 0.99. ICC for Protein, Fat and CHO were 0.38; 0.96 and 0.81 respectively. The Bland & Altman visual analysis revealed an important agreement between meals. The proposed personalized in-laboratory ad libitum test meal produces is a reproducible methods to assess energy and macronutrients intake in obese adolescent girls. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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

  20. Meat quality of rabbits reared with two different feeding strategies: with or without fresh alfalfa ad libitum

    Directory of Open Access Journals (Sweden)

    Gustavo Capra

    2013-03-01

    Full Text Available The aim of this study was to evaluate production performance, carcass characteristics and nutritive value of meat of rabbits reared under the 2 prevailing feeding strategies in Uruguay. One week after weaning, 96 purebred V line rabbits were randomly distributed between 2 treatments: (T1 commercial pelleted food ad libitum and (T2 commercial pelleted food ad libitum plus fresh alfalfa ad libitum. Each treatment included 12 cages containing 4 individuals each (2 males and 2 females. Growth performance characteristics (live weight evolution, commercial food consumption and food/gain ratio were evaluated. The consumption of alfalfa was not measured. Rabbits were slaughtered at a live weight of 2500 g and carcass characteristics were evaluated. Samples of meat and dissectible fat were analysed to determine intramuscular fat content at muscle L. dorsi, dissectible fat and intramuscular fat composition, minerals (Zn, Fe, Mg and Na, vitamin E and purines. Sensory evaluations were conducted to assess the effect of treatments on the consumer’s perception of differences and the existence of attributes determining preferences. Differences between treatments were significant for total commercial food intake (23 356 vs. 20 930 g/cage; P<0.001 and feed conversion ratio (3.82 vs. 3.41; P<0.01 for T1 and T2 respectively. No significant differences were found in average daily gain, age at slaughter and carcass characteristics. There were no significant differences in the intramuscular fat content. The fatty acid composition of dissectible and intramuscular fat was affected the inclusion of alfalfa in the diet increasing the linolenic acid content (1.82 vs. 3.28% and 2.29 vs. 5.15% for T1 and T2 at intramuscular and dissectible fat, respectively; P<0.001, and improving the n-6/n-3 relationship (8.60 vs. 5.82 and 11.58 vs. 5.64 for T1 and T2 at intramuscular and dissectible fat, respectively; P<0.001. There were no significant differences in vitamin E

  1. Bone Composition in Male and Female Göttingen Minipigs Fed Variously Restrictedly and near ad Libitum

    DEFF Research Database (Denmark)

    Bollen, P. J. A.; Lemmens, A. G.; Beynen, A. C.;

    2006-01-01

    The current study evaluated the influence of restricted feeding at low and medium levels versus near ad libitum food intake, on the growth and bone development in male and female Göttingen minipigs aged 8 to 43 weeks fed two different types of diets. Diet 1 was a low fat, high fibre diet, whereas...... development, bone volume, and dry matter and ash content of the rib (mg) as compared to males. Also bone mineral concentrations in the femur, expressed as calcium, phosphorus and magnesium in mg/cm3, were significantly higher in females as compared to males, as was the Ca:Pi ratio. Bone density measurements...... diet 2 was a high fat, low fibre diet. A higher level of feed intake led to a significant increase in the following parameters: body weight development, bone size (length and width of rib and femur), bone volume (rib), bone (rib) dry matter and ash content (mg), as well as bone density (femur...

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

    Science.gov (United States)

    Hoch, Tobias; Pischetsrieder, Monika; Hess, Andreas

    2014-01-01

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

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

    Science.gov (United States)

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

    2012-11-01

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

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

    Directory of Open Access Journals (Sweden)

    Tobias eHoch

    2014-03-01

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

  5. Leptin receptor in the chicken ovary: potential involvement in ovarian dysfunction of ad libitum-fed broiler breeder hens

    Directory of Open Access Journals (Sweden)

    Collin Anne

    2004-10-01

    Full Text Available Abstract In hens, the ovarian follicles committed to ovulation are arranged in an ordered follicular hierarchy. In standard broiler breeders hens genetically selected for high growth rate the reproductive function is clearly dysfunctional. Feed restriction is needed during reproductive development to limit the formation of excessive numbers of ovarian yellow follicles arranged in multiple hierarchies. To determine whether leptin is involved in the nutritional and reproductive interactions controlling follicular hierarchy in hens, blood leptin levels and ovarian expression of the leptin receptor mRNA were determined during follicle maturation in three chicken lines; a slow growing broiler "Label" genotype without reproductive dysfunction, a fast growing "Standard" genotype fed ad libitum or restricted and a fast growing "Experimental" line with intermediate reproductive performance levels. Whereas expression of the leptin receptor mRNA did not change in the theca, it clearly decreased with follicular differentiation in the granulosa of slow growing hens. In fast growing standard hens fed ad libitum and presenting significant reproductive dysfunction, the decrease was disrupted and dramatic up-regulation of granulosa cell expression of the leptin receptor was observed. On the other hand, feed restriction decreased the overall level of expression of the leptin receptor mRNA and restored the decrease with follicular growth. The level of expression of the leptin receptor probably modulates the action of leptin on follicular differentiation. Since blood leptin and other metabolic factors were not affected by the genotype or by nutritional state, the factors involved in the regulation of leptin receptor gene expression remain to be determined. This study demonstrates the involvement of leptin in the nutritional control of reproduction in birds. Leptin action on the ovary probably controls follicular hierarchy through the regulation of steroidogenesis.

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

    OpenAIRE

    2015-01-01

    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 schoolbased 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....

  7. Serum lipase activity and concentration during intravenous infusions of GLP-1 and PYY3-36 and after ad libitum meal ingestion in overweight men

    DEFF Research Database (Denmark)

    Schmidt, Julie Berg; Sjödin, Anders Mikael; Stevner, Lene Susanne;

    2016-01-01

    To examine the effect on serum lipase activity and protein concentration of intravenous infusions of glucagon-like peptide-1 (GLP-1) and peptide YY (PYY3-36) and of an ad libitum meal in healthy overweight men. Twenty-five healthy, male subjects participated in this randomized, double...... the infusion and after intake of an ad libitum meal for measurement of serum lipase. Serum lipase levels measured by enzyme-linked immunosorbent assay (ELISA) following mono-infusions of GLP-1 and PYY3-36 were comparable to serum lipase levels following placebo (P = 0.054 and P = 0.873, respectively...

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

    Science.gov (United States)

    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.

  9. Both Longer Oral Sensory Exposure to and Higher Intensity of Saltiness Decrease Ad Libitum Food Intake in Healthy Normal-Weight Men

    NARCIS (Netherlands)

    Bolhuis, D.P.; Lakemond, C.M.M.; Wijk, de R.A.; Luning, P.A.; Graaf, de C.

    2011-01-01

    Orosensory exposure to sweetness has been shown to be important in satiation, whereas the effect of exposure to a salty taste on satiation is not known. The primary objective was to investigate the effect of orosensory exposure time to and intensity of saltiness in soup on ad libitum intake. The sec

  10. Performance and individual feed intake characteristics of group-housed sows fed a nonstarch polysaccharides diet ad libitum during gestation over three parities

    NARCIS (Netherlands)

    Peet-Schwering, van der C.M.C.; Kemp, B.; Plagge, J.G.; Vereijken, P.F.G.; Hartog, den L.A.; Spoolder, H.A.M.; Verstegen, M.W.A.

    2004-01-01

    The objective of this experiment was to study the effects of feeding group-housed gestating sows a diet with a high level of fermentable nonstarch polysaccharides (NSP; approximately 45% sugar beet pulp as fed) ad libitum on the development in individual feed intake characteristics and reproductive

  11. Both Longer Oral Sensory Exposure to and Higher Intensity of Saltiness Decrease Ad Libitum Food Intake in Healthy Normal-Weight Men

    NARCIS (Netherlands)

    Bolhuis, D.P.; Lakemond, C.M.M.; Wijk, de R.A.; Luning, P.A.; Graaf, de C.

    2011-01-01

    Orosensory exposure to sweetness has been shown to be important in satiation, whereas the effect of exposure to a salty taste on satiation is not known. The primary objective was to investigate the effect of orosensory exposure time to and intensity of saltiness in soup on ad libitum intake. The

  12. Effects of a high-fat meal on postprandial incretin responses, appetite scores and ad libitum energy intake in women with obesity.

    Science.gov (United States)

    Penaforte, Fernanda Rodrigues O; Japur, Camila C; Diez-Garcia, Rosa W; Chiarello, Paula G

    2017-03-30

    Considering the possible role of triglycerides (TG), glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) in the regulation of appetite, this study aimed to compare high fat meal-induced response of GIP and GLP-1, appetite scores and ad libitum energy intake in women with obesity, according to postprandial increment in triglyceridemia (∆TG).  Methods: Thirty-three no-diabetic women (BMI = 35.0 ± 3.2 kg.m-2) were divided into two groups: Group with ∆TG ≤ median were called "Low TG change -LTG" and ∆TG > median, "High TG change - HTG". Plasma concentrations of GIP, GLP-1 and appetite sensations were measured prior to, and every 30 min for 180 min after ingestion of a high-fat breakfast. An ad libitum lunch was served 3 h after the test meal. The AUC incrementalGIP were significant lower in HTG vs. LTG group (p = 0.03). The same was observed for GIP levels at 150 min (p = 0.03) and at 180 min (p libitum food intake were also similar between groups. The HTG group exhibited differences in satiety scores and lower postprandial secretion of GIP, however with no impact on ad libitum food intake in short term.

  13. Reappraise the situation but express your emotions:Impact of emotion regulation strategies on ad libitum food intake

    Directory of Open Access Journals (Sweden)

    Diana eTaut

    2012-09-01

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

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

    Directory of Open Access Journals (Sweden)

    Meyer Michael

    2012-09-01

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

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

    DEFF Research Database (Denmark)

    Hedemann, Mette Skou; Damgaard, Birthe Marie

    2012-01-01

    Metabolite profiling may elucidate changes in metabolic pathways under various physiological or nutritional conditions. In the present study two groups of female mink characterized as having a high (16 mink) or low (14 mink) residual feed intake were investigated during restrictive and ad libitum...... component analysis showed that there was no grouping of the data according to the residual feed intake. In contrast, data clearly grouped according to feeding level. Identification of the metabolites responsible for this grouping showed that the plasma level of metabolites related to mobilization of energy...... was high during restrictive feeding, e.g. betaine, carnitine, and creatine. During ad libitum feeding the plasma level of metabolites that can be characterized as biomarkers of meat intake (creatinine, carnosine, 1- and 3 methylhistidine) was high. The plasma level of lysophosphatidylcholine species...

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

    Science.gov (United States)

    2012-01-01

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

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

    DEFF Research Database (Denmark)

    Gregersen, Nikolaj Ture; Belza, Anita; Jensen, M.G.

    2013-01-01

    produced DIT, which tended to be larger than that of placebo (14 %, 59 (se 3) v. 52 (se 2) kJ/h, respectively, P = 0·08). No other spice induced thermogenic effects approaching statistical significance. Subjective measures of appetite (P>0·85), ad libitum EI (P = 0·63) and energy balance (P = 0·67) also...

  18. 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.

    Science.gov (United States)

    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 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 SSBs occurred independently of the relative amounts of fructose and glucose in the beverages. These trials were

  19. Liquid Chromatography–Mass Spectrometry Based Metabolomics Study of Cloned versus Normal Pigs Fed Either Restricted or Ad Libitum High-Energy Diets

    DEFF Research Database (Denmark)

    Christensen, Kirstine Lykke; Hedemann, Mette Skou; Jørgensen, Henry

    2012-01-01

    of the metabolome of cloned pigs compared to normal control pigs was performed to elucidate the variation and possible differences in the metabolic phenotypes during a dietary intervention. A total of 19 control pigs and 17 cloned pigs were given the same high-energy dense diet either ad libitum or in a restricted...... was however not established, suggesting a strong role for epigenetics and/or the gut microbiota to develop variation....

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

    Science.gov (United States)

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

    2010-02-01

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

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

    Science.gov (United States)

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

    2015-06-01

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

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

    Science.gov (United States)

    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 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.

  3. Ad Hoc Access Gateway Selection Algorithm

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 7.5% at baseline, the risk dropped to 5.5% (>27%) at day 7 (p 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.

  6. Age Related Assessment of Sugar and Protein Intake of Ceratitis capitata in ad libitum Conditions and Modeling Its Relation to Reproduction.

    Science.gov (United States)

    Kouloussis, Nikos A; Damos, Petros T; Ioannou, Charalambos S; Tsitsoulas, Constantinos; Papadopoulos, Nikos T; Nestel, David; Koveos, Dimitris S

    2017-01-01

    In the inquiry on the age related dietary assessment of an organism, knowledge of the distributional patterns of food intake throughout the entire life span is very important, however, age related nutritional studies often lack robust feeding quantification methods due to their limitations in obtaining short-term food-intake measurements. In this study, we developed and standardized a capillary method allowing precise life-time measurements of food consumption by individual adult medflies, Ceratitis capitata (Diptera: Tephritidae), under laboratory conditions. Protein or sugar solutions were offered via capillaries to individual adults for a 5 h interval daily and their consumption was measured, while individuals had lifetime ad libitum access to sugar or protein, respectively, in solid form. Daily egg production was also measured. The multivariate data-set (i.e., the age-dependent variations in the amount of sugar and protein ingestion and their relation to egg production) was analyzed using event history charts and 3D interpolation models. Maximum sugar intake was recorded early in adult life; afterwards, ingestion progressively dropped. On the other hand, maximum levels of protein intake were observed at mid-ages; consumption during early and late adult ages was kept at constant levels. During the first 30 days of age, type of diet and sex significantly contributed to the observed difference in diet intake while number of laid eggs varied independently. Male and female adult longevity was differentially affected by diet: protein ingestion extended the lifespan, especially, of males. Smooth surface models revealed a significant relationship between the age dependent dietary intake and reproduction. Both sugar and protein related egg-production have a bell-shaped relationship, and the association between protein and egg-production is better described by a 3D Lorenzian function. Additionally, the proposed 3D interpolation models produced good estimates of egg

  7. Age Related Assessment of Sugar and Protein Intake of Ceratitis capitata in ad libitum Conditions and Modeling Its Relation to Reproduction

    Directory of Open Access Journals (Sweden)

    Nikos A. Kouloussis

    2017-05-01

    Full Text Available In the inquiry on the age related dietary assessment of an organism, knowledge of the distributional patterns of food intake throughout the entire life span is very important, however, age related nutritional studies often lack robust feeding quantification methods due to their limitations in obtaining short-term food-intake measurements. In this study, we developed and standardized a capillary method allowing precise life-time measurements of food consumption by individual adult medflies, Ceratitis capitata (Diptera: Tephritidae, under laboratory conditions. Protein or sugar solutions were offered via capillaries to individual adults for a 5 h interval daily and their consumption was measured, while individuals had lifetime ad libitum access to sugar or protein, respectively, in solid form. Daily egg production was also measured. The multivariate data-set (i.e., the age-dependent variations in the amount of sugar and protein ingestion and their relation to egg production was analyzed using event history charts and 3D interpolation models. Maximum sugar intake was recorded early in adult life; afterwards, ingestion progressively dropped. On the other hand, maximum levels of protein intake were observed at mid-ages; consumption during early and late adult ages was kept at constant levels. During the first 30 days of age, type of diet and sex significantly contributed to the observed difference in diet intake while number of laid eggs varied independently. Male and female adult longevity was differentially affected by diet: protein ingestion extended the lifespan, especially, of males. Smooth surface models revealed a significant relationship between the age dependent dietary intake and reproduction. Both sugar and protein related egg-production have a bell-shaped relationship, and the association between protein and egg-production is better described by a 3D Lorenzian function. Additionally, the proposed 3D interpolation models produced good

  8. Roux-En-Y gastric bypass and sleeve gastrectomy does not affect food preferences when assessed by an ad libitum buffet meal

    DEFF Research Database (Denmark)

    Nielsen, Mette Søndergaard; Christensen, Bodil Just; Ritz, Christian

    2017-01-01

    BACKGROUND: 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. METHODS: 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...... at the buffet meal with 54% (4491 ± 208 kJ vs. 2083 ± 208 kJ, P 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...

  9. 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.

    Science.gov (United States)

    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 ( rabbits did not exhibit a different carcass yield but showed different carcass traits. Indeed, the ConsoResidual rabbits had a higher hind leg yield ( 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 ( 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 chilling loss ( = 0.0005) and the drip loss during 6 d ( feed seems to be less adversely correlated with carcass traits and meat quality traits but it leads to an increase in the live weight of the rabbits. Adversely, the selection on RFI, without affecting growth rate, would not modify age at slaughter because growth rate is not affected, but it might induce detrimental effects on meat quality.

  10. Influencia de la ingesta ad libitum de bebidas con diferente osmolaridad sobre algunas variables fisiológicas durante una actividad física de alta intensidad y larga duración. Influence of ad libitum intake of beverages with different osmolarities on some physiological parameters during a high-intensity, long-duration physical activity

    Directory of Open Access Journals (Sweden)

    Hilda Norha Jaramillo Londoño

    2006-01-01

    Full Text Available Objetivo: establecer la influencia de la ingesta ad libitum de diferentes bebidas hidratantes sobre el porcentaje de pérdida del peso corporal (%PC, el aumento de la frecuencia cardíaca (FC y la reducción porcentual del volumen plasmático (%VP en deportistas sometidos a una actividad física de alta intensidad y larga duración. Metodología: luego de nueve minutos de calentamiento, en banda rodante con velocidad equivalente al 50% de la frecuencia cardíaca de reserva (FCR, siguieron 88 minutos de carrera, durante la cual la velocidad se incrementó al 80% de la FCR; al final, 90 minutos de recuperación. No se hizo reposición hídrica durante el tratamiento deshidratado (DH; durante los tratamientos con hidratación se emplearon volúmenes similares, ingeridos ad libitum, de cada una de tres bebidas, a saber: hiperosmolar (Hiper, hipoosmolar (Hipo e isoosmolar (Iso. Resultados: se observó en cada uno de los tratamientos un aumento del porcentaje de pérdia del peso corporal (%PC (p<0,001 y de la FC (p< 0,05 al igual que una correlación entre el %PC y el incremento de la FC (p<0,000; en los tratamientos DH e Hiper hubo una reducción del volumen plasmático (%VP (p<0,05. Se observó interacción tiempo-tratamiento con el %PC. Conclusiones: la ingesta ad libitum fue menor que la cantidad recomendada en la literatura internacional, por lo que, probablemente, no se pudieron establecer los efectos de la osmolaridad de las bebidas hidratantes sobre las variables estudiadas. La magnitud del %PC, del incremento de la FC y de la reducción del %VP fueron proporcionales a la duración de la actividad física; la relación existente entre el %PC y la %VP se modificó por la osmolaridad de la bebida. Objetive: To establish the influence of ad libitum intake of hydrating beverages with different osmolarities on the percentage of body weight loss (%BW, the increase of heart rate (HR, and the percentage of plasma volume decrease (%PV in athletes

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

    Science.gov (United States)

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

    2009-01-31

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Christopher L. [University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, P.O. Box 38, Solomons, MD 20688 (United States)], E-mail: Rowe@cbl.umces.edu; Heyes, Andrew [University of Maryland Center for Environmental Science, Chesapeake Biological Laboratory, P.O. Box 38, Solomons, MD 20688 (United States); Hopkins, William [Department of Fisheries and Wildlife Sciences, Virginia Polytechnic Institute and State University, 100 Cheatham Hall, Blacksburg, VA 24061 (United States)

    2009-01-31

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

  13. 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

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Zhi; Liao, Wenhua; Yang, Yuanyuan [College of Resources and Environmental Sciences, Agricultural University of Hebei, 071000 Baoding (China); Gao, Zhiling, E-mail: zhilinggao@hotmail.com [College of Resources and Environmental Sciences, Agricultural University of Hebei, 071000 Baoding (China); Ma, Wenqi; Wang, Dianwu [College of Resources and Environmental Sciences, Agricultural University of Hebei, 071000 Baoding (China); Cao, Yufeng; Li, Jianguo [College of Animal Science and Technology, Agricultural University of Hebei, 071000 Baoding (China); Cai, Zhenjiang [Mechanical and Electric Engineering College, Agricultural University of Hebei, 071000 Baoding (China)

    2015-04-15

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

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

    Science.gov (United States)

    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.

  15. Effects of toasting blue lupins, soybeans or barley as supplement for high-yielding organic dairy cows fed grass-clover silage ad libitum

    DEFF Research Database (Denmark)

    Mogensen, Lisbeth; Lund, Peter; Kristensen, Troels

    2008-01-01

    degradability determined in situ for all three supplements. Compared to untreated lupins toasting of lupins tended (P = 0.10) to increase milk yield, whereas toasting of soybeans did not affect milk yield. Toasting of lupins decreased (P = 0.03) milk protein content (32.2 versus 32.7 g/kg), whereas toasting...... of soybeans did not affect milk protein content. ECM yield was significantly higher (P = 0.002) for cows fed toasted soybeans than for cows fed untreated soybeans (28.1 versus 26.4 kg ECM) whereas there was no significant effect on ECM yield from toasting lupins or barley. It can be concluded....... The supplement under investigation was: lupins in experiment 1, barley in experiment 2 and soybeans in experiment 3. The same forage mixture of grass-clover silage (84% of DM), grass pellets (11% of DM) and straw (5% of DM) was fed ad libitum in all the experiments. Toasting decreased effective rumen protein...

  16. Effect of polyethylene glycol 4000 supplementation on the performance of indigenous Pedi goats fed different levels of Acacia nilotica leaf meal and ad libitum Buffalo grass hay.

    Science.gov (United States)

    Motubatse, M R; Ng'ambi, J W; Norris, D; Malatje, M M

    2008-04-01

    In a first of two experiments, twenty yearling male Pedi goats weighing 21.3 +/- 0.5 kg live weight were used in a 37-day study in a 2 (levels of PEG 4000) x 2 (levels ofAcacia) Factorial arrangement in a Completely Randomised Design to determine the effect of the level of Acacia nilotica leaf meal supplementation plus 23 g polyethylene glycol 4000 on diet intake and digestibility, and growth rate of Pedi goats fed ad libitum Buffalo grass hay. Acacia nilotica leaf meal contained high amounts of total phenolics (2.04% DM) and low amounts of condensed tannins; both extracted (0.37% DM) and unextracted (1.83% DM). Supplementation with PEG 4000 increased (P diets similar to the actual ratios of the first experiment. Level of A. nilotica leaf meal supplementation plus 23 g PEG 4000 supplementation improved (P < 0.05) in vitro DM, OM and CP digestibilities where 120 g A. nilotica leaf meal was supplemented. Similarly, 23 g PEG 4000 supplementation also improved (P < 0.05) in vitro CP digestibility where 80 g A. nilotica leaf meal was supplemented. In vivo DM and OM digestibilities were best predicted from in vitro DM and OM digestibilities while in vivo CP was explained by in vitro OM and CP digestibilities. It is, therefore, concluded that in vitro DM and OM digestibilities have good capacity to predict in vivo DM and OM digestibilities while OM and CP digestibilities have good capacity to predict in vivo CP digestibility.

  17. Effects of intraduodenal infusion of the branched-chain amino acid leucine on ad libitum eating, gut motor and hormone functions, and glycemia in healthy men.

    Science.gov (United States)

    Steinert, Robert E; Landrock, Maria F; Ullrich, Sina S; Standfield, Scott; Otto, Bärbel; Horowitz, Michael; Feinle-Bisset, Christine

    2015-10-01

    Branched-chain amino acids (BCAAs), particularly leucine, act as nutrient signals regulating protein synthesis and degradation as well as glucose metabolism. In addition, leucine has been demonstrated in animal experiments to modulate eating and energy homeostasis. We aimed to characterize the effects of physiologic and supraphysiologic loads of intraduodenal leucine on eating, gut hormone and motor functions, and blood glucose in humans. Twelve lean men were studied on 3 occasions in a randomized, double-blind order. Antropyloroduodenal motility, plasma ghrelin, cholecystokinin, glucagon-like peptide 1, peptide YY, insulin, glucagon, blood glucose, appetite perceptions, and gastrointestinal symptoms were measured during 90-min intraduodenal infusions of leucine at 0.15 kcal/min (total 3.3 g, 13.5 kcal), 0.45 kcal/min (total 9.9 g, 40.5 kcal), or saline (control). Ad libitum eating from a buffet lunch was quantified immediately after the infusions. Leucine at 0.45 kcal/min inhibited eating (energy intake by ∼13%, P eating are probably not primarily mediated by changes in gut motor and hormone functions, with perhaps the exception of cholecystokinin. Instead, increased plasma leucine concentrations may be a potential signal mediating the eating-inhibitory effect of leucine. The study was registered as a clinical trial with the Australia and New Zealand Clinical Trial Registry (www.anzctr.org.au) as ACTRN12613000899741. © 2015 American Society for Nutrition.

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

    Science.gov (United States)

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

    2007-10-01

    Skewing of the sex ratio towards males occurs among pups born to mice fed a very high saturated fat (VHF) diet. In the present study, we tested whether the fat content of the VHF diet rather than the number of calories consumed is responsible for this effect. Eight-week-old NIH Swiss mice were placed on the VHF diet either ad libitum (VHF) or in a restricted manner (VHF-R). The VHF-R mice gained weight at a similar rate to controls fed a standard chow diet. Mice were bred at 15 wk and subsequently at 26 wk and 35 wk of age. Overall, the VHF, VHF-R, and control groups delivered 244, 242, and 274 pups, respectively, with male proportions of 0.60, 0.43, and 0.48, respectively. The pup sex ratios of the VHF group (favoring males) and VHF-R group (favoring females) each differed from 0.5 (P fat consumed. Since males fed the VHF diet had neither more Y-sperm nor sired more sons than daughters, the dietary effects are manifested exclusively through the female.

  19. Local e extensão da digestão em terneiros desmamados alimentados "Ad Libitum" com dietas ricas em concentrado contendo diferentes fontes de proteína suplementar Site and extent of digestion by weaned calves fed "Ad Libitum" on high concentrate-rich diets with different supplemental protein sources

    Directory of Open Access Journals (Sweden)

    Gilberto Vilmar Kozloski

    1999-06-01

    Full Text Available Foram utilizados nove terneiros da raça Holandesa (139 ± 2,4kg, fistulados no duodeno, em um delineamento experimental completamente casualizado para estudar o efeito da suplementação com diferentes fontes protéicas (2% de uréia ou 10% de farinha de carne na dieta total de dietas ricas em concentrado (milho e farelo de soja sobre o local e extensão da digestão do alimento, em condições de consumo ad libitum. A relação volumoso:concentrado das dietas foi de 30:70. A digestibilidade ruminal e total da matéria seca, matéria orgânica e nitrogênio, assim como o fluxo duodenal de nitrogênio microbiano e residual do alimento, e a eficiência da síntese protéica microbiana foram semelhantes nos dois tratamentos (P>0,10. A digestibilidade ruminal do amido também foi semelhante, mas a digestibilidade total foi menor no tratamento com uréia (PNine weaned Holstein calves (139 ± 2.4kg fitted with duodenal cannulas were used in a completly ramdomized design to study the effects of supplemental protein sources (2% of urea or 10% of meat meal of high concentrate diets (corn and soybean meal on site and extent of digestion of feed, in ad libitum feeding conditions. The forage:concentrate ratio was 30:70. The ruminal and total digestibility of dry matter, organic matter and nitrogen, as well as microbial and feed residual nitrogen duodenal flow, and the microbial protein synthesis efficiency were similar for both treatments (P>0.10. The ruminal digestibility of starch was also similar, but total digestibility was lower for urea treatment (P<0.10. However, this is probably due more to the limited capacity of ruminants to digest starch in the intestines than to an effect of the protein supplement. The use of urea or meat meal, as supplemental protein sources for corn and soybean meal based diets, formulated to supply the growth requirements of calves fed ad libitum, did not affect the digestion process.Thus, the choise of the protein

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Tobias Hoch

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

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

    Directory of Open Access Journals (Sweden)

    Joseph E Donnelly

    Full Text Available 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, or

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

    Science.gov (United States)

    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

    2017-04-14

    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 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.

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

    Science.gov (United States)

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

    2015-12-01

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

  5. Serum lipase activity and concentration during intravenous infusions of GLP-1 and PYY3-36 and after ad libitum meal ingestion in overweight men

    DEFF Research Database (Denmark)

    Schmidt, Julie Berg; Sjödin, Anders Mikael; Stevner, Lene Susanne

    2016-01-01

    the infusion and after intake of an ad libitum meal for measurement of serum lipase. Serum lipase levels measured by enzyme-linked immunosorbent assay (ELISA) following mono-infusions of GLP-1 and PYY3-36 were comparable to serum lipase levels following placebo (P = 0.054 and P = 0.873, respectively......To examine the effect on serum lipase activity and protein concentration of intravenous infusions of glucagon-like peptide-1 (GLP-1) and peptide YY (PYY3-36) and of an ad libitum meal in healthy overweight men. Twenty-five healthy, male subjects participated in this randomized, double......-blinded, placebo-controlled 4-arm crossover study (Body Mass Index (BMI): 29 ± 3 kg/m(2), age: 33 ± 9 years). On separate days, the subjects received a 150-min intravenous infusion of either (1) 0.8 pmol/kg/min PYY3-36, (2) 1.0 pmol/kg/min GLP-1, (3) 1 + 2, or (4) placebo. Samples were collected throughout...

  6. 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.

    Science.gov (United States)

    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, Pintake 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.

  7. Serum lipase activity and concentration during intravenous infusions of GLP‐1 and PYY3‐36 and after ad libitum meal ingestion in overweight men

    National Research Council Canada - National Science Library

    Schmidt, Julie B; Sjödin, Anders; Stevner, Lene S; Ritz, Christian; Michaelsen, Natasha B; Thomsen, Anne B; Holst, Jens J; Astrup, Arne

    2016-01-01

    ...‐min intravenous infusion of either (1) 0.8 pmol/kg/min PYY 3‐36 , (2) 1.0 pmol/kg/min GLP ‐1, (3) 1 + 2, or (4) placebo. Samples were collected throughout the infusion and after intake of an ad...

  8. Pattern of tissue deposition, gain and body composition of Nellore, F1 Simmental × Nellore and F1 Angus × Nellore steers fed at maintenance or ad libitum with two levels of concentrate in the diet

    Directory of Open Access Journals (Sweden)

    Ivanna Moraes de Oliveira

    2011-12-01

    Full Text Available Sixty 18-month-old steers (20 Nellore, 20 F1 Simmental × Nellore and 20 F1 Angus × Nellore with average body weight of 265.6±6.4 kg; 325.3±4.7 kg and 324.6±6.0 kg, respectively were used. The effects of feeding regime and genetic group on physical carcass composition, empty body composition, composition of the gain, as well as the pattern of tissue deposition were evaluated in this trial. The interaction between genetic group and feeding regime was not significant for any variable evaluated. Animals fed at the maintenance level produced carcass with larger proportions of bones and muscle than the animals fed ad libitum and Nellore animals had larger muscle portion and smaller adipose tissue portion on the carcass than the crossbred animals. Nellore animals and those fed at maintenance had smaller amount of total fat in the carcass than the crossbred animals and those fed ad libitum, respectively. Fat was deposited more pronouncedly in the intermuscular depot, followed by the visceral depot. The rate of deposition of the carcass tissues was smaller in the Nellore animals and in the animals fed the diet with concentrate allowance equivalent to 1% body weight (except for subcutaneous fat tissue, when compared with the crossbred animals and those fed the diet with 2% BW on concentrate, respectively. The rate of fat deposition on the visceral depot was larger in the F1 Angus × Nellore animals and on those fed the 2% of BW of concentrate diet when compared with F1 Simmental × Nellore animals and those fed the diet with the lowest concentrate allowance (1% BW.

  9. Influence of organic acids or fermentable carbohydrates on feeding value of urea treated wheat straw for Nili-Ravi buffalo bulls fed ad libitum diets

    Directory of Open Access Journals (Sweden)

    Wang-Shik Lee

    2010-02-01

    Full Text Available Four Nili-Ravi Buffalo bulls were used to study the influence of urea treated wheat straw (UTWS ensiled with organic acids or fermentable carbohydrates on nutrients digestibility and nitrogen (N balance. Four diets each having 50% dry matter (DM from UTWS ensiled with acetic acid (AD, formic acid (FD, acidified molasses (MD or corn steep liquor (CD were fed to ruminally cannulated bulls in a 4×4 Latin square design. Higher ruminal ammonia N at 3 and 6 h post prandial was observed with AD and FD diets. However, at 12 h post parandial, ammonia N was higher with MD and CD diets. The digestibility was similar across all treatments. The N balance was higher in bulls fed CD and MD diets than those fed AD and FD diets. Ensiling UTWS with fermentable carbohydrates compared to organic acids increases the N fixation in the matrix of cell wall fiber thus slowing its release at ruminal level that enhanced the N synchronization with carbon skeleton (fiber fermentation and this consequently minimizes N loss from the rumen. These results indicate that the UTWS ensiled with fermentable carbohydrates is of better feeding value for ruminants than UTWS ensiled with organic acids.

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

    Science.gov (United States)

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

    2017-07-01

    Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and, hence, better growth performance, the assumption has rarely been tested. This study compares the effects of time-restricted versus free access self-feeding on the growth, feeding behavior and daily digestive enzyme rhythms of Atlantic salmon ( Salmo salar). In an experiment that lasted 6 weeks, fish (109.9 g) were divided into two groups: group 1 had free access to a self-feeder (FA); group 2 received three meals per day (2 h per meal) at dawn, midday and dusk via a time-restricted self-feeder (TR). At the end of the experiment, the fish were sampled every 3 h over a 24-h period. The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase, while FA fish displayed no statistically significant rhythms ( P>0.05). Pepsin activity of TR fish also showed a significant daily rhythm ( P0.05). In conclusion, the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance, with the TR group showing comparatively poor blood glucose regulation.

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

    Science.gov (United States)

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

    2016-07-01

    Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and, hence, better growth performance, the assumption has rarely been tested. This study compares the Effects of time-restricted versus free access self-feeding on the growth, feeding behavior and daily digestive enzyme rhythms of Atlantic salmon (Salmo salar). In an experiment that lasted 6 weeks, fish (109.9 g) were divided into two groups: group 1 had free access to a self-feeder (FA); group 2 received three meals per day (2 h per meal) at dawn, midday and dusk via a time-restricted self-feeder (TR). At the end of the experiment, the fish were sampled every 3 h over a 24-h period. The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase, while FA fish displayed no statistically significant rhythms (P0.05). In conclusion, the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance, with the TR group showing comparatively poor blood glucose regulation.

  12. 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.

    Science.gov (United States)

    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

  13. Comportamento ingestivo de caprinos Moxotó e Canindé submetidos à alimentação à vontade e restrita = Ingestive behavior of Moxotó and Canindé goats submitted to ad libitum and restricted feeding

    Directory of Open Access Journals (Sweden)

    Valéria Louro Ribeiro

    2006-07-01

    Full Text Available O trabalho teve por objetivo avaliar o comportamento ingestivo de caprinos das raças Moxotó e Canindé, submetidos a dois níveis de alimentação. Foram utilizados 24 cabritos inteiros (12 Moxotó e 12 Canindé com idade média de quatro meses e peso vivo inicial médio de 15 kg, alojados em baias individuais, distribuídos no delineamentointeiramente casualizado, em um arranjo fatorial 2x2 (duas raças e dois níveis de alimentação e seis repetições. Os níveis de alimentação foram: à vontade (T1 e 30% de restrição em relação ao animal que recebia alimentação à vontade (T2. As observações comportamentais foram realizadas em intervalos de cinco minutos durante 24h. Os animais das raças Moxotó e Canindé não apresentaram diferença significativa (P>0,05 para as variáveis comportamentaisobservadas. Alimentação à vontade proporcionou maior atividade de alimentação e ruminação e menor tempo em ócio. As atividades de micção, defecação e procura por água foram influenciadas pela hora do dia.The aim of this study was to evaluate the intake behavior of Moxotóand Canindé breed goats when offered a diet at two levels of intake. Twenty-four noncastrated goats (12 Moxotó and 12 Canindé were used, with an average age of four months and an initial average weight of 15 kg. The goats were housed in individual pens, distributed using a completely randomized design, in a 2x2 factorial arrangement (two breeds and two levels of intake with six repetitions. The levels of intake offered were: ad libitum (T1 and 30% restriction (T2. The level of restriction was determined in relation to the amount consumed by animals on ad libitum intake. Behavioral observations were made at five-minute intervals during a 24hr period. There were no significant differences (p>0.05 in the observed behavioral variables between animals of the Moxotó and Canindé breeds. Feeding at the level of free-choice intake resulted in greater feeding and

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

    Science.gov (United States)

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

    2014-10-01

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

  15. An Efficient Channel Access Scheme for Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Syed Asad Hussain

    2017-01-01

    Full Text Available Vehicular Ad Hoc Networks (VANETs are getting more popularity due to the potential Intelligent Transport Systems (ITS technology. It provides many efficient network services such as safety warnings (collision warning, entertainment (video and voice, maps based guidance, and emergency information. VANETs most commonly use Road Side Units (RSUs and Vehicle-to-Vehicle (V2V referred to as Vehicle-to-Infrastructure (V2I mode for data accessing. IEEE 802.11p standard which was originally designed for Wireless Local Area Networks (WLANs is modified to address such type of communication. However, IEEE 802.11p uses Distributed Coordination Function (DCF for communication between wireless nodes. Therefore, it does not perform well for high mobility networks such as VANETs. Moreover, in RSU mode timely provision of data/services under high density of vehicles is challenging. In this paper, we propose a RSU-based efficient channel access scheme for VANETs under high traffic and mobility. In the proposed scheme, the contention window is dynamically varied according to the times (deadlines the vehicles are going to leave the RSU range. The vehicles with shorter time deadlines are served first and vice versa. Simulation is performed by using the Network Simulator (NS-3 v. 3.6. The simulation results show that the proposed scheme performs better in terms of throughput, backoff rate, RSU response time, and fairness.

  16. Access Point Security Service for wireless ad-hoc communication

    NARCIS (Netherlands)

    Scholten, J.; Nijdam, M.

    2006-01-01

    This paper describes the design and implementation of a security solution for ad-hoc peer-to-peer communication. The security solution is based on a scenario where two wireless devices require secure communication, but share no security relationship a priori. The necessary requirements for the secur

  17. Desempenho produtivo e eficiência bioeconômica de bovinos Nelore e Caracu selecionados para peso aos 378 dias de idade recebendo alimentação à vontade ou restrita Production and bioeconomic efficiency of Nellore and Caracu bulls selected to weight gain and fed ad libitum or restricted

    Directory of Open Access Journals (Sweden)

    Antonio Gesualdi Júnior

    2006-04-01

    Full Text Available Avaliou-se o desempenho de 56 bovinos machos não-castrados de três grupos genéticos, com idade média de 18 meses, submetidos à alimentação à vontade ou restrita, em confinamento. Doze animais foram abatidos no início do experimento e os demais (16 Nelore selecionados, 12 Nelore não-selecionados e 16 Caracu selecionados com peso vivo médio inicial de 404, 345 e 434 kg, respectivamente foram distribuídos em delineamento inteiramente casualizado, em esquema fatorial 2 x 3, composto por dois níveis de alimentação (restrito = consumo de 65 g de MS/kgPV0,75 por dia e ad libitum = fornecimento do alimento duas vezes ao dia e três grupos genéticos. O volumoso utilizado foi a silagem de milho e o concentrado foi constituído de milho moído, farelo de algodão, uréia, monensina e mistura mineral, com relação volumoso:concentrado 50:50. O abate foi realizado quando cada animal atingiu 4 mm gordura subcutânea à altura da 12ª costela, avaliada por ultra-som. Os grupos genéticos apresentaram ganhos médios diários de peso vivo e pesos de corpo vazio e de carcaça semelhantes, não havendo interação grupo genético × nível de alimentação. Os ganhos de peso vivo e os pesos de corpo vazio e de carcaça foram maiores nos animais alimentados ad libitum. Somente os consumos de matéria seca em kg/dia sofreram influência tanto do nível de alimentação quanto do grupo genético. Os animais Caracu apresentaram os maiores consumos, seguidos pelos Nelore selecionados. Os Nelores não-selecionados apresentaram melhor eficiência bionutricional e menor custo de produção da arroba que os demais grupos genéticos.Production of 56 feedlot bulls from three different genetic groups averaging 18 months of age and fed ad libitum or restricted was evaluated in this trial. Twelve animals were slaughtered at the beginning of the study and were used as references. The remaining 16 genetically selected Nellore, 12 ordinary Nellore, and 16

  18. myADS-arXiv: A fully customized, open access virtual journal

    Science.gov (United States)

    Kurtz, Michael; Eichhorn, Guenther; Henneken, Edwin; Accomazzi, Alberto; Grant, Carolyn; Thompson, Donna; Bohlen, Elizabeth; Murray, Stephen

    2007-03-01

    myADS-arXiv is a collaboration of the Astrophysics Data System group at the Smithsonian Astrophysical Observatory and the arXiv group at Cornell University. The myADS-arXiv service provides a listing of those articles in physics or astronomy which have been posted in the last week which are of most interest to you. In essence myADS-arXiv is a free, weekly, fully customized (for each individual user) open access virtual journal which covers the most important, most recent papers in physics and astronomy. myADS-arXiv follows the same format as the existing myADS-Astronomy and myADS-Physics notification services. These services provide access to the most interesting (to you) recent journal articles in physics and astronomy. These are done in collaboration with nearly every publisher of physics or astronomy journals, including APS, AIP, AAS, RAS, IoP, EDP, World Scientific, Wiley, Springer, and Elsevier.

  19. A TDMA based media access control protocol for wireless ad hoc networks

    Science.gov (United States)

    Yang, Qi; Tang, Biyu

    2013-03-01

    This paper presents a novel Time Division Multiplex Access (TDMA) based Media Access Control (MAC) protocol of wireless Ad Hoc network. To achieve collision free transmission, time slots in a MAC frame are cataloged into three types, that is access slot, control slot and traffic slot. Nodes in the network access to the network in the access slot, and an exclusive control is allocated subsequently. Data packets are transmission by dynamic schedule the traffic slots. Throughput and transmission delay are also analyzed by simulation experiment. The proposed protocol is capable of providing collision free transmission and achieves high throughput.

  20. User—dependent Perfect—scheduling Multiple Access (UPMA) for Wireless Ad Hoc Networ

    Institute of Scientific and Technical Information of China (English)

    LIJiandong; LIWeiying; YANGJiawei; WENGJiwei

    2003-01-01

    A new multiple access protocol for wireless Internet access, called user-dependent perfect-scheduling multiple access (UPMA), is proposed. Packet transmis-sions are scheduled according to the number of active users,packet queue length and round-robin service rule. The proposed self-organizing algorithm is used to determine the number of active users. Users in ad h0c network are divided into clusters by the self-organizing algorithm. In each cluster an independent UPMA is used. UPMA al-gorithms for star and ad hoc wireless network are given.Performance analysis shows that UPMA have stable and very high throughnut.

  1. Intelligent Security Auditing Based on Access Control of Devices in Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    XU Guang-wei; SHI You-qun; ZHU Ming; WU Guo-wen; CAO Qi-ying

    2006-01-01

    Security in Ad Hoc network is an important issue under the opening circumstance of application service. Some protocols and models of security auditing have been proposed to ensure rationality of contracting strategy and operating regulation and used to identify abnormal operation. Model of security auditing based on access control of devices will be advanced to register sign of devices and property of event of access control and to audit those actions. In the end, the model is analyzed and simulated.

  2. Efectos de la ingesta ad libitum de bebidas hidratantes sobre el peso corporal, la frecuencia cardíaca y el volumen plasmático durante una actividad física de alta intensidad y larga duración -Informe preliminar- Body weight, the heart rate, and the plasma volume during a high-intesity, long-duration run

    Directory of Open Access Journals (Sweden)

    Rubiela Flórez Manrique

    2004-02-01

    Full Text Available Objetivo: determinar la magnitud de la ingesta ad libitum de tres bebidas hidratantes de diferente osmolaridad y establecer sus efectos sobre el porcentaje de pérdida del peso corporal (PC, el aumento de la frecuencia cardíaca (FC y la reducción porcentual del volumen plasmático (VP en nueve deportistas con entrenamiento aeróbico, sometidos, bajo condiciones ambientales neutras, a una actividad física de alta intensidad 80% de la FC de reserva (FCR80 y larga duración 88 minutos. Metodología: el protocolo experimental se realizó en banda rodante, luego de nueve minutos de calentamiento, a una velocidad equivalente al 50% de la FCR y con una pendiente del 1%; siguieron 88 minutos de carrera, en tres intervalos, los dos iniciales de 29 minutos y el último de 30; la pendiente se mantuvo y la velocidad se incrementó al 80% de la FCR; finalmente, 90 minutos de recuperación, en tres intervalos de 30 minutos cada uno. No se hizo reposición hídrica durante el tratamiento deshidratado (DH; durante los tratamientos con hidratación se empleó un volumen similar de tres bebidas de diferente osmolaridad (H-I, H-II, H-III, el cual fue ingerido ad libitum. Resultados: durante la etapa de ejercicio la pérdida hídrica fue de 1.440 ml/h mientras que el volumen ingerido fue de 407 ml/h. Se observó, en cada uno de los tratamientos, una pérdida porcentual del PC (p<0,001; un incremento de la FC (p<0,05, y excepto con H-II y H-III una reducción porcentual del VP (p<0,05. No hubo diferencias intertratamientos en el porcentaje de la pérdida del PC, en el aumento de la FC ni en la reducción porcentual del VP. Conclusiones: la ingesta ad libitum fue menor que la cantidad recomendada internacionalmente por lo que, probablemente, no se pudieron establecer los efectos de la osmolaridad de las bebidas hidratantes sobre las variables estudiadas. Estos hallazgos nos obligan a revisar las prácticas de hidratación de nuestros deportistas ya que, al parecer

  3. A survey of medium access control protocols for wireless ad hoc networks

    Directory of Open Access Journals (Sweden)

    Elvio João Leonardo

    2004-01-01

    Full Text Available A number of issues distinguishes Medium Access Control (MAC protocols for wireless networks from those used in wireline systems. In addition, for ad-hoc networks, the characteristics of the radio channel, the diverse physical-layer technologies available and the range of services envisioned make it a difficult task to design an algorithm to discipline the access to the shared medium that results efficient, fair, power consumption sensitive and delay bound. This article presents the current “state-of-art” in this area, including solutions already commercially available as well as those still in study.

  4. A Novel Medium Access Control for Ad hoc Networks Based on OFDM System

    Institute of Scientific and Technical Information of China (English)

    YU Yi-fan; YIN Chang-chuan; YUE Guang-xin

    2005-01-01

    Recently, hosts of Medium Access Control (MAC) protocols for Ad hoc radio networks have been proposed to solve the hidden terminal problem and exposed terminal problem. However most of them take into no account the interactions between physical (PHY) system and MAC protocol. Therefore, the current MAC protocols are either inefficient in the networks with mobile nodes and fading channel or difficult in hardware implementation. In this paper, we present a novel media access control for Ad hoc networks that integrates a media access control protocol termed as Dual Busy Tone Multiple Access (DBTMA) into Orthogonal Frequency Division Multiplexing (OFDM) system proposed in IEEE 802.11a standard. The analysis presented in the paper indicates that the proposed MAC scheme achieves performance improvement over IEEE 802.11 protocol about 25%~80% especially in the environment with high mobility and deep fading. The complexity of the proposed scheme is also lower than other implementation of similar busy tone solution. Furthermore, it is compatible with IEEE 802.11a networks.

  5. A concurrent access MAC protocol for cognitive radio ad hoc networks without common control channel

    Science.gov (United States)

    Timalsina, Sunil K.; Moh, Sangman; Chung, Ilyong; Kang, Moonsoo

    2013-12-01

    Cognitive radio ad hoc networks (CRAHNs) consist of autonomous nodes that operate in ad hoc mode and aim at efficient utilization of spectrum resources. Usually, the cognitive nodes in a CRAHN exploit a number of available channels, but these channels are not necessarily common to all nodes. Such a network environment poses the problem of establishing a common control channel (CCC) as there might be no channel common to all the network members at all. In designing protocols, therefore, it is highly desirable to consider the network environment with no CCC. In this article, we propose a MAC protocol called concurrent access MAC (CA-MAC) that operates in the network environment with no CCC. The two devices in a communication pair can communicate with each other even if they have only one common channel available. Therefore, the problems with CCC (such as channel saturation and denial of service attacks) can also be resolved. In CA-MAC, channel accesses are distributed over communication pairs, resulting in increased network connectivity. In addition, CA-MAC allows different communication pairs to access multiple channels concurrently. According to our performance study, CA-MAC provides higher network connectivity with shorter channel access delay compared to SYN-MAC, which is the conventional key MAC protocol for the network environment with no CCC, resulting in better network throughput.

  6. A test bed for the future access control system the AD Project

    CERN Document Server

    Scibile, L

    1999-01-01

    This paper describes the design, management and development of the new access control system for the Antiproton Deceleration experimental area, called the AD Project. As this project includes all the elements for the industrial evolution of the present access control system it is an ideal test bed for future access systems. The adoption of new technologies and techniques are described, and the benefits and the shortfalls are highlighted. The open redundant architecture solution, based on a PROFIBUS network and standard industrial components (HP-UNIX, Siemens S7 PLC, Siemens Industrial PC, door locks), guarantees reliability, safety and optimal integration. The project team took advantage of the Goal Directed Project Management technique and managed to define a clear and effective strategy.

  7. Effects of feeding level and access to rooting material on behaviour of growing pigs in situations with reduced feeding space and delayed feeding

    DEFF Research Database (Denmark)

    Jensen, Margit Bak; Pedersen, Lene Juul

    2010-01-01

    Seventy-two pigs, housed in groups of four, were allocated to either (1) ad libitum feeding with access to wood chip, (2) restrictive feeding with access to wood chip or (3) restrictive feeding without access to wood chip. The effects of feeding level (treatment 1 vs. 2) and access to wood chip (...

  8. Cigarette-by-cigarette satisfaction during ad libitum smoking.

    Science.gov (United States)

    Shiffman, Saul; Kirchner, Thomas R

    2009-05-01

    Smoking is thought to produce immediate reinforcement, and subjective satisfaction with smoking is thought to influence subsequent smoking. The authors used ecological momentary assessment (A. A. Stone & S. Shiffman, 1994) to assess cigarette-by-cigarette smoking satisfaction in 394 heavy smokers who subsequently attempted to quit. Across 14,882 cigarettes rated, satisfaction averaged 7.06 (0-10 scale), but with considerable variation across cigarettes and individuals. Women and African American smokers reported higher satisfaction. More satisfied smokers were more likely to lapse after quitting (HR = 1.1, p < .03), whereas less satisfied smokers derived greater benefit from patch treatment to help them achieve abstinence (HR = 1.23, p < .001). Cigarettes smoked in positive moods were more satisfying, correcting for mood at the time of rating. The best predictor of subsequent smoking satisfaction was the intensity of craving prior to smoking. Understanding subjective smoking satisfaction provides insight into sources of reinforcement for smoking.

  9. The effect of viscosity on ad libitum food intake

    NARCIS (Netherlands)

    Zijlstra, N.; Mars, M.; Wijk, de R.A.; Westerterp-Plantenga, M.; Graaf, de C.

    2008-01-01

    Background: Energy-yielding liquids elicit weak suppressive appetite responses and weak compensatory responses, suggesting that liquid calories might lead to a positive energy balance. However, data is often derived from foods differing in many characteristics other than viscosity. Objective: To

  10. Craving in intermittent and daily smokers during ad libitum smoking.

    Science.gov (United States)

    Shiffman, Saul; Dunbar, Michael S; Li, Xiaoxue; Scholl, Sarah M; Tindle, Hilary A; Anderson, Stewart J; Ferguson, Stuart G

    2014-08-01

    This study aimed to assess average and peak craving intensity among nondaily intermittent smokers (ITS) in smoking episodes and when not smoking compared to that of daily smokers (DS). Two hundred and twelve ITS and 194 DS monitored their smoking and craving for 3 weeks using Ecological Momentary Assessment methods. Craving was assessed (0-100 scale) when subjects lit a cigarette and at random times when not smoking; 48,469 observations were analyzed using generalized estimating equations. ITS experienced craving, including intense craving; their 95th percentile intensity averaged 77.7 ± 22.5 out of 100 (higher among DS: 89.1 ± 14.5). ITS reported lower craving than DS, both when smoking and when not smoking. In both groups, craving was less intense when not smoking (DS: 71.1 ± 20.7 vs. 59.83 ± 21.97; ITS: 59.91 ± 23.03 vs. 26.63 ± 19.87), but the difference was significantly greater among ITS. Among ITS, the probability of smoking rose continuously as craving increased over the full range of the scale. In contrast, among DS the probability of smoking rose until the midpoint of the scale, after which the relationship flattened. Findings were mostly similar for ITS with and without a history of past daily smoking. ITS do experience craving, including intense craving. The relationship between craving and smoking is stronger among ITS because DS experience moderate craving even between cigarettes. In contrast, ITS appear to experience craving in limited situations associated with smoking, suggesting that their craving and smoking may be driven by transient cues rather than endogenous needs. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Ractopamine for finishing barrows fed restricted or ad libitum diets: performance and nitrogen balance Ractopamina para suínos em terminação recebendo ração restrita ou à vontade: desempenho e balanço de nitrogênio

    Directory of Open Access Journals (Sweden)

    Vinícius de Souza Cantarelli

    2009-12-01

    Full Text Available Supplementation of 5 ppm of ractopamine, associated or not to feed restriction in diets with a high total lysine content (1.04% was evaluated on performance and nitrogen balance. In experiment 1, 60 hybrid castrated male swine (76.2 ± 2.3 kg were housed in pairs according to a randomized complete block design in a factorial treatment arrangement (2 ×2 + 1 with or without ractopamine supplementation, two forms of feeding, ad libitum and feed restriction with 1.04% lysine, and an additional treatment (control, with ad libitum feed without ractopamine with 0.8% lysine, amounting to five treatments and six replications. The final live weight, daily weight gain, daily feed intake and feed conversion for 28 days were evaluated. There were improvements in supplementation with ractopamine for final live weight, daily weight gain and feed conversion. The ad libitum feeding improved both final live weight and daily weight gain compared with ractopamine. Compared with the control, there was a decrease in feed conversion with ractopamine supplementation and improvement for final weight (FW in the treatment with the ractopamine and ad libitum feed. In experiment 2, 30 hybrid castrated male swine (74.1 ± 2.5 kg were housed in metabolism cages and fed the same experimental treatments to evaluate the percentages of absorbed nitrogen (Nabs, retained nitrogen (Nret, nitrogen retained from the absorbed nitrogen (Nret/Nabs and the plasma urea concentration at 14 and 28 days. At 14 days, there was an increase in the Nret/Nabs and plasma urea concentration with ractopamine supplementation. Compared with the control, there was a decrease in the plasma urea concentration for feed restriction with ractopamine. At 28 days, there was an increase in the Nret/Nabs with ractopamine supplementation. Thus supplementation with 5 ppm ractopamine improved the performance and efficiency of swine nitrogen use. Feed restriction interfered negatively in weight gain, but it

  12. An extended smart utilization medium access control (ESU-MAC) protocol for ad hoc wireless systems

    Science.gov (United States)

    Vashishtha, Jyoti; Sinha, Aakash

    2006-05-01

    The demand for spontaneous setup of a wireless communication system has increased in recent years for areas like battlefield, disaster relief operations etc., where a pre-deployment of network infrastructure is difficult or unavailable. A mobile ad-hoc network (MANET) is a promising solution, but poses a lot of challenges for all the design layers, specifically medium access control (MAC) layer. Recent existing works have used the concepts of multi-channel and power control in designing MAC layer protocols. SU-MAC developed by the same authors, efficiently uses the 'available' data and control bandwidth to send control information and results in increased throughput via decreasing contention on the control channel. However, SU-MAC protocol was limited for static ad-hoc network and also faced the busy-receiver node problem. We present the Extended SU-MAC (ESU-MAC) protocol which works mobile nodes. Also, we significantly improve the scheme of control information exchange in ESU-MAC to overcome the busy-receiver node problem and thus, further avoid the blockage of control channel for longer periods of time. A power control scheme is used as before to reduce interference and to effectively re-use the available bandwidth. Simulation results show that ESU-MAC protocol is promising for mobile, ad-hoc network in terms of reduced contention at the control channel and improved throughput because of channel re-use. Results show a considerable increase in throughput compared to SU-MAC which could be attributed to increased accessibility of control channel and improved utilization of data channels due to superior control information exchange scheme.

  13. Comportamento ingestivo de caprinos Moxotó e Canindé submetidos à alimentação à vontade e restrita - DOI: 10.4025/actascianimsci.v28i3.50 Ingestive behavior of Moxotó and Canindé goats submitted to ad libitum and restricted feeding - DOI: 10.4025/actascianimsci.v28i3.50

    Directory of Open Access Journals (Sweden)

    Francisco Fernando Ramos de Carvalho

    2006-01-01

    Full Text Available O trabalho teve por objetivo avaliar o comportamento ingestivo de caprinos das raças Moxotó e Canindé, submetidos a dois níveis de alimentação. Foram utilizados 24 cabritos inteiros (12 Moxotó e 12 Canindé com idade média de quatro meses e peso vivo inicial médio de 15 kg, alojados em baias individuais, distribuídos no delineamento inteiramente casualizado, em um arranjo fatorial 2x2 (duas raças e dois níveis de alimentação e seis repetições. Os níveis de alimentação foram: à vontade (T1 e 30% de restrição em relação ao animal que recebia alimentação à vontade (T2. As observações comportamentais foram realizadas em intervalos de cinco minutos durante 24h. Os animais das raças Moxotó e Canindé não apresentaram diferença significativa (P>0,05 para as variáveis comportamentais observadas. Alimentação à vontade proporcionou maior atividade de alimentação e ruminação e menor tempo em ócio. As atividades de micção, defecação e procura por água foram influenciadas pela hora do diaThe aim of this study was to evaluate the intake behavior of Moxotó and Canindé breed goats when offered a diet at two levels of intake. Twenty-four noncastrated goats (12 Moxotó and 12 Canindé were used, with an average age of four months and an initial average weight of 15 kg. The goats were housed in individual pens, distributed using a completely randomized design, in a 2x2 factorial arrangement (two breeds and two levels of intake with six repetitions. The levels of intake offered were: ad libitum (T1 and 30% restriction (T2. The level of restriction was determined in relation to the amount consumed by animals on ad libitum intake. Behavioral observations were made at five-minute intervals during a 24hr period. There were no significant differences (p>0.05 in the observed behavioral variables between animals of the Moxotó and Canindé breeds. Feeding at the level of free-choice intake resulted in greater feeding and

  14. Características da carcaça e viabilidade econômica do uso de cloridrato de ractopamina para suínos em terminação com alimentação à vontade ou restrita Carcass characteristics and economic viability of the use of ractopamine for finishing swine with ad libitum or restricted feeding

    Directory of Open Access Journals (Sweden)

    Vinícius de Souza Cantarelli

    2009-06-01

    design in factorial scheme 2 x 2 + 1 (with or without RAC in diets with 1.04% of total lysine; ad libitum or feed restriction of 15% and an additional treatment - control - ad libitum, without RAC containing 0.8% of lysine - standard diet, totalizing five treatments and six replicates. The addiction of RAC per se increased the loin eye area, the meat percentage, the carcass meat:fat ratio, the allowance index, the gross earnings and the production net earnings and decreased the animals backfat thickness. When associated with feed restriction, the RAC decreased the carcass fat percentage. Compared to standard diet, the RAC increased the carcass yield, the carcass meat percentage and the allowance index paid to the producer and decreased the backfat thickness. The RAC associated at the feed restriction decreased the fat carcass percentage and increased the carcass meat:fat ratio and the gross earnings. Thus, the supplementation with 5ppm of RAC, associated or no at the feed restriction, improves the carcass characteristics and the economic viability of production.

  15. NRZ versus RZ over Absolute Added Correlative coding in optical metro-access networks

    Science.gov (United States)

    Dong-Nhat, Nguyen; Elsherif, Mohamed A.; Le Minh, Hoa; Malekmohammadi, Amin

    2017-03-01

    This paper comparatively investigates the transmission performance of absolute added correlative coding (AACC) using non-return-to-zero (NRZ) and return-to-zero (RZ) pulse shapes with a binary intensity modulation direct detection receiver in 40 Gb/s optical metro-access networks operating at 1550 nm. It is shown that, for AACC transmission, the NRZ impulse shaping is superior in comparison to RZ in spectral efficiency, dispersion tolerance, residual dispersion and self-phase modulation (SPM) tolerance. However, RZ-AACC experiences a 1-2 dB advantage in receiver sensitivity over NRZ-AACC for back-to-back configuration as well as after 300-km single-mode fiber delivery.

  16. Directional Medium Access Control (MAC Protocols in Wireless Ad Hoc and Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    David Tung Chong Wong

    2015-06-01

    Full Text Available This survey paper presents the state-of-the-art directional medium access control (MAC protocols in wireless ad hoc and sensor networks (WAHSNs. The key benefits of directional antennas over omni-directional antennas are longer communication range, less multipath interference, more spatial reuse, more secure communications, higher throughput and reduced latency. However, directional antennas lead to single-/multi-channel directional hidden/exposed terminals, deafness and neighborhood, head-of-line blocking, and MAC-layer capture which need to be overcome. Addressing these problems and benefits for directional antennas to MAC protocols leads to many classes of directional MAC protocols in WAHSNs. These classes of directional MAC protocols presented in this survey paper include single-channel, multi-channel, cooperative and cognitive directional MACs. Single-channel directional MAC protocols can be classified as contention-based or non-contention-based or hybrid-based, while multi-channel directional MAC protocols commonly use a common control channel for control packets/tones and one or more data channels for directional data transmissions. Cooperative directional MAC protocols improve throughput in WAHSNs via directional multi-rate/single-relay/multiple-relay/two frequency channels/polarization, while cognitive directional MAC protocols leverage on conventional directional MAC protocols with new twists to address dynamic spectrum access. All of these directional MAC protocols are the pillars for the design of future directional MAC protocols in WAHSNs.

  17. A Novel Multiple Access Protocol for Mobile Ad Hoc Network with Smart Antennas

    Institute of Scientific and Technical Information of China (English)

    YANGJun; LIJiandong; ZHOUXiaodong

    2004-01-01

    The approach to employ smart antennas in Mobile ad hoc network (MANET) nodes is presented. An adaptive beamforming-Carrier-Sense multiple access/collison avoidance) (ABF-CSMA/CA) protocol is proposed. In the ABF-CSMA/CA, Request-to-Send/Clear-to-Send (RTS/CTS) dialogue is used to distribute channel reservation information. Training sequences are transmitted just before RTS and CTS packets, so the Temporal reference beamforming (TRB) can be performed by the source node and the destination node.An improved virtual carrier-sense mechanism is also proposed to enhance Collision avoidance (CA) and obtain efficient Space division multiple access (SDMA). In this scheme, every node has two kinds of Network allocation vector (NAV): an oNAV maintains the interval of ongoing transmission of neighbors whose smart antennas operate in omnidirectional mode, and multiple bNAVs maintain those intervals of neighbors whose smart antennas operate in beamforming mode. Theoretical analysis of channel utilization of the proposed protocol is presented. Results show that ABF-CSMA/CA protocol combining with smart antennas can provide higher channel utilization.

  18. Access control based on clustering in Ad Hoc networks%Ad Hoc网络中基于分簇的访问控制方案

    Institute of Scientific and Technical Information of China (English)

    程帆; 王晓明

    2012-01-01

    This paper proposes an access control scheme for cluster-based Ad Hoc networks. This scheme classifies the resources and nodes into levels to provide differentiated privileges access control. A dynamic access control mechanism is implemented based on the simple effective trust model and incentive mechanism which can change the node' s privilege. The cluster-head proxy is developed to access the resource that enhances security and fully utilizes the quality resources. Simulations result show that this scheme is of high efficiency and little communication.%基于分簇结构提出一种适用于Ad Hoc网络的访问控制方案.通过将资源和节点分等级来实现不同权限的访问控制;采用简单有效的信誉模型和激励机制来改变节点的权限,实现了动态的访问控制;通过簇头代理访问资源,增强了网络的安全性,并且使网络中优质资源得到充分利用.仿真结果表明,该方案有较高的效率和较少的通信量.

  19. A Combined Solution for Routing and Medium Access Control Layer Attacks in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    R. Murugan

    2010-01-01

    Full Text Available Problem statement: In Mobile Ad hoc Network (MANET, both the routing layer and the Medium Access Control (MAC layer are vulnerable to several attacks. There are very few techniques to detect and isolate the attacks of both these layers simultaneously. In this study, we developed a combined solution for routing and MAC layer attacks. Approach: Our approach, makes use of three techniques simultaneously which consists of a cumulative frequency based detection technique for detecting MAC layers attacks, data forwarding behavior based detection technique for detecting packet drops and message authentication code based technique for packet modification. Results: Our combined solution presents a reputation value for detecting the malicious nodes and isolates them from further network participation till its revocation. Our approach periodically checks all nodes, including the isolated nodes, at regular time period λ. A node which recovers from its misbehaving condition is revoked to its normal condition after the time period λ. Conclusion/Recommendations: By simulation results, we show that our combined solution provides more security by increased packet delivery ratio and reduced packet drops. We also shown that our approach has less overhead compared to the existing technique.

  20. Salt intensity does not affect ad libtum intake of similar pleasant tomato soup

    NARCIS (Netherlands)

    Bolhuis, Dieuwerke; Lakemond, C.M.M.; Wijk, de R.A.; Luning, P.; Graaf, de C.

    2010-01-01

    The aim of the present study was to investigate the effect of salt intensity on ad libitum intake of tomato soup. Secondly, the perceived salt intensity before and after ad libitum intake of tomato soups with varying saltiness concentrations was assessed. Subjects (n = 48) ate in duplo ad libitum fr

  1. Adaptive changes in the appetite, growth and feeding behaviour of pony mares offered ad libitum access to a complete diet in either a pelleted or chaff-based form

    DEFF Research Database (Denmark)

    Argo, C.M.; Cox, J.E.; Lockyer, C.

    2002-01-01

    stabled ponies to re-establish natural feeding patterns and offers a viable alternative to meal and forage feeding. The more slowly ingested chaff form maximized time spent feeding and limited changes in DEI during the introductory period. Although CS and ADG increased over the first 4 weeks, growth...... (23 (s.e. 1.2) per bite, P spent more time feeding (0.50 (s.e. 1.3) of the time, P ...-detergent fibre (NDF, 0.53) and gross energy (GE) were neither altered by food processing nor time. Apparent digestibilities (DM, 0.49; GE, 0.50; NDF, 0.40 in period 1) of the pelleted and chaff- based diets were similar within periods but decreased (P

  2. A cross-layer scheme for medium access control with QoS guaranteeing for Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    YU Yi-fan; YIN Chang-chuan; YUE Guang-xin

    2006-01-01

    Ample medium access control (MAC) protocols for Ad hoc networks have been proposed. However, most of them do not take into account the interactions between the physical (PHY) layer and the MAC layers. Therefore, their efficiency and feasibility are greatly limited. In this article, we present a novel MAC protocol for Ad hoc networks according to the idea of cross-layer design. The proposed protocol combines an MAC protocol termed dual busy tone multiple access (DBTMA) with Orthogonal frequency division multiplexing (OFDM) system in IEEE 802.11a standard. The analysis showed that the proposed protocol provides higher throughput and is more flexible than previous MAC protocols. In addition, it can provide Quality of Service(QoS) guarantee to the packets with different delay requirements in the presence of hidden terminals.

  3. Cognitive Self-Scheduled Mechanism for Access Control in Noisy Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Mario Manzano

    2015-01-01

    Full Text Available Within the challenging environment of intelligent transportation systems (ITS, networked control systems such as platooning guidance of autonomous vehicles require innovative mechanisms to provide real-time communications. Although several proposals are currently under discussion, the design of a rapid, efficient, flexible, and reliable medium access control mechanism which meets the specific constraints of such real-time communications applications remains unsolved in this highly dynamic environment. However, cognitive radio (CR combines the capacity to sense the radio spectrum with the flexibility to adapt to transmission parameters in order to maximize system performance and has thus become an effective approach for the design of dynamic spectrum access (DSA mechanisms. This paper presents the enhanced noncooperative cognitive division multiple access (ENCCMA proposal combining time division multiple access (TDMA and frequency division multiple access (FDMA schemes with CR techniques to obtain a mechanism fulfilling the requirements of real-time communications. The analysis presented here considers the IEEE WAVE and 802.11p as reference standards; however, the proposed medium access control (MAC mechanism can be adapted to operate on the physical layer of different standards. The mechanism also offers the advantage of avoiding signaling, thus enhancing system autonomy as well as behavior in adverse scenarios.

  4. A Globally Accessible List (GAL Based Recovery Concept In Mobile Ad-hoc Network

    Directory of Open Access Journals (Sweden)

    A.K.Daniel,

    2011-04-01

    Full Text Available A mobile ad-hoc network is a mobile, multi-hop wireless network which is capable of autonomous operation whose primary role is to provide a reliable end to end communication between nodes in the network.However achieving reliable transmission in mobile wireless network is crucial due to change in the network topology caused by node mobility. Modern communication network is becoming increasing & diverse. This is the consequence of an increasing array of devices & services both wired & wireless. There are various protocols to facilitate communication in ad hoc network like DSR and TORA. However these approaches end up in the inefficient utilization of resources after link failure and congestion. This paper proposes an approach to get over this problem .We have added some static nodes which only keeps information related to the current working path and also helps in quick recovery in case of link failure .

  5. A distributed Synchronous reservation multiple access control protocol for mobile Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yanling; SUN Xianpu; LI Jiandong

    2007-01-01

    This study proposes a new multiple access control protocol named distributed synchronous reservation multiple access control protocol.in which the hidden and exposed terminal problems are solved,and the quality of service(QoS)requirements for real-time traffic are guaranteed.The protocol is founded on time division multiplex address and a different type of traffic is assigned to difierent priority,according to which a node should compete for and reserve the free slots in a different method.Moreover,there is a reservation acknowledgement process before data transmit in each reserved slot,so that the intruded terminal problem is solved.The throughput and average packets drop probability of this protocol are analyzed and simulated in a fully connected network.the results of which indicate that this protocol is efficient enough to support the real-time traffic.and it is more suitable to MANETs.

  6. ADNP-CSMA Random Multiple Access protocol application with the function of monitoring in Ad Hoc network

    Directory of Open Access Journals (Sweden)

    Zhan Gang

    2016-01-01

    Full Text Available In Ad Hoc networks,the net work of mobile nodes exchange information with their wireless transceiver equipment,the network throughput is in increased,compared to other such multiple hops network.Moreover along with the rapid development of modern information,communication business also will be increase.However,the access and adaptive of previous CSMA protocol are insufficient.According to these properties,this paper presents a kind of adaptive dual clock with monitoring function P-CSMA random multiple access protocol(ADNP-CSMA,and discusses two kinds of P-CSMA.ACK with monitoring function is introduced to maintain the stability of the whole system,and the introduction of dual clock mechanism reduces the channel of idle period.It calculate the system throughput expression through the method of average period,and the simulation results show that the system is constant in the case of high load throughput.

  7. PERFORMANCE OF OPPORTUNISTIC SPECTRUM ACCESS WITH SENSING ERROR IN COGNITIVE RADIO AD HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    N. ARMI

    2012-04-01

    Full Text Available Sensing in opportunistic spectrum access (OSA has a responsibility to detect the available channel by performing binary hypothesis as busy or idle states. If channel is busy, secondary user (SU cannot access and refrain from data transmission. SU is allowed to access when primary user (PU does not use it (idle states. However, channel is sensed on imperfect communication link. Fading, noise and any obstacles existed can cause sensing errors in PU signal detection. False alarm detects idle states as a busy channel while miss-identification detects busy states as an idle channel. False detection makes SU refrain from transmission and reduces number of bits transmitted. On the other hand, miss-identification causes SU collide to PU transmission. This paper study the performance of OSA based on the greedy approach with sensing errors by the restriction of maximum collision probability allowed (collision threshold by PU network. The throughput of SU and spectrum capacity metric is used to evaluate OSA performance and make comparisons to those ones without sensing error as function of number of slot based on the greedy approach. The relations between throughput and signal to noise ratio (SNR with different collision probability as well as false detection with different SNR are presented. According to the obtained results show that CR users can gain the reward from the previous slot for both of with and without sensing errors. It is indicated by the throughput improvement as slot number increases. However, sensing on imperfect channel with sensing errors can degrade the throughput performance. Subsequently, the throughput of SU and spectrum capacity improves by increasing maximum collision probability allowed by PU network as well. Due to frequent collision with PU, the throughput of SU and spectrum capacity decreases at certain value of collision threshold. Computer simulation is used to evaluate and validate these works.

  8. Freely accessible water does not decrease consumption of ethanol liquid diets.

    Science.gov (United States)

    de Fiebre, NancyEllen C; de Fiebre, Christopher M

    2003-02-01

    In experimental studies, liquid ethanol diets are usually given as the sole source of nutrition and fluid. Two series of experiments were conducted to examine the effect of freely accessible water on the consumption of ethanol liquid diets in male Long-Evans rats. The consumption of diets and subsequent learning ability of rats were first examined in animals given twice-daily saline injections. One group received diet with no access to water for 12 weeks and was subsequently given free access to water with diets for an additional 12 weeks. A second group was given diet and water ad libitum for 24 weeks. Control animals received an isocaloric sucrose-containing diet (with or without ad libitum access to water). Subsequently, rats were tested for active avoidance learning. In the first 12 weeks, animals with ad libitum access to water drank more diet than did water-restricted animals, and previously water-restricted animals increased their diet consumption when access to water was freely available. All water-restricted animals, in both ethanol- and sucrose-treated groups, showed deficits in active avoidance learning, whereas only ethanol-treated animals in groups with ad libitum access to water showed learning deficits. In the second series of experiments, the effect of saline injections on diet consumption, both in the presence and absence of water, was examined. Although saline injections were associated with decreased diet consumption, there was no effect of free access to water. No differences in blood ethanol concentration were seen among groups. Findings obtained from both series of studies demonstrate that consumption of a Sustacal-based liquid ethanol diet does not decrease if access to water is freely available.

  9. Modified Distributed Medium Access Control Algorithm Based on Multi-Packets Reception in Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    ZHENG Qing; YANG Zhen

    2005-01-01

    Based on the Multi-Packet Reception(MPR)capability at the physical layer and the Distributed Coordination Function(DCF)of the IEEE 802.11 MAC protocol,we propose a modified new solution about WAITING mechanism to make full use of the MPR capability in this paper,which is named as modified distributed medium access control algorithm.We describe the details of each step of the algorithm after introducing the WAITING mechanism.Then,we also analyze how the waiting-time affects the throughput performance of the network.The network simulator NS-2 is used to evaluate the throughput performance of the new WAITING algorithm and we compare it with IEEE 802.11 MAC protocol and the old WAITING algorithm.The experimental results show that our new algorithm has the best performance.

  10. Improvement in Medium Access Control protocol based on new contention scheme for wireless ad hoc network

    Directory of Open Access Journals (Sweden)

    C.Ellammal

    2012-05-01

    Full Text Available In todays wireless networks, stations using the IEEE 802.11 standard contend for the channel using the Distributed Coordination Function (DCF. Research has shown that DCF€™s performance degrades especially with the large number of stations. This becomes more concerning due to the increasing proliferation of wireless devices. In this paper, we present a Medium Access Control (MAC scheme for wireless LANs and compare its performance to DCF . Our scheme, which attempts to resolve the contention in a constant number of slots (or constant time, is called CONSTI. The contention resolution happens over a predefined number of slots. In a slot, the stations probabilistically send a jam signal on the channel. The stations listening retire if they hear a jam signal. The others continue to the next slot. Over several slots, we aim to have one station remaining in the contention, which will then transmit its data. We find the optimal parameters of CONSTI and present an analysis on its performance.

  11. Adding dental therapists to the health care team to improve access to oral health care for children.

    Science.gov (United States)

    Nash, David A

    2009-01-01

    Oral Health in America: A Report of the Surgeon General, and the subsequent National Call to Action to Promote Oral Health, contributed significantly to raising awareness regarding the lack of access to oral health care by many Americans, especially minority and low-income populations, with resulting disparities in oral health. The problem is particularly acute among children. The current dental workforce in the United States is inadequate to meet the oral health care needs of children. It is inadequate in terms of numbers of dentists, as well as their geographic distribution, ethnicity, education, and practice orientation. Dental therapists, paraprofessionals trained in a 2 academic-year program of postsecondary education, have been employed internationally to improve access to oral health care for children. Research has documented that utilizing dental therapists is a cost-effective method of providing quality oral health care for children. Dental therapists have recently been introduced in Alaska by the Alaska Native Tribal Health Consortium. Dental therapists could potentially care for children in dental offices, public health clinics, and school systems, as well as in the offices of pediatricians and family physicians. Adding dental therapists to the health care team would be a significant strategy for improving access to care for children and reducing oral health disparities.

  12. Connection Sharing Scheme of Ad hoc Network Accessing to Internet%Ad hoc网络接入Internet的连接共享机制

    Institute of Scientific and Technical Information of China (English)

    王海涛

    2005-01-01

    方便地接入Internet,对于发挥Ad hoc网络的潜能至关重要.首先说明了Ad hoc网络接入Internet面临的问题,然后介绍了一种基于连接共享机制使Ad hoc网络接入Internet的网络配置,接着详细阐述了连接共享的过程和相关机制,并对连接共享协议的开销进行了分析.

  13. An Adaptive Gateway Discovery Algorithm to support QoS When Providing Internet Access to Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Mari Carmen Domingo

    2007-04-01

    Full Text Available When a node in an ad hoc network wants Internet access, it needs to obtain information about the available gateways and it should select the most appropriate of them. In this work we propose a new gateway discovery scheme suitable for real-time applications that adjusts the frequency of gateway advertisements dynamically. This adjustment is related to the percentage of real-time sources that have quality of service problems because of excessive end-to-end delays. The optimal values for the configuration parameters (time interval and threshold of the proposed adaptive gateway discovery mechanism for the selected network conditions have been studied with the aid of simulations. The scalability of the proposed scheme with respect to mobility as well as the impact of best-effort traffic load have been analyzed. Simulation results indicate that the proposed scheme significantly improves the average end-to-end delay, jitter and packet delivery ratio of real-time flows; the routing overhead is also reduced and there is no starvation of best-effort traffic.

  14. 移动Ad Hoc网络MAC协议综述%A Survey of Medium Access Control Protocols for Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    安红章; 谢上明

    2006-01-01

    移动Ad Hoc网络(MANET)是移动节点自组织网络,由于特殊的应用环境成为现今研究的热点.文章对MANET物理信道的特点作了描述并对其MAC协议进行了归类和详细介绍,同时分析了各种协议的优缺点,最后对整个领域及未来的研究方向作了简要的总结和说明.

  15. Benefits for dominant red deer hinds under a competitive feeding system: food access behavior, diet and nutrient selection.

    Directory of Open Access Journals (Sweden)

    Francisco Ceacero

    Full Text Available Social dominance is widely known to facilitate access to food resources in many animal species such as deer. However, research has paid little attention to dominance in ad libitum access to food because it was thought not to result in any benefit for dominant individuals. In this study we assessed if, even under ad libitum conditions, social rank may allow dominant hinds to consume the preferred components of food. Forty-four red deer hinds (Cervus elaphus were allowed to consume ad libitum meal consisting of pellets of sunflower, lucerne and orange, and seeds of cereals, corn, cotton, and carob tree. The meal was placed only in one feeder, which reduced accessibility to a few individuals simultaneously. During seven days, feeding behavior (order of access, time to first feeding bout, total time spent feeding, and time per feeding bout were assessed during the first hour. The relative abundance of each meal component was assessed at times 0, 1 and 5 h, as well as its nutritional composition. Social rank was positively related to the amount of time spent feeding during the 1(st h (P = 0.048. Selection indices were positively correlated with energy (P = 0.018 during the 1(st h and P = 0.047 from 1(st to 5(th and fat (only during the 1(st h; P = 0.036, but also negatively with certain minerals. Thus, dominant hinds could select high energy meal components for longer time under an ad libitum but restricted food access setting. Selection indices showed a higher selectivity when food availability was higher (1(st hour respect to 1(st to 5(th. Finally, high and low ranking hinds had longer time per feeding bout than mid ones (P = 0.011, suggesting complex behavioral feeding tactics of low ranking social ungulates.

  16. Benefits for dominant red deer hinds under a competitive feeding system: food access behavior, diet and nutrient selection.

    Science.gov (United States)

    Ceacero, Francisco; García, Andrés J; Landete-Castillejos, Tomás; Bartošová, Jitka; Bartoš, Ludek; Gallego, Laureano

    2012-01-01

    Social dominance is widely known to facilitate access to food resources in many animal species such as deer. However, research has paid little attention to dominance in ad libitum access to food because it was thought not to result in any benefit for dominant individuals. In this study we assessed if, even under ad libitum conditions, social rank may allow dominant hinds to consume the preferred components of food. Forty-four red deer hinds (Cervus elaphus) were allowed to consume ad libitum meal consisting of pellets of sunflower, lucerne and orange, and seeds of cereals, corn, cotton, and carob tree. The meal was placed only in one feeder, which reduced accessibility to a few individuals simultaneously. During seven days, feeding behavior (order of access, time to first feeding bout, total time spent feeding, and time per feeding bout) were assessed during the first hour. The relative abundance of each meal component was assessed at times 0, 1 and 5 h, as well as its nutritional composition. Social rank was positively related to the amount of time spent feeding during the 1(st) h (P = 0.048). Selection indices were positively correlated with energy (P = 0.018 during the 1(st) h and P = 0.047 from 1(st) to 5(th)) and fat (only during the 1(st) h; P = 0.036), but also negatively with certain minerals. Thus, dominant hinds could select high energy meal components for longer time under an ad libitum but restricted food access setting. Selection indices showed a higher selectivity when food availability was higher (1(st) hour respect to 1(st) to 5(th)). Finally, high and low ranking hinds had longer time per feeding bout than mid ones (P = 0.011), suggesting complex behavioral feeding tactics of low ranking social ungulates.

  17. Achievable Rate Estimation of IEEE 802.11ad Visual Big-Data Uplink Access in Cloud-Enabled Surveillance Applications.

    Science.gov (United States)

    Kim, Joongheon; Kim, Jong-Kook

    2016-01-01

    This paper addresses the computation procedures for estimating the impact of interference in 60 GHz IEEE 802.11ad uplink access in order to construct visual big-data database from randomly deployed surveillance camera sensing devices. The acquired large-scale massive visual information from surveillance camera devices will be used for organizing big-data database, i.e., this estimation is essential for constructing centralized cloud-enabled surveillance database. This performance estimation study captures interference impacts on the target cloud access points from multiple interference components generated by the 60 GHz wireless transmissions from nearby surveillance camera devices to their associated cloud access points. With this uplink interference scenario, the interference impacts on the main wireless transmission from a target surveillance camera device to its associated target cloud access point with a number of settings are measured and estimated under the consideration of 60 GHz radiation characteristics and antenna radiation pattern models.

  18. IMPROVEMENT OF ACCESSION DISTINCTIVENESS AS AN ADDED VALUE TO THE GLOBAL WORTH OF THE YAM (DIOSCOREA SPP GENEBANK

    Directory of Open Access Journals (Sweden)

    Gezahegn GIRMA

    2012-09-01

    Full Text Available Misidentification of accessions is a common problem in genebanks. Along the years, mistakes accumulate and this is particularly true when dealing with a large number of accessions requiring annual regeneration. Human errors such as mislabeling or misreading and material mix up during planting or storage are the main causes for misidentification of accessions. The international collection of yam, maintained at IITA, has accumulated ‘non true to type’ accessions along the years. In the present study, 53 morphological descriptors were used to detect uniformity of individuals within accessions of the yam gene bank collection i.e. agro morphological mismatch between individual plants of the same accession. Based on a similarity matrix, individual pairs with less than 0.90 similarity coefficients, which varies in six descriptors and more, were considered as distinct and mismatched, whereas those that had similarity coefficients greater than or equal to 0.90 were considered as clones from the same parent. Overall, 20.60% of the total 3156 accessions were found not true to type i.e., misidentified individuals. The descriptive analysis shows that morphological traits like distance between lobes, upward folding of leaf along main vein, young stem color, old stem color, leaf shape, leaf density and plant vigor are the most discriminative descriptors for individual identification within accession. Some other traits were also found species specific and they may aid in distinguishing misidentifications between species.

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

    DEFF Research Database (Denmark)

    Hjorth, Mads Fiil; Sjödin, Anders Mikael; Dalskov, Stine-Mathilde

    2016-01-01

    simultaneously for seven 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.......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) mmHg, fat intake by 1.1 (0.2;2.0) 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). Conclusions: The susceptibility to increase abdominal adiposity and blood pressure when exposed to dietary changes can potentially be explained by too little sleep that results in increased caloric intake and reduced physical activity....

  20. Body Composition and Energy Expenditure Predict Ad-Libitum Food and Macronutrient Intake in Humans

    OpenAIRE

    Weise, Christopher M.; Hohenadel, Maximilian G.; Krakoff, Jonathan; Votruba, Susanne B.

    2013-01-01

    Background Obesity is the result of chronic positive energy balance. The mechanisms underlying the regulation of energy homeostasis and food intake are not understood. Despite large increases in fat mass (FM), recent evidence indicates that fat-free mass (FFM) rather than FM is positively associated with intake in humans. Methods In 184 humans (73F/111M; age 34.5±8.8y; % body fat [PFAT] 31.6±8.1%) we investigated the relationship of FFM index (FFMI kg*m2), FM index (FMI kg*m2;), and 24-hour e...

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

    Science.gov (United States)

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

    2015-03-15

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

  2. The effect of three different ad libitum diets for weight loss maintenance

    DEFF Research Database (Denmark)

    Due, Anette; Larsen, Thomas M; Mu, Huiling

    2015-01-01

    PURPOSE: To test the effect of three diets in their ability to sustain weight loss and improve type 2 diabetes (T2D) and cardiovascular disease (CVD) risk markers after 18-month intervention. METHODS: Following a ≥8 % weight loss, 131 healthy, overweight/obese (BMI ± SD 31.5 ± 2.6 kg/m(2)) men (n.......23 ± 0.11 in LF (P Weight regain or body composition did not differ between diets over 18 months. No effects on risk markers for T2D or CVD were found, with the exception of an improvement in the LDL/HDL ratio by the MUFA diet compared.......09) group. Weight regain in completers was not different between groups (mean ± SEM), MUFA 7.1 ± 2.1 % versus LF 5.6 ± 1.3 % versus CTR 7.2 ± 1.5 %, nor was body fat regain, MUFA 4.8 ± 1.0 % versus LF 4.7 ± 0.8 % versus CTR 5.7 ± 0.6 %. The MUFA group reduced LDL/HDL ratio by -0.47 ± 0.09 compared with -0...

  3. Increasing fruit and vegetable intake among male university students in an ad libitum buffet setting

    DEFF Research Database (Denmark)

    Kongsbak, Ida; Skov, Laurits Rohden; Køpke Nielsen, Brit;

    2016-01-01

    due to the complexity of determinants for food choices and more research is therefore needed. This study assessed the of a choice architectural intervention aimed at reducing energy density of meals consumed by male university students, by proportionally increasing their vegetable consumption.A single...... the two groups (-50.4 g p=.326). This emphasizes that the relative proportion of F&V/non-F&V changes as a result of the intervention.This study found convincing evidence for combining order of placement in a buffet and separating the fruits and vegetables, as a means to increase the quantity of self...

  4. Ad-Hoc Numbers Forming Provision and Policy: Round and Round of Universal Access in an Australian Preschool

    Science.gov (United States)

    Millei, Zsuzsa; Gallagher, Jannelle

    2017-01-01

    Australian early childhood education still labours with the achievement of universal access and the production of comprehensive and consistent data to underpin a national evidence base. In this article, we attend to the processes led by numbers whereby new practices of quantification, rationalization and reporting are introduced and mastered in a…

  5. Analysis of Multi-Channel and Slotted Random Multi-Access Protocol with Two-Dimensional Probability for Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ningyu; ZHAO Dongfeng; DING Hongwei

    2008-01-01

    A higher quality of service (QoS) is provided for ad hoc networks through a multi-channel and slotted random multi-access (MSRM) protocol with two-dimensional probability. For this protocol, the system time is slotted into a time slot with high channel utilization realized by the choice of two parameters p1 and p2, and the channel load equilibrium. The protocol analyzes the throughput of the MSRM protocol for a load equilibrium state and the throughput based on priority. Simulations agree with the theoretical analysis. The simulations also show that the slotted-time system is better than the continuous-time system.

  6. 移动自组网的访问控制技术研究%Research on Access Control Technology on Mobile Ad-hoc Networks

    Institute of Scientific and Technical Information of China (English)

    熊庭刚; 卢正鼎; 张家宏

    2011-01-01

    网络资源的共享与保护是移动自组网需要解决的关键问题之一.运用Voronoi图模型和quorum系统的思想,提出了一种移动自组网的动态路径quorum系统,设计了动态路径quorum的生成算法.基于移动自组网的动态路径quorum系统,提出了基于quorum系统的移动自组网的分布式访问控制机制,详细描述了节点的身份认证、网络资源的访问控制和权限管理协议.与传统的基于单个节点自身的访问控制机制相比,该访问控制机制具有较强的抗攻击能力和较高的可靠性,能够有效地提高移动自组网的资源共享与保护水平.%Resources share and protection are one of key problems needed to solve on mobile ad-hoc networks(MANET). A dynamic paths quorum system on MANET was proposed by making use of the model of voronoi diagram and the idea of quorum system. The construction algorithm of dynamic paths quorum was designed. Based on the dynamic paths quorum system on MANET, a distributed access control mechanism was given and the protocols, such as node authentication, network resources authorization and rights management, were described in detail Compared with traditional access control mechanism grounded on single node in MANET, the distributed access control mechanism grounded on more nodes, i. e. a quorum nodes, has higher availability and greater capability to withstand attack. It can improve the level of resources share and protection on MANET observably.

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

    Science.gov (United States)

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

    2007-03-01

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

  8. Preparing Precipitation Data Access, Value-added Services and Scientific Exploration Tools for the Integrated Multi-satellitE Retrievals for GPM (IMERG)

    Science.gov (United States)

    Ostrenga, D.; Liu, Z.; Kempler, S. J.; Vollmer, B.; Teng, W. L.

    2013-12-01

    The Precipitation Data and Information Services Center (PDISC) (http://disc.gsfc.nasa.gov/precipitation or google: NASA PDISC), located at the NASA Goddard Space Flight Center (GSFC) Earth Sciences (GES) Data and Information Services Center (DISC), is home of the Tropical Rainfall Measuring Mission (TRMM) data archive. For over 15 years, the GES DISC has served not only TRMM, but also other space-based, airborne-based, field campaign and ground-based precipitation data products to the precipitation community and other disciplinary communities as well. The TRMM Multi-Satellite Precipitation Analysis (TMPA) products are the most popular products in the TRMM product family in terms of data download and access through Mirador, the GES-DISC Interactive Online Visualization ANd aNalysis Infrastructure (Giovanni) and other services. The next generation of TMPA, the Integrated Multi-satellitE Retrievals for GPM (IMERG) to be released in 2014 after the launch of GPM, will be significantly improved in terms of spatial and temporal resolutions. To better serve the user community, we are preparing data services and samples are listed below. To enable scientific exploration of Earth science data products without going through complicated and often time consuming processes, such as data downloading, data processing, etc., the GES DISC has developed Giovanni in consultation with members of the user community, requesting quick search, subset, analysis and display capabilities for their specific data of interest. For example, the TRMM Online Visualization and Analysis System (TOVAS, http://disc2.nascom.nasa.gov/Giovanni/tovas/) has proven extremely popular, especially as additional datasets have been added upon request. Giovanni will continue to evolve to accommodate GPM data and the multi-sensor data inter-comparisons that will be sure to follow. Additional PDISC tool and service capabilities being adapted for GPM data include: An on-line PDISC Portal (includes user guide, etc

  9. Increasing fruit and vegetable intake among male university students in an ad libitum buffet setting

    DEFF Research Database (Denmark)

    Kongsbak, Ida; Skov, Laurits Rohden; Nielsen, Brit Køpke

    2016-01-01

    one-day lunch meal study was conducted in a FoodScape Laboratory where an Intelligent Buffet was used to register the exact weight of each meal component self-served by each participant. A convenience sample of 65 men was divided to a control group (n= 32) and an intervention group (n= 33). The choice...

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

    Science.gov (United States)

    Meule, Adrian; Hormes, Julia M

    2015-08-01

    The Food Cravings Questionnaires are the most commonly used instruments for the assessment of trait and state food craving. Chocolate is the most frequently craved food in Western societies. In the current studies, the Food Cravings Questionnaire-Trait-reduced (FCQ-T-r) and the Food Cravings Questionnaire-State (FCQ-S) were adapted to capture strong urges for chocolate. In study 1, students (n = 492; 81.3% female) completed chocolate versions of the FCQ-T-r and FCQ-S among other measures online. The FCQ-T-r (α = .94) comprised two subscales representing lack of control (α = .91) and thoughts about chocolate (α = .91). The FCQ-S (α = .87) comprised two subscales representing chocolate craving (α = .90) and hunger (α = .85). FCQ-T-r scores were significantly and positively correlated with self-reported frequency of consuming chocolate and with scores on the Attitudes to Chocolate Questionnaire, indicating good convergent validity. In study 2, students (n = 76; 73.7% female) underwent a chocolate exposure in the laboratory. FCQ-S scores increased during chocolate exposure and increases in momentary chocolate craving were significantly positively correlated with increases in salivary flow. Higher momentary chocolate craving was positively correlated with higher laboratory chocolate consumption. Exploratory analyses revealed that increases in salivary flow were only associated with increased chocolate consumption in participants scoring high, but not low on trait chocolate craving. The chocolate versions of the FCQ-T-r and FCQ-S represent reliable and valid self-report measures for the assessment of trait and state chocolate craving. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Bone Composition in Male and Female Göttingen Minipigs Fed Variously Restrictedly and near ad Libitum

    DEFF Research Database (Denmark)

    Bollen, P. J. A.; Lemmens, A. G.; Beynen, A. C.

    2006-01-01

    diet 2 was a high fat, low fibre diet. A higher level of feed intake led to a significant increase in the following parameters: body weight development, bone size (length and width of rib and femur), bone volume (rib), bone (rib) dry matter and ash content (mg), as well as bone density (femur...... development, bone volume, and dry matter and ash content of the rib (mg) as compared to males. Also bone mineral concentrations in the femur, expressed as calcium, phosphorus and magnesium in mg/cm3, were significantly higher in females as compared to males, as was the Ca:Pi ratio. Bone density measurements...

  12. Effects of different protein content and glycemic index of ad libitum diets on diabetes risk factors in overweight adults

    DEFF Research Database (Denmark)

    Goyenechea, Estibaliz; Holst, Claus; Saris, Wim H.M.

    2011-01-01

    Dpt. Physiology and Nutrition, University of Navarra, Pamplona, Spain (EG, JAM); Institute of Preventive Medicine, Centre for Health and Society, Copenhagen, Denmark (CH), Department of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, Maastricht, the N...

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

    NARCIS (Netherlands)

    Sjollema, Jelmer; Dijkstra, Rene J.B.; Abeln, Caroline; van der Mei, Henderina; Van Asseldonk, Dirk; Busscher, Hendrik

    2014-01-01

    Antimicrobial releasing biomaterial coatings have found application for instance in the fixation of orthopedic joint prostheses and central venous catheters. Most frequently, the release kinetics is such that antimicrobially-effective concentrations are only reached within the first days to weeks af

  14. Pen-mate directed behaviour in ad libitum fed pigs given different quantities and frequencies of straw

    DEFF Research Database (Denmark)

    Amdi, C.; Lahrmann, H.P.; Oxholm, L.C.

    2015-01-01

    Straw stimulates explorative behaviour and is therefore attractive to pigs. Further, it can be effective in reducing negative pen-mate directed behaviours. Under most commercial conditions, straw can only be used in limited amounts as it can be difficult to handle in most vacuum slurry systems...... and is expensive. In addition, straw needs to remain fresh in order to have a degree of novelty. The aim of this study was to investigate pen-mate directed behaviour in pigs given different straw treatments. Pigs were assigned to one of five treatments testing either quantity or frequency of chopped straw...

  15. Impact of weight loss and maintenance with ad libitum diets varying in protein and glycemic index content on metabolic syndrome

    DEFF Research Database (Denmark)

    Papadaki, Angeliki; Linardakis, Manolis; Plada, Maria

    2014-01-01

    We investigated the effects of weight loss and maintenance with diets that varied with regard to protein content and glycemic index (GI) on metabolic syndrome (MetSyn) status.......We investigated the effects of weight loss and maintenance with diets that varied with regard to protein content and glycemic index (GI) on metabolic syndrome (MetSyn) status....

  16. Diet-induced obesity in ad libitum-fed mice: food texture overrides the effect of macronutrient composition.

    Science.gov (United States)

    Desmarchelier, Charles; Ludwig, Tobias; Scheundel, Ronny; Rink, Nadine; Bader, Bernhard L; Klingenspor, Martin; Daniel, Hannelore

    2013-04-28

    Diet-induced obesity in mice can be achieved through the use of diets with different macronutrient compositions and textures. We aimed at determining the contribution of macronutrient composition to obesity development and associated pathophysiological changes in mice. C57BL/6N mice were offered a control, a high-fat or a Western-style diet, either as pellet (H for hard) or with identical composition in powder form (S for soft), resulting in C-S, C-H, HF-H, HF-S, W-H and W-S groups, respectively. Body fat distribution, expression levels of selected target genes in adipose tissues, clinical chemistry and hormone concentration in the blood, as well as liver TAG content were measured. The most striking finding was that all mice fed the different powder diets developed obesity with similar weight gain, whereas among the mice fed the pellet diets, only those given the HF and W diets became obese. This allowed us to separate diet-specific effects from obesity-mediated effects. Irrespective of the food texture, the W diet induced a more severe hepatosteatosis and higher activities of serum transaminases compared with the two other diets. Adipose tissue gene expression analysis revealed that leptin and adiponectin levels were not affected by the dietary composition per se, whereas uncoupling protein 1 and 11β-hydroxysteroid dehydrogenase type 1 levels were decreased by both dietary composition and changes in body weight. In conclusion, diets differing in macronutrient composition elicit specific pathophysiological changes, independently of changes in body weight. A diet high in both fat and sugars seems to be more deleterious for the liver than a HF diet.

  17. Facing temptation in the bar: counteracting the effects of self-control failure on young adults' ad libitum alcohol intake

    NARCIS (Netherlands)

    Otten, R.; Cladder-Micus, M.B.; Pouwels, J.L.; Hennig, M.; Schuurmans, A.T.; Hermans, R.C.J.

    2014-01-01

    Background and Aims The self-control strength model suggests that exertion of self-control leads to poorer subsequent self-control performance. Failure of self-control has been suggested as an important underlying mechanism of excessive drinking. This study tested the effects of self-control

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

    DEFF Research Database (Denmark)

    Damsgaard, Camilla Trab; Papadaki, Angeliki; Jensen, Signe Marie

    2013-01-01

    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 waist circumference (P = 0.004), blood pressure......, increased protein intake improved cardiovascular markers in high-risk children, particularly in those undergoing most intensive intervention....

  19. Comparison of 3 ad libitum diets for weight-loss maintenance, risk of cardiovascular disease, and diabetes

    DEFF Research Database (Denmark)

    Due, Anette Pia; Larsen, Thomas Meinert; Mu, Huiling

    2008-01-01

    The optimal dietary content and type of fat and carbohydrate for weight management has been debated for decades.......The optimal dietary content and type of fat and carbohydrate for weight management has been debated for decades....

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

    Science.gov (United States)

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

    2009-08-01

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

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

    OpenAIRE

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

    2015-01-01

    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...

  2. La presenza di riviste Open Access ad alto fattore d'impatto nell'ambito della Scienza, della Tecnologia, dell'Ingegneria e della Medicina (STEM

    Directory of Open Access Journals (Sweden)

    Annarita Barbaro

    2015-09-01

    Full Text Available Il presente studio ha lo scopo di definire a quali servizi sono aperte le riviste ad accesso aperto di alta qualità, per la pubblicazione; esaminando la loro distribuione nella varie discipline scientifiche, tra cui la distribuzione di alcune riviste che non prevedono spese di perfezionamento degli articoli. Lo studio si basa su un confronto sistematico tra le riviste incluse nel DOAJ e le riviste indicizzate sul Journal Citation Reports (JCR Science edition 2013, pubblicato da Thomson Reuters. Il fattore di impatto delle riviste ad accesso aperto è inferiore a quello di altre riviste, in quantità minima, ma significativa. Le riviste ad accesso aperto sono presenti nel quartile più in alto (in base al fattore di impatto di 85 su 176 (48,8% delle categorie esaminate. Non sono presenti riviste ad accesso aperto con un fattore di impatto solo in 16 categorie (9%.

  3. 移动Ad HOc网络中的公平按需多址接入协议%A Fair On-Demand Access Protocol for Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    刘凯; 李汉涛; 张军

    2006-01-01

    基于快速、有效竞争预约接入、无冲突轮询传输的思想和带冲突预防的冲突分解策略,本文提出了适于移动Ad Hoc网络的公平按需多址接入(FODA)协议.该协议在分群结构的基础上,利用公平冲突预防算法预约信道资源获得轮询服务,从而完全消除了载波侦听方式下多跳无线网络业务传输中的隐藏终端和暴露终端问题.另外,公平冲突预防算法解决了节点竞争接入时的冲突问题和不公平现象.最后,仿真结果表明,与带冲突避免的载波侦听多址接入(CSMA/CA)和轮询协议相比,FODA协议可以提供较高的信道吞吐量、较低的平均消息丢弃率和平均消息时延.

  4. Adding Ajax

    CERN Document Server

    Powers, Shelley

    2007-01-01

    Ajax can bring many advantages to an existing web application without forcing you to redo the whole thing. This book explains how you can add Ajax to enhance, rather than replace, the way your application works. For instance, if you have a traditional web application based on submitting a form to update a table, you can enhance it by adding the capability to update the table with changes to the form fields, without actually having to submit the form. That's just one example.Adding Ajax is for those of you more interested in extending existing applications than in creating Rich Internet Applica

  5. Hunger in pregnant sows: Effects of a fibrous diet and free access to straw

    DEFF Research Database (Denmark)

    Jensen, Margit Bak; Pedersen, Lene Juul; Theil, Peter Kappel

    2015-01-01

    of metabolites and hormones in pregnant sows. Ten groups of three pregnant sows were housed in pens with concrete floor where a limited amount of chopped straw (approx. 330 g/sow) was provided daily. In 5 of the 10 groups sows had free access to uncut straw in racks in addition to the chopped straw (Ad libitum...... periods. Furthermore, the sows’ feeding motivation was assessed during behavioural tests, and blood samples were draw via a jugular vein catheter, at 0700, 0900, 1200 and 1900 h in a balanced design. Feeding motivation was not affected by diet or straw. However, feeding motivation was highest 1 h before...... morning feeding indicated by a higher number of rewards earned during the entire test (P floor less frequently (P

  6. String Theory on AdS Spaces

    NARCIS (Netherlands)

    de Boer, J.

    2000-01-01

    In these notes we discuss various aspects of string theory in AdS spaces. We briefly review the formulation in terms of Green-Schwarz, NSR, and Berkovits variables, as well as the construction of exact conformal field theories with AdS backgrounds. Based on lectures given at the Kyoto YITP Workshop

  7. Online Ad Assignment with an Ad Exchange

    OpenAIRE

    Dvořák, Wolfgang; Henzinger, Monika

    2016-01-01

    Ad exchanges are becoming an increasingly popular way to sell advertisement slots on the internet. An ad exchange is basically a spot market for ad impressions. A publisher who has already signed contracts reserving advertisement impressions on his pages can choose between assigning a new ad impression for a new page view to a contracted advertiser or to sell it at an ad exchange. This leads to an online revenue maximization problem for the publisher. Given a new impression to sell decide whe...

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

    OpenAIRE

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

    2016-01-01

    (1) Background: The Paleolithic diet is popular in Australia, however, limited literature surrounds the dietary pattern. Our primary aim was to compare the Paleolithic diet with the Australian Guide to Healthy Eating (AGHE) in terms of anthropometric, metabolic and cardiovascular risk factors, with a secondary aim to examine the macro and micronutrient composition of both dietary patterns; (2) Methods: 39 healthy women (mean ± SD age 47 ± 13 years, BMI 27 ± 4 kg/m2) were randomised to either ...

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

    Science.gov (United States)

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

    2016-05-23

    (1) BACKGROUND: The Paleolithic diet is popular in Australia, however, limited literature surrounds the dietary pattern. Our primary aim was to compare the Paleolithic diet with the Australian Guide to Healthy Eating (AGHE) in terms of anthropometric, metabolic and cardiovascular risk factors, with a secondary aim to examine the macro and micronutrient composition of both dietary patterns; (2) METHODS: 39 healthy women (mean ± SD age 47 ± 13 years, BMI 27 ± 4 kg/m²) were randomised to either the Paleolithic (n = 22) or AGHE diet (n = 17) for four weeks. Three-day weighed food records, body composition and biochemistry data were collected pre and post intervention; (3) RESULTS: Significantly greater weight loss occurred in the Paleolithic group (-1.99 kg, 95% CI -2.9, -1.0), p Paleolithic group had lower intakes of carbohydrate (-14.63% of energy (E), 95% CI -19.5, -9.7), sodium (-1055 mg/day, 95% CI -1593, -518), calcium (-292 mg/day 95% CI -486.0, -99.0) and iodine (-47.9 μg/day, 95% CI -79.2, -16.5) and higher intakes of fat (9.39% of E, 95% CI 3.7, 15.1) and β-carotene (6777 μg/day 95% CI 2144, 11410) (all p Paleolithic diet induced greater changes in body composition over the short-term intervention, however, larger studies are recommended to assess the impact of the Paleolithic vs. AGHE diets on metabolic and cardiovascular risk factors in healthy populations.

  10. Serum concentrations of creatine kinase and of triglycerides during lactation in gilts bred older and in multiparous sows fed ad libitum

    Directory of Open Access Journals (Sweden)

    Nogueira R.H.G.

    2000-01-01

    Full Text Available The aim of this paper was to assess the possible variation in blood concentrations of creatine kinase (CK and triglycerides in gilts bred older in comparison with multiparous sows. Ten primiparous and ten Camborough multiparous sows from the fourth to seventh parities were used. Breeding age and weight of gilts averaged respectively 231 days and 149.5kg. All females were moved into individual farrowing crates and were managed under the same conditions. Blood samples were collected by puncturing the coccygeal artery on day 7 before expected farrowing, and on days 2, 7, 14, 21 of lactation and 2 days after weaning. No difference in triglycerides and CK serum concentrations between groups were observed. The CK levels were low before farrowing, increased substantially on days 2 and 7 and decreased toward the end of lactation. The concentrations of triglycerides were slightly high before the parturition, diminished on days 2, 7, 14 and 21 and increased after weaning.

  11. Comparison of 3 ad libitum diets for weight-loss maintenance, risk of cardiovascular disease, and diabetes: A 6-mo randomized, controlled trial

    DEFF Research Database (Denmark)

    Due, Anette; Larsen, Thomas M; Mu, Huiling

    2008-01-01

    a 6-mo controlled dietary intervention. DESIGN: Nondiabetic overweight or obese [mean +/- SD body mass index (in kg/m(2)): 31.5 +/- 2.6] men (n = 55) and women (n = 76) aged 28.2 +/- 4.8 y were randomly assigned to a diet providing a moderate amount of fat (35-45% of energy) and >20% of fat...... as monounsaturated fatty acids (MUFA diet; n = 54), to a low-fat (20-30% of energy) diet (LF diet; n = 51), or to a control diet (35% of energy as fat; n = 26). Protein constituted 10-20% of energy in all 3 diets. All foods were provided free of charge from a purpose-built supermarket. RESULTS: More subjects dropped.......6%) groups than in the control group (2.6 +/- 0.5%) (P fasting insulin decreased by 2.6 +/- 3.5 pmol/L, the homeostasis model assessment of insulin resistance by 0.17 +/- 0.13, and the ratio of LDL to HDL by 0.33 +/- 0.13; in the LF group, these variables increased by 4.3 +/- 3...

  12. Weight loss maintenance in overweight subjects on ad libitum diets with high or low protein content and glycemic index

    DEFF Research Database (Denmark)

    Aller, E E J G; Larsen, Thomas Meinert; Holst, Claus

    2014-01-01

    Background:A high dietary protein (P) content and low glycemic index (GI) have been suggested to be beneficial for weight management, but long-term studies are scarce.Objective:The DIOGENES randomized clinical trial investigated the effect of P and GI on weight loss maintenance in overweight....../high GI (HP/HGI), low P/low GI (LP/LGI), low P/high GI (LP/HGI) and a control diet. During the first 6 months foods were provided for free through a shop system, during the whole 12-month period subjects received guidance by a dietician. Primary outcome variable was the change in body weight over the 12...

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

    Directory of Open Access Journals (Sweden)

    Angela Genoni

    2016-05-01

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

  14. Efecto de la intensidad de la música en el rendimiento durante la realización de ejercicio Ad Libitum en cicloergómetro.

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Aburto Corona

    2013-10-01

    Full Text Available El propósito de este estudio fue determinar si la Frecuencia Cardíaca (FC, el Esfuerzo Percibido (EP y el Trabajo Voluntario Realizado (TVR están influenciados por la intensidad de la música. En este estudio se comprobó si la teoría de ciertos entrenadores de gimnasios es cierta, “a mayor intensidad de sonido (decibeles, el rendimiento físico es mejor”. Aunque de cierta forma “esa intensidad” puede llegar a ser cómplice para una lesión auditiva que puede ser temporal o permanente a corto, mediano o  largo plazo. Se analizó la influencia que tiene la música respecto al rendimiento físico de las personas que se ejercitan en un cicloergómetro en determinadas condiciones musicales: Música del agrado de los sujetos de entre 100 y 130 pulsos por minuto (ppm a 75 (M75 o 95 (M95 decibeles (dB o una condición sin música (SM. No se encontraron diferencias estadísticamente significativas entre las tres condiciones en la FC (182.8±15.80, 186.5±13.41, 186±13.38 ppm el EP (6.75±2.20, 7.3±2, 7.5±1.9 u.a. ni en el Trabajo Voluntario Realizado (106.8±11.98, 113.2±12.30, 109.6±20.30 KJ para SM, M75 y M95 respectivamente. No hubo interacción significativa entre el tratamiento (SM, M75 y M95 y la medición (T1 y T2 (p>0.05, más sí hubo diferencias significativas entre mediciones, lo cual significa que independientemente de la intensidad, los sujetos realizaron más trabajo en la segunda mitad que en la primera.

  15. The Effects of Caloric Density of the Food on Running Endurance and General Condition of Rats and Hamsters Restricted in Food Intake or Fed Ad Libitum

    Science.gov (United States)

    1975-08-01

    lipolysis . Am. J. Cardiol. 20: 525-530 (1967). 7. Pruett, E.D.R.: Glucose and insulin during prolonged work stress in men living on different diets...in obese young men of car^’-’-’-irate level of reduction diet. Am. J. Cli.:. Nutr. 2H. 29r-296 (1971). 20. Pande, S.V. and M.C. Blanchaer

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

    DEFF Research Database (Denmark)

    Kristensen, M.; Jensen, M.G.; Riboldi, G.

    2010-01-01

    Wholegrain foods have received much attention in recent years, and have been proposed to play a role in energy regulation through lowering of postprandial glycemia and appetite. This randomized crossover single meal study in 16 Young adults Was Conducted to test the effect of iso-caloric meals...

  17. Effects on markers of inflammation and endothelial cell function of three ad libitum diets differing in type and amount of fat and carbohydrate

    DEFF Research Database (Denmark)

    Bladbjerg, Else-Marie; Larsen, Thomas Meinert; Due, Anette Pia

    2011-01-01

    Diet is important for the prevention of CVD, and diets high in MUFA might be more cardioprotective than low-fat diets. We hypothesise that inflammation and endothelial cell function will be improved most favourably by a high-MUFA diet compared with a low-fat diet. This was tested in a parallel...... randomised intervention trial on overweight individuals (aged 28·2 (sd 4·6) years) assigned to a diet moderate in the amount of fat (35-45% of energy; >20% of fat as MUFA; MUFA diet, n 39), a low-fat (20-30% of energy) diet (LF diet, n 43) or a control diet (35 % of energy as fat, n 24) for 6 months after...... weight loss. Protein constituted 10-20 % of energy in all diets. Food was provided free of charge. Fasting blood samples were collected before and after the intervention and analysed for C-reactive protein (CRP), IL-6, intercellular adhesion molecule, von Willebrand factor (vWF) and tissue factor pathway...

  18. Insulin-like growth factor I and glucagon-like peptide-2 responses to fasting followed by controlled or ad libitum refeeding in rats

    DEFF Research Database (Denmark)

    Nelson, David W; Murali, Sangita G; Liu, Xiaowen

    2008-01-01

    Luminal nutrients stimulate structural and functional regeneration in the intestine through mechanisms thought to involve insulin-like growth factor I (IGF-I) and glucagon-like peptide-2 (GLP-2). We investigated the relationship between IGF-I and GLP-2 responses and mucosal growth in rats fasted ...

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

    NARCIS (Netherlands)

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

    2012-01-01

    Food intake and a food’s expected satiating effect initially rely on sensory attributes. People will learn about the food’s satiating capacity by exposure. We investigated whether repeated consumption changed the expected satiety effects and intake of iso-energetic liquid and semi-solid foods. In a

  20. Effects of intraduodenal infusion of L-tryptophan on ad libitum eating, antropyloroduodenal motility, glycemia, insulinemia, and gut peptide secretion in healthy men.

    Science.gov (United States)

    Steinert, Robert E; Luscombe-Marsh, Natalie D; Little, Tanya J; Standfield, Scott; Otto, Bärbel; Horowitz, Michael; Feinle-Bisset, Christine

    2014-09-01

    Changes in gut motor and hormonal function contribute to the eating-inhibitory and glucose-lowering effects of protein. The effect of amino acids, the digestive products of protein, on gastrointestinal function, eating, and glycemia has not been investigated comprehensively. We tested the hypothesis that L-tryptophan (L-Trp) stimulates gastrointestinal motor and hormonal functions, inhibits eating, and modulates glycemia. Design, Settings, Participants, and Intervention: Ten healthy, normal-weight men were studied in randomized, double-blind fashion, each receiving a 90-minute intraduodenal infusion of L-Trp at 0.075 (total 6.75 kcal) or 0.15 (total 13.5 kcal) kcal/min or saline (control). Antropyloroduodenal motility, plasma ghrelin, cholecystokinin, glucagon-like peptide-1, peptide tyrosine tyrosine, insulin, glucagon, blood glucose, and appetite perceptions were measured. Food intake was quantified from a buffet meal after the infusion. Intraduodenal L-Trp suppressed antral pressures (P eating-inhibitory effect.

  1. Genetic parameters and effect of selection for body weight in lines of mink (Neovion vison) on ad libitum and restricted feeding

    DEFF Research Database (Denmark)

    Nielsen, Vivi Hunnicke; Møller, Steen Henrik; Hansen, Bente Krog;

    2012-01-01

    .60 in females in the FF-, AL-, and RF-line). The results indicate that selection on AL feeding increased appetite and thereby improved feed conversion ratio while selection on RF improved feed utilization. Furthermore, the results suggest that selection for August weight produces lean mink while selection...

  2. Lipid metabolism and mitochondrial energy production are key pathways involved in adipose tissue of cows transitioning from feed restriction to ad libitum diets

    Science.gov (United States)

    Feed costs account for over 70% of the annual expenditures in cow/calf production. The majority of the nutrients are used to support the cow’s maintenance requirements and substrate cycling has been identified as one of the major contributors toward this type of energy expenditure. The objective of ...

  3. Long-term effects on haemostatic variables of three ad libitum diets differing in type and amount of fat and carbohydrate

    DEFF Research Database (Denmark)

    Bladbjerg, Else-Marie; Larsen, Thomas Meinert; Due, Anette Pia

    2010-01-01

    Diet is important in the prevention of CVD, and it has been suggested that a diet high in MUFA is more cardioprotective than a low-fat diet. We hypothesised that the thrombotic risk profile is improved most favourably by a high-MUFA diet compared with a low-fat diet. This was tested in a parallel...... randomised intervention trial on overweight individuals (aged 28·2 (sd 4·6) years) randomly assigned to a diet providing a moderate amount of fat (35-45 % of energy; >20 % of fat as MUFA) (MUFA diet; n 39), to a low-fat (LF; 20-30 % of energy) diet (n 43), or to a control diet (35 % of energy as fat; n 24......) for 6 months after a weight loss of about 10 %. Protein constituted 10-20 % of energy in all three diets. All foods were provided free of charge from a purpose-built supermarket. Fasting blood samples were collected before and after intervention and analysed for factor VII coagulant activity (FVII...

  4. Segmented Strings in $AdS_3$

    CERN Document Server

    Callebaut, Nele; Samberg, Andreas; Toldo, Chiara

    2015-01-01

    We study segmented strings in flat space and in $AdS_3$. In flat space, these well known classical motions describe strings which at any instant of time are piecewise linear. In $AdS_3$, the worldsheet is composed of faces each of which is a region bounded by null geodesics in an $AdS_2$ subspace of $AdS_3$. The time evolution can be described by specifying the null geodesic motion of kinks in the string at which two segments are joined. The outcome of collisions of kinks on the worldsheet can be worked out essentially using considerations of causality. We study several examples of closed segmented strings in $AdS_3$ and find an unexpected quasi-periodic behavior. We also work out a WKB analysis of quantum states of yo-yo strings in $AdS_3$ and find a logarithmic term reminiscent of the logarithmic twist of string states on the leading Regge trajectory.

  5. Polarised black holes in AdS

    Science.gov (United States)

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

    2016-06-01

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

  6. Polarised Black Holes in AdS

    CERN Document Server

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

    2016-01-01

    We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global $AdS_{4}$ with conformal boundary $S^{2}\\times\\mathbb{R}_{t}$. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic $AdS$ behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an $AdS$ soliton that includes the full backreaction of the electric field on the $AdS$ geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both $AdS$ soliton and black hole phases. The corresponding phase diagram generalizes the Hawkin...

  7. Constructing Lifshitz solutions from AdS

    CERN Document Server

    Cassani, Davide

    2011-01-01

    Under general assumptions, we show that a gravitational theory in d+1 dimensions admitting an AdS solution can be reduced to a d-dimensional theory containing a Lifshitz solution with dynamical exponent z=2. Working in a d=4, N=2 supergravity setup, we prove that if the AdS background is N=2 supersymmetric, then the Lifshitz geometry preserves 1/4 of the supercharges, and we construct the corresponding Killing spinors. We illustrate these results in examples from supersymmetric consistent truncations of type IIB supergravity, enhancing the class of known 4-dimensional Lifshitz solutions of string theory. As a byproduct, we find a new AdS4 x S1 x T(1,1) solution of type IIB.

  8. Ad Hoc网络%Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    王海涛

    2005-01-01

    首先介绍了Ad Hoc网络的基本概念、技术特点以及关键技术等,然后较为全面地归纳了Ad Hoc网络的典型应用,最后讨论了Ad Hoc网络的发展趋势和有待解决的问题.

  9. AdS orbifolds and Penrose limits

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-12-09

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

  10. Feeding and growth of Japanese quail (Coturnix c. japonica) chicks with unpredictable food access

    NARCIS (Netherlands)

    Boon, P; Visser, GH; Daan, S

    1999-01-01

    We investigated the effect of unpredictable feeding times on feeding activity and body mass gain in fast growing Japanese quail (Coturnix c. japonica) from 7 to 31 d of age. Quail chicks were subjected to a long day length (18L:6D) with ad libitum food during (1) 17.5 h of the light period, starting

  11. Superradiant instability in AdS

    CERN Document Server

    Ganchev, Bogdan

    2016-01-01

    The phenomenon of superradiance in the context of asymptotically global AdS spacetimes is investigated with particular accent on its effect on the stability of the systems under consideration. To this end, the concept of an asymptotically AdS spacetime is explained, together with its implications on the boundary conditions at $\\mathcal{I}$, as well as the Newman-Penrose-Teukolsky formalism, whereby the Teukolsky master equation in a most general form for Kerr-AdS is given. Furthermore, work done in the cases of RN-AdS and Kerr-AdS is laid out in a concise manner, putting emphasis on the important steps taken in determining the endpoint of the superradiant instability in the two configurations. For the former this turns out to be a black hole with reduced charge and a static charged scalar condensate around it, whereas for the latter two of the more probable outcomes are presented, both of which imply a violation of one of the cosmic censorships.

  12. Lorentzian AdS, Wormholes and Holography

    CERN Document Server

    Arias, Raul E; Silva, Guillermo A

    2011-01-01

    We investigate the structure of two point functions for the QFT dual to an asymptotically Lorentzian AdS-wormhole. The bulk geometry is a solution of 5-dimensional second order Einstein Gauss Bonnet gravity and causally connects two asymptotically AdS space times. We revisit the GKPW prescription for computing two-point correlation functions for dual QFT operators O in Lorentzian signature and we propose to express the bulk fields in terms of the independent boundary values phi_0^\\pm at each of the two asymptotic AdS regions, along the way we exhibit how the ambiguity of normalizable modes in the bulk, related to initial and final states, show up in the computations. The independent boundary values are interpreted as sources for dual operators O^\\pm and we argue that, apart from the possibility of entanglement, there exists a coupling between the degrees of freedom leaving at each boundary. The AdS_(1+1) geometry is also discussed in view of its similar boundary structure. Based on the analysis, we propose a ...

  13. Introducing ADS 2.0

    Science.gov (United States)

    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.

  14. Boson Stars in AdS

    CERN Document Server

    Buchel, Alex; Lehner, Luis

    2013-01-01

    We construct boson stars in global Anti de Sitter (AdS) space and study their stability. Linear perturbation results suggest that the ground state along with the first three excited state boson stars are stable. We evolve some of these solutions and study their nonlinear stability in light of recent work \\cite{Bizon:2011gg} arguing that a weakly turbulent instability drives scalar perturbations of AdS to black hole formation. However evolutions suggest that boson stars are nonlinearly stable and immune to the instability for sufficiently small perturbation. Furthermore, these studies find other families of initial data which similarly avoid the instability for sufficiently weak parameters. Heuristically, we argue that initial data families with widely distributed mass-energy distort the spacetime sufficiently to oppose the coherent amplification favored by the instability. From the dual CFT perspective our findings suggest that there exist families of rather generic initial conditions in strongly coupled CFT ...

  15. AdS solutions through transgression

    Energy Technology Data Exchange (ETDEWEB)

    Donos, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Gauntlett, J.P. [Imperial College, London (United Kingdom). Blackett Lab.]|[Imperial College, London (United Kingdom). The Institute for Mathematical Sciences; Kim, Nakwoo [Kyung Hee Univ., Seoul (Korea). Dept. of Physics and Research Inst. of Basic Science

    2008-07-15

    We present new classes of explicit supersymmetric AdS{sub 3} solutions of type IIB supergravity with non-vanishing five-form flux and AdS{sub 2} solutions of D=11 supergravity with electric four-form flux. The former are dual to two-dimensional SCFTs with (0,2) supersymmetry and the latter to supersymmetric quantum mechanics with two supercharges. We also investigate more general classes of AdS{sub 3} solutions of type IIB supergravity and AdS{sub 2} solutions of D=11 supergravity which in addition have non-vanishing three-form flux and magnetic four-form flux, respectively. The construction of these more general solutions makes essential use of the Chern-Simons or ''transgression'' terms in the Bianchi identity or the equation of motion of the field strengths in the supergravity theories. We construct infinite new classes of explicit examples and for some of the type IIB solutions determine the central charge of the dual SCFTs. The type IIB solutions with non-vanishing three-form flux that we construct include a two-torus, and after two T-dualities and an S-duality, we obtain new AdS3 solutions with only the NS fields being non-trivial. (orig.)

  16. Refined Holographic Entanglement Entropy for the AdS Solitons and AdS black Holes

    CERN Document Server

    Ishihara, Masafumi; Ning, Bo

    2012-01-01

    We consider the refinement of the holographic entanglement entropy on a disk region for the holographic dual theories to the AdS solitons and AdS black holes, including the corrected ones by the Gauss-Bonnet term. The AdS soliton is dual to a gapped system with an IR fixed-point. The refinement is obtained by extracting the UV-independent piece of the holographic entanglement entropy. We then study the renormalization group (RG) flow of the refinement by tuning the linear size of the chosen disk region. Our main results are (i) the RG flow of the refinement decreases monotonically for most of the cases; (ii) there is no topological entanglement entropy for AdS$_5$ soliton even with Gauss-Bonnet correction; (iii) for the AdS black holes, the refinement obeys the volume law at IR regime, and the transition between UV and IR regimes is a smooth crossover; however, the crossover will turn into phase transition by the Gauss-Bonnet correction; (iv) for the AdS solitons, there are discontinuous phase transitions bet...

  17. Predicting AD conversion

    DEFF Research Database (Denmark)

    Liu, Yawu; Mattila, Jussi; Ruiz, Miguel �ngel Mu�oz

    2013-01-01

    To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool) and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA) on MRI...

  18. An AdS Crunch in Supergravity

    Science.gov (United States)

    Hertog, Thomas

    2004-12-01

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

  19. Adding more value to added-value

    DEFF Research Database (Denmark)

    Marian, Livia

    regulation. The results of a qualitative concept test reveal positive attitudes towards the proposed production process. The discussions about fewer standards being sufficient or about options “in-between” conventional and organic standards indicate that the difference in production processes is noticed, yet...... it is probably valued less than expected. The added attributes need to be thoroughly considered when developing and marketing “organic plus” products, as their effect on other product characteristics (e.g. high prices) can detract from their added value....

  20. Differences in bingeing behavior and cocaine reward following intermittent access to sucrose, glucose or fructose solutions.

    Science.gov (United States)

    Rorabaugh, J M; Stratford, J M; Zahniser, N R

    2015-08-20

    Daily intermittent access to sugar solutions results in intense bouts of sugar intake (i.e. bingeing) in rats. Bingeing on sucrose, a disaccharide of glucose and fructose, has been associated with a "primed" mesolimbic dopamine (DA) pathway. Recent studies suggest glucose and fructose engage brain reward and energy-sensing mechanisms in opposing ways and may drive sucrose intake through unique neuronal circuits. Here, we examined in male Sprague-Dawley rats whether or not (1) intermittent access to isocaloric solutions of sucrose, glucose or fructose results in distinctive sugar-bingeing profiles and (2) previous sugar bingeing alters cocaine locomotor activation and/or reward, as determined by conditioned place preference (CPP). To encourage bingeing, rats were given 24-h access to water and 12-h-intermittent access to chow plus an intermittent bottle that contained water (control) or 8% solutions of sucrose, glucose or fructose for 9days, followed by ad libitum chow diet and a 10-day cocaine (15mg/kg; i.p.) CPP paradigm. By day 4 of the sugar-bingeing diet, sugar bingeing in the fructose group surpassed the glucose group, with the sucrose group being intermediate. All three sugar groups had similar chow and water intake throughout the diet. In contrast, controls exhibited chow bingeing by day 5 without altering water intake. Similar magnitudes of cocaine CPP were observed in rats with a history of sucrose, fructose or chow (control) bingeing. Notably, the glucose-bingeing rats did not demonstrate a significant cocaine CPP despite showing similar cocaine-induced locomotor activity as the other diet groups. Overall, these results show that fructose and glucose, the monosaccharide components of sucrose, produce divergent degrees of bingeing and cocaine reward.

  1. Probing crunching AdS cosmologies

    Science.gov (United States)

    Kumar, S. Prem; Vaganov, Vladislav

    2016-02-01

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

  2. The political attack ad

    Directory of Open Access Journals (Sweden)

    Palma Peña-Jiménez, Ph.D.

    2011-01-01

    Full Text Available During election campaigns the political spot has a clear objective: to win votes. This message is communicated to the electorate through television and Internet, and usually presents a negative approach, which includes a direct critical message against the opponent, rather than an exposition of proposals. This article is focused on the analysis of the campaign attack video ad purposely created to encourage the disapproval of the political opponent among voters. These ads focus on discrediting the opponent, many times, through the transmission of ad hominem messages, instead of disseminating the potential of the political party and the virtues and manifesto of its candidate. The article reviews the development of the attack ad since its first appearance, which in Spain dates back to 1996, when the famous Doberman ad was broadcast, and examines the most memorable campaign attack ads.

  3. Probing crunching AdS cosmologies

    CERN Document Server

    Kumar, S Prem

    2015-01-01

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of N=8 supergravity on AdS_4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor a_{max} . Radial geodesics connecting antipodal points necessarily have de Sitter energy E \\leq a_{max}, while geodesics with E > a_{max} terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outw...

  4. Holography of AdS vacuum bubbles

    Energy Technology Data Exchange (ETDEWEB)

    Barbon, J.L.F. [Instituto de Fisica Teorica IFT UAM/CSIC, Cantoblanco, Madrid 28049 (Spain); Rabinovici, E. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel)

    2011-07-15

    We consider the fate of AdS vacua connected by tunneling events. A precise holographic dual of thin-walled Coleman-de Luccia bounces is proposed in terms of Fubini instantons in an unstable CFT. This proposal is backed by several qualitative and quantitative checks, including the precise calculation of the instanton action appearing in evaluating the decay rate. Big crunches manifest themselves as time dependent processes which reach the boundary of field space in a finite time. The infinite energy difference involved is identified on the boundary and highlights the ill-defined nature of the bulk setup. We propose a qualitative scenario in which the crunch is resolved by stabilizing the CFT, so that all attempts at crunching always end up shielded from the boundary by the formation of black hole horizons. In all these well defined bulk processes the configurations have the same asymptotics and are finite energy excitations.

  5. Twistor methods for AdS$_5$

    CERN Document Server

    Adamo, Tim; Williams, Jack

    2016-01-01

    We consider the application of twistor theory to five-dimensional anti-de Sitter space. The twistor space of AdS$_5$ is the same as the ambitwistor space of the four-dimensional conformal boundary; the geometry of this correspondence is reviewed for both the bulk and boundary. A Penrose transform allows us to describe free bulk fields, with or without mass, in terms of data on twistor space. Explicit representatives for the bulk-to-boundary propagators of scalars and spinors are constructed, along with twistor action functionals for the free theories. Evaluating these twistor actions on bulk-to-boundary propagators is shown to produce the correct two-point functions.

  6. AdS2 holographic dictionary

    Science.gov (United States)

    Cvetič, Mirjam; Papadimitriou, Ioannis

    2016-12-01

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

  7. Flexible access control for dynamic collaborative environments

    NARCIS (Netherlands)

    Dekker, Mari Antonius Cornelis

    2009-01-01

    Access control is used in computer systems to control access to confidential data. In this thesis we focus on access control for dynamic collaborative environments where multiple users and systems access and exchange data in an ad hoc manner. In such environments it is difficult to protect confident

  8. Skil problemerne ad

    DEFF Research Database (Denmark)

    Kaspersen, Peter

    2007-01-01

    På grundlag af evalueringer og forskning i gymnasiereformen 2005 foreslås det at skille problemerne ad i forskellige niveauer. Herved kan der arbejdes med niveaudelte løsninger.......På grundlag af evalueringer og forskning i gymnasiereformen 2005 foreslås det at skille problemerne ad i forskellige niveauer. Herved kan der arbejdes med niveaudelte løsninger....

  9. Probing crunching AdS cosmologies

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. Prem; Vaganov, Vladislav [Department of Physics, Swansea University,Singleton Park, Swansea SA2 8PP (United Kingdom)

    2016-02-03

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of N=8 supergravity on AdS{sub 4}, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor ã{sub max}. Radial geodesics connecting antipodal points necessarily have de Sitter energy E≲ã{sub max}, while geodesics with E>ã{sub max} terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved “outward” in the Penrose diagram for the deformed AdS backgrounds, and thus geodesic limits of the antipodal correlators do not directly probe the crunch. Beyond the geodesic limit, we point out that the scalar wave equation, analytically continued into the FRW patch, has a potential which is singular at the crunch along with complex WKB turning points in the vicinity of the FRW crunch. We then argue that the frequency space Green’s function has a branch point determined by ã{sub max} which corresponds to the lowest quasinormal frequency.

  10. Comparison of caloric intake and weight outcomes of an ad lib feeding regimen for preterm infants in two nurseries.

    Science.gov (United States)

    Pridham, K F; Kosorok, M R; Greer, F; Kayata, S; Bhattacharya, A; Grunwald, P

    2001-09-01

    Effects on caloric intake and weight gain of an ad libitum (ad lib) feeding regimen for preterm infants may be specific to a special care nursery. To explore across two nurseries the similarity of effect on caloric intake and weight gain of an ad lib feeding regimen compared with a prescribed regimen and the similarity of effect of caloric intake on weight gain. All infants participating in the multi-site randomized clinical trial (RCT) of the ad lib feeding regimen were lib. After accounting for caloric intake, the ad lib regimen did not affect weight gain. The time-by-regimen interaction effect on caloric intake was significant in both nurseries. Caloric intake for infants fed ad lib increased significantly over 5 days. Despite differences between nurseries in infant characteristics and in protocol implementation, the feeding regimen effect was consistent for caloric intake and weight gain. Further support was found for the development of infant self-regulatory capacity.

  11. Mobile ad hoc networking

    CERN Document Server

    John Wiley & Sons

    2004-01-01

    "Assimilating the most up-to-date information on research and development activities in this rapidly growing area, Mobile Ad Hoc Networking covers physical, data link, network, and transport layers, as well as application, security, simulation, and power management issues in sensor, local area, personal, and mobile ad hoc networks. Each of the book's sixteen chapters has been written by a top expert and discusses in-depth the most important topics in the field. Mobile Ad Hoc Networking is an excellent reference and guide for professionals seeking an in-depth examination of topics that also provides a comprehensive overview of the current state-of-the-art."--Jacket.

  12. Reference Linking with DOIs: A Case Study [and] The Santa Fe Convention of the Open Archives Initiative [and] The UPS Prototype: An Experiment End-User Service across E-Print Archives [and] The Costs of Print, Fiche, and Digital Access: The Early Canadiana Online Project [and] Ad*Access: Seeking Copyright Permissions for a Digital Age.

    Science.gov (United States)

    Atkins, Helen; Lyons, Catherine; Ratner, Howard; Risher, Carol; Shillum, Chris; Sidman, David; Stevens, Andrew; Van de Sompel, Herbert; Lagoze, Carl; Van de Sompel, Herbert; Krichel, Thomas; Nelson, Michael L.; Hochstenbach, Patrick; Lyapunov, Victor M.; Maly, Kurt; Zubair, Mohammad; Kholief, Mohamed; Liu, Xiaoming; O'Connell, Heath; Kingma, Bruce R.; Pritcher, Lynn

    2000-01-01

    Includes five articles that discuss publishers' metadata hyperlinks with Digital Object Identifiers (DOIs) on the Internet; the Santa Fe Convention of the Open Archives initiative (Oai) that promotes author self-archiving; the Universal Preprint Service; costs of digital, microfiche, and print access; and an online database of old print…

  13. Antiproton-Decelerator (AD)

    CERN Multimedia

    Laurent Guiraud

    1998-01-01

    When the Low-Energy Antiproton Ring (LEAR) was stopped in 1996, because of its costly operation, a cheaper way of continuing low-energy antiproton physics was sought. The Antiproton-Collector (AC), added in 1987 to the Antiproton Accumulator (AA) to provide a tenfold intensity increase, was converted into the Antiproton-Decelerator (AD). Antiprotons from the target at 3.5 GeV/c are decelerated to 100 MeV/c, and fast-ejected to the experiments. Major changes were necessary. Above all, the conversion from a constant-field machine to one with a magnetic cycle, modulating the field by an impressive factor 35. New systems for stochastic and electron cooling had to be added. Beam diagnostics at an intensity of only 2E7 antiprotons was a challenge. In 2000, the AD began delivery of antiprotons to the experiments.

  14. Value Adding Management

    DEFF Research Database (Denmark)

    Jensen, Per Anker; Katchamart, Akarapong

    2011-01-01

    Purpose: To investigate how Facilities Management (FM) can add value and develop a management concept that can assist facilities managers in implementing value adding strategies and practices. Theory: The study is based on the management model for FM included in the European FM standards, recent...... theories on added value of FM and real estate and the related concept of Value Management from building projects. The study is related to the EuroFM research group on The Added Value of FM. Design/methodology/approach: The study outlines a preliminary theoretical based management concept, which...... is investigated, tested and discussed based on a case study of an international corporation. Findings: The study shows that the management model for FM creates a relevant starting point but also that stakeholder and relationship management is an essential aspect of Value Adding Management. The case study confirms...

  15. AdS_3: the NHEK generation

    CERN Document Server

    Bena, Iosif; Puhm, Andrea

    2015-01-01

    It was argued in arXiv:1203.4227 that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically-AdS_3 x S^3/Z_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.

  16. Multilevel security model for ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    Wang Changda; Ju Shiguang

    2008-01-01

    Modern battlefield doctrine is based on mobility, flexibility, and rapid response to changing situations.As is well known, mobile ad hoc network systems are among the best utilities for battlefield activity. Although much research has been done on secure routing, security issues have largely been ignored in applying mobile ad hoc network theory to computer technology. An ad hoc network is usually assumed to be homogeneous, which is an irrational assumption for armies. It is clear that soldiers, commanders, and commanders-in-chief should have different security levels and computation powers as they have access to asymmetric resources. Imitating basic military rank levels in battlefield situations, how multilevel security can be introduced into ad hoc networks is indicated, thereby controlling restricted classified information flows among nodes that have different security levels.

  17. Open access

    NARCIS (Netherlands)

    Valkenburg, P.M.

    2015-01-01

    Open access week Van 19 tot en met 25 oktober 2015 vond wereldwijd de Open Access Week plaats. Tijdens deze week werden er over de hele wereld evenementen georganiseerd waar open access een rol speelt. Ook in Nederland zijn er diverse symposia, workshops en debatten georganiseerd zoals het debat in

  18. Dynamic ad hoc networks

    CERN Document Server

    Rashvand, Habib

    2013-01-01

    Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s

  19. Ad hoc networks telecommunications and game theory

    CERN Document Server

    Benslama, Malek; Batatia, Hadj

    2015-01-01

    Random SALOHA and CSMA protocols that are used to access MAC in ad hoc networks are very small compared to the multiple and spontaneous use of the transmission channel. So they have low immunity to the problems of packet collisions. Indeed, the transmission time is the critical factor in the operation of such networks. The simulations demonstrate the positive impact of erasure codes on the throughput of the transmission in ad hoc networks. However, the network still suffers from the intermittency and volatility of its efficiency throughout its operation, and it switches quickly to the satura

  20. Investigation of a role for ghrelin signaling in binge-like feeding in mice under limited access to high-fat diet.

    Science.gov (United States)

    King, S J; Rodrigues, T; Watts, A; Murray, E; Wilson, A; Abizaid, A

    2016-04-05

    Binge eating is defined by the consumption of an excessive amount of food in a short time, reflecting a form of hedonic eating that is not necessarily motivated by caloric need. Foods consumed during a binge are also often high in fat and/or sugar. Ghrelin, signaling centrally via the growth-hormone secretagogue receptor (GHSR), stimulates growth hormone release and appetite. GHSR signaling also enhances the rewarding value of palatable foods and increases the motivation for such foods. As ghrelin interacts directly with dopaminergic reward circuitry, shown to be involved in binge eating, the current studies explored the role of GHSR signaling in a limited access model of binge eating in mice. In this model, mice received either intermittent (INT) or daily (DAILY) access to a nutritionally complete high-fat diet (HFD) for 2h late in the light cycle, alongside 24-h ad libitum chow. In CD-1 mice, 2-h exposure to HFD generated substantial binge-like intake of HFD, as well as a binge-compensate pattern of 24-h daily intake. INT and daily groups did not differ in 2-h HFD consumption, while INT mice maintained stable intake of chow despite access to HFD. GHSR knock-out (KO) and wild-type (WT) mice both binged during HFD access, and exhibited the same binge-compensate pattern. INT GHSR KO mice did not binge as much as WT, while DAILY KO and WT were comparable. Overall, GHSR KO mice consumed fewer calories from HFD, regardless of access condition. GHSR KO mice also had reduced activation of the nucleus accumbens shell, but not core, following HFD consumption. These data support the ability of INT HFD in mice to induce a binge-compensate pattern of intake that emulates select components of binge eating in humans. There also appears to be a role for GHSR signaling in driving HFD consumption under these conditions, potentially via mediation of reward-related circuitry.

  1. adolesce t reproductive health services i jimma city: accessibility ad ...

    African Journals Online (AJOL)

    user

    . 2.09. 0.0040. Occupational status. Student. Others category. 2.09. 2.14. 0.3277 ... Pharmacy. 128. 11.8. Traditional healers. 22. 2.0. Others. 44. 4.1. Reason for not using RHS. Don't need now ..... and preferences: Consultation for reproductive.

  2. Assured Resource Sharing in Ad-Hoc Collaboration

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Gail-Joon [Arizona State Univ., Tempe, AZ (United States)

    2015-12-19

    The project seeks an innovative framework to enable users to access and selectively share resources in distributed environments, enhancing the scalability of information sharing. We have investigated secure sharing & assurance approaches for ad-hoc collaboration, focused on Grids, Clouds, and ad-hoc network environments.

  3. D-branes in Lorentzian AdS(3)

    CERN Document Server

    Israel, D

    2005-01-01

    We study the exact construction of D-branes in Lorentzian AdS(3). We start by defining a family of conformal field theories that gives a natural Euclidean version of the SL(2,R) CFT and does not correspond to H(3)+, the analytic continuation of AdS(3). We argue that one can recuperate the exact CFT results of Lorentzian AdS(3), upon an analytic continuation in the moduli space of these conformal field theories. Then we construct exact boundary states for various symmetric and symmetry-breaking D-branes in AdS(3).

  4. Localization on $AdS_2\\times S^1$

    CERN Document Server

    David, Justin R; Gupta, Rajesh Kumar; Narain, Kumar

    2016-01-01

    Conformal symmetry relates the metric on $AdS_2 \\times S^{1}$ to that of $S^3$. This implies that under a suitable choice of boundary conditions for fields on $AdS_2$ the partition function of conformal field theories on these spaces must agree which makes $AdS_2 \\times S^{1}$ a good testing ground to study localization on non-compact spaces. We study supersymmetry on $AdS_2\\times S^1$ and determine the localizing Lagrangian for ${\\cal N}=2$ supersymmetric Chern-Simons theory on $AdS_2\\times S^1$. We evaluate the partition function of ${\\cal N}=2$ supersymmetric Chern-Simons theory on $AdS_2 \\times S^1$ using localization, where the radius of $S^1$ is $q$ times that of $AdS_2$. With boundary conditions on $AdS_2\\times S^1$ which ensure that all the physical fields are normalizable and lie in the space of square integrable wave functions in $AdS_2$, the result for the partition function precisely agrees with that of the theory on the $q$-fold covering of $S^3$.

  5. Intermittent access to a nutritionally complete high-fat diet attenuates alcohol drinking in rats.

    Science.gov (United States)

    Sirohi, Sunil; Van Cleef, Arriel; Davis, Jon F

    2017-02-01

    Binge eating disorder and alcohol use disorder (AUD) frequently co-occur in the presence of other psychiatric conditions. Data suggest that binge eating engages similar behavioral and neurochemical processes common to AUD, which might contribute to the etiology or maintenance of alcoholism. However, it is unclear how binge feeding behavior and alcohol intake interact to promote initiation or maintenance of AUD. We investigated the impact of binge-like feeding on alcohol intake and anxiety-like behavior in male Long Evans rats. Rats received chow (controls) or extended intermittent access (24h twice a week; Int-HFD) to a nutritionally complete high-fat diet for six weeks. Standard rodent chow was available ad-libitum to all groups and food intake was measured. Following HFD exposure, 20.0% ethanol, 2.0% sucrose intake and endocrine peptide levels were evaluated. Anxiety-like behavior was measured using a light-dark (LD) box apparatus. Rats in the Int-HFD group displayed a binge-like pattern of feeding (alternations between caloric overconsumption and voluntary caloric restriction). Surprisingly, alcohol intake was significantly attenuated in the Int-HFD group whereas sugar consumption was unaffected. Plasma acyl-ghrelin levels were significantly elevated in the Int-HFD group, whereas glucagon-like peptide-1 levels did not change. Moreover, rats in the Int-HFD group spent more time in the light side of the LD box compared to controls, indicating that binge-like feeding induced anxiolytic effects. Collectively, these data suggest that intermittent access to HFD attenuates alcohol intake through reducing anxiety-like behavior, a process potentially controlled by elevated plasma ghrelin levels.

  6. Ads in Indonesia

    Directory of Open Access Journals (Sweden)

    Wulan Roro Retno

    2017-01-01

    Full Text Available Cosmetics industry created the beauty myth for women through advertising. A cosmetic ad in Indonesia has spread a new concept of white skin: East Asia beauty myth. The white concept of Asia white skin basically derived from colonial legacy. The purpose of the research was analyzing the beauty myth in Indonesia ads using postcolonial perspective. The principal result brought the discourse analysis and postcolonial perspective a new insight in communication research. Particularly on media and cultural studies. Major conclusions showed that the beauty myth since the Dutch colonial period never been change. The main concept is always in colonialism’s idea: “white is better”. The West is better than the East.

  7. Adding linear orders

    CERN Document Server

    Shelah, Saharon

    2011-01-01

    We address the following question: Can we expand an NIP theory by adding a linear order such that the expansion is still NIP? Easily, if acl(A)=A for all A, then this is true. Otherwise, we give counterexamples. More precisely, there is a totally categorical theory for which every expansion by a linear order has IP. There is also an \\omega-stable NDOP theory for which every expansion by a linear order interprets bounded arithmetic.

  8. Introduction to AdS/CFT correspondence

    CERN Document Server

    Nastase, Horatiu

    2015-01-01

    Providing a pedagogical introduction to the rapidly developing field of AdS/CFT correspondence, this is one of the first texts to provide an accessible introduction to all the necessary concepts needed to engage with the methods, tools and applications of AdS/CFT. Without assuming anything beyond an introductory course in quantum field theory, it begins by guiding the reader through the basic concepts of field theory and gauge theory, general relativity, supersymmetry, supergravity, string theory and conformal field theory, before moving on to give a clear and rigorous account of AdS/CFT correspondence. The final section discusses the more specialised applications, including QCD, quark-gluon plasma and condensed matter. This book is self-contained and learner-focused, featuring numerous exercises and examples. It is essential reading for both students and researchers across the fields of particle, nuclear and condensed matter physics.

  9. AdS 3-manifolds and Higgs bundles

    DEFF Research Database (Denmark)

    Alessandrini, Daniele; Li, Qiongling

    2015-01-01

    In this paper we investigate the relationships between closed AdS 3-manifolds and Higgs bundles. We have a new way to construct AdS structures that allows us to see many of their properties explicitly, for example we can recover the very recent formula by Tholozan for the volumes. We also find...

  10. Pathologies in Lovelock AdS Black Branes and AdS/CFT

    CERN Document Server

    Takahashi, Tomohiro

    2011-01-01

    We study the pathologies in AdS black branes in Lovelock theory. More precisely, we examine the conditions that AdS black branes have the naked singularity, the ghost instability and the dynamical instability. From the point of view of the AdS/CFT correspondence, the pathologies in AdS black branes indicate the pathologies in the corresponding CFT. Hence, we need to be careful when we apply AdS/CFT in Lovelock theory to various phenomena such as the shear viscosity to entropy ratio in strongly coupled quantum filed theory.

  11. Access Denied

    Science.gov (United States)

    Villano, Matt

    2008-01-01

    Building access control (BAC)--a catchall phrase to describe the systems that control access to facilities across campus--has traditionally been handled with remarkably low-tech solutions: (1) manual locks; (2) electronic locks; and (3) ID cards with magnetic strips. Recent improvements have included smart cards and keyless solutions that make use…

  12. Open Access

    Science.gov (United States)

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder…

  13. Open Access

    Science.gov (United States)

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder…

  14. The effect of Ad

    Institute of Scientific and Technical Information of China (English)

    李小艳

    2010-01-01

    There is the trend that now people appreciate those who are slim and regard slim even thin people beautiful. The thinner a person is, the more beautiful. Women, born to pursuit beauty, try various means to follow the trend. We all watch TV, and find a lot of advertisements on diet. The effect of them is tremendous. We all know the fact that it is not at all the better mouse trap will catch mouse. The sales methods are more important. If an advertisement is very interesting and seemingly effective, people will be lured by the ad and then try some of the products.

  15. Management job ads

    DEFF Research Database (Denmark)

    2014-01-01

    The article asks whether it is not the responsibility of corporations to address the issue of women being underrepresented in Danish management jobs. In other words, it is argued that corporations should be encouraged to engage more actively in the recruitment of both men and women for management...... that this agreement reflects a high degree of conservatism in the system where men enjoy a considerable advantage and where procedures that ensure male dominance are perpetuated even in the linguistic and discursive construction of job ads....

  16. Value-Added Exchange Rates

    OpenAIRE

    Rudolfs Bems; Robert C. Johnson

    2012-01-01

    This paper updates the conceptual foundations for measuring real effective exchange rates (REERs) to allow for vertical specialization in trade. We derive a value-added REER describing how demand for the value added that a country produces changes as the price of its value added changes relative to competitors. We then compute this index for 42 countries from 1970-2009 using trade measured in value added terms and GDP deflators. There are substantial differences between value-added and conven...

  17. An $xp$ model on $AdS_2$ spacetime

    CERN Document Server

    Molina-Vilaplana, Javier

    2013-01-01

    In this paper we formulate the $xp$ model on the AdS$_2$ spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, equal in magnitude, given by a harmonic oscillator with a zero point energy parameterized by the AdS radius, measured in units of a fundamental length of the model. We also construct the generators of the isometry group SO(2,1) of the AdS$_2$ spacetime, and discuss the relation with conformal quantum mechanics.

  18. Wireless Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Hong-Chuan Yang

    2007-01-01

    Full Text Available We study the energy-efficient configuration of multihop paths with automatic repeat request (ARQ mechanism in wireless ad hoc networks. We adopt a cross-layer design approach and take both the quality of each radio hop and the battery capacity of each transmitting node into consideration. Under certain constraints on the maximum tolerable transmission delay and the required packet delivery ratio, we solve optimization problems to jointly schedule the transmitting power of each transmitting node and the retransmission limit over each hop. Numerical results demonstrate that the path configuration methods can either significantly reduce the average energy consumption per packet delivery or considerably extend the average lifetime of the multihop route.

  19. Dressing phases of AdS3/CFT2

    CERN Document Server

    Borsato, Riccardo; Sfondrini, Alessandro; Stefanski, Bogdan; Torrielli, Alessandro

    2013-01-01

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

  20. Dressing phases of AdS3/CFT2

    Science.gov (United States)

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

    2013-09-01

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

  1. Quantum Field Theory and Unification in AdS5

    CERN Document Server

    Randall, Lisa; Randall, Lisa; Schwartz, Matthew D.

    2001-01-01

    We consider gauge bosons in the bulk of AdS5 in a two-brane theory that addresses the hierarchy problem. We show such a theory can be consistent with gauge coupling unification at a high scale. We discuss subtleties in this calculation and show how to regulate consistently in a bounded AdS5 background. Our regularization is guided by the holographic dual of the calculation.

  2. Chaos and hydrodynamics near AdS$_2$

    CERN Document Server

    Jensen, Kristan

    2016-01-01

    We revisit AdS$_2$ holography with the Sachdev-Ye-Kitaev models in mind. Our main result is to rewrite a generic theory of gravity near an AdS$_2$ throat as a novel hydrodynamics coupled to the correlation functions of a conformal quantum mechanics. This gives a prescription for the computation of $n$-point functions in the dual quantum mechanics. We thereby find that the dual is maximally chaotic.

  3. Supersymmetry of AdS and flat IIB backgrounds

    Science.gov (United States)

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

    2015-02-01

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

  4. Accessible Knowledge - Knowledge on Accessibility

    DEFF Research Database (Denmark)

    Kirkeby, Inge Mette

    2015-01-01

    Although serious efforts are made internationally and nationally, it is a slow process to make our physical environment accessible. In the actual design process, architects play a major role. But what kinds of knowledge, including research-based knowledge, do practicing architects make use of when...... designing accessible environments? The answer to the question is crucially important since it affects how knowledge is distributed and how accessibility can be ensured. In order to get first-hand knowledge about the design process and the sources from which they gain knowledge, 11 qualitative interviews...... were conducted with architects with experience of designing for accessibility. The analysis draws on two theoretical distinctions. The first is research-based knowledge versus knowledge used by architects. The second is context-independent knowledge versus context-dependent knowledge. The practitioners...

  5. ad hoc networks

    Directory of Open Access Journals (Sweden)

    Blanca Alicia Correa

    2007-01-01

    Full Text Available Los métodos de agrupamiento permiten que las MANET (redes móviles ad hoc presenten un mejor desempeño en cuanto a la rapidez de conexión, el enrutamiento y el manejo de la topología. En este trabajo se presenta una revisión sobre las técnicas de agrupamiento para MANET. Se introducen algunos temas preliminares que forman la base para el desarrollo de los algoritmos de agrupamiento, tales como: la topología de la red, el enrutamiento, la teoría de grafos y los algoritmos de movilidad. Adicionalmente, se describen algunas de las técnicas de agrupamiento más conocidas como Lowest-ID heuristic, Highest degree heuristic, DMAC (distributed mobility-adaptive clustering, WCA (weighted clustering algorithm, entre otros. El propósito central es ilustrar los conceptos principales respecto a las técnicas de agrupamiento en MANET.

  6. Action growth for AdS black holes

    Science.gov (United States)

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

    2016-09-01

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

  7. Comunicazione e Open Access

    Directory of Open Access Journals (Sweden)

    Orazio Maria Valastro

    2005-06-01

    Full Text Available Il potenziale editoriale della rivista, sebbene compia appena il suo terzo anno di attività, è considerevole: basti pensare che la scelta fondante una parte del progetto editoriale, la pubblicazione di testi integrali, accessibili liberamente e gratuitamente su formato html, ha permesso l’accrescersi costante della consultazione delle pagine web pubblicate su internet e del numero dei visitatori che hanno avuto accesso agli articoli diffusi per ogni numero trimestrale. Condividendo e promuovendo i principi dell’Open-Access, il libero accesso al patrimonio culturale e scientifico, partecipando ad una comunicazione scientifica che favorisca una democratizzazione della conoscenza, si è inoltre indotto un valore aggiunto allo strumento editoriale: la valorizzazione della produzione scientifica e degli stessi contributi degli autori, insieme all’ampia divulgazione dei contenuti, liberamente accessibili da qualsiasi luogo del mondo tramite una connessione ad internet.

  8. AdS_5 Black Holes with Fermionic Hair

    CERN Document Server

    Burrington, B A; Sabra, W A; Burrington, Benjamin A.; Liu, James T.

    2004-01-01

    The study of new BPS objects in AdS_5 has led to a deeper understanding of AdS/CFT. To help complete this picture, and to fully explore the consequences of the supersymmetry algebra, it is also important to obtain new solutions with bulk fermions turned on. In this paper we construct superpartners of the 1/2 BPS black hole in AdS_5 using a natural set of fermion zero modes. We demonstrate that these superpartners, carrying fermionic hair, have conserved charges differing from the original bosonic counterpart. To do so, we find the R-charge and dipole moment of the new system, as well as the mass and angular momentum, defined through the boundary stress tensor. The complete set of superpartners fits nicely into a chiral representation of AdS_5 supersymmetry, and the spinning solutions have the expected gyromagnetic ratio, g=1.

  9. Complexity Growth for AdS Black Holes

    CERN Document Server

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

    2016-01-01

    We further investigate the Complexity-Action (CA) duality conjecture for stationary anti de-Sitter (AdS) black holes and derive some exact results for the growth rate of action within Wheeler-DeWitt (WDW) patch at late time approximation, which is dual to the growth rate of quantum complexity of holographic state. Based on the results from the general $D$-dimensional Reissner-Nordstr\\"{o}m (RN)-AdS black hole, rotating/charged Ba\\~{n}ados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a new complexity bound but leave unchanged the conjecture that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.

  10. Open access

    CERN Document Server

    Suber, Peter

    2012-01-01

    The Internet lets us share perfect copies of our work with a worldwide audience at virtually no cost. We take advantage of this revolutionary opportunity when we make our work "open access": digital, online, free of charge, and free of most copyright and licensing restrictions. Open access is made possible by the Internet and copyright-holder consent, and many authors, musicians, filmmakers, and other creators who depend on royalties are understandably unwilling to give their consent. But for 350 years, scholars have written peer-reviewed journal articles for impact, not for money, and are free to consent to open access without losing revenue. In this concise introduction, Peter Suber tells us what open access is and isn't, how it benefits authors and readers of research, how we pay for it, how it avoids copyright problems, how it has moved from the periphery to the mainstream, and what its future may hold. Distilling a decade of Suber's influential writing and thinking about open access, this is the indispe...

  11. Constructing the AdS dual of a Fermi liquid: AdS Black holes with Dirac hair

    CERN Document Server

    \\vCubrović, Mihailo; Schalm, Koenraad

    2010-01-01

    We provide new 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 spatially averaged 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 $\\ome_F$, 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 probability density of the fermion field directly, we show that an AdS Reissner-Nordstr\\"{o}m black hole in 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 confirm that the solution with non-zero AdS fermion-profil...

  12. Access French

    CERN Document Server

    Grosz, Bernard

    2014-01-01

    Access is the major new language series designed with the needs of today's generation of students firmly in mind. Whether learning for leisure or business purposes or working towards a curriculum qualification, Access French is specially designed for adults of all ages and gives students a thorough grounding in all the skills required to understand, speak, read and write contemporary French from scratch. The coursebook consists of 10 units covering different topic areas, each of which includes Language Focus panels explaining the structures covered and a comprehensive glossary. Learning tips

  13. Metabolic Effects of Access to Sucrose Drink in Female Rats and Transmission of Some Effects to Their Offspring.

    Directory of Open Access Journals (Sweden)

    Michael D Kendig

    Full Text Available The aims of this study were, first, to examine the metabolic consequences for female rats of having unrestricted access to 10% sucrose solution and, second, to test for effects of this dietary intervention on their offspring. In Stage 1 females were mated following a 4-week period in which one group was given the sucrose in addition to their normal chow and a control group was given chow and water only. Sucrose was removed at parturition and the pups monitored until weaning. Despite the development of glucose intolerance in sucrose-fed mothers, no effects were detected on litter size or pup weights. In Stage 2 voluntary activity of offspring was assessed over postnatal days (PND 51-60 and their glucose tolerance measured at PND89-94. Again no effect of maternal diet was detected. Only male offspring were used in Stage 3, which began when they were 13 weeks old. Four groups were given 10% sucrose solution for 48 days in a 2 x 2 design, in which one factor was maternal diet and the other was whether they were given 2-h access to an activity wheel on alternate days. Higher fasting glucose levels were found in offspring of sugar-fed mothers. Exercise increased insulin sensitivity in these rats but not in offspring of control mothers. Behavioural measures of memory in Stage 3 did not reveal any effects of maternal diet or exercise. Overall, this study suggested that, while providing 10% sucrose solution ad-libitum was sufficient to impair maternal metabolism, the impact of this dietary manipulation on offspring may be revealed only when the offspring's diet is similarly manipulated.

  14. Global geometric properties of AdS space and the AdS/CFT correspondence

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Poisson kernels and relations between them for a massive scalar field in a unit ball Bn with Hua's metric and conformal flat metric are obtained by describing the Bn as a submanifold of an (n+1)-dimensional embedding space. Global geometric properties of the AdS space are discussed. We show that the(n+1)-dimensional AdS space AdSn+1 is isomorphic to RP1×Bn and boundary of the AdS is isomorphic to RP1×Sn-1. Bulk-boundary propagator and the AdS/CFT like correspondence are demonstrated based on these global geometric properties of the RP1×Bn.

  15. Different views of AEGIS / AD-6 Experiment (AD facility) AD-6

    CERN Multimedia

    Maximilien Brice

    2012-01-01

    Different views of AEGIS / AD-6 Experiment (AD facility) in July of 2012. The visible parts are the positron accumulator (blue structures on top of of the antiproton extraction line) and the 5T magnet which traps the antiprotons.

  16. AdS-Carroll Branes

    CERN Document Server

    Clark, T E

    2016-01-01

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

  17. Improved Functionality and Curation Support in the ADS

    Science.gov (United States)

    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.

  18. Hemodialysis access - self care

    Science.gov (United States)

    Kidney failure - chronic-hemodialysis access; Renal failure - chronic-hemodialysis access; Chronic renal insufficiency - hemodialysis access; Chronic kidney failure - hemodialysis access; Chronic renal failure - ...

  19. Entanglement entropy for free scalar fields in AdS

    CERN Document Server

    Sugishita, Sotaro

    2016-01-01

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

  20. Microstates at the boundary of AdS

    CERN Document Server

    Mathur, Samir D

    2011-01-01

    The bound states of the D1D5 brane system have a known gravitational description: flat asymptotics, an anti-de Sitter region, and a 'cap' ending the AdS region. We construct perturbations that correspond to the action of chiral algebra generators on Ramond ground states of D1D5 branes. Abstract arguments in the literature suggest that the perturbation should be pure gauge in the AdS region; our perturbation indeed has this structure, with the nontrivial deformation of the geometry occurring at the 'neck' between the AdS region and asymptotic infinity. This 'non-gauge' deformation is needed to provide the nonzero energy and momentum carried by the perturbation. We also suggest implications this structure may have for the majority of microstates which live at the cap.

  1. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    CERN Document Server

    Evnin, Oleg

    2016-01-01

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

  2. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium); Jai-akson, Puttarak [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand)

    2016-04-11

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

  3. Asymptotically AdS spacetimes with a timelike Kasner singularity

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Jie [Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel)

    2016-07-21

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

  4. Asymptotically AdS spacetimes with a timelike Kasner singularity

    Science.gov (United States)

    Ren, Jie

    2016-07-01

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

  5. Revisiting the thermodynamic relations in AdS /CMT models

    Science.gov (United States)

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

    2017-03-01

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

  6. Long-term effects on haemostatic variables of three ad libitum diets differing in type and amount of fat and carbohydrate: a 6-month randomised study in obese individuals

    DEFF Research Database (Denmark)

    Bladbjerg, Else-Marie; Larsen, Thomas M; Due, Anette

    2010-01-01

    ) for 6 months after a weight loss of about 10 %. Protein constituted 10-20 % of energy in all three diets. All foods were provided free of charge from a purpose-built supermarket. Fasting blood samples were collected before and after intervention and analysed for factor VII coagulant activity (FVII...

  7. 拴系饲养与自由采食对西门塔尔青年母牛超排效果的影响%Effect of Chained and Ad libitum Feeding on Superovulation of Simmental Heifers

    Institute of Scientific and Technical Information of China (English)

    李强; 牛志宏; 刘水涛; 张建军; 肖锐; 张光伟; 张健

    2012-01-01

    In 2009 and 2010, the two different feeding styles were used in Simmental heifers. After 102 Simmental heifers were superovulated, the results in two groups were compared. The results showed that in 2009 and 2010, the average recovery eggs and transferable embryo yield were 15.04 vs 13.65 and 8.51 vs 6.93, respectively. The embryo development rate in two groups was different. In conclusion under inadequate nutrition in the long term, the growth and development in Simmental heifers was affected, and their fertility, superovulation response and transferable embryo yield are decreased.%本文分析比较了2009和2010年两种不同饲养管理方式对102头西门塔尔青年母牛超排效果的影响。结果表明,2009年拴系饲养的供体牛超排效果明显好于2010年自由采食的供体牛,平均回收卵和有效胚胎分别为15.04枚、13.65枚,8.51枚、6.93枚。2009年的有效胚胎率(56.58%)也高于2010年(50.73%)。从胚胎发育阶段的比例来看,2010年供体牛的扩张囊胚和囊胚比例比2009年低,而未受精和退化胚胎比例较高。结果显示,青年母牛长期处于营养摄入量不足的情况下,不仅影响体成熟,还会降低母牛的繁殖机能和超排效果以及有效胚胎数。

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

    Science.gov (United States)

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

    2010-12-01

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

  9. Mapping AdS to dS and back

    CERN Document Server

    Di Dato, Adriana

    2014-01-01

    We derive a map between Einstein spaces of positive and negative curvature. Starting from a space of positive curvature with some dimensions compactified on a sphere and analytically continuing the number of compact dimensions, we obtain a space of negative curvature with a compact hyperbolic subspace, and vice versa. Prime examples of such spaces are de Sitter and Anti-de Sitter space, as well as black hole spacetimes with (A)dS asymptotics and perturbed versions thereof, which play an important role in holography. This map extends work done by Caldarelli et.al., who map asymptotically AdS spaces to Ricci-flat ones. A remarkable result is that the boundary of asymptotically AdS spaces is mapped to a brane in the bulk of de Sitter, and perturbations near the AdS boundary are sourced by a stress tensor confined to this brane. We also calculate the Brown-York stress tensor for the perturbed AdS metric, which turns out to be the negative of the stress tensor on the de Sitter brane.

  10. An $xp$ model on $AdS_2$ spacetime

    OpenAIRE

    2012-01-01

    In this paper we formulate the $xp$ model on the AdS$_2$ spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, whose absolute values are given by a harmonic oscillator spectrum, which in turn coincides with that of a massive Dirac fermion in AdS$_2$. We extend this result to generic $xp$ models which are shown to be equivalent to a massive Dirac fermion on spacetimes whose metric depend of the $xp$ Hamiltonian. Finally, we construct the generators of t...

  11. AdS5 magnetized solutions in minimal gauged supergravity

    Directory of Open Access Journals (Sweden)

    Jose Luis Blázquez-Salcedo

    2017-08-01

    Full Text Available We construct a generalization of the AdS charged rotating black holes with two equal magnitude angular momenta in five-dimensional minimal gauged supergravity. In addition to the mass, electric charge and angular momentum, the new solutions possess an extra-parameter associated with a non-zero magnitude of the magnetic potential at infinity. In contrast with the known cases, these new black holes possess a non-trivial zero-horizon size limit which describes a one parameter family of spinning charged solitons. All configurations reported in this work approach asymptotically an AdS5 spacetime in global coordinates and are free of pathologies.

  12. Diffusion and Chaos from near AdS$_2$ horizons

    CERN Document Server

    Blake, Mike

    2016-01-01

    We calculate the thermal diffusivity $D = \\kappa/c_{\\rho}$ and butterfly velocity $v_B$ in holographic models that flow to AdS$_2 \\times R^{d}$ 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 $D = v_B^2/(2 \\pi T)$.

  13. Intermittent access to a sucrose solution impairs metabolism in obesity-prone but not obesity-resistant mice.

    Science.gov (United States)

    Soto, Marion; Chaumontet, Catherine; Mauduit, Charles-David; Fromentin, Gilles; Palme, Rupert; Tomé, Daniel; Even, Patrick

    2016-02-01

    Consumption of sugar-sweetened beverages is associated with overweight and obesity. In this study, we hypothesized that obesity-prone (OP) mice fed a high-fat high-sucrose diet (HFHS) are more sensitive to consumption of sucrose-sweetened water (SSW) than obesity-resistant (OR) mice. After 3weeks of ad libitum access to the HFHS diet (7.5h/day), 180 male mice were classified as either OP (upper quartile of body weight gain, 5.2±0.1g, n=45) or OR (lower quartile, 3.2±0.1g, n=45). OP and OR mice were subsequently divided into 3 subgroups that had access to HFHS (7.5h/day) for 16weeks, supplemented with: i) water (OP/water and OR/water); ii) water and SSW (12.6% w/v), available for 2h/day randomly when access to HFHS was available and for 5 randomly-chosen days/week (OP/SSW and OR/SSW); or iii) water and SSW for 8weeks, then only water for 8weeks (OP/SSW-water and OR/SSW-water). OR/SSW mice decreased their food intake compared to OR/water mice, while OP/SSW mice exhibited an increase in food and total energy intake compared to OP/water mice. OP/SSW mice also gained more body weight and fat mass than OP/water mice, showed an increase in liver triglycerides and developed insulin resistance. These effects were fully reversed in OP/SSW-water mice. In the gut, OR/SSW mice, but not OP/SSW mice, had an increase GLP-1 and CCK response to a liquid meal compared to mice drinking only water. OP/SSW mice had a decreased expression of melanocortin receptor 4 in the hypothalamus and increased expression of delta opioid receptor in the nucleus accumbens compared to OP/water mice when fasted that could explain the hyperphagia in these mice. When access to the sucrose solution was removed for 8weeks, OP mice had increased dopaminergic and opioidergic response to a sucrose solution. Thus, intermittent access to a sucrose solution in mice fed a HFHS diet induces changes in the gut and brain signaling, leading to increased energy intake and adverse metabolic consequences only in mice

  14. Penrose inequality for asymptotically AdS spaces

    Energy Technology Data Exchange (ETDEWEB)

    Itkin, Igor [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Oz, Yaron, E-mail: yaronoz@post.tau.ac.il [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel)

    2012-02-28

    In general relativity, the Penrose inequality relates the mass and the entropy associated with a gravitational background. If the inequality is violated by an initial Cauchy data, it suggests a creation of a naked singularity, thus providing means to consider the cosmic censorship hypothesis. We propose a general form of Penrose inequality for asymptotically locally AdS spaces.

  15. Internet Advertising. Google AdWords versus Facebook Ads

    Directory of Open Access Journals (Sweden)

    Paul PAŞCU

    2014-05-01

    Full Text Available This article describes how to use the applications for Internet advertising, Google AdWords and Facebook Ads. Our attempt is to present the advantages and disadvantages of each of them, the costs and benefits, a useful aspect for companies that plan to start advertising campaigns on the Internet.

  16. Predicting AD conversion: comparison between prodromal AD guidelines and computer assisted PredictAD tool.

    Directory of Open Access Journals (Sweden)

    Yawu Liu

    Full Text Available To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA on MRI and CSF biomarkers.Altogether 391 MCI cases (158 AD converters were selected from the ADNI cohort. All the cases had baseline cognitive tests, MRI and/or CSF levels of Aβ1-42 and Tau. Using baseline data, the status of MCI patients (AD or MCI three years later was predicted using current diagnostic research guidelines and the PredictAD software tool designed for supporting clinical diagnostics. The data used were 1 clinical criteria for episodic memory loss of the hippocampal type, 2 visual MTA, 3 positive CSF markers, 4 their combinations, and 5 when the PredictAD tool was applied, automatically computed MRI measures were used instead of the visual MTA results. The accuracies of diagnosis were evaluated with the diagnosis made 3 years later.The PredictAD tool achieved the overall accuracy of 72% (sensitivity 73%, specificity 71% in predicting the AD diagnosis. The corresponding number for a clinician's prediction with the assistance of the PredictAD tool was 71% (sensitivity 75%, specificity 68%. Diagnosis with the PredictAD tool was significantly better than diagnosis by biomarkers alone or the combinations of clinical diagnosis of hippocampal pattern for the memory loss and biomarkers (p≤0.037.With the assistance of PredictAD tool, the clinician can predict AD conversion more accurately than the current diagnostic criteria.

  17. AdS5 backgrounds with 24 supersymmetries

    Science.gov (United States)

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

    2016-06-01

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

  18. Coset construction of AdS particle dynamics

    CERN Document Server

    Heinze, Martin; Megrelidze, Luka

    2016-01-01

    We analyze dynamics of the AdS$_{N+1}$ particle realized on the coset SO$(2,N)/$SO$(1,N)$. Hamiltonian reduction provides the physical phase space in terms of the coadjoint orbit obtained by boosting a timelike element of ${\\frak so}(2,N)$. We show equivalence of this approach to geometric quantization and to the SO$(N)$ covariant oscillator description, for which the boost generators entail a complicated operator ordering. As an alternative scheme, we introduce dual oscillator variables and derive their algebra at the classical and the quantum level. This simplifies the calculations of the commutators for the boost generators and leads to unitary irreducible representations of ${\\frak so}(2,N)$ for all admissible values of the mass parameter. We furthermore discuss a SO$(N)$ covariant supersymmetric extensions of the oscillator quantization, with its realization for superparticles in AdS$_2$ and AdS$_3$ given by recent works.

  19. ADS on WWW: Doubling Yearly for Five Years

    Science.gov (United States)

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

    1998-12-01

    It is now five years since the NASA ADS Abstract Service became available on the World Wide Web, in late winter of 1994. Following the explosive growth of the service (when compared with the old propriatory network access system) in the early months of WWW service, ADS growth has settled to doubling yearly. Currently ADS users make 440,000 queries per month, and receive 8,000,000 bibliographic references and 70,000 full-text articles, as well as abstracts, citation histories, links to data, and links to other data centers. Of the 70,000 full-text articles accessed through ADS each month, already 30% are via pointers to the electronic journals. This number is certain to increase. It is difficult to determine the exact number of ADS users. We track usage by the number of unique ``cookies'' which access ADS, and by the number of unique IP addresses. There are difficulties with each technique. In addition many non-astronomers find ADS through portal sites like Yahoo, which skews the statistics. 10,000 unique cookies access the full-text articles each month, 17,000 make queries, and 30,000 visit the site. 91% of full-text users have cookies, but only 65% of site visitors. From another perspective the number of IP addresses from a single typical research site (STScI) which access the full-text data is within 5% of the number of unique cookies assiociated with full-text use from stsci.edu, and also within 5% of the number of AAS members listing an STScI address. The number of unique IP addresses from STScI which make any sort of query to ADS is 40% higher than this. Those who access the full-text average one article per day, those who make queries average two per day. We believe nearly all active astronomy researchers, as well as students and affiliated professionals use ADS on a regular basis.

  20. Sub-AdS Scale Locality in AdS$_3$/CFT$_2$

    CERN Document Server

    Belin, Alexandre; Jefferson, Robert A; Kabir, Laurens

    2016-01-01

    We investigate sub-AdS scale locality in a weakly coupled toy model of the AdS$_3$/CFT$_2$ correspondence. We find that this simple model has the correct density of states at low and high energies to be dual to Einstein gravity coupled to matter in AdS$_3$. Bulk correlation functions also have the correct behavior at leading order in the large $N$ expansion, but non-local effects emerge at order $1/N$. Our analysis leads to the conjecture that any large $N$ CFT$_2$ that is modular invariant and has the right low-energy density of states is dual to a gravitational theory with sub-AdS scale locality.

  1. Ultraviolet asymptotics for quasiperiodic AdS_4 perturbations

    CERN Document Server

    Craps, Ben; Jai-akson, Puttarak; Vanhoof, Joris

    2015-01-01

    Spherically symmetric perturbations in AdS-scalar field systems of small amplitude epsilon approximately periodic on time scales of order 1/epsilon^2 (in the sense that no significant transfer of energy between the AdS normal modes occurs) have played an important role in considerations of AdS stability. They are seen as anchors of stability islands where collapse of small perturbations to black holes does not occur. (This collapse, if it happens, typically develops on time scales of the order 1/epsilon^2.) We construct an analytic treatment of the frequency spectra of such quasiperiodic perturbations, paying special attention to the large frequency asymptotics. For the case of a self-interacting phi^4 scalar field in a non-dynamical AdS background, we arrive at a fairly complete analytic picture involving quasiperiodic spectra with an exponential suppression modulated by a power law at large mode numbers. For the case of dynamical gravity, the structure of the large frequency asymptotics is more complicated....

  2. An Adaptive Replica Allocation Algorithm in Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    JingZheng; JinshuSu; KanYang

    2004-01-01

    In mobile ad hoc networks (MANET), nodes move freely and the distribution of access requests changes dynamically. Replica allocation in such a dynamic environment is a significant challenge. In this paoer, a dynamic adaptive replica allocation algorithm that can adapt to the nodes motion is proposed to minimize the communication cost of object access. When changes occur in the access requests of the object or the network topology, each replica node collects access requests from its neighbors and makes decisions locally to expand replica to neighbors or to relinquish the replica. The algorithm dynamically adapts the replica allocation scheme to a local optimal one. Simulation results show that our algorithms efficiently reduce the communication cost of object access in MANET environment.

  3. Neighbor-Aware Control in Ad Hoc Networks

    Science.gov (United States)

    2002-12-01

    Neighbor-Aware Contention Resolution Channel access problem in ad hoc networks is a special dynamic leader - election prob- lem in which multiple leaders are...message coordinations. However, the network throughput may drastically degrade when the leader election becomes increasingly competitive due to the

  4. AdS nonlinear instability: moving beyond spherical symmetry

    CERN Document Server

    Dias, Oscar J C

    2016-01-01

    Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation [1,2]. We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied in [2]. In contrast with [2], we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied in [2]. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of [2]. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.

  5. Universal isolation in the AdS landscape

    Science.gov (United States)

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

    2016-12-01

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

  6. The Mixed Phase of Charged AdS Black Holes

    Directory of Open Access Journals (Sweden)

    Piyabut Burikham

    2016-01-01

    Full Text Available We study the mixed phase of charged AdS black hole and radiation when the total energy is fixed below the threshold to produce a stable charged black hole branch. The coexistence conditions for the charged AdS black hole and radiation are derived for the generic case when radiation particles carry charge. The phase diagram of the mixed phase is demonstrated for both fixed potential and charge ensemble. In the dual gauge picture, they correspond to the mixed phase of quark-gluon plasma (QGP and hadron gas in the fixed chemical potential and density ensemble, respectively. In the nuclei and heavy-ion collisions at intermediate energies, the mixed phase of exotic QGP and hadron gas could be produced. The mixed phase will condense and evaporate into the hadron gas as the fireball expands.

  7. Smoothed Transitions in Higher Spin AdS Gravity

    CERN Document Server

    Banerjee, Shamik; Hellerman, Simeon; Hijano, Eliot; Lepage-Jutier, Arnaud; Maloney, Alexander; Shenker, Stephen

    2012-01-01

    We consider CFTs conjectured to be dual to higher spin theories of gravity in AdS_3 and AdS_4. Two dimensional CFTs with W_N symmetry are considered in the lambda=0 (k --> infinity) limit, where they are conjectured to be described by continuous orbifolds. The torus partition function is computed, using reasonable assumptions, and equals that of a free field theory. We find no phase transition at temperatures of order one; the usual Hawking-Page phase transition is removed by the highly degenerate light states associated with conical defect states in the bulk. Three dimensional Chern-Simons-matter CFTs with vector-like matter are considered on T^3, where the dynamics is described by an effective theory for the eigenvalues of the holonomies. Likewise, we find no evidence for a Hawking-Page phase transition at large level k.

  8. Perturbative entanglement thermodynamics for AdS spacetime: Renormalization

    CERN Document Server

    Mishra, Rohit

    2015-01-01

    We study the effect of charged excitations in the AdS spacetime on the first law of entanglement thermodynamics. It is found that `boosted' AdS black holes give rise to a more general form of first law which includes chemical potential and charge density. To obtain this result we have to resort to a second order perturbative calculation of entanglement entropy for small size subsystems. At first order the form of entanglement law remains unchanged even in the presence of charged excitations. But the thermodynamic quantities have to be appropriately `renormalized' at the second order due to the corrections. We work in the perturbative regime where $T_{thermal}\\ll T_E$.

  9. Thermodynamics of Einstein-Proca AdS Black Holes

    CERN Document Server

    Liu, Hai-Shan; Pope, C N

    2014-01-01

    We study static spherically-symmetric solutions of the Einstein-Proca equations in the presence of a negative cosmological constant. We show that the theory admits solutions describing both black holes and also solitons in an asymptotically AdS background. Interesting subtleties can arise in the computation of the mass of the solutions and also in the derivation of the first law of thermodynamics. We make use of holographic renormalisation in order to calculate the mass, even in cases where the solutions have a rather slow approach to the asymptotic AdS geometry. By using the procedure developed by Wald, we derive the first law of thermodynamics for the black hole and soliton solutions. This includes a non-trivial contribution associated with the Proca "charge." The solutions cannot be found analytically, and so we make use of numerical integration techniques to demonstrate their existence.

  10. Note on classical string dynamics on AdS3

    Science.gov (United States)

    Bañados, Máximo; Ritz, Adam

    1999-12-01

    We consider bosonic strings propagating on Euclidean anti-de Sitter space (AdS3), and study in particular the realization of various worldsheet symmetries. We give a proper definition for the Brown-Henneaux asymptotic target space symmetry, when acting on the string action, and derive the Giveon-Kutasov-Seiberg worldsheet contour integral representation simply by using Noether's theorem. We show that making identifications in the target space is equivalent to the insertion of an (exponentiated) graviton vertex operator carrying the corresponding charge. Finally, we point out an interesting relation between 3D gravity and the dynamics of the worldsheet on AdS3. Both theories are described by an SL(2,C)/SU(2) Wess-Zumino-Witten (WZW) model, and we prove that the reduction conditions determined on one hand by worldsheet diffeomorphism invariance, and on the other by the Brown-Henneaux boundary conditions, are the same.

  11. Observing quantum gravity in asymptotically AdS space

    Science.gov (United States)

    Emelyanov, Slava

    2015-12-01

    The question is studied of whether an observer can discover quantum gravity in the semiclassical regime. It is shown that it is indeed possible to probe a certain quantum gravity effect by employing an appropriately designed detector. The effect is related to the possibility of having topologically inequivalent geometries in the path-integral approach at the same time. A conformal field theory (CFT) state which is expected to describe the eternal anti-de Sitter (AdS) black hole in the large-N limit is discussed. It is argued under certain assumptions that the black hole boundary should be merely a patch of the entire AdS boundary. This leads then to a conclusion that that CFT state is the ordinary CFT vacuum restricted to that patch. If existent, the bulk CFT operators can behave as the ordinary semiclassical quantum field theory in the large-N limit in the weak sense.

  12. Semiclassical Virasoro Blocks from AdS$_3$ Gravity

    CERN Document Server

    Hijano, Eliot; Perlmutter, Eric; Snively, River

    2015-01-01

    We present a unified framework for the holographic computation of Virasoro conformal blocks at large central charge. In particular, we provide bulk constructions that correctly reproduce all semiclassical Virasoro blocks that are known explicitly from conformal field theory computations. The results revolve around the use of geodesic Witten diagrams, recently introduced in arXiv:1508.00501, 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$_3$; this approach highlights the chiral nature of Virasoro blocks. These techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.

  13. AdS plane waves, entanglement and mutual information

    CERN Document Server

    Mukherjee, Debangshu

    2014-01-01

    $AdS$ plane wave backgrounds are dual to CFT excited states with energy momentum density $T_{++}=Q$. Building on previous work on entanglement entropy in these and nonconformal brane plane wave backgrounds, we first describe a phenomenological scaling picture for entanglement in terms of "entangling partons". We then study aspects of holographic mutual information in these backgrounds for two strip shaped subsystems, aligned parallel or orthogonal to the flux. We focus on the wide ($Ql^d\\gg 1$) and narrow ($Ql^d\\ll 1$) strip regimes. In the wide strip regime, mutual information exhibits growth with the individual strip sizes and a disentangling transition as the separation between the strips increases, whose behaviour is distinct from the ground and thermal states. In the narrow strip case, our calculations have parallels with "entanglement thermodynamics" for these $AdS$ plane wave deformations. We also discuss some numerical analysis.

  14. N=2 supersymmetric sigma-models in AdS

    CERN Document Server

    Butter, Daniel

    2011-01-01

    We construct the most general N=2 supersymmetric nonlinear sigma-model in four-dimensional anti-de Sitter (AdS) space in terms of N=1 chiral superfields. The target space is shown to be a non-compact hyperkahler manifold restricted to possess a special Killing vector field. A remarkable property of the sigma-model constructed is that the algebra of OSp(2|4) transformations is closed off the mass shell.

  15. Generalised structures for N=1 AdS backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Coimbra, André [Institut für Theoretische Physik & Center for Quantum Engineering and Spacetime Research,Leibniz Universität Hannover,Appelstraße 2, 30167 Hannover (Germany); Strickland-Constable, Charles [Institut de physique théorique, Université Paris Saclay, CEA, CNRS, Orme des Merisiers, F-91191 Gif-sur-Yvette (France)

    2016-11-16

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

  16. SUSY properties of warped AdS3

    Science.gov (United States)

    Jeong, Jaehoon; Colgáin, Eoin Ó.; Yoshida, Kentaroh

    2014-06-01

    We examine supersymmetric properties of null-warped AdS3, or alternatively Schrödinger geometries, dual to putative warped CFTs in two dimensions. We classify super Schrödinger subalgebras of the superalgebra psu(1, 1|2) ⊕ psu(1, 1|2), corresponding to the superconformal algebra of the AdS3 × S3 geometry. We comment on geometric realisations and provide a string theory description with enhanced supersymmetry in terms of intersecting D3-branes. For type IIB supergravity solutions based on T 1,1, we consider the relationship between five-dimensional Schrödinger solutions and their three-dimensional null-warped counterparts, corresponding to R symmetry twists. Finally, we study a family of null-warped AdS3 solutions in a setting where there is an ambiguity over the R symmetry and confirm that, for examples admitting a Kaluza-Klein (KK) reduction to three dimensions, the minimisation of a real superpotential of the three-dimensional gauged supergravity captures the central charge and R symmetry.

  17. N=2 AdS supergravity and supercurrents

    CERN Document Server

    Butter, Daniel

    2011-01-01

    We consider the minimal off-shell formulation for four-dimensional N=2 supergravity with a cosmological term, in which the second compensator is an improved tensor multiplet. We use it to derive a linearized supergravity action (and its dual versions) around the anti-de Sitter (AdS) background in terms of three N=2 off-shell multiplets: an unconstrained scalar superfield, vector and tensor multiplets. This allows us to deduce the structure of the supercurrent multiplet associated with those supersymmetric theories which naturally couple to the supergravity formulation chosen, with or without a cosmological term. Finally, our linearized N=2 AdS supergravity action is reduced to N=1 superspace. The result is a sum of two N=1 linearized actions describing (i) old minimal supergravity; and (ii) an off-shell massless gravitino multiplet. We also derive dual formulations for the massless N=1 gravitino multiplet in AdS. As a by-product of our consideration, we derive the consistent supergravity extension of the N=1 ...

  18. ADS Labs - Supporting Information Discovery in Science Education

    CERN Document Server

    Henneken, Edwin A

    2012-01-01

    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 OCLCs WorldCat catalog. The ADS, through its holdings and innovative techniques available in ADS Labs (http://adslabs.org), offers an environment for information discovery that is unlike any other service currently available to the astrophysics community. Literature discovery and...

  19. Desempenho e características de carcaça de bovinos mestiços de origem leiteira em condições de pastejo, restrito ou “ad libitum”, período das águas = Performance and carcass characteristics of dairy crossbreds bulls in grazing, restricted or “ad libitum”, during rainy season

    Directory of Open Access Journals (Sweden)

    Wellington Samay de Melo

    2006-04-01

    Full Text Available Este trabalho objetivou avaliar o desempenho e as características de carcaça de bovinos mestiços (5/8 Holandês/Zebu em pastejo de “Brachiaria decumbens” com acesso restrito ou “ad libitum”. Utilizaram-se 16 animais com idade e peso médios de 10 meses e 180kg, respectivamente. Os animais foram distribuídos em delineamento de blocos casualizados, nos seguintes tratamentos: PAV = pastejo à vontade e PR = pastejo restrito (4 horas/dia. O período experimental teve duração de 114 dias. Observaram-se diferença entre os tratamentos(PThe aim of this work was to evaluate the performance and carcass characteristic of crossbred bulls (5/8 holstein/zebu in grazing of “Brachiaria decumbens” with restrict access or "ad libitum". 16 animals with an average of age and live weight of 10 months and 180kg respectively were used. The animals were assigned in a randomized block design, according to the following treatments: “ad libitium” grazing (AG and restricted grazing (RG (4 hours/day. The experimental period lasted 114 days. There were statistical differences between the treatments (P<0.05 on final live weight (FLW: 229.83 and 207.42 kg for unlimited grazing and restricted grazing, respectively, as well as for average daily gain (ADG: 0.618 and 0.230 kg. There were also statistical differences between the treatments (P<0.05 to final empty body weight, daily empty body weight gain, hot and cold carcass weight, cold carcass yield (CCY/FLW and loin eye area according to the two methods used. The performance of the animals in restricted grazing had satisfactory results to the rainy season in pasture of Brachiaria decumbens. Themethods to determine the loin eye area did not differ. However, the "plastic grid" is more recommended.

  20. Enhancing the performance of ad hoc wireless networks with smart antennas

    CERN Document Server

    Bandyopadhyay, Somprakash; Ueda, Tetsuro

    2006-01-01

    A large portion of the network capacity of an ad hoc network can be wasted by the medium access mechanisms of omni-directional antennas. To overcome this problem, researchers propose the use of directional or adaptive antennas that largely reduce radio interference, improving the utilization of wireless medium and the resulting network throughput.Enhancing the Performance of Ad Hoc Wireless Networks with Smart Antennas discusses these issues and challenges. Following an introduction to ad hoc networks, it presents an overview of basic Media Access Control (MAC) and routing protocols in ad hoc

  1. Intellectual mobile Ad Hoc networks

    OpenAIRE

    Sova, Oleg; Romanjuk, Valeriy; Bunin, Sergey; Zhuk, Pavlo

    2012-01-01

    In this article intellectualization of Mobile Ad Hoc Networks resources management is offered. It was proposed decomposition of the primary goal of MANET functioning into easy subgoals, and fragment of the MANET node target structure is presented.

  2. Supergravity one-loop corrections on AdS7 and AdS3, higher spins and AdS/CFT

    Directory of Open Access Journals (Sweden)

    Matteo Beccaria

    2015-03-01

    Full Text Available As was shown earlier, the one-loop correction in 10d supergravity on AdS5×S5 corresponds to the contributions to the vacuum energy and 4d boundary conformal anomaly which are minus the values for one N=4 Maxwell supermultiplet, thus reproducing the subleading term in the N2−1 coefficient in the dual SU(N SYM theory. We perform similar one-loop computations in 11d supergravity on AdS7×S4 and 10d supergravity on AdS3×S3×T4. In the AdS7 case we find that the corrections to the 6d conformal anomaly a-coefficient and the vacuum energy are again minus the ones for one (2,0 tensor multiplet, suggesting that the total a-anomaly coefficient for the dual (2,0 theory is 4N3−9/4N−7/4 and thus vanishes for N=1. In the AdS3 case the one-loop correction to the vacuum energy or 2d central charge turns out to be equal to that of one free (4,4 scalar multiplet, i.e. is c=+6. This reproduces the subleading term in the central charge c=6(Q1Q5+1 of the dual 2d CFT describing decoupling limit of D5–D1 system. We also present the expressions for the 6d a-anomaly coefficient and vacuum energy contributions of general-symmetry higher spin field in AdS7 and consider their application to tests of vectorial AdS/CFT with the boundary conformal 6d theory represented by free scalars, spinors or rank-2 antisymmetric tensors.

  3. Entanglement Temperature and Perturbed AdS$_3$ Geometry

    CERN Document Server

    Levine, Gregory

    2015-01-01

    In analogy to the first law of thermodynamics, the increase in entanglement entropy $\\delta S$ of a conformal field theory (CFT) is proportional to the increase in energy, $\\delta E$, of the subsystem divided by an effective entanglement temperature, $T_E$. Extending this analogy, we study entanglement entropy when the subsystem is perturbed by applying an external field, expressed as a coupling to a local marginal operator in the CFT. We show that the resulting entropy change is associated with a change in the entanglement temperature itself, leading to an equation analogous to the Clausius relation. Using AdS/CFT duality we develop a relationship between a perturbation in the local entanglement temperature, $\\delta T_E(x)$ of the CFT and the perturbation of the bulk AdS metric. Using the AdS$_3$ minimal surface as a probe, we can construct bulk metric perturbations from an exact numerical computation of the entanglement temperature in a two dimensional $c=1$ boundary theory deformed by a marginal perturbati...

  4. Ultraviolet asymptotics and singular dynamics of AdS perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel, and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University, Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel, and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Vanhoof, Joris [Theoretische Natuurkunde, Vrije Universiteit Brussel, and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)

    2015-10-12

    Important insights into the dynamics of spherically symmetric AdS-scalar field perturbations can be obtained by considering a simplified time-averaged theory accurately describing perturbations of amplitude ε on time-scales of order 1/ε{sup 2}. The coefficients of the time-averaged equations are complicated expressions in terms of the AdS scalar field mode functions, which are in turn related to the Jacobi polynomials. We analyze the behavior of these coefficients for high frequency modes. The resulting asymptotics can be useful for understanding the properties of the finite-time singularity in solutions of the time-averaged theory recently reported in the literature. We highlight, in particular, the gauge dependence of this asymptotics, with respect to the two most commonly used gauges. The harsher growth of the coefficients at large frequencies in higher-dimensional AdS suggests strengthening of turbulent instabilities in higher dimensions. In the course of our derivations, we arrive at recursive relations for the coefficients of the time-averaged theory that are likely to be useful for evaluating them more efficiently in numerical simulations.

  5. Robust message routing for mobile (wireless) ad hoc networks.

    Energy Technology Data Exchange (ETDEWEB)

    Goldsby, Michael E.; Johnson, Michael M.; Kilman, Dominique Marie (Sandia National Laboratories, Albuquerque, NM); Bierbaum, Neal Robert; Chen, Helen Y.; Ammerlahn, Heidi R.; Tsang, Rose P.; Nicol, David M. (University of Illinois, Urbana, IL)

    2004-01-01

    This report describes the results of research targeting improvements in the robustness of message transport in wireless ad hoc networks. The first section of the report provides an analysis of throughput and latency in the wireless medium access control (MAC) layer and relates the analysis to the commonly used 802.11 protocol. The second section describes enhancements made to several existing models of wireless MAC and ad hoc routing protocols; the models were used in support of the work described in the following section. The third section of the report presents a lightweight transport layer protocol that is superior to TCP for use in wireless networks. In addition, it introduces techniques that improve the performance of any ad hoc source routing protocol. The fourth section presents a novel, highly scalable ad hoc routing protocol that is based on geographic principles but requires no localization hardware.

  6. Coherent Cascade: Collapsing Solutions in Global AdS

    CERN Document Server

    Freivogel, Ben

    2015-01-01

    We analyze the gravitational dynamics of a classical scalar field that sometimes leads to blackhole formation in asymptotically AdS spacetime at the shortest nonlinear time scale. We present strong evidence that the dynamics is governed by a "coherent cascade", with all modes remaining in phase as the energy flows to higher frequencies into a power-law spectrum. Using a coherent phase ansatz, we analytically find these power-law solutions. We show how the particular power is determined by the scaling properties of the interaction coefficients. Our result agrees with existing numerical results in 4+1 dimensions, and makes predictions in higher dimensions.

  7. Configurational entropy of charged AdS black holes

    Science.gov (United States)

    Lee, Chong Oh

    2017-09-01

    When we consider charged AdS black holes in higher dimensional spacetime and a molecule number density along coexistence curves is numerically extended to higher dimensional cases. It is found that a number density difference of a small and large black holes decrease as a total dimension grows up. In particular, we find that a configurational entropy is a concave function of a reduced temperature and reaches a maximum value at a critical (second-order phase transition) point. Furthermore, the bigger a total dimension becomes, the more concave function in a configurational entropy while the more convex function in a reduced pressure.

  8. Internal Structure of Charged AdS Black Holes

    CERN Document Server

    Bhattacharjee, Srijit; Virmani, Amitabh

    2016-01-01

    When an electrically charged black hole is perturbed its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached. Nevertheless, the mass inflation singularity is still a weak singularity: although spacetime curvature becomes infinite, tidal distortions remain finite on physical objects attempting to cross it.

  9. Duality invariance of s≥32 fermions in AdS

    Directory of Open Access Journals (Sweden)

    S. Deser

    2014-11-01

    Full Text Available We 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 m2/M2≠0 that turn them into sums of effectively massless unconstrained helicity ±(s,⋯,32 excitations, shorn of the lowest (non-dual helicity ±12-rung and — more generally — of succeeding higher rung as well. Each helicity mode is separately duality invariant, like its flat space counterpart.

  10. Reentrant Phase Transitions in Rotating AdS Black Holes

    CERN Document Server

    Altamirano, Natacha; Mann, Robert B

    2013-01-01

    We study the thermodynamics of higher-dimensional singly spinning asymptotically AdS black holes in the canonical (fixed J) ensemble of extended phase space, where the cosmological constant is treated as pressure and the corresponding conjugate quantity is interpreted as thermodynamic volume. Along with the usual small/large black hole phase transition, we find a new phenomenon of reentrant phase transitions for all d>5 dimensions, in which a monotonic variation of the temperature yields two phase transitions from large to small and back to large black holes. This situation is similar to that seen in multicomponent liquids.

  11. Entanglement entropy and duality in AdS4

    Directory of Open Access Journals (Sweden)

    Ioannis Bakas

    2015-07-01

    Full Text Available Small variations of the entanglement entropy δS and the expectation value of the modular Hamiltonian δE are computed holographically for circular entangling curves in the boundary of AdS4, using gravitational perturbations with general boundary conditions in spherical coordinates. Agreement with the first law of thermodynamics, δS=δE, requires that the line element of the entangling curve remains constant. In this context, we also find a manifestation of electric–magnetic duality for the entanglement entropy and the corresponding modular Hamiltonian, following from the holographic energy–momentum/Cotton tensor duality.

  12. Most general AdS_3 boundary conditions

    CERN Document Server

    Grumiller, Daniel

    2016-01-01

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

  13. M-Theory solutions with AdS factors

    CERN Document Server

    Gauntlett, J P; Pakis, S; Waldram, D; Gauntlett, Jerome P.; Kim, Nakwoo; Pakis, Stathis; Waldram, Daniel

    2002-01-01

    Solutions of D=7 maximal gauged supergravity are constructed with metrics that are a product of a n-dimensional anti-de Sitter (AdS) space, with n=2,3,4,5, and certain Einstein manifolds. The gauge fields have the same form as in the recently constructed solutions describing the near-horizon limits of M5-branes wrapping supersymmetric cycles. The new solutions do not preserve any supersymmetry and can be uplifted to obtain new solutions of D=11 supergravity, which are warped and twisted products of the D=7 metric with a squashed four-sphere. Some aspects of the stability of the solutions are discussed.

  14. M-theory solutions with AdS factors

    Energy Technology Data Exchange (ETDEWEB)

    Gauntlett, Jerome P [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Kim, Nakwoo [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); Pakis, Stathis [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Waldram, Daniel [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom)

    2002-08-07

    Solutions of D=7 maximal gauged supergravity are constructed with metrics that are a product of an n-dimensional anti-de Sitter (AdS) space, with n=2, 3, 4, 5, and certain Einstein manifolds. The gauge fields have the same form as in the recently constructed solutions describing the near-horizon limits of M5-branes wrapping supersymmetric cycles. The new solutions do not preserve any supersymmetry and can be uplifted to obtain new solutions of D=11 supergravity, which are warped and twisted products of the D=7 metric with a squashed four-sphere. Some aspects of the stability of the solutions are discussed.

  15. Heavy quark potential from deformed AdS5 models

    Science.gov (United States)

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

    2017-04-01

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

  16. AdS Chern-Simons Gravity induces Conformal Gravity

    CERN Document Server

    Aros, Rodrigo

    2013-01-01

    The leitmotif of this paper is the question of whether four- and higher even-dimensional Conformal Gravities do have a Chern-Simons pedigree. We show that Weyl gravity can be obtained as dimensional reduction of a five-dimensional Chern-Simons action for a suitable (gauged-fixed, tractor-like) five-dimensional AdS connection. The gauge-fixing and dimensional reduction program admits a readily generalization to higher dimensions for the case of certain conformal gravities obtained by contractions of the Weyl tensor.

  17. ADS Labs: Supporting Information Discovery in Science Education

    Science.gov (United States)

    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.

  18. Rindler-AdS/CFT

    CERN Document Server

    Parikh, Maulik

    2012-01-01

    In anti-de Sitter space a highly accelerating observer perceives a Rindler horizon. The two Rindler wedges in AdS_{d+1} are holographically dual to an entangled conformal field theory that lives on two boundaries with geometry R x H_{d-1}. For AdS_3, the holographic duality is especially tractable, allowing quantum-gravitational aspects of Rindler horizons to be probed. We recover the thermodynamics of Rindler-AdS space directly from the boundary conformal field theory. We derive the temperature from the two-point function and obtain the Rindler entropy density precisely, including numerical factors, using the Cardy formula. We also probe the causal structure of the spacetime, and find from the behavior of the one-point function that the CFT "knows" when a source has fallen across the Rindler horizon. This is so even though, from the bulk point of view, there are no local signifiers of the presence of the horizon. Finally, we discuss an alternate foliation of Rindler-AdS which is dual to a CFT living in de Si...

  19. The CFT dual of AdS gravity with torsion

    CERN Document Server

    Klemm, Dietmar

    2007-01-01

    We consider the Mielke-Baekler model of three-dimensional AdS gravity with torsion, which has gravitational and translational Chern-Simons terms in addition to the usual Einstein-Hilbert action with cosmological constant. It is shown that the topological nature of the model leads to a finite Fefferman-Graham expansion. We derive the holographic stress tensor and the associated Ward identities and show that, due to the asymmetry of the left- and right-moving central charges, a Lorentz anomaly appears in the dual conformal field theory. Both the consistent and the covariant Weyl and Lorentz anomaly are determined, and the Wess-Zumino consistency conditions for the former are verified. Moreover we consider the most general solution with flat boundary geometry, which describes left-and right-moving gravitational waves on AdS_3 with torsion, and shew that in this case the holographic energy-momentum tensor is given by the wave profiles. The anomalous transformation laws of the wave profiles under diffeomorphisms p...

  20. AdS nonlinear instability: moving beyond spherical symmetry

    Science.gov (United States)

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

    2016-12-01

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

  1. AdS pure spinor superstring in constant backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Chandia, Osvaldo [Departamento de Ciencias, Facultad de Artes Liberales, Universidad Adolfo Ibáñez,Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez,Diagonal Las Torres 2640, Peñalolén, Santiago (Chile); Bevilaqua, L. Ibiapina [Escola de Ciências e Tecnologia, Universidade Federal do Rio Grande do Norte,Caixa Postal 1524, 59072-970, Natal, RN (Brazil); Vallilo, Brenno Carlini [Facultad de Ciencias Exactas, Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile)

    2014-06-05

    In this paper we study the pure spinor formulation of the superstring in AdS{sub 5}×S{sup 5} around point particle solutions of the classical equations of motion. As a particular example we quantize the pure spinor string in the BMN background.

  2. A special road to AdS vacua

    CERN Document Server

    Cassani, Davide; Marrani, Alessio; Morales, Jose F; Samtleben, Henning

    2010-01-01

    We apply the techniques of special Kaehler geometry to investigate AdS_4 vacua of general N=2 gauged supergravities underlying flux compactifications of type II theories. We formulate the scalar potential and its extremization conditions in terms of a triplet of prepotentials P_x and their special Kaehler covariant derivatives only, in a form that recalls the potential and the attractor equations of N=2 black holes. We propose a system of first order equations for the P_x which generalize the supersymmetry conditions and yield non-supersymmetric vacua. Special geometry allows us to recast these equations in algebraic form, and we find an infinite class of new N=0 and N=1 AdS_4 solutions, displaying a rich pattern of non-trivial charges associated with NSNS and RR fluxes. Finally, by explicit evaluation of the entropy function on the solutions, we derive a U-duality invariant expression for the cosmological constant and the central charges of the dual CFT's.

  3. AdS twistors for higher spin theory

    CERN Document Server

    Cederwall, M

    2004-01-01

    We construct spectra of supersymmetric higher spin theories in D=4, 5 and 7 from twistors describing massless (super-)particles on AdS spaces. A massless twistor transform is derived in a geometric way from classical kinematics. Relaxing the spin-shell constraints on twistor space gives an infinite tower of massless states of a ``higher spin particle'', generalising previous work of Bandos et al. This can generically be done in a number of ways, each defining the states of a distinct higher spin theory, and the method provides a systematic way of finding these. We reproduce known results in D=4, minimal supersymmetric 5- and 7-dimensional models, as well as supersymmetrisations of Vasiliev's Sp-models as special cases. In the latter models a dimensional enhancement takes place, meaning that the theory lives on a space of higher dimension than the original AdS space, and becomes a theory of doubletons. This talk was presented at the XIXth Max Born Symposium ``Fundamental Interactions and Twistor-Like Methods''...

  4. Enthalpy and the Mechanics of AdS Black Holes

    CERN Document Server

    Kastor, David; Traschen, Jennie

    2009-01-01

    We present geometric derivations of the Smarr formula for static AdS black holes and an expanded first law that includes variations in the cosmological constant. These two results are further related by a scaling argument based on Euler's theorem. The key new ingredient in the constructions is a two-form potential for the static Killing field. Surface integrals of the Killing potential determine the coefficient of the variation of the cosmological constant in the first law. This coefficient is proportional to a finite, effective volume for the region outside the AdS black hole horizon, which can also be interpreted as minus the volume excluded from a spatial slice by the black hole horizon. This effective volume also contributes to the Smarr formula. Since the cosmological constant is naturally thought of as a pressure, the new term in the first law has the form of effective volume times change in pressure that arises in the variation of the enthalpy in classical thermodynamics. This and related arguments sug...

  5. Quantum cat map dynamics on AdS$_2$

    CERN Document Server

    Axenides, Minos; Nicolis, Stam

    2016-01-01

    We present a toy model for the chaotic unitary scattering of single particle wave packets on the radial AdS$_2$ geometry of extremal BH horizons. Based on our recent work for the discretization of the AdS$_2$ space-time, which describes a finite and random geometry, by modular arithmetic, we investigate the validity of the eigenstate thermalization hypothesis (ETH), as well as that of the fast scrambling time bound conjecture (STB), for an observer with time evolution operator the quantum Arnol'd cat map (QACM). We find that the QACM, while possessing a linear spectrum, has eigenstates, which can be expressed in closed form, are found to be random and to satisfy the assumptions of the ETH.The implications are that the dynamics is described by a chaotic, unitary, single particle S-matrix, which completely delocalizes and randomizes initial gaussian wave packets . Applying results obtained by Dyson and Falk for the periods of the Arnol'd Cat Map(ACM),which are related to its mixing time, we also find that the t...

  6. Smooth Causal Patches for AdS Black Holes

    CERN Document Server

    Raju, Suvrat

    2016-01-01

    We review the paradox of low energy excitations about an AdS black hole. 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 analy...

  7. AdCell: Ad Allocation in Cellular Networks

    CERN Document Server

    Alaei, Saeed; Liaghat, Vahid; Pei, Dan; Saha, Barna

    2011-01-01

    With more than four billion usage of cellular phones worldwide, mobile advertising has become an attractive alternative to online advertisements. In this paper, we propose a new targeted advertising policy for Wireless Service Providers (WSPs) via SMS or MMS- namely {\\em AdCell}. In our model, a WSP charges the advertisers for showing their ads. Each advertiser has a valuation for specific types of customers in various times and locations and has a limit on the maximum available budget. Each query is in the form of time and location and is associated with one individual customer. In order to achieve a non-intrusive delivery, only a limited number of ads can be sent to each customer. Recently, new services have been introduced that offer location-based advertising over cellular network that fit in our model (e.g., ShopAlerts by AT&T) . We consider both online and offline version of the AdCell problem and develop approximation algorithms with constant competitive ratio. For the online version, we assume tha...

  8. ADS 2.0: New Architecture, API and Services

    Science.gov (United States)

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

    2015-09-01

    The ADS platform is undergoing the biggest rewrite of its 20-year history. While several components have been added to its architecture over the past couple of years, this talk will concentrate on the underpinnings of ADS's search layer and its API. To illustrate the design of the components in the new system, we will show how the new ADS user interface is built exclusively on top of the API using RESTful web services. Taking one step further, we will discuss how we plan to expose the treasure trove of information hosted by ADS (10 million records and fulltext for much of the Astronomy and Physics refereed literature) to partners interested in using this API. This will provide you (and your intelligent applications) with access to ADS's underlying data to enable the extraction of new knowledge and the ingestion of these results back into the ADS. Using this framework, researchers could run controlled experiments with content extraction, machine learning, natural language processing, etc. In this talk, we will discuss what is already implemented, what will be available soon, and where we are going next.

  9. Online Ad Slotting With Cancellations

    CERN Document Server

    Constantin, Florin; Muthukrishnan, S; Pal, Martin

    2008-01-01

    Many advertisers buy advertisements (ads) on the Internet or on traditional media and seek simple, online mechanisms to reserve ad slots in advance. Media publishers represent a vast and varying inventory, and they too seek automatic, online mechanisms for pricing and allocating such reservations. In this paper, we present and study a simple model for auctioning such ad slots in advance. Bidders arrive sequentially and report which slots they are interested in. The seller must decide immediately whether or not to grant a reservation. Our model allows a seller to accept reservations, but possibly cancel the allocations later and pay the bidder a cancellation compensation (bump payment). Our main result is an online mechanism to derive prices and bump payments that is efficient to implement. This mechanism has many desirable properties. It is individually rational; winners have an incentive to be honest and bidding one's true value dominates any lower bid. Our mechanism's efficiency is within a constant fractio...

  10. Adding momentum to supersymmetric geometries

    Energy Technology Data Exchange (ETDEWEB)

    Lunin, Oleg, E-mail: olunin@albany.edu [Department of Physics, University at Albany (SUNY), Albany, NY 12222 (United States); Mathur, Samir D., E-mail: mathur.16@osu.edu [Department of Physics, Ohio State University, Columbus, OH 43210 (United States); Turton, David, E-mail: turton.7@osu.edu [Department of Physics, Ohio State University, Columbus, OH 43210 (United States)

    2013-03-11

    We consider general supersymmetric solutions to minimal supergravity in six dimensions, trivially lifted to IIB supergravity. To any such solution we add a traveling wave deformation involving the additional directions. The deformed solution is given in terms of a function which is harmonic in the background geometry. We also present a family of explicit examples describing microstates of the D1-D5 system on T{sup 4}. In the case where the background contains a large AdS region, the deformation is identified as corresponding to an action of a U(1) current of the D1-D5 orbifold CFT on a given state.

  11. Adding momentum to supersymmetric geometries

    CERN Document Server

    Lunin, Oleg; Turton, David

    2012-01-01

    We consider general supersymmetric solutions to minimal supergravity in six dimensions, trivially lifted to IIB supergravity. To any such solution we add a travelling-wave deformation involving the additional directions. The deformed solution is given in terms of a function which is harmonic in the background geometry. We also present a family of explicit examples describing microstates of the D1-D5 system on T^4. In the case where the background contains a large AdS region, the deformation is identified as corresponding to an action of a U(1) current of the D1-D5 orbifold CFT on a given state.

  12. Voice Service Support in Mobile Ad Hoc Networks

    CERN Document Server

    Jiang, Hai; Poor, H Vincent; Zhuang, Weihua

    2007-01-01

    Mobile ad hoc networks are expected to support voice traffic. The requirement for small delay and jitter of voice traffic poses a significant challenge for medium access control (MAC) in such networks. User mobility makes it more complex due to the associated dynamic path attenuation. In this paper, a MAC scheme for mobile ad hoc networks supporting voice traffic is proposed. With the aid of a low-power probe prior to DATA transmissions, resource reservation is achieved in a distributed manner, thus leading to small delay and jitter. The proposed scheme can automatically adapt to dynamic path attenuation in a mobile environment. Simulation results demonstrate the effectiveness of the proposed scheme.

  13. Ad valorem versus unit taxes

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Sørensen, Allan

    2010-01-01

    a general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit...

  14. Added Value via SPI supplement

    Science.gov (United States)

    Supplement that indicates where to find the source data sets on the EPA system.This dataset is associated with the following publication:Bowden, J., K.D. Talgo, T. Spero , and C. Nolte. Assessing the Added Value of Dynamical Downscaling Using the Standardized Precipitation Index. ADVANCES IN METEOROLOGY. Hindawi Publishing Corporation, New York, NY, USA, 2016(8432064): 14 pages, (2016).

  15. Holographic properties in three-dimensional AdS soliton using $AdS_3/CFT_2$

    CERN Document Server

    Peng, Yan

    2016-01-01

    We study the holographic description of a superconductor by the $AdS_{3}/CFT_{2}$ correspondence. The system is constructed with a Maxwell field and a charged scalar field coupled in the (2+1)-dimensional AdS soliton background. With analytical methods, we obtain the exact expression for the critical chemical potential as $\\mu_{c} = 1 + \\sqrt{1+m^2}$, which has also been generalized to higher dimensions as $\\mu_c \\thickapprox a + \\sqrt{m^2-m_{BF}^2}$ in this work. Around the phase transition points, we find a correspondence between the value of the scalar field at the tip and the scalar operator at infinity. We also arrive at the classical second order phase transition threshold exponent $\\beta=\\frac{1}{2}$ as the same as the mean field theory near the critical chemical potential. As the condensation becomes heavier, we show surprisingly that superconducting phases exist only in a certain range of the chemical potential, which is very different from higher-dimensional cases. And for the small enough negative ...

  16. Brownian motion in AdS/CFT

    NARCIS (Netherlands)

    de Boer, J.; Hubeny, V.E.; Rangamani, M.; Shigemori, M.

    2009-01-01

    We study Brownian motion and the associated Langevin equation in AdS/CFT. The Brownian particle is realized in the bulk spacetime as a probe fundamental string in an asymptotically AdS black hole background, stretching between the AdS boundary and the horizon. The modes on the string are excited by

  17. Colliding waves on a string in AdS$_3$

    CERN Document Server

    Vegh, David

    2015-01-01

    This paper is concerned with the classical motion of a string in global AdS$_3$. The initially static string stretches between two antipodal points on the boundary circle. Both endpoints are perturbed which creates cusps at a steady rate. The cusps propagate towards the interior where they collide. The behavior of the string depends on the strength of forcing. Three qualitatively different phases can be distinguished: transparent, gray, and black. The transparent region is analogous to a standing wave. In the black phase, there is a horizon on the worldsheet and cusps never reach the other endpoint. The string keeps folding and its length grows linearly over time. In the gray phase, the string still grows linearly. However, cusps do cross to the other side. The transparent and gray regions are separated by a transition point where a logarithmic accumulation of cusps is numerically observed. A simple model reproduces the qualitative behavior of the string in the three phases.

  18. Bootstrapping Pure Quantum Gravity in AdS3

    CERN Document Server

    Bae, Jin-Beom; Lee, Sungjay

    2016-01-01

    The three-dimensional pure quantum gravity with negative cosmological constant is supposed to be dual to the extremal conformal field theory of central charge $c=24k$ in two dimensions. We employ the conformal bootstrap method to analyze the extremal CFTs, and find numerical evidence for the non-existence of the extremal CFTs for sufficiently large central charge ($k \\ge 20$). We also explore near-extremal CFTs, a small modification of extremal ones, and find similar evidence for their non-existence for large central charge. This indicates, under the assumption of holomorphic factorization, the pure gravity in the weakly curved AdS$_3$ do not exist as a consistent quantum theory.

  19. On jordanian deformations of AdS5 and supergravity

    Science.gov (United States)

    Hoare, Ben; van Tongeren, Stijn J.

    2016-10-01

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

  20. On jordanian deformations of AdS_5 and supergravity

    CERN Document Server

    Hoare, Ben

    2016-01-01

    We consider various homogeneous Yang-Baxter deformations of the AdS_5 x S^5 superstring that can be obtained from the eta-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the eta-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which should imply that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which also do not correspond to supergravity solutions.

  1. Higher spins on AdS3 from the worldsheet

    Science.gov (United States)

    Ferreira, Kevin; Gaberdiel, Matthias R.; Jottar, Juan I.

    2017-07-01

    It was recently shown that the CFT dual of string theory on AdS3 × S3 × T 4, the symmetric orbifold of T 4, contains a closed higher spin subsector. Via holography, this makes precise the sense in which tensionless string theory on this background contains a Vasiliev higher spin theory. In this paper we study this phenomenon directly from the worldsheet. Using the WZW description of the background with pure NS-NS flux, we identify the states that make up the leading Regge trajectory and show that they fit into the even spin N=4 Vasiliev higher spin theory. We also show that these higher spin states do not become massless, except for the somewhat singular case of level k = 1 where the theory contains a stringy tower of massless higher spin fields coming from the long string sector.

  2. Thermodynamics of charged Lovelock: AdS black holes

    Science.gov (United States)

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

    2016-04-01

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

  3. Jet physics from static charges in AdS space

    Science.gov (United States)

    Chien, Yang-Ting; Schwartz, Matthew D.; Simmons-Duffin, David; Stewart, Iain W.

    2012-02-01

    Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, become static charges in Euclidean AdS. The anomalous dimension of the corresponding Wilson line operator is then determined by the potential energy of the charges. To study these Wilson lines we introduce a “conformal gauge” which does not have kinetic mixing between radial and angular directions, and show that a number of properties of Wilson lines are reproduced through relatively simple calculations. For example, certain nonplanar graphs involving multiple Wilson lines automatically vanish. We also discuss the linear growth of the charges’ imaginary potential energy with separation, and a relationship between Wilson line diagrams and Witten diagrams.

  4. Jet Physics from Static Charges in AdS

    CERN Document Server

    Chien, Yang-Ting; Simmons-Duffin, David; Stewart, Iain W

    2011-01-01

    Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, become static charges in Euclidean AdS. The anomalous dimension of the corresponding Wilson line operator is then determined by the potential energy of the charges. To study these Wilson lines we introduce a "conformal gauge" which does not have kinetic mixing between radial and angular directions, and show that a number of properties of Wilson lines are reproduced through relatively simple calculations. For example, certain non-planar graphs involving multiple Wilson lines automatically vanish. We also discuss the linear growth of the charges' imaginary potential energy with separation, and a relationship between Wilson line diagrams and Witten diagrams.

  5. An Investigation of AdS2 Backreaction and Holography

    CERN Document Server

    Engelsöy, Julius; Verlinde, Herman

    2016-01-01

    We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski and develop an 1D effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1D version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.

  6. On Information Loss in AdS$_3$/CFT$_2$

    CERN Document Server

    Fitzpatrick, A Liam; Li, Daliang; Wang, Junpu

    2016-01-01

    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 the behavior of correlators at times $t \\sim S_{BH}$, 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 correspo...

  7. Supersymmetry Properties of AdS Supergravity Backgrounds

    Science.gov (United States)

    Beck, Samuel; Gutowski, Jan; Papadopoulos, George

    2017-01-01

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

  8. Thermodynamics of charged Lovelock: AdS black holes

    Energy Technology Data Exchange (ETDEWEB)

    Prasobh, C.B.; Suresh, Jishnu; Kuriakose, V.C. [Cochin University of Science and Technology, Department of Physics, Cochin (India)

    2016-04-15

    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. (orig.)

  9. Adiabatic pumping solutions in global AdS

    Science.gov (United States)

    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.

  10. Worldsheet dilatation operator for the AdS superstring

    Energy Technology Data Exchange (ETDEWEB)

    Ramírez, Israel [Departamento de Física, Universidad Técnica Federico Santa María,Casilla 110-V, Valparaíso (Chile); Institut für Mathematik und Institut für Physik, Humboldt-Universität zu Berlin,IRIS Haus, Zum Großen Windkanal 6, 12489 Berlin (Germany); Vallilo, Brenno Carlini [Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile)

    2016-05-23

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

  11. Islands of stability and recurrence times in AdS

    CERN Document Server

    Green, Stephen R; Lehner, Luis; Liebling, Steven L

    2015-01-01

    We study the stability of anti-de Sitter (AdS) spacetime to spherically symmetric perturbations of a real scalar field in general relativity. Further, we work within the context of the "two time framework" (TTF) approximation, which describes the leading nonlinear effects for small amplitude perturbations, and is therefore suitable for studying the weakly turbulent instability of AdS---including both collapsing and non-collapsing solutions. We have previously identified a class of quasi-periodic (QP) solutions to the TTF equations, and in this work we analyze their stability. We show that there exist several families of QP solutions that are stable to linear order, and we argue that these solutions represent islands of stability in TTF. We extract the eigenmodes of small oscillations about QP solutions, and we use them to predict approximate recurrence times for generic non-collapsing initial data in the full (non-TTF) system. Alternatively, when sufficient energy is driven to high-frequency modes, as occurs ...

  12. Holographic reconstruction of AdS exchanges from crossing symmetry

    Science.gov (United States)

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

    2017-08-01

    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× O OPE of a scalar primary O , what is its total contribution to the vacuum four-point function theories at leading order in 1/ N. Viewed holographically, this provides a field theory reconstruction of crossing-symmetric, four-point exchange amplitudes in AdS5. Our solution takes the form of a resummation of the large spin solution to the crossing equations, supplemented by corrections at 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.

  13. AdS/CFT Duality User Guide

    CERN Document Server

    Natsuume, Makoto

    2014-01-01

    This is the draft version of a textbook on "real-world" applications of the AdS/CFT duality for beginning graduate students in particle physics and for researchers in the other fields. The aim of this book is to provide background materials such as string theory, general relativity, nuclear physics, nonequilibrium physics, and condensed-matter physics as well as some key applications of the AdS/CFT duality in a single textbook. Contents: (1) Introduction, (2) General relativity and black holes, (3) Black holes and thermodynamics, (4) Strong interaction and gauge theories, (5) The road to AdS/CFT, (6) The AdS spacetime, (7) AdS/CFT - equilibrium, (8) AdS/CFT - adding probes, (9) Basics of nonequilibrium physics, (10) AdS/CFT - nonequilibrium, (11) Other AdS spacetimes, (12) Applications to quark-gluon plasma, (13) Basics of phase transition, (14) AdS/CFT - phase transition.

  14. Enhanced Reputation Mechanism for Mobile Ad Hoc Networks

    OpenAIRE

    Liu, Jinshan; Issarny, Valérie

    2004-01-01

    International audience; Interactions between entities unknown to each other are inevitable in the ambient intelligence vision of service access anytime, anywhere. Trust management through a reputation mechanism to facilitate such interactions is recognized as a vital part of mobile ad hoc networks, which features lack of infrastructure, autonomy, mobility and resource scarcity of composing light-weight terminals. However, the design of a reputation mechanism is faced by challenges of how to e...

  15. Mobile Ad-Hoc Networking on Android Devices

    Science.gov (United States)

    2014-03-01

    done to take advantage of High Performance Computer ( HPC ) resources seeded within the mobile ad-hoc network. Having access to HPC resources allows the...are provided by the device manufacturers . Because of this, we could enable IBSS with the same modified kernel. Unfortunately, using the same chipset and...source project called MANET Manager (9), which ports the OLSR daemon to Android devices. With this additional software we were able to successfully

  16. Facilities Management and Added Value

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2010-01-01

    Aim: This paper aims to present different models of the concept of the added value of Facilities Management (FM), including the FM Value Map, which forms the basis of research group in EuroFM, and to present some of the results of this research collaboration. Approach and methodology: The paper...... on the aimed output) and the internal resource based view (with a focus on the input from FM and RE). Good relationship management and building on trust shows to be equally important as delivering the agreed services. In order to measure the multi-dimensional components of adding value both qualitative...... is based on literature reviews of the most influential journals within the academic fields of FM, Corporate Real Estate Management and Business to Business Marketing and discussions between participants of the research group working on a further exploration and testing of the FM Value Map. Conclusions...

  17. The PredictAD project

    DEFF Research Database (Denmark)

    Antila, Kari; Lötjönen, Jyrki; Thurfjell, Lennart;

    2013-01-01

    can be managed. Today the significance of early and precise diagnosis of AD is emphasized in order to minimize its irreversible effects on the nervous system. When new drugs and therapies enter the market it is also vital to effectively identify the right candidates to benefit from these. The main...... candidates and implement the framework in software. The results are currently used in several research projects, licensed to commercial use and being tested for clinical use in several trials....

  18. Scattering States in AdS/CFT

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, A.Liam; /Boston U.; Kaplan, Jared; /SLAC

    2012-02-14

    We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.

  19. MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Omar Elizarraras

    2014-01-01

    Full Text Available The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15% compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput.

  20. Multiagent Based Information Dissemination in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    S.S. Manvi

    2009-01-01

    Full Text Available Vehicular Ad hoc Networks (VANETs are a compelling application of ad hoc networks, because of the potential to access specific context information (e.g. traffic conditions, service updates, route planning and deliver multimedia services (Voice over IP, in-car entertainment, instant messaging, etc.. This paper proposes an agent based information dissemination model for VANETs. A two-tier agent architecture is employed comprising of the following: 1 'lightweight', network-facing, mobile agents; 2 'heavyweight', application-facing, norm-aware agents. The limitations of VANETs lead us to consider a hybrid wireless network architecture that includes Wireless LAN/Cellular and ad hoc networking for analyzing the proposed model. The proposed model provides flexibility, adaptability and maintainability for traffic information dissemination in VANETs as well as supports robust and agile network management. The proposed model has been simulated in various network scenarios to evaluate the effectiveness of the approach.

  1. VT Limited Access Highways

    Data.gov (United States)

    Vermont Center for Geographic Information — A limited-access road, known by various terms worldwide, including limited-access highway, dual carriageway, expressway, and partial controlled access highway, is a...

  2. Holography in 3D AdS gravity with torsion

    CERN Document Server

    Blagojević, Milutin; Miskovic, Olivera; Olea, Rodrigo

    2013-01-01

    Basic aspects of the AdS/CFT correspondence are studied in the framework of 3-dimensional gravity with torsion. After choosing a consistent holographic ansatz, we formulate an improved approach to the Noether--Ward identities for the boundary theory. The method is applied first to the topological Mielke--Baekler model, and then to the more interesting (parity-preserving) 3-dimensional gravity with propagating torsion. In both cases, we find the finite holographic energy-momentum and spin currents and obtain the associated (anomalous) Noether--Ward identities.

  3. Towards Timelike Singularity via AdS Dual

    CERN Document Server

    Bhowmick, Samrat

    2016-01-01

    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 minimal surfaces including spacelike geodesics. Finally, we compute correlators of highly massive operators in the boundary field theory with a geodesic approximation.

  4. Canonical energy and hairy AdS black holes

    CERN Document Server

    Hyun, Seungjoon; Yi, Sang-Heon

    2016-01-01

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

  5. Fishing Access Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish & Wildlife Department maintains developed fishing access areas. These sites provide public access to waters in Vermont for shore fishing...

  6. Access to the Online Planetary Research Literature

    Science.gov (United States)

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

    2009-12-01

    The SAO/NASA Astrophysics Data System (ADS) provides various free services for finding, accessing, and managing bibliographic data, including a basic search form, the myADS notification service, and private library capabilities (a useful tool for building bibliographies), plus access to scanned pages of published articles. The ADS also provides powerful search capabilities, allowing users to find e.g. the most instructive or most important articles on a given subject . For the Planetary Sciences, the citation statistics of the ADS have improved considerably with the inclusion of the references from Elsevier journals, including Icarus, Planetary and Space Science, and Earth and Planetary Science Letters. We currently have about 78 journals convering the planetary and space sciences (Advances in Space Research, Icarus, Solar Physics, Astrophusics and Space Science, JGRE, Meteoritics, to name a few). Currently, this set of journals represents about 180,000 articles and 1.1 million references. Penetration into the Solar Physics, Planetary Sciences and Geophysics community has increased significantly. During the period 2004-2008, user access to JGR and Icarus increased by a factor of 4.4, while e.g. access to the Astrophysical Journal "only" increased by a factor of 1.8.

  7. Random Access to Grammar-Compressed Strings

    DEFF Research Database (Denmark)

    Bille, Philip; Landau, Gad M.; Raman, Rajeev

    2011-01-01

    (n) is the inverse of the kth row of Ackermann's function. Our representations also efficiently support decompression of any substring in S: we can decompress any substring of length m in the same complexity as a single random access query and ad- ditional O(m) time. Combining these results with fast algorithms...

  8. Stability of Charged Global AdS$_4$ Spacetimes

    CERN Document Server

    Arias, Raúl; Serantes, Alexandre

    2016-01-01

    We study linear and nonlinear stability of asymptotically AdS$_4$ solutions in Einstein-Maxwell-scalar theory. After summarizing the set of static solutions we first examine thermodynamical stability in the grand canonical ensemble and the phase transitions that occur among them. In the second part of the paper we focus on nonlinear stability in the microcanonical ensemble by evolving radial perturbations numerically. We find hints of an instability corner for vanishingly small perturbations of the same kind as the ones present in the uncharged case. Collapses are avoided, instead, if the charge and mass of the perturbations come to close the line of solitons. Finally we examine the soliton solutions. The linear spectrum of normal modes is not resonant and instability turns on at extrema of the mass curve. Linear stability extends to nonlinear stability up to some threshold for the amplitude of the perturbation. Beyond that, the soliton is destroyed and collapses to a hairy black hole. The relative width of t...

  9. AdS crunches, CFT falls, and cosmological complexity

    CERN Document Server

    Barbón, José Luis

    2015-01-01

    This chapter discusses the holographic description of crunching AdS cosmologies. Crunching FRW models with hyperbolic spatial sections are dual to semiclassical condensates in deformed de Sitter (dS) CFTs. dS-invariant condensates with a sharply defined energy scale are induced by effective negative-definite relevant or marginal operators, which may or may not destabilize the CFT. This result is obtained by explicitly constructing a “complementarity map” for this model, given by a conformal transformation of the dS CFT into a static time-frame, which reveals the crunch as an infinite potential-energy fall in finite time. Quite generically, the crunch is associated with a finite-mass black hole if the dS O(d, 1) invariance is an accidental IR symmetry, broken to U(1) × O(d) in the UV. Any such regularization cuts off the eternity of dS spacetime. Equivalently, the dimension of the Hilbert space propagating into the crunch is finite only when dS is not eternal.

  10. F-theory and AdS3/CFT2

    Science.gov (United States)

    Couzens, Christopher; Lawrie, Craig; Martelli, Dario; Schäfer-Nameki, Sakura; Wong, Jin-Mann

    2017-08-01

    We construct supersymmetric AdS3 solutions in F-theory, that is Type IIB supergravity with varying axio-dilaton, which are holographically dual to 2d N=(0,4) superconformal field theories with small superconformal algebra. In F-theory these arise from D3-branes wrapped on curves in the base of an elliptically fibered Calabi-Yau threefold Y 3 and correspond to self-dual strings in the 6d N=(1,0) theory obtained from F-theory on Y 3. The non-trivial fibration over the wrapped curves implies a varying coupling of the N=4 Super-Yang-Mills theory on the D3-branes. We compute the holographic central charges and show that these agree with the field theory and with the anomalies of self-dual strings in 6d. We complement our analysis with a discussion of the dual M-theory solutions and a comparison of the central charges.

  11. On modular properties of the AdS3 CFT

    CERN Document Server

    Baron, Walter

    2010-01-01

    We study modular properties of the AdS3 WZNW model. Although the Euclidean partition function is modular invariant, the characters on the Euclidean torus are ill-defined and their modular transformations are unknown. We reconsider the characters defined on the Lorentzian torus, focusing on their structure as distributions. We find a generalized S matrix, depending on the sign of the real modular parameters, which has two diagonal blocks and one off-diagonal block, mixing discrete and continuous representations, that we fully determine. We then explore the relations among the modular transformations, the fusion algebra and the boundary states. We explicitly construct Ishibashi states for the maximally symmetric D-branes and show that the generalized S matrix defines the one-point functions associated to point-like and H2 branes as well as the fusion rules of the degenerate representations of SL(2,R) appearing in the open string spectrum of the point-like D-branes, through a generalized Verlinde theorem.

  12. The ADS All Sky Survey

    Science.gov (United States)

    Goodman, Alyssa

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

  13. Operational Reconnaissance for the Anti-Access /Area Denial environment

    Science.gov (United States)

    2015-04-01

    computational power equivalent to two supercomputers.20 This impressive analytical capacity gives the pilot a coherent, real -time understanding of...performing Operational Reconnaissance in Anti-Access/Area Denial (A2/AD) environments. Contested battlespace is radically different from the permissive...AD environment. After gaining access to this airspace, fighters can use a variety of sensors to provide commanders with a real -time understanding of

  14. Noncommutative AdS2/CFT1 duality: The case of massless scalar fields

    Science.gov (United States)

    Pinzul, A.; Stern, A.

    2017-09-01

    We show how to construct correlators for the CFT1 which is dual to noncommutative AdS2 (n c AdS2). We do it explicitly for the example of the massless scalar field on Euclidean n c AdS2. n c AdS2 is the quantization of AdS2 that preserves all the isometries. It is described in terms of the unitary irreducible representations, more specifically discrete series representations, of s o (2 ,1 ). We write down symmetric differential representations for the discrete series and then map them to functions on the Moyal-Weyl plane. The Moyal-Weyl plane has a large distance limit which can be identified with the boundary of n c AdS2. Killing vectors can be constructed on n c AdS2 which reduce to the AdS2 Killing vectors near the boundary. We, therefore, conclude that n c AdS2 is asymptotically AdS2, and so the AdS /CFT correspondence should apply. For the example of the massless scalar field on Euclidean n c AdS2, the on-shell action, and resulting two-point function for the boundary theory, are computed to leading order in the noncommutativity parameter. The computation is nontrivial because nonlocal interactions appear in the Moyal-Weyl description. Nevertheless, the result is remarkably simple and agrees with that of the commutative scalar field theory, up to a rescaling.

  15. JISC Open Access Briefing Paper

    OpenAIRE

    Swan, Alma

    2005-01-01

    What Open Access is. What Open Access is not. How is Open Access provided? Open Access archives or repositories. Open Access journals. Why should authors provide Open Access to their work? Further information and resources

  16. JISC Open Access Briefing Paper

    OpenAIRE

    Swan, Alma

    2005-01-01

    What Open Access is. What Open Access is not. How is Open Access provided? Open Access archives or repositories. Open Access journals. Why should authors provide Open Access to their work? Further information and resources

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

    Science.gov (United States)

    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 decreased hunger (P decreased prospective consumption (P 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.

  18. EFFECTS OF MAIZE GRAIN ADDED IN A DIET BASED ON ALFALFA HAYLAGE ON THE RATION QUALITY IN WETHER SHEEP

    Directory of Open Access Journals (Sweden)

    Marina Vranić

    2011-06-01

    Full Text Available The objective of this experiment was to study the effects of interactions between alfalfa haylage (AH and maize grain (MG (5 vs. 10 g d-1 kg-1 body weight on ad libitum intake, water intake and dry matter (DM digestibility in wether sheep. The AH and MG contained 534.7 and 915.1g DM kg-1 fresh sample respectively, while crude protein (CP concentration was 141 and 106.0 g kg-1DM. Adding of MG (5 or 10 g kg-1 body weight d-1 into AH based ration resulted in linear increase in diet DM intake (g kg-1 M0,75, linear decrease in water intake (P<0.01 and linear increase in diet DM digestibility (P<0,001. A positive associative response of MG supplementation to AH based ration was observed for DM intake (P<0.001 and DM digestibility (P<0.001. No improvements in DM intake were recorded with 10 g MG added kg-1 body weight d-1 in comparison with 5 g MG added kg-1 body weight d-1.

  19. Entanglement Entropy of AdS Black Holes

    Directory of Open Access Journals (Sweden)

    Maurizio Melis

    2010-11-01

    Full Text Available We review recent progress in understanding the entanglement entropy of gravitational configurations for anti-de Sitter gravity in two and three spacetime dimensions using the AdS/CFT correspondence. We derive simple expressions for the entanglement entropy of two- and three-dimensional black holes. In both cases, the leading term of the entanglement entropy in the large black hole mass expansion reproduces exactly the Bekenstein-Hawking entropy, whereas the subleading term behaves logarithmically. In particular, for the BTZ black hole the leading term of the entanglement entropy can be obtained from the large temperature expansion of the partition function of a broad class of 2D CFTs on the torus.

  20. The reliability of puff topography and subjective responses during ad lib smoking of a single cigarette.

    Science.gov (United States)

    Perkins, Kenneth A; Karelitz, Joshua L; Giedgowd, Grace E; Conklin, Cynthia A

    2012-04-01

    Acute smoking behavior (i.e., puff topography) and subjective responses during the ad lib smoking of a single cigarette in the laboratory may provide useful measures of smoking reinforcement and reward, respectively. However, the reliability of such measures is not clear, leaving uncertain the utility of a single assessment of smoking behavior as an individual difference measure. Dependent smokers (N = 94) smoked normally prior to each of 4 laboratory sessions during which they were instructed to smoke 1 cigarette of their preferred brand in ad libitum and unblinded fashion and then rate it for subjective effects. Puff topography (puff number, total volume, and maximum volume) was assessed via portable Clinical Research Support System device. Subjective reward and perception were assessed by visual analog scales of "liking" and "how strong," respectively. The reliability of puff topography and subjective measures was determined across days by intra-class correlations (ICCs). Differences due to sex and nicotine dependence (high and low Fagerström Test for Nicotine Dependence score) were also examined. Reliability was highly significant for each measure. ICCs were .70 for total puff volume, .60 for maximum puff volume, .73 for puff number, .64 for liking, and .78 for how strong. Reliability generally did not differ by sex or dependence, but absolute values for total volume and maximum puff volume were greater in men and in high dependent smokers. Liking was also greater in high dependent smokers. Puff topography and subjective measures during the ad lib smoking of a single cigarette are highly reliable. Smoking responses during a single ad lib smoking session may be useful in identifying stable individual differences in smoking reinforcement and reward.

  1. Adding a Scripting Interface to Gaudi

    Institute of Scientific and Technical Information of China (English)

    ChristopherT.Day; DavidQuarrie; 等

    2001-01-01

    Athena,the Software Framework for ATLAS' offline software is based on the Gaudi Framework from LHCb1,The Processing Model of Gaudi is essentially that of a batch-oriented system -a User prepares a file detailing the configuration of which Algorithms are to be applied to the input data of a job and the parameter values that control the behavior of each Algorithm instance.The Framework then reads that file once at the beginning of a job and runs to completion with no further interaction with the User. We have enhanced the Processing Model to include an interactive mode where a User can cotrol the event loop of a running job and modify the Algorithms and parameters on the fly.We changed only a very small number of Gaudi Classes to provide access to parameters from an embedded Python interpreter,No change was made to the Gaudi Programming Model.i.e., developers need not change anything to make use of this added interface,We present details of the design and implementation of the interactive Python interface for Athena.

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

    Science.gov (United States)

    2015-03-01

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

  3. CERN Access Cards and Access Authorisations

    CERN Multimedia

    2003-01-01

    From the 01/05/2003, all problems relating to access cards and refusal of access to any zone, building or experiment within CERN must be addressed to the Centrale de Surveillance des Accès (CSA building 120) on 78877 or send an e-mail to Access.Surveillance@cern.ch. The responsibles for CERN access control have put into place a procedure with the CSA, Service Enregistrement and the Technical Control Room, to make sure that all problems get resolved in a proper and timely manner.

  4. ANNALS OF GEOPHYSICS: AD MAJORA

    Directory of Open Access Journals (Sweden)

    Fabio Florindo

    2014-03-01

    Full Text Available Annals of Geophysics is a bimonthly international journal, which publishes scientific papers in the field of geophysics sensu lato. It derives from Annali di Geofisica, which commenced publication in January 1948 as a quarterly periodical devoted to general geophysics, seismology, earth magnetism, and atmospheric studies. The journal was published regularly for a quarter of a century until 1982 when it merged with the French journal Annales de Géophysique to become Annales Geophysicae under the aegis of the European Geophysical Society. In 1981, this journal ceased publication of the section on solid earth geophysics, ending the legacy of Annali di Geofisica. In 1993, the Istituto Nazionale di Geofisica (ING, founder of the journal, decided to resume publication of its own journal under the same name, Annali di Geofisica. To ensure continuity, the first volume of the new series was assigned the volume number XXXVI (following the last issue published in 1982. In 2002, with volume XLV, the name of the journal was translated into English to become Annals of Geophysics and in consequence the journal impact factor counter was restarted. Starting in 2010, in order to improve its status and better serve the science community, Annals of Geophysics has instituted a number of editorial changes including full electronic open access, freely accessible online, the possibility to comment on and discuss papers online, and a board of editors representing Asia and the Americas as well as Europe. [...

  5. Accessibility and sensory experiences

    DEFF Research Database (Denmark)

    Ryhl, Camilla

    2010-01-01

    This article introduces a new design concept; sensory accessibility. While acknowledging the importance of sensory experiences in architectural quality, as well as the importance of accommodating user needs the concept combines three equally important factors; architecture, the senses and accessi......This article introduces a new design concept; sensory accessibility. While acknowledging the importance of sensory experiences in architectural quality, as well as the importance of accommodating user needs the concept combines three equally important factors; architecture, the senses...... and accessibility. Sensory accessibility accommodates aspects of a sensory disability and describes architectural design requirements needed to ensure access to architectural experiences. In the context of architecture accessibility has become a design concept of its own. It is generally described as ensuring...... physical access to the built environment by accommodating physical disabilities. While the existing concept of accessibility ensures the physical access of everyone to a given space, sensory accessibility ensures the choice of everyone to stay and be able to participate and experience....

  6. 76 FR 79553 - Maintaining Access to Emergency Liquidity

    Science.gov (United States)

    2011-12-22

    ... Federal Reserve District Bank. 12 CFR 201.51. While the CLF is a special liquidity facility for the credit... ADMINISTRATION 12 CFR Part 741 RIN 3133-AD96 Maintaining Access to Emergency Liquidity AGENCY: National Credit... regulation to require federally insured credit unions (FICUs) to have access to backup federal...

  7. 75 FR 35439 - Medical Diagnostic Equipment Accessibility Standards

    Science.gov (United States)

    2010-06-22

    ...) amended the Rehabilitation Act of 1973 by adding Section 510 to the Rehabilitation Act. Section 510 of the Rehabilitation Act requires the Architectural and Transportation Barriers Compliance Board (Access Board), in consultation with the Food and Drug Administration, to issue accessibility standards for medical...

  8. MUSICAL ARRANGEMENT OF MEDIA ADS

    Directory of Open Access Journals (Sweden)

    Chernyshov Alexander V.

    2015-01-01

    Full Text Available The music-compositional principles of commercial and political advertising and also the self-promotion of electronic media (radio, television, Internet are considered in this mediatext: from the elementary beeps, symbolic functions, emblems/logos and musical brands to the sound engineering technology to underscore the product's name and the complex synthesis between music and intra movements and color-light design of frames. Simultaneously examines, how the musical arrangement of ethereal advertising is involved in creation the emotional drama or bravado which reach the level of explicit or associative counterpoint 'music with the advertised object or subject' and which extend to expression of cultural image of all the broadcast channel. The article explores the works of the next genres like infomercial, teleshopping, film-ad, and autonomous commercials that have been produced in European countries or USA.

  9. Ad valorem versus unit taxes

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Sørensen, Allan

    2010-01-01

    Real-world industries are composed from heterogeneous firms and substantial intra-industry reallocations take place, i.e. high productivity firms squeeze out low productivity firms. Previous tax-tool comparisons have not included these central forces of industry structure. This paper examines...... a general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit...... taxes distort relative prices, which in turn reduces average industry productivity through reallocations (the survival and increased market share of lower productivity firms). Importantly, numerical solutions of the model reveal that the relative welfare loss from using the unit tax increases...

  10. Adding timing to the VELO

    CERN Document Server

    Mitreska, Biljana

    2017-01-01

    The LHCb experiment is designed to perform high precision measurements of matter-antimatter asymmetries and searches for rare and forbidden decays, with the aim of discovering new and unexpected particles and forces. In 2030 the LHC beam intensity will increase by a factor of 50 compared to current operations. This means increased samples of the particles we need to study, but it also presents experimental challenges. In particular, with current technology it becomes impossible to differentiate the many (>50) separate proton-proton collisions which occur for each bunch crossing.\\\\ In this project a Monte Carlo simulation was developed to model the operation of a silicon pixel vertex detector surrounding the collision region at LHCb, under the conditions expected after 2030, after the second upgrade of the Vertex Locator(VELO).The main goal was studying the effect of adding '4D' detectors which save high-precision timing information, in addition to the usual three spatial coordinates, as charged particles pas...

  11. Stringy Membranes in AdS/CFT

    CERN Document Server

    Axenides, Minos; Linardopoulos, Georgios

    2013-01-01

    We study membrane configurations in AdS_{7/4}xS^{4/7}. The membranes are wrapped around the compact manifold S^{4/7} and are dynamically equivalent to bosonic strings in AdS_5. We thus conveniently identify them as "stringy membranes". For the case of AdS_7xS^4, their construction is carried out by embedding the Polyakov action for classical bosonic strings in AdS_5, into the corresponding membrane action. Therefore, every string configuration in AdS_5 can be realized by an appropriately chosen stringy membrane in AdS_7xS^4. We discuss the possibility of this being also the case for stringy membranes in AdS_4xS^7/Z^k (k > 1 or k = 1). By performing a stability analysis to the constructed solutions, we find that the (membrane) fluctuations along their transverse directions are organized in multiple Lam\\'{e} stability bands and gaps in the space of parameters of the configurations. In this membrane picture, strings exhibit a single band/gap structure. Since the spectrum of quadratic fluctuations is important fo...

  12. World Wide Access: Accessible Web Design.

    Science.gov (United States)

    Washington Univ., Seattle.

    This brief paper considers the application of "universal design" principles to Web page design in order to increase accessibility for people with disabilities. Suggestions are based on the World Wide Web Consortium's accessibility initiative, which has proposed guidelines for all Web authors and federal government standards. Seven guidelines for…

  13. Organoleptic and physico-chemical evaluation of capretto baladi goats: a value-added meat alternative in an extensive rearing system

    Directory of Open Access Journals (Sweden)

    S. Abi Saab

    2017-06-01

    Full Text Available Abi Saab, S. Esseily, F. Saliba, M. and Aad P. 2017. Organoleptic and physico-chemical evaluation of capretto baladi goats: a value-added meat alternative in an extensive rearing system. Lebanese Science Journal. 18(1: 73-80. The local Baladi breed is considered a common source of fresh meat in Lebanon. Due to the extensive rearing system and the scarcity of pasture, kids resulting from multiple births are not reared, though cultural preference for young meat may valorize these twin kids as an expensive delicacy. Few studies observed growth parameters, physical-chemical and sensory properties of meat in Baladi kids. Therefore, 24 male Baladi kids were fed milk ad libitum post-natally for 24 days, after which 9 were randomly selected and fed pasture grass ad libitum and goat milk (Control, and 15 were fed only milk (Capretto twice per day. Animals were slaughtered at 4, 6 and 8 weeks of age and body organs compared. Feed intake was measured by weighing kids pre- and post- feeding, and body weight measured twice per week. Meat chemical properties were total ether-extracted fat, kjeldhal protein, and minerals. Meat organoleptic properties were evaluated by consumers for color, taste, odor, richness, juiciness, tenderness and overall appreciation, as cooked by housewives or professionals. Data were analyzed as a CRD using SPSS 10.0 and presented as LSMeans ± SEM. Results showed that Capretto consumed increasing levels of milk from 4 to 8 weeks, with ADG decreasing (P 0.05 between Capretto and control, although capretto showed lower (p<0.05 meat fat content than control kids. Meat organoleptic characteristics were desirable at weeks 4 and 6 for both Capretto and control kids, whereas only Capretto meat stayed desirable at week 8. To conclude, Capretto kids have similar properties to their traditional counterparts, with added desirable properties for a longer growing period, in addition to the increased health benefit of lower fat content.

  14. Access Nets: Modeling Access to Physical Spaces

    Science.gov (United States)

    Frohardt, Robert; Chang, Bor-Yuh Evan; Sankaranarayanan, Sriram

    Electronic, software-managed mechanisms using, for example, radio-frequency identification (RFID) cards, enable great flexibility in specifying access control policies to physical spaces. For example, access rights may vary based on time of day or could differ in normal versus emergency situations. With such fine-grained control, understanding and reasoning about what a policy permits becomes surprisingly difficult requiring knowledge of permission levels, spatial layout, and time. In this paper, we present a formal modeling framework, called AccessNets, suitable for describing a combination of access permissions, physical spaces, and temporal constraints. Furthermore, we provide evidence that model checking techniques are effective in reasoning about physical access control policies. We describe our results from a tool that uses reachability analysis to validate security policies.

  15. Spiky strings in AdS_3 x S^1 and their AdS-pp-wave limits

    CERN Document Server

    Ishizeki, R; Tirziu, A; Tseytlin, A A

    2008-01-01

    We study a class of classical solutions for closed strings moving in AdS_3 x S^1 part of AdS_5 x S^5 with energy E and spin S in AdS_3 and angular momentum J and winding m in S^1. They have rigid shape with n spikes in AdS_3. We find that when J or m are non-zero, the spikes do not end in cusps. We consider in detail a special large n limit in which S ~ n^2, J ~ n, i.e. S >> J >> 1, with (E+S)/ n^2, (E-S)/ n, J/n, m/n staying finite. In that limit the spiky spinning string approaches the boundary of AdS_5. We show that the corresponding solution can be interpreted as describing a periodic-spike string moving in AdS_3 --pp-wave x S^1 background. The resulting expression for the string energy should represent a strong-coupling prediction for anomalous dimension of a class of dual gauge theory states in a particular thermodynamic limit of the SL(2) spin chain.

  16. LAMAN: Load Adaptable MAC for Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Realp Marc

    2005-01-01

    Full Text Available In mobile ad hoc radio networks, mechanisms on how to access the radio channel are extremely important in order to improve network efficiency. In this paper, the load adaptable medium access control for ad hoc networks (LAMAN protocol is described. LAMAN is a novel decentralized multipacket MAC protocol designed following a cross-layer approach. Basically, this protocol is a hybrid CDMA-TDMA-based protocol that aims at throughput maximization in multipacket communication environments by efficiently combining contention and conflict-free protocol components. Such combination of components is used to adapt the nodes' access priority to changes on the traffic load while, at the same time, accounting for the multipacket reception (MPR capability of the receivers. A theoretical analysis of the system is developed presenting closed expressions of network throughput and packet delay. By simulations the validity of our analysis is shown and the performances of a LAMAN-based system and an Aloha-CDMA-based one are compared.

  17. Professional Access 2013 programming

    CERN Document Server

    Hennig, Teresa; Hepworth, George; Yudovich, Dagi (Doug)

    2013-01-01

    Authoritative and comprehensive coverage for building Access 2013 Solutions Access, the most popular database system in the world, just opened a new frontier in the Cloud. Access 2013 provides significant new features for building robust line-of-business solutions for web, client and integrated environments.  This book was written by a team of Microsoft Access MVPs, with consulting and editing by Access experts, MVPs and members of the Microsoft Access team. It gives you the information and examples to expand your areas of expertise and immediately start to develop and upgrade projects. Exp

  18. Recurring Anomaly Detection System (ReADS)

    Data.gov (United States)

    National Aeronautics and Space Administration — Overview: ReADS can analyze text reports, such as aviation reports and problem or maintenance records. ReADS uses text clustering algorithms to group loosely related...

  19. TV Snack Ads Make Preschoolers Snack More

    Science.gov (United States)

    ... Sesame Street" interrupted by TV ads for a salty snack food ended up eating more of that ... watched the show with commercials for a popular salty snack. The ads depicted kids happily playing and ...

  20. The AdS/CFT/Unparticle Correspondence

    CERN Document Server

    Cacciapaglia, Giacomo; Terning, John

    2009-01-01

    We examine the correspondence between the anti-de Sitter (AdS) description of conformal field theories (CFTs) and the unparticle description of CFTs. We show how unparticle actions are equivalent to holographic boundary actions for fields in AdS, and how massive unparticles provide a new type of infrared cutoff that can be simply implemented in AdS by a soft breaking of conformal symmetry. We also show that processes involving scalar unparticles with dimensions d_s<2 or fermion unparticles with dimensions d_f<5/2 are insensitive to ultraviolet cutoff effects. Finally we show that gauge interactions for unparticles can be described by bulk gauge interactions in AdS and that they correspond to minimal gauging of the non-local effective action, and we compute the fermion unparticle production cross-section.

  1. TASI lectures on AdS/CFT

    CERN Document Server

    Penedones, Joao

    2017-01-01

    We introduce the AdS/CFT correspondence as a natural extension of QFT in a fixed AdS background. We start by reviewing some general concepts of CFT, including the embedding space formalism. We then consider QFT in a fixed AdS background and show that one can define boundary operators that enjoy very similar properties as in a CFT, except for the lack of a stress tensor. Including a dynamical metric in AdS generates a boundary stress tensor and completes the CFT axioms. We also discuss some applications of the bulk geometric intuition to strongly coupled QFT. Finally, we end with a review of the main properties of Mellin amplitudes for CFT correlation functions and their uses in the context of AdS/CFT.

  2. Condom ads promote illicit sex.

    Science.gov (United States)

    Kippley, J F

    1994-01-01

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

  3. Security Ads in Mobile Apps

    Directory of Open Access Journals (Sweden)

    Manasvi Kalra,

    2016-02-01

    Full Text Available The apps consist of advertisements to promote their products. Not all of them are appropriate to resume. Therefore various algorithms have been used in order to block those apps from existence but none of them is completely successful. In our app we are using an antivirus which can by default block those spy apps and remove them from the web page. The algorithm which has been used makes use of various ant viruses in the background which detect irrelevant and intimate apps and then our algorithm will demolish them. Certain apps are non-trustworthy where one click can spy all the mobile data. They block those apps and works on security. We are working on secure ads for mobile apps. It can also work as a basic antivirus where it detects the viruses like malwares in any of your installed apps or downloads. It will create a popup of discarding or keeping it. Mobile applications can be downloaded from anywhere like amazon, googleplay, apps store etc. There is no rigorous verification of an application when it is uploaded to the market. One can easily develop a malicious application and upload it to the app market. The user itself is responsible for accepting the risk of an app available from secondary markets. Therefore, we have decided to develop this app to make the market more secure and bounded. In future, It will take the mobile market while consuming minimal additional resources and preserving user privacy.

  4. Material Developing for ADS Beam Window

    Institute of Scientific and Technical Information of China (English)

    XUYong-li; XUYuan-chao; LIHua-qing; NINGGuang-sheng; WANFa-rong; ZHAOFei

    2003-01-01

    The irradiation damage and the chemical interaction with the coolant for the ADS target and the structure materials are the key issues in ADS engineering. The developing of the materials that are irradiation and corrosion resistance is the important topic in ADS program in many countries. In this case,a topic of the material developing for the beam window has been proposed in our ADS program.

  5. Myths & Facts about Value-Added Analysis

    Science.gov (United States)

    TNTP, 2011

    2011-01-01

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

  6. Extending Service Area of IEEE 802.11 Ad Hoc Networks

    Science.gov (United States)

    Choi, Woo-Yong

    2012-06-01

    According to the current IEEE 802.11 wireless LAN standards, IEEE 802.11 ad hoc networks have the limitation that all STAs (Stations) are in the one-hop transmission range of each other. In this paper, to alleviate the limitation of IEEE 802.11 ad hoc networks we propose the efficient method for selecting the most appropriate pseudo AP (Access Point) from among the set of ad hoc STAs and extending the service area of IEEE 802.11 ad hoc networks by the pseudo AP's relaying the internal traffic of IEEE 802.11 ad hoc networks. Numerical examples show that the proposed method significantly extends the service area of IEEE 802.11 ad hoc networks.

  7. Support the Open Access Movement

    CERN Multimedia

    2005-01-01

    CERN's Executive Board recently endorsed a new policy of open access to the laboratory's results: Continuing CERN action on Open Access (OA) [http://cds.cern.ch/record/828991/files/open-2005-006.pdf]. What does this policy mean for you? CERN authors have two responsibilities: Submit your document to the CERN Document Server; Consider submitting future articles to an Open Access journal. Since 2001, Operational Circular No. 6 has required every CERN author (Staff member, Fellow, or any Associated member of personnel who is allowed to use CERN as his affiliation) to submit a copy of their scientific documents to the CERN Document Server (CDS). For some groups all approved documents are submitted by the secretary (see the Departments' policies at: http://library.cern.ch/cern_publications/cern_publication_policy.html). Each author should personally also ensure the submission of any other articles which are not added in this way, such as conference contributions and review articles. It is not sufficient to re...

  8. Automated Experiments on Ad Privacy Settings

    Directory of Open Access Journals (Sweden)

    Datta Amit

    2015-04-01

    Full Text Available To partly address people’s concerns over web tracking, Google has created the Ad Settings webpage to provide information about and some choice over the profiles Google creates on users. We present AdFisher, an automated tool that explores how user behaviors, Google’s ads, and Ad Settings interact. AdFisher can run browser-based experiments and analyze data using machine learning and significance tests. Our tool uses a rigorous experimental design and statistical analysis to ensure the statistical soundness of our results. We use AdFisher to find that the Ad Settings was opaque about some features of a user’s profile, that it does provide some choice on ads, and that these choices can lead to seemingly discriminatory ads. In particular, we found that visiting webpages associated with substance abuse changed the ads shown but not the settings page. We also found that setting the gender to female resulted in getting fewer instances of an ad related to high paying jobs than setting it to male. We cannot determine who caused these findings due to our limited visibility into the ad ecosystem, which includes Google, advertisers, websites, and users. Nevertheless, these results can form the starting point for deeper investigations by either the companies themselves or by regulatory bodies.

  9. 16 CFR 460.18 - Insulation ads.

    Science.gov (United States)

    2010-01-01

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

  10. Ad-Coop Positioning System (ACPS)

    DEFF Research Database (Denmark)

    Frattasi, Simone; Monti, Marco

    2008-01-01

    In this paper, we propose an innovative solution for positioning determination in 4G wireless networks by introducing the Ad-Coop Positioning System (ACPS). The ACPS is supported by a hybrid cellular ad-hoc architecture, where the cellular network has a centralized control over the ad...

  11. Design for Accessibility

    DEFF Research Database (Denmark)

    Herriott, Richard

    2012-01-01

    A report on how nine rail builder, operators and transport designers deal with design for accessibility......A report on how nine rail builder, operators and transport designers deal with design for accessibility...

  12. Ontology Based Access Control

    Directory of Open Access Journals (Sweden)

    Özgü CAN

    2010-02-01

    Full Text Available As computer technologies become pervasive, the need for access control mechanisms grow. The purpose of an access control is to limit the operations that a computer system user can perform. Thus, access control ensures to prevent an activity which can lead to a security breach. For the success of Semantic Web, that allows machines to share and reuse the information by using formal semantics for machines to communicate with other machines, access control mechanisms are needed. Access control mechanism indicates certain constraints which must be achieved by the user before performing an operation to provide a secure Semantic Web. In this work, unlike traditional access control mechanisms, an "Ontology Based Access Control" mechanism has been developed by using Semantic Web based policies. In this mechanism, ontologies are used to model the access control knowledge and domain knowledge is used to create policy ontologies.

  13. Physical Access Control Database -

    Data.gov (United States)

    Department of Transportation — This data set contains the personnel access card data (photo, name, activation/expiration dates, card number, and access level) as well as data about turnstiles and...

  14. Chemists, Access, Statistics

    Science.gov (United States)

    Holmes, Jon L.

    2000-06-01

    New JCE Internet Feature at JCE Online Biographical Snapshots of Famous Chemists is a new JCE Internet feature on JCE Online. Edited by Barbara Burke, this feature provides biographical information on leading chemists, especially women and minority chemists, fostering the attitude that the practitioners of chemistry are as human as those who endeavor to learn about it. Currently, the column features biographical "snapshots" of 30 chemists. Each snapshot includes keywords and bibliography and several contain links to additional online information about the chemist. More biographical snapshots will appear in future installments. In addition, a database listing over 140 women and minority chemists is being compiled and will be made available online with the snapshots in the near future. The database includes the years of birth and death, gender and ethnicity, major and minor discipline, keywords to facilitate searching, and references to additional biographical information. We welcome your input into what we think is a very worthwhile resource. If you would like to provide additional biographical snapshots, see additional chemists added to the database, or know of additional references for those that are already in the database, please contact JCE Online or the feature editor. Your feedback is welcome and appreciated. You can find Biographical Snapshots of Famous Chemists starting from the JCE Online home page-- click the Features item under JCE Internet and then the Chemist Bios item. Access JCE Online without Name and Password We have recently been swamped by libraries requesting IP-number access to JCE Online. With the great benefit IP-number authentication gives to librarians (no user names and passwords to administer) and to their patrons (no need to remember and enter valid names and passwords) this is not surprising. If you would like access to JCE Online without the need to remember and enter a user name and password, you should tell your librarian about our

  15. Access Control Enforcement Testing

    OpenAIRE

    El Kateb, Donia; Elrakaiby, Yehia; Mouelhi, Tejeddine; Le Traon, Yves

    2012-01-01

    A policy-based access control architecture com- prises Policy Enforcement Points (PEPs), which are modules that intercept subjects access requests and enforce the access decision reached by a Policy Decision Point (PDP), the module implementing the access decision logic. In applications, PEPs are generally implemented manually, which can introduce errors in policy enforcement and lead to security vulnerabilities. In this paper, we propose an approach to systematically test and validate the co...

  16. ANALYSIS OF ROUTING IN MOBILE AD-HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    Shweta

    2012-09-01

    Full Text Available An ad-hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any standalone infrastructure or centralized administration. Routing in Ad hoc networks is a challenging problem because nodes are mobile and links are continuously being created and broken.In this model we not only improves the reputation of the network but also provide a routing approach for reliable data transmission and also avoid the loop occurs in the communication. The mobile network is the dynamicnetwork that provides the solution for the inclusion and exclusion of dynamic nodes in the network. AODV and DSR are the two most popular routing protocols for ad-hoc network that we discussed here. In this paper we describe the way to find the node having packet loss and to perform the elimination of node from the network withoutperforming the rerouting and provide the reliable data transfer over the network. In this paper, we design and evaluate cooperative caching techniques to efficiently support data access in the ad-hoc network.

  17. Security Challenges and Attacks in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    CH.V. Raghavendran

    2013-09-01

    Full Text Available Mobile Ad hoc Network (MANET is an autonomous collection of mobile nodes that form a temporary network without of any existing network infrastructure or central access point. The popularity of these networks created security challenges as an important issue. The traditional routing protocols perform well with dynamically changing topology but are not designed to defense against security challenges. In this paper we discuss about current challenges in an ad hoc environment which includes the different types of potential attacks that are possible in the Mobile Ad hoc Networks that can harm its working and operation. We have done literature study and gathered information relating to various types of attacks. In our study, we have found that there is no general algorithm that suits well against the most commonly known attacks. But the complete security solution requires the prevention, detection and reaction mechanisms applied in MANET. To develop suitable security solutions for such environments, we must first understand how MANETs can be attacked. This paper provides a comprehensive study of attacks against mobile ad hoc networks. We present a detailed classification of the attacks against MANETs.

  18. Supergravity on $AdS_{5/4}$ x Hopf Fibrations and Conformal Field Theories

    CERN Document Server

    Halyo, E

    2000-01-01

    We obtain three and four dimensional conformal field theories with less than maximal supersymmetry by using their supergravity duals. These supergravity theories are type II on $AdS_5 \\times CP^2$, IIA on $AdS_4 \\times CP^3$, IIB on $AdS_5 \\times S^5/Z_k$ and D=11 supergravity on $AdS_4 \\times S^7/Z_k$. They are obtained from the spherically compactified ten and eleven dimensional theories by either Hopf reduction or by winding the U(1) fiber over the base.

  19. Supergravity on $AdS_{5/4} \\times$ Hopf Fibrations and Conformal Field Theories

    OpenAIRE

    1998-01-01

    We obtain three and four dimensional conformal field theories with less than maximal supersymmetry by using their supergravity duals. These supergravity theories are type II on $AdS_5 \\times CP^2$, IIA on $AdS_4 \\times CP^3$, IIB on $AdS_5 \\times S^5/Z_k$ and D=11 supergravity on $AdS_4 \\times S^7/Z_k$. They are obtained from the spherically compactified ten and eleven dimensional theories by either Hopf reduction or by winding the U(1) fiber over the base.

  20. Mobile Advertisement in Vehicular Ad-Hoc Networks

    CERN Document Server

    Dobre, Ciprian

    2012-01-01

    Mobile Advertisement is a location-aware dissemination solution built on top of a vehicular ad-hoc network. We envision a network of WiFi access points that dynamically disseminate data to clients running on the car's smart device. The approach can be considered an alternative to the static advertisement billboards and can be useful to business companies wanting to dynamically advertise their products and offers to people driving their car. The clients can subscribe to information based on specific topics. We present design solutions that use access points as emitters for transmitting messages to wireless-enabled devices equipped on vehicles. We also present implementation details for the evaluation of the proposed solution using a simulator designed for VANET application. The results show that the application can be used for transferring a significant amount of data even under difficult conditions, such as when cars are moving at increased speeds, or the congested Wi-Fi network causes significant packet loss...

  1. Opportunistic Channel Scheduling for Ad Hoc Networks with Queue Stability

    Science.gov (United States)

    Dong, Lei; Wang, Yongchao

    2015-03-01

    In this paper, a distributed opportunistic channel access strategy in ad hoc network is proposed. We consider the multiple sources contend for the transmission opportunity, the winner source decides to transmit or restart contention based on the current channel condition. Owing to real data assumption at all links, the decision still needs to consider the stability of the queues. We formulate the channel opportunistic scheduling as a constrained optimization problem which maximizes the system average throughput with the constraints that the queues of all links are stable. The proposed optimization model is solved by Lyapunov stability in queueing theory. The successive channel access problem is decoupled into single optimal stopping problem at every frame and solved with Lyapunov algorithm. The threshold for every frame is different, and it is derived based on the instantaneous queue information. Finally, computer simulations are conducted to demonstrate the validity of the proposed strategy.

  2. Approximate ad-hoc query engine for simulation data

    Energy Technology Data Exchange (ETDEWEB)

    Abdulla, G; Baldwin, C; Critchlow, T; Kamimura, R; Lozares, I; Musick, R; Tang, N; Lee, B S; Snapp, R

    2001-02-01

    In this paper, we describe AQSim, an ongoing effort to design and implement a system to manage terabytes of scientific simulation data. The goal of this project is to reduce data storage requirements and access times while permitting ad-hoc queries using statistical and mathematical models of the data. In order to facilitate data exchange between models based on different representations, we are evaluating using the ASCI common data model which is comprised of several layers of increasing semantic complexity. To support queries over the spatial-temporal mesh structured data we are in the process of defining and implementing a grammar for MeshSQL.

  3. Seven steps for adding value to integrated delivery systems.

    Science.gov (United States)

    O'Malley, S

    1997-01-01

    "Value is a spectrum of needs that you seek to fulfill," says Dean C. Coddington, senior author of Making Integrated Health Care Work. And adding value to products and services is becoming more crucial as healthcare organizations look for ways to stand out among competitors. The seven basic components of value for an integrated system, says Mr. Coddington, are improving quality of care, improving service, improving accessibility, reducing unit costs, increasing operating efficiency, strengthening customer ties and enhancing product offerings. In this issue, The Quality Letter reports on how several systems have used these seven components to increase patient and purchaser satisfaction.

  4. Time division multiple access for vehicular communications

    CERN Document Server

    Omar, Hassan Aboubakr

    2014-01-01

    This brief focuses on medium access control (MAC) in vehicular ad hoc networks (VANETs), and presents VeMAC, a novel MAC scheme based on distributed time division multiple access (TDMA) for VANETs. The performance of VeMAC is evaluated via mathematical analysis and computer simulations in comparison with other existing MAC protocols, including the IEEE 802.11p standard. This brief aims at proposing TDMA as a suitable MAC scheme for VANETs, which can support the quality-of-service requirements of high priority VANET applications.

  5. Desempenho e características de carcaça de bovinos mestiços de origem leiteira em condições de pastejo, restrito ou “ad libitum”, período das águas - DOI: 10.4025/actascianimsci.v28i2.655 Performance and carcass characteristics of dairy crossbreds bulls in grazing, restricted or “ad libitum”, during rainy season - DOI: 10.4025/actascianimsci.v28i2.655

    Directory of Open Access Journals (Sweden)

    Wilson Moreira Dutra Junior

    2006-01-01

    Full Text Available Este trabalho objetivou avaliar o desempenho e as características de carcaça de bovinos mestiços (5/8 Holandês/Zebu em pastejo de “Brachiaria decumbens” com acesso restrito ou “ad libitum”. Utilizaram-se 16 animais com idade e peso médios de 10 meses e 180 kg, respectivamente. Os animais foram distribuídos em delineamento de blocos casualizados, nos seguintes tratamentos: PAV = pastejo à vontade e PR = pastejo restrito (4 horas/dia. O período experimental teve duração de 114 dias. Observaram-se diferença entre os tratamentos (p The aim of this work was to evaluate the performance and carcass characteristic of crossbred bulls (5/8 holstein/zebu in grazing of “Brachiaria decumbens” with restrict access or "ad libitum". 16 animals with an average of age and live weight of 10 months and 180kg respectively were used. The animals were assigned in a randomized block design, according to the following treatments: “ad libitium” grazing (AG and restricted grazing (RG (4 hours/day. The experimental period lasted 114 days. There were statistical differences between the treatments (p < 0.05 on final live weight (FLW: 229.83 and 207.42 kg for unlimited grazing and restricted grazing, respectively, as well as for average daily gain (ADG: 0.618 and 0.230 kg. There were also statistical differences between the treatments (p < 0.05 to final empty body weight, daily empty body weight gain, hot and cold carcass weight, cold carcass yield (CCY/FLW and loin eye area according to the two methods used. The performance of the animals in restricted grazing had satisfactory results to the rainy season in pasture of Brachiaria decumbens. The methods to determine the loin eye area did not differ. However, the "plastic grid" is more recommended.

  6. Pro Access 2010 Development

    CERN Document Server

    Collins, Mark

    2011-01-01

    Pro Access 2010 Development is a fundamental resource for developing business applications that take advantage of the features of Access 2010 and the many sources of data available to your business. In this book, you'll learn how to build database applications, create Web-based databases, develop macros and Visual Basic for Applications (VBA) tools for Access applications, integrate Access with SharePoint and other business systems, and much more. Using a practical, hands-on approach, this book will take you through all the facets of developing Access-based solutions, such as data modeling, co

  7. Access 2013 for dummies

    CERN Document Server

    Ulrich Fuller, Laurie

    2013-01-01

    The easy guide to Microsoft Access returns with updates on the latest version! Microsoft Access allows you to store, organize, view, analyze, and share data; the new Access 2013 release enables you to build even more powerful, custom database solutions that integrate with the web and enterprise data sources. Access 2013 For Dummies covers all the new features of the latest version of Accessand serves as an ideal reference, combining the latest Access features with the basics of building usable databases. You'll learn how to create an app from the Welcome screen, get support

  8. Android Access Control Extension

    Directory of Open Access Journals (Sweden)

    Anton Baláž

    2015-12-01

    Full Text Available The main objective of this work is to analyze and extend security model of mobile devices running on Android OS. Provided security extension is a Linux kernel security module that allows the system administrator to restrict program's capabilities with per-program profiles. Profiles can allow capabilities like network access, raw socket access, and the permission to read, write, or execute files on matching paths. Module supplements the traditional Android capability access control model by providing mandatory access control (MAC based on path. This extension increases security of access to system objects in a device and allows creating security sandboxes per application.

  9. Beamspace Multiple Input Multiple Output. Part II: Steerable Antennas in Mobile Ad Hoc Networks

    Science.gov (United States)

    2016-09-01

    Networks with Beamforming Antennas.” Proceedings of the 2nd ACM International Symposium on Mobile Ad Hoc Networking & Computing (pp. 95–105). October...4–5, Long Beach, CA. ACM . 19. Choudhury, R. R., X. Yang, R. Ramanathan, and N. H. Vaidya. 2002. “Using Directional Antennas for Medium Access...Atlanta, GA. ACM . 20. Ramanathan, R., J. Redi, J., C. Santivanez, D. Wiggins, and S. Polit. 2005. “Ad Hoc Networking with Directional Antennas: A

  10. Protein domain organisation: adding order

    Directory of Open Access Journals (Sweden)

    Kummerfeld Sarah K

    2009-01-01

    Full Text Available Abstract Background Domains are the building blocks of proteins. During evolution, they have been duplicated, fused and recombined, to produce proteins with novel structures and functions. Structural and genome-scale studies have shown that pairs or groups of domains observed together in a protein are almost always found in only one N to C terminal order and are the result of a single recombination event that has been propagated by duplication of the multi-domain unit. Previous studies of domain organisation have used graph theory to represent the co-occurrence of domains within proteins. We build on this approach by adding directionality to the graphs and connecting nodes based on their relative order in the protein. Most of the time, the linear order of domains is conserved. However, using the directed graph representation we have identified non-linear features of domain organization that are over-represented in genomes. Recognising these patterns and unravelling how they have arisen may allow us to understand the functional relationships between domains and understand how the protein repertoire has evolved. Results We identify groups of domains that are not linearly conserved, but instead have been shuffled during evolution so that they occur in multiple different orders. We consider 192 genomes across all three kingdoms of life and use domain and protein annotation to understand their functional significance. To identify these features and assess their statistical significance, we represent the linear order of domains in proteins as a directed graph and apply graph theoretical methods. We describe two higher-order patterns of domain organisation: clusters and bi-directionally associated domain pairs and explore their functional importance and phylogenetic conservation. Conclusion Taking into account the order of domains, we have derived a novel picture of global protein organization. We found that all genomes have a higher than expected

  11. Urban Railway Accessibility

    Institute of Scientific and Technical Information of China (English)

    GUAN Hongzhi; YIN Yuanfei; YAN Hai; HAN Yan; QIN Huanmei

    2007-01-01

    Effective use of urban rapid railway systems requires that the railway systems be effectively connected with other transportation modes so that they are accessible. This paper uses the logit model and data to analyze the factors influencing railway access choices in a railway choice access model. The results indicate that access time, access cost, and access distance are factors significantly affecting railway access choices. The user's income significantly affects the probability of choosing to walk rather than to take a taxi,but is not related to choosing buses or bicycles. Vehicle ownership significantly affects the probability of choosing a taxi, but is not significantly related to the other modes. The conclusions provide an analysis tool for urban railway planning and construction.

  12. Open Access @ DTU

    DEFF Research Database (Denmark)

    Ekstrøm, Jeannette

    Open Access is high on the agenda in Denmark and internationally. Denmark has announced a national strategy for Open Access that aims to achieve Open Access to 80% in 2017 and 100% in 2022 to peer review research articles. All public Danish funders as well as H2020 requires that all peer review...... articles that is an outcome of their funding will be Open Access. Uploading your full texts (your final author manuscript after review ) to DTU Orbit is a fundamental part of providing Open Access to your research. We are here to answer all your questions with regards to Open Access and related topics...... such as copyright, DTU Orbit, Open Access journals, APCs, Vouchers etc....

  13. On Throughput Improvement of Wireless Ad Hoc Networks with Hidden Nodes

    Science.gov (United States)

    Choi, Hong-Seok; Lim, Jong-Tae

    In this letter, we present the throughput analysis of the wireless ad hoc networks based on the IEEE 802.11 MAC (Medium Access Control). Especially, our analysis includes the case with the hidden node problem so that it can be applied to the multi-hop networks. In addition, we suggest a new channel access control algorithm to maximize the network throughput and show the usefulness of the proposed algorithm through simulations.

  14. Flat Currents of Green-Schwarz Superstring in AdS2 × S2 Background

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    From the κ symmetric action of ⅡB string in AdS2 × S2 background given by Zhou, we derive the equations of motion. By using the twisted dual transformation which was introduced by Hou, we construct the flat currents, conserving non-local charge with one free parameter, for the superstring in AdS2 × S2.

  15. Joule-Thomson expansion of the charged AdS black holes

    Science.gov (United States)

    Ökcü, Özgür; Aydıner, Ekrem

    2017-01-01

    In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in the T- P plane and determine the cooling-heating regions.

  16. Joule-Thomson Expansion of Charged AdS Black Holes

    CERN Document Server

    Ökcü, Özgür

    2016-01-01

    In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in $T-P$ plane and determine the cooling-heating regions.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Herdeiro, Carlos A. R.; Radu, Eugen

    2016-11-01

    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.

  19. Effects of ad placement and type on consumer responses to podcast ads.

    Science.gov (United States)

    Ritter, Eric A; Cho, Chang-Hoan

    2009-10-01

    The purpose of this study was to understand the effects of podcast ad placement and podcast ad type on consumers' perceived intrusiveness, perceived irritation, attitude toward the ad, and ad avoidance. Our 2 x 2 (traditional ad vs. sponsorship by beginning vs. middle) experimental study found that sponsorships generated better consumer responses than did traditional ads and that podcast ads placed at the beginning of audio podcasts yielded better consumer responses than those placed in the middle. Implications for marketers and advertisers are discussed.

  20. AdS perturbations, isometries, selection rules and the Higgs oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium); Nivesvivat, Rongvoram [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand)

    2016-01-25

    Dynamics of small-amplitude perturbations in the global anti-de Sitter (AdS) spacetime is restricted by selection rules that forbid effective energy transfer between certain sets of normal modes. The selection rules arise algebraically because some integrals of products of AdS mode functions vanish. Here, we reveal the relation of these selection rules to AdS isometries. The formulation we discover through this systematic approach is both simpler and stronger than what has been reported previously. In addition to the selection rule considerations, we develop a number of useful representations for the global AdS mode functions, with connections to algebraic structures of the Higgs oscillator, a superintegrable system describing a particle on a sphere in an inverse cosine-squared potential, where the AdS isometries play the role of a spectrum-generating algebra.

  1. 77 FR 24646 - Open Access and Priority Rights on Interconnection Facilities

    Science.gov (United States)

    2012-04-25

    ... Energy Regulatory Commission 18 CFR Part 40 Open Access and Priority Rights on Interconnection Facilities... Inquiry, the Commission seeks comment on open access and priority rights for capacity on interconnection... ] 61,051 Docket Nos. Open Access and Priority Rights on Interconnection AD12-14-000 Facilities...

  2. ADS Services in support of the Discovery, Management and Evaluation of Science Data

    Science.gov (United States)

    Accomazzi, Alberto

    2015-12-01

    The NASA Astrophysics Data System (ADS) has long been used as a discovery platform for the scientific literature in Astronomy and Physics. With the addition of records describing datasets linked to publications, observing proposals and software used in refereed astronomy papers, the ADS is now increasingly used to find, access and cite an wider number of scientific resources. In this talk, I will discuss the recent efforts involving the indexing of software metadata, and our ongoing discussions with publishers in support of software and data citation. I will demonstrate the use of ADS's new services in support of discovery and evaluation of individual researchers as well as archival data products.

  3. Physical exercise protects against alzheimer's disease in 3xTg-AD mice

    OpenAIRE

    García-Mesa, Yoelvis; López-Ramos, Juan Carlos; Giménez-Llort, Lydia; Revilla, Susana; Guerra, Rafael; Gruart, Agnès; Frank M LaFerla; Cristòfol, Rosa; Delgado-García, José María; Sanfeliu, Coral

    2011-01-01

    Physical exercise is considered to exert a positive neurophysiological effect that helps to maintain normal brain activity in the elderly. Expectations that it could help to fight Alzheimer's disease (AD) were recently raised. This study analyzed the effects of different patterns of physical exercise on the 3xTg-AD mouse. Male and female 3xTg-AD mice at an early pathological stage (4-month-old) have had free access to a running wheel for 1 month, whereas mice at a moderate pathological stage(...

  4. CYBERSECURITY AND USER ACCOUNTABILITY IN THE C-AD CONTROL SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    MORRIS,J.T.; BINELLO, S.; D OTTAVIO, T.; KATZ, R.A.

    2007-10-15

    A heightened awareness of cybersecurity has led to a review of the procedures that ensure user accountability for actions performed on the computers of the Collider-Accelerator Department (C-AD) Control System. Control system consoles are shared by multiple users in control rooms throughout the C-AD complex. A significant challenge has been the establishment of procedures that securely control and monitor access to these shared consoles without impeding accelerator operations. This paper provides an overview of C-AD cybersecurity strategies with an emphasis on recent enhancements in user authentication and tracking methods.

  5. A Novel Approach for Attacks Mitigation in Mobile Ad Hoc Networks Using Cellular Automatas

    Directory of Open Access Journals (Sweden)

    Himadri Nath Saha

    2012-04-01

    Full Text Available Many security schemes for mobile ad-hoc network(MANET have been proposed so far but none of them has been successful in combating the different types of attacks that a mobile ad-hoc network often faces. This paper is providing one way of mitigating attacks in mobile ad-hoc networks by authenticating the node who tries to access this network .This scheme has been applied by using cellular automata (CA. Our simulation results show how cellular automata(CA is implemented for user authentication and secure transmission in MANET.

  6. Perceived threat of Alzheimer disease (AD): the role of personal experience with AD.

    Science.gov (United States)

    Suhr, Julie A; Kinkela, Jessica H

    2007-01-01

    The fear of developing Alzheimer disease (AD) is highly salient, particularly for biologic family members. The current study evaluated social/cognitive explanations for perceived AD threat beyond genetic relatedness, including personal experience with AD, belief in negative aging stereotypes, and performance on delayed memory tasks. Participants were 97 healthy older adults aged 50 to 85, self-referred for a free community memory screen. Results showed that, as expected, personal AD experience was related to perceived AD threat. Furthermore, consistent with expectations, AD experience moderated the relationship between perceived AD threat and other explanatory variables, including age, belief in negative aging stereotypes, and cognitive performance. In those with AD experience, whether genetic or not, younger age was associated with more perceived AD threat, but an inverse relationship was seen in those without AD experience. Those with genetic AD experience seem particularly vulnerable to the effects of negative age stereotype beliefs on perceived AD threat, and show an inverse relationship between their actual cognitive performance and their perception of personal AD threat. Results highlight the importance of considering personal experience with AD when assessing a person's self-reported concerns about AD or his/her own memory changes.

  7. Exploring antismoking ads: appeals, themes, and consequences.

    Science.gov (United States)

    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.

  8. Simulation study for Mobile Ad hoc Networks Using DMAC Protocol

    Directory of Open Access Journals (Sweden)

    Vikas Sejwar

    2012-01-01

    Full Text Available This paper addresses the issue of deafness problem in Mobile Ad Hoc Networks (MANETs using directional antennas. Directional antennas arebeneficial for wireless ad hoc networks consisting of a collection of wireless hosts. A suitable Medium Access Control (MAC protocol must be designed to best utilize directional antennas. Deafness is caused whentwo nodes are in ongoing transmission and a third node (Deaf Node wants to communicate with one of that node. But it get no response because transmission of two nodes are in process. Though directional antennas offer better spatial reuse, but this problem can have a serious impact on network performance. A New DMAC (Directional Medium Access Control protocol uses flags in DNAV (Directional Network Allocation Vector tables to maintain information regarding the transmissionbetween the nodes in the network and their neighbor’s location. Two performance matrices have been used to show the impact of New DMAC algorithm on Deafness problem using simulator. These are RTS Failure Ratio and RTS Retransmission due to timeout

  9. Port Access Cardiac Surgery.

    Science.gov (United States)

    Viganó, Mario; Minzioni, Gaetano; Spreafico, Patrizio; Rinaldi, Mauro; Pasquino, Stefano; Ceriana, Piero; Locatelli, Alessandro

    2000-10-01

    The port-access technique for cardiac surgery was recently developed at Stanford University in California as a less invasive method to perform some cardiac operations. The port-access system has been described in detail elsewhere. It is based on femoral arterial and venous access for cardiopulmonary bypass (CPB) and on the adoption of a specially designed triple-lumen catheter described originally by Peters, and subsequently modified and developed in the definitive configuration called the endoaortic clamp.

  10. Are PDF Documents Accessible?

    Directory of Open Access Journals (Sweden)

    Mireia Ribera Turró

    2008-09-01

    Full Text Available Adobe PDF is one of the most widely used formats in scientific communications and in administrative documents. In its latest versions it has incorporated structural tags and improvements that increase its level of accessibility. This article reviews the concept of accessibility in the reading of digital documents and evaluates the accessibility of PDF according to the most widely established standards.

  11. Access Data Analysis Cookbook

    CERN Document Server

    Bluttman, Ken

    2008-01-01

    This book offers practical recipes to solve a variety of common problems that users have with extracting Access data and performing calculations on it. Whether you use Access 2007 or an earlier version, this book will teach you new methods to query data, different ways to move data in and out of Access, how to calculate answers to financial and investment issues, how to jump beyond SQL by manipulating data with VBA, and more.

  12. Accessible e-learning

    OpenAIRE

    Bühler, Christian; Scheer, Birgit

    2005-01-01

    People with disabilities often encounter difficulties while trying to learn something, because teaching material is for example not accessible to blind people or rooms, where courses take place, are not accessible to people using a wheelchair. E-learning provides an opportunity to disabled people. With the new German law on the equalisation of opportunities for people with disabilities for the first time access to information technology was explicitly taken up in German legislation. As a cons...

  13. An Efficient Quality of Service Based Routing Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Tapan Kumar Godder

    2011-05-01

    Full Text Available Ad-hoc network is set up with multiple wireless devices without any infrastructure. Its employment is favored in many environments. Quality of Service (QoS is one of the main issues for any network and due to bandwidth constraint and dynamic topology of mobile ad hoc networks, supporting Quality of Service (QoS is extremely a challenging task. It is modeled as a multi-layer problem and is considered in both Medium Access Control (MAC and routing layers for ad hoc networks. Ad-hoc On-demand Distance Vector (AODV routing protocol is one of the most used and popular reactive routing protocols in ad-hoc networks. This paper proposed a new protocol QoS based AODV (QAODV which is a modified version of AODV.

  14. OGIS Access System

    Data.gov (United States)

    National Archives and Records Administration — The OGIS Access System (OAS) provides case management, stakeholder collaboration, and public communications activities including a web presence via a web portal.

  15. Open Access Policy

    OpenAIRE

    University of East London, .

    2013-01-01

    The University of East London is committed to and supports open access to its research publications.\\ud There is a worldwide move towards free and unrestricted access to research publications, with benefits\\ud for researchers, universities and wider society. UEL supports this initiative and recognises the\\ud importance of open access in increasing the visibility and impact of research. This policy is aligned with\\ud and supports HEFCE’s Policy for Open Access in the Post‐2014 REF, and is alig...

  16. Channel Access in Erlang

    Energy Technology Data Exchange (ETDEWEB)

    Nicklaus, Dennis J. [Fermilab

    2013-10-13

    We have developed an Erlang language implementation of the Channel Access protocol. Included are low-level functions for encoding and decoding Channel Access protocol network packets as well as higher level functions for monitoring or setting EPICS process variables. This provides access to EPICS process variables for the Fermilab Acnet control system via our Erlang-based front-end architecture without having to interface to C/C++ programs and libraries. Erlang is a functional programming language originally developed for real-time telecommunications applications. Its network programming features and list management functions make it particularly well-suited for the task of managing multiple Channel Access circuits and PV monitors.

  17. Web Accessibility and Guidelines

    Science.gov (United States)

    Harper, Simon; Yesilada, Yeliz

    Access to, and movement around, complex online environments, of which the World Wide Web (Web) is the most popular example, has long been considered an important and major issue in the Web design and usability field. The commonly used slang phrase ‘surfing the Web’ implies rapid and free access, pointing to its importance among designers and users alike. It has also been long established that this potentially complex and difficult access is further complicated, and becomes neither rapid nor free, if the user is disabled. There are millions of people who have disabilities that affect their use of the Web. Web accessibility aims to help these people to perceive, understand, navigate, and interact with, as well as contribute to, the Web, and thereby the society in general. This accessibility is, in part, facilitated by the Web Content Accessibility Guidelines (WCAG) currently moving from version one to two. These guidelines are intended to encourage designers to make sure their sites conform to specifications, and in that conformance enable the assistive technologies of disabled users to better interact with the page content. In this way, it was hoped that accessibility could be supported. While this is in part true, guidelines do not solve all problems and the new WCAG version two guidelines are surrounded by controversy and intrigue. This chapter aims to establish the published literature related to Web accessibility and Web accessibility guidelines, and discuss limitations of the current guidelines and future directions.

  18. Access 2013 bible

    CERN Document Server

    Alexander, Michael

    2013-01-01

    A comprehensive reference to the updated and new features of Access 2013 As the world's most popular database management tool, Access enables you to organize, present, analyze, and share data as well as build powerful database solutions. However, databases can be complex. That's why you need the expert guidance in this comprehensive reference. Access 2013 Bible helps you gain a solid understanding of database purpose, construction, and application so that whether you're new to Access or looking to upgrade to the 2013 version, this well-rounded resource provides you with a th

  19. Adding image search capabilities to astronomical archives

    Science.gov (United States)

    Baumann, Peter; Bruggen, Marcus

    VO-Paris Data Centre is a common structure to the Observatory of Paris, in charge of develop-ing Virtual Observatory activities. As a partner in Europlanet-IDIS, VO-Paris contributes to defining the future European VO in Planetary Science. There are two aspects in this program: on one hand, VO-Paris is in charge of the IDIS thematic node "Planetary Dynamics and Extra-Terrestrial Matter", which distributes data resources related to this field, including resources developed by other Europlanet Work Packages. On the other hand, OV-Paris is a partner in the Joint Research Activity (JRA4) which designs the VO infrastructure, and is the co-leader of the task "Added Value Services". VO-Paris baseline in Europlanet-IDIS is to remain as compatible as possible with existing VO systems in Astronomy and Solar Physics, ie to use standards and protocols developed in the IVOA context when they suit the need of Planetary Science, and possibly to propose their extensions whenever the existing standards do not address the usual specific questions in Planetary Science. This approach will allow the rapid design of a registry system, and easy use of tools providing basic functions such as data visualization. Concerning the data resources involved, our aim is to set up a core of data services on which the community will accrete new data resources accessible through VO protocols. This initial core is currently expected to include AMDA (CDPP's service in plasma physics), SSODnet (a semi-VO service being developed at OV-Paris), the PSA (ESA's space missions archive), GhoSST (solid samples spectroscopy developed at LPG), and various topical data bases such as a reference data base set up in LESIA to support the Herschel TNO key-program. The OV-Paris IDIS node can be reached at: http://voparis-europlanet.obspm.fr/ The EuroPlaNet RI project is funded by the European Commission under the 7th Framework Program, grant 228319 "Capacities Specific Programme".

  20. From path integrals to tensor networks for the AdS /CFT correspondence

    Science.gov (United States)

    Miyaji, Masamichi; Takayanagi, Tadashi; Watanabe, Kento

    2017-03-01

    In this paper, we discuss tensor network descriptions of AdS /CFT from two different viewpoints. First, we start with a Euclidean path-integral computation of ground state wave functions with a UV cutoff. We consider its efficient optimization by making its UV cutoff position dependent and define a quantum state at each length scale. We conjecture that this path integral corresponds to a time slice of anti-de Sitter (AdS) spacetime. Next, we derive a flow of quantum states by rewriting the action of Killing vectors of AdS3 in terms of the dual two-dimensional conformal field theory (CFT). Both approaches support a correspondence between the hyperbolic time slice H2 in AdS3 and a version of continuous multiscale entanglement renormalization ansatz. We also give a heuristic argument about why we can expect a sub-AdS scale bulk locality for holographic CFTs.

  1. Distributed optimization of a multisubchannel Ad Hoc cognitive radio network

    KAUST Repository

    Leith, Alex

    2012-05-01

    In this paper, we study the distributed-duality-based optimization of a multisubchannel ad hoc cognitive radio network (CRN) that coexists with a multicell primary radio network (PRN). For radio resource allocation in multiuser orthogonal frequency-division multiplexing (MU-OFDM) systems, the orthogonal-access-based exclusive subchannel assignment (ESA) technique has been a popular method, but it is suboptimal in ad hoc networks, because nonorthogonal access between multiple secondary-user links by using shared subchannel assignment (SSA) can bring a higher weighted sum rate. We utilize the Lagrangian dual composition tool and design low-complexity near-optimal SSA resource allocation methods, assuming practical discrete-rate modulation and that the CRN-to-PRN interference constraint has to strictly be satisfied. However, available SSA methods for CRNs are either suboptimal or involve high complexity and suffer from slow convergence. To address this problem, we design fast-convergence SSA duality schemes and introduce several novel methods to increase the speed of convergence and to satisfy various system constraints with low complexity. For practical implementation in ad hoc CRNs, we design distributed-duality schemes that involve only a small number of CRN local information exchanges for dual update. The effects of many system parameters are presented through simulation results, which show that the near-optimal SSA duality scheme can perform significantly better than the suboptimal ESA duality and SSA-iterative waterfilling schemes and that the performance loss of the distributed schemes is small, compared with their centralized counterparts. © 2012 IEEE.

  2. Identity And Access Management e Federazione

    Directory of Open Access Journals (Sweden)

    Virginia Calabritto

    2012-07-01

    Full Text Available ItLa rete telematica è in costante crescita e così i servizi online che, in modo sempre più penetrante, rappresentano un aspetto della nostra quotidianità. I servizi in rete si distinguono in servizi ad accesso libero e servizi ad accesso controllato. Ogni giorno studenti, ricercatori e docenti accedono a contenuti e servizi (risorse ad accesso controllato con modalità diverse, la più diffusa è l'utilizzo dell‘informazione utenza/password, informazione diversa per ciascuna risorsa. Da questo punto di vista l’ampia disponibilità di risorse in rete crea all’utente, ma non solo a lui, diversi problemi, non ultimo quello della memorizzazione di un numero sempre più ampio di coppie utenza/password.L’articolo è teso ad illustrare, nel dettaglio, scenario e problematiche per passare quindi ad accennare alle tecnologie che possono costituire una soluzione, ovvero, l'Identity Management, il Single Sign On e le federazioni di infrastrutture di autenticazione e autorizzazione e, quindi, a degli esempi tra cui IDEM, la prima federazione italiana di Infrastrutture di Autenticazione e Autorizzazione, che coinvolge gli enti della comunità scientifica ed accademica e i fornitori di servizi.EnThe Internet is constantly growing, therefore on-line services, are becoming part of our daily life in a more and more pervasive manner. The network services are divided into two types of access: free access and controlled access. Every day students, researchers and teachers access content and services (resources through controlled access using different modes, e.g using user / password information which is different for each resource. From this perspective, the large availability of networked resources generates many problems for the users, last but not least the inconvenience of storing an increasing number of user / password.The article aims to illustrate, in detail, the context and the problems related to the management of a digital identiy in the

  3. Value added meat marketing around the globe

    DEFF Research Database (Denmark)

    Grebitus, Carola; Mueller Loose, Simone

    In highly competitive meat markets it is important to offer value added products to consumers. Thus, we need to understand which attributes are especially valued by consumers. This track session will contribute to a better understanding of consumer preferences for value added meats across differe...

  4. Status Report on the Antiproton Decelerator (AD)

    CERN Document Server

    Erikson, T; Möhl, D

    2001-01-01

    CERN's new Antiproton Decelerator (AD) has been delivering a 100 MeV/c antiproton beam to three experiments (ASACUSA, AHENA and ATRAP) since July 10th, 2000. In this status report, we summarise the initial performance of the AD, draw provisional conclusions from the first month of operation and finally give some prospects for the future.

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

    Science.gov (United States)

    Banerjee, Aritra; Panigrahi, Kamal L.

    2016-09-01

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

  6. On circular strings in $(AdS_3 \\times S^3)_{\\varkappa}$

    CERN Document Server

    Banerjee, Aritra

    2016-01-01

    The so called one-parameter (often called $\\varkappa$) deformed $AdS$ string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the $(AdS_3 \\times S^3)_{\\varkappa}$ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the $\\varkappa$-deformed $AdS_3$ and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.

  7. Various types of phase transitions in the AdS soliton background

    CERN Document Server

    Peng, Yan; Wang, Bin

    2011-01-01

    We study the basic holographic insulator and superconductor phase transition in the AdS soliton background by generalizing the spontaneous breaking of a global U(1) symmetry to occur via St$\\ddot{u}$ckelberg mechanism. We construct the soliton solutions with backreaction and examine the effects of the backreaction on the condensation of the scalar hair in the generalized St$\\ddot{u}$ckelberg Lagrangian. We disclose rich physics in various phase transitions. In addition to the AdS soliton configuration, we also examine the property of the phase transition in the AdS black hole background.

  8. Thermodynamic geometry and phase transitions of AdS braneworld black holes

    Science.gov (United States)

    Chaturvedi, Pankaj; Sengupta, Gautam

    2017-02-01

    The thermodynamics and phase transitions of charged RN-AdS and rotating Kerr-AdS black holes in a generalized Randall-Sundrum braneworld are investigated in the framework of thermodynamic geometry. A detailed analysis of the thermodynamics, stability and phase structures in the canonical and the grand canonical ensembles for these AdS braneworld black holes are described. The thermodynamic curvatures for both these AdS braneworld black holes are computed and studied as a function of the thermodynamic variables. Through this analysis we illustrate an interesting dependence of the phase structures on the braneworld parameter for these black holes.

  9. Google Advertising Tools Cashing in with AdSense and AdWords

    CERN Document Server

    Davis, Harold

    2010-01-01

    With this book, you'll learn how to take full advantage of Google AdWords and AdSense, the sophisticated online advertising tools used by thousands of large and small businesses. This new edition provides a substantially updated guide to advertising on the Web, including how it works in general, and how Google's advertising programs in particular help you make money. You'll find everything you need to work with AdWords, which lets you generate text ads to accompany specific search term results, and AdSense, which automatically delivers precisely targeted text and image ads to your website.

  10. Entropy of Warped Taub-NUT AdS Black String via the Brick Wall Method

    CERN Document Server

    Lee, Chong Oh

    2014-01-01

    When we consider five-dimensional warped Taub-NUT AdS black string with minimally coupled massive scalar field, we calculate an entropy by using the brick wall method. In extremely light effective mass, we find the entropy is proportional to an extra dimension wave number as well as quadratically divergent in a cutoff parameter. After taking zero NUT charge, we find the entropy of warped (AdS) Schwartzshield black hole string has a similar properties in as warped Taub-NUT AdS black string.

  11. Holographic complexity and fidelity susceptibility as holographic information dual to different volumes in AdS

    Directory of Open Access Journals (Sweden)

    N.S. Mazhari

    2017-03-01

    Full Text Available The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.

  12. Beyond the unitarity bound in AdS/CFT{sub (A)dS}

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Tomas [University of California, Santa Barbara (United States); Uhlemann, Christoph [Universitaet Wuerzburg (Germany)

    2012-07-01

    We study CFTs on dS and AdS spacetimes from a holographic perspective, in particular how the unitarity properties of the boundary theory are reflected in the bulk description. On geometries with an (A)dS conformal boundary we choose mass and boundary conditions for a Klein-Gordon field such that the corresponding CFT operator violates the unitarity bound. We analyze how the non-unitarity is reproduced in the bulk and discuss, for the case of an AdS boundary, prospects for multi-layered AdS/CFT-type dualities.

  13. Phase Transition and Clapeyon Equation of Black Hole in Higher Dimensional AdS Spacetime

    CERN Document Server

    Zhao, Hui-Hua; Ma, Meng-Sen; Zhao, Ren

    2014-01-01

    By Maxwell equal area law we study the phase transition in higher dimensional Anti-de Sitter (AdS) Reissner-Nordstr\\"{o}m (RN) black hole and Kerr black hole in this paper. The coexisting region of the two phases involved in the phase transition is found and the coexisting curves are shown in $P-T$ figures. We also analytically investigate the parameters which affect the coexisting curves. To better compare with ordinary thermodynamic systems, the Clapeyon equation is derived for higher dimensional AdS black holes. This paper can help to deepen the understanding of the phase transition and phase structure of AdS black holes.

  14. Boundary action of free AdS higher-spin gauge fields and the holographic correspondence

    CERN Document Server

    Joung, Euihun

    2011-01-01

    We determine the boundary terms of the free higher-spin action which reproduce the AdS Fronsdal equations in an AdS manifold with a finite distance boundary. The boundary terms are further constrained by the gauge invariance of the total action. We show that, for spins larger than two, no local boundary term can restore the full gauge symmetry, and the broken symmetry corresponds to higher-spin Weyl transformations on the boundary CFT. The boundary action is used for the evaluation of the on-shell higher-spin AdS action in terms of the boundary data given by a conformal higher-spin field.

  15. Geometric Finiteness, Holography and Quasinormal Modes for the Warped AdS_3 Black Hole

    CERN Document Server

    Gupta, Kumar S; Sen, Siddhartha; Sivakumar, M

    2009-01-01

    We show that there exists a precise kinematical notion of holography for the Euclidean warped $AdS_3$ black hole. This follows from the fact that the Euclidean warped $AdS_3$ black hole spacetime is a geometrically finite hyperbolic manifold. For such manifolds a theorem of Sullivan provides a one-to-one correspondence between the hyperbolic structure in the bulk and the conformal structure of its boundary. Using this theorem we obtain the holographic quasinormal modes for the warped $AdS_3$ black hole.

  16. An improved AFS phase for AdS3 string integrability

    CERN Document Server

    Abbott, Michael C

    2015-01-01

    We propose a number of modifications to the classical term in the dressing phase for integrable strings in AdS3 x S3 x S3 x S1, and check these against existing perturbative calculations, crossing symmetry, and the semiclassical limit of the Bethe equations. The principal change is that the phase for different masses should start with a term Q_1 Q_2, like the one-loop AdS3 dressing phase, rather than Q_2 Q_3 as for the original AdS5 AFS phase.

  17. Holographic Complexity and Fidelity Susceptibility as Holographic Information Dual to Different Volumes in AdS

    CERN Document Server

    Mazhari, N S; Bahamonde, Sebastian; Faizal, Mir; Myrzakulov, Ratbay

    2016-01-01

    The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution and a solution with cylindrically symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not any such dependence.

  18. [Rapid analysis of added ingredients in heroin].

    Science.gov (United States)

    Wang, Ji-fen; Yu, Jing; Guo, Xin; Sun, Xing-long; Wang, Ding-fang

    2011-07-01

    The method of rapid analysis of added ingredients in heroin was studied in the present paper. Adding sucrose, fructose, glucose, starch, caffeine and phenacetin to heroin with a certain percentage, the changes in the infrared spectrum with the concentration of heroin increasing and the detection limit of the additives were determined. Whether or not heroin can be detected in the sample with high concentration of added ingredients was studied using Raman spectroscopy. Similarly, in high purity of heroin, whether or not Raman spectroscopy can detect the added ingredients was tested. Through systematic experiments, the results showed that: using infrared spectroscopy and Raman spectroscopy to test the added ingredients of heroin is a rapid and effective method. Each has both advantages and disadvantages. We should select the appropriate method according to the actual cases.

  19. The concept of added value of FM

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: This chapter presents research perspectives and theoretical reflections on the concept of added value of FM from a variety of academic fields. Methodology: A literature review of the most influential journals within the academic fields of Facilities Management (FM), Corporate Real Estate...... conceptualization of the concept of added value of FM is of utmost importance for further research into the added value of FM and well-considered, evidence- based Value Adding Management in practice. Research limitations: Due to limited time not all FM-related journals could be included in the literature review...... Management (CREM) and Business to Business Marketing (B2B Marketing). Findings: The research shows different definitions and focus points, dependent on the academic field and the area of application. The different research perspectives explored a holistic view on the added value of FM by the integration...

  20. MedlinePlus: Accessibility

    Science.gov (United States)

    ... Tools Español You Are Here: Home → MedlinePlus Accessibility URL of this page: https://medlineplus.gov/accessibility.html ... or (301) 594-5983 and provide the address (URL) of the page on which you need assistance, ...

  1. Towards Accessible Search Systems

    NARCIS (Netherlands)

    Serdyukov, Pavel; Hiemstra, Djoerd; Ruthven, Ian

    2010-01-01

    The SIGIR workshop Towards Accessible Search Systems was the first workshop in the field to raise the discussion on how to make search engines accessible for different types of users. We report on the results of the workshop that was held on 23 July 2010 in conjunction with the 33rd Annual ACM SIGIR

  2. ACCESS Pointing Control System

    Science.gov (United States)

    Brugarolas, Paul; Alexander, James; Trauger, John; Moody, Dwight; Egerman, Robert; Vallone, Phillip; Elias, Jason; Hejal, Reem; Camelo, Vanessa; Bronowicki, Allen; O'Connor, David; Partrick, Richard; Orzechowski, Pawel; Spitter, Connie; Lillie, Chuck

    2010-01-01

    ACCESS (Actively-Corrected Coronograph for Exoplanet System Studies) was one of four medium-class exoplanet concepts selected for the NASA Astrophysics Strategic Mission Concept Study (ASMCS) program in 2008/2009. The ACCESS study evaluated four major coronograph concepts under a common space observatory. This paper describes the high precision pointing control system (PCS) baselined for this observatory.

  3. Demystifying Open Access

    Energy Technology Data Exchange (ETDEWEB)

    Mele, Salvatore (CERN)

    2007-05-30

    The tenets of Open Access are to grant anyone, anywhere and anytime free access to the results of scientific research. HEP spearheaded the Open Access dissemination of scientific results with the mass mailing of preprints in the pre-WWW era and with the launch of the arXiv preprint system at the dawn of the '90s. The HEP community is now ready for a further push to Open Access which retains all the advantages of the peer-review system and, at the same time, brings the spiraling cost of journal subscriptions under control. I will present a possible plan for the conversion to Open Access of HEP peer-reviewed journals, through a consortium of HEP funding agencies, laboratories and libraries: SCOAP3 (Sponsoring Consortium for Open Access Publishing in Particle Physics). SCOAP3 will engage with scientific publishers towards building a sustainable model for Open Access publishing, which is as transparent as possible for HEP authors. In this talk I will present a short overview of the history of Open Access in HEP, the details of the SCOAP3 model and the outlook for its implementation.

  4. ATLAS Data Access Policy

    CERN Document Server

    The ATLAS collaboration

    2015-01-01

    ATLAS has fully supported the principle of open access in its publication policy. This document outlines the policy of ATLAS as regards open access to data at different levels as described in the DPHEP model. The main objective is to make the data available in a usable way to people external to the ATLAS collaboration.

  5. Open Access policy effectiveness

    OpenAIRE

    Swan, Alma

    2015-01-01

    This presentation discusses the policy elements that are necessary for an effective open access policy, according to the findings of the analysis of the revamped ROARMAP tool for open access policies by PASTEUR4OA. It contains graphs, charts and numbers for evidence-based arguments

  6. Intellectual Access to Images.

    Science.gov (United States)

    Chen, Hsin-Liang; Rasmussen, Edie M.

    1999-01-01

    The increased availability of digital images is accompanied by a need for solutions to the problems inherent in indexing them for retrieval. Problems in image description and access are discussed, with a perspective on traditional and new solutions. Recent developments in intellectual access to images are surveyed and contrasted with…

  7. Comparing Information Access Approaches.

    Science.gov (United States)

    Chalmers, Matthew

    1999-01-01

    Presents a broad view of information access, drawing from philosophy and semiology in constructing a framework for comparative discussion that is used to examine the information representations that underlie four approaches to information access--information retrieval, workflow, collaborative filtering, and the path model. Contains 32 references.…

  8. Market Access and Welfare

    DEFF Research Database (Denmark)

    Raimondos-Møller, Pascalis; Woodland, Alan D.

    2015-01-01

    Well known tariff reform rules that are guaranteed to increase welfare will not necessarily increase market access, while rules that are guaranteed to increase market access will not necessarily increase welfare. The present paper proposes a new set of tariff reforms that can achieve both...

  9. Inflation in AdS/CFT

    Energy Technology Data Exchange (ETDEWEB)

    Freivogel, Ben; /Stanford U., Phys. Dept. /LBL, Berkeley; Hubeny, Veronika E.; /LBL, Berkeley /Durham U., Dept. of Math.; Maloney, Alexander; /Stanford U., Phys. Dept.; Myers, Rob; /Perimeter Inst. Theor. Phys. /Waterloo U.; Rangamani, Mukund; /LBL, Berkeley /Durham U., Dept. of Math.; Shenker, Stephen; /Stanford U., Phys. Dept.

    2005-10-07

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

  10. Public Access Defibrillation

    DEFF Research Database (Denmark)

    Agerskov, Marianne; Nielsen, Anne Møller; Hansen, Carolina Malta

    2015-01-01

    of OHCA-cases where an accessible AED was located within 100 m. In addition, we assessed 30-day survival. METHODS: Using data from the Mobile Emergency Care Unit and the Danish Cardiac Arrest Registry, we identified 521 patients with OHCA between October 1, 2011 and September 31, 2013 in Copenhagen......, Denmark. RESULTS: An AED was applied in 20 cases (3.8%, 95% CI [2.4 to 5.9]). Irrespective of AED accessibility, an AED was located within 100 m of a cardiac arrest in 23.4% (n=102, 95% CI [19.5 to 27.7]) of all OHCAs. However, at the time of OHCA, an AED was located within 100 m and accessible in only 15...... to ambulance arrival, but 15.1% of all OHCAs occurred within 100 m of an accessible AED. This indicates the potential of utilising AED networks by improving strategies for AED accessibility and referring bystanders of OHCA to existing AEDs....

  11. The Open Access Divide

    Directory of Open Access Journals (Sweden)

    Jingfeng Xia

    2013-10-01

    Full Text Available This paper is an attempt to review various aspects of the open access divide regarding the difference between those academics who support free sharing of data and scholarly output and those academics who do not. It provides a structured description by adopting the Ws doctrines emphasizing such questions as who, what, when, where and why for information-gathering. Using measurable variables to define a common expression of the open access divide, this study collects aggregated data from existing open access as well as non-open access publications including journal articles and extensive reports. The definition of the open access divide is integrated into the discussion of scholarship on a larger scale.

  12. Coded Random Access

    DEFF Research Database (Denmark)

    Paolini, Enrico; Stefanovic, Cedomir; Liva, Gianluigi

    2015-01-01

    , in which the structure of the access protocol can be mapped to a structure of an erasure-correcting code defined on graph. This opens the possibility to use coding theory and tools for designing efficient random access protocols, offering markedly better performance than ALOHA. Several instances of coded......The rise of machine-to-machine communications has rekindled the interest in random access protocols as a support for a massive number of uncoordinatedly transmitting devices. The legacy ALOHA approach is developed under a collision model, where slots containing collided packets are considered...... as waste. However, if the common receiver (e.g., base station) is capable to store the collision slots and use them in a transmission recovery process based on successive interference cancellation, the design space for access protocols is radically expanded. We present the paradigm of coded random access...

  13. Wi-Fi Networks Security and Accessing Control

    Directory of Open Access Journals (Sweden)

    Tarek S. Sobh

    2013-06-01

    Full Text Available As wireless networks access gains popularity in corporate, private and personal networks, the nature of wireless networks opens up new possibilities for network attacks. This paper negotiating Wi-Fi security against scanning of rogue Wi-Fi networks and other related activities and considers the monitoring of Wi-Fi traffic effects. The unauthorized access point (AP problem has raised more attention and resulted in obtaining wireless access without subscriber permission.This work assumes Wi-Fi AP under attack specially rogue AP and/or ad-hoc client. It provides a solution for detecting and preventing this attack. In addition, it provides the required user permissions to allow/block access of the files on the user of ad-hoc client. The experiments include the rogue AP attack are maintained and the effectiveness of the proposed solution are tested.

  14. A Grassmann Path From AdS$_3$ to Flat Space

    CERN Document Server

    Krishnan, Chethan; Roy, Shubho

    2013-01-01

    We show that interpreting the inverse AdS$_3$ radius $1/l$ as a Grassmann variable results in a formal map from gravity in AdS$_3$ to gravity in flat space. The underlying reason for this is the fact that $ISO(2,1)$ is the Inonu-Wigner contraction of $SO(2,2)$. We show how this works for the Chern-Simons actions, demonstrate how the general (Banados) solution in AdS$_3$ maps to the general flat space solution, and how the Killing vectors, charges and the Virasoro algebra in the Brown-Henneaux case map to the corresponding quantities in the BMS$_3$ case. Our results straightforwardly generalize to the higher spin case: the recently constructed flat space higher spin theories emerge automatically in this approach from their AdS counterparts. We conclude with a discussion of singularity resolution in the BMS gauge as an application.

  15. Quantum corrections to supergravity on AdS2×S2

    Science.gov (United States)

    Larsen, Finn; Lisbão, Pedro

    2015-04-01

    We compute the off-shell spectrum of supergravity on AdS2×S2 by explicit diagonalization of the equations of motion for an effective AdS2 theory where all fields are dualized to scalars and spin-1/2 fermions. We classify all bulk modes as physical, gauge violating, and pure gauge then compute the physical spectrum by explicit cancellation of unphysical modes. We identify boundary modes as physical fields on S2 that are formally pure gauge but with gauge function that is non-normalizable on AdS2. As an application we compute the leading quantum correction to AdS2×S2 as a sum over physical fields including boundary states. The result agrees with a previous computation by Sen [1] where unphysical modes were canceled by ghosts.

  16. Impaired cognition in depression and Alzheimer (AD: a gradient from depression to depression in AD

    Directory of Open Access Journals (Sweden)

    Narahyana Bom de Araujo

    2014-09-01

    Full Text Available Objective To assess cognition in major depressed (MD, Alzheimer's disease (AD, and depression in AD elderly. Method Subjects were evaluated by Mini Mental, Rey Auditory Verbal Learning Test, Rey Complex Figure, Digit Span, Similarities, Trail Making A/B, Verbal Fluency and Stroop. One-way ANOVA and multivariate models were used to compare the performance of each group on neuropsychological tests. Results We evaluated 212 subjects. Compared to MD, attention, working memory, processing speed and recall showed significantly better in controls. Controls showed significantly higher performance in all cognitive measures, except in attention compared to AD. Verbal fluency, memory, processing speed and abstract reasoning in MD was significantly higher compared to AD. AD was significantly better in general cognitive state than depression in AD. All other cognitive domains were similar. Conclusion A decreasing gradient in cognition appeared from the control to depression in AD, with MD and AD in an intermediate position.

  17. Study of ADS-B Data Evaluation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun; LIU Wei; ZHU Yanbo

    2011-01-01

    In western China,the terrain and meteorological conditions are so complex that it is not suitable to construct new radar stations.Automatic dependent surveillance-broadcast(ADS-B) is a totally new surveillance method,so before practically applied and operated in China,abundant tests and evaluations are necessary to validate the performance of ADS-B and guarantee the operational security.During the flight tests,we collect the data of radar,ADS-B and high accuracy position and compare the performance of ADS-B with radar based on high accuracy position.To solve the asynchronous problem among radar data,ADS-B data and real-time kinematic(RTK) data caused by different update rates,this article proposes the technique of synchronizing multi-surveil- lance data by extrapolating from the data of low update rate to high update rate according to velocity and heading.Meanwhile,because radar data,ADS-B data and RTK data are expressed in different coordinates and cannot be compared each other,this article provides a method to unifying the coordinates of multi-surveillance data.By the analysis and evaluation,we can conclude that the performance of ADS-B is better than radar.

  18. Supergravity background of the lambda-deformed AdS_3 x S^3 supercoset

    CERN Document Server

    Chervonyi, Yuri

    2016-01-01

    We construct the solution of type IIB supergravity describing the integrable lambda-deformation of the AdS_3 x S^3 supercoset. While the geometry corresponding to the deformation of the bosonic coset has been found in the past, our background is more natural for studying superstrings, and several interesting features distinguish our solution from its bosonic counterpart. We also report progress towards constructing the lambda-deformation of the AdS_5 x S^5 supercoset.

  19. Ad Hoc Network Securing Policy%Ad hoc网络安全策略

    Institute of Scientific and Technical Information of China (English)

    刘志远; 张曼曼

    2006-01-01

    本文首先介绍了Ad hoc网络的产生、定义、特点和应用,然后在探讨Ad hoc网络的安全需求的基础上,着重分析了移动Ad hoc网络易于遭受的攻击,最后讨论并提出了Ad Hoc网络的一些安全策略.

  20. Yangian of AdS_3/CFT_2 and its deformation

    CERN Document Server

    Regelskis, Vidas

    2015-01-01

    We construct highest-weight modules and a Yangian extension of the centrally extended superalgebra appearing in the worldsheet scattering associated with the AdS_3 /CFT_2 duality, and show a link to the Yangian of AdS_5/CFT_4. We also consider a quantum deformation of this superalgebra, its modules and a quantum affine extension of the Drinfeld-Jimbo type which describes deformed worldsheet scattering.