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https://www.readbyqxmd.com/read/28194789/behavioral-effects-of-delayed-timeouts-from-reinforcement
#1
Tom Byrne, Alan Poling
Timeouts are sometimes used in applied settings to reduce target responses, and in some circumstances delays are unavoidably imposed between the onset of a timeout and the offset of the response that produces it. The present study examined the effects of signaled and unsignaled timeouts in rats exposed to concurrent fixed-ratio 1 fixed-ratio 1 schedules of food delivery, where each response on one lever, the location of which changed across conditions, produced both food and a delayed 10-s timeout. Delays of 0 to 38 s were examined...
February 14, 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28187948/alcohol-drinking-during-adolescence-increases-consumptive-responses-to-alcohol-in-adulthood-in-wistar-rats
#2
Leslie R Amodeo, Diana Kneiber, Derek N Wills, Cindy L Ehlers
Binge drinking and the onset of alcohol-use disorders usually peak during the transition between late adolescence and early adulthood, and early adolescent onset of alcohol consumption has been demonstrated to increase the risk for alcohol dependence in adulthood. In the present study, we describe an animal model of early adolescent alcohol consumption where animals drink unsweetened and unflavored ethanol in high concentrations (20%). Using this model, we investigated the influence of drinking on alcohol-related appetitive behavior and alcohol consumption levels in early adulthood...
February 7, 2017: Alcohol
https://www.readbyqxmd.com/read/28182849/controlling-the-false-discoveries-in-lasso
#3
Hanwen Huang
The LASSO method estimates coefficients by minimizing the residual sum of squares plus a penalty term. The regularization parameter λ in LASSO controls the trade-off between data fitting and sparsity. We derive relationship between λ and the false discovery proportion (FDP) of LASSO estimator and show how to select λ so as to achieve a desired FDP. Our estimation is based on the asymptotic distribution of LASSO estimator in the limit of both sample size and dimension going to infinity with fixed ratio. We use a factor analysis model to describe the dependence structure of the design matrix...
February 9, 2017: Biometrics
https://www.readbyqxmd.com/read/28179474/individual-differences-in-the-relative-reinforcing-effects-of-3-4-methylenedioxypyrovalerone-mdpv-under-fixed-and-progressive-ratio-schedules-of-reinforcement-in-rats
#4
Brenda M Gannon, Kayla I Galindo, Kenner C Rice, Gregory T Collins
The recreational use of designer drugs, including synthetic cathinones (bath salts), is associated with high levels of abuse and toxicity, and represents a growing threat to public health. MDPV (3,4-methylenedioxypyrovalerone) is a cocaine-like monoamine uptake inhibitor, and one of the most widely available and abused synthetic cathinones. The present study used male Sprague-Dawley rats to directly compare: (1) the acquisition of responding for MDPV and cocaine under a fixed ratio (FR) 1 schedule of reinforcement; (2) full dose-response curves for MDPV and cocaine under FR5; and (3) progressive ratio (PR) schedules of reinforcement...
February 8, 2017: Journal of Pharmacology and Experimental Therapeutics
https://www.readbyqxmd.com/read/28177981/high-fat-diet-alters-weight-caloric-intake-and-haloperidol-sensitivity-in-the-context-of-effort-based-responding
#5
Stephen H Robertson, Steven R Boomhower, Erin B Rasmussen
High-fat (HF) diets result in weight gain, hyperphagia, and reduced dopamine D2 signaling; however, these findings have been obtained only under free-feeding conditions. This study tested the extent to which HF diet affects effort-dependent food procurement and the extent to which dopamine signaling is involved. Male Sprague-Dawley rats consumed either a HF (n=20) or a standard-chow (n=20) diet. We assessed the sensitivity to effort-based reinforcement in 10 rats from each group by measuring consumption across a series of fixed-ratio schedules (FR 5-FR 300) under a closed economy and quantified performance using the exponential-demand equation...
February 7, 2017: Behavioural Pharmacology
https://www.readbyqxmd.com/read/28151829/haemotherapy-algorithm-for-the-management-of-trauma-induced-coagulopathy-an-australian-perspective
#6
James Winearls, Biswadev Mitra, Michael C Reade
PURPOSE OF REVIEW: Recent advances in the understanding of the pathophysiological processes associated with traumatic haemorrhage and trauma-induced coagulopathy have resulted in improved outcomes for seriously injured trauma patients. However, a significant number of trauma patients still die from haemorrhage. This article reviews the various transfusion strategies utilized in the management of traumatic haemorrhage and describes the major haemorrhage protocol (MHP) strategy employed by an Australian trauma centre...
February 1, 2017: Current Opinion in Anaesthesiology
https://www.readbyqxmd.com/read/28150516/efficacy-and-safety-of-fixed-ratio-combination-of-insulin-degludec-and-liraglutide-ideglira-for-the-treatment-of-type-2-diabetes
#7
Louise Vedtofte, Filip K Knop, Tina Vilsbøll
Type 2 diabetes (T2D) is a progressive disease with increasing prevalence in most countries. The majority of patients with T2D have inadequate glycaemic control, which increases the risk of diabetic complications later in life. New therapies with improved safety profiles are required to tackle the progressive nature of T2D. Areas covered: The efficacy and safety profile of IDegLira - a once-daily, fixed-ratio combination of insulin degludec and liraglutide, a glucagon-like peptide-1 receptor agonist (GLP-1RA), for the treatment of T2D - has been extensively evaluated...
March 2017: Expert Opinion on Drug Safety
https://www.readbyqxmd.com/read/28137754/efficacy-and-safety-of-follitropin-alfa-lutropin-alfa-in-art-a-randomized-controlled-trial-in-poor-ovarian-responders
#8
P Humaidan, W Chin, D Rogoff, T D'Hooghe, S Longobardi, J Hubbard, J Schertz
STUDY QUESTION: How does the efficacy and safety of a fixed-ratio combination of recombinant human FSH plus recombinant human LH (follitropin alfa plus lutropin alfa; r-hFSH/r-hLH) compare with that of r-hFSH monotherapy for controlled ovarian stimulation (COS) in patients with poor ovarian response (POR)? SUMMARY ANSWER: The primary and secondary efficacy endpoints were comparable between treatment groups and the safety profile of both treatment regimens was favourable...
January 30, 2017: Human Reproduction
https://www.readbyqxmd.com/read/28127624/oxycodone-self-administration-in-male-and-female-rats
#9
Maria Mavrikaki, Marco Pravetoni, Sarah Page, David Potter, Elena Chartoff
RATIONALE: Oxycodone is one of the most widely prescribed painkillers in the USA. However, its use is complicated by high abuse potential. As sex differences have been described in drug addiction, the present study tested for sex differences in intravenous oxycodone self-administration in rats. METHODS: Male and female Sprague-Dawley rats were implanted with jugular vein catheters and trained to self-administer oxycodone (0.03 mg/kg/infusion) under fixed ratio 1 (FR1), FR2, and FR5 schedules of reinforcement followed by a dose-response study to assess sensitivity to the reinforcing effects of oxycodone...
January 27, 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28126283/fenton-process-on-single-and-mixture-components-of-phenothiazine-pharmaceuticals-assessment-of-intermediaries-fate-and-preliminary-ecotoxicity
#10
Marcelo L Wilde, Mandy Schneider, Klaus Kümmerer
Pharmaceuticals do not occur isolated in the environment but in multi-component mixtures and may exhibit antagonist, synergistic or additive behavior. Knowledge on this is still scarce. The situation is even more complicated if effluents or potable water is treated by oxidative processes or such transformations occur in the environment. Thus, determining the fate and effects of parent compounds, metabolites and transformation products (TPs) formed by transformation and degradation processes in the environment is needed...
January 23, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28101925/-watch-out-effects-of-instructed-threat-and-avoidance-on-human-free-operant-approach-avoidance-behavior
#11
Michael W Schlund, Kay Treacher, Oli Preston, Sandy K Magee, David M Richman, Adam T Brewer, Gemma Cameron, Simon Dymond
Approach-avoidance paradigms create a competition between appetitive and aversive contingencies and are widely used in nonhuman research on anxiety. Here, we examined how instructions about threat and avoidance impact control by competing contingencies over human approach-avoidance behavior. Additionally, Experiment 1 examined the effects of threat magnitude (money loss amount) and avoidance cost (fixed ratio requirements), whereas Experiment 2 examined the effects of threat information (available, unavailable and inaccurate) on approach-avoidance...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28101921/effects-of-shifts-in-food-reinforcement-context-on-rats-consumption-of-concurrently-available-water-or-sucrose-solution
#12
Chad M Galuska, Leslie E Sawyer
The purpose of this study was to investigate the effects of signaled transitions from relatively rich to lean conditions of food reinforcement on drinking concurrently available water or sucrose-sweetened water in rats. Past research demonstrated that these negative incentive shifts produce behavioral disruption in the form of extended pausing on fixed-ratio schedules. Four male Long-Evans rats operated on a two-component multiple fixed-ratio fixed-ratio schedule. In one manipulation, the ratio was held constant and the components arranged either a large six-pellet reinforcer (rich) or small one-pellet reinforcer (lean)...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28078744/escape-from-rich-to-lean-transitions-stimulus-change-and-timeout
#13
Billie J Retzlaff, Elizabeth T P Parthum, Raymond C Pitts, Christine E Hughes
Extended pausing during discriminable transitions from rich-to-lean conditions can be viewed as escape (i.e., rich-to-lean transitions function aversively). In the current experiments, pigeons' key pecking was maintained by a multiple fixed-ratio fixed-ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition-specific stimulus used in the multiple schedule to a mixed-schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2)...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28078680/children-s-preference-for-mixed-versus-fixed-ratio-schedules-of-reinforcement-a-translational-study-of-risky-choice
#14
Michael P Mullane, Brian K Martens, Emily L Baxter, Danica Ver Steeg
Laboratory research has shown that when subjects are given a choice between fixed-ratio and bi-valued mixed-ratio schedules of reinforcement, preference typically emerges for the mixed-ratio schedule even with a larger ratio requirement. The current study sought to replicate and extend these findings to children's math problem completion. Using an ABCBC reversal design, four fourth-grade students were given the choice of completing addition problems reinforced on either a fixed-ratio 5 schedule or one of three mixed-ratio schedules; an equivalent mixed-ratio (1, 9) schedule, a mixed-ratio (1, 11) schedule with a 20% larger ratio requirement, and an equally lean mixed-ratio (5, 7) schedule without the small fixed-ratio 1 component...
January 2017: Journal of the Experimental Analysis of Behavior
https://www.readbyqxmd.com/read/28077308/cookie-or-fruit-relative-reinforcing-value-of-snack-foods-among-preschoolers-with-overweight-obesity-compared-to-healthy-weight
#15
Mary Beth McCullough, Hayley Guilkey, Lori Stark
The reinforcing value of food is an important determinant of food intake. Research has yet to examine the relative reinforcing value (RRV) of snack foods in young children with overweight and obesity (OW/OB). The current study compared the RRV of high-energy dense foods (cookies) to low-energy dense foods (fruits) between preschoolers with OW/OB and healthy weight (HW). RRV of cookies and fruits in preschoolers with OW/OB (n = 30; Mage = 4.4 ± 0.84; 60% male) and HW (n = 30; Mage = 4.5 ± 0.85; 70% male) was assessed with a developmentally-tailored computer program which used a progressive fixed ratio reward schedule...
January 8, 2017: Appetite
https://www.readbyqxmd.com/read/28065844/effects-of-the-chronic-restraint-stress-induced-depression-on-reward-related-learning-in-rats
#16
Pan Xu, Kezhu Wang, Cong Lu, Liming Dong, Yixi Chen, Qiong Wang, Zhe Shi, Yanyan Yang, Shanguang Chen, Xinmin Liu
Chronic mild or unpredictability stress produces a persistent depressive-like state. The main symptoms of depression include weight loss, despair, anhedonia, diminished motivation and mild cognition impairment, which could influence the ability of reward-related learning. In the present study, we aimed to evaluate the effects of chronic restraint stress on the performance of reward-related learning of rats. We used the exposure of repeated restraint stress (6h/day, for 28days) to induce depression-like behavior in rats...
March 15, 2017: Behavioural Brain Research
https://www.readbyqxmd.com/read/28059083/behavioral-determinants-of-cannabinoid-self-administration-in-old-world-monkeys
#17
William S John, Thomas J Martin, Michael A Nader
Reinforcing effects of Δ(9)-tetrahydrocannabinol (THC), the primary active ingredient in marijuana, as assessed with self-administration (SA), has only been established in New World primates (squirrel monkeys). The objective of this study was to investigate some experimental factors that may enhance intravenous SA of THC and the cannabinoid receptor (CBR) agonist CP 55 940 in Old World monkeys (rhesus and cynomolgus), a species that has been used extensively in biomedical research. In one experiment, male rhesus monkeys (N=9) were trained to respond under a fixed-ratio 10 schedule of food presentation...
February 1, 2017: Neuropsychopharmacology: Official Publication of the American College of Neuropsychopharmacology
https://www.readbyqxmd.com/read/28033493/the-time-dependent-synergism-of-the-six-component-mixtures-of-substituted-phenols-pesticides-and-ionic-liquids-to-caenorhabditis-elegans
#18
Li Feng, Shu-Shen Liu, Kai Li, Han-Xiao Tang, Hai-Ling Liu
Traditional environmental risk assessment rarely focused on exposures to multi-component mixtures which may cause toxicological interactions and usually ignored that toxicity is a process in time, which may underestimate the environment risk of mixtures. In this paper, six chemicals belonging to three categories, two substituted phenols, two pesticides and two Ionic liquids, were picked to construct a six-component mixture system. To systematically examine the effects of various concentration compositions, the uniform design ray method was employed to design nine mixture rays with nine mixture ratios and for every mixture ray 12 concentration levels were specified by the fixed ratio ray design...
December 19, 2016: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28007642/suppressing-effect-of-saikosaponin-a-an-active-ingredient-of-bupleurum-falcatum-on-chocolate-self-administration-and-reinstatement-of-chocolate-seeking-in-rats
#19
Irene Lorrai, Paola Maccioni, Mauro A M Carai, Alessandro Capra, M Paola Castelli, Antonella Riva, Paolo Morazzoni, Gian Luigi Gessa, Giancarlo Colombo
Recent lines of experimental evidence have indicated that saikosaponin A (SSA) - a bioactive ingredient of the medicinal plant, Bupleurum falcatum L. - suppressed alcohol, morphine, and cocaine self-administration in rats. The present paper was designed to assess whether the protective properties of SSA on addiction-related behaviors generalize to a hyperpalatable food such as a chocolate-flavored beverage (CFB). To this end, rats were initially trained to lever-respond for CFB [5% (w/v) Nesquik(®) powder in water] under fixed ratio (FR) 10 (FR10) schedule of reinforcement...
December 19, 2016: Neuroscience Letters
https://www.readbyqxmd.com/read/28000221/substitution-effects-in-a-generalized-token-economy-with-pigeons
#20
Leonardo F Andrade, Timothy D Hackenberg
Pigeons made repeated choices between earning and exchanging reinforcer-specific tokens (green tokens exchangeable for food, red tokens exchangeable for water) and reinforcer-general tokens (white tokens exchangeable for food or water) in a closed token economy. Food and green food tokens could be earned on one panel; water and red water tokens could be earned on a second panel; white generalized tokens could be earned on either panel. Responses on one key produced tokens according to a fixed-ratio schedule, whereas responses on a second key produced exchange periods, during which all previously earned tokens could be exchanged for the appropriate commodity...
January 2017: Journal of the Experimental Analysis of Behavior
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