Effect of Reinforcement of the Negative Discriminandum in Differential Conditioning

1964 ◽  
Vol 14 (1) ◽  
pp. 107-110 ◽  
Author(s):  
Peter J. Donovick ◽  
Leonard E. Ross

The present investigation was concerned with the reduction of inhibition associated with the negative discriminandum in a single stimulus discrimination learning situation. In Phase I 33 female rats were trained on a black-white discrimination problem. In the second phase Ss were divided into three groups which received: (a) 100% reinforcement to both the old positive and negative discriminanda; (b) four trials per day to the old negative, 100% reward; (c) eight trials per day to the old negative, 100% reward. As in previous studies, which employed simultaneous discrimination learning conditions, speed to the old negative remained significantly below speed to the old positive in the second phase. However, unlike the previous results, the difference decreased over trials. No differences were found between the groups that had trials to the old negative cue only, or between these groups and either speed to the old positive or the old negative in the case of the group receiving reward on both cues.

1904 ◽  
Vol 73 (488-496) ◽  
pp. 92-98 ◽  
Author(s):  
Augustus Desire Waller

In a previous communication it was stated that the electrical signs a of secreto-motor action by tetanisation of the sciatic nerve are a demonstrable in the pads of a cat’s foot after death, best so during; the second half-hour after death, when the action of the nerve upon muscles of the limb has ceased. The subsequent study of these effects, by means of electrometer records, has brought out with great distinctness the chief classical events with which we are familiar in the case of the contraction of voluntary muscle, viz., the latency and course of a single response to a single stimulus, the super-position of two or more responses and the composition of tetanus, summation of stimuli, fatigue and recovery, and the staircase phenomenon. The difference between the muscular and the secreto-motor series of phenomena is principally a difference of time, the former being about 100 times more rapid than the latter.


2016 ◽  
Vol 45 (6) ◽  
pp. 256
Author(s):  
M Mexitalia ◽  
Yohanes Tri Nugroho ◽  
J C Susanto

Background Preschool children are vulnerable in growth. Soy-bean formula (SF) and formula-100 (F100) are supplementary foodswhich contain of high energy and are available at low price; how-ever, they are not widely used for preschool children.Objectives To investigate the effect of SF compared to F100 onthe growth of preschool children.Methods A cross-over trial was conducted on 96 preschool chil-dren aged 4-7 years. Subjects were randomly divided into 2 groupswhich received 200 ml soybean formula (n=49) or F100 (n=47) for1 month and crossed-over after a six-week wash-out period. Bodyweight was measured weekly. Body height and food analysis by 3-day food recall were measured at the beginning and the end of thestudy. The criteria of the acceptability of the formula was eithergood or poor.Results Supplementation with SF as well as F100 induced catchup growth as shown by the increase of Δz-score. There were nosignificant difference of Δ weight for age z-score, Δ height for agez-score, and Δ weight for height z score between groups duringthe first and second phases of the trial. The acceptability of F100was significantly better than that of SF at the beginning; neverthe-less, the difference was not significant at the second phase trial.Conclusions Soybean formula and F100 given for a one monthperiod can induce catch-up growth in preschool children. Soybeanformula as an alternative health food can be accepted by preschoolchildren


Author(s):  
Oussama Choura ◽  
Caterina Capponi ◽  
Silvia Meniconi ◽  
Sami Elaoud ◽  
Bruno Brunone

Abstract In this paper the results of an experimental validation of a technique for leak detection in polymeric pipes based on the inverse transient analysis (ITA) are presented. In the proposed ITA the Nelder–Mead algorithm is used as a calibration tool. Experimental tests have been carried out in an intact and leaky high-density polyethylene (HDPE) single pipe installed at the Water Engineering Laboratory (WEL) of the University of Perugia, Italy. Transients have been generated by the fast and complete closure of a valve placed at the downstream end section of the pipe. In the first phase of the calibration procedure, the proposed algorithm has been used to estimate both the viscoelastic parameters of a generalized Kelvin–Voigt model and the unsteady-state friction coefficient, by minimizing the difference between the numerical and experimental results. In the second phase of the procedure, the calibrated model allowed the evaluation of leak size and location with an acceptable accuracy. Precisely, in terms of leak location the relative error was smaller than 5%.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nhat Thanh Hoang Le ◽  
Nhan Thi Ho ◽  
Bryan Grenfell ◽  
Stephen Baker ◽  
Ronald B. Geskus

Abstract Background Infection with measles virus (MeV) causes immunosuppression and increased susceptibility to other infectious diseases. Only few studies reported a duration of immunosuppression, with varying results. We investigated the effect of immunosuppression on the incidence of hospital admissions for infectious diseases in Vietnamese children. Methods We used retrospective data (2005 to 2015; N = 4419) from the two pediatric hospitals in Ho Chi Minh City, Vietnam. We compared the age-specific incidence of hospital admission for infectious diseases before and after hospitalization for measles. We fitted a Poisson regression model that included gender, current age, and time since measles to obtain a multiplicative effect measure. Estimates were transformed to the additive scale. Results We observed two phases in the incidence of hospital admission after measles. The first phase started with a fourfold increased rate of admissions during the first month after measles, dropping to a level quite comparable to children of the same age before measles. In the second phase, lasting until at least 6 years after measles, the admission rate decreased further, with values up to 20 times lower than in children of the same age before measles. However, on the additive scale the effect size in the second phase was much smaller than in the first phase. Conclusion The first phase highlights the public health benefits of measles vaccination by preventing measles and immune amnesia. The beneficial second phase is interesting, but its strength strongly depends on the scale. It suggests a complicated interaction between MeV infection and the host immunity.


Art Scents ◽  
2020 ◽  
pp. 37-50
Author(s):  
Larry Shiner

Chapter 2 begins by exploring the biology of the human olfactory system, including the difference between orthonasal and retronasal smell, then surveys contemporary research on the characteristics of smell, as revealed by neuroimaging, that indicates its cognitive capacity for detection, discrimination, learning, and social communication. A special section on the “odor object” discusses debates within the current philosophy of perception on whether it is appropriate to speak of odors as “objects.” The sections on detection, discrimination, and learning show that current science indicates that humans have much sharper abilities in all these areas than is popularly believed. The topic of communication leads naturally to another brief interlude, “The Pheromone Myth.”


2018 ◽  
Vol 192 ◽  
pp. 01022
Author(s):  
Ekkaphon Jaiyen ◽  
Komgrit Leksakul

This research objective is to solve the integer problems by using an algorithm that applied to the element decomposing method (EDCM). Integer problem is a NP-hard when the problem is large-size, more time needed to solve the problem. The EDCM cuts a structure into several elements and reconnects elements at “nodes”. This process can disconnect other nodes that not connected with the element. Moreover, it appropriately need in optimization solutions for applications, in which can give answers faster by cutting the nodes in finding the answers. There’s 2 phases of step on this research. The first phase is input data and simplex method, while the second phase is creating and developing the algorithm from EDCM application. The comparison results show how two methods are carried out between EDCM and B&B Method. The results from two methods are focused on the value and solution step by step. According to the problem, it can be solved within the number of variables 2-15. The value of the difference in the answer is on average at 0.00% and solution step used for solving problem is less on average at 40.89 %.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Mohammad Javad Fatemi ◽  
Mostafa Dianatinasab ◽  
Golnaz Sharifnia ◽  
Hossein Moravej ◽  
Mohammad Fararouei

Abstract Background Growth retardation is a common health problem, which requires early prevention and detection. This study was conducted to define the approximate age at which stunting starts among the Iranian boys and girls. Method The second phase of a population-based retrospective cohort nested case-control study on 400 children who were followed from birth to 7 years of age. This study was performed to define the pattern of growth among stunted and normal children and to reveal the age at which stunting starts in each gender. Results Of the selected participants, 53% were girls. Also, about 18% of the children registered by the selected health centers were defined as stunted (under the 3rd percentile of the corresponding sex-age NCHS/WHO growth reference). For boys, the height was relatively similar between the two groups until the age of 6 months at which the difference in height between normal and stunted children starts to become significantly large (difference = 0.70 cm, P = 0.04). For girls, height in the two groups is relatively similar until the age of 9 months at which the difference starts to become significantly large (difference = 0.97 cm, P = 0.01). No significant difference in the weight of the girls was observed between the normal and stunted groups during the study period (difference = 283.21 g, P > 0.05). However, boys from the stunted group were lighter since almost the same time that they started to become significantly shorter (difference = 1265.19 g, P = 0.001). Conclusions Soon after birth (at about the 6 months of age), the growth pattern of some (stunted) children starts to stumble and divert from normal. The sixth month of age is the age at which mothers start weaning with withdrawing breast milk and start supplementary foods and adult diet. A specially designed study is needed to understand the actual reason for observing such a phenomenon among Iranian children.


Drug Research ◽  
2020 ◽  
Vol 70 (04) ◽  
pp. 145-150 ◽  
Author(s):  
Viviana Noriega ◽  
Hugo F. Miranda ◽  
Juan Carlos Prieto ◽  
Ramón Sotomayor-Zárate ◽  
Fernando Sierralta

AbstractThere are different animal models to evaluate pain among them the formalin hind paw assay which is widely used since some of its events appear to be similar to the clinical pain of humans. The assay in which a dilute solution of formalin is injected into the dorsal hindpaw of a murine produces two ‘phases’ of pain behavior separated by a inactive period. The early phase (Phase I) is probably due to direct activation of nociceptors and the second phase (Phase II) is due to ongoing inflammatory input and central sensitization. Mice were used to determine the potency antinociceptive of piroxicam (1,3,10,and 30 mg/kg), parecoxib (0.3, 1,3,10 and 30 mg/kg), dexketoprofen (3,10,30 and 100 mg/kg) and ketoprofen (3,10,30 and 100 mg/kg). Dose-response for each NSAIDs were created before and after 5 mg/kg of L-NAME i.p. or 5 mg/kg i.p. of 7-nitroindazole. A least-squares linear regression analysis of the log dose–response curves allowed the calculation of the dose that produced 50% of antinociception (ED50) for each drug. The ED50 demonstrated the following rank order of potency, in the phase I: piroxicam > dexketoprofen > ketoprofen > parecoxib and in the phase II: piroxicam > ketoprofen > parecoxib > dexketoprofen. Pretreatment of the mice with L-NAME or 7-nitroindazol induced a significant increase of the analgesic power of the NSAIDs, with a significant reduction of the ED50. It is suggested that NO may be involved in both phases of the trial, which means that nitric oxide regulates the bioactivity of NSAIDs.


2018 ◽  
Vol 33 (09) ◽  
pp. 1843004 ◽  
Author(s):  
◽  
M. Agostini ◽  
A. M. Bakalyarov ◽  
M. Balata ◽  
I. Barabanov ◽  
...  

The GERmanium Detector Array (GERDA) is a low background experiment at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN designed to search for the rare neutrinoless double beta decay ([Formula: see text]) of [Formula: see text]Ge. In the first phase (Phase I) of the experiment, high purity germanium diodes were operated in a “bare” mode and immersed in liquid argon. The overall background level of [Formula: see text] was a factor of ten better than those of its predecessors. No signal was found and a lower limit was set on the half-life for the [Formula: see text] decay of [Formula: see text]Ge [Formula: see text] yr (90% CL), while the corresponding median sensitivity was [Formula: see text] yr (90% CL). A second phase (Phase II) started at the end of 2015 after a major upgrade. Thanks to the increased detector mass and performance of the enriched germanium diodes and due to the introduction of liquid argon instrumentation techniques, it was possible to reduce the background down to [Formula: see text]. After analyzing 23.2 kg[Formula: see text]⋅[Formula: see text]yr of these new data no signal was seen. Combining these with the data from Phase I a stronger half-life limit of the [Formula: see text]Ge [Formula: see text] decay was obtained: [Formula: see text] yr (90% CL), reaching a sensitivity of [Formula: see text] yr (90% CL). Phase II will continue for the collection of an exposure of 100 kg[Formula: see text]yr. If no signal is found by then the GERDA sensitivity will have reached [Formula: see text] yr for setting a 90% CL. limit. After the end of GERDA Phase II, the flagship experiment for the search of [Formula: see text] decay of [Formula: see text]Ge will be LEGEND. LEGEND experiment is foreseen to deploy up to 1-ton of [Formula: see text]Ge. After ten years of data taking, it will reach a sensitivity beyond 10[Formula: see text] yr, and hence fully cover the inverted hierarchy region.


2018 ◽  
Vol 48 (2) ◽  
pp. 76-84 ◽  
Author(s):  
Halvor Moxnes

This homage to Bruce Malina describes his visit to Norway in 1986, and reviews Nordic scholarship using social science criticism in New Testament and Early Christian studies in the last 40 years. Based on a common history and collaboration in academic politics, the Nordic countries make up a unity that has made it possible to establish Nordic studies in Early Christianity as a central player in international scholarship. Nordic scholars have especially been active in the second phase of social science criticism with its focus on social identities and ritual. Their most significant contribution has been in the exploration of socio-cognitive perspectives, where Helsinki University has had a leading role. A major discussion has been the relation between social-science criticism emphasizing the difference between antiquity and the modern world, and cognitive studies that focus on similarity. However, instead of absolute contrasts they may be regarded as supplementary approaches in historical studies of Early Christianity.


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