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1.
Neven Sesardić 《Journal for General Philosophy of Science》1992,23(1):129-151
In contrast to the opinion of numerous authors (e.g. R. Rudner, P. Kitcher, L. R. Graham, M. Dummett, N. Chomsky, R. Lewontin, etc.) it is argued here that the formation of opinion in science should be greatly insulated from political considerations. Special attention is devoted to the view that methodological standards for evaluation of scientific theories ought to vary according to the envisaged political uses of these theories.I wish to thank the Alexander von Humboldt Foundation for having supported the work on this paper. 相似文献
2.
Nicholas Rescher 《Argumentation》1987,1(3):303-316
Consistency is often pictured as an indispensable requisite for rationality. The paper argues that this is overly rigoristic. Inconsistency can be treated as a matter of isolable singularities rather than an all-destructive disaster. The paper, supports and illustrates a perspective on which consistency can be seen as a desideratum rather than a totaly non-negotiable demand. The argumentation of the paper casts consistency in the role of a cognitive ideal rather than a sine qua non condition of rational process. 相似文献
3.
Concurrent access to two concentrations of orally delivered phencyclidine: effects of feeding conditions. 总被引:1,自引:1,他引:0
M E Carroll 《Journal of the experimental analysis of behavior》1987,47(3):347-362
Two experiments addressed the effects of food satiation and deprivation on oral self-administration of two concurrently available phencyclidine concentrations. In the first experiment, 8 rhesus monkeys self-administered either of two concentrations of phencyclidine ("PCP, angel dust") and water under concurrent fixed-ratio 16 schedules. One concentration was always held constant (0.25 mg/mL) while a series of other phencyclidine concentrations, ranging from 0 (water) to 1.0 mg/mL, was presented in a nonsystematic order. Initially the monkeys were tested while food satiated, and the procedure was then repeated during food deprivation. The monkeys usually selected the higher concentration within the first few minutes of the session, indicating that taste and/or other immediate postingestional effects were important factors. Contrary to a number of previous reports, there were no consistent differences across subjects in the mean number of liquid deliveries or mean drug intake (mg/kg) during food satiation and deprivation. However, for all monkeys the within-session time course of responding during food satiation consistently differed from that during deprivation. A second experiment assessed whether the failure to find consistent differences in drug intake during food satiation and deprivation had been due to the history of concurrent access to different phencyclidine concentrations or to the extended experience with phencyclidine under food-satiation conditions. Six additional monkeys (Group 2) were exposed to the phencyclidine self-administration procedure (during food satiation and deprivation) for the same length of time as the monkeys in Experiment 1 (Group 1), except they received only concurrent access to phencyclidine (0.25 mg/mL) and water. Both groups then received concurrent access to phencyclidine and water during five repeated cycles of food deprivation and satiation. There were also marked individual differences in Group 2: During food satiation, 2 of the monkeys' responding increased, 1 showed no change, and 3 decreased. Examination of a number of historical variables indicated that the greater the percentage of total sessions spent during food satiation with phencyclidine available (before these experiments began), the greater the amounts of phencyclidine consumed during food satiation and the smaller the differences in phencyclidine intake when the two feeding conditions were compared. 相似文献
4.
Lana M. Mahon Norma Neufeld Mani M. Mani Edward R. Christophersen 《Journal of applied behavior analysis》1984,17(3):391-396
The effect of informational feedback on the protein and caloric consumption of burn patients was investigated using a multiple-baseline across subjects. The patients were four severely burned adult males who failed to consume sufficient foods to achieve prescribed levels of protein or kilocalories via standard burn unit procedures during recovery. Feedback consisted of informing patients of (a) their prescribed levels of protein and kilocalories, (b) the protein and kilocalorie content of hospital foods and beverages, and (c) their actual intake of protein and kilocalories. Following the provision of feedback, there was an increase in protein and kilocalorie intakes and in the number of days during which prescribed levels for protein and kilocalories were achieved. These results suggest that the informational feedback was effective for improving the oral caloric intake of burn patients. 相似文献
5.
Food stealing is often a serious behavioral problem among children with diagnoses of autism and other developmental disorders. Very few empirical studies concerning this behavioral challenge have been reported. We applied a correspondence training procedure to teach self-control as replacement behavior to four children with autism and developmental disorders who displayed food stealing in the community. A changing criterion design embedded within a nonconcurrent multiple-probe across participants design was used. The treatment succeeded for all four participants by increasing latency to eating highly preferred food to a predetermined criterion and reducing occurrences of food stealing to zero. Three participants generalized the replacement behavior to natural settings and maintained the behavior for 2 weeks, 1 month, 2 months, 3 months, and 4 months. One participant without expressive language was taught successfully during treatment trials but failed to maintain and generalize the behavior. A functional relation between delaying food eating and Say-Do correspondence training was demonstrated. 相似文献
6.
Patrick L. Hill Caryn E. Oshiro Teresa A. Hillier Victor J. Strecher 《Social and Personality Psychology Compass》2023,17(11):e12869
The COVID-19 pandemic brought new attention to the issues of food insecurity faced by individuals throughout the United States, a stressor exacerbated by disruptions to work status and supply chains. The burden of food insecurity likely carries consequences for whether individuals feel capable of pursuing their broad goals and life engagements; put differently, food insecurity may pose a threat to people perceiving a sense of purpose in life. The current study tested this claim across three samples taken during 2020 (n = 2009), 2021 (n = 1666), and 2022 (n = 1975). Participants completed inventories for perceived food insecurity, sense of purpose, depressive symptoms, and anxiety, among other measures. Results found consistent negative associations between food insecurity and sense of purpose across all three samples. In addition, food insecurity moderated associations between sense of purpose and depressive or anxiety symptoms. Sense of purpose was more strongly negatively associated with depressive and anxiety symptoms for those participants who reported no food insecurity. That said, sense of purpose remained negatively associated with psychological distress even among those reporting food insecurity. 相似文献
7.
Food and amphetamine self-administration by baboons: effects of alternatives. 总被引:2,自引:2,他引:0 下载免费PDF全文
R W Foltin 《Journal of the experimental analysis of behavior》1997,68(1):47-66
The effects of the availability of an alternative reinforcer on responding maintained by food pellets or fluid solutions were examined in 6 adult male baboons (Papio cynocephalus anubis). During daily 23-hr experimental sessions, baboons had concurrent access to both food pellets and fluid, with responding maintained under fixed-ratio schedules of reinforcement that varied between the two commodities. The fixed-ratio requirement, or cost, for pellets was increased when (a) no fluid, (b) a dilute dextrose vehicle, (c) 0.002 mg/kg d-amphetamine, or (d) 0.004 mg/kg d-amphetamine was available. When given nonrestricted concurrent access to food pellets and amphetamine at minimal cost (FR 2), baboons self-administered sufficient amphetamine to decrease pellet intake. Increasing the response requirement for pellets decreased pellet intake at a similar rate regardless of the available fluid and increased fluid intake in a variable manner among baboons such that there were no statistically significant increases in fluid intake. In contrast, when access to pellets was restricted to 70% of maximal intake under nonrestricted conditions, increasing pellet cost decreased pellet intake and increased fluid intake more rapidly when the high amphetamine dose was available. Thus, amphetamine was more effective as an economic substitute for pellets when access to pellets was restricted. The response cost for vehicle and both amphetamine concentrations was increased when baboons had nonrestricted and restricted access to pellets. Increasing the response requirement for fluid delivery decreased intake of all three fluids similarly under both pellet-access conditions. The results indicate that substitution between commodities with minimal commonalities can be studied under controlled laboratory conditions and is dependent upon reinforcement schedule and commodity restrictions. 相似文献
8.
Self-control and impulsiveness in children and adults: Effects of food preferences 总被引:1,自引:0,他引:1 下载免费PDF全文
Experiment 1 used 6 preschool boys and Experiment 2 used 6 adult women to explore the effects of food preference on humans' choice in self-control paradigms. The boys showed a higher proportion of responses for more delayed, larger reinforcers (a measure of self-control) when those choices resulted in receipt of the most preferred food compared to when those choices resulted in the least preferred food. Further, the boys chose the less delayed, smaller reinforcers significantly more often when only those choices, as opposed to both choices, resulted in the most preferred food. Conversely, they chose the more delayed, larger reinforcers significantly more often when only those choices, as opposed to both choices, resulted in the most preferred food. Finally, the women demonstrated significantly less sensitivity to reinforcer amount relative to sensitivity to reinforcer delay (another measure of self-control) when they had a higher preference for the juice received as the less delayed, smaller reinforcer than for the juice received as the more delayed, larger reinforcer. Together, the results show that subjects' food preferences can influence self-control for food reinforcers. 相似文献
9.
Food-deprived rats (at 80% of their free-feeding weights) were exposed to a fixed-time 60-s schedule of food-pellet presentation and developed schedule-induced drinking. Lick-dependent signaled delays (10 s) to food presentation led to decreased drinking, which recovered when the signaled delays were discontinued. A major effect of this punishment contingency was to increase the proportion of interpellet intervals without any licks. The drinking of yoked control rats, which received food at the same times as those exposed to the signaled delay contingency (masters), was not consistently reduced. When food-deprivation level was changed to 90%, all master and yoked control rats showed decreases in punished or unpunished schedule-induced drinking. When the body weights were reduced to 70%, most master rats increased punished behavior to levels similar to those of unpunished drinking. This effect was not observed for yoked controls. Therefore, body-weight loss increased the resistance of schedule-induced drinking to reductions by punishment. Food-deprivation effects on punished schedule-induced drinking are similar to their effects on food-maintained lever pressing. This dependency of punishment on food-deprivation level supports the view that schedule-induced drinking can be modified by the same variables that affect operant behavior in general. 相似文献
10.
Terry L. Rose 《Journal of applied behavior analysis》1978,11(4):439-446
The presence of a functional relationship between the ingestion of artificial food colors and an increase in the frequency and/or duration of selected behaviors that are representative of the hyperactive behavior syndrome was experimentally investigated. Two eight-year-old females, who had been on the Feingold K-P diet for a minimum of 11 months, were the subjects studied. The experimental design was a variation of the BAB design, with double-blind conditions. This design allowed an experimental analysis of the placebo phases as well as challenge phases. Data were obtained by trained observers on Out of Seat, On Task, and Physically Aggressive behaviors, as they occurred in the subjects' regular class setting. Results indicated (a) the existence of a functional relationship between the ingestion of artificial food colors and an increase in both the duration and frequency of hyperactive children. 相似文献