Indirect reciprocity with trinary reputations.

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Tanabe, Shoma; Suzuki, Hideyuki; Masuda, Naoki

2013-01-21

Indirect reciprocity is a reputation-based mechanism for cooperation in social dilemma situations when individuals do not repeatedly meet. The conditions under which cooperation based on indirect reciprocity occurs have been examined in great details. Most previous theoretical analysis assumed for mathematical tractability that an individual possesses a binary reputation value, i.e., good or bad, which depends on their past actions and other factors. However, in real situations, reputations of individuals may be multiple valued. Another puzzling discrepancy between the theory and experiments is the status of the so-called image scoring, in which cooperation and defection are judged to be good and bad, respectively, independent of other factors. Such an assessment rule is found in behavioral experiments, whereas it is known to be unstable in theory. In the present study, we fill both gaps by analyzing a trinary reputation model. By an exhaustive search, we identify all the cooperative and stable equilibria composed of a homogeneous population or a heterogeneous population containing two types of players. Some results derived for the trinary reputation model are direct extensions of those for the binary model. However, we find that the trinary model allows cooperation under image scoring under some mild conditions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evidence of direct reciprocity, but not of indirect and generalized reciprocity, in the grooming exchanges of wild Barbary macaques (Macaca sylvanus).

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Molesti, Sandra; Majolo, Bonaventura

2017-09-01

Reciprocity is one of the mechanisms that have been proposed to explain the exchange of social behaviors, such as grooming, in animals. Reciprocity assumes that individuals act as the donor and recipient of grooming and switch roles over time to balance the benefits and costs of this behavior. Three main patterns of reciprocity may follow a grooming given: (i) direct reciprocity, where the former recipient returns the grooming to the former donor; (ii) indirect reciprocity, where another individual returns the grooming to the former donor; and (iii) generalized reciprocity, where the former recipient returns the grooming to another individual. While there is evidence that direct reciprocity plays an important role in various species of animals, the role of indirect and generalized reciprocity is less clear and has been rarely analyzed. We tested the role of direct, indirect, and generalized reciprocity in explaining grooming exchanges of wild Barbary macaques, by analyzing the temporal contingency between giving and receiving grooming. We collected the occurrence and latency of the three types of grooming reciprocation during 1 hr long focal sessions run simultaneously on two partners who just stopped grooming (post-grooming session) or who were in proximity (i.e., within 1.5 m) without grooming each other (control session). We ran the analyses on 284 post-grooming and 63 control sessions. The results revealed a temporal contingency of grooming interactions exchanged according to direct reciprocity but not according to indirect or generalized reciprocity. Our results indicate that grooming distribution in Barbary macaques is partner-specific. We discuss the possible role of cognition and emotions in explaining direct reciprocity in animals. © 2017 Wiley Periodicals, Inc.

Indirect reciprocity provides a narrow margin of efficiency for costly punishment

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Iwasa, Yoh; Nowak, Martin A.

2008-01-01

Indirect reciprocity1-5 is a key mechanism for the evolution of human cooperation. Our behavior toward other people depends not only on what they have done to us, but also on what they have done to others. Indirect reciprocity works via reputation5-17. The standard model of indirect reciprocity offers a binary choice: people can either cooperate or defect. Cooperation implies a cost for the donor and a benefit for the recipient. Defection has no cost and yields no benefit. Currently there is considerable interest in studying the effect of costly (or altruistic) punishment on human behavior18-25. Punishment implies a cost for the punished person. Costly punishment means that the punisher also pays a cost. It has been suggested that costly punishment between individuals can promote cooperation. Here we study the role of costly punishment in an explicit model of indirect reciprocity. We analyze all social norms, which depend on the action of the donor and the reputation of the recipient. We allow errors in assigning reputation and study gossip as a mechanism for establishing coherence. We characterize all strategies that allow the evolutionary stability of cooperation. Some of those strategies use costly punishment, while others do not. We find that punishment strategies typically reduce the average payoff of the population. Consequently, there is only a small parameter region where costly punishment leads to an efficient equilibrium. In most cases, the population does better by not using costly punishment. The efficient strategy for indirect reciprocity is to withhold help for defectors rather than punish them. PMID:19122640

Deception Undermines the Stability of Cooperation in Games of Indirect Reciprocity.

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Számadó, Szabolcs; Szalai, Ferenc; Scheuring, István

2016-01-01

Indirect reciprocity is often claimed as one of the key mechanisms of human cooperation. It works only if there is a reputational score keeping and each individual can inform with high probability which other individuals were good or bad in the previous round. Gossip is often proposed as a mechanism that can maintain such coherence of reputations in the face of errors of transmission. Random errors, however, are not the only source of uncertainty in such situations. The possibility of deceptive communication, where the signallers aim to misinform the receiver cannot be excluded. While there is plenty of evidence for deceptive communication in humans the possibility of deception is not yet incorporated into models of indirect reciprocity. Here we show that when deceptive strategies are allowed in the population it will cause the collapse of the coherence of reputations and thus in turn it results the collapse of cooperation. This collapse is independent of the norms and the cost and benefit values. It is due to the fact that there is no selection for honest communication in the framework of indirect reciprocity. It follows that indirect reciprocity can be only proposed plausibly as a mechanism of human cooperation if additional mechanisms are specified in the model that maintains honesty.

Deception Undermines the Stability of Cooperation in Games of Indirect Reciprocity.

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Szabolcs Számadó

Full Text Available Indirect reciprocity is often claimed as one of the key mechanisms of human cooperation. It works only if there is a reputational score keeping and each individual can inform with high probability which other individuals were good or bad in the previous round. Gossip is often proposed as a mechanism that can maintain such coherence of reputations in the face of errors of transmission. Random errors, however, are not the only source of uncertainty in such situations. The possibility of deceptive communication, where the signallers aim to misinform the receiver cannot be excluded. While there is plenty of evidence for deceptive communication in humans the possibility of deception is not yet incorporated into models of indirect reciprocity. Here we show that when deceptive strategies are allowed in the population it will cause the collapse of the coherence of reputations and thus in turn it results the collapse of cooperation. This collapse is independent of the norms and the cost and benefit values. It is due to the fact that there is no selection for honest communication in the framework of indirect reciprocity. It follows that indirect reciprocity can be only proposed plausibly as a mechanism of human cooperation if additional mechanisms are specified in the model that maintains honesty.

The evolution of conditional moral assessment in indirect reciprocity

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Sasaki, Tatsuya; Okada, Isamu; Nakai, Yutaka

2017-01-01

Indirect reciprocity is a major mechanism in the maintenance of cooperation among unrelated individuals. Indirect reciprocity leads to conditional cooperation according to social norms that discriminate the good (those who deserve to be rewarded with help) and the bad (those who should be punished by refusal of help). Despite intensive research, however, there is no definitive consensus on what social norms best promote cooperation through indirect reciprocity, and it remains unclear even how those who refuse to help the bad should be assessed. Here, we propose a new simple norm called “Staying” that prescribes abstaining from assessment. Under the Staying norm, the image of the person who makes the decision to give help stays the same as in the last assessment if the person on the receiving end has a bad image. In this case, the choice about whether or not to give help to the potential receiver does not affect the image of the potential giver. We analyze the Staying norm in terms of evolutionary game theory and demonstrate that Staying is most effective in establishing cooperation compared to the prevailing social norms, which rely on constant monitoring and unconditional assessment. The application of Staying suggests that the strict application of moral judgment is limited. PMID:28150808

The evolution of conditional moral assessment in indirect reciprocity.

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Sasaki, Tatsuya; Okada, Isamu; Nakai, Yutaka

2017-02-02

Indirect reciprocity is a major mechanism in the maintenance of cooperation among unrelated individuals. Indirect reciprocity leads to conditional cooperation according to social norms that discriminate the good (those who deserve to be rewarded with help) and the bad (those who should be punished by refusal of help). Despite intensive research, however, there is no definitive consensus on what social norms best promote cooperation through indirect reciprocity, and it remains unclear even how those who refuse to help the bad should be assessed. Here, we propose a new simple norm called "Staying" that prescribes abstaining from assessment. Under the Staying norm, the image of the person who makes the decision to give help stays the same as in the last assessment if the person on the receiving end has a bad image. In this case, the choice about whether or not to give help to the potential receiver does not affect the image of the potential giver. We analyze the Staying norm in terms of evolutionary game theory and demonstrate that Staying is most effective in establishing cooperation compared to the prevailing social norms, which rely on constant monitoring and unconditional assessment. The application of Staying suggests that the strict application of moral judgment is limited.

The evolution of conditional moral assessment in indirect reciprocity

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Sasaki, Tatsuya; Okada, Isamu; Nakai, Yutaka

2017-02-01

Indirect reciprocity is a major mechanism in the maintenance of cooperation among unrelated individuals. Indirect reciprocity leads to conditional cooperation according to social norms that discriminate the good (those who deserve to be rewarded with help) and the bad (those who should be punished by refusal of help). Despite intensive research, however, there is no definitive consensus on what social norms best promote cooperation through indirect reciprocity, and it remains unclear even how those who refuse to help the bad should be assessed. Here, we propose a new simple norm called “Staying” that prescribes abstaining from assessment. Under the Staying norm, the image of the person who makes the decision to give help stays the same as in the last assessment if the person on the receiving end has a bad image. In this case, the choice about whether or not to give help to the potential receiver does not affect the image of the potential giver. We analyze the Staying norm in terms of evolutionary game theory and demonstrate that Staying is most effective in establishing cooperation compared to the prevailing social norms, which rely on constant monitoring and unconditional assessment. The application of Staying suggests that the strict application of moral judgment is limited.

Indirect Reciprocity with Optional Interactions and Private Information

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Jason Olejarz

2015-09-01

Full Text Available We consider indirect reciprocity with optional interactions and private information. A game is offered between two players and accepted unless it is known that the other person is a defector. Whenever a defector manages to exploit a cooperator, his or her reputation is revealed to others in the population with some probability. Therefore, people have different private information about the reputation of others, which is a setting that is difficult to analyze in the theory of indirect reciprocity. Since a defector loses a fraction of his social ties each time he exploits a cooperator, he is less efficient at exploiting cooperators in subsequent rounds. We analytically calculate the critical benefit-to-cost ratio above which cooperation is successful in various settings. We demonstrate quantitative agreement with simulation results of a corresponding Wright–Fisher process with optional interactions and private information. We also deduce a simple necessary condition for the critical benefit-to-cost ratio.

The Development of Theory of Mind and Positive and Negative Reciprocity in Preschool Children.

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Schug, Joanna; Takagishi, Haruto; Benech, Catalina; Okada, Hiroyuki

2016-01-01

This study examined the relation between the acquisition of false-beliefs theory of mind (ToM) and reciprocity in preschoolers. Preschool-aged children completed a task assessing the understanding of false beliefs, and played an Ultimatum Game (UG) with another child in a face-to-face setting. Negative reciprocity was assessed by examining the rejection of unfair offers made by another child in the UG, while positive reciprocity was assessed by examining allocations made by participants in a Dictator Game (DG) following the UG. The results indicated that children who had passed a task assessing first-order false beliefs were more likely to make generous offers in a DG following a fair offer made by their partner in a proceeding UG, but that false beliefs ToM was unrelated to the rejection of unfair offers in the UG.

Partner Choice Drives the Evolution of Cooperation via Indirect Reciprocity.

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Gilbert Roberts

Full Text Available Indirect reciprocity potentially provides an important means for generating cooperation based on helping those who help others. However, the use of 'image scores' to summarize individuals' past behaviour presents a dilemma: individuals withholding help from those of low image score harm their own reputation, yet giving to defectors erodes cooperation. Explaining how indirect reciprocity could evolve has therefore remained problematic. In all previous treatments of indirect reciprocity, individuals are assigned potential recipients and decide whether to cooperate or defect based on their reputation. A second way of achieving discrimination is through partner choice, which should enable individuals to avoid defectors. Here, I develop a model in which individuals choose to donate to anyone within their group, or to none. Whereas image scoring with random pairing produces cycles of cooperation and defection, with partner choice there is almost maximal cooperation. In contrast to image scoring with random pairing, partner choice results in almost perfect contingency, producing the correlation between giving and receiving required for cooperation. In this way, partner choice facilitates much higher and more stable levels of cooperation through image scoring than previously reported and provides a simple mechanism through which systems of helping those who help others can work.

Ingroup favoritism and intergroup cooperation under indirect reciprocity based on group reputation.

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Masuda, Naoki

2012-10-21

Indirect reciprocity in which players cooperate with unacquainted other players having good reputations is a mechanism for cooperation in relatively large populations subjected to social dilemma situations. When the population has group structure, as is often found in social networks, players in experiments are considered to show behavior that deviates from existing theoretical models of indirect reciprocity. First, players often show ingroup favoritism (i.e., cooperation only within the group) rather than full cooperation (i.e., cooperation within and across groups), even though the latter is Pareto efficient. Second, in general, humans approximate outgroup members' personal characteristics, presumably including the reputation used for indirect reciprocity, by a single value attached to the group. Humans use such a stereotypic approximation, a phenomenon known as outgroup homogeneity in social psychology. I propose a model of indirect reciprocity in populations with group structure to examine the possibility of ingroup favoritism and full cooperation. In accordance with outgroup homogeneity, I assume that players approximate outgroup members' personal reputations by a single reputation value attached to the group. I show that ingroup favoritism and full cooperation are stable under different social norms (i.e., rules for assigning reputations) such that they do not coexist in a single model. If players are forced to consistently use the same social norm for assessing different types of interactions (i.e., ingroup versus outgroup interactions), only full cooperation survives. The discovered mechanism is distinct from any form of group selection. The results also suggest potential methods for reducing ingroup bias to shift the equilibrium from ingroup favoritism to full cooperation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Selective Cooperation in the Supermarket : Field Experimental Evidence for Indirect Reciprocity.

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Lange, Florian; Eggert, Frank

2015-12-01

Numerous laboratory experiments suggest that mechanisms of indirect reciprocity might account for human cooperation. However, conclusive field data supporting the predictions of indirect reciprocity in everyday life situations is still scarce. Here, we attempt to compensate for this lack by examining the determinants of cooperative behavior in a German supermarket. Our methods were as follows: Confederates of the experimenter lined up at the checkout, apparently to buy a single item. As an act of cooperation, the waiting person in front (the potential helper) could allow the confederate to go ahead. By this means, the potential helper could take a cost (additional waiting time) by providing the confederate with a benefit (saved waiting time). We recorded the potential helpers' behavior and the number of items they purchased as a quantitative measure proportional to the confederate's benefit. Moreover, in a field experimental design, we varied the confederates' image by manipulating the item they purchased (beer vs. water). As predicted, the more waiting time they could save, the more likely the confederates were to receive cooperation. This relationship was moderated by the confederates' image. Cost-to-benefit ratios were required to be more favorable for beer-purchasing individuals to receive cooperation. Our results demonstrate that everyday human cooperation can be studied unobtrusively in the field and that cooperation among strangers is selective in a way that is consistent with current models of indirect reciprocity.

Indirect reciprocity and strategic reputation building in an experimental helping game

Czech Academy of Sciences Publication Activity Database

Engelmann, Dirk; Fischbacher, U.

2009-01-01

Roč. 67, č. 2 (2009), s. 399-407 ISSN 0899-8256 Institutional research plan: CEZ:AV0Z70850503 Keywords : indirect reciprocity * reputation * experimental economics Subject RIV: AH - Economics Impact factor: 1.239, year: 2009

Five-Year-Old Preschoolers' Sharing is Influenced by Anticipated Reciprocation.

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Xiong, Mingrui; Shi, Jiannong; Wu, Zhen; Zhang, Zhen

2016-01-01

Whether children share in anticipation of future benefits returned by a partner is an interesting question. In this study, 5-year-old children and an adult partner played a sharing game, in which children donated first and the partner donated afterward. In Experiment 1, the partner's resources were more attractive than the child's. In the reciprocal condition, the child was told that s/he would be a recipient when the partner played as a donor. In the non-reciprocal condition, however, the child was told that an anonymous child would be the recipient when the partner donated. Results showed that children shared more with the partner when they knew that they would be a recipient later. In Experiment 2, the child was always the recipient when the partner donated, but the partner's resources were more desirable than the child's in the high-value condition, and less desirable in the low-value condition. We found that children were more generous when the partner's resources were valued higher. These findings demonstrate that 5-year-old preschoolers' sharing choices take into account the anticipated reciprocity of the recipient, suggesting either self-interested tactical sharing or direct reciprocity in advance of receiving. Specifically, they adjust their sharing behavior depending on whether a partner has the potential to reciprocate, and whether it is worth sharing relative to the value of the payback.

The price of being seen to be just: an intention signalling strategy for indirect reciprocity.

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Tanaka, Hiroki; Ohtsuki, Hisashi; Ohtsubo, Yohsuke

2016-07-27

Cooperation among strangers is a marked characteristic of human sociality. One prominent evolutionary explanation for this form of human cooperation is indirect reciprocity, whereby each individual selectively helps people with a 'good' reputation, but not those with a 'bad' reputation. Some evolutionary analyses have underscored the importance of second-order reputation information (the reputation of a current partner's previous partner) for indirect reciprocity as it allows players to discriminate justified 'good' defectors, who selectively deny giving help to 'bad' partners, from unjustified 'bad' defectors. Nevertheless, it is not clear whether people in fact make use of second-order information in indirect reciprocity settings. As an alternative, we propose the intention signalling strategy, whereby defectors are given the option to abandon a resource as a means of expunging their 'bad' reputation. Our model deviates from traditional modelling approaches in the indirect reciprocity literature in a crucial way-we show that first-order information is sufficient to maintain cooperation if players are given an option to signal their intention. Importantly, our model is robust against invasion by both unconditionally cooperative and uncooperative strategies, a first step towards demonstrating its viability as an evolutionarily stable strategy. Furthermore, in two behavioural experiments, when participants were given the option to abandon a resource so as to mend a tarnished reputation, participants not only spontaneously began to use this option, they also interpreted others' use of this option as a signal of cooperative intent. © 2016 The Author(s).

A Dominant Social Comparison Heuristic Unites Alternative Mechanisms for the Evolution of Indirect Reciprocity

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Whitaker, Roger M.; Colombo, Gualtiero B.; Allen, Stuart M.; Dunbar, Robin I. M.

2016-08-01

Cooperation is a fundamental human trait but our understanding of how it functions remains incomplete. Indirect reciprocity is a particular case in point, where one-shot donations are made to unrelated beneficiaries without any guarantee of payback. Existing insights are largely from two independent perspectives: i) individual-level cognitive behaviour in decision making, and ii) identification of conditions that favour evolution of cooperation. We identify a fundamental connection between these two areas by examining social comparison as a means through which indirect reciprocity can evolve. Social comparison is well established as an inherent human disposition through which humans navigate the social world by self-referential evaluation of others. Donating to those that are at least as reputable as oneself emerges as a dominant heuristic, which represents aspirational homophily. This heuristic is found to be implicitly present in the current knowledge of conditions that favour indirect reciprocity. The effective social norms for updating reputation are also observed to support this heuristic. We hypothesise that the cognitive challenge associated with social comparison has contributed to cerebral expansion and the disproportionate human brain size, consistent with the social complexity hypothesis. The findings have relevance for the evolution of autonomous systems that are characterised by one-shot interactions.

A norm knockout method on indirect reciprocity to reveal indispensable norms

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Yamamoto, Hitoshi; Okada, Isamu; Uchida, Satoshi; Sasaki, Tatsuya

2017-03-01

Although various norms for reciprocity-based cooperation have been suggested that are evolutionarily stable against invasion from free riders, the process of alternation of norms and the role of diversified norms remain unclear in the evolution of cooperation. We clarify the co-evolutionary dynamics of norms and cooperation in indirect reciprocity and also identify the indispensable norms for the evolution of cooperation. Inspired by the gene knockout method, a genetic engineering technique, we developed the norm knockout method and clarified the norms necessary for the establishment of cooperation. The results of numerical investigations revealed that the majority of norms gradually transitioned to tolerant norms after defectors are eliminated by strict norms. Furthermore, no cooperation emerges when specific norms that are intolerant to defectors are knocked out.

Reciprocity Between Parental Psychopathology and Oppositional Symptoms From Preschool to Middle Childhood.

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Antúnez, Zayra; de la Osa, Nuria; Granero, Roser; Ezpeleta, Lourdes

2018-03-01

Oppositional defiant disorder (ODD) is a common disorder in preschool children. Evidence indicates that maternal and paternal psychopathology, particularly aggressive behavior and anxious and depressed symptoms, contributes to the development of this disorder. The latest research also suggests that ODD symptoms may exacerbate the mental health problems of parents. Our aim was to establish the existence of a reciprocal association between paternal and maternal psychopathology (aggression, depression, and anxiety) and child ODD at ages 3 and 8, using a longitudinal design in a community sample of preschoolers. The sample included 331 children evaluated at ages 3 and 8 through questionnaires and a semistructured diagnostic interview with parents. Parents also informed about their own psychopathology. At 3 years of age, higher levels of ODD symptoms in girls were concurrently associated with maternal anxious and depressed symptoms and paternal aggressive behavior, and higher levels of ODD symptoms in boys were concurrently associated with maternal aggressive behavior. Longitudinally, for boys, higher levels of maternal anxious and depressed symptoms at child age 3 predicted increases in ODD symptoms from 3 to 8 years of age. In addition, higher levels of ODD symptoms in boys aged 3-8 years predicted increases in fathers' anxious and depressive symptoms. Children with ODD should be evaluated and treated promptly, but efforts should be extended to their parents. Mothers' and fathers' mental health must be explored because the psychopathologies of children and parents reciprocally affect each other. © 2017 Wiley Periodicals, Inc.

Altruism and Indirect Reciprocity: The Interaction of Person and Situation in Prosocial Behavior

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Simpson, Brent; Willer, Robb

2008-01-01

A persistent puzzle in the social and biological sciences is the existence of prosocial behavior, actions that benefit others, often at a cost to oneself. Recent theoretical models and empirical studies of indirect reciprocity show that actors behave prosocially in order to develop an altruistic reputation and receive future benefits from third…

Stern-judging: A simple, successful norm which promotes cooperation under indirect reciprocity.

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Pacheco, Jorge M; Santos, Francisco C; Chalub, Fabio A C C

2006-12-29

We study the evolution of cooperation under indirect reciprocity, believed to constitute the biological basis of morality. We employ an evolutionary game theoretical model of multilevel selection, and show that natural selection and mutation lead to the emergence of a robust and simple social norm, which we call stern-judging. Under stern-judging, helping a good individual or refusing help to a bad individual leads to a good reputation, whereas refusing help to a good individual or helping a bad one leads to a bad reputation. Similarly for tit-for-tat and win-stay-lose-shift, the simplest ubiquitous strategies in direct reciprocity, the lack of ambiguity of stern-judging, where implacable punishment is compensated by prompt forgiving, supports the idea that simplicity is often associated with evolutionary success.

Stern-judging: A simple, successful norm which promotes cooperation under indirect reciprocity.

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Jorge M Pacheco

2006-12-01

Full Text Available We study the evolution of cooperation under indirect reciprocity, believed to constitute the biological basis of morality. We employ an evolutionary game theoretical model of multilevel selection, and show that natural selection and mutation lead to the emergence of a robust and simple social norm, which we call stern-judging. Under stern-judging, helping a good individual or refusing help to a bad individual leads to a good reputation, whereas refusing help to a good individual or helping a bad one leads to a bad reputation. Similarly for tit-for-tat and win-stay-lose-shift, the simplest ubiquitous strategies in direct reciprocity, the lack of ambiguity of stern-judging, where implacable punishment is compensated by prompt forgiving, supports the idea that simplicity is often associated with evolutionary success.

Stochasticity in economic losses increases the value of reputation in indirect reciprocity.

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dos Santos, Miguel; Placì, Sarah; Wedekind, Claus

2015-12-14

Recent theory predicts harsh and stochastic conditions to generally promote the evolution of cooperation. Here, we test experimentally whether stochasticity in economic losses also affects the value of reputation in indirect reciprocity, a type of cooperation that is very typical for humans. We used a repeated helping game with observers. One subject (the "Unlucky") lost some money, another one (the "Passer-by") could reduce this loss by accepting a cost to herself, thereby building up a reputation that could be used by others in later interactions. The losses were either stable or stochastic, but the average loss over time and the average efficiency gains of helping were kept constant in both treatments. We found that players with a reputation of being generous were generally more likely to receive help by others, such that investing into a good reputation generated long-term benefits that compensated for the immediate costs of helping. Helping frequencies were similar in both treatments, but players with a reputation to be selfish lost more resources under stochastic conditions. Hence, returns on investment were steeper when losses varied than when they did not. We conclude that this type of stochasticity increases the value of reputation in indirect reciprocity.

Direct versus indirect treatment for preschool children who stutter: The RESTART randomized trial

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C. de Sonneville (Caroline); E.A. Stolk (Elly); T. Rietveld (Toni); M.-C. Franken (Marie-Christine)

2015-01-01

textabstractObjective Stuttering is a common childhood disorder. There is limited high quality evidence regarding options for best treatment. The aim of the study was to compare the effectiveness of direct treatment with indirect treatment in preschool children who stutter. Methods In this

Self-Punishment Promotes Forgiveness in the Direct and Indirect Reciprocity Contexts.

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Zhu, Ruida; Shen, Xueyi; Tang, Honghong; Ye, Peixia; Wang, Huagen; Mai, Xiaoqin; Liu, Chao

2017-06-01

Most previous studies regarding self-punishment have focused on the correlation between moral emotion and self-punishment. Only a few studies have attempted to understand self-punishment from the perspective of seeking forgiveness, and no study has yet directly tested whether wrongdoers' self-punishment promotes others to forgive the wrongdoers. In three studies, the participants judged the wrongdoers' self-punishment behaviors following an unfair allocation and reported the extent to which they forgave the wrongdoers. The results demonstrated that self-punishment did promote forgiveness in both the direct (Studies 1 and 2) and indirect reciprocity (Study 3) contexts. Consistent with costly signaling theory, the costlier the self-punishment was, the stronger the effect it had on forgiveness. Moreover, communicative self-punishment had a better effect than silent self-punishment when the cost was relatively high in the direct-reciprocity studies. These findings can guide us regarding how to address a damaged relationship via self-punishment when compensation is not feasible or acceptable.

Tolerant indirect reciprocity can boost social welfare through solidarity with unconditional cooperators in private monitoring.

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Okada, Isamu; Sasaki, Tatsuya; Nakai, Yutaka

2017-08-29

Indirect reciprocity is an important mechanism for resolving social dilemmas. Previous studies explore several types of assessment rules that are evolutionarily stable for keeping cooperation regimes. However, little is known about the effects of private information on social systems. Most indirect reciprocity studies assume public monitoring in which individuals share a single assessment for each individual. Here, we consider a private monitoring system that loosens such an unnatural assumption. We explore the stable norms in the private system using an individual-based simulation. We have three main findings. First, narrow and unstable cooperation: cooperation in private monitoring becomes unstable and the restricted norms cannot maintain cooperative regimes while they can in public monitoring. Second, stable coexistence of discriminators and unconditional cooperators: under private monitoring, unconditional cooperation can play a role in keeping a high level of cooperation in tolerant norm situations. Finally, Pareto improvement: private monitoring can achieve a higher cooperation rate than does public monitoring.

Attentional fluctuations in preschoolers: Direct and indirect relations with task accuracy, academic readiness, and school performance.

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Isbell, Elif; Calkins, Susan D; Swingler, Margaret M; Leerkes, Esther M

2018-03-01

Attentional control fluctuates in the presence of internal and external distractors, wandering on and off a given task. The current study investigated individual differences in attentional fluctuations in 250 preschoolers. Attentional fluctuations were assessed via intra-individual variability in response time in a Go/No-Go task. Greater fluctuations in attentional control were linked to lower task accuracy. In addition, greater attentional fluctuations predicted lower performance in a task of cognitive flexibility, the Dimensional Change Card Sort task. Attentional fluctuations were also associated with laboratory measures of academic readiness in preschool, as assessed by the Applied Problems and Letter-Word Identification subscales of the Woodcock-Johnson III Tests of Achievement, which in turn predicted teacher reports of academic performance in first grade. Attentional fluctuations also had indirect associations with emergent math skills in preschool, via cognitive flexibility, as well as indirect associations with first-grade teacher reports of academic performance, via the relations between cognitive flexibility and emergent math skills in preschool. These results suggest that consistency is an important aspect of attentional control during early childhood. Copyright © 2017 Elsevier Inc. All rights reserved.

The Development of a Scientific Motive: How Preschool Science and Home Play Reciprocally Contribute to Science Learning

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Gomes, Judith; Fleer, Marilyn

2017-07-01

There are a growing number of studies that have examined science learning for preschool children. Some research has looked into children's home experiences and some has focused on transition, practices, routines, and traditions in preschool contexts. However, little attention has been directed to the relationship between children's learning experiences at preschool and at home, and how this relationship can assist in the development of science concepts relevant to everyday life. In drawing upon Hedegaard's (Learning and child development, 2002) cultural-historical conception of motives and Vygotsky's (The collected works of L.S. Vygotsky: problems of general psychology, 1987) theory of everyday and scientific concept formation, the study reported in this paper examines one child, Jimmy (4.2 years), and his learning experiences at home and at preschool. Data gathering featured the video recording of 4 weeks of Jimmy's learning in play at home and at preschool (38.5 h), parent questionnaire and interviews, and researcher and family gathered video observations of home play with his parents (3.5 h). Findings show how a scientific motive develops through playful everyday learning moments at home and at preschool when scientific play narratives and resources are aligned. The study contributes to a more nuanced understanding of the science learning of young children and a conception of pedagogy that takes into account the reciprocity of home and school contexts for learning science.

Predictors of Social Skills for Preschool Children at Risk for ADHD: The Relationship between Direct and Indirect Measurements

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Thomas, Lisa B.; Shapiro, Edward S.; DuPaul, George J.; Lutz, J. Gary; Kern, Lee

2011-01-01

The relationship between direct and indirect measurements of social skills and social problem behaviors for preschool children at risk for attention deficit hyperactivity disorder (ADHD) was examined. Participants included 137 preschool children, aged 3 to 5 years, at risk for ADHD, who were participating in a larger study examining the effects of…

Giving Is Nicer than Taking: Preschoolers Reciprocate Based on the Social Intentions of the Distributor.

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Martina Vogelsang

Full Text Available Recent research has found that even preschoolers give more resources to others who have previously given resources to them, but the psychological bases of this reciprocity are unknown. In our study, a puppet distributed resources between herself and a child by taking some from a pile in front of the child or else by giving some from a pile in front of herself. Although the resulting distributions were identical, three- and five-year-olds reciprocated less generously when the puppet had taken rather than given resources. This suggests that children's judgments about resource distribution are more about the social intentions of the distributor and the social framing of the distributional act than about the amount of resources obtained. In order to rule out that the differences in the children's reciprocal behavior were merely due to experiencing gains and losses, we conducted a follow-up study. Here, three- and-five year olds won or lost resources in a lottery draw and could then freely give or take resources to/from a puppet, respectively. In this study, they did not respond differently after winning vs. losing resources.

Two wrongs don't make a right: the initial viability of different assessment rules in the evolution of indirect reciprocity.

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Panchanathan, Karthik

2011-05-21

Indirect reciprocity models are meant to correspond to simple moral systems, in which individuals assess the interactions of third parties in order to condition their cooperative behavior. Despite the staggering number of possible assessment rules in even the simplest of these models, previous research suggests that only a handful are evolutionarily stable against invasion by free riders. These successful assessment rules fall into two categories, one which positively judges miscreants when they refuse to help other miscreants, the other which does not. Previous research has not, however, demonstrated that all of these rules can invade an asocial population--a requirement for a complete theory of social evolution. Here, I present a general analytical model of indirect reciprocity and show that the class of assessment rules which positively judges a refusal to help scofflaws cannot invade a population of defectors, whereas the other class can. When rare, assessment rules which positively judge a refusal to help bad people produce a poor correlation between reputation and behavior. It is this correlation that generates the assortment crucial in sustaining cooperation through indirect reciprocity. Only assessment rules that require good deeds to achieve a good reputation guarantee a strong correlation between behavior and reputation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Indirect reciprocity with negative assortment and limited information can promote cooperation.

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Brush, Eleanor; Brännström, Åke; Dieckmann, Ulf

2018-04-14

Cooperation is ubiquitous in biological and social systems, even though cooperative behavior is often costly and at risk of exploitation by non-cooperators. Several studies have demonstrated that indirect reciprocity, whereby some members of a group observe the behaviors of their peers and use this information to discriminate against previously uncooperative agents in the future, can promote prosocial behavior. Some studies have shown that differential propensities of interacting among and between different types of agents (interaction assortment) can increase the effectiveness of indirect reciprocity. No previous studies have, however, considered differential propensities of observing the behaviors of different types of agents (information assortment). Furthermore, most previous studies have assumed that discriminators possess perfect information about others and incur no costs for gathering and storing this information. Here, we (1) consider both interaction assortment and information assortment, (2) assume discriminators have limited information about others, and (3) introduce a cost for information gathering and storage, in order to understand how the ability of discriminators to stabilize cooperation is affected by these steps toward increased realism. We report the following findings. First, cooperation can persist when agents preferentially interact with agents of other types or when discriminators preferentially observe other discriminators, even when they have limited information. Second, contrary to intuition, increasing the amount of information available to discriminators can exacerbate defection. Third, introducing costs of gathering and storing information makes it more difficult for discriminators to stabilize cooperation. Our study is one of only a few studies to date that show how negative interaction assortment can promote cooperation and broadens the set of circumstances in which it is know that cooperation can be maintained. Copyright © 2018

Direct versus Indirect Treatment for Preschool Children who Stutter: The RESTART Randomized Trial.

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Caroline de Sonneville-Koedoot

Full Text Available Stuttering is a common childhood disorder. There is limited high quality evidence regarding options for best treatment. The aim of the study was to compare the effectiveness of direct treatment with indirect treatment in preschool children who stutter.In this multicenter randomized controlled trial with an 18 month follow-up, preschool children who stutter who were referred for treatment were randomized to direct treatment (Lidcombe Program; n = 99 or indirect treatment (RESTART-DCM treatment; n = 100. Main inclusion criteria were age 3-6 years, ≥3% syllables stuttered (%SS, and time since onset ≥6 months. The primary outcome was the percentage of non-stuttering children at 18 months. Secondary outcomes included stuttering frequency (%SS, stuttering severity ratings by the parents and therapist, severity rating by the child, health-related quality of life, emotional and behavioral problems, and speech attitude.Percentage of non-stuttering children for direct treatment was 76.5% (65/85 versus 71.4% (65/91 for indirect treatment (Odds Ratio (OR, 0.6; 95% CI, 0.1-2.4, p = .42. At 3 months, children treated by direct treatment showed a greater decline in %SS (significant interaction time x therapy: β = -1.89; t(282.82 = -2.807, p = .005. At 18 months, stuttering frequency was 1.2% (SD 2.1 for direct treatment and 1.5% (SD 2.1 for indirect treatment. Direct treatment had slightly better scores on most other secondary outcome measures, but no differences between treatment approaches were significant.Direct treatment decreased stuttering more quickly during the first three months of treatment. At 18 months, however, clinical outcomes for direct and indirect treatment were comparable. These results imply that at 18 months post treatment onset, both treatments are roughly equal in treating developmental stuttering in ways that surpass expectations of natural recovery. Follow-up data are needed to confirm these findings in the longer term

Evolution of gossip-based indirect reciprocity on a bipartite network

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Giardini, Francesca; Vilone, Daniele

2016-11-01

Cooperation can be supported by indirect reciprocity via reputation. Thanks to gossip, reputations are built and circulated and humans can identify defectors and ostracise them. However, the evolutionary stability of gossip is allegedly undermined by the fact that it is more error-prone that direct observation, whereas ostracism could be ineffective if the partner selection mechanism is not robust. The aim of this work is to investigate the conditions under which the combination of gossip and ostracism might support cooperation in groups of different sizes. We are also interested in exploring the extent to which errors in transmission might undermine the reliability of gossip as a mechanism for identifying defectors. Our results show that a large quantity of gossip is necessary to support cooperation, and that group structure can mitigate the effects of errors in transmission.

Evolution of gossip-based indirect reciprocity on a bipartite network.

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Giardini, Francesca; Vilone, Daniele

2016-11-25

Cooperation can be supported by indirect reciprocity via reputation. Thanks to gossip, reputations are built and circulated and humans can identify defectors and ostracise them. However, the evolutionary stability of gossip is allegedly undermined by the fact that it is more error-prone that direct observation, whereas ostracism could be ineffective if the partner selection mechanism is not robust. The aim of this work is to investigate the conditions under which the combination of gossip and ostracism might support cooperation in groups of different sizes. We are also interested in exploring the extent to which errors in transmission might undermine the reliability of gossip as a mechanism for identifying defectors. Our results show that a large quantity of gossip is necessary to support cooperation, and that group structure can mitigate the effects of errors in transmission.

Intermediaries in Trust: Indirect Reciprocity, Incentives, and Norms

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Giangiacomo Bravo

2015-01-01

Full Text Available Any trust situation involves a certain amount of risk for trustors that trustees could abuse. In some cases, intermediaries exist who play a crucial role in the exchange by providing reputational information. To examine under what conditions intermediary opinion could have a positive impact on cooperation, we designed two experiments based on a modified version of the investment game where intermediaries rated the behaviour of trustees under various incentive schemes and different role structures. We found that intermediaries can increase trust if there is room for indirect reciprocity between the involved parties. We also found that the effect of monetary incentives and social norms cannot be clearly separable in these situations. If properly designed, monetary incentives for intermediaries can have a positive effect. On the one hand, when intermediary rewards are aligned with the trustor’s interest, investments and returns tend to increase. On the other hand, fixed monetary incentives perform less than any other incentive schemes and endogenous social norms in ensuring trust and fairness. These findings should make us reconsider the mantra of incentivization of social and public conventional policy.

Parent-specific reciprocity from infancy to adolescence shapes children's social competence and dialogical skills.

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Feldman, Ruth; Bamberger, Esther; Kanat-Maymon, Yaniv

2013-01-01

Reciprocity - the capacity to engage in social exchange that integrates inputs from multiple partners into a unified social event - is a cornerstone of adaptive social life that is learned within dyad-specific attachments during an early period of neuroplasticity. Yet, very little research traced the expression of children's reciprocity with their mother and father in relation to long-term outcomes. Guided by evolutionary models, we followed mothers, fathers, and their firstborn child longitudinally and observed mother-child and father-child reciprocity in infancy, preschool, and adolescence. In preschool, children's social competence, aggression, and prosocial behavior were observed at kindergarten. In adolescence, children's dialogical skills were assessed during positive and conflict interactions with same-sex best friends. Father-child and mother-child reciprocity were individually stable, inter-related at each stage, and consisted of distinct behavioral components. Structural equation modeling indicated that early maternal and paternal reciprocity were each uniquely predictive of social competence and lower aggression in preschool, which, in turn, shaped dialogical skills in adolescence. Father-adolescent reciprocity contributed to the dialogical negotiation of conflict, whereas mother-adolescent reciprocity predicted adolescents' dialogical skills during positive exchanges. Results highlight the role of parent-child reciprocity in shaping children's social collaboration and intimate relationships with non-kin members of their social world.

Cardiac vagal regulation in infancy predicts executive function and social competence in preschool: Indirect effects through language.

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Whedon, Margaret; Perry, Nicole B; Calkins, Susan D; Bell, Martha A

2018-05-21

Parasympathetic nervous system functioning in infancy may serve a foundational role in the development of cognitive and socioemotional skills (Calkins, 2007). In this study (N = 297), we investigated the potential indirect effects of cardiac vagal regulation in infancy on children's executive functioning and social competence in preschool via expressive and receptive language in toddlerhood. Vagal regulation was assessed at 10 months during two attention conditions (social, nonsocial) via task-related changes in respiratory sinus arrhythmia (RSA). A path analysis revealed that decreased RSA from baseline in the nonsocial condition and increased RSA in the social condition were related to larger vocabularies in toddlerhood. Additionally, children's vocabulary sizes were positively related to their executive function and social competence in preschool. Indirect effects from vagal regulation in both contexts to both 4-year outcomes were significant, suggesting that early advances in language may represent a mechanism through which biological functioning in infancy impacts social and cognitive functioning in childhood. © 2018 Wiley Periodicals, Inc.

Evolutionary stability and resistance to cheating in an indirect reciprocity model based on reputation

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Martinez-Vaquero, Luis A.; Cuesta, José A.

2013-05-01

Indirect reciprocity is one of the main mechanisms to explain the emergence and sustainment of altruism in societies. The standard approach to indirect reciprocity is reputation models. These are games in which players base their decisions on their opponent's reputation gained in past interactions with other players (moral assessment). The combination of actions and moral assessment leads to a large diversity of strategies; thus determining the stability of any of them against invasions by all the others is a difficult task. We use a variant of a previously introduced reputation-based model that let us systematically analyze all these invasions and determine which ones are successful. Accordingly, we are able to identify the third-order strategies (those which, apart from the action, judge considering both the reputation of the donor and that of the recipient) that are evolutionarily stable. Our results reveal that if a strategy resists the invasion of any other one sharing its same moral assessment, it can resist the invasion of any other strategy. However, if actions are not always witnessed, cheaters (i.e., individuals with a probability of defecting regardless of the opponent's reputation) have a chance to defeat the stable strategies for some choices of the probabilities of cheating and of being witnessed. Remarkably, by analyzing this issue with adaptive dynamics we find that whether an honest population resists the invasion of cheaters is determined by a Hamilton-like rule, with the probability that the cheat is discovered playing the role of the relatedness parameter.

Transient nature of cooperation by pay-it-forward reciprocity.

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Horita, Yutaka; Takezawa, Masanori; Kinjo, Takuji; Nakawake, Yo; Masuda, Naoki

2016-01-20

Humans often forward kindness received from others to strangers, a phenomenon called the upstream or pay-it-forward indirect reciprocity. Some field observations and laboratory experiments found evidence of pay-it-forward reciprocity in which chains of cooperative acts persist in social dilemma situations. Theoretically, however, cooperation based on pay-it-forward reciprocity is not sustainable. We carried out laboratory experiments of a pay-it-forward indirect reciprocity game (i.e., chained gift-giving game) on a large scale in terms of group size and time. We found that cooperation consistent with pay-it-forward reciprocity occurred only in a first few decisions per participant and that cooperation originated from inherent pro-sociality of individuals. In contrast, the same groups of participants showed persisting chains of cooperation in a different indirect reciprocity game in which participants earned reputation by cooperating. Our experimental results suggest that pay-it-forward reciprocity is transient and disappears when a person makes decisions repeatedly, whereas the reputation-based reciprocity is stable in the same situation.

Cooperation enhanced by indirect reciprocity in spatial prisoner's dilemma games for social P2P systems

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Tian, Lin-Lin; Li, Ming-Chu; Wang, Zhen

2016-11-01

With the growing interest in social Peer-to-Peer (P2P) applications, relationships of individuals are further exploited to improve the performances of reputation systems. It is an on-going challenge to investigate how spatial reciprocity aids indirect reciprocity in sustaining cooperation in practical P2P environments. This paper describes the construction of an extended prisoner's dilemma game on square lattice networks with three strategies, i.e., defection, unconditional cooperation, and reciprocal cooperation. Reciprocators discriminate partners according to their reputations based on image scoring, where mistakes in judgment of reputations may occur. The independent structures of interaction and learning neighborhood are discussed, with respect to the situation in which learning environments differ from interaction networks. The simulation results have indicated that the incentive mechanism enhances cooperation better in structured peers than among a well-mixed population. Given the realistic condition of inaccurate reputation scores, defection is still successfully held down when the players interact and learn within the unified neighborhoods. Extensive simulations have further confirmed the positive impact of spatial structure on cooperation with different sizes of lattice neighborhoods. And similar conclusions can also be drawn on regular random networks and scale-free networks. Moreover, for the separated structures of the neighborhoods, the interaction network has a critical effect on the evolution dynamics of cooperation and learning environments only have weaker impacts on the process. Our findings further provide some insights concerning the evolution of collective behaviors in social systems.

Predicting and detecting reciprocity between indirect ecological interactions and evolution.

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Estes, James A; Brashares, Justin S; Power, Mary E

2013-05-01

Living nature can be thought of as a tapestry, defined not only by its constituent parts but also by how these parts are woven together. The weaving of this tapestry is a metaphor for species interactions, which can be divided into three broad classes: competitive, mutualistic, and consumptive. Direct interactions link together as more complex networks, for example, the joining of consumptive interactions into food webs. Food web dynamics are driven, in turn, by changes in the abundances of web members, whose numbers or biomass respond to bottom-up (resource limitation) and top-down (consumer limitation) forcing. The relative strengths of top-down and bottom-up forcing on the abundance of a given web member depend on its ecological context, including its topological position within the food web. Top-down effects by diverse consumers are nearly ubiquitous, in many cases influencing the structure and operation of ecosystems. While the ecological effects of such interactions are well known, far less is known of their evolutionary consequences. In this essay, we describe sundry consequences of these interaction chains on species and ecosystem processes, explain several known or suspected evolutionary effects of consumer-induced interaction chains, and identify areas where reciprocity between ecology and evolution involving the indirect effects of consumer-prey interaction chains might be further explored.

Evolution of cooperation under indirect reciprocity and arbitrary exploration rates

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Santos, Fernando P.; Pacheco, Jorge M.; Santos, Francisco C.

2016-11-01

Cooperation has been recognized as an evolutionary puzzle since Darwin, and remains identified as one of the biggest challenges of the XXIst century. Indirect Reciprocity (IR), a key mechanism that humans employ to cooperate with each other, establishes that individual behaviour depends on reputations, which in turn evolve depending on social norms that classify behaviours as good or bad. While it is well known that different social norms give rise to distinct cooperation levels, it remains unclear how the performance of each norm is influenced by the random exploration of new behaviours, often a key component of social dynamics where a plethora of stimuli may compel individuals to deviate from pre-defined behaviours. Here we study, for the first time, the impact of varying degrees of exploration rates - the likelihood of spontaneously adopting another strategy, akin to a mutation probability in evolutionary dynamics - in the emergence of cooperation under IR. We show that high exploration rates may either improve or harm cooperation, depending on the underlying social norm at work. Regarding some of the most popular social norms studied to date, we find that cooperation under Simple-standing and Image-score is enhanced by high exploration rates, whereas the opposite occurs for Stern-judging and Shunning.

Direct and indirect punishment among strangers in the field.

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Balafoutas, Loukas; Nikiforakis, Nikos; Rockenbach, Bettina

2014-11-11

Many interactions in modern human societies are among strangers. Explaining cooperation in such interactions is challenging. The two most prominent explanations critically depend on individuals' willingness to punish defectors: In models of direct punishment, individuals punish antisocial behavior at a personal cost, whereas in models of indirect reciprocity, they punish indirectly by withholding rewards. We investigate these competing explanations in a field experiment with real-life interactions among strangers. We find clear evidence of both direct and indirect punishment. Direct punishment is not rewarded by strangers and, in line with models of indirect reciprocity, is crowded out by indirect punishment opportunities. The existence of direct and indirect punishment in daily life indicates the importance of both means for understanding the evolution of cooperation.

Gossip as an alternative for direct observation in games of indirect reciprocity.

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Sommerfeld, Ralf D; Krambeck, Hans-Jürgen; Semmann, Dirk; Milinski, Manfred

2007-10-30

Communication about social topics is abundant in human societies, and many functions have been attributed to such gossiping. One of these proposed functions is the management of reputations. Reputation by itself has been shown to have a strong influence on cooperation dynamics in games of indirect reciprocity, and this notion helps to explain the observed high level of cooperation in humans. Here we designed a game to test a widespread assumption that gossip functions as a vector for the transmission of social information. This empirical study (with 14 groups of nine students each) focuses on the composition of gossip, information transfer by gossip, and the behavior based on gossip information. We show that gossip has a strong influence on the resulting behavior even when participants have access to the original information (i.e., direct observation) as well as gossip about the same information. Thus, it is evident that gossip has a strong manipulative potential. Furthermore, gossip about cooperative individuals is more positive than gossip about uncooperative individuals, gossip comments transmit social information successfully, and cooperation levels are higher when people encounter positive compared with negative gossip.

Participation costs can suppress the evolution of upstream reciprocity.

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Peña, Jorge; Pestelacci, Enea; Berchtold, André; Tomassini, Marco

2011-03-21

Indirect reciprocity, one of the many mechanisms proposed to explain the evolution of cooperation, is the idea that altruistic actions can be rewarded by third parties. Upstream or generalized reciprocity is one type of indirect reciprocity in which individuals help someone if they have been helped by somebody else in the past. Although empirically found to be at work in humans, the evolution of upstream reciprocity is difficult to explain from a theoretical point of view. A recent model of upstream reciprocity, first proposed by Nowak and Roch (2007) and further analyzed by Iwagami and Masuda (2010), shows that while upstream reciprocity alone does not lead to the evolution of cooperation, it can act in tandem with mechanisms such as network reciprocity and increase the total level of cooperativity in the population. We argue, however, that Nowak and Roch's model systematically leads to non-uniform interaction rates, where more cooperative individuals take part in more games than less cooperative ones. As a result, the critical benefit-to-cost ratios derived under this model in previous studies are not invariant with respect to the addition of participation costs. We show that accounting for these costs can hinder and even suppress the evolution of upstream reciprocity, both for populations with non-random encounters and graph-structured populations. Copyright © 2011 Elsevier Ltd. All rights reserved.

Indirect transformation in reciprocal space: desmearing of small-angle scattering data from partially ordered systems

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Glatter, O.; Gruber, K.

1993-01-01

Indirect Fourier transformation is a widely used technique for the desmearing of instrumental broadening effects, for data smoothing and for Fourier transformation of small-angle scattering data. This technique, however, can only be applied to scattering curves with a band-limited Fourier transform, i.e. separated and noninteracting scattering centers. It can therefore not be used for scattering data from partially ordered systems. In this paper, a modified technique for partially ordered systems working in reciprocal space is presented. A peak-recognition technique allows its application to scattering functions with narrow peaks, such as the scattering functions of layered systems like lamellar stacks or strongly interacting particles. Arbitrary geometry effects and wavelength effects can be corrected. Examples of simulations show the merits and limits of this new method. One example shows its applicability to real data. (orig.)

Hidden patterns of reciprocity.

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Syi

2014-03-21

Reciprocity can help the evolution of cooperation. To model both types of reciprocity, we need the concept of strategy. In the case of direct reciprocity there are four second-order action rules (Simple Tit-for-tat, Contrite Tit-for-tat, Pavlov, and Grim Trigger), which are able to promote cooperation. In the case of indirect reciprocity the key component of cooperation is the assessment rule. There are, again, four elementary second-order assessment rules (Image Scoring, Simple Standing, Stern Judging, and Shunning). The eight concepts can be formalized in an ontologically thin way we need only an action predicate and a value function, two agent concepts, and the constant of goodness. The formalism helps us to discover that the action and assessment rules can be paired, and that they show the same patterns. The logic of these patterns can be interpreted with the concept of punishment that has an inherent paradoxical nature. Copyright © 2013 Elsevier Ltd. All rights reserved.

A Theoretical Approach to Norm Ecosystems: Two Adaptive Architectures of Indirect Reciprocity Show Different Paths to the Evolution of Cooperation

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Satoshi Uchida

2018-02-01

Full Text Available Indirect reciprocity is one of the basic mechanisms to sustain mutual cooperation, by which beneficial acts are returned, not by the recipient, but by third parties. This mechanism relies on the ability of individuals to know the past actions of others, and to assess those actions. There are many different systems of assessing others, which can be interpreted as rudimentary social norms (i.e., views on what is “good” or “bad”. In this paper, impacts of different adaptive architectures, i.e., ways for individuals to adapt to environments, on indirect reciprocity are investigated. We examine two representative architectures: one based on replicator dynamics and the other on genetic algorithm. Different from the replicator dynamics, the genetic algorithm requires describing the mixture of all possible norms in the norm space under consideration. Therefore, we also propose an analytic method to study norm ecosystems in which all possible second order social norms potentially exist and compete. The analysis reveals that the different adaptive architectures show different paths to the evolution of cooperation. Especially we find that so called Stern-Judging, one of the best studied norms in the literature, exhibits distinct behaviors in both architectures. On one hand, in the replicator dynamics, Stern-Judging remains alive and gets a majority steadily when the population reaches a cooperative state. On the other hand, in the genetic algorithm, it gets a majority only temporarily and becomes extinct in the end.

A Theoretical Approach to Norm Ecosystems: Two Adaptive Architectures of Indirect Reciprocity Show Different Paths to the Evolution of Cooperation

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Uchida, Satoshi; Yamamoto, Hitoshi; Okada, Isamu; Sasaki, Tatsuya

2018-02-01

Indirect reciprocity is one of the basic mechanisms to sustain mutual cooperation, by which beneficial acts are returned, not by the recipient, but by third parties. This mechanism relies on the ability of individuals to know the past actions of others, and to assess those actions. There are many different systems of assessing others, which can be interpreted as rudimentary social norms (i.e., views on what is “good” or “bad”). In this paper, impacts of different adaptive architectures, i.e., ways for individuals to adapt to environments, on indirect reciprocity are investigated. We examine two representative architectures: one based on replicator dynamics and the other on genetic algorithm. Different from the replicator dynamics, the genetic algorithm requires describing the mixture of all possible norms in the norm space under consideration. Therefore, we also propose an analytic method to study norm ecosystems in which all possible second order social norms potentially exist and compete. The analysis reveals that the different adaptive architectures show different paths to the evolution of cooperation. Especially we find that so called Stern-Judging, one of the best studied norms in the literature, exhibits distinct behaviors in both architectures. On one hand, in the replicator dynamics, Stern-Judging remains alive and gets a majority steadily when the population reaches a cooperative state. On the other hand, in the genetic algorithm, it gets a majority only temporarily and becomes extinct in the end.

The Explanatory Power of Reciprocal Behavior for the Inter-Organizational Exchange Context

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Martina Pieperhoff

2018-06-01

Full Text Available In order to create sustainable competitive advantages, organizations are embedded in dyadic exchange relationships, which depend on the coordination of the behavior of the actors involved. Often, coordinated behavior is explained by trust. Since trust develops in a process of reciprocal responses to presumed trustworthy behavior, it is a reciprocity-based concept. While inter-organizational exchange relationships can appear in different stages (forming, establishing, broken, different reciprocity types (direct, indirect, negative can be distinguished. The study links reciprocal behavior to different stages of inter-organizational exchange relationships in order to investigate reciprocity as a possible coordination mechanism of behavior and thus explore the basis of coordination of trust-based behavior. Qualitative Comparative Analysis as a set-theoretic approach is applied to analyze the empirical data consisting of 78 qualitative semi-structured interviews with managers of small-, medium- and large-sized companies. The results show that different reciprocity types become effective in different stages of an inter-organizational exchange relationship: For forming inter-organizational exchange relationships indirect reciprocal behavior, besides direct reciprocity, becomes effective while in establishing inter-organizational exchange relationships, direct reciprocal behavior is evident. Negative reciprocal behavior leads to a break up of relationships. Using these results, on the one hand, the concept of trust can be sharpened by deepening the understanding of the trust-building mechanisms and on the other hand, reciprocity can be seen as coordination mechanism in exchange relationships of different stages. In doing so, with this knowledge, relationships can be coordinated towards a long-term orientation in order to create sustainable advantages.

Stuttering in Preschool Children: Direct versus Indirect Treatment

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Nippold, Marilyn A.

2018-01-01

Purpose: The purpose of this article is to discuss the controversial topic of stuttering in preschool children and how to evaluate the options for treatment, emphasizing the role of external research evidence. Method: A hypothetical but realistic case study of a 3-year-old boy who stutters is described. Two contrasting approaches to treatment are…

Indirect Reciprocity, Resource Sharing, and Environmental Risk: Evidence from Field Experiments in Siberia

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Howe, E. Lance; Murphy, James J.; Gerkey, Drew; West, Colin Thor

2016-01-01

Integrating information from existing research, qualitative ethnographic interviews, and participant observation, we designed a field experiment that introduces idiosyncratic environmental risk and a voluntary sharing decision into a standard public goods game. Conducted with subsistence resource users in rural villages on the Kamchatka Peninsula in Northeast Siberia, we find evidence consistent with a model of indirect reciprocity and local social norms of helping the needy. When participants are allowed to develop reputations in the experiments, as is the case in most small-scale societies, we find that sharing is increasingly directed toward individuals experiencing hardship, good reputations increase aid, and the pooling of resources through voluntary sharing becomes more effective. We also find high levels of voluntary sharing without a strong commitment device; however, this form of cooperation does not increase contributions to the public good. Our results are consistent with previous experiments and theoretical models, suggesting strategic risks tied to rewards, punishments, and reputations are important. However, unlike studies that focus solely on strategic risks, we find the effects of rewards, punishments, and reputations are altered by the presence of environmental factors. Unexpected changes in resource abundance increase interdependence and may alter the costs and benefits of cooperation, relative to defection. We suggest environmental factors that increase interdependence are critically important to consider when developing and testing theories of cooperation PMID:27442434

Direct reciprocity in structured populations.

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van Veelen, Matthijs; García, Julián; Rand, David G; Nowak, Martin A

2012-06-19

Reciprocity and repeated games have been at the center of attention when studying the evolution of human cooperation. Direct reciprocity is considered to be a powerful mechanism for the evolution of cooperation, and it is generally assumed that it can lead to high levels of cooperation. Here we explore an open-ended, infinite strategy space, where every strategy that can be encoded by a finite state automaton is a possible mutant. Surprisingly, we find that direct reciprocity alone does not lead to high levels of cooperation. Instead we observe perpetual oscillations between cooperation and defection, with defection being substantially more frequent than cooperation. The reason for this is that "indirect invasions" remove equilibrium strategies: every strategy has neutral mutants, which in turn can be invaded by other strategies. However, reciprocity is not the only way to promote cooperation. Another mechanism for the evolution of cooperation, which has received as much attention, is assortment because of population structure. Here we develop a theory that allows us to study the synergistic interaction between direct reciprocity and assortment. This framework is particularly well suited for understanding human interactions, which are typically repeated and occur in relatively fluid but not unstructured populations. We show that if repeated games are combined with only a small amount of assortment, then natural selection favors the behavior typically observed among humans: high levels of cooperation implemented using conditional strategies.

Clustering in large networks does not promote upstream reciprocity.

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Naoki Masuda

Full Text Available Upstream reciprocity (also called generalized reciprocity is a putative mechanism for cooperation in social dilemma situations with which players help others when they are helped by somebody else. It is a type of indirect reciprocity. Although upstream reciprocity is often observed in experiments, most theories suggest that it is operative only when players form short cycles such as triangles, implying a small population size, or when it is combined with other mechanisms that promote cooperation on their own. An expectation is that real social networks, which are known to be full of triangles and other short cycles, may accommodate upstream reciprocity. In this study, I extend the upstream reciprocity game proposed for a directed cycle by Boyd and Richerson to the case of general networks. The model is not evolutionary and concerns the conditions under which the unanimity of cooperative players is a Nash equilibrium. I show that an abundance of triangles or other short cycles in a network does little to promote upstream reciprocity. Cooperation is less likely for a larger population size even if triangles are abundant in the network. In addition, in contrast to the results for evolutionary social dilemma games on networks, scale-free networks lead to less cooperation than networks with a homogeneous degree distribution.

Clustering in large networks does not promote upstream reciprocity.

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Masuda, Naoki

2011-01-01

Upstream reciprocity (also called generalized reciprocity) is a putative mechanism for cooperation in social dilemma situations with which players help others when they are helped by somebody else. It is a type of indirect reciprocity. Although upstream reciprocity is often observed in experiments, most theories suggest that it is operative only when players form short cycles such as triangles, implying a small population size, or when it is combined with other mechanisms that promote cooperation on their own. An expectation is that real social networks, which are known to be full of triangles and other short cycles, may accommodate upstream reciprocity. In this study, I extend the upstream reciprocity game proposed for a directed cycle by Boyd and Richerson to the case of general networks. The model is not evolutionary and concerns the conditions under which the unanimity of cooperative players is a Nash equilibrium. I show that an abundance of triangles or other short cycles in a network does little to promote upstream reciprocity. Cooperation is less likely for a larger population size even if triangles are abundant in the network. In addition, in contrast to the results for evolutionary social dilemma games on networks, scale-free networks lead to less cooperation than networks with a homogeneous degree distribution.

Reciprocity on the hardwood: passing patterns among professional basketball players.

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Robb Willer

Full Text Available Past theory and research view reciprocal resource sharing as a fundamental building block of human societies. Most studies of reciprocity dynamics have focused on trading among individuals in laboratory settings. But if motivations to engage in these patterns of resource sharing are powerful, then we should observe forms of reciprocity even in highly structured group environments in which reciprocity does not clearly serve individual or group interests. To this end, we investigated whether patterns of reciprocity might emerge among teammates in professional basketball games. Using data from logs of National Basketball Association (NBA games of the 2008-9 season, we estimated a series of conditional logistic regression models to test the impact of different factors on the probability that a given player would assist another player in scoring a basket. Our analysis found evidence for a direct reciprocity effect in which players who had "received" assists in the past tended to subsequently reciprocate their benefactors. Further, this tendency was time-dependent, with the probability of repayment highest soon after receiving an assist and declining as game time passed. We found no evidence for generalized reciprocity - a tendency to "pay forward" assists - and only very limited evidence for indirect reciprocity - a tendency to reward players who had sent others many assists. These findings highlight the power of reciprocity to shape human behavior, even in a setting characterized by extensive planning, division of labor, quick decision-making, and a focus on inter-group competition.

Reciprocity on the hardwood: passing patterns among professional basketball players.

Science.gov (United States)

Willer, Robb; Sharkey, Amanda; Frey, Seth

2012-01-01

Past theory and research view reciprocal resource sharing as a fundamental building block of human societies. Most studies of reciprocity dynamics have focused on trading among individuals in laboratory settings. But if motivations to engage in these patterns of resource sharing are powerful, then we should observe forms of reciprocity even in highly structured group environments in which reciprocity does not clearly serve individual or group interests. To this end, we investigated whether patterns of reciprocity might emerge among teammates in professional basketball games. Using data from logs of National Basketball Association (NBA) games of the 2008-9 season, we estimated a series of conditional logistic regression models to test the impact of different factors on the probability that a given player would assist another player in scoring a basket. Our analysis found evidence for a direct reciprocity effect in which players who had "received" assists in the past tended to subsequently reciprocate their benefactors. Further, this tendency was time-dependent, with the probability of repayment highest soon after receiving an assist and declining as game time passed. We found no evidence for generalized reciprocity - a tendency to "pay forward" assists - and only very limited evidence for indirect reciprocity - a tendency to reward players who had sent others many assists. These findings highlight the power of reciprocity to shape human behavior, even in a setting characterized by extensive planning, division of labor, quick decision-making, and a focus on inter-group competition.

Experimental Study of Middle-Term Training in Social Cognition in Preschoolers

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Houssa, Marine; Nader-Grosbois, Nathalie

2016-01-01

In an experimental design, we examined the effects of middle-term training in social information processing (SIP) and in Theory of Mind (ToM) on preschoolers' social cognition and social adjustment. 48 preschoolers took part in a pre-test and post-test session involving cognitive, socio-cognitive and social adjustment (direct and indirect)…

Reciprocity, Elder Satisfaction, and Caregiver Stress and Burden: The Exchange of Aid in the Family Caregiving Relationship.

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Dwyer, Jeffrey W.; And Others

1994-01-01

Examined how older mother's reciprocation of assistance provided by caregiving daughter simultaneously influences satisfaction of mother and stress/burden of caregiver in 135 mother-daughter dyads. Results indicated that reciprocity did not directly or indirectly affect mother's satisfaction but did significantly reduce stress/burden of daughters.…

Function, Type, and Distribution of Teacher Questions in Dual-Language Preschool Read Alouds

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Gort, Mileidis; Pontier, Ryan W.; Sembiante, Sabrina F.

2012-01-01

This exploratory study investigated the nature and distribution of dual-language preschool teachers' questions across parallel Spanish- and English-medium read-aloud activities. The notions of comprehensible input (Krashen, 1985) and language output (Swain, 1985), along with a reciprocal interaction model of teaching (Cummins, 2000), guided our…

Quality of Play, Social Acceptance and Reciprocal Friendship in Preschool Children

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Coelho, Leandra; Torres, Nuno; Fernandes, Carla; Santos, António J.

2017-01-01

Playing with peers is one of the most important contexts for the acquisition of social competencies in early childhood. This study examined the relation between children's play behavior, social acceptance in the peer group, and number of reciprocal friendships. One hundred and twenty eight children, aged between three and five years, participated…

Chinese Parents' Expectations and Child Preacademic Skills: The Indirect Role of Parenting and Social Competence

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Ren, Lixin; Edwards, Carolyn Pope

2017-01-01

Research Findings: This study examined how parenting styles and child social-emotional functioning may help explain the indirect relations between Chinese parents' expectations for their preschool-age children's social-emotional development and their children's preacademic skills. A total of 154 parents with preschool-age children were recruited…

The reciprocal and indirect relationships between passive Facebook use, comparison on Facebook, and adolescents’ body dissatisfaction

OpenAIRE

Rousseau, Ann; Eggermont, Steven; Frison, Eline

2017-01-01

Facebook has been found to provide a fertile ground for social comparison. Emerging evidence indicates that social comparison may mediate the relationship between Facebook use and young people’s body dissatisfaction. Yet, little work has been done on how these relationships evolve over time in adolescence and no study has examined the reciprocal relationships between passive Facebook use, social comparison, and adolescents’ body dissatisfaction. To examine these reciprocal relationships, t...

THE ENVIRONMENT AS A CRUCIAL LEARNING FACTOR AT PRE-SCHOOL

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Snježana Močinić

2016-01-01

Full Text Available In this essay, the author hypothesizes that physical environment is an essential factor for developing an educational project. The environment is considered a sort of "third educator", playing a decisive role in determining the quality of learning. Classrooms, laboratory, the corridor, the structure of the building itself and the context in which the building is placed; the colours of the walls, the quality of natural and artificial light in the building, the furniture and materials for learning are variables which determine the environment where a child lives, learns, experiences, begins relationships with other people. The educator is very important in the process of a child's development. By means of direct and indirect action, he/she can create an attractive space in the building, more accessible for the processes of functional learning. The empirical research, described in the present survey, underlines the importance of pre-schools as an important place for meeting, interaction, listening and reciprocity leading toward an improvement in the relationship between the child and the school environment. In particular, this empirical research will show the diversity of the places and materials teachers made available to children.

An experimental study of strong reciprocity in bacteria.

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Inglis, R Fredrik; West, Stuart; Buckling, Angus

2014-02-01

Strong reciprocity, whereby cooperators punish non-cooperators, may help to explain the evolutionary success of cooperative behaviours. However, theory suggests that selection for strong reciprocity can depend upon tight genetic linkage between cooperation and punishment, to avoid the strategy being outcompeted by non-punishing cooperators. We tested this hypothesis using experimental populations of the bacterium Pseudomonas aeruginosa, which cooperate by producing iron-scavenging siderophores and, in this context, punish non-cooperators with toxins. Consistent with theory, we show that cooperative punishers can indeed invade cheats, but only when the traits are tightly linked. These results emphasize that punishment is only likely to be favoured when the punishment itself leads to a direct or indirect fitness benefit to the actor.

Planning and Evaluating Educational Work in Slovene Preschools

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Marcela Batistič Zorec

2012-01-01

Full Text Available The present article examines the changes in Slovene preschools subsequent to Slovenia’s independence in 1991. In the socialist period, the national education programme for preschools was highly structured, goaland content-oriented and subject to schoolization. The Curriculum for Preschools (1999 brought conceptual changes towards education “based on the child” and the process approach, as well as giving more autonomy to preschool teachers and their assistants. In the empirical study, we examine changes in planning and evaluating educational work compared to the past. The results show that the majority of professional workers have reduced the high level of structure and rigidity in planning, and that there is better cooperation between preschool teachers and teachers’ assistants. Unlike in the past, most professional workers regularly evaluate their educational work. As the data was gathered in two phases, before and after the training of professional workers in the Reggio Emilia concept, we also search for the (probably indirect influencesof this training. We conclude that after the training the participation of children in planning and evaluating educational work is higher.

Peer Rejection and Internalizing Behavior: The Mediating Role of Peer Victimization in Preschool.

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Metin Aslan, Özge

2018-05-23

The author examined the relationship among peer rejection, peer victimization, and internalizing behaviors. The author hypothesized that physical and relational victimization would have a different indirect effect on the relationship between peer rejection and internalizing behaviors. Participants were 94 preschool children (37 girls; average age 49.97 months) from two university preschools located in the northern part of the United States. The results indicated that internalizing behaviors predicted the mediating variables only regarding relational victimization. Relational victimization indirectly affected the association between peer rejection and internalizing behaviors. The study provides evidence of the mediating effect of victimization behaviors on the relationship among peer rejection, victimization, and internalizing behaviors.

CREATIVITY OF PRESCHOOL AND ELEMENTARY SCHOOL TEACHERS AND THEIR STUDENTS.

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Sali, Güneş; Akyol, Aysel Köksal

2015-12-01

Although creativity provides a considerable number of advantages, many teachers have direct and indirect prejudices against creative students since they may display distracting and disruptive behaviors toward teachers and classmates. To determine how teachers' creativity affects their students' creative development, 90 preschool and elementary school teachers and 90 pupils were assessed for creative thinking. The children's sex was not correlated with creativity scores. There were small, significant relationships between various measures of preschool teachers' and students' creativity.

The logic of indirect speech

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Pinker, Steven; Nowak, Martin A.; Lee, James J.

2008-01-01

When people speak, they often insinuate their intent indirectly rather than stating it as a bald proposition. Examples include sexual come-ons, veiled threats, polite requests, and concealed bribes. We propose a three-part theory of indirect speech, based on the idea that human communication involves a mixture of cooperation and conflict. First, indirect requests allow for plausible deniability, in which a cooperative listener can accept the request, but an uncooperative one cannot react adversarially to it. This intuition is supported by a game-theoretic model that predicts the costs and benefits to a speaker of direct and indirect requests. Second, language has two functions: to convey information and to negotiate the type of relationship holding between speaker and hearer (in particular, dominance, communality, or reciprocity). The emotional costs of a mismatch in the assumed relationship type can create a need for plausible deniability and, thereby, select for indirectness even when there are no tangible costs. Third, people perceive language as a digital medium, which allows a sentence to generate common knowledge, to propagate a message with high fidelity, and to serve as a reference point in coordination games. This feature makes an indirect request qualitatively different from a direct one even when the speaker and listener can infer each other's intentions with high confidence. PMID:18199841

Interpreting values in the daily practices of Nordic preschools

DEFF Research Database (Denmark)

Broström, Stig; Anna-Maija, Puriola; Johannesson, Eva Marianne

2016-01-01

Abstract This study explored how practitioners interpreted educational practices from the perspective of values in Nordic preschools. Drawing data from group interviews in five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden), practitioners reflected on an observational episode about...... children dressing for outdoor play in a Swedish preschool. The research material consisted of extracts from group interviews in ten preschools (two from each Nordic country). The research questions included: How do values emerge in practitioners’ interpretations? What is the interpretive process like...... and the co-construction of interpretations in the group dialogues. The practitioners employed indirect means more often than direct means to express their values. The group interviews contained themes that were connected to caring, disciplinary, competence and democratic values. The study provided evidence...

Cyclic Fatigue Resistance of Reciproc Blue, Reciproc, and WaveOne Gold Reciprocating Instruments.

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Keskin, Cangül; Inan, Uğur; Demiral, Murat; Keleş, Ali

2017-08-01

The aim of the present study was to compare the cyclic fatigue resistance of Reciproc Blue R25 (VDW, Munich, Germany) with Reciproc R25 (VDW) and WaveOne Gold Primary (Denstply Maillefer, Ballaigues, Switzerland). Fifteen Reciproc Blue R25, 15 Reciproc R25, and 15 WaveOne Gold Primary instruments were collected and tested in a dynamic cyclic fatigue test device, which has an artificial canal with a 60° angle of curvature and a 5-mm radius of curvature. All instruments were operated until fracture occurred, and time to fracture (TF) and the lengths of the fractured fragments were recorded. The mean and standard deviations of TF and fragment length were calculated for each reciprocating system. TF data were subjected to Kruskal-Wallis 1-way analysis of variance and the Dunn test, whereas fractured fragment length data were subjected to 1-way analysis of variance (P  .05). Reciproc Blue R25 instruments had significantly higher cyclic fatigue resistance than WaveOne Gold and Reciproc R25 instruments. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Direct reciprocity in spatial populations enhances R-reciprocity as well as ST-reciprocity.

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Miyaji, Kohei; Tanimoto, Jun; Wang, Zhen; Hagishima, Aya; Ikegaya, Naoki

2013-01-01

As is well-known, spatial reciprocity plays an important role in facilitating the emergence of cooperative traits, and the effect of direct reciprocity is also obvious for explaining the cooperation dynamics. However, how the combination of these two scenarios influences cooperation is still unclear. In the present work, we study the evolution of cooperation in 2 × 2 games via considering both spatial structured populations and direct reciprocity driven by the strategy with 1-memory length. Our results show that cooperation can be significantly facilitated on the whole parameter plane. For prisoner's dilemma game, cooperation dominates the system even at strong dilemma, where maximal social payoff is still realized. In this sense, R-reciprocity forms and it is robust to the extremely strong dilemma. Interestingly, when turning to chicken game, we find that ST-reciprocity is also guaranteed, through which social average payoff and cooperation is greatly enhanced. This reciprocity mechanism is supported by mean-field analysis and different interaction topologies. Thus, our study indicates that direct reciprocity in structured populations can be regarded as a more powerful factor for the sustainability of cooperation.

Mother and preschool teacher as assessors of the child's language competence

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Urška Fekonja Peklaj

2008-04-01

Full Text Available Many researchers include child's parents as assessors of his/her language development as the results of many studies suggest their assessments to be valid and reliable measures of child's language competence. In the longitudinal study, presented in this paper, we examined whether child's mother and his/her preschool teacher can provide a valid estimation of child's language development. The sample included 80 Slovenian children from different preschool institutions, aged 3;1 years at first and 4;1 years at second assessment. Children's language competence was assessed individually, directly by the testators using Language Development Scale and Storytelling Test and indirectly by mothers and preschool teachers using the Child's Language Competence Questionnaire for Parents and Preschool Teachers. The achieved results showed that the estimates given by mothers and preschool teachers represent valid measures of child's language competence but not stable in time. The estimations given by mothers and preschool teachers explain a small share in variability of children's achievements on the Language Development Scale and Storytelling Test.

How the indirect reciprocity with co-evolving norm and strategy for 2 × 2 prisoner's dilemma game works for emerging cooperation

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Tanimoto, Jun; Sagara, Hirokji

2015-11-01

We built a new indirect reciprocity model based on binary image scores, where an agent's strategy and norm co-evolve. The norm, meaning what behavior is evaluated as "good" or "bad," stipulates how image scores of two agents playing a game is altered, which has been presumed to be a fixed value in most previous studies. Also, unlike former studies, our model allows an agent to play with an agent who has a different norm. This point of relaxing the freedom of the model pulls down cooperation level vis-à-vis the case where an agent always plays with another one having same norm. However, it is observed that a rather larger dilemma shows robust cooperation establishing compared with a smaller dilemma, since a norm that punishes a so-called second-order free-rider is prompted. To encourage the evolution of norms to be able to punish second-order free-riders, a society needs a small number of defectors. This is elucidated by the fact that cases with action error are more cooperative than those without action error.

Cutting efficiency of Reciproc and waveOne reciprocating instruments.

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Plotino, Gianluca; Giansiracusa Rubini, Alessio; Grande, Nicola M; Testarelli, Luca; Gambarini, Gianluca

2014-08-01

The aim of the present study was to evaluate the cutting efficiency of 2 new reciprocating instruments, Reciproc and WaveOne. Twenty-four new Reciproc R25 and 24 new WaveOne Primary files were activated by using a torque-controlled motor (Silver Reciproc) and divided into 4 groups (n = 12): group 1, Reciproc activated by Reciproc ALL program; group 2, Reciproc activated by WaveOne ALL program; group 3, WaveOne activated by Reciproc ALL program; and group 4, WaveOne activated by WaveOne ALL program. The device used for the cutting test consisted of a main frame to which a mobile plastic support for the handpiece is connected and a stainless steel block containing a Plexiglas block (inPlexiglass, Rome, Italy) against which the cutting efficiency of the instruments was tested. The length of the block cut in 1 minute was measured in a computerized program with a precision of 0.1 mm. Means and standard deviations of each group were calculated, and data were statistically analyzed with 1-way analysis of variance and Bonferroni test (P cutting efficiency than WaveOne Primary for both the movements used (P cutting efficiency than WaveOne instruments used with their proper reciprocating motion (P .05). Reciproc instruments demonstrated statistically higher cutting efficiency than WaveOne instruments. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Factors Influencing Implementation of a Preschool-Based Physical Activity Intervention

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Lau, Erica Y.; Saunders, Ruth P.; Beets, Michael W.; Cai, Bo; Pate, Russell R.

2017-01-01

Examining factors that influence implementation of key program components that underlie an intervention's success provides important information to inform the development of effective dissemination strategies. We examined direct and indirect effects of preschool capacity, quality of prevention support system and teacher characteristics on…

Reciprocity in optics

International Nuclear Information System (INIS)

Potton, R J

2004-01-01

The application of reciprocity principles in optics has a long history that goes back to Stokes, Lorentz, Helmholtz and others. Moreover, optical applications need to be seen in the context of applications of reciprocity in particle scattering, acoustics, seismology and the solution of inverse problems, generally. In some of these other fields vector wave propagation is, as it is in optics, of the essence. For this reason the simplified approach to light wave polarization developed by, and named for, Jones is explored initially to see how and to what extent it encompasses reciprocity. The characteristic matrix of a uniform dielectric layer, used in the analysis of interference filters and mirrors, is reciprocal except when the layer is magneto-optical. The way in which the reciprocal nature of a characteristic matrix can be recognized is discussed next. After this, work on the influence of more realistic attributes of a dielectric stack on reciprocity is reviewed. Some of the numerous technological applications of magneto-optic non-reciprocal media are identified and the potential of a new class of non-reciprocal components is briefly introduced. Finally, the extension of the classical reciprocity concept to systems containing components that have nonlinear optical response is briefly mentioned

Parental Support Exceeds Parenting Style for Promoting Active Play in Preschool Children

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Schary, David P.; Cardinal, Bradley J.; Loprinzi, Paul D.

2012-01-01

Emerging evidence suggests that parenting style may directly or indirectly influence school-aged children's activity behaviour. Given that relatively fewer studies have been conducted among preschool-aged children, this study's primary purpose was to examine the direct relationships between parental support and parenting style on preschool…

Reciprocating pellet press

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Jones, Charles W.

1981-04-07

A machine for pressing loose powder into pellets using a series of reciprocating motions has an interchangeable punch and die as its only accurately machines parts. The machine reciprocates horizontally between powder receiving and pressing positions. It reciprocates vertically to press, strip and release a pellet.

Reciprocity of weighted networks.

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Squartini, Tiziano; Picciolo, Francesco; Ruzzenenti, Franco; Garlaschelli, Diego

2013-01-01

In directed networks, reciprocal links have dramatic effects on dynamical processes, network growth, and higher-order structures such as motifs and communities. While the reciprocity of binary networks has been extensively studied, that of weighted networks is still poorly understood, implying an ever-increasing gap between the availability of weighted network data and our understanding of their dyadic properties. Here we introduce a general approach to the reciprocity of weighted networks, and define quantities and null models that consistently capture empirical reciprocity patterns at different structural levels. We show that, counter-intuitively, previous reciprocity measures based on the similarity of mutual weights are uninformative. By contrast, our measures allow to consistently classify different weighted networks according to their reciprocity, track the evolution of a network's reciprocity over time, identify patterns at the level of dyads and vertices, and distinguish the effects of flux (im)balances or other (a)symmetries from a true tendency towards (anti-)reciprocation.

The personal norm of reciprocity

NARCIS (Netherlands)

Perugini, M.; Gallucci, M.; Presaghi, F.; Ercolani, A.P.

2002-01-01

Reciprocity is here considered as an internalized social norm, and a questionnaire to measure individual differences in the internalized norm of reciprocity is presented. The questionnaire, Personal Norm of Reciprocity (PNR), measures three aspects of reciprocity: positive reciprocity, negative

Preschool Teachers' Professional Training, Observational Feedback, Child-Centered Beliefs and Motivation: Direct and Indirect Associations with Social and Emotional Responsiveness

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Lang, Sarah N.; Mouzourou, Chryso; Jeon, Lieny; Buettner, Cynthia K.; Hur, Eunhye

2017-01-01

Background: Young children's social and emotional competence is a key predictor of their current and future academic and social success. Although preschool teachers are critical socializing agent of children's social and emotional development, we know little about factors associated with preschool teachers' social and emotional responsiveness.…

Reciprocity, culture and human cooperation: previous insights and a new cross-cultural experiment.

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Gächter, Simon; Herrmann, Benedikt

2009-03-27

Understanding the proximate and ultimate sources of human cooperation is a fundamental issue in all behavioural sciences. In this paper, we review the experimental evidence on how people solve cooperation problems. Existing studies show without doubt that direct and indirect reciprocity are important determinants of successful cooperation. We also discuss the insights from a large literature on the role of peer punishment in sustaining cooperation. The experiments demonstrate that many people are 'strong reciprocators' who are willing to cooperate and punish others even if there are no gains from future cooperation or any other reputational gains. We document this in new one-shot experiments, which we conducted in four cities in Russia and Switzerland. Our cross-cultural approach allows us furthermore to investigate how the cultural background influences strong reciprocity. Our results show that culture has a strong influence on positive and in especially strong negative reciprocity. In particular, we find large cross-cultural differences in 'antisocial punishment' of pro-social cooperators. Further cross-cultural research and experiments involving different socio-demographic groups document that the antisocial punishment is much more widespread than previously assumed. Understanding antisocial punishment is an important task for future research because antisocial punishment is a strong inhibitor of cooperation.

Understanding the complex determinants of height and adiposity in disadvantaged daycare preschoolers in Salvador, NE Brazil through structural equation modelling.

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Lander, Rebecca L; Williams, Sheila M; Costa-Ribeiro, Hugo; Mattos, Angela P; Barreto, Danile L; Houghton, Lisa A; Bailey, Karl B; Lander, Alastair G; Gibson, Rosalind S

2015-10-23

Earlier we reported on growth and adiposity in a cross-sectional study of disadvantaged Brazilian preschoolers. Here we extend the work on these children, using structural equation modelling (SEM) to gather information on the complex relationships between the variables influencing height and adiposity. We hope this information will help improve the design and effectiveness of future interventions for preschoolers. In 376 preschoolers aged 3-6 years attending seven philanthropic daycares in Salvador, we used SEM to examine direct and indirect relationships among biological (sex, ethnicity, birth order, maternal height and weight), socio-economic, micronutrient (haemoglobin, serum selenium and zinc), and environmental (helminths, de-worming) variables on height and adiposity, as reflected by Z-scores for height-for-age (HAZ) and body mass index (BMIZ). Of the children, 11 % had HAZ  1. Of their mothers, 8 % had short stature, and 50 % were overweight or obese. Based on standardized regression coefficients, significant direct effects (p growth, helminth infection was a modifiable risk factor directly and indirectly affecting HAZ and BMIZ, respectively. Hence the WHO de-worming recommendation should include preschoolers living in at-risk environments as well as school-aged children.

A systematic review and meta-analysis of comprehensive interventions for pre-school children with autism spectrum disorder (ASD.

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Yoshiyuki Tachibana

Full Text Available There has an increasing number of published trials on psychosocial intervention programmes for pre-school children with autism spectrum disorder (ASD. To achieve better quality of unbiased evidence for the effectiveness of ASD interventions, it is necessary to conduct a comprehensive review that covers studies with adequate quality standards, such as randomised controlled trials (RCTs, and different types of intervention In this study, we categorize interventions for ASD as behavioural, social-communication focused, and multimodal developmental based on Howlin's classification of early interventions for children with ASD. The aim of this study was to compare these three models and investigate the strengths and weaknesses of each type of intervention and to identify the approaches that contribute to a successful outcome for children with autism.We performed a systematic review and meta-analysis. We included RCTs targeting children with ASD 6 years old or younger. A random effects model was used to present the effect estimate for the outcomes. This study also performed combined meta-analyses of all the three models to investigate the overall effectiveness of the intervention programmes.32 randomized controlled studies were found to be eligible for inclusion. The synthesized data included 594 children from 14 RCTs. There was no statistically significant difference in the effects on autism general symptoms between the social-communication-focused model and the multimodal developmental model (p = 0.83. The results suggest that there is evidence of an effect on 'reciprocity of social interaction towards others' (standard mean difference [95% confidential interval] = 0.53[0.29,0.78], p<0.01 and 'parental synchrony' (SMD = 0.99[0.70,1.29], p<0.01.The small number of studies included in the present study limited the ability to make inferences when comparing the three models and investigating the strengths and weaknesses of each type of intervention with

Unpacking socio-economic risks for reading and academic self-concept in primary school: Differential effects and the role of the preschool home learning environment.

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Crampton, Alexandria; Hall, James

2017-09-01

Uncertainty remains concerning how children's reading and academic self-concept are related and how these are differentially affected by social disadvantage and home learning environments. To contrast the impacts of early socio-economic risks and preschool home learning environments upon British children's reading abilities and academic self-concept between 7 and 10 years. n = 3,172 British children aged 3-10 years and their families. A secondary analysis of the nationally representative UK EPPE database. Multilevel structural equation modelling calculated the direct, indirect, and total impacts of early socio-economic risks (0-3 years) and preschool home learning environments (3-5 years) upon children's reading ability and academic self-concept between 7 and 10 years. Early socio-economic risk had different effects upon children's reading ability and academic self-concept. Early socio-economic risks affected children's reading at ages 7 and 10 both directly and indirectly via effects upon preschool home learning environments. By contrast, early socio-economic risks had only indirect effects upon children's academic self-concept via less stimulating home learning environments in the preschool period and by limiting reading abilities early on in primary school. Although the impacts of early socio-economic risks are larger and more easily observed upon reading than upon academic self-concept, they can impact both by making it less likely that children will experience enriching home learning environments during the preschool period. This has implications for social policymakers, early educators, and interventionists. Intervening early and improving preschool home learning environments can do more than raise children's reading abilities; secondary benefits may also be achievable upon children's self-concept. © 2017 The British Psychological Society.

Electromagnetic Reciprocity.

Energy Technology Data Exchange (ETDEWEB)

Aldridge, David F.

2014-11-01

A reciprocity theorem is an explicit mathematical relationship between two different wavefields that can exist within the same space - time configuration. Reciprocity theorems provi de the theoretical underpinning for mod ern full waveform inversion solutions, and also suggest practical strategies for speed ing up large - scale numerical modeling of geophysical datasets . In the present work, several previously - developed electromagnetic r eciprocity theorems are generalized to accommodate a broader range of medi um, source , and receiver types. Reciprocity relations enabling the interchange of various types of point sources and point receivers within a three - dimensional electromagnetic model are derived. Two numerical modeling algorithms in current use are successfully tested for adherence to reciprocity. Finally, the reciprocity theorem forms the point of departure for a lengthy derivation of electromagnetic Frechet derivatives. These mathe matical objects quantify the sensitivity of geophysical electromagnetic data to variatio ns in medium parameters, and thus constitute indispensable tools for solution of the full waveform inverse problem. ACKNOWLEDGEMENTS Sandia National Labor atories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000. Signif icant portions of the work reported herein were conducted under a Cooperative Research and Development Agreement (CRADA) between Sandia National Laboratories (SNL) and CARBO Ceramics Incorporated. The author acknowledges Mr. Chad Cannan and Mr. Terry Pa lisch of CARBO Ceramics, and Ms. Amy Halloran, manager of SNL's Geophysics and Atmospheric Sciences Department, for their interest in and encouragement of this work. Special thanks are due to Dr . Lewis C. Bartel ( recently retired from Sandia National Labo ratories

K-groups of reciprocity functors

OpenAIRE

Ivorra, Florian; Rülling, Kay

2012-01-01

In this work we introduce reciprocity functors, construct the associated K-group of a family of reciprocity functors, which itself is a reciprocity functor, and compute it in several different cases. It may be seen as a first attempt to get close to the notion of reciprocity sheaves imagined by B. Kahn. Commutative algebraic groups, homotopy invariant Nisnevich sheaves with transfers, cycle modules or K\\"ahler differentials are examples of reciprocity functors. As commutative algebraic groups...

Reciprocity is not give and take: asymmetric reciprocity to positive and negative acts.

Science.gov (United States)

Keysar, Boaz; Converse, Benjamin A; Wang, Jiunwen; Epley, Nicholas

2008-12-01

Unlike economic exchange, social exchange has no well-defined "value." It is based on the norm of reciprocity, in which giving and taking are to be repaid in equivalent measure. Although giving and taking are colloquially assumed to be equivalent actions, we demonstrate that they produce different patterns of reciprocity. In five experiments utilizing a dictator game, people reciprocated in like measure to apparently prosocial acts of giving, but reciprocated more selfishly to apparently antisocial acts of taking, even when the objective outcomes of the acts of giving and taking were identical. Additional results demonstrate that acts of giving in social exchanges are perceived as more generous than objectively identical acts of taking, that taking tends to escalate, and that the asymmetry in reciprocity is not due to gaining versus losing resources. Reciprocity appears to operate on an exchange rate that assigns value to the meaning of events, in a fashion that encourages prosocial exchanges.

Attribution and reciprocity

DEFF Research Database (Denmark)

Sebald, Alexander Christopher

2010-01-01

, in turn, influence behavior. Dufwenberg and Kirchsteiger [Dufwenberg, M., Kirchsteiger, G., 2004. A theory of sequential reciprocity. Games Econ. Behav. 47 (2), 268-298] formalize this empirical finding in their ‘theory of sequential reciprocity'. This paper extends their analysis by moves of chance. More...... precisely, an extended framework is presented which allows for the analysis of strategic interactions of reciprocal agents in situations in which material outcomes also depend on chance. Moves of chance influence the attribution of responsibilities, people's perceptions about the (un)kindness of others and......, hence, their reciprocal behavior. Furthermore, with the help of two applications it is demonstrated how this framework can be used to explain experimental findings showing that people react very differently in outcomewise-identical situations depending on the moves of chance involved....

The neural correlates of reciprocity are sensitive to prior experience of reciprocity.

Science.gov (United States)

Cáceda, Ricardo; Prendes-Alvarez, Stefania; Hsu, Jung-Jiin; Tripathi, Shanti P; Kilts, Clint D; James, G Andrew

2017-08-14

Reciprocity is central to human relationships and is strongly influenced by multiple factors including the nature of social exchanges and their attendant emotional reactions. Despite recent advances in the field, the neural processes involved in this modulation of reciprocal behavior by ongoing social interaction are poorly understood. We hypothesized that activity within a discrete set of neural networks including a putative moral cognitive neural network is associated with reciprocity behavior. Nineteen healthy adults underwent functional magnetic resonance imaging scanning while playing the trustee role in the Trust Game. Personality traits and moral development were assessed. Independent component analysis was used to identify task-related functional brain networks and assess their relationship to behavior. The saliency network (insula and anterior cingulate) was positively correlated with reciprocity behavior. A consistent array of brain regions supports the engagement of emotional, self-referential and planning processes during social reciprocity behavior. Published by Elsevier B.V.

Rayleigh reciprocity relations: Applications

International Nuclear Information System (INIS)

Lin Ju; Li Xiao-Lei; Wang Ning

2016-01-01

Classical reciprocity relations have wide applications in acoustics, from field representation to generalized optical theorem. In this paper we introduce our recent results on the applications and generalization of classical Rayleigh reciprocity relation: higher derivative reciprocity relations as a generalization of the classical one and a theoretical proof on the Green’s function retrieval from volume noises. (special topic)

Reciprocity, World Prices and Welfare

DEFF Research Database (Denmark)

Raimondos-Møller, Pascalis; Woodland, Alan D.

We examine in detail the circumstances under which reciprocity, as defined in Bagwell and Staiger (1999), leads to fixed world prices. We show that a change of tariffs satisfying reciprocity does not necessarily imply constant world prices in a world of many goods and countries. While it is possi...... of all countries, independently of whether world prices change and independently of the relative numbers of goods and countries.......We examine in detail the circumstances under which reciprocity, as defined in Bagwell and Staiger (1999), leads to fixed world prices. We show that a change of tariffs satisfying reciprocity does not necessarily imply constant world prices in a world of many goods and countries. While...... it is possible to find tariff reforms that are consistent with both reciprocity and constant world prices, these reforms do not follow from the reciprocity condition, but rather from the requirement of unchanged world prices. We propose an alternative reciprocity rule that is guaranteed to raise the welfare...

Marmoset monkeys evaluate third-party reciprocity.

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Kawai, Nobuyuki; Yasue, Miyuki; Banno, Taku; Ichinohe, Noritaka

2014-05-01

Many non-human primates have been observed to reciprocate and to understand reciprocity in one-to-one social exchanges. A recent study demonstrated that capuchin monkeys are sensitive to both third-party reciprocity and violation of reciprocity; however, whether this sensitivity is a function of general intelligence, evidenced by their larger brain size relative to other primates, remains unclear. We hypothesized that highly pro-social primates, even with a relatively smaller brain, would be sensitive to others' reciprocity. Here, we show that common marmosets discriminated between human actors who reciprocated in social exchanges with others and those who did not. Monkeys accepted rewards less frequently from non-reciprocators than they did from reciprocators when the non-reciprocators had retained all food items, but they accepted rewards from both actors equally when they had observed reciprocal exchange between the actors. These results suggest that mechanisms to detect unfair reciprocity in third-party social exchanges do not require domain-general higher cognitive ability based on proportionally larger brains, but rather emerge from the cooperative and pro-social tendencies of species, and thereby suggest this ability evolved in multiple primate lineages. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Swedish Preschool Teachers' Ideas of the Ideal Preschool Group

Science.gov (United States)

Pramling Samuelsson, Ingrid; Williams, Pia; Sheridan, Sonja; Hellman, Annette

2016-01-01

In Sweden, preschool has been noted as being of a high quality compared to many other countries. However, dramatic changes in the preschool sector are taking place. A recent law states that it is a child's right to get a preschool place within a few months. As a consequence, the number of children in preschool has increased, which could influence…

Preschool Movement Education in Turkey: Perceptions of Preschool Administrators and Parents

Science.gov (United States)

Sevimli-Celik, Serap; Kirazci, Sadettin; Ince, Mustafa Levent

2011-01-01

The purpose of this study was to examine the perceptions of preschool administrators and parents about preschool movement education and movement practices in preschools. Participants were 8 preschool administrators and 21 parents from 8 randomly selected private preschools in one of the municipalities in Ankara, Turkey. Semi-structured interviews,…

Belief in reciprocity in a Chinese sample.

Science.gov (United States)

Zhang, Zhen; Zhang, Jianxin

2012-08-01

Belief in reciprocity refers to a personally internalized faith in the reciprocity norm: that people will return positive and negative interactions or favors in kind. The current study aims to examine the relationship between belief in reciprocity and altruism among a Chinese sample. The Personal Norm of Reciprocity Scale, Trait Forgiveness Scale, Prosocial Tendency Measure, and Altruism Scale were used to assess extent of belief in reciprocity, forgiveness, and prosocial motivation, respectively, among 204 Chinese undergraduates. The results indicated that belief in reciprocity was a partially negative, but not neutral, reciprocity norm for Chinese people. Specifically, belief in reciprocity was positively related to negative reciprocity, but not significantly related to positive reciprocity. Moreover, belief in reciprocity was negatively related to both prosocial tendency and altruistic motivation. The results also indicated that forgiveness largely mediated the effect of belief in reciprocity on altruism. Finally, the implications and limitations of the current study were discussed.

Assessing executive functions in preschoolers using Shape School Task

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Marta Nieto

2016-09-01

Full Text Available Over the last two decades, there has been a growing interest in the study of the development of executive functions in preschool children due to their relationship with different cognitive, psychological, social and academic domains. Early detection of individual differences in executive functioning can have major implications for basic and applied research. Consequently, there is a key need for assessment tools adapted to preschool skills: Shape School has been shown to be a suitable task for this purpose. Our study uses Shape School as the main task to analyze development of inhibition, task-switching and working memory in a sample of 304 preschoolers (age range 3.25-6.50 years. Additionally, we include cognitive tasks for the evaluation of verbal variables (vocabulary, word reasoning and short-term memory and performance variables (picture completion and symbol search, so as to analyze their relationship with executive functions. Our results show age-associated improvements in executive functions and the cognitive variables assessed. Furthermore, correlation analyses reveal positive relationships between executive functions and the other cognitive variables. More specifically, using structural equation modeling and including age direct and indirect effects, our results suggest that executive functions explain to a greater extent performance on verbal and performance tasks. These findings provide further information to support research that considers preschool age to be a crucial period for the development of executive functions and their relationship with other cognitive processes

From Hitting to Tattling to Gossip: An Evolutionary Rationale for the Development of Indirect Aggression

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Gordon P. D. Ingram

2014-04-01

Full Text Available Adult humans are characterized by low rates of intra-group physical aggression. Since children tend to be more physically aggressive, an evolutionary developmental account shows promise for explaining how physical aggression is suppressed in adults. I argue that this is achieved partly through extended dominance hierarchies, based on indirect reciprocity and linguistic transmission of reputational information, mediated by indirectly aggressive competition. Reviewing the literature on indirect and related forms of aggression provides three pieces of evidence for the claim that evolutionarily old impulses towards physical aggression are socialized into indirect aggression in humans: (i physical aggression falls in early childhood over the same age range at which indirect aggression increases; (ii the same individuals engage in both direct and indirect aggression; and (iii socially dominant individuals practice indirect aggression more frequently. Consideration of the developmental course of indirect aggression is complemented by analysis of similar developments in verbal behaviors that are not always thought of as aggressive, namely tattling and gossip. An important puzzle concerns why indirect aggression becomes more covert, and tattling more derogated, in preadolescence and adolescence. This may be due to the development of new strategies aimed at renegotiating social identity and friendship alliances in the peer group.

From hitting to tattling to gossip: an evolutionary rationale for the development of indirect aggression.

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Ingram, Gordon P D

2014-04-29

Adult humans are characterized by low rates of intra-group physical aggression. Since children tend to be more physically aggressive, an evolutionary developmental account shows promise for explaining how physical aggression is suppressed in adults. I argue that this is achieved partly through extended dominance hierarchies, based on indirect reciprocity and linguistic transmission of reputational information, mediated by indirectly aggressive competition. Reviewing the literature on indirect and related forms of aggression provides three pieces of evidence for the claim that evolutionarily old impulses towards physical aggression are socialized into indirect aggression in humans: (i) physical aggression falls in early childhood over the same age range at which indirect aggression increases; (ii) the same individuals engage in both direct and indirect aggression; and (iii) socially dominant individuals practice indirect aggression more frequently. Consideration of the developmental course of indirect aggression is complemented by analysis of similar developments in verbal behaviors that are not always thought of as aggressive, namely tattling and gossip. An important puzzle concerns why indirect aggression becomes more covert, and tattling more derogated, in preadolescence and adolescence. This may be due to the development of new strategies aimed at renegotiating social identity and friendship alliances in the peer group.

Objectively measured sedentary behavior in preschool children: comparison between Montessori and traditional preschools.

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Byun, Wonwoo; Blair, Steven N; Pate, Russell R

2013-01-03

This study aimed to compare the levels of objectively-measured sedentary behavior in children attending Montessori preschools with those attending traditional preschools. The participants in this study were preschool children aged 4 years old who were enrolled in Montessori and traditional preschools. The preschool children wore ActiGraph accelerometers. Accelerometers were initialized using 15-second intervals and sedentary behavior was defined as Montessori preschools, after adjusting for selected potential correlates of preschoolers' sedentary behavior. Children attending Montessori preschools spent less time in sedentary behavior than those attending traditional preschools during the in-school (44.4. min/hr vs. 47.1 min/hr, P = 0.03), after-school (42.8. min/hr vs. 44.7 min/hr, P = 0.04), and total-day (43.7 min/hr vs. 45.5 min/hr, P = 0. 009) periods. School type (Montessori or traditional), preschool setting (private or public), socio-demographic factors (age, gender, and socioeconomic status) were found to be significant predictors of preschoolers' sedentary behavior. Levels of objectively-measured sedentary behavior were significantly lower among children attending Montessori preschools compared to children attending traditional preschools. Future research should examine the specific characteristics of Montessori preschools that predict the lower levels of sedentary behavior among children attending these preschools compared to children attending traditional preschools.

Low Latency Digit-Recurrence Reciprocal and Square-Root Reciprocal Algorithm and Architecture

DEFF Research Database (Denmark)

Antelo, Elisardo; Lang, Tomas; Montuschi, Paolo

2005-01-01

The reciprocal and square-root reciprocal operations are important in several applications. For these operations, we present algorithms that combine a digit-by-digit module and one iteration of a quadratic-convergence approximation. The latter is implemented by a digit-recurrence, which uses......-up of about 2 and, because of the approximation part, the area factor is also about 2. We also show a combined implementation for both operations that has essentially the same complexity as that for square-root reciprocal alone....

Non-reciprocity in nonlinear elastodynamics

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Blanchard, Antoine; Sapsis, Themistoklis P.; Vakakis, Alexander F.

2018-01-01

Reciprocity is a fundamental property of linear time-invariant (LTI) acoustic waveguides governed by self-adjoint operators with symmetric Green's functions. The break of reciprocity in LTI elastodynamics is only possible through the break of time reversal symmetry on the micro-level, and this can be achieved by imposing external biases, adding nonlinearities or allowing for time-varying system properties. We present a Volterra-series based asymptotic analysis for studying spatial non-reciprocity in a class of one-dimensional (1D), time-invariant elastic systems with weak stiffness nonlinearities. We show that nonlinearity is neither necessary nor sufficient for breaking reciprocity in this class of systems; rather, it depends on the boundary conditions, the symmetries of the governing linear and nonlinear operators, and the choice of the spatial points where the non-reciprocity criterion is tested. Extension of the analysis to higher dimensions and time-varying systems is straightforward from a mathematical point of view (but not in terms of new non-reciprocal physical phenomena), whereas the connection of non-reciprocity and time irreversibility can be studied as well. Finally, we show that suitably defined non-reciprocity measures enable optimization, and can provide physical understanding of the nonlinear effects in the dynamics, enabling one to establish regimes of "maximum nonlinearity." We highlight the theoretical developments by means of a numerical example.

Evaluating Preschool Children Knowledge about Healthy Lifestyle: Preliminary Examination of the Healthy Lifestyle Evaluation Instrument

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Grammatikopoulos, Vasilis; Konstantinidou, Elisavet; Tsigilis, Nikolaos; Zachopoulou, Evridiki; Tsangaridou, Niki; Liukkonen, Jarmo

2008-01-01

The aim of this study was to develop an instrument to evaluate the knowledge of preschool children about healthy lifestyle behavior. The innovation was that the instrument was designed to get direct evidence about healthy lifestyle from children aged 4-6 years old. Usually, children knowledge is estimated indirectly (parents, teachers), but the…

A systematic review and meta-analysis of comprehensive interventions for pre-school children with autism spectrum disorder (ASD).

Science.gov (United States)

Tachibana, Yoshiyuki; Miyazaki, Celine; Ota, Erika; Mori, Rintaro; Hwang, Yeonhee; Kobayashi, Eriko; Terasaka, Akiko; Tang, Julian; Kamio, Yoko

2017-01-01

There has an increasing number of published trials on psychosocial intervention programmes for pre-school children with autism spectrum disorder (ASD). To achieve better quality of unbiased evidence for the effectiveness of ASD interventions, it is necessary to conduct a comprehensive review that covers studies with adequate quality standards, such as randomised controlled trials (RCTs), and different types of intervention In this study, we categorize interventions for ASD as behavioural, social-communication focused, and multimodal developmental based on Howlin's classification of early interventions for children with ASD. The aim of this study was to compare these three models and investigate the strengths and weaknesses of each type of intervention and to identify the approaches that contribute to a successful outcome for children with autism. We performed a systematic review and meta-analysis. We included RCTs targeting children with ASD 6 years old or younger. A random effects model was used to present the effect estimate for the outcomes. This study also performed combined meta-analyses of all the three models to investigate the overall effectiveness of the intervention programmes. 32 randomized controlled studies were found to be eligible for inclusion. The synthesized data included 594 children from 14 RCTs. There was no statistically significant difference in the effects on autism general symptoms between the social-communication-focused model and the multimodal developmental model (p = 0.83). The results suggest that there is evidence of an effect on 'reciprocity of social interaction towards others' (standard mean difference [95% confidential interval] = 0.53[0.29,0.78], pASD have significant effects on a generalized skill to engage in reciprocal interactions with others. However, the outcomes of 'reciprocity of social interaction towards others' and 'parental synchrony' may be promising targets for interventions involving pre-school children with ASD

Detecting reciprocity at a global scale

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Frank, Morgan R.; Obradovich, Nick; Sun, Lijun; Woon, Wei Lee; LeVeck, Brad L.; Rahwan, Iyad

2018-01-01

Reciprocity stabilizes cooperation from the level of microbes all the way up to humans interacting in small groups, but does reciprocity also underlie stable cooperation between larger human agglomerations, such as nation states? Famously, evolutionary models show that reciprocity could emerge as a widespread strategy for achieving international cooperation. However, existing studies have only detected reciprocity-driven cooperation in a small number of country pairs. We apply a new method for detecting mutual influence in dynamical systems to a new large-scale data set that records state interactions with high temporal resolution. Doing so, we detect reciprocity between many country pairs in the international system and find that these reciprocating country pairs exhibit qualitatively different cooperative dynamics when compared to nonreciprocating pairs. Consistent with evolutionary theories of cooperation, reciprocating country pairs exhibit higher levels of stable cooperation and are more likely to punish instances of noncooperation. However, countries in reciprocity-based relationships are also quicker to forgive single acts of noncooperation by eventually returning to previous levels of mutual cooperation. By contrast, nonreciprocating pairs are more likely to exploit each other’s cooperation via higher rates of defection. Together, these findings provide the strongest evidence to date that reciprocity is a widespread mechanism for achieving international cooperation. PMID:29326983

Detecting reciprocity at a global scale.

Science.gov (United States)

Frank, Morgan R; Obradovich, Nick; Sun, Lijun; Woon, Wei Lee; LeVeck, Brad L; Rahwan, Iyad

2018-01-01

Reciprocity stabilizes cooperation from the level of microbes all the way up to humans interacting in small groups, but does reciprocity also underlie stable cooperation between larger human agglomerations, such as nation states? Famously, evolutionary models show that reciprocity could emerge as a widespread strategy for achieving international cooperation. However, existing studies have only detected reciprocity-driven cooperation in a small number of country pairs. We apply a new method for detecting mutual influence in dynamical systems to a new large-scale data set that records state interactions with high temporal resolution. Doing so, we detect reciprocity between many country pairs in the international system and find that these reciprocating country pairs exhibit qualitatively different cooperative dynamics when compared to nonreciprocating pairs. Consistent with evolutionary theories of cooperation, reciprocating country pairs exhibit higher levels of stable cooperation and are more likely to punish instances of noncooperation. However, countries in reciprocity-based relationships are also quicker to forgive single acts of noncooperation by eventually returning to previous levels of mutual cooperation. By contrast, nonreciprocating pairs are more likely to exploit each other's cooperation via higher rates of defection. Together, these findings provide the strongest evidence to date that reciprocity is a widespread mechanism for achieving international cooperation.

30 CFR 955.16 - Reciprocity.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Reciprocity. 955.16 Section 955.16 Mineral... AND ON INDIAN LANDS § 955.16 Reciprocity. (a) Grant of certificate. OSM shall grant an OSM blaster certificate through reciprocity to any qualified applicant who demonstrates that he or she, and whom OSM finds...

46 CFR 8.120 - Reciprocity.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Reciprocity. 8.120 Section 8.120 Shipping COAST GUARD... § 8.120 Reciprocity. (a) The Commandant may delegate authority to a classification society that has... determine reciprocity on a “case-by-case” basis. (b) In order to demonstrate that the conditions described...

Using reciprocity in Boundary Element Calculations

DEFF Research Database (Denmark)

Juhl, Peter Møller; Cutanda Henriquez, Vicente

2010-01-01

The concept of reciprocity is widely used in both theoretical and experimental work. In Boundary Element calculations reciprocity is sometimes employed in the solution of computationally expensive scattering problems, which sometimes can be more efficiently dealt with when formulated...... as the reciprocal radiation problem. The present paper concerns the situation of having a point source (which is reciprocal to a point receiver) at or near a discretized boundary element surface. The accuracy of the original and the reciprocal problem is compared in a test case for which an analytical solution...

Objectively measured sedentary behavior in preschool children: comparison between Montessori and traditional preschools

Directory of Open Access Journals (Sweden)

Byun Wonwoo

2013-01-01

Full Text Available Abstract Background This study aimed to compare the levels of objectively-measured sedentary behavior in children attending Montessori preschools with those attending traditional preschools. Methods The participants in this study were preschool children aged 4 years old who were enrolled in Montessori and traditional preschools. The preschool children wore ActiGraph accelerometers. Accelerometers were initialized using 15-second intervals and sedentary behavior was defined as Results Children attending Montessori preschools spent less time in sedentary behavior than those attending traditional preschools during the in-school (44.4. min/hr vs. 47.1 min/hr, P = 0.03, after-school (42.8. min/hr vs. 44.7 min/hr, P = 0.04, and total-day (43.7 min/hr vs. 45.5 min/hr, P = 0. 009 periods. School type (Montessori or traditional, preschool setting (private or public, socio-demographic factors (age, gender, and socioeconomic status were found to be significant predictors of preschoolers’ sedentary behavior. Conclusions Levels of objectively-measured sedentary behavior were significantly lower among children attending Montessori preschools compared to children attending traditional preschools. Future research should examine the specific characteristics of Montessori preschools that predict the lower levels of sedentary behavior among children attending these preschools compared to children attending traditional preschools.

Revisiting "The evolution of reciprocity in sizable groups": continuous reciprocity in the repeated n-person prisoner's dilemma.

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Takezawa, Masanori; Price, Michael E

2010-05-21

For many years in evolutionary science, the consensus view has been that while reciprocal altruism can evolve in dyadic interactions, it is unlikely to evolve in sizable groups. This view had been based on studies which have assumed cooperation to be discrete rather than continuous (i.e., individuals can either fully cooperate or else fully defect, but they cannot continuously vary their level of cooperation). In real world cooperation, however, cooperation is often continuous. In this paper, we re-examine the evolution of reciprocity in sizable groups by presenting a model of the n-person prisoner's dilemma that assumes continuous rather than discrete cooperation. This model shows that continuous reciprocity has a dramatically wider basin of attraction than discrete reciprocity, and that this basin's size increases with efficiency of cooperation (marginal per capita return). Further, we find that assortative interaction interacts synergistically with continuous reciprocity to a much greater extent than it does with discrete reciprocity. These results suggest that previous models may have underestimated reciprocity's adaptiveness in groups. However, we also find that the invasion of continuous reciprocators into a population of unconditional defectors becomes realistic only within a narrow parameter space in which the efficiency of cooperation is close to its maximum bound. Therefore our model suggests that continuous reciprocity can evolve in large groups more easily than discrete reciprocity only under unusual circumstances. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

The conflict of social norms may cause the collapse of cooperation: indirect reciprocity with opposing attitudes towards in-group favoritism.

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Matsuo, Tadasu; Jusup, Marko; Iwasa, Yoh

2014-04-07

Indirect reciprocity is a cooperation maintaining mechanism based on the social evaluation of players. Here, we consider the case of a group in which two social norms with opposing attitudes towards in-group favoritism are mixed. One norm, called Bushido (the way of warriors), regards cooperation with outsiders as betrayal, whereas the second norm, called Shonindo (the way of merchants), regards cooperation with outsiders as desirable. Each member of the group, irrespective of being a Bushido or a Shonindo player, is evaluated in two different ways and assigned two different labels: "ally" or "enemy" according to the Bushido evaluation; "good" or "bad" according to the Shonindo evaluation. These labels change in response to the action taken (cooperation or defection) when acting as a donor, as well as the label attached to the recipient. In addition to Bushido players, who cooperate with an ally and defect from an enemy, and Shonindo players, who cooperate with a good recipient and defect from a bad recipient, the group contains a third kind of players--unconditional defectors. The fractions of the three types of players follow the replicator dynamics. If the probability of interacting with outsiders is small, and if the cost-to-benefit ratio of cooperation is low, we observe several important patterns. Each social norm is able to maintain a high level of cooperation when dominant. Bushido and Shonindo players evaluate each other unfavorably and engage in a severe conflict. In the end, only one norm permeates the whole group driving the other to the extinction. When both social norms are equally effective, a rare occurrence of unconditional defectors may lead to a successful invasion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tacit Collusion under Fairness and Reciprocity

Directory of Open Access Journals (Sweden)

Doruk İriş

2013-02-01

Full Text Available This paper departs from the standard profit-maximizing model of firm behavior by assuming that firms are motivated in part by personal animosity–or respect–towards their competitors. A reciprocal firm responds to unkind behavior of rivals with unkind actions (negative reciprocity, while at the same time, it responds to kind behavior of rivals with kind actions (positive reciprocity. We find that collusion is easier to sustain when firms have a concern for reciprocity towards competing firms provided that they consider collusive prices to be kind and punishment prices to be unkind. Thus, reciprocity concerns among firms can have adverse welfare consequences for consumers.

Public privacy: Reciprocity and Silence

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Jenny Kennedy

2014-10-01

Full Text Available In his 1958 poem 'Dedication to my Wife' TS Eliot proclaims "these are private words addressed to you in public". Simultaneously written for his wife, Valerie Fletcher, and to the implied you of a discourse network, Eliot's poem helps to illustrate the narrative voices and silences that are constitutive of an intimate public sphere. This paper situates reciprocity as a condition of possibility for public privacy. It shows how reciprocity is enabled by systems of code operating through material and symbolic registers. Code promises to control communication, to produce neutral, systemic forms of meaning. Yet such automation is challenged by uneven and fragmented patterns of reciprocity. Moreover, examining the media of public privacy reveals historical trajectories important for understanding contemporary socio­technical platforms of reciprocity. To explore the implicit requirement of reciprocity in publicly private practices, three sites of communication are investigated framed by a media archaeology perspective: postal networks, the mail­art project PostSecret and the anonymous zine 'You'.

Organising and Leading Systematic Quality Work in the Preschool -- Preschool Managers' Perspectives

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Håkansson, Jan

2016-01-01

Preschool managers' responsibility for and leadership of systematic quality work has come to the fore in connection with changes made to the Swedish preschool curriculum. The aim of this study is to contribute to the understanding of preschool managers' leadership and management of the systematic quality work in Swedish preschools with reference…

Cooperation between Parents and Preschool Institutions through Different Concepts of Preschool Education

Directory of Open Access Journals (Sweden)

Sanja Berčnik

2017-12-01

Full Text Available This paper analyses the importance, role, and methods of cooperation between parents and preschool institutions through the different concepts of preschool education and different educational approaches and formal frameworks. Through educational approaches, the authors analyse how cooperation affects the implementation of preschool education in alternative educational approaches, such as the Waldorf, Montessori, and Reggio Emilia approaches, and Slovenian public preschool institutions. They envisage that different educational approaches in preschool education perceive the importance and role of cooperation with parents differently and conclude that there are various models of cooperation, which can be demonstrated through a theoretical analysis of the aforementioned alternative preschool approaches. In their view, partnership promotes a shared commitment to the quality realisation of educational goals; it also develops understanding and an ethos of openness in the relationship between all actors in the process of care and education of preschool children.

Capuchin Monkeys Judge Third-Party Reciprocity

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Anderson, James R.; Takimoto, Ayaka; Kuroshima, Hika; Fujita, Kazuo

2013-01-01

Increasing interest is being shown in how children develop an understanding of reciprocity in social exchanges and fairness in resource distribution, including social exchanges between third parties. Although there are descriptions of reciprocity on a one-to-one basis in other species, whether nonhumans detect reciprocity and violations of…

Imperfect information facilitates the evolution of reciprocity.

Science.gov (United States)

Kurokawa, Shun

2016-06-01

The existence of cooperation demands explanation since cooperation is costly to the actor. Reciprocity has long been regarded as a potential explanatory mechanism for the existence of cooperation. Reciprocity is a mechanism wherein a cooperator responds to an opponent's behavior by switching his/her own behavior. Hence, a possible problematic case relevant to the theory of reciprocity evolution arises when the mechanism is such that the information regarding an opponent's behavior is imperfect. Although it has been confirmed also by previous theoretical studies that imperfect information interferes with the evolution of reciprocity, this argument is based on the assumption that there are no mistakes in behavior. And, a previous study presumed that it might be expected that when such mistakes occur, reciprocity can more readily evolve in the case of imperfect information than in the case of perfect information. The reason why the previous study considers so is that in the former case, reciprocators can miss defections incurred by other reciprocators' mistakes due to imperfect information, allowing cooperation to persist when such reciprocators meet. However, contrary to this expectation, the previous study has shown that even when mistakes occur, imperfect information interferes with the evolution of reciprocity. Nevertheless, the previous study assumed that payoffs are linear (i.e., that the effect of behavior is additive and there are no synergetic effects). In this study, we revisited the same problem but removed the assumption that payoffs are linear. We used evolutionarily stable strategy analysis to compare the condition for reciprocity to evolve when mistakes occur and information is imperfect with the condition for reciprocity to evolve when mistakes occur and information is perfect. Our study revealed that when payoffs are not linear, imperfect information can facilitate the evolution of reciprocity when mistakes occur; while when payoffs are linear

Preschool Teachers' Emotional Socialization Responses to 4-6 Year-Old Turkish Preschoolers' Emotional Expressions

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Kilic, Sukran

2015-01-01

The goal of the present study was to investigate preschool teachers' emotion socialization responses to Turkish preschoolers' emotional expressions based on children's age and gender. The participants in the current study were 12 preschool full time teachers from 4 preschool and 288 preschoolers ranging in age from 4 to 6 years in Aksaray. In…

Reciprocating Linear Electric Motor

Science.gov (United States)

Goldowsky, M. P.

1984-01-01

Features include structural simplicity and good force/displacement characteristics. Reciprocating motor has simple, rugged construction, relatively low reciprocating weight, improved power delivery, and improved force control. Wear reduced by use of magnetic bearings. Intended to provide drivers for long-lived Stirling-cycle cryogenic refrigerators, concept has less exotic applications, such as fuel pumps.

Reciprocity of agonistic support in ravens.

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Fraser, Orlaith N; Bugnyar, Thomas

2012-01-01

Cooperative behaviour through reciprocation or interchange of valuable services in primates has received considerable attention, especially regarding the timeframe of reciprocation and its ensuing cognitive implications. Much less, however, is known about reciprocity in other animals, particularly birds. We investigated patterns of agonistic support (defined as a third party intervening in an ongoing conflict to attack one of the conflict participants, thus supporting the other) in a group of 13 captive ravens, Corvus corax. We found support for long-term, but not short-term, reciprocation of agonistic support. Ravens were more likely to support individuals who preened them, kin and dominant group members. These results suggest that ravens do not reciprocate on a calculated tit-for-tat basis, but aid individuals from whom reciprocated support would be most useful and those with whom they share a good relationship. Additionally, dyadic levels of agonistic support and consolation (postconflict affiliation from a bystander to the victim) correlated strongly with each other, but we found no evidence to suggest that receiving agonistic support influences the victim's likelihood of receiving support (consolation) after the conflict ends. Our findings are consistent with an emotionally mediated form of reciprocity in ravens and provide additional support for convergent cognitive evolution in birds and mammals.

Reciprocity Outperforms Conformity to Promote Cooperation.

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Romano, Angelo; Balliet, Daniel

2017-10-01

Evolutionary psychologists have proposed two processes that could give rise to the pervasiveness of human cooperation observed among individuals who are not genetically related: reciprocity and conformity. We tested whether reciprocity outperformed conformity in promoting cooperation, especially when these psychological processes would promote a different cooperative or noncooperative response. To do so, across three studies, we observed participants' cooperation with a partner after learning (a) that their partner had behaved cooperatively (or not) on several previous trials and (b) that their group members had behaved cooperatively (or not) on several previous trials with that same partner. Although we found that people both reciprocate and conform, reciprocity has a stronger influence on cooperation. Moreover, we found that conformity can be partly explained by a concern about one's reputation-a finding that supports a reciprocity framework.

The Structure of Reciprocity

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Molm, Linda D.

2010-01-01

Reciprocity is one of the defining features of social exchange and social life, yet exchange theorists have tended to take it for granted. Drawing on work from a decade-long theoretical research program, I argue that reciprocity is structured and variable across different forms of exchange, that these variations in the structure of reciprocity…

Static non-reciprocity in mechanical metamaterials.

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Coulais, Corentin; Sounas, Dimitrios; Alù, Andrea

2017-02-23

Reciprocity is a general, fundamental principle governing various physical systems, which ensures that the transfer function-the transmission of a physical quantity, say light intensity-between any two points in space is identical, regardless of geometrical or material asymmetries. Breaking this transmission symmetry offers enhanced control over signal transport, isolation and source protection. So far, devices that break reciprocity (and therefore show non-reciprocity) have been mostly considered in dynamic systems involving electromagnetic, acoustic and mechanical wave propagation associated with fields varying in space and time. Here we show that it is possible to break reciprocity in static systems, realizing mechanical metamaterials that exhibit vastly different output displacements under excitation from different sides, as well as one-way displacement amplification. This is achieved by combining large nonlinearities with suitable geometrical asymmetries and/or topological features. In addition to extending non-reciprocity and isolation to statics, our work sheds light on energy propagation in nonlinear materials with asymmetric crystalline structures and topological properties. We anticipate that breaking reciprocity will open avenues for energy absorption, conversion and harvesting, soft robotics, prosthetics and optomechanics.

Child Sexual Abuse at Preschools--A Research Review of a Complex Issue for Preschool Professionals

Science.gov (United States)

Bergström, Helena; Eidevald, Christian; Westberg-Broström, Anna

2016-01-01

The objective of this research review is to synthesize research published between 2000 and 2015 regarding child sexual abuse, preschool and preschool teachers. The review identifies themes relevant for the preschool teacher profession: child sexual abuse at preschools, suspicions and consequences for the preschool sector, preventing techniques and…

Reciprocity in therapeutic relationships: A conceptual review.

Science.gov (United States)

Sandhu, Sima; Arcidiacono, Eleonora; Aguglia, Eugenio; Priebe, Stefan

2015-12-01

Reciprocity has generally been understood as a process of giving and taking, within an exchange of emotions or services, and has long been recognized as a central part of human life. However, an understanding of reciprocity in professional helping relationships has seldom received attention, despite movements in mental health care towards more collaborative approaches between service users and professionals. In this review, a systematic search of the published papers was conducted in order to explore how reciprocity is conceptualized and understood as part of the dyadic therapeutic relationship between professionals and service users. Eleven papers met our inclusion criteria and a narrative synthesis was used to synthesize the key concepts of reciprocity. The concepts of: 'dynamic equilibrium', 'shared affect', 'asymmetric alliance', and 'recognition as a fellow human being' were recurrent in understandings of reciprocity in professional contexts. These conceptualizations of reciprocity were also linked to specific behavioural and psychological processes. The findings suggest that reciprocity may be conceptualized and incorporated as a component of mental health care, with recurrent and observable processes which may be harnessed to promote positive outcomes for service users. To this end, we make recommendations for further research to progress and develop reciprocal processes in mental health care. © 2015 Australian College of Mental Health Nurses Inc.

Reciprocity in quantum, electromagnetic and other wave scattering

International Nuclear Information System (INIS)

Deák, L.; Fülöp, T.

2012-01-01

The reciprocity principle is that, when an emitted wave gets scattered on an object, the scattering transition amplitude does not change if we interchange the source and the detector—in other words, if incoming waves are interchanged with appropriate outgoing ones. Reciprocity is sometimes confused with time reversal invariance, or with invariance under the rotation that interchanges the location of the source and the location of the detector. Actually, reciprocity covers the former as a special case, and is fundamentally different from–but can be usefully combined with–the latter. Reciprocity can be proved as a theorem in many situations and is found violated in other cases. The paper presents a general treatment of reciprocity, discusses important examples, shows applications in the field of photon (Mössbauer) scattering, and establishes a fruitful connection with a recently developing area of mathematics. - Highlights: ► A frame independent generalized reciprocity theorem of scattering theory is given. ► Reciprocity for two spin/polarization degrees of freedom is detailed. ► Relationship of reciprocity to time reversal and to 180 degree rotation is discussed. ► Reciprocal and nonreciprocal settings in Mossbauer spectroscopy are studied. ► The symmetry of diffuse omega-scans is explained with the aid of reciprocity.

Reciprocity principle in duct acoustics

Science.gov (United States)

Cho, Y.-C.

1979-01-01

Various reciprocity relations in duct acoustics have been derived on the basis of the spatial reciprocity principle implied in Green's functions for linear waves. The derivation includes the reciprocity relations between mode conversion coefficients for reflection and transmission in nonuniform ducts, and the relation between the radiation of a mode from an arbitrarily terminated duct and the absorption of an externally incident plane wave by the duct. Such relations are well defined as long as the systems remain linear, regardless of acoustic properties of duct nonuniformities which cause the mode conversions.

Structural Behaviour of Reciprocal Structures

DEFF Research Database (Denmark)

Parigi, Dario; Kirkegaard, Poul Henning

2013-01-01

The present paper focuses on the comparison of several two-dimensional and three-dimensional reciprocal configurations. The goal of such comparison is to analyse the structural behaviour when changing the geometric parameters used to describe the geometry of reciprocal structures....

Free-Form Kinetic Reciprocal System

DEFF Research Database (Denmark)

Parigi, Dario; Sassone, Mario

2011-01-01

Kinetic Reciprocal System (KRS) are innovative moveable structures based on the principle of reciprocity [1] with internal pin-slot constraints [2]. The analysis of KRS kinematic and static determinacy is developed through the construction of kinematic matrices, accordingly with [3] and a discuss...

Towards a unified theory of reciprocity.

Science.gov (United States)

Rosas, Alejandro

2012-02-01

In a unified theory of human reciprocity, the strong and weak forms are similar because neither is biologically altruistic and both require normative motivation to support cooperation. However, strong reciprocity is necessary to support cooperation in public goods games. It involves inflicting costs on defectors; and though the costs for punishers are recouped, recouping costs requires complex institutions that would not have emerged if weak reciprocity had been enough.

23 CFR 1235.8 - Reciprocity.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Reciprocity. 1235.8 Section 1235.8 Highways NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION AND FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION GUIDELINES UNIFORM SYSTEM FOR PARKING FOR PERSONS WITH DISABILITIES § 1235.8 Reciprocity. The State system...

Neural correlate of human reciprocity in social interactions.

Science.gov (United States)

Sakaiya, Shiro; Shiraito, Yuki; Kato, Junko; Ide, Hiroko; Okada, Kensuke; Takano, Kouji; Kansaku, Kenji

2013-01-01

Reciprocity plays a key role maintaining cooperation in society. However, little is known about the neural process that underpins human reciprocity during social interactions. Our neuroimaging study manipulated partner identity (computer, human) and strategy (random, tit-for-tat) in repeated prisoner's dilemma games and investigated the neural correlate of reciprocal interaction with humans. Reciprocal cooperation with humans but exploitation of computers by defection was associated with activation in the left amygdala. Amygdala activation was also positively and negatively correlated with a preference change for human partners following tit-for-tat and random strategies, respectively. The correlated activation represented the intensity of positive feeling toward reciprocal and negative feeling toward non-reciprocal partners, and so reflected reciprocity in social interaction. Reciprocity in social interaction, however, might plausibly be misinterpreted and so we also examined the neural coding of insight into the reciprocity of partners. Those with and without insight revealed differential brain activation across the reward-related circuitry (i.e., the right middle dorsolateral prefrontal cortex and dorsal caudate) and theory of mind (ToM) regions [i.e., ventromedial prefrontal cortex (VMPFC) and precuneus]. Among differential activations, activation in the precuneus, which accompanied deactivation of the VMPFC, was specific to those without insight into human partners who were engaged in a tit-for-tat strategy. This asymmetric (de)activation might involve specific contributions of ToM regions to the human search for reciprocity. Consequently, the intensity of emotion attached to human reciprocity was represented in the amygdala, whereas insight into the reciprocity of others was reflected in activation across the reward-related and ToM regions. This suggests the critical role of mentalizing, which was not equated with reward expectation during social interactions.

Neural correlate of human reciprocity in social interactions

Directory of Open Access Journals (Sweden)

Shiro eSakaiya

2013-12-01

Full Text Available Reciprocity plays a key role maintaining cooperation in society. However, little is known about the neural process that underpins human reciprocity during social interactions. Our neuroimaging study manipulated partner identity (computer, human and strategy (random, tit-for-tat in repeated prisoner’s dilemma games and investigated the neural correlate of reciprocal interaction with humans. Reciprocal cooperation with humans but exploitation of computers by defection was associated with activation in the left amygdala. Amygdala activation was also positively and negatively correlated with a preference change for human partners following tit-for-tat and random strategies, respectively. The correlated activation represented the intensity of positive feeling toward reciprocal and negative feeling toward non-reciprocal partners, and so reflected reciprocity in social interaction. Reciprocity in social interaction, however, might plausibly be misinterpreted and so we also examined the neural coding of insight into the reciprocity of partners. Those with and without insight revealed differential brain activation across the reward-related circuitry (i.e., the right middle dorsolateral prefrontal cortex and dorsal caudate and theory of mind (ToM regions (i.e., ventromedial prefrontal cortex [VMPFC] and precuneus. Among differential activations, activation in the precuneus, which accompanied deactivation of the VMPFC, was specific to those without insight into human partners who were engaged in a tit-for-tat strategy. This asymmetric (deactivation might involve specific contributions of ToM regions to the human search for reciprocity. Consequently, the intensity of emotion attached to human reciprocity was represented in the amygdala, whereas insight into the reciprocity of others was reflected in activation across the reward-related and ToM regions. This suggests the critical role of mentalizing, which was not equated with reward expectation during

33 CFR 173.17 - Reciprocity.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Reciprocity. 173.17 Section 173.17 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY VESSEL NUMBERING AND CASUALTY AND ACCIDENT REPORTING Numbering § 173.17 Reciprocity. (a) Section...

49 CFR 384.214 - Reciprocity.

Science.gov (United States)

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Reciprocity. 384.214 Section 384.214 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY... Reciprocity. The State shall allow any person to operate a CMV in the State who is not disqualified from...

An Examination of Parents' and Preschool Workers' Perspectives on Bullying in Preschool

Science.gov (United States)

Cameron, David Lansing; Kovac, Velibor Bobo

2016-01-01

Parents (n = 141) and preschool workers (n = 81) completed a survey regarding their perspectives towards: (a) the existence of bullying in preschool, (b) interpretations of bullying, (c) the roles of bullies and victims, and (d) gender differences. Findings suggest that both groups largely believe that bullying occurs in preschool. Excluding…

Joint effects of asymmetric payoff and reciprocity mechanisms on collective cooperation in water sharing interactions: a game theoretic perspective.

Directory of Open Access Journals (Sweden)

Cho Nam Ng

Full Text Available Common-pool resource (CPR dilemmas distinguish themselves from general public good problems by encompassing both social and physical features. This paper examines how a physical mechanism, namely asymmetric payoff; and a social mechanism, reciprocity; simultaneously affect collective cooperation in theoretical water sharing interactions. We present an iterative N-person game theoretic model to investigate the joint effects of these two mechanisms in a linear fully connected river system under three information assumptions. From a simple evolutionary perspective, this paper quantitatively addresses the conditions for Nash Equilibrium in which collective cooperation might be established. The results suggest that direct reciprocity increases every actor's motivation to contribute to the collective good of the river system. Meanwhile, various upstream and downstream actors manifest individual disparities as a result of the direct reciprocity and asymmetric payoff mechanisms. More specifically, the downstream actors are less willing to cooperate unless there is a high probability that long-term interactions are ensured; however, a greater level of asymmetries is likely to increase upstream actors' incentives to cooperate even though the interactions could quickly end. The upstream actors also display weak sensitivity to an increase in the total number of actors, which generally results in a reduction in the other actors' motivation for cooperation. It is also shown that the indirect reciprocity mechanism relaxes the overall conditions for cooperative Nash Equilibrium.

The specificity of reciprocity: Young children reciprocate more generously to those who intentionally benefit them.

Science.gov (United States)

Vaish, Amrisha; Hepach, Robert; Tomasello, Michael

2018-03-01

Young children engage in direct reciprocity, but the mechanisms underlying such reciprocity remain unclear. In particular, prior work leaves unclear whether children's reciprocity is simply a response to receiving benefits (regardless of whether the benefits were intended) or driven by a mechanism of rewarding or preferring all benefactors (regardless of whom they benefited). Alternatively, perhaps children engage in genuine reciprocity such that they are particularly prosocial toward benefactors who intentionally provided them with benefits. Our findings support this third, richer possibility; the 3-year-olds who received benefits through the good intentions of a benefactor were subsequently more generous toward the benefactor than children who either (a) received the same benefits from the benefactor unintentionally or (b) observed the benefactor bestow the same benefits on another individual. Thus, young children are especially motivated to benefit those who have demonstrated goodwill toward them, suggesting, as one possible mechanism, an early sense of gratitude. Copyright © 2017 Elsevier Inc. All rights reserved.

An Inquiry into Relationship Suicides and Reciprocity

Science.gov (United States)

Davis, Mark S.; Callanan, Valerie J.; Lester, David; Haines, Janet

2009-01-01

Few theories on suicide have been grounded in the norm of reciprocity. There is literature on suicide, however, describing motivations such as retaliation and retreat which can be interpreted as modes of adaptation to the norm of reciprocity. We propose a reciprocity-based theory to explain suicides associated with relationship problems. Employing…

Electromagnetic reciprocity in antenna theory

CERN Document Server

Stumpf, Martin

2018-01-01

The reciprocity theorem is among the most intriguing concepts in wave field theory and has become an integral part of almost all standard textbooks on electromagnetic (EM) theory. This book makes use of the theorem to quantitatively describe EM interactions concerning general multiport antenna systems. It covers a general reciprocity-based description of antenna systems, their EM scattering properties, and further related aspects. Beginning with an introduction to the subject, Electromagnetic Reciprocity in Antenna Theory provides readers first with the basic prerequisites before offering coverage of the equivalent multiport circuit antenna representations, EM coupling between multiport antenna systems and their EM interactions with scatterers, accompanied with the corresponding EM compensation theorems.

On Reciprocal Causation in the Evolutionary Process.

Science.gov (United States)

Svensson, Erik I

2018-01-01

Recent calls for a revision of standard evolutionary theory (SET) are based partly on arguments about the reciprocal causation. Reciprocal causation means that cause-effect relationships are bi-directional, as a cause could later become an effect and vice versa. Such dynamic cause-effect relationships raise questions about the distinction between proximate and ultimate causes, as originally formulated by Ernst Mayr. They have also motivated some biologists and philosophers to argue for an Extended Evolutionary Synthesis (EES). The EES will supposedly expand the scope of the Modern Synthesis (MS) and SET, which has been characterized as gene-centred, relying primarily on natural selection and largely neglecting reciprocal causation. Here, I critically examine these claims, with a special focus on the last conjecture. I conclude that reciprocal causation has long been recognized as important by naturalists, ecologists and evolutionary biologists working in the in the MS tradition, although it it could be explored even further. Numerous empirical examples of reciprocal causation in the form of positive and negative feedback are now well known from both natural and laboratory systems. Reciprocal causation have also been explicitly incorporated in mathematical models of coevolutionary arms races, frequency-dependent selection, eco-evolutionary dynamics and sexual selection. Such dynamic feedback were already recognized by Richard Levins and Richard Lewontin in their bok The Dialectical Biologist . Reciprocal causation and dynamic feedback might also be one of the few contributions of dialectical thinking and Marxist philosophy in evolutionary theory. I discuss some promising empirical and analytical tools to study reciprocal causation and the implications for the EES. Finally, I briefly discuss how quantitative genetics can be adapated to studies of reciprocal causation, constructive inheritance and phenotypic plasticity and suggest that the flexibility of this approach

When Does Preschool Matter?

Science.gov (United States)

Yoshikawa, Hirokazu; Weiland, Christina; Brooks-Gunn, Jeanne

2016-01-01

We have many reasons to invest in preschool programs, including persistent gaps in school readiness between children from poorer and wealthier families, large increases in maternal employment over the past several decades, and the rapid brain development that preschool-age children experience. But what do we know about preschool education's…

Preschool education studentsʼ attitude towards inclusion in preschool educational context

OpenAIRE

Skubic, Darija; Vidrih, Alenka

2015-01-01

The purpose of the current study was to investigate the attitudes of preschool education students regarding inclusive teaching/inclusive practices. As a research instrument a questionnaire with 17 statements, referred to education, practices and policies of inclusion was developed. 118 students of the preschool education study programme at the Faculty of Education in Ljubljana participated in the study. There were 3 different groups of students: 25 students of the 2nd year of preschool educat...

Assessment of Attention in Preschoolers

Science.gov (United States)

Mahone, E.M.; Schneider, H.E.

2012-01-01

In the past two decades, there has been an increased interest in the assessment and treatment of preschool children presenting with concerns about attention problems. This article reviews the research and clinical literature involving assessment of attention and related skills in the preschool years. While inattention among preschoolers is common, symptoms alone do not necessarily indicate a disorder, and most often represent a normal variation in typical preschool child development. Thus, accurate identification of “disordered” attention in preschoolers can be challenging, and development of appropriate, norm-referenced tests of attention for preschoolers is also difficult. The current review suggests that comprehensive assessment of attention and related functions in the preschool child should include thorough review of the child’s history, planned observations, and formal psychometric testing. The three primary methods of psychometric assessment that have been used to characterize attentional functioning in preschool children include performance-based tests, structured caregiver interviews, and rating scales (parent, teacher, and clinician). Among performance-based methods for measurement of attention in the preschool years, tests have been developed to assess sustained attention, selective (focused) attention, span of attention (encoding/manipulation), and (top-down) controlled attention—including freedom from distractibility and set shifting. Many of these tests remain experimental in nature, and review of published methods yields relatively few commercially available, nationally normed tests of attention for preschoolers, and an overall dearth of reliability and validity studies on the available measures. PMID:23090646

Aggression and withdrawal related behavior within conflict management progression in preschool boys with language impairment.

Science.gov (United States)

Horowitz, Laura; Westlund, Karolina; Ljungberg, Tomas

2007-10-01

This study examined conflict behavior in naturalistic preschool settings to better understand the role of non-affiliative behavior and language in conflict management. Free-play at preschool was filmed among 20 boys with typically developing language (TL) and among 11 boys with Language Impairment (LI); the boys 4-7 years old. Conflict behavior was coded and analyzed with a validated system. Post-conflict non-affiliative behavior (aggression and withdrawal) displays, and the links between the displays and reconciliation (i.e., former opponents exchange friendly behavioral shortly after conflict termination) was examined. Group comparisons revealed boys with LI displayed aggression in a smaller share of conflicts, but exhibited [Symbol: see text]active' withdrawal (left the room), in a larger conflict share. Boys with TL overcame aggression (more common TL behavior) and after reconciled, to a greater extent than the boys with LI after active withdrawal (more common LI behavior). Also, after reciprocal or only verbal aggression, boys with LI reconciled to a lesser extent than boys with TL. The boys with LI demonstrated difficulties confronting conflict management, as well as concluding emotionally heightened and aggressive behavioral turns.

Process Mediates Structure: The Relation between Preschool Teacher Education and Preschool Teachers' Knowledge

Science.gov (United States)

Blömeke, Sigrid; Jenßen, Lars; Grassmann, Marianne; Dunekacke, Simone; Wedekind, Hartmut

2017-01-01

Data about processes and outcomes of preschool teacher education is scarce. This paper examines the opportunities to learn (OTL) of prospective preschool teachers (N = 1,851) at different types and stages of preschool teacher education and their relation to general pedagogical knowledge (GPK), mathematics pedagogical content knowledge (MPCK), and…

36 CFR 251.63 - Reciprocity.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Reciprocity. 251.63 Section 251.63 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LAND USES Special Uses § 251.63 Reciprocity. If it is determined that a right-of-way shall be needed by the United States...

Teacher License Reciprocity. 50-State Review

Science.gov (United States)

Aragon, Stephanie

2017-01-01

This policy report defines and provides a 50-state review of teacher license reciprocity, explores how state-specific licensing requirements impact the teacher labor market, and includes examples of national and state efforts to facilitate reciprocity.

Reciprocity Effects in the Trust Game

Directory of Open Access Journals (Sweden)

Alexander Smith

2013-07-01

Full Text Available I use data from a previous experiment for classifying subjects based on their behavior in the trust game. Prior literature defines a “reciprocity effect” as the tendency for Second Movers to return proportions increasing in the amounts that they receive. In the data that I use, 31% of Second Movers show reciprocity effects, 31% are neutral, and 25% consistently free-ride, indicating that the aggregate reciprocity effect for the sample as a whole is attributable to a minority of the subjects.

Preschool Teachers' Views on Competence in the Context of Home and Preschool Collaboration

Science.gov (United States)

Vuorinen, Tuula; Sandberg, Anette; Sheridan, Sonja; Williams, Pia

2014-01-01

The purpose of this article is to analyse and discuss preschool teachers' views regarding competence within their profession in the context of home and preschool collaboration. The question addressed is as follows: In what situations do preschool teachers perceive that their competence becomes visible for parents? The results, based on interviews…

Profit Sharing and Reciprocity: Theory and Survey Evidence

OpenAIRE

Cornelissen, Thomas; Heywood, John S.; Jirjahn, Uwe

2010-01-01

The 1/n problem potentially limits the effectiveness of profit sharing in motivating workers. While the economic literature suggests that reciprocity can mitigate this problem, it remains silent on the optimal degree of reciprocity. We present a representative model demonstrating that reciprocity may increase productive effort but may also increase unproductive effort such as socializing on the job. The model implies that reciprocity increases profit up to a point but decreases profit beyond ...

Development of the reciprocity of self-disclosure.

Science.gov (United States)

Rotenberg, K J; Chase, N

1992-03-01

This study was designed to assess whether children demonstrate covariant and equivalent forms of the reciprocity of self-disclosure, and if so, at what age. Twenty-one kindergarten, 23 second-grade, 24 fourth-grade, and 24 sixth-grade children were shown videotapes of three children (partners) who provided pre-established low-, medium-, and high-intimate disclosures. The subjects were required to send a message to the partners on topics varying in personal content. Fourth-grade children showed evidence of covariant reciprocity of self-disclosure by disclosing higher intimacy to high-intimate partners than to low-intimate partners. Sixth-grade children showed equivalent reciprocity of self-disclosure by providing a greater number of high- and medium-intimate disclosures to high- and medium-intimate partners, respectively, than to low-intimate partners. By contrast, neither form of reciprocity of self-disclosure was shown by kindergarten and second-grade children. Consistent with our expectations, girls provided a greater number of high-intimate disclosures than did boys in three of the four grades. The findings are discussed in terms of interplay between the development of the reciprocity of self-disclosure and the norm of the reciprocity of self-disclosure.

Structural Equation Modeling of the Effects of Family, Preschool, and Stunting on the Cognitive Development of School Children

Directory of Open Access Journals (Sweden)

Oluwakemi Rachel Ajayi

2017-05-01

Full Text Available A recent study based on a sample of 1,580 children from five adjacent geographical locations in KwaZulu-Natal, South Africa, was carried out to examine the association of nutrition, family influence, preschool education, and disadvantages in geographical location with the cognitive development of school children. Data were collected on the children from 2009 to 2011 for this developmental study and included cognitive scores and information on the health and nutrition of the children. The current study analyzed the association of demographic variables (geographical location (site, child variables (sex, preschool education and socioeconomic status, parental level of education (maternal and paternal, child’s health (HIV status and hemoglobin level and anthropometric measures of nutritional status (height-for-age with children’s cognitive outcomes. The hypothesis is that the nutritional status of children is a pathway through which the indirect effects of the variables of interest exert influence on their cognitive outcomes. Factor analysis based on principal components was used to create a variable based on the cognitive measures, correlations were used to examine the bivariate association between the variables of interest in the preliminary analysis and a path analysis was constructed, which was used for the disaggregation of the direct and indirect effects of the predictors for each cognitive test in a structural equation model. The results revealed that nutritional status directly predicts cognitive test scores and is a path through which other variables indirectly influence children’s cognitive outcome and development.

Reciprocal Relationships: Something for Everyone.

Science.gov (United States)

Tumosa, Nina

2017-01-01

Reciprocal relationships based on mutual goals, respect and trust are key to maintaining working relationships and getting reliable research results. Yet relationship building is not a concept taught in academia. These skills are often learned the hard way, with singular solutions found for case-by-case scenarios. Several journeys to identify the components, barriers and rewards of reciprocal relationships are discussed.

Trust and Reciprocity: Are Effort and Money Equivalent?

Science.gov (United States)

Vilares, Iris; Dam, Gregory; Kording, Konrad

2011-01-01

Trust and reciprocity facilitate cooperation and are relevant to virtually all human interactions. They are typically studied using trust games: one subject gives (entrusts) money to another subject, which may return some of the proceeds (reciprocate). Currently, however, it is unclear whether trust and reciprocity in monetary transactions are similar in other settings, such as physical effort. Trust and reciprocity of physical effort are important as many everyday decisions imply an exchange of physical effort, and such exchange is central to labor relations. Here we studied a trust game based on physical effort and compared the results with those of a computationally equivalent monetary trust game. We found no significant difference between effort and money conditions in both the amount trusted and the quantity reciprocated. Moreover, there is a high positive correlation in subjects' behavior across conditions. This suggests that trust and reciprocity may be character traits: subjects that are trustful/trustworthy in monetary settings behave similarly during exchanges of physical effort. Our results validate the use of trust games to study exchanges in physical effort and to characterize inter-subject differences in trust and reciprocity, and also suggest a new behavioral paradigm to study these differences. PMID:21364931

Reciprocity in electron diffraction

International Nuclear Information System (INIS)

Gunning, J.; Goodman, P.

1992-01-01

The symmetry of reciprocity is reviewed in the context of relativistic quantum mechanics with the specific aim of relating to C, P and T invariances. From this investigation global time reversal is found to be a sufficient condition for reciprocity to hold in scattering from a vector potential. The present proof is free from assumptions of small-angle scattering and from restrictions on z-dependent terms in the scattering equation, and by avoiding S-matrix theory is thought to be accessible to undergraduate teaching. (orig.)

Alternative energy efficient membrane bioreactor using reciprocating submerged membrane.

Science.gov (United States)

Ho, J; Smith, S; Roh, H K

2014-01-01

A novel membrane bioreactor (MBR) pilot system, using membrane reciprocation instead of air scouring, was operated at constant high flux and daily fluctuating flux to demonstrate its application under peak and diurnal flow conditions. Low and stable transmembrane pressure was achieved at 40 l/m(2)/h (LMH) by use of repetitive membrane reciprocation. The results reveal that the inertial forces acting on the membrane fibers effectively propel foulants from the membrane surface. Reciprocation of the hollow fiber membrane is beneficial for the constant removal of solids that may build up on the membrane surface and inside the membrane bundle. The membrane reciprocation in the reciprocating MBR pilot consumed less energy than coarse air scouring used in conventional MBR systems. Specific energy consumption for the membrane reciprocation was 0.072 kWh/m(3) permeate produced at 40 LMH flux, which is 75% less than for a conventional air scouring system as reported in literature without consideration of energy consumption for biological aeration (0.29 kWh/m(3)). The daily fluctuating flux test confirmed that the membrane reciprocation is effective to handle fluctuating flux up to 50 LMH. The pilot-scale reciprocating MBR system successfully demonstrated that fouling can be controlled via 0.43 Hz membrane reciprocation with 44 mm or higher amplitude.

Laying a Firm Foundation: Embedding Evidence-Based Emergent Literacy Practices Into Early Intervention and Preschool Environments.

Science.gov (United States)

Terrell, Pamela; Watson, Maggie

2018-04-05

As part of this clinical forum on curriculum-based intervention, the goal of this tutorial is to share research about the importance of language and literacy foundations in natural environments during emergent literacy skill development, from infancy through preschool. Following an overview of intervention models in schools by Powell (2018), best practices at home, in child care, and in preschool settings are discussed. Speech-language pathologists in these settings will be provided a toolbox of best emergent literacy practices. A review of published literature in speech-language pathology, early intervention, early childhood education, and literacy was completed. Subsequently, an overview of the impact of early home and preschool literacy experiences are described. Research-based implementation of best practice is supported with examples of shared book reading and child-led literacy embedded in play within the coaching model of early intervention. Finally, various aspects of emergent literacy skill development in the preschool years are discussed. These include phonemic awareness, print/alphabet awareness, oral language skills, and embedded/explicit literacy. Research indicates that rich home literacy environments and exposure to rich oral language provide an important foundation for the more structured literacy environments of school. Furthermore, there is a wealth of evidence to support a variety of direct and indirect intervention practices in the home, child care, and preschool contexts to support and enhance all aspects of oral and written literacy. Application of this "toolbox" of strategies should enable speech-language pathologists to address the prevention and intervention of literacy deficits within multiple environments during book and play activities. Additionally, clinicians will have techniques to share with parents, child care providers, and preschool teachers for evidence-based literacy instruction within all settings during typical daily

32 CFR 634.16 - Reciprocal state-military action.

Science.gov (United States)

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Reciprocal state-military action. 634.16 Section... Reciprocal state-military action. (a) Commanders will recognize the interests of the states in matters of POV... formal military reciprocity, the procedures below will be adopted: (1) Commanders will recognize official...

On reciprocal Baecklund transformations of inverse scattering schemes

International Nuclear Information System (INIS)

Rogers, C.; Wong, P.

1984-01-01

The notion of reciprocally related inverse scattering schemes is introduced and is shown to be a key component in the link between the AKNS and WKI schemes. Reciprocal auto-Baecklund transformations are represented both for a generalised Harry-Dym equation and an equation descriptive of nonlinear oscillation of elastic beams. Further, the N-loop soliton solution of the KIW equation is generated in a convenient parametric form via reciprocal Baecklund transformations. Finally, an important reduction to canonical spectral form is shown to be a reciprocal transformation. (Auth.)

Effect of Glide Path Creating on Cyclic Fatigue Resistance of Reciproc and Reciproc Blue Nickel-titanium Files: A Laboratory Study.

Science.gov (United States)

Özyürek, Taha; Uslu, Gülşah; Yılmaz, Koray; Gündoğar, Mustafa

2018-06-01

The purpose of this article was to compare the cyclic fatigue resistance of Reciproc and Reciproc Blue files (VDW GmbH, Munich, Germany) that were used to prepare root canals of mandibular molar teeth with or without a glide path. Sixty Reciproc R25 and 60 Reciproc Blue R25 files were used. The Reciproc and Reciproc Blue groups were divided into 3 subgroups (ie, as received condition, used without a glide path, and used with a glide path). All the instruments were rotated in a stainless steel artificial canal with an inner diameter of 1.5 mm, a 60° angle of curvature, and a radius of curvature of 5 mm until fracture occurred. The number of cycle to fracture was calculated, and the length of the fractured segments was measured. The Kruskal-Wallis test was performed to statistically analyze the data using SPSS 21.0 software (IBM Corp, Armonk, NY) at a 5% significance level. The cyclic fatigue resistance of as received condition Reciproc Blue files was found to be higher than as received condition Reciproc files (P  .05). There was no statistically significant difference in the mean length of the fractured fragments of the instruments (P > .05). Within the limitations of this in vitro study, it was concluded that creating a glide path using ProGlider files had no effect on the cyclic fatigue resistance of RPC and RPC Blue files. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The role of preschool teacher-child interactions in academic adjustment: An intervention study with Playing-2-gether.

Science.gov (United States)

Van Craeyevelt, Sanne; Verschueren, Karine; Vancraeyveldt, Caroline; Wouters, Sofie; Colpin, Hilde

2017-09-01

Social relationships can serve as important risk or protective factors for child development in general, and academic adjustment in particular. This study investigated the role of teacher-child interactions in academic adjustment among preschool boys at risk of externalizing behaviour, using a randomized controlled trial study with Playing-2-gether (P2G), a 12-week indicated two-component intervention aimed at improving the affective quality of the teacher-child relationship and teacher behaviour management. In a sample of 175 preschool boys showing signs of externalizing behaviour (M age  = 4 years, 9 months, SD age  = 7 months) and their teachers, we investigated P2G effects on academic engagement as well as on language achievement. Academic engagement was rated by teachers at three occasions within one school year (T1 = pretest, T3 = post-test, and T2 = in-between intervention components). Language achievement was assessed by researchers at pre- and post-test, using a standardized test. Cross-lagged path analyses revealed a direct intervention effect of P2G on academic engagement at Time 2. In addition, a significant indirect intervention effect was found on academic engagement at Time 3 through academic engagement at Time 2. Finally, academic engagement at Time 2 was found to predict language achievement at post-test. A marginally significant indirect intervention effect was found on language achievement at Time 3, through academic engagement at Time 2. This intervention study suggests that teacher-child interactions predict academic engagement over time, which in turn improves language achievement among preschool boys at risk of externalizing behaviour. © 2017 The British Psychological Society.

Collaboration between Mathematics Facilitators and Preschool Teachers Using the Innovative "Senso-Math" Preschool Program

Science.gov (United States)

Hassidov, Dina; Ilany, Bat-Sheva

2018-01-01

This article presents a mixed-method study of the innovative "Senso-Math" preschool program and the reactions of both the facilitators, who underwent a special training program, and the preschool teachers in whose classes the program was implemented. The goal of the program is to enhance mathematical development in preschool children…

Reciprocity and Ethical Tuberculosis Treatment and Control.

Science.gov (United States)

Silva, Diego S; Dawson, Angus; Upshur, Ross E G

2016-03-01

This paper explores the notion of reciprocity in the context of active pulmonary and laryngeal tuberculosis (TB) treatment and related control policies and practices. We seek to do three things: First, we sketch the background to contemporary global TB care and suggest that poverty is a key feature when considering the treatment of TB patients. We use two examples from TB care to explore the role of reciprocity: isolation and the use of novel TB drugs. Second, we explore alternative means of justifying the use of reciprocity through appeal to different moral and political theoretical traditions (i.e., virtue ethics, deontology, and consequentialism). We suggest that each theory can be used to provide reasons to take reciprocity seriously as an independent moral concept, despite any other differences. Third, we explore general meanings and uses of the concept of reciprocity, with the primary intention of demonstrating that it cannot be simply reduced to other more frequently invoked moral concepts such as beneficence or justice. We argue that reciprocity can function as a mid-level principle in public health, and generally, captures a core social obligation arising once an individual or group is burdened as a result of acting for the benefit of others (even if they derive a benefit themselves). We conclude that while more needs to be explored in relation to the theoretical justification and application of reciprocity, sufficient arguments can be made for it to be taken more seriously as a key principle within public health ethics and bioethics more generally.

Reciprocation of perceived organizational support.

Science.gov (United States)

Eisenberger, R; Armeli, S; Rexwinkel, B; Lynch, P D; Rhoades, L

2001-02-01

Four hundred thirteen postal employees were surveyed to investigate reciprocation's role in the relationships of perceived organizational support (POS) with employees' affective organizational commitment and job performance. The authors found that (a) POS was positively related to employees' felt obligation to care about the organization's welfare and to help the organization reach its objectives; (b) felt obligation mediated the associations of POS with affective commitment, organizational spontaneity, and in-role performance; and (c) the relationship between POS and felt obligation increased with employees' acceptance of the reciprocity norm as applied to work organizations. Positive mood also mediated the relationships of POS with affective commitment and organizational spontaneity. The pattern of findings is consistent with organizational support theory's assumption that POS strengthens affective commitment and performance by a reciprocation process.

Symmetry-based reciprocity: evolutionary constraints on a proximate mechanism.

Science.gov (United States)

Campennì, Marco; Schino, Gabriele

2016-01-01

Background. While the evolution of reciprocal cooperation has attracted an enormous attention, the proximate mechanisms underlying the ability of animals to cooperate reciprocally are comparatively neglected. Symmetry-based reciprocity is a hypothetical proximate mechanism that has been suggested to be widespread among cognitively unsophisticated animals. Methods. We developed two agent-based models of symmetry-based reciprocity (one relying on an arbitrary tag and the other on interindividual proximity) and tested their ability both to reproduce significant emergent features of cooperation in group living animals and to promote the evolution of cooperation. Results. Populations formed by agents adopting symmetry-based reciprocity showed differentiated "social relationships" and a positive correlation between cooperation given and received: two common aspects of animal cooperation. However, when reproduction and selection across multiple generations were added to the models, agents adopting symmetry-based reciprocity were outcompeted by selfish agents that never cooperated. Discussion. In order to evolve, hypothetical proximate mechanisms must be able to stand competition from alternative strategies. While the results of our simulations require confirmation using analytical methods, we provisionally suggest symmetry-based reciprocity is to be abandoned as a possible proximate mechanism underlying the ability of animals to reciprocate cooperative interactions.

Familial Reciprocity and Subjective Well-Being in Ghana

Science.gov (United States)

Tsai, Ming-Chang; Dzorgbo, Dan-Bright S.

2012-01-01

The authors investigated variations in reciprocity and the impact of reciprocity on well-being in a West African society. They hypothesized that household size and income diversity encourage reciprocity, which in turn enhances subjective well-being. In empirical testing of these hypotheses the authors used the data of the Core Welfare Indicators…

Transition between Swedish Preschool and Preschool Class: A Question about Interweaving Care and Knowledge

Science.gov (United States)

Alatalo, Tarja; Meier, Joanna; Frank, Elisabeth

2016-01-01

This study highlights teachers' experiences with transition from Swedish preschool to preschool class, i.e. from the daycare centre to the formal school. One assumption was that transition activities, to favour continuity in the long-term, need to focus on children's learning within the target areas that the policy documents specify for preschool.…

Short-Term Reciprocity in Late Parent-Child Relationships

Science.gov (United States)

Leopold, Thomas; Raab, Marcel

2011-01-01

Long-term concepts of parent-child reciprocity assume that the amount of support given and received is only balanced in a generalized fashion over the life course. We argue that reciprocity in parent-child relationships also operates in the short term. Our analysis of short-term reciprocity focuses on concurrent exchange in its main upward and…

Longitudinal, reciprocal effects of social skills and achievement from kindergarten to eighth grade.

Science.gov (United States)

Caemmerer, Jacqueline M; Keith, Timothy Z

2015-08-01

Previous research suggests that students' social skills and achievement are interrelated, and some findings support bi-directional effects between the two constructs. The purpose of this research study was to estimate the possible longitudinal and reciprocal effects of social skills and achievement for kindergarten through eighth grade students. Data from the Early Childhood Longitudinal Study program were analyzed; teachers' ratings of students' social skills and students' standardized math and reading achievement performance were collected 4 and 5 times, respectively. Latent variable structural equation modeling was used to test a panel model of reciprocal, longitudinal effects of social skills and achievement. The results suggest that the effects of students' social skills and achievement are bi-directional, but the effects of students' achievement on their later social skills are stronger than the effects of social skills on achievement. The significant effects of students' social skills on their later achievement are mostly indirect. These findings suggest that the future social skills of students who struggle academically may be of particular concern to educators, and intervention and prevention efforts aimed to address both social and achievement skills may help remediate the other skill in the future. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Reciprocity theory of homogeneous reactions

Science.gov (United States)

Agbormbai, Adolf A.

1990-03-01

The reciprocity formalism is applied to the homogeneous gaseous reactions in which the structure of the participating molecules changes upon collision with one another, resulting in a change in the composition of the gas. The approach is applied to various classes of dissociation, recombination, rearrangement, ionizing, and photochemical reactions. It is shown that for the principle of reciprocity to be satisfied it is necessary that all chemical reactions exist in complementary pairs which consist of the forward and backward reactions. The backward reaction may be described by either the reverse or inverse process. The forward and backward processes must satisfy the same reciprocity equation. Because the number of dynamical variables is usually unbalanced on both sides of a chemical equation, it is necessary that this balance be established by including as many of the dynamical variables as needed before the reciprocity equation can be formulated. Statistical transformation models of the reactions are formulated. The models are classified under the titles free exchange, restricted exchange and simplified restricted exchange. The special equations for the forward and backward processes are obtained. The models are consistent with the H theorem and Le Chatelier's principle. The models are also formulated in the context of the direct simulation Monte Carlo method.

Nature in Preschool

DEFF Research Database (Denmark)

Husted, Mia; Frøkjær, Thorleif

‘Nature and nature phenomena’ has formed a specific curriculum theme in Danish preschool since early childhood curriculum was prescribed by law in 2004. However, recent evaluations show that the implementation of an early childhood curriculum has not produced an increased pedagogical focus...... on ‘nature and nature phenomena’ in preschools (EVA 2012). This finding, along with an increased political interest in goals and measurable outcome of early childhood curriculum (Broström 2012), will be the starting point in our ambition to carry out a more thorough qualitative investigation into links...... between preschool teachers’ understanding and interest in teaching nature and the rather poor evaluation....

Preschool teachers’ reasoning about interactive whiteboard embedded in Swedish preschools

Directory of Open Access Journals (Sweden)

Maryam Bourbour

2014-01-01

Full Text Available This paper aims to investigate the ways in which teachers enact the interactive whiteboard (IWB in Swedish preschools in relation to preschool children’s mathematical learning. Data collected from interviews with four preschool teachers have provided the opportunity to consider the potential of IWB to facilitate a creative approach to young children’s mathematic education. The findings suggest that IWB use in preschool is mostly viewed as “Space for children to involve in problem-solving situations”, “Supporting collaborative learning and mutual negotiation”, “Goal-oriented mathematics learning facilitated by IWB” and “Retaining children’s interest in learning activities”. This study also highlights the importance of teachers’ technological knowledge and skills in mediating the interaction and facilitating the use of IWB in preschool pedagogical practices. Normal 0 21 false false false SV JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Normal tabell"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Cambria","serif"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;}

Evaluation of reciprocal cross populations for spike-related traits in early consecutive generations of bread wheat (Triticum aestivum L.

Directory of Open Access Journals (Sweden)

Kutlu Imren

2017-01-01

Full Text Available Breeding effort on increasing grain yield of wheat will incessantly continue because it is indispensable product. Obtaining the genetic information such as genotypic variation, heritability, genetic advance is the fundamental components of these studies. It is important that the maternal effects are put forward throughout successive generations because of genotypic and/or environmental effects as far as variation. This research was conducted to investigate changes of reciprocal crosses throughout successive generations and determine selection criteria for high yield in early generations. For this purpose, the populations were analyzed with regard to genotypic and phenotypic variation coefficient, heritability, genetic advance and Unweighted Pair Group Method (UPGMA cluster analysis for real crosses, reciprocals and all genotypes separately. According to the results, heritability and genetic advance values of traits investigated were highly varied throughout successive generations among real crosses, reciprocals and all genotypes. This finding indicated that non-additive gen effects or epitasis played a role in inheritance of all traits. Dissimilarity of crosses than their reciprocals indicated variation of successive generation. Dissimilarity value of each parent differed as generation progresses according to combination created. This condition suggested that there were maternal effects in this population throughout successive generations. Grain weight per spike, spike harvest index and spike density had high direct and indirect effects on the grain yield at all of three generations, it proved that these traits can be a selection criterion for early generations. Sana was the best parent and ‘Bezostaja x Krasunia’ and ‘Krasunia x Pehlivan’ were best performance in most of traits at all generations.

Pre-School Education in Europe.

Science.gov (United States)

Blackstone, Tessa

The extent and nature of preschool education in Europe is discussed, with reference to England and Wales, France, the Netherlands, Norway and Sweden. Reports on preschool education in these countries give examples of both an early and a late start to compulsory education, very extensive and very limited preschool provision, and the effects of…

Physical Activity in Preschool Children: Comparison between Montessori and Traditional Preschools

Science.gov (United States)

Pate, Russell R.; O'Neill, Jennifer R.; Byun, Wonwoo; McIver, Kerry L.; Dowda, Marsha; Brown, William H.

2014-01-01

Background: Little is known about the influence of Montessori methods on children's physical activity (PA). This cross-sectional study compared PA of children attending Montessori and traditional preschools. Methods: We enrolled 301 children in 9 Montessori and 8 traditional preschools in Columbia, South Carolina. PA was measured by accelerometry…

Science Education in Preschool: How to Assimilate the Reggio Emilia Pedagogy in a Turkish Preschool

Science.gov (United States)

Inan, Hatice Zeynep

2009-01-01

This commentary manuscript, which was part of a larger research project, aimed to show how teachers can help preschoolers construct their knowledge of science and meet preschool science standards successfully in a Reggio Emilia approach. The demonstrations for preschool teachers are summarized as follows: be inspired by the Reggio Emilia approach;…

Study of image reconstruction for terahertz indirect holography with quasi-optics receiver.

Science.gov (United States)

Gao, Xiang; Li, Chao; Fang, Guangyou

2013-06-01

In this paper, an indirect holographic image reconstruction algorithm was studied for terahertz imaging with a quasi-optics receiver. Based on the combination of the reciprocity principle and modified quasi-optics theory, analytical expressions of the received spatial power distribution and its spectrum are obtained for the interference pattern of target wave and reference wave. These results clearly give the quantitative relationship between imaging quality and the parameters of a Gaussian beam, which provides a good criterion for terahertz quasi-optics transceivers design in terahertz off-axis holographic imagers. To validate the effectiveness of the proposed analysis method, some imaging results with a 0.3 THz prototype system are shown based on electromagnetic simulation.

Static and kinematic formulation of planar reciprocal assemblies

DEFF Research Database (Denmark)

Parigi, Dario; Sassone, Mario; Kirkegaard, Poul Henning

2014-01-01

Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed extending the theory of pin-jointed assemblies....... This formulation is used to evaluate the static and kinematic determinacy of reciprocal assemblies from the properties of their equilibrium and kinematic matrices...

Detailed balance and reciprocity in solar cells

Energy Technology Data Exchange (ETDEWEB)

Kirchartz, Thomas; Rau, Uwe [IEF5-Photovoltaik, Forschungszentrum Juelich, 52425 Juelich (Germany)

2008-12-15

The limiting efficiency of photovoltaic devices follows from the detailed balance of absorption and emission of a diode according to the Shockley-Queisser theory. However, the principle of detailed balance has more implications for the understanding of photovoltaic devices than only defining the efficiency limit. We show how reciprocity relations between carrier collection and dark carrier injection, between electroluminescence emission and photovoltaic quantum efficiency and between open circuit voltage and light emitting diode quantum efficiency all follow from the principle of detailed balance. We also discuss the validity range of the Shockley-Queisser limit and the reciprocity relations. Discussing the validity of the reciprocity relations helps to deepen the understanding of photovoltaic devices and allows us to identify interrelationships between the superposition principle, the diode ideality and the reciprocity relations. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

[Formula: see text]Associations among parent-child relationships and cognitive and language outcomes in a clinical sample of preschool children.

Science.gov (United States)

Leiser, Kara; Heffelfinger, Amy; Kaugars, Astrida

2017-02-01

To examine associations among parent-child relationship characteristics and child cognitive and language outcomes. Preschool children (n = 72) with early neurological insult completed assessments of cognitive and language functioning and participated in a parent-child semi-structured interaction. Quality of the parent-child relationship accounted for a significant amount of unique variance (12%) in predicting children's overall cognitive and language functioning. Impact of neurological insult was a significant predictor. Caregiver-child interactions that are harmonious and reciprocal as evidenced by affective and/or verbal exchanges support children's cognitive and language development. Observations of interactions can guide providers in facilitating child- and family-centered interventions.

Sleep, Affect, and Social Competence from Preschool to Preadolescence: Distinct Pathways to Emotional and Social Adjustment for Boys and for Girls

Directory of Open Access Journals (Sweden)

Joan E. Foley

2017-05-01

Full Text Available Using a normative sample of 1,057 children studied across 4 waves over 6 years with multiple informants, we investigated transactional relations for sleep problems, anxious-depressed symptoms, and social functioning from preschool to preadolescence, assessing cumulative effects on children's emotional and social adjustment. To examine sex differences in the developmental processes, we conducted separate analyses for boys and girls. For both boys and girls, longitudinal cross-lagged panel analyses showed that preschool sleep problems directly predicted anxious-depressed symptoms 2 years later; indirect effects continued into preadolescence. For girls, early and later sleep problems directly or indirectly predicted a wide variety of preadolescent emotional and social adjustment domains (e.g., depressive symptoms, school competence, emotion regulation, risk-taking behaviors. For boys, social competence played a more important role than sleep problems in predicting preadolescent adjustment. Among the first set of findings that demonstrate longitudinal relations between sleep problems and social functioning in middle childhood and preadolescence, these results support Dahl's and Walker's neurological models of sleep and emotional functioning. We discuss these findings in light of relations between sleep and affect during pre-pubertal development and discuss differential findings for boys and girls.

Histological evaluation of the cleaning effectiveness of two reciprocating single-file systems in severely curved root canals: Reciproc versus WaveOne.

Science.gov (United States)

Carvalho, Maira de Souza; Junior, Emílio Carlos Sponchiado; Bitencourt Garrido, Angela Delfina; Roberti Garcia, Lucas da Fonseca; Franco Marques, André Augusto

2015-01-01

The aim of this study was to evaluate the cleaning effectiveness achieved with two reciprocating single-file systems in severely curved root canals: Reciproc and WaveOne. Twenty-five mesial roots of mandibular molars were randomly separated into two groups, according to the instrumentation system used. The negative control group consisted of five specimens that were not instrumented. The mesial canals (buccal and lingual) in Reciproc Group were instrumented with file R25 and the WaveOne group with the Primary file. The samples were submitted to histological processing and analyzed under a digital microscope. The WaveOne group presented a larger amount of debris than the Reciproc Group, however, without statistically significant difference (P > 0.05). A larger amount of debris in the control group was observed, with statistically significant difference to Reciproc and WaveOne groups (P file instrumentation systems presented similar effectiveness for root canal cleaning.

Exposure to Interpersonal Violence and Socioemotional Adjustment in Economically Disadvantaged Preschoolers

Science.gov (United States)

Bush, Hillary H.; Eisenhower, Abbey

2014-01-01

Focusing specifically on the experiences of economically disadvantaged preschoolers, the relations between interpersonal violence exposure, behavior problems, and social skills were examined in both the home and school settings. In this racially and ethnically diverse sample of preschoolers from poor, urban households (N = 64; 3-6 years old; 56% female), many children (33%) had been exposed to at least one type of interpersonal violence, and even more (70%) had been exposed to any type of potentially traumatic event (PTE). Although exposure to interpersonal violence was not directly associated with parent- or teacher-reported behavior problems or social skills, a significant interaction effect was observed between exposure to interpersonal violence and teacher-reported internalizing problems in predicting teacher-reported social skills; specifically, for children with the highest levels of internalizing problems, a positive relation between interpersonal violence exposure and social skills was observed. This indirect effect was observed only in the school setting, whereas children in this high-risk sample appeared to demonstrate resilience in the home setting. Given these high rates of exposure, additional, clinically-relevant research is needed to inform interventions for this vulnerable population. PMID:25175528

Information seeking and reciprocity: A transformational analysis

NARCIS (Netherlands)

Gallucci, M.; Perugini, M.

2003-01-01

The motivation to reciprocate is analyzed within the framework of interdependence theory, with focus on the process of transformation of situations. A model of transformation is presented for the motivation to reciprocate and hypotheses regarding allocation behavior and information seeking are

Bah humbug: Unexpected Christmas cards and the reciprocity norm.

Science.gov (United States)

Meier, Brian P

2016-01-01

The reciprocity norm refers to the expectation that people will help those who helped them. A well-known study revealed that the norm is strong with Christmas cards, with 20% of people reciprocating a Christmas card received from a stranger. I attempted to conceptually replicate and extend this effect. In Study 1, 755 participants received a Christmas card supposedly from a more- versus less-similar stranger. The reciprocation rate was unexpectedly low (2%), which did not allow for a test of a similarity effect. Two potential reasons for this low rate were examined in Study 2 in which 494 participants reported their likelihood of reciprocating a Christmas card from a stranger as well as their felt suspicions/threat about the card and their frequency of e-mail use. Reciprocation likelihood was negatively correlated with perceived threat/suspicion and e-mail use. It appears that reciprocating a gift from a stranger in offline settings may be less likely than expected.

Nonreciprocal and Reciprocal Dating Violence and Injury Occurrence among Urban Youth

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Swahn, Monica H

2010-08-01

Full Text Available Objective: Dating violence is a significant health problem among youth that leads to adverse health outcomes, including injuries. Reciprocal violence (perpetrated by both partners is associated with increased injury in adults, but very little is known about the prevalence and context for reciprocal violence, as well as injury rates, among youth. We sought to determine the prevalence and scope of reciprocal dating violence and injury occurrence among urban youth in a high-risk community. Methods: Analyses were based on data from the Youth Violence Survey, conducted in 2004, and administered to over 80% of public school students in grades 7, 9, 11, and 12 (N=4,131 in a high-risk, urban school district. The current analyses were restricted to those who reported dating in the past year and who also reported any dating violence (n=1,158. Dating violence was categorized as reciprocal (the participant reported both violence perpetration and victimization and non-reciprocal (the participant report either violence perpetration or victimization, but not both. Results: Dating violence reciprocity varied by sex. Girls who reported any dating violence were more likely to report reciprocal dating violence (50.4% than were boys (38.9%. However, reciprocity did not vary by race/ethnicity or grade level. Reciprocal dating violence was more common among participants who reported more frequent violence experiences. Reciprocal violence was also associated with greater injury occurrences relative to non-reciprocal relationships (10.1% versus 1.2%. Conclusion: Reciprocal dating violence is common among adolescents and leads more often to injury outcomes. In particular, relationships in which boys report reciprocal violence against their partner appear to lead to more frequent injury occurrences. These findings underscore the importance of addressing dating violence and factors that increase risk for reciprocal violence and therefore exacerbate injury occurrence

Quality in preschool in a cultural context

DEFF Research Database (Denmark)

Kragh-Müller, Grethe; Ringsmose, Charlotte

What is educational quality i preschools? How can it be evaluated/measured. How can educational quality be developped in everyday life in preschools?......What is educational quality i preschools? How can it be evaluated/measured. How can educational quality be developped in everyday life in preschools?...

A 1.5 GFLOPS Reciprocal Unit for Computer Graphics

DEFF Research Database (Denmark)

Nannarelli, Alberto; Rasmussen, Morten Sleth; Stuart, Matthias Bo

2006-01-01

The reciprocal operation 1/d is a frequent operation performed in graphics processors (GPUs). In this work, we present the design of a radix-16 reciprocal unit based on the algorithm combining the traditional digit-by-digit algorithm and the approximation of the reciprocal by one Newton-Raphson i...

Reciprocity in electron diffraction

International Nuclear Information System (INIS)

Gunning, J.; Goodman, P.

1991-01-01

The symmetry of reciprocity is reviewed in the context of relativistic quantum mechanics with the specific aim of relating to P-C-T invariances. From this investigation global time reversal is found to be sufficient condition for reciprocity to hold in scattering from a vector potential. Elastic scattering is assumed. The paper also deals exclusively with the scattering of a charged particle by an electromagnetic field. The present proof is free from assumptions of small angle scattering and from restrictions on z-dependent terms in the scattering equation, and by avoiding S-matrix theory is thought to be accessible to undergraduate teaching. 9 refs., 1 tab., 1 fig

Some properties of generalized self-reciprocal polynomials over finite fields

Directory of Open Access Journals (Sweden)

Ryul Kim

2014-07-01

Full Text Available Numerous results on self-reciprocal polynomials over finite fields have been studied. In this paper we generalize some of these to a-self reciprocal polynomials defined in [4]. We consider some properties of the divisibility of a-reciprocal polynomials and characterize the parity of the number of irreducible factors for a-self reciprocal polynomials over finite fields of odd characteristic.

Preschool teacher's view on learning in preschool in Sweden and Denmark

DEFF Research Database (Denmark)

Broström professor m.so., Stig; Frøkjær, Thorleif; Johansson, Inge

2014-01-01

The aim of this study was to examine how preschool teachers in Sweden and Denmark perceive children’s learning in preschool. The study aimed to answer the following questions: What is ‘learning’? How do children learn? What are the best conditions for children’s learning? What is the role of part...

Reciprocal relations for transmission coefficients - Theory and application

Science.gov (United States)

Qu, Jianmin; Achenbach, Jan D.; Roberts, Ronald A.

1989-01-01

The authors present a rigorous proof of certain intuitively plausible reciprocal relations for time harmonic plane-wave transmission and reflection at the interface between a fluid and an anisotropic elastic solid. Precise forms of the reciprocity relations for the transmission coefficients and for the transmitted energy fluxes are derived, based on the reciprocity theorem of elastodynamics. It is shown that the reciprocity relations can be used in conjunction with measured values of peak amplitudes for transmission through a slab of the solid (water-solid-water) to obtain the water-solid coefficients. Experiments were performed for a slab of a unidirectional fiber-reinforced composite. Good agreement of the experimentally measured transmission coefficients with theoretical values was obtained.

Training the Hippocampus and Amygdala of Preschool Children by Means of Priming Tasks: Should Parents Rather Focus on Learning of Facts than Reading Fairytales?

Science.gov (United States)

Pretorius, E.; Naude, H.; Pretorius, U.

2005-01-01

One of the main functions of the human brain is memory, and this forms the basis of learning and is the cornerstone of IQ. One of the important aims for both parents and educators of preschool children is to improve or develop the child's self-application of intelligence in the classroom, which indirectly involves memory capability development.…

Acoustic reciprocity: An extension to spherical harmonics domain.

Science.gov (United States)

Samarasinghe, Prasanga; Abhayapala, Thushara D; Kellermann, Walter

2017-10-01

Acoustic reciprocity is a fundamental property of acoustic wavefields that is commonly used to simplify the measurement process of many practical applications. Traditionally, the reciprocity theorem is defined between a monopole point source and a point receiver. Intuitively, it must apply to more complex transducers than monopoles. In this paper, the authors formulate the acoustic reciprocity theory in the spherical harmonics domain for directional sources and directional receivers with higher order directivity patterns.

Structural optimization of free-form reciprocal structures

DEFF Research Database (Denmark)

Parigi, Dario

2014-01-01

This paper presents an optimization algorithm for the design of structurally efficient free-form reciprocal structures. Because of the geometric complexity of reciprocal structures, only a few structural studies have been carried out so far, and we have a limited knowledge of the relation between...

Loneliness, exchange orientation, and reciprocity in friendships

NARCIS (Netherlands)

Buunk, Abraham (Bram); Prins, K.S.

Guided by equity theory this study among 185 Dutch students explored the effects of exchange orientation and reciprocity in the relationship with the best friend upon loneliness. Reciprocity was in general more common in this relationship than feeling advantaged or deprived. The association between

24 CFR 3282.11 - Preemption and reciprocity.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Preemption and reciprocity. 3282.11 Section 3282.11 Housing and Urban Development Regulations Relating to Housing and Urban Development... and reciprocity. (a) No State manufactured home standard regarding manufactured home construction and...

Born's reciprocity principle in stochastic phase space

International Nuclear Information System (INIS)

Prugovecki, E.

1981-01-01

It is shown that the application of Born's reciprocity principle to relativistic quantum mechanics in stochastic phase space (by the requirement that the proper wave functions of extended particles satisfy the Born-Lande as well as the Klein-Gordon equation) leads to the unique determination of these functions for any given value of their rms radius. The resulting particle propagators display not only Lorentz but also reciprocal invariance. This feature remains true even in the case of mass-zero particles, such as photons, when their localization is achieved by means of extended test particles whose proper wave functions obey the reciprocity principle. (author)

Reading use in preschool

OpenAIRE

Laísa Cristina dos Santos Guilherme; Rodrigo Ferreira Daverni

2016-01-01

Abstract: Reading in preschool is a time of awakening the taste and pleasure in reading, it is also a source of reflection, discovery and learn to listen. It is then necessary that the contact with the reading start from pre-school, with a variety of texts and the teacher also has the habit of reading in their daily lives. Therefore, this study aimed to investigate the benefits of daily reading in the classroom pre-school life of a student, which the characteristics of a player and teacher re...

Motivations and Barriers in Promoting Preschool Education

Science.gov (United States)

Küçükturan, A. Güler; Akbaba Altun, Sadegül

2017-01-01

This study is designed to explore the reasons for sending and not sending preschool age children to preschools at an early age by exploring the motivations for and barriers towards promoting preschool education in Turkey. It aimed to determine various stakeholders' perceptions, attitudes, and knowledge related to preschool education in order to…

Reciprocal Tutoring: Design with Cognitive Load Sharing

Science.gov (United States)

Chou, Chih-Yueh; Chan, Tak-Wai

2016-01-01

"Reciprocal tutoring," as reported in "Exploring the design of computer supports for reciprocal tutoring" (Chan and Chou 1997), has extended the meaning and scope of "intelligent tutoring" originally implemented in stand alone computers. This research is a follow-up to our studies on a "learning companion…

Drift stabilizer for reciprocating free-piston devices

Science.gov (United States)

Ward, William C.; Corey, John A.; Swift, Gregory W.

2003-05-20

A free-piston device has a stabilized piston drift. A piston having a frequency of reciprocation over a stroke length and with first and second sides facing first and second variable volumes, respectively, for containing a working fluid defining an acoustic wavelength at the frequency of reciprocation. A bypass tube waveguide connects the first and second variable volumes at all times during reciprocation of the piston. The waveguide has a relatively low impedance for steady flow and a relatively high impedance for oscillating flow at the frequency of reciprocation of the piston, so that steady flow returns fluid leakage from about the piston between the first and second volumes while oscillating flow is not diverted through the waveguide. Thus, net leakage about the piston is returned during each stroke of the piston while oscillating leakage is not allowed and pressure buildup on either the first or second side of the piston is avoided to provide a stable piston location.

Intrinsic rippling enhances static non-reciprocity in a graphene metamaterial.

Science.gov (United States)

Ho, Duc Tam; Park, Harold S; Kim, Sung Youb

2018-01-18

In mechanical systems, Maxwell-Betti reciprocity means that the displacement at point B in response to a force at point A is the same as the displacement at point A in response to the same force applied at point B. Because the notion of reciprocity is general, fundamental, and is operant for other physical systems like electromagnetics, acoustics, and optics, there is significant interest in understanding systems that are not reciprocal, or exhibit non-reciprocity. However, most studies on non-reciprocity have occurred in bulk-scale structures for dynamic problems involving time reversal symmetry. As a result, little is known about the mechanisms governing static non-reciprocal responses, particularly in atomically-thin two-dimensional materials like graphene. Here, we use classical atomistic simulations to demonstrate that out-of-plane ripples, which are intrinsic to graphene, enable significant, multiple orders of magnitude enhancements in the statically non-reciprocal response of graphene metamaterials. Specifically, we find that a striking interplay between the ripples and the stress fields that are induced in the metamaterials due to their geometry impacts the displacements that are transmitted by the metamaterial, thus leading to a significantly enhanced static non-reciprocal response. This study thus demonstrates the potential of two-dimensional mechanical metamaterials for symmetry-breaking applications.

Mortality salience increases personal relevance of the norm of reciprocity.

Science.gov (United States)

Schindler, Simon; Reinhard, Marc-André; Stahlberg, Dagmar

2012-10-01

Research on terror management theory found evidence that people under mortality salience strive to live up to salient cultural norms and values, like egalitarianism, pacifism, or helpfulness. A basic, strongly internalized norm in most human societies is the norm of reciprocity: people should support those who supported them (i.e., positive reciprocity), and people should injure those who injured them (i.e., negative reciprocity), respectively. In an experiment (N = 98; 47 women, 51 men), mortality salience overall significantly increased personal relevance of the norm of reciprocity (M = 4.45, SD = 0.65) compared to a control condition (M = 4.19, SD = 0.59). Specifically, under mortality salience there was higher motivation to punish those who treated them unfavourably (negative norm of reciprocity). Unexpectedly, relevance of the norm of positive reciprocity remained unaffected by mortality salience. Implications and limitations are discussed.

Nutritional practices in full-day-care pre-schools.

LENUS (Irish Health Repository)

Jennings, A

2011-06-01

Full-day-care pre-schools contribute significantly to the nutritional intake and acquisition of dietary habits of the pre-school child. The present study investigated nutritional practices in full-day-care pre-schools in Dublin, Ireland, aiming to determine the nutritional support that pre-school managers deem necessary, thereby facilitating the amelioration of existing pre-school nutritional training and practices.

Design and Fabrication of a Free-Form Reciprocal Roof

DEFF Research Database (Denmark)

Parigi, Dario

2015-01-01

The paper presents the framework and the design and construction process of a freeform reciprocal pavilion realized during a one-week long workshop with the students of the 1st semester of the Master of Science in Architecture and Design, fall 2014, at Aalborg University. The workshop didactic...... of relations between design parameters and a wide array of measurable performances. Due to the reciprocal structures geometric complexity, the shape generation process is handled using the Reciprocalizer, a software tool developed by the author that embeds in a computational environment the constructional...... logic of reciprocal structures. It enables to engage in real time in iterative processes that allows unfolding the geometric complexity and turn it into a source of inspiration for expanding the design space and triggering the development of unique, adapted and integrated design solutions. Reciprocal...

Defining Nature-Based Preschools

Science.gov (United States)

Larimore, Rachel

2016-01-01

Nature-based early childhood education. Nature-based preschool. Nature preschool. Forest kindergarten. Nature kindergarten. Waldkindergarten. Forest school. These are a few of the program terms currently being discussed among early childhood environmental education professionals in the United States. Why is there so much discussion about the names…

Education, Gift and Reciprocity: A Preliminary Discussion

Science.gov (United States)

Sabourin, Eric

2013-01-01

This paper analyzes the importance and role of the reciprocity relationship in education. It presents a review on the mobilization of the principle of reciprocity--in the anthropological but also sociological and economic senses--in educational processes, especially in adult education. The study is divided into three parts. The first part analyzes…

The Arts in Turkish Preschool Education

Science.gov (United States)

Acer, Dilek

2015-01-01

One of the most important factors determining a nation's level of development in the modern world is preschool education. When preschool education is perceived as an entity that affects every aspect of childhood development, this fact is undeniable. Several aspects of preschool education, including art education, play a significant role in a…

Working dogs cooperate among one another by generalised reciprocity.

Science.gov (United States)

Gfrerer, Nastassja; Taborsky, Michael

2017-03-06

Cooperation by generalised reciprocity implies that individuals apply the decision rule "help anyone if helped by someone". This mechanism has been shown to generate evolutionarily stable levels of cooperation, but as yet it is unclear how widely this cooperation mechanism is applied among animals. Dogs (Canis familiaris) are highly social animals with considerable cognitive potential and the ability to differentiate between individual social partners. But although dogs can solve complex problems, they may use simple rules for behavioural decisions. Here we show that dogs trained in an instrumental cooperative task to provide food to a social partner help conspecifics more often after receiving help from a dog before. Remarkably, in so doing they show no distinction between partners that had helped them before and completely unfamiliar conspecifics. Apparently, dogs use the simple decision rule characterizing generalised reciprocity, although they are probably capable of using the more complex decision rule of direct reciprocity: "help someone who has helped you". However, generalized reciprocity involves lower information processing costs and is therefore a cheaper cooperation strategy. Our results imply that generalised reciprocity might be applied more commonly than direct reciprocity also in other mutually cooperating animals.

The influence of the reciprocal hip joint link in the advanced reciprocating gait orthosis on standing performance in paraplegia

NARCIS (Netherlands)

Baardman, G.; IJzerman, Maarten Joost; Hermens, Hermanus J.; Veltink, Petrus H.; Boom, H.B.K.; Zilvold, G.; Zilvold, G.

1997-01-01

The effect of reciprocally linking the hip hinges of a hip-knee-ankle-foot orthosis on standing performance was studied in a comparative trial of the Advanced Reciprocating Gait Orthosis (ARGO) and an ARGO in which the Bowden cable was removed (A_GO). Six male subjects with spinal cord injury (SCI)

Reciprocity, social ties, and competition in markets for experience goods

DEFF Research Database (Denmark)

Huck, Steffen; Tyran, Jean-Robert

2007-01-01

a positive externality for non-reciprocal customers who would, in the absence of reciprocal types, face market breakdown. This efficiency-enhancing effect of reciprocity is boosted when there are social ties between consumers and competition between firms. The existence of social ties or competition alone...

The Role of Friendship Reciprocity in University Freshmen's Alcohol Consumption.

Science.gov (United States)

Giese, Helge; Stok, F Marijn; Renner, Britta

2017-07-01

The similarity of friends in the frequency and quantity of alcohol consumption is explored. During their first semester, 57 psychology freshmen indicated weekly drinking frequency and quantity and nominated the three peers of this group they liked most. These nominations were then used to derive the weekly alcohol consumption of friends that either did or did not reciprocate a nomination. Multilevel modeling of weekly variations showed that individuals' drinking frequency was similar to peers who reciprocated a friendship (b = 0.15, p = .001), but not to non-reciprocating peers (b = -0.01, p = .720). In contrast, weekly variation in quantity of individual students' drinking was similar to both reciprocating (b = 0.11, p = .018) and non-reciprocating peers' drinking (b = 0.10, p = .014). Yet across all weeks, quantity tended only to be similar to non-reciprocating peers (b = 0.49, p = .020). Freshmen might spend drinking time with peers who reciprocate a friendship, but are similar regarding the quantity of drinks consumed to all people they find interesting. Thus, alcohol consumption is used strategically for social purposes. This social purpose should also be acknowledged in alcohol-reduction interventions. © 2017 The International Association of Applied Psychology.

Negative reciprocity and retrenched pension rights

OpenAIRE

Montizaan, R.M.; Cörvers, F.; de Grip, A.; Dohmen, T.J.

2012-01-01

We document the importance of negatively reciprocal inclinations in labor relationships by showing that a retrenchment of pension rights, which is perceived as unfair, causes a larger reduction in job motivation the stronger workers' negatively reciprocal inclinations are. We exploit unique matched survey and administrative data on male employees in the public sector in the Netherlands and compare the job motivation of employees born in 1950, who faced a substantial retrenchment of their pens...

The extended reciprocity: Strong belief outperforms persistence.

Science.gov (United States)

Kurokawa, Shun

2017-05-21

The existence of cooperation is a mysterious phenomenon and demands explanation, and direct reciprocity is one key potential explanation for the evolution of cooperation. Direct reciprocity allows cooperation to evolve for cooperators who switch their behavior on the basis of information about the opponent's behavior. Here, relevant to direct reciprocity is information deficiency. When the opponent's last move is unknown, how should players behave? One possibility is to choose cooperation with some default probability without using any further information. In fact, our previous paper (Kurokawa, 2016a) examined this strategy. However, there might be beneficial information other than the opponent's last move. A subsequent study of ours (Kurokawa, 2017) examined the strategy which uses the own last move when the opponent's last move is unknown, and revealed that referring to the own move and trying to imitate it when information is absent is beneficial. Is there any other beneficial information else? How about strong belief (i.e., have infinite memory and believe that the opponent's behavior is unchanged)? Here, we examine the evolution of strategies with strong belief. Analyzing the repeated prisoner's dilemma game and using evolutionarily stable strategy (ESS) analysis against an invasion by unconditional defectors, we find the strategy with strong belief is more likely to evolve than the strategy which does not use information other than the opponent player's last move and more likely to evolve than the strategy which uses not only the opponent player's last move but also the own last move. Strong belief produces the extended reciprocity and facilitates the evolution of cooperation. Additionally, we consider the two strategies game between strategies with strong belief and any strategy, and we consider the four strategies game in which unconditional cooperators, unconditional defectors, pessimistic reciprocators with strong belief, and optimistic reciprocators with

Reciprocity relations in aerodynamics

Science.gov (United States)

Heaslet, Max A; Spreiter, John R

1953-01-01

Reverse flow theorems in aerodynamics are shown to be based on the same general concepts involved in many reciprocity theorems in the physical sciences. Reciprocal theorems for both steady and unsteady motion are found as a logical consequence of this approach. No restrictions on wing plan form or flight Mach number are made beyond those required in linearized compressible-flow analysis. A number of examples are listed, including general integral theorems for lifting, rolling, and pitching wings and for wings in nonuniform downwash fields. Correspondence is also established between the buildup of circulation with time of a wing starting impulsively from rest and the buildup of lift of the same wing moving in the reverse direction into a sharp-edged gust.

Realizing total reciprocity violation in the phase for photon scattering.

Science.gov (United States)

Deák, László; Bottyán, László; Fülöp, Tamás; Merkel, Dániel Géza; Nagy, Dénes Lajos; Sajti, Szilárd; Schulze, Kai Sven; Spiering, Hartmut; Uschmann, Ingo; Wille, Hans-Christian

2017-02-22

Reciprocity is when wave or quantum scattering satisfies a symmetry property, connecting a scattering process with the reversed one. While reciprocity involves the interchange of source and detector, it is fundamentally different from rotational invariance, and is a generalization of time reversal invariance, occurring in absorptive media as well. Due to its presence at diverse areas of physics, it admits a wide variety of applications. For polarization dependent scatterings, reciprocity is often violated, but violation in the phase of the scattering amplitude is much harder to experimentally observe than violation in magnitude. Enabled by the advantageous properties of nuclear resonance scattering of synchrotron radiation, we have measured maximal, i.e., 180-degree, reciprocity violation in the phase. For accessing phase information, we introduced a new version of stroboscopic detection. The scattering setting was devised based on a generalized reciprocity theorem that opens the way to construct new types of reciprocity related devices.

Crystallization features of ternary reversible reciprocal systems

International Nuclear Information System (INIS)

Tomashik, V.N.; Shcherbak, L.P.; Fejchuk, P.I.; Grytsiv, V.I.

2006-01-01

Some features of the primary crystallization of phases in ternary reversible reciprocal system are considered and discussed. The diagonal join CdTe-GeSe of the CdTe + GeSe = CdSe + GeTe ternary reciprocal system is studied to show that the features in primary and secondary heating and cooling curves in such systems under fully equilibrium conditions are not reproduced upon consecutive heating and cooling sessions, because of the existence of different amounts of the reagents and the reaction products in the mixture; the temperatures of each transformation lie in a range. Those who experimentally investigate other ternary and more complex reversible reciprocal systems should take this fact into account [ru

Reciprocity and its utilization in ultrasonic flow meters

Energy Technology Data Exchange (ETDEWEB)

Lunde, Per; Vestrheim, Magne; Boe, Reidar; Smoergrav, Skule; Abrahamsen, Atle K.

2005-07-01

In ultrasonic transit time flow meters for gas and liquid (USMs), the flow direction, the flow velocity and the sound velocity are estimated from the measured up- and downstream transit times. At no-flow conditions, the up- and downstream transit times of such meters should ideally be the same, or the difference should be negligible. This may not be the case unless special precautions are made. In order to reduce the possibility of the meter to detect a false flow at no-flow conditions, USMs are typically ''dry calibrated'' before being installed in the field. ''Dry calibration'' (which may be made in different ways), in general involves measurement of (a) the time delays due to electronics, cables and transducers, (b) the so called ''{delta}t-correction'' (for each acoustic path, also denoted ''zero flow offset factor''), and (c) geometrical parameters. Various {delta}t-correction approaches may be used by different manufacturers, but these are basically similar and have the same purpose: to reduce the false flow detection and improve the accuracy at low and no-flow conditions (''zero flow adjustment''), without significantly affecting the accuracy at the high velocity measurements. The AGA-9 report and the API MPMS Ch. 5.8 standard both prescribe need for ''zero flow verification test (zero test)'' or ''zeroing the meter'', for gas and liquid USMs, respectively. Advances in USM technology based on the electro acoustic reciprocity principle have provided methods for reduction or even neglect ion of the need for ''{delta} t-correction'' of USMs. That means, if the USM measurement system is reciprocal, and operated in a ''sufficiently reciprocal'' way, the ''{delta}t-correction'' may be negligibly small over the operational range of pressure and temperature, and

Correlation of Positive and Negative Reciprocity Fails to Confer an Evolutionary Advantage: Phase Transitions to Elementary Strategies

Directory of Open Access Journals (Sweden)

Attila Szolnoki

2013-11-01

Full Text Available Economic experiments reveal that humans value cooperation and fairness. Punishing unfair behavior is therefore common, and according to the theory of strong reciprocity, it is also directly related to rewarding cooperative behavior. However, empirical data fail to confirm that positive and negative reciprocity are correlated. Inspired by this disagreement, we determine whether the combined application of reward and punishment is evolutionarily advantageous. We study a spatial public goods game, where in addition to the three elementary strategies of defection, rewarding, and punishment, a fourth strategy that combines the latter two competes for space. We find rich dynamical behavior that gives rise to intricate phase diagrams where continuous and discontinuous phase transitions occur in succession. Indirect territorial competition, spontaneous emergence of cyclic dominance, as well as divergent fluctuations of oscillations that terminate in an absorbing phase are observed. Yet, despite the high complexity of solutions, the combined strategy can survive only in very narrow and unrealistic parameter regions. Elementary strategies, either in pure or mixed phases, are much more common and likely to prevail. Our results highlight the importance of patterns and structure in human cooperation, which should be considered in future experiments.

Correlation of Positive and Negative Reciprocity Fails to Confer an Evolutionary Advantage: Phase Transitions to Elementary Strategies

Science.gov (United States)

Szolnoki, Attila; Perc, Matjaž

2013-10-01

Economic experiments reveal that humans value cooperation and fairness. Punishing unfair behavior is therefore common, and according to the theory of strong reciprocity, it is also directly related to rewarding cooperative behavior. However, empirical data fail to confirm that positive and negative reciprocity are correlated. Inspired by this disagreement, we determine whether the combined application of reward and punishment is evolutionarily advantageous. We study a spatial public goods game, where in addition to the three elementary strategies of defection, rewarding, and punishment, a fourth strategy that combines the latter two competes for space. We find rich dynamical behavior that gives rise to intricate phase diagrams where continuous and discontinuous phase transitions occur in succession. Indirect territorial competition, spontaneous emergence of cyclic dominance, as well as divergent fluctuations of oscillations that terminate in an absorbing phase are observed. Yet, despite the high complexity of solutions, the combined strategy can survive only in very narrow and unrealistic parameter regions. Elementary strategies, either in pure or mixed phases, are much more common and likely to prevail. Our results highlight the importance of patterns and structure in human cooperation, which should be considered in future experiments.

Attitudes toward reciprocity systems for organ donation and allocation for transplantation.

Science.gov (United States)

Burkell, Jacquelyn A; Chandler, Jennifer A; Shemie, Sam D

2013-10-01

Many of those who support organ donation do not register to become organ donors. The use of reciprocity systems, under which some degree of priority is offered to registered donors who require an organ transplant, is one suggestion for increasing registration rates. This article uses a combination of survey and focus group methodologies to explore the reaction of Canadians to a reciprocity proposal. Our results suggest that the response is mixed. Participants are more convinced of the efficacy than they are of the fairness of a reciprocity system. Those more positive about donation (decided donors and those leaning toward donation) rate the system more positively. Although there is general endorsement of the notion that those who wish to receive should be prepared to give (the Golden Rule), this does not translate into universal support for a reciprocity system. In discussions of efficacy, decided donors focus on the positive impact of reciprocity, whereas undecided donors also reflect on the limits of reciprocity for promoting registration. The results demonstrate divided support for reciprocity systems in the Canadian context, with perceptions of efficacy at the cost of fairness. Further studies are warranted prior to considering a reciprocity system in Canada.

Reciprocal link for a coupled Camassa–Holm type equation

International Nuclear Information System (INIS)

Li, Nianhua; Zhang, Jinshun; Wu, Lihua

2016-01-01

Highlights: • We construct a reciprocal transformation for a coupled Camassa–Holm type equation proposed by Geng and Xue. • The transformed coupled Camassa–Holm type system is a reduction of the first negative flow in a modified Drinfeld–Sokolov III hierarchy. • The Lax pair and bi-Hamiltonian structure behaviors of the coupled Camassa–Holm type equation under the reciprocal transformation are analyzed. - Abstract: A coupled Camassa–Holm type equation is linked to the first negative flow in a modified Drinfeld–Sokolov III hierarchy by a transformation of reciprocal type. Meanwhile the Lax pair and bi-Hamiltonian structure behaviors of this coupled Camassa–Holm type equation under the reciprocal transformation are analyzed.

Relatedness decreases and reciprocity increases cooperation in Norway rats.

Science.gov (United States)

Schweinfurth, Manon K; Taborsky, Michael

2018-03-14

Kin selection and reciprocity are two mechanisms underlying the evolution of cooperation, but the relative importance of kinship and reciprocity for decisions to cooperate are yet unclear for most cases of cooperation. Here, we experimentally tested the relative importance of relatedness and received cooperation for decisions to help a conspecific in wild-type Norway rats ( Rattus norvegicus ). Test rats provided more food to non-kin than to siblings, and they generally donated more food to previously helpful social partners than to those that had refused help. The rats thus applied reciprocal cooperation rules irrespective of relatedness, highlighting the importance of reciprocal help for cooperative interactions among both related and unrelated conspecifics. © 2018 The Author(s).

Promoting preschool reading

OpenAIRE

Istenič, Vesna

2013-01-01

The thesis titled Promoting preschool reading consists of a theoretiral and an empirical part. In the theoretical part I wrote about reading, the importance of reading, types of reading, about reading motivation, promoting reading motivation, internal and external motivation, influence of reading motivation on the child's reading activity, reading and familial literacy, the role of adults in promotion reading literacy, reading to a child and promoting reading in pre-school years, where I ...

45 CFR 605.38 - Preschool and adult education.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 3 2010-10-01 2010-10-01 false Preschool and adult education. 605.38 Section 605... Preschool, Elementary, and Secondary Education § 605.38 Preschool and adult education. A recipient to which this subpart applies that provides preschool education or day care or adult education may not, on the...

Contextual Specificity in the Relationship between Maternal Autonomy Support and Children's Socio-emotional Development: A Longitudinal Study from Preschool to Preadolescence.

Science.gov (United States)

Matte-Gagné, Célia; Harvey, Brenda; Stack, Dale M; Serbin, Lisa A

2015-08-01

The benefits of an autonomy supportive environment have been established as a key component in children's development at various ages. Nonetheless, research examining the outcomes of early autonomy supportive environments has largely neglected socio-emotional development. The first objective of the present longitudinal study was to examine the socio-emotional outcomes associated with maternal autonomy support during the preschool period. Second, we explored the contextual specificity of the relationships between maternal autonomy support and children's later socio-emotional outcomes. Finally, we investigated the indirect effect of maternal autonomy support on children's later socio-emotional outcomes through earlier children's socio-emotional outcomes. Sixty-six mothers and their pre-school aged children (41 girls) were followed during preschool (Time 1), elementary school (Time 2) and preadolescence (Time 3). Maternal autonomy support (Time 1) was measured in two contexts (free-play and interference task) using observational coding. Furthermore, the children's internalizing and externalizing problems as well as their social competence were measured at Times 2 and 3. The results revealed the importance of maternal autonomy support during preschool for children's later socio-emotional development, especially during challenging contexts, and the mediating role of children's socio-emotional outcomes during elementary school in the link between maternal autonomy support during the preschool years and children's later socio-emotional outcomes during preadolescence. The results highlight the contextual specificity of the relationship between maternal autonomy support and children's later socio-emotional development and reveal one of the mechanisms through which the effect of early childhood parental autonomy support on children's later socio-emotional development is carried forward over time.

Static And Kinematic Formulation Of Planar Reciprocal Assemblies

DEFF Research Database (Denmark)

Parigi, Dario; Kirkegaard, Poul Henning

2013-01-01

Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed by extending the work on pin-jointed assemblies by Pe...

Reciprocity on Demand : Sharing and Exchanging Food in Northwestern Namibia.

Science.gov (United States)

Schnegg, Michael

2015-09-01

Two competing models concerning food transfers prominent in the anthropological literature conceptualize such transfers either as sharing or as exchange. Sharing is understood as situational transactions formed through demands and unconditional giving, whereas reciprocal exchange is understood in terms of networking and keeping score. I propose that the picture is more complicated than these classifications suggests. Drawing on data collected in Northwestern Namibia, I show that sharing and reciprocal exchange are dynamically interrelated in actual food transfers. As a local norm, people can demand food from anyone, and they are typically given food in response to a demand. However, in practice, food transfer networks emerge (N = 62) that are highly reciprocal and fit the exchange model much better. Although the sharing norm makes no restrictions on whom to ask, in practice people often turn to their neighbors. Interpersonal dynamics account for why some of those ties become strongly reciprocal and others do not. Under these circumstances, unconditional sharing, a norm that has been viewed as an alternative to exchange, can lead to reciprocity via reciprocity on demand.

Generalized Gribov-Lipatov Reciprocity and AdS/CFT

International Nuclear Information System (INIS)

Beccaria, M.; Macorini, G.; Forini, V.

2010-01-01

Planar □=4 SYM theory and QCD share the gluon sector, suggesting the investigation of Gribov-Lipatov reciprocity in the supersymmetric theory. Since the AdS/CFT correspondence links □=4 SYM and superstring dynamics on AdS 5 x S5, reciprocity is also expected to show up in the quantum corrected energies of certain classical string configurations dual to gauge theory twist-operators. We review recent results confirming this picture and revisiting the old idea of Gribov-Lipatov reciprocity as a modern theoretical tool useful for the study of open problems in AdS/CFT.

Research on networked manufacturing system for reciprocating pump industry

Science.gov (United States)

Wu, Yangdong; Qi, Guoning; Xie, Qingsheng; Lu, Yujun

2005-12-01

Networked manufacturing is a trend of reciprocating pump industry. According to the enterprises' requirement, the architecture of networked manufacturing system for reciprocating pump industry was proposed, which composed of infrastructure layer, system management layer, application service layer and user layer. Its main functions included product data management, ASP service, business management, and customer relationship management, its physics framework was a multi-tier internet-based model; the concept of ASP service integration was put forward and its process model was also established. As a result, a networked manufacturing system aimed at the characteristics of reciprocating pump industry was built. By implementing this system, reciprocating pump industry can obtain a new way to fully utilize their own resources and enhance the capabilities to respond to the global market quickly.

Is there reciprocity in preferential trade agreements on services?

OpenAIRE

Marchetti, Juan; Roy, Martin; Zoratto, Laura

2012-01-01

Are market access commitments on services in Preferential Trade Agreements (PTAs) reciprocal or simply unilateral? If reciprocal, do concessions granted in services depend on concessions received from the trading partner in other services or in non-services areas as well? In this paper we investigate the presence of reciprocity in bilateral services agreements, by sub-sector, mode of supply and type of agreement (North-North, South-North, South-South). To do so, we use a database of concessio...

Preschool Teachers use of ICTs

DEFF Research Database (Denmark)

Masoumi, Davoud

2015-01-01

; and as a communication and documentation tool. In addition, by addressing the teachers’ values and attitudes to the role of ICT in early childhood, the paper also unpacks the stances of teachers who consider ICT to be unsuitable for early childhood education. The findings of this study may bring some clarity......This study aimed to identify the ways in which information and communication technologies (ICT) are integrated in three preschools in south-western Sweden. The case study involved observations of and interviews with preschool teachers. The findings support claims that ICT can enhance preschool...

The Traditional in Contemporary Curricula of Preschool Education

Directory of Open Access Journals (Sweden)

Kopas-Vukašinović Emina

2016-02-01

Full Text Available Contemporary curricula of preschool education are the result of the improvement of pedagogical and didactic theories. They imply a technical plan with which it is possible to achieve measurable objectives of preschool education. The curriculum is also defined as a tool for quality and equal education for all. It represents a reflection of the time, society and culture in which it exists, but also a model for future society and education. Thus an important research question arises as to what extent we recognize traditional ideas about learning and the development of a preschool child in contemporary preschool programs. Are traditional ideas about educating young children unjustly neglected or do we recognize them in contemporary pedagogical theory even today, at the same time forgetting about the past and declaring them innovations? This paper deals with the starting points for the development of a curriculum. The goal of the research was to determine to what extent can the starting points for the development of preschool children, which have existed in the first preschool programs in Serbia in the late 19th century, be recognized in contemporary preschool programs. A descriptive method was applied as well as a procedure for content analysis of program documents. Research results confirm that the elements of the first preschool programs, which remain relevant until today, can be recognized in contemporary preschool programs. They are related to target orientations, principles and functions of preschool education. However, these ideas are defined as contemporary tendencies, and the fact that they existed in preschool programs that were developed a long time ago is unjustly ignored.

Sex differences in the reciprocal behaviour of children with autism.

Science.gov (United States)

Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander

2017-08-01

Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.

Who Goes to Preschool and Why Does It Matter? Preschool Policy Brief. Issue 15

Science.gov (United States)

Barnett, W. Steven; Yarosz, Donald J.

2007-01-01

In a world shaped by global competition, preschool education programs play an increasingly vital role in child development and school readiness. There is growing awareness that early learning's impacts persist across children's life spans, affecting educational achievement, adult earning and even crime and delinquency. Preschool education is…

Preschoolers' Performance on the Brazilian Adaptation of the Preschool Language Assessment Instrument - Second Edition.

Science.gov (United States)

Lindau, Tâmara Andrade; Rossi, Natalia Freitas; Giacheti, Celia Maria

2016-01-01

The objective was to test whether the Brazilian version of the Preschool Language Assessment Instrument - Second Edition (PLAI-2) has the potential to assess and identify differences in typical language development of Portuguese-speaking preschoolers. The study included 354 children of both genders with typical language development who were between the ages of 3 years and 5 years 11 months. The version of the PLAI-2 previously translated into Brazilian Portuguese was used to assess the communication skills of these preschool-age children. Statistically significant differences were found between the age groups, and the raw score tended to increase as a function of age. With nonstandardized assessments, the performances of the younger groups revealed behavioral profiles (e.g., nonresponsive, impulsive behavior) that directly influenced the evaluation. The findings of this study show that the PLAI-2 is effective in identifying differences in language development among Brazilian children of preschool age. Future research should include studies validating and standardizing these findings. © 2016 S. Karger AG, Basel.

Reciprocally-Rotating Velocity Obstacles

KAUST Repository

Giese, Andrew; Latypov, Daniel; Amato, Nancy M.

2014-01-01

obstacles. One state-of-the-art local collision avoidance technique is Optimal Reciprocal Collision Avoidance (ORCA). Despite being fast and efficient for circular-shaped agents, ORCA may deadlock when polygonal shapes are used. To address this shortcoming

Affordances of Ditches for Children in Preschool

DEFF Research Database (Denmark)

Lerstrup, Inger Elisabeth; Møller, Maja Steen

2016-01-01

This study aims to expand understanding of the affordances provided by ditches in a Danish preschool context. Affordances are defined as the meaningful action possibilities of the environment. At a forest preschool, a group of 21 children aged approximately 3to 6.5 years accompanied by two to three...... offered varied and changing action possibilities for the preschool children. The paper discusses the possible incorporation of this largely unrecognized design element by planners and managers of green spaces and playgrounds for children in preschool....

BitTorrent's dilemma: Enhancing reciprocity or reducing inequity

NARCIS (Netherlands)

Jia, A.L.; D'Acunto, L.; Meulpolder, M.; Pouwelse, J.A.; Epema, D.H.J.

2011-01-01

Enhancing reciprocity has been one of the primary motivations for the design of incentive policies in BitTorrent-like P2P systems. Reciprocity implies that peers need to contribute their bandwidth to other peers if they want to receive bandwidth in return. However, the over-provisioning that

Guilt driven reciprocity in a psychological signaling game

NARCIS (Netherlands)

Fong, Y.; Huang, C.-Y.; Offerman, T.

2007-01-01

We propose a theory of reciprocity according to which reciprocal behavior is driven by a donor's guilt. Through an experiment we show that subjects respond to factors which induce guilt but do not reflect allocative equity or intention. When the guilt inducing factor is privately observed by the

Guilt driven reciprocity in a psychological signaling game

NARCIS (Netherlands)

Fong, Y.; Huang, C.-Y.; Offerman, T.

2009-01-01

We propose a theory of reciprocity according to which reciprocal behavior is driven by a donor’s guilt. Through an experiment we show that subjects respond to factors which induce guilt but do not reflect allocative equity or intention. When the guilt inducing factor is privately observed by the

Intimate partner violence and preschoolers' explicit memory functioning.

Science.gov (United States)

Jouriles, Ernest N; Brown, Alan S; McDonald, Renee; Rosenfield, David; Leahy, Matthew M; Silver, Cheryl

2008-06-01

This research examines whether parents' intimate partner physical violence (IPV) relates to their preschoolers' explicit memory functioning, whether children's symptoms of hyperarousal mediate this relation, and whether mothers' positive parenting moderates this relation. Participants were 69 mothers and their 4- or 5-year-old child (34 girls). Mothers completed measures of IPV, children's hyperarousal symptoms, parent-child aggression, and positive parenting. Measures of explicit memory functioning were administered to preschoolers. As expected, IPV correlated negatively with preschoolers' performance on explicit memory tasks, even after controlling for parent-child aggression and demographic variables related to preschoolers' memory functioning. Preschoolers' hyperarousal symptoms did not mediate the relation between IPV and explicit memory functioning, but mothers' positive parenting moderated this relation. Specifically, the negative relation between IPV and preschoolers' performance on 2 of the 3 explicit memory tasks was weaker when mothers engaged in higher levels of positive parenting. These findings extend research on IPV and children's adjustment difficulties to explicit memory functioning in preschoolers and suggest that mothers can ameliorate the influence of IPV on preschoolers' memory functioning via their parenting. (c) 2008 APA, all rights reserved

A Comparison of Several Statistical Tests of Reciprocity of Self-Disclosure.

Science.gov (United States)

Dindia, Kathryn

1988-01-01

Reports the results of a study that used several statistical tests of reciprocity of self-disclosure. Finds little evidence for reciprocity of self-disclosure, and concludes that either reciprocity is an illusion, or that different or more sophisticated methods are needed to detect it. (MS)

METHOD OF HISTORICAL RESEARCH OF PRESCHOOL EDUCATION IN RUSSIA

OpenAIRE

Y. S. Rubinchik

2015-01-01

The article suggests a methodology of historical research of preschool education. The analysis of theoretical and methodical provisions for the education of preschool children. Discusses the importance of the achievements of the Soviet system of preschool upbringing and education. Shows the principles, directions, methods and conditions for their implementation when working with children of preschool age. Discusses the state of childhood in modern Russia, problems of development of preschool ...

Communication Patterns in Preschool Education Institutions ? Practical Examples

OpenAIRE

Radic-Hozo, Endica

2014-01-01

Introduction: Proper communication in pre-school institutions for education is undeniable importance to the development of the child, as evidenced by numerous studies. After the child's birth follows the most complex phase in its early phases - preschool education. Only high-quality, synergistic relationship triad: parent-child-educator and the modern postulates of preschool child education, warrants successful preschool child education. Methods and materials: Description, with examples from ...

A theoretical framework for analysing preschool teaching

DEFF Research Database (Denmark)

Chaiklin, Seth

2014-01-01

This article introduces a theoretical framework for analysing preschool teaching as a historically-grounded societal practice. The aim is to present a unified framework that can be used to analyse and compare both historical and contemporary examples of preschool teaching practice within and across...... national traditions. The framework has two main components, an analysis of preschool teaching as a practice, formed in relation to societal needs, and an analysis of the categorical relations which necessarily must be addressed in preschool teaching activity. The framework is introduced and illustrated...

Gendering in one Icelandic preschool

Directory of Open Access Journals (Sweden)

Gudrun Alda Hardardottir

2014-05-01

Full Text Available The aim of this article is to shed light on gendering in preschool. It analyzes the opinions and beliefs of preschool teachers with regard to boys and girls in one Icelandic preschool, and how gender performative acts are manifested in the preschool’s children. The preschool, which was observed for one school year, comprised 60 children, aged 18 months to five years, and 20 employees, of which eight were qualified teachers. The research material is analyzed in terms of Judith Butler’s gender constructivism. Butler contends that gender is constituted by, and is a product of, society, and that the individual’s empowerment is therefore limited in relation to society, with individuals typically seeking to identify themselves with the dominant norms concerning gender. The main conclusions suggest that “gendering” is prominent within the preschool. There is a strong tendency among the preschool teachers to classify the children into categories of boys/masculine and girls/feminine, and specific norms direct the children into the dominant feminine and masculine categories, thus maintaining and reinforcing their gender stereotypes. The children used symbols such as colors, locations and types of play as means to instantiate the “girling” and the “boying”. These findings are consistent with previous Nordic research and indicate a prevailing essentialist perspective towards both girls and boys. The originality of the research, however, lies in focusing on children’s gender from the individual’s perspective and how the individual child generally enacts gender performatively within the confines of society’s norms.

The stability of quadratic-reciprocal functional equation

Science.gov (United States)

Song, Aimin; Song, Minwei

2018-04-01

A new quadratic-reciprocal functional equation f ((k +1 )x +k y )+f ((k +1 )x -k y )=2/f (x )f (y )[(k+1 ) 2f (y )+k2f (x )] [(k+1)2f (y )-k2f (x )] 2 is introduced. The Hyers-Ulam stability for the quadratic-reciprocal functional equations is proved in Banach spaces using the direct method and the fixed point method, respectively.

Reciprocity principle in stochastic quantum mechanics

International Nuclear Information System (INIS)

Brooke, J.A.; Guz, W.; Prugovecki, E.

1982-01-01

Born's reciprocity theory can be combined with a recently proposed framework for quantum spacetime by requiring that the free test particle propagators obey the Born-Lande equation in addition to the Klein-Gordon equation. If, furthermore, the coordinate transition amplitudes in between various standards are required to be eigenfunctions of Born's metric operator, then a mass formula results which predicts linear dependence on spin of the squared rest mass of elementary particles. This procedure also leads to a guage and reciprocally invariant formulation of the relativistic canonical commutation relations

Payoff non-linearity sways the effect of mistakes on the evolution of reciprocity.

Science.gov (United States)

Kurokawa, Shun

2016-09-01

The existence of cooperation is considered to require explanation, and reciprocity is a potential explanatory mechanism. Animals sometimes fail to cooperate even when they attempt to do so, and a reciprocator has an Achilles' heel: it is vulnerable to error (the interaction between two reciprocators can lead to an endless vendetta.). However, the strategy favored by natural selection is determined also by its interaction with other strategies. The relationship between two reciprocators leading to a collapse of cooperation through error does not straightforwardly imply that mistakes make the conditions under which reciprocity evolves stringent. Hence, mistakes may facilitate the evolution of reciprocity. However, it has been shown through the analysis of the interaction between reciprocators and unconditional defectors that the existence of mistakes makes the conditions for reciprocators stable against invasion by an unconditional defector more stringent, which indicates that mistakes discourage the evolution of reciprocity. However, this result is based on the assumption that the effects of cooperation are additive (payoff is linear), while the game played by real animals does not always display this feature. In such cases, the result may be swayed. In this paper, we remove this assumption, reexamining whether mistakes disturb the evolution of reciprocity. Using the analysis of an evolutionarily stable strategy (ESS), we show that when extra fitness costs are present in cases where mutual cooperation is established, mistakes can facilitate the evolution of reciprocity; whereas, when the effect of cooperation is additive, mistakes always disturb the evolution of reciprocity, as has been shown previously. Copyright © 2016. Published by Elsevier Inc.

Hidden Spaces and Places in the Preschool: Withdrawal Strategies in Preschool Children's Peer Cultures

Science.gov (United States)

Skanfors, Lovisa; Lofdahl, Annica; Hagglund, Solveig

2009-01-01

The article discusses how children make use of their preschool context in order to withdraw. Ethnographic observations were made of two-to five-year-old children's interactions during free play and teacher-led activities in the preschool, and documentation was carried out through field notes and video recordings. The empirical material was…

Reciprocity and depressive symptoms in Belgian workers: a cross-sectional multilevel analysis.

Science.gov (United States)

De Clercq, Bart; Clays, Els; Janssens, Heidi; De Bacquer, Dirk; Casini, Annalisa; Kittel, France; Braeckman, Lutgart

2013-07-01

This study examines the multidimensional association between reciprocity at work and depressive symptoms. Data from the Belgian BELSTRESS survey (32 companies; N = 24,402) were analyzed. Multilevel statistical procedures were used to account for company-level associations while controlling for individual-level associations. Different dimensions of individual reciprocity were negatively associated with depressive symptoms. On the company level, only vertical emotional reciprocity was negatively associated (β = -4.660; SE = 1.117) independently from individual reciprocity (β = -0.557; SE = 0.042). Complex interactions were found such that workplace reciprocity (1) may not uniformly benefit individuals and (2) related differently to depressive symptoms, depending on occupational group. This study extends the existing literature with evidence on the multidimensional, contextual, and cross-level interaction associations of reciprocity as a key aspect of social capital on depressive symptoms.

Monkeys fail to reciprocate in an exchange task.

Science.gov (United States)

Pelé, Marie; Thierry, Bernard; Call, Josep; Dufour, Valérie

2010-09-01

Exchanges form the basis of human economies. Animals too can engage in reciprocal interactions but they do not barter goods like humans, which raises the question of the abilities necessary for trading to occur. Previous studies have shown that non-human primates can exchange food with human partners. Here, we tested the ability of brown capuchin monkeys and Tonkean macaques to reciprocate in a task requiring two conspecifics to exchange tokens in order to obtain rewards from an experimenter. We recorded 56 transfers between subjects in capuchin monkeys and 10 in Tonkean macaques. All transfers were passive in both species. Capuchins preferentially picked up tokens valuable for them in the partner's compartment. They tended to manipulate the partner-valued tokens more often than the no-value ones, leading to more opportunities for these tokens to end up within reach of the partner. Despite optimal conditions where values of goods were defined and known by partners, however, none of the pairs tested engaged in short-term reciprocal interactions. These results indicate that calculated reciprocity was difficult if not impossible in the animals tested.

Grooming reciprocity in female tibetan macaques macaca thibetana.

Science.gov (United States)

Xia, Dongpo; Li, Jinhua; Garber, Paul A; Sun, Lixing; Zhu, Yong; Sun, Binghua

2012-06-01

Grooming among nonhuman primates is widespread and may represent an important service commodity that is exchanged within a biological marketplace. In this study, using focal animal sampling methods, we recorded grooming relationships among 12 adult females in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China, to determine the influence of rank and kinship on grooming relationships, and whether females act as reciprocal traders (exchange grooming received for grooming given) or interchange traders (interchange grooming for social tolerance or other commodities). The results showed that: (1) grooming given was positively correlated with grooming received; (2) kinship did not exert a significant influence on grooming reciprocity; and (3) grooming reciprocity occurred principally between individuals of adjacent rank; however, when females of different rank groomed, females tended to groom up the hierarchy (lower ranking individuals groomed higher ranking individuals more than vice versa). Our results support the contention that both grooming reciprocity and the interchange of grooming for tolerance represent important social tactics used by female Tibetan macaques. © 2012 Wiley Periodicals, Inc.

Disjunctured reciprocity: Paradoxes of community-school relationship in Nepal

DEFF Research Database (Denmark)

Pradhan, Uma; Shrestha, Shivana; Valentin, Karen

2018-01-01

and community. This article questions the simplistic assumption through an ethnographic study of community-school relationship in Nepal. While these relationships may conflict with the kind of reciprocity assumed in school governance policies, we argue that this disjunctured reciprocity, firstly, reflects...

Physical Activity and Health in Preschool Children

DEFF Research Database (Denmark)

Christensen, Line Brinch

Physical activity is beneficial in relation to several life style diseases and the association between physical activity and early predictors of life style diseases seem to be present already in preschool age. Since physical activity and other health behaviours are established during childhood...... and track from childhood into adult life, it is relevant to address physical activity already in the preschool age. The research in preschool children’s physical activity is relatively new, and because of methodological inconsistencies, the associations between physical activity and health are less clear...... in this age group. The objective of this thesis was to contribute to the knowledge base regarding physical activity in preschoolers; How active are preschoolers? Are activity levels related to specific settings during a typical week? And are the activity levels related to a range of health outcomes...

Social games with pre-school children

OpenAIRE

Tomažin, Maja

2013-01-01

The aim of the thesis Social games with pre-school children is to present social games as one of the work methods for relational learning. The theoretical part defines the social development of pre-school children and focuses on social skills that begin to emerge in the preschool period and of course social games. The purpose of social games is active learning, meaning they provide concrete situations, through which children actively learn as well as use social skills and express their views ...

Effect of load and reciprocating velocity on the transition from mild to severe wear behavior of Al-Si-SiCp composites in reciprocating conditions

International Nuclear Information System (INIS)

Rajeev, V.R.; Dwivedi, D.K.; Jain, S.C.

2010-01-01

In the present paper, the effect of normal load and reciprocating velocity on transition from mild to severe wear of A319/15%SiC p , A336/15%SiC p , and A390/15%SiC p composites have been reported. Composites were produced through liquid metal metallurgy route. Adhesive wear behavior of composites was studied under dry reciprocating conditions using indigenously developed reciprocating friction wear test rig conforming to ASTM Standard G133-05. It was found that increase in normal load increases wear rate and depending upon the reciprocating velocity and type of composites, mode of wear changes from mild oxidative to severe metallic wear was noticed. The load corresponding to the transition from mild to severe wear usually termed as transition load was found to decrease with increase in reciprocating velocity and reduction in silicon content in the alloys used for the development of Al-Si-SiC p composites. At 1 m/s reciprocating velocity, the transition load for A319/15%SiC p , A336/15%SiC p and A390/15%SiC p composites were found to be in the range of 60-90 N, 60-105 N and 60-120 N respectively. Scanning electron microscope (SEM) study of wear surface and wear debris were conducted to analyze the mode of wear and operating wear mechanism. Severe wear was characterized by massive plastic deformation and gross material removal while the mild wear was found to be associated with delamination and scoring as main wear mechanisms responsible for material loss. Wear mechanism maps for different Al-(6-18)%Si-15%SiC p composites were proposed in reciprocating contacts.

Green Settings for Children in Preschools

DEFF Research Database (Denmark)

Lerstrup, Inger Elisabeth

settings for preschools. The intent is to facilitate transfer of knowledge from preschools to planners and managers of green settings such as woodland, parks, green lots and playgrounds. The central concept applied is that of affordances, here defined as the meaningful action possibilities......This Danish study investigates the relationship between children in preschool (age range 3-6.5 years) and the outdoor environments they use. The main aim is to describe and analyse the outdoor features of significance for children’s activities and of importance for design and management of green...... between forest features and manufactured features, a detailed account of the affordances of ditches, and a description of the forest sites used by a Danish forest preschool. Children were attracted to features with changing and not fully explored action possibilities; forest features added variation...

Direct in situ thermometry: Variations in reciprocal-lattice vectors and challenges with the Debye–Waller effect

International Nuclear Information System (INIS)

Cremons, Daniel R.; Flannigan, David J.

2016-01-01

Conventional in situ transmission electron microscopy (TEM) enables the atomic-scale study of dynamic materials processes on millisecond time scales. Specimen holders capable of being heated to over 1000 °C have provided insight into myriad processes, including nanoscale thermal transport, structural phase transitions, and catalytic reactions. In order for such studies to be accurate and precise, direct determination of the specimen temperature – rather than the heating-element temperature – is critical. Further, such methods should be versatile in that any temperature across a wide range may be measured, irrespective of single-indicator properties specific to the specimen (e.g., first-order phase transition, melting point, etc.). Here, we describe a rigorous approach to direct, in situ thermometry of TEM specimens that exploits lattice thermal expansion and the resultant decrease in diffraction-vector magnitude in reciprocal space. Via sub-pixel measurement of reciprocal-lattice-vector magnitudes, picometer increases in lattice parameters are measured over a continuous temperature range and compared to those expected from the coefficient of thermal expansion. Statistical treatment of several experimental trials conducted on nanostructured aluminum thin films shows excellent agreement with both theory and (indirect) measurement of the in situ heating holder. Additionally, we illustrate how uncontrolled, thermally-induced variation in single-crystal orientation leads to modulation of the excitation error and, therefore, the Bragg-spot intensities resulting in a convolution of heating and tilting effects, thus complicating temperature determination via the Debye–Waller effect. - Highlights: • A method for direct in situ determination of specimen temperature is described. • Specimen temperature is determined via reciprocal-lattice-vector contraction. • Statistical treatment agrees with the in situ heating-holder thermocouple reading. • Thermally

Systematic Quality Work in Preschool

Science.gov (United States)

Sheridan, Sonja; Williams, Pia; Sandberg, Anette

2013-01-01

The purpose of this study was to investigate the meaning that Swedish preschool teachers ascribe to systematic quality work. In Sweden, all preschools are required to work systematically with quality issues. This involves several interdependent steps that follow each other in a specific order. Although the concept of systematic quality work might…

Motor competence and characteristics within the preschool environment.

Science.gov (United States)

True, Larissa; Pfeiffer, Karin Allor; Dowda, Marsha; Williams, Harriet G; Brown, William H; O'Neill, Jennifer R; Pate, Russell R

2017-08-01

Environmental characteristics within preschools that influence children's motor competence are largely unknown. The purpose of the present study was to examine the contribution of various preschool environmental characteristics to children's locomotor, object control, and total gross motor scores. Cross-sectional, observational study of 3-5 year-old children (n=229) from 22 preschools in South Carolina. The Children's Activity and Movement in Preschool Study (CHAMPS) Motor Skills Protocol assessed MC. Preschool directors provided information regarding policies and practices. The research team measured playgrounds and classrooms, and the Early Childhood Environment Rating Scale-Revised assessed preschool quality. Time spent in open space and electronic media use were also assessed using direct observation. The aforementioned variables predicted children's object control, locomotor, and total gross motor scores. Classroom size/child ratio, teacher education, playground size, electronic media use, and trips to outside organizations emerged as significant predictors of locomotor score and total motor score. The object control model was non-significant. Preschools may be able to promote motor competence by allowing children more time in open spaces, structured activity experiences, and by expanding existing outdoor playground space whenever possible. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Advances in Design and Fabrication of Free-Form Reciprocal Structures

DEFF Research Database (Denmark)

Parigi, Dario

2016-01-01

The paper presents the advances in design and fabrication of free-form Reciprocal Structures, and their application a during a one-week long workshop with the students of the 1st semester of the Master of Science in Architecture and Design, fall 2015, at Aalborg University. Two new factors were...... introduced and tested: a new version of the software Reciprocalizer, and an evolution of the Reciprocalizer Robot. The workshop didactic framework Performance Aided/Assisted Design (PAD) is presented....

The Situated Nature of Preschool Children's Conflict Strategies

Science.gov (United States)

Thornberg, Robert

2006-01-01

The purpose of this study was to examine whether the peer conflict strategies of preschool children are situated and therefore vary across different conflict situations. Hypothetical conflict interviews were administered through a series of puppet shows. Participants were 178 preschool children. Results indicate that preschool children's conflict…

Reciprocally-Rotating Velocity Obstacles

KAUST Repository

Giese, Andrew

2014-05-01

© 2014 IEEE. Modern multi-agent systems frequently use highlevel planners to extract basic paths for agents, and then rely on local collision avoidance to ensure that the agents reach their destinations without colliding with one another or dynamic obstacles. One state-of-the-art local collision avoidance technique is Optimal Reciprocal Collision Avoidance (ORCA). Despite being fast and efficient for circular-shaped agents, ORCA may deadlock when polygonal shapes are used. To address this shortcoming, we introduce Reciprocally-Rotating Velocity Obstacles (RRVO). RRVO generalizes ORCA by introducing a notion of rotation for polygonally-shaped agents. This generalization permits more realistic motion than ORCA and does not suffer from as much deadlock. In this paper, we present the theory of RRVO and show empirically that it does not suffer from the deadlock issue ORCA has, permits agents to reach goals faster, and has a comparable collision rate at the cost of performance overhead quadratic in the (typically small) user-defined parameter δ.

Peer Effects on Head Start Children’s Preschool Competency

Science.gov (United States)

DeLay, Dawn; Hanish, Laura D.; Martin, Carol Lynn; Fabes, Richard A.

2015-01-01

The goals of the present study were to investigate whether young children attending Head Start (N=292; Mage=4.3 years) selected peers based on their preschool competency and whether children’s levels of preschool competency were influenced by their peers’ levels of preschool competency. Children’s peer interaction partners were intensively observed several times a week over one academic year. Social network analyses revealed that children selected peer interaction partners with similar levels of preschool competency and were influenced over time by their partners’ levels of preschool competency. These effects held even after controlling for several child (e.g., sex and language) and family factors (e.g., financial strain and parent education). Implications for promoting preschool competency among Head Start children are discussed. PMID:26479545

Preschool Personnel Exposure to Occupational Noise

Directory of Open Access Journals (Sweden)

Kaļužnaja Darja

2016-10-01

Full Text Available Increased noise, which is also below the occupational exposure values and is “hearing safe” noise, affects the exposed person’s health as a non-specific stressor. Increased noise level also creates an environment for additional vocal apparatus load. The objective of this study was to determine preschool personnel occupational noise and its relationship with subjective health complaints. Data were obtained with survey assistance through subjective answers of respondents about health complaints and noise exposure among Rīga preschool personnel. Objective noise measurements were made to assess real noise levels in the preschool environment. Data from 155 respondents and objective measurements of 37 preschool classrooms were obtained. The results showed that the average 8-h noise exposure among Rīga preschool educational institutions was 70 dB(A, which did not exceed the Latvian work environment noise limits, but exceeded the 35–40 dB(A noise limit in the educational environment guidelines recommended by the WHO. The survey results showed that loud noise is one of the most important workplace environmental factors (~70% of respondents feel a necessity to increase voice because of noise. A constant feeling of fatigue, headache, irritable feeling, and a desire to isolate oneself from others more often occurred in respondents exposed to increased noise, compared with those who noted that they were not exposed to increased noise. In general, loud noise was associated with increased subjective health complaints in preschool education institution personnel.

Literature review on the preschool pedestrian

Science.gov (United States)

1985-01-01

The purpose of this literature review was to describe (1) the factors leading to typical preschool pedestrian accidents, (2) the developmental characteristics of the preschool child that affect his/her behavior in traffic, (3) social factors that may...

Anaemia, Nutritional Status and Parasitic Infection among Preschool ...

African Journals Online (AJOL)

Objective: This study was carried out to determine the packed cell volume nutritional status and parasitic infection among preschool children living in rural villages. Subjects and Methods: A total of 116 preschool children in nine villages formed the population for this study. The preschool children were studied using ...

Integration of Interactive Whiteboard in Swedish Preschool Practices

Science.gov (United States)

Bourbour, Maryam; Vigmo, Sylvi; Samuelsson, Ingrid Pramling

2015-01-01

This paper aims at exploring the roles preschool teachers give technologies in mathematics education and the ways they structure their mathematics learning activities using interactive whiteboard (IWB) as a technological artefact. Data collected from observations of three preschool teachers embedding IWB in a preschool practice in Sweden provided…

Evidence of Reciprocity in Reports on International Partnerships

Directory of Open Access Journals (Sweden)

Rachel A. Umoren

2012-01-01

Full Text Available The increase in global health opportunities in medical education has been accompanied by calls for ethical and reciprocal institutional partnerships. The Working Group on Ethics Guidelines in Global Health Training (WEIGHT guidelines were developed in 2010 and are widely accepted by the global health community. We reviewed 43 articles on international partnerships from 1970 to 2010 for eight principles of reciprocity derived from the WEIGHT guidelines. The results showed that, while few articles reflected all principles, there was a trend to increasing consideration of the international partner’s local needs, pre-departure cultural training, and collaborative authorship. However, learner supervision and consideration of local cost/benefit ratios decreased over the same time period. Partnerships with only one international partner or with institutional partners in Africa had lower reciprocity scores than those with two or more partners and institutional partners in Asia and South America. We recommend that a new focus on ethics in global health partnerships leads to the inclusion of the principles of reciprocity in model program descriptions in order to enable and encourage ethical, sustainable, and mutually beneficial institutional partnerships.

Children´s and Preschool Teacher´s Photographs of New Preschool Architecture

DEFF Research Database (Denmark)

Rasmussen, Kim

In an ongoing project (2013-2014) about children´s and preschool teacher´s interactions with and experiences of new architecture/physical environment, young children between 2-5 years and their preschool teachers has photographed the physical and social environment. A numbers of photo...... architecture. The architecture in new childcare-institutions breaks on several points with the former idea of "kindergarten" (small environments with an emphasis on domesticity, development and play). The new preschools in Denmark are bulky, contains many children (some more than 200 children), and are highly...... transparent (widespread use of glass in both interior and exterior walls). The new architecture is based on (neoliberal) ideas of flexibility and puts the emphasis on early childhood learning. But one thing is the ideas of politicians, architects and builders, another is how the buildings are "lived...

Gauge invariance and reciprocity in quantum mechanics

International Nuclear Information System (INIS)

Leung, P. T.; Young, K.

2010-01-01

Reciprocity in wave propagation usually refers to the symmetry of the Green's function under the interchange of the source and the observer coordinates, but this condition is not gauge invariant in quantum mechanics, a problem that is particularly significant in the presence of a vector potential. Several possible alternative criteria are given and analyzed with reference to different examples with nonzero magnetic fields and/or vector potentials, including the case of a multiply connected spatial domain. It is shown that the appropriate reciprocity criterion allows for specific phase factors separable into functions of the source and observer coordinates and that this condition is robust with respect to the addition of any scalar potential. In the Aharonov-Bohm effect, reciprocity beyond monoenergetic experiments holds only because of subsidiary conditions satisfied in actual experiments: the test charge is in units of e and the flux is produced by a condensate of particles with charge 2e.

Transcranial electrical neuromodulation based on the reciprocity principle

Directory of Open Access Journals (Sweden)

Mariano eFernandez Corazza

2016-05-01

Full Text Available A key challenge in multi-electrode transcranial electrical stimulation (TES or transcranial direct current stimulation (tDCS is to find a current injection pattern that delivers the necessary current density at a target and minimizes it in the rest of the head, which is mathematically modelled as an optimization problem. Such an optimization with the Least Squares (LS or Linearly Constrained Minimum Variance (LCMV algorithms is generally computationally expensive and requires multiple independent current sources. Based on the reciprocity principle in electroencephalography (EEG and TES, it could be possible to find the optimal TES patterns quickly whenever the solution of the forward EEG problem is available for a brain region of interest. Here, we investigate the reciprocity principle as a guideline for finding optimal current injection patterns in TES that comply with safety constraints. We define four different trial cortical targets in a detailed seven-tissue finite element head model, and analyze the performance of the reciprocity family of TES methods in terms of electrode density, targeting error, focality, intensity, and directionality using the LS and LCMV solutions as the reference standards. It is found that the reciprocity algorithms show good performance comparable to the LCMV and LS solutions. Comparing the 128 and 256 electrode cases, we found that use of greater electrode density improves focality, directionality, and intensity parameters. The results show that reciprocity principle can be used to quickly determine optimal current injection patterns in TES and help to simplify TES protocols that are consistent with hardware and software availability and with safety constraints.

Transcranial Electrical Neuromodulation Based on the Reciprocity Principle.

Science.gov (United States)

Fernández-Corazza, Mariano; Turovets, Sergei; Luu, Phan; Anderson, Erik; Tucker, Don

2016-01-01

A key challenge in multi-electrode transcranial electrical stimulation (TES) or transcranial direct current stimulation (tDCS) is to find a current injection pattern that delivers the necessary current density at a target and minimizes it in the rest of the head, which is mathematically modeled as an optimization problem. Such an optimization with the Least Squares (LS) or Linearly Constrained Minimum Variance (LCMV) algorithms is generally computationally expensive and requires multiple independent current sources. Based on the reciprocity principle in electroencephalography (EEG) and TES, it could be possible to find the optimal TES patterns quickly whenever the solution of the forward EEG problem is available for a brain region of interest. Here, we investigate the reciprocity principle as a guideline for finding optimal current injection patterns in TES that comply with safety constraints. We define four different trial cortical targets in a detailed seven-tissue finite element head model, and analyze the performance of the reciprocity family of TES methods in terms of electrode density, targeting error, focality, intensity, and directionality using the LS and LCMV solutions as the reference standards. It is found that the reciprocity algorithms show good performance comparable to the LCMV and LS solutions. Comparing the 128 and 256 electrode cases, we found that use of greater electrode density improves focality, directionality, and intensity parameters. The results show that reciprocity principle can be used to quickly determine optimal current injection patterns in TES and help to simplify TES protocols that are consistent with hardware and software availability and with safety constraints.

Efficient Design And Fabrication Of Free-Form Reciprocal Structures

DEFF Research Database (Denmark)

Parigi, Dario; Kirkegaard, Poul Henning

2013-01-01

Structures based on the principle of reciprocity have been autonomously studied and used since the antiquity on the basis of different needs and purposes. The application of the principle of reciprocity requires the presence of at least two elements, at the same time both supporting and being sup...

Apical extrusion of debris using reciprocating files and rotary ...

African Journals Online (AJOL)

Procedure: Sixty extracted human mandibular premolars were used. The root canals were instrumented using reciprocating (WaveOne, Reciproc, SafeSider) or rotary ... and cross‑sections, and kinematics, and this situation may influence the amount of apically extruded debris through the apical foramen.[15]. The aim of this ...

Coordinated vigilance provides evidence for direct reciprocity in coral reef fishes.

Science.gov (United States)

Brandl, Simon J; Bellwood, David R

2015-09-25

Reciprocity is frequently assumed to require complex cognitive abilities. Therefore, it has been argued that reciprocity may be restricted to animals that can meet these demands. Here, we provide evidence for the potential presence of direct reciprocity in teleost fishes. We demonstrate that in pairs of coral reef rabbitfishes (f. Siganidae), one fish frequently assumes an upright vigilance position in the water column, while the partner forages in small crevices in the reef substratum. Both behaviours are strongly coordinated and partners regularly alternate their positions, resulting in a balanced distribution of foraging activity. Compared to solitary individuals, fishes in pairs exhibit longer vigilance bouts, suggesting that the help provided to the partner is costly. In turn, fishes in pairs take more consecutive bites and penetrate deeper into crevices than solitary individuals, suggesting that the safety provided by a vigilant partner may outweigh initial costs by increasing foraging efficiency. Thus, the described system appears to meet all of the requirements for direct reciprocity. We argue that the nature of rabbitfish pairs provides favourable conditions for the establishment of direct reciprocity, as continuous interaction with the same partner, simultaneous needs, interdependence, and communication relax the cognitive demands of reciprocal cooperation.

Print Knowledge of Preschool Children with Hearing Loss

Science.gov (United States)

Werfel, Krystal L.; Lund, Emily; Schuele, C. Melanie

2015-01-01

Measures of print knowledge were compared across preschoolers with hearing loss and normal hearing. Alphabet knowledge did not differ between groups, but preschoolers with hearing loss performed lower on measures of print concepts and concepts of written words than preschoolers with normal hearing. Further study is needed in this area.

The Normative Foundation of Legal Orders: A Balance between Reciprocity and Mutuality

NARCIS (Netherlands)

Pessers, D.

2014-01-01

Reciprocity seems to figure as a self-evident normative foundation of legal orders. Yet a clear understanding of the often opaque role that reciprocity plays in this regard demands drawing a conceptual distinction. This article views reciprocity as a social morality of duties, in opposition to

"Dentinal microcracks after root canal preparation" a comparative evaluation with hand, rotary and reciprocating instrumentation.

Science.gov (United States)

Priya, N Tulasi; Chandrasekhar, Veeramachaneni; Anita, S; Tummala, Muralidhar; Raj, T B Phanindhar; Badami, Vijetha; Kumar, Pradeep; Soujanya, E

2014-12-01

The purpose of this study was to compare the incidence of dentinal micro cracks after instrumentation with various types of NiTi files in rotary and reciprocating motion. One hundred human extracted mandibular central incisors were taken and divided into 10 groups (n=10 teeth per group). Group 1- No preparation, Group 2 - Hand instrumentation, Groups 3,4 - ProTaper files in rotary and reciprocating motion, Groups 5,6 - ProTaper Next files in rotary and reciprocating motion, Groups 7,8 - Oneshape files in rotary and reciprocating motion, Groups 9,10 - Reciproc files in rotary and reciprocating motion. Specimens were sectioned horizontally at 3,6 and 9 mm from the apex and dentinal micro cracks were observed under a stereomicroscope. There was a statistically significant difference between the groups (pProtaper Next - Rot, Protaper Next - Rec, Reciproc - Rec); (ProTaper - Rot, ProTaper - Rec, Oneshape - Rot), (Oneshape - Rot, Reciproc - Rot), (One shape Reciproc, Reciproc - Rec); (p >.05). Least cracks were seen in canals instrumented with Pro Taper Next files both in rotary and reciprocating motion. Full sequence rotary systems showed less cracks than single file systems and full sequence rotary systems showed less cracks in reciprocating motion than in rotary motion.

The general chain transform and self-reciprocal functions

Directory of Open Access Journals (Sweden)

Cyril Nasim

1985-01-01

Full Text Available A theory of a generalized form of the chain transforms of order n is developed, and various properties of these are established including the Parseval relation. Most known cases of the standard theory are derived as special cases. Also a theory of self-reciprocal functions is given, based on these general chain transforms; and relations among various classes of self-reciprocal functions are established.

Perceptions of intimacy and friendship reciprocity moderate peer influence on aggression.

Science.gov (United States)

Meter, Diana J; Casper, Deborah M; Card, Noel A

2015-01-01

Previous research has shown that close friends' influence can exacerbate adolescents' aggressive behavior, but results of studies which examine whether friendships of greater or lesser qualities moderate peer influence effects are inconsistent. The present study tested whether the perception of the positive friendship quality of intimate exchange and friendship reciprocity moderated best friend influence on participant aggression over time. The 243 participants were approximately 12 years old and ethnically diverse. Neither intimate exchange nor reciprocity significantly moderated friend influence on aggression in a simple way, but the interaction of intimate exchange and friendship reciprocity predicted peer influence on participants' aggression over time. Specifically, highly intimate, nonreciprocal best friendships and less intimate, reciprocal best friendships showed greatest influence when friends' proportion of peer nominations for aggression was high. Reciprocity and intimacy should be considered when predicting peer influence on aggression. © 2014 Wiley Periodicals, Inc.

Factors of the active listening of preschool children

Directory of Open Access Journals (Sweden)

Purić Daliborka S.

2016-01-01

Full Text Available Active listening is a communication skill which is crucial for the development of cooperative relationships in the group, culture of friendship and fellowship, it is also important for the development of literacy skills and talent for speaking. Furthermore, it contributes to the improvement of the level of knowledge, skills and school achievement, as well as to the development of self-confidence of children. Developing of active listening is an important task in the activities with children of preschool age. In this paper, the author, wanting to determine the importance of the factors of active listening of preschool children, examines how preschool teachers (N = 198: (a evaluate the importance of certain elements of active listening that relate to the speaker and the listener, and (b estimate their role in the process of developing active listening skills of preschool children as an essential element of successful interpersonal communication. Results of the survey show that preschool teachers attach greater importance to the factors of active listening related to the listener (attention, listening skill, interest in the subject, than to the factors related to the speaker (motivation for listening, quality of the narrative. More than two-thirds of surveyed preschool teachers (172 or 86.9% define its impact on the stimulation of active listening of children as significant. Work experience and professional qualifications as independent variables significantly influence the attitudes of preschool teachers about the importance of their impact in stimulating active listening. Preschool teacher is a key element of the training of preschool children in the area of the basic communication skills of active listening. In this sense, the results of our survey show that in the context of academic study programs for education of preschool teachers special attention is given to the communication skills and to their role in the development of active listening

Effectiveness of a Danish early year preschool program

DEFF Research Database (Denmark)

Jensen, Bente; Holm, Anders; Bremberg, Sven

2013-01-01

A significant number of studies indicate that early year preschool programs lead to positive long-term effects. Systematic quality improvement of early year preschool may enhance these outcomes. The ASP Program was built on this principle. In this program preschool staff are supported...... in their efforts to critically reflect on current practices and to change these. A randomized controlled study was carried out in Denmark from September 2006 to May 2008. The study encompassed 2323 children in 59 preschools in two municipalities. Children were assessed using the Strength and Difficulties...

Supersymmetric reciprocal transformation and its applications

International Nuclear Information System (INIS)

Liu, Q. P.; Popowicz, Ziemowit; Tian Kai

2010-01-01

The supersymmetric analog of the reciprocal transformation is introduced. This is used to establish a transformation between one of the supersymmetric Harry Dym equations and the supersymmetric modified Korteweg-de Vries equation. The reciprocal transformation, as a Baecklund-type transformation between these two equations, is adopted to construct a recursion operator for the supersymmetric Harry Dym equation. By proper factorization of the recursion operator, a bi-Hamiltonian structure is found for the supersymmetric Harry Dym equation. Furthermore, a supersymmetric Kawamoto equation is proposed and is associated with the supersymmetric Sawada-Kotera equation. The recursion operator and odd bi-Hamiltonian structure of the supersymmetric Kawamoto equation are also constructed.

Enhanced additive manufacturing with a reciprocating platen

Science.gov (United States)

Lind, Randall F.; Blue, Craig A.; Love, Lonnie J.; Post, Brian K.; Lloyd, Peter D.

2018-02-06

An additive manufacturing extrusion head that includes a heated nozzle for accepting a feedstock and extruding the feedstock onto a substrate at a deposition plane, the nozzle having a longitudinal extrusion axis. A reciprocating platen surrounds the nozzle, the platen operable to reciprocate along the extrusion axis at or above the deposition plane as the nozzle extrudes feedstock onto the substrate; and wherein the platen flattens the extruded feedstock such that it does not protrude above the deposition plane as the extrusion head traverses over the substrate.

Structural Implications of Reciprocal Exchange: A Power-Dependence Approach

Science.gov (United States)

Bonacich, Phillip; Bienenstock, Elisa Jayne

2009-01-01

This paper presents and tests a general model to predict emergent exchange patterns and power differences in reciprocal exchange networks when individual actors follow the norm of reciprocity. With an interesting qualification, the experimental results reported here support the power-dependence approach (Emerson 1972a, b): those who acquire the…

Making Oneself Heard--Children's Experiences of Empowerment in Swedish Preschools

Science.gov (United States)

Almqvist, Anna-Lena; Almqvist, Lena

2015-01-01

Children's experiences of empowerment in relation to preschool peers and in child-adult interactions were studied, involving 25 four- to six-year-olds from four Swedish preschools. Group interviews using puppets comprised pre-constructed scenarios to examine preschools' activities. Children took photos of indoor and outdoor preschool environments,…

Positioning masculinities and femininities in preschool EFLl1 education

OpenAIRE

CASTAÑEDA-PEÑA, HAROLD

2008-01-01

Positioning Masculinities and Femininities in Preschool EFL Education seeks to describe and interpret how masculinities and femininities are communicated in the preschool EFL classroom and is aimed at discussing whether those masculinities and femininities are likely to have an impact on the preschoolers' learning of English as a foreign language. Preschoolers' classroom interactions taking place in a Colombian kindergarten, videotaped from 2004 to 2006, are analysed via ideas of 'positioning...

Incidence of dentinal defects after root canal preparation: reciprocating versus rotary instrumentation.

Science.gov (United States)

Bürklein, Sebastian; Tsotsis, Polymnia; Schäfer, Edgar

2013-04-01

The purpose of this study was to evaluate the incidence of dentinal defects after root canal preparation with reciprocating instruments (Reciproc and WaveOne) and rotary instruments. One hundred human central mandibular incisors were randomly assigned to 5 groups (n = 20 teeth per group). The root canals were instrumented by using the reciprocating single-file systems Reciproc and WaveOne and the full-sequence rotary Mtwo and ProTaper instruments. One group was left unprepared as control. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex and evaluated under a microscope by using 25-fold magnification. The presence of dentinal defects (complete/incomplete cracks and craze lines) was noted and analyzed by using the chi-square test. No defects were observed in the controls. All canal preparation created dentinal defects. Overall, instrumentation with Reciproc was associated with more complete cracks than the full-sequence files (P = .021). Although both reciprocating files produced more incomplete cracks apically (3 mm) compared with the rotary files (P = .001), no statistically significant differences were obtained concerning the summarized values of all cross sections (P > .05). Under the conditions of this study, root canal preparation with both rotary and reciprocating instruments resulted in dentinal defects. At the apical level of the canals, reciprocating files produced significantly more incomplete dentinal cracks than full-sequence rotary systems (P < .05). Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

45 CFR 84.38 - Preschool and adult education.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Preschool and adult education. 84.38 Section 84.38..., and Secondary Education § 84.38 Preschool and adult education. A recipient to which this subpart applies that provides preschool education or day care or adult education may not, on the basis of handicap...

Swedish Preschool Leadership--Supportive of Music or Not?

Science.gov (United States)

Ehrlin, Anna

2015-01-01

This study uses observations and interviews to investigate how the leadership at three Swedish preschools in Sweden has impacted the didactic choices made. Two of these preschools use music as a tool for stimulating language and social development, while the third preschool serves as a comparison. The inspiration that the leadership has brought to…

Reciprocity in the electronic stopping of slow ions in matter

International Nuclear Information System (INIS)

Sigmund, P.

2008-01-01

The principle of reciprocity, i.e., the invariance of the inelastic excitation in ion-atom collisions against interchange of projectile and target, has been applied to the electronic stopping cross section of low-velocity ions and tested empirically on ion-target combinations supported by a more or less adequate amount of experimental data. Reciprocity is well obeyed (within ∼10%) for many systems studied, and deviations exceeding ∼20% are exceptional. Systematic deviations such as gas-solid or metal-insulator differences have been looked for but not identified on the present basis. A direct consequence of reciprocity is the equivalence of Z 1 with Z 2 structure for random slowing down. This feature is reasonably well supported empirically for ion-target combinations involving carbon, nitrogen, aluminium and argon. Reciprocity may be utilized as a criterion to reject questionable experimental data. In cases where a certain stopping cross section has not been or cannot be measured, the stopping cross section for the inverted system may be available and serve as a first estimate. It is suggested to build in reciprocity as a fundamental requirement into empirical interpolation schemes directed at the stopping of low-velocity ions. Examination of the SRIM and MSTAR codes reveals cases where reciprocity is obeyed accurately, but deviations of up to a factor of two are common. In case of heavy ions such as gold, electronic stopping cross sections predicted by SRIM are asserted to be almost an order of magnitude too high. (authors)

Reciprocity in the electronic stopping of slow ions in matter

Science.gov (United States)

Sigmund, P.

2008-04-01

The principle of reciprocity, i.e., the invariance of the inelastic excitation in ion-atom collisions against interchange of projectile and target, has been applied to the electronic stopping cross section of low-velocity ions and tested empirically on ion-target combinations supported by a more or less adequate amount of experimental data. Reciprocity is well obeyed (within ~10%) for many systems studied, and deviations exceeding ~20% are exceptional. Systematic deviations such as gas-solid or metal-insulator differences have been looked for but not identified on the present basis. A direct consequence of reciprocity is the equivalence of Z1 with Z2 structure for random slowing down. This feature is reasonably well supported empirically for ion-target combinations involving carbon, nitrogen, aluminium and argon. Reciprocity may be utilized as a criterion to reject questionable experimental data. In cases where a certain stopping cross section has not been or cannot be measured, the stopping cross section for the inverted system may be available and serve as a first estimate. It is suggested to build in reciprocity as a fundamental requirement into empirical interpolation schemes directed at the stopping of low-velocity ions. Examination of the SRIM and MSTAR codes reveals cases where reciprocity is obeyed accurately, but deviations of up to a factor of two are common. In case of heavy ions such as gold, electronic stopping cross sections predicted by SRIM are asserted to be almost an order of magnitude too high.

Using Excel's Matrix Operations to Facilitate Reciprocal Cost Allocations

Science.gov (United States)

Leese, Wallace R.; Kizirian, Tim

2009-01-01

The reciprocal method of service department cost allocation requires linear equations to be solved simultaneously. These computations are often so complex as to cause the abandonment of the reciprocal method in favor of the less sophisticated direct or step-down methods. Here is a short example demonstrating how Excel's sometimes unknown matrix…

Training Peer Partners to Use a Speech-Generating Device With Classmates With Autism Spectrum Disorder: Exploring Communication Outcomes Across Preschool Contexts.

Science.gov (United States)

Thiemann-Bourque, Kathy S; McGuff, Sara; Goldstein, Howard

2017-09-18

This study examined effects of a peer-mediated intervention that provided training on the use of a speech-generating device for preschoolers with severe autism spectrum disorder (ASD) and peer partners. Effects were examined using a multiple probe design across 3 children with ASD and limited to no verbal skills. Three peers without disabilities were taught to Stay, Play, and Talk using a GoTalk 4+ (Attainment Company) and were then paired up with a classmate with ASD in classroom social activities. Measures included rates of communication acts, communication mode and function, reciprocity, and engagement with peers. Following peer training, intervention effects were replicated across 3 peers, who all demonstrated an increased level and upward trend in communication acts to their classmates with ASD. Outcomes also revealed moderate intervention effects and increased levels of peer-directed communication for 3 children with ASD in classroom centers. Additional analyses revealed higher rates of communication in the added context of preferred toys and snack. The children with ASD also demonstrated improved communication reciprocity and peer engagement. Results provide preliminary evidence on the benefits of combining peer-mediated and speech-generating device interventions to improve children's communication. Furthermore, it appears that preferred contexts are likely to facilitate greater communication and social engagement with peers.

Using the Preschool Language Scale, Fourth Edition to Characterize Language in Preschoolers with Autism Spectrum Disorders

Science.gov (United States)

Volden, Joanne; Smith, Isabel M.; Szatmari, Peter; Bryson, Susan; Fombonne, Eric; Mirenda, Pat; Roberts, Wendy; Vaillancourt, Tracy; Waddell, Charlotte; Zwaigenbaum, Lonnie; Georgiades, Stelios; Duku, Eric; Thompson, Ann

2011-01-01

Purpose: The Preschool Language Scale, Fourth Edition (PLS-4; Zimmerman, Steiner, & Pond, 2002) was used to examine syntactic and semantic language skills in preschool children with autism spectrum disorders (ASD) to determine its suitability for use with this population. We expected that PLS-4 performance would be better in more…

Construction environment education development activity for children pre-school

OpenAIRE

MA. TRAN THI THUY NGA; MA. PHAM THI YEN

2015-01-01

Education motor development contribute to the comprehensive development of pre-school children. Building educational environment for young athletes develop in pre-school is one of many issues of concern in the current stage of pre-school education in Vietnam.

Universal Preschool Programs and Long-Term Child Outcomes

DEFF Research Database (Denmark)

Dietrichson, Jens; Kristiansen, Ida Lykke; Viinholt Nielsen, Bjørn Christian

2018-01-01

This systematic review included 25 studies using natural experiments to estimate the effects of universal preschool programs for children aged 0-6 years on child outcomes measured from third grade to adulthood. Studies comparing preschool with parental, family, or other informal modes of care...... alternative types of universal preschool programs in terms of long-term outcomes....

Neural precursors of future liking and affective reciprocity.

Science.gov (United States)

Zerubavel, Noam; Hoffman, Mark Anthony; Reich, Adam; Ochsner, Kevin N; Bearman, Peter

2018-04-24

Why do certain group members end up liking each other more than others? How does affective reciprocity arise in human groups? The prediction of interpersonal sentiment has been a long-standing pursuit in the social sciences. We combined fMRI and longitudinal social network data to test whether newly acquainted group members' reward-related neural responses to images of one another's faces predict their future interpersonal sentiment, even many months later. Specifically, we analyze associations between relationship-specific valuation activity and relationship-specific future liking. We found that one's own future (T2) liking of a particular group member is predicted jointly by actor's initial (T1) neural valuation of partner and by that partner's initial (T1) neural valuation of actor. These actor and partner effects exhibited equivalent predictive strength and were robust when statistically controlling for each other, both individuals' initial liking, and other potential drivers of liking. Behavioral findings indicated that liking was initially unreciprocated at T1 yet became strongly reciprocated by T2. The emergence of affective reciprocity was partly explained by the reciprocal pathways linking dyad members' T1 neural data both to their own and to each other's T2 liking outcomes. These findings elucidate interpersonal brain mechanisms that define how we ultimately end up liking particular interaction partners, how group members' initially idiosyncratic sentiments become reciprocated, and more broadly, how dyads evolve. This study advances a flexible framework for researching the neural foundations of interpersonal sentiments and social relations that-conceptually, methodologically, and statistically-emphasizes group members' neural interdependence. Copyright © 2018 the Author(s). Published by PNAS.

Reciprocal Relationships between Math Self-Concept and Math Anxiety

Science.gov (United States)

Ahmed, Wondimu; Minnaert, Alexander; Kuyper, Hans; van der Werf, Greetje

2012-01-01

The present study examined the reciprocal relationships between self-concept and anxiety in mathematics. A sample of 495 grade 7 students (51% girls) completed self-report measures assessing self-concept and anxiety three times in a school year. Structural equation modeling was used to test a cross-lagged panel model of reciprocal effects between…

Direct reciprocity in animals: The roles of bonding and affective processes.

Science.gov (United States)

Freidin, Esteban; Carballo, Fabricio; Bentosela, Mariana

2017-04-01

The presence of direct reciprocity in animals is a debated topic, because, despite its evolutionary plausibility, it is believed to be uncommon. Some authors claim that stable reciprocal exchanges require sophisticated cognition which has acted as a constraint on its evolution across species. In contrast, a more recent trend of research has focused on the possibility that direct reciprocity occurs within long-term bonds and relies on simple as well as more complex affective mechanisms such as emotional book-keeping, rudimentary and higher forms of empathy, and inequity aversion, among others. First, we present evidence supporting the occurrence of long-term reciprocity in the context of existing bonds in social birds and mammals. Second, we discuss the evidence for affective responses which, modulated by bonding, may underlie altruistic behaviours in different species. We conclude that the mechanisms that may underlie reciprocal exchanges are diverse, and that some act in interaction with bonding processes. From simple associative learning in social contexts, through emotional contagion and behavioural mimicry, to empathy and a sense of fairness, widespread and diverse social affective mechanisms may explain why direct reciprocity may not be a rare phenomenon among social vertebrates. © 2015 International Union of Psychological Science.

Synchronized conductivity modulation to realize broadband lossless magnetic-free non-reciprocity.

Science.gov (United States)

Dinc, Tolga; Tymchenko, Mykhailo; Nagulu, Aravind; Sounas, Dimitrios; Alu, Andrea; Krishnaswamy, Harish

2017-10-06

Recent research has explored the spatiotemporal modulation of permittivity to break Lorentz reciprocity in a manner compatible with integrated-circuit fabrication. However, permittivity modulation is inherently weak and accompanied by loss due to carrier injection, particularly at higher frequencies, resulting in large insertion loss, size, and/or narrow operation bandwidths. Here, we show that the presence of absorption in an integrated electronic circuit may be counter-intuitively used to our advantage to realize a new generation of magnet-free non-reciprocal components. We exploit the fact that conductivity in semiconductors provides a modulation index several orders of magnitude larger than permittivity. While directly associated with loss in static systems, we show that properly synchronized conductivity modulation enables loss-free, compact and extremely broadband non-reciprocity. We apply these concepts to obtain a wide range of responses, from isolation to gyration and circulation, and verify our findings by realizing a millimeter-wave (25 GHz) circulator fully integrated in complementary metal-oxide-semiconductor technology.Optical non-reciprocity achieved through refractive index modulation can have its challenges and limitations. Here, Dinc et al. introduce the concept of non-reciprocity based on synchronized spatio-temporal modulation of conductivity to achieve different types of non-reciprocal functionality.

Reciprocal locomotion of dense swimmers in Stokes flow

International Nuclear Information System (INIS)

Gonzalez-Rodriguez, David; Lauga, Eric

2009-01-01

Due to the kinematic reversibility of Stokes flow, a body executing a reciprocal motion (a motion in which the sequence of body configurations remains identical under time reversal) cannot propel itself in a viscous fluid in the limit of negligible inertia; this result is known as Purcell's scallop theorem. In this limit, the Reynolds numbers based on the fluid inertia and on the body inertia are all zero. Previous studies characterized the breakdown of the scallop theorem with fluid inertia. In this paper we show that, even in the absence of fluid inertia, certain dense bodies undergoing reciprocal motion are able to swim. Using Lorentz's reciprocal theorem, we first derive the general differential equations that govern the locomotion kinematics of a dense swimmer. We demonstrate that no reciprocal swimming is possible if the body motion consists only of tangential surface deformation (squirming). We then apply our general formulation to compute the locomotion of four simple swimmers, each with a different spatial asymmetry, that perform normal surface deformations. We show that the resulting swimming speeds (or rotation rates) scale as the first power of a properly defined 'swimmer Reynolds number', demonstrating thereby a continuous breakdown of the scallop theorem with body inertia.

Chimpanzees trust conspecifics to engage in low-cost reciprocity.

Science.gov (United States)

Engelmann, Jan M; Herrmann, Esther; Tomasello, Michael

2015-02-22

Many of humans' most important social interactions rely on trust, including most notably among strangers. But little is known about the evolutionary roots of human trust. We presented chimpanzees (Pan troglodytes) with a modified version of the human trust game--trust in reciprocity--in which subjects could opt either to obtain a small but safe reward on their own or else to send a larger reward to a partner and trust her to reciprocate a part of the reward that she could not access herself. In a series of three studies, we found strong evidence that in interacting with a conspecific, chimpanzees show spontaneous trust in a novel context; flexibly adjust their level of trust to the trustworthiness of their partner and develop patterns of trusting reciprocity over time. At least in some contexts then, trust in reciprocity is not unique to humans, but rather has its evolutionary roots in the social interactions of humans' closest primate relatives. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Modern Social Science Concepts, Proportionate Reciprocity, Modesty, and Democracy

Directory of Open Access Journals (Sweden)

Gerasimos T. SOLDATOS

2014-06-01

Full Text Available Proportionate Reciprocity, Modesty, and Democracy, are the key concepts in Aristotle’s economics of exchange. The following correspondence of these concepts with modern social science may be contemplated: (a Ideally, reciprocal justice in bilateral bargaining to minimize expenditure given utility levels results in Pareto-efficient, envy-free, equitable outcomes. (b Practically, bargaining under the threat or actual recontracting may act as a surrogate of reciprocal justice, leading to an N-person contract topology. (c But, recontracting is subject to practical limitations too, in which case near-reciprocal justice/general equilibrium outcomes may be fostered if, as a surrogate of recontracting, modesty in interaction is exhibited in an evolutionarily-stable-strategy fashion. (d That is, incomplete recontracting amounts to asymmetric agent-type information, which in turn lays the ground for injustices; the same lack of information prevents rectificatory justice from being efficient and hence, modesty can be efficient only if it operates as a social norm and hence, only in a modest polity, which can be no other than democracy.

Preschool Teachers' Use of Music in the Classroom: A Survey of Park District Preschool Programs

Science.gov (United States)

Rajan, Rekha S.

2017-01-01

The purpose of this study was to explore how preschool teachers use music and identify the types of music activities available to children in their classrooms. Preschool teachers (N = 178) at park district programs throughout a large state in the American Midwest responded to an online questionnaire. Although teachers acknowledged using music…

Examining the Predictive Relations between Two Aspects of Self-Regulation and Growth in Preschool Children’s Early Literacy Skills

Science.gov (United States)

Lonigan, Christopher J.; Allan, Darcey M.; Phillips, Beth M.

2016-01-01

There is strong evidence that self-regulatory processes are linked to early academic skills both concurrently and longitudinally. The majority of extant longitudinal studies, however, have been conducted using autoregressive techniques that may not accurately model change across time. The purpose of this study was to examine the unique associations between two components of self-regulation, attention and executive functioning (EF), and growth in early literacy skills over the preschool year using latent-growth-curve analysis. The sample included 1,082 preschool children (M-age = 55.0 months, SD = 3.73). Children completed measures of vocabulary, syntax, phonological awareness, print knowledge, cognitive ability, and self-regulation, and children’s classroom teachers completed a behavior rating measure. To examine the independent relations of the self-regulatory skills and cognitive ability with children’s initial early literacy skills and growth across the preschool year, growth models in which the intercept and slope were simultaneously regressed on each of the predictor variables were examined. Because of the significant relation between intercept and slope for most outcomes, slope was regressed on intercept in the models to allow a determination of direct and indirect effects of the predictors on growth in children’s language and literacy skills across the preschool year. In general, both teacher-rated inattention and directly measured EF were uniquely associated with initial skills level; however, only teacher-rated inattention uniquely predicted growth in early literacy skills. These findings suggest that teacher-ratings of inattention may measure an aspect of self-regulation that is particularly associated with the acquisition of academic skills in early childhood. PMID:27854463

Radiation induced reciprocal translocations and inversions in anopheles albimanus

International Nuclear Information System (INIS)

Kaiser, P.E.; Seawright, J.A.; Benedict, M.Q.; Narang, S.

1982-01-01

Reciprocal translocations and inversions were induced in Anopheles albimanus Wiedemann by irradiation of males with X rays. A total of 1669 sperm were assayed, and 175 new aberrations were identified as follows: 102 reciprocal translocations (67 autosomal and 35 sex-linked), 45 pericentric inversions, and 28 paracentric inversions. Eleven of the translocations were nearly whole-arm interchanges, and these were selected for the construction of 'capture systems' for compound chromosomes. Two double-heterozygous translocation strains and four homozygous translocation strains were established. Anopheles albimanus females were irradiated, and a pseudolinkage scheme involving mutant markers was employed to identify reciprocal translocations. The irradiation of females was very inefficient; only one translocation was recovered from 1080 ova tested

A Journey into Reciprocal Space; A crystallographer's perspective

Science.gov (United States)

Glazer, A. M.

2017-10-01

This book introduces undergraduate and graduate students to a crystallographer's view of real and reciprocal space, a concept that has been of particular use by crystallographers to understand the patterns of spots when x-rays are diffracted by crystals. It then proceeds to develop the concept in a form suitable for physics applications; such as how solid-state physicists use reciprocal space to explain various solid-state properties such as thermal and electrical phenomena.

Preschool Teachers' Attitudes and Beliefs Toward Science

Science.gov (United States)

Lloyd, Sharon Henry

In the United States, a current initiative, Advancing Active STEM Education for Our Youngest Learners, aims to advance science, technology, engineering, and math (STEM) education in early childhood. The purpose of this study was to understand preschool teachers' proficiency with science and address the problem of whether or not science learning opportunities are provided to young children based on teachers' attitudes and beliefs. A theoretical framework for establishing teachers' attitudes toward science developed by van Aalderen-Smeets, van der Molen, and Asma, along with Bandura's theory of self-efficacy were the foundations for this research. Research questions explored preschool teachers' attitudes and beliefs toward science in general and how they differed based on education level and years of preschool teaching experience. Descriptive comparative data were collected from 48 preschool teacher participants using an online format with a self-reported measure and were analyzed using nonparametric tests to describe differences between groups based on identified factors of teacher comfort, child benefit, and challenges. Results indicated that the participants believed that early childhood science is developmentally appropriate and that young children benefit from science instruction through improved school-readiness skills. Preschool teachers with a state credential or an associate's degree and more teaching experience had more teacher comfort toward science based on attitudes and beliefs surveyed. The data indicated participating preschool teachers experienced few challenges in teaching science. The study may support positive social change through increased awareness of strengths and weaknesses of preschool teachers for the development of effective science professional development. Science is a crucial component of school-readiness skills, laying a foundation for success in later grades.

Sex differences in the reciprocal behaviour of children with autism

NARCIS (Netherlands)

Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander

2017-01-01

Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with

Who takes the most revenge? Individual differences in negative reciprocity norm endorsement.

Science.gov (United States)

Eisenberger, Robert; Lynch, Patrick; Aselage, Justin; Rohdieck, Stephanie

2004-06-01

The authors report that beliefs favoring the reciprocation of unfavorable treatment form a unitary factor that is distinct from beliefs favoring the reciprocation of favorable treatment. Individual differences in endorsement of this negative reciprocity norm were related to (a) beliefs that people are generally malevolent; (b) inclination toward anger in everyday life; (c) anger, disagreement, and ridicule directed toward a new acquaintance who treated participants unfavorably; and (d) reduced anxiety, positive emotional engagement, and encouragement of a new acquaintance who treated participants favorably. These findings suggest that individual differences in endorsement of the negative norm of reciprocity influence the extent of vengeance.

A Theory of Sequential Reciprocity

NARCIS (Netherlands)

Dufwenberg, M.; Kirchsteiger, G.

1998-01-01

Many experimental studies indicate that people are motivated by reciprocity. Rabin (1993) develops techniques for incorporating such concerns into game theory and economics. His model, however, does not fare well when applied to situations with an interesting dynamic structure (like many

Group differences in reciprocity, multiplexity and exchange : measures and application

NARCIS (Netherlands)

Agneessens, Filip; Skvoretz, John

Local forces structure social networks. One major and widely researched local force is reciprocity, often assumed to work homogeneously across actors-i.e., all actors are equally subject to the same level of force towards reciprocity. Other local forces, like multiplexity and exchange, are also

Apically extruded debris with reciprocating single-file and full-sequence rotary instrumentation systems.

Science.gov (United States)

Bürklein, Sebastian; Schäfer, Edgar

2012-06-01

The purpose of this in vitro study was to assess the amount of apically extruded debris using rotary and reciprocating nickel-titanium instrumentation systems. Eighty human mandibular central incisors were randomly assigned to 4 groups (n = 20 teeth per group). The root canals were instrumented according to the manufacturers' instructions using the 2 reciprocating single-file systems Reciproc (VDW, Munich, Germany) and WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) and the 2 full-sequence rotary Mtwo (VDW, Munich, Germany) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) instruments. Bidistilled water was used as irrigant. The apically extruded debris was collected in preweighted glass vials using the Myers and Montgomery method. After drying, the mean weight of debris was assessed with a microbalance and statistically analyzed using analysis of variance and the post hoc Student-Newman-Keuls test. The time required to prepare the canals with the different instruments was also recorded. The reciprocating files produced significantly more debris compared with both rotary systems (P rotary instruments (P > .05), the reciprocating single-file system Reciproc produced significantly more debris compared with all other instruments (P Instrumentation was significantly faster using Reciproc than with all other instrument (P rotary instrumentation was associated with less debris extrusion compared with the use of reciprocating single-file systems. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The TORE SUPRA fast reciprocating RF probe

International Nuclear Information System (INIS)

Thomas, C.E. Jr.; Harris, J.H.; Haste, G.R.

1994-01-01

A fast reciprocating ICRF (Ion Cyclotron Range of Frequencies) probe was installed and operated on TORE SUPRA during 1992/1993. The body of the probe was originally used on the ATF experiment at ORNL. The probe was adapted for use on TORE SUPRA, and mounted on one of the two fast reciprocating probe mounts. The probe consists of two orthogonal single-turn wire loops, mounted so that one loop senses toroidal RF magnetic fields and the other senses poloidal RF magnetic fields. The probe began operation in June, 1993. The probe active area is approximately 5 cm long by 2 cm, and the reciprocating mount has a slow stroke (5 cm/sec) of 30 cm by 2 cm, and the reciprocating mount has a slow stroke (5 cm/sec) of 30 cm and a fast stroke (1.5 m/sec) of about 10 cm. The probe was operated at distances from the plasma edge ranging from 30 cm to -5 cm (i.e., inside the last closed flux surface). The probe design, electronics, calibration, data acquisition and data processing are discussed. First data from the probe are presented as a function of ICRF power, distance from the plasma, loop orientation, and other plasma parameters. Initial data shows parametric instabilities do not play an important role for ICRF in the TORE SUPRA edge and scrape-off-layer (SOL) plasmas. Additionally it is observed that the probe signal has little or no dependence on position in the SOL/plasma edge

The Personal Norm of Reciprocity among mental health service users: conceptual development and measurement.

Science.gov (United States)

Matejkowski, Jason; McCarthy, Kevin S; Draine, Jeffrey

2011-01-01

A measure of an individual's level of internalization of the norm of reciprocity may signal exchange preferences and indicate whether "active" or "passive" mental health services are preferable to consumers. We evaluated the psychometric properties of one such measure, the Personal Norm of Reciprocity (PNR) scale. We recruited 70 persons receiving mental health services and 65 comparison participants to complete questionnaires assessing reciprocity tendencies and correlates of mental illness. Two of three subscales of a shortened PNR showed evidence of reliability and validity. Consumers endorsed higher levels of the reciprocity norm than persons not seeking services. Persons in "active" service settings displayed greater rigidity in application of the reciprocity norm than individuals in "passive" service settings or comparison participants. The shortened PNR can be a useful measure of individual reciprocity preferences. Measurement of the internalization of the norm of reciprocity may assist practitioners in identifying what types of services are more likely to retain and benefit mental health service consumers.

Reciprocity-based reasons for benefiting research participants: most fail, the most plausible is problematic.

Science.gov (United States)

Sofaer, Neema

2014-11-01

A common reason for giving research participants post-trial access (PTA) to the trial intervention appeals to reciprocity, the principle, stated most generally, that if one person benefits a second, the second should reciprocate: benefit the first in return. Many authors consider it obvious that reciprocity supports PTA. Yet their reciprocity principles differ, with many authors apparently unaware of alternative versions. This article is the first to gather the range of reciprocity principles. It finds that: (1) most are false. (2) The most plausible principle, which is also problematic, applies only when participants experience significant net risks or burdens. (3) Seldom does reciprocity support PTA for participants or give researchers stronger reason to benefit participants than equally needy non-participants. (4) Reciprocity fails to explain the common view that it is bad when participants in a successful trial have benefited from the trial intervention but lack PTA to it. © 2013 John Wiley & Sons Ltd.

Spatially correlated heterogeneous aspirations to enhance network reciprocity

Science.gov (United States)

Tanimoto, Jun; Nakata, Makoto; Hagishima, Aya; Ikegaya, Naoki

2012-02-01

Perc & Wang demonstrated that aspiring to be the fittest under conditions of pairwise strategy updating enhances network reciprocity in structured populations playing 2×2 Prisoner's Dilemma games (Z. Wang, M. Perc, Aspiring to the fittest and promoted of cooperation in the Prisoner's Dilemma game, Physical Review E 82 (2010) 021115; M. Perc, Z. Wang, Heterogeneous aspiration promotes cooperation in the Prisoner's Dilemma game, PLOS one 5 (12) (2010) e15117). Through numerical simulations, this paper shows that network reciprocity is even greater if heterogeneous aspirations are imposed. We also suggest why heterogeneous aspiration fosters network reciprocity. It distributes strategy updating speed among agents in a manner that fortifies the initially allocated cooperators' clusters against invasion. This finding prompted us to further enhance the usual heterogeneous aspiration cases for heterogeneous network topologies. We find that a negative correlation between degree and aspiration level does extend cooperation among heterogeneously structured agents.

The Principle of Structural Reciprocity

DEFF Research Database (Denmark)

Pugnale, Alberto; Parigi, Dario; Kirkegaard, Poul Henning

2011-01-01

This paper deals with the principle of structural reciprocity, considering its origins in both Occidental and Orient culture and aiming to highlight the definition, main peculiarities and interesting aspects of such concept referring to its application to the world of construction. Issues spannin...

The quadratic reciprocity law a collection of classical proofs

CERN Document Server

Baumgart, Oswald

2015-01-01

This book is the English translation of Baumgart’s thesis on the early proofs of the quadratic reciprocity law (“Über das quadratische Reciprocitätsgesetz. Eine vergleichende Darstellung der Beweise”), first published in 1885. It is divided into two parts. The first part presents a very brief history of the development of number theory up to Legendre, as well as detailed descriptions of several early proofs of the quadratic reciprocity law. The second part highlights Baumgart’s comparisons of the principles behind these proofs. A current list of all known proofs of the quadratic reciprocity law, with complete references, is provided in the appendix. This book will appeal to all readers interested in elementary number theory and the history of number theory.

High-Resolution Reciprocal Space Mapping for Characterizing Deformation Structures

DEFF Research Database (Denmark)

Pantleon, Wolfgang; Wejdemann, Christian; Jakobsen, Bo

2014-01-01

With high-angular resolution three-dimensional X-ray diffraction (3DXRD), quantitative information is gained about dislocation structures in individual grains in the bulk of a macroscopic specimen by acquiring reciprocal space maps. In high-resolution 3D reciprocal space maps of tensile......-deformed copper, individual, almost dislocation-free subgrains are identified from high-intensity peaks and distinguished by their unique combination of orientation and elastic strain; dislocation walls manifest themselves as a smooth cloud of lower intensity. The elastic strain shows only minor variations within...... dynamics is followed in situ during varying loading conditions by reciprocal space mapping: during uninterrupted tensile deformation, formation of subgrains is observed concurrently with broadening of Bragg reflections shortly after the onset of plastic deformation. When the traction is terminated, stress...

Feasibility analysis of reciprocating magnetic heat pumps

Science.gov (United States)

Larson, A. V.; Hartley, J. G.; Shelton, Sam V.; Smith, M. M.

1989-01-01

A reciprocating gadolinium core in a regeneration fluid column in the warm bore of a superconducting solenoidal magnet is considered for magnetic refrigeration in 3.517 MW (1000 ton) applications. A procedure is presented to minimize the amount of superconducting cable needed in the magnet design. Estimated system capital costs for an ideal magnetic refrigerator of this type become comparable to conventional chillers as the frequency of reciprocation approaches 10 Hertz. A 1-D finite difference analysis of a regenerator cycling at 0.027 Hertz is presented which exhibits some of the features seen in the experiments of G. V. Brown.

Gain-loss framing effects in dilemmas of trust and reciprocity

NARCIS (Netherlands)

Evans, A.M.; van Beest, I.

2017-01-01

How do trust and reciprocity decisions change when outcomes are framed in terms of potential losses (vs gains)? In two studies, with 7464 trust decisions from 359 participants and 2723 reciprocity decisions from 221 participants, we find that loss framing increases mean-level trust, but has no

Reciprocity and Dependency Considerations in Adult Donating and Verbal Judgments.

Science.gov (United States)

Peterson, Lizette; McCommis, Bruce

The norms of social responsibility and reciprocity govern altruistic behavior. Children and adults show a consistent developmental trend in comparisons of their responses to positive reciprocal situations and their subsequent altruism. Research indicates, however, that children, given the choice to behaviorally aid a needy individual, choose more…

Neural signatures of trust in reciprocity: A coordinate-based meta-analysis.

Science.gov (United States)

Bellucci, Gabriele; Chernyak, Sergey V; Goodyear, Kimberly; Eickhoff, Simon B; Krueger, Frank

2017-03-01

Trust in reciprocity (TR) is defined as the risky decision to invest valued resources in another party with the hope of mutual benefit. Several fMRI studies have investigated the neural correlates of TR in one-shot and multiround versions of the investment game (IG). However, an overall characterization of the underlying neural networks remains elusive. Here, a coordinate-based meta-analysis was employed (activation likelihood estimation method, 30 articles) to investigate consistent brain activations in each of the IG stages (i.e., the trust, reciprocity and feedback stage). Results showed consistent activations in the anterior insula (AI) during trust decisions in the one-shot IG and decisions to reciprocate in the multiround IG, likely related to representations of aversive feelings. Moreover, decisions to reciprocate also consistently engaged the intraparietal sulcus, probably involved in evaluations of the reciprocity options. On the contrary, trust decisions in the multiround IG consistently activated the ventral striatum, likely associated with reward prediction error signals. Finally, the dorsal striatum was found consistently recruited during the feedback stage of the multiround IG, likely related to reinforcement learning. In conclusion, our results indicate different neural networks underlying trust, reciprocity, and feedback learning. These findings suggest that although decisions to trust and reciprocate may elicit aversive feelings likely evoked by the uncertainty about the decision outcomes and the pressing requirements of social standards, multiple interactions allow people to build interpersonal trust for cooperation via a learning mechanism by which they arguably learn to distinguish trustworthy from untrustworthy partners. Hum Brain Mapp 38:1233-1248, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Towards an understanding of the relative strengths of positive and negative reciprocity

Directory of Open Access Journals (Sweden)

Omar Al-Ubaydli

2010-12-01

Full Text Available Scholars in economics and psychology have created a large literature studying reward, punishment and reciprocity. Labor markets constitute a popular application of this body of work, with particular emphasis on how reciprocity helps regulate workplace relationships where managers are unable to perfectly monitor workers. We study how idiosyncratic features of the labor market (compared to most scenarios in which reciprocity applies affect the nature of worker reciprocity. In particular, we show how having an excess supply of workers (simulating unemployment and managers who can observe the reciprocal behavior of workers and hire/fire them on that basis (simulating the reputational concerns inherent in labor market transactions profoundly alters worker reciprocity. In the absence of reputational concerns, workers tend to reward kind behavior and punish unkind behavior by managers in approximately equal measure. In the presence of reputational concerns, workers exhibit a marked increase (decrease in the propensity to reward kind (punish unkind behavior by managers. We demonstrate how this is a consequence of workers and managers responding to changes in the strategic incentives to reward and punish. %JEL codes: D03, D63, J3, J53

A reciprocity-based formula for the capacitance with quadrupolar electrodes

Energy Technology Data Exchange (ETDEWEB)

Cho, Sungbo [Gachon University of Medicine and Science, Incheon (Korea, Republic of)

2011-11-15

A new capacitance formula for the practical design and characterization of quadrupolar electrode arrays with capacitive structures was derived based on the reciprocal theorem. The reciprocity-based capacitance formula agreed with the empirical equations established to estimate the capacitance of a single strip line or disk electrode compensating for the fringing field effect that occurs at the electrode edge. The reciprocity-based formula was applied to compute the capacitance measurable by using a quadrupolar square electrode array with a symmetric dipole-dipole configuration and was compared with the analytical equation established based on the image method assuming that the electrodes were points. The results showed that the capacitance of the quadrupolar electrodes was determined by the size of the quadrupolar electrodes relative to the separation distance between the electrodes and that the reciprocity-based capacitance formula was in agreement with the established analytical equation if the separated distance between the electrodes relative to the electrode size was large enough.

A reciprocity-based formula for the capacitance with quadrupolar electrodes

International Nuclear Information System (INIS)

Cho, Sungbo

2011-01-01

A new capacitance formula for the practical design and characterization of quadrupolar electrode arrays with capacitive structures was derived based on the reciprocal theorem. The reciprocity-based capacitance formula agreed with the empirical equations established to estimate the capacitance of a single strip line or disk electrode compensating for the fringing field effect that occurs at the electrode edge. The reciprocity-based formula was applied to compute the capacitance measurable by using a quadrupolar square electrode array with a symmetric dipole-dipole configuration and was compared with the analytical equation established based on the image method assuming that the electrodes were points. The results showed that the capacitance of the quadrupolar electrodes was determined by the size of the quadrupolar electrodes relative to the separation distance between the electrodes and that the reciprocity-based capacitance formula was in agreement with the established analytical equation if the separated distance between the electrodes relative to the electrode size was large enough.

Indirection and computer security.

Energy Technology Data Exchange (ETDEWEB)

Berg, Michael J.

2011-09-01

The discipline of computer science is built on indirection. David Wheeler famously said, 'All problems in computer science can be solved by another layer of indirection. But that usually will create another problem'. We propose that every computer security vulnerability is yet another problem created by the indirections in system designs and that focusing on the indirections involved is a better way to design, evaluate, and compare security solutions. We are not proposing that indirection be avoided when solving problems, but that understanding the relationships between indirections and vulnerabilities is key to securing computer systems. Using this perspective, we analyze common vulnerabilities that plague our computer systems, consider the effectiveness of currently available security solutions, and propose several new security solutions.

Effect of direct reciprocity and network structure on continuing prosperity of social networking services.

Science.gov (United States)

Osaka, Kengo; Toriumi, Fujio; Sugawara, Toshihauru

2017-01-01

Social networking services (SNSs) are widely used as communicative tools for a variety of purposes. SNSs rely on the users' individual activities associated with some cost and effort, and thus it is not known why users voluntarily continue to participate in SNSs. Because the structures of SNSs are similar to that of the public goods (PG) game, some studies have focused on why voluntary activities emerge as an optimal strategy by modifying the PG game. However, their models do not include direct reciprocity between users, even though reciprocity is a key mechanism that evolves and sustains cooperation in human society. We developed an abstract SNS model called the reciprocity rewards and meta-rewards games that include direct reciprocity by extending the existing models. Then, we investigated how direct reciprocity in an SNS facilitates cooperation that corresponds to participation in SNS by posting articles and comments and how the structure of the networks of users exerts an influence on the strategies of users using the reciprocity rewards game. We run reciprocity rewards games on various complex networks and an instance network of Facebook and found that two types of stable cooperation emerged. First, reciprocity slightly improves the rate of cooperation in complete graphs but the improvement is insignificant because of the instability of cooperation. However, this instability can be avoided by making two assumptions: high degree of fun, i.e. articles are read with high probability, and different attitudes to reciprocal and non-reciprocal agents. We then propose the concept of half free riders to explain what strategy sustains cooperation-dominant situations. Second, we indicate that a certain WS network structure affects users' optimal strategy and facilitates stable cooperation without any extra assumptions. We give a detailed analysis of the different characteristics of the two types of cooperation-dominant situations and the effect of the memory of

The Discourse of a Preschool Education Curriculum

Directory of Open Access Journals (Sweden)

Lidija Miškeljin

2016-02-01

Full Text Available The paper presents a critical analysis of the discourse of a preschool education curriculum. Its starting point is Foucault’s concept of discourse as language in use, which not only reflects the social order, but also shapes it through a network of conventions, knowledge and practices determining man’s – or, in this case, the reader’s – perception of reality. The analysis is based on identifying the discourse strategies and/or systems of rules laid out in the text The basic principles of the preschool education curriculum for three- to seven-year-old children – model A which make possible certain statements and insights regarding children and thus position the child and the preschool teacher by means of discourse repertoires. This approach helps contextualize the text and leads to an understanding of the basic discourse mechanism involved in the creation of specific versions of preschool education. As discourse analysis itself is related to interpretation and narratology, with the story as a constant, so is this paper a story about a preschool curriculum, for, like any other text, it tells an unfinished story that can yet evolve in different directions.

Assessing Preschool Teachers' Practices to Promote Self-Regulated Learning

Science.gov (United States)

Adagideli, Fahretdin Hasan; Saraç, Seda; Ader, Engin

2015-01-01

Recent research reveals that in preschool years, through pedagogical interventions, preschool teachers can and should promote self-regulated learning. The main aim of this study is to develop a self-report instrument to assess preschool teachers' practices to promote self-regulated learning. A pool of 50 items was recruited through literature…

Provisions for Outdoor Play and Learning in Slovene Preschools

Science.gov (United States)

Kos, Marjanca; Jerman, Janez

2013-01-01

This study examined play and learning in the natural environment and on the playgrounds of Slovene preschools. It included 140 preschool teachers and 264 parents of children who attended preschools in 21 Slovene towns. Data were collected through questionnaires with questions referring to time spent outdoors, children's outdoor activities,…

Lexical and metaphonological abilities in preschoolers with phonological disorders.

Science.gov (United States)

Costa, Ranilde Cristiane Cavalcante; Avila, Clara Regina Brandão de

2010-01-01

lexical and metaphonological abilities of phonologically disordered preschoolers. to investigate the influence of Phonological Disorder on the lexical and metaphonological abilities of a group of preschoolers and the correlation between them. participants were 56 preschoolers - 32 boys and 24 girls - with ages between 4 years and 6 months and 6 years and 11 months, divided into two different groups: the Research Group, composed of 28 preschoolers with Phonological Disorder, and the Control Group, composed of 28 preschoolers with normal speech and no oral speech-related complaints, paired to the research group by gender and age. All of the participants were initially assessed by the ABFW Test - Phonology. After that, they were assessed on their lexical and metaphonological abilities by the ABFW Test - Vocabulary and phonological awareness test: sequential assessment instrument, CONFIAS - identification tasks and, rhyme and alliteration production, respectively. regarding lexical ability, the preschoolers from both groups presented similar behavior. The disordered preschoolers presented the worst performance on the overall analysis of the metaphonological ability. Age had an influence on the performance of lexical ability for both groups and the metaphonological abilities only for the Control Group. Correlations were identified, mostly positive, good to moderate between lexical and metaphonological abilities. the influence of Phonological Disorder may only be observed on the metaphonological performance. Phonological Disorder did not interfere with the development of the lexical ability of this group of preschoolers. Positive correlations were identified between both abilities in the studied age group.

Sorting genomes by reciprocal translocations, insertions, and deletions.

Science.gov (United States)

Qi, Xingqin; Li, Guojun; Li, Shuguang; Xu, Ying

2010-01-01

The problem of sorting by reciprocal translocations (abbreviated as SBT) arises from the field of comparative genomics, which is to find a shortest sequence of reciprocal translocations that transforms one genome Pi into another genome Gamma, with the restriction that Pi and Gamma contain the same genes. SBT has been proved to be polynomial-time solvable, and several polynomial algorithms have been developed. In this paper, we show how to extend Bergeron's SBT algorithm to include insertions and deletions, allowing to compare genomes containing different genes. In particular, if the gene set of Pi is a subset (or superset, respectively) of the gene set of Gamma, we present an approximation algorithm for transforming Pi into Gamma by reciprocal translocations and deletions (insertions, respectively), providing a sorting sequence with length at most OPT + 2, where OPT is the minimum number of translocations and deletions (insertions, respectively) needed to transform Pi into Gamma; if Pi and Gamma have different genes but not containing each other, we give a heuristic to transform Pi into Gamma by a shortest sequence of reciprocal translocations, insertions, and deletions, with bounds for the length of the sorting sequence it outputs. At a conceptual level, there is some similarity between our algorithm and the algorithm developed by El Mabrouk which is used to sort two chromosomes with different gene contents by reversals, insertions, and deletions.

The Situated Nature of Preschool Children's Conflict Strategies

OpenAIRE

Thornberg, Robert

2006-01-01

The purpose of this study was to examine whether the peer conflict strategies of preschool children are situated and therefore vary across different conflict situations. Hypothetical conflict interviews were administered through a series of puppet shows. Participants were 178 preschool children. Results indicate that preschool children's conflict management skills are situated in peer conflict, because their strategies are to a greater or lesser degree influenced by the opponent's strategies....

A survey on parental expectations toward preschool programs

OpenAIRE

菊池, 知美

2009-01-01

The purpose of this study was to investigate what parents expect from preschool programs. Pilot Study tried to construct a scale to measure parental expectations toward preschools. Based on weekly observation of children at a preschool, interviews with their teachers, and open-end questionnaires filled in by mothers, the parental expectations were hypothesized to involve four dimensions of children's competencies: intellectual abilities, good classroom attitude, sociability, and interactions....

[The reciprocity rule in the construction of relationships as the key in relational processes].

Science.gov (United States)

Fenelli, Antonio; Volpi, Cecilia; Guarracino, Emanuele; Galli, Virginia; Esposito, Massimo

2011-01-01

Reciprocity as an expression of the therapist-patient relationship is pointed-out by Mario Reda who refers to Comparetti's studies on the mother-foetus reciprocity, mediated by the so-called "jumps". Reciprocal behaviours are clearly observable during bird and other animal courtship behaviour, whereas in the Sapiens sapiens species, we may observe the establishing of a very complex reciprocity system, which starts with gestures and bodily attitudes, subsequently activating sensory-motor emotional schemata and internal working models, thus enabling the construction of personal meanings. A relationship may result from an encounter provided that "compatible" meanings are constructed in the context of "possible reciprocity" of significant systems. The observation of reciprocity provides a concrete possibility to reduce the risk of absolute subjectivity related to the I or the you, superceding it through the us.

Talking about Service-Learning: Product or Process? Reciprocity or Solidarity?

Science.gov (United States)

Clifford, Joan

2017-01-01

Through an exploration of values of the neoliberal university and critical service-learning, this article explores how associating service-learning with products and relationships based on reciprocity negatively impacts its connection to social justice. By emphasizing the constructs of process and solidarity, instead of products and reciprocity,…

State Authorization Reciprocity Agreement: Participation and Access to Higher Education

Science.gov (United States)

Onwuameze, Nkechi

2017-01-01

The State Authorization Reciprocity Agreement initiative was launched in 2014 to provide a uniform standard for the regulation of distance education across states in the United States. The system established by the National Council for State Authorization Reciprocity Agreement (NC-SARA) allows willing post-secondary institutions to participate…

An Electric Preschool: Pros and Cons.

Science.gov (United States)

Lee, Marjorie W.

An electric preschool is a classroom or center for children 3 to 5 years of age in which the curriculum with its supportive activities, materials, and equipment depends more on technology that is powered by electricity than on manually operated objects. Certainly, preschoolers need stimulating and safe environments managed by adults who allow them…

Reciprocal cooperation in avian mobbing: playing nice pays.

Science.gov (United States)

Wheatcroft, David J; Price, Trevor D

2008-08-01

Unrelated passerine birds often join together while mobbing, a widespread antipredator behavior during which birds harass a predator. Although previous analyses concluded that mobbing could not have evolved via reciprocity, Krams and colleagues' field experiments show that birds preferentially join mobs with neighbors that have aided them previously, suggesting that these birds utilize reciprocity-based strategies involving individual recognition and recollection of previous interactions with others. This implies a level of sophistication in bird communities greater than had previously been realized.

Apically extruded dentin debris by reciprocating single-file and multi-file rotary system.

Science.gov (United States)

De-Deus, Gustavo; Neves, Aline; Silva, Emmanuel João; Mendonça, Thais Accorsi; Lourenço, Caroline; Calixto, Camila; Lima, Edson Jorge Moreira

2015-03-01

This study aims to evaluate the apical extrusion of debris by the two reciprocating single-file systems: WaveOne and Reciproc. Conventional multi-file rotary system was used as a reference for comparison. The hypotheses tested were (i) the reciprocating single-file systems extrude more than conventional multi-file rotary system and (ii) the reciprocating single-file systems extrude similar amounts of dentin debris. After solid selection criteria, 80 mesial roots of lower molars were included in the present study. The use of four different instrumentation techniques resulted in four groups (n = 20): G1 (hand-file technique), G2 (ProTaper), G3 (WaveOne), and G4 (Reciproc). The apparatus used to evaluate the collection of apically extruded debris was typical double-chamber collector. Statistical analysis was performed for multiple comparisons. No significant difference was found in the amount of the debris extruded between the two reciprocating systems. In contrast, conventional multi-file rotary system group extruded significantly more debris than both reciprocating groups. Hand instrumentation group extruded significantly more debris than all other groups. The present results yielded favorable input for both reciprocation single-file systems, inasmuch as they showed an improved control of apically extruded debris. Apical extrusion of debris has been studied extensively because of its clinical relevance, particularly since it may cause flare-ups, originated by the introduction of bacteria, pulpal tissue, and irrigating solutions into the periapical tissues.

Mathematics and Science Learning Opportunities in Preschool Classrooms

Science.gov (United States)

Piasta, Shayne B.; Pelatti, Christina Yeager; Miller, Heather Lynnine

2014-01-01

Research findings The present study observed and coded instruction in 65 preschool classrooms to examine (a) overall amounts and (b) types of mathematics and science learning opportunities experienced by preschool children as well as (c) the extent to which these opportunities were associated with classroom and program characteristics. Results indicated that children were afforded an average of 24 and 26 minutes of mathematics and science learning opportunities, respectively, corresponding to spending approximately 25% of total instructional time in each domain. Considerable variability existed, however, in the amounts and types of mathematics and science opportunities provided to children in their classrooms; to some extent, this variability was associated with teachers’ years of experience, teachers’ levels of education, and the socioeconomic status of children served in the program. Practice/policy Although results suggest greater integration of mathematics and science in preschool classrooms than previously established, there was considerable diversity in the amounts and types of learning opportunities provided in preschool classrooms. Affording mathematics and science experiences to all preschool children, as outlined in professional and state standards, may require additional professional development aimed at increasing preschool teachers’ understanding and implementation of learning opportunities in these two domains in their classrooms. PMID:25489205

The cost of community-managed viral respiratory illnesses in a cohort of healthy preschool-aged children

Directory of Open Access Journals (Sweden)

Allen Kelly M

2008-01-01

Full Text Available Abstract Background Acute respiratory illnesses (ARIs during childhood are often caused by respiratory viruses, result in significant morbidity, and have associated costs for families and society. Despite their ubiquity, there is a lack of interdisciplinary epidemiologic and economic research that has collected primary impact data, particularly associated with indirect costs, from families during ARIs in children. Methods We conducted a 12-month cohort study in 234 preschool children with impact diary recording and PCR testing of nose-throat swabs for viruses during an ARI. We used applied values to estimate a virus-specific mean cost of ARIs. Results Impact diaries were available for 72% (523/725 of community-managed illnesses between January 2003 and January 2004. The mean cost of ARIs was AU$309 (95% confidence interval $263 to $354. Influenza illnesses had a mean cost of $904, compared with RSV, $304, the next most expensive single-virus illness, although confidence intervals overlapped. Mean carer time away from usual activity per day was two hours for influenza ARIs and between 30 and 45 minutes for all other ARI categories. Conclusion From a societal perspective, community-managed ARIs are a significant cost burden on families and society. The point estimate of the mean cost of community-managed influenza illnesses in healthy preschool aged children is three times greater than those illnesses caused by RSV and other respiratory viruses. Indirect costs, particularly carer time away from usual activity, are the key cost drivers for ARIs in children. The use of parent-collected specimens may enhance ARI surveillance and reduce any potential Hawthorne effect caused by compliance with study procedures. These findings reinforce the need for further integrated epidemiologic and economic research of ARIs in children to allow for comprehensive cost-effectiveness assessments of preventive and therapeutic options.

Calibration of photographic and spectroscopic films. 1: Film batch variations of reciprocity failure in IIaO film. 2: Thermal and aging effects in relationship to reciprocity failure. 3: Shifting of reciprocity failure points as a function of thermal and aging effects. Semiannual report, December 1986

International Nuclear Information System (INIS)

Peters, K.A.; Atkinson, P.F.; Hammond, E.C. Jr.

1986-01-01

Reciprocity failure was examined for IIaO spectroscopic film. Three separate experiments were performed in order to study film batch variations, thermal and aging effects in relationship to reciprocity failure, and shifting of reciprocity failure points as a function of thermal and aging effects. The failure was examined over ranges of time between 5 and 60 seconds. The variation to illuminance was obtained by using thirty neutral density filters. A standard sensitometer device imprinted the wedge pattern on the film as exposure time was subjected to variation. The results indicate that film batch differences, temperature, and aging play an important role in reciprocity failure of IIaO spectroscopic film. A shifting of the failure points was also observed in various batches of film

76 FR 12923 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

Science.gov (United States)

2011-03-09

... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... pollutants for existing stationary spark ignition reciprocating internal combustion engines. The final rule... reciprocating internal combustion generation, engine. transmission, or distribution. 622110 Medical and surgical...

75 FR 51569 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

Science.gov (United States)

2010-08-20

... Air Pollutants for Reciprocating Internal Combustion Engines; Final Rule #0;#0;Federal Register / Vol... for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines AGENCY: Environmental... hazardous air pollutants for existing stationary spark ignition reciprocating internal combustion engines...

Magneto-optical non-reciprocal devices in silicon photonics

Directory of Open Access Journals (Sweden)

Yuya Shoji

2014-01-01

Full Text Available Silicon waveguide optical non-reciprocal devices based on the magneto-optical effect are reviewed. The non-reciprocal phase shift caused by the first-order magneto-optical effect is effective in realizing optical non-reciprocal devices in silicon waveguide platforms. In a silicon-on-insulator waveguide, the low refractive index of the buried oxide layer enhances the magneto-optical phase shift, which reduces the device footprints. A surface activated direct bonding technique was developed to integrate a magneto-optical garnet crystal on the silicon waveguides. A silicon waveguide optical isolator based on the magneto-optical phase shift was demonstrated with an optical isolation of 30 dB and insertion loss of 13 dB at a wavelength of 1548 nm. Furthermore, a four port optical circulator was demonstrated with maximum isolations of 15.3 and 9.3 dB in cross and bar ports, respectively, at a wavelength of 1531 nm.

Propagation of Economic Inequality Through Reciprocity and Reputation.

Science.gov (United States)

Hackel, Leor M; Zaki, Jamil

2018-04-01

Reciprocity and reputation are powerful tools for encouraging cooperation on a broad scale. Here, we highlight a potential side effect of these social phenomena: exacerbating economic inequality. In two novel economic games, we manipulated the amount of money with which participants were endowed and then gave them the opportunity to share resources with others. We found that people reciprocated more toward higher-wealth givers, compared with lower-wealth givers, even when those givers were equally generous. Wealthier givers also achieved better reputations than less wealthy ones and therefore received more investments in a social marketplace. These discrepancies were well described by a formal model of reinforcement learning: Individuals who weighted monetary outcomes, rather than generosity, when learning about interlocutors also most strongly helped wealthier individuals. This work demonstrates that reciprocity and reputation-although globally increasing prosociality-can widen wealth gaps and provides a precise account of how inequality grows through social processes.

Relational Aggression in Children with Preschool-Onset Psychiatric Disorders

Science.gov (United States)

Belden, Andy C.; Gaffrey, Michael S.; Luby, Joan L.

2012-01-01

Objective: The role of preschool-onset (PO) psychiatric disorders as correlates and/or risk factors for relational aggression during kindergarten or first grade was tested in a sample of 146 preschool-age children (age 3 to 5.11 years). Method: Axis-I diagnoses and symptom scores were derived using the Preschool Age Psychiatric Assessment.…

Thermodynamic Analysis of an Irreversible Maisotsenko Reciprocating Brayton Cycle

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Fuli Zhu

2018-03-01

Full Text Available An irreversible Maisotsenko reciprocating Brayton cycle (MRBC model is established using the finite time thermodynamic (FTT theory and taking the heat transfer loss (HTL, piston friction loss (PFL, and internal irreversible losses (IILs into consideration in this paper. A calculation flowchart of the power output (P and efficiency (η of the cycle is provided, and the effects of the mass flow rate (MFR of the injection of water to the cycle and some other design parameters on the performance of cycle are analyzed by detailed numerical examples. Furthermore, the superiority of irreversible MRBC is verified as the cycle and is compared with the traditional irreversible reciprocating Brayton cycle (RBC. The results can provide certain theoretical guiding significance for the optimal design of practical Maisotsenko reciprocating gas turbine plants.

Social evolution: reciprocity there is.

Science.gov (United States)

Taborsky, Michael

2013-06-03

The theory of cooperation predicts that altruism can be established by reciprocity, yet empirical evidence from nature is contentious. Increasingly though, experimental results from social vertebrates challenge the nearly exclusive explanatory power of relatedness for the evolution of cooperation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Correlates of adiposity among Latino preschool children

Science.gov (United States)

Childhood obesity is at record high levels in the US and disproportionately affects Latino children; however, studies examining Latino preschool children's obesity-related risk factors are sparse. This study determined correlates of Latino preschoolers' (ages 3-5 years) adiposity to inform future ob...

Effects of Enrichment Preschooling at Bourke: A Further Follow-up Study

Science.gov (United States)

De Lacey, P. R.; Nurcombe, B.

1977-01-01

As a test of the persistence of the effects of enrichment preschooling, and as a further stage of the evaluation of the Bourke preschool in New South Wales, 96 Aboriginal and white children, preschooled and non-preschooled, were given a battery of tests in 1974 measuring verbal intelligence, language development and classificatory skills.…

Noise and stress effects on preschool personnel

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Fredrik Sjödin

2012-01-01

Full Text Available The aim of the study was to analyze the presence of stress-related health problems among preschool employees and the way in which these reactions are related to noise and other work parameters. The investigation included 101 employees at 17 preschools in Umeå County, located in northern Sweden. Individual noise recordings and recordings in dining rooms and play halls were made at two departments from each preschool. The adverse effects on the employees were analyzed by use of different validated questionnaires and by saliva cortisol samples. Stress and energy output were pronounced among the employees, and about 30% of the staff experienced strong burnout syndromes. Mental recovery after work was low, indicated by remaining high levels of stress after work. The burnout symptoms were associated with reduced sleep quality and morning sleepiness. Cortisol levels supported the conclusion about pronounced daily stress levels of the preschool employees.

Reciprocal Learning: One Teacher's Narrative

Institute of Scientific and Technical Information of China (English)

Adrienne RIGLER

2017-01-01

This paper is a personal narrative from the perspective of one teacher in Toronto who participated in the Canada-China Reciprocal Learning in Teacher Education and School Education Partnership Grant Project.I took part in a Sister School partnership between 2013 and 2017.Over the four years,I came to understand relationships in an international professional learning community.Participating in the project gave me the benefit of seeing my practice through an international lens.For my students,it offered a global citizenship experience.Although there are numerous professional development opportunities in Toronto,this partnership extends beyond a lunch and learn,or a full day professional learning.The commitment to my partners has fueled my desire to incorporate new teaching ideas and has required ongoing reflection on my own teaching practice.In this article,I will explain some of the challenges,stages of development,reciprocal learning,and implications for future international professional learning communities.

Difference in children's gross motor skills between two types of preschools.

Science.gov (United States)

Chow, Bik C; Louie, Lobo H T

2013-02-01

The purpose of this study was to assess the influence of preschool type (public vs private) on motor skill performance in 239 (121 boys, 118 girls) preschool children ages 3 to 6.5 yr. Preschoolers were tested on 12 fundamental motor skills from the Test of Gross Motor Development-Second Edition and 11 anthropometrics (body height, weight, Body Mass Index, waist and hip girths, and body segment lengths). Analysis of variance controlled for anthropometrics and age indicated that children from private preschools performed better on locomotor skills than those from public preschools. However, no difference was found in object control skills. The results suggest that performance of locomotor skills by preschool children is affected by their schools' physical environment.

Sex Differences in the Reciprocal Behaviour of Children with Autism

Science.gov (United States)

Backer van Ommeren, Tineke; Koot, Hans M.; Scheeren, Anke M.; Begeer, Sander

2017-01-01

Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in…

Measurements of reciprocity law failure in green-sensitive X-ray films.

Science.gov (United States)

Arnold, B A; Eisenberg, H; Bjärngard, B E

1978-02-01

Reciprocity law failure was measured for four brands of medical x-ray films exposed with intensifying screens. Three of the films are green light-sensitized for use in combination with green light-emitting rare-earth screens. These films showed larger reciprocity failure effects than one conventional blue-sensitive film, Dupont Cronex-2. Development conditions had a small effect on reciprocity failure. As part of the investigation, a detector was constructed with a response that accurately monitors the light emission from the double screen-cassette combination over a wide range of x-ray photon energies.

Parental knowledge of pre-school child oral health.

Science.gov (United States)

Prabhu, Anand; Rao, Arun Prasad; Reddy, Venugopal; Ahamed, Syed Shaheed; Muhammad, Shameer; Thayumanavan, Shanmugam

2013-10-01

The dental health of preschool children has extensive implications on the oral heath of the individual as he grows into an adult. Parents/guardians of preschool children play a central role in enforcing proper oral hygiene and preventive regime in these children. This study was conducted with the aim of describing the views of parents/guardians about the dental health of pre-school children. Response was obtained on a 21 point questionnaire from randomly visiting parents of the outpatient section of Rajah Muthiah dental college and Hospital, Annamalainagar, India. The findings of the present study point towards poor awareness among the parents/guardians of preschool children, pertaining to their childs' oral health and this could directly translate to poor oral health among the children in this area.

Trust, Reciprocity and Institutional Design: Lessons from Behavioural Economics

OpenAIRE

Pelligra, Vittorio

2006-01-01

Trust and reciprocity are the bond of society (Locke), but economic agents are both self-interested and intrinsically untrustworthy. These assumptions impair severely economists' accounts of social relationships. The paper examines strategies to escape this paradox by enlarging our conception of rationality: the assumptions of self-interest and consequentialism are critically discussed as well as relational behavioural principles (e.g. trust and reciprocity). The implications of this enlarged...

Language Learning in Outdoor Environments: Perspectives of preschool staff

Directory of Open Access Journals (Sweden)

Martina Norling

2015-03-01

Full Text Available Language environment is highlighted as an important area in the early childhood education sector. The term language environment refers to language-promoting aspects of education, such as preschool staff’s use of verbal language in interacting with the children. There is a lack of research about language learning in outdoor environments; thus children’s language learning is mostly based on the indoor physical environment. The aim of this study is therefore to explore, analyse, and describe how preschool staff perceive language learning in outdoor environments. The data consists of focus-group interviews with 165 preschool staff members, conducted in three cities in Sweden. The study is meaningful, thus results contribute knowledge regarding preschool staffs’ understandings of language learning in outdoor environments and develop insights to help preschool staff stimulate children’s language learning in outdoor environments.

General practitioners' perceptions of the stigma of dementia and the role of reciprocity.

Science.gov (United States)

Gove, Dianne; Small, Neil; Downs, Murna; Vernooij-Dassen, Myrra

2017-10-01

A qualitative exploration of the stigma of dementia reported that general practitioners described lack of reciprocity as one way in which people with dementia are perceived within society. This was closely linked to their perception of dementia as a stigma. In this article, we explore whether general practitioners perceive people with dementia as lacking reciprocity and, if so, if this is linked with societal opinions about dementia as a stigma. The implications of both perceptions of people with dementia failing to reciprocate and of stigma for timely diagnosis are explored. Our approach is to follow the thread of reciprocity in the data from our initial study. In this follow-up study, general practitioners' perceptions of societal views of people with dementia included a perception of a lack of reciprocity specifically linked with; failing to respond to human contact, the absence of an appropriate return on social investment and failing to contribute to, or being a burden on, society. General practitioners reported a link between societal perceptions of lack of reciprocity and stereotypes about advanced dementia, difficulties communicating with people with dementia, and lack of opportunities for people with dementia to reciprocate. General practitioners occupy a key position, they can challenge stereotypes and, with support and targeted training about communicating with people living with dementia, can emphasize the ways in which people with dementia can communicate, thereby enhancing their potential to reciprocate. Such changes have implications for improved care and quality of life through the continued maintenance of social inclusion and perceptions of personhood.

A DISCUSSIN OVER RECIPROCITY PRINCIPLE’S AFFECT ON SOCIAL CAPITAL’S PROLIFICACY

OpenAIRE

Mustafa Latif Emek

2014-01-01

In this study two concepts, social capital and reciprocity principles, have been introduced and their reciprocal relationship and affects also been discussed. Social Capital, an indispensable notion for the development of society from all aspects has a close relationship with reciprocity principle which regulates and forms relationship webs. In this study we firstly examined both from emergence point and sources of social capital concept which can also be entitled as social webs. Afterward...

Applying a Socioecological Model to Understand Preschool Children's Sedentary Behaviors from the Viewpoints of Parents and Preschool Personnel

Science.gov (United States)

Määttä, Suvi; Ray, Carola; Roos, Gun; Roos, Eva

2016-01-01

This study explored parents' and preschool personnel's opinions on factors influencing 3-5-year-old children's sedentary behaviors by applying the socioecological model. Four focus group interviews with preschool personnel (N = 14) and six interviews with parents (N = 17) were conducted in autumn 2014. Two researchers independently analyzed the…

Developing preschool children social aptitudes

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Ana Teresa Brás

2012-12-01

Full Text Available The kindergarten teachers must be aware of the importance of the acquisition of social skills for children, with a view to appropriate adaptation and overcoming the various challenges that will have those throughout existence. This article is the presentation of a research work within the pre-school educational context, in the field of ʻSocial and Personal Educationʼ which may lead to improved social skills within the group of children. In order to accomplish this, after the teaching training with the pre-school class which focussed on the acquisition of social competence, an assessment of the modified social skills within the class was carried out. These activities were included in the preschool lesson planning during the ʻSupervised Teaching Practiceʼ. They were developed based on childrenʼs daily life situations, focussing mainly on using games in the learning contexts. The aim of these games was to motivate and involve the children in order to enhance their balanced social development. The results obtained suggest that the introduction of this type of learning activities may be an asset in Pre-school Education because they develop both childrenʼs social skills and social competence. Moreover, this type of learning activities may also lead to changes in childrenʼs social interaction with both adults and their peers which may favour pro social behaviour.

Unilateral or Reciprocal Climate Policy? Experimental Evidence from China

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Thomas Bernauer

2016-09-01

Full Text Available The traditional political economy account of global climate change governance directs our attention to fundamental collective action problems associated with global public goods provision, resulting from positive or negative externalities as well as freeriding. The governance architecture of the 1997 Kyoto Protocol uses the traditional approaches of international diplomacy for addressing such challenges: legally binding commitments based on principles of reciprocity and (fair cost/burden sharing via formalized carbon-budgeting. Yet, the 2015 Paris Agreement has essentially abandoned this approach, as it now operates on the basis of internationally coordinated and monitored unilateralism. On the presumption that public opinion matters for government policy, we examine how citizens view this shift in climate policy from reciprocity to unilateralism, after many years of exposure to strong reciprocity rhetoric by governments and stakeholders. To that end, we fielded a survey experiment in China, the world’s largest greenhouse gas (GHG emitter. The results show that there is, perhaps surprisingly, strong and robust public support for unilateral, non-reciprocal climate policy. To the extent China is interested in pushing ahead with ambitious and thus costly GHG reduction policies, our results suggest that China can leverage segments of public support in order to overcome domestic obstacles to GHG mitigation policies.

Coaction versus reciprocity in continuous-time models of cooperation.

Science.gov (United States)

van Doorn, G Sander; Riebli, Thomas; Taborsky, Michael

2014-09-07

Cooperating animals frequently show closely coordinated behaviours organized by a continuous flow of information between interacting partners. Such real-time coaction is not captured by the iterated prisoner's dilemma and other discrete-time reciprocal cooperation games, which inherently feature a delay in information exchange. Here, we study the evolution of cooperation when individuals can dynamically respond to each other's actions. We develop continuous-time analogues of iterated-game models and describe their dynamics in terms of two variables, the propensity of individuals to initiate cooperation (altruism) and their tendency to mirror their partner's actions (coordination). These components of cooperation stabilize at an evolutionary equilibrium or show oscillations, depending on the chosen payoff parameters. Unlike reciprocal altruism, cooperation by coaction does not require that those willing to initiate cooperation pay in advance for uncertain future benefits. Correspondingly, we show that introducing a delay to information transfer between players is equivalent to increasing the cost of cooperation. Cooperative coaction can therefore evolve much more easily than reciprocal cooperation. When delays entirely prevent coordination, we recover results from the discrete-time alternating prisoner's dilemma, indicating that coaction and reciprocity are connected by a continuum of opportunities for real-time information exchange. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sustaining Preschoolers' Engagement during Interactive Writing Lessons

Science.gov (United States)

Hall, Anna H.

2016-01-01

Interactive writing is a developmentally appropriate activity used to enhance children's literacy development in the preschool setting. This article describes the unique needs of preschoolers as emerging writers, including their developing fine motor skills, early literacy skills, and social skills related to group writing. Strategies are provided…

Relational Aggression in Children with Preschool Onset (PO) Psychiatric Disorders

Science.gov (United States)

Belden, Andy C.; Gaffrey, Michael S.; Luby, Joan L.

2012-01-01

Objective The role of preschool onset (PO) psychiatric disorders as correlates and/or risk factors for relational aggression during kindergarten or 1st grade was tested in a sample of N = 146 preschool-age children (3 to 5.11). Method Axis-I diagnoses and symptom scores were derived using the Preschool Age Psychiatric Assessment. Children’s roles in relational aggression as aggressor, victim, aggressive-victim, or non-aggressor/non-victim were determined at preschool and again 24 months later at elementary school entry. Results Preschoolers diagnosed with PO-psychiatric disorders were 3 times as likely as the healthy preschoolers to be classified aggressors, victims, or aggressive-victims. Children diagnosed with PO-disruptive, depressive, and/or anxiety disorders were at least 6 times as likely as children without PO-psychiatric disorders to become aggressive-victims during elementary school after covarying for other key risk factors. Conclusions Findings suggested that PO-psychiatric disorders differentiated preschool and school-age children’s roles in relational aggression based on teacher-report. Recommendations for future research and preventative intervention aimed at minimizing the development of relational aggression in early childhood by identifying and targeting PO-psychiatric disorders are made. PMID:22917202

Fairness and Reciprocity in the Hawk-Dove Game

DEFF Research Database (Denmark)

Poulsen, Anders; Neugebauer, Tibor; Schram, Arthur

2002-01-01

We study fairness and reciprocity in a Hawk-Dove game, using an experimental approach. This allows us to test various models in one framework. We observe a large extent of selfish and rational behavior. Our results are inconsistent with leading models in this field.......We study fairness and reciprocity in a Hawk-Dove game, using an experimental approach. This allows us to test various models in one framework. We observe a large extent of selfish and rational behavior. Our results are inconsistent with leading models in this field....

Acquiring the Language of Learning: The Performance of Hawaiian Preschool Children on the Preschool Language Assessment Instrument (PLAI).

Science.gov (United States)

Martini, Mary

The Preschool Language Assessment Instrument (PLAI) was designed as a diagnostic tool for 3- to 6-year-old children to assess children's abilities to use language to solve thinking problems typically posed by teachers. The PLAI was developed after observing middle-class teachers in preschool classrooms encourage children to use language in…

Thought Disorder in Preschool Children with Attention Deficit/Hyperactivity Disorder (ADHD).

Science.gov (United States)

Hutchison, Amanda K; Kelsay, Kimberly; Talmi, Ayelet; Noonan, Kate; Ross, Randal G

2016-08-01

Preschool identification of and intervention for psychiatric symptoms has the potential for lifelong benefits. However, preschool identification of thought disorder, a symptom associated with long term risk for social and cognitive dysfunction, has received little attention with previous work limited to examining preschoolers with severe emotional and behavioral dysregulation. Using story-stem methodology, 12 children with ADHD and 12 children without ADHD, ages 4.0-6.0 years were evaluated for thought disorder. Thought disorder was reliably assessed (Cronbach's alpha = .958). Children with ADHD were significantly more likely than children without ADHD to exhibit thought disorder (75 vs 25 %; Fischer's Exact Test = .0391). Thought disorder can be reliably assessed in preschool children and is present in preschool children with psychiatric illness including preschool children with ADHD. Thought disorder may be identifiable in preschool years across a broad range of psychiatric illnesses and thus may be an appropriate target of intervention.

Management of Common Resources and Reciprocity: the contributions of Elinor Ostrom to the Debate

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Eric Sabourin

2010-12-01

Full Text Available This paper analyzes the importance of reciprocity in the processes and procedures recorded in the management of common resources. It examines first the role that E. Ostrom attributes to the norm of reciprocity in her approach to common property resources. A second part interprets economic and social relations in the management of common resources as seen by economic anthropology’s theory of reciprocity. Finally, the conclusion attempts to establish a dialogue between Ostrom’s proposals and the theory of reciprocity.

A reciprocidade nos contratos: uma análise expressivista Contractual reciprocity: an expressivist analysis

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Leandro Martins Zanitelli

2011-06-01

regulation of contractual activity, makes clear its adhesion to the value of reciprocity as equality in exchange or denying of exploitation of one of the parties by the other. The paper argues that the legal expression of the value of reciprocity - which may take place through either a general principle of contractual equality or more specific requirements, as such that of complying with the mean price (or “market price” or that of not establishing certain clauses - is important for two kinds of reasons. first, the expression by the law of the value of reciprocity should be deemed important because the expressive content of the law is intrinsically important. in the case of reciprocity, it is argued that the law, as it manifests the wish that there be some correspondence between the sacrifice made and the advantage obtained by each party, ends up proclaiming, indirectly, The more basic values of equality and fraternity. Second, the legal expression of the value of reciprocity is important in face of its consequences. These consequences are not circumscribed to the ones coming from limits imposed to the freedom of the contractual parties or to the refusal of the courts to enforce unfair contracts, since the legal endorsement of the value of reciprocity may influence the reasons for acting of the contractual parties. As a result, instead of acting only in order to maximize her own gain, each party may include the protection of the interests of the other one among the reasons of her decisions. This paper was organized as follows. After the introduction, which contains some brief remarks on legal expressivism, part II offers a broad definition and some particular conceptions of contractual reciprocity. About each one of these conceptions, some difficulties or inconveniences, which are mostly tied to the attempt of imposing reciprocity through the restrictions of the legal efficacy of voluntarily made agreements, are referred to. Part III is dedicated to two forms of

Reciprocity and Humility in Wonderland

Science.gov (United States)

Harry, Beth

2011-01-01

This article supports the perspective of Jan Valle regarding the importance of recognizing the subjectivity inherent in decisions about Learning Disabilities. The author argues that the perspectives of both parents and professionals are informed by subjective judgments that must be taken into account in decision making. A reciprocal approach to…

METHODIC OF DEVELOPMENT OF MOTOR GIFTEDNESS OF PRESCHOOL CHILDREN

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Fedorova Svetlana Yurievna

2013-04-01

Full Text Available Education and training of gifted children today appropriate to consider as an important strategic task of modern society. In this context, the purpose of research is the development motor giftedness, which is particularly relevant at the stage of pre-school education, which is caused by age-preschoolers. Preschoolers' motor giftedness is considered by the author as developing integrated quality, including psychomotor skills, inclinations, increased motivation for motor activity. In the process of study the following methods are used: the study and analysis of the scientific and methodological literature on studies, questioning, interview, testing of physical fitness, statistical data processing. The result of research work is methodic of development of motor giftedness on physical education in preschool. The author's methodic consists of four steps: diagnostic, prognostic, practice and activity, social and pedagogical. Each step determines the inclusion of preschool children in sports and developing environment that meets his or her abilities and needs through the creation of certain social and educational conditions. The area of using results of the author's methodic is preschool and the system of improvement professional skill of teachers.

Reciprocity: A Predictor of Mental Health and Continuity in Elderly People's Relationships? A Review

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Live Fyrand

2010-01-01

Full Text Available Many studies have demonstrated that social relationships confer mental health benefits. This paper aims to identify whether and how reciprocity in social relationships predicts or is associated with mental health benefits as well as with continuity in elderly people's social relationships. The studies reviewed in this paper show that, among elders, being in a balanced or underbenefited reciprocal position predicts better mental health and life quality than being in an overbenefited position. Throughout the course of life, reciprocity evens out present and earlier reciprocal imbalances, securing continuity in close relationships—particularly between spouses and between elderly parents and adult children. In friendships, securing continuity seems to be based on the maintenance of independence based on balanced reciprocal relations, making these relationships more vulnerable. Due to the problems of conceptualization and measurement in the reviewed studies, one should be cautious in stating a final conclusion that the reciprocity norm has a universal positive effect on mental health and continuity in elderly people's relationships.

Reciprocity: A Predictor of Mental Health and Continuity in Elderly People's Relationships? A Review.

Science.gov (United States)

Fyrand, Live

2010-01-01

Many studies have demonstrated that social relationships confer mental health benefits. This paper aims to identify whether and how reciprocity in social relationships predicts or is associated with mental health benefits as well as with continuity in elderly people's social relationships. The studies reviewed in this paper show that, among elders, being in a balanced or underbenefited reciprocal position predicts better mental health and life quality than being in an overbenefited position. Throughout the course of life, reciprocity evens out present and earlier reciprocal imbalances, securing continuity in close relationships-particularly between spouses and between elderly parents and adult children. In friendships, securing continuity seems to be based on the maintenance of independence based on balanced reciprocal relations, making these relationships more vulnerable. Due to the problems of conceptualization and measurement in the reviewed studies, one should be cautious in stating a final conclusion that the reciprocity norm has a universal positive effect on mental health and continuity in elderly people's relationships.

Preschool Teaching Staff's Opinions on the Importance of Preschool Curricular Fields of Activities, Art Genres and Visual Arts Fields

Science.gov (United States)

Zupancic, Tomaž; Cagran, Branka; Mulej, Matjaž

2015-01-01

This article presents preschool teachers' and assistant teachers' opinions on the importance of selected fields of educational work in kindergartens. The article first highlights the importance of activities expressing artistic creativity within modern curriculums. Then, it presents an empirical study that examines the preschool teachers' and…

Preschool Teachers' Language Use in Sociodramatic Play

Science.gov (United States)

Meacham, Sohyun

2013-01-01

Preschool teachers' language use has been described in recent research, as preschoolers' language development is found to be an important preparation for later reading development. Based on existing research on teachers' language use in sociodramatic play, however, it is still unclear how teachers use their language specifically in sociodramatic…

A Study of Music Instruction in Preschool Education Training : Part II

OpenAIRE

丸山, 京子; Kyoko, Maruyama

2001-01-01

Last year, the author and others studied music instruction in preschool education training. In that paper, we learn what was required to become successful preschool teacher and the relationship between kindergarten children and preschool education major students. Based on the results of that study, the author has come to realize the importance of music instruction and music performance in childhood development in the preschool curriculum.

Challenges to preschool teachers in learner\\'s acquisition of English ...

African Journals Online (AJOL)

knowledge of English, are enrolled in English preschools. Preschool teachers have the demanding task of preparing these multilingual preschoolers for formal schooling in English, and, in addition, are pressurised by parents or caregivers who expect their children to be fluent in English by the time they enter primary school.

Reduced reciprocal giving in social anxiety - Evidence from the Trust Game.

Science.gov (United States)

Anderl, Christine; Steil, Regina; Hahn, Tim; Hitzeroth, Patricia; Reif, Andreas; Windmann, Sabine

2018-06-01

Social anxiety is known to impair interpersonal relationships. These impairments are thought to partly arise from difficulties to engage in affiliative interactions with others, such as sharing favors or reciprocating prosocial acts. Here, we examined whether individuals high compared to low in social anxiety differ in giving towards strangers in an economic game paradigm. One hundred and twenty seven non-clinical participants who had been pre-screened to be either particularly high or low in social anxiety played an incentivized Trust Game to assess trustful and reciprocal giving towards strangers in addition to providing information on real life interpersonal functioning (perceived social support and attachment style). We found that reciprocal, but not trustful giving, was significantly decreased among highly socially anxious individuals. Both social anxiety and reciprocal giving furthermore showed significant associations with self-reported real life interpersonal functioning. Participants played the Trust Game with the strategy method; results need replication with a clinical sample. Individuals high in social anxiety showed reduced reciprocal, but intact trustful giving, pointing to a constraint in responsiveness. The research may contribute to the development of new treatment and prevention programs to reduce the interpersonal impairments in socially anxious individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Grooming reciprocity in male Tibetan macaques.

Science.gov (United States)

Xia, Dong-Po; Li, Jin-Hua; Garber, Paul A; Matheson, Megan D; Sun, Bing-Hua; Zhu, Yong

2013-10-01

In several primate species, adult males are reported to compete for access to reproductive partners as well as forming affiliative and cohesive social bonds based on the exchange of goods or services. We hypothesized that among a broad set of fitness-maximizing strategies, grooming can be used by individual adult males to enhance social relationships through reciprocity and/or through the interchange of grooming for a different but equivalent good or service. We used focal animal sampling and continuously recorded dyadic grooming and agonistic interactions to test a series of predictions regarding male social interactions in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China. During the non-mating season or between males of similar rank throughout the year, grooming effort given was matched by grooming effort received. However, lower ranking males groomed higher ranking males at a greater rate and/or for a longer duration during both the mating and non-mating periods. We found that higher ranking males directed less aggression towards males with whom they formed a frequent grooming partnership, indicating that grooming received was interchanged for increased social tolerance. These data suggest that individual male Tibetan macaques employ alternative social strategies associated with grooming reciprocity or interchange depending on dominance rank and rates of aggression, and highlight the importance of both biological markets and grooming reciprocity as behavioral mechanisms used by resident adult males to form and maintain affiliative social bonds. © 2013 Wiley Periodicals, Inc.

Reciprocity in Vector Acoustics

Science.gov (United States)

2017-03-01

Green’s Theorem to the left hand side of Equation (3.2) converts it to a surface integral that vanishes for the impedance boundary conditions one...There are situations where this assumption does not hold, such as at boundaries between layers or in an inhomogeneous layer , because the density gradient...instead of requiring one model run for each source location. Application of the vector-scalar reciprocity principle is demonstrated with analytic

Identification of groundwater flow parameters using reciprocal data from hydraulic interference tests

Science.gov (United States)

Marinoni, Marianna; Delay, Frederick; Ackerer, Philippe; Riva, Monica; Guadagnini, Alberto

2016-08-01

We investigate the effect of considering reciprocal drawdown curves for the characterization of hydraulic properties of aquifer systems through inverse modeling based on interference well testing. Reciprocity implies that drawdown observed in a well B when pumping takes place from well A should strictly coincide with the drawdown observed in A when pumping in B with the same flow rate as in A. In this context, a critical point related to applications of hydraulic tomography is the assessment of the number of available independent drawdown data and their impact on the solution of the inverse problem. The issue arises when inverse modeling relies upon mathematical formulations of the classical single-continuum approach to flow in porous media grounded on Darcy's law. In these cases, introducing reciprocal drawdown curves in the database of an inverse problem is equivalent to duplicate some information, to a certain extent. We present a theoretical analysis of the way a Least-Square objective function and a Levenberg-Marquardt minimization algorithm are affected by the introduction of reciprocal information in the inverse problem. We also investigate the way these reciprocal data, eventually corrupted by measurement errors, influence model parameter identification in terms of: (a) the convergence of the inverse model, (b) the optimal values of parameter estimates, and (c) the associated estimation uncertainty. Our theoretical findings are exemplified through a suite of computational examples focused on block-heterogeneous systems with increased complexity level. We find that the introduction of noisy reciprocal information in the objective function of the inverse problem has a very limited influence on the optimal parameter estimates. Convergence of the inverse problem improves when adding diverse (nonreciprocal) drawdown series, but does not improve when reciprocal information is added to condition the flow model. The uncertainty on optimal parameter estimates is

Continuous Improvement in State Funded Preschool Programs

Science.gov (United States)

Jackson, Sarah L.

2012-01-01

State funded preschool programs were constantly faced with the need to change in order to address internal and external demands. As programs engaged in efforts towards change, minimal research was available on how to support continuous improvement efforts within the context unique to state funded preschool programs. Guidance available had…

Preschool Teachers' Use of ICTs: Towards a Typology of Practice

Science.gov (United States)

Masoumi, Davoud

2015-01-01

This study aimed to identify the ways in which information and communication technologies (ICT) are integrated in three preschools in south-western Sweden. The case study involved observations of and interviews with preschool teachers. The findings support claims that ICT can enhance preschool practices by providing a variety of complementary…

Network homophily and the evolution of the pay-it-forward reciprocity.

Directory of Open Access Journals (Sweden)

Yen-Sheng Chiang

Full Text Available The pay-it-forward reciprocity is a type of cooperative behavior that people who have benefited from others return favors to third parties other than the benefactors, thus pushing forward a cascade of kindness. The phenomenon of the pay-it-forward reciprocity is ubiquitous, yet how it evolves to be part of human sociality has not been fully understood. We develop an evolutionary dynamics model to investigate how network homophily influences the evolution of the pay-it-forward reciprocity. Manipulating the extent to which actors carrying the same behavioral trait are linked in networks, the computer simulation model shows that strong network homophily helps consolidate the adaptive advantage of cooperation, yet introducing some heterophily to the formation of network helps advance cooperation's scale further. Our model enriches the literature of inclusive fitness theory by demonstrating the conditions under which cooperation or reciprocity can be selected for in evolution when social interaction is not confined exclusively to relatives.

Network homophily and the evolution of the pay-it-forward reciprocity.

Science.gov (United States)

Chiang, Yen-Sheng; Takahashi, Nobuyuki

2011-01-01

The pay-it-forward reciprocity is a type of cooperative behavior that people who have benefited from others return favors to third parties other than the benefactors, thus pushing forward a cascade of kindness. The phenomenon of the pay-it-forward reciprocity is ubiquitous, yet how it evolves to be part of human sociality has not been fully understood. We develop an evolutionary dynamics model to investigate how network homophily influences the evolution of the pay-it-forward reciprocity. Manipulating the extent to which actors carrying the same behavioral trait are linked in networks, the computer simulation model shows that strong network homophily helps consolidate the adaptive advantage of cooperation, yet introducing some heterophily to the formation of network helps advance cooperation's scale further. Our model enriches the literature of inclusive fitness theory by demonstrating the conditions under which cooperation or reciprocity can be selected for in evolution when social interaction is not confined exclusively to relatives.

The status of preschool teachers in two municipalities following the economic collapse

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Laufey Axelsdóttir

2014-06-01

Full Text Available This feminist study examines the working conditions of preschool teachers, a female dominated occupation, in two municipalities in Iceland and asks, in light of government policy, if and then how the municipalities facilitate preschool teachers professionalism following the 2008 bank collapse. Weber´s (2001 theoretical framework is applied to explore the professional status of the preschools and the impact of local government on preschool teachers’ position. Qualitative methods were used and data was gathered in 2011 and 2012. Thirteen interviews were conducted with women and men in two preschools and the schools administrative environment. Preschool teachers employed in management and non-management positions as well as assistants were interviewed. The study’s results show that financial cutbacks in local government affect preschool teachers and assistants and thus the position of women in the labour market by preserving their subordination. Furthermore, preschool children seem to be affected by the cutbacks which possibly have negative consequences on their well-being. Reforms and developments of the preschool teachers education seem to be met with considerable opposition from local government and more emphasis is placed on operational costs rather than strengthening the preschool teachers in their role as professionals. The results thus point to a gap between government policy and the municipalities’ local version of that same policy.

Preschool Teachers' Level of Attitudes toward Early Mathematics Education

OpenAIRE

Çelik, Meryem

2017-01-01

Purpose of this study isexamining the preschool teachers' level of attitudes toward early mathseducation and correlation between these levels and various variables.“Preschool Teachers' Attitudes towards Early Childhood Math AssessmentInstrument" is applied to 60 teachers who were pre-school teachers in 2013and formed the sample of this study. As a result of these analysis, it has beenprecipitated that teachers' level of attitudes toward early maths education isgood. Meanin...

Neck Circumference to Assess Obesity in Preschool Children.

Science.gov (United States)

Kondolot, Meda; Horoz, Duygu; Poyrazoğlu, Serpil; Borlu, Arda; Öztürk, Ahmet; Kurtoğlu, Selim; Mazıcıoğlu, Mümtaz M

2017-03-01

Limited information is available about the use of neck circumference (NC) to assess obesity in preschool children. This study aims to provide NC percentiles and determine the cut-off levels of NC as a measure to assess obesity in preschool children. The data were obtained from the Anthropometry of Turkish Children aged 0-6 years (ATCA-06) study database. A total of 21 family health centers were chosen and children aged 2-6 years old from all socioeconomic levels were randomly selected from the lists of district midwives; 1766 children (874 male and 892 female; 88.3% of sample size) were included in the study. The smoothed centile curves of NC were constructed by the LMS method. Receiver operating characteristic (ROC) analysis was performed to calculate cut-off points for NC using body mass index ≥95 th percentile. Mean NC was greater in males than females. Cut-off values for obesity were found to be statistically significant in both genders other than 3 years old boys. The NC percentiles of Turkish preschool children were slightly greater than those of other European preschool children in both genders. This difference disappeared around the adiposity rebound period. The 97th percentile values for Turkish preschool children continue to be greater in both genders. NC may be useful to define obesity in preschool children. Since ethnic and various other factors may have a role in incidence of obesity, local reference data are important in assessment of obesity.

Rejection of unfair offers in the ultimatum game is no evidence of strong reciprocity

Science.gov (United States)

Yamagishi, Toshio; Horita, Yutaka; Mifune, Nobuhiro; Hashimoto, Hirofumi; Li, Yang; Shinada, Mizuho; Miura, Arisa; Inukai, Keigo; Takagishi, Haruto; Simunovic, Dora

2012-01-01

The strong reciprocity model of the evolution of human cooperation has gained some acceptance, partly on the basis of support from experimental findings. The observation that unfair offers in the ultimatum game are frequently rejected constitutes an important piece of the experimental evidence for strong reciprocity. In the present study, we have challenged the idea that the rejection response in the ultimatum game provides evidence of the assumption held by strong reciprocity theorists that negative reciprocity observed in the ultimatum game is inseparably related to positive reciprocity as the two sides of a preference for fairness. The prediction of an inseparable relationship between positive and negative reciprocity was rejected on the basis of the results of a series of experiments that we conducted using the ultimatum game, the dictator game, the trust game, and the prisoner’s dilemma game. We did not find any correlation between the participants’ tendencies to reject unfair offers in the ultimatum game and their tendencies to exhibit various prosocial behaviors in the other games, including their inclinations to positively reciprocate in the trust game. The participants’ responses to postexperimental questions add support to the view that the rejection of unfair offers in the ultimatum game is a tacit strategy for avoiding the imposition of an inferior status. PMID:23188801

Rejection of unfair offers in the ultimatum game is no evidence of strong reciprocity.

Science.gov (United States)

Yamagishi, Toshio; Horita, Yutaka; Mifune, Nobuhiro; Hashimoto, Hirofumi; Li, Yang; Shinada, Mizuho; Miura, Arisa; Inukai, Keigo; Takagishi, Haruto; Simunovic, Dora

2012-12-11

The strong reciprocity model of the evolution of human cooperation has gained some acceptance, partly on the basis of support from experimental findings. The observation that unfair offers in the ultimatum game are frequently rejected constitutes an important piece of the experimental evidence for strong reciprocity. In the present study, we have challenged the idea that the rejection response in the ultimatum game provides evidence of the assumption held by strong reciprocity theorists that negative reciprocity observed in the ultimatum game is inseparably related to positive reciprocity as the two sides of a preference for fairness. The prediction of an inseparable relationship between positive and negative reciprocity was rejected on the basis of the results of a series of experiments that we conducted using the ultimatum game, the dictator game, the trust game, and the prisoner's dilemma game. We did not find any correlation between the participants' tendencies to reject unfair offers in the ultimatum game and their tendencies to exhibit various prosocial behaviors in the other games, including their inclinations to positively reciprocate in the trust game. The participants' responses to postexperimental questions add support to the view that the rejection of unfair offers in the ultimatum game is a tacit strategy for avoiding the imposition of an inferior status.

Science and mathematics teaching through local games in preschools of Botswana

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Kabita Bose

2016-11-01

Full Text Available This article presents a study regarding preschool teachers’ skills and competencies in teaching science and mathematics. The aim of the project was twofold; one to find out the preschool teachers’ knowledge about mathematics and science concepts and then to develop support material to empower them with skills and competencies to teach these concepts in preschools. A qualitative approach was adopted, and a case study method was used. Data were collected through two workshops and focus group discussions with preschool teachers. The study revealed that the preschool teachers had content knowledge, but lacked pedagogical knowledge that is crucial in teaching of preschool children, and they provided science and mathematics experiences in preschools scarcely. A resource book of 33 local games and rhymes thus was developed as a support material to empower the teachers with skills and competencies to use play to teach science and mathematics in preschools. The resource book developed consists of 33 local games/rhymes and is packaged with the games’ illustrations, steps and rules followed in the games, science and mathematics concepts and competencies that could be taught to children, along with probing questions that would help in teaching of science and mathematics concepts to children.

32 CFR 2001.44 - Reciprocity of use and inspection of facilities.

Science.gov (United States)

2010-07-01

... 32 National Defense 6 2010-07-01 2010-07-01 false Reciprocity of use and inspection of facilities. 2001.44 Section 2001.44 National Defense Other Regulations Relating to National Defense INFORMATION... INFORMATION Safeguarding § 2001.44 Reciprocity of use and inspection of facilities. (a) Once a facility is...

Reciprocal relations of transport coefficients in simple materials

International Nuclear Information System (INIS)

Lam, L.

1977-01-01

The cross effects of viscosity and heat conduction in anisotropic simple materials (solids or liquids) are given in the linear regime, using our dissipation function theory introduced recently. Depending on whether the temperature gradient or the heat flux is used in the dissipation function, we show that two different but unambiguous reciprocal relations between the transport coefficients follow. These are compared and contrasted with the confusing predictions from the Onsager theory, and to the results of rational thermodynamics. The uncertain experimental situation in regard to these reciprocal relations is discussed. Experimental tests are strongly urged. (orig.) [de

Quantum coherence: Reciprocity and distribution

Energy Technology Data Exchange (ETDEWEB)

Kumar, Asutosh, E-mail: asukumar@hri.res.in [Harish-Chandra Research Institute, Allahabad-211019 (India); Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094 (India)

2017-03-18

Quantum coherence is the outcome of the superposition principle. Recently, it has been theorized as a quantum resource, and is the premise of quantum correlations in multipartite systems. It is therefore interesting to study the coherence content and its distribution in a multipartite quantum system. In this work, we show analytically as well as numerically the reciprocity between coherence and mixedness of a quantum state. We find that this trade-off is a general feature in the sense that it is true for large spectra of measures of coherence and of mixedness. We also study the distribution of coherence in multipartite systems by looking at monogamy-type relation–which we refer to as additivity relation–between coherences of different parts of the system. We show that for the Dicke states, while the normalized measures of coherence violate the additivity relation, the unnormalized ones satisfy the same. - Highlights: • Quantum coherence. • Reciprocity between quantum coherence and mixedness. • Distribution of quantum coherence in multipartite quantum systems. • Additivity relation for distribution of quantum coherence in Dicke and “X” states.

An Evaluation of Preschool Education in the Awutu Efutu Senya ...

African Journals Online (AJOL)

The study examined the state of preschool education in the Winneba district with the intent of identifying strengths and weaknesses of the sub system. A comparison of rural and urban preschools in the district was also explored. A sample of 30 preschools made up of 16 public and 14 private ones were selected through ...

Peers as clinicians: Examining the impact of Stay Play Talk on social communication in young preschoolers with autism.

Science.gov (United States)

Barber, Angela B; Saffo, Rachel W; Gilpin, Ansley T; Craft, Lydia D; Goldstein, Howard

2016-01-01

Peer Mediated Interventions (PMIs) can be incorporated into integrated early childhood and preschool settings to address socialization impairments observed in children with ASD (Katz & Girolametto, 2013). However, research examining specific PMI strategies with young preschoolers remains limited. The current study examines the efficacy of the Stay, Play, Talk PMI (English, Shafer, Goldstein, & Kaczmerek, 1997) on the social communication skills of young preschool children diagnosed with an Autism Spectrum Disorder (ASD). Each of 3 typically developing children (ages 3-5 years) was paired with a child with an ASD (ages 3-4 years). Typically developing peers were taught to Stay with their friend, Play with their friend, and Talk to their friend. The child dyads played together during two, 20-min weekly sessions for 6-8 weeks. A multiple baseline design across participants was implemented to measure the impact of the Stay Play Talk strategies on social initiations and responses characterized by non-coordinated gestures, gestures, and words. Simulation Modeling Analysis was also conducted to confirm visual analysis. All 3 typical peer buddies and all 3 target children with ASD demonstrated increases in the frequency of their responses, reaching levels that greatly exceeded baseline levels. Further, social reciprocations increased among each dyad above baseline. Social initiations remained variable across dyads. Gains were not maintained two months post intervention. Results of this study corroborated previous findings that support the usefulness of PMIs to improve social communication of young children with ASD (Chan et al., 2009) and suggest an economical, naturally occurring approach to improve social communication during early childhood. Readers will gain knowledge regarding the social communication profile of children with ASD and how this profile can negatively impact language development and peer relationships. In addition, readers will be able to identify the

METHODIC OF DEVELOPMENT OF MOTOR GIFTEDNESS OF PRESCHOOL CHILDREN

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Светлана Юрьевна Федорова

2013-05-01

Full Text Available Education and training of gifted children today appropriate to consider as an important strategic task of modern society. In this context, the purpose of research is the development motor giftedness, which is particularly relevant at the stage of pre-school education, which is caused by age-preschoolers. Preschoolers' motor giftedness is considered by the author as developing integrated quality, including psychomotor skills, inclinations, increased motivation for motor activity. In the process of study the following methods are used:  the study and analysis of the scientific and methodological literature on studies, questioning, interview, testing of physical fitness, statistical data processing.The result of research work is methodic of development of motor giftedness on physical education in preschool. The author's methodic consists of four steps:  diagnostic, prognostic, practice and activity, social and pedagogical. Each step determines the inclusion of preschool children in sports and developing environment that meets his or her abilities and needs through the creation of certain social and educational conditions.The area of using results of the author's methodic is preschool and the system of improvement professional skill of teachers. DOI: http://dx.doi.org/10.12731/2218-7405-2013-4-31

Assessing fears of preschool children with nighttime fears by a parent version of the fear survey schedule for preschool children.

Science.gov (United States)

Kushnir, Jonathan; Gothelf, Doron; Sadeh, Avi

2015-01-01

Although excessive fears are common in preschool children, validated assessment tools for this age are lacking. Our aim was to modify and provide preliminary evidence of the utility of a preschoolers' fear screening tool, a parent-reported Fear Survey Schedule for Preschool Children (FSS-PC). 109 Israeli preschool children (aged 4-6 years) with chronic night time fears (NF) and 30 healthy children (controls) participated. The FSS-PC analysis included: 1) internal reliability, 2) correlations between FSS-PC scores and Child Behavior Checklist (CBCL) measures, 3) differences between NF and a comparison sample of FSS-PC scores, and 4) FSS-PC sensitivity in detecting change in NF following an intervention for NF. There were low-to-medium positive correlations between the FSS-PC scores and several internalizing scales of the CBCL measures. FSS-PC scores in the NF group were significantly higher than the control children's score. FSS-PC scores had adequate internal reliability and were also sensitive for detecting significant changes in fear levels following behavioral interventions. Unique cultural and environmental circumstances and specific study group. This new version of the FSS-PC may provide clinicians with a novel and useful screening tool for early assessment of fear- and anxiety-related phenomena of preschool children.

Reciprocal inhibition between motor neurons of the tibialis anterior and triceps surae in humans.

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Yavuz, Utku Ş; Negro, Francesco; Diedrichs, Robin; Farina, Dario

2018-05-01

Motor neurons innervating antagonist muscles receive reciprocal inhibitory afferent inputs to facilitate the joint movement in the two directions. The present study investigates the mutual transmission of reciprocal inhibitory afferent inputs between the tibialis anterior (TA) and triceps surae (soleus and medial gastrocnemius) motor units. We assessed this mutual mechanism in large populations of motor units for building a statistical distribution of the inhibition amplitudes during standardized input to the motor neuron pools to minimize the effect of modulatory pathways. Single motor unit activities were identified using high-density surface electromyography (HDsEMG) recorded from the TA, soleus (Sol), and medial gastrocnemius (GM) muscles during isometric dorsi- and plantarflexion. Reciprocal inhibition on the antagonist muscle was elicited by electrical stimulation of the tibial (TN) or common peroneal nerves (CPN). The probability density distributions of reflex strength for each muscle were estimated to examine the strength of mutual transmission of reciprocal inhibitory input. The results showed that the strength of reciprocal inhibition in the TA motor units was fourfold greater than for the GM and the Sol motor units. This suggests an asymmetric transmission of reciprocal inhibition between ankle extensor and flexor muscles. This asymmetry cannot be explained by differences in motor unit type composition between the investigated muscles since we sampled low-threshold motor units in all cases. Therefore, the differences observed for the strength of inhibition are presumably due to a differential reciprocal spindle afferent input and the relative contribution of nonreciprocal inhibitory pathways. NEW & NOTEWORTHY We investigated the mutual transmission of reciprocal inhibition in large samples of motor units using a standardized input (electrical stimulation) to the motor neurons. The results demonstrated that the disynaptic reciprocal inhibition exerted

The High/Scope Perry Preschool Study: A Case Study in Random Assignment.

Science.gov (United States)

Schweinhart, Lawrence J.

2000-01-01

Studied the long-term benefits of preschool programs for young children living in poverty in the High/Scope Perry Preschool Study, which examined the lives of 123 African Americans randomly divided into a preschool treatment group and a no-preschool comparison group. Cost-benefit analyses of data on these students to age 27 show beneficial effects…

Self-Efficacy and Performance in Mathematics: Reciprocal Determinism in 33 Nations

Science.gov (United States)

Williams, Trevor; Williams, Kitty

2010-01-01

Reciprocal determinism is a central premise of Bandura's (1986) social cognitive theory. Studies of the relationship between self-beliefs and performance tend to draw on this or related theories and usually endorse the notion of reciprocal determinism at a substantive-theoretical level. However, attempts to model this postulated mutual influence…

Using Excel's Solver Function to Facilitate Reciprocal Service Department Cost Allocations

Science.gov (United States)

Leese, Wallace R.

2013-01-01

The reciprocal method of service department cost allocation requires linear equations to be solved simultaneously. These computations are often so complex as to cause the abandonment of the reciprocal method in favor of the less sophisticated and theoretically incorrect direct or step-down methods. This article illustrates how Excel's Solver…

Reciprocity in Online Markets: Empirical Studies of Auction and Barter Markets

Science.gov (United States)

Ye, Shun

2013-01-01

My dissertation seeks to understand how reciprocity affects transaction outcomes and mechanism design in online markets. The first essay examines negative reciprocity illustrated as feedback-revoking behavior in the eBay auction market, focusing on its impact and implications for reputation system design. I utilize the biggest policy change of…

The Importance of Music in Preschool Education

Science.gov (United States)

Ehrlin, Anna; Gustavsson, Hans-Olof

2015-01-01

At a few universities in Sweden students can chose a preschool teacher education programme with a music profile. At one of these universities, a study was undertaken that aimed to explore student teachers' understanding of self as musician, their future professional role as a preschool teacher and how the education equips for that. Sixteen…

Characteristics of Preschoolers with Lower Perceived Competence

Science.gov (United States)

Coplan, Robert J.; Findlay, Leanne C.; Nelson, Larry J.

2004-01-01

The goal of the present study was to identify preschool children with "age-inappropriate" less positive self-perceptions, and to explore their parental and peer relationships as compared to their classmates with "age normal" self-perceptions. Participants were n = 127 preschool children ([M.sub.age] = 54.98 mos., SD = 8.21). Data were collected…

Corrupt reciprocity: An experiment

OpenAIRE

Graf Lambsdorff, Johann; Frank, Björn

2007-01-01

We let students play a corruption game, embedded into a variant of the ultimatum game. Those allotted the role of public servants chose between whistleblowing, opportunism and reciprocity by delivery (of a contract) and those acting as businesspeople chose how to frame the game and whether to blow the whistle. While opportunism and abstaining from whistleblowing is the Nash equilibrium, another likely outcome was that businesspeople allocate resources to punishing public servants for non-deli...

Age Specifics of Cognitive Activity Development in Preschool Age

OpenAIRE

Klopotova E.E.; Samkova I.A.

2017-01-01

This paper present results of the research on the specifics of cognitive activity development in preschool children. The hypothesis tested was that content and dynamic components of cognitive activity reveal themselves in a different way depending on the stage of preschool childhood. The authors reviewed the diagnostic tools suitable for studying cognitive activity in preschoolers and selected the techniques. The research proved that content and dynamic components of cognitive activity have t...

Augmented Reality: Daily Prayers for Preschooler Student

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Hendra Pradibta

2018-01-01

Full Text Available Education is one of the aspects that many synthesized with technology. Yet, this is contrary to the fact that where most of the learning materials are still based on text. This research aims to develop an alternative learning media by implementing Augmented Reality Technology for Preschooler students. Augmented Reality (AR is an application that can combine the virtual object as text, pictures and animation into the real world. Development of Augmented Reality application uses Web Aurasma Based Studio, with learning materials of daily prayer for preschool student. The development of the characters and the animations were using Adobe Illustrator and Adobe After Effects. The results of the study showed that technology Augmented Reality can be used as an alternative learning media especially in the learning process in Preschool Al Furqon. This is because the content Augmented Reality in the form of animation can gives more understanding and attention for preschool student to follow the learning process

Reciprocal selection causes a coevolutionary arms race between crossbills and lodgepole pine.

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Benkman, Craig W; Parchman, Thomas L; Favis, Amanda; Siepielski, Adam M

2003-08-01

Few studies have shown both reciprocal selection and reciprocal adaptations for a coevolving system in the wild. The goal of our study was to determine whether the patterns of selection on Rocky Mountain lodgepole pine (Pinus contorta spp. latifolia) and red crossbills (Loxia curvirostra complex) were concordant with earlier published evidence of reciprocal adaptations in lodgepole pine and crossbills on isolated mountain ranges in the absence of red squirrels (Tamiasciurus hudsonicus). We found that selection (directional) by crossbills on lodgepole pine where Tamiasciurus are absent was divergent from the selection (directional) exerted by Tamiasciurus on lodgepole pine. This resulted in divergent selection between areas with and without Tamiasciurus that was congruent with the geographic patterns of cone variation. In the South Hills, Idaho, where Tamiasciurus are absent and red crossbills are thought to be coevolving with lodgepole pine, crossbills experienced stabilizing selection on bill size, with cone structure as the agent of selection. These results show that crossbills and lodgepole pine exhibit reciprocal adaptations in response to reciprocal selection, and they provide insight into the traits mediating and responding to selection in a coevolutionary arms race.

Asymmetric information capacities of reciprocal pairs of quantum channels

Science.gov (United States)

Rosati, Matteo; Giovannetti, Vittorio

2018-05-01

Reciprocal pairs of quantum channels are defined as completely positive transformations which admit a rigid, distance-preserving, yet not completely positive transformation that allows one to reproduce the outcome of one from the corresponding outcome of the other. From a classical perspective these transmission lines should exhibit the same communication efficiency. This is no longer the case in the quantum setting: explicit asymmetric behaviors are reported studying the classical communication capacities of reciprocal pairs of depolarizing and Weyl-covariant channels.

Reciprocity relations in transmission electron microscopy: A rigorous derivation.

Science.gov (United States)

Krause, Florian F; Rosenauer, Andreas

2017-01-01

A concise derivation of the principle of reciprocity applied to realistic transmission electron microscopy setups is presented making use of the multislice formalism. The equivalence of images acquired in conventional and scanning mode is thereby rigorously shown. The conditions for the applicability of the found reciprocity relations is discussed. Furthermore the positions of apertures in relation to the corresponding lenses are considered, a subject which scarcely has been addressed in previous publications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Toward An Ethics of Reciprocity: Ethnobotanical Knowledge and Medicinal Plants as Cancer Therapies

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John Charles Ryan

2014-10-01

Full Text Available This article develops a reciprocity ethics of the environment through a discussion of ethnobotanical medicines used in the treatment of cancer. The moral virtue of reciprocity, defined as the returning of good when good is received or anticipated, is central to the posthumanist rethinking of human relationships to the plant world. As herbal medicines are used progressively more around the globe and as plant diversity decreases as a result of habitat loss and climate change, an ethics of reciprocity should be a concern for environmental philosophers and conservationists. Aldo Leopold’s land ethic and J. Baird Callicott’s distinction between deontological and prudential environmental ethics provide theoretical contexts for the development of a reciprocity ethics vis-à-vis ethnobotanical species. While this article does not necessarily specify modes or forms of reciprocity, it does outline some of the more prominent ethnobotanical species used in the treatment of cancer, including those from Native American, African, Chinese, and Indian traditions. In the form of a dialogue between the fields of ethnobotany, herbal medicine, and environmental philosophy, this article presents a position from which further articulations of reciprocity can be developed, particularly those involving the rights of indigenous cultures and plants.

Science and Mathematics Teaching Efficacy Beliefs of Pre-School Teachers

Science.gov (United States)

Aydogdu, Bülent; Peker, Murat

2016-01-01

The aim of this research was to examine science and mathematics teaching efficacy beliefs of pre-school teachers in terms of some variables. The sample of the study was comprised of 191 pre-school teachers working in a city in Aegean Region of Turkey. Since it attempted to define self-efficacy beliefs of pre-school teachers toward science and…

Cerebral Palsy Checklist: Babies & Preschoolers (Birth to age 5)

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... Staying Safe Videos for Educators Search English Español Cerebral Palsy Checklist: Babies & Preschoolers KidsHealth / For Parents / Cerebral Palsy Checklist: Babies & Preschoolers What's in this article? Step ...

A new measure of child vocal reciprocity in children with autism spectrum disorder.

Science.gov (United States)

Harbison, Amy L; Woynaroski, Tiffany G; Tapp, Jon; Wade, Joshua W; Warlaumont, Anne S; Yoder, Paul J

2018-03-06

Children's vocal development occurs in the context of reciprocal exchanges with a communication partner who models "speechlike" productions. We propose a new measure of child vocal reciprocity, which we define as the degree to which an adult vocal response increases the probability of an immediately following child vocal response. Vocal reciprocity is likely to be associated with the speechlikeness of vocal communication in young children with autism spectrum disorder (ASD). Two studies were conducted to test the utility of the new measure. The first used simulated vocal samples with randomly sequenced child and adult vocalizations to test the accuracy of the proposed index of child vocal reciprocity. The second was an empirical study of 21 children with ASD who were preverbal or in the early stages of language development. Daylong vocal samples collected in the natural environment were computer analyzed to derive the proposed index of child vocal reciprocity, which was highly stable when derived from two daylong vocal samples and was associated with speechlikeness of vocal communication. This association was significant even when controlling for chance probability of child vocalizations to adult vocal responses, probability of adult vocalizations, or probability of child vocalizations. A valid measure of children's vocal reciprocity might eventually improve our ability to predict which children are on track to develop useful speech and/or are most likely to respond to language intervention. A link to a free, publicly-available software program to derive the new measure of child vocal reciprocity is provided. Autism Res 2018. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. Children and adults often engage in back-and-forth vocal exchanges. The extent to which they do so is believed to support children's early speech and language development. Two studies tested a new measure of child vocal reciprocity using computer-generated and real

Constructing and deriving reciprocal trigonometric relations: a functional analytic approach.

Science.gov (United States)

Ninness, Chris; Dixon, Mark; Barnes-Holmes, Dermot; Rehfeldt, Ruth Anne; Rumph, Robin; McCuller, Glen; Holland, James; Smith, Ronald; Ninness, Sharon K; McGinty, Jennifer

2009-01-01

Participants were pretrained and tested on mutually entailed trigonometric relations and combinatorially entailed relations as they pertained to positive and negative forms of sine, cosine, secant, and cosecant. Experiment 1 focused on training and testing transformations of these mathematical functions in terms of amplitude and frequency followed by tests of novel relations. Experiment 2 addressed training in accordance with frames of coordination (same as) and frames of opposition (reciprocal of) followed by more tests of novel relations. All assessments of derived and novel formula-to-graph relations, including reciprocal functions with diversified amplitude and frequency transformations, indicated that all 4 participants demonstrated substantial improvement in their ability to identify increasingly complex trigonometric formula-to-graph relations pertaining to same as and reciprocal of to establish mathematically complex repertoires.

Intensity and resolution of a general scan in reciprocal space

International Nuclear Information System (INIS)

Lebech, B.; Nielsen, M.

1975-01-01

Elastic neutron scattering on single crystals is traditionally carried out either by rotating the sample and keeping the detector fixed, or by coupling the detector rotation to the sample rotation in the the ratio 2:1. In recent years, a number of papers have discussed the feasibility of other types of scans. General scans at oblique angles to reciprocal lattice vectors are commonly used in inelastic neutron scattering. Such scans are also useful in elastic neutron scattering and may easily be made by means of computer or tape controlled diffractometers. Formulas are derived for the intensity and width of Bragg reflections measured by scanning at oblique angles to reciprocal lattice vectors. The results of the calculations are compared to experimental results on simple structures. The limitations of general scans in reciprocal space are also discussed

Punishment Insensitivity and Impaired Reinforcement Learning in Preschoolers

Science.gov (United States)

Briggs-Gowan, Margaret J.; Nichols, Sara R.; Voss, Joel; Zobel, Elvira; Carter, Alice S.; McCarthy, Kimberly J.; Pine, Daniel S.; Blair, James; Wakschlag, Lauren S.

2014-01-01

Background: Youth and adults with psychopathic traits display disrupted reinforcement learning. Advances in measurement now enable examination of this association in preschoolers. The current study examines relations between reinforcement learning in preschoolers and parent ratings of reduced responsiveness to socialization, conceptualized as a…

Domains of reciprocity beyond monetary compensation: How do non-pecuniary factors affect effort and shirking?

Directory of Open Access Journals (Sweden)

Akinori Tomohara

2016-12-01

Full Text Available This empirical study examines how sources of reciprocity are related to work motivation by distinguishing positive and negative work attitudes in practical working environments. We move away from the unidimensional perspective of monetary compensation and investigate employees’ reciprocal behaviors, together with non-pecuniary aspects of work relations such as human relationships and company management. The results show that positive reciprocity, represented by effort, is fundamentally distinct from negative reciprocity, represented by shirking, when examining the multi-dimensional sources of reciprocity. Additionally, our analyses reveal that non-pecuniary factors in the working environment have a relatively large degree of association with work motivation, even when compared to monetary compensation. Our results complement those from controlled laboratory experiments.

ADHD in Preschool: Approaches and Teacher Training

Science.gov (United States)

Singh, Ajay; Squires, Jane

2014-01-01

Due to the prevalence of ADHD, there is a need for early intervention at the preschool level to improve children's chance of academic success in later years. Yet few preschool teachers are trained to meet the challenges children with ADHD present. This paper gives a rationale and curriculum for teacher training in ADHD, with an emphasis on Social…

Research of Fears of Preschool Age Children

Science.gov (United States)

Konkabayeva, Aiman E.; Dakhbay, Beybitkhan D.; Oleksyuk, Z?ryana Ya.; Tykezhanova, Gulmira M.; Alshynbekova, Gulnaziya K.; Starikova, Anna Ye.

2016-01-01

One of the symptoms of neurosis at preschool age children is fear. In our opinion, research in this area will help to solve a number of problems of children of preschool age, including difficulties of acceptance on themselves in the new social roles in relation from kindergarten transition to school adjustment problems and a number of other…

The State of Preschool 2012: State Preschool Yearbook. Executive Summary

Science.gov (United States)

Barnett, W. Steven; Carolan, Megan E.; Fitzgerald, Jen; Squires, James H.

2012-01-01

The 2012 "State Preschool Yearbook" profiles state-funded prekindergarten programs in the United States. The "Yearbook" compares each state program's standards against a checklist of 10 research-based quality standards benchmarks. Although the benchmarks against which the National Institute for Early Education Research (NIEER)…

Understanding Barriers and Solutions Affecting Preschool Attendance in Low-Income Families

Science.gov (United States)

Susman-Stillman, Amy; Englund, Michelle M.; Storm, Karen J.; Bailey, Ann E.

2018-01-01

Preschool attendance problems negatively impact children's school readiness skills and future school attendance. Parents are critical to preschoolers' attendance. This study explored parental barriers and solutions to preschool attendance in low-income families. School-district administrative data from a racially/ethnically diverse sample of…

Effect of processing conditions on quality of green beans subjected to reciprocating agitation thermal processing.

Science.gov (United States)

Singh, Anika; Singh, Anubhav Pratap; Ramaswamy, Hosahalli S

2015-12-01

The effect of reciprocating agitation thermal processing (RA-TP) on quality of canned beans was evaluated in a lab-scale reciprocating retort. Green beans were selected due to their soft texture and sensitive color. Green beans (2.5cm length×0.8cm diameter) were filled into 307×409 cans with carboxylmethylcellulose (0-2%) solutions and processed at different temperatures (110-130°C) and reciprocation frequency (1-3Hz) for predetermined heating times to achieve a process lethality (F o ) of 10min. Products processed at higher temperatures and higher reciprocation frequencies resulted in better retention of chlorophyll and antioxidant activity. However, high reciprocation frequency also resulted in texture losses, with higher breakage of beans, increased turbidity and higher leaching. There was total loss of product quality at the highest agitation speed, especially with low viscosity covering solutions. Results suggest that reciprocating agitation frequency needs to be adequately moderated to get the best quality. For getting best quality, particularly for canned liquid particulate foods with soft particulates and those susceptible to high impact agitation, a gentle reciprocating motion (~1Hz) would be a good compromise. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of preschool-teacher-efficacy, social skills and work satisfaction on mental health

OpenAIRE

前田, 直樹; 金丸, 靖代; 畑田, 惣一郎; マエダ, ナオキ; カネマル, ヤスヨ; ハタダ, ソウイチロウ; Naoki, MAEDA; Yasuyo, KANEMARU; Soichiro, HATADA

2009-01-01

The purpose of the present study was to investigate preschool teacher's mental health and to examine the influence of preschool-teacher-efficacy, social skills and work satisfaction on their mental health. One hundred preschool teachers (8 males, 92 females) were administered a questionnaire including preschool teacher-efficacy scale, Kiss-18, work satisfaction scale and BDI-II. With regard to the situation of mental health, preschool teachers scored slightly lower than the general level. Pas...

The Parent Version of the Preschool Social Skills Rating System: Psychometric Analysis and Adaptation with a German Preschool Sample

Science.gov (United States)

Hess, Markus; Scheithauer, Herbert; Kleiber, Dieter; Wille, Nora; Erhart, Michael; Ravens-Sieberer, Ulrike

2014-01-01

The Social Skills Rating System (SSRS) developed by Gresham and Elliott (1990) is a multirater, norm-referenced instrument measuring social skills and adaptive behavior in preschool children. The aims of the present study were (a) to test the factorial structure of the Parent Form of the SSRS for the first time with a German preschool sample (391…

Supervisory behavior, reciprocity and subordinate absenteeism

NARCIS (Netherlands)

Dierendonck, van D.; Blanc, Le P.M.; Breukelen, van W.

2002-01-01

The present study among 242 professionals working in a lung clinic and nursing home was designed to test a model that links supervisory behavior (i.e. leader member exchange (LMX) behavior and conflict management behavior) and reciprocity in the supervisor/subordinate relationship to objectively

Preschool Children's Conceptions of Moral and Social Rules.

Science.gov (United States)

Smetana, Judith G.

1981-01-01

Examined preschool children's conceptions of moral and conventional rules. Children judged the seriousness, rule contingency, rule relativism, and amount of deserved punishment for 10 depicted moral and conventional preschool transgressions. Constant across ages and sexes, children evaluated moral transgressions as more serious offenses and more…

Rapid characterization of a nanomaterial structure using X-ray reciprocal-lattice-space imaging

International Nuclear Information System (INIS)

Sakata, Osami; Yoshimoto, Mamoru; Miki, Kazushi

2006-01-01

The X-ray reciprocal-lattice-space imaging method is able to record the reciprocal-lattice-space of nanostructure by sample-and-detector fixed geometry. This method was developed by the surface structure analysis beam line BL13XU of SPring-8. Outline of the X-ray diffraction method and basic principles of the X-ray reciprocal-lattice-space imaging method, and application examples are stated. The method is able to find out the Bragg conditions of nanostructure of surface in the atmosphere. The reciprocal-lattice of the embedded trace atomic wires was observed. The trace atoms of Bi atomic wires embedded in silicone showed the diffraction signal and image by a short exposure time. This method is useful at rapid non-destructive measurement of nanostructure. (S.Y.)

Punishment diminishes the benefits of network reciprocity in social dilemma experiments.

Science.gov (United States)

Li, Xuelong; Jusup, Marko; Wang, Zhen; Li, Huijia; Shi, Lei; Podobnik, Boris; Stanley, H Eugene; Havlin, Shlomo; Boccaletti, Stefano

2018-01-02

Network reciprocity has been widely advertised in theoretical studies as one of the basic cooperation-promoting mechanisms, but experimental evidence favoring this type of reciprocity was published only recently. When organized in an unchanging network of social contacts, human subjects cooperate provided the following strict condition is satisfied: The benefit of cooperation must outweigh the total cost of cooperating with all neighbors. In an attempt to relax this condition, we perform social dilemma experiments wherein network reciprocity is aided with another theoretically hypothesized cooperation-promoting mechanism-costly punishment. The results reveal how networks promote and stabilize cooperation. This stabilizing effect is stronger in a smaller-size neighborhood, as expected from theory and experiments. Contrary to expectations, punishment diminishes the benefits of network reciprocity by lowering assortment, payoff per round, and award for cooperative behavior. This diminishing effect is stronger in a larger-size neighborhood. An immediate implication is that the psychological effects of enduring punishment override the rational response anticipated in quantitative models of cooperation in networks. Copyright © 2017 the Author(s). Published by PNAS.

Preschool education as a determinant of educational attainment: An analysis of Serbia

Directory of Open Access Journals (Sweden)

Vuksanović Nemanja

2017-01-01

Full Text Available The subject of this paper is preschool education as a determinant of students’ educational attainment in Serbia and factors that influence whether a Serbian child is included in preschool programmes. This paper aims 1 to assess how attendance of preschool programmes in Serbia affects a student’s educational attainment in terms of mathematical, reading, and scientific literacy; 2 to explore how preschool education differs for students who occupy different positions in the distribution of educational attainment; and 3 to examine the determinants of a child in Serbia receiving preschool education. The analysis is based on data from PISA2012 testing. In order to assess the significance and nature of the effect of preschool education on educational attainment in terms of mathematical, reading, and scientific literacy we use unconditional quantile regression. To analyse factors that affect whether a child is included in the preschool programme we apply probit regression. Unconditional quantile regression results suggest that the sign and intensity of the effect of preschool education for more than a year are positive and increasing. The results of the probit regression show that socio-economic family background and parental status in the labour market are the factors that determine whether the student will attend preschool education for more than a year. The results indicate that the educational system in Serbia reproduces poverty and social exclusion.

Gifted Education in Preschool: Perceived Barriers and Benefits of Program Development

Science.gov (United States)

Kettler, Todd; Oveross, Mattie E.; Bishop, James C.

2017-01-01

Substantial evidence supports the benefits of quality preschool education for children of all levels and backgrounds. However, early childhood gifted education services rarely exist in preschool centers. This study included 263 preschool centers representing geographic diversity in a southern state in the United States. Narrative data were…

Harbingers of Artin's Reciprocity Law. I. The Continuing Story of Auxiliary Primes

OpenAIRE

Lemmermeyer, Franz

2011-01-01

In this article we present the history of auxiliary primes used in proofs of reciprocity laws from the quadratic to Artin's reciprocity law. We also show that the gap in Legendre's proof can be closed with a simple application of Gauss's genus theory.

Promoting mental health in Swedish preschool-teacher views.

Science.gov (United States)

Isaksson, Pernilla; Marklund, Bertil; Haraldsson, Katarina

2017-02-01

The promotion of childhood mental health is an important investment for the future. Many young children spend a large amount of time in preschool, which have unique opportunities to promote mental health at an early stage. The aim of this study was to illuminate teachers’ views of what they do in ordinary work to promote mental health among preschool children. This qualitative study had a descriptive and exploratory design and qualitative content analysis was utilized. Six focus group interviews with preschool teachers, concerning families from different cultural, geographical and socioeconomic backgrounds, were conducted in a county in the southwest of Sweden. Both manifest and latent content appeared. Three categories, ‘structured world’, ‘pleasant climate’ and ‘affirming the child’ and 10 subcategories emerged. The latent content of these categories is described under the theme ‘creating an atmosphere where each child can flourish in harmony with their environment’. The results show teachers different working approaches with mental health in preschool and together with previous research these results can provide a basis of knowledge for preschool teachers and inspire them to develop and maintain their health-promoting work. In future studies it should be particularly interesting to investigate how the promotive way to work can be transferred to strengthen mental health throughout the school years.

Hydropower harvesting from a small scale reciprocating system

Energy Technology Data Exchange (ETDEWEB)

Malla, Ramesh B.; Shrestha, Binu; Bagtzoglou, Amvrossios; Drasdis, Jonathon [Department of Civil and Environmental Engineering, University of Connecticut, 261 Glenbrook Road, Storrs, CT 06269-2037 (United States); Johnson, Paul [eGen LLC, 1084 Shennecossett Road, Groton, CT 06340 (United States)

2011-05-15

Conventional hydropower systems that can take advantage of low head movement of water require substantial flow rates. However, these systems cannot harvest hydro energy from small sources of water with low head and low discharge, such as streams and creeks. The reciprocating hydropower system discussed in this paper can harvest power from such low flow discharge and low head sources. This paper presents a detailed proof-of-concept study of the hydropower model, including the underlining theoretical principles. Laboratory test results demonstrating the dependence of the lift force in the reciprocating small scale hydropower model as a function of flow velocity, size and rotational speed of the cylinder and comparison of the results with a previous study are also included. Two methods of power harvesting from the output displacement obtained from the hydropower system are discussed. The first employs electromagnetic induction principles and the other is based on a linear inertial generator using a conventional second order spring mass damper system. Finally, results from a finite element analysis of the hydropower system are presented and facilitate future design of the structural aspects of the housing for the reciprocating cylinder. (author)

[Protocols Related to Food Allergies and Intolerances in Preschools in Reykjavik, Iceland].

Science.gov (United States)

Thrastardottir, Adalheidur Ran; Thordardottir, Frida Run; Torfadottir, Johanna

2018-01-01

The aim of the study was to explore prevalence of food allergies and intolerances among children in preschools in Reykjavik, Iceland. Also, to investigate how well preschools maintain a safe environment for children with food allergies. In 2014, a questionnaire designed specifically for this study, was sent to 65 preschools. Forty-nine participated (75%) representing a total of 4225 children. Prevalence of food allergy and intolerance was determined based on medical certificates from physi-cians delivered to the preschools. Descriptive statistics were used to assess whether there were protocols related to food allergy, and if there was a difference between schools based on staff's education and number of children. The prevalence of documented food allergies/intolerances in children aged 2-6 years was 5%, 1% had severe allergy and 1% had multiple food allergies. Lactose intolerance was most frequent (2%), then milk allergy (2%) and egg allergy (1%). Only 41% preschools had a protocol that was activated if food with an allergen was accidentally given. Moreover, only 55% of preschools with children with severe -allergy reported all of their staff to have knowledge of symptoms related to anaphylaxis and only 64% were trained to respond to an anaphylactic shock. The education of preschool principals, kitchen employees and number of children in preschool were not related to having an active protocol at site. Prevalence of food allergy and intolerance was 5% in preschools in Reykjavik. Strategy for an active protocol related to food allergy was lacking in 59% of pre-schools.

The Reciprocal Principle of Selectand-Selector-Systems in Supramolecular Chromatography †.

Science.gov (United States)

Schurig, Volker

2016-11-15

In selective chromatography and electromigration methods, supramolecular recognition of selectands and selectors is due to the fast and reversible formation of association complexes governed by thermodynamics. Whereas the selectand molecules to be separated are always present in the mobile phase, the selector employed for the separation of the selectands is either part of the stationary phase or is added to the mobile phase. By the reciprocal principle, the roles of selector and selectand can be reversed. In this contribution in honor of Professor Stig Allenmark, the evolution of the reciprocal principle in chromatography is reviewed and its advantages and limitations are outlined. Various reciprocal scenarios, including library approaches, are discussed in efforts to optimize selectivity in separation science.

A reciprocal framework for spatial K-anonymity

KAUST Repository

Ghinita, Gabriel; Zhao, Keliang; Papadias, Dimitris; Kalnis, Panos

2010-01-01

Spatial K-anonymity (SKA) exploits the concept of K-anonymity in order to protect the identity of users from location-based attacks. The main idea of SKA is to replace the exact location of a user U with an anonymizing spatial region (ASR) that contains at least K-1 other users, so that an attacker can pinpoint U with probability at most 1/K. Simply generating an ASR that includes K users does not guarantee SKA. Previous work defined the reciprocity property as a sufficient condition for SKA. However, the only existing reciprocal method, Hilbert Cloak, relies on a specialized data structure. In contrast, we propose a general framework for implementing reciprocal algorithms using any existing spatial index on the user locations. We discuss ASR construction methods with different tradeoffs on effectiveness (i.e., ASR size) and efficiency (i.e., construction cost). Then, we present case studies of applying our framework on top of two popular spatial indices (namely, R*-trees and Quad-trees). Finally, we consider the case where the attacker knows the query patterns of each user. The experimental results verify that our methods outperform Hilbert Cloak. Moreover, since we employ general-purpose spatial indices, the proposed system is not limited to anonymization, but supports conventional spatial queries as well. © 2009 Elsevier B.V. All rights reserved.

A reciprocal framework for spatial K-anonymity

KAUST Repository

Ghinita, Gabriel

2010-05-01

Spatial K-anonymity (SKA) exploits the concept of K-anonymity in order to protect the identity of users from location-based attacks. The main idea of SKA is to replace the exact location of a user U with an anonymizing spatial region (ASR) that contains at least K-1 other users, so that an attacker can pinpoint U with probability at most 1/K. Simply generating an ASR that includes K users does not guarantee SKA. Previous work defined the reciprocity property as a sufficient condition for SKA. However, the only existing reciprocal method, Hilbert Cloak, relies on a specialized data structure. In contrast, we propose a general framework for implementing reciprocal algorithms using any existing spatial index on the user locations. We discuss ASR construction methods with different tradeoffs on effectiveness (i.e., ASR size) and efficiency (i.e., construction cost). Then, we present case studies of applying our framework on top of two popular spatial indices (namely, R*-trees and Quad-trees). Finally, we consider the case where the attacker knows the query patterns of each user. The experimental results verify that our methods outperform Hilbert Cloak. Moreover, since we employ general-purpose spatial indices, the proposed system is not limited to anonymization, but supports conventional spatial queries as well. © 2009 Elsevier B.V. All rights reserved.

Cruel intentions on television and in real life: can viewing indirect aggression increase viewers' subsequent indirect aggression?

Science.gov (United States)

Coyne, Sarah M; Archer, John; Eslea, Mike

2004-07-01

Numerous studies have shown that viewing violence in the media can influence an individual's subsequent aggression, but none have examined the effect of viewing indirect aggression. This study examines the immediate effect of viewing indirect and direct aggression on subsequent indirect aggression among 199 children ages 11 to 14 years. They were shown an indirect, direct, or no-aggression video and their subsequent indirect aggression was measured by negative evaluation of a confederate and responses to a vignette. Participants viewing indirect or direct aggression gave a more negative evaluation of and less money to a confederate than participants viewing no-aggression. Participants viewing indirect aggression gave less money to the confederate than those viewing direct aggression. Participants viewing indirect aggression gave more indirectly aggressive responses to an ambiguous situation and participants viewing direct aggression gave more directly aggressive responses. This study provides the first evidence that viewing indirect aggression in the media can have an immediate impact on subsequent aggression.

Violation of Gribov-Lipatov reciprocity due to preconfinement

International Nuclear Information System (INIS)

Kawabe, Tetsuji

1981-01-01

On the basis of the preconfinement picture we study the hadronization of quark jets. Since this picture prepares in the final stage of QCD evolution the color singlet cluster for the adjacent q anti q pair distribution, the color of partons can be compensated in the hard region. We show that the resulting fragmentation function satisfies no longer the Gribov-Lipatov reciprocity derived in the case of the two-parton distribution. It is pointed out that the violation of the reciprocity is expected as the evidence of the realization of the preconfinement picture and the pattern of the violation is not inconsistent with data. (author)

Play or hard work: unpacking well-being at preschool.

Science.gov (United States)

Kennedy-Behr, A; Rodger, S; Mickan, S

2015-03-01

Well-being or quality of life is thought to give a more accurate picture of the impact a condition has on day-to-day functioning than traditional outcome measures. This study sought to examine the relationship between engagement in play and well-being for preschool children with and without developmental coordination disorder (DCD). A quasi-experimental design was used with two independent groups of preschool children aged 4-6 years with (n=32) and without (n=31) probable DCD. Play skills were assessed using the Play Observation Scale based on 30min of videotape of free-play at preschool. Well-being was assessed using a parent-proxy version of the Revised Children Quality of Life Questionnaire (KINDL(R)). Spearman rho correlations were performed to examine the relationship between play and well-being. Well-being at preschool was significantly lower for the children in the DCD group however overall well-being was not significantly different. Engagement in type of social play (solitary, parallel or group) was found to predict well-being for the typically developing children. For the children with DCD, engagement in group play was not associated with well-being. An explanation for this difference may be that children with DCD may not experience free-play at preschool as "play" but rather as hard work. Further research is needed to determine why children with DCD experience lower well-being at preschool than their peers and to investigate children's perceptions of free-play. This may enable teachers and therapists to better support children with DCD in the preschool environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nutrition Knowledge Assessment of Preschool Children

OpenAIRE

Plum, Jane Meacham Jr.

1997-01-01