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The majority of empirical research on responses to negative feedback has focused on affective responses to negative feedback, which have largely been adverse. The purpose of this study was to examine how negative feedback enhances motivation. A key feature of this study is the conceptualization of motivation using Edward Deci and Richard Ryan’s self-determination theory. Self-determination theory proposes a continuum of motivation, based on one’s regulation, or contingency for performance. Goal orientation and social dominance orientation are proposed as two moderators of the negative feedback-regulation relationship. Two studies were conducted to examine the relationship between negative feedback and regulation. Study 1 used a survey-based instrument with a work sample after a performance appraisal was conducted (N = 221), and Study 2 took place in a psychology statistics undergraduate course (N = 156). Negative feedback yielded a decrease in obligated motivation in Study 1. Mastery prove goal orientation and performance prove goal orientation were consistent significant moderators of the negative feedback-regulation relationship, such that individuals with high levels of Mastery prove goal orientation increased their autonomous regulation at higher levels of negative feedback, while individuals with high levels of performance prove goal orientation decreased their autonomous regulation at higher levels of negative feedback. Implications for feedback delivery are discussed. This study contributes to the literature by being the first to examine the effects of negative feedback on all forms of regulation, and is the first to use goal orientation and social dominance orientation as moderators of the negative feedback – regulation relationship. Further, this study demonstrated the positive motivational effects of giving positive feedback as well as setting mastery prove based goals.

A number of clinicians have reported that narcissists show grandiosity in self-concept, and rage after receiving disconfirming feedback. This is the first empirical study to test these claims. Subjects with differing levels of narcissism and self-esteem were compared on distortion in self-perception and emotional reaction to negative feedback. Ninety-six college students predicted their levels of intelligence, attractiveness, and interpersonal understanding (empathy) as compared to their peers. Objective measures of these characteristics were obtained, and subjects' predictions, with their actual scores held constant, provided measures of reality distortion in selfperception. Subjects were given feedback comparing their predictions to objective measures at the end of the experiment, and reaction to feedback was assessed by comparing subjects' pre- and post-feedback scores on the Multiple Affect Adjective Checklist-Revised (Zuckerman & Lubin, 1985). Narcissists were expected to react to negative feedback with greater hostility than nonnarcissists. Narcissists evidenced significant distortion in perceptions of their own intelligence, attractiveness, and interpersonal understanding. This finding provided empirical evidence supporting the clinical phenomenon of grandiosity. Narcissists did not react with greater hostility after negative feedback, but as compared to nonnarcissists, they did react with less depression following negative feedback. This supported Kernberg's (1980) assertion that narcissists do not react to loss with depression. In contrast to the inflated self-image associated with narcissism, self-esteem was associated with a comparatively accurate view of self.

Pannexins represent a recently discovered second family of gap junction proteins in vertebrates. However, instead of forming intercellular gap junction channels like connexins, pannexins operate as unpaired pannexons, allowing the flux of molecules from the cytoplasm to the extracellular space and vice versa. Pannexins appear to play a vital role in the local control loop of blood perfusion and oxygen delivery. The properties of Panx1 channels indicate that this protein is the most probable candidate for an ATP release channel and is involved in the propagation of intercellular calcium waves. It is also proposed to mediate the large pore formation of the P2X7 receptor death complex. Prolonged activation of this receptor can lead to cell death. There must be some mechanisms to stop this ATP-induced ATP release and opening of the lethal pore. Here we describe a negative feedback loop controlling pannexin 1 channel activity. ATP, permeant to pannexin 1 channels, was found to inhibit its permeation pathway when applied extracellularly. ATP analogues, including BzATP, suramine, and BBG were even more effective inhibitors of pannexin 1 currents than ATP. These compounds also attenuated the uptake of dyes by erythrocytes, which express pannexin 1. The rank order of the compounds in attenuation of pannexin 1 currents was similar to their binding affinities to the P2X7 receptor, except that receptor agonists and antagonists both were inhibitory to the channel. The ATP inhibitory effect is largely decreased when R75 on the first extracellular loop of Pannexin1 is mutated to alanine, strongly indicating that the ATP regulates this channel through binding. To further investigate the structural property of the ATP binding, we did alanine scanning mutagenesis of the extracellular loops and found that mutations on W74, S237, S240, I247 and L266 on the extracellular loops severely impair the BzATP inhibitory effect indicating that they might be direct binding partners for the ligands. Mutations on R75, S82, S93, L94, D241, S249, P259 and I267 have largely decreased BzATP sensitivity. Mutations on other residues didn't change the BzATP sensitivity compared to the wild type except for some nonfunctional mutants. All these data demonstrate that some amino acid residues on the extracellular loop of Pannexin 1 mediate ATP sensitivity. However, how these residues form the ATP-binding pocket remains to be elucidated.

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<p> </p><p>Millions of dollars change hands daily through online auction markets. Online trading communities like eBay and Amazon.com are emerging as increasingly important factors of the economy. Various Reputation systems are important components in such electronic markets. Existing evidence suggests that there are a number of problems with such systems. This paper presents an empirical exploration of reputation systems. Two studies of Tradera’s discussion forums are reported. The result of the first, pilot study suggests that both sellers and buyers are worried about getting a retaliatory negative feedback if they leave a negative feedback for an unsatisfactory transaction from their trading parties. Retaliation from the non-paying bidders seems to be the most severe threat and trouble for sellers. A set of negative feedbacks were then gathered from Tradera and data were manually analyzed in order to verify the results from the preliminary study. The results from the second study confirmed the result of the pilot study. A general evaluation of Tradera’s current reputation system is made based on the results of the second study. This paper aims to make a contribution to the literature on online reputation system by developing a typology of seller complaints about Tradera buyers and providing a tentative definition of retaliatory negative feedback based on the findings of both studies. Proposed solutions to the problems of non-payment and feedback retaliation are also presented.</p><p> </p>

The main contents of this thesis are improving a UWB LNA, and analyze the input-matching, the noise, and the gain. First we increase the width of the input transistor, and remove source-degeneration inductor. Those ways can increase the gain and reduce the noise of the circuit. In the input matching, we use a shunt capacitor, a series inductor, and the impedance of the transistor itself to achieve high frequency matching. The lower frequency matching is achieved by negative feedback resistor. The UWB LNA dissipates 10.14 mW power and achieves input return loss (S11) below -11.5 dB, output return loss (S22) below -11.9 dB, forward gain (S21) of 14.4¡Ó0.4 dB, reverse isolation (S12) below -26.7 dB, and noise figure (NF) of 2.6~3.5 dB over the 3.1~10.6 GHz band of interest. 1-dB compression point (P1dB) of -16.8 dBm and input third-order inter-modulation point (IIP3) of -8.1 dBm are achieved at 6.85 GHz.

This study investigated the effects of recasts, a frequently provided type of oral feedback in language teaching, on the production of English question forms in second language (L2) learning. Despite the large number of studies which have examined the effects of recasts, mixed views exist as to their usefulness as a corrective feedback technique. The present study has continued the investigation into whether their frequent use is justified and also if learners actually perceive recasts as being corrective in nature. The focus of this study is to explore developmental effects, both immediately following and delayed, of recasts while considering these two key aspects. The primary aim is to explore delayed benefits of recasts while the secondary aim is to investigate whether or not these learners perceived the feedback as a correct version of their incorrect question form. The study involved 34 English as a second language (ESL) learners from various first language (L1) backgrounds who were enrolled in a general English programme, at an Auckland language school. The participants completed demographic questionnaires and took part in task-based interaction sessions, with the members of the experimental group receiving input containing intensive recasts. The proportion and types of questions produced in the immediate and two delayed post-tests were compared and analysed to consider whether exposure to recasts was beneficial. The main findings suggest that for more advanced question types, interaction with intensive recasts may be more effective than interaction alone, for delayed L2 development, despite only weak support in the literature. On the other hand, similar positive effects on immediate question production are not strongly evident. Therefore, the results in this study add support to the claim that recasts may be beneficial for delayed second language acquisition (SLA), when the linguistic target is questions, even when these recasts do not seem effective immediately following exposure. Furthermore, awareness of negative evidence was indicated, which may have contributed, in part, to the positive delayed findings. Finally, these results suggest that recasts can be an effective pedagogical tool in the communicative L2 classroom when providing linguistic feedback in a way that does not unduly disrupt the flow of the interactive task. Practical suggestions for future research were also identified.

This study investigated the effects of recasts, a frequently provided type of oral feedback in language teaching, on the production of English question forms in second language (L2) learning. Despite the large number of studies which have examined the effects of recasts, mixed views exist as to their usefulness as a corrective feedback technique. The present study has continued the investigation into whether their frequent use is justified and also if learners actually perceive recasts as being corrective in nature. The focus of this study is to explore developmental effects, both immediately following and delayed, of recasts while considering these two key aspects. The primary aim is to explore delayed benefits of recasts while the secondary aim is to investigate whether or not these learners perceived the feedback as a correct version of their incorrect question form. The study involved 34 English as a second language (ESL) learners from various first language (L1) backgrounds who were enrolled in a general English programme, at an Auckland language school. The participants completed demographic questionnaires and took part in task-based interaction sessions, with the members of the experimental group receiving input containing intensive recasts. The proportion and types of questions produced in the immediate and two delayed post-tests were compared and analysed to consider whether exposure to recasts was beneficial. The main findings suggest that for more advanced question types, interaction with intensive recasts may be more effective than interaction alone, for delayed L2 development, despite only weak support in the literature. On the other hand, similar positive effects on immediate question production are not strongly evident. Therefore, the results in this study add support to the claim that recasts may be beneficial for delayed second language acquisition (SLA), when the linguistic target is questions, even when these recasts do not seem effective immediately following exposure. Furthermore, awareness of negative evidence was indicated, which may have contributed, in part, to the positive delayed findings. Finally, these results suggest that recasts can be an effective pedagogical tool in the communicative L2 classroom when providing linguistic feedback in a way that does not unduly disrupt the flow of the interactive task. Practical suggestions for future research were also identified.

Efficient directed migration requires tight regulation of chemoattractant signal transduction pathways in both space and time, but the mechanisms involved in such regulation are not well understood. Here, we investigated the role of protein kinase A (PKA) in controlling signaling of the chemoattractant cAMP in Dictyostelium discoideum. We found that cells lacking PKA display severe chemotaxis defects, including impaired directional sensing. Although PKA is an important regulator of developmental gene expression, including the cAMP receptor cAR1, our studies using exogenously expressed cAR1 in cells lacking PKA, cells lacking adenylyl cyclase A (ACA) and cells treated with the PKA-selective pharmacological inhibitor H89, suggest that PKA controls chemoattractant signal transduction, in part, through the regulation of RasG, Rap1 and TORC2. As these pathways control the ACA-mediated production of intracellular cAMP, they lie upstream of PKA in this chemoattractant signaling network. Consequently, we propose that the PKA-mediated regulation of the upstream RasG, Rap1 and TORC2 signaling pathways is part of a negative feedback mechanism controlling chemoattractant signal transduction during Dictyostelium chemotaxis.