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1.
The literature on feedback to individuals has previously been reviewed with respect to its effect on the behavior of individuals in performance-oriented organizations. Although contemporary views of individual behavior in organizations stress that feedback is necessary for effective role performance, little attention is given to the psychological processes affected by it. This review focuses on the multidimensional nature of feedback as a stimulus and addresses the process by which feedback influences behavior. Emphasis is placed on those aspects of feedback that influence (a) the way it is perceived, (b) its acceptance by the recipient, and (c) the willingness of the recipient to respond to the feedback. (3 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
Light has dual effects on the pineal melatonin; one is the entrainment of the circadian rhythm and the other is suppression of the melatonin synthesis. It is not known whether the entraining and suppressing effects of light are mediated by the same pathway or not. To elucidate the mechanism of the dual effects of light, (1) the sensitivity of the retina, (2) effects of acetylcholine agonist and, (3) the arrhythmicity induced by longterm continuous light, were studied by measuring melatonin continuously from a single rat by means of in vivo microdialysis. Pineal melatonin was suppressed by light more strongly at the late dark phase than at midnight, and by green light (520nm) than by red light (660nm). Pineal melatonin measured by microdialysis was decreased rapidly by a short light exposure and the melatonin rhythm was shifted on the following days. Microinjection of cholinergic agonist, carbachol, into the suprachiasmatic nucleus neither suppressed nor entrained the pineal melatonin rhythm. Immediately after the blinding, rats showed the circadian rhythm in pineal melatonin which had been abolished under long-term continuous light. While, it took several days for the locomotor rhythm to reappear. It is concluded that, (1) suppression of the pineal melatonin by light depends on the circadian phase and on the wavelength of light, (2) the threshold for light suppression is lower than that for phase-shift, (3) the melatonin rhythm starts to phase-shift on the following day of light pulse. (4) Acetylcholine is unlikely to be involved in the photic transmission both to the circadian clock and to the pineal, (5) arrhythmicity induced by long-term continuous light seems to be due to masking for the melatonin rhythm, and to uncoupling from the clock for the locomotor rhythm.  相似文献   

3.
Presents an analysis and simulation model of the verbal protocols of 2 college students and 1 8-yr-old S learning to program recursive functions. The model is formalized as a production system capable of acquiring new production rules based on problem-solving experience. The model and protocols suggest that (a) problem solving by analogy to worked-out examples is frequent in initial attempts by novices to write recursive functions; (b) different representations of examples are used to guide problem solving by analogy; and (c) performance on later problems reflects the particular representations used in problem solving by analogy on earlier problems. The protocols and simulations also suggest that learning is facilitated by using abstract representations of the structure of recursion examples to guide initial coding attempts. (French abstract) (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Using the whole-cell voltage-clamp technique, we have investigated the effect of nitric oxide (NO) donor (sodium nitroprusside, SNP) on hyperpolarization-activated inward current, I(f), in isolated rabbit sinoatrial node (SAN) cells. I(f) in the basal state increased when NO was applied but decreased when I(f) was pre-stimulated by isoproterenol (ISO) or by adding cAMP to the pipette solution. Both the stimulatory and the inhibitory effects of NO were abolished by guanylyl cyclase inhibitor, methylene blue (MB), suggesting that the effect of NO is mediated by cGMP. The inhibitory effect of NO was abolished when I(f) was pre-stimulated by 3-isobutyl-1-methylxanthine (IBMX), which is a phosphodiesterase (PDE) inhibitor, or by adding 8Br-cAMP (which is resistant to PDE) to the pipette solution. An analogue of cGMP, 8Br-cGMP, which is a potent stimulator of cGMP-dependent protein kinase (PKG) but has little effect on PDE, did not inhibit I(f) when I(f) was pre-stimulated by ISO. In its basal state, I(f) was still increased by 8Br-cGMP, and this effect was not prevented by the pretreatment with H-7, PKG inhibitor. The effect of acetylcholine (ACh) was not identical to that of NO: I(f) decreased when pre-stimulated not only by ISO, but also by IBMX. The above results suggest that via cGMP, NO exerts a dual effect on I(f): the inhibitory effect is mediated by cGMP-stimulated PDE, and the stimulatory effect may be attributable to direct binding of cGMP to I(f) channels.  相似文献   

5.
The mechanism of catecholamine (CA) release induced by transmural stimulation (TS) and the participation of acetylcholine (ACh) in this mechanism were studied using isotonic contraction of excised vas defernse of rats. Furthermore, the inhibitory effect of bretylium (Br) on sympathetic activity was observed. Results: 1) The effects of various kinds of drugs on isotonic contractions induced by TS, exogenous ACh and exogenous noradrenaline (NA) were observed with the results shown in Table 1. The following has been concluded: (1) TS-induced contraction is due to stimulation of the endings of hypogastric nerve (sympathetic nerve), resulting in CA release from adrenergic fiber (AF) and ACh release from cholinergic fiber (CF) in this nerve. (2) The participation of ACh is not indispensable in the CA release from AF induced by TS. (3) Endogenous ACh release from CF by TS brings about CA release under eserine application. (4) CA release by exogenous ACh is not inhibited by ganglion blockade, but is inhibited by atropine, indicating the muscarinic receptor to be in AF endings. 2) Br exerted preferentially the irreversible inhibition on CA release from AF rather than that on ACh release from CF, while it caused a mild reversible inhibition on CA release by exogenous ACh. 3) On the TS contraction that had been abolished irreversibly by Br, NA incubation showed a mild lasting recovery, while methamphetamine (MAP) or calcium (Ca) incubation showed a strong lasting recovery. Furthermore, in this recovery of TS contraction, the incubation with NA or MAP exerted only the recovery of CA release while the Ca incubation exerted the recovery of both CA release and ACH release. It would appear that Br blocks both AF and CF by inhibiting the transmitter-releasing action of Ca.  相似文献   

6.
Presents a connectionist model of visual search, Search via Recursive Rejection (SERR) by G. W. Humphreys and H. J. Muller (in press), in which search is determined by patterns of grouping between distractors and between simple form elements. The performance of SERR is examined after it is subject to various types of "lesion." Lesioning is produced either by increasing the internal noise on the activation functions governing the interactions between processing units or by eliminating processing units from different loci in SERR. Simulations demonstrate that (1) search processes can be disrupted by adding internal noise to search functions, (2) there can be selective effects on grouping processes, and (3) these selective effects can be associated with different types of lesion to different stages in SERR. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
On the impact of mood on behavior: An integrative theory and a review.   总被引:1,自引:0,他引:1  
Empirical evidence for effects of moods (both naturally occurring and experimentally manipulated) on behavior is reviewed in terms of an integrative theory: the mood-behavior model (MBM). It is posited that moods can influence behavior via 2 processes: (a) by informational effects on behavior-related judgments and appraisals, which in turn will result in behavioral adjustments (i.e., the informational mood impact on behavior), and (b) by influencing behavioral preferences and interests in compliance with a hedonic motive (i.e., the directive mood impact on behavior). The strength of the informational mood impact depends on moods' effective informational weight for behavior-related judgments and on mood-primed associations. The strength of the directive mood impact is predicted to be jointly determined by 2 variables: the strength of a hedonic motive and the instrumentality of possible acts for affect regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
The transformation behavior of near-equiatomic NiTi containing 0, 10, and 20 vol pct TiC particulates is investigated by dilatometry. Undeformed composites exhibit a macroscopic transformation strain larger than predicted when assuming that the elastic transformation mismatch between the matrix and the particulates is unrelaxed, indicating that the mismatch is partially accommodated by matrix twinning during transformation. The thermal recovery behavior of unreinforced NiTi which was deformed primarily by twinning in the martensite phase shows that plastic deformation by slip increases with increasing prestrain, leading to (1) a decrease of the shape-memory strain on heating, (2) an increase of the two-way shape-memory strain on cooling, (3) a widening of the temperature interval over which the strain recovery occurs on heating, and (4) an increase of the transformation temperature hysteresis. For NiTi composites, the recovery behavior indicates that most of the mis-match during mechanical deformation between the TiC particulates and the NiTi matrix is relaxed by matrix twinning. However, some relaxation takes place by matrix slip, resulting in the following trends with increasing TiC content at constant prestrain: (1) decrease of the shape-memory strain on heating, (2) enhancement of the two-way shape-memory strain on cooling, and (3) broadening of the transformation interval on heating. K.L. FUKAMI-USHIRO, formerly Graduate Student, Department of Materials Science and Engineering, Massachusetts Institute of Technology  相似文献   

9.
Pure democracy.     
Comments on criticism by the American Psychological Association's (APA's) Policy and Planning Board (see record 1996-09394-001) of the proposed bylaws amendment sponsored by the Committee on Representational Equity. The essence of the amendment is that each of APA's governance units on the Council of Representatives have proportional representation, which is the purest form of democracy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
The authors examined the interplay of personality and cultural factors in the prediction of the affective (hedonic balance) and the cognitive (life satisfaction) components of subjective well-being (SWB). They predicted that the influence of personality on life satisfaction is mediated by hedonic balance and that the relation between hedonic balance and life satisfaction is moderated by culture. As a consequence, they predicted that the influence of personality on life satisfaction is also moderated by culture. Participants from 2 individualistic cultures (United States, Germany) and 3 collectivistic cultures (Japan, Mexico, Ghana) completed measures of Extraversion, Neuroticism, hedonic balance, and life satisfaction. As predicted, Extraversion and Neuroticism influenced hedonic balance to the same degree in all cultures, and hedonic balance was a stronger predictor of life satisfaction in individualistic than in collectivistic cultures. The influence of Extraversion and Neuroticism on life satisfaction was largely mediated by hedonic balance. The results suggest that the influence of personality on the emotional component of SWB is pancultural, whereas the influence of personality on the cognitive component of SWB is moderated by culture. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
P. L. Breuer  M. I. Jeffrey   《Hydrometallurgy》2003,70(1-3):163-173
Due to the increasing environmental and public concerns associated with cyanide leaching of gold, much of the current research in gold hydrometallurgy is focussed on alternative systems, such as thiosulfate. One of the major problems with the thiosulfate leaching system is the undesirable reaction between thiosulfate and copper(II). The current paper presents a study on the effect of various anions on the rate of this reaction. It will be shown that the presence of anions such as sulfate, chloride and phosphate significantly reduce the rate at which copper(II) is reduced by thiosulfate. The presence of other oxysulfur species such as sulfite, tetrathionate and trithionate were also studied. These species were found to be readily oxidised by copper(II) and hence greatly increased the rate of copper(II) reduction. The rate of copper(II) reduction by tetrathionate is relatively unaffected by the addition of anions; however, anion addition was found to significantly influence the rate of copper(II) reduction by sulfite and trithionate. Based on these results, inner sphere mechanisms were proposed for the reaction of copper(II) with thiosulfate, sulfite and trithionate. The kinetics of copper(II) reduction is thus very complex and can be represented by a number of parallel-series reaction sequences.  相似文献   

12.
The transmission of forces between the visceral and parietal pleural is modelled as being mediated by two distinct pathways: (a) a contact pressure (Pcon) acting on an area of contact (Acon) and (2) a pleural liquid pressure (Pliq) acting on the area of liquid anfractuosities (Aliq). Summation of the forces yields a new equation relating pleural surface pressure (Ppl) to Pcon, Acon, Pliq, and Aliq. A complete solution of the equation is restricted by present limitations on measurement technology. However, assuming that the volume of pleural liquid is constant during tidal breathing, analysis of the model explains the findings that tidal swings in Pliq (deltaPliq) are sometimes greater than tidal swings in Ppl (deltaPpl). It also predicts that the influence of a change of lung elastic recoil on Pliq may be different in magnitude than its effect on Ppl. Therefore deltaPliq is not necessarily equivalent to deltaPpl.  相似文献   

13.
Au(CN)2^—极谱分析的研究   总被引:1,自引:1,他引:0  
吕虹辉 《黄金》1993,14(12):44-47
本文采用极谱分析的方法分析Au(CN)2-络离子的浓度,并通过Au(CN)2-在滴汞电极上电化学行为的研究,认为Au(CN)2-在滴汞电极上的还原反应为不可逆反应,而且反应是受扩散步聚控制的。  相似文献   

14.
Staurosporine (STAR) is one of the most potent inhibitors of protein kinase C (PKC). It is known that in human polymorphonuclear leukocytes (PMNs), the phorbol ester-induced generation of superoxide anion (respiratory burst) is effectively inhibited by STAR in a dose-dependent manner, whereas superoxide generation induced by chemoattractants, e.g. n-formyl-methionyl-leucyl-phenylalanine (FMLP) or PAF, is regulated biphasically by STAR. We compared the effects of STAR and K252a on FMLP-induced superoxide production from PMNs and examined the effects of propranolol, a inhibitor of phosphatidic acid (PA) phosphohydrolase, on the potentiation of the production by STAR. We also examined the effects of some derivatives of STAR and K252a on the production and the alteration of the effects induced by propranolol pretreatment. When PMNs were stimulated with FMLP, STAR potentiated superoxide production by 240.5 +/- 30.9% at a low concentration (100 nmol/l). Propranolol pretreatment specifically inhibited the potentiation. When phorbol-12-myristate-13-acetate (PMA) was used as a stimulant, STAR inhibited superoxide production dose-dependently and did not enhance the production. K252a inhibited PMA or FMLP-induced superoxide production dose-dependently and did not enhance FMLP-induced superoxide production. STAR derivatives showed potentiation of FMLP-induced superoxide production similar to that of STAR at concentrations ranging from 10-100 nmol/l, and propranolol (200 mumol/l) effectively inhibited it. K252a derivative NA332 did not show any potentiative effect on the production. PMA-induced superoxide production was inhibited by all compounds dose-dependently.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
The elemental and phase composition and defect structure of the surface layer on 5140 steel is considered after alloying by melting of a film–substrate (5140 steel) system under irradiation by intense pulsed electron beam; the film consists of aluminum or titanium. Treatment of the titanium–5140 steel system results in alloying to the depth of the molten layer (about 15 μm); polycrystalline structure (with submicron grains) based on α-phase hardened by titanium-carbide nanoparticles is formed. For the aluminum–5140 steel system, only a thin surface layer (about 2 μm) is alloyed, on account of the evaporation of aluminum from the steel surface. Martensit structure hardened by iron-aluminide nanoparticles is formed.  相似文献   

16.
Kell and Kx are two quantitatively minor proteins from the human erythrocyte membrane which carry blood groups antigens and are thought to be a metalloprotease and a membrane transporter, respectively. In the red cell membrane, these proteins form a complex stabilized by disulfide bond(s). Phosphorylation status of these proteins was studied, in the presence or absence of effectors of several kinases, either on intact cells incubated with [32P]-orthophosphate or on ghosts incubated with [gamma-32P]ATP. Purification of Kell-Kx complex, by immunochromatography on an immobilized human monoclonal antibody of Kell blood group specificity allowed to establish that (i) neither protein is phosphorylated on tyrosine; (ii) the Kell protein is a putative substrate for Casein Kinase II (CKII) and Casein Kinase I (CKI) but not for protein kinase C (PKC), whereas Kx protein is phosphorylated by CKII and PKC but not by CKI; (iii) Protein Kinase A neither phosphorylates the Kell nor the Kx proteins.  相似文献   

17.
The structure and catalytic properties of the enzyme (E) chlorocatechol dioxygenase (CCD) adsorbed on a citrate-reduced silver colloid are analyzed by surface-enhanced resonance Raman spectroscopy (SERRS). This is the first SERRS study of a non-heme metalloenzyme. It is demonstrated that the native conformation of CCD is retained in the adsorbed state by comparison of resonance Raman scattering (RRS) from CCD in solution with SERRS from CCD adsorbed on the silver colloid. Both spectra show clear evidence of vibrational bands typical of iron-tyrosinate proteins. Furthermore, it is demonstrated that adsorbed CCD retains 60-85% of its enzymatic activity in the reaction of catechol substrate (S) with O2 to give the dioxygenated product (P) cis,cis-muconate. This is accomplished by enzyme assays of Ag-adsorbed CCD and comparison of the SERRS of Ag-adsorbed enzyme-substrate (ES) complex under anaerobic conditions with that of Ag-adsorbed ES in the presence of dioxygen. The SERRS difference spectrum, ES(aerobic)--ES(anaerobic), shows clear evidence for the appearance of the vibrational modes of adsorbed product. The analogous SERR difference spectroscopy experiment is also carried out for the enzyme-inhibitor (EI) complex of CCD with tetrachlorocatechol (TCC). Slow turnover of CCD-TCC is observed by SERRS on exposure to dioxygen which is consistent with the slow rate of turnover of TCC by CCD in solution.  相似文献   

18.
Comments on the article by P. A. Ornstein et al (see record 2000-13581-005) on adult recollections of childhood abuse, which is part of the report by the American Psychological Association Working Group on Investigation of Memories of Childhood Abuse (see record 2000-13581-002). Points on which they agree with Ornstein et al include the following: (1) Real occurrences and false allegations of sexual abuse are serious and potentially life-shattering for victims. (2) Memory is not perfect. (3) Remembering is facilitated by retrieval cues, contextual support, and the reexperiencing of affect similar to that which occurred at the time of an event. (4) Some people are suggestible under certain conditions. (5) Psychotherapy can be substandard, as can research. (6) When a report of memory of sexual abuse first arises in therapy, a neutral and exploratory stance by the therapist should be maintained. Points of disagreement include (1) the selective review of the memory literature, (2) the lack of attention to methodological issues, (3) the selective interpretation of the literature and the resultant drawing of implications, and (4) a serious misunderstanding of some of the concepts under discussion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Comments on the series on managed health care (MHC) edited by R. L. Lowman (see record 1991-16482-001) that advocated restrictions in MHC to reduce employer costs. It is argued that restricting outpatient coverage is not mandated by economic necessity, and that it creates ethical and clinical risks and ill will toward funders by patients and therapists. Alternative MHC services are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
The CP-I subunit of calf kidney adenosine deaminase complexing protein (ADCP), isolated by affinity chromatography based on Sepharose-4B immobilized adenosine deaminase, is identical with dipeptidyl peptidase IV. This finding is based on the following results: (a) Its M(r) = 110 kD, as determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis; (b) its catalytic activity toward Gly-Pro-p-nitroanilide; (c) its inhibition by serine protease inhibitor; and (d) by two peptide sequences resulting from its trypsin proteolysis. Accordingly, the CP-I subunit of ADCP isolated from bovine kidney is DPPIV (CD26). Thus, as anticipated, the high affinity between ADA subunits prevails even when they originate in different species.  相似文献   

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