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101.
In two studies, we examined depressed and nondepressed persons' judgments of the probability of future positive and negative life events occurring to themselves and to others. Study 1 demonstrated that depressed subjects were generally less optimistic than their nondepressed counterparts: Although nondepressed subjects rated positive events as more likely to happen to themselves than negative events, depressed subjects did not. In addition, relative to nondepressed subjects, depressed subjects rated positive events as less likely to occur to themselves and more likely to occur to others and negative events as more likely to occur to both self and others. Study 2 investigated the role that differential levels of self-focused attention might play in mediating these differences. On the basis of prior findings that depressed persons generally engage in higher levels of self-focus than nondepressed persons do and the notion that self-focus activates one's self-schema, we hypothesized that inducing depressed subjects to focus externally would attenuate their pessimistic tendencies. Data from Study 2 supported the hypothesis that high levels of self-focus partially mediate depressive pessimism: Whereas self-focused depressed subjects were more pessimistic than nondepressed subjects, externally focused depressed subjects were not. The role of attentional focus in maintaining these and other depressive pessimistic tendencies was discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Amphiphilic TiO2 nanotube arrays (TiO2 NTs) were fabricated through electrochemical oxidation of Ti in solution containing H3PO4 and NaF. Scanning electron microscopic analysis shows that the as-prepared TiO2 NTs have an average pore diameter of 100 nm and a wall thickness of 15 nm. The electrochemical oxidation of Ti can be divided into four stages. In the first stage, when the potential is very low, oxygen formation and Ti dissolution are the major reactions. The second stage corresponds to a slightly higher potential, but less than 2.5 V. In this stage, the formation of TiO2 film occurs. When the potential is increased to the even higher range from 2.5 V to 6 V, the TiO2 film dissolves and nanoporous surface structure is generated. This is the third stage. Further increase of the potential enters stage four. The high potentials cause the self-organization of the nanostructure and allow the formation of well-aligned TiO2 NTs. We also found that the change in surface condition of Ti by annealing heat treatment affects the film dissolution kinetics. As compared with TiO2 thin film, the TiO2 NTs show higher photocatalytic activity on decomposing Rhodamine B. The surface of the TiO2 NTs can be wetted by both water and oil. Such an amphiphilic property comes from the capillary effect of the nanochannel structure of the TiO2 NTs. Because of the amphiphilic property and the photocatalytic activity, we conclude that the TiO2 NTs have the capability of self-cleaning. 相似文献
104.
Nitric oxide (NO) has been proposed as an intercellular messenger mediating postsynaptic to presynaptic information transfer in the induction of long-term potentiation. A number of studies support the possible involvement of NO in synaptic plasticity. NO may have a role in synaptogenesis and synaptic plasticity in developing rat brain and may play a fundamental part in the process of regeneration, plasticity, and retargeting of axons following injury. We examined the possible role of NO on plasticity in the rat first somatosensory cortex with [14C]2-deoxyglucose (2-DG) autoradiography in rats treated daily with l-nitroarginine (l-NA) following neonatal unilateral vibrissae deafferentation. After 6 weeks of l-NA treatment, the local cerebral glucose utilization (LCGU) and the spatial extent of the metabolic activation following stimulation of the spared whisker was measured. NOS catalytic activity exhibited significant inhibition throughout the treatment period. Vibrissae deafferentation produced a small but not statistically significant increase of LCGU in the vibrissa activated C3 barrel, and l-NA treatment did not alter the activation of LCGU in the deafferented cortex following whisker stimulation. Additionally, l-NA treatment did not alter the area of metabolic activation on either the non-deafferented side or the deafferented side. Deafferentation produced a 298% increase in the metabolic representation of the spared C3 barrel following stimulation in the saline treated animals, a 257% increase in the chronically l-NA treated animals, and a 256% increase in the short-term treated animals, all with respect to the response in the non-deafferented cortex. Metabolic plasticity in the barrel cortex was not attenuated by l-NA treatment. These results show that nitric oxide does not play a major role on developmental cortical plasticity induced by vibrissae deafferentation in the rat. 相似文献
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106.
Berent Iris; Balaban Evan; Lennertz Tracy; Vaknin-Nusbaum Vered 《Canadian Metallurgical Quarterly》2010,139(3):418
Domain-specific systems are hypothetically specialized with respect to the outputs they compute and the inputs they allow (Fodor, 1983). Here, we examine whether these 2 conditions for specialization are dissociable. An initial experiment suggests that English speakers could extend a putatively universal phonological restriction to inputs identified as nonspeech. A subsequent comparison of English and Russian participants indicates that the processing of nonspeech inputs is modulated by linguistic experience. Striking, qualitative differences between English and Russian participants suggest that they rely on linguistic principles, both universal and language-particular, rather than generic auditory processing strategies. Thus, the computation of idiosyncratic linguistic outputs is apparently not restricted to speech inputs. This conclusion presents various challenges to both domain-specific and domain-general accounts of cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Manring John; Greenberg Roger P.; Gregory Robert; Gallinger Lisa 《Canadian Metallurgical Quarterly》2011,48(2):119
There is substantial literature documenting the process factors that lead to effective psychotherapy. Similarly, there is now a wealth of data attesting to the effectiveness of several psychotherapy brands. Little is known about the elements that facilitate learning how to be an effective clinician. One important step, after reading about a treatment model and seeing techniques demonstrated, is having the chance to practice the approach and receiving feedback and coaching from an experienced, knowledgeable supervisor. To accomplish this efficiently, most programs rely not only on trainee accounts of what went on in their therapy sessions, but also on recordings and videos of therapeutic encounters. This article describes our experience over a 5-year period in developing the use of Webcams for training psychology interns and psychiatric residents in the delivery of psychotherapy services. Pragmatic and technical details are given about how we went about establishing a recording system that is easy to use and provides secure, confidential storage of information at a reasonable cost. Discussion addresses both the weighing of choices that need to be made and overcoming the hesitation of trainees to reveal their work during treatment sessions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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109.
This investigation identifies that Mauribrew Lager 497 strain of dried yeast can be used as a standard strain for the determination of malt apparent attenuation limit (AAL). It provides ferment‐ability results for malt quality evaluation laboratories that are comparable to fresh brewery yeast. It was found that the optimal pitching rate in Congress wort (EBC Analytica, 1998, method 4.5.1), was 1 g per 200 mL, pitched at 25°C and fermented for 24 h at 20°C with agitation to complete attenuation. Preliminary trials also indicated that the Mauribrew Lager 497 dry yeast may be useful to brewers for determining the wort batch attenuation characteristics by the limit gravity test. In this case a pitching temperature of 35°C was found to be optimal with all other conditions as above. For the purpose of malt quality evaluation and brewery quality control the advantages of using a standard dry yeast strain include ease and convenience of use, consistency of quality, and uniformity between laboratories when they are located in separate geographic regions. 相似文献
110.
Harmon-Jones Eddie; Simon Linda; Greenberg Jeff; Pyszczynski Tom; Solomon Sheldon; McGregor Holly 《Canadian Metallurgical Quarterly》1997,72(1):24
On the basis of the terror management theory proposition that self-esteem provides protection against concerns about mortality, it was hypothesized that self-esteem would reduce the worldview defense produced by mortality salience (MS). The results of Exps 1 (49 undergraduates) and 2 (50 undergraduates) confirmed this hypothesis by showing that individuals with high self-esteem (manipulated in Exp 1; dispositional in Exp 2) did not respond to MS with increased worldview defense, whereas individuals with moderate self-esteem did. The results of Exp 3 (48 undergraduates) suggested that the effects of the 1st 2 experiments may have occurred because high self-esteem facilitates the suppression of death constructs following MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献