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71.
Thomas S Marzilli Kristin Florence Willhoit Mark Guadagnoli 《Nicotine & tobacco research》2006,8(3):425-433
Recent evidence has indicated that nicotine, the active agent in tobacco, may affect mental abilities of smokers. To better understand the effects of nicotine on central processing, we used a basic chronometric approach to studying information processing. This chronometric approach allowed for the independent examination of nicotine's effects on two theoretically nonoverlapping information-processing stages, stimulus identification and response programming. Two stimulus intensity and four distance traversed conditions were used to affect the stimulus identification and response programming stages, respectively. The 11 subjects completed two experimental sessions (nicotinized and denicotinized), which were conducted 1 week apart. Each experimental session comprised two tests. The first test consisted of abstinent baseline measures, and the second test was administered after subjects smoked an investigator-supplied nicotinized or denicotinized cigarette. Data analysis revealed that the higher intensity stimulus elicited faster reaction times, as did the shorter movement distances, thus confirming successful manipulation of both the stimulus identification and response programming stages of the information-processing model. Furthermore, the significant improvement in reaction-time performance over baseline abstinent levels was consistent despite the manipulations made within the stimulus identification stage of processing, demonstrating that no interaction existed between stimulus intensity and the administration of nicotine. Interestingly, these data provide initial evidence that although nicotine may not affect the programming of very simple movements, it has a more pronounced effect on more complex movements. Although distance traversed had a reliable effect on movement time, nicotine had no observable effect. 相似文献
72.
Koetting O'Byrne Kristin; Peterson Lizette; Saldana Lisa 《Canadian Metallurgical Quarterly》1997,16(2):147
A survey of all 123 nonchronic-care pediatric hospitals in the United States revealed that 75% of hospitals responding had greatly increased the use of effective medical procedure preparation technologies, such as filmed modeling and coping skills instruction, in comparison to the last survey. Respondent characteristics such as position (e.g., nurse, child life worker, physician), degree (e.g., RN, MA, PhD), and length of time in the position failed to predict the type of techniques selected, but higher respondent knowledge and more psychological sources of preparation information did predict the use of preparation techniques used for drawing blood that experts rated as more effective. Challenges for more effective dissemination of research in the future are considered, as is the need for increased study of research implementation links. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
The present study extends the literature base that is answering the call to examine the validity of J. L. Holland's (1959, 1997) 6 types of themes (realistic [R], investigative [I], artistic [A], social [S], enterprising [E], and conventional [C]) in his typology when applied to populations that are culturally different from the populations with whom the typology was developed. Native Hawaiians (N=156), a group not previously investigated, completed a personal demographics form and the Strong Interest Inventory (L. W. Harmon, J. C. Hansen, F. H. Borgen, & A. L. Hammer, 1994). The construct validity of Holland's typology was supported in that Holland's vocational interest types were arranged in a circular R-I-A-S-E-C order. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Clinical and some epidemiological data conflict concerning the likelihood of suicide attempt in individuals with panic disorder (PD). The purpose of this study was to illuminate the panic disorder-suicide attempt association in the National Comorbidity Survey (NCS; R. C. Kessler et al., 1994). Specifically, suicide attempt histories of those 5,872 respondents answering "yes" or "no" to the suicide attempt question were regressed against lifetime diagnostic histories. Lifetime PD history, in the presence of other disorders, was unrelated to elevated risk of suicide attempt and did not account for additional variance. PD respondents who had made a suicide attempt were characterized by Comorbidity. Epidemiological respondents with lifetime histories of PD alone are not at heightened risk for self-reported suicide attempt. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
The authors applied I-States as Objects Analysis (ISOA), a recently proposed person-oriented analytic approach, to the study of temperament development in 921 Norwegian children from a population-based sample. A 5-profile classification based on cluster analysis of standardized mother reports of activity, sociability, emotionality, and shyness at ages 18 months, 30 months, 4-5 years, and 8-9 years was interpretable and highly replicable. The prevalence of temperament profiles changed markedly with age, and individual stability in temperament profiles was significant. Specific typical and atypical developmental sequences of profiles were identified. Selective patterns of concurrent group differences in externalizing and internalizing problems by temperament profiles were remarkably similar across ages. The findings to some degree support the notion that individual temperament-variable values take on meaning in relation to the whole individual configuration and indicate some lawfulness in temperament changes over time. Future person-oriented studies of temperament development should replicate the current results using multiple data sources, rigorous tests of gender differences, and latent group modeling. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
New products drive business. To remain competitive, industry is continually searching for new methods to evolve their products.
To address this need, we introduce a new reverse engineering and redesign methodology. We start by formulating the customer
needs, followed by reverse engineering, creating a functional model through teardowns. The functional model leads to specifications
that match the customer needs. Depending upon required redesign scope, new features are possibly conceived, or not. Next,
models of the specifications are developed and optimized. The new product form is then built and further optimized using designed
experiments. An electric wok redesign provides an illustration. The methodology has had a positive impact on results by using
a systematic approach, both within design education and industrial applications. 相似文献
77.
78.
40 3rd and 5th graders were administered the 1st 3 dilemmas of Kohlberg's Moral Judgment Scale. One group received the scale 2 wks after first administration, while another group received a multiple-choice variant of the scale. Data analyses revealed low test–retest reliability for scores attained on the 3 dilemmas together as well as individually. Scores on items within each dilemma were found to be low and generally nonsignificant. Ss who received the multiple choice variant of the scale scored at significantly higher moral levels than did those who received the typical verbal production version of the scale. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Fourier transform ion cyclotron resonance (FTICR) mass spectrometry represents a unique platform with which to study nucleic acids and non-covalent complexes containing nucleic acids moieties. In particular, systems in which very high mass measurement accuracy is required, very complex mixtures are to be analyzed, or very limited amounts of sample are available may be uniquely suited to interrogation by FTICR mass spectrometry. Although the FTICR platform is now broadly deployed as an integral component of many high-end proteomics-based research efforts, momentum is still building for the application of the platform towards nucleic acid-based analyses. In this work, we review fundamental aspects of nucleic acid analysis by FTICR, focusing primarily on the analysis of DNA oligonucleotides but also describing applications related to the characterization of RNA constructs. The goal of this review article is to give the reader a sense of the breadth and scope of the status quo of FTICR analysis of nucleic acids and to summarize a few recently published reports in which researchers have exploited the performance attributes of FTICR to characterize nucleic acids in support of basic and applied research disciplines including genotyping, drug discovery, and forensic analyses. 相似文献
80.
Minh Van Nguyen Sigurjon Arason Kristin Anna Thorarinsdottir Gudjon Thorkelsson Agusta Gudmundsdóttir 《Journal of food engineering》2010
The influence of different salt concentrations of 6%, 15%, 18% and 24% (w/w) on mass transfer of water and salt during brine salting of cod loins was studied. An increase in salt concentration accelerated water exudation and salt diffusion in the cod loins. Weight gain of the cod loins increased with decreasing salt concentration and the cod loins in the 6% brine had the highest process yield. The salting kinetic parameter values for total and water weight changes decreased with increasing salt concentration. Inversely, higher salting kinetic parameter values for salt weight changes were observed for higher brine concentrations. The samples brined at 18% and 24% had identical effective diffusion coefficients and the highest effective diffusion value was found in the cod loins brined at 15%. 相似文献