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101.
In Study 1, 12 undergraduates informed only of the normal physiological reactions to hand immersion in cold water and 12 Ss informed that they were participating in a "study of the perception of novel stimuli" showed much greater tolerance and reported significantly less pain than did 12 controls given no pretesting message. Therefore, giving Ss the chance to ascribe uncomfortable sensations to a nondamaging process increased tolerance. Study 2, with 5 graduate students, showed that repeated exposure to cold-water immersion (employed to demonstrate safety of the procedure) did not reduce the reported sensation of pain, indicating that the increased tolerance following assurances of safety was directly due to decreased threat and not to decreased sensation. Findings support the distinction between pain sensation and emotional-motivational reaction leading to escape or avoidance. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
IS planning has changed considerably since its inception as an operational planning tool, expanding its scope to address key business objectives and forging a link with strategic business planning. A great deal of attention is currently focused on identifying and developing strategic information systems. Strategic planning has also become more broadly-focused over time, as simple forecasting techniques have been replaced by a variety of adaptive approaches that emphasize industry structure analysis and environmental dynamics. However, strategic planning has come under fire recently for failing to live up to its promises. As these two disciplines become more closely aligned, planners can learn from the experiences of strategic planners and, hopefully, avoid a similar crisis of confidence.  相似文献   
103.
The assembly of multifunctional nanocomposite materials is demonstrated by exploiting the molecular sieving property of SBA‐16 nanoporous silica and using it as a template material. The cages of the pore networks are used to host iron oxide magnetic nanoparticles, leaving a pore volume of 0.29 cm3 g?1 accessible for drug storage. This iron oxide–silica nanocomposite is then functionalized with amine groups. Finally the outside of the particle is decorated with antibodies. Since the size of many protein molecules, including that of antibodies, is too large to enter the pore system of SBA‐16, the amine groups inside the pores are preserved for drug binding. This is proven using a fluorescent protein, fluorescein‐isothiocyanate‐labeled bovine serum albumin (FITC‐BSA), with the unreacted amine groups inside the pores dyed with rhodamine B isothiocyanate (RITC). The resulting nanocomposite material offers a dual‐targeting drug delivery mechanism, i.e., magnetic and antibody‐targeting, while the functionalization approach is extendable to other applications, e.g., fluorescence–magnetic dual‐imaging diagnosis.  相似文献   
104.
The present study compared the role of life events in predicting time to index episode onset under conditions of no or variable treatment versus the role of life events in predicting time to recurrence during maintenance interpersonal psychotherapy (IPT). Eighty-three women with recurrent major depression participated in acute IPT treatment followed by 2 years of maintenance IPT. Life events were assessed using contextual interview and rating methods. Cox regression survival analyses indicated that, although severe life events were significantly associated with time to index episode onset, there was little evidence of an association between events experienced during maintenance treatment and time to recurrence. These results provide evidence that IPT may decrease the potency of life events in provoking recurrence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Transreac is a computer model for the simulation of the chemical attack to which mineral building materials are exposed. For reliability analysis, Transreac is used in conjunction with the Monte Carlo simulation method. The probabilistic model was evaluated for cement mortar corroded as a result of sulfate attack. The experimentally derived corrosion effects and their scatter are in good agreement with simulation results. In addition, the probability of failure was predicted and a sensitivity analysis was performed.  相似文献   
106.
We conducted three experiments to assess the hypothesis that mindlessness could be prevented with a simple linguistic variation. Subjects in the first two experiments were either introduced to new objects conditionally (e.g., this could be an X) or unconditionally (e.g., this is an X), and the objects used were either unfamiliar or familiar. In each study a different need was then generated for which the object in question was not explicitly suited but could fulfill. Only those subjects in the conditional-unfamiliar group gave the creative response and met the need. When subjects were asked explicitly to generate novel uses for the target items, they had no difficulty doing so. However, given the way we are traditionally taught, it simply does not occur to us to think creatively unless explicitly instructed to do so. In the third experiment we introduced an unfamiliar item in one of three ways. In addition to the groups used in the earlier experiments, we added a group that was led to believe that the object was identifiable (unconditional) but was currently unknown. We also added a second need to determine whether the original conditional group truly learned conditionally or if they were in search of an absolute understanding of the target object. Significantly more of the subjects in the conditional group gave the creative response to both needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
In this paper we present algorithms for solving some combinatorial problems on one-dimensional processor arrays in which data flows in only one direction through the array. The problems we consider are: ranking the elements in a chain of sizen, rooting a spanning tree withn vertices, and computing biconnected components of a connected graph withn vertices. We show that each of these problems can be solved using arrays of sizen in which the data enters at the first cell and flows through the array in only one direction until it leaves the last cell as output. We also show how the biconnectivity algorithm for the array yields a new sequential algorithm for computing biconnected components which uses onlyO(n) locations of random access memory.  相似文献   
108.
Preschool children bilingual in English and Hebrew were investigated for their understanding of concepts of print by means of two tasks. In the first, children had to understand that a printed word did not change its meaning if it moved to a new location. In the second, children had to make judgments about word length and ignore the size of the named objects. Previous research had shown bilingual French–English and Chinese–English children to excel in the first task, but only older Chinese–English bilinguals had an advantage in the second. The present study extended those results by investigating the effect of writing system in more detail. The study also examined the effect of the language of the environment by conducting parallel studies in environments in which either English or Hebrew was the community language. The results show that the bilingual children in both settings were more advanced than the monolinguals in both tasks and in both settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
This study evaluated secondary prevention approaches for young adults (N?=?36, mean age 23 yrs) at risk for alcohol problems. Ss were randomly assigned to cognitive-behavioral alcohol skills training, a didactic alcohol information program, or assessment only. The skills program included training in blood alcohol level estimation, limit setting, and relapse prevention skills. All Ss maintained daily drinking records during the 8-wk intervention and for 1 wk at each follow-up. Repeated measures multivariate analysis of variance (MANOVA) found a significant reduction over 1-yr follow-up in self-reported alcohol consumption for the total sample. For all drinking measures, the directional findings consistently favored skills training. Despite overall reductions, most Ss continued to report occasional heavy drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Sodium chlorite (SC) is an effective sanitizer for inhibiting microbial growth. This investigation was conducted to determine the efficacy of SC as a browning control agent for use on fresh-cut apple slices, applied alone, or in conjunction with organic acids. Additionally, the authors compared the efficacy of SC to that of acidified sodium chlorite (ASC) and to several other salts and examined the effect of pH and several different organic acids on efficacy of SC. The fresh-cut apple slices were dipped in treatment solutions for 1 min, then drained and placed in plastic containers at 20 °C for 24 h, and finally stored in polyethylene bags at 5 °C for 2 weeks. Color was measured periodically during storage. Lightness (L) values for all treated and control samples measured at 4 h, 24 h, and 2 weeks of storage were compared to L value for untreated samples measured immediately after cutting. Percent decrease in L-values was calculated for each sample at each time interval. Apple slices treated in ASC or SC solution had a significantly smaller decrease in L value indicating less browning than those treated in citric acid or water control at 4 h (P < 0.01), and with the exception of 1 g L−1 ASC and 0.1 g L−1 SC, all other ASC and SC treated slices still had significantly less browning than those for the water control (P < 0.01) at 24 h. After 2 weeks of storage, only SC (0.5–1.0 g L−1), sodium bisulfite (0.5 g L−1) and calcium l-ascorbate (10 g L−1) continued to inhibit browning. Treatment with 0.5 g L−1 SC and pH adjusted in the range from 3.9 to 6.2 using citric acid (CA) reduced browning more effectively than 0.5 g L−1 SC without pH adjustment. Two organic acids, salicylic acid and cinnamic acid, when added to SC solution, were found to achieve even better inhibition of browning than CA at the same pH value.  相似文献   
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