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991.
992.
Inlet ionization is a new approach for ionizing both small and large molecules in solids or liquid solvents with high sensitivity. The utility of solvent based inlet ionization mass spectrometry (MS) as a method for analysis of volatile and nonvolatile compounds eluting from a liquid chromatography (LC) column is demonstrated. This new LC/MS approach uses reverse phase solvent systems common to electrospray ionization MS. The first LC/MS analyses using this novel approach produced sharp chromatographic peaks and good quality full mass range mass spectra for over 25 peptides from injection of only 1 pmol of a tryptic digest of bovine serum albumin using an eluent flow rate of 55 μL min(-1). Similarly, full acquisition LC/MS/MS of the MH(+) ion of the drug clozapine, using the same solvent flow rate, produced a signal-to-noise ratio of 54 for the major fragment ion with injection of only 1 μL of a 2 ppb solution. LC/MS results were acquired on two different manufacturer's mass spectrometers using a Waters Corporation NanoAcquity liquid chromatograph. 相似文献
993.
Raskin Sarah A.; Woods Steven Paul; Poquette Amelia J.; McTaggart April B.; Sethna Jim; Williams Rebecca C.; Tr?ster Alexander I. 《Canadian Metallurgical Quarterly》2011,25(2):201
Objective: The aim of the current study was to clarify the nature and extent of impairment in time- versus event-based prospective memory in Parkinson's disease (PD). Prospective memory is thought to involve cognitive processes that are mediated by prefrontal systems and are executive in nature. Given that individuals with PD frequently show executive dysfunction, it is important to determine whether these individuals may have deficits in prospective memory that could impact daily functions, such as taking medications. Although it has been reported that individuals with PD evidence impairment in prospective memory, it is still unclear whether they show a greater deficit for time- versus event-based cues. Method: Fifty-four individuals with PD and 34 demographically similar healthy adults were administered a standardized measure of prospective memory that allows for a direct comparison of time-based and event-based cues. In addition, participants were administered a series of standardized measures of retrospective memory and executive functions. Results: Individuals with PD demonstrated impaired prospective memory performance compared to the healthy adults, with a greater impairment demonstrated for the time-based tasks. Time-based prospective memory performance was moderately correlated with measures of executive functioning, but only the Stroop Neuropsychological Screening Test emerged as a unique predictor in a linear regression. Conclusions: Findings are interpreted within the context of McDaniel and Einstein's (2000) multiprocess theory to suggest that individuals with PD experience particular difficulty executing a future intention when the cue to execute the prescribed intention requires higher levels of executive control. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
994.
Two experiments examined parafoveal preview for words located in the middle of sentences and at sentence boundaries. Parafoveal processing was shown to occur for words at sentence-initial, mid-sentence, and sentence-final positions. Both Experiments 1 and 2 showed reduced effects of preview on regressions out for sentence-initial words. In addition, Experiment 2 showed reduced preview effects on first-pass reading times for sentence-initial words. These effects of sentence position on preview could result from either reduced parafoveal processing for sentence-initial words or other processes specific to word reading at sentence boundaries. In addition to the effects of preview, the experiments also demonstrate variability in the effects of sentence wrap-up on different reading measures, indicating that the presence and time course of wrap-up effects may be modulated by text-specific factors. We also report simulations of Experiment 2 using version 10 of E-Z Reader (Reichle, Warren, & McConnell, 2009), designed to explore the possible mechanisms underlying parafoveal preview at sentence boundaries. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
995.
Klein Daniel N.; Leon Andrew C.; Li Chunshan; D'Zurilla Thomas J.; Black Sarah R.; Vivian Dina; Dowling Frank; Arnow Bruce A.; Manber Rachel; Markowitz John C.; Kocsis James H. 《Canadian Metallurgical Quarterly》2011,79(3):342
Objective: Depression is associated with poor social problem solving, and psychotherapies that focus on problem-solving skills are efficacious in treating depression. We examined the associations between treatment, social problem solving, and depression in a randomized clinical trial testing the efficacy of psychotherapy augmentation for chronically depressed patients who failed to fully respond to an initial trial of pharmacotherapy (Kocsis et al., 2009). Method: Participants with chronic depression (n = 491) received cognitive-behavioral analysis system of psychotherapy (CBASP; McCullough, 2000), which emphasizes interpersonal problem solving, plus medication; brief supportive psychotherapy (BSP) plus medication; or medication alone for 12 weeks. Results: CBASP plus pharmacotherapy was associated with significantly greater improvement in social problem solving than BSP plus pharmacotherapy, and a trend for greater improvement in problem solving than pharmacotherapy alone. In addition, change in social problem solving predicted subsequent change in depressive symptoms over time. However, the magnitude of the associations between changes in social problem solving and subsequent depressive symptoms did not differ across treatment conditions. Conclusions: It does not appear that improved social problem solving is a mechanism that uniquely distinguishes CBASP from other treatment approaches. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
996.
Solmeyer Anna R.; Killoren Sarah E.; McHale Susan M.; Updegraff Kimberly A. 《Canadian Metallurgical Quarterly》2011,25(2):251
In this study we examined patterns of mothers' and fathers' differential affection and discipline toward 2 adolescent offspring in 243 Mexican-origin families. Grounding our work in a family systems perspective, we used interparental patterns of differential treatment as an index of the coparental alliance and tested their associations with parents' reports of familism values, traditional gender role attitudes, and cultural orientations. We also sought to replicate prior research on European American samples linking interparental patterns of differential treatment to marital qualities (coparenting satisfaction, love, and conflict) and adolescent depressive symptoms and risky behaviors. Three interparental patterns emerged: families in which both mothers and fathers treated their 2 offspring equally, incongruent families in which 1 parent treated both offspring equally while the other parent favored 1 offspring, and congruent families in which both parents favored the same offspring. Most parents reported equal treatment, but others fell into the incongruent affection (30%), incongruent discipline (45%), and congruent discipline (16%) groups. Mixed model analyses of variances revealed that in families in which mothers and fathers both treated their offspring equally, parents reported higher familism values, more traditional gender role attitudes, and relatively stronger orientations to Mexican than Anglo culture. Consistent with previous research, interparental incongruence was associated with less positive marital qualities and more adolescent adjustment problems. Discussion focuses on the role of culture in shaping coparenting and the processes through which these coparenting dynamics are linked to marital and youth adjustment. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
997.
Current theories of category learning posit separate verbal and nonverbal learning systems. Past research suggests that the verbal system relies on verbal working memory and executive functioning and learns rule-defined categories; the nonverbal system does not rely on verbal working memory and learns non-rule-defined categories (E. M. Waldron & F. G. Ashby, 2001; D. Zeithamova & W. T. Maddox, 2006). However, relatively little research has explored the importance of visual working memory or visual processing for either system. The authors investigated the role of working memory (Experiment 1a and 1b), visual processing (Experiment 2), and executive functioning for each system, using a concurrent task methodology. It was found that visual tasks with high executive functioning demands and verbal tasks with high or low executive demands disrupted rule-defined learning, whereas any visual task, regardless of executive functioning demand, disrupted non-rule-defined learning. Taken together, these results confirm the importance of verbal working memory and executive functioning for the verbal system and provide new evidence for the importance of visual processing for the nonverbal system. These results help to clarify understanding of the nonverbal system and have implications for multiple systems theories of category learning (F. G. Ashby, L. A. Alfonso-Reese, A. U. Turken, & E. M. Waldron, 1998). (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
998.
Shamey R Shepherd S Abed M Chargualaf M Garner N Dippel N Weisner N Kuehni RG 《Journal of the Optical Society of America. A, Optics, image science, and vision》2011,28(10):1962-1969
The aim of this study was to determine how accurately color-normal subjects that have received basic information about, but do not have practical experience with, the Natural Color System (NCS) can estimate the Heringian components of a representative selection of samples. Twenty-five color-normal subjects, taking part in two trials with at least a 24 h gap between assessments, selected four samples representing individual unique hues (uHs) from a set of 40 highly chromatic NCS samples on a rotatable tray. The samples selected for assessment of components were displayed to the subjects who estimated the hue components of 16 high-chroma samples, hue and white/black components of 16 tonal color samples, and three achromatic samples with different blackness values. Variability in selection of samples representing uHs as well as the relationship between the subjects' estimates of unique hue components and the defined values of the system was obtained. It was found that hues alone are easier to correctly estimate than hues together with white and black and that the components of colors of higher chroma are easier to estimate accurately than those of lower chroma. It was also found that, for R and G, the mean uH choices of subjects differed very little from the NCS's R and G, whereas selections for yellow and blue deviated, the former by 1.22 hue steps (slightly greener than G90Y), and the latter by 1.36 hue steps (represented approximately by R85B). This may impact the accuracy of color models that employ NCS unique hues. 相似文献
999.
1000.
Sarah Bell 《The International journal of environmental studies》2013,70(5):581-589
Analysis of press reports of the onset of drought in Sydney in 2002 and London in 2006 shows different understandings of the relationship between infrastructure provision, individual behaviour and the environment. Drought is both a natural and cultural phenomenon requiring urban water managers to consider social as well as technical considerations in preparing for future droughts. 相似文献