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111.
Stearidonic acid (SDA, 18:4 ω-3) content of modified soybean oil (MSO) containing?~25?% SDA, was increased by lipase-catalyzed hydrolysis. Four non-immobilized powdered lipases, Lipase AY 30 (Candida rugosa), Lipase G 50 (Penicillium camembertii), Lipomod? 34P-L034P (Candida cylindracea [rugosa]), Lipomod? 36P-L036P (Rhizopus oryzae), and an immobilized lipase, Lipozyme RM IM (Rhizomucor miehei) were assessed, at various incubation times, for their ability to hydrolyze MSO and specificity toward SDA. The SDA enriched products contained triacylglycerols (TAG), diacylglycerols (DAG) and monoacylglycerols (MAG). Lipase 34P-L034P exhibited specificity towards SDA, while Lipase AY was able to discriminate against it. The highest total SDA content (40.9?mol%) was obtained with Amano AY lipase at 4?h incubation (66.2?% hydrolysis). Unhydrolyzed TAG, 1,3-DAG, 2,3(1)-DAG, and MAG contained 37.7 (56.4 at the sn-2 position), 41.6, 51.5 (54.9 at the sn-2 position), and 49.9?% SDA, respectively. Amano AY lipase was also used to hydrolyze previously SDA-enriched TAG (48.7?% SDA) obtained from low temperature crystallization of MSO. The highest total SDA content (62.7?mol%) was obtained at 12?h incubation (85.9?% hydrolysis). The SDA contents of unhydrolyzed TAG, 1,3-DAG, 2,3(1)-DAG, and MAG were 58.7 (65.7 at the sn-2 position), 71.2, 70.2 (52.9 at the sn-2 position), and 59.4?%, respectively.  相似文献   
112.
We investigated how prior knowledge influences the amount of short-term nonverbal and verbal memory and long-term retention in students of high and low ability in reading comprehension. Sixty-four junior high students were divided into four equal-sized groups on the basis of preassessed reading ability (high and low) and preassessed amount of existing prior knowledge about baseball (high and low). Each subject silently read an account of a half inning of a baseball game. After reading, each subject recalled the account nonverbally by moving figures and verbally by retelling the story. After an interpolated task, they summarized the game and sorted passage sentences for idea importance. There was a significant main effect for prior knowledge on all measures. No interactions between prior knowledge and ability were found. These results delineate the powerful effect of prior knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This is the first dedicated review of quantitative studies on Freud's proposition that the poorer the psychological health, the more limited are the benefits from treatment. Since observer-rated scales for PHS were developed in 1949, many studies have applied them, and the majority show significant prediction of outcomes of psychotherapy, with correlations between .2 and .35. This article reviews (1) the main methods of measurement, (2) the record of predictive success, (3) validity studies, (4) the relation to psychiatric diagnosis, (5) prediction in forms of treatment other than psychotherapy, and (6) theories of why psychological health predicts outcomes of psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
115.
The interaction of organic micropollutants with dissolved organic carbon (DOC) can influence their transport, degradation and bioavailability. While this has been well established for natural organic carbon, very little is known regarding the influence of DOC on the fate of micropollutants during wastewater treatment and water recycling. Dissolved organic carbon-water partition coefficients (KDOC) for wastewater derived and reference DOC were measured for a range of micropollutants using a depletion method with polydimethylsiloxane disks. For micropollutants with an octanol-water partition coefficient (log KOW) greater than 4 there was a significant difference in KDOC between reference and wastewater derived DOC, with partitioning to wastewater derived DOC over 1000 times lower for the most hydrophobic micropollutants. The interaction of nonylphenol with wastewater derived DOC from different stages of a wastewater and advanced water treatment train was studied, but little difference in KDOC was observed. Organic carbon characterisation revealed that reference and wastewater derived DOC had very different properties due to their different origins. Consequently, the reduced sorption capacity of wastewater derived DOC may be related to their microbial origin which led to reduced aromaticity and lower molecular weight. This study suggests that for hydrophobic micropollutants (log KOW > 4) a higher concentration of freely dissolved and thus bioavailable micropollutants is expected in the presence of wastewater derived DOC than predicted using KDOC values quantified using reference DOC. The implication is that naturally derived DOC may not be an appropriate surrogate for wastewater derived DOC as a matrix for assessing the fate of micropollutants in engineered systems.  相似文献   
116.
To define the capacity to organize verbal learning after frontal lobe injury, 32 patients with stable frontal lesions were evaluated with list learning tasks. Lesion size and site were determined from CAT or magnetic resonance imaging (MRI) scans. The lists were contructed to assess several potential organizational processes. A mild deficit in recognition performance was observed in patients with left frontal lesions accompanied by residual minor language impairments or in patients with septal lesions. Patients with frontal lesions also had a verbal recall deficit that was related to several factors: poor higher order organization of learning, independent of lesion size or site; a selective secondary memory impairment, associated with a language deficit and size of the lesion in the left frontal region; and excess intralist repetitions in patients with right frontal lesions. Impaired list learning after frontal lesions involves several independent psychological processes. This functional heterogeneity is based on regional anatomical specialization and dissociation of task processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
117.
Subsurface Characterization at Ground Failure Sites in Adapazari, Turkey   总被引:4,自引:0,他引:4  
Ground failure in Adapazari, Turkey during the 1999 Kocaeli earthquake was severe. Hundreds of structures settled, slid, tilted, and collapsed due in part to liquefaction and ground softening. Ground failure was more severe adjacent to and under buildings. The soils that led to severe building damage were generally low plasticity silts. In this paper, the results of a comprehensive investigation of the soils of Adapazari, which included cone penetration test (CPT) profiles followed by borings with standard penetration tests (SPTs) and soil index tests, are presented. The effects of subsurface conditions on the occurrence of ground failure and its resulting effect on building performance are explored through representative case histories. CPT- and SPT-based liquefaction triggering procedures adequately identified soils that liquefied if the clay-size criterion of the Chinese criteria was disregarded. The CPT was able to identify thin seams of loose liquefiable silt, and the SPT (with retrieved samples) allowed for reliable evaluation of the liquefaction susceptibility of fine-grained soils. A well-documented database of in situ and index testing is now available for incorporating in future CPT- and SPT-based liquefaction triggering correlations.  相似文献   
118.
In this study, 361 adult burn survivors completed the Perceived Stigmatization Questionnaire (PSQ), the Social Comfort Questionnaire (SCQ), and other measures. Both the PSQ and SCQ had good internal consistency indices. Factor analysis of the PSQ yielded 3 factors (absence of friendly behavior, confused/staring behavior, and hostile behavior). The SCQ had 1 factor. Conjoint factor analysis with measures of related constructs (body esteem, body-esteem importance, depression, social support) suggested that PSQ and SCQ measure distinct constructs. Correlations with the related psychosocial constructs and burn characteristics suggested the PSQ and SCQ have good convergent and discriminant validity. Limitations of the study are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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120.
The chemical tracking of sewage effluents discharged into fresh and saline waters presents difficulties, especially in estuaries. The main difficulty is caused by the dissolved constituents being used to monitor the effluent also occurring naturally at similar levels. Uric acid is present at significant levels in untreated sewage and is not normally found in unpolluted waters. Until now no suitable routine method has been available for uric acid estimation in fresh and saline waters at levels normally encountered in the environment. In this paper we describe a recently developed technique using high-performance liquid chromatography which estimates uric acid in both fresh and saline waters in the range 1–10,000 μg l−1 with a precision (2σ) of ±20% at 2 μg l−1, ±4% at 40 μg l−1 and ±2% at 10 mg l−1.  相似文献   
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