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61.
The purpose of the research was to assess the diagnostic efficiency of the Primary Care Posttraumatic Stress Disorder Screen (PC-PTSD) and the Posttraumatic Stress Disorder Checklist (PCL) as clinical screening tools for active duty soldiers recently returned from a combat deployment. A secondary goal was to examine the item-level characteristics of both the PC-PTSD and the PCL. A validation study conducted with a sample of 352 service members showed that both the PC-PTSD and PCL had good diagnostic efficiency. The overall diagnostic efficiency assessed by the area under the curve (AUC) was virtually the same for both the PC-PTSD and PCL. The most efficient cutoff values for the PC-PTSD were either 2 or 3 "yes" responses with the latter favoring specificity. For the PCL, the most efficient cutoff values were between 30 and 34, mirroring recommended PCL cutoff values from some studies in primary care settings. The examination of item characteristics suggested a 4-item PCL with an AUC virtually identical to that of the full PCL. Item analyses also identified that the most discriminate item in both scales pertained to symptoms of avoidance. Implications and limitations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
This study examined the extent to which undergraduate engineering courses taught using active and collaborative learning methods differ from traditional lecture and discussion courses in their ability to promote the development of students' engineering design, problem‐solving, communication, and group participation skills. Evidence for the study comes from 480 students enrolled in 17 active or collaborative learning courses/sections and six traditional courses/sections at six engineering schools. Results indicate that active or collaborative methods produce both statistically significant and substantially greater gains in student learning than those associated with more traditional instructional methods. These learning advantages remained even when differences in a variety of student pre‐course characteristics were controlled.  相似文献   
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64.
Calculations in nitrogen (N) balance research using15N involve several steps that require care to avoid errors. The objective of this paper is to provide examples of these calculations using established procedures and to present shortened alternative calculations that give the same result. The calculations examined include determination of the amount of N to apply, determination of the atom %15N abundance needed in the labeled fertilizer, preparation of the labeled fertilizer, and calculation of the fertilizer N recovered. Calculations needed in the preparation of the labeled fertilizer using established procedures include the determination of the mean atomic weight of the enriched source from which the labeled fertilizer is prepared. This determination is not needed in the shortened alternative calculations, because the procedure places the calculations on a mole basis rather than a mass basis.  相似文献   
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66.
Metallurgical and Materials Transactions A - It is well known that a balance between the generation of low-angle and high-angle grain boundaries (LABG and HAGB) is achieved in materials undergoing...  相似文献   
67.
Aluminum Content in Foods and Beverages Consumed in the Spanish Diet   总被引:1,自引:0,他引:1  
A reliable and rapid method for determining aluminum content in foods and beverages was developed using electrothermal atomization-atomic absorption spectrometry (ETA-AAS) using previous optimization of the time-temperature program for the graphite furnace. The samples were subjected to acid mineralization with HNO3 and V2O5. The technique used slurries for assay in samples of dairy products. The detection limit was 4.0 pg. The mean recovery obtained ranged from 98.5% to 99.0%. The variation coefficient ranged from 3.2% to 5.2%. The results obtained ranged from 1.362 to 6.610 μg/g in seafood, 0.171 to 29.688 μg/g in vegetables, 19.560 to 70.100 μg/g in olive oil, 0.424 to 6.430 μg/g in dairy products and 25.600 to 58.057 μg/g in stimulant drinks and infusions. This study contributes new data on the Al content of a variety of foods and beverages in Spain and such data are important for composition tables. The higher presence corresponded to seafood, vegetables and dairy products. Their contribution to Al dietary intake were estimated.  相似文献   
68.
Matrix metalloproteinases (MMPs), a sort of important enzymes involved in extracellular matrix metabolism, play critical roles in the process of tissues remodeling, wound healing and metastasis of tumors. Dot blot and in situ hybridization were used in this study to detect the expression and localization of MMP-9, an important proteolytic enzyme implicated in bone resorption in bone tissues. The results showed that the level of MMP-9 mRNA expression in osteoporotic bone tissues was significantly higher than that in normal control group and the cell types that expressed MMP-9 mRNA included mono- and multi-nuclear osteoclasts and some lining cells on the surface of bone matrix. It was suggested that MMP-9 play a key role in the development of bone loss in osteoporosis.  相似文献   
69.
The sesquiterpenes farnesol, caryophyllene oxide, and 2,10-bisaboladien-1-one (patent #9602748) and the monoterpenes citronellol and geraniol were tested for settling inhibition and chronic effects on the aphidMyzus persicae by means of an improved leaf-disk assay. Of these compounds, geraniol, famesol, and the natural bisabolene significantly inhibit settling in choice tests. Furthermore, application of the bisabolene to intactCapsicum annuum leaves did not cause phytotoxicity, but did affect the insects' probing behavior by decreasing the probing activity and the number of intracellular punctures. Both compounds significantly decreased offspring production. Of the compounds tested, the natural product bisabolene could be a promising lead for future development of aphid control agents.  相似文献   
70.
Neural networks are receiving attention as controllers for many industrial applications. Although these networks eliminate the need for mathematical models, they require a lot of training to understand the model of a plant or a process. Issues such as learning speed, stability, and weight convergence remain as areas of research and comparison of many training algorithms. This paper discusses the application of neural networks to control induction machines using direct torque control (DTC). A neural network is used to emulate the state selector of the DTC. The training algorithms used in this paper are the backpropagation, adaptive neuron model, extended Kalman filter, and the parallel recursive prediction error. Computer simulations of the motor and neural-network system using the four approaches are presented and compared. Discussions about the parallel recursive prediction error and the extended Kalman filter algorithms as the most promising training techniques is presented, giving their advantages and disadvantages  相似文献   
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