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1.
2.
Comments on the D. Lachar et al (see record 1984-19420-001) evidence of external validity for Personality Inventory for Children (PIC), which is based on correlations of PIC scales with dimension scores derived from factor analyses of behavioral ratings. It is argued that due to considerable item overlap between PIC scales and behavior rating forms, correlations may be an indication of rater reliability rather than one of construct validity. This problem is thought to be especially evident for rating forms completed by parents because parents also completed the PIC, and many items are similar in both content and wording. The problem is illustrated using the hostility/dyscontrol dimension derived from parent ratings. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
An ordering of magnesium is observed in the as-synthesized MAPO-36 molecular sieve. Upon calcination, part of the magnesium is removed from the sample and part occupies extraframework positions thus rendering a random distribution of magnesium in the lattice. The shoulder observed in the31P spectrum of the calcined sample is assigned to P(3Al, 1Mg) sites in conflict with the earlier assignment to P-OH groups. The bridging hydroxyl groups located at these sites are detected in the1H MAS spectrum at 3.6 ppm. Further, MAPO-36 catalyzed acetone conversion to mesityloxide that cracked at elevated temperature to yield acetic acid and aliphatics. 相似文献
4.
Bendriem B Dewey SL Schlyer DJ Wolf AP Volkow ND 《IEEE transactions on medical imaging》1991,10(2):216-222
The accurate measurement of the concentration of a radioisotope in small structures with positron emission tomography (PET) requires a correction for quantitation loss due to the partial volume effect and the effect of scattered radiation. To evaluate errors associated with measures in the human basal ganglia (BG), a unilateral model of the BG has been inserted in a 20-cm cylinder. The recovery coefficient (RC=measured activity/true activity) for the BG phantom has been measured on a CTI tomograph with different background concentrations (contrast) and at different axial locations in the gantry. The BG was visualized on four or five slices, depending on its position in the gantry and on the contrast used. The RC was 0.75 with no background (contrast equal to 1.0). Increasing the relative radioactivity concentration in the background increased the RC from 0.75 to 2.00 when the contrast was -0.7 (BG相似文献
5.
N. Kalra T. Lauwers D. Dewey T. Stepleton M. B. Dias 《Information Systems Frontiers》2009,11(2):117-128
Less than 3% of the 145 million blind people living in developing countries are literate (Helander, Prejudice and dignity: An introduction to community-based rehabilitation. New York: UNDP 1998). This low literacy rate is partly due to the lack of trained teachers and the challenges associated with learning to write
braille on a traditional slate and stylus. These challenges include writing from right to left, writing mirrored images of
letters, and receiving significantly delayed feedback. Extensive conversations with the Mathru Educational Trust for the Blind
near Bangalore, India, revealed the need for a robust, low-power, low-cost braille writing tutor. We present an iterative
and participatory process resulting in the creation and refinement of a prototype braille writing tutor system. This system
uses a novel input device to capture a student’s activity on a slate using a stylus and uses a range of techniques to teach
braille writing skills to both beginner and advanced students. We report on lessons learned from the implementation of this
project and from a 6-week pilot study at Mathru, and outline future directions for improvement.
相似文献
T. LauwersEmail: |
6.
Dr. Ying‐Ying Huang Dr. Thiagarajan Balasubramanian Dr. Eunkyung Yang Dr. Dianzhong Luo Dr. James R. Diers Prof. David F. Bocian Prof. Jonathan S. Lindsey Prof. Dewey Holten Dr. Michael R. Hamblin 《ChemMedChem》2012,7(12):2155-2167
A series of four stable synthetic bacteriochlorins was tested in vitro in HeLa cells for their potential in photodynamic therapy (PDT). The parent bacteriochlorin (BC), dicyano derivative (NC)2BC and corresponding zinc chelate (NC)2BC–Zn and palladium chelate (NC)2BC–Pd were studied. Direct dilution of a solution of bacteriochlorin in an organic solvent (N,N‐dimethylacetamide) into serum‐containing medium was compared with the dilution of bacteriochlorin in Cremophor EL (CrEL; polyoxyethylene glycerol triricinoleate) micelles into the same medium. CrEL generally reduced aggregation (as indicated by absorption and fluorescence) and increased activity up to tenfold (depending on bacteriochlorin), although it decreased cellular uptake. The order of PDT activity against HeLa human cancer cells after 24 h incubation and illumination with 10 J cm?2 of near‐infrared (NIR) light is (NC)2BC–Pd (LD50=25 nM ) > (NC)2BC > (NC)2BC–Zn ≈ BC. Subcellular localization was determined to be in the endoplasmic reticulum, mitochondria and lysosomes, depending on the bacteriochlorin. (NC)2BC–Pd showed PDT‐mediated damage to mitochondria and lysosomes, and the greatest production of hydroxyl radicals as determined using a hydroxyphenylfluorescein probe. The incorporation of cyano substituents provides an excellent motif for the enhancement of the photoactivity and photostability of bacteriochlorins as PDT photosensitizers. 相似文献
7.
Leonid Churilov Audur Fridriksdottir Mahsa Keshtkaran Ian Mosley Andrew Flitman Helen M. Dewey 《Computers & Operations Research》2013
Stroke is the third most common cause of death and the sixth most common cause of disability worldwide. Treating acute ischemic stroke with thrombolytic therapy within 4.5 hours from symptom onset is effective in improving patient outcomes. The time from stroke onset to arrival to hospital has been identified as the single most important issue in determining patients' eligibility for stroke thrombolysis. There is a need for simultaneous systemic evaluation of multi-factorial interventions in pre-hospital acute care systems, aimed at increasing patients' eligibility for stroke thrombolysis. In this paper an OR solution is proposed in the form of a simulation model that provides clear measure of the relative benefit of alternative potential interventions, demonstrating how OR modeling can be used for providing decision support in pre-hospital stroke care operations and contributing to health OR literature. 相似文献
8.
Nonholonomic constraint equations that are nonlinear in velocities are incorporated with Kane's dynamical equations by utilizing
the acceleration form of constraints, resulting in Kane's nonminimal equations of motion, i.e. the equations that involve
the full set of generalized accelerations. Together with the kinematical differential equations, these equations form a state-space
model that is full-order, separated in the derivatives of the states, and involves no Lagrange multipliers. The method is
illustrated by using it to obtain nonminimal equations of motion for the classical Appell–Hamel problem when the constraints
are modeled as nonlinear in the velocities. It is shown that this fictitious nonlinearity has a predominant effect on the
numerical stability of the dynamical equations, and hence it is possible to use it for improving the accuracy of simulations.
Another issue is the dynamics of constraint violations caused by integration errors due to enforcing a differentiated form
of the constraint equations. To solve this problem, the acceleration form of the constraint equations is augmented with constraint
stabilization terms before using it with the dynamical equations. The procedure is illustrated by stabilizing the constraint
equations for a holonomically constrained particle in the gravitational field. 相似文献
9.
Kimmons JE Dewey KG Haque E Chakraborty J Osendarp SJ Brown KH 《Food and nutrition bulletin》2004,25(3):228-238
This study used simple rapid-assessment techniques to test the feasibility of increasing the consumption of complementary foods by infants by asking mothers to increase meal quantity or frequency or by altering the viscosity/energy density of the food. The feasibility of using micronutrient supplements either added directly to food or administered as liquid drops was also examined. The study was conducted in rural Bangladesh and involved four separate short-term behavioral change trials. Depending on the trial, fieldworkers recruited 30 to 45 infants 6 to 12 months of age. Following recommendations to increase the amount of food provided to infants, the mean intakes from single meals increased from 40 +/- 23 g on day 1 to 64 +/- 30 g on day 7 (p < 0.05). In a second trial, the mean meal frequency increased from 2.2 +/- 1.3 on day 1 to 4.1 +/- 1.3 on day 7 (p < 0.05). Provision of high-energy-density diets, prepared by decreasing viscosity with alpha-amylase or by hand-mashing rice and dhal into a paste before feeding, increased single-meal energy consumption from 54 +/- 35 kcal to 79 +/- 52 kcal or 75 +/- 37 kcal (p < 0.05), respectively. Both types of micronutrient supplements were well accepted and used according to recommendations. In conclusion, it was possible to change short-term child-feeding behaviors to promote increased food intake, mealfrequency, energy density, and micronutrient consumption. Because each of these interventions lasted for only about 1 week, however, the long-term sustainability of these changes is not known. Moreover, the effect of increased feeding of complementary foods on intakes of breastmilk and total daily consumption of energy and nutrients requires further study. 相似文献
10.