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71.
National, state, and local education reform agendas have been on a fast track for more than a decade. Although some psychologists have been active in promoting psychology and psychological services in education reform initiatives, knowledge about their efforts is fragmented. In order to educate psychologists about education reform, this article highlights the impetus for the recent education reform movement, briefly reviews the latest waves of education reform, and discusses the development of the National Education Goals. Then, an argument is made for the integration of education, health, and social reform initiatives; state-level education reform principles and initiatives are highlighted, illustrated by the systemic education reform mandate in Kentucky. Next, progress toward the development and implementation of an APA-sponsored response to the National Education Goals is discussed. Finally, objectives and roles for psychologists in advancing education reform are presented, and guidelines for the education and training of future psychologists are introduced. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
Expansion and shrinkage tests on mortars made from a range of cements with SO3 contents in excess of the limits specified in BS 12 are described. The mortar specimens were cured under water from 24 hours to 7 days and then dried at 65% RH and 20°C. It is shown that there is a small range of SO3 contents within which sharp increases in 7 day expansion occur ranging from 80 to 170 micro-strain/SO3% and that within this small range of SO3 contents the subsequent drying shrinkage is not adversely affected.  相似文献   
73.
A review of the literature demonstrates that production deficiency hypotheses are unable to account fully for the fact that older adults perform more poorly on memory tasks than young adults. The possibility is explored that age-related differences are due to changes in fundamental processes involved in retrieval of information from memory, namely, (a) utilization of contextual information and (b) activation processes occurring in semantic memory. Automatic as well as intentional processes are examined. (5? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Using both Rayleigh scattering and time-resolved emission spectroscopy, we have recorded the spatial and temporal evolution of laser-generated sparks in argon from changes during the first ten of nano-seconds to complete dissipation, which occurs in a time span of approximately 5 ms. Maps of either emission intensity or argon density spanning the entire region affected by the energy deposited by the laser show the dissipation of the spark in detail. Immediately after ignition, the argon plasma occupies an ellipsoidal volume of roughly 3-mm vertical (axial) length. After approximately 20-40 micros, the spark region has transformed into a toroidal shape in a plane perpendicular to the vertical axis, with a radius of approximately 1.5 mm. The torus rises slowly up and expands noticeably in the radial direction. A record of peak temperatures of the spark ranging from approximately 10,000 K at 60-micros delay time to approximately 450 K at 4-ms delay time indicate cooling rates from approximately 100 to 1 K/micros at these times.  相似文献   
75.
A data anomaly was observed that affected the uniformity and reproducibility of fluorescent signal across DNA microarrays. Results from experimental sets designed to identify potential causes (from microarray production to array scanning) indicated that the anomaly was linked to a batch process; further work allowed us to localize the effect to the posthybridization array stringency washes. Ozone levels were monitored and highly correlated with the batch effect. Controlled exposures of microarrays to ozone confirmed this factor as the root cause, and we present data that show susceptibility of a class of cyanine dyes (e.g., Cy5, Alexa 647) to ozone levels as low as 5-10 ppb for periods as short as 10-30 s. Other cyanine dyes (e.g., Cy3, Alexa 555) were not significantly affected until higher ozone levels (> 100 ppb). To address this environmental effect, laboratory ozone levels should be kept below 2 ppb (e.g., with filters in HVAC) to achieve high quality microarray data.  相似文献   
76.
77.
A novel processing procedure for significantly suppressing grain growth in submicrometer alumina compacts has been developed and implemented with the intent of ultimately using the same processing route to control grain size in nanophase alumina compacts. In this study, partially sintered alumina pellets made from 0.5 µm starting powders are altered by the chemical infiltration of Si3N4. The control and infiltrated pellets are then heated to 1650°C for 4 h. The fully sintered pellets are approximately 97% dense. Suppressed grain growth is observed in the infiltrated pellets. The average grain size in the control pellets after densification is 4.2 and 1.2 µm in the infiltrated pellets. Depth of infiltration is measured using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Depending on the specific infiltration conditions used, the outer 15-50% of the infiltrated pellets exhibit a graded microstructure consisting of a region of abnormal grain growth and a region of suppressed grain growth. Abnormal grain growth is visible on the outer surfaces of the infiltrated pellets where a relatively high ratio of Si to N is present. Further into the pellet, after some depletion of the Si source gas has occurred, regions of suppressed grain growth are apparent. Based on these results, an infiltration profile is determined. A mathematical model is developed to describe the infiltration process and to determine optimal infiltration conditions. High-resolution electron microscopy (HREM), energy dispersive spectroscopy (EDS), electron energy loss spectroscopy (EELS), and X-ray photoelectron spectroscopy (XPS) are used to study the infiltrated samples.  相似文献   
78.
High speed power     
This paper presents the need for compatibility between European rail networks. This leads to the adoption of dual 25 kV as the power of choice for operators. Dual 25 kV literally doubles the power available to rail networks, helping rail operators to meet some of the demands they are facing. Not surprisingly, this fact, along with the EU directive on 'interoperability of the trans-European high speed rail system', which aims to ease the circulation of high-speed trains through the various train networks of the European Union, will lead it to become the future standard across Europe  相似文献   
79.
This longitudinal study used multilevel modeling to examine the relationships between witnessing intimate partner violence (IPV), community and school violence exposure (CSVE), family social support, gender, and depression over 2 years within a sample of 100 school-aged children. We found significant between-child differences in both the initial levels of depression and the trajectories of depression; depression over time was positively associated with change in witnessing IPV and CSVE and negatively associated with change in support. Two significant 3-way interactions were found: Gender and initial support, as well as gender and initial witnessing IPV, both significantly moderated the effect of change in witnessing IPV on the children’s depression over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.

Objective

Among other neuroimaging techniques, functional magnetic resonance imaging (fMRI) can be useful for studying the development of motor fatigue. The aim of this study was to identify differences in cortical neuronal activation in nine subjects on three motor tasks: right-hand movement with minimum, maximum, and post-fatigue maximum finger flexion.

Materials and methods

fMRI activation maps for each subject and during each condition were obtained by estimating the optimal model of the hemodynamic response function (HRF) out of four standard HRF models and an individual-based HRF model (ibHRF).

Results

ibHRF was selected as the optimal model in six out of nine subjects for minimum movement, in five out of nine for maximum movement, and in eight out of nine for post-fatigue maximum movement. As compared to maximum movement, a large reduction in the total number of active voxels (primary sensorimotor area, supplementary motor area and cerebellum) was observed in post-fatigue maximum movement.

Conclusion

This is the first approach to the evaluation of long-lasting contraction effort in healthy subjects by means of the fMRI paradigm with the use of an individual-based hemodynamic response. The results may be relevant for defining a baseline in future studies on central fatigue in patients with neuropathological disorders.  相似文献   
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