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101.
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Arda Gen Rajarshi Banerjee Gregory B. Thompson Dennis M. Maher Andrew W. Johnson Hamish L. Fraser 《Ultramicroscopy》2009,109(10):1276-1281
An aberration corrector on the probe-forming lens of a scanning TEM (STEM) equipped with an electron energy-loss spectrometer (EELS) and X-ray energy-dispersive spectrometer (XEDS) has been employed to investigate the compositional variations as a function of length scale in nanoscale Ti/Nb metallic multilayers. The composition profiles of EELS and XEDS were compared with the profiles obtained from the complementary technique of 3D atom probe tomography. At large layer widths (h≥7 nm, where h is the layer width) of Ti and Nb, XEDS composition profiles of Ti/Nb metallic multilayers are in good agreement with the EELS results. However, at reduced layer widths (h≈2 nm), profiles of EELS and atom probe exhibited similar compositional variations, whereas XEDS results have shown a marked difference. This difference in the composition profiling of the layers has been addressed with reference to the effects of beam broadening and the origin of the signals collected in these techniques. The advantage of using EELS over XEDS for these nanoscaled multilayered materials is demonstrated. 相似文献
103.
Reviews the book, MMPI-168 codebook by Ken R. Vincent et al (1984). This book is an effort to present an actuarially devised system for use with the MMPI-168, a widely researched short form of the MMPI. It is an effort to move the MMPI-168 out of the category of screening instrument and into the area of a significant assessment instrument. The authors emphasize that the value in using the MMPI-168 and its complementary actuarial system will be its utility with patients having poor motivation, illiteracy, or physical disabilities. Psychologists using the MMPI-168 must be aware of several basic concerns, particularly those involved in research. For example, it is a different test from the MMPI, involving only the first 168 items, and it is normed on a nonrandomized sample of private psychiatric clinic patients. In examining the utility of brief assessment instruments, it would be of value to compare the utility of the MMPI-168 or other "short forms" to a validated structured interview procedure. There is no doubt that these types of assessment tools are needed in the field of rehabilitation psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
The most important factor in shoreline wetlands is variation in water depth. Superimposed upon this are gradients of soil fertility, ranging from sandy, open shorelines to sheltered, fertile bays. The use of both transplant and pot experiments shows that competitive hierarchies rapidly arise in wetland vegetation and that species are sorted along exposure and depth gradients according to their relative competitive abilities. These patterns can be summarized in the centrifugal organization model, in which competitive dominants occupy preferred core habitats and where different species and vegetation types are then arrayed outward along different constraint gradients ( Wisheu & Keddy 1992 ). Knowledge of these general patterns provides an essential tool for managing lakes and reservoirs in order to maintain and enhance biological diversity. 相似文献
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Diarrhea is still a major cause of morbidity and mortality among children in developing countries. The Bedouin population of southern Israel is in transition from a nomadic to a settled life-style. We examined maternal knowledge and reported behavior when their children had diarrhea. Mothers defined diarrhea as the passing of 4-5 stools per day. The most frequent signs of the illness were an increased number of watery stools with changes in either color or form. The most frequent symptom that prompted mothers to seek medical aid was blood in the stool. All mothers reported increasing fluid intake in their children during diarrhea, and most reported giving herbal tea. About half of the women avoided milk products and used special foods for the treatment of diarrhea. A quarter of the women reported stopping or decreasing the frequency of breast feeding during diarrhea. Reported cessation of breast feeding during diarrhea was associated with changing to special foods, and failure to note the onset of diarrhea or to recognize signs of dehydration. The withdrawal of breast feeding during episodes of illness and diarrhea is related to lack of knowledge regarding diarrhea. These data indicate that even in this population, with free access to preventive and curative medical care, there should be greater efforts to educate mothers to detect diarrheal disease and to maintain breast feeding during the diarrhea. 相似文献
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The effect of variations in composition on optical properties was studied. The index of refraction is lowered by the substitution of fluorine and alumina for silica; the reciprocal dispersion, however, is increased by fluorine and lowered by alumina so that fluorine and alumina can be balanced against each other to give almost any desired optical properties within the field investigated, that is, in the range of 1.46 to 1.50 for index of refraction and 63 to 70 for the reciprocal dispersion. 相似文献
110.
N. de Cediel C. G. Fraser A. Deom L. Josefsson H. G. J. Worth O. Zinder 《Journal of Automated Methods and Management in Chemistry》1989,11(3):99-105
Trainees in laboratory medicine must develop skills in laboratory
management. Guidelines are detailed for laboratory staff in
training, directors responsible for staff development and professional
bodies wishing to generate material appropriate to their
needs. The syllabus delineates the knowledge base required and
includes laboratory planning and organization, control of operations,
methodology and instrumentation, data management and
statistics, financial management, clinical use of tests, communication,
personnel management and training and research and
development. Methods for achievement of the skills required are
suggested. A bibliography of IFCC publications and other
material is provided to assist in training in laboratory management. 相似文献