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71.
72.
Luciferase from firefly lantern extract was immobilized on CNBr-activated Sepharose 4B. The kinetic properties of immobilized luciferase were extensively studied. TheK m′ for D-luciferin is 11.9 μmol/L, the optimum pH and temperature for Sepharose-bound enzyme were 7.8 and 25°C respectively. A luminescence fiber optic biosensor, making use of immobilized crude luciferase, was developed for assay of ATP. The peak light intensity was linear with respect to ATP concentration in range of 10−9–10−5 mol/L. A biological application was also demonstrated with the determination of serum ATP from rats bred in low versus normal oxygen environments.  相似文献   
73.
74.
In 2001, for the first time in the history of the International Association for Counselling, International Conference was held in a developing Asian country–India, with the theme Families in Transition–Counselling in Transition–Meeting the Challenges Ahead. This special issue contains some of the presentations made by Indian participants during this conference which best reflect the challenges and diversities of counseling efforts with families in India. The first article was specially written for this issue in order to give an international relationship of this journal an in depth contextual understanding of Indian families in transition and the challenges they pose to the contemporary Indian counselor. Two articles are reflected to counseling families affected by socio-politial and economic changes. Five authors have written on counseling related to physical and mental disability/addiction and last two articles are reflected to authors experiences as family counselors.  相似文献   
75.
Kinetic knowledge is of great importance in achieving good control of the pyrolysis and gasification process and optimising system design. An overall kinetic pyrolysis scheme is therefore addressed here. The kinetic modelling incorporates the following basic steps: the degradation of the virgin biomass materials into primary products (tar, gas and semi-char), the decomposition of primary tar into secondary products and the continuous interaction between primary gas and char. The last step is disregarded completely by models in the literature. Analysis and comparison of predicted results from different kinetic schemes and experimental data on our fixed bed pyrolyser yielded very positive evidence to support our kinetic scheme. Project (No. 2001CB409600) Supported by the National Key Basic Research Program (973) of China  相似文献   
76.
The author asserts that the field of teacher education must begin a critical conversation to better prepare and support teachers in attending to the complexities of racialized identities, experiences, and perspectives of multiracial students in K12 schools. The author offers a review of literature relevant to multiracial students, and draws from the emerging theoretical framework of Multicrit (Harris in Int J Qual Stud Educ 29(6):795–813, 2016) to present monoracism, ahistoricism, colorism and intersectionality to analyze excerpts from three respective research studies. Each excerpt demonstrates an imperative to build a critical understanding of multiracial students within teacher work. The author concludes with implications for future research and practice.  相似文献   
77.
The purpose of this study was to examine undergraduate and graduate student enrollments, course delivery modes, and curricular trends and issues of CTE programs. Based on findings from 139 program/department coordinators, results emphasized that although CTE programs within institutions of higher education have declined in number (Fletcher, Gordon, Asunda, &; Zirkle, 2015 Fletcher, E., &; Djajalaksana, Y. (2015). Instructional strategy preferences in the career and technical education classroom. Journal of Research in Business Education, 57(1), 3256. [Google Scholar]), student enrollments within those programs have remained steady compared to prior studies (Bruening et al., 2001 Bruening, T., Scanlon, D., Hodes, C., Dhital, P., Shao, X., &; Liu, S. (2001). The status of career and technical education teacher preparation programs. (Report No. V051A990004). Minneapolis, MN: The National Research Center for Career and Technical Education. [Google Scholar]; Lynch, 1990 Lynch, R. (1990). A national database on vocational teacher education (Report No. V051A80004-89). Berkeley, CA: National Center for Research in Vocational Education. [Google Scholar]). Even so, CTE program/department administrators have articulated that declining student enrollment is a major challenge within their programs. Additionally, the development of online courses and the impact of state/national educational reform initiatives were identified as major curricular trends for CTE programs. Recommendations include the need for CTE faculty to embrace online instruction, and for programs to use broader nomenclature of CTE/Workforce Education, instead of names of more traditional subdisciplines within the field to remain more accessible and sustainable in the future. The condition of undergraduate and graduate CTE programs will likely impact the viability and sustainability of CTE teacher preparation programs, recruitment of a talented and diverse CTE teaching force, continuity of the U.S. teaching workforce, and ability of K–12 teachers to maintain high-quality CTE programs.  相似文献   
78.
普通话二字组词语不同的声调组合方式 ,使前后位声调产生不同的动态变化形式。前位声调的动态变化明显表现在上声调变为低降调和中升调上 ;后位声调的动态变化则表现在调值的明显改变上。后位声调的动态变化更为普遍 ,应该引起足够的重视  相似文献   
79.
Both cross sectional and longitudinal studies of change with age in mental ability and cross sectional studies of change with age in cognitive performance indicate that the ability to learn generally does not decline in adulthood but continues at a stable and responsive level well into the later years. This conclusion is not only supported by psychological research but also confirmed by the rapidly growing numbers of older persons who are returning to and succeeding in the pursuit of educational activities. If and when decline does occur, it is usually modest, often reversible, rarely extreme, and rarely if ever great enough to preclude the possibility of learning that may be highly meaningful to the older learner.Howard Y. McClusky is the charter President of the Adult Education Association of the U.S.A. and a Fellow of the American Psychological Association. He is currently active as an Adjunct Professor in the Department of Adult and Continuing Education and Faculty Associate in the Institute of Gerontology at the University of Michigan, Ann Arbor, Michigan 48109.  相似文献   
80.
Asymmetries in the progression of unilaterally and bilaterally induced audiogenic seizures were examined in DBA/2J and SJL/J mice. Both strains were found to exhibit consistent asymmetries in direction(s) of running as well as in the side of fall during a convulsion. This correspondence suggests that the bursts of running are an integral part of an audiogenic seizure. The incorporation of information on asymmetries of the locomotor prelude in future studies should prove valuable for understanding the physiological mechanisms of audiogenic seizure.  相似文献   
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