Fiber optic biosensor of immobilized firefly luciferase

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.     

Introduction to this Special Issue

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.     

Kinetics study on biomass pyrolysis for fuel gas production

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     

普通话二字组词语的动态声调

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     

Teaching Undergraduate Mathematics on the Internet

This is Part 2 of a two-part study of how APOS theory may be used to provide cognitive explanations of how students and mathematicians might think about the concept of infinity. We discuss infinite processes, describe how the mental mechanisms of interiorization and encapsulation can be used to conceive of an infinite process as a completed totality, explain the relationship between infinite processes and the objects that may result from them, and apply our analyses to certain mathematical issues related to infinity.