The temperature dependence of the electron mobility in ZnMgO/ZnO heterostructures in the Bloch–Grüneisen regime is studied and many-body effects are taken into account. For sufficiently low temperatures, the mobility limited by acoustic scattering follows a stronger, µ∼T-α (α=8.5 for the deformation-potential scattering, α=6.5 for the piezoelectric scattering), temperature dependence, which is significantly different from the traditional µ∼T-1 law. Many-body effects play an important role in the electron transport. The theoretical calculations are able to explain recently published experimental data.

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Executive SummaryE-Rate is a U.S. federal funding program for providing discounts for telecommunications, Internet access and internal networking costs for schools and libraries to ensure access equity across poor and rich, rural, urban and suburban areas, and highly served and underserved areas. This paper examines the impact of the E-Rate program on social equity and educational efficacy in American public schools, based upon the federal government's original purpose for investment. The investigation of these issues was based on a document analysis and interviews. As far as equity is concerned, E-Rate brought about a great improvement in providing access to information technology. However, mere access is not enough for resolving the digital divide in schools. Intrinsic problems of E-Rate, such as complex application process and inflexibility of the usage, result in disproportionate funding nationwide that actually increases the digital divide during the beginning of the program. Continuing disparities between schools regarding the quality as well as the number of connections remain. Thus, the conclusion is that E-Rate has yet to accomplish its goals in terms of closing the digital divide between rich and poor schools, rural and urban schools, and even high schools and elementary schools. As far as the effective incorporation of information technology into better teaching and learning is concerned, the study suggests that ERate can not bring efficacy to the education sector except for providing less than seamless Internet connection to schools. Connection is not necessarily related to productive technology education. Therefore, the telecom sector should align its universal service goals with the vision of the education sector and other funding agencies at private, federal, state and local levels to ensure that technology investments in schools have effective utilization.

Eds.) (2004). The psychology of gender (2nd ed.). New York: The Guilford Press. $48.00. 358 pp. Hardback.At the split second when the tiny sperm and germ meet and merge against all odds, not just the sex of the new human being is established, but many other important aspects in his or her entire later life are predetermined to a certain degree Á/ what clothes should/not be worn, what words should/not be said, what behaviors should/ not be preformed, what responsibility should be taken as obligatory, etc. Among the genres of research that try to untangle the mystery, a psychological perspective is a more convictive one in that it goes deeply to the root of all the problems Á/ the human mind, where the whole non-natural world has originated from. To answer what gender differences and similarities are, and to explain why, how and when gender has an impact on life, three researchers made their contributions by compiling a systematic collection of theoretical explanations in their co-edited book The Psychology of Gender. Overview of Contents Biological ProcessesIn chapter two, the authors argue that prenatal environment and exposure to estrogen and androgen can not only influence human brain development, but also childhood play behavior, core gender identity, personality, sexual orientation, cognition and language lateralization, and hand preferences. Chapter three reviews the activational effects of reproductive hormones on cognition including perceptions, thoughts, moods, and characteristics, comparing the different effects between men and women. Hormones are not the only things that can explain gender differences.

Driven by social, economic, academic and technological forces, the new field of E-health has been developing quickly in recent years. Many E-health applications are Internet-based and therefore have the potential to help people throughout the world. However, this high dependence on the Internet also raises sobering questions about a health digital divide, i.e. unequal access and use as well as unequal rights to gain benefits of online information among health consumers. In this paper, we discuss social, cultural and economic factors which shape a research agenda for examining health digital divide issues.