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91.
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93.
IPv4, the workhorse protocol of the currently popular TCP/ IP protocol suite, is fast becoming obsolete. The exponential growth
of the Internet is the main reason that has required the creation of the next generation of Internet Protocol-IPv6. IPv6 is
much more flexible and promises to take care of the address space and security issues in the foreseeable future.
Part 1 of the paper lays the foundation of the various issues involved in designing the Internet Protocol and motivates the
need for an upgraded version of this protocol. 相似文献
94.
Campbell AM Zanta CA Heyer LJ Kittinger B Gabric KM Adler L Schulz B 《CBE life sciences education》2006,5(4):332-339
We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula. 相似文献
95.
96.
In many Western science systems, funding structures increasingly stimulate academic research to contribute to practical applications,
but at the same time the rise of bibliometric performance assessments have strengthened the pressure on academics to conduct
excellent basic research that can be published in scholarly literature. We analyze the interplay between these two developments
in a set of three case studies of fields of chemistry in the Netherlands. First, we describe how the conditions under which
academic chemists work have changed since 1975. Second, we investigate whether practical applications have become a source
of credibility for individual researchers. Indeed, this turns out to be the case in catalysis, where connecting with industrial
applications helps in many steps of the credibility cycle. Practical applications yield much less credibility in environmental
chemistry, where application-oriented research agendas help to acquire funding, but not to publish prestigious papers or to
earn peer recognition. In biochemistry practical applications hardly help in gaining credibility, as this field is still strongly
oriented at fundamental questions. The differences between the fields can be explained by the presence or absence of powerful
upstream end-users, who can afford to invest in academic research with promising long term benefits. 相似文献
97.
98.
The experiment was conducted to assess the effect of ordinary school art instruction in human figure drawing on scores of the Goodenough-Harris Drawing Test. Subjects consisted of 44 fifth-grade students attending a suburban parochial school who were members of two preexisting, randomly assigned homeroom classes. Both classes were taught two lessons in art by their regular teachers. The treatment group was taught human figure drawing, and the control group had art lessons excluding figure drawing instruction. The Drawing Test was administered three times, one preinstruction and two postinstruction administrations. Absenteeism reduced treatment and control groups to 14 and 17 subjects, respectively. As predicted, no differences were found in the control group between pretest and postests. The treatment group showed significant gains on both posttests, as well as a significant decline from the first posttest to the second posttest. 相似文献
99.
100.
Aging and its effects on a person's quality of life are a growing health concern and burden for many Americans. Recently, studies have shown that adopting certain healthy behaviors may help maintain and or prevent age-related health issues such as cognitive decline. However, many people are unaware of these newfound facts. Furthermore, there is insufficient research evidence to understand how older adults view brain health and the differences between diverse groups of older adults. This study examines brain health knowledge and behaviors among Caucasian and African-American community-dwelling older adults in North Carolina. Findings were significant for level of education and total brain health knowledge scores, though there were no significant differences between races. In addition, there was a significant association between total number of health conditions and total brain health knowledge scores that warrants further study. 相似文献