Engineering a Web site

The World Wide Web (WWW) is famous for weaving far-flung fans with like interests into true communities. It also puts a spin all its own on product and information delivery. Nowhere is this more apparent than in a global industry such as electrical and electronic engineering. The Web is still unmatched in its ability to receive and distribute information and software, and to encourage interaction and collaboration. These strengths stem from the Web's combination of many of the best features of existing media-audio, video, text, and graphics-to which it adds some unique new talents, such as the ability to manipulate information through software. Most corporations acknowledge the opportunities the Web presents. The paper presents some guidelines on how best to start turning them to advantage     

Mathematical and Scientific Foundations for an Integrative Engineering Curriculum

All fields of engineering, whether chemical, civil, electrical, materials, mechanical, etc., encompass a common body of essential mathematics and science. In the freshman year of Drexels E⁴ program, this common mathematical and scientific foundation is cultivated in the Mathematical and Scientific Foundations of Engineering I, II and III (MSFE I, MSFE II, MSFE III). In an integrated fashion, MSFE I presents the essential calculus, physics and engineering mechanics vital to the freshman engineering student. In the first two quarters, MSFE II presents chemistry with clearly defined engineering applications and significance: in the third quarter, MSFE II presents living systems with the same thrust. Also in the third quarter, MSFE III presents basic circuits and circuit elements, and a brief introduction to electromagnetic theory.     

Zum Einfluß extrazellulärer polymerer Substanzen bei der mikrobiologisch beeinflußten Korrosion

The influence of extra-cellular polymeric substances in microbiologically influenced corrosion Unexpected pitting failures in copper potable water installations have occurred in some countries (Germany, Sweden, Scotland, South-West England, Saudi-Arabia) in the mid-eighties. These failures could not be expected in a single case based on the chemical composition of the potable water. Further typical manifestation characteristics of this microbiologically influenced corrosion have been i.) an uptake of dissolved and undissolved copper species in an obsolete, non regular fashion, ii.) black layers of copper(II)-oxide on the inner tube surface, accompanied by posniakite and malachite in the pitting areas, and, iii.) the detection of extracellular polymeric substances (EPS). These EPS consist partly of polysaccharides. They could either be produced by microorganisms within the potable water installation or be transported in a dissolved or undissolved state into the installation. Consequently, they sediment on the inner surfaces of the copper tubes. The physico-chemical properties of some kinds of EPS, especially their membrane properties and their cation selectivity, play a key role in this corrosion process. This is shown exemplarily performing diffusion potential measurements and contact corrosion experiments.     

Opposite phenotypes of hypomorphic and Y766 phosphorylation site mutations reveal a function for Fgfr1 in anteroposterior patterning of mouse embryos

Intercellular communication is needed for both the generation of the mesodermal germ layer and its division into distinct subpopulations. To dissect the functions of fibroblast growth factor receptor-1 (FGFR1) during mouse gastrulation as well as to gain insights into its possible roles during later embryonic development, we have introduced specific mutations into the Fgfr1 locus by gene targeting. Our results show functional dominance of one of the receptor isoforms and suggest a function for the autophosphorylation of site Y766 in the negative regulation of FGFR1 activity. Y766F and hypomorphic mutations in Fgfr1 generate opposite phenotypes in terms of homeotic vertebral transformations, suggesting a role for FGFR1 in patterning the embryonic anteriorposterior axis by way of regulation of Hox gene activity.     

Using neural networks to select wavelet features for breast cancerdiagnosis

This study focuses on improving microcalcification classification by establishing an efficient computer-aided diagnosis system that extracts Daubechies-4 and biorthogonal wavelet features. These wavelets were chosen because they have been used in military target recognition and fingerprint recognition research with images characterized by low contrast, similar to mammography. Feature selection techniques are employed to further increase classification performance. The artificial neural network feature selection techniques are complemented by a conventional decision boundary-based feature selection method. The results using the wavelet features are compared to more conventional measures of image texture, angular second moment, and Karhunen Loeve coefficients. The use of alternative signal processing to compare wavelet and neural techniques allows for a measure of the problem difficulty. It is concluded that advances and contributions have been made with the introduction of two novel feature extraction methods for breast cancer diagnosis, wavelets and eigenmasses. Additionally, feature selection techniques are demonstrated, compared, and validated, transforming adequate discrimination power into promising classification results     

High-resolution analysis of T-cell receptor beta-chain repertoires using DNA heteroduplex tracking: generally stable, clonal CD8+ expansions in all healthy young adults

Harringtonine (HT), an anticancer drug with high chemotherapeutic efficiency to human chronic granulocytic/myelomonocytic leukemia, has been reported to rapidly induce apoptosis in HL-60 cells in a wide scope/range of dosage by investigators from our lab and others. In the present studies, by using video enhancement contrast (VEC) microscopy, we dynamically analyzed changes in intracellular calcium distribution in a single HL-60 cell over the period from the initiation of apoptosis to the obvious appearance of chromatin condensation. The results from this paper demonstrated the striking distinction of intracellular calcium distribution at different time points after treatment with HT. Before treatment in normal HL-60 cells the highest [Ca2+]i accumulation was observed in the peri-nuclear area and the lowest was observed in the nucleus; after treatment with 1 microg/ml HT for 30 min intracellular calcium diffused all over the cell compartments, while intranuclear calcium increased comparatively and significantly. The phenomenon of intranuclear calcium accumulation was further confirmed by using laser scanning confocal microscopy (LSCM). In addition, co-localization of the highest calcium region with condensed chromatin in apoptotic HL-60 cells was also observed by LSCM. Our results suggest that two sequential alterations of intracellular calcium distribution occurred in apoptotic HL-60 cells induced by HT, i.e. (a) accumulation of calcium in the nucleus and (b) regionalization in a specific nuclear region.