Non-classical kinematic shocks in suspensions of particles in fluids

Summary The properties of weakly nonlinear kinematic waves in suspensions are investigated under the assumption that the particle concentration deviates only slightly from the value at the inflexion point of the drift flux curve. Special emphasis is placed on the conditions for the existence of an internal dissipative-dispersive shock structure. The resulting shock admissibility criteria are found to be significantly different from those following from standard theories of kinematic waves. Most interesting, the analysis shows that non-classical shocks which emanate rather than absorb characteristics may be admissible under certain conditions.     

Universal Digital Portable Communications: A System Perspective

In our highly mobile society, the provision of voice and data communications to a person away from his/her wireline telephone has become a major communications frontier. The early penetration of this frontier has been based on very limited portable communications approaches, e.g., cordless telephones, mobile radio telephones, and radio paging. Each of these approaches only partially satisfies portable communications needs. This paper describes an approach to providing universal digital portable communications integrated into telephone networks. A system configuration employing time-division multiple-access radio link architecture and frequency reuse is described. Issues affecting radio link transmission rates and radio system coverage are discussed. Characteristics and parameters of a possible system to supplement the wire (or fiber) loop are indicated.     

Genetic vaccination against Coccidioides immitis: comparison of vaccine efficacy of recombinant antigen 2 and antigen 2 cDNA

Previous studies from our laboratory established that C-ASWS, an alkali-soluble, water-soluble extract from cell walls of Coccidioides immitis, protects mice against lethal challenge with this fungus. The C-ASWS extract contains a glycosylated protein, designated antigen 2 (Ag2), and a polysaccharide antigen. We recently cloned Ag2 cDNA and showed that the recombinant fusion protein elicited strong delayed-type hypersensitivity responses in immunized mice. This investigation was undertaken to determine if the recombinant Ag2 protein, expressed as an Ag2-glutathione S-transferase (GST) fusion protein, or Ag2 cDNA would protect mice against lethal challenge with C. immitis. The recombinant Ag2-GST protein protected BALB/c mice against intraperitoneal challenge with 250 arthroconidia, as assessed by a decrease in fungal CFU in tissues. The Ag2-GST-immunized mice did not show, however, an increased survival during a 30-day period postinfection. By contrast, immunization of mice with Ag2 cDNA ligated into the pVR1012 plasmid engendered protection against intraperitoneal challenge with 2,500 arthroconidia and against pulmonary challenge with 50 arthroconidia. Vaccine efficacy paralleled the development of delayed-type hypersensitivity responses to C. immitis antigen. Whereas mice vaccinated with the recombinant Ag2-GST protein did not mount footpad hypersensitivity to C-ASWS or the recombinant Ag2-GST protein, mice vaccinated with the pVR1012-Ag2 construct mounted a strong footpad hypersensitivity and their spleen cells secreted gamma interferon upon in vitro stimulation with the Ag2-containing C-ASWS extract. This is the first investigation to show that genetic immunization can protect against lethal challenge with C. immitis.     

Disaster relief work: nurses and others in bushfire territory

This paper describes one aspect of a study into the experiences in long-term healing of a community following the 1983 Ash Wednesday bushfire. Forty participants were interviewed, of whom 26 were residents and 14 disaster relief workers. The paper concentrates on the experiences of the latter, describing how they came to understand the bushfire affected the community and how they managed disaster work. For novices it was a profoundly difficult experience, for which they received little help and had to manage with whatever skill they drew on in their 'normal' working lives, mixed with a good deal of intuition. The paper suggests that health workers in vulnerable areas require preparation for a likely disaster; that 'outsiders' need to deal through existing community groups and individuals to gain access to those in need of their skills, and that they also require preparation for helping 'insiders' who are themselves victims of the catastrophe.     

Mood changes associated with blood glucose fluctuations in insulin-dependent diabetes mellitus.

Examined relationships between blood glucose (BG) levels and self-reported mood in 34 19–68 yr old insulin-independent diabetes mellitus patients. Four times each day, Ss completed a mood/symptom checklist before a self-measurement of BG until 40 checklists had been completed. Half the items of the checklist described physical symptoms, and half described mood states. Within-S correlations and regressions showed that moods were related to BG for the majority of Ss and that, like physical symptoms, mood–BG relationships were idiosyncratic. Low BG levels were associated with negative mood states; positive mood items were almost always associated with high BG. High BG levels also frequently correlated with negative mood states, although the negative mood items that related to high glucose (anger, sadness) differed from those that tended to relate to low BG. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessing Pedagogy in Bioengineering Classrooms: Quantifying Elements of the “How People Learn” Model Using the VaNTH Observation System (VOS)

One goal of the VaNTH Engineering Research Center is to estimate the effects of the “value added” to bioengineering student learning as a result of “How People Learn” (HPL) framework interventions. A necessary step in that process is to assess pedagogical differences in both lecture‐based and HPL‐oriented courses. Data from 28 bioengineering courses, over five semesters, were analyzed using a newly developed HPL Index. This index, developed from the Classroom Interaction Observation portion of the VaNTH Observation System, reports levels of HPL‐inspired pedagogy, traditional pedagogy, and classroom organization within a class using codes for different types of faculty and student interactions assigned by an observer in real time. Results confirm the HPL Index's ability to distinguish pedagogical practices based on HPL principles and pedagogical practices based on traditional, non‐HPL pedagogy.     

815 MHz radio attenuation measured within two commercial buildings

Copolarized attenuation measurements were made at 815 MHz inside two office/laboratory buildings. For the propagation paths along a straight corridor and into a adjoining room received signal power decayed with distance as d^-3.6. Signal powers higher than their free-space values were routinely measured for line-of-sight paths along a corridor. As expected, isolation between floors and between parallel corridors is heavily dependent on building construction techniques. Energy propagates selectively in directions not blocked by large amounts of metal. Cross-floor isolations of 26 dB were measured between floors separated by solid sheet metal. Coupling between otherwise isolated corridors was produced by an open central cavity in the larger building     

Rerandomization tests for analyzing correlated data from dental studies

Dental research studies often produce relatively small data sets in which observations are serially or spatially correlated. Rerandomization tests are presented as alternatives to analysis of variance and multivariate analysis for assessing group differences using such data. Rerandomization tests are particularly useful when the investigator is unwilling to make strong assumptions about the nature of the serial correlation or the distribution of the data. Two examples are discussed that demonstrate these techniques.