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The paper describes a multidisciplinary capstone engineering design course utilizing projects from industry, research programs, and other faculty initiatives. The program involves electrical and mechanical engineering students at Texas Tech University and is team taught by both departments. The structure of the program along with example projects and results is presented.

This paper describes the development of an electrically assisted, hybrid electric vehicle. The mechanical and electrical system modifications required to convert a 1995 Dodge Neon Sedan are presented. Results of dynamic testing with regards to fuel economy, vehicle range, and emissions are presented to illustrate the benefits of operating the vehicle as an HEV.

The antimicrobial efficacy of four commercially available disinfectants (Haz-tabs, chlorhexidine, Virkon and CJ Algisept Spray) was investigated. It was shown that all were effective in decontaminating the impressions whilst those placed only in sterile water, used as a control, showed variable levels of bacterial growth. Moreover, alginate appeared to carry significantly higher numbers of bacteria than addition cured silicone rubber.

Four commercially available disinfectants were tested and the dimensional stability and detail reproduction of impressions and their resultant casts were measured according to ANSI/ISO specifications. Results showed that alginate impressions immersed in chlorhexidine exhibited considerable dimensional change if not poured immediately. Moreover, alginate impressions soaked in a paraldehyde agent (Virkon) for more than 2 minutes produced casts of inferior surface quality whilst those sprayed and left in contact with phenol derivatives (CJ Spray) for 30 minutes resulted in casts which demonstrated statistically and clinically significant dimensional changes. Addition cured silicone impressions exhibited minimal dimensional change regardless of the disinfection regime employed and the resultant casts were accurate with acceptable surface quality.

Wood shaving samples were heated in both cubic baskets and in a previously described system realising the conditions of the ‘infinite slab’ in thermal ignition. Results from the two sets of experiment were found to be totally consistent with each other.

The murine multiple drug resistance (mdr) gene, mdr1a, encodes a 170-kDa transmembrane protein that is expressed in many tissues including intestinal epithelial cells, a subset of lymphoid cells and hematopoietic cells. We report that mdr1a knockout (mdr1a-/-) mice are susceptible to developing a severe, spontaneous intestinal inflammation when maintained under specific pathogen-free animal facility conditions. The intestinal inflammation seen in mdr1a-/- mice has a pathology similar to that of human inflammatory bowel disease (IBD) and is defined by dysregulated epithelial cell growth and leukocytic infiltration into the lamina propria of the large intestine. Treating mdr1a-/- mice with oral antibiotics can both prevent the development of disease and resolve active inflammation. Lymphoid cells isolated from mice with active colitis are functionally reactive to intestinal bacterial Ags, providing evidence that there is enhanced immunologic responsiveness to the normal bacterial flora during IBD. This study is the first description of spontaneous colitis in a gene knockout mouse with an apparently intact immune system. This novel model of spontaneous colitis may provide new insight into the pathogenesis of IBD, the nature of dysregulated immune reactivity to intestinal bacterial Ags, and the potential functional role of mdr genes expressed in the cells and tissues of the colonic microenvironment.

The hemidesmosome is a complex junction containing many proteins. The keratin cytoskeleton attaches to its cytoplasmic plaque, while its transmembrane elements interact with components of the extracellular matrix. Hemidesmosome assembly involves recruitment of alpha 6 beta 4 integrin heterodimers, as well as cytoskeletal elements and cytoskeleton-associated proteins to the cell surface. In our cell culture models, these phenomena appear to be triggered by laminin-5 in the extracellular matrix. Cell interaction with laminin-5 apparently induces both phosphorylation and dephosphorylation of subunits of alpha 6 beta 4 integrin. There is emerging evidence that such events are necessary for subsequent cytoskeleton anchorage to the hemidesmosome cytoplasmic plaque. Once assembled, the hemidesmosome plays an essential role in maintaining firm epithelial adhesion to the basement membrane, with hemidesmosome disruption being a hallmark of certain devastating blistering diseases. However, the hemidesmosome is more than just a stable anchor, as it may also be the site of signal transduction, mediated by its alpha 6 beta 4 integrin component. This review discusses our current knowledge of the structure and assembly of the hemidesmosome.

Analysis of statewide survey data revealed that 22.5% of individuals with mental retardation who were served by the Oklahoma mental retardation system were receiving antipsychotic medication. Anxiolytic medications were prescribed for 9.3%, and antidepressants were prescribed for 5.9%. Higher levels of medication use were found in institutional settings and Intermediate Care Facility settings.

A literature search to identify deleterious effects of using re-refined oil did not disclose any validated occurrences. Significant engine testing using re-refined lubricating oil is reported and no cases were discovered in which engine operation was affected negatively by the use of re-refined oil. The American Petroleum Institute (AFT) allows the use of re-refined base stock oils in the blending of end use lubricants. Based on oil sample testing performed in this research as well as other authoritative sources, it was determined that no significant chemical or physical differences exist between rerefined and virgin oils. Differences noted in this research were related to higher levels of polynuclear aromatics (PNA’s) in the re-refined oil. PNA’s are formed due to the extreme conditions of temperature and pressure during operation of an internal combustion engine. PNA components are essentially removed by the hydrogenation process during re-refining ahd the trace amounts detected in new re-refined oil do not affect the oil’s physical performance characteristics. Similar levels of PNA’s were detected in used re-refined and used virgin oil, thereby indicating that the chemical change during use in an internal combustion engine is independent of the oil used. Lubricating fluid logistics and handling procedures were studied and recommendations related to the screening of suppliers and the use of purchasing specifications to insure the procurement of only qualified supplier’s products are presented. Purchasing specifications are generally acceptable but specific requirements must be stringently enforced to ensure that only quality lubricating products are purchased. Alternative contracting arrangements that offer lubricating fluid procurement and disposal cost savings are suggested. Suppliers have indicated interest in determining cost-effective approachs for supplying lubricants and collecting/disposing of used fluids. Although this research was performed for the Texas Department of Transportation (TxDOT) the recommendations presented are appropriate for other vehicle fleet operators.

Work was sperformed to determine effects of methanol fuel on engine performance and exhaust emissions during long-term use in a 1988 Chevrolet Corsica. Engine wear, gasket performance, fuel economy, emissions level, oil consumption, and overall vehicle performance were monitored over 22,000 miles. Baselines were established at the beginning for comparison: engine was disassembled, bearing/ring clearances and cam profiles were measured. Higher flow rate fuel injectors from AC Rochester were installed and the computer system calibrated for M100 fuel. The vehicle durability test increased oil consumption by 26% under cold-start conditions, 9% under hot start. Oil consumption under hot start was higher than under cold start by as much as 56%; effect of component temperatures on oil viscosity appears to be the cause. It is recommended that oil consumption of a gasoline-fueled vehicle be measured in order to normalize the effect of methanol operation on oil consumption, and to study the effect of steady-state and transient conditions on oil consumption.

In a 5-year prospective study, computed tomographic (CT) morphometry of the lumbosacral vertebral canal was performed on 42 large-breed dogs (21 controls and 21 dogs with lumbosacral stenosis). Dogs were allotted to 4 groups. Group 1 (n = 13) consisted of cadaver specimens obtained from dogs that died or were euthanatized for reasons unrelated to the spine; group 2 (n = 8) consisted of live dogs with no history of clinical signs related to the spine and with normal neurologic examination findings; group 3 (n = 10) consisted of dogs with surgically confirmed lumbosacral stenosis; and group 4 (n = 11) consisted of dogs with suspected lumbosacral stenosis that were managed conservatively. The CT scans were performed, using 5-mm contiguous slices obtained perpendicular to the vertebral canal, from the midbody of the 5th lumbar vertebra through the caudal endplate of the sacrum (L5-S3). Lumbosacral lordosis was minimized in all dogs by positioning them in dorsal recumbency with the hind limbs flexed. A tuberculin syringe calibration phantom was placed within the scanning field of view, parallel to the axis of the spine. In each dog, 11 CT slice locations within the lumbosacral spine were evaluated. At each slice location, sagittal plane diameter, dorsal plane diameter, and transverse area of the vertebral canal, vertebral body, and calibration phantom were measured, using the CT computer's software programs for distance and area calculation. Window/level settings were constant, and all measurements were made by the same operator (JCJ). Accuracy of calibration phantom CT measurements was 100% for sagittal and dorsal plane diameter and was 85% for transverse area.(ABSTRACT TRUNCATED AT 250 WORDS)

Although sphenoidal electrodes are widely used to detect epileptiform activity, there is no agreement on an optimal target to which electrodes should be aimed. The purpose of this study was to determine whether fluoroscopic guidance is a reliable method for placing electrodes directly below the foramen ovale and whether such positioning enhances their capacity to detect epileptiform activity when compared to similar electrodes placed blindly into the infratemporal fossa. We examined the surface/sphenoidal EEG recordings of 17 patients with intractable partial seizures of anterotemporal origin, after fluoroscopically placed sphenoidal electrodes (FPSE) had been inserted to lie just below the foramen ovale. A criterion for eligibility was a previous prolonged video/EEG monitoring with blindly placed sphenoidal electrodes (BPSE) that failed to detect seizures with a focal onset. No blindly placed electrode, for which there was radiographic documentation, reached the foramen ovale. Fluoroscopic guidance assured accurate targeting. FPSE detected a unilateral anterotemporal interictal focus in four patients in whom BPSE had failed to record any interictal spikes and detected bitemporal independent interictal foci in one patient in whom BPSE had identified only unilateral spikes. In nine other patients, the spike count obtained with FPSE recordings increased by100% when compared to that obtained with BPSE recordings. FPSE recorded seizures with an anterotemporal focal onset pattern in 10 patients in whom BPSE had recorded seizures with a regional, lateralized, or nonlocalized onset pattern. In nine of these 10 patients, this was adequate to recommend surgery and avoid invasive monitoring. Fluoroscopic guidance assures accurate targeting of the foramen ovale. When compared to BPSE, FPSE resulted in better detection of interictal and ictal epileptiform activity of mesial-basal-temporal origin.

The sealing ability of four restorative materials, placed in root surface cavities, was assessed by a range of standard in vitro microleakage tests. The rank order of the severity of microleakage associated with the four materials varied with the different tests. Although differences between the performance of unlined amalgam, two different dentine-bonded composites and a glass-ionomer restorative material were detected, most were not statistically significant. None of the materials tested completely eliminated microleakage and so even those materials reported to be adhesive to dentine cannot be considered ideal in the restoration of root surface cavities.

We have analyzed gene-specific and strand-specific DNA damage and repair in the dihydrofolate reductase gene in hamster cells. Cells were UV-irradiated or treated with two types of chemotherapeutics, alkylating agents or cisplatin. UV-induced pyrimidine dimers were detected using a previously published technique in which the T4 endonuclease V enzyme is used to create nicks at the lesion sites. 6-4 photoproducts were detected in a similar assay using ABC excinuclease after prior reversal of the pyrimidine dimers with photolyase. Adducts formed by the alkylating agents nitrogen mustard and dimethyl sulfate were quantitated by generating strand breaks at basic sites after neutral depurination. Cisplatin-induced intrastrand adducts were detected with ABC excinuclease, and cisplatin interstrand cross-links were detected using a denaturation-reannealing reaction before electrophoresis. In accord with previous reports by other investigators, we find distinct strand specificity of the repair of pyrimidine dimers after UV; the transcribed strand was much more efficiently repaired than the nontranscribed strand. In contrast, there was little or no strand bias in the repair of the 6-4 photoproducts. For alkylating agents, a slight bias toward repair in the transcribed strand was found after treatment with nitrogen mustard, but there appeared to be no bias in the repair after treatment with dimethyl sulfate. Cisplatin interstrand cross-links are repaired with equal efficiency from the two strands, but the more common cisplatin-induced lesion, the intrastrand adduct, is preferentially repaired from the transcribed strand. In conclusion, there is strand bias in the repair of pyrimidine dimers and cisplatin intrastrand adducts, but the strand specificity of repair may not be a general feature for all DNA lesions, as we found little or no strand bias in the repair of other lesions studied.

We sought to determine whether the recently reported decreased incidence of stroke and atherosclerotic disease in a university hospital-based Parkinson's disease patient population would be demonstrated in our patient population. We performed a retrospective case-control review of the last 119 Parkinson's disease patients discharged from the Middleton Veterans Affairs Hospital Neurology Service to study the incidence of ischemic stroke, myocardial ischemia, tobacco use, and other stroke risk factors. Controls were age and sex matched and were randomly taken from 238 non-Parkinson's disease discharges in which stroke or myocardial infarction was not the reason for hospitalization. The cumulative incidences of ischemic stroke, hypertension, and diabetes mellitus were not significantly different between groups. Myocardial infarction, coronary artery disease, tobacco use, atrial fibrillation, cancer, and ethanol abuse were significantly more prevalent in the controls, whereas dementia and congestive heart failure were the only variables studied that were more prevalent in the Parkinson's disease patients. Our study failed to demonstrate that Parkinson's disease patients from a Veteran population were protected from ischemic stroke.

The adhesion complex of the corneal epithelium consists of the hemidesmosome and its associated structures, such as anchoring filaments, lamina densa of the basement membrane, and anchoring fibrils. It contributes to the adhesion of the corneal epithelium to Bowman's layer. To understand the adhesion complex better, an electron microscopic and immunofluorescence analysis was done of the reformation of the adhesion complex in small (1 mm) keratectomy wounds in the guinea pig cornea. In these wounds, the epithelium, hemidesmosomes, basal lamina, anchoring fibrils, and anterior stroma were removed. The wound bed was epithelialized completely by 24 hr after wounding. Immunofluorescence analyses involved the use of antibodies against plaque components of the hemidesmosome, an antibody against laminin, and an antibody against the collagen VII component of anchoring fibrils. At 18 hr after wounding, there was no morphologic evidence of hemidesmosomes at the epithelial-stromal interface. At 24 hr, hemidesmosomes were observed, with or without subjacent lamina densa. Furthermore, plaque components were detected by immunofluorescence in those cells in contact with the wound bed. In contrast, no type VII collagen was detected. On day 7, collagen VII, laminin, and bullous pemphigoid autoantibody markers colocalized along the wound bed as determined by immunofluorescence. However, at the ultrastructural level, even though the lamina densa of the basal lamina was observed primarily where hemidesmosomes were present, it remained incomplete. In this study, the precise temporal sequence in which components are incorporated into the assembling adhesion complex was described during wound healing. Furthermore, the possibility that the hemidesmosomal plaque nucleates the formation of the underlying basal lamina was discussed.

Latex agglutination (LA) tests are ordered frequently on cerebral spinal fluid (CSF) specimens obtained from pediatric patients to identify pathogenic bacteria as early as possible in an acute infection.Six hundred ten LA tests were performed on 176 patients suspected of having meningitis.Five patients with meningitis had positive LA tests. We found that the CSF white blood cell (WBC) count, and differential were the best predictors of meningitis.By limiting the use of LA tests to those patients having CSF with abnormal WBC counts or with positive Gram stains, the number of tests ordered would have been reduced. This practice would greatly reduce laboratory expense.

A data base documenting information on approximately 600 fluids and materials processing experiments performed in a low-gravity environment has been prepared at NASA Marshall Space Flight Center (MSFC). The compilation was designed to document all such experimental efforts performed: (1) on U.S. manned space vehicles; (2) on payloads deployed from U.S. manned space vehicles; and (3) on all domestic and international sounding rocket programs (excluding those of the U.S.S.R. and China). Identification of major (reported) sources of significant anomalies during 100 of the experiments is reported and discussed. Further, a preliminary summary of the number of these 100 investigations which experienced an anomaly affecting a certain percentage of the experimental results/objectives is presented.

We have used three methods to study the formation and repair of intrastrand adducts and interstrand cross-links in the DNA of Chinese hamster ovary cells induced by the anticancer drug cis-diamminedichloroplatinum II (cisplatin). Using atomic absorption spectroscopy, we found that 21% of the total genomic cisplatin adducts were removed at 8 h and 42% at 24 h. We used ABC excinuclease digestion, coupled with out previously reported methodology to quantify DNA in specific genomic regions. These adducts were removed faster in the transcribed dihydrofolate reductase and c-myc genes compared to a noncoding fragment, a region containing the little or nontranscribed c-fos oncogene, and to the overall genome. Interstrand cross-links in specific sequences were quantified by Southern hybridization of denatured-renatured DNA separated on a neutral gel. We found that cross-links were removed more efficiently from the gene regions than intrastrand adducts and, at high levels of cross-linking, removal was similar from transcribed and from nontranscribed regions.

According to the concept of keratin pairing defined by tissue coexpression, a 55-kD/64-kD keratin pair is a marker of "corneal-type" differentiation. Intermediate filament (IF)-enriched preparations from guinea pig and bovine corneal epithelium were analyzed, and a rabbit antiserum was generated against a 55-kD polypeptide enriched in these preparations. This antiserum generated a typical IF-like pattern in cultured bovine corneal epithelial cells. Immunofluorescence microscopic analysis of frozen sections of guinea pig and bovine tissue revealed that the 55-kD antiserum labeled corneal and limbal epithelium. In addition, the antiserum stained a subpopulation of peripheral limbal cells that were distributed in both basal and suprabasal layers of the epithelium. The monoclonal antibody AE5 was used to investigate the distribution of the 64-kD polypeptide in guinea pig and bovine tissue. Immunoblotting analysis revealed that AE5 antibodies recognized a 64-kD polypeptide in guinea pig cornea, but recognized a 66-kD polypeptide in bovine cornea. Immunofluorescence microscopic analysis of guinea pig tissue revealed that AE5 antibodies labeled suprabasal layers of corneal epithelium, in suprabasal layers of limbal epithelium, and in groups of cells in the peripheral limbal epithelium. We discuss the possibility that the ocular epithelial cells recognized by either the 55-kD or the 64-kD antibodies in the peripheral limbus may play a role in the reepithelialization of the cornea after wounding.

This is the first of a series of mini-essays by Dr J. C. Jones that will be published in the next few issues. These have been peer reviewed to a degree appropriate to ‘notes’ rather than full articles. It is hoped that they will engender discussion, and readers with responses to any particular mini-essay are encouraged to contact Dr Jones himself or the journal editor. It is also believed that they will provide teaching material, in which case acknowledgement is requested. Editor

Describes a link between greenhouse gases, the black body concept, and the Stefan–Boltzmann law that is pedagogically interesting and might be of value to others teaching physical chemistry.

The one possible exception to the view that detonations are not expected from hydrocarbons or their derivatives under conditions of industrial processing is organic peroxides.

Rolling noise from trains is radiated by both wheel and track vibrations, the track being dominant in many cases. The stiffness of the rail fastener system, especially the elastomeric rail pad usually inserted between the rails and the sleepers, has a significant influence on the noise emitted by the track. Railways are increasingly using softer pads to reduce potential damage to sleepers and ballast. Softer pads decouple the rail from the sleeper. This reduces the noise from the sleeper but also reduces the decay of vibration with distance along the rail and hence leads to an increase of the noise radiated by the rail. The paper describes experimental and theoretical work to investigate the influence of pad stiffness on the dynamic and acoustic behavior of track. The vibrational behavior has been measured on a dedicated 36‐m section of railway track, with different types of rail pad installed. The results are compared with predictions using theoretical models of the track behavior. This allows the effective pad stiffness and damping to be determined, laboratory measurements also being available for comparison. The attenuation of vertical and lateral vibration along the track is measured in order to estimate the effect on radiated noise.

The performance of ferroelectric liquid crysta displays are particularly sensitive to achieving the correct alignment conditions. Topographical studies of the surface layers of a colour FLCD have been made using tapping mode atomic force (AFM). The results are compared with detailed studies of test cells at different stages of device fabrication. An understanding of the relationship between the nanoscopic structure of the surfaces and the bulk alignment of the liquid crystal is developed. This enables device properties such as speed, contrast and viewing angle to be improved uniformly over the panel.