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Bone Regeneration Materials For The Mandibular And Craniofacial Complex, Jeffrey Hollinger, Anshumali Chaudhari

Cells and Materials

Due to different functional demands and vascularity, the mandibular and craniofacial complex require bone regenerating materials with physical and chemical properties that are different from long bone. However, certain common requirements to both locales must be addressed. Furthermore, reasons why the autograft and allogeneic bank bones are successful in regenerating bone need to be understood if the researcher is to develop satisfactory alternatives. The purpose of this paper is to review some of the requirements needed for bone regenerating materials for mandibular and craniofacial bone repair. In that effort, we have briefly described the autograft and allogeneic bank bones, animal …

Changes In Intracellular Ca2+ And Structure In Platelets Contacting Synthetic Substrates, L. M. Waples, O. E. Olorundare, S. L. Goodman, R. M. Albrecht

Cells and Materials

Platelet structural changes such as spreading and cytoskeletal reorganization that occur upon contact with synthetic surfaces have been well documented . Structural changes such as spreading will vary depending on the substrate involved . Although platelet structural changes following adhesion have been recorded , the cellular mechanisms including changes in intracellular calcium flux underlying these platelet responses are less well understood. In this study, video microscopy was used to image platelet adhesion and spreading while simultaneously imaging intracellular free Ca2+ levels in individual Fura-2 loaded human platelets. This was accomplished using fluorescence video microscopy coupled with video enhanced asymmetric illumination …

Clinical Applications Of Recombinant Gene Technology: Bone And Cartilage Repair, Thomas A. Einhorn

Cells and Materials

Over the past decade, the field of molecular biology has given rise to the development of the applied discipline of molecular medicine. Based on recent developments using recombinant gene technology, genetic mapping analysis and other investigational tools, the physician and surgeon is now ready to begin using those instruments in the diagnosis and treatment of musculoskeletal disease. This article reviews the history of scientific exploration in recombinant gene technology as it applies to bone and cartilage repair. Clinical cases are presented to show how the fruits of scientific knowledge may be brought to bear on some of the more challenging …

Reactogenicity Of Biomaterials As Studied By Biochemical, Morphological And Ultrastructural Techniques, Leonid I. Slutskii, Natalya A. Sevastjanova, Ivetta L. Ozolanta, Irina V. Kuzmina, Laimdota E. Dombrovska

Cells and Materials

Reactogenicity is a characteristic of biocompatible materials that provokes the reparative and proliferative reaction of connective tissues, a compulsory stage of which is inflammation. Thus, reactogenicity studies should include experiments in vivo. A quantitative assessment of reactogenicity can be obtained by subcutaneous implantation of standard olive-shaped specimens covered by the biomaterial under study followed by biochemical, histological and scanning electron microscopical studies of the capsule developing around the implant. Reactogenicity of surgical threads is evaluated by semiquantitative histological analysis of the wound healing process after suture application. Biomaterial reactogenicity can be modified by changing the structure of the surface and …

Apatite - Cholesterol Agglomerates In Human Atherosclerotic Lesions, Sara Sarig, Danielle Hirsch, Reuven Azoury, Teddy A. Weiss, Iony Katz, Howard S. Kruth

Cells and Materials

The purpose of this study was to examine the ultrastructural relationships of cholesterol crystals and apatite deposits in human atherosclerotic lesions. Segments of human aortic atherosclerotic lesions were obtained at autopsy , fixed in glutaraldehyde and dehydrated without using any organic solvents. The aortic segments were coated with carbon and subjected to various scanning electron microscope analyses. These included secondary electron imaging, back scattering of primary electrons, energy dispersive X-ray analysis of selected spots followed by area mapping of calcium and phosphorus , and cathodoluminescence.

The information gathered from scanning of selected areas in the lesions by all the techniques …

Review: Biomaterials For Abdominal Wall Reconstruction, Roger K. J. Simmermacher, Robert P. Bleichrodt, Jeff M. Schakenraad

Cells and Materials

The reconstruction of large abdominal wall defects still is a major surgical problem. Many different techniques have been developed for this purpose, most of which appeared to be unsatisfactory. The lack of sufficient tissue requires the insertion of prosthetic material. Non-absorbable prostheses used to reconstruct abdominal wall defects showed the best results . Polypropylene mesh (PPM) and expanded polytetrafluoroethylene (ePTFE) soft-tissue patch are the most frequently used materials for this purpose . However, PPM induces extensive visceral adhesions and erosion of the skin, whereas ePTFE is insufficiently anchored to the adjacent tissue and therefore both materials are not ideal. As …

Switching To Photonics, Harvard S. Hinton

Electrical and Computer Engineering Faculty Publications

The use of hardware that exploits the interplay of photons and electrons to switch voice, data, and video is discussed. The two directions being taken by current research-guided-wave and free-space photonics-are examined. Photonic time-slot interchanges are described. Multidivisional fabrics, based on a combination of space-division and time-division multiplexing, are considered, as is the wavelength-division-based photonic packet switch, another kind of multidimensional fabric. The use of self-electrooptic effect devices, (SEEDs) is discussed.

Interaction Of Liposomal Drug Delivery Systems With Cells And Tissues: Microscopic Studies, M. Foldvari, G. T. Faulkner, C. Mezei, M. Mezei

Cells and Materials

Liposomes , as drug carriers, can be administered into the body by several routes e.g. intravenously, intraperitoneally, intramuscularly, intratracheally and topically among others. Radiolabelled markers are suitable to monitor the distribution and elimination of liposomes, but the tissue deposition of intact liposomes, the mode and sites of drug release from the liposomes and liposome-cell interactions cannot be investigated morphologically. Microscopic techniques could provide information regarding the intact state of liposomes and possibly the dynamics of liposomes in tissues provided that they can be identified with certainty in vivo. This is a formidable problem and in spite of several attempts, there …

Evaluation Of Bacterial Glycocalyx Preservation And Staining By Ruthenium Red, Ruthenium Red-Lysine And Alcian Blue For Several Methanotroph And Staphylococcal Species, Theresa A. Fassel, James E. Van Over, Christopher C. Hauser, Lorie E. Buchholz, Charles E. Edmiston, James R. Sanger, Charles C. Remsen

Cells and Materials

The cationic reagents, ruthenium red (RR), alcian blue (AB) and ruthenium red -lysine were compared for ultrastructural preservation and staining of the bacterial glycocalyx. En bloc RR, AB and RR-lysine procedures, and a glutaraldehyde/OsO4 fixation withou t cationic reagent, were evaluated by transmission electron microscopy (TEM) for several methanotroph and staphylococcal species. The glutaraldehyde/OsO4 fixation was totally ineffective in preserving or staining the glycocalyx material in all species studied. The RR procedure was more effective than the glutaraldehyde/OsO4 fixation but was generally less so than the RR-lysine procedure. By the RR-lysine procedure, extensive layers that were often filamentous or fibrous …

Hydraulic Structures Versus Zebra Mussels, John J. Ingram, Andrew C. Miller

United States Army: Publications

The United States Army Corps of Engineers (USAE) has begun a four-year research program to develop environmentally sound control strategies for zebra mussel (Dreissena polymorpha) infestations at public facilities. The USAE Waterways Experiment Station has initiated research for these facilities which include water-intake structures, navigation locks, gated dams, outlet works, pumping plants, hydropower plants, drainage structures, dredges and commercial vessels.

Pesticide Application And Handling Technology: Decreasing Drift Potential During Application, G. A. Watkins, Samuel G. Mcneill, James R. Martin, S. A. Shearer

Agricultural Engineering Extension Updates

Accidental spray drift from pesticide applications can result in dangerous conditions for humans, animals, and the environment. It also can mean extra costs for the applicator due to wasted chemical and inefficient applications. Although complete elimination of spray drift is nearly impossible, drift problems and their effects on our environment can be minimized with proper application techniques and favorable weather conditions.

Kentucky Traffic Accident Facts 1992 Report, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY'S TRAFFIC ACCIDENT FACTS report for 1992 is based on accident reports submitted to the Accident Unit housed in the Kentucky State Police Information Services Branch, Records Section. As required by Kentucky Revised Statutes 189.635, "every law enforcement agency whose officers investigate a vehicle accident of which a report must be made .. . shall file a report of the accident ... within ten days after investigation of the accident upon forms supplied by the bureau.· The stated purpose of this requirement is to utilize data on traffic accidents" for such purposes as will improve the traffic safety program in …

Bulletin No 4131- Electric Fencing, Dean Maughan

Bulletins 4000 -

Fencing has always been an integral part of our agricultural system. We need fences for stock control and pasture management. Traditionally, fences have been strong and robust physical barriers. The strength and height of the fence kept domestic animals confined. For many years, conventional fences have served the farmer well. However because returns from livestock over the past ten years have been variable and because of the current cost/ price squeeze, electric fencing, as a cheaper form of fencing, has gained popularity.

Oxygen Radicals In Ulcerative Colitis, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This article reviews the pathophysiologic concept that superoxide and hydrogen peroxide, generated by activated leukocytes, together with low-molecular-weight chelate iron derived from fecal sources and from denatured hemoglobin, amplify the inflammatory response and subsequent mucosal damage in patients with active episodes of ulcerative colitis. The putative pathogenic mechanisms reviewed are as follows: ( l ) Dietary iron is concentrated in fecal material owing to normally limited iron absorption. (2) Mucosal bleeding, characteristic of ulcerative colitis, as well as supplemental oral iron therapy for chronic anemia, further conspire to maintain or elevate mucosal iron concentration in colitis. (3) Fenton chemistry, driven …

Histochemical Demonstration Of Endothelial Superoxide And Hydrogen Peroxide Generation In Ischemic And Reoxygenated Rat Tissues, Charles F. Babbs, Meloney D. Cregor, Stephen F. Badylak

Weldon School of Biomedical Engineering Faculty Publications

Objective: The aims were to test and evaluate two novel and independent histochemical methods for detecting the initial postischemic burst of superoxide and hydrogen peroxide in buffer perfused rat tissues during reflow after 60 min warm ischemia. Methods: The first is a high manganese/diaminobenzidine technique, in which superoxide oxidises Mn2+ to Mn3+, which in turn oxidizes diaminobenzidine to form amber colored polymers, observable by light microscopy. The second is a high iron/diaminobenzidine technique, in which hydrogen peroxide oxidizes diethylenetriaminepenta-acetate chelated Fe2+ to form intermediate species, which in turn oxidize diaminobenzidine similarly to Mn3+. Various isolated organs of the rat were …

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Building Services Engineering

No abstract provided.

Final Environmental Assessment For Endangered Species Habitat Enhancement/Creation Along Tile Missouri River Main Stem System

United States Army Corps of Engineers, Omaha District

The interior least tern (Sterna antillarum) and the piping plover (Charadrius melodus) are federally endangered and threatened species, respectively, which nest on sandbars in the Missouri River. This nesting habitat has been decreasing in past years, at least in part due to vegetative encroachment. Vegetation is no longer regularly scoured from sandbars by heavy spring flows and/or ice, primarily because flows are regulated by the main stem dams. New sandbar creation is uncommon because the river carries less sediment and is no longer meandering along much of its course. Bank erosion still continues to supply sediment …

Management Of Feedlot Runoff Control Systems, Elbert C. Dickey, Gerald R. Bodman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

During recent years, most open feedlot operators have found it desirable and, in some cases, necessary to install runoff control facilities. Even though the primary purpose of feedlot runoff control systems is the prevention of water pollution, many producers have found that good management of these systems also offers limited economic benefits in the form of fertilizer nutrients and supplemental irrigation water. Well managed runoff control systems also reduce weeds, odors, insects and muddy areas at or near feedlot edges. The runoff control system that has proved most satisfactory for all areas of the country is one consisting of clean …

Evaluation Of Mechanisms Of Alteration And Humification Of Pahs For Water Quality Management, Ronald C. Sims, Carolyn K. Abbott

Reports

Introduction: Creosote-pentachlorophenol (PCP) is a mixture commonly used as a wood preservative in the U.S. (1). A 1988 survey (2) indicated that 1,397 wood preserving waste contaminated sites exist in the United States consisting of 555 active wood treatment plants and 842 inactive plants. Stinson (3) indentifed 58 wood preserving sites on the National Priorities List, of which 51 have PCP and/or creosote or polycyclic aromatic hydrocarbon (PAH) contamination. Principal classes of organic constituents present in creosote waste are PAHs (~85% by weight) and phenolics. PAHs with less than three fused benzene rings comprise 69% (i.e., naphthalene, anthracene and phenanthrene); …

A Case Study On Petri Net Modeling, Animation, And Simulation, Suresh C. Gurala

Theses

Petri nets as a graphical tool has developed over the last decade into a suitable model for representing, modeling, designing, analyzing and studying concurrent systems. In this thesis, Petri nets are applied for analyzing, modeling and simulation of a flexible assembly station. An existing AT&T FWS200 flexible assembly workstation for printed circuit board is modeled using Petri nets without the consideration of insertion failures and other abnormalities in the system. The Petri net model is then simulated using Graphics simulation language (GSL).

Temperature Regulation Post Hemorrhagic Shock In Rats : Atheoretical Analysis, Kahambwe Shungu

Theses

The adequacy of a mathematical model in simulating temperature regulation in rats after resuscitation from hemorrhagic shock is investigated. This model, proposed elsewhere, was devised to study temperature profiles during hyperthermia in humans.

Hemorrhagic shock was achieved by bleeding rats to an average mean arterial pressure (MAP) of 30mmHg. The rats were then maintained at this MAP for up to four hours by withdrawing or reinfusing the shed blood. One group (the control group), was allowed to return to normal body temperature after the shock episode without external intervention. A second group (microwave group) was irradiated, for an average of …

Image Deblurring For Visualization Of Coronary Microcirculation, Kaijun Wang

Theses

Blurred images of the rat coronary microcirculation have been obtained and processed. Heart motion, blood flow and noise cause the blur of the images. The objective of this thesis work was to study the effects of these factors on image quality and assess several models for image deblurring. The Wiener Filter and the Powei Spectrum Equalization Filter were implemented and were added to the existing image processing software. The images obtained after the application of these filters showed significant improvement over the original blurred images.

Study Of A Non-Contact Gaging System Of Inspection, Gordhanbhai Ketan Patel

Theses

The quality control function has traditionally been performed using manual inspection methods and statistical sampling procedures. Manual inspection is generally a time - consuming procedure which involves precise, yet monotonous work. It often requires that parts be removed from the vicinity of the production machines to a separate inspection area. This causes delays and often constitutes a bottleneck in the manufacturing schedule.

As a solution to the above problem a Non - Contact Gaging System developed by Optical Gaging Products, Inc., has been used here to study the feasibility of using an automated inspection system and a procedure of developing …

A Graphic Editor And Real Time Simulator Of Petri Net, Tenian Tang

Theses

A structurally designed graphic editor and real time simulator of Petri nets (PN) is presented. The package is programmed by Turbo C language, which runs in IBM-PC environmental with graphics adaptor. Various kinds of PN systems such as ordinary, general and timed Petri net can be modeled and analyzed by firing the models with real time token movement animations. Some properties of analyzed PN such as reachability, deadlock, firing time can be studied. Several illustrative examples are presented. The possible further enhancements are also discussed.

Structured Hypermedia Application Development Model (Shadm): A Structured Model For Technical Documentation Application Design, Peter W. Cassell

Theses and Dissertations

This research was conducted to determine how a Royal Australian Air Force technical maintenance publication could be transformed into a task oriented hypermedia application and to develop a model that could be used for future similar transformations. The model was developed following in-depth analysis of the existing USAF F-15E maintenance publication set and validation was conducted using a prototype developed in HyperWriter, a commercial hypermedia product. The prototype model was based around the performance of three maintenance tasks on an aircraft sub-subsystem and incorporated online user access to the necessary support data for task completion. Publication managers, producers, and users …

Binaural Sound Localization Using Neural Networks, Rushby C. Craig

Theses and Dissertations

The purpose of this study was to investigate the use of Artificial Neural Networks to localize sound sources from simulated, human binaural signals. Only sound sources originating from a circle on the horizontal plane were considered. Experiments were performed to examine the ability of the networks to localize using three-different feature sets. The feature sets used were: time-samples of the signals, mena Fast Fourier Transform magnitude and cross correlation data, and auto-correlation and cross correlation data. The two different types of sound source signals considered were tones and gaussian noise. The feature set which yielded the best results in terms …

Image Analysis Using Gabor Transforms: Correlated With Human Saccadic Movement Data To Identify The Human Visual Search Strategy, Ralph J. St John

Theses and Dissertations

This thesis investigated whether a relationship exists between the Gabor Correlation Coefficient (GCC) magnitudes of fixation points for a set of images viewed by six subjects and the human visual search strategy. A couple of different relationships were investigated. First, the data were analyzed to determine if the GCC magnitudes of human fixation points predicted the time ordered sequence of human fixation points during the performance of a visual search. Second, the data were analyzed to determine if there was a significant difference between the GCC magnitudes of the human fixation points and the GCC magnitudes of a random set …

Face Recognition With The Karhunen-Loeve Transform, Pedro F. Suarez

Theses and Dissertations

The major goal of this research was to investigate machine recognition of faces. The approach taken to achieve this goal was to investigate the use of Karhunen-Loe've Transform (KLT) by implementing flexible and practical code. The KLT utilizes the eigenvectors of the covariance matrix as a basis set. Faces were projected onto the eigenvectors, called eigenfaces, and the resulting projection coefficients were used as features. Face recognition accuracies for the KLT coefficients were superior to Fourier based techniques. Additionally, this thesis demonstrated the image compression and reconstruction capabilities of the KLT. This theses also developed the use of the KLT …

A Topographical Analysis Of The Human Electroencephalogram For Patterns In The Development Of Motion Sickness, George S. Vogen

Theses and Dissertations

A topographical analysis was performed on 12 electroencephalograms (EEGs) collected from 10 volunteers who experienced motion sickness through cross-coupled Coriolis stimulation. Seven males and three females participated in the research conducted at the Air Force Institute of Technology, Wright- Patterson AFB. Two male volunteers participated in double-blind placebo/ phenytoin trials. Static brain maps and dynamic EEGs which focused on delta (below 3Hz) activity during the development of motion sickness revealed a seizure-like propagation pattern. With initial symptoms, a clear left parietal focus was seen in all records. A less dominant left fronto-temporal focus was present in 11 of the 12 …

The Application Of Statistical Kriging To Improve Satellite Imagery Resolution, Donald W. Mcgee Jr.

Theses and Dissertations

Imagery analysts are always looking for improved methods of analyzing digital satellite imagery. The resolution of satellite imagery can be improved by enlarging the images since the result will be a higher degree of discernable detail. Currently, nearest-neighbor, bilinear interpolation, and cubic convolution techniques are used for this purpose. The nearest-neighbor technique produces block-like images. The latter two methods produce sharp imagery, but the original information contained in the pixel values is changed in the process of convolving the image. These techniques cannot, therefore, be considered true representations of the original image. Kriging is a statistical technique which can be …