Some Aspects of Gastrointestinal Adaptation to Obstruction of the Small Intestine: Modulating Role of Diet

The "well being" of the gastrointestinal tract is maintained by the interplay of several -factors, notably diet, pancreatic and biliary secretions and gastrointestinal hormones. These same factors may be responsible for enabling the organ to adapt to chanqing circumstances. To date, most of what is known about gastrointestinal adaptation has been derived from animal experimentation and the progress in this field has, to some extent, been limited by the suitability of the animal models. One such example is the adaptive response of the gastrointestinal tract to small intestinal obstruction. Whereas a wealth of information exists regarding adaptation to acute obstruction, knowledge of the changes to the chronic event is limited. The first aim of the thesis was therefore to further develop and modify a reproducible model of chronic small bowel obstruction in the rat. The study was then extended to investigate the changes in both the proximal (i.e. oesophagus, stomach and proximal small intestine) as well as the distal (i.e. distal small intestine) bowel to obstruction. In addition, the presence and absence of food bulk on these changes was also investigated. The gastrointestinal hormone profiles under each experimental condition were also identified. It was found that: 1. An increase in oesophageal weight occurred following a high small bowel obstruction. Other levels of small bowel obstruction had no noticeable effect on the oesophagus. 2. The response of the stomach to obstruction varied with the site of the small bowel obstruction. A high obstruction produced a marked dilatation of the stomach. A mid small intestinal obstruction generated marked gastric muscle hypertrophy. 3. The jejunum and the ileum behaved in a similar fashion in that both showed an increase in weight and and in luminal circumference in response to obstruction. However the magnitude of the ileal response was far greater. 4. The administration of a low residue diet did not result, during the time period of the experiment, in a reduction of the mucosal weight of the gastrointestinal tract. However a reduction in both the DNA and protein concentration was observed. When this low residue diet was administered to rats subjected to a small bowel obstruction, the hypertrophic response noted in chow-fed obstructed animals was abolished. 5. Disuse atrophy of the mucosa was seen in the ileum of rats with a mid small bowel obstruction fed on chow. Although some degree of atrophy did occur in similarly obstructed rats fed on a low residue diet, the degree of atrophy was significantly less than that in chow fed obstructed animals. 6. Hormonal assays showed that: a. Serum gastrin was raised following a high obstruction and following the administration of a low residue diet. b. Serum N-glucagon levels showed significant increases following mid and distal small bowel obstruction. c. Vasoactive intestinal peptide levels were increased following a distal obstruction

NASA-ASEE Summer Faculty Fellowship Program at NASA Lewis Research Center

During the summer of 1996, a ten-week Summer Faculty Fellowship Program was conducted at the NASA Lewis Research Center (LeRC) in collaboration with Case Western Reserve University (CWRU), and the Ohio Aerospace Institute (OAI). This is the thirty-third summer of this program at Lewis. It was one of nine summer programs sponsored by NASA in 1996, at various field centers under the auspices of the American Society for Engineering Education (ASEE). The objectives of the program are: (1) to further the professional knowledge of qualified engineering and science educators, (2) to stimulate an exchange of ideas between participants and NASA, (3) to enrich and refresh the research activities of participants' institutions. (4) to contribute to the research objectives of LeRC. This report is intended to recapitulate the activities comprising the 1996 Lewis Summer Faculty Fellowship Program, to summarize evaluations by the participants, and to make recommendations regarding future programs

NASA Space Engineering Research Center Symposium on VLSI Design

The NASA Space Engineering Research Center (SERC) is proud to offer, at its second symposium on VLSI design, presentations by an outstanding set of individuals from national laboratories and the electronics industry. These featured speakers share insights into next generation advances that will serve as a basis for future VLSI design. Questions of reliability in the space environment along with new directions in CAD and design are addressed by the featured speakers

A Study of G Protein Coupled Signal Transduction Mechanisms in Alzheimer's Disease

The specific objective of the work described in this thesis was to study aspects of signal transduction in the post mortem brains of persons who had suffered from dementia of the Alzheimer type (DAT). There already exists much data describing the state of many neurotransmitter systems in the disease, but little information was available regarding the events that take place subsequent to receptor activation. Such knowledge is important in order to assess the potential for neurotransmitter replacement therapies in the treatment of Alzheimer's disease, as well giving further insight into the neurodegenerative mechanism of this disease. The levels of the guanine nucleotide binding protein (G protein) a subunits, GsH, GsL, Gil, Gi2 and Gsa, were measured by western blotting utilising highly specific anti-G protein antisera. Similarly, the messenger RNA (mRNA) encoding the G protein subunits Goa, Gia and GB, as well as 28S ribosomal RNA (28S mRNA), were analysed by northern blotting utilising radiolabelled oligonucleotide probes. In addition, the activities of the enzymes adenylate cyclase, sodium potassium dependent ATPase and choline acetyl transferase were assayed using standard methods. (i) Effect of post mortem delay on different components of signal transduction in rat brain. Since multiple parameters (e. g. levels of G proteins and their mRNAs, adenylate cyclase activity, etc. ) were to be measured in post mortem human tissue, there was a concern that the delay between death and freezing of the tissue (the post mortem delay) would influence the reliability of any measurements made. This possibility was investigated by experiments in which rats were sacrificed and left at room temperature for 24 hours, or at

Computer-based tools for supporting forest management. The experience and the expertise world-wide

Report of Cost Action FP 0804 Forest Management Decision Support Systems (FORSYS)Computer-based tools for supporting forest management. The experience and the expertise world-wide answers a call from both the research and the professional communities for a synthesis of current knowledge about the use of computerized tools in forest management planning. According to the aims of the Forest Management Decision Support Systems (FORSYS) (http://fp0804.emu.ee/) this synthesis is a critical success factor to develop a comprehensive quality reference for forest management decision support systems. The emphasis of the book is on identifying and assessing the support provided by computerized tools to enhance forest management planning in real-world contexts. The book thus identifies the management planning problems that prevail world-wide to discuss the architecture and the components of the tools used to address them. Of importance is the report of architecture approaches, models and methods, knowledge management and participatory planning techniques used to address specific management planning problems. We think that this synthesis may provide effective support to research and outreach activities that focus on the development of forest management decision support systems. It may contribute further to support forest managers when defining the requirements for a tool that best meets their needs. The first chapter of the book provides an introduction to the use of decision support systems in the forest sector and lays out the FORSYS framework for reporting the experience and expertise acquired in each country. Emphasis is on the FORSYS ontology to facilitate the sharing of experiences needed to characterize and evaluate the use of computerized tools when addressing forest management planning problems. The twenty six country reports share a structure designed to underline a problem-centric focus. Specifically, they all start with the identification of the management planning problems that are prevalent in the country and they move on to the characterization and assessment of the computerized tools used to address them. The reports were led by researchers with background and expertise in areas that range from ecological modeling to forest modeling, management planning and information and communication technology development. They benefited from the input provided by forest practitioners and by organizations that are responsible for developing and implementing forest management plans. A conclusions chapter highlights the success of bringing together such a wide range of disciplines and perspectives. This book benefited from voluntary contributions by 94 authors and from the involvement of several forest stakeholders from twenty six countries in Europe, North and South America, Africa and Asia over a three-year period. We, the chair of FORSYS and the editorial committee of the publication, acknowledge and thank for the valuable contributions from all authors, editors, stakeholders and FORSYS actors involved in this project

Conference on Intelligent Robotics in Field, Factory, Service, and Space (CIRFFSS 1994), volume 1

The AIAA/NASA Conference on Intelligent Robotics in Field, Factory, Service, and Space (CIRFFSS '94) was originally proposed because of the strong belief that America's problems of global economic competitiveness and job creation and preservation can partly be solved by the use of intelligent robotics, which are also required for human space exploration missions. Individual sessions addressed nuclear industry, agile manufacturing, security/building monitoring, on-orbit applications, vision and sensing technologies, situated control and low-level control, robotic systems architecture, environmental restoration and waste management, robotic remanufacturing, and healthcare applications

MS FT-2-2 7 Orthogonal polynomials and quadrature: Theory, computation, and applications

Quadrature rules find many applications in science and engineering. Their analysis is a classical area of applied mathematics and continues to attract considerable attention. This seminar brings together speakers with expertise in a large variety of quadrature rules. It is the aim of the seminar to provide an overview of recent developments in the analysis of quadrature rules. The computation of error estimates and novel applications also are described

Generalized averaged Gaussian quadrature and applications

A simple numerical method for constructing the optimal generalized averaged Gaussian quadrature formulas will be presented. These formulas exist in many cases in which real positive GaussKronrod formulas do not exist, and can be used as an adequate alternative in order to estimate the error of a Gaussian rule. We also investigate the conditions under which the optimal averaged Gaussian quadrature formulas and their truncated variants are internal