3,488 research outputs found
Bacteriophages as Beneficial Regulators of the Mammalian Microbiome
Much of the research on viruses has concentrated on their disease causing ability. The creation model biomatrix theory predicts that viruses play a beneficial role in cells and organisms. In this report we present a new theory which proposes that mammalian phages (bacteriophages), the most abundant organism associated with mammals, guard and regulate growth of the mammalian microbiome. We base this theory on nearly a century of published evidence that demonstrates that phage can insert into the bacterial genome and cover the surface of bacteria. We propose that this “cloaking” of the bacterial cell surface is an elegant mechanism whereby the normal flora bacteria are protected from immune detection and pathogenic bacteria can be directly lysed by the same phage. Additionally, both phage genome integration and cloaking can be used to prevent normal flora bacteria from conversion to a pathogenic state. Further support for the phage cloaking aspect of our theory has been demonstrated in recent studies which show that phage proteins bind specifically to microbial-associated molecular patterns (MAMPs), which are known to be the major ligands that activate the mammalian immune system. Although these phenomena have been documented separately over decades, we postulate for the first time that these functions work together to promote the integrity of the mammalian microbiome
Hydrogen arcjet technology
During the 1960's, a substantial research effort was centered on the development of arcjets for space propulsion applications. The majority of the work was at the 30 kW power level with some work at 1-2 kW. At the end of the research effort, the hydrogen arcjet had demonstrated over 700 hours of life in a continuous endurance test at 30 kW, at a specific impulse over 1000 s, and at an efficiency of 0.41. Another high power design demonstrated 500 h life with an efficiency of over 0.50 at the same specific impulse and power levels. At lower power levels, a life of 150 hours was demonstrated at 2 kW with an efficiency of 0.31 and a specific impulse of 935 s. Lack of a space power source hindered arcjet acceptance and research ceased. Over three decades after the first research began, renewed interest exists for hydrogen arcjets. The new approach includes concurrent development of the power processing technology with the arcjet thruster. Performance data were recently obtained over a power range of 0.3-30 kW. The 2 kW performance has been repeated; however, the present high power performance is lower than that obtained in the 1960's at 30 kW, and lifetimes of present thrusters have not yet been demonstrated. Laboratory power processing units have been developed and operated with hydrogen arcjets for the 0.1 kW to 5 kW power range. A 10 kW power processing unit is under development and has been operated at design power into a resistive load
Transcutaneous measurement of blood velocity profiles and flow
A comprehensive report is presented of the application of a pulsed ultrasound Doppler velocity meter for transcutaneous measurement of time varying velocity, velocity profiles, and instantaneous flow in arteries of anaesthetized dogs. The procedure used to provide direct velocity and flow calibration using the Doppler equation is outlined. Typical transcutaneous recordings obtained from the femoral artery, abdominal aorta, and carotid artery are illustrated. The results compare favourably with data obtained by invasive means such as electromagnetic cuff flowmeters. The possibility of high resolution, non-invasive haemodynamic measurements on dogs is demonstrated and the application to conscious human subjects suggeste
Medium power hydrogen arcjet performance
An experimental investigation was performed to evaluate hydrogen arcjet operating characteristics in the range of 1 to 4 kW. A series of nozzles were operated in modular laboratory thrusters to examine the effects of geometric parameters such as constrictor diameter and nozzle divergence angle. Each nozzle was tested over a range of current and mass flow rates to explore stability and performance. In the range of mass flow rates and power levels tested, specific impulse values between 650 and 1250 sec were obtained at efficiencies between 30 and 40 percent. The performance of the two larger half angle (20, 15 deg) nozzles was similar for each of the two constrictor diameters tested. The nozzles with the smallest half angle (10 deg) were difiicult to operate. A restrike mode of operation was identified and described. Damage in the form of melting was observed in the constrictor region of all the nozzle inserts tested. Arcjet ignition was also difficult in many tests and a glow discharge mode that prevents starting was identified
Iatrogenic enterocutaneous fistula following a misguided surgical procedure in Torit, South Sudan
Groin hernia is common among active people in sub Saharan Africa. It contributes significantly to morbidity and mortality because of its unusual sac content. Various organs can be unexpectedly found in the sac when performing hernia repair surgery. Presence of the caecum in the sac is very uncommon. Enterocutaneous Fistula [ECF] is the worst complication that could occur following groin hernia surgery. We report a rare case of iatrogenic ECF following an incarcerated right inguinal hernia repair done by a traditional healer which caused a cecostomy and subsequent ECF. A 50-year-old lady presented with ECF two weeks after undergoing right inguinal hernia repair. Clinically, and with an aid of abdominal sonogram, a diagnosis of ECF was made. She was successfully treated by caecectomy and primary repair, appendectomy, local debridement of the fistula site and Bassini’s repair of the right inguinal hernia. In cases like this every effort should be made to preserve the organ found in the hernia sac to ensure an uneventful postoperative period. ECF treatment depends on the type, site, and nature of the fistula.
Key words: groin hernia, inguinal hernia, enterocutaneous fistula, caecuminjury
Before You Say Yes: A Planning Guide for Speakers
We need guidelines to help us decide whether to accept invitations to speak, whether to a class on campus or a special interest group outside. As educators and workshop organizers, we could also use suggestions on how to approach potential speakers. This article describes a single-page format that can be used to guide the planning process. Essential elements include contact information, location and organization of the activity, audience, learning goals, expected content, conclusions, and evaluation. Use of this planning sheet can give organization to an often haphazard process of planning, and enhance the potential of achieving the learning goals of a presentation
Report of the panel on volcanology, section 4
Two primary goals are identified as focal to NASA's research efforts in volcanology during the 1990s: to understand the eruption of lavas, gases, and aerosols from volcanoes, the dispersal of these materials on the Earth's surface and through the atmosphere, and the effects of these eruptions on the climate and environment; and to understand the physical processes that lead to the initiation of volcanic activity, that influence the styles of volcanic eruptions, and that dictate the morphology and evolution of volcanic landforms. Strategy and data requirements as well as research efforts are discussed
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Method of identifying inhibitors of glutathione S-transferase (GST) gene expression
Complementary DNA and genomic clones for three variants of GST-.pi. are disclosed. It is demonstrated that certain of these variants are overexpressed in gliomas, thereby indicating an involvement with that form of cancer. This permits the detection and treatment of certain classes of tumors using new compositions such as GST-.pi. genes, oligonucleotides, peptides and antibodies.Board of Regents, University of Texas Syste
Effects of Oil Exploration on Wildlife Resources in Murchison-Semliki Landscape
The fresh water fish in the Albertine lakes and large mammals are under severe threats due to an increase in human population which has resulted in over fishing and poaching. In order to understand the effects of oil exploration on the local communities and natural resources, a total of 374 youths and 51 academic staff from eight (8) Vocational Training Institutions (VTIs) operating in the Albertine region were selected to participate in this study. Additionally, 28 graduate students on a Master of Science in Conservation and Natural Resources Management participated in group discussions focusing on effects of oil exploration on biodiversity conservation. Interviews were held with key informants selected from Uganda Wildlife Authority (UWA), International Oil Companies (IOCs) and the local community members selected from the study districts. Competing land uses that were identified through surveys in the study area included conservation, tourism, agriculture, timber extraction and oil exploration. There was clear evidence of Conservation interests competing with oil industry and human livelihoods. The study has shown that the positive impact of oil and gas exploration includes provision of health services, support for conservation agriculture and providing oil industry skills for the youth in Murchison-Semliki Landscape. Keywords: Agriculture, Albertine Rift, Oil exploration, Wildlife resources, Biodiversity DOI: 10.7176/JEES/14-3-02 Publication date: April 30th 202
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