Ceramic regenerator systems development program

The DOE/NASA Ceramic Regenerator Design and Reliability Program aims to develop ceramic regenerator cores that can be used in passenger car and industrial/truck gas turbine engines. The major cause of failure of early gas turbine regenerators was found to be chemical attack of the ceramic material. Improved materials and design concepts aimed at reducing or eliminating chemical attack were placed on durability test in Ford 707 industrial gas turbine engines late in 1974. Results of 53,065 hours of turbine engine durability testing are described. Two materials, aluminum silicate and magnesium aluminum silicate, show promise. Five aluminum silicate cores attained the durability objective of 10,000 hours at 800 C (1472 F). Another aluminum silicate core shows minimal evidence of chemical attack after 8071 hours at 982 C (1800 F). Results obtained in ceramic material screening tests, aerothermodynamic performance tests, stress analysis, cost studies, and material specifications are included

Prospectus, October 21, 1971

GOOD ELECTION MARRED BY LIGHT TURN-OUT; Lieutenant Governor Simon Speaks To College Democrats of Illinois; Arc Triangle; Seed For Thought; Bull Sheet: Key Notes, S.W.A.M.P. Conducts Membership Drive, I.O.C. Special, Library Hours For Veterans Day Weekend, Gymnastics, Ski Club, Phi Beta Lambda, Draft Deferments For Freshman; Student Government In Action; News Briefshttps://spark.parkland.edu/prospectus_1971/1003/thumbnail.jp

Using virtual worlds for role play simulation in child psychiatry: an evaluation study

Aims and method: To develop and evaluate a novel teaching session on clinical assessment using role play simulation. Teaching and research sessions occurred sequentially in computer laboratories. Ten medical students were divided into two online small-group teaching sessions. Students role-played as clinician avatars and the teacher played a suicidal adolescent avatar. Questionnaire and focus-group methodology evaluated participants’ attitudes to the learning experience. Quantitative data were analysed using SPSS, qualitative data through nominal-group and thematic analyses. Results: Participants reported improvements in psychiatric skills/knowledge, expressing less anxiety and more enjoyment than role-playing face to face. Simulator fidelity correlated positively with utility. Some participants expressed concern about added value over other learning methods and non-verbal communication. Clinical implications: The study shows that virtual worlds can successfully host role play simulation, valued by students as a useful learning method. The potential for distance learning would allow delivery irrespective of geographical distance and boundaries

Catching Kordbolbok: From Frog Survey to Closing the Gap in Arnhem Land

This working paper introduces the first frog survey of the Arnhem Plateau, as far as we know, which was conducted by the Warddeken Indigenous Rangers and a western scientist employed by CAEPR. The survey methodology and outcomes are presented in conjunction with some comment on the socioeconomic benefits of such surveys in remote outstations of the Northern Territory. Thirteen native frog species known to western science were found, including one species that as far as we know is previously undescribed—as well as the exotic cane toad (Bufo marinus). This exercise highlighted the significant role already played by traditional owners in the management of Indigenous-owned Arnhem Land. A greater monitoring role—for example, through frog surveys—could be pursued given the right tools and training

Inhibition of Interleukin-1-Induced Effects in Synoviocytes Transduced with the Human IL-1 Receptor Antagonist cDNA Using an Adenoviral Vector

Overview summary Adenovirus-mediated gene transfer into the cells of the synovial membrane may provide a means to deliver therapeutically active proteins for the local modification of the immune response in inflammatory arthropathies. In this study, we infected type B human synoviocytes in vitro and rabbit synovial lining membrane in vivo with a recombinant human adenovirus containing the cDNA for the human interleukin-1 receptor antagonist protein (IL-1ra). Expression of human IL-1ra was observed both in the transduced synoviocytes in vitro and in the microenvironment of the transduced rabbit synovial membrane in vivo, and the functional activity of the transgenic IL-1ra was suggested by in vitro inhibition of interleukin-1 (IL-1)-induced prostaglandin E2 (PGE2) production and by in vivo inhibition of IL-1-induced glycosaminoglycan (GAG) degradation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63124/1/hum.1995.6.3-307.pd

Spaces of novelty: Can universities play a catalytic role in less developed regions?

Over the past few decades, universities have been asked to become ever more involved in the development of their regions and countries, through knowledge dissemination, contribution to policy debates or even by becoming leaders in stakeholder coalitions. However, as has been often pointed out, for universities to have an impact on regional fortunes it is necessary to have an appropriate innovation ecosystem, which is often lacking in less developed regions. We approach this issue by discussing the three interrelated dimensions of knowledge supply, demand, and translational activities, through two case studies of university–business engagement in Wales. We also distinguish between narrow forms of engagement, based strictly on the commercialisation of knowledge, and contrast them with broader forms of engagement. Finally, we discuss the practical and normative challenges associated with these interactions, such as the danger of appropriation of public resources by private organisations

Salmonella Pathogenicity Island 2 Is Expressed Prior to Penetrating the Intestine

Salmonella enterica serovar Typhimurium is a facultative intracellular pathogen that causes disease in mice that resembles human typhoid. Typhoid pathogenesis consists of distinct phases in the intestine and a subsequent systemic phase in which bacteria replicate in macrophages of the liver and spleen. The type III secretion system encoded by Salmonella pathogenicity island 2 (SPI-2) is a major virulence factor contributing to the systemic phase of typhoid pathogenesis. Understanding how pathogens regulate virulence mechanisms in response to the environment, including different host tissues, is key to our understanding of pathogenesis. A recombinase-based in vivo expression technology system was developed to assess SPI-2 expression during murine typhoid. SPI-2 expression was detectable at very early times in bacteria that were resident in the lumen of the ileum and was independent of active bacterial invasion of the epithelium. We also provide direct evidence for the regulation of SPI-2 by the Salmonella transcription factors ompR and ssrB in vivo. Together these results demonstrate that SPI-2 expression precedes penetration of the intestinal epithelium. This induction of expression precedes any documented SPI-2-dependent phases of typhoid and may be involved in preparing Salmonella to successfully resist the antimicrobial environment encountered within macrophages

The key role of nitric oxide in hypoxia: hypoxic vasodilation and energy supply-demand matching

Significance: a mismatch between energy supply and demand induces tissue hypoxia with the potential to cause cell death and organ failure. Whenever arterial oxygen concentration is reduced, increases in blood flow - 'hypoxic vasodilation' - occur in an attempt to restore oxygen supply. Nitric oxide is a major signalling and effector molecule mediating the body's response to hypoxia, given its unique characteristics of vasodilation (improving blood flow and oxygen supply) and modulation of energetic metabolism (reducing oxygen consumption and promoting utilization of alternative pathways). Recent advances: this review covers the role of oxygen in metabolism and responses to hypoxia, the hemodynamic and metabolic effects of nitric oxide, and mechanisms underlying the involvement of nitric oxide in hypoxic vasodilation. Recent insights into nitric oxide metabolism will be discussed, including the role for dietary intake of nitrate, endogenous nitrite reductases, and release of nitric oxide from storage pools. The processes through which nitric oxide levels are elevated during hypoxia are presented, namely (i) increased synthesis from nitric oxide synthases, increased reduction of nitrite to nitric oxide by heme- or pterin-based enzymes and increased release from nitric oxide stores, and (ii) reduced deactivation by mitochondrial cytochrome c oxidase. Critical issues: several reviews covered modulation of energetic metabolism by nitric oxide, while here we highlight the crucial role NO plays in achieving cardiocirculatory homeostasis during acute hypoxia through both vasodilation and metabolic suppression Future directions: we identify a key position for nitric oxide in the body's adaptation to an acute energy supply-demand mismatc

Selenoprotein P Influences Colitis-Induced Tumorigenesis by Mediating Stemness and Oxidative Damage.

Patients with inflammatory bowel disease are at increased risk for colon cancer due to augmented oxidative stress. These patients also have compromised antioxidant defenses as the result of nutritional deficiencies. The micronutrient selenium is essential for selenoprotein production and is transported from the liver to target tissues via selenoprotein P (SEPP1). Target tissues also produce SEPP1, which is thought to possess an endogenous antioxidant function. Here, we have shown that mice with Sepp1 haploinsufficiency or mutations that disrupt either the selenium transport or the enzymatic domain of SEPP1 exhibit increased colitis-associated carcinogenesis as the result of increased genomic instability and promotion of a protumorigenic microenvironment. Reduced SEPP1 function markedly increased M2-polarized macrophages, indicating a role for SEPP1 in macrophage polarization and immune function. Furthermore, compared with partial loss, complete loss of SEPP1 substantially reduced tumor burden, in part due to increased apoptosis. Using intestinal organoid cultures, we found that, compared with those from WT animals, Sepp1-null cultures display increased stem cell characteristics that are coupled with increased ROS production, DNA damage, proliferation, decreased cell survival, and modulation of WNT signaling in response to H2O2-mediated oxidative stress. Together, these data demonstrate that SEPP1 influences inflammatory tumorigenesis by affecting genomic stability, the inflammatory microenvironment, and epithelial stem cell functions