A study to improve the mechanical properties of silicon carbide ribbon fibers

Preliminary deposition studies of SiC ribbon on a carbon ribbon substrate showed that the dominant strength limiting flaws were at the substrate surface. Procedures for making the carbon ribbon substrate from polyimide film were improved, providing lengths up to 450 meters (1,500 ft.) of flat carbon ribbon substrate 1,900 microns (75 mils) wide by 25 microns (1 mil) thick. The flaws on the carbon ribbon were smaller and less frequent than on carbon ribbon used earlier. SiC ribbon made using the improved substrate, including a layer of pyrolytic graphite to reduce further the severity of substrate surface flaws, showed strength levels up to the 2,068 MPa (300 Ksi) target of the program, with average strength levels over 1,700 MPa (250 Ksi) with coefficient of variation as low as 10% for some runs

What Should EDA Fund? Developing a Model for Pre-Assessment of Economic Development Investments

This paper describes the completion of a “comprehensive study of regionalism” that was conducted by a joint team of economists and economic development specialists for the Economic Development Administration (EDA). The project consisted of two main activities: an examination of the factors associated with economic development success and the creation of a practical interactive tool for EDA project assessment and comparison. Findings from surveys, interviews, and project case studies are discussed in terms of their support for a positive relationship between successful economic development efforts and factors such as leadership and private investment. Also, the authors discuss the creation of a quantitative assessment model utilizing well-known approaches such as economic impact multipliers and cluster theory. The primary contribution of this work to the existing body of EDA-focused research and evaluation literature is introducing a means of using standardized scores, also known as z-scores, to compare and assess economic development projects across both industries and regions.regional economic development, economic impact, assessment model, EDA, z-score

An Investigation of User-Led System Design: Rational and Political Perspectives

and organizational factors affecting system implementation (Ives and Olson, in press; RobeyandFarrow, 1982; Fuerstand Cheney, 1982; Lucas 1976).However,littleresearchhas captured the dynamics of user involvement during system development Consequently, we 1mow little about such activities and events as user and designer interaction, top management pressures, political activities, or the role of personnel turnover. To team more about these dynamics, longitudinal research needs to be conducted throughout the system development process. Longitudinal data collection serves two important research objectives: improved measurement validity, and alternative interpretations of events. Events may be described in a more valid manner when data is collected as events occur. This guarantees greater independence of the construct user involvement from the construct system success. In reconstruction studies, respondents\u27 current experience with a system may influence their perceptions of involvement Second, longitudinal study makes it easier to collect alternative interpretations of events in the development process. Activities that are ostensibly undertaken for rational reasons (to deliver a better system) may also serve the political interests of the actors (Robey and Markus, 1984). Longitudinal methods permit respondents\u27 interpretations of these events to be collected as they occur. Thmugh longitudinal research methods, the events of development processes may be described and then interpreted in two ways. One interpretation stresses the rational objectives and methods in development The second interpretation of the same events identifies political themes. These two perspectives coexist and complement one anothe

What Should EDA Fund? Developing a Model for Pre-Assessment of Economic Development Investments

This paper describes the completion of a comprehensive study of regionalism that was conducted by a joint team of economists and economic development specialists for the Economic Development Administration (EDA). The project consisted of two main activities: an examination of the factors associated with economic development success and the creation of a practical interactive tool for EDA project assessment and comparison. Findings from surveys, interviews, and project case studies are discussed in terms of their support for a positive relationship between successful economic development efforts and factors such as leadership and private investment. Also, the authors discuss the creation of a quantitative assessment model utilizing well-known approaches such as economic impact multipliers and cluster theory. The primary contribution of this work to the existing body of EDA-focused research and evaluation literature is introducing a means of using standardized scores, also known as z-scores, to compare and assess economic development projects across both industries and regions

An Acoustic Technique for the Noninvasive in-Situ Measurement of Crystal Size and Solution Concentration

We demonstrated the use of acoustic measurements for tracking potassium dihydrogen phosphate (KDP) crystal growth. Both KDP solution concentration and KDP crystal size can be found by using information derived from acoustic wave propagation in the solution. Acoustic measurements show good correlation to conductivity measurements for KDP solution concentration

Thrombin is a novel regulator of hexokinase activity in mesangial cells

Thrombin is a novel regulator of hexokinase activity in mesangial cells.BackgroundHexokinase (HK) activity is fundamentally important to cellular glucose uptake and metabolism. Phorbol esters increase both HK activity and glucose utilization in cultured mesangial cells via a protein kinase C (PKC)- and extracellular signal-regulated kinases 1 and 2 (ERK1/2)-dependent mechanism. In adult kidneys, increased HK activity has been reported in both glomerular injury and in diabetes, but the mechanisms responsible for these changes are unknown. Thrombin, a known activator of both PKC and ERK1/2, is increased in the settings of renal injury and diabetes. Thus, thrombin may contribute to the observed changes in HK activity in vivo.MethodsThrombin and thrombin receptor agonists were tested for the ability to increase HK activity and glucose metabolism in murine mesangial (SV40 MES 13) cells. ERK1/2 activation was also evaluated in parallel. Thrombin inhibition (hirudins), PKC depletion, Ser-Thr kinase inhibition (H-7), MEK1/2 inhibition (PD98059), pertussis toxin (PTX), and general inhibitors of transcription or translation were then tested for the ability to attenuate these effects.ResultsThrombin (≥0.01 U/mL) mimicked the effect of phorbol esters, increasing HK activity 50% within 12 to 24 hours (P < 0.05). This effect was inhibited by hirudins, mimicked by thrombin receptor agonists, and accompanied by increased Glc utilization. H-7, PD98059, and general inhibitors of transcription or translation—but not PTX—prevented thrombin-induced HK activity at 24 hours. PKC depletion and PD98059 also blocked the associated phosphorylation and activation of ERK1/2.ConclusionsThrombin increases mesangial cell HK activity via a PTX-insensitive mechanism involving thrombin receptor activation, PKC-dependent activation of ERK1/2, and both ongoing gene transcription and de novo protein synthesis. As such, thrombin is a novel regulator of HK activity in mesangial cells and may play a role in coupling renal injury to metabolism

Predicting the safety and efficacy of butter therapy to raise tumour pHe: an integrative modelling study

Background: Clinical positron emission tomography imaging has demonstrated the vast majority of human cancers exhibit significantly increased glucose metabolism when compared with adjacent normal tissue, resulting in an acidic tumour microenvironment. Recent studies demonstrated reducing this acidity through systemic buffers significantly inhibits development and growth of metastases in mouse xenografts.\ud \ud Methods: We apply and extend a previously developed mathematical model of blood and tumour buffering to examine the impact of oral administration of bicarbonate buffer in mice, and the potential impact in humans. We recapitulate the experimentally observed tumour pHe effect of buffer therapy, testing a model prediction in vivo in mice. We parameterise the model to humans to determine the translational safety and efficacy, and predict patient subgroups who could have enhanced treatment response, and the most promising combination or alternative buffer therapies.\ud \ud Results: The model predicts a previously unseen potentially dangerous elevation in blood pHe resulting from bicarbonate therapy in mice, which is confirmed by our in vivo experiments. Simulations predict limited efficacy of bicarbonate, especially in humans with more aggressive cancers. We predict buffer therapy would be most effectual: in elderly patients or individuals with renal impairments; in combination with proton production inhibitors (such as dichloroacetate), renal glomular filtration rate inhibitors (such as non-steroidal anti-inflammatory drugs and angiotensin-converting enzyme inhibitors), or with an alternative buffer reagent possessing an optimal pK of 7.1–7.2.\ud \ud Conclusion: Our mathematical model confirms bicarbonate acts as an effective agent to raise tumour pHe, but potentially induces metabolic alkalosis at the high doses necessary for tumour pHe normalisation. We predict use in elderly patients or in combination with proton production inhibitors or buffers with a pK of 7.1–7.2 is most promising

An Assessment of EDA\u27s Partnership Planning Program

This report examines EDA‘s Partnership Planning Program, which consists of Economic Development Districts (EDDs) and the Comprehensive Economic Development Strategies (CEDS) they are required to create, and provides recommendations as to how the program could be improved to lead effective regional development strategic efforts