Acoustic emission testing of composite vessels under sustained loading

Acoustic emissions (AE) generated from Kevlar 49/epoxy composite pressure vessels subjected to sustained load-to-failure tests were studied. Data from two different transducer locations on the vessels were compared. It was found that AE from vessel wall-mounted transducers showed a wide variance from those for identical vessels subjected to the same pressure loading. Emissions from boss-mounted transducers did, however, yield values that were relatively consistent. It appears that the signals from the boss-mounted transducers represent an integrated average of the emissions generated by fibers fracturing during the vessel tests. The AE from boss-mounted transducers were also independent of time for vessel failure. This suggests that a similar number of fiber fractures must occur prior to initiation of vessel failure. These studies indicate a potential for developing an AE test procedure for predicting the residual service life or integrity of composite vessels

Regulation of Peripheral Molecular Clocks in Mammalian Tissues and In Vitro Skeletal Muscle Activation of AMP-Activated Protein Kinase via AICAR

Most organisms possess a common molecular machinery that governs cellular and tissue circadian rhythmicity through a roughly 24-hour transcription-translation feedback loop. It is estimated that up to 15 percent of human genes are influenced by the core clock machinery. It is likely, however, that the metabolic networks affected by the molecular clock differ according to body tissue. Recent evidence suggests that peripheral molecular clocks are governed to a greater extent by energy availability than by light and dark cycles. AMP-activated protein kinase (AMPK) acts as a cellular fuel gauge within the cell and is activated in response to exercise and fasting. AMPK can also be pharmacologically activated by 5-amino-1-β-D-ribofuranosyl-imidazole-4-carboxamide (AICAR). AMPK likely serves as an intermediary between metabolism and the molecular clock due to its activation of the rate-limiting enzyme in Nicotinamide adenine dinucleotide (NAD) biosynthesis, Nicotinamide phosphoribosyltransferase (NAMPT), and its role in PER and CRY degradation. The NAD-dependent histone deacetylase SIRT 1 inhibits the BMAL1-CLOCK complex in a NAMPT-dependent manner.The complex interplay between metabolism and peripheral clocks mediated by AMPK is beginning to be unraveled. AMPK’s tissue-specific influence on the molecular clock in skeletal muscles and other mammalian tissues requires further elucidation as it may provide insight into the etiology and treatment of metabolic disease. [excerpt

Completion of evaluation of manufacturing processes for B/Al composites containing 0.2mm diameter boron fibers

Four fabricators produced a total of 54 B/1100 Al, B/6061 Al, and B/2024 Al panels for evaluation. The 8 ply unidirectional, 45 to 50 volume percent, panels were made using 0.20 mm diameter boron fibers which were obtained from a single supplier. Hot press consolidation was carried out in vacuum except for one set of dry woven tape panels which were hot pressed in air. A single testing contractor conducted nondestructive inspection, metallography, fractography and mechanical property tests. The mechanical property tests included 21 and 260 C tensile tests and 21 C shear tests. Panel quality, as measured by nondestructive evaluation, was generally good as were the 21 C tensile properties. The panels hot pressed in air delaminated in the shear tests. Shear strength values were lower in these panels. But tensile strengths were not affected by the delaminations because of the relation between the tensile loading direction and the delaminations. Composite tensile strength was found to be proportional to the volume percent boron and the aluminum matrix rather than to the tape used or fabrication technique. Suitability of these composites for 260 C service was confirmed by tensile tests

Metal honeycomb to porous wireform substrate diffusion bond evaluation

Two nondestructive techniques were used to evaluate diffusion bond quality between a metal foil honeycomb and porous wireform substrate. The two techniques, cryographics and acousto-ultrasonics, are complementary in revealing variations of bond integrity and quality in shroud segments from an experimental aircraft turbine engine

Electrochemical Sensing of Dopamine using a Dodecylsulfate Doped Polypyrrole Film

A polymer-modified electrode was fabricated by the electropolymerisation of pyrrole from an ethanol solution using sodium dodecylsulfate as a dopant. The modified electrode is a highly sensitive electrochemical sensor for dopamine with a limit of detection measured as 3.8 x 10-8 mol dm-3. The sensor did not sense the common interferant ascorbic acid showing a single redox peak for dopamine in the presence of excess ascorbic acid

Communicating About Evaluation: A Conceptual Model and Case Example

Background: Despite consensus within the evaluation community about what is distinctive about evaluation, confusion among stakeholders and other professions abounds. The evaluation literature describes how those in the social sciences continue to view evaluation as applied social science and part of what they already know how to do, with the implication that no additional training beyond the traditional social sciences is needed. Given the lack of broader understanding of the specialized role of evaluation, the field struggles with how best to communicate about evaluation to stakeholders and other professions. Purpose: This paper addresses the need to clearly communicate what is distinctive about evaluation to stakeholders and other professions by offering a conceptual tool that can be used in dialogue with others. Specifically, we adapt a personnel evaluation framework to map out what is distinctive about what evaluators know and can do. We then compare this map with the knowledge and skill needed in a related profession (i.e., assessment) in order to reveal how the professions differ.  Setting: Not applicable. Intervention: Not applicable. Research Design: Not applicable. Data Collection and Analysis: Not applicable. Findings: We argue that using a conceptual tool such as the one presented in this paper with comparative case examples would clarify for outsiders the distinct work of evaluators. Additionally, we explain how this conceptual tool is flexible and could be extended by evaluation practitioners in a myriad of ways. Keywords: evaluation knowledge; evaluation skill; profession; professionalizatio

Mapping the moral compass : the relationships between in-house lawyers' role, professional orientations, team cultures, organisational pressures, ethical infrastructure and ethical inclination

This is a survey of 400 in-house lawyers working in public, third and commercial sectors. We set out here the findings at the highest level. A number of organisations assisted with the distribution of the survey. This report provides a unique profile of real differences within the in-house community. We examine individual and team orientations to the in-house role; the invocation of professional principles; and ethical infrastructure, ethical pressure and relationships with the employer. We relate these to externally validated indicators of ethical inclination: (i) moral attentiveness (the extent to which people deal with problems as moral problems and the extent to which people identify moral problems); and (ii) moral disengagement (the extent to which people are inclined to morally disengage to behave unethically without feeling distress). It is as rich a picture of what it means to be an ethical inhouse lawyer as has ever been attempted. A more detailed summary and discussion of our findings is found in the final chapter of the main report for those who would like to know more but do not have the appetite or time to read the whole report. Through this research we profile the characteristics of individuals, teams and environments most associated with a stronger or weaker inclination to behave ethically. It is important to emphasise that this mapping of the 'moral compass' of in-house lawyers shows that ethicality is associated with individual and professional notions of the in-house role but also with team orientations and the broader organisational environment. Ethicality is both a systemic and individual phenomenon. We think the systemic lesson is important: there is too much emphasis in legal circles on thinking that ethics is about being the right sort of individual. That kind of thinking is complacent and dangerous. As we show here, individuals, systems and cultures mesh together in meaningful and measurable ways to increase or reduce ethical risk. As numerous corporate scandals have shown, such ethical risk puts individual lawyers at risk of professional misconduct but it also encourages poor quality decision-making for the organisations that employ in-house lawyers: short-termism and sharp practice can lead to catastrophic error

Modeling and simulation of the data communication network at the ASRM Facility

This paper describes the modeling and simulation of the communication network for the NASA Advanced Solid Rocket Motor (ASRM) facility under construction at Yellow Creek near Luka, Mississippi. Manufacturing, testing, and operations at the ASRM site will be performed in different buildings scattered over an 1800 acre site. These buildings are interconnected through a local area network (LAN), which will contain one logical Fiber Distributed Data Interface (FDDI) ring acting as a backbone for the whole complex. The network contains approximately 700 multi-vendor workstations, 22 multi-vendor workcells, and 3 VAX clusters interconnected via Ethernet and FDDI. The different devices produce appreciably different traffic patterns, each pattern will be highly variable, and some patterns will be very bursty. Most traffic is between the VAX clusters and the other devices. Comdisco's Block Oriented Network Simulator (BONeS) has been used for network simulation. The two primary evaluation parameters used to judge the expected network performance are throughput and delay