729 research outputs found
Design and process development of an integrated phosphor field emission device
An Integrated Phosphor Field Emission Device (IPFED) has been fabricated at the Rochester Institute of Technology for the purpose of developing a new, flat panel display technology. The device incorporates a new, cathodoluminescent, thin film phosphor (Ta2Zn308) developed at RIT as an anode. A cathode and control gate, both consisting of a thin layer of molybdenum are also included in the device. Electrons are tunneled from the cathode via Fowler-Nordheim tunneling to energetically strike the phosphor anode. The anode then produces light, via cathodoluminescence, which the human eye can detect. Standard semiconductor processes were utilized in the fabrication of the device. These processes include; sputtering of Zinc Oxide, tantalum, molybdenum, and quartz, deposition of chemically vapor deposited (CVD) oxide, reactive ion etching of tantalum, molybdenum, and silicon dioxide using CHF3/He, CF4/H2, or SF6 plasmas, using a G-line stepper and diazonaphthoquinone (DNQ) novolac resin resists to pattern the aforementioned materials, and utilizing a Rapid Thermal Processor (RTP). The device can be scaled from ultra high resolution (10 jim pitch or less) to standard SVGA resolution (0.28mm pitch). Bright (no way to quantify) pixels have been observed at 200nA of current at 100V of acceleration energy. The control gate which was built into the structure does not function as designed due to shorting problems between the control gate and cathode. A process for the vacuum encapsulation of the devices has also been developed. This process does not require any special alignment of a separate faceplate. Many of the known problems with other field emissive displays have been circumvented by this new design
The use and development of geographical information systems (GIS) and spatial modelling for educational planning
Since the passing of the 1988 Education Reform Act British education, particularly at a secondary level, has been transformed. The changes enacted in this and subsequent
legislation have opened up state-provided education to a market-oriented system which is led more by the preferences of parents than the dictation of local or national planners.
This means that local authorities and other providers of education have been left in a situation where they are relatively powerless to provide adequate schooling in a
proactive manner. It is also the case that there is a danger of a 'two-tier' education system developing whereby the better-informed middle classes are served by high achieving schools and less advantaged pupils are left to fill inner city 'sink' schools which cannot provide them with the same educational chances due to lower resource
levels. This thesis presents a feasibility study of a variety of techniques drawn from academic and applied geography which can be utilised by such planners in order to
better target the resources available to them and improve their reactions to the vagaries of the market.
These tools concentrate on geographical information systems (GIS) and spatial modelling techniques. Although both of these sets of techniques have for many years been applied in other areas, including within local Government, they have yet to permeate to a decision-making level in education planning. Thus the time is ripe for their wider dissemination and application in this area. Several examples of the possible uses of GIS are given, using real data for Leeds schools and pupils. Various types of spatial model are described and the most appropriate are calibrated and applied using the same Leeds data.
The thesis concludes that the benefits of modelling techniques for planners at all scales, from individual schools to national Government, could be enormous. Through the application of these tools planners will be better placed to provide an education service which caters for all pupils within it. However, there are caveats regarding the
requirement for further research into improving model performance and ensuring that output is sufficiently user-friendly
Total cross sections for the production of positive ions and free electrons by helium ions in gaseous targets
Ph.D.David W. Marti
Milk whey protein concentration and mRNA associated with β-lactoglobulin phenotype
Two common genetic variants of β-lactoglobulin (β-lg), A and B, exist as co- dominant alleles in dairy cattle (Aschaffenburg, 1968). Numerous studies have shown that cows homozygous for β-lg A have more β-lg and less α-lactalbumin (α-la) and casein in their milk than cows expressing only the B variant of β-lg (Ng-Kwai-Hang et al. 1987; Graml et al. 1989; Hill, 1993; Hill et al. 1995, 1997). These differences have a significant impact on the processing characteristics of the milk. For instance, the moisture-adjusted yield of Cheddar cheese is up to 10% higher using milk from cows of the β-lg BB phenotype compared with milk from cows expressing only the A variant (Hill et al. 1997). All these studies, however, describe compositional differences associated with β-lg phenotype in established lactation only. No information is available on the first few weeks of lactation, when there are marked changes in the concentrations of β-lg and α-la (Pérez et al. 1990)
Blockchains, Property Rights and Health Technology Assessment in the Pharmaceutical and Device(s) Industries
Ongoing concerns with the security of health information, both from the perspective of the individual patient as well as health systems has led to increased attention being given to the potential role of blockchain technology in the secure storage of health information through encryption, the integration of diverse health record systems and the vesting of property and access rights to health data in the patient. While the security offered by blockchain technology has long been recognized in the finance sector with the emergence of a range of cryptocurrencies as a medium of exchange and store of value, demonstrating the value of blockchain technology in health management and health technology assessment has yet to be achieved. In this commentary, a number of questions are raised as to the potential value offered by blockchain technology as a complement to existing electronic medical record systems. Chief among these are: (i) the allocation of property rights as a necessary precondition for blockchain uptake; (ii) access and incentives for active as opposed to passive blockchain membership; (iii) monetization of blockchain access; (iv) capturing data from within the blockchain and the possibility of value added data; (v) the potential for blockchain platforms in formulary evaluations; (vi) the blockchain as a managed market for health data; and (vii) the role of intermediation in blockchain management.
Article Type: Commentar
Blockchains, Formulary Evaluations and Health Technology Assessment
Blockchains have the potential, if appropriately implemented and managed, of contributing to a fundamental change in the application of techniques of health technology assessment in formulary decision making. Rather than continuing to rely on claims made by manufacturers that are non-evaluable, the introduction of blockchains as adjunct to the electronic medical record, meet an unmet medical need in enabling a platform for the real time assessment of claims. Rather than focusing the case for their product on lifetime cost-per-QALY models, which have no chance of ever being validated, the blockchain platform offers a low cost opportunity for claims evaluation. Manufacturers would be required to abandon the construction of imaginary cost-per-QALY worlds to support claims for pricing and formulary trier position, in favor of claims that can be evaluated and reported back to formulary committees in a short yet meaningful time horizon. Manufacturers would present a claims assessment protocol as part of the formulary submission package. If agreed with the formulary committee, the protocol would be implemented and managed through the patient blockchain membership. Claims would be monitored and evaluated in real time with a final report to the formulary committee in a matter of months. Lifetime imaginary claims for cost-per-QALY, set alongside willingness-to-pay thresholds, would be a thing of the past. Pricing decisions and formulary placement would reflect a robust evidence base and not just extrapolations from pivotal clinical trials.
Article Type: Commentar
If You Build it Will They Come? Patients, Providers and Blockchains in Health Technology Assessment
It is an open question as to whether blockchains can become an integral part of health care management in the US. On the one hand, there are the advocates of blockchains who see them as empowering patients to capture property rights to their medical records in a secure, encrypted, and portable form. On the other hand, there are blockchain critics that see the opportunities offered in health care as little different from those offered in other industries, viewing a blockchain structure as one that may reduce administrative and transaction costs, with little thought given to the potential of blockchain platforms to support a range of health technology assessment activities. While previous commentaries have pointed to this potential, the obstacles offered by the absence of clearly defined property rights and the absence of a market for DNA profiles have not been explored. The case put forward here is that any expectation that a blockchain as a ‘one-stop-shop’ for the interrogation of personal health records alone is unlikely to succeed. Apart from property rights effectively blocking this business model the blockchain vendor should consider targeted value added activities. At best, only a subset of records has the possibility of being transferred, with ongoing concerns regarding their quality and scope. This does not mean that the blockchain software model should be rejected. Far from it. The blockchain as a health technology assessment platform has the potential to support added value activities which not only improve the process of care and reduce costs and improve efficiencies, but also provide an ideal framework for property rights assignment. This opens the door to incentives and the monetization of value added health data by patients and providers, capturing rents that are at the moment expropriated by third parties. Critical issues are not only property rights and creation of a market place, but the ability to link and incentivize patients and their providers to support active blockchains to generate value added.
Article Type: Commentar
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