Spin-coating on nanoscale topography and phase separation of diblock copolymers

CRANN researchers are interested in mathematical modelling of all aspects of the process of spin-coating of diblock copolymers, with the aim of removing expensive trial and error design cycles. Of particular interest is the flow of the polymer during spin-coating, and also during the subsequent annealing process. Also of considerable interest is the chemical process of phase-separation and self-assembly of the diblock copolymer. Existing models in the literature rely heavily on computationally expensive Monte-Carlo simulation methods. The modelling work performed during the study group in summarized in this report. The report is split into four main sections, with discussion and suggestions for experiments in the concluding section. The content of the sections is as follows: Section 0.2: Mathematical modelling of spin-coating onto a flat substrate; no annealing considered. Section 0.3: Modelling of spin-coating onto a substrate with topography (i.e. trenches); no annealing considered. Section 0.4: Flow of polymer during annealing. Section 0.5: Models for self-assembly of polymers into nanostructures. Sections 0.2 to 0.4 are focussed on the fluid flow problems for the polymer, and go some way to providing useful answers to Problem 1. On the other hand, Problem 2 was found to be extremely challenging, and the efforts described in section 0.5 represent only a relatively modest impact on this problem

Summary of a Crew-Centered Flight Deck Design Philosophy for High-Speed Civil Transport (HSCT) Aircraft

Past flight deck design practices used within the U.S. commercial transport aircraft industry have been highly successful in producing safe and efficient aircraft. However, recent advances in automation have changed the way pilots operate aircraft, and these changes make it necessary to reconsider overall flight deck design. Automated systems have become more complex and numerous, and often their inner functioning is partially or fully opaque to the flight crew. Recent accidents and incidents involving autoflight system mode awareness Dornheim, 1995) are an example. This increase in complexity raises pilot concerns about the trustworthiness of automation, and makes it difficult for the crew to be aware of all the intricacies of operation that may impact safe flight. While pilots remain ultimately responsible for mission success, performance of flight deck tasks has been more widely distributed across human and automated resources. Advances in sensor and data integration technologies now make far more information available than may be prudent to present to the flight crew

An Analysis of the CAP Reform

The Treaty of Rome, which established the European Economic Community in 1957, defined the objectives of the Common Agricultural Policy (CAP). These objectives, contained in Article 39, follow: 1) Increase agricultural productivity by promoting technical progress and by ensuring rational development of agricultural production and optimum use of the production factors, particularly labor. 2) Ensure a fair standard of living for the agricultural community, in particular by increasing the individual earning of the persons engaged in agriculture. 3) Stabilize markets. 4) Assure the availability of supplies. 5) Ensure that supplies reach consumers at reasonable prices. The objectives of the CAP have been met, mostly through price policies that traditionally have been tied to production. The result of these policies is that production of many agricultural commodities has increased beyond levels necessary to meet CAP objectives and excess supplies have accumulated, been exported with subsidies, or both, at great expense to the European Community

Body Condition of Endangered Humpback Chub in Relation to Temperature and Discharge in the Lower Colorado River

Determining the population status of endangered Humpback Chub Gila cypha is a major component of the adaptive management program designed to inform operation of Glen Canyon Dam upstream from Grand Canyon, Arizona. In recent decades, resource managers have identified a portfolio of management actions (with intermittent implementation) to promote population recovery of Humpback Chub, including nonnative fish removal, changes in water release volumes and discharge ramping schedules, and reductions in hydropower peaking operations. The Humpback Chub population in Grand Canyon has increased over this same period, causal factors for which are unclear. We took advantage of unusual hydrology in the Colorado River basin in 2011 to assess trends in juvenile Humpback Chub length–weight relationships and condition in the Colorado River below Glen Canyon Dam as well as in the unregulated Little Colorado River. Within each river, we observed higher length–weight b-parameter estimates (exponent of the standard power equation) at higher water temperatures. We also found higher slope estimates for the length–weight relationship at higher temperatures in the Little Colorado River. Slope estimates were more variable in the Colorado River, where mean water temperatures were more uniform. The next step is to examine whether Humpback Chub length–weight relationships influence population metrics such as abundance or survival. If these relationships exist, then monitoring condition in juvenile Humpback Chub would provide a quick and low-cost technique for assessing population response to planned management experiments or changing environmental conditions

Implications of a GATT Agreement for World Commodity Markets, 1993-98: An Analysis of the Dunkel Text on Agriculture

The Food and Agricultural Policy Research Institute (FAPRI) received a request in mid-February to analyze the proposed changes to agriculture and agricultural trade made by Arthur Dunkel. These changes essentially fall into three areas. 1) Export Competition. Subsidies are subject to reduction in two ways. Expenditures are to be reduced by 36 percent and quantities exported with the benefit of subsidies are to be reduced by 24 percent from 1986-90 average levels. 2) Internal Support. Using a world reference price based on the 1986-88 average levels, internal supports as measured by an aggregate measure of support (AMS) are to be reduced by 20 percent from 1986 levels. Credit will be given for support reductions made since 1986. 3) Market Access. Import restrictions are to be converted to tariffs and reduced across the board by a simple average of 36 percent. Tariffs on individual commodities are to be reduced by at least 15 percent. Where import barriers are in place, either minimum access of 3 percent of domestic consumption in 1993, rising to 5 percent in 1999, or minimum access of 1986-88 average import levels is to be provided, whichever is greater

Enterococcus faecalis tropism for the kidneys in the urinary tract of C57BL/6J mice

Enterococcus faecalis is a gram-positive bacterium that can cause a variety of nosocomial infections of which urinary tract infections are the most common. These infections can be exceptionally difficult to treat because of drug resistance of many E. faecalis isolates. Despite their troublesome nature, little is known about the host or bacterial factors necessary for E. faecalis to cause disease in the urinary tract. Using a mouse model of urinary tract infection, we have shown that E. faecalis is capable of persisting in the kidneys of mice for at least 2 weeks. In contrast, bacterial titers from the bladders of the same mice were inconsistent and tended to be much lower than those recovered from the kidney. This preference for the kidney over the bladder is also observed in other clinical E. faecalis strains. Histologic examination of bladder and kidney tissues demon-strated that E. faecalis induced an inflammatory response in the kidney but not in the bladder. This inflam-matory response was TLR2 independent and did not induce inflammatory markers typically associated with uropathogenic Escherichia coli. Using a competition assay, we demonstrated that a pyelonephritis clinical isolate had a growth advantage over a laboratory strain of E. faecalis in the kidneys but not in the bladders of mice. Taken together, these results demonstrate that E. faecalis has tropism for the kidneys in the urinary tracts of mice and that this system can be used to study factors involved in the pathogenesis of urinary tract infections

Implications of a GATT Agreement for World Commodity Markets, 1991-2000

A dynamic multicountry, multicommodity model is used to evaluate the impact of a moderate General Agreement on Tariffs and Trade (GATT) agreement. The terms of this agreement are as follows. 1) Export subsidy quantities (using annual and price wedges) are reduced by 50 percent from the 1986-88 average by 1996. 2) Import restrictions are tariffed and reduced by 33 percent form the 1986-88 average by 1996 (tariffs are measured by using an annual price wedge approach). 3) Internal supports, as measured by the aggregate measure of support (AMS) are reduced by 33 percent from the 1986-88 average by 1996 (fixed reference prices are used). The results indicate that the U.S. producers would benefit substantially from the agreement because the United States has made or will have made many of the cuts required by this moderate agreement. The results also indicate that the choice of the base year is a very important variable influencing the relative benefits and losses under any likely GATT agreement