10,000 publications from this institution
Until the latter part of the 19th century, humans were largely dependent upon contemporaneous biological sources for the production of all organic materials. Plants and animals provided the only sources of fibers, coatings, lubricants, solvents, dyes, waxes, fillers, and insulation, fragrances,
Mental disorders are prevalent and can lead to significant impairment. Some progress has been made toward establishing treatments; however, effect sizes are small to moderate, gains may not persist, and many patients derive no benefit. Our goal is to highlight the potential for empirically supported psychosocial treatments to be improved by incorporating insights from cognitive psychology and research on education. Our central question is: If it were possible to improve memory for the content of sessions of psychosocial treatments, would outcome substantially improve? We leverage insights from scientific knowledge on learning and memory to derive strategies for transdiagnostic and transtreatment cognitive support interventions. These strategies can be applied within and between sessions and to interventions delivered via computer, the Internet, and text message. Additional novel pathways to improving memory include improving sleep, engaging in exercise, and using imagery. Given that memory processes change across the lifespan, services to children and older adults may benefit from different types and amounts of cognitive support.
The recent reversal of capital flows to \n emerging markets has pointed up the continuing relevance of \n the sudden stop problem. This paper analyzes the sudden \n stops in capital flows to emerging markets since 1991. It \n shows that the frequency and duration of sudden stops have \n remained largely unchanged, but that the relative importance \n of different factors in their incidence has changed. In \n particular, global factors appear to have become more \n important relative to country-specific characteristics and \n policies. Sudden stops now tend to affect different parts of \n the world simultaneously rather than bunching regionally. \n Stronger macroeconomic and financial frameworks have allowed \n policy makers to respond more flexibly, but these more \n flexible responses have not guaranteed insulation or \n mitigated the impact of the phenomenon. These findings \n suggest that the challenge of understanding and coping with \n capital-flow volatility is far from fully met.
Not all molecular and nanodevices are useful from an information technology perspective. Such devices are said to be inept in a precise technical sense that can be easily tested from an explicit mathematical criteria to be presented in this two-part tutorial review. Often an inept device can be redesigned into a smart device capable of computing and artificial intelligence by massaging the device's parameters, such as doping, concentration, geometrical profile, chemical moiety, etc., in accordance with the principle of local activity to be articulated in Part II. In particular, designing a smart nanodevice amounts to fine tuning the device parameters into a much smaller niche within the device's locally active parameter region called the edge of chaos where complexity abounds. Molecular and nanodevices will remain novelty toys for nanodevice specialists unless they possess realistic nonlinear circuit models so that future nano circuit designers can simulate their exotic designs as easily and accurately as current CMOS circuit designers. A mathematically consistent theory for modeling nonlinear, high-frequency nanodevices, specially those which exploited exotic tunneling and entanglement quantum mechanical effects, such as Coulomb blockade, quasi-particle dynamics, Kondo resonance, Aharonov-Bohm nonlocal interactions, etc., will require the introduction of a complete family of fundamental circuit elements as model building blocks. They are presented via a doubly periodic table of circuit elements somewhat reminiscent of Mendeleev's periodic table of chemical elements. These fundamental circuit elements can be compactly represented by a loop of four generic species of circuit elements wrapped around the surface of a torus where any higher order element having an arbitrarily high order of frequency dependence can be generated from one of them, modulo the integer 4, ad infinitum. The significance of this four-element torus is that realistic circuit models of all current and future molecular and nanodevices must necessarily build upon an appropriate subset of nonlinear circuit elements begotten from this torus.
A macroporous poly(styrene-co-divinylbenzene) rod has been prepared by a free-radical polymerization of a mixture containing monomers, initiator, and porogenic solvent in the confines of a chromatographic column and used for the first time in the very fast reversed-phase HPLC of proteins. Characterization of the pore structure of the continuous rod by mercury intrusion porosimetry revealed a large volume of pores with a diameter of about 1 micron to pores below 100 nm. Size exclusion chromatography and scanning electron microscopy confirmed the unusual pore size distribution. The presence of large pores make the rod easily permeable to eluents, and therefore, the back pressure of the rod column is modest even at high flow rates. The efficiency of the polymerized column is almost independent of the flow rate. The slope of the line showing capacity factor vs composition of the mobile phase was determined for several proteins, and a gradient for the separation of their mixtures was developed. Excellent separation was achieved even at a high flow rate of 25 mL/min as documented by the resolution data. Tripling the length of the column did not improve the column resolution in protein separation.
AFM was used to investigate the surface morphology and surface modification effects of newly developed segmented polyurethanes and their mixture with phenoxy homopolymer. The polyurethanes were methylene diisocyanate (MDI) and polytetramethyleneoxide (PTMO) based polymer with low surface tension end groups of polydimethysiloxane (PDMS). Two types of surface structures were observed from polyurethanes, a number of holes with a wide range of sizes, presumably due to the large soft segment molecular weight, and fine granular structures on the terraces. The PDMS end groups formed these fine granular structure and made the surface roughness smaller compared to polyurethanes without PDMS. The surface modification effect of polyurethanes was also investigated. The polymer mixtures of polyurethane and phenoxy indicated phase separation of the blends. The surface was composed of two phases, honeycomb polyurethane rich phase and dispersed phenoxy rich phase. The polyurethane rich phase tended to segregate on the surface. The honeycomb phase increased in thickness and area fraction when the polyurethane concentration was increased.
