Associated and polymerically stabilized dispersions

Our objective is to elucidate the relationships among interparticle forces, microstructure, and rheological properties for concentrated colloidal dispersions and associative polymer solutions. Here we address stable dispersions of spheres bearing grafted polymer chains and solutions of polymer with water soluble backbones modified by the addition of terminal hydrophobes. Non-equilibrium statistical mechanics, combined with treatments of micelles and brushes from the polymer physics literature, offers a means for confirming in detail the mechanisms suggested by recent experiments. © 1999 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87899/2/23_1.pd

How farm people accept new ideas

Some farmers will try any new idea that comes along, while others will accept an idea only after it is proven in their neighborhood. A major concern of agricultural leaders is that of narrowing the time gap between the early and late adoptions of recommended practices. Some new ideas and practices are accepted quickly and with little apparent effort, while others re accepted only after years of effort on the part of agencies and leaders working with rural people.https://lib.dr.iastate.edu/specialreports/1012/thumbnail.jp

Quality by Design: Concepts for ANDAs

Quality by design is an essential part of the modern approach to pharmaceutical quality. There is much confusion among pharmaceutical scientists in generic drug industry about the appropriate element and terminology of quality by design. This paper discusses quality by design for generic drugs and presents a summary of the key terminology. The elements of quality by design are examined and a consistent nomenclature for quality by design, critical quality attribute, critical process parameter, critical material attribute, and control strategy is proposed. Agreement on these key concepts will allow discussion of the application of these concepts to abbreviated new drug applications to progress

FDA Critical Path Initiatives: Opportunities for Generic Drug Development

FDA’s critical path initiative documents have focused on the challenges involved in the development of new drugs. Some of the focus areas identified apply equally to the production of generic drugs. However, there are scientific challenges unique to the development of generic drugs as well. In May 2007, FDA released a document “Critical Path Opportunities for Generic Drugs” that identified some of the specific challenges in the development of generic drugs. The key steps in generic product development are usually characterization of the reference product, design of a pharmaceutically equivalent and bioequivalent product, design of a consistent manufacturing process and conduct of the pivotal bioequivalence study. There are several areas of opportunity where scientific progress could accelerate the development and approval of generic products and expand the range of products for which generic versions are available, while maintaining high standards for quality, safety, and efficacy. These areas include the use of quality by design to develop bioequivalent products, more efficient bioequivalence methods for systemically acting drugs (expansion of BCS waivers, highly variable drugs), and development of new bioequivalence methods for locally acting drugs

Review of the Historical and Present Status of the Lesser Prairie-chicken (Tympanuchus pallidicinctus) in Texas

Historically, the lesser prairie-chicken (Tympanuchus pallidicinctus) occurred in sandy rangeland throughout the northeastern and southwestern (Permian Basin) regions of the Texas Panhandle. Analyses of the historical distribution showed a large reduction in the range of the species in Texas between 1963 and 1980 (78% or 1,070,426 ha), particularly in the southwestern and east-central panhandle, whereas populations in the northeastern Panhandle remained relatively stable. In the northeastern Panhandle, average number of males per lek increased since 1942. In the southwestern Panhandle, average numbers of males per lek decreased dramatically from 1969 to 1981 and from 1985 to 2000, but there was no decline in the northeastern or southwestern panhandle regions from 1990 to 2000. Over the last decade numbers of males per lek in the northeastern Panhandle were 6.6% below the 1942 to 1989 average, but in the southwestern Panhandle they were 54.9% below the 1969 to 1989 average. In the northeastern Panhandle, leks per unit area increased from 1952 to 1986 on the Hemphill County study area and from 1952 to 1974 on the Wheeler County study area. On the Wheeler County study area this variable declined precipitously from 1974 to 1985. The 1997 to 2000 lek per unit area average for the Hemphill County study area was 4.1 % above the J 942 to 1986 average, but was 89.5% below the 1997 to 2000 average in the Wheeler County study area. Small expansions, resulting from increased regional conservation efforts, newly established landowner incentive programs, and partnerships between state and federal resource agencies and private landowners, of range occurred in Bailey, Cochran, Gray, Hemphill, Lipscomb, Terry, and Wheeler counties

How farm people accept new ideas

Some farmers will try any new idea that comes along, while others will accept an idea only after it is proven in their neighborhood. A major concern of agricultural leaders is that of narrowing the time gap between the early and late adoptions of recommended practices. Some new ideas and practices are accepted quickly and with little apparent effort, while others re accepted only after years of effort on the part of agencies and leaders working with rural people.</p