University of Wisconsin-Madison

About: University of Wisconsin-Madison is a education organization based out in Madison, Wisconsin, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 108707 authors who have published 237594 publications receiving 11883575 citations.

Integrated Catalytic Conversion of γ-Valerolactone to Liquid Alkenes for Transportation Fuels

Abstract: Efficient synthesis of renewable fuels remains a challenging and important line of research. We report a strategy by which aqueous solutions of γ-valerolactone (GVL), produced from biomass-derived carbohydrates, can be converted to liquid alkenes in the molecular weight range appropriate for transportation fuels by an integrated catalytic system that does not require an external source of hydrogen. The GVL feed undergoes decarboxylation at elevated pressures (e.g., 36 bar) over a silica/alumina catalyst to produce a gas stream composed of equimolar amounts of butene and carbon dioxide. This stream is fed directly to an oligomerization reactor containing an acid catalyst (e.g., H ZSM-5, Amberlyst-70), which couples butene monomers to form condensable alkenes with molecular weights that can be targeted for gasoline and/or jet fuel applications. The effluent gaseous stream of CO 2 at elevated pressure can potentially be captured and then treated or sequestered to mitigate greenhouse gas emissions from the process.

Celecoxib for the Prevention of Sporadic Colorectal Adenomas

Abstract: Background Studies showing that drugs that inhibit cyclooxygenase-2 (COX-2) reduce the number of colorectal adenomas in animals and patients with familial adenomatous polyposis suggest that COX-2 inhibitors may also prevent sporadic colorectal neoplasia. Methods We randomly assigned patients who had adenomas removed before study entry to receive placebo (679 patients) or 200 mg (685 patients) or 400 mg (671 patients) of celecoxib twice daily. Randomization was stratified for the use of low-dose aspirin. Follow-up colonoscopies were performed at one and three years after randomization. The occurrence of newly detected colorectal adenomas was compared among the groups with the life-table extension of the Mantel–Haenszel test. Results Follow-up colonoscopies were completed at year 1 in 89.5 percent of randomized patients, and at year 3 in 75.7 percent. The estimated cumulative incidence of the detection of one or more adenomas by year 3 was 60.7 percent for patients receiving placebo, as compared with 43.2 p...

Demographic Diversity in the Boardroom: Mediators of the Board Diversity–Firm Performance Relationship

Abstract: Whereas the majority of research on board diversity explores the direct relationship between racial and gender diversity and firm performance, this paper investigates mediators that explain how board diversity is related to firm performance. Grounded in signalling theory and the behavioural theory of the firm, we suggest that this relationship operates through two mediators: firm reputation and innovation. In a sample of Fortune 500 firms, we find a positive relationship between board racial diversity and both firm reputation and innovation. We find that reputation and innovation both partially mediate the relationship between board racial diversity and firm performance. In addition, we find a positive relationship between board gender diversity and innovation.