196,649 research outputs found
Dr. Duane M. Jackson, Morehouse College, July 2011
This video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
The role of docosahexaenoic acid in mediating mitochondrial membrane lipid peroxidation and apoptosis in colonocytes.
Colon cancer is the second leading cause of cancer death in the United States. Epidemiological data indicate that the consumption of dietary fiber and fish/marine products favorably modulate colon tumorigenesis. Docosahexaenoic acid (DHA, 22:6n-3) from fish oil, and butyrate, a fiber fermentation product generated in colon, protect against colon tumorigenesis in part by inducing apoptosis. We have shown that DHA is incorporated into mitochondrial membrane phospholipids, which enhances oxidative stress and mitochondrial membrane potential (MP) dissipation. To elucidate the subcellular origin of oxidation induced by DHA and butyrate exposure, young adult mouse colonocytes (YAMC) were treated with 0200 ??M DHA, linoleic acid (LA, 18:2n-6) or no fatty acid (control) for 72 h with or without 5 mM butyrate for the final 6-24 h. Real time analysis of cellular membrane lipid oxidation, as indicated by oxidation of a lipophilic vital dye, mitochondrial permeability transition (MPT), as characterized by MP dissipation, and cytosolic ROS production, as depicted by hydrophilic ROS reactive fluorophore accumulation, were measured by living cell fluorescence microscopy. After 24 h of butyrate treatment, DHA primed cells showed a 29% increase in lipid oxidation (p<0.01), compared to no butyrate treatment, which could be blocked by a mitochondria targeted antioxidant, MitoQ (p <0.05), whereas LA treatment did not show an effect. In the absence of butyrate, DHA treatment, compared to LA, increased resting MP by 14% (p <0.01). In addition, butyrate-induced MP dissipation was greater (20%) in DHA primed cells as compared to LA (10%). This effect was blocked by pre-incubation with MPT inhibitors, cyclosporin A or bongkrekic acid at 1 ??M. These data suggest an increase in mitochondrial lipid oxidation and the resultant change in MP may contribute to the induction of apoptosis by DHA with butyrate as shown previously
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
Hosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
Following an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
Dietary fish oil and butyrate increase apoptosis and decrease aberrant crypt foci in colon cancer by enhancing histone acetylation and p21waf1/cip1 expression
We have previously shown that dietary fish oil and fiber, particularly the highly-fermentable pectin, are protective against colon cancer in a rat model of carcinogenesis. Therefore, based upon the current body of literature and our previous experimental findings, we hypothesized that one mechanism by which dietary fish oil+pectin suppress the promotion stage of colon cancer is through butyrate, the fermentation product of fiber, targeting (in particular) the p21Waf1/Cip1 gene and, via targeted histone hyperacetylation, inducing its expression. We found that dietary butyrate supplementation increased the concentration of fecal butyrate (mole %) in the distal colon, and that this increase corresponded to an increase in histone H4 acetylation. Similarly, diets supplemented with butyrate increased p21Waf1/Cip1 expression despite azoxymethane (AOM) treatment, which was not seen in non-butyrate supplemented diets. Furthermore, fish oil+butyrate diets resulted in the highest levels of apoptosis and the lowest levels of ACF, while corn oil+butyrate diets resulted in the lowest levels of apoptosis and the highest levels of ACF. Thus, it appears that the protective effect of fish oil+butyrate is due to the unique properties of fish oil, providing an environment in which butyrate��s enhancement of histone acetylation and p21 expression are pro-apoptotic, thereby diminishing pre-neoplastic ACF development
Docosahexaenoic acid differentially modulates plasma membrane targeting and subcellular localization of lipidated proteins in colonocytes
Correct localization of lipidated cytosolic proteins to the plasma membrane (PM) is mediated by interactions between lipid anchors of proteins and cell membranes. Previously, dietary fish oil and its major n-3 polyunsaturated fatty acid (PUFA), docosahexaenoic acid (DHA), have been shown to decrease Ras membrane association, concomitantly reducing rat colon tumor incidence and Ras signaling, compared with corn oil and linoleic acid (LA), a highly prevalent vegetable fat and dietary PUFA in the U.S. diet. In order to explore the potential regulatory role of the cellular lipid environment in PM targeting of lipidated proteins, young adult mouse colon (YAMC) cells were treated with 50 ����M DHA, LA, or oleic acid (OA) 24 h prior to and 36-48 h after transfection with green fluorescent protein (GFP) fusion constructs of various lipidated cytosolic proteins. Relative expression of each GFP fusion protein at the PM and the Golgi in living cells was quantified using z-serial confocal microscopy and digital image processing. DHA differentially altered the subcellular localization of Ras isoforms and Src-related tyrosine kinases in a reversible manner. DHA significantly decreased the PM localization and increased the endomembrane association of H-Ras,
N-Ras, and Lck, which are targeted to the PM via the exocytic pathway, regardless of their functional state. In contrast, the subcellular distribution of K-Ras and Fyn, of which transport is independent of the vesicular transport pathway, was unaffected by DHA. Moreover, DHA selectively inhibited lipidated cytosolic protein targeting since the PM delivery of transmembrane protein cargo was unaffected, indicating that DHA does not alter the bulk flow of secretory vesicular traffic. Overall, the present study presents compelling evidence that select dietary constituents with membrane lipid-modifying properties can differentially modulate subcellular localization of important lipidated signaling proteins depending on their intracellular trafficking route to the PM
Noninvasive detection of colonic biomarkers using fecal messenger RNA
A noninvasive method utilizing feces, containing sloughed colonocytes, as a sensitive technique for detecting diagnostic colonic biomarkers as well as a method for isolating poly A +RNA from feces. The method allows the isolation and quantitation of specific eukarotic mRNAs as candidate biomarkers for colon cancer isolated from feces.U
Summarizing FLARE assay images in colon carcinogenesis
Intestinal tract cancer is one of the more common cancers in the United States. While in some individuals a genetic component causes the cancer, the rate of cancer in the remainder of the population is believed to be affected by diet. Since cancer usually develops slowly, the amount of oxidative damage to DNA can be used as a cancer biomarker. This dissertation examines effective ways of analyzing FLARE assay data, which quantifies oxidative damage. The statistical methods will be implemented on data from a FLARE assay experiment, which examines cells from the duodenum and the colon to see if there is a difference in the risk of cancer due to corn or fish oil diets. Treatments of the oxidizing agent dextran sodium sulfate (DSS), DSS with a recovery period, as well as a control will also be used.
Previous methods presented in the literature examined the FLARE data by summarizing the DNA damage of each cell with a single number, such as the relative tail moment (RTM). Variable skewness is proposed as an alternative measure, and shown to be as effective as the RTM in detecting diet and treatment differences in the standard analysis. The RTM and skewness data is then analyzed using a hierarchical model, with both the skewness and RTM showing diet/treatment differences. Simulated data for this model is also considered, and shows that a Bayes Factor (BF) for higher dimensional models does not follow guidelines presented by Kass and Raftery (1995).
It is hypothesized that more information is obtained by describing the DNA damage functions, instead of summarizing them with a single number. From each function, seven points are picked. First, they are modeled independently, and only diet effects are found. However, when the correlation between points at the cell and rat level is modeled, much stronger diet and treatment differences are shown both in the colon and the duodenum than for any of the previous methods. These results are also easier to interpret and represent graphically, showing that the latter is an effective method of analyzing the FLARE data
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