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Life Sciences

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Iowa State University

2001

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Liquid Dairy Waste Transport And Land Application Cost Comparisons Considering Herd Size, Transport Distance, And Nitrogen Versus Phosphorus Application Rates, Robert T. Burns, A. S. Daugherty, T. L. Cross, D. Raj Raman, G. F. Grandle Jul 2001

Liquid Dairy Waste Transport And Land Application Cost Comparisons Considering Herd Size, Transport Distance, And Nitrogen Versus Phosphorus Application Rates, Robert T. Burns, A. S. Daugherty, T. L. Cross, D. Raj Raman, G. F. Grandle

D. Raj Raman

This study provides cost comparisons for the transport and application of dairy waste slurries based on both phosphorus and nitrogen application rates. Estimated cost comparisons are made for several commonly used systems for dairy waste transport and application. Five dairy sizes ranging from 50 to 2,000 cows using 13 transport and application systems were evaluated. For each dairy size, the costs associated with the transport and application system combinations were determined for transport distances of 0.5, 1.5, and 4.5 miles for both nitrogen and phosphorus-based application rates. Total annual system cost, cost per acre, cost per cow, and manure value …

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Incidence Of Escherichia Coli O157:H7, Listeria Monocytogenes , And Salmonella Species On A Tennessee Dairy Farm, T. L. Ervin, R. E. Yoder, F. A. Draughon, Robert T. Burns, D. Raj Raman Jul 2001

Incidence Of Escherichia Coli O157:H7, Listeria Monocytogenes , And Salmonella Species On A Tennessee Dairy Farm, T. L. Ervin, R. E. Yoder, F. A. Draughon, Robert T. Burns, D. Raj Raman

D. Raj Raman

In response to public awareness of foodborne pathogens due to recent outbreaks of illness, a study was conducted on the incidence of Escherichia coli O157:H7, Listeria monocytogenes , and Salmonella species on a dairy farm in middle Tennessee. Sampling locations included water samples from up- and down-stream in a creek running through the farm, free stall bedding, silage, separator liquids, separator solids, pumped liquid from a holding pond, feed, and bulk tank milk. Three samples were taken monthly at each location for 12 months. These samples were tested to determine the incidence of pathogens on the dairy farm and to …

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Β-Lactoglobulin Molten Globule Induced By High Pressure, Jian Yang, A. Keith Dunker, Joseph R. Powers, Stephanie Clark, Barry G. Swanson Jun 2001

Β-Lactoglobulin Molten Globule Induced By High Pressure, Jian Yang, A. Keith Dunker, Joseph R. Powers, Stephanie Clark, Barry G. Swanson

Stephanie Clark

Beta-lactoglobulin (beta-LG) was treated with high hydrostatic pressure (HHP) at 600 MPa and 50 degrees C for selected times as long as 64 min. The intrinsic tryptophan fluorescence of beta-LG indicated that HHP treatment conditions induced a conformational change. HHP treatment conditions also promote a 3-fold increase in the extrinsic fluorescence of 1-anilinonaphthalene-8-sulfonate and a 2.6-fold decrease for cis-paraneric acid, suggesting an increase in accessible aromatic hydrophobicity and a decrease in aliphatic hydrophobicity. Far-ultraviolet circular dichroism (CD) spectra reveal that the secondary structure of beta-LG converts from native beta-sheets to non-native alpha-helices following HHP treatment, whereas near-ultraviolet CD spectra reveal …

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Preliminary Exercise Identity Scale (Eis) Norms For Three Adult Samples, Dean F. Anderson, Charles M. Cychosz, Warren D. Franke Jan 2001

Preliminary Exercise Identity Scale (Eis) Norms For Three Adult Samples, Dean F. Anderson, Charles M. Cychosz, Warren D. Franke

Warren D Franke

Sociological traditions suggest that role identities serve to give meaning and impor­tance to past behavior as well as provide direction for future behavior. The Exercise Identity Scale (EIS) was developed to measure the extent to which exercise contributes to an individual's role-identity. This investigation examined age norms on the EIS. Data were collected from three populations including a convenience sample of 203 college students enrolled in three elective health-studies courses (92% Caucasian and 63% female), 441 of 531 (83%) law enforcement employees in a state department concerned with public safety (98% Caucasian and 96% male), and 1253 of 4000 (32%) …

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Phylogeographic Analysis Of The Threatened And Endangered Superconglutinate-Producing Mussels Of The Genus Lampsilis (Bivalvia: Unionidae), Kevin J. Roe, Charles Lydeard, Paul D. Hartfield Jan 2001

Phylogeographic Analysis Of The Threatened And Endangered Superconglutinate-Producing Mussels Of The Genus Lampsilis (Bivalvia: Unionidae), Kevin J. Roe, Charles Lydeard, Paul D. Hartfield

Kevin J. Roe

Several species of freshwater unionid mussels in the genus Lampsilis exhibit a remarkable reproductive strategy. Female mussels of these species enclose their larvae in a minnow-like lure, called a ‘superconglutinate’, to attract piscivorous fishes. When a fish attempts to ingest the superconglutinate the lure ruptures and the larvae are released to parasitize the fish. Of the four species of mussel which exhibit this strategy and are endemic to the Gulf Coast drainages of the southeastern United States, three are protected under the Endangered Species Act, and one is recognized as imperilled. Phylogenetic analysis of nucleotide sequences of the mitochondrial 16S …

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Effects Of Elevated Co2 On The Response Of Phleum Pratense And Poa Pratensis To Aboveground Defoliation And Root-Feeding Nematodes, Brian J. Wilsey Jan 2001

Effects Of Elevated Co2 On The Response Of Phleum Pratense And Poa Pratensis To Aboveground Defoliation And Root-Feeding Nematodes, Brian J. Wilsey

Brian J. Wilsey

Because of the importance of herbivory in many herbaceous plant–dominated ecosystems, it will be important to determine whether interactions exist between herbivory and CO2 enrichment if we are to understand better how ecosystems will respond to global change. In an experiment with the C3 grasses Poa pratensis and Phleum pratense, plants were grown together under ambient (360 ppm) and elevated (650 ppm) CO2, with and without aboveground defoliation, and with or without additions of the root-feeding nematode Pratylenchus penetrans. The objective was to determine whether herbivory would interact with CO2 enrichment in determining biomass responses or whether these factors were …

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Determination Of 17ss-Estradiol Concentrations In Runoff From Plots Receiving Dairy Manure, A. R. Dyer, D. Raj Raman, M. D. Mullen, Robert T. Burns, Lara B. Moody, A. C. Layton Jan 2001

Determination Of 17ss-Estradiol Concentrations In Runoff From Plots Receiving Dairy Manure, A. R. Dyer, D. Raj Raman, M. D. Mullen, Robert T. Burns, Lara B. Moody, A. C. Layton

D. Raj Raman

Because of growing concern about estrogenic compounds in animal wastes, the objective of this research was to measure 17 ß -estradiol concentrations in runoff from plots fertilized with liquid dairy waste. Nine plots were established at The University of Tennessee Dairy Experiment Station located at Lewisburg, Tennessee, and dairy manure was applied to six of the nine plots. Three of the plots received manure at a rate sufficient to meet the nitrogen (N) requirement for winter wheat; three received manure at a rate sufficient to meet the phosphorus (P) requirement for winter wheat, and three received no manure. Runoff samples …

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Enhancing Dairy Lagoon Performance With High-Rate Anaerobic Digesters, Gary L. Hawkins, D. Raj Raman, Robert T. Burns, Ronald E. Yoder, Tim L. Cross Jan 2001

Enhancing Dairy Lagoon Performance With High-Rate Anaerobic Digesters, Gary L. Hawkins, D. Raj Raman, Robert T. Burns, Ronald E. Yoder, Tim L. Cross

D. Raj Raman

In a two–stage study, the possibility of using high–rate anaerobic digesters to enhance the performance of dairy lagoons was explored. Four anaerobic sequencing batch reactors (ASBR) and four downflow anaerobic filters (DFAF) were tested, with two of each type operated at 25C, and the other two at 35C. The first stage of the experiment explored using the high–rate digesters on liquid effluent from a screw–press treating dairy manure slurry. The first–stage experiment demonstrated that settling processes, rather than biodegradation, accounted for most of the organic matter reduction in both reactor types, when operated at a 0.5–d hydraulic retention time. Specifically, …

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Degradation Of Estrogens In Dairy Waste Solids: Effects Of Acidification And Temperature, D. Raj Raman, Alice C. Layton, Lara B. Moody, James P. Easter, Gary S. Sayler, Robert T. Burns Jan 2001

Degradation Of Estrogens In Dairy Waste Solids: Effects Of Acidification And Temperature, D. Raj Raman, Alice C. Layton, Lara B. Moody, James P. Easter, Gary S. Sayler, Robert T. Burns

D. Raj Raman

Manure–borne estrogens are increasingly recognized as a potential ecological hazard. However, sample–handling protocols for these compounds are not clearly delineated in the literature, nor are comparisons between assays for estrogens. A study was conducted to explore the degradation of estrogen in separated dairy manure waste solids (press cake), using three popular assay types. Estrogens were measured by enzyme–linked immunosorbent assay (ELISA), gas–chromatography mass–spectroscopy (GC–MS) and a recombinant yeast estrogen reporter assay. As measured by GC–MS, background estrone concentrations were approximately 100 ppb, while 17β–estradiol concentrations were one–third of the estrone concentration, and 17β–estradiol concentrations were below the detection limit (10 …

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Evaluation Of Fabric Swatch Types For Relative Odor Intensity At Beef Cattle Feedyards, Sean D. See, David B. Parker, Brent W. Auvermann, Jacek A. Koziel, John Sweeten Jan 2001

Evaluation Of Fabric Swatch Types For Relative Odor Intensity At Beef Cattle Feedyards, Sean D. See, David B. Parker, Brent W. Auvermann, Jacek A. Koziel, John Sweeten

Jacek A. Koziel

A research project was conducted to determine which type of fabric swatch was best suited for on-site sampling of odor intensity at open-lot beef cattle feeding operations. Five different types of fabric were tested: cotton flannel, cotton muslin, acetate, polyester and polyester felt. Square swatches (20 × 20 cm) were suspended 1 m above the ground surface downwind of cattle pens for 24 hours. The swatches were placed in glass jars and presented to 8-10 human panelists who were asked to rank the swatches based on relative odor intensity. Five trials were conducted at 3 feedyards. Sums of ranks and …

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Air Sampling With Solid Phase Microextraction, Jacek A. Koziel, Fabio Augusto, Janusz Pawliszyn Jan 2001

Air Sampling With Solid Phase Microextraction, Jacek A. Koziel, Fabio Augusto, Janusz Pawliszyn

Jacek A. Koziel

Solid phase microextraction (SPME) presents many advantages over conventional analytical methods by combining sampling, pre-concentration and direct transfer of the VOCs into a standard gas chromatography (GC) system. Since its introduction SPME has been applied to the sampling and analysis of environmental samples including airborne VOCs and particulates. The first part of this paper presents theory of air sampling with SPME and an overview of the a few current methods for quantitative air sampling and VOC determination with SPME using grab (‘instantaneous”) and time-weighted average (TWA) modes. The second part of this paper is focused on the recent development of …

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