• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • No language data
  • Tagged with
  • 367
  • 367
  • 367
  • 367
  • 367
  • 43
  • 21
  • 21
  • 18
  • 18
  • 17
  • 13
  • 13
  • 13
  • 13
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Notes on the biology of the lake trout and other selected salmonids in Indiana waters of Lake Michigan

Miller, William G. 03 June 2011 (has links)
Lake trout (Salvelinus namaycush), chinook salmon (Oncorhynchus tschawytscha), coho salmon (Oncorhynchus kisutch), steelhead trout (Salmo gairdneri), and brown trout (Salmo trutta were collected from April 30 to November 18, 1970 with gill nets at selected sites in Lake Michigan near Gary, Burns Ditch, and Michigan City, Indiana. Catch-per-uniteffort was law and most catches occurred when nets were set in water temperatures in the 50 F (10.0 C) range or lower. Sea lamprey (Petrcnyzon marinas) scars and wounds were found on 25.4% of 71 lake trout captured and fresh wounds occurred on 6.0% of the fish. Scars and wounds were restricted to lake trout 20.0 in. (50.6 cm) or greater in total length and 32.7% of the 55 fish in this size group carried scars or wounds.Food items in stomachs of 39 lake trout, 34 coho salmon, and 29 chinook salmon were expressed as percent frequency of occurrence, numerical percent, and volumetric percent. The alewife (Alosa pseudoharenp_us) was the predominate food consumed by all three species. The crustaceans, Mysis sp. and Pontoporeia affinis, were consumed only by lake trout less than 19.0 in. (48.1 cm) total length.The age and growth of 69 known age fin clipped lake trout were examined. The body-scale relationship was TL = 6.2001 + 0.1238 Sc. The mean calculated total lengths for the first 5 years of growth were 5.3, 10.7, 16.3, 21.0, and 24.0 in. (13.5, 27.2, 41.4, 53.2, and 60.8 cm). Annual growth is considerably greater than recorded for Lake Michigan lake trout prior to alewife introduction and dominance. The length-weight relationship was log W = -2.5087 + 3.2338 log L which agrees closely with previous length-weight analyses of Lake Michigan lake trout.Ball State UniversityMuncie, IN 47306
122

Mechanism of decomposition of selected 1-pyrazolmes

Cheng, Theresa C-M 03 June 2011 (has links)
The kinetic study of thermal decomposition of compounds (A)-(E) had been examined. The thermal decomposition product of 1,1-dimethyl-5-(1-isobutenyl)-1-pyrazoline is 1,1-dimethyl5-(1-isobutenyl)cyclopropane, no hydrogen transfer or rearrangement was occured. The only isolated thermal decomposition product of 3-methyl-3,4-dicarboxylic anhydride-l-pyrazoline was dirnethylmaleic anhydride. Since carbon dioxide was found in the decomposition process and the amount of nitrogen gas and carbon dioxide was not the same, it indicated that the decarboxylation product was not come from the nitrogen freed anhydride product.Ball State UniversityMuncie, IN 47306
123

The analyses of tributary outfalls as possible sources of microbiological contamination of Grand Lake-St. Marys

Loughran, James P. 03 June 2011 (has links)
The outfalls of the eight tributaries entering Grand Lake-St. Marys were monitored during the eleven month period from August, 1972 through June, 1973. Both biological and physical parameters were measured at all sites.The biological parameters that were measured included; fecal coliforms, fecal streptococci, Salmonella spp., Shigella spp., Proteus spp., seudomonas,aeruginosa and Staphylococcus aureus. The physical parameters were; pH, turbidity, water temperature, dissolved oxygen and local rainfall.All eight outfalls were shown to exceed the limits recommended by the U.S. Public Health Service for fecal coliform counts. The ratio of fecal coliforms to fecal streptococci suggested that the pollution came from both human and animal wastes that were carried into the lake in stormwater runoff. The low fecal counts obtained away from the tributaries, in the center of the lake, indicated that the lake was able to recover from the pollution entering at the outfalls. Primary contact recreation in the vicinity of the tributary outfalls is not recommended but the remainder of the lake presents no apparent health hazard.Ball State UniversityMuncie, IN 47306
124

A quantitative survey of aberrant chromosome behavior in the Rhoeo spathacea population at Ball State University

Robinson, Sandra Kay 03 June 2011 (has links)
Using the acetocarmine squash technique to examine pollen mother cells, the meiotic chromosome behavior of each of 16 Rhoeo spathacea plants housed in the Ball State University greenhouse was analyzed with respect to the frequencies of several types of atnormalities and documented with suitable photomicrographs. Among the aberrant types of chromosome behavior resulting from multiple translocations among the 12 chromosomes of each plant were the followings ring and chain formation of chromosomes at diakinesis and metaphase I, adjacent versus alternate chromosome alignment patterns at metaphse I and anaphase I, various abnormal anaphase I and telophase I disjunction patterns, and the presence of excluded chromosomes and micronuclei at telophase I. As a further consequence of the multiple translocations and abnormal chromosome disjunction, many of the pollen grains formed by meiosis were found to be defective and non-viable.Ball State UniversityMuncie, IN 47306
125

Electronic circuits designed to improve the time resoluion in nuclear lifetime studies

Craig, Edwin L. 03 June 2011 (has links)
In this research a unique linear pulse amplifier was developed that significantly reduces the spread in pulse amplitudes of those pulses selected from a Ge(Li) detector by a single channel analyzer. This circuit utilizes an operational amplifier with its closed-loop gain automatically controlled by a P-channel junction field.-effect transistor. The amplification is adjusted for each pulse such that the output pulses are constant in amplitude. The performance of the system was analyzed with a multichannel analyzer and it was shown that an improvement in pulse amplitude variation of as much as 29.1 percent was achieved.Ball State UniversityMuncie, IN 47306
126

Thermodynamic considerations in devising on external combustion gas turbine engine refuse incinerator

Craig, Gale M. 03 June 2011 (has links)
Study and experiment indicate that, with existing technology, a modified open Brayton cycle can be used to burn common municipal refuse at atmospheric pressure and produce useful power while scrubbing the combustion product gases to remove pollutants.The hot combustion gases pass from a combustor through a turbine to a region below atmospheric pressure where they are scrubbed and cooled by mixing with water spray. The water spray and gas mixture is then exhausted to atmospheric pressure through a compressor.Although current compressor designs are workable in this application, a new design is needed which will have reduced water drag power loss.Ball State UniversityMuncie, IN 47306
127

Histologic and ultrastructural studies of nictitans gland of dog

Jen, Ling Sun 03 June 2011 (has links)
Nictitans glands obtained from mongrel dogs were studied grossly and by regular histological and electron microscopic methods. Special stains including Periodic Acid-Schiff and Sudan Black B were used for the identification of specific macromolecular components.The nictitans gland is a compound tubulo--alveolar gland of apocrine type, although holocrine type of secretory activity is exhibitedby a portion of the gland. Two kinds of secretory materials were secreted by two different types of acinar cells in this gland.The main function of this gland is to secrete lubricant and to keep the eyes in a healthy state. It is thus considered as a supplementary structure to the lacrimal gland.Ball State UniversityMuncie, IN 47306
128

Transferable drug resistance among animal and human strains of Escherichia coli

Porter, Timothy E. 03 June 2011 (has links)
This study was conducted to assess the incidence of infectious drug resistance among animal strains of Escherlchia coli. Fecal samples were examined from a cattle feedlot southeast of Muncie, Indiana. The use of tetracycline and sulfonamide compounds as feed additives was a common practice on this farm, and theoretically could provide the antibiotic pressure necessary to select for resistant strains. A total of 32 feedlot E. coli were isolated from the feedlot floor. In addition, 10 strains of E. coli isolated from patients with urinary tract infections were introduced into this investigation for comparative purposes. All isolates were tested for antibiotic susceptibility using disc-diffusion methods. Multiple resistant strains were designated as donor organisms and were used in conjugation experiments with an antibiotic sensitive recipient E. coli; wild type K-12 F-.Multiple drug resistance occurred among 21.8 percent of the feedlot E. coli isolated, with a predominance of resistance to chlorotetracycline, tetracycline, and sulfathiazole. Three out of seven multiple resistant donors isolated were able to transfer their antibiotic resistance markers to the recipient K-12 strain. Transferable drug resistance among the clinical isolates occurred in 6 of the 10 donor resistant strains, with tetracycline and ampicillin being the most frequently encountered resistance.Ball State UniversityMuncie, IN 47306
129

Nuclear lifetime measurement of the 1314-KeV level of 144 Nd

Collins, Jack P. 03 June 2011 (has links)
A delayed-coincidence spectrometer system was used to measure nuclear lifetimes in the picosecond region by the centroid-shift method. Timing signals were derived from two plastic scintillators; each plastic scintillator was located within a specially constructed NaI(Tl) detector. Each NaI(Tl) detector was used to detect the gamma ray which Compton scattered from an associated plastic scintillator. Energy identification was achieved by summing the signals from the plastic and the NaI(Tl) detectors to give full energy gamma-ray photopeaks. To test the effectiveness of the system, the half-lives of the first excited state of 134Ba and the first and second excited states of 144Nd were measured. The half life of the first excited state of 134Ba was measured as 4.4 - 1.3 psec; this result is in agreement with a previously reported value of 5.0 t 1.5 psec. The half-life for the first excited state of 144Nd was determined to be 1.5 ± 1.0 psec while the half-life for the second excited. state of 144Nd was determined to be 5.1 ± 0.5 psec. The half-life value for the second excited state of 144Nd is in disagreement with previously reported values of 21 ± 2 psec and 100 ± 30 psec which were also determined by delayed-coincidence methods. Although the result of 1.5 ± 1.0 psec for the first excited state lifetime differed from a previous result of 3.4 * 0.1 psec obtained by Coulomb excitation, this difference was due to the inability of the present spectrometer system to resolve the 618- and 696-keV gamma rays of 144Nd. It is concluded that a lower lifetime limit measurable with the system described in this study is about one picosecond, provided that the gamma rays can be resolved in the sum energy spectrum of the plastic and NaI(T1) detectors.Ball State UniversityMuncie, IN 47306
130

Sigmodon hispidus in relation to vegetation in Belize District, Belize

Brier, John C. 03 June 2011 (has links)
Cotton rats, Sigmodon hispidus, were trapped and studied in Belize District, Belize, Central America from June 14, 1973 to July 13, 1973. Vegetation in the area was surveyed to determine height, extent of matting, and species composition. Comparisons were then made between vegetation and S. hispidus captures. A total of 48 S. hispidus,were captured, primarily in areas of tall and matted grass. S. hispidus appeared to be absent from areas of short grass.Reproduction, body size, sex ratio, parasites, and behavior of S. hispidus are discussed. Other mammals taken during the study included two specimens of Or_yzomys, fulvescens,, a species which had not previously been collected in Belize.Ball State UniversityMuncie, IN 47306

Page generated in 0.1174 seconds