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Articles 77701 - 77730 of 78533
Full-Text Articles in Entire DC Network
A Study Of Alveolar Bone Loss And Two-Hour Postprandial Blood Sugar Levels, R. Leslie Arnett
A Study Of Alveolar Bone Loss And Two-Hour Postprandial Blood Sugar Levels, R. Leslie Arnett
Loma Linda University Electronic Theses, Dissertations & Projects
Two-hour postprandial blood sugar determinations were carried out on 500 patients referred for periodontal care. The mean percentage of alveolar bone loss around the mandibular bicuspid teeth was established for each individual. The subjects were then grouped according to blood sugar levels and the mean alveolar bone loss was calculated. The group was separated into male and female sub-groups and data was computed for these segments as well as the total sample. The data was evaluated in a similar manner for those subjects between 40 and 49 years of age.
No Chi-square determinations were statistically significant but significance in differences …
The Synthesis Of 5- And 8-Dialhylamino-Alkylaminopyrido [2,3-D] Pyridazines As Potential Antimalarial Agents, William M. Rich
The Synthesis Of 5- And 8-Dialhylamino-Alkylaminopyrido [2,3-D] Pyridazines As Potential Antimalarial Agents, William M. Rich
Chemistry and Chemical Biology ETDs
The appearance of strains of malaria resistant to most of the synthetic antimalarial agents has prompted the investigation of new compounds for antimalarial activity. The structural similarities of the nucleus of pyrido [2,3-d] pyridazine to pteridine as well as to the known quinoline antimalarials suggested the possibility of development of potential chemotherapeutic agents based on the ring system.
A series of 5,8 substituted pyrido [2,3-d] pyridazines were prepared in which one substituent was a dialkylaminoalkylamino group and the other substituent either a chloro, ethoxy, or hydroxy group. Ultraviolet, infrared, and nuclear magnetic resonance spectra were reported for all compounds. Structures …
The Identification Of The Inorganic Components In The Calcareous Corpuscles From Mesocestoides Corti, Larry M. Kegley
The Identification Of The Inorganic Components In The Calcareous Corpuscles From Mesocestoides Corti, Larry M. Kegley
Dissertations and Theses
The inorganic components in calcareous corpuscles from Mesocestoides corti have been identified by use of powder x-ray diffraction and emission spectroscopy. Difference methods were compared for the isolation of the calcareous corpuscles from the residual tissue of the Mesocestoides corti. Previously reported and newly developed methods for the isolation are discussed.
Analyses by powder x-ray diffraction for in vivo samples which had been heated at various temperatures ranging from room temperature to 1000°C are reported.
The qualitative emission spectrographic analyses for in vivo and in vitro corpuscles are reported for normal systems and systems designed to study the ion …
Bacterial Degradation Of Methyl Dehydroabietate, Burl C. Carter
Bacterial Degradation Of Methyl Dehydroabietate, Burl C. Carter
Dissertations and Theses
Bacteria (Arthrobacter sp.), isolated from lodgepole pine (Pinus contortus), are capable of utilizing methyl dehydroabietate as the sole source of carbon. Degradation products of methyl dehydroabietate have been obtained by manually extracting the cell-free supernatant solution of a liquid growth medium with methylene chloride. Gas chromatography (G. L. C.) was used for separation of the neutral products. The acid products were converted to their methyl esters diazomethane and then separated by gas chromatography. Structures have been proposed for two G. L. C. fractions (V, II) on the basis of infrared (I.R.) and mass spectral (M. S.) data. …
The Prairie Naturalist Volume 1, No. 2. May, 1969
The Prairie Naturalist Volume 1, No. 2. May, 1969
The Prairie Naturalist
EDITORIAL: North Dakota's Naturalist-at-Large ▪ Paul B. Kannowski
WETLAND VEGETATION OF THE TURTLE MOUNTAINS, NORTH DAKOTA ▪ Robert L. Burgess and Dennis T. Disrud
RAPID METHOD OF FILTRATION OF MARSH WATERS ▪ V. A. Adomaitis and J. A. Shoesmith
NOTES
Additional distribution records of the false map turtle and the short-horned lizard in North Dakota ▪ Dennis J. Gemmell
Summer record of the snowy owl in North Dakota ▪ Donald R. Johnson
Long-billed curlews in LaMoure County, North Dakota ▪ Gary L. Krapu
Isolation And Partial Characterization Of The Toxic Substance From Eremocarpus Setigerus Benth, Shuliang Lee
Isolation And Partial Characterization Of The Toxic Substance From Eremocarpus Setigerus Benth, Shuliang Lee
Loma Linda University Electronic Theses, Dissertations & Projects
The work on the active substance of Eremocarpus setigerus Benth has been previously performed by Naito and Noller. However, the investigation was not complete. Therefore we isolated and tested this substance by steam distillation and thin layer chromatography technique. A yellow sticky toxic substance was isolated with Rf values of 0.15 in benzene system and 0.57 in benzene-absolute ethanol (95:5 v/v) system.
The toxic substance which is free of halogen, nitrogen, and sulfur, is soluble in ethyl ether, ethanol, and concentrated sulfuric acid. It has a maximum absorption in the ultraviolet region that indicates the presence of unsaturation. Its infrared …
Sex Determination By Cephalometry And Odontometry, Clair R. Hopkins Jr.
Sex Determination By Cephalometry And Odontometry, Clair R. Hopkins Jr.
Loma Linda University Electronic Theses, Dissertations & Projects
Plaster casts of teeth and lateral cephalometric roentgenograms were studied to see with what degree of accuracy sex could be determined. The sample considered was made up of one hundred and forth-four individuals--50 males and 94 females--being treated in the Graduate Orthodontic Department of the Loma Linda University School of Dentistry. The age range for the boys was from 15 to 19 and for the girls, from 14 to 20. Data was obtained for the following variables from tracings of the roentgenograms and from the dental casts:
- Glabello-occipital length
- Articulate to nasion
- The gonial angle of the mandible
- Prosthion to …
The Eightieth Session Of The Iowa Academy Of Science And The Thirty-Sixth Convention Of The Iowa Junior Academy Of Science, April 19-20, 1968 [Pamphlet], Iowa Academy Of Science
The Eightieth Session Of The Iowa Academy Of Science And The Thirty-Sixth Convention Of The Iowa Junior Academy Of Science, April 19-20, 1968 [Pamphlet], Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
The Eightieth Session Of The Iowa Academy Of Science And The Thirty-Sixth Convention Of The Iowa Junior Academy Of Science, April 19-20, 1968 [Program], Iowa Academy Of Science
The Eightieth Session Of The Iowa Academy Of Science And The Thirty-Sixth Convention Of The Iowa Junior Academy Of Science, April 19-20, 1968 [Program], Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
The Approximate Scf Lcao-Mo With Cndo Theory And Electronic Structures Of N-Heterocyclic Benzene Analogues, Jay Jea-Yong Rhee
The Approximate Scf Lcao-Mo With Cndo Theory And Electronic Structures Of N-Heterocyclic Benzene Analogues, Jay Jea-Yong Rhee
Chemistry and Chemical Biology ETDs
The approximate MO theory in this study expIicitly refers to the Pople molecular orbitaI treatment. This consists of complete neglect of differential overlap (CNOO) in the self-consistent field treatment of the molecular orbitals, analogous to the Hartree-Fock treatment of atomic systems, which are constructed as Iinear combinations of atomic orbitals (LCAO). Furthermore, the only orbital functions considered in a basis set are those for the valence electrons and the atomic orbitals are Slater-type orbitals. The major investigation of this study is to apply this approximate MO theory to the series of nitrogen heterocyclic benzene analogues. The quantities that have been …
"Planetary Exploration (Lecture Two)", Carl Sagan
"Planetary Exploration (Lecture Two)", Carl Sagan
Special Collections: Oregon Public Speakers
Requested by: "Standing order from Science" "Planetary Exploration"
"Planetary Exploration (Lecture One)", Carl Sagan
"Planetary Exploration (Lecture One)", Carl Sagan
Special Collections: Oregon Public Speakers
No abstract provided.
The Ias Bulletin, V2n2, March 1968, Iowa Academy Of Science
The Ias Bulletin, V2n2, March 1968, Iowa Academy Of Science
IAS Bulletin
In this issue:
--- Features pf the Eightieth Session
--- Special Reminder to Program Participants
--- Junior Academy's Thirty-Sixth Convention
--- Awards and Recognition
--- Equipment and Book Displays
--- Proceedings Progress and Problems
--- Science Teachers Short Course a Success
--- More Regional ISTS Meetings
--- Reports from Second Articulation Conference Available
--- Motel Information
--- Pre-Registration
Fluorescence Studies Of Cobalt (Iii) Complexes, Arnold T. Weibel
Fluorescence Studies Of Cobalt (Iii) Complexes, Arnold T. Weibel
Masters Theses
No abstract provided.
The Prairie Naturalist Volume 1. No.1. March 1968
The Prairie Naturalist Volume 1. No.1. March 1968
The Prairie Naturalist
EDITORIAL: Another Milestone ▪ John T. Lokemoen
NESTING OF THE COMMON SNIPE IN NORTH DAKOTA ▪ Robert E. Stewart and Harold A. Kantrud
SCIENCE WRITING — A PROBLEM ▪ Soren O. Kolstoe
INSECTICIDES: A DOUBLE-EDGED SWORD ▪ Richard D. Urban
NOTES
Why I like the Badlands ▪ Wayne Hecker
White-faced ibis in McIntosh County, North Dakota ▪ Harold F. Duebbert
Cinnamon teal observations in North Dakota ▪ A. T. Klett and John T. Lokemoen
Trumpeter swan in Kidder County, North Dakota ▪ Lewis M. Cowardin and James C. Bartonek
Specimen records of greater scaup ▪ Charles W. Dane and Harold …
Biometrical Genetics Of Insecticide Resistance:A Quantal Response Character., N Singh Dr.
Biometrical Genetics Of Insecticide Resistance:A Quantal Response Character., N Singh Dr.
Doctoral Theses
Geneses of the Froblems1.1.1 Resistence -A poblem in the fields of publio hosl th, agriculture, and endmel husbandry Discovery of the synthetic insecticides of residual toxcicity and their availability for civilian use after the World Mar I had presented a bright proapeot of freedom from insect bome diseases, Lindted fleld trials of chlorinated hydrocarbon insecticides in the sphere of ublic heal th had resulted in decline of the veotor/post pepulations by 'erdsia! and oonsaquentay the incidonce of vector borne diseases recorded drameatic falls. Inspired by such good results different combries and World Heoalth Organi zntion (WED) embarked upon the adventuro …
The Systematics Of Sympatric Species In West Indian Spatangoids: A Revision Of The Genera Brissopsis, Plethotaenia, Paleopneustes, And Saviniaster, Richard H. Chesher
The Systematics Of Sympatric Species In West Indian Spatangoids: A Revision Of The Genera Brissopsis, Plethotaenia, Paleopneustes, And Saviniaster, Richard H. Chesher
Studies in Tropical Oceanography
No abstract provided.
Problems Of Pollution: Benefits, Risks And Regulations, Richard E. Pogue, Dean E. Abrahamson
Problems Of Pollution: Benefits, Risks And Regulations, Richard E. Pogue, Dean E. Abrahamson
Journal of the Minnesota Academy of Science
The growing concern of the scientific community and informed segments of the public about the proliferation of untested nuclear power plants demands further evaluation of their environmental impact before irrevocable decisions are mode. This paper considers the problem of low-level radioactive wastes controllable at the source. A brief background is given of the governmental agencies concerned with radiation monitoring and protection. The underlying philosophy behind radiation protection and the guidelines for putting this philosophy into practice are considered. The risk implicit in these guidelines is assessed in terms of the expected increased incidence of specific injuries to human populations.
Biological Aspects Of Heat Pollution, Theodore Olson
Biological Aspects Of Heat Pollution, Theodore Olson
Journal of the Minnesota Academy of Science
The importance of temperature as an environmental factor has long been recognized by the ecologist, and its special impact upon the aquatic ecosystem has been of interest to aquatic biologists since they first began to observe interactions between living things and the physical environment. Interest in water temperatures as an environmental factor has recently become more widespread; and one aspect of the phenomenon, namely "thermal pollution," has attracted special attention.
Discharge Of Radioactive And Thermal Wastes, Richard E. Pogue, Dean E. Abrahamson
Discharge Of Radioactive And Thermal Wastes, Richard E. Pogue, Dean E. Abrahamson
Journal of the Minnesota Academy of Science
A combination of several economic factors, together with growing concern about air pollution associated with conventional, fossil-fuel electric generating facilities, hos contributed to the increase in size and number of nuclear-powered plants. Although these nuclear plants are "clean" from the standpoint of conventional air pollutants, they must dispose of thermal and radioactive wastes. This paper outlines the sources and quantities of these wastes, based on technical data for the boiling-water reactor proposed for Monticello, Minnesota.
The Cedar Creek Natural History Area: A Progress Report, William H. Marshall
The Cedar Creek Natural History Area: A Progress Report, William H. Marshall
Journal of the Minnesota Academy of Science
During the past five years, the utilization of the Cedar Creek Natural History Area by educators, research workers, and special, groups has increased steadily. Progress in administration, management, operations, and land acquisition is described in this paper, and the needs for the future are indicated.
Morphology And Water Quality In Three Abandoned Granite Quarries, Keith M. Knutson
Morphology And Water Quality In Three Abandoned Granite Quarries, Keith M. Knutson
Journal of the Minnesota Academy of Science
Limnological conditions were studied in two abandoned granite quarries in George Friedrich Park, St. Cloud, Minn. These quarries were excavated from 1886 to 1890 and left shallow due to inadequate water pumping systems at the time. The quarries were less than one hectare in area and had mean depths of 7.3 and 8.2 m. The annual heat budget was about the same for both quarries, 10,535 gm. cal/cm•. Concentrations of [chemical symbols] were determined. Very low concentrations of nitrate nitrogen were found ([chemical symbols]). The hypomimia of both quarries contained hydrogen sulfide throughout the study. Data show West Quarry to …
The Certified Strains Of Subterranean Clover : Their Origin, Potential Use And Identification, B J. Quinlivan, C. M. Francis, M. L. Poole
The Certified Strains Of Subterranean Clover : Their Origin, Potential Use And Identification, B J. Quinlivan, C. M. Francis, M. L. Poole
Journal of the Department of Agriculture, Western Australia, Series 4
SUBTERRANEAN CLOVER originated in the countries surrounding the Mediterranean Sea and in parts of Western Europe.
Therefore it is not surprising that it grows well in the agricultural districts of Western Australia, for these regions have a typically Mediterranean climate with cool wet winters and hot dry summers.
West Midlands Development : Pastures For Sandplain Soils, Department Of Agriculture, Western Australia
West Midlands Development : Pastures For Sandplain Soils, Department Of Agriculture, Western Australia
Journal of the Department of Agriculture, Western Australia, Series 4
TRIALS at the Badgingarra Research Station have indicated that many pasture species will grow in the West Midlands area.
Choice of the species most suited to any particular locality will be influenced by soil type, rainfall, grazing characteristics and possible ill-effects on stock.
The following species have been recommended.
Ecological Study Of The Effects Of Strip Mining On The Microbiology Of Streams, Ralph H. Weaver, Harry D. Nash
Ecological Study Of The Effects Of Strip Mining On The Microbiology Of Streams, Ralph H. Weaver, Harry D. Nash
KWRRI Research Reports
The microflora of Cane Branch of Beaver Creek in McCreary County, Kentucky, which drains an area that was strip-mined between 1955 and 1959, was studied and compared with that of Helton Branch which drains a comparable area where there has been no mining. Differences include: the establishment of Ferrcbacillus ferrooxidans, for which procedures were developed for direct colony isolation from the stream; fewer saprophytic bacteria; more numerous and more diversified filamentous and unicellular fungi; and characteristic differences in algal flora. Representatives of 42 genera of filamentous fungi were identified. Of these, 21 were isolated only from Cane Branch. Representatives of …
Arkansas Trilobite From Lower Ordovician Rocks, John D. Taylor
Arkansas Trilobite From Lower Ordovician Rocks, John D. Taylor
Journal of the Arkansas Academy of Science
No abstract provided.
The Fish Population Of Lake Poinsett, South Dakota, As Indicated By The Catch, James C. Congdon
The Fish Population Of Lake Poinsett, South Dakota, As Indicated By The Catch, James C. Congdon
Electronic Theses and Dissertations
Gill nets, trap nets, an otter trawl, and a boom-type electric shocker were utilized to obtain samples of the fish population of Lake Poinsett, South Dakota. The species and size composition of the samples differed significantly with time of season, time of day, location on the lake, and type of gear. Decreased activity following spawning was the apparent cause of a midsummer decline in gill net and trap net catches of black bullhead, black crappie, and white crappie. A late summer increase in the catch of yearling black bullheads, crappies, white bass, carp and bigmouth buffalo was attributed to an …
Evaluations Of Techniques For Estimating Fall Age Ratios Of Canada And Snow Geese, Kenneth Frederick Higgins
Evaluations Of Techniques For Estimating Fall Age Ratios Of Canada And Snow Geese, Kenneth Frederick Higgins
Electronic Theses and Dissertations
Validity of flock counts, average group-size counts, cannot-net catches, and hunter-bag checks for estimating productivity of lesser snow geese (Anser caerulescens caerulescens) and small Canada geese (Branta cnadensis hutchinsii-parvipes complex) was studied at Sand Lake and Tewaukon National Wildlife Refuges during fall, 1965 and 1966. Age-ratios obtained from flock counts vaired with the number of flocks sampled, wind velocity and amount of sky cover. If adequate sampling sites are selected and weather conditions are standardized, age ratio data from flock counts are of value for assessing productivity. Variation in group composition and number contributed to the bias in average group-size …
Life History And Ecology Of The Black-Footed Ferret In The Wild, Conrad N. Hillman
Life History And Ecology Of The Black-Footed Ferret In The Wild, Conrad N. Hillman
Electronic Theses and Dissertations
Twenty-one black-footed ferrets (Mustela nigripes) were observed at six different locations in southwest South Dakota between April 1966, and September 1967. All observations were made on black-tailed prairie-dog (Cynomys ludovicianus) towns from 15 to 100 acres in size. Because of the proximity of towns inhabited by ferrets, it was possible that individual animals were observed in more than one location. Three litters of ferrets were studied. Young ferrets were most active during early morning and late evening hours. Ferrets remained as a group until early fall when dispersal evidently occurred. Young ferrets accepted live-tethered and dead prairie dogs, mice, cottontails …
A Survey Of Pollution On Selected Streams In The Black Hills Of South Dakota, Thomas J. Jurgens
A Survey Of Pollution On Selected Streams In The Black Hills Of South Dakota, Thomas J. Jurgens
Electronic Theses and Dissertations
Seven Streams in the Black Hill of South Dakota were surveyed to determine the influence of suspected sources of pollution on these streams. The sources of pollution included both sewage treatment plant effluents and mining wastes. A comparison of the benthic fauna community below a pollution source to that above it was the primary basis for evaluating the effect of the pollution source on the stream. The results of the benthic fauna samples indicated that the streams surveyed were being polluted. The degree of pollution of each stream was also indicated by these results. Chemical analysis were sued to verify …