Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 38851 - 38880 of 42697

Full-Text Articles in Entire DC Network

Summer 1988, Nsu Oceanographic Center Jan 1988

Summer 1988, Nsu Oceanographic Center

Currents

No abstract provided.


Spring 1988, Nsu Oceanographic Center Jan 1988

Spring 1988, Nsu Oceanographic Center

Currents

No abstract provided.


Fall 1988, Nsu Oceanographic Center Jan 1988

Fall 1988, Nsu Oceanographic Center

Currents

No abstract provided.


Roles Of A 67-Kda Polypeptide In Reversal Of Protein Synthesis Inhibition In Heme-Deficient Reticulocyte Lysate, Bansidhar Datta, Debopam Chakrabarti, Ananda L. Roy, Naba K. Gupta Jan 1988

Roles Of A 67-Kda Polypeptide In Reversal Of Protein Synthesis Inhibition In Heme-Deficient Reticulocyte Lysate, Bansidhar Datta, Debopam Chakrabarti, Ananda L. Roy, Naba K. Gupta

Department of Chemistry: Faculty Publications

During heme deficiency in reticulocyte lysates, the heme-regulated protein synthesis inhibitor, HRI, phosphorylates the a subunit of eukaryotic initiation factor 2 (eIF-2) and thus inhibits protein synthesis. Two factors, eIF-2 and a reticulocyte-lysate supernatant factor that we term RF, reverse this inhibition. We now report the following. (i) An active eIF-2 preparation contained, in addition to the three subunits (α,β, and γ), a 67-kDa polypeptide. Pretreatment of eIF-2 with polyclonal antibodies against either isolated a subunit or 67-kDa polypeptide almost completely inhibited the reversal activity. Upon further fractionation, three-subunit eIF-2 and the 67-kDa polypeptide were resolved. Neither the …


Evolutionary Genetics And Morphometrics Of A Cave Crayfish Population From Chiapas (Mexico), Valerio Sbordoni, Giuliana Allegrucci, Fabiola Baldari, Donatella Cesaroni Jan 1988

Evolutionary Genetics And Morphometrics Of A Cave Crayfish Population From Chiapas (Mexico), Valerio Sbordoni, Giuliana Allegrucci, Fabiola Baldari, Donatella Cesaroni

International Journal of Speleology

The recently explored Cueva de Los Camarones, in the remote village of Constitucion, Chiapas, Mexico, houses a unique highly variable population of Procambarus crayfish (Crustacea, Decapoda). Morphologically, a more or less clinal variation is revealed at several features such as the degree of rudimentation in both pigmentation and eye, and the elongation of body and appendages. Extremes are quite different, ranging from typical dark, thick, eyed individuals to light, elongated, microphtalmic phenotypes. Evolutionary relationships among individuals were investigated electrophoretically (25 structural gene loci) and morphometrically (12 characters) by means of multivariate analyses. Results from analysis of individual allozymic multilocus profiles …


Stratigraphy, Paleontology And Paleobiogeography Of Lower Vertebrates From The Cedar Mountain Formation (Lower Cretaceous), Emery County, Utah, Michael L. Pomes Jan 1988

Stratigraphy, Paleontology And Paleobiogeography Of Lower Vertebrates From The Cedar Mountain Formation (Lower Cretaceous), Emery County, Utah, Michael L. Pomes

Master's Theses or Doctor of Nursing Practice

Where present, the basal Buckhorn Member of the Cedar Mountain Formation (Aptian-Albian) separates the overlying main member from the mudrocks of the Tithonian Brushy Basin Member of the Morrison Formation. Without the Buckhorn, the mudrocks of the Cedar Mountain Formation appear to grade into those of the Morrison, so one is apt to call the entire sequence Morrison. Where the Cedar Mountain Formation appears to grade in to the Morrison, use of lower vertebrate teeth can provide an additional means to separate the Morrison from the Cedar Mountain Formation. Lower vertebrate teeth and associated microvertebrate remains (eggshell and bone fragments) …


Production Effects Of Biotechnology In The Dairy Industry: An Exploratory Study, Kenneth L. Schurter Jan 1988

Production Effects Of Biotechnology In The Dairy Industry: An Exploratory Study, Kenneth L. Schurter

Theses

Genetically engineered products are being produced at an economical level. products is bovine sornatotropin. One of these Injections of bovine sornatotropin increase milk yield in dairy cattle. This increase in production per cow is consistent with the thirty year trend of fewer dairy farms, fewer cows, and more milk per cow.

Starting in the 1950's in the mechanical era, farmers went from horses to tractors. In the chemical era, herbicides and fertilizers started being used. Now in the 1980's the technical era is coming in to existence . Through all of these era's there was controversy. Each of these era's …


Macropaleontology Of The Gunn Member, Stony Mountain Formation (Upper Ordovician), Manitoba And North Dakota, Frederick K. Lobdell Jan 1988

Macropaleontology Of The Gunn Member, Stony Mountain Formation (Upper Ordovician), Manitoba And North Dakota, Frederick K. Lobdell

Theses and Dissertations

The Gunn Member of the Stony Mountain Formation has long been known to contain an abundant and diverse fauna. This study was undertaken to identify and describe the macrofauna of the Gunn Member in the subsurface of North Dakota, previously neglected.

As a necessary first step, collections of fossils from outcrop were examined and identified. With the outcrop fauna serving as a reference collection, twenty cores from the North Dakota subsurface were examined, described, and their fossils sampled. Fossil and sediment samples were washed and sieved and the residues were picked for microscopic representatives of phyla usually considered to be …


The Effects Of Siltation On Recruitment Of Spiny Lobsters, Panulirus Argus, William F. Herrnkind, Mark J. Butler, Richard A. Tankersley Jan 1988

The Effects Of Siltation On Recruitment Of Spiny Lobsters, Panulirus Argus, William F. Herrnkind, Mark J. Butler, Richard A. Tankersley

Biological Sciences Faculty Publications

Fewer juvenile pinry lobsters were found in areas of the Florida Keys where their primary habitat was heavily silted as compared with similar, less silted habitat. Several hypotheses explaining this relationship were tested, and the time-to-metamorphosis was compared for settling pueruli within silted and nonsilted algae stands. Limited postlarval settlement and avoidance of silted algal habitats by juveniles, probably accounts for the paucity of young lobsters in heavily silted sites. In addition, although juvenile lobsters are nonselective predators, lower prey availability in silted algae probably promotes transciency which, in turn, causes increased mortality by predation while juveniles are exposed.


Fractals With Arbitrary Segment Lengths, Daniel Michael Doerer Jan 1988

Fractals With Arbitrary Segment Lengths, Daniel Michael Doerer

Masters Theses

"Work in the area of fractal geometry has generally focused on a specific facet of the discipline at the expense of other interesting features. This approach often generates more questions than answers for the general audience due to the lack of unification across all views. It appears that a common thread to relate all aspects of fractal characteristics is missing. This paper addresses this question and presents some new and fascinating results. For example, in-depth mathematical analysis often defers to the intriguing and attractive graphical displays produced by mapping the complex plane to the pixel field on a CRT. Both …


Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong Jan 1988

Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong

Grain and other field crops research reports

In the past couple of years research into lupins has increased substantially particularly in the fields of weed control, seeding rates, and control of diseases such as brown leaf spot and pleiochaeta root rot. This report is a summary of the lupin trials in the Lake Grace advisory area as well as a guide to better lupin farming.


Code Lists For Computerized Soil And Land Resource Data Recording, Peter D. King, M R. Wells Jan 1988

Code Lists For Computerized Soil And Land Resource Data Recording, Peter D. King, M R. Wells

Resource management technical reports

No abstract provided.


Evaluation Of Possible Reproductively Mediated Character Displacement In The Crayfishes, Orconectes Rusticus And O. Sanbornii, Mark J. Butler Iv Jan 1988

Evaluation Of Possible Reproductively Mediated Character Displacement In The Crayfishes, Orconectes Rusticus And O. Sanbornii, Mark J. Butler Iv

Biological Sciences Faculty Publications

Orconectes rusticus is replacing several species of crayfishes in north-central and northeastern North America, including O. sanbornii in Ohio. Recent evidence suggests that the species replacements may be driven by asymmetrical reproductive success favoring O. rusticus. Nonetheless, some sympatric associations appear locally persistent. Because crayfish demonstrate size assortative mating and there is a disparity in the sizes of the species, further divergence in the sizes of the species in sympatry could enhance reproductive isolation, ultimately providing a mechanism for character displacement. To test this hypothesis the size differentials between crayfish collected from allopatric and sympatric populations in east-central Ohio …


River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada Jan 1988

River Discharge Study, Laughlin, Nevada: Colorado River Model And Diffusion Study, B. Dennis Hugh, David L. Stringfield, Jill C. Bicknell, Robert A. Ryder, Clark County Sanitation District, Nevada

Publications (WR)

A water quality modeling study of the Mohave Reach of the Lower Colorado River (from Davis Dam to the Nevada/California Stateline) was conducted to evaluate potential water quality impacts resulting from a proposed Laughlin, Nevada wastewater effluent discharge. The study included four major components: (1) review of the current regulatory framework; (2) a field data collection program to document existing water quality conditions in winter, summer, and fall; (3) development and verification of far-field and near-field (mixing zone) water quality models; and (4) application of the models to project future river quality conditions for several treatment-discharge alternatives as well as …


Fish Aid: The Lake Mead Fertilization Project, Richard Axler, Larry Paulson, Peter Vaux, Patrick Sollberger, Donald H. Baepler Jan 1988

Fish Aid: The Lake Mead Fertilization Project, Richard Axler, Larry Paulson, Peter Vaux, Patrick Sollberger, Donald H. Baepler

Publications (WR)

Sport fishing at Lake Mead in Nevada and Arizona is a resource valued at nearly $100 million per year to southern Nevada. During the past two decades, salmonids, mostly trout, have disappeared entirely, the largemouth bass catch has drastically declined despite greater fishing pressure, and the condition factors for striped bass have steadily deteriorated. It appears that a major reduction in phosphorus loading caused by the upstream impoundment of the Colorado River to form Lake Powell in 1963 and advanced wastewater treatment removal of phosphorus from domestic wastewater inflows in 1981 are the principal factors responsible for decreased production at …


Characterization Of The Lipopolysaccharides From Rhizobium Phaseoli Symbiotic Mutants, Francisca Garcia Jan 1988

Characterization Of The Lipopolysaccharides From Rhizobium Phaseoli Symbiotic Mutants, Francisca Garcia

Masters Theses

The lipopolysaccharides (LPSs) of the Rhizobium phaseoli CE3 and its mutants CE109, CE309 and the transconjugate Rhizobium leguminosarum LB2/109.11 were isolated and analyzed by gas chromatography (GC) and 1H nuclear magnetic resonance (NMR) spectroscopy. CE3 is the wild type strain which is nodulation-proficient (Nod+). Strain CE109 and CE309 have a transposon, Tn5, inserted into Region I and Region III of their respetive chromosomes. Mutants CE109 and CE309 are defective in nodule development (Ndv-). Transconjugate R. leg. LB2/109.11 has the DNA of the R. leg. LB2 wild type and also Region I portion of the CE109 …


Bacterial Biomagnetism And Geomagnetic Field Detection By Organisms, Richard P. Blakemore, Nancy A. Blakemore, Richard B. Frankel Jan 1988

Bacterial Biomagnetism And Geomagnetic Field Detection By Organisms, Richard P. Blakemore, Nancy A. Blakemore, Richard B. Frankel

Physics

No abstract provided.


Great Salt Lake Interisland Diking: Water Quality Considerations, Executive Summary, Utah Water Research Laboratory, J. P. Riley, J. I. Blandamer, W. J. Doucette, R. R. Dupont, A. W. Grover, J. Herrick, J. M. Ihnat, J. E. Mclean, M. W. Nath, S. R. Rushforth, J. L. Sims, R. C. Sims, W. A. Wurtsbaugh Jan 1988

Great Salt Lake Interisland Diking: Water Quality Considerations, Executive Summary, Utah Water Research Laboratory, J. P. Riley, J. I. Blandamer, W. J. Doucette, R. R. Dupont, A. W. Grover, J. Herrick, J. M. Ihnat, J. E. Mclean, M. W. Nath, S. R. Rushforth, J. L. Sims, R. C. Sims, W. A. Wurtsbaugh

Reports

No abstract provided.


Great Salt Lake Interisland Diking: Water Quality Considerations, John I. Blandamer, William J. Doucette, Ryan R. Dupont, Anthony W. Grover, James Herrick, Jean M. Ihnat, Joan E. Mclean, Michael W. Nath, Samuel R. Rushforth, Judith L. Sims, Ronald C. Sims, Wayne A. Wurtsbaugh Jan 1988

Great Salt Lake Interisland Diking: Water Quality Considerations, John I. Blandamer, William J. Doucette, Ryan R. Dupont, Anthony W. Grover, James Herrick, Jean M. Ihnat, Joan E. Mclean, Michael W. Nath, Samuel R. Rushforth, Judith L. Sims, Ronald C. Sims, Wayne A. Wurtsbaugh

Reports

No abstract provided.


Pseudosinella Revisited (Collembola, Entomobryinae), Kenneth Christiansen Jan 1988

Pseudosinella Revisited (Collembola, Entomobryinae), Kenneth Christiansen

International Journal of Speleology

Eight controversies are active in the study of macroevolution. These are: 1) the meaning of the term macroevolution, 2) the role of chance, 3) the role of stasis and gradualism, 4) whether significant change is Iimited to speciation events, 5) the environmental conditions where macroevolutionary change occurs, 6) whether Neodarwinian mechanisms are adequate to explain change, 7) the existence and nature of hierarchical evolutìonary processes, and 8) Darwin’s views about all this. After a brief examination of each of these issues we used the extensive data available for 9 species of European and Nearctic cave Pseudosinella to examine the third, …


Paleoenvironment And Speciation In The Cave Beetle Complex Speonomus Delarouzeei (Coleoptera, Bathysciinae), Christian Juberthie Jan 1988

Paleoenvironment And Speciation In The Cave Beetle Complex Speonomus Delarouzeei (Coleoptera, Bathysciinae), Christian Juberthie

International Journal of Speleology

In the eastern part of the Pyrenees (France) the author describes a scenario of speciation in the cave species complex Speonomus delarouzeei (Coleoptera Bathysciinae); the speciation processes have been initiated by a breakdown of the ecological equilibrium induced during three glacial-interglacial episodes. The scenario is the following: — during the first glaciation (2.3-2.1 MY), psychrophilic populations ancestral to S. brucki were selected over the highest elevation of the range, by means of cold effect which produced an adaptive demographic advantage; adaptive characters of troglobitic species (K strategy) take place presumably in relation to colonization of caves and M.S.S.; — during …


Mating Behaviour And Barriers To Hybridization In The Cave Beetle Of The Speonomus Delarouzeei Complex (Coleoptera, Catopidae, Bathysciinae), Lysiane Juberthie-Jupeau Jan 1988

Mating Behaviour And Barriers To Hybridization In The Cave Beetle Of The Speonomus Delarouzeei Complex (Coleoptera, Catopidae, Bathysciinae), Lysiane Juberthie-Jupeau

International Journal of Speleology

The complex Speonomus delarouzeei combines 6 species which were previously synonymized. Using behavioural data, based on 12 populations, the author assesses the validity of 4 species and points out the occurrence of 2 species as yet undescribed. Constant and important differences during the mating appear between these different species. They concern the number of behavioural steps, the duration, the number of clappings of antennae, the abdominal male movements and the rubbing of female abdomen. The results of crossing experiments between different species indicate a prezygotic reproductive isolation with atypical matings and no sperm deposit. Between the populations of S. delarouzeei …


Ion-Association Complexes Of Thallium And Mercury With Rhodamine 6g In Aqueous Solution, Nasrein El-Masri Jan 1988

Ion-Association Complexes Of Thallium And Mercury With Rhodamine 6g In Aqueous Solution, Nasrein El-Masri

University of the Pacific Theses and Dissertations

The present study involves the determination of traces of thallium and mercury in aqueous solution by forming ion-association complexes of these metals with rhodamine 6G (R6G) in the presence of iodide. Thallium(lll) and mercury(Il) are able to quench the fluorescence of R6G in the presence of iodide by forming ion—association complexes, and the degree of quenching correlates with the thallium(III) or mercury(II) concentrations . By using this method, the minimum amount of thallium- (III) that can be determined in aqueous solutions is approximately 4.00 X 10-6m, while the minimum amount of mercury(II) is approximately 3.00 X 10-6m. Thallium(I) cannot be …


The Probe, Issue 78 - December 1987 Dec 1987

The Probe, Issue 78 - December 1987

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
DECEMBER, 1987
3rd Wildlife Damage Control Conference
EPA
Audubon Magazine
Black Bears
APHIS Activity Report
Gray Squirrels
Letters to Ye Ed
Steel-jaw Traps
The American Veterinary Medical Assoc. Executive Beard revised its position statement on traps
Guard Dogs
Coyote Control by Air
Personnel


Nutrient Losses From Conventional And No-Till Cornfields, Robert L. Blevins, Wilbur Frye Dec 1987

Nutrient Losses From Conventional And No-Till Cornfields, Robert L. Blevins, Wilbur Frye

Soil Science News and Views

Farmers must be concerned about both the monetary loss and the threat of groundwater and surface water pollution associated with the loss of plant nutrients from their fields. There is also an increasing public concern about pollution and the role of agriculture in nonpoint-source pollution. Movement of water over the surface of the soil as well as through the soil profile increases the potential for loss of water-soluble nutrients, especially nitrates.


Depth Profiles And Soil Textures Of The Vernal Pools Of The Santa Rosa Plateau Preserve, Riverside County, California, Ralph Charles Workman Jr. Dec 1987

Depth Profiles And Soil Textures Of The Vernal Pools Of The Santa Rosa Plateau Preserve, Riverside County, California, Ralph Charles Workman Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this project was to study the edaphic and topographic characteristics of the 13 vernal pools on the Santa Rosa Plateau Preserve, thus documenting the role soil texture plays in vernal pool formation.

Several field and laboratory procedures were used to demonstrate that there is a higher percentage of clay present within vernal pools than in soils outside the margin of the pools, for 11 out of the 13 pools. Statistical tests showed that the percentage of clay was highly significant within the center soil of the pool as compared to the soil outside the margin of the …


Time Delayed Protein Complementation, Diana L. Lakusta Dec 1987

Time Delayed Protein Complementation, Diana L. Lakusta

Loma Linda University Electronic Theses, Dissertations & Projects

The time delayed complementation of plant proteins was tested in weanling Sprague-Dawley male rats by measuring growth rates as well as plasma and tissue free amino acids. Diets of pinto beans with rice, corn or wheat were pair-fed in combination or alternating 4 times a day at 6 and 11 am, and 4 and 9 pm for 4 weeks. Plasma, liver and muscle samples were obtained 2 hours postprandial, a time determined most suitable for sacrifice, and analyzed for free amino acids via ion-exchange chromatography. There were no significant differences in growth of rats fed combination or alternating diets.during week …


The Probe, Issue 77 - November 1987 Nov 1987

The Probe, Issue 77 - November 1987

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
NOVEMBER, 1987
Duck Hunting Regulations
Cranes
APHIS Activity Report
Bombardier Muskeg Tractor
Hunting License Sales
Letters to Ye Ed
Bird Species Endemic
Arizona Bear Society
A Pest Population Compensating for Mortality Due to Pest Control Measures
Cat Farm
Trupeter Swan colony
Animal Rights


Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation Nov 1987

Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation

Publications (WR)

Studies conducted by the University of Nevada-Las Vegas (UNLV), the Nevada Department of Wildlife (NDOW), the Arizona Game and Fish Department (AGFD), The Nevada Division of Environmental Protection (NDEP), and the United States Bureau of Reclamation (USBR) have identified decreased algal production as a major factor involved in the decline of the Lake Mead sport fishery. Phosphorus-laden silt particles in the Colorado River have been sedimenting out in Lake Powell since the completion of Glen Canyon Dam 286 miles upstream in 1963. This sharp decrease in phosphorus loading to Lake Mead (>5000 tons per year) has resulted in decreased …


Rodenticide Use In Agricultural Crops, Terrell P. Salmon Oct 1987

Rodenticide Use In Agricultural Crops, Terrell P. Salmon

Eastern Wildlife Damage Control Conference: 3rd (1987)

The in-crop use of pesticides is allowed only after establishment of a crop tolerance with supporting residue data for the crop. Residue data from different regions and pesticide application methods (hand treatment, aerial broadcast, etc.) are required. Most rodenticide uses have been considered as non-crop since they are generally applied in and around rodent burrows and runways. Because of this, rodenticides do not generally have tolerances or residue information for crop use. Recent inquiries by the Environmental Protection Agency (EPA), a review of current rodenticide labels, and new pesticide laws, suggest the need for reevaluating the question of in-crop use …