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An Overview Of The Endangered Species Act, Michael J. Brennan Jun 1996

An Overview Of The Endangered Species Act, Michael J. Brennan

Biodiversity Protection: Implementation and Reform of the Endangered Species Act (Summer Conference, June 9-12)

25 pages.


X-Ray Microscopy: Preparations For Studies Of Frozen Hydrated Specimens, A. Osanna, C. Jacobsen, A. Kalinovsky, J. Kirz, J. Maser, S. Wang Jun 1996

X-Ray Microscopy: Preparations For Studies Of Frozen Hydrated Specimens, A. Osanna, C. Jacobsen, A. Kalinovsky, J. Kirz, J. Maser, S. Wang

Scanning Microscopy

X-ray microscopes provide higher resolution than visible light microscopes. Wet, biological materials with a water thickness of up to about 10 μm can be imaged with good contrast using soft X-rays with wavelengths between the oxygen and carbon absorption edges (at 24 and 43 Å). The Stony Brook group has developed and operates a scanning transmission X-ray microscope (STXM) at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory. The microscope is used for imaging with a current resolution of 50 nm, and for elemental and chemical state mapping.

Radiation damage imposes a significant limitation upon high resolution X-ray …


Issues Concerning The Eradication Or Establishment And Biological Control Of The Mediterranean Fruit Fly, Ceratitis Capitata(Wiedemann) (Diptera: Tephritidae), In California, David H. Headrick, Richard D. Goeden Jun 1996

Issues Concerning The Eradication Or Establishment And Biological Control Of The Mediterranean Fruit Fly, Ceratitis Capitata(Wiedemann) (Diptera: Tephritidae), In California, David H. Headrick, Richard D. Goeden

Horticulture and Crop Science

Classical biological control is suggested as a tool worth developing now for possible future use in the integrated pest management of the Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann), in California. Three factors that impact broadly on developing and implementing such a biological control program are: (1) the question of Medfly establishment, (2) quarantine considerations, and (3) agricultural and urban concerns. Each of these factors and their combined effects must be considered when discussing biological control of Medfly in California as shaped by historical perspectives on Medfly invasions, methods of Medfly eradication, and past biological control efforts against Medfly. We …


Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood Jun 1996

Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood

Nebraska Center for Virology: Faculty Publications

Perinatal human immunodeficiency virus type 1 (HIV-1) infections cause a broad spectrum of clinical disease and are variable in both the age of the patient at onset of serious disease and the progression of the clinical course. Heterozygotic perinatally infected twins with a marked difference in their clinical courses were monitored during the first 2 years of life. Twin B, the second-born twin, developed AIDS by 6 months of age and died at 22 months of age, while twin A remained minimally symptomatic through the first 2 years. Sequential blood specimens were obtained from the twins in order to characterize …


Reproductive Ecology, Population Genetics, And Clonal Distribution Of The Narrow Endemic: Mirabilis Macfarlanei (Nyctaginaceae), Jennifer L. Barnes May 1996

Reproductive Ecology, Population Genetics, And Clonal Distribution Of The Narrow Endemic: Mirabilis Macfarlanei (Nyctaginaceae), Jennifer L. Barnes

Biology

I examined the reproductive biology and population genetics of the narrow endemic, Mirabilis macfarlanei (Nyctaginaceae) Constance and Rollins, from the Snake and Salmon Rivers in Idaho and Oregon. The results of this study provide further evidence for the proposed effects of rarity on plant reproductive systems and population genetics. Breeding system results indicated that M. macfarlanei is self-compatible, but requires a pollen vector for fertilization. Seed set was not pollen limited, but may be resource limited during others. The major floral visitors were long-tongued bees such as Anthophora spp. and Bombus spp., unlike other species of Mirabilis, which are …


Imaging Molecular Structure Of Channels And Receptors With An Atomic Force Microscope, Ratneshwar Lal Apr 1996

Imaging Molecular Structure Of Channels And Receptors With An Atomic Force Microscope, Ratneshwar Lal

Scanning Microscopy

Biological membranes contain specialized protein macromolecules such as channels, pumps and receptors. Physiologically, membranes and their constituent macromolecules are the interface surfaces toward which most of the regulatory biochemical and other signals are directed. Yet very little is known about these surfaces. The structure of biological membranes has been analyzed primarily using imaging techniques that are limited in their resolution of surface topology. An atomic force microscope (AFM) developed by Binnig, Quate and Gerber, can image molecular structures on specimen surfaces with subnanometer resolution, under diverse environmental conditions. Also, AFM can manipulate surfaces with molecular precision: it can nanodissect, translocate, …


A Survey Of Small Terrestrial Mammals In The Forests Of The Tennessee River Gorge, Andrea Szymczak Apr 1996

A Survey Of Small Terrestrial Mammals In The Forests Of The Tennessee River Gorge, Andrea Szymczak

Honors Theses

In 1995, a survey of small, terrestrial mammals in the Tennessee River Gorge was undertaken.These mammals were collected by using pitfall traps in three different sites of the gorge. A total of twenty-six specimens representing six species of mammals was collected. The majority of specimens collected were long-tailed shrews.Each specimen was deposited in the Natural History Museum at the University of Tennessee at Chattanooga.


The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson Jan 1996

The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson

Chemistry Faculty Publications

The major lipooligosaccharides of the sexually transmitted pathogen Haemophilus ducreyi 35000 have been previously found to terminate in N-acetyllactosamine and sialyl-N-acetyllactosamine, Neu5Ac alpha 2-->3Gal beta 1-->4GlcNAc (W. Melaugh, N. J. Phillips, A. A. Campagnari, M. V. Tullius, and B. W. Gibson, Biochemistry 33: 13070-13078, 1994). In this study, mass spectrometry and composition analyses have shown that the lipooligosaccharides from three other H. ducreyi strains also contain N-acetyllactosamine and are highly sialylated (approximately 30 to 50%), although one African strain was found to contain neither of these structural features.


Grouse News 11-20 (1996-2000), World Pheasant Association International, Diana Lovel Jan 1996

Grouse News 11-20 (1996-2000), World Pheasant Association International, Diana Lovel

Galliformes Specialist Group and Affiliated Societies: Newsletters

Issue 11 (June 1996)

Editorial, Diana Lovel

Diary of David and Margaret's visit to the Pyrenees June 19-28, 1995

Adaptability of gamebirds, David Jenkins

Pheasants and grouse, Matt Ridley

Letter to the editor, Tim Lovel

Grouse Group founded, Rudi Suchant

Hybrids between capercaillie and black grouse and their characteristics, Jan Porkert

Does the occurrence of capercaillie-black grouse hybrids in Øvre Landvik, southern Norway signalize the coming extinction of capercaillies, as it did in Ostsudeten in the Czech Republic? Jan Porkert in cooperation with Arne Flor

Review of Naturschutz report

The effect of matrix on the occurrence of hazel grouse in …


The Texture Of Surficial Sediments In Central Long Island Sound Off Milford, Connecticut., Roman Zajac, Larry J. Poppe, B B. Taylor, Dann Blackwood, Ralph S. Lewis, Mary L. Digiacomo-Cohen Jan 1996

The Texture Of Surficial Sediments In Central Long Island Sound Off Milford, Connecticut., Roman Zajac, Larry J. Poppe, B B. Taylor, Dann Blackwood, Ralph S. Lewis, Mary L. Digiacomo-Cohen

Biology and Environmental Science Faculty Publications

The purpose of this study was to determine the grain-size distributions and associated statistical parameters of the surficial sediment samples from central Long Island Sound off Milford, Connecticut. These grain-size data, which help to ground-truth a pre-existent sidescan sonar survey (Poppe and others, 1995a; Twichell and others, in press), will eventually be used to describe the sedimentary processes active in this portion of central Long Island Sound. Other potential uses for these textural data include benthic biologic studies that evaluate faunal distributions and relate them to habitats (Zajac and others, 1995), and geochemical studies involving the distribution, transport and deposition …


The Texture Of Surficial Sediments In Western Long Island Sound Off The Norwalk Islands, Connecticut, Roman Zajac, Larry J. Poppe, B. B. Taylor, Dann Blackwood, A. E. Harmon Jan 1996

The Texture Of Surficial Sediments In Western Long Island Sound Off The Norwalk Islands, Connecticut, Roman Zajac, Larry J. Poppe, B. B. Taylor, Dann Blackwood, A. E. Harmon

Biology and Environmental Science Faculty Publications

Grain-size analyses were performed on 69 samples from western Long Island Sound. The relative grain-size frequency distributions and related statistics are reported herein. Descriptions of the benthic character from video tapes and still camera photographs of the bottom at these stations, and 33 others, are also presented. The southern and eastern parts of the study area are dominated by poorly sorted clayey silts that have nearly symmetrical distributions. Gravelly sediments are prevalent in the shallow northwestern part of the study area, but are also present in central part of the study area. Bands of sand, silty sand, and sand-silt-clay occur …


Using Confocal Microscopy In The Study Of Plant Structure And Development, Mark P. Running, Elliot M. Meyerowitz Jan 1996

Using Confocal Microscopy In The Study Of Plant Structure And Development, Mark P. Running, Elliot M. Meyerowitz

Aliso: A Journal of Systematic and Floristic Botany

The widespread application of confocal laser scanning microscopy has revolutionized biological imaging. We have developed a protocol for using confocal microscopy to examine the development of wild type and mutant Arabidopsis thaliana, overcoming the technical difficulties associated with examining whole-mounted plant tissue. This allowed us to rapidly determine the underlying cellular defects that lead to the morphological changes visible in several mutants, and has led to a greater understanding of the mechanisms involved in the control of floral organ number.


Spring 1996, Nsu Oceanographic Center Jan 1996

Spring 1996, Nsu Oceanographic Center

Currents

No abstract provided.


An Annotated Checklist Of The Spiders Of Northwestern Iowa And The Loess Hills Of Western Iowa, Barbara J. Abraham Jan 1996

An Annotated Checklist Of The Spiders Of Northwestern Iowa And The Loess Hills Of Western Iowa, Barbara J. Abraham

Journal of the Iowa Academy of Science: JIAS

Spiders were collected by the author from various habitats in 16 counties of northwestern Iowa and the loess hills of western Iowa during the summers of 1985 and 1990-1992. Additional donated specimens from the same region in 1981and1989 were identified by the author. Twenty-three families, 92 genera and 184 species have been identified.


A Review Of The Nearctic Species Of The Thrips-Attacking Genus Ceranisus Walker (Hymenoptera: Eulophidae), S. V. Triapitsyn, David H. Headrick Dec 1995

A Review Of The Nearctic Species Of The Thrips-Attacking Genus Ceranisus Walker (Hymenoptera: Eulophidae), S. V. Triapitsyn, David H. Headrick

Horticulture and Crop Science

The thrips-attacking Eulophidae (subfamily Entedoninae) known from the Nearctic region are reviewed. One new species, Ceranisus loomansi, is described. Four other species of Ceranisus are redescribed and illustrated based mainly on a study of their type specimens as well as on additional material from Arizona, California, Hawaii, Mississippi and Japan. Lectotypes are designated for Ceranisus americensis (Girault), C. nubilipennis (Williams) and C. russelli (Crawford). A key to eight species belonging to four entedonine thrips-attacking genera is given, and host associations are indicated for those species.


Flea News 51 (December 1995), Robert E. Lewis Dec 1995

Flea News 51 (December 1995), Robert E. Lewis

Flea News

Obituaries:George MacKenzie Dunnet (April 19, 1928-September 11, 1995); William Livingston Jellison (January 28, 1906-November 7, 1995)

Miscellanea

Siphonaptera literatue


Wpa News 49 (1995), World Pheasant Association Nov 1995

Wpa News 49 (1995), World Pheasant Association

Galliformes Specialist Group and Affiliated Societies: Newsletters

WPA News (November 1995), number 49

Published by the World Pheasant Association


Atomic Force Microscopy Of Nucleoprotein Complexes, Y. L. Lyubchenko, B. L. Jacobs, S. M. Lindsay, A. Stasiak Sep 1995

Atomic Force Microscopy Of Nucleoprotein Complexes, Y. L. Lyubchenko, B. L. Jacobs, S. M. Lindsay, A. Stasiak

Scanning Microscopy

Recent data on the AFM studies of nucleoprotein complexes of different types are reviewed in this paper. The first section describes the progress in the sample preparation methods for AFM studies of nucleic acids and nucleoprotein complexes. The second part of this paper reviews AFM data on studies of complexes of DNA with regulatory proteins. These studies include two different types of DNA distortion induced by proteins binding: local bending of DNA at sites of protein binding and formation of large loops due to protein-protein interactions between molecules bound to distant sites along the DNA molecules (DNA looping). The prospects …


Phylogenetic Diversity Of The Bacterial Community From A Microbial Mat At An Active, Hydrothermal Vent System, Loihi Seamount, Hawaii, Craig L. Moyer, Fred C. Dobbs, David M. Karl Apr 1995

Phylogenetic Diversity Of The Bacterial Community From A Microbial Mat At An Active, Hydrothermal Vent System, Loihi Seamount, Hawaii, Craig L. Moyer, Fred C. Dobbs, David M. Karl

OES Faculty Publications

The phylogenetic diversity of small-subunit rRNA genes associated,vith the domain Bacteria was examined (by using previously defined operational taxonomic units [C. L. Moyer, F. C. Dobbs, and D. M. Karl, Appl. Environ. Microbiol. 60:871-879, 1994]; those for Pele's Vents Bacteria are hereafter abbreviated PVB OTUs) with samples from a microbial mat at an active, deep-sea hydrothermal vent system. A cluster of phylogenetically related PVB OTUs (OTUs 2, 3, 6, and 8) was closely affiliated with Thiovulum sp. contained within the epsilon subclass of the class Proteobacteria and accounted for 60.5% of the small-subunit rRNA bacterial clone library from Pele's Vents. …


An Improved Method For Chemical Devitellinization Of X-Gal Stained Drosophila Embryos, Amit Singh, Madhuri Kango-Singh, P. Sinha Feb 1995

An Improved Method For Chemical Devitellinization Of X-Gal Stained Drosophila Embryos, Amit Singh, Madhuri Kango-Singh, P. Sinha

Biology Faculty Publications

In Drosophila developmental biological studies, X-gal staining is commonly employed to study the spatio-temporal expression of the lacZ reporter gene in the transformed flies or their embryos. Study of the lacZ pattern in embryos often suffers from the lack of an efficient and high yieldirrg technique for devitellinization of X-gal stained embryos. Devitellinization techniques employed during antibody staining, in situ hybridization or embryonic cuticular preparations generally do not give satisfactory results when used for similar purpose in X-gal stained embryos. This results in the flaky appearance of the blue stain. We present here an improved chemical devitellinization technique which gives …


Biological Processes: Relationships Between Earthworms And Soil Temperature, Edwin C. Berry, Jerry K. Radke Jan 1995

Biological Processes: Relationships Between Earthworms And Soil Temperature, Edwin C. Berry, Jerry K. Radke

Journal of the Minnesota Academy of Science

Soil fauna play important roles in many soil processes and conditions which relate to agricultural systems. Earthworms are credited with enhancing soil fertility and soil physical properties by their feeding and burrowing activities. Most research on earthworms has focused on the warmer seasons of the year and relatively little is known about earthworm activity and survival during the portion of the year with frozen soils. Earthworms may survive winter by acclimatization, aestivation, or by burrowing to deeper depths where the soil is not frozen. More research is needed on the fate of earthworms in frozen soils. Suggested research areas include: …


Management Of The Omani Abalone Haliotis Mariae: An Integrated Policy, Kadhim M. Al-Bahrani Jan 1995

Management Of The Omani Abalone Haliotis Mariae: An Integrated Policy, Kadhim M. Al-Bahrani

Marine Affairs Theses and Major Papers

The Sultanate of Oman is a small coastal nation with a maritime history, regional trade and fisheries exploitation. Among those fishery industries is Oman's coastal abalone fishery, which command the highest prices per unit of weight among the other marine living resources. This study analyzes the fishery's biological aspects, structure, socioeconomic, policies, and management practices in an attempt to provide an understanding of the prime parameters, that in turn could be utilized for sound management purposes. it also provides a description of an integrated development and management policy for the abalone fishery. Finally, it is hoped that this research will …


The Principles Of Proton Probe Microanalysis In Biology, G. J. F. Legge, M. Cholewa Dec 1994

The Principles Of Proton Probe Microanalysis In Biology, G. J. F. Legge, M. Cholewa

Scanning Microscopy

The proton microprobe, more correctly described as an ion microprobe which operates at MeV energies, complements its parent instrument the electron microprobe. This paper compares the basic principles and performance of the two instruments and relates the evolution of biological analysis on such ion microprobes to that on electron microprobes, covering the development of sample handling techniques and of data handling techniques and comparing beam damage studies. The paper describes the variety of techniques available to the ion microprobe - the initial techniques of Energy Dispersive X-ray analysis, Rutherford Back Scattering and Nuclear Reaction Analysis and the rapid evolution of …


Taxonomic Synopsis Of The Old World Asopine Genera (Heteroptera: Pentatomidae ), Donald B. Thomas Sep 1994

Taxonomic Synopsis Of The Old World Asopine Genera (Heteroptera: Pentatomidae ), Donald B. Thomas

Insecta Mundi

The subfamily Asopinae of the stinkbug family Pentatomidae is revised for the Old World with a key to the genera and a review of the species with nomenclatural changes. The genus Tahitocoris is removed from the Asopinae and placed tentatively with the Podopinae. The genus Breddiniella is reduced to a synonym of Cazira. The genus Incitatus is reduced to a synonym of Martinina. The genus Platynopus is divided into three genera by the restriction of Platynopus to include only five Indo- Pacific species; the elevation of the subgenus Montrouzieriellus to the level of full genus, and the erection …


The Effect Of Climate And Spittlebug (Aeneolamia Albofasciata) On Buffelgrass (Cenchrus Ciliaris L.) Productivity In The Sonoran Desert, Martha H. Martin-Rivera May 1994

The Effect Of Climate And Spittlebug (Aeneolamia Albofasciata) On Buffelgrass (Cenchrus Ciliaris L.) Productivity In The Sonoran Desert, Martha H. Martin-Rivera

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I conducted field studies during 1984-1988 to determine how (1) precipitation amount and distribution affect buffelgrass [Cenchrus ciliaris L. (Link) l productivity, (2) summer rainfall amount and distribution and temperature influenced the spittlebug (Aeneolamia albofasciata Lalleman) life cycle, and (3) summer burning affects spittlebug densities and buffelgrass productivity.

Experiment I was conducted from 1985 through 1988. Forage samples collected at 15-day intervals were separated into live, recent-dead standing, old-dead standing, and litter. There was a positive relationship between the summer precipitation and the live biomass. Recent-dead standing and old-dead standing decomposed during the summer, fall, or spring.

Experiment …


Quantitative Dark-Field Mass Analysis Of Ultrathin Cryosections In The Field-Emission Scanning Transmission Electron Microscope, S. Brian Andrews, Roger A. Buchanan, Richard D. Leapman Apr 1994

Quantitative Dark-Field Mass Analysis Of Ultrathin Cryosections In The Field-Emission Scanning Transmission Electron Microscope, S. Brian Andrews, Roger A. Buchanan, Richard D. Leapman

Scanning Microscopy

The availability of a cryotransfer stage, highly efficient electron energy loss spectrometers, and ultrathin-window energy-dispersive x-ray spectrometers for the VG Microscopes HB501 field-emission scanning transmission electron microscope (STEM) provides this instrument with the potential for high resolution biological microanalysis. Recent technical advances offer cryosections that are thin enough to take advantage of the analytical capabilities of this microscope. This paper first discusses the quantitative characterization of freeze-dried, ultrathin cryosections of directly frozen liver and brain by low-dose dark-field STEM imaging. Such images reveal high-quality sections with good structural detail, mainly due to reduced preparation artifacts and electron beam damage. These …


Analysis Of High Quality Monatomic Chromium Films Used In Biological High Resolution Scanning Electron Microscopy, Robert P. Apkarian Apr 1994

Analysis Of High Quality Monatomic Chromium Films Used In Biological High Resolution Scanning Electron Microscopy, Robert P. Apkarian

Scanning Microscopy

During the recent employment of field emission (FE) in-lens scanning electron microscopes (SEMs), refractory metal deposition technology has co-evolved to provide enhanced contrast of 1-10 nm hydrocarbon based biological structures imaged at high magnifications (> 200,000 times). Pioneer development employing the Penning sputter system in a high vacuum chamber proved that imaging of chromium (Cr) coated biological specimens contained enriched secondary electron (SE)-(I) contrasts. Single nanometer size fibrillar and particulate ectodomains within the context of complex biological membranes were accurately imaged without significant enlargement using the high resolution SE-I mode (HRSEM). This paper reports the transmission electron microscopy (TEM) testing …


The Preparation Of Cultured Cells For X-Ray Microanalysis, Alice Warley Apr 1994

The Preparation Of Cultured Cells For X-Ray Microanalysis, Alice Warley

Scanning Microscopy

X-ray microanalysis of cells in culture is being used increasingly for the study of relationships between element (ion) content and cell function. There is, however, no one single method which can be used for the preparation of all different cell types for study by microanalysis. Cells in suspension are usually concentrated by centrifugation, before cryofixation, cryosectioning, and freeze drying. On the other hand cells grown as monolayers are more often studied as whole cell mounts, which are washed to remove the external medium before cryofixation and freeze drying. The alternative approach, sectioning of cell monolayers is rarely used. Some of …


Neotype Designations For The Type Species Of Phidippus (Araneae: Salticidae), G. B. Edwards Mar 1994

Neotype Designations For The Type Species Of Phidippus (Araneae: Salticidae), G. B. Edwards

Insecta Mundi

Neotypes are designated for Attus audax Hentz and Salticus variegatus Lucas in order to establish the identity of these species to facilitate a ruling on the proper name of the type species of the genus Phidippus by the International Commission of Zoological Nomenclature.


Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority Feb 1994

Study Of Existing Information Concerning Water Quality Within Lake Mead, Vicki Scharnhorst, Southern Nevada Water Authority

Publications (WR)

The purpose of Task 010A15M of the Southern Nevada Water Authority (SNWA) Treatment and Transmission Facility (TTF) contract is to conduct a study of existing information concerning water quality within Lake Mead and identify additional water quality studies that are needed to supplement existing data. The objective of this task is not to discuss treatability of the raw water source; this is addressed by Task 010A18M, "Define Water Treatment Requirements." In addition, a narrative on the effect of pending Safe Drinking Water Act amendments and a determination of treated water quality goals is included in Task 010A16M, "Review Safe Drinking …