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Public Policy On The Introduction Of Genetically Engineered Microorganisms, Anne K. Vidaver Jan 1989

Public Policy On The Introduction Of Genetically Engineered Microorganisms, Anne K. Vidaver

Journal of the Iowa Academy of Science: JIAS

This presentation raises questions of research needs and issues. Underlying assumptions are that only beneficial or useful microorganisms will be "released"; that extensive laboratory and contained experiments will have been done prior to introduction and live microorganisms can be confined within the areas of introduction. Evidence to support these assertions will be presented. Critical needs for progress in this area include: 1) Recognition that the nature of the product introduced into the environment is of primary significance, not how the organism was genetically altered or modified. 2) Recognition that microorganisms are introduced into the environment as part of our daily …


Human Impacts To Minnesota Wetlands, Carol A. Johnston Jan 1989

Human Impacts To Minnesota Wetlands, Carol A. Johnston

Journal of the Minnesota Academy of Science

ABSTRACT-Minnesota's 3.6 million ha of wetlands have been impacted by a variety of human activities, including agricultural drainage, urbanization, water control, and nonpoint source pollution. More than half of Minnesota's wetlands have been destroyed since the first European settlers arrived, an average loss of about 35,600 ha/yr. Drainage for agriculture is the major cause of wetland loss in Minnesota, particularly in southern Minnesota and the Red River Valley. In addition to impacting wetlands directly, wetland drainage affects downstream areas by increasing flood flows, and releasing sediment and nutrients. Urban development and highway construction affect a smaller proportion of Minnesota's wetlands, …


Rottnest Island : A Reference List, Jennifer Browne Jan 1989

Rottnest Island : A Reference List, Jennifer Browne

Research outputs pre 2011

No abstract provided.


Potassium Nutrition Of Pastures On The Sandplain Soils Of Western Australia., Noeleen Edwards, M. Thomas Jan 1989

Potassium Nutrition Of Pastures On The Sandplain Soils Of Western Australia., Noeleen Edwards, M. Thomas

Experimental Summaries - Plant Research

Project: Potassium nutrition of pastures on the sandplain soils of Western Australia.

Determine the factors affecting the fate of native and applied potassium on sandplain soils.
Define current and residual response curve parameters for potassium applications. Develop recommendations for the economic management of soil potassium levels.

Trial 88B46, 88TS69, 89KO26

Maintenance application rates of potassium on sandplain soils.

Location: Badgingarra Research Station, new block, North Eneabba, Kojaneerup Research Block.

Trial 89BA24

Residual value of potassium on sandplain soils.

Location: Badgingarra Research Station

Trial 89MT46,

Potassium requirements of sub clover.

Location: Mt Barker Research Station.

Project: Potassium nutrition of lupins on …


Barley Agronomy Experiments., K. L. Young Jan 1989

Barley Agronomy Experiments., K. L. Young

Experimental Summaries - Plant Research

Trial 89E1, 89SG1, 89MT3

Barley variety x time of sowing trials.

Location: Esperance Downs Research Station, Salmon Gums Research Station, Mt Barker Research Station

To determine the optimum time of ear emergence for barley varieties which vary in maturity.

Trial 89ES2

Location: Melijinup Field Station

Barley variety x time of sowing trials

1. Assess the effect of aphids on the yield of barley at a range of sowing times.

2. Determine the optimum time of ear emergence for barley varieties which vary in maturity.

Trial 89E6

The effect of aphids on the yield of barley

Location: Esperance Downs Research Station. …


Santa Clara Magazine, Volume 31 Number 1, Fall 1988, Santa Clara University Oct 1988

Santa Clara Magazine, Volume 31 Number 1, Fall 1988, Santa Clara University

Santa Clara Magazine

12 - MY CHINA YEAR Cathy Morrissey '85 guides us through her year in China, teaching English as a second language in Handan.

19 - IT PAYS TO LET YOUR KID RUN WILD The story of a remarkable relationship between a Japanese firm and Michael Franz '75.

21 - THE REWAK YEARS Alumna-journalist Jeanne Huber describes the way Santa Clara grew during the Rewak administration.

26 - THE DEGNAN WAY How a respected English professor turns undergraduates into professional writers.


The Effect Of Preozonation On The Anaerobic Biodegradability Of Resistant Phenolic Compounds, Yi-Tin Wang, Pin-Chieh Pai, James L. Latchew Aug 1988

The Effect Of Preozonation On The Anaerobic Biodegradability Of Resistant Phenolic Compounds, Yi-Tin Wang, Pin-Chieh Pai, James L. Latchew

KWRRI Research Reports

Ozone pretreatment studies of four model phenolic compounds were conducted to evaluate the effects of ozonation on the anaerobic biodegradability and toxicity of these compounds. Two types of batch studies, the Biochemical Methane Potential (BMP) and the Anaerobic Toxicity Assay (ATA), were performed on samples ozonated upon phenol, o-cresol, 2,5-dichlorophenol, and 2,4-dinitrophenol.

Experimental results showed that toxic and refractory phenolic compounds were converted to methane gas by means of preozonation. In general, the biodegradable fraction of the oxidation products increased as the ozone dose was increased. However, ozonation to achieve at least 60% COD reduction was necessary to faciliate methane …


Analysis Of Ferredoxin And Flavodoxin In Anabaena And Trichodesmium Using Fast Protein Liquid Chromatography, Karen Lorraine Jones Jul 1988

Analysis Of Ferredoxin And Flavodoxin In Anabaena And Trichodesmium Using Fast Protein Liquid Chromatography, Karen Lorraine Jones

Dissertations and Theses

Iron is an essential nutrient for growth of photosynthetic microorganisms such as cyanobacteria and algae. Iron is required for proteins involved in the important processes of carbon and nitrogen assimilation. Low concentrations of iron in cultures or natural waters can lead to iron limitation which affects many aspects of algal metabolism. In natural waters, iron limitation can have effects on the patterns and rates of primary productivity.

The cellular content of certain proteins can be affected by media iron concentrations. Methods have been used that assay components of the cell as an indirect measure of iron nutritional status. For example, …


Miscellaneous Production 23/87 - Animal Production In The Spinifex And Shrubland Regions Of Western Australia, D. Burnside Jul 1988

Miscellaneous Production 23/87 - Animal Production In The Spinifex And Shrubland Regions Of Western Australia, D. Burnside

Animal production and livestock published reports

The role of the Rangeland Management Branch is to promote the sustained economic use of the rangeland resource. It provides research and extension services to the pastoral industry, provides advice on the condition of the range resource to Government and provides technical information on rangelands to other rangeland managers. A principal objective to be met in fulfilling that role is the development and promotion of economically efficient place systems that conserve the rangeland resource. At the inaugural Pastoral Soil Conservation Districts Conference in Meekatharra in May 1987, pastoralist delegates emphasized the importance of achieving that objective within the various soil …


Microbial Food Resources Of The Macrofaunal-Deposit Feeder Ptychodera Bahamensis (Hemichordata: Enteropneusta), Fred C. Dobbs, James B. Guckert Jun 1988

Microbial Food Resources Of The Macrofaunal-Deposit Feeder Ptychodera Bahamensis (Hemichordata: Enteropneusta), Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Biochemical and traditional analyses were used to characterize the microbial food resources and digestive efficiency of Ptychodera bahamensis, an enteropneust hemichordate. Sediment was collected from freshly extruded fecal casts and adjacent feeding depressions. There were no significant differences between casts and depressions in median grain size, percent silt-clay, density of total meiofauna and of nematodes, and concentrations of chlorophyll a and phaeophytin. Nematodes in casts had a median diameter greater than those in depressions. Measures of total, viable microbial biomass were 30% (total phospholipid, ester-linked fatty acids) and 49% (extractible phospholipid phosphate) lower in casts. Concentrations of 33 fatty …


Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard May 1988

Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The teratogenic potency of retinoid analogs was determined in Syrian hamsters and compared to the teratogenic potency of all-trans-retinoic acid (all-trans-RA, ED50 = 10.5 mg/kg). A total of 15 analogs having variations in the cyclohexene ring were evaluated following various amounts of single oral doses on day 8 of gestation. Retinoids containing a five- or six-membered ring were as teratogenic as all-trans-RA, provided they had sufficient lipophilic substituents on the ring. The same pattern emerged for retinoids that had six-membered aromatic ring substitution for the natural cyclohexene ring of vitamin A. Incorporation of a supplementary …


A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz May 1988

A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Field and laboratory studies were conducted to develop a model of energy expenditure in a population of white-tailed jackrabbits (Lepus townsendii). Field work in southwestern Wyoming during 1985-87 showed that the breeding season commenced at snowmelt and ceased during late- July drought. Adult females reproduced relatively synchronously and produced a mean of three litters annually. Greatest fetal production occurred in the second litter period. Collections indicated a 1:1 sex ratio, few jackrabbits >2 years-old, and a density of 7 animals / km2 in the population. Postnatal growth was sigmoidal, culminating in heavier adult females than males. Using …


Use Of 52Cr For The Quantitative Determination Of Red Cell Volume, Claude Michael Hanbury Apr 1988

Use Of 52Cr For The Quantitative Determination Of Red Cell Volume, Claude Michael Hanbury

Chemistry & Biochemistry Theses & Dissertations

Chromium-52 has recently been suggested for use as a new agent to label red cells for the in vivo quantitation of red cell volume (1). In this paper, the development and validation of a routine 52cr labeling procedure is described.

The accuracy, precision, and detection limits of chromium analysis by Zeeman effect atomic absorption spectroscopy was evaluated in the concentration range of 1 - 10 ug Cr/L.

Red cell chromium uptake was evaluated as a function of time, temperature, and concentration. Red cells labeled with a 2.5 mg/L chromium solution for 30 minutes at room temperature exhibited optimal label …


Prolonged Seed Handling Time Deters Red-Winged Blackbirds Feeding On Rice Seed, Dennis Daneke, David G. Decker Mar 1988

Prolonged Seed Handling Time Deters Red-Winged Blackbirds Feeding On Rice Seed, Dennis Daneke, David G. Decker

Vertebrate Pest Conference Proceedings: 13th (1988)

Theoretical concepts from foraging ecology were studied to identify elements of blackbird foraging strategies that may be manipulated to deter blackbirds feeding on rice. Seed-handling time was identified as one such vulnerable element. Consequently, we developed seed coatings for rice that increased handling time per seed, allowed a satisfactory germination rate, and persisted for several days postplanting. Test coats included hydrophilic binders with several starches, clays, plaster of paris and chemical grout in various combinations. Consistent repellency was achieved in feeding trials with captive red-winged blackbirds.


Characteristics Of Bird-Resistance In Agricultural Crops , Roger W. Bullard Mar 1988

Characteristics Of Bird-Resistance In Agricultural Crops , Roger W. Bullard

Vertebrate Pest Conference Proceedings: 13th (1988)

The use of biochemical or morphological genetic traits in a crop to protect ripening seeds or grain from bird damage remains a promising tool under certain situations. Research on bird-resistance in crops has focused on grain sorghum, corn, sunflower and rice. This crop protection method involves feeding behavior of granivorous birds and its effectiveness depends on the availability of preferred alternate foods. That is, bird-resistant traits provide protection to the crop when other food choices are readily available; however, when alternate food is scarce or high bird populations create serious feeding competition, they are less effective. Several practical factors (i.e., …


Evaluating Hay Quality, William C. Templeton Jr. Feb 1988

Evaluating Hay Quality, William C. Templeton Jr.

Kentucky Alfalfa and Stored Forage Conference

One of the frustrations to nutritionists interested in the feeding value of roughage has been that with all their book knowledge and technical aids no dependable scheme they could devise would consistently rank forages in feeding value, while the dumb ruminant animal could unerringly detect differences in their nutritive values.
-E. W. Crampton, 1965


Evaluation Of New Pasture Legume Species In Terms Of Summer Feeding Value And Effects On Wool Production., Tess Casson Jan 1988

Evaluation Of New Pasture Legume Species In Terms Of Summer Feeding Value And Effects On Wool Production., Tess Casson

Experimental Summaries - Plant Research

Trial 86KA71

Location: Private farm 'Monalta' - south-east of Katanning.

As outlined by S. Flecker in the 1987 summary for this trial, the expected result of the research is that the feeding value of burr medic pastures will be greater than the feeding value of sub. clover and barrel medic pasture, particularly over the dry summer/autumn period.


An Inventory And Condition Survey Of Rangelands In The Ashburton River Catchment, Western Australia, A A. Mitchell, A L. Payne, W F. Holman Jan 1988

An Inventory And Condition Survey Of Rangelands In The Ashburton River Catchment, Western Australia, A A. Mitchell, A L. Payne, W F. Holman

Technical Bulletins

The inventory and condition survey of rangelands in the Ashburton River catchment, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1976 and 1978, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed …


13.3.2. Initial Considerations For Sampling Wetland Invertebrates, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.3.2. Initial Considerations For Sampling Wetland Invertebrates, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

As the importance of invertebrates to waterbird nutrition and detrital processing has become increasingly evident, the need for effective and efficient invertebrate sampling has grown. Identification of invertebrate responses to management requires sampling and selection of appropriate sampling equipment. Goals must be established according to qualitative or quantitative needs, organism characteristics, and wetland types. Management objectives often can be met by sampling specific invertebrates to index the effect of management rather than through long-term studies requiring large sample sizes and intensive effort. Certain wetland and invertebrate characteristics that should be considered when initiating invertebrate sampling are described below.


13.4.1. Considerations Of Community Characteristics For Sampling Vegetation, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.4.1. Considerations Of Community Characteristics For Sampling Vegetation, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

Wetland managers often monitor marsh vegetation to determine if management goals have been met and expenditures justified. Vegetation can be monitored using indices that identify plant composition, trends in vegetative changes, or rough estimates of food production. Development of vegetation sampling protocol requires careful assessment of management goals in relation to benefits received from sampling efforts. Assessing the results of manipulations has direct management implications, whereas detailed studies that emphasize plant life histories or basic ecological investigations have less direct value. Information on plant community characteristics that will enable managers to match sampling techniques with refuge needs and the constraints …


13.4.10. Control Of Willow And Cottonwood Seedlings In Herbaceous Wetlands, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.4.10. Control Of Willow And Cottonwood Seedlings In Herbaceous Wetlands, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

Willow and cottonwood are common species in forested wetlands and occur throughout most riparian and floodplain habitats of North America. These woody species are especially common in early successional stands where seasonal flooding occurs regularly. Cottonwood and willow are often considered problem plants, because they rapidly invade wetlands dominated by herbaceous flora and can form dense, extensive stands. The shade created by these species eliminates herbaceous undergrowth, and once the sapling stage is reached, cottonwoods and willows are difficult to eradicate. Control of these species can be costly and varies considerably with latitude.


Production From The Management Of Burr Medic Pastures, C W. Thorn Jan 1988

Production From The Management Of Burr Medic Pastures, C W. Thorn

Journal of the Department of Agriculture, Western Australia, Series 4

No abstract provided.


The Probe, Issue 79 - January 1988 Jan 1988

The Probe, Issue 79 - January 1988

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
JANUARY 1988
Animal Traps – Kinder Than Nature
The Pesticide Pipeline
APHIS Activity Report
Letters to Ye Ed
The Fur Industry


13.2.1. Waterfowl Use Of Wetland Complexes, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.2.1. Waterfowl Use Of Wetland Complexes, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

Waterfowl are a diverse group of birds that have widely divergent requirements for survival and recruitment. Whistling-ducks, geese, and swans (Anserinae) and ducks (Anatinae) have contrasting life history requirements.

Several goose populations have expanded greatly despite extensive continental wetland losses and degradation. Most expanding populations nest in arctic areas where modifications or disturbance of nesting habitats have been minimal. These grazers often find suitable migratory and wintering habitats in terrestrial or agricultural environments. In contrast, ducks are less terrestrial and populations are influenced more by wetland characteristics, such as quality, total area of wetland basins, and size and configuration of …


13.3.1. Invertebrate Response To Wetland Management, Leigh H. Fredrickson Jan 1988

13.3.1. Invertebrate Response To Wetland Management, Leigh H. Fredrickson

Waterfowl Management Handbook

By gaining greater understanding and appreciation of wetland environments, managers have developed creative insights for waterfowl conservation. Among the most exciting new developments in the understanding of functional wetlands has been the recognition of the important roles of invertebrates in aquatic ecosystems. These roles include trophic linkage from primary production to secondary consumers such as waterfowl, packaging of specific nutritional components such as amino acids and micronutrients for vertebrate predators, and detrital processing of wetland organic material. Although specific invertebrate responses to various management techniques are not always predictable and may differ among invertebrate species, patterns related to water regimes, …


13.4.9. Preliminary Considerations For Manipulating Vegetation, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.4.9. Preliminary Considerations For Manipulating Vegetation, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

A wide diversity of plants has adapted to the dynamic nature of wetlands. The continually changing floral landscape is shaped by physical or abiotic components that include climate, fire, soil, and water. Water quantity, quality, and chemistry have a dominating influence on wetlands as do factors such as hydroperiod (period when soils are saturated) and hydrological regime. Other factors that may affect the abundance, structure, and species composition of macrophytes or robust emergents are natural grazing, disease, and interspecific plant competition.

Vegetation is important to waterfowl for producing seeds, tubers, and browse; providing nest sites; and serving as substrates for …


13.1.1. Nutritional Values Of Waterfowl Foods, Leigh H. Fredrickson, Frederic A. Reid Jan 1988

13.1.1. Nutritional Values Of Waterfowl Foods, Leigh H. Fredrickson, Frederic A. Reid

Waterfowl Management Handbook

Over 40 species of North American waterfowl use wetland habitats throughout their annual cycles. Survival, reproduction, and growth are dependent on the availability of foods that meet nutritional requirements for recurring biological events. These requirements occur among a wide variety of environmental conditions that also influence nutritional demands. Recent work on nesting waterfowl has identified the female’s general nutrient needs for egg laying and incubation. Far less is known about nutritional requirements for molt and other portions of the life cycle, particularly those during the non-breeding season. Although information on specific requirements for amino acids and micronutrients of wild birds …


Complete Waterfowl Management Handbook Jan 1988

Complete Waterfowl Management Handbook

Waterfowl Management Handbook

The North American Waterfowl Management Plan, the Service's most recent mandate for management of migratory waterfowl, and recent legislation such as the Farm Bill all underscore the need for a single source of information about the management of waterfowl and their habitat. Much of this information exists in scientific papers, unpublished reports, or has never been recorded, and thus is not readily accessible by waterfowl managers. The need for a waterfowl management handbook was originally suggested to the Office of Information Transfer by personnel in the Service's north-central region. A prototype handbook was developed in 1987 and critiqued by 38 …


Impact Of Biotechnology On Agriculture Productivity, Roger A. Kleese Jan 1988

Impact Of Biotechnology On Agriculture Productivity, Roger A. Kleese

Journal of the Iowa Academy of Science: JIAS

Biotechnology is a diverse array of technologies which today are in various stages of evolution and development. To understand them and the potential application of these technologies to agriculture, it is helpful to consider them in a historical perspective. In addition, it is important to understand the interdependence of biotechnologies on traditional, well developed technologies. The commercial development of biotechnology is more difficult than imagined even as recently as five years ago. Also, the problems being addressed generally demand a much better understanding of the physiology and biochemistry of the plant and animal systems under study. Nonetheless, there is a …


Dryland Pasture Legume Programme, C. K. Revell, G. Croker, J. Simmons, L. Heinrich Jan 1988

Dryland Pasture Legume Programme, C. K. Revell, G. Croker, J. Simmons, L. Heinrich

Experimental Summaries - Plant Research

1. Medic variety evaluation

a. Row Evaluation - 88ME122 - Merredin.
This method of assessment was used to test a range of new medic material originating from the South Australian Department of Agriculture.

b. Evaluation of burr medics on Morrel soils. - 88ME84 - Nokaning.

c. Evaluation of burr medics on Whitegum soils. 88ME85 - North Kellerberrin.

d. Evaluation of Santiago in low rainfall areas - 88ME86 - Mukinbudin.

e. Selection of early maturing M. murex. 88SC30 - Merredin.

f. Medic species evaluation - large plots. 88NO88 - Tammin.

g. Medic species evaluation - large plots. 85M43 - Merredin Research …