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Summer 1996, Nsu Oceanographic Center Jan 1996

Summer 1996, Nsu Oceanographic Center

Currents

No abstract provided.


Fish Advisories: Useful Or Difficult To Interpret?, Joanna Burger, Michael Gochfeld Jan 1996

Fish Advisories: Useful Or Difficult To Interpret?, Joanna Burger, Michael Gochfeld

RISK: Health, Safety & Environment (1990-2002)

The authors note that fish and shellfish offer significant exposure to environmental toxins but find that consumer knowledge and other factors may limit efforts to control risk in urban populations.


Temporal And Spatial Patterns In Water Chemistry, Phytoplankton Biomass And Microcrustacea In Lake Joondalup And Beenyup Swamp, Western Australia, Kimberley Upton Jan 1996

Temporal And Spatial Patterns In Water Chemistry, Phytoplankton Biomass And Microcrustacea In Lake Joondalup And Beenyup Swamp, Western Australia, Kimberley Upton

Theses : Honours

Lake Joondalup is one of the largest remaining permanent lakes of the Swan Coastal Plain. Despite increasing urbanisation, it supports highly diverse terrestrial and riparian communities, and an abundant and diverse aquatic fauna. However, like other wetlands of the Swan Coastal Plain, Lake Joondalup is increasingly threatened by eutrophication and degradation. The aims of this study were to describe the patterns in selected physical, chemical parameters, microcrustacean abundance and biomass of Daphnia carinata in Beenyup Swamp and the adjacent sections of Lake Joondalup; to identify the likely factors determining the patterns of phytoplankton biomass in these wetlands; and to suggest …


Factors Affecting Attwater's Prairie-Chicken Decline On The Attwater Prairie Chicken, Michael E. Morrow, Robert S. Adamcik, Jenny D. Friday, Lloyd B. Mckinney Jan 1996

Factors Affecting Attwater's Prairie-Chicken Decline On The Attwater Prairie Chicken, Michael E. Morrow, Robert S. Adamcik, Jenny D. Friday, Lloyd B. Mckinney

United States Geological Survey: Staff Publications

We examined the association between changes in the number of Attwater's prairie-chicken (Tympanuchus cupido attwateri) on the Attwater Prairie Chicken National Wildlife Refuge from 1972 to 1993 and changes in refuge management practices (burning and grazing). We also examined the relationship of prairie-chicken population increases and decreases on the refuge to rainfall and off-refuge prairie-chicken populations. Burning within the prairie-chicken's core habitat on the refuge and variability in grassland structure were directly correlated (P < 0.05) with increases and declines in prairie-chicken populations. Refuge population increases and declines were inversely correlated (P < 0.1) with average April rainfall/event, May absolute departure from long-term average rainfall, May number of rainfall events, annual absolute departure of rainfall from the long-term average, and the annual number of rainfall events. Refuge population increases and declines were directly correlated (P < 0.1) with off-refuge populations, although the off- refuge population decline began 4 years earlier than on-refuge.


Small Mammal Community Structure In Restored Prairies, Kathleen A. Falout Jan 1996

Small Mammal Community Structure In Restored Prairies, Kathleen A. Falout

Masters Theses

The Illinois Department of Natural Resources currently manages approximately 4,000 hectares of natural prairie. High human impacts coupled with small patch size result in challenging management decisions for prairie conservation. The ideal restored prairie would consist of a mosaic of habitats varying in vegetation from forb-grass dominated areas to oak savannas, with concurrent stages of vegetative succession occurring across the habitats. A study was conducted at the Middle Fork State Fish and Wildlife Area located in Vermillion County, IL, to analyze small mammal diversity and community composition among three different stages of prairie restoration.

The three treatment categories were: fallow …


Effect Of Light/Dark Transition On Carbon Translocation In Eelgrass Zostera Marina Seedlings, Richard C. Zimmerman, Randall S. Alberte Jan 1996

Effect Of Light/Dark Transition On Carbon Translocation In Eelgrass Zostera Marina Seedlings, Richard C. Zimmerman, Randall S. Alberte

OES Faculty Publications

Carbon translocation in the marine macrophyte Zostera marina L. (eelgrass) was investigated to elucidate the impact of light/dark transitions on sucrose partitioning between roots and shoots. After exposure of leaves to C-14-bicarbonate, the level of C-14-labelled photoassimilates increased monotonically in both leaves and fully aerobic roots of plants maintained in the light. Accumulation of C-14 in roots and leaves ceased abruptly when plants were transferred to darkness that induced root anaerobiosis even though C-14 levels remained high in the dark-exposed leaves. Thus, translocation of C-14 photoassimilates from shoots to roots was inhibited when roots became anoxic. Anoxia induced by light …


Development And Lipid Composition Of The Harpacticoid Copepod Nitocra Spinipes Reared On Different Diets, Gregory M. Weiss, George B. Mcmanus, H. Rodger Harvey Jan 1996

Development And Lipid Composition Of The Harpacticoid Copepod Nitocra Spinipes Reared On Different Diets, Gregory M. Weiss, George B. Mcmanus, H. Rodger Harvey

OES Faculty Publications

We reared the harpacticoid copepod Nitocra spinipes on diets of bacteria, a diatom, or a macroalga, evaluating survivorship and growth in short-term (≤ 1 generation) experiments. Lipid content of the copepods and their diets was measured and used as an index of nutrition. Although growth, survivorship and lipid content of N. spinipes were significantly greater when fed the diatom, which had the highest lipid content of the 3 diets, the copepod was able to develop from egg to adult when fed a lipid- poor bacterial diet. Furthermore, this species was able to go through developmental molts without the addition of …


Bulletin No. 34: Tidal Marshes Of Long Island Sound: Ecology, History And Restoration, Glenn D. Dreyer, William A. Niering Dec 1995

Bulletin No. 34: Tidal Marshes Of Long Island Sound: Ecology, History And Restoration, Glenn D. Dreyer, William A. Niering

Bulletins

No abstract provided.


Regulation Of The Expression Of Lipogenic Enzymes By Insulin-Mimetics, Juiyu Wu Dec 1995

Regulation Of The Expression Of Lipogenic Enzymes By Insulin-Mimetics, Juiyu Wu

Masters Theses

Many researchers have shown that selenate (SeO42-) and vanadate (VO42-) have insulin-mimetic effects in certain biological processes. These mimetic effects include increasing glucose transport, regulating glycolytic enzymes, normalizing plasma glucose levels and activities of insulin regulated enzymes in diabetic rats. To clarify the functions and roles of these insulin-mimetics in different insulin-regulated metabolic pathways, the expression of the genes for glucose-6-phosphate dehydrogenase (G6PDH) and fatty acid synthase (FAS) were investigated. G6PDH is a key enzyme in the pentose phosphate pathway and is also involved in lipogenic metabolism by providing 55-70% of the NADPH utilization …


Effects Of Insulin And Insulin Mimetics On Antioxidant Enzyme Levels: In Vivo And In Vitro, Shikha Varma Dec 1995

Effects Of Insulin And Insulin Mimetics On Antioxidant Enzyme Levels: In Vivo And In Vitro, Shikha Varma

Masters Theses

Tissue antioxidation status is considered to be an important factor for elucidating the etiology of diabetes and its physiological complications. This study was aimed to determine the in vivo antioxidant enzyme levels in the altered antioxidant status of diabetic rat liver with the treatment of two potent insulin mimetics, vanadium and selenate. The direct effects of vanadate, selenate, and zinc (another insulin mimetic) on the antioxidant enzyme levels in primary rat hepatocytes in culture was also determined. Levels of superoxide dismutase (SOD), catalase (CAT) and gluthahione peroxidase (GPX) were determined in both model systems.

In the vivo model, insulin treatment …


Rodent Damage Control In No-Till Corn And Soybean Production, Ron Hines Nov 1995

Rodent Damage Control In No-Till Corn And Soybean Production, Ron Hines

Wildlife Damage Management Conference

In recent years the primary cause of reduced plant stands in no-till crops planted into heavy residue has been small eared rodents called voles (Microtus spp.). Past research has indicated that severe stand reductions (80 to 100 percent) can occur if vole populations in the field exceed 75 per hectare (30 per acre) at planting time. This vole population should be considered intense. If field scouting about 30 days prior to planting reveals at least 12 active vole colonies per hectare (five per acre) an intense population can develop, and damage control measures should be planned. Of all …


Assessment Of Gnawing Behavior Of Three Rodent Species On Automatic Speed Control Mechanism Diaphragms From Gm Automobiles, Glenn R. Dudderar, Ren-Rong Hou, Scott R. Winterstein Nov 1995

Assessment Of Gnawing Behavior Of Three Rodent Species On Automatic Speed Control Mechanism Diaphragms From Gm Automobiles, Glenn R. Dudderar, Ren-Rong Hou, Scott R. Winterstein

Wildlife Damage Management Conference

General Motors and the A C. Rochester Company, a subsidiary of General Motors (GM), has found that the rubber diaphragms on automatic speed control mechanisms (servos) were gnawed by unknown rodents. House mice (Mus musculus), Peromyscus spp., and eastern chipmunks (Tamias striatus) were used to test gnawing behavior on 4 kinds of diaphragms. Diaphragms with or without a rodent proof cure formula, which are used by GM, did not influence the gnawing of all test rodent species. Diaphragms with a lubricant (Paricin) were more attractive to gnawing by house mice than diaphragms without a lubricant. …


A Strategy For Integrating Principles And Concepts Of Wildlife Damage Control Into The School Curriculum, Thomas A. Eddy Nov 1995

A Strategy For Integrating Principles And Concepts Of Wildlife Damage Control Into The School Curriculum, Thomas A. Eddy

Wildlife Damage Management Conference

This paper reports an approach to educating today's youth concerning the importance of regulating numbers of wildlife species that threaten property, products and health. The emphases are on preparing teachers to integrate principles and concepts into the existing curricular materials, justifying control measures with ecological understandings and economic information and dealing effectively with sensitive animal rights issues. Opportunities for integration of specific wildlife damage control topics are suggested for lessons in the life sciences, social sciences, health, language arts and mathematics. Examples of conflict between groups of different opinions about the seriousness of a pest's activities or appropriateness of control …


Assessment Of Gnawing Behavior Of Three Rodent Species On Automatic Speed Control Mechanism Diaphragms From Gm Automobiles, Glenn R. Dudderar, Ren-Rong Hou, Scott R. Winterstein Nov 1995

Assessment Of Gnawing Behavior Of Three Rodent Species On Automatic Speed Control Mechanism Diaphragms From Gm Automobiles, Glenn R. Dudderar, Ren-Rong Hou, Scott R. Winterstein

Eastern Wildlife Damage Management Conference: 7th (1995)

General Motors and the A C. Rochester Company, a subsidiary of General Motors (GM), has found that the robber diaphragms on automatic speed control mechanisms (servos) were gnawed by unknown rodents. House mice (Mus musculus), Peromyscus spp., and eastern chipmunks (Tamias striatus) were used to test gnawing behavior on 4 kinds of diaphragms. Diaphragms with or without a rodent proof cure formula, which are used by GM, did not influence the gnawing of all test rodent species. Diaphragms with a lubricant (Paricin) were more attractive to gnawing by house mice than diaphragms without a lubricant. Five …


A Strategy For Integrating Principles And Concepts Of Wildlife Damage Control Into The School Curriculum, Thomas A. Eddy Nov 1995

A Strategy For Integrating Principles And Concepts Of Wildlife Damage Control Into The School Curriculum, Thomas A. Eddy

Eastern Wildlife Damage Management Conference: 7th (1995)

This paper reports an approach to educating today's youth concerning the importance of regulating numbers of wildlife species that threaten property, products and health. The emphases are on preparing teachers to integrate principles and concepts into the existing curricular materials, justifying control measures with ecological understandings and economic is information and dealing effectively with sensitive animal rights issues. Opportunities for integration of specific wildlife damage control topics are suggested for lessons in the life sciences, social sciences, health, language arts and mathematics. Examples of conflict between groups of different opinions about the seriousness of a pest's activities or appropriateness of …


Rodent Damage Control In No-Till Corn And Soybean Production, Ron Hikes Nov 1995

Rodent Damage Control In No-Till Corn And Soybean Production, Ron Hikes

Eastern Wildlife Damage Management Conference: 7th (1995)

In recent years the primary cause of reduced plant stands in no-till crops planted into heavy residue has been small eared rodents called voles (Microtus spp.). Past research has indicated that severe stand reductions (80 to 100 percent) can occur if vole populations in the field exceed 75 per hectare (30 per acre) at planting time. This vole population should be considered intense. If field scouting about 30 days prior to planting reveals at least 12 active vole colonies per hectare (five per acre) an intense population can develop, and damage control measures should be planned. Of all …


Santa Clara Magazine, Volume 37 Number 4, Fall 1995, Santa Clara University Oct 1995

Santa Clara Magazine, Volume 37 Number 4, Fall 1995, Santa Clara University

Santa Clara Magazine

8 - OF QUARKS, OBJECT IDENTIFICATION, AND PORPHYRIN MOLECULES SCU undergraduates get a taste of scientific research. By Miriam Schulman

14 - WHAT'S YOUR BOTTOM LINE? By investing in mutual funds that reflect their values, an increasing number of shareholders hope to put their money where their morals are. But can socially responsible investing really change the world? By Jeff Brazil ' 85

22 - A BIG ENOUGH UMBRELLA Tens of thousands of women from around the world gather for a unifying-albeit rainy- conference in China. Photographs By Kim Johnson ' 87

26 - THE ART OF MATHEMATICS For every …


Fish Health For Fish Farmers In Western Australia, Tina Thorne Oct 1995

Fish Health For Fish Farmers In Western Australia, Tina Thorne

Fisheries Published Reports

Disease is a departure from the normal state of health of a fish or any other animal. Diseases have no doubt occurred among fishes since these animals have occupied a place on the earth. Scientific efforts to understand the causes of disease in fishes, and to attempt to control them however, have only been made during the last sixty years.

Fishes, crustaceans and molluscs, as with other animals are subject to a wide spectrum of diseases, that can be classified as infectious or non-infectious. The vast majority of disease problems in the intensive farming of aquatic animals can be traced …


Bulletin 4307 - Grass Control In Pastures Using Herbicides, Alexandra Wallace Oct 1995

Bulletin 4307 - Grass Control In Pastures Using Herbicides, Alexandra Wallace

Bulletins 4000 -

This Bulletin discusses three methods for herbicide control of grasses in pastures:

  • pasture manipulation, in the early stages of pasture growth;
  • spray-topping late in the growing season; and
  • hay freezing, late in the growing season.


Pearl Farming In The Tuamotus: Atoll Development And Its Consequences, Moshe Rapaport Sep 1995

Pearl Farming In The Tuamotus: Atoll Development And Its Consequences, Moshe Rapaport

Pacific Studies

No abstract provided.


Ultrastructural Immunolocalization Of Histones (H2b, H3, H4), Transition Protein (Tp1) And Protamine In Rabbit Spermatids And Spermatozoa Nuclei. Relation To Condensation Of The Chromatin, J L. Courtens, Wilson Stephen Kistler, L Plöen Aug 1995

Ultrastructural Immunolocalization Of Histones (H2b, H3, H4), Transition Protein (Tp1) And Protamine In Rabbit Spermatids And Spermatozoa Nuclei. Relation To Condensation Of The Chromatin, J L. Courtens, Wilson Stephen Kistler, L Plöen

Faculty Publications

The histones H2B, H3 and H4, the transition protein TP1 and protamine were localised using ultrastructural immunocytochemistry in nuclei of rabbit spermatids and spermatozoa. Histones are present in round spermatid nuclei and are lost during the elongation of nuclei. TP1 and protamine appear simultaneously in all nuclei during this period. TP1 is located at the periphery of chromatin cords, while protamine seems to be located at random in the same cords. TP1 is lost in most elongated sprematids during step 13 of spermiogenesis, and the protamine stays in all sperm nuclei. TP1 remains persent in some old spermatids and ejaculated …


Author Index Aug 1995

Author Index

National Wildlife Research Center Repellents Conference 1995

Author Index


Chemical Signals And Repellency: Problems And Prognosis, Gary K. Beauchamp Aug 1995

Chemical Signals And Repellency: Problems And Prognosis, Gary K. Beauchamp

National Wildlife Research Center Repellents Conference 1995

The chemical senses (olfaction, gustation, and chemical irritation or pain) were likely the first to evolve. Their functions are among the most basic-to attract and to repel. Attracting compounds often signal food or sex; repelling compounds presumably signal danger. Among the chemical senses, only olfaction appears to have several functional roles, two of which are modulation of social behaviors and identification of food. Whether an odor attracts or repels often depends to a large degree on learning. Consequently, dissociated olfactory stimuli may be relatively poor candidates for repellents since, after repeated exposure, pest animals are likely to ignore them. Taste, …


Behavioral Principles Governing Conditioned Food Aversions Based On Deception, Michael R. Conover Aug 1995

Behavioral Principles Governing Conditioned Food Aversions Based On Deception, Michael R. Conover

National Wildlife Research Center Repellents Conference 1995

We often are unable to reduce wildlife damage because of our inability to apply a repellent directly to the plant, animal, or item that needs protection. Conditioned food aversions based on deception (CFABD) is one method that can be used to extend protection to these items (hereafter called models). In CFABD, the model is not treated; instead mimics of the model are created and then treated with a chemical that will sicken, but not kill, the animal consuming them. This approach is a reverse form of Batesian mimicry; normally the models are poisonous and the mimics are innocuous. Yet, the …


Effectiveness Of Capsaicin As A Repellent To Birdseed Consumption By Gray Squirrels, Christopher S. Fitzgerald, Paul D. Curtis, Milo E. Richmond, Joseph A. Dunn Aug 1995

Effectiveness Of Capsaicin As A Repellent To Birdseed Consumption By Gray Squirrels, Christopher S. Fitzgerald, Paul D. Curtis, Milo E. Richmond, Joseph A. Dunn

National Wildlife Research Center Repellents Conference 1995

We evaluated the efficacy of capsaicin as an aversive agent to captive and free-ranging gray squirrels (Sciurus carolinenssi). Capsaicin appeared more aversive in lipid-based formulations. Sunflower hearts treated with capsaicin oleoresins at 100,000 Scoville Heat Units (SHU's) demonstrated near-complete aversiveness to captive squirrels. These treatments were sampled by food-deprived captive squirrels, but were not consumed due to their extreme pungency. Additionally, capsaicin-treated suet was very effective at lower concentrations than was observed with seeds (24,000 SHU-suet versus 100,000 SHU-seed). Three ground-pepper treatments (A = 8,250 SHU's, B = 27,500 SHU's, and C = 82,500 SHU's) offered simultaneously with …


Dilution And Detoxication Costs: Relevance To Avian Herbivore Food Selection, Walter J. Jakubas, Christopher G. Gulgielmo, William H. Karasov Aug 1995

Dilution And Detoxication Costs: Relevance To Avian Herbivore Food Selection, Walter J. Jakubas, Christopher G. Gulgielmo, William H. Karasov

National Wildlife Research Center Repellents Conference 1995

Toxicity and digestive inhibition are commonly thought of as the primary postingestive consequences by which plant secondary metabolites (PSM's) limit herbivore food selection. However, food selection may also be modified by nutritional costs imposed by detoxication processes and nutrient dilution. Few studies have determined the magnitude of these costs for vertebrate herbivores and their ecological significance. Research clarifying the mechanisms by which PSM's repel animals may give new insights into the development of repellents for nuisance wildlife and improve our ability to predict ecological interactions involving herbivores. Using captive ruffed grouse (Bonasa umbellus), we tested whether PSM ingestion …


The Role Of Analytical Chemistry In Repellent Research, Bruce A. Kimball, Dale L. Nolte, Kevin L. Kelly, John J. Johnston Aug 1995

The Role Of Analytical Chemistry In Repellent Research, Bruce A. Kimball, Dale L. Nolte, Kevin L. Kelly, John J. Johnston

National Wildlife Research Center Repellents Conference 1995

Development of effective repellents requires in depth investigation of the interaction of animals with their chemical environment. This multidisciplinary field, chemical ecology, has received much attention in the area of plant/invertebrate herbivore interactions. At the Denver Wildlife Research Center (DWRC), we have benefited by the close collaboration of chemists and biologists when studying the interactions of vertebrates with natural products. Typically, this combines chemical assays that provide information on the characteristics of chemical cues with bioassays that generate information on the mechanisms that drive animal behavior. The chemistry role in this research can be either supportive or interactive. Two recent …


Avian Repellents: Options, Modes Of Action, And Economic Considerations, J. Russell Mason, Larry Clark Aug 1995

Avian Repellents: Options, Modes Of Action, And Economic Considerations, J. Russell Mason, Larry Clark

National Wildlife Research Center Repellents Conference 1995

The present manuscript considers visual, auditory, tactile, chemosensory, and physiologic repellents currently available for use in the United States. Discussion of tactile, chemosensory, and physiologic repellents is emphasized for three reasons. First, these products are preferred by users. Second, application of these substances is regulated by state and federal agencies. Third, only four active ingredients are legally available at the present time. This lack reflects difficulties in obtaining regulatory approval and limited market size.


Origins Of Food Preference In Herbivores, Frederick D. Provenza Aug 1995

Origins Of Food Preference In Herbivores, Frederick D. Provenza

National Wildlife Research Center Repellents Conference 1995

Food preference is best understood as the interaction between taste and postingestive feedback, determined by an animal's physiological condition and to a food's chemical characteristics. Taste (as well as smell and sight) enables animals to discriminate among foods and provides hedonic sensations associated with eating. Postingestive feedback calibrates taste in accord with a food's homeostatic utility: preference increases when foods are adequate in nutrients; conversely, preference decreases when foods are deficient in nutrients, when they contain excesses of toxins, and when they are too high in rapidly digestible nutrients. Preference also decreases when familiar foods are eaten too frequently or …


The Chemistry Of Plant/Animal Interactions, Paul B. Reichardt Aug 1995

The Chemistry Of Plant/Animal Interactions, Paul B. Reichardt

National Wildlife Research Center Repellents Conference 1995

Chemical approaches to studying plant/animal interactions have led to an appreciation that plant chemistry strongly influences patterns of herbivory. Although this chemistry is often rather complex, two basic factors have emerged: plant chemistry influences herbivores in both positive and negative ways by determining dietary quality of plants and by providing feeding cues. Examination of the results from numerous studies addressing these issues has led to the development of three working hypotheses: (1) there is a molecular basis for chemical cues; (2) the molecular diversity of chemical signals implies specific mechanisms for plant-initiated attraction or repellence of herbivores; and (3) there …