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Population Dynamics Of Ludwigia Leptocarpa (Onagraceae) And Some Factors Affecting Size Hierarchies In A Natural Population, Rebecca W. Dolan, Rebecca R. Sharitz Jan 1984

Population Dynamics Of Ludwigia Leptocarpa (Onagraceae) And Some Factors Affecting Size Hierarchies In A Natural Population, Rebecca W. Dolan, Rebecca R. Sharitz

Scholarship and Professional Work - LAS

  1. Germination cohorts of Ludwigia leptocarpa, a semi-aquatic annual plant were marked in the field at time of establishment and followed through the 1981 and 1982 growing seasons at a site in southern South Carolina.

  2. Data from each cohort were pooled to determine demographic characteristics of the population as a whole, then analyzed separately to determine the effect of time on germination on survivorship, relative growth rate, and adult size.

  3. Changes in numbers of L. leptocarpa fit a Deevey Type II survivorship curve. This and other characteristics of the species classify it as ‘r-selected’. Aspects of the life history may reflect …


Limitations On Spatial Memory In Mice, Robert H.I. Dale, Martin Bedard Jan 1984

Limitations On Spatial Memory In Mice, Robert H.I. Dale, Martin Bedard

Scholarship and Professional Work - LAS

Rats have an impressive ability to remember locations they have visited. Two experiments used an eight-arm radial maze to determine whether mice showed two important characteristics of this spatial memory: its durability, and its dependence on stimuli outside the maze (extreme stimuli). In Experiment 1, food-deprived mice were allowed to eat from four of the eight arms of the maze then, after delays of 5 sec, 1 min, or 5 min, they were permitted to choose the remaining arms. Choice accuracy declined significantly with the longer delays, but always remained above chance. In Experiment 2, the maze was rotated 180° …


Social Transmission Of Behavioural Traditions In A Coral Reef Fish, Gene Helfman, Eric T. Schultz Jan 1984

Social Transmission Of Behavioural Traditions In A Coral Reef Fish, Gene Helfman, Eric T. Schultz

EEB Articles

Traditional behaviours involve the non-genetic transmission of social information across age classes or generations. French grunts (Haemulon flavolineatum) exhibit social traditions of daytime schooling sites and twilight migration routes. Individuals transplanted to new schooling sites and allowed to follow residents at the new sites used the new migration routes and returned to the new sites in the absence of resident fish. Control fish with no opportunity to learn showed no such directionality or return. This is the first demonstration of apparent pre-cultural behaviour in free-living fish. Our observations suggest additional classes of behaviour and taxonomic groups in which …


Acanthohaustorius Pansus, A New Species Of Sand-Burrowing Amphipod From Looe Key Reef, Florida Keys, With Redescription And Distribution Data Of Acanthohaustorius Bousfieldi Frame, 1980 (Amphipoda: Haustoriidae), James Darwin Thomas, J. L. Barnard Jan 1984

Acanthohaustorius Pansus, A New Species Of Sand-Burrowing Amphipod From Looe Key Reef, Florida Keys, With Redescription And Distribution Data Of Acanthohaustorius Bousfieldi Frame, 1980 (Amphipoda: Haustoriidae), James Darwin Thomas, J. L. Barnard

Marine & Environmental Sciences Faculty Articles

A new species of sand-burrowing amphipod, Acanthohaustorius pansus, is described from carbonate sands of the Florida Keys Reef Tract. This is the first time the predominantly cold-water genus Acanthohaustorius has been reported south of Virginia coastal waters. Acanthohaustorius bousfieldi Frame, 1980, originally described from Long Island Sound, is refigured and reported from shell-hash sediments off the central Atlantic coast of Florida. A revised key to the species of Acanthohaustorius is presented.


Effect Of Membrane Filtration Of Antimalarial Drug Solutions On In Vitro Activity Against Plasmodium Falciparum, J. Kevin Baird, C. Lambros Jan 1984

Effect Of Membrane Filtration Of Antimalarial Drug Solutions On In Vitro Activity Against Plasmodium Falciparum, J. Kevin Baird, C. Lambros

United States Public Health Resources

Antimalarial activities ofchloroquine, mefloquine, amodiaquine, and quinine in vitro against Plasmodium falciparum were diminished as a consequence ofmembranefiltration. Filtered drug solutions gave ID50 values up to 25-fold greater than those of non-filtered (ethanol-sterilized) drug solutions. Loss ofactivity byfiltration was overcome by increasing the drug concentration prior to filtration. Water solutions filtered through Millex-GSfilter units consistently showed an absorbance maximum at 277 nm, accompanied by a lesser peak at 225 nm. Water filtrates from Nucleopore and Millex-G Vfilters showed no absorbance at 277 nm and only slight absorbance was evidentfor the Gelmanfilter unit. Activity losses were attributed to extractable contaminating …


Distinct Examples Of Immunologic Analysis In Molecular And Cellular Biology: Small Nuclear Ribonucleoproteins And The T Cell Receptor, David E. Fisher Jan 1984

Distinct Examples Of Immunologic Analysis In Molecular And Cellular Biology: Small Nuclear Ribonucleoproteins And The T Cell Receptor, David E. Fisher

Student Theses and Dissertations

Since the discovery (Tan and Kunkel, 1966; Mattioli and Peichlin, 1971; Sharp, et al., 1972) of human SLE autoantibodies directed against RNA-protein complexes in eucaryotic nuclei, a great deal of interest has been generated regarding both the relationships of antibody specificities to disease and the biological roles of the recognized antigens. These antibodies are some of the many autoantibody species which have been described in systemic lupus erythematosus (SLE) as well as other rheimatic disease conditions. A common feature of many of these reactivities is the apparent nuclear localization of antigen. Study of the antibodies as well as these antigens …


The Nonenzymatic Modification Of Proteins By Steroids And Dna By Reducing Sugars; In Vitro And In Vivo Studies, Richard J. Bucala Jan 1984

The Nonenzymatic Modification Of Proteins By Steroids And Dna By Reducing Sugars; In Vitro And In Vivo Studies, Richard J. Bucala

Student Theses and Dissertations

A number of studies have demonstrated that small metabolites can react nonenzymatically with proteins to form covalent, addition products. An example of this type of reaction is the modification of hemoglobin A by glucose to form the minor species hemoglobin A1c. In this case, glucose reacts by forming a reversible Schiff base adduct with the N-terminal valine of the β-chain of hemoglobin. The Schiff base intermediate then slowly undergoes an Amadori rearrangement to produce a stable ketoamine addition product. The following studies investigate two novel aspects of nonenzymatic addition reactions. The first is the demonstration that ketolic steroids, …


Research Objectives In Vertebrate Pest Control, A J. Oliver Jan 1984

Research Objectives In Vertebrate Pest Control, A J. Oliver

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

The European rabbit, introduced into Australia in 856 by an early settler for hunting, caused massive losses to agricultural production in Western Australia in 1940s and 1950s.

In those years most of the country's recources and efforts allocated to vertebrate pest problems were aimed at controlling this animal.

Research and control measures by Commonwealth and State agencies, including the introduction of myxomatosis, were largely responsible for reducing the rabbit problem to the comparatively minor one it is now.

Today, the Agricultural Protection Board is involved in the control of a much wider range of mammals and birds which cause losses …


The Bush Tick, R B. Besier Jan 1984

The Bush Tick, R B. Besier

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

A newly discovered livestock parasite has focused attention on farms in the Walpole district in the south-west of Western Australia. Ticks submitted to the Department of Agriculture in December 983 were identified as the bush tick, Haemaphysalis longicornis. An intensive campaign to locate areas of infestation and to limit spread was started in January 1984.

The bush tick is a pest of livestock in some areas of New South Wales and Queensland. It is important in a narrow coastal strip from Sydney to Brisbane where total summer rainfall can exceed 1000 mm. In this area heavy tick infestation causes …


Rabbit Kitten Survival In The South-West, D R. King Jan 1984

Rabbit Kitten Survival In The South-West, D R. King

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

In the South-West of Western Australis reliable winter rains allow the rabbit breeding season to extend through winter and spring, and thus a large number of kittens are produced each year.

Studies on the biology of rabbits at Cape Naturaliste (270 kilometres south-west of Perth) and Chidlow (40 kilometres east of Perth in the Datling Range) have shown that at these sites each doe produces about 30 and 27 kittens respectively a year. If all these youg rabbits survived, there would be a 15-fold increase in numbers. Within a short time the State would be covered "wall to wall" by …


Rabbits North Of Carnarvon, D R. King Jan 1984

Rabbits North Of Carnarvon, D R. King

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

In Westeern Australia rabbits are mainly a pest along the south-western coastal parts of the State, but there are populations north of the Tropic of Capricorn. Rabbits after crossing the Nullarbour plain from South Australia and colonising the South-West of the State, were reported to have reached the west coast near Geraldton by 1912 and then spread northwards.

There is little information on the biologhy of rabbits in the northan parts of their range, but pastoralists in some areas are concerned about erosion and damage to vegetation on their stations when rabbits reach high numbers.

The Agricultural Protection Board undertook …


The Secretive Silvereyes, I J. Rooke Jan 1984

The Secretive Silvereyes, I J. Rooke

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

Durinf the past five years the agricultural Protection Board, in co-operation with scientists from CSIRO's Division of Wildlife Research and the University of Western Australia, had studied the biology and control of the silvereye in the South-West of Western Asustralia. The project was partially funded by a voluntary levy on vignerons in the Margaret River and Mt Barker areas.

The first part of the study investigated the bird's bioloogy - its food requirements, reproductive rate, how it interacted with other birds and its seasonal movements, It was hoped that this knowledge would help develop effective techniques for either controlling the …


Preventing Vineyard Damage By Silvereyes, I J. Rooke Jan 1984

Preventing Vineyard Damage By Silvereyes, I J. Rooke

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

In the previous article, Dr I Rooke outlined the studies which helped to devise practical ways of controlling attacks by silvereyes on vineyards in the South-West of Western Australia. The preventative methods vignerons can use are discussed here.


A Closer Look At Parrots As Pests, John L. Long Jan 1984

A Closer Look At Parrots As Pests, John L. Long

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

Small parrots have been attacking fruit and grain crops in the south of Western Australia at least since agriculture expanded into their native habitats in the early 1900s. The parrots are capable of quickly adapting to new situations so it is not surprising that they have eaten crops.

It is not known whether parrot numbers have increased since European settlement began, but this appears likely. The present landscape of islands of uncleared country interspersed with areas of agriculture appears to favour the survival of the red-capped parrot, western rosella and the Port Lincoln parrot. These species were investigated during a …


Keeping Starlings Out Of W.A, John L. Long Jan 1984

Keeping Starlings Out Of W.A, John L. Long

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

In Europe and North America huge flocks of starlings cause millions of dollars worth of damage to grain and fruit crops each year and large sums of money are spent trying to control them.

Starlings were introduced into australia in the late 1890s when more than 200 birds were released near Melbourne. They are now well established over much of eastern Australia, ranging from central Queensland, south to Tasmania and along the Great Australian Bight to the South Australian-Western Australian border, occasionally crossing it and sometimes moving as far west as the Esperance region on the south coast.

Some people …


Skeleton Weed : How Serious A Threat In Western Australia?, F D. Panetta, J. Dodd Jan 1984

Skeleton Weed : How Serious A Threat In Western Australia?, F D. Panetta, J. Dodd

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

Skeleton weed is probably the most serious weed ever to threaten the Australian wheat industry. It interferes with wheat cropping at two stages: through competition with the growing crop, particularly for nitrogen and water during the crop's development: and later through the production of a tall, wiry flowering stem which tangles in harvesting machinery and can make harvesting difficult, if not impossible.

The weed is a major problem in eastern Australia although a combination of cultural, chemical and biological control programmes is helping to reduce its impact.

In Western Australia, skeleton weed is being contained mainly by eradication efforts. Weed …


Algal Growth And The Phosphorus Cycle, Arthur J. Mccomb, K. S. Hamel, A. L. Huber, D. K. Kidby, R. J. Lukatelich Jan 1984

Algal Growth And The Phosphorus Cycle, Arthur J. Mccomb, K. S. Hamel, A. L. Huber, D. K. Kidby, R. J. Lukatelich

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

Larger algae and microscopic phytoplankton foul the waters of the Peel-Harvey estuarine system, upsetting the fishery and polluting the beaches.

These aquatic plants grow in response to phosphorus runoff from drainage, trapping phosphorus in the estuary and using it in their growth. When they die this phosphorus remains in the system to be recycled for further plant growth.

Algal pollution in the estuary can be lessened by reducing the amount of phosphorus entering the system, increasing phosphorus losses to the ocean, or in some way blocking the trapping and recycling processes.


Soil Acidity And Legume Nodulation, J G. Howieson, M. A. Ewing Jan 1984

Soil Acidity And Legume Nodulation, J G. Howieson, M. A. Ewing

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

Nitrogen is a basic constituent of protien and is essential to all forms of life. Many agricultural plants are legumes - a group of plants which, in co-operation with specialised soil bacteria, fix their own nitrogen from the air. When the legume dies, the organic matter breaks down anf the nitrogen becomes available to the following crops.

Soil acidity is a major factor limitimg the successful association between legumes and their beneficial soil bacteria in Western Australia.


Herbivory Effects On Thalassia Testudinum Leaf Growth And Nitrogen Content, J. C. Zieman, R. L. Iverson, John C. Ogden Jan 1984

Herbivory Effects On Thalassia Testudinum Leaf Growth And Nitrogen Content, J. C. Zieman, R. L. Iverson, John C. Ogden

Integrative Biology Faculty and Staff Publications

The pattern of turtle grazing on Thalassia testudinum in St. Croix seagrass beds begins with the establishment of a grazing plot by initial removal of leaf blades, followed by repeated grazing of several centimeter-long leaf blades within a maintained grazing area. Plants within the grazed area exhibit increased specific growth rate as a consequence of increased light flux to unepiphytized leaf bases. Leaf width is reduced in the grazed area as a consequence of grazing stress. The leaf bases contain a higher proportion of nitrogen and a lower lignin content than the leaf tips, in addition to lacking epiphytes. Our …


South Dakota Farm And Home Research, South Dakota State University Jan 1984

South Dakota Farm And Home Research, South Dakota State University

South Dakota Farm and Home Research: 1949 -1998

Director’s Comments [p] 2
Just another pretty face: don’t be taken in by her looks. There’s little connection between appearances and the ability to conceive early and easily [p] 3
Not big enough: Bigger is better in the case of alcohol fuels plants, but bigger may mean some public policy decisions. Do we make them? [p] 5
Keeping weevils down: they do their damage to heads but live most of their lives in the soil. Seems we should be able to keep them down there [p] 9
Energy vs. runoff: water lost can wipe out dollars saved with low-pressure sprinklers, …


Redescription And Distribution Of Muilla Coronata (Liliaceae), James R. Shevock Jan 1984

Redescription And Distribution Of Muilla Coronata (Liliaceae), James R. Shevock

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Die Mongoleisammlung Im Herbarium Der Martin-Luther-Universität Halle-Wittenberg, Werner Hilbig Jan 1984

Die Mongoleisammlung Im Herbarium Der Martin-Luther-Universität Halle-Wittenberg, Werner Hilbig

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Das Herbarium der Martin-Luther-Universität Halle-Wittenberg besitzt eine umfangreiche Sammlung von Pflanzen aus der Mongolei. Das im wesentlichen während gemeinsamer deutsch-mongolischer biologischer Expeditionen gesammelte Material liegt als selbständige Sammlung vor. Sie enthält ca. 8000 Bögen höherer Pflanzen und umfaßt ca. 1300 determinierte Arten. Ein bedeutender Teil wurde von Spezialisten bestimmt. Umfangreich sind auch die Aufsammlungen von Flechten und Moosen , geringer die von Pilzen. Es konnten hierbei wie bei den höheren Pflanzen zahlreiche Erstnachweise erbracht werden.

In der Hauptsammlung des Herbariums sind Herbarbelege v on Pflanzen des mongolischen und südsibirischen Raumes aus dem 19. Jahrhundert enthalten, z. T. von A . …


Zur Verbreitung Und Chemie Von Flechten Der Mongolischen Volksrepublik, Siegfried Huneck, Josef Poelt, Teuvo Ahti, Orvo Vitikainen, Ulzijn Cogt Jan 1984

Zur Verbreitung Und Chemie Von Flechten Der Mongolischen Volksrepublik, Siegfried Huneck, Josef Poelt, Teuvo Ahti, Orvo Vitikainen, Ulzijn Cogt

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Für das Gebiet der MVR werden Fundpunkte von 102 Flechtenart;en mitgeteilt. Davon sind 11 Arten neu für die MVR. 21 Arten wurden chemisch analysiert.

На территории МНР были собраны на разных местах 102 вида лижайников. Из них 11 вид является нозыми для МНР и для 21 вида проводился химический анализ.


Vergleichend Biologisch-Ökologische Untersuchungen In Hochgebirgen Der Nordwest- Und Südmongolei: Allgemeiner Bericht, Werner Hilbig, Michael Stubbe, N. Dawaa, Z. Schamsran, M. Dorn, K. Helmecke, D. Bumžaa, K. Ulykpan Jan 1984

Vergleichend Biologisch-Ökologische Untersuchungen In Hochgebirgen Der Nordwest- Und Südmongolei: Allgemeiner Bericht, Werner Hilbig, Michael Stubbe, N. Dawaa, Z. Schamsran, M. Dorn, K. Helmecke, D. Bumžaa, K. Ulykpan

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In den Jahren 1976 bis 1978 führten Biologen der Martin-Luther-Universität HalleWittenberg und der Staatlichen Mongolischen Universität Ulan-Bator Arbeiten zur Höhenstufenzonierung des Charchiraa-Gebirges in der Nordw estmongolei d urch. In der Steppen- (1340 m), Lärchenwald- (2150 m) und alpinen Zone (2375 m) wurden Meßstationen errichtet, in denen über mehrere Wochen der Monate Juni bis August gearbeitet wurde. Paralleluntersuchungen konnten im Juni/Juli 1979 in dem ariden Gebirgszug Ich-bogd im Gobi-Altai (Halbwüste 1300 m, Bergsteppe 2500 m, alpine Matte 2740 m) durchgeführt werden. Der allgemeine Bericht .informiert über Aufgabenstellung, Ablauf der Expeditionen, Untersuchungsmethoden, Lage, Geologie und Klima der Untersuchungsgebiete sowie über allgemeine Erkenntnisse …


A Biosystematic Study Of The Fern Genus Lygodium In Eastern North America, Violet M. Brown Jan 1984

A Biosystematic Study Of The Fern Genus Lygodium In Eastern North America, Violet M. Brown

Retrospective Theses and Dissertations

The mainly tropical genus Lygodium differs from other ferns in that the fronds are indeterminate and are vine-like. A single species, L. palmatum is native in temperate North America. The temperate Asian L. japonicum is naturalized throughout much of the southeastern United States. About twenty years ago, L. microphyllum was introduced into South Florida and is now naturalized in several counties. The present study documents differences among spores and their generation, development of sporophytes from the fertilized egg, and in flavonoid chemistry. Hybridization experiments showed a strong possibility for cross fertility between species. Experiments with prothallial development and differentiation revealed …


Effects Of Excess Arginine With And Without Supplemental Lysine On Performance, Plasma Amino Acid Concentrations And Nitrogen Balance Of Young Swine, L. C. Anderson, A. J. Lewis, E. R. Peo, Jr., J. D. Crenshaw, Win Butler Jan 1984

Effects Of Excess Arginine With And Without Supplemental Lysine On Performance, Plasma Amino Acid Concentrations And Nitrogen Balance Of Young Swine, L. C. Anderson, A. J. Lewis, E. R. Peo, Jr., J. D. Crenshaw, Win Butler

Department of Animal Science: Faculty Publications

Three experiments were conducted to determine the effects of excess arginine on performance, plasma amino acid levels and N balance of young pigs (initial weights 6.9, 7.0 and 10.3 kg, respectively). In a 28-d growth trial, various amounts of arginine (0 to 1.6%) were added to a conventional starter diet.


Dummy-Elicited Aggressive Behavior In The Polychromatic Midas Cichlid, George W. Barlow, William Rogers, Alan B. Bond Jan 1984

Dummy-Elicited Aggressive Behavior In The Polychromatic Midas Cichlid, George W. Barlow, William Rogers, Alan B. Bond

Alan Bond Publications

Aggressive responses of 12 individuals of the polychromatic Midas cichlid Cichlasoma citrinellum were tested with five different sizes of neutrally colored (spot pattern) life-like dummies. The dummies were presented daily over six days, for one minute apiece, in a balanced design. Color (gold or normal morph) and sex of the subjects were varied independently. The attacks and threats at the dummies were positively correlated in their occurrence so they were combined to yield an aggregate measure of aggression. Attacks on blinded juveniles, five minutes before and five minutes after viewing a dummy, were analyzed to test for the occurrence of …


G84-717 Fleas And Their Management (Revised January 1993), Shripat T. Kamble, David L. Keith Jan 1984

G84-717 Fleas And Their Management (Revised January 1993), Shripat T. Kamble, David L. Keith

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide provides information on flea biology and how to solve flea problems.

Fleas are among the most annoying pests known to humans. In ancient times, fleas were even indicted, found guilty and sentenced to condemnation. Today, the verdict remains the same.

In Nebraska, fleas are common household pests attacking dogs, cats and sometimes people. In addition to these, several other flea species occur in Nebraska, feeding principally on rodents and occasionally on poultry and livestock. The information provided in this publication will focus primarily on cat and dog fleas, as they are the most commonly encountered species.


Vessel Grouping In Dicotyledon Wood, Sherwin Carlquist Jan 1984

Vessel Grouping In Dicotyledon Wood, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

A hitherto unappreciated correlation exists between nature of vessel grouping and nature of imperforate tracheary elements in wood of dicotyledons at large: families and genera with true tracheids (large fully bordered pits common on both radial and tangential walls) have solitary vessels. Presence of true tracheids as a subsidiary conductive system is hypothesized to render vessel grouping a superfluous adaptation. Vessel grouping does occur to various degrees in taxa with fiber-tracheids or libriform fibers; the degree of grouping is related to likelihood or seriousness of vessel failure by air embolisms because of either drought or frost. Grouping of vessels is …


The Impact Of Nitrification On Soil Acidification And Cation Leaching In A Red Alder Ecosystem, H. Van Miegroet, D. W. Cole Jan 1984

The Impact Of Nitrification On Soil Acidification And Cation Leaching In A Red Alder Ecosystem, H. Van Miegroet, D. W. Cole

Watershed Sciences Faculty Publications

The objectives of this study were to investigate the impacts of internal nitrification on soil and soil solution acidity and on the rate of nutrient export through NO3– mediated leaching. This was achieved by comparing soil chemical properties and soil solution composition within a naturally N-rich red alder (Alnus rubra Bong.) ecosystem to those of an adjacent Douglas-fir [Pseudotsuga menziesil (Mirbel) Franco] forest where soil N levels were significantly lower and no measurable HNO3 production could be observed. In the red alder system, where > 100 kg ha–1 yr–1 of N were added through symbiotic N2 fixation, the net annual NO3– …