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A Revision Of The Genus Strategus (Coleoptera: Scarabaeidae), Brett C. Ratcliffe Jan 1976

A Revision Of The Genus Strategus (Coleoptera: Scarabaeidae), Brett C. Ratcliffe

Bulletin of the University of Nebraska State Museum (1924–2023)

The New World genus Strategus Kirby is here defined and revised for the first time. Eight species are described as new: S. atlanticus, S. caymani, S. craigi, S. hipposiderus, S. howdeni, S. longichomperus, S. symphenax, and S. tarquinius; 12 new junior synonyms are established (including the rejection of six previously valid species)'; one species is raised from synonymy; and two new replacement names are proposed. Strategus now contains one fossil species and 31 valid extant species. A key to the males and females of all the species is provided for the first …


Mif-Like Activity In Non-Stimulated And Virus-Infected Cell Cultures, Eve Welling Brown Jan 1976

Mif-Like Activity In Non-Stimulated And Virus-Infected Cell Cultures, Eve Welling Brown

MUSC Theses and Dissertations

Macrophage migration inhibition factor (MIF) is a lymphocyte-derived substance which plays an important role in cell mediated immunity. Soluble factors containing MIF-like activity and produced by non-stimulated and virus-infected non-lymphoid cells have also been reported. In the present study, a MIF-like factor was repeatedly detected in Buffalo green monkey kidney cells infected with mumps or herpes simplex virus (HSV) indicating that this substance is reproducible and can be stimulated by a RNA and a DNA virus. Wistar-38 (WI-38) cell cultures also increased production of this substance in response to mumps but not HSV infection, indicating that the production of this …


Studies Of Plant Viroid Rna And Other Rna Species Of Unusual Function, Elizabeth Dickson Jan 1976

Studies Of Plant Viroid Rna And Other Rna Species Of Unusual Function, Elizabeth Dickson

Student Theses and Dissertations

This dissertation concerns studies of plant viroid RNA and other RNA species of unusual function. By "RNA species of unusual function" we mean RNA species which do not function as transfer, ribosomal or messenger RNA. In the studies to be reported here we have laid the experimental and theoretical foundation for investigating the role of RNA in the control of gene expression. In Chapter I the various standard techniques of RNA fingerprinting and sequencing have been applied to RNA molecules labeled in vitro with 125I. Fingerprints of human 5S RNA and bacteriophage f2 RNA resemble those of their noniodinated …


Non-Histone Nuclear Proteins : Patterns Of Synthesis And Phosphorylation During The Cell Cycle, Redistribution At Times Of Gene Activation And Properties Of Subsets Interacting With Hnrna, Jonathan Karn Jan 1976

Non-Histone Nuclear Proteins : Patterns Of Synthesis And Phosphorylation During The Cell Cycle, Redistribution At Times Of Gene Activation And Properties Of Subsets Interacting With Hnrna, Jonathan Karn

Student Theses and Dissertations

The interphase nucleus contains large numbers of nonhistone proteins, the majority of which are associated with chromatin. The amount and number of these proteins varies according to cell type. Actively proliferating cells with high transcriptional activity contain considerably more nonhistone nuclear proteins than do quiescent cells. In every cell type, the nuclear proteins are heterogeneous ; recent estimates based on two-dimensional gel electrophoresis place the total number of different HeLa cell chromosomal proteins at over 470 (Peterson and McConkey, 1976). Many of these proteins exhibit enzymatic activities associated with nuclear functions (such as DNA synthesis and repair, RNA synthesis, post-synthetic …


Armyworm Control In Coarse Grain Crops, G D. Rimes Jan 1976

Armyworm Control In Coarse Grain Crops, G D. Rimes

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

Investigations of armyworm infestations carried out in Western Australia during 976 have shown that a complex of three species is involved in the spasmodic outbreaks that may cause damage to course grain crops.

This article looks at the economics of control methods.


New Control For Esperance Armyworms, G R. Strickland, G. D. Rimes Jan 1976

New Control For Esperance Armyworms, G R. Strickland, G. D. Rimes

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

Armyworms are periodically responsible for serious cereal crop damage in Australia, often causing up to 80 per cent crop loss.

Amajor outbreak at Esperance in 1975 resulted in some 14,200 ha requiring treatment.

This was the first serious outbreak of armyworm for nine years in Western Australia.

A major new problem in the control of armyworm outbreaks is that use of DDT has been restricted by residue and withholding period problems, especially with a crop such as barley in which the grain is unprotected by glumes.

The trial results suggest that trichlorfon is a suitable material to eradicate armyworms and …


Root Rot Of Subterranean Clover In W.A, G C. Macnish, M. J. Barbetti, D. Gillespie, K. Hawley Jan 1976

Root Rot Of Subterranean Clover In W.A, G C. Macnish, M. J. Barbetti, D. Gillespie, K. Hawley

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

Root rot of subterranean clover has occurred sporadically in the south west of Western Australia for a number of years.

In most seasons the disease has affected the clover paddocks of only a few farms, but in 1973 there was widespread pasture decline due to root rot in the South-West and south coastal districts.

At present the most promising approaches for minimising the effect of root rot appear to be the use of cultivation techniques and eventually the use of resistant varieties, or other pasture species.


Lupin Split Seed : A Disorder Of Seed Production In Sweet, Narrow-Leafed Lupins, M W. Perry, J. W. Gartrell Jan 1976

Lupin Split Seed : A Disorder Of Seed Production In Sweet, Narrow-Leafed Lupins, M W. Perry, J. W. Gartrell

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

Commercial seed production from narrow-leafed lupins (Lupinus angustifolius L.) began in Western Australia in 1967, based on the newly-bred low alkaloid cultivar Uniwhite. The release of improved cultivars has led to the crop's wide acceptance and more than 100 000 ha were sown to sweet lupins in 1975.

With the greater area and wider range of soil types devoted to lupins, a developmental abnormality of the seeds, which became known as "split seed", was observed in some situations.


Green Lemons Safe From Fruit Fly, A N. Sproul Jan 1976

Green Lemons Safe From Fruit Fly, A N. Sproul

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

Importers' demands for fruit imports to be free of local pests places great restrictions on the movement of fruit between States, between countries, and sometimes within a State.

In Western Australia a Fresh Fruit Disinfestation Committee was formed in 1969 to direct State research aimed at developing techniques for post-harvest fruit sterilsation Programmes are supported by State and Federal funds and, in W.A., have provided staff and facilities to work on Mediterranean fruit fly. Parallel work with Queensland fruit fly and codlin moth is being done in New South Wales and Victoria.


Wild Oats In W.A, J G. Paterson Jan 1976

Wild Oats In W.A, J G. Paterson

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

A summary of background information, recent research findings and current recommendations for the control of wild oats in Western Australia.


The Interaction Of Phenanthridinium Derivatives With Nucleic Acids, Antonis Kindelis Jan 1976

The Interaction Of Phenanthridinium Derivatives With Nucleic Acids, Antonis Kindelis

Dissertations

No abstract provided.


The Role Of Methionine-192 In The Activation And Catalytic Mechanism Of Chymotrypsin, William J. Treadway Jan 1976

The Role Of Methionine-192 In The Activation And Catalytic Mechanism Of Chymotrypsin, William J. Treadway

Dissertations

No abstract provided.


Reproductive Parameters For Nine Avian Species At Moore Creek, Merritt Island National Wildlife Refuge, G. Tanner Girard Jan 1976

Reproductive Parameters For Nine Avian Species At Moore Creek, Merritt Island National Wildlife Refuge, G. Tanner Girard

Retrospective Theses and Dissertations

No abstract provided.


Availability Of Trypotophan In Some Feedstuffs For Swine, Pedro H. Rivera L., E. R. Peo, Jr., T. Stahly, B. D. Moser, P. J. Cunningham Jan 1976

Availability Of Trypotophan In Some Feedstuffs For Swine, Pedro H. Rivera L., E. R. Peo, Jr., T. Stahly, B. D. Moser, P. J. Cunningham

Department of Animal Science: Faculty Publications

Two experiments were conducted to determine the availability of tryptophan (Try) from corn (NC), opaque-2 corn (OC), milo (M) and freeze dried alfalfa (FDA) when fed to swine. The first experiment consisted of a growth trial involving 96 baby pigs and eight treatments. The basal diet containing .06% Try and 24.5% protein was supplemented with .015%, .030% and .045% L-Try. These four diets were used to establish a standard curve for growth. The other treatments were formed by adding the feedstuffs as the source of Try to the basal diet. Availabilities were determined by comparing growth responses. Try availabilities from …


Some Remarks On The Fecundity Of Tilapia (T. Mossambica Peters) And Its Introduction Into Middle Central America (Nicaragua) Together With A First Contribution Towards The Limnology Of Nicaragua, Dietmar Riedel Jan 1976

Some Remarks On The Fecundity Of Tilapia (T. Mossambica Peters) And Its Introduction Into Middle Central America (Nicaragua) Together With A First Contribution Towards The Limnology Of Nicaragua, Dietmar Riedel

Investigations of the Ichthyofauna of Nicaraguan Lakes

a. This paper presents an account of fecundity studies into T. mossambica under Middle Central American conditions and limnological investigations into Lake Moyua/Nicaragua which have been performed during 1961/62.

b. Data obtained as to fecundity of T. mossambica are discussed in the light of the term prolificy and with regard to ecological and biological characteristics of Nicaraguan waters and native fish fauna.

c. A more detailed contemplation about the possible effects of a spread out or transplantation of T. mossambica into other Nicaraguan waters concludes the paper.


Derivation Of The Freshwater Fish Fauna Of Central America, George S. Myers Jan 1976

Derivation Of The Freshwater Fish Fauna Of Central America, George S. Myers

Investigations of the Ichthyofauna of Nicaraguan Lakes

The nature, composition, and evolution of Centra) American freshwater fish groups are discussed in relation to the history and derivation of the faunal elements. It is concluded that the entire area between the Isthmus of Tehuantepec and eastern Panama was and always had been devoid of primary (obligatory) freshwater fishes prior to the very late Tertiary. Instead, secondary freshwater fishes evolved in this area during the Neogene and perhaps for a longer period, the Poeciliidae having probably had a longer history within the area than the Cichlidae. In the late Tertiary a very few North American immigrants entered the area …


Geographic Distribution Of The San Juan Ichthyofauna Of Central America With Remarks On Its Origin And Ecology, William A. Bussing Jan 1976

Geographic Distribution Of The San Juan Ichthyofauna Of Central America With Remarks On Its Origin And Ecology, William A. Bussing

Investigations of the Ichthyofauna of Nicaraguan Lakes

The scientific study of fishes of the Great Lakes of Nicaragua began in 1864 with the description by Gunther of Heros labiatus (=Cichlasoma labiatum) from Lake Managua. Subsequently, Gunther reported on several other species collected in the Great Lakes by Captain J. M. Dow. Astorqui (1967) reviewed the sparse ichthyological literature dealing with Nicaraguan fishes and pointed out the paucity of recent studies. Since then Villa (1971) has produced a provisional list of the freshwater and brackish water fishes of Nicaragua and Astorqui (1972) has analyzed the ichthyofauna of the Great Lakes Basin. Riedel (1972) discussed the geological …


Some Speculations About "The Great Nicaraguan Lake", Jaime Villa Jan 1976

Some Speculations About "The Great Nicaraguan Lake", Jaime Villa

Investigations of the Ichthyofauna of Nicaraguan Lakes

The available evidence indicates that Lakes Managua and Nicaragua were broadly connected in the past, when most of the fish species invaded the "Great Nicaraguan Lake". Due to the lowering of the water level (caused perhaps by tectonic movements and/or erosion produced by the Rio San Juan), Lake Managua became separated from Lake Nicaragua in the Tipitapa area. Water movement from Lake Managua is achieved mostly by seepage through a porous dropoff which prevents the exchange of fishes between the lakes. At about the same time, if not earler, Lake Xilml also became separated. After the more or less permanent …


Lake Nicaragua Fishery Resources, William D. Davies Jan 1976

Lake Nicaragua Fishery Resources, William D. Davies

Investigations of the Ichthyofauna of Nicaraguan Lakes

Data collected during this survey indicated that the number of full-time fishermen has not increased appreciably over the past several years. However, it is likely that, if the demand for fish were to increase, a number of the present part-time fishermen would increase their effort to full-time. Indications are strong that the fish catch from this lake could at least be doubled by the existing population of fishermen, using the same gear, if market conditions were such as to encourage greater fishing effort.
The lake's overall fisheries resources are far from being exploited to their maximum, with the possible exception …


Ontogeny Of Parent-Contacting In Young Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes, George W. Barlow Jan 1976

Ontogeny Of Parent-Contacting In Young Cichlasoma Citrinellum (Pisces, Cichlidae), David L. G. Noakes, George W. Barlow

Investigations of the Ichthyofauna of Nicaraguan Lakes

There is an extensive literature on cichlid fish behavior, but most of this treats the behavior of adults (see BREDER & ROSEN, I966, for example). Much of this is based on laboratory observations with little corroborative information from field studies. Recently there has been an increasing trend to study the development of behavior, in cichlids as in other animals. In part this results from the 'nature-nurture' controversy regarding factors control~ ling behavior (e.g. KRUIJT, I964). However, there is also interest in the study of young animals for their own sake (e.g. WARD & BARLOW, I967).
The present study was undertaken …


Competition Between Color Morphs Of The Midas Cichlid, Cichlasoma Citrinellum, In Lake Jiloá, Nicaragua, Kenneth R. Mckaye, George W. Barlow Jan 1976

Competition Between Color Morphs Of The Midas Cichlid, Cichlasoma Citrinellum, In Lake Jiloá, Nicaragua, Kenneth R. Mckaye, George W. Barlow

Investigations of the Ichthyofauna of Nicaraguan Lakes

Color polymorphism, or polychromatism, is a recurring phenomenon throughout the animal kingdom. In fishes one form, the goldfish, is particularly notable because of its conspicuousness and its occurrence in nature in such a large number of widely unrelated species; yet it is seldom common in anyone species (Webber et al., 1973). The Midas cichlid, Cichlasoma citrinellum, is unusual in this respect because in many of the lakes where it occurs in Nicaragua brilliantly colored morphs are relatively common. These morphs lack the species-typical dark markings, and individuals vary smoothly from white through yellow, orange, red, and mixtures of …


The Status Of The Freshwater Shark Of Lake Nicaragua, Thomas B. Thorson, Donald E. Watson, C. Michael Cowan Jan 1976

The Status Of The Freshwater Shark Of Lake Nicaragua, Thomas B. Thorson, Donald E. Watson, C. Michael Cowan

Investigations of the Ichthyofauna of Nicaraguan Lakes

Nineteen sharks collected from freshwater at several points on Lake Nicaragua and the Rio San Juan were all of the same species and indistinguishable from marine Carcharhinus leucas of the Atlantic. Minor differences previously thought to separate C. leucas from the lake shark proved to be invalid. Females had slightly longer gill slits, somewhat greater breadth of pelvic fin, and a longer abdominal region than males. Clasper length indicated that the onset of sexual maturity in males occurs when they are between 1,600 and 1,700 mm in total length.
The classical theory or origin of the sharks from Pacific ancestry …


Comparison Of Some Parameters Of Serum And Uterine Fluid Of Pregnant, Viviparous Sharks (Carcharhinus Leucas) And Serum Of Their Near-Term Young, Thomas B. Thorson, Jeffrey W. Gerst Jan 1976

Comparison Of Some Parameters Of Serum And Uterine Fluid Of Pregnant, Viviparous Sharks (Carcharhinus Leucas) And Serum Of Their Near-Term Young, Thomas B. Thorson, Jeffrey W. Gerst

Investigations of the Ichthyofauna of Nicaraguan Lakes

I. In eight females, serum urea concentrations of 134-336 mM/l. were interpreted as indications of previous environmental salinities.
2. Fetal serum solute concentrations usually resembled those of the mother, but in two cases where fetal urea was higher, it was interpreted as a lag in urea reduction following movement from salt to fresh water.
3. Uterine fluid was similar to maternal serum in all parameters except for its very low protein content.
4. No flushing of the uteri with environmental water occurs.
5. Independent osmoregulation apparently does not occur before birth, although required mechanisms may be present.
6. The full …


The Rectal Gland In Relation To The Osmoregulatory Mechanisms Of Marine And Freshwater Elasmobranchs, Giuseppe Gerzeli, Gian Franco De Stefano, Lorenzo Bolognani, Kurt W. Koenig, Maria Victoria Gervaso, Maria Fausta Omodeo-Salé Jan 1976

The Rectal Gland In Relation To The Osmoregulatory Mechanisms Of Marine And Freshwater Elasmobranchs, Giuseppe Gerzeli, Gian Franco De Stefano, Lorenzo Bolognani, Kurt W. Koenig, Maria Victoria Gervaso, Maria Fausta Omodeo-Salé

Investigations of the Ichthyofauna of Nicaraguan Lakes

The rectal gland of elasmobranchs secretes large quantities of electrolytes and is of primary importance in the osmoregulatory mechanisms of these animals (Burger and Hess, 1960; Burger, 1962). Analogously, various organs of other vertebrates are also known to be involved in salt secretion (Schmidt-Nielsen, 1965; Bonting, 1970; Bentley, 1971). In general, active ion transport is the basis of this phenomenon; in any case, it requires the presence of structural devices, morphologically and chemically well defined, and of metabolic capabilities which, taken singly, are not specific, but collectively are consistent with active ion transport and salt secretion.


G76-312 What Are Good Labor Relations?, Robert E. Perry Jan 1976

G76-312 What Are Good Labor Relations?, Robert E. Perry

University of Nebraska-Lincoln Extension: Historical Materials

Good labor relations is the factor most often identified as necessary for successful employment by farm employees. Farmers who employ hired labor also rate "good labor relations" as an important factor, though many rate good wages as more important

What are "good labor relations"? From answers received from employees, they appear to involve a mixture of human characteristics and open communications that build mutual respect and loyalty.


Summary Of 1976 Field Trials, D J. Gilbey Jan 1976

Summary Of 1976 Field Trials, D J. Gilbey

Experimental Summaries - Plant Research

Doublegee seed longevity. Doublegee control. Crop yield loss - doublegee. Creeping knotweed. Guildford grass. Time of spraying 2, 4-D. Longevity of doublegee seed under continuous pasture. Locality: Avondale, Wongan Hills and Chapman Research Stations. Effect of double cropping, shallow dry cultivation and spraying pasture on viable doublegee seed - 74A4. Locality: Avondale Research Station. Effect of doublegee cropping, shallow dry cultivation and spraying pasture on viable doublegee seed - 74WH4. Locality: Wongan Hills Research Station. Doublegee seed longevity x cultivation - 75WH65. Locality: Wongan Hills Research Station. Doublegee seed longevity x cultivation - 74C7. Locality: Chapman Research Station. Doublegee seed …


The Mediterranean White Lupin, John Sylvester Gladstones Jan 1976

The Mediterranean White Lupin, John Sylvester Gladstones

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

"If you want to bring in a good lupin harvest, thrash your wife soundly before you go out sowing in the field". Old Syrian Proverb.

Lupin breeder Dr. John Gladstones does not beat his wife as recommended in the Syrian proverb above. Nor is he known to use ground up lupin seeds for the diverse cosmetic and medicinal purposes recommended in ancient Roman and other texts on lupins.

But his modern work on lupin breeding and development has undoubtedly been influenced by his detailed study of such writings.

In this article he discusses the history of the Mediterranean white lupin …


The Control Of Annual Ryegrass, Geoffrey A. Pearce, J. E. Holmes Jan 1976

The Control Of Annual Ryegrass, Geoffrey A. Pearce, J. E. Holmes

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

A valuable pasture plant - one of the worst weeds if cereal crops - host to a potent animal disease toxin.....annual ryegrass is the subject of intensive studies by the Department of Agriculture.

This article reviews current research into the control of annual ryegrass in crops.


Description Of Aspen Communities And Related Wildlife Populations In The Phosphate Strip Mining Area Of Southeastern, Idaho, David S. Winn Jan 1976

Description Of Aspen Communities And Related Wildlife Populations In The Phosphate Strip Mining Area Of Southeastern, Idaho, David S. Winn

Aspen Bibliography

No abstract provided.


Aspen Forest After Harvest, Norbert V. Debyle Jan 1976

Aspen Forest After Harvest, Norbert V. Debyle

Aspen Bibliography

Aspen is a unique forest tree with respect to regeneration. It produces abundant root suckers, up to 40,000 per acre are common, after clearcutting or fire removes the parent stand. The rapidly growing sucker stand competes well with other vegetation, but is susceptible to destruction by excessive ungulate browsing. Clearcut areas produce more streamflow and more growth on shrubs and herbaceous vegetation than does the uncut forest. The patchwork of age classes that results from even-age management optimizes wildlife habitat requirements for several desired species.