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Gene Activation In Early Amphibian Development, Rosemary Faulkner Bachvarova Jan 1966

Gene Activation In Early Amphibian Development, Rosemary Faulkner Bachvarova

Student Theses and Dissertations

The amphibian embryo has been a fascinating object for study for a century or more. It is large in size, widely available, and easy to observe throughout embryogenesis. The control of early development and the role of the genes have also been investigated for a long time. The combination of older morphological and more recent biochemical descriptions of development under normal and experimental conditions are bringing us closer to an understanding of the mechanism of early differentiation. In the General Introduction to this thesis the role of the nucleus and cytoplasm in amphibian development are discussed. Other types of embryos …


Studies On Selection In Natural And Experimental Populations Of Drosophila Pseudoobscura, Wyatt W. Anderson Jan 1966

Studies On Selection In Natural And Experimental Populations Of Drosophila Pseudoobscura, Wyatt W. Anderson

Student Theses and Dissertations

Two genetic characters in Drosophila pseudoobscura were utilized in an investigation of some of the genetic mechanisms in evolution. The characters are (1) body size, which is a continuously-varying, polygenic trait, and (2) the arrangement of genes along the third chromosome, which is a Mendelizing, discrete trait. Collections of Drosophila pseudoobscura were taken in many localities in the American West. The two characters vary regularly with the physiographic division of the West. This variation is evidence that the frequencies of the genes controlling each character are strongly regulated by selection; such variation is the first stage in the genetic divergence …


Stocking Rates On Cyprus Barrel Medic In The Northern Wheatbelt, R J. Parkin Jan 1966

Stocking Rates On Cyprus Barrel Medic In The Northern Wheatbelt, R J. Parkin

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

IN May 1963, some three weeks after germination, a 4th year stand of Cyprus barrel medic was stocked with Merino wethers.

These same sheep are still grazing the area after three years.


Poison Plants In The Garden, T E H Aplin Jan 1966

Poison Plants In The Garden, T E H Aplin

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

SOME 18 commonly grown garden plants are known to be toxic and many local home gardens have five or six of them.

Several other species can cause skin ailments.


The Recent Story Of Skeleton Weed : A Menace To Our Wheat Industry, G R W Meadly Jan 1966

The Recent Story Of Skeleton Weed : A Menace To Our Wheat Industry, G R W Meadly

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

SKELETON WEED was first found in Western Australia at Ballidu in 1963.

No further recording was made until December of last year when a small area was located near Esperance, but, within a brief period, plants were reported from Geraldton and Kwinana.


Trees Of Western Australia, Charles Austin Gardner Jan 1966

Trees Of Western Australia, Charles Austin Gardner

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

It is not desirable to give locality names to plants unless their range is fully underwood.

Such names can be very misleading.

Thr following is an illistrated discussion of the identification of five Western Australian trees.


Organo-Phosphorus Insecticides For Control Of Red-Legged Earth Mite And Lucerne Flea, J A. Button Jan 1966

Organo-Phosphorus Insecticides For Control Of Red-Legged Earth Mite And Lucerne Flea, J A. Button

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

MOUNTING CONCERN over residue problems arising from the use of D.D.T. and other chlorinated hydrocarbon insecticides on pasture has highlighted the need for alternative chemicals capable of providing satisfactory control without undesirable side effects.


Continuous Grazing On Rose Clover At Northampton, R J. Parkin Jan 1966

Continuous Grazing On Rose Clover At Northampton, R J. Parkin

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

BECAUSE of its upright growth habit, it is often thought that rose clover may require some form of specialised grazing management.

It has also been said that the sheep find the plant and in particular the seed head, undesirable in the dry stages.

However, more recent observations refute this (Bailey 1966). The present commonly-grown strains of rose clover are later flowering generally than the medics or Geraldton subterranean clover and stay green later in the season.


Individual Sow Feeders, P Mcnamara Jan 1966

Individual Sow Feeders, P Mcnamara

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

FOOD is the major cost in any pig enterprise and it is particularly easy for waste to occur in the breeding herd.

Individual feeders enable the pigman to feed each sow according to her need, and enable the sows to eat their feed slowly or quickly as they choose.


Citrus Red Scale Control, G D. Rimes Jan 1966

Citrus Red Scale Control, G D. Rimes

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

THE RED SCALE (Aonidiella aurantii Masc.) is widely distributed throughout the world and is a serious pest in countries with semi-arid climates such as California, South Africa, Palestine and Australia.

The home of the pest is probably China, but it has been known in Australia for over 70 years and it was introduced into North America from the continent.


Termites Or White Ants, Clee Francis Howard Jenkins Jan 1966

Termites Or White Ants, Clee Francis Howard Jenkins

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

TERMITES are commonly but erroneously called "white ants."

Actually they are more nearly related to cockroaches than to ants, but their general appearance and subterranean habits have given strong support to the popular designation.

They may be divided into two major groups from an economic point of view, viz., wood-dwelling and earth-dwelling termites.


Stoneville Horticultural Research Station : Ten Years Of Progress, Frank Melville Jan 1966

Stoneville Horticultural Research Station : Ten Years Of Progress, Frank Melville

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

THE Stoneville Research Station is a tree fruit station situated in the Darling Ranges 25 miles north east of Perth.

Climatically it is similar to the Hills fruit districts adjacent to Perth and is suitable for the growing of apples, pears and most stone fruits.

Citrus fruits can also be grown moderately well.


Strains Of Stem And Leaf Rust On Wheat In Western Australia Since 1951, I A. Watson, W. P. Cass Smith, W. A. Shipton Jan 1966

Strains Of Stem And Leaf Rust On Wheat In Western Australia Since 1951, I A. Watson, W. P. Cass Smith, W. A. Shipton

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

THE most important wheat rust in Western Australia is stem rust,

Leaf rust occurs infrequently and has not been known to cause serious damage.


Pasture Seed Production, 1966 : Statistics And Comments, B J. Quinlivan Jan 1966

Pasture Seed Production, 1966 : Statistics And Comments, B J. Quinlivan

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

THE marketing of pasture seeds differs from that of some other primary products in that there are no guaranteed prices.

A knowledge of potential supply and demand for the various species and strains is just as important to the seed producer as good production techniques.


Stop-Drop Sprays For Jonathan And Delicious Apples, N H. Shorter, J. Cripps Jan 1966

Stop-Drop Sprays For Jonathan And Delicious Apples, N H. Shorter, J. Cripps

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

STOP-DROP sprays prevent excessive pre-harvest drop of Jonathan and Delicious apples.

Recent research has thrown more light on the best methods of employing these materials.

TWO CHEMICALS used as "stop-drop" sprays are available commercially in Western Australia. One of these, alpha napthalene acetic acid (NAA), is also well known as a thinning spray for apples.


Values Of Commonly-Used Protein Supplements In Broiler Rations, D F. Hessels Jan 1966

Values Of Commonly-Used Protein Supplements In Broiler Rations, D F. Hessels

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

THE performances of broiler flocks in the latter part of 1964 were below standard. Low body weights and a high incidence of gizzard erosion were common on farms.

It was therefore decided to test the biological valuss of the commonly-used protein supplements and also to try to find a correlation between gizzard erosion and any of the protein supplements.


South Dakota Farm And Home Research, Agricultural Experiment Station Jan 1966

South Dakota Farm And Home Research, Agricultural Experiment Station

South Dakota Farm and Home Research: 1949 -1998

Contents:
The Electric Computer- Friend or Foe? [p] 4
Artificial Environments to Study Flax Yield, Maturity, Oil Quality. [p] 8
South Dakota Raccoons. [p] 12
Bigmouth Buffalo as Protein Source. [p] 15
Corn and Sorghum Silages Fortified with Soybeans [p] 16
New Small Varieties of Small Grains [p] 19
Laundry Research Looks for Cleaner, Brighter Clothes [p] 22
Water on South Dakota Rangelands [p] 24
Pros and Cons of Growing Crambe. [p] 27
South Dakotans, U.S.A. [p] 27
Irrigating by Radio [p] 28
1966 Family Living Outlook [p] 31


Pheremones In Trailmaking, Roxanna Young Jan 1966

Pheremones In Trailmaking, Roxanna Young

Student Scholarship

The paper explores the complex systems of chemical communication utilized by insects, with a specific focus on the role of pheromones in the trailmaking behavior of foraging ants. Unlike hormones that act internally, pheromones are secreted externally to influence the behavior or physiology of other members of the same species. These substances are categorized into two functional groups: releaser pheromones, which trigger an immediate behavioral response via the central nervous system, and primer pheromones, which induce slower physiological changes in the recipient. 

Foraging in ant colonies typically involves a transition from exploratory scouting to organized trailing. When a scout discovers …


The Gross And Microscopic Anatomy Of The Ducts Connecting The Testis And Epididymis In The Mouse, Bruce F. Lindgren Jan 1966

The Gross And Microscopic Anatomy Of The Ducts Connecting The Testis And Epididymis In The Mouse, Bruce F. Lindgren

All Graduate Theses, Dissertations, and Other Capstone Projects

In man and other mammals including the mouse, spermatozoa are produced in the testis. Before they are mature, spermatozoa leave the testis and pass through a system of excurrent ducts where they acquire an enhanced capacity for fertilization (Young, 1931; Blandau and Rumery, 1961). These ducts include the tubuli recti, rete testis, ductuli efferentes, ductus epididymidis, and ductus deferens. The contribution of individual parts of this excurrent duct system to spermatozoan maturation is poorly understood.

This study was undertaken to describe the gross and microscopic anatomy of the tubuli recti, rete testis, ductuli efferentes, and their proximal and distal connections …


Linuron : A New Herbicide For Cereal Crops, Geoffrey A. Pearce Jan 1966

Linuron : A New Herbicide For Cereal Crops, Geoffrey A. Pearce

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

DURING two years of trials on both pastures and cereals Linuron has proved itself to be a valuable addition to the range of chemicals for the control of weeds in cereals.

It has a good crop tolerance safety factor and controls a wider range of weeds than most other herbicides.


Additional Information On Basicladia Crassa Hoffmann And Tilden, Robert G. Anderson, Clarence B. Sinclair Jan 1966

Additional Information On Basicladia Crassa Hoffmann And Tilden, Robert G. Anderson, Clarence B. Sinclair

Journal of the Arkansas Academy of Science

No abstract provided.


Heat Resistance Experiments With The Longear Sunfish, Lepomis Megalotis (Rafinesque), William H. Neill, Kirk Strawn, James E. Dunn Jan 1966

Heat Resistance Experiments With The Longear Sunfish, Lepomis Megalotis (Rafinesque), William H. Neill, Kirk Strawn, James E. Dunn

Journal of the Arkansas Academy of Science

No abstract provided.


An Ecological Study Of Aspen Forest Communities, Kimball T. Harper Jan 1966

An Ecological Study Of Aspen Forest Communities, Kimball T. Harper

Aspen Bibliography

No abstract provided.


Influence Of Fire On Aspen, K. W. Horton, E. J. Hopkins Jan 1966

Influence Of Fire On Aspen, K. W. Horton, E. J. Hopkins

Aspen Bibliography

No abstract provided.


Review Of Silvicultural Research: White Spruce And Trembling Aspen Cover Types, Mixedwood Forest Section, Boreal Forest Region, Alberta-Saskatchewan-Manitoba, J. M. Jarvis, G. A. Steneker, R. M. Waldron, J. C. Lees Jan 1966

Review Of Silvicultural Research: White Spruce And Trembling Aspen Cover Types, Mixedwood Forest Section, Boreal Forest Region, Alberta-Saskatchewan-Manitoba, J. M. Jarvis, G. A. Steneker, R. M. Waldron, J. C. Lees

Aspen Bibliography

The Department of Forestry has been carrying on silvicultural research in the white spruce (Picea glauca (Moench) Voss) and trembling aspen (Populus tremuloides Michx.) cover types in the Mixedwood Forest Section of Alberta, Saskatchewan and Manitoba for about 40 years. Because of the needs of industry most of this research has been focused on spruce, and only as small portion on aspen. Much of the research is concerned with basic problems and the findings in one area may be applied directly or with minor modification throughout the entire Mixedwood Forest Section. Only a minor part of the total …


The Comparative Osteology Of The Skulls Of Three Species Of Paralichthys, Family Bothidae, Anne Caperton Beirne Jan 1966

The Comparative Osteology Of The Skulls Of Three Species Of Paralichthys, Family Bothidae, Anne Caperton Beirne

Master's Theses

This study was undertaken to determine if there were osteological variations in the skulls of young summer flounders, Paralichthys dentatus (Linaeus), southern flounders, Paralichthys lethostigma Jordan and Gilbert and - gulf flounders, Paralichthys albigutta Jordan and Gilbert that could be used as bases of species separation. As two of the species (dentatus and lethostigma) are of considerable economic importance, it would be of substantial value to establish skeletal characters that would help identify the young and. subsequently aid in determining their particular habitats where they occur in the same area.The three are closely related and difficult to recognize unless the …


The Effects Of Single-Dose X-Irradiation On Melanocytes In The Leg Musculature And Skin Of The Pet Mouse, Barry Eckert Schaeffer Jan 1966

The Effects Of Single-Dose X-Irradiation On Melanocytes In The Leg Musculature And Skin Of The Pet Mouse, Barry Eckert Schaeffer

Master's Theses

While most investigations have been limited to the study of pigment cells in the epidermis and hair follicles, this work embraces pigmentation of the leg muscles and dermis as well. To this end, PET mice were used which have an abundance of pigment cells in the leg muscles, but which show restriction of integumentary melanocytes to the dermis and hair. This characteristic provided the unique opportunity of comparing isolated systems of pigment cells in their response to identical stimuli of x-rays. Because pigment cells originate in the neural crest early in development and migrate throughout the embryo, all pigment cells …


Ixodid Ticks: Possible Vectors Of Tuberculosis, Ya. A. Blagodarnyy, I. N. Blekhman, M. P. Yukunin Jan 1966

Ixodid Ticks: Possible Vectors Of Tuberculosis, Ya. A. Blagodarnyy, I. N. Blekhman, M. P. Yukunin

United States Navy: Publications

"From these tests, we established that artificially and naturally fed ticks are susceptible to the infective source and preserve tuberculosis mycobacteria in the body for a long period."


Some Helminths Of Itasca Park Fishes, Omer R. Larson Jan 1966

Some Helminths Of Itasca Park Fishes, Omer R. Larson

Journal of the Minnesota Academy of Science

A helminth survey was conducted'. on 12 species of fish taken from the waters of Itasca State Park. An abundant and varied helminth fauna was found, with 3 l parasitic forms identified to genus or species. By taxonomic groups these included, 20 trematodes, 5 cestodes, 2 acanthocephalans, and 4 nematodes. Every fish examined was parasitized, but yellow perch and rockbass possessed the greatest variety of helminths. Based on the results of this survey, several aspects of parasite life cycles, geographic distribution, and hast specificity are discussed.


A Sick Ewe Why? [Pregnancy Toxaemia], F C. Wilkinson Jan 1966

A Sick Ewe Why? [Pregnancy Toxaemia], F C. Wilkinson

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

THIS dazed-looking ewe was seen wandering aimlessly around with an unsteady gait.

Three other ewes had died after a similar sickness lasting about four days.

Two more sheep in the flock of 350 ewes were also sick. One of them was down with its head on one side.