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Characterisation Of Milk Proteins In Confectionery Products, J. F. Heathcock Jan 1985

Characterisation Of Milk Proteins In Confectionery Products, J. F. Heathcock

Food Structure

The proteins from milk play an important part in the structural properties of confectionery products. These properties will in turn influence texture and flavour. Electron microscopy techniques have been used to examine milk chocolate, caramel and fudge and to locate and characterise the milk proteins within their structures. Following scanning electron microscopy examination of the products at low temperature, thin sectioning and freeze-fracture were used to resolve the fine ultrastructure of casein and whey proteins.

A chocolate prepared from milk crumb could be distinguished from one made with a dry milk powder on the basis of a more even distribution …


Particle Structure In Spray-Dried Whole Milk And In Instant Skim Milk Powder As Related To Lactose Crystallization, Zenichi Saito Jan 1985

Particle Structure In Spray-Dried Whole Milk And In Instant Skim Milk Powder As Related To Lactose Crystallization, Zenichi Saito

Food Structure

The structure of instant skim milk and whole milk powders was studied by scanning electron microscopy with special respect to lactose crystallization during storage. X-ray diffraction analysis was used to confirm the crystallization. Some samples were ashed in a plasma asher and the residues were also examined by scanning electron microscopy. The structures of instant skim milk and whole milk powder particles were well-preserved after the ashing procedure.

The crystallization of ~X-Iactose hydrate occurred in instant skim milk and whole milk powders according to moisture uptake. In instant skim milk powder, ~X-Iactose hydrate crystals were observed on the particle surface. …


The Application Of Light And Scanning Electron Microscopy During Flour Milling And Wheat Processing, R. Moss Jan 1985

The Application Of Light And Scanning Electron Microscopy During Flour Milling And Wheat Processing, R. Moss

Food Structure

Light and scanning electron microscopy have been employed as part of an on-going study on the effect of the milling system on flour composition and quality. Examples are given of some areas where microscopy has been particularly useful in understanding the functional changes that take place during milling or the subsequent processing of the flour . The use of heavy reduction roll pressures was shown to modify gluten protein quality as well as produce the desired increase in starch damage. The use of in-line impact machines not only disrupted flaked flour particles but also fragmented wheat germ and allowed it …


Microstructure Of Spray-Dried And Freeze-Dried Microalgal Powders, L. P. Lin Jan 1985

Microstructure Of Spray-Dried And Freeze-Dried Microalgal Powders, L. P. Lin

Food Structure

Chiarella and Spirulina algae were spray-dried and freezedried under several different conditions, and the morphological changes induced were studied by scanning electron microscopy. The internal structure of the particles (granules) was revealed by cryofracturing. The cellular composition of the two algae, method of drying, cell concentration, feed conditions, temperature, and drying times all affected the external morphology of the resulting powders. In the case of spray-drying, at a temperature of 160 °C for 6 sec, the particles shrunk or collapsed; if the drying time was over 10 sec at 160 °C, similar results were observed. The cell concentration affected the …


Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois Jan 1985

Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

RESUMEN:

Histológicamente, las gónadas de Chthonerpeton indistinctum son similares a las ya descritas para otras especies del orden Gymnophiona. Los lóbulos testiculares se hallan compartimentados en unidades estructurales denominadas lóculos. La espermatogénesis ocurre en cistos sincrónicos de células germinales. Durante la espermiogénesis se identifican cuatro estados consecutivos de desarrollo: 1) cistos de espermátidas redondeadas; 2) cistos de espermátidas arrifionadas; 3) cistos de espermátidas bastoniformes y 4) espermátidas en ramillete.

El análisis histológico de los ovarios mostró la presencia de tres estados en la maduración de los folículos ováricos. Estas etapas pueden ser identificadas de acuerdo a: 1) ubicación del folículo …


A Key To The Australian Chrysis With Description Of New Species(Hymenoptera: Chrysididae), Richard M. Bohart Jan 1985

A Key To The Australian Chrysis With Description Of New Species(Hymenoptera: Chrysididae), Richard M. Bohart

Insecta Mundi

Australian Chrysis form three closely related groups in addition to a few wide-ranging and apparently adventive species. The latter are lincea Fabricius, schiodtei Dahlbom, fuscipennis Brulle, and fossulata F. Smith. The remaining 23 species, including those presently described, appear to be endemic i n the Australia-New Guinea area. Recently, Linsenmaier (1982, Entomofauna 3: 323-349) described a number of new species from Australia. Some of these I have been able to recognize and they are included in the key. Others that I am unable to place, possibly through lack of material, are curtisensis from Queensland and dentifrontis from South Australia. I …


Covers Volume 1 Jan 1985

Covers Volume 1

Insecta Mundi

Volume 1 Covers


Regeneration In Aspen: Ecology And Management In The Western United States, George A. Schier, Wayne D. Shepperd, John R. Jones Jan 1985

Regeneration In Aspen: Ecology And Management In The Western United States, George A. Schier, Wayne D. Shepperd, John R. Jones

Aspen Bibliography

No abstract provided.


Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois Jan 1985

Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

La morfología e histología del ovario para varias especies del orden Gymnophiona ha sido reportada por Wake (1968, J. Morphol. 126, 291) y para C. indistinctum por los autores (1984, XXIV Reunión de Comunicaciones, Soc. Zool. Uruguay).

Continuando con los estudios sobre el aparato genital de esta especie vivípara, se presenta ahora la estructura del ovario durante la gestación.

Se procesaron con fines histológicos, ovarios de dos hembras grávidas colectadas en las costas de los Dep. Montevideo y San José en abril, 1983. El número de ejemplares trabajados es muy reducido dado lo difícil que resulta su colecta …


Some Effects Of Viterra 2 Hydrogel On Soil Physics And Plant Growth, Julia E. Maserang Jan 1985

Some Effects Of Viterra 2 Hydrogel On Soil Physics And Plant Growth, Julia E. Maserang

Masters Theses

The effects of hydrogel on various aspects of plant growth and soil physics were determined for Tagetes patula (marigold) and Vinca rosea growing in 'PRO-MIX' soilless potting medium.

The addition of hydrogel at various concentrations to the potting medium increased the water-holding capacity of the medium, thus extending the hours-to-wilt of plants growing in this medium. While hydrogel had no effect on plant height, flowering time, plant color, soil pH or soil nitrate concentration, plant weight and flower number did appear to increase between the control and highest hydrogel treatment. As hydrogel concentration within the medium increased, percent total seed …


Fecal Coliform Membrane Filtration Recovery Techniques, Pamela Rose Rinebold Jan 1985

Fecal Coliform Membrane Filtration Recovery Techniques, Pamela Rose Rinebold

Masters Theses

Researchers over the years have been trying to improve recovery techniques for fecal coliform bacteria. Improved techniques would provide better estimates of the number of fecal coliform bacteria as well as better estimates of fecal contamination with potential pathogenicity of food and water.

Stressed, but viable, fecal coliform bacteria if placed under the appropiate conditions, can recover, thus presenting the possibility of inadequate disinfection. Chlorine sanitization, as done in potable and wastewater treatment, is one such method of stressing bacteria.

Techniques of recovery were studied using presumably unstressed and chlorine stressed samples. Phase one of this study was the comparison …


Louisiana Agriculture Magazine, Winter 1985-1986, Lsu Agricultural Experiment Station Jan 1985

Louisiana Agriculture Magazine, Winter 1985-1986, Lsu Agricultural Experiment Station

Louisiana Agriculture

No abstract provided.


Identification Of Volatile Compounds Produced By Brevibacterium Linens That Inhibit Molds, Samuel E. Beattie Jan 1985

Identification Of Volatile Compounds Produced By Brevibacterium Linens That Inhibit Molds, Samuel E. Beattie

Electronic Theses and Dissertations

Mold contamination of processed food and its raw ingredients is a major concern in agriculture. Although at one time mold contamination of cheese and other foods was considered to be of little conse9uence, discovery of carcinogenic and/or teratogenic toxins (73) produced by molds commonly associated with food has changed this innocuous and frequent inconvenience into a serious health consideration. The presence of mold on or in cheese is a common occurrence, indeed, many cheeses depend upon molds to provide characteristic cheese flavor and texture. Cheeses such as blue, Roquefort, Camembert, and Brie are ripened under controlled conditions by species of …


The Biological Role Of Sialosyl Transferase Activity In Rat Brain, Robert Paul Durrie Jan 1985

The Biological Role Of Sialosyl Transferase Activity In Rat Brain, Robert Paul Durrie

Dissertations

No abstract provided.


The De Novo Biosynthesis Of Cytokinins By Cell-Free Extracts Of Baker's Yeast, Debra A. Tonetti Jan 1985

The De Novo Biosynthesis Of Cytokinins By Cell-Free Extracts Of Baker's Yeast, Debra A. Tonetti

Master's Theses

No abstract provided.


Comparative Study Of Lactate Dehydrogenase Activity In Diving And Nondiving Reptiles, Dennis A. Baeyens, Deborah Bursey, Robert Rountree Jan 1985

Comparative Study Of Lactate Dehydrogenase Activity In Diving And Nondiving Reptiles, Dennis A. Baeyens, Deborah Bursey, Robert Rountree

Journal of the Arkansas Academy of Science

The properties of lactate dehydrogenase (LDH) were examined in two snake species and one turtle species. The snakes used in the study were the semi-aquatic Nerodia rhombifera and the terrestrial Elaphe obsoleta, while Pseudemys scripta represented the turtle species. Our purpose was to compare the LDH activity of nondiving reptiles (Nerodia and Elaphe) with that of the well established diver Pseudemys. The kinetic properties of LDH and its susceptibility to inhibition by elevated pyruvate concentrations were investigated in the brain and heart of the three species. Brain and heart were chosen because they are highly aerobic tissues and therefore should …


Role Of Centriolar Matrix And Striated Rootlets In Centriolar Pairing And Orientation During Spermatogenesis In Hydractina Echinata, Maurice G. Kleve Jan 1985

Role Of Centriolar Matrix And Striated Rootlets In Centriolar Pairing And Orientation During Spermatogenesis In Hydractina Echinata, Maurice G. Kleve

Journal of the Arkansas Academy of Science

Transmission electron microscopy of the spermatogenic stages of the hydroid, Hydractinia echinata, reveals a series of complex structural and positional changes in the centrioles of spermatocytes and spermatids. The newly generated centriolar pairs of spermatocytes form an unusual four-centriole aggregate that persists until cell division. The distal centrioles of this aggregate are shrouded with a very dense matrix that accumulates after centriolar replication. This matrix facilitates the mechanical attachment between distal centrioles and microtubular nucleating satellites, striated rootlets and pericentriolar processes. The association of these accessory structures occurs sequentially and is repeated in spermatocytes and spermatids. An electron dense plaque, …


Growth Patterns In Some Vitamin Deficient Media Of Lactobacillus Species Isolated From Fermented Foods(รูปแบบการเจริญในอาหารที่ขาดวิตามินบางชนิด ของเชื้อ La..., Wongcare Jivatadavirute, Somboon Tanasupawat Jan 1985

Growth Patterns In Some Vitamin Deficient Media Of Lactobacillus Species Isolated From Fermented Foods(รูปแบบการเจริญในอาหารที่ขาดวิตามินบางชนิด ของเชื้อ La..., Wongcare Jivatadavirute, Somboon Tanasupawat

The Thai Journal of Pharmaceutical Sciences

Growth in five vitamin deficient media of 44 isolates of Lactobacillus species isolated from fermented foods was determined. Each media was without one of the following five vitamins, thiamine, folic acid, niacin, biotin, or riboflavin respectively. Five...


Cryogenic Preservation Of Semen From The Greater Sandhill Crane, George F. Gee, Murray R. Bakst, Thomas J. Sexton Jan 1985

Cryogenic Preservation Of Semen From The Greater Sandhill Crane, George F. Gee, Murray R. Bakst, Thomas J. Sexton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Frozen gene pools (semen or embryos) can provide a safe place for the storage of genetic material for many generations. Cranes (Grus spp.) are one of many species in need of gene pool protection. Of the seven species and four subspecies considered rare or endangered (Archibald et al. 1981), two, the whooping crane (G. americana) and the Mississippi sandhill crane (G. canadensis pulla), are part of captive propagation projects at the Patuxent Wildlife Research Center in Laurel, Maryland. Greater sandhill crane (G. c. tabida) semen cryopreservation, under study at Patuxent since 1976 (Sexton …


Modification Of Sand Fly Biting Behavior By Leishmania Leads To Increased Parasite Transmission, Raymond Beach, Gabriel Kjilu, Johannis Leeuwenberg Jan 1985

Modification Of Sand Fly Biting Behavior By Leishmania Leads To Increased Parasite Transmission, Raymond Beach, Gabriel Kjilu, Johannis Leeuwenberg

Harold W. Manter Laboratory of Parasitology: Library Materials

To attempt rodent-sand fly-rodent transmission of Leishmania major, laboratory-reared Phlebotomus doboscqi were fed on L. major-infected mice and then refed on uninfected mice 21 days later. Flies which refed either probed 1–2 times and took a full blood meal in less than 10 minutes or probed 3 or more times and took little or no blood during a period of 15 minutes or more. When dissected, 7 of 8 flies which experienced difficulty in obtaining a blood meal had flagellates in their cibaria, an observation supporting the hypothesis that parasites in this part of the alimentary canal modify normal …


Potential For Development Of Tolerance By Penicillium Digitatum And Penicillium Italicum After Repeated Exposure To Potassium Sorbate, Lisa L. Schroeder, Lloyd B. Bullerman Jan 1985

Potential For Development Of Tolerance By Penicillium Digitatum And Penicillium Italicum After Repeated Exposure To Potassium Sorbate, Lisa L. Schroeder, Lloyd B. Bullerman

Department of Food Science and Technology: Faculty Publications

Two strains of Penicillium digitatum and one strain of Penicillium italicum were exposed to various levels of sorbic acid and potassium sorbate, and the MICs were determined. Selected strains of the molds were then repeatedly exposed to subinhibitory levels of the compounds to determine whether increased tolerance might develop. The MIC of sorbic acid (pH 4.75) to P. digitatum was between 0.02 and 0.025%. The MIC of sorbate (pH 5.5) to two strains of P. digitatum and P. italicum was found to be between 0.06 and 0.08%. Increasing levels of sorbate resulted in increasing growth suppression of the molds. Populations …


Proliferation Of Schwann Cells Induced By Axolemmal And Myelin Membranes, Michael Paul Dinneen Jan 1985

Proliferation Of Schwann Cells Induced By Axolemmal And Myelin Membranes, Michael Paul Dinneen

Theses and Dissertations

Purified Schwann cells were cultured from neonatal rat sciatic nerve using a modification of the method of Brockes (Brockes, J.P. et al, Brain Res. 165(1979) 105-118). Schwann cells and contaminating fibroblasts were unambiguously identified using fluorescent antibodies to 2'3' cyclic nucleotide 3'-phosphodiesterase and the thy 1.1 antigen respectively. The Schwann cells were quiescent unless challenged with mitogens, They proliferated rapidly in response to the soluable mitogen, cholera toxin, or to membrane fractions from rat CNS or PNS, prepared by the method of DeVries (DeVries, G.H., J Neurochem, 40 (1983) 1709-1717). Mitogenic activity was present in both axolemmal and myelin enriched …


Dissection Of Microphage Activation Using T Cell Hybridoma Derived Lymphokines, William S. Futch Jr. Jan 1985

Dissection Of Microphage Activation Using T Cell Hybridoma Derived Lymphokines, William S. Futch Jr.

Theses and Dissertations

Macrophage phenotype/function can be modulated by various T-cell lymphokines (LK). The alteration of macrophage phenotype is a result of LK concentration, duration of exposure, and the level of macrophage activation when obtained from in vivo sources through elicitation by either sterile irritants or immune cellular mechanisms. In order to dissect macrophage activation into discrete signals T cell hybridomas were constructed by fusing HAT sensitive BW5147 cells with nylon-wool purified, con A stimulated T cells. The resulting T cell hybrids were screened for their ability to: (a) protect macrophages from the cytopathic effect of Naegleria; (b) induce class II MHC gene …


Partial Characterization Of The Extracellular Polysaccharides Produced By Mutants Of Rhizobium Leguminosarum And Rhizobium Trifolii, Lendell L. Cummins Jan 1985

Partial Characterization Of The Extracellular Polysaccharides Produced By Mutants Of Rhizobium Leguminosarum And Rhizobium Trifolii, Lendell L. Cummins

Masters Theses

Extracellular polysaccharides (EPS) are suspected to be involved in some aspect of the Rhizobium-legume symbiotic process. Extracellular polysaccharides produced by R. leguminosarum and R. trifolii mutants were isolated and partially characterized by gas chromatography, column chromatography, double diffusion, polyacrylamide gel electrophoresis, and immunoelectrophoresis.

The R. leguminosarum mutants, derived from strain 128C53, all are deficient in EPS production (exo-). Strain ANU54 is missing the symbiotic plasmid, while plasmid-containing strains ANU54 pJB5JI and ANU54 pBR1AN nodulate (nod+) peas and clover respectively, but do not fix nitrogen (fix-).

R. leguminosarum mutants produce an EPS that is similar to parental LPS in composition. …


Salinity Tolerance In Forage Grasses, Kent Alan Boyles Jan 1985

Salinity Tolerance In Forage Grasses, Kent Alan Boyles

Masters Theses

The effects of increased osmotic potentials on Reed Canarygrass (Phalaris arundinacea var Vantage), Tall Fescue (Festuca arundinacea var Kentucky 31), Orchardgrass (Dactylis glomerata var Potomac), Sudangrass (Sorghum sudanense var Sorghum x Ludo FS X3-2), Grain Sorghum (Sorghum vulgare var Dekalb 28), Smooth Bromegrass (Bromus inermis var Blair), Timothy (Phleum pratense var Climax), and Winter Barley (Hordeum vulgare var Barsoy) were studied. The greenhouse triplicated experiments were conducted in modified aerated Hoagland's number 2 nutrient solutions for a period of four weeks.

The germination of Winter Barley was not inhibited by osmotic potentials …


Fisheries Report No 71 - An Investigation Of The Mortality Of The Pearl Oyster, Pinctada Maxima, In Western Australia, Rand Dybdahl, David A. Pass Jan 1985

Fisheries Report No 71 - An Investigation Of The Mortality Of The Pearl Oyster, Pinctada Maxima, In Western Australia, Rand Dybdahl, David A. Pass

Fisheries Research Reports

A three year investigation into the cause of abnormally high mortality rates of the pearl oyster, Pinctada maxima, on the cultured pearl industry's lease sites in the North West of Western Australia was completed on 30 June 71983. The objective of this study was to determine environmental, physiological and pathological factors predisposing farm oysters to excessive Levels of mortality and, if possible, make recommendations to alleviate this problem.

As mass mortalities may have complex causes, complementary field and laboratory studies were instigated. The culture industry's method of collection, transportation and farm husbandry were examined. Environmental parameters were monitored. Various empirical …


Regulation Of Nitrate Reductase Activity In Soybeans, Luke Curtis Jan 1985

Regulation Of Nitrate Reductase Activity In Soybeans, Luke Curtis

Master's Theses

No abstract provided.


Factors Affecting Germ Tube Formation In Candida Albicans, Walter A. Tatarowicz Jan 1985

Factors Affecting Germ Tube Formation In Candida Albicans, Walter A. Tatarowicz

Master's Theses

No abstract provided.


Observations On The Adherence Of Bacteroides Bivius To Female Genital Tract And Oral Epithelial Cells, Susan V. Meade Jan 1985

Observations On The Adherence Of Bacteroides Bivius To Female Genital Tract And Oral Epithelial Cells, Susan V. Meade

Master's Theses

No abstract provided.


The Trinidad And Tobago/Venezuela Fishing Agreement, Zaleena K. Chin-Yuen-Kee Jan 1985

The Trinidad And Tobago/Venezuela Fishing Agreement, Zaleena K. Chin-Yuen-Kee

Marine Affairs Theses and Major Papers

The twin-island Republic of Trinidad and Tobago is situated adjacent to the Republic Of Venezuela such that at one point Trinidad is merely seven miles off the northeast coast of Venezuela. Fishing activities of nationals of each country in the waters of the other are therefore common and often lead to conflict. In an attempt to solve the fishing problem a fishing agreement was negotiated. It came into force in 1978 and expired in 1984 whereupon negotiations commenced once more in an attempt to achieve new accord. The fishing industries of both countries and the conflicts which led to the …