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Public Response To "Guidelines For Managing Aspen", Norbert V. Debyle

Aspen Bibliography

No abstract provided.

Management Overview, J.R. Jones, R.P. Winokur, W.D. Shepperd

Aspen Bibliography

No abstract provided.

Effects Of Water And Temperature In Aspen: Ecology And Management In The Western United States, J.R. Jones, Merrill R. Kaufmann, E.A. Richardson

Aspen Bibliography

No abstract provided.

Universal Time Dependence Of Nighttime F Region Densities At High Latitudes, O De La Beaujardiere, Vincent B. Wickwar, G Caudal, J Holt, J D. Craven, L A. Frank, L Brace, D Evans, J D. Winningham, R A. Heelis

All Physics Faculty Publications

Coordinated EISCAT, Chatanika, and Millstone Hill incoherent scatter radar observations have revealed that in the auroral zone, the nighttime F region densities vary substantially with the longitude of the observing site: EISCAT’s densities are the largest and Millstone Hill’s are the lowest. The nighttime F region densities measured by the individual radars are not uniform: the regions where the densities are maximum are the so-called “blobs” or “patches” that have been reported previously. The observations are consistent with the hypothesis that the nighttime densities are produced in significant amounts not by particle precipitation, but by solar EUV radiation, and that …

Comparison Of Bootstrap And Jacknife Statistical Procedures, Amanuel Gobena

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report compares the bootstrapping to jacknifing statistical procedures in terms in bias, confidence interval and estimation of median. Related literature have been reviewed. A bootstrap allows a researcher to get an approximation to the distribution of possibly complicated statistical summaries. It is based on random sampling with replacement from experimental units. Jacknife has also been in operation prior to bootstrapping statistical procedure. The jacknife divides the data into subgroups and obtains partial estimates of these subgroups by omitting one subgroup at a time. When both of these statistical resampling procedures are compared the bootstrap has less bias, more accurate …

Microstructure Of Meat Emulsions In Relation To Fat Stabilization, Chong M. Lee

Food Structure

No abstract provided.

Ultrastructural Studies On The Cultivation Processes And Growth And Development Of The Cultivated Mushroom Agaricus Bisporus, D. A. Wood, G. D. Craig, P. T. Atkey, R. J. Newsam, K. Gull

Food Structure

Scanning electron microscopy (SEM) , transmission electron microscopy and light microscopy have been used to study various processes in the cultivation of the edible mushroom Agaricus bisporus . Mushrooms are cultured on composted wheat straw. The microbial degradation processes during composting have been visualised by TEM and SEM and correlated with microbiological studies . Various modes of attack by the microorganisms on the plant cell walls can be seen. Most rapid degradation occurred on the cuticle and phloem and spread to other cell types. Microbial attack was found to be nonuniform between tissue types and individual cells. The mycelium of …

Cryoultramicrotomy And Electron Microanalysis Of Isolated Bovine Adrenal Chromaffin Cells, Richard L. Ornberg

Scanning Electron Microscopy

Instrumentation and techniques have been developed for the cryoultramicrotomy of isolated bovine adrenal chromaffin cells frozen with a liquid helium cooled copper block method. X-ray microanalysis and electron energy loss spectroscopy were used to measure both light and heavy element content of the adrenal storage granule, the chromaffin granule. Ultrathin freeze-dried cryosections usually have a fine compression which in cellular structure compresses the cytoplasm between organelles. Nuclei, chromaffin granules, and vacuoles are relatively free of compression. The mechanism for this distortion is not known al though static charge induced sticking to the knife may be the most probable cause.

The …

The Size Distribution Of Bovine Casein Micelles: A Review, C. Holt

Food Structure

This review considers the average size and size distribution of bovine casein micelles as measured by electron microscopy, light scattering and controlled pore glass chromatography, and the origin and biological function of the size distribution.

Recent work by electron microscopy has given average sizes in reasonable agreement with measurements on the same milk sample by light scattering . It is suggested that natural variations in averaqe micelle size and overestimation of micelle radii by light scattering methods as well as deficiencies in electron microscopical methodology were responsible for past discrepancies.

Electron microscopy and controlled pore glass chromatography provide evidence that …

Structure Of Coarse And Fine Fractions Of Corn Samples Ground On The Stenvert Hardness Tester, Y. Pomeranz, Z. Czuchajowska

Food Structure

Kernels from a pair of isogenic lines (with regard to hardness) and two commercial hybrids of dent corn (that varied in hardness) were ground on the Stenvert Hardness Tester and separated by sieving into coarse (>0.710 mm) and fine (<0.500 mm) fractions. The corn samples differed little in oil contents. The coarse particles from the hard corn samples were angular and sharp-edged; those from the soft corn samples were rounded. The yield of coarse particles was higher and they contained less oil in hard than in soft corn. Fine particles from all four corn samples had higher oil content than the coarse particles. Visual examination, observation at low magnification under a light microscope, and use of a scanning electron microscope revealed consistent differences in the extent and mode of corn kernel breakdown during grinding. Particles in the coarse fraction from hard kernels were to a large extent intact with little exposure of their contents. In the soft kernels, particles in the coarse fraction were broken extensively and their contents exposed. It is postulated that differences in the extent of mechanical breakdown and oil content are related to differences in shelf life of corn grits.

Thermal Analysis Microscopy For The Study Of Phase Changes In Fats, J. M. Deman, A. N. Mostafa, A. K. Smith

Food Structure

An investigation was carried out using the Mettler FPBOO Thermosystem to study polymorphic transitions of several monoacid triglycerides and hydrogenated Canola oil. The system includes a central processing unit connected with a thermal microscopy hot stage that allows the measurement of heat flow to the scrnple . Scanning electron microscopy was also used to examine the same samples after osmium tetroxide fixation . The results obtained relate phase transitions occurring during heating and cooling with the morphology of the various crystal structures.

Ultrastructural Ultilization Of Plants By Herbivores, L. H. Harbers

Food Structure

Study of the patterns of ruminal digestion of forages enhances the nutritional knowledge of how specific plant tissues are digested and adds its own dimension by characterizing the specific cells and the complex interactions of ruminal microflora with those tissues. A common pattern of digestibility exists for mono- and dicotyledon leaves: mesophyll and phloem are degraded readily, and sclerenchyma slowly, whereas cuticle and the remaining vascular tissues are rarely utilized . Digestion of stems is limited to parenchymal tissues in monocotyledons and to cortex and parenchyma in dicotyledons. Epidermal silica and cuticle are undigestible and restrict microbial entrance. Calcium oxalate …

Relation Between Microstructure, Destabilization Phenomena And Rheological Properties Of Whippable Emulsions, W. Buchheim, N. M. Barfod, N. Krog

Food Structure

The structure of spray-dried whippable emulsions (toppings) containing different types of lipid surfactants, was investigated by electron microscopy using the freeze-fracture technique. The size distribution of the lipid particles within the powders varied with the type of the surfactant used. After reconstitution of the topping powders in water. a strong destabilization phenomenon took place to an extent depending on the type of the surfactant. Simultaneously a crystallization of coalesced lipid particles occurred along with an increase in viscosity of the emulsions. The degree of crystallization was measured by p-NMR. It has been concluded that these phenomena are closely related to …

Scanning Electron Microscopic Study Of Rockfish Preserved At Either Ambient Temperature Or By Isothermal Freeze-Fixation, L. E. Lampila, V. Mohr, D. S. Reid

Food Structure

Fresh rockfish (Bocaccio, Sebastus paucispinis) fillets were blast frozen and stored at either -5 °C or -20 °C for 60 days . At defined sampling intervals, speci mens were removed and chemically fixed at either ambient temperature or isothermally, at the respective storage temperatures (-5 °C or -20°C) . The results indicated that isothermally freeze - fixed specimens showed a degree of crushing and/or distortion of the muscle fiber, the deposition of presumed ice crystals in the cell membrane, the multi-dimensionality of connective tissue and the preservation of fine detail . In specimens fixed at ambient temperatures , structura l …

Changes In Typical Organelles In Developing Cotyledons Of Soybean, K. Saio, K. Kondo, T. Sugimoto

Food Structure

Soybean cotyledonary cells harvested every 5-10 days at 15 to 60 days after flowering (OAF), were investigated by means of light and transmission electron microscopy. In the early developing stages (15-20 OAF) most of the cells were occupied by large, centrally located vacuoles while the cytoplasm was restricted to a thin layer against the cell wall and contained numerous ribosomes, mitochondria, plastids, small amounts of endoplasmic reticulum (ER) and minute lipid bodies. At about 25 OAF, spherical organelles which contained protein, lipid and sugar (PLS bodies), appeared and then increased in number and in size. Vacuoles had protein deposits lining …

Early Research On The Fibrous Microstructure Of Meat, H. J. Swatland

Food Structure

The older scientific literature on the histology of skeletal muscle describes the trans verse fragmentation of myofibrils to form sarcomere disks and the attachment of Z lines to the sarcolemma in contracted muscle. These phenomena may now be explained by recent research on the cytoskeletal framework of muscle fibers, particularly desmin and vinculin. The formation of sa rcomere disks might be developed as a simple method to study cytoskeletal integrity in meat. In early research, contraction bands and the disappearance of transverse striations during contraction caused considerable confusion with ordinary light microscopy. These problems were largely resolved by the use …

The Combined Effects Of The Calcium Activated Factor And Cathepsin D On Skeletal Muscle, E. A. Elgasim, M. Koohmaraie, A. F. Anglemier, W. H. Kennick, E. A. Elkhalifa

Food Structure

Myofibrils were isolated from atdeath ovin elongissimus muscles and incubated with crude calcium activated factor prepared from the same muscle and with purified cathepsin D. Myofibrils we reincubated with these enzymes separately (first incubation) and successively (second incubation). The major changes induced by cathepsin D first incubation include degradation of myofibrillar proteins with molecular weight > 200 K, myosin, actin, troponin- T and troponin 1. Also new bands appeared at the 140- 160 K, 80 K, 68 K and 30 K regions. Similar changes were obtained 1v hen myofibrils were incubated first with CAF then with cathepsin D (second incubation). On …

Ultrastructural And Biochemical Investigations Of Mature Human Milk, Robert J. Carroll, Jay J. Basch, John G. Phillips, Harold M. Farrell Jr.

Food Structure

The casein complexes (casein micelles) of human skim milk were evaluated by electron microscopy. Fourteen samples of human milk were obtained from seven donors whose stage of lactation varied from 1 to 23 months. Compositional and biochemical parameters were measured to evaluate the nature of these samples. For mature human milks, 2-13 months of lactation, average percentage of solids-notfat was found to be 8.32 ± 0.16. Protein compositions of the skim milks were studied by the Coomassie blue dye binding method and by SDS-gel electrophoresis; total protein and casein were found to be 0.62 ± 0.18 and 0.29 ± 0.02 …

The Light Microscopy Of Triglyceride Digestion, John S. Patton, Russel D. Vetter, Margit Hamosh, Bengt Borgstrom, Mats Lindstrom, Martin C. Carey

Food Structure

During fat digestion (lipolysis) a number of physiochemical events can be seen directly by light microscopy. Hydrolysis of emulsified fat droplets bylipases at pHs above about 6.5 proceeds with the formation of visible product phases that may include both crystalline as well as liquid crystalline phases. The crystalline phase is primarily calcium-fatty acid soap and its formation is favored by high calcium concentrations, alkaline pHs, and inhibited by low pH and monoglycerides. The formation of liquid crystalline product phases are favored by low calcium-concentrations. monoglycerides and lipid saturated bile salt solutions. Both phases are solubilized by bile salts but the …

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 …

Seed Microstructure: Review Of Water Imbibition In Legumes, Barry G. Swanson, Joe S. Hughes, H. Paul Rasmussen

Food Structure

Scanning electron microscopy (SEM) is an invaluable tool for studying foods and food products. SEM has been particularly va luable in the study of seed microstructure and the ro le of microstructure in water imbibition by legumes. Controversy continues to surround the causes of hard ness in legumes as addi tional research revea ls differences between legumes that imbibe water and legumes that fail to imbibe water. SEM observation of the microstructural changes occurring in legumes during water imbibition ofkrs a better undcrstandi ng of d i ffc rcnces that ex ist betwee n hard and normal beans. Structural changes …

Comparison Of The Microstructure Of Firm And Stem-End Softened Cucumber Pickles Preserved By Brine Fermentation, W. M. Walter Jr., H. P. Fleming, R. N. Trigiano

Food Structure

Soft and firm stem end tissues of cucumbers fermented at a low concentration of sodium chloride were examined by a combination of light microscopy {LM), transmission electron microscopy { TEM), and scanning electron microscopy { SEM) . When compared to firm tissue, softened tissue cell walls were swollen and striated, and the middle lamellae were poorly stained by the uranyl acetate-1 ead citrate used in TEM . When the tissue was penetrated by a circu l ar punch {1.5 mm diameter), cells in soft tissue tore along the middle l arne ll ae rather than across cell walls, as did …

A Fluorescence Microscopic Study Of Cheese, S. H. Yiu

Food Structure

Fluorescence techniques were used to study the microstructure of several varieties of cheese. The size and distribution of fat globules in various cheeses were demonstrated by fluorescent staining using Nile Blue A as a marker. Acridine Orange was used as a dye to detect structural differences between casein matrices of various cheese varieties. Differences between the ripe and the less- ripe zones of Ca membert cheese were detected by staining the cheese sections with Acridine Orange and Nile Blue A separately, and then comparing the re sults of the stainings. The Nile Blue A stain ing s howed that fat …

Structure Formation In Acid Milk Gels, I. Heertje, J. Visser, P. Smits

Food Structure

The structure formation in acid milk gels is influenced by many factors such as heat, salt system, pH, culture and thickening agents. Understanding of the mechanism of structure formation is important in order to be able to influence the final texture of these products.

In the present study the network formation in acid milk gels during acidification is monitored by freeze-fracture electron microscopy. Network formation appears to be a much more complex process than just an aggregation of the original milk casein micelles; it is accompanied by subtle dissociation and association phenomena of the milk caseins. The observed sequence of …

Effect Of Ionizing Irradiation And Storage On Mushroom Ultrastructure. I. The Gills Of Agaricus Bisporus (Lge.) Imbach And Pleurotus Ostreatus (Jacq. Ex Fr.) Kummer, A. Keresztes, J. Kovacs, E. Kovacs

Food Structure

We have investigated the gills of both the control and gamma-irradiated groups of A.bisporus and P.ostreatus (2.5 kGy or 2.5 and 5.0 kGy doses, respectively) by scanning (SEM) and transmission (TEM) electron microscopy. The primary aim of our study was to see, how gamma-irradiation used for shelflife extension inhibits spore production. We have found in both species that inhibition of spore production in irradiated specimens is caused by the destroying of basidia rather than by retarding normal spore development. In P.ostreatus the hymenium appears to be more sensitive to irradiation than in A.bisporus. In both species the subhymenium and trama …

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. …

Acidification Sources In Red Alder And Douglas-Fir Soils -- Importance Of Nitrification, H. Van Miegroet, D. W. Cole

Watershed Sciences Faculty Publications

Precipitation, throughfall, forest floor, and soil leachate samples were monitored continuously in 1981 and 1982 in a N-poor Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] forest and a red alder (Alnus rubra Bong.) forest growing adjacently on a glacial soil in western Washington. The purpose of the study was to quantify the relative importance of atmospheric vs. natural sources of H+ input to forest soil acidification, and to determine the role of N transformation processes in the overall H+ balance of soils with different N status. Rainwater samples had an avg pH of 4.7 and annual H+ deposition via precipitation averaged 320 …

Evaluation Of Miramat Under High Velocity Flows, C. Earl Israelsen, Frank W. Haws

Reports

Introduction: Newly constructed earth channels and steep cut and fill slopes on construction projects need temporary protection from water erosion until a protective cover of vegetation can be grown. In some instances the temporary protective measures can be left in position to serve as part of the permanent system. Various kinds of vegetative and chemical mulches are available for use as temporary control measures, and other materials such as jute, fiberglass roving, and excelsior blanket are also in use. However, for large volumes of flow and for high velocities, more substantial materials are required. One class of such materials is …

Identification And Modeling The Impact Of Marine Shale Bedrock On Groundwater And Stream Salinity: Upper Colorado River Basin, Christopher J. Duffy, Jerome J. Jurinak, Sanjay Sangani, Ali Azimi

Reports

Recent studies have shown that groundwater is a major contributor to stream salinity in the Upper Colorado River Basin. The primary salt sources are the marine shales and shale residuum that underlie the soils of much of the basin. A field site in the Price River Basin, a tributary to the Green and Colorado Rivers, was selected to study the physical and chemical factors that control the interactions between groundwater and these shales. Preliminary data were available at the site as a result of a Bureau of Reclamation study conducted by CH2M Hill. On the basis of the CH2M Hill …

Water Education ... With Emphasis On Deer Creek Reservoir - Provo River Drainage Area (Grades 5-8), Donald R. Daugs, C. Earl Israelsen, Mardell C. Parrish

Reports

Introduction: The major goals of this publication are to: * promote an awareness of the importance of water resources associated with the target watershed; * provide teachers with learning resources which are easily used in the classroom or in the field; and * provide teachers with teaching materials which help satisfy State Core Standards.