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Full-Text Articles in Life Sciences

Isolation Of Three Hexahydro-1,3,5-Trinitro-1,3,5-Triazine- Degrading Species Of The Family Enterobacteriaceae From Nitramine Explosive-Contaminated Soil, Christopher Kitts, Daryl P. Cunningham, Pat J. Unkefer Dec 1994

Isolation Of Three Hexahydro-1,3,5-Trinitro-1,3,5-Triazine- Degrading Species Of The Family Enterobacteriaceae From Nitramine Explosive-Contaminated Soil, Christopher Kitts, Daryl P. Cunningham, Pat J. Unkefer

Biological Sciences

Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third isolate, identified as Citrobacter freundii, partially transformed RDX and generated high concentrations of nitroso-RDX intermediates. All three isolates produced 14CO2 from labeled RDX under O2-depleted culture conditions. While all three isolates transformed HMX, only M. morganii transformed HMX in the presence of RDX.


Anthocyanin Pigments: Comparison Of Extract Stability, Alan Baublis, Art Spomer, M. Doleres Berber-Jimenez Nov 1994

Anthocyanin Pigments: Comparison Of Extract Stability, Alan Baublis, Art Spomer, M. Doleres Berber-Jimenez

Liberal Studies

Stabilities of anthocyanins from Concord grapes, red cabbage, tradescantia and ajuga were studied. RP-HPLC analysis was used to characterize individual anthocyanins and spectrophotometric analysis for all pigments. Anthocyanins from tradescantia were much more stable than the other extracts. Such increased stability was attributed to its intrinsic nature.


Sensitivity Of Second Harmonic Generation To Space Charge Effects At Si(111)/Electrolyte And Si(111)/Sio2/Electrolyte Interfaces, P. R. Fischer, J. L. Daschbach, D. E. Gragson, G. L. Richmond Sep 1994

Sensitivity Of Second Harmonic Generation To Space Charge Effects At Si(111)/Electrolyte And Si(111)/Sio2/Electrolyte Interfaces, P. R. Fischer, J. L. Daschbach, D. E. Gragson, G. L. Richmond

Chemistry and Biochemistry

The potential dependence in the surface second harmonic response from hydrogen terminated n‐Si(111) and oxidized n‐Si(111) surfaces has been examined in aqueous NH4F and H2SO4 solutions. The relative phase of the nonlinear response as measured by rotational anisotropy experiments is found to be highly sensitive to the presence of the oxide and the field applied across the Si(111)/oxide/electrolyte interface. These observations are attributed to field effects within the space–charge region of the semiconductor which vary with the presence and thickness of the insulating oxide layer on the ...


Review Of Survival, Reproduction, And Behavior By J.R. Krebs And N.B. Davies, Marlene Zuk, Torgeir S. Johnsen, Gita R. Kolluru, Kurt A. Mckean, Bradd Schulke Sep 1994

Review Of Survival, Reproduction, And Behavior By J.R. Krebs And N.B. Davies, Marlene Zuk, Torgeir S. Johnsen, Gita R. Kolluru, Kurt A. Mckean, Bradd Schulke

Biological Sciences

No abstract provided.


Navel Orangeworm (Lepidoptera: Pyralidae) Development In Sunburned Walnuts, Mark D. Shelton, Donald W. Davis Aug 1994

Navel Orangeworm (Lepidoptera: Pyralidae) Development In Sunburned Walnuts, Mark D. Shelton, Donald W. Davis

Office of the Dean (CAFES) Scholarship

Navel orangeworrns, Amyelois transitella (Walker), completed development in sunburned walnuts late in the growing season, but moths did not emerge until after harvest. Sunburned walnuts were not attractive to ovipositing moths until considerable hull damage occurred. Only sunburned walnuts with undamaged kernels were suitable for larval development. Navel orangeworrn infestation levels up to 38% were recorded in sunburned walnut samples from the San Joaquin Valley, CA. Nut hull tissue damaged by sunburn was not selected over undamaged hull tissue for moth oviposition. Mean kernel temperatures of sunburned walnuts were higher than both undamaged walnuts and ambient air temperature. Premature hullsplit ...


Disparate Rates Of Molecular Evolution In Cospeciating Hosts And Parasites, M. S. Hafner, P. D. Sudman, F. X. Villablanca, T. A. Spradling, J. W. Demastes, S. A. Nadler Aug 1994

Disparate Rates Of Molecular Evolution In Cospeciating Hosts And Parasites, M. S. Hafner, P. D. Sudman, F. X. Villablanca, T. A. Spradling, J. W. Demastes, S. A. Nadler

Biological Sciences

DNA sequences for the gene encoding mitochondrial cytochrome oxidase I in a group of rodents (pocket gophers) and their ectoparasites (chewing lice) provide evidence for cospeciation and reveal different rates of molecular evolution in the hosts and their parasites. The overall rate of nucleotide substitution (both silent and replacement changes) is approximately three times higher in lice, and the rate of synonymous substitution (based on analysis of fourfold degenerate sites) is approximately an order of magnitude greater in lice. The difference in synonymous substitution rate between lice and gophers correlates with a difference of similar magnitude in generation times.


The Role Of Enzyme Activation State In Limiting Carbon Assimilation Under Variable Light Conditions, Gretchen F. Sassenrath-Cole, Robert W. Pearcy, Scott J. Steinmaus Aug 1994

The Role Of Enzyme Activation State In Limiting Carbon Assimilation Under Variable Light Conditions, Gretchen F. Sassenrath-Cole, Robert W. Pearcy, Scott J. Steinmaus

Biological Sciences

The mechanisms regulating transient photosynthesis by soybean (Glycine max) leaves were examined by comparing photosynthetic rates and carbon reduction cycle enzyme activities under flashing (saturating 1 s lightflecks separated by low photon flux density (PFD) periods of different durations) and continuous PFD. At the same mean PFD, the mean photosynthetic rates were reduced under flashing as compared to continuous light. However, as the duration of the low PFD period lengthened, the CO2 assimilation attributable to a lightfleck increased. This enhanced lightfleck CO2 assimilation was accounted for by a greater postillumination CO2 fixation occurring after the lightfleck. The ...


Process To Remove Cholesterol From Dairy Products, Thomas Richardson, Rafael Jiménez-Flores Jul 1994

Process To Remove Cholesterol From Dairy Products, Thomas Richardson, Rafael Jiménez-Flores

Dairy Science

The present invention relates to a process for the removal of cholesterol from a processed or unprocessed dairy product, which process comprises: (a) obtaining a processed or unprocessed dairy product containing cholesterol (b) contacting the dairy product at a temperature of between about 35° and 80° C. with an amount of saponin effective to bind up to about 90% of the cholesterol present in the dairy product; (c) contacting a temperature of between about 35° and 80° C the cholesterol: saponin with an effective amount of diatomaceous earth; (d) separating the insoluble cholesterol: saponin/diatomaceous earth by filtration or centrifugation ...


Living Mulches Suppress Aphids In Broccoli, Michael J. Costello, Miguel A. Altieri Jul 1994

Living Mulches Suppress Aphids In Broccoli, Michael J. Costello, Miguel A. Altieri

Horticulture and Crop Science

A living mulch combines an annual crop with a cover crop to provide pest control and soil protection. Results of a study in the Salinas Valley show cabbage aphid infestation can be lowered on broccoli grown in living mulches compared to clean cultivation, possible because light reflectance patterns are less attractive to incoming aphids. Early and intense mowing of the cover crop and adequate irrigation maintained broccoli yield in living mulches relative to clean cultivation. Lack of specialized equipment is the main limitation to the commercial application of living mulches at this time.


Azorhizobium Caulinodans Respires With At Least Four Terminal Oxidases, Christopher Kitts, Robert A. Ludwig Feb 1994

Azorhizobium Caulinodans Respires With At Least Four Terminal Oxidases, Christopher Kitts, Robert A. Ludwig

Biological Sciences

In culture, Azorhizobium caulinodans used at least four terminal oxidases, cytochrome aa3 (cytaa3), cytd, cyto, and a second a-type cytochrome, which together mediated general, respiratory electron (e-) transport to O2. To genetically dissect physiological roles for these various terminal oxidases, corresponding Azorhizobium apocytochrome genes were cloned, and three cytaa3 mutants, a cytd mutant, and a cytaa3, cytd double mutant were constructed by reverse genetics. These cytochrome oxidase mutants were tested for growth, oxidase activities, and N2 fixation properties both in culture and in symbiosis with the ...


Models For Predicting The Lower Limit Of The Canopy-Air Temperature Difference Of Two Cool Season Grasses, Dennis L. Martin, David J. Wehner, C. S. Throssell Jan 1994

Models For Predicting The Lower Limit Of The Canopy-Air Temperature Difference Of Two Cool Season Grasses, Dennis L. Martin, David J. Wehner, C. S. Throssell

Office of the Dean (CAFES) Scholarship

Estimation of the lower limit of the canopy-air temperature differential, (Tc–Ta)LL, is required for calculation of an empirically-based crop water stress, index. This research determined the complexity of model needed for accurate estimation of (Tc–Ta)LL for several field grown cultivars of Kentucky bluegrass (Poa pratensis L.) and for creeping bentgrass (Agrostis stolonifera L. var. palustris (Huds.) Farw.). Regression models using vapor pressure deficit of the air (VPD), net radiation load (Rn), and wind speed (WS) were developed for predicting (Tc–Ta)LL. The best one to three-variable regression models ...


Nutrient Uptake And Organic Acid Anion Metabolism In Lupins And Peas Supplied With Nitrate, S. P. Loss, A. D. Robson, G. S.P. Ritchie Jan 1994

Nutrient Uptake And Organic Acid Anion Metabolism In Lupins And Peas Supplied With Nitrate, S. P. Loss, A. D. Robson, G. S.P. Ritchie

Food Science and Nutrition

Unlike many plants reported in the literature, lupins do not excrete OH− in amounts equivalent to the net excess of inorganic anion uptake over inorganic cation uptake. To investigate the mechanisms involved in the maintenance of charge balance, nutrient uptake and organic anion accumulation of lupins and peas supplied with a range of NO3− concentrations, were compared. Lupins absorbed less NO3− than peas on a dry weight basis, which largely ACCOUNTED for the smaller excess of anion uptake over cation uptake in lupins than in peas at the same NO3− supply. When anion uptake exceeded cation uptake, peas excreted an ...


Spatial And Temporal Aspects Of Populations Revealed By Mitochondrial Dna, Francis X. Villablanca Jan 1994

Spatial And Temporal Aspects Of Populations Revealed By Mitochondrial Dna, Francis X. Villablanca

Biological Sciences

The evolutionary analysis of DNA sequences bridges phylogenetics and population genetics. Ancient DNA (aDNA) alJows the study of extinct genotypes, populations, and species, as well as dichronic comparisons of extant populations and species. Thus a DNA forges an empirical link between history and two inherently historical fields of research. Fortunately, the conceptual frameworks of phylogenetics and population genetics can easily be extended to encompass advances being made in the study of aDNA.


Icecolors '93: Biological Weighting Function For The Ultraviolet Inhibition Of Carbon Fixation In A Natural Antarctic Phytoplankton Community, Nicholas Boucher, Barbara B. Prezelin, T. Evens, R. Jovine, B. Kroon, Mark A. Moline, Oscar Schofield Jan 1994

Icecolors '93: Biological Weighting Function For The Ultraviolet Inhibition Of Carbon Fixation In A Natural Antarctic Phytoplankton Community, Nicholas Boucher, Barbara B. Prezelin, T. Evens, R. Jovine, B. Kroon, Mark A. Moline, Oscar Schofield

Biological Sciences

No abstract provided.


Palmer Lter: Impact Of A Large Diatom Bloom On Macronutrient Distribution In Arthur Harbor During Austral Summer 1991-1992, Mark A. Moline, Barbara B. Prezelin Jan 1994

Palmer Lter: Impact Of A Large Diatom Bloom On Macronutrient Distribution In Arthur Harbor During Austral Summer 1991-1992, Mark A. Moline, Barbara B. Prezelin

Biological Sciences

No abstract provided.


Palmer Lter: Photoadaptation In A Coastal Phytoplankton Bloom And Impact On The Radiation Utilization Efficiency For Carbon Fixation, Oscar Schofield, Barbara B. Prezelin, Mark A. Moline Jan 1994

Palmer Lter: Photoadaptation In A Coastal Phytoplankton Bloom And Impact On The Radiation Utilization Efficiency For Carbon Fixation, Oscar Schofield, Barbara B. Prezelin, Mark A. Moline

Biological Sciences

No abstract provided.


Impalement Of Marine Turtles (Reptilia, Chelonia: Cheloniidae And Dermochelyidae) By Billfishes (Osteichthyes, Perciformes: Istiophoridae And Xiphiidae), John G. Frazier, Harry L. Fierstine, Sallie C. Beavers, Federico Achaval, Hiroyuki Suganuma, Robert L. Pitman, Yuichiro Yamaguchi, Carlos Ma. Prigioni Jan 1994

Impalement Of Marine Turtles (Reptilia, Chelonia: Cheloniidae And Dermochelyidae) By Billfishes (Osteichthyes, Perciformes: Istiophoridae And Xiphiidae), John G. Frazier, Harry L. Fierstine, Sallie C. Beavers, Federico Achaval, Hiroyuki Suganuma, Robert L. Pitman, Yuichiro Yamaguchi, Carlos Ma. Prigioni

Biological Sciences

Billfishes have long been known to impale a great variety of objects, but there are only two brief, obscure records of marine turtles being speared. Details are presented on these two, as well as on two other confirmed records; data from two additional unconfirmed records are also presented. In total, three species of marine turtles are known to have been impaled by three species of billfishes; a fourth species of fish and a fourth species turtle are listed in an unconfirmed case. Records come from the eastern and western Pacific as well as the eastern Atlantic. Of the four confirmed ...


Role Of Dissolution And Precipitation Of Minerals In Controlling Soluble Aluminum In Acidic Soils, G. S. P. Ritchie Jan 1994

Role Of Dissolution And Precipitation Of Minerals In Controlling Soluble Aluminum In Acidic Soils, G. S. P. Ritchie

Food Science and Nutrition

No abstract provided.


Changes In The Forms Of Cadmium With Time In Some Western Australian Soils, S. S. Mann, G. S.P. Ritchie Jan 1994

Changes In The Forms Of Cadmium With Time In Some Western Australian Soils, S. S. Mann, G. S.P. Ritchie

Food Science and Nutrition

Changes in the forms of Cd with time could affect its uptake by plants and hence potential toxicity to animals and humans. The effect of time on the forms of native and added Cd was studied in four West Australian soils which differed in their clay, hydrous oxide and organic matter content. Sequential extraction of soluble (KCl), exchangeable (BaCl2), bound to organic matter (NaOCl), bound to oxides/clays (ammonium oxalate) and residual (concentrated acids) forms of Cd was carried out at different time intervals after the addition of Cd.
The Cd that was added to the soils transformed with ...


Amelioration Of Subsurface Acidity In Sandy Soils In Low Rainfall Regions. I. Responses Of Wheat And Lupins To Surface-Applied Gypsum And Lime, C. D. A. Mclay, G. S.P. Ritchie, W. M. Porter Jan 1994

Amelioration Of Subsurface Acidity In Sandy Soils In Low Rainfall Regions. I. Responses Of Wheat And Lupins To Surface-Applied Gypsum And Lime, C. D. A. Mclay, G. S.P. Ritchie, W. M. Porter

Food Science and Nutrition

Amelioration of subsoil acidity using gypsum (CaSO4·2H2O) or lime (CaCO3) was studied on sandy textured soils with low water holding capacity in a low rainfall environment. Field trials were established in 1989 at two sites on yellow sandplain soils to investigate whether different rates, sources and combinations of gypsum and lime application could be used to increase wheat and lupin yields. Gypsum increased wheat yields by up to 45% in the first two growing seasons whereas lime increased wheat yields by up to only 15% in the second season. The highest yields were generally recorded ...


Amelioration Of Subsurface Acidity In Sandy Soils In Low Rainfall Regions. Ii. Changes To Soil Solution Composition Following The Surface Application Of Gypsum And Lime, C. D. A. Mclay, G. S.P. Ritchie, W. M. Porter, A. Cruse Jan 1994

Amelioration Of Subsurface Acidity In Sandy Soils In Low Rainfall Regions. Ii. Changes To Soil Solution Composition Following The Surface Application Of Gypsum And Lime, C. D. A. Mclay, G. S.P. Ritchie, W. M. Porter, A. Cruse

Food Science and Nutrition

Two field trials were sampled to investigate the changes to soil solution chemical properties of a yellow sand plain soil with an acidic subsoil following the application of gypsum and lime to the soil surface in 1989. The soils were sandy textured and located in a region of low annual rainfall (300-350 mm). Soil was sampled annually to a depth of 1 m and changes in soil solution composition were estimated by extraction of the soil with 0.005 M KCl.
Gypsum leaching caused calcium (Ca), sulfate (SO4) and the ionic strength to increase substantially in both topsoil and ...


Phosphorus Leaching In Soils Amended With Piggery Effluent Or Lime Residues From Effluent Treatment, D. M. Weaver, G. S.P. Ritchie Jan 1994

Phosphorus Leaching In Soils Amended With Piggery Effluent Or Lime Residues From Effluent Treatment, D. M. Weaver, G. S.P. Ritchie

Food Science and Nutrition

Phosphorus (P) in wastes from piggeries may contribute to the eutrophication of waterways if not disposed of appropriately. Phosphorus leaching, from three soils with different P sorption characteristics (two with low P retention and one with moderate P retention) when treated with piggery effluent (with or without struvite), was investigated using batch and leaching experiments. The leaching of P retained in soil from the application of struvite effluent was determined. In addition, P leaching from lime residues (resulting from the treatment of piggery effluent with lime to remove P) was determined in comparison to superphosphate when applied to the same ...


Phosphorus Removal From Piggery Effluents Of Varying Quality Using Lime And Physico-Chemical Treatment Methods., D. M. Weaver, G. S. P. Ritchie Jan 1994

Phosphorus Removal From Piggery Effluents Of Varying Quality Using Lime And Physico-Chemical Treatment Methods., D. M. Weaver, G. S. P. Ritchie

Food Science and Nutrition

The choice of management practices for the treatment of piggery effluent prior to its disposal to waterways or land is governed by the desire to simultaneously minimise the cost of treatment whilst minimising pollution of the environment. Laboratory experiments were conducted to compare the removal of total and total filterable phosphorus (P) (μm) from ortho-phosphate solutions or piggery effluent by hydrated lime or lime kiln dust alone, or from recycled piggery effluent by lime and physico-chemical treatment methods. In addition, the ability of lime to remove P from recycled piggery effluent at an intensive piggery was assessed.

Most P ...