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Full-Text Articles in Life Sciences

A Review Of The Nearctic Species Of The Thrips-Attacking Genus Ceranisus Walker (Hymenoptera: Eulophidae), S. V. Triapitsyn, David H. Headrick Dec 1995

A Review Of The Nearctic Species Of The Thrips-Attacking Genus Ceranisus Walker (Hymenoptera: Eulophidae), S. V. Triapitsyn, David H. Headrick

Horticulture and Crop Science

The thrips-attacking Eulophidae (subfamily Entedoninae) known from the Nearctic region are reviewed. One new species, Ceranisus loomansi, is described. Four other species of Ceranisus are redescribed and illustrated based mainly on a study of their type specimens as well as on additional material from Arizona, California, Hawaii, Mississippi and Japan. Lectotypes are designated for Ceranisus americensis (Girault), C. nubilipennis (Williams) and C. russelli (Crawford). A key to eight species belonging to four entedonine thrips-attacking genera is given, and host associations are indicated for those species.


Pseudomonas Aeruginosa Strain Ma01 Aerobically Metabolizes The Aminodinitrotoluenes Produced By 2,4,6-Trinitrotoluene Nitro Group Reduction, Mark A. Alvarez, Christopher Kitts, James L. Botsford, Pat J. Unkefer Nov 1995

Pseudomonas Aeruginosa Strain Ma01 Aerobically Metabolizes The Aminodinitrotoluenes Produced By 2,4,6-Trinitrotoluene Nitro Group Reduction, Mark A. Alvarez, Christopher Kitts, James L. Botsford, Pat J. Unkefer

Biological Sciences

Many microbes reduce the nitro substituents of 2,4,6-trinitrotoluene (TNT), producing aminodinitrotoluenes (ADNTs). These compounds are recalcitrant to further breakdown and are acutely toxic. In a search for organisms capable of metabolizing ADNTs, a bacterial strain was isolated for the ability to use 2-aminobenzoate (anthranilate) as sole C-source. This isolate, Pseudomonas aeruginosa MAO1, metabolized TNT by first reducing one nitro group to form either 2-amino-4,6-dinitrotoluene (2ADNT) or 4 -amino-2,6-dinitrotoluene(4ADNT). However, strain MA01 was distinct from other TNT-reducing organisms in that it transformed these compounds into highly polar metabolites through an 02-dependent process. Strain MAOl was able ...


Tunable Picosecond Infrared Laser System Based On Parametric Amplification In Ktp With A Ti:Sapphire Amplifier, D. E. Gragson, D. S. Alavi, G. L. Richmond Oct 1995

Tunable Picosecond Infrared Laser System Based On Parametric Amplification In Ktp With A Ti:Sapphire Amplifier, D. E. Gragson, D. S. Alavi, G. L. Richmond

Chemistry and Biochemistry

A picosecond laser system that will generate high-power tunable IR pulses with bandwidths suitable for spectroscopic applications is discussed. The system is based on white-light continuum generation in ethylene glycol and optical parametric amplification in potassium titanyl phosphate. The nonlinear-optical processes are driven by a regeneratively amplified Ti:sapphire laser that produces 1.7-ps pulses at a repetition rate of 1 kHz. Energies as high as 40 and 12 µJ have been achieved over the signal (1.02–1.16-µm) and idler (2.6–3.7-µm) tuning ranges, respectively. The IR beam temporal and spatial characteristics are also presented.


Three-Phase Intersection Points In Monolayers, John P. Hagen, Harden M. Mcconnell Sep 1995

Three-Phase Intersection Points In Monolayers, John P. Hagen, Harden M. Mcconnell

Chemistry and Biochemistry

Some phospholipid/dihydrocholesterol Langmuir monolayers form coexisting liquid phases. Gas domains form at the interface between the phospholipid-rich and dihydrocholesterol-rich liquid phases when these monolayers undergo expansion to low surface pressure. Analysis of the domain shapes thus formed yields the relative line tensions of the gas/phospholipid, gas/dihydrocholesterol, and phospholipid/dihydrocholesterol phase interfaces.


On The Dangers Of Interpopulational Transfers Of Monarch Butterflies, Lincoln P. Brower, Linda S. Fink, Andrew Van Zandt Brower, Kingston L. H. Leong, Karen Oberhauser, Sonia Altizer, Orley Taylor, Daniel Vickerman, William H. Calvert, Tonya Van Hook, Alfonso Alonso-Mejia, Stephen B. Malcolm, Denis F. Owen, Myron P. Zalucki Sep 1995

On The Dangers Of Interpopulational Transfers Of Monarch Butterflies, Lincoln P. Brower, Linda S. Fink, Andrew Van Zandt Brower, Kingston L. H. Leong, Karen Oberhauser, Sonia Altizer, Orley Taylor, Daniel Vickerman, William H. Calvert, Tonya Van Hook, Alfonso Alonso-Mejia, Stephen B. Malcolm, Denis F. Owen, Myron P. Zalucki

Biological Sciences

No abstract provided.


Spider (Araneae) Species Composition And Seasonal Abundance In San Joaquin Valley Grape Vineyards, Michael J. Costello, Kent M. Daane Aug 1995

Spider (Araneae) Species Composition And Seasonal Abundance In San Joaquin Valley Grape Vineyards, Michael J. Costello, Kent M. Daane

Horticulture and Crop Science

As part of an investigation to estimate the effect of resident spider populations on Erythroneura variabilis Beamer, spider species composition, relative abundance, and seasonal occurrence were determined. Spiders were sampled monthly during the 1992 and 1993 growing seasons; their numbers were pooled and analyzed for species diversity using the Renkonen index of similarity and cluster analysis. Twenty-seven species of spiders were recorded, representing 14 families. The most common species were Cheiracanthium inclusum (Hentz), Trachelas pacificus (Chamberlin and Ivie), Theridion dilutum Levi, Theridion melanurum Hahn, Oxyopes scalaris Hentz, Oxyopes salticus Hentz, Hololena nedra Chamberlin and Ivie, and Metaphidippus vitis (Cockerell). Three ...


Spectral Reflectance From A Broccoli Crop With Vegetation Or Soilias Background: Influence On Immigration By Brevicoryne Brassicae And Myzus Persicae, Michael J. Costello May 1995

Spectral Reflectance From A Broccoli Crop With Vegetation Or Soilias Background: Influence On Immigration By Brevicoryne Brassicae And Myzus Persicae, Michael J. Costello

Horticulture and Crop Science

Light reflectance in five wavebands of the spectrum was measured from broccoli (Brassicae oleracea var.botrytis [L].) interplanted with leguminous cover crops (cover crop background) or broccoli grown as monoculture (bare soil background), and fertilized with compost or synthetic fertilizer. Alate Brevicoryne brassicae (L.) and Myzus persicae (Sulzer) (Homoptera: Aphididae) were monitored in yellow pan water traps and on broccoli leaves. Reflectance intensity was higher with a background of bare soil at all wavebands except blue (400–455 nm) in the early-season. Intensity decreased as broccoli canopy cover increased at all wavebands except blue and green (515–550 nm), declining-most ...


A Computer-Based Tool For Introducing Turfgrass Species, T. W. Fermanian, David J. Wehner Apr 1995

A Computer-Based Tool For Introducing Turfgrass Species, T. W. Fermanian, David J. Wehner

Office of the Dean (CAFES) Scholarship

An essential component of an introductory turfgrass management course is the description of how turfgrass species are adapted to different cultural systems and environments. The objectives of this project were to develop an interactive program to introduce the characteristics of turfgrass species and their optimum environments and to evaluate the students' gain in understanding turf species characteristics through this approach. A self-contained application, Turf Species, was constructed using the SuperCard development tool. Turf Species consists of three sections including a self-paced tour of the species, a what if establishment section, and randomly composed reinforcement quizzes with automatic grading. Turf Species ...


Abundance, Growth Rate And Parasitism Of Brevicoryne Brassicae And Myzus Persicae (Homoptera: Aphididae) On Broccoli Grown In Living Mulches, Michael J. Costello, Miguel A. Altieri Feb 1995

Abundance, Growth Rate And Parasitism Of Brevicoryne Brassicae And Myzus Persicae (Homoptera: Aphididae) On Broccoli Grown In Living Mulches, Michael J. Costello, Miguel A. Altieri

Horticulture and Crop Science

In 1990 and 1991, populations of the cabbage aphid, Brevicoryne brassicae, and the green peach aphid, Myzus persicae, were monitored on broccoli interplanted with three leguminous cover crops (the living mulches) and compared with broccoli without cover crop (clean cultivation). The cover crops used were white clover (Trifolium repens L.), strawberry clover (Trifolium fragiferum L.) and a mixture of birdsfoot trefoil (Lotus corniculatus L.) and red clover (Trifolium praetense L.). Fertilizer was applied as compost or synthetic fertilizer crossed with cropping system regime. Brevicoryne brassicae can reach pest status in Brassica cropping systems, whereas M. persicae is generally innocuous. Both ...


Reply To Nylin, Wickman & Wiklund Regarding Sex Ratios Of California Overwintering Monarch Butterflies, Dennis F. Frey, Kingston L. H. Leong Feb 1995

Reply To Nylin, Wickman & Wiklund Regarding Sex Ratios Of California Overwintering Monarch Butterflies, Dennis F. Frey, Kingston L. H. Leong

Biological Sciences

No abstract provided.


Vacuum-Packaged Precooked Pork From Hogs Fed Supplemental Vitamin E: Chemical, Shelf-Life And Sensory Properties, J. E. Cannon, J. B. Morgan, G. R. Schmidt, R. J. Delmore, J. N. Sofos, G. C. Smith, S. N. Williams Jan 1995

Vacuum-Packaged Precooked Pork From Hogs Fed Supplemental Vitamin E: Chemical, Shelf-Life And Sensory Properties, J. E. Cannon, J. B. Morgan, G. R. Schmidt, R. J. Delmore, J. N. Sofos, G. C. Smith, S. N. Williams

Animal Science

Precooked longissimus chops and semimembranosus/adductor roasts from pigs (n = 30) given no supplemental vitamin E (CON) or supplemented with 100 mg vitamin E/kg diet (VITE) were evaluated for lipid oxidation, microbial growth, sensory characteristics, cooking/storage losses and reheating losses. Chops and roasts were vacuum packaged, precooked to 60°C and stored at 2°C for 0, 7, 14, 28, or 56 days. Lipid oxidation was lower in VITE chops and roasts than in CON chops and roasts. Off-flavor intensity scores were more acceptable and storage/ cooking losses were lower for VITE roasts than for CON roasts. Supplementation ...


Life History And Description Of Immature Stages Of Euaresta Stigmatica (Diptera: Tephritidae) On Ambrosia Spp. (Asteraceae) In Southern California, David H. Headrick, Richard D. Goeden, Jeffrey A. Teerink Jan 1995

Life History And Description Of Immature Stages Of Euaresta Stigmatica (Diptera: Tephritidae) On Ambrosia Spp. (Asteraceae) In Southern California, David H. Headrick, Richard D. Goeden, Jeffrey A. Teerink

Horticulture and Crop Science

Euaresta stigmatica Coquillett is bivoltine and nearly monophagous on four native ragweeds, Ambrosia spp. (Asteraceae), in the southwestern United States. In southern California, larvae of the spring (F1) generation develop singly in and feed on one or both ovules of young fruiting involucres of Ambrosia ilicifolia (Gray) Payne, with a small proportion infesting the staminate involucres. Adults emerge after ≈1 mo, with their reproductive organs immature. The F2 generation develops in the involucres of fall-blooming Ambrosia acanthicarpa Hooker. The egg is described and illustrated for the first time for any species of Euaresta. First, second, and third instars ...


Behaviors Of Female Eretmocerus Sp. Nr. Californicus (Hymenoptera: Aphelinidae) Attacking Bemisia Argentifolii (Homoptera: Aleyrodidae) On Sweet Potato, David H. Headrick, Thomas S. Bellows, Jr., Thomas M. Perring Jan 1995

Behaviors Of Female Eretmocerus Sp. Nr. Californicus (Hymenoptera: Aphelinidae) Attacking Bemisia Argentifolii (Homoptera: Aleyrodidae) On Sweet Potato, David H. Headrick, Thomas S. Bellows, Jr., Thomas M. Perring

Horticulture and Crop Science

Behaviors of Eretmocerus sp. nr. californicus Howard females on Bemisia argentifolii Bellows & Perring infesting sweet potato, Ipomoea batatas (L.) Lain, were described and quantified. Walking speeds of up to 1.3 mm/s were calculated for females searching for host whitefly nymphs on sweet potato leaves. Females encountered all host stages during searching with approximately the same relative frequency as their relative abundance (average of 17.03% of hosts available were encountered). Females also arrested and antennated all of the host stages with the same relative frequency as their encounter rate (62.8%). Females showed a clear and significant preference for probing second instars over all other stages. Of the hosts probed, females chose all stages for oviposition with the same relative frequency. Successful exsertion of the ovipositor under a host nymph occurred after initial probes 12 times and after repeated probing attempts 15 times. Oviposition occurred under 13.5% of the hosts assessed by antennation; however, 20 of the 27 (74%) nymphs under which the ovipositor was exserted received an egg. Females spent 41% of the total time in searching, host assessment, probing, and oviposition: the remainder of the time (59%) was spent host feeding, grooming, and resting.


Split-Root Nutrition Of Sweetpotato In Hydroponic Systems, M. A. Sherif, P. A. Loretan, A. A. Trotman, D. G. Mortley, J. Y. Lu, Lauren C. Garner Jan 1995

Split-Root Nutrition Of Sweetpotato In Hydroponic Systems, M. A. Sherif, P. A. Loretan, A. A. Trotman, D. G. Mortley, J. Y. Lu, Lauren C. Garner

Horticulture and Crop Science

Nutrient film technique (NFT) and deep water culture (DWC) hydroponic systems were used in a split-root study of the effect of four treatments on sweetpotato yield, the translocation of assimilates, and microbial population count. ‘TU-155’ cuttings (15 cm) were prerooted for 30 days in sand using deionized water and a modified half-Hoagland (MHH) solution. After 30 days, the plants were removed, and the roots of each were cleaned and split evenly between two sides of a channel (each 15 cm deep by 15 cm wide by 1.2 m long), four plants per channel. Replicated treatments were: MHH/MHH; MHH ...


Induction Of Larval Settlement By Kcl In Three Species Of Bugula (Bryozoa), Dean E. Wendt, Robert M. Woollacott Jan 1995

Induction Of Larval Settlement By Kcl In Three Species Of Bugula (Bryozoa), Dean E. Wendt, Robert M. Woollacott

Biological Sciences

Elevation of the K+ concentration in seawater (added as KCl) induces larval settlement and metamorphosis in Bugula simplex, B. stolonifera, and B. turrita. All three of these bryozoan species have similar bell-shaped dose-response curves: 5 mM excess K+ is sufficient to increase settlement and metamorphosis significantly over seawater controls in all the species and optimal responses to excess K concentrations occur ations at 10-25 mM, 5-10 mM, and 10-15 mM for B. simplex, B. stolonifera, and B. turrita, respectively. Percent settlement in all three species is decreased at levels greater than 25 mniM excess KCl. Similar bell-shaped curves have been ...


Palmer Lter: Photoacclimation In A Coastal Phytoplankton Bloom, Oscar Schofield, Mark A. Moline, Barbara B. Prezelin Jan 1995

Palmer Lter: Photoacclimation In A Coastal Phytoplankton Bloom, Oscar Schofield, Mark A. Moline, Barbara B. Prezelin

Biological Sciences

No abstract provided.


Statistical Analyses Of Environmental Predictors For Phytoplankton Photosynthetic Parameters And Productivity In An Antarctic Time Series Database, Mark A. Moline, Barbara B. Prezelin, Oscar Schofield Jan 1995

Statistical Analyses Of Environmental Predictors For Phytoplankton Photosynthetic Parameters And Productivity In An Antarctic Time Series Database, Mark A. Moline, Barbara B. Prezelin, Oscar Schofield

Biological Sciences

No abstract provided.


Soluble Aluminium In Acidic Soils: Principles And Practicalities, G. S.P. Ritchie Jan 1995

Soluble Aluminium In Acidic Soils: Principles And Practicalities, G. S.P. Ritchie

Food Science and Nutrition

Our ability to predict toxic quantities of aluminium (Al) in acidic soils is limited by our understanding of the interactions between different solid forms of Al in solution and our lack of knowledge of which form control soluble Al. This review briefly considers each type of solid form of Al, particularly from a kinetic point of view and discusses models that have been developed to predict release of Al from individual forms. More comprehensive models (i.e. more than one source or sink of Al) are then discussed as well as the interactions between different solid sources of Al.


Forms Of Cadmium In Sandy Soils After Amendment With Soils Of Higher Fixing Capacity, S. S. Mann, G. S. P. Ritchie Jan 1995

Forms Of Cadmium In Sandy Soils After Amendment With Soils Of Higher Fixing Capacity, S. S. Mann, G. S. P. Ritchie

Food Science and Nutrition

Most of the Cd applied through phosphatic fertilizers in sandy soils tends to stay in mobile forms (soluble or exchangeable) and hence the risk of it leaching to underground water or its uptake by plants is higher. A sequential extraction procedure was used to assess the efficacy of amending materials (soils containing inorganic or organic adsorption components) on the re-distribution of forms of Cd in a sandy soil. Amendment of the sandy soil with each of the three soils (yellow earth, lateritic podzolic and peaty sand) was generally effective in altering the more mobile or available forms of Cd to ...


Effect Of Gypsum Application Rate And Leaching Regime On Wheat Growth In A Highly Acidic Subsoil, C. D.A. Mclay, G. S. P. Ritchie Jan 1995

Effect Of Gypsum Application Rate And Leaching Regime On Wheat Growth In A Highly Acidic Subsoil, C. D.A. Mclay, G. S. P. Ritchie

Food Science and Nutrition

A glasshouse experiment "was conducted to investigate gypsum application and leaching on the amelioration of" an aluminium (Al) toxic subsoil for wheat growth. Treatments included different rates of gypsum application and amount of leaching prior to wheat being grown. Wheat shoot growth increased when gypsum was applied in both the presence and absence of leaching, but growth was higher with leaching. Gypsum application led to a decrease in toxic Al as a result of a higher ionic strength and activity of AlSO4+ion pairs in the soil solution, and increased Al leached from the soil. Root growth may not ...


Abnormal Properties Of Milk From Transgenic Mice Expressing Bovine Β-Casein Under Control Of The Bovine Α-Lactalbumin 5' Flanking Region, Rafael Jiménez-Flores, Gregory T. Bleck, Robert D. Bremel Jan 1995

Abnormal Properties Of Milk From Transgenic Mice Expressing Bovine Β-Casein Under Control Of The Bovine Α-Lactalbumin 5' Flanking Region, Rafael Jiménez-Flores, Gregory T. Bleck, Robert D. Bremel

Dairy Science

Transgenic mice produced in this investigation contained the proximal promoter elements, the genomic coding sequence and the 3' flanking region of bovine β-casein and the 5' regulatory elements of bovine α-lactalbumin. Specifically, the gene construct included the TATAA box, CAAT box and polyadenylation signal of bovine β-casein in addition to the 5' regulatory elements of the bovine α-lactalbumin gene. Four lines of transgenic mice were generated; they expressed bovine β-casein in their milk at concentrations of up to 10 mg mL-1. The milk from the transgenic mice tended to be very viscous and a proportion of these mice stopped ...


Influence Of Genetic Variants Of Κ-Casein And Β-Lactoglobulin In Milk On Proteolysis In Cheddar Cheese, G. I. Imafidon, N. Y. Farkye, Phillip S. Tong, V. R. Harwalkar Jan 1995

Influence Of Genetic Variants Of Κ-Casein And Β-Lactoglobulin In Milk On Proteolysis In Cheddar Cheese, G. I. Imafidon, N. Y. Farkye, Phillip S. Tong, V. R. Harwalkar

Dairy Science

No abstract provided.