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Selected Works

Selected Works

1992

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Articles 1 - 12 of 12

Full-Text Articles in Life Sciences

A Review Of The Factors Influencing The Growth Of The Northern Quahog, Mercenaria Mercenaria (Linnaeus, 1758), Michael A. Rice, Jan A. Pechenik Nov 1992

A Review Of The Factors Influencing The Growth Of The Northern Quahog, Mercenaria Mercenaria (Linnaeus, 1758), Michael A. Rice, Jan A. Pechenik

Michael A Rice

Factors affecting the growth of larval, juvenile, and adult northern quahogs, Mercenaria mercenaria, are reviewed. Larval growth is affected by temperature, salinity, current speed, dissolved oxygen concentration, and the amount of suspended sediments in the water, along with such nutritional factors as food quantity and quality. Growth of post-set juvenile and adult quahogs is similarly affected by the same physical and nutritional factors. Recent work suggests that there is a strong genetic contribution to quahog growth rate and that selective breeding programs may be useful for producing rapid growth strains. A growing body of evidence suggests that larval growth rates …


The Cpce And Cpcf Genes Of Synechococcus Sp. Pcc 7002. Construction And Phenotypic Characterization Of Interposon Mutants, J Zhou, G E. Gasparich, V L. Stirewalt, R De Lorimier, D A. Bryant Aug 1992

The Cpce And Cpcf Genes Of Synechococcus Sp. Pcc 7002. Construction And Phenotypic Characterization Of Interposon Mutants, J Zhou, G E. Gasparich, V L. Stirewalt, R De Lorimier, D A. Bryant

Gail Gasparich

The 3' region of the cpc operon of Synechococcus sp. PCC 7002 has been sequenced, transcriptionally characterized, and analyzed by interposon mutagenesis. The cpc operon contains six genes, 5' cpcB-cpcA-cpcC-cpcD-cpcE-cpcF 3', and gives rise to at least eight (more likely ten) discrete mRNA transcripts. The steady-state levels of transcripts for the cpcE and cpcF genes are very low and are estimated to represent only about 1-2% of the total transcripts arising from the cpc locus. The cpcE gene predicts a protein of 268 amino acid residues, whereas the cpcF gene predicts a protein of 205 amino acid residues. The deduced …


Die Konsequenzen Eines Lebens Im Druckbehälter. Biotheoretische Implikationen Der Organisation Pflanzlicher Organismen [The Consequences Of Living In A Pressure Pot. Biotheoretical Implications Of The Organismic Architecture Of Plants], Winfried Peters, Hubert Felle Jun 1992

Die Konsequenzen Eines Lebens Im Druckbehälter. Biotheoretische Implikationen Der Organisation Pflanzlicher Organismen [The Consequences Of Living In A Pressure Pot. Biotheoretical Implications Of The Organismic Architecture Of Plants], Winfried Peters, Hubert Felle

Winfried S. Peters

Die Betrachtung der sich aus der zellulären Osmo- und Druckregulation ergebenden konstruktiven Zwänge erlaubt es, invariante Eigenschaften makroskopischer Pflanzen abzuleiten. Sessilität wird als grundsätzlich unumgänglich erkannt; Autotrophie als zwangsläufige Ernährungsform kann nur durch Parasitismus oder Beteiligung an Symbiosen umgangen werden. Hieraus ergibt sich die Antwort auf die Frage nach dem “Unterschied” zwischen Tieren und Pflanzen: die Bildung clonarer Kolonien (Metapopulationen) kann bei sessilen Organismen besonders plausibel begründet werden, zumal, wenn diese autotroph leben. Sessilität stellt bei Tieren eine Option, bei makroskopischen Pflanzen aber eine Notwendigkeit dar. Das Vorherrschen des Konstruktionstyps “Metapopulation” bei Pflanzen ist damit vorgezeichnet; dies ist letztlich eine …


Trends In Overwintering Egg Populations Of A Pine Sawfly, Neodiprion Autumnalis, On Ponderosa Pine Sampled In January And December 1991 Near Ft. Meade In South Dakota, Judith E. Pasek, Willis C. Schaupp Jr Apr 1992

Trends In Overwintering Egg Populations Of A Pine Sawfly, Neodiprion Autumnalis, On Ponderosa Pine Sampled In January And December 1991 Near Ft. Meade In South Dakota, Judith E. Pasek, Willis C. Schaupp Jr

Judith E Pasek

In 1990 and 1991, a number of outbreaks of the pine sawfly, Neodiprion autumnalis, were reported in western South Dakota and eastern Wyoming. Near Ft. Meade in South Dakota, defoliation in 1990 was heavy at the center of the infestation and decreased to light defoliation at a distance of 1 mile from the center. Defoliation at the same location in 1991 appeared to range from heavy to moderate.

Three sites near Ft. Meade that were sampled in January 1991 were resurveyed in December 1991 to assess changes in overwintering egg populations and degree of defoliation and to determine the potential …


Canid Elicitation Of Blood-Squirting In A Horned Lizard (Phrynosoma Cornutum), George Middendorf, Wade Sherbrooke Mar 1992

Canid Elicitation Of Blood-Squirting In A Horned Lizard (Phrynosoma Cornutum), George Middendorf, Wade Sherbrooke

George Middendorf

No abstract provided.


Populations Of Douglas-Fir Beetle In Green Trees Three Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Judith Pasek, Willis Schaupp Feb 1992

Populations Of Douglas-Fir Beetle In Green Trees Three Years After The Clover Mist Fire On The Clarks Fork Ranger District, Shoshone National Forest, Wyoming, Judith Pasek, Willis Schaupp

Judith E Pasek

Brood densities of Douglas-fir beetle (DFB), Dendroctonus pseudotsugae Hopkins, in green trees adjoining areas burned by the 1988 Clover Mist Fire varied by site, but averaged 8 per 36 sq. in. for bark samples at all sites examined during November 1991. Brood densities were much reduced from 1990 levels, but were similar to densities found in blackened trees in fall 1989. The reduction from 1990 levels was attributed to heavy winter mortality of brood caused by prolonged extreme cold temperatures. Most brood in fall 1991 samples was present in the callow adult stage, similar to 1989 samples, and in contrast …


Status And Trends Of Mountain Pine Beetle Populations In The Bear Mountain And White House Gulch Areas On The Harney Ranger District, Black Hills National Forest, South Dakota, Judith E. Pasek, Willis C. Schaupp Jr Feb 1992

Status And Trends Of Mountain Pine Beetle Populations In The Bear Mountain And White House Gulch Areas On The Harney Ranger District, Black Hills National Forest, South Dakota, Judith E. Pasek, Willis C. Schaupp Jr

Judith E Pasek

Increasing and epidemic populations of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae) were detected and evaluated in the southcentral Black Hills. Mortality of ponderosa pine, Pinus ponderosa Dougl. ex Laws., in the area increased each year since 1988 and was six times greater in 1991 than in 1989. Survey results indicate an average of 29 trees killed per acre by this bark beetle from 1989 through 1991 in the Bearhouse project area. Infestation is especially concentrated in the Bear Mountain Basin area, where between 27 and 103 trees per acre have been killed, and a large beetle population …


A Capacity Theory Of Comprehension: Individual Differences In Working Memory, Marcel Just, Patricia Carpenter Dec 1991

A Capacity Theory Of Comprehension: Individual Differences In Working Memory, Marcel Just, Patricia Carpenter

Marcel Adam Just

No abstract provided.


Bivalve Aquaculture In Warm Tropical And Subtropical Waters With Reference To Sanitary Water Quality, Monitoring And Post-Harvest Disinfection, Michael A. Rice Dec 1991

Bivalve Aquaculture In Warm Tropical And Subtropical Waters With Reference To Sanitary Water Quality, Monitoring And Post-Harvest Disinfection, Michael A. Rice

Michael A Rice

The warm water and high primary productivity of tropical estuaries allows for rapid growth and production of bivalves, but sanitary quality of molluscan shellfish poses one of the single largest impediments to development of international markets. The regulations of the US Food and Drug Administration (FDA) are outlined as representative of regulations governing international trade of fresh and frozen molluscan shellfish. The status of shellfisheries and molluscan aquaculture in several tropical and subtropical nations is presented. A number of developing nations, including Mexico, Peru and the Philippines, have established export markets for fresh scallop adductor meats because they are not …


The Effects Of Copper, Cadmium And Zinc On Particle Filtration And Uptake Of Glycine In The Pacific Oyster Crassostrea Gigas, Wenyu Lin, Michael A. Rice, Paul K. Chien Dec 1991

The Effects Of Copper, Cadmium And Zinc On Particle Filtration And Uptake Of Glycine In The Pacific Oyster Crassostrea Gigas, Wenyu Lin, Michael A. Rice, Paul K. Chien

Michael A Rice

1. The filtration rate (volume of water completely cleared of collodial carbon per unit time) by control oysters is 36.60 ml/g hr ± 7.68 (sd).2. Filtration rates decrease with increasing concentrations of Cd2+ and Zn2+.3. In 8–16 mg/l Cu2+, filtration rates are significantly higher than the control, but in Cu2+ concentrations above 32 mg/l, filtration rates are lower than controls.4. Influx of 14C-glycine is characterized by Michaelis-Menten kinetics with Jmax and Kt values of 1.85 ± 0.097 μmol/g hr and 33.7 ± 4.6 μM respectively.5. The uptake rate of glycine from 1 μM solution is 37.79 μmol/g hr.6. In order …


Rearing Systems For Screwworm Mass Production, David B. Taylor Dec 1991

Rearing Systems For Screwworm Mass Production, David B. Taylor

David B. Taylor

No abstract provided.


Incorporating Pest Information Into Forest Planning: Personal Experience From The Black Hills, Judith E. Pasek Dec 1991

Incorporating Pest Information Into Forest Planning: Personal Experience From The Black Hills, Judith E. Pasek

Judith E Pasek

Paper presented at the 40th Annual Western International Forest Disease Work Conference.