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1992

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The Advocate (Winter 1992), Lewis & Clark Law School Jan 1992

The Advocate (Winter 1992), Lewis & Clark Law School

The Advocate

No abstract provided.


Black Box Spring 1992, Eileen Landis-Groom, Pete Daniel, Katie Tucker, Kevin Weirich, Chris Goodrich, Jason O'Connor, Michelle Peevler, Debbie Lewis, Monte Byrom, Jonathon Wichern, Peg Rhodes, Stephen Wise, Michael Wason, Bhawna Giare, Kat, Emal Meop, Ajo, Mark Francis, S.T.E., Flight Commander Bigglesworth, Pamela Herring, Frank Bennett, Wild Al, Bob Battema, K.C. Alexander, The Zen Warrior, Mark, Tajmon Newborn, Miklos, Paul Conti, Kevin C. Donovan, Matt Sauer, Jake Olsen Jan 1992

Black Box Spring 1992, Eileen Landis-Groom, Pete Daniel, Katie Tucker, Kevin Weirich, Chris Goodrich, Jason O'Connor, Michelle Peevler, Debbie Lewis, Monte Byrom, Jonathon Wichern, Peg Rhodes, Stephen Wise, Michael Wason, Bhawna Giare, Kat, Emal Meop, Ajo, Mark Francis, S.T.E., Flight Commander Bigglesworth, Pamela Herring, Frank Bennett, Wild Al, Bob Battema, K.C. Alexander, The Zen Warrior, Mark, Tajmon Newborn, Miklos, Paul Conti, Kevin C. Donovan, Matt Sauer, Jake Olsen

Black Box

The Black Box is a student run service organization that publishes poems, short stories, lyrics, photographs, and works of art created by students and faculty members of Embry-Riddle's Prescott Campus.


Optimal Response To Periodic Shortage: Engineering/Economic Analysis For A Large Urban Water District, Anthony Fisher, David Fullerton, Nile Hatch, Peter Reinelt Jan 1992

Optimal Response To Periodic Shortage: Engineering/Economic Analysis For A Large Urban Water District, Anthony Fisher, David Fullerton, Nile Hatch, Peter Reinelt

Faculty Publications

The problem addressed by this study is how a large urban water district can best respond to a drought or the prospect of a drought. Specifically, what is the least cost combination of alternatives to meet periodic shortages? A solution to this problem may involve structural approaches (such as developing new local storage capacity), a mix of structural and nonstructural (such as conjunctive use combined with water exchanges or sales), or purely nonstructural approaches (such as changes in water pricing). The application is to the East Bay Municipal Utility District (EBMUD), which includes portions of Alameda and Contra Costa counties …


Plea-Bargaining As A Social Contract, Robert E. Scott, William J. Stuntz Jan 1992

Plea-Bargaining As A Social Contract, Robert E. Scott, William J. Stuntz

Faculty Scholarship

Most criminal prosecutions are settled without a trial. The parties to these settlements trade various risks and entitlements: the defendant relinquishes the right to go to trial (along with any chance of acquittal), while the prosecutor gives up the entitlement to seek the highest sentence or pursue the most serious charges possible. The resulting bargains differ predictably from what would have happened had the same cases been taken to trial. Defendants who bargain for a plea serve lower sentences than those who do not. On the other hand, everyone who pleads guilty is, by definition, convicted, while a substantial minority …


Studies On Tsetse Midgut Factors That Induce Differentiation Of Bloodstream Trypanosoma Brucei Brucei In Vitro, M. O. Imbuga, E. O. Osir, V. L. Labongo, N. Darji, L. H. Otieno Jan 1992

Studies On Tsetse Midgut Factors That Induce Differentiation Of Bloodstream Trypanosoma Brucei Brucei In Vitro, M. O. Imbuga, E. O. Osir, V. L. Labongo, N. Darji, L. H. Otieno

All Peer-Reviewed Publications

An in vitro system for studying the transformation of bloodstream forms of Trypanosoma brucei brucei into procylic (midgut) forms is described. In this system, transformation of the parasites was stimulated by Glossina morsitans morsitans midgut homogenates at 27° C but not at 4° C. The transformation-stimulating capacity was irreversibly destroyed by heating the midgut homogenates at 60° C for 1 h. A correlation was established between the transformation activity of the midgut homogenates and trypsin activity. The protease inhibitors (soybean trypsin inhibitor and N-p-tosyl-l-lysine-chloromethyl-ketone) inhibited trypsin activity and completely blocked the transformation of the parasites. Furthermore, the midgut homogenates could …


Influence Of Exposure Period And Management Methods On The Effectiveness Of Chickens As Predators Of Ticks Infesting Cattle, S. M. Hassan, O. O. Dipeolu, D. M. Munyinyi Jan 1992

Influence Of Exposure Period And Management Methods On The Effectiveness Of Chickens As Predators Of Ticks Infesting Cattle, S. M. Hassan, O. O. Dipeolu, D. M. Munyinyi

All Peer-Reviewed Publications

Experiments undertaken on Rusinga Island, Kenya, indicated that Rhipicephalus appendiculatus (Neumann) was the predominant tick consumed on tick-infested cattle by chickens, followed by Amblyomma variegatum (Fabricius), Boophilus decoloratus (Koch) and Rhipicephalus evertsi evertsi (Neumann). The number of ticks consumed by chickens released with cattle in a 3 h release period was not significantly different from ticks consumed in a 4 h release period. In a free management system, chickens 1-3 months of age consumed more ticks than older ones; in a confined management system however, chickens 4-6 months of age consumed more ticks than younger birds. Although the numbers of …


Influence Of D(+)-Glucosamine On Infection Rates And Parasite Loads In Tsetse Flies (Glossina Spp.) Infected With Trypanosoma Brucei, Steve Mihok, Leonard H. Otieno, Nafisa Darji, David Munyinyi Jan 1992

Influence Of D(+)-Glucosamine On Infection Rates And Parasite Loads In Tsetse Flies (Glossina Spp.) Infected With Trypanosoma Brucei, Steve Mihok, Leonard H. Otieno, Nafisa Darji, David Munyinyi

All Peer-Reviewed Publications

Teneral Glossina morsitans centralis, G. m. morsitans and G. pallidipes were infected with three different clones of Trypanosoma brucei in blood containing d(+)-glucosamine, an inhibitor of tsetse midgut lectin. On average, 5 days of d(+)-glucosamine treatment tripled infection rates, without affecting the proportion of infections that matured. Total infection rates were equal in males and females, but twice as many infections matured in males. Counts of parasites in the guts and salivary glands of 277 flies revealed order of magnitude differences among flies, with females consistently having 2-3-times as many parasites as males. Parasite numbers varied in a sex-specific manner …


Studies On Naturally Acquired Immunity To African Ticks. Ii. Observations On Cattle Exposed To Rhipicephalus Appendiculatus Under Varying Periods Of Repeated Infestations, Olusegun O. Dipeolu, Abdul O. Mongi, Suliman Essuman, Abimboia O. Amoo, Joseph N. Ndungu Jan 1992

Studies On Naturally Acquired Immunity To African Ticks. Ii. Observations On Cattle Exposed To Rhipicephalus Appendiculatus Under Varying Periods Of Repeated Infestations, Olusegun O. Dipeolu, Abdul O. Mongi, Suliman Essuman, Abimboia O. Amoo, Joseph N. Ndungu

All Peer-Reviewed Publications

Groups of Friesian cattle were infested repetedly with Rhipicephalus appendiculatus at weekly intervals (eight infestations) and at intervals of 3 weeks (seven infestations) and 6 weeks (seven infestations). The engorgement weight of adults, nymphs and larvae decreased significantly initially, from the second infestation, but rose significantly at later infestations. This rise was more dramatic with larval instars than with any other. A new method for quantifying the resistance status of animals was introduced; this method showed that the resistance acquired by cattle during 6-weekly reinfestations was more stable than that acquired by cattle during weekly and 3-weekly reinfestations. The criteria …


Laboratory And Field Observations On Anti-Tick Properties Of The Plant Gynandropsis Gynandra (L.) Brig, M. M. Malonza, O. O. Dipeolu, A. O. Amoo, S. M. Hassan Jan 1992

Laboratory And Field Observations On Anti-Tick Properties Of The Plant Gynandropsis Gynandra (L.) Brig, M. M. Malonza, O. O. Dipeolu, A. O. Amoo, S. M. Hassan

All Peer-Reviewed Publications

A shrubby plant, abundant in east Kenya, Gynandropsis gynandra (L.) Brig., was shown to exhibit repellent and acaricidal properties to larvae, nymphs and adult Rhipicephalus appendiculatus and Amblyomma variegatum ticks. All stages of ticks avoided the leaves of the plant and a high percentage of the ticks which were continuously exposed to its leaves died; surviving ticks were weak and inactive but regained activity when exposed to fresh air. The effectiveness of the plant's leaves as a repellent and acaricide was most pronounced on nymphs and least pronounced on adults. Field investigations indicated that ticks were not found up to …


Influence Of Maize Row Spacing On Infestation And Damage Of Intercropped Beans By The Bean Aphid (Aphis Fabae Scop.). Ii. Reduction In Bean Yields, M. W. Ogenga-Latigo, C. W. Baliddawa, J. K.O. Ampofo Jan 1992

Influence Of Maize Row Spacing On Infestation And Damage Of Intercropped Beans By The Bean Aphid (Aphis Fabae Scop.). Ii. Reduction In Bean Yields, M. W. Ogenga-Latigo, C. W. Baliddawa, J. K.O. Ampofo

All Peer-Reviewed Publications

Field studies were conducted to assess the effects of intercropping common beans (Phaseolus vulgaris L.) with maize (Zea mays L.), at two growth stages and four row spacings (0.5, 1.0, 1.5 and 2.0 m), on Aphis fabae infestation of beans and on the magnitudes of bean yield losses due to aphid attack and to competition by maize. The first maize planting (Old maize) was carried out 3 weeks earlier than beans, while the second planting (Young maize) was done simultaneously with beans. Significantly (P < 0.05) fewer plants were infested by A. fabae when beans were intercropped with older or densely planted maize. Aphid colonies on beans were also smaller, and there was reduced aphid damage to beans in the intercrops. However, whereas bean yield loss from aphid attack was less than 3.5% in all intercrop situations, yield loss from competition by maize was very high, being up to 98% when beans were intercropped with early-planted maize at 0.5-m row spacing. Yields of intercropped maize planted at row spacings of 0.5, 1.5 and 2.0 m were also depressed. The results show that both maize growth and row spacing could be exploited for the control of A. fabae on intercropped beans. However, adequate consideration must be given to the negative effects of maize planting density and growth on yields of both crops. © 1992.


The Morphology Of Convex Polygons, Stephan Olariu Jan 1992

The Morphology Of Convex Polygons, Stephan Olariu

Computer Science Faculty Publications

A simple polygon P is said to be unimodal if for every vertex of P, the Euclidian distance function to the other vertices of P is unimodal. The study of unimodal polygons has emerged as a fruitful area of computational and discrete geometry. We study unimodality properties of a number of special convex polygons from the morphological point of view. In particular, we establish a hierarchy among three classes of convex polygons in terms of their unimodality properties.


On Sources In Comparability Graphs, With Applications, Stephan Olariu Jan 1992

On Sources In Comparability Graphs, With Applications, Stephan Olariu

Computer Science Faculty Publications

We characterize sources in comparability graphs and show that our result provides a unifying look at two recent results about interval graphs.


A Tree Representation For P4-Sparse Graphs, B. Jamison, Stephan Olariu Jan 1992

A Tree Representation For P4-Sparse Graphs, B. Jamison, Stephan Olariu

Computer Science Faculty Publications

A graph G is P4-sparse if no set of five vertices in G induces more than one chordless path of length three. P4-sparse graphs generalize both the class of cographs and the class of P4-reducible graphs. We give several characterizations for P4-sparse graphs and show that they can be constructed from single-vertex graphs by a finite sequence of operations. Our characterization implies that the P4-sparse graphs admit a tree representation unique up to isomorphism. Furthermore, this tree representation can be obtained in polynomial time.


A Charming Class Of Perfectly Orderable Graphs, Chinh T. Hoang, Frederic Maffray, Stephan Olariu, Myriam Preissmann Jan 1992

A Charming Class Of Perfectly Orderable Graphs, Chinh T. Hoang, Frederic Maffray, Stephan Olariu, Myriam Preissmann

Computer Science Faculty Publications

We investigate the following conjecture of Vašek Chvátal: any weakly triangulated graph containing no induced path on five vertices is perfectly orderable. In the process we define a new polynomially recognizable class of perfectly orderable graphs called charming. We show that every weakly triangulated graph not containing as an induced subgraph a path on five vertices or the complement of a path on six vertices is charming.


Making The Secular Sacred: An Analysis Of Linguistic Devices Used To Give Religious Perspective To Ordinary Events., Wayne Porter Gregory Jan 1992

Making The Secular Sacred: An Analysis Of Linguistic Devices Used To Give Religious Perspective To Ordinary Events., Wayne Porter Gregory

LSU Historical Dissertations and Theses

It has been suggested that human beings do not possess social reality so much as they actively and cooperatively construct it by means of language in interaction with others. The manipulation of symbols, the creation of inferences, the posturing of one's personal identity all work together to enable participants (both speakers and hearers) in a given speech event to create social reality and reaffirm and maintain their social relationships. In religious speech communities, like the one investigated in this study, participants seek to create a different kind of social reality--one that encompasses all of the individual and corporate experiences of …


A Conjoint Analysis Of Wetland-Based Recreation: A Case Study Of Louisiana Waterfowl Hunting., Christopher Ec Gan Jan 1992

A Conjoint Analysis Of Wetland-Based Recreation: A Case Study Of Louisiana Waterfowl Hunting., Christopher Ec Gan

LSU Historical Dissertations and Theses

Conjoint analysis is a recent evolution in mathematical psychology that has been employed extensively in the marketing environment. The technique is concerned with measuring the joint effect of two or more independent variables on the ordering of a dependent variable. Conjoint analysis relates an individual's preferences to a set of prespecified attributes. The objective of conjoint analysis is to decomposed a set of responses to factorially designed stimuli in which the utility of each stimuli attribute can be inferred from the respondents' evaluations of the stimuli. In addition, conjoint analysis and its economic foundations are developed in the context of …


Soot Suppressing Mechanisms Of Iron In Premixed Hydrocarbon Flames., David Worthington Hahn Jan 1992

Soot Suppressing Mechanisms Of Iron In Premixed Hydrocarbon Flames., David Worthington Hahn

LSU Historical Dissertations and Theses

In-situ light scattering measurements are combined with chemical analysis of sampled soot particles to elucidate the mechanisms through which iron addition affects soot formation and growth processes in fuel-rich, premixed propane and oxygen flames. Soot particle optical inhomogeneity resulting from the addition of iron is accounted for in the light scattering analysis using an effective refractive index model. The influence of iron addition on soot particle diameters, number densities, volume fractions, surface areas, and specific growth rates is investigated. In addition, X-ray photoelectron spectroscopy was used to determine the chemical state of iron species throughout the flame. The analysis revealed …


Distinctions Between Reefs And Bioherms Based On Studies Of Fossil Algae: Mizzia, Permian Capitan Reef Complex (Guadalupe Mountains, Texas And New Mexico) And Eugonophyllum, Pennsylvanian Holder Formation (Sacramento Mountains, New Mexico)., Brenda Kirkland George Jan 1992

Distinctions Between Reefs And Bioherms Based On Studies Of Fossil Algae: Mizzia, Permian Capitan Reef Complex (Guadalupe Mountains, Texas And New Mexico) And Eugonophyllum, Pennsylvanian Holder Formation (Sacramento Mountains, New Mexico)., Brenda Kirkland George

LSU Historical Dissertations and Theses

The udoteacean alga Eugonophyllum is well-preserved in the Virgilian Holder Formation, Sacramento Mountains. Original aragonite occurs as a felt-like mesh of needles in algal thalli, mollusc fragments, sponge walls, botryoidal, and isopachous marine cements. In the basal, heavily calcified portion of Eugonophyllum the interior of the thallus is composed of aragonitic felt punctuated by 20 $\mu$m diameter, parallel siphons. In the distal, less calcified portion of the thallus, irregularly arranged siphons are larger. This study substantiates suggested similarities between Pennsylvanian/Permian phylloid algal mounds and Holocene Halimeda mounds. The Permian dasyclad Mizzia is important for paleoecological study in the Guadalupe Mountains, …


Incorporating Reservoir Characteristics For Automatic History Matching., Keith J. Halford Jan 1992

Incorporating Reservoir Characteristics For Automatic History Matching., Keith J. Halford

LSU Historical Dissertations and Theses

Automatic history matching is refined in this work by expanding the objective function and incorporating reservoir characteristics in the process of parameter selection. Iso-value contours are used to incorporate reservoir characteristics within history-matching parameters. These improvements are implemented in an automatic history-matching algorithm, OPTIM, that is coupled with BOAST II. Case histories of both hypothetical and real reservoirs demonstrated the effectiveness of incorporating reservoir characteristics in automatic history-matching parameters.


Development Of Various Quantitative And Analytical Methods For The Analysis Of The Dynamics Of Fish Populations: An Application To The Spotted Seatrout Population In Coastal Louisiana., Thomas Earl Helser Jan 1992

Development Of Various Quantitative And Analytical Methods For The Analysis Of The Dynamics Of Fish Populations: An Application To The Spotted Seatrout Population In Coastal Louisiana., Thomas Earl Helser

LSU Historical Dissertations and Theses

Presented in this dissertation are analytical and quantitative methods developed for an experimental gillnet sampling program for the analysis of the dynamics of fish populations, illustrated here on Louisiana's spotted seatrout population. Chapter 1 presents a new method of estimating gillnet selectivity using a system of simultaneous equations and a non-linear iterative maximum likelihood approach. The model solution is a set of parameter estimates which mathematically describe the response surface of capture probabilities for fish of size-class j in mesh size i. As an extension to the nonlinear maximum likelihood gillnet selectivity model, Chapter 2 presents a second approach using …


Effects Of Heat And Iron Fractions On Lipid Oxidation In Meat., Dongmei Han Jan 1992

Effects Of Heat And Iron Fractions On Lipid Oxidation In Meat., Dongmei Han

LSU Historical Dissertations and Theses

Size exclusion (SE) and hydrophobic interaction (HIC) high performance liquid chromatography (HPLC) methods were developed for determining hemoglobin, myoglobin, and total pigments in beef and chicken. Hemoglobin and myoglobin in beef, but not in chicken, were separated by HIC with minimum detectable levels of 0.187 and 0.085 $\mu$g/$\mu$l, respectively. Determination of total pigment by SE-HPLC (minimum detection of 0.001 $\mu$g/$\mu$l) was more sensitive than with spectrophotometric assay. The effects of heat at 55$\sp\circ$C, 70$\sp\circ$C, 85$\sp\circ$C, and 100$\sp\circ$C on the distribution of iron in six fractions (water-soluble, water-insoluble, diffusate, hematin, total heme, and ferritin) in beef and chicken muscles were determined. …


Consumer Evaluation Of Product-Related Injuries: The Development And Empirical Testing Of A Behavioral Model Of The Product Liability Process., Bryce Mitchell Griffin Jan 1992

Consumer Evaluation Of Product-Related Injuries: The Development And Empirical Testing Of A Behavioral Model Of The Product Liability Process., Bryce Mitchell Griffin

LSU Historical Dissertations and Theses

This study strives to provide a better understanding of consumer evaluation of product liability cases. A model of consumer perceptions of the liability process, based predominantly on attribution theory, is developed and tested. The research first develops a general attributional model of the liability process, identifies relevant managerially-controllable dimensions of liability cases, and then tests consumer reaction to these factors utilizing experimental scenarios. The influence of several consumer-juror individual difference variables on the evaluation of liability cases is examined. In addition, potential mediators of the product liability process, including assessment of responsibility and affective evaluation of the plaintiff and defendant, …


The Keepers And The Kept: The First Hundred Years Of The Tennessee State Prison System, 1830-1930. (Volumes I And Ii)., Larry D. Gossett Jan 1992

The Keepers And The Kept: The First Hundred Years Of The Tennessee State Prison System, 1830-1930. (Volumes I And Ii)., Larry D. Gossett

LSU Historical Dissertations and Theses

Tennessee built its first state penitentiary in Nashville in 1830 on Sixteenth and Church Streets on land that is now a downtown parking lot. Revisions in the criminal code made many offenses punishable by imprisonment instead of corporal or capital punishment, and the convict population grew steadily. Continuing concern was expressed by the General Assembly that the penitentiary be self-supporting, and much effort was expended at all levels of government to accomplish that end. This study covers the history of approximately the first one hundred years of the Tennessee State Prison System. It begins with an overview of the criminal …


Improvement Of The Data Analysis Algorithm By Applying The Decision Tree Method., Won Chan Jung Jan 1992

Improvement Of The Data Analysis Algorithm By Applying The Decision Tree Method., Won Chan Jung

LSU Historical Dissertations and Theses

Data analysis (reconstructability analysis) is an area used on a data set which has several variables and a function value to find the most important factor that causes the function values to fall within a desired range. Normal data analysis algorithm (1) finds the most important factor in O (2$\sp{n})$ time. This dissertation introduces a newly developed system of algorithms called the Data Analyzing Tree (DAT) which is designed to either reduce the time complexity or produce more accurate results. DAT-1 uses O $(n\sp2)$ time to produce the same results as the normal data analysis method, and DAT-2 produces the …


Chemical And Immunological Properties Of Polysaccharide Extracted From Vibrio Parahaemolyticus., Mina Jassemzadeh Izadjoo Jan 1992

Chemical And Immunological Properties Of Polysaccharide Extracted From Vibrio Parahaemolyticus., Mina Jassemzadeh Izadjoo

LSU Historical Dissertations and Theses

The capsular polysaccharide (CPS) of Vibrio parahaemolyticus was extracted from agar grown cells and purified by ethanol precipitation, hi-speed centrifugation and chromatography on Sepharose CL-4B and Detoxi columns. The CPS was found to be acidic when chromatographed on DEAE cellulose. The three constituting sugars were determined by gas-liquid chromatography to be glucose, galactose and fucose. The molecular weight of CPS is one million or greater and in its pure form appeared to be non-immunogenic for rabbits. A monoclonal antibody (Mab) reactive by ELISA to CPS was generated. The Mab agglutinated whole cell suspensions in the slide test. Latex beads armed …


Genetic And Systematic Study Of Viviparus Georgianus (Lea), A Freshwater Snail Species Complex., Masaya Katoh Jan 1992

Genetic And Systematic Study Of Viviparus Georgianus (Lea), A Freshwater Snail Species Complex., Masaya Katoh

LSU Historical Dissertations and Theses

Genetic and morphological variation were studied in a brooding (ovoviviparous) and morphologically variable freshwater snail (Viviparus georgianus (Lea)) in the southeastern United States. Eleven populations were clustered into three genetically isolated, allopatric species characterized by 7 to 15 diagnostic loci out of the 38 loci examined. These allopatric species were an eastern species (in eastern and southern Florida), a western species (in the Florida panhandle), and a central species in the Ochlockonee River. Nei's standard genetic distances between species were large (0.23-0.52) compared to within-species distances (0.00-0.06). Moreover, genetic distances between the Ochlockonee River species and other species were larger …


Three Essays On International Linkages Of The Korean Economy., Jai-Ki Lee Jan 1992

Three Essays On International Linkages Of The Korean Economy., Jai-Ki Lee

LSU Historical Dissertations and Theses

This dissertation consists of three essays. The first essay investigates whether the long run version of purchasing power parity (PPP) holds between Korea and its two major trading partners--the U.S. and Japan. The PPP relationship is examined using cointegration tests, which are proper to see the departures from the long run equilibrium. The second essay examines the empirical relationship between real exchange rates and interest rate differentials in the Korean-U.S. as well as the Korean-Japanese economies. This relationship is also examined using cointegration tests. The third essay examines how foreign economic shocks affect the Korean economy and analyzes the channels …


Control Of Phytoplankton Production In A Shallow, Turbid Estuary., Christopher J. Madden Jan 1992

Control Of Phytoplankton Production In A Shallow, Turbid Estuary., Christopher J. Madden

LSU Historical Dissertations and Theses

Water column primary production and chlorophyll were sampled between 1986-1991 in Fourleague Bay, LA, a shallow (1.5 m), river-dominated estuary that is extremely turbid (K$\sb{\rm D}$ = 4.44 m$\sp{-1}$). A high speed system for continuous flow-through sampling, Dataflow$\sp\copyright$, was developed to measure physicochemical variables and in vivo chlorophyll fluorescence at high temporal (1 s) and spatial (5 m) resolution from a small boat. Phytoplankton net primary production (NPP) was measured using an incubator which rotated bottles to prevent settling of the contents. NPP was found to be artificially increased by 10-83% at high light levels in non-rotated bottles when cells …


Development Of A Portable And Selective Volatile Organic Compound Analyzer Based On An Enhanced Microchip Gas Chromatograph., Aaron Meleki Mainga Jan 1992

Development Of A Portable And Selective Volatile Organic Compound Analyzer Based On An Enhanced Microchip Gas Chromatograph., Aaron Meleki Mainga

LSU Historical Dissertations and Theses

Although the use of portable gas chromatographs is a well established technique, it is still experiencing rapid growth. For continued growth and acceptance, however, it must be a viable alternative over the use of traditional gas chromatographs, in terms of its applicability for identification of important compounds, and its routine use for the analysis of volatile organic compounds (voc) in ambient air. The biggest limitation to the use of portable gas chromatographs is their lack of sensitivity to low concentrations of voc's. Most portable gas chromatographs at present have a detection limit of about 1 ppmv, while the concentration of …


Diagnostic Techniques For Detection Of Permethrin-Resistant Soybean Loopers, Pseudoplusia Includens (Walker), Determination Of The Impact Of Insecticide Treatments On Age-Specific Mortality And Feeding Activity, And Estimation Of Field Control., Jeffrey Scott Mink Jan 1992

Diagnostic Techniques For Detection Of Permethrin-Resistant Soybean Loopers, Pseudoplusia Includens (Walker), Determination Of The Impact Of Insecticide Treatments On Age-Specific Mortality And Feeding Activity, And Estimation Of Field Control., Jeffrey Scott Mink

LSU Historical Dissertations and Theses

A glass vial bioassay was developed to detect permethrin resistance in soybean looper, Pseudoplusia includens (Walker), larvae. Third, fourth, fifth, and sixth instar soybean loopers from laboratory (susceptible) and field strains were exposed to several concentrations of permethrin in 20 ml glass vials. LC$\sb{50}$'s for third, fourth, and fifth instars from each field strain were not significantly different. A discriminating concentration of 0.5 $\mu$g permethrin per vial was identified for detection of permethrin resistance in soybean looper field populations. Field strains from cotton-soybean agroecosystems exhibited higher levels of resistance than strains from soybean-corn agroecosystems. The reliability of the vial bioassay …