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Articles 2041 - 2070 of 2108

Full-Text Articles in Pharmacology, Toxicology and Environmental Health

Evaluation Of Allergic Hypersensitivity To 2,4-D, Malathion, And Captafol In Mice, Janette R. Cushman May 1982

Evaluation Of Allergic Hypersensitivity To 2,4-D, Malathion, And Captafol In Mice, Janette R. Cushman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

2,4-D-specific IgE antibodies were detected in serum of BALB/c mice using the rat passive cutaneous anaphylaxis (PCA) test following the second intraperitoneal immunization with 1, 10, or 100 ug of 2,4-D0keyhole limpet hemocyanin (KLH) conjugate administered with aluminum hydroxide adjuvant. The groups that received 1 ug of 2,4-D conjugate had the highest antibody titers (geometric mean of 60). A paper radioallergosorbent test (PRAST) was developed for determination of 2,4-D-specific IgE. The PRAST was equally as sensitive as and showed a positive correlation with the PCA assay.

The anhydride of the diacid metabolite of malathion (MMA) coupled to KLH elicited MMA-specific …


Blood Levels Of 5-Bromo-2'-Deoxyuridine In Intraperitoneal Infusion For Determination Of Sister Chromatid Exchange Induction Using Hplc, Angelo Turturro, Narendra P. Singh, Johnny Bazare Jr., Ronald W. Hart Jan 1982

Blood Levels Of 5-Bromo-2'-Deoxyuridine In Intraperitoneal Infusion For Determination Of Sister Chromatid Exchange Induction Using Hplc, Angelo Turturro, Narendra P. Singh, Johnny Bazare Jr., Ronald W. Hart

Journal of the Arkansas Academy of Science

A new technique was developed to measure the amount of 5-bromo-2 '-deoxyurdine (BrdUrd), a thymidine analogue, rapidly and conveniently in blood, and it was applied to measure the concentration of BrdUrd during the initiation of a paradigm for the labeling of DNA to measure the induction of sister chromatid exchanges (SCE) by genotoxic agents. Radio labelled BrdUrd was used and blood was drawn from the abdominal aorta in pregnant Sprague-Dawley derived D rats. Using the hplc, the BrdUrd peak was easily identifiable and separable from its metabolites. The BrdUrd level in the blood stabilized in 30 minutes, and a level …


Inhibitors Affecting Bacterial Action In Reaerated Activated Sludge, Alice M. Dunn Jan 1982

Inhibitors Affecting Bacterial Action In Reaerated Activated Sludge, Alice M. Dunn

Masters Theses

Inhibition of reaerated activated sludge was assessed using reduction of dissolved oxygen uptake by the microbial population as a criterion. Oxygen uptake is essential to biodegradation of the organic components in the activated sludge process; therefore, a decrease in dissolved oxygen uptake is an indication of reduced efficiency in wastewater treatment.

The irihibitors tested were cadmium, copper, lead, mercury, silver, 2,4-Dichlorophenoxyacetic acid (2,4-D), Terbacil and Zectran. The IIC50, determined by extrapolation of plotted data, for each inhibitor in mg/l was Hg (20), Cu (50), Ag (43), Cd (115), Pb (550), and 2,4-D (430). The IIC50 was determined …


Alterations In Rat Brain Norepinephrine And Dopamine Levels And Synthesis Rates In Response To Five Neurotoxic Chemicals: Acrylamide, 2,5-Hexanedione, Tri-O-Tolyl Phosphate, Leptophos, And Methyl Mercuric Chloride, Charles N. Aldous May 1981

Alterations In Rat Brain Norepinephrine And Dopamine Levels And Synthesis Rates In Response To Five Neurotoxic Chemicals: Acrylamide, 2,5-Hexanedione, Tri-O-Tolyl Phosphate, Leptophos, And Methyl Mercuric Chloride, Charles N. Aldous

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Acrylamide, 2,5-hexanedione, Tri-o-tolyl phosphate and leptophos belong to three fundamentally different chemical classes but all four chemicals cause central-peripheral distal axonopathy. Some of these compounds have been shown to alter brain steady state levels of neurotransmitters or to inhibit the activities of adenosine triphosphatases which are involved in the uptake and storage of biogenic amines. Tests were performed to determine alterations in steady state levels of rat brain norepinephrine and dopamine in response to doses of the above chemicals and of the central nervous system toxin, methyl mercuric chloride sufficient to cause ataxia. Catecholamine synthesis rate constant estimations were performed. …


Influence Of Lipophilicity On The Accumulation And Distribution Of Halogenated Phenols And A Pyridinol As Metabolites Of Pesticides In The Rat, Assed A. Attumi May 1981

Influence Of Lipophilicity On The Accumulation And Distribution Of Halogenated Phenols And A Pyridinol As Metabolites Of Pesticides In The Rat, Assed A. Attumi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Exposure to halogenated phenols and pyridinols is of increasing concern because of their wide use and distribution. This research was initiated to determine the distribution, accumulation, and depletion of a group of halogenated phenols and a pyridinol in selected tissues of male weanling rats at different time intervals following a single oral dose of 0.33 or 1.66 m moles per kg body weight. The halogenated phenols and pyridinol were distributed differently in every tissue sampled following their administration, even though the amount administered was the same in each case. The concentrations in tissue were found in the order: 2,4,5-trichlorophenol > 4-bromo-2,5-dichlorophenol …


Accumulation Of Formaldehyde And Its Relation To Postmortem Aging Of Non-Gadoid Fish Species, Mohamad A. Al-Kanhal May 1980

Accumulation Of Formaldehyde And Its Relation To Postmortem Aging Of Non-Gadoid Fish Species, Mohamad A. Al-Kanhal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three non-gadoid fish species, trout (Cynoscion regalis), English sole (Paraophyrys vetulus) and Pacific red snapper (Scomber japonicus) have been tested for the recovery of trimethylamine oxide (TMAO), trimethylamine (TMA), dimethylamine (DMA), and formaldehyde (FA) during postmortem storage at 4°C and -5°C. TMAO, TMA, and DMA content was determined by measuring them as the salt derivative of picric acid. FA was determined by using the 3-Methyl-2-Benzothiazolinone hydrazone test.

In muscle tissue of red snapper and English sole, it was clear that initially TMAO decreased during storage at 4°C, while the amounts of TMA, DMA, and …


Inhibition Of Synaptosomal Biogenic Amine Transport By A Diverse Group Of Neurotoxic Chemicals, William M. Bracken May 1980

Inhibition Of Synaptosomal Biogenic Amine Transport By A Diverse Group Of Neurotoxic Chemicals, William M. Bracken

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synaptosomal membrane functions were monitored, after in vitro exposure to select environmental pollutants, in synaptosomal preparations originating from rat cerebral cortices. The uptake of NE and 5HT into the synaptosomes was monitored as was the K+-dependent phosphate activity of the membrane. CH3HgCl, Hg(NO3)2, CdCl2, diisopropylfluorophosphate (DFP), paraoxon, acrylamide and Kepone were the test chemicals whose effects were studied.

CH3HgCl, Hg(NO3)2 and Kepone had the greatest inhibitory effects on NE and 5HT uptake. The concentrations producing 50 percent inhibition (IC50) were 1.4 x 10 …


Pesticide Exposure Studies: Direct And Indirect Detection Of Absorption Of 2,4-D And Pronamide Herbicides In The Guinea Pig And Occupationally Exposed Workers, Ibrahim A.R. Al-Jabery May 1980

Pesticide Exposure Studies: Direct And Indirect Detection Of Absorption Of 2,4-D And Pronamide Herbicides In The Guinea Pig And Occupationally Exposed Workers, Ibrahim A.R. Al-Jabery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A simple high pressure liquid chromatography procedure was used to determine 2,4-D and pronamide exposure in spraymen and their dermal absorption and excretion in guinea pigs.

Results of dermal application of these herbicides to guinea pigs demonstrated a strong correlation between the applied dermal dose and the urinary residue excretion over the dosage range tested. As the dosage was increased, the urinary excretion of residues was also increased. However, the excretion of 2,4-D amine mixture following dermal treatment of guinea pigs was prolonged as compared to that of pronamide.

Residue levels of these compounds were also determined to estimate skin …


A Computer Simulation Study Of Blood Cholinesterase Inhibition In Parathion Treated Rats, Scott Christopher Hennes May 1980

A Computer Simulation Study Of Blood Cholinesterase Inhibition In Parathion Treated Rats, Scott Christopher Hennes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A computer simulation model of blood cholinesterase inhibition in rats resulting from a single oral or dermal dose of parathion was developed and tested. The model consists of a set of non-linear differential equations describing the absorption, distribution and metabolism of parathion and the kinetics of inhibition and reactivation of erythrocyte and plasma cholinesterase. The equations are numerically integrated to produce the time-course of each of the cholinesterase activities of the blood. The model was tested for validity by a comparison of the activities predicted by the model to values determined experimentally in male rats. The model successfully simulated plasma …


Leptophos Metabolism In The Rat: An In Vivo Study Of Oxidative Versus Conjugative Modes Of Metabolism, David Richard Hampson May 1980

Leptophos Metabolism In The Rat: An In Vivo Study Of Oxidative Versus Conjugative Modes Of Metabolism, David Richard Hampson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this research were to examine the metabolism in vivo of the pesticide leptophos in the rat under normal conditions and during inhibition of the mixed-function oxidases and during depletion of glutathione. Glutathione is a cofactor in the conjugation reactions of the glutathione-S-transferases. Both the mixed-function oxidase system and the glutathione-S-transferases have been shown to be important in the biotransformation of other organophosphate pesticides.

Urinary metabolites of leptophos were extracted, derivatized and subsequently analyzed by gas-liquid chromatography. The methods used to analyze for alkyl phosphonates were subject to several shortcomings and modifications of the original procedure were necessary. …


The Effects Of Tri-O-Tolyl Phosphate (Totp) On The Immune System Of Mice, Craig R. Brinkerhoff May 1980

The Effects Of Tri-O-Tolyl Phosphate (Totp) On The Immune System Of Mice, Craig R. Brinkerhoff

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

TOTP is a prevalent industrial and environmental contaminant which has been shown to be a neurotoxic agent. This study was undertaken to investigate the effects of this compound on the immune system. Several techniques were employed to test the humoral as well as cellular effects. Male Swiss Webster mice were administered by gastric gavage with three doses of TOTP (5, 50, and 500 mg/kg) and one dose TMTP (50 mg/kg) in corn oil once a week for 13 weeks. Control animals were given corn oil alone.

Lymphocyte transformation was determined on cultures of splenic cells obtained from animals sacrificed at …


Effects Of Organic Compounds On Amphibian Reproduction, Wesley J. Birge, Jeffrey A. Black, Robert A. Kuehne Jan 1980

Effects Of Organic Compounds On Amphibian Reproduction, Wesley J. Birge, Jeffrey A. Black, Robert A. Kuehne

KWRRI Research Reports

Aquatic toxicity tests were conducted with atrazine, carbon tetrachloride, chloroform, methylene chloride, trisodium nitrilotriacetic acid (NTA), and phenol. Each compound was administered to developmental stages of three to five amphibian species. Exposure was initiated at fertilization and maintained through 4 days posthatching. Test responses included lethality and teratogenesis. Different amphibian species exhibited varying degrees of tolerance to the selected compounds. Greatest tolerance usually was observed for the more broadly adapted semi-aquatic and terrestrial species (e.g., Bufo americanus, Bufo fowleri). The more sensitive amphibians usually included those species which normally are restricted to aquatic or moist habitats (e.g., Rana …


Metals In Apple Cider Produced And Marketed In Connecticut, Dennis W. Hill, Thomas R. Kelley, Gale R. Morrow, Sylvia W. Matiuck Dec 1979

Metals In Apple Cider Produced And Marketed In Connecticut, Dennis W. Hill, Thomas R. Kelley, Gale R. Morrow, Sylvia W. Matiuck

Storrs Agricultural Experiment Station

No abstract provided.


Bulletin 3967 - Cyanogenetic Plants Of Western Australia, T E H Aplin Jun 1979

Bulletin 3967 - Cyanogenetic Plants Of Western Australia, T E H Aplin

Bulletins - 3000 - 3999

This article deals with those native, naturalized and cultivated plants, which by virtue of contained cyanogenetic glycosides, are known to be poisonous or potentially poisonous to livestock in Western Australia.

Cyanogenetic glycosides are chemical compounds which contain a cyanogen (cyanide) radical combined with a sugar molecule. The sugar moiety may differ in glycosides obtained from different plants, and as a consequence glycosides from different plants, containing different sugar moieties, may be given different names.

When a cyanogenetic glycoside is broken down by enzyme action, through injury to the plant or by microbial action in the digestive system of the animal, …


Central Nervous System Toxicity Of Alpha-Chaconine In Rats, Charles Newell Aldous Iii May 1979

Central Nervous System Toxicity Of Alpha-Chaconine In Rats, Charles Newell Aldous Iii

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Effects of alpha-chaconine were examined in the central nervous system on the basis of electrophysiological tests and by assaying for changes in the levels of several known neurotransmitters of the brain. The possibility that brain acetylcholine levels might increase corresponding to acetylcholinesterase inhibition in treated rats was investigated where an increase would suggest that the anti-acetylcholinesterase activity of alpha-chaconine was physiologically significant.

Various doses of alpha-chaconine were given to rats prepared for physiological tests. Some symptoms were observed at relatively low doses (8 to 10 milligrams per kilogram). These included constriction of abdominal muscles, respiratory impairment, and sedation. At the …


The Toxicity, Metabolism And Distribution Of Carbaryl In Three Species Of Labops With And Without Piperonyl Butoxide Treatment (Hemiptera:Miridae), Deifalla H. Osman May 1979

The Toxicity, Metabolism And Distribution Of Carbaryl In Three Species Of Labops With And Without Piperonyl Butoxide Treatment (Hemiptera:Miridae), Deifalla H. Osman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbaryl toxicity, metabolism, and distribution in adults of three species of grass bugs from the genus Labops were studied in relation to species, sex, and treatment with piperonyl butoxide. LC50 values for 8 hour exposure periods ranged from 0.02-0.14, 0.03-0.3, and 0.2-0.7 μg carbaryl/vial for L. utahensis, L. hirtus, and L. hesperius respectively. The males were more susceptible to carbaryl than females. Males of L. utahensis were more susceptible than L. hirtus and L. hesperius respectively.

The synergist difference values (LC50 of carbaryl alone - LC50 values of carbaryl after piperonyl butoxide treatment) were measured. …


The Covalent Interaction Of Hepatic Metabolites Of The Insecticide Chlordane With Cellular Macromolecules In The Rat And Mouse In Vitro, Alan A. Brimfield May 1979

The Covalent Interaction Of Hepatic Metabolites Of The Insecticide Chlordane With Cellular Macromolecules In The Rat And Mouse In Vitro, Alan A. Brimfield

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This investigation addressed several aspects of the covalent interaction of metabolites of the insecticide chlordane with cellular macromolecules in vitro. Microsomal preparations from the liver of mice and rats were used and covalent binding to microsomal protein and RNA or to added calf thymus DNA was studied. Pure 14C-labelled cis- and trans-chlordane isomers as well as an isomeric mixture (14C-cis-chlordane plus 14C-trans-chlordane 3:1, w:w) were used as substrates for the in vitro system. Biochemical parameters investigated included inhibition of microsomal mixed-function oxidase and epoxide hydratase plus the induction of these enzymes by pretreatment with chlordane …


A Rapid And Specific Gas Chromatographic Analysis For Cysteine-S-Sulfonate To Determine The Distribution Of Sulfite In Mammalian Plasma, Joseph Don Debethizy May 1979

A Rapid And Specific Gas Chromatographic Analysis For Cysteine-S-Sulfonate To Determine The Distribution Of Sulfite In Mammalian Plasma, Joseph Don Debethizy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It has been shown in previous studies that when sulfite is absorbed by rabbits via either inhalation of SO2 or oral exposure to sulfite, the hydrated form, bisulfite, interacts with plasma disulfides where it is suspected to be in the form, cysteine-S-sulfonate. A rapid and specific gas chromatographic analysis procedure for cysteine-S-sulfonate has been developed to better study the distribution of sulfite in biological systems. Sulfonated proteins are enzymatically hydrolyzed to ensure stability of the acid labile S-sulfonate disulfide. The hydrolysate is then applied to a 6 cm cation-exchange column and eluted with 0.1 N HCl which elutes the …


Proceedings Of The Conference On Environmental Law -- Toxic Substances, William & Mary Law School Feb 1979

Proceedings Of The Conference On Environmental Law -- Toxic Substances, William & Mary Law School

One-Time Conferences: Programs

Held on February 9-10, 1979 at William & Mary Law School.

Funded by the Virginia Environmental Endowment.

Symposium Participants (in order of appearance): Maurice B. Rowe, William R. Moore, Louise Burke, William F. Gilley, James Douglas, Manning Gasch, Jr., Barbara Bitters, Robert Jackson, James Ryan, Robert R. Merhige, Jr., Gus Steph, Steven D. Jellinek, Frederick R. Anderson, Luther Carter, Peter Barton Hutt, Richard Voight, Richard Merrill, George Taylor, Richard Fleming, Hargis, Richard N. Velde, Susan B. King, Jacob Clayman, Nicholas Ashford, James Rogers, Charles O'Connor, Donald F. Hornig, Devra Davis, Scott C. Whitney, and Denis J. Brion.


The Distribution Of Cadmium, Chromium And Lead In Crabs, Clams And Oysters From Calcasieu Estuary, Louisiana, Fritz Jaenike Jan 1979

The Distribution Of Cadmium, Chromium And Lead In Crabs, Clams And Oysters From Calcasieu Estuary, Louisiana, Fritz Jaenike

Masters Theses

In November 1978, specimens of oysters (Crassostrea virginica), clams (Rangia cuneata), crabs (Callinectes sapidus) and water and sediment samples were collected from Calcasieu Estuary, Louisiana. The concentrations of cadmium, chromium and lead were determined in the samples with an inductively coupled argon plasma direct reading emission spectrophotometer. Crab claw muscle, gill and carapace tissues were analyzed separately. Oysters and clams were separated into shell and whole soft tissue samples which were analyzed separately. The concentration order of the metals in crab carapace and in oyster shells was similar to that of the sediments, (Pb …


The Effect Of Selenium On The Toxicity Of Methyl Mercury In Medaka Embryos, Peter H. Krauth May 1978

The Effect Of Selenium On The Toxicity Of Methyl Mercury In Medaka Embryos, Peter H. Krauth

All-Inclusive List of Electronic Theses and Dissertations

The purpose of this research was to investigate the effect of selenium upon methyl mercury poisoning in Medaka fish (Oryzias latipes) embryos. Selenium has been shown to provide a protective mechanism against mercury poisoning in some adult animals. Three experiments were done. In the first, selenium and methyl mercury were put directly in the growing medium of the eggs. In the second experiment, selenium was included in the diet of the parent fish. In the third part, methyl mercury exposure was delayed three days. The results of the first experiment were quite dramatic and showed a significant difference when selenium …


Toxicological And Biochemical Investigations Of Alpha-Chaconine In Potato (Solanum Tuberosum L. ) Tubers: Physiologic Disposition And Tissue Binding, And Inhibition Of Tissue Cholinesterases And Isoenzymes, Sydney Obodoechina Alozie May 1977

Toxicological And Biochemical Investigations Of Alpha-Chaconine In Potato (Solanum Tuberosum L. ) Tubers: Physiologic Disposition And Tissue Binding, And Inhibition Of Tissue Cholinesterases And Isoenzymes, Sydney Obodoechina Alozie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The distribution, absorption, metabolism and tissue binding of radioactivity were studied in hamsters after oral and intraperitoneal administration of alpha-chaconine- (3H). The material was well absorbed from the gastrointestinal tract and nearly 22 percent of the label was excreted via urine and feces in 7 days. The excretion was higher in urine (21 percent) than in feces ( < 1 percent). Tissue concentrations of radioactivity peaked at 12 hours following oral administration, with the highest concentrations found in lungs, liver, spleen, skeletal muscle, kidney and pancreas, with heart and brain containing moderate amounts. Concentrations of radioactivity in tissues following intraperitoneal administration were significantly higher than those observed after oral treatment. Excretion of chloroform-soluble products in the feces was 10 times higher than that of the chloroform-insoluble metabolites after both oral and intraperitoneal administration. In the urine, the activity was predominantly in the chloroform-insoluble form and the chloroform-soluble metabolites were relatively minor in amounts (0.27, 0.85, and 2.45 percent versus 0.005, 0.14 and 0.19 percent of dose for 12, 24 and 72 hours, respectively). After 7 days, the chloroform-soluble metabolites in urine increased to 20 percent of the excreted radioactivity, while the amount of chloroform-insoluble metabolites was less than 1 percent. Subcellular distribution of the labeled compound indicated the highest concentration of radioactivity in the nuclear and microsomal fractions of brain, liver and heart tissues. A small amount of radioactivity, shown by a minor peak, was also observed in the fractions between the mitochondrial and microsomal fractions on a sucrose gradient. Binding of radioactivity was observed in brain, testes, kidney, lung, liver and heart. All of the label in the brain appeared to be in the bound form. The results indicated that alpha-chaconine is slowly absorbed from the gastrointestinal tract after oral administration, and persists in various tissues, much of it in bound (non-extractable) form (in nuclear and microsomal fractions).

Excretion of alpha-chaconine- (3H) and its metabolites was investigated after oral and intraperitoneal administration in hamsters. The separation of the glycoalkaloid and its metabolites in feces and urine was accomplished by thin-layer chromatography. An increase in the concentration of excreted …


Cytogenetic Test Of Captan And Triethylenemelamine In Mouse Bone Marrow, Stephen M. Fry Apr 1977

Cytogenetic Test Of Captan And Triethylenemelamine In Mouse Bone Marrow, Stephen M. Fry

Honors Theses

Following a single non-toxic i.p. injection with 0.5 or 1.0 mg triethylenemelamine/kig a significant increase in chromosome aberrations in mouse bone marrow was observed 6, 12, 30, but not 54 h after treatment. A single i.p. injection with 250 mg captan/kig caused up to 68% lethality above controls, but no significant increase in chromosome aberrations after the same time intervals. One metacentric chromosome was observed 6, 30, and 54 h after captan treatment among 300, 300, and 101 metaphase spreads respectively, whereas none appeared in 1495 control spreads.


Poisonous Garden Plants And Other Plants Harmful To Man In Australia., T E H Aplin May 1976

Poisonous Garden Plants And Other Plants Harmful To Man In Australia., T E H Aplin

Bulletins - 3000 - 3999

A number of commonly grown garden plants and many weeds found in gardens are know to be poisonous. Many species found outside garden situations are also harmful to man. All of these are potentially dangerous, particularly to children who are more likely to chew them. This bulletin has been complied in response to frequent requests for information on poisonous plants, particularly in relation to human poisonings.


Mercury Levels In Muscle Tissue Of Stream-Dwelling Fish, Tom Frost Jan 1976

Mercury Levels In Muscle Tissue Of Stream-Dwelling Fish, Tom Frost

Masters Theses

No abstract provided.


Pesticide Residues In The Illinois Wild Turkey, John M. Bridges Jan 1975

Pesticide Residues In The Illinois Wild Turkey, John M. Bridges

Masters Theses

Adipose tissue from 55 turkeys, killed during the 1974 hunting season in southern Illinois, was grouped by age and location of the birds, and the pesticide concentrations in them were determined by gas/liquid chromatography. Twelve different pesticides were identified in the samples with only four, total DDT, heptachlor epoxide, toxaphene, and linuron, being present in all samples. Concentrations ranged from 0.02 ppm to 0.88 ppm.


Cerebrospinal Fluid Pressure In Weanling Rabbits With Chronic Plumbism, R.C. Hall Jr., H.I. Frier, R.S. Bartlett, J.E. Rousseau Jr. Dec 1974

Cerebrospinal Fluid Pressure In Weanling Rabbits With Chronic Plumbism, R.C. Hall Jr., H.I. Frier, R.S. Bartlett, J.E. Rousseau Jr.

Storrs Agricultural Experiment Station

No abstract provided.


The Great Potato Debate, James D. Hudson Jul 1974

The Great Potato Debate, James D. Hudson

Honors Theses

Anencephaly and spina bifida cystica are two of the most common severe congenital malformations consistently observed in human populations. Both represent defects in the neural tube and share a significant number of similar epidemiological associations among them, occupational class, geography, sex ratio, maternal age, year and season of the year. In anencephaly most of the brain and upper skull never form usually resulting in death within a few hours of birth. Spina bifida cystica is a malformation of the spinal cord often causing paralysis, vulnerability to infection, and early death. In 1972, Dr. J.H. Renwick presented a controversial hypothesis which …


The Effect Of Thermal Increases On The Acute Toxicity Of Copper And Hexavalent Chromium To Channel Catfish (Ictalurus Punctatus), Alan Kirk Millis Jan 1974

The Effect Of Thermal Increases On The Acute Toxicity Of Copper And Hexavalent Chromium To Channel Catfish (Ictalurus Punctatus), Alan Kirk Millis

Masters Theses

48-hr, 96-hr, and incipient median tolerance limits of channel catfish (Ictalurus punctatus Rafinesque) to copper and hexavalent chromium were determined at temperatures of 50, 60, 70, and 80 F. Standard static bioassay procedures were used. The incipient TLm for copper ranged from 0.56 ppm to 2.15 ppm and from 22.5 to 39.5 ppm for hexavalent chromium. The 48-hr and 96-hr results were somewhat higher. The highest resistance for both metals occurred at 70 F. At 80 F, however, there was a sharp decrease in tolerance. Increased oxygen consumption and opercular movement offer a possible explanation since they would …


Pesticide Effects In A Simulated Soil Ecosystem, Raymond J. Samp Jan 1974

Pesticide Effects In A Simulated Soil Ecosystem, Raymond J. Samp

Masters Theses

The screening of pesticides to determine which were most inhibitory to bacteria was accomplished by testing the effects of 10 pesticides on 9 different organisms using the disk assay method. Results showed that Gram positive bacteria were more sensitive to all pesticides tested than were the Gram negative bacteria. In addition, the hormone herbicides were found to be the most inhibitory to these bacteria and 2,4-D (2,4-dichlorophenoxyacetic acid), a hormone herbicide, was chosen for subsequent in vivo studies.

A soil perfusion apparatus was used to determine the effects of 2,4-D in a typical soil ecosystem. Bacterial plate counts and nutrient …