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Filby, Amy Louisa. "Molecular effect pathways of endocrine disrupting chemicals in fish." Thesis, University of Exeter, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439828.
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Delacruz, C. Ligia. "The effect of natural toxicants and other chemicals on the kidney." Thesis, University of Surrey, 1988. http://epubs.surrey.ac.uk/847359/.
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Repeated administration of ochratoxin A (OTA) caused renal morphological dose-related changes, that were associated with proximal tubular and glomerular damage the latter showing oedema and prominent PAS staining suggestive of glomerular basement membrane thickening. On the other hand, the combined administration of repeated doses of OTA and aflatoxin B[1] (2. 5 mg and 100 ug per kg, respectively), appeared to have a synergistic effect, characterized by severe disruption of proximal tubules and general morphological derrangement of the glomerulus, involving intense and faint staining nuclei (suggestive of cell necrosis) and cytoplasmic vacuolation, which was not seen with either toxin alone. When clinical biochemical parameters were measured after repeated administration of a low dose of OTA, enzymuria, glucosuria, polyuria and proteinuria were observed, with glucose and alkaline phosphatase as the most sensitive parameters. Metabolic studies performed in vitro showed that isolated pig and rat glomeruli incorporate different amino acids linearly for several hours at different rates and perform oxidative metabolism of glucose and fatty acids to CO[2] also linearly. For pig glomeruli the order of amino acid incorporation was LEU >> PRO = HIS > LYS > GLY and for rat glomeruli it was TRP >> PHE > TYR = LEU > PRO > HIS. The same amino acids were incorporated in a similar way in rat tubules, but the incorporation rate is 10-fold lower. When de novo synthesis of protein by pig glomeruli exposed to different chemicals was assessed, using proline (PRO) as the precursor, adriamycin (ADR) and ethacrynic acid (ETA) inhibited protein synthesis more than 2-bromoethanamine (BEA) and streptomycin (STR), and much more than puromycin aminonucleoside (PAN). When isolated rat glomeruli were exposed to low concentrations of OTA, there was a generalized inhibition on de novo synthesis of protein from the six amino acids tested and the aromatic amino acids (TRP, TYR and PHE) were more sensitive to OTA effect than PRO. Low concentrations of OTA (10 - 100 uM) enhanced glomerular and tubular glucose metabolism to CO[2] and only high concentrations of the mycotoxin (1000 uM) caused significant inhibition of glomerular and proximal tubular linolenic acid metabolism.
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Quinn, Amie L., and University of Lethbridge Faculty of Arts and Science. "The impacts of agricultural chemicals and temperature on the physiological stress response in fish." Thesis, Lethbridge, Alta. : University of Lethbirdge, Faculty of Arts and Science, 2007, 2007. http://hdl.handle.net/10133/676.
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Fish are exposed to multiple stressors in their environment. The interactive
effects of pesticide exposure and increased temperature on the physiological stress
response were investigated in a comparative field study with cold-water (whitefish,
Prosopium williamsoni) and cool-water (sucker, Catostomus) fish from the Oldman
River, Alberta, Canada, and in a laboratory study with rainbow trout, Oncorhynchus
mykiss. Physiogical stress indicators were measured, and exposure to pesticides was
estimated using acetylcholinesterase (AChE) inhibition. Species-specific differences in
AChE activities and responses of the physiological stress axis were detected in whitefish
and suckers, suggesting that whitefish are a more sensitive species to temperature and
pesticide stress. In vivo Dimethoate exposure inhibited AChE activity in various tissues
and disrupted the physiogical stress response. Commercial Dimethoate, in vitro, caused a
decrease in viability and cortisol secretion while pure grade Dimethoate did not. The
results from this study can be used in predictions of fish vulnerability to stress.ix, 137 leaves : ill. ; 29 cm.
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Li, Jing Adela, and 李晶. "Temperature-dependent toxic effects of selected chemicals on marine organisms." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/211051.
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Anthropogenically driven climate change not only results in rising of sea temperature but also leads to more frequent and longer-lasting cold and heat waves. Meanwhile, coastal marine ecosystems are constantly challenged by increasing threats of chemical pollution. Temperature and chemical stressors can jointly affect the livelihood of marine organisms, but their combined effects are still poorly understood. Therefore, this study aimed to investigate the effects of thermal stress and chemical exposure on the marine medaka Oryzias melastigma, copepod Tigriopus japonicus and rotifer Brachionus koreanus. The four selected chemical contaminants included copper sulphate pentahydrate (Cu), dichlorophenyltrichloroethane (DDT), triphenyltin chloride and copper pyrithione. It was hypothesized that marine organisms are more susceptible to chemical exposure at both cold and warm extremes.
In vivo acute ecotoxicity tests were conducted over a wide temperature range to ascertain the relationship between thermal stress and chemical toxicity. For O. melastigma larvae, the lowest toxicity occurred at an optimum temperature range; the chemical toxicity further increased with temperature increase or decrease from this optimum, and exacerbated at extremely low and high temperatures. For T. japonicus and B. koreanus, the chemical toxicity generally increased with increasing temperature. Such inter-species dissimilarities were possibly due to differences in the uptake route, detoxification mechanism, avoidance behaviour and physiological response between the fish and the copepod or rotifer.
Experiments were conducted to evaluate the temperature-dependent physiological and biochemical responses, and thermal tolerance of O. melastigma larvae. The growth in the fish larvae showed an inverse and negatively skewed V-shape relationship with temperature, with a significant reduction in performance at both low and high thermal extremes. A mismatch between demand and supply of oxygen and energy under extremely cold and warm conditions was probably the primary cause of growth inhibition and metabolic impairment, leading to a temporary adaptation by a shift to anaerobiosis and an induction of heat shock proteins (HSPs).
Temperatures at both cold and warm extremes increased toxicities of DDT and Cu to O. melastigma larvae, resulting in restricted growth and interrupted oxygen consumption rate. The fish larvae modulated their metabolic pathway and produced stress proteins (i.e., HSPs and metallothioneins) for adaptation to the combined stress. However, such responses were disrupted by combinations of thermal extremes, in particular high temperature, and high chemical concentration. Most importantly, both DDT and Cu exposure significantly reduced the thermal tolerance of the fish larvae.
The interacting effect of temperature and Cu was also investigated on T. japonicus. The results showed that their combined effect could significantly reduce the survival, lengthen the developmental time and change the sex ratio of the copepod. Transcriptions of several stress-related genes (i.e., glutathione reductase, glutathione S-transferases and HSPs) in the adult T. japonicus were significantly affected by the joint-effect of temperature and Cu exposure, implying that these genes played essential roles in protecting the cellular integrity against the stresses.
This study advanced the understanding on the temperature-dependent toxicity of chemical contaminants to marine organisms, and provided valuable information and empirical models for deriving water quality criteria of chemical contaminants at various temperatures.published_or_final_version
Biological Sciences
Doctoral
Doctor of Philosophy
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Coberly, Samantha W. "The effect of household chemicals on deciduous and permanent tooth class." Thesis, Wichita State University, 2013. http://hdl.handle.net/10057/6807.
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Dental anthropology was wide ranging implications for the field of anthropology. Teeth have become important sources of data about the individual as well as possibly being able to identify them. One problem that can arise is the chemical destruction of teeth whether it be diagenesis in an archaeological context or deliberately in a forensic context. In terms of deliberate destruction of the body several household chemicals are cheap and easily assessable. The purpose of this research is to look at how six household chemicals affect both deciduous and permanent tooth classes. The six chemicals include, Vinegar (acetic acid), Bleach (sodium hypochlorite), Biz (Sodium per carbonate), Lye (Sodium Hydroxide) Ammonia and the control (tap water). The teeth were placed in jars containing the chemical for twenty-four hours. Every hour the weight and mesial/distal length were measured. Of the six chemicals, vinegar affected the teeth the most.Thesis (M.A.)--Wichita State University, Fairmount College of Liberal Arts and Sciences, Dept. of Anthropology
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Turan, Nahid. "The effect of plasticisers and related chemicals on sulphate supply enzymes." Thesis, University of Birmingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433746.
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Howard, Samuel Clarence. "The effect of three holding tank chemicals on anaerobic wastewater treatment." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/45158.
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Sewage-holding tanks aboard recreational boats store human wastes, thereby preventing the direct discharge of wastewater to the aquatic environment. Water-conserving toilets and limited holding tank volumes produce a highly concentrated waste that must be periodically dumped to a wastewater treatment system. Prior to disposal, many boat operators add commercial preparations to control odors produced in their chemical toilets and holding tanks.
The objective of this study was to determine the effects of three holding-tank chemicals on anaerobic wastewater treatment. Specifically, septic-tank performance with respect to effluent total suspended solids (TSS) and chemical oxygen demand (COD) was evaluated. Potential drain-field failure was the concern that led to the selection of TSS and COD. Drain-field failure could result from high solids carry-over or from a high concentration of COD in the effluent which would promote excessive bio-mat growth and clog the system. Laboratory septic tanks were constructed and operated for this evaluation.
Methanol, paraformaldehyde and formaldehyde were each listed as an active ingredient in one of three chemical compounds used by recreational boat owners to deodorize sewage-holding tanks. septic-tank effluent TSS concentrations were not adversely effected by the shockloading with wastewater containing these chemicals. Concentrations expected to be achieved by dilution (20 and 50 percent of the recommended additive dose) resulted in septic-tank effluent COD within an acceptable range, which was determined by operation of a control system. Wastewaters containing these concentrations were not detrimental to the septic-tank treatment system. However, the full manufacturers' recommended dose of the odor control chemicals disrupted the system's ability to degrade COD. At full strength, the para formaldehyde and formaldehyde deodorants were particularly detrimental; no recovery occurred after the two-day shock-dose was completed.Master of Science
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Reed, Susan, of Western Sydney Hawkesbury University, and of Science Technology and Environment College. "Development of method to assess skin contact to chemicals." THESIS_CSTE_XXX_Reed_S.xml, 2001. http://handle.uws.edu.au:8081/1959.7/611.
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Chemical exposure of the skin has become a route of entry of some chemicals into the body and has come under major review in recent times. This research aims to develop a method of estimating skin exposure that is both reliable and non-prohibitive in cost. This involved the design and testing of skin patches adaptable for monitoring skin exposure to chemicals using several different types of absorbents which could be easily worn against skin. The final design of the patch used either activated charcoal or tenax as the absorbing medium. The patches were then desorbed with a solvent in order to analyse the chemicals. The results of the study showed that many skin exposures do not have a direct relationship with inhalation exposures, which is important because currently there are no estimates of the levels of skin exposures that may have potential long term health effects. The patch has proved successful for detecting the presence and determining the amount of chemicals that come in contact with the skin. Charcoal patches have the widest application, but are not suitable for all situations and tenax should be used on these occasions.Doctor of Philosophy (PhD)
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Montambault, François. "The use of Hoe-39866 as a potato-top desiccant /." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61703.
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Weyand, Eric Henry. "The metabolic fate of benzo [a] pyrene in vivo." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/77786.
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[³H]-B[a]P absorption, distribution, metabolism, excretion and macromolecular binding in male Sprague-Dawley rats were investigated following administration by intratracheal instillation through a cannula. [³H]- radioactivity in various organs was determined at timed intervals between 5 and 360 min. Elimination of radioactivity from lungs was biphasic with half-lives of 5 and 116 min. Radioactivity in liver increased rapidly, reaching a maximum of 21% of the dose within 10 min after installation and decreasing thereafter, until less than 5% of the dose was detected at 360 min. Radioactivity in intestinal contents accounted for 45% of the dose 360 min after installation. Carcass accounted for 15-30% of the dose within the time intervals investigated. Toxicokinetic parameters to describe B[a]P disposition following intratracheal administration were similar to those following intravenous injection of B[a]P. HPLC was used to identify various types of metabolites in lungs, liver, and intestinal contents at selected times after B[a]P instillation. Notably, quinones were at highest concentrations in both lung and liver 5 min after installation, accounting for 12 and 7% of organic extractable material, respectively. Covalent binding of B[a]P metabolites to DNA, RNA, and protein at 6 hrs after installation was also quantified for lung and liver. There was extensive binding of metabolites to RNA while much lesser amounts of metabolites were associated with protein and DNA in both organs. Six B[a]P:DNA adducts were detected in lung, while only three such adducts were detected in liver.
³
Biliary excretion of B[a]P was investigated in SpragueDawley rats, Gunn rats, hamsters, and guinea pigs following instillation of [³H]-B[a]P. [³H]-B[a]P was administered at concentrations ranging from 6 ng to 380 μg and biliary radioactivity was monitored for 6 hrs. In addition, tissue distribution of radioactivity was determined. Species differences in biliary excretion of B[a]P and/or metabolites were detected. Rats and guinea pigs, but not hamsters, exhibited differences in biliary excretion of low and high doses of B[a]P. Phase II metabolites of B[a]P in bile were quantified for all species. The majority of these metabolites were glucuronides and thio-ether conjugates. Enterohepatic circulation of B[a]P biliary metabolites was investigated in Sprague-Dawley rats.Ph. D.
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Tomic, Tjasa. "Functionalised cellulosic materials for hydrolysis free reactive dyeing and the fixation of effect chemicals." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498845.
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Seggio, Joseph A. "Chronic Ethanol Modulated Photic and Non-photic Phase Responses in Syrian Hamster and C57BL/6J Inbred Mouse." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/SeggioJA2009.pdf.
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Dwyer, Suzanne. "Effects of Neonatal Clomipramine Treatment on Photic and Non-Photic Circadian Phase Shifting in Rats." Fogler Library, University of Maine, 2000. http://www.library.umaine.edu/theses/pdf/DwyerSM2000.pdf.
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Amoako, Daniel Kwasi. "Cyclopiazonic acid changes the mode of excitation-contraction couplingin acetylcholine-stimulated bovine tracheal smooth muscle." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1996. http://hub.hku.hk/bib/B3121387X.
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Yeung, Chiu Wai. "Neurotoxicological effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin on cultured neurons." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/529.
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Li, Yuhong, and n/a. "Effect of alcohol exposure in early gestation on brain development." University of Otago. Department of Anatomy & Structural Biology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070502.100319.
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Fetal alcohol spectrum disorders (FASD), caused by maternal alcohol consumption during pregnancy, has been extensively studied in the human. Animal studies show that alcohol exposure during very early development may result in severe brain damage, often incompatible with a postnatal life. However, for surviving offspring it is unknown whether they suffer long term brain damage. The final assembly of the mature brain results from a controlled balance between proliferation of glial and neuronal precursors and programmed cell death. The overall aim of the current study was to use a physiologically relevant mouse model to assess the acute and long-term effects of binge alcohol exposure on the early embryo, to simulate human pregnancy at the third week of gestation when pregnancy may be undetected.
A number of paradigms were used to assess the acute dose-response effect, the blood alcohol concentration (BAC) profile and the extent of cell death following alcohol exposure on gestational day (G) 7.5. The exposure paradigms were single binge IG6.5, IG4.5, IP4.5, or an extended binge IG4.5+, IG3.0+. Two control groups were Con6.5 and Con4.5+. Acute cell death was determined using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), activated caspase-3 staining, and transmission electron microscopy. Cell proliferation was investigated using S-phase immuno-labeling, bromodeoxyuridine (BrdU) birthdating and immuno-detection (BrdU/anti-BrdU). The long-term effects were investigated at G18.5 and postnatal day (PN) 60. Unbiased stereological methods were used to assess the effect of ethanol exposure at G7.5 on neocortical volume, cell number and density of neurons, glial cells, and capillary cells at PN60.
The first principal finding of the present study was that binge ethanol exposure during gastrulation resulted in acute apoptotic cell death in the ectoderm of the mouse embryo. Cell death was dependent on both peak BAC and the duration of elevated BAC. Significant increased cell death (TUNEL labeling) was observed in groups IG6.5 (9.43 � 2.08%) and IG4.5+ (8.97 � 2.12%) compared with control groups Con6.5 (2.14 � 0.09%) and Con4.5+ (2.81 � 0.36%). There was no significant increased cell death in ethanol exposed groups IG4.5 (3.43 � 0.45%), IP4.5 (3.68 � 0.67%), or IG3.0+ (1.72 � 0.24%). TEM analysis revealed that cell death exhibited characteristics of the apoptotic pathway.
The second principal finding of the present study was that binge ethanol exposure during gastrulation resulted in acute arrested proliferation in the ectoderm of the mouse embryo. The S-phase proliferation was significantly decreased within the whole ectoderm in the ethanol exposed group IG6.5 (45.58 � 2.34%) compared with control group Con6.5 (62.08 � 3.11%).
The third principal finding of the present study was that binge ethanol exposure during gastrulation induced the long term effect of laminate disorganization in the neocortex. The incidence of abnormal lamination was 87.5% in IG6.5 compared with 16.7% in IG3.0+ and 14.3% in Con6.5. Although ethanol exposure increased embryonic reabsorption, decreased litter size, and increased abnormal offspring, neocortical volume, and the total number of neurons, glial cells, and capillary cells was not affected. The total number (10⁶) of neurons, glial cells, and endothelial cells respectively was 12.221 � 0.436, 4.865 � 0.167, and 2.874 � 0.234 in IG6.5; 11.987 � 0.416, 4.942 � 0.133, and 2.922 � 0.130 in IG3.0+; and 11.806 � 0.368, 5.166 � 0.267, and 3.284 � 0.217 in controls, at PN60.
These results provide important information pertinent to fetal outcome for those women who drink heavily in early pregnancy. The results also demonstrate the importance of the pattern of ethanol exposure and blood alcohol concentration in determining the magnitude of ethanol�s teratogenic impact. Ethanol exposure on G7.5 that resulted in a high transient BAC, induced disorganized neocortical lamination, indicative of a permanent structural change. This disruption may result in altered neocortical function and requires further investigation.
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Worsham, Jessica Nicole. "5-HT3 Receptor Ligands and Their Effect on Psychomotor Stimulants." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1054.
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Drug abuse and addiction are considered to be a result, at least in part, of the rewarding effects produced by increasing dopamine levels. 5-HT3 serotonin receptors have been shown to indirectly affect dopamine levels. Therefore, the effect of the 5-HT3 receptor partial agonist, MD-354, on the actions of psychomotor stimulants was analyzed in mouse locomotor activity assays to determine whether MD-354 is working through a 5-HT3 receptor agonist or antagonist mode of action. Studies with (+)amphetamine and (+)methamphetamine in combination with MD-354 indicated MD-354 is either devoid of action or is behaving similar to the 5-HT3 receptor antagonist, ondansetron. This effect could be occurring centrally; however peripheral effects can not be discounted. In combination with cocaine, MD-354 behaved similar to the 5-HT3 receptor agonist, SR 57227A, known to act both centrally and peripherally. This difference between central and peripheral effects could account for the different modes of action observed with MD-354. Studies also involved synthesis of potentially brain-penetrant carbamate analogs of MD-354, and QSAR to assist in validating a 5-HT3 receptor agonist pharmacophore.
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Chan, Sai Yen Victor, and 陳世欽. "Effect of homocysteine on nitric oxide production in cardiomyocytes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31970321.
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Nongauza, Sinethemba Aubrey. "An investigation of the effect of co-solvents on the hydrothermal liquefaction of microalgae biomass." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/21667.
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The study introduces and demonstrates the viability of the continuous flow reactor (CFR) system for the production of bio-crude oil (BCO) from wet microalgae. Preliminary experiments conducted in the CFR system in hot compressed water (HCW) were successful in converting wet microalgae into liquid BCO. However, the synthesis and aggregation of high boiling point (HBP) components of BCO and the accumulation of char in the tubular piping of CFR system were identified as the limiting factor to the viability of the system. The aggregation of HBP components and the accumulation of char result to system blockage which prevents the continuous flow of the liquefaction product mixture in the CFR system. Inhibiting the reactions leading to the formation of HBP components and char will improve the performance of the CFR system. Therefore, the study seeks to incorporate co-solvents in the liquefaction reaction media in an attempt to inhibit or minimize the prevalence of HBP components of BCO. As such, different co-solvents were screened for their influence on improving the quality of BCO with respect to its boiling point profile (BPP), initial and final boiling point, as well as the amount of char recovered from each experiment. Only one co-solvent was chosen for further exploration in the CFR system. Batch liquefaction reactor’s (BLR) made up of stainless steel were used to carry out the co-solvent screening experiments. These experiments were carried out at a constant temperature (280 °C), pressure (75 bar), and co-solvent concentration (10 wt.%), at varying residence times. Solvent extraction with dichloromethane (DCM) was performed on the liquefaction product mixture to separate the products, viz. BCO, char and water soluble components. The extracted BCO was analysed through simulated distillation (SimDis) to obtain the BPP. The BPP properties of the BCO samples, from different liquefaction media, and the amount of char recovered were highly influenced by the addition of a co-solvent. The final boiling point (FBP) of tetralin, heptane, and n-octanol BCO products were significantly reduced to below 500 °C for all tested residence times except at 20 minutes. The residence time also proved to be influential in the processing of wet microalgae. n-Octanol was selected as the optimal performing co-solvent and was used for the continuous liquefaction of wet microalgae in the CFR system. The CFR system was modified by adding a co-solvent feed line into the continuous system since n-octanol was insoluble in water. The n-octanol pump was set at different flow rates, 0.2, 0.3, and 0.4 g/min, which resulted in a concentration of about 10 wt.% in the reactor feed. The concentration of n-octanol had a significant influence on the BPP of BCO components. The FBP’s were reduced with an increase in n-octanol concentration. The initial boiling point (IBP) of n-octanol BCO was increased to just above 100 °C which was required for the stability of the BCO product. The components of BCO were identified by GCMS. n-Octanol also proved to affect the composition of the BCO with respect to its components. HCW BCO components were significantly different from those identified from n-octanol BCO. A second co-solvent (tetralin) was used to prove whether the difference on the components of BCO was affected by n-octanol. The results proved that indeed the addition of different solvents in liquefaction reaction media favours the formation of different components. The amount of char formed was also reduced when using a co-solvent. A decrease in the oxygen/nitrogen compounds was also observed in the presence of a co-solvent, thus improving BCO properties.
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Holcroft, Joanna (Joanna Mary Steward). "Effect of Anolyte on broiler performance." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/18708.
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Thesis (MPhil)--Stellenbosch University, 2003.ENGLISH ABSTRACT: A farm in Zimbabwe (Farm A) obtains its water for tbe poultry operations from tbe Makavusi River that is heavily contaminated with bacteria and performance results are thereby reduced. Anolyte is a Russian invention that claims to have bactericidal effects that could be beneficial to broilers. The aim of this research is to investigate the effect of Anolyte on production profits of broilers given water of poor quality by carrying out a number of trials. Trials that were conducted are basic in vitro tests on Anolyte within the laboratory, water analysis on water supply to the broiler section (both chemical and bacteriological), and a detailed trial within an experimental trial site comparing broiler performance results with different chemical water treatments and different dilutions of Anolyte. Broiler chicks from different hatcheries (Hatchery A and Hatchery B) were also compared. Performance results were based on growtb rate, mortality, feed conversion ratios (FCR), performance efficiency factors (PEF) and profit margin comparisons. Results showed that in tbe laboratory, Anolyte had an antibacterial activity. In the broiler performance trial on Hatchery B broilers, the live weights at forty two days of age in broilers given 15% Anolyte differed from other treatments (P<0.05) other than 10% Anolyte (P > 0.05). However, the FCR and mortalities did not differ (P > 0.05) between treatments. In the trial on Hatchery A broilers to 42 days of age, growth rates in broilers given 15% Anolyte differed from tbe control, Chematron and 20% Anolyte (P < 0.05). However, the FCR and mortalities did not differ between (P>0.05) treatments. In comparing chicks from different hatcheries, Hatchery B broilers differed (P < 0.05) from Hatchery A broilers in live weights at 42 days on 10% Anolyte, 15% Anolyte and on Chematron treatments. However, tbe cumulative mortalities and FCR did not differ (P > 0.05) between the Hatchery B and Hatchery A on any treatment. When comparing profitability, tbe treatment that had the greatest margin in comparison to tbe control (untreated drinking water) was 15% Anolyte for both tbe Hatchery B and Hatchery A trials.
AFRIKAANSE OPSOMMING: 'n Plaas in Zimbabwe, (Plaas A) verkry water, vir hul pluimvee bedryf vannuit die Makavusi rivier. Die rivier is swaar besmet met bakterië en as gevolg daarvan verhoed dit dat hulle hul volle opbrengs potential bereik. Anolyte is 'n Russiese uitvindsel wat aanspraak maak daarop dat dit bakteriëdodende effekte besit wat tot die bevordering van slaghoenders kan lei. Die doel van die navorsing is om Anolyte op proef te stel aangaande produksie profyt op slaghoenders waaraan swak kwaliteit water verskaf is. Verskeie toetse is uitgevoer n1. 'n basiese 'in vitro' toets in samewerking met die laboratorium, water ontleding op water wat aan die slaghoender seksies verskaf is (beide chemikalies and bakterieologies) asook 'n intensiewe proefnemeing waarin die verskeie obrengs resultate, van chemikaliese behandelde water en verskillende verdunnings van Anolyte, met mekaar vergely is, in 'n experimetele navorsings eenheid. Slaghoender kuikens van twee verskillende broeihuise (n1. Broeihuis A en Broeihuis B) is ook met mekaar vergelyk. Die resultate is gabasseer op groei tempo, sterftes, voer omsettings verhouding, opbrengs geskikthied faktore asook vergelykings op wins. Laboratorium navorsing het bevestig dat Anolyte wel antibakteriese aktiviteit getoon het. Terwyl in die proefneming op Broeihuis B slaghoenders, het die lewende gewig van hoenders, op 42 dae van ouderdom, waaraan 15% Anolyte verskaf is, verskil van ander behandelings (P<0.05) met die uitsondering van 10% Annolyte (P>0.05). Alhoewel die voer omsetting verhoudings en sterftes nie in die verskillende behandelings verskil het nie. In die proefnemeing op Broeihuis A slaghoenders tot 42 dae van ouderdom, het die ontwikkeling van slaghoenders, waaraan 15% Anolyte verskaf is, verskil van die kontiole, Chematron en 20% Anolyte. Die voer omsettings verhoudings en sterftes het egter geen verskil getoon tussen die verskeie behandelings nie. Resultate van die vergelyking tussen die kuikens uit die twee verskillende broeihuise, het getoon dat die Broeihuis A en Broeihuis B lewensgewigte, op 42 dae van ouderdom, wel met mekaar verskil het met 10% Anolyte, 15% Anolyte sowel as die Chematron behandelings. Daar was egter geen verskil, (P>O.05) tussen die twee tipes aangaande elke tipe se saamgestelde sterftes en die voer omsettings verhoudings, in welke behandeling nie. Die vergelykings op wins het getoon dat die behandeling met die grootste brulo marge, die was van 15% Anolyte in vergelyking met die kontiole (onbehandelde drinkwater) vir beide die Broeihuis A en die Broeihuis B proefnemings.
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Wei, Juntong. "Mass spectrometry-based metabolomics to unveil the polybrominated diphenyl ether-47 induced alteration in breast carcinoma." HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/661.
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Based on the findings from breast cancer cells and nude mouse assays, we noticed that fatty acid metabolism was influenced by BDE-47 exposure. To have a comprehensive understanding of the impact, we performed targeted metabolomics analysis of fatty acids. Short-chain fatty acids (SCFAs) and hydroxylated short-chain fatty acids (OH-SCFAs) are crucial intermediates related to a variety of diseases, such as bowel disease, cardiovascular disease, renal disease and cancer. We developed a global profiling method to screen SCFAs and OH-SCFAs by tagging these analytes with d0/d6-N, N-dimethyl-6,7-dihydro-5H-pyrrolo[3,4-d] pyrimidine-2-amine (d0/d6-DHPP) and UHPLC-MS/MS in parallel reaction monitoring (PRM) mode. The derivatization procedure was simple and rapid. The targeted compounds could be derivatized within three minutes under mild condition and analyzed without the need of further purification. The derivatization significantly improved the chromatographic performance and mass spectrometry response. The d6-DHPP tagged standards were used as internal standards, which remarkably reduced the matrix effects. The use of high resolution PRM mode made it possible to identify unknown SCFA and OH-SCFA species. The developed method was successfully applied to the analysis of mouse feces, serum, and liver tissue samples harvested from the breast cancer nude mice that had been exposed to BDE-47. By using the developed method, 40 analytes (10 SCFAs and 30 OH-SCFAs) were characterized. Semi-quantitative analysis indicated that the exposure of BDE-47 to the mice altered the SCFA and OH-SCFA metabolism, especially in the high dose group. In addition, medium- and long-chain fatty acids (MLFAs) are essential energy sources in cells and possess vital biological functions. Characteristics of MLFAs in biosamples can contribute to the understanding of biological process and the discovery of potential biomarkers for relevant diseases. However, there are obstacles of the MLFAs determination because of the poor ionization efficiency in mass spectrometry and structural similarity. Herein, a derivatization strategy was developed by labeling with d0-DHPP and detecting with UHPLC-MS/MS in multiple reaction monitoring (MRM) mode. The parallel isotope labeled internal standards were generated by tagging d6-DHPP to MLFAs. The simple and rapid derivatization procedure and mild reaction conditions greatly reduced the potential of MLFA degradation. With the methodology, the chromatography performance was greatly improved, and the mass spectrum response was enhanced up to 1, 600 folds. Finally, the developed derivatization method was applied to serum samples to analyze the alteration of MLFAs induced by BDE-47 exposure in breast cancer nude mice. The semi-quantitative results demonstrated that the BDE-47 exposure significantly influenced the MLFA metabolism. Together, mass spectrometry-based targeted and nontargeted metabolomics of in vitro and in vivo studies suggested that BDE-47 impacted multiple metabolic pathways and was positively associated with breast tumor growth in mice. This study might further our understanding of the health risks of BDE-47 to breast cancer.;Polybrominated diphenyl ethers (PBDEs) are commonly used to prevent the development of fire in various factory products. Due to the adverse effects on human health and bio-accumulation capacity, PBDEs are considered as one kind of persistent organic pollutants. 2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is one of the most frequently detected PBDE congeners in humans. Although numerous studies have shown the close connection between BDE-47 and human health, few reports were related to breast carcinoma. In vivo study of the association between BDE-47 and breast cancer was also scarce. In this study, both in vitro and in vivo experiments were conducted to explore the influence of BDE-47 to breast cancer. Firstly, we performed the in vitro study by exposing different concentrations of BDE-47 (5, 10 µM) to MCF-7 breast cancer cells. Nontargeted metabolomics analysis was conducted by using ultra-high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS). Results showed that the toxicity to MCF-7 cells gradually increased when the concentration of BDE-47 exceeded 1 µM in the medium. Pyrimidine metabolism, purine metabolism and pentose phosphate pathway (PPP) were the most influenced metabolic pathways, and the metabolites in the three metabolic pathways were significantly downregulated. Moreover, the increase of reactive oxygen species was detected by using the 2',7'-dichlorodihydrofluorescein diacetate staining assay. Results suggested that the BDE-47 induced oxidative stress by downregulating the NADPH generation in PPP. The pyrimidine metabolism and purine metabolism might be downregulated by the downregulation of mRNA transcripts. Therefore, BDE-47 could induce oxidative stress in breast cancer cells by inhibiting PPP and disordering the metabolism of the entire cell subsequently. Secondly, we constructed a breast cancer nude mouse model, performed in vivo exposure of BDE-47 to the mice, and conducted mass spectrometry-based metabolomics and lipidomics analysis to investigate the metabolic changes in mice. Results showed that the tumor sizes were positively associated with the dosage of BDE-47. Metabolomics and lipidomics profiling analysis indicated that BDE-47 induced significant alterations of metabolic pathways in livers, including glutathione metabolism, ascorbate and aldarate metabolism, and lipids metabolism, etc. The upregulations of phosphatidylcholines and phosphatidylethanolamines suggested the membrane remodeling, and the downregulations of Lyso-phosphatidylcholines and Lyso-phosphatidylethanolamines might be associated with the tumor growth. Targeted metabolomics analysis revealed that BDE-47 inhibited fatty acid β-oxidation (FAO) and induced incomplete FAO. The inhibition of FAO and downregulation of PPARγ would contribute to inflammation, which could promote tumor growth. In addition, BDE-47 elevated the expression of the cytokines TNFRSF12A, TNF-α, IL-1β and IL-6, and lowered the cytokines SOCS3 and the nuclear receptor PPARα. The changes of cytokines and receptor may contribute to the tumor growth of mice.
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Lau, Wai Kit Jaeger. "Developmental expression of N-methyl-D-aspartate and gamma-aminobutyric acid receptors in the rat basal ganglia." HKBU Institutional Repository, 2004. http://repository.hkbu.edu.hk/etd_ra/535.
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Lam, Wai Chi Rebecca. "Expression of metabotropic glutamate receptors in the rat striatum during postnatal development." HKBU Institutional Repository, 2003. http://repository.hkbu.edu.hk/etd_ra/528.
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Kile, Joanna L. (Joanna Le). "The Reproductive Consequences of Carriers of Methylenebisacrylamide-Induced Balanced Reciprocal Translocations in Mus Musculus." Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc500402/.
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N,N'-methylenebisacrylamide (MBA) was studied because of its effectiveness in inducing heritable translocations in germ cells of male mice. The health impact of translocations was studied through anatomical analysis of the progeny of semisterile translocation carriers. As expected, the semisterility of translocation carriers resulted primarily from embryonic death during periimplantation stages due to unbalanced chromosome sperm segregants. Among conceptuses that survived to mid- and late-gestation stages, there was an increased incidence of developmental anomalies including fetal death and phenotypic defects. These abnormalities are associated with unbalanced chromosome complements that allow survival to the later stages of development.
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Shubat, Pamela Jane. "Monocrotaline toxicity and pulmonary arteries." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184533.
Full textAbstract:
Monocrotaline is a pyrrolizidine alkaloid found in plants implicated in livestock and human poisoning. Laboratory rats given monocrotaline develop pulmonary hypertension and right heart hypertrophy in the weeks following administration of the chemical. Lung weight increases and right heart hypertrophy correlate with increased pulmonary artery pressure. Rats which consumed monocrotaline drinking water (20 mg/l) for only 4 days developed significant increases in lung and heart weights 14 days after exposure began. This exposure was equivalent to a dose of 15 mg/kg. Other treatment combinations of time (0-10 days exposure) and monocrotaline concentration (5-60 mg/l in drinking water) were tested. The accumulative dose calculated for each of the treatment combinations which produced toxicity was in the range of 15 to 20 mg/kg. Monocrotaline injury appears to be cumulative, but organ weight increases reverse once exposure is stopped. As pulmonary hypertension develops and pulmonary arteries hypertrophy, the force with which isolated pulmonary artery segments contract decreases. This is a loss of efficacy rather than potency to the contracting agents KCl, norepinephrine, and 5-hydroxytryptamine. Relaxation of arteries under conditions of potassium-return (a measure of Na⁺/K⁺ ATPase activity) was also altered by monocrotaline treatment. In vivo monocrotaline treatment had little effect on the force of K⁺-return relaxation. However, the rate at which arteries relaxed was significantly decreased following 4 days ingestion of monocrotaline drinking water (20 mg/l). In vitro ouabain treatment and endothelial injury also decreased the rate of K⁺-return relaxation. Another Na⁺/K⁺ ATPase activity, ⁸⁶Rb⁺ uptake, was decreased following monocrotaline treatment only when 5-hydroxytryptamine was present and only uptake associated with the endothelium was affected. These studies utilized a very low exposure to monocrotaline (4 days ingestion of 20 mg/l monocrotaline drinking water or 15 mg/kg) to produce toxicity in rats. Monocrotaline-induced toxicity measured 20 days after treatment included right heart and lung hypertrophy and decreased contractions of isolated pulmonary arteries. Monocrotaline treatment decreased the rate of Na⁺/K⁺ ATPase-dependent relaxation of isolated pulmonary arteries 4 days after treatment began.
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Castillo-Ruiz, Priscila. "Plant activation of different chemicals by tobacco and brassica cell cultures, using the plant cellmicrobe coincubation assay." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39239.
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In this study, the ability of various chemicals to be biotransformed into mutagens by plant cells was investigated. Two thiocarbamate herbicides, diallate and triallate, the sulfonylurea herbicide chlorsulfuron, and the aniline derivative m-phenylenediamine were tested for their ability to revert Salmonella typhimurium (strains TA100 and TA98) in the presence and absence of Nicotiana tabacum (TX1) cell cultures in liquid suspension. Chlorsulfuron and m-phenylenediamine were also tested in the presence and absence of Brassica napus cv. 'Topas' cells. Diallate was found to be activated by TX1 cells into a mutagen that induces base-pair substitution mutations. In the presence of the TX1 plant cell line, chlorsulfuron significantly increased the number of mutations on the strain TA98 of Salmonella. Tobacco TX1 cells did not activate triallate into a mutagen. m-Phenylenediamine was activated into a mutagen by TX1 and Brassica cells as detected by Salmonella TA98. This aniline derivative, in the absence of plant cells and at concentrations higher than 20 $ mu$ Moles/plate, was also able to significantly increase the number of TA98 revertants as compared to the control plants. Finally, Brassica napus cells activated chlorsulfuron into a mutagen that induces frameshift mutations.
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Omami, Elizabeth Nabwile, of Western Sydney Hawkesbury University, of Agriculture Horticulture and Social Ecology Faculty, and School of Horticulture. "Amaranthus retroflexus seed dormancy and germination responses to environmental factors and chemical stimulants." THESIS_FAHSE_HOR_Omami_E.xml, 1993. http://handle.uws.edu.au:8081/1959.7/66.
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A large number of weed seeds in the soil persist because of seed dormancy, and depletion of the seed bank through manipulation of seed dormancy has been suggested as one of the goals in weed control. This study was designed to investigate some of the factors which control dormancy and germination in Amaranthus retroflexus seeds. Germination studies were conducted at different temperatures, and either in continuous white light or in the dark. Higher temperatures increased germination and, although light interacted with temperature, its effect on germination varied with the temperature. In an attempt to determine changes in dormancy during dry storage, two lots of seeds were stored dry at different temperatures. Loss in dormancy increased with an increase in storage temperature and duration, but the time required for maximum germination varied according to the seedlot. Seeds germinated to higher percentages at high temperatures, but storage at higher temperatures and for prolonged duration resulted in seeds gaining the ability to germinate at lower temperatures. Changes in dormancy under field conditions were also examined. Seeds were buried at different depths and for different durations and they all lost viability with time, but this loss was greater in surface-sown and shallowly buried seeds. Dormancy was broken during cold periods and induced as warmer periods progressed. The effects of chemical stimulants on dormancy and germination were investigated. The response of seeds to ethephon and nitrate were assessed at different temperatures either at continuous white light or in the dark. Germination increased with the concentration of the chemicals, and a greater response was observed at lower temperatures. The response to light varied depending on temperatureMaster of Science (Hons)
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Poon, Ming-see Angela, and 潘明施. "Binding of 2[125I]iodomelatonin in the guinea pig spleen: evidence for a direct action of melatonin on themammalian immune system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B31233855.
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Allison, Edwin. "Effects of seed adjuvants on germination and development of onions." Thesis, Cape Technikon, 2001. http://hdl.handle.net/20.500.11838/2000.
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Thesis (MTech (Agriculture))--Cape Technikon, 2001.Onion seeds (cultivar Caledon Globe), and soil into which the seedlings were planted, were treated with various adjuvants including fungicides, a seed disinfectant and a soil sterilant, as well as soil-applied growth stimulants to determine the effect of these on germination of seed, the growth of plants and the storage life of onions obtained. Three sets of germination trials were undertaken in petri dishes, and sets of seed was also sown in deep seed trays. A trial planting was made and the crop graded and stored. Seed was also sown in pots in soil obtained from a commercial undertaking where poor germination had been obtained. A portion of this soil was pasteurised and a portion inoculated with Fusarium spp. Growth of these seedlings was then followed by re-sowing in the same pots using seed of additional cultivars.
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Chidgey, Laura Louise. "An integrated approach to unravel the effect pathways of endocrine disrupting chemicals on the developing zebrafish, Danio rerio." Thesis, University of Exeter, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496171.
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Over the last two decades, a wide range of chemicals in the aquatic environment have been shown to elicit disruptive effects on the endocrine system and, in turn, alter physiological function. However, the underlying mechanisms for these effects remain largely elusive. In this thesis, a molecular approach (using DNA microarrays and RTPCR) was employed to investigate the mechanistic basis for estrogenic disruption in ling the zebrafish (Danio rerio) as a model species.
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Sandoval, Mojica Andres Felipe. "Antifeedant effect of commercial chemicals and plant extracts against Schistocerca americana (Orthoptera: Acrididae) and Diaprepes abbreviatus (Coleoptera: Curculionidae)." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024748.
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Miller, Lana L., and University of Lethbridge Faculty of Arts and Science. "The effects of selenium on the physiological stress response in fish." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2006, 2006. http://hdl.handle.net/10133/397.
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Selenium (Se), an essential element, can bioaccumulate and become toxic. The
main toxicity symptom in fish, teratogenicity, is mediated by oxidative stress; however,
little is known about the effect of Se on the physiological stress response (PSR). The
effects of Se on the PSR and oxidative stress parameters were investigated in rainbow
trout, brook trout, and white suckers. The PSR was activated by acute and sub-chronic
laboratory exposures to NaSeO3, but not exposure to environmental levels of Se.
Species-specific sensitivity to Se may be explained by biochemical differences. Rainbow
trout (exhibit oxidative damage with Se exposure) have greater GSH reserves (cycles
with Se causing oxidative stress) than brook trout. Selenium in agricultural drain water
did not accumulate to dangerous levels in white suckers, but additional stressors (e.g.
pesticides) were present. Differences in sensitivity to Se may alter competitive
interactions between species, changing community compositions and putting additional
pressure on threatened species.xiii, 150 leaves ; 29 cm.
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Mayles, Karen Marie 1957. "Chemical regulation of growth and fruit maturity of Vitis vinifera 'Flame Seedless' using hydrogen cyanamide." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276605.
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The effect of hydrogen cyanamide (H₂CN₂) on budbreak and fruit maturity of 2-year old 'Flame Seedless' table grapes was investigated in a low desert climate in central Arizona. Dormant sprays of H₂CN₂ applied at 2.5 and 5.0% (v/v) concentrations hastened budbreak by at least 16 days with subsequent advancement of fruit maturity by 5 to 10 days. A 5.0% (v/v) dormant application of H₂CN₂ to whole vine, buds only or pruning cuts only advanced budbreak by at least 16 days and advanced fruit maturity by 1 to 5 days, regardless of application site. A more uniform budbreak was observed on H₂CN₂ treated vines, regardless of concentration or site of application when compared to control vines.
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Dann, Andrea B. "The effects of triclosan, 2,4-D, and their by-products on the adrenocortical cells of rainbow trout." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2011, 2011. http://hdl.handle.net/10133/3154.
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The ubiquitous presence of anthropogenic chemicals and their transformation products in surface water represents a toxicological concern from both an ecological standpoint and a human perspective as many of these chemicals are capable of altering hormonal function. Endocrine disrupting compounds can be traced back to numerous sources and may fall under the class of pesticide, industrial chemical, pharmaceutical, personal care product, and/or heavy metals. The adrenal gland is the most common target for endocrine disruptors, although in comparison to the sex steroids, this system has received much less attention in published research. Corticosteroids play a pivotal role in many physiological processes, including immunity, cognitive function, growth, metabolism, reproduction, mineral balance, and blood pressure. A primary cell culture of rainbow trout adrenocortical cells was used to investigate the endocrine disrupting activity of two commonly detected water-borne toxicants, a personal care product, triclosan (TCS), a pesticide, dichlorophenoxyacetic acid (2,4-D), and their transformation products, methyl-triclosan (M-TCS) and dichlorophenol (DCP). Previously, it has been shown that TCS, 2,4-D, and DCP exhibit a potential for endocrine disruption, although it is currently unknown if these chemicals are capable of affecting corticosteroid balance. In this study, all four chemicals showed significant inhibitory effects on corticosteroid synthesis, even though there were considerable differences in their activity. The chemical that exhibited the highest toxicity was 2,4-D, followed by TCS, DCP, and M-TCS. Both parent-compounds proved to be more toxic than their degradation products. More research with suitable test systems is needed to determine the mechanism(s) of action of these corticosteroid disruptors and the health risk that they may present.ix, 139 leaves : ill. ; 29 cm
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Belayneh, Teferi Yeshitela. "Effect of cultural practices and selected chemicals on flowering and fruit production in some mango (Mangifera indica L.) cultivars." Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-01142005-085139.
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Alm, Therese. "Characterization of retention chemicals and their effect on the paper forming process on machine PM4, Billerud Korsnäs Gävle Mill." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-93424.
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In the papermaking industries spots in the finished product is a recurring problem. Billerud Korsnäs have in earlier studies identified poorly optimized retention systems as one of the reasons for these spots. Poorly optimized retention systems will allow for detrimental substances to flow freely in the system, which may cause agglomeration into larger particles that could end up as darker spots in the finished product. The aim of this thesis is to investigate a number of retention systems, consisting of a retention polymer and retention microparticles, and characterize the polymers.The retention aid systems task is to flocculate fibres, fines and fillers along with the colloidal material to improve process parameters. To investigate the retention systems three different retention polymers with different charge densities have been investigated alongside one microparticle. The parameters investigated in this thesis were the retention systems effect on drainage time, turbidity, charge demand and zeta potential. Pulp and white water from PM4 was used to imitate mill conditions.The results showed that the drainage time and turbidity was most effected by the retention aid systems. The polymer with the highest charge yielded the best results. Only minor effects could be detected on charge demand and Zeta potential.
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Davison, Elizabeth L. 1947, and Elizabeth L. 1947 Davison. "Caesalpinia pulcherrima, Calliandra californica, and Justicia specigera: Chemical and environmental regulation of their growth and development." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277127.
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Investigations of three low-water requiring landscape species produced the following results: (1) Although Calliandra californica flowered under photoperiods from 12 to 16 hours, plants produced more elongation under 16 hour days. Plants grew taller and developed greener foliage under irradiances of 600 μmol·m⁻²·s⁻¹. Branching was not stimulated by foliar sprays of BA, PBA, or BA + GA₄₊₇. (2) Caesalpinia pulcherrima increased biomass under 16 hour days, but were stunted and chlorotic under irradiances of 1950 μmol·m⁻²·s⁻¹. Internodal lengths were restricted with drenches of 3.75 mg · pot-1 uniconazole, and plants sprayed with 500 mg·liter⁻¹ PBA developed more axillary branching without negative elongating effects. (3) Justicia specigera gained more height under 12 hour days, and produced greener foliage, more elongation, and faster flowering under irradiances of 600 μmol·m⁻²·s⁻¹. Plants showed restricted internodal elongation and fewer flowers when drenched with 5.0 mg·pot⁻¹ uniconazole, and developed more axillary branching with no detrimental elongation effects when sprayed with 100 mg·liter⁻¹ BA + GA₄₊₇.
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Bull, Kimberly. "Effects of a commercial pentabrominated diphenyl ether mixture on cholinergic parameters in captive mink." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99325.
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Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants that are recognized as global environmental contaminants and a potential health risk. They have been shown to elicit neurodevelopmental toxicity through disruption of the cholinergic neurotransmitter system in rodent models, but the effects of environmentally relevant exposures in wildlife species are unknown. The objective of this study was to assess the effects of the commercial pentabrominated diphenyl ether mixture DE-71 on cholinergic parameters in captive mink (Mustela vison) following dietary exposure of adult females and in utero, lactational and dietary exposure of their offspring. Adult females were fed diets containing 0, 0.1, 0.5 or 2.5 μg/g DE-71 from four weeks prior to breeding through weaning of their kits at six weeks of age. A portion of the weaned kits were maintained on their respective diets through 27 weeks of age. Cholinergic neurochemical biomarkers, including muscarinic acetylcholine receptor (mAChR) and nicotinic acetylcholine receptor (mAChR) binding, cholinesterase (ChE) activity and acetylcholine (ACh) concentration, were assayed in the cerebral cortex, and ChE activity measured in the plasma. Results indicated no significant effects of DE-71 on cholinergic parameters in the cerebral cortex, but a 3-fold increase in ChE activity in the plasma of adult females in the 2.5 μg/g DE-71 group. There were also no direct effects of DE-71 on mAChR or mAChR binding or ChE activity in the enzyme and receptor fractions from the whole brain of untreated mink following in vitro exposure to 0-23.6 nM DE-71. This study demonstrated that environmentally relevant exposures to DE-71 did not affect key parameters of the cholinergic neurotransmitter system in the brain of captive mink.
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Henrico, Daleen (Elsie Magdaleen). "Vergelyking tussen die kodlingmot (Cydia pomonella) se fenologiese ontwikkeling in 'n chemies behandelde-, onbehandelde- en organiese boord in die Wes-Kaap." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50223.
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Thesis (MScAgric)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Codling moth, Cydia pomonella (L.), infested fluit were collected in a sprayed, unsprayed and an organic orchard. The time of emergence was monitored to see if there was selection for a delayed emergence caused by different treatments. Moths from fruit collected in the sprayed and unsprayed orchards in Desember 2001, had a peak emergence during January 2002 and a smaller peak during February 2002. Moths from fruit collected during February 2002 from an organic orchard, had a peak emergence during February 2002 and an extended emergence from diapause until January 2003. Moths from fluit collected during March 2002 had a peak emergence during November 2002 with an extended emergence in the sprayed orchards until January 2003. Delayed emergence from diapause was observed. Not all the moths from diapause emerged during the first flight, but overlapped with the second flight in December and January.
AFRIKAANSE OPSOMMING: Kodlingmot, Cydia pomonella (L.), geïnfesteerde vrugte is in 'n onbespuite, chemies behandelde en 'n organiese boord versamel. Die tyd van motuitkoms is gemonitor om te bepaal of verskillende behandelings dalk seleksie in die motpopulasie kan veroorsaak ten op sigte van 'n vertraagde motuitkoms. Motte uit vrugte wat in die gespuite boorde in Desember 2001 versamel is, het 'n piek uitkoms in Januarie en 'n kleiner een in Februarie 2002 gehad. Motte uit die ongespuite boord se vrugte, het ook 'n piek uitkoms in Januarie 2002 getoon. Motte uit vrugte wat in Februarie 2002 in 'n organiese boord versamel is, het 'n piek uitkoms in Februarie 2002 gehad, met 'n verlengde uitkoms vanuit diapause vanaf Oktober 2002 tot Januarie 2003. Motte uit vrugte wat in Maart 2002 versamel is, het 'n piek uitkoms in November 2002 gehad. Daar was ook 'n verlengde motuitkoms vanaf diapause by die chemies behandelde boorde tot Januarie 2003. 'n Vertraagde motuitkoms vanaf diapause is waargeneem. Die motte vanuit diapause maak nie almal deel uit van die eerste vlug nie, maar oorvleuelook met motte van die tweede vlug wat gedurende Desember en Januarie in die veld voorkom.
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Kolli, Ramya. "Effect of Leaving Ligands of Platinum(II) Diamine Complexes on DNA and Protein Residues." TopSCHOLAR®, 2013. http://digitalcommons.wku.edu/theses/1268.
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Platinum compounds are widely used drugs in cancer treatments. Although DNA is the biological target, reaction of platinum compounds with proteins is also potentially significant. Our objective is to study the effects of leaving ligands on the relative reactivity between 5'-GMP (guanosine 5' phosphate), a key DNA target, and N-Acetyl - L-Methionine (N-AcMet), a key protein target. We have used NMR spectroscopy to monitor reactions with N-AcMet and 5'-GMP added to a platinum complex to see which products are formed preferentially. Previous research showed that both a non-bulky complex such as [Pt(en)(D2O)2]2+ [en=ethylenediamine], and a bulky complex such as [Pt(Me4en)(D2O)2]2+ [Me4en= N, N, N', N'-tetramethylethylenediamine] react more quickly with 5'-GMP than with N-AcMet. To improve the activity of platinum compounds in our current research, oxalates as leaving ligands are used. The results suggest that [Pt(en)(Ox)] [Ox= oxalate] reacts faster with N-AcMet than with 5'-GMP. Also, [Pt(Me4en)(Ox)] reacts slowly with 5'-GMP without N-AcMet and the reaction favors N-AcMet when both ligands are added simultaneously. Interestingly, the formation of the sulfur-oxygen chelate is slow enough to be observable in the oxalate reaction; but the mono product is not independently observed in the dinitrate complex.
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Manglik, Aparna Safety Science Faculty of Science UNSW. "Development of comparitive methods for chemical analysis and in vitro cytotoxicity testing of contaminated sites." Awarded by:University of New South Wales. School of Safety Science, 2006. http://handle.unsw.edu.au/1959.4/25168.
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This project developed methodology for in vitro toxicity assessment of contaminated sites using the Promega?? MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy-methoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay performed on human cells (HepG2 and Skin fibroblasts). The project included the development of a method for extracting contaminants from soil based on leaching and centrifugation. A number of solvents and surfactants were assessed for their suitability as extracting agents. The Zwitterionic surfactant CHAPS ({3[(3-Cholamidopropyl) dimethylammonio] propanesulphonic acid}), which is an irritant in vivo, was found suitable for in vitro toxicity assessment applications. CHAPS was found to be the least toxic surfactant in vitro when tested on skin fibroblasts (NOEC: 1800??577 ppm, IC50: 4000??577 ppm) and HepG2 cells (NOEC: 833??289 ppm, IC50: 5300??287 ppm). The chosen surfactant was used in three different methods for extraction of Toluene and Xylene spiked in 2 g and 10g soil. The combination comprising of 0.1% (s/w) CHAPS and cosolvent 1% (w/w) Isopropanol, at their respective NOEC (No Observed Effective Concentration) toxicity values, showed good recovery of the nonpolar organic compounds in comparison to the recovery by 0.1% CHAPS and 0.5% CHAPS. The study found additive interactions to be the most common form of toxicity for 16 concentration combinations of Formaldehyde (polar), Toluene and Xylene (nonpolar) when compared to predicted toxicity (R2=0.943, P<0.0001). When assessing the in vitro toxicity of unknown (blind) contaminated soil samples, the Hazard Index (HI) predicted from the chemical analyses results showed a relatively good correlation (R2>0.7062, n=26) when compared to the experimental toxicity results on HepG2 cells. Furthermore, the comparison of Australian Health Investigation Levels (HIL) with in vitro toxicity testing gave similar correlation (R2>0.6882, n=26) on HepG2 cells. The overall project suggests the potential application of the zwitterionic surfactant (CHAPS) in sampling contaminants from soils in an in vitro toxicity assessment. This study demonstrates the application of in vitro toxicity assessment using human cells for the prediction of toxic risk as a sentinel to human toxicity from a contaminated site.
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Chu, Yu-Hsuan. "Custom Fluorophores for Investigating the Cellular Uptake Mechanisms and Side-Effects of Pharmaceuticals." PDXScholar, 2015. http://pdxscholar.library.pdx.edu/open_access_etds/2343.
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There is a significant current need to elucidate the molecular mechanisms of the side-effects caused by widely-used pharmaceuticals. Examples include the acute nephrotoxicity and irreversible ototoxicity promoted by the cationic drugs gentamicin and cisplatin. Gentamicin is an aminoglycoside antibiotic used for the prevention and treatment of life-threatening gram-negative bacterial infections, such as tuberculosis and meningitis. Cisplatin is used to treat a broad spectrum of cancers including head and neck, ovarian, cervical, stomach, bladder, sarcoma, lymphoma, testicular cancer and others.
The objective of this study is to design and synthesize rhodamine derivatives that can be used for the construction of geometrically well-defined cationic drug conjugates. The long-term goal is to use the conjugates as tools to aid in elucidating the properties and identities of ion channels involved in the uptake of cationic pharmaceuticals into kidney and cochlear hair cells. This will shed light on the origin and potential prevention of unwanted side effects such as nephrotoxicity and ototoxicity associated with specific cationic drugs.
A series of extended rhodamine analogs with reactive groups for biomolecule conjugation has been synthesized. These fluorophores show similar spectral properties to their prototype, Texas Red succinimidyl ester (TR-SE). However, they contain rigid linkers between the fluorophore and amine-reactive moiety. The resultant gentamicin conjugates of these materials are rigidified enabling one to assess channel pore dimensions without the confounding issue of conjugate folding. Preliminary cell studies are promising, as one observes reduced gentamicin uptake in both kidney and sensory hair cell upon systematically increasing the dimension of the fluorophore. This work has enabled us to tentatively assign the maximum dilated MET channel pore size as between 1.44 nm to 1.56 nm. However, this preliminary finding, though encouraging, needs further validation via ongoing studies with larger diameter fluorophore conjugates,
A cisplatin-Texas Red conjugate has also been synthesized to enable studies of cellular uptake mechanisms. This conjugate preserves not only the spectral properties of Texas Red after conjugation, but also the cytotoxicity of cisplatin. This has been validated in zebrafish. The series of rhodamine probes that have been conjugated to gentamicin should be similarly useful for cisplatin studies. These studies are planned. Additional future work includes the synthesis of semi-flexible (glycol) and flexible (alkyl) linkers to evaluate structure-activity relationships.
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Leduc, Frédéric. "Linking the neuropeptide annetocin with reproductive success of the earthworm Eisenia fetida in two natural soils amended with the wood preservatives chromated copper arsenate (CCA) and alkaline copper quaternary (ACQ)." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82274.
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Chromated copper arsenate (CCA), type C, was largely used as a wood preservative due to its exceptional fungicidal and insecticidal properties. Although this treatment was prohibited for residential purposes in Canada and in the United-States of America, concerns about CCA-treated wood focus on the possible threat on human health and the contamination of the environment, through the leaching of metals from existing structures. The objectives of this thesis are (1) to assess the effects of metals leached from CCA- and ACQ-treated wood on the survival, the growth and the reproductive success of the earthworm Eisenia fetida (Annelida, Oligochaeta), and (2) to evaluate if annetocin, a neuropeptide linked to reproduction, could be used as a biomarker of ecotoxicological responses of the worm E. fetida when exposed to metals from the CCA treatment. Ecotoxicological tests with E. fetida were carried out according to the protocol ISO-11268-2. (Abstract shortened by UMI.)
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Zhang, Qian Amy, and 張倩. "Ecotoxicities and ecological risks of irgarol 1051 and its related s-triazine compounds in tropical marine ecosystems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41757956.
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The Best PhD Thesis in the Faculties of Dentistry, Engineering, Medicine and Science (University of Hong Kong), Li Ka Shing Prize,2007-2008published_or_final_version
Biological Sciences
Master
Master of Philosophy
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Smith, Bill J. "The role of epoxidation in 4-vinylcyclohexene-induced ovarian toxicity." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185059.
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The basis for the species difference between B6C3F1 mice (susceptible) and Fischer 344 rats (resistant) to 4- vinylcyclohexene (VcH)-induced ovarian tumorigenicity was investigated. Greater than 95% of a single oral 400 mg/kg dose of [¹⁴C]VCH was eliminated in 48 hr by mice and rats. Approximately 50-60% of the administered dose was excreted in the urine, while the remaining 30-40% of the dose was expired as organically soluble radioactivity. VCH-treated mice had dramatically higher blood concentrations of the VCH metabolite VCH-1,2-epoxide compared to VCH-treated rats. Furthermore, mouse hepatic microsomes catalyzed the conversion of VCH to VCH-1,2-epoxide at greater rates than rat hepatic microsomes. The destruction of oocytes was used as an index of ovarian toxicity to compare the potency of VCH and VCH epoxides in the mouse and rat. VCH markedly reduced the number of small oocytes in mice while no detectable change in oocyte number occurred in rats. Epoxide metabolites of VCH destroyed oocytes in both species at lower doses than VCH. Inhibition of VCH epoxidation reduced VCH-1,2-epoxide blood levels and partially protected mice from VCH-induced ovarian toxicity. Thus, the conversion of VCH to epoxides and the subsequent destruction of oocytes are critical steps in the induction of ovarian tumors by VCH. Rats may be resistant because the amount of VCH converted to epoxides is insufficient to destroy oocytes. The biochemical basis for the species difference in the rate of VCH epoxidation by hepatic microsomes from mice and rats was investigated. studies using inducers and inhibitors of certain cytochrome(s) P450 showed that hepatic microsomes of female mice perform VCH epoxidation at greater rates than rats because of the constitutive expression of P450 IIA and lIB forms. Hepatic microsomes of human females perform VCH epoxidation at lower rates than rats. This suggests that if the rate of epoxidation of VCH by the liver is the most important factor determining susceptibility to VCH toxicity then the rat may better model the response of humans exposed to VCH than mice.
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Hardin, Joanna, Stacy D. Brown, Phillip Scheuerman, and Kurt Maier. "Imidacloprid Persistence, Mobility, and Effect on Soil Quality and Ecosystem Function." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/5267.
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Ott-Reeves, Ellen (Ellen Theresa). "In Situ Hybridization of 70 kD Heat Shock Protein mRNA in a Rat Model of Ethanol Self-Administration." Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc332564/.
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Sucrose fading was used to initiate self-administration of ethanol on an FR4 schedule in male Fischer 344 rats. Rats showed low response rates for ethanol alone. After administration of liquid diet containing ethanol, ethanol intake increased over levels prior to administration of the liquid diet. In situ hybridization compared mRNA for the inducible or constitutive 70 kD heat shock proteins in ethanol and nonethanol rats. Both inducible and constitutive mRNAs were found in nonethanol and ethanol tissues. In peripheral organs, radiolableling was higher in ethanol tissue. In brain regions, nonethanol tissues showed higher radiolabeling.
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Dzedze, Ntombiyesicelo. "Fermentation rate, yeast protein and sensory profiles of wines from fungicide treated Chenin Blanc grapes." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2820.
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Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2018.Fungal diseases in vineyards are one of the main causes leading to economic losses within the viticultural sector and are continuously increasing over years. The most common of these fungal diseases are powdery mildew, downy mildew and grey mould. Commercial fungicides to treat the above-mentioned diseases are available and their usage is regulated under Act 36 of 1947 to comply with Good Agricultural Practises (GAP). However, the application of less-harmful, natural alternative fungicides to control vineyard diseases are currently an important research focus since the demand for organic products by consumers and retail companies are increasing. However, fungicide residues can alter the fermentation process and prevent some biochemical pathways of yeast metabolism involved in phenolic and/or aroma compound production that are critical for sensory quality. Therefore the aim of the study was to investigate the effect of fungicide treatments on the fermentation rate, yeast proteins expressed, aroma compounds released and sensory profile of wines produced. In the study, Chenin Blanc grapes treated with chemical and natural fungicides (1x treatment and 2x treatment) under Good Agricultural Practises (GAP) were used to produce small-scale wines and laboratory-scale fermentations. Laboratory-scale fermentations were conducted in duplicate using the commercial Saccharomyces cerevisiae (S. cerevisiae) Active Dry Wine Yeast (ADWY) strains VIN 13 and VIN 7. The fermentations were monitored by frequently weighing until they stabilised (CO2 weight loss). Small-scale wines were produced using the commercial S. cerevisiae ADWY strain VIN 13 only. Wines were made according to the standard Nietvoorbij experimental winemaking procedure. At the end of fermentation, lees samples were plated onto Yeast Extract Peptone Dextrose (YPD) agar and colonies grown were subjected to CHEF gel electrophoresis to confirm that the S. cerevisiae yeast strain inoculated at the beginning of the fermentation completed it. Moreover, fermenting wine samples, collected at the start (lag phase) and at end of fermentation (stationary phase), were subjected to protein extraction, quantification and characterisation in order to investigate fermenting wine yeast proteins. Furthermore, the final wines were subjected to chemical analyses as well as measurement of aroma enhancing metabolites (esters, higher alcohols, fatty acids and thiol compounds) using GC – FID and MS. Additionally, duplicate samples of the wines were evaluated sensorially by a trained panel of 12 winemakers and researchers, using an unstructured line scale. Wines were compared to the control wine according to visual (colour), flavour (tree fruit, tropical fruit, and wine foreign), taste (body mouthfeel, acidity) and overall quality. The data collected from the study was statistically analysed using a two-way analyses of variance (ANOVAs) and subject to a multiple factor analysis (MFA). From the results obtained in the above study, it was concluded that yeast strains used for winemaking completed the fermentations at a similar rate to their respective controls. In addition, small-scale cellar fermentations showed that fungicide treatments (1x treatment and 2x treatment) compared to the controls had no notable negative effects on wine aroma and sensory profiles although differences were observed in the proteins expressed after the fermentation. Overall, the fungicide treatments did not negatively affect the yeast performance, yeast protein expressed, aroma compounds released and sensory profiles of the wines produced. Further studies are recommended on other white as well as red wine grape cultivars to fully assess the effects of the fungicides.
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Dean, Timothy Neal. "The immunotoxic effects of aldicarb." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41612.
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Gola, Nontuthuzelo Pearl. "A comparison of biomarkers in assessing the combined effects of pesticide mixtures on non-target soil invertebrates." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16327.
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Thesis (MSc)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Agricultural environments are usually contaminated with mixtures of antropogenically introduced chemicals as a result of pesticide spraying, which can affect beneficial, nontarget soil invertebrates, such as earthworms negatively. Most studies on mixture toxicity have focused on interactions of chemicals with similar structures and mechanisms. However, chemical mixtures may occur as conglomerates of diverse structures and toxicological mechanisms in the environment. This study was aimed at assessing the effects of pesticides singly, and in a mixture, on earthworms, using lifecycle parameters (growth and reproduction) and biomarkers (neutral red retention (NRR) assay and acetylcholinesterase (AChE) inhibition) as endpoints. Thus, to determine whether any interactions occurred between the pesticides as shown by the measured endpoints. Another aim was to validate the use of the chosen biomarkers for assessing mixture toxicity. The pesticides used were from three groups: organophosphates, heavy metal-containing pesticides and pyrethroids. From these three groups, four of the most commonly used pesticides in the orchards and vineyards of the Western Cape, South Africa, were chosen, namely chlorpyrifos (organophosphate), azinphos-methyl (organophosphate), copper oxychloride (heavy metal-containing fungicide) and cypermethrin (pyrethroid). Earthworms were exposed in the laboratory to a range of concentrations of chlorpyrifos and copper oxychloride singly, and in 1:1 mixtures of these pesticides in artificial soil, for four weeks. After the exposure period, the biomass change was determined as measure of growth, and cocoon production, hatching success and number of hatchlings per cocoon were determined as measures of reproduction. Growth (biomass change) and reproduction (cocoon production) were affected by the highest concentration treatment (20mg/kg) of chlorpyrifos, but copper oxychloride and the mixture of the two pesticides showed no observable effects on lifecycle parameters. Dose related effects on NRR times were however determined for both pesticides and the mixture. Dose related effects on AChE activity were found for chlopyrifos and the mixture of the two pesticides, but not for copper oxychloride. Short-term exposures (48 hours) of earthworms to the following pesticides in artificial groundwater: chlorpyrifos, copper oxychloride, azinphos-methyl, cypermethrin, chlorpyrifos-copper oxychloride, chlorpyrifos -azinphos-methyl and chlorpyrifos-cypermethrin, were done followed by the determination of AChE inhibition. Dose related effects were exhibited on the AChE activity of earthworms exposed to chlorpyrifos, a mixture of chlorpyrifos and copper oxychloride, azinphos-methyl, and a mixture of azinphos-methyl and chlorpyrifos. Copper oxychloride, cypermethrin and the mixture of chlorpyrifos and cypermethrin had no effect on AChE activity. Earthworms died at the highest exposure concentration of the mixture of chlopyrifos and cypermethrin. Results have shown that although the pesticides did not cause observable effects on lifecycle parameters, there were effects at subcellular and biochemical level, as shown by the biomarkers. Mixtures of pesticides, in some instances, affected earthworms differently from their single components, indicating interactions between the pesticides in mixtures, as shown by the measured endpoints. The NRR assay proved to be a good general biomarker of soil contamination, and the AChE activity could also be a valuable tool in assessing the effects of organophosphate mixtures and mixtures of organophosphates and pesticides from other groups.
AFRIKAANSE OPSOMMING: Nie-teiken organismes, soos erdwurms, word negatief beïnvloed deur mengsels van antropogeniese chemikalieë in landbou-omgewings. Die meeste studies wat handel oor die toksisiteit van chemiese mengsels het tot dusver gefokus op chemikalieë van dieselfde aard en met dieselfde meganismes van werking. Mengsels van chemiese stowwe kan egter as konglomerate van 'n verskeidenheid strukturele eienskappe en met verskillende toksiese meganismes in die omgewing aangetref word. Tydens die studie is gepoog om die effekte van enkel pestisiede sowel as mengsels daarvan op erdwurms te bestudeer, deur van lewensloop kenmerke (groei en voortplanting) en biomerkers (neutraalrooi retensietyd - NNR en inhibisie van asetielcholienesterase -AChE) as eindpunte gebruik te maak. 'n Verdere doel van die studie was om vas te stel of daar enige wisselwerkings tussen die verskillende pestisiede plaasvind, soos aangetoon deur die gemete eindpunte, en verder ook om die gebruik van die gekose biomerkers as maatstawwe van mengseltoksisiteit te evalueer. Die pestisiede wat gebruik is, is van drie verskillende groepe afkomstig: organofosfate, swaarmetale en piretroiede. Van hierdie drie groepe is vier van die pestisiede wat vry algemeen in boorde en wingerde in die Weskaap, Suid-Afrika, gebruik word, geïdentifiseer. Hierdie stowwe is chlorpyrifos (organofosfaat), azinphos-metiel (organofosfaat), koperoksichloried (swaarmetaalbevattende fungisied) en sipermetrien (piretroied). Erdwurms is in die laboratorium aan 'n reeks konsentrasies van chlorpyrifos en koperoksichloried as enkel toksikante en as 1:1 mengsels in kunsmatige grond, vir vier weke blootgestel. Voor en na die blootstellingsperiode is die biomassa van die wurms, as maatstaf van groei, bepaal en kokonproduksie, uitbroeisukses en getal nakomelinge per kokon bepaal as maatstawwe van voortplantingsvaardigheid. Groei (biomassaverandering) en voortplanting (kokonproduksie) is beinvloed deur behandeling met die hoogste konsentrasie (20 mg/kg) chlorpyrifos, terwyl geen effek van koperoksichloried of die mengsel van hierdie twee pestisiede gevind is nie. Daar is gevind dat beide die pestisiede, enkel en in die mengsel, die NRR tye beinvloed het. Die AChE aktiwiteit is beinvloed deur chlorpyrifos en die mengsel, maar nie deur die koperoksichloried nie. Korttermyn blootstellings van erdwurms (48 uur), in kunsmatige grondwater, van erdwurms aan chlorpyrifos, koperoksichloried, azinphos-metiel en sipermetrien as enkel toksikante en mengsels van chlorpyrifos-koperoksichloried, chlorpyrifos-azinphos-metiel en chlorpyrifos-sipermetrien, is gedoen en gevolg deur die bepaling van AChE inhibisie. Koperoksichloried, cypermetrien en die chlorpyrifos-sipermetrien mengsel het geen waarneembare effek op die AChE aktiwiteit gehad nie ?????. Die erdwurms wat blootgestel is aan die hoogste konsentrasie in die mengsel van chlorpyrifos-sipermetrien het doodgegaan. Die resultate het getoon dat die pestisiede nie in die korttermyn die lewensloopkenmerke in enige waarneembare mate geaffekteer het nie maar daar was effekte op sellulêre en biochemiese vlakke soos aangetoon deur die biomerkers. Sommige mengsels van die pestisiede het die erdwurms verskillend van die enkelstowwe geaffekteer. Daar het dus wisselwerking tussen sommige van die pestisiede wat in mengsels aangewend is, plaasgevind, soos aangetoon deur die gemete eindpunte. Die NRR toets, as breë-spektrum biomerker was 'n goeie maatstaf van kontaminasie in grond en daar is aanduidings dat die AChE aktiwiteit, as 'n spesifieke biomerker, 'n nuttige maatstaf kan wees om die effekte van organofosfaatmengsels en mengsels van hierdie chemiese groep en die van ander chemikalieë aan te toon.