Increased world-wide interest in reducing the carbon-footprint of human activities has driven the coal-fueled energy industry to transition to a natural gas fueled future. Coupled with the continually increasing energy demand, the interest in alternate sources of natural gas has gained momentum. Microbially enhanced coalbed methane (MECBM), which aims at microbially converting in situ coal to methane provides one such alternate source of natural gas. Feasibility of MECBM as a viable technology is two-pronged, focusing on associated microbiology, and flow-governing reservoir response. The general advance of research in this area has thus far been from a microbial perspective, where coal-to-methane bioconversion has been successfully reported for several coal types worldwide. However, insights into reservoir properties governing flow and transport of fluids in a MECBM reservoir is missing. Given that coal is both the source and reservoir rock of the produced biogenic methane, a sound knowledge of the effect of bioconversion on flow governing properties of coal is decisive from a production perspective. Evaluating the flow governing reservoir response of a MECBM reservoir is the focus of the work presented in this dissertation. In order to investigate the effect of bioconversion on the Darcian flow regime existing in the natural fractures in coal, two experimental studies were undertaken. First, variation in coal’s flow governing micro- and macro- porosity was investigated using high-resolution scanning electron microscopy. The observed changes were quantified and the expected change in permeability of coal post-bioconversion was estimated. In the second set of experiments, the sorption-induced-strain response of coal pre- and post-bioconversion was studies. Finally, the experimental data was used to model and predict the geomechanical-coupled flow behavior of a MECBM reservoir during bioconversion and production of the produced biogenic methane. Experimental results from the imaging study revealed that bioconversion results in swelling of the coal matrix. This reduces the cleat (macroporous fracture) aperture post-bioconversion, reducing the permeability of the coal significantly. This validated the recently reported results, where measured permeability of coal packs and coal cores dropped by ~70% post-bioconversion. Bioconversion, however, resulted in increase in the cleat width of fractures greater than 5 microns wide, which constituted <5% of the fractures imaged. This is indicative of the possibility of enhanced reservoir performance in artificially fractured coal formations or, ones with wide-aperture fractures, like depleted coalbed methane (CBM) reservoirs and abandoned mines. Investigation into the sorption-induced-strain response of coal revealed suppression of the strain response post-bioconversion. Results from helium and methane flooding revealed that bioconversion softens the coal matrix, reducing the Langmuir pressure and strain constants post-bioconversion. The modeling exercise revealed that the depletion induced the permeability increase commonly associated with producing CBM will be suppressed post-bioconversion. Detailed analysis of the behavioral variation in multiple reservoir parameters was used to define the ideal condition, beyond which the reservoir flow during biogenic methane production improved. Additionally, a rating system is proposed, which can be used to rank coal deposits to rate their suitability for bioconversion from a flow perspective.

In this study, we experimentally elevated levels of octopamine and serotonin in an orb-weaving spider, and observed the effects on the antipredator behavior thanatosis (death feigning), activity level, and running speed. We found that octopamine significantly shortened the duration of thanatosis, and its effect wore off over 24 h. We also found that serotonin significantly lengthened thanatosis, but in this case, the effect persisted for over 24 h. Neither octopamine nor serotonin affected the general activity or running speed of the spiders. To our knowledge, this is the first study to directly explore the role of biogenic amines on a specific antipredator behavior in spiders. Given that spiders must be both aggressive toward prey, yet wary of predators, we believe that this system will be an outstanding model to explore connections between behavioral ecology and neurochemistry.

Zeolite catalysts of three types (H-ZSM-5, Fe-ZSM-5 and H-Beta) were tested in the catalytic co-conversion of rapeseed cake and safflower oil into bio-fuel. This low pressure process was carried out at the temperatures of 350 and 400 °C. The yields and compositions of the product mixtures depended on the catalyst nature and the process temperatures. The produced organic phases consisted mainly of hydrocarbons, fatty acids and nitriles. This mixture possessed improved characteristics (e.g. heating value, water content, density, viscosity, pH) compared with the bio-oils, making possible its application as a bio-fuel. The most effective catalyst, providing the highest yield of organic liquid phase, was the highly acidic/wide-pore H-Beta zeolite. The products obtained on this catalyst demonstrated the highest degree of deoxygenation and the higher HHV (Higher Heating Value). The aqueous liquid phase contained water-soluble carboxylic acids, phenols and heterocyclic compounds.

The aim of this study was to examine behavioral and biochemical effects of nafadotride, the new dopamine D3 receptor antagonist, and to compare it with haloperidol (dopamine D2 receptor antagonist) and clozapine (predominate dopamine D4 receptor antagonist). Each drug was injected to adult male Wistar rats intraperitoneally, each at a single dose and for 14 consecutive days. Thirty minutes after single or last injection of the examined drugs, the following behavioral parameters were recorded: yawning, oral activity, locomotion, exploratory activity, catalepsy and coordination ability. By HPLC/ED methods, we determined the effects of the examined antagonists on the levels of biogenic amines in striatum and hippocampus: dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 3-methoxytyramine (3-MT), 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and noradrenaline (NA). Additionally, DA and 5-HT synthesis rate was determined in striatum and 5-HT in hippocampus. The results of the study indicate that nafadotride, the dopamine D3 receptor antagonist, has a behavioral and biochemical profile of action different from that of haloperidol but partially similar to that of clozapine.

Sociality shapes patterns of senescence, evidenced by the remarkable lifespan plasticity of social insect queens and workers. Ants, exemplars of eusociality, provide diverse systems to explore the sociobiology of senescence by examining how sterile workers partition colony labor over their lifespans, and how neurobiological factors affect transitions among social roles and age-related task performance efficacies. Integrating sociobiology, senescence theory, and neurobiology, I examined the relationship of chronological age and social behavior during the ~140-day lifespan of workers of the ant Pheidole dentata. I critically analyzed programmed senescence in respect to the sociobiology of worker longevity and evaluated how large colony size achieved through selection for extended worker lifespan enhances colony fitness. My study found no support for worker programmed senescence. Further testing senescence theory, I determined if workers declined behaviorally as they aged due to increased apoptotic cell death and changes in synaptic complexes associated with higher-order processing in the brain. Using robust behavioral assays I found aging was not correlated with declines in sensory responsiveness or motor functions associated with foraging, nursing, and prey-capture tasks, or activity level and phototaxis. Old minor workers (95 days) followed pheromone trails for greater distances than 20-day old minors and showed higher activity levels, suggesting improvement in behavioral performance. Neural substrates likely underscoring task performance were maintained with age: synaptic complex density was constant and apoptosis was unchanged with age. Sensory and motor control brain regions did not show age-related increases in neurodegeneration. Worker spatial location predicted social role independent of age: foragers exhibited higher activity levels and more aggressive predatory behavior than nurses. Serotonin and dopamine titers increased from 20 to 120 days but showed no clear correlation with social role. Pharmacological manipulations of brain serotonin had no effect on brood care, predatory response, activity, or phototaxis. Finally, I assessed arborization of a serotonergic neuron hypothesized to underscore task performance to determine how aging across subcastes influences neuronal structure. Major workers showed greater branching complexity than minors and an age-related increase in arbor complexity. P. dentata workers appear to show negligible behavioral and neural senescence throughout their lifespans.

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 1.4x10-4, 4.0x10-4, and 9.4x10-5 M, respectively, for NE uptake while the IC50's for 5HT uptake were 1.9x10-4, 6.0x10-4, and 3.3x10-4 M, respectively. Maximal inhibition was 60-100 percent at 10-3 M while the effective concentration range was between 10-4-10-3 M. The remaining test compounds produced no significant inhibition at concentrations up to 10-3 M. K+-dependent phosphatase was strongly inhibited by CH3HgCl, Hg(NO3)2, CdCl2, and Kepone with IC50's of 1.5x10-6, 0.032x10-6, 1.5x10-6, and 13.0x10-6 M, respectively. The effective inhibitory concentrations for these chemicals ranged from 10-7-10-3 M and suggested a specific high affinity inhibition. DFP, paraoxon and acrylamide did not produce a significant inhibition at concentrations between 10-5-10-3 M. A correlation of the phosphatase and monoamide uptake inhibitions, in search of a cause-effect relationship, was not suggested from the data. However, the low affinity inhibition (IC50 greater than 10-5 M) of the NE and 5HT uptake by CH3HgCl, Hg(NO3)2 and Kepone, along with the general shape of the dose-response curve is suggestive of an all-or-none inhibition. The apparent high affinity inhibition (IC50 less than 10-5 M) of the phosphatase demonstrates the specific influences of these compounds can have on enzymatic processes. Such enzymatic inhibition could be of critical importance if these neurotoxicants were able to penetrate the synaptosomal or even neuronal membrane and gain access to the metabolic and synthetic machinery.

No description available.

Low levels of biogenic amines occur naturally, but high levels (FDA sets 50 ppm of histamine in fish as the maximum allowable level) can lead to scombroid poisoning. Amines in general are difficult to analyze by Gas Chromatography (GC) due to their lack of volatility and their interaction with the GC column, often leading to significant tailing and poor reproducibility. Biogenic amines need to be derivatized before both GC and HPLC analyses. The objective of this research was to develop a relatively fast, reproducible method to derivatize and quantitate biogenic amines in fish at trace levels using GC/FID. The derivatizing reagent used in the experiments was propyl chloroformate, useful for aqueous samples. To confirm the identity of six derivatized biogenic amines GC/MS was used. To our knowledge no reference spectra for these derivatives has been published. It was concluded that best results are obtained using a Cold-On-Column (C.O.C.) inlet with a short column (15 meters), thick film stationary phase (ZB-5, 1.00μm df), and with recommendations to cut 40 cm from the inlet end of the column every 25 injections when using C.O.C. Duplicate samples of Atlantic Salmon were analyzed on days 0, 3, and 5. Levels of histamine were below 50 ppm for days 0 and 3, but day 5 showed average levels of 160 pm (cadaverine), 1000 ppm (histamine), and 350 ppm (tyramine). Good precision of six amine stardards at 50 ppm was shown: heptylamine 5.2%, putrescine 5.6%, cadaverine 5.0%, histamine 9.9%, tyramine 5.1%, and spermidine 6.2% RSD. / Master of Science

Changes in histamine, putrescine, and cadaverine concentrations in fresh and stored bluefish (Pomatomus saltatrix) were determined using a new HPLC method. The HPLC method utilized a 5.0% (w/v) trichloroacetic acid (TCA) extraction, pre-column fluorescamine derivitization, and fluorescence detection. The derivatives were stable over 24 h. The 5% TCA extraction produced percent recoveries of 98.6%, 98.7, and 100.0% for histamine, cadaverine, and putrescine respectively. The HPLC process including extraction, derivatization, and HPLC analyses was conducted in less than 45 minutes. Fresh bluefish was found to contain between <1 ppm and 99 ppm histamine, and no cadaverine or putrescine. Fresh bluefish fillets were stored at 5, 10, and 15 degrees C until sensory rejection. Fresh bluefish fillets inoculated with Morganella morganii were also stored at the same conditions. Histamine levels as high as 2200 ppm were observed in the inoculated fish stored at 15 degrees C. Overall, histamine achieved higher levels in the bluefish pieces inoculated with Morganella morganii. Histamine was present in greater amounts than putrescine and cadaverine in the bluefish samples. Histamine levels at each temperature exceeded the 50 ppm advisory level established by the FDA before 100% sensory rejection. Putrescine levels increased at each temperature during storage. Cadaverine was present only in uninoculated bluefish stored at 15 degrees C. Consumer risk from histamine poisoning seems to be the greatest in those fish stored at 5 degrees C where acceptance levels were higher and histamine levels above 100 ppm were observed. The presence of histamine-forming bacteria in fish-processing facilities was studied. Environmental sampling techniques were conducted in the Hampton Roads area of Virginia in fish-processing facilities that regularly handle scombroid fish or other fish which are known to accumulate histamine levels greater than 50 ppm. Surfaces that come into contact with the fish were swabbed and the histamine-forming bacteria from these areas were identified. One isolate each of Klebsiella ozaenae and Vibrio alginolyticus, and two isolates of Aeromonas sp. were found in the processing facilities. The study concluded that histamine-forming bacteria do not make up a large part of the microflora associated with fish-processing facilities. Fishing vessels were also sampled and no histamine-forming bacteria were identified. / Master of Science

Yes / Marrying synthetic biology with synthetic chemistry provides a powerful approach toward natural product diversification, combining the best of both worlds: expediency and synthetic capability of biogenic pathways and chemical diversity enabled by organic synthesis. Biosynthetic pathway engineering can be employed to insert a chemically orthogonal tag into a complex natural scaffold affording the possibility of site-selective modification without employing protecting group strategies. Here we show that, by installing a sufficiently reactive handle (e.g., a C–Br bond) and developing compatible mild aqueous chemistries, synchronous biosynthesis of the tagged metabolite and its subsequent chemical modification in living culture can be achieved. This approach can potentially enable many new applications: for example, assay of directed evolution of enzymes catalyzing halo-metabolite biosynthesis in living cells or generating and following the fate of tagged metabolites and biomolecules in living systems. We report synthetic biological access to new-to-nature bromo-metabolites and the concomitant biorthogonal cross-coupling of halo-metabolites in living cultures. / European Research Council under the European Union’s Seventh Framework Programme (FP7/2007–2013/ERC consolidator grant GCGXC grant agreement no 614779) and ERAIB (Grant no. 031A338A) and H2020-MSCA-IF-2014 Grant no. 659399