In order to explore south Arabia's role in the migratory episodes leaving Africa to Eurasia and back, high-resolution Y-chromosome analyses of males from the United Arab Emirates (164), Qatar (72) and Yemen (62) were performed. The distribution of specific haplogroups (E3bl-M35 and J1-M267) and their microsatellite-based age estimates in southern Arabia offer additional insight on their dissemination. With the exception of Yemen, southern Arabia displays high diversity in its Y-haplogroup substructure and share similarities with populations along the eastern coast of the Gulf of Oman, possibly serving as a coastal corridor for migrations. Elevated rates of consanguinity may have had an impact in Yemen and Qatar, which experience deficiencies in their ratios of observed to expected heterozygosity at 15 hypervariable autosomal STR loci. Higher diversity along the Gulf of Oman may be due to trade emanating from the kingdom of Oman involving East Africa, southern Pakistan and western India.

Current forensic comparisons of soil most often rely upon physical characterizations. We hypothesized that bacterial community profiles obtained by Amplicon Length Heterogeneity-Polymerase Chain Reaction (ALH-PCR) of the 16S rRNA genes would provide discriminating data for soil comparisons. Dual extractions and replicate amplifications were performed on each soil. Chemical characterization by elemental analysis, pH, moisture content, percent Carbon and percent Nitrogen were performed. Supervised classification of the microbial community profiles using a Support Vector Machine (SVM) learning tool was over 95 % accurate labeling a microbial community profile to its originating soil type. By comparison, the chemical analysis data yielded accuracies between 40 and 77 %. The results of this study support the application of this method in the comparison of casework size soil samples. Results of this study may also justify the future development of a database of microbial community profiles for inferring the possible origin of unknown soil samples.

The drugs studied in this work have been reportedly used to commit drug-facilitated sexual assault (DFSA), commonly known as "date rape". Detection of the drugs was performed using high-performance liquid chromatography with ultraviolet detection (HPLC/UV) and identified with high performance-liquid chromatography mass spectrometry (HPLC/MS) using selected ion monitoring (SIM). The objective of this study was to develop a single HPLC method for the simultaneous detection, identification and quantitation of these drugs. The following drugs were simultaneously analyzed: Gamma-hydroxybutyrate (GHB), scopolamine, lysergic acid diethylamide, ketamine, flunitrazepam, and diphenhydramine. The results showed increased sensitivity with electrospray (ES) ionization versus atmospheric pressure chemical ionization (APCI) using HPLC/MS. HPLC/ES/MS was approximately six times more sensitive than HPLC/APCI/MS and about fifty times more sensitive than HPLC/UV. A limit of detection (LOD) of 100 ppb was achieved for drug analysis using this method. The average linear regression coefficient of correlation squared (r2) was 0.933 for HPLC/UV and 0.998 for HPLC/ES/MS. The detection limits achieved by this method allowed for the detection of drug dosages used in beverage tampering. This method can be used to screen beverages suspected of drug tampering. The results of this study demonstrated that solid phase microextraction (SPME) did not improve sensitivity as an extraction technique when compared to direct injections of the drug standards.

Ascertaining the genetic relationships between Austronesian populations is pivotal to understanding their dispersal throughout the islands of the Pacific and Indian Oceans. The Austronesian expansion dates to approximately 6,000 years ago and from the linguistic and archeological evidence, the origin of this dispersal appears to be Taiwan. In this study, six polymorphic point mutation loci were studied in Taiwanese aborigines and compared with 32 other populations. The genetic relationships were characterized by maximum likelihood analysis, principal component maps, centroid gene flow plots, expected heterozygosities, power of discrimination values and pair wise G-tests. Following these analyses, it was apparent that genetic similarities existed between the Atayal and the Chinese, whereas the Ami displayed similarities with the Native Americans. Thus, the Atayal have little or no affinity for the Ami and other Austronesian populations. The large genetic differences between the two groups most likely arise from genetic isolation, and/or small population sizes.

This study evaluates the use of commercially available instruments for locating and collecting accelerants in the field. Electronic noses can be used to scan a fire scene for the possible presence of an accelerant. The TLV Sniffer® was found to be able to detect accelerants at low levels but did alert to some burned matrix alone. When subjected to a proficiency test designed for canines, the TLV Sniffer® was able to locate accelerants in two of the three tests. The tpi®Pocket was found not to be sensitive or selective enough to be useful in locating accelerants. Once the location of possible accelerants has been determined, they can be collected by dynamic headspace sampling in the field with the Portable Arson Sampler (PAS). The PAS was found to be able to collect a broad range of compounds from ignitable liquids and had comparable efficiency to a conventional method.

In this project the selective conversion of glucose to ethanol from glucose/fructose mixtures was investigated. The process was carried out using a mutant of Saccharomyces cerevisiae, batchwise, continuously with immobilized cells and semicontinuously. The kinetic behaviour of S. cerevisiae ATCC 36859 was studied using batch fermentation data. The growth of the yeast is inhibited equally by glucose and fructose, even though fructose is not consumed by the yeast. Fermentation models were formulated in this work. These models include terms which account for the inhibition of growth, glucose consumption and ethanol production by the carbohydrate and ethanol. The models predict that the growth rate of the yeast will be zero if the medium contains either 488 g/L total carbohydrates of 62 g/L ethanol. Batch tests were carried out with hydrolyzed Jerusalem artichoke juice and High Fructose Corn Syrup. An ethanol productivity of 21 g/Lh was attained in a batch process using an initial biomass concentration of 94 g/L. It was found though that this process suffered from the inhibitory effects of high total carbohydrate concentrations, therefore products containing high fructose concentrations were produced with lower ethanol productivities. In addition, reuse of the biomass resulted in a reduction of 40% in its activity. The cells were immobilized in calcium alginate beads and placed in a tubular reactor. In this form they were used for more than 1000 hours without a loss of activity. A syrup containing fructose as 99% of the reducing sugars was produced from synthetic as well as from food grade glucose/fructose mixtures. A maximum ethanol productivity of 13 g/Lh was attained. A product containing 76 g/L ethanol was also produced in this process. The productivity of the reactor was reduced as the total carbohydrate concentration was increased, therefore products with a high fructose concentration ($>$150 g/L) could not be formed without a significant drop in the productivity using the immobilized cells. The inhibitory effects of high total carbohydrate concentrations were reduced by using a fed batch process. In this scheme, 42 High Fructose Corn Syrup was used with and without added nutrients as the feed solution; sterilization of the syrup was not necessary due to its high solids concentration. The syrup was continuously fed to a bioreactor, the glucose was converted to ethanol while the fructose accumulated. A syrup containing 257 g/L fructose and 68 g/L ethanol was produced in this process. The product formed in the process was purified with activated carbon and ion-exchange resin. A clear and colourless fructose syrup that visibly resembled HFCS was produced. The ethanol in the product allowed for storage of the product for long periods of time before its further treatment. (Abstract shortened by UMI.)

In this study, a mutant of the yeast Saccharomyces cerevisiae was used for the selective conversion of glucose to ethanol using feed solutions of sucrose. Batch fermentation using 30% (w/v) sucrose without membrane separation of ethanol required about 27 hours for glucose to be decreased to 2% (w/v), with a fructose yield of 99%, and an ethanol yield of 78%. Batch fermentation using 30% (w/v) sucrose with membrane separation of ethanol required about 16.5 hours for glucose to be decreased to 2% (w/v), with a fructose yield of 96.5% and an ethanol yield of 79.5%, if the membrane was started after 6 hours of batch mode. The process required about 15 hours if the membrane was started after 3 hours of batch mode, with a fructose yield of 92%, and an ethanol yield of 82%. In fed-batch mode the yeast was able to process the equivalent of a 40% (w/v) sucrose feed in 24 hours, compared to well over 40 hours without ethanol removal, with yields of, 98% fructose, and 82% ethanol. (Abstract shortened by UMI.)

This research project was focused on the development of a novel enzymatic method for upgrading commercial canola meal by decreasing its phenolic content. The new method is based on the enzymatic transformations of sinapic acid esters (SAE) and free sinapic acid (SA), the two main constituents of the phenolic fraction of canola meal (CM), using an enzyme preparation secreted by the white-rot fungi Trametes versicolor ATCC 42530. The study was divided into three parts: (1) enzyme production; (2) characterization of the enzyme produced--a model enzymatic system; (3) enzymatic upgrading of commercial canola meal--a canola meal system. The enzyme preparation produced was characterized in the model enzymatic system using sinapic acid (SA), sinapine (SIN) and sinapaldehyde (SALD). The results showed that the enzyme is inhibited by high concentrations of SIN and SA. Depending on the substrate, the optima temperatures and pH are in the range of 50$\sp\circ$C-60$\sp\circ$C and 3.3-4.5, respectively. The enzyme was very thermostable; the maximum thermal stability was noticed at pH values between 4.5 and 6.5. Sodium azide was a strong inhibitor of this enzyme while its activity was not affected by EDTA. Based upon the results obtained, the enzyme was characterized as a polyphenol oxidase. The overall transformation of SA was described by a mathematical model based on the Theorell-Chance Bi-Bi mechanism with oxygen as the first substrate, and the second substrate being one of the alternate phenolic compounds: SA, DAD and the unknown compound formed via the thermolysis of DAD. The modeling of sinapine transformation was also considered in this work. A mechanistic model, based on the Theorell-Chance Bi-Bi mechanism, that simultaneously predicted the effects of the concentrations of the enzyme, SIN and oxygen, for any given pH and temperature level, on the rates of the enzymatic reaction was formulated. The model parameters were estimated following the new procedure developed in this work for analyzing data concerning the effects of pH and temperature on enzyme activity. The formula relating the optimum pH of the reaction with the temperature was proposed. The enzyme preparation produced and subsequently characterized was used in the novel method to decrease the phenolic content in commercial CM, which was based on the addition of the enzyme to the meal-buffer slurry. It was found that: (1) the natural buffering capacity of CM resulted in the negligible effect of the pH of the buffer, which was used as the continuous phase in the process, on the extent of SAE decrease; (2) the system was saturated with the enzyme when the enzyme concentration was 4 nkat per mL of the continuous phase; (3) the optimum temperature was 50$\sp\circ$C. (Abstract shortened by UMI.)

No description available.

No description available.