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We present an investigation of the ultraviolet and X-ray spectra of the Seyfert 1.5 galaxy Markarian 817. The ultraviolet analysis includes two recent observations taken with the Cosmic Origins Spectrograph (COS) in 2009 August and December, as well as archival spectra from the International Ultraviolet Explorer and the Hubble Space Telescope. Twelve Ly alpha absorption features are detected in the 1997 Goddard High Resolution Spectrograph (GHRS) and 2009 COS spectra-of these, four are associated with high-velocity clouds in the interstellar medium, four are at low significance, and the remaining four are intrinsic features, which vary between the GHRS and COS observations. The strongest intrinsic absorber in the 1997 spectrum has a systemic velocity of similar to-4250 km s(-1). The corresponding feature in the COS data is five times weaker than the GHRS absorber. The three additional weak (equivalent width from 13 to 54 m angstrom) intrinsic Lya absorbers are at systemic velocities of -4100 km s(-1), -3550 km s(-1), and -2600 km s(-1). However, intrinsic absorption troughs from highly ionized Civ and N v are not detected in the COS observations. No ionized absorption signatures are detected in the similar to 14 ks XMM-Newton EPIC spectra. The factor of five change in the intrinsic Lya absorber is most likely due to bulk motions in the absorber, since there is no drastic change in the UV luminosity of the source from the GHRS to the COS observations. In a study of the variability of Mrk 817, we find that the X-ray luminosity varies by a factor of similar to 40 over 20 years, while the UV continuum/emission lines vary by at most a factor of similar to 2.3 over 30 years. The variability of the X-ray luminosity is strongly correlated with the X-ray power-law index, but no correlation is found with the simultaneous optical/UV photometry.

This thesis studied the characteristics and applications of n-type silicon oxide (SiOx) produced through plasma enhanced chemical vapor deposition were studied through. n-type SiOx has shown excellent results in various applications of solar cell technology including back reflectors and intermediate reflecting layers. These results can aid in making amorphous silicon cells thinner. Thinner cells are not only cheaper and less resource intensive but are known to be much less susceptible to degradation, which is a major research goal in amorphous silicon solar cells. This thesis used three experiments to characterize and utilize n-type SiOx. First, the effects of varying deposition parameters of SiOx films were analyzed. SiOx layers were then applied as back reflectors of p-i-n amorphous silicon solar cells. Finally, SiOx was integrated into a two-period, one-dimensional photonic crystal. Forward power, pressure, CO2 flow and PH3 flow during deposition were varied to study their effects on SiOx films. Optical and electrical characteristics, as well as the deposition rate, of the films were measured as each deposition parameter was varied. Raman spectroscopy was also used to analyze the crystalline silicon structures in the material. These measurements showed that an increase in the oxygen content of SiOx enhanced its optical characteristics, while decreasing its electrical characteristics. CO2 flow as well as power and pressure had significant an impact on the oxygen content. Furthermore, it was found that increasing PH3/SiH4 flow ratio above 0.024 decreased the doping concentration of the SiOx film and had adverse effects on both the conductivity and activation energy of the films. Raman spectroscopy results suggested that the SiOx contained 5-7 nm crystalline silicon features. SiOx layers were deposited on amorphous silicon cells using both a p-i-n-SiOx configuration, as well as a p-i-SiOx configuration that contained no n-type amorphous silicon layer. In addition to, Sustainable Energy Technologies, Electrical Sustainable Energy, Electrical Engineering, Mathematics and Computer Science

Variable number of tandem repeats (VNTR) polymorphism in the interleukin 4 (IL-4) gene has been associated with end-stage renal disease (ESRD) subjects in many different populations, although with conflicting results. We determined the 70 bp of VNTR polymorphism at intron 3 of the IL-4 gene in Malaysian ESRD subjects. Buccal cells were collected from 160 case and 160 control subjects; genomic DNA was amplified using PCR, followed by agarose gel electrophoresis. There were significant differences in genotypes and alleles of the IL-4 gene. We conclude that VNTR polymorphism of the IL-4 gene is a risk factor for the development of ESRD among Malaysians.

The T344C polymorphism of aldosterone synthase CYP11B2 gene at promoter region was vastly studied in various populations with conflicting results in relation to End-stage Renal Disease (ESRD). In this study, researchers aimed to know the association of T344C polymorphism of CYP11B2 gene in Malaysian ESRD subjects. This study involved 165 Malaysian ESRD subjects and 165 healthy individuals as control subjects. Using commercially available kits, genomic DNA was extracted from the subjects using their buccal cells and the blood. The 152 bp product of CYP11B2 gene polymorphism were amplified by Polymerase Chain Reaction (PCR) and digested with Hae III restriction enzyme using Restriction Fragment Length Polymorphism (RFLP) method. The restricted fragments were separated by metaphor agarose gel electrophoresis and showed 152 bp represent TT allele (wild type), 152 and 97 bp represent the TC allele (heterozygous) and 97 and 56 bp represent CC allele (mutant type) as the genotypes for T344C polymorphism. The frequency of TT, TC and CC genotypes of T344C in CYP11B2 gene in ESRD subjects were 98 (59.39), 60 (36.36%) and 7 (4.24%) while 92 (55.76), 70 (42.42) and 3 (1.82%) were found in control subjects, respectively. The genotypic and allelic frequencies of T344C polymorphism of CYP11B2 gene show no significant differences as compared to control subjects (p>0.05). The T allele of T344C polymorphism of CYP11B2 gene might not be considered as a possible genetic marker or predisposing risk factor for ESRD in Malaysian subjects. However, this study has to be further continued with more subjects to confirm the association of CYP11B2 gene mutation with ESRD.

We present an investigation of the ultraviolet and X-ray spectra of the Seyfert 1.5 galaxy Markarian 817. The ultraviolet analysis includes two recent observations taken with the Cosmic Origins Spectrograph (COS) in 2009 August and December, as well as archival spectra from the International Ultraviolet Explorer and the Hubble Space Telescope. Twelve Ly alpha absorption features are detected in the 1997 Goddard High Resolution Spectrograph (GHRS) and 2009 COS spectra-of these, four are associated with high-velocity clouds in the interstellar medium, four are at low significance, and the remaining four are intrinsic features, which vary between the GHRS and COS observations. The strongest intrinsic absorber in the 1997 spectrum has a systemic velocity of similar to-4250 km s(-1). The corresponding feature in the COS data is five times weaker than the GHRS absorber. The three additional weak (equivalent width from 13 to 54 m angstrom) intrinsic Lya absorbers are at systemic velocities of -4100 km s(-1), -3550 km s(-1), and -2600 km s(-1). However, intrinsic absorption troughs from highly ionized Civ and N v are not detected in the COS observations. No ionized absorption signatures are detected in the similar to 14 ks XMM-Newton EPIC spectra. The factor of five change in the intrinsic Lya absorber is most likely due to bulk motions in the absorber, since there is no drastic change in the UV luminosity of the source from the GHRS to the COS observations. In a study of the variability of Mrk 817, we find that the X-ray luminosity varies by a factor of similar to 40 over 20 years, while the UV continuum/emission lines vary by at most a factor of similar to 2.3 over 30 years. The variability of the X-ray luminosity is strongly correlated with the X-ray power-law index, but no correlation is found with the simultaneous optical/UV photometry.

The purpose of this study is to determine the technical and economic feasibility of a smallscale bioreactor called the Methanizer for a restaurant. The bioreactor converts organic waste produced by the restaurant into methane. This methane can be used to power the restaurant’s cooking stoves. The system proposed is a double-tank, batch-fed bioreactor. This product will help reduce the need for natural gas as well as cut down on landfill use. Results from the technical analysis showed that the product would take 6 m3 of space, but is capable of saving a natural gas equivalent of 735 m3/year and 1470 m3/year for a small and medium sized restaurant, respectively. Economic analysis showed that the product is not economically viable for a small-scale restaurants but increased gas prices, subsidies, payment plans and scaling up to larger restaurants would make the Methanizer marketable. Producing a marketable Methanizer is estimated to take around four years and would therefore be possible in 2013.

Several genome-wide association studies were done extensively in many populations in finding the candidate genes predisposing to Type 2 Diabetes Mellitus (T2DM). In that way, Transcription Factor 7-Like 2 (TCF7L2) and Ectoenzyme Nucleotide Pyrophosphate Phosphodiesterase 1 (ENPP1) genetic variants were found to be associated with increased risk of T2DM in various populations. In this cross-sectional study, rs7903146 (C/T) polymorphism of TCF7L2 gene and K121Q polymorphism of ENPP1 gene was analyzed in T2DM with or without hypertension in Malaysian subjects. A total of 165 samples consisting of 50 T2DM without hypertension, 55 T2DM with hypertension and 60 healthy individuals were recruited for this study. Genomic DNA was amplified to determine the genotypes of rs7903146 (C/T) and K121Q polymorphisms using hot start PCR followed by RFLP method. The mean age for patient and control subjects was 57.26±10.02 and 45.65±10.93 years, respectively. There was no significant differences (p>0.05) found in genotype and allele frequency for both rs7903146 (C/T) and K121Q polymorphism of TCF7L2 and ENPP1 gene, respectively. This preliminary results show that both polymorphisms was not an independent risk factor to T2DM with or without hypertension in Malaysian subjects. However, replication studies in this population with larger sample size was strongly recommended.

Genetic Polymorphisms are the variations found in the DNA sequences and they are integral to the development of genetic markers to identify individuals at risk. The genotypic distribution of various genetic polymorphisms involved in essential hypertension (EHT) and type 2 diabetes mellitus subjects (T2DM) has been established in many populations with conflicting results but in Malaysian subjects it has not been well characterized. The main objective of this study was to determine the association of various polymorphisms involved in the renin angiotensinaldosterone system (RAAS), insulin receptor, lipoprotein lipase, interleukin gene and G protein ß 3 subunit genes in EHT and T2DM of Malaysian subjects. This crosssectional study includes 70 EHT without T2DM, 60 T2DM, 65 EHT with T2DM and 75 unrelated healthy control subjects. Genomic DNA was extracted from the peripheral blood and the plasma was separated and analyzed for the biochemical analyses. The genotypes of the various genetic polymorphisms were determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), mutagenically PCR and the hot-start PCR methods. All PCR products and the restricted fragments were resolved electrophoretically on agarose and polyacrylamide gels. Statistical analyses was done using SPPS version 14.0. The baseline characteristics such as age, body mass index, diastolic blood pressure, fasting plasma glucose, high density lipoprotein cholesterol and sodium differed significantly (p<0.05) in case subjects compared to control subjects but not in low density lipoprotein cholesterol, total cholesterol and potassium. The insertion/deletion (I/D) and G2350A polymorphism of the angiotensin converting enzyme (ACE) gene and the I/D polymorphism of the alpha adrenoceptor gene differed significantly in EHT and T2DM subjects, whereas the A6G variant of the angiotensinogen (AGT) gene differed significantly (p<0.05) in the EHT and EHT+T2DM subjects when compared to t

The presence of a dimorphic BglI site in the first intron of the Renin (REN) gene is an increased risk in essential hypertension. Several studies have found the association between BglI dimorphism and essential hypertension with conflicting results in various populations, which might be due to ethnic and geographical variations. The objective of this study is to determine the relationship between the BglI dimorphism of REN gene and Essential Hypertension (EHT) with or without Type 2 Diabetes Mellitus (T2DM) in Malaysian subjects. The study includes 70 EHT, 60 EHT with T2DM and 70 unrelated healthy subjects from the three ethnic groups of Malaysian Subjects. The genotype of BglI dimorphism was done by PCR-RFLP method using BglI restriction enzyme. The frequency of the BglI (+) allele was 37.86% in EHT, 40.83% in EHT with T2DM subjects and 35.71% in control subjects. The results of this study indicate that the BglI (+) allele of REN gene is not associated with essential hypertension with or without T2DM in Malaysian Subjects.