New Heterocyclic Syntheses from Pyridinethiones: an Efficient Route for the Syntheses of Some Novel Azo Derivatives of Thieno[2,3-b]pyridine as Potential Anti-bacterial and Anti-cancer Agents

Derivatives of a heterocyclic system 3-(pyrrol-1-yl)thieno[2,3-b]pyridine 5 and 6 carrying various substituents in the position 2 were synthesized. Some of these products were used to build up a variety of nitrogen- and/or oxygen-containing heterocyclic rings in that position. The electronic configurations of selected products were investigated using the AM1 semi-emperical molecular orbital method. Considerable variations in the magnitude and oriention of the dipole moment were observed. Further, the relative stability of the structures was investigated at physiological conditions via calculation of the electrostaticcomponent of the solvation free energy. The synthesized series showed favourable solvation free energies which were within the range from –30 to –23 kcal/mol.The high polarity and favourable solvation free energychanges at physiological conditions suggest that substitutionin the position 2 could enhance the biological activity of the 3-(pyrrol-1-yl)thieno[2,3-b]pyridine derivatives

Asphaltene stability in crude oil during carbon dioxide injection and its impact on oil recovery: A review, data analysis, and experimental study

Crude oils are usually associated with many compounds, some of which are favorable and others, which are not. One of the most unfavorable components of crude oil that pose severe operational problems and decreases oil production significantly are asphaltenes. These compounds are solids that are homogenized in the crude oil at room temperature but tend to separate from solution when agitated. They can deposit in the reservoir pores, wellbore, and transportation pipelines thus causing severe operational problems and oil recovery reduction. Even though researchers have been studying asphaltenes for more than 100 years, there is still an ambiguity concerning asphaltene structure and characteristics since asphaltenes have no unique structure. This research performed a comprehensive data analysis on both laboratory studies and field cases involving asphaltene in order to provide a generalized guideline on asphaltene properties asphaltene stability. The analysis was based on more than 200 references involving more than 4000 experiments and 19 field studies. Two statistical analysis tools were used, including histograms and boxplots. After determining the factor impacting asphaltene, this research conducted experiments to understand the impact of these factors on asphaltene stability in crude oil during carbon dioxide (CO2) injection in unconventional shale nanopores, since very limited research has been conducted in this area. The research investigated the impact of several factors including pressure, temperature, oil viscosity, pore size, porous media thickness, and heterogeneity on asphaltene precipitation, pore plugging, and oil recovery reduction. A Pareto Plot was also generated to determine the factor that had the strongest impact on asphaltene instability in the crude oil --Abstract, page iv

Effect of Short-Term High Fat Diet Inducing Obesity on Hematological, Some Biochemical Parameters and Testicular Oxidative Stress in Male Rats

Obesity constitutes a health problem due to its increasing worldwide prevalence. Among the health detriments caused by obesity, reproduction is disrupted. Some studies have shown a relationship between obesity and infertility, but until now it remains controversial. The objective of the current work was to examine the effect of diet-induced obesity on blood parameters, liver and kidney function tests, lipid profile and testicular oxidative stress. For that purpose, Male rats were fed ad libitum with a standard diet (control group; n.= 15) and high fat diet (HFD group; n.= 15) for 6 weeks. Hematological parameters, urea, creatinine, albumin were similar between the two groups. Intergroup testosterone levels were also comparable. The high fat diet induced significant increase in serum triglycerides, cholesterol, low density lipoprotein and very low density lipoprotein cholesterol concentrations. This diet also increases significantly alanine aminotransferase and aspartate aminotransferase activities and decreased total protein level and high-density lipoprotein cholesterol concentration. Furthermore, HFD showed a significant increasing in malondialdehyde contents in testes and decreasing in superoxide dismutase activity, the results of this study concluded that short-term high fat diet affect on liver enzymes and causing oxidative stress in testes

Effect of Unfolding on the Spectral Statistics of Adjacency Matrices of Complex Networks

Random matrix theory is finding an increasing number of applications in the context of information theory and communication systems, especially in studying the properties of complex networks. Such properties include short-term and long-term correlation. We study the spectral fluctuations of the adjacency of networks using random-matrix theory. We consider the influence of the spectral unfolding, which is a necessary procedure to remove the secular properties of the spectrum, on different spectral statistics. We find that, while the spacing distribution of the eigenvalues shows little sensitivity to the unfolding method used, the spectral rigidity has greater sensitivity to unfolding.Comment: Complex Adaptive Systems Conference 201

Analysis of the subthreshold CMOS logic inverter

AbstractThere is no doubt that operating the MOSFET transistor in the subthreshold region, where the power-supply voltage is less than the threshold voltage, has an increasing importance due to the reduced power consumption. In this paper, the analysis of the CMOS logic inverter in the subthreshold region is addressed quantitatively with the static and dynamic characteristics investigated and compared with that operating in the superthreshold region. Specifically, compact-form equations are derived for the output-low voltage, output-high voltage, maximum-input voltage at logic “0,” minimum-input voltage at logic “1,” and threshold voltage of the inverter. Also, the static-power consumption and dynamic-power consumption are investigated and equations are derived for them. Compact-form expressions are derived for the low-to-high and the high-to-low propagation delays along with the fan-out. Qualitative discussions are also provided. The results of the quantitative analysis are verified by comparison with the simulation results adopting the 65nm CMOS technology