Adama University

About: Adama University is a education organization based out in Nazrēt, Ethiopia. It is known for research contribution in the topics: Population & Adsorption. The organization has 840 authors who have published 1010 publications receiving 5547 citations. The organization is also known as: Adama Science and Technology University & ቴክኖሎጂ ዩኒቨርሲቲ, አዳማ ሳይንስና ቴክኖሎጂ ዩኒቨርሲቲ.

In vivo and In vitro Antioxidant Activities of Aqueous and Ethanol Stem Bark Extracts of Vitex doniana on Doxorubicin-induced Oxidative Stress in Rats

Abstract: Background: Oxidative stress is involved in the pathogenesis of hypertension, myocardial ischemia-reperfusion injury, atherosclerosis, muscular dystrophy, aging and other associated diseases. Vitex doniana is used in Adamawa, northern Nigeria to treat oxidative stress associated diseases. However, the antioxidative effects of the plant have not been scientifically examined in oxidative stress experimental animal models. The aim of this study is to investigate the in vitro and in vivo antioxidant activities of aqueous and ethanol stem bark extracts of Vitex doniana in Original Research Article Sulaiman et al.; AJRB, 8(2): 44-55, 2021; Article no.AJRB. 65898 45 oxidative stress model of rats. Methods: The study used 35 adult albino rats weighing 175 ± 25 g, of which 30 were induced with oxidative stress by intraperitoneal injection of doxorubicin (10 mg/kg) for three consecutive days. Animals were treated by oral administration of silymarin (100 mg/kg) and Vitex doniana aqueous or ethanol extract (100 mg/kg and 200 mg/kg) for 14 consecutive days before they were sacrificed on the 15th day and blood was analyzed for biochemical indices of oxidative stress. Results: The results of the phytochemistry showed the presence of alkaloids, tannins, flavonoids, steroids, phenols, saponins, terpenoids, glycosides: and total flavonoids (52.70 ± 1.60 mg/ml and 75.40 ± 0.80 mg/ml), total phenols (21.45 ± 1.54 mg/ml and 26.50 ± 1.22 mg/ml) for aqueous and ethanol stem bark extracts respectively. The extracts scavenged DPPH radical, reduced Fe 3+ and inhibited lipid peroxidation. Doxorubicin significantly (p<0.05) lowered the levels of SOD, CAT, GR and TAS and significantly (p<0.05) but, increased the level of LPO. Oral treatment with Vitex doniana extracts significantly (p<0.05) increased the activities of CAT, GR, SOD and TAS while LPO was significantly (p<0.05) lowered. Vitex doniana stem bark extracts significantly (p<0.05) improved the biochemical derangements observed in the induced untreated animals in comparable manner to that of Silymarin. Conclusion: The present study provides the scientific rationale for the use of Vitex doniana stem bark in traditional medicine and has a viable antioxidative capacity both in vitro and in vivo.

Detailed description of the transient effect of radiative carrier transition in the bulk of semiconductor: The case of gallium antimonide

Abstract: Upon solving the differential equation related to the rate of accumulation of photo-generated carriers in the respective bands of GaSb that involves radiative generation-recombination mechanisms under constant illumination in the entire bulk of the material, the transient response (time dependence) of the photo-generated carrier density and the excess carrier lifetimes during illumination and after switching-off illumination are described for a system under different injection levels. The rates of variations of the photo-generated carrier density and the radiative excess carrier lifetimes at the initial stages of the illumination and after switching-off the illumination are evaluated at different injection levels. The injection level dependences of the effective values of the photo-generated carrier density and the radiative excess carrier lifetimes are described. The competition of the thermal and the illumination effects in the band to band radiative recombination mechanism is also described thoroughly.

FPGA Implementation of Mac Based Stream Cipher-Phelix

Abstract: Now a day's many people are connected to the internet with large amount of confidential information such as mails, transactions, being transmitted every day. Privacy and the confidentiality of this information can be achieved by encryption algorithms. The consequence is the significant improvement of cryptanalysis techniques. Phelix is one of the high-speed stream encryption cipher technique with built-in single-pass functionality. In Phelix We use a 28-bit key, 27-bit nonce to create design strength of 128 bits. This paper simulates and implements the function of Phelix stream cipher, wrote the codes to implement full algorithm that includes encryption and decryption using Very high speed hardware description language (VHDL) and provided the simulation and implementation results using Active HDL Simulation tool and Xilinx implementation tool respectively. The simulation result shows that the designed IP core meets the required protocol specifications for the proper functioning of Phelix stream cipher.

Determination of caffeine content in Wollega Zones, Ethiopian coffee bean, pulp and leaves by high performance liquid chromatography

Abstract: Caffeine is a stimulant alkaloid found in aerial parts of many hot beverages, including coffee and tea. Due to its health impact, quantification of caffeine level in coffee is of paramount importance for consumers and traders, as well. Therefore, this study was designed to determine the caffeine content in coffee beverage prepared from coffee beans, pulp and leaves using high performance liquid chromatography coupled with a reverse phase C8 column and UV-detector. In this study, caffeine sample was extracted from coffee beans, pulp and leaves with boiled distilled water followed by solvent partition with chloroform. The extracted caffeine samples were analyzed alongside caffeine standard solutions over the concentration range of 5-25 μg/mL. For quantitative purposes, the standard caffeine gave an equation of Y=1270560x + 986903 (R2 = 0.998) and the retention time of 1.84 ± 0.01 min. In parallel to the standard caffeine solution, peak area of caffeine contents in 20 μL extracted caffeine samples of 2.5 g coffee powder in 100 mL of distilled water coffee beverage were registered. By using the peak area, caffeine concentration in injected sample and its concentration in the total sample solution was calculated. The percentage masses of caffeine (w/w%) in the original coffee samples were 1.30 ± 0.11% for beans, 0.90 ± 0.11% for pulp and 0.65 ± 0.10% for leaves. These results of caffeine contents in coffee beans in Wollega zone show high caffeine contents when compared with previously reported coffee beans (1.01 ± 0.04-1.19 ± 0.02%) of other parts of Ethiopia using UV/Vis. spectrophotometric technique.