2,097 research outputs found
Technologically important properties of lactic acid bacteria isolated from raw milk of three breeds of Algerian dromedary (Camelus dromedarius)
A total of 9 samples of individual dromedary raw milks from N’ajjer (3), Targui (3) and Reguibi (3) breeds were collected from 3 camels nomad herd in south Algeria and were analysed for bacterial load. A totalof 23 strains of lactic acid bacteria were isolated, out of which 12 strains were cocci and 11 strains were facultatively heterofermentative lactobacilli. Lactic acid bacteria were identified on the basis ofphenotypic characters as Lactococcus lactis subsp. lactis, Enterococcus faecalis, Enterococcus faecium, Enterococcus durans, Lactobacillus paracasei subsp. paracasei, Lactobacillus plantarum andLactobacillus rhamnosus. Whole cells of lactococci, enterococci and lactobacilli showed proteolytic activity and were found to differed in terms of their acidifying activities. Proteolytic and autolyticactivity were generally higher for most lactobacilli compared to other isolates and none of the strains produced biogenic amines in the method applied. A wide variety of this 23 lactic acid bacteria strainsisolated from Algerian dromedary milks that showed potentially important properties suggest that they are good candidate for camels milk processing or other dairy fermentation process
Bacteriocinogenic potential and genotypic characterization of three Enterococcus faecium isolates from Algerian raw milk and traditional butter
The detection of bacteriocinogenic potential of Enterococcus sp. isolates from Algerian raw milk coded LO4 and LO12 and from traditional butter coded BRO2 was carried on M17 buffered medium. PCR amplification of Enterococcus sp. DNA using specific enterococcal primers gave 733 bp fragments. The phylogenetic analysis using the neighbour joining method further supported the identification of the three strains as Enterococcus faecium. These bacteria were bacteriocinogenic against Pseudomonas sp, Proteus mirabilis and E. faecium. Lyophilisate extracts were tested for sensitivity to enzymes, heating and effect of pH. Complete inactivation in bacteriocinogenic activity was observed after treatment with proteolytic enzymes. The antibacterial activity from E faecium LO12 was stable (1280 AU/ml) for range pH 2 to 12. Maximal activity from BRO2 strain was at pH 7 (20480 AU/ml) and from LO4 strain was at pH 7 and 6 (2560 AU/ml). Antibacterial activities of E. faecium BRO2 (5120 AU/ml) and E. faecium LO12 (640 AU/ml) remained stable at 60°C for 30 min. The antibacterial activity of .E faecium LO4 was stable at 100°C for 30 min (5120 AU/ml)
Use of Contingent Valuation Analysis in a Developing Country: Market Perceptions of Contamination on Johannesburg’s Mine Dumps
This study reports the results of a contingent valuation (CV) survey that was carried out in Johannesburg, South Africa. Students at Wits University conducted more than 300 face-to-face interviews with Africans living and/or working in Soweto, an African township located on the outskirts of Johannesburg, and nearby areas. The questions they asked were designed to determine the perceptions of risk regarding airborne mine dust and radon, a naturally occurring gas, and the effect that these perceptions had on the valuation of residential properties impacted by these substances. A probit model was used to evaluate the determinants of bidder behavior, using respondent demographics and other characteristics as independent variables. Residential property discounts for potentially contaminated housing sites by marginal bidders at the top of the market varied from -24% to -50%. Research issues in developing countries were addressed. Contingent valuation results in South Africa were compared to published results in the United States.
DESIGN OF MODIFIED SECOND ORDER SLIDING MODE CONTROLLER BASED ON ST ALGORITHM FOR BLOOD GLUCOSE REGULATION SYSTEMS
The type1 of diabetes is a chronic situation characterized by abnormally high glucose levels in the blood. Persons with diabetes characterized by no insulin secretion in the pancreas (ß-cell) which also known as insulin-dependent diabetic Mellitus (IDDM). In order to keep the levels of glucose in blood near the normal ranges (70-110mg/dl), the diabetic patients needed to inject by external insulin from time to time. In this paper, a Modified Second Order Sliding Mode Controller (MSOSMC) has been developed to control the concentration of blood glucose levels under a disturbing meal. The parameters of the suggested design controller are optimized by using chaotic particle swarm optimization(CPSO) technique, the model which is used to represent the artificial pancreas is a minimal model for Bergman. The simulation was performed on a MATLAB/ SIMULINK to verify the performance of the suggested controller. The results showed the effectiveness of the proposed MSOSMC in controlling the behavior of glucose deviation to a sudden rise in blood glucose
Caracterização fitossociológica do impacto de Pittosporum undutalum VENT. em três Fragmentos de floresta estacional semidecidual (FESD) na encosta da serra do Sudeste, Pelotas, RS.
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Synthesis and Characterization of New Derivatives of Thiazole with Liquid Crystalline properties
A new two series of liquid crystalline Schiff bases containing thiazole moiety with different length of alkoxy spacer were synthesized, and the relation between the spacer length and the liquid crystalline behavior was investigated. The molecular structures of these compounds were performed by elemental analysis and FTIR, 1HNMR spectroscopy. The liquid crystalline properties were examined by hot stage optical polarizing microscopy (OPM) and differential scanning calorimetry (DSC). All compouns of the two series display liquid crystalline nematic mesophase. The liquid crystalline behaviour has been analyzed in terms of structural property relationship. Keywords: Thiazole, Liquid crystal, Heterocyclic, Schiff bas
IMPLEMENTATION OF NEURAL - CRYPTOGRAPHIC SYSTEM USING FPGA
Modern cryptography techniques are virtually unbreakable. As the Internet and other forms of electronic communication become more prevalent, electronic security is becoming increasingly important. Cryptography is used to protect e-mail messages, credit card information, and corporate data. The design of the cryptography system is a conventional cryptography that uses one key for encryption and decryption process. The chosen cryptography algorithm is stream cipher algorithm that encrypt one bit at a time. The central problem in the stream-cipher cryptography is the difficulty of generating a long unpredictable sequence of binary signals from short and random key. Pseudo random number generators (PRNG) have been widely used to construct this key sequence. The pseudo random number generator was designed using the Artificial Neural Networks (ANN). The Artificial Neural Networks (ANN) providing the required nonlinearity properties that increases the randomness statistical properties of the pseudo random generator. The learning algorithm of this neural network is backpropagation learning algorithm. The learning process was done by software program in Matlab (software implementation) to get the efficient weights. Then, the learned neural network was implemented using field programmable gate array (FPGA)
Psychometric properties of the king spiritual intelligence questionnaire (KSIQ) in physical veterans of Iran-Iraq warfare
Aims: The study's purpose was to determine reliability and validity of the King spiritual intelligence questionnaires in veterans of Iran-Iraq Warfare. Methods: In this cross sectional study, 300 veterans of the Iran-Iraq war completed the King spiritual intelligence questionnaires. Principal components analysis (PCA) with varimax rotation was used to assess domain structure of the King spiritual intelligence questionnaires. Internal and external consistency reliability was assessed with Cronbach's alpha and intra-class correlation coefficient (ICC). Results: Internal consistency of King spiritual intelligence questions estimated with Cronbach's alpha, 0.872 and intra-class correlation coefficient (ICC).872 (CI 95%: 0.84 -0.89). The construct validity of the questionnaire was calculated using exploratory factor analysis that showed 3 factors with Eigen values of greater than one, which explained in total 44.7% of the variance. (1, 8 items, α= 0.87; 2, 5. items; α = 0.89; 3, 2 items, α= 0.51). Conclusion: The Persian version of King spiritual intelligence questionnaire demonstrated suitable validity and reliability among the Veterans of Iran-Iraq Warfare. With the consideration of the proper psychometric characteristics, this questionnaire can be used to further research spiritual intelligence in this population
CANCER GROWTH TREATMENT USING IMMUNE LINEAR QUADRATIC REGULATOR BASED ON CROW SEARCH OPTIMIZATION ALGORITHM
The rapid and uncontrollable cell division that spreads to surrounding tissues medically termed as malignant neoplasm, cancer is one of the most common diseases worldwide. The need for effective cancer treatment arises due to the increase in the number of cases and the anticipation of higher levels in the coming years. Oncolytic virotherapy is a promising technique that has shown encouraging results in several cases. Mathematical models of virotherapy have been widely developed, and one such model is the interaction between tumor cells and oncolytic virus. In this paper an artificially optimized Immune- Linear Quadratic Regulator (LQR) is introduced to improve the outcome of oncolytic virotherapy. The control strategy has been evaluated in silico on number of subjects. The crow search algorithm is used to tune immune and LQR parameters. The study is conducted on two subjects, S1 and S3, with LQR and Immune-LQR. The experimental results reveal a decrease in the number of tumor cells and remain in the treatment area from day ten onwards, this indicates the robustness of treatment strategies that can achieve tumor reduction regardless of the uncertainty in the biological parameters
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