Mohamed A. Elsayed

Accuracy of B-mode ultrasonography for diagnosing pregnancy and determination of fetal numbers in different breeds of goats

A total of 150 does of different breeds were used to evaluate the accuracy of transrectal (TRU) and transabdominal ultrasonography (TAU) for pregnancy diagnosis and fetal number estimation and to study the effect of breed and age of goats on the accuracy of ultrasonography. All does were scanned by TRU at days 17-22, 24-29 and 31-36 and by TAU at days 39-44 and 46-51 after breeding. The sensitivity (Se) of TRU for detecting pregnant does increased significantly (81.6% vs. 97.7%; P<0.0005) from days 17-22 to 24-29. There was a significant (P<0.05) effect of breed of goats on the specificity (Sp) of TAU for diagnosing non-pregnancy between days 39 and 51. In addition, there was a significant (P<0.01) effect of breed of goats on the Se and Sp of TRU for determination of does carrying multiples and singles, respectively, between days 24 and 36. The sensitivity of TAU for diagnosing pregnant does tended to be significantly (P=0.06) higher in young does (1.5-2 yr) than in older does (>2-9 yr) at days 39-44. The accuracy of TRU for determination of does carrying singles was significantly (P<0.05) higher in young does than that in older ones at days 24-29. In conclusions, TRU could be accurately used for early pregnancy diagnosis and fetal number estimation at days 24-29 and days 31-36, respectively, with accuracy similar to that of TAU at days 39-51. Furthermore, breed and age of does might influence the accuracy of ultrasonography for pregnancy diagnosis and fetal numbers estimation.

A Fast Quadratic Programming Approach for Large-Scale Reactive Power Optimization

ABSTRACT A fast reactive power optimization method for large-scale power systems has been developed in this paper. The method is fast and robust. The large-scale power system is decomposed into subsystems. The subsystem solution is non-iterative and it provides a suboptimal solution when constraints are violated. Results of applying this method to the IEEE 118 bus system and a sample 200 bus system indicate it can be used in real-time power system control.

Synthesis, Anticancer Screening and Molecular Docking Studies of New Heterocycles with Trimethoxyphenyl Scaffold as Combretastatin Analogues.

BACKGROUND In this study, synthesis, molecular docking and anticancer screening of new series of substituted heterocycles with trimethoxy phenyl scaffold as Combretastatin analogues were described. Substituted pyridines were synthesized via the reaction of (E)-3-(dimethylamino)-1-(3,4,5- trimethoxyphenyl)prop-2-en-1-one (2) with active methylene reagents. Substituted pyrimidines were prepared by the reaction of the enaminone (2) with heterocyclic amines and 6-amino thiouracil. Furthermore, a series of pyrazoles substituted with trimethoxyphenyl scaffold were prepared by the reaction of the enaminone 2, with selected examples of hydrazonoyl halides. CONCLUSION The cytotoxic effect of the newly compounds was evaluated against HePG-2, HCT-116, MCF-7 and PC3 cancer cell lines. Among the new products, compounds 2, 3, 7 and 10 were found to exhibit promising results as anticancer agents. The IC50 values of 2, 3 and 7 were 54.6, 77.4 and 47.4 on PC3 respectively. Also, compound 2 had IC50 28.06 on MCF7. Moreover, the selectivity index indicated that compounds 2 and 3 are safe.

MID-TERM DYNAMIC RESPONSE OF ISOLATED POWER SYSTEMS TO GENERATION OUTAGES

ABSTRACT This paper presents a comprehensive power system model to study the mid-term dynamic response of isolated power systems to large disturbances such as generating unit outages. The interaction of the system with its individual components such as prime-mover and generator including their controllers, frequency and voltage dependency of system loads as well as the transmission network is considered in the described model. This model has been applied on the regional power system in Qatar, where a digital package based on the Advanced Continuous Simulation Language (ACSL) is developed to determine the system response during emergency period after generation outages. The simulation results are used to discuss the following problems: – How does the generation outage affect the frequency behaviour and power exchange between different network parts? – How will the voltage level change after such generation deficiency? – Where and when do the system under-frequencies appear, which exceed protection limitati...