Supersonic laminar-flow control

Detailed, up to date systems studies of the application of laminar flow control (LFC) to various supersonic missions and/or vehicles, both civilian and military, are not yet available. However, various first order looks at the benefits are summarized. The bottom line is that laminar flow control may allow development of a viable second generation SST. This follows from a combination of reduced fuel, structure, and insulation weight permitting operation at higher altitudes, thereby lowering sonic boom along with improving performance. The long stage lengths associated with the emerging economic importance of the Pacific Basin are creating a serious and renewed requirement for such a vehicle. Supersonic LFC techniques are discussed

Progress in Polyhaploid Production Techniques of Hexaploid Wheat through Wide Crosses

(Triticum aestivum L.) through wide crosses were evaluated in terms of pollen sources, 2,4-D application, embryo rescue and chromosome retention. Pollen sources included Hordeum bulbosum L., Zea mays L., Pennisetum glaucum (L.) R. Br., Sorghum bicolor (L.) Moench, and Tripsacum dactyloides (L.) L. Maize-mediated polyhaploid production was more stable than the other methods because of a lesser genotypic influence on embryo formation. Application of 2,4-D onto wheat after pollination was critical to promote seed setting and embryo formation in all cross combinations. Embryo rescue was necessary at an appropriate embryo developmental stage to obtain plant regeneration. Paternal chromosomes were eliminated by the stage of active growth of the polyhaploid seedlings. Polyhaploid production frequencies ranged between 10 and 20% of pollinated wheat florets, suggesting germ plasm genotypic effects

Determination of resistance pattern of bacteriostatic antimicrobial drugs by analysis of blood culture reports

Background: Determination of each isolated bacterium from blood culture and pattern of antimicrobial sensitivity has an important role epidemiologically in a region and can assist physicians in the determination of primary antimicrobial agents. In this study, schema of resistance of bacteriostatic antimicrobials in blood culture is evaluated. Determination of resistance pattern of bacteriostatic antimicrobial drugs by analysis of blood culture report.Methods: A retrospective analysis of microbiological blood culture and antibiotics sensitivity results have been done. A total of 120 laboratory culture results were selected randomly during the observational period. These all-blood culture reports were analyzed for bacteriostatic antimicrobial resistance pattern.Results: The 41 bacterial isolates were obtained from 120 blood culture reports, 24.39% (10) were gram positive and 75.60% (31) were gram-negative. The most frequently isolated gram-negative organisms were K. pneumoniae (34.14%) followed by Pseudomonas (12.19%), E. coli (12.19%). The most frequently isolated gram-positive organism was staphylococcus aureus. All isolates showed less resistance to bacteriostatic antibiotics like clindamycin, chloramphenicol, co-trimoxazole, doxycycline, linezolid, tetracycline, nitrofurantoin, erythromycin, tigecycline.Conclusions: S. aureus, E. coli and Klebsiella spp. pseudomonas aeruginosa were the leading causes of septicaemia or any type of infection in our study finding. These bacteria isolates were highly resistant to bactericidal antimicrobials. But bacteriostatic antimicrobial has shown less resistance compared to bactericidal

Development of Quality Standards of Aegle marmelos L. Leaves

Aegle marmelos L (Rutaceae) is a moderately size deciduous tree, growing wild throughout the deciduous forest of India. It is commonly used in day to day life. In present investigation an attempt has been made for the pharmacognostical standardization and evaluation of Aegle marmelos leaves. The pharmacognostical evaluation comprises of detailed macroscopy, powdered microscopy, fluorescence analysis, quantitative microscopy and physical constants such as ash and extractive values. The leaves extracts were subjected to preliminary phytochemical screening. The data obtained in present study will serve as valuable tool for identification, authentication and detection of adulterants, standardization and quality control of the drug. The developed technique will also be useful for the standardization of formulations containing A. marmelos.ÂÂ

Molecular analysis of genetic diversity in elite II synthetic hexaploid wheat screened against Barley yellow dwarf virus

The presence of sufficient genetic diversity in the germplam is an important prerequisite for the improve-ment and efficient use of available material. Traditionally, the data on agronomic, morphological and physiological plants traits are used to estimate the genetic diversity. But now molecular markers are available for authenticated and reliable studies for genetic diversity. The present study was conducted to assess the genetic diversity of Elite-II synthetic hexaploid (SH) wheat by genome DNA fingerprinting as revealed by random amplified polymorphic DNA (RAPD) analysis. Ten decamer RAPD primers (OPG-1, OPG-2, OPG-3, OPG-4, OPG-5, OPA-3, OPA-4, OPA-5, OPA-8, and OPA-15) were used to evaluate the diversity profile of the selected SH entries. Primers OPG-2 andOPA-4 gave the highly polymorphic results. The pair wise similarity values shows that genotypes 1, 20 and 30 have most closest relationship with highest similarity values i.e., 100% while genotypes 9and 13 show dictinct relationship with minimum similarity value that is, 54%. Therefore, the allelic variation of the SH resistance germplasm is a potent means to enrich and improve bread wheat cultivars where BYDV is a production threat and these can be used in future wheat breeding programme

Linear and nonlinear PSE for compressible boundary layers

Compressible stability of growing boundary layers is studied by numerically solving the partial differential equations under a parabolizing approximation. The resulting parabolized stability equations (PSE) account for nonparallel as well as nonlinear effects. Evolution of disturbances in compressible flat-plate boundary layers are studied for freestream Mach numbers ranging from 0 to 4.5. Results indicate that the effect of boundary-layer growth is important for linear disturbances. Nonlinear calculations are performed for various Mach numbers. Two-dimensional nonlinear results using the PSE approach agree well with those from direct numerical simulations using the full Navier-Stokes equations while the required computational time is less by an order of magnitude. Spatial simulation using PSE were carried out for both the fundamental and subharmonic type breakdown for a Mach 1.6 boundary layer. The promising results obtained show that the PSE method is a powerful tool for studying boundary-layer instabilities and for predicting transition over a wide range of Mach numbers

Computational Analysis of the G-III Laminar Flow Glove

Under NASA's Environmentally Responsible Aviation Project, flight experiments are planned with the primary objective of demonstrating the Discrete Roughness Elements (DRE) technology for passive laminar flow control at chord Reynolds numbers relevant to transport aircraft. In this paper, we present a preliminary computational assessment of the Gulfstream-III (G-III) aircraft wing-glove designed to attain natural laminar flow for the leading-edge sweep angle of 34.6deg. Analysis for a flight Mach number of 0.75 shows that it should be possible to achieve natural laminar flow for twice the transition Reynolds number ever achieved at this sweep angle. However, the wing-glove needs to be redesigned to effectively demonstrate passive laminar flow control using DREs. As a by-product of the computational assessment, effect of surface curvature on stationary crossflow disturbances is found to be strongly stabilizing for the current design, and it is suggested that convex surface curvature could be used as a control parameter for natural laminar flow design, provided transition occurs via stationary crossflow disturbances

CFD Vision 2030 and its Implementation

No abstract availabl