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This paper examines the modifications in the flow and sound fields due to the application of a periodic suction-blowing excitation strip on the top and bottom surfaces of a NACA0012 airfoil. The flow and sound fields have been directly computed (D N S approach) by solving unsteady, two-dimensional compressible Navier–Stokes equations using physical dispersion relation preserving schemes. The flow approaches the airfoil at a Reynolds number of 5000 and 5 o angle of attack. In the no-excitation case, the sound is mainly created by the lift and drag dipole equivalent sources associated with vortex shedding. However, the application of suction-blowing excitation results in two additional sound sources: monopole-equivalent sound sources due to fluid movement in and out of the airfoil surface and the drag dipole-equivalent sound sources due to periodic change in the airfoil's effective cross-sectional area. The combined effects of these sound sources result in significant mitigation of sound on the suction side of the airfoil. The excitation amplitude and forcing frequency effects on sound field modifications have been studied in depth. Beats of sound have been observed when the forcing frequency is close to the excitation frequency. • Direct Numerical Simulation approach is used for Navier–Stokes equations. • Suction-blowing excitation induces monopole and drag dipole sound sources. • Excitation provided near the leading edge increases the lift-to-drag ratio. • Bias in sound directivity is observed for excitation near the trailing edge. • Sound beat is observed for frequencies close to vortex shedding frequency. [ABSTRACT FROM AUTHOR]

Our closest neighbor (Moon) is full of wonders and potentials that can help us learn more about the solar system and provide a habitat for space colonies. The lunar surface contains several potential volatiles implanted by the solar wind that can be used for In-Situ Resource Utilization (ISRU). Also by characterizing the lunar surface we can comprehend many solar system phenomenon. Radar has been proven to be very effective in characterizing and understanding the physical properties of the lunar surface. The success of Chandrayaan-2 (CH-2) in 2019 opened numerous doors to better understanding the lunar surface. The Dual Frequency Synthetic Aperture Radar (DFSAR), is the first L-band SAR ever used for lunar mapping. We approximated the dielectric values for the Permanently Shadowed Regions (PSRs) by combining the Integral Equation Model (IEM) and Artificial Neural Network (ANN). The two-dimensional Gaussian model proved to be more accurate when correlated with in-situ measurements made by the Apollo 17 mission out of four different configurations, but the validation process has its limitations, thus we analyzed the result from all the models. The real part of complex dielectric values of unknown craters near Malapert crater (PSRs SP 83260 0090770 and SP 841420 0059530) and Faustini crater (PSR SP 871460 0840750) were high in certain sections of the region and moderate in others. The high dielectric values of 11.2 and 10.9 were estimated by the two-dimensional Gaussian and Exponential model for the right-side walls of the PSRs SP 83260 0090770 and SP 841420 0059530, respectively. For three-dimensional Gaussian and Exponential models, the same region but with fewer pixels showed high dielectric values of approximately. However, the estimated dielectric value for the left side wall was around 3.4 for two-dimensional models and 2.3 for three-dimensional models. On the left side of the region, the PSR SP 871460 0840750 had high dielectric values of 10.6 and 10.2, as calculated by the two-dimensional Gaussian and Exponential models and approximately 13 for the three-dimensional models. The right side of the region showed approximately 3.6 dielectric values for two-dimensional models and 4 for three-dimensional models. We noticed that some pixel values showed ambiguous dielectric values (<1) during the retrieval and validation process, notably in three-dimensional models, which could be linked to incidence angle variability and model sensitivity. This indicates the model's limitation and is treated as outliers, which we rectified by optimizing the threshold. Overall, the research brought attention to the intriguing dielectric constant variation in PSRs. • Dielectric values for the Permanently Shadowed Regions (PSRs). • Chandrayaan-2 Dual Frequency Synthetic Aperture Radar (DFSAR) data. • Combining Integral Equation Model (IEM) and Artificial Neural Network (ANN). • Two- and three-dimensional Gaussian and Exponential models. [ABSTRACT FROM AUTHOR]

Abstract: Metabolic engineering to enhance production of isoprenoid metabolites for industrial and medical purposes is an important goal. The substrate for isoprenoid synthesis in plants is produced by the mevalonate pathway (MEV) in the cytosol and by the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway in plastids. A multi-gene approach was employed to insert the entire cytosolic MEV pathway into the tobacco chloroplast genome. Molecular analysis confirmed the site-specific insertion of seven transgenes and homoplasmy. Functionality was demonstrated by unimpeded growth on fosmidomycin, which specifically inhibits the MEP pathway. Transplastomic plants containing the MEV pathway genes accumulated higher levels of mevalonate, carotenoids, squalene, sterols, and triacyglycerols than control plants. This is the first time an entire eukaryotic pathway with six enzymes has been transplastomically expressed in plants. Thus, we have developed an important tool to redirect metabolic fluxes in the isoprenoid biosynthesis pathway and a viable multigene strategy for engineering metabolism in plants. [Copyright &y& Elsevier]

Background Tumor necrosis factor-alpha (TNF-α) are considered as a pro inflammatory and interleukin-10 (IL-10) anti inflammatory have been shown to predict the risk of incident of coronary artery disease (CAD). The polymorphism at promoter of TNF-α and IL-10 has been shown to increase transcriptional activity of the gene and play a important role in patho physiology of CAD. Aim of present study is to examine the impact of the TNF-α and IL-10 variant allele on various markers of the CAD and to study its relation with circulating TNF-α and IL-10 levels. Methods The −308 G/A & −238 G/A of TNF-α and −1082 G/A & −819 C/T of IL-10 gene polymorphism has been studied in 301 diagnosed CAD subjects (Age 51.50 ± 9.28; BMI 25.30 ± 3.58) and 305 healthy controls (Age 51.57 ± 9.50; BMI 24.06 ± 7.26). These polymorphism of TNF-α and IL-10 were detected by real time PCR by using Taqman SNP genotyping assay. Furthermore serum TNF-alpha and IL-10 levels were also measured by ELISA. Results Allelic and genotypic frequencies did not deviate from Hardy-Weinberg equilibrium in the controls ( p  > 0.05). On allele contrast, significant association with susceptibility to CAD was detected with polymorphisms in TNF-α -308 G/A, that variant genotype GA + AA (dominant model) (p = 0.030: OR = 1.61: 95% CI = 1.06–2.44) and variant allele (A) (p = 0.006: OR = 1.71: 95% CI = 1.17–2.51) of TNF-α 308 G/A gene was significant highly observed in the cases as compared to control group. Furthermore, variant genotype CT + TT (dominant model) (p = 0.004: OR = 1.62: 95% CI = 1.17–2.24) and variant allele (T) (p < 0.001: OR = 1.49: 95% CI = 1.17–1.89) of IL-10 −819 C/T gene was significant highly observed in the cases as compared to control group. Conclusion Our results suggest that the TNF-α G-308A polymorphism independently associated with DBP, cholesterol, triglyceride, LDL, TNF-α and IL-10 levels which may be leads to the development of coronary artery disease of North Indians. [ABSTRACT FROM AUTHOR]