A core-envelope massive distribution with a parabolic density distribution in the core

Tohnan's V solution has found wide application to the redshift problem in astrophysics but it has a drawback in that there is singularity at the centre. We have developed a core-envelope model with a parabolic density distribution in the core ande ^v r ²ⁿ in the envelope. The most distinctive feature of the model is that there is a continuity of all the four variables (E, P, andv) at the boundary. In other analytic coreenvelope models the continuity of only three variables is possible. This two-density structure has been used to model neutron stars and their mass, size and red shifts have been obtained.     

Synthese einiger Oxazolin-5-one

Ohne Zusammenfassung     

ROCS-derived features for virtual screening

Rapid overlay of chemical structures (ROCS) is a standard tool for the calculation of 3D shape and chemical (“color”) similarity. ROCS uses unweighted sums to combine many aspects of similarity, yielding parameter-free models for virtual screening. In this report, we decompose the ROCS color force field into color components and color atom overlaps, novel color similarity features that can be weighted in a system-specific manner by machine learning algorithms. In cross-validation experiments, these additional features significantly improve virtual screening performance relative to standard ROCS.     

Numerical Simulation of the Influence of Rough Bone-Callus Interface on the Healing of Fractured Bone

The process of healing of fractured bone is known to be influenced by the mechanical environment and the loads exerted by physical activity of the patient or otherwise. We compute mechanical fields in the soft connective tissue of the healing fracture using Biot's poroelasticity model and a finite element (FE) method for low-frequency loading. A two-scale FE framework is used to model effects of the rough bone-callus contact surface. We look at the difference the interface roughness makes with respect to different possible mechanostimulating agents.     

Computational investigation of drug bank compounds against 3C-like protease (3CLpro) of SARS-CoV-2 using deep learning and molecular dynamics simulation

Blocking the main replicating enzyme, 3 Chymotrypsin-like protease (3CL^pro) is the most promising drug development strategy against the SARS-CoV-2 virus, responsible for the current COVID-19 pandemic. In the present work, 9101 drugs obtained from the drug bank database were screened against SARS-CoV-2 3CL^pro prosing deep learning, molecular docking, and molecular dynamics simulation techniques. In the initial stage, 500 drug-screened by deep learning regression model and subjected to molecular docking that resulted in 10 screened compounds with strong binding affinity. Further, five compounds were checked for their binding potential by analyzing molecular dynamics simulation for 100 ns at 300 K. In the final stage, two compounds {4-[(2s,4e)-2-(1,3-Benzothiazol-2-Yl)-2-(1h-1,2,3-Benzotriazol-1-Yl)-5-Phenylpent-4-Enyl]Phenyl}(Difluoro)Methylphosphonic Acid and 1-(3-(2,4-dimethylthiazol-5-yl)-4-oxo-2,4-dihydroindeno[1,2-c]pyrazol-5-yl)-3-(4-methylpiperazin-1-yl)urea were screened as potential hits by analyzing several parameters like RMSD, Rg, RMSF, MMPBSA, and SASA. Thus, our study suggests two potential drugs that can be tested in the experimental conditions to evaluate the efficacy against SARS-CoV-2. Further, such drugs could be modified to develop more potent drugs against COVID-19.

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π-Hydrogen bonding wins over conventional hydrogen bonding interaction: a jet-cooled study of indole···furan heterodimer

In this study, we have explored the conformational landscape of the indole···furan dimer in a supersonic jet by using resonant two-photon ionization (R2PI) and IR-UV double-resonance spectroscopic techniques combined with dispersion-corrected density functional theory (DFT) calculations. Only one conformer of the dimer has been observed in the experiment. DFT/B97-D level calculation shows that N-H···π hydrogen-bonded conformer (T') is energetically more stable than the N-H···O hydrogen-bonded conformer (HB). Natural bond orbital (NBO) calculation also shows that the hydrogen-bonding interaction in the HB conformer is very weak. Finally, the structure of the observed dimer has been determined to be tilted T-shaped N-H···π hydrogen-bonded (T') from very excellent agreement between experimental and theoretical N-H stretch frequency. The most significant finding of this study is the first-time observation of a N-H···π bound conformer of a dimer, which wins over a conventional hydrogen-bonded conformer of the dimer.     

All good things come in threes—Three beads learn to swim with lattice Boltzmann and a rigid body solver

We simulate the self-propulsion of devices in a fluid in the regime of low Reynolds numbers. Each device consists of three bodies (spheres or capsules) connected with two damped harmonic springs. Sinusoidal driving forces compress the springs which are resolved within a rigid body physics engine. The latter is consistently coupled to a 3D lattice Boltzmann framework for the fluid dynamics. In simulations of three-sphere devices, we find that the propulsion velocity agrees well with theoretical predictions. In simulations where some or all spheres are replaced by capsules, we find that the asymmetry of the design strongly affects the propelling efficiency.     

Phytochemical study of essential oil from the aerial parts of Coleus aromaticus Benth

The essential oil composition of Coleus aromaticus Benth. (family Lamiaceae) was examined by capillary GC and GC-MS. Analyses revealed the presence of 28 constituents, of which 16 were identified. Thymol (83.39%) was found to be the major compound, while 1-octen-3-ol, terpine-4-ol, eugenol, trans-caryophyllene, caryophyllene oxide and α-cadinol were present as minor constituents.     

Chemical composition of the essential oil of Feronia elephantum Correa

The essential oil composition of Feronia elephantum Correa (family: Rutaceae) was examined by capillary gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). The analysis revealed the presence of 24 constituents, of which 18 constituents were identified. Trans-anethole (57.73%) and methyl chavicol (37.48%) were the major compounds, while cis-anethole, p-anisaldehyde, (E)-jasmone, methyl eugenol, β-caryophyllene, linalool and (E)-methyl isoeugenol were also present as the minor constituents.