Relationship between Electronic and Geometric Structures of the O/Cu(001) System

The electronic structure of the $(2\sqrt{2}\times\sqrt{2})R45^{\circ}$ O/Cu(001) system has been calculated using locally self-consistent, real space multiple scattering technique based on first principles. Oxygen atoms are found to perturb differentially the long-range Madelung potentials, and hence the local electronic subbands at neighboring Cu sites. As a result the hybridization of the oxygen electronic states with those of its neighbors leads to bonding of varying ionic and covalent mix. Comparison of results with those for the c(2x2) overlayer shows that the perturbation is much stronger and the Coulomb lattice energy much higher for it than for the $(2\sqrt{2}\times\sqrt{2})R45^{\circ}$ phase. The main driving force for the 0.5ML oxygen surface structure formation on Cu(001) is thus the long-range Coulomb interaction which also controls the charge transfer and chemical binding in the system.Comment: 17 pages, 8 figure

PHARMACOLOGICAL AND ANTI CANCER ACTIVITY OF Ipomoea sepiaria METHANOLIC EXTRACT AGAINST PC-3 CELL LINE

A few conventional restorative plants contain in explored concerning their enemy of corpulence likely wellsprings of is Ipomoea sepiaria Koenig ex. Roxb. The medicine is supposed in tales game plan of prescription for various accommodating properties like, love elixir and arsenic hurting, tonic, re-establishing, diuretic, laxative, uterotonic and sterility in women and leaves is shown particularly in diabetes. Phytochemical screening of different concentrates of Ipomoea sepiaria exposed the presence and non-attendance of various phytochemicals are available in ethanol remove, further examinations were done with leaves of Ipomoea sepiaria ethanol separate. PC3 (PC-3) is a human prostate malignancy cell lines that are profoundly utilized in examining the biochemical changes prostatic disease cells. Explores on PC-3 human prostate malignancy cell lines control are required in the current many years. The anticancer action of fluid concentrate of Ipomoea sepiaria was researched by 3-(4,5-dimethylthiazol-2-yl)- 2, 5-diphenyltetrazolium (MTT) measure utilizing PC-3 cell line. The current experimentation was indicated that watery concentrate of Ipomoea sepiaria, when exposed to various focuses on PC-3 cells demonstrated IC50 cell hindrance at about 5μM for 48 hours and about 2 μM for 72 hours. The information made by this particular examination gives relevant pharmacognostic  and phytochemical data needed for proper distinctive confirmation and check of leaves of this particular  species. &nbsp

PHYTOCHEMICAL SCREENING AND COMPARATIVE GC–MS ANALYSIS OF BIOACTIVE COMPOUNDS PRESENT IN METHANOLIC LEAF AND LATEX EXTRACT Calotropis gigantea (L)

Medicinal plants are considered as important source of promising bioactive compounds. Calotropis gigantea is a traditional medicinal plant which is known to have biochemical constituents with potential medicinal properties. Qualitative analysis showed the presence of alkaloids, terpenoids, saponins, tannins and cardiac glycosides and absence of flavonoids in ethanolic extract of C. gigantea, while the chloroform leaf extract showed absence of flavonoids and cardiac glycosides. Bioactive compounds since leaf and latex of C. gigantea utilized GC-MS and activity investigation. The GC-MS investigation uncovered the presence of complete 46 bioactive mixes (24 from leaves and 22 from latex) with significant movement. The majority of the mixes were discovered to be comparable in both leaf and latex, however little variety was likewise seen in their synthetic profile. The concoction mixes saw in just latex were 1-[(T-butyl) dimethyl silyl thin] butane, 1-Hexadecyne, Hexadecane, L-Glutamic corrosive, Phenol-3-isoproxy-5-methyl, Trocosane and Z-1,6-Tridecadiene. Mixes distinguished uniquely from the leaves were Azulene, Benalaxyl, Cis-vaccenic corrosive, Levomenol, Profenofos, β-Tocopherol and β-Sitosterol, while the remainder of the mixes were comparable in both leaf and latex. Major of bioactive compounds presents Gas Chromatography-Mass Spectroscopy (GC-MS) analysis. C. gigantea is a perennial plant abundantly found in all parts of the country (India) and wild in nature. The leaves of the plant were found to contain various primary and secondary metabolites

Multi-scale modelling to estimate spall parameters in metallic single crystals

Modeling dynamics fracture in materials involves usage of hydrodynamic codes which solve basic conservation laws of mass, energy and momentum in space and time. This requires appropriate models to handle elastic-plastic deformation, equation of state, material strength, and fracture. Nucleation and Growth (NAG) damage model is a micro-physical model which computes amount of damage in the material by accounting for phenomena like nucleation, growth and coalescence of voids or cracks. The NAG model involves several material model parameters, such as nucleation threshold, growth threshold, etc. Traditionally these parameters are fitted to experimental void volume distributions. In the present paper we fit these parameters to molecular dynamics (MD) simulations of void nucleation and growth and use the fitted parameters in hydrodynamic simulations in a multi-scale computational approach. Cubic metallic single crystals are subjected to isotropic deformation and the nucleation of voids and their growth were post-processed from the simulations. These results are used in an in-house Particle Swarm Optimization (PSO) code to obtain NAG parameters for materials of our interest. Using these parameters in a 1D hydrodynamic code developed in-house, fracture parameters such as spall strength and thickness are obtained. The results are validated with published experimental data for Mo, Nb and Cu which have been simulated using the multi-scale model. This paper describes the application of the multi-scale model to obtain the NAG fracture model parameters of Al and its spall data. The results are compared with published experimental results in single crystal Al.Comment: 8 pages, 10 figures, 2 table

Unique gap structure and symmetry of the charge density wave in single-layer VSe2_2

Single layers of transition metal dichalcogenides (TMDCs) are excellent candidates for electronic applications beyond the graphene platform; many of them exhibit novel properties including charge density waves (CDWs) and magnetic ordering. CDWs in these single layers are generally a planar projection of the corresponding bulk CDWs because of the quasi-two-dimensional nature of TMDCs; a different CDW symmetry is unexpected. We report herein the successful creation of pristine single-layer VSe$_2$, which shows a ($\sqrt7 \times \sqrt3$) CDW in contrast to the (4 $\times$ 4) CDW for the layers in bulk VSe$_2$. Angle-resolved photoemission spectroscopy (ARPES) from the single layer shows a sizable ($\sqrt7 \times \sqrt3$) CDW gap of $\sim$100 meV at the zone boundary, a 220 K CDW transition temperature twice the bulk value, and no ferromagnetic exchange splitting as predicted by theory. This robust CDW with an exotic broken symmetry as the ground state is explained via a first-principles analysis. The results illustrate a unique CDW phenomenon in the two-dimensional limit

STM conductance of Kondo impurities on open and structured surfaces

We study the scanning tunneling microscopy response for magnetic atoms on open and structured surfaces using Wilson's renormalization group. We observe Fano resonances associated with Kondo resonances and interference effects. For a magnetic atom in a quantum corral coupled to the confined surface states, and experimentally relevant parameters, we observe a large confinement induced effect not present in the experiments. These results suggest that the Kondo screening is dominated by the bulk electrons rather than the surface ones.Comment: 6 pages, 6 figure

Interactive effects of cocaine on HIV infection: implication in HIV-associated neurocognitive disorder and neuroAIDS.

Substantial epidemiological studies suggest that not only, being one of the reasons for the transmission of the human immunodeficiency virus (HIV), but drug abuse also serves its role in determining the disease progression and severity among the HIV infected population. This article focuses on the drug cocaine, and its role in facilitating entry of HIV into the CNS and mechanisms of development of neurologic complications in infected individuals. Cocaine is a powerfully addictive central nervous system stimulating drug, which increases the level of neurotransmitter dopamine (DA) in the brain, by blocking the dopamine transporters (DAT) which is critical for DA homeostasis and neurocognitive function. Tat protein of HIV acts as an allosteric modulator of DAT, where as cocaine acts as reuptake inhibitor. When macrophages in the CNS are exposed to DA, their number increases. These macrophages release inflammatory mediators and neurotoxins, causing chronic neuroinflammation. Cocaine abuse during HIV infection enhances the production of platelet monocyte complexes (PMCs), which may cross transendothelial barrier, and result in HIV-associated neurocognitive disorder (HAND). HAND is characterized by neuroinflammation, including astrogliosis, multinucleated giant cells, and neuronal apoptosis that is linked to progressive virus infection and immune deterioration. Cocaine and viral proteins are capable of eliciting signaling transduction pathways in neurons, involving in mitochondrial membrane potential loss, oxidative stress, activation of JNK, p38, and ERK/MAPK pathways, and results in downstream activation of NF-κB that leads to HAND. Tat-induced inflammation provokes permeability of the blood brain barrier (BBB) in the platelet dependent manner, which can potentially be the reason for progression to HAND during HIV infection. A better understanding on the role of cocaine in HIV infection can give a clue in developing novel therapeutic strategies against HIV-1 infection in cocaine using HIV infected population

PHYTOCHEMICALS SCREENING OF PHYSICO-CHEMICAL PARAMETERS AND FLUORESCENCE ANALYSIS OF PLANT ETHANOLIC LEAF EXTRACT Costus pictus

Drugs originating from plant sources are reflection to be a promising alternative for other synthetic anti-diabetics such as sulphonylureas, insulin treatment and biguanides. Plant products are believed to more preferable due to less toxicity, economic and better patient compliance. Hence, medicinal plants and products thereof are used in many countries in the treatment and management of diabetes. Vitamins are organic substances that are essential in minute amounts designed for the growth and activity of the body. They are obtained naturally on or after plant and animal foods. Organic in this definition refers in the direction of the chemistry with molecules. The word organic means that the molecules of substance contain the element carbon. The term also means that vitamins can be destroyed and become unable to perform their functions in our bodies. Every component plays an important role and deficiency of anyone constituent may lead to abnormal developments in the body. Plants are a rich source of all the elements essential for a human being. Qualitative analysis of various inorganic elements revealed the presence of calcium, magnesium, potassium, Iron, sulphates and phosphates. The present study of a good source of pharmacognostical and physicochemical parameters have pivotal roles in identification, authentication and establishment of quality parameters and vitamins of the species. Supplementation of this Costus pictus may be useful for human health associated emerging diseases such as diabetes, hypertension and cancer. &nbsp

Projecting the Kondo Effect: Theory of the Quantum Mirage

A microscopic theory is developed for the projection (quantum mirage) of the Kondo resonance from one focus of an elliptic quantum corral to the other focus. The quantum mirage is shown to be independent of the size and the shape of the ellipse, and experiences \lambda_F/4 oscillations (\lambda_F is the surface-band Fermi wavelength) with an increasing semimajor axis length. We predict an oscillatory behavior of the mirage as a function of a weak magnetic field applied perpendicular to the sample.Comment: 4 pages 2 figures include