Reflection of Vitamins and Mineral Deficiency in General Health Condition: Article Review

Vitamins are organic substances that humans require in trace amounts. Each plays a distinct part in preserving physical well-being. To increase their supply, some people require supplements; however, this is dependent on their lifestyle and general health. Vitamins are necessary nutrients of the body\u27s healthy growth and operation. Vitamins are divided into two classes:  fat and water soluble. Inorganic elements, known as minerals, are derived from food and cannot be produced by the body. Collecting all types of vitamins in a study their sources, functions, excess and deficiency. They have an effective role in the body’s metabolism and immunity and in combating most diseases that affect the human body. Balancing them in moderate concentrations in the human body protects against the risk of contracting many diseases that affect adults and children. Therefore, every individual must take adequate food. It contains all types of vitamins, and in case of deficiency, it is compensated with manufactured vitamins

Chandra Reveals Heavy Obscuration and Circumnuclear Star Formation in Seyfert 2 Galaxy NGC 4968

We present the Chandra imaging and spectral analysis of NGC 4968, a nearby (z = 0.00986) Seyfert 2 galaxy. We discover extended ($\sim$1 kpc) X-ray emission in the soft band (0.5 - 2 keV) that is neither coincident with the narrow line region nor the extended radio emission. Based on spectral modeling, it is linked to on-going star formation ($\sim$2.6-4 M_{\sun} yr$^{-1}$). The soft emission at circumnuclear scales (inner $\sim$400 pc) originates from hot gas, with kT $\sim$ 0.7 keV, while the most extended thermal emission is cooler (kT $\sim$ 0.3 keV). We refine previous measurements of the extreme Fe K$\alpha$ equivalent width in this source (EW = 2.5$^{+2.6}_{-1.0}$ keV), which suggests the central engine is completely embedded within Compton-thick levels of obscuration. Using physically motivated models fit to the Chandra spectrum, we derive a Compton-thick column density ($N_{\rm H} > 1.25\times10^{24}$ cm$^{-2}$) and an intrinsic hard (2-10 keV) X-ray luminosity of $\sim$3-8$\times 10^{42}$ erg s$^{-1}$ (depending on the presumed geometry of the obscurer), which is over two orders of magnitude larger than that observed. The large Fe K$\alpha$ EW suggests a spherical covering geometry, which could be confirmed with X-ray measurements above 10 keV. NGC 4968 is similar to other active galaxies that exhibit extreme Fe K$\alpha$ EWs (i.e., $>$2 keV) in that they also contain ongoing star formation. This work supports the idea that gas associated with nuclear star formation may increase the covering factor of the enshrouding gas and play a role in obscuring AGN.Comment: 11 pages, 8 figures, 4 tables. Accepted for publication in Ap

The Importance of Static Correlation in the Band Structure of High Temperature Superconductors

Recently we presented a new band structure for La(2-x)Sr(x)CuO(4) and other high temperature superconductors in which a second narrow band was seen to cross the primary band at the Fermi level. The existence of this second Fermi level band is in complete disagreement with the commonly accepted LDA band structure. Yet it provided a crucial piece of physics which led to an explanation for superconductivity and other unusual phenomena in these materials. In this work we present details as to the nature of the failure of conventional methods in deriving the band structure of the cuprates. In particular, we use a number of chemical analogues to describe the problem of static correlation in the band structure calculations and show how this can be corrected with the predictable outcome of a Fermi level band crossing.Comment: The Journal of Physical Chemistry, in press. References and figures updated. See www.firstprinciples.com for more information related to this wor

Electron Correlation and the c-axis Dispersion of Cu d_z^2: a New Band Structure for High Temperature Superconductors

Previously we showed the major effect of electron correlation in the cuprate superconductors is to lower the energy of the Cu d_x^2-y^2/O p_sigma (x^2-y^2) band with respect to the Cu d_z^2/O' p_z (z^2) band. In our 2D Hubbard model for La_1.85Sr_0.15CuO_4 (LaSCO), the z^2 band is narrow and crosses the standard x^2-y^2 band just below the Fermi level. In this work, we introduce c-axis dispersion to the model and find the z^2 band to have considerable anisotropic 3D character. An additional hole-like surface opens up in the z^2 band at (0,0,2pi/c) which expands with doping. At sufficient doping levels, a symmetry allowed x^2-y^2/z^2 band crossing along the (0,0)-(pi,pi) direction of the Brillouin zone appears at the Fermi level. At this point, Cooper pairs between the two bands (e.g. (k uparrow x^2-y^2/k downarrow z^2)) can form, providing the basis for the Interband Pairing Theory of superconductivity in these materials.Comment: submitted to Phys. Rev. Lett. Related publications: Phys. Rev. B 58, 12303 (1998); Phys. Rev. B 58, 12323 (1998); cond-mat/9903088; cond-mat/990310

Inheritance of fresh seed dormancy in Spanish-type peanut (Arachis hypogaea L.): bias introduced by inadvertent selfed flowers as revealed by microsatellite markers control

Production and seed quality in peanut (Arachis hypogaea L.) can be reduced substantially by in situ germination under unpredictable rainfed environments. Inheritance of fresh seed dormancy in Spanish x Spanish crosses was studied with two sets of segregating populations, an F2 population derived from true F1 hybrids identified with peanut microsatellites markers and other populations (F2, BC1P1S and BC1P2S) from randomly-selected F1 individuals. In the F2 population developed with true F1 hybrids, the chi square test was not significant for the deviation from the expected 3:1 (dormant: non-dormant) ratio. In addition, the bimodal frequency distribution curve with the F2 population gave more evidence that fresh seed dormancy is controlled by a single dominant gene. The average frequency (48%) of true F1 hybrids give evidence that deviations from expected ratios in the populations (F2 and BC1P1S) developed from non-tested F1 individuals, is most likely due to inadvertent selfs. This study emphasized the need to identify with molecular markers the cross progenies in self-pollinated crops as peanutbefore testing for any trait

The Antiferromagnetic Band Structure of La2CuO4 Revisited

Using the Becke-3-LYP functional, we have performed band structure calculations on the high temperature superconductor parent compound, La2CuO4. Under the restricted spin formalism (rho(alpha) equal to rho(beta)), the R-B3LYP band structure agrees well with the standard LDA band structure. It is metallic with a single Cu x2-y2/O p(sigma) band crossing the Fermi level. Under the unrestricted spin formalism (rho(alpha) not equal to rho(beta)), the UB3LYP band structure has a spin polarized antiferromagnetic solution with a band gap of 2.0 eV, agreeing well with experiment. This state is 1.0 eV (per formula unit) lower than that calculated from the R-B3LYP. The apparent high energy of the spin restricted state is attributed to an overestimate of on-site Coulomb repulsion which is corrected in the unrestricted spin calculations. The stabilization of the total energy with spin polarization arises primarily from the stabilization of the x2-y2 band, such that the character of the eigenstates at the top of the valence band in the antiferromagnetic state becomes a strong mixture of Cu x2-y2/O p(sigma) and Cu z2/O' p(z). Since the Hohenberg-Kohn theorem requires the spin restricted and spin unrestricted calculations give exactly the same ground state energy and total density for the exact functionals, this large disparity in energy reflects the inadequacy of current functionals for describing the cuprates. This calls into question the use of band structures based on current restricted spin density functionals (including LDA) as a basis for single band theories of superconductivity in these materials.Comment: 13 pages, 8 figures, to appear in Phys. Rev. B, for more information see http://www.firstprinciples.co

Chiral Plaquette Polaron Theory of Cuprate Superconductivity

Ab-initio density functional calculations on explicitly doped La(2-x)Sr(x)CuO4 find doping creates localized holes in out-of-plane orbitals. A model for superconductivity is developed based on the assumption that doping leads to the formation of holes on a four-site Cu plaquette composed of the out-of-plane A1 orbitals apical O pz, planar Cu dz2, and planar O psigma. This is in contrast to the assumption of hole doping into planar Cu dx2-y2 and O psigma orbitals as in the t-J model. Interaction of holes with the d9 spin background leads to chiral polarons with either a clockwise or anti-clockwise charge current. When the polaron plaquettes percolate through the crystal at x~0.05 for LaSrCuO, a Cu dx2-y2 and planar O psigma band is formed. Spin exchange Coulomb repulsion with chiral polarons leads to D-wave superconductivity. The equivalent of the Debye energy in phonon superconductivity is the maximum energy separation between a chiral polaron and its time-reversed partner. An additive skew-scattering contribution to the Hall effect is induced by chiral polarons and leads to a temperature dependent Hall effect that fits the measured values for LaSrCuO. The integrated imaginary susceptibility satisfies omega/T scaling due to chirality and spin-flip scattering of polarons along with a uniform distribution of polaron energy splittings. The derived functional form is compatible with experiments. The static spin structure factor is computed and is incommensurate with a separation distance from (pi,pi) given by ~(2pi)x. Coulomb scattering of the x2-y2 band with polarons leads to linear resistivity. Coupling of the x2-y2 band to the undoped Cu d9 spins leads to the ARPES pseudogap and its doping and temperature dependence.Comment: 32 pages, 17 figure