Effect of disorder on the electronic properties of graphene: a theoretical approach

In order to manipulate the properties of graphene, its very important to understand the electronic structure in presence of disorder. We investigate, within a tight-binding description, the effects of disorder in the on-site (diagonal disorder) term in the Hamiltonian as well as in the hopping integral (off-diagonal disorder) on the electronic dispersion and density of states by augmented space recursion method. Extrinsic off-diagonal disorder is shown to have dramatic effects on the two-dimensional Dirac-cone, including asymmetries in the band structures as well as the presence of discontinuous bands in certain limits. Disorder-induced broadening, related to the scattering length (or life-time) of electrons, is modified significantly with the increasing strength of disorder. We propose that our theory is suitable to study the effects of disorder in other 2D materials, e.g., a boron nitride monolayer.Comment: 11 pages, 8 figure

Lattice thermal conductivity of disordered binary alloys : a formulation

We present here a formulation for the calculation of the configuration averaged lattice thermal conductivity in random alloys. Our formulation is based on the augmented-space theorem, introduced by one of us, combined with a generalized diagrammatic technique. The diagrammatic approach simplifies the problem of including effects of disorder corrections to a great extent. The approach allows us to obtain an expression for the effective heat current in case of disordered alloys, which in turn is used in a Kubo-Greenwood type formula for the thermal conductivity. We show that disorder scattering renormalizes the phonon propagators as well as the heat currents. The corrections to the current terms have been shown to be related to the self-energy of the propagators. We also study the effect of vertex corrections in a simplified ladder diagram approximation. A mode dependent diffusivity $D_{\gamma}$ and then a total thermal diffusivity averaged over different modes are defined. Schemes for implementing the said formalism are discussed. A few initial numerical results on the frequency and temperature dependence of lattice thermal conductivity are presented for NiPd alloy and are also compared with experiment. We also display numerical results on the frequency dependence of thermal diffusivity averaged over modes.Comment: 16 pages, 17 figure

Inelastic neutron scattering in random binary alloys : an augmented space approach

Combining the augmented space representation for phonons with a generalized version of Yonezawa-Matsubara diagrammatic technique, we have set up a formalism to seperate the coherent and incoherent part of the total intensity of thermal neutron scattering from disordered alloys. This is done exacly without taking any recourse to mean-field like approximation (as done previously). The formalism includes disorder in masses, force constants and scattering lengths. Implementation of the formalism to realistic situations is performed by an augmented space Block recursion which calculates entire Green matrix and self energy matrix which in turn is needed to evaluate the coherent and incoherent intensities. we apply the formalism to NiPd and NiPt alloys. Numerical results on coherent and incoherent scattering cross sections are presented along the highest symmetry directions. Finally the incoherent intensities are compared with the CPA and also with experiments.Comment: 18 pages, 13 figure

Comparison of Efficiencies of Neurological Physical Examination, Neurothesiometer and PainDETECT Questionnaire in Diagnosing Diabetic Neuropathy

Objective: To compare the efficacies of neurological physical examination, neurothesiometer and PainDETECT questionnaire in diagnosing diabetic neuropathy. Study Design: Prospective cross-sectional Place and Duration of Study: Department of General Medicine, Nishtar Hospital Multan, Pakistan from 1st December 2018 to 10th March 2019. Materials and Methods: One hundred and four patients of both type 1 and type 2 diabetes visiting the outdoor department were included in this study. They were assessed by lab results of glycosylated hemoglobin, fasting and random blood sugar levels and neurological physical examination. Results: The physical examination with Michigan Neuropathy Screening instrument showed that around 29 of the patients were having established neuropathy. The PainDETECT questionnaire on the other hand showed about 42 patients having a definitive neuropathy while the neurothesiometer showed that 79 of the total patients had varying degrees of neuropathy. Conclusion: The neurothesiometer is a better diagnostic tool for diagnosing diabetic neuropathy in patients

Structural Properties and Relative Stability of (Meta)Stable Ordered, Partially-ordered and Disordered Al-Li Alloy Phases

We resolve issues that have plagued reliable prediction of relative phase stability for solid-solutions and compounds. Due to its commercially important phase diagram, we showcase Al-Li system because historically density-functional theory (DFT) results show large scatter and limited success in predicting the structural properties and stability of solid-solutions relative to ordered compounds. Using recent advances in an optimal basis-set representation of the topology of electronic charge density (and, hence, atomic size), we present DFT results that agree reasonably well with all known experimental data for the structural properties and formation energies of ordered, off-stoichiometric partially-ordered and disordered alloys, opening the way for reliable study in complex alloys.Comment: 7 pages, 2 figures, 2 Table

Mortality caused by aqueous extract of the leaves of Datura stramineus to goat biting louse, Bovicola caprae (Phthiraptera)

Extensive and indiscriminate use of organic lousicides is leading to environmental hazards i.e. persistence of residues, development of resistance and targeting of non-target beneficial organism. Hence, phytotherapy is emerging as effective tool for louse control, due to ecofriendly and biodegradable nature of plant extracts. In the present study the mortality and repellency caused by five concentration of aqueous extract of the leaves of commonly available Datura stramineus were tested against goat biting louse, Bovicola caprae. Fifteen percent concentration of extract prepared from leaves of aforesaid plant imparted 77% mortality and 66% repellency to goat biting louse

Lattice thermal conductivity of disordered NiPd and NiPt alloys

Numerical calculations of lattice thermal conductivity are reported for the binary alloys NiPd and NiPt. The present work is a continuation of an earlier paper by us [PRB, 72, 214207 (2005)]which had developed a theoretical framework for the calculation of configuration-averaged lattice thermal conductivity and thermal diffusivity in disordered alloys. The formulation was based on the augmented space theorem combined with a scattering diagram technique. In this paper we shall show dependence of the lattice thermal conductivity on a series of variables like phonon frequency, temperature and alloy composition. The temperature dependence of $\kappa(T)$ and its realtion to the measured thermal conductivity is discussed. The concentration dependence of $\kappa$ appears to justify the notion of a minimum thermal conductivity as discussed by Kittel, Slack and others. We also study the frequency and composition dependence of the thermal diffusivity averaged over modes. A numerical estimate of this quantity gives an idea about the location of mobility edge and the fraction of states in the frequency spectrum which is delocalized.Comment: 23 pages, 18 figure

Establishment of Dipstick Development Technology for Detection of Cry1Ac in Transgenic Plants

The insecticidal Bt Cry1Ac protein is, currently used for transgene expression in numerous crops or deliberating resistance against lepidopteron pests. Since the introduction of Bt cotton in Pakistan. It has been demonstrated that the technology has achieved the goal of providing an effective tool for lepidopteron control. In this study, single step, sensitive and specific dipstick strip test for the revealing of recombinant Cry1Ac protein in the transgenic plants was established. Anti-Bt-Cry1Ac antibodies and goat anti-rabbit IgG antibodies were used in test and control lines, respectively. The distance betweenthese lines were optimized as 0.5 cm. Polyclonal rabbit anti Bt-Cry1Ac antibody conjugated to nanocolloidal gold (20 nm of OD 15 and 40 nm; OD 1 in separate experiments) at pH 9.2 was used to serve as a probe for detecting Cry1Ac protein in transgenic Bt cotton samples. Both conjugate solutions were coated on separate polyester conjugate pads (0.7 cm × 0.5 cm). The total size of strip was 7.5 cm × 0.5 cm. For 20 nm gold conjugated strip, purple color test line and for 40 nm gold red color test line indicated the binding of gold labeled antibodies to antigen. The assay was corroborated with transgenic cotton samples with protein extraction buffer 1X PBS of pH 7. This on-site test offers fast screening for any genetically modified crop devouring Cry1Ac transgenic protein

Recommendations for coronavirus infection in rheumatic diseases treated with biologic therapy.

The Coronavirus-associated disease, that was first identified in 2019 in China (CoViD-19), is a pandemic caused by a bat-derived beta-coronavirus, named SARS-CoV2. It shares homology with SARS and MERS-CoV, responsible for past outbreaks in China and in Middle East. SARS-CoV2 spread from China where the first infections were described in December 2019 and is responsible for the respiratory symptoms that can lead to acute respiratory distress syndrome. A cytokine storm has been shown in patients who develop fatal complications, as observed in past coronavirus infections. The management includes ventilatory support and broad-spectrum antiviral drugs, empirically utilized, as a targeted therapy and vaccines have not been developed. Based upon our limited knowledge on the pathogenesis of CoViD-19, a potential role of some anti-rheumatic drugs may be hypothesized, acting as direct antivirals or targeting host immune response. Antimalarial drugs, commonly used in rheumatology, may alter the lysosomal proteases that mediates the viral entry into the cell and have demonstrated efficacy in improving the infection. Anti-IL-1 and anti-IL-6 may interfere with the cytokine storm in severe cases and use of tocilizumab has shown good outcomes in a small cohort. Baricitinib has both antiviral and anti-inflammatory properties. Checkpoints inhibitors such as anti-CD200 and anti-PD1 could have a role in the treatment of CoViD-19. Rheumatic disease patients taking immunosuppressive drugs should be recommended to maintain the chronic therapy, prevent infection by avoiding social contacts and pausing immunosuppressants in case of infection. National and international registries are being created to collect data on rheumatic patients with CoViD-19