Double Exchange model for nanoscopic clusters

We solve the double exchange model on nanoscopic clusters exactly, and specifically consider a six-site benzene-like nanocluster. This simple model is an ideal testbed for studying magnetism in nanoclusters and for validating approximations such as the dynamical mean field theory (DMFT). Non-local correlations arise between neighboring localized spins due to the Hund's rule coupling, favoring a short-range magnetic order of ferro- or antiferromagnetic type. For a geometry with more neighboring sites or a sufficiently strong hybridization between leads and the nanocluster, these non-local correlations are less relevant, and DMFT can be applied reliably.Comment: 9 pages, 9 figures, 1 tabl

DEVELOPMENT AND VALIDATION OF RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF LAMIVUDINE AND ZIDOVUDINE IN BULK

Objective: The scope of the present work is to expand and optimization of the chromatographic conditions and to develop RP-HPLC method. Methods: The method was performed with various columns like C18 column, kromasil column, Hypersil BDS column. Among them, Symmetry C18 (250x4.6 mm, 5um) was found to be ideal as it gave good peak shape at 0.8 ml/min flow and validated for various parameters such as linearity, precision, accuracy, System suitability, Specificity, % Assay, Robustness, etc. Results: The system suitability parameters were evaluated from standard chromatograms by calculating the % RSD from five replicate injections for Lamivudine and Zidovudine retention times and peak areas. The % RSD for the retention times of principal peak from 5 replicate injections of each standard solution were less than 2.0 %. The Linearity and correlation coefficient of Lamivudine and zidovudine was found to be 0.999. Precision was performed and % RSD for Lamivudine and Zidovudine were found to be less than 2.0. The % Recovery for each level was found to be the range of 98.0 to 102%. In Robustness, the % RSD of the peak area of all peaks for five replicate injections should be not more than 2.0. Conclusion: Hence, the chromatographic method developed for Lamivudine and Zidovudine is said to be rapid, simple, specific, sensitive, precise, accurate and reliable that can be effectively applied for routine analysis in research institutions, quality control department in industries, approved testing laboratories, bio-pharmaceutics and bio-equivalence studies and in clinical pharmacokinetic studies

Inducing and controlling magnetism in the honeycomb lattice through a harmonic trapping potential

We study strongly interacting ultracold spin-1/2 fermions in a honeycomb lattice in the presence of a harmonic trap. Tuning the strength of the harmonic trap we show that it is possible to confine the fermions in artificial structures reminiscent of graphene nanoflakes in solid state. The confinement on small structures induces magnetic effects which are absent in a large graphene sheet. Increasing the strength of the harmonic potential we are able to induce different magnetic states, such as a N\ue9el-like antiferromagnetic or ferromagnetic state, as well as mixtures of these basic states. The realization of different magnetic patterns is associated with the terminations of the artificial structures, in turn controlled by the confining potential

Utilization of 340b Program in a Rural Hospital

Introduction: The 340B is a federal program that provides eligible rural hospitals, providers, and clinics the capability to purchase medications at reduced prices for outpatient use. Enrollment in the 340B program requires drug manufacturers to supply covered healthcare entities and eligible healthcare organizations medications at substantially reduced prices and has allowed covered entities to extend federal resources by offering more comprehensive services and reaching more of the vulnerable populations. The purpose of this research study was to examine utilization of 340B program within provider based clinics of a university medical school affiliated with a rural hospital to assess the benefits and barriers of its utilization. Methodology: The methodology for this study was a literature review complemented with a semi-structured interview of an expert in 340B program. Seven electronic databases were utilized with a total of 21 sources referenced for this review. Results: The type and volume of care provided in rural areas has been expanded as a result of the 340B program leading to median savings of $10,000 per month in prescription purchases. Pharmacy savings have ranged from$600 to $158,000 per month depending upon whether chemotherapy was available on an outpatient basis or not. In 2010, total cost of drug discounts equaled$6 billion dollars, and has been projected to be $12 billion by 2016 with a discount range between 30% to 50%. Discussion/Conclusion: The results of this study suggest that the benefits in the types and volume of services provided outweigh the barriers of maintaining separate drug inventories and difficulties in the management of the outpatient pharmacy that include audits at the state and federal levels as well as audits from pharmaceutical manufacturers

Coupling dye degradation and biodiesel production by Geitlerinema sp TRV27

In this study, the dye degrading the ability of marine cyanobacteria, Geitlerinema sp TRV27 was tested against the textile dye Acid black 52. Optimum conditions like pH, temperature, dye concentration for acid black 52 dye degradation were studied and were found to be pH 7, 25±2°C. More than 50% of degradation was observed for the tested maximum dye concentration, 100 ppm. The degraded dye intermediate was found to be naphthalene by GC-MS analysis and their toxicity on seed germination was studied. The dye treated biomass was used for the production of biodiesel and the physicochemical properties of biofuel were found to be within the standard limits

Encyclopedia of Consciousness

The first part of this article focuses on summarizing the empirical findings on dream content, such as the universality of dream themes, the specific but general dream elements, and the occurrence and content of bad dreams and nightmares. The second part of the article reviews the currently influential theories explaining dream content data, for instance, psychoanalytic theories, random activation theories, continuity hypothesis, psychological healing function of dreams, and several theories on the evolutionary functions of dreams. © 2009 Elsevier Inc. All rights reserved.</p

Effects of ageing on pro-arrhythmic ventricular phenotypes in incrementally paced murine Pgc1β-/- hearts

A range of chronic clinical conditions accompany cardiomyocyte energetic dysfunction and constitute independent risk factors for cardiac arrhythmia. We investigated pro-arrhythmic and arrhythmic phenotypes in energetically deficient C57BL mice with genetic ablation of the mitochondrial promoter peroxisome proliferator activated receptor-γ coactivator-1β (Pgc-1β), a known model of ventricular arrhythmia. Pro-arrhythmic and cellular action potential (AP) characteristics were compared in intact Langendorff-perfused hearts from young (12-16 week) and aged (>52 week), WT and Pgc-1β-/- mice. Simultaneous electrocardiographic and intracellular microelectrode recordings were made through successive trains of 100 regular stimuli at progressively incremented heart rates. Aged Pgc-1β-/- hearts displayed an increased incidence of arrhythmia compared to other groups. Young and aged Pgc-1β-/- hearts showed higher incidences of alternans in both AP activation (maximum AP upshoot velocity (dV/dt)max and latency), recovery (action potential duration (APD90) and resting membrane potential (RMP)) characteristics compared to WT hearts. This was particularly apparent at lower pacing frequencies. These findings accompanied reduced (dV/dt)max and increased AP latency values in the Pgc-1β-/- hearts. APs observed prior to termination of the protocol showed lower (dV/dt)max and longer AP latencies, but indistinguishable APD90 and RMPs in arrhythmic compared to non-arrhythmic hearts. APD restitution analysis showed that Pgc-1β-/- and WT hearts showed similar limiting gradients. However, Pgc-1β-/- hearts had shortened plateau AP wavelengths, particularly in aged Pgc-1β-/- hearts. Pgc-1β-/- hearts therefore show pro-arrhythmic instabilities attributable to altered AP conduction and activation rather than recovery characteristics.We acknowledge the financial support from the Medical Research Council (MR/M001288/1); the Wellcome Trust (105727/Z/14/Z); the British Heart Foundation (PG/14/79/31102 and PG/15/12/31280), Sudden arrhythmic death syndrome (SADS) UK; The McVeigh Benefaction and by the Fundamental Research Grant Scheme (FRGS/2/2014/SKK01/PERDANA/02/1), Ministry of Education, Malaysia