4,400 research outputs found
Solving quantum master equations in phase space by continued-fraction methods
Inspired on the continued-fraction technique to solve the classical
Fokker--Planck equation, we develop continued-fraction methods to solve quantum
master equations in phase space (Wigner representation of the density matrix).
The approach allows to study several classes of nonlinear quantum systems
subjected to environmental effects (fluctuations and dissipation), with the
only limitations that the starting master equations may have. We illustrate the
method with the canonical problem of quantum Brownian motion in periodic
potentials.Comment: 7 pages, 3 figure
A study of fasting lipid profile in chronic kidney disease patients
Background: Dyslipidemia is very much common in chronic kidney disease patients and is responsible for cardiovascular disease (CKD) which is most common cause of mortality in them. So, it is necessary to study the lipid profile in CKD patients to prevent morbidity and mortality.Methods: Subjects each of 50 in number are grouped into healthy controls (group-1), CKD patients without hemodialysis (group-2), CKD patients with hemodialysis (group-3). After fasting of 12 hours, lipid profile is assessed in all cases.Results: In this study, there is increase in Total cholesterol (TC), Low Density lipoprotein (LDL), very Low-Density lipoprotein (VLDL) and Triglycerides (TG) and decrease in High Density Lipoprotein (HDL) in all CKD patients compared to healthy controls (p-value for each parameter <0.001). There is increase in TC, TG and VLDL in diabetic CKD patients compare to non-diabetic CKD patients and p-value for each parameter is <0.05. It was found that TG and VLDL increase and HDL decrease in group-3 compare to group-2 is statistically significant (p-value for each <0.05) and no significant variation in TC and LDL in these groups.Conclusions: Present study demonstrated that there is dyslipidemia in CKD patients irrespective of mode of management, but the derangement is much more common and significant in CKD with hemodialysis group and they are at risk of cardiovascular disease. It is better to start lipid lowering drugs which decreases disease progression and dyslipidemia
Study of algal flora of Navapur, District Nandurbar,Maharashtra, India.
The river Rangawali from Navapur of Nandurbar district ( the district Nandurbar formerly known as west Khandesh lies in upper Tapi basin in the North-West corner of Maharashtra) was selected for taxonomical enumeration of algae. Algal samples were collected from five stations of Rangawali river for a period of one year (October 2006- September 2007). In this communication chlorophyceae is studied taxonomically. 27 species belonging to 10 genera were recorded. Genus Scenedesmus was observed dominant. This is first report from this rural area of Khandesh of Maharashtra
Effect of Austenitization Temperature on Wear Behavior of Carbidic Austempered Ductile Iron (CADI)
Chromium bearing Austempered Ductile Iron (ADI) has been recently in the news for its improved wear performance over the ADI. The work presented below was taken up to study the effect of different austenitisation temperatures on the microstructure and wear performance of the Carbidic Austempered Ductile Iron (CADI). In this investigation Cr bearing ductile iron was subjected to austempering treatment to obtain an ausferritic microstructure. Two different austenitisation temperatures were selected whereas, the austempering temperature and time was kept unchanged. Microstructure and wear performance of this alloy, austenitized at two different temperatures was studied
Effect of Austenitization Temperature on Wear Behavior of Carbidic Austempered Ductile Iron (CADI)
Chromium bearing Austempered Ductile Iron (ADI) has been recently in the news for its improved wear performance over the ADI. The work presented below was taken up to study the effect of different austenitisation temperatures on the microstructure and wear performance of the Carbidic Austempered Ductile Iron (CADI). In this investigation Cr bearing ductile iron was subjected to austempering treatment to obtain an ausferritic microstructure. Two different austenitisation temperatures were selected whereas, the austempering temperature and time was kept unchanged. Microstructure and wear performance of this alloy, austenitized at two different temperatures was studied
Beneficiation of low grade graphite ore from Multai area, Betul district, M.P.
The low grade graphite ore sample from Multai area, Betul District, M.P analysed 10% graphite and wasfound to be crvptocrystalline in nature and intimately associated with silicate gangue. Conventional mechanical cell flotation trials were conducted and various process variables such as
froth erlcollector/depressant concentrations, pH of the pulp etc., were optimised. The best grade concentrate containing 60.1% F.C. was obtained after cleaning the rougher concentrate twice, with a recovery of 72.12%.
Further improvement in the grade was possible by only resorting to the bulk oil flotation of the finely ground sample (less than 37 microns). The best grade containing 72.5% F.C. was obtained by bulk oil flotation of the
rougher concentrate containing 53.7% F.C., with an overall graphite recovery of 74.6%. The column flotation trials studying process variables such as pulp density,depressant concentration and airflow rates, yielded the best grade of column concentrate containing 64% F.C. with a recovery
of90.88%. Afteranalysing the results obtained by various techniques critically, the bulk oil flotation of the rougher cell concentrate, was found to be the most suitable technique
Electroluminescence from Organometallic Lead Halide Perovskite-Conjugated Polymer Diodes
Organometallic lead perovskite-based solar cells can be converted to light-emitting diodes by engineering the current density. Diodes are fabricated with adjacent perovskite and conjugated polymer layers using orthogonal solvents. Under forward bias, these devices show simultaneous emission from both the luminescent conjugated polymer and the perovskite, providing direct information on electron and hole recombination as a function of device architecture and bias voltage.We gratefully acknowledge funding from the Engineering and Physical Sciences Research Council (EPSRC). A.K. acknowledges NRF-Singapore for a scholarship.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/aelm.20150000
Čvrsta disperzija meloksikama: faktorijalno dizajnirani dozirani pripravak za gerijatrijsku populaciju
The objective of the present work was to improve the dissolution properties of the poorly water-soluble drug meloxicam by preparing solid dispersions with hydroxyethylcellulose (HEC), mannitol and polyethylene glycol (PEG) 4000 and to develop a dosage form for geriatric population. Differential scanning calorimetry, X–ray diffractometry, Fourier transform infrared spectroscopy and scanning electron microscopy were used to investigate the solid-state physical structure of the prepared solid dispersions. Higher in vitro dissolution of solid dispersions was recorded compared to their corresponding physical mixtures and the pure drug. PEG 4000 in 1:9 drug to carrier ratio exhibited the highest drug release (100.2%), followed by mannitol (98.2%) and HEC (89.5%) in the same ratio. Meloxicam-PEG 4000 solid dispersion was formulated into suspension and optimization was carried out by 23 factorial design. Formulations containing higher levels of methyl cellulose and higher levels of either sodium citrate or Tween 80 exhibited the highest drug release.Cilj rada bio je poboljšati topljivost meloksikama u vodi pripravom čvrstih disperzija s hidroksietilcelulozom (HEC), manitolom i polietilen glikolom 4000 (PEG 4000) te razviti dozirani pripravaka za gerijatrijsku populaciju. Za ispitivanje fizičke strukture pripravljenih čvrstih disperzija korištene su diferencijalna pretražna kalorimetrija, difraktometrija rentgentskim zrakama, FTIR i pretražna elektronska mikroskopija. Čvrste disperzije su u in vitro uvjetima pokazale bolju topljivost u odnosu na fizičku smjesu i čistu ljekovitu tvar. Najbolje oslobađanje lijeka (100,2%). postignuto je iz disperzija s PEG 4000 (omjer ljekovite tvari i nosača 1:9). Slijede manitol (98,2%) i HEC (89,5%) (isti omjer meloksikama i polimera). Čvrsta disperzija meloksikama s PEG 4000 prevedena je u suspenziju te optimirana 23 faktorijalnim dizajnom. Najbolje oslobađanje ljekovite tvari postignuto je iz pripravaka koji sadrže veći udio etilceluloze i natrijevog citrata, odnosno Tween 80
Inelastic X-ray scattering study of the collective dynamics in liquid sodium
Inelastic X-ray scattering data have been collected for liquid sodium at
T=390 K, i.e. slightly above the melting point. Owing to the very high
instrumental resolution, pushed up to 1.5 meV, it has been possible to
determine accurately the dynamic structure factor, , in a wide
wavevector range, nm, and to investigate on the dynamical
processes underlying the collective dynamics. A detailed analysis of the
lineshape of , similarly to other liquid metals, reveals the
co-existence of two different relaxation processes with slow and fast
characteristic timescales respectively. The present data lead to the conclusion
that: i) the picture of the relaxation mechanism based on a simple viscoelastic
model fails; ii) although the comparison with other liquid metals reveals
similar behavior, the data do not exhibit an exact scaling law as the principle
of corresponding state would predict.Comment: RevTex, 7 pages, 6 eps figures. Accepted by Phys. Rev.
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