297 research outputs found
Density-functional calculation of ionization energies of current-carrying atomic states
Current-density-functional theory is used to calculate ionization energies of
current-carrying atomic states. A perturbative approximation to full
current-density-functional theory is implemented for the first time, and found
to be numerically feasible. Different parametrizations for the
current-dependence of the density functional are critically compared. Orbital
currents in open-shell atoms turn out to produce a small shift in the
ionization energies. We find that modern density functionals have reached an
accuracy at which small current-related terms appearing in open-shell
configurations are not negligible anymore compared to the remaining difference
to experiment.Comment: 7 pages, 2 tables, accepted by Phys. Rev.
Plasmonics of topological insulators
We discuss the plasmonic properties of chalcogenide topological insulators arising from interband transitions and Drude-like response of metallic surface states in the UV to mid-IR, which provide a new platform for electronics and photonics integration
In situ growth of redox-active iron-centered nanoparticles on graphene sheets for specific capacitance enhancement
AbstractA fast and facile approach is proposed to enhance the specific capacitance of N-Methyl-2-pyrrolidone (NMP)-exfoliated graphene. Redox-active nickel ferricyanide (NiFeCN) nanoparticles were grown on the surface of graphene sheets using a simple co-precipitation method. Apart from the synergetic effect of graphene as double layer capacitance and NiFeCN as pseudocapacitance in specific capacitance enhancement, the NiFeCN nanoparticles served as the spacer to prevent the graphene sheets agglomeration. The NiFeCN/graphene exhibited specific capacitance of 113.5Fg−1, which was 2 times higher than the NMP-exfoliated graphene (52Fg−1) and 6times higher than the pure NiFeCN (18Fg−1). The findings suggested the NiFeCN/graphene could be the potential candidate for supercapacitor electrode
Successful Diagnosis of Intestinal Mycobacterium avium Complex Infection in a Kidney Transplant Recipient Using Nasogastric Aspirate Culture: A Case Report
Intestinal Mycobacterium avium complex (MAC) infections are rare and can be challenging to diagnose. We describe a case of intestinal MAC infection in a kidney transplant recipient with 5 months of unexplained weight loss and abdominal pain who developed intestinal obstruction. Esophagoduodenoscopy with biopsies was performed but was nondiagnostic. Intestinal MAC was diagnosed via nasogastric aspirate culture results. The patient's symptoms rapidly improved after initiation of appropriate treatment, but he later died of aspiration pneumonia and candidemia
CCL2 and CCR2 regulate pain-related behaviour and early gene expression in post-traumatic murine osteoarthritis but contribute little to chondropathy
SummaryObjectiveThe role of inflammation in structural and symptomatic osteoarthritis (OA) remains unclear. One key mediator of inflammation is the chemokine CCL2, primarily responsible for attracting monocytes to sites of injury. We investigated the role of CCL2 and its receptor CCR2 in experimental OA.DesignOA was induced in 10 weeks old male wild type (WT), Ccl2−/− and Ccr2−/− mice, by destabilisation of the medial meniscus (DMM). RNA was extracted from whole joints at 6 h and 7 days post-surgery and examined by reverse transcription polymerase chain reaction (RT-PCR). Gene expression changes between naïve and DMM-operated mice were compared. Chondropathy scores, from mice at 8, 12, 16 and 20 weeks post DMM were calculated using modified Osteoarthritis Research Society International (OARSI) grading systems. Changes in hind paw weight distribution, as a measure of pain, were assessed by Linton incapacitance.ResultsAbsence of CCL2 strongly suppressed (>90%) selective inflammatory response genes in the joint 6 h post DMM, including arginase 1, prostaglandin synthase 2, nitric oxide synthase 2 and inhibin A. IL6, MMP3 and tissue inhibitor of metalloproteinase 1 were also significantly suppressed. Similar trends were also observed in the absence of CCR2. A lower average chondropathy score was observed in both Ccl2−/− and Ccr2−/− mice at 12, 16 and 20 weeks post DMM compared with WT mice, but this was only statistically significant at 20 weeks in Ccr2−/− mice. Pain-related behaviour in Ccl2−/− and Ccr2−/− mice post DMM was delayed in onset.ConclusionThe CCL2/CCR2 axis plays an important role in the development of pain in murine OA, but contributes little to cartilage damage
Optimization of carboxymethyl cellulose-gum Arab-based hydrogel beads for anticancer drugs delivery
Response surface methodology was successfully utilized to optimize the amounts of carboxymethyl cellulose (CMC) and gum Arab (GA) to fabricate hydrogel beads for the delivery of anticancer drugs. Drug encapsulation efficiency process (%DEE) and cumulative release (%R8h) of hydrogel beads were investigated with different amounts of CMC and GA with Fe (III) cross-linker. The numerical validation resulted in an optimized nanocomposite of CMC (99.61 mg) and GA (77.84 mg) with a DEE of 55.70 ± 2.15 % and R8h of 44.78 ± 0.27 %. The characterization approaches indicated the successful formation of this nanocomposite. The swelling behavior of the beads was triggered by pH change, and the drug release profile showed prolonged sustainable release that followed the Higuchi model with a non-Fickian mechanism. This nanocomposite could be a promising nanocarrier for drug loading and its controlled delivery
Confirmation of Anomalous Dynamical Arrest in attractive colloids: a molecular dynamics study
Previous theoretical, along with early simulation and experimental, studies
have indicated that particles with a short-ranged attraction exhibit a range of
new dynamical arrest phenomena. These include very pronounced reentrance in the
dynamical arrest curve, a logarithmic singularity in the density correlation
functions, and the existence of `attractive' and `repulsive' glasses. Here we
carry out extensive molecular dynamics calculations on dense systems
interacting via a square-well potential. This is one of the simplest systems
with the required properties, and may be regarded as canonical for interpreting
the phase diagram, and now also the dynamical arrest. We confirm the
theoretical predictions for re-entrance, logarithmic singularity, and give the
first direct evidence of the coexistence, independent of theory, of the two
coexisting glasses. We now regard the previous predictions of these phenomena
as having been established.Comment: 15 pages,15 figures; submitted to Phys. Rev.
Pseudocapacitive performance of phenothiazine functionalized graphene aerogel
This study utilizes light adsorbing molecule, phenothiazine (PTZ) to reduce graphene oxide (GO) and functionalize into PTZ-rGO aerogel (PTZ-rGO). The UV excited PTZ reduces GO via electron transfer while PTZ is simultaneously oxidized and functionalized onto rGO to produce PTZ-rGO aerogel. The optimum incorporation of PTZ on rGO sheets renders good electrochemical active surface area of 495.71 m2 g−1 and enhances the diffusion behavior up to 41.92%. This pseudocapacitive effect and the excellent surface property provide promising charge storage results of 235.5 F g−1 at 0.5 A g−1. Furthermore, the stable charge-discharge cycles with 92% capacitance retention after 10,000 cycles render it an excellent electrode material for supercapacitor fabrication
Charged rotating dilaton black branes in AdS universe
We present the metric for the -dimensional charged rotating dilaton
black branes with cylindrical or toroidal horizons in the background of anti-de
Sitter spacetime. We find the suitable counterterm which removes the
divergences of the action in the presence of the dilaton potential in all
higher dimensions. We plot the Penrose diagrams of the spacetime and reveal
that the spacetime geometry crucially modifies in the presence of the dilaton
field. The conserved and thermodynamic quantities of the black branes are also
computed.Comment: 13 pages, 3 figures, to appear in Gen. Relat. Gravi
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