Spontaneous Interlayer Charge Transfer near the Magnetic Quantum Limit

Experiments reveal that a confined electron system with two equally-populated layers at zero magnetic field can spontaneously break this symmetry through an interlayer charge transfer near the magnetic quantum limit. New fractional quantum Hall states at unusual total filling factors such as \nu = 11/15 (= 1/3 + 2/5) stabilize as signatures that the system deforms itself, at substantial electrostatic energy cost, in order to gain crucial correlation energy by "locking in" separate incompressible liquid phases at unequal fillings in the two layers (e.g., layered 1/3 and 2/5 states in the case of \nu = 11/15).Comment: 4 pages, 4 figures (1 color) included in text. Related papers at http://www.ee.princeton.edu/~hari/papers.htm

A simple interpretation of quantum mirages

In an interesting new experiment the electronic structure of a magnetic atom adsorbed on the surface of Cu(111), observed by STM, was projected into a remote location on the same surface. The purpose of the present paper is to interpret this experiment with a model Hamiltonian, using ellipses of the size of the experimental ones, containing about 2300 atoms. The charge distribution for the different wavefunctions is analyzed, in particular, for those with energy close to the Fermi energy of copper Ef. Some of them show two symmetric maxima located on the principal axis of the ellipse but not necessarily at the foci. If a Co atom is adsorbed at the site where the wavefunction with energy $E_F$ has a maximum and the interaction is small, the main effect of the adsorbed atom will be to split this particular wavefunction in two. The total charge density will remain the same but the local density of states will present a dip at Ef at any site where the charge density is large enough. We relate the presence of this dip to the observation of quantum mirages. Our interpretation suggests that other sites, apart from the foci of the ellipses, can be used for projecting atomic images and also indicates the conditions for other non magnetic adsorbates to produce mirages.Comment: 3 pages, 3 Fig

The Effect of Spin Splitting on the Metallic Behavior of a Two-Dimensional System

Experiments on a constant-density two-dimensional hole system in a GaAs quantum well reveal that the metallic behavior observed in the zero-magnetic-field temperature dependence of the resistivity depends on the symmetry of the confinement potential and the resulting spin-splitting of the valence band

Addition of rice bran arabinoxylan to curcumin therapy may be of benefit to patients with early-stage B-cell lymphoid malignancies (monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, or stage 0/1 chronic lymphocytic leukemia): a preliminary clinical study

Hypothesis. Prior studies on patients with early B-cell lymphoid malignancies suggest that early intervention with curcumin may lead to delay in progressive disease and prolonged survival. These patients are characterized by increased susceptibility to infections. Rice bran arabinoxylan (Ribraxx) has been shown to have immunostimulatory, anti-inflammatory, and proapoptotic effects. We postulated that addition of Ribraxx to curcumin therapy may be of benefit. Study design. Monoclonal gammopathy of undetermined significance (MGUS)/smoldering multiple myeloma (SMM) or stage 0/1 chronic lymphocytic leukemia (CLL) patients who had been on oral curcumin therapy for a period of 6 months or more were administered both curcumin (as Curcuforte) and Ribraxx. Methods. Ten MGUS/SMM patients and 10 patients with stage 0/1 CLL were administered 6 g of curcumin and 2 g Ribraxx daily. Blood samples were collected at baseline and at 2-month intervals for a period of 6 months, and various markers were monitored. MGUS/SMM patients included full blood count (FBC); paraprotein; free light chains/ratio; C-reactive protein (CRP)and erythrocyte sedimentation rate (ESR); B2 microglobulin and immunological markers. Markers monitored for stage 0/1 CLL were FBC, CRP and ESR, and immunological markers. Results. Of 10 MGUS/SMM patients,5 (50%) were neutropenic at baseline, and the Curcuforte/Ribraxx combination therapy showed an increased neutrophil count, varying between 10% and 90% among 8 of the 10 (80%) MGUS/SMM patients. An additional benefit of the combination therapy was the potent effect in reducing the raised ESR in 4 (44%) of the MGUS/SMM patients. Conclusion. Addition of Ribraxx to curcumin therapy may be of benefit to patients with early-stage B-cell lymphoid malignancies

Scattering Theory of Kondo Mirages and Observation of Single Kondo Atom Phase Shift

We explain the origin of the Kondo mirage seen in recent quantum corral Scanning Tunneling Microscope (STM) experiments with a scattering theory of electrons on the surfaces of metals. Our theory combined with experimental data provides the first direct observation of a single Kondo atom phase shift. The Kondo mirage at the empty focus of an elliptical quantum corral is shown to arise from multiple electron bounces off the walls of the corral in a manner analagous to the formation of a real image in optics. We demonstrate our theory with direct quantitive comparision to experimental data.Comment: 13 pages; significant clarifications of metho

Projecting the Kondo Effect: Theory of the Quantum Mirage

A microscopic theory is developed for the projection (quantum mirage) of the Kondo resonance from one focus of an elliptic quantum corral to the other focus. The quantum mirage is shown to be independent of the size and the shape of the ellipse, and experiences \lambda_F/4 oscillations (\lambda_F is the surface-band Fermi wavelength) with an increasing semimajor axis length. We predict an oscillatory behavior of the mirage as a function of a weak magnetic field applied perpendicular to the sample.Comment: 4 pages 2 figures include

Effect of the Ginger Derivative, 6-Shogaol, on Ferritin Levels in Patients With Low to Intermediate-1-Risk Myelodysplastic Syndrome-A Small, Investigative Study

Background: Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal stem cell disorders characterized by dysplastic and ineffective hematopoiesis and peripheral cytopenias. Elevated serum ferritin (SF) is often observed in nontransfused, lower risk MDS. It has been reported that ineffective erythropoiesis enhances iron absorption in MDS through downregulation of hepcidin and its prohormones such that SF rises. Aim: To determine the effect of 6-shogaol, a dehydration derivative of ginger, known to have hepatoprotective and chemotherapeutic activity, on 6 early-stage, transfusion-independent patients with MDS, 3 of whom had raised levels of SF. Method: Six patients with MDS with low or intermediate-1 subtypes, as defined by the International Prognostic Scoring System (IPSS), were recruited into the study and were administered 1 gel capsule daily containing 20 mg ginger extract standardized for 20% 6-shogaol. Blood and urine samples were collected and various markers monitored at regular intervals. Results: 6-shogaol caused a decrease in SF levels in 3 of 6 patients with early MDS (50%) whose SF levels were elevated at the start of the study. Our findings suggest upregulation of hepcidin and its prohormones, possibly through an improvement in liver function. Discussion: In light of the encouraging results in this small, investigative study, we are planning a larger study to confirm the beneficial effect of 6-shogaol in patients with raised ferritin levels due to ineffective erythropoiesis