Spontaneous Magnetization and Electron Momentum Density in 3D Quantum Dots

We discuss an exactly solvable model Hamiltonian for describing the interacting electron gas in a quantum dot. Results for a spherical square well confining potential are presented. The ground state is found to exhibit striking oscillations in spin polarization with dot radius at a fixed electron density. These oscillations are shown to induce characteristic signatures in the momentum density of the electron gas, providing a novel route for direct experimental observation of the dot magnetization via spectroscopies sensitive to the electron momentum density.Comment: 5 pages (Revtex4), 4 (eps) figure

Semiclassical theory of transport in a random magnetic field

We study the semiclassical kinetics of 2D fermions in a smoothly varying magnetic field $B({\bf r})$. The nature of the transport depends crucially on both the strength $B_0$ of the random component of $B({\bf r})$ and its mean value $\bar{B}$. For $\bar{B}=0$, the governing parameter is $\alpha=d/R_0$, where $d$ is the correlation length of disorder and $R_0$ is the Larmor radius in the field $B_0$. While for $\alpha\ll 1$ the Drude theory applies, at $\alpha\gg 1$ most particles drift adiabatically along closed contours and are localized in the adiabatic approximation. The conductivity is then determined by a special class of trajectories, the "snake states", which percolate by scattering at the saddle points of $B({\bf r})$ where the adiabaticity of their motion breaks down. The external field also suppresses the diffusion by creating a percolation network of drifting cyclotron orbits. This kind of percolation is due only to a weak violation of the adiabaticity of the cyclotron rotation, yielding an exponential drop of the conductivity at large $\bar{B}$. In the regime $\alpha\gg 1$ the crossover between the snake-state percolation and the percolation of the drift orbits with increasing $\bar{B}$ has the character of a phase transition (localization of snake states) smeared exponentially weakly by non-adiabatic effects. The ac conductivity also reflects the dynamical properties of particles moving on the fractal percolation network. In particular, it has a sharp kink at zero frequency and falls off exponentially at higher frequencies. We also discuss the nature of the quantum magnetooscillations. Detailed numerical studies confirm the analytical findings. The shape of the magnetoresistivity at $\alpha\sim 1$ is in good agreement with experimental data in the FQHE regime near $\nu=1/2$.Comment: 22 pages REVTEX, 14 figure

Safety assessment of essential medicines for elderly people: a bibliographic survey

Certain medicines are considered potentially inappropriate (PIM) for elderly people as they increase the risk of adverse drug events (ADE) and because safer alternative therapies are available on the market. In this context, in order to identify the instruments that assess the quality of medical prescriptions for elderly and to determine which drugs are considered PIM, a bibliographic survey was conducted in PUBMED, LILACS and PAHO databases, in February and March/2010. The search strategy included the use of health descriptors and a manual search in the references cited by selected papers. During the period of data collection, 15 instruments were identified. In 2012, with the publication of the update of Beers criteria, this instrument was included in the study. We identified 163 PIM of 25 therapeutic classes, of which 125 (76.7%) are marketed in Brazil. Of these, 31 (24.8%) are essential medicines (RENAME 2012), of which 13 have safer therapeutic equivalents and 19 (15.2%) are over-the-counter drugs. Data suggest the need for inclusion of safer alternatives for the elderly in the national list of essential medicines and the pharmaceutical care for early detection of ADE in this age group, in order to contribute to the safe use of medicines

Voorstel voor gestandaardiseerde rapportage van economische evaluaties

Contains fulltext : 25221___.PDF (publisher's version ) (Open Access

Postnatal cranial ultrasonographic findings in feto-fetal transfusion syndrome.

Item does not contain fulltextOur objective was a retrospective evaluation of cranial US in survivors of twin pregnancy with feto-fetal transfusion syndrome (FFTS), with knowledge of prenatal treatment and neonatal/postnatal clinical data. In 18 pregnancies with FFTS (January 1996 to May 2000), pregnancy management and outcome, and neonatal clinical/neurological data and follow-up (age of 3-7 months) were documented when available. Postnatal cranial US abnormalities were differentiated in prenatal and peri/postnatal lesions, respectively, in "donor" and "recipient." The statistical analysis used was Mann Whitney U test and Fisher's exact test. Overall pregnancy survival rate was 19 of 36 (53%); mors in utero occurred in five twin members. Gestational age at birth was significantly lower in FFTS after laser coagulation (13 of 18; p<0.05). Initial (</=4 days of age) postnatal cranial US was abnormal in 13 of 27 cases: antenatal brain lesion in 9 of 13 patients (7 of 13 donors, 2 of 14 recipients); after treatment: antenatal hemorrhage ( n=6), hydrocephaly ( n=1), subependymal germinolysis ( n=1), lenticulostriatal vasculopathy ( n=1), evidence for brain atrophy ( n=2), cystic periventricular leukomalacia in<3 days ( n=1); peri/postnatal brain lesions in 4 of 13 patients (hemorrhage ( n=3), and periventricular leukomalacia ( n=1). Finally, an abnormal brain US was found in 18 patients. Twin pregnancies complicated with FFTS are high-risk pregnancies with antenatal and postnatal mortality and morbidity. In utero cranial hemorrhage dominated the antenatal brain insults; however, pregnancy survivors remain at risk for severe peripartal and/or postnatal brain insults

Introduction to the pharmacoeconomics of herbal medicines

Jing-Bao Nie. 2005. Behind the Silence: Chinese Voices on Abortion. Rowman & Littlefield: Lanham, Boulder, New York, Toronto and Oxford. 294 pages. ISBN 0 7425 2370

Reporting format for economic evaluation: part 1: Application to the Dutch Healthcare system

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