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What is the best management for patients with evidence of asymptomatic ischemia on exercise stress testing?
(Family Physicians Inquiries Network, 2007)
Patients with intermediate- or high-risk Duke Treadmill Score (DTS) on exercise stress testing (EST) should undergo myocardial perfusion imaging or exercise echocardiography, especially if they have abnormal values of ...
What's the best diagnostic evaluation of night sweats?
(Family Physicians Inquiries Network, 2007)
There is no single best evidence-based approach to the diagnostic evaluation of night sweats, given the limited number of studies on the subject. A detailed history, however, does appear to be the most important initial ...
What evaluation is best for an isolated, enlarged cervical lymph node?
(Family Physicians Inquiries Network, 2007)
The evaluation and follow-up of an isolated, enlarged cervical lymph node is determined by the presence of inflammation, duration, size, and associated symptoms. For patients with inflammatory symptoms (ie, fever, pain, ...
What are the best treatments for herpes labialis?
(Family Physicians Inquiries Network, 2007)
There are 3: valacyclovir, acyclovir, and topical penciclovir. Valacyclovir, 2g twice in 1 day taken during the prodromal stage of herpes labialis, reduces the episode duration and time to healing. Acyclovir, 400 mg, taken ...
Is DEET safe for children?
(Family Physicians Inquiries Network, 2005)
Reported evidence suggests that DEET use is safe for children older than 2 months, with only very rare incidence of major adverse effects (strength of recommendation [SOR]: C). Typically, a topical concentration between ...
Who should receive vertebroplasty?
(Family Physicians Inquiries Network, 2006)
Percutaneous vertebroplasty has been used to treat aggressive vertebral hemangiomas, osteoporotic vertebral compression fractures, and vertebral lesions from metastatic disease or myeloma. Consider it for patients with ...
Ubiquity of simplices in subsets of vector spaces over finite fields
(2007)
We prove that a sufficiently large subset of the $d$-dimensional vector space over a finite field with $q$ elements, $ {\Bbb F}_q^d$, contains a copy of every $k$-simplex. Fourier analytic methods, Kloosterman sums, and ...
Sums and products in finite fields: an integral geometric viewpoint
(2007)
We prove that if $A \subset {\Bbb F}_q$ is such that $$|A|>q^{{1/2}+\frac{1}{2d}},$$ then $${\Bbb F}_q^{*} \subset dA^2=A^2+...+A^2 d \text{times},$$ where $$A^2=\{a \cdot a': a,a' \in A\},$$ and where ${\Bbb F}_q^{*}$ ...
Time-dependent density-functional theory beyond the adiabatic approximation: Insights from a two-electron model system
(American Institute of Physics, 2006)
Most applications of time-dependent density-functional theory (TDDFT) use the adiabatic local-density approximation (ALDA) for the dynamical exchange-correlation potential Vxc(r,t). An exact (i.e., nonadiabatic) extension ...
Complex pore spaces create record-breaking methane storage system for natural-gas vehicles
(American Institute of Physics, 2007)
It has been proposed that nearly space-filling networks of nanopores in biocarbon may provide a “sponge” for lowpressure,
high-capacity storage of methane CH4 for advanced transportation.1 Such pores, a few molecular ...
Transport and optical conductivity in dilute magnetic semiconductors
(Institute of Physics, 2009)
A theory of transport in spin and charge disordered media is developed, with a particular emphasis on dilute magnetic semiconductors. The approach is based on the equation of motion for the current-current response function ...
Enhanced hydrogen adsorption in boron substituted carbon nanospaces
(American Institute of Physics, 2009)
Activated carbons are one of promising groups of materials for reversible storage of hydrogen by physisorption. However, the heat of hydrogen adsorption in such materials is relatively low, in the range of about 4-8 kJ/mol, ...
Nonuniqueness in spin-density-functional theory on lattices
(American Physical Society, 2005)
In electronic many-particle systems, the mapping between densities and spin magnetizations, {n(r),m(r)}, and potentials and magnetic fields, {v(r),B(r)}, is known to be nonunique, which has fundamental and practical ...
Real-Time Electron Dynamics with Exact-Exchange Time-Dependent Density-Functional Theory
(American Physical Society, 2008)
The exact exchange potential in time- dependent density-functional theory is defined as an orbital functional through the time-dependent optimized effective potential (TDOEP) method. We numerically solve the TDOEP integral ...
Intersubband spin-orbit coupling and spin splitting in symmetric quantum wells
(arXiv, 2007)
In semiconductors with inversion asymmetry, spin-orbit coupling gives rise to the well-known Dresselhaus and Rashba effects. If one considers quantum wells with two or more conduction subbands, an additional, intersubband-induced ...
Spin-Hall effect and spin-Coulomb drag in doped semiconductors
(American Institute of Physics, 2009)
In this review, we describe in detail two important spin-transport phenomena: the extrinsic spin-Hall effect (coming from spin-orbit interactions between electrons and impurities) and the spin-Coulomb drag. The interplay ...
Linear response of doped graphene sheets to vector potentials
(American Physical Society, 2009)
A two-dimensional gas of massless Dirac fermions (MDFs) is a very useful model to describe low-energy electrons in monolayer graphene. Because the MDF current operator is directly proportional to the (sublattice) pseudospin ...
Liquid crystalline states for two-dimensional electrons in strong magnetic fields
(American Physical Society, 2004)
Based on the Kosterlitz-Thouless-Halperin-Nelson-Young theory of two-dimensional melting and the analogy between Laughlin states and the two-dimensional one-component plasma, we investigate the possibility of liquid ...
Magnetic and Orbital Order in LaMnO3 under Uniaxial Strain: A Model Study
(arXiv, 2009)
The effect of uniaxial strain on electronic structure and magnetism in LaMnO3 is studied from a
model Hamiltonian that illustrates the competition between the Jahn-Teller, super exchange, and
double exchange interactions. ...
Polar catastrophe, electron leakage, and magnetic ordering at the LaMnO3/SrMnO3 interface
(arXiv, 2009)
Electronic reconstruction at the polar interface LaMnO3/SrMnO3 (LMO/SMO) (100) resulting
from the polar catastrophe is studied from a model Hamiltonian that includes the double and super exchange interactions, the Madelung ...