496 research outputs found
How should we treat chronic daily headache when conservative measures fail?
For the purposes of this review, we considered conservative measures to include such therapies as nonsteroidal anti-inflammatory drugs (NSAIDs), physical therapy, and acetaminophen with codeine. Amitriptyline is the best-supported option for the treatment of chronic daily headaches for those patients who have not been treated by conservative measures (strength of recommendation [SOR]: A, based on a metaanalysis of randomized controlled trials [RCTs]). For patients who overuse symptomatic headache medications, medication withdrawal is effective (SOR: B, based on a systematic review of cohort and case-control studies). Additional therapies include other tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), and prophylactic treatments for migraine (SOR: B)
Intertwining relations of non-stationary Schr\"odinger operators
General first- and higher-order intertwining relations between non-stationary
one-dimensional Schr\"odinger operators are introduced. For the first-order
case it is shown that the intertwining relations imply some hidden symmetry
which in turn results in a -separation of variables. The Fokker-Planck and
diffusion equation are briefly considered. Second-order intertwining operators
are also discussed within a general approach. However, due to its complicated
structure only particular solutions are given in some detail.Comment: 18 pages, LaTeX20
Antiproton-Hydrogen annihilation at sub-kelvin temperatures
The main properties of the interaction of ultra low-energy antiprotons ( a.u.) with atomic hydrogen are established. They include the
elastic and inelastic cross sections and Protonium (Pn) formation spectrum. The
inverse Auger process () is taken into account in the
framework of an unitary coupled-channels model. The annihilation cross-section
is found to be several times smaller than the predictions made by the black
sphere absorption models. A family of nearthreshold metastable
states is predicited. The dependence of Protonium formation probability on the
position of such nearthreshold S-matrix singularities is analysed. An
estimation for the annihilation cross section is obtained.Comment: latex.tar.gz file, 22 pages, 9 figure
Quantum metastability in a class of moving potentials
In this paper we consider quantum metastability in a class of moving
potentials introduced by Berry and Klein. Potential in this class has its
height and width scaled in a specific way so that it can be transformed into a
stationary one. In deriving the non-decay probability of the system, we argue
that the appropriate technique to use is the less known method of scattering
states. This method is illustrated through two examples, namely, a moving
delta-potential and a moving barrier potential. For expanding potentials, one
finds that a small but finite non-decay probability persists at large times.
Generalization to scaling potentials of arbitrary shape is briefly indicated.Comment: 10 pages, 1 figure
Sporadic renal cell carcinoma in young and elderly patients: are there different clinicopathological features and disease specific survival rates?
BACKGROUND: Sporadic renal cell carcinoma (RCC) is rare in young adults. In the present retrospective study we reviewed clinicopathological features and disease specific survival rates in young patients (â€45 years) with RCC and compared them to old patients (â„75 years) with RCC. METHODS: Between 1992 and 2005 a total of 1042 patients were treated for RCC at our institution. We found 70 patients 45 years or younger (YP) and 150 patients 75 years or older (OP) at time of diagnosis. There were no differences in therapeutical approaches between both groups. Clinical and biologic parameters at diagnosis were compared and subjected to uni- and multivariate analysis to study cancer specific survival and progression rate. Mean postoperative follow-up in both groups was 50.1 months. RESULTS: Mean age was 39 years in YP and 80 years in OP, respectively. YP demonstrated significantly lower stage (pT1-pT2 N0 M0, p = 0.03), lower tumor grade (p = 0.01) and higher male-to-female ratio (p < 0.001). The rate of lymph node metastases or distant metastatic disease at presentation did not differ significantly between both groups. In multivariate analysis young age was independently associated with a higher 5-year cancer specific survival (95.2% vs. 72.3%, p = 0.009) and a lower 5-year progression rate (11.3% vs. 42.5%, p = 0.002). CONCLUSION: Sporadic RCC in young patients have lower tumor stages and grades and a better outcome compared to elderly. Ageâ€45 years was an independent prognostic factor for survival and progression
Free Energy of an Inhomogeneous Superconductor: a Wave Function Approach
A new method for calculating the free energy of an inhomogeneous
superconductor is presented. This method is based on the quasiclassical limit
(or Andreev approximation) of the Bogoliubov-de Gennes (or wave function)
formulation of the theory of weakly coupled superconductors. The method is
applicable to any pure bulk superconductor described by a pair potential with
arbitrary spatial dependence, in the presence of supercurrents and external
magnetic field. We find that both the local density of states and the free
energy density of an inhomogeneous superconductor can be expressed in terms of
the diagonal resolvent of the corresponding Andreev Hamiltonian, resolvent
which obeys the so-called Gelfand-Dikii equation. Also, the connection between
the well known Eilenberger equation for the quasiclassical Green's function and
the less known Gelfand-Dikii equation for the diagonal resolvent of the Andreev
Hamiltonian is established. These results are used to construct a general
algorithm for calculating the (gauge invariant) gradient expansion of the free
energy density of an inhomogeneous superconductor at arbitrary temperatures.Comment: REVTeX, 28 page
Coalescing Binary Neutron Stars
Coalescing compact binaries with neutron star or black hole components
provide the most promising sources of gravitational radiation for detection by
the LIGO/VIRGO/GEO/TAMA laser interferometers now under construction. This fact
has motivated several different theoretical studies of the inspiral and
hydrodynamic merging of compact binaries. Analytic analyses of the inspiral
waveforms have been performed in the Post-Newtonian approximation. Analytic and
numerical treatments of the coalescence waveforms from binary neutron stars
have been performed using Newtonian hydrodynamics and the quadrupole radiation
approximation. Numerical simulations of coalescing black hole and neutron star
binaries are also underway in full general relativity. Recent results from each
of these approaches will be described and their virtues and limitations
summarized.Comment: Invited Topical Review paper to appear in Classical and Quantum
Gravity, 35 pages, including 5 figure
Recent Advances in Graph Partitioning
We survey recent trends in practical algorithms for balanced graph
partitioning together with applications and future research directions
Linking Proteins to Signaling Pathways for Experiment Design and Evaluation
Biomedical experimental work often focuses on altering the functions of selected proteins. These changes can hit signaling pathways, and can therefore unexpectedly and non-specifically affect cellular processes. We propose PathwayLinker, an online tool that can provide a first estimate of the possible signaling effects of such changes, e.g., drug or microRNA treatments. PathwayLinker minimizes the users' efforts by integrating protein-protein interaction and signaling pathway data from several sources with statistical significance tests and clear visualization. We demonstrate through three case studies that the developed tool can point out unexpected signaling bias in normal laboratory experiments and identify likely novel signaling proteins among the interactors of known drug targets. In our first case study we show that knockdown of the Caenorhabditis elegans gene cdc-25.1 (meant to avoid progeny) may globally affect the signaling system and unexpectedly bias experiments. In the second case study we evaluate the loss-of-function phenotypes of a less known C. elegans gene to predict its function. In the third case study we analyze GJA1, an anti-cancer drug target protein in human, and predict for this protein novel signaling pathway memberships, which may be sources of side effects. Compared to similar services, a major advantage of PathwayLinker is that it drastically reduces the necessary amount of manual literature searches and can be used without a computational background. PathwayLinker is available at http://PathwayLinker.org. Detailed documentation and source code are available at the website
Electronic and paper versions of a faces pain intensity scale: concordance and preference in hospitalized children
<p>Abstract</p> <p>Background</p> <p>Assessment of pain in children is an important aspect of pain management and can be performed by observational methods or by self-assessment. The Faces Pain Scale-Revised (FPS-R) is a self-report tool which has strong positive correlations with other well established self-report pain intensity measures. It has been recommended for measuring pain intensity in school-aged children (4 years and older). The objective of this study is to compare the concordance and the preference for two versions, electronic and paper, of the FPS-R, and to determine whether an electronic version of the FPS-R can be used by children aged 4 and older.</p> <p>Methods</p> <p>The study is an observational, multicenter, randomized, cross-over, controlled, open trial. Medical and surgical patients in two pediatric hospitals (N = 202, age 4-12 years, mean age 8.3 years, 58% male) provided self-reports of their present pain using the FPS-R on a personal digital assistant (PDA) and on a paper version. Paper and electronic versions of the FPS-R were administered by a nurse in a randomized order: half the patients were given the PDA version first and the other half the paper version first. The time between the administrations was planned to be less than 30 minutes but not simultaneous. Two hundred and thirty-seven patients were enrolled; 35 were excluded from analysis because of misunderstanding of instructions or abnormal time between the two assessments.</p> <p>Results</p> <p>Final population for analysis comprised 202 children. The overall weighted Kappa was 0.846 (95%CI: 0.795; 0.896) and the Spearman correlation between scores on the two versions was r<sub>s </sub>= 0.911 (p < 0.0001). The mean difference of pain scores was less than 0.1 out of 10, which was neither statistically nor clinically significant; 83.2% of children chose the same face on both versions of the FPS-R. Preference was not modified by order, sex, age, hospitalization unit (medical or surgical units), or previous analgesics. The PDA was preferred by 87.4% of the children who expressed a preference.</p> <p>Conclusion</p> <p>The electronic version of the FPS-R can be recommended for use with children aged 4 to 12, either in clinical trials or in hospitals to monitor pain intensity.</p
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