4,099 research outputs found
Unbroken supersymmetry in the Aharonov-Casher effect
We consider the problem of the bound states of a spin 1/2 chargless particle
in a given Aharonov-Casher configuration. To this end we recast the description
of the system in a supersymmetric form. Then the basic physical requirements
for unbroken supersymmetry are established. We comment on the possibility of
neutron confinement in this system
Neutron Acceleration in Uniform Electromagnetic Fields
The question as to whether neutron acceleration can occur in uniform
electromagnetic fields is examined. Although such an effect has been predicted
using the canonical equations of motion some doubt has been raised recently as
to whether it is in principle observable for a spin 1/2 particle. To resolve
this issue a gedanken experiment is proposed and analyzed using a wave packet
construction for the neutron beam. By allowing arbitrary orientation for the
neutron spin as well as for the electric and magnetic fields a non vanishing
acceleration of the center of the neutron wave packet is found which confirms
the predictions of the canonical formalism.Comment: 11 page
pygfunction 2.2 : New features and improvements in accuracy and computational efficiency
Recent improvements to pygfunction, an open-source tool for the calculation of ??-functions, are presented. The latest version 2.2 enables the calculation of ??-functions for fields containing inclined boreholes. Various changes introduced in versions 2.0, 2.1 and 2.2 have led to significant decreases in calculation time and memory usage while increasing the accuracy of calculations. This allows the calculation of ??-functions of fields comprised of thousands of boreholes. A development roadmap towards a version 3.0 is presented. This future release will increase the scope of the tool to consider additional physical processes
Oligonucleotide analogues as modulators of the expression and function of noncoding RNAs (ncRNAs) : Emerging therapeutics applications
ncRNAs are emerging as key regulators of physiological and pathological processes and therefore have been identified as pharmacological targets and as markers for some diseases. Oligonucleotide analogues represent so far the most widely employed tool for the modulation of the expression of ncRNAs. In this perspective we briefly describe most of the known classes of ncRNAs and then we discuss the design and the applications of oligonucleotide analogues for their targeting. The effects of modifications of the chemical structure of the oligonucleotides on properties such as the binding affinity toward targets and off targets, and the stability to degradation and their biological effects (when known) are discussed. Examples of molecules currently used in clinical trials are also reported
Bound states of neutral particles in external electric fields
Neutral fermions of spin with magnetic moment can interact with
electromagnetic fields through nonminimal coupling. The Dirac--Pauli equation
for such a fermion coupled to a spherically symmetric or central electric field
can be reduced to two simultaneous ordinary differential equations by
separation of variables in spherical coordinates. For a wide variety of central
electric fields, bound-state solutions of critical energy values can be found
analytically. The degeneracy of these energy levels turns out to be numerably
infinite. This reveals the possibility of condensing infinitely many fermions
into a single energy level. For radially constant and radially linear electric
fields, the system of ordinary differential equations can be completely solved,
and all bound-state solutions are obtained in closed forms. The radially
constant field supports scattering solutions as well. For radially linear
fields, more energy levels (in addition to the critical one) are infinitely
degenerate. The simultaneous presence of central magnetic and electric fields
is discussed.Comment: REVTeX, 14 pages, no figur
The correct prednisone starting dose in polymyalgia rheumatica is related to body weight but not to disease severity
<p>Abstract</p> <p>Background</p> <p>the mainstay of treatment of polymyalgia rheumatica (PMR) is oral glucocorticoids, but randomized controlled trials of treatment are lacking. As a result, there is no evidence from controlled studies on the efficacy of different initial doses or glucocorticoid tapering. The aim of this study is to test if 12.5 mg prednisone/day is an adequate starting dose in PMR and to evaluate clinical predictors of drug response.</p> <p>Methods</p> <p>60 consecutive PMR patients were treated with a starting dose of 12,5 mg/day prednisone. Clinical, laboratory, and, in a subset of 25 patients, ultrasonographic features were recorded as possible predictors of response to prednisone. Remission was defined as disappearance of at least 75% of the signs and symptoms of PMR and normalization of ESR and CRP within the first month, a scenario allowing steroid tapering.</p> <p>Results</p> <p>47/60 (78.3%) patients responded to 12.5 mg of prednisone after a mean interval of 6.6 ± 5.2 days. In univariate analysis, body weight and gender discriminated the two groups. In multivariate analysis, the only factor predicting a good response was low weight (p = 0.004); the higher response rate observed in women was explained by their lower weight. The mean prednisone dose per kg in the responders was 0.19 ± 0.03 mg in comparison with 0.16 ± 0.03 mg for non responders (p = 0.007).</p> <p>Conclusions</p> <p>12.5 mg prednisone is a sufficient starting dose in ¾ of PMR patients. The main factor driving response to prednisone in PMR was weight, a finding that could help in the clinical care of PMR patients and in designing prospective studies of treatment.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01169597">NCT01169597</a></p
Plantar pain is not always fasciitis
The case is described of a patient with chronic plantar pain, diagnosed as fasciitis, which was not improved by conventional treatment. Magnetic resonance imaging revealed flexor hallucis longus tenosynovitis, which improved after local glucocorticoid injection
Can early switch to rituximab-bendamustine in a patient with follicular non-Hodgkin lymphoma progressing during R-CHOP be considered frontline treatment?: A case report
RATIONALE: Follicular non-Hodgkin lymphoma (fNHL) is a neoplasm characterized by an indolent course and chemosensitivity, but also by disease recurrence. Bendamustine is often used as frontline treatment or second line. HEADING DIAGNOSIS:: fNHL. PATIENT CONCERNS: A 63-year-old Caucasian male with diagnosis of fNHL lymphoma underwent to cyclophosphamide, doxorubicin, vincristine, and prednisone associated with rituximab chemoimmunotherapy, during which interim reevaluation showed progressive disease and severe toxicity. INTERVENTIONS: Early switch to rituximab-bendamustine. OUTCOMES: This regimen was well tolerated, patient compliance was optimal, there were no delays in administration and no infectious episodes. An interim reevaluation after 3 courses revealed that the patient was fit, the blood cell count was normal, and lymphadenopathies and nocturnal sweating had completely regressed. Of note, the PET/CT scan did not show fluorodeoxyglucose pathological uptake, clearly confirming disease regression. LESSONS: Early switching to a bendamustine-rituximab-based scheme, even during conventional chemotherapy, decreases toxicity and reduces the risk of treatment interruption or delay, with favorable effects on overall response and prognosis
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