3,584 research outputs found
The ground state of a spin-1/2 neutral particle with anomalous magnetic moment in a Aharonov-Casher configuration
We determine the (bound) ground state of a spin 1/2 chargless particle with
anomalous magnetic moment in certain Aharonov-Casher configurations. 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 trapping in these systems
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
Supracricoid Partial Laryngectomy: Oncological and Functional Outcomes
Introduction In the present study, we have reviewed the outcomes of patients with supracricoid partial laryngectomy (SCPL) in our institution. Our results show that SCPL is a well-tolerated procedure with generally good functional outcomes for patients with advanced laryngeal cancer. Objective We analyzed the oncological and functional results of a cohort of 35 patients who had undergone SCPL, and we highlighted the complications, identified the overall and disease-free survivals, demonstrating that the reconstructive laryngectomy guarantees the oncological safety and reproducibility of the oncological results, preserving the laryngeal functions and promoting an improvement in the patient's quality of life, favoring communication and interpersonal relationships. Methods Between 2010 and 2018, 35 patients underwent SCPL for primary and recurrent laryngeal squamous cell carcinomas, and they were divided into two subgroups: in 16 cases, the cricohyoidoepiglottopexy according to the Mayer-Piquet technique was performed, while the remaining 19 cases were submitted to the cricohyoidopexy according to the Labayle technique. In addition to evaluating the oncological results of patients undergoing reconstructive laryngectomy, the present study also aimed to evaluate the functionality of the residual larynx and the quality of life. Results The overall and disease-free survivals were of 83% and 76.3% respectively. All patients were able to swallow. The nasogastric tube was removed after a mean period of 21.8 days (range: 14 to 28 days). The mean decannulation time was of 23.4 days after surgery (range: 15 to 36 days). Conclusion The curves for the overall and disease-free survivals show that SCPL can guarantee oncological safety comparable to that of total laryngectomies in diseases in the intermediate stage and in carefully-selected advanced stages
Noncommutative quantum mechanics and the Aharonov-Casher effect
In this work a new method is developed to investigate the Aharonov-Casher
effect in a noncommutative space. It is shown that the holonomy receives
non-trivial kinematical corrections.Comment: 8 pages, Plain Tex, to appear in Eur. Phys. J.
first isolation of acetovanillone and piceol from crinum buphanoides and crinum graminicola i verd amaryllidaceae
Screening of three native South African Amaryllidaceae bulbs, aimed at finding new metabolites for their promising biological activities, lead to the initial discovery of two interesting non-alkaloid compounds viz., acetovanillone 1 (also known as apocynin) and 4-hydroxyacetophenone 2 (also named piceol) isolated from Crinum buphonoides, while only the former was isolated from Crinum graminicola. This is the first time that acetovanillone 1 and piceol 2 were isolated from C. graminicola and C. buphanoides, respectively. Acetovanillone 1 was recently reported as a metabolite of Boophane disticha (L.f.), another South Africa Amaryllidacea species
Persistent spin and mass currents and Aharonov-Casher effect
Spin-orbit interaction produces persistent spin and mass currents in the ring
via the Aharonov-Casher effect. The experiment in phase, in which
this effect leads to the excitation of mass and spin supercurrent is proposed.Comment: 10 page
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
New Seleno-Glyconjugates for Nutraceutical Application
Oxidative stress is a disequilibrium redox condition that occurs due to high concentration of prooxidant
reactive species (RS) and, by comparison, a lower concentration of endogenous
antioxidants in the body.1 Oxidative stress, caused by RS, is involved into the genesis of different
pathologies such as inflammatory bowel disease, cardiovascular disease, Alzheimer’s disease,
diabetes and cancer.2 Nutraceuticals could be used to prevent oxidative stress as an additional health
benefit along with nutrition.1 The use of exogenous antioxidants can ameliorate this stressful
condition and restore the redox disequilibrium.3 Polyphenols have a potential health-promoting
effect, however, show a low bioavailability.4 For this reason, synthesis of organic seleniumcompounds
combined to (poly)phenolic compounds could increase the solubility and exert their
potential synergistic antioxidant effects.
The approach proposed consists of preparing the D-ribose derivative 1 to obtain the donor 2 then
employed to produce glycoconjugates containing well known (poly)phenols through a Mitsunobu
reaction.5
To assess the bioactivity of selenoglycoconjugates, DPPH and ABTS antiradical assays were
performed, while the effects on cell proliferation were preliminarily investigated on SH-SY5Y
cells. The phenol moiety greatly affected both the antiradical efficacy and the mitochondrial redox
activity. The glycoconjugates, especially at the highest tested concentrations, exhibited cytotoxic
effects lower than that of unconjugated phenolic compounds, underlining the mitigating impact of
selenosugar
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