21,316 research outputs found
A Levinson theorem for scattering from a Bose-Einstein condensate
A relation between the number of bound collective excitations of an atomic
Bose-Einstein condensate and the phase shift of elastically scattered atoms is
derived. Within the Bogoliubov model of a weakly interacting Bose gas this
relation is exact and generalises Levinson's theorem. Specific features of the
Bogoliubov model such as complex-energy and continuum bound states are
discussed and a numerical example is given.Comment: 4 pages, 3 figure
The crystal structure of high-pressure ammonia-water solids containing 15, 67, and 80 mol% ND3
Collisions of solitons and vortex rings in cylindrical Bose-Einstein condensates
Interactions of solitary waves in a cylindrically confined Bose-Einstein
condensate are investigated by simulating their head-on collisions. Slow vortex
rings and fast solitons are found to collide elastically contrary to the
situation in the three-dimensional homogeneous Bose gas. Strongly inelastic
collisions are absent for low density condensates but occur at higher densities
for intermediate velocities. The scattering behaviour is rationalised by use of
dispersion diagrams. During inelastic collisions, spherical shell-like
structures of low density are formed and they eventually decay into depletion
droplets with solitary wave features. The relation to similar shells observed
in a recent experiment [Ginsberg et al. Phys Rev. Lett. 94, 040403 (2005)] is
discussed
High pressure properties of planetary sulphate hydrates determined from interatomic potential calculations.
The Distance and Age of the SNR Kes 73 and AXP 1E 1841-045
We provide a new distance estimate to the supernova remnant (SNR) Kes 73 and
its associated anomalous X-ray pulsar (AXP) 1E 1841-045. 21 cm HI images and HI
absorption/ emission spectra from new VLA observations, and 13CO emission
spectra of Kes 73 and two adjacent compact HII regions (G27.276+0.148 and
G27.491+0.189) are analyzed. The HI images show prominent absorption features
associated with Kes 73 and the HII regions. The absorption appears up to the
tangent point velocity giving a lower distance limit to Kes 73 of 7.5 kpc,
which has previously been given as the upper limit. Also, G27.276+0.148 and
G27.491+0.189 are at the far kinematic distances of their radio recombination
line velocities. There is prominent HI emission in the range 80--90 km/s for
all three objects. The two HII regions show HI absorption at ~ 84 km/s, but
there is no absorption in the Kes 73 absorption spectrum. This implies an upper
distance limit of ~ 9.8 kpc to Kes 73. This corrected larger distance to Kes
73/ AXP 1E 1841-045 system leads to a refined age of the SNR of 500 to 1000 yr,
and a ~ 50% larger AXP X-ray luminosity.Comment: 10 pages, 2 figures, ApJ, dol:10.1086/"529120
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Efficacy and safety of DFN-11 (sumatriptan injection, 3 mg) in adults with episodic migraine: a multicenter, randomized, double-blind, placebo-controlled study.
BackgroundIn a previous randomized, double-blind, proof-of-concept study in rapidly escalating migraine, a 3 mg dose of subcutaneous sumatriptan (DFN-11) was associated with fewer and shorter triptan sensations than a 6 mg dose. The primary objective of the study was to assess the efficacy and safety of acute treatment with DFN-11 compared with placebo in episodic migraine.MethodsThis was a multicenter, randomized, double-blind, placebo-controlled efficacy and safety study of DFN-11 in the acute treatment of adults with episodic migraine (study RESTOR). The primary endpoint was the proportion of subjects taking DFN-11 who were pain free at 2 h postdose in the double-blind period compared with placebo. Secondary endpoints included earlier postdose timepoints, assessments of pain relief and subjects' freedom from their most bothersome symptom (MBS) (among nausea, photophobia, and phonophobia). Safety and tolerability were assessed.ResultsA total of 392 subjects was screened, 268 (68.4%) were randomized, and 234 (87.3% of those randomized) completed the double-blind treatment period. The proportion of subjects who were pain free at 2 h postdose was significantly greater in the DFN-11 group than in the placebo group (51.0% vs 30.8%, P  =  0.0023). Compared with placebo, significantly higher proportions of subjects treated with DFN-11 were also pain free at 30, 60, and 90 min postdose (P  ≤  0.0195). DFN-11 was significantly superior to placebo for pain relief at 60 min, 90 min, and 2 h postdose (P ≤ 0.0179). At 2 h postdose, DFN-11 was also significantly superior to placebo for freedom from photophobia (P  =  0.0056) and phonophobia (P  =  0.0167). Overall, 33.3% (37/111) who received DFN-11 and 13.4% (16/119) who received placebo experienced at least 1 treatment-emergent adverse event (TEAE), the most common of which were injection site swelling (7.2% vs 0.8%) and pain (7.2% vs 5.9%). Chest discomfort was about half as common in the DFN-11 treatment group as it was in the placebo group (0.9% vs 1.7%).ConclusionsThis study met its primary endpoint, pain freedom at 2 h postdose, with DFN-11 significantly better than placebo, and the incidence of TEAEs and triptan sensations with DFN-11 was low. The 3 mg dose of sumatriptan in DFN-11 appears to be an effective alternative to a 6 mg SC dose of sumatriptan, with good safety and tolerability. ( clinicaltrials.gov : NCT02569853; registered 07 October 2015)
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DFN-02, Sumatriptan 10Â mg Nasal Spray with Permeation Enhancer, for the Acute Treatment of Migraine: A Randomized, Double-Blind, Placebo-Controlled Study Assessing Functional Disability and Subject Satisfaction with Treatment.
BackgroundThe commercial formulation of sumatriptan nasal spray is an effective option for migraine patients requiring or preferring a non-oral route of drug administration, but its utility is limited by poor absorption and tolerability issues. DFN-02, a new formulation of sumatriptan 10 mg nasal spray, is co-formulated with a permeation enhancer that gives it pharmacokinetics comparable to subcutaneous sumatriptan. As reported previously, DFN-02 was significantly better than placebo on multiple efficacy endpoints at 2 h postdose, including pain freedom, absence of the most bothersome symptom, and pain relief, and its safety and tolerability profiles were excellent.ObjectiveThe objective of this study was to assess the efficacy of acute treatment of migraine with DFN-02, including its effect on migraine-related functional disability and patient satisfaction with treatment.MethodsThis was a multicenter, randomized, double-blind, placebo-controlled efficacy and safety study of DFN-02 in adults with episodic migraine. Functional disability and subject satisfaction with treatment were prespecified endpoints, assessed in real-time by subjects, using an electronic diary.ResultsIn total, 107 subjects were randomized. DFN-02 was significantly superior to placebo for the reduction in functional disability score from predose level at 2 h after treatment (- 1.2 vs. - 0.6, p < 0.001). Subjects treated with DFN-02 were also more likely to be satisfied or very satisfied than subjects treated with placebo at 2 h postdose (70.0% vs. 44.2%, p = 0.027). Using the Patient Perception of Migraine Questionnaire-Revised at 24 h postdose, DFN-02 mean scores were significantly superior to placebo for the subscales of efficacy (65.2 vs. 42.5, p = 0.016) and function (68.9 vs. 42.1, p = 0.001), and for total score (71.0 vs. 56.6, p = 0.016); global medication effectiveness (p = 0.027); and overall satisfaction (p = 0.019). Placebo was significantly better than DFN-02 on the tolerability subscale (94.8 vs. 88.5, p = 0.026). At 24 h postdose, subjects reported significantly higher satisfaction with DFN-02 compared with satisfaction reported pre-randomization regarding their usual migraine medication (p = 0.012).ConclusionDFN-02 was superior to placebo for the relief of migraine-related functional disability, and provided greater satisfaction than placebo or subjects' usual acute treatment.Trial registrationClinicalTrials.gov identifier: NCT02856802
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