72 research outputs found

    High sensitivity phonon spectroscopy of Bose-Einstein condensates using matter-wave interference

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    We study low momentum excitations of a Bose-Einstein condensate using a novel matter-wave interference technique. In time-of-flight expansion images we observe strong matter-wave fringe patterns. The fringe contrast is a sensitive spectroscopic probe of in-trap phonons and is explained by use of a Bogoliubov excitation projection method applied to the rescaled order parameter of the expanding condensate. Gross-Pitaevskii simulations agree with the experimental data and confirm the validity of the theoretical interpretation. We show that the high sensitivity of this detection scheme gives access to the quantized quasiparticle regime.Comment: 5 pages, 5 figures, author list update

    Influence of the number of trials and the exercise to rest ratio in repeated sprint ability, with changes of direction and orientation

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    The purpose of this investigation was to determine if there were different trends in physical fatigue observed in 3 different sets, of 7 trials each, in repeated sprint training, performed in 3 different modes: straight sprinting over 30 m, shuttle sprinting over 15 + 15 m, and sprinting over 30 m with changes of direction. Recovery time among trials in the sets was administered according to the 1:5 exercise to rest ratio. The sets were performed on 3 different days, with at least 48 hours between each set. The study involved 17 trained male soccer players (height, 177.33 +/- 6.21 cm; body mass, 71.63 +/- 9.58 kg; body mass index, 23 +/- 2.39 kg<bold>m(</bold>-2); age, 21.94 +/- 3.58 years). To compare the different values of the time recorded, an index of fatigue was used. Significant differences among trials within each set (repeated measures analysis of variance; p < 0.05) and between the sets (factorial analysis of variance; p < 0.001) were found. Significant correlations between each test and countermovement jump and stiffness values recorded pre exercise were found (p < 0.05). Significant differences between countermovement jump and stiffness values recorded pre and post exercise were also found (p < 0.05). This study suggests that training sessions aimed at increasing the capacity of repeated sprint ability in nonlinear and multidirectional sprints (shuttle and change of direction), which might imply a different number of trials within the set or different exercise to rest ratios from the ones usually adopted for straight sprinting, to induce similar trends of fatigue. As practical applications, the estimated numbers of necessary trials in the different sets and the possible exercise to rest ratios, resulting from mathematical modeling, are provided for each investigated sprinting mode

    Precise reply and clarifications on behalf of Sicilian Public Health Authorities to the case report published by La Rosa and collegues

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    As a results of the case report “Post-rotavirus vaccine intussusception in identical twins: a case report” recently published on Human Vaccines & Immunotherapy by La Rosa et al., the principal Sicilian Public Health Authorities decided to specify several points and underline some important details omitted by the authors. In particular, aims to underline the remarkable benefit for Sicilian Regional Health service after the introduction of the rotavirus vaccination. Universal mass vaccination against rotavirus is properly managed by the Regional Health Authorities and is contributing to a consistent increase of public health in the Sicilian pediatric population; any modification of such a program should be based on robust scientific evidences. Finally, a single case report should not be considered as a basis to recommend a change in the clinical practice but instead a possible point of start for discussion and research

    Bragg spectroscopy of a strongly interacting Bose-Einstein condensate

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    We study Bragg spectroscopy of a strongly interacting Bose-Einstein condensate using time-dependent Hartree-Fock-Bogoliubov theory. We include approximatively the effect of the momentum dependent scattering amplitude which is shown to be the dominant factor in determining the spectrum for large momentum Bragg scattering. The condensation of the Bragg scattered atoms is shown to significantly alter the observed excitation spectrum by creating a novel pairing channel of mobile pairs.Comment: 11 pages, 4 figure

    Bogoliubov spectrum and Bragg spectroscopy of elongated Bose-Einstein condensates

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    The behavior of the momentum transferred to a trapped Bose-Einstein condensate by a two-photon Bragg pulse reflects the structure of the underlying Bogoliubov spectrum. In elongated condensates, axial phonons with different number of radial nodes give rise to a multibranch spectrum which can be resolved in Bragg spectroscopy, as shown by Steinhauer {\it et al.} [Phys. Rev. Lett. {\bf 90}, 060404 (2003)]. Here we present a detailed theoretical analysis of this process. We calculate the momentum transferred by numerically solving the time dependent Gross-Pitaevskii equation. In the case of a cylindrical condensate, we compare the results with those obtained by linearizing the Gross-Pitaevskii equation and using a quasiparticle projection method. This analysis shows how the axial-phonon branches affect the momentum transfer, in agreement with our previous interpretation of the observed data. We also discuss the applicability of this type of spectroscopy to typical available condensates, as well as the role of nonlinear effects.Comment: 8 pages, 7 figures, minor changes, typos correcte

    Early Immunotherapy and Longer Corticosteroid Treatment Are Associated With Lower Risk of Relapsing Disease Course in Pediatric MOGAD

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    Background and Objectives We sought to identify early factors associated with relapse and outcome in paediatric-onset myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD). Methods In a multicenter retrospective cohort of pediatric MOGAD (≀18 years), onset features and treatment were compared in patients with monophasic vs relapsing disease (including cases with follow-up ≄12 months after onset or relapse at any time) and in patients with final Expanded Disability Status Scale (EDSS) 0 vs ≄1 at last follow-up (including cases with followup >3 months after last event or EDSS0 at any time). Multivariable logistic regression models were used to evaluate factors associated with relapsing disease course and EDSS ≄ 1 at final follow-up. Results Seventy-five children were included (median onset age 7 years; median 30 months of follow-up). Presentation with acute disseminated encephalomyelitis was more frequent in children aged 8 years or younger (66.7%, 28/42) than in older patients (30.3%, 10/33) (p = 0.002), whereas presentation with optic neuritis was more common in children older than 8 years (57.6%, 19/33) than in younger patients (21.4%, 9/42) (p = 0.001). 40.0% (26/65) of patients relapsed. Time to first relapse was longer in children aged 8 years or younger than in older patients (median 18 vs 4 months) (p = 0.013). Factors at first event independently associated with lower risk of relapsing disease course were immunotherapy <7 days from onset (6.7-fold reduced odds of relapsing course, OR 0.15, 95% CI 0.03–0.61, p = 0.009), corticosteroid treatment for ≄5 weeks (6.7-fold reduced odds of relapse, OR 0.15, 95% CI 0.03–0.80, p = 0.026), and abnormal optic nerves on onset MRI (12.5-fold reduced odds of relapse, OR 0.08, 95% CI 0.01–0.50, p = 0.007). 21.1% (15/71) had EDSS ≄ 1 at final follow-up. Patients with a relapsing course had a higher proportion of final EDSS ≄ 1 (37.5%, 9/24) than children with monophasic disease (12.8%, 5/39) (p = 0.022, univariate analysis). Each 1-point increment in worst EDSS at onset was independently associated with 6.7-fold increased odds of final EDSS ≄ 1 (OR 6.65, 95% CI 1.33–33.26, p = 0.021). Discussion At first attack of pediatric MOGAD, early immunotherapy, longer duration of corticosteroid treatment, and abnormal optic nerves on MRI seem associated with lower risk of relapse, whereas higher disease severity is associated with greater risk of final disability (EDSS ≄ 1)

    Data monitoring roadmap. The experience of the Italian Multiple Sclerosis and Related Disorders Register

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    Introduction Over the years, disease registers have been increasingly considered a source of reliable and valuable population studies. However, the validity and reliability of data from registers may be limited by missing data, selection bias or data quality not adequately evaluated or checked.This study reports the analysis of the consistency and completeness of the data in the Italian Multiple Sclerosis and Related Disorders Register.MethodsThe Register collects, through a standardized Web-based Application, unique patients.Data are exported bimonthly and evaluated to assess the updating and completeness, and to check the quality and consistency. Eight clinical indicators are evaluated.ResultsThe Register counts 77,628 patients registered by 126 centres. The number of centres has increased over time, as their capacity to collect patients.The percentages of updated patients (with at least one visit in the last 24 months) have increased from 33% (enrolment period 2000-2015) to 60% (enrolment period 2016-2022). In the cohort of patients registered after 2016, there were &gt;= 75% updated patients in 30% of the small centres (33), in 9% of the medium centres (11), and in all the large centres (2).Clinical indicators show significant improvement for the active patients, expanded disability status scale every 6 months or once every 12 months, visits every 6 months, first visit within 1 year and MRI every 12 months.ConclusionsData from disease registers provide guidance for evidence-based health policies and research, so methods and strategies ensuring their quality and reliability are crucial and have several potential applications

    What happens to the BRONJ patients when re-classified according to the novel SICMFSIPMO recommendations? Our experience

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    Background. Since 2009, according to the American Association of Oral and Maxillofacial Surgeons staging system (AAOMS-SS), Bisphosphonate Related Osteonecrosis of the Jaw (BRONJ) has been defined by the presence of bone exposition; in absence of this condition, patients presenting other unspecific clinical and/or radiological signs of disease were classified into the \u201cstage 0\u201d. In 2012, the Italian Society of Maxillo-Facial Surgery (SICMF) and the Italian Society of Oral Pathology and Medicine (SIPMO) redefined BRONJ, as an adverse drug event, with several clinical forms (exposed and not-exposed), and updated the staging system, abolishing the stage 0. Aim of this study was to re-classify BRONJ cases in order to define the most adequate managements accordingly. Method. A retrospective database analysis of BRONJ cases observed at the Sector of Oral Medicine-University of Palermo from 2005 to 2012 was performed. A total of 93 patients (M: 27; F: 66; mean age \ub1 SD 69 \ub17yy), previously classified according 2009 AAOMS-SS (stages 0, 1, 2 and 3), were reclassified according 2012 SICMF-SIPMO staging system (SS-SS) [stage 1 (focal); 2 (diffuse) and 3 complicated)]. Results. In our sample, BRONJ AAOMS staging was the following: \u201cstage 0\u201d 16/93 (17.2%); \u201cstage 1\u201d 16/93 (17.2%); \u201cstage 2\u201d 48/93 (51.6%) and \u201cstage 3\u201d 13/93 (14%). On the basis of the novel SS-SS, distribution of cases were: \u201cstage 1\u201d 33/93 (35.5%); \u201cstage 2\u201d 41/93 (44.1%) and \u201cstage 3\u201d 19/93 (20.4%). Of the 16 cases \u201cstage 0\u201d, 6/16 (37.5%) has become \u201cstage 1\u201d; 6/16 (37.5%) \u201cstage 2\u201d and 4/16 (25%) \u201cstage 3\u201d, respectively. Conclusion. After the re-classification, a large quote of BRONJ cases, previously underestimated as stage 0, were properly diagnosed as diffuse-complicated cases. According to our experience, the updated staging system provide important clinical benefits, such as anticipating BRONJ diagnosis, performing therapies earlier and adequate to the correct staging, in order to increase treatment effectiveness
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