5,058 research outputs found

    The structures of fluorene– (H2O)1,2 determined by rotational coherence spectroscopy

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    Rotational coherence spectroscopy ~RCS!, via time-correlated single photon counting, and two-color resonant two-photon ionization ~R2PI! time-of-flight mass spectrometry, have been used to characterize fluorene–(water)1,2[FL– (H2O)1,2] van der Waals clusters generated in supersonic jets. Rotational coherence traces have been obtained at excitation energies corresponding to several resonant features in the S1\u3c-S0 R2PI spectra of FL– (H2O)1,2 . RCS simulations and diagonalization of the moment of inertia tensor have been used to obtain S1 excited state rotational constants and structures of FL– (H2O)1,2 that are consistent with the experimental rotational coherence traces. The RCS results indicate that: (i) the water molecule in FL–H2O resides above the central five member ring and interacts with both aromatic sites; (ii) the water molecules in FL– (H2O)2 form a water dimer that is most likely oriented along the long axis of fluorene and is hydrogen-bonded to both aromatic sites. The S1\u3c-S0 R2PI spectra of FL– (D2O)1,2 and FL–HDO have also been obtained. The 000 transition is a doublet in the R2PI spectra of FL–H2O, FL–D2O, and a singlet in the R2PI spectrum of FL–HDO. The presence of this doublet in the FL–H2O/D2O spectra, and the absence of such a splitting in the FL–HDO spectrum, is an indication of internal rotation of the water molecule on a potential energy surface that changes upon electronic excitation. Lastly, the use of RCS and time-resolved fluorescence as a tool for assigning features in R2PI spectra that are of ambiguous origin due to fragmentation of higher mass clusters into lower mass channels is demonstrated

    Clinical Outcomes After Four-Level Anterior Cervical Discectomy and Fusion.

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    Study Design: Retrospective cohort study. Objectives: Anterior cervical discectomy and fusion (ACDF) demonstrates reliable improvement in neurologic symptoms associated with anterior compression of the cervical spine. There is a paucity of data on outcomes following 4-level ACDFs. The purpose of this study was to evaluate clinical outcomes for patients undergoing 4-level ACDF. Methods: All 4-level ACDFs with at least 1-year clinical follow-up were identified. Clinical outcomes, including fusion rates, neurologic outcomes, and reoperation rates were determined. Results: Retrospective review of our institutional database revealed 25 patients who underwent 4-level ACDF with at least 1-year clinical follow-up. Average age was 57.5 years (range 38.2-75.0 years); 14 (56%) were male, and average body mass index was 30.2 kg/m Conclusions: Review of our institution\u27s experience demonstrated a low rate of revision cervical surgery for any reason of 8% at mean 19 months follow-up, and neurological examinations consistently improved, despite a high rate of radiographic nonunion (31%)

    Numerical Models of Binary Neutron Star System Mergers. I.: Numerical Methods and Equilibrium Data for Newtonian Models

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    The numerical modeling of binary neutron star mergers has become a subject of much interest in recent years. While a full and accurate model of this phenomenon would require the evolution of the equations of relativistic hydrodynamics along with the Einstein field equations, a qualitative study of the early stages on inspiral can be accomplished by either Newtonian or post-Newtonian models, which are more tractable. In this paper we offer a comparison of results from both rotating and non-rotating (inertial) frame Newtonian calculations. We find that the rotating frame calculations offer significantly improved accuracy as compared with the inertial frame models. Furthermore, we show that inertial frame models exhibit significant and erroneous angular momentum loss during the simulations that leads to an unphysical inspiral of the two neutron stars. We also examine the dependence of the models on initial conditions by considering initial configurations that consist of spherical neutron stars as well as stars that are in equilibrium and which are tidally distorted. We compare our models those of Rasio & Shapiro (1992,1994a) and New & Tohline (1997). Finally, we investigate the use of the isolated star approximation for the construction of initial data.Comment: 32 pages, 19 gif figures, manuscript with postscript figures available at http://www.astro.sunysb.edu/dswesty/docs/nspap1.p

    Benchmarking Treatment Response in Tourette’s Disorder: A Psychometric Evaluation and Signal Detection Analysis of the Parent Tic Questionnaire

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    This study assessed the psychometric properties of a parent-reported tic severity measure, the Parent Tic Questionnaire (PTQ), and used the scale to establish guidelines for delineating clinically significant tic treatment response. Participants were 126 children ages 9 to 17 who participated in a randomized controlled trial of Comprehensive Behavioral Intervention for Tics (CBIT). Tic severity was assessed using the Yale Global Tic Severity Scale (YGTSS), Hopkins Motor/Vocal Tic Scale (HMVTS) and PTQ; positive treatment response was defined by a score of 1 (very much improved) or 2 (much improved) on the Clinical Global Impressions – Improvement (CGI-I) scale. Cronbach’s alpha and intraclass correlations (ICC) assessed internal consistency and test-retest reliability, with correlations evaluating validity. Receiver- and Quality-Receiver Operating Characteristic analyses assessed the efficiency of percent and raw-reduction cutoffs associated with positive treatment response. The PTQ demonstrated good internal consistency (α = 0.80 to 0.86), excellent test-retest reliability (ICC = .84 to .89), good convergent validity with the YGTSS and HM/VTS, and good discriminant validity from hyperactive, obsessive-compulsive, and externalizing (i.e., aggression and rule-breaking) symptoms. A 55% reduction and 10-point decrease in PTQ Total score were optimal for defining positive treatment response. Findings help standardize tic assessment and provide clinicians with greater clarity in determining clinically meaningful tic symptom change during treatment

    Robótica para a Inclusão Social (RISO): promovendo a robótica na comunidade e inserindo discentes no contexto social

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    Anais do 35º Seminário de Extensão Universitária da Região Sul - Área temática: EducaçãoO Grupo Estudantil de Robótica Móvel (GERM) promove iniciativas de ensino, pesquisa e extensão no âmbito da disseminação da robótica. Dentre as iniciativas centradas na extensão encontra-se o programa de extensão Robótica para a Inclusão Social (RISO), que tem por objetivo a aproximação da sociedade com a área da robótica, incentivando crianças e adolescentes do município de Joinville/SC a ingressarem no ensino superior. O programa é composto por três ações, que difundem a robótica na sociedade através de aulas ministradas com kits de robôs LEGO MINDSTORMS® em escolas da rede pública e instituições carentes, campeonatos e outros eventos relacionados a área. O RISO já alcançou uma quantidade expressiva de pessoas na comunidade interna e externa, tornando-se uma ação extensionista de referência na regiã

    Definition of Nonresponse to Analgesic Treatment of Arthritic Pain: An Analytical Literature Review of the Smallest Detectable Difference, the Minimal Detectable Change, and the Minimal Clinically Important Difference on the Pain Visual Analog Scale

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    Our objective was to develop a working definition of nonresponse to analgesic treatment of arthritis, focusing on the measurement of pain on the 0–100 mm pain visual analog scale (VAS). We reviewed the literature to assess the smallest detectable difference (SDD), the minimal detectable change (MDC), and the minimal clinically important difference (MCID). The SDD for improvement reported in three studies of rheumatoid arthritis was 18.6, 19.0, and 20.0. The median MDC was 25.4 for 7 studies of osteoarthritis and 5 studies of rheumatoid arthritis (calculated for a reliability coefficient of 0.85). The MCID increased with increasing baseline pain score. For baseline VAS tertiles defined by scores of 30–49, 50–65, and >65, the MCID for improvement was, respectively, 7–11 units, 19–27 units, and 29–37 units. Nonresponse can thus be defined in terms of the MDC for low baseline pain scores and in terms of the MCID for high baseline scores
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