389 research outputs found

    Moments of Autocorrelation Demerit Factors of Binary Sequences

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    Sequences with low aperiodic autocorrelation are used in communications and remote sensing for synchronization and ranging. The autocorrelation demerit factor of a sequence is the sum of the squared magnitudes of its autocorrelation values at every nonzero shift when we normalize the sequence to have unit Euclidean length. The merit factor, introduced by Golay, is the reciprocal of the demerit factor. We consider the uniform probability measure on the 2ℓ2^\ell binary sequences of length ℓ\ell and investigate the distribution of the demerit factors of these sequences. Previous researchers have calculated the mean and variance of this distribution. We develop new combinatorial techniques to calculate the ppth central moment of the demerit factor for binary sequences of length ℓ\ell. These techniques prove that for p≄2p\geq 2 and ℓ≄4\ell \geq 4, all the central moments are strictly positive. For any given pp, one may use the technique to obtain an exact formula for the ppth central moment of the demerit factor as a function of the length ℓ\ell. The previously obtained formula for variance is confirmed by our technique with a short calculation, and we demonstrate that our techniques go beyond this by also deriving an exact formula for the skewness.Comment: 40 page

    Halliwick-Based Aquatic Assessments : Reliability and Validity

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    Purpose: To investigate the reliability and validity of 2 aquatic functional assessment tests (Water Orientation Test of Alyn 1 and 2: WOTA1, WOTA2) for evaluating adjustment and functional ability in the aquatic environment based on the Halliwick concept. Methods: Thirty-two children with disabilities participated in the reliability study. Thirty-three other children participated in the validity study, which tested the correlations between the WOTA total score and motor performance on land. Results: Test-retest reliability for total score was found to be excellent for both WOTA1 (ICC = .97) and WOTA2 (ICC = 0.93, 0.97). The reliability for most of the individual item scores was fair to good (kappa \u3e 0.4). A positive moderately significant association was found between the WOTA total score and motor performance on land. Conclusion: Both assessments appear to be reliable and valid instruments for assessing mental adjustment and aquatic function in children with disabilities

    Lack of Association between Anti-Phospholipid Antibodies (APLA) and Attention Deficit/Hyperactivity Disorder (ADHD) in Children

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    Numerous studies have shown the pathological influence anti-phospholipid antibodies (APLA) have on the physiology of the single neuron as well as the function of the entire human nervous system. The influence is well demonstrated in the antiphospholipid syndrome (APS). This syndrome is characterized by a triad of arterial or venous thrombotic events, recurrent fetal loss and thrombocytopenic purpura. The syndrome exhibits different neurological pathologies such as: chorea, seizures, transverse myelopathy, migraine, cerebral ataxia, hemiballismus and transient global amnesia, which are not fully explained by the procoagulopathic trait of APLA. A study on mice induced with APS demonstrated hyperactive behavior when compared to the control group. The information gathered from these different studies raised the question whether APLA has any part in the etiology of Attention Deficit/Hyperactive Disorder (ADHD) in children

    Palliative care and Parkinson's disease : meeting summary and recommendations for clinical research

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    Introduction: Palliative care is an approach to caring for patients and families affected by serious illnesses that focuses on the relief of suffering through the management of medical symptoms, psychosocial issues, advance care planning and spiritual wellbeing. Over the past decade there has been an emerging clinical and research interest in the application of palliative care approaches to Parkinson’s disease (PD) and outpatient palliative care services are now offered by several movement disorders centers. Methods: An International Working Group Meeting on PD and Palliative Care supported by the Parkinson’s Disease Foundation was held in October 2015 to review the current state of the evidence and to make recommendations for clinical research and practice. Results: Topics included: 1) Defining palliative care for PD; 2) Lessons from palliative care for heart failure and other chronic illnesses; 3) Patient and caregiver Needs; 4) Needs assessment tools; 5) Intervention strategies; 6) Predicting prognosis and hospice referrals; 7) Choice of appropriate outcome measures; 8) Implementation, dissemination and education research; and 9) Need for research collaborations. We provide an overview of these discussions, summarize current evidence and practices, highlight gaps in our knowledge and make recommendations for future research. Conclusions: Palliative Care for PD is a rapidly growing area which holds great promise for improving outcomes for PD patients and their caregivers. While clinical research in this area can build from lessons learned in other diseases, there is a need for observational, methodological and interventional research to address the unique needs of PD patients and caregivers

    The Norian "chaotic carbon interval": New clues from the ÎŽ13Corg record of the Lagonegro Basin (southern Italy)

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    A global carbon-isotope curve for the Late Triassic has the potential for global correlations and new insights on the complex and extreme environmental changes that took place in this time interval. We reconstruct the global Ύ 13 C org profile for the late Norian, improving on sparse published data from North American successions that depict a "chaotic carbon-isotope interval" with rapid oscillations. In this context, we studied three sections outcropping in the Lagonegro Basin (southern Italy), originally located in the western Tethys. The carbon-isotope profiles show four negative excursions correlatable within the Lagonegro Basin. In particular, a negative shift close to the Norian/Rhaetian boundary (NRB) appears to correlate with that observed in the North American Ύ 13 C org record, documenting the widespread occurrence of this carbon cycle perturbation. The 87 Sr/ 86 Sr and 187 Os/ 188 Os profiles suggest that this negative shift was possibly caused by emplacement of a large igneous province (LIP). The release of greenhouse gases (CO 2 ) to the atmosphere-ocean system is supported by the 12 C enrichment observed, as well as by the increase of atmospheric p CO 2 inferred by different models for the Norian/Rhaetian interval. The trigger of this strongly perturbed interval could thus be enhanced magmatic activity that could be ascribed to the Angayucham province (Alaska, North America), a large oceanic plateau active ca. 214 ± 7 Ma, which has an estimated volume comparable to the Wrangellia and the Central Atlantic Magmatic Province (CAMP) LIPs. In fact, these three Late Triassic igneous provinces may have caused extreme environmental and climate changes during the Late Triassic

    Anpassung an regionale Klimafolgen kommunizieren : Konzepte, Herausforderungen und Perspektiven

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    Der Klimawandel ist nicht nur ein globales Problem, sondern wird auch konkrete Folgen fĂŒr die Menschen in Deutschland haben. Nur wenn es gelingt, die zukĂŒnftigen KlimaverĂ€nderungen und ihre voraussichtlichen Folgen zu kommunizieren, ist eine rechtzeitige Anpassung möglich. Nur dann können Gefahren minimiert und Chancen genutzt werden. Wie aber kann vermittelt werden, dass die Anpassung an Klimafolgen notwendig ist - obwohl unbekannt ist, welches Ausmaß die KlimaverĂ€nderungen und die Folgen in der Region haben werden? Bei wem fĂŒhren eher moralische und bei wem eher nutzenorientierte Argumente zu erhöhter Handlungsbereitschaft? Welche Kommunikationsmethoden eignen sich fĂŒr welche Zielgruppen? Wie können Jugendliche fĂŒr das Zusammenspiel von Klimaschutz und Anpassung sensibilisiert werden? Fundierte TheorieansĂ€tze und zahlreiche Praxisberichte erschließen den vergleichsweise neuen Aufgabenbereich "Klimaanpassungskommunikation". Eine steckbriefhafte Zusammenstellung von erprobten Instrumenten und Formaten illustriert, welche Maßnahmen Erfolg versprechen

    Trendy e-cigarettes enter Europe: chemical characterization of JUUL pods and its aerosols

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    The popularity and the high nicotine content of the American pod e-cigarette JUUL have raised many concerns. To comply with European law, the nicotine concentration in the liquids of the European version, which has been recently released on the market, is limited to below 20 mg/mL. This limit can possibly be circumvented by technological adjustments that increase vaporization and consequently, elevate nicotine delivery. In this study, we compare vapor generation and nicotine delivery of the initial European version, a modified European version, and the original American high-nicotine variant using a machine vaping set-up. Additionally, benzoic acid and carbonyl compounds are quantified in the aerosol. Further, concentrations of nicotine, benzoic acid, propylene glycol, and glycerol, along with the density and pH value of JUUL e-liquids have been assessed. Whereas the initial European version did not compensate for the low nicotine content in the liquid, we provide evidence for an increased vaporization by the modified European version. As a consequence, nicotine delivery per puff approximates the American original. Notably, this is not associated with an increased generation of carbonyl compounds. Our data suggest a similar addictiveness of the enhanced European version and the original American product
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