968 resultados para Chebyshev polynomials of the first kind
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Falls are common in the elderly, and potentially result in injury and disability. Thus, preventing falls as soon as possible in older adults is a public health priority, yet there is no specific marker that is predictive of the first fall onset. We hypothesized that gait features should be the most relevant variables for predicting the first fall. Clinical baseline characteristics (e.g., gender, cognitive function) were assessed in 259 home-dwelling people aged 66 to 75 that had never fallen. Likewise, global kinetic behavior of gait was recorded from 22 variables in 1036 walking tests with an accelerometric gait analysis system. Afterward, monthly telephone monitoring reported the date of the first fall over 24 months. A principal components analysis was used to assess the relationship between gait variables and fall status in four groups: non-fallers, fallers from 0 to 6 months, fallers from 6 to 12 months and fallers from 12 to 24 months. The association of significant principal components (PC) with an increased risk of first fall was then evaluated using the area under the Receiver Operator Characteristic Curve (ROC). No effect of clinical confounding variables was shown as a function of groups. An eigenvalue decomposition of the correlation matrix identified a large statistical PC1 (termed "Global kinetics of gait pattern"), which accounted for 36.7% of total variance. Principal component loadings also revealed a PC2 (12.6% of total variance), related to the "Global gait regularity." Subsequent ANOVAs showed that only PC1 discriminated the fall status during the first 6 months, while PC2 discriminated the first fall onset between 6 and 12 months. After one year, any PC was associated with falls. These results were bolstered by the ROC analyses, showing good predictive models of the first fall during the first six months or from 6 to 12 months. Overall, these findings suggest that the performance of a standardized walking test at least once a year is essential for fall prevention.
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BACKGROUND: Deep brain stimulation (DBS) is recognized as an effective treatment for movement disorders. We recently changed our technique, limiting the number of brain penetrations to three per side. OBJECTIVES: The first aim was to evaluate the electrode precision on both sides of surgery since we implemented this surgical technique. The second aim was to analyse whether or not the electrode placement was improved with microrecording and macrostimulation. METHODS: We retrospectively reviewed operation protocols and MRIs of 30 patients who underwent bilateral DBS. For microrecording and macrostimulation, we used three parallel channels of the 'Ben Gun' centred on the MRI-planned target. Pre- and post-operative MRIs were merged. The distance between the planned target and the centre of the implanted electrode artefact was measured. RESULTS: There was no significant difference in targeting precision on both sides of surgery. There was more intra-operative adjustment of the second electrode positioning based on microrecording and macrostimulation, which allowed to significantly approach the MRI-planned target on the medial-lateral axis. CONCLUSION: There was more electrode adjustment needed on the second side, possibly in relation with brain shift. We thus suggest performing a single central track with electrophysiological and clinical assessment, with multidirectional exploration on demand for suboptimal clinical responses.
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Introduction La stimulation cérébrale profonde est reconnue comme étant un traitement efficace des pathologies du mouvement. Nous avons récemment modifié notre technique chirurgicale, en limitant le nombre de pénétrations intracérébrales à trois par hémisphère. Objectif Le premier objectif de cette étude est d'évaluer la précision de l'électrode implantée des deux côtés de la chirurgie, depuis l'implémentation de cette technique chirurgicale. Le deuxième objectif est d'étudier si l'emplacement de l'électrode implantée était amélioré grâce à l'électrophysiologie. Matériel et méthode Il s'agit d'une étude rétrospective reprenant les protocoles opératoires et imageries à résonnance magnétique (IRM) cérébrales de 30 patients ayant subi une stimulation cérébrale profonde bilatérale. Pour l'électrophysiologie, nous avons utilisé trois canules parallèles du « Ben Gun », centrées sur la cible planifiée grâce à l'IRM. Les IRM pré- et post-opératoires ont été fusionnées. La distance entre la cible planifiée et le centre de l'artéfact de l'électrode implantée a été mesurée. Résultats Il n'y a pas eu de différence significative concernant la précision du ciblage des deux côtés (hémisphères) de la chirurgie. Il y a eu plus d'ajustements peropératoires du deuxième côté de la chirurgie, basé sur l'électrophysiologie, ce qui a permis d'approcher de manière significative la cible planifiée grâce à l'IRM, sur l'axe médio- latéral. Conclusion Il y a plus d'ajustements nécessaires de la position de la deuxième électrode, possiblement en lien avec le « brain shift ». Nous suggérons de ce fait d'utiliser une trajectoire d'électrode centrale accompagnée par de l'électrophysiologie, associé à une évaluation clinique. En cas de résultat clinique sub-optimal, nous proposons d'effectuer une exploration multidirectionnelle.
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Abstract Objective: To assess the prevalence of isolated findings of abnormalities leading to entrapment of the lateral plantar nerve and respective branches in patients complaining of chronic heel pain, whose magnetic resonance imaging exams have showed complete selective fatty atrophy of the abductor digiti quinti muscle. Materials and Methods: Retrospective, analytical, and cross-sectional study. The authors selected magnetic resonance imaging of hindfoot of 90 patients with grade IV abductor digiti quinti muscle atrophy according to Goutallier and Bernageau classification. Patients presenting with minor degrees of fatty muscle degeneration (below grade IV) and those who had been operated on for nerve decompression were excluded. Results: A female prevalence (78.8%) was observed, and a strong correlation was found between fatty muscle atrophy and plantar fasciitis in 21.2%, and ankle varices, in 16.8% of the patients. Conclusion: Fatty atrophy of the abductor digiti quinti muscle is strongly associated with neuropathic alterations of the first branch of the lateral plantar nerve. The present study showed a significant association between plantar fasciitis and ankle varices with grade IV atrophy of the abductor digiti quinti muscle.
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A very little known aspect of the scientific career of Regnault is his contribution to the emerging organic chemistry in the first half of the nineteenth century. The purpose of this article is not only to describe two of his most important researches in this field, as were the discovery of two series of halogenated derivates of certain organic compounds and the precise identification of some of the then recently discovered alkaloids, but also the main features that identified his research method. With the involvement in these subjects, Regnault unintentionally positioned himself in the midst of some of the polemics about the classification of organic compounds that characterized this age of science.
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This work presents the use of potentiometric measurements for kinetic studies of biosorption of Cd2+ ions from aqueous solutions on Eichhornia crassipes roots. The open circuit potential of the Cd/Cd2+ electrode of the first kind was measured during the bioadsorption process. The amount of Cd2+ ions accumulated was determined in real time. The data were fit to different models, with the pseudo-second-order model proving to be the best in describing the data. The advantages and limitations of the methodology proposed relative to the traditional method are discussed.
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Tutkimukseni käsittelee ensimmäisen ristiretken (1095–1101) varhaista latinankielistä historiankirjoitusta. Tarkastelun keskiössä ovat kolmen benediktiinimunkin historiateokset, jotka perustuvat anonyymin kirjoittajan silminnäkijäkertomukseen nimeltä Gesta Francorum et aliorum Hierosolymitanorum. Benediktiinit ilmoittivat pyrkineensä ennen kaikkea korjaamaan kyseisen teoksen tyyliä. Samalla he kuitenkin tulivat tuottaneeksi varsin erilaista kuvaa ristiretkestä ja ristiritarista. Tutkimuksessani tarkastelen yksityiskohtaisesti ja eri versioita vertaillen sitä, miten ristiretken historiaa kirjoitettiin ja uudelleenkirjoitettiin. Mitä kohtia munkit pyrkivät muuttamaan, miten he sen tekivät ja miksi? Kiinnitän huomioni teoksissa käytettyyn retoriikkaan sekä siihen mitä jätettiin kertomatta. Oletetun lukijan käsitettä hyödyntäen pohdin myös teosten mahdollista ja todennäköistä kohdeyleisöä – siis sitä, kenelle historiaa ensimmäisestä ristiretkestä kirjoitettiin. Ensimmäistä ristiretkeä koskevat käsityksemme perustuvat suuressa määrin tarkastelemiini kertomuksiin ja niiden toisintoihin. Ilman lähteiden retorista analyysiä ja kontekstualisointia monet faktoina pitämämme tulkinnat uhkaavat kuitenkin osoittautua hiekkarakennelmiksi. Tutkimuksessani korostan toisaalta silminnäkijäkertomusten ja uudelleenkirjoitusten välisiä eroja, toisaalta sitä, että myös uudelleentulkintojen välillä oli huomattavia eroavuuksia. Tästä syystä on tärkeää, että ristiretkeä koskevat ajatukset ankkuroidaan lähteisiinsä, eikä yleistyksiä viedä liian pitkälle. Yhteistä näille kertomuksille on se, että ne kuvasivat menneisyyttä omasta ajastaan käsin ilman pyrkimystä menneisyyden tavoittamiseksi ”niin kuin se oikeasti oli”. Tutkimukseni osoittaa, että ensimmäisen ristiretken aikalaiskertomukset ovat tiettyjen tarkoitusperien vuoksi tuotettuja retorisia tekstejä, joita ei tulisi arvioida faktuaalisen totuuskäsityksen kautta. Ne kertovat meille vain vähän siitä, mitä oikeasti tapahtui, mutta varsin paljon siitä, miten tapahtunut ymmärrettiin ja miten se haluttiin esittää.
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In this study, we report the characterization of a strain of Enterococcus faecium vanA, which grows only in the presence of vancomycin (VDEfm-UEL). The bacterium was isolated from the feces of a female patient who had undergone surgical treatment of Reinke’s edema and was receiving intravenous vancomycin therapy for infection with methicillin/oxacillin-resistant Staphylococcus aureus, a postoperative complication. Antimicrobial dependence was further confirmed by the vancomycin E-test. VDEfm-UEL was also shown to be resistant to ampicillin, ciprofloxacin, chloramphenicol, erythromycin, levofloxacin, penicillin, rifampicin, and teicoplanin. The putative virulence genes efaA, gelE and esp were detected by PCR. The ddl gene from VDEfm-UEL was cloned and sequenced. Vancomycin dependence seems to be associated with the insertion of a nucleotide in that sequence, which results in a frame-shift mutation, introducing a premature stop codon. This is the first report of vancomycin-dependent E. faecium isolation in a university hospital in Brazil.
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"February 7, 1817, ordered to be printed for the use of the Senate." Message addressed to the Senate and dated February 7th, 1817. Consists of the covering letter from the President and a report from the Secretary of State, dated Department of State, February 5th, 1817; which itself consists largely of diplomatic correspondence between the United States and Great Britain Relates to the restitution of captured slaves by the British during the War of 1812-1814.
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UANL
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Affiliation: H. Philippe: Département de Biochimie, Université de Montréal
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UANL
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A los comienzos de la historia del ser humano se le denomina 'prehistoria' pues el hombre no habia desarrollado aún la forma de escribir y, por tanto, solamente existen hallazgos arqueológicos como testimonio para conocer su más remoto pasado. Durante este largo período de tiempo, que abarca las Edades de Piedra, Bronce y Hierro, las primeras comunidades humanas vivian protegidas en cuevas, se alimentaban de los animales que cazaban y la piel de éstos servia para vestirse, sus herramientas eran de madera y piedra y no existian las ciudades ni grandes construcciones.
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Dividido en tres partes, se repasan en ellas las características de las cinco grandes potencias europeas del momento: los imperios británico, alemán, ruso, austro-húngaro y la república de Francia, así como las figuras de sus gobernantes; en segundo lugar, trata de la expansión por el continente de un frágil sistema de alianzas, y por último, del polvorín político de los Balcanes. Incluye fragmentos de fuentes históricas originales, así como material de aprendizaje activo: ejercicios, preguntas y pruebas.
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En 1918 finalizó la Primera Guerra Mundial y a partir de este momento, se inician las negociaciones para elaborar unos tratados de paz, que preparen la reorganización de Europa. El autor muestra cómo los años 1919-1925 son de una frágil paz e invita a los lectores a un juego de simulación en el que, representando a los estadistas de la época establezcan sus propios acuerdos de paz. Incluye fragmentos de fuentes históricas originales, así como, material de aprendizaje activo: ejercicios, preguntas, y pruebas.