970 resultados para malliavin calculus
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A multivariate curve resolution method, "GENERALIZED RANK ANNIHILATION METHOD (GRAM)", is discussed and tested with simulated and experimental data. The analysis of simulated data provides general guidelines concerning the condition for uniqueness of a solution for a given problem. The second-order emission-excitation spectra of human and animal dental calculus deposits were used as an experimental data to estimate the performance of the above method. Three porphyrinic spectral profiles, for both human and cat, were obtained by the use of GRAM.
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En esta investigación se ha estudiado la relación entre dos subsistemas de la memoria de trabajo (buclefonológico y agenda viso-espacial) y el rendimiento en cálculo con una muestra de 94 niños españolesde 7-8 años. Hemos administrado dos pruebas de cálculo diseñadas para este estudio y seis medidassimples de memoria de trabajo (de contenido verbal, numérico y espacial) de la «Batería de Testsde Memoria de Treball» de Pickering, Baqués y Gathercole (1999), y dos pruebas visuales complementarias.Los resultados muestran una correlación importante entre las medidas de contenido verbaly numérico y el rendimiento en cálculo. En cambio, no hemos encontrado ninguna relación con las medidasespaciales. Se concluye, por lo tanto, que en escolares españoles existe una relación importanteentre el bucle fonológico y el rendimiento en tareas de cálculo. En cambio, el rol de la agenda viso-espaciales nulo
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Desde que Hitch (1978) publicó el primer estudio sobre el rol de la memoria de trabajo en el cálculo han idoaumentando las investigaciones en este campo. Muchos trabajos han estudiado un único subsistema, pero nuestroobjetivo es identificar qué subsistema de la memoria de trabajo (bucle fonológico, agenda viso-espacial o ejecutivocentral) está más implicado en el cálculo mental. Para ello hemos realizado un estudio correlacional en el quehemos administrado dos pruebas aritméticas y nueve pruebas de la “Bateria de Test de Memòria de Treball” dePickering, Baqués y Gathercole (1999) a una muestra de 94 niños españoles de 7-8 años. Nuestros resultadosindican que el bucle fonológico y sobretodo el ejecutivo central inciden de forma estadísticamente significativa enel rendimiento aritmético
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Tutkimuksen tavoitteena oli kuvata hampaiden kiinnityskudossairauksien esiintyvyyttä ja suuhygieniatottumuksia Tansaniassa. Viiden eri tutkimuksen avulla kartoitettiin suuhygieniatottumuksia, kiinnityskudosten tilaa, kiinnityskudossairauksien riskitekijöitä ja hoidon tarvetta (CPITN) sekä ienvetäymiä. Tutkimukset toteutettiin eri paikkakunnilla vuosien 1987 ja 2003 välillä. Tutkittavat valittiin satunnaisesti tai harkitusti; tutkittavien määrä vaihteli 201:stä 1764:ään. Aineistot kerättiin kysymyslomakkeilla ja kliinisten tutkimusten avulla. Kliinisesti mitattiin plakin, hammaskiven ja ienten verenvuodon määrä, ientaskujen syvyys, ienvetäymien laajuus ja puuttuvien hampaiden lukumäärä. Tutkimusvälineinä käytettiin peiliä, Williamsin ja WHO:n ientaskumittareita. Muoviharjaksista hammasharjaa ilmoitti käyttävänsä 51,5-97,8% tutkituista. Ns. harjaustikun käyttö vaihteli paljon: 0,9-32,0 %. Plakkia löydettiin 65-100 %:lla tutkituista. Hammaskiveä oli suurimmalla osalla tutkituista. Myös ienverenvuotoa löytyi valtaosalta (79-100%). Ienverenvuotoa oli enemmän miehillä kuin naisilla sekä alhaisemman koulutustason omaavilla. Neljäkymmentä vuotta täyttäneiltä löydettiin 4–5 mm:n syvyisiä ientaskuja 82,1 %:lta ja ≥ 6 mm:n taskuja 43,8 %:lta. Suun terveystottumusten ohjaamiseen oli tarvetta yli 90 %:lla, hammaskiven poistoon ja juurten pinnan tasoitukseen yli 80%:lla. Yleisimmät riskitekijät kiinnityskudossairauksille olivat ikä (≥ 35 vuotta), miessukupuoli, alhainen koulutustaso, plakin, hammaskiven ja ientulehduksen määrä sekä asuminen maaseudulla. Ienvetäymiä (≥ 4 mm) löytyi noin 54%:lla tutkituista. Ienvetäymiä oli useammin miehillä kuin naisilla ja ne olivat yhteydessä ikään sekä hammaskiven ja ienverenvuodon esiintymiseen. Suuhygieniataso tutkituilla henkilöillä oli huono ja ienvetäymien esiintyvyys korkea. Syviä ientaskuja löytyi kuitenkin harvoilta tutkituilta. Riskitekijät kiinnityskudossairauksille olivat ikä, miessukupuoli, alhainen koulutustaso, plakin, hammaskiven ja ientulehduksen määrä sekä asuminen maaseudulla. Ienvetäymien riskit olivat ikä, miessukupuoli, hammaskivi ja ienverenvuoto
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Es presenten un seguit de coneixements i habilitats que haurien d’adquirir els alumnes de 6 a 12 anys dividits en cicle inicial, mitjà i superior, tot practicant jocs. Es presenten també 7 jocs amb instruccions per dur-los a terme
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The chemical amount values vary in a discrete or continuous form, depending on the approach used to describe the system. In classical sciences, the chemical amount is a property of the macroscopic system and, like any other property of the system, it varies continuously. This is neither inconsistent with the concept of indivisible particles forming the system, nor a mere approximation, but it is a sound concept which enables the use of differential calculus, for instance, in chemical thermodynamics. It is shown that the fundamental laws of chemistry are absolutely compatible to the continuous concept of the chemical amount.
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The electronic, structural properties and elastic constants of the wurtzite phase of zinc oxide, ZnO, was investigated using computer simulation at Density Functional Theory level, with B3LYP hybrid functional and Hartree-Fock methodology. The electronic properties as well the band energy was investigated through the analysis of the band structures and density of states (DOS), and the mechanical properties was studied through the calculus of the elastic constants C11, C33, C44, C12 e C13. The results are in good agreement with experimental data found in the literature and in accordance with results obtained by another theoretical methodology.
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The pollutant transference among reservoirs atmosphere-hydrosphere, relevant to the atmospheric chemistry, depends upon scavenging coefficient (Λ) calculus, which depends on the raindrop size distribution as well as on the rainfall systems, both different to each locality. In this work, the Λ calculus will be evaluated to gas SO2 and particulate matter fine and coarse among five sites in Germany and two in Brazil. The results show three possible classifications in function of Λ, comparable to literature, however with a greater range due to the differences of rainfall system sites. This preliminary study supports future researches
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This work describes the creation of an very simple calculation algorithm, based in basic chemical and mathematic principles, for the calculation of weak diprotic acid dissociation constants as, for example, amino acids, from potentiometric titrations. For an easier understanding of the algorithm the logical reasoning of this calculus is schematized in a diagram of blocks. In the second part of the work the algorithm is applied to an Excel calculation sheet to determine the dissociation constants of Nicotinic Acid and Glycine, from the respective potentiometric titration curves. The values obtained using this algorithm are compared with those estimated by Hyperquad2008 (program generally used for this type of calculus) and also with the values of a stability constants database.
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The importance of medicinal plants and their use in industrial applications is increasing worldwide, especially in Brazil. Phyllanthus species, popularly known as "quebra-pedras" in Brazil, are used in folk medicine for treating urinary infections and renal calculus. This paper reports an authenticity study, based on herbal drugs from Phyllanthus species, involving commercial and authentic samples using spectroscopic techniques: FT-IR, ¹H HR-MAS NMR and ¹H NMR in solution, combined with chemometric analysis. The spectroscopic techniques evaluated, coupled with chemometric methods, have great potential in the investigation of complex matrices. Furthermore, several metabolites were identified by the NMR techniques.
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ABSTRACT The aim of this paper is to discuss how Bruno Bauch deals with the problem of the coordination between empirical concepts and spatiotemporal objects. We shall argue that Bauch reformulates the Kantian distinction between concepts and intuitions by means of a philosophical consideration of differential calculus and that he thereby explains the possibility of such coordination, avoiding certain difficulties of the Kantian doctrine.
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Treatment, morbidity and mortality of patients with gallstone ileus depend on an accurate diagnosis made in time, and also on a more adequate therapeutic option.A detailed clinical evaluation is fundamental for such diagnosis. Complementary exams like a simple radiological study of the abdomen, high and low endoscopies, an ultrasonography, and a tomography can also be performed. The therapeutic options include the removal of the obstructive factor separately, the performance of a treatment in two separate stages, or the performance of a complete treatment (removal of the calculus, cholecystectomy, and the closing of the fistula).This study aims to present a case report of an elderly man of high surgical risk, presenting gallstone ileus. He was submitted to an isolated videoassisted enterolithotomy through a minilaparotomy. Taking into consideration the patients advanced age and the lack of evidence as to other biliary associated pathologies, the chosen treatment seemed to be a good alternative. The evolution was good, and after an 8 month follow-up the patient was found well and with no biliary symptoms whatsoever.
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Perforation of common bile duct (CBD) is usually associated with invasive procedures. Spontaneous perforation is rare, and more often described in neonates. We report a case of a spontaneous perforation of CBD in an adult with a family history of cholelithiasis, but with no calculus found during exploration of the biliary tree. The patient was successfully treated by cholecystectomy and T - tube drainage of the CBD.
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Formal methods provide a means of reasoning about computer programs in order to prove correctness criteria. One subtype of formal methods is based on the weakest precondition predicate transformer semantics and uses guarded commands as the basic modelling construct. Examples of such formalisms are Action Systems and Event-B. Guarded commands can intuitively be understood as actions that may be triggered when an associated guard condition holds. Guarded commands whose guards hold are nondeterministically chosen for execution, but no further control flow is present by default. Such a modelling approach is convenient for proving correctness, and the Refinement Calculus allows for a stepwise development method. It also has a parallel interpretation facilitating development of concurrent software, and it is suitable for describing event-driven scenarios. However, for many application areas, the execution paradigm traditionally used comprises more explicit control flow, which constitutes an obstacle for using the above mentioned formal methods. In this thesis, we study how guarded command based modelling approaches can be conveniently and efficiently scheduled in different scenarios. We first focus on the modelling of trust for transactions in a social networking setting. Due to the event-based nature of the scenario, the use of guarded commands turns out to be relatively straightforward. We continue by studying modelling of concurrent software, with particular focus on compute-intensive scenarios. We go from theoretical considerations to the feasibility of implementation by evaluating the performance and scalability of executing a case study model in parallel using automatic scheduling performed by a dedicated scheduler. Finally, we propose a more explicit and non-centralised approach in which the flow of each task is controlled by a schedule of its own. The schedules are expressed in a dedicated scheduling language, and patterns assist the developer in proving correctness of the scheduled model with respect to the original one.
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Olemassa olevat spektrieromittarit eivät vastaa riittävästi CIEDE2000-värieroa. Tämän työn tavoitteena oli toteuttaa menetelmä, joka laskee värispektrien eron siten, että tulos vastaa CIEDE2000-värieroa. Kehitystyön tuloksena syntyi menetelmä, joka perustuu ennalta laskettuihin eroihin tunnettujen spektrien välillä ja niiden perusteella johdettuihin laskentaparametreihin. menetelmällä pystyy laskemaan spektrieroja vain niiden spektrien välillä, jotka saadaan sekoittamalla tunnettuja spektrejä. Laskentaparametrien laskenta on työläs prosessi ja siksi menetelmään toteutettiin hajautus usealle tietokoneelle. Menetelmä saatiin vastaamaan hyvin CIEDE2000:ia suurimmalle osalle spektrejä harvoja poikkeuksia lukuunottamatta. Ongelmat johtuvat mallissa olevasta matemaattisesta ominaisuudesta. Spektrieromittari näyttää metameerisille spektreille nollasta poikkeavan arvon, vaikka CIEDE2000 näyttää nollaa. Tämä osoittaa spektrieromittarin oikeamman toiminnan CIEDE2000-värieroon verrattuna.