857 resultados para Nodal solution
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Schizophrenia is postulated to be the prototypical dysconnection disorder, in which hallucinations are the core symptom. Due to high heterogeneity in methodology across studies and the clinical phenotype, it remains unclear whether the structural brain dysconnection is global or focal and if clinical symptoms result from this dysconnection. In the present work, we attempt to clarify this issue by studying a population considered as a homogeneous genetic sub-type of schizophrenia, namely the 22q11.2 deletion syndrome (22q11.2DS). Cerebral MRIs were acquired for 46 patients and 48 age and gender matched controls (aged 6-26, respectively mean age = 15.20 ± 4.53 and 15.28 ± 4.35 years old). Using the Connectome mapper pipeline (connectomics.org) that combines structural and diffusion MRI, we created a whole brain network for each individual. Graph theory was used to quantify the global and local properties of the brain network organization for each participant. A global degree loss of 6% was found in patients' networks along with an increased Characteristic Path Length. After identifying and comparing hubs, a significant loss of degree in patients' hubs was found in 58% of the hubs. Based on Allen's brain network model for hallucinations, we explored the association between local efficiency and symptom severity. Negative correlations were found in the Broca's area (p < 0.004), the Wernicke area (p < 0.023) and a positive correlation was found in the dorsolateral prefrontal cortex (DLPFC) (p < 0.014). In line with the dysconnection findings in schizophrenia, our results provide preliminary evidence for a targeted alteration in the brain network hubs' organization in individuals with a genetic risk for schizophrenia. The study of specific disorganization in language, speech and thought regulation networks sharing similar network properties may help to understand their role in the hallucination mechanism.
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A multicomponent indicator displacement assay ( MIDA) based on an organometallic receptor and three dyes can be used for the identification and quantification of nucleotides in aqueous solution at neutral pH.
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We conducted an open, randomized, and prospective study to determine the effect of hypertonic saline on the secretion of antidiuretic hormone (ADH) and aldosterone in children with severe head injury (Glasgow coma scale <8). Thirty-one consecutive patients at a level III pediatric intensive care unit at a children's hospital received either lactated Ringer's solution (Ringer's group, n = 16) or hypertonic saline (Hypertonic Saline group, n = 15) over a 3-day period. Serum ADH levels were significantly larger in the Hypertonic Saline group as compared with the Ringer's group (P = 0.001; analysis of variance) and were correlated to sodium intake (Ringer's group: r = 0.39, R(2) = 0.15, P = 0.02; Hypertonic Saline group: r = 0.42, R(2) = 0.18, P = 0.02) and volume of fluids given IV (Ringer's group: r = 0.38, R(2) = 0.15, P = 0.02; Hypertonic Saline group: r = 0.32, R(2) = 0.1, P = not significant). Correlation of ADH to plasma osmolality was significant if plasma osmolality was >280 mOsm/kg (r = 0.5, R(2) = 0.25, P = 0.06), indicating an osmotic threshold for ADH release. Serum aldosterone levels were larger on the first day than during Days 2 and 3 in both groups and inversely correlated to serum sodium levels only in the Ringer's group (r = -0.55, R(2) = 0.3, P < 0.001). This group received a significantly larger fluid volume on Day 1 (P = 0.05, Mann-Whitney U-test) than did patients in the Hypertonic Saline group, indicating hypovolemia during the first day. Head-injured children have appropriate levels of ADH. They may be hypovolemic during the first day of treatment, especially if they receive lactated Ringer's solution. IMPLICATIONS: In head-injured patients, we recommend fluid restriction to avoid inappropriate secretion of antidiuretic hormone. In a prospective, randomized, and controlled study in 31 children, we were able to show that the antidiuretic hormone levels are appropriate in response to hypovolemia, sodium load, or both.
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The Brianconnais area is explained as a large scale exotic terrain separating from Europe during the opening of the Valais ocean. It's displacement history during the Alpine evolution allows to replace older concepts of multiple oceans separating narrow strips of continental crust.
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The use of quantum dots (QDs) in the area of fingermark detection is currently receiving a lot of attention in the forensic literature. Most of the research efforts have been devoted to cadmium telluride (CdTe) quantum dots often applied as powders to the surfaces of interests. Both the use of cadmium and the nano size of these particles raise important issues in terms of health and safety. This paper proposes to replace CdTe QDs by zinc sulphide QDs doped with copper (ZnS:Cu) to address these issues. Zinc sulphide-copper doped QDs were successfully synthesized, characterized in terms of size and optical properties and optimized to be applied for the detection of impressions left in blood, where CdTe QDs proved to be efficient. Effectiveness of detection was assessed in comparison with CdTe QDs and Acid Yellow 7 (AY7, an effective blood reagent), using two series of depletive blood fingermarks from four donors prepared on four non-porous substrates, i.e. glass, transparent polypropylene, black polyethylene and aluminium foil. The marks were cut in half and processed separately with both reagents, leading to two comparison series (ZnS:Cu vs. CdTe, and ZnS:Cu vs. AY7). ZnS:Cu proved to be better than AY7 and at least as efficient as CdTe on most substrates. Consequently, copper-doped ZnS QDs constitute a valid substitute for cadmium-based QDs to detect blood marks on non-porous substrates and offer a safer alternative for routine use.
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An image analysis method is presented which allows for the reconstruction of the three-dimensional path of filamentous objects from two of their projections. Starting with stereo pairs, this method is used to trace the trajectory of DNA molecules embedded in vitreous ice and leads to a faithful representation of their three-dimensional shape in solution. This computer-aided reconstruction is superior to the subjective three-dimensional impression generated by observation of stereo pairs of micrographs because it enables one to look at the reconstructed molecules from any chosen direction and distance and allows quantitative analysis such as determination of distances, curvature, persistence length, and writhe of DNA molecules in solution.
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Introduction: Le captopril, inhibiteur de l'enzyme de conversion de l'angiotensine, est largement utilisé dans le traitement de l'hypertension artérielle et de l'insuffisance cardiaque chez l'adulte et l'enfant . De par son instabilité en milieu aqueux (oxydation en captopril disulfure), il n'est actuellement commercialisé que sous forme de comprimés. La prescription fréquente de doses faibles et variables en pédiatrie justifiait le développement d'une forme orale liquide, tant sur le plan pratique et économique, que sur celui de la sécurité d'administration. Cependant toutes les formulations orales liquides publiées présentent une stabilité courte, ne dépassant guère 1 mois. Objectif: Développer une forme orale liquide de captopril d'une stabilité d'au moins 6 mois. Méthode: Sur la base des données de la littérature, élaboration de 8 formulations liquides différentes de captopril 1 mg/ml (concentration permettant le prélèvement d'un volume adéquat pour une administration en pédiatrie). Mise au point d'une « stability indicating method » par HPLC par des tests de dégradation accélérée à la chaleur (100°C), en milieu acide, basique, en présence d'un agent oxydant et de la lumière. Sélection de la formulation la plus stable durant le premier mois. Etude de stabilité sur 2 ans de 3 lots (3 échantillons/lot) dans leur conditionnement final à température ambiante (TA), au frigo et à 40° ± 2°C. Contrôle microbiologique au début et à la fin de l'étude selon la méthode de la Ph. Eur. (Ed. 3). Résultats: La formule retenue est une solution aqueuse de captopril 1 mg/ml additionnée d'EDTA 1 mg/ml comme stabilisateur et conditionnée dans des flacons VERAL en verre brun de 60 ml. Après dégradation dans les conditions définies ci-dessus, le pic du captopril est nettement séparé sur les chromatogrammes de ceux des produits de dégradation. Après 2 ans, la concentration mesurée est de 104.6% (±0.32%) au frigo, 103.6% (±0.86%) à TA et 96.5 % (±0.02%) à 40°C. Aucune croissance n'a été observée sur la durée de l'étude. Discussion et conclusion: La solution de captopril 1 mg/ml mise au point est simple à préparer. En partant du principe actif pur et en présence d'EDTA comme complexant, les traces de métaux éventuellement présents n'induisent pas l'oxydation du captopril et par conséquent le recours à d'autres stabilisateurs n'est pas nécessaire. La méthode HPLC développée est une « stability indicating method ». Les résultats de l'étude ont montré que cette solution a une durée de validité de 2 ans au frigo et à TA. Compte tenu du fait que la préparation ne contient pas d'agent antimicrobien, une conservation au frigo (2 - 8°C) est toutefois recommandée. La formule proposée présente un réel avantage en pédiatrie tant sur le plan de la sécurité d'administration que sur celui de l'économie.
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Softcatalà is a non-profit associationcreated more than 10 years ago to fightthe marginalisation of the Catalan languagein information and communicationtechnologies. It has led the localisationof many applications and thecreation of a website which allows itsusers to translate texts between Spanishand Catalan using an external closed-sourcetranslation engine. Recently,the closed-source translation back-endhas been replaced by a free/open-sourcesolution completely managed by Softcatalà: the Apertium machine translationplatform and the ScaleMT web serviceframework. Thanks to the opennessof the new solution, it is possibleto take advantage of the huge amount ofusers of the Softcatalà translation serviceto improve it, using a series ofmethods presented in this paper. In addition,a study of the translations requestedby the users has been carriedout, and it shows that the translationback-end change has not affected theusage patterns.
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The continuous wavelet transform is obtained as a maximumentropy solution of the corresponding inverse problem. It is well knownthat although a signal can be reconstructed from its wavelet transform,the expansion is not unique due to the redundancy of continuous wavelets.Hence, the inverse problem has no unique solution. If we want to recognizeone solution as "optimal", then an appropriate decision criterion hasto be adopted. We show here that the continuous wavelet transform is an"optimal" solution in a maximum entropy sense.
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Verkkoon kytkettävien laitteiden määrä on lisääntynyt viime vuosina, joka luo tarpeen reitittimille ja niiden ominaisuuksille. On muodostunut uusi tarve laitteille, jotka voivat yhdistää erilaisia verkkoja toisiinsa. Tällaisen reitittimen rakentamiseen tarvitaan vakaa alusta. Tällaisella alustalla luodaan mahdollisuus kuormittaa järjestelmää ilman suuria ongelmia. Tällainen alusta on Open Platform, joka on suunniteltu tällaisille toiminnoille ja yhdessä oikeanlaisen verkkoratkaisun kanssa sitä voidaan käyttää sille suunnitellussa ympäristössä. Tämän diplomityön tarkoituksena on arvioida neljää eri reititysohjelmistoa ja kahta eri IP pinoa. Työssä käytetyt testit on suunniteltu arviointia varten ja niiden tarkoituksena on tuoda esille ohjelmistoissa esiintyvät viat ja ongelmat. Kaikki testit ovat samoja kaikille ohjelmille ja tehdään samassa ympäristössä. Testit analysoidaan niiden ajon jälkeen ja niiden tulosten avulla tehdään päätös mitä näistä ohjelmistoista tullaan käyttämään seuraavan sukupolven avoimella alustalla, joka tulee toimimaan Nokian Intelligent Service Nodessa. Tämä verkon laite toimii yhdyskäytävänäerilaisten verkkojen välillä.